WorldWideScience

Sample records for deuterated isotopomers cd3i

  1. Direct Detection of Hardly Detectable Hidden Chirality of Hydrocarbons and Deuterated Isotopomers by a Helical Polyacetylene through Chiral Amplification and Memory.

    Science.gov (United States)

    Maeda, Katsuhiro; Hirose, Daisuke; Okoshi, Natsuki; Shimomura, Kouhei; Wada, Yuya; Ikai, Tomoyuki; Kanoh, Shigeyoshi; Yashima, Eiji

    2018-03-07

    We report the first direct chirality sensing of a series of chiral hydrocarbons and isotopically chiral compounds (deuterated isotopomers), which are almost impossible to detect by conventional optical spectroscopic methods, by a stereoregular polyacetylene bearing 2,2'-biphenol-derived pendants. The polyacetylene showed a circular dichroism due to a preferred-handed helix formation in response to the hardly detectable hidden chirality of saturated tertiary or chiroptical quaternary hydrocarbons, and deuterated isotopomers. In sharp contrast to the previously reported sensory systems, the chirality detection by the polyacetylene relies on an excess one-handed helix formation induced by the chiral hydrocarbons and deuterated isotopomers via significant amplification of the chirality followed by its static memory, through which chiral information on the minute and hidden chirality can be stored as an excess of a single-handed helix memory for a long time.

  2. Full-Dimensional Quantum Calculations of Vibrational Levels of NH4(+) and Isotopomers on An Accurate Ab Initio Potential Energy Surface.

    Science.gov (United States)

    Yu, Hua-Gen; Han, Huixian; Guo, Hua

    2016-04-14

    Vibrational energy levels of the ammonium cation (NH4(+)) and its deuterated isotopomers are calculated using a numerically exact kinetic energy operator on a recently developed nine-dimensional permutation invariant semiglobal potential energy surface fitted to a large number of high-level ab initio points. Like CH4, the vibrational levels of NH4(+) and ND4(+) exhibit a polyad structure, characterized by a collective quantum number P = 2(v1 + v3) + v2 + v4. The low-lying vibrational levels of all isotopomers are assigned and the agreement with available experimental data is better than 1 cm(-1).

  3. Deuteration of lidocaine

    International Nuclear Information System (INIS)

    Haedener, A.

    1988-01-01

    Stepwise deuteration of the acidic methylene group of lidocaine on a large scale using a moderate excess of 2 H 2 O in triethylamine/pyridine at 200 0 is described. The efficient and economical preparation of bideuterated lidocaine facilitates the use of this compound as an excellent internal standard in lidocaine determination or as a tracer in lidocaine pharmacokinetics. (author)

  4. Deuteration of lidocaine

    Energy Technology Data Exchange (ETDEWEB)

    Haedener, A.

    1988-01-01

    Stepwise deuteration of the acidic methylene group of lidocaine on a large scale using a moderate excess of /sup 2/H/sub 2/O in triethylaminepyridine at 200/sup 0/ is described. The efficient and economical preparation of bideuterated lidocaine facilitates the use of this compound as an excellent internal standard in lidocaine determination or as a tracer in lidocaine pharmacokinetics.

  5. Ab initio study of styrene isotopomers

    International Nuclear Information System (INIS)

    Zhang Jicheng; Tang Yongjian; Wu Weidong; Wang Hongyan; Zhu Zhenghe

    2002-01-01

    Using Gaussian98W program, the equilibrium geometry molecule structure of styrene has been optimized with HF/6-31G, MP2/6-31G and BLYP/6-31G methods. At same time, using BLYP/6-31G method, the harmonic frequency of styrene and its isotopomers, the bond energy of C-D bond (with ZPE correction), the intensity of IR spectrum are studied, and the modes of harmonic vibrational frequencies are simply discussed. At the same time, the effect of temperature and pressure on the thermodynamics parameter-entropy are studied. The results show that the calculated results are in good agreement with the experimental results

  6. Synthesis of deuterated 1-phenylpropenols

    International Nuclear Information System (INIS)

    Denhez, J.P.; Girault, G.; Dizabo, P.

    1981-01-01

    The synthesis of deuterated 1-phenylpropenols is reported. The methods involve either Grignard reactions or selective reduction of α, β unsaturated ketones. These ketones are obtained by degradation of ammonium salts of the Mannich bases. (author)

  7. Deuteration kinetics of the graphene

    Energy Technology Data Exchange (ETDEWEB)

    Nefedov, Alexei; Woell, Christof [KIT, Leopoldshafen (Germany); Paris, Alessio; Calliari, Lucia [FBK-CMM, Trento (Italy); Verbitskiy, Nikolay [MSU, Moscow (Russian Federation); University of Vienna, Vienna (Austria); Wang, Ying; Irle, Stephan [Nagoya University, Nagoya (Japan); Fedorov, Alexander [IFW Dresden, Dresden (Germany); St. Petersburg University, St. Petersburg (Russian Federation); Haberer, Danny; Knupfer, Martin; Buechner, Bernd [IFW Dresden, Dresden (Germany); Oetzelt, Martin [BESSY II, Berlin (Germany); Petaccia, Luca [Elettra, Trieste (Italy); Usachov, Dmitry [St. Petersburg University, St. Petersburg (Russian Federation); Vyalikh, Denis [St. Petersburg University, St. Petersburg (Russian Federation); TU Dresden, Dresden (Germany); Sagdev, Hermann [MPI fuer Polymerforschung, Mainz (Germany); Yashina, Lada [MSU, Moscow (Russian Federation); Grueneis, Alexander [IFW Dresden, Dresden (Germany); University of Vienna, Vienna (Austria)

    2013-07-01

    The kinetics of the hydrogenation/deuteration reaction of graphene was studied by time-dependent x-ray photoemission spectroscopy (XPS). The graphene layer was then exposed to hydrogen or deuterium atomic gas beams, obtained by thermal cracking in a tungsten capillary at T=3000 K. After each step XPS of the C1s line was performed in order to measure H/C and D/C ratios. We have observed a strong kinetic isotope effect for the hydrogenation/deuteration reaction leading to substantially faster adsorption and higher maximum D/C ratios as compared to H/C (D/C 35% vs. H/C 25%).

  8. Spectroscopic study on deuterated benzenes. I. Microwave spectra and molecular structure in the ground state

    Energy Technology Data Exchange (ETDEWEB)

    Kunishige, Sachi; Katori, Toshiharu; Baba, Masaaki, E-mail: baba@kuchem.kyoto-u.ac.jp [Division of Chemistry, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan); Nakajima, Masakazu; Endo, Yasuki [Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

    2015-12-28

    We observed microwave absorption spectra of some deuterated benzenes and accurately determined the rotational constants of all H/D isotopomers in the ground vibrational state. Using synthetic analysis assuming that all bond angles are 120°, the mean bond lengths were obtained to be r{sub 0}(C–C) = 1.3971 Å and r{sub 0}(C–H) = r{sub 0}(C–D) = 1.0805 Å. It has been concluded that the effect of deuterium substitution on the molecular structure is negligibly small and that the mean bond lengths of C–H and C–D are identical unlike small aliphatic hydrocarbons, in which r{sub 0}(C–D) is about 5 mÅ shorter than r{sub 0}(C–H). It is considered that anharmonicity is very small in the C–H stretching vibration of aromatic hydrocarbons.

  9. Heterologous expression of a deuterated membrane-integrated receptor and partial deuteration in methylotrophic yeasts

    International Nuclear Information System (INIS)

    Massou, S.; Puech, V.; Talmont, F.; Demange, P.; Lindley, N.D.; Tropis, M.; Milon, A.

    1999-01-01

    Methylotrophic yeast has previously been shown to be an excellent system for the cost-effective production of perdeuterated biomass and for the heterologous expression of membrane receptors. A protocol for the expression of 85% deuterated, functional human μ-opiate receptor was established. For partially deuterated biomass, deuteration level and distribution were determined for fatty acids, amino acids and carbohydrates. It was shown that prior to biosynthesis of lipids and amino acids (and of carbohydrates, to a lower extent), exchange occurs between water and methanol hydrogen atoms, so that 80%-90% randomly deuterated biomass and over-expressed proteins may be obtained using only deuterated water

  10. Continuous measurements of nitrous oxide isotopomers during incubation experiments

    Science.gov (United States)

    Winther, Malte; Balslev-Harder, David; Christensen, Søren; Priemé, Anders; Elberling, Bo; Crosson, Eric; Blunier, Thomas

    2018-02-01

    Nitrous oxide (N2O) is an important and strong greenhouse gas in the atmosphere. It is produced by microbes during nitrification and denitrification in terrestrial and aquatic ecosystems. The main sinks for N2O are turnover by denitrification and photolysis and photo-oxidation in the stratosphere. In the linear N = N = O molecule 15N substitution is possible in two distinct positions: central and terminal. The respective molecules, 14N15N16O and 15N14N16O, are called isotopomers. It has been demonstrated that N2O produced by nitrifying or denitrifying microbes exhibits a different relative abundance of the isotopomers. Therefore, measurements of the site preference (difference in the abundance of the two isotopomers) in N2O can be used to determine the source of N2O, i.e., nitrification or denitrification. Recent instrument development allows for continuous position-dependent δ15N measurements at N2O concentrations relevant for studies of atmospheric chemistry. We present results from continuous incubation experiments with denitrifying bacteria, Pseudomonas fluorescens (producing and reducing N2O) and Pseudomonas chlororaphis (only producing N2O). The continuous measurements of N2O isotopomers reveals the transient isotope exchange among KNO3, N2O, and N2. We find bulk isotopic fractionation of -5.01 ‰ ± 1.20 for P. chlororaphis, in line with previous results for production from denitrification. For P. fluorescens, the bulk isotopic fractionation during production of N2O is -52.21 ‰ ± 9.28 and 8.77 ‰ ± 4.49 during N2O reduction.The site preference (SP) isotopic fractionation for P. chlororaphis is -3.42 ‰ ± 1.69. For P. fluorescens, the calculations result in SP isotopic fractionation values of 5.73 ‰ ± 5.26 during production of N2O and 2.41 ‰ ± 3.04 during reduction of N2O. In summary, we implemented continuous measurements of N2O isotopomers during incubation of denitrifying bacteria and believe that similar experiments will lead to a better

  11. Synthesis and characterization of deuterated polyethylene

    International Nuclear Information System (INIS)

    Jia Xianbin; Luo Xuan; Chang Guanjun; Du Kai; Zhang Lin; Xie Zhengwei; Li Xinjuan; Lu Zaijun

    2009-01-01

    Due to its remarkable isotope effects, excellent kinetic stability towards C-D bond break, high degree of deuteration, and being non-radioactive, deuterated polyethylene (d-PE) is widely used in many fields, such as in inertially confined fusion (ICF) as target material, in production of low loss plastic optical fibers, and in study of the compatibility of different polymers. For the necessary of ICF, the d-PE was synthesized by the anionic polymerization and palladium-catalyzed hydrogenation. Furthermore, by the method of FTIR, 1H NMR and GPC, the deuterated ratio and structure of d-PE have been characterized. The results show that the d-PE has the high deuterated ratio and molecular weight, narrow molecular-weight distribution, the polymer material fits the basic necessary of ICF. (authors)

  12. Applications of deuteration for neutron scattering, at the Australian National Deuteration Facility

    International Nuclear Information System (INIS)

    Holden, Peter

    2009-01-01

    ANSTO and Australia National Collaborative Research Infrastructure Strategy have funded a 4 year program to establish the National Deuteration Facility (NDF) which offers both in vivo deuteration of biomolecules and chemical deuteration of synthesised organic molecules to the structural biology and soft matter communities in Australia and internationally. The NDF has bio deuterated a range of native and novel polyhydroxy alkanoate (PHA) bio polyesters and is using deuterated polymers to probe interfacial phenomena in PHA/ ethyl cellulose blends and the chain behaviour of PHAs in solution using SANS. The NDF has also undertaken partial deuteration of proteins to investigate the disposition of protein subunits in complexes and protein interactions using SANS as well as per deuteration of proteins for neutron crystallographic studies.αB-crystalline is a molecular chaperone of the small heat shock protein family which prevents the formation of amyloid fibrils in various proteins including α-synuclein which is implicated in Parkinson disease. Deuteration is being used to facilitate investigation of the multimeric distribution of the A and B subunits in the 32 mer chaperone, and the mode of interaction with α-synuclein in prevention of fibril formation. Similarly, deuteration of selected subunits of magnesium chelatase (the enzyme responsible for insertion of Mg 2+ into protoporphyrin) and SANS will be used to support or exclude competing models of their organisation. Two laboratories for chemical synthesis and characterisation of completely, partially, or selectively deuterated compounds were established during 2008. Methodological trials have commenced and success demonstrated for deuterated fatty acids, alcohols, surfactants, glycols and amino acids. Such deuterated molecules will be useful in investigation of co-polymer structure, polymer behaviour in solution, micelle behaviour and bio membrane phenomena using SANS and neutron reflectometry. For example, NDF

  13. Continuous measurements of nitrous oxide isotopomers during incubation experiments

    DEFF Research Database (Denmark)

    Winther, Malte Nordmann; Balslev-Harder, David; Christensen, Søren

    2016-01-01

    relevant for studies of atmospheric chemistry. We present results from continuous incubation experiments with denitrifying bacteria, Pseudomonas fluorescens (producing and reducing N2O) and P. chlororaphis (only producing N2O). The continuous position dependent measurements reveal the transient pattern....... fluorescens, the calculations results in SP values of −5.7 ‰ ± 5.6 during production of N2O and 2.3 ‰ ± 3.2 during reduction of N2O. In summary, we implemented continuous measurements of N2O isotopomers during incubation of denitrifying bacteria and believe that similar experiments will lead to a better...... understanding of denitrifying bacteria and N2O turnover in soils and sediments and ultimately hands-on knowledge on the biotic mechanisms behind greenhouse gas exchange of the Globe....

  14. Deuteration of benzen derivatives and condensed aromatics

    International Nuclear Information System (INIS)

    Ichikawa, Masaru.

    1970-01-01

    A process for the deuteration of aromatic compounds (benzene derivatives having one or more cyano, halogeno, nitro or other electron attractive groups, and condensed ring aromatics) is provided. The process comprises reducing said aromatic compound with an alkali metal (preferably K, Rb or Cs) in a solvent (dimethoxyethane, tetrahydrofuran, etc.) to provide an electron-acceptor-donor complex, which is followed by introducing gaseous deuterium into the solution. The deuteration takes place selectively at the position of highest electron density in accordance with nature of the substituent, regardless of steric hindrance. The process is applicable to a wide variety of aromatics to give deuterated compounds in high yields. In one example, 5x10 -3 mole of anthracene (An) was reacted with 2g of metallic potassium in 80cc of dimethoxyethane in a N 2 atmosphere. Into the resulting solution of An=2K + was introduced D 2 gas (30 cmHg) at 25 0 C. After decomposition with air and washing with alcohol, the precipitate was recrystallized from benzene. Yield of recovered AN: more than 90%. Yield of deuteration: 100%. Position of deuteration: 9 and 10 (revealed by NMR and mass spectroscopy). (Kaichi, S.)

  15. Synthesis and properties of deuterated polystyrene

    International Nuclear Information System (INIS)

    Liu Chang; Jin Rong; Xu Yewei; Zhang Lin; Yan Hongwei; Du Kai; Wei Chengfu

    2012-01-01

    Deuterated poly(vinylcyclohexane) (D-PVCH, C 8 H 8 D 6 ) was successfully prepared via deuterated catalytic technology of polystyrene (PS). The structure of D-PVCH was characterized by FT-IR and 1 HNMR spectroscopy, and the results show good agreement with the proposed structure and the deuterated ratio is 41.5%. DSC and TG analyses of the D-PVCH show that D-PVCH possesses good thermal stability (glass transition temperature of 125 ℃, 5% weight loss temperature of 403 ℃). Additionally, D-PVCH dissolves in common solvents such as petroleum ether, cyclohexane and toluene at room temperature. Compared with PS, D-PVCH possesses better thermal stability and improved solubility. (authors)

  16. Deuterated drugs; updates and obviousness analysis.

    Science.gov (United States)

    Timmins, Graham S

    2017-12-01

    The pharmacokinetics and/or toxicity of many known drugs can be modified by selective deuteration, an area of significant commercial interest and scientific and regulatory progress. Areas covered: This review firstly discusses recent developments in deuterated drugs including the FDA approval of deutetrabenazine. Secondly, it discusses 35 U.S.C. §103 'obviousness' as it relates to recent patent prosecution, and also to Inter Partes Review (IPR). IPR is a new post-award review of patentability under §102 or §103, two IPR petitions upon deuterated drugs have been instituted and included §103 arguments. Finally, an extended analysis of §103 obviousness based upon the practices of major pharmaceutical companies is provided, that supports rather late priority dates, while §102 is also discussed. Expert opinion: The total value of transactions involving deuterated drugs is close to $5 billion. While the importance of §103 'obviousness' rejections remains in patent applications under current prosecution, IPR of issued patents is developing and will affect likely affect §103 interpretations in this area. However, patents are still issuing with later priority dates, and further litigation will likely occur.

  17. Methods for preparation of deuterated amino acids

    International Nuclear Information System (INIS)

    Pshenichnikova, A.B.; Karnaukhova, E.N.; Zvonkova, E.N.

    1995-01-01

    The current state and prospects for the use of amino acids labeled with stable isotopes are considered. Methods for the preparation of deuterated amino acids, including synthetic, chemicoenzymatic, and biosynthetic ones, and deuterium exchange reactions are summarized. Problems in the preparation of optically pure amino acids are discussed. 120 refs., 15 figs

  18. Determination of isotopomers in pools of molecules with polyisotopic elements

    International Nuclear Information System (INIS)

    Zyakun, A.M.; Brenninkmeijer, C.A.M.

    2002-01-01

    Polyisotopic element atoms that are present in a molecule form a pool of isotopomer molecules. Mono- and polyisotopomers are distinguished depending on the quantity of atoms of polyisotopic elements. Methodical approaches have been considered for the quantitative determination of the isotope composition of an element included in mono- and polyisotopic molecules. A possibility of the equally probable (homogeneous) and non-equally probable (non-homogeneous) distribution of isotopes of a polyisotopic element, the atoms of which have different positions in the molecule of polyisotopomer, has been shown. Factors disturbing the homogeneous distribution of isotopes of the element in the polyisotopomer pool have been revealed. When a polyisotopomer is involved in a mass-dependent process or reaction, the homogeneity of isotope distribution of the element is disturbed both in the residual and newly formed pools of polyisotopomer. By the example of CO 2 (polyisotopomer by oxygen) it has been shown that one can judge of the history of the analyzed pool formation by distribution of oxygen isotopes within this pool. The isotope content in the oxygen sites of polyisotopomer is a diagnostic feature of CO 2 involvement in the efflux from a reservoir or influx to the analyzed reservoir from an external source. (author)

  19. Isotopomer fractionation during photolysis of nitrous oxide by ultraviolet of 206 to 210 nm

    International Nuclear Information System (INIS)

    Toyoda, S.; Yoshida, N.; Suzuki, T.; Tsuji, K.; Shibuya, K.

    2002-01-01

    Nitrous oxide (N 2 O) is an important trace gas in the stratospheric chemistry as well as in the tropospheric radiative balance. Although there have been observations on the distribution of N 2 O in the atmosphere and its flux from individual sources, the global N 2 O budget is not fully understood. The isotopic information of N 2 O has been useful for constraining the N 2 O cycle since each source and sink has its own isotopic signature and isotope fractionation that is unique to the process. We have recently developed a method to determine isotopomers of N 2 O and showed that intramolecular distribution of 15 N is a parameter that has more fundamental and sensitive information than bulk 15 N abundance for constraining the atmospheric N 2 O budget. Here, we report the fractionation of isotopomers during ultraviolet photolysis of N 2 O in a 206 to 210 nm region. The fractionation factors are different among isotopomers and the site preference between two nitrogen isotopomers becomes larger along with the photolysis. The isotopomer fractionation factors of this representative wavelength are close to the apparent fractionation factors observed in the stratosphere indicating ultraviolet photolysis in the stratosphere is the dominant sink of N 2 O. Sources of atmospheric N 2 O including terrestrial and oceanic biological processes, agricultural activities, industrial formation and fossil fuel combustion are expected to be characterized to better constrain the global budget of N 2 O. (author)

  20. Boronization on NSTX using Deuterated Trimethylboron

    International Nuclear Information System (INIS)

    Blanchard, W.R.; Gernhardt, R.C.; Kugel, H.W.; LaMarche, P.H.

    2002-01-01

    Boronization on the National Spherical Torus Experiment (NSTX) has proved to be quite beneficial with increases in confinement and density, and decreases in impurities observed in the plasma. The boron has been applied to the interior surfaces of NSTX, about every 2 to 3 weeks of plasma operation, by producing a glow discharge in the vacuum vessel using deuterated trimethylboron (TMB) in a 10% mixture with helium. Special NSTX requirements restricted the selection of the candidate boronization method to the use of deuterated boron compounds. Deuterated TMB met these requirements, but is a hazardous gas and special care in the execution of the boronization process is required. This paper describes the existing GDC, Gas Injection, and Torus Vacuum Pumping System hardware used for this process, the glow discharge process, and the automated control system that allows for remote operation to maximize both the safety and efficacy of applying the boron coating. The administrative requirements and the detailed procedure for the setup, operation and shutdown of the process are also described

  1. Modeling Non-Steady Isotopologue and Isotopomer Speciation and Fractionation during Denitrification in Soils

    Science.gov (United States)

    Maggi, F.; Riley, W. J.

    2009-12-01

    The composition and location of 15N atoms on N2O isotopomers and isotopologues during isotope speciation has been used to characterize soil biological N cycling and N2O surface emissions. Although there exist few experimental observations, no attempt has been made to model N2O isotopomer speciation. The mathematical treatment of biological kinetic reactions in isotopic applications normally makes use of first-order and quasi steady-state complexation assumptions without taking into account changes in enzyme concentration, reaction stoichiometry, and isotopologue and isotopomer speciation. When multiatomic isotopically-labeled reactants are used in a multi-molecurar reaction, these assumptions may fail since they always lead to a constant fractionation factor and cannot describe speciation of isotopologues and isotopomers. We have developed a mathematical framework that is capable of describing isotopologue and isotopmer speciation and fractionation under the assumption of non-steady complexation during biological kinetic reactions that overcome the limitations mentioned above. This framework was applied to a case study of non-steady (variable and inverse) isotopic effects observed during N2O production and consumption in soils. Our mathematical treatment has led to generalized kinetic equations which replicate experimental observations with high accuracy and help interpret non-steady isotopic effects and isotopologue and isotopomer speciation. The kinetic equations introduced and applied here have general validity in describing isotopic effects in any biochemical reactions by considering: changing enzyme concentrations, mass and isotope conservation, and reaction stoichiometry. The equations also describe speciation of any isotopologue and isotopomer product from any isotopologue and isotopmer reactant.

  2. High bandwidth second-harmonic generation in partially deuterated KDP

    International Nuclear Information System (INIS)

    Webb, M.S.; Eimerl, D.; Velsko, S.P.

    1992-01-01

    We have experimentally determined the spectrally noncritical phasematching behavior of Type I frequency doubling in KDP and its dependence on deuteration level in partially deuterated KDP. The first order wavelength sensitivity parameter∂Δk/∂γ for Type I doubling of 1.053 μm light vanishes for a KD*P crystal with a deuteration level between 10 and 14%. Very high bandwidth frequency doubling of Nd:glass lasers is possible with such a crystal

  3. Laboratory Measurements for H3+ Deuteration Reactions

    Science.gov (United States)

    Bowen, Kyle; Hillenbrand, Pierre-Michel; Urbain, Xavier; Savin, Daniel Wolf

    2018-06-01

    Deuterated molecules are important chemical tracers of protostellar cores. At the ~106 cm-3 particle densities and ~20 K temperatures typical for protostellar cores, most molecules freeze onto dust grains. A notable exception is H3+ and its isotopologues. These become important carriers of positive charge in the gas, can couple to any ambient magnetic field, and can thereby alter the cloud dynamics. Knowing the total abundance of H3+ and its isotopologues is important for studying the evolution of protostellar cores. However, H3+ and D3+ have no dipole moment. They lack a pure rotational spectrum and are not observable at protostellar core temperatures. Fortunately H2D+ and D2H+ have dipole moments and a pure rotational spectrum that can be excited in protostellar cores. Observations of these two molecules, combined with astrochemical models, provide information about the total abundance of H3+ and all its isotopologues. The inferred abundances, though, rely on accurate astrochemical data for the deuteration of H3+ and its isotopologues.Here we present laboratory measurements of the rate coefficients for three important deuterating reactions, namely D + H3+/H2D+/D2H+ → H + H2D+/ D2H+/D3+. Astrochemical models currently rely on rate coefficients from classical (Langevin) or semi-classical methods for these reactions, as fully quantum-mechanical calculations are beyond current computational capabilities. Laboratory studies are the most tractable means of providing the needed data. For our studies we used our novel dual-source, merged fast-beams apparatus, which enables us to study reactions of neutral atoms and molecular ions. Co-propagating beams allow us to measure experimental rate coefficients as a function of collision energy. We extract cross section data from these results, which we then convolve with a Maxwell-Boltzmann distribution to generate thermal rate coefficients. Here we present our results for these three reactions and discuss some implications.

  4. Mild Conditions for Deuteration of Primary and Secondary Arylamines for the Synthesis of Deuterated Optoelectronic Organic Molecules

    Directory of Open Access Journals (Sweden)

    Anwen M. Krause-Heuer

    2014-11-01

    Full Text Available Deuterated arylamines demonstrate great potential for use in optoelectronic devices, but their widespread utility requires a method for large-scale synthesis. The incorporation of these deuterated materials into optoelectronic devices also provides the opportunity for studies of the functioning device using neutron reflectometry based on the difference in the scattering length density between protonated and deuterated compounds. Here we report mild deuteration conditions utilising standard laboratory glassware for the deuteration of: diphenylamine, N-phenylnaphthylamine, N-phenyl-o-phenylenediamine and 1-naphthylamine (via H/D exchange in D2O at 80 °C, catalysed by Pt/C and Pd/C. These conditions were not successful in the deuteration of triphenylamine or N,N-dimethylaniline, suggesting that these mild conditions are not suitable for the deuteration of tertiary arylamines, but are likely to be applicable for the deuteration of other primary and secondary arylamines. The deuterated arylamines can then be used for synthesis of larger organic molecules or polymers with optoelectronic applications.

  5. Deuteration of metals through electric discharges

    International Nuclear Information System (INIS)

    Balderas G, L.M.

    1995-01-01

    In this work deuteration of titanium and a stainless steel through electrical discharges in a vacuum chamber was performed at different thermodynamic conditions. The samples were plates of 0.03 x 4.5 x 54 cm. The titanium sample was first cleaning with chloroform. The oxide layer was removed by cleaning the sample with a 1:1:1 mixture of water, nitric acid and sulphuric acid. Later was rinsed in water and dried with acetone. Finally, was treated with HCl to form an hydride layer on the surface. The stainless steel sample was only cleaned with soap and cleaning with acetone. The samples were cleaning at low pressure for several days with high temperature short cycles. The deuterium was loaded to the chamber at room temperature having absorption on the titanium samples at 10 3 at 10 1 mbar. Afterwards that the samples were heated up at 330 C and was observed the deuterium absorption in the same pressure range. Forced deuteration through electrical discharges between the sample and the chamber was tried obtaining absorption in the range of 10 3 at 10 2 mbar, however the deuterium absorption only was observed in specific cases. In order to detect neutron emission or released particles in this experiment were used alanine detectors and series of plastic CR-39 and borate films. No neutron were detected in the passive systems used in the experiments. (Author)

  6. State of mixing of deuterated and non-deuterated block polymer chains

    International Nuclear Information System (INIS)

    Hasegawa, Hirokazu; Hashimoto, Takeji

    1984-01-01

    Prior to the small-angle neutron scattering study on the conformation of block polymer chains in the domain space, the state of mixing of two block polymers, an ordinary polystyrene-polyisoprene diblock polymer and a poly(deuterated styrene)-polyisoprene diblock polymer with a different molecular weight and composition, was investigated by a small-angle X-ray scattering (SAXS) technique. Only one kind of domain structure was observed for each blend, and the domain spacings obtained by SAXS were proportional to the two-thirds power of the number-average molecular weight of the blends (reduced to non-deuterated block polymer). The volume fractions of polystyrene domain in the blends evaluated by computer simulation of SAXS profiles well agreed with the values estimated from blend composition. All these facts suggest the molecular mixing of the two block polymers in the domain space. (author)

  7. Neutron Compton scattering from selectively deuterated acetanilide

    Science.gov (United States)

    Wanderlingh, U. N.; Fielding, A. L.; Middendorf, H. D.

    With the aim of developing the application of neutron Compton scattering (NCS) to molecular systems of biophysical interest, we are using the Compton spectrometer EVS at ISIS to characterize the momentum distribution of protons in peptide groups. In this contribution we present NCS measurements of the recoil peak (Compton profile) due to the amide proton in otherwise fully deuterated acetanilide (ACN), a widely studied model system for H-bonding and energy transfer in biomolecules. We obtain values for the average width of the potential well of the amide proton and its mean kinetic energy. Deviations from the Gaussian form of the Compton profile, analyzed on the basis of an expansion due to Sears, provide data relating to the Laplacian of the proton potential.

  8. Isotopomer distributions in amino acids from a highly expressed protein as a proxy for those from total protein

    Energy Technology Data Exchange (ETDEWEB)

    Shaikh, Afshan; Shaikh, Afshan S.; Tang, Yinjie; Mukhopadhyay, Aindrila; Keasling, Jay D.

    2008-06-27

    {sup 13}C-based metabolic flux analysis provides valuable information about bacterial physiology. Though many biological processes rely on the synergistic functions of microbial communities, study of individual organisms in a mixed culture using existing flux analysis methods is difficult. Isotopomer-based flux analysis typically relies on hydrolyzed amino acids from a homogeneous biomass. Thus metabolic flux analysis of a given organism in a mixed culture requires its separation from the mixed culture. Swift and efficient cell separation is difficult and a major hurdle for isotopomer-based flux analysis of mixed cultures. Here we demonstrate the use of a single highly-expressed protein to analyze the isotopomer distribution of amino acids from one organism. Using the model organism E. coli expressing a plasmid-borne, his-tagged Green Fluorescent Protein (GFP), we show that induction of GFP does not affect E. coli growth kinetics or the isotopomer distribution in nine key metabolites. Further, the isotopomer labeling patterns of amino acids derived from purified GFP and total cell protein are indistinguishable, indicating that amino acids from a purified protein can be used to infer metabolic fluxes of targeted organisms in a mixed culture. This study provides the foundation to extend isotopomer-based flux analysis to study metabolism of individual strains in microbial communities.

  9. Study of deutero-isotopomer-induced inhibition of caffeine and phenobarbitone binding to human serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Cherrah, Y.; Falconnet, J.B.; Desage, M.; Brazier, J.L.; Zini, R.; Tillement, J.P.

    1988-01-01

    The present study of inhibition provides confirmation to previously observed deuterium isotope effects on in vitro caffeine and phenobarbitone binding to human serum albumin (HSA). Addition of either 3,7(C(/sup 2/H)/sub 3/)/sub 2/ or 1,3,7(C(/sup 2/H)/sub 3/)/sub 3/ caffeine induces a 50% loss in both the extent of binding and binding parameters of the unlabelled analog. As concerns caffeine displacement from its HSA sites, it is shown that phenobarbitone and its 5-pentadeuterophenyl analog are equally potent inhibitors of caffeine binding, though individual HSA binding profiles differ. As for HSA binding interactions between phenobarbitone isotopomers, a 50% decrease in unlabelled phenobarbitone extent of binding is observed in the presence of its 5-pentadeuterophenyl analog. Results favor the hypothesis of differing binding sites for each isotopomer.

  10. 'Isotopo' a database application for facile analysis and management of mass isotopomer data.

    Science.gov (United States)

    Ahmed, Zeeshan; Zeeshan, Saman; Huber, Claudia; Hensel, Michael; Schomburg, Dietmar; Münch, Richard; Eylert, Eva; Eisenreich, Wolfgang; Dandekar, Thomas

    2014-01-01

    The composition of stable-isotope labelled isotopologues/isotopomers in metabolic products can be measured by mass spectrometry and supports the analysis of pathways and fluxes. As a prerequisite, the original mass spectra have to be processed, managed and stored to rapidly calculate, analyse and compare isotopomer enrichments to study, for instance, bacterial metabolism in infection. For such applications, we provide here the database application 'Isotopo'. This software package includes (i) a database to store and process isotopomer data, (ii) a parser to upload and translate different data formats for such data and (iii) an improved application to process and convert signal intensities from mass spectra of (13)C-labelled metabolites such as tertbutyldimethylsilyl-derivatives of amino acids. Relative mass intensities and isotopomer distributions are calculated applying a partial least square method with iterative refinement for high precision data. The data output includes formats such as graphs for overall enrichments in amino acids. The package is user-friendly for easy and robust data management of multiple experiments. The 'Isotopo' software is available at the following web link (section Download): http://spp1316.uni-wuerzburg.de/bioinformatics/isotopo/. The package contains three additional files: software executable setup (installer), one data set file (discussed in this article) and one excel file (which can be used to convert data from excel to '.iso' format). The 'Isotopo' software is compatible only with the Microsoft Windows operating system. http://spp1316.uni-wuerzburg.de/bioinformatics/isotopo/. © The Author(s) 2014. Published by Oxford University Press.

  11. Fully deuterated microorganisms: Tools in magnetic resonance and neutron scattering

    International Nuclear Information System (INIS)

    Crespi, H.L.

    1988-01-01

    Current work at Argonne emphasizes the use of fully deuterated algae and cyanobacteria as tools in the study of photosynthesis and as a source of complex substrates for the culture of engineered overproducing bacteria. 17 refs., 1 fig., 1 tab

  12. Deuteration effect on the rotary power of hydrogen bonded compounds

    International Nuclear Information System (INIS)

    Kolbe, A.; Kolbe, A.; Martin-Luther-Universitaet Halle-Wittenberg, Halle

    1982-01-01

    The variation of the rotatory power caused by deuteration in menthol, isopulegol, α-terpineol-(4), elemol, and diphenylacetyl-L-leucin has been investigated. The results and a brief discussion are given

  13. Deuteration effect on the rotary power of hydrogen bonded compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kolbe, A.; Kolbe, A. (Akademie der Wissenschaften der DDR, Halle/Saale. Inst. fuer Biochemie der Pflanzen; Martin-Luther-Universitaet Halle-Wittenberg, Halle (German Democratic Republic). Sektion Chemie)

    1982-01-01

    The variation of the rotatory power caused by deuteration in menthol, isopulegol, ..cap alpha..-terpineol-(4), elemol, and diphenylacetyl-L-leucin has been investigated. The results and a brief discussion are given.

  14. Pulse height model for deuterated scintillation detectors

    International Nuclear Information System (INIS)

    Wang, Haitang; Enqvist, Andreas

    2015-01-01

    An analytical model of light pulse height distribution for finite deuterated scintillation detectors is created using the impulse approximation. Particularly, the energy distribution of a scattered neutron is calculated based on an existing collision probability scheme for general cylindrical shaped detectors considering double differential cross-sections. The light pulse height distribution is analytically and numerically calculated by convoluting collision sequences with the light output function for an EJ-315 detector from our measurements completed at Ohio University. The model provides a good description of collision histories capturing transferred neutron energy in deuterium-based scintillation materials. The resulting light pulse height distribution details pulse compositions and their corresponding contributions. It shows that probabilities of neutron collision with carbon and deuterium nuclei are comparable, however the light pulse amplitude due to collisions with carbon nuclei is small and mainly located at the lower region of the light pulse distribution axis. The model can explore those neutron interaction events that generate pulses near or below a threshold that would be imposed in measurements. A comparison is made between the light pulse height distributions given by the analytical model and measurements. It reveals a significant probability of a neutron generating a small light pulse due to collisions with carbon nuclei when compared to larger light pulse generated by collisions involving deuterium nuclei. This model is beneficial to understand responses of scintillation materials and pulse compositions, as well as nuclei information extraction from recorded pulses.

  15. Production of deuterated switchgrass by hydroponic cultivation.

    Science.gov (United States)

    Evans, Barbara R; Bali, Garima; Foston, Marcus; Ragauskas, Arthur J; O'Neill, Hugh M; Shah, Riddhi; McGaughey, Joseph; Reeves, David; Rempe, Caroline S; Davison, Brian H

    2015-07-01

    The bioenergy crop switchgrass was grown hydroponically from tiller cuttings in 50 % D 2 O to obtain biomass with 34 % deuterium substitution and physicochemical properties similar to those of H 2 O-grown switchgrass controls. Deuterium enrichment of biological materials can potentially enable expanded experimental use of small angle neutron scattering (SANS) to investigate molecular structural transitions of complex systems such as plant cell walls. Two key advances have been made that facilitate cultivation of switchgrass, an important forage and biofuel crop, for controlled isotopic enrichment: (1) perfusion system with individual chambers and (2) hydroponic growth from tiller cuttings. Plants were grown and maintained for several months with periodic harvest. Photosynthetic activity was monitored by measurement of CO2 in outflow from the growth chambers. Plant morphology and composition appeared normal compared to matched controls grown with H2O. Using this improved method, gram quantities of switchgrass leaves and stems were produced by continuous hydroponic cultivation using growth medium consisting of basal mineral salts in 50 % D2O. Deuterium incorporation was confirmed by detection of the O-D and C-D stretching peaks with FTIR and quantified by (1)H- and (2)H-NMR. This capability to produce deuterated lignocellulosic biomass under controlled conditions will enhance investigation of cell wall structure and its deconstruction by neutron scattering and NMR techniques.

  16. Urinary excretion of deuterated metabolites in patients with tyrosinemia type I after oral loading with deuterated L-tyrosine

    International Nuclear Information System (INIS)

    Wadman, S.K.; Duran, M.; Ketting, D.; Bruinvis, L.; Sprang, F.J. van; Berger, R.; Smit, G.P.A.; Divry, P.; Farriaux, J.P.; Cartigny, B.

    1983-01-01

    The metabolic fate of orally given deuterated L-tyrosine, 50 mg/kg body weight, was investigated in seven patients with tyrosinemia type I in order to obtain evidence that the primary defect is at the level of fumarylacetoacetase. The absence of fumarylacetoacetase could be proved in liver biopsy specimens obtained from four patients. All patients excreted deuterated succinylacetoacetate and deuterated succinylacetone was detected in six out of seven. The total amount of these compounds was rather low; maximal 8.3% of the dose. The peak of the excretion occurred 3-6 h after loading, indicating an endogenous formation of the metabolites. All patients excreted deuterated 4-hydroxyphenyl acids, probably reflecting secondary 4-hydroxyphenylpyruvate dioxygenase deficiency connected with liver damage. 5. No evidence for other secondary routes of tyrosine metabolism was found. (Auth.)

  17. Effects of deuteration on hematopoiesis in the mouse

    International Nuclear Information System (INIS)

    Adams, W.H.; Adams, D.G.

    1988-01-01

    Mice ingesting 30 to 50% D 2 O (heavy water, deuterium oxide) developed a dose-dependent depression of formed peripheral blood elements in 4 to 9 days. The principal mechanism of anemia and thrombocytopenia is impaired hematopoiesis. Despite pancytopenia in the peripheral blood, bone marrow cellularity and morphology remained normal. Upon replacement of D 2 O with tap water, platelet and neutrophil concentrations returned to normal within 48 to 72 hr. In contrast, blood lymphocyte concentrations remained low for several weeks. B-lymphocytes may be more affected by deuteration than other lymphocyte subsets. In vivo reticuloendothelial cell function, as assessed by 51 Cr-labeled sheep erythrocyte clearance, was unaffected by D 2 O. Although a dose-dependent decrease in fluid intake occurred during deuteration, hematocytopenia was not a consequence of dehydration. In view of the known kinetics of D 2 O in biological systems, the rapid response of myeloid elements to deuteration must be due primarily to the solvent (nonmetabolic) isotope effect. Prolonged deuteration has proven toxic when included in regimens for treatment of neoplasia, including leukemia, in animal models. The present study shows that modulation of hematopoiesis by D 2 O is possible without invoking the toxicities associated with prolonged deuteration

  18. Separation of deuteriated isotopomers of dopamine by ion-pair reversed-phase high-performance liquid chromatography

    International Nuclear Information System (INIS)

    Masters, C.F.; Markey, S.P.; Mefford, I.N.; Duncan, M.W.

    1988-01-01

    The ion-pair reversed-phase separation of dopamine and deuterium-substituted dopamine isotopomers is described. Chromatographic parameters and deuterium isotope effects governing the resolution are examined and compared to the factors regulating the resolution are examined and compared to the factors regulating the resolution of the chemically distinct entities dopamine, norepinephrine, and epinephrine. The potential utility of the [ 2 H 7 ]dopamine, isotopomer as an internal standard for the high-performance liquid chromatography analysis of dopamine is demonstrated by using aluminum oxide extraction prior to chromatographic separation

  19. The VA and VCD spectra of various isotopomers of L-alanine in aqueous solution

    DEFF Research Database (Denmark)

    Abdali, Salim; Jalkanen, Karl J.; Bohr, Henrik

    2002-01-01

    Density functional theory (DFT) at the Becke 3LYP level has been used to calculate the vibrational absorption (VA) and vibrational circular dichroism (VCD) spectra of various deuterated species Of L-alanine. The effect of replacing the methine hydrogen, CH1, the methyl group, CH3, and both...

  20. Deuterated scintillators and their application to neutron spectroscopy

    International Nuclear Information System (INIS)

    Febbraro, M.; Lawrence, C.C.; Zhu, H.; Pierson, B.; Torres-Isea, R.O; Becchetti, F.D.; Kolata, J.J.; Riggins, J.

    2015-01-01

    Deuterated scintillators have been used as a tool for neutron spectroscopy without Neutron Time-of-Flight (n-ToF) for more than 30 years. This article will provide a brief historical overview of the technique and current uses of deuterated scintillators in the UM-DSA and DESCANT arrays. Pulse-shape discrimination and spectrum unfolding with the maximum-likelihood expectation maximization algorithm will be discussed. Experimental unfolding and cross section results from measurements of (d,n), ( 3 He,n) and (α,n) reactions are shown

  1. In vivo dynamic turnover of cerebral 13C isotopomers from [U- 13C]glucose

    Science.gov (United States)

    Xu, Su; Shen, Jun

    2006-10-01

    An INEPT-based 13C MRS method and a cost-effective and widely available 11.7 Tesla 89-mm bore vertical magnet were used to detect dynamic 13C isotopomer turnover from intravenously infused [U- 13C]glucose in a 211 μL voxel located in the adult rat brain. The INEPT-based 1H → 13C polarization transfer method is mostly adiabatic and therefore minimizes signal loss due to B 1 inhomogeneity of the surface coils used. High quality and reproducible data were acquired as a result of combined use of outer volume suppression, ISIS, and the single-shot three-dimensional localization scheme built in the INEPT pulse sequence. Isotopomer patterns of both glutamate C4 at 34.00 ppm and glutamine C4 at 31.38 ppm are dominated first by a doublet originated from labeling at C4 and C5 but not at C3 (with 1JC4C5 = 51 Hz) and then by a quartet originated from labeling at C3, C4, and C5 (with 1JC3C4 = 35 Hz). A lag in the transition of glutamine C4 pattern from doublet-dominance to quartet dominance as compared to glutamate C4 was observed, which provides an independent verification of the precursor-product relationship between neuronal glutamate and glial glutamine and a significant intercompartmental cerebral glutamate-glutamine cycle between neurons and glial cells.

  2. Testing odorant-receptor interaction theories in humans through discrimination of isotopomers

    Directory of Open Access Journals (Sweden)

    Mara Andrione

    2017-12-01

    Full Text Available Odour reception takes place on the olfactory receptor neuron membrane, where molecular receptors interact with volatile odorant molecules. This interaction is classically thought to rely on chemical and structural features of the odorant, e.g. size, shape, functional groups. However, this model does not allow formulating a correct prediction for the smell of an odorant, suggesting that other molecular properties may play a role in the odour transduction process. An alternative model of olfaction maintains that odorant receptors can probe not only the structural and chemical features, but also the molecular vibration spectrum of the odorants. This constitutes the so-called vibration model of olfaction. According to this model, two isotopomers of the same molecule, i.e. two forms of the same molecule, one unaltered and one in which one or more hydrogen atoms are substituted with deuterium – which are therefore structurally and chemically identical, but with different molecular vibration spectra – would interact differently with an olfactory receptor, producing different olfactory perceptions in the brain. Here, we report on a duo-trio discrimination experiment conducted on human subjects, testing isotopomer pairs that have recently been shown to be differentially encoded in the honeybee brain.

  3. Mathematical treatment of isotopologue and isotopomer speciation and fractionation in biochemical kinetics

    Science.gov (United States)

    Maggi, Federico; Riley, William J.

    2010-03-01

    We present a mathematical treatment of the kinetic equations that describe isotopologue and isotopomer speciation and fractionation during enzyme-catalyzed biochemical reactions. These equations, presented here with the name GEBIK (general equations for biochemical isotope kinetics) and GEBIF (general equations for biochemical isotope fractionation), take into account microbial biomass and enzyme dynamics, reaction stoichiometry, isotope substitution number, and isotope location within each isotopologue and isotopomer. In addition to solving the complete GEBIK and GEBIF, we also present and discuss two approximations to the full solutions under the assumption of biomass-free and enzyme steady-state, and under the quasi-steady-state assumption as applied to the complexation rate. The complete and approximate approaches are applied to observations of biological denitrification in soils. Our analysis highlights that the full GEBIK and GEBIF provide a more accurate description of concentrations and isotopic compositions of substrates and products throughout the reaction than do the approximate forms. We demonstrate that the isotopic effects of a biochemical reaction depend, in the most general case, on substrate and complex concentrations and, therefore, the fractionation factor is a function of time. We also demonstrate that inverse isotopic effects can occur for values of the fractionation factor smaller than 1, and that reactions that do not discriminate isotopes do not necessarily imply a fractionation factor equal to 1.

  4. Deuterated fibre Z-pinch on the S-300 generator

    NARCIS (Netherlands)

    Klir, D.; Kravarik, J.; Kubes, P.; Bakshaev, Yu L.; Blinov, P. I.; Chernenko, A. S.; Danko, S. A.; Korolev, V. D.; Ustroev, G. I.; Ivanov, M. I.; Cai, Hongchun

    2006-01-01

    Dense Z-pinch experiments were carried out on the S-300 generator (3.5 MA, 100 ns, 0.15 Omega) at the Kurchatov Institute in Moscow. The experiments were performed at a peak current of 2 MA with a rise time of about 100 ns. The Z-pinch was formed from a deuterated polyethylene fibre of 100 mu m

  5. X-ray structure determination and deuteration of nattokinase

    International Nuclear Information System (INIS)

    Yanagisawa, Yasuhide; Chatake, Toshiyuki; Naito, Sawa; Ohsugi, Tadanori; Yatagai, Chieko; Sumi, Hiroyuki; Kawaguchi, Akio; Chiba-Kamosida, Kaori; Ogawa, Megumi; Adachi, Tatsumi; Morimoto, Yukio

    2013-01-01

    X-ray structure determination and deuteration of nattokinase were performed to facilitate neutron crystallographic analysis. Nattokinase (NK) is a strong fibrinolytic enzyme, which is produced in abundance by Bacillus subtilis natto. Although NK is a member of the subtilisin family, it displays different substrate specificity when compared with other subtilisins. The results of molecular simulations predict that hydrogen arrangements around Ser221 at the active site probably account for the substrate specificity of NK. Therefore, neutron crystallographic analysis should provide valuable information that reveals the enzymatic mechanism of NK. In this report, the X-ray structure of the non-hydrogen form of undeuterated NK was determined, and the preparation of deuterated NK was successfully achieved. The non-hydrogen NK structure was determined at 1.74 Å resolution. The three-dimensional structures of NK and subtilisin E from Bacillus subtilis DB104 are near identical. Deuteration of NK was carried out by cultivating Bacillus subtilis natto in deuterated medium. The D 2 O resistant strain of Bacillus subtilis natto was obtained by successive cultivation rounds, in which the concentration of D 2 O in the medium was gradually increased. NK was purified from the culture medium and its activity was confirmed by the fibrin plate method. The results lay the framework for neutron protein crystallography analysis

  6. X-ray structure determination and deuteration of nattokinase

    Energy Technology Data Exchange (ETDEWEB)

    Yanagisawa, Yasuhide [Chiba Institute of Science, 15-8 Shiomi-cho, Cho-shi, Chiba 288-025 (Japan); Chatake, Toshiyuki [Kyoto University, Asashironishi 2, Kumatori, Osaka 590-0494 (Japan); Naito, Sawa; Ohsugi, Tadanori; Yatagai, Chieko; Sumi, Hiroyuki [Kurashiki University of Science and the Arts, 2640 Nishinoura, Tsurajima-cho, Kurashiki, Okayama 712-8505 (Japan); Kawaguchi, Akio [Kyoto University, Asashironishi 2, Kumatori, Osaka 590-0494 (Japan); Chiba-Kamosida, Kaori [Nippon Advanced Technology Co. Ltd, J-PARC, 2-4 Shirane Shirakata, Tokai, Ibaraki 319-1195 (Japan); Ogawa, Megumi; Adachi, Tatsumi [Chiba Institute of Science, 15-8 Shiomi-cho, Cho-shi, Chiba 288-025 (Japan); Morimoto, Yukio [Kyoto University, Asashironishi 2, Kumatori, Osaka 590-0494 (Japan)

    2013-11-01

    X-ray structure determination and deuteration of nattokinase were performed to facilitate neutron crystallographic analysis. Nattokinase (NK) is a strong fibrinolytic enzyme, which is produced in abundance by Bacillus subtilis natto. Although NK is a member of the subtilisin family, it displays different substrate specificity when compared with other subtilisins. The results of molecular simulations predict that hydrogen arrangements around Ser221 at the active site probably account for the substrate specificity of NK. Therefore, neutron crystallographic analysis should provide valuable information that reveals the enzymatic mechanism of NK. In this report, the X-ray structure of the non-hydrogen form of undeuterated NK was determined, and the preparation of deuterated NK was successfully achieved. The non-hydrogen NK structure was determined at 1.74 Å resolution. The three-dimensional structures of NK and subtilisin E from Bacillus subtilis DB104 are near identical. Deuteration of NK was carried out by cultivating Bacillus subtilis natto in deuterated medium. The D{sub 2}O resistant strain of Bacillus subtilis natto was obtained by successive cultivation rounds, in which the concentration of D{sub 2}O in the medium was gradually increased. NK was purified from the culture medium and its activity was confirmed by the fibrin plate method. The results lay the framework for neutron protein crystallography analysis.

  7. Investigation of four carbon monoxide isotopomers in natural abundance by laser-induced fluorescence in a supersonic jet

    CSIR Research Space (South Africa)

    Du Plessis, A

    2007-01-01

    Full Text Available The four carbon monoxide (CO) isotopomers 12C16O, 13C16O, 12C18O and 12C17O have been detected simultaneously in a CO gas sample of natural isotopic abundance by measuring rovibronic excitation spectra of six vibronic bands in the Fourth Positive...

  8. Detecting climate-change responses of plants and soil organic matter using isotopomers

    Science.gov (United States)

    Schleucher, Jürgen; Ehlers, Ina; Segura, Javier; Haei, Mahsa; Augusti, Angela; Köhler, Iris; Zuidema, Pieter; Nilsson, Mats; Öquist, Mats

    2015-04-01

    Responses of vegetation and soils to environmental changes will strongly influence future climate, and responses on century time scales are most important for feedbacks on the carbon cycle, climate models, prediction of crop productivity, and for adaptation to climate change. That plants respond to increasing CO2 on century time scales has been proven by changes in stomatal index, but very little is known beyond this. In soil, the complexity of soil organic matter (SOM) has hampered a sufficient understanding of the temperature sensitivity of SOM turnover. Here we present new stable isotope methodology that allows detecting shifts in metabolism on long time scales, and elucidating SOM turnover on the molecular level. Compound-specific isotope analysis measures isotope ratios of defined metabolites, but as average of the entire molecule. Here we demonstrate how much more detailed information can be obtained from analyses of intramolecular distributions of stable isotopes, so-called isotopomer abundances. As key tool, we use nuclear magnetic resonance (NMR) spectroscopy, which allows detecting isotope abundance with intramolecular resolution and without risk for isotope fractionation during analysis. Enzyme isotope fractionations create non-random isotopomer patterns in biochemical metabolites. At natural isotope abundance, these patterns continuously store metabolic information. We present a strategy how these patterns can be used as to extract signals on plant physiology, climate variables, and their interactions. Applied in retrospective analyses to herbarium samples and tree-ring series, we detect century-time-scale metabolic changes in response to increasing atmospheric CO2, with no evidence for acclimatory reactions by the plants. In trees, the increase in photosynthesis expected from increasing CO2 ("CO2 fertilization) was diminished by increasing temperatures, which resolves the discrepancy between expected increases in photosynthesis and commonly observed

  9. Study of Stationary Phase Metabolism Via Isotopomer Analysis of Amino Acids from an Isolated Protein

    Energy Technology Data Exchange (ETDEWEB)

    Shaikh, AfshanS.; Tang, YinjieJ.; Mukhopadhyay, Aindrila; Martin, Hector Garcia; Gin, Jennifer; Benke, Peter; Keasling, Jay D.

    2009-09-14

    Microbial production of many commercially important secondary metabolites occurs during stationary phase, and methods to measure metabolic flux during this growth phase would be valuable. Metabolic flux analysis is often based on isotopomer information from proteinogenic amino acids. As such, flux analysis primarily reflects the metabolism pertinent to the growth phase during which most proteins are synthesized. To investigate central metabolism and amino acids synthesis activity during stationary phase, addition of fully 13C-labeled glucose followed by induction of green fluorescent protein (GFP) expression during stationary phase was used. Our results indicate that Escherichia coli was able to produce new proteins (i.e., GFP) in the stationary phase, and the amino acids in GFP were mostly from degraded proteins synthesized during the exponential growth phase. Among amino acid biosynthetic pathways, only those for serine, alanine, glutamate/glutamine, and aspartate/asparagine had significant activity during the stationary phase.

  10. Catalytic Stereoinversion of L-Alanine to Deuterated D-Alanine.

    Science.gov (United States)

    Moozeh, Kimia; So, Soon Mog; Chin, Jik

    2015-08-03

    A combination of an achiral pyridoxal analogue and a chiral base has been developed for catalytic deuteration of L-alanine with inversion of stereochemistry to give deuterated D-alanine under mild conditions (neutral pD and 25 °C) without the use of any protecting groups. This system can also be used for catalytic deuteration of D-alanine with retention of stereochemistry to give deuterated D-alanine. Thus a racemic mixture of alanine can be catalytically deuterated to give an enantiomeric excess of deuterated D-alanine. While catalytic deracemization of alanine is forbidden by the second law of thermodynamics, this system can be used for catalytic deracemization of alanine with deuteration. Such green and biomimetic approach to catalytic stereocontrol provides insights into efficient amino acid transformations. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Grasland Stable Isotope Flux Measurements: Three Isotopomers of Carbon Dioxide Measured by QCL Spectroscopy

    Science.gov (United States)

    Zeeman, M. J.; Tuzson, B.; Eugster, W.; Werner, R. A.; Buchmann, N.; Emmenegger, L.

    2007-12-01

    To improve our understanding of greenhouse gas dynamics of managed ecosystems such as grasslands, we not only need to investigate the effects of management (e.g., grass cuts) and weather events (e.g., rainy days) on carbon dioxide fluxes, but also need to increase the time resolution of our measurements. Thus, for the first time, we assessed respiration and assimilation fluxes with high time resolution (5Hz) stable isotope measurements at an intensively managed farmland in Switzerland (Chamau, 400m ASL). Two different methods were used to quantify fluxes of carbon dioxide and associated fluxes of stable carbon isotopes: (1) the flux gradient method, and (2) the eddy covariance method. During a week long intensive measurement campaign, we (1) measured mixing ratios of carbon dioxide isotopomers (12C16O2, 12C16O18O, 13C16O2) with a Quantum Cascade Laser (QCL, Aerodyne Inc.) spectroscope and (2) collected air samples for isotope analyses (13C/12C) and (18O/16O) of carbon dioxide by Isotope Ratio Mass Spectrometry (IRMS, Finnigan) every two hours, concurrently along a height profile (z = 0.05; 0.10; 0.31; 2.15m). In the following week, the QCL setup was used for closed-path eddy covariance flux measurement of the carbon dioxide isotopomers, with the air inlet located next to an open-path Infra Red Gas Analyzers (IRGA, LiCor 7500) used simultaneously for carbon dioxide measurements. During this second week, an area of grass inside the footprint was cut and harvested after several days. The first results of in-field continuous QCL measurements of carbon dioxide mixing ratios and their stable isotopic ratios show good agreement with IRGA measurements and isotope analysis of flask samples by IRMS. Thus, QCL spectroscopy is a very promising tool for stable isotope flux investigations.

  12. Multilayer Formation and Evaporation of Deuterated Ices in Prestellar and Protostellar Cores

    Science.gov (United States)

    Taquet, Vianney; Charnley, Steven B.; Sipilä, Olli

    2014-08-01

    Extremely large deuteration of several molecules has been observed toward prestellar cores and low-mass protostars for a decade. New observations performed toward low-mass protostars suggest that water presents a lower deuteration in the warm inner gas than in the cold external envelope. We coupled a gas-grain astrochemical model with a one-dimensional model of a collapsing core to properly follow the formation and the deuteration of interstellar ices as well as their subsequent evaporation in the low-mass protostellar envelopes with the aim of interpreting the spatial and temporal evolutions of their deuteration. The astrochemical model follows the formation and the evaporation of ices with a multilayer approach and also includes a state-of-the-art deuterated chemical network by taking the spin states of H2 and light ions into account. Because of their slow formation, interstellar ices are chemically heterogeneous and show an increase of their deuterium fractionation toward the surface. The differentiation of the deuteration in ices induces an evolution of the deuteration within protostellar envelopes. The warm inner region is poorly deuterated because it includes the whole molecular content of ices, while the deuteration predicted in the cold external envelope scales with the highly deuterated surface of ices. We are able to reproduce the observed evolution of water deuteration within protostellar envelopes, but we are still unable to predict the super-high deuteration observed for formaldehyde and methanol. Finally, the extension of this study to the deuteration of complex organics, important for the prebiotic chemistry, shows good agreement with the observations, suggesting that we can use the deuteration to retrace their mechanisms and their moments of formation.

  13. Multilayer formation and evaporation of deuterated ices in prestellar and protostellar cores

    International Nuclear Information System (INIS)

    Taquet, Vianney; Charnley, Steven B.; Sipilä, Olli

    2014-01-01

    Extremely large deuteration of several molecules has been observed toward prestellar cores and low-mass protostars for a decade. New observations performed toward low-mass protostars suggest that water presents a lower deuteration in the warm inner gas than in the cold external envelope. We coupled a gas-grain astrochemical model with a one-dimensional model of a collapsing core to properly follow the formation and the deuteration of interstellar ices as well as their subsequent evaporation in the low-mass protostellar envelopes with the aim of interpreting the spatial and temporal evolutions of their deuteration. The astrochemical model follows the formation and the evaporation of ices with a multilayer approach and also includes a state-of-the-art deuterated chemical network by taking the spin states of H 2 and light ions into account. Because of their slow formation, interstellar ices are chemically heterogeneous and show an increase of their deuterium fractionation toward the surface. The differentiation of the deuteration in ices induces an evolution of the deuteration within protostellar envelopes. The warm inner region is poorly deuterated because it includes the whole molecular content of ices, while the deuteration predicted in the cold external envelope scales with the highly deuterated surface of ices. We are able to reproduce the observed evolution of water deuteration within protostellar envelopes, but we are still unable to predict the super-high deuteration observed for formaldehyde and methanol. Finally, the extension of this study to the deuteration of complex organics, important for the prebiotic chemistry, shows good agreement with the observations, suggesting that we can use the deuteration to retrace their mechanisms and their moments of formation.

  14. Multilayer formation and evaporation of deuterated ices in prestellar and protostellar cores

    Energy Technology Data Exchange (ETDEWEB)

    Taquet, Vianney; Charnley, Steven B. [Astrochemistry Laboratory and The Goddard Center for Astrobiology, Mailstop 691, NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20770 (United States); Sipilä, Olli [Department of Physics, University of Helsinki, P.O. Box 64, FI-00014 Helsinki (Finland)

    2014-08-10

    Extremely large deuteration of several molecules has been observed toward prestellar cores and low-mass protostars for a decade. New observations performed toward low-mass protostars suggest that water presents a lower deuteration in the warm inner gas than in the cold external envelope. We coupled a gas-grain astrochemical model with a one-dimensional model of a collapsing core to properly follow the formation and the deuteration of interstellar ices as well as their subsequent evaporation in the low-mass protostellar envelopes with the aim of interpreting the spatial and temporal evolutions of their deuteration. The astrochemical model follows the formation and the evaporation of ices with a multilayer approach and also includes a state-of-the-art deuterated chemical network by taking the spin states of H{sub 2} and light ions into account. Because of their slow formation, interstellar ices are chemically heterogeneous and show an increase of their deuterium fractionation toward the surface. The differentiation of the deuteration in ices induces an evolution of the deuteration within protostellar envelopes. The warm inner region is poorly deuterated because it includes the whole molecular content of ices, while the deuteration predicted in the cold external envelope scales with the highly deuterated surface of ices. We are able to reproduce the observed evolution of water deuteration within protostellar envelopes, but we are still unable to predict the super-high deuteration observed for formaldehyde and methanol. Finally, the extension of this study to the deuteration of complex organics, important for the prebiotic chemistry, shows good agreement with the observations, suggesting that we can use the deuteration to retrace their mechanisms and their moments of formation.

  15. Study of the deuterated albumin by FT-IR spectroscopy

    International Nuclear Information System (INIS)

    Stoenescu, Daniela; Sahini, V.E.

    2000-01-01

    The albumin is a protein from the soluble or corpuscular protein class, which exists in cells, in dissolved state or in form of a hydrated gel. Proteins are essential constituents beside water, inorganic salts, lipids, carbon hydrates, vitamins, enzymes. The albumin is also a protein soluble in water and in diluted electrolyte solutions (acids, bases and salts). The investigation of the vibration isotopic effect has a great importance both for the diatomic molecules and for the polyatomic molecules. This paper is the first from a series of works which are intended to study the physico-chemical properties of the deuterated albumin and of the albumin solutions in heavy water by an isotopic exchange method. To put in evidence H-D exchange, the FT-IR spectroscopy is used when the deuterated albumin has different layer thickness. It is also of interest to elucidate the isotopic exchange between the hydrogen and oxygen atoms in bovine serum albumin macromolecules. (authors)

  16. Characterization and production and consumption processes of N2O emitted from temperate agricultural soils determined via isotopomer ratio analysis

    Science.gov (United States)

    Toyoda, Sakae; Yano, Midori; Nishimura, Sei-Ichi; Akiyama, Hiroko; Hayakawa, Atsushi; Koba, Keisuke; Sudo, Shigeto; Yagi, Kazuyuki; Makabe, Akiko; Tobari, Yoshifumi; Ogawa, Nanako O.; Ohkouchi, Naohiko; Yamada, Keita; Yoshida, Naohiro

    2011-06-01

    Isotopomer ratios of N2O (bulk nitrogen and oxygen isotope ratios, δ15Nbulk and δ18O, and intramolecular 15N site preference, SP) are useful parameters that characterize sources of this greenhouse gas and also provide insight into production and consumption mechanisms. We measured isotopomer ratios of N2O emitted from typical Japanese agricultural soils (Fluvisols and Andisols) planted with rice, wheat, soybean, and vegetables, and treated with synthetic (urea or ammonium) and organic (poultry manure) fertilizers. The results were analyzed using a previously reported isotopomeric N2O signature produced by nitrifying/denitrifying bacteria and a characteristic relationship between δ15Nbulk and SP during N2O reduction by denitrifying bacteria. Relative contributions from nitrification (hydroxylamine oxidation) and denitrification (nitrite reduction) to gross N2O production deduced from the analysis depended on soil type and fertilizer. The contribution from nitrification was relatively high (40%-70%) in Andisols amended with synthetic ammonium fertilizer, while denitrification was dominant (50%-90%) in the same soils amended with poultry manure during the period when N2O production occurred in the surface layer. This information on production processes is in accordance with that obtained from flux/concentration analysis of N2O and soil inorganic nitrogen. However, isotopomer analysis further revealed that partial reduction of N2O was pronounced in high-bulk density, alluvial soil (Fluvisol) compared to low-bulk density, volcanic ash soil (Andisol), and that the observed difference in N2O flux between normal and pelleted manure could have resulted from a similar mechanism with different rates of gross production and gross consumption. The isotopomeric analysis is based on data from pure culture bacteria and would be improved by further studies on in situ biological processes in soils including those by fungi. When flux/concentration-weighted average isotopomer

  17. Catalytic hydrogenation of carbonyl group for deuterated compound production

    International Nuclear Information System (INIS)

    Gluhoi, C. Andreea; Marginean, P.; Lazar, Diana; Almasan, V.

    1999-01-01

    The total deuterated isopropyl alcohol can be produced starting from acetone. The developed technology comprises two steps: Deuteration of acetone by H/D isotopic exchange between acetone and heavy water in homogeneous catalysis. Reduction of the deuterated acetone with deuterium in presence of a metal/support catalyst. H/D isotopic exchange reaction of the H atoms from CH 3 groups is easy to occur because carbonyl group weakens C-H bond (ceto-enolyc tautomery). The big difference between boiling points of acetone and water permits an easy separation of acetone by distillation method. The reduction of acetone with deuterium was performed in a dynamic reactor by passing a deuterium flow saturated with acetone vapour through a supported nickel catalyst bed. The reaction products were analysed on-line using a flame ionisation detector. The supported nickel catalysts were checked for this reaction. By using nickel over different supports the selectivity for isopropyl alcohol was about 100%. The propane was detected only as traces. The catalytic activity depends strongly on the support nature: the Ni/SiO 2 is less active, while the Ni/TiO 2 presents the larger value for the intrinsic activity. (authors)

  18. X-ray structure determination and deuteration of nattokinase.

    Science.gov (United States)

    Yanagisawa, Yasuhide; Chatake, Toshiyuki; Naito, Sawa; Ohsugi, Tadanori; Yatagai, Chieko; Sumi, Hiroyuki; Kawaguchi, Akio; Chiba-Kamosida, Kaori; Ogawa, Megumi; Adachi, Tatsumi; Morimoto, Yukio

    2013-11-01

    Nattokinase (NK) is a strong fibrinolytic enzyme, which is produced in abundance by Bacillus subtilis natto. Although NK is a member of the subtilisin family, it displays different substrate specificity when compared with other subtilisins. The results of molecular simulations predict that hydrogen arrangements around Ser221 at the active site probably account for the substrate specificity of NK. Therefore, neutron crystallographic analysis should provide valuable information that reveals the enzymatic mechanism of NK. In this report, the X-ray structure of the non-hydrogen form of undeuterated NK was determined, and the preparation of deuterated NK was successfully achieved. The non-hydrogen NK structure was determined at 1.74 Å resolution. The three-dimensional structures of NK and subtilisin E from Bacillus subtilis DB104 are near identical. Deuteration of NK was carried out by cultivating Bacillus subtilis natto in deuterated medium. The D2O resistant strain of Bacillus subtilis natto was obtained by successive cultivation rounds, in which the concentration of D2O in the medium was gradually increased. NK was purified from the culture medium and its activity was confirmed by the fibrin plate method. The results lay the framework for neutron protein crystallography analysis.

  19. Vacuum ultraviolet photochemistry of CH4 and isotopomers. II. Product channel fields and absorption spectra

    International Nuclear Information System (INIS)

    Wang, Jen-Han; Liu, Kopin; Min, Zhiyuan; Su, Hongmei; Bersohn, Richard; Preses, Jack; Larese, John Z.

    2000-01-01

    In part I of this work the relative velocities and anisotropies of the atomic H and D fragments from methane photolysis at 10.2 eV were measured. In this paper the relative abundance of the methyl and methylene fragments are reported. A complete set of quantum yields for the different photodissociation channels of each isotopomer is obtained by combining the two sets of data. Previously it was found that H atoms are almost four times more likely than D atoms to be ejected; now it is found that hydrogen molecule photofragments are much richer in H atoms than in D. Overall, the heavier D atoms are more likely than the H atoms to remain attached to the carbon atom. An implication for astrophysics is discussed. The VUV absorption spectra of CH 4 and CH 3 D are almost identical both at room temperature and 75 K. There is, as expected, no variation in the absorption spectrum with temperature. Evidence is given that all or almost all of the methylene is produced in the a 1 A 1 and not in the ground 3 B 1 state. (c) 2000 American Institute of Physics

  20. A simplified calculation procedure for mass isotopomer distribution analysis (MIDA) based on multiple linear regression.

    Science.gov (United States)

    Fernández-Fernández, Mario; Rodríguez-González, Pablo; García Alonso, J Ignacio

    2016-10-01

    We have developed a novel, rapid and easy calculation procedure for Mass Isotopomer Distribution Analysis based on multiple linear regression which allows the simultaneous calculation of the precursor pool enrichment and the fraction of newly synthesized labelled proteins (fractional synthesis) using linear algebra. To test this approach, we used the peptide RGGGLK as a model tryptic peptide containing three subunits of glycine. We selected glycine labelled in two 13 C atoms ( 13 C 2 -glycine) as labelled amino acid to demonstrate that spectral overlap is not a problem in the proposed methodology. The developed methodology was tested first in vitro by changing the precursor pool enrichment from 10 to 40% of 13 C 2 -glycine. Secondly, a simulated in vivo synthesis of proteins was designed by combining the natural abundance RGGGLK peptide and 10 or 20% 13 C 2 -glycine at 1 : 1, 1 : 3 and 3 : 1 ratios. Precursor pool enrichments and fractional synthesis values were calculated with satisfactory precision and accuracy using a simple spreadsheet. This novel approach can provide a relatively rapid and easy means to measure protein turnover based on stable isotope tracers. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Infrared and Raman Spectra of and Isotopomers: A DFT-PT2 Anharmonic Study

    Directory of Open Access Journals (Sweden)

    Andrea Alparone

    2013-01-01

    Full Text Available IR and Raman spectra of selenophene and of its perdeuterated isotopomer have been obtained in gas phase through density-functional theory (DFT computations. Vibrational wavenumbers have been calculated using harmonic and anharmonic second-order perturbation theory (PT2 procedures with the B3LYP method and the 6-311 basis set. Anharmonic overtones have been determined by means of the PT2 method. The introduction of anharmonic terms decreases the harmonic wavenumbers, giving a significantly better agreement with the experimental data. The most significant anharmonic effects occur for the C–H and C–D stretching modes, the observed H/D isotopic wavenumber redshifts being satisfactorily reproduced by the PT2 computations within 6–20 cm−1 (1–3%. In the spectral region between 500 cm−1 and 1500 cm−1, the IR spectra are dominated by the out-of-plane C–H (C–D bending transition, whereas the Raman spectra are mainly characterized by a strong peak mainly attributed to the C=C + C–C bonds stretching vibration with the contribution of the in-plane C–H (C–D bending deformation. The current results confirm that the PT2 approach combined with the B3LYP/6-311 level of calculation is a satisfactory choice for predicting vibrational spectra of cyclic molecules.

  2. Metabolic Effects of Hypoxia in Colorectal Cancer by 13C NMR Isotopomer Analysis

    Directory of Open Access Journals (Sweden)

    Ana M. Abrantes

    2014-01-01

    Full Text Available 13C NMR isotopomer analysis was used to characterize intermediary metabolism in three colorectal cancer cell lines (WiDr, LS1034, and C2BBe1 and determine the “metabolic remodeling” that occurs under hypoxia. Under normoxia, the three colorectal cancer cell lines present high rates of lactate production and can be seen as “Warburg” like cancer cells independently of substrate availability, since such profile was dominant at both high and low glucose media contents. The LS1034 was the less glycolytic of the three cell lines and was the most affected by the event of hypoxia, raising abruptly glucose consumption and lactate production. The other two colorectal cell lines, WiDr and C2BBe1, adapted better to hypoxia and were able to maintain their oxidative fluxes even at the very low levels of oxygen. These differential metabolic behaviors of the three colorectal cell lines show how important an adequate knowledge of the “metabolic remodeling” that follows a given cancer treatment is towards the correct (redesign of therapeutic strategies against cancer.

  3. Isotopomer analysis of lipid biosynthesis by high resolution mass spectrometry and NMR

    Energy Technology Data Exchange (ETDEWEB)

    Lane, Andrew N., E-mail: anlane01@louisville.edu [JG Brown Cancer Center, 529 S. Jackson Street, Louisville, KY 40202 (United States); Center for Regulatory and Environmental Analytical Metabolomics (CREAM), University of Louisville, Louisville, KY (United States); Fan, Teresa W.-M. [JG Brown Cancer Center, 529 S. Jackson Street, Louisville, KY 40202 (United States); Center for Regulatory and Environmental Analytical Metabolomics (CREAM), University of Louisville, Louisville, KY (United States); Department of Chemistry, University of Louisville, Louisville, KY 40292 (United States); Xie, Zhengzhi; Moseley, Hunter N.B.; Higashi, Richard M. [Center for Regulatory and Environmental Analytical Metabolomics (CREAM), University of Louisville, Louisville, KY (United States); Department of Chemistry, University of Louisville, Louisville, KY 40292 (United States)

    2009-10-05

    We have coupled 2D-NMR and infusion FT-ICR-MS with computer-assisted assignment to profile {sup 13}C-isotopologues of glycerophospholipids (GPL) directly in crude cell extracts, resulting in very high information throughput of >3000 isobaric molecules in a few minutes. A mass accuracy of better than 1 ppm combined with a resolution of 100,000 at the measured m/z was required to distinguish isotopomers from other GPL structures. Isotopologue analysis of GPLs extracted from LCC2 breast cancer cells grown on [U-{sup 13}C]-glucose provided a rich trove of information about the biosynthesis and turnover of the GPLs. The isotopologue intensity ratios from the FT-ICR-MS were accurate to {approx}1% or better based on natural abundance background, and depended on the signal-to-nose ratio. The time course of incorporation of {sup 13}C from [U-{sup 13}C]-glucose into a particular phosphatidylcholine was analyzed in detail, to provide a quantitative measure of the sizes of glycerol, acetyl CoA and total GPL pools in growing LCC2 cells. Independent and complementary analysis of the positional {sup 13}C enrichment in the glycerol and fatty acyl chains obtained from high resolution 2D NMR was used to verify key aspects of the model. This technology enables simple and rapid sample preparation, has rapid analysis, and is generally applicable to unfractionated GPLs of almost any head group, and to mixtures of other classes of metabolites.

  4. Isotopomer analysis of lipid biosynthesis by high resolution mass spectrometry and NMR

    International Nuclear Information System (INIS)

    Lane, Andrew N.; Fan, Teresa W.-M.; Xie, Zhengzhi; Moseley, Hunter N.B.; Higashi, Richard M.

    2009-01-01

    We have coupled 2D-NMR and infusion FT-ICR-MS with computer-assisted assignment to profile 13 C-isotopologues of glycerophospholipids (GPL) directly in crude cell extracts, resulting in very high information throughput of >3000 isobaric molecules in a few minutes. A mass accuracy of better than 1 ppm combined with a resolution of 100,000 at the measured m/z was required to distinguish isotopomers from other GPL structures. Isotopologue analysis of GPLs extracted from LCC2 breast cancer cells grown on [U- 13 C]-glucose provided a rich trove of information about the biosynthesis and turnover of the GPLs. The isotopologue intensity ratios from the FT-ICR-MS were accurate to ∼1% or better based on natural abundance background, and depended on the signal-to-nose ratio. The time course of incorporation of 13 C from [U- 13 C]-glucose into a particular phosphatidylcholine was analyzed in detail, to provide a quantitative measure of the sizes of glycerol, acetyl CoA and total GPL pools in growing LCC2 cells. Independent and complementary analysis of the positional 13 C enrichment in the glycerol and fatty acyl chains obtained from high resolution 2D NMR was used to verify key aspects of the model. This technology enables simple and rapid sample preparation, has rapid analysis, and is generally applicable to unfractionated GPLs of almost any head group, and to mixtures of other classes of metabolites.

  5. Electrical conductivity measurement on DKDP Crystals with different deuterated degrees

    International Nuclear Information System (INIS)

    Liu, Baoan; Yin, Xin; Xu, Mingxia; Ji, Shaohua; Zhu, Lili; Zhang, Lisong; Sun, Xun; Xu, Xinguang; Zhao, Minglei; Zhang, Qinghua

    2012-01-01

    Ten DKDP single crystals with deuterated degrees ranging from 0 to 90 % were grown by a rapid growth method. The electrical conductivities of these crystals were measured along a and c directions at room temperature. The electrical conductivity increases with the increase for deuterium content. Also, the electrical conductivities of certain crystals were measured at various temperatures ranging from 20 to 130 C. The values of activation energy decrease as the increase of deuterium content. The present study indicates that the deuterium tunneling frequency is smaller than that of hydrogen, which may be the reason why the variation of electrical conductivity happens after the substitution of hydrogen for deuterium in KDP crystal. (orig.)

  6. Deuterated-decaborane using boronization on JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Yagyu, Jun-ichi; Arai, Takashi; Kaminaga, Atsushi; Miyata, Katsuyuki [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Arai, Masaru [Kaihatsu Denki Co., Ltd., Tokyo (Japan)

    2001-03-01

    In JT-60U, boronization using hydride-decaborane (B{sub 10}H{sub 14}) vaporization has been conducted for the first wall conditioning. Compared to other discharge cleaning (DC), boronization is claimed to be efficient in reduction of oxygen impurities and hydrogen recycling in plasma. However, there are some problems in reduction of hydrogen included in boron film and stabilization of DC glow discharge during the boronization. To solve these problems, a new boronization method using deuterated-decaborane (B{sub 10}D{sub 14}) was adopted instead of the conventional hydride-decaborane. As a result, hydrogen content in the boron film decreased clearly and discharge conditioning shots, for decreasing hydrogen content in plasmas, after the boronization were reduced to 1/10 in comparison to the conventional process. Furthermore, DC glow discharge became stable, with only helium carrier gas, and it was possible to save 30 hours in maximum of the time necessary to boronization. It is shown that the boronization using deuterated-decaborane is very efficient and effective method for the first wall conditioning. (author)

  7. DEUTERIUM FRACTIONATION DURING AMINO ACID FORMATION BY PHOTOLYSIS OF INTERSTELLAR ICE ANALOGS CONTAINING DEUTERATED METHANOL

    Energy Technology Data Exchange (ETDEWEB)

    Oba, Yasuhiro; Watanabe, Naoki; Kouchi, Akira [Institute of Low Temperature Science, Hokkaido University, N19W8, Kita-ku, Sapporo, Hokkaido 060-0819 (Japan); Takano, Yoshinori, E-mail: oba@lowtem.hokudai.ac.jp [Department of Biogeochemistry, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), 2-15 Natsushima, Yokosuka, Kanagawa 237-0061 (Japan)

    2016-08-10

    Deuterium (D) atoms in interstellar deuterated methanol might be distributed into complex organic molecules through molecular evolution by photochemical reactions in interstellar grains. In this study, we use a state-of-the-art high-resolution mass spectrometer coupled with a high-performance liquid chromatography system to quantitatively analyze amino acids and their deuterated isotopologues formed by the photolysis of interstellar ice analogs containing singly deuterated methanol CH{sub 2}DOH at 10 K. Five amino acids (glycine, α -alanine, β -alanine, sarcosine, and serine) and their deuterated isotopologues whose D atoms are bound to carbon atoms are detected in organic residues formed by photolysis followed by warming up to room temperature. The abundances of singly deuterated amino acids are in the range of 0.3–1.1 relative to each nondeuterated counterpart, and the relative abundances of doubly and triply deuterated species decrease with an increasing number of D atoms in a molecule. The abundances of amino acids increase by a factor of more than five upon the hydrolysis of the organic residues, leading to decreases in the relative abundances of deuterated species for α -alanine and β -alanine. On the other hand, the relative abundances of the deuterated isotopologues of the other three amino acids did not decrease upon hydrolysis, indicating different formation mechanisms of these two groups upon hydrolysis. The present study facilitates both qualitative and quantitative evaluations of D fractionation during molecular evolution in the interstellar medium.

  8. DEUTERIUM FRACTIONATION DURING AMINO ACID FORMATION BY PHOTOLYSIS OF INTERSTELLAR ICE ANALOGS CONTAINING DEUTERATED METHANOL

    International Nuclear Information System (INIS)

    Oba, Yasuhiro; Watanabe, Naoki; Kouchi, Akira; Takano, Yoshinori

    2016-01-01

    Deuterium (D) atoms in interstellar deuterated methanol might be distributed into complex organic molecules through molecular evolution by photochemical reactions in interstellar grains. In this study, we use a state-of-the-art high-resolution mass spectrometer coupled with a high-performance liquid chromatography system to quantitatively analyze amino acids and their deuterated isotopologues formed by the photolysis of interstellar ice analogs containing singly deuterated methanol CH 2 DOH at 10 K. Five amino acids (glycine, α -alanine, β -alanine, sarcosine, and serine) and their deuterated isotopologues whose D atoms are bound to carbon atoms are detected in organic residues formed by photolysis followed by warming up to room temperature. The abundances of singly deuterated amino acids are in the range of 0.3–1.1 relative to each nondeuterated counterpart, and the relative abundances of doubly and triply deuterated species decrease with an increasing number of D atoms in a molecule. The abundances of amino acids increase by a factor of more than five upon the hydrolysis of the organic residues, leading to decreases in the relative abundances of deuterated species for α -alanine and β -alanine. On the other hand, the relative abundances of the deuterated isotopologues of the other three amino acids did not decrease upon hydrolysis, indicating different formation mechanisms of these two groups upon hydrolysis. The present study facilitates both qualitative and quantitative evaluations of D fractionation during molecular evolution in the interstellar medium.

  9. Specific acid catalyzed deuteration of the acetyl groups of 2,4-diacetyldeuterohemin-OMe

    International Nuclear Information System (INIS)

    Oster, O.; Neireiter, G.W.; Gurd, F.R.N.

    1975-01-01

    The methyl group of the acetyl groups in 2,4-diacetyldeuterohemin-OMe has been selectively deuterated. After removal of the iron, D 6 -2,4-diacetyl-deuteroporphyrin-OMe can be reduced to the corresponding hematoporphyrin and subsequent dehydration gives deuterated vinylic groups for protoporphyrin IX-OMe. (orig.) [de

  10. Spatial Variations in N2O Concentration and Isotopomer Composition off the Peru Coast

    Science.gov (United States)

    Bourbonnais, A.; Letscher, R. T.; Kock, A.; Bange, H. W.; Altabet, M. A.

    2016-02-01

    Nitrous oxide (N2O) is a potent greenhouse gas and stratospheric ozone depleting substance. The ocean is an important source of N2O to the atmosphere, accounting for up to about 30% of total emissions. However, the factors controlling N2O production and consumption in oceanic environments are still not understood nor constrained. N2O is a by-product of aerobic nitrification, and is formed by two different pathways: 1) the decomposition of hydroxylamine, an intermediate during ammonium oxidation to nitrite, or 2) the reduction of nitrite to N2O (nitrifier-denitrification). N2O is also an intermediate during denitrification under anoxic conditions. In this study, we measured N2O concentrations and isotopomer ratios, as well as O2, nutrient and biogenic N2 concentrations and the isotopic compositions of nitrate, nitrite and biogenic N2 at several coastal stations during two cruises off the Peru coast (6-14°S, 75-81°W) in December 2012 and January 2013. [N2O] varied from below equilibrium values in the OMZ to up to 238 nmol L-1 at 11 m depth at one of the shallowest stations. The isotopic composition of N2O (bulk δ15N: -5 to 30‰, δ18O: 41 to 95‰, and Site Preference: -3 to 65‰) also varied widely, with important differences between stations. Our results show a strong spatial heterogeneity in the mechanisms controlling N2O production and consumption in coastal upwelling regions, which should be taken into account in oceanic N2O models. We will discuss the contributions from different N2O production processes responsible for the observed extreme N2O accumulations.

  11. Elucidating Turnover Pathways of Bioactive Small Molecules by Isotopomer Analysis: The Persistent Organic Pollutant DDT

    Science.gov (United States)

    Ehlers, Ina; Betson, Tatiana R.; Vetter, Walter; Schleucher, Jürgen

    2014-01-01

    The persistent organic pollutant DDT (1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane) is still indispensable in the fight against malaria, although DDT and related compounds pose toxicological hazards. Technical DDT contains the dichloro congener DDD (1-chloro-4-[2,2-dichloro-1-(4-chlorophenyl)ethyl]benzene) as by-product, but DDD is also formed by reductive degradation of DDT in the environment. To differentiate between DDD formation pathways, we applied deuterium NMR spectroscopy to measure intramolecular deuterium distributions (2H isotopomer abundances) of DDT and DDD. DDD formed in the technical DDT synthesis was strongly deuterium-enriched at one intramolecular position, which we traced back to 2H/1H fractionation of a chlorination step in the technical synthesis. In contrast, DDD formed by reductive degradation was strongly depleted at the same position, which was due to the incorporation of 2H-depleted hydride equivalents during reductive degradation. Thus, intramolecular isotope distributions give mechanistic information on reaction pathways, and explain a puzzling difference in the whole-molecule 2H/1H ratio between DDT and DDD. In general, our results highlight that intramolecular isotope distributions are essential to interpret whole-molecule isotope ratios. Intramolecular isotope information allows distinguishing pathways of DDD formation, which is important to identify polluters or to assess DDT turnover in the environment. Because intramolecular isotope data directly reflect isotope fractionation of individual chemical reactions, they are broadly applicable to elucidate transformation pathways of small bioactive molecules in chemistry, physiology and environmental science. PMID:25350380

  12. The synthesis of the 2H, 3H, and 14C-isotopomers of 2'-deoxy-2',2'-difluorocytidine hydrochloride, an anti-tumor compound

    International Nuclear Information System (INIS)

    Wheeler, W.J.; Mabry, T.E.; Jones, C.D.

    1991-01-01

    The 2 H, 3 H, and 14 C-isotopomers of 2'-deoxy-2', 2'-difluorocytidine hydrochloride (gemcitabine hydrochloride) have been synthesized in two radiochemical steps from the reaction of bis-trimethylsilylcytosine-[2- 14 C] and 3,5-O-bis-benzoyl-1-O-methanesulfonyl-2-deoxy-2,2-difluororibose. A mixture of anomers of 3',5'-dibenzoyl-2'-deoxy-2',2'-difluorocytidine or its 14 C-isotopomer were obtained which were readily separated by crystallization from ethyl acetate. Deprotection using methanolic ammonia yielded the target compound. The 2 H and 3 H-isotopomers were prepared by deuterium (or tritium) gas hydrogenolysis of 5-iodo-2'-deoxy-2',2'-difluorocytidine. (author)

  13. Incoherent neutron scattering in acetanilide and three deuterated derivatives

    Science.gov (United States)

    Barthes, Mariette; Almairac, Robert; Sauvajol, Jean-Louis; Moret, Jacques; Currat, Roland; Dianoux, José

    1991-03-01

    Incoherent-neutron-scattering measurements of the vibrational density of states of acetanilide and three deuterated derivatives are presented. These data allow one to identify an intense maximum, assigned to the N-H out-of-plane bending mode. The data display the specific behavior of the methyl torsional modes: large isotopic shift and strong low-temperature intensity; confirm our previous inelastic-neutron-scattering studies, indicating no obvious anomalies in the range of frequency of the acoustic phonons. In addition, the data show the existence of thermally activated quasielastic scattering above 100 K, assigned to the random diffusive motion of the methyl protons. These results are discussed in the light of recent theoretical models proposed to explain the anomalous optical properties of this crystal.

  14. MID Max: LC–MS/MS Method for Measuring the Precursor and Product Mass Isotopomer Distributions of Metabolic Intermediates and Cofactors for Metabolic Flux Analysis Applications

    DEFF Research Database (Denmark)

    McCloskey, Douglas; Young, Jamey D.; Xu, Sibei

    2016-01-01

    The analytical challenges to acquire accurate isotopic data of intracellular metabolic intermediates for stationary, nonstationary, and dynamic metabolic flux analysis (MFA) are numerous. This work presents MID Max, a novel LC–MS/MS workflow, acquisition, and isotopomer deconvolution method for MFA...... that takes advantage of additional scan types that maximizes the number of mass isotopomer distributions (MIDs) that can be acquired in a given experiment. The analytical method was found to measure the MIDs of 97 metabolites, corresponding to 74 unique metabolite-fragment pairs (32 precursor spectra and 42...

  15. Isotopomer analysis of production and consumption mechanisms of N2O and CH4 in an advanced wastewater treatment system.

    Science.gov (United States)

    Toyoda, Sakae; Suzuki, Yuuri; Hattori, Shohei; Yamada, Keita; Fujii, Ayako; Yoshida, Naohiro; Kouno, Rina; Murayama, Kouki; Shiomi, Hiroshi

    2011-02-01

    Wastewater treatment processes are believed to be anthropogenic sources of nitrous oxide (N(2)O) and methane (CH(4)). However, few studies have examined the mechanisms and controlling factors in production of these greenhouse gases in complex bacterial systems. To elucidate production and consumption mechanisms of N(2)O and CH(4) in microbial consortia during wastewater treatment and to characterize human waste sources, we measured their concentrations and isotopomer ratios (elemental isotope ratios and site-specific N isotope ratios in asymmetric molecules of NNO) in water and gas samples collected by an advanced treatment system in Tokyo. Although the estimated emissions of N(2)O and CH(4) from the system were found to be lower than those from the typical treatment systems reported before, water in biological reaction tanks was supersaturated with both gases. The concentration of N(2)O, produced mainly by nitrifier-denitrification as indicated by isotopomer ratios, was highest in the oxic tank (ca. 4000% saturation). The dissolved CH(4) concentration was highest in in-flow water (ca. 3000% saturation). It decreased gradually during treatment. Its carbon isotope ratio indicated that the decrease resulted from bacterial CH(4) oxidation and that microbial CH(4) production can occur in anaerobic and settling tanks.

  16. Uniform and selective deuteration in two-dimensional NMR of proteins

    International Nuclear Information System (INIS)

    LeMaster, D.M.

    1990-01-01

    This paper reports on the practicality of isotopic labeling, particularly deuteration, that has received considerable impetus from advances in molecular biology, which have allowed ready production of NMR quantities of labeled proteins. Protein expression in Escherichia coli allows use of the considerable metabolic genetics known for the organism in shaping the biosynthetic process to meet the labeling demands of the NMR experiments. In addition to deuteration's common use in spectral assignment problems, it also offers considerable potential for enhancing the quality of the nuclear Overhauser effect (NOE) distance and dihedral angle constraints used for solution structural analysis of proteins. Recent reviews emphasize the sample preparation and spectral benefits of protein deuteration

  17. Highly selective deuteration of pharmaceutically relevant nitrogen-containing heterocycles: a flow chemistry approach.

    Science.gov (United States)

    Ötvös, Sándor B; Mándity, István M; Fülöp, Ferenc

    2011-08-01

    A simple and efficient flow-based technique is reported for the catalytic deuteration of several model nitrogen-containing heterocyclic compounds which are important building blocks of pharmacologically active materials. A continuous flow reactor was used in combination with on-demand pressure-controlled electrolytic D(2) production. The D(2) source was D(2)O, the consumption of which was very low. The experimental set-up allows the fine-tuning of pressure, temperature, and flow rate so as to determine the optimal conditions for the deuteration reactions. The described procedure lacks most of the drawbacks of the conventional batch deuteration techniques, and additionally is highly selective and reproducible.

  18. [2H26]-1-epi-Cubenol, a completely deuterated natural product from Streptomyces griseus

    Directory of Open Access Journals (Sweden)

    Christian A. Citron

    2013-12-01

    Full Text Available During growth on fully deuterated medium the volatile terpene [2H26]-1-epi-cubenol was released by the actinomycete Streptomyces griseus. This compound represents the first completely deuterated terpene obtained by fermentation. Despite a few previous reports in the literature the operability of this approach to fully deuterated compounds is still surprising, because the strong kinetic isotope effect of deuterium is known to slow down all metabolic processes in living organisms. Potential applications of completely labelled compounds from natural sources in structure elucidation, biosynthetic or pharmacokinetic investigations are discussed.

  19. Magnetic properties of nickel halide hydrates including deuteration effects

    Energy Technology Data Exchange (ETDEWEB)

    DeFotis, G.C., E-mail: gxdefo@wm.edu [Chemistry Department, College of William & Mary, Williamsburg, VA, 23187 United States (United States); Van Dongen, M.J.; Hampton, A.S.; Komatsu, C.H.; Trowell, K.T.; Havas, K.C.; Davis, C.M.; DeSanto, C.L. [Chemistry Department, College of William & Mary, Williamsburg, VA, 23187 United States (United States); Hays, K.; Wagner, M.J. [Chemistry Department, George Washington University, Washington, DC, 20052 United States (United States)

    2017-01-01

    Magnetic measurements on variously hydrated nickel chlorides and bromides, including deuterated forms, are reported. Results include locations and sizes of susceptibility maxima, T{sub max} and χ{sub max}, ordering temperatures T{sub c}, Curie constants and Weiss theta in the paramagnetic regime, and primary and secondary exchange interactions from analysis of low temperature data. For the latter a 2D Heisenberg model augmented by interlayer exchange in a mean-field approximation is applied. Magnetization data to 16 kG as a function of temperature show curvature and hysteresis characteristics quite system dependent. For four materials high field magnetization data to 70 kG at 2.00 K are also obtained. Comparison is made with theoretical relations for spin-1 models. Trends are apparent, primarily that T{sub max} of each bromide hydrate is less than for the corresponding chloride, and that for a given halide nD{sub 2}O (n=1 or 2) deuterates exhibit lesser T{sub max} than do nH{sub 2}O hydrates. A monoclinic unit cell determined from powder X-ray diffraction data on NiBr{sub 2}·2D{sub 2}O is different from and slightly larger than that of NiBr{sub 2}·2H{sub 2}O. This provides some rationale for the difference in magnetic properties between these. - Highlights: • The magnetism of Ni(II) chloride and bromide dihydrates and monohydrates is studied. • Effects of replacing H{sub 2}O by D{sub 2}O are examined for both hydration states and both halides. • Exchange interactions in bromides are weaker than in corresponding chlorides. • Exchange interactions are weaker in D{sub 2}O than in corresponding H{sub 2}O containing systems. • The unit cell of NiBr{sub 2}·2D{sub 2}O is different from and slightly larger than that of NiBr{sub 2}·2H{sub 2}O.

  20. Effect of deuteration on the vibrational spectra of organic molecules

    International Nuclear Information System (INIS)

    Billes, Ferenc; Endredi, Henrietta; Varady, Balazs

    2001-01-01

    The stable isotope substitution of organic compounds deforms their vibrational spectra. The modifications of the spectra appear as band shifts and changes in intensities and shapes of the bands. The magnitude of the effect depends on the ratio of the masses of the new and old isotopes and on the atom active position. According to these mentioned reasons large effects can be observed only if hydrogen atoms are substituted. With the effect of the substitution we dealt already in a former lecture. In this lecture we concentrate on the effect of the change of hydrogen to deuterium. We investigate the changes both experimentally and theoretically. There are two possibilities: - the hydrogen atom is in an active position, its interaction with the environment is strong, either it can dissociate or move on the skeleton of the molecule (tautomerism, resonance) and it can build hydrogen bond, (e.g. it is connected to nitrogen and oxygen atoms); - the hydrogen atom is in an indifferent position in the molecule, its interaction with the environment is weak (e.g. it joins carbon atom). When building the hydrogen bond besides the hydrogen donors also acceptors exist, namely, oxygen and nitrogen atoms having non-bonded electron pairs. When comparing the experimental and theoretical (calculated) effects of this type of isotope changes one must take into account that the calculations refer to the isolated molecule while the experimental spectra characterize the compound. The hydrogen bond is a very strong intermolecular interaction and produces tremendous changes in the infrared spectrum of the molecule in comparison to the imagined theoretical spectrum of the molecule. Some bands disappear, appear, or shift and deform drastically. The H/D change diminishes these effects. Of course, these changes entail the shift of several bands. The Raman spectrum is less sensitive to the large dipole moment changes therefore the deuteration effect is there less dramatic. Deuteration of hydrogen

  1. Studies on /sup 13/C-NMR spectroscopy of carbohydrates. Application of selective deuteration

    Energy Technology Data Exchange (ETDEWEB)

    Mizutani, Kenji; Kajita, Hitomi; Tashima, Takako; Tanaka, Osamu (Hiroshima Univ. (Japan). School of Medicine)

    1982-10-01

    Recently, Stuart et al. have reported that on heating with deuterated Raney nickel in D/sub 2/O, hexopyranosides and oligosaccharides were deuterated selectively at carbon atoms bound to a free hydroxyl group. For the application of this procedure to chemistry and biochemistry of more complex carbohydrates, further study on this reaction was conducted. On prolonged treatment with Raney nickel (24h), methyl ..cap alpha..-L-arabinopyranoside (4) and ..beta..-D-xylopyranoside (5) were partially epimerized to give (5) and methyl ..cap alpha..-L-lyxopyranoside (6) from (4), and methyl ..beta..-D-ribopyranoside (7) and (4) from (5), respectively. Methyl ..cap alpha..-L-rhamnopyranoside (8) was epimerized more slowly to yield methyl 6-deoxy-..cap alpha..-L-glucopyranoside (9). The best conditions for the deuteration under minimizing the epimerization was refluxing with W-7 type deuterated Raney nickel in D/sub 2/O-dioxane (1 : 1) or methanol-d/sub 4/-D/sub 2/O (1 : 1) for about 9h. Methyl ..beta..-sophoroside (13), methyl ..beta..-cellobioside (23) and ..beta..-sophorosyl and ..beta..-gentiobiosyl units of ginsenoside-Rb/sub 1/ (24), a Ginseng-saponin, were deuterated as expected under these conditions, while C-2 and 4 of the inner ..beta..-glucopyranosyl moiety of methyl ..beta..-laminaribioside (18) and C-4 of the inner ..beta..-glucopyranosyl moiety of methyl 2,3-di-O-..beta..-D-glucopyranosyl-..beta..-D-glucopyranoside (22) remained almost undeuterated. Deuteration of ..cap alpha..-1,6-glucan (25) proceeded rather slowly than those of mono- and oligosaccharide to obtain the expected deuteration after treatment for 24h. In the case of the deuteration of cis- and dl-trans-1, 2-cyclohexanediols (11) and ( (12), both deuteration and epimerization proceeded very fast to give an equilibrated mixture of (11-d/sub 2/) and (12-d/sub 2/) within 9h, while the isolated carbinyl carbon (C-12) of (24) was not deuterated. Further, by means of the above selective deuteration, /sup 13

  2. Synthesis, purification and physico-chemical characterization of the deuterized chloroform

    International Nuclear Information System (INIS)

    Mihaila, Vasile; Chiper, Diana

    1999-01-01

    This work refers to deuterized chloroform synthesis and purification methods. Three preparation methods of deuterized chloroform are presented. In the first method the direct chlorination of methane (CH 4 + 3Cl 2 ) in the presence of light and in an oxygen-free atmosphere results in CHCl 3 + 3HCl. The method's drawback is that the resulting product is impure, being obtained also secondary chlorinated compounds, such as CHCl, CH 2 Cl 2 and CCl 4 . The second method consists in chlorination of acetaldehyde or acetone, in basic catalysis and in halogen excess (α substitution with direct synthesis of trihalogen compound), followed by a haloform reaction (hydrolytic splitting) in the presence of chlorinated lime. This method makes use of decarbolyzing of trichlor acetate acid (as a sodium salt), what results in CL 3 CH + NaHCO 3 . This method is the most suitable for the deuterized chloroform synthesis, since the reaction takes place in absence of other hydrogen atoms (protons) and in deuterized water of 99.87% purity, according to the following reaction: Cl 3 C-COONa → (D 2 O) → Cl 2 CD + NaDCO 3 . Another advantage is that this method avoids the synthesis of secondary products, which could entail additional purifications (distillations, rectification, a.s.o.). The deuterized chloroform is separated from the deuterized sodium bicarbonate aqueous solution by washing with deuterized water, in a liquid to liquid separating funnel. After separation, deuterized chloroform is dried in nitrogen atmosphere. The characterization of the final product is carried out by nuclear magnetic resonance spectrometry. (authors)

  3. Synthesis, purification and physico-chemical characterization of the deuterized chloroform

    International Nuclear Information System (INIS)

    Mihaila, V.; Olteanu-Chiper, D.

    1999-01-01

    This work refers to deuterized chloroform synthesis and purification methods. Three methods for obtaining deuterized chloroform are presented. 1. The direct chlorination of methane, in presence of light and in oxygen-free atmosphere: CH 4 + 3 Cl 2 + ℎν→ CHCl 3 + 3 HCl. The method's drawback is that the product obtained is impure, as other chlorinated compounds such as CH 3 Cl, CH 2 Cl 2 , CCl 4 also result. 2. Chlorination of acetaldehyde or acetone, in basic catalysis and in halogen excess (α substitution with direct synthesis of trihalogen compound), followed by a haloform reaction (hydrolytic splitting) in presence of chlorinated lime: CH 3 CHO (Cl 2 /HO - )/(-HCl)Cl 3 C-CHO (CaCl 2 /HOH)/(-(HCOO) 2 Ca) CHCl 3 and CH 3 -CO-CH 3 (Cl 2 /HO)/(-HCl) Cl 3 C-CO-CH 3 (NaOH)/(-CH 3 COONa) CHCl 3 . 3. Decarboxylizing of trichloroacetate acid (as sodium salt): Cl 3 C-COONa (t deg C)/(H 2 O) Cl 3 CH + NaHCO 3 . This method is the most suitable for the deuterized chloroform synthesis since the reaction takes place in absence of other hydrogen atoms (protons) and in deuterized water 99,87% purity, according to the following reaction: Cl 3 C-COONa (t deg C)/(D 2 O) Cl 3 CD + NaDCO 3 . Another advantage is that this method avoids the synthesis of secondary products which could entail additional purifications (distillations, rectifications, a.s.o.). The deuterized chloroform is separated from the deuterized sodium bicarbonate aqueous solution by washing with deuterized water, in a liquid-to-liquid separating funnel. After separation, the deuterized chloroform is dried in nitrogen atmosphere. The characterization of the final product is carried out through Nuclear Magnetic Resonance Spectrometry. (authors)

  4. Solid deuterated water in space: detection constraints from laboratory experiments

    Science.gov (United States)

    Urso, R. G.; Palumbo, M. E.; Baratta, G. A.; Scirè, C.; Strazzulla, G.

    2018-06-01

    The comparison between astronomical spectra and laboratory experiments is fundamental to spread light on the structure and composition of ices found in interstellar dense molecular clouds and in Solar System bodies. Water is among the most abundant solid-phase species observed in these environments, and several attempts have been made to investigate the presence of its solid-phase isotopologues. In particular, the detection of the O-D stretching mode band at 4.1 μm due to both D2O and HDO within icy grain mantles is still under debate, and no detection have been reported about the presence of these species within icy bodies in the Solar System yet. In the near future, an important contribution could derive from the data acquired in the O-D stretching mode spectral range by the sensitive instruments on board the James Webb Space Telescope. With this in mind, we performed several laboratory experiments to study the O-D stretching mode band in solid mixtures containing water and deuterated water deposited in the temperature range between 17 and 155 K, in order to simulate astrophysical relevant conditions. Furthermore, samples have been studied at various temperature and irradiated with energetic ions (200 keV H+) in order to study the effects induced by both thermal and energetic processing. Our results provide some constraints on the detection of the 4.1 μm band in astronomical environments.

  5. Dispersion Relation for Skeletal Vibrations in Deuterated Polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Feldkamp, L. A.; Venkataraman, G.; King, J. S. [Department of Nuclear Engineering, University of Michigan, Ann Arbor, MI (United States)

    1968-09-15

    The low frequency vibrations in polyethylene have been studied previously, utilizing the incoherent scattering technique which yields an amplitude-weighted density of states. In the present work the dispersion relations have been obtained directly by observing the coherent scattering from a deuterated sample. This represents the first such measurement on a crystalline polymer. A target in which the molecular chain axes were approximately parallel was prepared by stretching polycrystalline material. The FWHM of the rocking curve for the (002) reflection was measured to be 9 Degree-Sign . Constant-Q and constant-E scans were made on the University of Michigan triple-axis spectrometer at room temperature to observe phonons propagating along the chain direction. The resulting dispersion curve for the v{sub 5} mode follows generally the calculated curve of Tasumi and Krimm with systematically lower frequencies. The maximum frequency of 1.36 x 10{sup 13} Hz agrees with the cut-off frequency determined previously from the incoherent scattering spectrum. (author)

  6. Deuterated-xylene (xylene-d{sub 10}; EJ301D): A new, improved deuterated liquid scintillator for neutron energy measurements without time-of-flight

    Energy Technology Data Exchange (ETDEWEB)

    Becchetti, F.D.; Raymond, R.S.; Torres-Isea, R.O. [Department of Physics, University of Michigan, Ann Arbor, MI 48109 (United States); Di Fulvio, A.; Clarke, S.D.; Pozzi, S.A. [Department of Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109 (United States); Febbraro, M. [Oak Ridge National Laboratory, Oak Ridge, TN 37830 (United States)

    2016-06-01

    In conjunction with Eljen Technology, Inc. (Sweetwater,TX) we have designed, constructed, and evaluated a 3 in. ×3 in. deuterated-xylene organic liquid scintillator (C{sub 8}D{sub 10}; EJ301D) as a fast neutron detector. Similar to deuterated benzene (C{sub 6}D{sub 6}; NE230, BC537, and EJ315) this scintillator can provide good pulse-shape discrimination between neutrons and gamma rays, has good timing characteristics, and can provide a light spectrum with peaks corresponding to discrete neutron energy groups up to ca. 20 MeV. Unlike benzene-based detectors, deuterated xylene is less volatile, less toxic, is not known to be carcinogenic, has a higher flashpoint, and hence is much safer for many applications. In addition EJ301D can provide slightly more light output and better PSD than deuterated-benzene scintillators. We show that, as with deuterated-benzene scintillators, the light-response spectra can be unfolded to provide useable neutron energy spectra without need for time-of-flight (ToF). An array of these detectors arranged at many angles close to a reaction target can be much more effective (×10 to ×100 or more) than an array of long-path ToF detectors which must utilize a narrowly-bunched and pulse-selected beam. As we demonstrate using a small Van de Graaff accelerator, measurements can thus be performed when a bunched and pulse-selected beam (as needed for time-of-flight) is not available.

  7. THE L1157-B1 ASTROCHEMICAL LABORATORY: MEASURING THE TRUE FORMALDEHYDE DEUTERATION ON GRAIN MANTLES

    International Nuclear Information System (INIS)

    Fontani, F.; Codella, C.; Ceccarelli, C.; Lefloch, B.; Viti, S.; Benedettini, M.

    2014-01-01

    L1157 is a prototypical chemically active outflow driven by a low-mass class-0 protostar, and B1 is its brightest bow shock. Toward L1157-B1, several emission lines of deuterated molecules have been detected for the first time by Codella et al. The authors suggested that these were formed on grain mantles, and then released into the gas phase by the passage of the shock. In this Letter we report observations obtained at high angular resolution with the Plateau de Bure Interferometer of HDCO and CH 2 DOH. The emission of HDCO perfectly delineates the region of the interface between the fast jet and the slower ambient material, confirming the predictions of the previous work that deuterated species were formed on grain mantles and then released into the gas phase by the passage of the shock. CH 2 DOH emission is fainter and thus its emitting region is not well determined. The deuterated fraction HDCO/H 2 CO is ∼0.1 in the HDCO emitting region, an order of magnitude larger than the upper limit found in the surrounding material, probably dominated by warm-gas chemistry and less affected by grain evaporation. Our study represents the first clear evidence ever found of a deuterated molecule as shock tracer, and yields an indirect but ''clean'' measurement of the deuteration of the ices covering the dust grains during the cold pre-protostellar phase

  8. Helium (24He, 23He) within deuterated Pd-black

    International Nuclear Information System (INIS)

    Arata, Yoshiaki; Zhang, Yue-Chang

    1997-01-01

    Authors have clearly proven for the first time that deuterium nuclear reaction was continuously generated inside a highly deuterated solid by showing both of the excess energy and corresponding amount of helium as the reaction product generated simultaneously. Whenever there is a nuclear fusion reaction inside a metal, helium generated is unable to escape to the surroundings and is trapped in a frozen state inside that metal. The concentration of the helium within the metal will rise with increasing rate of reactions. Pd-black is under such state as the sample used and sealed within the 'closed QMS' developed by the authors (closed vessel including the Getter pump and the QMS). It is completely separated from the surroundings and the internal gases are removed to create super-vacuum. The reaction product released by the 'Sample-Heating' process (room temp. ↔ 1500(degC)) is thus the only matter which occupies the interior of the closed vessel and its detection by the QMS is assured. When the 'closed QMS' works under the above mentioned-state, it was clarified that the 'ash' or the reaction product of this fusion reaction within a solid is 2 4 He and 2 3 He and their ratio is 2 4 He/ 2 3 He ≅ 4. It can be concluded from the result that the main reaction product is 2 4 He and it is created directly as an inherent feature of the solid-state nuclear fusion. Authors think that the reaction process responsible for the creation of 2 3 He may be a different one from that created 2 4 He. One of which is the Rutherford reaction process and the other occurs based on the specific properties of solid, similar to the case of 2 4 He. The existence of 1 3 T will be required that the process is responsible for the generation of 2 3 He as the Rutherford reaction. The proof for the existence of 1 3 T within the 'closed QMS', however, was not obtained in this experiments. (author)

  9. Insight into nitrous oxide production processes in the western North Pacific based on a marine ecosystem isotopomer model

    Science.gov (United States)

    Yoshikawa, C.; Sasai, Y.; Wakita, M.; Honda, M. C.; Fujiki, T.; Harada, N.; Makabe, A.; Matsushima, S.; Toyoda, S.; Yoshida, N.; Ogawa, N. O.; Suga, H.; Ohkouchi, N.

    2016-02-01

    Based on the observed inverse relationship between the dissolved oxygen and N2O concentrations in the ocean, previous models have indirectly predicted marine N2O emissions from the apparent oxygen utilization (AOU), In this study, a marine ecosystem model that incorporates nitrous oxide (N2O) production processes (i.e., ammonium oxidation during nitrification and nitrite reduction during nitrifier denitrification) was newly developed to estimate the sea-air N2O flux and to quantify N2O production processes. Site preference of 15N (SP) in N2O isotopomers (14N15N16O and 15N14N16O) and the average nitrogen isotope ratio (δ15N) were added to the model because they are useful tracers to distinguish between ammonium oxidation and nitrite reduction. This model was applied to two contrasting time series sites, a subarctic station (K2) and a subtropical station (S1) in the western North Pacific. The model was validated with observed nitrogen concentration and nitrogen isotopomer datasets, and successfully simulated the higher N2O concentrations, higher δ15N values, and higher site preference values for N2O at K2 compared with S1. The annual mean N2O emissions were estimated to be 34 mg N m-2 yr-1 at K2 and 2 mg N m-2 yr-1 at S1. Using this model, we conducted three case studies: 1) estimating the ratio of in-situ biological N2O production to nitrate (NO3-) production during nitrification, 2) estimating the ratio of N2O production by ammonium oxidation to that by nitrite reduction, and 3) estimating the ratio of AOA ammonium oxidation to AOB ammonium oxidation. The results of case studies estimated the ratios of in situ biological N2O production to nitrate production during nitrification to be 0.22% at K2 and 0.06% at S1. It is also suggested that N2O was mainly produced via ammonium oxidation at K2 but was produced via both ammonium oxidation and nitrite reduction at S1. It is also revealed that 80% of the ammonium oxidation at K2 was caused by archaea in the subsurface

  10. Low-temperature structural phase transition in deuterated and protonated lithium acetate dihydrate

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, F., E-mail: schroeder@kristall.uni-frankfurt.d [Goethe-Universitaet Frankfurt am Main, Institut fuer Geowissenschaften, Abt. Kristallographie, Altenhoeferallee 1, 60438 Frankfurt am Main (Germany); Winkler, B.; Haussuehl, E. [Goethe-Universitaet Frankfurt am Main, Institut fuer Geowissenschaften, Abt. Kristallographie, Altenhoeferallee 1, 60438 Frankfurt am Main (Germany); Cong, P.T.; Wolf, B. [Goethe-Universitaet Frankfurt am Main, Physikalisches Institut, Max-von-Laue-Strasse 1, 60438 Frankfurt am Main (Germany); Avalos-Borja, M. [Instituto Potosino de Investigacion Cientifica y Tecnologica, A.C. Camino a la Presa San Jose 2055, Col. Lomas 4 seccion CP 78216, San Luis Potosi (Mexico); Quilichini, M.; Hennion, B. [Laboratoire Leon Brillouin, CEN Saclay, 91191 Gif-sur-Yvette (France)

    2010-08-15

    Heat capacity measurements of protonated lithium acetate dihydrate show a structural phase transition at T = 12 K. This finding is in contrast to earlier work, where it was thought that only the deuterated compound undergoes a low temperature structural phase transition. This finding is confirmed by low temperature ultrasound spectroscopy, where the structural phase transition is associated with a velocity decrease of the ultrasonic waves, i.e. with an elastic softening. We compare the thermodynamic properties of the protonated and deuterated compounds and discuss two alternatives for the mechanism of the phase transition based on the thermal expansion measurements.

  11. Quantitation of deuterated and non-deuterated phenylalanine and tyrosine in human plasma using the selective ion monitoring method with combined gas chromatography-mass spectrometry

    International Nuclear Information System (INIS)

    Zagalak, M.-J.; Curtius, H.-Ch.; Leimbacher, W.; Redweik, U.

    1977-01-01

    A specific method is described for the quantitative analysis of deutarated and non-deuterated phenylalanine and tyrosine in human plasma by gas chromatography-mass spectrometry using selective ion monitoring. From the several derivatives investigated, the N- or N,O-trifluoroacetyl methyl esters were found to be the most suitable for our purposes. DL-Phenylalanine-4-d 1 and L-tyrosine-d 7 were used as internal standards. The sensitivity of this method permits the measurement of amounts as small as ca. 2.5 ng/ml in plasma for both phenylalanine and tyrosine. The coefficients of variation were found to be ca. 1.6% (n=12) for phenylalanine and 3.0% (n=12) for tyrosine. Using this method, an in vivo determination of phenylalanine-4-monooxygenase activity in humans is possible by loading the subjects with deuterated L-phenylalanine-d 5 (accepted as substrate by phenylalanine-4-monooxygenase E.C. 1.14.16.1) and the subsequent measuring of deuterated L-tyrosine-d 4 formed and residual L-phenylalanine-d 5

  12. Formation of H_2^+ and its Isotopomers by Radiative Association: the Role of Shape and Feshbach Resonances

    Science.gov (United States)

    Beyer, Maximilian; Merkt, Frederic

    2017-06-01

    The recent observations [1,2] of shape and Feshbach resonances in the high-resolution photoelectron spectra of H_2, HD and D_2 in the vicinity of the dissociation thresholds of H_2^+, HD^+ and D_2^+ raise questions concerning their potential role in the formation of H_2^+ and its isotopomers in the early universe by radiative association, a topic of astrophysical interest [3]. Close-coupling calculations for the cross sections of the reactions {H}^+ + {H} &\\to {H}_2^+ + hν {H}^+ + {D} &\\to {HD}^+ + hν {D}^+ + {H} &\\to {HD}^+ + hν {D}^+ + {D} &\\to {D}_2^+ + hν, will be presented which take into account nonadiabatic couplings involving rovibronic and hyperfine interactions, as well as relativistic and radiative corrections. The calculated energies and widths will be compared with the experimental results of Ref. [1,2] for H_2^+ and new data for HD^+ and D_2^+. The effect of the resonances on the radiative association rate coefficients will be discussed, also in comparison with earlier studies [4]. [1] M. Beyer and F. Merkt, Phys. Rev. Lett. 116, 093001 (2016). [2] M. Beyer and F. Merkt, J. Mol. Spectrosc. 330, 147 (2016). [3] Molecule formation in dust-poor environments, J. F. Babb and K. P. Kirby, in "The molecular astrophysics of stars and galaxies", T. W. Hartquist and D. A. Williams, eds., Oxford University Press, Oxford, 1998, pp. 11-34. [4] D. E. Ramaker and J. M. Peek, Phys. Rev. A 13, 58 (1976).

  13. Preparation of α-deuterated L-amino acids using E.coli cells containing tryptophanase

    International Nuclear Information System (INIS)

    Faleev, N.G.; Ruvinov, S.B.; Saporovskaya, M.B.; Belikov, V.M.; Zakomyrdina, L.N.; Sakharova, I.S.; Torchinskij, Yu.M.

    1989-01-01

    Method for preparation of a series of α-deuterated L-amino acids of high optical purity with quantitative chemica yield, suing stereospecific isotopic exchange in D 2 O under the effect of E.coli cells with high tryptophanase activity was developed

  14. A Neutron Scattering Study of Phonons in Per-Deuterated S-Triazine

    DEFF Research Database (Denmark)

    Doue, M. T.; Heilmann, I. U.; Kjems, Jørgen

    1983-01-01

    The lattice dynamics of a fully-deuterated single crystal of s-triazine is investigated using the technique of coherent inelastic neutron scattering. Detailed measurements of the temperature dependence of the dispersion of the soft acoustic mode associated with the ferroelastic phase transition...

  15. Habit control of deuterated potassium dihydrogen phosphate crystal for laser applications

    Science.gov (United States)

    Guzman, L. A.; Suzuki, M.; Fujimoto, Y.; Fujioka, K.

    2016-03-01

    In this study we investigate the habit of partially deuterated potassium dihydrogen phosphate (DKDP) crystals in the presence of Al3+ ions. We have grown single DKDP crystals in (50wt% and 80wt%) partially deuterated solutions and in solutions doped with Al3+ ions (2 ppm) by the point-seed rapid growth technique at controlled supercooling (ΔT=10°C). The growth length of each crystal face was measured and the aspect ratio was calculated. We found that crystals grown in partially deuterated solutions are similar in aspect ratio, while, crystals grown in deuterated solutions doped with Al3+ ions showed a relative change in aspect ratio, the crystal increased in size in the pyramidal direction (vertical axis direction). Crystal characteristics were also analyzed by X-ray diffraction, FTIR and Raman spectroscopy. We have speculated that the relative habit modification is due to a probably adsorption and inclusions of Al3+ ions in the prismatic section of the crystal.

  16. Habit control of deuterated potassium dihydrogen phosphate crystal for laser applications

    International Nuclear Information System (INIS)

    Guzman, L A; Suzuki, M; Fujimoto, Y; Fujioka, K

    2016-01-01

    In this study we investigate the habit of partially deuterated potassium dihydrogen phosphate (DKDP) crystals in the presence of Al 3+ ions. We have grown single DKDP crystals in (50wt% and 80wt%) partially deuterated solutions and in solutions doped with Al 3+ ions (2 ppm) by the point-seed rapid growth technique at controlled supercooling (ΔT=10°C). The growth length of each crystal face was measured and the aspect ratio was calculated. We found that crystals grown in partially deuterated solutions are similar in aspect ratio, while, crystals grown in deuterated solutions doped with Al 3+ ions showed a relative change in aspect ratio, the crystal increased in size in the pyramidal direction (vertical axis direction). Crystal characteristics were also analyzed by X-ray diffraction, FTIR and Raman spectroscopy. We have speculated that the relative habit modification is due to a probably adsorption and inclusions of Al 3+ ions in the prismatic section of the crystal. (paper)

  17. Use of deuterated tyrosine and phenylalanine in the study of catecholamine and aromatic acid metabolism

    International Nuclear Information System (INIS)

    Curtius, H.C.; Redweik, U.; Steinmann, B.; Leimbacher, W.; Wegmann, H.

    1975-01-01

    Deuterated tyrosine and phenylalanine have been used for the study of their respective metabolism in patients with phenylketonuria (PKU) and in healthy persons. Urinary excretion of dopamine and its metabolites was studied by GC-MS after oral administration of deuterated L-tyrosine in 2 patients with PKU and in normal controls at low and high plasma phenylalanine levels. From these studies it seemed that the in vivo tyrosine 3-hydroxylase activity and thus the formation of L-dopa depend on the phenylalanine concentration in plasma and also in tissues. After loading 3 mentally retarded patients with 3,5-[ 2 H 2 ]-4-hydroxyphenylalanine, we found, among others, excretion of deuterated m-hydroxyphenyl-hydracrylic acid, p-hydroxymandelic acid, p-hydroxybenzoic acid, p-hydroxyhippuric acid, benzoic acid and hippuric acid. An intramolecular rearrangement is postulated. Deuterated phenylalanine was used to investigate phenylalanine and dopa metabolism in PKU. In addition, one untreated person with PKU of normal intelligence and normal excretion of catecholamines at high plasma phenylalanine concentration was investigated in order to see whether there exists an alternative metabolic pathway from phenylalanine to dopa formation

  18. Biosynthetic preparation of selectively deuterated phosphatidylcholine in genetically modified Escherichia coli

    DEFF Research Database (Denmark)

    Maric, Selma; Thygesen, Mikkel Boas; Schiller, Jürgen

    2015-01-01

    Phosphatidylcholine (PC) is a major component of eukaryotic cell membranes and one of the most commonly used phospholipids for reconstitution of membrane proteins into carrier systems such as lipid vesicles, micelles and nanodiscs. Selectively deuterated versions of this lipid have many applicati...

  19. Experimental Observations of Nuclear Activity in Deuterated Materials Subjected to a Low-Energy Photon Beam

    Science.gov (United States)

    Steinetz, Bruce M.; Benyo, Theresa L.; Pines, Vladimir; Pines, Marianna; Forsley, Lawrence P.; Westmeyer, Paul A.; Chait, Arnon; Becks, Michael D.; Martin, Richard E.; Hendricks, Robert C.; hide

    2017-01-01

    Exposure of highly deuterated materials to a low-energy (nom. 2 MeV) photon beam resulted in nuclear activity of both the parent metals of hafnium and erbium and a witness material (molybdenum) mixed with the reactants. Gamma spectral analysis of all deuterated materials, ErD2.8+C36D74+Mo and HfD2+C36D74+Mo, showed that nuclear processes had occurred as shown by unique gamma signatures. For the deuterated erbium specimens, posttest gamma spectra showed evidence of radioisotopes of erbium ((163)Er and (171)Er) and of molybdenum ((99)Mo and (101)Mo) and by beta decay, technetium (99mTc and 101Tc). For the deuterated hafnium specimens, posttest gamma spectra showed evidence of radioisotopes of hafnium (180mHf and 181Hf) and molybdenum ((99)Mo and (101)Mo), and by beta decay, technetium ((99m)Tc and (101)Tc). In contrast, when either the hydrogenated or non-gas-loaded erbium or hafnium materials were exposed to the gamma flux, the gamma spectra revealed no new isotopes. Neutron activation materials showed evidence of thermal and epithermal neutrons. CR-39 solid-state nuclear track detectors showed evidence of fast neutrons with energies between 1.4 and 2.5 MeV and several instances of triple tracks, indicating (is) greater than 10 MeV neutrons. Further study is required to determine the mechanism causing the nuclear activity.

  20. Development of a new neutron mirror made of deuterated Diamond-like carbon

    International Nuclear Information System (INIS)

    Sakurai, Dai; Chiba, Junsei; Shimizu, Hirohiko M; Nishimura, Daiki; Ino, Takashi; Kaneko, Naokatsu; Muto, Suguru; Kakusho, Nobunori; Seki, Yoshichika; Katayama, Ryo; Kitaguchi, Masaaki; Mishima, Kenji; Yamashita, Satoru; Ozeki, Kazuhide; Yoshioka, Tamaki

    2014-01-01

    We developed a new neutron mirror made of Diamond-like carbon (DLC). DLC is a film of amorphous carbon that has characteristics of both diamond and graphite. We produced DLC mirrors by ionization deposition method which is one of the chemical vapor deposition (CVD). Generally, DLC made by CVD contents a few tens of percentages of hydrogen. It decreases the Fermi potential of the DLC coating because hydrogen has negative Fermi potential. In order to increase the Fermi potential of the coating, we deuterated the DLC by using deuterated benzene for the source gas. The characteristics of the deuterated DLC(DDLC) coating was evaluated by RBS, ERDA, x-ray reflectivity, AFM. As a result, DDLC coating has 243 neV due to deuteration, which is the same level as Ni. The RMS of height of the DDLC was 0.6nm so that the DDLC coating can be applied for a focusing mirror or specular transportation of pulsed neutron. Besides, we also develop Hydrogen/Deuterium DLC multiple layer mirror. So far, 4 layers mirror has been succeeded.

  1. Synthesis of multiple deuterated N-n-propyl-norapomorphine N-(d/sub 7/) and derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Yigong; Trainor, T.M.; Vouros, Paul; Neumeyer, J.L.

    1988-03-01

    Novapomorphine has been labelled using n-propyl iodide through alkylation of norcodeine followed by a multistep route which also affords the related deuterated analogs N-n-propylnorapocodeine, the prodrug 10,11-methylenedioxy-NPA and 10,11-dimethoxy-NPA.

  2. Exploring molecular complexity with ALMA (EMoCA): Deuterated complex organic molecules in Sagittarius B2(N2)

    Science.gov (United States)

    Belloche, A.; Müller, H. S. P.; Garrod, R. T.; Menten, K. M.

    2016-03-01

    Context. Deuteration is a powerful tracer of the history of the cold prestellar phase in star-forming regions. Apart from methanol, little is known about deuterium fractionation of complex organic molecules in the interstellar medium, especially in regions forming high-mass stars. Aims: Our goal is to detect deuterated complex organic molecules toward the high mass star-forming region Sagittarius B2 (Sgr B2) and derive the level of deuteration for these molecules. Methods: We use a complete 3-mm spectral line survey performed with the Atacama Large Millimeter/submillimeter Array (ALMA) to search for deuterated complex organic molecules toward the hot molecular core Sgr B2(N2). We constructed population diagrams and integrated intensity maps to fit rotational temperatures and emission sizes for each molecule. Column densities are derived by modeling the full spectrum under the assumption of local thermodynamic equilibrium. We compare the results to predictions of two astrochemical models that treat the deuteration process. Results: We report the detection of CH2DCN toward Sgr B2(N2) with a deuteration level of 0.4%, and tentative detections of CH2DOH, CH2DCH2CN, the chiral molecule CH3CHDCN, and DC3N with levels in the range 0.05%-0.12%. A stringent deuteration upper limit is obtained for CH3OD (cyanide, the four deuterated species of ethanol, and CH2DOCHO. Ethyl cyanide is less deuterated than methyl cyanide by at least a factor five. The [CH2DOH]/[CH3OD] abundance ratio is higher than 1.8. It may still be consistent with the value obtained in Orion KL. Except for methyl cyanide, the measured deuteration levels lie at least a factor four below the predictions of current astrochemical models. The deuteration levels in Sgr B2(N2) are also lower than in Orion KL by a factor of a few up to a factor ten. Conclusions: The discrepancy between the deuteration levels of Sgr B2(N2) and the predictions of chemical models, and the difference between Sgr B2(N2) and Orion KL may

  3. Molecular differences between deuterated and protonated polystyrenes using reversed-phase high-performance liquid chromatography.

    Science.gov (United States)

    Kayillo, Sindy; Gray, Michael J; Shalliker, R Andrew; Dennis, Gary R

    2005-05-06

    Isotopic substitution is a technique used to highlight particular bonds within a molecule for kinetic, spectroscopic and structure analysis. It is presumed that although some properties such as stretching frequencies will not be the same for substituted analogues, the chemical interactions will not vary appreciably as a function of labelling. Reversed-phase liquid chromatography has been used to demonstrate that there are significant differences between the chromatographic behaviour of a sequence of deuterated and protonated oligomeric polystyrenes. Two-dimensional reversed-phase liquid chromatography was used to show that even the diasteromers of the oligomers (n = 5) have retention mechanisms that are dependent on the subtle changes to the molecular conformation and electronic structure, which are a consequence of deuteration.

  4. TEM and EELS study of deuterated carbon: application to the fuel retention in tokamaks

    International Nuclear Information System (INIS)

    Bernier, N.

    2007-12-01

    We developed a methodology, based on the combination of TEM and EELS techniques, for a structural and chemical characterization, at a high spatial resolution, of a wide range of carbon materials. We i) optimized, in the framework of theoretical models, the sp2 fraction quantification from pure carbons by EELS ii) transferred this quantification to deuterated amorphous carbon layers iii) showed, from graphitized carbons, how the TEM-EELS combination allows to detect low concentrations of implanted D. Due to the accomplishment of these developments, we applied our approach to the study of D retention in composites C/C, which are the plasma-facing materials in TS. We showed that specific localized retention sites correspond to relatively large (∼ 3 mm.) cracks between fibres and matrix; such cracks offer a simple and direct path for deuterated amorphous carbon. The particle balance performed in TS is discussed in the light of this trapping mechanism. (author)

  5. Electron spin resonance and its implication on the maximum nuclear polarization of deuterated solid target materials

    International Nuclear Information System (INIS)

    Heckmann, J.; Meyer, W.; Radtke, E.; Reicherz, G.; Goertz, S.

    2006-01-01

    ESR spectroscopy is an important tool in polarized solid target material research, since it allows us to study the paramagnetic centers, which are used for the dynamic nuclear polarization (DNP). The polarization behavior of the different target materials is strongly affected by the properties of these centers, which are added to the diamagnetic materials by chemical doping or irradiation. In particular, the ESR linewidth of the paramagnetic centers is a very important parameter, especially concerning the deuterated target materials. In this paper, the results of the first precise ESR measurements of the deuterated target materials at a DNP-relevant magnetic field of 2.5 T are presented. Moreover, these results allowed us to experimentally study the correlation between ESR linewidth and maximum deuteron polarization, as given by the spin-temperature theory

  6. Solid polystyrene and deuterated polystyrene light output response to fast neutrons

    International Nuclear Information System (INIS)

    Simpson, R.; Danly, C.; Merrill, F. E.; Volegov, P. L.; Wilde, C.; Glebov, V. Yu.; Hurlbut, C.

    2016-01-01

    The Neutron Imaging System has proven to be an important diagnostic in studying DT implosion characteristics at the National Ignition Facility. The current system depends on a polystyrene scintillating fiber array, which detects fusion neutrons born in the DT hotspot as well as neutrons that have scattered to lower energies in the surrounding cold fuel. Increasing neutron yields at NIF, as well as a desire to resolve three-dimensional information about the fuel assembly, have provided the impetus to build and install two additional next-generation neutron imaging systems. We are currently investigating a novel neutron imaging system that will utilize a deuterated polystyrene (CD) fiber array instead of standard hydrogen-based polystyrene (CH). Studies of deuterated xylene or deuterated benzene liquid scintillator show an improvement in imaging resolution by a factor of two [L. Disdier et al., Rev. Sci. Instrum. 75, 2134 (2004)], but also a reduction in light output [V. Bildstein et al., Nucl. Instrum. Methods Phys. Res., Sect. A 729, 188 (2013); M. I. Ojaruega, Ph.D. thesis, University of Michigan, 2009; M. T. Febbraro, Ph.D. thesis, University of Michigan, 2014] as compared to standard plastic. Tests of the relative light output of deuterated polystyrene and standard polystyrene were completed using 14 MeV fusion neutrons generated through implosions of deuterium-tritium filled capsules at the OMEGA laser facility. In addition, we collected data of the relative response of these two scintillators to a wide energy range of neutrons (1-800 MeV) at the Weapons Neutrons Research Facility. Results of these measurements are presented.

  7. Solid polystyrene and deuterated polystyrene light output response to fast neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, R., E-mail: raspberry@lanl.gov; Danly, C.; Merrill, F. E.; Volegov, P. L.; Wilde, C. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Glebov, V. Yu. [Laboratory for Laser Energetics, Rochester, New York 14623 (United States); Hurlbut, C. [Eljen Technology, Sweetwater, Texas 79556 (United States)

    2016-04-15

    The Neutron Imaging System has proven to be an important diagnostic in studying DT implosion characteristics at the National Ignition Facility. The current system depends on a polystyrene scintillating fiber array, which detects fusion neutrons born in the DT hotspot as well as neutrons that have scattered to lower energies in the surrounding cold fuel. Increasing neutron yields at NIF, as well as a desire to resolve three-dimensional information about the fuel assembly, have provided the impetus to build and install two additional next-generation neutron imaging systems. We are currently investigating a novel neutron imaging system that will utilize a deuterated polystyrene (CD) fiber array instead of standard hydrogen-based polystyrene (CH). Studies of deuterated xylene or deuterated benzene liquid scintillator show an improvement in imaging resolution by a factor of two [L. Disdier et al., Rev. Sci. Instrum. 75, 2134 (2004)], but also a reduction in light output [V. Bildstein et al., Nucl. Instrum. Methods Phys. Res., Sect. A 729, 188 (2013); M. I. Ojaruega, Ph.D. thesis, University of Michigan, 2009; M. T. Febbraro, Ph.D. thesis, University of Michigan, 2014] as compared to standard plastic. Tests of the relative light output of deuterated polystyrene and standard polystyrene were completed using 14 MeV fusion neutrons generated through implosions of deuterium-tritium filled capsules at the OMEGA laser facility. In addition, we collected data of the relative response of these two scintillators to a wide energy range of neutrons (1-800 MeV) at the Weapons Neutrons Research Facility. Results of these measurements are presented.

  8. Upper Bound for Neutron Emission from Sonoluminescing Bubbles in Deuterated Acetone

    International Nuclear Information System (INIS)

    Camara, C. G.; Putterman, S. J.; Hopkins, S. D.; Suslick, K. S.

    2007-01-01

    An experimental search for nuclear fusion inside imploding bubbles of degassed deuterated acetone at 0 degree sign C driven by a 15 atm sound field and seeded with a neutron generator reveals an upper bound that is a factor of 10 000 less than the signal reported by Taleyarkhan et al. The strength of our upper bound is limited by the weakness of sonoluminescence, which we ascribe to the relatively high vapor pressure of acetone

  9. Some Routes in Forming C3Hn+ Ions and Deuterated Variants under Interstellar Conditions

    International Nuclear Information System (INIS)

    Savic, Igor; Gerlich, Dieter

    2006-01-01

    Laboratory experiments on hydrogenation and deuteration of C 3 + , C3H+ and C 3 H 2 + in collisions with H2 and HD have been performed from room temperature down to 15 K using a 22-pole ion-trap. At room temperature C 3 + reacts slowly with H2 but the reactivity increases with decreasing temperature. It has been shown that the association reaction C 3 + + H 2 → C 3 H 2 + + hν can compete with the exothermic reaction C 3 + + H 2 → C 3 H + + H. In collisions of C 3 + with HD, formation of C3D+ is slightly favored over C3H+ formation. A pronounced competition between various channels has been detected for deuterated variants of the C3H+ + H2 system. Most surprising is that formation of C3HD+ is over one hundred times faster then formation of C 3 H 2 + in collisions of C3H+ and HD. An tentative explanation is that the H-HD exchange takes place via an open-chain H2CCCH+ intermediate. Reactions of C 3 H 2 + and C 3 H 3 + with H2 are very slow. The formation of C3H2D+ or C 3 HD 2 + and finally C3HD via dissociative recombination has been discussed. The reaction C 3 H 3 + + HD → C 3 H 2 D + + H 2 can be ignored in astrochemical models since the reaction rate at 15 K is very small; however, quite efficient routes have been found starting from C 3 + and proceeding via deuterated C3H+ to C 3 H 2 + and C 3 H 3 + . The new reaction rate coefficients are recommended to be included in astrophysical databases. Nonetheless it is still unclear how to explain the large abundance of C3H2 and larger hydrocarbons and their deuterated variants observed in cold interstellar clouds

  10. A Deuteration Survey of Starless Clumps in GemOB1 and the First Quadrant

    Science.gov (United States)

    Henrici, Andrew; Shirley, Yancy L.; Svoboda, Brian

    2018-01-01

    One very strong chemical process in star-forming regions is the fractionation of deuterium in molecules, which results in an increase in the deuterium ratio many orders of magnitude over the ISM [D]/[H] ratio and provides a chemical probe of cold, dense regions. Recent maps of dust continuum emission at (sub)millimeter wavelengths have identified tens of thousands of dense clumps of gas and dust. By comparing these regions to infrared and radio surveys, we have identified starless clump candidates which have no evidence for embedded star formation. These objects represent the earliest phase of star formation throughout the Milky Way. One benefit of the Milky Way surveys is that it is also possible to study the chemistry of entire core and clump populations within a single cloud. We used the 10m Heinrich Hertz Submillimeter Telescope to survey starless clump candidates in the First Quadrant identified from the Bolocam Galactic Plane Survey 1.1 mm continuum in the deuterated molecular transitions of DCO+ 3-2 and N2D+ 3-2. We also survey the entire clump population of the Gemini OB1 molecular cloud. In both surveys, we compared detection statistics and compare deuteration fraction to physical properties of the clumps and their evolutionary stage. High resolution ALMA observations of 9 starless clump candidates of the same lines are used to analyze how the cold deuterated gas is spatially distributed in these clumps.

  11. Labelling by deuteration and nitroxide radicals of mono-, oligo- and polysaccharides (cellulose and amylose)

    Energy Technology Data Exchange (ETDEWEB)

    Odier, L

    1975-01-01

    The application of NMR and deuteration labelling to the investigation of polysaccharides has led to considerable progress in recent years in the knowledge of these compounds. Although far more recent, the introduction of spin labelling techniques in the investigation of polymers, has given rise to interesting EPR studies of synthetic and natural macromolecules, but nothing appears to have been accomplished in the area of spin labelling of polysaccharides. This work was aimed at applying these two techniques to the study of glucose derivatives and of some of its oligomers (low molecular weight polymers): cellobiose, maltose and cyclodextrins; and its polymers: cellulose and amylose. Irrespective of the technique employed, the complexity of the polymers and problems connected with handling them always require the same procedure: an initial study of a model compound generally prepared from the monomer or an oligomer (dimer), followed by the oligomers, and finally the polymer. Part 1 is devoted to the deuteration labelling of mono- and oligosaccharides. Part 2 concerns spin labelling of cellulose acetate. In part 3, an attempt is made to apply the spin labelling technique to the determination of conformations of two disaccharides of different glycosidic configurations: cellobiose and maltose. Part 4 is devoted to spin and deuteration labelling of ..cap alpha.. and ..beta.. cyclodextrins.

  12. Stereospecific assignments of glycine in proteins by stereospecific deuteration and {sup 15}N labeling

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, A.P.; Curley, R.W. Jr.; Panigot, M.J.; Fesik, S.W. [Ohio State Univ., Columbus, OH (United States)

    1994-12-01

    Stereospecific assignments are important for accurately determining the three-dimensional structures of proteins through the use of multidimensional NMR techniques. It is especially important to stereospecifically assign the glycine {alpha}-protons in proteins because of the potential for different backbone conformations of this residue. These stereospecific assignments are critical for interpreting the {sup 3}J{sub NH,{alpha}H} coupling constants and NOEs involving the glycine {alpha}-protons that determine the conformation of this part of the protein. However, it is often difficult to unambiguously obtain the stereospecific assignments for glycine residues by using only NOE data. In this poster, we present a method for unambiguous, stereospecific assignment of the {alpha}-protons of glycine residues. This method involves synthesis of stereo-specifically deuterated and {sup 15}N-labeled Gly using a slightly modified procedure originally described by Woodard and coworkers for the stereoselective deuteration of glycine. The stereospecifically deuterated and {sup 15}N-labeled Gy has been incorporated into recombinant proteins expressed in both bacterial systems (FKBP) and mammalian cells (u-PA). Two- and three-dimensional isotope-filtered and isotope-edited NMR experiments were used to obtain the stereospecific assignments of the glycine {alpha}-protons for these proteins.

  13. Labelled compounds of interest as antitumour agents. Pt. 4: Deuteration and tritiation of a nitroimidazole-carborane designed for BNCT

    International Nuclear Information System (INIS)

    Scobie, Martin; Bew, S.P.; Threadgill, M.D.

    1994-01-01

    Quenching the anion generated from a 2-(ω-carboranylalkyl)dithiane with 2 H 2 O at -78 o C and at 0 o C introduced deuterium exclusively at C-2 of the carborane. Extension of this model reaction to a bioreductively-targetted carborane allowed the synthesis of 2-[ 2 H]- and 2-[ 3 H]-isotopomers of a nitroimidazole-carborane which is of interest in boron neutron capture therapy (BNCT) of cancer. (author)

  14. Threshold Photoelectron Spectroscopy of the Methyl Radical Isotopomers, CH3, CH2D, CHD2 and CD3: Synergy between VUV Synchrotron Radiation Experiments and Explicitly Correlated Coupled Cluster Calculations

    Czech Academy of Sciences Publication Activity Database

    Cunha de Miranda, B. K.; Alcaraz, Ch.; Elhanine, M.; Noller, B.; Hemberger, P.; Fischer, I.; Garcia, G. A.; Soldi-Lose, H.; Gans, B.; Mendes, L. A. V.; Boyé-Péronne, S.; Douin, S.; Žabka, Ján; Botschwina, P.

    2010-01-01

    Roč. 114, č. 14 (2010), s. 4818-4830 ISSN 1089-5639 Grant - others:CNRS-AVCR(FR) 20201 Institutional research plan: CEZ:AV0Z40400503 Keywords : Threshold photoelectron spectroscopy * isotopomers * clusters Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.732, year: 2010

  15. Liquid State Thermochemical Decomposition of Neat 1,3,5,5-Tetranitrohexahydropyrimidine (DNNC) and its DNNC-d2, DNNC-d4, DNNC-d6 Structural Isotopomers: Mechanistic Entrance into the DNNC Molecule (Preprint)

    National Research Council Canada - National Science Library

    Shackelford, S. A; Menapace, J. A; Goldman, J. F

    2007-01-01

    ... decomposition process. Using IDSC-based KDIE comparisons with the DNNC-d2, DNNC-d4, and DNNC-d6 isotopomers, a more detailed chemical structure/mechanistic relationship emerged by entering the interior of the DNNC molecule...

  16. Liquid State Thermochemical Decomposition of Neat 1,3,5,5-Tetranitrohexahydropyrimidine (DNNC) and its DNNC-d2, DNNC-d4, DNNC-d6 Structural Isotopomers: Mechanistic Entrance into the DNNC Molecule

    National Research Council Canada - National Science Library

    Shackelford, S. A; Menapace, J. A; Goldman, J. F

    2007-01-01

    ... thermochemical decomposition process. Using IDSC-based KDIE comparisons with the DNNC-d2, DNNC-d4, and DNNC-d6 isotopomers, a more detailed chemical structure/mechanistic relationship emerged by entering the interior of the DNNC molecule...

  17. Deuteration of ammonia in the starless core Ophiuchus/H-MM1

    Science.gov (United States)

    Harju, J.; Daniel, F.; Sipilä, O.; Caselli, P.; Pineda, J. E.; Friesen, R. K.; Punanova, A.; Güsten, R.; Wiesenfeld, L.; Myers, P. C.; Faure, A.; Hily-Blant, P.; Rist, C.; Rosolowsky, E.; Schlemmer, S.; Shirley, Y. L.

    2017-04-01

    Context. Ammonia and its deuterated isotopologues probe physical conditions in dense molecular cloud cores. The time-dependence of deuterium fractionation and the relative abundances of different nuclear spin modifications are supposed to provide a means of determining the evolutionary stages of these objects. Aims: We aim to test the current understanding of spin-state chemistry of deuterated species by determining the abundances and spin ratios of NH2D, NHD2 and ND3 in a quiescent, dense cloud. Methods: Spectral lines of NH3, NH2D, NHD2, ND3 and N2D+ were observed towards a dense, starless core in Ophiuchus with the APEX, GBT and IRAM 30-m telescopes. The observations were interpreted using a gas-grain chemistry model combined with radiative transfer calculations. The chemistry model distinguishes between the different nuclear spin states of light hydrogen molecules, ammonia and their deuterated forms. Different desorption schemes can be considered. Results: High deuterium fractionation ratios with NH2D/NH3 0.4, NHD2/ NH2D 0.2 and ND3/ NHD2 0.06 are found in the core. The observed ortho/para ratios of NH2D and NHD2 are close to the corresponding nuclear spin statistical weights. The chemistry model can approximately reproduce the observed abundances, but consistently predicts too low ortho/para-NH2D, and too large ortho/para-NHD2 ratios. The longevity of N2H+ and NH3 in dense gas, which is prerequisite to their strong deuteration, can be attributed to the chemical inertia of N2 on grain surfaces. Conclusions: The discrepancies between the chemistry model and the observations are likely to be caused by the fact that the model assumes complete scrambling in principal gas-phase deuteration reactions of ammonia, which means that all the nuclei are mixed in reactive collisions. If, instead, these reactions occur through proton hop/hydrogen abstraction processes, statistical spin ratios are to be expected. The present results suggest that while the deuteration of

  18. Neutron diffraction study of crystal structures of deuterated glycinium phosphite in paraelectric and ferroelectric phases

    International Nuclear Information System (INIS)

    Machida, Mitsuo; Uchida, Hiroyuki; Ishibashi, Toku; Taniguchi, Hiroki; Komukae, Masaru; Osaka, Toshio; Koyano, Nobumitsu

    2004-01-01

    Crystal structure of deuterated glycinium phosphite was studied in the paraelectric (P) phase at 348 K and in the ferroelectric (F) phase at 223 K by means of the single crystal neutron diffraction. Deuteration rate is estimated to be 0.939 by the least-squares refinement. In the P phase, quasi-one-dimensional hydrogen bond chains are built by mutually linking the DPO 3 2- anions through two different types of hydrogen bonds with the bond angles of 179.2 and 171.6deg. Two independent deuterons within the hydrogen bonds forming the chains are disordered over two sites separated by 0.545 and 0.539A. In the F phase, they order at a position nearly equal to one of two sites related by the disorder in the P phase. With the ordering of the deuterons, the P-O bonds with covalently bonded deuteron elongate, and those without covalently bonded deuteron reduce their lengths to some extend from the values determined in the P phase. Two oxygens involved in the hydrogen bond with the bond angle 179.2deg exhibits especially large displacements in the F phase. This suggests strongly an importance of this hydrogen bond in the polarization appearance and in the ferroelectric transition. Comparison with results of non-deuterated salt indicates that only the hydrogen bonds forming the chains show significant isotope shift. In particular, the hydrogen bond with the bond angle 179.2deg exhibits the most pronounced shift on the angle parameter defined by the angle between the line connecting two sites of disordered proton or deuteron and the line connecting two oxygens involved in the hydrogen bond. (author)

  19. Widespread deuteration across the IRDC G035.39-00.33

    Science.gov (United States)

    Barnes, A. T.; Kong, S.; Tan, J. C.; Henshaw, J. D.; Caselli, P.; Jiménez-Serra, I.; Fontani, F.

    2016-05-01

    Infrared Dark Clouds (IRDCs) are cold, dense regions that are usually found within Giant Molecular Clouds. Ongoing star formation within IRDCs is typically still deeply embedded within the surrounding molecular gas. Characterizing the properties of relatively quiescent IRDCs may therefore help us to understand the earliest phases of the star formation process. Studies of local molecular clouds have revealed that deuterated species are enhanced in the earliest phases of star formation. In this paper, we test this towards IRDC G035.39-00.33. We present an 80 arcsec by 140 arcsec map of the J = 2 → 1 transition of N2D+, obtained with the Institut de Radioastronomie Millimétrique 30 m telescope telescope. We find that N2D+ is widespread throughout G035.39-00.33. Complementary observations of N2H+ (1 - 0) are used to estimate the deuterium fraction, D_frac^N_2H^+ ≡ N(N2D+)/N(N2H+). We report a mean D_frac^N_2H^+ = 0.04 ± 0.01, with a maximum of D_frac^N_2H^+ = 0.09 ± 0.02. The mean deuterium fraction is ˜3 orders of magnitude greater than the interstellar [D]/[H] ratio. High angular resolution observations are required to exclude beam dilution effects of compact deuterated cores. Using chemical modelling, we find that the average observed values of D_frac^N_2H^+are in agreement with an equilibrium deuterium fraction, given the general properties of the cloud. This implies that the IRDC is at least ˜3 Myr old, which is ˜8 times longer than the mean free-fall time of the observed deuterated region.

  20. Fibronectin distribution in the extracellular matrix in the cells grown in deuterated media

    International Nuclear Information System (INIS)

    Buzgariu, Wanda; Caloianu, Maria; Moldovan, Lucia; Stefanescu, I.; Titescu, Gh.

    2003-01-01

    The aim of this work is the study of the influence of deuterated water upon the synthesis and organization of fibronectin (FN) in extracellular matrices. Changes were evidenced at the level of extracellular matrix in case of embryo fibroblast cultivation in media with different concentrations of heavy water (20%, 40% and 65%). FN was identified in the extracellular matrix by means of indirect immunocytochemical technique, using a secondary antibody coupled with peroxydase. In the presence of heavy water in culture medium, the arrangement and localization of cellular FN showed changes depending on the exposure time, D 2 O concentration in the medium and the FN polymerization step in the extra cellular matrix in correlation with the culture stage of the monolayer. The heavy water determined a strong reduction of the FN amount released by the cells. This reduction was most evident in the 65% D 2 O medium following a 5 day exposure. The FN distribution after 2 day exposure in an early stage with regards to the FN network formation in a the deuterated medium presented a FN pericellular distribution arranged in aggregates. The heavy water can act upon formation of FN fibrils immediately due to solvent role in the FN polymerization process but also indirectly through metabolic processes and so upon the protein synthesis and FN cellular secretion.The FN network arrangement in the cells cultivated in deuterated media as aggregates might be the effect of solvent role played by D 2 O while the quantitative reduction of FN results from perturbation of protein synthesis as well from biochemical synthesis reactions

  1. D/H isotope effects in π-complexes of deuterated hexamethylbenzenes with the nitrosonium cation

    International Nuclear Information System (INIS)

    Borodkin, G.I.; Elanov, I.R.; Shakirov, M.M.; Shubin, V.G.

    1993-01-01

    The isotope effects of deuterium, manifested in the 13 C NMR spectra of complexes of deuterated hexamethylbenzenes C 6 (CD 3 ) n ·(CH 3 ) 6-n with the nitrosonium cation, have been studied. The small values observed for the isotopic perturbation are evidence of π-bonding of the NO + group to the hexamethylbenzene molecule. The applicability of an additive scheme of calculation of isotope effects for the ring carbon atoms of the complexes, based on the increment of replacement of the CH 3 group by CD 3 in hexamethylbenzene, has been demonstrated

  2. A convenient synthesis of deuterated leukotriene A sub 4 methyl ester

    Energy Technology Data Exchange (ETDEWEB)

    Bestmann, H.J.; Roeder, T. (Erlangen-Nuernberg Univ., Erlangen (Germany, F.R.). Inst. fuer Organische Chemie); Meese, C.O. (Fischer-Bosch-Inst. fuer Klinische Pharmakologie, Stuttgart (Germany, F.R.))

    1989-11-01

    2,2,3,3-({sup 2}H{sub 4})-1-Iodopentane was prepared in four steps from propargyl alcohol and used in the C-alkylation of the THP-protected 3-butyne-1-ol. Subsequent protective group removal, semi-deuteration of the acetylenic alcohol and further transformation by known methods afforded the labelled key reagent 3,4,6,6,7,7-({sup 2}H{sub 6})-(Z)-(3-nonen-1-yl)triphenylphosphonium iodide. Wittig olefination of epoxy dienal with the ylide generated from the latter completed the convenient synthesis of hexadeuterated leukotriene A{sub 4} methyl ester. (author).

  3. Effects of deuterated water upon specific activity of some marker enzymes for cytosol and plasmatic membrane

    International Nuclear Information System (INIS)

    Buzgariu, Wanda; Coroiu, Viorica; Moldovan, Lucia; Titescu, G.; Stefanescu, I.

    2004-01-01

    Recently, numerous studies were devoted to the effects of an increased environmental deuterium concentration on physiological characteristics of various biological systems, from monocellular organisms up to mammals. Within these preoccupations the experiments on enzyme activity and parameters are of special interest since they throw light upon the mechanisms in metabolic biochemical reactions (glycolysis, photosynthesis, transport across membranes, etc). The present work concerns the effects of heavy water upon the activity of some enzymes (dehydrogenase-LDH lactate and 5' nucleotidase) implied in different metabolic pathways, serving as functional indicators for some cellular compartments such as the cytosols and cellular membranes. Enzyme activity was determined by growing for 6 days the cells (Hep 2, CHO, fibroblasts) in deuterated culture media at different concentration levels (20%, 40%, 65% si 90%), as well as in a reaction medium deuterated at 99.96%. In case of the first experimental run the LDH activity was monitored for the three cellular lines (Hep 2, CHO, fibroblasts) for different time intervals (1 d, 3 d and 6 d). After the first 24 h of cells' exposure the activity values were similar regardless of the heavy water concentration in the medium. Exposing the cells for longer time (6 days) led to modifications of LDH activity. In contrast to the case of media with relatively moderate D 2 O content, cell growing in conditions of intense deuteration 65% and 90 % D 2 O) led to an increase of cytosolic enzyme activity of about 50%. In case of 5' nucleotidase after 6 days of cell cultivation in deuteration conditions the activity decreased to 50% and 70% from the value corresponding to normal conditions for cell growth. This diminution of the activity was characteristic for the media with 65% and 90% D 2 O. In the second experimental run the activities of dehydrogenase lactate and 5' nucleotidase from the cellular homogenate obtained from cells grown in

  4. Partially-deuterated samples of HET-s(218–289) fibrils: assignment and deuterium isotope effect

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Albert A.; Ravotti, Francesco; Testori, Emilie; Cadalbert, Riccardo; Ernst, Matthias, E-mail: maer@ethz.ch [ETH Zürich, Physical Chemistry (Switzerland); Böckmann, Anja, E-mail: a.bockmann@ibcp.fr [Institut de Biologie et Chimie des Protéines, Bases Moléculaires et Structurales des Systèmes Infectieux, Labex Ecofect, UMR 5086 CNRS, Université de Lyon (France); Meier, Beat H., E-mail: beme@ethz.ch [ETH Zürich, Physical Chemistry (Switzerland)

    2017-02-15

    Fast magic-angle spinning and partial sample deuteration allows direct detection of {sup 1}H in solid-state NMR, yielding significant gains in mass sensitivity. In order to further analyze the spectra, {sup 1}H detection requires assignment of the {sup 1}H resonances. In this work, resonance assignments of backbone H{sup N} and Hα are presented for HET-s(218–289) fibrils, based on the existing assignment of Cα, Cβ, C’, and N resonances. The samples used are partially deuterated for higher spectral resolution, and the shifts in resonance frequencies of Cα and Cβ due to the deuterium isotope effect are investigated. It is shown that the deuterium isotope effect can be estimated and used for assigning resonances of deuterated samples in solid-state NMR, based on known resonances of the protonated protein.

  5. Deuteration of metals through electric discharges; Deuteracion de metales bajo descargas electricas

    Energy Technology Data Exchange (ETDEWEB)

    Balderas G, L M

    1996-12-31

    In this work deuteration of titanium and a stainless steel through electrical discharges in a vacuum chamber was performed at different thermodynamic conditions. The samples were plates of 0.03 x 4.5 x 54 cm. The titanium sample was first cleaning with chloroform. The oxide layer was removed by cleaning the sample with a 1:1:1 mixture of water, nitric acid and sulphuric acid. Later was rinsed in water and dried with acetone. Finally, was treated with HCl to form an hydride layer on the surface. The stainless steel sample was only cleaned with soap and cleaning with acetone. The samples were cleaning at low pressure for several days with high temperature short cycles. The deuterium was loaded to the chamber at room temperature having absorption on the titanium samples at 10{sup 3} at 10{sup 1} mbar. Afterwards that the samples were heated up at 330 C and was observed the deuterium absorption in the same pressure range. Forced deuteration through electrical discharges between the sample and the chamber was tried obtaining absorption in the range of 10{sup 3} at 10{sup 2} mbar, however the deuterium absorption only was observed in specific cases. In order to detect neutron emission or released particles in this experiment were used alanine detectors and series of plastic CR-39 and borate films. No neutron were detected in the passive systems used in the experiments. (Author).

  6. Isotopic fractionation of fentanyl and its deuterated analogues by capillary gas chromatography

    International Nuclear Information System (INIS)

    Sera, Shoji; Goromaru, Tsuyoshi

    1997-01-01

    Isotopic fractionation of fentanyl (FT) and its deuterated analogues by gas chromatography using capillary columns (CBP1 and CBP5) has been investigated. Seven kinds of analogues were labeled with 5 to 19 deuterium atoms at the anilino, propionyl and/or phenylethyl group of FT. The retention times of deuterated FT in CBP1 and CBP5 columns are inversely proportional to the number of labeled deuterium atoms in the molecule. The difference in free enegy changes (ΔΔG) had a linear relationship with the number of labeled deuterium atoms, except for labeling at anilino and phenylethyl group. The contribution of a deuterium atom to the ΔΔG value was estimated to be 1.13 cal/mol in CBP1 and 1.40 cal/mol in CBP5, respectively. While, its contribution in the propiony group was 2.84 cal/mol in CBP1 and 2.48 cal/mol in CBP5, respectively. An important factor in separation by GC may differences in interactions between the stationary phase of the column with the three dimensional protrusive moiety in the molecule. (author)

  7. Isotopic fractionation of fentanyl and its deuterated analogues by capillary gas chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Sera, Shoji; Goromaru, Tsuyoshi [Fukuyama Univ., Hiroshima (Japan)

    1997-12-01

    Isotopic fractionation of fentanyl (FT) and its deuterated analogues by gas chromatography using capillary columns (CBP1 and CBP5) has been investigated. Seven kinds of analogues were labeled with 5 to 19 deuterium atoms at the anilino, propionyl and/or phenylethyl group of FT. The retention times of deuterated FT in CBP1 and CBP5 columns are inversely proportional to the number of labeled deuterium atoms in the molecule. The difference in free enegy changes ({Delta}{Delta}G) had a linear relationship with the number of labeled deuterium atoms, except for labeling at anilino and phenylethyl group. The contribution of a deuterium atom to the {Delta}{Delta}G value was estimated to be 1.13 cal/mol in CBP1 and 1.40 cal/mol in CBP5, respectively. While, its contribution in the propiony group was 2.84 cal/mol in CBP1 and 2.48 cal/mol in CBP5, respectively. An important factor in separation by GC may differences in interactions between the stationary phase of the column with the three dimensional protrusive moiety in the molecule. (author)

  8. Study of deuterated water in the low-mass protostar IRAS16293-2422

    Science.gov (United States)

    Coutens, A.; Vastel, C.; Caux, E.; Ceccarelli, C.; Herschel Chess Team

    2011-05-01

    Observations of deuterated water are an important complement for studies of H2O, since they give strong constraints on the formation processes: grain surfaces versus gas-phase chemistry through energetic process as shocks. The CHESS (Chemical HErschel Surveys of Star forming regions) Key Program has allowed to detect a lot of transitions of HDO (8) and H2O (16) as well as its isotopes H_218O and H_217O towards the low-mass protostar IRAS16293-2422 thanks to the unbiaised spectral survey carried out with the HIFI instrument on board the Herschel Space Observatory. Complementary data of HDO from the ground-based telescopes IRAM and JCMT are also available, allowing a precise determination of the abundance of deuterated water through the protostar envelope. In order to reproduce the observed line profiles, we have performed a modeling of HDO from the hot corino through the envelope using the physical structure of the protostar (Crimier et al. 2010) and the spherical Monte Carlo radiative transfer code RATRAN, which takes also into account radiative pumping by continuum emission from dust. We have used new HDO collision rates with H_2, recently computed by Wiesenfeld, Scribano and Faure (2011, PCCP). The same method has been applied to model H_2O and its isotopes H_218O and H_217O. We will present the results of this analysis and discuss the determined abundances.

  9. Static structure factor of polymerlike micelles: Overall dimension, flexibility, and local properties of lecithin reverse micelles in deuterated isooctane

    DEFF Research Database (Denmark)

    Jerke, G.; Pedersen, J.S.; Egelhaaf, S.U.

    1997-01-01

    We report a systematic investigation of the static structure factor S(q,c) of polymerlike reverse micelles formed by soybean lecithin and trace amounts of water in deuterated isooctane using small-angle neutron scattering and static light scattering. The experimental data for different concentrat......We report a systematic investigation of the static structure factor S(q,c) of polymerlike reverse micelles formed by soybean lecithin and trace amounts of water in deuterated isooctane using small-angle neutron scattering and static light scattering. The experimental data for different...

  10. Synthesis and spectroscopic stereospecificity assay of the deuterated quinolizidine alkaloids (2S)-[2H]- and (2R)-[2H]-sparteine

    International Nuclear Information System (INIS)

    Ebner, T.; Meese, C.O.; Rebell, J.

    1989-01-01

    Borohydride reduction of the (+)-1,2-dehydrosparteinium salts proceeds almost exclusively from the Si side, yielding, respectively, the stereoselectively (2S)(β)-deuterated (-)-sparteine and the (2R)(α)-deuterated (-)-sparteine. Stereo-chemistry and isotopic purity of the deuterium label (≥98%) are established unequivocally by 1 H, 2 H and 13 C NMR spectroscopy. (author)

  11. Synthesis and spectroscopic stereospecificity assay of the deuterated quinolizidine alkaloids (2S)-( sup 2 H)- and (2R)-( sup 2 H)-sparteine

    Energy Technology Data Exchange (ETDEWEB)

    Ebner, T.; Meese, C.O. (Fischer-Bosch Inst. fuer Klinische Pharmakologie, Stuttgart (Germany, F.R.)); Rebell, J. (Stuttgart Univ. (Germany, F.R.). Inst. fuer Organische Chemie); Fischer, P. (Stuttgart Univ. (Germany, F.R.). Inst. fuer Organische Chemie Fischer-Bosch Inst. fuer Klinische Pharmakologie, Stuttgart (Germany, F.R.))

    1989-04-01

    Borohydride reduction of the (+)-1,2-dehydrosparteinium salts proceeds almost exclusively from the Si side, yielding, respectively, the stereoselectively (2S)({beta})-deuterated (-)-sparteine and the (2R)({alpha})-deuterated (-)-sparteine. Stereo-chemistry and isotopic purity of the deuterium label ({>=}98%) are established unequivocally by {sup 1}H, {sup 2}H and {sup 13}C NMR spectroscopy. (author).

  12. Deuterated water in the solar-type protostars NGC 1333 IRAS 4A and IRAS 4B

    NARCIS (Netherlands)

    Coutens, A.; Vastel, C.; Cabrit, S.; Codella, C.; Kristensen, L. E.; Ceccarelli, C.; van Dishoeck, E. F.; Boogert, A. C. A.; Bottinelli, S.; Castets, A.; Caux, E.; Comito, C.; Demyk, K.; Herpin, F.; Lefloch, B.; McCoey, C.; Mottram, J. C.; Parise, B.; Taquet, V.; van der Tak, F. F. S.; Visser, R.; Yıldız, U. A.

    2013-01-01

    Context. The measure of the water deuterium fractionation is a relevant tool for understanding mechanisms of water formation and evolution from the prestellar phase to the formation of planets and comets. Aims: The aim of this paper is to study deuterated water in the solar-type protostars NGC 1333

  13. Selective deuteration illuminates the importance of tunneling in the unimolecular decay of Criegee intermediates to hydroxyl radical products.

    Science.gov (United States)

    Green, Amy M; Barber, Victoria P; Fang, Yi; Klippenstein, Stephen J; Lester, Marsha I

    2017-11-21

    Ozonolysis of alkenes, an important nonphotolytic source of hydroxyl (OH) radicals in the atmosphere, proceeds through unimolecular decay of Criegee intermediates. Here, we report a large kinetic isotope effect associated with the rate-limiting hydrogen-transfer step that releases OH radicals for a prototypical Criegee intermediate, CH 3 CHOO. IR excitation of selectively deuterated syn -CD 3 CHOO is shown to result in deuterium atom transfer and release OD radical products. Vibrational activation of syn -CD 3 CHOO is coupled with direct time-resolved detection of OD products to measure a 10-fold slower rate of unimolecular decay upon deuteration in the vicinity of the transition state barrier, which is confirmed by microcanonical statistical theory that incorporates quantum mechanical tunneling. The corresponding kinetic isotope effect of ∼10 is attributed primarily to the decreased probability of D-atom vs. H-atom transfer arising from tunneling. Master equation modeling is utilized to compute the thermal unimolecular decay rates for selectively and fully deuterated syn methyl-substituted Criegee intermediates under atmospheric conditions. At 298 K (1 atm), tunneling is predicted to enhance the thermal decay rate of syn -CH 3 CHOO compared with the deuterated species, giving rise to a significant kinetic isotope effect of ∼50.

  14. Neutronic measurements on electrolytic cells with deuterated palladium in a submarine environment

    International Nuclear Information System (INIS)

    Granada, J.R.; Mayer, R.E.; Florido, P.C.; Gillette, V.H.; Gomez, S.E.

    1990-01-01

    Using a high efficiency system for the neutron thermal detection and a pulsed electrolytic current procedure, measurements were made on cells containing Pd cathodes and electrolytes at a D 2 O and H 2 O base. The peculiarity of these experiments is that they were carried out on board of the A.R.A. Santa Cruz submarine, at a depth of 50m under sea level, attaining ultra deep-down conditions in the measurements, corresponding to a reduction in a factor = 50 in relation to lab conditions. The mean level of the signal -obtained from counting combination of deuterated cathodes- results to be separated from the deep-down level by four standard deviations. (Author) [es

  15. Gas Chromatographic Mass Spectrometric Determination of Myo-inositol in Humans Utilizing a Deuterated Internal Standard

    DEFF Research Database (Denmark)

    Andersen, Jan Rud; Larsen, Elfinn; Harbo, Helge

    1982-01-01

    The isotopic dilution technique was used for determining the content of myo-inositol in human urine, plasma and haemolysed erythrocyte samples. A deuterated myo-inositol, synthesized from inosose-2 by base-catalysed exchange of hydrogens by deuterium, followed by reduction of the inosose with 2H2......, was added as internal standard to the samples at an early stage in the analytical procedure. After separation and derivatization to the hexa-acetate, the gas chromatographic mass spectrometric analysis was carried out. A 25 m fused silica capillary column coated with methyl silicone was used, and the ions...... selected for monitoring were m/z 210 and m/z 214, which are characteristic and abundant fragment ions from unlabelled and hexadeuterated myo-inositolhexa-acetate, respectively. Calibration curves from water, urine, plasma and haemolysed erythrocytes show parallel, linear responses in the ratio between...

  16. OD bands in the IR spectra of a deuterated soda-lime-silica glass

    Energy Technology Data Exchange (ETDEWEB)

    Peuker, C.; Brzezinka, K.W.; Gaber, M.; Kohl, A.; Geissler, H. [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany)

    2001-07-01

    IR spectra of a deuterated glass of the composition (in mol%) 16 Na{sub 2}O . 10 CaO . 74 SiO{sub 2} complete earlier spectroscopic studies on water-poor soda-lime-silica glasses. The approved IR spectroscopic method of the deuterium exchange allows a reliable assignment of the hydroxyl bands also in the case of glasses. By spectra comparison the assignment of the IR bands at 3500 and 2800 cm{sup -1} to hydroxyl groups with different hydrogen bonding is verified. The IR band at about 4500 cm{sup -1} is interpreted as both a combination of the stretching vibrations {nu}O-H and {nu}Si-OH and a combination of the stretching vibration {nu}O-H and the deformation vibration {delta}SiOH. The bands at 1763 and 1602 cm{sup -1} are attributed to combination vibrations of the glass network. (orig.)

  17. Crystal structures and phase transformation of deuterated lithium imide, Li2ND

    International Nuclear Information System (INIS)

    Balogh, Michael P.; Jones, Camille Y.; Herbst, J.F.; Hector, Louis G.; Kundrat, Matthew

    2006-01-01

    We have investigated the crystal structure of deuterated lithium imide, Li 2 ND, by means of neutron and X-ray diffraction. An order-disorder transition occurs near 360K. Below that temperature Li 2 ND can be described to the same level of accuracy as a disordered cubic (Fd3-bar m) structure with partially occupied Li 32e sites or as a fully occupied orthorhombic (Ima2 or Imm2) structure. The high temperature phase is best characterized as disordered cubic (Fm3-bar m) with D atoms randomized over the 192l sites. Density functional theory calculations complement and support the diffraction analyses. We compare our findings in detail with previous studies

  18. Water deuteration in star-forming regions: Contribution of Herschel/HIFI spectroscopic data

    International Nuclear Information System (INIS)

    Coutens, Audrey

    2012-01-01

    Water (H_2O) is one of the most abundant molecules in the interstellar medium. In addition to being a primordial ingredient in the emergence of life, this species plays an essential role in the process of star formation through the cooling of warm gas. It also controls the chemistry for many species, either in the gas phase or on the grain surfaces. Studying its deuterated form HDO is a unique opportunity, through the estimation of the HDO/H_2O ratio, to constrain the mechanisms of water formation and to better understand the origin of water contained in terrestrial oceans. Indeed, recent results obtained with the Herschel satellite show that the HDO/H_2O ratio observed in comets is similar to the value measured in oceans (∼1.5 10"-"4), which suggests that comets could have brought a large fraction to Earth to form the oceans during heavy bombardments (Hartogh et al. 2011). In this thesis, I was interested in the study of deuterated water in the first stages of star formation, the Class 0 stage, which precede the formation of the protoplanetary disk leading to the birth of comets and planets. Through a 1D non-Local Thermodynamic Equilibrium radiative transfer modeling of the line profiles of the numerous HDO and H_2"1"8O transitions detected with the HIFI (Heterodyne Instrument for Far-Infrared) instrument onboard the Herschel Space Observatory and ground-based telescopes (IRAM, JCMT), I determined that the HDO/H_2O ratios of the solar-type protostar IRAS 16293-2422 was about 2% in the hot corino, the inner part of the protostellar envelope sufficiently warm (T ≥ 100 K) to desorb in gas phase the water molecules trapped in the icy grain mantles, and about 0.5% in the colder part of the envelope. This study (Coutens et al. 2012) also allowed me to show that an absorbing layer rich in water surrounds the protostar. This layer could be produced by the photo-desorption through the UV field of the water molecules frozen on the grains, on the edges of the molecular

  19. Effect of N-methyl deuteration on metabolism and pharmacokinetics of enzalutamide

    Directory of Open Access Journals (Sweden)

    Jiang J

    2016-07-01

    Full Text Available Jinfang Jiang,1,2,* Xuehai Pang,2,3,* Liang Li,1,2 Xiaojian Dai,1,2 Xingxing Diao,1 Xiaoyan Chen,1,2 Dafang Zhong,1,2 Yingwei Wang,2,3 Yuanwei Chen2–4 1State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 2University of Chinese Academy of Sciences, Beijing, 3Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, 4Hinova Pharmaceuticals Inc, Chengdu, People’s Republic of China *These authors contributed equally to this work Background: The replacement of hydrogen with deuterium invokes a kinetic isotope effect. Thus, this method is an attractive way to slow down the metabolic rate and modulate pharmacokinetics.Purpose: Enzalutamide (ENT acts as a competitive inhibitor of the androgen receptor and has been approved for the treatment of metastatic castration-resistant prostate cancer by the US Food and Drug Administration in 2012. To attenuate the N-demethylation pathway, hydrogen atoms of the N–CH3 moiety were replaced by the relatively stable isotope deuterium, which showed similar pharmacological activities but exhibited favorable pharmacokinetic properties.Methods: We estimated in vitro and in vivo pharmacokinetic parameters for ENT and its deuterated analog (d3-ENT. For in vitro studies, intrinsic primary isotope effects (KH/KD were determined by the ratio of intrinsic clearance (CLint obtained for ENT and d3-ENT. The CLint values were obtained by the substrate depletion method. For in vivo studies, ENT and d3-ENT were orally given to male Sprague Dawley rats separately and simultaneously to assess the disposition and metabolism of them. We also investigated the main metabolic pathway of ENT by comparing the rate of oxidation and hydrolysis in vitro. Results: The in vitro CLint (maximum velocity/Michaelis constant [Vmax/Km] of d3-ENT in rat and human liver microsomes were 49.7% and 72.9% lower than those of the non-deuterated compound, corresponding to the KH

  20. Deuterated silicon nitride photonic devices for broadband optical frequency comb generation

    Science.gov (United States)

    Chiles, Jeff; Nader, Nima; Hickstein, Daniel D.; Yu, Su Peng; Briles, Travis Crain; Carlson, David; Jung, Hojoong; Shainline, Jeffrey M.; Diddams, Scott; Papp, Scott B.; Nam, Sae Woo; Mirin, Richard P.

    2018-04-01

    We report and characterize low-temperature, plasma-deposited deuterated silicon nitride thin films for nonlinear integrated photonics. With a peak processing temperature less than 300$^\\circ$C, it is back-end compatible with pre-processed CMOS substrates. We achieve microresonators with a quality factor of up to $1.6\\times 10^6 $ at 1552 nm, and $>1.2\\times 10^6$ throughout $\\lambda$ = 1510 -- 1600 nm, without annealing or stress management. We then demonstrate the immediate utility of this platform in nonlinear photonics by generating a 1 THz free spectral range, 900-nm-bandwidth modulation-instability microresonator Kerr comb and octave-spanning, supercontinuum-broadened spectra.

  1. Intense deuterium nuclear fusion of pycnodeuterium-lumps coagulated locally within highly deuterated atom clusters

    CERN Document Server

    Yoshiaki, A; Zhang, Y C

    2002-01-01

    Embedded nano-Pd particles of 5 nm in size instantly abundant D-atoms more than 250% in the atomic ratio against Pd-atoms at room temperature when they are kept in D sub 2 gas pressurized to less than 10 atm. In such ultrahigh densities, 2-4 D-atoms can be coagulated inside each octahedral space of Pd lattice (pycnodeuterium-lump). When a stimulation energy such as latticequake causing by ultrasonic wave was supplied to those highly deuterated Pd particles, intense deuterium nuclear fusion (''solid fusion'') was generated there and both excess heat and sup 4 He gas were abundantly produced. Naturally, these facts can not be realized at all in bulk Pd. The results show that the nuclear fusion occurs without any hazardous rays in pycnodeuterium-lumps coagulated locally inside the each cell of the host metal lattice. These unit cells correspond to minimum unit of the solid fusion reactor as a ''Lattice Reactor''. (author)

  2. Chemical shift assignments of the partially deuterated Fyn SH2-SH3 domain.

    Science.gov (United States)

    Kieken, Fabien; Loth, Karine; van Nuland, Nico; Tompa, Peter; Lenaerts, Tom

    2018-04-01

    Src Homology 2 and 3 (SH2 and SH3) are two key protein interaction modules involved in regulating the activity of many proteins such as tyrosine kinases and phosphatases by respective recognition of phosphotyrosine and proline-rich regions. In the Src family kinases, the inactive state of the protein is the direct result of the interaction of the SH2 and the SH3 domain with intra-molecular regions, leading to a closed structure incompetent with substrate modification. Here, we report the 1 H, 15 N and 13 C backbone- and side-chain chemical shift assignments of the partially deuterated Fyn SH3-SH2 domain and structural differences between tandem and single domains. The BMRB accession number is 27165.

  3. A neutron diffraction study on deuterated Rochelle salt structure at - 195degC paraelectric phase

    International Nuclear Information System (INIS)

    Iwata, Yutaka; Mitani, Shigeshi; Fukui, Susumu; Shibuya, Iwao

    1989-01-01

    Neutron diffraction study on the low temperature paraelectric phase of Rochelle salt was performed using deuterated single crystal specimen. Large anisotropic thermal motions of atoms are found to be prevailing in the lower paraelectric phase. This indicates the disordering of atoms and the analysis by two-site split-atom method showed that a split atom model holds equally well with an ordinary non-split model. By connecting split positions selectively, a disordered paraelectric structure, which is composed of half-occupied units, was obtained. These units can be regarded as ones in the ferroelectric phase according to a deduction from an order-disorder phase transition scheme. A possibility of existence of the 'local disorder' of O(5)-H group in the tartrate molecule was examined by Fourier method and a result proved to be negative. Present disordered model gives better understanding to the phase transition scheme of Rochelle salt than the local disorder model case. (author)

  4. THE HERSCHEL AND IRAM CHESS SPECTRAL SURVEYS OF THE PROTOSTELLAR SHOCK L1157-B1: FOSSIL DEUTERATION

    International Nuclear Information System (INIS)

    Codella, C.; Fontani, F.; Vasta, M.; Ceccarelli, C.; Lefloch, B.; Kahane, C.; Taquet, V.; Wiesenfeld, L.; Busquet, G.; Caselli, P.; Lis, D.; Viti, S.

    2012-01-01

    We present the first study of deuteration toward the protostellar shock L1157-B1, based on spectral surveys performed with the Herschel-HIFI and IRAM 30 m telescopes. The L1157 outflow is driven by a low-mass Class 0 protostar and is considered the prototype of the so-called chemically active outflows. The young (2000 yr), bright blueshifted bow shock, B1, is an ideal laboratory for studying the gas chemically enriched by the release of dust mantles due to the passage of a shock. A total of 12 emission lines (up to E u = 63 K) of CH 2 DOH, HDCO, and DCN are detected. In addition, two lines of NH 2 D and HDO are tentatively reported. To estimate the deuteration, we also extracted from our spectral survey emission lines of non-deuterated isotopologues ( 13 CH 3 OH, H 2 13 CO, H 13 CN, H 2 13 CO, and NH 3 ). We infer higher deuteration fractions for CH 3 OH (D/H = 0.2-2 × 10 –2 ) and H 2 CO (5-8 × 10 –3 ) than for H 2 O (0.4-2 × 10 –3 ), HCN (∼10 –3 ), and ammonia (≤3 × 10 –2 ). The measurement of deuteration of water, formaldehyde, and methanol in L1157-B1 provides a fossil record of the gas before it was shocked by the jet driven by the protostar. A comparison with gas-grain models indicates that the gas passed through a low-density (≤10 3 cm –3 ) phase, during which the bulk of water ices formed, followed by a phase of increasing density, up to 3 × 10 4 cm –3 , during which formaldehyde and methanol ices formed.

  5. Correlation between the structure and infra-red absorption characteristics of mono-deuterated compounds: contribution to the study of organo-magnesium compounds

    International Nuclear Information System (INIS)

    Paillous, A.

    1965-10-01

    The high sensitivity of the ν (C-D) vibration to the variations brought about by the substitution of the carbon attached to the deuterium is shown in the case of organic or organo-metallic mono-deuterated molecules. In particular, syntheses of various mono-deuterated organo-magnesium compounds have been carried out; results are given concerning an infra-red spectrometric examination of these compounds in the range 2100 - 2250 cm -1 . The results show the existence of only one type of deuterated carbon, which suggests that the same carbanion is involved in various ionic associations for the different magnesium-containing compounds. (authors) [fr

  6. Functional Representation for the Born-Oppenheimer Diagonal Correction and Born-Huang Adiabatic Potential Energy Surfaces for Isotopomers of H3

    International Nuclear Information System (INIS)

    Mielke, Steven L.; Schwenke, David; Schatz, George C.; Garrett, Bruce C.; Peterson, Kirk A.

    2009-01-01

    Multireference configuration interaction (MRCI) calculations of the Born-Oppenheimer diagonal correction (BODC) for H3 were performed at 1397 symmetry-unique configurations using the Born-Huang approach; isotopic substitution leads to 4041 symmetry-unique configurations for the DH2 mass combination. These results were then fit to a functional form that permits calculation of the BODC for any combination of isotopes. Mean unsigned fitting errors on a test grid of configurations not included in the fitting process were 0.14, 0.12, and 0.65 cm-1 for the H3, DH2, and MuH2 isotopomers, respectively. This representation can be combined with any Born-Oppenheimer potential energy surface (PES) to yield Born-Huang (BH) PESs; herein we choose the CCI potential energy surface, the uncertainties of which (∼0.01 kcal/mol) are much smaller than the magnitude of the BODC. FORTRAN routines to evaluate these BH surfaces are provided. Variational transition state theory calculations are presented comparing thermal rate constants for reactions on the BO and BH surfaces to provide an initial estimate of the significance of the diagonal correction for the dynamics.

  7. The feasibility study of using deuterated gadolinium nitrate for moderator-poisoned shutdown and excess reactivity control in CANDU reactors

    International Nuclear Information System (INIS)

    Li, J.; Everatt, A.

    2006-01-01

    Gadolinium nitrate is used in CANDU stations as moderator poison for reactor shutdowns and excess reactivity control. The use of the light-water hydrate introduces significant quantities of light water into the moderator system, which must be removed from the moderator by periodically upgrading the moderator (isotopic maintenance). The benefit of using a deuterated gadolinium nitrate would be a higher moderator isotopic and/or a lesser isotopic maintenance requirement. This study evaluated the economics of using deuterated gadolinium nitrate, as opposed to the light-water hydrate, for moderator-poisoned shutdowns and excess reactivity control in CANDU-6 reactors. Normal gadolinium nitrate (i.e., the light-water hydrate) is available from suppliers at ∼125 $/kg. Supplier quotes for deuterated gadolinium nitrate ranged from 1900 to 4000 $/kg. To examine the possibility of producing deuterated gadolinium nitrate in-house at a lower cost than commercially available, a three-stage dissolution/evaporation manufacturing process was conceived and costed. Depending on the assumed demand for the product (i.e., the number of reactors adopting the use of the product) and the capital recovery period, the estimated unit cost for the dissolution/evaporation process ranged from 730 to 2500 $/kg. The determination of economic benefit from using deuterated gadolinium nitrate in existing CANDU stations was based on the cost savings resulting from a higher fuel burn-up (i.e., the higher moderator isotopic would give a higher fuel burn-up). The net benefit of using deuterated gadolinium nitrate for most CANDU stations was determined to be marginal (i.e., <20 k$/a). Only for those CANDU stations where the moderator isotopic was relatively low (e.g., 99.85 wt%) was there a potential significant benefit (20-100 k$/a). However, if the reason for the low moderator isotopic is a relatively high moderator light-water ingress rate from sources other than the use of the light-water hydrate

  8. TEM and EELS study of deuterated carbon: application to the fuel retention in tokamaks; Etude couplee MET-EELS du carbone deutere: application a la retention du combustible dans les tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Bernier, N

    2007-12-15

    We developed a methodology, based on the combination of TEM and EELS techniques, for a structural and chemical characterization, at a high spatial resolution, of a wide range of carbon materials. We i) optimized, in the framework of theoretical models, the sp2 fraction quantification from pure carbons by EELS ii) transferred this quantification to deuterated amorphous carbon layers iii) showed, from graphitized carbons, how the TEM-EELS combination allows to detect low concentrations of implanted D. Due to the accomplishment of these developments, we applied our approach to the study of D retention in composites C/C, which are the plasma-facing materials in TS. We showed that specific localized retention sites correspond to relatively large ({approx} 3 mm.) cracks between fibres and matrix; such cracks offer a simple and direct path for deuterated amorphous carbon. The particle balance performed in TS is discussed in the light of this trapping mechanism. (author)

  9. Tritium aging effect of LaNi4.9Al0.1Dx on de-deuterating kinetics

    International Nuclear Information System (INIS)

    Xiong Yifu; Luo Deli; Li Rong

    2002-01-01

    Kinetics parameters are measured at different aging times of LaNi 4.9 Al 0.1 alloy. The influence of tritium aging on kinetic feature of LaNi 4.9 Al 0.1 alloy is assessed. The results show that reaction rate decreases with aging time, but tritium aging does not change de-deuterating reaction order. De-deuterating reaction orders a (with respect to deuterium pressure) and b (with respect to deuterium content) are 0.5 and 1, respectively. Activation energy (E) increases with aging time. After 1120 d, the reaction rate constant is decreased by two orders of magnitude, activation energy is increased by a factor of 0.3

  10. Deuteration of acetanilides and other substituted aromatics using [Ir(COD)(Cy3P)(Py)]PF6 as catalyst

    International Nuclear Information System (INIS)

    Hesk, D.; Das, P.R.; Evans, B.

    1995-01-01

    Deuterium exchange labelling using [Ir(COD)(Cy 3 P)(Py)]PF 6 as catalyst and deuterium gas was studied on a number of substituted acetanilides. In most cases products containing deuterium ortho to the anilide group were obtained with a high degree of enrichment. With one exception no evidence for meta, para or anilide methyl labelling was seen. The catalyst was also effective in the ortho deuteration of acetophenone, benzophenone and the β-lactam containing compound Sch 48461. (Author)

  11. Deuteration of Dimethyl 4,4'-dimethoxy-5,6,5',6'-dimethylenedioxybiphenyl-2,2'-dicarboxylate (BDD)

    International Nuclear Information System (INIS)

    Tong Qiang

    1990-01-01

    A new antihepatitic drug, BDD(I), which is very active and powerful especially in lowering elevated SGPT levels, has been previously discovered during the systematic study of Schisandra chinensis. In order to study the metabolism of this new antihepatitic drug, deuterated BDD was prepared according to the following method. BDD 1g, sodium chloroplatinate 193 mg, deuterium oxide 16 ml, acetic anhydride 30 ml, and acetyl chloride 0.4 ml were well mixed in a sealed ampoule and heated to 120-130 deg C for 12h. The mixture was then poured into water. The precipitate (0.86g) contained the deuterated acid (IIa, IIb) of BDD. After esterification with methanol, a mixture (m.p. 150 ∼ 153 deg C) of mono-and di-deuterated BDD was obtained. Molecular clustering, as determined by GC/MS, showed that the product consisted of mono-deutero-BDD(IIIa) (m/e419) and dideutero-BDD(IIIb) (m/e420) in the ratio of 1:1.3

  12. Hexicon 2: automated processing of hydrogen-deuterium exchange mass spectrometry data with improved deuteration distribution estimation.

    Science.gov (United States)

    Lindner, Robert; Lou, Xinghua; Reinstein, Jochen; Shoeman, Robert L; Hamprecht, Fred A; Winkler, Andreas

    2014-06-01

    Hydrogen-deuterium exchange (HDX) experiments analyzed by mass spectrometry (MS) provide information about the dynamics and the solvent accessibility of protein backbone amide hydrogen atoms. Continuous improvement of MS instrumentation has contributed to the increasing popularity of this method; however, comprehensive automated data analysis is only beginning to mature. We present Hexicon 2, an automated pipeline for data analysis and visualization based on the previously published program Hexicon (Lou et al. 2010). Hexicon 2 employs the sensitive NITPICK peak detection algorithm of its predecessor in a divide-and-conquer strategy and adds new features, such as chromatogram alignment and improved peptide sequence assignment. The unique feature of deuteration distribution estimation was retained in Hexicon 2 and improved using an iterative deconvolution algorithm that is robust even to noisy data. In addition, Hexicon 2 provides a data browser that facilitates quality control and provides convenient access to common data visualization tasks. Analysis of a benchmark dataset demonstrates superior performance of Hexicon 2 compared with its predecessor in terms of deuteration centroid recovery and deuteration distribution estimation. Hexicon 2 greatly reduces data analysis time compared with manual analysis, whereas the increased number of peptides provides redundant coverage of the entire protein sequence. Hexicon 2 is a standalone application available free of charge under http://hx2.mpimf-heidelberg.mpg.de.

  13. Hexicon 2: Automated Processing of Hydrogen-Deuterium Exchange Mass Spectrometry Data with Improved Deuteration Distribution Estimation

    Science.gov (United States)

    Lindner, Robert; Lou, Xinghua; Reinstein, Jochen; Shoeman, Robert L.; Hamprecht, Fred A.; Winkler, Andreas

    2014-06-01

    Hydrogen-deuterium exchange (HDX) experiments analyzed by mass spectrometry (MS) provide information about the dynamics and the solvent accessibility of protein backbone amide hydrogen atoms. Continuous improvement of MS instrumentation has contributed to the increasing popularity of this method; however, comprehensive automated data analysis is only beginning to mature. We present Hexicon 2, an automated pipeline for data analysis and visualization based on the previously published program Hexicon (Lou et al. 2010). Hexicon 2 employs the sensitive NITPICK peak detection algorithm of its predecessor in a divide-and-conquer strategy and adds new features, such as chromatogram alignment and improved peptide sequence assignment. The unique feature of deuteration distribution estimation was retained in Hexicon 2 and improved using an iterative deconvolution algorithm that is robust even to noisy data. In addition, Hexicon 2 provides a data browser that facilitates quality control and provides convenient access to common data visualization tasks. Analysis of a benchmark dataset demonstrates superior performance of Hexicon 2 compared with its predecessor in terms of deuteration centroid recovery and deuteration distribution estimation. Hexicon 2 greatly reduces data analysis time compared with manual analysis, whereas the increased number of peptides provides redundant coverage of the entire protein sequence. Hexicon 2 is a standalone application available free of charge under http://hx2.mpimf-heidelberg.mpg.de.

  14. LIF excitation spectra for S 0 → S 1 transition of deuterated anthranilic acid COOD, ND 2 in supersonic-jet expansion

    Science.gov (United States)

    Kolek, Przemysław; Leśniewski, Sebastian; Andrzejak, Marcin; Góra, Maciej; Cias, Pawel; Weģrzynowicz, Adam; Najbar, Jan

    2010-12-01

    Laser induced fluorescence (LIF) excitation spectrum for the S 0 → S 1 transition of anthranilic acid molecules deuterated in the substituent groups (COOD, ND 2) was investigated. Analysis of the LIF spectrum allowed for the assignment of the six most prominent fundamental in-plane modes of frequencies up to ca. 850 cm. The experimental results show good correlation with the frequency changes upon deuteration computed with CIS (CI-Singles) and TD-DFT for the S 1 state. Deuteration induced red-shifts of the identified fundamental bands are used for examination of the alternative assignments proposed in earlier studies. Potential energy distributions (PED) and overlaps of the in-plane normal modes with frequencies below 850 cm indicate that the correspondence of the respective vibrations of the deuterated and non-deuterated molecule is very good. A blue-shift of the 00 transition due to the isotopic substitution, is equal to 47 cm. This relatively large value is caused primarily by a significant decrease of the N-H stretching frequency associated with the increase of strength of the intramolecular hydrogen bond upon the electronic excitation. The deuteration shift of the 00 band was interpreted in terms of the differences of the zero point energy (ZPE) between the S 0 and S 1 electronic states, computed with DFT and TD-DFT methods, respectively.

  15. The use of deuterated ethyl acetate in highly concentrated electrolyte as a low-cost solvent for in situ neutron diffraction measurements of Li-ion battery electrodes

    International Nuclear Information System (INIS)

    Petibon, R.; Li, Jing; Sharma, Neeraj; Pang, Wei Kong; Peterson, Vanessa K.; Dahn, J.R.

    2015-01-01

    A low-cost deuterated electrolyte suitable for in situ neutron diffraction measurements of normal and high voltage Li-ion battery electrodes is reported here. Li[Ni 0.4 Mn 0.4 Co 0.2 ]O 2 /graphite (NMC(442)/graphite) pouch cells filled with 1:0.1:2 (molar ratio) of lithium bis(fluorosulfonyl) imide (LiFSi):LiPF 6 : ethyl acetate (EA) and LiFSi:LiPF 6 :deuterated EA (d8-EA) electrolytes were successfully cycled between 2.8 V and 4.7 V at 40°C for 250 h without significant capacity loss, polarization growth, or gas production. The signal-to-noise ratio of neutron powder diffraction patterns taken on NMC(442) powder with a conventional deuterated organic carbonate-based electrolyte and filled with LiFSi:LiPF 6 :d8-EA electrolyte were virtually identical. Out of all the solvents widely available in deuterated form tested in highly-concentrated systems, EA was the only one providing a good balance between cost and charge-discharge capacity retention to 4.7 V. The use of such an electrolyte blend would half the cost of deuterated solvents needed for in situ neutron diffraction measurements of Li-ion batteries compared to conventional deuterated carbonate-based electrolytes

  16. Using deuterated PAH amendments to validate chemical extraction methods to predict PAH bioavailability in soils

    International Nuclear Information System (INIS)

    Gomez-Eyles, Jose L.; Collins, Chris D.; Hodson, Mark E.

    2011-01-01

    Validating chemical methods to predict bioavailable fractions of polycyclic aromatic hydrocarbons (PAHs) by comparison with accumulation bioassays is problematic. Concentrations accumulated in soil organisms not only depend on the bioavailable fraction but also on contaminant properties. A historically contaminated soil was freshly spiked with deuterated PAHs (dPAHs). dPAHs have a similar fate to their respective undeuterated analogues, so chemical methods that give good indications of bioavailability should extract the fresh more readily available dPAHs and historic more recalcitrant PAHs in similar proportions to those in which they are accumulated in the tissues of test organisms. Cyclodextrin and butanol extractions predicted the bioavailable fraction for earthworms (Eisenia fetida) and plants (Lolium multiflorum) better than the exhaustive extraction. The PAHs accumulated by earthworms had a larger dPAH:PAH ratio than that predicted by chemical methods. The isotope ratio method described here provides an effective way of evaluating other chemical methods to predict bioavailability. - Research highlights: → Isotope ratios can be used to evaluate chemical methods to predict bioavailability. → Chemical methods predicted bioavailability better than exhaustive extractions. → Bioavailability to earthworms was still far from that predicted by chemical methods. - A novel method using isotope ratios to assess the ability of chemical methods to predict PAH bioavailability to soil biota.

  17. Pharmacokinetics of methadone during maintenance therapy: Pulse labeling with deuterated methadone in the steady state

    International Nuclear Information System (INIS)

    Aenggard, E.; Nilsson, M.I.; Holmstrand, J.; Gunne, L.M.; Uppsala Univ.; Karolinsky Institutet, Stockholm

    1979-01-01

    A technique is presented for study of steady state kinetics of methadone using pulse labeling with deuterated methadone (d 3 ) and mass fragmentography to measure both unlabeled and labeled methadone in blood. Seven subjects maintained on methadone for at least 10 months were admitted to a closed metabolic ward. The daily dose of unlabeled methadone (d 0 ) was substituted by one dose of methadone-d 3 and plasma levels of methadone-d 0 and methadone-d 3 were followed for 48 h using a precise (SD +- 5%) and sensitive (30 pmol/ml) mass fragmentographic technique. Plasma half-lives (tsub(1/2)) for both methadone-d 0 and methadone-d 3 were calculated from samples obtained 8-24 h following the dose of methadone-d 3 . The tsub(1/2) of oral methadone-d 3 was shorter (22 +- 2 h) than that of methadone-d 0 (52 +- 20 h). The same pattern was observed after intravenous administration. The results indicate multiple pools of methadone in the body. (orig.) 891 AJ/orig. 892 MKO [de

  18. High-excitation lines of deuterated formaldehyde (HDCO) in the Orion molecular cloud

    International Nuclear Information System (INIS)

    Loren, R.B.; Wootten, A.

    1985-01-01

    Five HDCO lines (up to 35 cm -1 ) have been detected in the narrow OMC-1 kinematic component. The best estimate of the [HDCO]/[H 2 CO] abundance ratio in OMC-1 is 0.01-0.03, at least an order of magnitude greater than the observed [DCO + ]/[HCO + ] abundance ratio. The [DCO + ]/[HCO + ] ratio greatly exceeds the [HDCO]/[H 2 CO] radio in cold clouds where the enhancement of both HDCO and DCO + abundances originates from H 2 D + . H 2 D + is abundant only at temperatures lower than found in OMC-1. The combination of a low [DCO + ]/[HCO + ] and high [HDCO]/[H 2 CO] abundance ratio in OMC-1 requires a different HDCO formation route at high temperature. This alternate HDCO formation path can occur because the exothermicity of the ion exchange reaction of HD and CH 3 + is greater than for the HD+H 3 + reaction. The CH 2 D + thus formed survives to higher temperatures than H 2 D + . Subsequent reactions with H 2 lead to CH 4 D + which by electronic recombination forms CH 2 D. The HDCO (H 2 CO) forms in the neutral-neutral reaction of CH 2 D (CH 3 ) and O. These reactions are not competitive in forming a variety of deuterated molecules at low temperatures since electronic recombination rapidly removes CH 2 D + and CH 4 D + ions while the abundant H 2 D + ion is slow to recombine, as reported by Smith and Adam in 1984

  19. Synthesis of specifically deuterated pregnanolone and pregnanediol sulphates for metabolic studies in pregant women

    International Nuclear Information System (INIS)

    Baillie, T.A.; Herz, J.E.; Anderson, R.A.; Sjovall, J.

    1975-01-01

    A series of specifically deuterated isomers of pregnanolone sulphate and pregnanediol mono- and disulphate have been synthesized for use in a study of the formation and metabolism of C 21 -steroid sulphates in the plasma of pregnant women. Hecogenin, the starting material for the synthesis, was equilibrated with NaO 2 H- 2 H 2 O and the resulting 11,11- 2 H 2 derivative converted directly to its tosylhydrazone. Reduction with sodium borohydride and degradation of the sapogenin side-chain gave 3β-hydroxy-5α-[11,11- 2 H 2 ] pregn-16-en-20-one (isotopic purity 91.6%). Further deuterium atoms were introduced in the 3α and 3α,20β positions by reductions with sodium borodeuteride and lithium aluminum deuteride, respectively. These reactions led to 3β-hydroxy-5α-[3α,11,11- 2 H 3 ] pregnan-20-one (isotopic purity 87.2%) and 5α-[3α,11,11,20β- 2 H 4 ] pregnane-3β,20α-diol (isotopic purity 83.9%). Steroids possessing the less readily accessible 3α-hydroxy-5α-[3β- 2 H] configuration were obtained, without loss of label, by epimerization of the 3β isomers. Pregnanolone sulphates and pregnanediol disulphates were prepared directly from the free alcohols, while the pregnanediol 3-monosulphates were synthesized from the appropriate pregnanediol 20-monoacetate derivatives

  20. Preparation and infrared spectra of differently deuterated tetramethyl-derivatives of the IV. main group

    International Nuclear Information System (INIS)

    Biedermann, S.

    1972-01-01

    19 different deuterated tetramethyl derivates of the type (CH 3 )sub(4-n)M(CH 3 )sub(n) of C, Si, Ge, Sn and Pb were prepared. Gas cuvettes with polyethylene, NaCl and KBr windows were used to absorb the infra-red spectra, the IR equipment Beckman IR 11 and IR 12 were used. The infra-red spectra of the above mentioned compounds were indicated from 33 to 4,000 cm -1 , the ground, upper and combination vibrations assigned, the PR separations of the partly well resolved rotation-vibration outlines determined and were compared with the calculated PR separations. The revision of the correlations performed by Graham for γsub(s)CH 3 and γsub(as)CH 3 in the race of vibration F 2 with Sn(CH 3 ) 4 and Pb(CH 3 ) 4 and the proposed one with C(CH 3 ) 4 , Si(CH 3 ) 4 and Ge(CH 3 ) 4 could be disproved by the new experimental results. (FW) [de

  1. Rotation and rotation-vibration spectroscopy of the 0+-0- inversion doublet in deuterated cyanamide.

    Science.gov (United States)

    Kisiel, Zbigniew; Kraśnicki, Adam; Jabs, Wolfgang; Herbst, Eric; Winnewisser, Brenda P; Winnewisser, Manfred

    2013-10-03

    The pure rotation spectrum of deuterated cyanamide was recorded at frequencies from 118 to 649 GHz, which was complemented by measurement of its high-resolution rotation-vibration spectrum at 8-350 cm(-1). For D2NCN the analysis revealed considerable perturbations between the lowest Ka rotational energy levels in the 0(+) and 0(-) substates of the lowest inversion doublet. The final data set for D2NCN exceeded 3000 measured transitions and was successfully fitted with a Hamiltonian accounting for the 0(+) ↔ 0(-) coupling. A smaller data set, consisting only of pure rotation and rotation-vibration lines observed with microwave techniques was obtained for HDNCN, and additional transitions of this type were also measured for H2NCN. The spectroscopic data for all three isotopic species were fitted with a unified, robust Hamiltonian allowing confident prediction of spectra well into the terahertz frequency region, which is of interest to contemporary radioastronomy. The isotopic dependence of the determined inversion splitting, ΔE = 16.4964789(8), 32.089173(3), and 49.567770(6) cm(-1), for D2NCN, HDNCN, and H2NCN, respectively, is found to be in good agreement with estimates from a simple reduced quartic-quadratic double minimum potential.

  2. Development of new synthetic routes to bile pigments and synthesis of deuterated porphyrins

    International Nuclear Information System (INIS)

    Shim, Y.K.

    1985-01-01

    New synthetic routes to pyrromethanones using hydrogen peroxide/pyridine upon alpha-free pyrromethanes and a synthesis of mesobiliverdin are described. The pyrromethanones were applied to the synthesis of mesobiliverdin using 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ) oxidation of mesourbilin, to give a high yield of the desired mesobiliverdin. New synthetic methodology to pyrrolinones using various oxidizing reagents were also described. Treatment of alpha-free pyrrole with thallium(III) trifluoroacetate (TTFA) gave a mixture of a pyrrolinone and a dimeric compound. The yield and the ratio of the two products were variable depending upon the solvents and the mole ratio of the TTFA used. Pyrrolinone syntheses using the other oxidizing reagents are also described. Syntheses of carbon-14 labelled biliverdins are also described. In addition, the preparation of biliverdin IX-BETA using b-bilene route is described. The second part of this study contains an introduction to porphyrins and syntheses of 6,7-bis(2-methoxycarbonyl-1,1-dideuteroethyl)-1,3,5,8-tetramethyl-2,4-divinylporphyrin. The latter is important in the study of heme protein reconstitution experiments. As a result of numerous synthetic approaches the desired product was obtained from the appropriately deuterated formylpyrrole using the a,c-biladiene route

  3. Using deuterated PAH amendments to validate chemical extraction methods to predict PAH bioavailability in soils

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Eyles, Jose L., E-mail: j.l.gomezeyles@reading.ac.uk [University of Reading, School of Human and Environmental Sciences, Soil Research Centre, Reading, RG6 6DW Berkshire (United Kingdom); Collins, Chris D.; Hodson, Mark E. [University of Reading, School of Human and Environmental Sciences, Soil Research Centre, Reading, RG6 6DW Berkshire (United Kingdom)

    2011-04-15

    Validating chemical methods to predict bioavailable fractions of polycyclic aromatic hydrocarbons (PAHs) by comparison with accumulation bioassays is problematic. Concentrations accumulated in soil organisms not only depend on the bioavailable fraction but also on contaminant properties. A historically contaminated soil was freshly spiked with deuterated PAHs (dPAHs). dPAHs have a similar fate to their respective undeuterated analogues, so chemical methods that give good indications of bioavailability should extract the fresh more readily available dPAHs and historic more recalcitrant PAHs in similar proportions to those in which they are accumulated in the tissues of test organisms. Cyclodextrin and butanol extractions predicted the bioavailable fraction for earthworms (Eisenia fetida) and plants (Lolium multiflorum) better than the exhaustive extraction. The PAHs accumulated by earthworms had a larger dPAH:PAH ratio than that predicted by chemical methods. The isotope ratio method described here provides an effective way of evaluating other chemical methods to predict bioavailability. - Research highlights: > Isotope ratios can be used to evaluate chemical methods to predict bioavailability. > Chemical methods predicted bioavailability better than exhaustive extractions. > Bioavailability to earthworms was still far from that predicted by chemical methods. - A novel method using isotope ratios to assess the ability of chemical methods to predict PAH bioavailability to soil biota.

  4. Retinal Biocompatibility of Brilliant Blue G with Deuterated Water for Chromovitrectomy

    Directory of Open Access Journals (Sweden)

    Emmerson Badaró

    2014-01-01

    Full Text Available Purpose: To investigate the retinal biocompatibility of Brilliant Blue G with deuterated water (BBG-D2O as a vital dye for chromovitrectomy. Methods: In this animal study, 0.05 mL of 0.25 g/L Brilliant Blue G (BBG associated with 0.13 mL/mL of deuterium oxide (D2O was injected intravitreally in the right eye and the same amount of balanced salt solution (BSS was injected similarly in the left eye of rabbits. Clinical examination and histology with light microscopy were performed after seven days. Retinal cell layers were evaluated for morphologic alterations. Electroretinographic (ERG changes were also assessed at baseline and 7 days after the injections. Results: A total of 6 rabbits were included in the study. The gross histopathologic appearance of the retina, choroid, sclera and optic nerve was within normal limits without any sign of severe retinal necrosis or cystic degeneration. Light microscopy showed that BBG-D2O caused no substantial alterations in retinal layers as compared to control eyes. The injection of BBG-D2O did not induce considerable functional ERG alterations. Conclusion: Intravitreal injection of BBG-D2O 0.25 g/L seems to induce no retinal toxicity as documented by lack of functional and histological changes.

  5. Gaseous emissions from biogas-digestate management and from fertilized soils. A study with special reference to nitrous oxide determination by stable isotope and isotopomer techniques

    Energy Technology Data Exchange (ETDEWEB)

    Koester, Jan Reent

    2014-07-02

    Biogas production from energy crops and organic residues for generating electricity is promoted in several European countries to reduce greenhouse gas (GHG) emissions from fossil fuels and thus to slow down global warming and climate change. However, significant GHG (in particular methane, CH{sub 4}, and nitrous oxide, N{sub 2}O) as well as ammonia (NH{sub 3}) emissions may occur from anaerobic digestates (AD), the residues of the biogas production process, during storage periods prior to land spreading as organic fertilizers, when these storage facilities are not covered. In the present study, Open Path FTIR as a non invasive remote sensing technique in combination with the micrometeorological bLS model was successfully evaluated upon its applicability at open AD lagoons, and emissions from two lagoons were determined in several trials. Emissions were found to be dominated by CH{sub 4} and NH{sub 3}, reducing the GHG savings of biogas energy considerably. During AD land spreading significant trace gas amounts can be emitted to the atmosphere, which are usually dominated by NH{sub 3}. During winter, these emissions are often considered to be low; however, in the present study it was shown that NH{sub 3} emissions under cold temperature conditions can be significant, especially when the soil is frozen and AD infiltration is hampered. AD applied to soil as organic fertilizer may increase N{sub 2}O emissions, which derive from biochemical N transformation processes. N{sub 2}O as well as N{sub 2} emissions after AD and cattle slurry application to soil have been investigated in an incubation study, indicating lower N{sub 2}O and N{sub 2} emissions via denitrification from AD treated soil due to its lower carbon content. N{sub 2}O source apportioning in such studies is crucial for improving process understanding and advancing mitigation strategies. The analysis of the different N{sub 2}O isotopomer species with particular focus on the intramolecular {sup 15}N

  6. Gaseous emissions from biogas-digestate management and from fertilized soils. A study with special reference to nitrous oxide determination by stable isotope and isotopomer techniques

    International Nuclear Information System (INIS)

    Koester, Jan Reent

    2014-01-01

    Biogas production from energy crops and organic residues for generating electricity is promoted in several European countries to reduce greenhouse gas (GHG) emissions from fossil fuels and thus to slow down global warming and climate change. However, significant GHG (in particular methane, CH_4, and nitrous oxide, N_2O) as well as ammonia (NH_3) emissions may occur from anaerobic digestates (AD), the residues of the biogas production process, during storage periods prior to land spreading as organic fertilizers, when these storage facilities are not covered. In the present study, Open Path FTIR as a non invasive remote sensing technique in combination with the micrometeorological bLS model was successfully evaluated upon its applicability at open AD lagoons, and emissions from two lagoons were determined in several trials. Emissions were found to be dominated by CH_4 and NH_3, reducing the GHG savings of biogas energy considerably. During AD land spreading significant trace gas amounts can be emitted to the atmosphere, which are usually dominated by NH_3. During winter, these emissions are often considered to be low; however, in the present study it was shown that NH_3 emissions under cold temperature conditions can be significant, especially when the soil is frozen and AD infiltration is hampered. AD applied to soil as organic fertilizer may increase N_2O emissions, which derive from biochemical N transformation processes. N_2O as well as N_2 emissions after AD and cattle slurry application to soil have been investigated in an incubation study, indicating lower N_2O and N_2 emissions via denitrification from AD treated soil due to its lower carbon content. N_2O source apportioning in such studies is crucial for improving process understanding and advancing mitigation strategies. The analysis of the different N_2O isotopomer species with particular focus on the intramolecular "1"5N distribution within the asymmetric N_2O molecules (the so called 'site preference

  7. THE HERSCHEL AND IRAM CHESS SPECTRAL SURVEYS OF THE PROTOSTELLAR SHOCK L1157-B1: FOSSIL DEUTERATION

    Energy Technology Data Exchange (ETDEWEB)

    Codella, C.; Fontani, F.; Vasta, M. [INAF, Osservatorio Astrofisico di Arcetri, Largo Enrico Fermi 5, I-50125 Firenze (Italy); Ceccarelli, C.; Lefloch, B.; Kahane, C.; Taquet, V.; Wiesenfeld, L. [UJF-Grenoble 1/CNRS-INSU, Institut de Planetologie et d' Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041 (France); Busquet, G. [INAF - Istituto di Astrofisica e Planetologia Spaziali, via Fosso del Cavaliere 100, I-00133, Roma (Italy); Caselli, P. [School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT (United Kingdom); Lis, D. [California Institute of Technology, Cahill Center for Astronomy and Astrophysics 301-17, Pasadena, CA 91125 (United States); Viti, S., E-mail: codella@rcetri.astro.it [Department of Physics and Astronomy, University College London, London (United Kingdom)

    2012-09-20

    We present the first study of deuteration toward the protostellar shock L1157-B1, based on spectral surveys performed with the Herschel-HIFI and IRAM 30 m telescopes. The L1157 outflow is driven by a low-mass Class 0 protostar and is considered the prototype of the so-called chemically active outflows. The young (2000 yr), bright blueshifted bow shock, B1, is an ideal laboratory for studying the gas chemically enriched by the release of dust mantles due to the passage of a shock. A total of 12 emission lines (up to E{sub u} = 63 K) of CH{sub 2}DOH, HDCO, and DCN are detected. In addition, two lines of NH{sub 2}D and HDO are tentatively reported. To estimate the deuteration, we also extracted from our spectral survey emission lines of non-deuterated isotopologues ({sup 13}CH{sub 3}OH, H{sub 2} {sup 13}CO, H{sup 13}CN, H{sub 2} {sup 13}CO, and NH{sub 3}). We infer higher deuteration fractions for CH{sub 3}OH (D/H = 0.2-2 Multiplication-Sign 10{sup -2}) and H{sub 2}CO (5-8 Multiplication-Sign 10{sup -3}) than for H{sub 2}O (0.4-2 Multiplication-Sign 10{sup -3}), HCN ({approx}10{sup -3}), and ammonia ({<=}3 Multiplication-Sign 10{sup -2}). The measurement of deuteration of water, formaldehyde, and methanol in L1157-B1 provides a fossil record of the gas before it was shocked by the jet driven by the protostar. A comparison with gas-grain models indicates that the gas passed through a low-density ({<=}10{sup 3} cm{sup -3}) phase, during which the bulk of water ices formed, followed by a phase of increasing density, up to 3 Multiplication-Sign 10{sup 4} cm{sup -3}, during which formaldehyde and methanol ices formed.

  8. The synthesis of the 14C and 2H-isotopomers of (R)-N-[2-(2'-ethoxyphenoxy)-ethyl]-N-2-[3-(4'-methoxy-3'-sulfonamido)-phenyl ]-propylamine hydrochloride, an α1-adrenoreceptor antagonist

    International Nuclear Information System (INIS)

    Wheeler, W.J.; Schmiegel, K.K.; Hunden, D.C.

    1989-01-01

    The synthesis of [ 14 C]- and [ 2 H]-labeled LY253351 (YM12617-1), a potent α 1 -receptor antagonist, which is potentially useful in the treatment of benign prostatic hypertrophy (BPH) is described. The [ 14 C]-isotopomer was synthesized from [ 14 C]-potassium cyanide in nine steps in 1.5% radiochemical yield. One of the key intermediates, [ 14 C]-4-methoxyphenylacetone, was synthesized from [ 14 C]-4-methoxyphenylacetyl chloride by a Pd(0)-catalyzed reaction with tetramethylstannane. The [ 2 H]-labeled material was synthesized by a Pd/C catalyzed reductive amination with deuterium gas. (author)

  9. Selective deuteration for molecular insights into the digestion of medium chain triglycerides.

    Science.gov (United States)

    Salentinig, Stefan; Yepuri, Nageshwar Rao; Hawley, Adrian; Boyd, Ben J; Gilbert, Elliot; Darwish, Tamim A

    2015-09-01

    Medium chain triglycerides (MCTs) are a unique form of dietary fat that have a wide range of health benefits. They are molecules with a glycerol backbone esterified with medium chain (6-12 carbon atoms) fatty acids on the two outer (sn-1 and sn-3) and the middle (sn-2) positions. During lipid digestion in the gastrointestinal tract, pancreatic lipase stereoselectively hydrolyses the ester bonds of these triglycerides on the sn-1 and sn-3 positions resulting in sn-2 monoglyceride and fatty acids as major products. However, the sn-2 monoglycerides are thermodynamically less stable than their sn-1/3 counterparts. Isomerization or fatty acid migration from the sn-2 monoglyceride to sn-1/3 monoglyceride may occur spontaneously and would lead to glycerol and fatty acid as final products. Here, tricaprin (C10) with selectively deuterated fatty acid chains was used for the first time to monitor chain migration and the stereoselectivity of the pancreatic lipase-catalyzed hydrolysis of ester bonds. The intermediate and final digestion products were studied using NMR and mass spectrometry under biologically relevant conditions. The hydrolysis of the sn-2 monocaprin to glycerol and capric acid did not occur within biologically relevant timescales and fatty acid migration occurs only in limited amounts as a result of the presence of undigested diglyceride species over long periods of time in the digestion medium. The slow kinetics for the exchange of the sn-2 fatty acid chain and the stereoselectivity of pancreatic lipase on MCTs is relevant for industrial processes that involve enzymatic interesterification and the production of high-value products such as specific structured triacylglycerols, confectionery fats and nutritional products. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Low-frequency ESR studies on permeable and impermeable deuterated nitroxyl radicals in corn oil solution.

    Science.gov (United States)

    David Jebaraj, D; Utsumi, Hideo; Milton Franklin Benial, A

    2018-04-01

    Low-frequency electron spin resonance studies were performed for 2 mM concentration of deuterated permeable and impermeable nitroxyl spin probes, 3-methoxycarbonyl-2,2,5,5-tetramethyl-pyrrolidine-1-oxyl and 3-carboxy-2,2,5,5,-tetramethyl-1-pyrrolidinyloxy in pure water and various concentrations of corn oil solution. The electron spin resonance parameters such as the line width, hyperfine coupling constant, g factor, rotational correlation time, permeability, and partition parameter were estimated. The broadening of line width was observed for nitroxyl radicals in corn oil mixture. The rotational correlation time increases with increasing concentration of corn oil, which indicates the less mobile nature of spin probe in corn oil mixture. The membrane permeability and partition parameter values were estimated as a function of corn oil concentration, which reveals that the nitroxyl radicals permeate equally into the aqueous phase and oil phase at the corn oil concentration of 50%. The electron spin resonance spectra demonstrate the permeable and impermeable nature of nitroxyl spin probes. From these results, the corn oil concentration was optimized as 50% for phantom studies. In this work, the corn oil and pure water mixture phantom models with various viscosities correspond to plasma membrane, and whole blood membrane with different hematocrit levels was studied for monitoring the biological characteristics and their interactions with permeable nitroxyl spin probe. These results will be useful for the development of electron spin resonance and Overhauser-enhanced magnetic resonance imaging modalities in biomedical applications. Copyright © 2017 John Wiley & Sons, Ltd.

  11. COSMOLOGICAL CONCORDANCE OR CHEMICAL COINCIDENCE? DEUTERATED MOLECULAR HYDROGEN ABUNDANCES AT HIGH REDSHIFT

    International Nuclear Information System (INIS)

    Tumlinson, J.; Malec, A. L.; Murphy, M. T.; Carswell, R. F.; Jorgenson, R. A.; Buning, R.; Ubachs, W.; Milutinovic, N.; Ellison, S. L.; Prochaska, J. X.; Wolfe, A. M.

    2010-01-01

    We report two detections of deuterated molecular hydrogen (HD) in QSO absorption-line systems at z>2. Toward J2123-0500, we find N(HD) =13.84 ± 0.2 for a sub-Damped Lyman Alpha system (DLA) with metallicity ≅0.5Z sun and N(H 2 ) = 17.64 ± 0.15 at z = 2.0594. Toward FJ0812+32, we find N(HD) =15.38 ± 0.3 for a solar-metallicity DLA with N(H 2 ) = 19.88 ± 0.2 at z = 2.6265. These systems have ratios of HD to H 2 above that observed in dense clouds within the Milky Way disk and apparently consistent with a simple conversion from the cosmological ratio of D/H. These ratios are not readily explained by any available model of HD chemistry, and there are no obvious trends with metallicity or molecular content. Taken together, these two systems and the two published z>2 HD-bearing DLAs indicate that HD is either less effectively dissociated or more efficiently produced in high-redshift interstellar gas, even at low molecular fraction and/or solar metallicity. It is puzzling that such diverse systems should show such consistent HD/H 2 ratios. Without clear knowledge of all the aspects of HD chemistry that may help determine the ratio HD/H 2 , we conclude that these systems are potentially more revealing of gas chemistry than of D/H itself and that it is premature to use such systems to constrain D/H at high redshift.

  12. Deuterated (d6)-dextromethorphan elicits antidepressant-like effects in mice.

    Science.gov (United States)

    Nguyen, Linda; Scandinaro, Anna L; Matsumoto, Rae R

    2017-10-01

    The over-the-counter antitussive dextromethorphan (DM) may have rapid antidepressant actions based on its overlapping pharmacology with ketamine, which has shown fast antidepressant effects but whose widespread use remains limited by problematic side effects. We have previously shown that DM produces antidepressant-like effects in the forced swim test (FST) and tail suspension test (TST) that are mediated in part through α-amino-3-hydroxy-5-methyl-4-isoxazole propionic (AMPA) and sigma-1 receptors, two protein targets associated with a faster onset of antidepressant efficacy. To utilize DM clinically, however, a major challenge that must be addressed is its rapid first-pass metabolism. Two strategies to inhibit metabolism of DM and maintain stable therapeutic blood levels are 1) chemically modifying DM and 2) adding quinidine, an inhibitor of the primary metabolizer of DM, the cytochrome P450 (CYP) 2D6 enzyme. The purpose of this study was to determine if modified DM (deuterated (d6)-DM) elicits antidepressant-like effects and if AMPA and sigma-1 receptors are involved. Furthermore, d6-DM was tested in conjunction with quinidine to determine if further slowing the metabolism of d6-DM affects its antidepressant-like actions. In the FST and TST, d6-DM produced antidepressant-like effects. Upon further investigation in the FST, the most validated animal model for predicting antidepressant efficacy, d6-DM produced antidepressant-like effects both in the absence and presence of quinidine. However, pretreatment with neither an AMPA receptor antagonist (NBQX) nor sigma-1 receptor antagonists (BD1063, BD1047) significantly attenuated the antidepressant-like effects. The data suggest d6-DM has antidepressant-like effects, though it may be recruiting different molecular targets and/or acting through a different mix or ratio of metabolites from regular DM. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Residue-specific membrane location of peptides and proteins using specifically and extensively deuterated lipids and {sup 13}C-{sup 2}H rotational-echo double-resonance solid-state NMR

    Energy Technology Data Exchange (ETDEWEB)

    Xie Li; Ghosh, Ujjayini; Schmick, Scott D.; Weliky, David P., E-mail: weliky@chemistry.msu.edu [Michigan State University, Department of Chemistry (United States)

    2013-01-15

    Residue-specific location of peptides in the hydrophobic core of membranes was examined using {sup 13}C-{sup 2}H REDOR and samples in which the lipids were selectively deuterated. The transmembrane topology of the KALP peptide was validated with this approach with substantial dephasing observed for deuteration in the bilayer center and reduced or no dephasing for deuteration closer to the headgroups. Insertion of {beta} sheet HIV and helical and {beta} sheet influenza virus fusion peptides into the hydrophobic core of the membrane was validated in samples with extensively deuterated lipids.

  14. Continuous-Flow Synthesis of Deuterium-Labeled Antidiabetic Chalcones: Studies towards the Selective Deuteration of the Alkynone Core

    Directory of Open Access Journals (Sweden)

    Sándor B. Ötvös

    2016-03-01

    Full Text Available Flow chemistry-based syntheses of deuterium-labeled analogs of important antidiabetic chalcones were achieved via highly controlled partial C≡C bond deuteration of the corresponding 1,3-diphenylalkynones. The benefits of a scalable continuous process in combination with on-demand electrolytic D2 gas generation were exploited to suppress undesired over-reactions and to maximize reaction rates simultaneously. The novel deuterium-containing chalcone derivatives may have interesting biological effects and improved metabolic properties as compared with the parent compounds.

  15. Reactions of tritium atoms with amino acids, deuterated amino acids and mixtures of amino acids. Additivity property and isotope effect

    International Nuclear Information System (INIS)

    Badun, G.A.; Filatov, Eh.S.

    1988-01-01

    Interaction of tritium atoms with glycine (1) and leucine (2) amino acids, deuterated amino acids, their mixtures and glycylleucine (3) peptide in the 77-300 K temperature range is studied in isothermal and gradient regimes. Tagged amino acids were separated from targets after conducting the reaction. At T 150 K are associated with intermolecular transmission of free valence in the mixture of amino acids. Regularities of the reaction found for the mixture of amino acids are conserved for (3) as well, i.e. the peptide bond does not essentially affect the reaction of isotopic exchange conditioned by atomic tritium

  16. The Deuterator: software for the determination of backbone amide deuterium levels from H/D exchange MS data

    Directory of Open Access Journals (Sweden)

    Tsinoremas NF

    2007-05-01

    Full Text Available Abstract Background The combination of mass spectrometry and solution phase amide hydrogen/deuterium exchange (H/D exchange experiments is an effective method for characterizing protein dynamics, and protein-protein or protein-ligand interactions. Despite methodological advancements and improvements in instrumentation and automation, data analysis and display remains a tedious process. The factors that contribute to this bottleneck are the large number of data points produced in a typical experiment, each requiring manual curation and validation, and then calculation of the level of backbone amide exchange. Tools have become available that address some of these issues, but lack sufficient integration, functionality, and accessibility required to address the needs of the H/D exchange community. To date there is no software for the analysis of H/D exchange data that comprehensively addresses these issues. Results We have developed an integrated software system for the automated analysis and representation of H/D exchange data that has been titled "The Deuterator". Novel approaches have been implemented that enable high throughput analysis, automated determination of deuterium incorporation, and deconvolution of overlapping peptides. This has been achieved by using methods involving iterative theoretical envelope fitting, and consideration of peak data within expected m/z ranges. Existing common file formats have been leveraged to allow compatibility with the output from the myriad of MS instrument platforms and peptide sequence database search engines. A web-based interface is used to integrate the components of The Deuterator that are able to analyze and present mass spectral data from instruments with varying resolving powers. The results, if necessary, can then be confirmed, adjusted, re-calculated and saved. Additional tools synchronize the curated calculation parameters with replicate time points, increasing throughput. Saved results can then

  17. Neutron and soft X-ray emission from wire array Z-pinch imploding onto deuterated fiber

    International Nuclear Information System (INIS)

    Klir, D.; Kravarik, J.; Kubes, P.

    2005-01-01

    The implosion of a wire array Z-pinch onto a deuterated fiber was studied. The peak power of soft X-rays exceeded 200 GW and the total emitted energy was 2-8 kJ. The radiation was close to the radiation of the blackbody with the temperature of 40 eV. The neutron yield from the D-D reaction reached 2x10 8 per shot. The mean energy of neutrons determined in the axial direction was shifted from 2.45 MeV towards higher energies [ru

  18. Hydrogen/deuterium exchange of cross-linkable alpha-amino acid derivatives in deuterated triflic acid

    OpenAIRE

    Wang, Lei; Murai, Yuta; Yoshida, Takuma; Okamoto, Masashi; Masuda, Katsuyoshi; Sakihama, Yasuko; Hashidoko, Yasuyuki; Hatanaka, Yasumaru; Hashimoto, Makoto

    2014-01-01

    In this paper we report here a hydrogen/deuterium exchange (H/D exchange) of cross-linkable alpha-amino acid derivatives with deuterated trifluoromethanesulfonic acid (TfOD). H/D exchange with TfOD was easily applied to o-catechol containing phenylalanine (DOPA) within an hour. A partial H/D exchange was observed for trifluoromethyldiazirinyl (TFMD) phenylalanine derivatives. N-Acetyl-protected natural aromatic alpha-amino acids (Tyr and Trp) were more effective in H/D exchange than unprotect...

  19. Measurement of the response of the deuterated scintillators NE 232 and NE 230 to protons and deuterons

    International Nuclear Information System (INIS)

    Tornow, W.; Arnold, W.; Herdtweck, J.; Mertens, G.

    1986-01-01

    The response of the deuterated scintillators NE 232 and NE 230 to protons and deuterons has been measured via elastic neutron-proton and neutron-deuteron scattering using the two mixtures of C 6 H 12 /C 6 D 12 and C 6 H 6 /C 6 D 6 and ''pure'' scintillators. The energy range covered for protons and deuterons was about 1-16 MeV. The light output relation Lsub(p)(E)=(1/2)Lsub(d) (2E) has been observed. (orig.)

  20. Raman spectra of ordinary and deuterated liquid ammonias; Spectres Raman des ammoniacs ordinaire et deuteries liquides

    Energy Technology Data Exchange (ETDEWEB)

    Ceccaldi, M; Leicknam, J P [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires, direction des materiaux et des combustibles nucleaires, departement de physico-chimie, service des isotopes stables, service de spectrometrie de masse

    1968-12-01

    The three deuterated ammonia molecules, as well as ordinary ammonia, have been examined in the liquid state by Raman spectroscopy using a high-pressure cell described elsewhere. This work thus completes the infrared spectrometry studies. We have examined the NH and ND valency absorption regions. The polarization measurements and isotope effect considerations make it possible to confirm most of the attributions recently proposed for interpreting the infrared spectra of the four isotopic molecules: the apparent disagreement between the NH{sub 3} and ND{sub 3} spectra obtained in this region by infrared and Raman spectroscopy is discussed: by the first technique the number of bands in the spectra corresponds well to the theoretically expected number, and the relative intensities conform more or less to expectations; the Raman spectra however have a strong supplementary band in the same region, produced by a Fermi resonance; it is possible to explain, from theoretical considerations, why this resonance appears so easily in the Raman spectrum, whereas it is detected in the infrared only by a very detailed analysis of the effects of solvents on the ammonia. (authors) [French] Les trois ammoniacs deuteries, ainsi que l'ammoniac ordinaire, sont examines a l'etat liquide par spectrometrie Raman, a l'aide d'une cuve haute pression decrite par ailleurs. Ce travail complete donc les etudes effectuees par spectrometrie infra-rouge. Nous avons examine les regions d'absorption de valence NH et ND. Les mesures de polarisation et des considerations sur les effets isotopiques permettent de confirmer la plupart des attributions proposees recemment pour interpreter les spectres infra-rouges des quatre molecules isotopiques: on discute egalement l'apparent desaccord entre les spectres de NH{sub 3} et de ND{sub 3} obtenus dans cette region par infra-rouge et Raman: par la premiere technique le nombre de bandes relevees sur les spectres correspond bien au nombre theoriquement attendu et

  1. Estimation of nitrogenase activity in the presence of ethylene biosynthesis by use of deuterated acetylene as a substrate

    International Nuclear Information System (INIS)

    Lin-Vien, D.; Fateley, W.G.; Davis, L.C.

    1989-01-01

    Nitrogenase reduces deuterated acetylene primarily to cis dideuterated ethylene. This can be distinguished from undeuterated ethylene by the use of Fourier transform infrared spectroscopy. Characteristic bands in the region from 800 to 3,500 cm-1 can be used to identify and quantitate levels of these products. This technique is applicable to field studies of nitrogen fixation where ethylene biosynthesis by plants or bacteria is occurring. We have verified the reaction stoichiometry by using Klebsiella pneumoniae and Bradyrhizobium japonicum in soybeans. The most useful bands for quantitation of substrate purity and product distribution are as follows: acetylene-d0, 3,374 cm-1; acetylene-d1, 2,584 cm-1; acetylene-d2, 2,439 cm-1; cis-ethylene-d2, 843 cm-1; trans-ethylene-d2, 988 cm-1; ethylene-d1, 943 cm-1; ethylene-d0, 949 cm-1. (The various deuterated ethylenes and acetylenes are designated by a lowercase d and subscript to indicate the number, but not the position, of deuterium atoms in the molecule.) Mass spectrometry coupled to a gas chromatograph system has been used to assist in quantitation of the substrate and product distributions. Significant amounts of trans-ethylene-d2 were produced by both wild-type and nifV mutant K. pneumoniae. Less of this product was observed with the soybean system

  2. Crystal Structure of the Sodium Cobaltate Deuterate Superconductor NaxCoO2o4xD2O (x=1/3)

    OpenAIRE

    Jorgensen, J. D.; Avdeev, M.; Hinks, D. G.; Burley, J. C.; Short, S.

    2003-01-01

    Neutron and x-ray powder diffraction have been used to investigate the crystal structures of a sample of the newly-discovered superconducting sodium cobaltate deuterate compound with composition Na0.31(3)CoO2o1.25(2)D2O and its anhydrous parent compound Na0.61(1)CoO2. The deuterate superconducting compound is formed by coordinating four D2O molecules (two above and two below) to each Na ion in a way that gives Na-O distances nearly equal to those in the parent compound. One deuteron of the D2...

  3. Neutron total cross-section of hydrogenous and deuterated 1- and 2-propanol and n-butanol measured using the VESUVIO spectrometer

    Science.gov (United States)

    Rodríguez Palomino, L. A.; Dawidowski, J.; Márquez Damián, J. I.; Cuello, G. J.; Romanelli, G.; Krzystyniak, M.

    2017-10-01

    This work presents the total cross sections of a set of normal and deuterated alcohols (hydrogenous 1- and 2-propanol and n-butanol, 1-propanol(OD) and fully deuterated 2-propanol and n-butanol), measured at spectrometer VESUVIO (ISIS spallation neutron source, United Kingdom). Granada's Synthetic Model was applied to describe those systems and a satisfactory agreement with the measured total cross section was achieved in the range of energies from 10-3 to 100 eV. The input parameters of the model were determined from the essential features of the vibrational spectra of the atoms that compose the systems, which were studied using Molecular Dynamics.

  4. Syntheses of deuterated leu-enkephalins and their use as internal standards for the quantification of leu-enkephalin by fast atom bombardment mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Benfenati, E. (Istituto di Ricerche Farmacologiche Mario Negri, Bergamo (Italy) Istituto di Ricerche Farmacologiche Mario Negri, Milan (Italy)); Icardi, G.; Chen, S. (Istituto di Ricerche Farmacologiche Mario Negri, Bergamo (Italy)); Fanelli, R. (Istituto di Ricerche Farmacologiche Mario Negri, Milan (Italy))

    1990-04-01

    We have developed a synthetic method for the preparation of di- and pentadeuterated leu-enkephalin (LE), Tyr-Gly-Gly-Phe-Leu, by proton-deuterium exchange using CF[sub 3]COOO[sup 2]H. Four to six deuterium atoms are introduced using a reaction temperature of 120[sup o]C and if 5% of [sup 2]H[sub 2]O is added the di-deuterated LE is obtained. These deuterated compounds are used as internal standards to plot calibration curves of LE using fast atom bombardment mass spectrometry. (author).

  5. Evidence of quantum correlations in the H/D-transfer dynamics in the hydrogen bonds in partially deuterated benzoic acid crystals

    Science.gov (United States)

    Takeda, Sadamu; Tsuzumitani, Akihiko; Chatzidimitriou-Dreismann, C. A.

    1992-10-01

    A precise investigation of spin—lattice relaxation rates for protons and deuterons of partially deuterated benzoic acid crystals showed a remarkable quenching of the transfer rate of an HD pair in hydrogen-bonded dimeric units of carboxyl groups with increasing concentration of D in the surrounding hydrogen bonds. A similar effect was also observed for partially deuterated crystals of acetylenedicarboxylic acid. This finding supports recent theoretical predictions of thermally activated protonic quantum correlation in condensed matter and proposes a new mechanism for the proton transfer in hydrogen bonds in condensed matter.

  6. Effect of hydrostatic pressure on the antiferroelectric phase transitions in ammonium dihydrogen arsenate NH4H2AsO4 and deuterated analogue

    International Nuclear Information System (INIS)

    Gesi, Kazuo; Ozawa, Kunio

    1984-01-01

    Effect of hydrostatic pressure on the antiferroelectric phase transitions in NH 4 H 2 AsO 4 and deuterated analogue (deuterium concentration --80%) was studied by dielectric constant measurements at high pressures up to about 0.8GPa. The transition temperature linearly decreases with increasing pressure with the ratios of -19.7K GPa -1 and -14.5K GPa -1 for NH 4 H 2 AsO 4 and the deuterated compound, respectively. The pressure effect is compared with previously reported results of other KH 2 PO 4 -type ferro- and antiferroelectric crystals. (author)

  7. Quantitative imaging of water flow in soil and roots using neutron radiography and deuterated water

    Energy Technology Data Exchange (ETDEWEB)

    Zarebanadkouki, Mohsen

    2013-05-08

    Where and how fast do roots take up water? Despite its importance in plant and soil sciences, there is limited experimental information on the location of water uptake along the roots of transpiring plants growing in soil. The answer to this question requires direct and in-situ measurement of the local flow of water into the roots. The aim of this study was to develop and apply a new method to quantify the local fluxes of water into different segments of the roots of intact plants. To this end, neutron radiography was used to trace the transport of deuterated water (D{sub 2}O) into the roots of lupines. Lupines were grown in aluminum containers filled with sandy soil. The soil was partitioned into different compartments using 1 cm-thick layers of coarse sand as capillary barriers. These barriers limited the diffusion of D{sub 2}O within the soil compartments. D{sub 2}O was locally injected into the selected soil compartments during the day (transpiring plants) and night (non-transpiring plants). Transport of D{sub 2}O into roots was then monitored by neutron radiography with spatial resolution of 100 μm and time intervals of 10 seconds. Neutron radiographs showed that: i) transport of D{sub 2}O into roots was faster during the day than during the night; 2) D{sub 2}O quickly moved along the roots towards the shoots during the day, while at night this axial transport was negligible. The differences between day and night measurements were explained by convective transport of D{sub 2}O into the roots. To quantify the net flow of water into roots, a simple convection-diffusion model was developed, where the increase rate of D{sub 2}O concentration in roots depended on the convective transport (net root water uptake) and the diffusion of D{sub 2}O into roots. The results showed that water uptake was not uniform along the roots. Water uptake was higher in the upper soil layers than in the deeper ones. Along an individual roots, the water uptake rate was higher in the

  8. Nano-scale bubble thermonuclear fusion in acoustically cavitated deuterated liquid

    International Nuclear Information System (INIS)

    Robert I Nigmatulin; Richard T Lahey Jr; Rusi Taleyarkhan

    2005-01-01

    Full text of publication follows: It has been experimentally shown (Taleyarkhan, West, Cho, Lahey, Nigmatulin, Block, 2002, 2004) that neutron emission and tritium formation may occur in deuterated acetone (D-acetone C 3 DO 6 ) under acoustic cavitation conditions. Intensity of the fast neutron (2.45 MeV) emission and tritium nucleus production is ∼ 4 x 10 5 s -1 . This suggests ultrahigh compression of matter produced inside bubbles during their collapse. In the paper a systematic theoretical analysis of the vapor bubble growth and subsequent implosion in intense acoustic fields in D-acetone is presented. The goal is to describe and explain the experimental observations of thermonuclear fusion for collapsing cavitation bubble in D-acetone. The dynamics of bubbles formed during maximum rarefaction in the liquid is numerically studied on the basis of the developed models of a single bubble and bubble clusters. It is supposed that during their growth the bubbles coagulate and form a few bigger bubbles, which then collapse under the action of additional pressure pulses produced in the liquid through the intensification of acoustic waves within the cluster. A shock wave is shown to be formed inside the bubble during the latter's rapid contraction. Focusing of this shock wave in the bubble center initiates dissociation and ionization, violent increases in density (10 4 kg m 3 ), pressure (10 10 -10 11 bar) and temperature (2 x 10 8 K), high enough to produce nuclear fusion reactions. The bubble looks like micro-hydrogen bomb. The diameter of the neutron emission zone is about 100 nm. The highest neutron emission is recorded at about 10-20 nm from the bubble center. It is found out that the intensity of bubble implosion and the number of neutron emitted increase with variations in nucleation phase, positive half-wave amplitude, liquid temperature and also with the involvement of coagulation mechanisms within the cluster during the bubble simultaneous growth. The number

  9. Quantitative imaging of water flow in soil and roots using neutron radiography and deuterated water

    International Nuclear Information System (INIS)

    Zarebanadkouki, Mohsen

    2013-01-01

    Where and how fast do roots take up water? Despite its importance in plant and soil sciences, there is limited experimental information on the location of water uptake along the roots of transpiring plants growing in soil. The answer to this question requires direct and in-situ measurement of the local flow of water into the roots. The aim of this study was to develop and apply a new method to quantify the local fluxes of water into different segments of the roots of intact plants. To this end, neutron radiography was used to trace the transport of deuterated water (D 2 O) into the roots of lupines. Lupines were grown in aluminum containers filled with sandy soil. The soil was partitioned into different compartments using 1 cm-thick layers of coarse sand as capillary barriers. These barriers limited the diffusion of D 2 O within the soil compartments. D 2 O was locally injected into the selected soil compartments during the day (transpiring plants) and night (non-transpiring plants). Transport of D 2 O into roots was then monitored by neutron radiography with spatial resolution of 100 μm and time intervals of 10 seconds. Neutron radiographs showed that: i) transport of D 2 O into roots was faster during the day than during the night; 2) D 2 O quickly moved along the roots towards the shoots during the day, while at night this axial transport was negligible. The differences between day and night measurements were explained by convective transport of D 2 O into the roots. To quantify the net flow of water into roots, a simple convection-diffusion model was developed, where the increase rate of D 2 O concentration in roots depended on the convective transport (net root water uptake) and the diffusion of D 2 O into roots. The results showed that water uptake was not uniform along the roots. Water uptake was higher in the upper soil layers than in the deeper ones. Along an individual roots, the water uptake rate was higher in the proximal segments than in the distal

  10. Hydrogen exchange during cell-free incorporation of deuterated amino acids and an approach to its inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Tonelli, Marco; Singarapu, Kiran K. [University of Wisconsin-Madison, National Magnetic Resonance Facility at Madison (NMRFAM), Department of Biochemistry (United States); Makino, Shin-ichi; Sahu, Sarata C.; Matsubara, Yuko [University of Wisconsin-Madison, Center for Eukaryotic Structural Genomics (CESG), Department of Biochemistry (United States); Endo, Yaeta [Ehime University, Cell-Free Science and Technology Research Center (Japan); Kainosho, Masatsune [Tokyo Metropolitan University, Center for Priority Areas (Japan); Markley, John L., E-mail: markley@nmrfam.wisc.edu [University of Wisconsin-Madison, National Magnetic Resonance Facility at Madison (NMRFAM), Department of Biochemistry (United States)

    2011-12-15

    Perdeuteration, selective deuteration, and stereo array isotope labeling (SAIL) are valuable strategies for NMR studies of larger proteins and membrane proteins. To minimize scrambling of the label, it is best to use cell-free methods to prepare selectively labeled proteins. However, when proteins are prepared from deuterated amino acids by cell-free translation in H{sub 2}O, exchange reactions can lead to contamination of {sup 2}H sites by {sup 1}H from the solvent. Examination of a sample of SAIL-chlorella ubiquitin prepared by Escherichia coli cell-free synthesis revealed that exchange had occurred at several residues (mainly at Gly, Ala, Asp, Asn, Glu, and Gln). We present results from a study aimed at identifying the exchanging sites and level of exchange and at testing a strategy for minimizing {sup 1}H contamination during wheat germ cell-free translation of proteins produced from deuterated amino acids by adding known inhibitors of transaminases (1 mM aminooxyacetic acid) and glutamate synthetase (0.1 mM l-methionine sulfoximine). By using a wheat germ cell-free expression system, we produced [U-{sup 2}H, {sup 15}N]-chlorella ubiquitin without and with added inhibitors, and [U-{sup 15}N]-chlorella ubiquitin as a reference to determine the extent of deuterium incorporation. We also prepared a sample of [U-{sup 13}C, {sup 15}N]-chlorella ubiquitin, for use in assigning the sites of exchange. The added inhibitors did not reduce the protein yield and were successful in blocking hydrogen exchange at C{sup {alpha}} sites, with the exception of Gly, and at C{sup {beta}} sites of Ala. We discovered, in addition, that partial exchange occurred with or without the inhibitors at certain side-chain methyl and methylene groups: Asn-H{sup {beta}}, Asp-H{sup {beta}}, Gln-H{sup {gamma}}, Glu-H{sup {gamma}}, and Lys-H{sup {epsilon}}. The side-chain labeling pattern, in particular the mixed chiral labeling resulting from partial exchange at certain sites, should be of

  11. Three-dimensional cooling pattern of a granitic pluton 2. The study of deuteric sub-solidus reactions in the Toki granite, Central Japan

    International Nuclear Information System (INIS)

    Yuguchi, Takashi; Tsuruta, Tadahiko; Nishiyama, Tadao

    2011-01-01

    Petrographical studies examining the development and variations of sub-solidus reactions recorded in the Toki granite represent the three-dimensional cooling pattern of this zoned pluton in Central Japan. Samples collected from 19 boreholes in the Toki granite show characteristics indicative of spatial variations in the extent of the sub-solidus reactions. Exsolution coarsening has produced microperthite, including albite-rich lamellae, in this pluton, while deuteric coarsening has resulted in the formation of patchperthite, myrmekite, and the reaction rim. The extent of the deuteric coarsening reactions can be evaluated from the width and spacing of the albite-rich patch in patchperthite and from the thickness of myrmekite and the reaction rim. The width, spacing, and thickness of these textural features increase systematically with elevation; they also increase gradually in the horizontal inward direction in the western part of the pluton but not in the eastern part of the pluton. The systematic variations in textural development indicate that the Toki granite cooled effectively from the roof and from the western margin during the deuteric coarsening stage. The deuteric coarsening may have occurred at temperatures below 500°C, as indicated by ternary feldspar thermometry. (author)

  12. Straightforward synthesis of 2,2,4,4,5,7,7-d{sub 7}-cholestane: a new deuterated standard in petroleum analysis

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Maicon Guerra de; Albert, Andre Luis Mazzei; Cardoso, Jari Nobrega; Lopes, Rosangela Sabbatini Capella; Lopes, Claudio Cerqueira, E-mail: maicon_iq@yahoo.com [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Inst. de Quimica

    2013-10-01

    A short and efficient synthesis of heptadeuterated 2,2,4,4,5,7,7-d7-cholestane (1) from cholesterol (3) is described. The deuterated material will be useful for the analysis of different sources of petroleum in analytical geochemistry laboratories as internal standard for quantification of steranes via gas chromatography-mass spectrometry (GC-MS). (author)

  13. Preparation of deuterated heterocyclic five-membered ring compounds (furan, thiophene, pyrrole, and derivatives) by base-catalyzed hydrogen isotope exchange with deuterium oxide

    International Nuclear Information System (INIS)

    Heinrich, K.H.; Herrmann, M.; Moebius, G.; Sprinz, H.

    1984-01-01

    Several deuterated heterocyclic compounds of the type of furan,thiophene and pyrrole were prepared by base-catalyzed proton exchange with deuterium oxide at temperatures above 423 K in a closed system. The determination of deuterium and its distribution within the molecules was carried out by mass spectrometry and 1 H nmr spectrometry. (author)

  14. Synthesis of 3 alpha-deuterated 7 alpha-hydroxy-DHEA and 7-oxo-DHEA and application in LC-MS/MS plasma analysis

    Czech Academy of Sciences Publication Activity Database

    Sosvorova, L.K.; Sarek, J.; Vitku, J.; Kvasnica, Miroslav

    2016-01-01

    Roč. 112, AUG (2016), s. 88-94 ISSN 0039-128X Institutional support: RVO:61389030 Keywords : 7 alpha-Hydroxy-DHEA * 7-Oxo-DHEA * Deuterated standard Subject RIV: CE - Biochemistry Impact factor: 2.282, year: 2016

  15. ALLocator: an interactive web platform for the analysis of metabolomic LC-ESI-MS datasets, enabling semi-automated, user-revised compound annotation and mass isotopomer ratio analysis.

    Science.gov (United States)

    Kessler, Nikolas; Walter, Frederik; Persicke, Marcus; Albaum, Stefan P; Kalinowski, Jörn; Goesmann, Alexander; Niehaus, Karsten; Nattkemper, Tim W

    2014-01-01

    Adduct formation, fragmentation events and matrix effects impose special challenges to the identification and quantitation of metabolites in LC-ESI-MS datasets. An important step in compound identification is the deconvolution of mass signals. During this processing step, peaks representing adducts, fragments, and isotopologues of the same analyte are allocated to a distinct group, in order to separate peaks from coeluting compounds. From these peak groups, neutral masses and pseudo spectra are derived and used for metabolite identification via mass decomposition and database matching. Quantitation of metabolites is hampered by matrix effects and nonlinear responses in LC-ESI-MS measurements. A common approach to correct for these effects is the addition of a U-13C-labeled internal standard and the calculation of mass isotopomer ratios for each metabolite. Here we present a new web-platform for the analysis of LC-ESI-MS experiments. ALLocator covers the workflow from raw data processing to metabolite identification and mass isotopomer ratio analysis. The integrated processing pipeline for spectra deconvolution "ALLocatorSD" generates pseudo spectra and automatically identifies peaks emerging from the U-13C-labeled internal standard. Information from the latter improves mass decomposition and annotation of neutral losses. ALLocator provides an interactive and dynamic interface to explore and enhance the results in depth. Pseudo spectra of identified metabolites can be stored in user- and method-specific reference lists that can be applied on succeeding datasets. The potential of the software is exemplified in an experiment, in which abundance fold-changes of metabolites of the l-arginine biosynthesis in C. glutamicum type strain ATCC 13032 and l-arginine producing strain ATCC 21831 are compared. Furthermore, the capability for detection and annotation of uncommon large neutral losses is shown by the identification of (γ-)glutamyl dipeptides in the same strains

  16. ALLocator: an interactive web platform for the analysis of metabolomic LC-ESI-MS datasets, enabling semi-automated, user-revised compound annotation and mass isotopomer ratio analysis.

    Directory of Open Access Journals (Sweden)

    Nikolas Kessler

    Full Text Available Adduct formation, fragmentation events and matrix effects impose special challenges to the identification and quantitation of metabolites in LC-ESI-MS datasets. An important step in compound identification is the deconvolution of mass signals. During this processing step, peaks representing adducts, fragments, and isotopologues of the same analyte are allocated to a distinct group, in order to separate peaks from coeluting compounds. From these peak groups, neutral masses and pseudo spectra are derived and used for metabolite identification via mass decomposition and database matching. Quantitation of metabolites is hampered by matrix effects and nonlinear responses in LC-ESI-MS measurements. A common approach to correct for these effects is the addition of a U-13C-labeled internal standard and the calculation of mass isotopomer ratios for each metabolite. Here we present a new web-platform for the analysis of LC-ESI-MS experiments. ALLocator covers the workflow from raw data processing to metabolite identification and mass isotopomer ratio analysis. The integrated processing pipeline for spectra deconvolution "ALLocatorSD" generates pseudo spectra and automatically identifies peaks emerging from the U-13C-labeled internal standard. Information from the latter improves mass decomposition and annotation of neutral losses. ALLocator provides an interactive and dynamic interface to explore and enhance the results in depth. Pseudo spectra of identified metabolites can be stored in user- and method-specific reference lists that can be applied on succeeding datasets. The potential of the software is exemplified in an experiment, in which abundance fold-changes of metabolites of the l-arginine biosynthesis in C. glutamicum type strain ATCC 13032 and l-arginine producing strain ATCC 21831 are compared. Furthermore, the capability for detection and annotation of uncommon large neutral losses is shown by the identification of (γ-glutamyl dipeptides in

  17. Stereoselective quantification of methadone and a d(6)-labeled isotopomer using high performance liquid chromatography-atmospheric pressure chemical ionization mass-spectrometry: application to a pharmacokinetic study in a methadone maintained subject.

    Science.gov (United States)

    Foster, David J R; Morton, Erin B; Heinkele, Georg; Mürdter, Thomas E; Somogyi, Andrew A

    2006-08-01

    There is evidence that the apparent oral clearance of rac-methadone is induced during the early phase of methadone maintenance treatment. However, it is not known if this is due to changes in bioavailability or if this phenomenon is stereoselective. This knowledge can be obtained by administering a dose of stable-labeled methadone at selected times during ongoing treatment. Therefore, the authors developed a stereoselective high performance liquid chromatography-atmospheric pressure chemical ionization mass-spectrometry assay for the quantification of the enantiomers of methadone and a d(6)-labeled isotopomer. The compounds were quantified in a single assay after liquid-liquid extraction and stereoselective high performance liquid chromatograph with atmospheric pressure chemical ionization-mass spectrometry detection. The following ions were monitored: m/z 310.15 for unlabeled methadone; m/z 316.15 for methadone-d(6); and m/z 313.15 for the methadone-d(3) (internal standard). Calibration curves ranged from 0.5 to 75 ng/mL for each compound. Extraction recovery was approximately 80% for all analytes, without evidence of differences between the unlabeled and stable-labeled compounds or concentration dependency. Minor ion promotion was observed (d(3)-labeled internal standard, with peak area ratios in extracted samples identical to control injections. The isotopomers did not alter each others' ionisation, even at 10:1 concentration ratios, and 10-fold diluted samples were within 10% of the nominal concentration. Assay performance was acceptable, with interassay and intra-assay bias and precision d(6) in a patient receiving chronic oral methadone maintenance therapy.

  18. A neutron powder diffraction study of deuterated α-resorcinol: a test of profile refinement using TLS constraints

    International Nuclear Information System (INIS)

    Bacon, G.E.; Lisher, E.J.

    1979-01-01

    Constrained TL, TLX and TLS refinements have been used, with the powder-profile method, in the analysis of accurate neutron powder data for deuterated α-resorcinol at room temperature. There is good agreement between the translational and librational parameters derived from the TL refinement and those obtained from an equivalent analysis of accurate single-crystal neutron measurements. The fine details of the benzene ring are lost in the powder analysis, but the molecular orientation and the OH bond angles are in good agreement with the single-crystal values. No significant improvement could be found in the powder fit by applying the full TLS theory and, therefore, the approximate TLX model appears to be adequate for powder data. (Auth.)

  19. Systematic study of (d,n) reactions at Ed = 16 MeV using a deuterated scintillator array

    International Nuclear Information System (INIS)

    Febbraro, M.; Becchetti, F.D.; Torres-Isea, R.O.; Riggins, A.; Lawrence, C.; Howard, A.M.; Kolata, J.J.

    2014-01-01

    We have developed a multi-element deuterated liquid scintillator array for the study of reactions involving neutrons utilizing high-speed digital signal processing. The liquid organic scintillators exhibit good digital pulse shape discrimination (DPSD). Typical configuration involves the detectors fixed to adjustable aluminium mounts, secured to an 80/20 aluminium frame. This allows for quick and adaptable configurations to be made for varying experimental conditions including measurements over a large angular range. A systematic study of (d,n) reactions at E d = 16 MeV on 9 Be, 11 B, 13 C, 14 N, 15 N, and 19 F has been conducted from 10 to 160 degrees (lab). In addition to previously unmeasured back-angle cross sections, this data can complement existing and future ( 3 He,d) measurements as an analog to (p,γ) for astrophysics applications

  20. Ion acceleration and D-D nuclear fusion in laser-generated plasma from advanced deuterated polyethylene.

    Science.gov (United States)

    Torrisi, Lorenzo

    2014-10-23

    Deuterated polyethylene targets have been irradiated by means of a 1016 W/cm2 laser using 600 J pulse energy, 1315 nm wavelength, 300 ps pulse duration and 70 micron spot diameter. The plasma parameters were measured using on-line diagnostics based on ion collectors, SiC detectors and plastic scintillators, all employed in time-of-flight configuration. In addition, a Thomson parabola spectrometer, an X-ray streak camera, and calibrated neutron dosimeter bubble detectors were employed. Characteristic protons and neutrons at maximum energies of 3.0 MeV and 2.45 MeV, respectively, were detected, confirming that energy spectra of reaction products coming from deuterium-deuterium nuclear fusion occur. In thick advanced targets a fusion rate of the order of 2 × 108 fusions per laser shot was calculated.

  1. The rate of lactate production from glucose in hearts is not altered by per-deuteration of glucose

    Science.gov (United States)

    Funk, Alexander M.; Anderson, Brian L.; Wen, Xiaodong; Hever, Thomas; Khemtong, Chalermchai; Kovacs, Zoltan; Sherry, A. Dean; Malloy, Craig R.

    2017-11-01

    This study was designed to determine whether perdeuterated glucose experiences a kinetic isotope effect (KIE) as glucose passes through glycolysis and is further oxidized in the tricarboxylic acid (TCA) cycle. Metabolism of deuterated glucose was investigated in two groups of perfused rat hearts. The control group was supplied with a 1:1 mixture of [U-13C6]glucose and [1,6-13C2]glucose, while the experimental group received [U-13C6,U-2H7]glucose and [1,6-13C2]glucose. Tissue extracts were analyzed by 1H, 2H and proton-decoupled 13C NMR spectroscopy. Extensive 2H-13C scalar coupling plus chemical shift isotope effects were observed in the proton-decoupled 13C NMR spectra of lactate, alanine and glutamate. A small but measureable (∼8%) difference in the rate of conversion of [U-13C6]glucose vs. [1,6-13C2]glucose to lactate, likely reflecting rates of Csbnd C bond breakage in the aldolase reaction, but conversion of [U-13C6]glucose versus [U-13C6,U-2H7]glucose to lactate did not differ. This shows that the presence of deuterium in glucose does not alter glycolytic flux. However, there were two distinct effects of deuteration on metabolism of glucose to alanine and oxidation of glucose in the TCA. First, alanine undergoes extensive exchange of methyl deuterons with solvent protons in the alanine amino transferase reaction. Second, there is a substantial kinetic isotope effect in metabolism of [U-13C6,U-2H7]glucose to alanine and glutamate. In the presence of [U-13C6,U-2H7]glucose, alanine and lactate are not in rapid exchange with the same pool of pyruvate. These studies indicate that the appearance of hyperpolarized 13C-lactate from hyperpolarized [U-13C6,U-2H7]glucose is not substantially influenced by a deuterium kinetic isotope effect.

  2. Effect of Isotopic Substitution on Elementary Processes in Dye-Sensitized Solar Cells: Deuterated Amino-Phenyl Acid Dyes on TiO2

    Directory of Open Access Journals (Sweden)

    Sergei Manzhos

    2013-03-01

    Full Text Available We present the first computational study of the effects of isotopic substitution on the operation of dye-sensitized solar cells. Ab initio molecular dynamics is used to study the effect of deuteration on light absorption, dye adsorption dynamics, the averaged over vibrations driving force to injection (∆Gi and regeneration (∆Gr, as well as on promotion of electron back-donation in dyes NK1 (2E,4E-2-cyano-5-(4-dimethylaminophenylpenta-2,4-dienoic acid and NK7 (2E,4E-2-cyano-5-(4-diphenylaminophenylpenta-2,4-dienoic acid adsorbed in monodentate molecular and bidentate bridging dissociative configurations on the anatase (101 surface of TiO2. Deuteration causes a red shift of the absorption spectrum of the dye/TiO2 complex by about 5% (dozens of nm, which can noticeably affect the overlap with the solar spectrum in real cells. The dynamics effect on the driving force to injection and recombination (the difference between the averaged <∆Gi,r> and ∆Gi,requil at the equilibrium configuration is strong, yet there is surprisingly little isotopic effect: the average driving force to injection <∆Gi> and to regeneration <∆Gr> changes by only about 10 meV upon deuteration. The nuclear dynamics enhance recombination to the dye ground state due to the approach of the electron-donating group to TiO2, yet this effect is similar for deuterated and non-deuterated dyes. We conclude that the nuclear dynamics of the C-H(D bonds, mostly affected by deuteration, might not be important for the operation of photoelectrochemical cells based on organic dyes. As the expectation value of the ground state energy is higher than its optimum geometry value (by up to 0.1 eV in the present case, nuclear motions will affect dye regeneration by recently proposed redox shuttle-dye combinations operating at low driving forces.

  3. A novel method for the biosynthesis of deuterated proteins with selective protonation at the aromatic rings of Phe, Tyr and Trp

    International Nuclear Information System (INIS)

    Rajesh, Sundaresan; Nietlispach, Daniel; Nakayama, Hiroshi; Takio, Koji; Laue, Ernest D.; Shibata, Takehiko; Ito, Yutaka

    2003-01-01

    A novel biosynthetic strategy is described for the preparation of deuterated proteins containing protons at the ring carbons of Phe, Tyr and Trp, using the aromatic amino acid precursor shikimic acid. Specific protonation at aromatic side chains, with complete deuteration at C α/β positions was achieved in proteins overexpressed in bacteria grown in shikimate-supplemented D 2 O medium. Co-expression of a shikimate transporter in prototrophic bacteria resulted in protonation levels of 62-79%, whereas complete labeling was accomplished using shikimate auxotrophic bacteria. Our labeling protocol permits the measurement of important aromatic side chain derived distance restraints in perdeuterated proteins that could be utilized to enhance the accuracy of NMR structures calculated using low densities of NOEs from methyl selectively protonated samples

  4. Selectively deuterated liquid crystalline cyanoazobenzene side-chain polyesters. 3. Investigations of laser induced segmental mobility by Fourier transform infrared spectroscopy

    DEFF Research Database (Denmark)

    Kulinna, Christian; Hvilsted, Søren; Hendann, Claudia

    1998-01-01

    The laser-induced anisotropy in thin films of an extensive number of cyanoazobenzene sidechain liquid crystalline polytetradecanedioates, -dodecanedioates, and -adipates selectively deuterated at different positions have been investigated with polarized FTIR spectroscopy. The analysis of the segm......The laser-induced anisotropy in thin films of an extensive number of cyanoazobenzene sidechain liquid crystalline polytetradecanedioates, -dodecanedioates, and -adipates selectively deuterated at different positions have been investigated with polarized FTIR spectroscopy. The analysis...... of the segmental orientation based on dichroic ratios of characteristic absorption bands shows that, in polyesters with long main-chain spacing (tetradecanedioates and dodecanedioates), not only the light sensitive azo chromophore but also the main-chain methylene segment and to a smaller extent the flexible...

  5. In situ-observation of the vertical motion of soil waters by means of deuterated water using the gamma/neutron method: Laboratory and field

    International Nuclear Information System (INIS)

    Moutonnet, P.; Couchat, P.; Brissaud, F.; Puard, M.; Pappalardo, A.

    1978-01-01

    In order to study water movements in the field, the gamma/neutron method for measuring deuterated water was investigated. A laboratory device is presented which supplies measurements on 5 ml soil solution samples. A probe for in situ experiments is studied in all its performances: Background, calibration (count rate versus volumetric deuterated water content) and resolution. A dispersive transport of D 2 O pulses on soil column is presented and checked with a numerical simulation model. Then simultaneous measurement of soil water content and D 2 O concentration by neutron moisture gauge and gamma/neutron probe enable us to interpret the evolution of D 2 O pulse with an experimental field irrigation. (orig.) [de

  6. Analysis of Mammalian Cell Proliferation and Macromolecule Synthesis Using Deuterated Water and Gas Chromatography-Mass Spectrometry

    Directory of Open Access Journals (Sweden)

    Victoria C. Foletta

    2016-10-01

    Full Text Available Deuterated water (2H2O, a stable isotopic tracer, provides a convenient and reliable way to label multiple cellular biomass components (macromolecules, thus permitting the calculation of their synthesis rates. Here, we have combined 2H2O labelling, GC-MS analysis and a novel cell fractionation method to extract multiple biomass components (DNA, protein and lipids from the one biological sample, thus permitting the simultaneous measurement of DNA (cell proliferation, protein and lipid synthesis rates. We have used this approach to characterize the turnover rates and metabolism of a panel of mammalian cells in vitro (muscle C2C12 and colon cancer cell lines. Our data show that in actively-proliferating cells, biomass synthesis rates are strongly linked to the rate of cell division. Furthermore, in both proliferating and non-proliferating cells, it is the lipid pool that undergoes the most rapid turnover when compared to DNA and protein. Finally, our data in human colon cancer cell lines reveal a marked heterogeneity in the reliance on the de novo lipogenic pathway, with the cells being dependent on both ‘self-made’ and exogenously-derived fatty acid.

  7. Temperature effect on life-time of electron-excited uranyl ion. III. Effect of deuteration of solvent

    International Nuclear Information System (INIS)

    Lotnik, S.V.; Khamidullina, L.A.; Kazakov, V.P.

    2001-01-01

    Effect of deuteration of solvent was detected. The effect appeared in significant difference of shape of curves of uranyl ion (UO 2 2+ )* life-time temperature dependences in electron-excited state (τ). The curves were plotted during heating of frozen up to 77 K H 2 SO 4 solutions in H 2 O and D 2 SO 4 solutions in D 2 O. It was shown that in the case of D 2 SO 4 τ value in glass-like solution was lower then in polycrystalline sample, whereas in frozen H 2 SO 4 solutions there was opposite picture. Detected isotope effect was explained just as different proceeding of phase transition in H 2 SO 4 and D 2 SO 4 solutions so significant decrease of probability of nonradiating deactivation of (UO 2 2+ )* absorbed on D 2 SO 4 ·4D 2 O crystallohydrate surface in comparison with (UO 2 2+ )* absorbed on H 2 SO 4 ·4H 2 O and H 2 SO 4 ·6.5H 2 O crystallohydrate surfaces [ru

  8. Thermal unimolecular decomposition of bicyclopropyl and deuterated analogues: infrared photoactivation as a diagnostic tool in mechanistic organic chemistry

    International Nuclear Information System (INIS)

    Farneth, W.E.; Thomsen, M.W.

    1982-01-01

    The infrared photochemistry of bicyclopropyl yields product mixtures that are not easily rationalized on the basis of the mechanistic scheme suggested by previous pyrolysis work. As a result of this inconsistency the thermal chemistry of bicyclopropyl and analogues deuterated specifically on one ring has been reexamined. A significant new reaction channel involving the chemically activated decomposition of cyclohexene to ethylene and butadiene has been demonstrated. Evidence for the involvement of chemically activated cyclohexene is as follows: (1) isotopic labeling studies implying a symmetric intermediate, (2) a pressure-dependent ratio of cyclohexene to butadiene and ethylene, (3) good agreement between experimental and calculated values for the unimolecular rate constant for retro-Diels-Alder decay of ''hot'' cyclohexene. A comprehensive mechanism for the unimolecular decay of bicyclopropyl is proposed. The important elements of this mechanism are a single first-formed 1,3 biradical common to all products and the intervention of chemical activation in the generation of several of the secondary products

  9. Commensurately modulated 1/4 and 1/5 phases of deuterated betaine calcium chloride dihydrate: a neutron structural study

    International Nuclear Information System (INIS)

    Hernandez, O.; Cousson, A.; Kiat, J.M.; Ecole Centrale des Arts et Manufactures, 92 - Chatenay-Malabry; Paulus, W.; Technische Hochschule Aachen; Ezpeleta, J.M.; Zuniga, F.J.

    1999-01-01

    The structures of the commensurate 1/4 and 1/5 phases of the displacively modulated compound D-BCCD [deuterated betaine (trimethylammonioacetate) calcium chloride dihydrate, i.e. (CD 3 ) 3 NCD 2 COOCaCl 2 (D 2 O) 2 or CaCl 2 x C 5 D 11 NO 2 x 2D 2 O] have been determined by single-crystal neutron diffraction at 100 and 68 K, respectively. The structural model of the 1/4 phase is found to be quite different from that obtained previously from X-ray diffraction data of the hydrogenated compound. This discrepancy comes from the fact that X-ray irradiation induces in this compound an unusual time-dependent decrease of the intensity of high-order satellite diffraction peaks. As a consequence and due to the commensurate nature of the phases investigated, X-ray diffraction failed to detect the large anharmonicity of the structural modulation which is clearly present in the two structures determined by neutron diffraction. (orig.)

  10. Discriminative stimulus properties of beta-phenylethylamine, deuterated beta-phenylethylamine, phenylethanolamine and some metabolites of phenylethylamine in rodents

    Energy Technology Data Exchange (ETDEWEB)

    Reid, D.; Goudie, A.J.

    1986-06-01

    The discriminative stimulus (cue) properties of phenylethylamine (PEA) were analysed in rodents in a conventional two lever FR10 operant drug discrimination task. Rats trained to discriminate phenylethylamine at 30 mg/kg showed complete dose-related generalization to PEA and to two potential PEA metabolites: phenylethanolamine (PEOH) and N-Methyl PEA (NMPEA). Only partial (50%) generalization was seen with N-Methylphenylethanolamine (NMPEOH), another potential PEA metabolite. The specificity of PEA's action as a discriminative stimulus was demonstrated by the finding that fenfluramine, a substituted phenylethylamine, failed to generalize to PEA even at high doses with marked behavioural effects which are known to have discriminative stimulus properties themselves. These data suggest that NMPEA and PEOH may be functionally important active metabolites of PEA, particularly if the major pathway of PEA metabolism to phenylacetic acid under the influence of MAO Type B is for any reason impaired. A long acting deuterium substituted form of PEA (alpha, alpha, d2 PEA), which is resistant to metabolism by MAO, produced complete dose-related generalization to the PEA cue but was more potent than PEA, due presumably to its resistance to metabolism by MAO. Deuterated PEA may therefore be a useful agent to use in future studies of the PEA cue, because the discriminability of PEA itself appears to be low due to its very rapid metabolism in vivo.

  11. Ground-based Detection of Deuterated Water in Comet C/2014 Q2 (Lovejoy) at IR Wavelengths

    Energy Technology Data Exchange (ETDEWEB)

    Paganini, L.; Mumma, M. J.; Villanueva, G. L. [Goddard Center for Astrobiology, NASA Goddard Space Flight Center, Greenbelt, MD (United States); Gibb, E. L. [Department of Physics and Astronomy, University of Missouri, St. Louis, MO (United States)

    2017-02-20

    We conducted a deep search for deuterated water (HDO) in the Oort Cloud comet C/2014 Q2 (Lovejoy), through infrared (IR) spectroscopy with NIRSPEC at the Keck Observatory. In this Letter, we present our detections of HDO and water (H{sub 2}O) in comet Lovejoy on 2015 February 4 (post-perihelion) after 1 hr integration on source. The IR observations allowed simultaneous detection of H{sub 2}O and HDO, yielding production rates of 5.9 ± 0.13 × 10{sup 29} and 3.6 ± 1.0 × 10{sup 26} molecules s{sup −1}, respectively. The simultaneous detection permitted accurate determination of the isotopic ratio (D/H) in water of 3.02 ± 0.87 × 10{sup −4}, i.e., larger than the value for water in terrestrial oceans (or Vienna Standard Mean Ocean Water, VSMOW) by a factor of 1.94 ± 0.56. This D/H ratio in water exceeds the value obtained independently at millimeter wavelengths (0.89 ± 0.25 VSMOW; pre-perihelion). We discuss these parameters in the context of origins and emphasize the need for contemporaneous measurements of HDO and H{sub 2}O.

  12. Ground-based Detection of Deuterated Water in Comet C/2014 Q2 (Lovejoy) at IR Wavelengths

    International Nuclear Information System (INIS)

    Paganini, L.; Mumma, M. J.; Villanueva, G. L.; Gibb, E. L.

    2017-01-01

    We conducted a deep search for deuterated water (HDO) in the Oort Cloud comet C/2014 Q2 (Lovejoy), through infrared (IR) spectroscopy with NIRSPEC at the Keck Observatory. In this Letter, we present our detections of HDO and water (H 2 O) in comet Lovejoy on 2015 February 4 (post-perihelion) after 1 hr integration on source. The IR observations allowed simultaneous detection of H 2 O and HDO, yielding production rates of 5.9 ± 0.13 × 10 29 and 3.6 ± 1.0 × 10 26 molecules s −1 , respectively. The simultaneous detection permitted accurate determination of the isotopic ratio (D/H) in water of 3.02 ± 0.87 × 10 −4 , i.e., larger than the value for water in terrestrial oceans (or Vienna Standard Mean Ocean Water, VSMOW) by a factor of 1.94 ± 0.56. This D/H ratio in water exceeds the value obtained independently at millimeter wavelengths (0.89 ± 0.25 VSMOW; pre-perihelion). We discuss these parameters in the context of origins and emphasize the need for contemporaneous measurements of HDO and H 2 O.

  13. Source of Nitrous Oxide Emissions during the Cow Manure Composting Process as Revealed by Isotopomer Analysis of and amoA Abundance in Betaproteobacterial Ammonia-Oxidizing Bacteria▿ †

    Science.gov (United States)

    Maeda, Koki; Toyoda, Sakae; Shimojima, Ryosuke; Osada, Takashi; Hanajima, Dai; Morioka, Riki; Yoshida, Naohiro

    2010-01-01

    A molecular analysis of betaproteobacterial ammonia oxidizers and a N2O isotopomer analysis were conducted to study the sources of N2O emissions during the cow manure composting process. Much NO2−-N and NO3−-N and the Nitrosomonas europaea-like amoA gene were detected at the surface, especially at the top of the composting pile, suggesting that these ammonia-oxidizing bacteria (AOB) significantly contribute to the nitrification which occurs at the surface layer of compost piles. However, the 15N site preference within the asymmetric N2O molecule (SP = δ15Nα − δ15Nβ, where 15Nα and 15Nβ represent the 15N/14N ratios at the center and end sites of the nitrogen atoms, respectively) indicated that the source of N2O emissions just after the compost was turned originated mainly from the denitrification process. Based on these results, the reduction of accumulated NO2−-N or NO3−-N after turning was identified as the main source of N2O emissions. The site preference and bulk δ15N results also indicate that the rate of N2O reduction was relatively low, and an increased value for the site preference indicates that the nitrification which occurred mainly in the surface layer of the pile partially contributed to N2O emissions between the turnings. PMID:20048060

  14. Visualization of root water uptake: quantification of deuterated water transport in roots using neutron radiography and numerical modeling.

    Science.gov (United States)

    Zarebanadkouki, Mohsen; Kroener, Eva; Kaestner, Anders; Carminati, Andrea

    2014-10-01

    Our understanding of soil and plant water relations is limited by the lack of experimental methods to measure water fluxes in soil and plants. Here, we describe a new method to noninvasively quantify water fluxes in roots. To this end, neutron radiography was used to trace the transport of deuterated water (D2O) into roots. The results showed that (1) the radial transport of D2O from soil to the roots depended similarly on diffusive and convective transport and (2) the axial transport of D2O along the root xylem was largely dominated by convection. To quantify the convective fluxes from the radiographs, we introduced a convection-diffusion model to simulate the D2O transport in roots. The model takes into account different pathways of water across the root tissue, the endodermis as a layer with distinct transport properties, and the axial transport of D2O in the xylem. The diffusion coefficients of the root tissues were inversely estimated by simulating the experiments at night under the assumption that the convective fluxes were negligible. Inverse modeling of the experiment at day gave the profile of water fluxes into the roots. For a 24-d-old lupine (Lupinus albus) grown in a soil with uniform water content, root water uptake was higher in the proximal parts of lateral roots and decreased toward the distal parts. The method allows the quantification of the root properties and the regions of root water uptake along the root systems. © 2014 American Society of Plant Biologists. All Rights Reserved.

  15. High-level expression and deuteration of sperm whale myoglobin: A study of its solvent structure by X-ray and neutron diffraction methods

    Energy Technology Data Exchange (ETDEWEB)

    Shu, F. [State Univ. of New York, Stony Brook, NY (United States); Ramakrishnan, V. [Brookhaven National Laboratory, Upton, NY (United States); Schoenborn, B.P. [Los Alamos National Laboratory, NM (United States)

    1994-12-31

    Neutron diffraction has become one of the best ways to study light atoms, such as hydrogens. Hydrogen however has a negative coherent scattering factor, and a large incoherent scattering factor, while deuterium has virtually no incoherent scattering, but a large positive coherent scattering factor. Beside causing high background due to its incoherent scattering, the negative coherent scattering of hydrogen tends to cancel out the positive contribution from other atoms in a neutron density map. Therefore a fully deuterated sample will yield better diffraction data with stronger density in the hydrogen position. On this basis, a sperm whale myoglobin gene modified to include part of the A cII protein gene has been cloned into the T7 expression system. Milligram amounts of fully deuterated holo-myoglobin have been obtained and used for crystallization. The synthetic sperm whale myoglobin crystallized in P2{sub 1} space group isomorphous with the native protein crystal. A complete X-ray diffraction dataset at 1.5{Angstrom} has been collected. This X-ray dataset, and a neutron data set collected previously on a protonated carbon-monoxymyoglobin crystal have been used for solvent structure studies. Both X-ray and neutron data have shown that there are ordered hydration layers around the protein surface. Solvent shell analysis on the neutron data further has shown that the first hydration layer behaves differently around polar and apolar regions of the protein surface. Finally, the structure of per-deuterated myoglobin has been refined using all reflections to a R factor of 17%.

  16. High-level expression and deuteration of sperm whale myoglobin: A study of its solvent structure by X-ray and neutron diffraction methods

    International Nuclear Information System (INIS)

    Shu, F.; Ramakrishnan, V.; Schoenborn, B.P.

    1994-01-01

    Neutron diffraction has become one of the best ways to study light atoms, such as hydrogens. Hydrogen however has a negative coherent scattering factor, and a large incoherent scattering factor, while deuterium has virtually no incoherent scattering, but a large positive coherent scattering factor. Beside causing high background due to its incoherent scattering, the negative coherent scattering of hydrogen tends to cancel out the positive contribution from other atoms in a neutron density map. Therefore a fully deuterated sample will yield better diffraction data with stronger density in the hydrogen position. On this basis, a sperm whale myoglobin gene modified to include part of the A cII protein gene has been cloned into the T7 expression system. Milligram amounts of fully deuterated holo-myoglobin have been obtained and used for crystallization. The synthetic sperm whale myoglobin crystallized in P2 1 space group isomorphous with the native protein crystal. A complete X-ray diffraction dataset at 1.5 Angstrom has been collected. This X-ray dataset, and a neutron data set collected previously on a protonated carbon-monoxymyoglobin crystal have been used for solvent structure studies. Both X-ray and neutron data have shown that there are ordered hydration layers around the protein surface. Solvent shell analysis on the neutron data further has shown that the first hydration layer behaves differently around polar and apolar regions of the protein surface. Finally, the structure of per-deuterated myoglobin has been refined using all reflections to a R factor of 17%

  17. Small-angle neutron scattering from the reconstituted TF sub 1 of H sup + -ATPase from thermophilic bacterium PS3 with deuterated subunits

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Yuji [Univ. of Tokyo (Japan) Brookhaven National Lab., Upton, NY (United States); Harada, Mitsuo [Univ. of Tokyo (Japan); Ohta, Shigeo; Kagawa, Yasuo; Aono, Osamu [Jichi Medical School, Tochigi (Japan); Schefer, J; Schoenborn, B P [Brookhaven National Lab., Upton (United States)

    1990-01-01

    Subunits {alpha}, {beta} and {gamma} of adenosine triphosphatase (H{sup +}-ATPase) from the thermophilic bacterium PS3 (TF{sub 1}) have been over-expressed in Escherichia coli. {alpha} and {beta} subunits deuterated to the level of 90% were obtained by culturing E. coli in {sup 2}H{sub 2}O medium. Both the subunits and the reconstituted {alpha}{beta}{gamma} complex, TF{sub 1}, which contain the deuterated components in various combinations, were studied in solution by small-angle neutron scattering. The individual shapes of the subunits and their organization in the {alpha}{beta}{gamma}-TF{sub 1} complex were examined using the techniques of selective deuteration and contrast variation. The {alpha} and {beta} subunits are well approximated as ellipsoids of revolution having minor semi-axes of 20{center dot}4({plus minus}0{center dot}4) and 20{center dot}0({plus minus}0{center dot}2) {angstrom}, and major semi-axes of 53{center dot}0({plus minus}1{center dot}4) and 55{center dot}8({plus minus}0{center dot}9) {angstrom}, respectively. In the TF{sub 1} complex, three {beta} subunits are aligned to form an equilateral triangle, with their major axes tilted by 35{degree} with respect to the 3-fold axis of the complex. The {beta}-{beta} distance is about 53 {angstrom}. Three {alpha} subunits are similarly arranged, positioned between the {beta} subunits, and with their direction of tilt opposite to that of the {beta} subunits. The centers of the {alpha} and {beta} subunits lie in the same plane, forming a hexagon. Adjacent subunits overlap in this model, suggesting that they are not simple ellipsoids of revolution.

  18. The deuteration of acetanilides

    International Nuclear Information System (INIS)

    Chin, S.K.; Collier, R.; Hutchinson, D.W.

    1982-01-01

    The base-catalysed exchange of a proton of the methyl groups in acetanilides can be used to incorporate deuterium into these amides. 4'-Hydroxyl-2[ 2 H]acetanilide (acetaminophen, paracetamol) can be prepared by the demethylation with boron tribromide of 4'-methoxy-2[ 2 H] acetamide obtained by this base-catalysed exchange. (author)

  19. Deuteration of acetanilides

    Energy Technology Data Exchange (ETDEWEB)

    Chin, S.K.; Collier, R.; Hutchinson, D.W. (Warwick Univ., Coventry (UK). Dept. of Chemistry and Molecular Sciences)

    1982-09-01

    The base-catalysed exchange of a proton of the methyl groups in acetanilides can be used to incorporate deuterium into these amides. 4'-Hydroxyl-2(/sup 2/H)acetanilide (acetaminophen, paracetamol) can be prepared by the demethylation with boron tribromide of 4'-methoxy-2(/sup 2/H) acetamide obtained by this base-catalysed exchange.

  20. Definitive difference among [DS-D2O], [DS-H2O] and [Bulk-D2O] cells in the deuterization and deuterium-reaction

    International Nuclear Information System (INIS)

    Arata, Yoshiaki; Zhang, Yue Chang

    2000-01-01

    We observed a new phenomena that the enormous amount of deuterium/hydrogen can be absorbed quickly as a 'solute-atom' into fine metal powders embedded inside a double-structure (DS) cathode in the electrolyses of D 2 O and H 2 O-electrolytes, respectively, but such highly deuterated powders can be produced only using DS-cathode immersed in D 2 O-electrolyte; [DS-D 2 O], and never generated in H 2 O-electrolyte even using the DS-cathode; [DS-H 2 O]. On the other hand, [Bulk-D 2 O] with bulk-cathode made by the bulk Pd metal never produces highly deuterated metal as mentioned above even though using D 2 O-electrolyte. In short, the deuterium-concentration generating in [Bulk-D 2 O] is found to be much lower than that in [DS-D 2 O]. As a result, because of reason mentioned above, in marked contrast to the case with the [DS-D 2 O], neither excess heat nor 4 He production are observed with both [DS-H 2 O] and [Bulk-D 2 O]. (author)

  1. Application of the deuterated retinol dilution technique to detect changes in hepatic retinol reserves in infants who receive high dose vitamin A supplements

    International Nuclear Information System (INIS)

    Penny, M.; Lanata, C.; Butron, B.; Haskell, M.; Brown, K.

    1997-01-01

    The purpose of this pilot study is to determine whether the deuterated retinol dilution technique can detect changes in hepatic vitamin A reserves in Peruvian infants in response to supplementation with vitamin A palmitate. Approximately 40 infants, 9 months of age, will be recruited for the study and randomly assigned to four treatment groups. Hepatic vitamin A reserves will be estimated using the deuterated retinol dilution technique before and after administration of a single supplement containing either 0, 7.5, 15, or 30 mg RE as retinyl palmitate in corn oil. Mean hepatic vitamin A reserves will be calculated based on the plasma isotopic ratio of d4-retinol:retinol as per Furr, et. al. Hepatic vitamin A reserves will be compared within groups before and after supplementation, and among the four groups. The mean change in hepatic vitamin A reserves across the four treatment groups will be examined in relation to the amount of vitamin A supplement administered, using regression analysis. The results of the pilot study will provide information on the size and variation of hepatic vitamin A reserves in 9-month old Peruvian infants. This information will be useful for calculating samples sizes to evaluate vitamin A intervention strategies by estimating changes in hepatic vitamin A stores in this age group, using the DRD technique. (author)

  2. Application of the deuterated retinol dilution technique to detect changes in hepatic retinol reserves in infants who receive high dose vitamin A supplements

    Energy Technology Data Exchange (ETDEWEB)

    Penny, M; Lanata, C; Butron, B [Instituto de Investigacion Nutricional, Lima (Peru); Haskell, M; Brown, K [Programme in International Nutrition, Univ. of California, Davis, CA (United States)

    1998-12-31

    The purpose of this pilot study is to determine whether the deuterated retinol dilution technique can detect changes in hepatic vitamin A reserves in Peruvian infants in response to supplementation with vitamin A palmitate. Approximately 40 infants, 9 months of age, will be recruited for the study and randomly assigned to four treatment groups. Hepatic vitamin A reserves will be estimated using the deuterated retinol dilution technique before and after administration of a single supplement containing either 0, 7.5, 15, or 30 mg RE as retinyl palmitate in corn oil. Mean hepatic vitamin A reserves will be calculated based on the plasma isotopic ratio of d4-retinol:retinol as per Furr, et. al. Hepatic vitamin A reserves will be compared within groups before and after supplementation, and among the four groups. The mean change in hepatic vitamin A reserves across the four treatment groups will be examined in relation to the amount of vitamin A supplement administered, using regression analysis. The results of the pilot study will provide information on the size and variation of hepatic vitamin A reserves in 9-month old Peruvian infants. This information will be useful for calculating samples sizes to evaluate vitamin A intervention strategies by estimating changes in hepatic vitamin A stores in this age group, using the DRD technique. (author). 12 refs, 3 figs.

  3. Demonstration of In situ Anaerobic Transformation of Toluene and Xylene Using Single-Well Push-Pull Tests and Deuterated BTEX Surrogates

    Science.gov (United States)

    Field, J. A.; Reusser, D. E.; Beller, H. R.; Istok, J. D.

    2001-12-01

    Obtaining unambiguous evidence of in-situ transformation of benzene, toluene, ethylbenzene and xylene (BTEX) in the subsurface is a difficult task. Recently, benzylsuccinic acid and its methyl analogues were shown to be unequivocal degradation products of anaerobic toluene and xylene biodegradation. Conducting tracer tests at BTEX-contaminated field sites is problematic because background contaminant concentrations potentially interfere with the interpretation of field test data. To avoid the time and cost associated with removing background contaminants, alternative approaches are needed. Deuterated analogs of toluene and xylene are well-suited for use in field tracer tests because they are inexpensive and can be distinguished analytically from background toluene and xylene. In this study, single-well push-pull tests, in which deuterated toluene and xylene were injected, were performed to assess the in-situ anaerobic biotransformation of toluene and xylene in BTEX-contaminated wells. A total of 4 single-well push-pull tests were conducted at BTEX-contaminated field sites near Portland, OR and Kansas City, KS. Test solutions consisting of 100 mg/L bromide, 250 mg/L nitrate, 0.4 to 2.5 mg/L toluene-d8, and 0.4 to 1.0 mg/L o-xylene-d10.were injected at a rate of 0.5 - 2 L/min. During the extraction phase, samples were taken daily to biweekly for up to 30 days. Samples for volatile organic analytes were collected in 40-mL volatile organic analysis (VOA) vials without headspace. Samples for BSA and methyl-BSA were collected in 1 L glass bottles and preserved with 5% (w/w) formalin. Samples were shipped on ice and stored at 4 C until analysis. Unambiguous evidence of toluene and xylene biotransformation was obtained with the in-situ formation of BSA and methyl-BSA. The concentrations of BSA ranged from below the detection limit (0.2 ug/L) to 1.5 ug/L. The concentrations of methyl-BSA ranged from below detection to the quantitation limit (0.7 ug/L). The highest BSA

  4. Preparation of. alpha. -deuterated L-amino acids using E. coli cells containing tryptophanase. Poluchenie. alpha. -dejterirovannykh L-aminokislot s ispol'zovaniem kletok E. coli, soderzhashchikh triptofanazy

    Energy Technology Data Exchange (ETDEWEB)

    Faleev, N G; Ruvinov, S B; Saporovskaya, M B; Belikov, V M; Zakomyrdina, L N; Sakharova, I S; Torchinskij, Yu M [AN SSSR, Moscow (USSR). Inst. Ehlementoorganicheskikh Soedinenij AN SSSR, Moscow (USSR). Inst. Molekulyarnoj Biologii AN SSSR, Moscow (USSR)

    1989-10-01

    Method for preparation of a series of {alpha}-deuterated L-amino acids of high optical purity with quantitative chemica yield, suing stereospecific isotopic exchange in D{sub 2}O under the effect of E.coli cells with high tryptophanase activity was developed.

  5. Loss of ammonia during electron-transfer dissociation of deuterated peptides as an inherent gauge of gas-phase hydrogen scrambling

    DEFF Research Database (Denmark)

    Rand, Kasper D; Zehl, Martin; Jensen, Ole Nørregaard

    2010-01-01

    detected by a depletion of deuterium when deuterated ammonia is lost from peptides during ETD. This straightforward method requires no modifications to the experimental workflow and has the great advantage that the occurrence of hydrogen scrambling can be directly detected in the actual peptides analyzed......The application of electron-transfer dissociation (ETD) to obtain single-residue resolution in hydrogen exchange-mass spectrometry (HX-MS) experiments has recently been demonstrated. For such measurements, it is critical to ensure that the level of gas-phase hydrogen scrambling is negligible. Here...... we utilize the abundant loss of ammonia upon ETD of peptide ions as a universal reporter of positional randomization of the exchangeable hydrogens (hydrogen scrambling) during HX-ETD experiments. We show that the loss of ammonia from peptide ions proceeds without depletion of deuterium when employing...

  6. Infrared and Raman study of the fast internal motions of non-rigid molecules in condensed state: method of selective deuteration

    International Nuclear Information System (INIS)

    Lascombe, J.; Cavagnat, D.; Lassegues, J.C.; Rafilipomanana, C.

    1983-01-01

    The dynamical behaviour of non-rigid molecules in the gas state is now well known but very little information is available on these molecules in condensed state. The authors present a method of study based on the analysis of the infrared and Raman spectra of selectively deuterated molecules. It is applied to the nitromethane and cyclopentene molecules which provide respectively characteristic examples of methyl internal rotation and ring-puckering motion. In each case, an isolated -C0 or -CD oscillator is modulated by the internal motion and several γ(CH) or γ(CD) bands are observed as a result of the dependence of the vibrational frequency of the oscillator on its conformational situation. Moreover, in the case of crystalline nitromethane a detailed study of the temperature dependence of the band profiles allows the main mechanism of relaxation of the -CH oscillator to be deduced. (orig.)

  7. Poly(dA-dT).poly(dA-dT) two-pathway proton exchange mechanism. Effect of general and specific base catalysis on deuteration rates

    International Nuclear Information System (INIS)

    Hartmann, B.; Leng, M.; Ramstein, J.

    1986-01-01

    The deuteration rates of the poly(dA-dT).poly(dA-dT) amino and imino protons have been measured with stopped-flow spectrophotometry as a function of general and specific base catalyst concentration. Two proton exchange classes are found with time constants differing by a factor of 10 (4 and 0.4 s-1). The slower class represents the exchange of the adenine amino protons whereas the proton of the faster class has been assigned to the thymine imino proton. The exchange rates of these two classes of protons are independent of general and specific base catalyst concentration. This very characteristic behavior demonstrates that in our experimental conditions the exchange rates of the imino and amino protons in poly(dA-dT).poly(dA-dT) are limited by two different conformational fluctuations. We present a three-state exchange mechanism accounting for our experimental results

  8. Crystal structure of the sodium cobaltate deuterate superconductor NaxCoO2ṡ4xD2O (x≈1/3)

    Science.gov (United States)

    Jorgensen, J. D.; Avdeev, M.; Hinks, D. G.; Burley, J. C.; Short, S.

    2003-12-01

    Neutron and x-ray powder diffraction have been used to investigate the crystal structures of a sample of the newly-discovered superconducting sodium cobaltate deuterate compound with composition Na0.31(3)CoO2ṡ1.25(2)D2O and its anhydrous parent compound Na0.61(1)CoO2. The anhydrous parent compound Na0.61(1)CoO2 has two partially occupied Na sites sandwiched, in the same plane, between CoO2 layers. When Na is removed to make the superconducting composition, the Na site that experiences the strongest Na Co repulsion is emptied while the occupancy of the other Na site is reduced to about one third. The deuterate superconducting compound is formed by coordinating four D2O molecules (two above and two below) to each remaining Na ion in a way that gives Na O distances nearly equal to those in the parent compound. One deuteron of the D2O molecule is hydrogen bonded to an oxygen atom in the CoO2 plane and the oxygen atom and the second deuteron of each D2O molecule lie approximately in a plane between the Na layer and the CoO2 layers. This coordination of Na by four D2O molecules leads in a straightforward way to ordering of the Na ions and D2O molecules consistent with the observation of additional shorter-range scattering features in the diffraction data. The sample studied here, which has Tc=4.5 K, has a refined composition of Na0.31(3)CoO2ṡ1.25(2)D2O, in agreement with the expected 1:4 ratio of Na to D2O. These results show that the optimal superconducting composition should be viewed as a specific hydrated compound, not a solid solution of Na and D2O (H2O) in NaxCoO2ṡD2O. The hydrated superconducting compound may be stable over a limited range of Na and D2O concentration, but studies of Tc and other physical properties vs Na or D2O composition should be viewed with caution until it is verified that the compound remains in the same phase over the composition range of the study.

  9. Crystal structure of the sodium cobaltate deuterate superconductor NaxCoO2·4xD2O (x≅(1/3))

    International Nuclear Information System (INIS)

    Jorgensen, J.D.; Avdeev, M.; Hinks, D.G.; Burley, J.C.; Short, S.

    2003-01-01

    Neutron and x-ray powder diffraction have been used to investigate the crystal structures of a sample of the newly-discovered superconducting sodium cobaltate deuterate compound with composition Na 0.31(3) CoO 2 ·1.25(2)D 2 O and its anhydrous parent compound Na 0.61(1) CoO 2 . The anhydrous parent compound Na 0.61(1) CoO 2 has two partially occupied Na sites sandwiched, in the same plane, between CoO 2 layers. When Na is removed to make the superconducting composition, the Na site that experiences the strongest Na-Co repulsion is emptied while the occupancy of the other Na site is reduced to about one third. The deuterate superconducting compound is formed by coordinating four D 2 O molecules (two above and two below) to each remaining Na ion in a way that gives Na-O distances nearly equal to those in the parent compound. One deuteron of the D 2 O molecule is hydrogen bonded to an oxygen atom in the CoO 2 plane and the oxygen atom and the second deuteron of each D 2 O molecule lie approximately in a plane between the Na layer and the CoO 2 layers. This coordination of Na by four D 2 O molecules leads in a straightforward way to ordering of the Na ions and D 2 O molecules consistent with the observation of additional shorter-range scattering features in the diffraction data. The sample studied here, which has T c =4.5 K, has a refined composition of Na 0.31(3) CoO 2 ·1.25(2)D 2 O, in agreement with the expected 1:4 ratio of Na to D 2 O. These results show that the optimal superconducting composition should be viewed as a specific hydrated compound, not a solid solution of Na and D 2 O (H 2 O) in Na x CoO 2 ·D 2 O. The hydrated superconducting compound may be stable over a limited range of Na and D 2 O concentration, but studies of T c and other physical properties vs Na or D 2 O composition should be viewed with caution until it is verified that the compound remains in the same phase over the composition range of the study

  10. Nitrogen-detected TROSY yields comparable sensitivity to proton-detected TROSY for non-deuterated, large proteins under physiological salt conditions

    Energy Technology Data Exchange (ETDEWEB)

    Takeuchi, Koh [National Institute for Advanced Industrial Science and Technology, Molecular Profiling Research Center for Drug Discovery (Japan); Arthanari, Haribabu [Harvard Medical School, Department of Biochemistry and Molecular Pharmacology (United States); Imai, Misaki [Japan Biological Informatics Consortium, Research and Development Department (Japan); Wagner, Gerhard, E-mail: gerhard-wagner@hms.harvard.edu [Harvard Medical School, Department of Biochemistry and Molecular Pharmacology (United States); Shimada, Ichio, E-mail: shimada@iw-nmr.f.u-tokyo.ac.jp [National Institute for Advanced Industrial Science and Technology, Molecular Profiling Research Center for Drug Discovery (Japan)

    2016-02-15

    Direct detection of the TROSY component of proton-attached {sup 15}N nuclei ({sup 15}N-detected TROSY) yields high quality spectra with high field magnets, by taking advantage of the slow {sup 15}N transverse relaxation. The slow transverse relaxation and narrow line width of the {sup 15}N-detected TROSY resonances are expected to compensate for the inherently low {sup 15}N sensitivity. However, the sensitivity of {sup 15}N-detected TROSY in a previous report was one-order of magnitude lower than in the conventional {sup 1}H-detected version. This could be due to the fact that the previous experiments were performed at low salt (0–50 mM), which is advantageous for {sup 1}H-detected experiments. Here, we show that the sensitivity gap between {sup 15}N and {sup 1}H becomes marginal for a non-deuterated, large protein (τ{sub c} = 35 ns) at a physiological salt concentration (200 mM). This effect is due to the high salt tolerance of the {sup 15}N-detected TROSY. Together with the previously reported benefits of the {sup 15}N-detected TROSY, our results provide further support for the significance of this experiment for structural studies of macromolecules when using high field magnets near and above 1 GHz.

  11. Use of a Deuterated Internal Standard with Pyrolysis-GC/MS Dimeric Marker Analysis to Quantify Tire Tread Particles in the Environment

    Directory of Open Access Journals (Sweden)

    Julie M. Panko

    2012-11-01

    Full Text Available Pyrolysis(pyr-GC/MS analysis of characteristic thermal decomposition fragments has been previously used for qualitative fingerprinting of organic sources in environmental samples. A quantitative pyr-GC/MS method based on characteristic tire polymer pyrolysis products was developed for tread particle quantification in environmental matrices including soil, sediment, and air. The feasibility of quantitative pyr-GC/MS analysis of tread was confirmed in a method evaluation study using artificial soil spiked with known amounts of cryogenically generated tread. Tread concentration determined by blinded analyses was highly correlated (r2 ³ 0.88 with the known tread spike concentration. Two critical refinements to the initial pyrolysis protocol were identified including use of an internal standard and quantification by the dimeric markers vinylcyclohexene and dipentene, which have good specificity for rubber polymer with no other appreciable environmental sources. A novel use of deuterated internal standards of similar polymeric structure was developed to correct the variable analyte recovery caused by sample size, matrix effects, and ion source variability. The resultant quantitative pyr-GC/MS protocol is reliable and transferable between laboratories.

  12. Use of a deuterated internal standard with pyrolysis-GC/MS dimeric marker analysis to quantify tire tread particles in the environment.

    Science.gov (United States)

    Unice, Kenneth M; Kreider, Marisa L; Panko, Julie M

    2012-11-08

    Pyrolysis(pyr)-GC/MS analysis of characteristic thermal decomposition fragments has been previously used for qualitative fingerprinting of organic sources in environmental samples. A quantitative pyr-GC/MS method based on characteristic tire polymer pyrolysis products was developed for tread particle quantification in environmental matrices including soil, sediment, and air. The feasibility of quantitative pyr-GC/MS analysis of tread was confirmed in a method evaluation study using artificial soil spiked with known amounts of cryogenically generated tread. Tread concentration determined by blinded analyses was highly correlated (r2 ≥ 0.88) with the known tread spike concentration. Two critical refinements to the initial pyrolysis protocol were identified including use of an internal standard and quantification by the dimeric markers vinylcyclohexene and dipentene, which have good specificity for rubber polymer with no other appreciable environmental sources. A novel use of deuterated internal standards of similar polymeric structure was developed to correct the variable analyte recovery caused by sample size, matrix effects, and ion source variability. The resultant quantitative pyr-GC/MS protocol is reliable and transferable between laboratories.

  13. Dietary vitamin A intakes of Filipino elders with adequate or low liver vitamin A concentrations as assessed by the deuterated-retinol-dilution method: implications for dietary requirements.

    Science.gov (United States)

    Ribaya-Mercado, Judy D; Solon, Florentino S; Fermin, Liza S; Perfecto, Christine S; Solon, Juan Antonio A; Dolnikowski, Gregory G; Russell, Robert M

    2004-04-01

    The vitamin A requirements of elderly humans have not been studied. In a cross-sectional study of 60-88-y-old men (n = 31) and women (n = 31) in rural Philippines, we assessed the dietary intakes of elders with adequate (> or = 0.07 micromol/g) or low (value for elders. The mean (+/- SD) vitamin A intakes of the men and women with adequate vitamin A in liver were 135 +/- 86 and 134 +/- 104 microg retinol activity equivalents (RAE)/d, respectively; intakes of the men and women with low vitamin A in liver were 75 +/- 53 and 60 +/- 27 microg RAE/d, respectively. Total-body vitamin A or liver vitamin A but not serum retinol correlated with dietary RAE, preformed vitamin A, beta-carotene, fat, and protein. An estimated acceptable or sufficient dietary vitamin A intake associated with adequate liver vitamin A concentrations in elders is 6.45 microg RAE/kg body wt; for a reference 76-kg man and a 61-kg woman, these values are approximately 500 and 400 microg RAE/d, respectively. The dietary vitamin A intakes of elders with adequate or low liver vitamin A concentrations as estimated by use of the deuterated-retinol-dilution technique are useful for assessing vitamin A requirements.

  14. On the hydrophilicity of polyzwitterion poly (N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropane sulfonate) in water, deuterated water, and aqueous salt solutions.

    Science.gov (United States)

    Hildebrand, Viet; Laschewsky, André; Zehm, Daniel

    2014-01-01

    A series of zwitterionic model polymers with defined molar masses up to 150,000 Da and defined end groups are prepared from sulfobetaine monomer N,N-dimethyl-N-(3-(methacrylamido)propyl)ammoniopropanesulfonate (SPP). Polymers are synthesized by reversible addition-fragmentation chain transfer polymerization (RAFT) using a functional chain transfer agent labeled with a fluorescent probe. Their upper critical solution temperature-type coil-to-globule phase transition in water, deuterated water, and various salt solutions is studied by turbidimetry. Cloud points increase with polyzwitterion concentration and molar mass, being considerably higher in D2O than in H2O. Moreover, cloud points are strongly affected by the amount and nature of added salts. Typically, they increase with increasing salt concentration up to a maximum value, whereas further addition of salt lowers the cloud points again, mostly down to below freezing point. The different salting-in and salting-out effects of the studied anions can be correlated with the Hofmeister series. In physiological sodium chloride solution and in phosphate buffered saline (PBS), the cloud point is suppressed even for high molar mass samples. Accordingly, SPP-polymers behave strongly hydrophilic under most conditions encountered in biomedical applications. However, the direct transfer of results from model studies in D2O, using, e.g. (1)H NMR or neutron scattering techniques, to 'normal' systems in H2O is not obvious.

  15. "Anomalous" excitation in hydrogen-bonded molecular crystals - a Raman scattering study of specifically deuterated acetanilide (C 6D 5-CONH-CD 3)

    Science.gov (United States)

    Sauvajol, J. L.; De Nunzio, G.; Almairac, R.; Moret, J.; Barthés, M.; Bataillon, Place E.

    1991-01-01

    The focus of experimental and theoretical works about crystalline Acetanilide has been the "anomalous" temperature-dependent ir absorption and Raman peaks at about 1650 cm -1 and the multiband structure in the N-H stretch region. A lively discussion about the assignment of these "anomalous" bands has arisen and is still in progress. The present Raman experiments should be placed in this context as an attempt to identify the molecular degrees of freedom which originate the "anomalous" bands. In this aim Raman experiments have been performed on specifically deuterated Acetanilide [C 6D 5-CONH-CD 3] single crystal in the low-frequency (phonon) and C=O stretching regions. On cooling a distinct band at about 1495 cm -1 increases in intensity. We assign this peak to the equivalent of the 1650 cm -1 band in Acetanilide. The temperature dependence of this Raman line was studied. The results are discussed in the light of the models proposed to explain the anomalous behaviour of the 1650 cm -1 Raman line in Acetanilide.

  16. Early deuteration steps of Pd- and Ta/Pd- catalyzed Mg{sub 70}Al{sub 30} thin films observed at room temperature

    Energy Technology Data Exchange (ETDEWEB)

    Harrower, Christopher; Kalisvaart, Peter; Mitlin, David [Chemical and Materials Engineering, University of Alberta, Alberta T6G 2V4 (Canada); National Research Council Canada, National Institute for Nanotechnology, Edmonton, Alberta T6G 2M9 (Canada); Poirier, Eric; Fritzsche, Helmut [National Research Council Canada, SIMS, Canadian Neutron Beam Centre, Chalk River, Ontario K0J 1J0 (Canada); Satija, Sushil [National Institute of Standards and Technology, Center for Neutron Research, Gaithersburg, MD 20899 (United States); Akgun, Bulent [National Institute of Standards and Technology, Center for Neutron Research, Gaithersburg, MD 20899 (United States); Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742 (United States)

    2010-10-15

    Deuterium absorption in Mg{sub 70}Al{sub 30} thin films coated with a Pd layer and a Ta/Pd bilayer were investigated using in situ neutron reflectometry at room temperature and deuterium pressures up to 1.3 bar. The approach used provides a detailed profile, at the nanoscale, of the deuterium content inside the specific layers that constitute the films. It is found that Mg{sub 70}Al{sub 30} can store up to 5 wt.% under these mild conditions following a two-step mechanism. The latter involves the deuteration of the top and bottom catalyst layers first, followed by the main Mg{sub 70}Al{sub 30} layer. The presence of deuterium throughout the films in the early absorption stages evidences atomic deuterium spillover from the catalyst layers. The addition of a Ta layer between the Pd and Mg{sub 70}Al{sub 30} was found to allow observable absorption at a pressure 10 times lower than on the Ta-free sample, without affecting the storage capacity. Our measurements imply that this improvement in kinetics is due to a lowering of the nucleation barrier for the formation of the hydride phase in the Mg{sub 70}Al{sub 30} layer. (author)

  17. Nascent VLDL from liver perfusions of cynomolgus monkeys are preferentially enriched in RRR- compared with SRR-alpha-tocopherol: Studies using deuterated tocopherols

    International Nuclear Information System (INIS)

    Traber, M.G.; Rudel, L.L.; Burton, G.W.; Hughes, L.; Ingold, K.U.; Kayden, H.J.

    1990-01-01

    The transport and secretion of vitamin E in lipoproteins have been studied in cynomolgus monkeys fed tocopherols labeled with different amounts of deuterium. The animals were fed a single dose of vitamin E containing 60 mumol of each 2R,4'R,8'R-alpha-(5,7-(C2H3)2)tocopheryl acetate (d6-RRR-alpha-tocopheryl acetate; alpha-tocopherol with natural stereochemistry), 2S,4'R,8'R-alpha-5-(C2H3)tocopheryl acetate (d3-SRR-alpha-tocopheryl acetate; alpha-tocopherol with unnatural stereochemistry), and 2R,4'R,8'R-gamma-(3,4-2H)tocopherol (d2-RRR-gamma-tocopherol; gamma-tocopherol with natural stereochemistry). Chylomicrons, as well as the other plasma lipoproteins, contained equal concentrations of all three tocopherols at the earliest time points after feeding suggesting that all three tocopherols were absorbed equally. At later times plasma lipoproteins became preferentially enriched in d6-RRR-alpha-tocopherol. This is likely to be due to hepatic secretion of VLDL (very low density lipoproteins) and other lipoproteins, which were enriched in d6-RRR-alpha-tocopherol, as demonstrated in the lipoproteins isolated from perfused livers that had been obtained 24 h following the administration of the deuterated tocopherols. Taken together these data demonstrate that the liver, not the intestine, is the likely site of discrimination between tocopherol isomers and that the liver secretes nascent lipoproteins preferentially enriched in d6-RRR-alpha-tocopherol

  18. Theoretical modeling of deuteration-induced shifts of the 0-0 bands in absorption spectra of selected aromatic amines: the role of the double-well potential.

    Science.gov (United States)

    Andrzejak, Marcin; Kolek, Przemysław

    2013-12-05

    The harmonic approximation fails for inversion of the NH2 group in the ground state of aromatic amines as this vibration is characterized by a symmetric double-well potential with relatively small energy barrier. In such cases, the standard harmonic vibrational analysis is inapplicable: the inversion frequency calculated for the bottom of the potential well is strongly overestimated, while it attains imaginary values for the planar conformation of the molecule. The model calculations are discussed taking explicitly into account the presence of the double-well potential. The study is initially focused on reproduction of the deuteration-induced shifts of the 0-0 absorption band for anthranilic acid. The (incorrect) harmonic frequency of the NH2 inversion is replaced by a better one, obtained from numerical calculations employing a simple, quartic-quadratic model for the double-well potential, which is parametrized using just the harmonic frequency of the inversion and the height of the energy barrier. This operation brings theoretical results to qualitative agreement with experiment. A still better match is achieved with a modified version of the model that accounts for mixing of the NH2 inversion mode with other normal modes while retaining the initial simplicity of one-dimensional approach. The corrected results show surprisingly good accuracy, with deviations of the calculated shifts from the experimental values reduced to less than 5 cm(-1). In order to test the performance of the model for systems with higher energy barrier for the NH2 inversion, we have measured the LIF excitation spectra of three different amminobenzonitriles. Partial assignment of the 0-0 bands has been achieved based on their relative intensities for samples with different isotopic exchange ratios. Calculated shifts are in excellent agreement with experimental values for the identified bands. Theoretical predictions are used to complete the assignment of the 0-0 bands in the spectra of the

  19. Seasonal nutrient dynamics and biomass quality of giant reed (Arundo donax L. and miscanthus (Miscanthus x giganteus Greef et Deuter as energy crops

    Directory of Open Access Journals (Sweden)

    Nicoletta Nassi o Di Nasso

    2011-08-01

    Full Text Available The importance of energy crops in displacing fossil fuels within the energy sector in Europe is growing. Among energy crops, the use of perennial rhizomatous grasses (PRGs seems promising owing to their high productivity and their nutrient recycling that occurs during senescence. In particular, nutrient requirements and biomass quality have a fundamental relevance to biomass systems efficiency. The objective of our study was to compare giant reed (Arundo donax L. and miscanthus (Miscanthus × giganteus Greef et Deuter in terms of nutrient requirements and cellulose, hemicelluloses and lignin content. This aim was to identify, in the Mediterranean environment, the optimal harvest time that may combine, beside a high biomass yield, high nutrient use efficiency and a good biomass quality for second generation biofuel production. The research was carried out in 2009, in San Piero a Grado, Pisa (Central Italy; latitude 43°41’ N, longitude 10°21’ E, on seven-year-old crops in a loam soil characterised by good water availability. Maximum above-ground nutrient contents were generally found in summer. Subsequently, a decrease was recorded; this suggested a nutrient remobilisation from above-ground biomass to rhizomes. In addition, miscanthus showed the highest N, P, and K use efficiency, probably related to its higher yield and its C4 pathway. Regarding biomass quality, stable values of cellulose (38%, hemicelluloses (25% and lignin (8% were reported from July onwards in both crops. Hence, these components appear not to be discriminative parameters in the choice of the harvest time in the Mediterranean environment. In conclusion, our results highlighted that, in our environment, a broad harvest period (from late autumn to winter seems suitable for these PRGs. However, further research is required to evaluate the role of rhizomes in nutrient storage and supply during the growing season, as well as ecological and productive performances in marginal

  20. Optimal degree of protonation for {sup 1}H detection of aliphatic sites in randomly deuterated proteins as a function of the MAS frequency

    Energy Technology Data Exchange (ETDEWEB)

    Asami, Sam [Helmholtz-Zentrum Muenchen (HMGU), Deutsches Forschungszentrum fuer Gesundheit und Umwelt (HMGU) (Germany); Szekely, Kathrin; Schanda, Paul; Meier, Beat H. [Eidgenoessische Technische Hochschule Zuerich (ETH Zuerich) (Switzerland); Reif, Bernd, E-mail: reif@tum.de [Helmholtz-Zentrum Muenchen (HMGU), Deutsches Forschungszentrum fuer Gesundheit und Umwelt (HMGU) (Germany)

    2012-10-15

    The {sup 1}H dipolar network, which is the major obstacle for applying proton detection in the solid-state, can be reduced by deuteration, employing the RAP (Reduced Adjoining Protonation) labeling scheme, which yields random protonation at non-exchangeable sites. We present here a systematic study on the optimal degree of random sidechain protonation in RAP samples as a function of the MAS (magic angle spinning) frequency. In particular, we compare {sup 1}H sensitivity and linewidth of a microcrystalline protein, the SH3 domain of chicken {alpha}-spectrin, for samples, prepared with 5-25 % H{sub 2}O in the E. coli growth medium, in the MAS frequency range of 20-60 kHz. At an external field of 19.96 T (850 MHz), we find that using a proton concentration between 15 and 25 % in the M9 medium yields the best compromise in terms of sensitivity and resolution, with an achievable average {sup 1}H linewidth on the order of 40-50 Hz. Comparing sensitivities at a MAS frequency of 60 versus 20 kHz, a gain in sensitivity by a factor of 4-4.5 is observed in INEPT-based {sup 1}H detected 1D {sup 1}H,{sup 13}C correlation experiments. In total, we find that spectra recorded with a 1.3 mm rotor at 60 kHz have almost the same sensitivity as spectra recorded with a fully packed 3.2 mm rotor at 20 kHz, even though {approx}20 Multiplication-Sign less material is employed. The improved sensitivity is attributed to {sup 1}H line narrowing due to fast MAS and to the increased efficiency of the 1.3 mm coil.

  1. Kinetics of di(2-ethylhexyl) phthalate (DEHP) and mono(2-ethylhexyl) phthalate in blood and of DEHP metabolites in urine of male volunteers after single ingestion of ring-deuterated DEHP

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, Winfried, E-mail: kessler@helmholtz-muenchen.de [Institute of Molecular Toxicology and Pharmacology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, D-85764 Neuherberg (Germany); Numtip, Wanwiwa [Institute of Molecular Toxicology and Pharmacology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, D-85764 Neuherberg (Germany); Völkel, Wolfgang; Seckin, Elcim [Department of Chemical Safety and Toxicology, Bavarian Health and Food Safety Authority, Pfarrstrasse 3, D-80538 München (Germany); Csanády, György A. [Institute of Molecular Toxicology and Pharmacology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, D-85764 Neuherberg (Germany); Institut für Toxikologie und Umwelthygiene, Technische Universität München, München (Germany); Pütz, Christian [Institute of Molecular Toxicology and Pharmacology, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, D-85764 Neuherberg (Germany); and others

    2012-10-15

    The plasticizer di(2-ethylhexyl) phthalate (DEHP) is suspected to induce antiandrogenic effects in men via its metabolite mono(2-ethylhexyl) phthalate (MEHP). However, there is only little information on the kinetic behavior of DEHP and its metabolites in humans. The toxikokinetics of DEHP was investigated in four male volunteers (28–61 y) who ingested a single dose (645 ± 20 μg/kg body weight) of ring-deuterated DEHP (DEHP-D{sub 4}). Concentrations of DEHP-D{sub 4}, of free ring-deuterated MEHP (MEHP-D{sub 4}), and the sum of free and glucuronidated MEHP-D{sub 4} were measured in blood for up to 24 h; amounts of the monoesters MEHP-D{sub 4}, ring-deuterated mono(2-ethyl-5-hydroxyhexyl) phthalate and ring-deuterated mono(2-ethyl-5-oxohexyl) phthalate were determined in urine for up to 46 h after ingestion. The bioavailability of DEHP-D{sub 4} was surprisingly high with an area under the concentration-time curve until 24 h (AUC) amounting to 50% of that of free MEHP-D{sub 4}. The AUC of free MEHP-D{sub 4} normalized to DEHP-D{sub 4} dose and body weight (AUC/D) was 2.1 and 8.1 times, that of DEHP-D{sub 4} even 50 and 100 times higher than the corresponding AUC/D values obtained earlier in rat and marmoset, respectively. Time courses of the compounds in blood and urine of the volunteers oscillated widely. Terminal elimination half-lives were short (4.3–6.6 h). Total amounts of metabolites in 22-h urine are correlated linearly with the AUC of free MEHP-D{sub 4} in blood, the parameter regarded as relevant for risk assessment. -- Highlights: ► After DEHP intake, DEHP and MEHP in blood show oscillating time courses. ► Dose-related blood levels of DEHP are 50 times higher in humans than in rats. ► Dose-related blood levels of free MEHP are 2 times higher in humans than in rats. ► Elimination of DEHP and its metabolites is short with half-lives of 4.3-6.6 h.

  2. Coenzyme Q10 quantification in muscle, fibroblasts and cerebrospinal fluid by liquid chromatography/tandem mass spectrometry using a novel deuterated internal standard.

    Science.gov (United States)

    Duberley, Kate E C; Hargreaves, Iain P; Chaiwatanasirikul, Korn-Anong; Heales, Simon J R; Land, John M; Rahman, Shamima; Mills, Kevin; Eaton, Simon

    2013-05-15

    Neurological dysfunction is common in primary coenzyme Q10 (2,3-dimethoxy, 5-methyl, 6-polyisoprene parabenzoquinone; CoQ10 ; ubiquinone) deficiencies, the most readily treatable subgroup of mitochondrial disorders. Therapeutic benefit from CoQ10 supplementation has also been noted in other neurodegenerative diseases. CoQ10 can be measured by high-performance liquid chromatography (HPLC) in plasma, muscle or leucocytes; however, there is no reliable method to quantify CoQ10 in cerebrospinal fluid (CSF). Additionally, many methods use CoQ9 , an endogenous ubiquinone in humans, as an internal standard. Deuterated CoQ10 (d6 -CoQ10 ) was synthesised by a novel, simple, method. Total CoQ10 was measured by liquid chromatography/tandem mass spectrometry (LC/MS/MS) using d6 -CoQ10 as internal standard and 5 mM methylamine as an ion-pairing reagent. Chromatography was performed using a Hypsersil GOLD C4 column (150 × 3 mm, 3 µm). CoQ10 levels were linear over a concentration range of 0-200 nM (R(2) = 0.9995). The lower limit of detection was 2 nM. The inter-assay coefficient of variation (CV) was 3.6% (10 nM) and 4.3% (20 nM), and intra-assay CV 3.4% (10 nM) and 3.6% (20 nM). Reference ranges were established for CoQ10 in CSF (5.7-8.7 nM; n = 17), fibroblasts (57.0-121.6 pmol/mg; n = 50) and muscle (187.3-430.1 pmol/mg; n = 15). Use of d6 -CoQ10 internal standard has enabled the development of a sensitive LC/MS/MS method to accurately determine total CoQ10 levels. Clinical applications of CSF CoQ10 determination include identification of patients with cerebral CoQ10 deficiency, and monitoring CSF CoQ10 levels following supplementation. Copyright © 2013 John Wiley & Sons, Ltd.

  3. Preparation of deuterated succinic acids

    Energy Technology Data Exchange (ETDEWEB)

    Tashiro, Masashi; Tsuzuki, Hirohisa; Goto, Hideyuki; Ogasahara, Shoji; Mataka, Shuntaro (Kyushu Univ., Fukuoka (Japan)); Isobe, Shin-ichiro; Yonemitsu, Tadashi (Kyushu Sangyo Univ., Fukuoka (Japan). Dept. of Industrial Chemistry)

    1991-04-01

    Succinic (2,3-{sup 2}H{sub 2})- and (2,2,3,3-{sup 2}H{sub 4})-acids were prepared from maleic anhydride and dimethyl fumarate, and acetylene dicarboxylic acid and its dimethyl ester by treatment with Cu-Al and Ni-Al alloys in 10% NaOD-D{sub 2}0 in 95% to 100% isotopic purity. The succinic {sup 2}H{sub 4} acid having high isotopic purity was also obtained on the hydrolysis of 1,2-ethanedinitrile with alkaline deuterium oxide. Based on the {sup 1}H({sup 2}H) spectra analysis of N-(o-biphenyl)(2,3-{sup 2}H{sub 2})succinimide, it was elucidated that the Raney alloy reduction with alkaline deuterium oxide proceeds stepwise. (author).

  4. Infrared and Raman Spectra of Magnesium Ammonium Phosphate Hexahydrate (Struvite) and its Isomorphous Analogues. VIII. Spectra of Protiated and Partially Deuterated Magnesium Rubidium Phosphate Hexahydrate and Magnesium Thallium Phosphate Hexahydrate.

    Science.gov (United States)

    Soptrajanov, Bojan; Cahil, Adnan; Najdoski, Metodija; Koleva, Violeta; Stefov, Viktor

    2011-09-01

    The infrared and Raman spectra of magnesium rubidium phosphate hexahydrate MgRbPO4 • 6H2O and magnesium thallium phosphate hexahydrate, MgTlPO4 • 6H2O were recorded at room temperature (RT) and the boiling temperature of liquid nitrogen (LNT). To facilitate their analysis, also recorded were the spectra of partially deuterated analogues with varying content of deuterium. The effects of deuteration and those of lowering the temperature were the basis of the conclusions drawn regarding the origin of the observed bands which were assigned to vibrations which are predominantly localized in the water molecules (four crystallographically different types of such molecules exist in the structures) and those with PO43- character. It was concluded that in some cases coupling of phosphate and water vibrations is likely to take place. The appearance of the infrared spectra in the O-H stretching regions of the infrared spectra is explained as being the result of an extensive overlap of bands due to components of the fundamental stretching modes of the H2O units with a possible participation of bands due to second-order transitions. A broad band reminiscent of the B band of the well-known ABC trio characteristic of spectra of substances containing strong hydrogen bonds in their structure was found around 2400 cm-1 in the infrared spectra of the two studied compounds.

  5. Proton glass behaviour in a solid solution of gamma-irradiated deuterated betaine phosphate sub 0 sub . sub 1 sub 5 betaine phosphite sub 0 sub . sub 8 sub 5

    CERN Document Server

    Banys, J; Klimm, C; Voelkel, G; Kloepperpieper, A

    1997-01-01

    Measurements of the dielectric permittivity are reported for a deuterated solid solution of gamma-irradiated antiferroelectric (betainephosphate) sub 0 sub . sub 1 sub 5 ferroelectric (betainephosphite) sub 0 sub . sub 8 sub 5 at frequencies 20 H sub Z

  6. Structural refinement and extraction of hydrogen atomic positions in polyoxymethylene crystal based on the first successful measurements of 2-dimensional high-energy synchrotron X-ray diffraction and wide-angle neutron diffraction patterns of hydrogenated and deuterated species

    International Nuclear Information System (INIS)

    Tashiro, Kohji; Hanesaka, Makoto; Ohhara, Takashi; Kurihara, Kazuo; Tamada, Taro; Kuroki, Ryota; Fujiwara, Satoru; Ozeki, Tomoji; Kitano, Toshiaki; Nishu, Takashi; Tanaka, Ichiro; Niimura, Nobuo

    2007-01-01

    2-Dimensional X-ray and neutron diffraction patterns have been successfully measured for deuterated and hydrogenated polyoxymethylene (POM) samples obtained by γ-ray induced solid-state polymerization reaction. More than 700 reflections were collected from the X-ray diffraction data at -150degC by utilizing a high-energy synchrotron X-ray beam at SPring-8, Japan, from which the crystal structure of POM has been refined thoroughly including the extraction of hydrogen atomic positions at clearly seen in the difference Fourier synthesis map. As the first trial the nonuniform (9/5) helical model was analyzed with the reliability factor (R factor) 6.9%. The structural analysis was made also using the X-ray reflections of about 400 observed at room temperature (R 8.8%), and the thermal parameters of constituent atoms were compared between the low and high temperatures to discuss the librational thermal motion of the chains. The 2-dimensional neutron diffraction data, collected for the deuterated and hydrogenated POM samples using an imaging plate system specifically built-up for neutron scattering experiment, have allowed us to pick up the D and H atomic positions clearly in the Fourier synthesis maps. Another possible model, (29/16) helix, which was proposed by several researches, has been also investigated on the basis of the X-ray diffraction data at -150degC. The direct method succeeded in extracting this (29/16) model straightforwardly. The R factor was 8.6%, essentially the same as that of (9/5) helical model. This means that the comparison of the diffraction intensity between the data collected from the full-rotation X-ray diffraction pattern and the intensity calculated for both the (9/5) and (29/16) models cannot be used for the unique determination of the superiority of the model, (9/5) or (29/16) helix. However, we have found the existence of 001 and 002 reflections which give the longer repeating period 55.7 A. Besides there observed a series of meridional

  7. Correlation between the structure and infra-red absorption characteristics of mono-deuterated compounds: contribution to the study of organo-magnesium compounds; Correlations entre structure et absorption infrarouge de composes monodeuteries; contribution a l'etude des composes organomagnesiens

    Energy Technology Data Exchange (ETDEWEB)

    Paillous, A [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-10-01

    The high sensitivity of the {nu} (C-D) vibration to the variations brought about by the substitution of the carbon attached to the deuterium is shown in the case of organic or organo-metallic mono-deuterated molecules. In particular, syntheses of various mono-deuterated organo-magnesium compounds have been carried out; results are given concerning an infra-red spectrometric examination of these compounds in the range 2100 - 2250 cm{sup -1}. The results show the existence of only one type of deuterated carbon, which suggests that the same carbanion is involved in various ionic associations for the different magnesium-containing compounds. (authors) [French] La grande sensibilite de la vibration {nu} (C-D) aux variations apportees dans la substitution du carbone porteur du deuterium est mise en evidence pour des molecules organiques au organometalliques monodeuteriees. On a notamment realise la synthese de divers composes organomagnesiens monodeuteries; les observations auxquelles ils ont donne lieu en spectrometrie infrarouge, dons la zone 2100 - 2250 cm{sup -1}, sont rapportees; les resultats ne mettent en evidence qu'un seul type de carbone deuterie ce qui suggere I'intervention d'un meme carbanion dans des associations ioniques diverses pour les differents reactifs magnesiens. (auteur)

  8. Correlation between the structure and infra-red absorption characteristics of mono-deuterated compounds: contribution to the study of organo-magnesium compounds; Correlations entre structure et absorption infrarouge de composes monodeuteries; contribution a l'etude des composes organomagnesiens

    Energy Technology Data Exchange (ETDEWEB)

    Paillous, A. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1965-10-01

    The high sensitivity of the {nu} (C-D) vibration to the variations brought about by the substitution of the carbon attached to the deuterium is shown in the case of organic or organo-metallic mono-deuterated molecules. In particular, syntheses of various mono-deuterated organo-magnesium compounds have been carried out; results are given concerning an infra-red spectrometric examination of these compounds in the range 2100 - 2250 cm{sup -1}. The results show the existence of only one type of deuterated carbon, which suggests that the same carbanion is involved in various ionic associations for the different magnesium-containing compounds. (authors) [French] La grande sensibilite de la vibration {nu} (C-D) aux variations apportees dans la substitution du carbone porteur du deuterium est mise en evidence pour des molecules organiques au organometalliques monodeuteriees. On a notamment realise la synthese de divers composes organomagnesiens monodeuteries; les observations auxquelles ils ont donne lieu en spectrometrie infrarouge, dons la zone 2100 - 2250 cm{sup -1}, sont rapportees; les resultats ne mettent en evidence qu'un seul type de carbone deuterie ce qui suggere I'intervention d'un meme carbanion dans des associations ioniques diverses pour les differents reactifs magnesiens. (auteur)

  9. Dielectric properties in the vicinity of the ferroelectric phase transition in a mixed crystal of deuterated betaine phosphate{sub 0.03} betaine phosphite{sub 0.97}

    Energy Technology Data Exchange (ETDEWEB)

    Banys, J.; Macutkevic, J.; Kajokas, A.; Brilingas, A.; Grigas, J. [Faculty of Physics, Vilnius University, Sauletekio 9, Vilnius 2040 (Lithuania); Klimm, C.; Voelkel, G. [Fakultaet fuer Physik und Geowissenschaften, Universitaet Leipzig, Linnestr. 5, 04103 Leipzig (Germany)

    2004-02-01

    The dielectric behaviour of ferroelectric hydrogen bonded deuterated betaine phosphate{sub 0.03} betaine phosphite{sub 0.97} (DBP{sub 0.03}DBPI{sub 0.97})is investigated in the region of the ferroelectric phase transition. Dielectric dispersion is investigated in the frequency range up to 12 GHz. The dielectric dynamics shows a critical slowing down. The frequency of the relaxational soft mode in the paraelectric phase varies according to the quasi-one-dimensional Ising model and decreases up to 0.31 GHz at the phase transition temperature (T{sub C}=272 K). The obtained activation energy for the deuteron flipping motion {delta}U=2.3kT{sub C}=0.054 eV shows the order-disorder character of the ferroelectric phase transition. The spontaneous polarisation, obtained from pyroelectric measurements, is also well explained using the quasi-one-dimensional Ising model. At low temperatures, the freezing phenomena in DBP{sub 0.03}DBPI{sub 0.97} revealed the complex dielectric permittivity behaviour characteristic for the transition into the dipolar glass state. The activation energy of this low temperature process was found to be E{sub b}=1297 K (0.041 eV) and the glass temperature was estimated to 73 K. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Determining the mechanism of dehydration of primary, secondary, and tertiary alcohols by means of deuterium uptake on deuterated catalysts (BPO4, Ca3(PO4)2 and Sm2O3)

    International Nuclear Information System (INIS)

    Thomke, K.

    1977-01-01

    In order to gain insight into the mechanisms of dehydration (E1, E2, E1cB) of α- and β-substituted ethanols, the uptake of deuterium on deuterated catalysts [BPO 4 , Ca 3 (PO 4 ) 2 , Sm 2 O 3 ] into the alcohols and the thus formed olefines was measured. For that purpose microcatalytic and mass-spectrometric techniques were used. Most of the examined alcohols showed E1 on BPO 4 , E2 (sometimes mingled with E1) on Ca 3 (PO 4 ) 2 , and E1cB on Sm 2 O 3 . The common mechanism for ethanol on BPO 4 , for 2-propanol on Ca 3 (PO 4 ) 2 , and for 2-ethyl-2-propanol on Sm 2 O 3 was E2, i.e. that the OH-group and the β-proton were split off simultaneously. This can be explained by a decrease of the strength of the α-C-OH-bound caused by α-methyl-substitution on the one hand and by an increase of basicity of the catalyst on the other hand. (orig.) 891 HK [de

  11. Low-resolution structure of the tetrameric phenylalanyl-tRNA synthetase from Escherichia coli. A neutron small-angle scattering study of hybrids composed of protonated and deuterated protomers

    International Nuclear Information System (INIS)

    Dessen, P.; Ducruix, A.; May, R.P.; Blanquet, S.

    1990-01-01

    Escherichia coli phenylalanyl-tRNA synthetase is a tetrameric protein composed of two types of protomers. In order to resolve the subunit organization, neutron small-angle scattering experiments have been performed in different contrasts with all types of isotope hybrids that could be obtained by reconstituting the alpha 2 beta 2 enzyme from the protonated and deuterated forms of the alpha and beta subunits. Experiments have been also made with the isolated alpha promoter. A model for the alpha 2 beta 2 tetramer is deduced where the two alpha promoters are elongated ellipsoids (45 x 45 x 160 A3) lying side by side with an angle of about 40 degrees between their long axes and where the two beta subunits are also elongated ellipsoids (31 x 31 x 130 A3) with an angle of 30 degrees between their axes. This model was obtained by assuming that the two pairs of subunits are in contact in an orthogonal manner and by taking advantage of the measured distance between the centers of mass of the alpha 2 and beta 2 pairs (d = 23 +/- 2 A)

  12. {sup 15}N and {sup 13}C- SOFAST-HMQC editing enhances 3D-NOESY sensitivity in highly deuterated, selectively [{sup 1}H,{sup 13}C]-labeled proteins

    Energy Technology Data Exchange (ETDEWEB)

    Rossi, Paolo, E-mail: rossip@umn.edu; Xia, Youlin; Khanra, Nandish; Veglia, Gianluigi, E-mail: vegli001@umn.edu; Kalodimos, Charalampos G., E-mail: ckalodim@umn.edu [University of Minnesota, Department of Biochemistry, Molecular Biology and Biophysics (United States)

    2016-12-15

    The ongoing NMR method development effort strives for high quality multidimensional data with reduced collection time. Here, we apply ‘SOFAST-HMQC’ to frequency editing in 3D NOESY experiments and demonstrate the sensitivity benefits using highly deuterated and {sup 15}N, methyl labeled samples in H{sub 2}O. The experiments benefit from a combination of selective T{sub 1} relaxation (or L-optimized effect), from Ernst angle optimization and, in certain types of experiments, from using the mixing time for both NOE buildup and magnetization recovery. This effect enhances sensitivity by up to 2.4× at fast pulsing versus reference HMQC sequences of same overall length and water suppression characteristics. Representative experiments designed to address interesting protein NMR challenges are detailed. Editing capabilities are exploited with heteronuclear {sup 15}N,{sup 13}C-edited, or with diagonal-free {sup 13}C aromatic/methyl-resolved 3D-SOFAST-HMQC–NOESY–HMQC. The latter experiment is used here to elucidate the methyl-aromatic NOE network in the hydrophobic core of the 19 kDa FliT-FliJ flagellar protein complex. Incorporation of fast pulsing to reference experiments such as 3D-NOESY–HMQC boosts digital resolution, simplifies the process of NOE assignment and helps to automate protein structure determination.

  13. Report on the Sixth International Symposium on Isotopomers

    Energy Technology Data Exchange (ETDEWEB)

    Bao, H. [Louisiana State Univ., Baton Rouge, LA (United States); Farquhar, J. [Univ. of Maryland, College Park, MD (United States); Rumble, D. [Carnegie Inst. of Washington, Argonne, IL (United States). Geophysical Lab.

    2016-05-11

    The ISI 2012 met in Washington, DC, 18-22 June 2012, bringing together researchers and their students spanning an unusually wide range of disciplines including quantum and physical chemistry, cosmochemistry, atmospheric chemistry, chemical oceanography, biogeochemistry, organic and inorganic geochemistry. The diversity of subject matter was matched geographically with 92 attendees hailing from Canada, China, Finland, France, Germany, India, Israel, Japan, the Netherlands, Russia, Switzerland, Taiwan, the United Kingdom, and the USA. Although diverse, the group was united in its commitment to use the light stable isotopes of H, C, N, O, and S, with their equilibrium, kinetic, and intramolecular fractionations, to understand the material cycles and their dynamics between atmosphere, biosphere, hydrosphere, and lithosphere that make life possible on Earth. A distinct benefit of a small meeting like ISI 2012 is the opportunity for everyone to talk to each other. The historic rooms of the Carnegie Institution of Washington offered a cozy and warm atmosphere for participants in ISI 2012 to talk science and life in a casual, relaxed, and in-depth fashion. Graduate students and postdoctoral researchers were particularly appreciative of being able to spend five days together with old and new colleagues in comfortable quarters. Many commented that they had gained a lot more in building their life-long working relationships with colleagues at this meeting than at larger meetings.

  14. Simultaneous analysis of gemfibrozil, morphine, and its two active metabolites in different mouse brain structures using solid-phase extraction with ultra-high performance liquid chromatography and tandem mass spectrometry with a deuterated internal standard.

    Science.gov (United States)

    Yang, Zizhao; Wang, Lu; Xu, Mingcheng; Gu, Jingkai; Yu, Lushan; Zeng, Su

    2016-06-01

    A rapid and sensitive bioassay was established and validated to simultaneously determine gemfibrozil, morphine, morphine-3β-glucuronide, and morphine-6β-glucuronide in mouse cerebrum, epencephalon, and hippocampus based on ultra-high performance liquid chromatography and tandem mass spectrometry. The deuterated internal standard, M6G-d3, was mixed with the prepared samples at 10 ng/mL as the final concentration. The samples were transferred into the C18 solid-phase extraction columns with gradient elution for solid-phase extraction. The mobile phase consisted of methanol and 0.05% formic acid (pH 3.2). Multiple reaction monitoring has been applied to analyze gemfibrozil (m/z 249.0 → 121.0) in anion mode, and M6G-d3 (m/z 465.1 → 289.1), morphine (m/z 286.0 → 200.9), and M3G and M6G (m/z 462.1 → 286.1) in the positive ion mode. The method has a linear calibration range from 0.05 to 10 ng for gemfibrozil, morphine, and M3G and M6G with correlation coefficients >0.993. The lower limit of quantitation for all four analytes was 0.05 ng/mL, relative standard deviation of intra- and interday precision was less than 10.5%, and the relative error of accuracy was from -8.2 to 8.3% at low, medium, and high concentrations for all the analytes. In conclusion, gemfibrozil can influence the morphine antinociception after coronary heart disease induced chronic angina by the change in one of morphine metabolites', M3G, distribution in mouse brain. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Synthesis and reactions of deuterated 2-(alkylimino)-3-nitrosooxazolidines, 3-alkly-1-(2-hydroxyethyl)-1-nitrosoureas, and related compounds as possible intermediates in the aqueous decomposition of 3-alkyl-1-(2-chloroethyl)-1-nitrosoureas

    International Nuclear Information System (INIS)

    Lown, J.W.; Chauhan, S.M.S.

    1981-01-01

    Decomposition of 1-(2-chloroethyl)-3-cyclohexyl-1-nitrosourea-α-d 2 (CCNU-α-d 2 ) (7) in pH 7.2 phosphate buffer or of CINO-α-d 2 (9) or CHNU-α-d 2 (8) with the addition of chloride ion gives rise to the same spectrum of products, including deuterium-free acetaldehyde (29), a mixture of the two deuterio-2-chloroethanols, 2-hydroxy-2,2-dideuterioethyl cyclohexyl carbamates, and vinyl chloride containing one deuterium (i.e., opposite the results obtained in the corresponding reaction of BCNU-α-d 4 ). The products were identified and the number and position of the deuterium labels determined by GC/MS. The results are interpreted in terms of two decomposition pathways for CCNU. The first decomposition pathway operating for CCNU is via an intermediate-2-chloroethanediazohydroxide or the equivalent 2-chloroethyl cation in agreement with the results of other workers. The second pathway may involve reversible conversion of CCNU-α-d 2 (7) to CINO-α-d 2 (9) and then ring opening of the latter to CHNU-α-d 2 (8). Independent decomposition of 8 provides evidence for its conversion to a 1.1-dideuterio-2-hydroxyethanediazohydroxide (41) leading to the isolated carbamates 36 and 44. The intermediacy of species 41 may account for the formation of 2-hydroxyethylated nucleosides observed when (2-chloroethyl)nitrosoureas react with DNA. An alternative ring-opening reaction of 9 leads to a 2-hydroxydiazoethyl cyclohexylcarbamate species (37), elimination of which and attack by halide ion may account for the vinyl halide species formed. Further evidence in support of these competing pathways employing additional specifically deuterated intermediates is described and discussed

  16. Convenient synthesis of deuterated aluminium hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Pawelke, Roland H.; Felderhoff, Michael; Weidenthaler, Claudia [Max-Planck-Institut fuer Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Muelheim an der Ruhr (Germany); Schueth, Ferdi [Max-Planck-Institut fuer Kohlenforschung, Kaiser-Wilhelm-Platz 1, 45470 Muelheim an der Ruhr (Germany)], E-mail: schueth@mpi-muelheim.mpg.de

    2008-09-15

    We describe the ball-milling synthesis of alkali metal deuterides from commercial lithium aluminium deuteride. This reaction principle was exemplified by the mechanochemical synthesis of NaAlD{sub 4} and KAlD{sub 4}. NaAlD{sub 4} was prepared on the multi-gram scale by this procedure and purified by standard wet-chemical separation. Pure NaAlD{sub 4} was obtained and used for the synthesis of Ca(AlD{sub 4}){sub 2}. The formation of all products was verified by X-ray diffraction.

  17. Neutron scattering on partially deuterated polybutadiene

    CERN Document Server

    Kahle, S; Monkenbusch, M; Richter, D; Arbe, A; Colmenero, J; Frick, B

    2002-01-01

    The molecular nature of the secondary relaxation (Johari-Goldstein relaxation) and its relationship with the alpha relaxation is in most cases still unknown. In order to access these processes on a molecular level, it is necessary to obtain spatial information of the relaxation. Through the momentum-transfer dependence of the dynamic structure factor S(Q,t), this information can be provided by quasielastic neutron scattering techniques. The large difference in scattering lengths between hydrogen and deuterium allows us to accentuate specific correlations between atoms in a polymer melt. Here, we report on recent results on a polybutadiene melt, where the double bond was hydrogeneous, while the methylene groups carried deuterons (d4h2-PB). In this way the correlations between the double bonds are emphasised. We will show that the double bond/double bond correlation function, generated in this way, shows the same temperature dependence as the viscosity at higher temperatures at the structure factor peak maximum...

  18. Data acquisition system for a deuteration chamber

    International Nuclear Information System (INIS)

    Monroy A, L.

    1994-01-01

    The work present is focusing auxiliary in the experiment the reaction of fusion in cold in the laboratory of Physical of Plasmas of Instituto Nacional de Investigaciones Nucleares. These systems of acquisition of data concrete to register in line surface of pressure and temperature in the gap of 5.6 x 10 -4 to 1 x 10 3 and -270 to 1300 Centigrade degrees with help of personal computer. The manner of purchase in chamber of Deuterium is per middle of thermocouple with the object of whereas any control of the temperature in different point in the some of manner the signal of in for the system is the thermocouple (milli volts), the conversion analogy a digital is mean of Cad of 12 bits rate double slope the out is mean the PPI to send the signal to P C of these manner the read of the thermocouples is translate graphic or digital in the screen of the P C. In the phase of pressure element sensor is measure type Pirani, the measure is of manner of temperature. (Author)

  19. Tracing lipogenesis in humans using deuterated water

    International Nuclear Information System (INIS)

    Jones, P.J.H.

    1996-01-01

    Determination of quantitative de novo fat synthesis rates is important in our understanding of the role of nutritional factors in macronutient utilization and obesity development. To address these questions, we developed and applied a method for measuring lipogenesis using the uptake of deuterium enrichment in plasma very light density lipoprotein (VLDL) TGFA relative to the maximum as indicative of the fraction of VLDL-TGFA synthesized. Plateau enrichment was observed after 12 h of prime-constant oral deuterium oxide administration. Our initial studies applied this model in healthy humans consuming typical diets to demonstrate rates of TGFA synthesis amounting to 2 g·day -1 . In subsequent experiments it was shown that this level of synthesis was not affected by the frequency with which daily meals were consumed. Furthermore, in a clinical application, our results using this approach demonstrated that compared with normolipidemic controls, individuals with type III hyperlipoproteinemia displayed elevated TGFA but normal cholesterol synthesis rates. In summary, compared with other available methods for determination of lipogenesis, deuterium uptake is safe, direct, and inexpensive. Results suggest that under most dietary circumstances, human de novo lipogenesis is minor, thus dietary fat and carbohydrate balances remain largely independent. (author). 35 refs., 2 tabs., 4 figs

  20. Advances in the MQDT approach of electron/molecular cation reactive collisions: High precision extensive calculations for applications

    Directory of Open Access Journals (Sweden)

    Motapon O.

    2015-01-01

    Full Text Available Recent advances in the stepwise multichannel quantum defect theory approach of electron/molecular cation reactive collisions have been applied to perform computations of cross sections and rate coefficients for dissociative recombination and electron-impact ro-vibrational transitions of H2+, BeH+ and their deuterated isotopomers. At very low energy, rovibronic interactions play a significant role in the dynamics, whereas at high energy, the dissociative excitation strongly competes with all other reactive processes.

  1. Deuterium fractionation on interstellar grains studied with modified rate equations and a Monte Carlo approach

    Science.gov (United States)

    Caselli, Paola; Stantcheva, Tatiana; Shalabiea, Osama; Shematovich, Valery I.; Herbst, Eric

    2002-10-01

    The formation of singly and doubly deuterated isotopomers of formaldehyde and of singly, doubly, and multiply deuterated isotopomers of methanol on interstellar grain surfaces has been studied with a semi-empirical modified rate approach and a Monte Carlo method in the temperature range 10- 20 K. Agreement between the results of the two methods is satisfactory for all major and many minor species throughout this range. If gas-phase fractionation can produce a high abundance of atomic deuterium, which then accretes onto grain surfaces, diffusive surface chemistry can produce large abundances of deuterated species, especially at low temperatures and high gas densities. Warming temperatures will then permit these surface species to evaporate into the gas, where they will remain abundant for a considerable period. We calculate that the doubly deuterated molecules CHD 2OH and CH 2DOD are particularly abundant and should be searched for in the gas phase of protostellar sources. For example, at 10 K and high density, these species can achieve up to 10-20% of the abundance of methanol.

  2. Hydrogenation and Deuteration of C{sub 2}H{sub 2} and C{sub 2}H{sub 4} on Cold Grains: A Clue to the Formation Mechanism of C{sub 2}H{sub 6} with Astronomical Interest

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Hitomi; Kawakita, Hideyo [Koyama Astronomical Observatory, Kyoto Sangyo University Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555 (Japan); Hidaka, Hiroshi; Hama, Tetsuya; Watanabe, Naoki [Institute of Low Temperature Science, Hokkaido University N19-W8, Kita-ku, Sapporo, Hokkaido 060-0819 (Japan); Lamberts, Thanja; Kästner, Johannes, E-mail: h_kobayashi@kyoto-nijikoubou.com [Institute for Theoretical Chemistry, University of Stuttgart, Pfaffenwaldring 55, D-70569 Stuttgart (Germany)

    2017-03-10

    We quantitatively investigated the hydrogen addition reactions of acetylene (C{sub 2}H{sub 2}) and ethylene (C{sub 2}H{sub 4}) on amorphous solid water (ASW) at 10 and 20 K relevant to the formation of ethane (C{sub 2}H{sub 6}) on interstellar icy grains. We found that the ASW surface enhances the reaction rates for C{sub 2}H{sub 2} and C{sub 2}H{sub 4} by approximately a factor of 2 compared to those on the pure-solid C{sub 2}H{sub 2} and C{sub 2}H{sub 4} at 10 K, probably due to an increase in the sticking coefficient and adsorption energy of the H atoms on ASW. In contrast to the previous proposal that the hydrogenation rate of C{sub 2}H{sub 4} is orders of magnitude larger than that of C{sub 2}H{sub 2}, the present results show that the difference in hydrogenation rates of C{sub 2}H{sub 2} and C{sub 2}H{sub 4} is only within a factor of 3 on both the surfaces of pure solids and ASW. In addition, we found the small kinetic isotope effect for hydrogenation/deuteration of C{sub 2}H{sub 2} and C{sub 2}H{sub 4} at 10 K, despite the requirement of quantum tunneling. At 20 K, the reaction rate of deuteration becomes even larger than that of hydrogenation. These unusual isotope effects might originate from a slightly larger number density of D atoms than H atoms on ASW at 20 K. The hydrogenation of C{sub 2}H{sub 2} is four times faster than CO hydrogenation and can produce C{sub 2}H{sub 6} efficiently through C{sub 2}H{sub 4} even in the environment of a dark molecular cloud.

  3. Preparation of the Fv fragment from a short-chain mouse IgG2a anti-dansyl monoclonal antibody and use of selectively deuterated Fv analogues for two-dimensional 1H NMR analyses fo the antigen-antibody interactions

    International Nuclear Information System (INIS)

    Takahashi, Hideo; Igarashi, Takako; Shimada, Ichio; Arata, Yoji

    1991-01-01

    The Fv fragment, a univalent antigen-binding unit with a molecular weight of 25,000, has successfully been prepared in high yield by limited proteolysis with clostripain of a short-chain mouse IgG2a anti-dansyl monoclonal antibody in which the entire C H 1 domain is deleted. The Fv fragment obtained is stable at room temperature and retains its full antigen-binding capability. It has been shown that selective deuterium labeling of the Fv fragment, which is half the size of the Fab fragment, provides 1 H NMR spectral data at a sufficient resolution for a detailed structural analysis of the antigen-combining site. NOESY spectra of an Fv analogue, in which all aromatic protons except for His C2'-H and Tyr C3',5'-H had been deuterated, were measured in the presence of varying amounts of dansyl-L-lysine. On the basis of the NOESY data obtained, it was possible to assign all the ring proton resonances for the dansly group that is bound to the Fv fragment. It was also possible to obtain information about His and Tyr residues of the Fv fragment in the absence and presence of the antigen. On the basis of the NMR data obtained, the authors have shown that at least two Tyr residues along with one of the amide groups are directly involved in antigen binding. The mode of interaction of the dansyl ring with these residues in the Fv fragment has briefly been discussed

  4. Preparation of the Fv fragment from a short-chain mouse IgG2a anti-dansyl monoclonal antibody and use of selectively deuterated Fv analogues for two-dimensional sup 1 H NMR analyses fo the antigen-antibody interactions

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hideo; Igarashi, Takako; Shimada, Ichio; Arata, Yoji (Univ. of Tokyo (Japan))

    1991-03-19

    The Fv fragment, a univalent antigen-binding unit with a molecular weight of 25,000, has successfully been prepared in high yield by limited proteolysis with clostripain of a short-chain mouse IgG2a anti-dansyl monoclonal antibody in which the entire C{sub H}1 domain is deleted. The Fv fragment obtained is stable at room temperature and retains its full antigen-binding capability. It has been shown that selective deuterium labeling of the Fv fragment, which is half the size of the Fab fragment, provides {sup 1}H NMR spectral data at a sufficient resolution for a detailed structural analysis of the antigen-combining site. NOESY spectra of an Fv analogue, in which all aromatic protons except for His C2{prime}-H and Tyr C3{prime},5{prime}-H had been deuterated, were measured in the presence of varying amounts of dansyl-L-lysine. On the basis of the NOESY data obtained, it was possible to assign all the ring proton resonances for the dansly group that is bound to the Fv fragment. It was also possible to obtain information about His and Tyr residues of the Fv fragment in the absence and presence of the antigen. On the basis of the NMR data obtained, the authors have shown that at least two Tyr residues along with one of the amide groups are directly involved in antigen binding. The mode of interaction of the dansyl ring with these residues in the Fv fragment has briefly been discussed.

  5. CO and its Isotopomers Observation towards Sgr B2 L. L. Sun1, J. S. ...

    Indian Academy of Sciences (India)

    1991; Rodriguez-Fernandez & Combes 2008). Isotope ratios are considered to be a good tool to discriminate between gas flowing towards the disk and gas already residing in the disk of the central galactic plane. (Riquelme et al. 2010). A systematic study is performed on isotope abundance ratio of 18O to 17O of the ...

  6. A chemical probe for the estrogen receptor: synthesis of the 3H-isotopomer of raloxifene

    International Nuclear Information System (INIS)

    Dodge, J.A.; Stocksdale, M.G.; Jones, C.D.

    1995-01-01

    Radiolabelled raloxifene (LY 156758) has been prepared by tritium gas hydrogenolysis of a 3-aroyl-bis-brominated precursor. The requisite halogenated intermediate was accessed by regioselective aroylation of benzothiophene with the acid chloride of 3,5-dibromo-4-[2-(1-piperdinyl)ethoxy]benzoic acid. Selective deprotection of the aryl methyl ethers in the presence of the ethoxy side-chain followed by palladium catalyzed halogen-tritium exchange provided the target compound with a specific activity of 30.1 Ci/mmol. (author)

  7. Fundamental Study on the Separation of Methane Isotopomer by Cryogenic Distillation

    Energy Technology Data Exchange (ETDEWEB)

    Song, K.M.; Lee, S.K.; Kim, K.S.; Kim, W.S. [Korea Electric Power Research Institute, Taejon (Korea)

    2002-07-01

    For the purpose of {sup 13}CH{sub 4} production from LNG, the state art of the application of C-13 and the marketing research were investigated. The theoretical number of stages and the number of distillation column required for the separation of {sup 13}CH{sub 4} from {sup 12}CH{sub 4}/{sup 13}CH{sub 4} mixture containing 1%-{sup 13}CH{sub 4} are calculated. Assuming the ideal liquid mixture of {sup 12}CH{sub 4} and {sup 13}CH{sub 4}, the theoretical number of stages are calculated the minimum theorical number of stages are calculated by Smoker equation and FUG method. Using the correlation between the minimum theoretical number of stages and the optimum theoretical number of stages, the number of distillation groups is obtained. From the simulation, we postulate that 6 groups of distillation tower having 600 stages per one column are needed for the production of 90%-{sup 13}CH{sub 4}. (author). 18 refs., 33 figs., 9 tabs.

  8. Tritium and neutron measurements from deuterated Pd-Si

    International Nuclear Information System (INIS)

    Claytor, T.N.; Tuggle, D.G.; Menlove, H.O.; Seeger, P.A.; Doty, W.R.; Rohwer, R.K.

    1990-01-01

    Evidence has been found for tritium and neutron production in palladium and silicon stacks when pulsed with a high electric current. These palladium-silicon stacks consist of alternating layers of pressed palladium and silicon powder. A pulsed high electric current is thought to promote non equilibrium conditions important for tritium and neutron production. More than 2000 hours of neutron counting time has been accumulated in a underground, low background, environment with high efficiency counters (21%). Neutron emission has occurred as infrequent burst or as low level emission lasting for up to 20 hours. In eight of 30 cells, excess tritium greater than 3 sigma has been observed. In each of these measurements, with the powder system, the ratio of tritium detected to total integrated total neutrons inferred has been anomalously high. Recent cells have shown reproducible tritium generation at a level of about 0.5 nCi/hr. Several hydrogen and air control cells have been run with no anomalous excess tritium or neutron emission above background. A significant amount of the total palladium inventory (18%) has been checked for tritium contamination by three independent means. 12 refs., 6 figs., 2 tabs

  9. Magnetic behavior of cobalt bromide hydrates including a deuterated form

    Energy Technology Data Exchange (ETDEWEB)

    DeFotis, G.C., E-mail: gxdefo@wm.edu; Hampton, A.S.; Van Dongen, M.J.; Komatsu, C.H.; DeSanto, C.L.; Davis, C.M.

    2017-04-15

    The magnetic properties of little examined CoBr{sub 2}• 2H{sub 2}O and new CoBr{sub 2}• H{sub 2}O and CoBr{sub 2}• D{sub 2}O are studied. Curie-Weiss fits, χ{sub M}=C/(T-θ), yield θ of −9.9, 9.4 and 10.0 K, respectively, over a 30–80 K linear range for each. Higher temperature data are fit assuming two moderately separated low lying Kramers doublets, with exchange accounted for in a mean-field approximation. Susceptibility maxima appear at 9.5, 15.4 and 15.5 K, with χ{sub max} of 0.163, 0.375 and 0.435 emu/mol, respectively. Antiferromagnetic ordering is estimated to occur at 9.0, 13.7 and 13.8 K, in the same order. The ratio T{sub c}/T{sub max} is 0.95, 0.89 and 0.89, respectively, suggesting little low dimensional magnetic character in singly hydrated systems. Data at lower temperatures for the dihydrate are fit with an antiferromagnetic 3D-Ising model. For singly hydrated systems the large size of χ{sub max} prevents this; weakened interchain antiferromagnetic interactions yield enhanced susceptibility maxima. Magnetization data exhibit field induced transitions near 13.5 kG for the dihydrate, and near 6.5 kG for singly hydrated systems with enhanced hysteresis. These transitions are interpreted as metamagnetic in nature. - Highlights: • CoBr{sub 2}• 2H{sub 2}O has a larger susceptibility maximum at lower temperature than CoCl{sub 2}• 2H{sub 2}O. • Enhanced antiferromagnetic susceptibility maxima occur in CoBr{sub 2}·H{sub 2}O and CoBr{sub 2}• D{sub 2}O. • Metamagnetic transitions occur at much lower fields in monohydrates than dehydrate. • Interchain antiferromagnetic exchange is weaker in monohydrates than dehydrate. • CoBr{sub 2}• H{sub 2}O exhibit spin glass behavior similar to that seen previously in CoCl{sub 2}·H{sub 2}O.

  10. Photoredox-catalyzed deuteration and tritiation of pharmaceutical compounds.

    Science.gov (United States)

    Loh, Yong Yao; Nagao, Kazunori; Hoover, Andrew J; Hesk, David; Rivera, Nelo R; Colletti, Steven L; Davies, Ian W; MacMillan, David W C

    2017-12-01

    Deuterium- and tritium-labeled pharmaceutical compounds are pivotal diagnostic tools in drug discovery research, providing vital information about the biological fate of drugs and drug metabolites. Herein we demonstrate that a photoredox-mediated hydrogen atom transfer protocol can efficiently and selectively install deuterium (D) and tritium (T) at α-amino sp 3 carbon-hydrogen bonds in a single step, using isotopically labeled water (D 2 O or T 2 O) as the source of hydrogen isotope. In this context, we also report a convenient synthesis of T 2 O from T 2 , providing access to high-specific-activity T 2 O. This protocol has been successfully applied to the high incorporation of deuterium and tritium in 18 drug molecules, which meet the requirements for use in ligand-binding assays and absorption, distribution, metabolism, and excretion studies. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  11. Soft mode and acoustic mode ferroelectric properties of deuterated ...

    Indian Academy of Sciences (India)

    1973) applied molecular field approximation in tunneling model for same crystal system. And Blinc et al. (1961) applied pseudospin model to triglycine group crystal. Much later, Chaudhuri et al (1988) applied Mitsui's (1958) model (which was ...

  12. Biomolecular-solvent stereodynamic coupling probed by deuteration

    International Nuclear Information System (INIS)

    Fornili, S.L.; Leone, M.; Madonia, F.; Migliore, M.; Palma-Vittorelli, M.B.; Palma, M.U.; San Biagio, P.L.

    1983-01-01

    Thermodynamic interpretation of experiments with isotopically perturbed solvent supports the view that solvent stereodynamics is directly relevant to thermodynamic stability of biomolecules. According with the current understanding of the structure of the aqueous solvent, in any stereodynamic configuration of the latter, connectivity pathways are identifiable for their topologic and order properties. Perturbing the solvent by isotopic substitution or, e.g., by addition of co-solvents, can therefore be viewed as reinforcing or otherwise perturbing these topologic structures. This microscopic model readily visualizes thermodynamic interpretation. In conclusion, the topologic stereodynamic structures of connectivity pathways in the solvent, as modified by interaction with solutes, acquire a specific thermodynamic and biological significance, and the problem of thermodynamic and functional stability of biomolecules is seen in its full pertinent phase space

  13. Dispersion of low frequency vibrations in the deuterated naphthalene crystal

    International Nuclear Information System (INIS)

    Bokhenkov, E.L.; Sheka, E.; Natkaniec, I.

    1977-01-01

    The dispersion curves of the lattice vibrations and of the two lowest intramolecular vibrations in d 8 -naphthalene (C 10 D 8 ) crystal have been measured by coherent inelastic neutron scattering for the [010] and the [100] directions at the temperature of 98 K and partially at 5 K. The results are compared with calculations based on the Kitaigorodskii parameters for C-C, C-H and H-H interactions in organic molecular crystals. (author)

  14. Chemical synthesis of deuterated folate monoglutamate and in vivo assessment of urinary excretion of deuterated folates in man

    International Nuclear Information System (INIS)

    Gregory, J.F. III; Toth, J.P.

    1988-01-01

    The synthesis and in vivo application of stable-isotopically labeled folic acid was investigated to devise methods suitable for studies of folate metabolism in human subjects. Glutamate-labeled tetradeutero-pteroylglutamic acid (d4-folic acid) was prepared by mixed anhydride coupling of N10-trifluoroacetylpteroic acid and dimethyl L-[3,3,4,4-2H4]glutamic acid, saponification in sodium deuteroxide, and chromatographic purification. Retention of the isotopic label was verified by proton NMR and mass spectrometry of the para-aminobenzoylglutamic acid product of C9-N10 bond cleavage. A method was devised for determination of of isotopic enrichment of urinary d4-folates derived from orally administered d4-folic acid using affinity chromatographic purification, chemical cleavage of the C9-N10 bond, HPLC isolation of the p-[2H4]aminobenzoylglutamate product, followed by negative-ion chemical-ionization gas chromatography/mass spectrometry. Data concerning the urinary excretion of d4-folates derived from an oral dose of d4-folic acid in an adult human are presented

  15. The cyclopropene radical cation: Rovibrational level structure at low energies from high-resolution photoelectron spectra

    Energy Technology Data Exchange (ETDEWEB)

    Vasilatou, K.; Michaud, J. M.; Baykusheva, D.; Grassi, G.; Merkt, F. [Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093 Zurich (Switzerland)

    2014-08-14

    The cyclopropene radical cation (c-C{sub 3}H{sub 4}{sup +}) is an important but poorly characterized three-membered-ring hydrocarbon. We report on a measurement of the high-resolution photoelectron and photoionization spectra of cyclopropene and several deuterated isotopomers, from which we have determined the rovibrational energy level structure of the X{sup ~+} {sup 2}B{sub 2} ground electronic state of c-C{sub 3}H{sub 4}{sup +} at low energies for the first time. The synthesis of the partially deuterated isotopomers always resulted in mixtures of several isotopomers, differing in their number of D atoms and in the location of these atoms, so that the photoelectron spectra of deuterated samples are superpositions of the spectra of several isotopomers. The rotationally resolved spectra indicate a C{sub 2v}-symmetric R{sub 0} structure for the ground electronic state of c-C{sub 3}H{sub 4}{sup +}. Two vibrational modes of c-C{sub 3}H{sub 4}{sup +} are found to have vibrational wave numbers below 300 cm{sup −1}, which is surprising for such a small cyclic hydrocarbon. The analysis of the isotopic shifts of the vibrational levels enabled the assignment of the lowest-frequency mode (fundamental wave number of ≈110 cm{sup −1} in c-C{sub 3}H{sub 4}{sup +}) to the CH{sub 2} torsional mode (ν{sub 8}{sup +}, A{sub 2} symmetry) and of the second-lowest-frequency mode (≈210 cm{sup −1} in c-C{sub 3}H{sub 4}{sup +}) to a mode combining a CH out-of-plane with a CH{sub 2} rocking motion (ν{sub 15}{sup +}, B{sub 2} symmetry). The potential energy along the CH{sub 2} torsional coordinate is flat near the equilibrium structure and leads to a pronounced anharmonicity.

  16. Quantitative profiling of PE, MMPE, DMPE, and PC lipid species by multiple precursor ion scanning: A tool for monitoring PE metabolism

    DEFF Research Database (Denmark)

    Bilgin, Mesut; Markgraf, Daniel F; Duchoslav, Eva

    2011-01-01

    We report a method for the simultaneous identification and quantification of phosphatidylethanolamine (PE), monomethyl-phosphatidylethanolamine (MMPE), dimethyl-phosphatidylethanolamine (DMPE), and phosphatidylcholine (PC) species in lipid extracts. The method employs a specific "mass-tag" strategy...... where DMPE, MMPE, and PE species are chemically methylated with deuterated methyliodide (CD(3)I) to produce PC molecules having class-specific mass offsets of 3, 6 and 9Da, respectively. The derivatized aminoglycerophospholipids release characteristic phosphorylcholine-like fragment ions having specific...... and DMPE, and abundant PE and PC species in a single mass spectrometric analysis. We demonstrated the efficacy of the methodology by conducting a series of biochemical experiments using stable isotope labeled ethanolamine to survey the activities and substrate specificities of enzymes involved in PE...

  17. Effects of an oral insulin nanoparticle administration on hepatic glucose metabolism assessed by 13C and 2H isotopomer analysis

    NARCIS (Netherlands)

    Reis, C.P.; Neufeld, R.; Veiga, F.; Figueiredo, I.V.; Jones, J.; Soares, A.F.; Nunes, P.M.; Damg\\'e, C.; Carvalho, R.A.

    2012-01-01

    The purpose of this study was to evaluate hepatic glucose metabolism of diabetic induced rats after a daily oral load of insulin nanoparticles over 2 weeks. After the 2-week treatment, an oral glucose tolerance test was performed with [U-��C] glucose and �H2O. Plasma glucose �H and ��C enrichments

  18. Closed-loop 15N measurement of N2O and its isotopomers for real-time greenhouse gas tracing

    Science.gov (United States)

    Slaets, Johanna; Mayr, Leopold; Heiling, Maria; Zaman, Mohammad; Resch, Christian; Weltin, Georg; Gruber, Roman; Dercon, Gerd

    2016-04-01

    Quantifying sources of nitrous oxide is essential to improve understanding of the global N cycle and to develop climate-smart agriculture, as N2O has a global warming potential 300 times higher than CO2. The isotopic signature and the intramolecular distribution (site preference) of 15N are powerful tools to trace N2O, but the application of these methods is limited as conventional methods cannot provide continuous and in situ data. Here we present a method for closed-loop, real time monitoring of the N2O flux, the isotopic signature and the intramolecular distribution of 15N by using off-axis integrated cavity output spectroscopy (ICOS, Los Gatos Research). The developed method was applied to a fertilizer inhibitor experiment, in which N2O emissions were measured on undisturbed soil cores for three weeks. The treatments consisted of enriched urea-N (100 kg urea-N/ha), the same fertilizer combined with the nitrification inhibitor nitrapyrin (375 g/100 kg urea), and control cores. Monitoring the isotopic signature makes it possible to distinguish emissions from soil and fertilizer. Characterization of site preference could additionally provide a tool to identify different microbial processes leading to N2O emissions. Furthermore, the closed-loop approach enables direct measurement on site and does not require removal of CO2 and H2O. Results showed that 75% of total N2O emissions (total=11 346 μg N2O-N/m2) in the fertilized cores originated from fertilizer, while only 55% of total emissions (total=2 450 μg N2ON/m2) stemmed from fertilizer for the cores treated with nitrapyrin. In the controls, N2O derived from soil was only 40% of the size of the corresponding pool from the fertilized cores, pointing towards a priming effect on the microbial community from the fertilizer and demonstrating the bias that could be introduced by relying on non-treated cores to estimate soil emission rates, rather than using the isotopic signature. The site preference increased linearly over time for the cores with fertilizer and those with nitrapyrin, but the increase was stronger for the fertilized cores: during the first 10 days of the experiment, theses cores showed a more negative site preference than the cores with inhibitor, while during the last 10 days, the site preference for the fertilized cores was more positive than that of the inhibitor. This change indicates that the site preference of 15N can be used to distinguish the processes of nitrification and denitrification, the former having been supressed by nitrapyrin in the cores treated with the inhibitor. Low enrichment levels (5% atomic excess in this study) sufficed in order to separate emissions from soil and fertilizer, making the proposed closed-loop approach a cost-effective and practical tool to obtain a continuous, in situ characterization of N2O sources.

  19. N2O isotopomers and N2:N2O ratio as indicators of denitrification in ecosystems

    International Nuclear Information System (INIS)

    Mander, Ülo; Zaman, Mohammad

    2015-01-01

    The world is experiencing climate change and variability due to increased greenhouse gas (GHG) emissions. The main GHG’s of concern are nitrous oxide (N 2 O), carbon dioxide (CO 2 ) and methane (CH 4 ). Agriculture contributes approximately 14% of the world’s GHG emissions. Nitrous oxide is one of the key GHG and ozone (O 3 ) depleting gas, constituting 7% of the anthropogenic greenhouse effect. On a molecular basis, N 2 O has a 310- and 16-fold greater global warming potential than each of CO 2 and CH 4 , respectively, over a 100-year period. Nitrous oxide can be produced through both chemical and biochemical pathways. They occur during denitrification (the stepwise conversion of nitrate (NO 3 - ) to nitrogen gas (N 2 ) and during nitrification by ammonia-oxidizing archea (bacteria) during the oxidation of hydroxylamine (NH 2 OH) to nitrite (NO 2 - ) which is then reduced to N 2 O and N 2 by nitrifier denitrification or heterotrophic denitrification

  20. A chiral synthesis of dapoxetine hydrochloride, a serotonin re-uptake inhibitor, and its 14C isotopomer

    International Nuclear Information System (INIS)

    Wheeler, W.J.; O'Bannon, D.D.

    1992-01-01

    The 14 C-isotopmer of dapoxetine-[ 14 C] HCl (S (+) -N,N-dimethyl-α[2-(1-naphthalenyloxy)ethyl-2- 14 C]benzenemeth a-n amine hydrochloride, 1a), a potent serotonin re-uptake inhibitor has been prepared by a chiral synthesis, starting with tert. -butyloxyphenylglycine (3). Borane reduction, followed by activation of the resulting alcohol 4 as its mesylate 5b, provided the chiral starting material. The radiolabel was introduced by reaction of 5b with sodium cyanide-[ 14 C]. The desired product (1) was then elaborated from nitrile 6a,b via a five step synthesis in an overall 19.5% radiochemical yield. (Author)

  1. Effects of a glucokinase activator on hepatic intermediary metabolism: study with 13C-isotopomer-based metabolomics

    OpenAIRE

    Nissim, Itzhak; Horyn, Oksana; Nissim, Ilana; Daikhin, Yevgeny; Wehrli, Suzanne L.; Yudkoff, Marc; Matschinsky, Franz M.

    2012-01-01

    GKAs (glucokinase activators) are promising agents for the therapy of Type 2 diabetes, but little is known about their effects on hepatic intermediary metabolism. We monitored the fate of 13C-labelled glucose in both a liver perfusion system and isolated hepatocytes. MS and NMR spectroscopy were deployed to measure isotopic enrichment. The results demonstrate that the stimulation of glycolysis by GKA led to numerous changes in hepatic metabolism: (i) augmented flux through the TCA (tricarboxy...

  2. Experimental and theoretical studies of the reaction of the OH radical with alkyl sulfides: 1. Direct observations of the formation of the OH-DMS adduct-pressure dependence of the forward rate of addition and development of a predictive expression at low temperature.

    Science.gov (United States)

    Williams, M B; Campuzano-Jost, P; Cossairt, B M; Hynes, A J; Pounds, A J

    2007-01-11

    the range 238-245 K, allowing the formulation of an expression which can be used to calculate the effective rate coefficient for reaction 1 at any pressure and oxygen concentration. The expression can calculate the effective rate coefficient for reaction 1 to +/- 40% over the range 220-260 K, with the largest errors at the extremes of this range. Gaussian 03 has been used to calculate the structure of the OH-DMS adduct and its deuterated isotopomer. We find similar bound structures for both isotopomers. The calculated enthalpies of formation of the adducts are lower than the experimentally determined values.

  3. Spectroscopy of H3+: planets, chaos and the Universe

    International Nuclear Information System (INIS)

    Tennyson, J.

    1995-01-01

    This review discusses the H 3 + molecular ion and its deuterated isotopomers. The ion is important because of its fundamental nature, astrophysical significance and dynamical richness. The following topics are discussed: the discovery of H 3 + , its unusual bonding and the important role played by ab initio electronic-structure calculations; the formation of H 3 + and its importance in models of the interstellar medium; the unusual spectroscopy of H 3 + and the accurate quantum calculations which led to laboratory observations; the failure to detect H 3 + in the interstellar medium and its accidental observation in Jupiter; work on H 3 + in the giant planets and other astronomical emission spectra; the very unusual infrared photodissociation spectrum of H 3 + ; and the classical and quantal behaviour of the molecule at its dissociation limit. (author)

  4. Implausibility of the vibrational theory of olfaction.

    Science.gov (United States)

    Block, Eric; Jang, Seogjoo; Matsunami, Hiroaki; Sekharan, Sivakumar; Dethier, Bérénice; Ertem, Mehmed Z; Gundala, Sivaji; Pan, Yi; Li, Shengju; Li, Zhen; Lodge, Stephene N; Ozbil, Mehmet; Jiang, Huihong; Penalba, Sonia F; Batista, Victor S; Zhuang, Hanyi

    2015-05-26

    The vibrational theory of olfaction assumes that electron transfer occurs across odorants at the active sites of odorant receptors (ORs), serving as a sensitive measure of odorant vibrational frequencies, ultimately leading to olfactory perception. A previous study reported that human subjects differentiated hydrogen/deuterium isotopomers (isomers with isotopic atoms) of the musk compound cyclopentadecanone as evidence supporting the theory. Here, we find no evidence for such differentiation at the molecular level. In fact, we find that the human musk-recognizing receptor, OR5AN1, identified using a heterologous OR expression system and robustly responding to cyclopentadecanone and muscone, fails to distinguish isotopomers of these compounds in vitro. Furthermore, the mouse (methylthio)methanethiol-recognizing receptor, MOR244-3, as well as other selected human and mouse ORs, responded similarly to normal, deuterated, and (13)C isotopomers of their respective ligands, paralleling our results with the musk receptor OR5AN1. These findings suggest that the proposed vibration theory does not apply to the human musk receptor OR5AN1, mouse thiol receptor MOR244-3, or other ORs examined. Also, contrary to the vibration theory predictions, muscone-d30 lacks the 1,380- to 1,550-cm(-1) IR bands claimed to be essential for musk odor. Furthermore, our theoretical analysis shows that the proposed electron transfer mechanism of the vibrational frequencies of odorants could be easily suppressed by quantum effects of nonodorant molecular vibrational modes. These and other concerns about electron transfer at ORs, together with our extensive experimental data, argue against the plausibility of the vibration theory.

  5. Neutron measurements in deuterated palladium cathodes subjected to pulsed electrolytic currents

    International Nuclear Information System (INIS)

    Granada, J.R.; Mayer, R.E.; Guido, G.; Florido, P.C.; Patino, N.E.; Gillette, V.H.; Sobehart, L.; Gomez, S.; Larreteguy, A.; Universidad Nacional de Cuyo, San Carlos de Bariloche

    1989-01-01

    We report on neutron measurements performed on electrolytic cells using a high efficiency (22%) detection system in combination with a procedure involving a non-stationary current through the cell's circuit. Under these conditions, neutron production was observed in cells containing LiH dissolved in heavy water with a Palladium cathode. Characteristic patterns showing one or two bumps were obtained in a repeatable fashion, depending on the previous charging history of the cathode. (orig.)

  6. Synthesis of selectively deuterated and tritiated lupane derivatives with cytotoxic activity

    Czech Academy of Sciences Publication Activity Database

    Vlk, M.; Urban, M.; Elbert, Tomáš; Šarek, J.

    2013-01-01

    Roč. 298, č. 2 (2013), s. 1149-1157 ISSN 0236-5731 Grant - others:GA ČR(CZ) GA305/09/1216 Institutional support: RVO:61388963 Keywords : isotopic labelling * tritium * deuterium * betulin * betulinic acid * cytotoxicity Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.415, year: 2013

  7. Probing self assembly in biological mixed colloids by SANS, deuteration and molecular manipulation

    Energy Technology Data Exchange (ETDEWEB)

    Hjelm, R.P. [Los Alamos National Laboratory, NM (United States); Thiyagarajan, P. [Argonne National Laboratory, IL (United States); Hoffman, A. [Univ. of California, San Diego, CA (United States); Alkan-Onyuksel, H. [Univ. of Illinois, Chicago, IL (United States)

    1994-12-31

    Small-angle neutron scattering was used to obtain information on the form and molecular arrangement of particles in mixed colloids of bile salts with phosphatidylcholine, and bile salts with monoolein. Both types of systems showed the same general characteristics. The particle form was highly dependent on total lipid concentration. At the highest concentrations the particles were globular mixed micelles with an overall size of 50{Angstrom}. As the concentration was reduced the mixed micelles elongated, becoming rodlike with diameter about 50{Angstrom}. The rods had a radial core-shell structure in which the phosphatidylcholine or monoolein fatty tails were arranged radially to form the core with the headgroups pointing outward to form the shell. The bile salts were at the interface between the shell and core with the hydrophilic parts facing outward as part of the shell. The lengths of the rods increased and became more polydispersed with dilution. At sufficiently low concentrations the mixed micelles transformed into single bilayer vesicles. These results give insight on the physiological function of bile and on the rules governing the self assembly of bile particles in the hepatic duct and the small intestine.

  8. NMR relaxation and phase transitions in solid methane and deuterated derivatives

    International Nuclear Information System (INIS)

    Putten, D. van der.

    1984-01-01

    This thesis describes an investigation of properties of solid methane at high pressure (till 10 kbar) with temperatures ranging from 2 until 100 K. The high inverse moment of inertia of the molecule combined with low ordering potentials gives rise to properties for which quantum effects play an important role: e.g. the transition temperature to a partially ordered phase shows an isotope effect of 35% when CH 4 protons are substituted by deuterons. Interpretation of NMR properties of solid methane also show quantum effects. First, a helium cryostat is developed and described and NMR results for CH 4 , CH 2 D 2 and CD 4 are given. The influence of discrete tunnel states on the spin-lattice relaxation is studied theoretically. Application of group theory has simplified the calculations considerably. (G.J.P.)

  9. Stereoselective semi-hydrogenation and deuteration of a diacetylenic precursor of leukotriene B4 methyl ester

    International Nuclear Information System (INIS)

    Pontikis, R.; Le Merrer, Y.; Depezay, J.-C.; Petillot, Y.; Rousseau, B.; Beaucourt, J.P.

    1990-01-01

    [6,7,14,15- 2 H4]-Leukotriene B4 methyl ester was prepared by reduction with deuterium gas of a suitable precursor (deuterium incorporation > 90%). Several catalytic semi-hydrogenations were affected in order to determine the best conditions for the labeling step. (author)

  10. A Low Temperature Infrared Study Of Deuterated NH4VO3

    Science.gov (United States)

    de Waal, D.; Heyns, A. M.

    1989-12-01

    The existence of (NH4)2V6016 as an intermediate in the thermal decomposition of NH4V03 to V205 has been confirmed by vibrational spectroscopy, resulting in the following reaction in an open systeml: NH4VO3 1 bar, air, 50-200°C/(1) (NH4)2v6o16 1 bar, air, ca.360°C/(2) V205 The kinetics of reaction (1) was studied by means of Raman spectroscopy, and structural information on NH4V03 and (N114)V60 16 was required to obtain an accurate description of the reaction mechanism2. Information on the site symmetry of an ammonium ion and hydrogen bonding in a crystal can be obtained by considering the infrared spectra of isotopically dilute NH3D+ ions in the lattice at liquid nitrogen temperatures3, especially as the position of hydrogen atoms in (NHO2V6016 could not be determined by X-ray methods.

  11. Plasma cholesterol synthesis using deuterated water in humans: effect of short-term food restriction

    International Nuclear Information System (INIS)

    Jones, P.J.; Scanu, A.M.; Schoeller, D.A.

    1988-01-01

    Our purpose was to develop methods in humans to determine the fractional synthetic rate (FSR) of plasma pool free cholesterol using the rate of deuterium incorporation from body water. The sensitivity of this method was examined by measuring FSR after periods of fasting and feeding. Five healthy men with normal lipoprotein levels were given a prepared diet containing 40% of calories as fat and a polyunsaturated/saturated fatty acid ratio of 0.25 for 8 days, except for day 7 when they were given only drinking water. Beginning after the supper meal on day 6, they received no food until 8 AM on day 8 when they consumed meals as normal. Over days 7 and 8 the subjects were given prime and constant deuterium oxide orally to maintain body water deuterium enrichment at about 0.05 atom % excess. Plasma samples were obtained at 0 hours (day 7, 8 AM) and at 12, 24, 36, and 48 hours thereafter. Free cholesterol was extracted, purified by thin-layer chromatography, and combusted to water. The water was reduced to H 2 and analyzed for deuterium enrichment by isotope ratio mass spectrometry. Analytic precision of this system was determined as 3.5 0/00 (parts per mil) vs Standard Mean Ocean Water. Deuterium enrichment of plasma water for the group during the 48-hour deuterium oxide administration period was 3143 0/00 +/- 310 0/00 (mean +/- SEM). Cholesterol deuterium enrichment for the group during the 12-hour period of fasting (10.9 0/00 +/- 4.1 0/00) was not different from that during feeding (14.2 0/00 +/- 6.2 0/00)

  12. Measurement of gluconeogenesis by deuterated water: the effect of equilibration time and fasting period

    NARCIS (Netherlands)

    Allick, Gideon; van der Crabben, Saskia N.; Ackermans, Mariette T.; Endert, Erik; Sauerwein, Hans P.

    2006-01-01

    Fasting gluconeogenesis (GNG) is often quantified using the 2H2O technique, which is based on plasma 2H2O enrichment and ensuing enrichment of plasma glucose at the C5 and C2 positions. Fractional (fr)GNG can be calculated using the ratio of C5 to C2 enrichment or the ratio of C5 to plasma 2H2O

  13. Normal and Inverse Diffusive Isotope Fractionation of Deuterated Toluene and Benzene in Aqueous Systems

    DEFF Research Database (Denmark)

    Rolle, Massimo; Jin, Biao

    2017-01-01

    Diffusive isotope fractionation of organic contaminants in aqueous solution is difficult to quantify, and only a few experimental data sets are available for compounds of environmental interest. In this study, we investigate diffusive fractionation of perdeuterated and nondeuterated benzene...... and toluene. Multitracer experiments were carried out in 1-D gel dissection tubes and in a quasi-2-D flow-through porous medium. The experiments allowed us to simultaneously and directly compare the diffusive and dispersive behavior of benzene and toluene. We observed an unexpected, opposite behavior...... of the two monoaromatic hydrocarbons. Toluene showed a normal diffusive isotope effect (DC7D8/DC7H8 = 0.96) with enrichment of the nondeuterated isotopologue in the direction of the diffusive and transverse dispersive fluxes. Conversely, the measured trends for benzene indicate inverse diffusive...

  14. Stereospecific synthesis of specifically deuterated metoprolol enantiomers from chiral starting materials

    Energy Technology Data Exchange (ETDEWEB)

    Shetty, H.U.; Murthy, S.S.; Nelson, W.L. (Washington Univ., Seattle, WA (USA). Dept. of Medicinal Chemistry)

    1989-10-01

    Enantiomers of metoprolol (1) containing six deuterium atoms in the isopropyl methyl groups ((2R)), two deuterium atoms at C-2 and C-6 of the aromatic ring ((2S)), and two deuterium atoms at C-3 of the propanolamine side chain ((2S)) were prepared. Chiral 2,2-dimethyl-1,3-dioxolane-4-methanols ((4R) and (4S)) were key synthons. Sources of deuterium were ({sup 2}H{sub 6})-isopropyl-amine, 4-(2-methoxyethyl)-2,6-({sup 2}H{sub 2})-phenol, prepared by {sup 2}HCl/{sup 2}H{sub 2}O exchange, and (4S)-2,2-dimethyl-1,3-dioxolane-4-({sup 2}H{sub 2})-4-methanol, prepared by LiAl{sup 2}H{sub 4} reduction of (4S)-methyl 2,2-dimethyl-1,3-dioxolane-4-carboxylate. Enantiomeric excess was greater than 94% for each of the prepared enantiomers, as determined independently by {sup 1}H NMR spectroscopy on diastereomeric derivatives and by chiral column HPLC. (author).

  15. Normal and Inverse Diffusive Isotope Fractionation of Deuterated Toluene and Benzene in Aqueous Systems

    DEFF Research Database (Denmark)

    Rolle, Massimo; Jin, Biao

    2017-01-01

    and toluene. Multitracer experiments were carried out in 1-D gel dissection tubes and in a quasi-2-D flow-through porous medium. The experiments allowed us to simultaneously and directly compare the diffusive and dispersive behavior of benzene and toluene. We observed an unexpected, opposite behavior...... of the two monoaromatic hydrocarbons. Toluene showed a normal diffusive isotope effect (DC7D8/DC7H8 = 0.96) with enrichment of the nondeuterated isotopologue in the direction of the diffusive and transverse dispersive fluxes. Conversely, the measured trends for benzene indicate inverse diffusive...

  16. Thermal neutron measurements on electrolytic cells with deuterated palladium cathodes subjected to a pulsed current

    International Nuclear Information System (INIS)

    Granada, J.R.; Mayer, R.E.; Guido, G.; Florido, P.C.; Larreteguy, A.; Gillette, V.H.; Patino, N.E.; Converti, J.; Gomez, S.E.

    1990-01-01

    The present work describes the design of a high efficiency thermal neutron detection system and the measurements performed with it on electrolytic cells containing LiH dissolved in D 2 O with palladium cathodes. A procedure involving the use of a non-stationary (pulsed) current through the cell caused a correlated neutron production to be observed in a repeatable manner. These patterns are strongly dependent on the previous charging history of the cathodes. The technique employed seems to be very useful as a research tool for a systematic study of the different variables governing the phenomenon. (author)

  17. Triple nuclear reactions (d, n) in laser-generated plasma from deuterated targets

    Czech Academy of Sciences Publication Activity Database

    Torrisi, L.; Cutroneo, Mariapompea

    2017-01-01

    Roč. 24, č. 6 (2017), č. článku 063102. ISSN 1070-664X R&D Projects: GA ČR(CZ) GBP108/12/G108; GA MŠk LM2015056 Institutional support: RVO:61389005 Keywords : ion acceleration * pulsed laser * polyethylene Subject RIV: BL - Plasma and Gas Discharge Physics OBOR OECD: Fluids and plasma physics (including surface physics) Impact factor: 2.115, year: 2016

  18. Electron transport in liquids: effect of unbalancing the methane molecule by deuteration

    International Nuclear Information System (INIS)

    Floriano, M.A.; Freeman, G.R.

    1983-01-01

    The mobility of electrons in nonpolar liquids is strongly dependent on the molecular shape. In spherelike methane the mobility is three orders of magnitude greater than in the rodlike ethane. To investigate the enormous gap between methane and ethane, the effect of slightly perturbing the symmetry of the methane molecule by progressive deuterium substitution was studied. At temperatures near the triple point (T/Tsub(c) approximately 0.48) and near the mobility maximum (T/Tsub(c) approximately 0.93) the mobilities change in the order: CH 4 > CH 3 D > CH 2 D 2 3 approximately CD 4 . The differences are related to the symmetries of the molecules and to the rotational motions. (Authors)

  19. Ion source parameters and hydrogen scrambling in the ECD of selectively deuterated peptides

    DEFF Research Database (Denmark)

    Duchateau, Magalie; Jørgensen, Thomas J. D.; Robine, Ophélie

    2014-01-01

    (the ability to obtain deuterium levels of individual residues). An essential prerequisite for this approach is that the level of hydrogen scrambling is negligible. The occurrence of hydrogen scrambling depends critically on the extent of vibrational excitation in the mass spectrometer. In particular......, the desolvation process in the electrospray ion source is likely to induce scrambling at standard operating conditions. Consequently, finding experimental conditions that minimize hydrogen scrambling to a negligible level is thus pivotal for the application of electron-based fragmentation in HDX-MS/MS experiments...

  20. An investigation of phase transitions in solid methane and deuterated derivatives to pressures of 3 kbar

    International Nuclear Information System (INIS)

    Sprik, M.

    1982-01-01

    The first part of this thesis is an experimental investigation of the interaction responsible for the I-II transition and the second part comprises three theoretical studies of several of the properties of phase I and II. The first chapter of part I, is a general introduction to a thermodynamic treatment of the isotope effect in an orientational phase transition. The thermodynamic approach yields a corresponding state model for the phase diagrams of the five isotopes of methane (CH 4 , CHD 3 , CH 2 D 2 , CH 3 D and CD 4 ). In the remaining two chapters of part I, the corresponding state relation mentioned above is applied to the I-II transition of methane in order to obtain an experimental value for the effective exponent n of the dependence on intermolecular separation of the ordering anisotropic interaction. Part II starts with a derivation of a quasi-classical approximation to the statistical density matrix of a free spherical top. While the orientational system is treated classically, the consequences of the other characteristic of the methane molecules are considered, i.e. the high approximately odd symmetry of the molecule (the octupole field in phase II is odd under spatial inversion). It is argued that the renormalization group analysis of critical phenomena in certain highly complicated antiferromagnetic systems may be equally well applied to the I-II transition in methane. Finally, the study of the quantum effect in phase II is resumed. The spin lattice relaxation time at very low temperature is calculated from first principles using an orientational dynamical process of purely quantum-mechanical nature. (Auth.)

  1. Neutron emission generated during wire array Z-pinch implosion onto deuterated fiber

    Czech Academy of Sciences Publication Activity Database

    Klir, D.; Kravarik, J.; Kubes, P.; Rezac, K.; Ananev, S.S.; Bakshaev, Yu. L.; Blinov, P. I.; Chernenko, A. S.; Kazakov, E.D.; Korolev, V. D.; Meshcherov, B.R.; Ustroev, G. I.; Juha, Libor; Krása, Josef; Velyhan, Andriy

    2008-01-01

    Roč. 15, č. 3 (2008), 32701/1-32701/13 ISSN 1070-664X R&D Projects: GA MŠk(CZ) LC528; GA MŠk LA08024 Institutional research plan: CEZ:AV0Z10100523 Keywords : fusion plasmas * d-d reaction * neutron yield * Z pinch * high-current discharges Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 2.427, year: 2008

  2. Erosion behavior of soft, amorphous deuterated carbon films by heat treatment in air and under vacuum

    International Nuclear Information System (INIS)

    Maruyama, K.

    1999-01-01

    The erosion of soft a-C:D films by heat treatment in air and under vacuum is studied by ion-beam analysis. When the films are heated in air above 500 K, the film thickness and the areal densities of C and especially D decrease, and oxygen is incorporated in the films. The initial atomic loss rates of carbon and deuterium from the films are 2.6 x 10 17 C atoms cm -2 h -1 and 4.8 x 10 17 D atoms cm -2 h -1 at 550 K. However, after D depletion the films show a resistivity against further erosion due to annealing in air. When the films are heated under vacuum erosion starts at about 600 K and all components including D decrease proportionally to the film thickness. Thermal desorption spectroscopy of the films reveals the evolution of C x D y type hydrocarbons. Infrared analysis shows that the incorporated oxygen is chemically bonded to carbon. The thermally-activated decomposition of the soft a-C:D films is compared to that of hard a-C:D films and a reaction scheme is suggested. (orig.)

  3. Probing self assembly in biological mixed colloids by SANS, deuteration and molecular manipulation

    International Nuclear Information System (INIS)

    Hjelm, R.P.; Thiyagarajan, P.; Hoffman, A.; Alkan-Onyuksel, H.

    1994-01-01

    Small-angle neutron scattering was used to obtain information on the form and molecular arrangement of particles in mixed colloids of bile salts with phosphatidylcholine, and bile salts with monoolein. Both types of systems showed the same general characteristics. The particle form was highly dependent on total lipid concentration. At the highest concentrations the particles were globular mixed micelles with an overall size of 50 Angstrom. As the concentration was reduced the mixed micelles elongated, becoming rodlike with diameter about 50 Angstrom. The rods had a radial core-shell structure in which the phosphatidylcholine or monoolein fatty tails were arranged radially to form the core with the headgroups pointing outward to form the shell. The bile salts were at the interface between the shell and core with the hydrophilic parts facing outward as part of the shell. The lengths of the rods increased and became more polydispersed with dilution. At sufficiently low concentrations the mixed micelles transformed into single bilayer vesicles. These results give insight on the physiological function of bile and on the rules governing the self assembly of bile particles in the hepatic duct and the small intestine

  4. Production and X-ray crystallographic analysis of fully deuterated human carbonic anhydrase II

    Energy Technology Data Exchange (ETDEWEB)

    Budayova-Spano, Monika [European Molecular Biology Laboratory Grenoble Outstation, 6 Rue Jules Horowitz, 38042 Grenoble (France); Institut Laue-Langevin, 6 Rue Jules Horowitz, BP 156, 38042 Grenoble (France); Fisher, S. Zoë [Department of Biochemistry and Molecular Biology, PO Box 100245, University of Florida, Gainesville, FL 32610 (United States); Dauvergne, Marie-Thérèse [European Molecular Biology Laboratory Grenoble Outstation, 6 Rue Jules Horowitz, 38042 Grenoble (France); Agbandje-McKenna, Mavis [Department of Biochemistry and Molecular Biology, PO Box 100245, University of Florida, Gainesville, FL 32610 (United States); Silverman, David N. [Department of Pharmacology and Therapeutics, PO Box 100267, University of Florida, Gainesville, FL 32610 (United States); Myles, Dean A. A. [European Molecular Biology Laboratory Grenoble Outstation, 6 Rue Jules Horowitz, 38042 Grenoble (France); Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831 (United States); McKenna, Robert, E-mail: rmckenna@ufl.edu [Department of Biochemistry and Molecular Biology, PO Box 100245, University of Florida, Gainesville, FL 32610 (United States); European Molecular Biology Laboratory Grenoble Outstation, 6 Rue Jules Horowitz, 38042 Grenoble (France)

    2006-01-01

    This article reports the production, crystallization and X-ray structure determination of perdeuterated human carbonic anhydrase (HCA II). The refined structure is shown to be highly isomorphous with hydrogenated HCA II, especially with regard to the active site architecture and solvent network. Human carbonic anhydrase II (HCA II) is a zinc metalloenzyme that catalyzes the reversible hydration and dehydration of carbon dioxide and bicarbonate, respectively. The rate-limiting step in catalysis is the intramolecular transfer of a proton between the zinc-bound solvent (H{sub 2}O/OH{sup −}) and the proton-shuttling residue His64. This distance (∼7.5 Å) is spanned by a well defined active-site solvent network stabilized by amino-acid side chains (Tyr7, Asn62, Asn67, Thr199 and Thr200). Despite the availability of high-resolution (∼1.0 Å) X-ray crystal structures of HCA II, there is currently no definitive information available on the positions and orientations of the H atoms of the solvent network or active-site amino acids and their ionization states. In preparation for neutron diffraction studies to elucidate this hydrogen-bonding network, perdeuterated HCA II has been expressed, purified, crystallized and its X-ray structure determined to 1.5 Å resolution. The refined structure is highly isomorphous with hydrogenated HCA II, especially with regard to the active-site architecture and solvent network. This work demonstrates the suitability of these crystals for neutron macromolecular crystallography.

  5. Fourier transform infrared difference spectroscopy of bacteriorhodopsin and its photoproducts regenerated with deuterated tyrosine

    International Nuclear Information System (INIS)

    Dollinger, G.; Eisenstein, L.; Lin, S.L.; Nakanishi, K.; Termini, J.

    1986-01-01

    Fourier transform infrared (FTIR) difference spectroscopy has been used to detect the vibrational modes due to tyrosine residues in the protein that change in position or intensity between light-adapted bacteriorhodopsin (LA) and other species, namely, the K and M intermediates and dark-adapted bacteriorhodopsin (DA). To aid in the identification of the bands that change in these various species, the FTIR spectra of the free amino acids Tyr-d0, Tyr-d2 ( 2 H at positions ortho to OH), and Tyr-d4 ( 2 H at positions ortho and meta to OH) were measured in H 2 O and D 2 O at low and high pH. The characteristic frequencies of the Tyr species obtained in this manner were then used to identify the changes in protonation state of the tyrosine residues in the various bacteriorhodopsin species. The two diagnostically most useful bands were the approximately 1480-cm-1 band of Tyr(OH)-d2 and the approximately 1277-cm-1 band of Tyr(O-)-d0. Mainly by observing the appearance or disappearance of these bands in the difference spectra of pigments incorporating the tyrosine isotopes, it was possible to identify the following: in LA, one tyrosine and one tyrosinate; in the K intermediate, two tyrosines; in the M intermediate, one tyrosine and one tyrosinate; and in DA, two tyrosines. Since these residues were observed in the difference spectra K/LA, M/LA, and DA/LA, they represent the tyrosine or tyrosinate groups that most likely undergo changes in protonation state due to the conversions. These changes are most likely linked to the proton translocation process of bacteriorhodopsin

  6. Physiologically Based Simulations of Deuterated Glucose for Quantifying Cell Turnover in Humans

    Directory of Open Access Journals (Sweden)

    Christoph Niederalt

    2017-04-01

    Full Text Available In vivo [6,6-2H2]-glucose labeling is a state-of-the-art technique for quantifying cell proliferation and cell disappearance in humans. However, there are discrepancies between estimates of T cell proliferation reported in short (1-day versus long (7-day 2H2-glucose studies and very-long (9-week 2H2O studies. It has been suggested that these discrepancies arise from underestimation of true glucose exposure from intermittent blood sampling in the 1-day study. Label availability in glucose studies is normally approximated by a “square pulse” (Sq pulse. Since the body glucose pool is small and turns over rapidly, the availability of labeled glucose can be subject to large fluctuations and the Sq pulse approximation may be very inaccurate. Here, we model the pharmacokinetics of exogenous labeled glucose using a physiologically based pharmacokinetic (PBPK model to assess the impact of a more complete description of label availability as a function of time on estimates of CD4+ and CD8+ T cell proliferation and disappearance. The model enabled us to predict the exposure to labeled glucose during the fasting and de-labeling phases, to capture the fluctuations of labeled glucose availability caused by the intake of food or high-glucose beverages, and to recalculate the proliferation and death rates of immune cells. The PBPK model was used to reanalyze experimental data from three previously published studies using different labeling protocols. Although using the PBPK enrichment profile decreased the 1-day proliferation estimates by about 4 and 7% for CD4 and CD8+ T cells, respectively, differences with the 7-day and 9-week studies remained significant. We conclude that the approximations underlying the “square pulse” approach—recently suggested as the most plausible hypothesis—only explain a component of the discrepancy in published T cell proliferation rate estimates.

  7. ATMOS Stratospheric Deuterated Water and Implications for Tropospheric-Stratospheric Transport

    Science.gov (United States)

    Moyer, Elisabeth J.; Irion, Fredrick W.; Yung, Yuk L.; Gunson, Michael R.

    1996-01-01

    Measurements of the isotopic composition of stratospheric water by the ATMOS instrument are used to infer the convective history of stratospheric air. The average water vapor entering the stratosphere is found to be highly depleted of deuterium, with delta-D(sub w) of -670 +/- 80 (67% deuterium loss). Model calculations predict, however, that under conditions of thermodynamic equilibrium, dehydration to stratospheric mixing ratios should produce stronger depletion to delta-D(sub w) of -800 to 900 (80-90% deuterium loss). Deuterium enrichment of water vapor in ascending parcels can occur only in conditions of rapid convection; enrichments persisting into the stratosphere require that those conditions continue to near-tropopause altitudes. We conclude that either the predominant source of water vapor to the uppermost troposphere is enriched convective water, most likely evaporated cloud ice, or troposphere-stratosphere transport occurs closely associated with tropical deep convection.

  8. The kinetics of the photochemical reaction cycle of deuterated bacteriorhodopsin and pharaonis halorhodopsin

    International Nuclear Information System (INIS)

    Szakacs, Julianna; Lakatos, Melinda; Varo, Gy.; Ganea, Constanta

    2005-01-01

    Kinetic isotope effects in the photochemical reaction cycle of bacteriorhodopsin and pharaonis halorhodopsin were determined in H 2 O and D 2 O at normal pH, to get insight in the proton dependent steps of the transport process. All the steps of the bacteriorhodopsin photocycle at normal pH exhibited a strong isotope effect. In the case of halorhodopsin in both the chloride and nitrate transporting conditions the photocycle was not strongly affected by the deuterium exchange. In the case of chloride, a slight slow down of the photocycle could be observed. On the opposite, in the nitrate transport conditions a reverse effect is present. (author)

  9. Synthesis and positron emission tomography studies of C-11-labeled isotopomers and metabolites of GTS-21, a partial {alpha}7 nicotinic cholinergic agonist drug

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sung Won [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States) and Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400 (United States)]. E-mail: swkim@bnl.gov; Ding Yushin [Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400 (United States); Department of Radiology, Yale University School of Medicine, New Haven, CT 06520-8048 (United States); Alexoff, David [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Patel, Vinal [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Logan, Jean [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Lin, K.-S. [Department of Radiology, University of Pittsburgh, Pittsburgh, PA 15213 (United States); Shea, Colleen [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Muench, Lisa [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Xu Youwen [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Carter, Pauline [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); King, Payton [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Constanzo, Jasmine R. [Department of Chemistry, Fordham University, Bronx, NY 10458 (United States); Ciaccio, James A. [Department of Chemistry, Fordham University, Bronx, NY 10458 (United States); Fowler, Joanna S. [Medical Department, Brookhaven National Laboratory, Upton, NY 11973 (United States); Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400 (United States); Department of Psychiatry, Mount Sinai School of Medicine, New York, NY 10029 (United States)

    2007-07-15

    Introduction: (3E)-3-[(2,4-dimethoxyphenyl)methylene]-3,4,5,6-tetrahydro-2,3'-bipyridine (GTS-21), a partial {alpha}7 nicotinic acetylcholine receptor agonist drug, has recently been shown to improve cognition in schizophrenia and Alzheimer's disease. One of its two major demethylated metabolites, 4-OH-GTS-21, has been suggested to contribute to its therapeutic effects. Methods: We labeled GTS-21 in two different positions with carbon-11 ([2-methoxy-{sup 11}C]GTS-21 and [4-{sup 11}C]GTS-21) along with two corresponding demethylated metabolites ([2-methoxy-{sup 11}C]4-OH-GTS-21 and [4-methoxy-{sup 11}C]2-OH-GTS-21) for pharmacokinetic studies in baboons and mice with positron emission tomography (PET). Results: Both [2-{sup 11}C]GTS-21 and [4-methoxy-{sup 11}C]GTS-21 showed similar initial high rapid uptake in baboon brain, peaking from 1 to 3.5 min (0.027-0.038%ID/cc) followed by rapid clearance (t {sub 1/2}<15 min), resulting in low brain retention by 30 min. However, after 30 min, [2-methoxy-{sup 11}C]GTS-21 continued to clear while [4-methoxy-{sup 11}C]GTS-21 plateaued, suggesting the entry of a labeled metabolite into the brain. Comparison of the pharmacokinetics of the two labeled metabolites confirmed expected higher brain uptake and retention of [4-methoxy-{sup 11}C]2-OH-GTS-21 (the labeled metabolite of [4-methoxy-{sup 11}C]GTS-21) relative to [2-methoxy-{sup 11}C]4-OH-GTS-21 (the labeled metabolite of [2-methoxy-{sup 11}C]GTS-21), which had negligible brain uptake. Ex vivo studies in mice showed that GTS-21 is the major chemical form in the mouse brain. Whole-body dynamic PET imaging in baboon and mouse showed that the major route of excretion of C-11 is through the gallbladder. Conclusions: The major findings are as follows: (a) extremely rapid uptake and clearance of [2-methoxy-{sup 11}C]GTS-21 from the brain, which may need to be considered in developing optimal dosing of GTS-21 for patients, and (b) significant brain uptake of 2-OH-GTS-21, suggesting that it might contribute to the therapeutic effects of GTS-21. This study illustrates the value of comparing different label positions and labeled metabolites to gain insight on the behavior of a central nervous system drug and its metabolites in the brain, providing an important perspective on drug pharmacokinetics.

  10. Synthesis and positron emission tomography studies of C-11-labeled isotopomers and metabolites of GTS-21, a partial α7 nicotinic cholinergic agonist drug

    International Nuclear Information System (INIS)

    Kim, Sung Won; Ding Yushin; Alexoff, David; Patel, Vinal; Logan, Jean; Lin, K.-S.; Shea, Colleen; Muench, Lisa; Xu Youwen; Carter, Pauline; King, Payton; Constanzo, Jasmine R.; Ciaccio, James A.; Fowler, Joanna S.

    2007-01-01

    Introduction: (3E)-3-[(2,4-dimethoxyphenyl)methylene]-3,4,5,6-tetrahydro-2,3'-bipyridine (GTS-21), a partial α7 nicotinic acetylcholine receptor agonist drug, has recently been shown to improve cognition in schizophrenia and Alzheimer's disease. One of its two major demethylated metabolites, 4-OH-GTS-21, has been suggested to contribute to its therapeutic effects. Methods: We labeled GTS-21 in two different positions with carbon-11 ([2-methoxy- 11 C]GTS-21 and [4- 11 C]GTS-21) along with two corresponding demethylated metabolites ([2-methoxy- 11 C]4-OH-GTS-21 and [4-methoxy- 11 C]2-OH-GTS-21) for pharmacokinetic studies in baboons and mice with positron emission tomography (PET). Results: Both [2- 11 C]GTS-21 and [4-methoxy- 11 C]GTS-21 showed similar initial high rapid uptake in baboon brain, peaking from 1 to 3.5 min (0.027-0.038%ID/cc) followed by rapid clearance (t 1/2 11 C]GTS-21 continued to clear while [4-methoxy- 11 C]GTS-21 plateaued, suggesting the entry of a labeled metabolite into the brain. Comparison of the pharmacokinetics of the two labeled metabolites confirmed expected higher brain uptake and retention of [4-methoxy- 11 C]2-OH-GTS-21 (the labeled metabolite of [4-methoxy- 11 C]GTS-21) relative to [2-methoxy- 11 C]4-OH-GTS-21 (the labeled metabolite of [2-methoxy- 11 C]GTS-21), which had negligible brain uptake. Ex vivo studies in mice showed that GTS-21 is the major chemical form in the mouse brain. Whole-body dynamic PET imaging in baboon and mouse showed that the major route of excretion of C-11 is through the gallbladder. Conclusions: The major findings are as follows: (a) extremely rapid uptake and clearance of [2-methoxy- 11 C]GTS-21 from the brain, which may need to be considered in developing optimal dosing of GTS-21 for patients, and (b) significant brain uptake of 2-OH-GTS-21, suggesting that it might contribute to the therapeutic effects of GTS-21. This study illustrates the value of comparing different label positions and labeled metabolites to gain insight on the behavior of a central nervous system drug and its metabolites in the brain, providing an important perspective on drug pharmacokinetics

  11. Isotopomer profiling of Leishmania mexicana promastigotes reveals important roles for succinate fermentation and aspartate uptake in tricarboxylic acid cycle (TCA) anaplerosis, glutamate synthesis, and growth.

    Science.gov (United States)

    Saunders, Eleanor C; Ng, William W; Chambers, Jennifer M; Ng, Milica; Naderer, Thomas; Krömer, Jens O; Likic, Vladimir A; McConville, Malcolm J

    2011-08-05

    Leishmania parasites proliferate within nutritionally complex niches in their sandfly vector and mammalian hosts. However, the extent to which these parasites utilize different carbon sources remains poorly defined. In this study, we have followed the incorporation of various (13)C-labeled carbon sources into the intracellular and secreted metabolites of Leishmania mexicana promastigotes using gas chromatography-mass spectrometry and (13)C NMR. [U-(13)C]Glucose was rapidly incorporated into intermediates in glycolysis, the pentose phosphate pathway, and the cytoplasmic carbohydrate reserve material, mannogen. Enzymes involved in the upper glycolytic pathway are sequestered within glycosomes, and the ATP and NAD(+) consumed by these reactions were primarily regenerated by the fermentation of phosphoenolpyruvate to succinate (glycosomal succinate fermentation). The initiating enzyme in this pathway, phosphoenolpyruvate carboxykinase, was exclusively localized to the glycosome. Although some of the glycosomal succinate was secreted, most of the C4 dicarboxylic acids generated during succinate fermentation were further catabolized in the TCA cycle. A high rate of TCA cycle anaplerosis was further suggested by measurement of [U-(13)C]aspartate and [U-(13)C]alanine uptake and catabolism. TCA cycle anaplerosis is apparently needed to sustain glutamate production under standard culture conditions. Specifically, inhibition of mitochondrial aconitase with sodium fluoroacetate resulted in the rapid depletion of intracellular glutamate pools and growth arrest. Addition of high concentrations of exogenous glutamate alleviated this growth arrest. These findings suggest that glycosomal and mitochondrial metabolism in Leishmania promastigotes is tightly coupled and that, in contrast to the situation in some other trypanosomatid parasites, the TCA cycle has crucial anabolic functions.

  12. Protocol development for continuous nitrogen-15 measurement of N2O and its isotopomers for real-time greenhouse gas tracing

    International Nuclear Information System (INIS)

    Slaets, J.; Mayr, L.; Heiling, M.; Zaman, M.; Resch, C.; Weltin, G.; Gruber, R.; Dercon, G.

    2016-01-01

    Quantifying sources of nitrous oxide (N2O) (soil-N and applied N) is essential to improve our understanding of the global N cycle and to develop climate-smart agriculture, as N 2 O has a global warming potential that is 300 times higher than that of CO 2 . The isotopic signature and the intramolecular distribution (site preference) of 15 N are powerful tools to identify N 2 O sources. We have developed a protocol for continuous (closedloop), real time measurement of the N 2 O flux, the isotopic signature and the intramolecular distribution of 15 N by using off-axis integrated cavity output spectroscopy (ICOS, Los Gatos Research). The method was applied in a fertilizer inhibitor experiment, in which N 2 O emissions were measured on undisturbed soil cores for three weeks. The treatments consisted of enriched 15 N labelled urea (5 atom %) applied at a rate equivalent to 100 kg N/ha), 15 N labelled urea with the nitrification inhibitor (NI) nitrapyrin (375 g/100 kg urea), and controls (no fertilizer or NI).

  13. Low Mass MS/MS Fragments of Protonated Amino Acids Used for Distinction of Their 13C- Isotopomers in Metabolic Studies

    Science.gov (United States)

    Ma, Xin; Dagan, Shai; Somogyi, Árpád; Wysocki, Vicki H.; Scaraffia, Patricia Y.

    2013-04-01

    Glu, Gln, Pro, and Ala are the main amino acids involved in ammonia detoxification in mosquitoes. In order to develop a tandem mass spectrometry method (MS2) to monitor each carbon of the above isotopically-labeled 13C-amino acids for metabolic studies, the compositions and origins of atoms in fragments of the protonated amino acid should be first elucidated. Thus, various electrospray (ESI)-based MS2 tools were employed to study the fragmentation of these unlabeled and isotopically-labeled amino acids and better understand their dissociation pathways. A broad range of fragments, including previously-undescribed low m/z fragments was revealed. The formulae of the fragments (from m/z 130 down to m/z 27) were confirmed by their accurate masses. The structures and conformations of the larger fragments of Glu were also explored by ion mobility mass spectrometry (IM-MS) and gas-phase hydrogen/deuterium exchange (HDX) experiments. It was found that some low m/z fragments ( m/z 27-30) are common to Glu, Gln, Pro, and Ala. The origins of carbons in these small fragments are discussed and additional collision induced dissociation (CID) MS2 fragmentation pathways are proposed for them. It was also found that small fragments (≤ m/z 84) of protonated, methylated Glu, and methylated Gln are the same as those of the underivatized Glu and Gln. Taken together, the new approach of utilizing low m/z fragments can be applied to distinguish, identify, and quantify 13C-amino acids labeled at various positions, either in the backbone or side chain.

  14. Deuterium exchange rate between D3+ and organic CH bonds: Implication for D enrichment in meteoritic IOM

    Science.gov (United States)

    Robert, François; Derenne, Sylvie; Thomen, Aurélien; Anquetil, Christelle; Hassouni, Khaled

    2011-12-01

    The rate of the transfer of deuterium from D3+ to the three types (benzylic, aliphatic and aromatic) of bonds of 2-Ethylnaphthalene (and Methylnaphthalene) has been measured in the laboratory. The D/H ratio of each bond was calculated from the mass spectrum of the different isotopomers produced in the source of the GC mass spectrometer. The relations between the D/H ratio of the different isotopomers allow to calculate the internal isotopic fractionation factors ( αi- j = (D/H) i/(D/H) j) between the 3 bonds: αBenzylic-Aromatic = 1.99 ± 0.38 and αAliphatic-Aromatic = 1.22 ± 0.39. Isotopic exchange rate constants are ⩾2.2 × 10 -7±0.4 s -1, determined at room temperature for 10 -3 g of 2-Ethylnaphthalene in contact with 5 × 10 12 cm -3 of D3+. These results are compatible with those measured in the insoluble organic matter (IOM) isolated from the Orgueil meteorite ( Remusat et al., 2006), i.e., αBenzylic-Aromatic = 1.96 ± 0.05 and αAliphatic-Aromatic = 1.35 ± 0.05. Using the calculated dust and H 2D + densities from the models of deuterium chemistry in protostellar disks, the duration needed to enrich the IOM up to its measured D/H ratio is ⩽10 4±1 s. These laboratory results are in agreement with a late deuteration of the insoluble organic matter taking place in the solar T-Tauri disk by interaction of the organic dust with H 2D +.

  15. Spectroscopic and Quantum Mechanical Calculation Study of the Effect of Isotopic Substitution on NIR Spectra of Methanol.

    Science.gov (United States)

    Grabska, Justyna; Czarnecki, Mirosław A; Beć, Krzysztof B; Ozaki, Yukihiro

    2017-10-19

    In this work, we studied methanol and its deuterated derivatives (CH 3 OH, CH 3 OD, CD 3 OH, CD 3 OD) by NIR spectroscopy and anharmonic quantum chemical calculations. Vibrational bands corresponding to up to three quanta transitions (first and second overtones, binary and ternary combination modes) were predicted by the use of the VPT2 route. The accuracy of prediction of NIR modes was evaluated through density functional theory (DFT) with selected density functionals and basis sets. On the basis of the theoretical NIR spectra, detailed band assignments for all studied molecules were proposed. It was found that the pattern of bands in NIR spectra of deuterated methanols can be used for identification of isotopically equalized forms. Calculations of NIR spectra of all possible forms of CXXXOX (X = H, D) molecules demonstrated that the isotopic contamination can be identified due to a coexistence of bands specific to OH and OD groups. Also, bands from partially deuterated methyl groups can be distinguished in NIR spectra. Since the VPT2 framework is known to be sensitive to inaccuracy in the case of highly anharmonic modes, we obtained an independent insight by numerical solving of the time-independent Schrödinger equation corresponding to the O-X stretching mode scanned within -0.4 to 2.0 Å over a dense grid of 0.005 Å. This way the energies of vibrational levels of the CX1X2X3OX4 (X = H, D) isotopomers and the corresponding transition frequencies were obtained with high accuracy (<0.1 cm -1 ). The change in normal coordinate influences the reduced mass of the oscillator and thus its frequency. Our results lead to a conclusion that the effect of deuterization of the methyl group introduces a very specific and consistent frequency shift of the first overtone of the O-X stretching mode depending on the substitution of X1, X2, or X3 positions (<2 cm -1 ). However, the pattern of this shift is not reproduced accurately and is also largely overestimated by VPT2

  16. Investigation of kinematic demixing of polymer blend deuterated polystyrene (d-PS) and polyvinylmethylether (PVME) with neutron small angle scattering

    International Nuclear Information System (INIS)

    Yee Madeira, H.T.

    1989-03-01

    The scope of this work is the investigation of the system PV ME/d-PS by small angle neutron scattering (SANS). The measurements were done with a pinhole-camera and a high resolution double crystal diffractometer and covered the resolution range from 10 -3 to 3x10 -2 A -1 and 2x10 -5 to 6x10 -4 A -1 respectively. As a basis for these investigations the phase diagram of a PVME/d-PS mixture was measured with SANS. The spinodal for different curve between stable and demixing region was obtained. For PVME with molecular weights M ω =60000 and d-PS with M ω =215103 the critical point is at the concentration Φ=0.2. From the spinodal and the structure factor the Flory-Huggins parameter Χ could be extracted as a function of temperature. It was found that Χ=0 for T comp =135 0 C and Χ is independent of the molecular weight within the accuracy of the data, thus Χ may be associated with a local interaction parameter. The scattering experiments for the determination of the spinodal confirmed the mean-field behaviour of the critical scattering which was earlier found by Herkt-Maetzky and Schelten. Further, the time dependence of the structure factor in the miscibility gap was investigated. From the structure factors, specially from the position Q max of their maxima, a characteristic length was extracted. (orig./RB) [de

  17. Quantitative determination of sulfur containing wine odorants at sub-ppb levels. 1. Synthesis of the deuterated analogues.

    Science.gov (United States)

    Kotseridis, Y; Ray, J L; Augier, C; Baumes, R

    2000-12-01

    [2H10]-4-Sulfanyl-4-methylpentan-2-one (d10-SMP), [2H2]-3-sulfanylhexan-1-ol (d2-3SH), and [2H5]-3-sulfanylhexyl acetate (d5-3SHAc), the labeled analogues of impact odorants of wines and other foods, were synthesized to be used for the quantitative determination of the natural compounds in white and red wines by stable isotope dilution assay. The sulfidation was achieved by Michael addition, on mesityl oxide or ethyl hex-2-enoate, respectively, of the sulfhydryl anion generated in situ from triphenylsilanethiol and potassium fluoride under phase transfer conditions. The labeling of 4-sulfanyl-4-methylpentan-2-one (SMP) was obtained from the commercial starting material, [2H6]acetone, so that this method could be used to synthesize 13C-labeled SMP from 13C-labeled acetone. The labeling of 3-sulfanylhexan-1-ol (3SH) and 3-sulfanylhexyl acetate (3SHAc) was obtained from reduction with lithium aluminum deuteride of the Michael adduct ethyl 3-sulfanylhexanoate and [2H3]-acetylation. During the synthesis, 3SH and 3SHAc were partially oxidized to their disulfide, which were reduced back to the thiols by an additional reduction step; the tertiary thiol SMP was less sensitive to this oxidation.

  18. Stereoselective semi-hydrogenation and deuteration of a diacetylenic precursor of leukotriene B sub 4 methyl ester

    Energy Technology Data Exchange (ETDEWEB)

    Pontikis, R.; Le Merrer, Y.; Depezay, J.-C. (U.D.C. CNRS-INSERM (URA 400), 75, Paris (France). Lab. de Chimie et Biochimie Pharamacologiques et Toxicologiques); Petillot, Y.; Rousseau, B.; Beaucourt, J.P. (CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France). Service des Molecules Marquees)

    1990-10-01

    (6,7,14,15-{sup 2}H4)-Leukotriene B4 methyl ester was prepared by reduction with deuterium gas of a suitable precursor (deuterium incorporation > 90%). Several catalytic semi-hydrogenations were affected in order to determine the best conditions for the labeling step. (author).

  19. Solvent deuteration enhancement of hydrophobicity: DSC study of the inverse temperature transition of elastin-based polypeptides

    International Nuclear Information System (INIS)

    Chihao Luan; Urry, D.W.

    1991-01-01

    As previously shown, the polypentapeptide of elastin, (Val 1 -Pro 2 -Gly 3 -Val 4 -Gly 5 ) n or simply poly(VPGVG), undergoes an inverse temperature transition which is seen macroscopically as a phase separation with a dense viscoelastic phase of about 60% water, 40% peptide by weight and which is characterized molecularly by increase in intra- and intermolecular order as evidenced by formation of specific hydrophobic contacts. Furthermore, from an extensive study of polypentapeptides of the composition poly[f x (VPGXG), f v (VPGVG)], where f x + f v = 1 and X is any of the amino acid residues with apolar (hydrophobic) side chains, it has been shown that the temperature of the transition decreases and the heat of the transition increases with increased hydrophobicity. In the present paper differential scanning calorimetry has been utilized to determine the effect of D 2 O on the temperature and heats of the inverse temperature transitions for poly(VPGVG), poly(IPGVG), poly(LPGVG), and poly(VPAVG) and in the latter case in the presence of 0.5 and 1.0 N NaCl and of 1,2, and 3 M urea. In all cases, the effect of D 2 O as compared to H 2 O is to lower the transition temperature about 2 C and to increase the heat of the transition about 10%, and this occurs also in the presence of NaCl, which itself lowers the temperature and increases the heat, and in the presence of urea, which itself raises the temperature and decreases the heat of the transition. It is concluded that the effect of replacement of H 2 O by D 2 O by D 2 O in these polypeptides is to effect a small but consistent increase in the expression of hydrophobicity

  20. An SFG study of interfacial amino acids at the hydrophilic SiO2 and hydrophobic deuterated polystyrene surfaces.

    Science.gov (United States)

    Holinga, George J; York, Roger L; Onorato, Robert M; Thompson, Christopher M; Webb, Nic E; Yoon, Alfred P; Somorjai, Gabor A

    2011-04-27

    Sum frequency generation (SFG) vibrational spectroscopy was employed to characterize the interfacial structure of eight individual amino acids--L-phenylalanine, L-leucine, glycine, L-lysine, L-arginine, L-cysteine, L-alanine, and L-proline--in aqueous solution adsorbed at model hydrophilic and hydrophobic surfaces. Specifically, SFG vibrational spectra were obtained for the amino acids at the solid-liquid interface between both hydrophobic d(8)-polystyrene (d(8)-PS) and SiO(2) model surfaces and phosphate buffered saline (PBS) at pH 7.4. At the hydrophobic d(8)-PS surface, seven of the amino acids solutions investigated showed clear and identifiable C-H vibrational modes, with the exception being l-alanine. In the SFG spectra obtained at the hydrophilic SiO(2) surface, no C-H vibrational modes were observed from any of the amino acids studied. However, it was confirmed by quartz crystal microbalance that amino acids do adsorb to the SiO(2) interface, and the amino acid solutions were found to have a detectable and widely varying influence on the magnitude of SFG signal from water at the SiO(2)/PBS interface. This study provides the first known SFG spectra of several individual amino acids in aqueous solution at the solid-liquid interface and under physiological conditions.

  1. Alternative interpretation of low-energy nuclear reaction processes with deuterated metals based on the Bose-Einstein condensation mechanism

    International Nuclear Information System (INIS)

    Yeong, E. Kim; Passell, Thomas O.

    2006-01-01

    Recently, a generalization of the Bose-Einstein condensation (BEC) mechanism has been made to a ground-state mixture of two different species of positively charged bosons in harmonic traps. The theory has been used to describe (D + Li) reactions in the low energy nuclear reaction (LENR) processes in condensed matter and predicts that the (D + Li) reaction rates can be larger than (D + D) reaction rates by as much as a factor of ∼ 50, implying that (D + Li) reactions may be occurring in addition to the (D + D) reactions. A survey of the existing data from LENR experiments is carried out to check the validity of the theoretical prediction. We conclude that there is compelling experimental evidence which support the theoretical prediction. New experimental tests of the theoretical prediction are suggested. (authors)

  2. Alternative Interpretation of Low-Energy Nuclear Reaction Processes with Deuterated Metals Based on the Bose-Einstein Condensation Mechanism

    Science.gov (United States)

    Kim, Yeong E.; Passell, Thomas O.

    2006-02-01

    Recently, a generalization of the Bose-Einstein condensation (BEC) mechanism has been made to a ground-state mixture of two different species of positively charged bosons in harmonic traps. The theory has been used to describe (D + Li) reactions in the low energy nuclear reaction (LENR) processes in condensed matter and predicts that the (D + Li) reaction rates can be larger than (D + D) reaction rates by as much as a factor of ~50, implying that (D + Li) reactions may be occuring in addition to the (D + D) reactions. A survey of the existing data from LENR experiments is carried out to check the validity of the theoretical prediction. We conclude that there is compelling experimental evidence which support the theoretical prediction. New experimental tests of the theoretical prediction are suggested.

  3. Alternative interpretation of low-energy nuclear reaction processes with deuterated metals based on the Bose-Einstein condensation mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Yeong, E. Kim [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Passell, Thomas O. [TOP Consulting, PO Box 336, Palo Alto, CA 94302-0336 (United States)

    2006-07-01

    Recently, a generalization of the Bose-Einstein condensation (BEC) mechanism has been made to a ground-state mixture of two different species of positively charged bosons in harmonic traps. The theory has been used to describe (D + Li) reactions in the low energy nuclear reaction (LENR) processes in condensed matter and predicts that the (D + Li) reaction rates can be larger than (D + D) reaction rates by as much as a factor of {approx} 50, implying that (D + Li) reactions may be occurring in addition to the (D + D) reactions. A survey of the existing data from LENR experiments is carried out to check the validity of the theoretical prediction. We conclude that there is compelling experimental evidence which support the theoretical prediction. New experimental tests of the theoretical prediction are suggested. (authors)

  4. Breath analysis of ammonia, volatile organic compounds and deuterated water vapor in chronic kidney disease and during dialysis

    Czech Academy of Sciences Publication Activity Database

    Davies, S. J.; Španěl, Patrik; Smith, D.

    2014-01-01

    Roč. 6, č. 6 (2014), s. 843-857 ISSN 1757-6180 Institutional support: RVO:61388955 Keywords : ion-flow tube * reaction-mass-spectrometry * trace gas analysis Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.003, year: 2014

  5. Body composition using deuterated water, index of insulin resistance and cortisol levels in Costa Rican school in the metropolitan area

    International Nuclear Information System (INIS)

    Valverde Vindas, Allan Ignacio

    2014-01-01

    Body composition in the Costa Rican child population is evaluated and analyzed to determine the relationship with the index of insulin resistance and serum cortisol levels. 113 children in the metropolitan area were studied using deuterium isotope techniques as reference method for overweight and obesity. Morning cortisol levels were determined by immunoassay techniques (ELISA). The insulin resistance index of 113 Costa Rican boys and girls is obtained by the homeostatic method and the relationship between body composition with index of insulin resistance or levels of cortisol [es

  6. Quantification of the selective activation of C--H bonds in short chain alkanes: The reactivity of ethane, propane, isobutane, n-butane, and neopentane on Ir(111)

    International Nuclear Information System (INIS)

    Johnson, D.F.; Weinberg, W.H.

    1995-01-01

    The initial probabilities of precursor-mediated, dissociative chemisorption of the saturated hydrocarbons 13 C-labeled ethane, propane, isobutane, n-butane, and neopentane on the close-packed Ir(111) surface have been measured. The selective activation of primary (1 degree), secondary (2 degree), and tertiary (3 degree) C--H bonds has been quantified by examining the reactivities of the selectively deuterated isotopomers of propane, C 3 H 8 , CH 3 CD 2 CH 3 , and C 3 D 8 , and of isobutane, (CH 3 ) 3 CH, (CH 3 ) 3 CD, and (CD 3 ) 3 CH. With respect to the bottom of the physically adsorbed well for each hydrocarbon, the apparent C--H bond activation energies have been found to be 10.4±0.3 kcal/mol (ethane), 11.4±0.3 kcal/mol (propane), 11.5±0.3 kcal/mol (n-butane), 11.3±0.3 kcal/mol (i-butane), and 11.3±0.3 kcal/mol (neopentane). For all the alkanes examined, the ratios of the preexponential factors of the rate coefficients of reaction and desorption are 1x10 -2 . The C--D bond activation energies are higher than the corresponding C--H bond activation energies by 480 cal/mol (ethane), 630 cal/mol (propane), and 660 cal/mol (i-butane). By analyzing the primary kinetic isotope effects for the selectively deuterated isotopomers of propane and isobutane, the 2 degree C--H bond activation energy is found to be 310±160 cal/mol less than the 1 degree C--H bond activation energy on this surface, and similarly, 3 degree C--H bond cleavage is less by 80±70 cal/mol. The quantification of the branching ratios within the C--H bond activation channel for propane and isobutane on this surface shows that the formation of 1 degree-alkyl intermediates is, in general, favored over the formation of either 2 degree- or 3 degree-alkyl intermediates. (Abstract Truncated)

  7. Sulphur chemistry in the L1544 pre-stellar core

    Science.gov (United States)

    Vastel, Charlotte; Quénard, D.; Le Gal, R.; Wakelam, V.; Andrianasolo, A.; Caselli, P.; Vidal, T.; Ceccarelli, C.; Lefloch, B.; Bachiller, R.

    2018-05-01

    The L1544 pre-stellar core has been observed as part of the ASAI IRAM 30m Large Program as well as follow-up programs. These observations have revealed the chemical richness of the earliest phases of low-mass star-forming regions. In this paper we focus on the twenty-one sulphur bearing species (ions, isotopomers and deuteration) that have been detected in this spectral-survey through fifty one transitions: CS, CCS, C3S, SO, SO2, H2CS, OCS, HSCN, NS, HCS+, NS+ and H2S. We also report the tentative detection (4 σ level) for methyl mercaptan (CH3SH). LTE and non-LTE radiative transfer modelling have been performed and we used the NAUTILUS chemical code updated with the most recent chemical network for sulphur to explain our observations. From the chemical modelling we expect a strong radial variation for the abundances of these species, which mostly are emitted in the external layer where non thermal desorption of other species has previously been observed. We show that the chemical study cannot be compared to what has been done for the TMC-1 dark cloud, where the abundance is supposed constant along the line of sight, and conclude that a strong sulphur depletion is necessary to fully reproduce our observations of the prototypical pre-stellar core L1544.

  8. Anharmonic vibrational spectroscopic investigation of malonaldehyde

    International Nuclear Information System (INIS)

    Alparone, A.; Millefiori, S.

    2003-01-01

    Anharmonic IR spectra of H-bonded and non-H-bonded conformers of malonaldehyde (MA) and its isotopomers MA-D 6 D 8 and MA-D 7 D 9 have been computed by the Vibrational-Self-Consistent-Field (VSCF) and the correlation-corrected-VSCF (CC-VSCF) techniques using ab initio MP2/6-31G*(+p) potential energies. The agreement between the experimental and calculated frequencies is significantly improved to within 2-3%. Anharmonic contributions are substantial especially for νOH of the H-bonded form, by reducing the harmonic value by more than 500 cm -1 . The effect is less important in the non-H-bonded form. The νOH stretching mode is strongly coupled with the ν 3 mode (essentially νCH 7 ) and with the in-plane and out-of-plane OH bending deformations. H-bond formation and deuteration batochromically shift νOH by an amount which is influenced by the anharmonic terms, the major contribution arising from coupling between modes. The comparison with the νOH mode of some other H-bonded systems suggests that anharmonic correction follows H-bonding strength

  9. Quantum-mechanical study of energies, structures, and vibrational spectra of the H(D)Cl complexed with dimethyl ether

    Energy Technology Data Exchange (ETDEWEB)

    Boda, Łukasz, E-mail: lboda@chemia.uj.edu.pl; Boczar, Marek; Gług, Maciej; Wójcik, Marek J. [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Kraków (Poland)

    2015-11-28

    Interaction energies, molecular structure and vibrational frequencies of the binary complex formed between H(D)Cl and dimethyl ether have been obtained using quantum-chemical methods. Equilibrium and vibrationally averaged structures, harmonic and anharmonic wavenumbers of the complex and its deuterated isotopomer were calculated using harmonic and anharmonic second-order perturbation theory procedures with Density Functional Theory B3LYP and B2PLYP-D and ab initio Møller-Plesset second-order methods, and a 6-311++G(3d,3p) basis set. A phenomenological model describing anharmonic-type vibrational couplings within hydrogen bonds was developed to explain the unique broadening and fine structure, as well as the isotope effect of the Cl–H and Cl–D stretching IR absorption bands in the gaseous complexes with dimethyl ether, as an effect of hydrogen bond formation. Simulations of the rovibrational structure of the Cl–H and Cl–D stretching bands were performed and the results were compared with experimental spectra.

  10. Trajectory Calculations for Bergman Cyclization Predict H/D Kinetic Isotope Effects Due to Nonstatistical Dynamics in the Product.

    Science.gov (United States)

    Doubleday, Charles; Boguslav, Mayla; Howell, Caronae; Korotkin, Scott D; Shaked, David

    2016-06-22

    An unusual H/D kinetic isotope effect (KIE) is described, in which isotopic selectivity arises primarily from nonstatistical dynamics in the product. In DFT-based quasiclassical trajectories of Bergman cyclization of (Z)-3-hexen-1,5-diyne (1) at 470 K, the new CC bond retains its energy, and 28% of nascent p-benzyne recrosses back to the enediyne on a vibrational time scale. The competing process of intramolecular vibrational redistribution (IVR) in p-benzyne is too slow to prevent this. Deuteration increases the rate of IVR, which decreases the fraction of recrossing and increases the yield of statistical (trapable) p-benzyne, 2. Trapable yields for three isotopomers of 2 range from 72% to 86%. The resulting KIEs for Bergman cyclization differ substantially from KIEs predicted by transition state theory, which suggests that IVR in this reaction can be studied by conventional KIEs. Leakage of vibrational zero point energy (ZPE) into the reaction coordinate was probed by trajectories in which initial ZPE in the CH/CD stretching modes was reduced by 25%. This did not change the predicted KIEs.

  11. Excited State Structural Dynamics of Carotenoids and Charge Transfer Systems

    International Nuclear Information System (INIS)

    Van Tassle, Aaron Justin

    2006-01-01

    This dissertation describes the development and implementation of a visible/near infrared pump/mid-infrared probe apparatus. Chapter 1 describes the background and motivation of investigating optically induced structural dynamics, paying specific attention to solvation and the excitation selection rules of highly symmetric molecules such as carotenoids. Chapter 2 describes the development and construction of the experimental apparatus used throughout the remainder of this dissertation. Chapter 3 will discuss the investigation of DCM, a laser dye with a fluorescence signal resulting from a charge transfer state. By studying the dynamics of DCM and of its methyl deuterated isotopomer (an otherwise identical molecule), we are able to investigate the origins of the charge transfer state and provide evidence that it is of the controversial twisted intramolecular (TICT) type. Chapter 4 introduces the use of two-photon excitation to the S1 state, combined with one-photon excitation to the S2 state of the carotenoid beta-apo-8'-carotenal. These 2 investigations show evidence for the formation of solitons, previously unobserved in molecular systems and found only in conducting polymers Chapter 5 presents an investigation of the excited state dynamics of peridinin, the carotenoid responsible for the light harvesting of dinoflagellates. This investigation allows for a more detailed understanding of the importance of structural dynamics of carotenoids in light harvesting

  12. Excited State Structural Dynamics of Carotenoids and ChargeTransfer Systems

    Energy Technology Data Exchange (ETDEWEB)

    Van Tassle, Aaron Justin [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    This dissertation describes the development andimplementation of a visible/near infrared pump/mid-infrared probeapparatus. Chapter 1 describes the background and motivation ofinvestigating optically induced structural dynamics, paying specificattention to solvation and the excitation selection rules of highlysymmetric molecules such as carotenoids. Chapter 2 describes thedevelopment and construction of the experimental apparatus usedthroughout the remainder of this dissertation. Chapter 3 will discuss theinvestigation of DCM, a laser dye with a fluorescence signal resultingfrom a charge transfer state. By studying the dynamics of DCM and of itsmethyl deuterated isotopomer (an otherwise identical molecule), we areable to investigate the origins of the charge transfer state and provideevidence that it is of the controversial twisted intramolecular (TICT)type. Chapter 4 introduces the use of two-photon excitation to the S1state, combined with one-photon excitation to the S2 state of thecarotenoid beta-apo-8'-carotenal. These 2 investigations show evidencefor the formation of solitons, previously unobserved in molecular systemsand found only in conducting polymers Chapter 5 presents an investigationof the excited state dynamics of peridinin, the carotenoid responsiblefor the light harvesting of dinoflagellates. This investigation allowsfor a more detailed understanding of the importance of structuraldynamics of carotenoids in light harvesting.

  13. Diffusion Monte Carlo studies of MB-pol (H{sub 2}O){sub 2−6} and (D{sub 2}O){sub 2−6} clusters: Structures and binding energies

    Energy Technology Data Exchange (ETDEWEB)

    Mallory, Joel D.; Mandelshtam, Vladimir A. [Department of Chemistry, University of California, Irvine, California 92697 (United States)

    2016-08-14

    We employ the diffusion Monte Carlo (DMC) method in conjunction with the recently developed, ab initio-based MB-pol potential energy surface to characterize the ground states of small (H{sub 2}O){sub 2−6} clusters and their deuterated isotopomers. Observables, other than the ground state energies, are computed using the descendant weighting approach. Among those are various spatial correlation functions and relative isomer fractions. Interestingly, the ground states of all clusters considered in this study, except for the dimer, are delocalized over at least two conformations that differ by the orientation of one or more water monomers with the relative isomer populations being sensitive to the isotope substitution. Most remarkably, the ground state of the (H{sub 2}O){sub 6} hexamer is represented by four distinct cage structures, while that of (D{sub 2}O){sub 6} is dominated by the prism, i.e., the global minimum geometry, with a very small contribution from a prism-book geometry. In addition, for (H{sub 2}O){sub 6} and (D{sub 2}O){sub 6}, we performed DMC calculations to compute the ground states constrained to the cage and prism geometries. These calculations compared results for three different potentials, MB-pol, TTM3/F, and q-TIP4P/F.

  14. A quantum generalization of intrinsic reaction coordinate using path integral centroid coordinates

    International Nuclear Information System (INIS)

    Shiga, Motoyuki; Fujisaki, Hiroshi

    2012-01-01

    We propose a generalization of the intrinsic reaction coordinate (IRC) for quantum many-body systems described in terms of the mass-weighted ring polymer centroids in the imaginary-time path integral theory. This novel kind of reaction coordinate, which may be called the ''centroid IRC,'' corresponds to the minimum free energy path connecting reactant and product states with a least amount of reversible work applied to the center of masses of the quantum nuclei, i.e., the centroids. We provide a numerical procedure to obtain the centroid IRC based on first principles by combining ab initio path integral simulation with the string method. This approach is applied to NH 3 molecule and N 2 H 5 - ion as well as their deuterated isotopomers to study the importance of nuclear quantum effects in the intramolecular and intermolecular proton transfer reactions. We find that, in the intramolecular proton transfer (inversion) of NH 3 , the free energy barrier for the centroid variables decreases with an amount of about 20% compared to the classical one at the room temperature. In the intermolecular proton transfer of N 2 H 5 - , the centroid IRC is largely deviated from the ''classical'' IRC, and the free energy barrier is reduced by the quantum effects even more drastically.

  15. Sub-Doppler and Doppler Spectroscopy of DCN Isotopomers in the Terahertz Region: Ground and First Excited Bending States (.nu.1 .nu.2 .nu.3) =0 1ef O)

    Czech Academy of Sciences Publication Activity Database

    Brünken, S.; Fuchs, U.; Lewen, F.; Urban, Štěpán; Giesen, T.; Winnewisser, G.

    2004-01-01

    Roč. 225, č. 2 (2004), s. 152-161 ISSN 0022-2852 R&D Projects: GA ČR GA203/01/1274; GA MŠk ME 445 Institutional research plan: CEZ:AV0Z4040901 Keywords : molecular spectroscopy * sub-Doppler spectroscopy * high-resolution spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.292, year: 2004

  16. Association equilibrium constants and populations of clusters (H2O)n(g) and (D2O)n(g): differences between isotopomers and a possible relation to isotope enrichment

    International Nuclear Information System (INIS)

    Slanina, Z.

    1986-01-01

    Equilibrium constants of H 2 O(g) and D 2 O(g) associations to clusters (H 2 O) n (g) and (D 2 O) n (g) were calculated on the basis of the ab initio SCF CI MCY-B water-water pair potential. Populations of the components of equilibrium cluster mixtures were evaluated at various temperatures and pressures for both isotopomeric series. Differences between the H and D steam are pointed out and possible consequences are discussed. (author)

  17. Sodalite Cancrinite Nepheline Syenite of Mendanha Massif, State of Rio de Janeiro, Brazil, Called Commercially Blue Guanabara Granite, and its Origin from Deuteric Metasomatism

    Directory of Open Access Journals (Sweden)

    Akihisa Motoki

    2015-01-01

    Full Text Available Este artigo apresenta observações de campo, descrições petrográficas e considerações genéticas do sodalita cancrinita nefelina sienito, chamado comercialmente de Granito Cinza Azul Guanabara, que se encontra na zona de contato sudoeste da intrusão alcalina félsica de Mendanha, RJ. Esta rocha ornamental ocorre ao longo do eixo central de um dique sienítico com 15 m de largura. A cor macroscópica em rocha total é caracterizada por saturação baixa (S=5~7 e clareza média (B~62. A cor de minerais opacos tem clareza relativamente alta (B~28. O feldspato alcalino é comumente alterado em muscovita. Os feldspatóides são presentes nos espaços intersticiais do arcabouço de feldspato alcalino. O anfibólio e biotita são alterados em minerais opacos e vermiculita, apresentando pseudomorfo. Os minerais acessórios são magnetita primária e titanita. Existe uma significativa quantidade de carbonatos com quantidade modal de 6,8%, constituindo agregados de forma irregular ou preenchendo espaços. A cor macroscópica dos agregados de feldspatóides varia de azul profundo para azul claro de acordo com o teor relativo de sodalita. A sodalita e cancrinita são originadas de nefelina e foram formadas através de metassomatismo deutérico do fluído rico em Cl

  18. Facile synthesis of deuterated and [14C]labeled analogues of vanillin and curcumin for use as mechanistic and analytical tools

    Science.gov (United States)

    Gordon, Odaine N.; Graham, Leigh A.; Schneider, Claus

    2014-01-01

    Curcumin is a dietary diphenol with antioxidant, antinflammatory and antitumor activity. We describe facile procedures for the synthesis of [14C2]curcumin (4 mCi/mmol), [d6]curcumin, [d3]curcumin, [13C5]curcumin, and [d6]bicyclopentadione, the major oxidative metabolite of curcumin. We also describe synthesis of the labeled building blocks [14C]vanillin, [d3]vanillin, and [13C5]acetylacetone. The overall molar yields of the labeled products were 52% ([14C]) and 47% ([d3]) for vanillin and 25% ([14C2]) and 27% ([d6]) for curcumin. The compounds can be used as radiotracers in biotransformation studies and as isotopic standards for mass spectrometry-based quantification in pharmacokinetic analyses. PMID:24339007

  19. Low temperature heat capacity measurements of the spin-liquid states of hydrogenated and deuterated κ-(BEDT-TTF)2Cu2(CN)3

    International Nuclear Information System (INIS)

    Yamashita, S.; Yamamoto, T.; Nakazawa, Y.

    2010-01-01

    Heat capacity measurements of organic triangular lattice compound κ-(BEDT-TTF) 2 Cu 2 (CN) 3 were performed to discuss the low energy excitations from the spin-liquid ground states. Existence of the T-linear electronic coefficient with finite electronic heat capacity coefficient γ was confirmed in three different samples from different batches, although small sample dependence was observed in the absolute values of the heat capacities. Concerning the sample in which hydrogen atoms in ethylene group in BEDT-TTF molecule have been substituted by deuterons, we have observed almost similar thermodynamic behavior as the hydrogenated sample. The absence of drastic change of electronic properties of this compound is consistent with the electronic phase diagram given by Kurosaki et al. [11] (Phys. Rev. Lett. 95 (2005) 17001). The obtained data are well consistent with the previous heat capacity experiments. The existence of the γ term demonstrates that the excitations from the quantum spin-liquid states show a gapless behavior at least down to 0.7 K.

  20. Investigation of a CER[NP]- and [AP]-Based Stratum Corneum Modeling Membrane System: Using Specifically Deuterated CER Together with a Neutron Diffraction Approach.

    Science.gov (United States)

    Schmitt, Thomas; Lange, Stefan; Dobner, Bodo; Sonnenberger, Stefan; Hauß, Thomas; Neubert, Reinhard H H

    2018-01-30

    Neutron diffraction was used as a tool to investigate the lamellar as well as molecular nanostructure of ceramide-[NP]/ceramide-[AP]/cholesterol/lignoceric acid model systems with a nativelike 2:1 ratio and a 1:2 ratio to study the influence of the ceramide-[AP]. By using mixtures together with cholesterol and free fatty acids as well as a humidity and temperature chamber while measuring, natural conditions were simulated as closely as possible. Despite its simplicity, the system simulated the native stratum corneum lipid matrix fairly closely, showing a similar lamellar thickness with a repeat distance of 5.45 ± 0.1 nm and a similar arrangement with overlapping long C24 chains. Furthermore, despite the very minor chemical difference between ceramide-[NP] and ceramide-[AP], which is only a single OH group, it was possible to demonstrate substantial differences between the structural influence of the two ceramides. Ceramide-[AP] could be concluded to be arranged in such a way that its C24 chain in both ratios is somehow shorter than that of ceramide-[NP], not overlapping as much with the opposite lamellar leaflet. Furthermore, in the unnatural 1:2 ratio, the higher ceramide-[AP] content causes an increased tilt of the ceramide acyl chains. This leads to even less overlapping within the lamellar midplane, whereas the repeat distance stays the same as for the ceramide-[NP]-rich system. In this nativelike 2:1 ratio, the chains are arranged mostly straight, and the long C24 chains show a broad overlapping region in the lamellar midplane.

  1. Injection of deuterated water into the pulmonary/alveolar circulation; measurement of HDO in exhaled breath and implications to breath analysis

    Czech Academy of Sciences Publication Activity Database

    Tan, B. K.; Davies, S. J.; Španěl, Patrik; Smith, D.

    2012-01-01

    Roč. 6, č. 3 (2012), 036005 ISSN 1752-7155 Institutional support: RVO:61388955 Keywords : total body water * afterglow mass spectrometry * deuterium abundance Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.571, year: 2012

  2. [Peculiarities of growth of the monocellular green algae culture after the influence of electromagnetic field in deuterated water-containing media].

    Science.gov (United States)

    Semenov, K T; Aslanian, R R

    2013-01-01

    Exposing the inoculum of monocellular green algae Dunalialla tertiolecta and Tetraselmis viridis to 50 Hz electromagnetic field for several hours resulted in a reduced growth rate in both cultures. It was ascertained that heavy water inhibited growth of algae Dunaliella tertiolecta. The light water activated growth of the culture in the exponential phase only.

  3. Metabolite kinetics: formation of acetaminophen from deuterated and nondeuterated phenacetin and acetanilide on acetaminophen sulfation kinetics in the perfused rat liver preparation

    International Nuclear Information System (INIS)

    Pang, K.S.; Waller, L.; Horning, M.G.; Chan, K.K.

    1982-01-01

    The role of hepatic intrinsic clearance for metabolite formation from various precursors on subsequent metabolite elimination was was investigated in the once-through perfused rat liver preparation. Two pairs of acetaminophen precursors: [ 14 C] phenacetin-d5 and [ 3 H] phenacetin-do, [ 14 C] acetanilide and [ 3 H] phenacetin were delivered by constant flow (10 ml/min/liver) either by normal or retrograde perfusion to the rat liver preparations. The extents of acetaminophen sulfation were compared within the same preparation. The data showed that the higher the hepatocellular activity (intrinsic clearance) for acetaminophen formation, the greater the extent of subsequent acetaminophen sulfation. The findings were explained on the basis of blood transit time and metabolite duration time. Because of blood having only a finite transit time in liver, the longer the drug requires for metabolite formation, the less time will remain for metabolite sulfation and the less will be the degree of subsequent sulfation. Conversely, when the drug forms the primary metabolite rapidly, a longer time will remain for the metabolite to be sulfated in liver to result in a greater degree of metabolite sulfation. Finally, the effects of hepatic intrinsic clearances for metabolite formation and zonal distribution of enzyme systems for metabolite formation and elimination in liver are discussed

  4. Unifying theory of low-energy nuclear reaction and transmutation processes in deuterated/hydrogenated metals, acoustic cavitation, glow discharge, and deuteron beam experiments

    International Nuclear Information System (INIS)

    Kim, Yeong E.; Zubarev, Alexander L.

    2006-01-01

    The most basic theoretical challenge for understanding low-energy nuclear reaction (LENR) and transmutation reaction (LETR) in condensed matters is to find mechanisms by which the large Coulomb barrier between fusing nuclei can be overcome. A unifying theory of LENR and LETR has been developed to provide possible mechanisms for the LENR and LETR processes in matters based on high-density nano-scale and micro-scale quantum plasmas. It is shown that recently developed theoretical models based on Bose-Einstein Fusion (BEF) mechanism and Quantum Plasma Nuclear Fusion (QPNF) mechanism are applicable to the results of many different types of LENR and LETR experiments. (author)

  5. Unifying Theory of Low-Energy Nuclear Reaction and Transmutation Processes in Deuterated/hydrogenated Metals, Acoustic Cavitation, Glow Discharge, and Deuteron Beam Experiments

    Science.gov (United States)

    Kim, Yeong E.; Zubarev, Alexander L.

    The most basic theoretical challenge for understanding low-energy nuclear reaction (LENR) and transmutation reaction (LETR) in condensed matters is to find mechanisms by which the large Coulomb barrier between fusing nuclei can be overcome. A unifying theory of LENR and LETR has been developed to provide possible mechanisms for the LENR and LETR processes in matters based on high-density nano-scale and micro-scale quantum plasmas. It is shown that recently developed theoretical models based on Bose-Einstein Fusion (BEF) mechanism and Quantum Plasma Nuclear Fusion (QPNF) mechanism are applicable to the results of many different types of LENR and LETR experiments.

  6. Dispersal kinetics of deuterated water in the lungs and airways following mouth inhalation: real-time breath analysis by flowing afterglow mass spectrometry (FA-MS)

    Czech Academy of Sciences Publication Activity Database

    Tan, B. K.; Smith, D.; Španěl, Patrik; Davies, S. J.

    2010-01-01

    Roč. 4, č. 1 (2010), 017109 ISSN 1752-7155 Institutional research plan: CEZ:AV0Z40400503 Keywords : mass spectrometry * breath analysis * pulmonary-edema Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.828, year: 2010

  7. Detection of the sulfhydryl groups in proteins with slow hydrogen exchange rates and determination of their proton/deuteron fractionation factors using the deuterium-induced effects on the 13C(beta) NMR signals.

    Science.gov (United States)

    Takeda, Mitsuhiro; Jee, JunGoo; Terauchi, Tsutomu; Kainosho, Masatsune

    2010-05-05

    A method for identifying cysteine (Cys) residues with sulfhydryl (SH) groups exhibiting slow hydrogen exchange rates has been developed for proteins in aqueous media. The method utilizes the isotope shifts of the C(beta) chemical shifts induced by the deuteration of the SH groups. The 18.2 kDa E. coli peptidyl prolyl cis-trans isomerase b (EPPIb), which was selectively labeled with [3-(13)C;3,3-(2)H(2)]Cys, showed much narrower line widths for the (13)C(beta) NMR signals, as compared to those of the proteins labeled with either [3-(13)C]Cys or (3R)-[3-(13)C;3-(2)H]Cys. The (13)C(beta) signals of the two Cys residues of EPPIb, i.e. Cys-31 and Cys-121, labeled with [3-(13)C;3,3-(2)H(2)]Cys, split into four signals in H(2)O/D(2)O (1:1) at 40 degrees C and pH 7.5, indicating that the exchange rates of the side-chain SH's and the backbone amides are too slow to average the chemical shift differences of the (13)C(beta) signals, due to the two- and three-bond isotope shifts. By virtue of the well-separated signals, the proton/deuteron fractional factors for both the SH and amide groups of the two Cys residues in EPPIb could be directly determined, as approximately 0.4-0.5 for [SD]/[SH] and 0.9-1.0 for [ND]/[NH], by the relative intensities of the NMR signals for the isotopomers. The proton NOE's of the two slowly exchanging SH's were clearly identified in the NOESY spectra and were useful for the determining the local structure of EPPIb around the Cys residues.

  8. Comparison of the local binding motifs in the imidazolium-based ionic liquids [EMIM][BF{sub 4}] and [EMMIM][BF{sub 4}] through cryogenic ion vibrational predissociation spectroscopy: Unraveling the roles of anharmonicity and intermolecular interactions

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, Joseph A.; Wolke, Conrad T.; Johnson, Christopher J.; Johnson, Mark A., E-mail: mark.johnson@yale.edu, E-mail: mccoy@chemistry.ohio-state.edu [Sterling Chemistry Laboratory, Yale University, New Haven, Connecticut 06520 (United States); McCoy, Anne B., E-mail: mark.johnson@yale.edu, E-mail: mccoy@chemistry.ohio-state.edu [Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210 (United States)

    2015-02-14

    We clarify the role of the critical imidazolium C{sub (2)}H position (the central C between N atoms in the heterocycle) in the assembly motif of the [EMIM][BF{sub 4}] ionic liquid by analyzing the vibrational spectra of the bare EMIM{sup +} ion as well as that of the cationic [EMIM]{sub 2}[BF{sub 4}]{sup +} (EMIM{sup +} = 1-ethyl-3-methylimidazolium, C{sub 6}H{sub 11}N{sub 2}{sup +}) cluster. Vibrational spectra of the cold, mass-selected ions are obtained using cryogenic ion vibrational predissociation of weakly bound D{sub 2} molecules formed in a 10 K ion trap. The C{sub (2)}H behavior is isolated by following the evolution of key vibrational features when the C{sub (2)} hydrogen, the proposed binding location of the anion to the imidazolium ring, is replaced by either deuterium or a methyl group (i.e., in the EMMIM{sup +} analogue). Strong features in the ring CH stretching region of the bare ion are traced to Fermi resonances with overtones of lower frequency modes. Upon incorporation into the EMIM{sup +} ⋅ ⋅ ⋅ BF{sub 4}{sup −} ⋅ ⋅ ⋅ EMIM{sup +} ternary complex, the C{sub (2)}H oscillator strength is dramatically increased, accounting for the much more complicated patterns derived from the EMIM{sup +} ring CH stretches in the light isotopomer, which are strongly suppressed in the deuterated analogue. Further changes in the spectra that occur when the C{sub (2)}H is replaced by a methyl group are consistent with BF{sub 4}{sup −} attachment directly to the imidazolium ring in an arrangement that maximizes the electrostatic interaction between the molecular ions.

  9. Synthesis of trans-4,5-epoxy-(E)-2-decenal and its deuterated analog used for the development of a sensitive and selective quantification method based on isotope dilution assay with negative chemical ionization.

    Science.gov (United States)

    Lin, J; Fay, L B; Welti, D H; Blank, I

    1999-10-01

    The volatile compound trans-4,5-epoxy-(E)-2-decenal (1) was synthesized in two steps with good overall yields. The newly developed method is based on trans-epoxidation of (E)-2-octenal with alkaline hydrogen peroxide followed by a Wittig-type chain elongation with the ylide formylmethylene triphenylphosphorane. For the synthesis of [4,5-2H2]-trans-4,5-epoxy-(E)-2-decenal (d-1), [2,3-2H2]-(E)-2-octenal was prepared by reduction of 2-octyn-1-ol with lithium aluminum deuteride and subsequent oxidation of [2,3-2H2]-(E)-2-octen-1-ol with manganese oxide. Compound d1 was used as internal standard for the quantification of 1 by isotope dilution assay. Among various mass spectrometry (MS) ionization techniques tested, negative chemical ionization with ammonia as reagent gas gave best results with respect to both sensitivity and selectivity. The detection limit was found to be at about 1 pg of the analyte introduced into the gas chromatography-MS system.

  10. RATE CONSTANTS FOR THE REACTIONS OF OH RADICALS AND CL ATOMS WITH DI-N-PROPYL ETHER AND DI-N-BUTYL ETHER AND THEIR DEUTERATED ANALOGS. (R825252)

    Science.gov (United States)

    Using relative rate methods, rate constants for the gas-phase reactions of OH radicals and Cl atoms with di-n-propyl ether, di-n-propyl ether-d14, di-n-butyl ether and di-n-butyl ether-d18 have been measured at 296 ? 2 K and atmos...

  11. Reinvestigating 2,5-di(pyridin-2-yl)pyrazine ruthenium complexes : Selective deuteration and Raman spectroscopy as tools to probe ground and excited-state electronic structure in homo- and heterobimetallic complexes

    NARCIS (Netherlands)

    Schulz, M.; Hirschmann, J.; Draksharapu, A.; Singh Bindra, G.; Soman, S.; Paul, A.; Groarke, R.; T. Pryce, M.; Rau, S.; R. Browne, W.; Vos, J.

    2011-01-01

    The mono- (1) and dinuclear (2) ruthenium(II) bis(2,2'-bipyridine) complexes of 2,5-di(pyridin-2-yl)pyrazine (2,5-dpp), for which the UV/Vis absorption and emission as well as electrochemical properties have been described earlier, are reinvestigated here by resonance, surface enhanced and transient

  12. Dehydroepiandrosterone sulfate quantification in serum using high-performance liquid chromatography/mass spectrometry and a deuterated internal standard: a technique suitable for routine use or as a reference method

    International Nuclear Information System (INIS)

    Shackleton, C.H.; Kletke, C.; Wudy, S.; Pratt, J.H.

    1990-01-01

    A thermospray high-performance liquid chromatography/mass spectrometry method for determination of serum dehydroepiandrosterone sulfate is described. The steroid was measured intact using [7,7-2H2]dehydroepiandrosterone sulfate as internal standard. The analysis was carried out in the negative ion mode by determining the peak height ratio of the molecular anions of the analyte and internal standard. The method was used to determine the steroid in serum from 15 male and female normal adults and the following values were obtained: males, 272 +/- 45 micrograms/dl (range, 197 to 331 micrograms/dl) and females, 215 +/- 67 micrograms/dl (range, 107 to 347 micrograms/dl). In addition, dehydroepiandrosterone sulfate was measured by high-performance liquid chromatography/mass spectrometry and radioimmunoassay (a commercial kit) on 25 individuals of all age groups. There was strong correlation between the values obtained, but the radioimmunoassay values were generally double those obtained by high-performance liquid chromatography/mass spectrometry. Three other steroid sulfates, androsterone sulfate, epiandrosterone sulfate, and androst-5-ene-3 beta, 17 beta-diol sulfate, were also assayed. In males, these had mean values of 112, 44, and 13 micrograms/dl and, in females, they had mean values of 84, 25, and 6 micrograms/dl, respectively. Radioimmunoassay cross-reactivity measurement for these steroids (as reference compounds) showed that they were unlikely to contribute greatly to the discrepancy between radioimmunoassay and high-performance liquid chromatography/mass spectrometry values

  13. The Crystal Structure of a High-Spin Oxoiron(IV) Complex and Characterization of Its Self-Decay Pathway

    Energy Technology Data Exchange (ETDEWEB)

    England, J.; Guo, Y; Farquhar, E; Young, Jr., V; Münck, E; Que, Jr., L

    2010-01-01

    [Fe{sup IV}(O)(TMG{sub 3}tren)]{sup 2+} (1; TMG{sub 3}tren = 1,1,1-tris{l_brace}2-[N{sup 2}-(1,1,3,3-tetramethylguanidino)]ethyl{r_brace}amine) is a unique example of an isolable synthetic S = 2 oxoiron(IV) complex, which serves as a model for the high-valent oxoiron(IV) intermediates observed in nonheme iron enzymes. Congruent with DFT calculations predicting a more reactive S = 2 oxoiron(IV) center, 1 has a lifetime significantly shorter than those of related S = 1 oxoiron(IV) complexes. The self-decay of 1 exhibits strictly first-order kinetic behavior and is unaffected by solvent deuteration, suggesting an intramolecular process. This hypothesis was supported by ESI-MS analysis of the iron products and a significant retardation of self-decay upon use of a perdeuteromethyl TMG{sub 3}tren isotopomer, d{sub 36}-1 (KIE = 24 at 25 C). The greatly enhanced thermal stability of d{sub 36}-1 allowed growth of diffraction quality crystals for which a high-resolution crystal structure was obtained. This structure showed an Fe=O unit (r = 1.661(2) {angstrom}) in the intended trigonal bipyramidal geometry enforced by the sterically bulky tetramethylguanidinyl donors of the tetradentate tripodal TMG{sub 3}tren ligand. The close proximity of the methyl substituents to the oxoiron unit yielded three symmetrically oriented short C-D {hor_ellipsis} O nonbonded contacts (2.38-2.49 {angstrom}), an arrangement that facilitated self-decay by rate-determining intramolecular hydrogen atom abstraction and subsequent formation of a ligand-hydroxylated iron(III) product. EPR and Moessbauer quantification of the various iron products, referenced against those obtained from reaction of 1 with 1,4-cyclohexadiene, allowed formulation of a detailed mechanism for the self-decay process. The solution of this first crystal structure of a high-spin (S = 2) oxoiron(IV) center represents a fundamental step on the path toward a full understanding of these pivotal biological intermediates.

  14. Department of Nuclear Radiospectroscopy - Overview

    International Nuclear Information System (INIS)

    Jasinski, A.

    2001-01-01

    Full text: Research at the Department of Nuclear Radiospectroscopy encompasses various aspects of nuclear magnetic resonance (NMR) and its applications to solids and to biosystems. Current research activity covers two areas: investigation of molecular dynamics and structures in solids using NMR spectroscopy, and examination of human organs, small animals and plants using MR imaging and localized spectroscopy. MAGNETIC RESONANCE IMAGING LABORATORY Biomedical applications of magnetic resonance imaging (MRI) and spectroscopy (MRS) together with development and modification of the existing hardware were our main topic of research in the year 2000. The following projects have been carried out: * Investigation of the water diffusion tensor in biological systems in vivo and in vitro; * Study of localized MR spectra in the skeletal muscles of the human limbs; * Structure and physiological processes of the tissue and organs in the normal and pathological state studied by MRI and MRS methods; * Generation of the magnetic field gradients and design of highly specialized RF coils for MR localized spectroscopy and MR Imaging. This work has been done in collaboration with Collegium Medicum of the Jagiellonian University and the Institute for Biodiagnostics in Winnipeg, Canada. As far as the hardware and the methodology side are concerned our, tasks in the year 2000 included: * Development and modifications of home-built MR Microscopy based on 8.4T magnet; * Modifications of the 4.7T magnet console; * Designing and optimizing the ergometer used in skeletal muscle research; * Implementation of the fast imaging methods based on the spin echo sequences. MAGNETIC RESONANCE LABORATORY Deuteron NMR spectroscopy was applied to the study of reorientational dynamics and tunnelling rotation of ammonium ion isotopomers. As particular achievements we point out results concerning structure refinement of structure, establishing the symmetry of the rotational potential, and detection of the

  15. Revisiting the metathesis of 13C-monolabeled ethane

    KAUST Repository

    Maury, Olivier; Lefort, Laurent; Vidal, Vé ronique; Thivolle-Cazat, Jean; Basset, Jean-Marie

    2010-01-01

    The metathesis of 13C-monolabeled ethane leads to the parallel occurrence of degenerate and productive reactions, affording the statistical distribution of the various product isotopomers, which can be rationalized in terms of a mechanistic reaction

  16. TROSY of side-chain amides in large proteins

    Science.gov (United States)

    Liu, Aizhuo; Yao, Lishan; Li, Yue; Yan, Honggao

    2012-01-01

    By using the mixed solvent of 50% H2O/50% D2O and employing deuterium decoupling, TROSY experiments exclusively detect NMR signals from semideuterated isotopomers of carboxamide groups with high sensitivities for proteins with molecular weights up to 80 kDa. This isotopomer-selective strategy extends TROSY experiments from exclusively detecting backbone to both backbone and side-chain amides, particularly in large proteins. Because of differences in both TROSY effect and dynamics between 15N–HE{DZ} and 15N–HZ{DE} isotopomers of the same carboxamide, the 15N transverse magnetization of the latter relaxes significantly faster than that of the former, which provides a direct and reliable stereospecific distinction between the two configurations. The TROSY effects on the 15N–HE{DZ} isotopomers of side-chain amides are as significant as on backbone amides. PMID:17347000

  17. Department of Nuclear Radiospectroscopy - Overview

    International Nuclear Information System (INIS)

    Jasinski, A.

    1999-01-01

    Research at the Department of Nuclear Radiospectroscopy concerns various aspects of the NMR and its applications to solids and to biosystems. The research activity covers: investigation of molecular dynamics and structures in solids using NMR spectroscopy, and investigation of humans, animals and plants using NMR imaging and localized spectroscopy. The MR Laboratory is equipped with a 7.05 T wide bore vertical superconducting magnet (SCM) with a pulse spectrometer. It allows to measure of deuteron NMR spectra at T ≥ 5 K. NMR high resolution spectra for 29 Si, 11 B, 27 Al and 31 P nuclei can be measured using MAS-NMR probe heads. The Magnetic Resonance Imaging Laboratory is equipped with 360 MHz MR microscope based on a 8.4 T narrow bore SCM and a MRI/MRS system based on a 2 T, 31 cm horizontal bore SCM. Magnetic Resonance Laboratory: Molecular reorientation studies aimed at disclosing tunnelling rotation and structural research of amorphous solids were main topics. Realisation of these projects required a development of our NMR pulse spectrometer and theoretical methods. The spectrometer was put into operation in 1997. Recent development was done in the data acquisition by the introduction of a new A/D converter and a pulse programmer. Tunnelling and reorientations of mixed isotope rotors are currently the most interesting topics. For a given deuteration rate of an ammonium compound it was anticipating that deuteron NMR spectra consist of weighted contributions from the following isotopomers: NH 3 D + , NH 2 D 2 + , NH 3 D + and ND 4 + . Each isotopomer provides a characteristic spectral component due to its mobility. Measurements were performed for a number of partially deuterated samples of (NH 4 ) 2 S 2 O 8 , NH 4 ClO 4 , NH 4 PF 6 , (NH 4 ) 2 ZnCl 4 and (NH 4 ) 2 TeCl 6 in the T = 5-100 K. The spectra of NH 3 D + ions are particularly interesting. A new effect of an isotope ordering was observed. The structural investigations of amorphous solids by NMR

  18. Low cost production of perdeuterated biomass using methylotrophic yeasts

    International Nuclear Information System (INIS)

    Haon, S.; Auge, S.; Tropis, M.; Milon, A.; Lindley, N.D.

    1993-01-01

    Three strains of methylotropic yeasts, Candida boidinii, Pichia angusta (previously Hansenula polymorpha) and Pichia pastoris, were studied for their capacity to grow on methanol in deuterated media. Growth rates, determined relative to the extent of deuteration of water and/or methanol, showed that water deuteration was the major limiting factor. After adaptation to deuterium by progressive transfer through media of increasing deuteration, growth rates were diminished relative to those obtained on hydrogenated media of identical salts composition: the two Pichia species retained the highest growth rates in the full deuterated medium. Perdeuterated biomass (16 g) was obtained in a 1 liter fed-batch fermentation and the extent of deuteration of isolated ergosterol has been shown to be 97.5% by mass spectrometric analysis. (Author)

  19. 77 FR 19648 - Marine Mammals; File No. 16094

    Science.gov (United States)

    2012-04-02

    ... measured; have biological samples collected (blood, milk (lactating females), blubber, skin, muscle, hair, mucus membrane swabs, stomach lavage, tooth and vibrissae); be administered deuterated water; have...

  20. Molecular Structures, Vibrational Spectroscopy, and Normal-Mode Analysis of M(2)(C&tbd1;CR)(4)(PMe(3))(4) Dimetallatetraynes. Observation of Strongly Mixed Metal-Metal and Metal-Ligand Vibrational Modes.

    Science.gov (United States)

    John, Kevin D.; Miskowski, Vincent M.; Vance, Michael A.; Dallinger, Richard F.; Wang, Louis C.; Geib, Steven J.; Hopkins, Michael D.

    1998-12-28

    The nature of the skeletal vibrational modes of complexes of the type M(2)(C&tbd1;CR)(4)(PMe(3))(4) (M = Mo, W; R = H, Me, Bu(t)(), SiMe(3)) has been deduced. Metrical data from X-ray crystallographic studies of Mo(2)(C&tbd1;CR)(4)(PMe(3))(4) (R = Me, Bu(t)(), SiMe(3)) and W(2)(C&tbd1;CMe)(4)(PMe(3))(4) reveal that the core bond distances and angles are within normal ranges and do not differ in a statistically significant way as a function of the alkynyl substituent, indicating that their associated force constants should be similarly invariant among these compounds. The crystal structures of Mo(2)(C&tbd1;CSiMe(3))(4)(PMe(3))(4) and Mo(2)(C&tbd1;CBu(t)())(4)(PMe(3))(4) are complicated by 3-fold disorder of the Mo(2) unit within apparently ordered ligand arrays. Resonance-Raman spectra ((1)(delta-->delta) excitation, THF solution) of Mo(2)(C&tbd1;CSiMe(3))(4)(PMe(3))(4) and its isotopomers (PMe(3)-d(9), C&tbd1;CSiMe(3)-d(9), (13)C&tbd1;(13)CSiMe(3)) exhibit resonance-enhanced bands due to a(1)-symmetry fundamentals (nu(a) = 362, nu(b) = 397, nu(c) = 254 cm(-)(1) for the natural-abundance complex) and their overtones and combinations. The frequencies and relative intensities of the fundamentals are highly sensitive to isotopic substitution of the C&tbd1;CSiMe(3) ligands, but are insensitive to deuteration of the PMe(3) ligands. Nonresonance-Raman spectra (FT-Raman, 1064 nm excitation, crystalline samples) for the Mo(2)(C&tbd1;CSiMe(3))(4)(PMe(3))(4) compounds and for Mo(2)(C&tbd1;CR)(4)(PMe(3))(4) (R = H, D, Me, Bu(t)(), SiMe(3)) and W(2)(C&tbd1;CMe)(4)(PMe(3))(4) exhibit nu(a), nu(b), and nu(c) and numerous bands due to alkynyl- and phosphine-localized modes, the latter of which are assigned by comparisons to FT-Raman spectra of Mo(2)X(4)L(4) (X = Cl, Br, I; L = PMe(3), PMe(3)-d(9))(4) and Mo(2)Cl(4)(AsMe(3))(4). Valence force-field normal-coordinate calculations on the model compound Mo(2)(C&tbd1;CH)(4)P(4), using core force constants transferred from a calculation

  1. Body composition using deuterated water, index of insulin resistance and cortisol levels in Costa Rican school in the metropolitan area; Composicion corporal utilizando agua deuterada, indice de resistencia a la insulina y niveles de cortisol en escolares costarricenses del area metropolitana

    Energy Technology Data Exchange (ETDEWEB)

    Valverde Vindas, Allan Ignacio

    2014-07-01

    Body composition in the Costa Rican child population is evaluated and analyzed to determine the relationship with the index of insulin resistance and serum cortisol levels. 113 children in the metropolitan area were studied using deuterium isotope techniques as reference method for overweight and obesity. Morning cortisol levels were determined by immunoassay techniques (ELISA). The insulin resistance index of 113 Costa Rican boys and girls is obtained by the homeostatic method and the relationship between body composition with index of insulin resistance or levels of cortisol [Spanish] La composicion corporal en la poblacion infantil costarricense es evaluada y analizada para determinar la relacion con el indice de resistencia a la insulina y niveles de cortisol serico. 113 ninos y ninas del area metropolitana fueron estudiados utilizando tecnicas isotopicas de deuterio como metodo de referencia para sobrepeso y obesidad. Los niveles de cortisol matutino se han determinado mediante tecnicas inmunoensayo (ELISA). El indice resistencia a la insulina de 113 ninos y ninas costarricenses es obtenido mediante el metodo homeostatico asi como la relacion entre composicion corporal con indice de resistencia a la insulina o niveles de cortisol.

  2. Isotopic analysis of H{sub 2}, HD, D{sub 2} mixtures and analysis of ortho-para-hydrogen mixtures by gas chromatography; Dosages par chromatographie en phase gazeuse de melanges d'hydrogene, d'hydrogene deutere, de deuterium et de melanges ortho-para-hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Botter, F; Perriere, G de la; Tistchenko, S [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1961-07-01

    This communication describes the present situation concerning the possibilities of vapor phase chromatography for the separation and analysis of mixtures of H{sub 2}, HD and D{sub 2} and of ortho- and para-hydrogen mixtures. Separation factors for physical adsorption of the various varieties of hydrogen have been deduced from chromatograms and have also been measured directly with a static method - the agreements is good. (author) [French] Le present rapport decrit diverses possibilites qu'offre la chromatographie gazeuse d'elution en ce qui concerne le dosage des melanges H{sub 2}, HD, D{sub 2} et des varietes ortho et para de l'hydrogene. On a calcule, a partir des chromatogrammes obtenus, les facteurs de separation par adsorption physique des differentes varietes d'hydrogene, et compare aux facteurs de separation determines par mesure directe. (auteur)

  3. Deuterium labelling of tryptamine, serotonin and their N-methylated metabolites using solvent exchange reactions

    Energy Technology Data Exchange (ETDEWEB)

    Raeisaenen, M; Kaerkkaeinen, J [Helsinki Univ. (Finland). Dept. of Medical Chemistry

    1979-01-01

    Technically uncomplicated methods based on catalytic isotope exchange in deuterated solvents are described for the deuteration of tryptamine, serotonin and their N-methylated metabolites. Heterogeneous platinum catalysis, homogeneous acid catalysis and their combination have been employed. The properties of the labelled derivatives prepared with each technique as well as their use in mass spectrometric work are discussed.

  4. On a possibility of cold fusion in deuterium-saturated YBa2Cu3O7-x ceramics in superconducting state

    International Nuclear Information System (INIS)

    Lipson, A.G.; Sakov, D.M.; Toporov, Yu.P.; Gromov, V.V.; Deryagin, B.V.

    1991-01-01

    A possibility to generate neutrons by deuterated YBa 2 Cu 3 O 7-x ceramics in superconducting (T c ) and normal (T>T c ) states is studied. The presented data points to a relationship between the processes of cold nuclear fusion and high-temperature superconductivity in YBa 2 Cu 3 O 7-x pellets deuterated at T c (77< T<90 K)

  5. Infrared and Raman spectra of uric acid and its 15N and D labelled compounds

    International Nuclear Information System (INIS)

    Majoube, Michel

    Infrared and Raman spectra of polycrystalline uric acid (2, 6, 8-trioxypurine) 1.3, 7 and 9- 15 N and deuterated analogues have been determined. Band shifts with 15 N substitution and with deuteration are discussed. An assignment of fundamental vibrations of uric acid is proposed from the comparison of the eight isotopically substituted analogues [fr

  6. Elucidation of density profile of self-assembled sitosterol + oryzanol tubules with small-angle neutron scattering

    NARCIS (Netherlands)

    Bot, A.; Gilbert, E.P.; Bouwman, W.G.; Sawalha, H.I.M.; Adel, den R.; Garamus, V.M.; Venema, P.; Linden, van der E.; Flöter, E.

    2012-01-01

    Small-angle neutron scattering (SANS) experiments have been performed on self-assembled tubules of sitosterol and oryzanol in triglyceride oils to investigate details of their structure. Alternative organic phases (deuterated and non-deuterated decane, limonene, castor oil and eugenol) were used to

  7. Solubility of Lead Sulfate in Water and in Sodium Sulfate Solutions: An Experiment in Atomic Absorption Spectrophotometry.

    Science.gov (United States)

    Lehman, Thomas A.; Everett, Wayne W.

    1982-01-01

    Describes a set of undergraduate laboratory experiments which provide experience in deuteration and derivatization procedures applied to infrared spectroscopy. Basic skills in vacuum-line technique are also taught while measuring infrared spectra of deuterated solid samples and demonstrating the value of derivatization as an aid to interpreting…

  8. Ideal gas thermodynamic properties for the phenyl, phenoxy, and o-biphenyl radicals

    Science.gov (United States)

    Burcat, A.; Zeleznik, F. J.; Mcbride, B. J.

    1985-01-01

    Ideal gas thermodynamic properties of the phenyl and o-biphenyl radicals, their deuterated analogs and the phenoxy radical were calculated to 5000 K using estimated vibrational frequencies and structures. The ideal gas thermodynamic properties of benzene, biphenyl, their deuterated analogs and phenyl were also calculated.

  9. Deuterium labelling of tryptamine, serotonin and their N-methylated metabolites using solvent exchange reactions

    International Nuclear Information System (INIS)

    Raeisaenen, M.; Kaerkkaeinen, J.

    1979-01-01

    Technically uncomplicated methods based on catalytic isotope exchange in deuterated solvents are described for the deuteration of tryptamine, serotonin and their N-methylated metabolites. Heterogeneous platinum catalysis, homogeneous acid catalysis and their combination have been employed. The properties of the labelled derivatives prepared with each technique as well as their use in mass spectrometric work are discussed. (author)

  10. Synthesis of deuterium-labeled plant sterols and analysis of their side-chain mobility by solid state deuterium NMR

    International Nuclear Information System (INIS)

    Marsan, M.P.; Muller, I.; Milon, A.

    1996-01-01

    Sitosterol and stigmasterol, plant sterols, were deuterated at specific positions. Orientation and mobility of the deuterated sitosterol and stigmasterol (and two of their diasteromers) on oriented lipid bilayers were analyzed by deuterium NMR spectroscopy. Orientation and mobility of the side chains was revealed by these studies

  11. Neutron interrogation systems using pyroelectric crystals and methods of preparation thereof

    Science.gov (United States)

    Tang, Vincent; Meyer, Glenn A.; Falabella, Steven; Guethlein, Gary; Rusnak, Brian; Sampayan, Stephen; Spadaccini, Christopher M.; Wang, Li-Fang; Harris, John; Morse, Jeff

    2017-08-01

    According to one embodiment, an apparatus includes a pyroelectric crystal, a deuterated or tritiated target, an ion source, and a common support coupled to the pyroelectric crystal, the deuterated or tritiated target, and the ion source. In another embodiment, a method includes producing a voltage of negative polarity on a surface of a deuterated or tritiated target in response to a temperature change of a pyroelectric crystal, pulsing a deuterium ion source to produce a deuterium ion beam, accelerating the deuterium ion beam to the deuterated or tritiated target to produce a neutron beam, and directing the ion beam onto the deuterated or tritiated target to make neutrons using a voltage of the pyroelectric crystal and/or an HGI surrounding the pyroelectric crystal. The directionality of the neutron beam is controlled by changing the accelerating voltage of the system. Other apparatuses and methods are presented as well.

  12. Quantitative analysis of deuterium using the isotopic effect on quaternary {sup 13}C NMR chemical shifts

    Energy Technology Data Exchange (ETDEWEB)

    Darwish, Tamim A., E-mail: tamim.darwish@ansto.gov.au [National Deuteration Facility, Australian Nuclear Science and Technology Organisation, Locked Bag 21, Kirrawee DC, NSW 2232 (Australia); Yepuri, Nageshwar Rao; Holden, Peter J. [National Deuteration Facility, Australian Nuclear Science and Technology Organisation, Locked Bag 21, Kirrawee DC, NSW 2232 (Australia); James, Michael [Australian Synchrotron, 800 Blackburn Road, Clayton, Victoria 3168 (Australia)

    2016-07-13

    Quantitative analysis of specifically deuterated compounds can be achieved by a number of conventional methods, such as mass spectroscopy, or by quantifying the residual {sup 1}H NMR signals compared to signals from internal standards. However, site specific quantification using these methods becomes challenging when dealing with non-specifically or randomly deuterated compounds that are produced by metal catalyzed hydrothermal reactions in D{sub 2}O, one of the most convenient deuteration methods. In this study, deuterium-induced NMR isotope shifts of quaternary {sup 13}C resonances neighboring deuterated sites have been utilized to quantify the degree of isotope labeling of molecular sites in non-specifically deuterated molecules. By probing {sup 13}C NMR signals while decoupling both proton and deuterium nuclei, it is possible to resolve {sup 13}C resonances of the different isotopologues based on the isotopic shifts and the degree of deuteration of the carbon atoms. We demonstrate that in different isotopologues, the same quaternary carbon, neighboring partially deuterated carbon atoms, are affected to an equal extent by relaxation. Decoupling both nuclei ({sup 1}H, {sup 2}H) resolves closely separated quaternary {sup 13}C signals of the different isotopologues, and allows their accurate integration and quantification under short relaxation delays (D1 = 1 s) and hence fast accumulative spectral acquisition. We have performed a number of approaches to quantify the deuterium content at different specific sites to demonstrate a convenient and generic analysis method for use in randomly deuterated molecules, or in cases of specifically deuterated molecules where back-exchange processes may take place during work up. - Graphical abstract: The relative intensities of quaternary {sup 13}C {"1H,"2H} resonances are equal despite the different relaxation delays, allowing the relative abundance of the different deuterated isotopologues to be calculated using NMR fast

  13. Proceedings of the U.S. Army Chemical Research, Development and Engineering Center Scientific Conference on Chemical Defense Research Held in Aberdeen Proving Ground, Maryland on 14-17 November 1989

    Science.gov (United States)

    1990-08-01

    functionalities similar to sugars (hydroxyacetaldehyde, hydroxymethyl ether, ethylene glycol and dimethyl ether) and sugars with 3 carbon atoms (D-glyceraldehyde...like molecules studied were isotopomers of hydroxyacetaldehyde, hydroxymethyl ether, ethylene glycol and dimethyl ether. Calculated frequencies...Vol. I, 1979. 3. Qualye, O.R., and Norton, H.M., The Mechanism of Esterification of Strong Acids. The Esterification of Neopentyl Alcohol with

  14. Energy transfer properties and mechanisms

    International Nuclear Information System (INIS)

    1991-01-01

    This report discusses the energy transfer mechanisms in azulene, benzene, toluene, and isotopomers. Also discussed is the coupled energy reservoirs model, quantum effects in energy transfer, NO 2 energy transfer, densities of states, the reactant states model, and O 3 excited electronic states

  15. Acute inhibition of hepatic glucose-6-phosphatase does not affect gluconeogenesis but directs gluconeogenic flux toward glycogen in fasted rats. A pharmacological study with the chlorogenic acid derivative S4048

    NARCIS (Netherlands)

    van Dijk, T. H.; van der Sluijs, F. H.; Wiegman, C. H.; Baller, J. F.; Gustafson, L. A.; Burger, H. J.; Herling, A. W.; Kuipers, F.; Meijer, A. J.; Reijngoud, D. J.

    2001-01-01

    Effects of acute inhibition of glucose-6-phosphatase activity by the chlorogenic acid derivative S4048 on hepatic carbohydrate fluxes were examined in isolated rat hepatocytes and in vivo in rats. Fluxes were calculated using tracer dilution techniques and mass isotopomer distribution analysis in

  16. Acute inhibition of hepatic glucose-6-phosphatase does not affect gluconeogenesis but directs gluconeogenic flux toward glycogen in fasted rats - A pharmacological study with the chlorogenic acid derivative S4048

    NARCIS (Netherlands)

    van Dijk, TH; van der Sluijs, FH; Wiegman, CH; Baller, JFW; Gustafson, LA; Burger, HJ; Herling, AW; Kuipers, F; Meijer, AJ; Reijngoud, DJ

    2001-01-01

    Effects of acute inhibition of glucose-6-phosphatase activity by the chlorogenic acid derivative S4048 on hepatic carbohydrate fluxes were examined in isolated rat hepatocytes and in vivo in rats. Fluxes were calculated using tracer dilution techniques and mass isotopomer distribution analysis in

  17. Revisiting the metathesis of 13C-monolabeled ethane

    KAUST Repository

    Maury, Olivier

    2010-12-13

    The metathesis of 13C-monolabeled ethane leads to the parallel occurrence of degenerate and productive reactions, affording the statistical distribution of the various product isotopomers, which can be rationalized in terms of a mechanistic reaction scheme combining both processes. © 2010 American Chemical Society.

  18. The quantification of gluconeogenesis in healthy men by (2)H2O and [2-(13)C]glycerol yields different results: rates of gluconeogenesis in healthy men measured with (2)H2O are higher than those measured with [2-(13)C]glycerol

    NARCIS (Netherlands)

    Ackermans, M. T.; Pereira Arias, A. M.; Bisschop, P. H.; Endert, E.; Sauerwein, H. P.; Romijn, J. A.

    2001-01-01

    The quantification of gluconeogenesis (GNG) by (2)H2O and [2-(13)C]glycerol and the mass isotopomer dilution analysis of glucose does not involve assumptions regarding the enrichment of the oxaloacetate precursor pool. To compare these two methods we measured GNG in six healthy postabsorptive males

  19. Synthesis of seven deuteromethyl-caffeine analogues observation of deuterium isotope effects on CMR analysis

    Energy Technology Data Exchange (ETDEWEB)

    Falconnet, J.B.; Brazier, J.L.; Desage, M.

    1986-03-01

    The synthesis of all 7 N-trideuteromethyl isotopomers of caffeine by reaction of trideuteromethyl iodide (C/sup 2/H/sub 3/I) with the appropriate xanthine molecules is described. The use of proton, deuterium and carbon-13-NMR as a first step in purity assessment revealed /sup 13/C-NMR deuterium isotope effects on the resonance of perdeuteromethyl carbons.

  20. Low energy acetoin ions CH3C(=O)C(H)(OH)CH3.+ decompose to CH3CO. and CH3CHOH+ via a remarkable "hidden rearrangement"

    Science.gov (United States)

    Suh, Dennis; Burgers, Peter C.; Terlouw, Johan K.

    1995-06-01

    Tandem mass spectrometry based experiments on D and 18O labelled acetoin isotopomers show that the title reaction is not just a simple bond cleavage, but rather involves rearrangement via ion--dipole complexes; the intermediacy of a charge-transfer complex is proposed to account for the observed product ratios.

  1. Double hydrogen atom transfer in lactamide radical cations via ion-neutral complexes

    Science.gov (United States)

    Friedrichs, Heike; McGibbon, Graham A.; Schwarz, Helmut

    1996-02-01

    Tandem mass spectrometry experiments on lactamide and deuterium-labelled isotopomers show that the reaction of metastable ions CH3CH(OH)CONH2·+ --> CH3CO· + HC(OH)NH2+ occurs via ion-neutral complexes. The experimental findings are complemented by density functional theory calculations.

  2. Mechanism and Stereoselectivity of Zeolite-catalysed Sugar Isomerisation in Alcohols

    DEFF Research Database (Denmark)

    Shunmugavel, Saravanamurugan; Riisager, Anders; Taarning, Esben

    2016-01-01

    Glucose isomerisation to fructose can occur by different pathways and the mechanism of zeolite-catalysed glucose isomerisation in methanol has remained incompletely understood. Herein, the mechanism is studied using an 1H-13C HSQC NMR assay resolving different fructose isotopomers. We find that z...

  3. The synthesis of (-)-4-methyl-8-chloro-trans-1,2,3,4,4a,5,6,10b-octahydrobenzo-[f]-quinolin-3-one-[3-14C] (LY300502-[14C]) via a circuitous route

    International Nuclear Information System (INIS)

    Fengjiun Kuo; Wheeler, W.J.

    1994-01-01

    The synthesis of the C-14 labeled isotopomer of LY300502, a potent 5α-reductase inhibitor has been accomplished in four radiochemical steps. The route involves the synthesis of LY300502-[ 14 C] from LY300502 via a circuitous route; the label was introduced with ethyl chloroformate-[carbonyl- 14 C]. (author)

  4. Isotope-selective ionization using four-pulse alignment

    International Nuclear Information System (INIS)

    Akagi, Hiroshi; Kasajima, Tatsuya; Kumada, Takayuki; Itakura, Ryuji; Yokoyama, Atsushi; Hasegawa, Hirokazu; Ohshima, Yasuhiro

    2013-01-01

    We have proposed a laser isotope separation method utilizing molecular alignment and non-resonant multiphoton ionization, and demonstrated isotope-selective ionization of 14 N 2 and 15 N 2 isotopomers, using one-pulse alignment. In the present work, we used a train of four identical pulses, instead of one pulse, to obtain the higher selectivity. (author)

  5. Modeling Method for Increased Precision and Scope of Directly Measurable Fluxes at a Genome-Scale

    DEFF Research Database (Denmark)

    McCloskey, Douglas; Young, Jamey D.; Xu, Sibei

    2016-01-01

    pathways of traditional MFA models and also covers the additional pathways of purine, pyrimidine, isoprenoid, methionine, riboflavin, coenzyme A, and folate, as well as other biosynthetic pathways. When evaluating the iDM2014 using a set of measured intracellular intermediate and cofactor mass isotopomer...

  6. Stable isotope-resolved analysis with quantitative dissolution dynamic nuclear polarization

    DEFF Research Database (Denmark)

    Lerche, Mathilde Hauge; Yigit, Demet; Frahm, Anne Birk

    2018-01-01

    Metabolite profiles and their isotopomer distributions can be studied non-invasively in complex mixtures with NMR. The advent of dissolution Dynamic Nuclear Polarization (dDNP) and isotope enrichment add sensitivity and resolution to such met-abolic studies. Metabolic pathways and networks can be...

  7. Isotope effects on chemical shifts in tautomeric systems with double proton transfer. Citronin

    International Nuclear Information System (INIS)

    Hansen, P.E.; Langgard, M.; Bolvig, S.

    1998-01-01

    Primary and secondary deuterium isotope effects on 1 H and 13 C chemical shifts are measured in citrinin, a tautomeric compound with an unusual doubly intramolecularly hydrogen bonded structure. The isotope effects are to a large extent dominated by equilibrium contributions and deuteration leads to more of the deuterated enol forms rather than the deuterated acid form. 1 H 13 C and 17 O nuclear shieldings are calculated using density functional ab initio methods. A very good correlation between calculated nuclear shieldings and experimental 1 H and 13 C chemical shifts is obtained. The tautomeric equilibrium can be analyzed based on the isotope effects on B-6 and C-8 carbons and shows an increase in the o-quinone form on lowering the temperature. Furthermore, upon deuteration the largest equilibrium shift is found for deuteration at OH-8 and the shift in the tautomeric equilibrium upon deuteration at OH-8 and the shift in the tautomeric equilibrium upon deuteration is increasing at lower temperature. (author)

  8. organochlorine pesticides and degradation products in soil around

    African Journals Online (AJOL)

    dell

    quantification criteria included confirmation ... blanks. Recoveries of 13C-labelled and deuterated internal standards varied between. 69% and 119% ... 6–18%. The detection limit was defined as ... detection and every signal below this limit.

  9. Ultra-high-pressure liquid chromatography tandem mass spectrometry method for the determination of 9 organophosphate flame retardants in water samples

    NARCIS (Netherlands)

    Lorenzo, M.; Campo, J.; Picó, Y.

    2016-01-01

    Few methods are available for comprehensive organophosphate flame retardants (PFRs) detection in water and wastewater. Gas chromatography has been employed previously, but this approach is less selective, not amenable for use with deuterated standards and can suffer unfavorable fragmentation.

  10. Excited state intramolecular charge transfer reaction in 4-(1 ...

    Indian Academy of Sciences (India)

    Administrator

    cal reactions to the determination of paleotempera- tures from isotopic ... ordered liquid than H2O due to stronger H-bond in- teractions in the deuterated water ... layer chromatography and monitoring the excitation wavelength dependence of ...

  11. High-accuracy determination for optical indicatrix rotation in ferroelectric DTGS

    OpenAIRE

    O.S.Kushnir; O.A.Bevz; O.G.Vlokh

    2000-01-01

    Optical indicatrix rotation in deuterated ferroelectric triglycine sulphate is studied with the high-accuracy null-polarimetric technique. The behaviour of the effect in ferroelectric phase is referred to quadratic spontaneous electrooptics.

  12. Thermodynamics of TMPC/PSd/Fullerene Nanocomposites: SANS Study

    KAUST Repository

    Chua, Yang-Choo; Chan, Alice; Wong, Him-Cheng; Higgins, Julia S.; Cabral, João T.

    2010-01-01

    ) analysis demonstrate that 1-2 mass % of C60 fullerenes destabilizes a highly interacting mixture of poly(tetramethyl bisphenol A polycarbonate) and deuterated polystyrene (TMPC/PSd). We unequivocally corroborate these findings with time-resolved temperature

  13. Rovibrational spectra of DCF3 in the 2000 cm−1 region: A high-resolution study of the v5 = 2 and v2 = v5 = 1 levels

    Czech Academy of Sciences Publication Activity Database

    Ceausu-Velcescu, A.; Pracna, Petr; Predoi-Cross, A.

    2014-01-01

    Roč. 305, NOV 2014 (2014), s. 1-9 ISSN 0022-2852 Institutional support: RVO:61388955 Keywords : deuterated fluoroform * overtone bands * combination bands Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.482, year: 2014

  14. Rovibrational spectra of DCF3 in the 1900 cm(-)1 region: High-resolution study of the v(3) = v(4)=1/v(3)=2, v(6)=1 Fermi-interacting levels

    Czech Academy of Sciences Publication Activity Database

    Ceausu-Velcescu, A.; Pracna, Petr

    2014-01-01

    Roč. 295, JAN 2014 (2014), s. 31-36 ISSN 0022-2852 Institutional support: RVO:61388955 Keywords : deuterated fluoroform * combination bands * Fermi interaction Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.482, year: 2014

  15. Neutron scattering for the analysis of biological structures. Brookhaven symposia in biology. Number 27

    Energy Technology Data Exchange (ETDEWEB)

    Schoenborn, B P [ed.

    1976-01-01

    Sessions were included on neutron scattering and biological structure analysis, protein crystallography, neutron scattering from oriented systems, solution scattering, preparation of deuterated specimens, inelastic scattering, data analysis, experimental techniques, and instrumentation. Separate entries were made for the individual papers.

  16. The adaptation of methods in multilayer optics for the calculation of specular neutron reflection

    International Nuclear Information System (INIS)

    Penfold, J.

    1988-10-01

    The adaptation of standard methods in multilayer optics to the calculation of specular neutron reflection is described. Their application is illustrated with examples which include a glass optical flat and a deuterated Langmuir-Blodgett film. (author)

  17. Use of stable isotopes for the in vivo study of metabolic disorders

    International Nuclear Information System (INIS)

    Faull, K.F.; Gan, I.; Halpern, B.; Danke, D.M.

    1975-01-01

    Deuterated tyrosine has been used to study tyrosine metabolism in one normal and two tyrosinemic patients. The labeled tyrosine was ingested orally, after which urine and serum samples were examined at regular intervals for residual labeled tyrosine and tyrosine metabolites. Deuteration measurements were made with a combined GC-MS instrument operating under computer control using time averaging and mass fragmentometry. Initial experiments were done with a loading of 829 μmoles of deuterated tyrosine/kg body wt., but we have been able to reduce this by one-third without any loss of precision. The rate of deuterated tyrosine metabolism has allowed us to distinguish between individuals having different clinical manifestations but similar biochemical abnormalities. The sensitivity of the method suggests the procedure has value in the study of metabolic defects

  18. Solid Polarized Targets and Applications

    International Nuclear Information System (INIS)

    Crabb, D. G.

    2008-01-01

    Examples are given of dynamically polarized targets in use today and how the subsystems have changed to meet the needs of todays experiments. Particular emphasis is placed on target materials such as ammonia and lithium deuteride. Recent polarization studies of irradiated materials such as butanol, deuterated butanol, polyethylene, and deuterated polyethylene are presented. The operation of two non-DNP target systems as well as applications of traditional DNP targets are briefly discussed

  19. Minute Impurities Contribute Significantly to Olfactory Receptor Ligand Studies: Tales from Testing the Vibration Theory

    OpenAIRE

    Paoli, M.; M?nch, D.; Haase, A.; Skoulakis, E.; Turin, L.; Galizia, C. G.

    2017-01-01

    Several studies have attempted to test the vibrational hypothesis of odorant receptor activation in behavioral and physiological studies using deuterated compounds as odorants. The results have been mixed. Here, we attempted to test how deuterated compounds activate odorant receptors using calcium imaging of the fruit fly antennal lobe. We found specific activation of one area of the antennal lobe corresponding to inputs from a specific receptor. However, upon more detailed analysis, we disco...

  20. Photoconductivity and bleaching of trapped electrons at 770C in irradiated methylcyclohexane

    International Nuclear Information System (INIS)

    Dolivo, G.; Gaeumann, T.

    1977-01-01

    The influence of the wavelength and intensity of the bleaching radiation on the thermoluminescence, thermoconductivity, optical absorption and photoconductivity of the methylcyclohexane, protonated and deuterated, was studied. The energy level scheme of the trapped electron in this alkane is very similar to that found in MTHF and 3-MP. The rate of bleaching of the trapped electrons is less in the deuterated product. (U.K.)

  1. Preparation of paraherquamide labeled with deueterium or tritium

    Energy Technology Data Exchange (ETDEWEB)

    Blizzard, T.A.; Rosegay, A.; Mrozik, H.; Fisher, M.H. (Merck Sharp and Dohme Research Labs., Rahway, NJ (United States))

    1990-04-01

    Deprotonation of paraherquamide (1a) at C-24 and subsequent deuteration (or tritiation) is described. The procedure afforded 24-[sup 2]H-paraherquamide (1b) with 66% deuterium incorporation at C-24. Modification of the deuteration procedure to allow the introduction of tritium resulted in the preparation of 24-[sup 3]H-paraherquamide (1c) with specific activity 3.7Ci/mmol. (author).

  2. Small angle scattering from soft matter-application to complex mixed systems

    International Nuclear Information System (INIS)

    Boue, F.; Cousin, F.; Gummel, J.; Carrot, G.; El Harrak, A.; Oberdisse, J.

    2007-01-01

    The advantage of small angle neutron scattering associated with isotopic labelling through deuteration is illustrated in the case of mixed systems, created by associating already well-known systems of characteristic structures; this is also important for applications. Our first mixed system associates charged polymer chains, polyelectrolyte (here polystyrene sulfonate, PSS), with oppositely charged particles, proteins (here lysozyme). Different fractions of deuterated water (D 2 O) mixed with normal water are used to match the scattering length density of the protein or of the polymer in non-deuterated or deuterated version. First, this allows us to separate the protein and the polymer signal: we can then distinguish a case where the structures of each species alone in water are hardly modified by mixing, except for interconnections yielding a gel, and a case inducing complete change into a structure common to both species, made of aggregated globules. Secondly, using, for counter-ions of the poly-ions, deuterated Tetramethylammonium, together with matching both protein and polymer, we establish unambiguously the counter-ion release into the solvent. Thirdly, matching only a fraction of polymer chains, the other being deuterated, we extrapolate at zero deuterated fraction their form factor and describe the chain conformation inside the complexes. Fourthly, we illustrate the possibilities of modelling the signal on a second example of mixed system: a nano-composite made of silica particles surrounded by polymer dispersed into a deuterated polymer matrix. Chains are then visible in such reinforced polymer system, in particular when it is submitted to elongation: we discuss a possible model for an ideal system, introducing the scattering contribution from deformed chains. (authors)

  3. Synthesis of deuterium and tritium labelled tyrosine

    International Nuclear Information System (INIS)

    Kanska, M.; Drabarek, S.

    1980-01-01

    A new method of synthesis of tyrosine labelled with deuterium and tritium in the aromatic ring has been developed. Deuterated and tritiated tyrosine was obtained by isotope exchange between tyrosine and deuterated or tritiated water at elevated temperature in hydrochloric acid medium using K 2 PtCl 4 as a catalyst. For synthesis of tritiated tyrosine 1 Ci HTO was used; the specific activity of the product was 5 mCi/mMol. (author)

  4. Small angle scattering from soft matter-application to complex mixed systems; Diffusion de neutrons aux petits angles par la matiere molle-application aux systemes mixtes

    Energy Technology Data Exchange (ETDEWEB)

    Boue, F.; Cousin, F.; Gummel, J.; Carrot, G.; El Harrak, A. [CEA Saclay, Lab. Leon Brillouin, CNRS, 91 - Gif-sur-Yvette (France); Oberdisse, J. [Montpellier-2 Univ., Lab. des Colloides, Verres et Nanomateriaux, UMR 5587, 34 (France)

    2007-09-15

    The advantage of small angle neutron scattering associated with isotopic labelling through deuteration is illustrated in the case of mixed systems, created by associating already well-known systems of characteristic structures; this is also important for applications. Our first mixed system associates charged polymer chains, polyelectrolyte (here polystyrene sulfonate, PSS), with oppositely charged particles, proteins (here lysozyme). Different fractions of deuterated water (D{sub 2}O) mixed with normal water are used to match the scattering length density of the protein or of the polymer in non-deuterated or deuterated version. First, this allows us to separate the protein and the polymer signal: we can then distinguish a case where the structures of each species alone in water are hardly modified by mixing, except for interconnections yielding a gel, and a case inducing complete change into a structure common to both species, made of aggregated globules. Secondly, using, for counter-ions of the poly-ions, deuterated Tetramethylammonium, together with matching both protein and polymer, we establish unambiguously the counter-ion release into the solvent. Thirdly, matching only a fraction of polymer chains, the other being deuterated, we extrapolate at zero deuterated fraction their form factor and describe the chain conformation inside the complexes. Fourthly, we illustrate the possibilities of modelling the signal on a second example of mixed system: a nano-composite made of silica particles surrounded by polymer dispersed into a deuterated polymer matrix. Chains are then visible in such reinforced polymer system, in particular when it is submitted to elongation: we discuss a possible model for an ideal system, introducing the scattering contribution from deformed chains. (authors)

  5. New method for the study of Amaryllidaceae alkaloid biosynthesis using biotransformation of deuterium-labeled precursor in tissue cultures

    International Nuclear Information System (INIS)

    Tahchy, A. E.; Boisbrun, M.; Chretien, F.; Henry, M.; Chapleur, Y.; Laurain-Mattar, D.; Ptak, A.; Dupire, F.

    2010-01-01

    Biotransformation of deuterated-4'-O-methylnorbelladine into alkaloids galanthamine and lycorine in tissue cultures of Leucojum aestivum was demonstrated using HPLC coupled to mass spectrometry. GC-MS screening was also carried to investigate other native and deuterated alkaloids. A total of six labeled alkaloids were identified indicating that 4'-O-methyl-d3-norbelladine is incorporated into three different groups of Amaryllidaceae alkaloids that are biosynthesized by three modes of intramolecular oxidative phenol coupling. (authors)

  6. Effect of D2O on growth properties and chemical structure of annual ryegrass (Lolium multiflorum)

    Energy Technology Data Exchange (ETDEWEB)

    Evans, Barbara R [ORNL; Bali, Garima [Georgia Institute of Technology, Atlanta; Reeves, David T [ORNL; O' Neill, Hugh Michael [ORNL; Sun, Qining [Georgia Institute of Technology, Atlanta; Shah, Riddhi S [ORNL; Ragauskas, Arthur [Georgia Institute of Technology, Atlanta

    2014-01-01

    In present paper, we report the production and detailed structural analysis of deuterium-enriched rye grass (Lolium multiflorum) for neutron scattering experiments. An efficient method to produce deuterated biomass was developed by designing hydroponic perfusion chambers. In preliminary studies, the partial deuterated rye samples were grown in increasing levels of D2O to study the seed germination and the level of deuterium incorporation as a function of D2O concentration. Solution NMR method indicated 36.9 % deuterium incorporation in 50 % D2O grown annual rye samples and further significant increase in the deuterium incorporation level was observed by germinating the rye seedlings in H2O and growing in 50 % D2O inside the perfusion chambers. Moreover, in an effort to compare the substrate characteristics related to enzymatic hydrolysis on deuterated and protiated version of biomass, annual rye grown in 50 % D2O was selected for detailed biomass characterization studies. The compositional analyses, degree of polymerization and cellulose crystallinity were compared with its protiated control. The cellulose molecular weight indicated slight variation with deuteration; however, hemicellulose molecular weights and cellulose crystallinity remain unaffected with the deuteration. Besides the minor differences in biomass components, the development of deuterated biomass for neutron scattering application is essential to understand the complex biomass conversion processes.

  7. Dynamic analysis of CO₂ labeling and cell respiration using membrane-inlet mass spectrometry.

    Science.gov (United States)

    Yang, Tae Hoon

    2014-01-01

    Here, we introduce a mass spectrometry-based analytical method and relevant technical details for dynamic cell respiration and CO2 labeling analysis. Such measurements can be utilized as additional information and constraints for model-based (13)C metabolic flux analysis. Dissolved dynamics of oxygen consumption and CO2 mass isotopomer evolution from (13)C-labeled tracer substrates through different cellular processes can be precisely measured on-line using a miniaturized reactor system equipped with a membrane-inlet mass spectrometer. The corresponding specific rates of physiologically relevant gases and CO2 mass isotopomers can be quantified within a short-term range based on the liquid-phase dynamics of dissolved fermentation gases.

  8. Communication: On the isotope anomaly of nuclear quadrupole coupling in molecules

    Science.gov (United States)

    Filatov, Michael; Zou, Wenli; Cremer, Dieter

    2012-10-01

    The dependence of the nuclear quadrupole coupling constants (NQCC) on the interaction between electrons and a nucleus of finite size is theoretically analyzed. A deviation of the ratio of the NQCCs obtained from two different isotopomers of a molecule from the ratio of the corresponding bare nuclear electric quadrupole moments, known as quadrupole anomaly, is interpreted in terms of the logarithmic derivatives of the electric field gradient at the nuclear site with respect to the nuclear charge radius. Quantum chemical calculations based on a Dirac-exact relativistic methodology suggest that the effect of the changing size of the Au nucleus in different isotopomers can be observed for Au-containing molecules, for which the predicted quadrupole anomaly reaches values of the order of 0.1%. This is experimentally detectable and provides an insight into the charge distribution of non-spherical nuclei.

  9. Electron spray ionization mass spectrometry and 2D 31P NMR for monitoring 18O/16O isotope exchange and turnover rates of metabolic oligophosphates

    International Nuclear Information System (INIS)

    Nemutlu, Emirhan; Juranic, Nenad; Macura, Slobodan; Zhang, Song; Terzic, Andre; Dzeja, Petras P.; Ward, Lawrence E.; Dutta, Tumpa; Nair, K.S.

    2012-01-01

    A new method was here developed for the determination of 18 O-labeling ratios in metabolic oligophosphates, such as ATP, at different phosphoryl moieties (α-, β-, and γ-ATP) using sensitive and rapid electrospray ionization mass spectrometry (ESI-MS). The ESI-MS-based method for monitoring of 18 O/ 16 O exchange was validated with gas chromatography-mass spectrometry and 2D 31 P NMR correlation spectroscopy, the current standard methods in labeling studies. Significant correlation was found between isotopomer selective 2D 31 P NMR spectroscopy and isotopomer less selective ESI-MS method. Results demonstrate that ESI-MS provides a robust analytical platform for simultaneous determination of levels, 18 O-labeling kinetics and turnover rates of α-, β-, and γ-phosphoryls in ATP molecule. Such method is advantageous for large scale dynamic phosphometabolomic profiling of metabolic networks and acquiring information on the status of probed cellular energetic system. (orig.)

  10. Synthesis of isotopically labeled ketamine

    OpenAIRE

    Stuchlíková, Lucie

    2011-01-01

    In this work were synthesized ketamine isotopomers. Ketamine is used in human medicine and veterinary sectors. It has very broad spectrum of pharmacological effects: anesthetic, analgesic, hallucinogenic, bronchodilator, cardiovascular and antidepressive, which is currently in the research. At first was synthesized precursor of ketamine, N- desmethylketamine which was subsequently labeled the deuterium, tritium and carbon- 14. For the determination of purity and identity mass spectrometry and...

  11. Isotope chirality in long-armed multifunctional organosilicon ("Cephalopod") molecules.

    Science.gov (United States)

    Barabás, Béla; Kurdi, Róbert; Zucchi, Claudia; Pályi, Gyula

    2018-07-01

    Long-armed multifunctional organosilicon molecules display self-replicating and self-perfecting behavior in asymmetric autocatalysis (Soai reaction). Two representatives of this class were studied by statistical methods aiming at determination of probabilities of natural abundance chiral isotopomers. The results, reported here, show an astonishing richness of possibilities of the formation of chiral isotopically substituted derivatives. This feature could serve as a model for the evolution of biological chirality in prebiotic and early biotic stereochemistry. © 2018 Wiley Periodicals, Inc.

  12. Isotopic labelling studies for a gold-catalysed skeletal rearrangement of alkynyl aziridines

    Directory of Open Access Journals (Sweden)

    Neil Spencer

    2011-06-01

    Full Text Available Isotopic labelling studies were performed to probe a proposed 1,2-aryl shift in the gold-catalysed cycloisomerisation of alkynyl aziridines into 2,4-disubstituted pyrroles. Two isotopomers of the expected skeletal rearrangement product were identified using 13C-labelling and led to a revised mechanism featuring two distinct skeletal rearrangements. The mechanistic proposal has been rationalised against the reaction of a range of 13C- and deuterium-labelled substrates.

  13. Galactic Observations of Terahertz C+ (GOT C+): [CII] Detection of Warm "Dark Gas" in the ISM

    Science.gov (United States)

    Langer, W. D.; Velusamy, T.; Pineda, J.; Goldsmith, P.; Li, D.; Yorke, H. W.

    2011-11-01

    The Herschel HIFI Key Program, Galactic Observations of Terahertz C+ (GOT C+) is a survey of [CII] 1.9 THz emission throughout the Galaxy. Comparison of the first results of this survey with HI and CO isotopomer emission reveals excess [CII] emission beyond that expected from HI and CO layers alone, and is best explained as coming from a hidden layer of H2 gas, the so-called ISM "dark gas".

  14. Simultaneous measurement of neuronal and glial metabolism in rat brain in vivo using co-infusion of [1,6- 13C 2]glucose and [1,2- 13C 2]acetate

    Science.gov (United States)

    Deelchand, Dinesh K.; Nelson, Christopher; Shestov, Alexander A.; Uğurbil, Kâmil; Henry, Pierre-Gilles

    2009-02-01

    In this work the feasibility of measuring neuronal-glial metabolism in rat brain in vivo using co-infusion of [1,6- 13C 2]glucose and [1,2- 13C 2]acetate was investigated. Time courses of 13C spectra were measured in vivo while infusing both 13C-labeled substrates simultaneously. Individual 13C isotopomers (singlets and multiplets observed in 13C spectra) were quantified automatically using LCModel. The distinct 13C spectral pattern observed in glutamate and glutamine directly reflected the fact that glucose was metabolized primarily in the neuronal compartment and acetate in the glial compartment. Time courses of concentration of singly and multiply-labeled isotopomers of glutamate and glutamine were obtained with a temporal resolution of 11 min. Although dynamic metabolic modeling of these 13C isotopomer data will require further work and is not reported here, we expect that these new data will allow more precise determination of metabolic rates as is currently possible when using either glucose or acetate as the sole 13C-labeled substrate.

  15. Measurements of the microwave spectrum, Re-H bond length, and Re quadrupole coupling for HRe(CO)5

    Science.gov (United States)

    Kukolich, Stephen G.; Sickafoose, Shane M.

    1993-11-01

    Rotational transition frequencies for rhenium pentacarbonyl hydride were measured in the 4-10 GHz range using a Flygare-Balle type microwave spectrometer. The rotational constants and Re nuclear quadrupole coupling constants for the four isotopomers, (1) H187Re(CO)5, (2) H185Re(CO)5, (3) D187Re(CO)5, and (4) D185Re(CO)5, were obtained from the spectra. For the most common isotopomer, B(1)=818.5464(2) MHz and eq Q(187Re)=-900.13(3) MHz. The Re-H bond length (r0) determined by fitting the rotational constants is 1.80(1) Å. Although the Re atom is located at a site of near-octahedral symmetry, the quadrupole coupling is large due to the large Re nuclear moments. A 2.7% increase in Re quadrupole coupling was observed for D-substituted isotopomers, giving a rather large isotope effect on the quadrupole coupling. The Cax-Re-Ceq angle is 96(1)°, when all Re-C-O angles are constrained to 180°.

  16. Department of Nuclear Radiospectroscopy - Overview

    International Nuclear Information System (INIS)

    Jasinski, A.

    2000-01-01

    Full text: Research at the Department of Nuclear Radiospectroscopy concerns various aspects of nuclear magnetic resonance (NMR) and its applications to solids and to biosystems. Current research activity covers two areas: investigation of molecular dynamics and structures in solids using magnetic resonance spectroscopy, and investigation of humans, small animals and plants using magnetic resonance imaging and localized spectroscopy. MAGNETIC RESONANCE LABORATORY: Molecular reorientation studies aimed at disclosing tunnelling rotation and structural research of amorphous solids were our main topics. Realisation of these projects, both supported by the grants of the State Scientific Committee, required a continuous development of our NMR pulse spectrometer and theoretical methods. Partially deuterated ammonium ions open a new field in studies of molecular mobility and crystal structure. We may point out new features observed in 2 H-NMR spectra of ammonium ion isotopomers NH 4-x D x + . Following observations and conclusions are based on recent experiments: - evidence for tunneling rotation of ND 2 H 2 + and ND 3 H + ions, - evidence for the domain structure in the ordered phase and high mobility of ammonium ions in domain walls. The application of high resolution solid state NMR spectroscopy to the studies of novel heterogeneous catalysts was continued in 1999. The static and MAS-NMR spectra of 51 V deposited on various substrates were measured. It was possible to determine the coordination, local symmetry and the type of association of vanadium complexes, and correlate this structural information with the catalytic activity and selectivity in model reactions. The short range structure and the nature of local inhomogeneities in the multicomponent polymeric oxide glasses were studied using the high resolution MAS-NMR technique. MAS-NMR spectra of 29 Si, 31 P, 11 B, and 27 AI were measured for two model glasses. The MAS-NMR has been found to be the only technique that

  17. Retrobiosynthetic NMR studies with 13C-labeled glucose. Formation of gallic acid in plants and fungi

    International Nuclear Information System (INIS)

    Werner, I.; Bacher, A.; Eisenreich, W.

    1997-01-01

    The biosynthesis of gallic acid was studied in cultures of the fungus Phycomyces blakesleeanus and in leaves of the tree Rhus typhina. Fungal cultures were grown with [1-13C]glucose or with a mixture of unlabeled glucose and [U-13C6]glucose. Young leaves of R. typhina were kept in an incubation chamber and were supplied with a solution containing a mixture of unlabeled glucose and [U-13C6]glucose via the leaf stem. Isotope distributions in isolated gallic acid and aromatic amino acids were analyzed by one-dimensional 1H and 13C NMR spectroscopy. A quantitative analysis of the complex isotopomer composition of metabolites was obtained by deconvolution of the 13C13C coupling multiplets using numerical simulation methods. This approach required the accurate analysis of heavy isotope chemical shift effects in a variety of different isotopomers and the analysis of long range 13C13C coupling constants. The resulting isotopomer patterns were interpreted using a retrobiosynthetic approach based on a comparison between the isotopomer patterns of gallic acid and tyrosine. The data show that both in the fungus and in the plant all carbon atoms of gallic acid are biosynthetically equivalent to carbon atoms of shikimate. Notably, the carboxylic group of gallic acid is derived from the carboxylic group of an early intermediate of the shikimate pathway and not from the side chain of phenylalanine or tyrosine. It follows that the committed precursor of gallic acid is an intermediate of the shikimate pathway prior to prephenate or arogenate, most probably 5-dehydroshikimate. A formation of gallic acid via phenylalanine, the lignin precursor, caffeic acid, or 3,4, 5-trihydroxycinnamic acid can be ruled out as major pathways in the fungus and in young leaves of R. typhina. The incorporation of uniformly 13C-labeled glucose followed by quantitative NMR analysis of isotopomer patterns is suggested as a general method for biosynthetic studies. As shown by the plant experiment, this

  18. High-resolution studies of tropolone in the S0 and S1 electronic states: isotope driven dynamics in the zero-point energy levels.

    Science.gov (United States)

    Keske, John C; Lin, Wei; Pringle, Wallace C; Novick, Stewart E; Blake, Thomas A; Plusquellic, David F

    2006-02-21

    Rotationally resolved microwave (MW) and ultraviolet (UV) spectra of jet-cooled tropolone have been obtained in S(0) and S(1) electronic states using Fourier-transform microwave and UV-laser/molecular-beam spectrometers. In the ground electronic state, the MW spectra of all heavy-atom isotopomers including one (18)O and four (13)C isotopomers were observed in natural abundance. The OD isotopomer was obtained from isotopically enriched samples. The two lowest tunneling states of each isotopomer except (18)O have been assigned. The observed inversion splitting for the OD isotopomer is 1523.227(5) MHz. For the asymmetric (13)C structures, the magnitudes of tunneling-rotation interactions are found to diminish with decreasing distance between the heavy atom and the tunneling proton. In the limit of closest approach, the 0(+) state of (18)O was well fitted to an asymmetric rotor Hamiltonian, reflecting significant changes in the tautomerization dynamics. Comparisons of the substituted atom coordinates with theoretical predictions at the MP2/aug-cc-pVTZ level of theory suggest the localized 0(+) and 0(-) wave functions of the heavier isotopes favor the C-OH and C=O forms of tropolone, respectively. The only exception occurs for the (13)C-OH and (13)C[Double Bond]O structures which correlate to the 0(-) and 0(+) states, respectively. These preferences reflect kinetic isotope effects as quantitatively verified by the calculated zero-point energy differences between members of the asymmetric atom pairs. From rotationally resolved data of the 0(+) <--0(+) and 0(-) <--0(-) bands in S(1), line-shape fits have yielded Lorentzian linewidths that differ by 12.2(16) MHz over the 19.88(4) cm(-1) interval in S(1). The fluorescence decay rates together with previously reported quantum yield data give nonradiative decay rates of 7.7(5) x 10(8) and 8.5(5) x 10(8) s(-1) for the 0(+) and 0(-) levels of the S(1) state of tropolone.

  19. Enhanced photosynthetic efficiency in trees world-wide by rising atmospheric CO2 levels

    Science.gov (United States)

    Ehlers, Ina; Wieloch, Thomas; Groenendijk, Peter; Vlam, Mart; van der Sleen, Peter; Zuidema, Pieter A.; Robertson, Iain; Schleucher, Jürgen

    2014-05-01

    The atmospheric CO2 concentration is increasing rapidly due to anthropogenic emissions but the effect on the Earth's biosphere is poorly understood. The ability of the biosphere to fix CO2 through photosynthesis will determine future atmospheric CO2 concentrations as well as future productivity of crops and forests. Manipulative CO2 enrichment experiments (e.g. FACE) are limited to (i) short time spans, (ii) few locations and (iii) large step increases in [CO2]. Here, we apply new stable isotope methodology to tree-ring archives, to study the effect of increasing CO2 concentrations retrospectively during the past centuries. We cover the whole [CO2] increase since industrialization, and sample trees with global distribution. Instead of isotope ratios of whole molecules, we use intramolecular isotope distributions, a new tool for tree-ring analysis with decisive advantages. In experiments on annual plants, we have found that the intramolecular distribution of deuterium (equivalent to ratios of isotopomer abundances) in photosynthetic glucose depends on growth [CO2] and reflects the metabolic flux ratio of photosynthesis to photorespiration. By applying this isotopomer methodology to trees from Oak Ridge FACE experiment, we show that this CO2 response is present in trees on the leaf level. This CO2 dependence constitutes a physiological signal, which is transferred to the wood of the tree rings. In trees from 13 locations on all continents the isotopomer ratio of tree-ring cellulose is correlated to atmospheric [CO2] during the past 200 years. The shift of the isotopomer ratio is universal for all 12 species analyzed, including both broad-leafed trees and conifers. Because the trees originate from sites with widely differing D/H ratios of precipitation, the generality of the response demonstrates that the signal is independent of the source isotope ratio, because it is encoded in an isotopomer abundance ratio. This decoupling of climate signals and physiological

  20. Characteristics of micro transfer paths and diffusion phenomena in the matrix of deep crystalline rock

    International Nuclear Information System (INIS)

    Ishibashi, Masayuki; Sasao, Eiji; Hama, Katsuhiro

    2016-01-01

    Matrix diffusion is one of the important phenomena for evaluating the safety of the geological disposal of high level waste because it has an effect of retarding mass transport in crystalline rocks. Previous studies indicated that the altered granitic rocks have high retardation functions due to the micropore formation associated with hydrothermal alteration; however, there has not been enough knowledge on the matrix diffusion in weakly unaltered rocks (macroscopically unaltered rocks). Since the macroscopically altered granitic rocks in Japan are likely to be affected by deuteric alteration due to hydrothermal flu resulting from crystallization of granitic magma, it is important to understand the effect of deuteric alteration on the matrix diffusion. Therefore, detailed observations were carried out to clarify the effects of deuteric alteration focused on the macroscopically unaltered granite sampled from 300 m and 500 m below ground levels at the Mizunami Underground Research Laboratory, central Japan. The results provide that the micropores are selectively formed in plagioclases due to deuteric alteration and they have the potential of acting as matrix diffusion paths. This is indicating the possibility that deuteric alteration can retard the mass transport in crystalline rocks in Japan. That plays a significant role in enforcing the barrier function of crystalline rocks. (author)

  1. H{sub 2} Ortho-to-para Conversion on Grains: A Route to Fast Deuterium Fractionation in Dense Cloud Cores?

    Energy Technology Data Exchange (ETDEWEB)

    Bovino, S. [Hamburger Sternwarte, Universität Hamburg, Gojenbergsweg 112, D-21029 Hamburg (Germany); Grassi, T. [Centre for Star and Planet Formation, Niels Bohr Institute and Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5-7, DK-1350 Copenhagen (Denmark); Schleicher, D. R. G. [Departamento de Astronomía, Facultad Ciencias Físicas y Matemáticas, Universidad de Concepción, Av. Esteban Iturra s/n Barrio Universitario, Casilla 160, Concepción (Chile); Caselli, P., E-mail: stefano.bovino@uni-hamburg.de [Max-Planck-Institut für extraterrestrische Physik, Giessenbachstrasse 1, D-85748 Garching (Germany)

    2017-11-10

    Deuterium fractionation, i.e., the enhancement of deuterated species with respect to non-deuterated ones, is considered to be a reliable chemical clock of star-forming regions. This process is strongly affected by the ortho-to-para H{sub 2} ratio. In this Letter we explore the effect of the ortho–para (o–p) H{sub 2} conversion on grains on the deuteration timescale in fully-depleted dense cores, including the most relevant uncertainties that affect this complex process. We show that (i) the o–p H{sub 2} conversion on grains is not strongly influenced by the uncertainties on the conversion time and the sticking coefficient, and (ii) that the process is controlled by the temperature and the residence time of ortho-H{sub 2} on the surface, i.e., by the binding energy. We find that for binding energies between 330 and 550 K, depending on the temperature, the o–p H{sub 2} conversion on grains can shorten the deuterium fractionation timescale by orders of magnitude, opening a new route for explaining the large observed deuteration fraction D {sub frac} in dense molecular cloud cores. Our results suggest that the star formation timescale, when estimated through the timescale to reach the observed deuteration fractions, might be shorter than previously proposed. However, more accurate measurements of the binding energy are needed in order to better assess the overall role of this process.

  2. Phenomenological nuclear reaction description in deuterium-saturated palladium and synthesized structure in dense deuterium gas under γ-quanta irradiation

    International Nuclear Information System (INIS)

    Didyk, A.Yu.; Wisniewski, R.

    2012-01-01

    The observed phenomena on the changes of chemical compositions in our previous reports allowed us to develop a phenomenological nuclear fusion-fission model with taking into consideration the elastic and inelastic scattering of photoprotons and photoneutrons, heating of surrounding deuterium nuclei, following D-D fusion reactions and fission of middle-mass nuclei by 'hot' protons, deuterons and various-energy neutrons. Such chain processes could produce the necessary number of neutrons, 'hot' deuterons for explanation of the observed experimental results. The developed approach can be a basis for creation of deuterated nuclear fission reactors (DNFR) with high-density deuterium gas and so-called deuterated metals. Also, the developed approach can be used for the study of nuclear reactions in high-density deuterium or tritium gases and deuterated metals

  3. Investigation on cold fusion phenomena using gas-metal loading experiments

    International Nuclear Information System (INIS)

    Lanza, F.; Bertolini, G.; Vocino, V.; Parnisari, E.; Ronsecco, C.

    1992-01-01

    Previous experiments have shown that tritium is produced in deuterated titanium. The data obtained are highly scattered and non reproducible. In order to try to define better the phenomenon a series of tests have been performed using various metals and alloys and different deuterating conditions. Sheets and shavings of titanium, zirconium, hafnium, tantalum, zircaloy 2 and Ti-Zr 5O% alloy have been tested. The tritium production is obtained as a difference of the tritium content in the deuterated metal and the initial content of tritium in the deuterium gas. The amount of tritium produced is low and reproducibility is rather poor. A statistical analysis shows that significant differences are obtained varying the type of metal used. In general the tritium production increases with the atomic number of the metal. Moreover significantly higher productions of tritium have been obtained using materials of technical purity as tantalum, zircaloy 2 and Ti-Zr alloy

  4. Site occupation state of deuterium atoms in fcc Fe

    International Nuclear Information System (INIS)

    Aoki, Katsutoshi; Machida, Akihiko; Saitoh, Hiroyuki; Hattori, Takanori; Sano-Furukawa, Asami

    2015-01-01

    The deuterization process of fcc Fe to form solid-solution fcc FeD x was investigated by in situ neutron diffraction measurements at high temperature and high pressure. In a completely deuterized specimen at 988 K and 6.3 GPa, deuterium atoms occupy the octahedral and tetrahedral interstitial sites with an occupancy of 0.532(9) and 0.056(5), respectively, giving a deuterium composition x of 0.64(1). During deuterization, the metal-lattice expands approximately linearly with deuterium composition at a rate of 2.21 Å 3 per deuterium atom. The minor occupation of tetrahedral site is likely driven by the intersite movement of deuterium atoms along the <111> direction in the fcc metal lattice. These results provide implications for the light elements in the Earth's core and the mechanism of hydrogen embrittlement of ferrous metals. (author)

  5. The performance studies of DKDP crystals grown by a rapid horizontal growth method

    Science.gov (United States)

    Xie, Xiaoyi; Qi, Hongji; Wang, Bin; Wang, Hu; Chen, Duanyang; Shao, Jianda

    2018-04-01

    A deuterated potassium dihydrogen phosphate (DKDP) crystal with about 70% deuterium level was grown by a rapid horizontal growth method with independent design equipment, which includes a continuous filtration system. The cooling program during crystal growth was designed according to a self-developed software to catch the size of growing crystal in real time. The crystal structure, optical performance and laser induced damage threshold (LIDT) of this DKDP crystal were investigated in this paper. The deuterium concentration of the crystal was confirmed by the neutron diffraction technique, which was effective and available in determining a complete range of deuteration level. The dielectric property was measured to evaluate the perfection of the lattice. The transmittance and LIDT were carried out further to evaluate the optical and functional properties of this DKDP crystal grown in the rapid horizontal growth technique. All of the detailed characterization for DKDP figured out that the 70% deuterated KDP crystal grown in this way had relatively good qualities.

  6. Neutron Scattering of Residual Hydrogen in 1,4-Dioxane-D8 Liquid. Understanding Measurements with Molecular Dynamics Simulations

    Energy Technology Data Exchange (ETDEWEB)

    de Almeida, Valmor F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liu, Hongjun [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Herwig, Kenneth W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kidder, Michelle [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-01-25

    That incoherent scattering from protiated molecular liquids adds a constant background to the measured scattering intensity is well known, but less appreciated is the fact that coherent scattering is also induced by the presence of hydrogen in a deuterated liquid. In fact, the scattering intensity can be very sensitive, in the small-q region, with respect to the amounts and distribution of residual H in the system. We used 1,4-dioxane liquid to demonstrate that the partial structure factors of the HD and DD atom pairs contribute significantly to inter-molecular scattering and that uncertainty in the extent of deuteration account for discrepancies between simulations and measurements. Both contributions to uncertainty have similar magnitudes: scattering interference of the hydrogen-deuterium pair, and complementary interference from the deuterium-deuterium pair by virtue of chemical inhomogeneity. This situation arises in practice since deuteration of liquids is often 99% or less. A combined experimental and extensive computational study of static thermal neutron scattering of 1,4-dioxane demonstrates the foregoing. We show, through simulations, that the reason for the differences is the content of protiated dioxane (vendors quote 1%). We estimate that up to 5% (at 298K and at 343K) protiated mole fraction may be involved in generating the scattering differences. Finally, we find that the particular distribution of hydrogen in the protiated molecules affects the results significantly; here we considered molecules to be either fully protiated or fully deuterated. This scenario best reconciles the computational and experimental results, and leads us to speculate that the deuteration synthesis process tends to leave a molecule either fully deuterated or fully protiated. Although we have used 1,4-dioxane as a model liquid, the effects described in this study extend to similar liquids and similar systematic experimental/computational studies can be performed to either

  7. Process for the production of high purity deuterium

    International Nuclear Information System (INIS)

    Arrathoon, R.

    1977-01-01

    A process for the electrolysis of heavy water which results in the production of high purity deuterium without periodic replenishment of the electrolyte with additional deuterated compounds is defined. Electrolysis is effected through the use of an inexpensive cation-action permselective membrane which is essentially a solid polymer electrolyte and which is capable of automatically separating the evolved deuterium and oxygen gas. This cation-active permselective membrane does not introduce any intrinsic impurities or tritium contamination in the generated deuterium gas, does not require periodic revitalization with deuterated compounds or other chemical compounds, and is characterized by an unusually high electrical efficiency

  8. Target Monitoring and Plasma Diagnosis using 2ω probe beam for CANDY

    International Nuclear Information System (INIS)

    Ishii, Katsuhiro; Mori, Yoshitaka; Hanayama, Ryohei; Nakayama, Suisei; Okihara, Shinichiro; Fujita, Kazuhisa; Nishimura, Yasuhiko; Sekina, Takashi; Sato, Nakahiro; Kurita, Takashi; Kawashima, Toshiyuki; Kan, Hirofumi; Komeda, Osamu; Nakamura, Naoki; Kondo, Takuya; Fujine, Manabu; Azuma, Hirozumi; Hioki, Tatsumi; Kakeno, Mitsutaka; Motohiro, Tomoyoshi

    2016-01-01

    We have developed the shadowgraph and interferometer with second-harmonic of heating pulses laser to observe target and plasma in highly-repetitive fusion reaction experiments. In the deuterated polystyrene ((C 8 D 8 )n double foil experiment, we confirm implosion plasma and plasma collision. In target injection experiment at a 1 Hz rate, we measure the position of the flying deuterated polystyrene beads at the moment of laser pulse illumination and observe the plasma generation by counter-illumination by 0.63 J, 800 nm, and 104 fs laser pulses. (paper)

  9. Characterization of the transverse relaxation rates in lipid bilayers

    International Nuclear Information System (INIS)

    Watnick, P.I.; Dea, P.; Chan, S.I.

    1990-01-01

    The 2H NMR transverse relaxation rates of a deuterated phospholipid bilayer reflect slow motions in the bilayer membrane. A study of dimyristoyl lecithin specifically deuterated at several positions of the hydrocarbon chains indicates that these motions are cooperative and are confined to the hydrocarbon chains of the lipid bilayer. However, lipid head group interactions do play an important role in modulating the properties of the cooperative fluctuations of the hydrocarbon chains (director fluctuations), as evidenced by the effects of various lipid additives on the 2H NMR transverse relaxation rates of the dimyristoyl lecithin bilayer

  10. Deuteron NMR (Nuclear Magnetic Resonance) in relation to the glass transition in polymers

    Science.gov (United States)

    Roessler, E.; Sillescu, H.; Spiess, H. W.; Wallwitz, R.

    1983-01-01

    H-2NMR is introduced as a tool for investigating slow molecular motion in the glass transition region of amorphous polymers. In particular, we compare H-2 spin alignment echo spectra of chain deuterated polystyrene with model calculations for restricted rotational Brownian motion. Molecular motion in the polyztyrene-toluene system has been investigated by analyzing H-2NMR of partially deuterated polystyrene and toluene, respectively. The diluent mobility in the mixed glass has been decomposed into solid and liquid components where the respective average correlation times differ by more than 5 decades.

  11. Compression of glycolide-h4 to 6GPa

    DEFF Research Database (Denmark)

    Hutchison, Ian B.; Bull, Craig L.; Marshall, William G.

    2017-01-01

    This study details the structural characterization of glycolide-h4 as a function of pressure to 6GPa using neutron powder diffraction on the PEARL instrument at ISIS Neutron and Muon source. Glycolide-h4, rather than its deuterated isotopologue, was used in this study due to the difficulty...... of deuteration. The low background afforded by zirconia-toughened alumina anvils nevertheless enabled the collection of data suitable for structural analysis to be obtained to a pressure of 5GPa. Glycolide-h4 undergoes a reconstructive phase transition at 0.15GPa to a previously identified form (II), which...

  12. Comparative study of heavy and deuterium-depleted water on platelet aggregation

    International Nuclear Information System (INIS)

    Haulica, I.; Neagu, B.; Boisteanu, C.P.; Bild, W.; Mihaila, C.; Bajenariu, M.

    2000-01-01

    The effects of timed incubation of PRP (Platelet-Rich Plasma) with various concentrations of deuterium-depleted or deuterated water were tested. Aggregation curves were obtained under constant stirring at 20 deg.C and at 37 deg.C, using 5 - 10 μM ADP as aggregation trigger, using a Specord photo colorimeter. Incubation with 10 % deuterated water showed a significant decrease in the aggregation curves, an effect consistent with the data in the literature. Incubation with deuterium depleted water in the same conditions showed a marked increase in the aggregation curves, which suggests a powerful pro-aggregating effect of deuterium depleted water. (authors)

  13. Small angle neutron scattering study of the micelle structure of amphiphilic block copolymers

    International Nuclear Information System (INIS)

    Yamaoka, H.; Matsuoka, H.; Sumaru, K.; Hanada, S.

    1994-01-01

    The amphiphilic block copolymers of vinyl ether were prepared by living cationic polymerization. The partially deuterated copolymers for SANS experiments were especially synthesized by introducing deuterated phenyl units in the hydrophobic chain. SANS measurements were performed for aqueous solutions of these copolymers by changing H 2 O/D 2 O ratios. The SANS profiles indicate that the micelles in the present system exhibit a core-shell structure and that the size and shape of micelles are largely dependent on the length of hydrophobic chain. The micelle of shorter hydrophobic chain was found to be nearly spherical, whereas the micelle of longer hydrophobic chain was confirmed to have an ellipsoidal shape

  14. In situ and real-time small-angle neutron scattering studies of living anionic polymerization process and polymerization-induced self-assembly of block copolymers

    International Nuclear Information System (INIS)

    Tanaka, H.; Yamauchi, K.; Hasegawa, H.; Miyamoto, N.; Koizumi, S.; Hashimoto, T.

    2006-01-01

    We have studied a simultaneous living anionic polymerization process of isoprene and deuterated styrene in deuterated benzene with sec-buthyl lithium as an initiator into polyisoprene-block-poly(styrene-d 8 ) and the polymerization-induced self-assembling process. This polymerization-induced self-assembling process was directly observed by an in situ and real-time small-angle neutron scattering (SANS) experiment. The time-resolved SANS studies enabled us to explore a time evolution of hierarchical structures induced by a time evolution of the primary structure (linear sequential connection of two monomers)

  15. Preparation of folic acid specifically labeled with deuterium at the 3',5'-positions

    International Nuclear Information System (INIS)

    Gregory, J.F. III; Toth, J.P.

    1988-01-01

    A method was devised for the synthesis of 3', 5'-[ 2 H 2 ]folic acid (d 2 -folic acid) for use in studies of folate metabolism in human beings. Labeling was accomplished by catalytic dehalogenation of 3', 5'-dibromofolate with deuterium gas and palladium/carbon catalyst. d 2 -Folic acid was separated from reduced forms and residual 3'-monobromofolate by chromatography on DEAE-Sephadex. Analysis by proton NMR and mass spectrometry indicated 70-75% deuteration of the 3',5'-positions and lack of deuteration at other carbons. (author)

  16. Spatially resolved protein hydrogen exchange measured by subzero-cooled chip-based nanoelectrospray ionization tandem mass spectrometry

    DEFF Research Database (Denmark)

    Amon, Sabine; Trelle, Morten B; Jensen, Ole N

    2012-01-01

    . After a given period of deuteration, the exchange reaction is quenched by acidification (pH 2.5) and cooling (0 °C) and the deuterated protein (or a digest thereof) is analyzed by mass spectrometry. The unavoidable loss of deuterium (back-exchange) that occurs under quench conditions is undesired...... as it leads to loss of information. Here we describe the successful application of a chip-based nanoelectrospray ionization mass spectrometry top-down fragmentation approach based on cooling to subzero temperature (-15 °C) which reduces the back-exchange at quench conditions to very low levels. For example...

  17. Application of solid-state tritium NMR in determining the bioactive conformation of paclitaxel

    International Nuclear Information System (INIS)

    Lin, T.

    2012-01-01

    The determination of the conformation of small molecule bound to its biological target would facilitate people to design improved drugs. This determination can be difficult due to technical limitations, as exemplified by the long standing debate on the microtubule-binding conformation of a natural anticancer drug - paclitaxel. Previous studies using X-ray crystallography and solution-state NMR failed to furnish direct information on the expected conformation. Solid-state NMR may help in this task by providing precise interatomic distances, and the selective labeling on different sites with tritium atoms enables accurate measurement of long-range distances (up to 14.4 Angstroms) owing to the high gyromagnetic ratio of this nucleus, without any structural modification of the molecule. So our project aiming at illustrating the bioactive conformation of paclitaxel consists the syntheses of 6 different paclitaxel isotopomers bearing a pair of tritium at specified positions, flowing by the preparations of corresponding microtubule-labeled paclitaxel complexes. The solid-state tritium NMR analyses of these complexes would provide key distances for determining the expected conformation. Up to now, 2 paclitaxel isotopomers have been prepared from labelling the di-brominated paclitaxel precursor and from coupling the tritiated taxane rings and the tritiated side chains, respectively. The synthetic strategy allowed us to realize the syntheses in generally high yield and good stereoselectivity. Different tritiation methods have been used, from which an isotopic enrichment of higher than 92% was obtained. The syntheses of other 4 isotopomers, together with the microtubule complexes are currently underway in our lab. (author) [fr

  18. Wave-packet dynamics in alkaline dimers. Investigation and control through coherent excitation with fs-pulses

    International Nuclear Information System (INIS)

    Sauer, F.N.B.

    2007-01-01

    During my PhD thesis I investigated alkaline dimers with coherent control in a molecular beam as well as with pump-probe spectroscopy in a magneto-optical trap (MOT). The aim of the coherent control experiments were the isotope selective ionization with phase- and amplitude-shaped fs-pulses. Chapter 4 described the gained results of isotope selective ionization of NaK and KRb in a molecular beam by using different pulse formers. For the NaK dimer was the reached optimization factor R Ph and Ampl 770 =R max /R min =25 between maximization and minimization of the isotopomer ratio ( 23 Na 39 K) + /( 23 Na 41 K) + with phase and amplitude modulation of the fs-pulse with a central wavelength of λ=770 nm. From the electronic ground-state X(1) 1 Σ + ;ν''=0 transfers a one-photon-excitation population in the first excited A(2) 1 Σ + state. The coherent control experiment on KRb was used to maximize and minimize the isotopomer ratio ( 124 KRb) + /( 126 KRb) + . It was the first coherent control experiment with a spectral resolution of 1.84 cm -1 /Pixel. For the phase and amplitude optimization was the received optimization factor between minimization and maximization of the isotopomer ratio R Ph and Ampl =R max /R min =7 at a central wavelength of 840 nm. The results showed a stepwise excitation process from the electronic ground-state in the first excited (2) 1 Σ + state with a further excitation, that is possible over three resonant energy potential curves into the ionic ground-state. In the second part of my thesis I realized pump-probe spectroscopy of Rb 2 dimers in a dark SPOT. (orig.)

  19. Molecular dynamics simulation based on the multi-component molecular orbital method: Application to H5O2+,D5O2+,andT5O2+

    International Nuclear Information System (INIS)

    Ishimoto, Takayoshi; Koyama, Michihisa

    2012-01-01

    Graphical abstract: Molecular dynamics method based on multi-component molecular orbital method was applied to basic hydrogen bonding systems, H 5 O 2 + , and its isotopomers (D 5 O 2 + andT 5 O 2 + ). Highlights: ► Molecular dynamics method with nuclear quantum effect was developed. ► Multi-component molecular orbital method was used as ab initio MO calculation. ► Developed method applied to basic hydrogen bonding system, H 5 O 2 + , and isotopomers. ► O ⋯ O vibrational stretching reflected to the distribution of protonic wavefunctions. ► H/D/T isotope effect was also analyzed. - Abstract: We propose a molecular dynamics (MD) method based on the multi-component molecular orbital (MC M O) method, which takes into account the quantum effect of proton directly, for the detailed analyses of proton transfer in hydrogen bonding system. The MC M O based MD (MC M O-MD) method is applied to the basic structures, H 5 O 2 + (called “Zundel ion”), and its isotopomers (D 5 O 2 + andT 5 O 2 + ). We clearly demonstrate the geometrical difference of hydrogen bonded O ⋯ O distance induced by H/D/T isotope effect because the O ⋯ O in H-compound was longer than that in D- or T-compound. We also find the strong relation between stretching vibration of O ⋯ O and the distribution of hydrogen bonded protonic wavefunction because the protonic wavefunction tends to delocalize when the O ⋯ O distance becomes short during the dynamics. Our proposed MC M O-MD simulation is expected as a powerful tool to analyze the proton dynamics in hydrogen bonding systems.

  20. Communication: The highest frequency hydrogen bond vibration and an experimental value for the dissociation energy of formic acid dimer

    DEFF Research Database (Denmark)

    Kollipost, F.; Larsen, René Wugt; Domanskaya, A.V.

    2012-01-01

    The highest frequency hydrogen bond fundamental of formic acid dimer, ν24 (Bu), is experimentally located at 264 cm−1. FTIR spectra of this in-plane bending mode of (HCOOH)2 and band centers of its symmetric D isotopologues (isotopomers) recorded in a supersonic slit jet expansion are presented...... thermodynamics treatment of the dimerization process up to room temperature. We obtain D0 = 59.5(5) kJ/mol as the best experimental estimate for the dimer dissociation energy at 0 K. Further improvements have to wait for a more consistent determination of the room temperature equilibrium constant....

  1. The vibrational spectra of some tetrachlorides in rare gas matrices with particular reference to the molecular shapes of ThCl4 and UCl4

    International Nuclear Information System (INIS)

    Arthers, S.A.; Beattie, I.R.

    1984-01-01

    Infrared spectra of tin, lead, hafnium, thorium, and uranium tetrachlorides isolated in inert gas matrices are reported. The results obtained for the tin, lead, and hafnium compounds follow the expected isotope patterns for a tetrahedral molecule except for the observation of additional weak features to high frequency of the all- 35 Cl isotopomers. By contrast for thorium tetrachloride the observed spectrum is not characteristic of a Tsub(d) molecule but can be fitted to a species with Csub(2v) symmetry. Similar results (although less detailed) were obtained for uranium tetrachloride. (author)

  2. The Fourier Transform Microwave (ftmw) Spectra of Cyclohexene Oxide and its Argon Complex

    Science.gov (United States)

    Frohman, Daniel J.; Novick, Stewart E.; Pringle, Wallace C.

    2012-06-01

    The microwave spectrum of cyclohexene oxide and its isotopologues have been observed and assigned, improving upon previous rotational studies of this molecule. Additionally, the 17O isotopomer of cyclohexene oxide and the Ar complex of the normal isotopologue of cyclohexene oxide have been fit for the first time. Fits for the 13C-cyclohexene oxide Ar complexes will also be presented. Tatsuya Ikeda, Roger Kewley, and R. F. Curl, Jr. J. Mol. Spectrosc., 4} (1972), 459-469. Raquel Sánchez, Susana Blanco, Juan C. López, and José L. Alonso. J. Mol. Struct., 780-781 (2006), 57-64.

  3. [Changes of chlorine isotope composition characterize bacterial dehalogenation of dichloromethane].

    Science.gov (United States)

    Ziakun, A M; Firsova, Iu E; Torgonskaia, M L; Doronina, N V; Trotsenko, Iu A

    2007-01-01

    Fractionation of dichloromethane (DCM) molecules with different chlorine isotopes by aerobic methylobacteria Methylobacterium dichloromethanicum DM4 and Albibacter nethylovorans DM10; cell-free extract of strain DM4; and transconjugant Methylobacterium evtorquens Al1/pME 8220, expressing the dcmA gene for DCM dehalogenase but unable to grow on DCM, was studied. Kinetic indices of DCM isotopomers for chlorine during bacterial dehalogenation and diffusion were compared. A two-step model is proposed, which suggests diffusional DCM transport to bacterial cells.

  4. Einstein A-coefficients and statistical weights for molecular absorption transitions in the HITRAN database

    International Nuclear Information System (INIS)

    Simeckova, Marie; Jacquemart, David; Rothman, Laurence S.; Gamache, Robert R.; Goldman, Aaron

    2006-01-01

    This paper describes the calculation of the statistical weights and the Einstein A-coefficients for the 39 molecules and their associated isotopologues/isotopomers currently present in the line-by-line portion of the HITRAN database. Calculation of the Einstein A-coefficients was carried out using the HITRAN line intensities and the necessary statistical weights. The Einstein A-coefficient and the statistical weights of the upper and lower levels of the transition were added in the new format of the line parameters for the most recent edition of the HITRAN database

  5. Synthesis of carrier-free tritium-labeled queen bee pheromone

    International Nuclear Information System (INIS)

    Webster, F.X.; Prestwich, G.D.

    1988-01-01

    A short synthesis of [4,5- 3 H 2 ] (E)-9-oxo-2-decenoic acid (ODA), a high-specific-activity tritium-containing isotopomer of the queen bee pheromone, is described. Catalytic tritiation of the ketal of ethyl 9-oxo-4-decenoate introduces tritium into two positions, one of which is completely unactivated. Subsequent transformation by selenation, oxidation, and hydrolysis affords the labeled 9-ODA at >60 Ci/mmol. The material is suitable for biochemical studies of binding and catabolism in ovarian, antennal, and other target tissues

  6. Full-dimensional characterization of photoelectron spectra of HOCO− and DOCO− and tunneling facilitated decay of HOCO prepared by anion photodetachment

    International Nuclear Information System (INIS)

    Wang, Jun; Li, Jun; Guo, Hua; Ma, Jianyi

    2014-01-01

    The photodetachment of both the HOCO − and DOCO − anions is investigated using full-dimensional quantum wave packets on new ab initio based global potential energy surfaces for both the neutral and anionic species. The calculated electron affinities and neutral fundamental vibrational frequencies of both isotopomers are in good agreement with available experimental data. The measured photoelectron spectra are also accurately reproduced, further validating the accuracy of the potential energy surfaces. In addition, strong mode specificity is found in the lifetimes of the HOCO vibrational features and the tunneling facilitated predissociation rates to H + CO 2 are rationalized using the recently proposed sudden vector projection model

  7. Far-infrared spectra of acetanilide revisited

    Science.gov (United States)

    Spire, A.; Barthes, M.; Kellouai, H.; De Nunzio, G.

    2000-03-01

    A new investigation of the temperature dependence of the far-infrared spectra of acetanilide and some isotopomers is presented. Four absorption bands are considered at 31, 42, 64, and 80 cm-1, and no significant change of their integrated intensity is observed when reducing the temperature. The temperature induced frequency shift values and other properties of these bands are consistent with an assignment as anharmonic lattice phonons. These results rule out the assignment of the 64, 80, and 106 cm-1 bands as normal modes of the polaronic excitation, as previously suggested.

  8. The antidiabetic drug metformin decreases mitochondrial respiration and tricarboxylic acid cycle activity in cultured primary rat astrocytes

    DEFF Research Database (Denmark)

    Hohnholt, Michaela C; Blumrich, Eva-Maria; Waagepetersen, Helle S

    2017-01-01

    , and malate, as well as the MCL of the TCA cycle intermediate-derived amino acids glutamate, glutamine, and aspartate. In addition to the total molecular 13 C labeling, analysis of the individual isotopomers of TCA cycle intermediates confirmed a severe decline in labeling and a significant lowering in TCA...... tricarboxylic acid (TCA) cycle metabolism in astrocytes are unknown. We investigated this by mapping 13 C labeling in TCA cycle intermediates and corresponding amino acids after incubation of primary rat astrocytes with [U-13 C]glucose. The presence of metformin did not compromise the viability of cultured...

  9. Hyperfine-resolved transition frequency list of fundamental vibration bands of H35Cl and H37Cl

    Science.gov (United States)

    Iwakuni, Kana; Sera, Hideyuki; Abe, Masashi; Sasada, Hiroyuki

    2014-12-01

    Sub-Doppler resolution spectroscopy of the fundamental vibration bands of H35Cl and H37Cl has been carried out from 87.1 to 89.9 THz. We have determined the absolute transition frequencies of the hyperfine-resolved R(0) to R(4) transitions with a typical uncertainty of 10 kHz. We have also yielded six molecular constants for each isotopomer in the vibrational excited state, which reproduce the determined frequencies with a standard deviation of about 10 kHz.

  10. Isotopologue signatures of nitrous oxide produced by nitrate-ammonifying bacteria isolated from soil

    Science.gov (United States)

    Behrendt, Undine; Well, Reinhard; Giesemann, Anette; Ulrich, Andreas; Augustin, Jürgen

    2015-04-01

    Agricultural soils are the largest single source of anthropogenic N2O to the atmosphere, primarily driven by microbiological processes such as denitrification and dissimilatory nitrate reduction to ammonium (DNRA). Both processes occur under similar conditions of low oxygen concentration and therefore, source partitioning of emitted N2O is difficult. Understanding what controls the dynamics and reaction equilibrium of denitrification and DNRA is important and may allow the development of more effective mitigation strategies. 15N site preference (SP), i.e. the difference between 15N of the central and peripheral N-position of the asymmetric N2O molecule, differs depending on processes involved in N2O formation. Hence investigation of the isotopomer ratios of formed N2O potentially presents a reliable mean to identify its source. In this study, bacterial isolates obtained from organic soils were screened for their ability to reduce nitrate/nitrite to ammonium and to release N2O to the atmosphere. Taxonomic characterisation of the strains revealed that N2O formation was only detected in ammonifying strains affiliated to several genera of the family Enterobacteriaceae and strains belonging to the genus Bacillus and Paenibacillus. Sampling of N2O was conducted by incubation of strains under oxic and anoxic conditions. Investigation of the 15N site preference showed SP values in the range of 39 to 57 o . Incubation conditions had no influence on the SP. The lowest values were achieved by a strain of the species Escherichia coli which was included in this study as a DNRA reference bacterium harbouring the NrfA gene that is coding the nitrite reductase, associated with respiratory nitrite ammonification. Soil isolates showed SP-values higher than 40 o . Comparison of these results with SP-values of N2O produced by denitrifying bacteria in pure cultures (-5 to 0 o )^[1, 2]revealedsignificantdifferences.Incontrast,N_2OproducedbydenitrifyingfungidisplayedSP - valuesinarangeof

  11. Synthesis of 1-[13CD3]-9-cis-retinoic acid

    International Nuclear Information System (INIS)

    Bennani, Y.L.

    1995-01-01

    1-[ 13 CD 3 ]-9-cis-Retinoic acid was prepared in 8 steps from 2,6-dimethylcyclohexanone. Alkylation of 2,6-dimethylcyclohexanone under LiHMDS/MnBr 2 / 13 CD 3 I gave the corresponding labeled 2-[ 13 CD 3 ]-2,2,6-trimethylcyclohexanone 4 in good yield. Further functionalization of 4 to 6-[ 13 CD 3 ]-β-cyclocitral 6 proceeded through a Shapiro reaction. Aldehyde 6 was condensed with ethyl 3,3-dimethylacrylate to afford the corresponding bicyclic pyranone 7. Reduction of 7 to lactol 8, followed by acid-catalyzed ring opening gave the 9-cis-aldehyde 9. Wittig-Horner olefination and saponification afforded the title compound in good overall yield and in excellent isotopic purity. (Author)

  12. Ketene as a Reaction Intermediate in the Carbonylation of Dimethyl Ether to Methyl Acetate over Mordenite

    DEFF Research Database (Denmark)

    Rasmussen, Dominik Bjørn; Christensen, Jakob Munkholt; Temel, Burcin

    2015-01-01

    Unprecedented insight into the carbonylation of dimethyl ether over Mordenite is provided through the identification of ketene (CH2CO) as a reaction intermediate. The formation of ketene is predicted by detailed DFT calculations and verified experimentally by the observation of doubly deuterated ...

  13. Alpha-tocopherol disappearance rates from plasma depend on lipid concentrations: Studies using deuterium labeled collard greens in younger and older adults

    Science.gov (United States)

    Little is known about alpha-tocopherol's bioavailability as a constituent of food or its dependence on a subject's age. To evaluate the alpha-tocopherol bioavailability from food, we used collard greens grown in deuterated water (2H collard greens) as a source of deuterium-labeled (2H) alpha-tocophe...

  14. Liquid chromatography-tandem mass spectrometric assay for the simultaneous determination of the irreversible BTK inhibitor ibrutinib and its dihydrodiol-metabolite in plasma and its application in mouse pharmacokinetic studies

    NARCIS (Netherlands)

    Rood, Johannes J M; van Hoppe, Stephanie; Schinkel, Alfred H.; Schellens, Jan H M; Beijnen, Jos H.; Sparidans, Rolf W.

    2016-01-01

    A validated simple, fast and sensitive bio-analytical assay for ibrutinib and its dihydrodiol metabolite in human and mouse plasma was set up. Sample preparation was performed by protein precipitation, and addition of the respective deuterated internal standards, followed by LC-MS/MS analysis.

  15. Deuterodiacetylmorphine as a marker for use of illicit heroin by addicts in a heroin-assisted treatment program

    NARCIS (Netherlands)

    Klous, Marjolein G.; Rook, Elisabeth J.; Hillebrand, Michel J. X.; van den Brink, Wim; van Ree, Jan M.; Beijnen, Jos H.

    2005-01-01

    In preparation for a treatment program concerning the medical coprescription of heroin and methadone to treatment-resistant addicts in the Netherlands, we studied a novel strategy for monitoring co-use of illicit (nonprescribed) heroin. A deuterated analogue of heroin was added (1:20) to

  16. Phonon Measurements and Model Calculations for Naphtalene-d8

    DEFF Research Database (Denmark)

    Mackenzie, Gordon A.; Pawley, G. S.; Dietrich, O. W.

    1977-01-01

    Measurements of the phonon dispersion curves in naphthalene-d8, (deuteration >99%), taken at 77K are presented. The experiments were done on two crystals, using the triple-axis neutron spectrometers at the medium flux reactor, DR3 at Riso. Most of the external or lattice modes have been measured...

  17. Structure and flexibility of worm-like micelles

    DEFF Research Database (Denmark)

    Jerke, G.; Pedersen, J.S.; Egelhaaf, S.U.

    1997-01-01

    Small-angle neutron scattering and static light scattering experiments have been performed on worm-like micelles formed by soybean lecithin and trace amounts of water in deuterated iso-octane. The structure and flexibility of the aggregates have been investigated as a function of solution...

  18. ESR study of radiation damage in pyrimidines. Progress report, August 1, 1975--April 1, 1976

    International Nuclear Information System (INIS)

    Benson, B.W.

    1976-04-01

    The primary objective of this project is to develop general mechanisms for radiation damage to biomolecules using substituted pyrimidines as a model system. Results this year include a single crystal ESR study of 5-ethyl-5-isopropylbarbituric acid, development of the k-band microwave bridge, dose response measurements on methylated barbituric acid derivatives, and synthesis of several specifically deuterated uracil derivatives

  19. Synthesis and Characterization of Furanic Compounds

    Science.gov (United States)

    2013-09-01

    Furanamine. Solvent 2-Furanamine Acetone — Chloroform — Dimethylacetamide (DMAc) — Dimethylsulfoxide ( DMSO ) + Methanol ± Tetrahydrofuran (THF...4 Figure 4. 1 H NMR of 2-Furanamine in D2O solvent ...Spectra for the furanic compounds were obtained in a 0.1%–0.5% deuterated solvent solutions. 3. Synthesis 3.1 General The following monomers and

  20. Dynamics of water transport and storage in conifers studied with deuterium and heat tracing techniques.

    Science.gov (United States)

    F.C. Meinzer; J.R. Brooks; J.-C. Domec; B.L. Gartner; J.M. Warren; D.R. Woodruff; K. Bible; D.C. Shaw

    2006-01-01

    The volume and complexity of their vascular systems make the dynamics of tong-distance water transport in large trees difficult to study. We used heat and deuterated water (D20) as tracers to characterize whole-tree water transport and storage properties in individual trees belonging to the coniferous species Pseudotsuga menziesii...

  1. Temperature effects on the structure of liquid D-methanol through ...

    Indian Academy of Sciences (India)

    Here, the liquid consists of deuterated methanol and neutron data was collected on the high- diffractometer at Dhruva, BARC. The corrected data at elevated temperatures (BP (boiling point) and double the BP) show that there is a large change in the H-bonded structure of this liquid. The pre-peak or hump, known to be ...

  2. Synthesis, Characterization and Antimicrobial Activities of Some ...

    African Journals Online (AJOL)

    user

    of metal ions with vitamin.111: Synthesis and infrared spectra of metal complexes with pyridoxamine and pyridoxine. Inorg. Chim. Acta, 46, 191-197. Gary, J and Adeyemo, A (1981) Interaction of vitamin B1 with Zn(II), Cd (II) and Hg(II) in. Deuterated Dimethyl Sulfoxide. Inorg. Chim. Acta, 55, 93-98. Gohzalez-vergara, E ...

  3. Photochemistry of Fe2(CO)8(Mu-CH2)

    National Research Council Canada - National Science Library

    Branan, Daniel

    2000-01-01

    ...), and its deuterated analog. We have determined that it behaves similarly to other dimetallic carbonyls in that it eliminates carbon monoxide upon irradiation with high-intensity UV/Visible light to form distinct single and double CO-loss products...

  4. Crystal lattice dependency of the free radicals found in irradiated glycine

    NARCIS (Netherlands)

    Bie, M.J.A. de; Braams, R.

    1969-01-01

    The EPR spectra, and hence the stable free radicals, are different for the - or γ-irradiated α-, β- and γ-crystal forms of polycrystalline glycone. Therefore comparisons of the trideutero-glycine EPR spectrum with the EPR spectra of non-deuterated glycine are open to question

  5. Stress and neutron scattering measurements on linear polymer melts undergoing steady elongational flow

    DEFF Research Database (Denmark)

    Hassager, Ole; Mortensen, Kell; Bach, Anders

    2012-01-01

    We use small-angle neutron scattering to measure the molecular stretching in polystyrene melts undergoing steady elongational flow at large stretch rates. The radius of gyration of the central segment of a partly deuterated polystyrene molecule is, in the stretching direction, increasing...... exhibited by the linear polystyrene melt....

  6. Ultra-high-performance liquid chromatography-tandem mass spectrometry measurement of climbazole deposition from hair care products onto artificial skin and human scalp

    NARCIS (Netherlands)

    Chen, G.; Hoptroff, M.; Fei, X.; Su, Y.; Janssen, H.-G.

    2013-01-01

    A sensitive and specific ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed and validated for the measurement of climbazole deposition from hair care products onto artificial skin and human scalp. Deuterated climbazole was used as the internal

  7. Investigation on silver complexes of novel 1,2,3-triazole linked ...

    Indian Academy of Sciences (India)

    Abstract. The novel derivatives of 1,2,3-triazole linked crown ethers were investigated towards silver(I) ion coordination. The NMR measurements in deuterated methanol in different ratios of ligand and silver cation were studied. The experiments were performed in order to examine the way of binding Ag(I) ion by the ...

  8. Tritium separation factors in distillation and chemical exchange processes

    International Nuclear Information System (INIS)

    Dave, S.M.; Ghosh, S.K.; Sadhukhan, H.K.

    1982-01-01

    The vapour pressures of different isotopic hydrogen, water and ammonia molecules have been calculated. These vapour pressures can be used to evaluate relative volatilities of different species for separation of tritium isotopes by distillation. The equilibrium constants for various exchange reactions involving different deuterated and tritiated species of hydrogen, water and ammonia molecules have also been calculated for different temperatures. (author)

  9. Pramana – Journal of Physics | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    An analysis of neutron diffraction data of liquid deuterated 1-propanol at room temperature to extract its molecular conformation is presented. Being a big molecule with twelve atomic sites, the analysis is tricky and needs careful consideration. The resulting molecular parameters are compared with electron diffraction (gas ...

  10. Quantification of benzoxazinoids and their metabolites in Nordic breads

    DEFF Research Database (Denmark)

    Dihm, Katharina; Vendelbo Lind, Mads; Sundén, Henrik

    2017-01-01

    Benzoxazinoids (Bx) and their metabolites are molecules with suggested health effects in humans, found in cereal grains and consequently in cereal foods. However, to date little is known about the amount of Bx in our diet. In this study, deuterated standards 2-hydroxy-1,4-benzoxazin-3-one (HBOA-d4...

  11. Hydrogen atom scrambling in selectively labeled anionic peptides upon collisional activation by MALDI tandem time-of-flight mass spectrometry

    DEFF Research Database (Denmark)

    Bache, Nicolai; Rand, Kasper Dyrberg; Roepstorff, Peter

    2008-01-01

    have now measured the level of hydrogen scrambling in a deprotonated, selectively labeled peptide using MALDI tandem time-of-flight mass spectrometry. Our results conclusively show that hydrogen scrambling is prevalent in the deprotonated peptide upon collisional activation. The amide hydrogens ((1)H....../(2)H) have migrated extensively in the anionic peptide, thereby erasing the original regioselective deuteration pattern obtained in solution....

  12. Determination of yields of gaseous products of carbohydrates radiolysis by mass spectrometry method. [. gamma. rays

    Energy Technology Data Exchange (ETDEWEB)

    Ivko, A A; Gol' din, S I; Bondarenko, N T; Markevich, S V; Sharpatii, V A [AN SSSR, Moscow. Inst. Khimicheskoj Fiziki

    1977-01-01

    Possible complications are treated involved in the mass spectral study of the radiolytic products of deuterated carbohydrates. A method is proposed suitable for the evaluation of hydrogen isotopes relations and the content of deuterium in water. It has been possible to identify the major gaseous radiolytic products of glucose, polyglucan and dextran, and also to assess their radiation-chemical yields.

  13. Structural studies of three-arm star block copolymers exposed to extreme stretch suggests persistent polymer tube

    DEFF Research Database (Denmark)

    Garvey, Christopher J.; Almdal, Kristoffer; Dorokhin, Andriy

    2018-01-01

    We present structural SANS-studies of a three-armed polystyrene star polymer with short deuterated segments at the end of each arm. We show that the form factor of the three-armed star molecules in the relaxed state agrees with that of the random phase approximation of Gaussian chains. Upon...

  14. Synthesis and Characterization of Novel Dimeric Ionic Liquids by Conventional Approaches

    Directory of Open Access Journals (Sweden)

    Yatimah Alias

    2008-07-01

    Full Text Available The 1H-NMR shifts of the imidazolium protons of some novel dimeric ionic liquids were examined in various deuterated solvents. Interactions between the solvent and the imidazolium salt of butyl substituted ionic liquids were observed to give higher chemical shifts than methyl substitution.

  15. Characterisation of spin-waves in copper(II) deuteroformate tetradeuterate: A square ¤S¤=1/2 Heisenberg antiferromagnet

    DEFF Research Database (Denmark)

    Clarke, S.J.; Harrison, A.; Mason, T.E.

    1999-01-01

    Copper(II) formate tetrahydrate (CFTH) is a model square S = 1/2 Heisenberg antiferromagnet with T-N = 16.54 +/- 0.05 K. The dispersion of spin-waves in the magnetic layers of a fully deuterated sample of this material has been mapped at 4.3 K by inelastic neutron scattering from the zone centre ...

  16. Conformational and tautomeric eccentricities of 2-acetyl-1,8-dihydroxynaphthalenes

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Kamounah, Fadhil S.; Hansen, Bjarke Knud Vilster

    2007-01-01

    -range hydrogen-hydrogen coupling between the OH-1 and the OH-8 and by the isotope effects on 13C caused by deuteration at the CH3C=O methyl group. Compound 2 participates in a degenerate equilibrium between two equivalent nonsymmetrical rotamers (2A and 2B) , each having two intramolecular O...HO hydrogen bonds...

  17. Structures and Fragmentation Mechanisms of the Ions of Ethanol by Triple Quadrupole Mass Spectrometry.

    Science.gov (United States)

    1982-07-15

    structural information contained in deuterated sp ies is readily obtainable. Eth 1 ions ty stdied tnc) Vde (CH3CHOH?’., [CH CHOHJ. (CH2COH]r-% [CH 2COF...high and low energy systems involves electronic 18 and vibrational 19 excitation respectively, the amount of energy thus deposited must be approximately

  18. A Raman spectroscopy study on the effects of intermolecular hydrogen bonding on water molecules absorbed by borosilicate glass surface

    Science.gov (United States)

    Li, Fabing; Li, Zhanlong; Wang, Ying; Wang, Shenghan; Wang, Xiaojun; Sun, Chenglin; Men, Zhiwei

    2018-05-01

    The structural forms of water/deuterated water molecules located on the surface of borosilicate capillaries have been first investigated in this study on the basis of the Raman spectral data obtained at different temperatures and under atmospheric pressure for molecules in bulk and also for molecules absorbed by borosilicate glass surface. The strongest two fundamental bands locating at 3063 cm-1 (2438 cm-1) in the recorded Raman spectra are assigned here to the Osbnd H (Osbnd D) bond stretching vibrations and they are compared with the corresponding bands observed at 3124 cm-1 (2325 cm-1) in the Raman spectrum of ice Ih. Our spectroscopic observations have indicated that the structure of water and deuterated water molecules on borosilicate surface is similar to that of ice Ih (hexagonal phase of ice). These observations have also indicated that water molecules locate on the borosilicate surface so as to construct a bilayer structure and that strong and weak intermolecular hydrogen bonds are formed between water/deuterated molecules and silanol groups on borosilicate surface. In accordance with these findings, water and deuterated water molecules at the interface of capillary have a higher melting temperature.

  19. Determination of yields of gaseous products of carbohydrates radiolysis by mass spectrometry method

    International Nuclear Information System (INIS)

    Ivko, A.A.; Gol'din, S.I.; Bondarenko, N.T.; Markevich, S.V.; Sharpatyj, V.A.

    1977-01-01

    Possible complications are treated involved in the mass spectral study of the radiolytic products of deuterated carbohydrates. A method is proposed suitable for the evaluation of hydrogen isotopes relations and the content of deuterium in water. It has been possible to identify the major gaseous radiolytic products of glucose, polyglucan and dextran, and also to assess their radiation-chemical yields [ru

  20. Apparent molar volumes, isobaric expansion coefficients, and isentropic compressibilities, and their H/D isotope effects for some aqueous carbohydrate solutions

    International Nuclear Information System (INIS)

    Bernal, P.J.; Van Hook, W.A.

    1986-01-01

    The molar volumes, isobaric expansion coefficients, and isentropic compressibilities of solutions of a number of carbohydrates and their deuterated isomers were determined in H 2 O and D 2 O between 288.15 and 328.15 K and over a wide range of solute-to-solvent mole ratios. The results are discussed in terms of the specific hydration model. (author)

  1. Temperature dependence of (+)-catechin pyran ring proton coupling constants as measured by NMR and modeled using GMMX search methodology

    Science.gov (United States)

    Fred L. Tobiason; Stephen S. Kelley; M. Mark Midland; Richard W. Hemingway

    1997-01-01

    The pyran ring proton coupling constants for (+)-catechin have been experimentally determined in deuterated methanol over a temperature range of 213 K to 313 K. The experimental coupling constants were simulated to 0.04 Hz on the average at a 90 percent confidence limit using a LAOCOON method. The temperature dependence of the coupling constants was reproduced from the...

  2. Molecular conformation and liquid structure of 2-propanol through ...

    Indian Academy of Sciences (India)

    The neutron diffraction data analysis of deuterated liquid 2-propanol at room temperature to ... 2-Propanol being a large molecule with twelve atomic sites, the conformation analysis is tricky ... A Sahoo1 S Sarkar1 P S R Krishna2 R N Joarder1.

  3. NIST-Traceable NMR Method to Determine Quantitative Weight Percentage Purity of Nitrogen Mustard HN-3 Feedstock Samples

    Science.gov (United States)

    2013-08-01

    products . This report may not be cited for purposes of advertisement. This report has been approved for public release. Acknowledgments The...such as 0.01% ethylbenzene in deuterated acetone can be analyzed to check the signal response. The analysis of this sample can be done periodically as

  4. NIST-Traceable NMR Method to Determine Quantitative Weight Percentage Purity of Nitrogen Mustard HN-1 Feedstock Samples

    Science.gov (United States)

    2014-06-01

    constitute an official endorsement of any commercial products . This report may not be cited for purposes of endorsement. The text of this report is...such as 0.01% ethylbenzene in deuterated acetone can be analyzed to check the signal response on a continuing basis. This analysis can be done

  5. The Structural Phase Transition in Solid DCN

    DEFF Research Database (Denmark)

    Dietrich, O. W.; Mackenzie, Gordon A.; Pawley, G. S.

    1975-01-01

    Neutron scattering measurements on deuterated hydrogen cyanide have shown that the structural phase change from a tetragonal to an orthorhombic form at 160K is a first-order transition. A transverse acoustic phonon mode, which has the symmetry of the phase change, was observed at very low energies...

  6. The role of the C8 proton of ATP in the regulation of phosphoryl transfer within kinases and synthetases

    CSIR Research Space (South Africa)

    Kenyon, CP

    2011-07-01

    Full Text Available Kinase and synthetase enzymes utilise C8D-ATP in preference to non-deuterated ATP. The KIE obtained at low ATP concentrations is clearly a primary KIE demonstrating strong evidence that the bond to the isotopically substituted hydrogen is being...

  7. Liquid chromatography-tandem mass spectrometric assay for the quantitative determination of the tyrosine kinase inhibitor quizartinib in mouse plasma using salting-out liquid-liquid extraction

    NARCIS (Netherlands)

    Retmana, Irene A; Wang, Jing; Schinkel, Alfred H; Schellens, Jan H M; Beijnen, Jos H; Sparidans, Rolf W

    2017-01-01

    A bioanalytical assay for quizartinib -a potent, and selective FLT3 tyrosine kinase inhibitor- in mouse plasma was developed and validated. Salting-out assisted liquid-liquid extraction (SALLE), using acetonitrile and magnesium sulfate, was selected as sample pretreatment with deuterated quizartinib

  8. ESR study on hydrogen-atom abstraction in cryogenic organic solids

    International Nuclear Information System (INIS)

    Ichikawa, Tsuneki

    1995-01-01

    The present paper summarizes our recent results on the hydrogen-atom abstraction from protiated alkane molecule by deuterium atoms in cryogenic deuterated organic solids, obtained by the X-band ESR and electron spin-echo measurements of the product alkyl radicals at cryogenic temperatures. (J.P.N.)

  9. Preparation and certification of solutions of perdeuterated polycyclic aromatic compounds intended for use as surrogate internal standards

    International Nuclear Information System (INIS)

    Quilliam, M.A.; Hardstaff, W.R.; Anacleto, J.F.; LeBlanc, M.D.; Stergiopoulos, V.; Dick, K.L.; Bowser, M.T.; Curtis, J.M.; Embree, D.J.; Sim, P.G.; Boyd, R.K.

    1994-01-01

    Two standard solutions of deuterated polycyclic aromatic compounds (PACs) have been prepared for use as surrogate internal standards. Solution DPAC-1 contains 21 deuterated PACs, and is intended for use with mass spectrometric (MS) detection. Most of the difficulties in certifying concentrations in DPAC-1 arose from the fact that none of the individual compounds was 100% deuterated, so that effects of mass spectrometric fragmentation are convoluted with those of isotopic distributions. The best methods are discussed for using such internal standards so as to minimize these problems, together with those arising from kinetic isotope effects. Solution DPAC-2 contains 6 deuterated PACs, and is primarily intended for use with reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection (FLD, dural programmed wavelength mode), in which the signals for analyte and internal standard are separated chromatographically rather than via the detector. Full details of the preparation of these solutions are described. In addition, examples of their use in the analysis of a certified coal-tar extract (NIST SRM 1597) are described briefly. In one example a novel HPLC-MS technique was employed, and in the other the HPLC-FLD technique was used. (orig.)

  10. Determination of 19 drugs of abuse and metabolites in whole blood by high-performance liquid chromatography-tandem mass spectrometry

    DEFF Research Database (Denmark)

    Bjørk, Marie Kjaergaard; Nielsen, Marie K K; Markussen, Lotte Ø

    2010-01-01

    using mixed-mode columns (Isolute Confirm HCX). Deuterated analogues were used as internal standards for all analytes, except for ketobemidone and O-desmethyltramadol. The analytes were separated by a methanol/ammonium formate gradient using high-performance LC (Agilent HPLC 1100) with a 3 mm x 100 mm...

  11. General methods for the preparation of α and/or β deuterium labelled 6-hydroxydopamine derivatives

    International Nuclear Information System (INIS)

    Borchardt, R.T.; Simmons, J.E.

    1982-01-01

    A convenient method for the synthesis of 6-hydroxydopamine and its phenethylamine derivatives has been developed. Mono-and di-deuteration has been accomplished using sodium borodeuteride and sodium borohydride in the presence of a deuterium source. (U.K.)

  12. Synthesis of leukotrienes labelled with deuterium: [11,12,14,15-2H4]-LTA4, -LTC4, -LTD4 and -LTE4

    International Nuclear Information System (INIS)

    Lellouche, J.P.; Aubert, F.; Noel, J.P.; Boullais, C.; Beaucourt, J.P.

    1989-01-01

    Semi-hydrogenation by D 2 gas on Lindlar catalyst of an acetylenic precursor led to [11,12,14,15- 2 H 4 ]-LTA 4 methyl ester. Nucleophilic opening of the epoxide ring by amino thioacids accorded, after saponification, the corresponding deuterated peptidoleukotrienes LTC 4 , LTD 4 and LTE 4 . (author)

  13. Dynamics of solid alanine by means of nuclear magnetic resonance relaxometry

    Science.gov (United States)

    Kubica-Misztal, A.; Rochowski, P.; Florek-Wojciechowska, M.; Kruk, D.

    2017-04-01

    1H nuclear magnetic resonance relaxometry was applied to investigate the dynamics of l-alanine in the solid phase (powder). The experimental studies were carried out in a very broad frequency range, covering four orders of magnitude—from 4 kHz to 40 MHz (referring to the 1H resonance frequency) in order to probe motional processes of much different time scales by a single experiment. To get access to the dynamics of different proton groups of alanine, the 1H spin-lattice relaxation measurements were performed for non-deuterated and partially deuterated alanine. The experiments were carried out in the temperature range of 293 K-370 K (non-deuterated alanine) and 318 K-370 K (partially deuterated alanine). As a result of a thorough theoretical analysis of the extensive set of experimental results, three motional processes occurring on different time scales are identified and quantitatively described. The slowest process occurs on a time scale of μs and it is attributed to the collective dynamics of a 3D hydrogen bond network of alanine, while the intermediate, attributed to the dynamics of the NH3 group, corresponds to the range of tenths of ns. The fast process describes the rotation of the CH3 group.

  14. Macromolecular neutron crystallography at the Protein Crystallography Station (PCS)

    OpenAIRE

    Kovalevsky, Andrey; Fisher, Zoe; Johnson, Hannah; Mustyakimov, Marat; Waltman, Mary Jo; Langan, Paul

    2010-01-01

    The Protein Crystallography Station user facility at Los Alamos National Laboratory not only offers open access to a high-performance neutron beamline, but also actively supports and develops new methods in protein expression, deuteration, purification, robotic crystallization and the synthesis of substrates with stable isotopes and provides assistance with data-reduction and structure-refinement software and comprehensive neutron structure analysis.

  15. NMR imaging studies of coal

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Z.R.; Zhang, P.Z.; Ding, G.L.; Li, L.Y.; Ye, C.H. [University of Science and Technology, Beijing (China). Dept. of Chemistry

    1996-06-01

    The permeation transportation and swelling behavior of solvents into coal are investigated by NMR imaging using pyridine-d{sub 5} and acetone-d{sub 6}. Images of coal swollen with deuterated solvents illuminate proton distributions of mobile phases within the coal macromolecular networks. More information about the chemical and physical structure of coal can be obtained using NMR imaging techniques.

  16. E. ROETS~, C. GOVAERTS~, H. CHEPKWONY~ AND R. BUSS ON ...

    African Journals Online (AJOL)

    Sigma Chemical Company (St. Louis, MI,. U.S.A.). The rest of the reagents were laboratory reagent grade, from BDH ... Vnmr version 6.lb was used throughout. The measurements were performed in deuterated .... dose level and six control rats received 0.2 ml of the vehicle. Twenty-four hours after the last dose, the uterine ...

  17. The Catalytic Role of Coronene for Molecular Hydrogen Formation

    DEFF Research Database (Denmark)

    Mennella, Vito; Hornekær, Liv; Thrower, John

    2012-01-01

    We present the results of an experimental study on the interaction of atomic deuterium with coronene films. The effects of D atom irradiation have been analyzed with infrared spectroscopy. The spectral changes provide evidence for deuteration of the outer edge coronene C sites via a D addition re...

  18. Femtosecond spectroscopic study of the solvation of amphiphilic molecules by water

    NARCIS (Netherlands)

    Rezus, Y.L.A.; Bakker, H.J.

    2008-01-01

    We use polarization-resolved mid-infrared pump-probe spectroscopy to study the aqueous solvation of proline and N-methylacetamide. These molecules serve as models to study the solvation of proteins. We monitor the orientational dynamics of partly deuterated water molecules (HDO) that are present at

  19. Synthesis of specific deuterium labeled tyrosine and phenylalanine derivatives and their use in the total synthesis of [8-arginine]vasopressin derivatives: the separation of diastereomeric [8-arginine]vasopressin derivatives by partition chromatography

    International Nuclear Information System (INIS)

    Yamamoto, D.M.; Upson, D.A.; Linn, D.K.; Hruby, V.J.

    1977-01-01

    Derivatives of tyrosine specifically deuterated at the α carbon ([α- 2 H 1 ]tyrosine) and at both the α and β carbons ([α,β,β- 2 H 3 ]tyrosine) and a derivative of phenylalanine specifically deuterated at the α carbon ([α- 2 H 1 ]phenylalanine) have been synthesized in high yield. These labeled compounds have been resolved enzymatically, and the enantiomers and racemates have been converted to N-tert-butyloxycarbonyl derivatives. The deuterium labels were not exchanged under the conditions of the syntheses. The protected derivatives as well as specifically deuterated derivatives of S-benzylcysteine and of glycine were used to prepare specifically deuterated analogues of [8-arginine] vasopressin using solid phase peptide procedures. The use of improved synthetic procedures resulted in considerable improvements in the yields of [8-arginine]vasopressin compared with previous reports. In addition, new solvent systems for partition chromatography purification of [8-arginine]vasopressin on Sephadex were developed which allowed a facile one-step separation of diastereomers of [8-arginine]vasopressin containing a racemic amino acid at either the 1-hemicystine or the 2-tyrosine positions of the hormone

  20. Contribution to the study of the structure and reactivity of ketones using deuterium substitution of the α - ketone hydrogens

    International Nuclear Information System (INIS)

    Frejaville, G.

    1966-02-01

    This work is an attempt to obtain more knowledge about the structure and the reactivity of ketones; it is also a contribution to conformational analysis based on infrared signals associated with the C-D vibration in mono-deuterated compounds. In the first chapter the various dosage and synthetic methods used in this work are described. In the second chapter the infrared spectra in the 2100-2200 cm -1 region for mono-deuterated ketones are interpreted on the basis of a simple model. This model is then studied in detail, and also critically and precisely, in the case of the mono deuterated acetone molecule. In the third chapter is studied the mechanism of the Favorskii reaction and the reactivity of all the α-ketonic hydrogens of 2 chloro-cyclohexanone are classified. In a technical appendix is described a counter-current exchange method for obtaining a great variety of solvents and deuterated pure raw materials under advantageous conditions. (author) [fr