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Sample records for 2 3 5

  1. Synthesis of enantiomerically pure (2S,3S)-5,5,5-trifluoroisoleucine and (2R,3S)-5,5,5-trifluoro-allo-isoleucine

    PubMed Central

    Huhmann, Susanne; Gerling, Ulla I M; Lentz, Dieter

    2013-01-01

    Summary A practical route for the stereoselective synthesis of (2S,3S)-5,5,5-trifluoroisoleucine (L-5-F3Ile) and (2R,3S)-5,5,5-trifluoro-allo-isoleucine (D-5-F3-allo-Ile) was developed. The hydrophobicity of L-5-F3Ile was examined and it was incorporated into a model peptide via solid phase peptide synthesis to determine its α-helix propensity. The α-helix propensity of 5-F3Ile is significantly lower than Ile, but surprisingly high when compared with 4’-F3Ile. PMID:24204411

  2. Synthesis of enantiomerically pure (2S,3S)-5,5,5-trifluoroisoleucine and (2R,3S)-5,5,5-trifluoro-allo-isoleucine.

    PubMed

    Erdbrink, Holger; Nyakatura, Elisabeth K; Huhmann, Susanne; Gerling, Ulla I M; Lentz, Dieter; Koksch, Beate; Czekelius, Constantin

    2013-01-01

    A practical route for the stereoselective synthesis of (2S,3S)-5,5,5-trifluoroisoleucine (L-5-F3Ile) and (2R,3S)-5,5,5-trifluoro-allo-isoleucine (D-5-F3-allo-Ile) was developed. The hydrophobicity of L-5-F3Ile was examined and it was incorporated into a model peptide via solid phase peptide synthesis to determine its α-helix propensity. The α-helix propensity of 5-F3Ile is significantly lower than Ile, but surprisingly high when compared with 4'-F3Ile. PMID:24204411

  3. 2,2\\',3,3\\',4,4\\',5,5\\',6,6\\'-Decabromodiphenyl ether (BDE-209)

    Integrated Risk Information System (IRIS)

    2,2 ' , 3,3 ' , 4,4 ' , 5,5 ' , 6,6 ' - Decabromodiphenyl ether ( BDE - 209 ) ; CASRN 1163 - 19 - 5 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process

  4. 1s2s2p2 5p3 5S transition in B ii

    NASA Astrophysics Data System (ADS)

    Mannervik, S.; Cederquist, H.; Martinson, I.; Brage, T.; Froese Fischer, C.

    1987-04-01

    An experimental and theoretical study has been made of the 1s2s2p2 5P-1s2p3 5S transition in B ii. The experimental wavelength and lifetime (1323.92+/-0.07 Å and 0.65+/-0.01 ns), determined by beam-foil spectroscopy, are more than five times more accurate than previous experimental results. Our theoretical data, from multiconfiguration Hartree-Fock calculations, 1311.6 Å and 0.601 ns, are in excellent agreement with previous theoretical predictions of Beck and Nicolaides [Phys. Lett. 61A, 227 (1977)]. We have also observed the 1s2p3 5S-1s2p23s 5P transition, at 857.7+/-0.2 Å, in accord with the theoretical value 859.1 Å.

  5. 10 CFR 960.5-2-3 - Meteorology.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Meteorology. 960.5-2-3 Section 960.5-2-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Preclosure Guidelines Preclosure Radiological Safety § 960.5-2-3 Meteorology. (a)...

  6. 10 CFR 960.5-2-3 - Meteorology.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Meteorology. 960.5-2-3 Section 960.5-2-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Preclosure Guidelines Preclosure Radiological Safety § 960.5-2-3 Meteorology. (a)...

  7. 10 CFR 960.5-2-3 - Meteorology.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Meteorology. 960.5-2-3 Section 960.5-2-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Preclosure Guidelines Preclosure Radiological Safety § 960.5-2-3 Meteorology. (a)...

  8. 10 CFR 960.5-2-3 - Meteorology.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Meteorology. 960.5-2-3 Section 960.5-2-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Preclosure Guidelines Preclosure Radiological Safety § 960.5-2-3 Meteorology. (a)...

  9. 10 CFR 960.5-2-3 - Meteorology.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Meteorology. 960.5-2-3 Section 960.5-2-3 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Preclosure Guidelines Preclosure Radiological Safety § 960.5-2-3 Meteorology. (a)...

  10. 40 CFR 721.10433 - Cyclopentene, 1,2,3,3,4,4,5,5-octafluoro-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ....80(f) and (j) (dry etching agent and chemical vapor deposition agent for the production of...) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10433 Cyclopentene, 1,2,3,3,4,4,5,5-octafluoro-. (a) Chemical...

  11. 40 CFR 721.10433 - Cyclopentene, 1,2,3,3,4,4,5,5-octafluoro-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ....80(f) and (j) (dry etching agent and chemical vapor deposition agent for the production of...) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10433 Cyclopentene, 1,2,3,3,4,4,5,5-octafluoro-. (a) Chemical...

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

    USGS Publications Warehouse

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

    1944-01-01

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

  13. 21 CFR 176.230 - 3,5-Dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false 3,5-Dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione. 176.230 Section 176.230 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: PAPER...

  14. 13. PRATT STREET BULKHEAD: SECTIONS 2, 3, 4, 5, AND ...

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

    13. PRATT STREET BULKHEAD: SECTIONS 2, 3, 4, 5, AND 6, DRAWER 10, PLAN NO. 1, 1 IN. = 15 FT. AND 1/2 IN. = 1 FT., APRIL 25, 1906, DRAWING SHOWS DESIGN FOR PRATT STREET BULKHEAD BETWEEN PIERS - Baltimore Inner Harbor, Pier 5, South of Pratt Street between Market Place & Concord Street, Baltimore, Independent City, MD

  15. ANCHOR SETTING PLAN FOR PIERS 1, 2, 3, 4, 5 ...

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

    ANCHOR SETTING PLAN FOR PIERS 1, 2, 3, 4, 5 AND 6, APALACHICOLA RIVER BRIDGE, SHEET 5505 TO 8-M1 - Apalachicola River Bridge, State Route 20 spanning the Apalachicola River, Blountstown, Calhoun County, FL

  16. 21 CFR 176.230 - 3,5-Dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true 3,5-Dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione. 176.230 Section 176.230 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: PAPER AND PAPERBOARD COMPONENTS Substances for Use Only...

  17. 21 CFR 176.230 - 3,5-Dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false 3,5-Dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione. 176.230 Section 176.230 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: PAPER AND PAPERBOARD COMPONENTS Substances for Use Only...

  18. 21 CFR 176.230 - 3,5-Dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false 3,5-Dimethyl-1,3,5,2H-tetrahydrothiadiazine-2-thione. 176.230 Section 176.230 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: PAPER AND PAPERBOARD COMPONENTS Substances for Use Only...

  19. 3-Benzyl-5-methyl-1,2-benzoxazole 2-oxide

    PubMed Central

    Anuradha, G.; Gopalsamy, Vasuki; Veera Reddy, A.; Laxminarasimhulu, G.

    2012-01-01

    In the title compound, C15H13NO2, the isoxazole unit and the attached benzene ring are almost coplanar, making a dihedral angle of 1.42 (8)°. The benzyl ring is inclined to the isoxazole ring by 74.19 (8)° and is in a +sc conformation with respect to the benzisoxazole unit. In the crystal, C—H⋯O hydrogen bonds link the mol­ecules, forming zigzag chains propagating along the b axis. There are also π–π inter­actions present involving the isoxazole and benzyl rings [centroid–centroid distance = 3.5209 (10) Å], and C—H⋯π inter­actions involving the benzene ring of the benzoisoxazole unit and the methyl­ene bridging group. PMID:23125740

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

    DOEpatents

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

    1991-03-05

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

  1. A low Km nucleoside 3'(2'),5-bisphosphate 3'(2')-phosphohydrolase from rat liver.

    PubMed

    Meireles Ribeiro, J; Ruiz, A; Sillero, A; Günther Sillero, M A

    1990-04-01

    In the course of an investigation on the occurrence in rat liver of a specific hydrolytic activity on adenosine 2',5'-bisphosphate, a nucleoside 3'(2'),5'-bisphosphate 3'(2')-phosphohydrolase was purified following standard procedures. The enzyme hydrolyzes the phosphate group joined to the 3' or the 2' position of the following nucleotides (relative velocities indicated in brackets): PAdoP (100), PCydP (95), PGuoP (80), PAdo2'P (40), PdAdoP (4), SPAdoP (18). Other nucleotides were not substrates of the reaction: NADP+, PAdoPP, PPGuoP, AdoP, PAdo, GuoP, PGuo, ADP, ATP, cAMP, adenosine(3')phospho(5')adenosine. The Km values determined for PAdoP and PAdo2'P were 10 and 7 microM, respectively. Two isoforms were separated by chromatography on a Mono Q column. Both isoforms were kinetically indistinguishable, presenting a pI value of 5.35, a molecular mass of 38 kDa, pH optimum of 8.0, and strictly required Mg2+ or Mn2+. An enzymatic activity similar to the one described here has already been reported in guinea pig liver [5]. These authors however only obtained 1 enzymatic form with Km values of 3.1 and 1.8 mM for PAdoP and PAdo2'P, respectively. The potential physiological role of this enzyme in the metabolism of sulphate is also considered. The previously registered number EC 3.1.3.7 could be applied to this activity. PMID:2166593

  2. 10 CFR 960.3-2-2-5 - Formal site nomination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Formal site nomination. 960.3-2-2-5 Section 960.3-2-2-5 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-5 Formal site nomination. After the...

  3. 10 CFR 960.3-2-2-5 - Formal site nomination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Formal site nomination. 960.3-2-2-5 Section 960.3-2-2-5 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-5 Formal site nomination. After the...

  4. 10 CFR 960.3-2-2-5 - Formal site nomination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Formal site nomination. 960.3-2-2-5 Section 960.3-2-2-5 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-5 Formal site nomination. After the...

  5. 10 CFR 960.3-2-2-5 - Formal site nomination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Formal site nomination. 960.3-2-2-5 Section 960.3-2-2-5 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-5 Formal site nomination. After the...

  6. 10 CFR 960.3-2-2-5 - Formal site nomination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Formal site nomination. 960.3-2-2-5 Section 960.3-2-2-5 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE REPOSITORY Implementation Guidelines § 960.3-2-2-5 Formal site nomination. After the...

  7. Down conversion of Er3+-Yb3+ couple in Y2BaZnO5

    NASA Astrophysics Data System (ADS)

    Xia, Wenbin; Jin, Xiangliang; Yang, Xiaoliang; Xiao, Siguo

    2016-04-01

    Er3+-Yb3+ co-doped Y2BaZnO5 phosphors were synthesized via high temperature solid-state reaction method. The quantum cutting properties for Er3+-Yb3+ co-doped Y2BaZnO5 phosphors have been detailedly exploited under different wavelength excitation. Unlike in fluoride host, only the Er(4S3/2) + Yb(2F7/2) → Er(4I13/2) + Yb(2F5/2) energy transfer process in Y2BaZnO5 effectively performs the down-conversion, which can split an absorbed high-energy photon into two photons of 1000 nm and 1550 nm radiations. The quantum cutting properties of Er3+-Yb3+ couple in Y2BaZnO5 provides meaningful reference in search of new efficient Er3+-Yb3+ co-doped quantum cutting phosphors.

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

    PubMed Central

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

    2014-01-01

    In general, 3,5-diiodothyronine (3,5-T2) increases the resting metabolic rate and oxygen consumption, exerting short-term beneficial metabolic effects on rats subjected to a high-fat diet. Our aim was to evaluate the effects of chronic 3,5-T2 administration on the hypothalamus–pituitary–thyroid axis, body mass gain, adipose tissue mass, and body oxygen consumption in Wistar rats from 3 to 6 months of age. The rats were treated daily with 3,5-T2 (25, 50, or 75 μg/100 g body weight, s.c.) for 90 days between the ages of 3 and 6 months. The administration of 3,5-T2 suppressed thyroid function, reducing not only thyroid iodide uptake but also thyroperoxidase, NADPH oxidase 4 (NOX4), and thyroid type 1 iodothyronine deiodinase (D1 (DIO1)) activities and expression levels, whereas the expression of the TSH receptor and dual oxidase (DUOX) were increased. Serum TSH, 3,3′,5-triiodothyronine, and thyroxine were reduced in a 3,5-T2 dose-dependent manner, whereas oxygen consumption increased in these animals, indicating the direct action of 3,5-T2 on this physiological variable. Type 2 deiodinase activity increased in both the hypothalamus and the pituitary, and D1 activities in the liver and kidney were also increased in groups treated with 3,5-T2. Moreover, after 3 months of 3,5-T2 administration, body mass and retroperitoneal fat pad mass were significantly reduced, whereas the heart rate and mass were unchanged. Thus, 3,5-T2 acts as a direct stimulator of energy expenditure and reduces body mass gain; however, TSH suppression may develop secondary to 3,5-T2 administration. PMID:24692290

  9. Optical cooling in Er3+:KPb2Cl5.

    PubMed

    Condon, Nicholas J; Bowman, Steven R; O'Connor, Shawn P; Quimby, Richard S; Mungan, Carl E

    2009-03-30

    For the first time, optical cooling has been observed in the (4)I(13/2) excited state of erbium(III), using the low phonon energy host materal, potassium lead chloride (KPb(2)Cl(2)). Cooling was observed when samples were pumped at wavelengths longer than 1557 nm, 17 nm longer than the mean fluorescence wavelength of 1540 nm, which implies a nonradiative heat load of 1.1% for the (4)I(13/2)-->(4)I(15/2) transition. When pumped at 1568 nm, the total cooling efficiency was 0.38% of the absorbed power. These results highlight the potential of Er(3+):KPb(2)Cl(5) as a material for lasers operating in an eye safe spectral region. PMID:19333313

  10. Atomic parameters for the 2{p}^{5}3p\\;{}^{2}{[3/2]}_{2}-2{p}^{5}3s\\;{}^{2}{[3/2]}_{2}^{o} transition of Ne I relevant in nuclear physics

    NASA Astrophysics Data System (ADS)

    Li, Jiguang; Godefroid, Michel; Wang, Jianguo

    2016-06-01

    We calculated the magnetic dipole hyperfine interaction constants and the electric field gradients of 2{p}53p{}2{[3/2]}2 and 2{p}53s{}2[3/2{]}2o levels of Ne I by using the multiconfiguration Dirac–Hartree–Fock method. The electronic factors contributing to the isotope shifts were also estimated for the λ =614.5 {{nm}} transition connecting these two states. Electron correlation and relativistic effects including the Breit interaction were investigated in detail. Combining with recent measurements, we extracted the nuclear quadrupole moment values for 20Ne and 23Ne with a smaller uncertainty than the current available data. Isotope shifts in the 2{p}53p{}2{[3/2]}2-2{p}53s{}2[3/2{]}2o transition based on the present calculated field- and mass-shift parameters are in good agreement with the experimental values. However, the field shifts in this transition are two or three orders of magnitude smaller than the mass shifts, making rather difficult to deduce changes in nuclear-charge mean-square radii. According to our theoretical predictions, we suggest using instead transitions connecting levels arising from the 2p53s configuration to the ground state, for which the normal mass shift and specific mass shift contributions counteract each other, producing relatively small mass shifts that are only one order of magnitude larger than relatively large field shifts, especially for the 2{p}53s{}2[1/2{]}1o-2{p}6{}1{S}0 transition.

  11. Fermiology of Ce2 Rh3 Ge5

    NASA Astrophysics Data System (ADS)

    Wartenbe, Mark

    The competition between localized and delocalized f electrons in heavy fermion materials produces a wide variety of interesting physical phenomena. Among these compounds is Ce2Rh3Ge5. This heavy-fermion system undergoes an antiferromagnetic transition below 4K and exhibits an angle dependent magnetic phase transition around 25 tesla. In addition, RF conductivity measurements in pulsed field (65T) have revealed quantum oscillations. Temperature dependence at fixed angle indicates relatively heavy effective masses of values ranging from ~3me on up to ~10me. This indicates that the narrow f-electron density of states is partially hybridized close to the Fermi energy, but also places strict cryogenic constraints upon the measurement (3Helium temperatures are required). Fermi surface calculations have produced complex figures which lend validation to such rich behavior. Presented are updated measurements including magnetization and revised theoretical calculations..

  12. Propellant Containing 3, 6bis(1h-1,2,3,4-Tetrazol-5-Ylamino)-1,2,4,5- Tetrazine Or Salt Thereof

    DOEpatents

    Hiskey, Michael A.; Chavez, David E.; Naud, Darren

    2003-12-02

    The compound 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine and its salts are provided together with a propellant composition including an oxidizer, a binder and 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine or its salts.

  13. Microwave dielectric properties of (A2+(1/3)B5+(2/3))0.5Ti0(0.5)O2 (A2+ = Zn, Mg, B5+ = Nb, Ta) ceramics.

    PubMed

    Kim, E S; Kang, D H

    2008-05-01

    Dielectric properties of (A(2+)(1/3)B(5+)(2/3))(0.5)Ti0(0.5)O(2) (A(2+) = Zn, Mg, B(5+) = Nb, Ta) ceramics were investigated at microwave frequencies. A single phase with tetragonal rutile structure was obtained through the entire compositions. Dielectric properties were strongly dependent on the structural characteristics. The specimens with B(5+) = Nb showed a larger dielectric constant than those with B(5+) = Ta due to the decrease of bond valence. Quality factors (Qf) of the specimens with B(5+) = Ta were larger than those with B(5+) = Nb. Temperature coefficient of the resonant frequencies (TCF) of (Zn(1/3)Nb(2/3) )0(0.5)Ti0(0.5)O(2) was larger than that of (Mg(1/3)Ta(2/3))0(0.5)Ti0(0.5)O(2). These results could be attributed to the changes of the temperature coefficient of dielectric constant and the degree of oxygen octahedral distortion. PMID:18519214

  14. Crystalline 1H-1,2,3-triazol-5-ylidenes

    DOEpatents

    Bertrand, Guy; Gulsado-Barrios, Gregorio; Bouffard, Jean; Donnadieu, Bruno

    2016-08-02

    The present invention provides novel and stable crystalline 1H-1,2,3 triazolium carbenes and metal complexes of 1H-1,2,3 triazolium carbenes. The present invention also provides methods of making 1H-1,2,3 triazolium carbenes and metal complexes of 1H-1,2,3 triazolium carbenes. The present invention also provides methods of using 1H-1,2,3 triazolium carbenes and metal complexes of 1H-1,2,3 triazolium carbenes in catalytic reactions.

  15. Synthesis of 5-chloro-4,5-diaryl-. delta. /sup 3/-1,3-oxazolin-2-ones

    SciTech Connect

    Bal'on, Ya.G.; Smirnov, V.A.

    1987-09-20

    During an attempt at the synthesis of the oxazoles by the reactions of the oxazolines (I) with phosphorus pentachloride the authors obtained the 5-chloro-4,5-diaryl-..delta../sup 3/-1,3-oxazolin-2-ones instead of the expected 4,5-diaryl-2-chlorooxazoles. As electrophiles, these compounds are active in nucleophilic addition and substitution reactions. Thus, in their reaction with methanol the 4,5-dimethoxy-4,5-diaryl-1,3-oxazolidin-2-ones are formed with quantitative yields. When heated they are easily converted into 5-methoxy-4,5-diaryl-..delta..-1,3-oxazolin-2-ones. The compositions and structures were proved by IR and PMR spectroscopy and elemental analysis.

  16. Michael Reaction of 3-aAryl-2,4-Dicarboethoxy-5-Hydroxy-5-Methylcyclohexanones

    PubMed Central

    El-Ablack, Fawzia Zakaria; Metwally, M. A.; Khalil, A. M.

    2015-01-01

    Summary The reaction of 3-aryl-2,4-dicarboethoxy-5-hydroxy-5-methylcyclohexanones 1with benzalacetone, dibenzalacetone, benzalacetophenone, and 4-benzal-1-phenyl-3-methyl pyrazolone has been investigated to give Michael compounds 2-5. hydrolysis of the dioxo derivative 4 afforded1,5-dicarbonyl derivative 6which On condensation with hydrazine and/or substituted hydrazine and hydroxylamine produced1,2-diazepine and 1,2-oxazepine derivatives 7,8 respectively. Reaction of β-Keto ester 1 with 1,3-diphenylacetone afforded 9. The structures of the hitherto unknown compounds have been confirmed by analytical and spectral data. The newly synthesized compounds have been screened to test their antimicrobial and antifungal activity. PMID:26689538

  17. Ferroelectric Properties of Ba2Bi4Ti5O18 Doped with Pb2+, Al3+, Ga3+, In3+, Ta5+ Aurivillius Phases

    NASA Astrophysics Data System (ADS)

    Rosyidah, A.; Onggo, D.; Khairurrijal, Ismunandar

    2008-03-01

    In recent years, bismuth layer structured ferroelectrics (BLSFs) have been given much attention because some materials, such as Ba2Bi4Ti5O18, are excellent candidate materials for nonvolatile ferroelectric random access memory (FRAM) applications. BLSFs are also better candidates because of their higher Curie points. Recently, we have carried out computer simulation in atomic scale in order to predict the energies associated with the accommodation of aliovalent and isovalent dopants (Pb2+, Al3+, Ga3+, In3+, Ta5+) in the Aurivillius structure of Ba2Bi4Ti5O18. In this work, the predicted stable phases were synthesized using solid state reactions and their products then were characterized using powder X-ray diffraction method. The cell parameters were determined using Rietveld refinement in orthorhombic system with space group of B2cb. The cell parameters for Ba2Bi4Ti5O18 doped with Pb2+, Al3+, Ga3+, In3+, Ta5+ were a = 5.5006(6) b = 5.4990(5) c = 50.5440(7) Å; a = 5.5012(4) b = 5.4986(8) c = 50.5449(7) Å; a = 5.5006(3) b = 5.4999(3) c = 50.5437(9) Å; a = 5.5007(4) b = 5.4989(7) c = 50.5446(6) Å; and a = 5.5000(5) b = 5.4995(8) c = 50.5436(6) Å. Results from the ferroelectric properties measurement for Ba2Bi4Ti5O18 doped with Pb2+, Al3+, Ga3+, In3+, Ta5+ were Pr = 16.7 μC/cm2, Ec = 35.1 kV/cm; Pr = 15.9 μC/cm2, Ec = 33.8 kV/cm; Pr = 15.6 μC/cm2, Ec = 34.2 kV/cm; Pr = 15.3 μC/cm2, Ec = 34.0 kV/cm; Pr = 16.9 μC/cm2, Ec = 35.6 kV/cm.

  18. Crystal and molecular structure of the coordination compounds of Er3+ with 1-(methoxydiphenylphosphoryl)-2-diphenylphosphorylbenzene [Er L {2/1}(NO3)2]2[Er(NO3)2(H2O)5]0.333(NO3)2.333 · 2.833H2O and its ethyl substituted derivative [Er L {2/2}(NO3)2][Er(NO3)5]0.5 · 0.5H2O

    NASA Astrophysics Data System (ADS)

    Polyakova, I. N.; Baulin, V. E.; Ivanova, I. S.; Pyatova, E. N.; Sergienko, V. S.; Tsivadze, A. Yu.

    2015-01-01

    The coordination compounds of Er3+ with 1-(methoxydiphenylphosphoryl)-2-diphenylphosphorylbenzene [Er L {2/1}(NO3)2]2[Er(NO3)2(H2O)5]0.333(NO3)2.333 · 2.833H2O ( I) and its ethyl substituted derivative [Er L {2/2}(NO3)2][Er(NO3)5]0.5 · 0.5H2O ( II) are synthesized and their crystal structures are studied. I and II contain [Er L 2(NO3)2]+ complex cations of identical composition and close structure. The eight-vertex polyhedron of the Er atom in the shape of a distorted octahedron with two split trans vertices is formed by the O atoms of the phosphoryl groups of L ligands and nitrate anions. L ligands close nine-membered metallocycles. The structures contain spacious channels which are populated differently, namely, by disordered [Er(NO3)2(H2O)5]+ complex cations, NO{3/-} anions, and crystallization water molecules in I and disordered [Er(NO3)5]2- complex anions and crystallization water molecules in II. The IR spectra of I and II are studied.

  19. 2-(2-Chloro-phen-yl)-5-methyl-1,3-dioxane-5-carboxylic acid.

    PubMed

    Jia, Guo-Kai; Yuan, Lin; Zhang, Min; Yuan, Xian-You

    2012-07-01

    In the title compound, C(12)H(13)ClO(4), the 1,3-dioxane ring adopts a chair conformation and the 2-chloro-benzene and methyl substituents occupy equatorial sites. The carboxyl group is in an axial inclination. In the crystal, carb-oxy-lic acid inversion dimers linked by pairs of O-H⋯O hydrogen bonds generate R(2) (2)(8) loops. PMID:22807863

  20. 4-[4-(4-Amino-1,2,5-oxadiazol-3-yl)-1,2,5-oxadiazol-3-yl]-1,2,5-oxadiazol-3-amine

    PubMed Central

    Jia, Si-Yuan; Wang, Bo-Zhou; Fan, Xue-Zhong; Li, Ping; Ng, Seik Weng

    2012-01-01

    The complete molecule of the compound, C6H4N8O3, is generated by a crystallographic twofold rotation axis that runs through the central ring. The flanking ring is twisted by 20.2 (1)° with respect to the central ring. One of the amino H atoms forms an intra­molecular N—H⋯N hydrogen bond; adjacent mol­ecules are linked by N—H⋯N hydrogen bonds forming a chain running along [10-2]. PMID:22590430

  1. 3-(4-Bromo-benzyl-idene)-1,5-dioxaspiro-[5.5]undecane-2,4-dione.

    PubMed

    Zeng, Wu-Lan

    2011-01-01

    The title mol-ecule, C(16)H(15)BrO(4), was prepared by the reaction of (R)-2,4-dioxo-1,5-dioxaspiro-[5.5]undecane and 4-bromo-benzaldehyde with ethanol. The 1,3-dioxane ring exhibits a distorted boat and the fused cyclo-hexane ring exhibits a chair conformation. PMID:21523094

  2. 3-tert-Butyl 5-methyl (2R,4S,5R)-2-(4-methoxyphenyl)-4-(3-nitrophenyl)-1,3-oxazolidine-3,5-dicarboxylate

    PubMed Central

    Montiel-Smith, Sara; Bernès, Sylvain; Sandoval-Ramírez, Jesús; Meza-Reyes, Socorro; Dubois, Joëlle

    2012-01-01

    The title mol­ecule, C23H26N2O8, was synthesized in three steps starting from m-nitro­cinnamic acid. The central oxazolidine ring adopts an almost perfect envelope conformation with the O atom as the flap [puckering parameter ϕ = 0.3 (6)°]. The dihedral angle formed by the benzene rings is 61.81 (9)°. In the crystal, mol­ecules are connected into double chains parallel to [010] by C—H⋯O hydrogen bonds. The absolute configuration was assigned from the synthetic procedure. PMID:23284466

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

    NASA Technical Reports Server (NTRS)

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

    1982-01-01

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

  4. Photoexcitation and photoionization from the 2p53p[5/2]2,3 levels in neon

    NASA Astrophysics Data System (ADS)

    Baig, M. A.; Bokhari, I. A.; Rafiq, M.; Kalyar, M. A.; Hussian, T.; Ali, Raheel; Piracha, N. K.

    2011-07-01

    We present measurements of the excitation spectra from the 2p53p [5/2]3,2 levels in neon using two-step laser excitation and ionization in conjunction with an optogalvanic detection in dc and rf discharge cells. The 2p53p [5/2]3,2 intermediate levels have been approached via the collisionally populated 2p53s [3/2]2 metastable level. The Rydberg series 2p5(2P3/2)nd [7/2]4 (12 ⩽ n ⩽ 44), 2p5(2P3/2)ns [3/2]2 (13 ⩽ n ⩽ 35) and the parity forbidden transitions 2p5(2P3/2)np [5/2]3 (13 ⩽ n ⩽ 19) have been observed from the 2p53p [5/2]3 level, whereas the 2p5(2P3/2)nd [7/2]3 (12 ⩽ n ⩽ 44), 2p5(2P3/2)ns [3/2]2 (13 ⩽ n ⩽ 35), and 2p5(2P1/2)nd' [5/2]3 (9 ⩽ n ⩽ 12) Rydberg series have been observed from the 2p53p[5/2]2 level in accordance with the ΔJ = ΔK = ± 1 selection rules. The photoionization cross sections from the 2p53p [5/2]3 intermediate level have been measured at eight ionizing laser wavelengths (399, 395, 390, 385, 380, 370, 364, and 355 nm) and that from the 2p53p [5/2]2 level at 401.8 nm. These measurements are in excellent agreement with the experimental values reported in the literature, while the experimental data lie much below the theoretically calculated photoionization cross sections curve.

  5. Platelet activating factor antagonist design. 2. X-ray structure of dimethyl 2,3,4,5-tetrahydro-5 beta-(3,4-methylenedioxyphenyl)-2-oxo-3 beta-(3,4,5-trimethoxybenzoyl)-3 alpha,4 alpha-furandicarboxylate.

    PubMed

    Peterson, J R; Do, H D; Rogers, R D

    1989-07-15

    C25H24O12, Mr = 516.46, triclinic, P-1, a = 8.780 (3), b = 11.298 (4), c = 13.271 (6) A, alpha = 71.77 (4), beta = 70.31 (3), gamma = 72.66 (3) degrees, V = 1189 A3, Z = 2, Dx = 1.44 g cm-3, lambda (Mo K alpha) = 0.71073 A, mu = 0.74 cm-1, F(000) = 540, T = 293 K, final R = 0.046 for 2495 observed [Fo greater than or equal to 5 sigma (Fo)] reflections. The observed structure reveals a trans disposition for the methoxycarbonyl and aryl substituents at positions 4 and 5 of the heterocycle and a cis-3,4-bis(methoxycarbonyl) relationship. There is no crystallographically imposed symmetry. Several intermolecular van der Waals interactions occur in the cell lattice of this compound. PMID:2610989

  6. Metabolism of 1,2,3,4-, 1,2,3,5-, and 1,2,4,5-tetrachlorobenzene in the squirrel monkey

    SciTech Connect

    Schwartz, H.; Chu, I.; Villeneuve, D.C.; Benoit, F.M.

    1987-01-01

    The metabolism of three tetrachlorobenzene isomers (TeCB) was investigated in the squirrel monkey. The animals were administered orally 6 single doses of /sup 14/C-labeled 1,2,3,4-, 1,2,4,5-, or 1,2,3,5-tetrachlorobenzene over a 3-wk period at levels ranging from 50 to 100 mg/kg body weight (b.w) and kept in individual metabolism cages to collect urine and feces for radioassay. Approximately 38% (1,2,3,4-TeCB), 36% (1,2,3,5-TeCB), and 18% (1,2,4,5-TeCB) of the doses were excreted respectively in the feces 48 h post administration. In monkeys dosed with 1,2,3,4-TeCB, unchanged compound accounted for 50% of the fecal radioactivity. Unchanged compound accounted for more than 50% of the fecal radioactivity found in the monkeys dosed with 1,2,3,5-TeCB. The fecal metabolites were identified in both groups. No metabolites were detected in the feces of monkeys dosed with 1,2,4,5-TeCB. While the fecal route represented the major route of excretion for 1,2,3,4-TeCB, the other two isomers were eliminated exclusively in the feces. The above data in the squirrel monkey are different from those obtained with the rat and the rabbit, and demonstrate the different metabolic pathways for the isomers.

  7. Protein Phosphatase 2A Regulates Interleukin-2 Receptor Complex Formation and JAK3/STAT5 Activation*

    PubMed Central

    Ross, Jeremy A.; Cheng, Hanyin; Nagy, Zsuzsanna S.; Frost, Jeffrey A.; Kirken, Robert A.

    2010-01-01

    Reversible protein phosphorylation plays a key role in interleukin-2 (IL-2) receptor-mediated activation of Janus tyrosine kinase 3 (JAK3) and signal transducer and activator of transcription 5 (STAT5) in lymphocytes. Although the mechanisms governing IL-2-induced tyrosine phosphorylation and activation of JAK3/STAT5 have been extensively studied, the role of serine/threonine phosphorylation in controlling these effectors remains to be elucidated. Using phosphoamino acid analysis, JAK3 and STAT5 were determined to be serine and tyrosine-phosphorylated in response to IL-2 stimulation of the human natural killer-like cell line, YT. IL-2 stimulation also induced serine/threonine phosphorylation of IL-2Rβ, but not IL-2Rγ. To investigate the regulation of serine/threonine phosphorylation in IL-2 signaling, the roles of protein phosphatase 1 (PP1) and 2A (PP2A) were examined. Inhibition of phosphatase activity by calyculin A treatment of YT cells resulted in a significant induction of serine phosphorylation of JAK3 and STAT5, and serine/threonine phosphorylation of IL-2Rβ. Moreover, inhibition of PP2A, but not PP1, diminished IL-2-induced tyrosine phosphorylation of IL-2Rβ, JAK3, and STAT5, and abolished STAT5 DNA binding activity. Serine/threonine phosphorylation of IL-2Rβ by a staurosporine-sensitive kinase also blocked its association with JAK3 and IL-2Rγ in YT cells. Taken together, these data indicate that serine/threonine phosphorylation negatively regulates IL-2 signaling at multiple levels, including receptor complex formation and JAK3/STAT5 activation, and that this regulation is counteracted by PP2A. These findings also suggest that PP2A may serve as a therapeutic target for modulating JAK3/STAT5 activation in human disease. PMID:19923221

  8. Preparation of 3,3'-azobis(6-amino-1,2,4,5-tetrazine)

    DOEpatents

    Hiskey, Michael A.; Chavez, David E.; Naud, Darren

    2002-01-01

    The compound of the structure ##STR1## where a, b, c, d and e are 0 or 1 and a+b+c+d+e is from 0 to 5 is disclosed together with the species 3,3'-azobis(6-amino-1,2,4,5-tetrazine) and a process of preparing such compounds.

  9. A facile synthesis of new 1,2-dihydro-2 lambda(5)-[1,3]oxazolo[5,4-d][1,3,2]diazaphosphinine derivatives starting from 2-benzoylamino-3,3-dichloroacrylonitrile

    SciTech Connect

    Gakh, Andrei A; Shablykin, Oleg V

    2008-06-01

    Easily accessible 2-benzoylamino-3,3-dichloroacrylonitrile, when treated successively with primary amines, phosphorus pentachloride, sulfur dioxide, and various N- or S-nucleophiles, furnishes the corresponding derivatives of 1,2-dihydro-2{lambda}{sup 5}-[1,3]oxazolo[5,4-d][1,3,2]diazaphosphinine, a novel fused heterocycle. The structure of the compounds obtained is unequivocally confirmed by spectroscopic methods and X-ray diffraction analysis.

  10. 40 CFR 721.5284 - Chromate (5-), bis[4-hydroxy-7-[(2-hydroxy-1-naphthalenyl)azo]- 3-[(2-hydroxy-3-nitro-5...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Chromate (5-), bis - 3- -2... New Uses for Specific Chemical Substances § 721.5284 Chromate (5-), bis - 3- -2- naphthalenesulfonato... chemical substance identified as a Chromate (5-), bis - 3- -2- naphthalenesulfonato(4-)]-, pentasodium...

  11. 40 CFR 721.5284 - Chromate (5-), bis[4-hydroxy-7-[(2-hydroxy-1-naphthalenyl)azo]- 3-[(2-hydroxy-3-nitro-5...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chromate (5-), bis - 3- -2... New Uses for Specific Chemical Substances § 721.5284 Chromate (5-), bis - 3- -2- naphthalenesulfonato... chemical substance identified as a Chromate (5-), bis - 3- -2- naphthalenesulfonato(4-)]-, pentasodium...

  12. 40 CFR 721.5284 - Chromate (5-), bis[4-hydroxy-7-[(2-hydroxy-1-naphthalenyl)azo]- 3-[(2-hydroxy-3-nitro-5...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Chromate (5-), bis - 3- -2... New Uses for Specific Chemical Substances § 721.5284 Chromate (5-), bis - 3- -2- naphthalenesulfonato... chemical substance identified as a Chromate (5-), bis - 3- -2- naphthalenesulfonato(4-)]-, pentasodium...

  13. 40 CFR 721.5284 - Chromate (5-), bis[4-hydroxy-7-[(2-hydroxy-1-naphthalenyl)azo]- 3-[(2-hydroxy-3-nitro-5...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Chromate (5-), bis - 3- -2... New Uses for Specific Chemical Substances § 721.5284 Chromate (5-), bis - 3- -2- naphthalenesulfonato... chemical substance identified as a Chromate (5-), bis - 3- -2- naphthalenesulfonato(4-)]-, pentasodium...

  14. 40 CFR 721.5284 - Chromate (5-), bis[4-hydroxy-7-[(2-hydroxy-1-naphthalenyl)azo]- 3-[(2-hydroxy-3-nitro-5...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Chromate (5-), bis - 3- -2... New Uses for Specific Chemical Substances § 721.5284 Chromate (5-), bis - 3- -2- naphthalenesulfonato... chemical substance identified as a Chromate (5-), bis - 3- -2- naphthalenesulfonato(4-)]-, pentasodium...

  15. 5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)- 1,2-isoxazoline as a useful rice herbicide.

    PubMed

    Hwang, In Taek; Kim, Hyoung Rae; Jeon, Dong Ju; Hong, Kyung Sik; Song, Jong Hwan; Cho, Kwang Yun

    2005-11-01

    5-(2,6-difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline derivative was synthesized, and its herbicidal activity was assessed under glasshouse and flooded paddy conditions. 5-(2,6-Difluorobenzyl)oxymethyl-5-methyl-3-(3-methylthiophen-2-yl)-1,2-isoxazoline demonstrated good rice selectivity and potent herbicidal activity against annual weeds at 125 g of a.i. ha(-1) under greenhouse conditions. Soil application of this compound showed complete control of barnyard-grass to the fourth leaf stage at 250 g of a.i. ha(-1). Field trials indicated that this compound controlled annual weeds rapidly with a good tolerance on transplanted rice seedlings by post-emergence and soil application. This compound showed a low mammalian and environmental toxicity in various toxicological tests. PMID:16248565

  16. The synthesis of protected 5'-amino-2',5'-dideoxyribonucleoside-3'-O-phosphoramidites; applications of 5'-amino-oligodeoxyribonucleotides.

    PubMed Central

    Sproat, B S; Beijer, B; Rider, P

    1987-01-01

    Synthetic routes to the four appropriately protected 5'-amino-2',5'-dideoxyribonucleoside-3'-O-(2-cyanoethyl N,N-diisopropylphosphoramidites) have been developed. The structures of all intermediates were confirmed by 13C n.m.r. spectroscopy. These building blocks have been used to prepare 5'-amino-oligodeoxyribonucleotides, which can be coupled to a wide variety of compounds, in particular metal cluster derivatives, but also fluorophores and biotin derivatives, thus generating a variety of very useful probes. Brief mention is made of a tetrairidium cluster derivative of 5'-amino-d[CCGATATCGG], which has been cocrystallised with EcoRV, and will be used for electron microscopy studies. PMID:3627984

  17. Intracellular localization of human Ins(1,3,4,5,6)P5 2-kinase

    PubMed Central

    Brehm, Maria A.; Schenk, Tobias M. H.; Zhou, Xuefei; Fanick, Werner; Lin, Hongying; Windhorst, Sabine; Nalaskowski, Marcus M.; Kobras, Mario; Shears, Stephen B.; Mayr, Georg W.

    2007-01-01

    InsP6 is an intracellular signal with several proposed functions that is synthesized by IP5K [Ins(1,3,4,5,6)P5 2-kinase]. In the present study, we overexpressed EGFP (enhanced green fluorescent protein)–IP5K fusion proteins in NRK (normal rat kidney), COS7 and H1299 cells. The results indicate that there is spatial microheterogeneity in the intracellular localization of IP5K that could also be confirmed for the endogenous enzyme. This may facilitate changes in InsP6 levels at its sites of action. For example, overexpressed IP5K showed a structured organization within the nucleus. The kinase was preferentially localized in euchromatin and nucleoli, and co-localized with mRNA. In the cytoplasm, the overexpressed IP5K showed locally high concentrations in discrete foci. The latter were attributed to stress granules by using mRNA, PABP [poly(A)-binding protein] and TIAR (TIA-1-related protein) as markers. The incidence of stress granules, in which IP5K remained highly concentrated, was further increased by puromycin treatment. Using FRAP (fluorescence recovery after photobleaching) we established that IP5K was actively transported into the nucleus. By site-directed mutagenesis we identified a nuclear import signal and a peptide segment mediating the nuclear export of IP5K. PMID:17705785

  18. 5f3 --> 5f 26d1 absorption spectrum analysis of U3+-SrCl2.

    PubMed

    Karbowiak, Mirosław

    2005-04-28

    The 5f3--> 5f26d1 absorption spectra of the U3+ ions incorporated in SrCl2 single crystals were recorded at 4.2 K in the 15,000-50,000 cm(-1) spectral range. From an analysis of the vibronic structure, 32 zero-phonon lines corresponding to transitions from the 4I9/2 ground multiplet of the 5f3 configuration to the 5f26d(eg)1 excited levels were assigned. A theoretical model proposed by Reid et al. (Reid, H. F.; van Pieterson, L.; Wegh, R. T.; Meijerink, A. Phys. Rev. B 2000, 62, 14744) that extends the established model for energy-level calculations of nf N states has been applied for analysis of the spectrum. The Fk(ff) (k = 2, 4), zeta(5f)(ff), B0(4)(ff), B0(6)(ff), Fk(fd) (k = 2, 4), and Gj(fd) (j = 1, 3) Hamiltonian parameters were determined by a least-squares fitting of the calculated energies to the experimental data. A good overall agreement between the calculated and experimentally observed energy levels has been achieved, with the root-mean-square (rms) deviation equal to 95 cm(-1) for 32 fitted levels and 9 varied parameters. Adjusted values of Fk(ff) and zeta(5f)(ff) parameters for the 5f2 core electrons are closer to the values characteristic of the 5f2 (U4+) configuration than to those of the 5f3 (U3+) configuration. For the U3+ ion, the f-d Coulomb interaction parameters are significantly more reduced from the values calculated using Cowan's computer code than they are for lanthanide ions. Moreover, because of weaker f-d Coulomb interactions for the U3+ ion than for the isoelectronic Nd3+ lanthanide ion, the very simple model assuming the coupling of crystal-field levels of the 6d1 electron with the lattice and the multiplet structure of the 5f2 configuration may be employed for the qualitative description of the general structure of the U3+ ion f-d spectrum. PMID:16839023

  19. Synthesis of Substituted 2,3,5,6-tetraarylbenzo(1,2-b:5,4-b')difurans

    NASA Technical Reports Server (NTRS)

    Abdul-Aziz, Mahmoud; Auping, Judith V.; Meador, Michael A.

    1995-01-01

    A series of substituted 2,3,5,6-tetraarylbenzo(l,2-b:5,4-b')difurans 1 was synthesized. This synthesis is based upon the photocyclization of 2,5-dibenzoylresorcinol dibenzyl ethers to the corresponding tetrahydrobenzo(1,2-b:5,4-b')difurans. Treatment of the photoproducts with methanesulfonyl chloride in pyridine afforded 1 in overall yields ranging from 30-72%. A number of these compounds have high fluorescence quantum yields (of phi(sub f) = 0.76-0.90), and their fluorescence spectra exhibit large solvatochromic shifts. These compounds may be suitable for use as fluorescent probes.

  20. 2, 3-Bis(5-alkyl-2-thiono-1, 3, 5-thiadiazin-3-yl) propionic acid: one-pot domino synthesis and antimicrobial activity.

    PubMed

    El Bialy, Serry A A; Abdelal, Ali M; El-Shorbagi, Abdel-Nasser; Kheira, Samy M M

    2005-01-01

    In a search for promising antibacterial and antifungal compounds, two new series of 2, 3-bis(5-alkyl-2-thiono-1, 3, 5-thiadiazin-3-yl)propionic acid 1 and their corresponding N, N-dimethylpropionamide 6 have been synthesized. The reaction of 2, 3-diaminopropionate 3, carbon disulfide, formaldehyde, and the appropriate alkyl amines furnished the title compound 1. N, N-dimethylpropionamides 6 were obtained by the reaction of 1 with dimethyl amine in the presence of POCl(3). The newly prepared compounds were screened in vitro against certain strains of Gram-positive and Gram-negative bacteria and compared with nalidixic acid and ciprofloxacin. Moreover, the title compounds were tested for their antifungal activity in vitro against Candida albicans, phytopathogenic, Penicillum expansum and Trichoderma hazianum, and aflatoxin-producing Aspergillus flavus. These compounds exhibit varied activity against the tested pathogenic bacteria and remarkable inhibitory effects on growth or sporulation of some of the tested fungal species. PMID:15674803

  1. Teachers Teaching Teachers (T3)[TM]. Volume 5, Number 2

    ERIC Educational Resources Information Center

    Crow, Tracy, Ed.

    2009-01-01

    "Teachers Teaching Teachers" ("T3") focuses on coaches' roles in the professional development of teachers. Each issue also explores the challenges and rewards that teacher leaders encounter. This issue includes: (1) Sharpening Skills for Our Century (Valerie von Frank); (2) Lessons from a Coach: First, I Assess How Teachers Learn (Julie…

  2. Synthesis crystal structure and ionic conductivity of Ca 0.5Bi 3V 2O 10 and Sr 0.5Bi 3V 2O 10

    NASA Astrophysics Data System (ADS)

    Porob, Digamber G.; Guru Row, T. N.

    2004-12-01

    Two new compounds Ca 0.5Bi 3V 2O 10 and Sr 0.5Bi 3V 2O 10 have been synthesized in the ternary system: MO-Bi 2O 3-V 2O 5 system ( M=M 2+). The crystal structure of Sr 0.5Bi 3V 2O 10 has been determined from single crystal X-ray diffraction data, space group P1¯ and Z=2, with cell parameters a=7.1453(3) Å, b=7.8921(3) Å, c=9.3297(3) Å, α=106.444(2)°, β=94.088(2)°, γ=112.445(2)°, V=456.72(4) Å 3. Ca 0.5Bi 3V 2O 10 is isostructural with Sr 0.5Bi 3V 2O 10, with, a=7.0810(2) Å, b=7.8447(2) Å, c=9.3607(2) Å, α=106.202(1)°, β=94.572(1)°, γ=112.659(1)°, V=450.38(2) Å 3 and its structure has been refined by Rietveld method using powder X-ray data. The crystal structure consists of infinite chains of (Bi 2O 2) along c-axis formed by linkage of BiO 8 and BiO 6 polyhedra interconnected by MO 8 polyhedra forming 2D layers in ac plane. The vanadate tetrahedra are sandwiched between these layers. Conductivity measurements give a maximum conductivity value of 4.54×10 -5 and 3.63×10 -5 S cm -1 for Ca 0.5Bi 3V 2O 10 and Sr 0.5Bi 3V 2O 10, respectively at 725 °C.

  3. 75 FR 23574 - Airworthiness Directives; CFM International, S.A. CFM56-5B1/P, -5B2/P, -5B3/P, -5B3/P1, -5B4/P...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-04

    ... Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) Will not have a significant..., S.A. CFM56-5B1/P, - 5B2/P, -5B3/P, -5B3/P1, -5B4/P, -5B5/P, -5B6/P, -5B7/P, -5B8/P, -5B9/P, -5B1/2P... INFORMATION: The FAA proposed to amend 14 CFR part 39 by superseding AD 2009-01-01, Amendment......

  4. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6-......

  5. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6-......

  6. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6-......

  7. Photoluminescence properties of a novel red phosphor Sr3Ga2O5Cl2:Eu3+

    NASA Astrophysics Data System (ADS)

    Wang, Zhonghua; Hu, Yihua; Zhang, Shaoan; Lin, Jun

    2016-02-01

    Eu3+-doped Sr3Ga2O5Cl2 phosphors were synthesized successfully via a two-step solid-state reaction method. Phase purity and morphology of the phosphor were confirmed by XRD and SEM techniques. In the excitation spectra of Sr3Ga2O5Cl2:Eu3+ phosphor, the broad excitation band centering at 310 nm is due to the combination of charge transfer from Eu3+→O2- and host absorption. And it matches well the emission wavelength from UV LEDs. Sr3Ga2O5Cl2:Eu3+ phosphors show a bright orange-red luminescence under excitation with 301 nm. However, concentration quenching of Eu3+ in Sr3Ga2O5Cl2:Eu3+ occurs at a low content of 0.07 in this work. The quenching mechanism of Sr3Ga2O5Cl2:Eu3+ was discussed in detail on the basis of the experimental results.

  8. Mixed Valent Gold Oxides: Syntheses, Structures, and Properties of Rb 5Au 3O 2, Rb 7Au 5O 2, and Cs 7Au 5O 2

    NASA Astrophysics Data System (ADS)

    Mudring, Anja-Verena; Nuss, Jürgen; Wedig, Ulrich; Jansen, Martin

    2000-11-01

    The title compounds Rb5Au3O2, Rb7Au5O2, and Cs7Au5O2 are the first examples of mixed valent phases containing gold in the oxidation states +1 and -1. Their crystal structures (Rb5Au3O2, Pbam, a=736.4(1) pm, b=1430.8(2) pm, c=567.9(1) pm, Z=2, R(F)=0.053, 647 reflections; Rb7Au5O2, Immm, a=567.1(2) pm, b=930.1(1) pm, C=1659.4(3) pm, Z=2, R(F)=0.066, 409 reflections; Cs7Au5O2, Immm, a=599.4(1) pm, b=960.6(3) pm, c=1720.8(12) pm, Z=2, R(F)=0.039, 386 reflections) are characterized by the combination of distinctive structural features of gold(I) oxides and aurides: for Au(+1) a typical linear coordination by oxygen is found and the surroundings of Au(-1) bear a close resemblance to the binary 1:1 aurides. In consequence the overall structures of Rb5Au3O2 and M7Au5O2 can be described as intergrowths of M3AuO2 and MAu (M=Rb, Cs), constituting members of a homologous series [MAu]n[M3AuO2] with n=2 and 4, respectively. The crystal chemical evidence for the valence states assumed, also confirmed by Mößbauer spectroscopy, is supported by various band structure calculations (Hartee-Fock and density functional) clearly indicating the coexistence of two different oxidation states. The compounds have been synthesized by reacting binary aurides MAu and alkali monoxides M2O (M=Rb, Cs) with elemental gold in the required stochiometric amounts. Hereby, a further astonishing parallel to the chemistry of halogens is revealed. Like these, gold disproportionates upon interaction with bases.

  9. The synthesis of protected 5'-mercapto-2',5'-dideoxyribonucleoside-3'-O-phosphoramidites; uses of 5'-mercapto-oligodeoxyribonucleotides.

    PubMed Central

    Sproat, B S; Beijer, B; Rider, P; Neuner, P

    1987-01-01

    The syntheses of the four novel, base protected 5'-(S-triphenylmethyl)mercapto-2',5'-dideoxyribonucleoside-3 '-O-(2-cyanoethyl N,N-diisopropylphosphoramidites) are described. These compounds have been used to prepare 5'-(S-triphenylmethyl) mercapto-oligodeoxyribonucleotides, which are readily purified by reversed phase h.p.l.c., owing to the highly lipophilic trityl group. After cleavage of the S-trityl group by silver or mercuric ions, the free thiol moiety can be coupled to a wide variety of reagents, generating very useful probes. Fluorescent labelled 5'-mercapto-oligodeoxyribonucleotides are being used for automated DNA sequencing without radioactivity, and heavy metal labelled 5'-mercapto-oligonucleotides will be used in X-ray crystallography. PMID:3601657

  10. Molecular weight dependent charge carrier mobility in poly(3,3' '-dioctyl-2,2':5',2' '-terthiophene).

    PubMed

    Verilhac, Jean-Marie; Pokrop, Rafal; LeBlevennec, Gilles; Kulszewicz-Bajer, Irena; Buga, Katarzyna; Zagorska, Malgorzata; Sadki, Said; Pron, Adam

    2006-07-13

    Poly(3,3' '-dioctyl-2,2':5',2' '-terthiophene), a polymer recently used for the fabrication of organic field effect transistors, has been fractionated into five fractions distinctly differing in their molecular weights (Mn), with the goal of determining the influence of the degree of polymerization (DPn) on its principal physicochemical parameters. It has been demonstrated that within the Mn range studied (from 1.5 kDa to 10.5 kDa by SEC), corresponding to DPn from 10 to 38, the polymer band gap steadily decreases with growing molecular weight, which is clearly manifested by an increasing bathochromic shift of the band originating from the pi-pi* transition. The same trend is observed for the HOMO level, determined from the onset of the p-doping in cyclic voltammetry, which shifts from -5.10 eV to -4.90 eV for the lowest and the highest molecular weight fractions, respectively. The most pronounced influence of DPn has been found for the charge carriers' mobility-one of the most important parameters of field effect transistors (FETs) fabricated from this polymer. A fourfold increase in DPn results in an increase of the carriers' mobility by more than 3 orders of magnitude. Comparison of these results with those obtained for fractionated regioregular poly(3-hexylthiophene) shows a strikingly similar behavior of both polymers with respect to the molecular weight. PMID:16821847

  11. Nd3+ sensitized upconversion luminescence of Nd3+/Pr3+ codoped KPb2Cl5 low phonon crystal

    NASA Astrophysics Data System (ADS)

    Balda, R.; Al-Saleh, M.; Arriandiaga, M. A.; Garcia-Revilla, S.; Fernández, J.

    2011-03-01

    In this work, we report the upconversion emission from Pr3+ and Nd3+ ions in potassium lead chloride crystal KPb2Cl5after excitation in the 4F5/2,3/2 levels of Nd3+ ions. We have observed violet, blue, green, orange, and red emissions at room temperature. Blue emission from Pr3+ ions is induced by near infrared laser excitation of Nd3+ through energy transfer from Nd3+ to Pr3+ ions. The mechanisms leading to the visible emissions have been investigated by studying the dependence of the upconversion luminescence on the excitation wavelength and intensity of the IR pump light.

  12. Photoionization from the 5p {sup 2}P{sub 3/2} state of rubidium

    SciTech Connect

    Nadeem, Ali; Haq, S. U.

    2011-06-15

    We report two-step photoionization studies from the 5p {sup 2}P{sub 3/2} excited state of rubidium using two dye lasers simultaneously pumped by a common Nd:YAG laser in conjunction with a thermionic diode ion detector. The photoionization cross section at the first ionization threshold is measured as 18.8 {+-} 3 Mb and at excess energies of 0.013, 0.106, 0.229, and 0.329 eV is measured as 15, 13.6, 12.6, and 12.5 Mb, respectively. The measured value of the photoionization cross section at the threshold is used to calibrate the oscillator strengths of the 5p {sup 2}P{sub 3/2}{yields}nd {sup 2}D{sub 5/2} (22 {<=}n{<=} 52) Rydberg transitions.

  13. Optical pump-probe processes in Nd3+-doped KPb2Br5, RbPb2Br5, and KPb2Cl5

    NASA Astrophysics Data System (ADS)

    Rademaker, Katja; Payne, Stephen A.; Huber, Günter; Isaenko, Ludmila I.; Osiac, Eugen

    2005-12-01

    Recently, laser activity has been achieved in the low-phonon-energy, moisture-resistant bromide host crystals: neodymium-doped potassium lead bromide (Nd3+:KPb2Br5) and rubidium lead bromide (Nd3+:RbPb2Br5). Laser activity at 1.07 μm was observed for both crystalline materials. Laser operation at the new wavelengths of 1.18 and 0.97 μm resulting from the 4F5/2+2H9/2-->4IJ transitions (J=13/2 and 11/2) in Nd:RbPb2Br5 was achieved for the first time in a solid-state laser material. We present cw pump-probe spectra and discuss excited-state absorption and reabsorption processes due to the long-lived lower laser levels, as well as possible depopulation mechanisms feasible for more efficient laser operation in these crystals. The bromides are compared with potassium lead chloride (Nd3+:KPb2Cl5).

  14. Natural 4-hydroxy-2,5-dimethyl-3(2H)-furanone (Furaneol®).

    PubMed

    Schwab, Wilfried

    2013-01-01

    4-Hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF, furaneol®) and its methyl ether 2,5-dimethyl-4-methoxy-3(2H)-furanone (DMMF) are import aroma chemicals and are considered key flavor compounds in many fruit. Due to their attractive sensory properties they are highly appreciated by the food industry. In fruits 2,5-dimethyl-3(2H)-furanones are synthesized by a series of enzymatic steps whereas HDMF is also a product of the Maillard reaction. Numerous methods for the synthetic preparation of these compounds have been published and are applied by industry, but for the development of a biotechnological process the knowledge and availability of biosynthetic enzymes are required. During the last years substantial progress has been made in the elucidation of the biological pathway leading to HDMF and DMMF. This review summarizes the latest advances in this field. PMID:23765232

  15. Cooperative intramolecular hydrogen bonds in the structure of 5,5'-dibromo-3-diethylaminomethyl-2,2'-biphenol

    NASA Astrophysics Data System (ADS)

    Bartoszak-Adamska, E.; Wojciechowski, G.; Jaskólski, M.; Brzezinski, B.

    2000-07-01

    Crystals of 5,5'-dibromo-3-diethylaminomethyl-2,2'-biphenol were examined using X-ray diffraction and FT-IR spectroscopy. The space group is P2 1/ n with a=8.617(2), b=16.356(3), c=12.854(3) Å, β=108.03(3)° and Z=4. The molecule exists in the crystal in zwitterionic state as a result of proton transfer from a hydroxyl group to the adjacent amino group. These two groups, together with the hydroxyl group of the second phenol moiety are involved in a system of cooperative intramolecular hydrogen bonds, O(2)H⋯O(1) -H +N(1). The O⋯O and O⋯N distances are 2.476(5) and 2.584(5) Å, the O-H and H-N distances 0.89 and 1.04 Å, and the O-H⋯O and O⋯H-N + angles 163 and 141°, respectively. The IR spectra of the crystals are consistent with the results of the X-ray analysis. Instead of a continuous absorption, only broad bands are found indicating very low proton polarizability in the two types of intramolecular hydrogen bonds.

  16. Optical pump-probe processes in Nd 3+ doped KPb2Br5, RbPb2Br5, and KPb2CI5

    SciTech Connect

    Rademaker, K; Huber, G; Payne, S A; Osiac, E; Isaenko, L I

    2004-10-28

    Recently, laser activity has been achieved in the low phonon energy, moisture-resistant bromide host crystals, neodymium-doped potassium lead bromide (Nd{sup 3+}:KPb{sub 2}Br{sub 5}) and rubidium lead bromide (Nd{sup 3+}:RbPb{sub 2}Br{sub 5}). Laser activity at 1.07 {micro}m was observed for both crystalline materials. Laser operation at the new wavelengths 1.18 {micro}m and 0.97 {micro}m resulting from the {sup 4}F{sub 5/2}+{sup 2}H{sub 9/2} {yields} {sup 4}I{sub J} transitions (J=13/2 and 11/2) in Nd:RPB was achieved for the first time in a solid state laser material. In this paper we present cw pump-probe spectra in order to discuss excited state absorption, reabsorption processes due to the long lived lower laser levels as well as possible depopulation mechanisms feasible for more efficient laser operation in these crystals. The bromides will be compared with potassium lead chloride (Nd{sup 3+}:KPb{sub 2}Cl{sub 5}).

  17. Use of 2,3,5-F3Y-β2 and 3-NH2Y-α2 to study PCET in E. coli Ribonucleotide Reductase

    PubMed Central

    Seyedsayamdost, Mohammad R.; Yee, Cyril S.; Stubbe, JoAnne

    2011-01-01

    E. coli ribonucleotide reductase is an α2β2 complex that catalyzes the conversion of nucleoside 5′-diphosphates (NDPs) to deoxynucleotides (dNDPs). The active site for NDP reduction resides in α2, and the essential diferric-tyrosyl radical (Y122•) cofactor that initiates radical transfer to the active site cysteine in α2 (C439), 35 Å removed, is in β2. The oxidation is proposed to involve a hopping mechanism through aromatic amino acids (Y122→W48→Y356 in β2 to Y731→Y730→C439 in α2) and reversible proton coupled electron transfer (PCET). Recently 2,3,5-F3Y (F3Y) was site-specifically incorporated in place of Y356 in β2, and 3-NH2Y (NH2Y) in place of Y731 and Y730 in α2. A pH rate profile with F3Y356-β2 suggested that as the pH is elevated, the rate-determining step of RNR can be altered from a conformational change to PCET and that the altered driving force for F3Y oxidation, by residues adjacent to it in the pathway, is responsible for this change. Studies with NH2Y731(730)-α22/CDP/ATP resulted in detection of NH2Y radical (NH2Y•) intermediates capable of dNDP formation. In this study, the reaction of F3Y356-β22/CDP/ATP has been examined by stopped flow (SF) absorption and rapid freeze quench EPR spectroscopy and has failed to reveal any radical intermediates. F3Y356-β2/CDP/ATP has also been examined with NH2Y731-α2 (or NH2Y730-α2) by stopped-flow kinetics from pH 6.5–9.2 and revealed rate constants for NH2Y• formation that support a change in rate limiting step at elevated pH. The results together with kinetic simulations provide a guide for future studies to detect radical intermediates in the pathway. PMID:21182280

  18. (2,2-Bipyridyl)bis(eta5-1,2,3,4,5-pentamethylcyclopentadienyl)Strontium(II)

    SciTech Connect

    Kazhdan, Daniel; Kazhdan, Daniel; Hu, Yung-Jin; Kokai, Akos; Levi, Zerubba; Rozenel, Sergio

    2008-07-03

    In the title compound, the Sr-N distances are 2.624 (3) and 2.676 (3) Angstroms. The Sr-centroid distances are 2.571 and 2.561 Angstroms. The N-C-C-N torsion angle in the bipyridine ligand is 2.2 (4){sup o}. Interestingly, the bipyridine ligand is tilted. The angle between the plane defined by Sr1, N1 and N2 and the plane defined by the 12 atoms of the bipyridine ligand is 10.7{sup o}.

  19. Discovery of 5-(5,5-Dimethylbutenolide-3-ethylidene)-2-amino-imidazolinone Derivatives as Fungicidal Agents.

    PubMed

    Tang, Bo; Yang, Mingyan; Zhao, Yu; Kong, Lingqing; Wang, Weiwei; Wang, Mingan

    2015-01-01

    The novel fungicidal agents 5-(5,5-dimethylbutenolide-3-ethylidene)-2-amino-imidazolinone derivatives, were designed and synthesized in moderate to excellent yields in four steps by αa-hydroxyketone and diketene as raw materials and characterized by HR-ESI-MS and 1H-NMR. The preliminary bioassay showed that some of these compounds, such as 4a, 4e and 5g exhibit 94.9%, 92.8% and 81.4% inhibition rates against Sclerotinia scleotiorum at the concentration of 50 µg/mL, respectively. The EC50 values of compounds 4e and 4i were 4.14 and 3.27 µM against Alternaria Solani, and 5g had EC50 value of 3.23 µM against S. scleotiorum. Compounds 4d and 4g displayed 98.0% and 97.8% control of spore germination against Botrytis cinerea at the concentration of 100 µg/mL, respectively. PMID:26225953

  20. Superconductivity versus structural phase transition in the closely related Bi2Rh3.5S2 and Bi2Rh3S2

    DOE PAGESBeta

    Kaluarachchi, Udhara S.; Xie, Weiwei; Lin, Qisheng; Taufour, Valentin; Bud'ko, Sergey L.; Miller, Gordon J.; Canfield, Paul C.

    2015-05-19

    Single crystals of Bi2Rh3S2 and Bi2Rh3.5S2 were synthesized by solution growth, and the crystal structures and thermodynamic and transport properties of both compounds were studied. In the case of Bi2Rh3S2, a structural first-order transition at around 165 K is identified by single-crystal diffraction experiments, with clear signatures visible in resistivity, magnetization, and specific heat data. No superconducting transition for Bi2Rh3S2 was observed down to 0.5 K. In contrast, no structural phase transition at high temperature was observed for Bi2Rh3.5S2; however, bulk superconductivity with a critical temperature, Tc ≈ 1.7 K, was observed. The Sommerfeld coefficient γ and the Debye temperaturemore » (ΘD) were found to be 9.41 mJ mol–1K–2 and 209 K, respectively, for Bi2Rh3S2, and 22 mJ mol–1K–2 and 196 K, respectively, for Bi2Rh3.5S2. As a result, the study of the specific heat in the superconducting state of Bi2Rh3.5S2 suggests that Bi2Rh3.5S2 is a weakly coupled, BCS superconductor.« less

  1. Superconductivity versus structural phase transition in the closely related Bi2Rh3.5S2 and Bi2Rh3S2

    NASA Astrophysics Data System (ADS)

    Kaluarachchi, Udhara S.; Xie, Weiwei; Lin, Qisheng; Taufour, Valentin; Bud'ko, Sergey L.; Miller, Gordon J.; Canfield, Paul C.

    2015-05-01

    Single crystals of Bi2Rh3S2 and Bi2Rh3.5S2 were synthesized by solution growth, and the crystal structures and thermodynamic and transport properties of both compounds were studied. In the case of Bi2Rh3S2 , a structural first-order transition at around 165 K is identified by single-crystal diffraction experiments, with clear signatures visible in resistivity, magnetization, and specific heat data. No superconducting transition for Bi2Rh3S2 was observed down to 0.5 K. In contrast, no structural phase transition at high temperature was observed for Bi2Rh3.5S2 ; however, bulk superconductivity with a critical temperature, Tc≈1.7 K, was observed. The Sommerfeld coefficient γ and the Debye temperature (ΘD ) were found to be 9.41 mJ mol-1K-2 and 209 K, respectively, for Bi2Rh3S2 , and 22 mJ mol-1K-2 and 196 K, respectively, for Bi2Rh3.5S2 . Study of the specific heat in the superconducting state of Bi2Rh3.5S2 suggests that Bi2Rh3.5S2 is a weakly coupled, BCS superconductor.

  2. Synthesis, spectroscopic characterization, antimicrobial activity and crystal structure of [Ag2(C10H10N3O3S)2(C5H5N)3

    NASA Astrophysics Data System (ADS)

    Tailor, Sanjay M.; Patel, Urmila H.

    2015-05-01

    Silver complex of 4-Amino-N-(5-methyl-1,2-oxazol-3-yl)benzenesulfonamide (sulfamethoxazole) (SMX) has been synthesized and characterized by elemental analysis, infrared, UV and NMR spectroscopy. The title compound, [Ag2(C10H10N3O3S)2(C5H5N)3] crystallizes in the orthorhombic space group Pna21 with lattice parameters a = 17.9527(5), b = 8.6529(3), c = 25.1621(7) Å and Z = 4. The structure is solved by direct method and refined to a final R = 0.0567 for 6732 reflections with I ⩾ 2σ(I). The results of IR, 1H NMR and 13C NMR spectral data suggest the binding of silver atom to the sulfonamide ligand which is in agreement with the crystal structure determination. X-ray analysis revealed that in the title compound, one silver atom is surrounded by three N atoms and one Ag atom leading to a distorted tetrahedral geometry and another silver atom is surrounded by four N atoms and one Ag atom leading to a slightly distorted square pyramid geometry with Ag⋯Ag separation distance of 3.026 Å. The dihedral angle between phenyl and isoxazole ring is 85.7(4)°. In the crystal structure, the molecules are linked via Nsbnd H⋯O, Csbnd H⋯O intermolecular and Csbnd H⋯O intramolecular interactions. Silver complex of sulfamethoxazole has been studied by electrical and thermal analysis. Silver sulfamethoxazole presents different antibacterial behavior against Escherichia coli and Staphylococcus aureus strains.

  3. Fluorination of 1,2,3,4- and 1,2,3,5-tetrahalobenzenes with potassium fluoride in dimethyl sulfone

    USGS Publications Warehouse

    Finger, G.C.; Dickerson, D.R.; Shiley, R.H.

    1972-01-01

    1,2,3,4-Tetrachlorobenzene, 1,2,3,5-tetrachlorobenzene, 2,4,6-trichlorofluorobenzene, and 2,6-dichloro-1,4-difluorobenzene were fluorinated with potassium fluoride and potassium fluoride-cesium fluoride mixtures in dimethyl sulfone. By varying the concentration, temperature and reaction time, the degree of fluorination could be controlled to some extent. The optimum conditions for producing mono-, di- and tri-fluoro-substituted chlorobenzenes and trace amounts of tetrafluorobenzene from the corresponding tetrachlorobenzenes are given. 1,2,3,5-Tetrafluorobenzene was obtained in 44.8% yield from 2,6-dichloro-1,4-difluorobenzene. 1,2,3,4-Tetrafluorobenzene was obtained in only trace amounts from 1,2,3,4-tetrachlorobenzene. A total of 24 new chlorofluorobenzenes and intermediates are described. Fluorination with potassium fluoride and certain other metal fluorides was also investigated. ?? 1972.

  4. Oligoribonucleotides containing 2',5'-phosphodiester linkages exhibit binding selectivity for 3',5'-RNA over 3',5'-ssDNA.

    PubMed Central

    Giannaris, P A; Damha, M J

    1993-01-01

    Oligoribonucleotides containing 2',5'-phosphodiester linkages have been synthesized on a solid support by the 'silyl-phosphoramidite' method. The stability of complexes formed between these oligonucleotides and complementary 3',5'-RNA strands have been studied using oligoadenylates and a variety of oligonucleotides of mixed base sequences including phosphorothioate backbones. In many cases, particularly for 2',5'-linked adenylates, the UV melting profiles are quite sharp and exhibit large hyperchromic changes. Substituting a few 3',5'-linkages with the 2',5'-linkage within an oligomer lowers the Tm of the complex and the degree of destabilization depends on the neighboring residues and neighboring linkages. The 2',5'-linked oligoribonucleotides prepared in this study exhibited remarkable selectivity for complementary single stranded RNA over DNA. For example, in 0.01 M phosphate buffer--0.10 M NaCl (pH 7.0), no association was observed between 2',5'-r(CCC UCU CCC UUC U) and its Watson-Crick DNA complement 3',5'-d(AGAAGGGAGAGGG). However, 2',5'-r(CCC UCU CCC UUC U) with its RNA complement 3',5'-r(AGAAGGGAGAGGG) forms a duplex which melts at 40 degrees C. The decamer 2',5'-r(Ap)9A forms a complex with both poly dT and poly rU but the complex [2',5'-r(Ap)9A]:[poly dT] is unstable (Tm, -1 degree C) and is seen only at high salt concentrations. In view of their unnatural character and remarkable selectivity for single stranded RNA, 2',5'-oligo-RNAs and their derivatives may find use as selective inhibitors of viral mRNA translation, and as affinity ligands for the purification of cellular RNA. Images PMID:7694233

  5. Electron attachment to SF5X compounds: SF5C6H5, SF5C2H3, S2F10, and SF5Br, 300-550 K.

    PubMed

    Miller, Thomas M; Viggiano, A A; Dolbier, William R; Sergeeva, Tatiana A; Friedman, Jeffrey F

    2007-02-15

    Rate constants and ion product channels have been measured for electron attachment to four SF5 compounds, SF5C6H5, SF5C2H3, S2F10, and SF5Br, and these data are compared to earlier results for SF6, SF5Cl, and SF5CF3. The present rate constants range over a factor of 600 in magnitude. Rate constants measured in this work at 300 K are 9.9+/-3.0x10(-8) (SF5C6H5), 7.3+/-1.8x10(-9) (SF5C2H3), 6.5+/-2.5x10(-10) (S2F10), and 3.8+/-2.0x10(-10) (SF5Br), all in cm3 s-1 units. SF5- was the sole ionic product observed for 300-550 K, though in the case of S2F10 it cannot be ascertained whether the minor SF4- and SF6- products observed in the mass spectra are due to attachment to S2F10 or to impurities. G3(MP2) electronic structure calculations (G2 for SF5Br) have been carried out for the neutrals and anions of these species, primarily to determine electron affinities and the energetics of possible attachment reaction channels. Electron affinities were calculated to be 0.88 (SF5C6H5), 0.70 (SF5C2H3), 2.95 (S2F10), and 2.73 eV (SF5Br). An anticorrelation is found for the Arrhenius A-factor with exothermicity for SF5- production for the seven molecules listed above. The Arrhenius activation energy was found to be anticorrelated with the bond strength of the parent ion. PMID:17286358

  6. Reactions of organyl and silyl alanes with 1,3,4,5,6-pentamethyl-2-aminoborazine.

    PubMed

    Fan, Maomin; Duesler, Eileen N; Nöth, Heinrich; Paine, Robert T

    2010-03-15

    The reactions of (Me(3)Si)(3)Al, Me(3)Al, Et(3)Al, and i-Bu(3)Al with 1,3,4,5,6-pentamethyl-2-aminoborazine have been examined. An amine alane adduct (Me(3)Si)(3)Al.NH(2)B(3)(Me)(2)N(3)Me(3) (1) and several elimination products [(Me(3)Si)(2)AlN(H)B(3)(Me)(2)N(3)Me(3)](2) (2), [(Me(3)SiAl)(4)(Me(3)SiN)(3)NH] (3), [Me(2)AlN(H) B(3)(Me)(2)N(3)Me(3)](2) (4), [Et(2)AlN(H) B(3)(Me)(2)N(3)Me(3)](2) (5), and [i-Bu(2)AlN(H) B(3)(Me)(2)N(3)Me(3)](2) (6) have been isolated. Compounds 1, 2, 4-6 have been spectroscopically characterized, and single crystal X-ray diffraction structure determinations have been completed for 1-4 and 6. The molecular chemistry provides insight into the reaction of Me(3)Al and 1,3,5-N-trimethyl-2,4,6-B-triaminoborazine that, upon pyrolysis, produces AlN/BN composite ceramic materials. PMID:20158196

  7. Strong white light in P2O5-Li2O-Yb2O3-Sb2O3 glass doped with Pr3+ion

    NASA Astrophysics Data System (ADS)

    Ming, Chengguo; Han, Yingdong; Song, Feng; Ren, Xiaobin; An, Liqun

    2013-01-01

    P2O5-Li2O-Yb2O3-Sb2O3 glasses doped with Pr3+ ion had been prepared to explore white-light-emitting materials. The photoluminescence spectra of the glasses were measured under 270 nm excitation. The emission color of the glass doped with 2 mol% Pr3+ ion was white to the naked eye, and the CIE coordinates (0.336, 0.319) of the sample were close to the standard equal energy white-light illumination (x=0.333, y=0.333). The present working mechanism of the commercial white-LEDs is that a yellow phosphor is excited by a blue LED chip. The emission characters are restricted by the intensity of the blue light and the thickness of the phosphor. However, the luminescent characters of our materials are not effected by the pumping light. Thus, our materials will be helpful in developing white-light-emitting materials.

  8. Thermally stable compositions including 2,4,8,10-tetranitro-5H-pyrido[3',2':4,5][1,2,3]triazolo[1,2-a]benzotriazo- l-6-ium, inner salt

    DOEpatents

    Hiskey, Michael A.; Huynh, My Hang

    2010-01-26

    An explosive formulation including 2,4,8,10-tetranitro-5H-pyrido[3',2':4,5][1,2,3]triazolo[1,2-a]benzotriazo- l-6-ium, inner salt and a high temperature binder is disclosed together with a process of preparing 2,4,8,10-tetranitro-5H-pyrido[3',2':4,5][1,2,3]triazolo[1,2-a]benzotriazo- l-6-ium, inner salt.

  9. 40 CFR 721.5262 - 2,7-Naphthalenedisulfonic acid, 5-[[4-chloro-6-[substituted] amino]-1,3,5-triazin-2-yl]amino]-4...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...,7-Naphthalenedisulfonic acid, 5- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, trisodium salt...-Naphthalenedisulfonic acid, 5- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, trisodium salt (PMN P-00-0803) is...-naphthalenedisulfonic acid, 5- ethyl]amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, sodium salt (1:3) (PMN......

  10. Energetic derivatives of 5-(5-amino-2H-1,2,3-triazol-4-yl)-1H-tetrazole.

    PubMed

    Izsák, Dániel; Klapötke, Thomas M; Pflüger, Carolin

    2015-10-21

    This study presents the preparation of the novel nitrogen-rich compound 5-(5-amino-2H-1,2,3-triazol-4-yl)-1H-tetrazole (5) from commercially available chemicals in a five step synthesis. The more energetic derivatives with azido (6) and nitro (7) groups, as well as a diazene bridge (8) were also successfully prepared. The energetic compounds were comprehensively characterized by various means, including vibrational (IR, Raman) and multinuclear ((1)H, (13)C, (14)N, (15)N) NMR spectroscopy, mass spectrometry and differential thermal analysis. The sensitivities towards important outer stimuli (impact, friction, electrostatic discharge) were determined according to BAM standards. The enthalpies of formation were calculated on the CBS-4M level of theory, revealing highly endothermic values, and were utilized to calculate the detonation parameters using EPXLO5 (6.02). PMID:26361356

  11. Impedance spectroscopy of V2O5-Bi2O3-BaTiO3 glass-ceramics

    NASA Astrophysics Data System (ADS)

    Al-syadi, Aref M.; Yousef, El Sayed; El-Desoky, M. M.; Al-Assiri, M. S.

    2013-12-01

    The glasses within composition as: (80 - x)V2O5/20Bi2O3/xBaTiO3 with x = 2.5, 5, 7.5 and 10 mol% have been prepared. The glass transition (Tg) increases with increasing BaTiO3 content. Synthesized glasses ceramic containing BaTi4O9, Ba3TiV4O15 nanoparticles of the order of 25-35 nm and 30-46 nm, respectively were estimated using XRD. The dielectric properties over wide ranges of frequencies and temperatures were investigated as a function of BaTiO3 content by impedance spectroscopy measurements. The hopping frequency, ωh, dielectric constant, ɛ', activation energies for the DC conduction, Eσ, the relaxation process, Ec, and stretched exponential parameter β of the glasses samples have been estimated. The, ωh,β, decrease from 51.63 to 0.31 × 106 (s-1), 0.84 to 0.79 with increasing BaTiO3 respectively. Otherwise, the Eσ, increase from 0.279 to 0.306 eV with increasing BaTiO3. The value of dielectric constant equal 9.5·103 for the 2.5BaTiO3/77.5V2O5/20Bi2O3 glasses-ceramic at 330 K for 1 KHz which is ten times larger than that of same glasses composition. Finally the relaxation properties of the investigated glasses are presented in the electric modulus formalism, where the relaxation time and the respective activation energy were determined.

  12. 40 CFR 721.5262 - 2,7-Naphthalenedisulfonic acid, 5-[[4-chloro-6-[substituted] amino]-1,3,5-triazin-2-yl]amino]-4...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...,7-Naphthalenedisulfonic acid, 5- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, trisodium salt... identified generically as 2,7-Naphthalenedisulfonic acid, 5- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 2,7-Naphthalenedisulfonic acid,...

  13. 40 CFR 721.5262 - 2,7-Naphthalenedisulfonic acid, 5-[[4-chloro-6-[substituted] amino]-1,3,5-triazin-2-yl]amino]-4...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...,7-Naphthalenedisulfonic acid, 5- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, trisodium salt... identified generically as 2,7-Naphthalenedisulfonic acid, 5- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 2,7-Naphthalenedisulfonic acid,...

  14. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-ethenediyl)bis - 6- -1,3,5-triazin-2-yl]amino]-, disodium salt, compd. with 2,2â²,2â³-nitrilo-tris (1:2); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...-ethenediyl)bis - 6- -1,3,5-triazin-2-yl]amino]-, disodium salt, compd. with......

  15. 40 CFR 721.9790 - Benzenesulfonic acid, 2,2′-(1,2-ethenediyl)bis[5-[[4-[bis(2-hydroxypropyl) amino]- 6-[(3...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-ethenediyl)bis - 6- -1,3,5-triazin-2-yl]amino]-, disodium salt, compd. with 2,2â²,2â³-nitrilo-tris (1:2); Benzenesulfonic acid, 5- -6- -1,3,5-triazin-2-yl]amino]-2- -6- -1,3,5-triazin-2-yl]amino]-2-sulfophenyl]ethenyl...-ethenediyl)bis - 6- -1,3,5-triazin-2-yl]amino]-, disodium salt, compd. with......

  16. Process for the preparation of halogenated 3,3-dimethyl-5-hexen-2-ones

    SciTech Connect

    Chou, M.S.; Wohltman, K.W.

    1986-07-22

    A process is described for the production of hydroperoxides comprising the steps of: adding an oxygen-containing gas to a feed hydrocarbon selected from the group consisting cumene, ethylbenzene, isobutane and cyclohexane in the presence of a promoter ketone selected from the group consisting of benzophenone, ortho-(NO/sub 2/)(C/sub 6/H/sub 4/)/sub 2/C==O, (meta-(NO/sub 2/)(C/sub 6/H/sub 4/)/sub 2/C==O, (C/sub 6/F/sub 5/)/sub 2/C==O and (C/sub 6/F/sub 3/)/sub 2/C==O which ketone results in a reaction rate to a corresponding hydroperoxide higher than the reaction rate occurring with acetophenone upon hydrocarbon at the same conditions, at a temperature between 100 and 200/sup 0/C to produce a corresponding hydroperoxide product, and recovering the corresponding hydroperoxide product.

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

    NASA Astrophysics Data System (ADS)

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

    2012-06-01

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

  18. Synthesis, structure and magnetic properties of new phosphates K 2Mn 0.5Ti 1.5(PO 4) 3 and K 2Co 0.5Ti 1.5(PO 4) 3 with the langbeinite structure

    NASA Astrophysics Data System (ADS)

    Ogorodnyk, Ivan V.; Zatovsky, Igor V.; Slobodyanik, Nikolay S.; Baumer, Vyacheslav N.; Shishkin, Oleg V.

    2006-11-01

    New complex phosphates of the general formula K 2M0.5Ti 1.5(PO 4) 3 ( M=Mn, Co) have been obtained from the melting mixture of KPO 3, K 4P 2O 7, TiO 2 and CoCO 3· mCo(OH) 2 or Mn(H 2PO 4) 2 by means of a flux technique. The synthesized phosphates have been characterized by the single-crystal X-ray diffraction and the FTIR-spectroscopy. The compounds crystallize in the cubic system with the space group P2 13 and cell parameters a=9.9030(14) Å for K 2Mn 0.5Ti 1.5(PO 4) 3 and a=9.8445(12) Å for K 2Co 0.5Ti 1.5(PO 4) 3. Both phosphates are isostructural with the langbeinite mineral and contain four formula unit K 2M0.5Ti 1.5(PO 4) 3 per unit cell. The structure can be described using [ M2(PO 4) 3] framework composed of two [ MO 6] octahedra interlinked via three [PO 4] tetrahedra. The Curie-Weiss-type behavior is observed in the magnetic susceptibility.

  19. 2,2,4-Trimethyl-7-nitro-2,3-dihydro-1H-1,5-benzodiazepin-5-ium perchlorate

    PubMed Central

    Mehdi, Sayed Hasan; Sulaiman, Othman; Ghalib, Raza Murad; Yeap, Chin Sing; Fun, Hoong-Kun

    2010-01-01

    In the title mol­ecular salt, C12H16N3O2 +·ClO4 −, the nitro group is close to being coplanar with the benzene ring [dihedral angle = 8.1 (3)°]. The seven-membered ring has a maximum deviation of 0.502 (3) Å at the C atom between the dimethyl- and methyl-substituted C atoms. In the crystal, the components are linked into infinite sheets lying parallel to the bc plane by N—H⋯O and C—H⋯O hydrogen bonds. A short O⋯N contact of 2.896 (4) Å occurs within the sheets and a short O⋯O contact of 2.608 (4) Å occurs between the sheets. PMID:21588044

  20. Alkaline hydrolysis of hexahydro-1,3,5-trinitro-1,3,5-triazine: M06-2X investigation.

    PubMed

    Sviatenko, Liudmyla K; Gorb, Leonid; Hill, Frances C; Leszczynska, Danuta; Okovytyy, Sergiy I; Leszczynski, Jerzy

    2015-09-01

    Alkaline hydrolysis mechanism of possible environmental contaminant RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) was investigated computationally at the PCM(Pauling)/M06-2X/6-311++G(d,p) level of theory. Results obtained show that the initial deprotonation of RDX by hydroxide leads to nitrite elimination and formation of a denitrated cyclohexene intermediate. Further nucleophilic attack by hydroxide onto cyclic CN double bond results in ring opening. It was shown that the presence of hydroxide is crucial for this stage of the reaction. The dominant decomposition pathway leading to a ring-opened intermediate was found to be formation of 4-nitro-2,4-diazabutanal. Hydrolytic transformation of its byproduct (methylene nitramine) leads to end products such as formaldehyde and nitrous oxide. Computational results are in a good agreement with experimental data on hydrolysis of RDX, suggesting that 4-nitro-2,4-diazabutanal, nitrite, formaldehyde, and nitrous oxide are main products for early stages of RDX decomposition under alkaline conditions. PMID:25911044

  1. 40 CFR 721.5262 - 2,7-Naphthalenedisulfonic acid, 5-[[4-chloro-6-[substituted] amino]-1,3,5-triazin-2-yl]amino]-4...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, trisodium salt (generic). 721.5262 Section 721.5262...,7-Naphthalenedisulfonic acid, 5- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, trisodium salt... identified generically as 2,7-Naphthalenedisulfonic acid, 5-......

  2. 40 CFR 721.5262 - 2,7-Naphthalenedisulfonic acid, 5-[[4-chloro-6-[substituted] amino]-1,3,5-triazin-2-yl]amino]-4...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, trisodium salt (generic). 721.5262 Section 721.5262...,7-Naphthalenedisulfonic acid, 5- amino]-1,3,5-triazin-2-yl]amino]-4-hydroxy-3- -, trisodium salt... identified generically as 2,7-Naphthalenedisulfonic acid, 5-......

  3. Photo- and thermochromic spirans. 16. * 2-oxo-3-phenyl-5,5-dimethylspiro(1,3-oxazolidine-4,2'-(2H) chromenes)

    SciTech Connect

    Luk'yanov, B.S.; Chernysh, Y.E.; Minkin, V.I.; Nivorozhkin, L.E.

    1986-02-01

    New spirans of the 5,5-dimethyl-3-phenyl-2-oxazolidone series that display photochromic properties in alcohol solutions at about-80/sup 0/C were synthesized. The photoinduced forms are characterized by the presence of two long-wave absorption bands at 350-420 nm and 500-650 nm. The /sup 1/H and /sup 13/C NMR spectra were studied. Anisochronicity of the diastereotopic methyl groups of the oxazolidone ring shows up respectively. only in the /sup 13/C NMR spectra.

  4. Identification of 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) and 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF) with DNA breaking activity in soy sauce.

    PubMed

    Li, X; Hiramoto, K; Yoshida, M; Kato, T; Kikugawa, K

    1998-04-01

    Components with DNA breaking activity in soy sauce were investigated. It was found that there were water soluble high molecular weight DNA breaking components in soy sauce. Two DNA breaking components in the ethyl acetate extract of soy sauce were identified as fragrant components, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) and 4-hydroxy-2(or 5)-ethyl-5(or 2)-methyl-3(2H)-furanone (HEMF), in addition to the previously characterized DNA breaking fragrant component 4-hydroxy-5-methyl-3(2H)-furanone (HMF) (Hiramoto et al., 1996b). Characterization of DNA breaking activity of HEMF was performed, and the mechanisms for the breaking were considered. HEMF cleaved the single strands of supercoiled pBR 322 DNA at pH 7.4 dose dependently and time dependently. DNA breaking was inhibited by superoxide dismutase, catalase, hydroxyl radical scavengers, spin trapping agents and metal chelators, and enhanced by Fe(III) ion. Electron spin resonance-spin trapping technique revealed the generation of hydroxyl radical. Hence, active oxygen species derived from interaction of HEMF with metal ions and oxygen participated in the cleavage. HEMF exhibited mutagenicity to Salmonella typhimurium TA100 without metabolic activation and induced micronucleated mouse peripheral reticulocytes. PMID:9651047

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

    PubMed Central

    Farahat, Abdelbasset A.; Boykin, David W.

    2014-01-01

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

  6. A structural study of (1RS,2SR,3RS,4SR,5RS)-2,4-dibenzoyl-1,3,5-triphenylcyclohexan-1-ol chloroform hemisolvate and (1RS,2SR,3RS,4SR,5RS)-2,4-dibenzoyl-1-phenyl-3,5-bis(2-methoxyphenyl)cyclohexan-1-ol.

    PubMed

    Minyaev, Mikhail E; Roitershtein, Dmitrii M; Nifant'ev, Ilya E; Ananyev, Ivan V; Minyaeva, Tatyana V; Mikhaylyev, Timofey A

    2015-06-01

    (1RS,2SR,3RS,4SR,5RS)-2,4-Dibenzoyl-1,3,5-triphenylcyclohexan-1-ol or (4-hydroxy-2,4,6-triphenylcyclohexane-1,3-diyl)bis(phenylmethanone), C38H32O3, (1), is formed as a by-product in the NaOH-catalyzed synthesis of 1,3,5-triphenylpentane-1,5-dione from acetophenone and benzaldehyde. Single crystals of the chloroform hemisolvate, C38H32O3·0.5CHCl3, were grown from chloroform. The structure has triclinic (P1) symmetry. One diastereomer [as a pair of (1RS,2SR,3RS,4SR,5RS)-enantiomers] of (1) has been found in the crystal structure and confirmed by NMR studies. The dichoromethane hemisolvate has been reported previously [Zhang et al. (2007). Acta Cryst. E63, o4652]. (1RS,2SR,3RS,4SR,5RS)-2,4-Dibenzoyl-3,5-bis(2-methoxyphenyl)-1-phenylcyclohexan-1-ol or [4-hydroxy-2,6-bis(2-methoxyphenyl)-4-phenylcyclohexane-1,3-diyl]bis(phenylmethanone), C40H36O5, (2), is also formed as a by-product, under the same conditions, from acetophenone and 2-methoxybenzaldehyde. Crystals of (2) have been grown from chloroform. The structure has orthorhombic (Pca2₁) symmetry. A diastereomer of (2) possesses the same configuration as (1). In both structures, the cyclohexane ring adopts a chair conformation with all bulky groups (benzoyl, phenyl and 2-methoxyphenyl) in equatorial positions. The molecules of (1) and (2) both display one intramolecular O-H···O hydrogen bond. PMID:26044332

  7. Synthesis, resolution and anticonvulsant activity of chiral N-1'-ethyl,N-3'-(1-phenylethyl)-(R,S)-2'H,3H,5'H-spiro-(2-benzofuran-1,4'-imidazolidine)-2',3,5'-trione diastereomers.

    PubMed

    Sadarangani, Ishwar R; Bhatia, Souful; Amarante, Daniel; Lengyel, Istvan; Stephani, Ralph A

    2012-04-01

    Four new N-1',N-3'-disubstituted-2'H,3H,5'H-spiro-(2-benzofuran-1,4'-imidazolidine)-2',3,5'-triones bearing a chiral N-3' substituent were synthesized, resolved and their anticonvulsant activity was obtained and determined that the activity was not stereoselective. PMID:22401865

  8. {[CuSn5 Sb3 ](2-) }2 : A Dimer of Inhomogeneous Superatoms.

    PubMed

    Wilson, Robert J; Broeckaert, Lies; Spitzer, Fabian; Weigend, Florian; Dehnen, Stefanie

    2016-09-19

    Reaction of the binary Zintl anion (Sn2 Sb2 )(2-) with the β-diketiminato complex [LCu(NCMe)] (L=nacnac=[(N(C6 H3 (i) Pr2 -2,6)C(Me))2 CH](-) ) in ethylenediamine or DMF affords the ternary cluster dimer {[CuSn5 Sb3 ](2-) }2 (1) as its [K(crypt-222)](+) salt. The chemical formulation of 1 is supported by energy-dispersive X-ray spectroscopy (EDX) and quantum chemical calculations. Each monomeric part of the dimer represents a trimetallic "[CuSn5 Sb3 ](2-) " cluster, with an architecture in between a tricapped trigonal prism and a capped square antiprism. As shown by quantum chemical investigations, the presence of Sb atoms and, in particular, of Cu atoms in the cluster skeleton makes the monomeric unit behave like an inhomogeneous superatom, which clearly prefers to dimerize, thereby producing a relatively short, yet virtually non-bonding Cu⋅⋅⋅Cu distance. PMID:27558912

  9. Comparative covalent protein binding of 2,5-hexanedione and 3-acetyl-2,5-hexanedione in the rat.

    PubMed

    DeCaprio, Anthony P; Kinney, Elizabeth A; LoPachin, Richard M

    2009-01-01

    2,5-Hexanedione (HD) is the metabolite implicated in n-hexane neurotoxicity. This gamma-diketone reacts with protein lysine amines to form 2,5-dimethylpyrrole adducts. Pyrrole adduction of neurofilaments (NF) and/or other axonal proteins was proposed as a critical step in the neuropathy. While pyrrole adduction is widely accepted as necessary, subsequent pyrrole oxidation, which may result in protein cross-linking, was alternatively postulated as the critical mechanistic step. Previous studies have indicated that 3-acetyl-2,5-HD (AcHD), an analogue that forms pyrroles that do not oxidize, was not neurotoxic in rats. However, relative levels of pyrrole adduction of NF or other axonal proteins were not reported. In the present study, groups of 6 male Wistar rats were given saline, [1,6-(14)C]-HD (3 mmol/kg/d), or [5-(14)C]-AcHD (0.1 mmol/kg/d), i.p. for 21 d. HD- and AcHD-treated rats lost 10% and gained 14% body weight, respectively, compared to a 22% gain for control rats. At termination, HD- and AcHD-treated rats exhibited mean scores of 3.5 and 1.4, respectively, for hindlimb weakness (0-5 scale). Incorporation of radiolabel from HD was 27.8 +/- 3.9, 13.9 +/- 2.6, and 7.8 +/- 0.6 nmol/mg in plasma protein, purified globin, and axonal cytoskeletal proteins, respectively, compared to 0.6 +/- 0.1, 1.6 +/- 0.5, and 1.0 +/- 0.1 for AcHD. Binding of HD to the NF-L, -M, and -H subunit proteins from treated animals was 4-, 24-, and 13-fold higher, respectively, that that of AcHD, indicating differing stoichiometry and patterns of NF adduction for the two diketones. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis of globin and NF proteins did not demonstrate protein cross-linking for either diketone at the dose levels and time period examined. These results indicate that that the lack of neurotoxicity previously reported for AcHD may reflect differences in adduct levels at critical axonal target sites rather than an inability to form cross

  10. Catalytic cycloalumination in steroid chemistry II: selective functionalization of 2'-methylidene-2',3'-ethano-(5α)-cholestane.

    PubMed

    D'yakonov, Vladimir A; Tuktarova, Regina A; Islamov, Ilgiz I; Khalilov, Leonard M; Dzhemilev, Usein M

    2013-12-11

    The catalytic cycloalumination of 2'-methylidene-2',3'-ethano-(5α)-cholestane with Et3Al catalyzed by Cp2ZrCl2 was performed for the first time to give spiro[2',3'-ethano-(5α)-cholestane-2',3″-aluminacyclopentane] in a ~75% yield and with high stereoselectivity (>98%). The obtained cyclic organoaluminum compound was transformed in situ into heterocyclic spiran derivatives of 2',3'-ethano-(5α)-cholestane. PMID:24075970

  11. Aromatic derivatives of 2,3-dihydro-1H-1,5-benzodiazepine

    SciTech Connect

    Orlov, V.D.; Desenko, S.M.; Kiroga, Kh.

    1987-09-01

    The formation of 2,2,4-trisubstituted 2,3-dihydro-1H-1,5-benzodiazepines in the reactions of acetylarenes with 4-ethoxy- and 3,5-dimethyl-1,2-phenylenediamine was studied. The effect of the substituents on the individual stages of the reactions is discussed. A quantum-chemical calculation of the relative nucleophilicity of 1,2-phenylenediamine, 2,3-diaminopyridine, and 3,4-diaminofurazan was undertaken.

  12. Formation of hydrogen-bonded complexes of 3,3',5,5'-tetrabromo-2,2'-biphenol with MTBD and triethylamine

    NASA Astrophysics Data System (ADS)

    Wojciechowski, Grzegorz; Brzezinski, Bogumil

    2002-10-01

    The complexes of 3,3',5,5'-tetrabromo-2,2'-biphenol (TBBPh) with 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD) and triethylamine (TEA) were studied by FTIR spectroscopy. In chloroform and in acetonitrile a proton transfer from TBBPh to N-bases (MTBD, TEA) occurs. In chloroform solution the protonated N-base molecules are hydrogen-bonded to the deprotonated TBBPh molecules, whereas in acetonitrile the complexes dissociate. The intra- as well as intermolecular hydrogen bonds within the chains show large proton polarizability.

  13. Regioselective [3+2] cycloaddition of chalcones with a sugar azide: easy access to 1-(5-deoxy-D-xylofuranos-5-yl)-4,5-disubstituted-1H-1,2,3-triazoles.

    PubMed

    Singh, Nimisha; Pandey, S K; Tripathi, Rama P

    2010-08-16

    [3+2] Cycloaddition of 5-azido-5-deoxy-1,2-O-isopropylidene-alpha-d-xylofuranose with 1,3-diphenyl-prop-3-enones, followed by oxidation of the intermediate triazolines in a tandem manner, led to the regioselective formation of 4-benzoyl-1-(5-deoxy-1,2-O-isopropylidene-alpha-d-xylofuranos-5-yl)-5-phenyl-1H-1,2,3-triazoles in moderate to good yields. PMID:20579636

  14. Syntheses, spectral, X-ray and DFT studies of 5-benzyl-N-phenyl-1,3,4-thiadiazol-2-amine, 2-(5-phenyl-1,3,4-thiadiazol-2-yl) pyridine and 2-(5-methyl-1,3,4-thiadiazole-2-ylthio)-5-methyl-1,3,4-thiadiazole obtained by Mn(II) catalyzed reactions

    NASA Astrophysics Data System (ADS)

    Dani, R. K.; Bharty, M. K.; Kushawaha, S. K.; Paswan, S.; Prakash, Om; Singh, Ranjan K.; Singh, N. K.

    2013-12-01

    New compounds 5-benzyl-N-phenyl-1,3,4-thiadiazol-2-amine (Bptha, 1), 2-(5-phenyl-1,3,4-thiadiazol-2-yl) pyridine (Pthp, 2) and 2-(5-methyl-1,3,4-thiadiazole-2-ylthio)-5-methyl-1,3,4-thiadiazole (Mtmth, 3) have been synthesized and characterized with the aid of elemental analyses, IR, NMR and single crystal X-ray data. The structure of compounds 1, 2 and 3 are stabilized via intramolecular as well as intermolecular hydrogen bonding and crystallize in monoclinic system with space group P 1, P21/n and P 1, respectively. During the course of reaction, the substituted thiosemicarbazide/thiohydrazide get cyclized into the corresponding thiadiazole in the presence of manganese(II) nitrate via loss of H2O to yield compounds 1 and 2. However condensation occurred in the case of 5-methyl-1,3,4-thiadiazole-2-thiol which yielded 2-(5-methyl-1,3,4-thiadiazole-2-ylthio)-5-methyl-1,3,4-thiadiazole (3) by loss of one mole of H2S from two moles of 5-methyl-1,3,4-thiadiazole-2-thiol in the presence of manganese(II) acetate. The geometry optimization has been performed using DFT method and geometrical parameters thus obtained for the compounds have been compared with their single crystal X-ray data. The negative values of HOMO and LUMO energies for the molecules indicate that they are stable. The electronic transition from the ground state to the excited state due to a transfer of electrons from the HOMO to LUMO levels is mainly associated with the π⋯π transition.

  15. Synthesis and antifungal activity of natural product-based 6-alkyl-2 3 4 5-tetrahydropyridines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seven 6-alkyl-2,3,4,5-tetrahydropyridines (5a–5g) that mimic the natural products piperideines that were recently identified in the fire ant venom have been synthesized. Compounds 5c–5g with the C-6 alkyl chain lengths from C14 to C18 showed varying degrees of antifungal activities, with 5e (6-hexa...

  16. Outcomes of the 5-4-3-2-1 Go Childhood Obesity Community Trial

    ERIC Educational Resources Information Center

    Evans, W. Douglas; Christoffel, Katherine K.; Necheles, Jonathan; Becker, Adam B.; Snider, Jeremy

    2011-01-01

    Objectives: To determine effects of the "5-4-3-2-1 Go" community social marketing campaign on obesity risk factors. Methods: We randomly assigned 524 parents of 3- to 7-year-old children to receive "5-4-3-2-1 Go" counseling or not. We surveyed parents about "5-4-3-2-1 Go!" behaviors and perceptions of children's behaviors at baseline and one year…

  17. Laser-Induced Photochromic Centers in Ce(3+):La2Be2O5

    NASA Technical Reports Server (NTRS)

    Cheung, Y. M.; Gayen, S. K.; Gualtieri, D. M.

    1995-01-01

    Intense 355-nm excitation of the lowest 4f to 5d transition of Ce(3+):La2Be2O5 leads to a brownish coloration of the crystal due to the formation of stable photochromic centers. These centers are characterized by a broadband absorption spectrum that spans the 220-840 nm spectral range. Since they can be readily bleached by optical excitation into their absorption band, the centers are photochromic. They are produced by a two-step photoionization of Ce(3+) ions followed by attachment of the detached electrons at trapping sites in the crystal. The dependence of the number of centers on laser intensity and length of exposure have been measured, and the kinetics of growth have been studied.

  18. Synthesis, characterization and initial evaluation of 5-nitro-1-(trifluoromethyl)-3H-1λ3,2-benziodaoxol-3-one

    PubMed Central

    Santschi, Nico; Sarott, Roman C; Otth, Elisabeth; Kissner, Reinhard

    2014-01-01

    Summary The synthesis of 5-nitro-1-(trifluoromethyl)-3H-1λ3,2-benziodaoxol-3-one (3), a hypervalent-iodine-based electrophilic trifluoromethylating reagent, is described. Whereas considerations based on cyclic voltammetry and X-ray structural properties would predict an inferior reactivity when compared to the non-nitrated derivative 2, 19F NMR kinetic studies showed that this new derivative is almost one order of magnitude more reactive. Furthermore, differential scanning calorimetry measurements indicated that, in addition, it is also safer to handle. PMID:24454557

  19. Hydrothermal synthesis and characterization of the lutetium borate-nitrate Lu2B2O5(NO3)2·2H2O

    NASA Astrophysics Data System (ADS)

    Ortner, Teresa S.; Wurst, Klaus; Hejny, Clivia; Huppertz, Hubert

    2016-01-01

    The lutetium diborate-dinitrate Lu2B2O5(NO3)2·2H2O was discovered through a hydrothermal synthesis from Lu(NO3)3·H2O and H3BO3. The compound crystallizes in the space group P 1 ̅ (no. 2) with the lattice parameters a=789.52(5), b=988.62(6), c=1460.33(8) pm, α=90.83(1), β=101.75(1), and γ=110.02(1)° (Z=4). Isolated [B2O5]4- units show coplanar alignment and the coordinating [NO3]- groups are stacked perpendicular to the borate plane. Thereby, a novel, open arrangement solely built up from diborate and nitrate groups at a 1:1 ratio is formed. Additionally, Lu2B2O5(NO3)2·2H2O is characterized by vibrational spectroscopy (IR/Raman).

  20. Plant Transient Analysis for TAPS-3 and 4 using RELAP-5/MOD 3.2

    SciTech Connect

    Sharma, S.L.; Banerjee, S.; Rammohan, H.P.; Malhotra, P.K; Ghadge, S.G.; Bajaj, S.S.

    2006-07-01

    Tarapur Atomic Power Station- 3 and 4 (TAPS-3 and 4) are 540 Mwe Pressurised Heavy Water Reactors (PHWR). This paper presents the results of transient analysis performed to investigate the variations in different parameters of the power plant due to a spurious SETBACK signal which results in power reduction from 100% to 65% FP at a rate of 0.5% FP/sec. The analysis has been done using system thermal hydraulics code RELAP5/MOD3.2. Although the code has been widely used for modeling the Pressurised Water Reactors (PWR); Modeling of Indian PHWRs, which are horizontal pressure tube type reactors, has been done using the code for this analysis. Here the overall thermal hydraulics of the plant as well as various control systems along with trip and actuation logics have been simulated. The variation of different parameters like SG pressure, PHT pressure, SG level, etc. have been studied. An additional study has been done to evaluate the performance of the steam generator at different power levels. (authors)

  1. A toxological study of 3,6-BIS(3,5-Dimethyl-1-1-Pyrazolyl)1,2-Dihydro-1,2,4,5-Tetrazine

    SciTech Connect

    London, J.E.

    1993-03-01

    The acute oral LD[sub 30/50] values for 3,6-BIS(3,5-Dimethyl-1-Pyrazolyl)-1,2-Dihydro-1,2,4,5-Tetrazine BIS(DMP)DHT are greater than 5g/kg. According to classical guidelines, the material would be considered only slightly toxic or practically nontoxic in both rats and mice. The sensitization study in the guinea pig did not show BIS(DMP)SHT to have potential sensitizing effects. Skin application studies on the rabbit demonstrated the material was cutaneously nonirritating. This material was also nonirritating in the rabbit eye application studies.

  2. A toxological study of 3,6-BIS(3,5-Dimethyl-1-1-Pyrazolyl)1,2-Dihydro-1,2,4,5-Tetrazine

    SciTech Connect

    London, J.E.

    1993-03-01

    The acute oral LD{sub 30/50} values for 3,6-BIS(3,5-Dimethyl-1-Pyrazolyl)-1,2-Dihydro-1,2,4,5-Tetrazine BIS(DMP)DHT are greater than 5g/kg. According to classical guidelines, the material would be considered only slightly toxic or practically nontoxic in both rats and mice. The sensitization study in the guinea pig did not show BIS(DMP)SHT to have potential sensitizing effects. Skin application studies on the rabbit demonstrated the material was cutaneously nonirritating. This material was also nonirritating in the rabbit eye application studies.

  3. Antichagasic and trichomonacidal activity of 1-substituted 2-benzyl-5-nitroindazolin-3-ones and 3-alkoxy-2-benzyl-5-nitro-2H-indazoles.

    PubMed

    Fonseca-Berzal, Cristina; Ibáñez-Escribano, Alexandra; Reviriego, Felipe; Cumella, José; Morales, Paula; Jagerovic, Nadine; Nogal-Ruiz, Juan José; Escario, José Antonio; da Silva, Patricia Bernardino; Soeiro, Maria de Nazaré C; Gómez-Barrio, Alicia; Arán, Vicente J

    2016-06-10

    Two series of new 5-nitroindazole derivatives, 1-substituted 2-benzylindazolin-3-ones (6-29, series A) and 3-alkoxy-2-benzyl-2H-indazoles (30-37, series B), containing differently functionalized chains at position 1 and 3, respectively, have been synthesized starting from 2-benzyl-5-nitroindazolin-3-one 5, and evaluated against the protozoan parasites Trypanosoma cruzi and Trichomonas vaginalis, etiological agents of Chagas disease and trichomonosis, respectively. Many indazolinones of series A were efficient against different morphological forms of T. cruzi CL Brener strain (compounds 6, 7, 9, 10 and 19-21: IC50 = 1.58-4.19 μM for epimastigotes; compounds 6, 19-21 and 24: IC50 = 0.22-0.54 μM for amastigotes) being as potent as the reference drug benznidazole. SAR analysis suggests that electron-donating groups at position 1 of indazolinone ring are associated with an improved antichagasic activity. Moreover, compounds of series A displayed low unspecific toxicities against an in vitro model of mammalian cells (fibroblasts), which were reflected in high values of the selectivity indexes (SI). Compound 20 was also very efficient against amastigotes from Tulahuen and Y strains of T. cruzi (IC50 = 0.81 and 0.60 μM, respectively), showing low toxicity towards cardiac cells (LC50 > 100 μM). In what concerns compounds of series B, some of them displayed moderate activity against trophozoites of a metronidazole-sensitive isolate of T. vaginalis (35 and 36: IC50 = 9.82 and 7.25 μM, respectively), with low unspecific toxicity towards Vero cells. Compound 36 was also active against a metronidazole-resistant isolate (IC50 = 9.11 μM) and can thus be considered a good prototype for the development of drugs directed to T. vaginalis resistant to 5-nitroimidazoles. PMID:27017556

  4. 40 CFR 721.10716 - Phenol, 2,6-dimethyl-, homopolymer, ether with 2,2',3,3',5,5'-hexamethyl[1,1'-biphenyl]-4,4'-diol...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Phenol, 2,6-dimethyl-, homopolymer... Phenol, 2,6-dimethyl-, homopolymer, ether with 2,2',3,3',5,5'-hexamethyl -4,4'-diol (2:1),bis ether. (a... phenol, 2,6-dimethyl-, homopolymer, ether with 2,2',3,3',5,5'-hexamethyl -4,4'-diol (2:1),bis ether...

  5. Optimization of synthesis conditions and composition of blue phosphors [(B2O3)0.5(Al2O3)0.5] · 2SiO2: Eu2+

    NASA Astrophysics Data System (ADS)

    Gurin, N. T.; Paksyutov, K. V.; Terent'ev, M. A.; Shirokov, A. V.

    2009-09-01

    It is found that [(B2O3)0.5(Al2O3)0.5] · 2SiO2: Eu2+ systems with different concentrations of europium exhibit intense photoluminescence in the blue-violet range. When the system is excited by a 325-nm helium-cadmium laser, the spectra of blue phosphors exhibit a maximum in the interval 419-439 nm, while excitation by a pulsed nitrogen laser with a wavelength of 337 nm causes luminescence between 429 and 461 nm. Phosphor with the composition [(B2O3)0.5(Al2O3)0.5] · 2SiO2: Eu (3 mol %) ( x = 0.151, y = 0.062) excited by the radiation of a helium-cadmium laser and phosphor of the same composition having been subjected to additional vacuum annealing and excited by the radiation of a nitrogen laser ( x = 0.145, y = 0.084) are found to be optimal to provide primary blue color in the EBU and NTSC TV standards. Phosphors of the composition [(B2O3)0.5(Al2O3)0.5] · 2SiO2: Eu2+ (7 mol %) offer the highest luminescence intensity both before and after vacuum annealing.

  6. First-principles studies on Ti 3Si 0.5Ge 0.5C 2 under pressure

    NASA Astrophysics Data System (ADS)

    Feng, Wenxia; Hu, Haiquan; Cui, Shouxin; Zhang, Guiqing; Lv, Zengtao; Wu, Cheng

    2011-11-01

    The structural, electronic and elastic properties of Ti 3Si 0.5Ge 0.5C 2 have been investigated by using the pseudopotential plane-wave method within the density-functional theory. Our calculated equation of state (EOS) is consistent with the experimental results. The density of states (DOS) indicates that Ti 3Si xGe 1- xC 2 ( x=0, 0.5, 1.0) are metallic, and these compounds have nearly the same electrical conductivity. The elastic constants for Ti 3Si 0.5Ge 0.5C 2 are obtained at zero pressure, which is compared to Ti 3SiC 2 and Ti 3GeC 2. We can conclude that Ti 3Si 0.5Ge 0.5C 2 is brittle in nature by analyzing the ratio between bulk and shear moduli. There appears to be little effect on the electronic and elastic properties with the Ge substitution to Si atoms in Ti 3SiC 2.

  7. 5,5′-Bis(naphthalen-2-yl)-2,2′-bi(1,3,4-oxadiazole)

    PubMed Central

    Wang, Haitao; Jia, Xiaoshi; Qu, Songnan; Bai, Binglian; Li, Min

    2011-01-01

    The title mol­ecule, C24H14N4O2, lies on an inversion centre and the asymmetric unit containg one half-mol­ecule. The naphthalene ring systems are twisted slightly with respect to the oxadiazole rings, making a dihedral angle of 1.36 (6)°. These mol­ecules are π-stacked along the crystallographic a axis, with an inter­planar distance of 3.337 (1) Å. Adjacent mol­ecules are slipped from the ‘ideal’ cofacial π-stack in both the long and short mol­ecular axis (the long mol­ecular axis is defined as the line through the naphthalene C atom in the 6-position and the mol­ecular center, the short mol­ecular axis is in the mol­ecular plane perpendicular to it). The slip distance along the long mol­ecular axis (S 1) is 7.064 (1) Å, nearly a two-ring-length displacement. The side slip (S 2, along the short mol­ecular axis) is 1.159 (8) Å. PMID:22199854

  8. A (3 + 3)-dimensional "hypercubic" oxide-ionic conductor: type II Bi2O3-Nb2O5.

    PubMed

    Ling, Chris D; Schmid, Siegbert; Blanchard, Peter E R; Petříček, Vaclav; McIntyre, Garry J; Sharma, Neeraj; Maljuk, Andrey; Yaremchenko, Aleksey A; Kharton, Vladislav V; Gutmann, Matthias; Withers, Ray L

    2013-05-01

    The high-temperature cubic form of bismuth oxide, δ-Bi2O3, is the best intermediate-temperature oxide-ionic conductor known. The most elegant way of stabilizing δ-Bi2O3 to room temperature, while preserving a large part of its conductivity, is by doping with higher valent transition metals to create wide solid-solutions fields with exceedingly rare and complex (3 + 3)-dimensional incommensurately modulated "hypercubic" structures. These materials remain poorly understood because no such structure has ever been quantitatively solved and refined, due to both the complexity of the problem and a lack of adequate experimental data. We have addressed this by growing a large (centimeter scale) crystal using a novel refluxing floating-zone method, collecting high-quality single-crystal neutron diffraction data, and treating its structure together with X-ray diffraction data within the superspace symmetry formalism. The structure can be understood as an "inflated" pyrochlore, in which corner-connected NbO6 octahedral chains move smoothly apart to accommodate the solid solution. While some oxide vacancies are ordered into these chains, the rest are distributed throughout a continuous three-dimensional network of wide δ-Bi2O3-like channels, explaining the high oxide-ionic conductivity compared to commensurately modulated phases in the same pseudobinary system. PMID:23570580

  9. 2,2-Dimethyl-5-[(pyridin-2-yl-amino)-methyl-idene]-1,3-dioxane-4,6-dione.

    PubMed

    Shi, Jian-You; Li, Jin-Qi; Tong, Rong-Sheng; Lin, He; Lu, Chen

    2011-01-01

    In the title compound, C(12)H(12)N(2)O(4), the dihedral angle between the pyridine and enamine planes is 3.5 (3)°, while the angle between the dioxanedione (seven atoms) and enamine planes is 4.6 (3)°. The dioxane ring approximates an envelope conformation. PMID:21522947

  10. Fidelity of binding of the guanidinium nucleic acid (DNG) d(Tg)4-T-azido with short strand DNA oligomers (A5G3A5, GA4G3A4G, G2A3G3A3G2, G2A2G5A2G2). A kinetic and thermodynamic study.

    PubMed

    Blaskó, A; Minyat, E E; Dempcy, R O; Bruice, T C

    1997-06-24

    Short strand DNA oligomers (A5G3A5, GA4G3A4G, G2A3G3A3G2, and G2A2G5A2G2) and the guanidinium (g) linked thymidyl nucleoside d(Tg)4-T-azido associate as triplexes. The melting temperatures, Tm, the association and dissociation kinetic and thermodynamic parameters and activation energies for the triplexes were determined by UV thermal analysis. The hypochromic shift and Tm for triplex formation increases with increase in concentration and decreases with the number of mismatches. The melting temperatures are between 35 and 55 degrees C in the range of ionic strength of 0.06-0.24 and decrease with increase in ionic strength at 100 deg/(ionic strength unit). The melting and cooling curves exhibit hysteresis behavior in the temperature range 5-95 degrees C at 0.2 deg/min thermal rate. From these curves, the rate constants and the energies of activation for association (k(on), E(on)) and dissociation (k(off), E(off)) processes were obtained. The second-order rate constants, k(on), for the triplex formation at 288 K are between 10 and 500 M(-2) s(-1). Values of k(on) increase with the decrease in the ionic strength. The first order rate constants for the dissociation, k(off), at 288 K are between 10(-6) and 40 x 10(-6) s(-1) and increase with increase in ionic strength. The energies of activation for the association and dissociation processes are in the range -22 to -9 kcal/mol and 8 to 29 kcal/mol, respectively. At 6.3 x 10(-5) M/base and at the physiological ionic strength (0.15-0.30) and below, the triplex structures formed with d(Tg)4-T-azido and A5G3A5 and GA4G3A4G have well-defined Tm values. The melting curves with G2A3G3A3G2 and G2A2G5A2G2 are very shallow with small hypochromic shifts denoting negligible binding at physiological ionic strength. Therefore, with the increase in the G content (mismatched base pairs) at a certain concentration (e.g., 6.3 x 10(-5) M/base), discrimination (change in fidelity) occurs in the formation and strength of binding of d(Tg)4-T

  11. Helical Poly(5-alkyl-2,3-thiophene)s: Controlled Synthesis and Structure Characterization

    DOE PAGESBeta

    Zhang, Hong-Hai; Ma, Chuanxu; Bonnesen, Peter V.; Zhu, Jiahua; Sumpter, Bobby G.; Carrillo, Jan-Michael Y.; Yin, Panchao; Wang, Yangyang; Li, An-Ping; Hong, Kunlun

    2016-07-12

    Whereas Poly(3-alkyl-2,5-thiophene)s (P3AT), with many potential applications, have been extensively investigated, their ortho-connected isomers, poly(5-alkyl-2,3-thiophene)s (P5AT), have never been reported because of the difficulty in their syntheses. We herein present the first synthesis of regioregular P5AT via controlled Suzuki cross-coupling polymerization with PEPPSI-IPr as catalyst, affording the polymers with tunable molecular weight, narrow polydispersity (PDI) and well-defined functional end groups at the gram scale. The helical geometry of P5AT was studied by a combination of NMR, small angle x-ray scattering (SAXS) and scanning tunneling microscopy (STM). Particularly, the single polymer chain of poly(5- 2 butyl-2,3-thiophene) (P5BT) on highly oriented pyrolyticmore » graphite (HOPG) substrates with either M or P helical conformation was directly observed by STM. The comparison of UV-vis absorption between poly(5-hexyl-2,3-thiophene) (P5HT) (λ = 345 nm) and poly(3-hexyl-2,5- thiophene) (P3HT) (λ = 450 nm) indicated that the degree of conjugation of the backbone in P5HT is less than in P3HT, which may be a consequence of the helical geometry of the former compared to the more planar geometry of the latter. Moreover, we found that P5HT can emit green fluorescence under UV (λ = 360 nm) irradiation« less

  12. N3 Protonation Induces Base Rotation of 2'-Deoxyadenosine-5'-monophosphate and Adenosine-5'-monophosphate.

    PubMed

    Wu, R R; He, C C; Hamlow, L A; Nei, Y-W; Berden, G; Oomens, J; Rodgers, M T

    2016-05-26

    Infrared multiple photon dissociation (IRMPD) action spectroscopy experiments combined with theoretical calculations are performed to investigate the stable gas-phase conformations of the protonated adenine mononucleotides, [pdAdo+H](+) and [pAdo+H](+). Conformations that are present in the experiments are elucidated via comparative analyses of the experimental IRMPD spectra and the B3LYP/6-311+G(d,p) IR spectra predicted for the conformers optimized at this level of theory. N3 protonation is preferred as it induces base rotation, which allows a strong hydrogen bond to be formed between the excess proton of adenine and the phosphate moiety. In contrast, both N1 and N7 protonation are predicted to be >35 kJ/mol less favorable than N3 protonation. Only N3 protonated conformers are present in the experiments in measurable abundance. Both the low-energy conformers computed and the experimental IRMPD spectra of [pdAdo+H](+) and [pAdo+H](+) indicate that the 2'-hydroxyl moiety does not significantly impact the structure of the most stable conformer or the IRMPD spectral profile of [pAdo+H](+) vs that of [pdAdo+H](+). However, the 2'-hydroxyl leads to a 3-fold enhancement in the IRMPD yield of [pAdo+H](+) in the fingerprint region. Comparison of present results to those reported in a previous IRMPD study of the analogous protonated adenine nucleosides allows the effects of the phosphate moiety on the gas-phase conformations to be elucidated. PMID:27138137

  13. Effect of Nb2O5 and V2O5 addition on the superconducting properties of YBa2Cu3O(y) thin films

    NASA Technical Reports Server (NTRS)

    Srinivas, S.; Bhatnagar, A. K.; Pinto, R.; Pai, S. P.; Apte, P. R.; Purandare, S. C.; Souza, C. P. D.

    1995-01-01

    The effect of Nb2O5 and V2O5 addition on the superconducting properties and microstructure of YBa2Cu3O(y) has been studied in thin films. Polycrystalline targets for laser ablation were prepared by mixing high purity V2O5 or Nb2O5 powders with a well characterized YBa2Cu3O(y) powder in the range 0 to 4 wt percent by solid state reaction method. Thin films (approximately 1500 A thickness) of the above targets were grown on (100) SrTiO3 (STO) and (100) LaAlO3 (LAO) substrates at 700 C temperature by pulsed laser deposition (PLD) technique. In the case of Nb2O5 addition we have noticed an increase in J(sub c) up to 0.5 wt percent and higher additive concentration (greater than 0.5 wt percent) have degraded the superconducting properties. However, in the case of V2O3 addition, there is an improvement in current density and microstructural properties up to 1 wt percent and the superconducting properties degrade for concentrations greater than 1 wt percent. The best J(sub c) for 0.5 wt percent of Nb2O5 added YBCO thin film is 1.6 x 10(exp 6) A/sq cm and for that of V2O5 added sample is 3.4 x 10(exp 6) A/sq cm at 77 K as compared to the pure YBa2Cu3O(y) (YBCO) film J(sub c) (1.2 x 10(exp 6) A/sq cm) observed on STO substrates. The reason for improvement in J(sub c) and microstructural properties in the case of V2O5 addition could be due to the low melting of V2O5 (690 C) which can act as a very good surfactant during deposition. Over all, we have realized that Nb2O5 addition or V2O5 addition to YBCO have shown significant improvement over the undoped YBa2Cu3O(7-x) films grown under identical conditions.

  14. X-ray studies of 2-amino-5-oxo-4-propyl-4,5-dihydropyrano[3,2- c]chromene-3-carbonitrile

    NASA Astrophysics Data System (ADS)

    Sharma, S.; Banerjee, B.; Brahmachari, G.; Kant, R.; Gupta, V. K.

    2015-11-01

    The carbonitrile compound, 2-amino-5-oxo-4-propyl-4,5-dihydropyrano[3,2- c]chromene-3-carbonitrile was synthesized, in 83% yield, by one-pot multicomponent reaction of butyraldehyde, malononitrile and 4-hydroxycoumarin using 10 mol% urea as an organo-catalyst at room temperature, and its crystal structure was determined by X-ray diffraction technique. The crystals are triclinic, a = 7.7379(5), b = 8.7520(6), c = 11.6589(5) Å, α = 96.668(4)°, β = 100.033(4)°, γ = 112.547(6)°, Z = 2, sp. gr. P. Both pyran rings in the molecule adopt a boat conformation. The crystal structure is stabilized by N-H···O and N-H···N hydrogen bonds.

  15. Nucleosides of 4-methylthio-1,2,3-triazol-5-yl-carboxylic acid derivatives

    SciTech Connect

    Shingarova, I.D.; Yartseva, I.V.; Preobrazhenskaya, M.N.

    1987-08-01

    2-..beta..-D-Ribofuranosyl-4-methylthio-5-methoxycarbonyl-1,2,3-triazole was obtained by fusing 4-methylthio-5-methoxycarbonyl-1,2,3-triazole together with tetraacyl-D-ribofuranose, followed by deacylation, and its amide and hydrazide were prepared. The structures of the new nucleosides were established by converting them into known 2-nucleosides of 1,2,3-triazol-4-yl-carboxylic acid derivatives. By comparing PMR spectra with previously reported PMR spectra for the isomeric 1- and 2-nucleosides of 1,2,3-triazol-4-yl-carboxylic acid derivatives, the synthesized nucleosides could be assigned to 2-substituted triazoles.

  16. Effects of the substitution of P2O5 by B2O3 on the structure and dielectric properties in (90-x) P2O5-xB2O3-10Fe2O3 glasses.

    PubMed

    Sdiri, N; Elhouichet, H; Dhaou, H; Mokhtar, F

    2014-01-01

    90%[xB2O3 (1-x) P2O5] 10%Fe2O3, glass systems where (x=0 mol%, 5 mol%, 10 mol%, 15 mol%, 20 mol%) was prepared via a melt quenching technique. The structure of glass is investigated at room temperature by, Raman and EPR spectroscopy. Raman studies have been performed on these glasses to examine the distribution of different borate and phosphate structural groups. We have noted an increase from 3 to 4 in the coordination number of the boron atoms from 3 to 4, i.e., the conversion of the BO3 triangular structural units into BO4 tetrahedra. The samples have been investigated by means of electron paramagnetic resonance (EPR). The results obtained from the gef=4.28 EPR line are typical of the occurrence of iron (III) occupying substitutional sites. Moreover, the dielectric sizes such as ε'(ω), ε″(ω), imaginary parts of the electrical modulus, M(*)(ω) and the loss tanδ, their variation with frequency at room temperature show a decrease in relaxation intensity with an increase in the concentration of (B2O3). On the present work, we have found a weak extinction index with our new glass. PMID:23995605

  17. Selective catalytic reduction of NO with NH3 over V2O5 supported on TiO2 and Al2O3: A comparative study

    NASA Astrophysics Data System (ADS)

    Huang, Xianming; Zhang, Shule; Chen, Huinan; Zhong, Qin

    2015-10-01

    This study aimed at investigating the interaction of V2O5 species with TiO2 and Al2O3 supports to understand the effect of supports on SCR reaction. Analysis by XRD, BET, UV-vis, and DFT theoretical calculations, XPS, EPR and in situ DRIFT showed that the two kinds of supports could interact with V2O5. The interaction of electron excitation and charge transfer of supports to V2O5 species was important to the formation of the reduced V2O5. These aspects increased the formation of superoxide ions that could improve the NO oxidation over V2O5/TiO2. It was responsible for the higher SCR catalytic activity of V2O5/TiO2 than V2O5/Al2O3.

  18. Phase equilibria in the oxide system Nd 2O 3-K 2O-P 2O 5

    NASA Astrophysics Data System (ADS)

    Szczygieł, Irena; Znamierowska, Teresa; Mizer, Dagmara

    2010-07-01

    A phase equilibria diagram of the partial system NdPO 4-K 3PO 4-KPO 3 has been developed as part of the research aimed at determining the phase equilibrium relationships in the oxide system Nd 2O 3-K 2O-P 2O 5. The investigations were conducted using thermoanalytical techniques, X-ray powder diffraction analysis and reflected-light microscopy. Three isopleths existing between: K 3Nd(PO 4) 2-K 4P 2O 7, NdPO 4-K 5P 3O 10 and NdPO 4-K 4P 2O 7 have been identified in the partial NdPO 4-K 3PO 4-KPO 3 system. Previously unknown potassium-neodymium phosphate "K 4Nd 2P 4O 15" has been discovered in the latter isopleth section. This phosphate exists in the solid phase up to a temperature of 890 °C at which it decomposes into the parent phosphates NdPO 4 and K 4P 2O 7. Four invariant points: two quasi-ternary eutectics, E 1 (1057 °C) and E 2 (580 °C) and two quasi-ternary peritectics, P 1 (1078 °C) and P 2 (610 °C), occur in the NdPO 4-K 3PO 4-KPO 3 region.

  19. Anisotropic swelling and microcracking of neutron irradiated Ti3AlC2-Ti5Al2C3 materials

    DOE PAGESBeta

    Ang, Caen K.; Silva, Chinthaka M.; Shih, Chunghao Phillip; Koyanagi, Takaaki; Katoh, Yutai; Zinkle, Steven J.

    2015-12-17

    Mn + 1AXn (MAX) phase materials based on Ti–Al–C have been irradiated at 400 °C (673 K) with fission neutrons to a fluence of 2 × 1025 n/m2 (E > 0.1 MeV), corresponding to ~ 2 displacements per atom (dpa). We report preliminary results of microcracking in the Al-containing MAX phase, which contained the phases Ti3AlC2 and Ti5Al2C3. Equibiaxial ring-on-ring tests of irradiated coupons showed that samples retained 10% of pre-irradiated strength. Volumetric swelling of up to 4% was observed. Phase analysis and microscopy suggest that anisotropic lattice parameter swelling caused microcracking. Lastly, variants of titanium aluminum carbide may bemore » unsuitable materials for irradiation at light water reactor-relevant temperatures.« less

  20. 40 CFR 721.5545 - 3-(Dichloroacetyl)-5-(2-furanyl)-2,2-dimethyl-oxazolidine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 3-(dichloroacetyl)-5-(2-furanyl)-2,2-dimethyloxazolidine (PMN P-93-1694) (CAS no. 121776-57-6) is...) Recordkeeping. Recordkeeping requirements as specified in § 721.125 (a), (b), (c), (d), (e), (f), (g), (h), and... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  1. 40 CFR 721.5545 - 3-(Dichloroacetyl)-5-(2-furanyl)-2,2-dimethyl-oxazolidine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 3-(dichloroacetyl)-5-(2-furanyl)-2,2-dimethyloxazolidine (PMN P-93-1694) (CAS no. 121776-57-6) is...) Recordkeeping. Recordkeeping requirements as specified in § 721.125 (a), (b), (c), (d), (e), (f), (g), (h), and... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  2. 40 CFR 721.5545 - 3-(Dichloroacetyl)-5-(2-furanyl)-2,2-dimethyl-oxazolidine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 3-(dichloroacetyl)-5-(2-furanyl)-2,2-dimethyloxazolidine (PMN P-93-1694) (CAS no. 121776-57-6) is...) Recordkeeping. Recordkeeping requirements as specified in § 721.125 (a), (b), (c), (d), (e), (f), (g), (h), and... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  3. 40 CFR 721.5545 - 3-(Dichloroacetyl)-5-(2-furanyl)-2,2-dimethyl-oxazolidine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 3-(dichloroacetyl)-5-(2-furanyl)-2,2-dimethyloxazolidine (PMN P-93-1694) (CAS no. 121776-57-6) is...) Recordkeeping. Recordkeeping requirements as specified in § 721.125 (a), (b), (c), (d), (e), (f), (g), (h), and... (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses...

  4. The 5-HT2B receptor gene maps to 2q36.3-2q37.1

    SciTech Connect

    Le Coniat, M.; Berger, R.; Choi, Doo-Sup; Maroteaux, L.

    1996-02-15

    This article reports on the localization of the serotonin 5-HT2B receptor to human chromosome 2q36.3-2q37.1 using fluorescence in situ hybridization. The structure and function of this gene, as well as its expression, remain to be investigated in the human. 9 refs.

  5. Phase transformations in hypereutectic MgO-Y2O3 nanocomposites at 5.5 GPa

    NASA Astrophysics Data System (ADS)

    Şavklıyıldız, İ.; Akdoğan, E. K.; Zhong, Z.; Wang, L.; Weidner, D.; Vaughan, M.; Croft, M. C.; Tsakalakos, T.

    2013-05-01

    Hypereutectic 0.8MgO-0.2Y2O3 nanocomposites were studied using high pressure and high temperature in situ synchrotron energy dispersive x-ray diffractometry at 5.5 GPa and 1273 K. Polymorphic transformations in the Y2O3 phase, which resulted in a quadruple phase equilibria among cubic, hexagonal, and monoclinic phases with cubic MgO, were observed at 298 K under 5.5 GPa—a pressure much smaller than the pressures at which polymorphic transitions in macroscopic Y2O3. Time-resolved diffractometry at (1273 K, 5.5 GPa, 120 min) revealed a 0.87% expansive volumetric lattice strain in MgO, and is attributed to solid solution formation with Y2O3 which is otherwise absent at ambient conditions. The residual MgO unit cell volume expansion is 0.69% at 298 K, which is indicative that yttrium remained in solid solution. The macroscopic shrinkage due to densification at (1273 K, 5.5 GPa, 120 min) is 3.45% by volume. The partial molar volume of Y3+ in the solid solution is smaller than its molar volume in the pure state per thermodynamic considerations. The importance of repulsion among O2- ions in the immediate vicinity of a Mg2+ vacancy as well as misfit strain due to differences in ionic radii upon Y3+ substitution on Mg2+ sites is presented. A self-consistent model and explanation for the observed concomitant occurrence of cubic → monoclinic and cubic → hexagonal polymorphic transitions in Y2O3 and their stabilization at room temperature is proposed.

  6. Long-range states of the NaRb molecule near the Na (3 2S1 /2 )+Rb (5 2P3 /2 ) asymptote

    NASA Astrophysics Data System (ADS)

    Zhu, Bing; Li, Xiaoke; He, Xiaodong; Guo, Mingyang; Wang, Fudong; Vexiau, Romain; Bouloufa-Maafa, Nadia; Dulieu, Olivier; Wang, Dajun

    2016-01-01

    We report a high-resolution spectroscopic investigation of the long-range states of the 23Na87Rb molecule near its Na (3 2S1 /2 )+Rb (5 2P3 /2 ) asymptote. This study was performed with weakly bound ultracold molecules produced via magnetoassociation with an interspecies Feshbach resonance. We observed several regular vibrational series, which are assigned to the five attractive long-range states correlated with this asymptote. The vibrational levels of two of these states have sharp but complex structures due to hyperfine and Zeeman interactions. For the other states we observed significant linewidth broadenings due to strong predissociation caused by spin-orbit couplings with states correlated to the lower Na (3 2S1 /2 )+Rb (5 2P1 /2 ) asymptote. The long-range C6 van der Waals coefficients extracted from our spectrum are in good agreement with theoretical values.

  7. Synthesis, characterization, and crystal structure of 2-amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[3,2-c] pyran-3-carbonitrile

    SciTech Connect

    Sharma, S.; Banerjee, B.; Brahmachari, G.; Kant, Rajni; Gupta, V. K.

    2015-12-15

    2-Amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[3,2-c] pyran-3-carbonitrile, C{sub 16}H{sub 12}N{sub 2}O{sub 3} is synthesized via one-pot multi-component reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst. Its structure is determined by single-crystal X-ray diffraction technique The crystals are monoclinic, a = 10.7357(12), b = 8.7774(8), c = 15.0759(16) Å, β = 103.575(11)°, Z = 4, sp. gr. P2{sub 1}/n, R = 0.0551 for 1696 observed reflections. The crystal structure is stabilized by N–H···N, C–H···O, and C–H···π interactions.

  8. Magnetic structure of U2Rh3Si5 in external fields up to 14.5 T

    NASA Astrophysics Data System (ADS)

    Galli, F.; Feyerherm, R.; Prokes, K.; Nieuwenhuys, G. J.

    2000-03-01

    The intermetallic compound U2Rh3Si5 exhibits a first-order transition at 25 K into a noncollinear antiferromagnetic structure. At the lowest temperature the antiferromagnetic structure can be destroyed by a field of 14 T. Using the two-axis spectrometer E4 at the Hahn-Meitner-Institute, we have studied the magnetic structure of U2Rh3Si5 for various temperatures and magnetic fields around the magnetic phase boundary.

  9. Synthesis and properties of new derivatives of ethyl 7-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrido [2,3-d]pyrimidine-5-carboxylate.

    PubMed

    Sladowska, H; Bartoszko-Malik, A; Zawisza, T

    1990-01-01

    Condensation of diethyl 2-amino-6-methylpyridine-3,4-dicarboxylate with phenyl or cyclohexyl isocyanates gave the corresponding derivatives of ethyl 7-methyl-2,4-dioxo-1,2,3,4-tetrahydropyrido [2,3-d]pyrimidine- 5-carboxylate[(V), (VI)]. Alkylation of (V) and (VI) afforded the corresponding N-1 substituted derivatives (XI-XIX). PMID:2337441

  10. 22 CFR 501.5 - Mid-level FSO Candidate Program (Class 3, 2, or 1).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 2 2014-04-01 2014-04-01 false Mid-level FSO Candidate Program (Class 3, 2, or 1). 501.5 Section 501.5 Foreign Relations BROADCASTING BOARD OF GOVERNORS APPOINTMENT OF FOREIGN SERVICE OFFICERS § 501.5 Mid-level FSO Candidate Program (Class 3, 2, or 1). (a) General. The mid-level FSO Candidate program, under the provisions...

  11. 22 CFR 501.5 - Mid-level FSO Candidate Program (Class 3, 2, or 1).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Mid-level FSO Candidate Program (Class 3, 2, or 1). 501.5 Section 501.5 Foreign Relations BROADCASTING BOARD OF GOVERNORS APPOINTMENT OF FOREIGN SERVICE OFFICERS § 501.5 Mid-level FSO Candidate Program (Class 3, 2, or 1). (a) General. The mid-level FSO Candidate program, under the provisions...

  12. 22 CFR 501.5 - Mid-level FSO Candidate Program (Class 3, 2, or 1).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 2 2013-04-01 2009-04-01 true Mid-level FSO Candidate Program (Class 3, 2, or 1). 501.5 Section 501.5 Foreign Relations BROADCASTING BOARD OF GOVERNORS APPOINTMENT OF FOREIGN SERVICE OFFICERS § 501.5 Mid-level FSO Candidate Program (Class 3, 2, or 1). (a) General. The mid-level FSO Candidate program, under the provisions...

  13. Lasing effects in new Nd3+-doped TeO2-Nb2O5-WO3 bulk glasses

    NASA Astrophysics Data System (ADS)

    Carreaud, J.; Labruyère, A.; Dardar, H.; Moisy, F.; Duclère, J.-R.; Couderc, V.; Bertrand, A.; Dutreilh-Colas, M.; Delaizir, G.; Hayakawa, T.; Crunteanu, A.; Thomas, P.

    2015-09-01

    This paper demonstrates for the first time continuous wave (cw) and pulsed lasing effects in a 75TeO2-20NbO2.5-5WO3 glass doped with 1 mol.% in Nd3+. It is divided into two parts: The first part treats all the aspects related to the elaboration and the characterization of the materials. Thus, glasses elaborated within the TeO2-Nb2O5-WO3 ternary system show a rather high glass transition temperature Tg ∼ 375 °C, with an excellent thermal stability of ∼160 °C. Compared to glasses synthesized in either TeO2-Nb2O5 or TeO2-WO3 binary systems, glasses fabricated within such system show improved mechanical performances, with larger Young's modulus values. The structural characteristics of the samples, studied by Raman spectroscopy, are also presented. Linear optical properties (refractive index and extinction coefficient) are accessed by spectroscopic ellipsometry. As well, the optical transmission of the various bulk glasses is measured, in the case of both uncoated and coated glasses. In particular, specific anti-reflective coatings at 808 nm (laser diode pump wavelength) and 1064 nm (laser emission wavelength) are respectively deposited on the two surfaces of the sample in order to minimize the losses due to Fresnel reflections at the two glass/air interfaces. In addition, another specific surface treatment (Rmax at 1064 nm) was employed to serve as the back mirror of the laser cavity. The optical transmission data testified to the real efficiency of all these coatings. Finally, the photoluminescence properties (emission and excitation spectra, and luminescence decay curve) of the Nd3+-doped glasses, measured at room temperature for bulk samples, and as a function of temperature for powder glasses, are discussed. The second part is focused on evidencing (cw) and pulsed lasing effects in such coated bulk lasers. Cylindric samples of only a few millimeters in height and in diameter were tested and led to a laser emission around 1064 nm, characterized by a very low

  14. The niobium oxoazides [NbO(N3)3], [NbO(N3)3·2CH3CN], [(bipy)NbO(N3)3], Cs2[NbO(N3)5] and [PPh4]2[NbO(N3)5].

    PubMed

    Haiges, Ralf; Vasiliu, Monica; Dixon, David A; Christe, Karl O

    2016-06-28

    Niobium oxotriazide, [NbO(N3)3], was prepared in a fluoride-azide exchange reaction between [NbOF3] and an excess of Me3SiN3 in SO2 solution. In acetonitrile solution, the fluoride-azide exchange resulted in the isolation of the adduct [NbO(N3)3·2CH3CN]. The subsequent reaction of [NbO(N3)3] with 2,2'-bipyridine (bipy) resulted in the isolation of the bipyridine adduct [(bipy)NbO(N3)3]. The pentaazido anion [NbO(N3)5](2-) was obtained by the reaction of [NbO(N3)3] with two equivalents of ionic azide. The novel niobium oxoazides were fully characterized by their vibrational spectra, impact, friction and thermal sensitivity data and, in the case of [(bipy)NbO(N3)3], Cs2[NbO(N3)5], and [PPh4]2[NbO2(N3)5] by their X-ray crystal structures. PMID:27198621

  15. Platelet activating factor antagonist design: structure of methyl trans-5-(3,4-dimethoxyphenyl)-2,3,4,5-tetrahydro-2-oxo-4- furancarboxylate.

    PubMed

    Peterson, J R; Smillie, T J; Rogers, R D

    1989-02-15

    C14H16O6, Mr = 280.28, monoclinic, P2(1)/c, a = 6.070 (2), b = 9.526 (5), c = 22.418 (5) A, beta = 94.32 (2) degrees, V = 1293 A3, Z = 4, Dx = 1.44 g cm-3, lambda(Mo K alpha) = 0.71073 A, mu = 0.71 cm-1, F(000) = 592, T = 293 K, final R = 0.043 for 1400 observed [F0 greater than or equal to 5 sigma(F0)] reflections. The observed structure confirms a trans stereorelationship for the two substituents and an envelope conformation for the lactone ring. There is no crystallographically imposed symmetry. An analysis of the closest contacts in the cell lattice reveals two types of intermolecular interactions for this compound. PMID:2610971

  16. 40 CFR 721.10158 - 2-Pentanone, 3,5-dichloro-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (organic vapor, acid gas, or substance-specific). (ii) Hazard communication program. Requirements as... Substances § 721.10158 2-Pentanone, 3,5-dichloro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-pentanone, 3,5-dichloro- (PMN P-06-16; CAS No....

  17. 40 CFR 721.10158 - 2-Pentanone, 3,5-dichloro-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (organic vapor, acid gas, or substance-specific). (ii) Hazard communication program. Requirements as... Substances § 721.10158 2-Pentanone, 3,5-dichloro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-pentanone, 3,5-dichloro- (PMN P-06-16; CAS No....

  18. 40 CFR 721.10158 - 2-Pentanone, 3,5-dichloro-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (organic vapor, acid gas, or substance-specific). (ii) Hazard communication program. Requirements as... Substances § 721.10158 2-Pentanone, 3,5-dichloro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-pentanone, 3,5-dichloro- (PMN P-06-16; CAS No....

  19. 40 CFR 721.10158 - 2-Pentanone, 3,5-dichloro-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (organic vapor, acid gas, or substance-specific). (ii) Hazard communication program. Requirements as... Substances § 721.10158 2-Pentanone, 3,5-dichloro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-pentanone, 3,5-dichloro- (PMN P-06-16; CAS No....

  20. 40 CFR 721.10158 - 2-Pentanone, 3,5-dichloro-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (organic vapor, acid gas, or substance-specific). (ii) Hazard communication program. Requirements as... Substances § 721.10158 2-Pentanone, 3,5-dichloro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-pentanone, 3,5-dichloro- (PMN P-06-16; CAS No....

  1. Theoretical Study of Mechanism and Regioselectivity of 1,3-dipolar Cycloaddition of N-[methyl]-C-[5-nitro-2-furyl] Nitrilimine with Dimethyl 7-oxabicyclo[2,2,1]hepta-2,5-diene-2,3-dicarboxylate

    NASA Astrophysics Data System (ADS)

    Moeinpour, Farid

    2010-04-01

    The mechanism and regioselectivity of 1,3-dipolar cycloaddition of N-[methyl]-C-[5-nitro-2-furyl] nitrilimine with dimethyl 7-oxabicyclo[2,2,1]hepta-2,5-diene-2,3-dicarboxylate were investigated using activation energy calculations and density functional theory-based reactivity indexes. The reaction proceeds by an asynchronous concerted mechanism. The calculations are performed at the B3LYP/6-31G(d) level of theory and the obtained results are in agreement with experimental outcome.

  2. Visible Light Assisted Photocatalytic Hydrogen Generation by Ta2O5/Bi2O3, TaON/Bi2O3, and Ta3N5/Bi2O3 Composites

    DOE PAGESBeta

    Adhikari, Shiba; Hood, Zachary D.; More, Karren Leslie; Ivanov, Ilia N.; Zhang, Lifeng; Gross, Michael; Lachgar, Abdou

    2015-06-15

    Composites comprised of two semiconducting materials with suitable band gaps and band positions have been reported to be effective at enhancing photocatalytic activity in the visible light region of the electromagnetic spectrum. Here, we report the synthesis, complete structural and physical characterizations, and photocatalytic performance of a series of semiconducting oxide composites. UV light active tantalum oxide (Ta2O5) and visible light active tantalum oxynitride (TaON) and tantalum nitride (Ta3N5) were synthesized, and their composites with Bi2O3 were prepared in situ using benzyl alcohol as solvent. The composite prepared using equimolar amounts of Bi2O3 and Ta2O5 leads to the formation ofmore » the ternary oxide, bismuth tantalate (BiTaO4) upon calcination at 1000 °C. The composites and single phase bismuth tantalate formed were characterized by powder X-ray diffraction (PXRD), thermogravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) surface area measurement, scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–Vis diffuse reflectance spectroscopy, and photoluminescence. The photocatalytic activities of the catalysts were evaluated for generation of hydrogen using aqueous methanol solution under visible light irradiation (λ ≥ 420 nm). The results show that as-prepared composite photocatalysts extend the light absorption range and restrict photogenerated charge-carrier recombination, resulting in enhanced photocatalytic activity compared to individual phases. The mechanism for the enhanced photocatalytic activity for the heterostructured composites is elucidated based on observed activity, band positions calculations, and photoluminescence data.« less

  3. Synthesis ofN-(2-chloro-5-methylthiophenyl)-N'-(3-methyl-thiophenyl)-N'-[3H3]methylguanidine, l brace [3H3]CNS-5161 r brace

    SciTech Connect

    Gibbs, Andrew R.; Morimoto, Hiromi; VanBrocklin, Henry F.; Williams, Philip G.; Biegon, Anat

    2001-09-28

    The preparation of the title compound, [{sup 3}H{sub 3}]CNS-5161, was accomplished in three steps starting with the production of [{sup 3}H{sub 3}]iodomethane (CT{sub 3}I). The intermediate N-[{sup 3}H{sub 3}]methyl-3-(thiomethylphenyl)cyanamide was prepared in 77% yield by the addition of CT{sub 3}I to 3-(thiomethylphenyl)cyanamide, previously treated with sodium hydride. Reaction of this tritiated intermediate with 2-chloro-5-thiomethylaniline hydrochloride formed the guanidine compound [{sup 3}H{sub 3}]CNS-5161. Purification by HPLC gave the desired labeled product in an overall yield of 9% with greater than 96% radiochemical purity and a final specific activity of 66 Ci mmol{sup -1}.

  4. Synthesis, characterization, and crystal structure of 2-amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[3,2- c]pyran-3-carbonitrile

    NASA Astrophysics Data System (ADS)

    Sharma, S.; Banerjee, B.; Brahmachari, G.; Kant, Rajni; Gupta, V. K.

    2015-12-01

    2-Amino-7-methyl-5-oxo-4-phenyl-4,5-dihydropyrano[3,2- c]pyran-3-carbonitrile, C16H12N2O3 is synthesized via one-pot multi-component reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst. Its structure is determined by single-crystal X-ray diffraction technique The crystals are monoclinic, a = 10.7357(12), b = 8.7774(8), c = 15.0759(16) Å, β = 103.575(11)°, Z = 4, sp. gr. P21/ n, R = 0.0551 for 1696 observed reflections. The crystal structure is stabilized by N-H···N, C-H···O, and C-H···π interactions.

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

    NASA Astrophysics Data System (ADS)

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

    2008-12-01

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

  6. Competition between 3d and 4f magnetism in Ce2Fe2S5

    NASA Astrophysics Data System (ADS)

    Schneidewind, A.; Mills, A. M.; Schnelle, W.; Stockert, O.; Ouladdiaf, B.; Ruck, M.

    2007-03-01

    Magnetic susceptibility measurements and neutron powder diffraction were performed on the rare-earth transition-metal sulfide Ce2Fe2S5 to study the effect of the substitution of nonmagnetic La(4f0) by Ce4f1). Ce2Fe2S5, which is isostructural to La2Fe2S5, contains Fe ions within chains of iron-sulfur octahedra and tetrahedra that are interconnected by Ce ions. Two antiferromagnetic phases, both with the propagation vector τ=({1}/{2} {1}/{2} 0), are observed: at 5 K⩽T⩽80 K ordering of the Fe moments is found; at T⩽5 K the Ce ions also participate in the magnetic ordering.

  7. (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol inhibits growth of colon tumors in mice

    PubMed Central

    Son, Dong Ju; Choi, Min Gi; Choi, Jeong Soon; Nam, Kyung Tak; Kim, Hae Deun; Rodriguez, Kevin; Gann, Benjamin; Ham, Young Wan; Han, Sang Bae; Hong, Jin Tae

    2015-01-01

    In our previous study, we found that (E)-2,4-bis(p-hydroxyphenyl)-2-butenal showed anti-cancer effect, but it showed lack of stability and drug likeness. We have prepared several (E)-2,4-bis(p-hydroxyphenyl)-2-butenal analogues by Heck reaction. We selected two compounds which showed significant inhibitory effect of colon cancer cell growth. Thus, we evaluated the anti-cancer effects and possible mechanisms of one compound (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol in vitro and in vivo. In this study, we found that (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol induced apoptotic cell death in a dose dependent manner (0-15 μg/ml) through activation of Fas and death receptor (DR) 3 in HCT116 and SW480 colon cancer cell lines. Moreover, the combination treatment with (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol and nuclear factor κB (NF-κB) inhibitor, phenylarsine oxide (0.1 μM) or signal transducer and activator of transcription 3 (STAT3) inhibitor, Stattic (50 μM) increased the expression of Fas and DR3 more significantly. In addition, (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol suppressed the DNA binding activity of both STAT3 and NF-κB. Knock down of STAT3 or NF-κB p50 subunit by STAT3 small interfering RNA (siRNA) or p50 siRNA magnified (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol-induced inhibitory effect on colon cancer cell growth. Besides, the expression of Fas and DR3 was increased in STAT3 siRNA or p50 siRNA transfected cells. Moreover, docking model and pull-down assay showed that (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol directly bound to STAT3 and NF-κB p50 subunit. Furthermore, (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol inhibited colon tumor growth in a dose dependent manner (2.5 mg/kg-5 mg/kg) in mice. Therefore, these findings indicated that (E)-4-(3-(3,5-dimethoxyphenyl)allyl)-2-methoxyphenol may be a promising anti-cancer agent for colon cancer with more advanced research. PMID

  8. 1,1',4,5-tetrahydrotrispiro[1,3,2-diazaphosphole-2,2'-[1,3,5,2,4,6]triazatriphosphinine-4',6''-dibenzo[d,f][1,3,2]dioxaphosphepine-6',6'''-dibenzo[d,f][1,3,2]dioxaphosphepine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The title compound 1,1',4,5-tetrahydrotrispiro[1,3,2-diazaphosphole-2,2'-[1,3,5,2,4,6]triazatriphosphinine-4',6''-dibenzo[d,f][1,3,2]dioxaphosphepine-6',6'''-dibenzo[d,f][1,3,2]dioxaphosphepine], C26H22N5O4P3, at 100°K has monoclinic (P21/c) symmetry and is achieved in a two step synthesis that does...

  9. Synthesis and biological activity of hydrazide hydrazones and their corresponding 3-acetyl-2,5-disubstituted-2,3-dihydro-1,3,4-oxadiazoles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Various new 3-acetyl-2,5-disubstituted-2,3-dihydro-1,3,4-oxadiazoles (11-20) were prepared by the reaction of aryl substituted hydrazones of 4-fluorobenzoic acid hydrazide (1-10) with acetic anhydride. The structures of the newly synthesized compounds 11-20, were confirmed by UV, IR and 1H NMR spec...

  10. Application of V2O5/WO3/TiO2 for Resistive-Type SO2 Sensors

    PubMed Central

    Izu, Noriya; Hagen, Gunter; Schönauer, Daniela; Röder-Roith, Ulla; Moos, Ralf

    2011-01-01

    A study on the application of V2O5/WO3/TiO2 (VWT) as the sensitive material for resistive-type SO2 sensor was conducted, based on the fact that VWT is a well-known catalyst material for good selective catalytic nitrogen oxide reduction with a proven excellent durability in exhaust gases. The sensors fabricated in this study are planar ones with interdigitated electrodes of Au or Pt. The vanadium content of the utilized VWT is 1.5 or 3.0 wt%. The resistance of VWT decreases with an increasing SO2 concentration in the range from 20 ppm to 5,000 ppm. The best sensor response to SO2 occurs at 400 °C using Au electrodes. The sensor response value is independent on the amount of added vanadium but dependent on the electrode materials at 400 °C. These results are discussed and a sensing mechanism is discussed. PMID:22163780

  11. Thiazyl Trifluoride (NSF3) Adducts and Imidodifluorosulfate (F2OSN-) Derivatives of Hg(OTeF5)2.

    PubMed

    DeBackere, John R; Mercier, Hélène P A; Schrobilgen, Gary J

    2015-10-19

    Reactions of Hg(OTeF5)2 with excess amounts of NSF3 at 0 °C result in the formation of NSF3 adducts having the compositions [Hg(OTeF5)2·N≡SF3]∞ (1), [Hg(OTeF5)2·2N≡SF3]2 (2), and Hg3(OTeF5)6·4N≡SF3 (3). When the reactions are carried out at room temperature, oxygen/fluorine metatheses occur yielding the F2OSN- derivatives [Hg(OTeF5)(N═SOF2)·N≡SF3]∞ (4) and [Hg3(OTeF5)5(N═SOF22N≡SF3]2 (5). The proposed reaction pathway leading to F2OSN- group formation occurs by nucleophilic attack by a F5TeO- group at the sulfur(VI) atom of NSF3, followed by TeF6 elimination. Tellurium hexafluoride formation was confirmed by (19)F NMR spectroscopy. The NSF3 molecules are terminally N-coordinated to mercury, whereas the F2OSN- ligands are N-bridged to two mercury atoms. The compound series was characterized by low-temperature single-crystal X-ray diffraction and low-temperature Raman spectroscopy. Several structural motifs are observed within this structurally diverse series. These include the infinite chain structures of the related compounds, 1 and 4; 2, a dimeric structure which possesses an (HgO(μ))2 ring at its core; 3, a structure based on a cage comprised of a (HgO(μ))3 ring that is capped on each face by μ(3)-oxygen bridged F5TeO- groups; and 5, a dimeric structure possessing two distorted (Hg3O2N) rings that are formally derived from 3 by replacement of a F5TeO- group by a F2OSN- group in each ring. Quantum-chemical calculations were carried out to gain insight into the bonding of the μ(3)-oxygen bridged teflate groups observed in structure 3. Compounds 1-5 represent a novel class of neutral transition metal complexes with NSF3, providing the first examples of NSF3 coordination to mercury. Compounds 4 and 5 also provide the only examples of F2OSN- derivatives of mercury that have been characterized by single-crystal X-ray diffraction. PMID:26413855

  12. Application of the Novel 5-chloro-2,2,3,3,4,4,5,5-octafluoro-1-pentyl Chloroformate Derivatizing Agent for the Direct Determination of Highly Polar Water Disinfection Byproducts

    EPA Science Inventory

    A novel derivatizing agent, 5-chloro-2,2,3,3,4,4,5,5-octafluoropentyl chloroformate (ClOFPCF), was synthesized and tested as a reagent for direct water derivatization of highly polar and hydrophilic analytes. Its analytical performance satisfactorily compared to a perfluorinated ...

  13. Synthesis, solvatochromism and crystal structure of 5-Methoxy-5,6-diphenyl-4,5-dihydro-2H −1,2,4-triazine-3-thione

    PubMed Central

    2013-01-01

    Background For the development of properties in molecular crystals, such as electrical conductivities, magnetic properties, or non-linear optical properties, not only the electronic properties of molecules themselves matter, but also the molecular arrangements in the crystals are very important. Therefore, the design of the crystal structures and the control of molecular arrangements have attracted much attention in recent years. Among various ligands, triazine moieties have been especially interesting because of their biological, pharmacological and medicinal properties. Results Crystal structure of 5-Methoxy-5,6-diphenyl-4,5-dihydro-2H-1,2,4-triazine-3-thione is Monoclinic, which consists of space group P21/c with a = 9.699(1), b = 8.500(1), c = 18.044(2) Å, β = 101.290(7)° and Z = 4, R1 = 0.0371 and wR2 = 0.1008 with 2456 reflections (I > 2σ(I)). Intermolecular H bonds between NH groups are acting as donors and S atoms as acceptors. There are also shorted face-to-face as well as edge to face π-π stacking interactions between the parallel aromatic rings. The behavior of solvatochromic of the mentioned compound that involved interhydrogen bonding was investigated by studying its electronic absorption spectra in pure organic solvents of different characters. Conclusions The crystal structure of C16H15N3OS, shows the expected face-to-face π-π stacking interactions between aromatic rings of the neighbor chains in this compound. The centroid–centroid distance between the aromatic rings is 3.325 Å. It was found that the monomer of the ligand 5-Methoxy-5,6-diphenyl-4,5-dihydro-2H-1,2,4-triazine-3-thione, further extends into 3D networks via hydrogen bonding and pi-pi stacking interactions. The solvatochromic behavior of the title compound was also investigated by studying its spectra in a selection of different organic solvents. While progressing from the non-polar solvent to the polar one, the main intense band at 310

  14. Synthesis, structural and computational characterization of 2-amino-3,5-diiodobenzoic acid and 2-amino-3,5-dibromobenzoic acid

    NASA Astrophysics Data System (ADS)

    Yıldırım, M. Hakkı; Paşaoğlu, Hümeyra; Odabaşoğlu, Hakkı Yasin; Odabaşoğlu, Mustafa; Yıldırım, Arzu Özek

    2015-07-01

    The benzoic acid compounds 2-amino-3,5-dibromobenzoic acid (2A35Br) and 2-amino-3,5-diiodobenzoic (2A35I) acid have been synthesized and characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, UV-Vis spectroscopy and computational methods. Molecular geometry, intra- and inter-molecular interactions have been investigated by using X-ray diffraction technique. Fundamental vibrational bands of the title compounds were founded by FT-IR and UV-Vis method was used to obtain electronic bands. Geometry optimizations and the calculation of IR frequencies were performed both Gaussian type orbitals at Gaussian 09W and Slater type orbitals at ADF2009.01 software. The calculations are compatible with the experiment results. In addition, geometrical parameters, energies, HOMO-LUMO gaps and electrophilicity indexes have been calculated for thirty possible positional isomers of 2A35Br and 2A35I. Calculations show that 2A35Br and 2A35I isomers have the lowest energy, the narrowest HOMO-LUMO gap and the highest electrophilicity index values. Molecular electrostatic potential maps, Fukui indices, natural bond orbital analysis, thermodynamic parameters and non-linear optical properties of the 2A35Br and 2A35I were also investigated by theoretical calculations.

  15. Conformational Changes in Inositol 1,3,4,5,6-Pentakisphosphate 2-Kinase upon Substrate Binding

    PubMed Central

    Baños-Sanz, José Ignacio; Sanz-Aparicio, Julia; Whitfield, Hayley; Hamilton, Chris; Brearley, Charles A.; González, Beatriz

    2012-01-01

    Inositol 1,3,4,5,6-pentakisphosphate 2-kinase (IP5 2-K) catalyzes the synthesis of inositol 1,2,3,4,5,6-hexakisphosphate from ATP and IP5. Inositol 1,2,3,4,5,6-hexakisphosphate is implicated in crucial processes such as mRNA export, DNA editing, and phosphorus storage in plants. We previously solved the first structure of an IP5 2-K, which shed light on aspects of substrate recognition. However, failure of IP5 2-K to crystallize in the absence of inositide prompted us to study putative conformational changes upon substrate binding. We have made mutations to residues on a region of the protein that produces a clasp over the active site. A W129A mutant allowed us to capture IP5 2-K in its different conformations by crystallography. Thus, the IP5 2-K apo-form structure displays an open conformation, whereas the nucleotide-bound form shows a half-closed conformation, in contrast to the inositide-bound form obtained previously in a closed conformation. Both nucleotide and inositide binding produce large conformational changes that can be understood as two rigid domain movements, although local changes were also observed. Changes in intrinsic fluorescence upon nucleotide and inositide binding are in agreement with the crystallographic findings. Our work suggests that the clasp might be involved in enzyme kinetics, with the N-terminal lobe being essential for inositide binding and subsequent conformational changes. We also show how IP5 2-K discriminates between inositol 1,3,4,5-tetrakisphosphate and 3,4,5,6-tetrakisphosphate enantiomers and that substrate preference can be manipulated by Arg130 mutation. Altogether, these results provide a framework for rational design of specific inhibitors with potential applications as biological tools for in vivo studies, which could assist in the identification of novel roles for IP5 2-K in mammals. PMID:22745128

  16. Fluorine for Hydrogen Exchange in the Hydrofluorobenzene Derivatives C6HxF(6-x), where x = 2, 3, 4 and 5 by Monomeric [1,2,4-(Me3C)3C5H2]2CeH; The Solid State Isomerization of [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,5-C6HF4) to [1,2,4-(Me3C)3C5H2]2Ce(2,3,4,6-C6HF4)

    SciTech Connect

    Andersen, Richard; Werkema, Evan L.; Andersen, Richard A.

    2008-04-21

    The reaction between monomeric bis(1,2,4-tri-t-butylcyclopentadienyl)cerium hydride, Cp'2CeH, and several hydrofluorobenzene derivatives is described. The aryl derivatives that are the primary products, Cp'2Ce(C6H5-xFx) where x = 1,2,3,4, are thermally stable enough to be isolated in only two cases, since all of them decompose at different rates to Cp'2CeF and a fluorobenzyne; the latter is trapped by either solvent when C6D6 is used or by a Cp'H ring when C6D12 is the solvent. The trapped products are identified by GCMS analysis after hydrolysis. The aryl derivatives are generated cleanly by reaction of the metallacycle, Cp'((Me3C)2C5H2C(Me2)CH2)Ce, with a hydrofluorobenzene and the resulting arylcerium products, in each case, are identified by their 1H and 19F NMR spectra at 20oC. The stereochemical principle that evolves from these studies is that the thermodynamic isomer is the one in which the CeC bond is flanked by two ortho-CF bonds. This orientation is suggested to arise from the negative charge that is localized on the ipso-carbon atom due to Co(delta+)-Fo(delta-) polarization. The preferred regioisomer is determined by thermodynamic rather than kinetic effects; this is illustrated by the quantitative, irreversible solid-state conversion at 25oC over two months of Cp'2Ce(2,3,4,5-C6HF4) to Cp'2Ce(2,3,4,6-C6HF4), an isomerization that involves a CeC(ipso) for C(ortho)F site exchange.

  17. [(CF3)4Au2(C5H5N)2]--a new alkyl gold(II) derivative with a very short Au-Au bond.

    PubMed

    Zopes, David; Hegemann, Corinna; Tyrra, Wieland; Mathur, Sanjay

    2012-09-11

    A new gold(II) species [(CF(3))(4)Au(2)(C(5)H(5)N)(2)] with a very short unsupported Au-Au bond (250.62(9) pm) was generated by photo irradiation of a silver aurate, [Ag(Py)(2)][Au(CF(3))(2)], unambiguously characterized by (19)F and (109)Ag NMR studies. PMID:22836874

  18. High-pressure laser spectroscopy of Cr3+:Gd3Sc2Ga3O12 and Cr3+:Gd3Ga5O12

    NASA Astrophysics Data System (ADS)

    Hömmerich, U.; Bray, K. L.

    1995-05-01

    We report on the effect of high pressure on the room-temperature emission spectra and lifetimes of Cr3+:GSGG (Gd3Sc2Ga3O12) and Cr3+:GGG (Gd3Ga5O12). In both systems we observed a dramatic change of the overall emission band shape upon increasing pressure, from a nearly structureless broadband (4T2-->4A2) to a highly structured narrow band (2E-->4A2). From the peak energy of the broadband emission, we estimated the pressure-induced blueshift of the 4T2-->4A2 transition to be 10 (+/-2) cm-1/kbar. High-resolution measurements in the R-line region (~700 nm) revealed that the 2E-->4A2 transition hardly shifts at low pressures (<40 kbar), whereas at higher pressures (>60 kbar) a nearly linear redshift of 0.65 (+/-0.05) cm-1/kbar is observed. Besides pressure-induced spectral changes, an enormous increase in the emission lifetime with increasing pressure was found for both systems. In the case of Cr3+:GSGG, the lifetime changed from 110 μs at ambient pressure to 4.4 ms at 125 kbar. For Cr3+:GGG, the lifetime increased from 168 μs to 7.3 ms for the same pressure range. The pressure-induced spectral and lifetime changes are described by a single configurational coordinate model that considers the effect of pressure on the thermal and spin-orbit coupling of the 2E and 4T2 states. A previously reported pressure-induced R-line-shift reversal in Cr3+:GSGG and the effect of high pressure on the lifetime in Cr3+:YAG are also discussed within the same framework.

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

    EPA Science Inventory

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

  20. Structure and dielectric dispersion in cubic-like 0.5K0.5Na0.5NbO3-0.5Na1/2Bi1/2TiO3 ceramic

    NASA Astrophysics Data System (ADS)

    Liu, Laijun; Knapp, Michael; Schmitt, Ljubomira Ana; Ehrenberg, Helmut; Fang, Liang; Fuess, Hartmut; Hoelzel, Markus; Hinterstein, Manuel

    2016-05-01

    The nature of the cubic-like state in the lead-free piezoelectric ceramics 0.5K0.5Na0.5NbO3-0.5Na1/2Bi1/2TiO3 (KNN-50BNT) has been examined in detail by synchrotron x-ray diffraction (SD), selected-area electron diffraction (SAED), neutron diffraction (ND), and temperature-dependent dielectric characterization. The SD pattern of KNN-50BNT presents a pure perovskite structure with pseudocubic symmetry. However, superlattice reflections were observed by SAED and completely indexed by tetragonal symmetry with P4bm space group in ND pattern. The relaxor behavior of KNN-50BNT is compared with Pb-based and Ba-based relaxors and discussed in the framework of the Vogel-Fulcher law and the new glass model. The KNN-50BNT ceramic exhibits the strongest dielectric dispersion among them.

  1. Crystal and molecular structure of the coordination compounds of Er{sup 3+} with 1-(methoxydiphenylphosphoryl)-2-diphenylphosphorylbenzene [ErL{sub 2}{sup 1}(NO{sub 3}){sub 2}]{sub 2}[Er(NO{sub 3}){sub 2}(H{sub 2}O){sub 5}]{sub 0.333}(NO{sub 3}){sub 2.333} · 2.833H{sub 2}O and its ethyl substituted derivative [ErL{sub 2}{sup 2}(NO{sub 3}){sub 2}][Er(NO{sub 3}){sub 5}]{sub 0.5} · 0.5H{sub 2}O

    SciTech Connect

    Polyakova, I. N.; Baulin, V. E.; Ivanova, I. S.; Pyatova, E. N.; Sergienko, V. S.; Tsivadze, A. Yu.

    2015-01-15

    The coordination compounds of Er{sup 3+} with 1-(methoxydiphenylphosphoryl)-2-diphenylphosphorylbenzene [ErL{sub 2}{sup 1}(NO{sub 3}){sub 2}]{sub 2}[Er(NO{sub 3}){sub 2}(H{sub 2}O){sub 5}]{sub 0.333}(NO{sub 3}){sub 2.333} · 2.833H{sub 2}O (I) and its ethyl substituted derivative [ErL{sub 2}{sup 2}(NO{sub 3}){sub 2}][Er(NO{sub 3}){sub 5}]{sub 0.5} · 0.5H{sub 2}O (II) are synthesized and their crystal structures are studied. I and II contain [ErL{sub 2}(NO{sub 3}){sub 2}]{sup +} complex cations of identical composition and close structure. The eight-vertex polyhedron of the Er atom in the shape of a distorted octahedron with two split trans vertices is formed by the O atoms of the phosphoryl groups of L ligands and nitrate anions. L ligands close nine-membered metallocycles. The structures contain spacious channels which are populated differently, namely, by disordered [Er(NO{sub 3}){sub 2}(H{sub 2}O){sub 5}]{sup +} complex cations, NO{sub 3}{sup −} anions, and crystallization water molecules in I and disordered [Er(NO{sub 3}){sub 5}]{sup 2−} complex anions and crystallization water molecules in II. The IR spectra of I and II are studied.

  2. Fluorescent and nonfluorescent crystals of N-(3,5-dihalogenosalicylidene)-2-methoxyaniline

    NASA Astrophysics Data System (ADS)

    Tsuchimoto, Masanobu; Yoshida, Narihiro; Sugimoto, Atsuki; Teramoto, Naozumi; Nakajima, Kiyohiko

    2016-02-01

    Crystals of N-(3,5-diXsalicylidene)-2-methoxyaniline (X = fluoro, chloro, bromo, and iodo) were prepared, and their structural and luminescence properties in the solid state were investigated. Only fluorescent orange crystals were obtained for N-(3,5-difluorosalicylidene)-2-methoxyaniline (1). Both fluorescent orange crystals (2a) and nonfluorescent red-orange crystals (2b) were obtained for N-(3,5-dichlorosalicylidene)-2-methoxyaniline. Slightly fluorescent orange crystals were obtained for N-(3,5-dibromosalicylidene)-2-methoxyaniline (3) and N-(3,5-diiodosalicylidene)-2-methoxyaniline (4). Fluorescence spectra of 1, 2a, 3, and 4 in the solid state show a fluorescence band at around 600 nm by excitation at 480 nm. The fluorescence intensities were in the order 1 > 2a > 3 > 4. X-ray crystal-structure analyses of 1, 2a, and 2b were obtained. The N-salicylideneaniline molecules in all of the crystals have planar structures. The molecules in both 1 and 2b take the enol form, while the molecules in 2a take the cis-keto form. The crystals 2a include water of crystallization, which is hydrogen bonded to the adjacent N-salicylideneaniline molecules. Molecules in fluorescent 2a are arranged in stacks along the a-axis to form a columnar structure in the crystals. In contrast, molecules in nonfluorescent 2b are strongly π-π stacked to form dimers in crystals. The orange crystals 2a were transformed to the red-orange crystals 2b by removal of water of crystallization upon heating at 70 °C.

  3. Synthesis, crystal structures and theoretical calculations of new 1-[2-(5-chloro-2-benzoxazolinone-3-yl)acetyl]-3,5-diphenyl-4,5-dihydro-(1H)-pyrazoles

    NASA Astrophysics Data System (ADS)

    Gökşen, Umut Salgın; Alpaslan, Yelda Bingöl; Kelekçi, Nesrin Gökhan; Işık, Şamil; Ekizoğlu, Melike

    2013-05-01

    1-[2-(5-Chloro-2-benzoxazolinone-3-yl)acetyl]-3-phenyl-5-(3-methoxyphenyl)-4,5-dihydro-(1H)-pyrazole (5a), 1-[2-(5-chloro-2-benzoxazolinone-3-yl)acetyl]-3-phenyl-5-(3,4-dimethoxyphenyl)-4,5-dihydro-(1H)-pyrazole (5b) and 1-[2-(5-chloro-2-benzoxazolinone-3-yl)acetyl]-3-(4-methylphenyl)-5-(2,3-dimethoxyphenyl)-4,5-dihydro-(1H)-pyrazole (5c) were synthesized. The crystal and molecular structures of the compounds 5a, 5b and 5c were determined by elemental analyses, IR, 1H NMR, ESI-MS and single-crystal X-ray diffraction. DFT method with 6-31G(d,p) basis set was used to calculate the optimized geometrical parameters, vibrational frequencies and chemical shift values. The calculated vibrational frequencies and chemical shift values were compared with experimental IR and 1H NMR values. The results represented that there was a good agreement between experimental and calculated values of the compounds 5a-5c. In addition, DFT calculations of the compounds, molecular electrostatic potentials (MEPs) and frontier molecular orbitals were performed at B3LYP/6-31G(d,p) level of theory. Furthermore, compounds were tested against three Gram-positive bacteria: Staphylococcus aureus ATCC 29213 (American Type Culture Collection), methicillin resistant S. aureus (MRSA) ATCC 43300 and Enterococcus faecalis ATCC 29212; two Gram negative bacteria: Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853; and three fungi: Candida albicans ATCC 90028, Candida krusei ATCC 6258 and Candida parapsilosis ATCC 90018. In general, all of the compounds were found to be slightly active against tested microorganisms.

  4. Synthesis, characterization, and crystal structure of 2-amino-5-oxo-4-phenyl-4,5-dihydropyrano[3,2- c]chromene-3-carbonitrile

    NASA Astrophysics Data System (ADS)

    Sharma, S.; Brahmachari, G.; Banerjee, B.; Kant, R.; Gupta, V. K.

    2015-12-01

    The title compound, 2-amino-5-oxo-4-phenyl-4,5-dihydropyrano[3,2- c]chromene-3-carbonitrile was synthesized in excellent yield by one-pot multicomponent reaction and its crystal structure is determined by X-ray structure analysis. The crystals are monoclinic, sp. gr. P21/ c, a = 9.0750(6), b = 13.2729(8), c = 12.6892(9) Å, β = 96.975(6)°, Z = 4; R = 0.0466 for 1771 observed reflections. The crystal structure is stabilized by N-H···N, N-H···O and C-H···O hydrogen bonds. In addition, C-H···π and π···π interactions are observed in the crystal structure.

  5. 1,3,2,5-Diazadiborinine featuring nucleophilic and electrophilic boron centres.

    PubMed

    Wu, Di; Kong, Lingbing; Li, Yongxin; Ganguly, Rakesh; Kinjo, Rei

    2015-01-01

    The seminal discovery in 1865 by Kekulé that benzene nucleus exists with cyclic skeleton is considered to be the beginning of aromatic chemistry. Since then, a myriad of cyclic molecules displaying aromatic property have been synthesized. Meanwhile, borazine (B3N3H6), despite the isostructural and isoelectronic relationships with benzene, exhibits little aromaticity. Herein, we report the synthesis of a 1,3,2,5-diazadiborinine (B2C2N2R6) derivative, a hybrid inorganic/organic benzene, and we present experimental and computational evidence for its aromaticity. In marked contrast to the reactivity of benzene, borazine, and even azaborinines previously reported, 1,3,2,5-diazadiborinine readily forms the adducts with methyl trifluoromethanesulfonate and phenylacetylene without any catalysts. Moreover, 1,3,2,5-diazadiborine activates carbon dioxide giving rise to a bicycle[2,2,2] product, and the binding process was found to be reversible. These results, thus, demonstrate that 1,3,2,5-diazadiborinine features both nucleophilic and electrophilic boron centres, with a formal B(+I)/B(+III) mixed valence system, in the aromatic six-membered B2C2N2 ring. PMID:26073993

  6. 1,3,2,5-Diazadiborinine featuring nucleophilic and electrophilic boron centres

    PubMed Central

    Wu, Di; Kong, Lingbing; Li, Yongxin; Ganguly, Rakesh; Kinjo, Rei

    2015-01-01

    The seminal discovery in 1865 by Kekulé that benzene nucleus exists with cyclic skeleton is considered to be the beginning of aromatic chemistry. Since then, a myriad of cyclic molecules displaying aromatic property have been synthesized. Meanwhile, borazine (B3N3H6), despite the isostructural and isoelectronic relationships with benzene, exhibits little aromaticity. Herein, we report the synthesis of a 1,3,2,5-diazadiborinine (B2C2N2R6) derivative, a hybrid inorganic/organic benzene, and we present experimental and computational evidence for its aromaticity. In marked contrast to the reactivity of benzene, borazine, and even azaborinines previously reported, 1,3,2,5-diazadiborinine readily forms the adducts with methyl trifluoromethanesulfonate and phenylacetylene without any catalysts. Moreover, 1,3,2,5-diazadiborine activates carbon dioxide giving rise to a bicycle[2,2,2] product, and the binding process was found to be reversible. These results, thus, demonstrate that 1,3,2,5-diazadiborinine features both nucleophilic and electrophilic boron centres, with a formal B(+I)/B(+III) mixed valence system, in the aromatic six-membered B2C2N2 ring. PMID:26073993

  7. In situ synthesis and hardness of TiC/Ti5Si3 composites on Ti-5Al-2.5Sn substrates by gas tungsten arc welding

    NASA Astrophysics Data System (ADS)

    Yan, Wen-qing; Dai, Le; Gui, Chi-bin

    2013-03-01

    TiC/Ti5Si3 composites were fabricated on Ti-5Al-2.5Sn substrates by gas tungsten arc welding (GTAW). Identification of the phases was performed using X-ray diffraction (XRD). The microstructures were analyzed using scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectrometry (EDS) and optical microscopy (OM). The Vickers hardness was measured with a micro-hardness tester. The TiC/Ti5Si3 composites were obtained in a double-layer track, and the Vickers hardness of the track increased by two to three times compared with the Ti-5Al-2.5Sn substrate.

  8. Tunable emission, energy transfer and charge compensation in Sr3(VO4)2:Sm(3+),P(5+),Na(+) phosphor.

    PubMed

    Cao, Renping; Peng, Dedong; Xu, Haidong; Jiang, Shenhua; Fu, Ting; Luo, Wenjie; Luo, Zhiyang

    2015-11-01

    A series of Sr3(VO4)2:Sm(3+),P(5+),Na(+) phosphors are synthesized by using solid-state reaction method in air. The strongest emission band peaking at ∼600 nm is assigned to the (4)G5/2→(6)H7/2 transition of Sm(3+) ion, and the strong excitation peak at ∼402 nm due to (6)H5/2→(4)F7/2 transition indicates that these phosphors can be excited by near ultraviolet light emitting diode chip. Energy transfer (ET) between VO4(3-) group and Sm(3+) ion can be observed. Sr3(VO4)2:Sm(3+) phosphor with excitation 320 nm exhibits a systematically varied hues from green to yellow by changing Sm(3+) ion concentration from 0 to 6 mol%. The luminous mechanism of Sr3(VO4)2:Sm(3+) phosphor is explained by using the energy level diagrams of VO4(3-) group and Sm(3+) ion. The luminescence properties of Sr3(VO4)2:Sm(3+) phosphor can be improved and tuned by codoping the P(5+) and Na(+) ions due to ET and charge compensation. Lifetimes of Sr2.925Sm0.05(VO4)2, Sr2.925Sm0.05(V0.9P0.1O4)2, and Sr2.9Na0.05Sm0.05(V0.9P0.1O4)2 phosphors are 1.208, 1.219, and 0.796 ms, respectively. The experiment results are helpful to adjust the luminescence properties of Sm(3+)-doped other phosphors. PMID:26067936

  9. PREPARATION, CHARACTERIZATION AND ACTIVITY OF AL2O3-SUPPORTED V2O5 CATALYSTS

    EPA Science Inventory

    A series of activated alumina supported vanadium oxide catalysts with various V2O5 loadings ranging from 5 to 25 wt% has been prepared by wet impregnation technique. A combination of various physico-chemical techniques such as BET surface areas, oxygen chemisorption, X-ray diffra...

  10. Functional expression of 5-HT{sub 2A} receptor in osteoblastic MC3T3-E1 cells

    SciTech Connect

    Hirai, Takao; Kaneshige, Kota; Kurosaki, Teruko; Nishio, Hiroaki

    2010-05-28

    In the previous study, we reported the gene expression for proteins related to the function of 5-hydroxytryptamine (5-HT, serotonin) and elucidated the expression patterns of 5-HT{sub 2} receptor subtypes in mouse osteoblasts. In the present study, we evaluated the possible involvement of 5-HT receptor subtypes and its inactivation system in MC3T3-E1 cells, an osteoblast cell line. DOI, a 5-HT{sub 2A} and 5-HT{sub 2C} receptor selective agonist, as well as 5-HT concentration-dependently increased proliferative activities of MC3T3-E1 cells in their premature period. This effect of 5-HT on cell proliferation were inhibited by ketanserin, a 5-HT{sub 2A} receptor specific antagonist. Moreover, both DOI-induced cell proliferation and phosphorylation of ERK1 and 2 proteins were inhibited by PD98059 and U0126, selective inhibitors of MEK in a concentration-dependent manner. Furthermore, treatment with fluoxetine, a 5-HT specific re-uptake inhibitor which inactivate the function of extracellular 5-HT, significantly increased the proliferative activities of MC3T3-E1 cells in a concentration-dependent manner. Our data indicate that 5-HT fill the role for proliferation of osteoblast cells in their premature period. Notably, 5-HT{sub 2A} receptor may be functionally expressed to regulate mechanisms underlying osteoblast cell proliferation, at least in part, through activation of ERK/MAPK pathways in MC3T3-E1 cells.

  11. Syntheses and Promising Properties of Dense Energetic 5,5'-Dinitramino-3,3'-azo-1,2,4-oxadiazole and Its Salts.

    PubMed

    Tang, Yongxing; Gao, Haixiang; Mitchell, Lauren A; Parrish, Damon A; Shreeve, Jean'ne M

    2016-02-24

    A planar energetic molecule with high density, 5,5'-dinitramino-3,3'-azo-1,2,4-oxadiazole (4), was obtained by the nitration of 5,5'-diamino-3,3'-azo-1,2,4-oxadiazole using 100 % nitric acid. In addition, selected nitrogen-rich salts were prepared. Of them, the neutral compound 4 and its hydroxylammonium salt, 6, were further confirmed by single-crystal X-ray diffraction. Physicochemical and energetic properties including density, thermal stability, and sensitivity were investigated. The energetic performance from the calculated heats of formation and experimental densities indicates that many of them have potential applications as energetic materials. PMID:26822007

  12. Preparation of 7-hydroxy-2-oxoindolin-3-ylacetic acid and its [13C2], [5-n-3H], and [5-n-3H]-7-O-glucosyl analogues for use in the study of indol-3-ylacetic acid catabolism

    NASA Technical Reports Server (NTRS)

    Lewer, P.; Bandurski, R. S. (Principal Investigator)

    1987-01-01

    An improved synthesis of 7-hydroxy-2-oxoindolin-3-ylacetic acid via the base-induced condensation reaction between oxalate esters and 7-benzyloxyindolin-2-one is described. 7-Benzyloxyindolin-2-one was prepared in four steps and 50% overall yield from 3-hydroxy-2-nitrotoluene. The yield of the title compound from 7-benzyloxyindolin-2-one was 56%. This route was used to prepare 7-hydroxy-2-oxoindolin-3-yl[13C2]acetic acid in 30% yield from [13C2]oxalic acid dihydrate. The method could not be extended to the preparation of the corresponding [14C2]-compound. However, an enzyme preparation from Zea mays roots catalysed the conversion of carrier-free [5-n-3H]indol-3-ylacetic acid with a specific activity of 16.7 Ci mmol-1 to a mixture of 7-hydroxy-2-oxo[5-n-3H]indolin-3-ylacetic acid and its [5-n-3H]-7-O-glucoside in ca. 3 and 40% radiochemical yield respectively. The glucoside was converted into the 7-hydroxy compound in 80% yield by means of beta-glucosidase.

  13. The ML1Nx2 Phosphatidylinositol 3,5-Bisphosphate Probe Shows Poor Selectivity in Cells

    PubMed Central

    Hammond, Gerald R. V.; Takasuga, Shunsuke; Sasaki, Takehiko; Balla, Tamas

    2015-01-01

    Phosphatidylinositol (3,5)-bisphosphate (PtdIns(3,5)P2) is a quantitatively minor phospholipid in eukaryotic cells that plays a fundamental role in regulating endocytic membrane traffic. Despite its clear importance for cellular function and organism physiology, mechanistic details of its biology have so far not been fully elucidated. In part, this is due to a lack of experimental tools that specifically probe for PtdIns(3,5)P2 in cells to unambiguously identify its dynamics and site(s) of action. In this study, we have evaluated a recently reported PtdIns(3,5)P2 biosensor, GFP-ML1Nx2, for its veracity as such a probe. We report that, in live cells, the localization of this biosensor to sub-cellular compartments is largely independent of PtdIns(3,5)P2, as assessed after pharmacological, chemical genetic or genomic interventions that block the lipid’s synthesis. We therefore conclude that it is unwise to interpret the localization of ML1Nx2 as a true and unbiased biosensor for PtdIns(3,5)P2. PMID:26460749

  14. The Reaction of DABCO with 4-Chloro-5H-1,2,3-dithiazoles: Synthesis and Chemistry of 4-[N-(2-Chloroethyl)piperazin-1-yl]-5H-1,2,3-dithiazoles.

    PubMed

    Koyioni, Maria; Manoli, Maria; Koutentis, Panayiotis A

    2016-01-15

    N-(4-Chloro-5H-1,2,3-dithiazol-5-ylidene)anilines react with DABCO in hot PhCl to give N-{4-[N-(2-chloroethyl)piperazin-1-yl]-5H-1,2,3-dithiazol-5-ylidene}anilines in high yields (70-92%). The reaction also works with 4-chloro-5H-1,2,3-dithiazol-5-one and -thione, giving the corresponding products in 85% and 76% yields, respectively. While the reaction of several (4-chloro-5H-1,2,3-dithiazol-5-ylidene)methanes with DABCO failed to give {4-[N-(2-chloroethyl)piperazin-1-yl]-5H-1,2,3-dithiazol-5-ylidene}methanes, these can be prepared in moderate yields via classical cycloaddition-retrocycloaddition strategies from 4-[N-(2-chloroethyl)piperazin-1-yl]-5H-1,2,3-dithiazole-5-thione. The 2-chloroethyl moiety on selected dithiazoles was also modified without cleavage of the 1,2,3-dithiazole by reaction with various nucleophiles, giving access to 4-[N-(2-substituted)piperazin-1-yl]-5H-1,2,3-dithiazoles in moderate to high yields. PMID:26671065

  15. Analysis of the Rotational Spectra of 2,3,4,5,6-PENTAFLUOROTOLUENE and 1-CHLORO-2,3,4,5,6-PENTAFLUOROBENZENE

    NASA Astrophysics Data System (ADS)

    Osthoff, Ashley A.; Peebles, Rebecca A.; Peebles, Sean A.; Grubbs, Garry S. Grubbs, II; Cooke, Stephen A.; Pate, Brooks H.; Neill, Justin L.; Muckle, Matt T.

    2009-06-01

    The microwave spectra of two substituted pentafluorobenzenes have been obtained. 2,3,4,5,6-Pentafluorotoluene was measured using the FTMW spectrometer at Eastern Illinois University and the chirped-pulse FTMW spectrometer at University of North Texas. The heavy atom structure has been obtained from the assigned ^{13}C transitions and is in reasonable agreement with ab initio calculations at the MP2/6-311++G(2d, 2p) level. The ground state rotational constants are A = 1036.61253(10) MHz, B = 1030.94126(10) MHz, and C = 516.92062(9) MHz, and the single dipole moment component is μ_b = 1.98(17) D. Very small splittings for many of the assigned transitions and multiple, as yet unassigned, lines were presumably due to excited torsional states of the methyl group. In a related study, the microwave spectrum of 1-chloro-2,3,4,5,6-pentafluorobenzene was obtained for both the ^{35}Cl and the ^{37}Cl isotopologues using the chirped-pulse microwave spectrometer at University of Virginia. The preliminary ground state rotational constants for this compound are A = 1028.5403(14) MHz, B = 751.8198(3) MHz and C = 434.3533(4) MHz for ^{35}Cl and A = 1028.5435(7) MHz, B = 734.4786(2) MHz and C = 428.5082(2) MHz for ^{37}Cl. Initial fits of the nuclear quadrupole coupling constants give χ_{aa} = -79.512(15) MHz, χ_{bb} = 43.593(8) MHz, χ_{cc} = 35.92(2) MHz for the ^{35}Cl species and χ_{aa} = -62.68(2) MHz, χ_{bb} = 34.38(4) MHz, χ_{cc} = 28.29(17) MHz for the ^{37}Cl species. These results will be compared with pentafluorotoluene to observe the effects on the structure of the benzene ring when substituting a chlorine atom for a methyl group.

  16. 2D→3D polycatenated and 3D→3D interpenetrated metal–organic frameworks constructed from thiophene-2,5-dicarboxylate and rigid bis(imidazole) ligands

    SciTech Connect

    Erer, Hakan; Yeşilel, Okan Zafer; Arıcı, Mürsel; Keskin, Seda; Büyükgüngör, Orhan

    2014-02-15

    Hydrothermal reactions of rigid 1,4-bis(imidazol-1-yl)benzene (dib) and 1,4-bis(imidazol-1-yl)-2,5-dimethylbenzene (dimb) with deprotonated thiophene-2,5-dicarboxylic acid (H{sub 2}tdc) in the presence of Zn(II) and Cd(II) salts in H{sub 2}O produced three new metal–organic frameworks, namely, [Zn(µ-tdc)(H{sub 2}O)(µ-dib)]{sub n} (1), [Cd(µ-tdc)(H{sub 2}O)(µ-dib)]{sub n} (2), and ([Cd{sub 2}(µ{sub 3}-tdc){sub 2}(µ-dimb){sub 2}]·(H{sub 2}O)){sub n}(3). These MOFs were characterized by FT-IR spectroscopy, elemental, thermal (TG, DTA, DTG and DSC), and single-crystal X-ray diffraction analyses. Isomorphous complexes 1 and 2 reveal polycatenated 2D+2D→3D framework based on an undulated (4,4)-sql layer. Complex 3 exhibits a new 4-fold interpenetrating 3D framework with the point symbol of 6{sup 6}. Molecular simulations were used to assess the potentials of the complexes for H{sub 2} storage application. Moreover, these coordination polymers exhibit blue fluorescent emission bands in the solid state at room temperature. - Graphical abstract: In this study, hydrothermal reactions of rigid 1,4-bis(imidazol-1-yl)benzene (dib) and 1,4-bis(imidazol-1-yl)-2,5-dimethylbenzene (dimb) with deprotonated thiophene-2,5-dicarboxylic acid (H{sub 2}tdc) in the presence of Zn(II) and Cd(II) salts in H{sub 2}O produced three new metal–organic frameworks. Isomorphous complexes 1 and 2 reveal polycatenated 2D+2D→3D framework based on an undulated (4,4)-sql layer. Complex 3 exhibits a new 4-fold interpenetrating 3D framework with the point symbol of 6{sup 6}. Molecular simulations were used to assess the potentials of the complexes for H{sub 2} storage application. These coordination polymers exhibit blue fluorescent emission bands in the solid state at room temperature. Display Omitted - Highlights: • Complexes 1 and 2 display polycatenated 2D+2D→3D framework. • Complex 3 exhibits a new 4-fold interpenetrating 3D framework. • Complex 1 adsorbs the highest amount of

  17. 3,5-Dibromo-2-[2,5-dibut­oxy-4-(3,5-dibromo­thio­phen-2-yl)phen­yl]thio­phene

    PubMed Central

    Teh, Chin Hoong; Daik, Rusli; Mat Salleh, Muhammad; Mohamed Tahir, Mohamed Ibrahim; Kassim, Mohammad B.

    2011-01-01

    The title mol­ecule, C22H22Br4O2S2, is centrosymmetric with an inversion centre located at the centre of the benzene ring. The 3,5-dibromo­thio­phene groups are twisted relative to the benzene ring, making a dihedral angle of 41.43 (9)°. PMID:22199704

  18. Proton magnetic resonance studies of 2'-,3'-, and 5'-deoxyadenosine conformations in solution.

    PubMed Central

    Westhof, E; Plach, H; Cuno, I; Lüdemann, H D

    1977-01-01

    Proton magnetic resonance studies of 2'-deoxyadenosine (2'-dA), 3'-deoxyadenosine (3'-dA), 5'-deoxyadenosine (5'-dA) and 8-bromo-5'-deoxyadenosine (8-Br-5'-dA) have been carried out in the temperature range between -60 degrees and +40 degrees C for ND3 solutios, +40 degrees and +100 degrees C for D2O solutions, and finally +10 degrees and +60 degrees C for pyridine solutions. The analysis is based on the two-state S in equilibrium N model of the ribose moiety proposed by Altona and Sundaralingam. In all solvents, 2'-dA favours slightly the S state of the ribose and the g+ conformer of the exocyclic CH2OH group. However, 3'-dA prefers strongly the N state of the ribose and the g+ conformation. Both the S and N states of the ribose are equally favoured by 5'-DA and 8-Br-5'-dA. Evidence for the existence of an intramolecular hydrogen bond between 0(5') and N3 in purine (beta)-nucleosides is presented. It is also concluded that cordycepin (3'-dA) exists in solution mainly in the anti conformation of the base relative to the ribose. PMID:301272

  19. Molecular Mechanisms of 2, 3′, 4, 4′, 5-Pentachlorobiphenyl-Induced Thyroid Dysfunction in FRTL-5 Cells

    PubMed Central

    Guo, Hongwei; Li, Wen; Tang, Jinmei; Xu, Bojin; Sun, Minne; Ding, Guoxian; Jiang, Lin; Cui, Dai; Zheng, Xuqin; Duan, Yu

    2015-01-01

    Polychlorinated biphenyls (PCBs) can severely interfere with multiple animals and human systems. To explore the molecular mechanisms underlying 2, 3′, 4, 4′, 5- pentachlorobiphenyl (PCB118)-induced thyroid dysfunction, Fischer rat thyroid cell line-5(FRTL-5) cells were treated with either different concentrations of PCB118 or dimethyl sulfoxide (DMSO). The effects of PCB118 on FRTL-5 cells viability and apoptosis were assessed by using a Cell Counting Kit-8 assay and apoptosis assays, respectively. Quantitative real-time polymerase chain reaction was used to quantify protein kinase B (Akt), Forkhead box protein O3a (FoxO3a), and sodium/iodide symporter (NIS) mRNA expression levels. Western blotting was used to detect Akt, phospho-Akt (p-Akt), FoxO3a, phospho-FoxO3a (p-FoxO3a), and NIS protein levels. Luciferase reporter gene technology was used to detect the transcriptional activities of FoxO3a and NIS promoters. The effects of the constitutively active Akt (CA-Akt) and dominant-negative Akt (DN-Akt) plasmids on p-Akt, p-FoxO3a, and NIS levels were examined in PCB118-treated FRTL-5 cells. The effects of FoxO3a siRNA on FoxO3a, p-FoxO3a, and NIS protein levels were examined in the PCB118-treated FRTL-5 cells. The effects of pcDNA3 (plsmid vectors designed for high-level stable and transient expression in mammalian host)-FoxO3a on NIS promoter activity were examined in the PCB118-treated FRTL-5 cells. Our results indicated that relatively higher PCB118 concentrations can inhibit cell viability in a concentration- and time-dependent manner. Akt, p-Akt, and p-FoxO3a protein or mRNA levels increased significantly in PCB118-treated groups and NIS protein and mRNA levels decreased considerably compared with the control groups. FoxO3a promoter activity increased significantly, whereas NIS promoter activity decreased. These effects on p-FoxO3a and NIS could be decreased by the DN-Akt plasmid, enhanced by the CA-Akt plasmid, and blocked by FoxO3a siRNA. The overexpressed

  20. Li0.5Al0.5Mg2(MoO4)3

    PubMed Central

    Ennajeh, Ines; Zid, Mohamed Faouzi; Driss, Ahmed

    2013-01-01

    The title compound, lithium/aluminium dimagnesium tetra­kis­[orthomolybdate(VI)], was prepared by a solid-state reaction route. The crystal structure is built up from MgO6 octa­hedra and MoO4 tetra­hedra sharing corners and edges, forming two types of chains running along [100]. These chains are linked into layers parallel to (010) and finally linked by MoO4 tetra­hedra into a three-dimensional framework structure with channels parallel to [001] in which lithium and aluminium cations equally occupy the same position within a distorted trigonal–bipyramidal coordination environment. The title structure is isotypic with LiMgIn(MoO4)3, with the In site becoming an Mg site and the fully occupied Li site a statistically occupied Li/Al site in the title structure. PMID:24426975

  1. Modulation of dopamine transmission by 5HT2C and 5HT3 receptors: a role in the antidepressant response.

    PubMed

    Dremencov, Eliyahu; Weizmann, Yifat; Kinor, Noa; Gispan-Herman, Iris; Yadid, Gal

    2006-02-01

    Dopaminergic mesolimbic and mesocortical systems are fundamental in hedonia and motivation. Therefore their regulation should be central in understanding depression treatment. This review highlights the dopaminergic activity in relation to depressive behavior and suggests two putative receptors as potential targets for research and development of future antidepressants. In this article we review data that describe the role of serotonin in regulating dopamine release, via 5HT2C and 5HT3 receptors. This action of serotonin appears to be linked to depressive-like behavior and to onset of behavioral effects of antidepressants in an animal model of depression. We suggest that drugs or strategies that decrease 5HT2C and increase 5HT3 receptor-mediated dopamine release in the limbic areas of the brain may provide a fast onset of therapeutic effect. Clinical and basic research data supporting this hypothesis are discussed. PMID:16475958

  2. Downwind O3 and PM2.5 speciation during the wildfires in 2002 and 2010

    NASA Astrophysics Data System (ADS)

    Kang, Choong-Min; Gold, Diane; Koutrakis, Petros

    2014-10-01

    A series of wildfires in northern Quebec, early July 2002, and in southern Quebec, late May 2010, resulted in severe air pollution downwind. Downwind exposures were investigated to estimate the impact on outdoor and indoor environments. The plumes derived from the wildfires resulted in an increase of over 10 ppbv ozone (O3) concentrations in both major cities and rural areas, while O3 enhancement was not observed at locations adjacent to wildfire burning areas. Temporal trend in PM2.5 concentration showed a peak of 105.5 μg/m3 on July 7, 2002, while on May 31, 2010 the peak was 151.1 μg/m3 in Boston downwind. PM2.5 speciation showed similar trends between the episodes, along with spikes in the PM2.5/PM10 ratio, and in the concentrations of Black Carbon, ΔC (i.e., UV absorbing compounds minus Black Carbon), Organic Carbon (OC), potassium, and chlorine. OC was the most dominant constituent of the PM2.5 mass in the wildfires. The dominant specific carbon fractions include OC fraction 3, pyrolysis carbon, and EC fraction 1, likely due to pyrolysis of structural components of wood. Indoor PM2.5 peaks at two houses corresponded well with the ambient PM2.5 peak, along with the elemental composition, which could indicate an impact of wildfires on indoor air pollution exposure.

  3. Gamma-ray irradiation induced bulk photochromism in WO3-P2O5 glass

    NASA Astrophysics Data System (ADS)

    Shen, Wei; Baccaro, Stefania; Cemmi, Alessia; Xu, Xiaoqing; Chen, Guorong

    2015-11-01

    In the present work, photochromism of WO3-P2O5 glass under gamma-ray irradiation was reported. As-prepared glass samples with different WO3 content are all optically transparent in the visible wavelength range thanks to the addition of a small amount of oxidizing couple Sb2O3-NaNO3. The photochromic properties are identified by transmission spectra of the glasses before and after irradiation. The results show that the irradiation induced darkening results from the reduction of W6+ to W5+ or W4+. The existence of WO6 clusters in glasses of high WO3 content is proved by XPS, which is the main reason for the obvious photochromic effects. The WO3-P2O5 glass is a promising candidate in gamma-ray sensitive detector.

  4. Polarization degrees of 3p 2P3/2-3s 2S1/2 transition in O5+(1s 23p) produced in collisions of O6+ with He and H2

    NASA Astrophysics Data System (ADS)

    Zhao, Y. Q.; Liu, L.; Xue, P.; Wang, J. G.; Janev, R. K.

    2010-09-01

    Electron capture processes in collisions of O6+ with ground state He and H2 are investigated using the two-centre atomic orbital close-coupling method. Total and state-selective one-electron capture cross sections are obtained for collision energies between 0.5 and 300 keV/u. The comparison with the available experimental state-selective capture data in the overlapping energy range (0.5-100 keV/u for O6++He and 0.5-8 keV/u for O6++H2) shows a good overall agreement. The polarization degrees of 3p 2P3/2-3s 2S1/2 radiation from O5+(3p 2P3/2) produced in O6++He and O6++H2 collisions are calculated from the magnetic substate-selective cross sections with inclusion of cascade contributions from higher n = 4 and n = 5 states. Good agreement is obtained with the experimental data available in the energy range 3-8 keV/u. Below ~10 keV/u, the polarization degrees of O5+(3p 2P3/2) in both collision systems exhibit an oscillatory structure and above this energy they steadily increase with the increase of collision energy, reaching the values of about 0.37 at 300 keV/u. The energy behaviour of the polarization degree of O5+(3p 2P3/2) in the O6++He collision system is determined almost exclusively by the direct electron capture to 3p0 and 3p1 states of O5+, while in the case of the O6++H2 collision system in the energy region below ~40 keV/u it is strongly affected by the cascade contributions from the 4l states, which are the dominant capture states in this system.

  5. Cycloadditions of 1,2,3-Triazines Bearing C5-Electron Donating Substituents: Robust Pyrimidine Synthesis.

    PubMed

    Glinkerman, Christopher M; Boger, Dale L

    2015-08-21

    The examination of the cycloaddition reactions of 1,2,3-triazines 17-19, bearing electron-donating substituents at C5, are described. Despite the noncomplementary 1,2,3-triazine C5 substituents, amidines were found to undergo a powerful cycloaddition to provide 2,5-disubstituted pyrimidines in excellent yields (42-99%; EDG = SMe > OMe > NHAc). Even select ynamines and enamines were capable of cycloadditions with 17, but not 18 or 19, to provide trisubstituted pyridines in modest yields (37-40% and 33% respectively). PMID:26172042

  6. Empirical model studies on relaxor behaviour in Bi2.5La1.5Ti3O12 ceramic

    NASA Astrophysics Data System (ADS)

    Selvamani, Rachna; Pandey, Adityanarayan; Gupta, S. M.

    2016-05-01

    Relaxor like dielectric characteristics have been observed for high La-concentration substituted bismuth titanate Bi2.5La1.5Ti3O12 ceramic. Frequency dependent temperature of dielectric maxima has been fitted with models of non-interacting and interacting polar region. This study clearly reveals slowing down of nano-polar dynamics into cluster like glass as proposed by cluster glass model. La-substitution at Bi-site of Bi2O2 layer is responsible for the random field generation.

  7. Preparations, structures and properties of heterobimetallic complexes based on tetrahydrofuran-2,3,4,5-tetracarboxylate

    NASA Astrophysics Data System (ADS)

    Jia, Tian-Jing; Li, Shu-Mu; Cao, Wei; Li, Li-Cun; Zheng, Xiang-Jun; Yuan, Da-Qiang

    2013-05-01

    Transition heterobimetallic metal-organic frameworks based on tetrahydrofuran-2,3,4,5-tetracarboxylicate (FTA), namely [M(H2O)6][Cu2M(FTA)2(H2O)2]·4H2O [M=Mn (1), Co (2)], and [CuZn(FTA)(H2O)5]·H2O (3) have been synthesized and characterized. Single-crystal X-ray diffraction indicates that complexes 1 and 2 are isomorphic. In 1 and 2, FTA ligand links the metal ions to a 2-D wave-like negative-charged layer with a topology of {4;62}2{4;63;82}2{6}. They possess 1-D channels with [M(H2O)6]2+ and lattice water molecules enclathrated. While in the complex 3, Cu2+ and Zn2+ ions are bridged by FTA to a 2-D neutral layer structure with a {8}2{84;122} topology. Magnetic properties of 1-3 were analyzed in connection with their structures, which show that there exist weak antiferromagnetic interactions between metal ions.

  8. Synthesis and luminescent properties of Sr3Al2O5Cl2: Eu2+, Dy3+ rod-like nanocrystals

    NASA Astrophysics Data System (ADS)

    Wang, Zhengliang; Zhang, Qiuhan; Rong, Meizhu; Tan, Huiying; Wang, Qin; Zhou, Qiang; Chen, Guo

    2016-08-01

    White long afterglow phosphor with nano-rods, Sr3Al2O5Cl2: Eu2+, Dy3+, has been successfully synthesized by the solid state reaction. Their structure, morphology, scanning electron microscopy, luminescent properties and long afterglow properties were investigated by X-ray diffraction, transmission electron microscopy luminescence spectra and the luminescence decay curve. The obtained phosphor Sr3Al2O5Cl2: Eu2+, Dy3+ exhibits two broad emission bands, which are located at ∼445 nm and ∼590 nm, respectively. White light can be observed from this phosphor with appropriate CIE values (x = 0.357, y = 0.332). The white afterglow duration of this phosphor is about 0.5 h (>0.35 mcd/m2).

  9. Ln3I5(S2N2)(S2)(THF)10 - a new type of molecular compounds.

    PubMed

    Fagin, A A; Fukin, G K; Cherkasov, A V; Shestakov, A F; Pushkarev, A P; Balashova, T V; Maleev, A A; Bochkarev, M N

    2016-03-21

    Unprecedented complexes of the composition Ln3I5(S2N2)(S2)(THF)10 were obtained in the reactions of neodymium and dysprosium iodide-nitrides with sulfur. The inorganic core of the molecules contains the cyclic fragments Ln(μ-S2)Ln, LnSNSN and LnSN. Ten of the fourteen atoms of the core are coplanar, the remaining four S2 and I2 atoms lie in the other two orthogonal planes. The dysprosium complex upon excitation with UV light exhibits the metal-centered luminescence characteristic of the Dy(3+) ion. Geometric parameters of the molecules, computational data, electron spectroscopy and fluorescence suggest the existence of some conjugation in the mentioned heterocycles. PMID:26842841

  10. Polarization degree differences for the 3p2P3/2-3s2S1/2 transition of N4+(3p2P3/2) produced in N5+-He and N5+-H2 collisions

    NASA Astrophysics Data System (ADS)

    Liu, L.; Zhao, Y. Q.; Wang, J. G.; Janev, R. K.; Tanuma, H.

    2010-01-01

    The magnetic substate-selective single-electron-capture cross sections in collisions of N5+ with He and H2 are calculated using the two-center atomic orbital close-coupling method, and the polarization of emitted radiation from the excited state of N4+ is investigated for projectile energies between 1.2 and 7 keV/u. The polarization degrees for the 3p2P3/2-3s2S1/2 transition of N4+(3p2P3/2) produced in N5++He and N5++H2 electron-capture collisions are in general agreement with the experimental measurements. It is found both experimentally and theoretically that there exists a large difference between the polarization degrees of this radiation resulting from the N5++He and N5++H2 electron-capture collisions, namely, ~0.25 and ~0, respectively. By studying the time evolution of electron-capture dynamics in the two systems we have found that this difference is caused mainly by the difference in the interactions in the two systems at relatively small internuclear distances, consistent with the molecular picture of the collision dynamics.

  11. (2E)-1-(2,5-Dimethyl-3-thien­yl)-3-(2-meth­oxy­phen­yl)prop-2-en-1-one

    PubMed Central

    Asiri, Abdullah M.; Khan, Salman A.; Tahir, M. Nawaz

    2010-01-01

    In the title compound, C16H16O2S, the central propenone group is almost planar (r.m.s. deviation = 0.009 Å) and subtends dihedral angles of 8.55 (8) and 16.22 (8)° to the 2-meth­oxy­phenyl and 2,5-dimethyl­thio­phene residues, respectively. The dihedral angle between the ring systems is 23.47 (5)°. In the crystal, mol­ecules are linked by weak C—H⋯π inter­actions and aromatic π–π stacking [phenyl ring centroid–centroid separation = 3.6418 (11) Å; thio­phene–thio­phene ring separation = 3.8727 (9) Å]. PMID:21588700

  12. Prenatal detection of 5q14.3 duplication including MEF2C and brain phenotype.

    PubMed

    Cesaretti, Claudia; Spaccini, Luigina; Righini, Andrea; Parazzini, Cecilia; Conte, Giorgio; Crosti, Francesca; Redaelli, Serena; Bulfamante, Gaetano; Avagliano, Laura; Rustico, Mariangela

    2016-05-01

    The 5q14.3 duplication is a rare condition comprising speech and developmental delay, microcephaly, and mild ventriculomegaly. The region 5q14.3 contains several genes but the predominant role for the onset of the neurodevelopmental phenotype has been attributed to MEF2C. We describe the prenatal identification of 5q14.3 duplication, including MEF2C, in a monochorionic twin pregnancy with corpus callosum anomalies, confirmed by autopsy. To the best of our knowledge, this cerebral finding has been observed for the first time in 5q14.3 duplication patients, possibly widening the neurological picture of this scarcely known syndrome. A pathogenetic role of MEF2C overexpression in brain development may be assumed, but further studies are needed. © 2016 Wiley Periodicals, Inc. PMID:26864752

  13. Temperature dependent absorption cross-sections of HNO3 and N2O5

    NASA Technical Reports Server (NTRS)

    Rattigan, Oliver V.; Harwood, Matthew H.; Jones, Rod L.; Cox, Richard A.

    1994-01-01

    Absorption cross-sections for HNO3 and N2O5 have been measured in the wavelength region 220-450 nm, using a dual beam diode array spectrometer with a spectral resolution of 0.3 nm. The results for both compounds are in good agreement with recommended values at room temperature. However, the cross-sections of both HNO3 and N2O5 show a marked reduction with decreasing temperature in the range 295-233 K. The calculated photolysis rate of HNO3 at the low temperatures and high solar zenith angles characteristic of the polar winter and spring is significantly lower than previously estimated.

  14. 3-[(N-Methyl­anilino)meth­yl]-5-(thio­phen-2-yl)-1,3,4-oxadiazole-2(3H)-thione

    PubMed Central

    El-Emam, Ali A.; Al-Omar, Mohamed A.; Ghabbour, Hazem A.; Fun, Hoong-Kun; Chia, Tze Shyang

    2012-01-01

    In the title compound, C14H13N3OS2, the thio­phene ring is disordered over two orientations by ca 180° about the C—C bond axis linking the ring to the rest of the mol­ecule, with a site-occupancy ratio of 0.651 (5):0.349 (5). The central 1,3,4-oxadiazole-2(3H)-thione ring forms dihedral angles of 9.2 (5), 4.6 (11) and 47.70 (7)° with the major and minor parts of the disordered thio­phene ring and the terminal phenyl ring, respectively. In the crystal, no significant inter­molecular hydrogen bonds are observed. The crystal packing is stabilized by π–π inter­actions [centroid–centroid distance = 3.589 (2) Å]. PMID:22590242

  15. PI(3,5)P2 biosynthesis regulates oligodendrocyte differentiation by intrinsic and extrinsic mechanisms

    PubMed Central

    Mironova, Yevgeniya A; Lenk, Guy M; Lin, Jing-Ping; Lee, Seung Joon; Twiss, Jeffery L; Vaccari, Ilaria; Bolino, Alessandra; Havton, Leif A; Min, Sang H; Abrams, Charles S; Shrager, Peter; Meisler, Miriam H; Giger, Roman J

    2016-01-01

    Proper development of the CNS axon-glia unit requires bi-directional communication between axons and oligodendrocytes (OLs). We show that the signaling lipid phosphatidylinositol-3,5-bisphosphate [PI(3,5)P2] is required in neurons and in OLs for normal CNS myelination. In mice, mutations of Fig4, Pikfyve or Vac14, encoding key components of the PI(3,5)P2 biosynthetic complex, each lead to impaired OL maturation, severe CNS hypomyelination and delayed propagation of compound action potentials. Primary OLs deficient in Fig4 accumulate large LAMP1+ and Rab7+ vesicular structures and exhibit reduced membrane sheet expansion. PI(3,5)P2 deficiency leads to accumulation of myelin-associated glycoprotein (MAG) in LAMP1+perinuclear vesicles that fail to migrate to the nascent myelin sheet. Live-cell imaging of OLs after genetic or pharmacological inhibition of PI(3,5)P2 synthesis revealed impaired trafficking of plasma membrane-derived MAG through the endolysosomal system in primary cells and brain tissue. Collectively, our studies identify PI(3,5)P2 as a key regulator of myelin membrane trafficking and myelinogenesis. DOI: http://dx.doi.org/10.7554/eLife.13023.001 PMID:27008179

  16. PI(3,5)P2 biosynthesis regulates oligodendrocyte differentiation by intrinsic and extrinsic mechanisms.

    PubMed

    Mironova, Yevgeniya A; Lenk, Guy M; Lin, Jing-Ping; Lee, Seung Joon; Twiss, Jeffery L; Vaccari, Ilaria; Bolino, Alessandra; Havton, Leif A; Min, Sang H; Abrams, Charles S; Shrager, Peter; Meisler, Miriam H; Giger, Roman J

    2016-01-01

    Proper development of the CNS axon-glia unit requires bi-directional communication between axons and oligodendrocytes (OLs). We show that the signaling lipid phosphatidylinositol-3,5-bisphosphate [PI(3,5)P2] is required in neurons and in OLs for normal CNS myelination. In mice, mutations of Fig4, Pikfyve or Vac14, encoding key components of the PI(3,5)P2 biosynthetic complex, each lead to impaired OL maturation, severe CNS hypomyelination and delayed propagation of compound action potentials. Primary OLs deficient in Fig4 accumulate large LAMP1(+) and Rab7(+) vesicular structures and exhibit reduced membrane sheet expansion. PI(3,5)P2 deficiency leads to accumulation of myelin-associated glycoprotein (MAG) in LAMP1(+)perinuclear vesicles that fail to migrate to the nascent myelin sheet. Live-cell imaging of OLs after genetic or pharmacological inhibition of PI(3,5)P2 synthesis revealed impaired trafficking of plasma membrane-derived MAG through the endolysosomal system in primary cells and brain tissue. Collectively, our studies identify PI(3,5)P2 as a key regulator of myelin membrane trafficking and myelinogenesis. PMID:27008179

  17. Process for manufacturing bis(2-methoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracene

    SciTech Connect

    Rasmussen, Paul George; Lawton, Richard Graham

    2014-06-03

    A process to manufacture substituted tetracyano-hexaazatricyclics with the substitutions occurring at the 9 and 10 hydrogens. The process begins with 2,3-dichloro-5,6-dicyanopyrazine, which is reacted to form the desired tetracyano-hexaazatricyclic. Different process embodiments enable different reaction paths to the desired tetracyano-hexaazatricyclic. Different tetracyano-hexaazatricyclic embodiments include bis(2-methoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracene and bis(2-methoxyethoxyethyl)-2,3,6,7-tetracyano-1,4,5,8,9,10-hexazaanthracen- e.

  18. Is NO3/N2O5 chemistry a source of aerosol HNO3 in the San Joaquin Valley?

    NASA Astrophysics Data System (ADS)

    Minejima, C.; Wooldridge, P. J.; Cohen, R. C.

    2009-12-01

    Sensitive and continuous measurements of NO3 + N2O5 concentrations were made at Arvin from March 1 to March 30, 2007 using Thermal Dissociation-Laser Induced Fluorescence (TD-LIF) to investigate the role of NO3 and N2O5 as a cause of high ammonium nitrate (NH4NO3) aerosol concentrations in California’s San Joaquin Valley (SJV). NH4NO3 is produced via a reaction of HNO3 and NH3. And HNO3 is the limiting reagent for NH3 is emitted in large amount from agricultural sources and motor vehicles in the SJV. NO3 and N2O5 play an important part in producing HNO3. Nighttime production of HNO3 through a heterogeneous N2O5 reaction with H2O on aerosol surfaces was investigated by measuring the NO3 + N2O5 concentrations. Peak values of N2O5 mixing ratio often exceeded 100 pptv and ranged between 25-320 pptv. Size resolved particle number was measured to estimate aerosol surface load and it was found that heterogeneous N2O5 reaction with the estimated surface load could explain only up to a few % of HNO3 production. Here the necessary HNO3 production is calculated by assuming the aerosol lifetime with respect to deposition and/or transport out of PBL is 1 day. Other possible passes to produce HNO3 are the day time NO2 + OH reaction, nighttime NO3 + anthropogenic HC reactions, and NO3 + biogenic HC reactions. Contribution of each pass was estimated by auxiliary measurements and knowledge from literature. Daytime HNO3 production was calculated from the measured NO2 concentration at the nearest CARB site and OH concentration from literature to show that it may account for ~25 % of HNO3 required. Total non methane hydrocarbons (NMHCs), which is mostly anthropogenic, is measured at the CARB site. Assuming the similar compositions of NMHCs in Sacramento, NO3 + anthropogenic HCs are calculated to be as fast to explain 40 - 70 % of NO3 + N2O5 loss. HNO3 yield from these reactions are not well known. The upper limit of HNO3 production, however, can be estimated by assuming unity yield

  19. Highly functionalized alkenes produced from base-free organocatalytic Wittig reactions: (E)-3-benzylidenepyrrolidine-2,5-dione, (E)-3-benzylidene-1-methylpyrrolidine-2,5-dione and (E)-3-benzylidene-1-tert-butylpyrrolidine-2,5-dione.

    PubMed

    Schirmer, Marie Luis; Spannenberg, Anke; Werner, Thomas

    2016-06-01

    The Wittig reaction is a fundamental transformation for the preparation of alkenes from carbonyl compounds and phosphonium ylides. The ylides are prepared prior to the olefination step from the respective phosphonium salts by deprotonation utilizing strong bases. A first free-base catalytic Wittig reaction for the preparation of highly functionalized alkenes was based on tributylphosphane as the catalyst. Subsequently we developed a system employing a phospholene oxide as a pre-catalyst and trimethoxysilane as reducing agent which operates under milder conditions. The title compounds, (E)-3-benzylidenepyrrolidine-2,5-dione, C11H9NO2, (I), the methylpyrrolidine derivative, C12H11NO2, (II), and the tert-butylpyrrolidine derivative, C15H17NO2, (III), have been synthesized by base-free catalytic Wittig reactions. In the crystal of (I), molecules are linked into centrosymmetric dimers via pairs of N-H...O hydrogen bonds. Furthermore, in the crystal structure of (III), there are two molecules in the asymmetric unit, whereas in (I) and (II), only one molecule is present. PMID:27256699

  20. Highly pathogenic avian influenza viruses H5N2, H5N3, and H5N8 in Taiwan in 2015.

    PubMed

    Lee, Ming-Shiuh; Chen, Li-Hsuan; Chen, Yen-Ping; Liu, Yu-Pin; Li, Wan-Chen; Lin, Yeou-Liang; Lee, Fan

    2016-05-01

    A severe epidemic, affecting mainly goose populations, broke out in early January 2015. The causative agents were identified as novel H5 avian influenza viruses carrying N2, N3, and N8 subtypes of the neuraminidase gene. From January 8 to February 11, 766 waterfowl and poultry farms were invaded by the H5 viruses, and more than 2.2 million geese died or were culled. Phylogenetic analysis suggested that these avian influenza viruses derived from the H5 viruses of clade 2.3.4.4 which were emerging in 2014 in East Asia, West Europe, and North America. PMID:27066708

  1. 21 CFR 73.3122 - 4-[(2,4-dimethylphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false 4- -2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one. 73.3122 Section 73.3122 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3122 4-...

  2. 21 CFR 73.3122 - 4-[(2,4-dimethylphenyl)azo]-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false 4- -2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-one. 73.3122 Section 73.3122 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3122 4-...

  3. Accelerators (3/5)

    ScienceCinema

    None

    2011-10-06

    1a) Introduction and motivation 1b) History and accelerator types 2) Transverse beam dynamics 3a) Longitudinal beam dynamics 3b) Figure of merit of a synchrotron/collider 3c) Beam control 4) Main limiting factors 5) Technical challenges Prerequisite knowledge: Previous knowledge of accelerators is not required.

  4. Structural incorporation of As5+ into rhomboclase ((H5O2)Fe3+(SO4)2 · 2H2O) and (H3O)Fe(SO4)2.

    PubMed

    Bolanz, Ralph M; Göttlicher, Jörg; Steininger, Ralph; Wieczorek, Arkadiusz

    2016-03-01

    Iron sulfates represent an essential sink for the toxic element arsenic in arid and semi-arid mining areas with high evaporation rates. Information about the structural incorporation of As(5+) in iron sulfates, however, remains scarce. Here we present evidence for the heterogeneous substitution of S(6+) by As(5+) in the crystal structure of rhomboclase ((H5O2)Fe(3+)(SO4)2 · 2H2O) and its dehydration product (H3O)Fe(SO4)2. Rhomboclase (Rhc) was synthesized in the presence of As(5+) with molar As/Fe ratios of 0, 0.25, 0.5, 0.75 and 1.0, resulting in As loads of 0.0, 0.93, 1.44, 1.69 and 1.87 wt.%, respectively. The unit cell parameters of Rhc increase from 9.729(6), 18.303(2), and 5.432(1) Å for a, b, and c, to 9.745(9), 18.332(5), and 5.436(8) Å when Rhc is crystallized at a molar As/Fe ratio of 1. Simultaneously, the crystallite size decreased from 304 to 176 nm. In situ dehydration of Rhc to (H3O)Fe(SO4)2, investigated by powder X-ray diffraction, shows that Rhc starts to dehydrate at 76 °C, which is completed at 86 °C. The presence of As(5+) does not impact the start or end temperatures of Rhc dehydration but does accelerate the dehydration. X-ray absorption fine structure spectroscopy (EXAFS) reveals that S(6+), in the Rhc and (H3O)Fe(SO4)2 structure, is replaced by As(5+), while the polymerization of AsO4-tetrahedra and FeO6-octahedra during the formation of (H3O)Fe(SO4)2 results in a strong distortion of the AsO4-tetrahedron. PMID:26735735

  5. Photoelectrochemical properties of Fe2O3-Nb2O5 films prepared by sol-gel method.

    PubMed

    Miyake, Hidekazu; Kozuka, Hiromitsu

    2005-09-29

    Fe2O3-Nb2O5 coating films of various Nb/(Fe + Nb) mole ratios were prepared on nesa silica glass substrates from Fe(NO3)3.9H2O - NbCl5 - CH3(CH2)2CH2OH - CH3COOH solutions by the sol-gel method. The photoanodic properties were studied in a three-electrode cell with an aqueous buffer solution of pH = 7 as the supporting electrolyte. The crystalline phases identified were alpha-Fe2O3 (Nb/(Fe + Nb) = 0), alpha-Fe2O3 + FeNbO4 (Nb/(Fe + Nb) = 0.25), FeNbO4 (Nb/(Fe + Nb) = 0.5), FeNbO4 + Nb2O5 (Nb/(Fe + Nb) = 0.75), and Nb2O5 (Nb/(Fe + Nb) = 1). When the Nb/(Fe + Nb) mole ratio increased from 0 to 0.25, the crystalline phases changed from alpha-Fe2O3 to alpha-Fe2O3 + FeNbO4, the photoanodic current under white light illumination increased, and the photoanodic current under monochromatized light illumination increased in both visible and ultraviolet regions. When the Nb/(Fe + Nb) ratio increased over 0.25, the crystalline phases changed to FeNbO4, FeNbO4 + Nb2O5, or Nb2O5, and the photoanodic current decreased. The sample consisting of alpha-Fe2O3 and FeNbO4 (Nb/(Fe + Nb) = 0.25) exhibited photoresponse extending to 600 nm and an IPCE of 18% at a wavelength of 325 nm. PMID:16853304

  6. Group theoretical analysis of the H3+ +H2 ↔ H5+ reaction

    NASA Astrophysics Data System (ADS)

    Lin, Zhou

    2016-06-01

    The H3+ +H2 →H2 + H3+ proton transfer reaction is complicated due to the proton scrambling from the large amplitude motions in the H5+ intermediate. In order to understand this reaction, high-resolution spectroscopic studies are necessary for the reactants/products and the intermediate, and the group theoretical analysis is an essential aspect in the prediction and interpretation of these spectra. With five indistinguishable protons, H5+ is characterized using the G240 complete nuclear permutation-inversion (CNPI) group. For most of the configurations sampled by the reaction path, the feasible permutations depend on the distance between the H3+ and H2 fragments. Subgroups of G240 can be used to describe these feasible permutations. Specifically, we consider two limits of the molecular configurations. The equilibrium structure of H5+ , i.e., [H2 -H -H2 ]+, can be described using the G16 molecular symmetry group, while the dissociation products, i.e., H3+ ⋯H2 , require the G24 molecular symmetry group. In the present study, a group theoretical analysis is performed for both limits, providing the symmetries for the nuclear spins and rovibrational wave functions. Also, spectroscopic properties for [H2 -H -H2 ]+, particularly rovibrational couplings and electric dipole selection rules, as well as correlations of energy levels between [H2 -H -H2 ]+ and H3+ ⋯H2 , are obtained.

  7. Conversion of Y3(Al,Ga)5O12:Tb3+ to Y2Si2O7:Tb3+ thin film by annealing at higher temperatures

    NASA Astrophysics Data System (ADS)

    Yousif, A.; Swart, H. C.; Ntwaeaborwa, O. M.; Coetsee, E.

    2013-04-01

    Y3(Al,Ga)5O12:Tb thin films were grown on Si(1 0 0) substrates in an Ar working atmosphere by using the pulsed laser deposition (PLD) technique. The Y3(Al,Ga)5O12:Tb target was ablation deposited onto a Si(1 0 0) substrate using a 266 nm Nd:YAG laser. The influence of post deposition annealing temperature (1073 K to 1473 K) on the excitation and the emission bands, and the crystal structure of the thin film were monitored. X-ray diffraction (XRD) and photoelectron spectroscopy (XPS) depth profiles of the thin films indicate that there were annealing induced changes in the crystal structure and chemical composition causing changes in the excitation bands. These changes (structure and composition) are attributed to interdiffusion of atomic species between the substrate and the Y3(Al,Ga)5O12:Tb3+ thin film. The XRD and XPS data confirm that after annealing, Y3(Al,Ga)5O12:Tb3+ was converted to Y2Si2O7:Tb3+. A change in the relative ratios of the excitation band intensities was measured. Atomic force microscopy (AFM) showed that topographical changes also occurred during the annealing process. Thermoluminescence (TL) glow curves of the Y3(Al,Ga)5O12:Tb3+ thin films before and after annealing, indicated the presence of different types of traps resulting from the change on the structure of the thin films.

  8. The spatial variability of PM_{2.5} over Europe using satellite POLDER-3/PARASOL data

    NASA Astrophysics Data System (ADS)

    Bovchaliuk, A.

    2013-12-01

    The paper presents the results of the monthly mean PM_{2.5} analysis in the period from 2005 to 2013 over the Europe based on the connection between daily fine particle concentrations (PM_{2.5}) by surface in-situ measurements in AIRBASE network and column aerosol optical thickness (AOT) derived from POLDER-3/PARASOL satellite sensor. The regression function between PM_{2.5} and AOT was derived from measurements done over Europe in the period from April to October 2007. Considering 749 match-up data points over 20 fine particle monitoring sites, we found that the POLDER-3/PARASOL derived AOT at 865 nm is correlated with collocated PM_{2.5} measurements with a correlation coefficient 0.62 (RMS=3.26). According to the obtained linear regression {PM}_{2.5}=73.4×{AOT}_{865}+9.6, a significant offset caused an introduction of the threshold of 0.01 in monthly mean AOT for assessment of PM_{2.5} based on satellite data. Therefore, only PM_{2.5} values larger than 10.3 μg/ m^3 can be obtained using this method. According to results the monthly mean PM_{2.5} in the period from 2005 to 2013 over the Europe is usually characterised by values less than 12 μg/m^3 (classified as ``good'' by Air Quality Categories, AQC), but values ranging from 12 to 18 μg/m^3 (classified as ``moderate'') are found in the densely populated and industrial areas, such as the Netherlands, Belgium, the Ruhr and Danube area, Northern Italy, Poland, Romania and Eastern Ukraine. Additionally, the maximum values of PM_{2.5} over Eastern Europe are observed during forest, peat and agricultural wildfires in May 2006 (15-21 μg/m^3), April 2009 (14-18 μg/m^3) and August 2010 (35-55 μg/m^3, classified as ``unhealthy for sensitive groups''). An extended set of aerosol parameters including particle size distribution, complex refractive index, as well as parameters characterising aerosol particle shape and vertical distribution will be analysed in the future work.

  9. CXCR3/CCR5 pathways in metastatic melanoma patients treated with adoptive therapy and interleukin-2

    PubMed Central

    Bedognetti, D; Spivey, T L; Zhao, Y; Uccellini, L; Tomei, S; Dudley, M E; Ascierto, M L; De Giorgi, V; Liu, Q; Delogu, L G; Sommariva, M; Sertoli, M R; Simon, R; Wang, E; Rosenberg, S A; Marincola, F M

    2013-01-01

    Background: Adoptive therapy with tumour-infiltrating lymphocytes (TILs) induces durable complete responses (CR) in ∼20% of patients with metastatic melanoma. The recruitment of T cells through CXCR3/CCR5 chemokine ligands is critical for immune-mediated rejection. We postulated that polymorphisms and/or expression of CXCR3/CCR5 in TILs and the expression of their ligands in tumour influence the migration of TILs to tumours and tumour regression. Methods: Tumour-infiltrating lymphocytes from 142 metastatic melanoma patients enrolled in adoptive therapy trials were genotyped for CXCR3 rs2280964 and CCR5-Δ32 deletion, which encodes a protein not expressed on the cell surface. Expression of CXCR3/CCR5 in TILs and CXCR3/CCR5 and ligand genes in 113 available parental tumours was also assessed. Tumour-infiltrating lymphocyte data were validated by flow cytometry (N=50). Results: The full gene expression/polymorphism model, which includes CXCR3 and CCR5 expression data, CCR5-Δ32 polymorphism data and their interaction, was significantly associated with both CR and overall response (OR; P=0.0009, and P=0.007, respectively). More in detail, the predicted underexpression of both CXCR3 and CCR5 according to gene expression and polymorphism data (protein prediction model, PPM) was associated with response to therapy (odds ratio=6.16 and 2.32, for CR and OR, respectively). Flow cytometric analysis confirmed the PPM. Coordinate upregulation of CXCL9, CXCL10, CXCL11, and CCL5 in pretreatment tumour biopsies was associated with OR. Conclusion: Coordinate overexpression of CXCL9, CXCL10, CXCL11, and CCL5 in pretreatment tumours was associated with responsiveness to treatment. Conversely, CCR5-Δ32 polymorphism and CXCR3/CCR5 underexpression influence downregulation of the corresponding receptors in TILs and were associated with likelihood and degree of response. PMID:24129241

  10. (1R, 3S)-(−)-Trans-PAT: A novel full-efficacy serotonin 5-HT2C receptor agonist with 5-HT2A and 5-HT2B receptor inverse agonist/antagonist activity

    PubMed Central

    Booth, Raymond G.; Fang, Lijuan; Huang, Yingsu; Wilczynski, Andrzej; Sivendran, Sashikala

    2009-01-01

    The serotonin 5-HT2A, 5-HT2B, and 5-HT2C G protein-coupled receptors signal primarily through Gαq to activate phospholipase C (PLC) and formation of inositol phosphates (IP) and diacylglycerol. The human 5-HT2C receptor, expressed exclusively in the central nervous system, is involved in several physiological and psychological processes. Development of 5-HT2C agonists that do not also activate 5-HT2A or 5-HT2B receptors is challenging because transmembrane domain identity is about 75% among 5-HT2 subtypes. This paper reports 5-HT2 receptor affinity and function of (1R,3S)-(−)-trans-1-phenyl-3-dimethylamino-1,2,3,4-tetrahydronaphthalene (PAT), a small molecule that produces anorexia and weight-loss after peripheral administration to mice. (−)-Trans-PAT is a stereoselective full-efficacy agonist at human 5-HT2C receptors, plus, it is a 5-HT2A/5-HT2B inverse agonist and competitive antagonist. The Ki of (−)-trans-PAT at 5-HT2A, 5-HT2B, and 5-HT2C receptors is 410, 1200, and 37 nM, respectively. Functional studies measured activation of PLC/[3H]-IP formation in clonal cells expressing human 5-HT2 receptors. At 5-HT2C receptors, (−)-trans-PAT is an agonist (EC50 = 20 nM) comparable to serotonin in potency and efficacy. At 5-HT2A and 5-HT2B receptors, (−)-trans-PAT is an inverse agonist (IC50 = 490 and 1,000 nM, respectively) and competitive antagonist (KB = 460 and 1400 nM, respectively) of serotonin. Experimental results are interpreted in light of molecular modeling studies indicating the (−)-trans-PAT protonated amine can form an ionic bond with D3.32 of 5-HT2A and 5-HT2C receptors, but, not with 5-HT2B receptors. In addition to probing 5-HT2 receptor structure and function, (−)-trans-PAT is a novel lead regarding 5-HT2C agonist/5-HT2A inverse agonist drug development for obesity and neuropsychiatric disorders. PMID:19397907

  11. Kinetic behavior of WO3-doped Nb2O5 electrochromic thin films

    NASA Astrophysics Data System (ADS)

    Melo, Luciana O.; Dragunski, Douglas C.; Avellaneda, Cesar O.; Pawlicka, Agnieszka

    2003-07-01

    An electrochromic material (EC) reversibly changes its optical characteristics response, coloring and bleaching states when a small voltage or current is passed through it. This phenomenon is used to develop electrochromic devices like smart windows, which control the amount of heat and light entering in a building and optimize energy consumption. The change of the transparency of these devices involves the injection and extraction of small cations and electrons into the EC material and study of the kinetics of ions injection implies on operation understanding of these devices. Pure and doped niobium oxides (Nb2O5) are promising cathodic electrochromic materials and their electrooptical performance depends strongly of its structural morphology. The sol-gel process allows for facile fabrication of large area coatings at a low cost and offers advantages of controlling the composition and microstructure of the films. In order to study the solid sate diffusion of lithium into Nb2O5, Nb2O5:Li+ and Nb2O5:WO3, two electroanalytical techniques have been used i.e. galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS). GITT have been applied in order to obtain the chemical diffusion coefficient of Lix in Nb2O5 doped and undoped films, where the values approaching were of the 2.5x10-11 cm2s-1 at x=0,83, 7.4x10-13 cm2s-1 at x=1.65 and 1.6x10-10 cm2s-1 at x=0.33 for Nb2O5, Nb2O5:Li+ and Nb2O5-WO3 respectively. From these measurements it was also observed that within each film, D increases as x increases.

  12. 3-nitro-1,2,4-triazol-5-one, a less sensitive explosive

    DOEpatents

    Lee, Kien-Yin; Coburn, Michael D.

    1988-01-01

    A less sensitive explosive, 3-nitro-1,2,4-triazol-5-one. The compound 3-nitro-1,2,4-triazol-5-one (NTO) has a crystal density of 1.93 g/cm.sup.3 and calculated detonation velocity and pressure equivalent to those of RDX. It can be prepared in high yield from inexpensive starting materials in a safe synthesis. Results from initial small-scale sensitivity tests indicate that NTO is less sensitive than RDX and HMX in all respects. A 4.13 cm diameter, unconfined plate-dent test at 92% of crystal density gave the detonation pressure predicted for NTO by the BKW calculation.

  13. Stepwise Cluster Assembly Using VO(2)(acac) as a Precursor: cis-[VO(OCH(CH(3))(2))(acac)(2)], [V(2)O(2)(&mgr;-OCH(3))(2)(acac)(2)(OCH(3))(2)], [V(3)O(3){&mgr;,&mgr;-(OCH(2))(3)CCH(3)}(2)(acac)(2)(OC(2)H(5))], and [V(4)O(4)(&mgr;-O)(2)(&mgr;-OCH(3))(2)(&mgr;(3)-OCH(3))(2)(acac)(2)(OCH(3))(2)].2CH(3)CN(1).

    PubMed

    Jiang, Feilong; Anderson, Oren P.; Miller, Susie M.; Chen, John; Mahroof-Tahir, Mohammad; Crans, Debbie C.

    1998-10-19

    The studies of an underexplored synthetic reagent, VO(2)(acac) (Hacac = acetylacetone) and semirational strategies for the formation of a complete series of simple vanadium(V) alkoxide clusters in alcohol-containing solvents. The neutral mono-, di-, tri-, and tetranuclear oxovanadium(V) complexes [V(2)O(2)(&mgr;-OCH(3))(2)(acac)(2)(OCH(3))(2)] (1), [V(4)O(4)(&mgr;-O)(2)(&mgr;-OCH(3))(2)(&mgr;(3)-OCH(3))(2)(acac)(2)(OCH(3))(2)].2CH(3)CN (2), [V(4)O(4)(&mgr;-O)(2)(&mgr;-OCH(3))(2)(&mgr;(3)-OCH(3))(2)(acac)(2)(OCH(3))(2)] (3), [V(3)O(3){&mgr;,&mgr;-(OCH(2))(3)CCH(3)}(2)(acac)(2)(OR)] (R = CH(3) (4), C(2)H(5) (5)), and cis-[VO(OCH(CH(3))(2))(acac)(2)] (6) with alkoxide and acac(-) ligands were obtained by reaction of VO(2)(acac) with a monoalcohol and/or a tridentate alcohol. The structures of complexes 1-3, 5, and 6 were determined by X-ray diffraction methods. Complex 1 crystallized in the monoclinic system, P2(1)/n, with a = 7.8668(5) Å, b = 15.1037(9) Å, c = 8.5879(5) Å, beta = 106.150(1) degrees, V = 980.1(1) Å(3), Z = 2, and R (wR2) = 0.040 (0.121). Complex 2 crystallized in the monoclinic system, P2(1)/n, with a = 8.531(2) Å, b = 14.703(3) Å, c = 12.574(2) Å, beta = 95.95(2) degrees, V = 1568.7(5) Å(3), Z = 2, and R (wR2) = 0.052 (0.127). Complex 3 crystallized in the triclinic system, P&onemacr;, with a = 8.5100(8) Å, b = 8.9714(8) Å, c = 10.3708(10) Å, alpha = 110.761(1) degrees, beta = 103.104(1) degrees, gamma = 100.155(1) degrees, V = 691.85(11) Å(3), Z = 1, and R (wR2) = 0.040 (0.105). Complex 5 crystallized in the monoclinic system, P2(1)/n, with a = 14.019(2) Å, b = 11.171(2) Å, c = 19.447(3) Å, beta = 109.18(1) degrees, V = 2876.5(8) Å(3), Z = 4, and R (wR2) = 0.062 (0.157). Complex 6 crystallized in the monoclinic system, P2(1)/n, with a = 15.0023(8) Å, b = 8.1368(1) Å, c = 26.5598(2) Å, beta = 95.744(1) degrees, V = 3225.89(8) Å(3), Z = 8, and R (wR2) = 0.060 (0.154). Complex 1 is a discrete, centrosymmetric dimer in which two

  14. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene of submicron particle size

    DOEpatents

    Rigdon, Lester P.; Moody, Gordon L.; McGuire, Raymond R.

    2001-01-01

    A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

  15. Preparation of 1,3,5-triamo-2,4,6-trinitrobenzene of submicron particle size

    DOEpatents

    Rigdon, Lester P.; Moody, Gordon L.; McGuire, Raymond R.

    2001-05-01

    A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

  16. 3-(4-Meth-oxy-benzyl-idene)-1,5-dioxa-spiro-[5.5]undecane-2,4-dione.

    PubMed

    Zeng, Wu-Lan; Suo, Jin-Long; Jian, Fang-Fang

    2010-01-01

    In the title mol-ecule, C(17)H(18)O(5), which was prepared by the reaction of (R)-1,5-dioxaspiro-[5.5]undecane-2,4-dione and 4-meth-oxy-benzaldehyde with ethanol, the 1,3-dioxane ring is in a distorted envelope conformation with the spiro C atom forming the flap. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds. PMID:21589023

  17. Unexpected Reactivity of [(η(5) -1,2,4-tBu3 C5 H2 )Ni(η(3) -P3 )] towards Main Group Nucleophiles and by Reduction.

    PubMed

    Mädl, Eric; Balázs, Gábor; Peresypkina, Eugenia V; Scheer, Manfred

    2016-06-27

    The reduction of [Cp'''Ni(η(3) -P3 )] (1; Cp'''=η(5) -1,2,4-tBu3 C5 H2 ) with potassium produces the complex anion [(Cp'''Ni)2 (μ,η(2:2) -P8 )](2-) (2), which contains a realgar-like P8 unit. The anionic triple-decker sandwich complex [(Cp'''Ni)2 (μ,η(3:3) -P3 )](-) (3) with a cyclo-P3 middle deck is obtained when 1 is treated with NaNH2 as a nucleophile. Na[3] can subsequently be oxidized with AgOTf to the neutral triple-decker complex [(Cp'''Ni)2 (μ,η(3:3) -P3 )] (4). In contrast, 1 reacts with LiPPh2 to give the anionic compound [(Cp'''Ni)2 (μ,η(2:2) -P6 PPh2 )](-) (5), a complex containing a bicyclic P7 fragment capped by two Cp'''Ni units. Protonation of Li[5] with HBF4 leads to the neutral complex [(Cp'''Ni)2 (μ,η(2:2) -(HP6 PPh2 )] (6). Adding LiNMe2 to 1 results in [Cp'''Ni(η(2) -P3 NMe2 )](-) (7) becoming accessible, a complex which forms as a result of nucleophilic attack at the cyclo-P3 ring of 1. The complexes K2 [2], Na[3], 4, 6, and Li[7] were fully characterized and their structures determined by single-crystal X-ray diffraction. PMID:27097602

  18. Synthesis of 5-chloroformycin A, 5-chloro-2'-deoxyformycin A and certain related 5,7-disubstituted 3-beta-D-ribofuranosylpyrazolo[4,3-d] pyrimidines from formycin A.

    PubMed Central

    Upadhya, K G; Sanghvi, Y S; Robins, R K; Revankar, G R; Ugarkar, B G

    1986-01-01

    A facile synthesis of 7-amino-5-chloro-3-beta-D-ribofuranosylpyrazolo [4,3-d]pyrimidine (5-chloroformycin A, 6), 7-amino-5-chloro-3-(2-deoxy-beta-D-erythro-pentofuranosyl) pyrazolo [4,3-d]-pyrimidine (5-chloro-2'-deoxyformycin A, 13) and certain related 5,7-disubstituted pyrazolo[4,3-d]pyrimidine ribonucleosides is described starting with formycin A. Thiation of tri-O-acetyloxoformycin B (4b) with phosphorus pentasulfide, followed 3-beta-D-ribofuranosyl-7-thioxopyrazolo[4,3-d] pyrimidin-5(1H,4H,6H)-one (3b) in excellent yield. Chlorination of 4b with either phosphorus oxychloride or phenyl phosphonicdichloride furnished the key intermediate 5,7-dichloro-3-(2,3, 5-tri-O-acetyl-beta-D-ribofuranosyl)pyrazolo[4,3-d]pyrimidine (5a), which on deacetylation afforded 5,7-dichloro-3-beta-D-ribofuranosylpyrazolo [4,3-d]pyrimidine (5b). Ammonolysis of 5a with liquid ammonia gave 6, whereas with MeOH/NH3, a mixture of 6 and 7-methoxy-5-chloro-3-beta-D-ribofuranosylpyrazolo[4,3-d]pyrimidine (7) was obtained. Reaction of 6 with lithium azide and subsequent hydrogenation afforded 5-aminoformycin A (10). Treatment of 5a with thiourea gave 5-chloro-3-(2,3,5-tri-O-acetyl-beta-D-ribofuranosyl) pyrazolo[4,3-d]pyrimidine-7(1H,6H)-thione (8a), which on further reaction with sodium hydrosulfide furnished 3-beta-D-ribofuranosylpyrazolo [4,3-d]pyrimidine-5,7(1H,4H,6H)-dithione (11). The four-step deoxygenation procedure using phenoxythiocarbonylation of the 2'-hydroxy group of the 3', 5'-protected 6 gave 5-chloro-2'-deoxyformycin A (13). PMID:3951995

  19. Characterization of rat brain opioid receptors by (Tyr-3,5-/sup 3/H)1, D-Ala2, Leu5-enkephalin binding

    SciTech Connect

    Benyhe, S.; Toth, G.; Kevei, J.; Szuecs, M.B.; Borsodi, A.; Di Gleria, K.; Szecsi, J.; Sueli-Vargha, H.M.; Medzihradszky, K.

    1985-05-01

    (Tyr-3,5-/sup 3/H)1, D-Ala2, Leu5-enkephalin ((/sup 3/H)DALA) was used for labeling the opioid receptors of rat brain plasma membranes. The labeled ligand was prepared from (Tyr-3,5-diiodo)1, D-Ala2, Leu5-enkephalin by catalytic reductive dehalogenation in the presence of Pd catalyst. The resulting (Tyr-3,5-/sup 3/H)1, D-Ala2, Leu5-enkephalin had a specific activity of 37.3 Ci/mmol. In the binding experiments steady-state level was reached at 24 degrees C within 45 min. The pseudo first order association rate constant was 0.1 min-1. The dissociation of the receptor-ligand complex was biphasic with k-1-s of 0.009 and 0.025 min-1. The existence of two binding sites was proved by equilibrium studies. The high affinity site showed a KD = 0.7 nM and Bmax = 60 fmol/mg protein; the low affinity site had a KD = 5 nM and Bmax = 160 fmol/mg protein. A series of opioid peptides inhibited (/sup 3/H)DALA binding more efficiently than morphine-like drugs suggesting that labeled ligand binds preferentially to the delta subtype of opioid receptors. Modification of the original peptides either at the C or N terminal ends of the molecules resulted in a decrease in their affinity.

  20. 2,8,9-Tris(2-methyl-prop-yl)-2,5,8,9-tetra-aza-1λ(5)-phosphatricyclo-[3.3.3.0(1,5)]undecan-5-ium chloride dihydrate.

    PubMed

    Lee, Junseong; Kim, Youngjo

    2012-12-01

    The asymmetric unit of the title hydrated salt, C18H40N4P(+)·Cl(-)·2H2O, consists of two ionic mol-ecules and four water mol-ecules. The mol-ecular geometry around the penta-coordinate P atom is trigonal-bipyramidal, with a H atom and an apical N atom in axial positions and three N atoms with isobutyl substituents in equatorial positions. The Cl(-) ions and water mol-ecules are connected via O-H⋯Cl hydrogen bonds, forming chains along [100]. The ethyl-ene bridging groups are disordered with refined site-occupancy ratios of 0.578 (9):0.422 (9). PMID:23476161

  1. Benchmark of Atucha-2 PHWR RELAP5-3D control rod model by Monte Carlo MCNP5 core calculation

    SciTech Connect

    Pecchia, M.; D'Auria, F.; Mazzantini, O.

    2012-07-01

    Atucha-2 is a Siemens-designed PHWR reactor under construction in the Republic of Argentina. Its geometrical complexity and peculiarities require the adoption of advanced Monte Carlo codes for performing realistic neutronic simulations. Therefore core models of Atucha-2 PHWR were developed using MCNP5. In this work a methodology was set up to collect the flux in the hexagonal mesh by which the Atucha-2 core is represented. The scope of this activity is to evaluate the effect of obliquely inserted control rod on neutron flux in order to validate the RELAP5-3D{sup C}/NESTLE three dimensional neutron kinetic coupled thermal-hydraulic model, applied by GRNSPG/UNIPI for performing selected transients of Chapter 15 FSAR of Atucha-2. (authors)

  2. Surface characterization studies on the interaction of V2O5-WO3/TiO2 catalyst for low temperature SCR of NO with NH3

    NASA Astrophysics Data System (ADS)

    Zhang, Shule; Zhong, Qin

    2015-01-01

    This study aimed at elucidating the surface characterization of V2O5-WO3/TiO2 catalyst to investigate the interaction of V, W and Ti species for the improvement of the catalytic activity in the SCR reaction at low-temperature. Analysis by XRD, UV-vis, PL spectra and DFT theoretical calculations, XPS, EPR and in situ DRIFT showed that WO3 could interact with TiO2 to improve the electrons transfer, and the WO3 hybridization with V2O5 could also improve the reducibility and formation of reduced V2O5 species for the V2O5-WO3/TiO2 catalyst. These aspects resulted in the NO oxidation and NO3 - decomposition that were responsible for the high catalytic activity of V2O5-WO3/TiO2 catalyst.

  3. 5-(3,4-Dimethyl-benzyl-idene)-2,2-dimethyl-1,3-dioxane-4,6-dione.

    PubMed

    Zeng, Wu-Lan

    2011-06-01

    The title compound, C(15)H(16)O(4), was prepared by the reaction of 2,2-dimethyl-1,3-dioxane-4,6-dione and 3,4-dimethyl-benzaldehyde in ethanol. The 1,3-dioxane ring exhibits an envelope conformation. In the crystal, mol-ecules are linked by weak inter-molecular C-H⋯O hydrogen bonds, forming chains parallel to the b axis. PMID:21754745

  4. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  5. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  6. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  7. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl...-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl-4..., reaction products with N-butyl-2,2,6,6-tetramethyl-4-piperidinamine (PMN P-89-632) is subject to...

  8. A New Oxyborate in the Ternary Phase Diagrams Li 2O- Ln2O 3-B 2O 3: Li 2Ln5O 4(BO 3) 3 ( Ln=Yb, Lu): Crystal Structure of the Ytterbium Phase

    NASA Astrophysics Data System (ADS)

    Jubera, Veronique; Gravereau, Pierre; Chaminade, Jean-Pierre; Fouassier, Claude

    2001-01-01

    A new type of lithium rare earth oxyborate of formula Li2Ln5O4(BO3)3 (Ln=Yb, Lu) has been discovered in the ternary phase diagrams Li2O-Ln2O3-B2O3. Single crystals of Li2Yb5O4(BO3)3 were grown by the flux method. The structure of this oxyborate was solved from a data collection with a four circle automatic diffractometer and with MoKα radiation. The cell is monoclinic (space group P21/m, Z=2) with a=10.095(2) Å, b=3.519(2) Å, c=15.647(11) Å, β=105.45(3)°, V=535.7(5) Å-3. Refinement of 86 parameters using 3298 independent reflections having intensity I>2σ(I) led to R=0.037 (wR=0.091). The structure of Li2Yb5O4(BO3)3 is made up of a bidimensional framework of edge or corner-sharing YbO7 polyhedra parallel to the (10overline1) plane and connected by three-coordinated boron atoms and lithium ions. It can also be described as a bidimensional assembly of OYb4 tetrahedra, ((Yb10O8)14+)n, separated by borate groups and lithium coordination polyhedra forming ribbons, ((Li4B6O18)14-)n, along the b direction. The presence of oxygen atoms sharing only Yb polyhedra justifies the oxyborate label.

  9. Microbial Hydroxylation of 5-Anilino-1,2,3,4-Thiatriazole

    PubMed Central

    Theriault, Robert J.; Longfield, Thomas H.

    1973-01-01

    Two hundred eighty-five fungi, including 100 basidiomycetes and 35 yeasts, 75 actinomycetes, and 40 bacteria were screened for their ability to convert 5-anilino-1,2,3,4-thiatriazole (AT) to 5-(p-hydroxyanilino)-1,2,3,4-thiatriazole (p-HT). Eleven cultures were found that formed p-HT, which was isolated and whose structure was determined. Aspergillus tamarii NRRL 3280 formed 8.6 g of p-HT/liter from 10 g of AT/liter (78.9% conversion) in shaken flasks and 4.57 g of p-HT/liter from 6 g of AT/liter (69.8% conversion) in 30-liter fermentors. Washed cells of A. tamarii NRRL 3280 also carried out this conversion. 5-(o-hydroxyanilino)-1,2,3,4-thiatriazole (o-HT) was identified as a second product formed by Aspergillus terreus NRRL 1960. PMID:4699219

  10. Down-Regulation of Porcine Heart Diaphorase Reactivity by Trimanganese Hexakis(3,5-Diisopropylsalicylate), Mn(3)(3,5-DIPS)6, and Down-Regulation of Nitric Oxide Synthase Reactivity by Mn(3)(3,5-DIPS)(6) and Cu(II)(2)(3,5-DIPS)(4).

    PubMed

    Booth, B L; Pitters, E; Mayer, B; Sorenson, J R

    1999-01-01

    Purposes of this work were to examine the plausible down-regulation of porcine heart diaphorase (PHD) enzyme reactivity and nitric oxide synthase (NOS) enzyme reactivity by trimanganese hexakis(3,5-diisopropylsalicylate), [Mn(3)(3,5-DIPS)(6)] as well as dicopper tetrakis(3,5- diisopropylsalicylate, [Cu(II)(2)(3,5-DIPS)(4)] as a mechanistic accounting for their pharmacological activities.Porcine heart disease was found to oxidize 114 muM reduced nicotinamide-adenine- dinucleotide-'(3)-phosphate (NADPH) with a corresponding reduction of an equivalent concentration of 2,6-dichlorophenolindophenol (DCPIP). As reported for Cu(II)(2) (3,5-DIPS)(4), addition of Mn(3)(3,5-DIPS)(6) to this reaction mixture decreased the reduction of DCPIP without significantly affecting the oxidation of NADPH. The concentration of Mn(3)(3,5-DIPS)(6) that produced a 50% decrease in DCPIP reduction (IC(50)) was found to be 5muM. Mechanistically, this inhibition of DCPIP reduction with ongoing NADPH oxidation by PHD was found to be due to the ability of Mn(3)(3,5-DIPS)(6) to serve as a catalytic electron acceptor for reduced PHD as had been reported for Cu(II)(2)(3,5-DIPS)(4). This catalytic decrease in reduction of DCPIP by Mn(3)(3,5-DIPS)(6) was enhanced by the presence of a large concentration of DCPIP and decreased by the presence of a large concentration of NADPH, consistent with what had been observed for the activity of Cu(II)(2)(3,5-DIPS)(4)Oxidation of NADPH by PHD in the presence of Mn(3)(3,5-DIPS)(6) and the absence of DCPIP was linearly related to the concentration of added Mn(3)(3,5-DIPS)(6) through the concentration range of 2.4 muM to 38muM with a 50% recovery of NADPH oxidation by PHD at a concentration of 6 muM Mn(3)(3,5-DIPS)(6)Conversion of [(3)H] L-Arginine to [(3)H] L-Citrulline by purified rat brain nitric oxide synthase (NOS) was decreased in a concentrated related fashion with the addition of Mn(3)(3,5-DIPS)(6) as well as Cu(II)(2)(3,5-DIPS)(4) which is an extention of

  11. Influence of the Torsion Angle in 3,3'-Dimethyl-2,2'-bipyridine on the Intermediate Valence of Yb in (C5Me5)2 Yb(3,3'-Me2-bipy)

    SciTech Connect

    Nocton, Grégory; Booth, Corwin H.; Maron, Laurent; Andersen, Richard A.

    2014-06-26

    The synthesis and X-ray crystal structures of Cp-2*Yb(3,3'-Me(2)bipy) and [Cp-2 Yb(3,3'-Me(2)bipy)][Cp-2 YbCl1.6I0.4]center dot CH2Cl2 are described. In both complexes, the NCCN torsion angles are approximately 40 degrees. The temperature-independent value of n(f) of 0.17 shows that the valence of ytterbium in the neutral adduct is multiconfigurational, in reasonable agreement with a CASSCF calculation that yields a n(f) value of 0.27; that is, the two configurations in the wave function are f(13)(pi(1))(1) and f(14)(pi(1))(0) in a ratio of 0.27:0.73, respectively, and the open-shell singlet lies 0.28 eV below the triplet state (n(f) accounts for f-hole occupancy; that is, n(f) = 1 when the configuration is f(13) and n(f) = 0 when the configuration is f(14)). A correlation is outlined between the value of nf and the individual ytterbocene and bipyridine fragments such that, as the reduction potentials of the ytterbocene cation and the free x,x'-R-2-bipy ligands approach each other, the value of nf and therefore the f(13):f(14) ratio reaches a maximum; conversely, the ratio is minimized as the disparity increases.

  12. Synthesis and stability of xenon oxides Xe2O5 and Xe3O2 under pressure.

    PubMed

    Dewaele, Agnès; Worth, Nicholas; Pickard, Chris J; Needs, Richard J; Pascarelli, Sakura; Mathon, Olivier; Mezouar, Mohamed; Irifune, Tetsuo

    2016-08-01

    The noble gases are the most inert group of the periodic table, but their reactivity increases with pressure. Diamond-anvil-cell experiments and ab initio modelling have been used to investigate a possible direct reaction between xenon and oxygen at high pressures. We have now synthesized two oxides below 100 GPa (Xe2O5 under oxygen-rich conditions, and Xe3O2 under oxygen-poor conditions), which shows that xenon is more reactive under pressure than predicted previously. Xe2O5 was observed using X-ray diffraction methods, its structure identified through ab initio random structure searching and confirmed using X-ray absorption and Raman spectroscopies. The experiments confirm the recent prediction of Xe3O2 as a stable xenon oxide under high pressure. Xenon atoms adopt mixed oxidation states of 0 and +4 in Xe3O2 and +4 and +6 in Xe2O5. Xe3O2 and Xe2O5 form extended networks that incorporate oxygen-sharing XeO4 squares, and Xe2O5 additionally incorporates oxygen-sharing XeO5 pyramids. Other xenon oxides (XeO2, XeO3) are expected to form at higher pressures. PMID:27442284

  13. Synthesis and stability of xenon oxides Xe2O5 and Xe3O2 under pressure

    NASA Astrophysics Data System (ADS)

    Dewaele, Agnès; Worth, Nicholas; Pickard, Chris J.; Needs, Richard J.; Pascarelli, Sakura; Mathon, Olivier; Mezouar, Mohamed; Irifune, Tetsuo

    2016-08-01

    The noble gases are the most inert group of the periodic table, but their reactivity increases with pressure. Diamond-anvil-cell experiments and ab initio modelling have been used to investigate a possible direct reaction between xenon and oxygen at high pressures. We have now synthesized two oxides below 100 GPa (Xe2O5 under oxygen-rich conditions, and Xe3O2 under oxygen-poor conditions), which shows that xenon is more reactive under pressure than predicted previously. Xe2O5 was observed using X-ray diffraction methods, its structure identified through ab initio random structure searching and confirmed using X-ray absorption and Raman spectroscopies. The experiments confirm the recent prediction of Xe3O2 as a stable xenon oxide under high pressure. Xenon atoms adopt mixed oxidation states of 0 and +4 in Xe3O2 and +4 and +6 in Xe2O5. Xe3O2 and Xe2O5 form extended networks that incorporate oxygen-sharing XeO4 squares, and Xe2O5 additionally incorporates oxygen-sharing XeO5 pyramids. Other xenon oxides (XeO2, XeO3) are expected to form at higher pressures.

  14. The reactions of 2-ethoxymethylidene-3-oxo esters and their analogues with 5-aminotetrazole as a way to novel azaheterocycles

    PubMed Central

    Burgart, Yanina V; Ezhikova, Marina A; Kodess, Mikhail I; Saloutin, Viktor I

    2015-01-01

    Summary The interaction of 2-ethoxymethylidene-3-oxo esters and their analogues with 5-aminotetrazole is an efficient synthetic approach to novel azaheterocycles. 2-Ethoxymethylidene-3-oxo esters bearing alkyl substituents react with 5-aminotetrazole to form ethyl 2-azido-4-alkylpyrimidine-5-carboxylates which are capable of subsequent nucleophilic substitution. The use of diethyl 2-ethoxymethylidenemalonate in this reaction resulted in ethyl 7-hydroxytetrazolo[1,5-a]pyrimidine-6-carboxylate, while ethyl 2-ethoxymethylidenecyanoacetate yielded 5-[2,6-diamino-3,5-bis(ethoxycarbonyl)pyridinium-1-yl]tetrazol-1-ide through an alternative pathway. Ethyl 2-benzoyl-3-ethoxyprop-2-enoate reacted with 5-aminotetrazole by two reaction routes to form ethyl 2-benzoyl-3-(1H-tetrazol-5-ylamino)prop-2-enoate and ethyl 7-(1-ethoxy-1,3-dioxo-3-phenylpropan-2-yl)-5-phenyl-4,7-dihydrotetrazolo[1,5-a]pyrimidine-6-carboxylate. PMID:25977712

  15. Crystal structure of the ternary silicide Gd2Re3Si5

    PubMed Central

    Fedyna, Vitaliia; Kozak, Roksolana; Gladyshevskii, Roman

    2014-01-01

    A single crystal of the title compound, the ternary silicide digadolinium trirhenium penta­silicide, Gd2Re3Si5, was isolated from an alloy of nominal composition Gd20Re30Si50 synthesized by arc melting and investigated by X-ray single-crystal diffraction. Its crystal structure belongs to the U2Mn3Si5 structure type. All atoms in the asymmetric lie on special positions. The Gd site has site symmetry m..; the two Mn atoms have site symmetries m.. and 2.22; the three Si atoms have site symmetries m.., ..2 and 4.. . The coordination polyhedra of the Gd atoms have 21 vertices, while those of the Re atoms are cubo­octa­hedra and 13-vertex polyhedra. The Si atoms are arranged as tricapped trigonal prisms, bicapped square anti­prisms, or 11-vertex polyhedra. The crystal structure of the title compound is also related to the structure types CaBe2Ge2 and W5Si3. It can be represented as a stacking of Gd-centred polyhedra of composition [GdSi9]. The Re atoms form infinite chains with an Re—Re distance of 2.78163 (5) Å and isolated squares with an Re—Re distance of 2.9683 (6) Å. PMID:25552967

  16. Crystal structure of the ternary silicide Gd2Re3Si5.

    PubMed

    Fedyna, Vitaliia; Kozak, Roksolana; Gladyshevskii, Roman

    2014-12-01

    A single crystal of the title compound, the ternary silicide digadolinium trirhenium penta-silicide, Gd2Re3Si5, was isolated from an alloy of nominal composition Gd20Re30Si50 synthesized by arc melting and investigated by X-ray single-crystal diffraction. Its crystal structure belongs to the U2Mn3Si5 structure type. All atoms in the asymmetric lie on special positions. The Gd site has site symmetry m..; the two Mn atoms have site symmetries m.. and 2.22; the three Si atoms have site symmetries m.., ..2 and 4.. . The coordination polyhedra of the Gd atoms have 21 vertices, while those of the Re atoms are cubo-octa-hedra and 13-vertex polyhedra. The Si atoms are arranged as tricapped trigonal prisms, bicapped square anti-prisms, or 11-vertex polyhedra. The crystal structure of the title compound is also related to the structure types CaBe2Ge2 and W5Si3. It can be represented as a stacking of Gd-centred polyhedra of composition [GdSi9]. The Re atoms form infinite chains with an Re-Re distance of 2.78163 (5) Å and isolated squares with an Re-Re distance of 2.9683 (6) Å. PMID:25552967

  17. Phosphorylation and 14-3-3 binding of Arabidopsis trehalose-phosphate synthase 5 in response to 2-deoxyglucose.

    PubMed

    Harthill, Jean E; Meek, Sarah E M; Morrice, Nick; Peggie, Mark W; Borch, Jonas; Wong, Barry H C; Mackintosh, Carol

    2006-07-01

    Trehalose-6-phosphate is a 'sugar signal' that regulates plant metabolism and development. The Arabidopsis genome encodes trehalose-6-phosphate synthase (TPS) and trehalose-6-phosphatase (TPP) enzymes. It also encodes class II proteins (TPS isoforms 5-11) that contain both TPS-like and TPP-like domains, although whether these have enzymatic activity is unknown. In this paper, we show that TPS5, 6 and 7 are phosphoproteins that bind to 14-3-3 proteins, by using 14-3-3 affinity chromatography, 14-3-3 overlay assays, and by co-immunoprecipitating TPS5 and 14-3-3 isoforms from cell extracts. GST-TPS5 bound to 14-3-3s after in vitro phosphorylation at Ser22 and Thr49 by either mammalian AMP-activated protein kinase (AMPK) or partially purified plant Snf1-related protein kinase 1 (SnRK1s). Dephosphorylation of TPS5, or mutation of either Ser22 or Thr49, abolished binding to 14-3-3s. Ser22 and Thr49 are both conserved in TPS5, 7, 9 and 10. When GST-TPS5 was expressed in human HEK293 cells, Thr49 was phosphorylated in response to 2-deoxyglucose or phenformin, stimuli that activate the AMPK via the upstream kinase LKB1. 2-deoxyglucose stimulated Thr49 phosphorylation of endogenous TPS5 in Arabidopsis cells, whereas phenformin did not. Moreover, extractable SnRK1 activity was increased in Arabidopsis cells in response to 2-deoxyglucose. The plant kinase was inactivated by dephosphorylation and reactivated by phosphorylation with human LKB1, indicating that elements of the SnRK1/AMPK pathway are conserved in Arabidopsis and human cells. We hypothesize that coordinated phosphorylation and 14-3-3 binding of nitrate reductase (NR), 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (F2KP) and class II TPS isoforms mediate responses to signals that activate SnRK1. PMID:16771775

  18. Synergistic effect of 2,2',4,4',5,5'-hexachlorobiphenyl and 2,3,7,8-tetrachlorodibenzo-p-dioxin on hepatic porphyrin levels in the rat.

    PubMed Central

    van Birgelen, A P; Fase, K M; van der Kolk, J; Poiger, H; Brouwer, A; Seinen, W; van den Berg, M

    1996-01-01

    We studied the effect of polychlorinated biphenyls (PCBs) on hepatic porphyrin accumulation in female Sprague-Dawley rats by feeding them diets containing 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,2',4,4',5,5'-hexachlorobiphenyl (PCB 153), 2,3,3',4,4',5-hexachlorobiphenyl (PCB 156), 3,3',4,4',5-pentachlorobiphenyl (PCB 126), or combinations of the single PCB congeners with TCDD for 13 weeks. A dose-dependent increase in hepatic porphyrin accumulation occurred after TCDD, PCB 126, or PCB 156 administration, reaching maximal levels of about twice control values. The lowest dose levels for which a significant increase in hepatic porphyrin accumulation was found were 0.7 microgram TCDD/kg diet, 50 micrograms PCB 126/kg diet, or 6 mg PCB 156/kg diet. These doses are equivalent to 47 ng TCDD/kg/day, 3.2 micrograms PCB 126/kg/day, and 365 micrograms PCB 156/kg/day. Relative potencies for hepatic porphyrin accumulation, using TCDD as a reference, ranged from 0.015 to 0.06 for PCB 126 and from 0.0001 to 0.0003 for PCB 156. CYP1A2 activities significantly correlated with hepatic porphyrin levels, with coefficients of 0.629, 0.483, or 0.808 for TCDD, PCB 126, or PCB 156, respectively. Administration of PCB 153 alone did not result in hepatic porphyrin accumulation. Co-administration of PCB 153 and TCDD revealed a strong synergistic effect on porphyrin accumulation (about 800 times control levels). This synergistic effect was significant in rats fed diets containing any combination of PCB 153 with TCDD. Uroporphyrin III and heptacarboxylic porphyrin were accumulated in porphyrinogenic livers. These results suggest that TCDD induction of CYP1A2 may be involved, leading to oxidation of uroporphyrinogen III to uroporphyrin III, in combination with an increase in delta-aminolevulinic acid synthetase induced by PCB 153. Under porphyrinogenic conditions, an inhibitor of CYP1A2 activity may also be formed. The interactive effects on porphyrin accumulation after co

  19. Molecular motions in a novel ferroelectric crystal (CH 3NH 3) 5Bi 2Br 11 studied by NMR

    NASA Astrophysics Data System (ADS)

    Piekara-Sady, L.; Jakubas, R.; Piślewski, N.

    1989-11-01

    The temperature dependence of the 1H relaxation times T1, T1 ρ and T1 D were studied in the ferroelectric (CH 3NH 3) 5Bi 2Br 11. Three kinds of motions of the methylammonium cation, i.e. (1) rotations of the CH 3 and NH 3 groups about C 3 axis, (2) reorientation of the whole cation about C 3 axis forming an angle α = 13° with the C 3 axis of NH 3 and CH 3 groups, (3) 180° flip motion of the methylammonium cation, have been observed separately. The small activation energies of these motions imply that the cations experience a weak crystal field.

  20. Synthesis of divinyl derivatives of 5-substituted 1,2,4-triazole-3-thiones

    SciTech Connect

    Trzhtsinskaya, B.V.; Rudakova, E.V.; Afonin, A.V.; Pertsikov, B.Z.; Mansurov, Yu.A.; Aksenov, V.P.

    1987-01-20

    The authors have previously described the synthesis of two divinyl derivatives of unsubstituted triazolethione. In order to expand the range of such compounds, they studied the reaction of 5-methyl- (I), 5-phenyl- (II), and 5-..cap alpha..-furyl-1,2,4-triazole-3-thione (III) with acetylene. Triazoles (I) and (III) in the presence of alkali add one acetylene molecule. An increase in the reaction time yields the product of the addition of two acetylene molecules to (I) in yields up to 50%. The substitution of the alkaline catalyst by CuCl facilitates the formation of divinyl derivatives. However, the use of CuCl in this case led to a decrease in the yield of the desired product. N-Vinyl-3-vinylthio-5-methyl-1,2,4-triazoles were obtained in yields up to 64% in the presence of cadmium acetate. On the other hand, the use of CuCl as the catalyst facilitates the synthesis of N-vinyl-3-vinylthio-5-phenyl- and N-vinyl-3-vinylthio-5-..cap alpha..-furyl-1,2,4-triazoles.

  1. 2 μm fluorescence of Ho3+:5I7 → 5I8 transition sensitized by Er3+ in tellurite germanate glasses

    NASA Astrophysics Data System (ADS)

    Chen, Rong; Tian, Ying; Li, Bingpeng; Wang, Fengchao; Jing, Xufeng; Zhang, Junjie; Xu, Shiqing

    2015-11-01

    This paper investigated the mid-infrared luminescence properties of Er3+/Ho3+ co-doped tellurite germanate glass at 2 μm pumped by 980 nm. Thermal stability of the system, absorption spectra and fluorescence spectra of the Er3+/Ho3+ co-doped glass sample were measured. Besides, the absorption spectra of the Ho3+ singly doped sample was measured. According to the measured absorption spectra and the Judd-Ofelt theory, the Judd-Ofelt intensity parameters Ωt (t = 2, 4, 6), spontaneous radiative transition probability, branching ratio and lifetime of Ho3+ were calculated. And the upconversion emission in Er3+ doped and Er3+/Ho3+ co-doped tellurite germanate glasses pumped by 980 nm have been investigated. Then the spectroscopic properties and possible energy transfer mechanisms between Ho3+ and Er3+ ions were discussed in detail. Meanwhile, the FWHM (146 nm), σepeak × FWHM (659.92 cm3) and emission cross section (4.52 × 10-21 cm2) of 5I8 → 5I7 transition of Ho3+ were obtained, respectively. The results indicate that Er3+/Ho3+ co-doped tellurite germanate glass is a promising host material for 2 μm solid laser.

  2. Biodegradation of the Hexahydro-1,3,5-Trinitro-1,3,5-Triazine Ring Cleavage Product 4-Nitro-2,4-Diazabutanal by Phanerochaete chrysosporium

    PubMed Central

    Fournier, Diane; Halasz, Annamaria; Spain, Jim; Spanggord, Ronald J.; Bottaro, Jeffrey C.; Hawari, Jalal

    2004-01-01

    Initial denitration of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by Rhodococcus sp. strain DN22 produces CO2 and the dead-end product 4-nitro-2,4-diazabutanal (NDAB), OHCNHCH2NHNO2, in high yield. Here we describe experiments to determine the biodegradability of NDAB in liquid culture and soils containing Phanerochaete chrysosporium. A soil sample taken from an ammunition plant contained RDX (342 μmol kg−1), HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine; 3,057 μmol kg−1), MNX (hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine; 155 μmol kg−1), and traces of NDAB (3.8 μmol kg−1). The detection of the last in real soil provided the first experimental evidence for the occurrence of natural attenuation that involved ring cleavage of RDX. When we incubated the soil with strain DN22, both RDX and MNX (but not HMX) degraded and produced NDAB (388 ± 22 μmol kg−1) in 5 days. Subsequent incubation of the soil with the fungus led to the removal of NDAB, with the liberation of nitrous oxide (N2O). In cultures with the fungus alone NDAB degraded to give a stoichiometric amount of N2O. To determine C stoichiometry, we first generated [14C]NDAB in situ by incubating [14C]RDX with strain DN22, followed by incubation with the fungus. The production of 14CO2 increased from 30 (DN22 only) to 76% (fungus). Experiments with pure enzymes revealed that manganese-dependent peroxidase rather than lignin peroxidase was responsible for NDAB degradation. The detection of NDAB in contaminated soil and its effective mineralization by the fungus P. chrysosporium may constitute the basis for the development of bioremediation technologies. PMID:14766596

  3. Biodegradation of the hexahydro-1,3,5-trinitro-1,3,5-triazine ring cleavage product 4-nitro-2,4-diazabutanal by Phanerochaete chrysosporium.

    PubMed

    Fournier, Diane; Halasz, Annamaria; Spain, Jim; Spanggord, Ronald J; Bottaro, Jeffrey C; Hawari, Jalal

    2004-02-01

    Initial denitration of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by Rhodococcus sp. strain DN22 produces CO2 and the dead-end product 4-nitro-2,4-diazabutanal (NDAB), OHCNHCH2NHNO2, in high yield. Here we describe experiments to determine the biodegradability of NDAB in liquid culture and soils containing Phanerochaete chrysosporium. A soil sample taken from an ammunition plant contained RDX (342 micromol kg(-1)), HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine; 3,057 micromol kg(-1)), MNX (hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine; 155 micromol kg(-1)), and traces of NDAB (3.8 micromol kg(-1)). The detection of the last in real soil provided the first experimental evidence for the occurrence of natural attenuation that involved ring cleavage of RDX. When we incubated the soil with strain DN22, both RDX and MNX (but not HMX) degraded and produced NDAB (388 +/- 22 micromol kg(-1)) in 5 days. Subsequent incubation of the soil with the fungus led to the removal of NDAB, with the liberation of nitrous oxide (N2O). In cultures with the fungus alone NDAB degraded to give a stoichiometric amount of N2O. To determine C stoichiometry, we first generated [14C]NDAB in situ by incubating [14C]RDX with strain DN22, followed by incubation with the fungus. The production of 14CO2 increased from 30 (DN22 only) to 76% (fungus). Experiments with pure enzymes revealed that manganese-dependent peroxidase rather than lignin peroxidase was responsible for NDAB degradation. The detection of NDAB in contaminated soil and its effective mineralization by the fungus P. chrysosporium may constitute the basis for the development of bioremediation technologies. PMID:14766596

  4. Crystal Field Excitations in the Breathing Pyrochlore Antiferromagnet Ba3Yb2Zn5O11

    NASA Astrophysics Data System (ADS)

    Haku, Tendai; Soda, Minoru; Sera, Masakazu; Kimura, Kenta; Itoh, Shinichi; Yokoo, Tetsuya; Masuda, Takatsugu

    2016-03-01

    Inelastic neutron scattering measurement is performed on the breathing pyrochlore antiferromagnet Ba3Yb2Zn5O11. The observed dispersionless excitations are explained on the basis of a crystalline electric field (CEF) Hamiltonian of the Kramers ion Yb3+, the local symmetry of which exhibits C3v point group symmetry. The magnetic susceptibility previously reported is consistently reproduced by the energy scheme of the CEF excitations. The obtained wave functions of the ground-state Kramers doublet exhibit planer-type anisotropy. The result demonstrates that Ba3Yb2Zn5O11 is an experimental realization of a breathing pyrochlore antiferromagnet with a pseudospin S = 1/2 having easy-plane anisotropy.

  5. Ceramic oxide reactions with V2O5 and SO3

    NASA Technical Reports Server (NTRS)

    Jones, R. L.; Williams, C. E.

    1985-01-01

    Ceramic oxides are not inert in combustion environments, but can react with, inter alia, SO3, and Na2SO4 to yield low melting mixed sulfate eutectics, and with vanadium compounds to produce vanadates. Assuming ceramic degradation to become severe only when molten phases are generated in the surface salt (as found for metallic hot corrosion), the reactivity of ceramic oxides can be quantified by determining the SO3 partial pressure necessary for molten mixed sulfate formation with Na2SO3. Vanadium pentoxide is an acidic oxide that reacts with Na2O, SO3, and the different ceramic oxides in a series of Lux-Flood type of acid-base displacement reactions. To elucidate the various possible vanadium compound-ceramic oxide interactions, a study was made of the reactions of a matrix involving, on the one axis, ceramix oxides of increasing acidity, and on the other axis, vanadium compounds of increasing acidity. Resistance to vanadium compound reaction increased as the oxide acidity increased. Oxides more acidic than ZrO2 displaced V2O5. Examination of Y2O3- and CeO2-stabilized ZrO2 sintered ceramics which were degraded in 700 C NaVO3 has shown good agreement with the reactions predicted above, except that the CeO2-ZrO2 ceramic appears to be inexplicably degraded by NaVO3.

  6. Crystal structures of two 6-(2-hy-droxy-benzo-yl)-5H-thia-zolo[3,2-a]pyrimidin-5-ones.

    PubMed

    Gomes, Ligia R; Low, John Nicolson; Cagide, Fernando; Borges, Fernanda

    2015-07-01

    The title compounds, 6-(2-hy-droxy-benz-yl)-5H-thia-zolo[3,2-a]pyrimidin-5-one, C13H8N2O3S, (1), and 6-(2-hy-droxy-benz-yl)-3-methyl-5H-thia-zolo[3,2-a]pyrimidin-5-one, C14H10N2O3S, (2), were synthesized when a chromone-3-carb-oxy-lic acid, activated with (benzotriazol-1-yl-oxy)tripyrrolidinyl-phospho-nium hexa-fluorido-phosphate (PyBOP), was reacted with a primary heteromamine. Instead of the expected amidation, the unusual title thia-zolo-pyrimidine-5-one derivatives were obtained serendipitously and a mechanism of formation is proposed. Both compounds present an intra-molecular O-H⋯O hydrogen bond, which generates an S(6) ring. The dihedral angles between the heterocyclic moiety and the 2-hydroxybenzoyl ring are 55.22 (5) and 46.83 (6)° for (1) and (2), respectively. In the crystals, the mol-ecules are linked by weak C-H⋯O hydrogen bonds and π-π stacking inter-actions. PMID:26279863

  7. Novel method of synthesis of 5''-phosphate 2'-O-ribosyl-ribonucleosides and their 3'-phosphoramidites.

    PubMed

    Chmielewski, Marcin K; Markiewicz, Wojciech T

    2013-01-01

    Synthesis of 5''-phosphate 2'-O-ribosylribonucleosides [Nr(p)] of four common ribonucleosides, and 3'-phosphoramidites of 5''-phosphate 2'-O-ribosyladenosine and 2'-O-ribosylguanosine using the H-phosphonate chemistry is described. An additional ring protected by benzoyl groups was incorporated into the main ribosyl ring in the reaction with 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribofuranose in the presence of SnCl4. The obtained 2'-O-ribosylribonucleosides (Nr) were applied in the subsequent transformations with selective deprotection. Ethanolamine was applied as a very convenient reagent for selective removal of benzoyl groups. Additionally, the tetraisopropyldisiloxane-1,3-diyl (TIPDSi) group was found to be stable under these deprotection conditions. Thus, the selectively deprotected 5''-hydroxyl group of Nr was transformed into an H-phosphonate monoester which was found to be stable under the following conditions: the removal of the TIPDSi group with triethylammonium fluoride and the dimethoxytritylation of the 5''-hydroxyl function. The 5''-H-phosphonate of Nr precursors was easily transformed to the corresponding dicyanoethyl 5''-O-phosphotriesters before phosphitylation, which gave 3'-phosphoramidite units of Nr(p) in high yield. The derived phosphoramidite units were used in an automated oligonucleotide synthesizer to produce dimer Ar(p)T via the phosphoramidite approach. The obtained products were fully deprotected under standard deprotection conditions giving dimers with a 5''-phosphate monoester function. Application of an alkaline phosphatase to prove the presence of an additional phosphate group was described. PMID:24352053

  8. Absolute configuration of (1S,2S)-3-methyl-2-phenyl-2,3-dihydro­thia­zolo[2,3-b]quinazolin-5-one

    PubMed Central

    Ghorab, Mostafa. M.; Al-Said, Mansour. S.; Abdel-Kader, Maged. S.; Hemamalini, Madhukar; Fun, Hoong-Kun

    2012-01-01

    The absolute structure of the molecule in the crystal of the title compound, C17H14N2OS, was determined by the refinement of the Flack parameter to 0.0 (2) based on 1011 Friedel pairs. The quinazoline ring is essentially planar, with a maximum deviation of 0.037 (2) Å. The thia­zole ring is distorted from planarity [maximum deviation = 0.168 (2) Å] and adopts a slightly twisted envelope conformation, with the C atom as the flap atom. The central thia­zole ring makes dihedral angles of 7.01 (8) and 76.80 (10)° with the quinazoline and phenyl rings, respectively. The corresponding angle between the quinazoline and phenyl rings is 3.74 (9)°. In the crystal, there are no classical hydrogen bonds but stabilization is provided by weak C—H⋯π inter­actions, involving the centroids of the phenyl rings. PMID:22589992

  9. JCMT HARP CO 3-2 observations of molecular outflows in W5

    NASA Astrophysics Data System (ADS)

    Ginsburg, Adam; Bally, John; Williams, Jonathan P.

    2011-12-01

    New James Clerk Maxwell Telescope (JCMT) HARP CO 3-2 observations of the W5 star forming complex are presented, totalling an area of ˜12 000 arcmin2 with sensitivity better than 0.1 K per 0.4 km s-1 channel. We discovered 55 CO outflow candidates, of which 40 are associated with W5 and 15 are more distant than the Perseus arm. Most of the outflows are located on the periphery of the W5 H II region. However, two outflow clusters are >5 pc from the ionization fronts, indicating that their driving protostars formed without directly being triggered by the O-stars in W5. We compare the derived outflow properties to those in Perseus and find that the total W5 outflow mass is surprisingly low given the cloud masses. The outflow mass deficiency in the more massive W5 cloud [M(H2) ˜ 5 × 104 M⊙] can be explained if ionizing radiation dissociates molecules as they break out of their host cloud cores. Although CO J = 3-2 is a good outflow tracer, it is likely to be a poor mass tracer because of sub-thermal line excitation and high opacity, which may also contribute to the outflow mass discrepancy. It is unlikely that outflows could provide the observed turbulent energy in the W5 molecular clouds even accounting for undetected outflow material. Many cometary globules have been observed with velocity gradients from head to tail, displaying strong interaction with the W5 H II region and exhibiting signs of triggered or revealed star formation in their heads. Because it is observed face-on, W5 is an excellent region to study feedback effects, both positive and negative, of massive stars on star formation.

  10. Diels-Alder Synthesis of endo-cis-N-phenylbicyclo[2.2.2]oct-5-en-2,3-dicarboximide

    ERIC Educational Resources Information Center

    Baar, Marsha R.; Wustholz, Kristin

    2005-01-01

    A study investigated the Diels-Alder synthesis of endo-cis-N-phenylbicyclo [2.2.2]oct-5-en-2,3-dicarboximide. The amount of time taken by a reaction between the 1,3-cyclohexadiene and N-phenylmaleimide at room temperature and also whether the desired cycloadduct would precipitate directly from the reaction mixture was examined.

  11. Pulmonary tolerance in man to continuous oxygen exposure at 3.0, 2.5, 2.0, and 1.5 ATA in Predictive Studies V

    NASA Technical Reports Server (NTRS)

    Clark, J. M.; Gelfand, R.; Flores, N. D.; Lambertsen, C. J.; Pisarello, J. B.

    1987-01-01

    Oxygen effects on pulmonary function were measured in normal, resting men who breathed oxygen continuously at 3.0, 2.5, 2.0, and 1.5 ATA to predefined limits of CNS, cardiac, or pulmonary tolerance. Rates of pulmonary symptom intensification and decrease in vital capacity (VC) increased progressively with elevation of inspired oxygen pressure. Although VC decrements occurred concurrently with symptoms, the lung volume changes became prominent when symptoms were still mild. The observed effects were consistent with the interpretation that small airway function is impaired more selectively by oxygen exposure at 3.0 and 2.5 ATA than by exposure at 2.0 and 1.5 ATA. Despite similar VC changes after oxygen exposure at 2.0 ATA for nearly 10 hr and exposure at 1.5 ATA for almost 18 hr, the 2.0 ATA exposure caused greater impairment of pulmonary function and required a longer recovery period.

  12. Magnetic properties of Fe73.5Cu1Nb3-xUxSi13.5B9 (x = 1, 2, 3) nanocrystalline alloys

    NASA Astrophysics Data System (ADS)

    Kollár, P.; Füzer, J.; Matta, P.; Švec, T.; Konč, M.

    1996-05-01

    The influence of uranium content and annealing on the magnetic properties and Hall effect of Fe73.5Cu1Nb3-xUxSi13.5B9 (x = 1, 2, 3) nanocrystalline alloys prepared by melt spinning were investigated. Measurements of magnetic properties of surface layers confirmed higher concentration of uranium in the air-side surface layers than in the wheel-side layers.

  13. 5-(4-Hy-droxy-benzyl-idene)-2,2-dimethyl-1,3-dioxane-4,6-dione.

    PubMed

    Zeng, Wu-Lan

    2010-01-01

    The title compound, C(13)H(12)O(5), was prepared by the reaction of 2,2-dimethyl-1,3-dioxane-4,6-dione and 4-hy-droxy-benz-alde-hyde in ethanol. The 1,3-dioxane ring is in a distorted boat conformation. In the crystal, inversion dimers linked by pairs of O-H⋯O hydrogen bonds generate R(2) (2)(20) rings. PMID:21588666

  14. A novel glucose oxidase biosensor based on poly([2,2';5',2″]-terthiophene-3'-carbaldehyde) modified electrode.

    PubMed

    Guler, Muhammet; Turkoglu, Vedat; Kivrak, Arif

    2015-08-01

    In the study, the electrochemical behavior of glucose oxidase (GOx) immobilized on poly([2,2';5',2″]-terthiophene-3'-carbaldehyde) (poly(TTP)) modified glassy carbon electrode (GCE) was investigated. The biosensor (poly(TTP)/GOx/GCE) showed a pair of redox peaks in 0.1 M phosphate buffer (pH 7.4) solution in the absence of oxygen the co-substrate of GOx. In here, Poly(TTP)/GOx/GCE biosensor acts as the co-substrate instead of oxygen. Upon the addition of glucose, the reduction and oxidation peak currents increased until the active site of GOx was fully saturated with glucose. The apparent m was estimated 26.13 mM from Lineweaver-Burk graph. The biosensor displayed a good stability and bioactivity. The biosensor showed a high sensitivity (56.1 nA/mM), a linear range (from 0.5 to 20.15 mM), and a good reproducibility with 3.6% of relative standard deviation. In addition, the interference currents of glycin, ascorbic acid, histidine, uric acid, dopamine, arginine, and fructose on GOx biosensor were investigated. All that substances exhibited an interference current under 10%. It was not shown a marked difference between GOx biosensor and spectrophotometric measurement of glucose in serum examples. UV-visible spectroscopy and scanning electron microscopy (SEM) experiments of the biosensor were also performed. PMID:25934105

  15. Synthesis, structures, electrochemical studies and antioxidant activity of 5-aryl-4-oxo-3,4,5,8-tetrahydropyrido[2,3-d]pyrimidine-7-carboxylic acids

    NASA Astrophysics Data System (ADS)

    Quiroga, Jairo; Romo, Pablo E.; Ortiz, Alejandro; Isaza, José Hipólito; Insuasty, Braulio; Abonia, Rodrigo; Nogueras, Manuel; Cobo, Justo

    2016-09-01

    The synthesis of 5-aryl-4-oxo-3,4,5,8-tetrahydropyrido[2,3-d]pyrimidine-7-carboxylic acids 3 from the reaction of 6-aminopyrimidines 1 with arylidene derivatives of pyruvic acid 2 under microwave and ultrasound irradiation is described. The orientation of cyclization process was determined by NMR measurements. The methodology provides advantages such as high yields and friendly to the environment without the use of solvents. The antioxidant properties, DPPH free radical scavenging, ORAC, and anodic potential oxidation of the new pyridopyrimidines were studied.

  16. Mo5PB2: a new superconductor in the Cr5B3 structure type with Tc = 9.2 K

    NASA Astrophysics Data System (ADS)

    McGuire, Michael; Parker, David

    Superconductivity has been reported recently in several ternary silicide-borides adopting the tetragonal Cr5B3 structure type, including Nb5Si3-xBx, Mo5SiB2, and W5SiB2, with critical temperatures ranging from 5.8-7.8 K. Here we report superconductivity with Tc exceeding 9 K in the phosphorus-containing analogue Mo5PB2. We have synthesized polycrystalline samples of the compound, made measurements of electrical resistivity, magnetic susceptibility, and heat capacity, and performed first principles electronic structure calculations. The highest Tc values occur in slightly phosphorus rich samples, with composition near Mo5P1.1B1.9. Together with the measured properties, the calculations suggest the superconductivity in these materials may be multi-band. Research sponsored by the US Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division.

  17. 3-nitro-1,2,4-triazol-5-one: A less sensitive explosive

    DOEpatents

    Lee, Kien-Yin; Coburn, M.D.

    1987-01-30

    A less sensitive explosive, 3-nitro-1,2,4-triazol-5-one. The compound 3-nitro--1,2,4-triazol-5-one (NTO) has a crystal density of 1.93 g/cm/sup 3/ and calculated detonation velocity and pressure equivalent to those of RDX. It can be prepared in high yield from inexpensive starting materials in a safe synthesis. Results from initial small-scale sensitivity tests indicate that NTO is less sensitive than RDX and HMX in all respects. A 4.13 cm diameter, unconfined plate-dent test at 92% of crystal density gave the detonation pressure predicted for NTO by the BKW calculation. 3 tabs.

  18. Space station data system analysis/architecture study. Task 3: Trade studies, DR-5, volume 2

    NASA Technical Reports Server (NTRS)

    1985-01-01

    Results of a Space Station Data System Analysis/Architecture Study for the Goddard Space Flight Center are presented. This study, which emphasized a system engineering design for a complete, end-to-end data system, was divided into six tasks: (1); Functional requirements definition; (2) Options development; (3) Trade studies; (4) System definitions; (5) Program plan; and (6) Study maintenance. The Task inter-relationship and documentation flow are described. Information in volume 2 is devoted to Task 3: trade Studies. Trade Studies have been carried out in the following areas: (1) software development test and integration capability; (2) fault tolerant computing; (3) space qualified computers; (4) distributed data base management system; (5) system integration test and verification; (6) crew workstations; (7) mass storage; (8) command and resource management; and (9) space communications. Results are presented for each task.

  19. Mathematical study of the thermoluminescence process in K2YF5:Tb(3+).

    PubMed

    Kadari, Ahmed; Mostefa, Rabah; Marcazzó, Julián; Kadri, Dahane

    2015-12-01

    This paper presents results of studying the simulated thermoluminescence (TL) glow curve in potassium-yttrium double fluoride doped with trivalent optically active Tb(3+) ions (K2YF5:Tb(3+)). Samples have been irradiated with different doses (0.24, 2.4 and 24 Gy) of beta particles. Four trapping states and one kind of recombination-centre model have been used in this simulation. The activation energy and order of kinetics are determined using the general-order kinetic model. The results obtained using the authors' proposed models were tested and compared with the experimental glow curve of K2YF5:Tb(3+). The comparison has shown that the proposed model can predict more accurately and easily the behaviour of the TL glow curve at three different doses. PMID:25543131

  20. Preparation and properties of 3-amino-5-nitro-1,2,4-triazole

    SciTech Connect

    Lee, Kien-Yin; Storm, C.B.

    1990-10-01

    A novel method for the preparation of 3-amino-5-nitro-1,2,4-triazole (ANTA) has been invented. The yield of ANTA by selective reduction of the ammonium salt of 3,5-dinitro-1,2,4-triazole with hydrazine hydrate is 94% to 96% under mild reaction conditions. There is no volatile hydrazine present at the end of the reaction as it is isolated as hydrazine hydrochloride. ANTA, a potential insensitive explosive, has a crystal density of 1.82 g/cm{sup 3}, and a positive heat of formation ({Delta}H{sub f}) of 21.0 kcal/mol, and is thermally stable. The detonation velocity of ANTA, calculated at crystal density, is higher than that of triaminotrinitrobenzene. In addition to the preparation of ANTA, we have also synthesized a new hydrazinium salt of ANTA. 6 refs., 2 tabs.

  1. DETERMINATION OF 3,5,6-TRICHLORO-2-PYRIDINOL (TCP) BY ELISA

    EPA Science Inventory

    A sensitive, competitive enzyme-linked immunosorbent assay (ELISA) for 3,5,6-trichloro-2pyridinol (TCP) has been developed to quantitate parts per billion (ppb) amounts of the analyte in urine. TCP is a major metabolite and environmental degradation product of the insecticide c...

  2. Fuel compositions containing maleic derivatives of 2,5-dimercapto-1,3,4-thiadiazole

    SciTech Connect

    Karol, T.J.

    1989-11-14

    This patent describes a diesel fuel composition. It is characterized by improved wear properties. It comprises: a major portion of middle distillates boiling in the range of about 163{degrees}to 400{degrees}C. and a minor wear improving amount of a reaction product of a maleic compound and 2,5-dimercapto-1,3,4-thiadiazole.

  3. Vanadium Complex Derived from N'-(3-Bromo-5-chloro-2-hydroxybenzylidene) -3-methylbenzohydrazide: Synthesis, Crystal Structure and Biological Activity.

    PubMed

    Han, Zhen-Quan; Han, Shuang; Wang, Yuan

    2016-01-01

    Reaction of VO(acac)(2) with N'-(3-bromo-5-chloro-2-hydroxybenzylidene)-3-methylbenzohydrazide (H(2)L) in methanol afforded a new mononuclear vanadium(V) complex, [VOL(OMe)(MeOH)]. Structure of the complex has been characterized by physico-chemical methods and single-crystal X-ray diffraction. The complex crystallizes as the monoclinic space group P2(1)/c, with unit cell dimensions a = 13.1345(10) Å, b = 18.6279(14) Å, c = 7.8983(8) Å, β = 90.248(2)º, V = 1932.4(3) Å(3), Z = 4, R(1) = 0.0963, wR(2) = 0.2213, S = 1.113. X-ray analysis indicated that the V atom in the complex is in octahedral coordination. The insulin-like activity of the complex was studied. PMID:26970806

  4. Thermal and fragility studies on microwave synthesized K2O-B2O3-V2O5 glasses

    NASA Astrophysics Data System (ADS)

    Harikamalasree, Reddy, M. Sudhakara; Viswanatha, R.; Reddy, C. Narayana

    2016-05-01

    Glasses with composition xK2O-60B2O3-(40-x) V2O5 (15 ≤ x ≤ 39 mol %) was prepared by an energy efficient microwave method. The heat capacity change (ΔCp) at glass transition (Tg), width of glass transition (ΔTg), heat capacities in the glassy (Cpg) and liquid (Cpl) state for the investigated glasses were extracted from Modulated Differential Scanning Calorimetry (MDSC) thermograms. The width of glass transition is less than 30°C, indicating that these glasses belongs to fragile category. Fragility functions [NBO]/(Vm3Tg) and (ΔCp/Cpl)increases with increasing modifier oxide concentration. Increase in fragility is attributed to the increasing coordination of boron. Further, addition of K2O creates NBOs and the flow mechanism involves bond switching between BOs and NBOs. Physical properties exhibit compositional dependence and these properties increase with increasing K2O concentration. The observed variations are qualitatively analyzed.

  5. Metal Complexes of Dithiolate Ligands: 5,6-Dihydro-1,4-dithiin-2,3-dithiolato (dddt(2-)), 5,7-Dihydro-1,4,6-trithiin-2,3-dithiolato (dtdt(2-)), and 2-Thioxo-1,3-dithiole-4,5-dithiolato (dmit(2-)). Synthesis, Electrochemical Studies, Crystal and Electronic Structures, and Conducting Properties.

    PubMed

    Faulmann, Christophe; Errami, Ahmed; Donnadieu, Bruno; Malfant, Isabelle; Legros, Jean-Pierre; Cassoux, Patrick; Rovira, Carme; Canadell, Enric

    1996-06-19

    New precursors to potentially conductive noninteger oxidation state (NIOS) compounds based on metal complexes [ML(2)](n)()(-) [M = Ni, Pd, Pt; L = 5,6-dihydro-1,4-dithiin-2,3-dithiolato (dddt(2)(-)), 5,7-dihydro-1,4,6-trithiin-2,3-dithiolato (dtdt(2)(-)), and 2-thioxo-1,3-dithiole-4,5-dithiolato (dmit(2)(-)); n = 2, 1, 0] have been investigated. Complexes of the series (NR(4))[ML(2)] (R = Me, Et, Bu; L = dddt(2)(-), dtdt(2)(-)) have been isolated and characterized, and the crystal structure of (NBu(4))[Pt(dtdt)(2)] (1) has been determined {1 = C(24)H(44)NPtS(10), a = 12.064(2) Å, b = 17.201(3) Å, c = 16.878(2) Å, beta = 102.22(2) degrees, V = 3423(1) Å(3), monoclinic, P2(1)/n, Z = 4}. Oxidation of these complexes affords the corresponding neutral species [ML(2)](0). Another series of general formula (cation)(n)()[M(dmit)(2)] [cation = PPN(+), BTP(+), and (SMe(y)()Et(3)(-)(y)())(+) with y = 0, 1, 2, and 3, n = 2, 1, M = Ni, Pd] has also been studied. All of these (cation)(n)()[M(dmit)(2)] complexes have been isolated and characterized [with the exception of (cation)[Pd(dmit)(2)] for cation = (SMe(y)()Et(3)(-)(y)())(+)]. The crystal structures of (PPN)[Ni(dmit)(2)].(CH(3))(2)CO (2) and (SMeEt(2))[Ni(dmit)(2)] (3) have been determined {2 = C(45)H(36)NNiS(10)P(2)O, a = 12.310(2) Å, b = 13.328(3) Å, c = 15.850(3) Å, alpha = 108.19(3) degrees, beta = 96.64(2) degrees, gamma = 99.67(2) degrees, V = 2373(1) Å(3), triclinic, P&onemacr;, Z = 2; 3 = C(11)H(13)NiS(11), a = 7.171(9) Å, b = 17.802(3) Å, c = 16.251(3) Å, beta = 94.39(4) degrees, V = 2068(2) Å(3), monoclinic, P2(1)/n, Z = 4} NIOS salts derived from the preceding precursors were obtained by electrochemical oxidation. Electrochemical studies of the [M(dddt)(2)] complexes show that they may be used for the preparation of NIOS radical cation salts and [M(dddt)(2)][M'(dmit)(2)](x)() compounds, but not for the preparation of (cation)[M(dddt)(2)](z)() NIOS radical anion salts. The electrochemical oxidation of

  6. 5,5'-Di-tert-butyl-2,2'-dihydroxy-3,3'-methylenedibenzaldehyde and 6,6'-di-tert-butyl-8,8'-methylenebis(spiro[4H-1,3-benzodioxin-2,1'-cyclohexane]).

    PubMed

    Masci, Bernardo; Mortera, Stefano Levi; Seralessandri, Luca; Thuéry, Pierre

    2004-02-01

    Two related compounds containing p-tert-butyl-o-methylene-linked phenol or phenol-derived subunits are described, namely 5,5'-di-tert-butyl-2,2'-dihydroxy-3,3'-methylenedibenzaldehyde, C(23)H(28)O(4), (I), and 6,6'-di-tert-butyl-8,8'-methylenebis(spiro[4H-1,3-benzodioxin-2,1'-cyclohexane]), C(35)H(48)O(4), (II). Both compounds adopt a 'butterfly' shape, with the two phenol or phenol-derived O atoms in distal positions. Phenol and aldehyde groups in (I) are involved in intramolecular hydrogen bonds and the two dioxin rings in (II) are in distorted half-chair conformations. PMID:14767128

  7. Synthesis, characterization, and crystal structure of 2-iodo-3,4,5-trimethoxybenzoic acid

    NASA Astrophysics Data System (ADS)

    Kolev, Iliyan N.; Petrova, Svetlana P.; Nikolova, Rositsa P.; Dimowa, Louiza T.; Shivachev, Boris L.

    2013-02-01

    This work describes the synthesis of 2-iodo-3,4,5-trimethoxybenzoic acid. The combination of iodine and silver trifluoroacetate (AgTFA) reagents was used successfully for the iodination of 3,4,5-trimetoxybenzoic acid. To improve the efficiency of the synthetic process a significant modification on the experimental design was also performed. The main structural features of the obtained aryl iodide were investigated by a single crystal X-ray diffraction analysis, FTIR, 1H and 13C NMR spectroscopy.

  8. Crystal structure of 4-[(Benzylidene-amino)]-2-(2-oxo-2-phenylethyl)-5-thiophen-2-ylmethyl-2,4-dihydro-[1,2,4]triazol-3-one

    NASA Astrophysics Data System (ADS)

    Tanak, H.; Işik, Ş.

    2014-12-01

    The molecular structure of the title compound C22H18N4O2S was characterized by single crystal X-ray diffraction method. The compound crystallizes in the orthorhombic space group Pbca with a = 10.1970 (4) Å, b = 26.8880 (5) Å, c = 15.2119 (13) Å, Z = 8, V = 4170.8 (4) Å3. In the title compound, benzyl rings and thiophene ring are bridged by 1,2,4-triazole ring system. The thiophene ring is disordered over two positions, which are approximately parallel and oppositely orientated. The major component refined to a siteoccupancy factor of 0.731 (3). An intramolecular C-H⋯O hydrogen bond generates an S(6) ring motif. In the crystal, a C-H⋯O hydrogen bond links the molecules into a C(6) chain along the c axis. A weak C-H⋯π interaction also occurs.

  9. Selective Crystallization Behavior of CaO-SiO2-Al2O3-MgO-FetO-P2O5 Steelmaking Slags Modified through P2O5 and Al2O3

    NASA Astrophysics Data System (ADS)

    Wang, Zhanjun; Sun, Yongqi; Sridhar, Seetharaman; Zhang, Mei; Guo, Min; Zhang, Zuotai

    2015-10-01

    In this study, the selective crystallization behavior of synthetic FetO-rich steelmaking slags modified by P2O5 and Al2O3 additions was explored using non-isothermal differential scanning calorimetry, X-ray diffraction, and field emission scanning electron microscopy techniques. Continuous cooling transformation diagrams of Fe-enriched and P-enriched phases were constructed. It was found that P2O5 addition can suppress the crystallization due to the increasing viscosity caused by increasing degree of polymerization; however, an increase of Al2O3 content accelerated the precipitation of dystectic MgFeAlO4, copolymerized by [AlO4]-tetrahedra and [FeO4]-tetrahedra units. It was also noted that the content of phosphorus in P-enriched phase can reach a high value as 28.71 wt pct for the slags modified by 15.17 wt pct Al2O3. The non-isothermal crystallization kinetics derived from activation energy and the structure of the slags explained by Raman spectra were further analyzed, which was well in accordance with the above analysis.

  10. A phosphomide based PNP ligand, 2,6-{Ph2PC(O)}2(C5H3N), showing PP, PNP and PNO coordination modes.

    PubMed

    Kumar, Pawan; Kashid, Vitthalrao S; Reddi, Yernaidu; Mague, Joel T; Sunoj, Raghavan B; Balakrishna, Maravanji S

    2015-03-01

    A new class of PNP pincer ligands, pyridine-2,6-diylbis(diphenylphosphino)methanone, 2,6-{Ph2PC(O)}2(C5H3N) (1) (hereafter referred to as "bis(phosphomide)"), was prepared by the reaction of picolinoyldichloride with diphenylphosphine in the presence of triethylamine. The bis(phosphomide) 1 shows symmetrical PNP, unsymmetrical PNO and simple bidentate PP coordination modes when treated with various transition metal precursors. The reaction between 1 and [Ru(p-cymene)Cl2]2 in a 1 : 1 molar ratio yielded a binuclear complex [Ru2Cl4(NCCH3)(p-cymene){2,6-{Ph2PC(O)}2(C5H3N)}] (2) containing an unsymmetrical PNO pincer cage around one of the ruthenium centers, whereas the second ruthenium is bonded to the other phosphorus atom along with cymene and two chloride atoms. Symmetrical pincer complexes [RuCl(NCCH3)2{2,6-{Ph2PC(O)}2(C5H3N)}](ClO4) (3), [Ru(η(5)-C5H5){2,6-{Ph2PC(O)}2(C5H3N)}](OTf) (4) and [RhCl{2,6-{Ph2PC(O)}2(C5H3N)}] (5) were obtained in the respective reactions of 1 with [RuCl(NCCH3)2(p-cymene)](ClO4), [Ru(η(5)-C5H5)Cl(PPh3)2] and [Rh(COD)Cl]2. Group 10 metal complexes [NiCl{2,6-{Ph2PC(O)}2(C5H3N)}](BF4) (6), [PdCl{2,6-{Ph2PC(O)}2(C5H3N)}]ClO4 (7) and [PtCl{2,6-{Ph2PC(O)}2(C5H3N)}]ClO4 (8) were obtained by transmetallation reactions of in situ generated Ag(I) salts of 1 with Ni(DME)Cl2 or M(COD)Cl2 (M = Ni, Pd and Pt). The reactions between 1 and CuX or [Cu(NCCH3)4](BF4) produced mononuclear complexes of the type [CuX{2,6-{Ph2PC(O)}2(C5H3N)}] (9, X = Cl; 10, X = Br; 11, X = I), [Cu(NCCH3){Ph2C(O)}2(C5H3N)}](BF4) (12) and [Cu{Ph2C(O)}2(C5H3N)}2](BF4) (13). Similarly, the silver complexes [AgX{2,6-{Ph2PC(O)}2(C5H3N)}] (14, X = ClO4; 15, X = Br) were obtained by the treatment of 1 with AgClO4 or AgBr in 1 : 1 molar ratios. Treatment of 1 with AuCl(SMe2) in 1 : 1 and 1 : 2 molar ratios produced mono- and binuclear complexes, [AuCl{2,6-{Ph2PC(O)}2(C5H3N)}] (16) and [Au2Cl2{2,6-{Ph2PC(O)}2(C5H3N)}] (17), in good yield. The structures of ligand 1

  11. Synthesis and preliminary evaluation of 5,7-dimethyl-2-aryl-3H-pyrrolizin-3-ones as angiogenesis inhibitors.

    PubMed

    Kirk, Nicholas S; Bezos, Anna; Willis, Anthony C; Sudta, Pichit; Suksamrarn, Sunit; Parish, Christopher R; Ranson, Marie; Kelso, Michael J

    2016-04-01

    Sunitinib (Sutent®) is a receptor tyrosine kinase (RTK) and angiogenesis inhibitor approved for the treatment of renal cell carcinomas, gastrointestinal stromal tumours and pancreatic neuroendocrine tumours. A key structural motif retained throughout medicinal chemistry efforts during sunitinib's development was the indoline-2-one group. In the search for new anti-angiogenic scaffolds, we previously reported that non-indoline-2-one-based derivatives of semaxanib (SU5416, a structurally simpler sunitinib predecessor that underwent Phase III trials) are active as angiogenesis inhibitors, indicating that the group is not essential for activity. This Letter describes the synthesis and structure-activity relationships of another class of non-indoline-2-one angiogenesis inhibitors related to sunitinib/semaxanib; the 5,7-dimethyl-2-aryl-3H-pyrrolizin-3-ones. A focussed library of 19 analogues was prepared using a simple novel process, wherein commercially available substituted arylacetic acids activated with an amide coupling reagent (HBTU) were reacted with the potassium salt of 3,5-dimethyl-1H-pyrrole-2-carbaldehyde in one-pot. Screening of the library using a cell-based endothelial tube formation assay identified 6 compounds with anti-angiogenesis activity. Two of the compounds were advanced to the more physiologically relevant rat aortic ring assay, where they showed similar inhibitory effects to semaxanib at 10μg/mL, confirming that 5,7-dimethyl-2-aryl-3H-pyrrolizin-3-ones represent a new class of angiogenesis inhibitors. PMID:26912111

  12. Sensitivity of 2,6-Diamino-3, 5-Dinitropyrazine-1-Oxide

    SciTech Connect

    Tarver, C M; Urtiew, P A; Tran, T D

    2005-01-20

    The thermal and shock sensitivities of plastic bonded explosive formations based on 2,6-diamino-3,5-dinitropyrazine-1-oxide (commonly called LLM-105 for Lawrence Livermore Molecule No.105) are reported. The One Dimensional Time to Explosion (ODTX) apparatus was used to generate times to thermal explosion at various initial temperatures. A four-reaction chemical decomposition model was developed to calculate the time to thermal explosion versus inverse temperature curve. Three embedded manganin pressure gauge experiments were fired at different initial pressures to measure the pressure buildup and the distance required for transition to detonation. An Ignition and Growth reactive model was calibrated to this shock initiation data. LLM-105 exhibited thermal and shock sensitivities intermediate between those of triaminotrinitrobenzene (TATB) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine (HMX).

  13. New monoclonal antibodies specific for 1-(5-fluoropentyl)-3-(2-iodobenzoyl)indole.

    PubMed

    Nakayama, Hiroshi; Kenjyou, Noriko

    2015-02-01

    1-(5-fluoropentyl)-3-(2-iodobenzoyl)indole (AM694) is one of the synthetic cannabinoids and an illegal drug in Japan. It is important to generate a monoclonal antibody (MAb) against AM694 for use in the rapid and sensitive detection of the drug. Two monoclonal antibodies, named HN0124 (IgG1) and NK0504 (IgG1), were obtained, which were possibly effective for detecting AM694 and its derivatives. The cross-reactive ability of these MAbs was evaluated using a competitive enzyme-linked immunosorbent assay. In the results, both of these antibodies recognize 1-(5-fluoropentyl)-3-(2-iodobenzoyl)indole, 1-(5-fluoropentyl)-3-(3-iodobenzoyl)indole, 1-(5-fluoropentyl)-3-(4-iodobenzoyl)indole. Forty nmol/L AM694 can be detected using HN0124 MAb. Thus, MAbs produced in this study could be considered a useful tool for the detection of AM694. PMID:25723285

  14. (E)-2,2-Dimethyl-5-(3-phenyl-allyl-idene)-1,3-dioxane-4,6-dione.

    PubMed

    Zeng, Wu-Lan

    2010-01-01

    The title compound, C(15)H(14)O(4), was prepared by the reaction of 2,2-dimethyl-1,3-dioxane-4,6-dione and (Z)-3-phenyl-acryl-aldehyde in ethanol. The dioxane ring is in a sofa conformation with the C atom bonded to the two methyl groups forming the flap. With the exception of the flap atom and the methyl group C atoms, all other non-H atoms are essentially planar, with an r.m.s. deviation of 0.067 (1) Å. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds. PMID:21589113

  15. Alum Catalyzed Simple, Efficient, and Green Synthesis of 2-[3-Amino-5-methyl-5-(pyridin-3-yl)-1,5-dihydro-4H-1,2,4-triazol-4-yl]propanoic Acid Derivatives in Aqueous Media

    PubMed Central

    Sachdeva, Harshita; Dwivedi, Diksha; Saroj, Rekha

    2013-01-01

    Alum (KAl(SO4)2·12H2O) is an inexpensive, efficient, and nontoxic catalyst used for the synthesis of 2-[3-amino-5-methyl-5-(pyridin-3-yl)-1,5-dihydro-4H-1,2,4-triazol-4-yl]propanoic acid derivatives in aqueous media by the reaction of 3-acetyl pyridine (1), amino acids (2)/(6), and thiosemicarbazide (4) at 80°C. This methodology offers significant improvements for the synthesis of products with regards to the yield of products, simplicity in operation, and green aspects by avoiding toxic catalysts which uphold the motto of green chemistry. Synthesized compounds have been characterized by FT-IR, 13C NMR, and 1HNMR spectroscopy. PMID:24288503

  16. New 3'-O-aromatic acyl-5-fluoro-2'-deoxyuridine derivatives as potential anticancer agents.

    PubMed

    Szymańska-Michalak, Agnieszka; Wawrzyniak, Dariusz; Framski, Grzegorz; Kujda, Marta; Zgoła, Paulina; Stawinski, Jacek; Barciszewski, Jan; Boryski, Jerzy; Kraszewski, Adam

    2016-06-10

    New aromatic and aliphatic 3'-O-acyl-5-fluoro-2'-deoxyuridine derivatives were synthesized and evaluated as candidates for prodrugs against various cancer cell lines. As the most promising candidate for antimalignant therapeutics was found a dual-acting acyl derivative 7h, which apparently released not only the known anticancer nucleoside, 5-fluoro-2'-deoxyuridine (FdU), but also an additional active metabolite, acetylsalicylic acid, reinforcing thus therapeutic effect of FdU. Promising therapeutic indices showed also some aromatic dicarboxylic acids derivatives decorated with FdU esters (11 and 12). PMID:26994842

  17. Zonal Wave Number 2 Rossby Wave (3.5-day oscillation) Over The Martian Lower Atmosphere

    NASA Astrophysics Data System (ADS)

    Ghosh, P.; Thokuluwa, R. K.

    2013-12-01

    Over the Mars, height (800-50 Pascal pressure coordinate) profiles of temperature (K), measured by radio occultation technique during the MGS (Mars Global Surveyor) mission, obtained for the period of 1-10 January 2006 at the Martian latitude of ~63N in almost all the longitudes are analyzed to study the characteristics of the 3.5-day oscillation. To avoid significant data gaps in a particular longitude sector, we selected a set of 7 Mars longitude regions with ranges of 0-30E, 35-60E, 65-95E, 190-230E, 250-280E, 290-320E, and 325-360E to study the global characteristics of the 3.5-day oscillation. The 3.5-day oscillation is not selected as a-priori but observed as a most significant oscillation during this period of 1-10 January 2006. It is observed that in the longitude of 0-30E, the 3.5-day oscillation shows statistically significant power (above the 95% confidence level white noise) from the lowest height (800 Pascal, 8 hPa) itself and up to the height of 450 Pascal level with the maximum power of ~130 K^2 at the 600 & 650 Pascal levels. It started to grow from the power of ~ 50 K^2 at the lowest height of 800 Pascal level and reached the maximum power in the height of 600-650 Pascal level and then it started to get lessened monotonously up to the height of 450 Pascal level where its power is ~ 20 K^2. Beyond this height and up to the height of 50 Pascal level, the wave amplitude is below the white noise level. As the phase of the wave is almost constant at all the height levels, it seems that the observed 3.5-day oscillation is a stationary wave with respect to the height. In the 35-60 E longitude sector, the vertical structure of the 3.5-day oscillation is similar to what observed for the 0-30 E longitude region but the power is statistically insignificant at all the heights. However in the 65-95E longitude sector, the wave grows from the lowest level (70 K^2) of 800 Pascal to its maximum power of 280 K^2 in the height of 700 Pascal level and then it started

  18. Isothermal sections of the quasi-ternary systems Ag2S(Se)-Ga2S(Se)3-In2S(Se)3 at 820 K and the physical properties of the ternary phases Ga5.5In4.5S15, Ga6In4Se15 and Ga5.5In4.5S15:Er3+, Ga6In4Se15:Er3+

    NASA Astrophysics Data System (ADS)

    Ivashchenko, I. A.; Danyliuk, I. V.; Gulay, L. D.; Halyan, V. V.; Olekseyuk, I. D.

    2016-05-01

    Isothermal sections of the quasi-ternary systems Ag2S(Se)-Ga2S(Se)3-In2S(Se)3 at 820 K were compared. Along the 50 mol% Ag2S(Se), both systems feature continuous solid solutions with the chalcopyrite structure. Along the 17 mol% Ag2S(Se), the interactions at the AgIn5S(Se)8-"AgGa5S(Se)8" sections are different. In the Ag2S-Ga2S3-In2S3 system the existence of the layered phase AgGaxIn5-xS8, 2.25≤x≤2.85, was confirmed (S.G. P63mc). The Ag2Se-Ga2Se3-In2Se3 system features the formation of solid solution (up to 53 mol% Ga2Se3) based on AgIn5Se8 (S.G. P-42m). Crystal structure, atomic coordinates were determined by powder diffraction method for samples from the homogeneity region of AgIn5Se8. Specific conductivities of the crystals Ga6In4Se15 (1.33·10-6 Ω-1 m-1), Ga5.94In3.96Er0.1Se15 (3.17·10-6 Ω-1 m-1), Ga5.5In4.5S15 (7.94·10-6 Ω-1 m-1), Ga5.46In4.47Er0.07S15 (1·10-9 Ω-1 m-1) were measured at room temperature. Optical absorption and photoconductivity spectra were recorded in the range 400-760 nm. The introduction of erbium leads to an increase in the absorption coefficient and to the appearance of absorption bands at 530, 660, 810, 980, 1530 nm.

  19. Differentiation of 5-hydroxytryptamine2 receptor subtypes using sup 125 I-R-(-)2,5-dimethoxy-4-iodo-phenylisopropylamine and sup 3 H-ketanserin

    SciTech Connect

    McKenna, D.J.; Peroutka, S.J. )

    1989-10-01

    The radioligand binding characteristics of 125I-R-(-)4-iodo-2,5-dimethoxyphenylisopropylamine (125I-R-(-)DOI) and 3H-ketanserin were compared in rat and bovine cortical membranes. In rat cortex, 125I-R-(-)DOI labels a relatively low density of binding sites (Bmax = 2.5 +/- 0.2 pmol/gm tissue) with high affinity (KD = 0.63 +/- 0.09 nM). In bovine cortex, specific binding of 125I-R-(-)DOI represents less than 20% of total binding at radioligand concentrations above 0.6 nM, and, therefore, the data cannot be analyzed adequately by Scatchard transformation. By contrast, 3H-ketanserin displays saturable, specific high-affinity binding in both rat cortex (KD = 1.0 +/- 0.1 nM; Bmax = 11 +/- 0.4 pmol/gm tissue) and bovine cortex (KD = 1.2 +/- 0.2 nM; Bmax = 5.3 +/- 0.4 pmol/gm tissue). Ki values for 30 drugs were determined for 125I-R-(-)DOI-labeled sites in rat cortex and 3H-ketanserin-labeled sites in bovine cortex. 5-Hydroxytryptamine (5-HT) displays 250-fold higher selectivity for the 125I-R-(-)DOI-labeled sites (Ki = 3.0 +/- 0.7 nM) than for the 3H-ketanserin-labeled sites (Ki = 750 +/- 50 nM). Structural congeners of R-(-)DOI display 80- to 160-fold higher affinity for the 125I-R-(-)DOI binding site than for the 3H-ketanserin-labeled binding site. d-LSD and putative 5-HT2 antagonists are approximately equipotent at both sites. Significant correlations were found between drug affinities for 125I-R-(-)DOI-labeled sites in rat cortex and putative 5-HT2A sites labeled previously by 77Br-R-(-)DOB (r = 0.93, p less than 0.01), putative 5-HT2B sites labeled by 3H-ketanserin in bovine cortex (r = 0.63, p less than 0.01), and 5-HT1C binding sites that have been characterized by other investigators (r = 0.78, p less than 0.01). No significant correlations were found between drug affinities for 125I-R-(-)DOI-labeled sites in rat cortex and 5-HT1A, 5-HT1B, 5-HT1D, or 5-HT3 sites, as determined by previous investigators.

  20. A HPLC method for the quantitative determination of N-(2-hydroxy-5-nitrophenylcarbamothioyl)-3,5-dimethylbenzamide in biological samples.

    PubMed

    Skidan, Igor; Grunwald, Jacob; Thekkedath, Ritesh; Degterev, Alexei; Torchilin, Vladimir

    2011-06-01

    A sensitive and simple HPLC method was developed for the determination of a novel compound, a potential anti-cancer drug, N-(2-hydroxy-5-nitrophenylcarbamothioyl)-3,5-dimethylbenzamide (DM-PIT-1), a member of the new structural class of non-phosphoinositide small molecule antagonist of phosphatidylinositol-3,4,5-trisphosphate-pleckstrin-homology domain interactions, in mouse plasma and tumor tissue homogenates. The chromatographic separation of DM-PIT-1 was achieved on C18 column using isocratic elution with acetonitrile-water (70:30) containing 0.1% formic acid (v/v). DM-PIT-1 was detected by UV absorbance at 320 nm and confirmed by LC-MS. The extraction of the DM-PIT-1 from the plasma and tumor tissue with methylene chloride resulted in its high recovery (70-80%). HPLC calibration curves for DM-PIT-1 based on the extracts from the mouse plasma and tumor tissue samples were linear over a broad concentration range of 0.25-20 μg/ml/g, with intra/inter-day accuracy of 95% and the precision of variation below 10%. The limits of detection and quantification were 0.1 ng and 0.2 ng, respectively. The described method was successfully applied to study the pharmacokinetics of the DM-PIT-1 following the parenteral injections of DM-PIT-1 entrapped in 1,2-disteratoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene-glycol)-2000] (PEG-PE) micelles. PMID:21514904

  1. Synthesis and anti-inflammatory activity of 5-(6-methyl-2-substituted 4-pyrimidinyloxymethyl)-1,3,4-oxadiazole-2-thiones and their 3-morpholinomethyl derivatives.

    PubMed

    Jakubkiene, Virginija; Burbuliene, Milda Malvina; Mekuskiene, Giedrute; Udrenaite, Emilija; Gaidelis, Povilas; Vainilavicius, Povilas

    2003-04-01

    The synthesis of 5-(6-methyl-2-substituted 4-pyrimidinyloxymethyl)-2,3-dihydro-1,3,4-oxadiazole-2-thiones and their 3-morpholinomethyl derivatives and the results of anti-inflammatory activity in vivo are described. Most of the tested compounds exhibited anti-inflammatory activity and some of them were more active than acetylsalicylic acid. PMID:12727542

  2. Observation of the 5 p3 /2→6 p3 /2 electric-dipole-forbidden transition in atomic rubidium using optical-optical double-resonance spectroscopy

    NASA Astrophysics Data System (ADS)

    Ponciano-Ojeda, F.; Hernández-Gómez, S.; López-Hernández, O.; Mojica-Casique, C.; Colín-Rodríguez, R.; Ramírez-Martínez, F.; Flores-Mijangos, J.; Sahagún, D.; Jáuregui, R.; Jiménez-Mier, J.

    2015-10-01

    Direct evidence of excitation of the 5 p3 /2→6 p3 /2 electric-dipole-forbidden transition in atomic rubidium is presented. The experiments were performed in a room-temperature rubidium cell with continuous-wave external cavity diode lasers. Optical-optical double-resonance spectroscopy with counterpropagating beams allows the detection of the nondipole transition free of Doppler broadening. The 5 p3 /2 state is prepared by excitation with a laser locked to the maximum F cyclic transition of the D2 line, and the forbidden transition is produced by excitation with a 911 nm laser. Production of the forbidden transition is monitored by detection of the 420 nm fluorescence that results from decay of the 6 p3 /2 state. Spectra with three narrow lines (≈13 MHz FWHM) with the characteristic F -1 , F , and F +1 splitting of the 6 p3 /2 hyperfine structure in both rubidium isotopes were obtained. The results are in very good agreement with a direct calculation that takes into account the 5 s →5 p3 /2 preparation dynamics, the 5 p3 /2→6 p3 /2 nondipole excitation geometry, and the 6 p3 /25 s1 /2 decay. The comparison also shows that the electric-dipole-forbidden transition is a very sensitive probe of the preparation dynamics.

  3. Unprecedented solid-state chemical reaction—from (C3N2H5)3SbBr6·H2O to (C3N2H5)5Sb2Br11. From centrosymmetric to non-centrosymmetric crystal structure

    NASA Astrophysics Data System (ADS)

    Piecha, A.; Gągor, A.; Pietraszko, A.; Jakubas, R.

    2010-12-01

    Tris(imidazolium) hexabromoantimonate(III) hydrate, (C3N2H5)3SbBr6·H2O, (abbreviated as TIBA) has been synthesized and characterized by X-ray (at 295, 225, 160, and 110 K), differential scanning calorimetry, dilatometry, and dielectric spectroscopy. At room temperature (phase I), the structure consists of discrete SbB 6- anions, disordered imidazolium cations, and water molecules forming a 3D array of hydrogen bonds. Below room temperature, TIBA was found to undergo isostructural discontinuous phase transition at 212/221 K (cooling-heating) (P21/c↔P21/c). The phase transition mechanism is characterized by two contributions: an order-disorder (cationic substructure) and a displacive (water molecules) one. At high temperatures, the TIBA crystal was found to undergo an unprecedented in situ solid-state chemical reaction: 2(C3N2H5)3SbBr6·H2O→(C3N2H5)5Sb2Br+(C3N2H5)Br+2H2O This chemical transformation leads to multiphase crystallites dominated by an amorphous phase of (C3N2H5)5Sb2Br11. The creation of ferroelectric crystallites - (C3N2H5)5Sb2Br11 - in an "annealed" sample of (C3N2H5)3SbBr6·H2O was confirmed by X-ray diffraction phase analysis, dielectric spectroscopy, and pyroelectric measurements. The dielectric response of the electric permittivity and the critical slowing down of the process observed near 140 K in the "annealed" sample of TIBA are treated as a "fingerprint" of a neat (C3N2H5)5Sb2Br11 ferroelectric.

  4. Mo 2O 5(OCH 3) 2and Mo 2O 5(OCH 3) 2·2CH 3OH: New Structural Insights Derived from Reaction Chemistry and Diffraction Techniques

    NASA Astrophysics Data System (ADS)

    McCarron, E. M.; Harlow, R. L.; Li, Z. G.; Suto, C.; Yuen, Y.

    1998-03-01

    The reaction of molybdenum trioxide dihydrate, MoO 3· 2H 2O, with methanol produces the title compounds. That these molybdenum oxy-methoxides decompose with liberation of CH 2O suggests that they represent exquisite models for selective oxidation of methanol to formaldehyde over molybdate catalysts. Although a number of physical techniques have been employed to elucidate certain structural features, the actual structures remain unknown. However, their unit cells have been determined for the first time by employing the complimentary nature of electron and powder diffraction techniques. This information coupled with structural insights derived from careful studies of the reaction chemistry, in particular, the synthesis and characterization of a new amorphous intermediate, MoO 3·CH 3OH, has allowed fairly detailed structures for these interesting molybdenum oxy-methoxide materials to be proposed.

  5. 2,5-dimethylthiophene coordination to three metal centers in (. eta. sup 4 ,S-. mu. sub 3 -2,5-Me sub 2 T)(IrCp sup * )(Mo(CO) sub 2 Cp) sub 2

    SciTech Connect

    Chen, Jiabi; Angelici, R.J. )

    1990-03-01

    The reaction of Cp{sup *}Ir({eta}{sup 4}-2,5-Me{sub 2}T), where {eta}{sup 4}-2,5-Me{sub 2}T is 2,5-dimethylthiophene coordinated through the four ring carbons, with Cp(CO){sub 2}Mo{triple bond}Mo(CO){sub 2}Cp gives ({eta}{sup 4},S-{mu}{sub 3}-2,5-Me{sub 2}T)(IrCp{sup *})(Mo(CO){sub 2}Cp){sub 2}, in which the bridging thiophene is {eta}{sup 4}-coordinated to the Ir and bonded via the sulfur to both Mo atoms. The same product is obtained from the ring-opened isomer of Cp{sup *}Ir(2,5-Me{sub 2}T). The structure of the product, which is the first example of a thiophene coordinated to three metal centers, was established by X-ray crystallography.

  6. Fluoroaluminates of purine and DNA bases, adenine, guanine: [H pur] 2·(AlF 5), [H ade] 3·(AlF 6)·6.5H 2O, [H guan] 3·(Al 3F 12)

    NASA Astrophysics Data System (ADS)

    Cadiau, A.; Adil, K.; Hemon-Ribaud, A.; Leblanc, M.; Jouanneaux, A.; Slawin, A. M. Z.; Lightfoot, P.; Maisonneuve, V.

    2011-01-01

    New purinium, adeninium and guaninium fluoroaluminates, [H pur] 2·(AlF 5), [H ade] 3·(AlF 6)·6.5H 2O and [H guan] 3·(Al 3F 12), are synthesized by microwave heating assisted hydrothermal synthesis at 120 °C or 190 °C. The crystallisation is difficult; all crystals of [H pur] 2·(AlF 5) and [H ade] 3·(AlF 6)·6.5H 2O are very small while only a microcrystalline powder of [H guan] 3·(Al 3F 12) is obtained. The structures are determined from crystal ([H pur] 2·(AlF 5) and [H ade] 3·(AlF 6)·6.5H 2O) or powder ([H guan] 3·(Al 3F 12)) X-ray diffraction data. In [H pur] 2·(AlF 5), trans-chains of corner sharing octahedra lie along the c axis of the tetragonal cell ( a = 18.997(2) Å, c = 3.6980(4) Å, P4/ n, Z = 4). In [H ade] 3·(AlF 6)·6.5H 2O, the octahedral AlF 6 units lie in (010) planes with water molecules. In [H guan] 3·(Al 3F 12), trimers of corner sharing octahedra are associated by opposite vertices along the c axis of the trigonal cell ( a = 14.254(1) Å, c = 3.629(1) Å, P3, Z = 1). The purine, adenine and guanine amines are monoprotonated and lie between the preceding chains or layers. Hydrogen bonds between fluoride ions and amine groups of organic cations or, eventually, water molecules ensure the stability of the structures, together with N-H⋯O intermolecular bonds between guaninium cations in [H guan] 3·(Al 3F 12). The N(7)H-amino and N(9)H-amino tautomeric forms of [H ade] + are simultaneously found in [H ade] 3·(AlF 6)·6.5H 2O.

  7. Thermodynamics of lanthanide and uranyl complexes with tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THFTCA).

    SciTech Connect

    Morss, L. R.; Nash, K. L.; Tennessee Technological Univ.

    2000-01-01

    We present the results of an investigation of the thermochemistry of the complexation of La{sup 3+} Nd{sup 3+}, Eu{sup 3+}, Dy{sup 3+}, Tm{sup 3+}, and UO{sub 2}{sup 2+} by tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THFTCA). This predisposed structural analog to oxydiacetic acid (ODA) has been previously shown both to exhibit greater sensitivity to lanthanide cation radius than complexes with the unconstrained ODA and to form anomalously weak complexes with UO{sub 2}{sup 2+}. Our purpose is to interpret these observations in terms of the balance between enthalpy and entropy contributions to the overall complexation thermodynamics. Enthalpies have been calculated from titration calorimetry experiments both for the protonation of the free ligand and for the formation of selected 1:1 and 1:2 complexes in pH 2-3 acidic media (I = 0.1 M). The complexation entropies for the lanthanide complexes have been calculated using the previously reported stability constants for the MH{sub 2}L{sup +}, MHL, and M(H{sub 2}L){sup 2-}. The stability constants for the uranyl complexes have been determined by potentiometric titration and these values used to calculate the thermodynamic parameters. Complexation enthalpies for the 1:1 lanthanide-THFTCA complexes (MH{sub 2}L{sup +} species) are nearly identical to those of the lanthanide ODA complexes. Therefore, the size-selectivity observed in the lanthanide-THFTCA complexes arises from the complexation entropy. The comparative weakness of the uranyl complexes with THFTCA also is accounted for thermodynamically in the entropy term. Calculations based on an electrostatic model for complexation entropy and molecular mechanics modeling are used to help interpret the experimental results.

  8. Optical Properties and Junction Characteristics of 6-(5-Bromothiohen-2-yl)-2,3-Dihydro-1-Methyl-3-Oxo-2-Phenyl-1H-Pyrazolo[4,3-b]Pyridine-5-Carbonitrile Films

    NASA Astrophysics Data System (ADS)

    Zedan, I. T.; El-Taweel, F. M. A.; Abu El-Enein, R. A. N.; Nawar, H. H.; El-Menyawy, E. M.

    2016-08-01

    In this study, 6-(5-bromothiohen-2-yl)-2,3-dihydro-1-methyl-3-oxo-2-phenyl-1H-pyrazolo[4,3-b]pyridine-5-carbonitrile (BDPC) powder was synthesized. BDPC powder showed a polycrystalline structure, whereas the thermally evaporated films had an amorphous structure. The optical parameters such as absorption coefficient and refractive index were calculated in the spectral range 200-500 nm. Spectral distribution analysis of the absorption coefficient revealed that the films had an indirect band transitions with energy gaps of 2.57 eV and 3.5 eV. According to the single oscillator model, the oscillation energy, dispersion energy, and dielectric constant were estimated. The room-temperature current-voltage characteristics of the fabricated Au/BDPC/p-Si/Al heterojunction showed diode-like behavior. The ideality factor, the barrier height and series resistance were determined based on thermionic emission theory and Norde's function. At reverse bias, the current was interpreted in terms of the Schottky and pool-Frenkle effects in low and high voltages, respectively. The built-in voltage, carrier concentration and barrier height were obtained using capacitance-voltage characteristics.

  9. Synthesis and structural studies of Sr 2Co 2- xAl xO 5, 0.3⩽ x⩽0.5

    NASA Astrophysics Data System (ADS)

    Lindberg, F.; Svensson, G.; Istomin, S. Ya.; Aleshinskaya, S. V.; Antipov, E. V.

    2004-04-01

    Sr 2Co 2- xAl xO 5, 0.3⩽ x⩽0.5, with a perovskite related structure has been synthesized. The XRD powder patterns showed reflections from the basic cubic perovskite structure along with some additional weak superstructure reflections. Electron diffraction (ED) and high-resolution transmission electron microscopy (HRTEM) studies show that crystallites of Sr 2Co 2- xAl xO 5 consist of small intergrown differently oriented domains, about 40 Å in diameter, with brownmillerite structure.

  10. Interstellar dust spectra between 2.5 and 3.3 microns - A search for hydrated silicates

    NASA Technical Reports Server (NTRS)

    Knacke, R. F.; Mccorkle, S.; Puetter, R. C.; Erickson, E.

    1985-01-01

    Spectra in the 2.5-3.3 micron wavelength region of VI Cyg 12, AFGL 2205, and AFGL 2885 were obtained in a search for bound water, hydroxyl groups, and hydrated minerals in interstellar dust. No new absorption bands were found. Comparison of expected strengths of bands of serpentine and chlorite-like minerals with the data suggests that less than 25 percent and 50 percent, respectively, of the silicate in the grains is composed of these materials.

  11. The crystal structure of 4'-{4-[(2,2,5,5-tetra-methyl-N-oxyl-3-pyrrolin-3-yl)ethyn-yl]phen-yl}-2,2':6',2''-terpyridine.

    PubMed

    Meyer, Andreas; Wiecek, Jennifer; Schnakenburg, Gregor; Schiemann, Olav

    2015-07-01

    The terpyridine group of the title compound, C31H27N4O, assumes an all-transoid conformation and is essentially planar with the dihedral angles between the mean planes of the central pyridine and the two outer rings amounting to 3.87 (5) and 1.98 (5)°. The pyrroline-N-oxyl group commonly seen in such nitroxyls is found in the title structure and the mean plane of the pyrroline ring subtends a dihedral angle of 88.44 (7)° to the mean plane of the central pyridine ring. The intra-molecular separation between the nitrogen atom of the central pyridine unit of the terpyridine group and the nitroxyl group is 14.120 (2) Å. In the crystal, the mol-ecules are arranged in layers stacked along [001]. Slipped face-to-face π-π inter-actions between the pyridine rings are observed along this direction with the shortest centroid-centroid distances amounting to 3.700 (1) and 3.781 (1) Å. Furthermore, edge-on C-H⋯π inter-actions between the phenyl-ene rings of neighbouring mol-ecules are observed along this direction. A two-dimensional C-H⋯O hydrogen-bonded network is formed within the (010) plane. The shortest O⋯O separation between neighbouring mol-ecules is 5.412 (3) Å. PMID:26279889

  12. Synthesis, crystal structure and DFT studies of N-(4-acetyl-5,5-dimethyl-4,5-dihydro-1,3,4-thiadiazol-2-yl)acetamide

    SciTech Connect

    Gautam, P.; Gautam, D.; Chaudhary, R. P.

    2013-12-15

    The title compound N-(4-acetyl-5,5-dimethyl-4,5-dihydro-1,3,4-thiadiazol-2-yl)acetamide (III) was obtained from the reaction of 2-(propan-2-ylidene)hydrazinecarbothioamide (II) with acetic anhydride instead of formation of the desired thiosemcarbazide derivative of Meldrum acid. The structures of II and III were established by elemental analysis, IR, NMR, Mass and X-ray crystallographic studies. II crystallizes in triclinic system, sp. gr. P-bar1 Z = 2; III crystallizes in the monoclinic system, sp. gr. P2{sub 1}/c, Z = 8. Density functional theory (DFT) calculations have been carried out for III. {sup 1}H and {sup 13}C NMR of III has been calculated and correlated with experimental results.

  13. Benzene-1,3,5-tri-carb-oxy-lic acid-pyridinium-2-olate (1/3).

    PubMed

    Campos-Gaxiola, José J; Zamora Falcon, Felipe; Corral Higuera, Ramón; Höpfl, Herbert; Cruz-Enríquez, Adriana

    2014-04-01

    The asymmetric unit of the title compound, C9H6O6·3C5H5NO, contains one benzene-1,3,5-tri-carb-oxy-lic acid mol-ecule (BTA) and three pyridin-2-ol mol-ecules each present in the zwitterion form. In the crystal, these entities are linked through O-H⋯O(-) and N(+)-H⋯O(-) hydrogen bonds, forming sheets parallel to (10-1). These layers contain macrocyclic rings of composition [BTA]2[pyol]6 and with graph-set notation R (6) 8(44), which are stacked along c through π-π inter-actions [inter-centroid distances = 3.536 (2)-3.948 (3) Å]. They are inter-connected by N(+)-H⋯O(-) hydrogen-bonded chains of pyridin-2-ol mol-ecules running parallel to c, forming a three-dimensional network. There are also C-H⋯O hydrogen bonds present which reinforce the three-dimensional structure. PMID:24826154

  14. Highly selective aldose reductase inhibitors. 3. Structural diversity of 3-(arylmethyl)-2,4,5-trioxoimidazolidine-1-acetic acids.

    PubMed

    Kotani, T; Nagaki, Y; Ishii, A; Konishi, Y; Yago, H; Suehiro, S; Okukado, N; Okamoto, K

    1997-02-28

    Accumulation of intracellular sorbitol, the reduced product of glucose, catalyzed by aldose reductase (AR) (EC 1.1.1.21), is thought to be the cause of the development of diabetic complications. Our attention is focused on finding compounds which inhibit AR without significantly inhibiting aldehyde reductase (ALR) (EC 1.1.1.2). The uracil or 2,4-dioxoimidazolidine skeleton having the benzothiazolyl or 4-chloro-3-nitrophenyl group as an aryl part indicated not only extremely high AR inhibitory activity but also AR selectivity. The ratio of IC50(ALR)/IC50(AR) of 3-[(5-chlorobenzothiazol-2-yl)methyl]-1,2,3,4-tetrahydro-2,4- dioxopyrimidine-1-acetic acid (47d) was more than 17 500. The uracil skeleton with the benzothiazolyl moiety seemed to be the best combination for selective AR inhibition. PMID:9057855

  15. Gas-phase reactions of nopinone, 3-isopropenyl-6-oxo-heptanal, and 5-methyl-5-vinyltetrahydrofuran-2-ol with OH, NO{sub 3}, and ozone

    SciTech Connect

    Calogirou, A.; Jensen, N.R.; Nielsen, C.J.; Kotzias, D.; Hjorth, J.

    1999-02-01

    In the troposphere, {alpha}-pinene, {beta}-pinene, limonene, and linalool are mainly oxidized to pinonaldehyde, nopinone, 3-isopropenyl-6-oxoheptanal (IPOH), and 5-methyl-5-vinyltetrahydrofuran-2-ol (MVT), respectively. The rate constant of the reactions of nopinone, IPOH, and MVT with OH, NO{sub 3}, and O{sub 3} were determined by long path FT-IR spectroscopy, and the oxidation products from the reactions between the OH radical and pinonaldehyde, nopinone, IPOH, and MVT were investigated using GC-MS and HPLC. The reaction rate constants (k) for the reactions have been determined at 740 {+-} 5 Torr and 298 {+-} 5 K, and a number of reaction products were identified. From the results obtained in this investigation and previous studies, it was concluded that a typical atmospheric lifetime with respect to chemical reactions was only a few hours for pinonaldehyde, IPOH, and MVT but was much longer for nopinone with a lifetime of about 10 h.

  16. Waveform tomography in 2.5-D to appropriately handle 3-D geometry

    NASA Astrophysics Data System (ADS)

    Smithyman, B.; Clowes, R. M.

    2011-12-01

    In order to improve the tractability of waveform tomography when applied to field data acquired along a crooked-line, we implement 2.5-D forward modeling and inversion. Waveform tomography combines conventional velocity-model building (i.e. tomography) with full-waveform inversion to reconstruct an image of subsurface acoustic velocity. For reasons of computational efficiency, it is desirable to use 2-D full-waveform inversion when processing data acquired with 2-D seismic survey geometry. However, crooked-line acquisition results in a cross-line component of the source-receiver offset that cannot be accounted for by 2-D forward modeling. If the cross-line geometry components are significant, full-waveform inversion may be intractable. To address the latter difficulty, we first apply 3-D traveltime tomography to generate a 2-D cross-sectional initial velocity model by taking a representative average slice through the 3-D model. Then this initial model from traveltime inversion is iteratively updated by 2.5-D full-waveform inversion using a frequency-domain viscoacoustic implementation. The 2.5-D method generates waveform data by combining the solutions of multiple 2-D wave equation components. Each wavefield represents the solution of a modified wave equation in which the cross-line wavenumber takes a value between zero and ~ω/c. The results are combined by inverse Fourier transform in the cross-line coordinate. This produces a synthetic wavefield that is a solution to the 3-D viscoacoustic wave equation in a 2-D velocity model. Consequently, the 2.5-D synthetic wavefield better approximates seismic field data (including crooked-line geometry), when compared to a 2-D synthetic result. Cross-line source-receiver offsets can be accounted for by reconstructing the wavefield out-of-plane with respect to the source. The amplitude and phase of the wavefield are consistent with a 3-D solution in a model that is homogeneous in one direction. The 2-D model is ideally

  17. Investigation of Non-Magnetic Iron in LUTETIUM(2)IRON(3)SILICON(5) - Superconductors.

    NASA Astrophysics Data System (ADS)

    Xu, Youwen

    1987-03-01

    A focussed study on the effect of transition metal substitution for Fe in the compounds {rm Lu_2(Fe_{1-x}T_{x}) _3Si}_5 (Where T = Cr, Mn, Co, Ni Cu, and Ru) is reported. The effect of these transition metals on the superconducting transition temperature shows that Cr, Co, Ni and Ru all act as non-magnetic impurities. By fitting the experimental data {rm T _{c}/T_{co}} to Kaiser's equation, a good agreement with Kaiser's theory is obtained. The rate of suppression due to Co substitution is similar to that of Ru. Superconductivity persists ({rm T_{c}} = 0.49K) even when 10 at.% Co is substituted for Fe. In contrast, Mn and Cu act as magnetic impurities and suppress {rm T_{c}} in a way described by the theory of Abrikosov and Gor'kov. The molar magnetic susceptibility of {rm Lu_2Fe_3Si}_5 does not follow a Curie-Weiss law, but rather increases slightly as temperature increases. The addition of Ru lowers the value of chi{rm (T) }, but the overall shape of chi {rm (T)} is unchanged. In contrast, the substitution of the nominally magnetic transition metals Cr, Mn, Co and Ni for Fe causes chi{ rm (T)} to become more Curie-Weiss like. The magnetic susceptibility of the compound { rm Lu_2Co_3Si}_5 follows the Curie-Weiss law, while that of the compound {rm Lu_2Ru_3Si}_5 is diamagnetic. The electrical resistivity rho{ rm (T)} of the compound { rm Lu_2Fe_3Si}_5 is approximately quadratic in T at temperatures below 50 K and proportional to lnT at temperature above 100 K. The low temperature heat capacity data of the Co- and Ru-containing samples are similar and both fit to equations gamma{_ {s}T+beta_{s}T}^3 below {rm T_{c} } and gamma{_ {n}T+beta_{n}T^3+ alpha_{n}T}^5 above {rm T_{c}} in agreement with the heat capacity measurement by C. B. Vining for the compound {rm Lu_2Fe_3Si}_5. Increasing the concentration of Co or Ru lowers the Debye temperature and the electronic density of states at the Fermi level of the compounds and enhances the linear term in the superconducting

  18. Bandgap narrowing in the layered oxysulfide semiconductor Ba3Fe2O5Cu2S2: Role of FeO2 layer

    NASA Astrophysics Data System (ADS)

    Han, Zhang; Shifeng, Jin; Liwei, Guo; Shijie, Shen; Zhiping, Lin; Xiaolong, Chen

    2016-02-01

    A new layered Cu-based oxychalcogenide Ba3Fe2O5Cu2S2 has been synthesized and its magnetic and electronic properties were revealed. Ba3Fe2O5Cu2S2 is built up by alternatively stacking [Cu2S2]2- layers and iron perovskite oxide [(FeO2)(BaO)(FeO2)]2- layers along the c axis that are separated by barium ions with Fe3+ fivefold coordinated by a square-pyramidal arrangement of oxygen. From the bond valence arguments, we inferred that in layered CuCh-based (Ch = S, Se, Te) compounds the +3 cation in perovskite oxide sheet prefers a square pyramidal site, while the lower valence cation prefers the square planar sites. The studies on susceptibility, transport, and optical reflectivity indicate that Ba3Fe2O5Cu2S2 is an antiferromagnetic semiconductor with a Néel temperature of 121 K and an optical bandgap of 1.03 eV. The measurement of heat capacity from 10 K to room temperature shows no anomaly at 121 K. The Debye temperature is determined to be 113 K. Theoretical calculations indicate that the conduction band minimum is predominantly contributed by O 2p and 3d states of Fe ions that antiferromagnetically arranged in FeO2 layers. The Fe 3d states are located at lower energy and result in a narrow bandgap in comparison with that of the isostructural Sr3Sc2O5Cu2S2. Project supported by the National Natural Science Foundation of China (Grant Nos. 51472266, 51202286, and 91422303), the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (Grant No. XDB07020100) and the ICDD.

  19. Rapid synthesis and luminescence properties of Sr3SiO5:Eu2+ phosphors

    NASA Astrophysics Data System (ADS)

    Sun, Jiacheng; Mi, Xiaoyun; Ma, Jing; Su, Jiangang; Xia, Wei; Zhang, Lei; Bai, Zhaohui; Zhang, Xiyan

    2016-03-01

    Sr3SiO5:Eu2+ phosphors were synthesized rapidly through a microwave sintering method with the presence of activated carbon powder. The detailed composition and morphology were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The influences of sintering time, fluxing agent (BaF2) content and rare earth ion doping concentration on its photoluminescence (PL) properties were also investigated. It was clear in PL spectra that a broad emission band peaking at 570nm was obtained in as-prepared phosphors under a blue light excitation. Meanwhile, non-radiative transitions between Eu2+ ions in the Sr3SiO5 host had also been demonstrated to be attributable to dipole-dipole interactions, and the critical distance calculated by the quenching concentration was estimated to be 10.56 Å. The samples were uniform in diameter and regular in morphology. In other words, the Sr3SiO5:Eu2+ phosphors possessed a potential application for white light emitting diodes (LEDs).

  20. Anticancer activity of 5-benzylidene-2-phenylimino-1, 3-thiazolidin-4-one (BPT) analogs.

    PubMed

    Wu, S; Guo, W; Teraishi, F; Pang, J; Kaluarachchi, K; Zhang, L; Davis, J; Dong, F; Yan, B; Fang, B

    2006-11-01

    We recently identified two compounds of 5-benzylidene-2-phenylimino-1,3-thiazolidin-4-one (BPT) analog, 5-(4-methylbenzylidene)-2-phenylamino-1,3-thiazolidin-4-one (MMPT) and 5-(2,4-dihydroxybenzylidene)-2-phenylimino-1,3-thiazolidin-4-one (DBPT), that can effectively induce apoptosis in cancer cells but not in normal cells, independently of P-glycoprotein status. To further investigate the antitumor activity of BPT analogs, we obtained 18 commercially available analogs of BPT and synthesized 7 analogs in our lab, and analyzed their antitumor activity in various cancer cells, including paclitaxel- and vinorelbine-sensitive and -resistant human lung cancer cells. Two of the compounds were more potent than MMPT or DBPT in induction of apoptosis in certain cancer cell lines and remained tumor selective. Seven compounds did not induce any cytotoxic effects in any of the cell lines tested at the highest concentration tested (31 microM). The other compounds induced cytotoxic effects in some cancer cells but not in others or were less potent than MMPT and DBPT. Cell uptake studies showed that analogs that effectively induced cell killing in paclitaxel- and vinorelbine-resistant cells could be taken up easily by those cells despite their high levels of P-glycoprotein expression. These data further demonstrate that thiazolidinone analogs are not P-glycoprotein substrates and could be useful for treatment of P-glycoprotein overexpressing refractory cancers. PMID:17105441

  1. Synthesis of methylamino-2-phenyl-2-butyl-3,4,5-trimethoxybenzoate, the main bioactive metabolite of trimebutine maleate.

    PubMed

    Martin, A; Figadère, B; Saivin, S; Houin, G; Chomard, J M; Cahiez, G

    2000-06-01

    The first synthesis of the methylamino-2-phenyl-2-butyl-3,4,5-trimethoxybenzoate (desmethyltrimebutine) I is described. This compound is the main bioactive metabolite of trimebutine II (Debridat, CAS 39133-31-8), an antispasmodic widely used for intestinal diseases since 1969. It was used for pharmacokinetic and bioequivalence studies. PMID:10918948

  2. (1S*,2R*,3S*,4R*,5R*)-5-Tetra­decyloxy­methyl-7-oxabicyclo­[2.2.1]heptane-2,3-dicarb­oxy­lic anhydride

    PubMed Central

    Kelly, Colin N.; Sulon, Sarah M.; Pham, Lam N.; Xiang, Kang Rui; Sykora, Richard E.; Forbes, David C.

    2012-01-01

    In the title compound, C23H38O5, the oxabicyclo­[2.2.1]heptane-2,3-dicarb­oxy­lic anhydride unit has a normal geometry and the tetra­decoxymethyl side chain is fully extended. In the crystal, mol­ecules are linked head-to-head by C—H⋯O hydrogen bonds, forming two-dimensional networks propagating along the a and c-axis directions. PMID:23476206

  3. Bis(2,6-diamino-3,5-dibromo-pyridinium) hexa-bromidostannate(IV).

    PubMed

    Al-Far, Rawhi H; Haddad, Salim F; Ali, Basem Fares

    2009-01-01

    The asymmetric unit of the title compound, (C(5)H(6)Br(2)N(3))(2)[SnBr(6)], contains one cation and one half-anion in which the Sn atom is located on a crystallographic centre of inversion and is in a quasi-octa-hedral geometry. The crystal structure is assembled via hydrogen-bonding inter-actions of two kinds, N(pyridine/amine)-H⋯Br-Sn, along with C-Br⋯Br-Sn interactions [3.4925 (19) Å]. The cations are involved in π-π stacking, which adds an extra supra-molecularity as it presents a strong case of offset-face-to-face motifs [centroid-centroid distance = 3.577 (3) Å]. The inter-molecular hydrogen bonds, short Br⋯Br inter-actions and π-π stacking result in the formation of a three-dimensional supra-molecular architecture. PMID:21583810

  4. Ion transport studies on Li2O-PbO-B2O3-P2O5 glass system

    NASA Astrophysics Data System (ADS)

    Muralidhara, R. S.; Anavekar, R. V.

    2009-07-01

    Electrical conductivity of Li+ ion conducting borophosphate glass system with the general formula xLi2O -10PbO-(90-x) [55B2O3 + 45 P2O5] where x=20, 25, 30 and 35 has been carried out both as a function of temperature and frequency in the temperature range 303K to 503K and over frequencies 20 Hz to 12 MHz. The dc conductivities show Arrhenius behaviour while exhibiting composition dependence. Edc estimated from Arrhenius plots varies from 0.82 eV 0.88 eV. The ac conductivity behaviour has been analyzed using a single power law. The exponent `s' obtained from the power law fits is found to have values ranging from 0.45 to 0.84.in these glasses and shows moderate temperature dependence The stretched exponent β also is seen to vary slightly with temperature. Scaling behaviour also has been carried out using the reduced plots of conductivity and frequency. The time-temperature superposition of data points is found to be satisfactory indicating that the ion transport mechanism remains the same in the entire range of temperatures and compositions studied. The results have been explained considering the borophosphate network and the role of Li2O as a glass modifier.

  5. X-ray diffraction investigation of 1-phenyl-3-isopropyl-5-(benzothiazol-2-yl)formazan

    SciTech Connect

    Slepukhin, P. A. Pervova, I. G.; Rezinskikh, Z. G.; Lipunova, G. N.; Gorbatenko, Yu. A.; Lipunov, I. N.

    2008-01-15

    The crystal structure of 1-phenyl-3-isopropyl-5-(benzothiazol-2-yl)formazan is investigated using X-ray diffraction. The compound crystallizes in the form of two crystallographically independent molecules (A and B) in identical conformations that are stabilized by intermolecular hydrogen bonds. The intermolecular hydrogen bonds N-H-N (N-N, 2.892 and 2.939 A) link molecules into AB dimers. Both molecules have a flattened structure, except for the isopropyl fragment. The bonds in the formazan chains are delocalized. Molecules A and B have close geometric characteristics.

  6. HNO3, N2O5 and CIONO2 Enhancements after the October-November 2003 Solar Proton Events

    NASA Technical Reports Server (NTRS)

    Lopez-Puertas, M.; Funke, B.; Gil-Lopez, S.; Tsidu, G. Mengistu; Fischer, H.; Jackman, C. H.

    2005-01-01

    The large solar storm in October-November 2003 produced enormous amounts of high-energy protons which reached the Earth and penetrated into the middle atmosphere in the polar regions. At this time, the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on board the Environmental Satellite (ENVISAT) was observing the atmosphere in the 6-68 km altitude range. MIPAS observed significant enhancements of the NO(y) components HNO3, N2O5 and CIONO2 in the Northern polar stratosphere after the intense solar proton events. Two distinct HNO3 enhancements were observed. An instantaneous increase of 1-2 ppbv was observed immediately after the SPEs and is attributed to gas-phase chemistry: NO2 + OH + M yields HNO3 + M, accelerated by SPE-produced excess OH. A very large second increase of 1- 5 ppbv started around 10 November and lasted until the end of December. It is attributed to NO(x) (NO+NO2) produced in the mesosphere during the major SPEs in late October/early November and then transported downwards during November and December, partially converted to N2O5 in the upper stratosphere, which finally formed HNO3 via ion cluster reactions. N2O5 was observed to increase by 0.1-0.4 ppbv 1-3 days after the major SPEs and reached down to 30 km altitude. A second, more pronounced N2O5 enhancement of up to 1.2 ppbv at 40 km appeared about 12-13 days after the major SPEs. With a delay of 1-2 days after the major SPEs CIONO2 increased by up to 0.4 ppbv (40%) at 32 km altitude. NO(y) enhancements in the Southern hemisphere were generally less pronounced.

  7. Heterogeneous oxidation kinetics of organic biomass burning aerosol surrogates by O3, NO2, N2O5, and NO3.

    PubMed

    Knopf, Daniel A; Forrester, Seanna M; Slade, Jonathan H

    2011-12-21

    The reactive uptake coefficients (γ) of O(3), NO(2), N(2)O(5), and NO(3) by levoglucosan, abietic acid, nitroguaiacol, and an atmospherically relevant mixture of those species serving as surrogates for biomass burning aerosol have been determined employing a chemical ionization mass spectrometer coupled to a rotating-wall flow-tube reactor. γ of O(3), NO(2), N(2)O(5), and NO(3) in the presence of O(2) are in the range of 1-8 × 10(-5), <10(-6)-5 × 10(-5), 4-6 × 10(-5), and 1-26 × 10(-3), respectively, for the investigated organic substrates. Within experimental uncertainties the uptake of NO(3) was not sensitive to the presence of water vapour ( <0.5% relative humidity). [corrected]. NO(3) uptake experiments involving substrates of levoglucosan, abietic acid, and the mixture exhibit an initial strong uptake of NO(3) followed by NO(3) gas-phase recovery as a function of NO(3) exposure. In contrast, the uptake of NO(3) by nitroguaiacol continuously proceeds at the same efficiency for investigated NO(3) exposures. The derived oxidative power, i.e. the product of γ and atmospheric oxidant concentration, for applied oxidants is similar or significantly larger in magnitude than for OH, emphasizing the potential importance of these oxidants for particle oxidation. Estimated atmospheric lifetimes for the topmost organic layer with respect to O(3), NO(2), N(2)O(5), and NO(3) oxidation for typical polluted conditions range between 1-112 min, indicating the potential for significant chemical transformation during atmospheric transport. The contact angles determined prior to, and after heterogeneous oxidation by NO(3), representative of 50 ppt for 1 day, do not decrease and thus do not indicate a significant increase in hygroscopicity with potential impacts on water uptake and cloud formation processes. PMID:22020363

  8. One-pot Sequential Reactions Featuring a Copper-catalyzed Amination Leading to Pyrido[2',1':2,3]imidazo[4,5-c]quinolines and Dihydropyrido[2',1':2,3]imidazo[4,5-c]quinolines.

    PubMed

    Fan, Xue-Sen; Zhang, Ju; Li, Bin; Zhang, Xin-Ying

    2015-06-01

    Tetracyclic skeletons combining an imidazo[1,2-a]pyridine moiety with a quinoline framework such as pyrido[2',1':2,3]imidazo[4,5-b]quinoline are stimulating increasing interests since they are close isosteres of a series of powerful antiproliferative compounds. In this paper, we report a novel methodology for the synthesis of pyrido[2',1':2,3]imidazo[4,5-c]quinolines through one-pot sequential reactions of commercially available or readily obtainable 2-aminopyridines, 2-bromophenacyl bromides, aqueous ammonia, and aldehydes. Moreover, dihydropyrido[2',1':2,3]imidazo[4,5-c]quinolines could also be obtained in a similar manner by using various ketones as the substrates in place of aldehydes. Notably, the whole procedure combines condensation/amination/cyclization reactions in one pot to give complex compounds in a simple and practical manner. Compared with literature methods, the synthetic strategy reported herein has the advantages of readily available starting materials, structural diversity of products, good functional group tolerance, and obviation of step-by-step operations. PMID:25865134

  9. Chemical destruction of CH3I, C2H5I, 1-C3H7I, and 2-C3H7I in saltwater

    NASA Astrophysics Data System (ADS)

    Jones, Charlotte E.; Carpenter, Lucy J.

    2007-07-01

    Destruction of volatile iodocarbons in the oceans can potentially play an important role in determining the predominant chemical forms of iodine emitted to the atmosphere. Here we report chlorination and hydrolysis removal rates for CH3I, C2H5I, 1-C3H7I, and 2-C3H7I relevant to oceanic conditions. We have used these rates to calculate oceanic lifetimes for each iodocarbon with respect to total chemical destruction, as a function of seawater temperature. The resulting lifetimes are compared to typical iodocarbon oceanic residence times with respect to volatilization to the MBL. The rate of destruction of 2-C3H7I is much more rapid than chemical removal of the primary alkyl iodides, potentially explaining previous observations of lower 2-C3H7I concentrations in seawater compared to 1-C3H7I. Finally, in light of these results, we briefly discuss the potential impact of rising global seawater temperatures on oceanic iodocarbon concentrations.

  10. Luminescence of phosphorus containing oxide materials: Crystalline SiO2-P and 3P2O5ṡ7SiO2; CaOṡP2O5; SrOṡP2O5 glasses

    NASA Astrophysics Data System (ADS)

    Trukhin, A. N.; Smits, K.; Jansons, J.; Berzins, D.; Chikvaidze, G.; Griscom, D. L.

    2014-10-01

    Luminescence of phosphate glasses such as CaOṡP2O5 and SrOṡP2O5 is compared with that of phosphorus doped crystalline α-quartz and phosphosilicate glass with content 3P2O5ṡ7SiO2. Water & OH groups are found by IR spectra in these materials. The spectrum of luminescence contains many bands in the range 1.5 - 5.5 eV. The luminescence bands in UV range at 4.5-5 eV are similar in those materials. Decay duration in exponential approximation manifests a time constant about 37 ns. Also a component in μs range was detected. PL band of μs component is shifted to low energy with respect to that of ˜37 ns component. This shift is about 0.6 eV. It is explained as singlet-triplet splitting of excited state. Below 14 K increase of luminescence kinetics duration in μs range was observed and it was ascribed to zero magnetic field splitting of triplet excited state of the center. Yellow-red luminescence was induced by irradiation in phosphorus doped crystalline α-quartz, phosphosilicate glasses. The yellowl uminescence contains two bands at 600 and 740 nm. Their decay is similar under 193 nm laser and may be fitted with the first order fractal kinetics or stretched exponent. Thermally stimulated luminescence contains only band at 600 nm. The 248 nm laser excites luminescence at 740 nm according to intra center process with decay time constant about 4 ms at 9 K. Both type of luminescence UV and yellow were ascribed to different defects containing phosphorus. P-doped α-quartz sample heated to 550 co become opalescent. Ir spectra related to water & OH groups are changed. Photoluminescence intensity of all three bands, UV (250 nm), yellow (600 nm) and red (740 nm) strongly diminished and disappeared after heating to 660 C°. Radiation induced red luminescence of non-bridging oxygen luminescence center (NBO) appeared in crystal after heat treatment. We had observed a crystalline version of this center (l. Skuja et al, Nuclear Instruments and Methods in Physics Research B

  11. Synthesis of novel 2H,5H-Dihydrofuran-3-yl Ketones via ISNC reactions

    PubMed Central

    Grandbois, Matthew L.; Betsch, Kelsie J.; Buchanan, William D.; Duffy-Matzner, Jetty L.

    2009-01-01

    Unique 1-[2H,5H-dihydrofur-3-yl]ketones have been synthesized from propargylic nitroethers via intramolecular cycloadditions involving silyl nitronates. Various substituent groups were placed on the 2 and 5 positions of the dihydrofuran rings. We examined the scope of the long-range coupling in proton NMR of the oxo-dihydrofuran products. The identities of the diastereomers resulting from the Michael Addition/cycloaddition reactions were tentatively assigned for the first time. CAChe MNDO PM5 and CONFLEX programs were engaged to assist with the identification of these stereoisomers. The reaction times and conditions for these oxo-dihydrofurans were found to be different than that of the published dihydrofuranals, which led us to propose a different mechanism. PMID:20161382

  12. 3,5-T2 is an alternative ligand for the thyroid hormone receptor β1.

    PubMed

    Mendoza, A; Navarrete-Ramírez, P; Hernández-Puga, G; Villalobos, P; Holzer, G; Renaud, J P; Laudet, V; Orozco, A

    2013-08-01

    Several liganded nuclear receptors have alternative ligands acting in a tissue-specific fashion and playing important biological roles. We present evidence that 3,5-diiodothyronine (T(2)), a naturally occurring iodothyronine that results from T(3) outer-ring deiodination, is an alternative ligand for thyroid hormone receptor β1 (TRβ1). In tilapia, 2 TRβ isoforms differing by 9 amino acids in the ligand-binding domain were cloned. Binding and transactivation studies showed that T(2) activates the human and the long tilapia TRβ1 isoform, but not the short one. A chimeric human TRβ1 (hTRβ1) that contained the 9-amino-acid insert showed no response to T(2), suggesting that the conformation of the hTRβ1 naturally allows T(2) binding and that other regions of the receptor are implicated in TR activation by T(2). Indeed, further analysis showed that the N terminus is essential for T(2)-mediated transactivation but not for that by T(3) in the long and hTRβ1, suggesting a functional interaction between the N-terminal domain and the insertion in the ligand-binding domain. To establish the functional relevance of T(2)-mediated TRβ1 binding and activation, mRNA expression and its regulation by T(2) and T(3) was evaluated for both isoforms. Our data show that long TRβ1expression is 10(6)-fold higher than that of the short isoform, and T(3) and T(2) differentially regulate the expression of these 2 TRβ1 isoforms in vivo. Taken together, our results prompted a reevaluation of the role and mechanism of action of thyroid hormone metabolites previously believed to be inactive. More generally, we propose that classical liganded receptors are only partially locked to very specific ligands and that alternative ligands may play a role in the tissue-specific action of receptors. PMID:23736295

  13. Fatigue in 0.5Li2MnO3:0.5Li(Ni1/3Co1/3Mn1/3)O2 positive electrodes for lithium ion batteries

    NASA Astrophysics Data System (ADS)

    Riekehr, Lars; Liu, Jinlong; Schwarz, Björn; Sigel, Florian; Kerkamm, Ingo; Xia, Yongyao; Ehrenberg, Helmut

    2016-09-01

    Two different Li-rich nickel-cobalt-manganese-oxide (Li-rich NCM) active materials with the same nominal composition 0.5Li2MnO3:0.5Li(Ni1/3Co1/3Mn1/3)O2 but different pristine nano structure have been analyzed structurally and electrochemically in different cycling states. For structural characterization, transmission electron microscopy (TEM) and high resolution synchrotron powder diffraction (S-XRD) experiments were conducted. The changes in structure with increasing cycle number are correlated with characteristic features in the corresponding electrochemical dQ/dV-profiles that were obtained by galvanostatically cycling the two different active materials. The presented data demonstrates that structural changes upon cycling, e.g. LiMnO2 and spinel formation, strongly depend on the degree oxygen is involved in the reversible charge compensation for delithiation/lithiation. According to our data, firstly a twin-like environment with nanometer dimensions is formed within the R-3m matrix during the initial cycle, which then gradually transforms into a spinel-like structure with increasing cycle number. As another result, we can show that Li2MnO3 to LiMnO2 transformation is not directly dependent in the irreversible oxygen loss in the first cycle but more importantly on transition metal migration. A model is presented explaining the dependency of LiMnO2 and spinel formation on the ability of Li-rich active materials to include oxygen in the charge compensation process.

  14. α5β1 integrin recycling promotes Arp2/3-independent cancer cell invasion via the formin FHOD3.

    PubMed

    Paul, Nikki R; Allen, Jennifer L; Chapman, Anna; Morlan-Mairal, Maria; Zindy, Egor; Jacquemet, Guillaume; Fernandez del Ama, Laura; Ferizovic, Nermina; Green, David M; Howe, Jonathan D; Ehler, Elisabeth; Hurlstone, Adam; Caswell, Patrick T

    2015-09-14

    Invasive migration in 3D extracellular matrix (ECM) is crucial to cancer metastasis, yet little is known of the molecular mechanisms that drive reorganization of the cytoskeleton as cancer cells disseminate in vivo. 2D Rac-driven lamellipodial migration is well understood, but how these features apply to 3D migration is not clear. We find that lamellipodia-like protrusions and retrograde actin flow are indeed observed in cells moving in 3D ECM. However, Rab-coupling protein (RCP)-driven endocytic recycling of α5β1 integrin enhances invasive migration of cancer cells into fibronectin-rich 3D ECM, driven by RhoA and filopodial spike-based protrusions, not lamellipodia. Furthermore, we show that actin spike protrusions are Arp2/3-independent. Dynamic actin spike assembly in cells invading in vitro and in vivo is regulated by Formin homology-2 domain containing 3 (FHOD3), which is activated by RhoA/ROCK, establishing a novel mechanism through which the RCP-α5β1 pathway reprograms the actin cytoskeleton to promote invasive migration and local invasion in vivo. PMID:26370503

  15. α5β1 integrin recycling promotes Arp2/3-independent cancer cell invasion via the formin FHOD3

    PubMed Central

    Paul, Nikki R.; Allen, Jennifer L.; Chapman, Anna; Morlan-Mairal, Maria; Zindy, Egor; Jacquemet, Guillaume; Fernandez del Ama, Laura; Ferizovic, Nermina; Green, David M.; Howe, Jonathan D.; Ehler, Elisabeth; Hurlstone, Adam

    2015-01-01

    Invasive migration in 3D extracellular matrix (ECM) is crucial to cancer metastasis, yet little is known of the molecular mechanisms that drive reorganization of the cytoskeleton as cancer cells disseminate in vivo. 2D Rac-driven lamellipodial migration is well understood, but how these features apply to 3D migration is not clear. We find that lamellipodia-like protrusions and retrograde actin flow are indeed observed in cells moving in 3D ECM. However, Rab-coupling protein (RCP)-driven endocytic recycling of α5β1 integrin enhances invasive migration of cancer cells into fibronectin-rich 3D ECM, driven by RhoA and filopodial spike-based protrusions, not lamellipodia. Furthermore, we show that actin spike protrusions are Arp2/3-independent. Dynamic actin spike assembly in cells invading in vitro and in vivo is regulated by Formin homology-2 domain containing 3 (FHOD3), which is activated by RhoA/ROCK, establishing a novel mechanism through which the RCP–α5β1 pathway reprograms the actin cytoskeleton to promote invasive migration and local invasion in vivo. PMID:26370503

  16. Sequential Injection/Electrochemical Immunoassay for Quantifying the Pesticide Metabolite 3, 5, 6-Trichloro-2-Pyridinol

    SciTech Connect

    Liu, Guodong; Riechers, Shawn L.; Timchalk, Chuck; Lin, Yuehe

    2005-12-04

    An automated and sensitive sequential injection electrochemical immunoassay was developed to monitor a potential insecticide biomarker, 3, 5, 6-trichloro-2-pyridinol. The current method involved a sequential injection analysis (SIA) system equipped with a thin-layer electrochemical flow cell and permanent magnet, which was used to fix 3,5,6-trichloro-2-pyridinol (TCP) antibody coated magnetic beads (TCP-Ab-MBs) in the reaction zone. After competitive immunoreactions among TCP-Ab-MBs, TCP analyte, and horseradish peroxidase (HRP) labeled TCP, a 3, 3?, 5, 5?-tetramethylbenzidine dihydrochloride and hydrogen peroxide (TMB-H2O2) substrate solution was injected to produce an electroactive enzymatic product. The activity of HRP tracers was monitored by a square wave voltammetric scanning electroactive enzymatic product in the thin-layer flow cell. The voltammetric characteristics of the substrate and the enzymatic product were investigated under batch conditions, and the parameters of the immunoassay were optimized in the SIA system. Under the optimal conditions, the system was used to measure as low as 6 ng L-1 (ppt) TCP, which is around 50-fold lower than the value indicated by the manufacturer of the TCP RaPID Assay? kit (0.25 ug/L, colorimetric detection). The performance of the developed immunoassay system was successfully evaluated on tap water and river water samples spiked with TCP. This technique could be readily used for detecting other environmental contaminants by developing specific antibodies against contaminants and is expected to open new opportunities for environmental and biological monitoring.

  17. Spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB

    DOEpatents

    Harris, B.W.

    1984-11-29

    A simple, sensitive and specific spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB, is described. Upon the application of the composition of matter of the subject invention to samples containing in excess of 0.1 mg of this explosive, a bright orange color results. Interfering species such as TNT and Tetryl can be removed by first treating the sample with a solvent which does not dissolve the TATB, but readily dissolves these interfering explosives.

  18. Spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB

    DOEpatents

    Harris, Betty W.

    1986-01-01

    A simple, sensitive and specific spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB, is described. Upon the application of the composition of matter of the present invention to samples containing in excess of 0.1 mg of this explosive, a bright orange color results. Interfering species such as TNT and Tetryl can be removed by first treating the sample with a solvent which does not dissolve much of the TATB, but readily dissolves these explosives.

  19. Preparations, structures and properties of heterobimetallic complexes based on tetrahydrofuran-2,3,4,5-tetracarboxylate

    SciTech Connect

    Jia, Tian-Jing; Li, Shu-Mu; Cao, Wei; Li, Li-Cun; Zheng, Xiang-Jun; Yuan, Da-Qiang

    2013-05-01

    Transition heterobimetallic metal-organic frameworks based on tetrahydrofuran-2,3,4,5-tetracarboxylicate (FTA), namely [M(H₂O)₆][Cu₂M(FTA)₂(H₂O)₂]·4H₂O [M=Mn (1), Co (2)], and [CuZn(FTA)(H₂O)₅]·H₂O (3) have been synthesized and characterized. Single-crystal X-ray diffraction indicates that complexes 1 and 2 are isomorphic. In 1 and 2, FTA ligand links the metal ions to a 2-D wave-like negative-charged layer with a topology of (4;6²)₂(4;6³;8²)₂(6). They possess 1-D channels with [M(H₂O)₆]²⁺ and lattice water molecules enclathrated. While in the complex 3, Cu²⁺ and Zn²⁺ ions are bridged by FTA to a 2-D neutral layer structure with a (8)₂(8⁴;12²) topology. Magnetic properties of 1–3 were analyzed in connection with their structures, which show that there exist weak antiferromagnetic interactions between metal ions. - Graphical abstract: Three heterobimetallic MOFs were constructed through the size-selectivity of TFA coordination sites for different transition metal ions based on the concept of “Hard and Soft Acids and Bases”. Highlights: • Complexes 1 and 3 contain 2-D wave-like negative-charged layers. • Complex 2 is a 2-D neutral layer structure with a (8)₂(8⁴;12²) topology. • Complexes 1–3 are the first example of heterobimetallic MOFs based on FTA. • The coordination sites of FTA show size-selectivity to metal ions.

  20. Investigation of the 2p3/2-3d5/2 line emission of Au53+ -- Au69+ for diagnosing high energy density plasmas

    SciTech Connect

    Brown, G V; Hansen, S B; Trabert, E; Beiersdorfer, P; Widmann, K; Chen, H; Chung, H K; Clementson, J T; Gu, M F; Thorn, D B

    2008-01-29

    Measurements of the L-shell emission of highly charged gold ions were made under controlled laboratory conditions using the SuperEBIT electron beam ion trap, allowing detailed spectral observations of lines from ironlike Au{sup 53+} through neonlike Au{sup 69+}. Using atomic data from the Flexible Atomic Code, we have identified strong 3d{sub 5/2} {yields} 2p{sub 3/2} emission features that can be used to diagnose the charge state distribution in high energy density plasmas, such as those found in the laser entrance hole of hot hohlraum radiation sources. We provide collisional-radiative calculations of the average ion charge as a function of temperature and density, which can be used to relate charge state distributions inferred from 3d{sub 5/2} {yields} 2p{sub 3/2} emission features to plasma conditions, and investigate the effects of plasma density on calculated L-shell Au emission spectra.

  1. Crystal structure of (+)-methyl (E)-3-[(2S,4S,5R)-2-amino-5-hy-droxy-meth-yl-2-tri-chloro-methyl-1,3-dioxolan-4-yl]-2-methyl-prop-2-enoate.

    PubMed

    Oishi, Takeshi; Yasushima, Daichi; Yuasa, Kihiro; Sato, Takaaki; Chida, Noritaka

    2016-03-01

    In the title compound, C10H14Cl3NO5, the five-membered dioxolane ring adopts an envelope conformation. The C atom at the flap, which is bonded to the hy-droxy-methyl substituent, deviates from the mean plane of other ring atoms by 0.357 (5) Å. There are two intra-molecular hydrogen bonds (O-H⋯N and N-H⋯O) between the hy-droxy and amino groups, so that O- and N-bound H atoms involved in these hydrogen bonds are each disordered with equal occupancies of 0.50. The methyl 2-methyl-prop-2-enoate substituent also shows a disordered structure over two sets of sites with refined occupancies of 0.482 (5) and 0.518 (5). In the crystal, mol-ecules are connected into a dimer by an O-H⋯O hydrogen bond. The dimers are further linked by N-H⋯O, C-H⋯N and C-H⋯O inter-actions, extending a sheet structure parallel to ([Formula: see text]01). PMID:27006804

  2. Metallic Borides, La2Re3B7 and La3Re2B5, Featuring Extensive Boron-Boron Bonding.

    PubMed

    Bugaris, Daniel E; Malliakas, Christos D; Chung, Duck Young; Kanatzidis, Mercouri G

    2016-02-15

    La2Re3B7 and La3Re2B5 have been synthesized in single-crystalline form from a molten La/Ni eutectic at 1000 °C in the first example of the flux crystal growth of ternary rare-earth rhenium borides. Both compounds crystallize in their own orthorhombic structure types, with La2Re3B7 (space group Pcca) having lattice parameters a = 7.657(2) Å, b = 6.755(1) Å, and c = 11.617(2) Å, and La3Re2B5 (space group Pmma) having lattice parameters a = 10.809(2) Å, b = 5.287(1) Å, and c = 5.747(1) Å. The compounds possess three-dimensional framework structures that are built up from rhenium boride polyhedra and boron-boron bonding. La3Re2B5 features fairly common B2 dumbbells, whereas La2Re3B7 has unique one-dimensional subunits composed of alternating triangular B3 and trans-B4 zigzag chain fragments. Also observed in La3Re2B5 is an unusual coordination of B by an octahedron of La atoms. Electronic band structure calculations predict that La2Re3B7 is a semimetal, which is observed in the electrical resistivity data as measured on single crystals, with behavior obeying the Bloch-Grüneisen model and a room-temperature resistivity ρ300 K of ∼375 μΩ cm. The electronic band structure calculations also suggest that La3Re2B5 is a regular metal. PMID:26812202

  3. Synthesis, Antimitotic and Antivascular Activity of 1-(3′,4′,5′-Trimethoxybenzoyl)-3-arylamino-5-amino-1,2,4-triazoles

    PubMed Central

    Romagnoli, Romeo; Baraldi, Pier Giovanni; Salvador, Maria Kimatrai; Prencipe, Filippo; Bertolasi, Valerio; Cancellieri, Michela; Brancale, Andrea; Hamel, Ernest; Castagliuolo, Ignazio; Consolaro, Francesca; Porcú, Elena; Basso, Giuseppe; Viola, Giampietro

    2014-01-01

    A new class of compounds that incorporated the structural motif of the 1-(3′,4′,5′-trimethoxtbenzoyl)-3-arylamino-5-amino-1,2,4-triazole molecular skeleton was synthesized and evaluated for their antiproliferative activity in vitro, interactions with tubulin, and cell cycle effects. The most active agent, 3c, was evaluated for antitumor activity in vivo. Structure-activity relationships were elucidated with various substituents on the phenyl ring of the anilino moiety at the C-3 position of the 1,2,4-triazole ring. The best results for inhibition of cancer cell growth were obtained with the p-Me, m,p-diMe, and p-Et phenyl derivatives 3c, 3e, and 3f, respectively, and overall, these compounds were more or less as active as CA-4. Their vascular disrupting activity was evaluated in HUVEC cells, with compound 3c showing activity comparable with that of CA-4. Compound 3c almost eliminated the growth of syngeneic hepatocellular carcinoma in Balb/c mice, suggesting that 3c could be a new antimitotic agent with clinical potential. PMID:25025853

  4. 21 CFR 73.3115 - 2-[[2,5-Diethoxy-4-[(4-methylphenyl)thiol]phenyl]azo]-1,3,5-benzenetriol.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (hydrophilic) contact lenses. (b) Uses and restrictions. The color additive 2- phenyl]azo]-1,3,5-benzenetriol may be safely used to mark soft (hydrophilic) contact lenses with the letter R or the letter L for... exceed 1.1×10−7 grams in a soft (hydrophilic) contact lens. (2) When used as specified in the...

  5. 21 CFR 73.3115 - 2-[[2,5-Diethoxy-4-[(4-methylphenyl)thiol]phenyl]azo]-1,3,5-benzenetriol.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (hydrophilic) contact lenses. (b) Uses and restrictions. The color additive 2- phenyl]azo]-1,3,5-benzenetriol may be safely used to mark soft (hydrophilic) contact lenses with the letter R or the letter L for... exceed 1.1×10−7 grams in a soft (hydrophilic) contact lens. (2) When used as specified in the...

  6. 21 CFR 73.3115 - 2-[[2,5-Diethoxy-4-[(4-methylphenyl)thiol]phenyl]azo]-1,3,5-benzenetriol.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (hydrophilic) contact lenses. (b) Uses and restrictions. The color additive 2- phenyl]azo]-1,3,5-benzenetriol may be safely used to mark soft (hydrophilic) contact lenses with the letter R or the letter L for... exceed 1.1×10−7 grams in a soft (hydrophilic) contact lens. (2) When used as specified in the...

  7. 21 CFR 73.3115 - 2-[[2,5-Diethoxy-4-[(4-methylphenyl)thiol]phenyl]azo]-1,3,5-benzenetriol.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false 2- phenyl]azo]-1,3,5-benzenetriol. 73.3115 Section 73.3115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3115 2-...

  8. 21 CFR 73.3115 - 2-[[2,5-Diethoxy-4-[(4-methylphenyl)thiol]phenyl]azo]-1,3,5-benzenetriol.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false 2- phenyl]azo]-1,3,5-benzenetriol. 73.3115 Section 73.3115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Medical Devices § 73.3115 2-...

  9. Drosophila SMN complex proteins Gemin2, Gemin3, and Gemin5 are components of U bodies

    SciTech Connect

    Cauchi, Ruben J.; Sanchez-Pulido, Luis; Liu, Ji-Long

    2010-08-15

    Uridine-rich small nuclear ribonucleoproteins (U snRNPs) play key roles in pre-mRNA processing in the nucleus. The assembly of most U snRNPs takes place in the cytoplasm and is facilitated by the survival motor neuron (SMN) complex. Discrete cytoplasmic RNA granules called U bodies have been proposed to be specific sites for snRNP assembly because they contain U snRNPs and SMN. U bodies invariably associate with P bodies, which are involved in mRNA decay and translational control. However, it remains unknown whether other SMN complex proteins also localise to U bodies. In Drosophila there are four SMN complex proteins, namely SMN, Gemin2/CG10419, Gemin3 and Gemin5/Rigor mortis. Drosophila Gemin3 was originally identified as the Drosophila orthologue of human and yeast Dhh1, a component of P bodies. Through an in silico analysis of the DEAD-box RNA helicases we confirmed that Gemin3 is the bona fide Drosophila orthologue of vertebrate Gemin3 whereas the Drosophila orthologue of Dhh1 is Me31B. We then made use of the Drosophila egg chamber as a model system to study the subcellular distribution of the Gemin proteins as well as Me31B. Our cytological investigations show that Gemin2, Gemin3 and Gemin5 colocalise with SMN in U bodies. Although they are excluded from P bodies, as components of U bodies, Gemin2, Gemin3 and Gemin5 are consistently found associated with P bodies, wherein Me31B resides. In addition to a role in snRNP biogenesis, SMN complexes residing in U bodies may also be involved in mRNP assembly and/or transport.

  10. Raman, dielectric and AC-conductivity behavior of Dy2O3 contained K0.5Na0.5NbO3 ceramics

    NASA Astrophysics Data System (ADS)

    Mahesh, P.; Pamu, D.

    2016-05-01

    Lead-free piezoelectric (K0.5Na0.5)NbO3+ x wt% Dy2O3 (x = 0 - 1.5) (KNND) ceramics have been prepared by solid state reaction method. The effect of Dy2O3 on the dielectric and electrical conductivity responses of KNN ceramics were investigated in a broad temperature (from 133 K to 673 K) and frequency (106 Hz to 108 Hz) range. Temperature dependent dielectric analysis revealed that the polymorphic phase transition orthorhombic to tetragonal transition temperature (TO-T) shifted from 199°C to room temperature with enhanced dielectric permittivity (ɛ' = 994) with the addition of Dy2O3. The effect of Dy2O3 on structural properties of KNND ceramics are analyzed interms of changes in the internal modes of NbO6 octahedra by using Raman spectroscopy. Temperature dependent (133 K - 306 K) AC-conductivity follows the variable range hopping mechanism in different temperature regimes.

  11. Incommensurate Magnetic Structure in the Cubic Noncentrosymmetric Ternary Compound Pr5Ru3Al2

    NASA Astrophysics Data System (ADS)

    Makino, Koya; Okuyama, Daisuke; Avdeev, Maxim; Sato, Taku J.

    2016-07-01

    Magnetic susceptibility and neutron powder diffraction experiments have been performed on the noncentrosymmetric ternary compound Pr5Ru3Al2. The previously reported ferromagnetic transition at 24 K was not detected in our improved-quality samples. Instead, magnetic ordering was observed in the DC magnetic susceptibility at T{c} ≃ 3.8 K. The neutron powder diffraction experiment further indicates that an incommensurate magnetic structure is established below Tc with the magnetic modulation vector {{q}} ≃ (0.066,0.066,0.066) (r.l.u.). A candidate for the magnetic structure is proposed using representation analysis.

  12. 40 CFR 721.7280 - 1,3-Propanediamine, N,N′-1,2-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-ethanediylbis-, polymer with 2,4,6-trichloro-1,3,5-triazine, reaction products with N-butyl-2,2,6,6-tetramethyl... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.7280 1,3-Propanediamine,...

  13. Crystal structure of 1-methyl-3-([2,2-dimethyl-4,6-dioxo-1,3-dioxane-5-ylidene]methyl)urea

    SciTech Connect

    Habibi, A. Ghorbani, H. S.; Bruno, G.; Rudbari, H. A.; Valizadeh, Y.

    2013-12-15

    The crystal structure of 1-Methyl-3-([2,2-dimethyl-4,6-dioxo-1,3-dioxane-5-ylidene]methyl)urea (C{sub 9}H{sub 12}N{sub 2}O{sub 5}) has been determined by single crystal X-ray diffraction analysis. The crystals are monoclinic, a = 5.3179(2), b = 18.6394(6), c =10.8124(3) Å, β = 100.015(2)°, Z = 4, sp. gr. P2{sub 1}/c, R = 0.0381 for 2537 reflections with I > 2σ(I). Except for C(CH{sub 3}){sub 2} group, the molecule is planar. The structure is stabilized by inter- and intramolecular N-H...O hydrogen bonds and weak C-H...O interactions.

  14. Efficient white light emission by upconversion in Yb(3+)-, Er(3+)- and Tm(3+)-doped Y2BaZnO5.

    PubMed

    Etchart, Isabelle; Bérard, Mathieu; Laroche, Marine; Huignard, Arnaud; Hernández, Ignacio; Gillin, William P; Curry, Richard J; Cheetham, Anthony K

    2011-06-14

    We report efficient white upconversion luminescence in Yb(3+)-, Er(3+)- and Tm(3+)-doped monophasic and biphasic Y(2)BaZnO(5) phosphors under 977 nm near-infrared excitation and at low excitation power densities (down to ∼25 mW mm(-2)). PMID:21544288

  15. CHRNA3/5, IREB2, and ADCY2 Are Associated with Severe Chronic Obstructive Pulmonary Disease in Poland

    PubMed Central

    Zielinski, Jan; Wan, Emily S.; Hersh, Craig P.; Castaldi, Peter J.; Schwinder, Eric; Hawrylkiewicz, Iwona; Sliwinski, Pawel; Cho, Michael H.; Silverman, Edwin K.

    2012-01-01

    We examined the association between single-nucleotide polymorphisms (SNPs) previously associated with chronic obstructive pulmonary disease (COPD) and/or lung function with COPD and COPD-related phenotypes in a novel cohort of patients with severe to very severe COPD. We examined 315 cases of COPD and 330 Caucasian control smokers from Poland. We included three SNPs previously associated with COPD: rs7671167 (FAM13A), rs13180 (IREB2), and rs8034191 (CHRNA 3/5), and four SNPs associated with lung function in a genome-wide association study of general population samples: rs2070600 (AGER), rs11134242 (ADCY2), rs4316710 (THSD4), and rs17096090 (INTS12). We tested for associations with severe COPD and COPD-related phenotypes, including lung function, smoking behavior, and body mass index. Subjects with COPD were older (average age 62 versus 58 years, P < 0.01), with more pack-years of smoking (45 versus 33 pack-years, P < 0.01). CHRNA3/5 (odds ratio [OR], 1.89; 95% confidence interval [CI], 1.52.4; P = 7.4 × 10−7), IREB2 (OR, 0.69; 95% CI, 0.5–0.9; P = 3.4 × 10−3), and ADCY2 (OR, 1.35; 95% CI, 1.1–1.7; P = 0.01) demonstrated significant associations with COPD. FAM13A (OR, 0.8; 95% CI, 0.7–1.0; P = 0.11) approached statistical significance. FAM13A and ADCY2 also demonstrated a significant association with lung function. Thus, in severe to very severe COPD, we demonstrate a replication of association between two SNPs previously associated with COPD (CHRNA3/5 and IREB2), as well as an association with COPD of one locus initially associated with lung function (ADCY2). PMID:22461431

  16. Beyond the Dimer and Trimer: Tetraspiro[2.1.2(5) .1.2(9) .1.2(13) .1(3) ] hexadecane-1,3,5,7-tetraone-the Cyclic Tetramer of Carbonylcyclopropane.

    PubMed

    Sedenkova, Kseniya N; Averina, Elena B; Grishin, Yuri K; Andriasov, Kristian S; Stepanova, Svetlana A; Roznyatovsky, Vitaly A; Kutateladze, Andrei G; Rybakov, Victor B; Albov, Dmitry V; Kuznetsova, Tamara S; Zefirov, Nikolay S

    2016-03-14

    Tetraspiro[2.1.2(5) .1.2(9) .1.2(13) .1(3) ]hexadecane-1,3,5,7-tetraone 4, a unique tetraketone containing a cyclooctane core and four spiroannelated cyclopropane moieties, represents the previously unknown cyclotetramer of carbonylcyclopropane. For this purpose oxidation of the parent polyspirocyclic hydrocarbon was examined under various oxidative conditions, and the reactivity of oxidants towards methylene groups of the eight-membered cycle, activated by adjacent spirocyclopropane rings, was evaluated and contrasted. Whereas the treatment of tetraspirohexadecane with ozone resulted in monooxidation, its reaction with methyl(trifluoromethyl)dioxirane afforded the product of four-fold oxidation, triketoalcohol 10. Subsequent oxidation of the latter with Dess-Martin periodinane gave the target tetraketone 4. PMID:26762227

  17. Direct Observation of the 6S1 / 2 to 5D3 / 2 Electric Quadrupole Transition in Barium-138

    NASA Astrophysics Data System (ADS)

    Kleczewski, Adam; Hoffman, Matt; Magnuson, Eric; Blinov, Boris; Fortson, Norval

    2011-05-01

    The 6S1 / 2 to 5D3 / 2 electric quadrupole transition at 2051 nm in Ba+ plays an important role in a number of proposed experiments.,, We present the results of the first narrow laser spectroscopy performed on this transition. 2051 nm light is generated by a diode pumped solid state Tm,Ho:YLF laser. The laser is frequency stabilized to a high finesse cavity made from ultra-low expansion glass. In order to take advantage of higher performing optics and detectors available at shorter wavelengths, the 2051 nm light is frequency doubled using a periodically poled lithium niobate crystal inside a bow-tie enhancement cavity before being sent to the reference cavity. Using this laser system we observed Rabi oscillations on the 6S1 / 2 to 5D3 / 2 transition and demonstrated a laser-ion coherence time of 3 ms. This work is supported by NSF Grant PHY-0906494.

  18. Nonlinear optical properties of pulsed laser deposited Gd2O3 and Dy2O3 doped K0.5Na0.5NbO3 thin films

    NASA Astrophysics Data System (ADS)

    Peddigari, Mahesh; Pattipaka, Srinivas; Bharti, Gyan Prakash; Khare, Alika; Dobbidi, Pamu

    2016-08-01

    We report the structural and nonlinear optical properties of Gd2O3 and Dy2O3 doped (K0.5Na0.5)NbO3 (KNN) lead-free thin films fabricated by pulsed laser deposition technique. The crystal structure of the films was analyzed by using Rietveld method. The higher tetragonality and improved surface morphology was observed for the rare-earth oxide doped films. The change in crystal structure and tetragonality with these dopants was explained in terms of change in the internal vibration modes of NbO6 octahedra. The nonlinear optical properties of the films were measured by using single beam Z-scan technique with a continuous wave He-Ne laser (λ = 632.8 nm). All the films have shown a large third-order nonlinear susceptibility and observed to be enhanced for rare-earth doped KNN thin films (|χ(3)| = 2.69 × 10-3 esu). The maximum nonlinear refractive index, n2 = 2.02 × 10-5 cm2/W, and nonlinear absorption coefficient, β = 3.48 cm/W, were obtained for Gd2O3, and Dy2O3 doped films respectively. These results indicate that rare-earth doped KNN thin films are potential candidates for nonlinear photonic applications.

  19. High spin d5 complexes of tris(6-hydroxymethyl-2-pyridylmethyl)amine (H3L): hepta-coordinated [Mn(H3L)]Cl2 and linear trinuclear [Fe3L2](ClO4)3.

    PubMed

    Guisado-Barrios, Gregorio; Li, Yang; Slawin, Alexandra M Z; Richens, David T; Gass, Ian A; Murray, Paul R; Yellowlees, Lesley J; Brechin, Euan K

    2008-01-28

    Reaction of MnCl(2).4H(2)O with H(3)L (H(3)L = tris(6-hydroxymethyl-2-pyridylmethyl)amine) in methanol gives hepta-coordinated [Mn(H(3)L)]Cl(2) involving attachment of Mn(II) to all four nitrogens and three hydroxymethyl arms. Reaction of H(3)L with Fe(ClO(4))(2).6H(2)O in CH(3)CN in the presence of NaO(2)CC(6)H(5) in an attempt to make [Fe(III)OH(H(3)L)(O(2)CC(6)H(5))](ClO(4)), a putative model for soybean lipoxygenase-1, instead gave rise to the linear triiron(III) complex [Fe(3)L(2)](ClO(4))(3) with all three hydroxymethyl arms deprotonated and forming three alkoxide bridges between each Fe(III) centre. The central Fe(III) is hexa-coordinated to only the alkoxide bridges and flanked by two hepta-coordinated iron(III) centres analogous to the Mn(ii) complex. [Fe(3)L(2)](ClO(4))(3) exhibits two reversible 1e(-) reductions to mixed-valence [Fe(3)L(2)](2+) and [Fe(3)L(2)](+) forms. Structure data and magnetochemistry on [Fe(3)L(2)](ClO(4))(3) reveals the tightest Fe-O-Fe angle (87.4 degrees ) and shortest Fe...Fe distance (2.834 A) yet found for any weakly antiferromagnetically-coupled high spin alkoxide-bridged di- or triiron(iii) system and challenges current theories involved in correlating the extent/nature of magnetic interactions in such systems based on Fe-O(bridge) distances and Fe-O-Fe angles. The central hexa-alkoxide coordinated Fe(III) is novel and shows a remarkable resistance towards reduction to Fe(II). PMID:18185873

  20. Substitution effects on nonlinear optical activity of (X-methylphenyl)-5-nitro-6-amino-3-pyridinecarboxmide (X=2,3,4,5,6): A DFT approach

    NASA Astrophysics Data System (ADS)

    Premkumar, S.; Asath, R. Mohamed; Rekha, T. N.; Jawahar, A.; Mathavan, T.; Benial, A. Milton Franklin

    2016-05-01

    The substitution effects on the first order hyperpolarizability value of (X-methylphenyl)-5-nitro-6-amino-3-pyridinecarboxmide (X-MPNAPC),{X=2,3,4,5,6}molecule was calculated with the aid of density functional theory calculations. The optimized molecular structure of urea and (X-methylphenyl)-5-nitro-6-amino-3-pyridinecarboxmide (X-MPNAPC), {X=2,3,4,5,6} were predicted by the DFT/B3LYP method with cc-pVTZ basis set. The higher first order hyperpolarizability values were obtained for all molecules compared with the urea, which confirm that the higher nonlinear optical activity of the molecules. The frontier molecular orbitals (FMOs) analysis was carried out and their related molecular properties were calculated. The higher first order hyperpolarizability value was obtained for 4-MPNAPC molecule compared with other molecules, which indicates that the lower energy gap and extended π-conjugated bridge between the donor and acceptor group leads to the higher NLO activity of the molecule. Hence, this present investigation paves the way for designing the new organic NLO materials.

  1. Neutrino mass matrices from two zero 3 × 2 Yukawa textures and minimal d = 5 entries

    NASA Astrophysics Data System (ADS)

    Achelashvili, Avtandil; Tavartkiladze, Zurab

    2016-05-01

    Aiming to relate leptonic CP violating phase δ to the cosmological CP asymmetry, we study the extension of MSSM by two quasi-degenerate (strictly degenerate at tree level) right-handed neutrinos and consider all possible two texture zero 3 × 2 Yukawa matrices plus one ΔL = 2 dimension five (d = 5) operator contributing to the light neutrino mass matrix. We classify all experimentally viable mass matrices, leading to several predictions, and analytically derive predictive relations. We also relate the CP violating δ phase to the CP phase of the thermal leptogenesis.

  2. The metabolism of gamma-2,3,4,5,6-pentachlorocyclohex-1-ene and gamma-hexachlorocyclohexane in rats.

    PubMed

    Grover, P L; Sims, P

    1965-08-01

    1. After intraperitoneal administration, gamma-hexachlorocyclohexane (Gammexane) and gamma-2,3,4,5,6-pentachlorocyclohex-1-ene were converted by rats into 2,3,5- and 2,4,5-trichlorophenol, which were excreted as free phenols and as sulphuric acid and glucuronic acid conjugates. 2. Derivatives of 2,4,5-trichlorophenol and 2,4,5-trichlorophenyl glucosiduronic acid and 2,4-dichlorophenylmercapturic acid were isolated from the urine as metabolites of gamma-2,3,4,5,6-pentachlorocyclohex-1-ene. 3. The phenolic metabolites of gamma-hexachlorocyclohexane and gamma-2,3,4,5,6-pentachlorocyclohex-1-ene isolated from urine were similar to those of 1,2,4-trichlorobenzene, which indicates that the two latter compounds are intermediates in gamma-hexachlorocyclohexane metabolism in rats. PMID:4158352

  3. Superconducting Bi(1.5)Pb(0.5)Sr2Ca2Cu3O(x) ceramics by rapid melt quenching and glass crystallization

    NASA Technical Reports Server (NTRS)

    Bansal, Narottam P.

    1990-01-01

    The preparation of superconducting Bi(1.5)Pb(0.5)Sr2Ca2Cu3O(x) in the glassy state is described, and the results of a study of its crystallization kinetics are presented. The annealing parameters for transforming the glass into a superconductor containing a large fraction of the high-Tc phase were determined. It was found that prolonged annealing (longer than 10 days) in air at 840 C, followed by slow cooling, results in the Tc of 107.2 K and a sharp transition of 2 K.

  4. 3-[3-(3-florophenyl-2-propyn-1-ylthio)-1, 2, 5-thiadiazol-4-yl]-1, 2, 5, 6-tetrahydro-1- methylpyridine oxalate, a novel xanomeline derivative, improves neural cells proliferation and survival in adult mice

    PubMed Central

    Zhang, Xiaoliang; Gong, Qiang; Zhang, Shuang; Wang, Lin; Hu, Yinghe; Shen, Haiming; Dong, Suzhen

    2012-01-01

    The present study analyzed the influence of 3-[3-(3-florophenyl-2-propyn-1-ylthio)-1, 2, 5-thiadiazol-4-yl]-1, 2, 5, 6-tetrahydro-1-methylpyridine oxalate (EUK1001), a novel xanomeline derivative of the M1/M4 receptor agonist, on hippocampal neurogenesis in adult C57BL6 mice. Results showed that 15-day EUK1001 treatment via intraperitoneal injection promoted neural cell proliferation in the dentate gyrus, although cell differentiation did not change. The majority of bromodeoxyuridine-positive cells co-expressed the immature neuronal marker doublecortin. In addition, the level of neurogenesis in the subventricular zone was not altered. Brain-derived neurotrophic factor mRNA expression was up-regulated following EUK1001 treatment, but no change was observed in expression of camp-responsive element binding protein 1, paired box gene 6, vascular endothelial growth factor alpha, neurogenic differentiation factor 1, and wingless-related mouse mammary tumor virus integration site 3A mRNA. These experimental findings indicated that EUK1001 enhanced proliferation and survival of hippocampal cells, possibly by increasing brain-derived neurotrophic factor expression. PMID:25806054

  5. Influence of local structural disorders on spectroscopic properties of multi-component CaF2-Bi2O3-P2O5-B2O3 glass ceramics with Cr2O3 as nucleating agent

    NASA Astrophysics Data System (ADS)

    Suresh, S.; Narendrudu, T.; Yusub, S.; Suneel Kumar, A.; Ravi Kumar, V.; Veeraiah, N.; Krishna Rao, D.

    2016-01-01

    Multi-component CaF2-Bi2O3-P2O5-B2O3 glasses doped with different concentrations of Cr2O3 were crystallized through heat treatment. The prepared glass ceramic samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and differential thermal analysis (DTA). Spectroscopic studies viz., optical absorption, Fourier transform infrared (FTIR), Raman and electron paramagnetic resonance (EPR) were carried out. The XRD, SEM and DTA studies indicated that the samples contain different crystalline phases. Results of optical absorption and EPR studies pointed out the gradual conversion of chromium ions from Cr3 + state to Cr6 + state with an increase of Cr2O3 content from 0.1 to 0.5 mol%. The results of FTIR, Raman and EPR studies revealed that Cr6 + ions participate in the glass network in tetrahedral positions and seemed to increase the polymerization of the glass ceramics. The quantitative analysis of results of the spectroscopic studies further indicated that the glasses crystallized with low concentration of Cr2O3 are favourable for solid state laser devices.

  6. ClNO2 and nitrate (NO3-) formation via N2O5 uptake to particles: Derivation of N2O5 uptake coefficients from ambient datasets

    NASA Astrophysics Data System (ADS)

    Phillips, Gavin J.; Thieser, Jim; Tang, Ming J.; Sobanski, Nicolas; Fachinger, Johannes; Drewnick, Frank; Lelieveld, Jos; Crowley, John N.

    2015-04-01

    We present estimates of the uptake coefficient of N2O5, γ(N2O5), using ambient measurements of the trace gases N2O5 and ClNO2 and particle composition and surface area at the Kleiner Feldberg observatory, near Frankfurt, SW Germany, during the PARADE campaign (summer 2011). Three methods used to extract γ(N2O5) from the datasets were found to be in reasonable agreement, generating values between 0.001 and 0.4. γ(N2O5) displayed a significant dependence on relative humidity (RH), the largest values obtained, as expected, at high RH. No significant dependence of γ(N2O5) on particle organic content or sulphate-to-organic ratio was observed. The variability in γ(N2O5) is however large, indicating that humidity is not the sole factor determining the uptake coefficient. There is also an indication that the yield of ClNO2 with respect to N2O5 uptake is larger with lower concentrations of PM1 total organics. Our results will be compared to existing uptake coefficients from laboratory studies and those derived from field-observations.

  7. Development of new 5-(chromene-3-yl)methylene-2,4-thiazolidinediones as antimicrobial agents

    PubMed Central

    NASTASĂ, CRISTINA MARIANA; DUMA, MIHAELA; PÎRNĂU, ADRIAN; VLASE, LAURIAN; TIPERCIUC, BRÎNDUŞA; ONIGA, OVIDIU

    2016-01-01

    Background and aims In the context of the increasing phenomenon of microbial resistance to usual drugs, the development of new treatment strategies and new therapeutic protocols is a constant need. Thiazolidinedione and chromone represent two important scaffolds in medicinal chemistry due to their large pharmacological applicability. Methods We synthesized a new 5-(chromene-3-yl)methylene-2,4-thiazolidinedione starting from 6,8-dichloro-4-oxo-4H-chromene-3-carbaldehyde. Then, by treating with different α-bromoalkylarylketones, we obtained N-substituted derivatives. All new compounds were investigated for their antimicrobial potential, using the diffusion method, against Listeria monocytogenes ATCC 13932, Staphylococcus aureus ATCC 49444, Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 14028 and Candida albicans ATCC 10231. Three concentrations, 10 mg/ml, 5 mg/ml and 1 mg/ml of compounds were used. The results were evaluated by the measurement of the inhibition zone diameters and compared to those of gentamicin and fluconazole respectively, as reference drugs. Results All new synthesized compounds were characterized using physico-chemical and spectrometric methods. They displayed modest to good antimicrobial activity. New molecules 8, 9 and 10 may represent promising candidates, showing zone inhibition diameters superior to those of reference drugs. Conclusions This work presents chemical synthesis, characterization and investigation of the antibacterial and antifungal potential of 5-(chromene-3-yl)methylene-2,4-thiazolidinedione derivatives, which may be worthy of future research for designing new chemical entities. PMID:27004035

  8. Enhancement of CO2 Adsorption and Catalytic Properties by Fe-Doping of [Ga2(OH)2(L)] (H4L = Biphenyl-3,3′,5,5′-tetracarboxylic Acid), MFM-300(Ga2)

    PubMed Central

    2016-01-01

    Metal–organic frameworks (MOFs) are usually synthesized using a single type of metal ion, and MOFs containing mixtures of different metal ions are of great interest and represent a methodology to enhance and tune materials properties. We report the synthesis of [Ga2(OH)2(L)] (H4L = biphenyl-3,3′,5,5′-tetracarboxylic acid), designated as MFM-300(Ga2), (MFM = Manchester Framework Material replacing NOTT designation), by solvothermal reaction of Ga(NO3)3 and H4L in a mixture of DMF, THF, and water containing HCl for 3 days. MFM-300(Ga2) crystallizes in the tetragonal space group I4122, a = b = 15.0174(7) Å and c = 11.9111(11) Å and is isostructural with the Al(III) analogue MFM-300(Al2) with pores decorated with −OH groups bridging Ga(III) centers. The isostructural Fe-doped material [Ga1.87Fe0.13(OH)2(L)], MFM-300(Ga1.87Fe0.13), can be prepared under similar conditions to MFM-300(Ga2) via reaction of a homogeneous mixture of Fe(NO3)3 and Ga(NO3)3 with biphenyl-3,3′,5,5′-tetracarboxylic acid. An Fe(III)-based material [Fe3O1.5(OH)(HL)(L)0.5(H2O)3.5], MFM-310(Fe), was synthesized with Fe(NO3)3 and the same ligand via hydrothermal methods. [MFM-310(Fe)] crystallizes in the orthorhombic space group Pmn21 with a = 10.560(4) Å, b = 19.451(8) Å, and c = 11.773(5) Å and incorporates μ3-oxo-centered trinuclear iron cluster nodes connected by ligands to give a 3D nonporous framework that has a different structure to the MFM-300 series. Thus, Fe-doping can be used to monitor the effects of the heteroatom center within a parent Ga(III) framework without the requirement of synthesizing the isostructural Fe(III) analogue [Fe2(OH)2(L)], MFM-300(Fe2), which we have thus far been unable to prepare. Fe-doping of MFM-300(Ga2) affords positive effects on gas adsorption capacities, particularly for CO2 adsorption, whereby MFM-300(Ga1.87Fe0.13) shows a 49% enhancement of CO2 adsorption capacity in comparison to the homometallic parent material. We thus report herein the

  9. 3-(2,4-Dichloro-benzyl-idene)-1,5-dioxa-spiro-[5.5]undecane-2,4-dione.

    PubMed

    Zeng, Wu-Lan

    2011-06-01

    In the title mol-ecule, C(16)H(14)Cl(2)O(4), the 1,3-dioxane and cyclo-hexane rings exhibit distorted boat and chair conformations, respectively. In the crystal, a pair of weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into an inversion dimer. PMID:21754756

  10. The crystal structure of 4′-{4-[(2,2,5,5-tetra­methyl-N-oxyl-3-pyrrolin-3-yl)ethyn­yl]phen­yl}-2,2′:6′,2′′-terpyridine

    PubMed Central

    Meyer, Andreas; Wiecek, Jennifer; Schnakenburg, Gregor; Schiemann, Olav

    2015-01-01

    The terpyridine group of the title compound, C31H27N4O, assumes an all-transoid conformation and is essentially planar with the dihedral angles between the mean planes of the central pyridine and the two outer rings amounting to 3.87 (5) and 1.98 (5)°. The pyrroline-N-oxyl group commonly seen in such nitroxyls is found in the title structure and the mean plane of the pyrroline ring subtends a dihedral angle of 88.44 (7)° to the mean plane of the central pyridine ring. The intra­molecular separation between the nitrogen atom of the central pyridine unit of the terpyridine group and the nitroxyl group is 14.120 (2) Å. In the crystal, the mol­ecules are arranged in layers stacked along [001]. Slipped face-to-face π–π inter­actions between the pyridine rings are observed along this direction with the shortest centroid–centroid distances amounting to 3.700 (1) and 3.781 (1) Å. Furthermore, edge-on C—H⋯π inter­actions between the phenyl­ene rings of neighbouring mol­ecules are observed along this direction. A two-dimensional C—H⋯O hydrogen-bonded network is formed within the (010) plane. The shortest O⋯O separation between neighbouring mol­ecules is 5.412 (3) Å. PMID:26279889

  11. Synthesis, characterization, and crystal structure of 5,5″-Difluoro-1 H,1″ H-[3,3':3',3″-terindol]-2'(1' H)-one

    NASA Astrophysics Data System (ADS)

    Sharma, Sakshi; Banerjee, Bubun; Brahmachari, Goutam; Kant, Rajni; Gupta, Vivek K.

    2016-03-01

    The new indole derivative, 5,5''-Difluoro-1 H,1'' H-[3,3':3',3''-terindol]-2'(1' H)-one C24H15F2N3O, is synthesized in 87% yield, and its crystal structure is determined by X-ray structure analysis. The crystals are monoclinic, sp. gr. P21/ n, a = 15.4563(7), b = 10.8340(6), c = 16.4718(6) Å, β = 102.403(4)°, Z = 4. Bicyclic indole moieties form dihedral angle of 61.92(5)° with each other; the oxindole ring is twisted with respect to them at angles of 85.70(5)° and 75.62(5)°. The crystal structure is stabilized by N-H···O and C-H···O hydrogen bonds involving both the DMSO solvent molecules. In addition, one C-H···π interaction is observed.

  12. Molecular docking studies of (X-methylphenyl)-5-nitro-6-amino-3-pyridinecarboxmide (X=2,3,4,5,6) as potential inhibitors for Alzheimer's disease

    NASA Astrophysics Data System (ADS)

    Premkumar, S.; Asath, R. Mohamed; Rekha, T. N.; Jawahar, A.; Mathavan, T.; Benial, A. Milton Franklin

    2016-05-01

    An insilico and density functional theory (DFT) calculations were carried out for (X-methylphenyl)-5-nitro-6-amino-3-pyridinecarboxmide (X-MPNAPC),{X=2,3,4,5,6} to evaluate the potential inhibitors for Alzheimer's disease. The molecular structure of 2-MPNAPC, 3-MPNAPC, 4-MPNAPC, 5-MPNAPC and 6-MPNAPC molecules was optimized by the DFT/B3LYP method with cc-pVTZ basis set using the Gaussian 09 program. The inhibitory nature of the molecules against enzyme acetylcholinesterase (AChE) catalyzes was evaluated by molecular docking studies. The molecular docking parameters such as binding energy, inhibition constant and intermolecular energy were calculated by the AutoDock 4.0 software. The higher binding energy, intermolecular energy and lower inhibition constant values suggested that the 2-MPNAPC molecule has higher inhibitory nature against the AChE catalyzes, which confirm that the 2-MPNAPC molecule is a potential inhibitor for the Alzheimer's disease. The molecular reactivity was also studied by the frontier molecular orbitals analysis.

  13. Catalytic performance of V2O5-MoO3/γ-Al2O3 catalysts for partial oxidation of n-hexane1

    NASA Astrophysics Data System (ADS)

    Mahmoudian, R.; Khodadadi, Z.; Mahdavi, Vahid; Salehi, Mohammed

    2016-01-01

    In the current study, a series of V2O5-MoO3 catalyst supported on γ-Al2O3 with various V2O5 and MoO3 loadings was prepared by wet impregnation technique. The characterization of prepared catalysts includes BET surface area, powder X-ray diffraction (XRD), and oxygen chemisorptions. The partial oxidation of n-hexane by air over V2O5-MoO3/γ-Al2O3 catalysts was carried out under flow condition in a fixed bed glass reactor. The effect of V2O5 loading, temperature, MoO3 loading, and n-hexane LHSV on the n-hexane conversion and the product selectivity were investigated. The partial oxygenated products of n-hexane oxidation were ethanol, acetic anhydride, acetic acid, and acetaldehyde. The 10% V2O5-1%MoO3/γ-Al2O3 was found in most active and selective catalyst during partial oxidation of n-hexane. The results indicated that by increasing the temperature, the n-hexane conversion increases as well, although the selectivity of the products passes through a maximum by increasing the temperature.

  14. Compressibility and phase transitions in Bi(1.6)Pb(0.4)Sr2Ca(2.5)Cu(3.5)O(x) polycrystalline ceramic

    NASA Astrophysics Data System (ADS)

    Balankina, E. S.

    1991-11-01

    Ultrasonic resonance measurements of the bulk modulus of elasticity were conducted for disk (15 mm in diameter, 3 mm thick) specimens of polycrystalline Bi(1.6)Pb(0.4)Sr2Ca(2.5)Cu(3.5)O(x) ceramic in the temperature range 85-300 K. The bulk modulus of elasticity is found to increase monotonically as the temperature decreases and exibits well defined anomalies in the form of discontinuities and slope changes at 102, 120, 200, and 255 K. The possible mechanisms of the observed anomalies are discussed.

  15. The 2′-5′-Oligoadenylate Synthetase 3 Enzyme Potently Synthesizes the 2′-5′-Oligoadenylates Required for RNase L Activation

    PubMed Central

    Ibsen, Mikkel Søes; Gad, Hans Henrik; Thavachelvam, Karthiga; Boesen, Thomas; Desprès, Philippe

    2014-01-01

    ABSTRACT The members of the oligoadenylate synthetase (OAS) family of proteins are antiviral restriction factors that target a wide range of RNA and DNA viruses. They function as intracellular double-stranded RNA (dsRNA) sensors that, upon binding to dsRNA, undergo a conformational change and are activated to synthesize 2′-5′-linked oligoadenylates (2-5As). 2-5As of sufficient length act as second messengers to activate RNase L and thereby restrict viral replication. We expressed human OAS3 using the baculovirus system and purified it to homogeneity. We show that recombinant OAS3 is activated at a substantially lower concentration of dsRNA than OAS1, making it a potent in vivo sensor of dsRNA. Moreover, we find that OAS3 synthesizes considerably longer 2-5As than previously reported, and that OAS3 can activate RNase L intracellularly. The combined high affinity for dsRNA and the capability to produce 2-5As of sufficient length to activate RNase L suggests that OAS3 is a potent activator of RNase L. In addition, we provide experimental evidence to support one active site of OAS3 located in the C-terminal OAS domain and generate a low-resolution structure of OAS3 using SAXS. IMPORTANCE We are the first to purify the OAS3 enzyme to homogeneity, which allowed us to characterize the mechanism utilized by OAS3 and identify the active site. We provide compelling evidence that OAS3 can produce 2′-5′-oligoadenylates of sufficient length to activate RNase L. This is contrary to what is described in the current literature but agrees with recent in vivo data showing that OAS3 harbors an antiviral activity requiring RNase L. Thus, our work redefines our understanding of the biological role of OAS3. Furthermore, we used a combination of mutagenesis and small-angle X-ray scattering to describe the active site and low-resolution structure of OAS3. PMID:25275129

  16. 3-(2-Amino-5-nitro­anilino)-5,5-dimethyl­cyclo­hex-2-en-1-one 0.25-hydrate

    PubMed Central

    Mehdi, Sayed Hasan; Hashim, Rokiah; Ghalib, Raza Murad; Goh, Jia Hao; Fun, Hoong-Kun

    2010-01-01

    The asymmetric unit of the title compound, C14H17N3O3·0.25H2O, comprises two independent organic mol­ecules and a water mol­ecule lying on a crystallographic twofold rotation axis with 50% site occupancy. In both independent mol­ecules, the cyclo­hexene rings adopt envelope conformations but superposition of the two molecules shows that the flap atoms point in opposite directions. In the crystal, N—H⋯O and C—H⋯O hydrogen bonds inter­connect adjacent mol­ecules into a three-dimensional network. Weak inter­molecular π–π aromatic stacking inter­actions [centroid–centroid distances = 3.4985 (9) and 3.6630 (9) Å] are also observed. PMID:21588741

  17. [UO2(NH3)5]Br2·NH3: synthesis, crystal structure, and speciation in liquid ammonia solution by first-principles molecular dynamics simulations.

    PubMed

    Woidy, Patrick; Bühl, Michael; Kraus, Florian

    2015-04-28

    Pentaammine dioxido uranium(VI) dibromide ammonia (1/1), [UO2(NH3)5]Br2·NH3, was synthesized in the form of yellow crystals by the reaction of uranyl bromide, UO2Br2, with dry liquid ammonia. The compound crystallizes orthorhombic in space group Cmcm and is isotypic to [UO2(NH3)5]Cl2·NH3 with a = 13.2499(2), b = 10.5536(1), c = 8.9126(1) Å, V = 1246.29(3) Å(3) and Z = 4 at 123 K. The UO2(2+) cation is coordinated by five ammine ligands and the coordination polyhedron can be best described as pentagonal bipyramid. Car-Parrinello molecular dynamics simulations are reported for [UO2(NH3)5](2+) in the gas phase and in liquid NH3 solution (using the BLYP density functional). According to free-energy simulations, solvation by ammonia has only a small effect on the uranyl-NH3 bond strength. PMID:25797497

  18. Spectroscopic studies and structure of 3-methoxy-2 -[(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde

    SciTech Connect

    Oezay, H.; Yildiz, M.; Uenver, H.; Durlu, T. N.

    2013-01-15

    The compound called 3-methoxy-2- [(2,4,4,6,6-pentachloro-1,3,5,2{lambda}{sup 5},4{lambda}{sup 5},6{lambda}{sup 5}-triazatriphosphin-2-yl)oxy] benzaldehyde has been synthesized from the reaction of 2-hydroxy-3-methoxybenzaldehyde with hexachlorocyclotriphosphazene. It has been characterized by elemental analysis, MS, IR, {sup 1}H NMR, {sup 13}C NMR, {sup 31}P NMR and UV-visible spectroscopic techniques. The structure of the title compound has been determind by X-ray analysis. Crystals are orthorhombic, space group P2{sub 1}2{sub 1}2{sub 1}, Z = 4, a = 7.705(1), b = 12.624(1), c = 17.825(2) A, R{sub 1} = 0.0390 and wR{sub 2} = 0.1074 [I > 2{sigma}(I)], respectively.

  19. Multiple bonds between transition metals and main-group elements. 73. Synthetic routes to rhenium(V) alkyl and rhenium(VII) alkylidyne complexes. X-ray crystal structures of (. eta. sup 5 -C sub 5 Me sub 5 )Re( double bond O)(CH sub 3 )(CH sub 2 C(CH sub 3 ) sub 3 ) and (. eta. sup 5 -C sub 5 Me sub 5 )(Br) sub 3 Re triple bond CC(CH sub 3 ) sub 3

    SciTech Connect

    Herrmann, W.A.; Felixberger, J.K.; Anwander, R.; Herdtweck, E.; Kiprof, P.; Riede, J. )

    1990-05-01

    Dialkyloxo({eta}{sup 5}pentamethylcyclopentadienyl)rhenium(V) complexes ({eta}{sup 5}-C{sub 5}Me{sub 5})Re({double bond}O)(CH{sub 3})R{prime}(R{prime} = C{sub 2}H{sub 5}, CH{sub 2}Si(CH{sub 3}){sub 3}, CH{sub 2}C(CH{sub 3}){sub 3}), 1c-e, have become accessible through alkylation of ({eta}{sup 5}-C{sub 5}Me{sub 5})Re({double bond}O)(Cl)(CH{sub 3}) (7) with R{prime}MgCl. 1c-e are the first rhenium complexes containing different alkyl ligands. The neopentyl derivative 1e (R{prime} = CH{sub 2}C(CH{sub 3}){sub 3}) crystallizes in the orthorhombic space group Pbca with a = 960.7 (2), b = 2.844.5 (4), c = 1,260.7 (2) pm, and Z = 8. The X-ray crystal structure was refined to R{sub W} = 3.9%. The chiral molecule shows a distorted tetrahedral geometry around the rhenium center. The tribromide 3b has been structurally characterized. Brown crystals of 3b belong to space group P2{sub 1}/c with unit cell dimensions a = 1,311.5 (2), b = 723.0 (1), c = 1,901.6 (2) pm, {beta} = 92.68 (1){degree}, and Z = 4. The structure exhibits a four-legged piano stool geometry with no trans influence of the neopentylidyne ligand to the bromine atom.

  20. Electron Transport Properties in HSi(OC2H5)3 Vapor

    NASA Astrophysics Data System (ADS)

    Yoshida, Kosaku; Sato, Ran; Yokota, Takuya; Kishimoto, Yasutaka; Date, Hiroyuki

    2011-12-01

    The electron swarm parameters in HSi(OC2H5)3 (triethoxysilane, TRIES) vapor have been investigated for relatively wide ranges of reduced electric field (E/N). Based on the arrival-time spectra (ATS) method for electrons using a double-shutter drift tube, the drift velocity and the longitudinal diffusion coefficient were measured for the E/N=20-5000 Td, and the ionization coefficient was obtained for E/N=300-5000 Td. The results were compared with those for SiH4 and Si(OC2H5)4 (tetraethoxysilane, TEOS), to show characteristics similar to the parameters in TEOS. We also determined the electron collision cross sections for TRIES by means of the Boltzmann equation analysis.

  1. Synthesis and characterisation of selected group 14 derivatives of the 2,5-(CF3)2C6H3 (Ar) ligand.

    PubMed

    Coffer, Philippa K; Dillon, Keith B; Howard, Judith A K; Yufit, Dmitry S; Zorina, Natalia V

    2012-04-21

    Selected group 14 tetrahalides EX(4) (E = Si, Ge or Sn; X = Cl or Br) have been reacted in various molar ratios with ArLi, where Ar = 2,5-(CF(3))(2)C(6)H(3). The compounds Ar(2)SiCl(2)1, Ar(3)SiF 3, Ar(2)Si(OH)(2)4, Ar(2)GeCl(2)7, Ar(2)Ge(Br)Ge(Br)Ar(2)8, Ar(3)SnCl 10, Ar(4)Sn 11 and Ar(3)SnBr 12 have been isolated, and characterised by single-crystal X-ray diffraction, elemental analysis and (19)F solution-state NMR spectroscopy. PMID:22354314

  2. Nitrogen Oxides in the Nocturnal Boundary Layer: Simultaneous In-situ Measurements of NO3, N2O5, NO2, NO and O3

    NASA Astrophysics Data System (ADS)

    Brown, S. S.; Stark, H.; Ryerson, T. B.; Williams, E. J.; Nicks, D. K.; Trainer, M.; Fehsenfeld, F. C.; Ravishankara, A. R.

    2002-12-01

    We report the first simultaneous, in-situ observation of a suite of compounds important in nocturnal nitrogen oxide chemistry. Measurements took place at a ground site near Boulder, CO, during the fall of 2001. Chemical measurements included NO3, N2O5, NO, NO2 and O3; meteorological data were also available. The concentrations of NO3 and N2O5 showed large dynamic ranges that were consistent with variations in N2O5 and NO, and with shifts in meteorological conditions at this site. The observed ratio of N2O5 to NO3 agreed with the ratio calculated from the measured NO2 concentration and the temperature-dependent equilibrium constant. In addition, NO3 and N2O5 showed large short-term variability that may indicate inhomogeneously mixed source and sink compounds and/or deposition at this ground-based measurement site. Finally, N2O5 reached a peak concentration of nearly 3 ppbv under polluted conditions and accounted for an appreciable fraction of the total concentration of measured nitrogen oxide species.

  3. The Rest-Frame Optical Luminosity Functions of Galaxies at 2<=z<=3.5

    NASA Astrophysics Data System (ADS)

    Marchesini, D.; van Dokkum, P.; Quadri, R.; Rudnick, G.; Franx, M.; Lira, P.; Wuyts, S.; Gawiser, E.; Christlein, D.; Toft, S.

    2007-02-01

    We present the rest-frame optical (B, V, and R band) luminosity functions (LFs) of galaxies at 2<=z<=3.5, measured from a K-selected sample constructed from the deep NIR MUSYC, the ultradeep FIRES, and the GOODS-CDFS. This sample is unique for its combination of area and range of luminosities. The faint-end slopes of the LFs at z>2 are consistent with those at z~0. The characteristic magnitudes are significantly brighter than the local values (e.g., ~1.2 mag in the R band), while the measured values for Φ* are typically ~5 times smaller. The B-band luminosity density at z~2.3 is similar to the local value, and in the R band it is ~2 times smaller than the local value. We present the LF of distant red galaxies (DRGs), which we compare to that of non-DRGs. While DRGs and non-DRGs are characterized by similar LFs at the bright end, the faint-end slope of the non-DRG LF is much steeper than that of DRGs. The contribution of DRGs to the global densities down to the faintest probed luminosities is 14%-25% in number and 22%-33% in luminosity. From the derived rest-frame U-V colors and stellar population synthesis models, we estimate the mass-to-light ratios (M/L) of the different subsamples. The M/L ratios of DRGs are ~5 times higher (in the R and V bands) than those of non-DRGs. The global stellar mass density at 2<=z<=3.5 appears to be dominated by DRGs, whose contribution is of order ~60%-80% of the global value. Qualitatively similar results are obtained when the population is split by rest-frame U-V color instead of observed J-K color. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS5-26555. Also based on observations collected at the European Southern Observatories on Paranal, Chile as part of the ESO program 164.O-0612.

  4. Ethyl 4-(1,3-benzodioxol-5-yl)-6-methyl-2-sulfanylidene-1,2,3,4-tetra­hydro­pyrimidine-5-carboxyl­ate

    PubMed Central

    Nayak, Susanta K.; Venugopala, K. N.; Govender, Thavendran; Kruger, Hendrik G.; Maguire, Glenn E. M.; Row, Tayur N. Guru

    2011-01-01

    In the title compound, C15H16N2O4S, the dihedral angles between the planes of the benzodioxole and ester groups and the plane of the six-membered tetra­hydro­pyrimidine ring are 89.5 (1) and 20.2 (1)°, respectively. Inter­molecular N—H⋯S hydrogen bonds assemble the mol­ecules into dimers, which are further connected via N—H⋯O inter­actions into chains parallel to [010]. Weak C—H⋯S and C—H⋯π inter­actions enhance the stability of the crystal structure. PMID:22220078

  5. (2-Arylethenyl)-1,3,5-triazin-2-amines as a novel histamine H4 receptor ligands.

    PubMed

    Kamińska, Katarzyna; Ziemba, Julia; Ner, Joanna; Schwed, Johannes Stephan; Łażewska, Dorota; Więcek, Małgorzata; Karcz, Tadeusz; Olejarz, Agnieszka; Latacz, Gniewomir; Kuder, Kamil; Kottke, Tim; Zygmunt, Małgorzata; Sapa, Jacek; Karolak-Wojciechowska, Janina; Stark, Holger; Kieć-Kononowicz, Katarzyna

    2015-10-20

    Within the constantly growing number of histamine H4 (H4R) receptor ligands there is a large group of azine derivatives. A series of novel compounds in the group of 4-methylpiperazine-1,3,5-triazine-2-amines were designed and obtained. Considered structures were modified at the triazine 6-position by introduction of variously substituted arylethenyl moieties. Their affinities to histamine H4 receptors were evaluated in radioligand binding assays with use of Sf9 cells, transiently expressing human H4R. Pharmacological studies results allowed to identify 4-[(E)-2-(3-chlorophenyl)ethenyl]-6-(4-methylpiperazin-1-yl)-1,3,5-triazin-2-amine (Ki = 253 nM) as the most potent compound in the present series. PMID:26360048

  6. Study of the gas inclusions in Al 2O 3/Y 3Al 5O 12 and Al 2O 3/Y 3Al 5O 12/ZrO 2 eutectic fibers grown by laser floating zone

    NASA Astrophysics Data System (ADS)

    Oliete, Patricia B.; Peña, José I.

    2007-06-01

    Gas bubbles appear in some metal oxides grown by directional solidification in air when high growth rates are used. The incorporation of bubbles in Al 2O 3-YAG (AY) and Al 2O 3-YAG-ZrO 2 (AYZ) eutectic crystals grown using the laser floating zone method was investigated. The effect of different growth experimental parameters was considered. Growth rate, rod diameter and growth atmosphere were found to be determinant in order to reduce the gas inclusions. The optimization of the growth parameters allowed to grow AY and AYZ eutectic crystals free of bubbles at very high growth rates at which interphase spacings smaller than 300 nm were obtained.

  7. 5-Phenyl-3-(2-thien­yl)-1,2,4-triazolo[3,4-a]isoquinoline

    PubMed Central

    Khan, F. Nawaz; Manivel, P.; Prabakaran, K.; Hathwar, Venkatesha R.; Ng, Seik Weng

    2010-01-01

    In the title mol­ecule, C20H13N3S, the triazoloisoquinoline ring system is approximately planar, with an r.m.s. deviation of 0.045 Å and a maximum deviation of 0.090 (2) Å from the mean plane for the triazole ring C atom which is bonded to the thio­phene ring. The phenyl ring is twisted by 52.0 (1)° with respect to the mean plane of the triazoloisoquinoline ring system. The thio­phene ring is rotationally disordered by approximately 180° over two sites, the ratio of refined occupancies being 0.73 (1):0.27 (1). PMID:21579895

  8. Electronic Raman Scattering Investagation of Underdoped YBa_2Cu_3O_6.5

    NASA Astrophysics Data System (ADS)

    Chen, X. K.; Naeini, J. G.; Hewitt, K. C.; Irwin, J. C.; Liang, R.; Hardy, W. N.

    1997-03-01

    The Raman spectra of an underdoped YBa_2Cu_3O_6.5 single crystal (T_c=61K) have been measured in the XX(A_1g+B_1g), X^'X^'(A_1g+B_2g), XY(B_2g), and X^'Y^'(B_1g) scattering geometries at temperatures above and below T_c. When the sample temperature is decreased below T_c, a superconductivity-induced redistribution of the electronic continua is observed, similar to that observed in optimally doped high-Tc cuprates. The linear frequency-dependence observed in the low-energy XY and X^'X^' continuum indicates the existence of line nodes in the superconducting gap near the (± 1,± 1) directions in k-space, consistent with d_x^2-y^2 symmetry. The intensity ratio I(B_2g)/I(B_1g) is found to be considerably greater than that measured in optimally doped YBa_2Cu_3Ox crystals, which is interpreted as a consequence of the opening of a pseudo gap in the normal state of the underdoped samples.

  9. 3-Chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) and mutagenic activity in Massachusetts drinking water.

    PubMed

    Wright, J Michael; Schwartz, Joel; Vartiainen, Terttu; Mäki-Paakkanen, Jorma; Altshul, Larisa; Harrington, Joseph J; Dockery, Douglas W

    2002-02-01

    There is limited information on the prevalence of the potent mutagen 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) in U.S. water supplies. We measured MX concentrations and mutagenic activity in tap water samples from 36 surface water systems throughout Massachusetts. We found MX levels much higher (up to 80 ng/L) than previously reported in the United States. We also evaluated the role of water treatment on mutagenic activity and disinfection by-product formation. After adjusting for other covariates, chloramination and filtration were the most important treatment options for reducing mutagenic activity and disinfection by-product formation. Multiple chlorine application (before and after filtration) was associated with increased mutagenicity. Chlorine dose, pH, and total organic carbon were also associated with mutagenicity, MX, and total trihalomethane (TTHM) concentration. Seasonal variation was evident for MX and mutagenic activity, with higher levels occurring in the spring compared to the fall. In contrast, TTHM concentrations were greater in the fall. PMID:11836144

  10. Crystallographic Texture and Orientation Variants in Al2O3-Y3Al5O12 Directionally Solidified Eutectic Crystals

    NASA Technical Reports Server (NTRS)

    Frazer, Colleen S.; Dickey, Elizabeth C.; Sayir, Ali; Farmer, Serene (Technical Monitor)

    2001-01-01

    Eutectic rods of Al2O3 and Y3Al5O12 were grown by a laser-heated float zone method, and their microstructure and crystallographic texture were studied by scanning electron microscopy, electron backscattered diffraction and x-ray diffraction. The composites were found to be highly textured with two twin-related crystallographic orientation relationships between the phases. Electron backscattered diffraction was employed to determine the spatial distribution of the orientational variants within the samples and to define the crystallographic orientation of various microstructural features.

  11. Magnetic properties of synthetic Ni3Si2O5(OH)4 nanotubes

    NASA Astrophysics Data System (ADS)

    Krasilin, Andrei A.; Semenova, Anna S.; Kellerman, Dina G.; Nevedomsky, Vladimir N.; Gusarov, Victor V.

    2016-02-01

    The present study focuses on the magnetic properties of the nanotubular Ni3Si2O5(OH)4 pecoraite, the structural analogue of chrysotile, obtained by hydrothermal synthesis. The cell parameters of the material, determined by X-ray diffraction, are a=0.528(1) \\text{nm} , b=0.917(0) \\text{nm} , c=1.460(1) \\text{nm} and β=92.4(7)\\circ . The element analysis revealed the decrease of the Ni:Si ratio after hydrothermal treatment. The synthesized nanotubes have bigger outer and inner diameters in comparison to chrysotile. Using a vibration sample magnetometer, we determined the temperature of the ferromagnetic transition (23.7 K), μ{eff} of the \\text{Ni}2+ ion in pecoraite (3.48 μ \\text{B}) and the blocking temperature (18 K).

  12. 2-{4-[(1,3-Benzodioxol-5-yl)meth-yl]piperazin-1-yl}pyrimidine.

    PubMed

    Wu, Chunli; Li, Jieming; Wei, Huijie; Hang, Ye; Jiang, Yueming

    2013-01-01

    In the title compound, C16H18N4O2, known also as peribedil, the dihedral angle between the mean planes of the pyrimidine and benzene rings is 56.5 (8)°. The 1,3-dioxole fragment adopts an envelope conformation with the methyl-ene C atom forming the flap; this atom deviates by 0.232 (3) Å from the plane defined by the remaining atoms of the 1,3-benzodioxole unit. In the crystal, C-H⋯π inter-actions between c-glide-related mol-ecules arrange them into columns extending along the c-axis direction. The columns related by a unit translation along the b axis are packed into (100) layers via another C-H⋯π inter-action involving the pyrimidine ring as an acceptor. PMID:24046690

  13. High Magnetic Field Properties of Ce2Rh3Ge5

    NASA Astrophysics Data System (ADS)

    Wartenbe, Mark

    2015-03-01

    The competition between localized and delocalized f electrons in heavy fermion materials produces a wide variety of interesting physical phenomena. Among these compounds is Ce2Rh3Ge5. This heavy-fermion system undergoes an antiferromagnetic transition below 4K and exhibits an angle dependent magnetic phase transition around 25 tesla. In addition, RF conductivity measurements in pulsed field (65T) have revealed quantum oscillations. Temperature dependence at fixed angle indicates relatively heavy effective masses of values ranging from around 3me on up to 10me. This indicates that the narrow f-electron density of states is partially hybridized close to the Fermi energy, but also places strict cryogenic constraints upon the measurement (3Helium temperatures are required). Fermi surface calculations have produced complex figures which lend validation to such rich behavior. Ryan Baumbach, Andrew Gallagher, Eric Bauer, Ross McDonald, Kuan-Wen Chen,David Graf.

  14. Structural analysis of three methyl N-phosphorylated 5,6-dihydroxy-2-azabicyclo[2.2.1]heptane-3-carboxylates

    NASA Astrophysics Data System (ADS)

    Sousa, Carlos A. D.; Vale, M. Luísa C.; Rodríguez-Borges, José E.; Garcia-Mera, Xerardo

    2012-01-01

    Both exo and endo isomers of (±)-methyl N-diphenylphosphoryl-2-azabicyclo[2.2.1]hept-5-ene-3-carboxylate and (±)-methyl N-diphenylphosphoryloxy-2-azabicyclo[2.2.1]hept-5-ene-3-carboxylate were dihydroxylated with OsO 4. The unexpected formation of (±)-methyl 5,6-dihydroxy -N-diphenylphosphoryl-2-azabicyclo[2.2.1]heptane-3- endo-carboxylate from (±)-methyl N-diphenylphosphoryloxy-2-azabicyclo[2.2.1]hept-5-ene-3- endo-carboxylate is discussed based on NMR analyses and experimental observations. The two N-diphenylphosphoryl dihydroxybicycles are analyzed in terms of their crystalline structure by X-ray crystallography.

  15. 40 CFR 721.5283 - Cobaltate (5-), bis[4-[[6-[(4-amino-6-chloro-1,3,5-triazin-2-yl)amio]-1-hydroxy-3-sulfo-2...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Cobaltate (5-), bis -1-hydroxy-3-sulfo... Substances § 721.5283 Cobaltate (5-), bis -1-hydroxy-3-sulfo-2-naphthalenyl]azo]-3-hydroxy-7-nitro-1... chemical substance identified as cobaltate (5-), bis...

  16. 40 CFR 721.5283 - Cobaltate (5-), bis[4-[[6-[(4-amino-6-chloro-1,3,5-triazin-2-yl)amio]-1-hydroxy-3-sulfo-2...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Cobaltate (5-), bis -1-hydroxy-3-sulfo... Substances § 721.5283 Cobaltate (5-), bis -1-hydroxy-3-sulfo-2-naphthalenyl]azo]-3-hydroxy-7-nitro-1... chemical substance identified as cobaltate (5-), bis...

  17. Magnetic, transport and thermodynamic properties of Ce5Ni2Si3 compound

    NASA Astrophysics Data System (ADS)

    Kowalczyk, A.; Falkowski, M.; Toliński, T.

    2012-10-01

    The magnetization M(T,H), specific heat Cp(T,H), electrical resistivity ρ(T), magnetoresistance MR(T,H), thermal conductivity κ(T) and thermopower S(T) measurements were performed on the antiferromagnetic compound Ce5Ni2Si3 with the Néel temperature TN = 5.7 K. The estimated effective moment μeff is close to the free ion value of Ce in its trivalent state. The negative sign of the paramagnetic Curie temperature θp indicate the antiferromagnetic nature of the magnetic ordering. The variation of magnetic resistivity ρmag with temperature in Ce5Ni2Si3 can be explained by a competition of the crystal electric field (CEF) splitting, the Kondo effect and the magnetic order. Based on the thermopower and employing a simple single-ion Kondo model the Kondo temperature have been estimated. Magnetocaloric effect is small but shows a sign change, which may be caused by a metamagnetic behavior.

  18. Excitation of the OI (3s 5S0-3p 5P; lambda 7774 A) multiplet by electron impact on O2

    NASA Technical Reports Server (NTRS)

    Erdman, P. W.; Zipf, E. C.

    1987-01-01

    Electron impact on O2 has been employed to ascertain the absolute cross-section value and emission linewidths of the OI (3s 5S0-3p 5P; 7774 A) multiplet. The emission linewidths are highly Doppler-broadened in dissociative excitation, and display two distinct kinetic energy distributions: which indicate that both purely repulsive and discrete, bound, excited molecular states, which then predissociate, are involved in the dissociation process that leads to the excitation of OI 7774 A. The magnitude of the measured cross-section and the fragment kinetic energy distribution both indicate that the previous time-of-flight studies of the metastable OI (5S0) state require reinterpretation.

  19. Effect of fluorination on methyl internal rotation barriers: Microwave spectra of cyclopropylfluoromethyl silane (c-C3H5SiHFCH3) and cyclopropyldifluoromethyl silane (c-C3H5SiF2CH3)

    NASA Astrophysics Data System (ADS)

    Dorris, Rachel E.; Luce, Bailey C.; Stettner, Sarah J.; Peebles, Rebecca A.; Peebles, Sean A.; Bullard, John L.; Bunn, James E.; Guirgis, Gamil A.

    2015-12-01

    Rotational spectra for two conformers of c-C3H5SiHFCH3 (cyclopropylfluoromethyl silane, CFMS) and one conformer of c-C3H5SiF2CH3 (cyclopropyldifluoromethyl silane, CDFMS) have been observed by a combination of chirped-pulse and resonant cavity Fourier-transform microwave spectroscopy in the 7.5-16.5 GHz range. All rotational transitions were doubled by up to several megahertz into A and E states as a result of methyl group internal rotation, and analysis of measured transitions using a combined axis method yielded internal rotation barriers of ca. 6.0 kJ mol-1 for the two conformers of CFMS and ca. 5.2 kJ mol-1 for CDFMS, revealing a systematic decrease in the barrier as fluorine atoms are added to the silicon. Dipole moment information is also available for the CDFMS species.

  20. 75 FR 79368 - Tetrahydro-3, 5-dimethyl-2H-1, 3, 4-thiadiazine-2-thione; Amendment To Terminate and or Delete...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-20

    ... approved product labels reflecting the requested amendments to delete uses, registrants will be permitted... notice (75 FR 55327) announcing the Agency's receipt of the request to voluntarily amend registrations to... amend their tetrahydro-3, 5-dimethyl-2H-1, 3, 4-thiadiazine-2-thione (Dazomet) product registrations...

  1. Human Immunodeficiency Virus Type 2 (HIV-2) Gag Is Trafficked in an AP-3 and AP-5 Dependent Manner

    PubMed Central

    Alford, Justine E.; Marongiu, Michela; Watkins, Gemma L.

    2016-01-01

    Although human immunodeficiency virus (HIV) types 1 and 2 are closely related lentiviruses with similar replication cycles, HIV-2 infection is associated with slower progression to AIDS, a higher proportion of long term non-progressors, and lower rates of transmission than HIV-1, likely as a consequence of a lower viral load during HIV-2 infection. A mechanistic explanation for the differential viral load remains unclear but knowledge of differences in particle production between HIV-1 and HIV-2 may help to shed light on this issue. In contrast to HIV-1, little is known about the assembly of HIV-2 particles, and the trafficking of HIV-2 Gag, the structural component of the virus, within cells. We have established that HIV-2 Gag accumulates in intracellular CD63 positive compartments, from which it may be delivered or recycled to the cell surface, or degraded. HIV-2 particle release was dependent on the adaptor protein complex AP-3 and the newly identified AP-5 complex, but much less so on AP-1. In contrast, HIV-1 particle release required AP-1 and AP-3, but not AP-5. AP-2, an essential component of clathrin-mediated endocytosis, which was previously shown to be inhibitory to HIV-1 particle release, had no effect on HIV-2. The differential requirement for adaptor protein complexes confirmed that HIV-1 and HIV-2 Gag have distinct cellular trafficking pathways, and that HIV-2 particles may be more susceptible to degradation prior to release. PMID:27392064

  2. Three-step laser excitation of the 6p3/2ns, nd, ng autoionizing Rydberg levels via the 6p5f 1/2[5/2]2 level of lead

    NASA Astrophysics Data System (ADS)

    Ahad, A.; Nadeem, A.; Bhatti, S. A.; Baig, M. A.

    2005-03-01

    Odd parity autoionizing Rydberg levels of atomic lead in the energy region above the 6p1/2 ionization threshold have been investigated using three-step laser excitation in conjunction with an atomic beam apparatus. The 6p3/2ns (J = 1, 2), 6p3/2nd (J = 1, 2, 3) and 6p3/2ng (J = 2, 3) levels have been observed from the 6p5f 1/2[5/2]2 intermediate level. Energy values and FWHM of forty levels belonging to the 6p3/2ns, 6p3/2nd and 6p3/2ng configurations are presented. Six levels based on the 6p3/2ng (5, 13 ≤n ≤15) configurations and three levels attached to the 6p3/28d configuration are reported for the first time. The present study of the low-lying autoionizing levels attached to the 6p3/25g (J = 2, 3) configuration completes the series adjacent to the 6p1/2 limit.

  3. Improvement of cycling performance in Ti substituted 0.5Li2MnO3-0.5LiNi0.5Mn0.5O2 through suppressing metal dissolution

    NASA Astrophysics Data System (ADS)

    Yamamoto, Shinji; Noguchi, Hideyuki; Zhao, Wenwen

    2015-03-01

    Ti substituted 0.5Li2MnO3-0.5LiNi0.5Mn0.5O2 cathode material with the composition of Li1.5Ni0.25Mn0.75-xTixO2.5 has been synthesized by spray pyrolysis method. A great variety of characterization methods have been applied to study the influence of Ti substitution for Mn on the structural, morphological and electrochemical performances of Li1.5Ni0.25Mn0.75-xTixO2.5. X-ray diffraction (XRD) results of Li1.5Ni0.25Mn0.75-xTixO2.5 show that they exhibit similar XRD patterns as those of lithium-excess manganese metal oxide based cathode materials. It is confirmed from energy dispersive x-ray spectroscopy (EDX) data that Ti was homogenously substituted for Mn and well distributed in the host structure. X-ray absorption near edge structure (XANES) spectra analysis reveals that oxidation state of Mn in Li1.5Ni0.25Mn0.75-xTixO2.5 remains +4 while that of Ni changes from +2 to +4 during the initial activation process. Further investigation of the local structure of transition metal (TM) ions indicates that Ti has same coordination environment as that of Mn. Drastic capacity fade occurred in full cells with Li1.5Ni0.25Mn0.75O2.5 cathode and graphite anode, while full cell with Ti substituted cathode shows high capacity retention after 100 cycles. Further examination of the amount of dissolved transition metal (TM) ions after long cycling test enable us to demonstrate that substitution of Mn with Ti in Li1.5Ni0.25Mn0.75O2.5 has a significant impact on suppressing the TM ions dissolution and its deposition on both separator and anode thus leads to improved cycleability.

  4. Highly pathogenic influenza H5N1 virus of clade 2.3.2.1c in Western Siberia.

    PubMed

    Marchenko, V Y; Susloparov, I M; Kolosova, N P; Goncharova, N I; Shipovalov, A V; Ilyicheva, T N; Durymanov, A G; Chernyshova, O A; Kozlovskiy, L I; Chernyshova, T V; Pryadkina, E N; Karimova, T V; Mikheev, V N; Ryzhikov, A B

    2016-06-01

    In the spring of 2015, avian influenza virus surveillance in Western Siberia resulted in isolation of several influenza H5N1 virus strains. The strains were isolated from several wild bird species. Investigation of biological features of those strains demonstrated their high pathogenicity for mammals. Phylogenetic analysis of the HA gene showed that the strains belong to clade 2.3.2.1c. PMID:26935914

  5. Gamma ray shielding and structural properties of Bi2O3-PbO-B2O3-V2O5 glass system

    NASA Astrophysics Data System (ADS)

    Kaur, Kulwinder; Singh, K. J.; Anand, Vikas

    2014-04-01

    The present work has been undertaken to evaluate the applicability of Bi2O3-PbO-B2O3-V2O5 glass system as gamma ray shielding material. Gamma ray mass attenuation coefficient has been determined theoretically using WinXcom computer software developed by National Institute of Standards and Technology. A meaningful comparison of their radiation shielding properties has been made in terms of their half value layer parameter with standard radiation shielding concrete 'barite'. Structural properties of the prepared glass system have been investigated in terms of XRD and FTIR techniques in order to check the possibility of their commercial utility as alternate to conventional concrete for gamma ray shielding applications.

  6. Synthesis and Antifungal Activity of Natural Product-Based 6-Alkyl-2,3,4,5-tetrahydropyridines

    PubMed Central

    Dai, Liyan; Jacob, Melissa R.; Khan, Shabana I.; Khan, Ikhlas A.; Clark, Alice M.; Li, Xing-Cong

    2011-01-01

    Seven 6-alkyl-2,3,4,5-tetrahydropyridines (5a–5g) that mimic the natural piperideines that were recently identified in the fire ant venom have been synthesized. Compounds 5c–5g with the C-6 alkyl chain lengths from C14 to C18 showed varying degrees of antifungal activities, with 5e (6-hexadecyl-2,3,4,5-tetrahydropyridine) and 5f (6-heptadecyl-2,3,4,5-tetrahydropyridine) being the most active. Compound 5e exhibited minimum fungicidal concentrations (MFCs) of 3.8, 15.0, 7.5, and 7.5 μg/mL against Cryptococcus neoformans, Candida albicans, Candida glabrata, and Candida krusei, respectively. The antifungal activities of these compounds appear to be associated with the C-6 side chain length. This study represents the first effort to evaluate antifungal activities of synthetic analogs of the newly identified fire ant venom alkaloids. PMID:21905650

  7. Temperature dependence of optical properties (3HgSe)0.5(In2Se3)0.5, doped with Mn or Fe

    NASA Astrophysics Data System (ADS)

    Koziarskyi, I. P.; Marianchuk, P. D.; Maistruk, E. V.; Koziarskyi, D. P.

    2012-01-01

    The values of refraction index, the main reflection index and reflection coefficient for the investigated crystals were determined on the basis of the study of reflection and transmission coefficients of (3HgSe)0.5(In2Se3)0.5 crystals doped with Mn or Fe. The investigation was carried out on the wavelengths interval of 0.9<=λ<=26.6 μm. Basing on the dependencies α2 on the energy of incident electromagnetic radiation it was determined that in crystals the direct allowed interband optical transitions occur, and the value of the band gap was obtained. The influence of temperature on the optical transmittance has been studied in the interval of 120-300 K.

  8. Temperature dependence of optical properties (3HgSe)0.5(In2Se3)0.5, doped with Mn or Fe

    NASA Astrophysics Data System (ADS)

    Koziarskyi, I. P.; Marianchuk, P. D.; Maistruk, E. V.; Koziarskyi, D. P.

    2011-09-01

    The values of refraction index, the main reflection index and reflection coefficient for the investigated crystals were determined on the basis of the study of reflection and transmission coefficients of (3HgSe)0.5(In2Se3)0.5 crystals doped with Mn or Fe. The investigation was carried out on the wavelengths interval of 0.9<=λ<=26.6 μm. Basing on the dependencies α2 on the energy of incident electromagnetic radiation it was determined that in crystals the direct allowed interband optical transitions occur, and the value of the band gap was obtained. The influence of temperature on the optical transmittance has been studied in the interval of 120-300 K.

  9. SCC behavior of an Al-3. 7wt%Zn-2. 5wt%Mg alloys before and after welding in 3. 5% NaCl solution

    SciTech Connect

    Liao, C.M. )

    1993-01-01

    The behavior of stress corrosion cracking (SCC) of an overaged Al-3.7wt%Zn-2.5wt%Mg alloy including base metal, weldment, and heat-affected zone (HAZ) in 3.5% NaCl solution was investigated. This Al-Zn-Mg alloy loaded in longitudinal or long transverse direction has good SCC resistance and is maintained even after welding. Welding residual stress alone does not induce the SCC of the weldment. The result of the specially modified type 1 double cantilever beam (DCB) testing shows that the crack can be arrested by the weld metal because of the better SCC resistance of the filler metal ER5183. In addition, a specially designed type 2 DCB testing indicates that the SCC resistance of the HAZ is better than that of the base metal because of the re-overaging of the HAZ during welding.

  10. 40 CFR 721.5283 - Cobaltate (5-), bis[4-[[6-[(4-amino-6-chloro-1,3,5-triazin-2-yl)amio]-1-hydroxy-3-sulfo-2...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-2-naphthalenyl]azo]-3-hydroxy-7-nitro-1-naphthalenesulfonato(4-)]-, pentasodium. 721.5283 Section... Substances § 721.5283 Cobaltate (5-), bis -1-hydroxy-3-sulfo-2-naphthalenyl]azo]-3-hydroxy-7-nitro-1... chemical substance identified as cobaltate (5-), bis...

  11. 40 CFR 721.5283 - Cobaltate (5-), bis[4-[[6-[(4-amino-6-chloro-1,3,5-triazin-2-yl)amio]-1-hydroxy-3-sulfo-2...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-2-naphthalenyl]azo]-3-hydroxy-7-nitro-1-naphthalenesulfonato(4-)]-, pentasodium. 721.5283 Section... Substances § 721.5283 Cobaltate (5-), bis -1-hydroxy-3-sulfo-2-naphthalenyl]azo]-3-hydroxy-7-nitro-1... chemical substance identified as cobaltate (5-), bis...

  12. 40 CFR 721.5283 - Cobaltate (5-), bis[4-[[6-[(4-amino-6-chloro-1,3,5-triazin-2-yl)amio]-1-hydroxy-3-sulfo-2...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-2-naphthalenyl]azo]-3-hydroxy-7-nitro-1-naphthalenesulfonato(4-)]-, pentasodium. 721.5283 Section... Substances § 721.5283 Cobaltate (5-), bis -1-hydroxy-3-sulfo-2-naphthalenyl]azo]-3-hydroxy-7-nitro-1... chemical substance identified as cobaltate (5-), bis...

  13. Nonmagnetic ions enhance magnetic order in the ludwigite Co5Sn(O2BO3)2

    NASA Astrophysics Data System (ADS)

    Medrano, Cynthia P. Contreras; Freitas, D. C.; Sanchez, D. R.; Pinheiro, C. B.; Eslava, G. G.; Ghivelder, L.; Continentino, M. A.

    2015-02-01

    The ludwigite Co5Sn(O2BO3)2 was studied using x-ray diffraction, Mössbauer spectroscopy, and magnetic and thermodynamic measurements. This material belongs to a family of oxyborates which presents low-dimensional subunits in the form of three-leg ladders in its structure. The subunits confer to these materials a strong anisotropy in their exchange interactions that provide to the ludwigites several interesting magnetic properties, from partial ordering to spin-glass states. Despite being doped by nonmagnetic ions, Co5Sn(O2BO3)2 has long-range magnetic order below 82 K which is, surprisingly, the highest critical temperature found so far in the ludwigites. This record can be explained by the absence of double-exchange interactions, usually present in the ludwigites and that gives rise to strong competition. In this paper we study the magnetic and structural properties of Co5Sn(O2BO3)2 and compare our results with those obtained in other cobalt ludwigites.

  14. 40 CFR 721.9577 - Chromate(3-), bis[7-[(aminohydroxyphenyl)azo]-3-[[5-(aminosulfonyl)-2-hydroxyphenyl] azo]-4...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Chromate(3-), bis -3- azo]-4-hydroxy-2... Substances § 721.9577 Chromate(3-), bis -3- azo]-4-hydroxy-2-naphthalene sulfonato (3-)]-,- azo]-4-hydroxy-7... significant new uses subject to reporting. (1) The chemical substance identified as chromate(3-), bis -3-...

  15. 40 CFR 721.9577 - Chromate(3-), bis[7-[(aminohydroxyphenyl)azo]-3-[[5-(aminosulfonyl)-2-hydroxyphenyl] azo]-4...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Chromate(3-), bis -3- azo]-4-hydroxy-2... Substances § 721.9577 Chromate(3-), bis -3- azo]-4-hydroxy-2-naphthalene sulfonato (3-)]-,- azo]-4-hydroxy-7... significant new uses subject to reporting. (1) The chemical substance identified as chromate(3-), bis -3-...

  16. 40 CFR 721.9577 - Chromate(3-), bis[7-[(aminohydroxyphenyl)azo]-3-[[5-(aminosulfonyl)-2-hydroxyphenyl] azo]-4...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Chromate(3-), bis -3- azo]-4-hydroxy-2... Substances § 721.9577 Chromate(3-), bis -3- azo]-4-hydroxy-2-naphthalene sulfonato (3-)]-,- azo]-4-hydroxy-7... significant new uses subject to reporting. (1) The chemical substance identified as chromate(3-), bis -3-...

  17. 40 CFR 721.9577 - Chromate(3-), bis[7-[(aminohydroxyphenyl)azo]-3-[[5-(aminosulfonyl)-2-hydroxyphenyl] azo]-4...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Chromate(3-), bis -3- azo]-4-hydroxy-2... Substances § 721.9577 Chromate(3-), bis -3- azo]-4-hydroxy-2-naphthalene sulfonato (3-)]-,- azo]-4-hydroxy-7... significant new uses subject to reporting. (1) The chemical substance identified as chromate(3-), bis -3-...

  18. 40 CFR 721.9577 - Chromate(3-), bis[7-[(aminohydroxyphenyl)azo]-3-[[5-(aminosulfonyl)-2-hydroxyphenyl] azo]-4...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Chromate(3-), bis -3- azo]-4-hydroxy-2... Substances § 721.9577 Chromate(3-), bis -3- azo]-4-hydroxy-2-naphthalene sulfonato (3-)]-,- azo]-4-hydroxy-7... significant new uses subject to reporting. (1) The chemical substance identified as chromate(3-), bis -3-...

  19. Multiple charge-density-wave transitions in single-crystalline Lu2Ir3Si5

    NASA Astrophysics Data System (ADS)

    Sangeetha, N. S.; Thamizhavel, A.; Tomy, C. V.; Basu, Saurabh; Awasthi, A. M.; Rajak, Piu; Bhattacharyya, Somnath; Ramakrishnan, S.; Pal, D.

    2015-05-01

    The physical properties of the single-crystalline samples of Lu2Ir3Si5 have been investigated by magnetic susceptibility, resistivity, and heat capacity studies. We observed multiple charge-density-wave (CDW) transitions in all the measurements. A strong thermal hysteresis at these transitions suggests a possible first order CDW ordering. In addition, the first order nature is ascertained by a very narrow and a huge cusp (62 J/mol K) in the zero field specific heat data which also suggests strong electron-phonon interchain coupling.

  20. Antimicrobial effects of esters and amides of 3-(5-nitro-2-furyl)acrylic acid.

    PubMed

    Kellová, G; Sturdík, E; Stibrányi, L; Drobnica, L; Augustín, J

    1984-01-01

    The effect of 18 newly synthesized esters and amides of 3-(5-nitro-2-furyl)acrylic acid on bacteria (Escherichia coli, Staphylococcus aureus), yeasts (Saccharomyces cerevisiae, Candida albicans), molds (Aspergillus niger, Penicillium cyclopium, Rhizopus oryzae) and algae (Chlorella pyrenoidosa, Euglena gracilis, Scenedesmus obliquus) was investigated. The MIC values revealed antimycotic, antialgal and antibacterial activity of the studied derivatives. The antimycotic activity was found to decrease with increasing the length of the alkyl chain of esters and after introduction of amino nitrogen into the furylethylene backbone. The inhibitory effect on growth is caused by blocking bioenergetic processes, glycolysis in particular. PMID:6714854

  1. Photophysics of poly(2,3,4,5,6-pentafluorostyrene) film

    SciTech Connect

    O'Connor, D.B.; Scott, G.W. ); Coulter, D.R.; Miskowski, V.M.; Yavrouian, A. )

    1990-08-09

    The temperature-dependent steady-state emission, emission polarization anisotropy, and fluorescence kinetics of poly(2,3,4,5,6-pentafluorostyrene) film are reported. Two interconverting excited-state conformations of the chromophore have been identified. The fluorescence of the higher energy conformation results from excitation on the red edge of the polymer absorption band at temperatures below 180 K. The energy barrier for conversion of the higher energy conformer to the lower energy conformer is estimated to be E/hc = 27 {plus minus} 7 cm{sup {minus}1}. Electronic energy migration is not evident in this polymer.

  2. Preconcentration of cadmium and zinc with 1-phenyl-2, 3-dimethlypyrazolone-5-thione

    SciTech Connect

    Bikkulova, A.T.

    1985-08-20

    This paper attempts to ascertain the possibility of use of 1-phenyl-2,3-dimethyl-pyrazolone-5-thione (thiopyrine) for cadmium and zinc concentration in waste waters of oil refineries for their subsequent determination. Cadmium and zinc complexing with thiopyrine in aqueous solutions was studied by the distribution method. Cadmium and zinc in waste waters were determined by a neutron activation technique. The elemental composition and certain properties of halide complexes of cadmium and zinc with thiopyrine are shown. The constants of chloroform extraction of iodide complexes of cadmium and zinc with thiopyrine are shown.

  3. Synthesis, structural characterization and theoretical approach of 3-(2,6-dichlorobenzyl)-5-methyl-N-nitro-1,3,5-oxadiazinan-4-imine.

    PubMed

    Ni, Haiwei; Zhang, Yu; Zhang, Fang; Zhao, Jianying; Wu, Liubi; Chu, Xiaozhong

    2015-03-01

    3-(2,6-Dichlorobenzyl)-5-methyl-N-nitro-1,3,5-oxadiazinan-4-imine (DNOI) was synthesized and characterized by X-ray diffraction, FT-IR, FT-Raman and UV-Vis spectra. The X-ray diffraction study showed that DNOI has a one dimensional configuration, due to the intermolecular C9H⋯O1 and N4H⋯O2 hydrogen bonds. The benzene ring and the oxadiazine rings are tilted with respect to each other by 63.07° (C3N1C5C6). Vibrational spectra and electronic spectra measurements were made for the compound. Optimized geometrical structure and harmonic vibrational frequencies were computed with DFT (B3LYP, B3P86, and M062X) methods using 6-311++G(d,p) basis set. Assignments of the observed spectra were proposed. The equilibrium geometries computed by all of the methods were compared with X-ray diffraction results. The absorption spectra of the title compound were computed both in gas phase and in CH3OH solution using TD-B3LYP/6-311++G(d,p) and PCM-B3LYP/6-311++G(d,p) approaches, respectively. The calculated results provide a good description of positions of the bands maxima in the observed electronic spectrum. Temperature dependence of thermodynamic parameters in the range of 100-1000K were determined, entropy, heat capacity and enthalpy changes were increasing with temperature increasing, while for Gibbs free energy is decreasing with temperature increasing. The bond orbital occupancies, contribution from parent natural bond orbital (NBO), the natural atomic hybrids was calculated and discussed. PMID:25541404

  4. The MEF2C-Related and 5q14.3q15 Microdeletion Syndrome

    PubMed Central

    Zweier, M.; Rauch, A.

    2012-01-01

    Disorders related to the autosomal transcription factor MEF2C located in 5q14.3 were first described in 2009 and have since evolved to one of the more common microdeletion syndromes. Mutational screening in a larger cohort revealed heterozygous de novo mutations of MEF2C in about 1% of patients with moderate to severe intellectual disability, and the phenotype is similar in patients with intragenic deletions and multigenic microdeletions. Clinically, MEF2C-related disorders are characterized by severe intellectual disability with absent speech and limited walking abilities, hypotonia, seizures, and a variety of minor brain anomalies. The majority of patients show a similar facial gestalt with broad forehead, flat nasal bridge, hypotonic mouth, and small chin, as well as strabismus, but this phenotype is clinically not well recognized. The course of the disease is generally quite uniform, but patients with point mutations and smaller deletions seem to have a higher chance of walking skills and a lower risk of refractory seizures. Patients in whom the microdeletion also includes the RASA1 gene show features of the respective capillary and arterio-venous malformations and fistula syndrome. The phenotypic overlap with Rett syndrome is explained by a shared pathway and, accordingly, diminished MECP2 and CDKL5 expression is measureable in patients with MEF2C defects. Further research of this pathway may therefore eventually lead to a common therapeutic target. PMID:22670137

  5. Ab Initio Thermodynamic Study of the CO2 Capture Properties of Potassium Carbonate Sesquihydrate, K2CO3·1.5H2O

    SciTech Connect

    Duan, Yuhua; Luebkes,David R.; Pennline, Henry W; Li, Bingyun Li; Janik, Michael J.; Halley, Woods

    2012-01-01

    By combining density functional theory and lattice phonon dynamics, the thermodynamic properties of CO2 absorption/desorption reactions with dehydrated potassium carbonates through K2CO3·1.5H2O + CO2 = 2KHCO3 + 0.5H2O(g) are analyzed. The energy change and the chemical potential of this reaction have been calculated and used to evaluate its thermodynamic properties and phase transitions. The results indicate that the K2CO3·1.5H2O can only be applied for postcombustion CO2 capture technology at temperatures lower than its phase transition temperature, which depends on the CO2 pressure and the steam pressure with the best range being PH2O ≤ 1.0 bar. Above the phase transition temperature, the sorbent will be regenerated into anhydrous K2CO3. If the steam pressure PH2O is much greater than 1.0 bar, it is possible to use the K2CO3·1.5H2O sorbent for precombustion CO2 capture technology. Compared to anhydrous K2CO3, K2CO3·1.5H2O requires less energy for regeneration.

  6. New 1-(3-nitrophenyl)-5,6-dihydro-4H-[1,2,4]triazolo[4,3-a][1,5]benzodiazepines: synthesis and computational study.

    PubMed

    Kosychova, Lidija; Karalius, Antanas; Staniulytė, Zita; Sirutkaitis, Romualdas Aleksas; Palaima, Algirdas; Laurynėnas, Audrius; Anusevičius, Žilvinas

    2015-01-01

    Triazole derivatives constitute an important group of heterocyclic compounds have have been the subject of extensive study in the recent past. These compounds have shown a wide range of biological and pharmacological activities. In this work, new fused tricyclic 1-(3-nitrophenyl)-5,6-dihydro-4H-[1,2,4]triazolo[4,3-a][1,5]-benzodiazepines have been synthesized by the thermal cyclization of N'-(2,3-dihydro-1H-1,5-benzodiazepin-4-yl)-3-nitrobenzohydrazides. After screening ethanol, toluene and 1-butanol as solvents, butanol-1 was found to be the best choice for the cyclization reaction in order to obtain the highest yields of tricyclic derivatives. The chemical structures of the synthesized compounds were elucidated by the analysis of their IR, 1H- and 13C-NMR spectral data. For tentative rationalization of the reaction processes, the global and local reactivity indices of certain compounds, taking part in the reaction pathway, were assessed by means of quantum mechanical calculations using the conceptual density functional theory (DFT) approach. This work could be useful for the synthesis of new heterocyclic compounds bearing a fused triazole ring. PMID:25822079

  7. Versatile coordination modes of bis[5-(2-pyridine-2-yl)-1,2,4-triazole-3-yl]alkanes in Cu(II) complexes.

    PubMed

    Gusev, Alexey N; Nemec, Ivan; Herchel, Radovan; Bayjyyev, Eziz; Nyshchimenko, Galyna A; Alexandrov, Grigory G; Eremenko, Igor L; Trávníček, Zdeněk; Hasegawa, Miki; Linert, Wolfgang

    2014-05-21

    Nine new mononuclear and polynuclear Cu(II) complexes [Cu(H2L(2))Cl]Cl·3H2O (1), [Cu(H2L(3))Cl]Cl·H2O (2), [Cu(H2L(4))Cl]Cl·2.5H2O (3), [Cu3(μ(3)-L(1))2(H2O)3](ClO4)2·H2O (4), [Cu4(μ-HL(1))4](ClO4)8·CH3OH·5H2O (5), [Cu2(HL(3))2](ClO4)2·2H2O (6a), [Cu2(μ-HL(3))2](ClO4)2·H2O (6b), [Cu2(μ-HL(3))(L(3))Cu(teta)](ClO4)3·2H2O (7) and [Cu2(H2L(3))2(ox)](ClO4)2·2H22MeOH (8) containing [5-(2-pyridine-2-yl)-1,2,4-triazole-3-yl]alkanes (H2L(n), n = 1-4) in combination with other ligands, such as chlorido, aqua, triethylenetetramine (teta) and/or oxalato (ox(2-)), were synthesized and characterized by various techniques such as elemental analysis, FTIR, NMR and UV-Vis spectroscopy. X-ray structures of H2L(3) and H2L(4) as well as complexes 1-8 were determined. The X-ray structures revealed that relatively small composition and structural changes in the H2L(n) ligands have a substantial impact on the coordination geometries of the complexes themselves as well as on their resulting magnetic properties. It has been found that the geometries of the complexes vary from square-pyramidal to trigonal-bipyramidal (with τ ranging from 0.00 to 0.96) and, moreover, that the trigonal bipyramidal geometry becomes more preferable with the increase in the length of the polymethylene chain within the corresponding H2L(n) ligand. The magnetic properties of the polynuclear compounds 4, 5, 6, 7 and 8 were analysed using the spin Hamiltonian formalism, which revealed the presence of antiferromagnetic exchange in the polynuclear systems mediated by the title ligands. The significant effect of the geometric parameters on the Cu···Cu exchange interactions in the polynuclear complexes is discussed. PMID:24671486

  8. Zero photoelastic and water durable ZnO-SnO-P2O5-B2O3 glasses

    NASA Astrophysics Data System (ADS)

    Saitoh, Akira; Nakata, Kohei; Tricot, Grégory; Chen, Yuanyuan; Yamamoto, Naoki; Takebe, Hiromichi

    2015-04-01

    We report properties of zero birefringent xZnO-(67-x)SnO-(33-y)P2O5-y B2O3 glasses, within 18.5 ≤ x ≤ 22 and y = 0, 3, and 10 mol. %. These compositions of boro-phosphate glasses provide both zero photoelastic constant (PEC) and improved water durability. x = 19 and y = 3 compositions show minimum PEC of -0.002 × 10-12 Pa-1, which can contribute to candidate material for fiber current sensor devise without lead. The structures of zero photoelastic glasses were investigated by Raman scattering and nuclear magnetic resonance spectroscopies. Compositions of zero PEC glasses are explained by the empirical model proposed by Zwanziger et al. [Chem. Mater. 19, 286-290 (2007)].

  9. 5,5'-[(2,4-Dichloro-phen-yl)methyl-ene]bis-(2,2-dimethyl-1,3-dioxane-4,6-dione).

    PubMed

    Zeng, Wu-Lan

    2011-08-01

    The title compound, C(19)H(18)Cl(2)O(8), was prepared by the reaction of 2,2-dimethyl-1,3-dioxane-4,6-dione and 2,4-dichloro-benzaldehyde in ethanol. The two 1,3-dioxane rings exhibit boat conformations. In the crystal, mol-ecules are linked by weak inter-molecular C-H⋯O and C-H⋯Cl hydrogen bonds, forming chains parallel to the a axis. PMID:22090945

  10. Optical spectra of Er 3+ in Ba 2NaNb 5O 15 single crystals

    NASA Astrophysics Data System (ADS)

    Bigotta, S.; Gorini, G.; Toncelli, A.; Tonelli, M.; Cavalli, E.; Bovero, E.

    2006-03-01

    The absorption and luminescence spectra of Er3+-doped Ba2NaNb5O15 single crystals have been measured at 10 and 298 K. The lifetimes of the lower lying excited states, emitting in the visible and NIR regions, have been measured as a function of the temperature. From the oscillator strengths of the absorption transitions, the Judd-Ofelt intensity parameters have been evaluated. The spontaneous transition probabilities, the branching ratios and the radiative lifetimes have been determined for the most important emitting states using the calculated intensity parameters and the results have been compared with the experimental data. The stimulated emission cross section have been estimated for the 1.5 μm transition. These experimental results are discussed in order to evaluate the potentialities of this material as active medium in solid state laser devices.

  11. A Mononuclear Fe(III) Single Molecule Magnet with a 3/25/2 Spin Crossover

    PubMed Central

    Tran, Ba L.; Adhikari, Debashis; Pink, Maren; Heinemann, Frank W.; Sutter, Jörg; Szilagyi, Robert K.

    2012-01-01

    The air stable complex [(PNP)FeCl2] (1) (PNP = N[2-P(CHMe2)2-4-methylphenyl]2−), prepared from one-electron oxidation of [(PNP)FeCl] with ClCPh3, displays an unusual S = 3/2 to S = 5/2 transition above 80 K as inferred by the dc SQUID magnetic susceptibility measurement. The ac SQUID magnetization data, at zero field and between frequencies 10 and 1042 Hz, clearly reveals complex 1 to undergo a frequency dependent of the out-of-phase signal and thus be a single molecular magnet with a thermally activated barrier of Ueff = 32-36 cm−1 (47 - 52 K). Variable temperature Mössbauer data also corroborate a significant temperature dependence in δ and ΔEQ values for 1, which is in agreement with the system undergoing a change in spin state. Likewise, variable temperature X-band EPR spectra of 1 reveals the S = 3/2 to be likely the ground state with the S = 5/2 being close in energy. Multi-edge XAS absorption spectra suggest the electronic structure of 1 to be highly covalent with an effective iron oxidation state that is more reduced than the typical ferric complexes due to the significant interaction of the phosphine groups in PNP and Cl ligands with iron. A variable temperature single crystal X-ray diffraction study of 1 collected between 30-300 K also reveals elongation of the Fe–P bond lengths and increment in the Cl–Fe–Cl angle as the S = 5/2 state is populated. Theoretical studies show overall similar orbital pictures except for the d(z2) orbital which is the most sensitivity to change in the geometry and bonding where the quartet (4B) and the sextet (6A) states are close in energy. PMID:22817325

  12. Selectivity of substrate binding and ionization of 2-methyl-3-hydroxypyridine-5-carboxylic acid oxygenase.

    PubMed

    Luanloet, Thikumporn; Sucharitakul, Jeerus; Chaiyen, Pimchai

    2015-08-01

    2-Methyl-3-hydroxypyridine-5-carboxylic acid (MHPC) oxygenase (EC 1.14.12.4) from Pseudomonas sp. MA-1 is a flavin-dependent monooxygenase that catalyzes a hydroxylation and aromatic ring cleavage reaction. The functional roles of two residues, Tyr223 and Tyr82, located ~ 5 Å away from MHPC, were characterized using site-directed mutagenesis, along with ligand binding, product analysis and transient kinetic experiments. Mutation of Tyr223 resulted in enzyme variants that were impaired in their hydroxylation activity and had Kd values for substrate binding 5-10-fold greater than the wild-type enzyme. Because this residue is adjacent to the water molecule that is located next to the 3-hydroxy group of MHPC, the results indicate that the interaction between Tyr223, H2 O and the 3-hydroxyl group of MHPC are important for substrate binding and hydroxylation. By contrast, the Kd for substrate binding of Tyr82His and Tyr82Phe variants were similar to that of the wild-type enzyme. However, only ~ 40-50% of the substrate was hydroxylated in the reactions of both variants, whereas most of the substrate was hydroxylated in the wild-type enzyme reaction. In free solution, MHPC or 5-hydroxynicotinic acid exists in a mixture of monoanionic and tripolar ionic forms, whereas only the tripolar ionic form binds to the wild-type enzyme. The binding of tripolar ionic MHPC would allow efficient hydroxylation through an electrophilic aromatic substitution mechanism. For the Tyr82His and Tyr82Phe variants, both forms of substrates can bind to the enzymes, indicating that the mutation at Tyr82 abolished the selectivity of the enzyme towards the tripolar ionic form. Transient kinetic studies indicated that the hydroxylation rate constants of both Tyr82 variants are approximately two- to 2.5-fold higher than that of the wild-type enzyme. Altogether, our findings suggest that Tyr82 is important for the binding selectivity of MHPC oxygenase towards the tripolar ionic species, whereas the

  13. Heterometallic aggregates of copper(I) with metalloligand Sn(edt)2 (edt = ethane-1,2-dithiolate): syntheses and structures of [Sn(edt)2Cl(mu-I)(mu3-I)(CuPPh3)3], [Sn(edt)2(mu-Br)2(mu3-Br)2(CuPPh3)4], and [{Sn(edt)2}3(mu-OH)3Cu5(PPh3)8][PF6]2.

    PubMed

    Han, Yan-Gong; Xu, Chao; Duan, Taike; Wu, Fang-Hui; Zhang, Qian-Feng; Leung, Wa-Hung

    2009-09-21

    The treatment of a slurry of an equimolar mixture of [Sn(edt)(2)] (edt = ethane-1,2- dithiolate) and [Et(4)N]Cl.xH(2)O with CuI in the presence of PPh(3) gave a tetranuclear compound, [Sn(edt)(2)Cl(mu-I)(mu(3)-I)(CuPPh(3))(3)] (1), which consists of a rectangular-pyramidal [Sn(edt)(2)Cl](-) moiety ligated by three [Cu(PPh(3))](+) fragments via the sulfur atoms of the edt(2-) ligands. The treatment of a slurry of [Sn(edt)(2)] and excess [Et(4)N]Br with [Cu(MeCN)(4)][PF(6)] in the presence of PPh(3) afforded a pentanuclear compound, [Sn(edt)(2)(mu-Br)(2)(mu(3)-Br)(2)(CuPPh(3))(4)] (2), which comprises two [(CuPPh(3))(2)(mu-Br)](+) fragments symmetrically ligating an octahedral trans-[Sn(edt)(2)Br(2)](2-) moiety via the sulfur and bromide atoms. Reaction of [Sn(edt)(2)] with [Cu(MeCN)(4)][PF(6)] and PPh(3) in a mixed MeCN/CH(2)Cl(2) solution yielded a novel octanuclear compound, [{Sn(edt)(2)}(3)(mu-OH)(3)Cu(5)(PPh(3))(8)][PF(6)](2) (3), which may be described as a triangular [{Sn(edt)(2)}(3)(mu-OH)(3)](3-) core chelated by three [Cu(PPh(3))(2)](+) species and capped by two [Cu(PPh(3))](+) species. The luminescent properties of compounds 1, 2, and 3 were investigated in a CH(2)Cl(2) solution at room temperature. Upon excitation at lambda > 360 nm, these compounds are luminescent in CH(2)Cl(2) solution with emissions having maxima at 422, 515, and 494 nm, respectively. PMID:19746999

  14. Satellite Quenching and Galactic Conformity at 0.3 < z < 2.5

    NASA Astrophysics Data System (ADS)

    Kawinwanichakij, Lalitwadee; Quadri, Ryan F.; Papovich, Casey; Kacprzak, Glenn G.; Labbé, Ivo; Spitler, Lee R.; Straatman, Caroline M. S.; Tran, Kim-Vy H.; Allen, Rebecca; Behroozi, Peter; Cowley, Michael; Dekel, Avishai; Glazebrook, Karl; Hartley, W. G.; Kelson, Daniel D.; Koo, David C.; Lee, Seong-Kook; Lu, Yu; Nanayakkara, Themiya; Persson, S. Eric; Primack, Joel; Tilvi, Vithal; Tomczak, Adam R.; van Dokkum, Pieter

    2016-01-01

    We measure the evolution of the quiescent fraction and quenching efficiency of satellites around star-forming and quiescent central galaxies with stellar mass {log}({M}{cen}/{M}⊙ )\\gt 10.5 at 0.3\\lt z\\lt 2.5. We combine imaging from three deep near-infrared-selected surveys (ZFOURGE/CANDELS, Ultra Deep Survey, and UltraVISTA), which allows us to select a stellar-mass complete sample of satellites with {log}({M}{sat}/{M}⊙ )\\gt 9.3. Satellites for both star-forming and quiescent central galaxies (“centrals”) have higher quiescent fractions compared to field galaxies matched in stellar mass at all redshifts. We also observe “galactic conformity”: satellites around quiescent centrals are more likely to be quenched compared to the satellites around star-forming centrals. In our sample, this conformity signal is significant at ≳ 3σ for 0.6\\lt z\\lt 1.6, whereas it is only weakly significant at 0.3\\lt z\\lt 0.6 and 1.6\\lt z\\lt 2.5. Therefore, conformity (and thus satellite quenching) has been present for a significant fraction of the age of the universe. The satellite quenching efficiency increases with increasing stellar mass of the central, but does not appear to depend on the stellar mass of the satellite to the mass limit of our sample. When we compare the satellite quenching efficiency of star-forming centrals with stellar masses 0.2 dex higher than quiescent centrals (which should account for any difference in halo mass), the conformity signal decreases, but remains statistically significant at 0.6\\lt z\\lt 0.9. This is evidence that satellite quenching is connected to the star formation properties of the central galaxy as well as to the mass of the halo. We discuss physical effects that may contribute to galactic conformity, and emphasize that they must allow for continued star formation in the central galaxy even as the satellites are quenched. This paper includes data gathered with the 6.5 meter Magellan Telescopes located at Las Campanas

  15. Preparation, properties, and reactivities of unprecedented oxo-sulfido Nb(IV) aqua ions and crystal structure of (Me2NH2)6[Nb5(mu3-S)2(mu3-O)2(mu2-O)2(NCS)14].3.5H2O.

    PubMed

    Ooi, Bee-Lean; Søtofte, Inger; Sokolov, Maxim N; Kozlova, Svetlana G; Rasmussen, Søren B; Nielsen, Loa C; Henriksen, Jonas

    2006-06-26

    By treatment of Zn-reduced ethanolic solutions of NbCl5 with HCl in the presence of sulfide followed by cation-exchange chromatography, two oxo-sulfido niobium aqua ions, the red [Nb4(mu4-S)(mu2-O)5(H2O)10]4+ and the yellow-brown [Nb5(mu3-S)2(mu3-O)2(mu2-O)2(H2O)14]8+, were isolated. Both readily form their respective thiocyanate complexes, for which the structure for the former has been previously reported. Brown crystals of (Me2NH2)6[Nb5S2O4(NCS)14].3.5H2O (1) were isolated in the case of the latter, and the structure was determined by X-ray crystallography (space group: a = 15.4018(5) A, b = 21.1932(8) A, c = 22.0487(8) A, alpha=gamma = 90 degrees , beta = 103.4590(10) degrees , and R(1) = 0.0659). An unprecedented pentanuclear Nb5S2O48+ core is revealed in which short Nb-Nb distances (2.7995(8)-2.9111(8) A) are consistent with metal-metal bonding. A stopped-flow kinetic study of the 1:1 equilibration of NCS- with [Nb4(mu4-S)(mu2-O)5(H2O)10]4+ has been carried out. Equilibration rate constants are independent of [H(+)] in the range investigated (0.5-2.0 M) and at 25 degrees C; kf= 9.5 M(-1) s(-1), kaq = 2.6 x 10(-2) s(-1), and K = 365 M1). Conditions with first NCS- and then [Nb4(mu4-S)(mu2-O)5(H2O)10]4+ in excess revealed a statistical factor of 4, suggesting the presence of four kinetically equivalent Nb atoms. Attempts to study the 1:1 substitution of NCS- with [Nb5(mu3-S)2(mu3-O)2(mu2-O)2(H2O)14]8+ showed signs of saturation kinetics. Quantum chemical calculations using the density functional theory (DFT) approach were performed on both the Nb4O5S4+ and Nb5O4S28+ naked clusters. The highest occupied and lowest unoccupied molecular orbitals have dominant Nb(4d) character. The HOMO for Nb4O5S4+ is a nondegenerate fully filled MO, whereas for Nb5O4S28+, it is a nondegenerate partially filled MO with one unpaired electron. EPR spectroscopy on [Nb5(mu3-S)2(mu3-O)2(mu2-O)2(H2O)14]8+ shows that the molecule has total anisotropy (C2v), with all three tensors, gx= 2

  16. Selection of different sintering aids and heat-treatment of Y2O3 raw powders for Yb3+:Y3Al5O12 transparent ceramics

    NASA Astrophysics Data System (ADS)

    Chen, Chong; Zhou, Shengming; Lin, Hui; Yi, Qing

    2011-11-01

    La2O3, Y2O3, ZrO2, and MgO+TEOS were added as the sintering aid to prepare Yb3+:Y3Al5O12 transparent ceramics. Pre-calcination was adopted to improve the crystalline quality and morphology of the commercially available Y2O3 raw powders. The non-stoichiometricaly doped La2O3, Y2O3, and ZrO2 enhanced the grain boundary mobility so fast that abnormal grain growth occurred and pores tended to be enclosed in these grains. It was found that MgO+TEOS had a positive effect on full densification of the Yb:YAG ceramics. The grain boundaries moved moderately so that pores could be eliminated well and meanwhile the grains would not get too large. Laser output experiment was also carried out for the Yb:YAG transparent ceramics.

  17. Selection of different sintering aids and heat-treatment of Y2O3 raw powders for Yb3+:Y3Al5O12 transparent ceramics

    NASA Astrophysics Data System (ADS)

    Chen, Chong; Zhou, Shengming; Lin, Hui; Yi, Qing

    2012-01-01

    La2O3, Y2O3, ZrO2, and MgO+TEOS were added as the sintering aid to prepare Yb3+:Y3Al5O12 transparent ceramics. Pre-calcination was adopted to improve the crystalline quality and morphology of the commercially available Y2O3 raw powders. The non-stoichiometricaly doped La2O3, Y2O3, and ZrO2 enhanced the grain boundary mobility so fast that abnormal grain growth occurred and pores tended to be enclosed in these grains. It was found that MgO+TEOS had a positive effect on full densification of the Yb:YAG ceramics. The grain boundaries moved moderately so that pores could be eliminated well and meanwhile the grains would not get too large. Laser output experiment was also carried out for the Yb:YAG transparent ceramics.

  18. Predictors of urinary levels of 2,4-dichlorophenoxyacetic acid, 3,5,6-trichloro-2-pyridinol, 3-phenoxybenzoic acid, and pentachlorophenol in 121 adults in Ohio

    EPA Science Inventory

    Limited data exist on the driving factors that influence the non-occupational exposures of adults to pesticides using urinary biomonitoring. In this work, the objectives were to quantify the urinary levels of 2,4-dichlorophenoxyacetic acid (2,4-D), 3,5,6-trichloro-2-pyridinol (TC...

  19. Energy levels and crystal field parameters for Nd3+ ions in BaY2F8, LiKYF5, and K2YF5 single crystals.

    PubMed

    Karbowiak, M; Gnutek, P; Rudowicz, C

    2012-02-15

    The available experimental energy levels of Nd(3+) ions doped into single crystals of BaY(2)F(8), LiKYF(5), and K(2)YF(5), which exhibit low site symmetry, are reanalyzed. A combined approach based on the ascent/descent in symmetry (ADS) method, the superposition model (SPM) analysis, and the pseudosymmetry axes method (PAM) is utilized to extract the crystal field (CF) parameters, B(kq), from experimental spectra. Corresponding sets of the free-ion parameters are also fitted. The crystallographic data are used to establish the axis systems most appropriate for approximation of the actual monoclinic C(2) site symmetry to higher orthorhombic D(2) and tetragonal D(4) symmetry used in CF calculations for BaY(2)F(8). Similarly, for triclinic C(1) site symmetry in LiKYF(5) and K(2)YF(5) approximation to monoclinic C(2) and orthorhombic D(2) symmetry for LiKYF(5), whereas the monoclinic C(s) symmetry for K(2)YF(5), are considered. It is shown that the C(2v) approximation used previously for K(2)YF(5):Nd(3+) is not suitable. SPM enables to calculate for the unapproximated and idealized polyhedrons YF(8) in a given ion-host system of the combined coordination factors Sg(k,q) expressed in the modified crystallographic axis system CAS* and approximated symmetry adapted axis systems, respectively. The quantities Sg(k,q) serve as input for PAM calculations for independent determination of the axis system appropriate for higher symmetry approximations. The pseudosymmetry axes represent the axis system that reflects most closely the approximated higher symmetry of the nearest ligands in a paramagnetic complex embodied in the 4th-rank CF parameters. The combined ADS/SPM/PAM approach provides sets of starting CF parameters (CFPs) in well-defined axis systems. Multiple fittings starting from different points in the CF parameter space yield converging solutions, thus increasing the reliability of the final optimized solutions, which may be then considered as the global minima. The

  20. MEASUREMENT OF THE RADIATIVE DECAY RATE OF THE METASTABLE (2s {sup 2}2p {sup 5}{sub 3/2}3s{sub 1/2}){sub (J=2)} LEVEL IN Fe XVII

    SciTech Connect

    Crespo Lopez-Urrutia, J. R.; Beiersdorfer, P.

    2010-09-20

    The radiative decay rate of the (2s {sup 2}2p {sup 5}{sub 3/2}3s{sub 1/2}){sub J=2} {yields} (2s {sup 2}2p {sup 6}){sub J=0} transition was measured in Ne-like Fe XVII. This transition forms the prominent magnetic quadrupole line, dubbed M2 or 3H, in the Fe XVII spectrum at 17.10 A. Different theoretical models predict radiative rates for this transition that diverge by almost a factor of 2, making intensity predictions for this line uncertain in environments where it is affected by de-excitation due to either electron-impact collisions or photoionization. Our result of (2.04{sup +0.03}{sub -0.09}) x 10{sup 5} s{sup -1} is very close to the value of 2.06 x 10{sup 5} s{sup -1} predicted by the Flexible Atomic Code.

  1. Specific heat anomaly in ferroelectric: Bis(imidazolium) pentachloroantimonate(III) (C3 N2 H5)2[SbCl5

    NASA Astrophysics Data System (ADS)

    Przesławski, J.; Piecha-Bisiorek, A.; Jakubas, R.

    2016-04-01

    Single crystals of ferroelectric bis(imidazolium) pentachloroantimonate(III) (C3N2H5)2 [SbCl5 ] have been grown and the heat capacity was measured by the use of AC calorimetric method. The temperature dependence of excess heat capacity and excess entropy in the ferroelectric phase can be described in the frame of the classical Landau-Devonshire theory of phase transitions. The results of experimental studies were analyzed and the α, γ and δ values of the Landau potential coefficients were calculated. The temperature dependence of the order parameter was also evaluated from the heat capacity data.

  2. Copper(I)/Ligand-Catalyzed 5-endo Radical Cyclization-Aromatization of 2,2,2-Trichloroethyl Vinyl Ethers: Synthesis of 2,3-Difunctionalized 4-Chlorofurans.

    PubMed

    Ram, Ram N; Gupta, Dharmendra Kumar; Soni, Vineet Kumar

    2016-02-19

    Copper(I)/ligand-catalyzed one pot synthesis of highly substituted 2,3-difunctionalized-4-chlorofurans has been reported. The reaction proceeds via a Cu(I)-catalyzed regioselective 5-endo-trig radical cyclization of 2,2,2-trichloroethyl vinyl ethers followed by the base-promoted dehydrochlorination. The success of the kinetically disfavored 5-endo cyclization was attributed to the formation of captodatively stabilized radical intermediate in the cyclization step and relatively high reaction temperature. Synthetic application of this protocol was also demonstrated in the preparation of alkyl and aryl substituted 4-chlorofuranonapthoquinones. PMID:26796068

  3. Synthesis and Piezoelectric Properties Nd2O3-doped BaTiO3-Bi0.5(Na, K)0.5TiO3 by a Novel Composite-hydroxide-mediated Approach

    NASA Astrophysics Data System (ADS)

    Kimura, T.; Yin, S.; Hashimoto, T.; Sasaki, A.; Tokano, Y.; Sato, T.

    2011-10-01

    High purity Nd2O3-doped (1-x)BaTiO3-xBi0.5(Na, K)0.5TiO3 (x = 0.00-0.08) were synthesized by a composite-hydroxide-mediated approach at 200°C using a hydrothermal reaction apparatus with a rolling system. The powders with an average size of 100 nm in diameter were produced and were sintered to almost full theoretical density at low temperature such as 1200°C for 2 h. Although (1--x)BaTiO3-xBi0.5(Na, K)0.5TiO3 could not be poled, Nd2O3 additive was useful to proceed the polarization of (1-x)BaTiO3-xBi0.5(Na, K)0.5TiO3 ceramics.

  4. Passively mode-locked Yb3+:Sc2SiO5 thin-disk laser.

    PubMed

    Wentsch, Katrin Sarah; Zheng, Lihe; Xu, Jun; Ahmed, Marwan Abdou; Graf, Thomas

    2012-11-15

    Experimental investigations on a passively mode-locked Yb(3+):Sc(2)SiO(5) (Yb:SSO) thin-disk laser are presented. The mode-locking was performed with a commercially available semiconductor saturable absorber mirror. The laser was operated at a repetition rate of 27 MHz and generated a maximum average output power of 27.8 W with a pulse duration of 298 fs. The spectrum was centered at 1036 nm. The beam was measured to be close to diffraction limited (M(2)<1.1). The promising results confirm the suitability of Yb:SSO for mode-locked thin-disk laser oscillators and indicate that this comparably new material deserves further attention by optimizing the crystal quality (growth and polishing) and doping levels for further power scaling. PMID:23164901

  5. Electrical Characterization of Photodetectors Based on Poly(3-hexylthiophene-2,5-diyl) Layers

    PubMed Central

    Ferrer, Juan Carlos; Alonso, José Luis; de Ávila, Susana Fernández

    2014-01-01

    This paper presents the electrical characteristics of solution-processed organic photodetectors based on poly(3-hexylthiophene-2,5-diyl) semiconducting polymer layers deposited by spin-coating on interdigitated metal electrodes. Four different electrode shapes have been used for this study in order to appraise the optimum electrode geometry. The measurement of the resistance as a function of the temperature reveals a transition from negative to positive temperature coefficient material around 80 °C for the polymer layers. Besides, slow reversible changes in the photodetectors conductivity were observed when moved from vacuum to the air and under illumination with a xenon lamp, which can be explained by the formation of charge transfer complexes with molecular oxygen and the polymer. The photogenerated current-light power ratio was found to be approximately linear in the 200 to 550 mW/cm2 range. PMID:24662451

  6. Preliminary toxicology study of 3,6-diamino-1,2,4,5-tetrazine

    SciTech Connect

    London, J.E.

    1993-03-01

    The calculated acute oral LD 30/50 (lethal dose for 50% of the animals occurring within 30 days after compound administration) value for 3,6-diamino-1,2,4,5-tetrazine (DATZ) was 863 mg/kg in rats. According to classical guidelines, DATZ would be considered slightly to moderately toxic for rats. The calculated acute oral LD {sub 30/50} value was 2,288 mg/kg in mice and would be considered slightly to moderately toxic for mice. Skin application studies using rabbits demonstrated DATZ to be a nonirritant. The eye study using rabbits disclosed DATZ to be a very mild irritant. The sensitization study using guinea pigs did not show DATZ to have potential sensitizing properties.

  7. Preliminary toxicology study of 3,6-diamino-1,2,4,5-tetrazine

    SciTech Connect

    London, J.E.

    1993-03-01

    The calculated acute oral LD 30/50 (lethal dose for 50% of the animals occurring within 30 days after compound administration) value for 3,6-diamino-1,2,4,5-tetrazine (DATZ) was 863 mg/kg in rats. According to classical guidelines, DATZ would be considered slightly to moderately toxic for rats. The calculated acute oral LD [sub 30/50] value was 2,288 mg/kg in mice and would be considered slightly to moderately toxic for mice. Skin application studies using rabbits demonstrated DATZ to be a nonirritant. The eye study using rabbits disclosed DATZ to be a very mild irritant. The sensitization study using guinea pigs did not show DATZ to have potential sensitizing properties.

  8. Ethyl (Z)-2-(2-fluoro­benzyl­idene)-7-methyl-3-oxo-5-phenyl-3,5-dihydro-2H-thia­zolo[3,2-a]pyrimidine-6-carboxyl­ate

    PubMed Central

    Zhao, Cheng-Guang; Hu, Jie; Zhang, Ya-Li; Zhang, Jing; Yang, Shu-Lin

    2011-01-01

    The title compound, C23H19FN2O3S, a fused-pyrimidine derivative, displays dihedral angles between the thia­zole ring and the benzene ring and substituted benzene ring of 7.10 (14) and 3.48 (12)°, respectively. The dihydro­pyrimidine ring adopts a flattened boat conformation. The olefinic double bond is in a Z configuration. PMID:22220026

  9. 40 CFR 721.9750 - 2-Chloro-4,6-bis(substituted)-1,3,5-triazine, dihydrochloride.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 2-Chloro-4,6-bis(substituted)-1,3,5... New Uses for Specific Chemical Substances § 721.9750 2-Chloro-4,6-bis(substituted)-1,3,5-triazine... identified generically as 2-chloro-4,6-bis(substituted)-1,3,5-triazine, dihydrochloride (PMN P-91-659)...

  10. Surface Collective Modes in the Topological Insulators Bi2 Se3 and Bi0.5 Sb1.5 Te3 -xSex

    NASA Astrophysics Data System (ADS)

    Kogar, A.; Vig, S.; Thaler, A.; Wong, M. H.; Xiao, Y.; Reig-i-Plessis, D.; Cho, G. Y.; Valla, T.; Pan, Z.; Schneeloch, J.; Zhong, R.; Gu, G. D.; Hughes, T. L.; MacDougall, G. J.; Chiang, T.-C.; Abbamonte, P.

    2015-12-01

    We used low-energy, momentum-resolved inelastic electron scattering to study surface collective modes of the three-dimensional topological insulators Bi2 Se3 and Bi0.5 Sb1.5 Te3 -xSex . Our goal was to identify the "spin plasmon" predicted by Raghu and co-workers [Phys. Rev. Lett. 104, 116401 (2010)]. Instead, we found that the primary collective mode is a surface plasmon arising from the bulk, free carriers in these materials. This excitation dominates the spectral weight in the bosonic function of the surface χ"(q ,ω ) at THz energy scales, and is the most likely origin of a quasiparticle dispersion kink observed in previous photoemission experiments. Our study suggests that the spin plasmon may mix with this other surface mode, calling for a more nuanced understanding of optical experiments in which the spin plasmon is reported to play a role.

  11. Synthesis of Substituted Tetralins and Benzosuberans via BF3·OEt2-Mediated Formal (4 + 2) and (5 + 2) Stereocontrolled Cycloaddition of 4-Alkenols with Veratrol.

    PubMed

    Chang, Meng-Yang; Cheng, Yu-Chieh

    2016-02-01

    BF3·OEt2-mediated one-pot formal (4 + 2) and (5 + 2) stereocontrolled cycloaddition of 4-alkenols 3 and 4 with veratrol affords the respective substituted tetralins 5 and benzosuberans 6 in good yields. The cascade protocol combines a facile double Friedel-Crafts benzannulation of 4-alkenols 3 and 4 (having two electrophilic sites) and veratrol (7a) (having two nucleophilic sites). A plausible mechanism was studied and proposed. PMID:26743459

  12. Synthesis and antimalarial activity of 3,3-spiroanellated 5,6-disubstituted 1,2,4-trioxanes.

    PubMed

    Maurya, Ranjani; Soni, Awakash; Anand, Devireddy; Ravi, Makthala; Raju, Kanumuri S R; Taneja, Isha; Naikade, Niraj K; Puri, S K; Wahajuddin; Kanojiya, Sanjeev; Yadav, Prem P

    2013-02-14

    Novel 3,3-spiroanellated 5-aryl, 6-arylvinyl-substituted 1,2,4-trioxanes 19-34 have been synthesized and appraised for their antimalarial activity against multidrug-resistant Plasmodium yoelii nigeriensis in Swiss mice by oral route at doses ranging from 96 mg/kg × 4 days to 24 mg/kg × 4 days. The most active compound of the series (compound 25) provided 100% protection at 24 mg/kg × 4 days, and other 1,2,4-trioxanes 22, 26, 27, and 30 also showed promising activity. In this model, β-arteether provided 100 and 20% protection at 48 mg/kg × 4 days and 24 mg/kg × 4 days, respectively, by oral route. Compound 25 displayed a similar in vitro pharmacokinetic profile to that of reference drug β-arteether. The activity results demonstrated the importance of an aryl moiety at the C-5 position on the 1,2,4-trioxane pharmacophore. PMID:24900640

  13. Antitumor agents. 1. Synthesis, biological evaluation, and molecular modeling of 5H-pyrido[3,2-a]phenoxazin-5-one, a compound with potent antiproliferative activity.

    PubMed

    Bolognese, Adele; Correale, Gaetano; Manfra, Michele; Lavecchia, Antonio; Mazzoni, Orazio; Novellino, Ettore; Barone, Vincenzo; Pani, Alessandra; Tramontano, Enzo; La Colla, Paolo; Murgioni, Chiara; Serra, Ilaria; Setzu, Giovanna; Loddo, Roberta

    2002-11-21

    The iminoquinone is an important moiety of a large number of antineoplastic drugs and plays a significant role in the nucleus of actinomycins, powerful, highly toxic, natural antibiotics that target DNA as intercalating agents. A series of polycyclic iminoquinonic compounds, 2-amino-3H-phenoxazin-3-one (1), 2-amino-1,9-diacetyl-3H-phenoxazin-3-one (2), 2-acetylamino-3H-phenoxazin-3-one (3), 3H-phenoxazin-3-one (4), 5H-pyrido[3,2-a]phenoxazin-5-one (5), and 5H-pyrido[3,2-a]phenothiazin-5-one (6), strictly related to the actinomycin chromophore, were synthesized for developing new anticancer intercalating drugs. The antiproliferative activity of these compounds, evaluated against representative human liquid and solid neoplastic cell lines, showed that 5 and its isoster 6 were the most active compounds inhibiting cell proliferation in a submicromolar range. Compound 5 was also evaluated against KB subclones (KBMDR, KB7D, and KBV20C), which overexpress the MDR1/P-glycoprotein drug efflux pump responsible for drug resistance. All the above KB subclones did not show altered sensitivity to the antiproliferative activity of 5. UV-vis and (1)H NMR spectroscopy experiments support the phenoxazinone 5/DNA binding. Molecular mechanics methods were used to build a three-dimensional model of the 5/[d(GAAGCTTC)]2 complex. Electrostatic interactions between the hydrogen of the positively charged pyridine nitrogen of 5 and the negatively charged oxygen atoms (O4' and O5') of the cytosine C5 residue together with stacking forces contribute to the high antiproliferative activity. The metal(II)-assisted synthesis procedure of 5 is described, and the formation mechanism is proposed. PMID:12431048

  14. Orbital-Optimized MP3 and MP2.5 with Density-Fitting and Cholesky Decomposition Approximations.

    PubMed

    Bozkaya, Uğur

    2016-03-01

    Efficient implementations of the orbital-optimized MP3 and MP2.5 methods with the density-fitting (DF-OMP3 and DF-OMP2.5) and Cholesky decomposition (CD-OMP3 and CD-OMP2.5) approaches are presented. The DF/CD-OMP3 and DF/CD-OMP2.5 methods are applied to a set of alkanes to compare the computational cost with the conventional orbital-optimized MP3 (OMP3) [Bozkaya J. Chem. Phys. 2011, 135, 224103] and the orbital-optimized MP2.5 (OMP2.5) [Bozkaya and Sherrill J. Chem. Phys. 2014, 141, 204105]. Our results demonstrate that the DF-OMP3 and DF-OMP2.5 methods provide considerably lower computational costs than OMP3 and OMP2.5. Further application results show that the orbital-optimized methods are very helpful for the study of open-shell noncovalent interactions, aromatic bond dissociation energies, and hydrogen transfer reactions. We conclude that the DF-OMP3 and DF-OMP2.5 methods are very promising for molecular systems with challenging electronic structures. PMID:26854993

  15. Structural and optical properties of Ta2O5:Eu3+: Mg2+ or Ca2+ phosphor prepared by molten salt method

    NASA Astrophysics Data System (ADS)

    Verma, Naveen; Mari, Bernabe; Singh, Krishan Chander; Jindal, Jitender; Mollar, Miguel; Rana, Ravi; Pereira, A. L. J.; Manjón, F. J.

    2016-04-01

    Ta2O5:Eu3+: Mg2+ or Ca2+ phosphor materials were prepared by molten salt method using KCl as flux. The X-ray diffraction (XRD) patterns illustrated that the well crystallized Ta2O5:Eu3+: Mg2+ or Ca2+ were formed in the presence of flux under reduced temperature (800 °C) in contrast to conventional solid state method (1200-1500 °C). Scanning electron microscope (SEM) images indicate the achievement of well dispersed particles (hexagonal tablet and rod-like structures). Meanwhile, the photo-luminescent studies demonstrated that Ta2O5 is an efficient host to sensitize europium red emissions. The addition of Mg2+ or Ca2+ as co-dopant enhanced the luminescent intensity of Ta2O5: Eu3+ compound.

  16. Properties and Crystallization Phenomena in Li2Si2O5–Ca5(PO4)3F and Li2Si2O5–Sr5(PO4)3F Glass–Ceramics Via Twofold Internal Crystallization

    PubMed Central

    Rampf, Markus; Dittmer, Marc; Ritzberger, Christian; Schweiger, Marcel; Höland, Wolfram

    2015-01-01

    The combination of specific mechanical, esthetic, and chemical properties is decisive for the application of materials in prosthodontics. Controlled twofold crystallization provides a powerful tool to produce special property combinations for glass–ceramic materials. The present study outlines the potential of precipitating Ca5(PO4)3F as well as Sr5(PO4)3F as minor crystal phases in Li2Si2O5 glass–ceramics. Base glasses with different contents of CaO/SrO, P2O5, and F− were prepared within the glasses of the SiO2–Li2O–K2O–CaO/SrO–Al2O3–P2O5–F system. Preliminary studies of nucleation by means of XRD and scanning electron microscopy (SEM) of the nucleated base glasses revealed X-ray amorphous phase separation phenomena. Qualitative and quantitative crystal phase analyses after crystallization were conducted using XRD in combination with Rietveld refinement. As a main result, a direct proportional relationship between the content of apatite-forming components in the base glasses and the content of apatite in the glass–ceramics was established. The microstructures of the glass–ceramics were investigated using SEM. Microstructural and mechanical properties were found to be dominated by Li2Si2O5 crystals and quite independent of the content of the apatite present in the glass–ceramics. Biaxial strengths of up to 540 MPa were detected. Ca5(PO4)3F and Sr5(PO4)3F influence the translucency of the glass–ceramics and, hence, help to precisely tailor the properties of Li2Si2O5 glass–ceramics. The authors conclude that the twofold crystallization of Li2Si2O5–Ca5(PO4)3F or Li2Si2O5–Sr5(PO4)3F glass–ceramics involves independent solid-state reactions, which can be controlled via the chemical composition of the base glasses. The influence of the minor apatite phase on the optical properties helps to achieve new combinations of features of the glass–ceramics and, hence, displays new potential for dental applications. PMID:26389112

  17. Electrical conduction mechanism in La3Ta0.5Ga5.3Al0.2O14 single crystals.

    PubMed

    Yaokawa, Ritsuko; Aota, Katsumi; Uda, Satoshi

    2013-12-14

    The electrical conduction mechanism in La3Ta0.5Ga5.3Al0.2O14 (LTGA) single crystals was studied by nonstoichiometric defect formation during crystal growth. Since stoichiometric LTGA is not congruent, the single crystal grown from the stoichiometric melt was Ta-poor and Al-rich, where Al atoms were substituted not only in Ga sites but also in Ta sites. The population of the substitutional Al in Ta sites increased with increasing oxygen partial pressure during growth (growth-pO2) in the range from 0.01 to 1 atm. Below 600 °C, substitutional Al atoms in Ta sites were ionized to yield holes, and thus the electrical conductivity of the LTGA crystal depended on temperature and the growth-pO2. The dependence of the electrical conductivity on the growth-pO2 decreased as temperature increased. The temperature rise increases ionic conductivity, for which the dominant carriers are oxygen defects formed by the anion Frenkel reaction. PMID:24396153

  18. Syntheses, X-ray Structures, and Solution Properties of [V(4)O(4){(OCH(2))(3)CCH(3)}(3)(OC(2)H(5))(3)] and [V(4)O(4){(OCH(2))(3)CCH(3)}(2)(OCH(3))(6)]: Examples of New Ligand Coordination Modes.

    PubMed

    Crans, Debbie C.; Jiang, Feilong; Chen, John; Anderson, Oren P.; Miller, Mary M.

    1997-03-12

    Tetranuclear vanadium complexes with alkoxy ligands, [V(4)O(4){&mgr;,&mgr;,&mgr;(3)-(OCH(2))(3)CCH(3)}(2)(OCH(3))(6)] (1) and [V(4)O(4){&mgr;-(OCH(2))(3)CCH(3)}{&mgr;,&mgr;(3)-(OCH(2))(3)CCH(3)}{&mgr;,&mgr;,&mgr;(3)-(OCH(2))(3)CCH(3)}(OR)(3)] (R = C(2)H(5) (2), R = CH(CH(3))(2) (3), R = CH(3) (4)), were synthesized by reacting VO(OR)(3) and H(3)thme (H(3)thme = 1,1,1-tris(hydroxymethyl)ethane) in alcohol. Complex 1 crystallized in the monoclinic space group P2(1)/n with a = 9.646(4) Å, b = 11.502(3) Å, c = 11.960(3) Å, beta = 90.20(3) degrees, V = 1326.9 (7) Å(3), Z = 2 and R (wR(2)) = 0.045 (0.143). Complex 2 also crystallized in the monoclinic space group P2(1)/n with a = 8.290(8) Å, b = 12.237(2) Å, c = 29.118(4) Å, beta = 89.455(9) degrees, V = 2954(3) Å(3), Z = 4, and R(wR(2)) = 0.049 (0.126). Both 1 and 2 are neutral, discrete complexes possessing a common [V(4)O(16)](12)(-) core, which consists of four vanadium(V) atoms chelated by two (1) or three (2) tridentate thme(3)(-) ligands and by six (1) or three (2) RO(-) groups. Compound 1 exhibits a crystallographically required inversion center; in contrast, complex 2 exhibits no crystallographically imposed symmetry, and its three trialkoxy ligands each coordinate differently (one thme(3)(-) is coordinated in a new coordination mode with the oxygens in a terminal, doubly-bridging and triply-bridging mode). Both compounds 1 and 2 maintain their structures in solution, although compound 1 also forms a second minor species upon dissolution. Sequential exchanges of the RO(-) groups in complexes 2 and 3 were investigated by (51)V and (1)H NMR spectroscopy. For example, [V(4)O(4)(thme)(3)(OC(2)H(5))(3)] will react with CH(3)OH to generate [V(4)O(4)(thme)(3)(OCH(3))(3)] (4). These reactions were found to be reversible. The time scale of the alcohol exchange reactions were found to vary depending on the vanadium center that is undergoing the exchange. PMID:11669666

  19. 2,2-Dimethyl-5-[(5-methyl-furan-2-yl)methyl-idene]-1,3-dioxane-4,6-dione.

    PubMed

    Zeng, Wu-Lan

    2011-01-01

    The asymmetric unit of the title compound, C(12)H(12)O(5), contains two independent mol-ecules. In each, the 1,3-dioxane ring adopts an envelope conformation with the dimethyl-substituted C atom forming the flap. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds. PMID:21523135

  20. Phosphate enrichment mechanism in CaO-SiO2-FeO-Fe2O3-P2O5 steelmaking slags with lower binary basicity

    NASA Astrophysics Data System (ADS)

    Li, Jin-yan; Zhang, Mei; Guo, Min; Yang, Xue-min

    2016-05-01

    The addition of silica to steelmaking slags to decrease the binary basicity can promote phosphate enrichment in quenched slag samples. In this study, we experimentally investigated phosphate enrichment behavior in CaO-SiO2-FeO-Fe2O3-P2O5 slags with a P2O5 content of 5.00% and the binary basicity B ranging from 1.0 to 2.0, where the (%Fe t O)/(%CaO) mass percentage ratio was maintained at 0.955. The experimental results are explained by the defined enrichment degree R_{C_2 S - C_3 P} of solid solution 2CaO·SiO2-3CaO·P2O5 (C2S-C3P), where R_{C_2 S - C_3 P} is a component of the developed ion and molecule coexistence theory (IMCT)- N i model for calculating the mass action concentrations N i of structural units in the slags on the basis of the IMCT. The asymmetrically inverse V-shaped relation between phosphate enrichment and binary basicity B was observed to be correlated in the slags under applied two-stage cooling conditions. The maximum content of P2O5 in the C2S-C3P solid solution reached approximately 30.0% when the binary basicity B was controlled at 1.3.

  1. EVALUATION OF NEW 2,2-DIMETHYL-5,5-DIPROPOXYBENZIDINE- AND 3,3-DIPROPOXYBENZIDINE-BASED DIRECT DYE ANALOGS FOR MUTAGENIC ACTIVITY BY USE OF THE SALMONELLA/MAMMALIAN MUTAGENICITY ASSAY

    EPA Science Inventory

    A series of new metallized and unmetallized direct dyes based on benzidine analogs, 2,2'dimethyl-5,5'-dipropoxybenzidine and 3,3'-dipropoxybenzidine, were evaluated for mutagenicity in Salmonella typhimurium strains TA98 and TA100. All of the dyes examined were judged non-mutagen...

  2. Polarization Fatigue in Pb(In0.5Nb0.5)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 Single Crystals

    PubMed Central

    Zhang, Shujun; Luo, Jun; Li, Fei; Meyer, Richard J.; Hackenberger, Wesley; Shrout, Thomas R.

    2010-01-01

    Electric fatigue tests have been conducted on pure and manganese modified Pb(In0.5Nb0.5)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) single crystals along different crystallographic directions. Polarization degradation was observed to suddenly occur above 50–100 bipolar cycles in <110> oriented samples, while <001> oriented samples exhibited almost fatigue free characteristics. The fatigue behavior was investigated as a function of orientation, magnitude of the electric field and manganese dopant. It was found that <001> oriented PIN-PMN-PT crystals were fatigue free, due to its small domain size, being on the order of 1µm. The <110> direction exhibited a strong electrical fatigue behavior due to mechanical degradation. Micro/macro cracks were developed in fatigued <110> oriented single crystals. Fatigue and cracks were the results of strong anisotropic piezoelectric stress and non-180° domain switching, which completely locked the non-180° domains. Furthermore, manganese modified PIN-PMN-PT crystals were found to show improved fatigue behavior due to its enhanced coercive field. PMID:20652090

  3. Crystal structure of 5-(furan-2-yl)-N-phenyl-1,3,4-oxa­diazol-2-amine

    PubMed Central

    Paswan, Santosh; Bharty, Manoj K.; Kumari, Sanyucta; Gupta, Sushil K.; Singh, Nand K.

    2015-01-01

    The title compound, C12H9N3O2, was obtained as a cyclized oxa­diazole derivative from substituted thio­semicarbazide in the presence of manganese(II) acetate. The furan ring is disordered over two orientations, with occupancies of 0.76 (2) and 0.24 (2). The dihedral angles between the central oxa­diazole ring and the pendant phenyl ring and furan ring (major disorder component) are 3.34 (18) and 5.7 (6)°, respectively. A short intra­molecular C—H⋯O contact generates an S(6) ring. In the crystal, inversion dimers linked by pairs of N—H⋯N hydrogen bonds generate R 2 2[8] loops. The dimers are linked by C—H⋯π and π–π inter­actions [range of centroid–centroid distances = 3.291 (2)–3.460 (8) Å], generating a three-dimensional network. PMID:26594577

  4. Antinociceptive Effect of 3-(2,3-Dimethoxyphenyl)-1-(5-methylfuran-2-yl)prop-2-en-1-one in Mice Models of Induced Nociception.

    PubMed

    Ismail, Nur Izzati; Ming-Tatt, Lee; Lajis, Nordin; Akhtar, Muhammad Nadeem; Akira, Ahmad; Perimal, Enoch Kumar; Israf, Daud Ahmad; Sulaiman, Mohd Roslan

    2016-01-01

    The antinociceptive effects produced by intraperitoneal administration of a novel synthetic chalcone, 3-(2,3-dimethoxyphenyl)-1-(5-methylfuran-2-yl)prop-2-en-1-one (DMFP), were investigated in several mouse models of induced nociception. The administration of DMFP (0.1, 0.5, 1.0 and 5.0 mg/kg) produced significant attenuation on the acetic acid-induced abdominal-writhing test. It also produced a significant increase in response latency time in the hot-plate test and a marked reduction in time spent licking the injected paw in both phases of the formalin-induced paw-licking test. In addition, it was also demonstrated that DMFP exhibited significant inhibition of the neurogenic nociceptive response induced by intraplantar injections of capsaicin and glutamate. Moreover, the antinociceptive effect of DMFP in the acetic acid-induced abdominal-writhing test and the hot-plate test was not antagonized by pretreatment with a non-selective opioid receptor antagonist, naloxone. Finally, DMFP did not show any toxic effects and/or mortality in a study of acute toxicity and did not interfere with motor coordination during the Rota-rod test. Our present results show that DMFP exhibits both peripheral and central antinociceptive effects. It was suggested that its peripheral antinociceptive activity is associated with attenuated production and/or release of NO and various pro-inflammatory mediators, while central antinociceptive activity seems to be unrelated to the opioidergic system, but could involve, at least in part, an interaction with the inhibition of capsaicin-sensitive fibers and the glutamatergic system. PMID:27556438

  5. Measurement and Evaluation of Crystallographic Texture in Ti-3Al-2.5V Tubing

    NASA Astrophysics Data System (ADS)

    Zhang, H.; Sheng, Z. M.; Zhang, W. F.; Wang, Y. H.; Yan, M. Q.

    2015-06-01

    Although the texture of Ti alloys is currently evaluated by the pole figure, it can only provide incomplete and qualitative information. In this investigation, the textures of Ti-3Al-2.5V tubing were studied to seek for an appropriate method for evaluating Ti tubing texture. The texture measurement was performed by thinning the tubing chemically into foils and flattening them, followed by x-ray diffraction analysis. A Bruker D8 Advance texture goniometer with Cu Kα radiation was employed for measuring the {0002}, {10-10}, {10-12}, {11-20} and {10-13} incomplete pole figures using the Schultz reflection technique. Based on the pole data, the crystallite orientation distribution function (ODF) was synthesized using TexEval V2.5 software, Bruker AXS GmbH. The texture strengths of the three specimens were compared using pole figures and ODF. It is found that it gives rise to a large error in the texture strength using the pole figure to evaluate texture. The orientation densities of the maxima in ODF and the tilt angle of their basal poles from the normal toward the tangential direction can describe the tubing texture accurately, which can evaluate the tubing mechanical properties. Subsequently, ODF can be used to predict the mechanical properties of batches of tubing.

  6. Ca(2+) signals mediated by Ins(1,4,5)P(3)-gated channels in rat ureteric myocytes.

    PubMed Central

    Boittin, F X; Coussin, F; Morel, J L; Halet, G; Macrez, N; Mironneau, J

    2000-01-01

    Localized Ca(2+)-release signals (puffs) and propagated Ca(2+) waves were characterized in rat ureteric myocytes by confocal microscopy. Ca(2+) puffs were evoked by photorelease of low concentrations of Ins(1,4,5)P(3) from a caged precursor and by low concentrations of acetylcholine; they were also observed spontaneously in Ca(2+)-overloaded myocytes. Ca(2+) puffs showed some variability in amplitude, time course and spatial spread, suggesting that Ins(1,4,5)P(3)-gated channels exist in clusters containing variable numbers of channels and that within these clusters a variable number of channels can be recruited. Immunodetection of Ins(1,4,5)P(3) receptors revealed the existence of several spots of fluorescence in the confocal cell sections, supporting the existence of clusters of Ins(1,4,5)P(3) receptors. Strong Ins(1,4,5)P(3) photorelease and high concentrations of acetylcholine induced Ca(2+) waves that originated from an initiation site and propagated in the whole cell by spatial recruitment of neighbouring Ca(2+)-release sites. Both Ca(2+) puffs and Ca(2+) waves were blocked selectively by intracellular applications of heparin and an anti-Ins(1,4,5)P(3)-receptor antibody, but were unaffected by ryanodine and intracellular application of an anti-ryanodine receptor antibody. mRNAs encoding for the three subtypes of Ins(1,4,5)P(3) receptor and subtype 3 of ryanodine receptor were detected in these myocytes, and the maximal binding capacity of [(3)H]Ins(1,4,5)P(3) was 10- to 12-fold higher than that of [(3)H]ryanodine. These results suggest that Ins(1,4,5)P(3)-gated channels mediate a continuum of Ca(2+) signalling in smooth-muscle cells expressing a high level of Ins(1,4,5)P(3) receptors and no subtypes 1 and 2 of ryanodine receptors. PMID:10861244

  7. The effects of intergroup competition on prosocial behaviors in young children: a comparison of 2.53.5 year-olds with 5.5–6.5 year-olds

    PubMed Central

    Zhu, Yi; Guan, Xian; Li, Yansong

    2015-01-01

    Group-based competition is considered to be a ubiquitous social context in human society. However, little is known about its potential effects on children’s prosocial behaviors. To this end, we designed an experiment in which two age groups (2.53.5 years of age and 5.5–6.5 years of age) engaged in an intergroup competition task where they did a so-called “game” where each child transferred table tennis balls with a spoon from one container to the other. The non-intergroup competition condition was identical to the intergroup competition condition with one exception—no intergroup competition manipulation was involved. Then, they were required to perform two economic games used to measure their prosocial behaviors. We found that under the non-intergroup competition condition, as children aged, their behaviors tended to be more fairness-oriented (such as an increase in egalitarian behaviors). However, under the intergroup competition condition, children at 2.53.5 years of age tended to behave prosocially towards their ingroup members compared with those who are at 5.5–6.5 years of age. The behavioral pattern under the intergroup competition condition reflects strengthening prosocial tendencies driven by the intergroup competition in younger children and simultaneously weakening intergroup competition-driven prosocial tendencies possibly due to the development of fairness-oriented behaviors in older children. Taken together, these results point to the importance of considering the effects of competitive contexts on children’s social behaviors and may have important implications for further research on the role of competitive contexts in the development of human prosocial behaviors. PMID:25729357

  8. The effects of intergroup competition on prosocial behaviors in young children: a comparison of 2.5-3.5 year-olds with 5.5-6.5 year-olds.

    PubMed

    Zhu, Yi; Guan, Xian; Li, Yansong

    2015-01-01

    Group-based competition is considered to be a ubiquitous social context in human society. However, little is known about its potential effects on children's prosocial behaviors. To this end, we designed an experiment in which two age groups (2.5-3.5 years of age and 5.5-6.5 years of age) engaged in an intergroup competition task where they did a so-called "game" where each child transferred table tennis balls with a spoon from one container to the other. The non-intergroup competition condition was identical to the intergroup competition condition with one exception-no intergroup competition manipulation was involved. Then, they were required to perform two economic games used to measure their prosocial behaviors. We found that under the non-intergroup competition condition, as children aged, their behaviors tended to be more fairness-oriented (such as an increase in egalitarian behaviors). However, under the intergroup competition condition, children at 2.5-3.5 years of age tended to behave prosocially towards their ingroup members compared with those who are at 5.5-6.5 years of age. The behavioral pattern under the intergroup competition condition reflects strengthening prosocial tendencies driven by the intergroup competition in younger children and simultaneously weakening intergroup competition-driven prosocial tendencies possibly due to the development of fairness-oriented behaviors in older children. Taken together, these results point to the importance of considering the effects of competitive contexts on children's social behaviors and may have important implications for further research on the role of competitive contexts in the development of human prosocial behaviors. PMID:25729357

  9. (E)-1-(2,5-Dichloro-3-thien­yl)-3-(3,4-dimeth­oxy­phen­yl)prop-2-en-1-one

    PubMed Central

    Harrison, William T. A.; Chidan Kumar, C. S.; Yathirajan, H. S.; Mayekar, A. N.; Narayana, B.

    2010-01-01

    In the title compound, C15H12Cl2O3S, the prop-2-en-1-one (enone) fragment is almost planar [C—C—C—O = 2.2 (4)°] and it subtends dihedral angles of 11.9 (2) and 11.0 (2)° with the thio­phene and benzene rings, respectively. The dihedral angle between the aromatic rings is 3.47 (16)°. In the crystal, weak C—H⋯O and C—H⋯Cl inter­actions link the mol­ecules, leading to R 2 2(14), R 2 2(24) and C(11) supra­molecular motifs occurring within the three-dimensional network. Weak aromatic π–π stacking [centroid–centroid separations = 3.6823 (15) and 3.8722 (15) Å] may also help to consolidate the packing. PMID:21587480

  10. Lattice distortion and stripelike antiferromagnetic order in Ca10(Pt3As8)(Fe2As2)5

    SciTech Connect

    Sapkota, Aashish; Tucker, Gregory S; Ramazanoglu, Mehmet; Tian, Wei; Ni, N; Cava, R J; McQueeney, Robert J; Goldman, Alan I; Kreyssig, Andreas

    2014-09-01

    Ca10(Pt3As8)(Fe2As2)5 is the parent compound for a class of Fe-based high-temperature superconductors where superconductivity with transition temperatures up to 30 K can be introduced by partial element substitution. We present a combined high-resolution high-energy x-ray diffraction and elastic neutron scattering study on a Ca10(Pt3As8)(Fe2As2)5 single crystal. This study reveals the microscopic nature of two distinct and continuous phase transitions to be very similar to other Fe-based high-temperature superconductors: an orthorhombic distortion of the high-temperature tetragonal Fe-As lattice below TS=110(2) K followed by stripelike antiferromagnetic ordering of the Fe moments below TN=96(2) K. These findings demonstrate that major features of the Fe-based high-temperature superconductors are very robust against variations in chemical constitution as well as structural imperfection of the layers separating the Fe-As layers from each other and confirms that the Fe-As layers primarily determine the physics in this class of material.

  11. Night-time chemistry above London: measurements of NO3 and N2O5 from the BT Tower

    NASA Astrophysics Data System (ADS)

    Benton, A. K.; Langridge, J. M.; Ball, S. M.; Bloss, W. J.; Dall'Osto, M.; Nemitz, E.; Harrison, R. M.; Jones, R. L.

    2010-10-01

    Broadband cavity enhanced absorption spectroscopy (BBCEAS) has been used to measure the sum of concentrations of NO3 and N2O5 from the BT (telecommunications) Tower 160 m above street level in central London during the REPARTEE II campaign in October and November 2007. Substantial variability was observed in these night-time nitrogen compounds: peak NO3+N2O5 mixing ratios reached 800 pptv, whereas the mean night-time NO3+N2O5 was approximately 30 pptv. Additionally, [NO3+N2O5] showed negative correlations with [NO] and [NO2] and a positive correlation with [O3]. Co-measurements of temperature and NO2 from the BT Tower were used to calculate the equilibrium partitioning between NO3 and N2O5 which was always found to strongly favour N2O5 (NO3/N2O5=0.01 to 0.04). Two methods are used to calculate the lifetimes for NO3 and N2O5, the results being compared and discussed in terms of the implications for the night-time oxidation of nitrogen oxides and the night-time sinks for NOy.

  12. 2,3,6-/3,4,5-Trimethyl substituted diaryl carotenoid derivatives (Chlorobiaceae) in petroleums of the Belarussian Pripyat River Basin

    USGS Publications Warehouse

    Clifford, D.J.; Clayton, J.L.; Sinninghe, Damste J.S.

    1998-01-01

    Degradation products of the 2,3,6-/3,4,5-trimethyl substituted analog of isorenieratene were characterized in Belarussian petroleums. Devonian oils of low maturity were found to contain high concentrations (e.g., 35 mg/g) of C40 diaryl isoprenoids (2,3,6-/3,4,5-trimethyl substitution) along with an abundance of maturation-related compounds. A maturation scheme for diaryl carotenoid (2,3,6-/3,4,5-trimethyl substitution) precursors was proposed. Diaryl isoprenoids and aryl isoprenoid (2,3,6- and 3,4,5-trimethyl substitutions) contents were found to decrease as a function of maturity. Maturity parameters based on (i) the ratio of two specific C15 aryl isoprenoids and (ii) the ratio of C15 (2,3,6) aryl isoprenoids to C40 diaryl isoprenoids (2,3,6-/3,4,5) were proposed.Degradation products of the 2,3,6-/3,4,5-trimethyl substituted analog of isorenieratene were characterized in Belarussian petroleums. Devonian oils of low maturity were found to contain high concentrations (e.g., 35 mg/g) of C40 diaryl isoprenoids (2,3,6-/3,4,5-trimethyl substitution) along with an abundance of maturation-related compounds. A maturation scheme for diaryl carotenoid (2,3,6-/3,4,5-trimethyl substitution) precursors was proposed. Diaryl isoprenoids and aryl isoprenoid (2,3,6- and 3,4,5-trimethyl substitutions) contents were found to decrease as a function of maturity. Maturity parameters based on (i) the ratio of two specific C15 aryl isoprenoids and (ii) the ratio of C15 (2,3,6) aryl isoprenoids to C40 diaryl isoprenoids (2,3,6-/3,4,5) were proposed.

  13. All-cis 1,2,3,4,5,6-hexafluorocyclohexane is a facially polarized cyclohexane

    NASA Astrophysics Data System (ADS)

    Keddie, Neil S.; Slawin, Alexandra M. Z.; Lebl, Tomas; Philp, Douglas; O'Hagan, David

    2015-06-01

    The highest-energy stereoisomer of 1,2,3,4,5,6-hexafluorocyclohexane, in which all of the fluorines are ‘up’, is prepared in a 12-step protocol. The molecule adopts a classic chair conformation with alternate C-F bonds aligned triaxially, clustering three highly electronegative fluorine atoms in close proximity. This generates a cyclohexane with a high molecular dipole (μ = 6.2 D), unusual in an otherwise aliphatic compound. X-ray analysis indicates that the intramolecular Fax···Fax distances (˜2.77 Å) are longer than the vicinal Fax···Feq­ distances (˜2.73 Å) suggesting a tension stabilizing the chair conformation. In the solid state the molecules pack in an orientation consistent with electrostatic ordering. Our synthesis of this highest-energy isomer demonstrates the properties that accompany the placement of axial fluorines on a cyclohexane and the unusual property of a facially polarized ring in organic chemistry. Derivatives have potential as new motifs for the design of functional organic molecules or for applications in supramolecular chemistry design.

  14. Glass structure and NIR emission of Er3+ at 1.5 μm in oxyfluoride BaF2-Al2O3-B2O3 glasses

    NASA Astrophysics Data System (ADS)

    Shinozaki, Kenji; Pisarski, Wojciech; Affatigato, Mario; Honma, Tsuyoshi; Komatsu, Takayuki

    2015-12-01

    The glass structure, photoluminescence properties of Eu3+, Judd-Ofelt analysis, and near infrared emissions of Er3+ at 1.5 μm in the oxyfluoride glasses and glass-ceramics of 1Eu2O3- or 1Er2O3-doped 50BaF2-xAl2O3-(50 - x)B2O3 (x = 0-25 mol%) were investigated. It was clarified on the ground of Raman scattering spectroscopy and F1s and O1s XPS measurements that the glass with no Al2O3 (1Er2O3-50BaF2-50B2O3) is composed of BO3, BO2F and BO3F units with F-Ba bonds. The glasses with 25Al2O3 (1Er2O3-50BaF2-25Al2O3-25B2O3) is mainly composed of BO3- and Al(O,F)x units. Existence of non-bridging oxygen was not detected by O1s-XPS spectra. It was proposed that these structures are largely affected on crystallization behavior, e.g., the glass with no Al2O3 forms BaF2 and β-BaB2O4 due to Ba-F bonds and the glass with 25Al2O3 forms BaAlBO3F2 because the glass structure composed of BO3 and Al(O,F) units is similar to the BaAlBO3F2 crystal structure. Judd-Ofelt parameters of Er3+ and Eu3+ in the glasses showed almost the same values in Ω4 and Ω6 for each glass, on the other hand Ω2 decreased with addition of Al2O3. The emission spectra of Er3+ at 1.5 μm in the glasses and glass-ceramics with BaAlBO3F2 crystals showed broad peaks. It is proposed that oxyfluoride glasses and glass-ceramics based on the BaF2-Al2O3-B2O3 system have a high potential for optical device applications such as broadband optical amplifiers.

  15. High frequency properties of Fe73.5Cu1Nb3Si13.5B9/Zn0.5Ni0.5Fe2O4 soft magnetic composite with micro-cellular structure

    NASA Astrophysics Data System (ADS)

    Liu, Tong; Wang, MingGang; Zhao, ZhanKui

    2012-12-01

    Soft magnetic composite with micro-cellular structure was prepared by spark plasma sintering (SPS) process with Fe73.5Cu1Nb3Si13.5B9 micron-powders clad by 5wt% Zn0.5Ni0.5Fe2O4 nano-particles. The effect of SPS on the micro structure of the Finemet powder and the micro structure of the composite were studied. It has been found that the as-prepared composite consists of Fe73.5Cu1Nb3Si13.5B9 cells and the cell-wall composed of nano Zn0.5Ni0.5Fe2O4 particles distributing around Fe73.5Cu1Nb3Si13.5B9 cell-body. The composite exhibits low eddy-current loss which is to be resulted by high resistivity of the Zn0.5Ni0.5Fe2O4 cell-wall. The sintered samples were annealed at different temperature and the magnetic properties at different frequency of the annealed samples were measured. It shows that the Zn0.5Ni0.5Fe2O4 cell-wall possesses good thermostability.

  16. Radiative lifetime of the 3s3p exp 3(exp 5 S sub 2 exp 0) metastable level of P(+)

    NASA Technical Reports Server (NTRS)

    Calamai, Anthony G.; Han, Xiaofeng; Parkinson, William H.

    1992-01-01

    The present experimental and theoretical results for the radiative lifetime of the 3s3p exp 3(exp 5 S sub 2 exp 0) metastable level of P(+) encompass an experimental determination of the (exp 5 S sub 2 exp 0) lifetime which represents the first measured lifetime of a low charge-state ion in the Si I sequence. This constitutes a fundamental test of the theoretical methods used to determine transition possibilities for intercombination lines involving this level, and suggests that theoretical techniques used to determine such transition probabilities in low-Z species of the Si I isoelectronic sequence should be reevaluated.

  17. A DFT study of the [3 + 2] versus [4 + 2] cycloaddition reactions of 1,5,6-trimethylpyrazinium-3-olate with methyl methacrylate.

    PubMed

    Domingo, Luis R; Sáez, Jose A; Joule, John A; Rhyman, Lydia; Ramasami, Ponnadurai

    2013-02-15

    The reaction between 1,5,6-trimethylpyrazinium-3-olate and methyl methacrylate (MMA) yielding a lactone-lactam has been studied using the DFT method at the B3LYP/6-31G(d) level. It is concluded that formation of the lactone-lactam is a domino process involving three consecutive reactions: (i) a 1,3-dipolar cycloaddition (13DC) reaction between the pyrazinium-3-olate and MMA yielding a [3 + 2] cycloadduct (CA); (ii) a skeletal rearrangement, which converts the [3 + 2] CA into a formal [4 + 2] CA, possessing a diazabicyclo[2.2.2]octane structure; and finally, (iii) an S(N)2 reaction, promoted by halide anion, with concomitant nucleophilic attack of the created carboxylate anion on an iminium carbon with formation of the lactone ring present in the lactone-lactam. Analysis of the four competitive channels associated with the 13DC reaction indicates that this cycloaddition takes place with complete endo stereoselectivity and 6 regioselectivity, yielding [3 + 2] CA. The subsequent skeletal rearrangement also takes place in an elementary step via a non-concerted mechanism. Electron localization function bonding analysis makes it possible to establish that the bicyclo[2.2.2]octane skeleton present in the lactone-lactam complex structure is not attained via a Diels-Alder reaction between pyrazinium-3-olate and MMA. PMID:23342990

  18. Discovery of pyrido[2,3-d]pyrimidine-based inhibitors of HCV NS5A.

    PubMed

    DeGoey, David A; Betebenner, David A; Grampovnik, David J; Liu, Dachun; Pratt, John K; Tufano, Michael D; He, Wenping; Krishnan, Preethi; Pilot-Matias, Tami J; Marsh, Kennan C; Molla, Akhteruzzaman; Kempf, Dale J; Maring, Clarence J

    2013-06-15

    Efforts to improve the genotype 1a potency and pharmacokinetics of earlier naphthyridine-based HCV NS5A inhibitors resulted in the discovery of a novel series of pyrido[2,3-d]pyrimidine compounds, which displayed potent inhibition of HCV genotypes 1a and 1b in the replicon assay. SAR in this system revealed that the introduction of amides bearing an additional 'E' ring provided compounds with improved potency and pharmacokinetics. Introduction of a chiral center on the amide portion resulted in the observation of a stereochemical dependence for replicon potency and provided a site for the attachment of functional groups useful for improving the solubility of the series. Compound 21 was selected for administration in an HCV-infected chimpanzee. Observation of a robust viral load decline provided positive proof of concept for inhibition of HCV replication in vivo for the compound series. PMID:23642966

  19. A Versatile Synthesis of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB)

    SciTech Connect

    Mitchell, A R; Pagoria, P F; Schmidt, R D; Coburn, M D; Lee, G S; Hsu, P C

    2006-04-06

    A safe and versatile synthesis of high-purity 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) based on vicarious nucleophilic substitution (VNS) chemistry has now been achieved. The starting material can be selected from a variety of inexpensive nitroarenes obtained from commercial suppliers (4-nitroaniline, picric acid) or U.S. stockpiles (ammonium picrate, TNT). The use of picric acid and ammonium picrate (Explosive D) is preferred as both compounds are directly converted to picramide in the presence of ammonium salts (diammonium hydrogen phosphate, ammonium carbamate) in sulfolane at elevated temperature. The picramide resulting from this process is directly converted to TATB using an optimized VNS reaction employing inexpensive hydroxylamine as the nucleophilic aminating reagent. A crucial element in our synthesis is a novel and efficient purification of TATB.

  20. 57Fe Mössbauer study of Lu2Fe3Si5 iron silicide superconductor

    DOE PAGESBeta

    Ma, Xiaoming; Ran, Sheng; Pang, Hua; Li, Fashen; Canfield, Paul C.; Bud'ko, Sergey L.

    2015-08-01

    With the advent of Fe–As based superconductivity it has become important to study how superconductivity manifests itself in details of 57Fe Mössbauer spectroscopy of conventional, Fe-bearing superconductors. The iron-based superconductor Lu2Fe3Si5 has been studied by 57Fe Mössbauer spectroscopy over the temperature range from 4.4 K to room temperature with particular attention to the region close to the superconducting transition temperature (Tc=6.1 K). Consistent with the two crystallographic sites for Fe in this structure, the observed spectra appear to have a pattern consisting of two doublets over the whole temperature range. Furthermore, the value of Debye temperature was estimated from temperaturemore » dependence of the isomer shift and the total spectral area and compared with the specific heat capacity data. Neither abnormal behavior of the hyperfine parameters at or near Tc, nor phonon softening were observed.« less

  1. Naphtho[2,3-c][1,2,5]thiadiazole and 2H-Naphtho[2,3-d][1,2,3]triazole-Containing D-A-π-A Conjugated Organic Dyes for Dye-Sensitized Solar Cells.

    PubMed

    Yen, Yung-Sheng; Ni, Jen-Shyang; Hung, Wei-I; Hsu, Chih-Yu; Chou, Hsien-Hsin; Lin, Jiann-T Suen

    2016-03-01

    Dipolar dyes comprising an arylamine as the electron donor, a cyanoacrylic acid as electron acceptor, and an electron deficient naphtho[2,3-c][1,2,5]thiadiazole (NTD) or naphtho[2,3-d][1,2,3]triazole (NTz) entity in the conjugated spacer, were developed and used as the sensitizers in dye-sensitized solar cells (DSSCs). The introduction of the NTD unit into the molecular frame distinctly narrows the HOMO/LUMO gap with electronic absorption extending to >650 nm. However, significant charge trapping and dye aggregation were found in these dyes. Under standard global AM 1.5 G illumination, the best cell photovoltaic performance achieved 6.37 and 7.53% (∼94% relative to N719-based standard cell) without and with chenodeoxycholic acid (CDCA) coadsorbent, respectively. Without CDCA, the NTz dyes have higher power conversion efficiency (7.23%) than NTD dyes due to less charge trapping, dye aggregation, and better dark current suppression. PMID:26891701

  2. Adenosine deaminase inhibitors. Synthesis and biological evaluation of (+/-)-3,6,7,8-tetrahydro-3-[(2-hydroxyethoxy)methyl]imidazo[4,5-d] [1,3]diazepin-8-ol and some selected C-5 homologues of pentostatin.

    PubMed

    Showalter, H D; Putt, S R; Borondy, P E; Shillis, J L

    1983-10-01

    The synthesis of several analogues of (8R)-3-(2-deoxy-beta-D-erythro- pentofuranosyl)-3,6,7,8-tetrahydroimidazo[4,5-d][1,3]diazepin-8-ol (pentostatin, 1a) is described. Ring closure of 2-amino-1-(5-amino-1H-imidazol-4-yl)ethanone dihydrochloride (3) with triethyl orthoacetate or triethyl orthopropionate gave the C-5 methyl and ethyl ketoaglycons, 6,7-dihydro-5-methylimidazo[4,5-d][1,3]diazepin-8(3H)-one (4b) and 5-ethyl-6,7-dihydroimidazo[4,5-d][1,3]diazepin-8(3H)-one (4c), respectively. Stannic chloride catalyzed condensation of the pertrimethylsilyl derivatives of 4b and 4c with a protected glycosyl halide afforded anomeric mixtures of ketonucleosides 3-(2-deoxy-3,5-di-O-p-toluoyl-beta- and -alpha-D-erythro-pentofuranosyl)-6,7-dihydro-5-methylimidazo[4,5-d] [1,3]diazepin-8(3H)-one (5b and 6b) and 3-(2-deoxy-3,5-di-O-p-toluoyl)-beta- and -alpha-D-erythro-pentofuranosyl)-5-ethyl-6,7-dihydroimidazo[4,5-d]- [1,3]diazepin-8(3H)-one (5c and 6c), respectively. Subsequent separation of the anomers, followed by deprotection and reduction of 5b, 6b, and 5c, afforded the respective 8R and 8S isomers. Stannic chloride catalyzed condensation of pertrimethylsilyl ketoaglycon 4a with 2-(chloromethoxy)-1-(p-toluoyloxy) ethane to give ketonucleoside 6,7-dihydro-3-[[2-(p-toluoyloxy)ethoxy] methyl]imidazo[4,5-d][1,3]diazepin-8(3H)-one (9a) was followed by deprotection to 6,7-dihydro-3[(2-hydroxyethoxy)methyl]imidazo[4,5-d][1,3] diazepin-8(3H)-one (9b) and then reduction to the racemic acyclic pentostatin analogue (+/-)-3,6,7,8-tetrahydro-3-[ (2-hydroxyethoxy)methyl]imidazo[4,5-d][1,3]diazepin-8-ol (2). Ki values for the in vitro adenosine deaminase (EC 3.5.4.4; type I; calf intestinal mucosa) inhibitory activities of 1b, 1c, and 2 were determined to be 1.6 X 10(-8), 1.5 X 10(-6), and 9.8 X 10(-8) M, respectively. When compounds 2 and 9b were tested in combination with vidarabine against herpes simplex virus, type 1, in an HEp-2 plaque reduction assay, only compound 2 was able to

  3. Hippocampal Gene Expression of Deiodinases 2 and 3 and Effects of 3,5-Diiodo-L-Thyronine T2 in Mouse Depression Paradigms

    PubMed Central

    Markova, Natalyia; Chernopiatko, Anton; Schroeter, Careen A.; Malin, Dmitry; Kubatiev, Aslan; Bachurin, Sergey; Costa-Nunes, João; Steinbusch, Harry M. W.; Strekalova, Tatyana

    2013-01-01

    Central thyroid hormone signaling is important in brain function/dysfunction, including affective disorders and depression. In contrast to 3,3′,5-triiodo-L-thyronine (T3), the role of 3,5-diiodo-L-thyronine (T2), which until recently was considered an inactive metabolite of T3, has not been studied in these pathologies. However, both T3 and T2 stimulate mitochondrial respiration, a factor counteracting the pathogenesis of depressive disorder, but the cellular origins in the CNS, mechanisms, and kinetics of the cellular action for these two hormones are distinct and independent of each other. Here, Illumina and RT PCR assays showed that hippocampal gene expression of deiodinases 2 and 3, enzymes involved in thyroid hormone regulation, is increased in resilience to stress-induced depressive syndrome and after antidepressant treatment in mice that might suggest elevated T2 and T3 turnover in these phenotypes. In a separate experiment, bolus administration of T2 at the doses 750 and 1500 mcg/kg but not 250 mcg/kg in naive mice reduced immobility in a two-day tail suspension test in various settings without changing locomotion or anxiety. This demonstrates an antidepressant-like effect of T2 that could be exploited clinically. In a wider context, the current study suggests important central functions of T2, whose biological role only lately is becoming to be elucidated. PMID:24386638

  4. Graphical tensor product reduction scheme for the Lie algebras so(5) = sp(2) , su(3) , and g(2)

    NASA Astrophysics Data System (ADS)

    Vlasii, N. D.; von Rütte, F.; Wiese, U.-J.

    2016-08-01

    We develop in detail a graphical tensor product reduction scheme, first described by Antoine and Speiser, for the simple rank 2 Lie algebras so(5) = sp(2) , su(3) , and g(2) . This leads to an efficient practical method to reduce tensor products of irreducible representations into sums of such representations. For this purpose, the 2-dimensional weight diagram of a given representation is placed in a "landscape" of irreducible representations. We provide both the landscapes and the weight diagrams for a large number of representations for the three simple rank 2 Lie algebras. We also apply the algebraic "girdle" method, which is much less efficient for calculations by hand for moderately large representations. Computer code for reducing tensor products, based on the graphical method, has been developed as well and is available from the authors upon request.

  5. Novel 2,5-disubstituted-1,3,4-oxadiazoles as anti-inflammatory drugs

    PubMed Central

    Durgashivaprasad, Ega; Mathew, Geetha; Sebastian, Sarine; Reddy, S.A Manohar; Mudgal, Jayesh; Nampurath, Gopalan Kutty

    2014-01-01

    Objective: 1,3,4-oxadiazole ring is a versatile moiety with a wide range of pharmacological properties. The present work deals with the synthesis and evaluation of the anti-inflammatory activity of two novel 2,5-disubstituted-1,3,4-oxadiazoles (OSD and OPD). Materials and Methods: Carrageenan-induced rat hind paw edema was employed as an acute model of inflammation. For evaluating sub-acute anti-inflammatory activity, carrageenan-induced inflammation in rat air pouch was employed. Complete Freund's adjuvant-induced arthritis in rats was used as a model of chronic inflammation. To evaluate in vitro anti-inflammatory activity, lipopolysaccharide (LPS)-stimulated RAW264.7 cells were used. Results: OSD (100 mg/kg) reduced carrageen-induced paw edema by 60%, and OPD (100 mg/kg) produced a modest 32.5% reduction. OSD also reduced leukocyte influx and myeloperoxidase in carrageenan-induced rat air pouch model. In complete Freund's adjuvant-induced arthritis model, both OSD and OPD (200 mg/kg for 14 days) reduced paw edema and NO levels. In LPS-stimulated RAW264.7 cells, OSD and OPD inhibited formation of nitric oxide and reactive oxygen species, with OPD showing a better activity in comparison to OSD. Conclusions: OSD was the better of the two compounds in in vivo models of inflammation. The o-phenol substitution at position 2 of oxadiazole ring in OSD may be responsible for its better in vivo anti-inflammatory activity. The ability of the compounds to inhibit LPS-induced pro-inflammatory mediator release suggests an anti-inflammatory mechanism targeting LPS-TLR4-NF-κB signalling pathway, which needs to be explored in detail. The disparate efficacy in vitro and in vivo also requires in-depth evaluation of the pharmacokinetics of these novel oxadiazoles. PMID:25298582

  6. Bulge Growth and Quenching Since Z=2.5 in Candels/3D-HST

    NASA Technical Reports Server (NTRS)

    Lang, Phillip; Wuyts, Stijn; Somerville, Rachel S.; Schreiber, Natascha M. Foerster; Genzel, Reinhard; Bell, Eric F.; Brammer, Gabe; Dekel, Avishai; Faber, Sandra M.; Ferguson, Henry C.; Grogin, Norman A.; Kocevski, Dale D.; Koekemoer, Anton M.; Lutz, Dieter; McGrath, Elizabeth J.; Momcheva, Ivelina; Nelson, Erica J.; Primack, Joel R.; Rosario, David J.; Skelton, Rosalind E.; Tacconi, Linda J.; van Dokkum, Peter G.; Whitaker, Katherine E.

    2014-01-01

    Exploiting the deep high-resolution imaging of all 5 CANDELS fields, and accurate redshift informationprovided by 3D-HST, we investigate the relation between structure and stellar populations fora mass-selected sample of 6764 galaxies above 1010 M, spanning the redshift range 0.5 z 2.5.For the first time, we fit 2-dimensional models comprising a single Sersic fit and two-component (i.e.,bulge + disk) decompositions not only to the H-band light distributions, but also to the stellar massmaps reconstructed from resolved stellar population modeling. We confirm that the increased bulgeprominence among quiescent galaxies, as reported previously based on rest-optical observations, remainsin place when considering the distributions of stellar mass. Moreover, we observe an increaseof the typical Sersic index and bulge-to-total ratio (with median BT reaching 40-50) among starforminggalaxies above 1011 M. Given that quenching for these most massive systems is likely tobe imminent, our findings suggest that significant bulge growth precedes a departure from the starformingmain sequence. We demonstrate that the bulge mass (and ideally knowledge of the bulge andtotal mass) is a more reliable predictor of the star-forming versus quiescent state of a galaxy thanthe total stellar mass. The same trends are predicted by the state-of-the-art semi-analytic model bySomerville et al. In the latter, bulges and black holes grow hand in hand through merging andordisk instabilities, and AGN-feedback shuts off star formation. Further observations will be requiredto pin down star formation quenching mechanisms, but our results imply they must be internal to thegalaxies and closely associated with bulge growth.

  7. Inhibition of Prohormone Convertases PC1/3 and PC2 by 2,5-Dideoxystreptamine Derivatives

    PubMed Central

    Vivoli, Mirella; Caulfield, Thomas R.; Martínez-Mayorga, Karina; Johnson, Alan T.; Jiao, Guan-Sheng

    2012-01-01

    The prohormone convertases PC1/3 and PC2 are eukaryotic serine proteases involved in the proteolytic maturation of peptide hormone precursors and are implicated in a variety of pathological conditions, including obesity, diabetes, and neurodegenerative diseases. In this work, we screened 45 compounds obtained by derivatization of a 2,5-dideoxystreptamine scaffold with guanidinyl and aryl substitutions for convertase inhibition. We identified four promising PC1/3 competitive inhibitors and three PC2 inhibitors that exhibited various inhibition mechanisms (competitive, noncompetitive, and mixed), with sub- and low micromolar inhibitory potency against a fluorogenic substrate. Low micromolar concentrations of certain compounds blocked the processing of the physiological substrate proglucagon. The best PC2 inhibitor effectively inhibited glucagon synthesis, a known PC2-mediated process, in a pancreatic cell line; no cytotoxicity was observed. We also identified compounds that were able to stimulate both 87 kDa PC1/3 and PC2 activity, behavior related to the presence of aryl groups on the dideoxystreptamine scaffold. By contrast, inhibitory activity was associated with the presence of guanidinyl groups. Molecular modeling revealed interactions of the PC1/3 inhibitors with the active site that suggest structural modifications to further enhance potency. In support of kinetic data suggesting that PC2 inhibition probably occurs via an allosteric mechanism, we identified several possible allosteric binding sites using computational searches. It is noteworthy that one compound was found to both inhibit PC2 and stimulate PC1/3. Because glucagon acts in functional opposition to insulin in blood glucose homeostasis, blocking glucagon formation and enhancing proinsulin cleavage with a single compound could represent an attractive therapeutic approach in diabetes. PMID:22169851

  8. Preparation and characterization of Al2O3/Y3Al5O12/ZrO2 ternary hypoeutectic in situ composites by laser rapid solidification

    NASA Astrophysics Data System (ADS)

    Su, Haijun; Zhang, Jun; Tian, Junjie; Liu, Lin; Fu, Hengzhi

    2008-07-01

    The directionally solidified oxide eutectic in situ composite is one of the most promising high-temperature structural materials in oxidizing environments. Pore-free rods and plates of ternary Al2O3/Y3Al5O12 (YAG)/ZrO2 hypoeutectic in situ composites with hypoeutectic composition (71 mol % Al2O3, 17 mol % Y2O3, and 12 mol % ZrO2) are prepared rapidly by the laser zone remelting technique. The hypoeutectic growth and microstructure characteristic of grown crystals are studied using the scanning electron microscopy, x-ray diffraction, and energy dispersive spectroscopy, aiming to understand well the rapid solidification behavior of the ternary oxide system of Al2O3-Y2O3-ZrO2. The rapidly solidified Al2O3/YAG/ZrO2 hypoeutectic shows a refined, interpenetrating, and irregular lamellar structure with a reticular distribution of coarse Al2O3 and yttrium aluminum garnet (YAG) and smaller ZrO2 phases. The fine ZrO2 phases are partially embedded at the Al2O3/YAG interfaces. Moreover, the typical dendrite microstructure similar to the metallic solidification is also observed. The formation of two kinds of microstructures is mainly attributed to the rapid growth during the laser zone remelting and constitutional supercooling. The Al2O3 and YAG phases grow in a typical faceted manner, and the ZrO2 phase presents a weak-faceted growth. The size of the interphase spacing obtained decreases rapidly in increasing the laser scanning rate. The fundamental investigations on the irregular growth mechanisms of the hypoeutectic are suggestive to the comprehension of the complex solidification behavior of the ternary oxide systems.

  9. Evaluation of CaO-SiO2-P2O5-Na2O-Fe2O3 bioglass-ceramics for hyperthermia application.

    PubMed

    Singh, Rajendra Kumar; Srinivasan, A; Kothiyal, G P

    2009-12-01

    Magnetic bioglass ceramics (MBC) are being considered for use as thermoseeds in hyperthermia treatment of cancer. While the bioactivity in MBCs is attributed to the formation of the bone minerals such as crystalline apatite, wollastonite, etc. in a physiological environment, the magnetic property arises from the magnetite [Fe3O4] present in these implant materials. A new set of bioglasses with compositions 41CaO x (52-x)SiO2 x 4P2O5 x xFe2O3 x 3Na2O (2 < or = x < or = 10 mol% Fe2O3) have been prepared by melt quenching method. The as-quenched glasses were then heat treated at 1050 degrees C for 3 h to obtain the glass-ceramics. The structure and microstructure of the samples were characterized using X-ray diffraction and microscopy techniques. X-ray diffraction data revealed the presence of magnetite in the heat treated samples with x > or = 2 mol% Fe2O3. Room temperature magnetic property of the heat treated samples was investigated using a Vibrating Sample Magnetometer. Field scans up to 20 kOe revealed that the glass ceramic samples had a high saturation magnetization and low coercivity. Room temperature hysteresis cycles were also recorded at 500 Oe to ascertain the magnetic properties at clinically amenable field strengths. The area under the magnetic hysteresis loop is a measure of the heat generated by the MBC. The coercivity of the samples is another important factor for hyperthermia applications. The area under the loop increases with an increase in Fe2O3 molar concentration and the. coercivity decreases with an increase in Fe2O3 molar concentration The evolution of magnetic properties in these MBCs as a function of Fe2O3 molar concentration is discussed and correlated with the amount of magnetite present in them. PMID:18560766

  10. Superconducting Bi1.5Pb0.5Sr2Ca2Cu3O(x) ceramics by rapid melt quenching and glass crystallization

    NASA Technical Reports Server (NTRS)

    Bansal, Narottam P.

    1989-01-01

    A glass of nominal Bi(1.5)Pb(0.5)Sr2Ca2Cu3O(x) composition, prepared by rapid quenching of the melt, showed a glass transition temperature of 383 C, crystallization temperature of 446 C, melting temperature of 855 C, and bulk density of 5.69 g/cu cm in air. The activation energy for crystallization of the glass was estimated to be 292kJ/mol from non-isothermal DSC. On heating in oxygen, the glass showed a slow and continuous weight gain starting at approximately 530 C which reached a plateau at approximately 820 C. The weight gained during heating was retained on cooling to ambient conditions indicating an irreversible oxidation step. The influence of annealing conditions on the formation of various phases in the glass has been investigated. The Bi(2)Sr(2)Ca(0)Cu(1)O(6) phase crystallized out first followed by formation of other phases at higher temperatures. The high-T(sub c) phase, isostructural with Bi(2)Sr(2)Ca(2)Cu(3)O(10) was not detected below 840 C, but its fraction increased with the annealing time at 840 C. A sample annealed at 840 C for 243h in air and furnace cooled showed the highest T(sub c)(R=0) of 107.2K and a narrow transition width, delta T(sub c)(10 to 90 percent), of approximately 2 K. The high T(sub c) phase does not seem to crystallize out directly from the glass but is rather produced at high temperature by reaction between the phases formed at lower temperatures. The kinetics of 110K phase formation was sluggish. It appears that the presence of lead helps in the formation and/or stabilization of the 110 K phase.

  11. 2,2-Dimethyl-5-(2-nitro-benzyl-idene)-1,3-dioxane-4,6-dione.

    PubMed

    García-Álvarez, Fernando; Romero, Nancy; Lobato-García, Carlos E; Terán, Joel L; Mendoza, Angel

    2013-01-01

    The asymmetric unit of the title compound, C13H11NO6, contains two mol-ecules in both of which the six-membered 1,3-dioxane-4,6-dione ring shows a screw-boat conformation. The dihedral angles between the best planes through the six-membered rings are 47.8 (2) and 49.8 (2)°. In the crystal, C-H⋯O inter-actions link the mol-ecules, building a supramolecular sheet parallel to the c axis. PMID:23476434

  12. Copper-Mediated [3 + 2] Oxidative Cyclization Reaction of N-Tosylhydrazones and β-Ketoesters: Synthesis of 2,3,5-Trisubstituted Furans.

    PubMed

    Huang, Yubing; Li, Xianwei; Yu, Yue; Zhu, Chuanle; Wu, Wanqing; Jiang, Huanfeng

    2016-06-17

    The first attempt at utilizing N-tosylhydrazones as two-carbon synthons has been successfully achieved, which underwent a copper-mediated [3 + 2] oxidative cyclization reaction to afford 2,3,5-trisubstituted furans in moderate to good yields. The features of this method include inexpensive metal catalyst, readily available substrates, high regioselectivity, and convenient operation. The studies provide important approaches for further exploration of the powerful and diverse reaction abilities of N-tosylhydrazones. PMID:27227374

  13. 77 FR 38799 - Draft Toxicological Review of 1,2,3-, 1,2,4-, and 1,3,5-Trimethylbenzene: In Support of the...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-29

    ...EPA is announcing a 60-day public comment period and a public listening session for the external review draft human health assessment titled ``Toxicological Review of 1,2,3-, 1,2,4-, and 1,3,5- Trimethylbenzene: In Support of Summary Information on the Integrated Risk Information System (IRIS)'' (EPA/635/R-11/012A). The draft assessment was prepared by the National Center for Environmental......

  14. (Z)-Ethyl 2-(2,4-dimethyl­benzyl­idene)-7-methyl-3-oxo-5-phenyl-3,5-dihydro-2H-thia­zolo[3,2-a]pyrimidine-6-carboxyl­ate

    PubMed Central

    Chen, Xiao-Yan; Wang, Han-Chu; Zhang, Qian; Song, Zhi-Jian; Zheng, Fei-Yun

    2012-01-01

    In the title compound, C25H24N2O3S, the dihedral angles between the thia­zole ring and the phenyl and substituted benzene rings are 84.91 (11) and 11.58 (10)°, respectively. The dihydro­pyrimidine ring adopts a flattened boat conformation. The olefinic double bond is in a Z configuration. PMID:22259414

  15. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  16. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  17. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  18. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  19. 47 CFR 2.108 - Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Policy regarding the use of the fixed-satellite... Allocation, Assignment, and Use of Radio Frequencies § 2.108 Policy regarding the use of the fixed-satellite allocations in the 3.6-3.7, 4.5-4.8, and 5.85-5.925 GHz bands. The use of the fixed-satellite allocations...

  20. Application of the novel 5-chloro-2,2,3,3,4,4,5,5-octafluoro-1-pentyl chloroformate derivatizing agent for the direct determination of highly polar water disinfection byproducts.

    PubMed

    Vincenti, Marco; Fasano, Francesca; Valsania, Maria Carmen; Guarda, Pierantonio; Richardson, Susan D

    2010-05-01

    A novel derivatizing agent, 5-chloro-2,2,3,3,4,4,5,5-octafluoropentyl chloroformate (ClOFPCF), was synthesized and tested as a reagent for direct water derivatization of highly polar and hydrophilic analytes. Its analytical performance satisfactorily compared to a perfluorinated chloroformate previously described, namely 2,2,3,3,4,4,5,5-octafluoropentyl chloroformate (OFPCF). The chemical properties (reactivity, selectivity, derivatization products, and their chromatographic and spectral features) for ClOFPCF were investigated using a set of 39 highly polar standard analytes, including, among others, hydroxylamine, malic and succinic acids, resorcinol, hydroxybenzaldehyde, and dihydroxybenzoic acid. Upon derivatization, the analytes were extracted from the aqueous solvent and analyzed by gas chromatography (GC)-mass spectrometry (MS) in the electron-capture negative ionization (ECNI) mode. Positive chemical ionization (PCI)-MS was used for confirming the molecular ions, which were virtually absent in the ECNI mass spectra. ClOFPCF showed good reaction efficiency, good chromatographic and spectroscopic properties (better than with OFPCF), good linearity in calibration curves, and low detection limits (0.3-1 microg/L). A unique feature of the derivatizations with ClOFPCF, and, in general, highly fluorinated chloroformates, is their effectiveness in reacting with carboxylic, hydroxylic, and aminic groups at once, forming multiply-substituted non-polar derivatives that can be easily extracted from the aqueous phase and determined by GC-ECNI-MS. The entire procedure from raw aqueous sample to ready-to-inject hexane solution of the derivatives requires less than 10 min. Another benefit of this procedure is that it produced stable derivatives, with optimal volatility for GC separation, and high electron affinity, which allows their detection as negative ions at trace level. In addition, their mass spectra exhibits chlorine isotopic patterns that clearly indicate how many