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  1. 10 CFR 960.4-2-8 - Human interference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... of the permanent markers and records required by 10 CFR part 60, taking into account site-specific... 10 Energy 4 2010-01-01 2010-01-01 false Human interference. 960.4-2-8 Section 960.4-2-8 Energy... REPOSITORY Postclosure Guidelines § 960.4-2-8 Human interference. The site shall be located such...

  2. 10 CFR 960.4-2-8-1 - Natural resources.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Natural resources. 960.4-2-8-1 Section 960.4-2-8-1 Energy... REPOSITORY Postclosure Guidelines § 960.4-2-8-1 Natural resources. (a) Qualifying condition. This site shall..., scarcity, and technology—the natural resources, including ground water suitable for crop irrigation...

  3. 10 CFR 960.4-2-8-1 - Natural resources.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Natural resources. 960.4-2-8-1 Section 960.4-2-8-1 Energy... REPOSITORY Postclosure Guidelines § 960.4-2-8-1 Natural resources. (a) Qualifying condition. This site shall..., scarcity, and technology—the natural resources, including ground water suitable for crop irrigation...

  4. 10 CFR 960.4-2-8-1 - Natural resources.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Natural resources. 960.4-2-8-1 Section 960.4-2-8-1 Energy... REPOSITORY Postclosure Guidelines § 960.4-2-8-1 Natural resources. (a) Qualifying condition. This site shall..., scarcity, and technology—the natural resources, including ground water suitable for crop irrigation...

  5. 10 CFR 960.4-2-8-1 - Natural resources.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Natural resources. 960.4-2-8-1 Section 960.4-2-8-1 Energy... REPOSITORY Postclosure Guidelines § 960.4-2-8-1 Natural resources. (a) Qualifying condition. This site shall..., scarcity, and technology—the natural resources, including ground water suitable for crop irrigation...

  6. 10 CFR 960.4-2-8 - Human interference.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... of the permanent markers and records required by 10 CFR part 60, taking into account site-specific... 10 Energy 4 2011-01-01 2011-01-01 false Human interference. 960.4-2-8 Section 960.4-2-8 Energy... REPOSITORY Postclosure Guidelines § 960.4-2-8 Human interference. The site shall be located such...

  7. 10 CFR 960.4-2-8 - Human interference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Human interference. 960.4-2-8 Section 960.4-2-8 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE... of the permanent markers and records required by 10 CFR part 60, taking into account...

  8. 10 CFR 960.4-2-8 - Human interference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Human interference. 960.4-2-8 Section 960.4-2-8 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE... of the permanent markers and records required by 10 CFR part 60, taking into account...

  9. 10 CFR 960.4-2-8 - Human interference.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Human interference. 960.4-2-8 Section 960.4-2-8 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES FOR A NUCLEAR WASTE... of the permanent markers and records required by 10 CFR part 60, taking into account...

  10. 2. 8' x 10' enlargement from 4' x 5' negative ...

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

    2. 8' x 10' enlargement from 4' x 5' negative Kevin Kriesel-Coons, Photographer, November 13, 1990 INTERIOR OF HYDRO PLANT, SHOWING CURRENT STATE OF DISREPAIR. - Crosscut Steam Plant, Ancillary Hydro Unit, North side Salt River near Mill Avenue & Washington Street, Tempe, Maricopa County, AZ

  11. 10 CFR 960.4-2-8-2 - Site ownership and control.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Site ownership and control. 960.4-2-8-2 Section 960.4-2-8-2 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES... requirements of 10 CFR part 60, ownership, surface and subsurface rights, and control of access that...

  12. 10 CFR 960.4-2-8-2 - Site ownership and control.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Site ownership and control. 960.4-2-8-2 Section 960.4-2-8-2 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES... requirements of 10 CFR part 60, ownership, surface and subsurface rights, and control of access that...

  13. 10 CFR 960.4-2-8-2 - Site ownership and control.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Site ownership and control. 960.4-2-8-2 Section 960.4-2-8-2 Energy DEPARTMENT OF ENERGY GENERAL GUIDELINES FOR THE PRELIMINARY SCREENING OF POTENTIAL SITES... requirements of 10 CFR part 60, ownership, surface and subsurface rights, and control of access that...

  14. (+/-)-6-tert-butyl-8-hydroxymethyl-2-phenyl-4H-1,3-benzodioxin and 2,2,2',2',6,6'-hexamethyl-8,8'-methylenebis(4H-1,3-benzodioxin).

    PubMed

    Masci, Bernardo; Levi Mortera, Stefano; Varrone, Maurizio; Thuéry, Pierre

    2002-11-01

    Two compounds containing 1,3-benzodioxin groups are reported, namely (+/-)-6-tert-butyl-8-hydroxymethyl-2-phenyl-4H-1,3-benzodioxin, C(19)H(22)O(3), (I), and 2,2,2',2',6,6'-hexamethyl-8,8'-methylenebis(4H-1,3-benzodioxin), C(23)H(28)O(4), (II). The hydroxy groups of neighbouring molecules in (I) are hydrogen bonded to each other, giving rise to double-row chains. The molecule in (II) adopts a 'butterfly' conformation, with the O atoms in distal positions. In both compounds, the dioxin rings are in distorted half-chair conformations. PMID:12415170

  15. 10 CFR 960.4-2-8-2 - Site ownership and control.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... FOR A NUCLEAR WASTE REPOSITORY Postclosure Guidelines § 960.4-2-8-2 Site ownership and control. (a... requirements of 10 CFR part 60, ownership, surface and subsurface rights, and control of access that...

  16. 10 CFR 960.4-2-8-2 - Site ownership and control.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... FOR A NUCLEAR WASTE REPOSITORY Postclosure Guidelines § 960.4-2-8-2 Site ownership and control. (a... requirements of 10 CFR part 60, ownership, surface and subsurface rights, and control of access that...

  17. 2,8-Diazaspiro[4.5]decan-8-yl)pyrimidin-4-amine potent CCR4 antagonists capable of inducing receptor endocytosis.

    PubMed

    Shukla, Lena; Ajram, Laura A; Begg, Malcolm; Evans, Brian; Graves, Rebecca H; Hodgson, Simon T; Lynn, Sean M; Miah, Afjal H; Percy, Jonathan M; Procopiou, Panayiotis A; Richards, Stephen A; Slack, Robert J

    2016-06-10

    A number of potent 2,8-diazaspiro[4.5]decan-8-yl)pyrimidin-4-amine CCR4 antagonists binding to the extracellular allosteric site were synthesised. (R)-N-(2,4-Dichlorobenzyl)-2-(2-(pyrrolidin-2-ylmethyl)-2,8-diazaspiro[4.5]decan-8-yl)pyrimidin-4-amine (R)-(18a) has high affinity in both the [(125)I]-TARC binding assay with a pKi of 8.8, and the [(35)S]-GTPγS functional assay with a pIC50 of 8.1, and high activity in the human whole blood actin polymerisation assay (pA2 = 6.7). The most potent antagonists were also investigated for their ability to induce endocytosis of CCR4 and were found to internalise about 60% of the cell surface receptors, a property which is not commonly shared by small molecule antagonists of chemokine receptors. PMID:26991939

  18. An 8×8/4×4 Adaptive Hadamard Transform Based FME VLSI Architecture for 42K H.264/AVC Encoder

    NASA Astrophysics Data System (ADS)

    Fan, Yibo; Liu, Jialiang; Zhang, Dexue; Zeng, Xiaoyang; Chen, Xinhua

    Fidelity Range Extension (FRExt) (i.e. High Profile) was added to the H.264/AVC recommendation in the second version. One of the features included in FRExt is the Adaptive Block-size Transform (ABT). In order to conform to the FRExt, a Fractional Motion Estimation (FME) architecture is proposed to support the 8×8/4×4 adaptive Hadamard Transform (8×8/4×4 AHT). The 8×8/4×4 AHT circuit contributes to higher throughput and encoding performance. In order to increase the utilization of SATD (Sum of Absolute Transformed Difference) Generator (SG) in unit time, the proposed architecture employs two 8-pel interpolators (IP) to time-share one SG. These two IPs can work in turn to provide the available data continuously to the SG, which increases the data throughput and significantly reduces the cycles that are needed to process one Macroblock. Furthermore, this architecture also exploits the linear feature of Hadamard Transform to generate the quarter-pel SATD. This method could help to shorten the long datapath in the second-step of two-iteration FME algorithm. Finally, experimental results show that this architecture could be used in the applications requiring different performances by adjusting the supported modes and operation frequency. It can support the real-time encoding of the seven-mode 42K@24fps or six-mode 42K@30fps video sequences.

  19. Synthesis of 8-Phenylphenalenones: 2-Hydroxy-8-(4-hydroxyphenyl)-1H-phenalen-1-one from Eichhornia crassipes.

    PubMed

    Ospina, Felipe; Hidalgo, William; Cano, Marisol; Schneider, Bernd; Otálvaro, Felipe

    2016-02-01

    2-Hydroxy-8-(4-hydroxyphenyl)-1H-phenalen-1-one (1), the first reported 8-phenylphenalenone from the roots of Eichhornia crassipes (water hyacinth), was synthesized starting from 2-methoxynaphthalene in 11 steps and with an overall yield of 2%. A cascade Friedel-Crafts/Michael annulation reaction between acryloyl chloride and 2-methoxynaphthalene afforded 9-methoxyperinaphthanone that, after transformation to 9-methoxy-2-(4-methoxyphenyl)-1H-phenalen-1-one by means of standard Suzuki-Miyaura methodology, was subjected to a reductive carbonyl transposition to afford 8-(4-methoxyphenyl)perinaphthanone. Dehydrogenation, epoxidation, and demethylation of the latter afforded 1. PMID:26741281

  20. 10 CFR 960.4-2-8-1 - Natural resources.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... human consumption without treatment, present at or near the site will not be likely to give rise to... resource. (2) Ground water with 10,000 parts per million or more of total dissolved solids along any path.... (5) Potential for foreseeable human activities—such as ground-water withdrawal, extensive...

  1. Synthesis and photophysical properties of 2-aryl-6,8-bis(arylethenyl)-4-methoxyquinolines.

    PubMed

    Khoza, Tebogo Ankie; Maluleka, Marole Maria; Mama, Neliswa; Mphahlele, Malose Jack

    2012-01-01

    Iodine-methanol mediated oxidative-aromatization of 2-aryl-6,8-dibromo-2,3-dihydroquinolin-4(1H)-ones afforded the corresponding 2-aryl-6,8-dibromo-4-methoxy-quinolines in high yield and purity. The isomeric 1-(2-amino-3,5-dibromophenyl)-3-aryl-2-propen-1-ones reacted with iodine in methanol afford in a single pot operation the corresponding 2-aryl-6,8-dibromo-4-methoxyquinoline (major) and 2-aryl-6,8-dibromoquinolin-4(1H)-one (minor) products that were separated in sequence by column chromatography on silica gel. Suzuki-Miyaura cross-coupling of the 6,8-dibromo-4-methoxyquinoline derivatives with excess arylvinylboronic acids afforded the corresponding 2-aryl-6,8-bis(2-arylethenyl)-4-methoxyquinolines. The absorption and fluorescence properties of these compounds were also determined. PMID:23201639

  2. Nqrs Data for C8H5Li2O4.5 [C8H4Li2O4·1/2(H2O)] (Subst. No. 1059)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C8H5Li2O4.5 [C8H4Li2O4·1/2(H2O)] (Subst. No. 1059)

  3. Theoretical investigations of 63Cu2+ orbital Knight shifts for YBa2Cu4O8

    NASA Astrophysics Data System (ADS)

    Kuang, Min-Quan; Wu, Shao-Yi; Zhang, Zhi-Hong; Hu, Xian-Fen

    2015-08-01

    The temperature-independent orbital Knight shifts for the orthorhombic 63Cu2+(1) site in YBa2Cu4O8 (Y124) are investigated by utilizing the high order perturbation formulae of these parameters for a 3d9 ion situated into orthorhombically elongated octahedra. The calculation results are in good agreement with the experimental data. The moderate quasi-axial anisotropies of the Knight shifts are ascribed to the elongation distortion of the four-fold coordinated Cu2+(1) site. The g factors are also theoretically calculated in a uniform way for further experimental verification.

  4. Nqrs Data for C8H8Cl3N3O4S2 (Subst. No. 1087)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C8H8Cl3N3O4S2 (Subst. No. 1087)

  5. Thermally Tunable Dual Emission of the d(8)-d(8) Dimer [Pt2(μ-P2O5(BF2)2)4](4).

    PubMed

    Hofbeck, Thomas; Lam, Yan Choi; Kalbáč, Martin; Záliš, Stanislav; Vlček, Antonín; Yersin, Hartmut

    2016-03-01

    High-resolution fluorescence, phosphorescence, as well as related excitation spectra, and, in particular, the emission decay behavior of solid [Bu4N]4[Pt2(μ-P2O5(BF2)2)4], abbreviated Pt(pop-BF2), have been investigated over a wide temperature range, 1.3-310 K. We focus on the lowest excited states that result from dσ*pσ (5dz(2)-6pz) excitations, i.e., the singlet state S1 (of (1)A2u symmetry in D4h) and the lowest triplet T1, which splits into spin-orbit substates A1u((3)A2u) and Eu((3)A2u). After optical excitation, an unusually slow intersystem crossing (ISC) is observed. As a consequence, the compound shows efficient dual emission, consisting of blue fluorescence and green phosphorescence with an overall emission quantum yield of ∼ 100% over the investigated temperature range. Our investigation sheds light on this extraordinary dual emission behavior, which is unique for a heavy-atom transition metal compound. Direct ISC processes in Pt(pop-BF2) are largely forbidden due to spin-, symmetry-, and Franck-Condon overlap-restrictions and, therefore, the ISC time is as long as 29 ns for T < 100 K. With temperature increase, two different thermally activated pathways, albeit still relatively slow, are promoted by spin-vibronic and vibronic mechanisms, respectively. Thus, distinct temperature dependence of the ISC processes results and, as a consequence, also of the fluorescence/phosphorescence intensity ratio. The phosphorescence lifetime also is temperature-dependent, reflecting the relative population of the triplet T1 substates Eu and A1u. The highly resolved phosphorescence shows a ∼ 220 cm(-1) red shift below 10 K, attributable to zero-field splitting of 40 cm(-1) plus a promoting vibration of 180 cm(-1). PMID:26909653

  6. Inhibitory activities against rice pathogens of 8-hydroxy-2,4,6-octatriynamide from Agrocybe sp.

    PubMed

    Zheng, Yongbiao; Xu, Xiaoping; Wu, Yabin

    2016-03-01

    8-Hydroxy-2,4,6-octatriynamide, a natural polyacetylene with inhibitory activities against rice pathogens, was isolated from the liquid fermentation broth of strain Agrocybe sp. YB2005 during screening for new natural chemical agents to control rice pathogens. 8-hydroxy-2,4,6-octatriynamide was purified by consecutive chromatography over a Cl8 reversed phase silica gel, sephadex LH-20 and silica gel. The chemical structure of 8-hydroxy-2,4,6-octatriynamide was elucidated through spectroscopic analyses, including 1D- and 2D-NMR, ESI mass spectrometry and X-ray single crystal diffraction. Bioassays showed that 8-hydroxy-2,4,6-octatriynamide could significantly inhibit growth of Xanthomonas oryzae with an MIC of 53.1 μM in a 96-well plate and the growth of Rhizoctonia solani at 1.02 mM in a 24-well plate. When rice leaves were inoculated with Magnaporthe grisea and cultured in artificial nutrition liquid containing 0.34 mM 8-hydroxy-2,4,6-octatriynamide, no rice blast was observed. The present study implied that 8-hydroxy-2,4,6-octatriynamide could be a candidate agent against rice pathogens. PMID:26861586

  7. PROCEEDINGS: 1993 SO2 CONTROL SYMPOSIUM - VOLUME 4. SESSIONS 7, 8A, AND 8B

    EPA Science Inventory

    The report documents more than 100 presentations at the 1993 SO2 Control Symposium in Boston, MA, August 24-27, 1993. The presentations covered a wide range of topics: industry's strategies for dealing with Clean Air Act Amendments of 1990, including Phase I strategies, the emiss...

  8. [4+2] cycloaddition reactions between 1,8-disubstituted cyclooctatetraenes and diazo dienophiles: stereoelectronic effects, anticancer properties and application to the synthesis of 7,8-substituted bicyclo[4.2.0]octa-2,4-dienes.

    PubMed

    Grange, Rebecca L; Gallen, Michael J; Schill, Heiko; Johns, Jenny P; Dong, Lin; Parsons, Peter G; Reddell, Paul W; Gordon, Victoria A; Bernhardt, Paul V; Williams, Craig M

    2010-08-01

    A detailed examination of [4+2] cycloaddition reactions between 1,8-disubstituted cyclooctatetraenes and diazo compounds revealed that 4-phenyl-1,2,4-triazole-3,5-dione (PTAD) reacts to form either 2,3- or 3,4-disubstituted adducts. The product distribution can be controlled by modulating the electron density of the cyclooctatetraene. Unprecedented [4+2] cycloadditions between diisopropyl azodicarboxylate (DIAD) and 1,8-disubstituted cyclooctatetraenes are also described and further manipulation of a resulting cycloadduct uncovered a new pathway to the synthetically challenging bicyclo[4.2.0]octa-2,4-diene family. Variation of the substituents resulted in a range of compounds displaying selective action against different human tumour cell types. PMID:20572168

  9. Raman spectroscopic study of the minerals apophyllite-(KF) KCa4Si8O20F·8H2O and apophyllite-(KOH) KCa4Si8O20(F,OH)·8H2O

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; Xi, Yunfei

    2012-11-01

    Raman spectroscopy complimented with infrared spectroscopy has been used to study the variation in molecular structure of two minerals of the apophyllite mineral group, namely apophyllite-(KF) KCa4Si8O20F·8H2O and apophyllite-(KOH) KCa4Si8O20(F,OH)·8H2O. apophyllite-(KF) and apophyllite-(KOH) are different minerals only because of the difference in the percentage of fluorine to hydroxyl ions. The Raman spectra are dominated by a very intense sharp peak at 1059 cm-1. A band at around 846 cm-1 is assigned to the water librational mode. It is proposed that the difference between apophyllite-(KF) and apophyllite-(KOH) is the observation of two Raman bands in the OH stretching region at around 3563 and 3625 cm-1. Multiple water stretching and bending modes are observed showing that there is much variation in hydrogen bonding between water and the silicate surfaces.

  10. Biotransformation of 2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-Hexaazaisowurtzitane (CL-20) by Denitrifying Pseudomonas sp. Strain FA1

    PubMed Central

    Bhushan, Bharat; Paquet, Louise; Spain, Jim C.; Hawari, Jalal

    2003-01-01

    The microbial and enzymatic degradation of a new energetic compound, 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20), is not well understood. Fundamental knowledge about the mechanism of microbial degradation of CL-20 is essential to allow the prediction of its fate in the environment. In the present study, a CL-20-degrading denitrifying strain capable of utilizing CL-20 as the sole nitrogen source, Pseudomonas sp. strain FA1, was isolated from a garden soil. Studies with intact cells showed that aerobic conditions were required for bacterial growth and that anaerobic conditions enhanced CL-20 biotransformation. An enzyme(s) involved in the initial biotransformation of CL-20 was shown to be membrane associated and NADH dependent, and its expression was up-regulated about 2.2-fold in CL-20-induced cells. The rates of CL-20 biotransformation by the resting cells and the membrane-enzyme preparation were 3.2 ± 0.1 nmol h−1 mg of cell biomass−1 and 11.5 ± 0.4 nmol h−1 mg of protein−1, respectively, under anaerobic conditions. In the membrane-enzyme-catalyzed reactions, 2.3 nitrite ions (NO2−), 1.5 molecules of nitrous oxide (N2O), and 1.7 molecules of formic acid (HCOOH) were produced per reacted CL-20 molecule. The membrane-enzyme preparation reduced nitrite to nitrous oxide under anaerobic conditions. A comparative study of native enzymes, deflavoenzymes, and a reconstituted enzyme(s) and their subsequent inhibition by diphenyliodonium revealed that biotransformation of CL-20 is catalyzed by a membrane-associated flavoenzyme. The latter catalyzed an oxygen-sensitive one-electron transfer reaction that caused initial N denitration of CL-20. PMID:12957905

  11. Thermal stability and decomposition mechanism of YBa 2Cu 4O 8

    NASA Astrophysics Data System (ADS)

    Isobe, M.; Suzuki, M.; Ami, T.; Tanaka, M.

    1991-12-01

    The thermal stability and decomposition mechanism of YBa 2Cu 4O 8 were studied by using TG, DTA and X-ray diffractometry. The results clearly show the correspondence between oxygen deficiency and phase stability. The decomposition activation energy at Po 2=1 atm was estimated as 2.18∗10 6J/mol by a kinetic analysis of the thermal gravity. This value indicates that the decomposition is very slow. The time dependence of mass loss could be also estimated at 900°C. We conclude that the Y 2Ba 4Cu 7O 15 phase appears only as an intermediate phase in the YBa 2Cu 4O 8 decomposition process, and that the Y 2Ba 4Cu 7O 15 phase is metastable at Po 2=1 atm.

  12. Prediction of the dielectric strength for c-C4F8 mixtures with CF4, CO2, N2, O2 and air by Boltzmann equation analysis

    NASA Astrophysics Data System (ADS)

    Li, Xingwen; Zhao, Hu; Jia, Shenli; Murphy, Anthony B.

    2014-10-01

    The dielectric strength of c-C4F8, and mixtures of c-C4F8 with CF4, CO2, N2, O2 and air, is studied through solution of the Boltzmann equation. The reduced ionization coefficient α/N and reduced attachment coefficient η/N are calculated, allowing the reduced effective ionization coefficient (α-η)/N and the critical reduced electric field strength (E/N)cr (the reduced electric field for which (α-η)/N = 0), to be determined. A high value of (E/N)cr for an electronegative gas, such as those considered here, indicates good insulating properties. It is found that c-C4F8-N2 and c-C4F8-air have very similar (E/N)cr values, higher than those of the other three mixtures, and superior even to that of pure SF6 for c-C4F8 concentrations above 80%. Comparison of the results obtained for c-C4F8 and c-C4F8-N2 with experimental values from the literature supports the validity of the approach taken here and the parameters used.

  13. Specific heat of YBa sub 2 Cu sub 4 O sub 8 near T sub c

    SciTech Connect

    Willis, J.O. ); Tomeno, Izumi; Miyatake, Takayuki; Itoh, Takao; Tai, Keishi; Koshizuka, Naoki; Tanaka, Shoji . Superconductivity Research Lab.)

    1990-01-01

    Specific heat measurements are reported for a polycrystalline, bulk sample of YBa{sub 2}Cu{sub 4}O{sub 8} prepared at high oxygen pressure. The magnitude of the idealized specific heat jump {triangle}C{sub p}/T at {Tc} (= 80 {plus minus} 0.5K) is 15.5 {plus minus} 2 mJ/K{sup 2}-mole. The transition width {triangle} {Tc} is about 3K. The size of the jump is greatly reduced compared to YBa{sub 2}Cu{sub 3}O{sub 7}. The normal state magnetic susceptibility is somewhat smaller than in YBa{sub 2}Cu{sub 3}O{sub 7} and is temperature dependent. The results suggest a smaller electronic density of states for YBa{sub 2}Cu{sub 4}O{sub 8}. 13 refs., 2 figs., 2 tabs.

  14. Encapsulation of Ni0.8Zn0.2Fe2O4 single crystals in multiwall carbon nanotubes.

    PubMed

    Yahya, Noorhana; Akhtar, Majid Niaz; Koziol, Krzysztof

    2012-10-01

    Magnetic nanoparticles in the hollow region of carbon nanotubes have attraction due to their changing physical electrical and magnetic properties. Nickel zinc ferrite plays an important role in many applications due to its superior magnetic properties. Ni0.8Zn0.2Fe2O4 single crystals were encapsulated in multiwall carbon nanotubes (MWCNTs). The magnetic nano crystals were prepared using a sol-gel self combustion method at the sintering temperature of 750 degrees C and were characterized by XRD, FESEM, TEM and VSM. Initial permeability, Q-factor and relative loss factor were measured by impedance vector network analyzer. XRD patterns were used for the phase identification. FESEM images show morphology and dimensions of the grains of Ni0.8Zn0.2Fe2O4 single crystals and Ni0.8Zn0.2Fe2O4 single crystals in MWCNTs. TEM images were used to investigate single crystal and encapsulation of Ni0.8Zn0.2Fe2O4 single crystals in the MWCNTs. VSM results confirmed super paramagnetic behaviour of encapsulated Ni0.8Zn0.2Fe2O4 single crystals. It was also attributed that encapsulated Ni0.8Zn0.2Fe2O4 single crystals in MWCNTs showed a higher initial permeability (51.608), Q-factor (67.069), and low loss factor (0.0002) as compared to Ni0.8Zn0.2Fe2O4 single crystals. The new encapsulated Ni0.8Zn0.2Fe2O4 single crystals in the MWCNTs may have potential applications in electronic and medical industries. PMID:23421187

  15. Handbook for electron beam welding of 8-inch thick 2-1/4 Cr-1 Mo

    SciTech Connect

    Weber, Charles M.

    1980-08-01

    Purpose of this handbook is to provide a detailed procedure for electron beam welding 8 in. thick SA387 Grade 22 Class 2. Adherence to the procedure will allow others to produce electron beam welds in 8 in. thick 2-1/4 Cr-1 Mo. A justification or description of the effects of alterations of the welding procedure is not included in this report. These effects, along with a metallographic characterization and the mechanical properties produced by the welding procedure, etc., are described in report DOE/10244-10, Electron Beam Welding of 8-in. thick 2-1/4 Cr-1 Mo, Final Report under Contract DE-AC05-77OR10244.

  16. Defeathering of broiler carcasses subjected to delayed scalding 1, 2, 4, and 8 hours after slaughter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    With implementation of farm slaughter, scalding and defeathering could be delayed for a minimum of 2 to 4 h. This research evaluated the potential for delaying scalding and defeathering up to 8 h after slaughter. Following 12 h feed withdrawal broilers were cooped and transported to the pilot plan...

  17. Silicon Surface Modification Using C4F8+O2 Plasma for Nano-Imprint Lithography.

    PubMed

    Lee, Junmyung; Efremov, Alexander; Lee, Jaemin; Yeom, Geun Young; Kwon, Kwang-Ho

    2015-11-01

    The investigation of C4F8+O2 feed gas composition on both plasma parameters and plasma treated silicon surface characteristics was carried out. The combination of plasma diagnostics by Langmuir probes and plasma modeling indicated that an increase in O2 mixing ratio results in monotonically decreasing densities of CF(x) (x = 1-3) radicals as well as in non-monotonic behavior of F atom density. The surface characterization by X-ray photoelectron spectroscopy and contact angle measurements showed that the C4F8+O2 mixtures with less than 60% 02 result in modification of Si surfaces due to the deposition of the FC polymer films while the change of O2 mixing ratio in the range of 30%-60% provides an effective adjustment of the surface characteristics such as surface energy, contact angle, etc. PMID:26726589

  18. Structure and Raman spectra of single crystal La 2(SO 4) 3 · 8H 2O

    NASA Astrophysics Data System (ADS)

    Vanderpool, Richard A.; Khan, Masood A.; Frech, Roger

    1991-05-01

    The room temperature polarized Raman spectra of single-crystal La 2(SO 4) 3 · 8H 2O have been measured in the range 5-4000 cm -1. The internal and external modes,based on a factor group analysis and comparison with Na 2SO 4 and La 2(SO 4) 3 · 9H 2O, have been assigned. A single-crystal X-ray diffraction study shows that La 2(SO 40 3 · 8H 2O crystallizes in the monoclinic space group Pn ( Z = 2) with cell dimensions a = 6.881(2) Å, b = 17.376(4) Å, c = 6.923(2) Å, and β = 92.34 (2)°. The structure was refined to a final R = 0.033 for 2333 observed reflections.

  19. Ba4Ga2Se8: A ternary selenide containing chains and discrete Se22- units

    NASA Astrophysics Data System (ADS)

    Yin, Wenlong; Iyer, Abishek K.; Lin, Xinsong; Mar, Arthur

    2016-05-01

    The ternary selenide Ba4Ga2Se8 has been synthesized by reaction of BaSe, Ga2Se3, and Se at 1023 K. Single-crystal X-ray diffraction analysis revealed a monoclinic structure (space group P21/c, Z=4, a=13.2393(5) Å, b=6.4305(2) Å, c=20.6432(8) Å, β=104.3148(6)°) featuring one-dimensional chains of corner-sharing Ga-centered tetrahedra and discrete Se22- anionic units, with charge-compensating Ba2+ cations located between them. The UV/vis/NIR diffuse reflectance spectrum reveals an optical band gap of 1.63(2) eV, which is consistent with the black color of the crystals and agrees with a calculated gap of 1.51 eV obtained from band structure calculations. The presence of the Se22- units narrows the band gap in Ba4Ga2Se8 relative to other Ba-Ga-Se phases.

  20. Nqrs Data for C8H9KO6 [C8H5KO4·2(H2O)] (Subst. No. 1092)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume A `Substances Containing Ag … C10H15' of Volume 48 `Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III `Condensed Matter'. It contains an extract of Section `3.2 Data tables' of the Chapter `3 Nuclear quadrupole resonance data' providing the NQRS data for C8H9KO6 [C8H5KO4·2(H2O)] (Subst. No. 1092)

  1. Pressure-induced phase transition and superconductivity in YBa2Cu4O8

    NASA Astrophysics Data System (ADS)

    Souliou, S. M.; Subedi, A.; Song, Y. T.; Lin, C. T.; Syassen, K.; Keimer, B.; Le Tacon, M.

    2014-10-01

    We investigate the pressure and temperature dependence of the lattice dynamics of the underdoped, stoichiometric, high-temperature superconductor YBa2Cu4O8 by means of Raman spectroscopy and ab initio calculations. This system undergoes a reversible pressure-induced structural phase transition around 10 GPa to a collapsed orthorhombic structure that is well reproduced by the calculation. The coupling of the B1g-like buckling phonon mode to the electronic continuum is used to probe superconductivity. In the low pressure phase, self-energy effects through the superconducting transition renormalize this phonon, and the amplitude of this renormalization strongly increases with pressure. Whereas our calculation indicates that this mode's coupling to the electronic system is only marginally affected by the structural phase transition, the aforementioned renormalization is completely suppressed in the high pressure phase, demonstrating that under hydrostatic pressures higher than 10 GPa, superconductivity in YBa2Cu4O8 is greatly weakened or obliterated.

  2. 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.

  3. 2,4,6,8-Tetrachlorodibenzothiophene in the Newark Bay Estuary: the likely source and reaction pathways.

    PubMed

    Parette, Robert; Pearson, Wendy N

    2014-09-01

    Historic industrial activity along the Newark Bay Estuary has resulted in pollution from a number of contaminants; one of which is 2,4,6,8-tetrachlorodibenzothiophene (2,4,6,8-TCDT), a unique chemical contaminant whose origins have not been adequately explained. This research demonstrates that the probable source of 2,4,6,8-TCDT was the chlorination of phenol produced via the sulfonation method. Thiophenol, the major impurity in this type of phenol, was likely converted to 2,4,6,8-TCDT through one or more pathways during the production of 2,4-dichlorophenol, 2,4-dichlorophenoxyacetic acid (2,4-D), or 2,4,6-trichlorophenol. From a mass balance standpoint, production of these chemicals at an industrial plant along the Passaic River could account for the 2,4,6,8-TCDT in the Newark Bay Estuary. PMID:24997913

  4. Direct imaging of structural heterogeneity of the melt-spun Fe85.2Si2B8P4Cu0.8 alloy

    NASA Astrophysics Data System (ADS)

    Sato, Kazuhisa; Takenaka, Kana; Makino, Akihiro; Hirotsu, Yoshihiko

    2015-06-01

    A structural heterogeneity of the melt-spun Fe85.2Si2B8P4Cu0.8 alloy has been studied by spherical aberration (Cs) corrected high-resolution transmission electron microscopy. Hollow-cone illumination imaging revealed that the density of coherent scattering regions in the as-quenched Fe85.2Si2B8P4Cu0.8 alloy is much higher than that in the Fe76Si9B10P5 bulk metallic glass. According to the Cs-corrected TEM, crystalline atomic clusters, typically of ˜1 nm in diameter, are densely distributed in an amorphous matrix of Fe85.2Si2B8P4Cu0.8 alloy. Observation of four-fold and six-fold atomic arrangements of these clusters implies existence of Fe clusters with the body centered cubic structure. These Fe clusters must be responsible for the formation of ultrahigh-density α-Fe nanocrystals produced by post-annealing.

  5. Crystal structure of 2-amino-7,7-dimethyl-5-oxo-4-(pyridin-4-yl)-5,6,7,8-tetrahydro-4 H-chromene-3-carbonitrile hemihydrate

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

    The title compound, 2-amino-7,7-dimethyl-5-oxo-4-(pyridin-4-yl)-5,6,7,8-tetrahydro-4 Hchromene-3-carbonitrile was synthesized by multicomponent reaction at room temperature using commercially available urea as inexpensive and environmentally benign organo-catalyst. Its structure was determined by X-ray structure analysis. The crystals are monoclinic, sp. gr. C2/ c, a = 22.010(6), b = 11.0364(10), c = 17.147(4) Å, β = 130.37(4)°, Z = 8, R = 0.0433 for 2377 observed reflections.

  6. Imaging Vortices in YBa2Cu4O8 using a Transmission Electron Microscope

    NASA Astrophysics Data System (ADS)

    Bowell, Charlotte; Loudon, James; Karpinski, Janusz; Midgley, Paul

    2010-03-01

    When magnetic flux penetrates a Type-II superconductor, it does so in the form of superconducting vortices. The study of these vortices can reveal information about the nature of the superconductivity in the material as well as being important for applications. These vortices can be imaged using a transmission electron microscope (TEM), as the electron beam is deflected by the penetrated magnetic flux. This technique was pioneered by Tonomura et al. [1], using a specially adapted microscope. Recently, it has been demonstrated that vortex imaging is also possible on a commercial TEM [2]. Here we present results on the cuprate superconductor YBa2Cu4O8, in which CuO chains running along the crystal b-direction are thought to become superconducting via a proximity effect with the CuO2 planes. A difficulty encountered with the TEM technique is in producing samples thin enough to be electron transparent. A sample, of size 30 μm x 30 μm x 200 nm, was cut from a bulk YBa2Cu4O8 single crystal using focussed ion beam milling. To look into the influence of the CuO chains, Lorentz imaging was used to investigate the vortex configuration and movement in real time, while holography was employed to study the vortex field profile. [1] Harada et al., Nature 360, 51 - 53 (1992) [2] J. C. Loudon and P. A. Midgley, Ultramicroscopy 109: 700-729 (2009)

  7. Ambient pressure synthesis of YBa 2Cu 4O 8 using citrate pyrolysis method

    NASA Astrophysics Data System (ADS)

    Hagiwara, M.; Yamao, T.; Matsuura, M.

    2003-10-01

    Synthetic method of YBa 2Cu 4O 8 (124) under a condition of ambient pressure of O 2 gas using citrate pyrolysis technique is examined in order to improve the reproducibility. A new reaction tube device is designed to ensure complete calcination reaction, and the process from the precursor to 124 phase is traced successively by X-ray diffraction analyses. From the experiments, enough contact of flowing O 2 gas with the precursor, and slow heating rate (1 °C/min) to the optimal reaction temperature 780 °C are suggested to be essential. Long reaction process (for 70 h or more) is necessary for higher purity. A transient mixture state of Y 2Cu 2O 5, BaCO 3 and CuO phases is found to grow up in early stage of the calcination process. This mixture state leads to the formation of final 124 phase with good reproducibility.

  8. Electron beam welding of 8-inch thick 2-1/4 Cr-1 Mo. Final report

    SciTech Connect

    Weber, Charles M.

    1980-08-01

    Electron beam welding procedures were developed and used to make sound welds in 8-inch thick 2-1/4 Cr-1 Mo in the horizontal position. A two-pass technique, one pass from each side, was developed for welding the 8-inch thickness. Techniques for eliminating various weld defects were developed. It was learned that the beam oscillation conditions strongly influenced welding performance. Procedures were developed for hard and soft vacuum operation, but hard vacuum was preferred. Procedures for starting and stopping the welding sequence were developed, along with a repair technique involving re-welding over a plug filled hole. The joint fit-up requirements were determined: a joint mismatch of 3/4 in. was welded, and a joint gap opening of 0.100 in. was welded without alteration of the welding procedure. It was shown that it is not necessary to demagnetize the material for successful welding, but that a special magnetic shield may be needed to protect the electron beam from stray magnetic fields. A demonstration weld failed to meet the NDE requirements of the ASME Boiler and Pressure Vessel Code due to poor base metal quality which adversely affected weld performance. The mechanical properties (hardness, strength, ductility, and impact), and the microstructure of electron beam welded 8-inch thick SA387 Grade 22 Class 2 were determined and appeared to be adequate.

  9. Absolute line intensities in CO2 bands near 4.8 microns

    NASA Technical Reports Server (NTRS)

    Rinsland, C. P.; Benner, D. C.; Devi, V. M.

    1986-01-01

    Absolute intensities for 726 unblended lines in 20 bands of C-12(O-16)2, C-13(O-16)2, O-16C-12O-18, and O-16C-12O-17 in the 4.8-micron spectral region have been determined using a natural sample of ultrahigh-purity CO2. Spectral data were recorded at low pressure (less than 10 torr) and room temperature with the Fourier transform spectrometer in the McMath solar telescope complex on Kitt Peak. Derived vibrational band intensities and coefficients of the F factor for each band were compared to values of the 1982 Air Force Geophysics Laboratory line parameters compilation. The present work fills out the CO2 lines in the 5-micron band systems. Lines in the strongest of these measured bands are being used to infer atmospheric pressure from high-resolution stratospheric spectra recorded during the Spacelab 3 Atmospheric Trace Molecule Spectroscopy experiment.

  10. Synthesis of 2,4,8,10-tetroxaspiro5,5undecane

    NASA Technical Reports Server (NTRS)

    Poshkus, A. C. (Inventor)

    1985-01-01

    Pentaerythritol is converted to its diformal, 2,4,8,10-tetroxaspirol5.5undecane, by heating it to a temperature within the range of about 110 to 150 C, for a period of up to 10 minutes, in the presence of a slight excess of paraformaldehyde and of a catalytic quantity of an acid catalyst such as sulfuric acid. The reaction may be carried out in two steps, by forming first the monoformal, then the diformal. In any case, total reaction time is about 10 minutes, and yield of diformal are greater than 90%. Previous processes require hours or days, and often, tedious operating procedures.

  11. On the magnetic field of OH 231.8+4.2

    NASA Astrophysics Data System (ADS)

    Leal-Ferreira, Marcelo L.; Vlemmings, Wouter H. T.; Diamond, Philip J.; Kemball, Athol; Amiri, Nikta; Desmurs, Jean-François

    2012-08-01

    During the transition from an AGB star to a planetary nebula, a large number of low/intermediate initial mass stars loses its spherical symmetry. The process responsible for that change of morphology is, so far, not well understood. The candidates responsible for shaping these objects are (i) a companion to the star (binary/heavy planet) and its tidal forces, (ii) disk interaction and (iii) magnetic fields - or a combination of these. In particular a binary induced magnetic field is a promising option. To study this we observed the polarization of H2O masers in the known binary pre-Planetary Nebula (pPN) OH231.8+4.2. Our results show a magnetic field B || of ~45 mG is present in the H2O maser region of this pPN.

  12. EFFECT OF PRETREATMENT ON THE BILIARY EXCRETION OF 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (TCDD), 2,3,7,8-TETRACHLORODIBENZOFURAN (TCDF) NAD 3,3'4,4'-TETRACHLOROBIPHENYL (TCB) IN THE RAT

    EPA Science Inventory

    The laterally halogenated chemicals 2,3,7,8-tetrachlorodibenzofuran (TCDF) and 3,3',4,4 1-tetrachlorobiphenyl (TCB) exhibit the same spectrum of toxic effects as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) prototype and most toxic member of the halogenated aromatic hydrocarbon fam...

  13. Thermal properties of PrBa 2Cu 4O 8 prepared at ambient oxygen pressure

    NASA Astrophysics Data System (ADS)

    Yang, H. D.; Lin, C. W.; Lin, J.-Y.; Meen, T. H.; Tsay, H. L.; Huang, J. C.; Sheen, S. R.; Wu, M. K.

    1997-08-01

    Polycrystalline PrBa 2Cu 4O 8 (Pr124) has been prepared at ambient oxygen pressure by nitrite pyrolysis method. Powder x-ray-diffraction patterns show a nearly single R124 phase. Thermogravimetric analysis indicates that its thermal stability is distinct from that of Pr123. Specific heat C has been measured from 0.5 to 40 K, and is very similar to that of Pr123. A maximum of C occurs around 17 K which could be due to a magnetic ordering. Entropy difference ΔS has been calculated from ΔC/ T between Pr124 and Y124. The possible origins of ΔS and the related magnetic properties are discussed. Resistivity ϱ( T) of Pr124 shows a nearly metallic behavior similar to what was observed in Pr124 made by the O 2-HIP technique. The metallic ϱ( T) at low temperatures is of interest and will be discussed.

  14. Symmetric long straight section lattices for 2, 4, and 8 sectors.

    SciTech Connect

    Borland, M.; Accelerator Systems Division

    2009-09-29

    Long straight sections (LSS) are anticipated to be one of the significant changes to the accelerator as part of the APS Renewal. Previously, we developed a lattice with eight LSS that, while workable, would have presented some operational challenges. In the present note, we show improved results for 8LSS, along with new solutions for 4LSS and 2LSS. As before, these lattices are developed by removing the Q2 quadrupoles and moving the Q1 back into its place, permitting a 7.7-m-long insertion device (as judged by the increase in face-to-face distance for the innermost powered quadrupoles). Further increases in length (perhaps 10%) might be possible by removing corrector magnets, but at present we have not considered this in detail.

  15. Nonlinear optical properties of the inorganic metal cluster MO2Ag4S8(PPh3)4

    NASA Astrophysics Data System (ADS)

    Xia, Tie J.; Dogariu, Aristide C.; Mansour, Kamjou; Hagan, David J.; Said, Ali A.; Van Stryland, Eric W.; Shi, Shu

    1996-10-01

    We describe a series of experiments on solutions of the inorganic metal cluster molecules Mo2Ag4S8(PPh3)4 and compare them with data on a suspension of carbon particles in liquid (ink). The optical limiting behavior is measured using both single picosecond 532 nm pulses and nanosecond long trains of these picosecond pulses. Both materials show reduced transmittance for increasing fluence (energy per unit area). We also perform picosecond time-resolved pump-probe measurements. We find that the observed pump-probe data is nearly identical for the metal cluster solution and the carbon particle suspension (CBS), and we conclude that the nonlinear mechanisms are the same for the two materials. Our previous studies have shown that the nonlinear losses are due to scattering and absorption by microplasmas formed after thermionic emission from heated particles of carbon or inorganic clusters.

  16. Stacked charge stripes in the quasi-2D trilayer nickelate La4Ni3O8.

    PubMed

    Zhang, Junjie; Chen, Yu-Sheng; Phelan, D; Zheng, Hong; Norman, M R; Mitchell, J F

    2016-08-01

    The quasi-2D nickelate La4Ni3O8 (La-438), consisting of trilayer networks of square planar Ni ions, is a member of the so-called T' family, which is derived from the Ruddlesden-Popper (R-P) parent compound La4Ni3O10-x by removing two oxygen atoms and rearranging the rock salt layers to fluorite-type layers. Although previous studies on polycrystalline samples have identified a 105-K phase transition with a pronounced electronic and magnetic response but weak lattice character, no consensus on the origin of this transition has been reached. Here, we show using synchrotron X-ray diffraction on high-pO2 floating zone-grown single crystals that this transition is associated with a real space ordering of charge into a quasi-2D charge stripe ground state. The charge stripe superlattice propagation vector, q = (2/3, 0, 1), corresponds with that found in the related 1/3-hole doped single-layer R-P nickelate, La5/3Sr1/3NiO4 (LSNO-1/3; Ni(2.33+)), with orientation at 45° to the Ni-O bonds. The charge stripes in La-438 are weakly correlated along c to form a staggered ABAB stacking that reduces the Coulomb repulsion among the stripes. Surprisingly, however, we find that the charge stripes within each trilayer of La-438 are stacked in phase from one layer to the next, at odds with any simple Coulomb repulsion argument. PMID:27462109

  17. 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.

  18. A novel photoproduct of 2'-deoxyguanosine induced by acetone photosensitization: 8-(2,3,4-trihydroxybutyl)guanine.

    PubMed Central

    Sharma, N D; Davies, R J; Phillips, D R; McCloskey, J A

    1989-01-01

    Acetone photosensitisation of 2'-deoxyguanosine in deaerated aqueous solution gives 8-(2,3,4-trihydroxybutyl)guanine as a major photoproduct. Its structure and that of its tetraacetate have been determined primarily by high resolution 1H NMR and mass spectrometry; a di-isopropylidene derivative has also been prepared. Mechanistic aspects of this novel photochemical transformation are discussed, particularly in relation to the alkaline cleavage of acetone photosensitised DNA at the sites of guanine bases. PMID:2922279

  19. Low sonic boom design and performance of a Mach 2.4/1.8 overland high speed civil transport

    NASA Technical Reports Server (NTRS)

    Morgenstern, John M.

    1992-01-01

    This paper describes the design features of a Douglas Mach 2.4/1.8 Low Sonic Boom High Speed Civil Transport (HSCT) configuration developed for NASA. The configuration is designed to fly over water at Mach 2.4 for highest productivity and economic worth, and fly over land at Mach 1.8 with reduced sonic boom loudness.

  20. High temperature coarsening of Cr2Nb precipitates in Cu-8 Cr-4 Nb alloy

    NASA Technical Reports Server (NTRS)

    Anderson, Kenneth Reed

    1996-01-01

    A new high-temperature-strength, high-conductivity Cu-Cr-Nb alloy with a CrNb ratio of 2:1 was developed to achieve improved performance and durability. The Cu-8 Cr4 Nb alloy studied has demonstrated remarkable thermal and microstructural stability after long exposures at temperatures up to 0.98 T(sub m). This stability was mainly attributed to the slow coarsening kinetics of the Cr2Nb precipitates present in the alloy. At all temperatures, the microstructure consists of a bimodal and sometimes trimodal distribution of strengthening Cr2Nb precipitates, depending on precipitation condition, i.e. from liquid or solid solution, and cooling rates. These precipitates remain in the same size range, i.e. large precipitates of approximately I pm, and small precipitates less dm 300 nm, and effectively pin the grain boundaries thus retaining a fine grain size of 2.7 micro-m after 100 h at 1323 K. (A relatively small number of Cr-rich and Nb-rich particles were also present.) This grain boundary pinning and sluggish coarsening of Cr2Nb particles explain the retention of good mechanical properties after prolonged holding at very high temperatures, e.g., 75% of the original hardness after aging for 100 h at 1273 K. Application of LSW-based coarsening models indicated that the coarsening kinetics of the large precipitates are most likely governed by grain boundary diffsion and, to a lesser extent, volume diffusion mechanisms.

  1. Preparation of YBa 2Cu 4O 8 by a seeding method at ambient pressure

    NASA Astrophysics Data System (ADS)

    Iwai, Yutaka; Noguchi, Mutsumi; Saito, Hiroshi; Takata, Masasuke

    1991-10-01

    A seeding method was applied to the processing method of YBa 2Cu 4O 8 superconducting oxide (124 phase). Seed of the 124 phase was prepared by the HIP process. Seed with 25 wt.% was mixed with the matrix oxide prepared by decomposition of nitric salt. They were pressed and fired at 850°C under oxygen gas flow (1 atm of oxygen partial pressure). After repeating the firing, the 124 single phase was obtained. The sample of this 124 phase exhibited superconductivity at onset temperature of 82 K and zero resistive point at 76 K. From the matrix oxide (unseeded), however, the 124 phase could not be formed under the same conditions.

  2. The BPS spectrum of the 4d {N}=2 SCFT's H 1, H 2, D 4, E 6, E 7, E 8

    NASA Astrophysics Data System (ADS)

    Cecotti, Sergio; Del Zotto, Michele

    2013-06-01

    Extending results of 1112.3984, we show that all rank 1 {N}=2 SCFT's in the sequence H 1, H 2, D 4 E 6, E 7, E 8 have canonical finite BPS chambers containing precisely 2 h(F) = 12(∆ - 1) hypermultiplets. The BPS spectrum of the canonical BPS chambers saturates the conformal central charge c, and satisfies some intriguing numerology.

  3. Thermal conductivity of polycrystalline YBa2Cu4O8 from 10 to 300 K

    NASA Astrophysics Data System (ADS)

    Williams, R. K.; Scarbrough, J. O.; Schmitz, J. M.; Thompson, J. R.

    1998-05-01

    The thermal conductivity λ and electrical resistivity ρ were measured on two samples of the cuprate superconductor YBa2Cu4O8 (Y124). The λ results pass through a maximum at about half of the superconducting transition temperature Tc. The peak λ value is much higher than the peak value for polycrystalline YBa2Cu3O7-δ, Y123, and is about equal to ab plane values for good melt processed Y123. In the normal state most of the λ is due to phonon transport λp and estimates of λp were obtained from the data by making a correction for electronic transport. Phonon-phonon and phonon-electron scattering limit the λp of both Y124 and Y123. In the two compounds, the phonon-phonon scattering is about equally strong, but electron-phonon scattering is considerably weaker in Y124. In the superconducting state, below the λ maximum at Tc/2, λ varies as Tn(n~1/2). This behavior has also been observed in Y123, but is not consistent with phonon scattering theory. The implications of this observation are discussed.

  4. Synthesis, crystal structure, and properties of Mg(x)B50C8 or Mg(x)(B12)4(CBC)2(C2)2 (x = 2.4-4).

    PubMed

    Adasch, Volker; Schroeder, Melanie; Kotzott, Dominik; Ludwig, Thilo; Vojteer, Natascha; Hillebrecht, Harald

    2010-10-01

    Single crystals of a new magnesium boride carbide Mg(x)B(50)C(8) (x = 2.4-4) were synthesized from the elements in a metallic melt using tantalum ampules. Crystals were characterized by single crystal X-ray diffraction and electron microprobe analysis. The variation of the Mg content results from different reaction conditions. The composition Mg(∼3)B(50)C(8) is by far the most favored. It fulfills the electron counting rules of Wade and Longuet-Higgins and thus explains the light-green to yellow transparent color. The structure of Mg(∼3)B(50)C(8) (C2/m, Z = 1, a = 8.9384(12) Å, b = 5.6514(9) Å, c = 9.6021(13) Å, β = 105.86(1)°) consists of B(12) icosahedra. The icosahedra are interconnected by four exohedral B-B bonds to layers. The layers are connected to a three-dimensional covalent network by C(2) and CBC units and further exohedral B-B bonds. The Mg sites are partially occupied. Different site occupation factors cause the various compositions and colors (Mg(2.4)B(50)C(8), brown; Mg(4)B(50)C(8), black). The vibrational spectra show the modes of B(12) icosahedra and C(2) and CBC units as well. Measurements of the microhardness according to Vickers and Knoop revealed remarkably high values of H(V) = 3286 (32.0 GPa) and H(K) = 3165 (31.5 GPa), which exceed the values of B(4)C. Optical spectra reveal a band gap of 2.7 eV for Mg(∼3)B(50)C(8), in agreement to the observed color. This justifies an ionic description, and the formula can be written as (Mg(2+))(3)(B(12)(2-))(4)(CBC(+))(2)(C(2))(2). PMID:20839790

  5. Crystal structures of 4-methyl-2-oxo-2H-chromene-7,8-diyl di­acetate and 4-methyl-2-oxo-2H-chromene-7,8-diyl bis­(pent-4-ynoate)

    PubMed Central

    Akinyemi, Akintunde; Thomas, Courtney; Marsh, Willis; Butcher, Ray J.; Jasinski, Jerry P.; Maynard-Smith, Lystranne A.

    2016-01-01

    In the structures of the two title coumarin derivatives, C14H12O6, (1), and C20H16O6, (2), one with acetate and the other with pent-4-ynoate substituents, both the coumarin rings are almost planar. In (1), both acetate substituents are significantly rotated out of the coumarin plane to minimize steric repulsions. One acetate substituent is disordered over two equivalent conformations, with occupancies of 0.755 (17) and 0.245 (17). In (2), there are two pent-4-ynoate substituents, the C C group of one being disordered over two positions with occupancies of 0.55 (2) and 0.45 (2). One of the pent-4-ynoate substituents is in an extended conformation, while the other is in a bent conformation. In this derivative, the planar part of both pent-4-ynoate substituents deviate from the coumarin plane. The packing of (1) is dominated by π–π stacking involving the coumarin rings and weak C—H⋯O contacts link the parallel stacks in the [101] direction. In contrast, in (2) the packing is dominated by R 2 2(24) hydrogen bonds, involving the acidic sp H atom and the oxo O atom, which link the mol­ecules into centrosymmetric dimers. The bent conformation of one of the pent-4-ynoate substituents prevents the coumarin rings from engaging in π–π stacking. PMID:27308023

  6. 40 CFR 721.10004 - 2-Butenoic acid, 4,4′-[(dibutylstannylene)bis(oxy)]bis[4-oxo-, (2Z,2′Z)-, di-C8-10-isoalkyl...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...-, (2Z,2′Z)-, di-C8-10-isoalkyl esters, C9-rich. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-butenoic acid, 4,4′- bis[4-oxo-,...

  7. 40 CFR 721.10004 - 2-Butenoic acid, 4,4′-[(dibutylstannylene)bis(oxy)]bis[4-oxo-, (2Z,2′Z)-, di-C8-10-isoalkyl...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...-, (2Z,2′Z)-, di-C8-10-isoalkyl esters, C9-rich. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-butenoic acid, 4,4′- bis[4-oxo-,...

  8. 40 CFR 721.10004 - 2-Butenoic acid, 4,4′-[(dibutylstannylene)bis(oxy)]bis[4-oxo-, (2Z,2′Z)-, di-C8-10-isoalkyl...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...-, (2Z,2′Z)-, di-C8-10-isoalkyl esters, C9-rich. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as 2-butenoic acid, 4,4′- bis[4-oxo-,...

  9. Optical Band Gap Study Of Nanocrystalline NiCr0.8Fe1.2O4 Ferrite

    NASA Astrophysics Data System (ADS)

    Prasad, Arun S.; Dolia, S. N.; Dhawan, M. S.; Predeep, P.

    2008-04-01

    Optical energy band gap of nanocrystalline NiCr0.8Fe1.2O4 ferrite have been studied. The nanocrystalline NiCr0.8Fe1.2O4 ferrite have been synthesized using sol-gel technique. X-ray diffraction pattern confirms the formation of spinel structure in single phase and the average particle size is 4 nm. The energy band gap measurements of nanocrystalline NiCr0.8Fe1.2O4 ferrite in pellet form have been carried out by absorption spectra using double beam spectrophotometer. A pellet of nanoparticle ferrite was made under a load of 10 tons. From the analysis of absorption spectra, nanocrystalline NiCr0.8Fe1.2O4 ferrite have been found to have energy band gap of 3.2 eV at room temperature.

  10. CERES ERBE-like Instantaneous TOA Estimates (ES-8) in HDF (CER_ES8_Aqua-FM4_Edition2)

    NASA Technical Reports Server (NTRS)

    Wielicki, Bruce A. (Principal Investigator)

    The ES-8 archival data product contains a 24-hour, single-satellite, instantaneous view of scanner fluxes at the top-of-atmosphere (TOA) reduced from spacecraft altitude unfiltered radiances using Earth Radiation Budget Experiment (ERBE) scanner Inversion algorithms and the ERBE shortwave (SW) and longwave (LW) Angular Distribution Models (ADMs). The ES-8 also includes the total (TOT), SW, LW, and window (WN) channel radiometric data; SW, LW, and WN unfiltered radiance values; and the ERBE scene identification for each measurement. These data are organized according to the CERES 3.3-second scan into 6.6-second records. As long as there is one valid scanner measurement within a record, the ES-8 record will be generated. The following CERES ES8 data sets are currently available: CER_ES8_TRMM-PFM_Edition1 CER_ES8_TRMM-PFM_Edition2 CER_ES8_TRMM-PFM_Transient-Ops2 CER_ES8_Terra-FM1_Edition1 CER_ES8_Terra-FM2_Edition1 CER_ES8_Terra-FM1_Edition2 CER_ES8_Terra-FM2_Edition2 CER_ES8_Aqua-FM3_Edition1 CER_ES8_Aqua-FM4_Edition1 CER_ES8_Aqua-FM3_Edition2 CER_ES8_Aqua-FM4_Edition2 CER_ES8_Aqua-FM3_Edition1-CV CER_ES8_Aqua-FM4_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV CER_ES8_Terra-FM1_Edition1-CV. [Location=GLOBAL] [Temporal_Coverage: Start_Date=1997-12-27; Stop_Date=2005-03-29] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180] [Data_Resolution: Temporal_Resolution=1 day; Temporal_Resolution_Range=Daily - < Weekly].

  11. Human and rat primary hepatocyte CYP1A1 and 1A2 induction with 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, and 2,3,4,7,8-pentachlorodibenzofuran.

    PubMed

    Budinsky, Robert A; LeCluyse, Edward L; Ferguson, Stephen S; Rowlands, J Craig; Simon, Ted

    2010-11-01

    The concentration dose response for aryl hydrocarbon receptor (AHR)-mediated CYP1A1 and CYP1A2 messenger RNA (mRNA) induction and enzyme activity was determined in primary cultures of rat and human hepatocytes for 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,4,7,8-pentachlorodibenzofuran, and 2,3,7,8-tetrachlorodibenzofuran. Eleven different congener concentrations from 0.00001 to 100 nM were used, thus spanning seven orders of magnitude. The Hill model was used to obtain values of EC(x) and maximal response from the individual data sets. No-observed effect concentration values were derived using several statistical methods including Dunnett's test, the Welch-Aspin test, and step-down bilinear regression. Thresholds were estimated using baseline projection methods and a "hockey stick" fitting method. Human hepatocytes were less responsive and less sensitive with respect to CYP1A1 activity and mRNA induction than rats. On the other hand, the human CYP1A2 response was more robust than the response in rats but generally less sensitive. These data allow an evaluation of relative species sensitivities for developing interspecies toxicodynamic adjustment factors, for assessing AHR activation thresholds, and for evaluating relative congener potencies. Overall, these data support the position that humans are less sensitive than rats to these AHR-dependent end points and support the use of a data-derived adjustment factor of 1.0 or less for extrapolating between rats and humans. PMID:20705892

  12. Nevadaite, (Cu2+, Al, V3+)6 [Al8 (PO4)8 F8] (OH 2 (H2O)22, a new phosphate mineral species from the Gold Quarry mine, Carlin, Eureka County, Nevada: description and crystal structure

    USGS Publications Warehouse

    Cooper, M.A.; Hawthorne, F.C.; Roberts, Andrew C.; Foord, E.E.; Erd, Richard C.; Evans, H.T., Jr.; Jensen, M.C.

    2004-01-01

    Nevadaite, (Cu2+, ???, Al, V3+)6 (PO4)8 F8 (OH)2 (H2O)22, is a new supergene mineral species from the Gold Quarry mine, near Carlin, Eureka County, Nevada, U.S.A. Nevadaite forms radiating clusters to 1 mm of prismatic crystals, locally covering surfaces more that 2 cm across; individual crystals are elongate on [001] with a length:width ratio of > 10:1 and a maximum diameter of ???30 ??m. It also occurs as spherules and druses associated with colorless to purple-black fluellite, colorless wavellite, strengitevariscite, acicular maroon-to-red hewettite, and rare anatase, kazakhstanite, tinticite, leucophosphite, torbernite and tyuyamunite. Nevadaite is pale green to turquoise blue with a pale powder-blue streak and a vitreous luster; it does not fluoresce under ultra-violet light. It has no cleavage, a Mohs hardness of ???3, is brittle with a conchoidal fracture, and has measured and calculated densities of 2.54 and 2.55 g/cm3, respectively. Nevadaite is biaxial negative, with ?? 1.540, ?? 1.548, ?? 1.553, 2V(obs.) = 76??, 2V(calc.) = 76??, pleochroic with X pale greenish blue, Y very pale greenish blue, Z blue, and with absorption Z ??? X > Y and orientation X = c, Y = a, Z = b. Nevadaite is orthorhombic, space group P21mn, a 12.123(2), b 18.999(2), c 4.961(1) A?? , V 1142.8(2) A??3, Z = 1, a:b:c = 0.6391:1:0.2611. The strongest seven lines in the X-ray powder-diffraction pattern [d in A??(I)(hkl)] are: 6.077(10)(200), 5.618(9)(130), 9.535(8)(020), 2.983(6)(241), 3.430(4)(041), 2.661(4)(061 , and 1.844(4)(352). A chemical analysis with an electron microprobe gave P2O5 32.54, Al2O3 27.07, V2O3 4.24, Fe2O3 0.07, CuO 9.24, ZnO 0.11, F 9.22, H2O (calc.) 23.48, OH ??? F -3.88, sum 102.09 wt.%; the valence states of V and Fe, and the amount of H2O, were determined by crystal-structure analysis. The resulting empirical formula on the basis of 63.65 anions (including 21.65 H2O pfu) is (CU2+2.00 Zn0.02 V3+0.98 Fe3+0.01 Al1.15)??4.16 Al8 P7.90 O32 [F8.37 (OH 1.63]??10 (H2O

  13. 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

  14. Linear Magnetoresistance of Ca10 Ptn As8 (Fe2 As2)5 (n = 3 and 4)

    NASA Astrophysics Data System (ADS)

    Pan, Jiayun; Karki, Amar; Jin, Rongying

    We report the normal-state magnetoresistance (MR) of superconducting Ca10 Ptn As8(Fe2 As2) 5 (n = 3 and 4) as a function of temperature (50 - 300 K) and magnetic field (0 - 14 Tesla). It is found that MR is positive in a wide temperature range in both transverse (H ⊥ I) and longitudinal (H ∥ I) cases. At a fixed temperature and field, we observe MR (H ⊥ I) > MR (H ∥ I), suggesting spin-orbital coupling in addition to charge-spin interaction. Remarkably, MR shows linear field dependence between 0 and 14 Tesla in a wide temperature range for both n = 3 and 4. The implication of such unusual field dependence of MR will be discussed.

  15. Yegorovite, Na4[Si4O8(OH)4]·7H2O, a new mineral from the Lovozero alkaline pluton, Kola Peninsula

    NASA Astrophysics Data System (ADS)

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

    2010-12-01

    A new mineral, yegorovite, has been identified in the late hydrothermal, low-temperature assemblage of the Palitra hyperalkaline pegmatite at Mt. Kedykverpakhk, Lovozero alkaline pluton, Kola Peninsula, Russia. The mineral is intimately associated with revdite and megacyclite, earlier natrosilite, microcline, and villiaumite. Yegorovite occurs as coarse, usually split prismatic (up to 0.05 × 0.15 × 1 mm) or lamellar (up to 0.05 × 0.7 × 0.8 mm) crystals. Polysynthetic twins and parallel intergrowths are typical. Mineral individuals are combined in bunches or chaotic groups (up to 2 mm); radial-lamellar clusters are less frequent. Yegorovite is colorless, transparent with vitreous luster. Cleavage is perfect parallel to (010) and (001). Fracture is splintery; crystals are readily split into acicular fragments. The Mohs hardness is ˜2. Density is 1.90(2) g/cm3 (meas) and 1.92 g/cm3 (calc). Yegorovite is biaxial (-), with α = 1.474(2), β = 1.479(2), and γ = 1.482(2), 2 V meas > 70°, 2 V calc = 75°. The optical orientation is X ∧ a ˜ 15°, Y = c, Z = b. The IR spectrum is given. The chemical composition determined using an electron microprobe (H2O determined from total deficiency) is (wt %): 23.28 Na2O, 45.45 SiO2, 31.27 H2Ocalc; the total is 100.00. The empirical formula is Na3.98Si4.01O8.02(OH)3.98 · 7.205H2O. The idealized formula is Na4[Si4O8(OH)4] · 7H2O. Yegorovite is monoclinic, space group P21/ c. The unit-cell dimensions are a = 9.874, b= 12.398, c = 14.897 Å, β = 104.68°, V = 1764.3 Å3, Z = 4. The strongest reflections in the X-ray powder pattern ( d, Å ( I, %)([ hkl]) are 7.21(70)[002], 6.21(72)[012, 020], 4.696(44)[022], 4.003(49)[211], 3.734(46)[ bar 2 13], 3.116(100)[024, 040], 2.463(38)[ bar 4 02, bar 2 43]. The crystal structure was studied by single-crystal method, R hkl = 0.0745. Yegorovite is a representative of a new structural type. Its structure consists of single chains of Si tetrahedrons [Si4O8(OH)4]∞ and sixfold polyhedrons

  16. Photoluminescence of Tb 3+ and Mn 2+ activated Ca 8MgGd(PO 4) 7 under vacuum ultraviolet excitation

    NASA Astrophysics Data System (ADS)

    Zhang, Jia; Wang, Yuhua; Huang, Yan

    2011-06-01

    Novel Tb 3+ and Mn 2+ activated Ca 8MgGd(PO 4) 7 phosphors were synthesized by solid-state reaction and their photoluminescence properties in vacuum ultraviolet region were investigated for the first time. It can be observed from the excitation spectra that the host-related absorption band is located around 170 nm, and it overlaps the O 2- → Tb 3+ charge transfer band of Ca 8MgGd(PO 4) 7:Tb 3+ around 161 nm and the 3d 5 → 3d 44s transition band of Ca 8MgGd(PO 4) 7:Mn 2+ near 200 nm. The 4f-4f 5d spin-allowed and spin-forbidden transitions of Tb 3+ are verified to be located at 170-250 and 257-271 nm, respectively. Upon 147 nm excitation, the dominant emission peak intensity of the Ca 8MgGd 0.1(PO 4) 7:0.9Tb 3+ phosphor is about 2.7 times stronger than that of the commercial Zn 2SiO 4:Mn 2+ green phosphor, and the brightness of the former with a short decay time of 2.5 ms is about 98% of the latter's. The Ca 8MgGd(PO 4):Mn 2+ phosphor excited at 147 nm exhibits a deep red emission around 650 nm, which could be attributed to the 4T 1 → 6A 1 transition of Mn 2+, with the CIE index (0.679, 0.321). In a word, the results above indicate that both Tb 3+ and Mn 2+ activated Ca 8MgGd(PO 4) 7 phosphors could be promising for PDP or Hg-free lamp applications.

  17. Characterization of the Antiferromagnetism in Ag(pyz)2(S2O8) with a Two-Dimensional Square Lattice of 4d9 Ag2+ Ions

    SciTech Connect

    Manson, J.; Stone, K; Southerland, H; Lancaster, T; Steele, A; Warter, M; Blundell, S; Pratt, F; Baker, P; et al,

    2009-01-01

    X-ray powder diffraction and magnetic susceptibility measurements show that Ag(pyz){sub 2}(S{sub 2}O{sub 8}) consists of 2D square nets of Ag{sup 2+} ions resulting from the corner-sharing of axially elongated AgN{sub 4}O{sub 2} octahedra and exhibits characteristic 2D antiferromagnetism. Nevertheless, {mu}{sup +}SR measurements indicate that Ag(pyz){sub 2}(S{sub 2}O{sub 8}) undergoes 3D magnetic ordering below 7.8(3) K.

  18. 7-Acetyl­amino-2,4-dimethyl-1,8-naphthyridine

    PubMed Central

    Wang, De-Hui; Yu, Yao-Ming; Chen, Jian-Hua; Fu, Wen-Fu

    2008-01-01

    The air-stable title compound, C12H13N3O, which is of inter­est due to its anti­bacterial properties, is an almost planar mol­ecule in which the ten atoms forming the 1,8-naphthyridine ring have an r.m.s. deviation of 0.03 Å from the least-squares plane calculated using the ten atoms. The plane of the acetyl­amino group is slightly inclined [11.7 (2)°] to the plane of the 1,8-naphthyridine ring. PMID:21200676

  19. A vibrational spectroscopic study of the phosphate mineral whiteite CaMn(++)Mg2Al2(PO4)4(OH)2·8(H2O).

    PubMed

    Frost, Ray L; Scholz, Ricardo; López, Andrés; Xi, Yunfei

    2014-04-24

    Vibrational spectroscopy enables subtle details of the molecular structure of whiteite to be determined. Single crystals of a pure phase from a Brazilian pegmatite were used. The infrared and Raman spectroscopy were applied to compare the molecular structure of whiteite with that of other phosphate minerals. The Raman spectrum of whiteite shows an intense band at 972 cm(-1) assigned to the ν1PO4(3-) symmetric stretching vibrations. The low intensity Raman bands at 1076 and 1173 cm(-1) are assigned to the ν3PO4(3-) antisymmetric stretching modes. The Raman bands at 1266, 1334 and 1368 cm(-1) are assigned to AlOH deformation modes. The infrared band at 967 cm(-1) is ascribed to the PO4(3-)ν1 symmetric stretching vibrational mode. The infrared bands at 1024, 1072, 1089 and 1126 cm(-1) are attributed to the PO4(3-)ν3 antisymmetric stretching vibrations. Raman bands at 553, 571 and 586 cm(-1) are assigned to the ν4 out of plane bending modes of the PO4(3-) unit. Raman bands at 432, 457, 479 and 500 cm(-1) are attributed to the ν2 PO4 and H2PO4 bending modes. In the 2600 to 3800 cm(-1) spectral range, Raman bands for whiteite are found 3426, 3496 and 3552 cm(-1) are assigned to AlOH stretching vibrations. Broad infrared bands are also found at 3186 cm(-1). Raman bands at 2939 and 3220 cm(-1) are assigned to water stretching vibrations. Raman spectroscopy complimented with infrared spectroscopy has enabled aspects of the structure of whiteite to be ascertained and compared with that of other phosphate minerals. PMID:24491665

  20. 8-Methyl-2-oxo-4-(thio­phen-2-yl)-1,2,5,6,7,8-hexa­hydro­quinoline-3-carbonitrile

    PubMed Central

    Asiri, Abdullah M.; Faidallah, Hassan M.; Saqer, Alaa Anwar Ahmad; Ng, Seik Weng; Tiekink, Edward R. T.

    2012-01-01

    In the title compound, C15H14N2OS, the pyridinone ring in the fused-ring system is nearly planar (r.m.s. deviation = 0.011 Å) and the cyclo­hexene ring has a twisted half-boat conformation with the methyl­ene C atom adjacent to the methine C atom deviating by 0.592 (7) Å from the plane defined by the remaining five atoms (r.m.s. deviation = 0.108 Å). The thienyl ring is disordered over two almost coplanar positions of opposite orientation in a 0.649 (4):0.351 (4) ratio, and forms dihedral angles of 51.4 (3) (major component) and 54.2 (3)°, respectively, with the pyridinone ring. In the crystal, inversion-related mol­ecules associate via an eight-membered {⋯HNCO}2 synthon and these are linked into a linear supra­molecular chain along the a axis by weak π–π inter­actions that occur between centrosymmetrically related pyridinone rings [centroid–centroid distance = 3.889 (2) Å]. PMID:22798934

  1. Id3 Controls Cell Death of 2B4+ Virus-Specific CD8+ T Cells in Chronic Viral Infection.

    PubMed

    Menner, Alexandra J; Rauch, Katharina S; Aichele, Peter; Pircher, Hanspeter; Schachtrup, Christian; Schachtrup, Kristina

    2015-09-01

    Sustained Ag persistence in chronic infection results in a deregulated CD8(+) T cell response that is characterized by T cell exhaustion and cell death of Ag-specific CD8(+) T cells. Yet, the underlying transcriptional mechanisms regulating CD8(+) T cell exhaustion and cell death are poorly defined. Using the experimental mouse model of lymphocytic choriomeningitis virus infection, we demonstrate that the transcriptional regulator Id3 controls cell death of virus-specific CD8(+) T cells in chronic infection. By comparing acute and chronic infection, we showed that Id3 (-) virus-specific CD8(+) T cells were less abundant, whereas the absolute numbers of Id3 (+) virus-specific CD8(+) T cells were equal in chronic and acute infection. Phenotypically, Id3 (-) and Id3 (+) cells most prominently differed with regard to expression of the surface receptor 2B4; although Id3 (-) cells were 2B4(+), almost all Id3 (+) cells lacked expression of 2B4. Lineage-tracing experiments showed that cells initially expressing Id3 differentiated into Id3 (-)2B4(+) cells; in turn, these cells were terminally differentiated and highly susceptible to cell death under conditions of persisting Ag. Enforced Id3 expression specifically increased the persistence of 2B4(+) virus-specific CD8(+) T cells by decreasing susceptibility to Fas/Fas ligand-mediated cell death. Thus, our findings reveal that the transcriptional regulator Id3 promotes the survival of virus-specific CD8(+) T cells in chronic infection and suggest that targeting Id3 might be beneficial for preventing cell death of CD8(+) T cells in chronic infection or for promoting cell death of uncontrolled, hyperactive CD8(+) T cells to prevent immunopathology. PMID:26232435

  2. Nqrs Data for K0.8LiNa0.2O4S [LiK0.8Na0.2(SO4)] (Subst. No. 2335)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume B 'Substances Containing C10H16 … Zn' of Volume 48 'Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III 'Condensed Matter'. It contains an extract of Section '3.2 Data tables' of the Chapter '3 Nuclear quadrupole resonance data' providing the NQRS data for K0.8LiNa0.2O4S [LiK0.8Na0.2(SO4)] (Subst. No. 2335)

  3. Summaries of the Sixth Annual JPL Airborne Earth Science Workshop, March 4-8, 1996. Volume 2; AIRSAR Workshop

    NASA Technical Reports Server (NTRS)

    Kim, Yunjin (Editor)

    1996-01-01

    This publication contains the summaries for the Sixth Annual JPL Airborne Earth Science Workshop, held in Pasadena, California, on March 4-8, 1996. The main workshop is divided into two smaller workshops as follows: The Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) workshop, on March 4-6. The summaries for this workshop appear in Volume 1. The Airborne Synthetic Aperture Radar (AIRSAR) workshop, on March 6-8. The summaries for this workshop appear in Volume 2.

  4. 2-Methyl-3-(2-methyl­phen­yl)-4-oxo-3,4-dihydro­quinazolin-8-yl 4-methyl­benzoate

    PubMed Central

    El-Azab, Adel S.; Abdel-Aziz, Alaa A.-M.; Ng, Seik Weng; Tiekink, Edward R. T.

    2012-01-01

    In the title quinazolin-4-one derivative, C24H20N2O3, both the 4-methyl­benzoate [dihedral angle = 83.90 (9)°] and 2-tolyl [87.88 (9)°] groups are almost orthogonal to the central fused ring system. These aryl groups are oriented towards the quinazolin-4-one-bound methyl group. In the crystal, mol­ecules are connected into a three-dimensional architecture by C—H⋯O, C—H⋯π and π–π [ring centroid-to-centroid separation = 3.6458 (13) Å] inter­actions. PMID:22412615

  5. Umbra Ver. 4.8

    SciTech Connect

    Oppel, III, Fred; Hart, Brian; Hart, Derek; Linebarger, John; Rigdon, J. Brian; Wolfenbarger, Paul; Xavier, Patrick; & Gottlieb, Eric

    2010-02-24

    Umbra is a software package that has been in development at Sandia National Laboratories since 1995, under the name Umbra since 1997. Umbra is a software framework written in C++ and Tcl/Tk that has been applied to many operations, primarily dealing with robotics and simulation. Umbra executables are C++ libraries orchestrated with Tcl/Tk scripts. Two major feature upgrades occurred from 4.7 to 4.8 1. System Umbra Module with its own Update Graph within the C++ framework. 2. New terrain graph for fast line-of-sight calculations All else were minor updates such as later versions of Visual Studio, OpenSceneGraph and Boost.

  6. 8-(3-chloro-4-methoxybenzyl)-8H-pyrido[2,3-d]pyrimidin-7-one derivatives as potent and selective phosphodiesterase 5 inhibitors.

    PubMed

    Sakamoto, Toshiaki; Koga, Yuichi; Hikota, Masataka; Matsuki, Kenji; Mochida, Hideki; Kikkawa, Kohei; Fujishige, Kotomi; Kotera, Jun; Omori, Kenji; Morimoto, Hiroshi; Yamada, Koichiro

    2015-04-01

    A novel series of highly selective phosphodiesterase 5 (PDE5) inhibitors was found. 8H-Pyrido[2,3-d]pyrimidin-7-one derivatives bearing an (S)-2-(hydroxymethyl)pyrrolidin-1-yl group at the 2-position and a 3-chloro-4-methoxybenzyl group at the 8-position exhibited potent PDE5 inhibitory activities and high PDE5 selectivity over PDE6. Among the synthesized compounds, the 5-methyl analogue (5b) showed the most potent relaxant effect on isolated rabbit corpus cavernosum with an EC30 value of 0.85 nM. PMID:25754491

  7. 4-Imino-2,7-dimethyl-5,6,7,8-tetra-hydro-4H-1-benzothieno[2,3-d]pyrimidin-3-amine.

    PubMed

    Kalashetti, Mallikarjun B; Fathima, Nikhath; Khan, Ashraf Y; Begum, Noor Shahina; Khazi, I M

    2012-08-01

    In the title compound, C(12)H(16)N(4)S, the fused benzothio-phene and the pyrimidine rings are coplanar [dihedral angle = 1.61 (6)°]. Three C atoms of the cyclohexene ring (at positions 3, 6 and 7) are disordered over two sites with an occupancy ratio of 0.702 (8):0.298 (8). The cyclo-hexene ring in both the major and minor components adopts a half-chair conformation. The crystal structure is stabilized by N-H⋯N and C-H⋯N inter-actions, resulting in the formation of inversion dimers with R(2) (2)(10) and R(2) (2)(12) graph-set motifs. PMID:22904911

  8. 2.8 W end-pumped Yb3+:LiYF4 waveguide laser.

    PubMed

    Bolaños, Western; Starecki, Florent; Braud, Alain; Doualan, Jean-Louis; Moncorgé, Richard; Camy, Patrice

    2013-12-15

    Continuous wave, room temperature laser oscillation around 1 μm is reported for the first time (to our knowledge) from an Yb(3+)-doped fluoride crystalline waveguide fabricated by using the liquid phase epitaxy technique. Maximum slope efficiencies of 76% and 41% were obtained for laser emissions at 994 and 1020 nm, respectively. A maximum output power of 2.8 W was obtained at 1020 nm by pumping around 980 nm with a high-brightness fiber laser in an 87 mm long V-shaped cavity. PMID:24322262

  9. Dodenuclear [Mn(III)(8)Ln(III)(4)] clusters with 2-(hydroxymethyl)pyridine: syntheses, structures, and magnetic properties.

    PubMed

    Sun, Lei; Chen, Hui; Ma, Chengbing; Chen, Changneng

    2015-12-28

    A new family of isostructural Mn/Ln dodenuclear clusters: [Mn8Ln4(O)8(hmp)4(O2CPh)12(NO3)4(PhCO2H)(C2H5OH)] [Ln = La (1), Pr (2), Nd (3), Gd (4), Dy(5), hmpH = 2-(hydroxymethyl)pyridine] have been synthesized by the reaction of Mn(NO3)2 and Ln(NO3)3·6H2O with hmpH and benzoic acid as co-ligands. Compounds 1-5 possess a spindle-shaped core of [MnLn(μ4-O)4(μ3-O)4(μ3-OR)22-OR)8](10+), which is composed of six face-sharing defected cubane units and two square-pyramidal units. The compounds represent the highest nuclearity Mn/Ln clusters with the use of hmpH to date. That the ferromagnetic interactions dominated within complexes 1-4 were suggested by solid-state dc magnetic susceptibility analyses. Compound 4 displays a magnetic-caloric effect (MCE) with 13.94 J kg(-1) K(-1) as the entropy change at 6 K for ΔH = 8 T. Compounds 1 and 5 exhibit an out-of-phase χ''M peak maximum above 2.0 K. Fitting of the ac susceptibility data to an Arrhenius law gives an energy barrier Ueff = 6.88/7.44 K for compounds 1 and 5 respectively. PMID:26581752

  10. Epigenetic regulation of cyclooxygenase-2 by methylation of c8orf4 in pulmonary fibrosis

    PubMed Central

    Evans, Iona C.; Barnes, Josephine L.; Garner, Ian M.; Pearce, David R.; Maher, Toby M.; Shiwen, Xu; Renzoni, Elisabetta A.; Wells, Athol U.; Denton, Christopher P.; Laurent, Geoffrey J.; Abraham, David J.

    2016-01-01

    Fibroblasts derived from the lungs of patients with idiopathic pulmonary fibrosis (IPF) and systemic sclerosis (SSc) produce low levels of prostaglandin (PG) E2, due to a limited capacity to up-regulate cyclooxygenase-2 (COX-2). This deficiency contributes functionally to the fibroproliferative state, however the mechanisms responsible are incompletely understood. In the present study, we examined whether the reduced level of COX-2 mRNA expression observed in fibrotic lung fibroblasts is regulated epigenetically. The DNA methylation inhibitor, 5-aza-2′-deoxycytidine (5AZA) restored COX-2 mRNA expression by fibrotic lung fibroblasts dose dependently. Functionally, this resulted in normalization of fibroblast phenotype in terms of PGE2 production, collagen mRNA expression and sensitivity to apoptosis. COX-2 methylation assessed by bisulfite sequencing and methylation microarrays was not different in fibrotic fibroblasts compared with controls. However, further analysis of the methylation array data identified a transcriptional regulator, chromosome 8 open reading frame 4 (thyroid cancer protein 1, TC-1) (c8orf4), which is hypermethylated and down-regulated in fibrotic fibroblasts compared with controls. siRNA knockdown of c8orf4 in control fibroblasts down-regulated COX-2 and PGE2 production generating a phenotype similar to that observed in fibrotic lung fibroblasts. Chromatin immunoprecipitation demonstrated that c8orf4 regulates COX-2 expression in lung fibroblasts through binding of the proximal promoter. We conclude that the decreased capacity of fibrotic lung fibroblasts to up-regulate COX-2 expression and COX-2-derived PGE2 synthesis is due to an indirect epigenetic mechanism involving hypermethylation of the transcriptional regulator, c8orf4. PMID:26744410

  11. Building block modeling technique: Application to ternary chalcogenide glasses g-Ge2As4Se4 and g-AsGe0.8Se0.8

    NASA Astrophysics Data System (ADS)

    Cai, B.; Zhang, X.; Drabold, D. A.

    2011-03-01

    For some glasses, there are fundamental units, “building blocks” (BBs), that exist in both the liquid and glassy phases. In this Brief Report, we introduce a systematic modeling technique based on the concept of BBs and obtain ab initio models of g-Ge2As4Se4 and g-AsGe0.8Se0.8. The total radial distribution function of g-Ge2As4Se4 shows pleasing agreement with experimental data. The partial pair-correlation functions are predicted for both g-Ge2As4Se4 and g-AsGe0.8Se0.8. The coordination statistics indicate that the “8-N” rule is often violated in these two ternary chalcogenide glasses. The electronic density of states with inverse participation ratio analysis is also reported.

  12. A comparative study of Li8NaV3(P2O7)3(PO4)2 and Li9V3(P2O7)3(PO4)2: Synthesis, structure and electrochemical properties

    NASA Astrophysics Data System (ADS)

    Kuang, Quan; Zhao, Yanming; Dong, Youzhong; Fan, Qinghua; Lin, Xinghao; Liu, Xudong

    2016-02-01

    The energy-density improvement for cathode materials by using the method of occupying the Li site with the lowest formation enthalpy was first presented, and successfully applied to Li9V3(P2O7)3(PO4)2. Herein, the synthesis, structure and electrochemical properties (including both Li extraction and intercalation) of mixed alkali-ion phosphate Li8NaV3(P2O7)3(PO4)2 were comprehensively studied, and compared with its isologue Li9V3(P2O7)3(PO4)2. Both Li8NaV3(P2O7)3(PO4)2 and Li9V3(P2O7)3(PO4)2 were synthesized via an original two-step method for the first time. The sintering temperature of Li8NaV3(P2O7)3(PO4)2 (650 °C) was much lower than that of Li9V3(P2O7)3(PO4)2 (750 °C). The Rietveld structure refinement indicated that Na ions occupied the Li1(2b) site of Li9V3(P2O7)3(PO4)2 as expected, and Li8NaV3(P2O7)3(PO4)2 showed a single charge plateau at 4.4 V vs. Li in the 1st cycle. However, the Na ions migrated from Li1(2b) site after the initial cycle, and the charge plateau at 3.7 V vs. Li reappeared. On the other hand, both Li9V3(P2O7)3(PO4)2 and Li8NaV3(P2O7)3(PO4)2 can deliver a high reversible capacity (∼200 mAh g-1), and reveal excellent cycle and rate performance in 3.0-0.05 V vs. Li. The gentle structure changes along with abundant Li intercalation into the bulks suggested that Li9V3(P2O7)3(PO4)2 and Li8NaV3(P2O7)3(PO4)2 were also promising anode materials for Li-ion batteries.

  13. Discovery of novel 5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-a]pyridine derivatives as γ-secretase modulators (Part 2).

    PubMed

    Takai, Takafumi; Koike, Tatsuki; Nakamura, Minoru; Kajita, Yuichi; Yamashita, Toshiro; Taya, Naohiro; Tsukamoto, Tetsuya; Watanabe, Tomomichi; Murakami, Koji; Igari, Tomoko; Kamata, Makoto

    2016-07-15

    γ-Secretase modulators (GSMs), which lower pathogenic amyloid beta (Aβ) without affecting the production of total Aβ or Notch signal, have emerged as a potential therapeutic agent for Alzheimer's disease (AD). A novel series of 5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-a]pyridine derivatives was discovered and characterized as GSMs. Optimization of substituents at the 8-position of the core scaffold using ligand-lipophilicity efficiency (LLE) as a drug-likeness guideline led to identification of various types of high-LLE GSMs. Phenoxy compound (R)-17 exhibited especially high LLE as well as potent in vivo Aβ42-lowering effect by single administration. Furthermore, multiple oral administration of (R)-17 significantly reduced soluble and insoluble brain Aβ42, and ameliorated cognitive deficit in novel object recognition test (NORT) using Tg2576 mice as an AD model. PMID:27255179

  14. Crystal structure of 2,8-dimethyl-3-chloro-4H-pyrido[1,2-a]pyrimidin-4-one

    NASA Astrophysics Data System (ADS)

    Anthal, S.; Dutt, P.; Satti, N. K.; Kant, R.; Gupta, V. K.

    2014-12-01

    The title compound, 2,8-dimethyl-3-chloro-4H-pyrido[1,2-a]pyrimidin-4-one, (C10H9ClN2O), was synthesized, and its structure was established by spectral analysis and X-ray diffraction studies. There are two independent molecules per asymmetric unit. In both the molecules, the pyrido-pyrimidine moiety is planar with a dihedral angle of 3.53(9)° for molecule A and 1.61(9)° for molecule B. The crystal structure is stabilized by C-H⋯O and C-H⋯Cl hydrogen bonds. The π-π interactions were also observed between the A and B molecules. The pyrido-pyrimidine moiety is not involved in any C-H⋯π contacts.

  15. Fe[S2CNC4H8]2I: A quasi-two-dimensional XY antiferromagnet

    NASA Astrophysics Data System (ADS)

    Harlan, E. W.; Chamberlain, R. V.; DeFotis, G. C.

    1991-04-01

    The magnetic properties of Fe[S2CNC4H8]2I have been studied, the first pentacoordinate Fe(III) system of this type with a cyclic terminal group, rather than an alkyl group, to be examined in detail. The susceptibility of a polycrystalline sample is of Curie-Weiss form above 30 K, with ḡ=2.16 ±0.02 and S=3/2 and with θ=-0.75±1.0 K. Thus the unusual intermediate spin state occurs here as in earlier examples. The susceptibility can be fit quite well down to about 6 K assuming that axial and rhombic crystal field distortions occur, represented by D[Ŝ2z - S(S + 1)/3] and E[Ŝ2x - Ŝ2y] terms in the spin Hamiltonian, and incorporating exchange interactions in a mean-field approximation. Fitted parameters are D/k=9.3± 0.5 K, E/k=-0.6±0.2 K, gx=2.23± 0.05, gy= 2.19 ± 0.05, gz=2.04 ± 0.05, and zJ/k=-0.235 ±0.02 K. At low temperatures the susceptibility exhibits a broad maximum with T(χmax)=3.23± 0.04 K and χmax =0.376±0.004 emu/mol. An antiferromagnetic transition at Tc=2.21±0.01 K is inferred from the position of a maximum in (∂χ/∂T), an ordering temperature in reasonable agreement with earlier Mössbauer results. The ratio Tc/T(χmax) =0.68±0.01 is suggestive of quasi-two-dimensionality. In the region of the maximum an acceptable fit according to a 2D- XY model with plausible parameter values can be achieved, but only with a ferromagnetic interlayer exchange interaction about 28% as strong as the leading antiferromagnetic intralayer interaction. Isotherms of M vs H show somewhat unusual curvature, the explanation of which is unclear.

  16. Nuclear receptor subfamily 4, group A, member 1 inhibits extrinsic apoptosis and reduces caspase-8 activity in H2O2-induced human HUC-F2 fibroblasts

    PubMed Central

    Shimizu, Yuri; Miyakura, Reiko; Otsuka, Yuzuru

    2015-01-01

    Objective: Apoptosis is characterized by distinct morphological and biochemical changes that occur upon activation of a family of serine proteases known as caspases. Reactive oxygen species (ROS) induce apoptosis in many cell systems. Nuclear receptor subfamily 4, group A, member 1 (NR4A1) has been shown to induce apoptosis in a number of cell lineages, but can also paradoxically act as a death inhibitory factor. In the current study, we focused on the potential role of NR4A1 in hydrogen peroxide (H2O2)-induced apoptosis of normal human umbilical cord fibroblast (HUC-F2) cells. Methods: Growth of HUC-F2 cells treated with H2O2 was measured by MTT assay. Analysis of gene expression was performed with a STEP ONE PLUS Real Time PCR system. Inactivation of NR4A1 was treated with siRNA. Apoptosis was measured by Beckman Coulter flow cytometer after inhibition of NR4A1 with siRNA and H2O2 treatment. Caspase -3, -8 and -9 was measured by caspase assay kit. Results: H2O2 treatment led to enhanced NR4A1 expression. Moreover inhibition of NR4A1 with specific siRNA in HUC-F2 cells triggered an increase in apoptosis and caspase-8 and -3 activities following the addition of H2O2. Discussion: Our results collectively suggest that NR4A1 is a regulator that inhibits extrinsic apoptosis in HUC-F2 cells during oxidative stress through reduction of caspase-8 and -3 activities. PMID:25330024

  17. Quantitation of [5-CH3]-(2R, 4'R, 8'R)-α-Tocopherol in Humans123

    PubMed Central

    Chuang, Jennifer C.; Matel, Hosea D.; Nambiar, Krishnan P.; Kim, Seung-Hyun; Fadel, James G.; Holstege, Dirk M.; Clifford, Andrew J.

    2011-01-01

    Half-lives of α-tocopherol in plasma have been reported as 2–3 d, whereas the Elgin Study required >2 y to deplete α-tocopherol, so gaps exist in our quantitative understanding of human α-tocopherol metabolism. Therefore, 6 men and 6 women aged 27 ± 6 y (mean ± SD) ingested 1.81 nmol, 3.70 kBq of [5-14CH3]-(2R, 4'R, 8'R)-α-tocopherol. The levels of 14C in blood plasma and washed RBC were monitored frequently from 0 to 460 d while the levels of 14C in urine and feces were monitored from 0 to 21 d. Total fecal elimination (fecal + metabolic fecal) was 23.24 ± 5.81% of the 14C dose, so feces over urine was the major route of elimination of the ingested [5-14CH3]-(2R, 4′R, 8′R)-α-tocopherol, consistent with prior estimates. The half-life of α-tocopherol varied in plasma and RBC according to the duration of study. The minute dose coupled with frequent monitoring over 460 d and 21 d for blood, urine, and feces ensured the [5-14CH3]-(2R, 4'R, 8'R)-α-tocopherol (the tracer) had the chance to fully mix with the endogenous [5-14CH3]-(2R, 4'R, 8'R)-α-tocopherol (the tracee). The 14C levels in neither plasma nor RBC had returned to baseline by d 460, indicating that the t1/2 of [5-CH3]-(2R, 4′R, 8′R)-α-tocopherol in human blood was longer than prior estimates. PMID:21715470

  18. Crystal structure of the co-crystalline adduct 1,3,6,8-tetra­aza­tri­cyclo­[4.4.1.13,8]dodecane (TATD)–4-bromo­phenol (1/2)

    PubMed Central

    Rivera, Augusto; Uribe, Juan Manuel; Rojas, Jicli José; Ríos-Motta, Jaime; Bolte, Michael

    2015-01-01

    The structure of the 1:2 co-crystalline adduct C8H16N4·2C6H5BrO, (I), from the solid-state reaction of 1,3,6,8-tetra­aza­tri­cyclo­[4.4.1.13,8]dodecane (TATD) and 4-bromo­phenol, has been determined. The asymmetric unit of the title co-crystalline adduct comprises a half mol­ecule of aminal cage polyamine plus a 4-bromo­phenol mol­ecule. A twofold rotation axis generates the other half of the adduct. The primary inter-species association in the title compound is through two inter­molecular O—H⋯N hydrogen bonds. In the crystal, the adducts are linked by weak non-conventional C—H⋯O and C—H⋯Br hydrogen bonds, giving a two-dimensional supra­molecular structure parallel to the bc plane. PMID:25995856

  19. 8 CFR 1287.4 - Subpoena.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... records and evidence for use in criminal or civil investigations, see 8 CFR 287.4(a)(1). (2) Proceedings... evidence, or both, for use in any proceeding under this title, other than under 8 CFR part 335, or any application made ancillary to the proceeding, see 8 CFR 287.4(a)(2)(i). (ii) Subsequent to commencement of...

  20. Fine-tuning of CD8(+) T-cell effector functions by targeting the 2B4-CD48 interaction.

    PubMed

    Lissina, Anna; Ambrozak, David R; Boswell, Kristin L; Yang, Wenjing; Boritz, Eli; Wakabayashi, Yoshiyuki; Iglesias, Maria C; Hashimoto, Masao; Takiguchi, Masafumi; Haddad, Elias; Douek, Daniel C; Zhu, Jun; Koup, Richard A; Yamamoto, Takuya; Appay, Victor

    2016-07-01

    Polyfunctionality and cytotoxic activity dictate CD8(+) T-cell efficacy in the eradication of infected and malignant cells. The induction of these effector functions depends on the specific interaction between the T-cell receptor (TCR) and its cognate peptide-MHC class I complex, in addition to signals provided by co-stimulatory or co-inhibitory receptors, which can further regulate these functions. Among these receptors, the role of 2B4 is contested, as it has been described as either co-stimulatory or co-inhibitory in modulating T-cell functions. We therefore combined functional, transcriptional and epigenetic approaches to further characterize the impact of disrupting the interaction of 2B4 with its ligand CD48, on the activity of human effector CD8(+) T-cell clones. In this setting, we show that the 2B4-CD48 axis is involved in the fine-tuning of CD8(+) T-cell effector function upon antigenic stimulation. Blocking this interaction resulted in reduced CD8(+) T-cell clone-mediated cytolytic activity, together with a subtle drop in the expression of genes involved in effector function regulation. Our results also imply a variable contribution of the 2B4-CD48 interaction to the modulation of CD8(+) T-cell functional properties, potentially linked to intrinsic levels of T-bet expression and TCR avidity. The present study thus provides further insights into the role of the 2B4-CD48 interaction in the fine regulation of CD8(+) T-cell effector function upon antigenic stimulation. PMID:26860368

  1. New antimonato polyoxovanadates based on the [V 14IVSb 8IIIO 42(H 2O)] 4- cluster type

    NASA Astrophysics Data System (ADS)

    Antonova, Elena; Wutkowski, Adam; Näther, Christian; Bensch, Wolfgang

    2011-12-01

    Two new antimonato polyoxovanadates with compositions (enH 2) 2[V 14Sb 8O 42(H 2O)]•3H 2O ( 1) (en = ethylenediamine) and (ppzH 2) 2[V 14Sb 8O 42(H 2O)] ( 2) (ppz = piperazine) were synthesized under solvothermal conditions. Compound 1 crystallizes in the monoclinic space group P2 1/n with a = 13.6969(8) Å, b = 11.9183(10) Å, c = 19.0413(12) Å, β = 108.346(7), V = 2950.4(4) Å 3 and compound 2 crystallizes in the monoclinic space group P2 1/c with lattice parameters a = 13.7114(10) Å, b = 11.9476(5) Å, c = 19.9391(14) Å, β = 109.043(8), V = 3087.6(3) Å 3. The central structural motif of both structures can be derived from the {V 18O 42} archetype cluster replacing four VO 5 square pyramids by four Sb 2O 5 moieties yielding two perpendicular oriented eight-membered rings composed of edge-sharing VO 5 polyhedra. According to bond valence sum calculations the electronic situation in the clusters may be formulated as [V IV14Sb III8O 42(H 2O)] 4-. In compound 1 the cluster anions are arranged along the b-axis in a …ABAB… fashion, whereas the anions in 2 are stacked along the c-axis in a …AAA… mode. In both compounds neighbored clusters exhibit relatively short Sb-O separations indicating weak inter-cluster interactions, leading to a layer-like arrangement of the [V IV14Sb III8O 42(H 2O)] 4- anions. In the structure of 1 the charge balancing organic ammonium ions are fully disordered whereas the organic cations in 2 are ordered. Further characterization of compound 1 and 2 revealed that the initially used N,N,N',N'-tetramethylethylenediamine was decomposed to ethylenediamine in 1 and the applied amine 1 -methylpiperazine was fragmented to piperazine in 2. Syntheses with the latter amine led to crystallization of compound 1. But compound 2 could not be prepared applying piperazine in the reaction slurry.

  2. Antioxidant enzyme activities and lipid peroxidation in earthworm Eisenia fetida exposed to 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-γ-2-benzopyran.

    PubMed

    Liu, Shuo; Zhou, Qixing; Chen, Chun

    2012-08-01

    Polycyclic musks have been indicated to cause lethal and sublethal effects on exposed biota. However, knowledge about the effect of polycyclic musks on the antioxidant defense system in earthworms is vague. In this work, the activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and malondialdehyde (MDA) exposed to 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-γ-2-benzopyran (HHCB) were systematically investigated. The investigation shows that their activities are closely related to the exposed dose and time of HHCB. For SOD and CAT, the activities increased monotonically with increased exposed dose of HHCB, which indicates a dose-dependent change pattern. POD exhibited its peak activity in 0.0157 μg cm(-2) HHCB treatment and decreased at higher concentrations. These two changing patterns were complementary, which reveals the cooperation of enzymes in response to oxidative stress. MDA content in earthworms was basically unaffected with a 1-day exposure and significantly increased after 2-day and 3-day exposures, correlating with changes in the activities of SOD and CAT when the concentration of HHCB was high. It was also found that the sensitivity of Eisenia fetida to HHCB increased over time. These results may support the theoretical hypothesis that oxidative stress is an important component for the response of earthworms to the toxicity of HHCB in environment. Among the studied enzymes, SOD and CAT appeared to be the most responsive biomarkers of oxidative stress caused by HHCB. © 2010 Wiley Periodicals, Inc. Environ Toxicol, 2012. PMID:22764077

  3. Umbra Ver. 4.8

    2010-02-24

    Umbra is a software package that has been in development at Sandia National Laboratories since 1995, under the name Umbra since 1997. Umbra is a software framework written in C++ and Tcl/Tk that has been applied to many operations, primarily dealing with robotics and simulation. Umbra executables are C++ libraries orchestrated with Tcl/Tk scripts. Two major feature upgrades occurred from 4.7 to 4.8 1. System Umbra Module with its own Update Graph within the C++more » framework. 2. New terrain graph for fast line-of-sight calculations All else were minor updates such as later versions of Visual Studio, OpenSceneGraph and Boost.« less

  4. Synthesis and photophysical properties of the 2-(3-(2-Alkyl-6,8-diaryl-4-oxo-1,2,3,4-tetrahydroquinazolin-2-yl)propyl)-6,8-diarylquinazolin-4(3H)-ones.

    PubMed

    Mmonwa, Mmakwena M; Mphahlele, Malose J; El-Hendawy, Morad M; El-Nahas, Ahmed M; Koga, Nobuaki

    2014-01-01

    Iodine-catalyzed condensation of 2-amino-3,5-dibromobenzamide with cyclohexane-1,3-dione derivatives in refluxing toluene afforded the corresponding bisquinazolinones. Suzuki-Miyaura cross-coupling of the latter with arylboronic acids afforded tetraarylbisquinazolinones. The electronic absorption and emission properties of these tetraarylbisquinazolinones were measured in dimethylsulfoxide (DMSO) and acetic acid by means of UV-Vis and fluorescence spectroscopic techniques in conjunction with quantum chemical methods to understand the influence of substituents on intramolecular charge transfer (ICT). PMID:25006782

  5. Upper critical field of high temperature Y(1.2)Ba(0.8)CuO(4-delta) superconductor

    NASA Technical Reports Server (NTRS)

    Hor, P. H.; Meng, R. L.; Huang, J. Z.; Chu, C. W.; Huang, C. Y.

    1987-01-01

    A 20-T high-field magnet is used to measure electrical resistance as a function of temperature in the Y(1.2)Ba(0.8)CuO(4-delta) superconductor. The temperature dependence of the critical field, Hc2(T), is obtained from the superconduction transition. A Hc2(O) value of 166T is determined which is the highest critical field yet reported. Results show Y(1.2)Ba(0.8)CuO(4-delta) to be a 90K Type-II superconductor, with a lower critical field Hc1(O) of about 0.2T and a penetration depth of about 290 A.

  6. Absolutely calibrated radio polarimetry of the inner Galaxy at 2.3 and 4.8 GHz

    NASA Astrophysics Data System (ADS)

    Sun, X. H.; Gaensler, B. M.; Carretti, E.; Purcell, C. R.; Staveley-Smith, L.; Bernardi, G.; Haverkorn, M.

    2014-01-01

    We present high-sensitivity and absolutely calibrated images of diffuse radio polarization at a resolution of about 10 arcmin covering the range 10° < l < 34° and |b| < 5° at 2.3 GHz from the S-band Polarization All Sky Survey and at 4.8 GHz from the Sino-German λ6 cm polarization survey of the Galactic plane. Strong depolarization near the Galactic plane is seen at 2.3 GHz, which correlates with strong Hα emission. We ascribe the depolarization to spatial Faraday rotation measure fluctuations of about 65 rad m-2 on scales smaller than 6-9 pc. We argue that most (about 90 per cent) of the polarized emission seen at 4.8 GHz originates from a distance of 3-4 kpc in the Scutum arm and that the random magnetic field dominates the regular field there. A branch extending from the North Polar Spur towards lower latitudes can be identified from the polarization image at 4.8 GHz but only partly from the polarization image at 2.3 GHz, implying that the branch is at a distance larger than 2-3 kpc. We show that comparison of structure functions of complex polarized intensity with those of polarized intensity can indicate whether the observed polarized structures are intrinsic or caused by Faraday screens. The probability distribution function of gradients from the polarization images at 2.3 GHz indicates that the turbulence in the warm ionized medium is transonic.

  7. Application of Si and SiO2 Etching Mechanisms in CF4/C4F8/Ar Inductively Coupled Plasmas for Nanoscale Patterns.

    PubMed

    Lee, Junmyung; Efremov, Alexander; Yeom, Geun Young; Lim, Nomin; Kwon, Kwang-Ho

    2015-10-01

    An investigation of the etching characteristics and mechanism for both Si and SiO2 in CF4/C4F8/Ar inductively coupled plasmas under a constant gas pressure (4 mTorr), total gas flow rate (40 sccm), input power (800 W), and bias power (150 W) was performed. It was found that the variations in the CF4/C4F8 mixing ratio in the range of 0-50% at a constant Ar fraction of 50% resulted in slightly non-monotonic Si and SiO2 etching rates in CF4-rich plasmas and greatly decreasing etching rates in C4F8-rich plasmas. The zero-dimensional plasma model, Langmuir probe diagnostics, and optical emission spectroscopy provided information regarding the formation-decay kinetics for the plasma active species, along with their densities and fluxes. The model-based analysis of the etching kinetics indicated that the non-monotonic etching rates were caused not by the similar behavior of the fluorine atom density but rather by the opposite changes of the fluorine atom flux and ion energy flux. It was also determined that the great decrease in both the Si and SiO2 etching rates during the transition from the CF4/Ar to C4F8/Ar gas system was due to the deposition of the fluorocarbon polymer film. PMID:26726514

  8. 2,8-Disubstituted-1,6-Naphthyridines and 4,6-Disubstituted-Isoquinolines with Potent, Selective Affinity for CDK8/19.

    PubMed

    Mallinger, Aurélie; Schiemann, Kai; Rink, Christian; Sejberg, Jimmy; Honey, Mark A; Czodrowski, Paul; Stubbs, Mark; Poeschke, Oliver; Busch, Michael; Schneider, Richard; Schwarz, Daniel; Musil, Djordje; Burke, Rosemary; Urbahns, Klaus; Workman, Paul; Wienke, Dirk; Clarke, Paul A; Raynaud, Florence I; Eccles, Suzanne A; Esdar, Christina; Rohdich, Felix; Blagg, Julian

    2016-06-01

    We demonstrate a designed scaffold-hop approach to the discovery of 2,8-disubstituted-1,6-naphthyridine- and 4,6-disubstituted-isoquinoline-based dual CDK8/19 ligands. Optimized compounds in both series exhibited rapid aldehyde oxidase-mediated metabolism, which could be abrogated by introduction of an amino substituent at C5 of the 1,6-naphthyridine scaffold or at C1 of the isoquinoline scaffold. Compounds 51 and 59 were progressed to in vivo pharmacokinetic studies, and 51 also demonstrated sustained inhibition of STAT1(SER727) phosphorylation, a biomarker of CDK8 inhibition, in an SW620 colorectal carcinoma human tumor xenograft model following oral dosing. PMID:27326329

  9. Structural, Functional, and Immunological Characterization of Profilin Panallergens Amb a 8, Art v 4, and Bet v 2.

    PubMed

    Offermann, Lesa R; Schlachter, Caleb R; Perdue, Makenzie L; Majorek, Karolina A; He, John Z; Booth, William T; Garrett, Jessica; Kowal, Krzysztof; Chruszcz, Maksymilian

    2016-07-22

    Ragweed allergens affect several million people in the United States and Canada. To date, only two ragweed allergens, Amb t 5 and Amb a 11, have their structures determined and deposited to the Protein Data Bank. Here, we present structures of methylated ragweed allergen Amb a 8, Amb a 8 in the presence of poly(l-proline), and Art v 4 (mugwort allergen). Amb a 8 and Art v 4 are panallergens belonging to the profilin family of proteins. They share significant sequence and structural similarities, which results in cross-recognition by IgE antibodies. Molecular and immunological properties of Amb a 8 and Art v 4 are compared with those of Bet v 2 (birch pollen allergen) as well as with other allergenic profilins. We purified recombinant allergens that are recognized by patient IgE and are highly cross-reactive. It was determined that the analyzed allergens are relatively unstable. Structures of Amb a 8 in complex with poly(l-proline)10 or poly(l-proline)14 are the first structures of the plant profilin in complex with proline-rich peptides. Amb a 8 binds the poly(l-proline) in a mode similar to that observed in human, mouse, and P. falciparum profilin·peptide complexes. However, only some of the residues that form the peptide binding site are conserved. PMID:27231348

  10. A vibrational spectroscopic study of planchéite Cu8Si8O22(OH)4·H2O

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; Xi, Yunfei

    2012-06-01

    Planchéite Cu8Si8O22(OH)4·H2O is a hydrated copper hydroxy silicate. Raman spectroscopy complimented with infrared spectroscopy has been used to determine the molecular structure of planchéite. Raman bands at around 1048, 1081 and 1127 are described as the ν1-SiO3 symmetric stretching vibrations; Raman bands at 828, 906 are attributed to the ν3-SiO3 antisymmetric stretching vibrations. The Raman band at 699 cm-1 is assigned to the ν4 bending modes of the sbnd SiO3 units. The intense Raman band at 3479 cm-1 is ascribed to the stretching vibration of the OH units. The Raman band at 3250 cm-1 is evidence for water in the structure.

  11. R22(8) motifs in Aminopyrimidine sulfonate/carboxylate interactions: Crystal structures of pyrimethaminium benzenesulfonate monohydrate (2:2:1) and 2-amino-4,6-dimethylpyrimidinium sulfosalicylate dihydrate (4:2:2)

    PubMed Central

    Balasubramani, Kasthuri; Muthiah, Packianathan Thomas; Lynch, Daniel E

    2007-01-01

    Background Pyrimethamine [2,4-diamino-5-(p-chlorophenyl)-6-ethylpyrimidine] is an antifolate drug used in anti-malarial chemotherapy. Pyrimidine and aminopyrimidine derivatives are biologically important compounds owing to their natural occurrence as components of nucleic acids. Results In the crystal structures of two organic salts, namely pyrimethaminium benzenesulfonate monohydrate 1 and 2-amino-4, 6-dimethylpyrimidinium 3-carboxy-4-hydroxy benzenesulfonate dihydrate 2, pyrimethamine (PMN) and 2-amino-4,6-dimethylpyrimidine (AMPY) are protonated at one of the nitrogens in the pyrimidine rings. In both the PMN and AMPY sulfonate complexes, the protonated pyrimidine rings are hydrogen bonded to the sulfonate groups, forming a hydrogen-bonded bimolecular ring motif with graph-set notation R22(8). The sulfonate group mimics the carboxylate anion's mode of association, which is more commonly seen when binding with 2-aminopyrimidines. In compound 1, the PMN moieties are centrosymmetrically paired through a complementary DADA array of hydrogen bonds. In compound 2, two types of bimolecular cyclic hydrogen bonded R22(8) motifs (one involving the carboxylate group and the other involving sulfonate group) coexist. Furthermore, this compound is stabilized by intra and intermolecular O-H...O hydrogen bonds. Conclusion The crystal structures of pyrimethaminium benzenesulfonate monohydrate and 2-amino-4,6-dimethylpyrimidinium sulfosalicylate dihydrate have been investigated in detail. In compound 1, the R22(8) motif involving the sulfonate group is present. The role the sulfonic acid group plays in mimicking the carboxylate anions is thus evident. In compound 2, two types of bimolecular cyclic hydrogen bonded R22(8) motifs (one involving the carboxylate group and the other involving sulfonate group) coexist. In both the compounds base pairing also occurs. Thus homo and hetero synthons are present. PMID:17999751

  12. Na8[Cr4B12P8O44(OH)4][P2O7].nH2O: a 3D borophosphate framework with spherical cages.

    PubMed

    Yang, Tao; Sun, Junliang; Li, Guobao; Eriksson, Lars; Zou, Xiaodong; Liao, Fuhui; Lin, Jianhua

    2008-01-01

    A chromium borophosphate-phosphate (Na(8)[Cr(4)B(12)P(8)O(44)(OH)(4)][P(2)O(7)]nH(2)O, 1), which has an unusual 3D framework structure, was synthesized under hydrothermal conditions. The framework consists of spherical cages composed of CrO(6), PO(4), BO(4), and BO(3) polyhedra. The cages are located at the vertices and the body center of the cubic cell and are interconnected through 12-membered-ring windows along the {111} direction. The actual framework structure is very complex, but the description can be simplified by using the 5-connected fundamental building cluster [CrP(5)B(3)O(24)](11-). In addition, 1 represents the first borate-rich borophosphate that contains a 3D borophosphate partial framework (3(over)infinity[B(3)P(2)O(11)(OH)]) in which the fundamental building unit is an oB dreier single ring (Delta4 square:square2 square> square). The cavities of the framework are filled with disengaged water molecules and Na(+) counterions. The former can be reversibly desorbed and reabsorbed and the latter can be exchanged by Li(+) ions, which results in significant shrinkages of the cell volume. PMID:18624289

  13. Adsorption of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) on a soil organic matter. A DFT M05 computational study.

    PubMed

    Sviatenko, Liudmyla K; Gorb, Leonid; Shukla, Manoj K; Seiter, Jennifer M; Leszczynska, Danuta; Leszczynski, Jerzy

    2016-04-01

    Adsorption of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) by soil organic matter considering the Leonardite Humic Acid (LHA) model at the M05/tzvp level of Density Functional Theory (DFT) applying cluster approximation has been investigated. Different orientations of CL-20 toward LHA surface were examined. It was found that deprotonation of LHA is required to obtain stable complexes with CL-20. Hydrogen bonds between CL-20 and deprotonated LHA were analyzed applying the atoms in molecules (AIM) theory. An attachment or removal of an electron with respect to the complex does not have significant effect on mutual orientation of the adsorbent in complexes. It was shown that adsorbed CL-20 does not undergo redox transformation and, therefore, adsorption on soil organic matter may be responsible for decrease of the degradation rate of CL-20 in soil. PMID:26814703

  14. Shh, Bmp-2, Bmp-4 and Fgf-8 are associated with initiation and patterning of mouse tongue papillae.

    PubMed

    Jung, H S; Oropeza, V; Thesleff, I

    1999-03-01

    Spacing patterns are of fundamental importance in various repeated structures which develop at regular intervals such as feathers, teeth and insect ommatidia. The mouse tongue develops a regular papilla pattern and provides a good model to study pattern formation. We examined the expression patterns of the signalling molecules, sonic hedgehog (Shh), bone morphogenetic proteins -2 and -4 (Bmp-2 and Bmp-4), and fibroblast growth factor-8 (Fgf-8) in mouse embryos between E 10.5 and 15. We show that all four genes are expressed uniformly in the tongue epithelium between E 10.5 and 11. At E 13, before morphologically detectable gustatory papillae initiation, Shh, Bmp-2 and Bmp-4 expression segregates into discrete spots, whereas, Fgf-8 is downregulated. At E 14, small eminences in the anterior part of the tongue are the first morphological indications of fungiform papillae, and they express Shh and Bmp-2, whereas, Bmp-4 is almost absent in the tongue. We conclude that these conserved signalling molecules are associated with the initiation and early morphogenesis of the tongue papillae. PMID:10330496

  15. Molecular structure and protonation trends in 6-methoxy- and 8-methoxy-2,4,5-tris(dimethylamino)quinolines

    NASA Astrophysics Data System (ADS)

    Dyablo, O. V.; Pozharskii, A. F.; Shmoilova, E. A.; Ozeryanskii, V. A.; Fedik, N. S.; Suponitsky, K. Yu.

    2016-03-01

    Molecular structure and protonation trends of 6-methoxy- 7 and 8-methoxy- 8 derivatives of 2,4,5-tris(dimethylamino)quinoline were studied using X-ray measurements, NMR spectra and theoretical calculations. It has been found that while 8 in the solid state forms protic salts of a quinolinium type, its isomer 7 behaves as a typical proton sponge giving the anilinium cation with a proton chelated by peri-NMe2 groups. In solution, both compounds are simultaneously monoprotonated at two possible centers but again a tendency of 7 to form anilinium cation is much higher if compared to 8. It has been also shown that basicity of 7 is the largest among all known derivatives of 4,5-bis(dimethylamino)quinoline and even slightly exceeds that of 1,8-bis(dimethylamino)naphthalene (parent proton sponge). This was attributed to the "buttressing effect" exhibited by the 6-MeO group. Stable double salts of 7 with picrate and perchlorate anions unprecedented for azines with conjugated aza and NMe2 groups were obtained and thoroughly studied.

  16. Unusual Yb magnetic properties in YbMn6Ge1.8-xSn4.2Gax and YbMn6Ge1.8Sn4.2-yGay

    NASA Astrophysics Data System (ADS)

    Eichenberger, L.; Malaman, B.; Mazet, T.

    2016-05-01

    We investigate the magnetic properties of the new HfFe6Ge6-type (P6/mmm) YbMn6Ge1.8-xSn4.2Gax (x=0.05, 0.4 and 0.9) and YbMn6Ge1.8Sn4.2-yGay (y=0.05, 0.5 and 1.0) alloys from DC magnetization and powder neutron diffraction experiments. The electronic structure modifications induced by the Ga substitution are found to promote the ferromagnetic order of the Mn sublattice, to enhance the Yb ordering temperature (up to TYb∼170 K) and to strongly increase the low-temperature coercive field (up to μ0Hc∼1 T). By contrast, the changes in the Yb magnetic moment magnitude upon Ga substitution are analyzed to be mainly driven by chemical pressure effects. The reduced Yb magnetic moment (1.0 μB8 μB) compared with the free ion value (4 μB) is interpreted as resulting from Kondo screening. There are strong indirect indications that the high temperature Yb magnetic ordering likely involves intermediate valent Yb.

  17. The thermodynamic properties of 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene

    SciTech Connect

    Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.; Smith, N.K.; Steele, W.V.

    1992-12-01

    Measurements leading to the calculation of the ideal-gas thermodynamic properties are reported for 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene. Experimental methods included combustion calorimetry, adiabatic heat-capacity calorimetry, vibrating-tube densitometry, comparative ebulliometry, inclined-piston gauge manometry, and differential-scanning calorimetry (d.s.c.). Critical properties were estimated for both materials based on the measurement results. Entropies, enthalpies, and Gibbs energies of formation were derived for the ideal gases for selected temperatures between 380 K and 700 K. The property-measurement results reported here for 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene are the first for these important intermediates in the pyrene/H{sub 2} hydrogenation reaction network.

  18. Novel bismuth oxophosphate halides [Bi8O8][BiO2](PO4)2X (X=Cl, Br) based on oxocentered 2D blocks and their relationships to the Aurivillius phases

    NASA Astrophysics Data System (ADS)

    Kozin, Michael S.; Aliev, Almaz; Colmont, Marie; Mentré, Olivier; Siidra, Oleg I.; Krivovichev, Sergey V.

    2013-03-01

    Two new bismuth phosphate halides [Bi8O8][BiO2](PO4)2Cl and [Bi8O8][BiO2](PO4)2Br, high-temperature phases have been obtained by the solid-state reaction method. Oa-Bi bonds (Oa—additional oxygen atoms not bonded to P) are the shortest and therefore the strongest in the studied structures, which makes it reasonable to consider the Bi-O substructure consisting of OBi4 tetrahedra and OBi3 triangles as an independent structural unit interacting with X atoms and PO4 tetrahedra through relatively weak Bi-X and Bi-O bonds. The topology of this oxocentered Bi-O structural unit is two-dimensional and obviously related to the [O2Bi2]2+ layer typical for the Aurivillius type compounds. The formula of the oxocentered block is ([O8Bi8][O2Bi])7+ with the first part in square brackets designating the moiety formed by the OBi4 tetrahedra, whereas the second part shows 3-coordinated O atoms and the Bi atoms not participating in the OBi4 tetrahedra. The interlayer in between the oxocentered 2D blocks is occupied by the phosphate groups and halogen atoms which are organized in alternating stripes. In the case of studied bismuth oxyphosphate halides as well as in other previously reported compounds, 'additional' oxygen atoms can be considered as segregation centers for Bi3+ cations. This viewpoint may appear to be useful for design of new schemes and synthetic routes to the bismuth oxysalt compounds with different structural architectures and possible useful applications. The comparison with the similar stairs-like layers in bismuth oxysalt structures is also given.

  19. The crystal structure and morphology of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20) p-xylene solvate: a joint experimental and simulation study.

    PubMed

    Shen, Fanfan; Lv, Penghao; Sun, Chenghui; Zhang, Rubo; Pang, Siping

    2014-01-01

    The crystal structure of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaiso-wurtzitane (CL-20) p-xylene solvate, and the solvent effects on the crystal faces of CL-20 were studied through a combined experimental and theoretical method. The properties were analyzed by thermogravimetry-differential scanning calorimetry (TG-DSC), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD).The growth morphology of CL-20p-xylene solvate crystal was predicted with a modified attachment energy model. The crystal structure of CL-20p-xylene solvate belonged to the Pbca space group with the unit cell parameters, a=8.0704(12) Å, b=13.4095(20) Å, c=33.0817(49) Å, and Z=4, which indicated that the p-xylene solvent molecules could enter the crystal lattice of CL-20 and thus the CL-20 p-xylene solvate is formed. According to the solvent-effected attachment energy calculations, (002) and (11-1) faces should not be visible at all, while the percentage area of the (011) face could be increased from 7.81% in vacuum to 12.51% in p-xylene solution. The predicted results from the modified attachment energy model agreed very well with the observed morphology of crystals grown from p-xylene solution. PMID:25401400

  20. Preparation and electromagnetic properties of Polyaniline(polypyrrole)-BaFe12O19/Ni0.8Zn0.2Fe2O4 ferrite nanocomposites

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Huang, Ying; Wang, Qiufen; He, Qian; Chen, Lin

    2012-10-01

    The nanocomposite of hard (BaFe12O19)/soft ferrite (Ni0.8Zn0.2 Fe2O4) was prepared by the sol-gel process, and then the polyaniline(PANI)/polypyrrole(PPY)-BaFe12O19/Ni0.8Zn0.2Fe2O4 was produced by in situ polymerization method. The structures, morphology and electromagnetic properties of the samples were characterized by various instruments. XRD, TEM, and FTIR analysis indicated that BaFe12O19/Ni0.8Zn0.2Fe2O4 ferrite were homogenously enwrapped by PANI(PPY) coating. The VSM and SDY-4 measurement show that the magnetic properties of the composites decreased with the increase in PANI(PPY) amount, However, the electrical conductivity is on the contrary. The electromagnetic properties of the composites were much better than BaFe12O19/Ni0.8Zn0.2Fe2O4 in the frequency range of 2-15 GHz, which mainly depends on the dielectric loss of PANI(PPY). A minimum reflection loss of the PANI(PPY)-BaFe12O19/Ni0.8Zn0.2Fe2O4 ferrite nanocomposite is -19.7 dB(-21.5 dB) at the frequency of 7.3 GHz (10.7 GHz).

  1. Avian influenza virus hemagglutinins H2, H4, H8, and H14 support a highly pathogenic phenotype

    PubMed Central

    Veits, Jutta; Weber, Siegfried; Stech, Olga; Breithaupt, Angele; Gräber, Marcus; Gohrbandt, Sandra; Bogs, Jessica; Hundt, Jana; Teifke, Jens P.; Mettenleiter, Thomas C.; Stech, Jürgen

    2012-01-01

    High-pathogenic avian influenza viruses (HPAIVs) evolve from low-pathogenic precursors specifying the HA serotypes H5 or H7 by acquisition of a polybasic HA cleavage site. As the reason for this serotype restriction has remained unclear, we aimed to distinguish between compatibility of a polybasic cleavage site with H5/H7 HA only and unique predisposition of these two serotypes for insertion mutations. To this end, we introduced a polybasic cleavage site into the HA of several low-pathogenic avian strains with serotypes H1, H2, H3, H4, H6, H8, H10, H11, H14, or H15, and rescued HA reassortants after cotransfection with the genes from either a low-pathogenic H9N2 or high-pathogenic H5N1 strain. Oculonasal inoculation with those reassortants resulted in varying pathogenicity in chicken. Recombinants containing the engineered H2, H4, H8, or H14 in the HPAIV background were lethal and exhibited i.v. pathogenicity indices of 2.79, 2.37, 2.85, and 2.61, respectively, equivalent to naturally occurring H5 or H7 HPAIV. Moreover, the H2, H4, and H8 reassortants were transmitted to some contact chickens. The H2 reassortant gained two mutations in the M2 proton channel gate region, which is affected in some HPAIVs of various origins. Taken together, in the presence of a polybasic HA cleavage site, non-H5/H7 HA can support a highly pathogenic phenotype in the appropriate viral background, indicating requirement for further adaptation. Therefore, the restriction of natural HPAIV to serotypes H5 and H7 is likely a result of their unique predisposition for acquisition of a polybasic HA cleavage site. PMID:22308331

  2. Isomorphous Substitution of Rare-Earth Elements in Lacunary Apatite Pb8Na2(PO4)6.

    PubMed

    Get'man, Evgeni I; Loboda, Stanislav N; Ignatov, Alexey V; Prisedsky, Vadim V; Abdul Jabar, Mohammed A B; Ardanova, Lyudmyla I

    2016-03-01

    The substitution of rare-earth elements (REEs) for Pb in the lacunary apatite Pb8Na2(PO4)6 with void structural channels was studied by means of powder X-ray diffraction (including the Rietveld refinement), scanning electron microscopy, energy-dispersive X-ray microanalysis, and IR spectroscopy and also measurements of the electrical conductivity. The substitution limits (xmax in Pb8-xLnxNa2(PO4)6Ox/2) at 800 °C were found to decrease with the atomic number of the REE from 1.40 for La to 0.12 for Yb with a rapid drop from light to heavy lanthanides (between Gd and Tb). The REE atoms substitute for Pb predominantly at Pb2 sites of the apatite structure according to the scheme 2Pb(2+) + □ → 2Ln(3+) + O(2-), where □ is a vacancy in the structural channel. The substitution in lacunary apatite produces quite different changes in the structural parameters compared with broadly studied alkaline-earth hydroxyapatites. In spite of the much lower ionic radii of REE than that of Pb(2+), the mean distances ⟨Pb1-O⟩ somewhat increase, whereas the distances ⟨Pb2-Pb2⟩ and ⟨Pb2-O4⟩ do not change considerably with the degree of substitution. This implies control of the substitution by not only spatial and charge accommodation of REE ions but also the availability of a stereochemically active 6s(2) electron pair on Pb(2+). The high-temperature electrical conductivity shows dependence on the degree of substitution with a minimum at x = 0.2 indicative of a possible change of the type of conductivity. PMID:26871754

  3. MELCOR 1.8.2 assessment: The DF-4 BWR Damaged Fuel experiment

    SciTech Connect

    Tautges, T.J.

    1993-10-01

    MELCOR is a fully integrated, engineering-level computer code being developed at Sandia National Laboratories for the USNRC, that models the entire spectrum of severe accident phenomena in a unified framework for both BWRs and PWRs. As a part of an ongoing assessment, program, MELCOR has been used to model the ACRR in-pile DF-4 Damaged Fuel experiment. DF-4 provided data for early phase melt progression in BWR fuel assemblies, particularly for phenomena associated with eutectic interactions in the BWR control blade and zircaloy oxidation in the canister and cladding. MELCOR provided good agreement with experimental data in the key areas of eutectic material behavior and canister and cladding oxidation. Several shortcomings associated with the MELCOR modeling of BWR geometries were found and corrected. Twenty-five sensitivity studies were performed on COR, HS and CVH parameters. These studies showed that the new MELCOR eutectics model played an important role in predicting control blade behavior. These studies revealed slight time step dependence and no machine dependencies. Comparisons made with the results from four best-estimate codes showed that MELCOR did as well as these codes in matching DF-4 experimental data.

  4. Chemical and Thermoelectric Properties of Hot Pressed and Spark Plasma Sintered Type-I Clathrate Ba8Cu4.8Si41.2

    NASA Astrophysics Data System (ADS)

    Yan, X.; Populoh, S.; Weidenkaff, A.; Rogl, P.; Paschen, S.

    2016-03-01

    Nanostructuring has been considered as an effective way to reduce the thermal conductivity and enhance the thermoelectric performance in different material systems. Here, we present the chemical and thermoelectric properties of the nanostructured bulk type-I clathrate Ba8Cu4.8Si41.2. The samples were prepared by consolidating ball-milled nanopowders either by hot pressing or by spark plasma sintering. Fine powders and high sintering temperatures are needed to reach a high bulk density and high thermoelectric performance in the sintered samples. The highest ZT of 0.3 at 870 K is achieved in the most dense sample sintered at 800°C by hot pressing. Further improvement is expected if smaller grain sizes could be stabilized.

  5. The dimeric [V{sub 2}O{sub 2}F{sub 8}]{sup 4−} anion: Structural characterization of a magnetic basic-building-unit

    SciTech Connect

    Lu, Hongcheng; Gautier, Romain; Li, Zuo-Xi; Jie, Wanqi; Liu, Zhengtang; Poeppelmeier, Kenneth R.

    2013-04-15

    New materials built from the [V{sub 2}O{sub 2}F{sub 8}]{sup 4−} anionic basic-building-unit (BBU) exhibit interesting magnetic properties owing to the proximity of the two d{sup 1} V(IV) cations and the orbital interactions of fluoride and oxide ligands. In our search to target such materials, the vanadium oxide–fluoride compound [dpaH{sub 2}]{sub 2}[V{sub 2}O{sub 2}F{sub 8}] in which a dimeric anion [V{sub 2}O{sub 2}F{sub 8}]{sup 4−} is isolated in a hydrogen bond network was hydrothermally synthesized (dpa=2,2′-dipyridylamine). This hydrogen bond network is able to stabilize the highly ionic species [V{sub 2}O{sub 2}F{sub 8}]{sup 4−} as demonstrated with bond valence calculations. The coordination of the O{sup 2−}/F{sup −} ordered ligands was investigated and antiferromagnetic coupling of the isolated BBU was measured. - The new hybrid compound [dpaH{sub 2}]{sub 2}[V{sub 2}O{sub 2}F{sub 8}] built from the interesting [V{sub 2}O{sub 2}F{sub 8}]{sup 4−} magnetic basic-building-unit (BBU) was synthesized by the hydrothermal method. The coordination of the O{sup 2−}/F{sup −} ordered ligands was investigated by BVS calculations and antiferromagnetic coupling was measured. Highlights: ► A new vanadium oxyfluoride was synthesized by hydrothermal method. ► The Dimeric [V{sub 2}O{sub 2}F{sub 8}]{sup 4−} basic building unit is isolated in the hydrogen bond networks. ► The coordination of [V{sub 2}O{sub 2}F{sub 8}]{sup 4−} units to the extended structure is investigated. ► Isolated [V{sub 2}O{sub 2}F{sub 8}]{sup 4−} units exhibit antiferromagnetic coupling.

  6. A near infrared imaging polarimetry investigation of the bipolar proto-planetary nebula - OH231.8+4.2

    NASA Astrophysics Data System (ADS)

    Ahmad, Amir

    Proto-Planetary-Nebulae (PPNe) are a class of short-lived transitionary objects. They represent a period of a round a few 1000 years of stellar evolution between the Asymptotic Giant Branch (AGB) and Planetary Nebula (PN) phase. This part of the Hertzsprung-Russell (HR) diagram is not very well understood from theory, although it represents an important phase of low and intermediate mass (0.8 Msun < M < 8 Msun) stellar evolution. The unsolved problems are the formation and destruction of dust grains, the nature of their coupling to the gas, the physical processes driving the mass-loss, as well as the occurrence of bipolarity and formation of a disk-like torus. The AGB circumstellar envelope (CSE) is mostly spherical whereas the majority of PNe are bipolar. It is thought that the transition from spherical to axisymmetry takes places during the PPN phase. Near infrared (NIR) imaging polarimetry tells us about the dust density, as well as the grain size distribution. It lets us determine the morphological structure of the nebula and gives us some indication about the mass loss. Here we present NIR imaging polarimetry of OH231.8+4.2 (Rotten Egg nebula). It is a very well studied object thought to be at the end of the AGB but is unusual in the sense that, its central star is thought to be a "classical" Mira. We present NIR linear and circular polarimetry of the bipolar outflow of the nebula in the broad band at J (1.25 microns), H (1.65 microns) and K (2.2 microns). We use a Monte Carlo (MC) light scattering code to model the NIR intensities, colours and polarisation levels for this PPN, the results of which are presented. We detect high linear polarisation in OH231.8+4.2 (~ 50%) in the lobes of the nebula at J, H and K. We also detect maximum circular polarisation of (~ 1.7%) in the J band which is probably the first detection in a PPN. Based on our MC modelling we suggest that the majority of particles in OH231.8+4.2 are Rayleigh-like and are responsible for the high

  7. Adaptable coordination of U(IV) in the 2D-(4,4) uranium oxalate network: From 8 to 10 coordinations in the uranium (IV) oxalate hydrates

    SciTech Connect

    Duvieubourg-Garela, L.; Vigier, N. Grandjean, S.

    2008-08-15

    Crystals of uranium (IV) oxalate hydrates, U(C{sub 2}O{sub 4}){sub 2}.6H{sub 2}O (1) and U(C{sub 2}O{sub 4}){sub 2}.2H{sub 2}O (2), were obtained by hydrothermal methods using two different U(IV) precursors, U{sub 3}O{sub 8} oxide and nitric U(IV) solution in presence of hydrazine to avoid oxidation of U(IV) into uranyl ion. Growth of crystals of solvated monohydrated uranium (IV) oxalate, U(C{sub 2}O{sub 4}){sub 2}.H{sub 2}O.(dma) (3), dma=dimethylamine, was achieved by slow diffusion of U(IV) into a gel containing oxalate ions. The three structures are built on a bi-dimensional complex polymer of U(IV) atoms connected through bis-bidentate oxalate ions forming [U(C{sub 2}O{sub 4})]{sub 4} pseudo-squares. The flexibility of this supramolecular arrangement allows modifications of the coordination number of the U(IV) atom which, starting from 8 in 1 increases to 9 in 3 and, finally increases, to 10 in 2. The coordination polyhedron changes from a distorted cube, formed by eight oxygen atoms of four oxalate ions, in 1, to a mono-capped square anti-prism in 3 and, finally, to a di-capped square anti-prism in 2, resulting from rotation of the oxalate ions and addition of one and two water oxygen atoms in the coordination of U(IV). In 1, the space between the {sub {infinity}}{sup 2}[U(C{sub 2}O{sub 4}){sub 2}] planar layers is occupied by non-coordinated water molecules; in 2, the space between the staggered {sub {infinity}}{sup 2}[U(C{sub 2}O{sub 4}){sub 2}.2H{sub 2}O] layers is empty, finally in 3, the solvate molecules occupy the interlayer space between corrugated {sub {infinity}}{sup 2}[U(C{sub 2}O{sub 4}){sub 2}.H{sub 2}O] sheets. The thermal decomposition of U(C{sub 2}O{sub 4}){sub 2}.6H{sub 2}O under air and argon atmospheres gives U{sub 3}O{sub 8} and UO{sub 2}, respectively. - Graphical abstract: The adaptable environment of U(IV) in U(IV) oxalates: from eight cubic coordination in U(C{sub 2}O{sub 4}){sub 2}.6H{sub 2}O (a) completed by water oxygens to nine in

  8. New N-bearing species towards OH 231.8+4.2. HNCO, HNCS, HC3N, and NO

    NASA Astrophysics Data System (ADS)

    Velilla Prieto, L.; Sánchez Contreras, C.; Cernicharo, J.; Agúndez, M.; Quintana-Lacaci, G.; Alcolea, J.; Bujarrabal, V.; Herpin, F.; Menten, K. M.; Wyrowski, F.

    2015-03-01

    Circumstellar envelopes (CSEs) around asymptotic giant branch (AGB) stars are the main sites of molecular formation. OH 231.8+4.2 is a well studied oxygen-rich CSE around an intermediate-mass evolved star that, in dramatic contrast to most AGB CSEs, displays bipolar molecular outflows accelerated up to ~400 km s-1. OH 231.8+4.2 also presents an exceptional molecular richness probably due to shock-induced chemical processes. We report the first detection in this source of four nitrogen-bearing species, HNCO, HNCS, HC3N, and NO, which have been observed with the IRAM-30 m radiotelescope in a sensitive mm-wavelength survey towards this target. HNCO and HNCS are also first detections in CSEs. The observed line profiles show that the emission arises in the massive (~0.6 M⊙) central component of the envelope, expanding with low velocities of Vexp~ 15-30 km s-1, and at the base of the fast lobes. The NO profiles (with FWHM~ 40-50 km s-1) are broader than those of HNCO, HNCS, and HC3N and, most importantly, broader than the line profiles of 13CO, which is a good mass tracer. This indicates that the NO abundance is enhanced in the fast lobes relative to the slow, central parts. From LTE and non-LTE excitation analysis, we estimate beam-average rotational temperatures of Trot~ 15-30 K (and, maybe, up to ~55 K for HC3N) and fractional abundances relative to H2 of X(HNCO) ~ [0.8-1] × 10-7, X(HNCS) ~ [0.9-1] × 10-8, X(HC3N) ~ [5-7] × 10-9, and X(NO) ~ [1-2] × 10-6. NO is, therefore, amongst the most abundant N-bearing species in OH 231.8+4.2. We performed thermodynamical chemical equilibrium and chemical kinetics models to investigate the formation of these N-bearing species in OH 231.8+4.2. The model underestimates the observed abundances for HNCO, HNCS, and HC3N by several orders of magnitude, which indicates that these molecules can hardly be products of standard UV-photon and/or cosmic-ray induced chemistry in OH 231.8+4.2 and that other processes (e.g. shocks) play a

  9. Raman and infrared spectroscopic characterization of the phosphate mineral paravauxite Fe2+Al2(PO4)2(OH)2.8H2O.

    PubMed

    Frost, Ray L; Scholz, Ricardo; Lópes, Andrés; Xi, Yunfei; Gobac, Zeljka Žigovečki; Horta, Laura Frota Campos

    2013-12-01

    We have undertaken a vibrational spectroscopic study of paravauxite the Siglo XX mine, Bustillo Province, northern of Potosí department, Bolivia. This mine is important source for rare and unusual secondary phosphate minerals and is the type locality for a number of rare phosphates such as vauxite, sigloite, metavauxite and for jeanbandyite. The chemical formula of the studied sample was determined as Fe(2+)(0.9)5, Al(0.07)Σ1.02 (Al)2.09 (PO4)1:97 (OH)1.98 · 7.90(H2O). The Raman spectrum is dominated by an intense Raman band at 1020 cm(-1) assigned to the PO4(3-) ν1 symmetric stretching mode. Low intensity Raman bands found at 1058, 1115 and 1148 cm(-1) are assigned to the PO4(3-) ν3 antisymmetric stretching vibrations. Raman bands of paravauxite at 537, 570, 609 and 643 cm(-1) are assigned to the ν4 PO4(3-) bending modes whilst the Raman bands at 393 and 420 cm(-1) are due to the ν2 PO4(3-) bending modes. The Raman spectral profile of paravauxite in the hydroxyl stretching region is broad with component bands resolved at 3086, 3215, 3315, 3421, 3505 and 3648 cm(-1). Vibrational spectroscopy enables the assessment of the molecular structure of paravauxite to be undertaken. PMID:23973599

  10. Ts8 scorpion toxin inhibits the Kv4.2 channel and produces nociception in vivo.

    PubMed

    Pucca, Manuela Berto; Cerni, Felipe Augusto; Cordeiro, Francielle Almeida; Peigneur, Steve; Cunha, Thiago Mattar; Tytgat, Jan; Arantes, Eliane Candiani

    2016-09-01

    The venom from the scorpion Tityus serrulatus (Ts) has been extensively studied mainly because of its rich cocktail of neurotoxins. Neurotoxins are the major and the most known components based on their modulation of voltage-gated ion channels. Until now, electrophysiological studies demonstrated that the Ts venom comprises toxins that affect Nav and Kv channels. However, although many studies have been conducted in this field, many peptides from Ts venom await further studies, including Ts8 toxin. Here we report the isolation and electrophysiological study of Ts8. The toxin Ts19 Frag-II was used as negative control. Ts8 demonstrates, among 20 tested channels, to be a selective modulator of Kv4.2 channels. Based on studies investigating the involvement of Kv4.2 on controlling nociception, we further investigated the modulation of pain by Ts8. Using intraplantar injections, Ts8 induced overt nociception (licking and lifting behaviors) and decreased the mechanical nociceptive threshold (hyperalgesia). Furthermore, the hyperalgesia was prolonged when intrathecal injections were performed. Independent of the severity, most of the victims stung by Ts scorpions report an intense and persistent pain as the major manifestation. The new role of Ts8 on nociception could explain, at least partially, this phenomenon. Additionally, our study also stresses the involvement of toxins specific to Nav channels and inflammatory mediators on the Ts painful sting. This work provides useful insights for a better understanding of the prolonged and intense pain associated with Ts envenoming for the development of specific therapies. PMID:27346450

  11. 78 FR 56921 - South Bay Salt Pond Restoration Project, Phase 2 (Ponds R3, R4, R5, S5, A1, A2W, A8, A8S, A19...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-16

    ... Fish and Wildlife Service South Bay Salt Pond Restoration Project, Phase 2 (Ponds R3, R4, R5, S5, A1... restoration of ponds R3, R4, R5, S5, A1, A2W, A8, A8S, A19, A20, and A21 at the Don Edwards National Wildlife... 2 of the South Bay Salt Pond Restoration Project and consists of restoring and enhancing over...

  12. A new uranyl niobate sheet in the cesium uranyl niobate Cs{sub 9}[(UO{sub 2}){sub 8}O{sub 4}(NbO{sub 5})(Nb{sub 2}O{sub 8}){sub 2}

    SciTech Connect

    Saad, S.; Obbade, S. Yagoubi, S.; Renard, C.; Abraham, F.

    2008-04-15

    A new cesium uranyl niobate, Cs{sub 9}[(UO{sub 2}){sub 8}O{sub 4}(NbO{sub 5})(Nb{sub 2}O{sub 8}){sub 2}] or Cs{sub 9}U{sub 8}Nb{sub 5}O{sub 41} has been synthesized by high-temperature solid-state reaction, using a mixture of U{sub 3}O{sub 8}, Cs{sub 2}CO{sub 3} and Nb{sub 2}O{sub 5}. Single crystals were obtained by incongruent melting of a starting mixture with metallic ratio=Cs/U/Nb=1/1/1. The crystal structure of the title compound was determined from single crystal X-ray diffraction data, and solved in the monoclinic system with the following crystallographic data: a=16.729(2) A, b=14.933(2) A, c=20.155(2) A{beta}=110.59(1){sup o}, P2{sub 1}/c space group and Z=4. The crystal structure was refined to agreement factors R{sub 1}=0.049 and wR{sub 2}=0.089, calculated for 4660 unique observed reflections with I{>=}2{sigma}(I), collected on a BRUKER AXS diffractometer with MoK{alpha} radiation and a CCD detector. In this structure the UO{sub 7} uranyl pentagonal bipyramids are connected by sharing edges and corners to form a uranyl layer {sub {infinity}}{sup 2}[U{sub 8}O{sub 36}] corresponding to a new anion-sheet topology, and creating triangular, rectangular and square vacant sites. The two last sites are occupied by Nb{sub 2}O{sub 8} entities and NbO{sub 5} square pyramids, respectively, to form infinite uranyl niobate sheets {sub {infinity}}{sup 2}[(UO{sub 2}){sub 8}O{sub 4}(NbO{sub 5})(Nb{sub 2}O{sub 8}){sub 2}]{sup 9-} stacking along the [010] direction. The Nb{sub 2}O{sub 8} entities result from two edge-shared NbO{sub 5} square pyramids. The Cs{sup +} cations are localized between layers and ensured the cohesion of the structure. The cesium cation mobility between the uranyl niobate sheets was studied by electrical measurements. The conductivity obeys the Arrhenius law in all the studied temperature domains. The observed low conductivity values with high activation energy may be explained by the strong connection of the Cs{sup +} cations to the infinite

  13. 8 CFR 287.4 - Subpoena.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... immigration officer who has been expressly delegated such authority as provided by 8 CFR 2.1 may issue a... evidence, or both, for use in any proceeding under this chapter I, other than under 8 CFR part 335, or any... than those arising under part 335 of this chapter, are set forth at 8 CFR 1003.35(b) and 1287.4....

  14. Neurobehavioral Evaluation System (NES): comparative performance of 2nd-, 4th-, and 8th-grade Czech children.

    PubMed

    Otto, D A; Skalik, I; House, D E; Hudnell, H K

    1996-01-01

    The Neurobehavioral Evaluation System was designed for field studies of workers, but many NES tests can be performed satisfactorily by children as young as 7 or 8 years old and a few tests, such as simple reaction time, can be performed by preschool children. However, little comparative data from children of different ages or grade levels are available. Studies of school children in the Czech Republic indicate that 2nd-grade children could perform the following NES tests satisfactorily: Finger Tapping, Visual Digit Span. Continuous Performance, Symbol-Digit Substitution, Pattern Comparison, and simpler conditions of Switching Attention. Comparative scores of boys and girls from the 2nd, 4th, and 8th grades and power analyses to estimate appropriate sample size were presented. Performance varied systematically with grade level and gender. Larger samples were needed with younger children to achieve comparable levels of statistical power. Gender comparisons indicated that boys responded faster, but made more errors than girls. PMID:8866533

  15. Nodeless superconducting gaps in Ca10(Pt4- δ As8)((Fe1- x Pt x )2As2)5 probed by quasiparticle heat transport

    NASA Astrophysics Data System (ADS)

    Qiu, Xun; He, LanPo; Hong, XiaoChen; Zhang, Zhen; Pan, Jian; Shen, XiaoPing; Feng, DongLai; Li, ShiYan

    2016-05-01

    The in-plane thermal conductivity of the iron-based superconductor Ca10(Pt4- δ As8)((Fe1- x Pt x )2As2)5 single crystal ("10-4-8", T c = 22 K) was measured down to 80 mK. In a zero field, the residual linear term κ 0/ T is negligible, suggesting the nodeless superconducting gaps in this multiband compound. In the magnetic fields, κ 0/ T increases rapidly, which mimics the multiband superconductor NbSe2 and LuNi2B2C with highly anisotropic gap. Such a field dependence of κ 0/ T is an evidence for the multiple superconducting gaps with quite different magnitudes or highly anisotropic gap. Compared with the London penetration depth results of the Ca10(Pt4- δ As8)((Fe1- x Pt x )2As2)5 ("10-3-8") compound, the 10-4-8 and 10-3-8 compounds may have a similar superconducting gap structure.

  16. 8 CFR 1101.4 - Registration procedure.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... officer under § 1101.3 is described in § 264.2 of 8 CFR chapter 1. (Secs. 101(a)(20), 103, 262, 264 of the... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Registration procedure. 1101.4 Section 1101... REGULATIONS PRESUMPTION OF LAWFUL ADMISSION § 1101.4 Registration procedure. The procedure for an...

  17. 8H-Chromeno[2′,3′:4,5]imidazo[2,1-a]isoquinoline

    PubMed Central

    Safarov, Saifidin; Voskressensky, Leonid G.; Bizhko, Oksana V.; Kulikova, Larisa N.; Khrustalev, Victor N.

    2010-01-01

    The title compound, C18H12N2O, comprises two aromatic fragments, viz., imidazo[2,1-a]isoquinoline and benzene, linked by oxygen and methyl­ene bridges. Despite the absence of a common conjugative system within the mol­ecule, it adopts an essentially planar conformation with an r.m.s. deviation of 0. 036 Å. In the crystal, due to this structure, mol­ecules form stacks along the b axis by π⋯π stacking inter­actions, with shortest C⋯C distances in the range 3.340 (4)–3.510 (4) Å. The mol­ecules are bound by inter­molecular C—H⋯O inter­actions within the stacks and C—H⋯π inter­actions between the stacks. PMID:21580448

  18. Effects of Er3+ doping on the long-persistent luminescence properties of Ba4(Si3O8)2:Eu2+ phosphor

    NASA Astrophysics Data System (ADS)

    Wang, Pengjiu; Xu, Xuhui; Qiu, Jianbei; Yu, Xue; Wang, Qi

    2014-09-01

    A greenish-blue long-persistent luminescence (LPL) material of Ba4(Si3O8)2:Eu2+,Er3+ was synthesized by traditional solid state reaction method. Compared to Eu2+ single-doped Ba4(Si3O8)2 phosphor, the Eu2+/Er3+ co-doped sample shows brighter and longer afterglow. Photoluminescence (PL) and long-persistent luminescence (LPL) results indicated that PL and LPL are from the same luminescent centers which are ascribed to the 4f65d1 → 4f7 transition of the Eu2+. The incorporation of Er3+ ions largely extends the thermoluminescence characteristics and evidently enhances the LPL behavior of the phosphor. Since the TL glow curve in the Eu2+/Er3+ co-doped sample phosphor is different from that of Er3+ single-doped sample, it is considered that Er3+ plays an important role in LPL behavior.

  19. 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

  20. Structure and IR spectroscopic behaviour of 1,8-bis-(dimethylamino)naphthalene 2,4-dinitroimidazolate

    NASA Astrophysics Data System (ADS)

    Głowiak, T.; Malarski, Z.; Sobczyk, L.; Grech, E.

    1987-04-01

    The crystal structure of 1,8-bis(dimethylamino)naphthalene (DMAN) 2,4-dinitroimidazolate, C 17H 20N 6O 4, has been determined by X-ray diffraction. The crystals are monoclinic, P21/ c, a = 13.426(4), b = 10.465(3), c = 15.915(4) », β = 126.12(4)°, Z = 4. The structure was solved by direct methods, and refined to an R value of 0.033 for 2291 non-zero independent amplitudes. The [NN⋯N] + bridges of 2.606(3) » with ∠NHN = 160(3)° are characterized by an asymmetric proton density distribution. The IR protonic absorption is located in two regions at about 650 and 1950 cm -1 showing relatively small intensity. The isotopic ratio ν(NHN/ν(NDN) for the low frequency region is almost unity. It seems that hydrogen bonds in protonated DMAN are characterized by a flat asymmetric single minimum potential for the proton motion.

  1. Natural Polymorphisms in Tap2 Influence Negative Selection and CD4∶CD8 Lineage Commitment in the Rat

    PubMed Central

    Tuncel, Jonatan; Haag, Sabrina; Yau, Anthony C. Y.; Norin, Ulrika; Baud, Amelie; Lönnblom, Erik; Maratou, Klio; Ytterberg, A. Jimmy; Ekman, Diana; Thordardottir, Soley; Johannesson, Martina; Gillett, Alan; Stridh, Pernilla; Jagodic, Maja; Olsson, Tomas; Fernández-Teruel, Alberto; Zubarev, Roman A.; Mott, Richard; Aitman, Timothy J.; Flint, Jonathan; Holmdahl, Rikard

    2014-01-01

    Genetic variation in the major histocompatibility complex (MHC) affects CD4∶CD8 lineage commitment and MHC expression. However, the contribution of specific genes in this gene-dense region has not yet been resolved. Nor has it been established whether the same genes regulate MHC expression and T cell selection. Here, we assessed the impact of natural genetic variation on MHC expression and CD4∶CD8 lineage commitment using two genetic models in the rat. First, we mapped Quantitative Trait Loci (QTLs) associated with variation in MHC class I and II protein expression and the CD4∶CD8 T cell ratio in outbred Heterogeneous Stock rats. We identified 10 QTLs across the genome and found that QTLs for the individual traits colocalized within a region spanning the MHC. To identify the genes underlying these overlapping QTLs, we generated a large panel of MHC-recombinant congenic strains, and refined the QTLs to two adjacent intervals of ∼0.25 Mb in the MHC-I and II regions, respectively. An interaction between these intervals affected MHC class I expression as well as negative selection and lineage commitment of CD8 single-positive (SP) thymocytes. We mapped this effect to the transporter associated with antigen processing 2 (Tap2) in the MHC-II region and the classical MHC class I gene(s) (RT1-A) in the MHC-I region. This interaction was revealed by a recombination between RT1-A and Tap2, which occurred in 0.2% of the rats. Variants of Tap2 have previously been shown to influence the antigenicity of MHC class I molecules by altering the MHC class I ligandome. Our results show that a restricted peptide repertoire on MHC class I molecules leads to reduced negative selection of CD8SP cells. To our knowledge, this is the first study showing how a recombination between natural alleles of genes in the MHC influences lineage commitment of T cells. PMID:24586191

  2. Photodegradation of 4-tert-butylphenol in aqueous solution by UV-C, UV/H2O2 and UV/S2O8(2-) system.

    PubMed

    Wu, Yanlin; Zhu, Xiufen; Chen, Hongche; Dong, Wenbo; Zhao, Jianfu

    2016-01-01

    The photolytic degradation of 4-tert-butylphenol (4-t-BP) in aqueous solution was investigated using three kinds of systems: UV-C directly photodegradation system, UV/H2O2 and UV/S2O8(2-) system. Under experimental conditions, the degradation rate of 4-t-BP was in the order: UV/S2O8(2-) > UV/H2O2 > UV-C. The reaction kinetics of UV/S2O8(2-) system were thoroughly investigated. The increase of S2O8(2-) concentration enhanced the 4-t-BP degradation rate, which was inhibited when the concentration of S2O8(2-) exceeded 4.0 mM. The highest efficacy in 4-t-BP degradation was obtained at pH 6.5. The oxidation rate of 4-t-BP could be accelerated by increasing the reaction temperature and irradiation intensity. The highest rate constant (kobs = 8.4 × 10(-2) min(-1)) was acquired when the reaction temperature was 45 °C. The irradiation intensity was measured by irradiation distance, and the optimum irradiation distance was 10 cm. Moreover, the preliminary mechanism of 4-t-BP degradation was studied. The bond scission of the 4-t-BP molecule occurred by the oxidation of SO4(•-), which dimerized and formed two main primary products. Under the conditions of room temperature (25 °C ± 1 °C) and low concentration of K2S2O8 (0.5 mM), 35.4% of total organic carbon (TOC) was removed after 8.5-h irradiation. The results showed that UV/S2O8(2-) system was effective for the degradation of 4-t-BP. PMID:26819047

  3. Superconductivity in Ca10(Ir4As8)(Fe2As2)5 with Square-Planar Coordination of Iridium

    PubMed Central

    Kudo, Kazutaka; Mitsuoka, Daisuke; Takasuga, Masaya; Sugiyama, Yuki; Sugawara, Kento; Katayama, Naoyuki; Sawa, Hiroshi; Kubo, Hiroaki S.; Takamori, Kenta; Ichioka, Masanori; Fujii, Tatsuo; Mizokawa, Takashi; Nohara, Minoru

    2013-01-01

    We report the unprecedented square-planar coordination of iridium in the iron iridium arsenide Ca10(Ir4As8)(Fe2As2)5. This material experiences superconductivity at 16 K. X-ray photoemission spectroscopy and first-principles band calculation suggest Ir(II) oxidation state, which yields electrically conductive Ir4As8 layers. Such metallic spacer layers are thought to enhance the interlayer coupling of Fe2As2, in which superconductivity emerges, thus offering a way to control the superconducting transition temperature. PMID:24173038

  4. (2R)-4-Oxo-4[3-(Trifluoromethyl)-5,6-diihydro:1,2,4}triazolo[4,3-a}pyrazin-7(8H)-y1]-1-(2,4,5-trifluorophenyl)butan-2-amine: A Potent, Orally Active Dipeptidyl Peptidase IV Inhibitor for the Treatment of Type 2 Diabetes

    SciTech Connect

    Kim, D.; Wang, L.; Beconi, M.; Eiermann, G.; Fisher, M.; He, H.; Hickey, G.; Kowalchick, Jennifer; Leiting, Barbara; Lyons, K.; Marsilio, F.; McCann, F.; Patel, R.; Petrov, A.; Scapin, G.; Patel, S.; Roy, R.; Wu, J.; Wyvratt, M.; Zhang, B.; Zhu, L.; Thornberry, N.; Weber, A.

    2010-11-10

    A novel series of {beta}-amino amides incorporating fused heterocycles, i.e., triazolopiperazines, were synthesized and evaluated as inhibitors of dipeptidyl peptidase IV (DPP-IV) for the treatment of type 2 diabetes. (2R)-4-Oxo-4-[3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-1-(2,4,5-trifluorophenyl)butan-2-amine (1) is a potent, orally active DPP-IV inhibitor (IC{sub 50} = 18 nM) with excellent selectivity over other proline-selective peptidases, oral bioavailability in preclinical species, and in vivo efficacy in animal models. MK-0431, the phosphate salt of compound 1, was selected for development as a potential new treatment for type 2 diabetes.

  5. Biochemical and histological responses in rainbow trout (Oncorhynchus mykiss) exposed to 2,3,4,7,8-pentachlorodibenzofuran

    SciTech Connect

    Brown, S.B.; Evans, R.E.; Lockhart, W.L.; Delorme, P.D.; Ward, F.J.; Muir, D.C.G.

    1998-01-01

    Rainbow trout were given an intraperitoneal injection of corn oil containing 0 or 8.8 nmol (3 {micro}g) [{sup 14}C]2,3,4,7,8-pentachlorodibenzofuran (P{sub 5}CDF)/kg and were then held on a light cycle that induced spawning 10 months later. At 5- to 6-week intervals, blood samples were collected to monitor plasma levels of 17{beta}-estradiol (E{sub 2}), testosterone (T), thyroxine (T{sub 4}), 3,5,3{prime}-triiodo-L-thyronine (T{sub 3}), and calcium; packed cell volume (PCV); and differential blood cell counts. Fish were sacrificed after spawning to examine tissue P{sub 5}CDF concentration, liver ethoxyresorufin-O-deethylase (EROD), liver vitamins (retinoids and tocopherol), histology (liver, thyroid), and growth parameters. The P{sub 5}CDF injections produced tissue 2,3.7,8-tetrachlorodibenzo-p-dioxin toxic equivalent concentrations comparable to those reported in salmonids from contaminated areas. Highest P{sub 5}CDF concentrations occurred in gut and liver, but muscle accounted for the greatest proportion of the dose. Plasma hormone and calcium concentrations followed predicted seasonal patterns in both control and exposed fish. PCV was unchanged by repeated blood sampling but differential blood cell counts showed adaptive responses to blood removal. The P{sub 5}CDF exposure caused transient reductions in circulating lymphocytes and elevated EROD. Additionally, P{sub 5}CDF increased liver size and depleted retinoid stores in male fish. Liver histology, somatic growth, and gonadal development were unaltered by P{sub 5}CDF during the first reproductive cycle after exposure.

  6. A 0.8-4.2 GHz monolithic all-digital PLL based frequency synthesizer for wireless communications

    NASA Astrophysics Data System (ADS)

    Yuanxin, Zhao; Yuanpei, Gao; Wei, Li; Ning, Li; Junyan, Ren

    2015-01-01

    A 0.8-4.2 GHz monolithic all-digital PLL based frequency synthesizer for wireless communications is successfully realized by the 130 nm CMOS process. A series of novel methods are proposed in this paper. Two band DCOs with high frequency resolution are utilized to cover the frequency band of interest, which is as wide as 2.5 to 5 GHz. An overflow counter is proposed to prevent the “pulse-swallowing” phenomenon so as to significantly reduce the locking time. A NTW-clamp digital module is also proposed to prevent the overflow of the loop control word. A modified programmable divider is presented to prevent the failure operation at the boundary. The measurement results show that the output frequency range of this frequency synthesizer is 0.8-4.2 GHz. The locking time achieves a reduction of 84% at 2.68 GHz. The best in-band and out-band phase noise performances have reached -100 dBc/Hz, and -125 dBc/Hz respectively. The lowest reference spur is -58 dBc.

  7. 1,5,2,4,6,8-Dithiatetrazocine. Synthesis, computation, crystallography and voltammetry of the parent heterocycle.

    PubMed

    Moock, Klaus H; Wong, Ken M; Boeré, René T

    2011-11-21

    The prototypal 1,5,2,4,6,8-dithiatetrazocine has been synthesized for the first time by two routes: reaction of 1,2,3,5-dithiadiazolium chloride with N,N,N'-tris(trimethylsilyl)formamidine in acetonitrile and reaction of 1,2,3,5-dithiadiazolyl radical with dioxygen in solution. Yields are low but single crystals could be obtained for an X-ray crystal structure determination which shows it to have the planar delocalized structure predicted by B3LYP/6-311+G(2d,p) hybrid DFT calculations. The crystal structure is strongly reminiscent of that of benzene in the same Pbca space group. Aromaticity is demonstrated by a (1)H NMR chemical shift of +9.70 ppm indicative of diamagnetic ring shielding and an intense low-energy optical absorption with λ(max) = 349 nm (MeOH). The voltammetric behaviour of the title compound is compared with that of 1,3λ(4)δ(2),5,2,4-trithiadiazepine; both resist electrochemical oxidation and reduction over a wide potential range as is typical for aromatic heterocycles. PMID:21956480

  8. A novel octanuclear vanadium(V) oxide cluster complex having an unprecedented neutral V8O20 core functionalized with 4,4'-di-tert-butyl-2,2'-bipyridine.

    PubMed

    Kodama, Shintaro; Taya, Nobuto; Ishii, Youichi

    2014-03-17

    A novel octanuclear vanadium(V) oxide cluster complex, [V8O20(4,4'-(t)Bubpy)4] (1), was synthesized and characterized by single-crystal X-ray structure analysis to reveal that 1 has an unprecedented neutral V8O20 core. An unexpected interconversion between 1 and the methoxo(oxo)vanadium(V) cluster complex, [V4O8(OMe)4(4,4'-(t)Bubpy)2] (2), was observed upon changes in the solvent systems. PMID:24559114

  9. High-capacity Li2Mn0.8Fe0.2SiO4/carbon composite nanofiber cathodes for lithium-ion batteries

    NASA Astrophysics Data System (ADS)

    Zhang, Shu; Li, Ying; Xu, Guanjie; Li, Shuli; Lu, Yao; Toprakci, Ozan; Zhang, Xiangwu

    2012-09-01

    Li2MnSiO4 has been considered as a promising cathode material with an extremely high theoretically capacity of 332 mAh g-1. However, due to its low intrinsic conductivity and poor structural stability, only about half of the theoretical capacity has been realized in practice and the capacity decays rapidly during cycling. To realize the high capacity and improve the cycling performance, Li2Mn0.8Fe0.2SiO4/carbon composite nanofibers were prepared by the combination of iron doping and electrospinning. X-ray diffraction, scanning electron microscope, and transmission electronic microscope were applied to characterize the Li2Mn0.8Fe0.2SiO4/carbon nanofibers. It was found that Li2Mn0.8Fe0.2SiO4 nanoparticles were embedded into continuous carbon nanofiber matrices, which formed free-standing porous mats that could be used as binder-free cathodes. The iron doping improved the conductivity and purity of the active material, and the carbon nanofiber matrix facilitated ion transfer and charge diffusion. As a result, Li2Mn0.8Fe0.2SiO4/carbon nanofiber cathodes showed promising improvement on reversible capacity and cycling performance.

  10. Microwave Dielectric Properties of Ba0.2Sr0.8La4Ti4O15 Ceramic with La2O3-B2O3-TiO2 Doping

    NASA Astrophysics Data System (ADS)

    Li, Ying-xiang; Si, Feng; Tang, Bin; Wang, Ya; Zhang, Shu-ren

    2016-02-01

    The effects of La2O3-B2O3-TiO2 (LBT) glass addition on the phase composition, microstructure, and microwave dielectric properties of Ba0.2Sr0.8La4Ti4O15 (BSLT) ceramic were investigated in this study. X-ray diffraction results showed that a small amount of SrLaBO4 secondary phase was formed in the LBT-doped BSLT ceramics. Scanning electron microscopy indicated that addition of LBT glass restrained grain growth of the main phase. Samples doped with LBT showed strong promotion of both ɛ r and Q × f values. Typically, the LBT (La2O3:B2O3:TiO2 = 1:0.5:0.5)-doped Ba0.2Sr0.8La4Ti4O15 ceramic sintered at 1550°C for 3 h in air exhibited good microwave dielectric properties of ɛ r = 50.7, Q × f = 72,700 GHz, and τ f = -7.3 ppm/°C.

  11. One-step catalytic asymmetric synthesis of all-syn deoxypropionate motif from propylene: Total synthesis of (2R,4R,6R,8R)-2,4,6,8-tetramethyldecanoic acid.

    PubMed

    Ota, Yusuke; Murayama, Toshiki; Nozaki, Kyoko

    2016-03-15

    In nature, many complex structures are assembled from simple molecules by a series of tailored enzyme-catalyzed reactions. One representative example is the deoxypropionate motif, an alternately methylated alkyl chain containing multiple stereogenic centers, which is biosynthesized by a series of enzymatic reactions from simple building blocks. In organic synthesis, however, the majority of the reported routes require the syntheses of complex building blocks. Furthermore, multistep reactions with individual purifications are required at each elongation. Here we show the construction of the deoxypropionate structure from propylene in a single step to achieve a three-step synthesis of (2R,4R,6R,8R)-2,4,6,8-tetramethyldecanoic acid, a major acid component of a preen-gland wax of the graylag goose. To realize this strategy, we focused on the coordinative chain transfer polymerization and optimized the reaction condition to afford a stereo-controlled oligomer, which is contrastive to the other synthetic strategies developed to date that require 3-6 steps per unit, with unavoidable byproduct generation. Furthermore, multiple oligomers with different number of deoxypropionate units were isolated from one batch, showing application to the construction of library. Our strategy opens the door for facile synthetic routes toward other natural products that share the deoxypropionate motif. PMID:26908873

  12. Electrical transport properties of dense bulk YBa 2Cu 4O 8 produced by hot isostatic pressing

    NASA Astrophysics Data System (ADS)

    Andersson, B. M.; Sundqvist, B.; Niska, J.; Loberg, B.; Easterling, K.

    1990-10-01

    Highly dense sintered YBa 2Cu 4O 8 has been produced by hot isostatic pressing (HIP). The electrical resistivity ϱ of this material has been measured as a function of temperature T and pressure ϱ in the range 40-650 K and 0-0.7 GPa. Both the temperature dependence and the pressure dependence of ϱ are found to be well described by a model based on the standard Bloch-Grüneisen theory. It is pointed out that ϱ is liner in T only under isobaric conditions, while ϱ is strongly nonlinear in all high- Tc superconductors under isochoric (constant volume) conditions. The critical current density of the material is 900 A/cm 2 at 4 K, while the resistivity is 630 μΩ cm at 294 K.

  13. Selective detection of 2,4,6-trinitrophenol based on a fluorescent nanoscale bis(8-hydroxyquinoline) metal complex.

    PubMed

    Lv, Xiao-Jun; Qi, Liang; Gao, Xiang-Yu; Wang, Huan; Huo, Yuan; Zhang, Zhi-Qi

    2016-04-01

    The reliable and accurate detection of explosives such as 2,4,6-trinitrophenol (TNP) and 2,4,6-trinitrotoluene (TNT) is in high demand for homeland security and public safety. Although extremely high sensitivity towards TNT has been demonstrated, detection of TNP remains a challenge. In this work, a fluorescent nanoscale complex composed of bis(8-hydroxyquinoline) and Al(3+) ions has been prepared, characterized and applied in detection of TNP. This complex exhibits the ability to sense the nitro explosive TNP via a fluorescence quenching mechanism with high selectivity. A simple paper test system for the rapid monitoring of TNP was also investigated. The results show that Bhq-Al is a quite ideal sensing material for trace-level detection of TNP. PMID:26838414

  14. 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.

  15. Paramagnetic and Glass States in Superconductive YBa2Cu4O8 Ceramics of Sub-Micron Scale Grains

    NASA Astrophysics Data System (ADS)

    Deguchi, Hiroyuki; Oniki, Ryo; Mito, Masaki; Takagi, Seishi; Hagiwara, Makoto

    2005-08-01

    The YBa2Cu4O8 ceramic superconductor shows successive superconducting transitions and is considered as a random Josephson-coupled networks of 0- and π-junctions. We have investigated the magnetic properties in order to clarify the inter-grain glass and Paramagnetic Meissner behavior at low field. A thermodynamically stable chiral-glass state in the field cooled-cooling and a metastable paramagnetic one in the field cooled-warming are observed below the inter-grain transition temperature. The results agree well the so-called d-wave mechanism leading to Paramagnetic Meissner effects in ceramic high-Tc superconductors.

  16. Synthesis, spectral features and biological activity of some novel hetarylazo dyes derived from 8-chloro-4-hydroxyl-2-quinolone

    NASA Astrophysics Data System (ADS)

    Yahyazadeh, Asieh; Yousefi, Hessamoddin

    2014-01-01

    In this study, 8-chloro-4-hydroxyl-2-quinolone was synthesized from cyclocondensation of corresponding dianilide and subsequently used as a potent coupling component with some diazotized heterocyclic amines. These compounds were characterized by UV-vis, FT-IR, 1H NMR spectroscopic techniques and elemental analysis. Absorption spectra of these dyes were measured in six polar solvents and discussed with respect to the nature of solvents and substituted groups. The effects of acid, base, temperature and concentration on the visible absorption spectra of the dyes were reported. In addition, the antimicrobial activity of the dyes was explored in detail.

  17. Synthesis and anticonvulsant evaluation of some new 2,3,8-trisubstituted-4(3H)-quinazoline derivatives.

    PubMed

    El-Azab, Adel S; Eltahir, Kamal E H

    2012-01-01

    A new series of 2,3,8-trisubstituted-4(3H)-quinazoline derivatives were synthesized, evaluated for their anticonvulsant activity against electrically (MES) and chemically (PTZ, picrotoxin and Strychnine) induced seizures and compared with the standard drugs methaqualone and sodium valproate. Compounds 3, 17 and 22 proved to be the most potent compounds of this series with relatively low neurotoxicity and low toxicity in the median lethal dose test as compared with the reference drugs. The obtained results showed that the most active compounds could be useful as a template for future design, modification and investigation to produce more active analogs. PMID:22137344

  18. 4,10-Dinitro-2,6,8,12-tetraoxa-4,10-diazatetracyclo[5.5.0.05,903,11]dodecane Synthesis

    NASA Astrophysics Data System (ADS)

    Maksimowski, Paweł; Gołofit, Tomasz

    2013-07-01

    4,10-Dinitro-2,6,8,12-tetraoxa-4,10-diazatetracyclo[5.5.0.05,903,11]dodecane (TEX) was obtained by nitrolysis of 1,4-diformyl-2,3,5,6-tetrahydroxypiperazine reaction using a mixture of fuming nitric acid and concentrated sulfuric acid. The optimal process temperature was 54-56°C. The yield of the synthesis depends inter alia on the rate the reactants are introduced into the reaction medium and on the time of conditioning of the reaction mixture. A maximal yield of ca. 40% was achieved at the reactant addition time of 2 h and conditioning time of 2 h. None of the other nitrating mixtures examined proved superior to the conventional nitrating mixture. The product was examined by high-performance liquid chromatography (HPLC), nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), and differential scanning calorimetry (DSC) techniques and the results are reported.

  19. Synthesis, molecular structure and characterization of allylic derivatives of 6-amino-3-methyl-1,2,4-triazolo[3,4-f][1,2,4]-triazin-8(7H)-one.

    PubMed

    Hwang, Long-Chih; Jane, Shin-Yi; Lai, Hsing-Yi; Tu, Chun-Hsien; Lee, Gene-Hsiang

    2006-01-01

    1-Allyl- (2) and 7-allyl-6-amino-3-methyl-1,2,4-triazolo[3,4-f][1,2,4]triazin-8(7H)-one (3) were obtained via the 18-crown-6-ether catalyzed room temperature reaction of 6-amino-3-methyl-1,2,4-triazolo[3,4-f][1,2,4]triazin-8(7H)-one (1) with potassium carbonate and allyl bromide in dry acetone. The structures of these two derivatives were verified by 2D-NMR measurements, including gHSQC and gHMBC measurements. The minor compound 2 may possess aromatic character. A single crystal X-ray diffraction experiment indicated that the major compound 3 crystallizes from dimethyl sulfoxide in the monoclinic space group P2(1)/n and its molecular structure includes an attached dimethylsulfoxide molecule, resulting in the molecular formula C(10)H(16)N(6)O(2)S. Molecular structures of 3 are linked by extensive intermolecular N-H...N hydrogen bonding [graph set C(1)(1)(7)]. 1 Each molecule is attached to the dimethyl sulfoxide oxygen via N-H...O intermolecular hydrogen bonding. The structure is further stabilized by pi-pi stacking interactions. PMID:17962777

  20. Crystal structure of 8-eth-oxy-3-(4-nitro-phen-yl)-2H-chromen-2-one.

    PubMed

    Walki, Shashikanth; Naveen, S; Kenchanna, S; Mahadevan, K M; Kumara, M N; Lokanath, N K

    2015-11-01

    In the title compound, C17H13NO5, the coumarin ring system is essentially planar (r.m.s. deviation = 0.008 Å). The nitro-phenyl ring makes a dihedral angle of 25.27 (9)° with the coumarin ring plane. The nitro group is almost coplanar with the phenyl ring to which it is attached, making a dihedral angle of 4.3 (3)°. The eth-oxy group is inclined to the coumarin ring plane by 4.1 (2)°. Electron delocalization was found at the short bridging C-C bond with a bond length of 1.354 (2) Å. In the crystal, mol-ecules are linked via C-H⋯O hydrogen bonds, forming sheets in the bc plane. The sheets are linked via π-π stacking [centroid-centroid distances = 3.5688 (13) and 3.7514 (13) Å], forming a three-dimensional structure. PMID:26594565

  1. Raman and infrared spectroscopic characterization of the phosphate mineral paravauxite Fe2+Al2(PO4)2(OH)28H2O

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; Scholz, Ricardo; Lópes, Andrés; Xi, Yunfei; Gobac, Željka Žigovečki; Horta, Laura Frota Campos

    2013-12-01

    We have undertaken a vibrational spectroscopic study of paravauxite the Siglo XX mine, Bustillo Province, northern of Potosí department, Bolivia. This mine is important source for rare and unusual secondary phosphate minerals and is the type locality for a number of rare phosphates such as vauxite, sigloite, metavauxite and for jeanbandyite. The chemical formula of the studied sample was determined as Fe0.952+,(Al0.07)Σ1.02(Al)2.09(PO4)1.97(OH)1.98·7.90(H2O). The Raman spectrum is dominated by an intense Raman band at 1020 cm-1 assigned to the PO43-ν1 symmetric stretching mode. Low intensity Raman bands found at 1058, 1115 and 1148 cm-1 are assigned to the PO43-ν3 antisymmetric stretching vibrations. Raman bands of paravauxite at 537, 570, 609 and 643 cm-1 are assigned to the ν4PO43- bending modes whilst the Raman bands at 393 and 420 cm-1 are due to the ν2PO43- bending modes. The Raman spectral profile of paravauxite in the hydroxyl stretching region is broad with component bands resolved at 3086, 3215, 3315, 3421, 3505 and 3648 cm-1. Vibrational spectroscopy enables the assessment of the molecular structure of paravauxite to be undertaken.

  2. Volumetric Properties of the Mixture Thiolane 1,1-dioxide C4H8O2S + C6H14O4 3,6-Dioxaoctane-1,8-diol (VMSD1111, LB5084_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Thiolane 1,1-dioxide C4H8O2S + C6H14O4 3,6-Dioxaoctane-1,8-diol (VMSD1111, LB5084_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  3. Volumetric Properties of the Mixture Thiolane 1,1-dioxide C4H8O2S + C6H14O4 3,6-Dioxaoctane-1,8-diol (VMSD1212, LB5088_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Thiolane 1,1-dioxide C4H8O2S + C6H14O4 3,6-Dioxaoctane-1,8-diol (VMSD1212, LB5088_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  4. Design, Synthesis and Biological Evaluation of 5-Oxo-1,4,5,6,7,8 Hexahydroquinoline Derivatives as Selective Cyclooxygenase-2 Inhibitors

    PubMed Central

    Zarghi, Afshin; Sabakhi, Iman; Topuzyan, Vigen; Hajimahdi, Zahra; Daraie, Bahram

    2014-01-01

    A group of regioisomeric 5-oxo-1,4,5,6,7,8 hexahydroquinoline derivatives possessing a COX-2 SO2Me pharmacophore at the para position of the C-2 or C-4 phenyl ring, in conjunction with a C-4 or C-2 phenyl (4-H) or substituted-phenyl ring (4-F,4-Cl,4-Br,4-OMe,4-Me, 4-NO2), were designed for evaluation as selective cyclooxygenase-2 (COX-2) inhibitors. These target 5-oxo-1,4,5,6,7,8 hexahydroquinolines were synthesized via a Hansch condensation reaction. In vitro COX-1/COX-2 isozyme inhibition structure-activity studies identified 7,8-dihydro- 7,7-dimethyl-2-(4-methoxyphenyl)-4-(4-(methylsulfonyl)phenyl)quinolin-5(1H,4H,6H)- one (9c) as a potent COX-2 inhibitor (IC50 = 0.17 M) with a high COX-2 selectivity index (S.I. = 97.6) comparable to the reference drug celecoxib (COX-2 IC50 = 0.05 mM; COX-2 S.I= 405). A molecular modeling study where 9c was docked in active site of COX-2 showed that the p-SO2Me substituent on the C-2 phenyl ring is inserted into the secondary COX-2 binding site. The structure activity data acquired indicate that the position of the COX-2 SO2Me pharmacophore and type of substituent are important for COX-2 inhibitory activity. PMID:24711830

  5. Interleukin-2 Enhances the Regulatory Functions of CD4(+)T Cell-Derived CD4(-)CD8(-) Double Negative T Cells.

    PubMed

    Cong, Min; Liu, Tianhui; Tian, Dan; Guo, Hongbo; Wang, Ping; Liu, Kai; Lin, Jun; Tian, Yue; Shi, Wen; You, Hong; Jia, Jidong; Zhang, Dong

    2016-08-01

    CD4(+) T cells can be converted to CD4(-)CD8(-) double negative T cells (DN T cells) under appropriate conditions, and IL-2 enhanced the conversion. Here, we investigated the effect of IL-2 on the proliferation and function of converted DN T cells in vitro and in vivo. DN T cells were hyporesponsive when restimulated by mature dendritic cells (mDCs), IL-2 completely restored their responsiveness in vitro. In addition, IL-2 increased the resistance of DN T cells to apoptosis in vivo. DN T cells profoundly inhibited the proliferation of CD4(+)CD25(-) T effector cells triggered by mDCs in vitro, and this suppression was further enhanced by IL-2. Adoptively transferring of DN T cells, in combination with IL-2, inhibited the proliferation and enhanced apoptosis of alloreactive CD4(+) T cells, which resulted in significant prolongation of skin allograft survival time. Perforin plays a key role in the enhancement of DN T cells immune regulation by IL-2. In conclusion, we elucidated that IL-2 promoted DN T cell proliferation and suppressive function. The combination of DN T cells and exogenous IL-2 may represent a novel therapy in the clinical setting to prevent allograft rejection and induce immune tolerance. PMID:27135902

  6. Surface vibrational Raman modes of In:Si(111)(4 ×1 ) and (8 ×2 ) nanowires

    NASA Astrophysics Data System (ADS)

    Speiser, E.; Esser, N.; Wippermann, S.; Schmidt, W. G.

    2016-08-01

    High-resolution Raman spectroscopy at low frequencies (<100 cm-1) is used to reinvestigate and identify the surface phonons localized in the first atomic layers of In:Si(111)(4 ×1 ) and (8 ×2 ). The frequency and symmetry of low-energy surface phonons are strongly related to surface structure. The measured phonons are assigned to characteristic modes of the quasi-one-dimensional indium nanowires on Si(111) by means of density-functional theory calculations and symmetry considerations. It is found that the low-temperature (8 ×2 ) and the room-temperature (4 ×1 ) phases of the In:Si(111) surface are characterized by distinct sets of phonon modes. Strong modifications in Raman spectra upon the phase transition are, on the one hand, related to backfolding induced by symmetric quadruplication of the surface unit cell and, on the other hand, to structural changes within the surface unit cell. These are indications for two distinct structural phases, supporting the first-order transition scenario. The characteristic structural changes are thus verified in detail.

  7. Spectroscopy and structure of quadruply bonded complexes under extreme pressure (Re sub 2 X sub 8 sup 2 minus , Mo sub 2 Cl sub 4 (PMe sub 3 ) sub 4 )

    SciTech Connect

    Morris, D.E.; Tait, C.D.; Dyer, R.B.; Schoonover, J.R.; Hopkins, M.D.; Sattelberger, A.P.; Woodruff, W.H. Univ. of Pittsburgh, PA )

    1990-09-05

    Application of pressure (up to 150 kbar, where 1 kbar = 986.9 atm = 0.1 GPa) to solutions of Re{sub 2}X{sub 8}{sup 2{minus}} (X = F, Cl, Br) and Mo{sub 2}Cl{sub 4}(PMe{sub 3}){sub 4} results in smooth, continuous changes in experimental observables related to metal-metal bond length and, for the Re complexes, torsional angle (X-Re-Re-X dihedral angle). Resonance Raman studies show that increasing pressure engenders an increase in the frequency of the metal-metal stretching mode for all of the species studied, and this change is empirically correlated with a decrease in metal-metal bond length. Large red shifts in the energy of the {sup 1}({delta} {yields} {delta}*) transitions with increased pressure for Re{sub 2}Br{sub 8}{sup 2{minus}} and Re{sub 2}Cl{sub 8}{sup 2{minus}}, in contrast to the relative insensitivity of Re{sub 2}F{sub 8}{sup 2{minus}} absorption and Mo{sub 2}Cl{sub 4}(PMe{sub 3}){sub 4} fluorescence transitions, imply a tendency for the former complexes to distort torsionally from an eclipsed configuration toward a staggered configuration due to pressure-induced steric repulsion of the chloride and bromide ligands. Integrated absorption intensities further show that, at higher pressures, even Re{sub 2}F{sub 8}{sup 2{minus}} undergoes some torsional distortion, whereas the steric repulsion of adjacent phosphines located at a 90{degree} dihedral angle on opposite Mo atoms prevents Mo{sub 2}Cl{sub 4}(PMe{sub 3}){sub 4} from distorting along the torsional coordinate. 28 refs., 7 figs., 1 tab.

  8. Structure-activity relationships and molecular studies of novel arylpiperazinylalkyl purine-2,4-diones and purine-2,4,8-triones with antidepressant and anxiolytic-like activity.

    PubMed

    Zagórska, Agnieszka; Kołaczkowski, Marcin; Bucki, Adam; Siwek, Agata; Kazek, Grzegorz; Satała, Grzegorz; Bojarski, Andrzej J; Partyka, Anna; Wesołowska, Anna; Pawłowski, Maciej

    2015-06-01

    A novel series of arylpiperazinylalkyl purine-2,4-diones (4-27) and purine-2,4,8-triones (31-38) was synthesized and tested to evaluated their affinity for the serotoninergic (5-HT1A, 5-HT6, 5-HT7) and dopaminergic (D2) receptors. Compounds with purine-2,4-dione nucleus generally had affinity values higher than the corresponding purine-2,4,8-trione compounds. A spectrum of receptor activities was observed for compounds with a substituent at the 7-position of the imidazo[2,1-f]purine-2,4-dione system and some potent 5-HT1A (18, 25), 5-HT7 (14) and mixed 5-HT1A/5-HT7 (8, 9) receptor ligands with additional affinity for dopamine D2 receptors (15) has been identified. Moreover, docking studies proved that a substituent at the 7-position of 1,3-dimethyl-(1H,8H)-imidazo[2,1-f]purine-2,4-dione could be essential for receptor affinity and selectivity, especially towards 5-HT1A and 5-HT7. The results of the preliminary pharmacological in vivo studies of selected derivatives of 1,3-dimethyl-(1H,8H)-imidazo[2,1-f]purine-2,4-dione, including 9 as a potential anxiolytic, 8 and 15 as potential antidepressants, and 18 and 25 as potential antidepressant and anxiolytic agents. PMID:25965777

  9. Dissociation, absorption and ionization of some important sulfur oxoanions (S2On2- n = 2, 3, 4, 6, 7 and 8)

    NASA Astrophysics Data System (ADS)

    Abedi, M.; Farrokhpour, H.; Farnia, S.; Chermahini, A. Najafi

    2015-08-01

    In this work, a systematic theoretical study was performed on the dissociation, absorption and ionization of several important sulfur oxoanions (S2On2- (n = 2, 3, 4, 6, 7 and 8)). ΔEelec (thermal corrected energy), ΔH° and ΔG° of the dissociation reactions of the oxoanions to their radical monoanions were calculated using combined computational levels of theories such as Gaussian-3 (G3) and a new version of complete basis set method (CBS-4M) in different environments including gas phase, microhydrated in gas phase and different solvents. Calculations showed S2O72- is the most stable anion against the dissociation to its radical monoanions (SO4-rad + SO3-rad). It was also found that S2O42- has more tendency to dissociate to its radical anions (SO2-rad + SO2-rad) compared to the other anions. The absorption spectra of the anions were also calculated using the time-dependent density functional theory (TD-DFT) employing M062X functional. The effect of microhydration and electrostatic field of solvent on the different aspects (intensity, energy shift and assignment) of the absorption spectra of these anions were also discussed. It was observed that both hydrogen bonding and electrostatic effect of water increases the intensity of the absorption spectrum compared to the gas phase. Effect of microhydration in shifting the spectra to the shorter wavelength is considerably higher than the effect of electrostatic field of water. Finally, several gas phase ionization energies of the anions were calculated using the symmetry-adapted cluster-configuration interaction methodology (SAC-CI) and found that the first electron detachment energies of S2O22-, S2O32- and S2O42- are negative. Natural bonding orbital (NBO) calculations were also performed to assign the electron detachment bands of the anions.

  10. Series of isostructural planar lanthanide complexes [Ln(III)4(mu3-OH)2(mdeaH)2(piv)8] with single molecule magnet behavior for the Dy4 analogue.

    PubMed

    Abbas, Ghulam; Lan, Yanhua; Kostakis, George E; Wernsdorfer, Wolfgang; Anson, Christopher E; Powell, Annie K

    2010-09-01

    A series of five isostructural tetranuclear lanthanide complexes of formula [Ln(4)(mu(3)-OH)(2)(mdeaH)(2)(piv)(8)], (mdeaH(2) = N-methyldiethanolamine; piv = pivalate; Ln = Tb (1), Dy (2), Ho (3), Er (4), and Tm (5)) have been synthesized and characterized. These clusters have a planar "butterfly" Ln(4) core. Magnetically, the Ln(III) ions are weakly coupled in all cases; the Dy(4) compound 2 shows Single Molecule Magnet (SMM) behavior. PMID:20704320

  11. 40 CFR 721.10004 - 2-Butenoic acid, 4,4′-[(dibutylstannylene)bis(oxy)]bis[4-oxo-, (2Z,2′Z)-, di-C8-10-isoalkyl...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-, (2Z,2â²Z)-, di-C8-10-isoalkyl esters, C9-rich. 721.10004 Section 721.10004 Protection of Environment...-, (2Z,2′Z)-, di-C8-10-isoalkyl esters, C9-rich. (a) Chemical substance and significant new uses subject...)-, di-C8-10-isoalkyl esters, C9-rich (PMN P-98-1181; CAS No. 247041-56-1) is subject to reporting...

  12. 40 CFR 721.10004 - 2-Butenoic acid, 4,4′-[(dibutylstannylene)bis(oxy)]bis[4-oxo-, (2Z,2′Z)-, di-C8-10-isoalkyl...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-, (2Z,2â²Z)-, di-C8-10-isoalkyl esters, C9-rich. 721.10004 Section 721.10004 Protection of Environment...-, (2Z,2′Z)-, di-C8-10-isoalkyl esters, C9-rich. (a) Chemical substance and significant new uses subject...)-, di-C8-10-isoalkyl esters, C9-rich (PMN P-98-1181; CAS No. 247041-56-1) is subject to reporting...

  13. Photoluminescence Properties of Na+(Ba2+) and Nb5+(P5+)-Doped Sr2.4Y0.2Eu0.2V2O8 Phosphors

    NASA Astrophysics Data System (ADS)

    Mu, Jing Jing; Zheng, Gan Hong; Dai, Zhen Xiang; Zhang, Lin Yun; Zhu, Ya Nan

    2016-05-01

    A series of Sr2.4Y0.2Eu0.2V2O8:xNa+(yBa2+) and Sr2.4Y0.2Eu0.2V2O8:zNb5+(mP5+) phosphors are synthesized by solid-state reaction method and the photoluminescence (PL) properties are investigated. All phosphors exhibit bright red emission centered at ˜619 nm. Na+ and Ba2+, as the sensitizers for the luminescence of Eu3+, are found to improve significantly the PL intensity of these phosphors. For the Sr2.4Y0.2Eu0.2V2O8:xNa+(yBa2+) samples, the emission intensity increases with Na+(Ba2+) doping, and the strongest intensity is achieved in the case when x is 0.09 and y is 0.15. The introduction of Nb(P)O4 3- reduces the non-radiative energy transfer between neighboring VO4 3- and results in the energy transfer between VO4 3- and Eu3+, and eventually leads to the enhancement of Eu3+ emission. Comparing the doping effect of between Na and Ba, and the effect between Nb and P, respectively, it is found that both Na and P doping largely tend to improve the emission intensity. The relevant mechanisms have been discussed.

  14. Photoluminescence Properties of Na+(Ba2+) and Nb5+(P5+)-Doped Sr2.4Y0.2Eu0.2V2O8 Phosphors

    NASA Astrophysics Data System (ADS)

    Mu, Jing Jing; Zheng, Gan Hong; Dai, Zhen Xiang; Zhang, Lin Yun; Zhu, Ya Nan

    2016-07-01

    A series of Sr2.4Y0.2Eu0.2V2O8: xNa+( yBa2+) and Sr2.4Y0.2Eu0.2V2O8: zNb5+(mP5+) phosphors are synthesized by solid-state reaction method and the photoluminescence (PL) properties are investigated. All phosphors exhibit bright red emission centered at ˜619 nm. Na+ and Ba2+, as the sensitizers for the luminescence of Eu3+, are found to improve significantly the PL intensity of these phosphors. For the Sr2.4Y0.2Eu0.2V2O8: xNa+( yBa2+) samples, the emission intensity increases with Na+(Ba2+) doping, and the strongest intensity is achieved in the case when x is 0.09 and y is 0.15. The introduction of Nb(P)O4 3- reduces the non-radiative energy transfer between neighboring VO4 3- and results in the energy transfer between VO4 3- and Eu3+, and eventually leads to the enhancement of Eu3+ emission. Comparing the doping effect of between Na and Ba, and the effect between Nb and P, respectively, it is found that both Na and P doping largely tend to improve the emission intensity. The relevant mechanisms have been discussed.

  15. Toxicity and disposition of 2,3,4,7,8-pentachlorodibenzofuran (4PeCDF) in the rhesus monkey (Macaca mulatta)

    SciTech Connect

    Brewster, D.W.; Elwell, M.R.; Birnbaum, L.S.

    1988-04-01

    The toxicity and disposition of 2,3,4,7,8-pentachlorodibenzofuran (4PeCDF), a ubiquitous and acutely toxic environmental contaminant, was examined in three adult male Rhesus monkeys administered a single iv dose of 34 micrograms (0.1 mumol)/kg. Within 20 min, 4PeCDF was eliminated from the blood and was distributed to the liver, skin, adipose, and muscle tissues. Excretion occurred primarily via the feces with a minimum whole body half-life approximately 38 days. Within 7-14 days after administration, the packed cell volume and serum triglyceride and bile acid concentrations were significantly increased while serum cholesterol, protein, and albumin concentrations were decreased relative to pretreatment levels. Thyroid hormone levels were also altered with an increase in TSH and a decrease in T3 and T4 concentrations. After 28 days, two monkeys began exhibiting alopecia, hyperkeratinization of the toe and finger nails, facial chloracne-like lesions, and loss of body weight. They subsequently died 40 and 48 days after treatment. Similar symptoms of toxicity were observed in the third animal 58 days after 4PeCDF administration, but this animal appeared to fully recover and was administered 4PeCDF orally and (3H)1,2,3,7,8-pentachloro-dibenzofuran (1PeCDF) dermally 238 days after the initial iv dose. In this animal, approximately 2% of an oral dose of (14C)-4PeCDF was absorbed from the stomach and small intestine in 6 hr and was distributed mainly to the muscle and skin and less than 99% of a dermal dose of 1PeCDF remained at the site of application. Pathological findings in the monkeys that died indicated hyperplastic and metaplastic changes in the gastric mucosa, the Meibomian glands of the eyelid, and the ceruminous glands of the ear. Regression of these lesions was present in the surviving animal.

  16. 8 CFR 1101.4 - Registration procedure.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... officer under § 1101.3 is described in § 264.2 of 8 CFR chapter 1. (Secs. 101(a)(20), 103, 262, 264 of the Immigration and Nationality Act, as amended; 8 U.S.C. 1101(a)(20), 1103, 1302, 1304) ....4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE...

  17. 1. Mono((8)annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

    SciTech Connect

    Boussie, T.R.

    1991-10-01

    A reproducible, high-yield synthesis of mono((8)annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono((8)annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

  18. 1. Mono([8]annulene)Uranium(4) half-sandwich complexes, 2. Novel syntheses of symmetrically substituted cyclooctatetetraenes

    SciTech Connect

    Boussie, T.R.

    1991-10-01

    A reproducible, high-yield synthesis of mono([8]annulene)uranium(4)dichloride (1) is reported, along with the X-ray crystal structural of the bis(pyridine) adduct. Metathesis reactions of the half-sandwich complex 1 with a variety of simple alkyl and alkoxy reagents failed to generate any isolable mono-ring complexes. Reactions of 1 with polydentate, delocalized anions did produce stable derivatives, including mono([8]annulene)uranium(4)bis(acetylacetonate) (4). An X-ray crystal structure of 4 is reported.

  19. Direct imaging of structural heterogeneity of the melt-spun Fe{sub 85.2}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 0.8} alloy

    SciTech Connect

    Sato, Kazuhisa Takenaka, Kana; Makino, Akihiro; Hirotsu, Yoshihiko

    2015-06-15

    A structural heterogeneity of the melt-spun Fe{sub 85.2}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 0.8} alloy has been studied by spherical aberration (C{sub s}) corrected high-resolution transmission electron microscopy. Hollow-cone illumination imaging revealed that the density of coherent scattering regions in the as-quenched Fe{sub 85.2}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 0.8} alloy is much higher than that in the Fe{sub 76}Si{sub 9}B{sub 10}P{sub 5} bulk metallic glass. According to the C{sub s}-corrected TEM, crystalline atomic clusters, typically of ∼1 nm in diameter, are densely distributed in an amorphous matrix of Fe{sub 85.2}Si{sub 2}B{sub 8}P{sub 4}Cu{sub 0.8} alloy. Observation of four-fold and six-fold atomic arrangements of these clusters implies existence of Fe clusters with the body centered cubic structure. These Fe clusters must be responsible for the formation of ultrahigh-density α-Fe nanocrystals produced by post-annealing.

  20. Wigner crystallization in Na3Cu2O4 and Na8Cu5O10 chain compounds.

    NASA Astrophysics Data System (ADS)

    Horsch, P.; Sofin, M.; Mayr, M.; Jansen, M.

    2006-03-01

    We report the synthesis of novel doped edge-sharing chain compounds Na3Cu2O4 and Na8Cu5O10, which form insulating states with commensurate charge order [1]. We identify these systems as one-dimensional Wigner lattices, where the charge order is determined by the long-range Coulomb interaction and the number of holes in the d-shell of Cu. Our interpretation is supported by X-ray structure data as well as by an analysis of magnetic susceptibility and specific heat data. Remarkably, due to large second neighbor Cu-Cu hopping, these systems allow for an unambiguous distinction between the classical Wigner lattice and the 4kF charge-density wave of quantum mechanical origin. Finally, we briefly discuss the domain-wall type charge excitations and the theoretical expectation for the optical conductivity of 1D Wigner lattices [2]. [1] P. Horsch, M. Sofin, M. Mayr, and M. Jansen, Phys. Rev. Lett. 94, 076403 (2005). [2] M. Mayr and P. Horsch, (unpublished).

  1. Thermochemistry and dissociation dynamics of state-selected C/sub 4/H/sub 8/O/sub 2//sup +/ ions. 2. Butanoic acid

    SciTech Connect

    Butler, J.J.; Fraser-Monteiro, M.L.; Fraser-Monteiro, L.; Baer, T.; Hass, J.R.

    1982-01-01

    Photoionization efficiency curves and appearance energies for C/sub 4/H/sub 8/O/sub 2//sup +/, C/sub 3/H/sub 5/O/sub 2//sup +/, C/sub 2/H/sub 7/O/sup +/, C/sub 2/H/sub 4/O/sub 2//sup +/, C/sub 3/H/sub 7//sup +/, C/sub 3/H/sub 6//sup +/, C/sub 2/H/sub 5//sup +/, and C/sub 2/H/sub 4//sup +/ from butanoic acid have been obtained. Structures and heats of formation for some of the ions are proposed. No evidence for metastable C/sub 4/H/sub 8/O/sub 2//sup +/ ions forming C/sub 3/H/sub 5/O/sub 2//sup +/ (m/e 73) and C/sub 2/H/sub 4/O/sub 2//sup +/ (m/e 60) was found in the photoion-photoelectron coincidence (PIPECO) results. An upper limit to the parent ion lifetimes is 0.1 ..mu..s. In constrast, to the photoionization results, electron impact ionization produces strong C/sub 4/H/sub 8/O/sub 2//sup +/ metastables with lifetimes in the 10-..mu..s range. This paradox can be resolved by postulating that photoionization produces only rapidly dissociating butanoic acid ions, while a long-lived isomerized structure (or structures), such as the enol form are accessible by electron impact.

  2. Extraterrestrial Impact Episodes and Archaean to Early Proterozoic (3.8 2.4 Ga) Habitats of Life

    NASA Astrophysics Data System (ADS)

    Glikson, Andrew

    The terrestrial record is punctuated by major clustered asteroid and comet impacts, which affected the appearance, episodic extinction, radiation, and reemergence of biogenic habitats. Here I examine manifest and potential extraterrestrial impact effects on the onset and evolution of Archaean to early Proterozoic (3.8- 2.4-Ga) habitats, with reference to the Pilbara (Western Australia) and Kaapvaal (eastern Transvaal) Cratons. The range of extraterrestrial connections of microbial habitats includes cometary contribution of volatiles and amino acids, sterilization by intense asteroid and comet bombardment, supernova and solar flares, and impacttriggered volcanic and hydrothermal activity, tectonic modifications, and tsunami effects. Whereas cometary dusting of planetary atmosphere may contribute littlemodi fied extraterrestrial organic components, large impact effects result in both incineration of organic molecules and shock synthesis of new components. From projected impact incidence, ~1.3% of craters >100 km and ~3.8% of craters >250 km have to date been identified for post-3.8-Ga events, due to the mm-scale of impact spherules and the difficulty in their identification in the field - only the tip of the iceberg is observed regarding the effects of large impacts on the Precambrian biosphere, to date no direct or genetic relations between impacts and the onset or extinction of early Precambrian habitats can be confirmed. However, potential relations include (1) ~3.5-3.43 Ga - intermittent appearance of stromatolite-like structures of possible biogenic origin on felsic volcanic shoals representing intervals between mafic volcanic episodes in rapidly subsiding basins, a period during which asteroid impacts are recorded; (2) ~3.26-3.225 Ga - impact-triggered crustal transformation from mafic-ultramafic volcanic environments to rifted troughs dominated by felsic volcanics and turbidites, marked by a major magmatic peak, resulting in extensive hydrothermal activity and

  3. IL-4 is able to reverse the CD2-mediated negative apoptotic signal to CD4-CD8- alpha beta and/or gamma delta T lymphocytes.

    PubMed

    Spinozzi, F; Nicoletti, I; Agea, E; Belia, S; Moraca, R; Migliorati, G; Riccardi, C; Grignani, F; Bertotto, A

    1995-11-01

    Activation of immature thymocytes or transformed T lymphocytes via T-cell receptor (TCR)/CD3 signalling can induce programmed cell death (apoptosis). Recent data indicate that anti-CD3/TCR monoclonal antibodies (mAb) also trigger apoptosis in activated (but not resting) mature peripheral blood T lymphocytes. Here we report that triggering of resting CD4-CD8-TCR alpha beta+ and/or TCR gamma delta+ via the alternative CD2-dependent activation pathway is able to induce programmed cell death. A pair of mitogenic anti-CD2 mAb provoked a dramatic rise in [Ca2+]i that was almost entirely sustained by extracellular fluxes, and the inhibition of membrane [Ca2+/Mg2+] ATPase. The resulting endonuclease activation was able to induce DNA fragmentation, as revealed by propidium iodide staining and gel electrophoresis. Induction of apoptosis was prevented by the presence of interleukin-4 (IL-4) as well as by endonuclease inactivation with 100 microM ZnCl2, but enhanced by the contemporary block of protein kinase C. Thus it seems that in resting T lymphocytes the strong calcium signal delivered by the alternative CD2 activation pathway may act as a negative apoptotic signal in both alpha beta and gamma delta T cells with low (non-major histocompatibility complex restricted) antigenic affinity, so limiting the extension of polyclonal T-cell growth. PMID:8550074

  4. 2-{[2-Methyl-3-(2-methyl­phen­yl)-4-oxo-3,4-dihydro­quinazolin-8-yl]­oxy}acetonitrile

    PubMed Central

    El-Azab, Adel S.; Abdel-Aziz, Alaa A.-M.; Al-Omar, Mohamed A.; Ng, Seik Weng; Tiekink, Edward R. T.

    2012-01-01

    In the title compound, C18H15N3O2, the fused ring system is almost planar [the dihedral angle between the six-membered rings is 1.81 (6)°]. The 2-tolyl ring is approximately orthogonal to this plane [dihedral angle = 83.03 (7)°] as is the acetonitrile group [C—O—C—C torsion angle = 79.24 (14)°] which is also syn to the methyl substituent of the tolyl group. In the crystal, supra­molecular layers are formed in the bc plane mediated by C—H⋯O, C—H⋯N and C—H⋯π inter­actions. The tolyl group is disordered over two positions in a 0.852 (3):0.148 (3) ratio. PMID:22798783

  5. 2-Methyl-3-(2-methyl­phen­yl)-4-oxo-3,4-dihydro­quinazolin-8-yl benzoate

    PubMed Central

    El-Azab, Adel S.; Abdel-Aziz, Alaa A.-M.; Ng, Seik Weng; Tiekink, Edward R. T.

    2012-01-01

    In the title quinazolin-4-one derivative, C23H18N2O3, both the benzoate [dihedral angle = 79.99 (6)°] and the 2-tolyl [89.02 (7)°] groups are close to orthogonal to the central fused ring system. Both aryl groups are orientated towards the quinazolin-4-one-bound methyl group. In the crystal, mol­ecules are connected into a three-dimensional architecture by C—H⋯O, C—H⋯N and C—H⋯π inter­actions. PMID:22412614

  6. Anti-proliferative actions of 2-decylamino-5,8-dimethoxy-1,4-naphthoquinone in vascular smooth muscle cells

    SciTech Connect

    Lee, Jung-Jin; Zhang, Wei-Yun; Yi, Hyoseok; Kim, Yohan; Kim, In-Su; Shen, Gui-Nan; Song, Gyu-Yong; Myung, Chang-Seon

    2011-07-22

    Highlights: {yields} 2-Decylamino-DMNQ inhibited PDGF-BB-induced VSMC proliferation in a dose-dependent manner with no apparent cytotoxicity. {yields} 2-Decylamino-DMNQ inhibited PDGF-BB-induced phosphorylation of Erk1/2 and PLC{gamma}1. {yields} 2-Decylamino-DMNQ arrested a G{sub 0}/G{sub 1} cell cycle progression in association with pRb phosphorylation and PCNA expression. {yields} Both U0126, an Erk inhibitor, and U73122, a PLC{gamma} inhibitor, arrested a G{sub 0}/G{sub 1} phase of the cell cycle. -- Abstract: Naphthoquinone derivatives have been reported to possess various pharmacological activities, such as antiplatelet, anticancer, antifungal, and antiviral properties. In this study, we investigated the effects of a newly-synthesized naphthoquinone derivative, 2-decylamino-5,8-dimethoxy-1,4-naphthoquinone (2-decylamino-DMNQ), on VSMC proliferation and examined the molecular basis of the underlying mechanism. In a dose-dependent manner, 2-decylamino-DMNQ inhibited PDGF-stimulated VSMC proliferation with no apparent cytotoxic effect. While 2-decylamino-DMNQ did not affect PDGF-R{beta} or Akt, it did inhibit the phosphorylation of Erk1/2 and PLC{gamma}1 induced by PDGF. Moreover, 2-decylamino-DMNQ suppressed DNA synthesis through the arrest of cell cycle progression at the G{sub 0}/G{sub 1} phase, including the suppression of pRb phosphorylation and a decrease in PCNA expression, which was related to the downregulation of cell cycle regulatory factors, such as cyclin D1/E and CDK 2/4. It was demonstrated that both U0126, an Erk1/2 inhibitor, and U73122, a PLC{gamma} inhibitor, increased the proportion of cells in the G{sub 0}/G{sub 1} phase of the cell cycle. Thus, these results suggest that 2-decylamino DMNQ has an inhibitory effect on PDGF-induced VSMC proliferation and the mechanism of this action is through cell cycle arrest at the G{sub 0}/G{sub 1} phase. This may be a useful tool for studying interventions for vascular restenosis in coronary

  7. A Raman spectroscopic study of a hydrated molybdate mineral ferrimolybdite, Fe2(MoO4)3·7-8H2O.

    PubMed

    Sejkora, Jiří; Cejka, Jiří; Malíková, Radana; López, Andrés; Xi, Yunfei; Frost, Ray L

    2014-09-15

    Raman spectra of two well-defined ferrimolybdite samples, Fe2(3+)(Mo6+O4)3·7-8H2O, from the Krupka deposit (northern Bohemia, Czech Republic) and Hůrky near Rakovník occurrence (central Bohemia, Czech Republic) were studied and tentatively interpreted. Observed bands were assigned to the stretching and bending vibrations of molybdate anions, Fe-O units and water molecules. Number of Raman and infrared bands assigned to (MoO4)(2-) units and water molecules proved that symmetrically (structurally) nonequivalent (MoO4)(2-) and H2O are present in the crystal structure of ferrimolybdite. Approximate O-H⋯O hydrogen bond lengths (2.80-2.73 Å) were inferred from the published infrared spectra. PMID:24769361

  8. Synthesis and Thermoelectric Properties of the Clathrate-I Phase K8Li x Ge44- x/42-3 x/4

    NASA Astrophysics Data System (ADS)

    Liang, Ying; Schnelle, Walter; Veremchuk, Igor; Böhme, Bodo; Baitinger, Michael; Grin, Yuri

    2015-11-01

    Thermoelectric transport properties at temperatures below 300 K were determined for clathrate-I phases K8Li x Ge44- x/42-3 x/4 (□ denotes a vacancy) with compositions 0.25 ≤ x ≤ 2.7. Samples were prepared by solid-state reaction and compacted by spark plasma sintering. The lattice constants and chemical composition of the samples were investigated by x-ray powder diffraction and wavelength dispersive x-ray spectroscopy, respectively. Depending on composition, the temperature dependence of the electrical resistivity is metal or semiconductor-like. Absolute value of the negative Seebeck coefficient ( n-type conductivity) increased linearly with temperature. All samples had low thermal conductivity of 1-1.5 W m-1 K-1 at 300 K.

  9. Absorption and transport of deuterium-substituted 2R,4'R,8'R-alpha-tocopherol in human lipoproteins

    SciTech Connect

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

    1988-08-01

    Oral administration of a single dose of tri- or hexadeuterium substituted 2R,4'R,8'R-alpha-tocopheryl acetate (d3- or d6-alpha-T-Ac) to humans was used to follow the absorption and transport of vitamin E in plasma lipoproteins. Three hr after oral administration of d3-alpha-T-Ac (15 mg) to 2 subjects, plasma levels of d3-alpha-T were detectable; these increased up to 10 hr, reached a plateau at 24 hr, then decreased. Following administration of d6-alpha-T-Ac (15-16 mg) to 2 subjects, the percentage of deuterated tocopherol relative to the total tocopherol in chylomicrons increased more rapidly than the corresponding percentage in whole plasma. Chylomicrons and plasma lipoproteins were isolated from 2 additional subjects following administration of d3-alpha-T-Ac (140 or 60 mg). The percentage of deuterated tocopherol relative to the total tocopherol increased most rapidly in chylomicrons, then in very low density lipoproteins (VLDL), followed by essentially identical increases in low and high density lipoproteins (LDL and HDL, respectively) and lastly, in the red blood cells. This pattern of appearance of deuterated tocopherol is consistent with the concept that newly absorbed vitamin E is secreted by the intestine into chylomicrons; subsequently, chylomicron remnants are taken up by the liver from which the vitamin E is secreted in VLDL. The metabolism of VLDL in the circulation results in the simultaneous delivery of vitamin E into LDL and HDL.

  10. Final analysis of proton form factor ratio data at Q2 = 4.0, 4.8, and 5.6 GeV2

    DOE PAGESBeta

    Puckett, A. J. R.; Brash, E. J.; Gayou, O.; Jones, M. K.; Pentchev, L.; Perdrisat, C. F.; Punjabi, V.; Aniol, K. A.; Averett, T.; Benmokhtar, F.; et al

    2012-04-11

    Recently published measurements of the proton electromagnetic form factor ratio R = μp GEp/GMp at momentum transfers Q2 up to 8.5 GeV2 in Jefferson Lab Hall C deviate from the linear trend of previous measurements in Jefferson Lab Hall A, favoring a slower rate of decrease of R with Q2. While statistically compatible in the region of overlap with Hall A, the Hall C data hint at a systematic difference between the two experiments. This possibility was investigated in a reanalysis of the Hall A data. We find that the original analysis underestimated the background in the selection of elasticmore » events. The application of an additional cut to further suppress the background increases the results for R, improving the consistency between Halls A and C.« less

  11. 2-Methyl-3-(2-methyl­phen­yl)-4-oxo-3,4-dihydro­quinazolin-8-yl 4-bromo­benzene-1-sulfonate

    PubMed Central

    El-Azab, Adel S.; Abdel-Aziz, Alaa A.-M.; Ng, Seik Weng; Tiekink, Edward R. T.

    2012-01-01

    The title mol­ecule, C22H17BrN2O4S, has a twisted U shape, the dihedral angle between the quinazolin-4-one and bromo­benzene ring systems being 46.25 (8)°. In order to avoid steric clashes with adjacent substituents on the quinazolin-4-one ring, the N-bound tolyl group occupies an orthogonal position [dihedral angle = 89.59 (8)°]. In the crystal, mol­ecules are connected into a three-dimensional architecture by C—H⋯O inter­actions, with the ketone O atom accepting two such bonds and a sulfonate O atom one. PMID:22412636

  12. SU(6)⊃SU(3)⊗SU(2) and SU(8)⊃SU(4)⊗SU(2) Clebsch-Gordan coefficients

    NASA Astrophysics Data System (ADS)

    Garcia-Recio, C.; Salcedo, L. L.

    2011-04-01

    Tables of scalar factors are presented for {63}⊗ {63} and {120}⊗ {63} in SU(8)⊃SU(4)⊗SU(2), and for {35}⊗ {35} and {56}⊗ {35} in SU(6)⊃SU(3)⊗SU(2). Related tables for SU(4)⊃SU(3)⊗U(1) and SU(3)⊃SU(2)⊗U(1) are also provided so that the Clebsch-Gordan coefficients can be completely reconstructed. These are suitable to study meson-meson and baryon-meson interactions within a spin-flavor symmetric scheme.

  13. Theoretical investigation of a novel high density cage compound 4,8,11,14,15-pentanitro-2,6,9,13-tetraoxa-4,8,11,14,15-pentaazaheptacyclo[5.5.1.1(3,11).1(5,9)] pentadecane.

    PubMed

    Lin, He; Zhu, Shun-guan; Zhang, Lin; Peng, Xin-hua; Chen, Peng-yuan; Li, Hong-zhen

    2013-03-01

    A novel polynitro cage compound 4,8,11,14,15-pentanitro-2,6,9,13-tetraoxa-4,8,11,14,15-pentaazaheptacyclo [5.5.1.1(3,11).1(5,9)]pentadecane(PNTOPAHP) has been designed and investigated at the DFT-B3LYP/6-31(d) level. Properties, such as electronic structure, IR spectrum, heat of formation, thermodynamic properties and crystal structure have been predicted. This compound is most likely to crystallize in C2/c space group, and the corresponding cell parameters are Z = 8, a = 29.78 Å, b = 6.42 Å, c = 32.69 Å, α = 90.00°, β = 151.05°, γ = 90.00° and ρ = 1.94 g/cm(3). In addition, the detonation velocity and pressure have also been calculated by the empirical Kamlet-Jacobs equation. As a result, the detonation velocity and pressure of this compound are 9.82 km/s, 44.67 GPa, respectively, a little higher than those of 4,10-dinitro-2,6,8,12-tetraoxa-4,10-diazaisowurtzitane(TEX, 9.28 km/s, 40.72 GPa). This compound has a comparable chemical stability to TEX, based on the N-NO(2) trigger bond length analysis. The bond dissociation energy ranges from 153.09 kJ mol(-1) to 186.04 kJ mol(-1), which indicates that this compound meets the thermal stability requirement as an exploitable HEDM. PMID:23111684

  14. Radiation-induced amorphization of Ce-doped Mg2Y8(SiO4)6O2 silicate apatite

    NASA Astrophysics Data System (ADS)

    Zhou, Jianren; Yao, Tiankai; Lian, Jie; Shen, Yiqiang; Dong, Zhili; Lu, Fengyuan

    2016-07-01

    Ce-doped Mg2Y8(SiO4)6O2 silicate apatite (Ce = 0.05 and 0.5) were irradiated with 1 MeV Kr2+ ion beam irradiation at different temperatures and their radiation response and the cation composition dependence of the radiation-induced amorphization were studied by in situ TEM. The two Ce-doped Mg2Y8(SiO4)6O2 silicate apatites are sensitive to ion beam induced amorphization with a low critical dose (0.096 dpa) at room temperature, and exhibits significantly different radiation tolerance at elevated temperatures. Ce concentration at the apatite AI site plays a critical role in determining the radiation response of this silicate apatite, in which the Ce3+ rich Mg2Y7.5Ce0.5(SiO4)6O2 displays lower amorphization susceptibility than Mg2Y7.95Ce0.05(SiO4)6O2 with a lower Ce3+ occupancy at the AI sites. The critical temperature (Tc) and activation energy (Ea) change from 667.5 ± 33 K and 0.162 eV of Mg2Y7.5Ce0.5(SiO4)6O2 to 963.6 ± 64 K and 0.206 eV of Mg2Y7.95Ce0.05(SiO4)6O2. We demonstrate that the radiation tolerance can be controlled by varying the chemical composition, and enhanced radiation tolerance is achieved by increasing the Ce concentration at the AI site.

  15. 2-Amino-4-(4-chloro­phen­yl)-4H-chromeno[8,7-b]pyridine-3-carbonitrile

    PubMed Central

    Amr, Abd El-Galil E.; El-Agrody, Ahmed M.; Sabry, Nermien M.; Ng, Seik Weng; Tiekink, Edward R. T.

    2013-01-01

    The asymmetric unit of the title compound, C19H12ClN3O, contains two mol­ecules with similar conformations. The 14 non-H atoms comprising the 4H-chromeno[8,7-b]pyridine residue are essentially coplanar (r.m.s. deviations = 0.037 and 0.042 Å for the two mol­ecules) and the main difference between them is seen in the twist about the bond linking the main residue to the attached chloro­benzene rings [dihedral angles = 79.01 (12) and 76.22 (11)° for the two mol­ecules]. Zigzag supra­molecular chains along the a-axis direction mediated by amino–pyridine N—H⋯N hydrogen bonds feature in the crystal packing; these are connected into a three-dimensional architecture by C—H⋯π inter­actions and Cl⋯Cl contacts [Cl⋯Cl = 3.3896 (14) Å]. PMID:23634023

  16. Synthesis and molecular modelling studies of 8-arylpyrido[3',2':4,5]thieno[3,2-d]pyrimidin-4-amines as multitarget Ser/Thr kinases inhibitors.

    PubMed

    Loidreau, Yvonnick; Deau, Emmanuel; Marchand, Pascal; Nourrisson, Marie-Renée; Logé, Cédric; Coadou, Gaël; Loaëc, Nadège; Meijer, Laurent; Besson, Thierry

    2015-03-01

    This paper reports the design and synthesis of a novel series of 8-arylpyrido[3',2':4,5]thieno[3,2-d]pyrimidin-4-amines via microwave-assisted multi-step synthesis. A common precursor of the whole series, 3-amino-5-bromothieno[2,3-b]pyridine-2-carbonitrile, was rapidly synthesized in one step from commercially-available 5-bromo-2-chloronicotinonitrile. Formylation with DMF-DMA led to (E)-N'-(5-bromo-2-cyanothieno[2,3-b]pyridin-3-yl)-N,N-dimethylformimidamide (4) which was conveniently functionalized at position 8 by palladium-catalyzed Suzuki-Miyaura cross-coupling to introduce a heteroaromatic ring. High-temperature formamide-mediated cyclization of the cyanoamidine intermediate gave seventeen 8-arylpyrido[3',2':4,5]thieno[3,2-d]pyrimidin-4-amines. The inhibitory potency of the final products was evaluated against five protein kinases (CDK5/p25, CK1δ/ε, GSK3α/β, DYRK1A and CLK1) and revealed that 8-(2,4-dichlorophenyl)pyrido[3',2':4,5]thieno[3,2-d]pyrimidin-4-amine 1g specifically inhibits CK1δ/ε and CLK1 (220 and 88 nM, respectively) while its 7-(2,4-dichlorophenyl)pyrido[3',2':4,5]thieno[3,2-d]pyrimidin-4-amine isomer 10 showed no activity on the panel of tested kinases. Molecular modelling of 10 and 1g in the ATP binding sites of CK1δ/ε and CLK1 showed that functionalization at position 7 of pyrido[3',2':4,5]thieno[3,2-d]pyrimidin-4-amines is likely to induce a steric clash on the CK1δ/ε P-loop and thus a complete loss of inhibitory activity. PMID:25549552

  17. Study of magnetic properties of two samples from FeVO4-Co3V2O8 system

    NASA Astrophysics Data System (ADS)

    Guskos, N.; Zolnierkiewicz, G.; Typek, J.; Szymczak, R.; Guskos, A.; Berczynski, P.; Blonska-Tabero, A.

    2013-10-01

    Two samples containing phases formed in the FeVO4-Co3V2O8 system were prepared by a conventional sintering method. The sample designated as H5 was one-phase with the howardevansite-type structure, while the sample designated as HL7 contained a mixture of H-type and lyonsite-type structures. The temperature dependence of the electron paramagnetic resonance (EPR) spectra and static magnetic susceptibility χ was investigated in the temperature range from liquid helium to room temperature. Both the EPR spectra and the dc magnetic susceptibility showed anomalous behavior indicating that the magnetic competition process may be responsible. A comparison of the obtained results with previous studies on related compounds with the same structure, i.e. M3Fe4V6O24 (M = Mg(II), Zn(II), and Cu(II)) revealed that the observed anomaly shifted to lower temperatures on replacing the non-magnetic ions by magnetic Co(II) ions. The temperature dependence of the inverse susceptibility χ -1 indicates the existence of antiferromagnetic interactions between Fe(III) and Co(II) spins in sample H5. The obtained values of the Curie-Weiss temperatures are lower than for the Mn3Fe4V6O24 compound and comparable to compounds from M3Fe4V6O24 systems with M diamagnetic cations. The introduction of cobalt cations intensifies the magnetic frustration what is reflected in the temperature dependence of the magnetic susceptibility at low temperatures.

  18. 2-[(8-Meth­oxy­carbonyl-4b,8-dimethyl-4b,5,6,7,8,8a,9,10-octa­hydro­phenan­thren-3-yl)amino]-3,5-dinitro­benzoic acid ethyl acetate monosolvate

    PubMed Central

    Tong, Bihai; Zhang, Ye

    2012-01-01

    The title compound, C25H27N3O8·C4H8O2, has a diterpene skeleton in which the fused cyclo­hexane rings exhibit chair and half-chair conformations. An intra­molecular C—H⋯O hydrogen bond occurs. In the crystal, N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds are observed. PMID:22969568

  19. Vibration-rotation-torsion analysis of the high resolution infrared spectrum of C 2H 6 between 1330 and 1610 cm -1: The ν6, ν8, ν4 + ν12, 2 ν4 + ν9 interacting system and hot transitions from ν4 to ν4 + ν8

    NASA Astrophysics Data System (ADS)

    Lattanzi, F.; Lauro, C. di; Vander Auwera, J.

    2008-04-01

    The room temperature spectrum of ethane in the region of the ν6 and ν8 fundamentals, between 1330 and 1610 cm -1, has been re-investigated at a resolution of 0.002 cm -1. It is shown that the complex spectral structure with numerous strong local perturbations, which had hindered a global analysis of this region until now, is caused by a network of l-type resonances acting within the Fermi (or torsional-Coriolis) coupled system ν8, ν4 + ν12. The x, y-Coriolis interaction between ν6 and ν8 and vibration-rotation interactions between ν6 and 2 ν4 + ν9 also generate relevant effects on the spectrum. With an appropriate Hamiltonian model accounting for all these effects, we could fit 1814 upper state level energies belonging to ν6, ν8 and ν4 + ν12 with an overall RMS deviation better than 3.8 × 10 -3 cm -1. The determined values of the intrinsic torsional splittings in the different vibrational states are in agreement with the theoretical expectations. The intrinsic torsional splitting almost vanishes in ν8, as in digermane and disilane; it is slightly larger in ν4 + ν12 than in ν4, due to the decrease of the torsional barrier height with the excitation of ν12. For the 2 ν4 + ν9 state, the determined values of the vibrational origin and torsional splittings are in good agreement with the large increase of the torsional barrier height expected with the excitation of the ν9 mode. Several hot transitions originating from the v 4 = 1 torsional state have been observed. An analysis of 294 line positions belonging to the ( ν4 + ν8) - ν4 hot band has been performed, leading to a fit with a RMS deviation of 5.1 × 10 -3 cm -1. It is shown that a complex network of l-type resonances is also active in the ν4 + ν8,2 ν4 + ν12 system.

  20. Preparation and magnetic properties of BaFe12O19/Ni0.8Zn0.2Fe2O4 nanocomposite ferrite

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Huang, Ying; Wang, Qiufen

    2012-09-01

    Nanocomposite of hard (BaFe12O19)/soft ferrite (Ni0.8Zn0.2Fe2O4) have been prepared by the sol-gel process. The nanocomposite ferrite are formed when the calcining temperature is above 800 °C. It is found that the magnetic properties strongly depend on the presintering treatment and calcining temperature. The “bee waist” type hysteresis loops for samples disappear when the presintering temperature is 400 °C and the calcination temperature reaches 1100 °C owing to the exchange-coupling interaction. The remanence of BaFe12O19/Ni0.8Zn0.2Fe2O4 nanocomposite ferrite with the mass ratio of 5:1 is higher than a single phase ferrite. The specific saturation magnetization, remanence magnetization and coercivity are 63 emu/g, 36 emu/g and 2750 G, respectively. The exchange-coupling interaction in the BaFe12O19/Ni0.8Zn0.2Fe2O4 nanocomposite ferrite is discussed.

  1. MWCNTs decorated Mn0.8Zn0.2Fe2O4: Synthesis, characterization and compositional effect on the structural and magnetic properties

    NASA Astrophysics Data System (ADS)

    Gabal, M. A.; Al-Harthy, E. A.; Al Angari, Y. M.; Abdel Salam, M.; Zayed, Mohie A. M.

    2015-01-01

    In the present study, Mn0.8Zn0.2Fe2O4 nanoparticles, synthesized from spent Zn-C batteries extract, were successfully used for decoration of multi-walled carbon nanotubes (MWCNTs). This MWCNTs/Mn0.8Zn0.2Fe2O4 magnetic nano-composites were prepared by the addition of MWCNTs during the preparation of the entire ferrite using sucrose combustion method. The effect of MWCNTs content (0-70%) on the structural, morphological and magnetic properties of entire ferrite was investigated and discussed. The results showed that high purity Mn0.8Zn0.2Fe2O4 nano-crystallites were completely decorated on the sidewalls of the MWCNTs up to 30% content and the decoration behavior, shape and density are dependent on the composition. The saturation magnetization was observed to decrease with increasing MWCNTs content while coercivity showed a particle size dependent behavior. The composition with 70% MWCNTs was examined as adsorbent for methylene blue dye (MB) from aqueous media based on its relatively high surface area and the capability of removing the nano-composite after adsorption process using normal magnet. The nano-composite showed a very high adsorption capacity and the kinetic as well as the thermodynamics of adsorption/removal process were investigated and discussed. Repeated testing showed the applicability of the nano-composite for the removal of MB from aqueous solution frequently with acceptable efficiencies.

  2. Combinatorial topology of uranyl molybdate sheets: syntheses and crystal structures of (C 6H 14N 2) 3[(UO 2) 5(MoO 4) 8](H 2O) 4 and (C 2H 10N 2)[(UO 2)(MoO 4) 2

    NASA Astrophysics Data System (ADS)

    Krivovichev, Sergey V.; Burns, Peter C.

    2003-01-01

    Two new mixed organic-inorganic uranyl molybdates, (C 6H 14N 2) 3[(UO 2) 5(MoO 4) 8](H 2O) 4 ( 1) and (C 2H 10N 2)[(UO 2)(MoO 4) 2] ( 2), have been obtained by hydrothermal methods. The structure of 1 [triclinic, P 1¯, Z=1, a=11.8557(9), b=11.8702(9), c=12.6746(9) Å, α=96.734(2)°, β=91.107(2)°, γ=110.193(2)°, V=1659.1(2) Å] has been solved by direct methods and refined on the basis of F2 for all unique reflections to R1=0.058, which was calculated for the 5642 unique observed reflections (| Fo|⩾4 σF). The structure contains topologically novel sheets of uranyl square bipyramids, uranyl pentagonal bipyramids, and MoO 4 tetrahedra, with composition [(UO 2) 5(MoO 4) 8] 6-, that are parallel to (-101). H 2O groups and 1,4-diazabicyclo [2.2.2]-octane (DABCO) molecules are located in the interlayer, where they provide linkage of the sheets. The structure of 2 [triclinic, P 1¯, Z=2, a=8.4004(4), b=11.2600(5), c=13.1239(6) Å, α=86.112(1)°, β=86.434(1)°, γ=76.544(1)°, V=1203.14(10) Å] has been solved by direct methods and refined on the basis of F2 for all unique reflections to R1=0.043, which was calculated for 5491 unique observed reflections (| Fo|⩾4 σF). The structure contains topologically novel sheets of uranyl pentagonal bipyramids and MoO 4 tetrahedra, with composition [(UO 2)(MoO 4) 2] 2-, that are parallel to (110). Ethylenediamine molecules are located in the interlayer, where they provide linkage of the sheets. All known topologies of uranyl molybdate sheets of corner-sharing U and Mo polyhedra can be described by their nodal representations (representations as graphs in which U and Mo polyhedra are given as black and white vertices, respectively). Each topology can be derived from a simple black-and-white graph of six-connected black vertices and three-connected white vertices by deleting some of its segments and white vertices.

  3. The dimensionality of ammonium reorientation in (NH4)2S2O8: the view from neutron spectroscopy

    NASA Astrophysics Data System (ADS)

    Prager, M.; Grimm, H.; Natkaniec, I.; Nowak, D.; Unruh, T.

    2008-03-01

    The dynamics of the ammonium ion in ammonium persulfate is studied by inelastic neutron scattering at energy transfers between 0.7 µeV and about 100 meV. NH4+ librational modes are clearly split into four energetically different bands, in agreement with the absence of symmetry at the ammonium site. One strong, one medium and two weak hydrogen bonds from the NH4 ion to neighboring oxygens lead to this unusual potential shape with one dominating overlap matrix elements hi. Therefore the ammonium dynamics seen by neutron tunneling spectroscopy looks like a rotation about a single axis, that of the strongest hydrogen bond. Quasi-elastic scattering up to T = 100 K is dominated by jumps about this specific axis, too. Jumps about the second weak axis modify the quasi-elastic scattering at higher temperature. Results of a previous nuclear magnetic resonance (NMR) quadrupole resonance experiment are consistently interpreted to show the dynamics around the remaining two strong axes. The reduced isotope effect of the lowest librational band is due to a special shape of the potential and not to changes of the hydrogen bond with deuteration.

  4. Irreversibility line and flux pinning properties in a multilayered cuprate superconductor of Ba2Ca3Cu4O8(O,F)2 (Tc = 105 K)

    NASA Astrophysics Data System (ADS)

    Shirage, P. M.; Iyo, A.; Shivagan, D. D.; Tanaka, Y.; Kito, H.; Kodama, Y.

    2008-07-01

    Irreversibility line (IL) and flux pinning properties were investigated for a Ba2Ca3Cu4O8(O,F)2 (F-0234) multilayered cuprate superconductor with a Tc of 105 K. The intragrain critical current density (Jc) and irreversibility field (Birr) were determined by using Bean's critical state model for the grain-aligned sample (nominal composition Ba2Ca3Cu4O8.7F1.3). The irreversibility line (IL) of F-0234 is much lower than that of (Cu,C)Ba2Ca3Cu4Oy ((Cu, C)-1234) and HgBa2Ca3Cu4Oy (Hg-1234) in spite of the spacing between the superconducting blocks of F-0234 (7.3 Å) being much thinner. The double logarithmic plot of Birr field versus [1-(T/Tc) ] analysis hints that the flux line melting model has been adopted. An anisotropy factor of 65 was calculated from a 3D to 2D crossover field of about 0.95 T. Due to the high anisotropy of this system, a low IL has resulted. The flux pinning force density Fp ( ≈JcB) exhibits scaling behaviour when the magnetic field B is normalized by the Birr field. Analysis of the normalized pinning force reveals that a surface pinning mechanism is dominant and the reduced magnetic field bmax = 0.2 agrees with surface pinning mechanism with closely spaced pins.

  5. 4-Hydroxybenzyl modification of the highly teratogenic retinoid, 4-[(1E)-2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthalenyl)-1-propen-1-yl]benzoic acid (TTNPB), yields a compound that induces apoptosis in breast cancer cells and shows reduced teratogenicity.

    PubMed

    Anding, Allyson L; Nieves, Nirca J; Abzianidze, Victoria V; Collins, Michael D; Curley, Robert W; Clagett-Dame, Margaret

    2011-11-21

    Retinoids are a class of compounds with structural similarity to vitamin A. These compounds inhibit the proliferation of many cancer cell lines but have had limited medical application as they are often toxic at therapeutic levels. Efforts to synthesize retinoids with a greater therapeutic index have met with limited success. 4-[(1E)-2-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-2-naphthalenyl)-1-propen-1-yl]benzoic acid (TTNPB) is one of the most biologically active all-trans-retinoic acid (atRA) analogues and is highly teratogenic. In this study, we show that modification of the TTNPB carboxyl group with an N-(4-hydroxyphenyl)amido (4HPTTNPB) or a 4-hydroxybenzyl (4HBTTNPB) group changes the activity of the compound in cell culture and in vivo. Unlike TTNPB, both compounds induce apoptosis in cancer cells and bind poorly to the retinoic acid receptors (RARs). Like the similarly modified all-trans-retinoic acid (atRA) analogues N-(4-hydroxyphenyl)retinamide (4-HPR/fenretinide) and 4-hydroxybenzylretinone (4-HBR), 4HBTTNPB is a potent activator of components of the ER stress pathway. The amide-linked analogue, 4HPTTNPB, is less toxic to developing embryos than the parent TTNPB, and most significantly, the 4-hydroxybenzyl-modified compound (4HBTTNPB) that cannot be hydrolyzed in vivo to the parent TTNPB compound is nearly devoid of teratogenic liability. PMID:21939267

  6. Environmental management technology demonstration and commercialization: Tasks 2, 3, 4, and 8. Semiannual report, October 1994--March 1995

    SciTech Connect

    Hawthorne, S.B.; Ness, R.O. Jr.; Nowok, J.W.; Pflughoeft-Hassett, D.; Hurley, J.P.; Steadman, E.N.

    1995-05-01

    The objective of the Environmental Management program at the Energy and Environmental Research Center (EERC) is to develop, demonstrate, and commercialize technologies that address the environmental management needs of contaminated sites, including characterization, sensors, and monitoring; low-level mixed waste processing; material disposition technology; improved waste forms; in situ containment and remediation; and efficient separation technologies for radioactive wastes. Task 2 is the extraction and analysis of pollutant organics from contaminated solids using off-line supercritical fluid extraction (SFE) and on-line SFE-infrared spectroscopy. Task 3, pyrolysis of plastics, has as its objectives to develop a commercial process to significantly reduce the volume of mixed-plastics-paper-resin waste contaminated with low-level radioactive material; concentrate contaminants in a collectible form; and determine the distribution and form of contaminants after pyrolysis of the mixed waste. Task 4, stabilization of vitrified wastes, has as its objectives to (1) demonstrate a waste vitrification procedure for enhanced stabilization of waste materials and (2) develop a testing protocol to understand the long-term leaching behavior of the stabilized waste form. The primary objective of Task 8, Management and reporting, is coordination of this project with other programs and opportunities. In addition, management oversight will be maintained to ensure that tasks are completed and coordinated as planned and that deliverables are submitted in a timely manner. Accomplishments to date is each task are described. 62 refs.

  7. La0.6Sr0.4Co0.2Fe0.8O3 cathodes incorporated with Sm0.2Ce0.8O2 by three different methods for solid oxide fuel cells

    NASA Astrophysics Data System (ADS)

    Shen, Fengyu; Lu, Kathy

    2015-11-01

    The incorporation of Sm0.2Ce0.8O2 (SDC) into La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) is carried out by three methods: mechanical mixing, infiltration, and dip coating. The effects of SDC on the electrochemical performance of the LSCF cathodes are studied by electrochemical impedance spectroscopy (EIS) at 800 °C for 100 h. LSCF mechanically mixed with SDC as the cathode decreases the electrochemical performance of the half-cell; the LSCF cathode infiltrated with SDC offers faster activation and decreased resistance with thermal treatment time; and the LSCF cathode dip coated with SDC has the smallest polarization resistance. These cathodes also show clear microstructure differences at the cathode/interconnect interface after 100 h of thermal treatment. SrCrO4 phase forms on all the cathodes near the interconnect. Reactions between the mechanically mixed cathode and the YSZ electrolyte destroy the electrolyte. The influence of SDC catalyst on oxygen adsorption, dissociation, and incorporation is explained for each type of cathodes. Overall, dip coating method is recommended for incorporation of SDC into the LSCF cathode.

  8. Chemically induced magnetism and magnetoresistance in La(0.8)Sr(1.2)Mn(0.6)Rh(0.4)O(4).

    PubMed

    Battle, P D; Bell, A M; Blundell, S J; Coldea, A I; Cussen, E J; Hardy, G C; Marshall, I M; Rosseinsky, M J; Steer, C A

    2001-08-01

    It is shown by magnetometry and microSR spectroscopy that short-range magnetic interactions between the Mn cations in the nonmetallic K(2)NiF(4)-like phase La(0.8)Sr(1.2)Mn(0.6)Rh(0.4)O(4) become significant below approximately 200 K. Negative magnetoresistance (rho/rho(0) approximately 0.5 in 14 T at 108 K) is apparent below this temperature. Neutron diffraction has shown that an applied magnetic field of 5 T is sufficient to induce saturated (3.38(7)mu(B) per Mn) long-range ferromagnetic ordering of the atomic moments at 2 K, and that the induced ordering persists up to a temperature of 50 K in 5 T. Spin glass behavior is observed below 20 K in the absence of an applied field. The induced magnetic ordering is attributed to the subtle changes in band structure brought about by the external field, and to the controlling influence of Rh(3+) over the relative strength of competing magnetic exchange interactions. PMID:11480982

  9. Oxide Melt Solution Calorimetry of Fe2+ -bearing Oxides and Application to the Magnetite - Maghemite (Fe3O4-Fe8/3O4) system

    SciTech Connect

    Lilova, Kristina I.; Xu, Fen; Rosso, Kevin M.; Pearce, Carolyn I.; Kamali, Saeed; Navrotsky, Alexandra

    2012-01-01

    A consistent methodology for obtaining enthalpy of formation of Fe{sup 2+}-containing binary and multicomponent oxides using high temperature oxide melt solution calorimetry has been developed. The enthalpies of wuestite (FeO) and magnetite (Fe{sub 3}O{sub 4}) oxidation to hematite (Fe{sub 2}O{sub 3}) were measured using oxidative drop solution calorimetry in which the final product is dissolved ferric oxide. Two methods were applied: drop solution calorimetry at 1073 K in lead borate solvent and at 973 K in sodium molybdate, each under both oxygen flowing over and bubbling through the solvent, giving consistent results in agreement with literature values. The enthalpies of formation of all three iron oxides from the elements were obtained using a thermodynamic cycle involving the directly measured oxidative dissolution enthalpy of iron metal in sodium molybdate at 973 K and gave excellent consistency with literature data. The methodology was then applied to the magnetite - maghemite system. The enthalpy of mixing of the Fe{sub 3}O{sub 4}-Fe{sub 8/3}O{sub 4} spinel solid solution is exothermic and, 2 represented by a subregular (Margules) formalism, {Delta}H{sub mix} = x(1-x)(-63.36 {+-} 8.60(1-x) + 17.65 {+-} 6.40x) kJ/mol, where x is the mole fraction of magnetite. The entropies of mixing of the solid solution were calculated for different assumptions about the distribution of cations, charges, and vacancies in these defect spinels. The different models lead to only small differences in the entropy of mixing. Calculated free energies of mixing show no evidence for a solvus in the magnetite - maghemite system.

  10. Unexpected ring-closure products derived from 3-(2-allylanilino)-3-phenylacrylate esters: crystal and molecular structures of 3-acetyl-8-allyl-6-methyl-2-phenylquinolin-4-yl acetate and (2RS)-2,8-dimethyl-4-phenyl-1,2-dihydro-6H-pyrrolo[3,2,1-ij]quinolin-6-one.

    PubMed

    Luque, Adriana L; Sanabria, Carlos M; Palma, Alirio; Cobo, Justo; Glidewell, Christopher

    2016-08-01

    The reactions of two 3-(2-allylanilino)-3-phenylacrylate esters with acetic anhydride and with strong acids has revealed a richly diverse reactivity providing a number of unexpected products. Thus, acetylation of ethyl 3-(2-allylanilino)-3-phenylacrylate, (Ia), or ethyl 3-(2-allyl-4-methylanilino)-3-phenylacrylate, (Ib), with acetic anhydride yields not only the expected acetylated esters, (II), as the major products but also the unexpected polysubstituted quinolines 3-acetyl-8-allyl-2-phenylquinolin-4-yl acetate, (IIIa), and 3-acetyl-8-allyl-6-methyl-2-phenylquinolin-4-yl acetate, (IIIb), as minor products. Subsequent reaction of the major product ethyl 2-[(2-allyl-4-methylanilino)(phenyl)methylidene]-3-oxobutanoate, (IIb), with concentrated sulfuric acid did not provide the expected 3-acetylquinoline derivative, but instead two unexpected products, namely ethyl 4-ethyl-2-phenyl-1,4-dihydroquinoline-3-carboxylate, (IV), and ethyl 3-acetyl-4-ethyl-2-phenyl-3,4-dihydroquinoline-3-carboxylate, (V), in yields of 39 and 22%, respectively. The reaction of (Ib) with Eaton's reagent gave both the quinoline (Z)-6-methyl-2-phenyl-8-(prop-1-en-1-yl)quinolin-4(1H)-one, (VI), and the unexpected tricyclic product (2RS)-2,8-dimethyl-4-phenyl-1,2-dihydro-6H-pyrrolo[3,2,1-ij]quinolin-6-one, (VII), in yields of 71 and 12%, respectively. The products (II)-(VII) have all been fully characterized spectroscopically and the crystal structures of two of the unexpected products, i.e. (IIIb) (C23H21NO3) and (VII) (C19H17NO), are reported here. The formation of compounds (IV), (V) and (VII) all require an isomerization of the initial allyl substituent, with migration of the C=C double bond from the terminal site to the internal site. In (IIIb), the two acetyl substituents are oriented such that the intramolecular distance between the two carbonyl O atoms is only 3.243 (2) Å, and in (VII), the five-membered ring adopts a twisted half-chair conformation. The molecules of compound (IIIb

  11. Completing the Cycle: It's Up to You. Phase 2, An Integrated Unit in Environmental Education, Grades 4-8.

    ERIC Educational Resources Information Center

    Indiana State Dept. of Education, Indianapolis. Center for School Improvement and Performance.

    This curriculum module is designed to provide teachers with classroom activities that promote an understanding of environmental issues such as conservation, preservation, ecology, resource management, solid waste management, and recycling. The activities enable teachers, students in grades 4 through 8, and families to begin thinking about these…

  12. Discovery of a series of 8-(2,3-dihydro-1,4-benzoxazin-4-ylmethyl)-2-morpholino-4-oxo-chromene-6-carboxamides as PI3Kβ/δ inhibitors for the treatment of PTEN-deficient tumours.

    PubMed

    Barlaam, Bernard; Cosulich, Sabina; Degorce, Sébastien; Fitzek, Martina; Green, Stephen; Hancox, Urs; Lambert-van der Brempt, Christine; Lohmann, Jean-Jacques; Maudet, Mickaël; Morgentin, Rémy; Péru, Aurélien; Plé, Patrick; Saleh, Twana; Ward, Lara; Warin, Nicolas

    2016-05-01

    We report the discovery and optimisation of a series of 8-(2,3-dihydro-1,4-benzoxazin-4-ylmethyl)-2-morpholino-4-oxo-chromene-6-carboxamides, leading to compound 16 as a potent and selective PI3Kβ/δ inhibitor: PI3Kβ cell IC50 0.012μM (in PTEN null MDA-MB-468 cell) and PI3Kδ cell IC50 0.047μM (in Jeko-1 B-cell), with good pharmacokinetics and physical properties. In vivo, 16 showed profound pharmacodynamic modulation of AKT phosphorylation in a mouse PTEN-deficient PC3 prostate tumour xenograft after a single oral dose and gave excellent tumour growth inhibition in the same model after chronic oral dosing. Compound 16 was selected as a preclinical candidate for the treatment of PTEN-deficient tumours. PMID:26996374

  13. Effects of annealing temperature on structure and magnetic properties of CoAl0.2Fe1.8O4/SiO2 nanocomposites

    NASA Astrophysics Data System (ADS)

    Wang, L.; Li, J.; Liu, M.; Zhang, Y. M.; Lu, J. B.; Li, H. B.

    2012-12-01

    CoAl0.2Fe1.8O4/SiO2 nanocomposites were prepared by sol-gel method. The effects of annealing temperature on the structure and magnetic properties of the samples were studied by X-ray diffraction, transmission electron microscopy, vibrating sample magnetometer and Mössbauer spectroscopy. The results show that the CoAl0.2Fe1.8O4 in the samples exhibits a spinel structure after being annealed. As annealing temperature increases from 800 to 1200 °C, the average grain size of CoAl0.2Fe1.8O4 in the nanocomposites increases from 5 to 41 nm while the lattice constant decreases from 0.8397 to 0.8391 nm, the saturation magnetization increases from 21.96 to 41.53 emu/g. Coercivity reaches a maximum of 1082 Oe for the sample annealed at 1100 °C, and thereafter decreases with further increasing annealing temperature. Mössbauer spectra show that the isomer shift decreases, hyperfine field increases and the samples transfer from mixed state of superparamagnetic and magnetic order to the completely magnetic order with annealing temperature increasing from 800 to 1200 °C.

  14. Atomic layer etching of SiO2 under Ar/ C4F8 plasmas with pulsed bias

    NASA Astrophysics Data System (ADS)

    Zhang, Sai-Qian; Dai, Zhong-Ling; Wang, You-Nian; Plasma Simulation; Experiment Group (PSEG) Team

    2015-09-01

    The purge steps in the atomic layer etching (ALE) reduce the throughput and increase the costs. By elaborately choosing bias pulse waveforms, ALE can be achieved without alternating feedstock gas, although compromises are needed between throughput and precision. In this study, a multi-scale model is used to simulate ALE of SiO2 with a pulsed bias in Ar/C4F8 plasmas. Firstly, a commercial software CFD-ACE + is used to calculate the reactant fluxes towards the substrate in a CCP reactor. The ion bombardment energy and angular distributions at substrate are calculated with a hybrid sheath model, where electric field is got from fluid equations, and the ion-neutral collisions are considered applying the Monte Carlo(MC) method. Then, the reactant transport and surface MC reaction algorithm are coupled in a feature scale model. Influences of bias pulse frequency and duty ratio on atomic precision control are studied. Also, comparisons are made between conventional ALE and pulsed bias etching. Results show that when pulsed bias is used instead of alternating the feedstock gas, we can still achieve certain self-limiting nature in etching, with higher throughput and acceptable loss of precision. Supported by National Natural Science Foundation of China (No. 11375040).

  15. Solid-phase synthesis of 2-substituted 4-amino-7-oxo-5,6,7,8-tetrahydropyrido[2,3-d]pyrimidines.

    PubMed

    Falcó, José L; Borrell, José I; Teixidó, Jordi

    2003-01-01

    An efficient solid-phase synthesis of 2-substituted 4-aminopyrido[2,3-d]pyrimidines 15 is reported. The procedure started by solid supporting a p-hydroxybenzaldehyde 8 to the Wang resin by using the Mitsunobu protocol. The resulting aldehyde 17 was treated with a substituted acid methyl malonate 10 to afford the corresponding alpha, beta-unsaturated ester 18, which was converted to the Michael adduct 21 by reaction with malononitrile. Cyclization of 21 with an amidine system 13 yielded the solid supported pyridopyrimidine 22, which afforded the corresponding 2-substituted 4-aminopyrido[2,3-d]pyrimidine 15 upon treatment with TFA:DCM. Compounds 15 present three diversity centers R1, R2 and R3. Having validated the chemistry on solid support, a 32-membered combinatorial library was obtained using this protocol. PMID:14761159

  16. 7 CFR 8.4 - Basic premises.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Basic premises. 8.4 Section 8.4 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.4 Basic premises. (a) The 4-H Club Name and Emblem are held in trust by the Secretary of Agriculture of the United States Department of...

  17. Crystal structure and luminescence properties of Bi3+activated Ca2Y8(SiO4)6O2 phosphors under near UV excitation

    NASA Astrophysics Data System (ADS)

    Sun, Zhihua; Wang, Minqiang; Yang, Zhi; Liu, Kaiping; Zhu, Feiyan

    2016-07-01

    Oxyapatite Ca2Y8-x(SiO4)6O2:xBi3+phosphor has been prepared via high temperature solid-state reaction. Its crystal structure and PL properties were investigated by X-ray diffraction, photoluminescence excitation and emission spectra. The results indicated that the Ca2Y8(SiO4)6O2 crystallizes as a hexagonal structure with a space group of P63/m and lattice constants of a=b=9.3507 Å, c=6.7899 Å, α=β=90.00°, γ=120.00°, V=514.14 Å3; The phosphor has two prominent emission bands: when excited under 320-360 nm, the phosphors emit a broad band centered at 495 nm due to the 3P1-1S0 transition of Bi3+ in 4f (C3) sites; when excited under 380 nm, the phosphors emit a broad band centered at 411 nm due to the 3P1-1S0 transition of Bi3+ in 6h (Cs) sites. The emission color varies from the greenish blue to blue as the excitation wavelength increases from 335 to 380 nm. The optimal intensity of emission band was observed when x=0.015 in the Ca2Y8-x(SiO4)6O2:xBi3+ series. The average critical distance Rc among Bi3+ ions is determined to be 20.15 Å.

  18. Cluster Chemistry in Electron-Poor Ae-Pt-Cd Systems (Ae=Ca, Sr, Ba): (Sr,Ba)Pt2Cd4, Ca6Pt8Cd16, and Its Known Antitype Er6Pd16Sb8

    SciTech Connect

    Samal, Saroj L.; Gulo, Fakhili; Corbett, John D.

    2013-02-18

    Three new ternary polar intermetallic compounds, cubic Ca6Pt8Cd16, and tetragonal (Sr, Ba)Pt2Cd4 have been discovered during explorations of the Ae–Pt–Cd systems. Cubic Ca6Pt8Cd16 (Fm-3m, Z = 4, a = 13.513(1) Å) contains a 3D array of separate Cd8 tetrahedral stars (TS) that are both face capped along the axes and diagonally bridged by Pt atoms to generate the 3D anionic network Cd8[Pt(1)]6/2[Pt(2)]4/8. The complementary cationic surface of the cell consists of a face-centered cube of Pt(3)@Ca6 octahedra. This structure is an ordered ternary variant of Sc11Ir4 (Sc6Ir8Sc16), a stuffed version of the close relative Na6Au7Cd16, and a network inverse of the recent Er6Sb8Pd16 (compare Ca6Pt8Cd16). The three groups of elements each occur in only one structural version. The new AePt2Cd4, Ae = Sr, Ba, are tetragonal (P42/mnm,Z = 2, a ≈ 8.30 Å, c ≈ 4.47 Å) and contain chains of edge-sharing Cd4 tetrahedra along c that are bridged by four-bonded Ba/Sr. LMTO-ASA and ICOHP calculation results and comparisons show that the major bonding (Hamilton) populations in Ca6Pt8Cd16 and Er6Sb8Pd16 come from polar Pt–Cd and Pd–Sb interactions, that Pt exhibits larger relativistic contributions than Pd, that characteristic size and orbital differences are most evident for Sb 5s, Pt8, and Pd16, and that some terms remain incomparable, Ca–Cd versus Er–Pd.

  19. [Effect of Cynaropicrin on 2,3,4,7,8-Pentachlorodibenzofuran-induced Wasting Syndrome and Oxidative Stress].

    PubMed

    Yamada, Ken-ichi; Ishii, Yuji; Takeda, Tomoki; Kuroki, Hiroaki; Mitoma, Chikage; Uchi, Hiroshi; Furue, Masutaka; Yamada, Hideyuki

    2015-05-01

    The effect of cynaropicrin that is the major component of an edible plant, artichoke (Cynara scolymus) on 2,3,4,7,8-pentachlorodibenzofuran (PenCDF)-induced toxicity in mice was studied. We evaluated the effect of cynaropicrin on the wasting syndrome and oxidative stress elicited by PenCDF. However, the PenCDF dose-response relationship on the wasting syndrome has been superficial. Therefore, we determined the dose which causes wasting syndrome in C57BL/6J mice, a responsive strain to dioxins. Since 2,3,7,8-tetrachlorodibenzo-p-dioxin (0.1 mg/kg, p.o.) induces hepatic ethoxyresorfin O-deethylase (EROD) activity in mice, we set the doses of PenCDF at 0.3, 1.0, 3.0, 5.0 and 10 mg/kg (once, p.o.) on the basis of its toxic-eqivalency factor (0.3). The wasting syndrome was evaluated by measuring the daily changes of body weight. Thiobarbituric acid-reactive substances were used as an index of oxidative stress. Of PenCDF doses examined, wasting syndrome and oxidative stress took place most markedly in 5 mg/kg. In disagreement with this, EROD activity which is the marker of the aryl hydrocarbon receptor-dependent induction of cytochrome P450 1a1 was elevated most abundantly at 0.3 mg/kg. Then, we examined the effect of cynaropicrin on the wasting syndrome and oxidative stress provoked by PenCDF at 5 mg/kg. However, this compound up to 20 mg/kg (p.o.) did not attenuate PenCDF-induced wasting syndrome. On the contray, PenCDF-induced oxidateive stress was suppressed by cynaropicrin at the highest dose (20 mg/kg), although EROD activity was increased rather than reduced by cynaropicrin at lower doses. Thus, it is suggested that cynaropicrin has an ability to reduce oxidative stress caused by PenCDF. PMID:26226680

  20. 40 CFR 721.10030 - Pyrimido[5,4-g]pteridine-2,4,6,8-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., 4-methylbenzenesulfonate, base-hydrolyzed. 721.10030 Section 721.10030 Protection of Environment...-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed. (a) Chemical substance and significant new uses...-methylbenzenesulfonate, base-hydrolyzed (PMN P-01-919; CAS No. 346709-25-9) is subject to reporting under this...

  1. 40 CFR 721.10030 - Pyrimido[5,4-g]pteridine-2,4,6,8-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., 4-methylbenzenesulfonate, base-hydrolyzed. 721.10030 Section 721.10030 Protection of Environment...-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed. (a) Chemical substance and significant new uses...-methylbenzenesulfonate, base-hydrolyzed (PMN P-01-919; CAS No. 346709-25-9) is subject to reporting under this...

  2. 40 CFR 721.10030 - Pyrimido[5,4-g]pteridine-2,4,6,8-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., 4-methylbenzenesulfonate, base-hydrolyzed. 721.10030 Section 721.10030 Protection of Environment...-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed. (a) Chemical substance and significant new uses...-methylbenzenesulfonate, base-hydrolyzed (PMN P-01-919; CAS No. 346709-25-9) is subject to reporting under this...

  3. 40 CFR 721.10030 - Pyrimido[5,4-g]pteridine-2,4,6,8-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., 4-methylbenzenesulfonate, base-hydrolyzed. 721.10030 Section 721.10030 Protection of Environment...-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed. (a) Chemical substance and significant new uses...-methylbenzenesulfonate, base-hydrolyzed (PMN P-01-919; CAS No. 346709-25-9) is subject to reporting under this...

  4. 40 CFR 721.10030 - Pyrimido[5,4-g]pteridine-2,4,6,8-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., 4-methylbenzenesulfonate, base-hydrolyzed. 721.10030 Section 721.10030 Protection of Environment...-tetramine, 4-methylbenzenesulfonate, base-hydrolyzed. (a) Chemical substance and significant new uses...-methylbenzenesulfonate, base-hydrolyzed (PMN P-01-919; CAS No. 346709-25-9) is subject to reporting under this...

  5. Site characterization plan: Yucca Mountain Site, Nevada Research and Development Area, Nevada: Volume 6, Part B: Chapter 8, Sections 8.3.2 through 8.3.4.4

    SciTech Connect

    1988-12-01

    This site characterization plan (SCP) has been developed for the candidate repository site at Yucca Mountain in the State of Nevada. The SCP includes a description of the Yucca Mountain site (Chapters 1-5), a conceptual design for the repository (Chapter 6), a description of the packaging to be used for the waste to be emplaced in the repository (Chapter 7), and a description of the planned site characterization activities (Chapter 8). The schedules and milestones presented in Sections 8.3 and 8.5 of the SCP were developed to be consistent with the June 1988 draft Amendment to the DOE`s Mission Plan for the Civilian Radioactive Waste Management Program. The five month delay in the scheduled start of exploratory shaft construction that was announced recently is not reflected in these schedules. 35 figs., 70 tabs.

  6. Synthesis, bioactivity and structure-activity relationships of new 2-aryl-8-OR-3,4-dihydroisoquinolin-2-iums salts as potential antifungal agents.

    PubMed

    Zhu, Li-Fei; Hou, Zhe; Zhou, Kun; Tong, Zong-Bo; Kuang, Qian; Geng, Hui-Ling; Zhou, Le

    2016-05-15

    As our continuing research on antifungal dihydroisoquinolin-2-ium salts, forty 2-aryl-8-OR-3,4-dihydroisoquinolin-2-ium bromides were synthesized and characterized by spectroscopic analysis. By using the mycelium growth rate method, the compounds were evaluated for antifungal activity against three plant pathogenic fungi and structure-activity relationships (SAR) were derived. The vast majority of the compounds displayed the medium to high activity with inhibition rates of 50-100% at 150μM. About half of the compounds were more active than their natural model compounds sanguinarine and chelerythrine for all the fungi, and part or most of them were more active than positive drugs thiabendazole and azoxystrobin. SAR analysis showed that both substitution patterns of the C-ring and the type of 8-OR group significantly influenced the activity. Thus, a series of new title compounds with excellent antifungal potency emerged. PMID:27072907

  7. 11 CFR 8.4 - Contents.

    Code of Federal Regulations, 2010 CFR

    2003-02-03

    ... voter identification number, the state's Privacy Act notice required at 11 CFR 8.6(c) shall be reprinted... 11 Federal Elections 1 2003-02-03 2003-02-03 false Contents. 8.4 Section 8.4 Federal Elections... Voter Registration Form § 8.4 Contents. (a) Information about the applicant. The application...

  8. 11 CFR 8.4 - Contents.

    Code of Federal Regulations, 2010 CFR

    2001-01-01

    ... voter identification number, the state's Privacy Act notice required at 11 CFR 8.6(c) shall be reprinted... 11 Federal Elections 1 2001-01-01 2001-01-01 false Contents. 8.4 Section 8.4 Federal Elections... Voter Registration Form § 8.4 Contents. (a) Information about the applicant. The application...

  9. 11 CFR 8.4 - Contents.

    Code of Federal Regulations, 2012 CFR

    2009-01-01

    ... voter identification number, the state's Privacy Act notice required at 11 CFR 8.6(c) shall be reprinted... 11 Federal Elections 1 2009-01-01 2009-01-01 false Contents. 8.4 Section 8.4 Federal Elections... Voter Registration Form § 8.4 Contents. (a) Information about the applicant. The application...

  10. 11 CFR 8.4 - Contents.

    Code of Federal Regulations, 2014 CFR

    2008-01-01

    ... voter identification number, the state's Privacy Act notice required at 11 CFR 8.6(c) shall be reprinted... 11 Federal Elections 1 2008-01-01 2008-01-01 false Contents. 8.4 Section 8.4 Federal Elections... Voter Registration Form § 8.4 Contents. (a) Information about the applicant. The application...

  11. Gold(I)-catalyzed cycloisomerization of alkynyl hydroxyallyl tosylamides to 4-oxa-6-azatricyclo[3.3.0.0(2,8)]octanes.

    PubMed

    Park, Yujung; Kim, Sun Young; Park, Ji Hoon; Cho, Jieun; Kang, Youn Kyung; Chung, Young Keun

    2011-05-14

    Reaction of alkyne allyl alcohols tethered with N-(p-tolylsulfonamide) in the presence of a cationic gold(I) catalyst gave new cycloisomerization products, 4-oxa-6-azatricyclo[3.3.0.0(2,8)]octanes. PMID:21448474

  12. Crystal structure of a Pd4 carbonyl tri-phenyl-phosphane cluster [Pd4(CO)5(PPh3)42C4H8O, comparing solvates.

    PubMed

    Robeyns, Koen; Willocq, Christopher; Tinant, Bernard; Devillers, Michel; Hermans, Sophie

    2016-02-01

    Attempts to synthesize Au-Pd heterometallic compounds from homonuclear palladium or gold complexes, [Pd(PtBu2)2] and [Au(PPh3)Cl] in a tetra-hydro-furan (THF) solution under a CO atmosphere resulted in a homonuclear Pd cluster, namely penta-kis-(μ-carbonyl-κ(2) C:C)tetra-kis-(tri-phenyl-phosphane-κP)tetrapalladium(5 Pd-Pd) tetra-hydro-furan disolvate, [Pd4(CO)5(C18H15P)42C4H8O. The complex mol-ecule lies on a twofold rotation axis. The crystal structure is described in relation to the CH2Cl2 solvate previously determined by our group [Willocq et al. (2011 ▸). Inorg. Chim. Acta, 373, 233-242], and in particular to the desolvated structure [Feltham et al. (1985 ▸). Inorg. Chem. 24, 1503-1510]. It is assumed that the title compound transforms into the latter structure, upon gradual loss of solvent mol-ecules. In the title compound, the symmetry-unique THF solvent mol-ecule is linked to the complex mol-ecule by a weak C-H⋯O hydrogen bond. Contributions of disordered solvent molecules to the diffraction intensities, most likely associated with methanol, were removed with the SQUEEZE [Spek (2015). Acta Cryst. C71, 9-18] algorithm. PMID:26958368

  13. Crystal structure of a Pd4 carbonyl tri­phenyl­phosphane cluster [Pd4(CO)5(PPh3)42C4H8O, comparing solvates

    PubMed Central

    Robeyns, Koen; Willocq, Christopher; Tinant, Bernard; Devillers, Michel; Hermans, Sophie

    2016-01-01

    Attempts to synthesize Au–Pd heterometallic compounds from homonuclear palladium or gold complexes, [Pd(PtBu2)2] and [Au(PPh3)Cl] in a tetra­hydro­furan (THF) solution under a CO atmosphere resulted in a homonuclear Pd cluster, namely penta­kis­(μ-carbonyl-κ2 C:C)tetra­kis­(tri­phenyl­phosphane-κP)tetrapalladium(5 Pd—Pd) tetra­hydro­furan disolvate, [Pd4(CO)5(C18H15P)42C4H8O. The complex mol­ecule lies on a twofold rotation axis. The crystal structure is described in relation to the CH2Cl2 solvate previously determined by our group [Willocq et al. (2011 ▸). Inorg. Chim. Acta, 373, 233–242], and in particular to the desolvated structure [Feltham et al. (1985 ▸). Inorg. Chem. 24, 1503–1510]. It is assumed that the title compound transforms into the latter structure, upon gradual loss of solvent mol­ecules. In the title compound, the symmetry-unique THF solvent mol­ecule is linked to the complex mol­ecule by a weak C—H⋯O hydrogen bond. Contributions of disordered solvent molecules to the diffraction intensities, most likely associated with methanol, were removed with the SQUEEZE [Spek (2015). Acta Cryst. C71, 9–18] algorithm. PMID:26958368

  14. CO2 capture and separation from N2/CH4 mixtures by Co@B8/Co@B8(-) and M@B9/M@B9(-) (M = Ir, Rh, Ru) clusters: a theoretical study.

    PubMed

    Wang, Weihua; Zhang, Xiaoxiao; Li, Ping; Sun, Qiao; Li, Zhen; Ren, Cong; Guo, Chao

    2015-01-29

    The discovery of advanced materials with high selectivity and efficiency is essential to realize practical carbon capture and sequestration. Here, we have investigated the interactions of the Co@B8/Co@B8(-) and M@B9/M@B9(-) (M = Ir, Rh, Ru) clusters with CO2, N2, and CH4 gas molecules theoretically. We found that neutral boron clusters have weak interaction with CO2, N2, and CH4 molecules. Similarly, the clusters with their negative charge states have also weak interaction with N2 and CH4 molecules. However, anionic clusters have a strong interaction with CO2, which can be explained by the Lewis acid-base interaction as CO2 (Lewis acid) can gain electron easily from the electron-rich anionic clusters. Moreover, the kinetic stability of the formed complexes after CO2 capture has been validated by ab initio molecular dynamics. In all, the present study demonstrates, for the first time, that the anionic boron wheel ring clusters can be used as potential advanced materials for CO2 capture and separation from flue gas and natural gas mixtures. PMID:25594368

  15. Anomalous Stoichiometry Layered Structure and Magnetic Ordering of the Prussian Blue Analog [NEt4]2MnII3(CN)8

    SciTech Connect

    J Her; P Stephens; C Kareis; J Moore; J Miller

    2011-12-31

    Atypical of Prussian blue structured materials, Mn{sup II} and [NEt{sub 4}]CN react to form [NEt{sub 4}]{sub 2}Mn{sub 3}(CN){sub 8} possessing layers of octahedral [Mn{sup II}(CN){sub 6}]{sup 4-} bonded to two high-spin tetrahedral Mn{sup II} sites.

  16. The halogen-bonded adduct 1,4-bis(pyri-din-4-yl)buta-1,3-diyne-1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-hexa-deca-fluoro-1,8-diiodo-octane (1/1).

    PubMed

    Cavallo, Gabriella; Marras, Giovanni; Metrangolo, Pierangelo; Pilati, Tullio; Terraneo, Giancarlo

    2013-03-01

    In the crystal structure of the title compound, C8F16I2·C14H8N2, the mol-ecules form infinite chains parallel to [2-11] through two symmetry-independent C-I⋯N halogen bonds (XBs). As commonly found, the perfluoro-alkyl mol-ecules segregate from the hydro-carbon ones, forming a layered structure. Apart from the XBs, the only contact below the sum of van der Waals radii is a weak H⋯F contact. The topology of the network is a nice example of the paradigm of the expansion of ditopic starting modules; the XB leads to the construction of infinite supramolecular chains along [2-11] formed by alternating XB donors and acceptors. PMID:23476525

  17. The decomposition of the beta phase in Ti-44Al-8Nb and Ti-44Al-4Nb-4Zr-0.2Si alloys

    SciTech Connect

    Cheng, T.T.; Loretto, M.H.

    1998-08-10

    The decomposition of the beta phase has been studied in Ti-44Al-8Nb and Ti-44Al-4Nb-4Zr-0.2Si alloys cooled from the ({alpha} + {beta}) phase field using TEM and SEM. The morphology of the transformation products is shown to be sensitive to cooling rate and the results of the microstructural observations are used to construct a schematic continuous cooling transformation (CCT) diagram for these alloys. It is shown that under slow cooling, the beta phase is mainly consumed by the neighboring alpha grains via {alpha}/{beta} interfacial migration. During the subsequent {alpha} {yields} {alpha} + {gamma} transformation which occurs at lower temperatures and produces a lamellar microstructure, the retained beta phase can transform partially to {gamma} by a process analogous to the discontinuous coarsening of {gamma} lamellae. It has also been shown that, at higher cooling rates, the beta phase can decompose to alpha via secondary lath formation and/or a Widmanstaetten transformation although transformation by {alpha}/{beta} interfacial migration still occurs. The decomposition of beta directly to faceted gamma has also been observed both in slowly cooled and rapidly cooled materials. In the slowly cooled materials this is attributed to direct nucleation of gamma grains, whereas in the rapidly cooled materials they are thought to be the result of discontinuous coarsening. Furthermore, a B2 to {omega} transformation occurs readily in these alloys at temperatures higher than 700 C in both cases. Possible mechanisms for each of these transformations are discussed.

  18. Density functional theory calculations of UO2 oxidation: evolution of UO(2+x), U4O(9-y), U3O7, and U3O8.

    PubMed

    Andersson, D A; Baldinozzi, G; Desgranges, L; Conradson, D R; Conradson, S D

    2013-03-01

    Formation of hyperstoichiometric uranium dioxide, UO2+x, derived from the fluorite structure was investigated by means of density functional theory (DFT) calculations. Oxidation was modeled by adding oxygen atoms to UO2 fluorite supercells. For each compound ab initio molecular dynamics simulations were performed to allow the ions to optimize their local geometry. A similar approach was used for studying the reduction of U3O8. In agreement with the experimental phase diagram we identify stable line compounds at the U4O9-y and U3O7 stoichiometries. Although the transition from fluorite to the layered U3O8 structure occurs at U3O7 (UO2.333) or U3O7.333 (UO2.444), our calculated low temperature phase diagram indicates that the fluorite derived compounds are favored up to UO2.5, that is, as long as the charge-compensation for adding oxygen atoms occurs via formation of U(5+) ions, after which the U3O8-y phase becomes more stable. The most stable fluorite UO2+x phases at low temperature (0 K) are based on ordering of split quad-interstitial oxygen clusters. Most existing crystallographic models of U4O9 and U3O7, however, apply the cuboctahedral cluster. To better understand these discrepancies, the new structural models are analyzed in terms of existing neutron diffraction data. DFT calculations were also performed on the experimental cuboctahedral based U4O9-y structure, which enable comparisons between the properties of this phase with the quad-interstitial ones in detail. PMID:23406007

  19. 1-(3-Hy­droxy-5,8-dimeth­oxy-4-methyl-1,2,3,4-tetra­hydro-1,4-ep­oxy­naphthalen-2-yl)ethan-1-one

    PubMed Central

    Lough, Alan J.; Nagireddy, Jaipal R.; Tam, William

    2014-01-01

    The stereochemistry and regioschemistry (exo) of the title compound, C15H18O5, were determined by the X-ray analysis. The meth­oxy groups essentially lie in the plane of the benzene ring to which they are attached, as described by the C—O—C C torsion angles of −176.80 (12) and 4.67 (19)°. In the crystal, O—H⋯O hydrogen bonds and weak C—H⋯O hydrogen bonds link the mol­ecules, forming chains of R 2 1(8) rings along [010]. PMID:24860353

  20. Activity of 8F4, a T-cell receptor-like anti-PR1/HLA-A2 antibody, against primary human AML in vivo.

    PubMed

    Sergeeva, A; He, H; Ruisaard, K; St John, L; Alatrash, G; Clise-Dwyer, K; Li, D; Patenia, R; Hong, R; Sukhumalchandra, P; You, M J; Gagea, M; Ma, Q; Molldrem, J J

    2016-07-01

    The PR1 peptide, derived from the leukemia-associated antigens proteinase 3 and neutrophil elastase, is overexpressed on HLA-A2 in acute myeloid leukemia (AML). We developed a high-affinity T-cell receptor-like murine monoclonal antibody, 8F4, that binds to the PR1/HLA-A2 complex, mediates lysis of AML and inhibits leukemia colony formation. Here, we explored whether 8F4 was active in vivo against chemotherapy-resistant AML, including secondary AML. In a screening model, coincubation of AML with 8F4 ex vivo prevented engraftment of all tested AML subtypes in immunodeficient NSG (NOD scid IL-2 receptor γ-chain knockout) mice. In a treatment model of established human AML, administration of 8F4 significantly reduced or eliminated AML xenografts and extended survival compared with isotype antibody-treated mice. Moreover, in secondary transfer experiments, mice inoculated with bone marrow from 8F4-treated mice showed no evidence of AML engraftment, supporting the possible activity of 8F4 against the subset of AML with self-renewing potential. Our data provide evidence that 8F4 antibody is highly active in AML, including chemotherapy-resistant disease, supporting its potential use as a therapeutic agent in patients with AML. PMID:27055866

  1. (NH4)2WTe2O8 at 5.09 GPa: a single-crystal study using synchrotron radiation.

    PubMed

    Grzechnik, A; Halasyamani, P S; Kim, J H; Friese, K

    2010-07-01

    The polar crystal structure of diammonium [octaoxidoditellurato(IV)]tungstate, (NH(4))(2)WTe(2)O(8), was studied at high pressures using single-crystal X-ray diffraction in a diamond-anvil cell at the HASYLAB synchrotron (DESY, Hamburg, Germany). No phase transition was observed up to 7.16 GPa. However, a full structure determination at 5.09 GPa shows that the coordination number of one of the two non-equivalent Te atoms has decreased from four to three. PMID:20603546

  2. Direct white-light from core-shell-like sphere with Sr3Mg-Si2O8: Eu2+, Mn2+ coated on Sr2SiO4:Eu2+

    NASA Astrophysics Data System (ADS)

    Li, Jian; Deng, Jia-chun; Lu, Qi-fei; Wang, Da-jian

    2013-07-01

    A method of color mixture for white light is presented with Sr3MgSi2O8:Eu2+, Mn2+ shell coated on Sr2SiO4:Eu2+ core by spray pyrolysis procedure. Upon near ultraviolet (NUV) excitation, a 550 nm band emission of Eu2+ from core host combines with the simultaneous emissions of Eu2+ at 457 nm and Mn2+ at 683 nm based on energy transfer in the shell lattice to generate warm white light with color rendering index (CRI) of 91. With such a core-shell-like structure, the re-absorption of blue light from shell layer can be effectively suppressed, and the chemical stability of the phosphor is verified experimentally to be superior to that of the Sr2SiO4:Eu2+. This new proposed phosphor provides great potential in the color mixture of blending-free phosphor converted white NUV light emitting diode (LED) devices.

  3. 2-Amino-4-(4-chloro-phen-yl)-5-oxo-5,6,7,8-tetra-hydro-4H-chromene-3-carbonitrile.

    PubMed

    Mohamed, Shaaban K; Akkurt, Mehmet; Abdelhamid, Antar A; Singh, Kuldip; Allahverdiyev, M A

    2012-05-01

    In the title moleclue, C(16)H(13)ClN(2)O(2), the cyclo-hexene ring is in a sofa conformation. The pyran ring is essentialy planar [maximum deviation = 0.038 (2) Å] and forms a dihedral angle of 89.68 (10)° with the benzene ring. In the crystal, mol-ecules are linked by pairs of N-H⋯N hydrogen bonds, forming inversion dimers with R(2) (2)(12) ring motifs. These dimers are further linked by N-H⋯O hydrogen bonds into chains along [110]. Weak C-H⋯O hydrogen bonds are also present. PMID:22590301

  4. (+)-2-(1,2,3,4,4a,5,6,7-Octahydro-4a,8-dimethyl-7-oxo-2-naphthyl)propionic acid: catemeric hydrogen bonding in a bicyclic sesquiterpenoid keto acid.

    PubMed

    Brunskill, Andrew P J; Thompson, Hugh W; Lalancette, Roger A

    2002-05-01

    The title compound, C(15)H(22)O(3), derived from a naturally occurring sesquiterpenoid, has two molecules in the asymmetric unit, differing principally in the rotational conformation of the carboxyl group. Each species aggregates separately as a carboxyl-to-ketone hydrogen-bonding catemer [O.O = 2.752 (4) and 2.682 (4) A, and O-H.O = 161 (4) and 168 (4) degrees ], producing two crystallographically independent single-strand hydrogen-bonding helices, with opposite end-to-end orientations, passing through the cell in the b direction. Three intermolecular C-H.O=C close contacts exist for the ketone. PMID:11983981

  5. Inclusion of a universal tetanus toxoid CD4+ T cell epitope P2 significantly enhanced the immunogenicity of recombinant rotavirus ΔVP8* subunit parenteral vaccines

    PubMed Central

    Wen, Xiaobo; Wen, Ke; Cao, Dianjun; Li, Guohua; Jones, Ronald W.; Li, Jianping; Szu, Shousun; Hoshino, Yasutaka; Yuan, Lijuan

    2014-01-01

    Currently available live oral rotavirus vaccines, Rotarix® and RotaTeq®, are highly efficacious in developed countries. However, the immunogenicity and efficacy of such vaccines in some developing countries are low. We reported previously that bacterially-expressed rotavirus ΔVP8* subunit vaccine candidates with P[8], P[4] or P[6] specificity elicited high-titer virus neutralizing antibodies in animals immunized intramuscularly. Of note was the finding that antibodies induced with the P[8]ΔVP8* vaccine neutralized both homotypic P[8] and heterotypic P[4] rotavirus strains to high titer. To further improve its vaccine potential, a tetanus toxoid universal CD4+ T cell epitope P2 was introduced into P[8] or P[6]ΔVP8* construct. The resulting recombinant fusion proteins expressed in Escherichia coli were of high solubility and were produced with high yield. Two doses (10 or 20μg/dose) of the P2-P[8]ΔVP8* vaccine or P2-P[6]ΔVP8* vaccine with aluminum phosphate adjuvant elicited significantly higher geometric mean homologous neutralizing antibody titers than the vaccines without P2 in intramuscularly immunized guinea pigs. Interestingly, high levels of neutralizing antibody responses induced in guinea pigs with 3 doses of the P2-P[8]ΔVP8* vaccine persisted for at least 6 months. Furthermore, in the gnotobiotic piglet challenge study, three intramuscular doses (50μg/dose) of the P2-P[8]ΔVP8* vaccine with aluminum phosphate adjuvant significantly delayed the onset of diarrhea and significantly reduced the duration of diarrhea and the cumulative diarrhea score after oral challenge with virulent human rotavirus Wa (G1P[8]) strain. The P2-P[8]ΔVP8* vaccine induced serum virus neutralizing antibody and VP4-specific IgG antibody production prechallenge, and primed the pigs for higher antibody and intestinal and systemic virus-specific IFN-γ producing CD4+ T cell responses postchallenge. These two subunit vaccines could be used at a minimum singly or preferably in

  6. 2-Amino-4-(4-chloro­phen­yl)-5-oxo-5,6,7,8-tetra­hydro-4H-chromene-3-carbonitrile

    PubMed Central

    Mohamed, Shaaban K.; Akkurt, Mehmet; Abdelhamid, Antar A.; Singh, Kuldip; Allahverdiyev, M. A.

    2012-01-01

    In the title moleclue, C16H13ClN2O2, the cyclo­hexene ring is in a sofa conformation. The pyran ring is essentialy planar [maximum deviation = 0.038 (2) Å] and forms a dihedral angle of 89.68 (10)° with the benzene ring. In the crystal, mol­ecules are linked by pairs of N—H⋯N hydrogen bonds, forming inversion dimers with R 2 2(12) ring motifs. These dimers are further linked by N—H⋯O hydrogen bonds into chains along [110]. Weak C—H⋯O hydrogen bonds are also present. PMID:22590301

  7. Synthesis and photoluminescence properties of near-UV pumped yellow-emitting Li3Ba2La3(WO4)8:Dy3+ phosphors

    NASA Astrophysics Data System (ADS)

    Wang, G. Q.; Gong, X. H.; Chen, Y. J.; Huang, J. H.; Lin, Y. F.; Luo, Z. D.; Huang, Y. D.

    2014-05-01

    Li3Ba2La3(WO4)8:Dy3+ yellow-emitting phosphors were synthesized by the solid state reaction method. These phosphors exhibit one intense emission band around 575 nm under excitation at 365 nm. The dependences of the emission intensities and the chromaticity coordinates on Dy3+ concentration were analyzed. The optimum doping concentration of Dy3+ for the phosphor is about 6 mol% and the corresponding chromaticity coordinates is (0.435, 0.476) at room temperature. Besides, the Li3Ba2La3(WO4)8:Dy3+ phosphor shows higher thermal stability than that of (Sr, Ba)2SiO4:Eu2+. The results show that the Li3Ba2La3(WO4)8:Dy3+ phosphor with strong yellow emission may be applied in near ultraviolet pumped white LEDs.

  8. 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

  9. Myeloid-related protein 8 induces self-tolerance and cross-tolerance to bacterial infection via TLR4- and TLR2-mediated signal pathways

    PubMed Central

    Coveney, Andrew P.; Wang, Wei; Kelly, Justin; Hua Liu, Jing; Blankson, Siobhan; Di Wu, Qiong; Paul Redmond, H.; Huai Wang, Jiang

    2015-01-01

    Myeloid-related protein 8 (Mrp8) is the active component of Mrp8/14 protein complex released by phagocytes at the site of infection and stimulates inflammatory responses. However, it is unclear whether Mrp8 could induce self-tolerance and cross-tolerance to bacterial infection. Here we report that Mrp8 triggered TNF-α and IL-6 release via a Toll-like receptor 4 (TLR4)-dependent manner. Pre-stimulation of murine macrophages and human monocytes with Mrp8 induced self-tolerance to Mrp8 re-stimulation and cross-tolerance to lipopolysaccharide (LPS), bacterial lipoprotein (BLP), gram-negative and gram-positive bacterial challenges, with substantially attenuated TNF-α and IL-6 release. Moreover, Mrp8 tolerisation significantly reduced serum TNF-α and IL-6, increased polymorphonuclear neutrophil (PMN) recruitment and accelerated bacterial clearance, thus protecting mice against LPS-induced lethality and cecal ligation and puncture (CLP)-induced polymicrobial sepsis. In addition to TLR4, TLR2 also contributed to Mrp8-induced inflammatory response and tolerance. Down-regulation of phosphorylated p38 by Mrp8 pre-stimulation was predominantly responsible for the intracellular mechanism of Mrp8-induced tolerance. Thus, our findings of Mrp8-induced self-tolerance and cross-tolerance may provide a potential strategy for attenuating an overwhelming proinflammatory cascade and enhancing antimicrobial responses during microbial sepsis. PMID:26329314

  10. mTOR Complex Signaling through the SEMA4A–Plexin B2 Axis Is Required for Optimal Activation and Differentiation of CD8+ T Cells

    PubMed Central

    Ito, Daisuke; Nishide, Masayuki; Okuno, Tatsusada; Takamatsu, Hyota; Kang, Sujin; Kimura, Tetsuya; Yoshida, Yuji; Morimoto, Keiko; Maeda, Yohei; Hosokawa, Takashi; Toyofuku, Toshihiko; Ohshima, Jun; Kamimura, Daisuke; Yamamoto, Masahiro; Murakami, Masaaki; Morii, Eiichi; Rakugi, Hiromi; Isaka, Yoshitaka

    2015-01-01

    Mammalian target of rapamycin (mTOR) plays crucial roles in activation and differentiation of diverse types of immune cells. Although several lines of evidence have demonstrated the importance of mTOR-mediated signals in CD4+ T cell responses, the involvement of mTOR in CD8+ T cell responses is not fully understood. In this study, we show that a class IV semaphorin, SEMA4A, regulates CD8+ T cell activation and differentiation through activation of mTOR complex (mTORC) 1. SEMA4A−/− CD8+ T cells exhibited impairments in production of IFN-γ and TNF-α and induction of the effector molecules granzyme B, perforin, and FAS-L. Upon infection with OVA-expressing Listeria monocytogenes, pathogen-specific effector CD8+ T cell responses were significantly impaired in SEMA4A−/− mice. Furthermore, SEMA4A−/− CD8+ T cells exhibited reduced mTORC1 activity and elevated mTORC2 activity, suggesting that SEMA4A is required for optimal activation of mTORC1 in CD8+ T cells. IFN-γ production and mTORC1 activity in SEMA4A−/− CD8+ T cells were restored by administration of recombinant Sema4A protein. In addition, we show that plexin B2 is a functional receptor of SEMA4A in CD8+ T cells. Collectively, these results not only demonstrate the role of SEMA4A in CD8+ T cells, but also reveal a novel link between a semaphorin and mTOR signaling. PMID:26116513

  11. Turtle sex determination assay: Mass balance and responses to 2,3,7,8-tetrachlorodibenzo-p-dioxin and 3,3',4,4',5-pentachlorobiphenyl

    USGS Publications Warehouse

    Gale, Robert W.; Bergeron, Judith M.; Willingham, Emily J.; Crews, David

    2002-01-01

    Polyhalogenated hydrocarbons have been implicated in the anomalous sexual differentiation of mammals and reptiles. Here, a temperature-sensitive turtle sex determination assay using the red-eared slider (Trachemys scripta elegans) was used to determine the estrogenic or antiestrogenic activity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 3,3′,4,4′,5-pentachlorobiphenyl (PCB-126). Neither TCDD nor PCB-126 showed a statistically significant difference in the resulting sex ratios (Fisher's exact test, p < 0.45). As a consequence of the dosing technique (eggshell spotting), the shell retained 90 and 96% of the dose for PCB-126 and TCDD, respectively, similar to retention of estradiol-17β. However, the dosing allowed transfer of sufficient chemical to achieve tissue concentrations that were greater than most concentrations reported for environmentally incurred residues. Similar relative mass distributions of PCB-126 and TCDD were observed in albumin (14–20%), yolk (55–70%), and embryo (16–25%). Relative concentration distributions in the embryo approached those in the yolk, 37 to 40% and 40 to 52%, respectively, while relative concentrations in the albumin remained at 11 to 20%. Lipid-normalized TCDD and PCB-126 concentrations were 30- to 40-fold greater in the embryo than in the yolk. It is hypothesized that nonpassive partitioning processes may have occurred in the embryo.

  12. Synthesis of the enantiomers of XYLNAc and LYXNAc: comparison of β-N-acetylhexosaminidase inhibition by the 8 stereoisomers of 2-N-acetylamino-1,2,4-trideoxy-1,4-iminopentitols.

    PubMed

    Crabtree, Elizabeth V; Martínez, R Fernando; Nakagawa, Shinpei; Adachi, Isao; Butters, Terry D; Kato, Atsushi; Fleet, George W J; Glawar, Andreas F G

    2014-06-21

    The enantiomers of XYLNAc (2-N-acetylamino-1,2,4-trideoxy-1,4-iminoxylitol) are prepared from the enantiomers of glucuronolactone; the synthesis of the enantiomers of LYXNAc (2-N-acetylamino-1,2,4-trideoxy-1,4-iminolyxitol) from an L-arabinono-δ-lactone and a D-ribono-δ-lactone is reported. A comparison is made of the inhibition of β-N-acetylhexosaminidases (HexNAcases) and α-N-acetylgalactosaminidase (α-GalNAcase) by 8 stereoisomeric 2-N-acetylamino-1,2,4-trideoxy-1,4-iminopentitols; their N-benzyl derivatives are better inhibitors than the parent compounds. Both XYLNAc and LABNAc are potent inhibitors against HexNAcases. None of the compounds show any inhibition of α-GalNAcase. PMID:24802185

  13. 2-[6,8-Dibromo-3-(4-hy­droxy­cyclo­hex­yl)-1,2,3,4-tetra­hydro­quinazolin-2-yl]phenol methanol 0.25-solvate

    PubMed Central

    Wang, Zhi-Gang; Wang, Rong; Zhi, Feng; Wang, Ming-Li

    2011-01-01

    The title compound, C20H22Br2N2O2·0.25CH4O, was synthesized by the condensation reaction of salicyl­aldehyde with 4-(2-amino-3,5-dibromo­benzyl­amino)­cyclo­hexa­nol in methanol. There are four independent main mol­ecules and two half-occupied methanol solvent mol­ecules in the asymmetric unit. The dihedral angles between the two benzene rings in the four mol­ecules are 87.8 (6), 86.6 (6), 89.3 (6) and 83.1 (6)°. Each mol­ecule features an intra­molecular O—H⋯N hydrogen bond and a short N—H⋯Br link. In the crystal components are linked by O—H⋯O hydrogen bonds. PMID:21754095

  14. Study on energy transfer and energy migration of Ca2Gd8(SiO4)6O2:Dy3+ phosphor films.

    PubMed

    Wang, X Q; Han, X M; Zhen, C M

    2011-11-01

    Being a kind of rare-earth-metal silicate with oxidapatite structure, Ca2R8(SiO4)6O2 (R = Y, Gd, La) is a promising material doped with rare earth, and widely used as phosphors. In this thesis, Ca2Gd8(SiO4)6O2:Dy3+ films were prepared by the sol-gel method. X-ray diffraction (XRD), atomic force microscopy (AFM), photoluminescence (PL) spectra, and lifetimes were used to characterize the resulting films. AFM study indicated that the phosphor films consisted of 120 nm homogeneous particles. By combining the model of Burshtein for donor-donor migration and the V-F-B model for donor-acceptor energy transfer, the experimental luminescence decay curve of 6P(J) state of Gd3+ was re-simulated. It is found that concentration quenching of Gd3+ can be due to the result of the joint action of donor-donor (Gd3+-Gd3+) energy migration and donor-acceptor (Gd3+-Dy3+) energy transfer. PMID:22413278

  15. Growth, Thermal and Spectral Properties of Er3+-Doped and Er3+/Yb3+-Codoped Li3Ba2La3(WO4)8 Crystals

    PubMed Central

    Xiao, Bin; Lin, Zhoubin; Zhang, Lizhen; Huang, Yisheng; Wang, Guofu

    2012-01-01

    This paper reports the growth and spectral properties of Er3+-doped and Er3+/Yb3+-codoped Li3Ba2La3(WO4)8 crystals. The Er3+: Li3Ba2La3(WO4)8 crystal with dimensions of 56 mm×28 mm×9 mm and Er3+/Yb3+: Li3Ba2La3(WO4)8 crystal with dimensions of 52 mm×24 mm×8 mm were obtained by the top-seeded solution growth (TSSG) method. Thermal expansion coefficients and thermal conductivity of both crystals were measured. The spectroscopic characterizations of both crystals were investigated. The spectroscopic analysis reveals that the Er3+/Yb3+: Li3Ba2La3(WO4)8 crystal has much better optical properties than the Er3+: Li3Ba2La3(WO4)8 crystal, thus it may become a potential candidate for solid-state laser gain medium material. PMID:22808214

  16. 38 CFR 8a.4 - Coverage.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Coverage. 8a.4 Section 8a.4 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS VETERANS MORTGAGE LIFE INSURANCE § 8a.4 Coverage. (a) The amount of VMLI in force on his or her life at any one time shall...

  17. 38 CFR 8a.4 - Coverage.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Coverage. 8a.4 Section 8a.4 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS VETERANS MORTGAGE LIFE INSURANCE § 8a.4 Coverage. (a) The amount of VMLI in force on his or her life at any one time shall...

  18. 38 CFR 8a.4 - Coverage.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Coverage. 8a.4 Section 8a.4 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS VETERANS MORTGAGE LIFE INSURANCE § 8a.4 Coverage. (a) The amount of VMLI in force on his or her life at any one time shall...

  19. 38 CFR 8a.4 - Coverage.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Coverage. 8a.4 Section 8a.4 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS VETERANS MORTGAGE LIFE INSURANCE § 8a.4 Coverage. (a) The amount of VMLI in force on his or her life at any one time shall...

  20. 38 CFR 8a.4 - Coverage.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Coverage. 8a.4 Section 8a.4 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS AFFAIRS VETERANS MORTGAGE LIFE INSURANCE § 8a.4 Coverage. (a) The amount of VMLI in force on his or her life at any one time shall...

  1. 43 CFR 8.4 - Blocking out.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Blocking out. 8.4 Section 8.4 Public Lands: Interior Office of the Secretary of the Interior JOINT POLICIES OF THE DEPARTMENTS OF THE INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.4 Blocking out. Blocking out will be accomplished...

  2. 43 CFR 8.4 - Blocking out.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Blocking out. 8.4 Section 8.4 Public Lands: Interior Office of the Secretary of the Interior JOINT POLICIES OF THE DEPARTMENTS OF THE INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.4 Blocking out. Blocking out will be accomplished...

  3. 43 CFR 8.4 - Blocking out.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Blocking out. 8.4 Section 8.4 Public Lands: Interior Office of the Secretary of the Interior JOINT POLICIES OF THE DEPARTMENTS OF THE INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.4 Blocking out. Blocking out will be accomplished...

  4. 43 CFR 8.4 - Blocking out.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Blocking out. 8.4 Section 8.4 Public Lands: Interior Office of the Secretary of the Interior JOINT POLICIES OF THE DEPARTMENTS OF THE INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.4 Blocking out. Blocking out will be accomplished...

  5. 43 CFR 8.4 - Blocking out.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Blocking out. 8.4 Section 8.4 Public Lands: Interior Office of the Secretary of the Interior JOINT POLICIES OF THE DEPARTMENTS OF THE INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.4 Blocking out. Blocking out will be accomplished...

  6. 15 CFR 8b.4 - Discrimination prohibited.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Discrimination prohibited. 8b.4 Section 8b.4 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION AGAINST THE HANDICAPPED IN FEDERALLY ASSISTED PROGRAMS OPERATED BY THE DEPARTMENT OF COMMERCE General Provisions § 8b.4 Discrimination prohibited....

  7. 15 CFR 8b.4 - Discrimination prohibited.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 1 2013-01-01 2013-01-01 false Discrimination prohibited. 8b.4 Section 8b.4 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION... Provisions § 8b.4 Discrimination prohibited. (a) General. No qualified handicapped individual shall, on...

  8. 15 CFR 8b.4 - Discrimination prohibited.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 1 2014-01-01 2014-01-01 false Discrimination prohibited. 8b.4 Section 8b.4 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION... Provisions § 8b.4 Discrimination prohibited. (a) General. No qualified handicapped individual shall, on...

  9. 15 CFR 8b.4 - Discrimination prohibited.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 1 2012-01-01 2012-01-01 false Discrimination prohibited. 8b.4 Section 8b.4 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION... Provisions § 8b.4 Discrimination prohibited. (a) General. No qualified handicapped individual shall, on...

  10. 15 CFR 8b.4 - Discrimination prohibited.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Discrimination prohibited. 8b.4 Section 8b.4 Commerce and Foreign Trade Office of the Secretary of Commerce PROHIBITION OF DISCRIMINATION... Provisions § 8b.4 Discrimination prohibited. (a) General. No qualified handicapped individual shall, on...

  11. 28 CFR 4.8 - Hearing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 28 Judicial Administration 1 2011-07-01 2011-07-01 false Hearing. 4.8 Section 4.8 Judicial... OF 1974 § 4.8 Hearing. The hearing on the application shall be held at the offices of the Commision in Washington, DC, or elsewhere as the Commission may direct. The hearing shall be held before...

  12. 28 CFR 4.8 - Hearing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 28 Judicial Administration 1 2010-07-01 2010-07-01 false Hearing. 4.8 Section 4.8 Judicial... OF 1974 § 4.8 Hearing. The hearing on the application shall be held at the offices of the Commision in Washington, DC, or elsewhere as the Commission may direct. The hearing shall be held before...

  13. 1 CFR 8.4 - Indexes.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 1 General Provisions 1 2014-01-01 2012-01-01 true Indexes. 8.4 Section 8.4 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.4 Indexes. A subject index to the entire Code shall be annually revised and...

  14. 1 CFR 8.4 - Indexes.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 1 General Provisions 1 2011-01-01 2011-01-01 false Indexes. 8.4 Section 8.4 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.4 Indexes. A subject index to the entire Code shall be annually revised and...

  15. 1 CFR 8.4 - Indexes.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 1 General Provisions 1 2010-01-01 2010-01-01 false Indexes. 8.4 Section 8.4 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.4 Indexes. A subject index to the entire Code shall be annually revised and...

  16. 1 CFR 8.4 - Indexes.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 1 General Provisions 1 2013-01-01 2012-01-01 true Indexes. 8.4 Section 8.4 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.4 Indexes. A subject index to the entire Code shall be annually revised and...

  17. 1 CFR 8.4 - Indexes.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 1 General Provisions 1 2012-01-01 2012-01-01 false Indexes. 8.4 Section 8.4 General Provisions ADMINISTRATIVE COMMITTEE OF THE FEDERAL REGISTER SPECIAL EDITIONS OF THE FEDERAL REGISTER CODE OF FEDERAL REGULATIONS § 8.4 Indexes. A subject index to the entire Code shall be annually revised and...

  18. Synthesis of 2-amino-8-chloro-4-phenyl-5,11-dihydro-6H-pyrido[2,3-a]carbazole-3-carbonitrile: Structural and biological evaluation

    NASA Astrophysics Data System (ADS)

    Indumathi, Thangavel; Fronczek, Frank R.; Rajendra Prasad, K. J.

    2012-05-01

    The title compound 2-amino-8-chloro-4-phenyl-5,11-dihydro-6H-pyrido[2,3-a]carbazole-3-carbonitrile was prepared in good yield by multicomponent reaction under L-proline as promoter structure of the prepared compound was studied and characterized using IR, 1H and 13C NMR spectroscopic techniques. The crystal structure of the compound was determined by X-ray diffraction on single crystals. The spectroscopic experimental evidences strongly suggested that the compound could interact with calf thymus DNA (CT-DNA) through intercalation. The cytotoxicity was evaluated by Sulforhodamine B assay against A-549, B16F10, HCT-15, SKMel2 and SKOV3 cell lines and compared with standard drug cisplatin. The title compound bearing the chloro group depicted better and selective cytotoxicity against SKMel2 cell line. The compound showed moderate capacity for scavenging DPPH.

  19. Solvation effects on reactive intermediates: The benzyl radical and its clusters with Ar, N2, CH4, C2H6, and C3H8

    NASA Astrophysics Data System (ADS)

    Disselkamp, R.; Bernstein, E. R.

    1993-03-01

    Mass resolved excitation spectra are presented for the benzyl radical and its clusters with Ar, N2, CH4, C2H6, and C3H8. The cluster spectra exhibit small redshifts (≤50 cm-1) relative to the unclustered benzyl radical for the D1(1 2A2)←D0(1 2B2) and D2(2 2B2)←D0(1 2B2) electronic transition regions. A unique set of low energy van der Waals modes is observed for these clusters for each excited electronic state investigated. The cluster spectra also reveal significant vibronic coupling between the two excited electronic states of the benzyl radical, as evidenced by a single vibrational predissociation threshold for each cluster. Ab initio calculations are performed on the benzyl radical to examine excited electronic state structure, predict transition energies, estimate ionization energy, and determine partial atomic charges in the electronic states of interest. The resulting partial charges are used in empirical atom-atom potential energy calculations to aid in the understanding of cluster spectroscopic shifts, binding energies, and van der Waals modes.

  20. In vitro studies on the influence of L-ascorbic acid 2-[3,4-dihydro- 2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6yl-hy drogen phosphate] potassium salt on lipid peroxidation and phospholipase A2 activity.

    PubMed

    Kuribayashi, Y; Yoshida, K; Sakaue, T; Okumura, A

    1992-09-01

    The effects of L-ascorbic acid 2-[3,4-dihydro-2,5,7,8-tetramethyl-2- (4,8,12-trimethyltridecyl)-2H-1-benzopyran-6yl-hydrogen phosphate] potassium salt (EPC-K1, CAS 127061-56-7), a new compound for ischemia-reperfusion injuries, on lipid peroxidation and phospholipase A2 activity were studied in vitro using rat brain homogenates and human plasma. EPC-K1 inhibited phospholipase A2 activity in human plasma in a concentration-dependent manner (IC50 = 7.3 x 10(-4) mol/l), whereas a mixture of alpha-tocopherol and ascorbic acid did not exhibit this effect. In rat brain homogenates, EPC-K1 also inhibited lipid peroxidation in a concentration-dependent manner (IC50 = 2.3 x 10(-6) mol/l). alpha-Tocopherol was less active than EPC-K1. These properties of EPC-K1 suggest that EPC-K1 may prove useful in the treatment of ischemia-reperfusion injuries. PMID:1445471

  1. BaCdSnS4 and Ba3CdSn2S8: syntheses, structures, and non-linear optical and photoluminescence properties.

    PubMed

    Zhen, Ni; Wu, Kui; Wang, Ying; Li, Qiang; Gao, Wenhui; Hou, Dianwei; Yang, Zhihua; Jiang, Huaidong; Dong, Yongjun; Pan, Shilie

    2016-06-28

    Two non-centrosymmetric metal chalcogenides, BaCdSnS4 and Ba3CdSn2S8, were synthesized using a high temperature solid-state reaction in an evacuated silica tube. Although the two compounds have the same building units in their structures, namely CdS4, SnS4 and BaS8 units, both of them have different structures. BaCdSnS4 crystallizes in the orthorhombic space group Fdd2 and its structure can be characterized by the two-dimensional ∞[Cd-Sn-S] layers composed of corner- and edge-sharing CdS4 and SnS4 tetrahedra with Ba atoms located between the two adjacent ∞[Cd-Sn-S] layers. Ba3CdSn2S8 crystallizes in the space group I4[combining macron]3d of the orthorhombic system and the CdS4 and SnS4 groups are connected with each other via corner-sharing to form a three-dimensional framework, which is different from the 2D ∞[Cd-Sn-S] layer structure in BaCdSnS4. The UV-vis-NIR diffuse-reflectance spectra show that the experimental band gaps are about 2.30 eV for BaCdSnS4 and 2.75 eV for Ba3CdSn2S8, respectively. IR and Raman measurement results indicate that their transparent ranges are up to 25 μm. Second-order NLO measurements show that BaCdSnS4 exhibits strong powder second-harmonic generation (SHG) intensities at 2.09 μm laser pumping that are ∼5 and 0.7 times that of AgGaS2 in the particle size 38-55 and 150-200 μm, respectively, whereas Ba3CdSn2S8 only exhibits SHG intensities of about 0.8 and 0.1 times that of AgGaS2 at the same particle sizes. The origin of the NLO response in BaCdSnS4 may originate from the macroscopic arrangement of the SnS4 and CdS4 tetrahedra. Furthermore, the photoluminescence properties of the two compounds have also been investigated and show obvious blue and green light emission. PMID:27272926

  2. Crystal structures and color properties of new complex perovskite oxynitrides AMg0.2Ta0.8O2.6N0.4 (A = Sr, Ba).

    PubMed

    Moon, Keon-Ho; Kim, Jung-Mi; Sohn, Youngku; Cho, Dae Won; Kim, Young-Il; Avdeev, Maxim

    2016-04-01

    New complex perovskite oxynitrides AMg0.2Ta0.8O2.6N0.4 (A = Sr, Ba) were synthesized by reacting A5Ta4O15 with MgCl2 in flowing NH3. The formation of AMg0.2Ta0.8O2.6N0.4 can be described as the cooperative insertion of Mg(2+) + 2N(3-) and the release of 2O(2-) from the layered oxide, A5Ta4O15. Rietveld refinement of the neutron and synchrotron X-ray diffraction patterns indicated that BaMg0.2Ta0.8O2.6N0.4 is simple cubic (Pm3[combining macron]m) and SrMg0.2Ta0.8O2.6N0.4 is body-centered tetragonal (I4/mcm), isostructural with BaM0.2Ta0.8O2.8N0.2 and SrM0.2Ta0.8O2.8N0.2 (M = Li, Na), respectively. The nitrogen in SrMg0.2Ta0.8O2.6N0.4 is partially ordered favoring the c-axial site over the ab-plane of the tetragonal cell, which is a different O/N order pattern from that of SrLi0.2Ta0.8O2.8N0.2 and SrNa0.2Ta0.8O2.8N0.2. The group of simple and complex perovskites, ATaO2N, ALi0.2Ta0.8O2.8N0.2, ANa0.2Ta0.8O2.8N0.2, and AMg0.2Ta0.8O2.6N0.4 (A = Sr, Ba) covers the band gap range, 1.9-2.4 eV, and the color ranges from yellow to dark brown. PMID:26918699

  3. An ER Complex of ODR-4 and ODR-8/Ufm1 Specific Protease 2 Promotes GPCR Maturation by a Ufm1-Independent Mechanism

    PubMed Central

    Chen, Changchun; Itakura, Eisuke; Weber, Katherine P.; Hegde, Ramanujan S.; de Bono, Mario

    2014-01-01

    Despite the importance of G-protein coupled receptors (GPCRs) their biogenesis is poorly understood. Like vertebrates, C. elegans uses a large family of GPCRs as chemoreceptors. A subset of these receptors, such as ODR-10, requires the odr-4 and odr-8 genes to be appropriately localized to sensory cilia. The odr-4 gene encodes a conserved tail-anchored transmembrane protein; the molecular identity of odr-8 is unknown. Here, we show that odr-8 encodes the C. elegans ortholog of Ufm1-specific protease 2 (UfSP2). UfSPs are cysteine proteases identified biochemically by their ability to liberate the ubiquitin-like modifier Ufm1 from its pro-form and protein conjugates. ODR-8/UfSP2 and ODR-4 are expressed in the same set of twelve chemosensory neurons, and physically interact at the ER membrane. ODR-4 also binds ODR-10, suggesting that an ODR-4/ODR-8 complex promotes GPCR folding, maturation, or export from the ER. The physical interaction between human ODR4 and UfSP2 suggests that this complex's role in GPCR biogenesis may be evolutionarily conserved. Unexpectedly, mutant versions of ODR-8/UfSP2 lacking catalytic residues required for protease activity can rescue all odr-8 mutant phenotypes tested. Moreover, deleting C. elegans ufm-1 does not alter chemoreceptor traffic to cilia, either in wild type or in odr-8 mutants. Thus, UfSP2 proteins have protease- and Ufm1-independent functions in GPCR biogenesis. PMID:24603482

  4. Bystander Activation and Anti-Tumor Effects of CD8+ T Cells Following Interleukin-2 Based Immunotherapy Is Independent of CD4+ T Cell Help

    PubMed Central

    Grossenbacher, Steven K.; Hsiao, Hui-Hua; Zamora, Anthony E.; Mirsoian, Annie; Koehn, Brent; Blazar, Bruce R.; Weiss, Jonathan M.; Wiltrout, Robert H.; Sckisel, Gail D.; Murphy, William J.

    2014-01-01

    We have previously demonstrated that immunotherapy combining agonistic anti-CD40 and IL-2 (IT) results in synergistic anti-tumor effects. IT induces expansion of highly cytolytic, antigen-independent “bystander-activated” (CD8+CD44high) T cells displaying a CD25−NKG2D+ phenotype in a cytokine dependent manner, which were responsible for the anti-tumor effects. While much attention has focused on CD4+ T cell help for antigen-specific CD8+ T cell expansion, little is known regarding the role of CD4+ T cells in antigen-nonspecific bystander-memory CD8+ T cell expansion. Utilizing CD4 deficient mouse models, we observed a significant expansion of bystander-memory T cells following IT which was similar to the non-CD4 depleted mice. Expanded bystander-memory CD8+ T cells upregulated PD-1 in the absence of CD4+ T cells which has been published as a hallmark of exhaustion and dysfunction in helpless CD8+ T cells. Interestingly, compared to CD8+ T cells from CD4 replete hosts, these bystander expanded cells displayed comparable (or enhanced) cytokine production, lytic ability, and in vivo anti-tumor effects suggesting no functional impairment or exhaustion and were enriched in an effector phenotype. There was no acceleration of the post-IT contraction phase of the bystander memory CD8+ response in CD4-depleted mice. The response was independent of IL-21 signaling. These results suggest that, in contrast to antigen-specific CD8+ T cell expansion, CD4+ T cell help is not necessary for expansion and activation of antigen-nonspecific bystander-memory CD8+ T cells following IT, but may play a role in regulating conversion of these cells from a central memory to effector phenotype. Additionally, the expression of PD-1 in this model appears to be a marker of effector function and not exhaustion. PMID:25119341

  5. Crystal chemistry of anhydrous Li uranyl phosphates and arsenates. II. Tubular fragments and cation-cation interactions in the 3D framework structures of Li 6[(UO 2) 12(PO 4) 8(P 4O 13)], Li 5[(UO 2) 13(AsO 4) 9(As 2O 7)], Li[(UO 2) 4(AsO 4) 3] and Li 3[(UO 2) 7(AsO 4) 5O)

    NASA Astrophysics Data System (ADS)

    Alekseev, Evgeny V.; Krivovichev, Sergey V.; Depmeier, Wulf

    2009-11-01

    Single crystals of the new compounds Li 6[(UO 2) 12(PO 4) 8(P 4O 13)] ( 1), Li 5[(UO 2) 13(AsO 4) 9(As 2O 7)] ( 2), Li[(UO 2) 4(AsO 4) 3] ( 3) and Li 3[(UO 2) 7(AsO 4) 5O)] ( 4) have been prepared using high-temperature solid state reactions. The crystal structures have been solved by direct methods: 1—monoclinic, C2/ m, a=26.963(3) Å, b=7.063(1) Å, c=19.639(1) Å, β=126.890(4)°, V=2991.2(6) Å 3, Z=2, R1=0.0357 for 3248 unique reflections with | F0|≥4 σ F; 2—triclinic, P1¯, a=7.1410(8) Å, b=13.959(1) Å, c=31.925(1) Å, α=82.850(2)°, β=88.691(2)°, γ=79.774(3)°, V=3107.4(4) Å 3, Z=2, R1=0.0722 for 9161 unique reflections with | F0|≥4 σ F; 3—tetragonal, I4 1/ amd, a=7.160(3) Å, c=33.775(9) Å, V=1732(1) Å 3, Z=4, R1=0.0356 for 318 unique reflections with | F0|≥4 σ F; 4—tetragonal, P4¯, a=7.2160(5) Å, c=14.6540(7) Å, V=763.04(8) Å 3, Z=1, R1=0.0423 for 1600 unique reflections with | F0|≥4 σ F. Structures of all the phases under consideration are based on complex 3D frameworks consisting of different types of uranium polyhedra (UO 6 and UO 7) and different types of tetrahedral TO 4 anions ( T=P or As): PO 4 and P 4O 13 in 1, AsO 4 and As 2O 7 in 2, and single AsO 4 tetrahedra in 3 and 4. In the structures of 1 and 2, UO 7 pentagonal bipyramids share edges to form (UO 5) ∞ chains extended along the b axis in 1 and along the a axis in 2. The chains are linked via single TO 4 tetrahedra into tubular units with external diameters of 11 Å in 1 and 11.5 Å in 2, and internal diameters of 4.1 Å in 1 and 4.5 Å in 2. The channels accommodate Li + cations. The tubular units are linked into 3D frameworks by intertubular complexes. Structures of 3 and 4 are based on 3D frameworks composed on layers united by (UO 5) ∞ infinite chains. Cation-cation interactions are observed in 2, 3, and 4. In 2, the structure contains a trimeric unit with composition [OU(1)O]-U(13)-[OU(2)O]. In the structures of 3 and 4, T-shaped dimers are

  6. Ring-strain release in neutral and dicationic 7,8,17,18-tetra-bromo-5,10,15,20-tetra-phenyl-porphyrin: crystal structures of C44H26Br4N4 and C44H28Br4N4 (2+)·2ClO4 (-)·3CH2Cl2.

    PubMed

    Scheidt, W Robert; Duval, Hugues F; Oliver, Allen G

    2016-06-01

    Two porphyrin complexes were studied to determine the effects of protonation on ring deformation within the porphyrin. The porphyrin 7,8,17,18-tetra-bromo-5,10,15,20-tetra-phenyl-porphyrin, C44H26Br4N4, was selected because the neutral species is readily doubly protonated to yield a dication, which was crystallized here with perchlorate counter-ions as a di-chloro-methane tris-olvate, C44H28Br4N4 (2+)·2ClO4 (-)·3CH2Cl2. The centrosymmetric neutral species is observed to have a mild 'ruffling' of the pyrrole rings and is essentially planar throughout; intra-molecular N-H⋯N hydrogen bonds occur. In contrast, the dication exhibits considerable deformation, with the pyrrole rings oriented well out of the plane of the porphyrin, resulting in a 'saddle' conformation of the ring. The charged species forms N-H⋯O hydrogen bonds to the perchlorate anions, which lie above and below the plane of the porphyrin ring. Distortions to the planarity of the pyrrole rings in both cases are very minor. The characterization of the neutral species represents a low-temperature redetermination of the previous room-temperature analyses [Zou et al. (1995 ▸). Acta Cryst. C51, 760-761; Rayati et al. (2008 ▸). Polyhedron, pp. 2285-2290], which showed disorder and physically unrealistic displacement parameters. PMID:27308051

  7. Bis(. eta. sup 5 -tricyclo(5. 2. 1. 0 sup 2,6 )deca-2,5,8-trien-4-yl) derivatives of the group IV transition metals

    SciTech Connect

    Bhide, V.V.; Rinaldi, P.L.; Farona, M.F. )

    1990-01-01

    Metallocene dichloride derivatives of titanium, zirconium, and hafnium were prepared from tricyclo(5.2.1.0{sup 2,6})deca-2,5,8-triene and the corresponding metal tetrachlorides. These compounds were characterized as existing primarily in the endo,endo and exo,endo forms by two-dimensional {sup 1}H NMR studies. These results were unexpected, in that theory predicts primarily exo,exo isomers should be preferred. A study on bis(isodicyclopentadienyl)titanium dichloride revealed the compound to exist in two major isomeric forms: exo,endo and exo,exo.

  8. 3,8-Dimethyl-4,7-diaza-deca-3,7-diene-2,9-dione dioxime.

    PubMed

    Achiwawanich, Supakit; Duangtongyou, Tanwawan; Pakawatchai, Chaveng; Siripaisarnpipat, Sutatip

    2010-01-01

    The complete mol-ecule of the title compound, C(10)H(18)N(4)O(2), is generated by a crystallographic inversion centre at the mid-point of the central C-C bond. The two oxime groups have an E configuration. In the crystal, mol-ecules are linked through inter-molecular O-H⋯N hydrogen bonds. PMID:21522645

  9. Synthesis of magnetically recyclable ZIF-8@SiO{sub 2}@Fe{sub 3}O{sub 4} catalysts and their catalytic performance for Knoevenagel reaction

    SciTech Connect

    Li, Qingyuan; Jiang, Sai; Ji, Shengfu Ammar, Muhammad; Zhang, Qingmin; Yan, Junlei

    2015-03-15

    Novel magnetic ZIF-8@SiO{sub 2}@Fe{sub 3}O{sub 4} catalysts were synthesized by encapsulating magnetic SiO{sub 2}@Fe{sub 3}O{sub 4} nanoparticles into ZIF-8 through in situ method. The structures of the catalysts were characterized by TEM, SEM, XRD, FT-IR, VSM, N{sub 2} adsorption/desorption and CO{sub 2}-TPD technology. The catalytic activity and recovery properties of the catalysts for the Knoevenagel reaction of p-chlorobenzaldehyde with malononitrile were evaluated. The results showed that the magnetic ZIF-8@SiO{sub 2}@Fe{sub 3}O{sub 4} catalysts had the larger surface areas, the suitable superparamagnetism, and good catalytic activity for Knoevenagel reaction. The conversion of p-chlorobenzaldehyde can reach ~98% and the selectivity of the production can reach ~99% over35.8%ZIF-8@SiO{sub 2}@Fe{sub 3}O{sub 4} (MZC-5) catalyst under the reaction condition of 25 °C and 4 h. The magnetic ZIF-8@SiO{sub 2}@Fe{sub 3}O{sub 4} catalysts also had good substrates adaptation. After reaction, the catalyst can be easily separated from the reaction mixture by an external magnet. The recovery catalyst can be reused five times and the conversion of p-chlorobenzaldehyde can be kept over 90%. - Graphical abstract: Novel magnetically recyclable ZIF-8@SiO{sub 2}@Fe{sub 3}O{sub 4} catalysts were synthesized by encapsulating magnetic SiO{sub 2}@Fe{sub 3}O{sub 4} nanoparticles into ZIF-8 and the as-synthesized catalysts exhibited a good catalytic activity for the Knoevenagel reaction. - Highlights: • A series of novel magnetic ZIF-8@SiO{sub 2}@Fe{sub 3}O{sub 4} catalysts were synthesized. • The catalysts had the larger surface areas and the suitable superparamagnetism. • The catalysts exhibited good catalytic activity for the Knoevenagel reaction. • After reaction the catalyst can be easily separated by an external magnet. • The recovery catalyst can be reused five times and can keep its catalytic activity.

  10. 41 CFR 51-8.4 - Availability of materials.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... 51-8.4 Section 51-8.4 Public Contracts and Property Management Other Provisions Relating to Public Contracts COMMITTEE FOR PURCHASE FROM PEOPLE WHO ARE BLIND OR SEVERELY DISABLED 8-PUBLIC AVAILABILITY OF AGENCY MATERIALS § 51-8.4 Availability of materials. Material described in 5 U.S.C. 552(a)(2) shall...

  11. Polarization Transfer in the 4He(e,e'p)3H Reaction at Q^2 = 0.8 and 1.3 (GeV/c)^2

    DOE PAGESBeta

    Michael Paolone; Malace, Simona P.; Strauch, Steffen

    2010-08-01

    Proton recoil polarization was measured in the quasielastic 4He(e,e'p)3H reaction at Q^2 = 0.8 (GeV/c)^2 and 1.3 (GeV/c)^2 with unprecedented precision. The polarization-transfer coefficients are found to differ from those of the 1H(e,e' p) reaction, contradicting a relativistic distorted-wave approximation, and favoring either the inclusion of medium-modified proton form factors predicted by the quark-meson coupling model or a spin-dependent charge-exchange final-state interaction. For the first time, the polarization-transfer ratio is studied as a function of the virtuality of the proton.

  12. Size dependent magnetic and magneto-optical properties of Ni0.2Zn0.8Fe2O4 nanoparticles

    NASA Astrophysics Data System (ADS)

    Li, Oksana A.; Lin, Chun-Rong; Chen, Hung-Yi; Hsu, Hua-Shu; Shih, Kun-Yauh; Edelman, Irina S.; Wu, Kai-Wun; Tseng, Yaw-Teng; Ovchinnikov, Sergey G.; Lee, Jiann-Shing

    2016-06-01

    Ni0.2Zn0.8Fe2O4 spinel nanoparticles have been synthesized by combustion method. Average particles size varies from 15.5 to 50.0 nm depending on annealing temperature. Correlations between particles size and magnetic and magneto-optical properties are investigated. Magnetization dependences on temperature and external magnetic field correspond to the sum of paramagnetic and superparamagnetic response. Critical size of single-domain transition is found to be 15.9 nm. Magnetic circular dichroism (MCD) studies of nickel zinc spinel are presented here for the first time. The features in magnetic circular dichroism spectrum are assigned to the one-ion d-d transitions in Fe3+ and Ni2+ ions, as well to the intersublattice and intervalence charge transfer transitions. The MCD spectrum rearrangement was revealed with the change of the nanoparticles size.

  13. Polarization transfer in the 4He(e→,e'p→)3H reaction at Q2 = 0.8 and 1.3 (GeV/c)2

    DOE PAGESBeta

    Michael Paolone; Malace, Simona P.

    2010-08-12

    Here, proton recoil polarization was measured in the quasielastic 4He(e→,e'p→)3H reaction at Q2 = 0.8 (GeV/c)2 and 1.3 (GeV/c)2 with unprecedented precision. The polarization-transfer coefficients are found to differ from those of the 1H(e→,e'p→) reaction, contradicting a relativistic distorted-wave approximation, and favoring either the inclusion of medium-modified proton form factors predicted by the quark-meson coupling model or a spin-dependent charge-exchange final-state interaction. For the first time, the polarization-transfer ratio is studied as a function of the virtuality of the proton.

  14. Electrical and optical properties of thermally-evaporated thin films from A2[TiO(C2O4)2] (A = K, PPh4) and 1,8-dihydroxyanthraquinone

    NASA Astrophysics Data System (ADS)

    Carbia-Ruelas, E.; Sánchez-Vergara, M. E.; García-Montalvo, V.; Morales-Saavedra, O. G.; Álvarez-Bada, J. R.

    2011-02-01

    In this work, the synthesis of molecular materials formed from A2[TiO(C2O4)2] (A = K, PPh4) and 1,8 dihydroxyanthraquinone is reported. The synthesized materials were characterized by atomic force microscopy (AFM), infrared (IR) and ultraviolet-visible (UV-vis) spectroscopy. IR spectroscopy showed that the molecular-material thin-films, deposited by vacuum thermal evaporation, exhibit the same intra-molecular vibration modes as the starting powders, which suggests that the thermal evaporation process does not alter the initial chemical structures. Electrical transport properties were studied by dc conductivity measurements. The electrical activation energies of the complexes, which were in the range of 0.003-1.16 eV, were calculated from Arrhenius plots. Optical absorption studies in the wavelength range of 190-1090 nm at room temperature showed that the optical band gaps of the thin films were around 1.9-2.3 eV for direct transitions Egd. The cubic NLO effects were substantially enhanced for materials synthesized from K2[TiO(C2O4)2], where χ(3) (-3ω; ω, ω, ω) values in the promising range of 10-12 esu have been evaluated.

  15. Perrierite-(La), (La,Ce,Ca)4(Fe2+,Mn)(Ti,Fe3+,Al)4(Si2O7)2O8, a new mineral species from the Eifel volcanic district, Germany

    NASA Astrophysics Data System (ADS)

    Chukanov, N. V.; Blass, G.; Pekov, I. V.; Belakovskiy, D. I.; Van, K. V.; Rastsvetaeva, R. K.; Aksenov, S. M.

    2012-12-01

    Non-metamict perrierite-(La) discovered in the Dellen pumice quarry, near Mendig, in the Eifel volcanic district, Rheinland-Pfalz, Germany has been approved as a new mineral species (IMA no. 2010-089). The mineral was found in the late assemblage of sanidine, phlogopite, pyrophanite, zirconolite, members of the jacobsite-magnetite series, fluorcalciopyrochlore, and zircon. Perrierite-(La) occurs as isolated prismatic crystals up to 0.5 × 1 mm in size within cavities in sanidinite. The new mineral is black with brown streak; it is brittle, with the Mohs hardness of 6 and distinct cleavage parallel to (001). The calculated density is 4.791 g/cm3. The IR spectrum does not contain absorption bands that correspond to H2O and OH groups. Perrierite-(La) is biaxial (-), α = 1.94(1), β = 2.020(15), γ = 2.040(15), 2 V meas = 50(10)°, 2 V calc = 51°. The chemical composition (electron microprobe, average of seven point analyses, the Fe2+/Fe3+ ratio determined from the X-ray structural data, wt %) is as follows: 3.26 CaO, 22.92 La2O3, 19.64 Ce2O3, 0.83 Pr2O2, 2.09 Nd2O3, 0.25 MgO, 2.25 MnO, 3.16 FeO, 5.28 Fe2O3, 2.59 Al2O3, 16.13 TiO2, 0.75 Nb2O5, and 20.06 SiO2, total is 99.21. The empirical formula is (La1.70Ce1.45Nd0.15Pr0.06Ca0.70)Σ4.06(Fe{0.53/2+}Mn0.38Mg0.08)Σ0.99(Ti2.44Fe{0.80/3+}Al0.62Nb0.07)Σ3.93Si4.04O22. The simplified formula is (La,Ce,Ca)4(Fe2+,Mn)(Ti,Fe3+,Al)4(Si2O7)2O8. The crystal structure was determined by a single crystal. Perrierite-(La) is monoclinic, space group P21/ a, and the unit-cell dimensions are as follows: a =13.668(1), b = 5.6601(6), c = 11.743(1) Å, β = 113.64(1)°; V = 832.2(2) Å3, Z = 2. The strong reflections in the X-ray powder diffraction pattern are [ d, Å ( I, %) ( hkl)]: 5.19 (40) (110), 3.53 (40) (overline 3 11), 2.96 (100) (overline 3 13, 311), 2.80 (50) (020), 2.14 (50) (overline 4 22, overline 3 15, 313), 1.947 (50) (024, 223), 1.657 (40) (overline 4 07, overline 4 33, 331). The holotype specimen of perrierite-(La) is

  16. 11 CFR 8.4 - Contents.

    Code of Federal Regulations, 2011 CFR

    1998-01-01

    ... Privacy Act notice required at 11 CFR 8.6(c) shall be reprinted with the instructions for that state. (7... 11 Federal Elections 1 1998-01-01 1998-01-01 false Contents. 8.4 Section 8.4 NATIONAL VOTER REGISTRATION ACT (42 U.S.C. 1973gg-1 et seq.) National Mail Voter Registration Form § 8.4 Contents....

  17. Quantification of the carcinogens 2-amino-3,8-dimethyl- and 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine in food using a combined assay based on gas chromatography-negative ion mass spectrometry.

    PubMed

    Murray, S; Lynch, A M; Knize, M G; Gooderham, M J

    1993-07-01

    A gas chromatographic-mass spectrometric assay has been developed for the measurement of 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (DiMeIQx) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in food. Stable isotope-labelled analogues of MeIQx and PhIP are used as internal standards and the synthesis of deuterated PhIP is described. The mass spectrometer is operated in the electron-capture negative ion chemical ionisation mode and the amines are chromatographed as their di-3,5-bistrifluoromethylbenzyl derivatives. All three compounds can be measured in a single chromatographic run and detection limits of 0.05, 0.1 and 0.2 ng/g for MeIQx, DiMeIQx and PhIP, respectively, in food are obtained. Various home-cooked and commercially prepared foodstuffs were analysed with this assay and several were found to contain measurable amounts of one or more of the three amines. These results are presented and discussed. PMID:8376502

  18. 3-Benzyl-8-meth­oxy-2-sulfanyl­idene-1,2,3,4-tetra­hydro­quinazolin-4-one

    PubMed Central

    Al-Salahi, Rashad; Al-Omar, Mohamed; Marzouk, Mohamed; Ng, Seik Weng

    2012-01-01

    The tetra­hydro­quinazole fused-ring system of the title compound, C16H14N2O2S, is roughly planar (r.m.s. deviation = 0.039 Å); the phenyl ring of the benzyl substituent is aligned at 78.1 (1)° with respect to the mean plane of the fused-ring system. In the crystal, two mol­ecules are linked by a pair of N—H⋯S hydrogen bonds about a center of inversion, generating a dimer. PMID:22719579

  19. Density functional study of electronic, charge density, and chemical bonding properties of 9-methyl-3-Thiophen-2-YI-Thieno [3,2-e] [1, 2, 4] Thriazolo [4,3-c] pyrimidine-8-Carboxylic acid ethyl ester crystals

    NASA Astrophysics Data System (ADS)

    Reshak, A. H.; Kamarudin, H.; Alahmed, Z. A.; Auluck, S.; Chyský, Jan

    2014-06-01

    A comprehensive theoretical density functional investigation of the electronic crystal structure, chemical bonding, and the electron charge densities of 9-Methyl-3-Thiophen-2-YI-Thieno [3, 2-e] [1, 2, 4] Thriazolo [4,3-c] Pyrimidine-8-Carboxylic Acid Ethyl Ester (C15H12N4O2S2) is performed. The density of states at Fermi level equal to 5.50 (3.45) states/Ry cell, and the calculated bare electronic specific heat coefficient is found to be 0.95 (0.59) mJ/mole-K2 for the local density approximation (Engel-Vosko generalized gradient approximation). The electronic charge density space distribution contours in (1 0 0) and (1 1 0) planes were calculated. We find that there are two independent molecules (A and B) in the asymmetric unit exhibit intramolecular C-H…O, C-H…N interactions. This intramolecular interaction is different in molecules A and B, where A molecule show C-H…O interaction while B molecule exhibit C-H…N interaction. We should emphasis that there is π-π interaction between the pyrimidine rings of the two neighbors B molecules gives extra strengths and stabilizations to the superamolecular structure. The calculated distance between the two neighbors pyrimidine rings found to be 3.345 Å, in good agreement with the measured one (3.424(1) Å).

  20. Extended analysis of the high resolution spectrum of C2H6 near 7 μm: the ν6, ν8, ν4 + ν12, 2ν4 + ν9 vibrational system, and associated hot transitions

    NASA Astrophysics Data System (ADS)

    Lattanzi, F.; di Lauro, C.; Vander Auwera, J.

    2011-09-01

    The room temperature high resolution infrared spectrum of C2H6 between 1330 and 1610 cm-1, the region of the ν6 and ν8 fundamentals, has been re-investigated owing to the relevance of this spectral region in atmospheric and planetary applied research. The assignments of transitions from the ground vibrational state to the upper states ν6, ν8, ν4 + ν12 and 2ν4 + ν9 (4592 in total) and from the lower state ν4 to the upper state ν4 + ν8 (1090 lines) have been considerably extended with respect to our previous work [F. Lattanzi, C. di Lauro and J. Vander Auwera, J. Mol. Spectrosc. 248 (2008) 134-145], especially for the hot transitions. In particular, three new series of perturbation activated transitions were found, with ΔK = ±2, made observable by the resonance of the type l(Δl = ±2, ΔK = ∓1) within ν8. Also, new P-transitions to ν6 were found, made observable by the x,y-Coriolis resonance with ν8, at the values of K from 15 to 18. The extension of the assignments in the high frequency wing of ν8 and their analysis allowed the discovery of two additional resonance interactions. The first interaction, a higher order Coriolis-type between ν8(±K, l = ±1) and ν6(±K ± 2, l = 0), induces a few detectable transitions to ν6 with ΔK = 3. The second interaction, of the type l(Δl = ±2, ΔK = ∓1), comes to resonance between ν8(k = ±19, l = ±1) and 2ν4 + ν9 (k = ±20, l = ∓1). This last resonance and the x,y-Coriolis resonance of ν6 and 2ν4 + ν9 allows one to observe several transitions to the 2ν4 + ν9 vibrational state. The extension of the assignments in the (ν4 + ν8) - ν4 hot band allowed discovery of a resonance interaction of the type l(Δl = ±2, ΔK = ∓1) between the states ν4 + ν8 and 2ν4 + ν12, in addition to their well known Fermi-type interaction. The K-values before and after the level crossing could be determined for both interactions. Better values were also determined for the J-structure parameters B, DJ and

  1. Role of C{sub 2}F{sub 4}, CF{sub 2}, and ions in C{sub 4}F{sub 8}/Ar plasma discharges under active oxide etch conditions in an inductively coupled GEC cell reactor

    SciTech Connect

    Barela, Marcos J.; Anderson, Harold M.; Oehrlein, Gottlieb S.

    2005-05-01

    Utilizing infrared diode-laser absorption spectroscopy (IRDLAS) and UV-Visible absorption spectroscopy (UV-Vis), we show that it is possible to make a near complete mass balance of etch reactants and products in a GEC inductively coupled fluorocarbon discharge while actively etching SiO{sub 2} substrates. Langmuir probe measurements were performed to measure the total ion current density. C{sub 2}F{sub 4} and CF{sub 2} are shown to be the main dissociation products in a C{sub 4}F{sub 8} plasma discharge. The C{sub 2}F{sub 4} concentration decreases as the SiO{sub 2} etching rate increases, along with CF{sub 2} and CF radicals, suggesting a role in the SiO{sub 2} etching process. The addition of Ar to the C{sub 4}F{sub 8} discharge increased the ion flux at the wafer surface, and the consumption rate of C{sub 2}F{sub 4} relative to CF{sub 2}. The increased ion flux enhanced the SiO{sub 2} etching rate, until at a very high degree of Ar dilution of C{sub 4}F{sub 8}/Ar the etching rate became neutral limited. We also monitored SiF{sub 2} using UV-Vis absorption and CO by IRDLAS. In our work we found SiF{sub 2} and CO to be the prevalent Si and C gas phase etch products for the SiO{sub 2} etching process.

  2. Selective synthesis of the [Ni36Co8C8(CO)48]6- octa-carbide carbonyl cluster by thermal decomposition of the [H2Ni22Co6C6(CO)36]4- hexa-carbide.

    PubMed

    Ciabatti, Iacopo; Fabrizi de Biani, Fabrizia; Femoni, Cristina; Iapalucci, Maria Carmela; Longoni, Giuliano; Zacchini, Stefano

    2013-07-14

    The thermal decomposition in thf solution of [H2Ni22Co6C6(CO)36](4-) results in the new [HNi36Co8C8(CO)48](5-) bimetallic Ni-Co octa-carbide, which can be converted into the closely related [H6-nNi36Co8C8(CO)48](n-) (n = 3-6) polyhydrides by means of acid-base reactions. The structure of the [Ni36Co8C8(CO)48](6-) hexa-anion has been established via X-ray crystallography, showing that the eight interstitial carbide atoms are lodged within different metal cages. Thus, two C-atoms are enclosed within regular square anti-prismatic Ni8C cages, four within irregular Ni8C square anti-prismatic cages, and the last two within mono-capped trigonal prismatic Ni5Co2C cages. The structure of [Ni36Co8C8(CO)48](6-) is non-compact and closely related to [Ni32C6(CO)38](6-) and [HNi38C6(CO)44](5-). [Ni36Co8C8(CO)48](6-) approaches the nanosize regime and the whole molecular ion has a diameter (measured from the outer oxygen atoms) of ca. 1.61 nm. PMID:23676989

  3. Coordination polymer template synthesis of hierarchical MnCo2O4.5 and MnNi6O8 nanoparticles for electrochemical capacitors electrode

    NASA Astrophysics Data System (ADS)

    Wang, Kuaibing; Xu, Jiangyan; Lu, Aimin; Shi, Ying; Lin, Zixia

    2016-08-01

    Two types of ternary metal oxides, MnCo2O4.5 and MnNi6O8 nanoparticles have been separately synthesized through chemical transformation from the corresponding bimetallic coordination polymer particles precursor under high-heating conditions. Series of electrochemical measurements are performed to examine the MnCo2O4.5 and MnNi6O8 electrodes, and the result shows that MnCo2O4.5 structure, especially for Mn/Co-600, has much higher capacitance than that of MnNi6O8 nanoparticles, indicating MnCo2O4.5 electrode is more suitable for applying in neutral electrolyte system. The Mn/Co-600 electrode exhibits a specific capacitance of 158 F g-1 at 5 mV s-1, good rate capability of 53.8% with a 20 times current density increase, good cycle performance (92.9% capacitance retention after 1000 cycles) and high power density (a specific power of 5760 W kg-1 at 4.0 A g-1) with low charge transfer resistance value of 1.8 Ω.

  4. 3,8-Dimethyl-4,7-diaza­deca-3,7-diene-2,9-dione dioxime

    PubMed Central

    Achiwawanich, Supakit; Duangtongyou, Tanwawan; Pakawatchai, Chaveng; Siripaisarnpipat, Sutatip

    2011-01-01

    The complete mol­ecule of the title compound, C10H18N4O2, is generated by a crystallographic inversion centre at the mid-point of the central C—C bond. The two oxime groups have an E configuration. In the crystal, mol­ecules are linked through inter­molecular O—H⋯N hydrogen bonds. PMID:21522645

  5. Precise ro-vibrational analysis of molecular bands forbidden in absorption: The ν8 +ν10 band of 13C2H4

    NASA Astrophysics Data System (ADS)

    Ulenikov, O. N.; Gromova, O. V.; Bekhtereva, E. S.; Kashirina, N. V.; Maul, C.; Bauerecker, S.

    2015-10-01

    The high resolution spectra of the 13C2H4 molecule was recorded with a Bruker IFS 120 Fourier transform spectrometer and theoretically analyzed in the 1650 - 1800cm-1 region of the ν8 +ν10 band which is forbidden in absorption. About 1200 experimental transitions with the maximum values of quantum numbers Jmax. = 34 and Kamax. = 17 were assigned to the ν8 +ν10 band. On that basis the 516 high accuracy ro-vibrational energies of the (v8=v10=1) vibrational state, as well as energy levels with J ≤ 2 of the (v4 =v8 = 1) and (v7 =v8 = 1) vibrational states, were determined which then were used as input data in the weighted fit of spectroscopic parameters of the Hamiltonian (strong local resonance interactions of the ν8 +ν10 band with the bands ν48 and ν7 +ν8 have been taken into account). A set of 34 vibrational, rotational, centrifugal distortion, and resonance interaction parameters was obtained from the fit. These parameters reproduce positions of about 1200 experimentally recorded and assigned transitions with the rms error drms = 0.00018cm-1 (blended and very weak transitions are not taken into account in that case).

  6. DNA Sequence Modulates Geometrical Isomerism of the trans-8,9-Dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy Aflatoxin B1 Adduct

    PubMed Central

    2016-01-01

    Aflatoxin B1 (AFB1), a mycotoxin produced by Aspergillus flavus, is oxidized by cytochrome P450 enzymes to aflatoxin B1-8,9-epoxide, which alkylates DNA at N7-dG. Under basic conditions, this N7-dG adduct rearranges to yield the trans-8,9-dihydro-8-(2,6-diamino-4-oxo-3,4-dihydropyrimid-5-yl-formamido)-9-hydroxy aflatoxin B1 (AFB1–FAPY) adduct. The AFB1–FAPY adduct exhibits geometrical isomerism involving the formamide moiety. NMR analyses of duplex oligodeoxynucleotides containing the 5′-XA-3′, 5′-XC-3′, 5′-XT-3′, and 5′-XY-3′ sequences (X = AFB1–FAPY; Y = 7-deaza-dG) demonstrate that the equilibrium between E and Z isomers is controlled by major groove hydrogen bonding interactions. Structural analysis of the adduct in the 5′-XA-3′ sequence indicates the preference of the E isomer of the formamide group, attributed to formation of a hydrogen bond between the formyl oxygen and the N6 exocyclic amino group of the 3′-neighbor adenine. While the 5′-XA-3′ sequence exhibits the E isomer, the 5′-XC-3′ sequence exhibits a 7:3 E:Z ratio at equilibrium at 283 K. The E isomer is favored by a hydrogen bond between the formyl oxygen and the N4-dC exocyclic amino group of the 3′-neighbor cytosine. The 5′-XT-3′ and 5′-XY-3′ sequences cannot form such a hydrogen bond between the formyl oxygen and the 3′-neighbor T or Y, respectively, and in these sequence contexts the Z isomer is favored. Additional equilibria between α and β anomers and the potential to exhibit atropisomers about the C5–N5 bond do not depend upon sequence. In each of the four DNA sequences, the AFB1–FAPY adduct maintains the β deoxyribose configuration. Each of these four sequences feature the atropisomer of the AFB1 moiety that is intercalated above the 5′-face of the damaged guanine. This enforces the Ra axial conformation for the C5–N5 bond. PMID:25587868

  7. Elastic Properties of Double-Layered Manganite La1.2Sr1.8-xBaxMn2O7 (x=0.0-0.4)

    NASA Astrophysics Data System (ADS)

    Reddy, Y. S.; Prashanth Kumar, V.; Ramesh, S.; Venkanna, S.; Ramana Reddy, M. V.; Kistaiah, P.; Vishnuvardhan Reddy, C.

    2008-06-01

    The elastic behavior of the sol-gel prepared double-layered manganite system La1.2Sr1.8-xBaxMn2O7 (x = 0.0-0.4) was investigated at 300 K, employing ultrasonic pulse transmission technique at 1 MHz. The values of elastic moduli and acoustic Debye temperature (θD) were computed from longitudinal and shear velocities. The measured values were corrected to zero porosity using Hasselman and Fulrath's formula. The elastic constants of the samples, estimated using Modi's heterogeneous metal-mixture rule, were also reported. The variation of elastic moduli with Ba concentration was interpreted in terms of strength of interatomic bonding.

  8. Crystal structure of superparamagnetic Mg0.2Ca0.8Fe2O4 nanoparticles synthesized by sol-gel method

    NASA Astrophysics Data System (ADS)

    Escamilla-Pérez, A. M.; Cortés-Hernández, D. A.; Almanza-Robles, J. M.; Mantovani, D.; Chevallier, P.

    2015-01-01

    Powders of magnetic iron oxide nanoparticles (Mg0.2Ca0.8Fe2O4) were prepared by a sol-gel method using ethylene glycol and nitrates of Fe, Ca and Mg as starting materials. Those powders were heat treated at different temperatures (573, 673, 773 and 873 K). In order to evaluate the effect of the heat treatment temperature on the nanoferrites properties, X-ray diffraction (XRD), vibrating sample magnetometry (VSM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) techniques were used. It was found that the reaction products exhibit nanometric sizes and superparamagnetic behavior. It is also demonstrated that, as the heat treatment temperature increases, the particle size and the saturation magnetization of the nanoferrites are increased.

  9. Corner sharing tetrahedral network in Co(3)(HAT)[N(CN)(2)](6)(OH(2))(2) (HAT = 1,4,5,8,9,12-hexaazatriphenylene).

    PubMed

    Marshall, Shireen R; Rheingold, Arnold L; Dawe, Louise N; Shum, William W; Kitamura, Chitoshi; Miller, Joel S

    2002-07-15

    We report a trinuclear Co(II) complex containing bridging dicyanamides and a tris-chelated HAT, which possesses approximately 37% void space. The magnetic exchange pathways appear in the structure as a corner sharing tetrahedral network. The compound crystallizes in the monoclinic space group P2(1)/c [a = 13.655(3) A, b = 15.189(3) A, c = 22.367(4) A, beta = 114.100(2) degrees, V = 4234.5(14) A(3), Z = 4, R(F(o)) = 0.0823]. The magnetic data were fit to an S = 3/2 model for systems dominated by zero-field splitting effects with g = 2.01 and D = 38.9 cm(-1). PMID:12099860

  10. Syntheses, crystal structures and optical spectroscopy of Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O

    SciTech Connect

    Kazmierczak, Karolina; Hoeppe, Henning A.

    2011-05-15

    The lanthanide sulphate octahydrates Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) and the respective tetrahydrate Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O were obtained by evaporation of aqueous reaction mixtures of trivalent rare earth oxides and sulphuric acid at 300 K. Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) crystallise in space group C2/c (Z=4, a{sub Ho}=13.4421(4) A, b{sub Ho}=6.6745(2) A, c{sub Ho}=18.1642(5) A, {beta}{sub Ho}=102.006(1) A{sup 3} and a{sub Tm}=13.4118(14) A, b{sub Tm}=6.6402(6) A, c{sub Tm}=18.1040(16) A, {beta}{sub Tm}=101.980(8) A{sup 3}), Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O adopts space group P2{sub 1}/n (a=13.051(3) A, b=7.2047(14) A, c=13.316(3) A, {beta}=92.55(3) A{sup 3}). The vibrational and optical spectra of Ho{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O are also reported. -- Graphical abstract: In the lanthanide sulphate octahydrates the cations form slightly undulated layers. Between the layers are voids in which sulphate tetrahedra and water molecules are located. The holmium compound exhibits an Alexandrite effect. Display Omitted Highlights: {yields} Determination of the optimum conditions for the growth of single-crystals of Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O. {yields} Single-crystal structure elucidation of Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) including hydrogen bonds. {yields} Single-crystal structure determination of Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O including hydrogen bonds. {yields} UV-vis spectra of Ho{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O recorded and interpreted: Assignation of bands and clarification of the Alexandrite effect of the Ho compound. {yields} IR and Raman spectra of Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O recorded and interpreted.

  11. Measurement of CD8+ and CD4+ T Cell Frequencies Specific for EBV LMP1 and LMP2a Using mRNA-Transfected DCs.

    PubMed

    Sohn, Dae-Hee; Sohn, Hyun-Jung; Lee, Hyun-Joo; Lee, Seon-Duk; Kim, Sueon; Hyun, Seung-Joo; Cho, Hyun-Il; Cho, Seok-Goo; Lee, Suk-Kyeong; Kim, Tai-Gyu

    2015-01-01

    An EBV-specific cellular immune response is associated with the control of EBV-associated malignancies and lymphoproliferative diseases, some of which have been successfully treated by adoptive T cell therapy. Therefore, many methods have been used to measure EBV-specific cellular immune responses. Previous studies have mainly used autologous EBV-transformed B-lymphoblastoid cell lines (B-LCLs), recombinant viral vectors transfected or peptide pulsed dendritic cells (DCs) as stimulators of CD8(+) and CD4(+) T lymphocytes. In the present study, we used an interferon-γ (IFN-γ) enzyme-linked immunospot (ELISPOT) assay by using isolated CD8(+) and CD4(+) T cells stimulated with mRNA-transfected DCs. The frequency of latent membrane protein 1 (LMP1)-specific IFN-γ producing CD4(+) T cells was significantly higher than that of LMP2a. The frequency of IFN-γ producing CD4(+) T cells was significantly correlated with that of CD8(+) T cells in LMP1-specific immune responses (r = 0.7187, Pc < 0.0001). To determine whether there were changes in LMP1- or LMP2a-specific immune responses, subsequent peripheral blood mononuclear cells (PBMCs) samples were analyzed. Significant changes were observed in 5 of the 10 donors examined, and CD4(+) T cell responses showed more significant changes than CD8(+) T cell responses. CD8(+) and CD4(+) T cells from EBV-seropositive donors secreted only the Th1 cytokines IFN-γ, TNF-α, and IL-2, while Th2 (IL-4) and Th17 (IL-17a) cytokines were not detected. CD4(+) T cells secreted significantly higher cytokine levels than did CD8(+) T cells. Analysis of EBV-specific T cell responses using autologous DCs transfected with mRNA might provide a comprehensive tool for monitoring EBV infection and new insights into the pathogenesis of EBV-associated diseases. PMID:26023769

  12. Discovery of 8-Cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x) as a Potent Inhibitor of Cyclin-Dependent Kinase 4 (CDK4) and AMPK-Related Kinase 5 (ARK5)

    PubMed Central

    2015-01-01

    The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, has created a great impetus for the development of additional kinase inhibitors as therapeutic agents. However, the complexity of cancer has led to recent interest in polypharmacological approaches for developing multikinase inhibitors with low toxicity profiles. With this goal in mind, we analyzed more than 150 novel cyano pyridopyrimidine compounds and identified structure–activity relationship trends that can be exploited in the design of potent kinase inhibitors. One compound, 8-cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x), was found to be the most active, inducing apoptosis of tumor cells at a concentration of approximately 30–100 nM. In vitro kinase profiling revealed that 7x is a multikinase inhibitor with potent inhibitory activity against the CDK4/CYCLIN D1 and ARK5 kinases. Here, we report the synthesis, structure–activity relationship, kinase inhibitory profile, in vitro cytotoxicity, and in vivo tumor regression studies by this lead compound. PMID:24417566

  13. 40 CFR 721.9850 - 2,4,8,10-Tetraoxa-3,9-diphosphaspiro[5.5]undecane, 3,9- bis[2,4,6-tris(1,1-dimethylethyl)phenoxy]-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 2,4,8,10-Tetraoxa-3,9-diphosphaspiro undecane, 3,9- bis -. 721.9850 Section 721.9850 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances...

  14. 40 CFR 721.9850 - 2,4,8,10-Tetraoxa-3,9-diphosphaspiro[5.5]undecane, 3,9- bis[2,4,6-tris(1,1-dimethylethyl)phenoxy]-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 2,4,8,10-Tetraoxa-3,9-diphosphaspiro undecane, 3,9- bis -. 721.9850 Section 721.9850 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances...

  15. 40 CFR 721.9850 - 2,4,8,10-Tetraoxa-3,9-diphosphaspiro[5.5]undecane, 3,9- bis[2,4,6-tris(1,1-dimethylethyl)phenoxy]-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 2,4,8,10-Tetraoxa-3,9-diphosphaspiro undecane, 3,9- bis -. 721.9850 Section 721.9850 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances...

  16. 40 CFR 721.9850 - 2,4,8,10-Tetraoxa-3,9-diphosphaspiro[5.5]undecane, 3,9- bis[2,4,6-tris(1,1-dimethylethyl)phenoxy]-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 2,4,8,10-Tetraoxa-3,9-diphosphaspiro undecane, 3,9- bis -. 721.9850 Section 721.9850 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances...

  17. 40 CFR 721.9850 - 2,4,8,10-Tetraoxa-3,9-diphosphaspiro[5.5]undecane, 3,9-bis[2,4,6-tris(1,1-dimethylethyl)phenoxy]-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 2,4,8,10-Tetraoxa-3,9-diphosphaspiro undecane, 3,9-bis -. 721.9850 Section 721.9850 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances...

  18. Dissociation of molecular chlorine in a Coulomb explosion: Potential curves, bound states, and deviation from Coulombic behavior for Cln+2 (n=2,3,4,6,8,10)

    NASA Astrophysics Data System (ADS)

    Wright, J. S.; Dilabio, G. A.; Matusek, D. R.; Corkum, P. B.; Ivanov, M. Yu.; Ellert, Ch.; Buenker, R. J.; Alekseyev, A. B.; Hirsch, G.

    1999-06-01

    Highly charged molecular ions are generated in Coulomb explosion experiments involving multielectron dissociative ionization, but little is known about the precise mechanisms involved in their formation. To help improve the understanding of such experiments, potential energy curves are calculated in this paper for diatomic chlorine (Cl2) and its ions Cln+2, where n=1,2,3,4,6,8,10. Bound vibrational states are obtained in three low-lying electronic states for Cl2+2 and one state for Cl3+2. Vertical excitation energies are given for stepwise excitations up to Cl10+2. For all the ions examined there is a significant energy defect (Δ) from the corresponding Coulomb potential, in one case reaching magnitudes of over 20 eV. We analyze the origin of these energy defects in terms of residual chemical bonding, and discuss the contribution of strongly bonding configurations at short internuclear distance. Finally, we present a simple physical model which describes the qualitative behavior of Δ(R,Q).

  19. Nature of magnetic interactions in 3D {[M(II)(pyrazole)4]2[Nb(IV)(CN)8].4H2O}n (M = Mn, Fe, Co, Ni) molecular magnets.

    PubMed

    Pinkowicz, Dawid; Pełka, Robert; Drath, Olga; Nitek, Wojciech; Bałanda, Maria; Majcher, Anna Małgorzata; Poneti, Giordano; Sieklucka, Barbara

    2010-08-16

    The self-assembly of [Nb(IV)(CN)(8)](4-) with different 3d metal centers in an aqueous solution and an excess of pyrazole resulted in the formation of four 3D isostructural compounds {[M(II)(pyrazole)(4)](2)[Nb(IV)(CN)(8)].4H(2)O}(n), where M(II) = Mn, Fe, Co, and Ni for 1-4, respectively. All four assemblies crystallize in the same I4(1)/a space group and show identical cyanido-bridged structures decorated with pyrazole molecules coordinated to M(II) centers. All four compounds show also long-range magnetic ordering below 24, 8, 6, and 13 K, respectively. A thorough analysis of the structural and magnetic data utilizing the molecular field model has allowed for an estimation of the values of coupling constants J(M-Nb) attributed to the one type of M(II)-NC-Nb(IV) linkage existing in 1-4. The J(M-Nb) values increase monotonically from -6.8 for 1 through -3.1 for 2 and +3.5 for 3, to +8.1 cm(-1) for 4 and are strongly correlated with the number of unpaired electrons on the M(II) metal center. Average orbital contributions to the total exchange coupling constants J(M-Nb) have also been identified and calculated: antiferromagnetic J(AF) = -21.6 cm(-1) originating from the d(xy), d(xz), and d(yz) orbitals of M(II) and ferromagnetic J(F) = +15.4 cm(-1) originating from d(z(2)) and d(x(2)-y(2)) orbitals of M(II). Antiferromagnetic interaction is successively weakened in the 1-4 row with each additional electron on the t(2g) level, which results in a change of the sign of J(M-Nb) and the nature of long-range magnetic ordering from ferrimagnetic in 1 and 2 to ferromagnetic in 3 and 4. PMID:20690767

  20. The Microwave Properties of Jovian Clouds: Laboratory Measurement of Aqueous Ammonia (NH4OH) Between 2-8.5 GHz

    NASA Astrophysics Data System (ADS)

    Duong, Danny; Steffes, P. G.

    2010-10-01

    Laboratory measurements of the complex dielectric properties of aqueous ammonia, under conditions characteristic of Jovian clouds, have been made in the 2-8.5 GHz range at temperatures ranging from 24-60 oC and concentrations of 0-8.5% ammonia (NH3) by volume. No previous laboratory experiments have been made to characterize the microwave dielectric properties of aqueous ammonia. Previous models of Jovian microwave emission (de Pater et al., Icarus, 2005) have assumed that for low concentrations of ammonia in solution, the dielectric properties of aqueous ammonia are approximately equal to those of water; however, these measurements suggest that even at concentrations as low as 0.5% NH3 by volume, there is a marked difference in the complex dielectric properties of aqueous ammonia. Assuming Raleigh scattering, these measurements are applied to a cloud attenuation model to calculate the opacity of the Jovian aqueous ammonia clouds. These measurements will improve our understanding of the data collected by the Juno microwave radiometer (MWR) by characterizing the absorption properties of the aqueous ammonia present in the Jovian atmosphere. This work was supported by NASA Contract NNM06AA75C from the Marshall Space Flight Center supporting the Juno Mission Science Team, under Subcontract 699054X from the South-west Research Institute.

  1. TiO2/vanadate (Sr10V6O25, Ni3V2O8, Zn2V2O7) heterostructured photocatalysts with enhanced photocatalytic activity for photoreduction of CO2 into CH4.

    PubMed

    Yan, Yabin; Yu, Yanlong; Wu, Di; Yang, Yajun; Cao, Yaan

    2016-01-14

    A series of TiO2/vanadate (Sr10V6O25, Ni3V2O8, Zn2V2O7) heterostructured photocatalysts were prepared by a simple sol-gel method. The theoretical calculations imply the possible energy band match between TiO2 and vanadates. Characterized by XRD, Raman, TEM, EDX, XPS, absorption spectra, PL and time-resolved PL decay curves, it is revealed that the vanadates, which exist on the surface of TiO2, could suppress the recombination of charge carriers, prolong the life-time of photogenerated electrons and provide surface reactive hole sites, improving the photocatalytic activity for photo-reduction of CO2 into CH4. PMID:26662343

  2. Current skin symptoms of Yusho patients exposed to high levels of 2,3,4,7,8-pentachlorinated dibenzofuran and polychlorinated biphenyls in 1968.

    PubMed

    Mitoma, Chikage; Mine, Yoshiko; Utani, Atsushi; Imafuku, Shinichi; Muto, Masahiko; Akimoto, Takamichi; Kanekura, Takuro; Furue, Masutaka; Uchi, Hiroshi

    2015-10-01

    Yusho was a mass food poisoning event due to the ingestion of rice oil contaminated with polychlorinated biphenyls (PCBs) and various dioxins and dioxin-like compounds. At its outbreak in 1968, Yusho patients suffered severe skin symptoms. Although the blood concentrations of PCBs and dioxins, especially highly toxic 2,3,4,7,8-pentachlorinated dibenzofuran (2,3,4,7,8-PeCDF) remain high in these patients, extensive analysis has not been performed on their current skin symptoms. We categorized and evaluated the specific skin symptoms in Yusho in 2012 by grading their severity using an arbitrary scoring system, and analyzed their correlations with the blood concentrations of 2,3,4,7,8-PeCDF and PCBs. A total of 352 Yusho patients underwent annual dermatological check-ups, in which five skin symptoms: black comedones, acneiform eruptions, scar formation, pigmentation and nail deformity, were evaluated for their distribution and severity. Approximately one-third of Yusho patients still presented with black comedones, acneiform eruptions and scar formation; the distributions of these symptoms were similar to those at the time of the Yusho outbreak. The mean blood concentrations of 2,3,4,7,8-PeCDF and total PCBs in Yusho patients were still higher than those in controls. The prevalence and severity of black comedones were correlated with age. Severity scores of black comedones and scar formation were positively correlated with 2,3,4,7,8-PeCDF blood level, and those of black comedones, scar formation, and pigmentation were positively correlated with total PCBs blood level. This study suggests that 2,3,4,7,8-PeCDF and PCBs remaining in Yusho patients still play crucial roles in the development of skin symptoms in Yusho. PMID:25985428

  3. 15 CFR 4.8 - Classified Information.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 1 2012-01-01 2012-01-01 false Classified Information. 4.8 Section 4... INFORMATION Freedom of Information Act § 4.8 Classified Information. In processing a request for information classified under Executive Order 12958 or any other executive order concerning the classification of...

  4. 15 CFR 4.8 - Classified Information.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 1 2013-01-01 2013-01-01 false Classified Information. 4.8 Section 4... INFORMATION Freedom of Information Act § 4.8 Classified Information. In processing a request for information classified under Executive Order 12958 or any other executive order concerning the classification of...

  5. 15 CFR 4.8 - Classified Information.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 1 2014-01-01 2014-01-01 false Classified Information. 4.8 Section 4... INFORMATION Freedom of Information Act § 4.8 Classified Information. In processing a request for information classified under Executive Order 12958 or any other executive order concerning the classification of...

  6. 15 CFR 4.8 - Classified Information.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Classified Information. 4.8 Section 4... INFORMATION Freedom of Information Act § 4.8 Classified Information. In processing a request for information classified under Executive Order 12958 or any other executive order concerning the classification of...

  7. 15 CFR 4.8 - Classified Information.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 1 2010-01-01 2010-01-01 false Classified Information. 4.8 Section 4... INFORMATION Freedom of Information Act § 4.8 Classified Information. In processing a request for information..., the information shall be reviewed to determine whether it should remain classified. Ordinarily...

  8. SYNTHESIS AND IDENTIFICATION OF 2,5-BIS-(4-HYDROXY-3-METHOXYPHENYL)-TETRAHYDROFURAN-3,4-DICARBOXYLIC ACID, AN UNANTICIPATED FERULATE 8-8-COUPLING PRODUCT ACYLATING CEREAL PLANT CELL WALLS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A new product implicated in cereal grain polysaccharide cross-linking has been authenticated by independent synthesis. Saponification of cereal grain fiber releases the RRRS/SSSR-isomer of 2,5-di-(4´-hydroxy-3´-methoxyphenyl)-2,3,4,5-tetrahydrofuran-3,4-dicarboxylic acid. The parent ester logically ...

  9. Polarization effects in molecular dynamics simulations of glass-formers Ca(NO3)2.nH2O, n=4, 6, and 8

    NASA Astrophysics Data System (ADS)

    Ribeiro, Mauro C. C.

    2010-04-01

    Thermodynamics, equilibrium structure, and dynamics of glass-forming liquids Ca(NO3)2ṡnH2O, n =4, 6, and 8, have been investigated by molecular dynamics (MD) simulations. A polarizable model was considered for H2O and NO3- on the basis of previous fluctuating charge models for pure water and the molten salt 2Ca(NO3)2ṡ3KNO3. Similar thermodynamic properties have been obtained with nonpolarizable and polarizable models. The glass transition temperature, Tg, estimated from MD simulations was dependent on polarization, in particular the dependence of Tg with electrolyte concentration. Significant polarization effects on equilibrium structure were observed in cation-cation, cation-anion, and water-water structures. Polarization increases the diffusion coefficient of H2O, but does not change significantly the diffusion coefficients of ions. Viscosity decreases upon inclusion of polarization, but the conductivity calculated with the polarizable model is smaller than the nonpolarizable model because polarization enhances anion-cation interactions.

  10. Elevated Expression of CD160 and 2B4 Defines a Cytolytic HIV-Specific CD8+ T-Cell Population in Elite Controllers.

    PubMed

    Pombo, Carolina; Wherry, E John; Gostick, Emma; Price, David A; Betts, Michael R

    2015-11-01

    During chronic human immunodeficiency virus (HIV) infection, virus-specific CD8(+) T cells become functionally exhausted. Unlike most chronically infected individuals, elite controllers of HIV retain CD8(+) T-cell polyfunctionality and cytolytic capacity. It remains unclear whether elite controllers manifest T-cell exhaustion similar to subjects with chronic progression of HIV infection. Here we assessed coexpression of PD-1, Lag-3, CD160, and 2B4 as a measure of T-cell exhaustion in a cohort of elite controllers and in chronic progressors. We found that elite controllers have a high proportion of potentially exhausted (PD1(+)CD160(+)2B4(+)) HIV-specific CD8(+) T cells that is comparable to the proportion in chronic progressors. However, elite controllers also harbor a population of HIV-specific CD160(+)2B4(+) CD8(+) T cells that correlates with cytolytic capacity, as measured by perforin expression, a population not commonly present in chronic progressors. We therefore propose that coexpression of CD160 and 2B4 delineates a population of cytolytic CD8(+) T cells important for the control of HIV. PMID:25883386

  11. Vigrishinite, Zn2Ti4 - x Si4O14(OH,H2O,□)8, a new mineral from the Lovozero alkaline complex, Kola Peninsula, Russia

    NASA Astrophysics Data System (ADS)

    Pekov, I. V.; Britvin, S. N.; Zubkova, N. V.; Chukanov, N. V.; Bryzgalov, I. A.; Lykova, I. S.; Belakovskiy, D. I.; Pushcharovsky, D. Yu.

    2013-12-01

    A new mineral vigrishinite, epistolite-group member and first layer titanosilicate with species-defining Zn, was found at Mt. Malyi Punkaruaiv, in the Lovozero alkaline complex, Kola Peninsula, Russia. It occurs in a hydrothermally altered peralkaline pegmatite and is associated with microcline, ussingite, aegirine, analcime, gmelinite-Na, and chabazite-Ca. Vigrishinite forms rectangular or irregularly shaped lamellae up to 0.05 × 2 × 3 cm flattened on [001]. They are typically slightly split and show blocky character. The mineral is translucent to transparent and pale pink, yellowish-pinkish or colorless. The luster is vitreous. The Mohs' hardness is 2.5-3. Vigrishinite is brittle. Cleavage is {001} perfect. D meas = 3.03(2), D calc = 2.97 g/cm3. The mineral is optically biaxial (-), α = 1.755(5), β = 1.82(1), γ = 1.835(8), 2 V meas = 45(10)°, 2 V calc = 50°. IR spectrum is given. The chemical composition (wt %; average of 9 point analyses, H2O is determined by modified Penfield method) is as follows: 0.98 Na2O, 0.30 K2O, 0.56 CaO, 0.05 SrO, 0.44 BaO, 0.36 MgO, 2.09 MnO, 14.39 ZnO, 2.00 Fe2O3, 0.36 Al2O3, 32.29 SiO2, 29.14 TiO2, 2.08 ZrO2, 7.34 Nb2O5, 0.46 F, 9.1 H2O, -0.19 O=F2, total is 101.75. The empirical formula calculated on the basis of Si + Al = 4 is: H7.42(Zn1.30Na0.23Mn0.22Ca0.07Mg0.07K0.05Ba0.02)Σ1.96(Ti2.68Nb0.41Fe{0.18/3+}Zr0.12)Σ3.39(Si3.95Al0.05)Σ4 20.31F0.18. The simplified formula is: Zn2Ti4- x Si4O14(OH,H2O,□)8 ( x < 1). Vigrishinite is triclinic, space group P , a = 8.743(9), b = 8.698(9), c = 11.581(11)Å, α = 91.54(8)°, β = 98.29(8)°, γ = 105.65(8)°, V = 837.2(1.5) Å3, Z = 2. The strongest reflections in the X-ray powder pattern ( d, Å, - I[ hkl]) are: 11.7-67[001], 8.27-50[100], 6.94-43[01, 10], 5.73-54[11, 002], 4.17-65[020, 2, 200], and 2.861-100[30, 22, 004, 11]. The crystal structure model was obtained on a single crystal, R = 0.171. Vigrishinite and murmanite are close in the structure of the TiSiO motif, but

  12. Mössbauer studies on cation distributions and superexchange interactions in Cu0.2Fe2.8O4

    NASA Astrophysics Data System (ADS)

    Kim, Sam Jin; Choi, Hyunkyung; Lim, Jung Tae; Kim, Chul Sung; Hahn, Eun Joo

    2016-02-01

    The cation distributions and the superexchange interactions of Cu0.2Fe2.8O4 have been studied by Mössbauer spectroscopy and X-ray diffraction. The crystal is found to have a cubic spinel structure with the lattice constant a 0 = 8.4007 ± 0.0004 ˚A. The Mössbauer spectra show line broadening in the octahedral ( B) site, which is interpreted by probability distribution of cations. The dominant superexchange interaction is found to be an antiferromagnetic intersublattice A- O- B superexchange interaction, and its strength is J A- B = -20.7 k B . The intrasublattice A- O- A superexchange interaction is also antiferromagnetic and its strength is J A- A = -9.3 k B . The weakest superexchange interaction is the ferromagnetic B-O-B interaction: J B- B = 0.7 k B . The Debye temperatures of the tetrahedral and the octahedral sites are found to be Θ A = 459 ± 5 K and Θ B = 351 ± 5 K, respectively.

  13. 8-Chloro-5-(4-phenethylpiperazin-1-­yl)pyrido[2,3-b][1,5]benzoxazepine

    PubMed Central

    Capuano, Ben; Crosby, Ian T.; Forsyth, Craig M.; Lloyd, Edward J.; Vom, Amelia; Yuriev, Elizabeth

    2008-01-01

    As part of an anti­psychotic drug discovery program, we report the crystal structure of the title compound, C24H23ClN4O. The mol­ecule has a tricyclic framework with a characteristic buckled V-shaped pyridobenzoxazepine unit, with the central seven-membered heterocycle in a boat configuration. The piperazine ring displays a chair conformation with the 2-phenyl-ethyl substituent assuming an equatorial orientation. There are two crystallographically independent, but virtually identical, mol­ecules in the asymmetric unit. PMID:21201082

  14. Synthesis and structure of a heterometallic cluster with a novel layered structure: (W(CO)/sub 5/SnClFe(CO)/sub 4/)/sub 2/(Na/sub 2/((C/sub 2/H/sub 5/)/sub 2/O)/sub 4/(C/sub 4/H/sub 8/O/sub 2/))

    SciTech Connect

    Balch, A.L.; Olmstead, M.M.; Oram, D.P.

    1988-11-16

    In an attempt to create an example of substituent-free complex derived from Sn(II), the reaction between (OC)/sub 5/WSnCl/sub 2/(tetrahydrofuran) and Fe(CO)/sub 4//sup /minus/2/ was studied. Instead of the expected compound (OC)/sub 5/WSn=Fe(CO)/sub 4/, the dimer (W(CO)/sub 5/SnClFe(CO)/sub 4/)/sub 2/Na/sub 2/(C/sub 2/H/sub 5/)O/sub 4/(C/sub 4/H/sub 8/O/sub 2/) was the product formed. The properties and structure of this dimer are reported herein. 17 refs., 3 figs., 3 tabs.

  15. Ba4Ru3O10.2(OH)1.8: a new member of the layered hexagonal perovskite family crystallised from water.

    PubMed

    Hiley, Craig I; Lees, Martin R; Hammond, David L; Kashtiban, Reza J; Sloan, Jeremy; Smith, Ronald I; Walton, Richard I

    2016-05-11

    A new barium ruthenium oxyhydroxide Ba4Ru3O10.2(OH)1.8 crystallises under hydrothermal conditions at 200 °C: powder neutron diffraction data show it adopts an 8H hexagonal perovskite structure with a new stacking sequence, while high resolution electron microscopy reveals regions of ordered layers of vacant Ru sites, and magnetometry shows antiferromagnetism with TN = 200(5) K. PMID:27074292

  16. Synthesis and SAR studies of novel 6,7,8-substituted 4-substituted benzyloxyquinolin-2(1H)-one derivatives for anticancer activity

    PubMed Central

    Chen, Yi-Fong; Lin, Yi-Chien; Morris-Natschke, Susan L; Wei, Chen-Fang; Shen, Ting-Chen; Lin, Hui-Yi; Hsu, Mei-Hua; Chou, Li-Chen; Zhao, Yu; Kuo, Sheng-Chu; Lee, Kuo-Hsiung; Huang, Li-Jiau

    2015-01-01

    Background and Purpose 4-Phenylquinolin-2(1H)-one (4-PQ) derivatives can induce cancer cell apoptosis. Additional new 4-PQ analogs were investigated as more effective, less toxic antitumour agents. Experimental Approach Forty-five 6,7,8-substituted 4-substituted benzyloxyquinolin-2(1H)-one derivatives were synthesized. Antiproliferative activities were evaluated using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliun bromide assay and structure–activity relationship correlations were established. Compounds 9b, 9c, 9e and 11e were also evaluated against the National Cancer Institute-60 human cancer cell line panel. Hoechst 33258 and Annexin V-FITC/PI staining assays were used to detect apoptosis, while inhibition of microtubule polymerization was assayed by fluorescence microscopy. Effects on the cell cycle were assessed by flow cytometry and on apoptosis-related proteins (active caspase-3, -8 and -9, procaspase-3, -8, -9, PARP, Bid, Bcl-xL and Bcl-2) by Western blotting. Key Results Nine 6,7,8-substituted 4-substituted benzyloxyquinolin-2(1H)-one derivatives (7e, 8e, 9b, 9c, 9e, 10c, 10e, 11c and 11e) displayed high potency against HL-60, Hep3B, H460, and COLO 205 cancer cells (IC50 < 1 μM) without affecting Detroit 551 normal human cells (IC50 > 50 μM). Particularly, compound 11e exhibited nanomolar potency against COLO 205 cancer cells. Mechanistic studies indicated that compound 11e disrupted microtubule assembly and induced G2/M arrest, polyploidy and apoptosis via the intrinsic and extrinsic signalling pathways. Activation of JNK could play a role in TRAIL-induced COLO 205 apoptosis. Conclusion and Implications New quinolone derivatives were identified as potential pro-apoptotic agents. Compound 11e could be a promising lead compound for future antitumour agent development. PMID:25363404

  17. Ring-strain release in neutral and dicationic 7,8,17,18-tetra­bromo-5,10,15,20-tetra­phenyl­porphyrin: crystal structures of C44H26Br4N4 and C44H28Br4N4 22ClO4 −·3CH2Cl2

    PubMed Central

    Scheidt, W. Robert; Duval, Hugues F.; Oliver, Allen G.

    2016-01-01

    Two porphyrin complexes were studied to determine the effects of protonation on ring deformation within the porphyrin. The porphyrin 7,8,17,18-tetra­bromo-5,10,15,20-tetra­phenyl­porphyrin, C44H26Br4N4, was selected because the neutral species is readily doubly protonated to yield a dication, which was crystallized here with perchlorate counter-ions as a di­chloro­methane tris­olvate, C44H28Br4N4 22ClO4 −·3CH2Cl2. The centrosymmetric neutral species is observed to have a mild ‘ruffling’ of the pyrrole rings and is essentially planar throughout; intra­molecular N—H⋯N hydrogen bonds occur. In contrast, the dication exhibits considerable deformation, with the pyrrole rings oriented well out of the plane of the porphyrin, resulting in a ‘saddle’ conformation of the ring. The charged species forms N—H⋯O hydrogen bonds to the perchlorate anions, which lie above and below the plane of the porphyrin ring. Distortions to the planarity of the pyrrole rings in both cases are very minor. The characterization of the neutral species represents a low-temperature redetermination of the previous room-temperature analyses [Zou et al. (1995 ▸). Acta Cryst. C51, 760–761; Rayati et al. (2008 ▸). Polyhedron, pp. 2285–2290], which showed disorder and physically unrealistic displacement parameters. PMID:27308051

  18. Variation of the Side Chain Branch Position Leads to Vastly Improved Molecular Weight and OPV Performance in 4,8-dialkoxybenzo[1,2-b:4,5-b′]dithiophene/2,1,3-benzothiadiazole Copolymers

    DOE PAGESBeta

    Coffin, Robert C.; MacNeill, Christopher M.; Peterson, Eric D.; Ward, Jeremy W.; Owen, Jack W.; McLellan, Claire A.; Smith, Gregory M.; Noftle, Ronald E.; Jurchescu, Oana D.; Carroll, David L.

    2011-01-01

    Tmore » hrough manipulation of the solubilizing side chains, we were able to dramatically improve the molecular weight ( M w ) of 4,8-dialkoxybenzo[1,2- b :4,5- b ′ ]dithiophene (BDT)/2,1,3-benzothiadiazole (BT) copolymers. When dodecyl side chains ( P1 ) are employed at the 4- and 8-positions of the BDT unit, we obtain a chloroform-soluble copolymer fraction with M w of 6.3 kg/mol. Surprisingly, by moving to the commonly employed 2-ethylhexyl branch ( P2 ), M w decreases to 3.4 kg/mol.his is despite numerous reports that this side chain increases solubility and M w . By moving the ethyl branch in one position relative to the polymer backbone (1-ethylhexyl, P3 ), M w is dramatically increased to 68.8 kg/mol. As a result of this M w increase, the shape of the absorption profile is dramatically altered, with λ max = 637 nm compared with 598 nm for P1 and 579 nm for P2 .he hole mobility as determined by thin film transistor (TFT) measurements is improved from ~ 1 × 10 − 6  cm 2 /Vs for P1 and P2 to 7 × 10 − 4  cm 2 /Vs for P3 , while solar cell power conversion efficiency in increased to 2.91 % for P3 relative to 0.31 % and 0.19 % for P1 and P2 , respectively.« less

  19. 8-Substituted Pyrido[3,4-d]pyrimidin-4(3H)-one Derivatives As Potent, Cell Permeable, KDM4 (JMJD2) and KDM5 (JARID1) Histone Lysine Demethylase Inhibitors

    PubMed Central

    2016-01-01

    We report the discovery of N-substituted 4-(pyridin-2-yl)thiazole-2-amine derivatives and their subsequent optimization, guided by structure-based design, to give 8-(1H-pyrazol-3-yl)pyrido[3,4-d]pyrimidin-4(3H)-ones, a series of potent JmjC histone N-methyl lysine demethylase (KDM) inhibitors which bind to Fe(II) in the active site. Substitution from C4 of the pyrazole moiety allows access to the histone peptide substrate binding site; incorporation of a conformationally constrained 4-phenylpiperidine linker gives derivatives such as 54j and 54k which demonstrate equipotent activity versus the KDM4 (JMJD2) and KDM5 (JARID1) subfamily demethylases, selectivity over representative exemplars of the KDM2, KDM3, and KDM6 subfamilies, cellular permeability in the Caco-2 assay, and, for 54k, inhibition of H3K9Me3 and H3K4Me3 demethylation in a cell-based assay. PMID:26741168

  20. 8-Substituted Pyrido[3,4-d]pyrimidin-4(3H)-one Derivatives As Potent, Cell Permeable, KDM4 (JMJD2) and KDM5 (JARID1) Histone Lysine Demethylase Inhibitors.

    PubMed

    Bavetsias, Vassilios; Lanigan, Rachel M; Ruda, Gian Filippo; Atrash, Butrus; McLaughlin, Mark G; Tumber, Anthony; Mok, N Yi; Le Bihan, Yann-Vaï; Dempster, Sally; Boxall, Katherine J; Jeganathan, Fiona; Hatch, Stephanie B; Savitsky, Pavel; Velupillai, Srikannathasan; Krojer, Tobias; England, Katherine S; Sejberg, Jimmy; Thai, Ching; Donovan, Adam; Pal, Akos; Scozzafava, Giuseppe; Bennett, James M; Kawamura, Akane; Johansson, Catrine; Szykowska, Aleksandra; Gileadi, Carina; Burgess-Brown, Nicola A; von Delft, Frank; Oppermann, Udo; Walters, Zoe; Shipley, Janet; Raynaud, Florence I; Westaway, Susan M; Prinjha, Rab K; Fedorov, Oleg; Burke, Rosemary; Schofield, Christopher J; Westwood, Isaac M; Bountra, Chas; Müller, Susanne; van Montfort, Rob L M; Brennan, Paul E; Blagg, Julian

    2016-02-25

    We report the discovery of N-substituted 4-(pyridin-2-yl)thiazole-2-amine derivatives and their subsequent optimization, guided by structure-based design, to give 8-(1H-pyrazol-3-yl)pyrido[3,4-d]pyrimidin-4(3H)-ones, a series of potent JmjC histone N-methyl lysine demethylase (KDM) inhibitors which bind to Fe(II) in the active site. Substitution from C4 of the pyrazole moiety allows access to the histone peptide substrate binding site; incorporation of a conformationally constrained 4-phenylpiperidine linker gives derivatives such as 54j and 54k which demonstrate equipotent activity versus the KDM4 (JMJD2) and KDM5 (JARID1) subfamily demethylases, selectivity over representative exemplars of the KDM2, KDM3, and KDM6 subfamilies, cellular permeability in the Caco-2 assay, and, for 54k, inhibition of H3K9Me3 and H3K4Me3 demethylation in a cell-based assay. PMID:26741168

  1. Syntheses, structures, and optical properties of the indium/germanium selenides Cs{sub 4}In{sub 8}GeSe{sub 16}, CsInSe{sub 2}, and CsInGeSe{sub 4}

    SciTech Connect

    Ward, Matthew D.; Pozzi, Eric A.; Van Duyne, Richard P.; Ibers, James A.

    2014-04-01

    The three solid-state indium/germanium selenides Cs{sub 4}In{sub 8}GeSe{sub 16}, CsInSe{sub 2}, and CsInGeSe{sub 4} have been synthesized at 1173 K. The structure of Cs{sub 4}In{sub 8}GeSe{sub 16} is a three-dimensional framework whereas those of CsInSe{sub 2} and CsInGeSe{sub 4} comprise sheets separated by Cs cations. Both Cs{sub 4}In{sub 8}GeSe{sub 16} and CsInGeSe{sub 4} display In/Ge disorder. From optical absorption measurements these compounds have band gaps of 2.20 and 2.32 eV, respectively. All three compounds are charge balanced. - Graphical abstract: Structure of Cs{sub 4}In{sub 8}GeSe{sub 16}. - Highlights: • The solid-state In/Ge selenides Cs{sub 4}In{sub 8}GeSe{sub 16}, CsInSe{sub 2}, and CsInGeSe{sub 4} have been synthesized. • Both Cs{sub 4}In{sub 8}GeSe{sub 16} and CsInGeSe{sub 4} display In/Ge disorder. • Cs{sub 4}In{sub 8}GeSe{sub 16} and CsInGeSe{sub 4} have band gaps of 2.20 eV and 2.32 eV, respectively.

  2. Analysis of the insulation characteristics of c-C4F8 and N2 gas mixtures by Boltzmann equation method

    NASA Astrophysics Data System (ADS)

    Deng, Y. K.; Xiao, D. M.

    2012-02-01

    The present paper concerns itself with the insulation characteristics of c-C4F8/N2 gas mixtures and studies the possibility of applying in the gas insulation of power equipments. We aim to use the theoretical framework of the Boltzmann equation to calculate the density-normalized effective ionization coefficients (α-ƞ)/N and transport parameters of c-C4F8/N2 gas mixtures for E/N values from 180 to 550 Td (1 Td = 10-17 V cm2) in the condition of steady-state Townsend (SST) experiment. From the variation curve of (α-ƞ)/N with the c-C4F8 mixture ratio k, the limiting field strength (E/N)lim of the gas mixtures at different gas content is determined. In order to confirm the validity of the results obtained, comparisons with Monte Carlo simulation and experimental data have been performed. It is found that the insulation properties of c-C4F8 and N2 gas mixtures are much better than those of SF6 and N2 mixtures for applying in the high voltage apparatus as an insulation medium, especially if we take the global warming potential into account.

  3. Increase of dielectric constant in PVDF by incorporating La1.8Sr0.2NiO4 into its matrix

    NASA Astrophysics Data System (ADS)

    Kumar, Rajnish; Goswami, Ashwin M.; Kar, Manoranjan

    2016-05-01

    To obtain the material with high dielectric constant and high dielectric strength for the technological applications, nanocomposite of Lanthanum Strontium Nickelete (La1.8Sr0.2NiO4) as nanofiller and polyvinylidene fluoride (PVDF) as polymer matrix has been prepared. The different nanofiler weight concentration varies from 2-8 weight percent. X-ray diffraction technique confirms the phase formation of nanocomposite. Differential scanning calorimeter (DSC) has been employed to study the percentage of crystallinity and Impedance measurement has been carried out to study the dielectric constant. DSC analysis shows decreasing trend of crystallinity whereas impedance analysis gives increasing dielectric constant with increasing La1.8Sr0.2NiO4 concentration in the nanocomposite. Also, these materials can be used as insulator in the transformer as the strength and dielectric behavior of present composite meets the technological requirements.

  4. 2,3,4,7,8-Pentachlorodibenzofuran is far less potent than 2,3,7,8-tetrachlorodibenzo-p-dioxin in disrupting the pituitary–gonad axis of the rat fetus

    SciTech Connect

    Taura, Junki; Takeda, Tomoki; Fujii, Misaki; Hattori, Yukiko; Ishii, Yuji; Kuroki, Hiroaki; Tsukimori, Kiyomi; Uchi, Hiroshi; Furue, Masutaka; Yamada, Hideyuki

    2014-11-15

    The effect of 2,3,4,7,8-pentachlorodibenzofuran (PnCDF) on the fetal pituitary–gonad axis was compared with that produced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in Wistar rats. Maternal treatment at gestational day (GD) 15 with PnCDF and TCDD reduced the fetal expression at GD20 of pituitary luteinizing hormone (LH) and the testicular proteins necessary for steroidogenesis. The relative potencies of PnCDF ranged from 1/42nd to 1/63rd of the TCDD effect. While PnCDF, at a dose sufficient to cause a reduction in fetal LH, provoked defects in sexual behavior at adulthood, a dose less than the ED{sub 50} failed to produce any abnormality. There was a loss of fetal body weight following in utero exposure to PnCDF, and the effect of PnCDF was also much less than that of TCDD. The disturbance in fetal growth was suggested to be due to a reduction in the level of fetal growth hormone (GH) by dioxins. The disorder caused by PnCDF/TCDD in the fetal pituitary–gonad axis occurred at doses less than those needed to cause wasting syndrome in pubertal rats. The harmful effect of PnCDF relative to TCDD was more pronounced in fetal rats than in pubertal rats. These lines of evidence suggest that: 1) PnCDF as well as TCDD imprints defects in sexual behavior by disrupting the fetal pituitary–gonad axis; 2) these dioxins hinder fetal growth by reducing the expression of fetal GH; and 3) the fetal effects of PnCDF/TCDD are more sensitive than sub-acute toxicity during puberty, and the relative effect of PnCDF varies markedly depending on the indices used. - Highlights: • 2,3,4,7,8-Pentachlorodibenzofuran (PnCDF) lowers gonadal steroidogenesis in fetuses. • PnCDF exerts the above effect through an initial attenuation in gonadotropin level. • PnCDF imprints sexual immaturity by transiently disrupting the pituitary–gonad axis. • PnCDF also disturbs pup growth probably due to a reduction in growth hormone level. • The above effects are far lesser in PnCDF than 2,3,7,8

  5. Arachidonic Acid Pathway Members PLA2G7, HPGD, EPHX2, and CYP4F8 Identified as Putative Novel Therapeutic Targets in Prostate Cancer

    PubMed Central

    Vainio, Paula; Gupta, Santosh; Ketola, Kirsi; Mirtti, Tuomas; Mpindi, John-Patrick; Kohonen, Pekka; Fey, Vidal; Perälä, Merja; Smit, Frank; Verhaegh, Gerald; Schalken, Jack; Alanen, Kalle A.; Kallioniemi, Olli; Iljin, Kristiina

    2011-01-01

    The arachidonic acid and prostaglandin pathway has been implicated in prostate carcinogenesis, but comprehensive studies of the individual members in this key pathway are lacking. Here, we first conducted a systematic bioinformatic study of the expression of 36 arachidonic acid pathway genes across 9783 human tissue samples. The results showed that the PLA2G7, HPGD, EPHX2, and CYP4F8 genes are highly expressed in prostate cancer. Functional studies using RNA interference in prostate cancer cells indicated that all four genes are also essential for cell growth and survival. Clinical validation confirmed high PLA2G7 expression, especially in ERG oncogene-positive prostate cancers, and its silencing sensitized ERG-positive prostate cancer cells to oxidative stress. HPGD was highly expressed in androgen receptor (AR)-overexpressing advanced tumors, as well as in metastatic prostate cancers. EPHX2 mRNA correlated with AR in primary prostate cancers, and its inhibition in vitro reduced AR signaling and potentiated the effect of antiandrogen flutamide in cultured prostate cancer cells. In summary, we identified four novel putative therapeutic targets with biomarker potential for different subtypes of prostate cancer. In addition, our results indicate that inhibition of these enzymes may be particularly powerful when combined with other treatments, such as androgen deprivation or induction of oxidative stress. PMID:21281786

  6. Fabrication of high-resolution 4,8(2) -type archimedean nanolattices composed of solution processable spin cross-over Fe(II) metallosupramolecular polymers.

    PubMed

    Venkataramudu, Uppari; Chandrasekhar, Naisa; Basak, Supratim; Prasad, Muvva D; Chandrasekar, Rajadurai

    2015-04-01

    This paper presents the synthesis of two highly soluble Fe(II) metallosupramolecular polymers with two counter anions from a novel back-to-back coupled hybrid ligand. The spin cross-over (SCO) temperature of polymers with BF4 and ClO4 counter anions is T1/2 = 313 K and T1/2 = 326 K, respectively. By following the top-down approach, one of the polymers (with ClO4 counter anion) is successfully solution processed using a lithographically controlled wetting technique to create laser readable high-resolution Archimedean (4,8(2) ) nanolattices (consist of diamagnetic octagons and SCO squares). The thickness and top area of each SCO square are ≈75 nm and ≈2 × 2 μm(2) , respectively. PMID:25594848

  7. Mg{sub 8}Rh{sub 4}B - A new type of boron stabilized Ti{sub 2}Ni structure

    SciTech Connect

    Alekseeva, A.M. . E-mail: alekseev@cpfs.mpg.de; Abakumov, A.M.; Leithe-Jasper, A.; Schnelle, W.; Prots, Yu.; Chizhov, P.S.; Van Tendeloo, G.; Antipov, E.V.; Grin, Yu.

    2006-09-15

    The new magnesium rhodium boron compound Mg{sub 8}Rh{sub 4}B has been synthesized by reaction of the metal powders with crystalline or amorphous boron or the RhB precursor. The crystal structure of Mg{sub 8}Rh{sub 4}B was solved using single-crystal X-ray diffraction data (space group Fd3-bar m, a=12.1711(4)A, Z=8, 174 reflections, R{sub F}=0.016). The crystal structure can be described as a filled Ti{sub 2}Ni type where the interstitial sites 8b (12,12,12), located at the center of two nested Mg{sub 4}Rh{sub 4} tetrahedra, are occupied by boron atoms. Taking into account the absence of the Ti{sub 2}Ni-type phase in the binary Mg-Rh system, the boron atoms can be considered as stabilizing this structural motif. From the bonding analysis with the electron localization function the crystal structure is described as covalently bonded [Rh{sub 4}B]{sup 3-} anions, embedded in a cationic magnesium matrix.

  8. Structural investigation and microwave characteristics of (Ba0.2La0.8)Fe0.2Mn0.4Ti0.4O3 absorbing materials

    NASA Astrophysics Data System (ADS)

    Manaf, Azwar; Adi, Wisnu Ari

    2014-03-01

    Synthesis and characterization of (Ba0.2La0.8)Fe0.2Mn0.4Ti0.4O3 absorbing material by mechanical alloying process has been performed. The absorbing material was prepared by oxide materials, namely BaCO3, La2O3, TiO2, Fe2O3, and MnCO3. The mixture was milled for 10 h and then sintered at a temperature of 1000 ° C for 10 h. The refinement results of x-ray diffraction pattern of lanthanum manganite substituted with barium showed that the sample consisted of two phases, namely, La0.9125MnO3 phase which has a structure monoclinic (I12/a1) with lattice parameters a = 5.527(1) Å, b = 5.572(1) Å and c = 7.810(1) Å, α = γ = 90° and β = 89.88(5)°, the unit cell volume of V = 240.57(8) Å3, and the atomic density of ρ = 6.238 gr.cm-3. The microstructure analyses showed that the particle shapes was polygonal with the varied particle sizes of 1 ˜ 3 μm distributed homogeneously on the surface of the samples. The results of the electromagnetic wave absorption curve analysis by using a vector network analyzer (VNA) showed that the sample can absorb microwaves in the frequency range of 8-15 GHz with a very wide absorption bandwidth. It indicates that the as prepared absorber presents potential absorbing property in X and Ku-band. We concluded that the (Ba0.2La0.8)Fe0.2Mn0.4Ti0.4O3 material can be applied as a candidate absorber material of microwaves or electromagnetic wave.

  9. The Expression of Programmed Death-1 on CD4+ and CD8+ T Lymphocytes in Patients with Type 2 Diabetes and Severe Sepsis

    PubMed Central

    Li, Chunsheng; Shao, Rui

    2016-01-01

    Objective To investigate the expression of Programmed death-1 (PD-1) on T lymphocytes in patients with type 2 diabetes mellitus (T2DM) and severe sepsis, we determined PD-1 expression on CD4+ and CD8+ T lymphocytes of patients with T2DM, severe sepsis, and T2DM combined with severe sepsis. Research Design and Methods This prospective and observational study included 50 healthy controls, 80 cases of T2DM without infection (T2DM group), 88 cases of severe sepsis without T2DM (SS group), and 77 cases of severe sepsis combined with T2DM (SS+T2DM group). Expression of peripheral blood PD-1+ CD4+ T cells and PD-1+ CD8+ T cells were compared between these 4 groups. Then, 28-day survival of the SS and SS+T2DM patients was assessed, and the expression of PD-1 on T cells was also compared between survivors and non-survivors. Results Percentages of PD-1+ CD4+ T cells and PD-1+ CD8+ T cells were higher in the T2DM group than in the healthy control group, and were highest in the SS and SS+T2DM groups. However, the expression of PD-1 on T cells and the mortality showed no significant difference between the SS and SS+T2DM groups. The expression of PD-1 on T cells was higher in non-survivors than survivors, but within the survivor group or non-survivor group, no difference can be detected between those with T2DM and those without T2DM. Conclusion The expression of PD-1 on T cells was increased in both T2DM and severe septic patients, but combining T2DM did not cause a further increase on the PD-1 expression in patients with severe sepsis. PMID:27459386

  10. Platinum carbonyl clusters stabilized by Sn(ii)-based fragments: syntheses and structures of [Pt6(CO)6(SnCl2)2(SnCl3)4](4-), [Pt9(CO)8(SnCl2)3(SnCl3)2(Cl2SnOCOSnCl2)](4-) and [Pt10(CO)14{Cl2Sn(OH)SnCl2}2](2.).

    PubMed

    Bortoluzzi, Marco; Ceriotti, Alessandro; Ciabatti, Iacopo; Della Pergola, Roberto; Femoni, Cristina; Carmela Iapalucci, Maria; Storione, Alba; Zacchini, Stefano

    2016-03-15

    The reaction of [Pt15(CO)30](2-) with increasing amounts of SnCl2 affords [Pt8(CO)10(SnCl2)4](2-) (), [Pt10(CO)14{Cl2Sn(OH)SnCl2}2](2-) (), [Pt6(CO)6(SnCl2)2(SnCl3)4](4-) (), [Pt9(CO)8(SnCl2)3(SnCl3)2(Cl2SnOCOSnCl2)](4-) () and [Pt5(CO)5{Cl2Sn(OR)SnCl2}3](3-) (R = H, Me, Et, and (i)Pr) (). and have been previously described, whereas are herein reported for the first time. The species are the main products of the reaction under different experimental conditions, whereas and are by-products of the synthesis of and , respectively. From a structural point of view, the clusters all show a perfect segregation of the two metals, which are composed of a low valent Pt core decorated on the surface by Sn(ii) fragments such as SnCl2, [SnCl3](-), [Cl2Sn(OH)SnCl2](-) and [Cl2SnOCOSnCl2](2-). These fragments behave as two electron donor ligands via each Sn-atom (and also the C-atom in the case of [Cl2SnOCOSnCl2](2-)). The [Cl2SnOCOSnCl2](2-) ligand is rather unique and may be viewed as a bis-stannyl-carboxylate, a carbon dioxide μ3:k(3)-C,O,O'-CO2 or a carbonite ion [CO2](2-) stabilized by coordination to metal atoms. Compounds have been fully characterised via IR spectroscopy, X-ray crystallography and DFT calculations. PMID:26795720

  11. Critical current, magnetization relaxation and activation energies for YBa 2Cu 3O 7 and YBa 2Cu 4O 8 films

    NASA Astrophysics Data System (ADS)

    Wen, Hai-hu; Schnack, H. G.; Griessen, R.; Dam, B.; Rector, J.

    1995-02-01

    By means of high-sensitivity capacitance torque magnetometers we have measured the superconducting current js and the dynamic magnetic-moment relaxation of YBa 2Cu 3O 7 and YBa 2Cu 4O 8 films of typically 100 nm thickness at temperatures between 2 K and Tc in magnetic fields up to 6 T. For the measurements of the dynamic relaxation rate Q≡d ln js/d ln (d Be/d t) magnetic-field sweep rates were varied between 0.5 and 40 mT/s. At low fields (typically 0.5 T) the dynamical relaxation rate exhibits a plateau at Q≈0.06 in YBa 2Cu 3O 7 and 0.04 in YBa 2Cu 4O 8. At high fields ( Be= μ0He≈ 6 T) the plateaus have completely disappeared and Q increases almost linearly with increasing temperature. At all fields a sharp increase up to Q≊1 is observed when the irreversibility line is approached. By means of the generalized inversion scheme (GIS), the js( T, Be) and Q ( T, Be) data are used to determined the current dependent activation energy U ( j, T, Be) for thermally activted flux creep. Although the GIS does not make any a priori assumptions about the explicit functional dependences on T and j, the U( j, T=0, Be) function derived from the experimental data by means of the GIS can remarkably well be described with the collective-creep interpolation formula U( j)=( Uc/ μ)[( jc/ j) μ-1] with μ≈0.6 for currents j>0.15 jc ( T=0, Be) where Jc( T=0, Be) is the critical current at T=0, and wi Uc depending on Be. At lower current densities U( j, T=0, Be) does not diverge as j-0.6 but shifts gradually to a weaker ln( jc/ j) dependence. At low temperatures the current and relaxation data cannot be explained in terms of a thermally activated flux-motion model. Quantum creep has an influence up to ˜13 K.

  12. Tuning magnetization, blocking temperature, cation distribution of nanosized Co0.2Zn0.8Fe2O4 by mechanical activation

    NASA Astrophysics Data System (ADS)

    Dey, S.; Mondal, R.; Dey, S. K.; Majumder, S.; Dasgupta, P.; Poddar, A.; Reddy, V. R.; Kumar, S.

    2015-09-01

    The study on structural, microstructural, magnetic, and hyperfine properties of nanosized Co0.2Zn0.8Fe2O4 having particle size ˜18 nm (CZM) synthesized by high energy ball milling of Co0.2Zn0.8Fe2O4 nanoparticles of size ˜20 nm (CZ) produced by flow rate controlled coprecipitation method has revealed that the inclusion of strain induced anisotropy produced by mechanical treatment and escalation of oxygen mediated intersublattice exchange interaction of spinel ferrites by tuning cation distribution properly, can improve the magnetic quality of nanosized ferrites significantly. This upshot will be of immense help in promoting the technological application of nanostructured ferrites. The Rietveld refinement of powder x-ray diffraction pattern and the analysis of transmission electron micrographs, energy dispersive x-ray spectrum, and FTIR spectrum of the sample have confirmed that CZM is single phase cubic nanometric spinel ferrite of Fd 3 ¯ m symmetry and it possesses large microstrain within its crystal lattice. The dc magnetic and Mössbauer spectroscopic studies together with indicate that the particles in the sample are composed of ferrimagnetically aligned core and spin-glass like shell and the system behaves superparamagnetically at 300 K. The saturation magnetization (44 and 87 emu g-1 at 300 and 10 K) and hyperfine field of the sample are substantially higher than its counterparts reported earlier. In spite of its lower size compared to CZ, the blocking temperature (˜220 K) of CZM is higher than that of CZ (70 K) and also that of its counterparts synthesized by chemical methods. The strengthening of the intersublattice A-O-B superexchange interaction because of migration of Fe3+ ions from octahedral [B] to tetrahedral (A) sites in lieu of the relocation of Zn2+ among (A) and [B] sites helps in enhancement of magnetization and hyperfine field of CZM. The giant coercivity (HC ˜ 5600 Oe at 10 K) of CZM is accounted by the presence of spin glass like surface

  13. 6-amino-4-oxo-1,3-diphenyl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonyl derivatives as a new class of potent inhibitors of Interleukin-8-induced neutrophil chemotaxis.

    PubMed

    Cesarini, Sara; Spallarossa, Andrea; Ranise, Angelo; Bruno, Olga; Arduino, Nicoletta; Bertolotto, Maria; Dallegri, Franco; Tognolini, Massimiliano; Gobbetti, Thomas; Barocelli, Elisabetta

    2009-05-15

    A series of 6-amino-4-oxo-1,3-diphenyl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonyl derivatives was synthesized. The compounds demonstrated to be novel, potent and selective inhibitors of Interleukin-8-induced human neutrophil chemotaxis. A SAR study was performed by varying the carbonyl function at position 5 and the chain linked to the amino group at position 6 of the scaffold. All the compounds of the series displayed inhibitory activity at nano- or picomolar concentrations against Interleukin-8-driven migration and no activity against fMLP- and C5a-induced chemotaxis. The binding tests of selected compounds on CXCR1 and CXCR2 receptors were negative. The most potent derivative showed in vivo efficacy in a mouse model of Zymosan-induced peritonitis. PMID:19394230

  14. Novel methyl substituted 1-(5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanones are P2X7 antagonists.

    PubMed

    Rudolph, Dale A; Alcazar, Jesus; Ameriks, Michael K; Anton, Ana Belen; Ao, Hong; Bonaventure, Pascal; Carruthers, Nicholas I; Chrovian, Christa C; De Angelis, Meri; Lord, Brian; Rech, Jason C; Wang, Qi; Bhattacharya, Anindya; Andres, Jose Ignacio; Letavic, Michael A

    2015-08-15

    The optimization efforts that led to a novel series of methyl substituted 1-(5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)methanones that are potent rat and human P2X7 antagonists are described. These efforts resulted in the discovery of compounds with good drug-like properties that are capable of high P2X7 receptor occupancy in rat following oral administration, including compounds 7n (P2X7 IC50 = 7.7 nM) and 7u (P2X7 IC50 =7 .7 nM). These compounds are expected to be useful tools for characterizing the effects of P2X7 antagonism in models of depression and epilepsy, and several of the compounds prepared are candidates for effective P2X7 PET tracers. PMID:26099534

  15. 15 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 1 2012-01-01 2012-01-01 false Discrimination prohibited. 8.4 Section... General Provisions; Prohibitions: Nondiscrimination Clause; Applicability to Programs § 8.4 Discrimination... discrimination under, any program to which this part applies. (b) Specific discriminatory acts prohibited. (1)...

  16. 15 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 1 2014-01-01 2014-01-01 false Discrimination prohibited. 8.4 Section... General Provisions; Prohibitions: Nondiscrimination Clause; Applicability to Programs § 8.4 Discrimination... discrimination under, any program to which this part applies. (b) Specific discriminatory acts prohibited. (1)...

  17. 15 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 1 2011-01-01 2011-01-01 false Discrimination prohibited. 8.4 Section... General Provisions; Prohibitions: Nondiscrimination Clause; Applicability to Programs § 8.4 Discrimination... discrimination under, any program to which this part applies. (b) Specific discriminatory acts prohibited. (1)...

  18. 15 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 1 2013-01-01 2013-01-01 false Discrimination prohibited. 8.4 Section... General Provisions; Prohibitions: Nondiscrimination Clause; Applicability to Programs § 8.4 Discrimination... discrimination under, any program to which this part applies. (b) Specific discriminatory acts prohibited. (1)...

  19. 24 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 1 2011-04-01 2011-04-01 false Discrimination prohibited. 8.4... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT General Provisions § 8.4 Discrimination prohibited. (a) No... in, be denied the benefits of, or otherwise be subjected to discrimination under any program...

  20. 24 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Discrimination prohibited. 8.4... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT General Provisions § 8.4 Discrimination prohibited. (a) No... in, be denied the benefits of, or otherwise be subjected to discrimination under any program...

  1. 24 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Discrimination prohibited. 8.4... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT General Provisions § 8.4 Discrimination prohibited. (a) No... in, be denied the benefits of, or otherwise be subjected to discrimination under any program...

  2. 24 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Discrimination prohibited. 8.4... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT General Provisions § 8.4 Discrimination prohibited. (a) No... in, be denied the benefits of, or otherwise be subjected to discrimination under any program...

  3. 24 CFR 8.4 - Discrimination prohibited.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Discrimination prohibited. 8.4... DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT General Provisions § 8.4 Discrimination prohibited. (a) No... in, be denied the benefits of, or otherwise be subjected to discrimination under any program...

  4. 27 CFR 8.4 - Jurisdictional limits.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Jurisdictional limits. 8.4 Section 8.4 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF...) The direct effect of the requirement is to prevent, deter, hinder, or restrict other persons...

  5. Two oxo complexes with tetranuclear [Fe(4)(mu(3)-O)(2)](8+) and trinuclear [Fe(3)(mu(3)-O)](7+) units.

    PubMed

    Cortés, Piedad; Atria, Ana María; Garland, María Teresa; Baggio, Ricardo

    2006-07-01

    Two new oxo complexes, namely hexa-mu(2)-acetato-acetatoaquabis(di-3-pyridylamine)di-mu(3)-oxo-tetrairon(III) chloride monohydrate ethanol 1.25-solvate, [Fe(4)(C(2)H(3)O(2))(7)O(2)(C(10)H(9)N(3))(2)(H(2)O)]Clx1.25C(2)H(6)OxH(2)O, (I), containing a tetranuclear [Fe(4)(mu(3)-O)(2)](8+) unit, and 2-methylimidazolium hexa-mu(2)-acetato-acetatodiaqua-mu(3)-oxo-triiron(III) chloride dihydrate, (C(4)H(7)N(2))[Fe(3)(C(2)H(3)O(2))(7)O(H(2)O)(2)]Clx2H(2)O, (II), with a trinuclear [Fe(3)(mu(3)-O)](7+) unit, are presented. Both structures are formed by two well differentiated entities, viz. a compact isolated cluster composed of Fe(III) ions coordinated to O(2-) and CH(3)CO(2)(-) anions, and an external group formed by a central Cl(-) ion surrounded by different solvent groups to which the anion is bound through hydrogen bonding. In the case of (I), charge balance cannot be achieved within the groups, so the structure is macroscopically ionic; in the case of (II), in contrast, each group is locally neutral owing to the internal compensation of charges. The trinuclear complex crystallizes with the metal cluster, chloride anion and 2-methylimidazolium cation bisected by a crystallographic mirror plane. PMID:16823197

  6. Lack of activity of 15-epi-lipoxin A4 on FPR2/ALX and CysLT1 receptors in interleukin-8-driven human neutrophil function

    PubMed Central

    Planagumà, A; Domenech, T; Jover, I; Ramos, I; Sentellas, S; Malhotra, R; Miralpeix, M

    2013-01-01

    Neutrophil recruitment and survival are important control points in the development and resolution of inflammatory processes. 15-epi-lipoxin (LX)A4 interaction with formyl peptide receptor 2 (FPR2)/ALX receptor is suggested to enhance anti-inflammatory neutrophil functions and mediate resolution of airway inflammation. However, it has been reported that 15-epi-LXA4 analogues can also bind to cysteinyl leukotriene receptor 1 (CysLT1) and that the CysLT1 antagonist MK-571 binds to FPR2/ALX, so cross-reactivity between FPR2/ALX and CysLT1 ligands cannot be discarded. It is not well established whether the resolution properties reported for 15-epi-LXA4 are mediated through FPR2/ALX, or if other receptors such as CysLT1 may also be involved. Evaluation of specific FPR2/ALX ligands and CysLT1 antagonists in functional biochemical and cellular assays were performed to establish a role for both receptors in 15-epi-LXA4-mediated signalling and function. In our study, a FPR2/ALX synthetic peptide (WKYMVm) and a small molecule FPR2/ALX agonist (compound 43) induced FPR2/ALX-mediated signalling, enhancing guanosine triphosphate-gamma (GTPγ) binding and decreasing cyclic adenosine monophosphate (cAMP) levels, whereas 15-epi-LXA4 was inactive. Furthermore, 15-epi-LXA4 showed neither binding affinity nor signalling towards CysLT1. In neutrophils, 15-epi-LXA4 showed a moderate reduction of interleukin (IL)-8-mediated neutrophil chemotaxis but no effect on neutrophil survival was observed. In addition, CysLT1 antagonists were inactive in FPR2/ALX signalling or neutrophil assays. In conclusion, 15-epi-LXA4 is not a functional agonist or an antagonist of FPR2/ALX or CysLT1, shows no effect on IL-8-induced neutrophil survival and produces only moderate inhibition in IL-8-mediated neutrophil migration. Our data do not support an anti-inflammatory role of 15-epi-LXA4- FPR2/ALX interaction in IL-8-induced neutrophil inflammation. PMID:23607720

  7. Is Octavalent Pu(VIII) Possible? Mapping the Plutonium Oxyfluoride Series PuO(n)F(8-2n) (n = 0-4).

    PubMed

    Huang, Wei; Pyykkö, Pekka; Li, Jun

    2015-09-01

    While the oxidation state Pu(VIII) is shown to be less stable than Pu(V) in the PuO4 molecule, it is not clear if the more electronegative fluorine can help to stabilize Pu(VIII). Our calculations on PuO(n)F(8-2n) (n = 0-4) molecules notably confirm that PuO2F4 has both (1)D(4h) and (5)C(2v) minima with the oxidation states Pu(VIII) and Pu(V), respectively, with the latter having lower energy. The hybrid-DFT, CCSD(T), and CASSCF methods all give the same result. The results conform to a superoxide ligand when n ≥ 2. PuF8 in a (1)O(h) state can decompose to PuF6 and F2, and PuOF6 in a (1)C(2v) state also can break down to PuF6 and 1/2 O2. The Pu(VIII) anion PuO2F5(-) does have a D(5h) minimum, which also lies above a (5)C(2v) Pu(V) peroxide structure. However, the energy differences between the different minima are not large, indicating that metastable species with oxidation states higher than Pu(V) cannot be completely excluded. PMID:26309065

  8. Dentin is dissolved by high concentrations of L-ascorbic acid 2-[3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl-hydrogen phosphate] potassium salt with or without hydrogen peroxide.

    PubMed

    Kozuka, Masahiro; Tsujimoto, Yasuhisa

    2004-06-01

    L-Ascorbic acid 2-[3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl-hydrogen phosphate] potassium salt (EPC-K(1)) is a conjugate of vitamin C and vitamin E that is water-soluble and stable at room temperature. EPC-K(1) has been developed as a hydroxyl radical (.OH) scavenger and antioxidant. In a previous tooth whitening experiment, it was accidentally found that tooth (dentin) blocks were dissolved by EPC-K(1) with H(2)O(2). In the current study, high concentrations of EPC-K(1) (2.5, 25 mM) with 3% H(2)O(2) dissolved and caused the collapse of dentin blocks. Similar concentrations of EPC-K(1) without 3% H(2)O(2), however, dissolved the dentin blocks without collapse over a 3-week period. In these cases, a.OH-like signal was detected using an ESR spin-trapping method. The volume of calcium in solution (including the dentin block) increased on the addition of EPC-K(1) in a concentration-dependent manner. In addition, the calcium : phosphorus ratio changed from 2 : 1 in sound dentin to 1 : 2 in the collapsed dentin block. High concentrations of EPC-K(1) are therefore considered to have calcium chelating and dentin dissolving activity. The dentin dissolving activity was enhanced when EPC-K(1) was used with H(2)O(2). EPC-K(1) had no protective effect when used in tooth whitening with H(2)O(2). PMID:15187428

  9. Two-dimensional zeolite-like network in the new caesium copper aluminate Cs2CuAl4O8.

    PubMed

    Shvanskaya, Larisa; Yakubovich, Olga; Massa, Werner; Vasiliev, Alexander

    2015-10-01

    Monoclinic dicaesium copper tetraaluminate, Cs2CuAl4O8, space group P2(1)/c, a = 8.4551 (7), b = 10.012 (1), c = 17.073 (2) Å, β = 101.643 (9)°, Z = 6, was obtained by high-temperature crystallization from a phosphate flux. Its microporous crystal structure presents the first example of double layers built from [AlO4] tetrahedra combined in 4-, 6- and 8-rings, topologically similar to those found in the ATT-type zeolites and isostructural minerals armstrongite, davanite and dalyite. These layers show a rare arrangement of three [AlO4] tetrahedra sharing one oxygen vertex. The aluminate slabs are further linked by chains of edge-sharing [CuO4] square planes to form a mixed anionic three-dimensional framework with Cs(+) cations in channels and cavities. An unusually short Cu···Cs distance of 3.166 Å is ascribed to the strong Jahn-Teller effect of Cu(2+). The magnetic subsystem demonstrates properties of an alternating antiferromagnetic chain with a gap in the spectrum of magnetic excitations. PMID:26428399

  10. Quantitative-Trait Loci on Chromosomes 1, 2, 3, 4, 8, 9, 11, 12, and 18 Control Variation in Levels of T and B Lymphocyte Subpopulations

    PubMed Central

    Hall, M. A.; Norman, P. J.; Thiel, B.; Tiwari, H.; Peiffer, A.; Vaughan, R. W.; Prescott, S.; Leppert, M.; Schork, N. J.; Lanchbury, J. S.

    2002-01-01

    Lymphocyte subpopulation levels are used for prognosis and monitoring of a variety of human diseases, especially those with an infectious etiology. As a primary step to defining the major gene variation underlying these phenotypes, we conducted the first whole-genome screen for quantitative variation in lymphocyte count, CD4 T cell, CD8 T cell, B cell, and natural killer cell numbers, as well as CD4:CD8 ratio. The screen was performed in 15 of the CEPH families that form the main human genome genetic project mapping resource. Quantitative-trait loci (QTLs) that account for significant proportions of the phenotypic variance of lymphocyte subpopulations were detected on chromosomes 1, 2, 3, 4, 8, 9, 11, 12, and 18. The most significant QTL found was for CD4 levels on chromosome 8 (empirical P=.00005). Two regions of chromosome 4 showed significant linkage to CD4:CD8 ratio (empirical P=.00007 and P=.003). A QTL for the highly correlated measures of CD4 and CD19 levels colocalized at 18q21 (both P=.003). Similarly, a shared region of chromosome 1 was linked to CD8 and CD19 levels (P=.0001 and P=.002, respectively). Several of the identified chromosome regions are likely to harbor polymorphic candidate genes responsible for these important human phenotypes. Their discovery has important implications for understanding the generation of the immune repertoire and understanding immune-system homeostasis. More generally, these data show the power of an integrated human gene–mapping approach for heritable molecular phenotypes, using large pedigrees that have been extensively genotyped. PMID:11951176

  11. Synthesis and characterization of N, N'-bis[2-hydroxyethyl]-1,4,6,8-naphthalenediimide with para substituted of phenols based on charge-transfer complexes

    NASA Astrophysics Data System (ADS)

    Refat, Moamen S.; Killa, Hamada M. A.; Grabchev, Ivo; El-Sayed, Mohamed Y.

    2007-09-01

    The interaction of charge-transfer (CT) complexes resulted from the reaction of N, N'-bis[2-hydroxyethyl]-1,4,6,8-naphthalenediimide (BHENDI) with some various acceptors like as substituted phenols in para position; 4-aminophenol (4AP), 4-methylphenol (4MP) and 4-nitrophenol (4NP) have been studied in methanol at room temperature. The reaction was studied using electronic (UV-vis), mid infrared, and 1H NMR spectra and thermal measurements (TGA and DTG) as well as elemental analysis CHN. The chemical analysis data of the resulted CT-complexes, BHENDI-acceptors, reveal that the formation of a 1:2 CT complexes in all cases. The interaction of N, N'-bis[2-hydroxyethyl]-1,4,6,8-naphthalenediimide and phenolic acceptors were investigated spectrophotometrically and found two detected CT bands have n-π * transition. The donor site involved in CT interaction is the diimide two nitrogen atoms by forming hydrogen bonding. The kinetic thermodynamic parameters like Δ E, Δ H, Δ S and Δ G are calculated from the DTG diagrams using Coats-Redfern method. The electrical conductivity properties for the solid CT complexes were measured within the temperature of room 25 °C.

  12. Addition polymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and Bis-dienes. 2: Evidence for thermal dehydration occurring in the cure process

    NASA Technical Reports Server (NTRS)

    Meador, Mary Ann B.; Olshavsky, Michael A.; Meador, Michael A.; Ahn, Myong-Ku

    1988-01-01

    Diels-Alder cycloaddition copolymers from 1,4,5,8-tetrahydro-1,4;5,8-diepoxyanthracene and anthracene end-capped polyimide oligomers appear, by thermogravimetric analysis (TGA), to undergo dehydration at elevated temperatures. This would produce thermally stable pentiptycene units along the polymer backbone, and render the polymers incapable of unzipping through a retro-Diels-Alder pathway. High resolution solid 13C nuclear magnetic resonance (NMR) of one formulation of the polymer system before and after heating at elevated temperatures, shows this to indeed be the case. NMR spectra of solid samples of the polymer before and after heating correlated well with those of the parent pentiptycene model compound before and after acid-catalyzed dehydration. Isothermal gravimetric analyses and viscosities of the polymer before and after heat treatment support dehydration as a mechanism for the cure reaction.

  13. 4 CFR 22.8 - General Discovery Procedures [Rule 8].

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... OFFICE CONTRACT APPEALS BOARD § 22.8 General Discovery Procedures . (a) General policy and methods of... things, or entry onto land. (b) Scope of discovery. Except as otherwise limited by order of the Board... accordance with § 22.4(a) of this part , the parties shall confer and file with the Board a...

  14. Infrared and Raman spectroscopic characterization of the silicate-carbonate mineral carletonite - KNa4Ca4Si8O18(CO3)4(OH,F)·H2O

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; Xi, Yunfei; Scholz, Ricardo; López, Andrés; Belotti, Fernanda Maria

    2013-06-01

    An assessment of the molecular structure of carletonite a rare phyllosilicate mineral with general chemical formula given as KNa4Ca4Si8O18(CO3)4(OH,F)·H2O has been undertaken using vibrational spectroscopy. Carletonite has a complex layered structure. Within one period of c, it contains a silicate layer of composition NaKSi8O18·H2O, a carbonate layer of composition NaCO3·0.5H2O and two carbonate layers of composition NaCa2CO3(F,OH)0.5. Raman bands are observed at 1066, 1075 and 1086 cm-1. Whether these bands are due to the CO32- ν1 symmetric stretching mode or to an SiO stretching vibration is open to question. Multiple bands are observed in the 300-800 cm-1 spectral region, making the attribution of these bands difficult. Multiple water stretching and bending modes are observed showing that there is much variation in hydrogen bonding between water and the silicate and carbonate surfaces.

  15. Synthesis and structure-activity relationships of 3,8-diazabicyclo[4.2.0]octane ligands, potent nicotinic acetylcholine receptor agonists.

    PubMed

    Frost, Jennifer M; Bunnelle, William H; Tietje, Karin R; Anderson, David J; Rueter, Lynne E; Curzon, Peter; Surowy, Carol S; Ji, Jianquo; Daanen, Jerome F; Kohlhaas, Kathy L; Buckley, Michael J; Henry, Rodger F; Dyhring, Tino; Ahring, Philip K; Meyer, Michael D

    2006-12-28

    A series of potent neuronal nicotinic acetylcholine receptor (nAChR) ligands based on a 3,8-diazabicyclo[4.2.0]octane core have been synthesized and evaluated for affinity and agonist efficacy at the human high affinity nicotine recognition site (halpha4beta2) and in a rat model of persistent nociceptive pain (formalin model). Numerous analogs in this series exhibit picomolar affinity in radioligand binding assays and nanomolar agonist potency in functional assays, placing them among the most potent nAChR ligands known for the halpha4beta2 receptor. Several of the compounds reported in this study (i.e., 24, 25, 28, 30, 32, and 47) exhibit equivalent or greater affinity for the halpha4beta2 receptor relative to epibatidine, and like epibatidine, many exhibit robust analgesic efficacy in the rat formalin model of persistent pain. PMID:17181167

  16. Superparamagnetic behavior of nanosized Co0.2Zn0.8Fe2O4 synthesized by a flow rate controlled chemical coprecipitation method

    NASA Astrophysics Data System (ADS)

    Dey, S.; Dey, S. K.; Majumder, S.; Poddar, A.; Dasgupta, P.; Banerjee, S.; Kumar, S.

    2014-09-01

    We have studied the structural, microstructural and magnetic properties of nanosized (~20 nm) Co0.2Zn0.8Fe2O4 synthesized by a flow rate controlled coprecipitation method. The phase purity and crystallinity of the sample have been confirmed by powder X-ray diffraction and high resolution transmission electron microscopic studies. According to the results of dc magnetic measurements the sample exhibits superparamagnetic behavior above 70 K due to its nanometric size. This has been corroborated by Mössbauer spectroscopic study at 300 K. The infield Mössbauer spectroscopic study indicates that the sample behaves ferrimagnetically at 10 K and it possesses equilibrium cation distribution. The saturation magnetization of the sample (MSAT~32 emu g-1 at 300 K) is substantially lower than its bulk counterpart (MSAT=80 emu g-1) but higher than those having same composition synthesized by the conventional coprecipitation method. This has been attributed to finite size and spin canting effects as well as good crystalline character and bulk like equilibrium cation distribution of the sample. We have shown that the flow rate controlled coprecipitation method can produce nanosized ferrites with very good crystalline order and equilibrium cation distribution but they exhibit reduction of magnetization, magnetic order and ordering temperature compared to their bulk counterparts due to spin canting effect and finite size effect.

  17. Chiral-selective CoSO4/SiO2 catalyst for (9,8) single-walled carbon nanotube growth.

    PubMed

    Wang, Hong; Wei, Li; Ren, Fang; Wang, Qiang; Pfefferle, Lisa D; Haller, Gary L; Chen, Yuan

    2013-01-22

    Electronic and optical properties of single-walled carbon nanotubes (SWCNTs) correlate with their chiral structures. Many applications need chirally pure SWCNTs that current synthesis methods cannot produce. Here, we show a sulfate-promoted CoSO(4)/SiO(2) catalyst, which selectively grows large-diameter (9,8) nanotubes at 1.17 nm with 51.7% abundance among semiconducting tubes and 33.5% over all tube species. After reduction in H(2) at 540 °C, the catalyst containing 1 wt % Co has a carbon yield of 3.8 wt %, in which more than 90% is SWCNT. As compared to other Co catalysts used for SWCNT growth, the CoSO(4)/SiO(2) catalyst is unique with a narrow Co reduction window under H(2) centered at 470 °C, which can be attributed to the reduction of highly dispersed CoSO(4). X-ray absorption spectroscopy (XAS) results suggested the formation of Co particles with an average size of 1.23 nm, which matches the diameter of (9,8) tubes. Density functional theory study indicated that the diameter of structurally stable pure Co particles is scattered, matching the most abundant chiral tubes, such as (6,5) and (9,8). Moreover, the formation of such large Co particles on the CoSO(4)/SiO(2) catalyst depends on sulfur in the catalyst. XAS results showed that sulfur content in the catalyst changes after catalyst reduction at different conditions, which correlates with the change in (n,m) selectivity observed. We proposed that the potential roles of sulfur could be limiting the aggregation of Co atoms and/or forming Co-S compounds, which enables the chiral selectivity toward (9,8) tubes. This work demonstrates that catalysts promoted with sulfur compounds have potentials to be further developed for chiral-selective growth of SWCNTs. PMID:23215361

  18. 6-(4-Amino-2-butyl-imidazoquinolyl)-norleucine: Toll-like receptor 7 and 8 agonist amino acid for self-adjuvanting peptide vaccine.

    PubMed

    Fujita, Yoshio; Hirai, Kazuyuki; Nishida, Keigo; Taguchi, Hiroaki

    2016-05-01

    Generally, small peptides by themselves are weak to induce antibody responses. Toll-like receptor (TLR) ligands are attractive candidates of vaccine adjuvants to improve their antigenicity. The covalent conjugation of TLR ligands with antigens to produce self-adjuvanting peptide vaccine is a promising approach. Based on the structure of TLR7/8 ligands, a series of synthetic amino acids 6-imidazoquinolyl-norleucines were synthesized, wherein an imidazoquinoline structure as the TLR7/8 agonistic pharmacophores was constructed on the ε-NH2 group of Lys. Of them, 6-(4-amino-2-butyl-imidazoquinolyl)-norleucine showed the most potent TLR7 and TLR8 agonistic activities with EC50 values of 8.55 and 106 μM, respectively. Subsequently, mice were immunized with the influenza A virus M2e antigen mixed with or covalently conjugated to the TLR7/8 agonist amino acid, which led to induction of M2e specific antibody productions in the absence of other adjuvant. We successfully developed a novel efficient tool for self-adjuvanting peptide vaccines targeting TLR7/8. PMID:26874701

  19. 3,3,6,6-Tetra-methyl-9-[6-(3,3,6,6-tetra-methyl-1,8-dioxo-2,3,4,5,6,7,8,9-octa-hydro-1H-xanthen-9-yl)pyridin-2-yl]-2,3,4,5,6,7,8,9-octa-hydro-1H-xanthene-1,8-dione.

    PubMed

    Abdelhamid, Antar A; Mohamed, Shaaban Kamel; Allahverdiyev, Mirze A; Gurbanov, Atash V; Ng, Seik Weng

    2011-04-01

    In the title mol-ecule, C(39)H(45)NO(6), the two tetra-methyl-octa-hydroxanthen-1,8-dione substituents are arranged approximately parallel to each other and approximately perpendicular to the plane of the pyridine ring. The six-membered xanthene rings adopt flattened boat conformations with the O and methine C atoms deviating from the plane of the other four atoms. PMID:21754076

  20. 8 CFR 100.4 - Field offices.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Field offices. 100.4 Section 100.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS STATEMENT OF ORGANIZATION § 100.4 Field offices. (a) Ports-of-Entry for aliens arriving by vessel or by land transportation. Subject to the limitations prescribed in...

  1. 8 CFR 100.4 - Field offices.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Field offices. 100.4 Section 100.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS STATEMENT OF ORGANIZATION § 100.4 Field offices. (a) Ports-of-Entry for aliens arriving by vessel or by land transportation. Subject to the limitations prescribed in...

  2. 8 CFR 100.4 - Field offices.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Field offices. 100.4 Section 100.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS STATEMENT OF ORGANIZATION § 100.4 Field offices. (a) Ports-of-Entry for aliens arriving by vessel or by land transportation. Subject to the limitations prescribed in...

  3. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  4. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  5. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  6. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  7. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  8. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  9. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  10. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  11. 8 CFR 328.4 - Application.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Application. 328.4 Section 328.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY NATIONALITY REGULATIONS SPECIAL CLASSES OF PERSONS WHO MAY BE NATURALIZED: PERSONS WITH THREE YEARS SERVICE IN ARMED FORCES OF THE UNITED STATES § 328.4 Application....

  12. 8 CFR 101.4 - Registration procedure.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Registration procedure. 101.4 Section 101.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS PRESUMPTION OF LAWFUL ADMISSION § 101.4 Registration procedure. The procedure for an application for creation of a record...

  13. 8 CFR 101.4 - Registration procedure.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Registration procedure. 101.4 Section 101.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS PRESUMPTION OF LAWFUL ADMISSION § 101.4 Registration procedure. The procedure for an application for creation of a record...

  14. 8 CFR 1244.4 - Ineligible aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Ineligible aliens. 1244.4 Section 1244.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 1244.4 Ineligible aliens. An...

  15. 8 CFR 244.4 - Ineligible aliens.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Ineligible aliens. 244.4 Section 244.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS TEMPORARY PROTECTED STATUS FOR NATIONALS OF DESIGNATED STATES § 244.4 Ineligible aliens. An alien is ineligible for...

  16. 8 CFR 325.4 - Application; documents.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Application; documents. 325.4 Section 325.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY NATIONALITY REGULATIONS NATIONALS BUT NOT CITIZENS OF THE UNITED STATES; RESIDENCE WITHIN OUTLYING POSSESSIONS § 325.4 Application; documents. (a)...

  17. 8 CFR 325.4 - Application; documents.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Application; documents. 325.4 Section 325.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY NATIONALITY REGULATIONS NATIONALS BUT NOT CITIZENS OF THE UNITED STATES; RESIDENCE WITHIN OUTLYING POSSESSIONS § 325.4 Application; documents. (a)...

  18. Synthesis, in vitro antimycobacterial evaluation and docking studies of some new 5,6,7,8-tetrahydropyrido[4',3':4,5]thieno[2,3-d]pyrimidin-4(3H)-one schiff bases.

    PubMed

    Malothu, Narender; Bhandaru, Jaswanth S; Kulandaivelu, Umasankar; Jojula, Malathi; Adidala, Raghuram Reddy; K R, Umadevi; A V N, Dusthackeer; Kaki, Venkat Rao; Akkinepally, Raghuram R

    2016-02-01

    Development of multidrug resistant (MDR) and extensively drug resistant (XDR) tuberculosis (TB) has been considered as major health burden, globally. In order to develop novel, potential molecules against drug resistant TB, twenty two (22) new 3-substituted-7-benzyl-5,6,7,8-tetrahydropyrido[4',3':4,5]thieno[2,3-d]pyrimidin-4(3H)-one (6a-k) and 3-substituted-7-benzyl-2-methyl-5,6,7,8-tetrahydropyrido[4',3':4,5]thieno[2,3-d]pyrimidin-4(3H)-one (7a-k) derivatives were designed and synthesized by using appropriate synthetic protocols. Pantothenate synthetase (PS) was considered as the target for the molecular docking studies and evaluated the binding pattern at active site, as PS plays a significant role in the biosynthesis of pantothenate in Mycobacterium tuberculosis (MTB). The preliminary in vitro antibacterial screening of test compounds was carried out against two strains of Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative (Escherichia coli and Klebsiella pneumoniae) bacteria. The antimycobacterial screening was performed against MTB H37Rv and an isoniazid-resistant clinical isolate of MTB. The compounds 6b, 6c, 6d, 6k, 7b, 7c, 7d and 7k exhibited promising antibacterial activity MIC in the range of 15-73 μM against all bacterial strains used and compounds 6d and 7b showed antimycobacterial activity (IC50 <340 μM in LRP assay) and (MIC <9 μM in broth microdilution method). PMID:26755393

  19. Magnetic-Field-Induced Low-Energy Spin Excitations in YBa2Cu4O8 Measured by High Field Gd3+ Electron Spin Resonance

    NASA Astrophysics Data System (ADS)

    Fehér, Titusz; Jánossy, András; Oszlányi, Gábor; Simon, Ferenc; Dabrowski, Bogdan; Klamut, Piotr W.; Horvatić, Mladen; Williams, Grant V.

    2000-12-01

    We have measured the spin susceptibility, χs, of the CuO2 planes in the underdoped high Tc superconductor, YBa2Cu4O8 by Gd3+ electron spin resonance (ESR) in single crystals and aligned powders in fields up to 15.4 T. At low temperatures and high fields, χs is enhanced slightly in the B∥c orientation with respect to the B⊥c orientation. The enhancement at 15.4 T ( ~0.15Hc2) at 16 K ( 0.2 Tc) is small: approximately 10% of χs\\(Tc\\), suggesting that the second critical field of superconductivity, Hc2~100 T, would not suppress the pseudogap. This work demonstrates the potential of high field ESR in single crystals for studying high Tc superconductors.

  20. 8 CFR 1292.4 - Appearances.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... otherwise provided in § 103.2(b) of 8 CFR chapter I, a party to a proceeding or his attorney or... with § 103.10 of 8 CFR chapter I, obtain copies of Service records or information therefrom and copies... shall be made available for copying or purchase of copies as provided in § 103.10 of 8 CFR chapter I....

  1. 8 CFR 1292.4 - Appearances.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... otherwise provided in § 103.2(b) of 8 CFR chapter I, a party to a proceeding or his attorney or... with § 103.10 of 8 CFR chapter I, obtain copies of Service records or information therefrom and copies... shall be made available for copying or purchase of copies as provided in § 103.10 of 8 CFR chapter I....

  2. Na8Au9.8(4)Ga7.2 and Na17Au15.87(2)Ga46.63: The diversity of pseudo 5-fold 0 Cross Mark symmetries in the Na-Au-Ga system

    SciTech Connect

    Smetana, Volodymyr; Corbett, John D.; Miller, Gordon J.

    2013-08-29

    The Na-rich part (similar to 30% Na) of the Na-Au-Ga system between NaAu2, NaGa4, and Na(22)Ga39 has been found to contain the ternary phases NasAug(8)(4)Ga-7.2 (I) and NavAu(5.87(2))Ga46.63 (II), according to the results of single crystal X-ray diffraction measurements. I is orthorhombic, Cmcm, a= 5.3040(1), b=24.519(5), c=14.573(3) A, and contains a network of clusters with local 5-fold symmetry along the a-axis. Such clusters are frequent building units in decagonal quasicrystals and their approximants. II is rhombohedral, a =16.325(2), c=35.242(7) A, and contains building blocks that are structurally. identical to the Bergman-type clusters as well as fused icosahedral units known with active metals, triels and late transition elements. II also contains a polycationic network with elements of the clathrate V type structure. Tight-binding electronic structure calculations using linear muffin-tin-orbital (LMTO) methods on idealized models of I and II indicate that both compounds are metallic with evident pseudogaps at the corresponding Fermi levels. The overall Hamilton bond populations are generally dominated by Au-Ga and Au-Au bonds in I and by Ga-Ga bonds in II; moreover, the Na-Au and Na-Ga contributions in I are unexpectedly large, 20% of the total. A similar involvement of sodium in covalent bonding has also been found in the electron-richer i-Nai(3)Aui(2)Gai(5) quasicrystal approximant. (C) 2013 Elsevier Inc. All rights reserved.

  3. The thermodynamic properties of 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene. [Tetrahydropyrene and hexahydropyrene

    SciTech Connect

    Chirico, R.D.; Knipmeyer, S.E.; Nguyen, A.; Smith, N.K.; Steele, W.V.

    1992-12-01

    Measurements leading to the calculation of the ideal-gas thermodynamic properties are reported for 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene. Experimental methods included combustion calorimetry, adiabatic heat-capacity calorimetry, vibrating-tube densitometry, comparative ebulliometry, inclined-piston gauge manometry, and differential-scanning calorimetry (d.s.c.). Critical properties were estimated for both materials based on the measurement results. Entropies, enthalpies, and Gibbs energies of formation were derived for the ideal gases for selected temperatures between 380 K and 700 K. The property-measurement results reported here for 4,5,9,10-tetrahydropyrene and 1,2,3,6,7,8-hexahydropyrene are the first for these important intermediates in the pyrene/H[sub 2] hydrogenation reaction network.

  4. Stereoselective Total Synthesis of Atractylodemayne A, a Conjugated 2(E),8(Z),10(E)-Triene-4,6-diyne.

    PubMed

    Schmidt, Bernd; Audörsch, Stephan

    2016-03-01

    The first total synthesis of the polyacetylene natural product atractylodemayne A is reported. Stereoselective construction of the conjugated 8(Z),10(E)-diene moiety was achieved through a tethered ring-closing metathesis approach, comprising a Ru-catalyzed RCM followed by a base-induced elimination. A Pd-catalyzed Cadiot-Chodkiewicz coupling was used for the synthesis of the diyne. Overall, atractylodemayne A was synthesized in nine steps for the longest linear sequence. PMID:26886865

  5. Liquid rocket booster study. Volume 2, book 4, appendices 6-8: Reports of Rocketdyne, Pratt and Whitney, and TRW

    NASA Technical Reports Server (NTRS)

    1988-01-01

    For the pressure fed engines, detailed trade studies were conducted defining engine features such as thrust vector control methods, thrust chamber construction, etc. This was followed by engine design layouts and booster propulsion configuration layouts. For the pump fed engines parametric performance and weight data was generated for both O2/H2 and O2/RP-1 engines. Subsequent studies resulted in the selection of both LOX/RP-1 and O2/H2 propellants for the pump fed engines. More detailed analysis of the selected LOX/RP-1 and O2/H2 engines was conducted during the final phase of the study.

  6. Neolignans with a Rare 2-Oxaspiro[4.5]deca-6,9-dien-8-one Motif from the Stem Bark of Cinnamomum subavenium.

    PubMed

    Lai, Yongji; Liu, Tingting; Sa, Rongjian; Wei, Xialan; Xue, Yongbo; Wu, Zhaodi; Luo, Zengwei; Xiang, Ming; Zhang, Yonghui; Yao, Guangmin

    2015-07-24

    Two pairs of racemic spirodienone neolignans with a rare 2-oxaspiro[4.5]deca-6,9-dien-8-one motif, named (±)-subaveniumins A (1) and B (2), were isolated from the bark of Cinnamomum subavenium. The chiral separation of the (+)-1, (-)-1, (+)-2, and (-)-2 enantiomers was accomplished via high-performance liquid chromatography on a chiral column. Their structures were elucidated using single-crystal X-ray diffraction and spectroscopic analyses (UV, IR, HRESIMS, and 1D and 2D NMR). The absolute configurations of the enantiomers were determined by comparing the experimental and calculated electronic circular dichroic spectra. The (+)-1, (-)-1, (+)-2, and (-)-2 enantiomers exhibited moderate inhibitory effects against NO production in RAW264.7 mouse macrophages induced by lipopolysaccharide, with IC50 values of 17.9, 5.6, 15.1, and 4.3 μM, respectively. PMID:26087384

  7. High-resolution synchrotron X-ray study of the structure of La(1.8)Ba(0.2)CuO(4-y)

    NASA Technical Reports Server (NTRS)

    Moss, S. C.; Forster, K.; Axe, J. D.; You, H.; Hohlwein, D.

    1987-01-01

    X-ray diffraction of La(1.8)Ba(0.2)CuO(4-y) reveals two macroscopically segregated tetragonal (K2NiF4-type) phases of nearly identical lattice parameter. Many peaks show additional broadening upon cooling. This broadening is consistent with a spontaneous monoclinic distortion, with an onset temperature of about 150 K, and is possibly relevant to the superconducting properties. Small single crystals of about 70 micron diameter within the powder aggregate are also studied and show a similar two-phase constituency and a resolvable peak splitting at low temperature.

  8. 8 CFR 217.4 - Inadmissibility and deportability.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Referral to Immigration Judge, for a proceeding in accordance with 8 CFR 208.2(c)(1) and (c)(2). (2) The... in accordance with 8 CFR 208.2(c)(1) and (c)(2). (2) Removal by the district director under paragraph... Section 217.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS VISA...

  9. 8 CFR 217.4 - Inadmissibility and deportability.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Referral to Immigration Judge, for a proceeding in accordance with 8 CFR 208.2(c)(1) and (c)(2). (2) The... in accordance with 8 CFR 208.2(c)(1) and (c)(2). (2) Removal by the district director under paragraph... Section 217.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS VISA...

  10. 8 CFR 217.4 - Inadmissibility and deportability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Referral to Immigration Judge, for a proceeding in accordance with 8 CFR 208.2(c)(1) and (c)(2). (2) The... in accordance with 8 CFR 208.2(c)(1) and (c)(2). (2) Removal by the district director under paragraph... Section 217.4 Aliens and Nationality DEPARTMENT OF HOMELAND SECURITY IMMIGRATION REGULATIONS VISA...

  11. 2,3,4,7,8-Pentachlorodibenzofuran is far less potent than 2,3,7,8-tetrachlorodibenzo-p-dioxin in disrupting the pituitary-gonad axis of the rat fetus.

    PubMed

    Taura, Junki; Takeda, Tomoki; Fujii, Misaki; Hattori, Yukiko; Ishii, Yuji; Kuroki, Hiroaki; Tsukimori, Kiyomi; Uchi, Hiroshi; Furue, Masutaka; Yamada, Hideyuki

    2014-09-16

    The effect of 2,3,4,7,8-pentachlorodibenzofuran (PnCDF) on the fetal pituitary-gonad axis was compared with that produced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in Wistar rats. Maternal treatment at gestational day (GD) 15 with PnCDF and TCDD reduced the fetal expression at GD20 of pituitary luteinizing hormone (LH) and the testicular proteins necessary for steroidogenesis. The relative potencies of PnCDF ranged from 1/42nd to 1/63rd of the TCDD effect. While PnCDF, at a dose sufficient to cause a reduction in fetal LH, provoked defects in sexual behavior at adulthood, a dose less than the ED50 failed to produce any abnormality. There was a loss of fetal body weight following in utero exposure to PnCDF, and the effect of PnCDF was also much less than that of TCDD. The disturbance in fetal growth was suggested to be due to a reduction in the level of fetal growth hormone (GH) by dioxins. The disorder caused by PnCDF/TCDD in the fetal pituitary-gonad axis occurred at doses less than those needed to cause wasting syndrome in pubertal rats. The harmful effect of PnCDF relative to TCDD was more pronounced in fetal rats than in pubertal rats. These lines of evidence suggest that: 1) PnCDF as well as TCDD imprints defects in sexual behavior by disrupting the fetal pituitary-gonad axis; 2) these dioxins hinder fetal growth by reducing the expression of fetal GH; and 3) the fetal effects of PnCDF/TCDD are more sensitive than sub-acute toxicity during puberty, and the relative effect of PnCDF varies markedly depending on the indices used. PMID:25220434

  12. Manganese/cerium clusters spanning a range of oxidation levels and CeMn(8), Ce(2)Mn(4), and Ce(6)Mn(4) nuclearities: structural, magnetic, and EPR properties.

    PubMed

    Lampropoulos, Christos; Thuijs, Annaliese E; Mitchell, Kylie J; Abboud, Khalil A; Christou, George

    2014-07-01

    The syntheses, structures, and magnetic properties are reported for three new Ce/Mn clusters with different Ce/Mn ratios: [Ce6Mn4O12(O2CMe)10(NO3)4(py)4] (py = pyridine) (1), [CeMn8O8(O2CCH2(t)Bu)12(DMF)14] (DMF = dimethylformamide) (2), and [Ce2Mn4O2(O2CMe)6(NO3)4(hmp)4] (3; hmp(-) is the anion of 2-(hydroxymethyl)pyridine). 1 and 2 were obtained from the reaction of Ce(IV) with [Mn12O12(O2CMe)16(H2O)4] (Mn(III)8Mn(IV)4) and [Mn8O2(O2CCH2(t)Bu)14((t)BuCH2CO2H)4] (Mn(II)6Mn(III)2), respectively, whereas 3 resulted from the oxidation of Mn(II) acetate with Ce(IV) in the presence of hmpH. Cluster 1 possesses an unusual [Ce6Mn4O12](14+) core topology consisting of a [Ce6O8] face-capped octahedron, which is face-fused at each end to a [Ce(IV)2Mn(III)Mn(IV)O4] cubane. Cluster 2 possesses a nonplanar, saddlelike loop of eight Mn(III) atoms bridged by eight μ3-O(2-) ions to a central Ce(IV) atom. Cluster 3 is similar to 1 in possessing an octahedral core, but this is now a [Ce2Mn4] octahedron consisting of a Ce(III) atom on either side of a Mn4 parallelogram, with the metal atoms bridged by two μ4-O(2-) ions, the alkoxide arms of four hmp(-) groups, and six acetates. Clusters 1, 2, and 3 are thus at the Ce(IV)6Mn(III)2Mn(IV)2, Ce(IV)Mn(III)8, and Ce(III)2Mn(III)4 oxidation levels, respectively. Variable-temperature, solid-state direct current (DC) and alternating current (AC) magnetization studies on 1-3 in the 5.0-300 K range revealed predominantly antiferromagnetic exchange interactions within the complexes. For 1, fitting of the DC data to the theoretical expression for a dinuclear Mn(III)Mn(IV) complex derived using the Van Vleck equation and an isotropic spin Hamiltonian (ℋ = -2JŜi·Ŝj convention) gave a value for the exchange coupling parameter (J) of -60.4(7) cm(-1) and a Landé factor g = 2.00(1), indicating an S = 1/2 ground state. For 2, both DC and AC data indicate an S = 0 ground state, which is unprecedented for a member of the CeMn8 family and now

  13. Non-additive hepatic gene expression elicited by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153) co-treatment in C57BL/6 mice

    SciTech Connect

    Kopec, Anna K.; D'Souza, Michelle L.; Mets, Bryan D.; Burgoon, Lyle D.; Reese, Sarah E.; Archer, Kellie J.; Potter, Dave; Tashiro, Colleen; Sharratt, Bonnie; Harkema, Jack R.; Zacharewski, Timothy R.

    2011-10-15

    Interactions between environmental contaminants can lead to non-additive effects that may affect the toxicity and risk assessment of a mixture. Comprehensive time course and dose-response studies with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), non-dioxin-like 2,2',4,4',5,5'-hexachlorobiphenyl (PCB153) and their mixture were performed in immature, ovariectomized C57BL/6 mice. Mice were gavaged once with 30 {mu}g/kg TCDD, 300 mg/kg PCB153, a mixture of 30 {mu}g/kg TCDD with 300 mg/kg PCB153 (MIX) or sesame oil vehicle for 4,12, 24,72 or 168 h. In the 24 h dose-response study, animals were gavaged with TCDD (0.3,1, 3, 6, 10, 15, 30, 45 {mu}g/kg), PCB153 (3,10, 30, 60, 100, 150, 300, 450 mg/kg), MIX (0.3 + 3, 1 + 10, 3 + 30, 6 + 60, 10 + 100, 15 + 150, 30 + 300, 45 {mu}g/kg TCDD + 450 mg/kg PCB153, respectively) or vehicle. All three treatments significantly increased relative liver weights (RLW), with MIX eliciting significantly greater increases compared to TCDD and PCB153 alone. Histologically, MIX induced hepatocellular hypertrophy, vacuolization, inflammation, hyperplasia and necrosis, a combination of TCDD and PCB153 responses. Complementary lipid analyses identified significant increases in hepatic triglycerides in MIX and TCDD samples, while PCB153 had no effect on lipids. Hepatic PCB153 levels were also significantly increased with TCDD co-treatment. Microarray analysis identified 167 TCDD, 185 PCB153 and 388 MIX unique differentially expressed genes. Statistical modeling of quantitative real-time PCR analysis of Pla2g12a, Serpinb6a, Nqo1, Srxn1, and Dysf verified non-additive expression following MIX treatment compared to TCDD and PCB153 alone. In summary, TCDD and PCB153 co-treatment elicited specific non-additive gene expression effects that are consistent with RLW increases, histopathology, and hepatic lipid accumulation. - Graphical abstract: Display Omitted Highlights: > MIX (TCDD:PCB153 at 1:10,000 ratio) exposure leads to non-additive gene expression

  14. Novel Highly Pathogenic Avian A(H5N2) and A(H5N8) Influenza Viruses of Clade 2.3.4.4 from North America Have Limited Capacity for Replication and Transmission in Mammals

    PubMed Central

    Kaplan, Bryan S.; Russier, Marion; Jeevan, Trushar; Marathe, Bindumadhav; Govorkova, Elena A.; Russell, Charles J.; Kim-Torchetti, Mia; Choi, Young Ki; Brown, Ian; Saito, Takehiko; Stallknecht, David E.; Krauss, Scott

    2016-01-01

    ABSTRACT Highly pathogenic influenza A(H5N8) viruses from clade 2.3.4.4 were introduced to North America by migratory birds in the fall of 2014. Reassortment of A(H5N8) viruses with avian viruses of North American lineage resulted in the generation of novel A(H5N2) viruses with novel genotypes. Through sequencing of recent avian influenza viruses, we identified PB1 and NP gene segments very similar to those in the viruses isolated from North American waterfowl prior to the introduction of A(H5N8) to North America, highlighting these bird species in the origin of reassortant A(H5N2) viruses. While they were highly virulent and transmissible in poultry, we found A(H5N2) viruses to be low pathogenic in mice and ferrets, and replication was limited in both hosts compared with those of recent highly pathogenic avian influenza (HPAI) H5N1 viruses. Molecular characterization of the hemagglutinin protein from A(H5N2) viruses showed that the receptor binding preference, cleavage, and pH of activation were highly adapted for replication in avian species and similar to those of other 2.3.4.4 viruses. In addition, North American and Eurasian clade 2.3.4.4 H5NX viruses replicated to significantly lower titers in differentiated normal human bronchial epithelial cells than did seasonal human A(H1N1) and highly pathogenic A(H5N1) viruses isolated from a human case. Thus, despite their having a high impact on poultry, our findings suggest that the recently emerging North American A(H5N2) viruses are not expected to pose a substantial threat to humans and other mammals without further reassortment and/or adaptation and that reassortment with North American viruses has not had a major impact on viral phenotype. IMPORTANCE Highly pathogenic H5 influenza viruses have been introduced into North America from Asia, causing extensive morbidity and mortality in domestic poultry. The introduced viruses have reassorted with North American avian influenza viruses, generating viral genotypes

  15. Novel Highly Pathogenic Avian A(H5N2) and A(H5N8) Influenza Viruses of Clade 2.3.4.4 from North America Have Limited Capacity for Replication and Transmission in Mammals.

    PubMed

    Kaplan, Bryan S; Russier, Marion; Jeevan, Trushar; Marathe, Bindumadhav; Govorkova, Elena A; Russell, Charles J; Kim-Torchetti, Mia; Choi, Young Ki; Brown, Ian; Saito, Takehiko; Stallknecht, David E; Krauss, Scott; Webby, Richard J

    2016-01-01

    Highly pathogenic influenza A(H5N8) viruses from clade 2.3.4.4 were introduced to North America by migratory birds in the fall of 2014. Reassortment of A(H5N8) viruses with avian viruses of North American lineage resulted in the generation of novel A(H5N2) viruses with novel genotypes. Through sequencing of recent avian influenza viruses, we identified PB1 and NP gene segments very similar to those in the viruses isolated from North American waterfowl prior to the introduction of A(H5N8) to North America, highlighting these bird species in the origin of reassortant A(H5N2) viruses. While they were highly virulent and transmissible in poultry, we found A(H5N2) viruses to be low pathogenic in mice and ferrets, and replication was limited in both hosts compared with those of recent highly pathogenic avian influenza (HPAI) H5N1 viruses. Molecular characterization of the hemagglutinin protein from A(H5N2) viruses showed that the receptor binding preference, cleavage, and pH of activation were highly adapted for replication in avian species and similar to those of other 2.3.4.4 viruses. In addition, North American and Eurasian clade 2.3.4.4 H5NX viruses replicated to significantly lower titers in differentiated normal human bronchial epithelial cells than did seasonal human A(H1N1) and highly pathogenic A(H5N1) viruses isolated from a human case. Thus, despite their having a high impact on poultry, our findings suggest that the recently emerging North American A(H5N2) viruses are not expected to pose a substantial threat to humans and other mammals without further reassortment and/or adaptation and that reassortment with North American viruses has not had a major impact on viral phenotype. IMPORTANCE Highly pathogenic H5 influenza viruses have been introduced into North America from Asia, causing extensive morbidity and mortality in domestic poultry. The introduced viruses have reassorted with North American avian influenza viruses, generating viral genotypes not seen on

  16. Magnetic and electrical properties of (FeIn2S4)1-x(CuIn5S8)x solid solutions

    NASA Astrophysics Data System (ADS)

    Trukhanov, S. V.; Bodnar, I. V.; Zhafar, M. A.

    2015-04-01

    In this study, single crystals of FeIn2S4 and CuIn5S8 compounds, and (FeIn2S4)1-x(CuIn5S8)x solid solutions were grown using the Bridgman method. The magnetic and electrical properties of the samples obtained were investigated at temperatures of 5-300 K and in a magnetic field range of 0-14 T. It was established that all of the solid solutions were paramagnets down to low temperatures of ~10 K. It was shown that the ground state of the magnetic phase of the samples was a spin glass state, where the freezing temperature increased monotonically with the increase in the concentration of Fe2+ cations. All of the samples exhibited semiconductor characteristics in terms of electrical resistivity. The concentration-dependent critical magnetic temperatures, magnetic moment, and activation energy were plotted, which are probably explained by the magnetic state formation of the (FeIn2S4)1-x(CuIn5S8)x solid solution single crystals based on the empirical Goodenough-Kanamori rules.

  17. Composite cathode La0.4Sr0.4TiO3-δ-Ce0.8Sm0.2O2-δ impregnated with Ni for high-temperature steam electrolysis

    NASA Astrophysics Data System (ADS)

    Gan, Yun; Qin, Qingqing; Chen, Shigang; Wang, Yan; Dong, Dehua; Xie, Kui; Wu, Yucheng

    2014-01-01

    Composite Ni-SDC (Samaria doped Ceria) cathodes are able to operate in strong reducing atmospheres for steam electrolysis, and composite cathodes based on redox-stable La0.4Sr0.4TiO3 (LSTO) have demonstrated promising performances without the reducing gas flow. However, the electro-catalytic activity of cathodes based on LSTO is insufficient for the efficient electrochemical reduction of steam or carbon oxide. In this work, catalytic-active Ni nanoparticles were loaded on a La0.4Sr0.4TiO3-δ-Ce0.8Sm0.2O2-δ cathode (Ni-loaded LSTO-SDC) via an impregnation method to improve the electrode performances for direct steam electrolysis. The synergetic effect of catalytically-active Ni nanoparticles and the redox-stable LSTO-SDC skeleton contributed to the improved performances and the excellent stability of the cathode for direct steam electrolysis. The current efficiency with a Ni-loaded cathode was enhanced by 3% and 17% compared to the values with a bare LSTO-SDC cathode under 2.0 V of applied voltage at 800 °C with a flow of 3% H2O/5% H2/Ar and 3% H2O/Ar to cathodes, respectively.

  18. Hydrothermal synthesis, crystal structure, and magnetic properties of a novel organo-templated iron(III) borophosphate: (C{sub 3}H{sub 12}N{sub 2})Fe{sup III} {sub 6}(H{sub 2}O){sub 4}[B{sub 4}P{sub 8}O{sub 32}(OH){sub 8}

    SciTech Connect

    Huang Yaxi; Schnelle, Walter; Zhang Hui; Borrmann, Horst; Kniep, Ruediger

    2009-04-15

    The organo-templated iron(III) borophosphate (C{sub 3}H{sub 12}N{sub 2})Fe{sup III} {sub 6}(H{sub 2}O){sub 4}[B{sub 4}P{sub 8}O{sub 32}(OH){sub 8}] was prepared under mild hydrothermal conditions (at 443 K) and the crystal structure was determined from single crystal X-ray data at 295 K (monoclinic, P2{sub 1}/c (No. 14), a=5.014(2) A, b=9.309(2) A, c=20.923(7) A, beta=110.29(2){sup o}, V=915.9(5) A{sup 3}, Z=2, R1=0.049, wR2=0.107 for all data, 2234 observed reflections with I>2sigma(I)). The title compound contains a complex inorganic framework of borophosphate trimers [BP{sub 2}O{sub 8}(OH){sub 2}]{sup 5-} together with FeO{sub 4}(OH)(H{sub 2}O)- and FeO{sub 4}(OH){sub 2}-octahedra forming channels with ten-membered ring apertures in which the diaminopropane cations are located. The magnetization measurements confirm the Fe(III)-state and show an antiferromagnetic ordering at T{sub N}{approx}14.0(1) K. - Graphical abstract: The complex inorganic open-framework of (C{sub 3}H{sub 12}N{sub 2})Fe{sup III} {sub 6}(H{sub 2}O){sub 4}[B{sub 4}P{sub 8}O{sub 32}(OH){sub 8}] consists of borophosphate trimers and iron(III) coordination octahedra arranged to form channels with ten-membered ring apertures in which the organic 1,3-diaminopropane cations are located.

  19. Triggering TLR2, -3, -4, -5, and -8 Reinforces the Restrictive Nature of M1- and M2-Polarized Macrophages to HIV

    PubMed Central

    Schlaepfer, Erika; Rochat, Mary-Aude; Duo, Li

    2014-01-01

    ABSTRACT Macrophages must react to a large number of pathogens and their effects. In chronic HIV infection, the microenvironment changes with an influx of microbial products that trigger Toll-like receptors (TLRs). That dynamic nature can be replicated ex vivo by the proinflammatory (M1-polarized) and alternatively activated (M2-polarized) macrophages. Thus, we determined how polarized macrophages primed by various TLR agonists support HIV replication. Triggering of TLR2, -3, -4, -5, and -8 reinforced the low level of permissiveness in polarized macrophages. HIV was inhibited even more in M1-polarized macrophages than in macrophages activated only by TLR agonists. HIV was inhibited before its integration into the host chromosome. Polarization and triggering by various TLR agonists resulted in distinct cytokine profiles, endocytic activity, and distinct upregulation of restriction factors of HIV. Thus, different mechanisms likely contribute to the HIV-inhibitory effects. In chronic HIV infection, macrophages might become less permissive to HIV due to changes in the microenvironment. The high level of reactivity of polarized macrophages to TLR triggering may be exploited for immunotherapeutic strategies. IMPORTANCE Macrophages are a major target of HIV-1 infection. Different cell types in this very heterogeneous cell population respond differently to stimuli. In vitro, the heterogeneity is mimicked by their polarization into proinflammatory and alternatively activated macrophages. Here we explored the extent to which agonists triggering the TLR family affect HIV replication in polarized macrophages. We found that a number of TLR agonists blocked HIV replication substantially when given before infection. We also report the mechanisms of how TLR agonists exert their inhibitory action. Our findings may advance our understanding of which and how TLR agonists block HIV infection in polarized macrophages and may facilitate the design of novel immunotherapeutic approaches

  20. Synthesis, crystal structure and magnetic properties of a new copper oxo-antimony sulphate CuSb6O8(SO4)2.

    PubMed

    Zimmermann, Iwan; Kremer, Reinhard K; Hu, Shichao; Johnsson, Mats

    2016-01-01

    The new copper oxo-antimony sulphate CuSb6O8(SO4)2 crystallizes in the triclinic space group P1[combining macron] with the unit cell parameters a = 5.5342(4) Å, b = 7.6706(6) Å, c = 9.2374(7) Å, α = 96.505(5)°, β = 93.818(4)°, γ = 109.733(4)° and Z = 1. The crystal structure is made up of layers stacking along [001]. The layers are charge neutral and are connected to each other by only weak interactions. The copper atoms adopt a square planar [CuO4] coordination and such units are well separated from each other by corner and edge sharing to [SbO4] building blocks. The latter polymerize to form sheets with the formula [Sb3O8]∞. Sulphate groups connect to the antimony oxide sheets by corner sharing and are located at the interface of the layers. Above ∼10 K the magnetic susceptibility follows very well a Curie-Weiss law whereas below 10 K increasing deviations indicate the onset of antiferromagnetic correlations. Fitting the data in the range 10-50 K yields a Curie-Weiss temperature θ of -2.25(5) K. A sharp anomaly centered at TC = 0.67 K in the heat capacity data indicates long-range magnetic ordering. Short range antiferromagnetic correlations well above TC are seen in the magnetic contribution to the heat capacity and the magnetic susceptibility. These can be well described by the magnetism of a spin S = 1/2 Heisenberg chain with the nearest neighbor antiferromagnetic spin exchange interaction of Jintra = ∼2.8 K. PMID:26619936

  1. 4-Amino-2,8-dimethyl-6H-pyrimido[1,2-a][1,3,5]triazin-6-one1

    PubMed Central

    Sachdeva, Nikhil; Dolzhenko, Anton V.; Tan, Geok Kheng; Koh, Lip Lin; Chui, Wai Keung

    2010-01-01

    In the title compound, C8H9N5O, the mean planes through the pyrimidine and triazine rings form a dihedral angle of 2.83 (16)°. The amino group adopts a trigonal-planar configuration and forms an intra­molecular resonance-assisted N—H⋯O=C hydrogen bond with the carbonyl group. In the crystal, mol­ecules are linked via inter­molecular N—H⋯N hydrogen bonds into chains of C 2 2(6)[R 2 2(6)] motif. The molecules form two types of sheet parallel to (201) and (01), respectively. PMID:21588357

  2. A versatile photoacoustic spectrometer for sensitive trace-gas analysis in the mid-infrared wavelength region (5.1-8.0 and 2.8-4.1 μm)

    NASA Astrophysics Data System (ADS)

    Persijn, S. T.; Santosa, E.; Harren, F. J. M.

    A versatile CO laser-based photoacoustic spectrometer is presented equipped with three photoacoustic cells placed inside the laser cavity. The newly designed CO laser can operate both in the Δv=1 and the Δv=2 modes (5.1-8.0 μm and 2.8-4.1 μm) on 400 laser lines. Improved laser operation originating from a better cooling of the gas discharge was evidenced by a shift of the laser output power to lower J-values. Due to the wide emission range of the source, many molecules of biological and atmospheric interest, including methane and ethane, can be detected with sensitivities typically at the (sub)ppb level. Measurement of the respiration of a cockroach showed that the spectrometer is not only sensitive, but also has a good time response (8 s at a flow rate of 10 l/h).

  3. 8 CFR 1245.4 - Documentary requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Documentary requirements. 1245.4 Section 1245.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE... Documentary requirements. The provisions of part 1211 of this chapter relating to the documentary...

  4. 8 CFR 245.4 - Documentary requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Documentary requirements. 245.4 Section 245... STATUS TO THAT OF PERSON ADMITTED FOR PERMANENT RESIDENCE § 245.4 Documentary requirements. The provisions of part 211 of this chapter relating to the documentary requirements for immigrants shall...

  5. 8 CFR 245.4 - Documentary requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 8 Aliens and Nationality 1 2011-01-01 2011-01-01 false Documentary requirements. 245.4 Section 245... STATUS TO THAT OF PERSON ADMITTED FOR PERMANENT RESIDENCE § 245.4 Documentary requirements. The provisions of part 211 of this chapter relating to the documentary requirements for immigrants shall...

  6. 8 CFR 1245.4 - Documentary requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Documentary requirements. 1245.4 Section 1245.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE... Documentary requirements. The provisions of part 1211 of this chapter relating to the documentary...

  7. 8 CFR 1245.4 - Documentary requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Documentary requirements. 1245.4 Section 1245.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE... Documentary requirements. The provisions of part 1211 of this chapter relating to the documentary...

  8. 8 CFR 1245.4 - Documentary requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Documentary requirements. 1245.4 Section 1245.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE... Documentary requirements. The provisions of part 1211 of this chapter relating to the documentary...

  9. 8 CFR 1245.4 - Documentary requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Documentary requirements. 1245.4 Section 1245.4 Aliens and Nationality EXECUTIVE OFFICE FOR IMMIGRATION REVIEW, DEPARTMENT OF JUSTICE... Documentary requirements. The provisions of part 1211 of this chapter relating to the documentary...

  10. 8 CFR 245.4 - Documentary requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 8 Aliens and Nationality 1 2013-01-01 2013-01-01 false Documentary requirements. 245.4 Section 245... STATUS TO THAT OF PERSON ADMITTED FOR PERMANENT RESIDENCE § 245.4 Documentary requirements. The provisions of part 211 of this chapter relating to the documentary requirements for immigrants shall...

  11. 8 CFR 245.4 - Documentary requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 8 Aliens and Nationality 1 2014-01-01 2014-01-01 false Documentary requirements. 245.4 Section 245... STATUS TO THAT OF PERSON ADMITTED FOR PERMANENT RESIDENCE § 245.4 Documentary requirements. The provisions of part 211 of this chapter relating to the documentary requirements for immigrants shall...

  12. 8 CFR 245.4 - Documentary requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 8 Aliens and Nationality 1 2012-01-01 2012-01-01 false Documentary requirements. 245.4 Section 245... STATUS TO THAT OF PERSON ADMITTED FOR PERMANENT RESIDENCE § 245.4 Documentary requirements. The provisions of part 211 of this chapter relating to the documentary requirements for immigrants shall...

  13. Synthesis, structural elucidation and spectroscopic analysis of 3a,8b-dihydroxy-4-oxo-1H,2H,3H,3aH,4H,8bH-indeno[1,2-d]imidazolidin-2-iminium chloride

    NASA Astrophysics Data System (ADS)

    Uma Devi, T.; Priya, S.; Selvanayagam, S.; Ravikumar, K.; Anitha, K.

    2012-11-01

    Ninhydrin guanidinium chloride (3a,8b-dihydroxy-4-oxo-1H,2H,3H,3aH,4H,8bH-indeno [1,2-d]imidazolidin-2-iminium chloride) a semiorganic crystal was synthesized. The structure was determined using X-ray single crystal technique. Comparisons between the FT-IR spectrum of ninhydrin guanidinium chloride with ninhydrin were made. Melting point was found using thermal measurements. The molecular geometry, vibrational frequencies and Mulliken charges of the compound in the ground state have been calculated by the density functional theory (DFT) method with 3-21G(d,p) basis set and theoretical frequencies were compared with the experimental FT-IR spectrum. Besides, molecular electrostatic potential (MEP), frontier molecular orbitals (FMO) analysis, natural bond orbitals (NBO) and thermodynamic properties at various temperatures of the compound were investigated by theoretical calculations.

  14. Hyperfine structure of the 4{f}^{8}5{d}^{2}6s configuration in the Tb atom

    NASA Astrophysics Data System (ADS)

    Furmann, B.; Stefanska, D.; Krzykowski, A.

    2016-01-01

    Within this work new experimental results concerning the hyperfine structure (hfs) in the terbium atom are presented. Hfs constants A and B for eight levels belonging to the even-parity configuration 4{f}85{d}26s were determined, based on the results of measurements performed using the laser-induced fluorescence method in a hollow cathode discharge at 18 spectral lines. The configuration 4{f}85{d}26s in the terbium atom was hitherto very scarcely investigated; for seven of the levels examined within this work results concerning the hfs were obtained for the first time. As a by-product, hfs constants for 12 odd-parity levels, involved as upper levels in the transitions investigated, were also determined. A preliminary attempt at a semi-empirical analysis of Tb I hfs on a multi-configuration basis, based on the results of this work, yielded a value of the one-electron {a}6s10 parameter as well as the respective radial integral {< {r}-3> }6s10, which can be compared with the values along the lanthanide elements series reported in the literature. More conclusive results can certainly be obtained once the experimental database for Tb I becomes more extensive.

  15. Verification of the Major Metabolic Oxidation Path for the Naphthoyl Group in Chemoattractant Receptor-Homologous Molecule Expressed on Th2 Cells (CRTh2) Antagonist 2-(2-(1-Naphthoyl)-8-fluoro-3,4-dihydro-1H-pyrido[4,3-b]indol-5(2H)-yl)acetic Acid (Setipiprant/ACT-129968).

    PubMed

    Risch, Philippe; Pfeifer, Thomas; Segrestaa, Jerome; Fretz, Heinz; Pothier, Julien

    2015-10-22

    Various racemic and enantioenriched (trans)-X,Y-dihydroxy-X,Y-dihydronaphthoyl analogues as well as X-hydroxy-naphthoyl analogues of CRTh2 antagonist 2-(2-(1-naphthoyl)-8-fluoro-3,4-dihydro-1H-pyrido[4,3-b]indol-5(2H)-yl)acetic acid (1, Setipiprant/ACT-129968) were synthesized in order to gain insight into regio- and enantioselectivity of the metabolic oxidation of 1 and to verify the structures of four metabolites that were proposed earlier in a clinical ADME study. Analytical data of the synthetic standards were compared with data from samples of biological origin. The two major metabolites M7 and M9 were unambiguously verified as 2-(2-((trans)-3,4-dihydroxy-3,4-dihydronaphthalene-1-carbonyl)- and 2-(2-((trans)-5,6-dihydroxy-5,6-dihydronaphthalene-1-carbonyl)-8-fluoro-3,4-dihydro-1H-pyrido[4,3-b]indol-5(2H)-yl)acetic acid, respectively, each composed of two enantiomers with 68% and 44% ee in favor of (+)-(3S,4S)-M7 and (+)-(5S,6S)-M9, respectively. Likewise, minor metabolites M3 and M13 were identified as 2-(8-fluoro-2-(5-hydroxy-1-naphthoyl)- and 2-(8-fluoro-2-(4-hydroxy-1-naphthoyl)-1,2,3,4-tetrahydro-5H-pyrido[4,3-b]indol-5-yl)acetic acid, respectively. PMID:26398218

  16. Crystallinity and in-field characterization of high-Tc YBa2Cu408 and Y0.9Ca0.1Ba2Cu4O8 epitaxial films fabricated by low temperature flux method

    NASA Astrophysics Data System (ADS)

    Funaki, S.; Yamada, Y.; Nakayama, F.

    2014-05-01

    REBa2Cu4O8 superconductor has an important advantage that the critical temperature (Tc) is improved by Ca substitution for RE site. We fabricated the YBa2Cu4O8 (Y124) and Y0.9Ca0.1Ba2Cu4O8 (YCa124) films by molten hydroxide method in ambient atmosphere and investigated the crystallinity and in-field characterization. Obtained samples show that the film alignment is biaxial orientation and the grain size is larger than 50 μm, and the irreversibility field of YCa124 film is superior to that of Y124 in all the measured magnetic fields

  17. 8-Methly-4-(3-diethylaminopropylamino) pyrimido [4',5';4,5] thieno (2,3-b) quinoline (MDPTQ), a quinoline derivate that causes ROS-mediated apoptosis in leukemia cell lines

    SciTech Connect

    Shenoy, Sudheer; Vasania, Viraf S.; Gopal, M.; Mehta, Ashish . E-mail: ashish_mehta@relbio.com

    2007-07-01

    The present study reports the biological activity of 8-methly-4-(3-diethylamino-propylamino) pyrimido [4';5';4,5] thieno (2,3-b) quinoline (MDPTQ), a quinoline derivative structurally related to ellipticine and suggests a possible mechanism through which the compound induces apoptosis in carcinoma cell lines. Out of the 8 cell lines used in the study as representatives of different types of cancer, MDPTQ was found to be effective only against leukemia cell lines (HL-60 and K-562) whereas it had no effect on normal human bone marrow cells (BMC) which were used as controls. Fall mitochondrial membrane potential and increased reactive oxygen species (ROS) were mainly responsible for inducing apoptosis in the two cell lines. Cell death was demonstrated by increase in caspase 3 activity as well as phosphatidyl serine exposure. Pre-incubation with N-acetylcysteine (NAC) reduced the increased ROS and caspase 3 activity as well as phosphatidyl serine exposure. MDPTQ also caused cell cycle arrest in these cell lines. The above study for the first time reports the mode of action of a quinoline derivative, which could be a possible future candidate for leukemia therapy. However, there are lot of questions that need to be answered in terms of signalling pathways and its effects on animal models.

  18. 4-(4-Bromo­phen­yl)-8-methyl-2-oxo-1,2,3,4,4a,5,6,7-octa­hydro­quinoline-3-carbonitrile

    PubMed Central

    Asiri, Abdullah M.; Faidallah, Hassan M.; Ng, Seik Weng; Tiekink, Edward R. T.

    2012-01-01

    In the title compound, C17H17BrN2O, the N-containing ring adopts an envelope conformation with the C atom carrying the phenyl ring displaced by −0.531 (9) Å from the plane defined by the remaining five atoms (r.m.s. deviation = 0.0099 Å). The benzene ring is almost orthogonal to the ring to which it is attached, the CCN—C—CPh—CPh torsion angle being −101.3 (7)°. The cyclo­hexene ring is disordered over two conformations in a statistical ratio. The most prominent inter­actions in the crystal are pairs of N—H⋯O hydrogen bonds between inversion-related mol­ecules. The resulting dimers are linked into a three-dimensional architecture by C—H⋯N, C—H⋯Br and C—H⋯π inter­actions. PMID:22904838

  19. Thermochemistry and dissociation dynamics of state-selected C/sub 4/H/sub 8/O/sub 2//sup +/ ions. 3. Ethyl acetate

    SciTech Connect

    Fraser-Monteiro, L.; Fraser-Monteiro, M.L.; Butler, J.J.; Baer, T.

    1982-01-01

    The photoionization efficiency curves and appearance energies of C/sub 4/H/sub 8/O/sub 2//sup +/, C/sub 3/H/sub 5/O/sub 2//sup +/, C/sub 4/H/sub 6/O/sup +/, C/sub 2/H/sub 5/O/sub 2//sup +/, C/sub 2/H/sub 5/O/sup +/, C/sub 2/H/sub 3/O/sup +/, and C/sub 2/H/sub 5//sup +/ from ethyl acetate have been obtained. Structures and heats of formation of some of the ions are proposed. The ethyl acetate ion was found to be metastable in the vicinity of the first dissociation onset producing C/sub 4/H/sub 6/O/sup +/ (m/e 70) and H/sub 2/O. The decay rates as a function of parent ion internal energy were measured betwen 10.4 and 10.7 eV. The comparison of the observed rates with those calculated by use of the RRKM/QET statistical theory indicates that the the ethyl acetate ion isomerizes to a more stable ion prior to dissociation. The isomerized structure is neither that of dioxane nor butanoic acid, but may be the enol tautomer of ethyl acetate.

  20. Studies of (Cs,Ba)-hollandite dissolution under gamma irradiation at 95 °C and at pH 2.5, 4.4 and 8.6

    NASA Astrophysics Data System (ADS)

    Suzuki-Muresan, T.; Vandenborre, J.; Abdelouas, A.; Grambow, B.; Utsunomiya, S.

    2011-12-01

    In the frame of the former French 1991-law on waste management, which was extended in 2006-law, hollandite ceramic was studied as a potential specific conditioning matrix for caesium isotopes (long-life radionuclide 135Cs and the strong heat generating radionuclide 137Cs). In this general study of Cs-containment in a ceramic matrix, the chemical durability was pointed out as a key property. Leaching experiments in static mode were conducted during 240 days at various pH-values from acidic to alkaline range. The initial leaching rates between 0 and 45 days are faster for Cs than for Ba and the average for the caesium are (1.4 ± 0.1) × 10 -4 g/m 2/d (pH 2.5), (6.4 ± 0.9) × 10 -5 g/m 2/d (pH 4.4) and (3.1 ± 0.6) × 10 -5 g/m 2/d (pH 8.6), and for the barium (6 ± 1) × 10 -5 g/m 2/d (pH 2.5), (2.8 ± 0.3) × 10 -5 g/m 2/d (pH 4.4), and (2 ± 2) × 10 -6 g/m 2/d (pH 8.6). At the equilibrium between 45 and 240 days, the normalised mass losses average for caesium are (8.2 ± 0.3) × 10 -3 g/m 2 (pH 2.5), (5.2 ± 0.4) × 10 -3 g/m 2 (pH 4.4) and (4.1 ± 0.2) × 10 -3 g/m 2 (pH 8.6), and for barium (3.7 ± 0.4) × 10 -3 g/m 2 (pH 2.5), (2.0 ± 0.1) × 10 -3 g/m 2 (pH 4.4) and (4 ± 2) × 10 -4 g/m 2 (pH 8.6). Caesium and barium are incongruently released in solution with a correlation slope close to 0.5 at pH 2.5 and pH 4.4 and very low (near 0.02) in alkaline solution. Sorption experiments with radioactive isotopes ( 137Cs and 133Ba) were conducted on hollandite pre-leached in aqueous solutions. Caesium and barium release is controlled by the surface reactions. Leaching experiments and isotopic addition experiments ( 137Cs- and 133Ba-radiotracer) indicate that caesium behaviour is independent on pH-values, whereas barium behaviour is strongly dependent. Additional experiments in the presence of gamma irradiation ( 60Co source) did not show any significant effect on hollandite leaching process.

  1. HPLC separation and FT-IR isomer differentiation of the 1,2,4,7/1,2,4,8-tetrachlorodibenzodioxin isomer pair: A theoretical/empirical approach to dibenzodioxin isomer assignmentt

    SciTech Connect

    Grainger, J.; Barnhart, E.; Patterson D.G. Jr.; Presser, D.

    1988-02-01

    The 1,2,4,7-and 1,2,4,8-tetrachlorodibenzodioxin (TCDD) isomers were separated by reversed-phase high-performance liquid chromatography (HPLC) with the use of a pyrene column. Fourier transform infrared (FT-IR) matrix isolation and vapor-phase spectra of the individual isomers were recorded. The spectra of the HPLC-seprated isomers correlate well with spectral subtraction results and were found to be distinct in three spectral regions: one of which allows for isomer structural assignment. Ambiguities and differences in published TCDD isomer FT-IR assignments are discussed in terms of a qualitative valence-bond approach and empirically derived estimates of ether linkage asymmetric stretching frequencies.

  2. Reactions of 7,8-dithiabicyclo[4.2.1]nona-2,4-diene 7-exo-oxide with dodecacarbonyl triiron Fe3(CO)12: a novel type of sulfenato thiolato diiron hexacarbonyl complexes.

    PubMed

    Windhager, Jochen; Apfel, Ulf-Peter; Yoshino, Tomoharu; Nakata, Norio; Görls, Helmar; Rudolph, Manfred; Ishii, Akihiko; Weigand, Wolfgang

    2010-07-01

    The reaction of Fe(3)(CO)(12) (13) with 7,8-dithiabicyclo[4.2.1]nona-2,4-diene 7-exo-oxide (12) yields the sulfenato-thiolato complex 14, which is used as starting material for further reactions. The disulfenato complex 17 is obtained by using one equivalent of dimethyldioxirane (DMD), and the monoepoxide 18 is prepared by the oxidation of 14 with an excess of DMD. Complex 14 can be converted to the monophosphine complexes 19a and 19b by subsequent substitution of one CO ligand using trimethylaminoxide Me(3)NO and triphenylphosphine PPh(3). Additional substitution reactions are done with 17 by using acetonitrile as a ligand to form 20a and 20b. In the electrochemical part of the paper, the reactions of the reduced iron species 14, 15, 17, and 19a are studied. PMID:20473980

  3. Anticonvulsant Activity of Schiff Bases of 3-Amino-6,8-dibromo-2-phenyl-quinazolin-4(3H)-ones

    PubMed Central

    Paneersalvam, P.; Raj, T.; Ishar, M. P. S.; Singh, B.; Sharma, V.; Rather, B. A.

    2010-01-01

    Schiff bases (9a-l) of 3-amino-6,8-dibromo-2-phenyl-quinazolin-4-(3H)-ones (8) with various substituted aldehydes were obtained by refluxing 1:1 molar equivalents of the reactants in dry ethanol for 6 h. The aminoquinazoline (8) was inturn obtained from 3,5-dibromoantharlinic acid via intermediate (7). All the synthesized compounds (9a-l) were evaluated for their anticonvulsant activity on albino mice by maximal electroshock method using phenytoin as a standard. The compound (9l) bearing a cinnamyl function displays a very high activity (82.74 %) at dose level of 100 mg/kg b.w. PMID:21188051

  4. Satellite remote sensing of H2SO4 aerosol using the 8- to 12-microns window region: Application to Mount Pinatubo

    NASA Technical Reports Server (NTRS)

    Ackerman, Steven A.; Strabala, Kathleen I.

    1994-01-01

    Monitoring stratospheric aerosols containing H2SO4 using the brightness temperature (BT) difference between 11 and 8.3 microns (BT(sub 8)-BT(sub 11)) spectral channels is demonstrated using theoretical calculations and satellite observations. Assuming an aqueous solution of 50% and 75% sulfuric acid, radiative transfer calculations indicate that over oceans an increase in the optical depth of the stratospheric aerosol results in an increase in BT(sub 8)-BT(sub 11). Theoretical simulations suggest that the technique is sensitive to visible optical depths greater than approximately 0.15. The simulations also demonstrate a lack of sensitivity to the particle size distribution. Changes in pre- and post-Pinatubo observations by the High-resolution Infrared Radiation Sounder 2 (HIRS2) on board the NOAA 10 are consistent with observed optical depth measurements and confirm the sensitivity of these channels to the presence of the aerosol. The technique is also applied to cold tropical convective clouds and desert regions where the signal, though evident, is less conclusive. Time series analysis is applied to the NOAA 10 and NOAA 12 combined BT(sub 8-BT(sub 11) observations to detect the periodicity of the spread of the volcanic aerosol. Over a region of the southern Pacific a 18- to 26-day period is present. Model simulations were conducted to demonstrate a trispectral with observations near 8, 11, and 12 microns. The trispectral approach has high potential in that the spectral signature of cirrus, water vapor, and H2SO4 aerosols are different. Observations from NOAA 10 and NOAA 11 are combined to demonstrate the capabilities of these infrared wavelengths of detecting the aerosol. The signal is clearly evident when a region of the South Atlantic is compared for pre- and post-Pinatubo conditions.

  5. Fluorocarbon assisted atomic layer etching of SiO2 and Si using cyclic Ar/C4F8 and Ar/CHF3 plasma

    DOE PAGESBeta

    Metzler, Dominik; Li, Chen; Engelmann, Sebastian; Bruce, Robert L.; Joseph, Eric A.; Oehrlein, Gottlieb S.

    2015-11-11

    The need for atomic layer etching (ALE) is steadily increasing as smaller critical dimensions and pitches are required in device patterning. A flux-control based cyclic Ar/C4F8 ALE based on steady-state Ar plasma in conjunction with periodic, precise C4F8 injection and synchronized plasma-based low energy Ar+ ion bombardment has been established for SiO2.1 In this work, the cyclic process is further characterized and extended to ALE of silicon under similar process conditions. The use of CHF3 as a precursor is examined and compared to C4F8. CHF3 is shown to enable selective SiO2/Si etching using a fluorocarbon (FC) film build up. Othermore » critical process parameters investigated are the FC film thickness deposited per cycle, the ion energy, and the etch step length. Etching behavior and mechanisms are studied using in situ real time ellipsometry and X-ray photoelectron spectroscopy. Silicon ALE shows less self-limitation than silicon oxide due to higher physical sputtering rates for the maximum ion energies used in this work, ranged from 20 to 30 eV. The surface chemistry is found to contain fluorinated silicon oxide during the etching of silicon. As a result, plasma parameters during ALE are studied using a Langmuir probe and establish the impact of precursor addition on plasma properties.« less

  6. Synthesis, thermal and electrical properties of Al-doped Bi4V1.8Cu0.2O10.7

    NASA Astrophysics Data System (ADS)

    Essalim, R.; Ammar, A.; Tanouti, B.; Mauvy, F.

    2016-08-01

    Partial substitution of copper with aluminum in Bi4V1.8Cu0.2O10.7 has led to the Bi4V1.8Cu0.2-xAlxO10.7+x/2 solid solution. X-ray diffraction and thermal analysis have shown that the compounds with x=0.05 and x=0.10 are tetragonal with γ‧ form of Bi4V2O11, while the compound with x=0.15 is of β polymorph. The effect of Al3+ doping on electrical conductivity has been studied using Electrochemical Impedance Spectroscopy. The electrical conductivity of doped samples along with the amount of Al3+ has been studied by electrochemical impedance spectroscopy in the temperature range 250-700 °C. The slope changes observed in the Arrhenius plots agree with the microstructural transitions occurring in these compounds. The highest ionic conductivity values are obtained for the sample with x=0.05.

  7. Electrical and magnetic properties of the spinel-type Li(Ti 0.8Cr 0.2) 2O 4

    NASA Astrophysics Data System (ADS)

    Kanno, Toshio; Awaka, Junji; Kariya, Fumihiro; Ebisu, Shuji; Nagata, Shoichi

    2006-05-01

    The spinel-type LiTi 2O 4 exhibits a superconducting transition at 13.7 K. The influence of substitution of Cr 3+ ion for Ti at spinel octahedral sites has been remarkably illustrated by previous researchers. The superconductivity is completely destroyed at 2.5% Cr 3+ ion by magnetic impurity effect. This short paper will present briefly electrical and magnetic properties of Li(Ti 0.80Cr 0.20) 2O 4 at rather high Cr 3+ ion substitution.

  8. Preparation of Y/sub 2/Ba/sub 4/Cu/sub 8/O/sub 20-//sub x/ thin films by thermal coevaporation

    SciTech Connect

    Berkley, D.D.; Kim, D.H.; Johnson, B.R.; Goldman, A.M.; Mecartney, M.L.; Beauchamp, K.; Maps, J.

    1988-08-22

    We report on the preparation of Y/sub 2/Ba/sub 4/Cu/sub 8/O/sub 20-//sub x/ (''248'') thin films by coevaporation using a combination of electron beam and Knudsen cell vapor sources. Our best film shows a superconducting onset at 80 K and zero resistance at 72 K. The x-ray diffraction patterns show nearly single phase ''248'' with a small YBa/sub 2/Cu/sub 3/O/sub 7-//sub x/ (''123'') impurity. It has been our experience that films can be annealed at least twice without displaying any shift in diffraction peak position.

  9. [Degradation of orange IV dye solution catalyzed by Fe (NO3)3-(NH4)2S2O8 modified GAC in the presence of H2O2].

    PubMed

    Zhang, Ying-Jie; Xu, Shu-Fen; Liao, Xia; Cao, Tian-Jing; Yang, Rong; Li, Da-Peng

    2012-10-01

    This study was designed to investigate the catalytic oxidation performance of modified GAC by Fe(NO3), and (NH4)2S2O8 in the process of H2O2. The effect of the initial concentration of H2O2, initial dye concentration, catalyst dosage, initial pH and temperature on the reaction was discussed. The results show that the catalyst of Fe/S/GAC has a better catalytic reactivity to decompose Orange IV compared with that of Fe/GAC. The catalyst could decompose H2O2 to degrade Orange IV effectively at pH 2.4-9.1. The removal rate of Orange IV increased with the increase of catalyst dosage. With the decrease of dye concentration, the reaction rate became faster, this reaction followed the second-order reaction kinetics with activation energy (Ea) of 68.19 kJ x mol(-1). Reuse of catalyst did not decrease the removal rate. Orange IV degradation mainly followed OH mechanism. PMID:23233975

  10. Anti-GD2 antibody 3F8 and barley-derived (1 → 3),(1 → 4)-β-D-glucan

    PubMed Central

    Modak, Shakeel; Kushner, Brian H.; Kramer, Kim; Vickers, Andrew; Cheung, Irene Y.; Cheung, Nai-Kong V.

    2013-01-01

    β-glucans are complex, naturally-occurring polysaccharides that prime leukocyte dectin and complement receptor 3. Based on our preclinical findings, indicating that oral barley-derived (1 → 3),(1 → 4)-β-D-glucan (BG) synergizes with the murine anti-GD2 antibody 3F8 against neuroblastoma, we conducted a Phase I clinical study to evaluate the safety of this combinatorial regimen in patients affected by chemoresistant neuroblastoma. In this setting, four cohorts of six heavily pre-treated patients bearing recurrent or refractory advanced-stage neuroblastoma were treated with 3F8 plus BG. Each cycle consisted of intravenous 3F8 at a fixed dose of 10 mg/m2/day plus concurrent oral BG, dose-escalated from 10 to 80 mg/Kg/day, for 10 d. Patients who did not develop human anti-mouse antibodies could be treated for up to 4 cycles. Twenty-four patients completed 50 cycles of therapy. All patients completed at least one cycle and were evaluable for the assessment of toxicity and responses. The maximum tolerated dose of BG was not reached, but two patients developed dose-limiting toxicities. These individuals developed grade 4 thrombocytopenia after one cycle of BG at doses of 20 mg/Kg/day and 40 mg/Kg/day, respectively. Platelet counts recovered following the administration of idiopathic thrombocytopenic purpura therapy. There were no other toxicities of grade > 2. Eleven and 13 patients manifested stable and progressive disease, respectively. Thirteen out of 22 patients with pre-treatment positive 123I-MIBG scans demonstrated clinical improvement on semiquantitative scoring. Responses did not correlate with BG dose or with in vitro cytotoxicity. In summary, 3F8 plus BG is well tolerated and shows antineoplastic activity in recurrent or refractory advanced-stage neuroblastoma patients. Further clinical investigation of this novel combinatorial immunotherapeutic regimen is warranted. PMID:23802080

  11. Fluorocarbon assisted atomic layer etching of SiO{sub 2} using cyclic Ar/C{sub 4}F{sub 8} plasma

    SciTech Connect

    Metzler, Dominik; Oehrlein, Gottlieb S.; Bruce, Robert L.; Engelmann, Sebastian; Joseph, Eric A.

    2014-03-15

    The authors demonstrate atomic layer etching of SiO{sub 2} using a steady-state Ar plasma, periodic injection of a defined number of C{sub 4}F{sub 8} molecules, and synchronized plasma-based Ar{sup +} ion bombardment. C{sub 4}F{sub 8} injection enables control of the deposited fluorocarbon (FC) layer thickness in the one to several Ångstrom range and chemical modification of the SiO{sub 2} surface. For low energy Ar{sup +} ion bombardment conditions, the physical sputter rate of SiO{sub 2} vanishes, whereas SiO{sub 2} can be etched when FC reactants are present at the surface. The authors have measured for the first time the temporal variation of the chemically enhanced etch rate of SiO{sub 2} for Ar{sup +} ion energies below 30 eV as a function of fluorocarbon surface coverage. This approach enables controlled removal of Ångstrom-thick SiO{sub 2} layers. Our results demonstrate that development of atomic layer etching processes even for complex materials is feasible.

  12. 8 CFR 292.4 - Appearances.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... this chapter he or she is authorized and qualified to appear as a representative as provided in 8 CFR 103.2(a)(3) and 292.1. Further proof of authority to act in a representative capacity may be...

  13. Pseudo Jahn-Teller distortion for a tricyclic carbon sulfide (C6S8) and its suppression in S-oxygenated dithiine (C4H4(SO2)2)

    NASA Astrophysics Data System (ADS)

    Pratik, Saied Md.; Chowdhury, Chandra; Bhattacharjee, Rameswar; Jahiruddin, Sk.; Datta, Ayan

    2015-10-01

    The tricyclic carbon-sulfide, C6S8 molecule containing two S-atoms in the 1,4-position of the central six-membered ring and one disulfide (Ssbnd S) and one thione (Cdbnd S) bond on the five membered rings on its either side (1) possesses a "butterfly flapping" type distorted ground state in the gas-phase and also in β-phase of the crystal. For the isolated molecule, better consideration of the S…S non-bonding interactions in the dithiine ring in the bent form at the M06-2X/6-31+G(d,p) level leads to a significant barrier for inversion of 2.4 kcal/mol which is 2-3 times more than that previously obtained by Weber and Dolg at the B3LYP/cc-pVTZ level due to underestimation of dispersion interactions at the B3LYP level. The origin of the distortion leading to lowering of symmetry for 1 (C2h → C2) is traced to vibronic mixing between the ground state (Ag) and the low lying excited states of Au symmetry through the au normal mode, a (1Ag + 1Au + 2Au + 3Au) × au pseudo Jahn-Teller effect (PJTE) problem. Based on fitting of the ground state APES to the lowest root of the 4 × 4 secular determinant, we calculate the linear vibronic coupling constants (F0i) between the relevant states. Similar in class to 1, the S-oxygenated derivative of dithiine, C4H4(SO2)2 (2) unlike most other dithiines, remains planar. The absence of the butterfly-type puckered structure in 2 is traced to the enhanced gap (Δ0) and very small vibronic coupling (F01) between the ground and PJT active state along the au distortion which suppress the PJT instability. Considering the separation of the occupied molecular orbital (OMO) and unoccupied molecular orbitals (UMO) energy levels provide a qualitative understanding for the contrasting behavior of 1 and 2. In effect, the PJT effect is shown to be a fruitful and general tool to describe the presence or lack of molecular distortion.

  14. Synthesis and characterization of a NaSICON series with general formula Na{sub 2.8}Zr{sub 2-y}Si{sub 1.8-4y}P{sub 1.2+4y}O{sub 12} (0=

    SciTech Connect

    Essoumhi, A.; Favotto, C.; Mansori, M.; Satre, P. . E-mail: satre@univ-tln.fr

    2004-12-01

    In this work, we present the synthesis and the characterization of ionic conducting ceramics of NaSICON-type (Natrium super ionic conductor). The properties of this ceramic make it suitable for use in electrochemical devices. These solid electrolytes can be used as sensors for application in the manufacturing of potentiometric gas sensors, for the detection of pollutant emissions and for environment control. The family of NaSICON that we studied has as a general formula Na{sub 2.8}Zr{sub 2-y}Si{sub 1.8-4y}P{sub 1.2+4y}O{sub 12} with 0=2.8}Zr{sub 1.775}Si{sub 0.9}P{sub 2.1}O{sub 12} composition.

  15. Conformational Interconversion of the trans-4-Hydroxynonenal-Derived (6S,8R,11S) 1,N2-Deoxyguanosine Adduct When Mismatched with Deoxyadenosine in DNA

    PubMed Central

    Huang, Hai; Wang, Hao; Lloyd, R. Stephen; Rizzo, Carmelo J.; Stone, Michael P.

    2009-01-01

    The (6S,8R,11S) 1,N2-HNE-dG adduct of trans-4-hydroxynonenal (HNE) was incorporated into the duplex 5′-d(GCTAGCXAGTCC)-3′•5′-d(GGACTAGCTAGC)-3′ [X=(6S,8R,11S) HNE-dG], in which the lesion was mismatched opposite dA. The (6S,8R,11S) adduct maintained the ring-closed 1,N2-HNE-dG structure. This was in contrast to when this adduct was correctly paired with dC, conditions under which it underwent ring opening and re-arrangement to diastereomeric minor groove hemiacetals [Huang, H., Wang, H., Qi, N., Lloyd, R.S., Harris, T.M., Rizzo, C.J., & Stone, M.P. (2008) J. Am. Chem. Soc. 130, 10898–10906]. The (6S,8R,11S) adduct exhibited a syn/anti conformational equilibrium about the glycosyl bond. The syn conformation was predominant in acidic solution. Structural analysis of the syn conformation revealed that X7 formed a distorted base pair with the complementary protonated A18. The HNE moiety was located in the major groove. Structural perturbations were observed at the neighbor C6•G19 and A8•T17 base pairs. At basic pH, the anti conformation of X7 was the major species. At X7 the 1,N2-HNE-dG intercalated and displaced the complementary A18 in the 5′-direction, resulting in a bulge at the X7•A18 base pair. The HNE aliphatic chain was oriented towards the minor groove. The Watson-Crick hydrogen bonding of the neighboring A8•T17 base pair was also disrupted. PMID:19053179

  16. Gas-phase reactions of the bare Th2+ and U2+ ions with small alkanes, CH4, C2H6, and C3H8: experimental and theoretical study of elementary organoactinide chemistry.

    PubMed

    Di Santo, Emanuela; Santos, Marta; Michelini, Maria C; Marçalo, Joaquim; Russo, Nino; Gibson, John K

    2011-02-16

    The gas-phase reactions of two dipositive actinide ions, Th(2+) and U(2+), with CH(4), C(2)H(6), and C(3)H(8) were studied by both experiment and theory. Fourier transform ion cyclotron resonance mass spectrometry was employed to study the bimolecular ion-molecule reactions; the potential energy profiles (PEPs) for the reactions, both observed and nonobserved, were computed by density functional theory (DFT). The experiments revealed that Th(2+) reacts with all three alkanes, including CH(4) to produce ThCH(2)(2+), whereas U(2+) reacts with C(2)H(6) and C(3)H(8), with different product distributions than for Th(2+). The comparative reactivities of Th(2+) and U(2+) toward CH(4) are well explained by the computed PEPs. The PEPs for the reactions with C(2)H(6) effectively rationalize the observed reaction products, ThC(2)H(2)(2+) and UC(2)H(4)(2+). For C(3)H(8) several reaction products were experimentally observed; these and additional potential reaction pathways were computed. The DFT results for the reactions with C(3)H(8) are consistent with the observed reactions and the different products observed for Th(2+) and U(2+); however, several exothermic products which emerge from energetically favorable PEPs were not experimentally observed. The comparison between experiment and theory reveals that DFT can effectively exclude unfavorable reaction pathways, due to energetic barriers and/or endothermic products, and can predict energetic differences in similar reaction pathways for different ions. However, and not surprisingly, a simple evaluation of the PEP features is insufficient to reliably exclude energetically favorable pathways. The computed PEPs, which all proceed by insertion, were used to evaluate the relationship between the energetics of the bare Th(2+) and U(2+) ions and the energies for C-H and C-C activation. It was found that the computed energetics for insertion are entirely consistent with the empirical model which relates insertion efficiency to the

  17. Burovaite-Ca, (Na,K)4Ca2(Ti,Nb)8[Si4O12]4(OH,O)8·12H2O, a new labuntsovite-group mineral species and its place in low-temperature mineral formation in pegmatites of the Khibiny pluton, Kola Peninsula, Russia

    NASA Astrophysics Data System (ADS)

    Azarova, Yu. V.; Shlyukova, Z. V.; Zolotarev, A. A.; Organova, N. I.

    2009-12-01

    This paper presents data on burovaite-Ca, the first Ti-dominant member of the labuntsovite group with a calcium D-octahedron. The idealized formula of burovaite-Ca is (K,Na)4Ca2(Ti,Nb)8[Si4O12]4(OH,O)8 · 12H2O. The mineral has been found in the hydrothermal zone of aegirine-microcline pegmatite located in khibinite at Mt. Khibinpakhkchorr, the Khibiny pluton, Kola Peninsula, Russia. Radiaxial intergrowths of burovaite-Ca and labuntsovite-Mn associated with lemmleynite-Ba, analcime, and apophyllite have been identified in caverns within microcline. The mean composition of the mineral is as follows, wt %: 3.72 Na2O, 2.76 K2O, 4.22 CaO, 0.47 SrO, 0.23 BaO, 0.01 MnO, 0.30 Fe2O3, 0.14 Al2O3, 42.02 SiO2, 17.30 TiO2, 15.21 Nb2O5, 12.60 H2O (measured); the total is 98.98. Its empirical formula has been calculated on the basis of [(Si,Al)16O48]: {(Na3.10K1.07Ca0.37Sr0.04Ba0.04)4.62}(Ca1.28Zn0.01)1.29(Ti4.97Nb2.56Fe0.08Ta0.02)7.63(Si15.93Al0.07)16O48(OH6.70O0.93)7.63 · 12H2O. The strongest lines in the X-ray powder diffraction pattern of burovaite-Ca ( I-d Å] are as follows: 70-7.08, 40-6.39, 40-4.97, 30-3.92, 40-3.57, 100-3.25, 70-3.11, 50-2.61, 70-2.49, 40-2.15, 50-2.05, 70-1.712, 70-1.577, and 70-1.444. The structure of burovaite-Ca was solved by A.A. Zolotarev, Jr. The mineral is monoclinic, space group C2/ m. The unit-cell dimensions are a = 14.529(3), b = 14.203(3), c = 7.899(1), β = 117.37(1)°, V = 1447.57 Å3. Burovaite-Ca is an isostructural Ti-dominant analogue of karupmøllerite-Ca and gjerdingenite-Ca. Two stages of mineral formation—pegmatite proper and hydrothermal—have been recognized in the host pegmatite. The hydrothermal stage included K-Ba-Na, Na-K-Ca, and Na-Sr substages. Burovaite-Ca is related to the intermediate Na-K-Ca substage. At the first substage, labuntsovite-Mn and lemmleynite-Ba were formed, and tsepinite-Na, paratsepinite-Nd, and tsepinite-Sr were formed at the final substage. Thus, the sequence of crystallization of labuntsovite

  18. Luminescence properties of Ca{sub 14}Mg{sub 2}(SiO{sub 4}){sub 8}:Eu{sup 2+} from various Eu{sup 2+} sites for white-light-emitting diodes

    SciTech Connect

    Zhang, Jia Jiang, Cheng

    2014-12-15

    Ca{sub 14}Mg{sub 2}(SiO{sub 4}){sub 8}:Eu{sup 2+} phosphors were synthesized by solid-state reaction method, and their luminescence properties were investigated. In the emission spectra, several overlapping emission bands originating from various Eu{sup 2+} sites were found. Eu{sup 2+} in Ca{sub 14}Mg{sub 2}(SiO{sub 4}){sub 8} exhibits green emission around 506 nm, and the sample doped with 0.1 mol% Eu{sup 2+} shows the strongest brightness under 365 nm excitation with the quantum efficiency of 63.6%. In the excitation spectra, strong and broad excitation bands from 250 to 450 nm were observed, which could well match with the emission wavelength of the light-emitting diode chip. The fabrication test on the InGaN chip indicates the Ca{sub 14}Mg{sub 2}(SiO{sub 4}){sub 8}:Eu{sup 2+} phosphor could be promising candidate for white light-emitting diodes.

  19. La 2NiO 4+ δ potential cathode material on La 0.9Sr 0.1Ga 0.8Mg 0.2O 2.85 electrolyte for intermediate temperature solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Escudero, María José; Fuerte, Araceli; Daza, Loreto

    La 2NiO 4+ δ, a mixed ionic-electronic conducting oxide with K 2NiF 4 type structure, has been studied as cathode material with La 0.9Sr 0.1Ga 0.8Mg 0.2O 2.85 (LSGM) electrolyte for intermediate solid oxide fuel cells (IT-SOFCs). XRD results reveal excellent chemical compatibility between the La 2NiO 4+ δ sample and LSGM electrolyte. A single cell (0.22 cm 2 active area) was fabricated with La 2NiO 4+ δ as cathode, Ni-Sm 0.2Ce 0.8O 1.9 (2:1; w/w) as anode and LSGM as electrolyte. A thin buffer layer of Sm 0.2Ce 0.8O 1.9 (SDC) between anode and electrolyte was used to avoid possible interfacial reactions. The cell was tested under humidified H 2 and stationary air as fuel and oxidant, respectively. The electrochemical behaviour was evaluated by means of current-voltage curves and impedance spectroscopy. Microstructure and morphology of the cell components were analysed by SEM-EDX after testing. The maximum power densities were 160, 226, and 322 mW cm -2 at 750, 800 and 850 °C, respectively with total polarisation resistances of 0.77, 0.48 and 0.31 Ω cm 2 at these temperatures. Cell performance remained stable when a current density of 448 mA cm -2 was demanded for 144 h at 800 °C, causing no apparent degradation in the cell. The performance of this material may be further improved by reducing the electrolyte thickness and optimisation of the electrode microstructure.

  20. Pressure-induced isomerization of a heterometallic rhodium-gold cluster compound: (Rh sub 2 (. mu. -Cl) sub 2 (CNC sub 8 H sub 9 ) sub 4 (. mu. -AuPPh sub 3 )) sub 2 (PF sub 6 ) sub 2

    SciTech Connect

    Bray, K.L.; Drickamer, H.G.; Shapley, J.R. ); Mingos, D.M.P.; Watson, M.J. )

    1991-02-20

    Mingos et al. have prepared two isomers of the cluster compound (Rh{sub 2}(mu-Cl{sub 2})(CNC{sub 8}H{sub 9}){sub 4}(mu-AuPPh{sub 3})){sub 2}(PF{sub 6}){sub 2} and have characterized these isomers using single crystal x-ray techniques. The volumes per cluster cation were found to be very similar for both isomers, 1,430 and 1,413 angstroms, and the Rh-Rh bond lengths were found to be 3.262 and 3.008 angstroms for the same isomer. The cluster skeletal geometries were found to differ only at an interior link, and applied pressure appeared to induce a conformational transition around this bond.

  1. Tunable photoluminescence properties of Ca{sub 8}NaLa(PO{sub 4}){sub 6}F{sub 2}:Eu{sup 2+},Mn{sup 2+} phosphor under UV excitation

    SciTech Connect

    Zhang, Fen; Lan, Tong; Tang, Wanjun

    2015-04-15

    Highlights: • Ca{sub 8}NaLa(PO{sub 4}){sub 6}F{sub 2}:Eu{sup 2+},Mn{sup 2+} was prepared by a combustion-assisted synthesis method. • The phosphor presents blue and yellow double color emissions. • Efficient energy transfer from Eu{sup 2+} to Mn{sup 2+} in this phosphor is observed obviously. • White emitting was realized in Ca{sub 8}NaGd(PO{sub 4}){sub 6}F{sub 2}:0.10Eu{sup 2+},0.32Mn{sup 2+},0.10B phosphor. - Abstract: A series of Eu{sup 2+} and Mn{sup 2+} coactivated Ca{sub 8}NaLa(PO{sub 4}){sub 6}F{sub 2} (CNLF) phosphors have been synthesized by a combustion-assisted synthesis method. The investigation revealed that Ca{sub 8}NaLa(PO{sub 4}){sub 6}F{sub 2} crystallized in a hexagonal crystal system with the space group P6{sub 3}/m (176). The Eu{sup 2+} activated phosphors can be efficiently excited in the range of 270–400 nm and give intense blue emission peaking at 451 nm. By codoping the Eu{sup 2+} and Mn{sup 2+} ions into the CNLF host and singly varying the doping content of the Mn{sup 2+} ion, tunable colors from blue to white and eventually to yellow are obtained in CNLF:Eu{sup 2+},Mn{sup 2+} phosphors under the irradiation of 330 nm. The energy transfer from Eu{sup 2+} to Mn{sup 2+} in CNLF:Eu{sup 2+},Mn{sup 2+} has been demonstrated to be a resonant type via a dipole–dipole mechanism and the critical distance of energy transfer from Eu{sup 2+} to Mn{sup 2+} was estimated to be about 11.9 Å. The investigation indicates that the obtained samples might have potential application in white LEDs.

  2. Cysteinyl peptides of rabbit muscle pyruvate kinase labeled by the affinity label 8-((4-bromo-2,3-dioxobutyl)thio)adenosine 5 prime -triphosphate

    SciTech Connect

    Vollmer, S.H.; Colman, R.F. )

    1990-03-13

    The affinity label 8-((4-bromo-2,3-dioxobutyl)thio)adenosine 5{prime}-triphosphate (8-BDB-TA-5{prime}-TP) reacts covalently with rabbit muscle pyruvate kinase, incorporating 2 mol of reagent/mol of enzyme subunit upon complete inactivation. Protection against inactivation is provided by phosphoenolpyruvate, K{sup +}, and Mn{sup 2+} and only 1 mol of reagent/mol of subunit is incorporated. The authors have now identified the resultant modified residues. After reaction with 8-BDB-TA-5{prime}-TP at pH 7.0, modified enzyme was incubated with ({sup 3}H)NaBH{sub 4} to reduce the carbonyl groups of enzyme-bound 8-BDB-TA-5{prime}-TP and to introduce a radioactive tracer into the modified residues. Following carboxymethylation and digestion with trypsin, the radioactive peptides were separated on a phenylboronate agarose column followed by reverse-phase high-performance liquid chromatography in 0.1% trifluoroacetic acid with an acetonitrile gradient. Gas-phase sequencing gave the cysteine-modified peptides Asn{sup 162}-Ile-Cys-Lys{sup 165} and Cys{sup 151}-Asp-Glu-Asn-Ile-Leu-Trp-Leu-Asp-Tyr-Lys{sup 161}, with a smaller amount of Asn{sup 43}-Thr-Gly-Ile-Ile-Cys-Thr-Ile-Gly-Pro-Ala-Ser-Arg{sup 55}. Reaction in the presence of the protectants phosphoenolpyruvate, K{sup +}, and Mn{sup 2+} yielded Asn-Ile-Cys-Lys as the only labeled peptide, indicating that inactivation is caused by modification of Cys{sup 151} and Cys{sup 48}.

  3. Synthesis and physical properties of (Pr 1-xRE x)Ba 2Cu 4O 8 oxides (RE dbnd Y, Yb, Nd, Gd)

    NASA Astrophysics Data System (ADS)

    Horii, Shigeru; Yamada, Y.; Yamada, N.; Hirabayashi, I.; Mizutani, U.

    1997-08-01

    PrBa 2Cu 4O 8(Pr124) does not exhibit superconductivity, but its resistivity shows a metallic behavior below 180K. This behavior is in a sharp contrast to the semiconducting one of PrBa 2Cu 3O 7-y(Pr123). A substitution of Pr by RE(Rare earth elements) in the Pr123 is known to induce the superconductivity. For example, the critical RE concentration, XTC, corresponding to the onset of superconductivity for RE dbnd Y, Yb, Gd and Nd has been reported to be 0.45, 0.35, 0.5 and 0.65, respectively. In thi study, we could prepare stoichiometric (Pr 1-xRE x)Ba2Cu 4O 8 oxides by using high oxygen pressure technique, and investigated the physical properties. In the case of RE dbnd Y, Yb and Gd, the semiconducting region has disappeared and the superconductivity appeared at x=0.3, 0.25 and 0.4, respectively. This result means that Pr-effect in the 124 system is smaller than that in the 123 system.

  4. Enhanced optophysical properties of poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3] thiadiazol-4,8-diyl)] via addition of TiO{sub 2} nanoparticles

    SciTech Connect

    Fuzi, Siti Aishah Ahmad Jumali, Mohammad Hafizuddin Hj Al-Asbahi, Bandar Ali Abdulqader

    2015-09-25

    This work investigated the effect on 5 wt% addition of TiO{sub 2} nanoparticles (NPs) on the optical absorption characteristics of Poly[(9,9-di-n-octylfluorenyl-2,7-diyl)-alt-(benzo[2,1,3] thiadiazol-4,8-diyl)] (F8BT). Both materials were mixed using solution blending method and then spin coated onto ITO-coated glass substrate at 1000 rpm for 30s. The optical properties of the nanocomposite were determined using UV-Vis spectroscopy. Compares to pristine film, the absorption peak of the nanocomposite film improved and shifted to longer wavelength indicating reduction in the direct and indirect band gaps. Better optophysical properties of F8BT/TiO{sub 2} nanocomposites is believed due to compatible band structures and efficient charge trapping effect displayed by the NPs.

  5. 6-Meth­oxy-2-phenyl-4,4a,6,7,8,8a-hexa­hydro-2H-pyrano[3,2-d][1,3]dioxine-7,8-diyl bis­(4-methyl­benzene-1-sulfonate)

    PubMed Central

    Wardell, James L.; Tiekink, Edward R. T.

    2012-01-01

    In the title α-D-glucopyran­oside derivative, C28H30O10S2, each heterocyclic ring adopts a chair conformation. In the tri­substituted ring, the meth­oxy and one sulfonate group occupy axial positions, whereas the second sulfonate group occupies an axial position. The phenyl group on the other ring is in an equatorial position. In the crystal, supra­molecular chains propagating along [100] are formed through C—H⋯O and C—H⋯π inter­actions. PMID:22412635

  6. L-nucleotides and 8-methylguanine of d(C1m8G2C3G4C5LG6LC7G8C9G10)2 act cooperatively to promote a left-handed helix under physiological salt conditions

    PubMed Central

    Cherrak, Ilham; Mauffret, Olivier; Santamaria, Fanny; Hocquet, Alexandre; Ghomi, Mahmoud; Rayner, Bernard; Fermandjian, Serge

    2003-01-01

    The structure and thermal stability of a hetero chiral decaoligodeoxyribonucleotide duplex d(C1m8 G2C3G4C5LG6LC7G8C9G10)d(C11m8G12C13G14C15LG16LC17G18C19G20) (O1) with two contiguous pairs of enantiomeric 2′-deoxy-l-ribonucleotides (C5LG6L/C15LG16L) at its centre and an 8-methylguanine at position 2/12 was analysed by circular dichroism, NMR and molecular modelling. O1 resolves in a left-handed helical structure already at low salt concentration (0.1 M NaCl). The central l2-sugar portion assumes a B* left-handed conformation (mirror-image of right-handed B-DNA) while its flanking d4-sugar portions adopt the known Z left-handed conformation. The resulting Z4–B2*–Z4 structure (left-handed helix) is the reverse of that of B4–Z2*–B4 (right-handed helix) displayed by the nearly related decaoligodeoxyribonucleotide d(mC1G2mC3G4C5L G6LmC7G8mC9G10)2, at the same low salt concentration (0.1 M NaCl). In the same experimental conditions, d(C1m8G2C3G4C5G6C7G8C9G10)2 (O2), the stereoregular version of O1, resolves into a right-handed B-DNA helix. Thus, both the 8-methylguanine and the enantiomeric step CLpGL at the centre of the molecule are needed to induce left-handed helicity. Remarkably, in the various heterochiral decaoligodeoxyribonucleotides so far analysed by us, when the central CLpGL adopts the B* (respectively Z*) conformation, then the adjacent steps automatically resolves in the Z (respectively B) conformation. This allows a good optimisation of the base–base stackings and base–sugar van der Waals interactions at the ZB*/B*Z (respectively BZ*/Z*B) junctions so that the Z4–B2*–Z4 (respectively B4–Z2*–B4) helix displays a Tm (∼65°C) that is only 5°C lower than the one of its homochiral counterpart. Here we anticipate that a large variety of DNA helices can be generated at low salt concentration by manipulating internal factors such as sugar configuration, duplex length, nucleotide composition and base methylation. These helices can

  7. Crystal structure, spectroscopic, magnetic and electronic structure studies of a novel Cu(II) amino acid complex [Cu(L-arg)2(H2O)]2(P4O12)·8H2O

    NASA Astrophysics Data System (ADS)

    Hemissi, H.; Nasri, M.; Abid, S.; Al-Deyab, S. S.; Dhahri, E.; Hlil, E. K.; Rzaigui, M.

    2012-12-01

    Single crystals of a novel copper (II) complex with the amino acid L-arginine (L-arg) and cyclotetraphosphate, [Cu(L-arg)2(H2O)]2(P4O12)·8H2O, were prepared in aqueous solution and were characterized by X-ray diffraction, spectroscopy (diffuse reflectance, UV-vis and IR) and thermal analysis. Magnetic measurements and electronic structure calculations were also performed. Crystal structure determination reveals that this compound has a nonsymmetrical atomic arrangement, containing mainly a binuclear [Cu(L-arg)2(H2O)]24+ cation and an uncoordinated cyclotetraphosphate counter-anion (P4O124-). The tetravalent cation contains two independent Cu(II) ions in two different chemical environments. This compound exhibits an antiferromagnetic (AFM) to paramagnetic (PM) phase transition at a temperature (TN) lower than 2 K. The values of paramagnetic Curie-Weiss temperature (θcw) and the exchange parameter (J/KB) emphasize the existence of an antiferromagnetic interaction between the neighboring copper ions.

  8. An octanuclear molybdenum(VI) complex containing coordinatively bound 4,4'-di-tert-butyl-2,2'-bipyridine, [Mo8O22(OH)4(di-tBu-bipy)4]: synthesis, structure, and catalytic epoxidation of bio-derived olefins.

    PubMed

    Amarante, Tatiana R; Neves, Patrícia; Tomé, Cátia; Abrantes, Marta; Valente, Anabela A; Paz, Filipe A Almeida; Pillinger, Martyn; Gonçalves, Isabel S

    2012-03-19

    The reaction of [MoO(2)Cl(2)(di-tBu-bipy)] (1) (di-tBu-bipy = 4,4'-di-tert-butyl-2,2'-bipyridine) with water at 100-120 °C in a Teflon-lined stainless steel autoclave, in an open reflux system, or in a microwave synthesis system gave the octanuclear complex [Mo(8)O(22)(OH)(4)(di-tBu-bipy)(4)] (2) as a microcrystalline powder in good yields. Single crystals of 2 suitable for X-ray diffraction were obtained by the reaction of MoO(3) and di-tBu-bipy in water at 160 °C for 3 days. The molecular structure of 2 comprises a purely inorganic core, Mo(4)O(8)(μ(3)-OH)(2)(μ(2)-O)(2), attached to two peripheral oxo-bridged binuclear units, Mo(2)O(4)(μ(2)-O)(2)(OH)(di-tBu-bipy)(2). The inorganic core is composed of a unique assembly of four {MoO(5)} distorted square pyramids connected to each other via edge-sharing. Overall, the octanuclear complex adopts a highly distorted form strongly resembling an "S"-shaped molecular unit. Complex 2 was applied in the catalytic epoxidation of the biorenewable olefins DL-limonene (Lim) and methyl oleate (Ole), using tert-butylhydroperoxide (TBHP) as an oxygen donor, under mild reaction conditions (55 °C, air). The reactions of Lim and Ole gave the respective epoxide monomers in fairly high selectivities at high conversions (89% 1,2-epoxy-p-menth-8-ene selectivity at 96% Lim conversion; 99% methyl 9,10-epoxystearate selectivity at 94% Ole conversion, reached within 24 h reaction). Iodometric titrations revealed no measurable "non-productive" decomposition of TBHP. PMID:22372402

  9. Evidence for a High-Pressure Phase Transition of ε-2,4,6,8,10,12-hexanitrohexaazaisowurtzitane (CL-20) Using Vibrational Spectroscopy

    SciTech Connect

    Ciezak, J.; Jenkins, T; Liu, Z

    2007-01-01

    The high-pressure response of {epsilon}-2,4,6,8,10,12-hexanitrohexaazaisowurtizane (CL-20) has been examined to 27 GPa in diamond anvil cells using vibrational spectroscopy. The results reveal evidence of an {epsilon}{yields}{Upsilon} pressure-induced phase transition between 4.1 and 6.4 GPa and suggest the existence of a {Upsilon}{yields}{zeta} transition near 18.7 GPa. Several Raman and infrared frequencies were found to decrease in intensity as the phase boundaries are approached. An anomalous intensity increase was noted in the C-N-C infrared mode that is believed to result from an increase in the Raman cross-section due to a stronger interlayer coupling under pressure.

  10. New single-molecule magnet based on Mn12 oxocarboxylate clusters with mixed carboxylate ligands, [Mn12O12(CN-o-C6H4CO2)12(CH3CO2)4(H2O)48CH2Cl2: Synthesis, crystal and electronic structure, magnetic properties.

    PubMed

    Kushch, L A; Sasnovskaya, V D; Dmitriev, A I; Yagubskii, E B; Koplak, O V; Zorina, L V; Boukhvalov, D W

    2012-11-28

    A new high symmetry Mn(12) oxocarboxylate cluster [Mn(12)O(12)(CN-o-C(6)H(4)CO(2))(12)(CH(3)CO(2))(4)(H(2)O)(4)]·8CH(2)Cl(2) (1) with mixed carboxylate ligands is reported. It was synthesized by the standard carboxylate substitution method. 1 crystallizes in the tetragonal space group I4(1)/a. Complex 1 contains a [Mn(12)O(12)] core with eight CN-o-C(6)H(4)CO(2) ligands in the axial positions, four CH(3)CO(2) and four CN-o-C(6)H(4)CO(2) in equatorial positions. Four H(2)O molecules are bonded to four Mn atoms in an alternating up, down, up, down arrangement indicating a 1 : 1 : 1 : 1 isomer. The Mn(12) molecules in 1 are self-assembled by complementary hydrogen C-H···N bonds formed with participation of the axial o-cyanobenzoate ligands of the adjacent Mn(12) clusters. The lattice solvent molecules (CH(2)Cl(2)) are weakly interacted with Mn(12) units that results in solvent loss immediately after removal of the crystals from the mother liquor. The electronic structure and the intramolecular exchange parameters have been calculated. Mn 3d bands of 1 are rather broad, and the center of gravity of the bands shifts down from the Fermi level. The overlap between Mn 3d bands and 2p ones of the oxygen atoms from the carboxylate bridges is higher than in the parent Mn(12)-acetate cluster. These changes in the electronic structure provide a significant difference in the exchange interactions in comparison to Mn(12)-acetate. The magnetic properties have been studied on a dried (solvent-free) polycrystalline sample of 1. The dc magnetic susceptibility measurements in the 2-300 K temperature range support a high-spin ground state (S = 10). A bifurcation of temperature dependencies of magnetization taken under zero field cooled and field cooled conditions observed below 4.5 K is due to slow magnetization relaxation. Magnetization versus applied dc field exhibited a stepwise hysteresis loop at 2 K. The ac magnetic susceptibility data revealed the frequency dependent out

  11. Synthesis, optical and photoelectrical characterizations of the novel 10-chloro-6H,8H-dichromeno[2,3-b:3‧,4‧-e]pyridine-6,8-dione (CDPD) and its photodiode application

    NASA Astrophysics Data System (ADS)

    Ibrahim, Magdy A.; Farag, A. A. M.; Roushdy, N.; El-Gohary, Nasser M.

    2016-01-01

    Friedländer condensation of 2-amino-6-chlorochromone-3-carboxaldehyde (1) with 4-hydroxycoumarin (2) under basic conditions afforded 10-chloro-6H,8H-dichromeno[2,3-b:3‧,4‧-e]pyridine-6,8-dione (3) (CDPD). Structure of CDPD was deduced based on its correct elemental analysis and spectral data (IR, 1H NMR, 13C NMR and mass spectra). Crystalline structure by using X-ray diffraction confirms a polycrystalline nature of the powder and films with monoclinic system. A flower-like morphology was resolved for the high magnification images of scanning electron microscopy. Three direct optical band gaps were obtained and found to be 1.17, 2.24 and 3.40 eV, respectively. A sharp single peak of photoluminescence in the visible region was observed and centered at around 683 nm as well as another two peaks at 417 and 386 nm. Rectification characteristics of the device based CDPD indicates that the device behaves as a diode. A maximum value of photosensitivity of the device was obtained under effect of 60 mW/cm2 and bias voltage of 1.25 V. The phototransient characteristics of the device confirm that the device can be operated as a photodiode.

  12. Synthesis and structural study of 4-(2-chlorophenyl)-2-ethoxy-5,6,7,8,9,10-hexahydrocycloocta[B]pyridine-3-carbonitrile

    NASA Astrophysics Data System (ADS)

    Fathima, K. Saiadali; Vasumathi, M.; Anitha, K.

    2016-05-01

    The novel organic material C20H21ClN2O was synthesized by One-Pot synthesis method and the single crystals were grown by slow evaporation solution growth technique. The crystal structure was elucidated by subjecting the grown crystals to the single crystal x-ray diffraction analysis and was refined by full matrix least-squares method to R=0.039 for 2746 reflections. Crystal system of the grown crystal was found to be monoclinic with the space group P21/a and a=9.196(4) Å, b=13.449(4) Å, c=14.818(4) Å, β= 101.542(3)°, V=1795.6(11) Å3 and Z=4. In this crystal structure, cyclooctanone prefers to reside in a chair-boat conformation. The structure is stabilized by attractive molecular force such as CH/π interaction called hydrophobic interaction.

  13. 8 CFR 208.4 - Filing the application.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... multilateral agreement, only as provided in 8 CFR 208.30(e). For provisions relating to the authority of immigration judges with respect to section 208(a)(2)(A), see 8 CFR 1240.11(g). (b) Filing location. Form I-589... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false Filing the application. 208.4 Section...

  14. Crystal structure of (4E)-4-(8-meth-oxy-2H-chromen-2-yl-idene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one.

    PubMed

    Salim, Muhammad; Munawar, Munawar Ali; Tahir, Muhammad Nawaz; Shahid, Muhammad; Malik, Khizar Iqbal

    2015-06-01

    In the title compound, C20H16N2O3, the phenyl substituent attached to the pyrazole ring makes a dihedral angle of 4.87 (7)° with the rest of the mol-ecule. In the crystal, mol-ecules are connected into inversion dimers of the R 2 (2)(14) type by pairs of C-H⋯O inter-actions. π-π inter-actions exist between the benzene and pyrazole rings at a distance of 3.701 (1) Å. Similarly, π-π inter-actions are present at a centroid-centroid distance of 3.601 (1) Å between the oxygen-containing heterocyclic ring and meth-oxy substituted aromatic ring of a neighbouring mol-ecule. Additional C-H⋯π and C=O⋯π inter-actions are also observed. PMID:26090198

  15. Transport and Cu NMR studies of charge and spin dynamics in PrBa{sub 2}Cu{sub 4}O{sub 8}

    SciTech Connect

    Kikuchi, Jun; Terasaki, Ichiro; Machi, Takato; Seiji, Nobuaki

    1996-11-01

    The charge and spin dynamics in PrBa{sub 2}Cu{sub 4}O{sub 8} are investigated by means of transport and Cu NMR measurements. The magnetoresistance was found to be very small at high temperatures and increase rapidly with decreasing temperature below {approximately}100 K, which may be ascribed to the dimensional crossover from one to two dimensions in the charge transport in the CuO double chains. While the NMR signal from the chain Cu sites persists down to 4.2 K without any appreciable line broadening, the signal from the planar Cu sites disappears below {approximately}250 K indicating the long-range antiferromagnetic order of plane Cu moments. This is consistent with the view of metallic conduction along the quasi one-dimensional CuO chains.

  16. Microwave-enhanced electrochemical cycling performance of the LiNi0.2Mn1.8O4 spinel cathode material at elevated temperature.

    PubMed

    Raju, Kumar; Nkosi, Funeka P; Viswanathan, Elumalai; Mathe, Mkhulu K; Damodaran, Krishnan; Ozoemena, Kenneth I

    2016-05-14

    The well-established poor electrochemical cycling performance of the LiMn2O4 (LMO) spinel cathode material for lithium-ion batteries at elevated temperature stems from the instability of the Mn(3+) concentration. In this work, a microwave-assisted solid-state reaction has been used to dope LMO with a very low amount of nickel (i.e., LiNi0.2Mn1.8O4, herein abbreviated as LMNO) for lithium-ion batteries from Mn3O4 which is prepared from electrolytic manganese oxide (EMD, γ-MnO2). To establish the impact of microwave irradiation on the electrochemical cycling performance at an elevated temperature (60 °C), the Mn(3+) concentration in the pristine and microwave-treated LMNO samples was independently confirmed by XRD, XPS, (6)LiMAS-NMR and electrochemical studies including electrochemical impedance spectroscopy (EIS). The microwave-treated sample (LMNOmic) allowed for the clear exposure of the {111} facets of the spinel, optimized the Mn(3+) content, promoting structural and cycle stability at elevated temperature. At room temperature, both the pristine (LMNO) and microwave-treated (LMNOmic) samples gave comparable cycling performance (>96% capacity retention and ca. 100% coulombic efficiency after 100 consecutive cycling). However, at an elevated temperature (60 °C), the LMNOmic gave an improved cycling stability (>80% capacity retention and ca. 90% coulombic efficiency after 100 consecutive cycling) compared to the LMNO. For the first time, the impact of microwave irradiation on tuning the average manganese redox state of the spinel material to enhance the cycling performance of the LiNi0.2Mn1.8O4 at elevated temperature and lithium-ion diffusion kinetics has been clearly demonstrated. PMID:27113855

  17. Volumetric Properties of the Mixture Propenenitrile C3H3N + C4H8O2 Ethyl ethanoate (VMSD1412, LB4274_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C4H8O2 Ethyl ethanoate (VMSD1412, LB4274_V)' providing data by calculation of isentropic compressibility from low-pressure density and thermodynamic speed of sound data at variable mole fraction and constant temperature, in the single-phase region(s).

  18. Volumetric Properties of the Mixture Propenenitrile C3H3N + C4H8O2 Ethyl ethanoate (VMSD1212, LB4262_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C4H8O2 Ethyl ethanoate (VMSD1212, LB4262_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  19. Volumetric Properties of the Mixture Propenenitrile C3H3N + C4H8O2 Ethyl ethanoate (VMSD1111, LB4252_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C4H8O2 Ethyl ethanoate (VMSD1111, LB4252_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  20. Volumetric Properties of the Mixture Propenenitrile C3H3N + C4H8O2 Ethyl ethanoate (VMSD1511, LB4268_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Propenenitrile C3H3N + C4H8O2 Ethyl ethanoate (VMSD1511, LB4268_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  1. Volumetric Properties of the Mixture 1,3-Dioxane C4H8O2 + C6H12 Cyclohexane (VMSD1511, LB5121_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture 1,3-Dioxane C4H8O2 + C6H12 Cyclohexane (VMSD1511, LB5121_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  2. Volumetric Properties of the Mixture 1,3-Dioxane C4H8O2 + C6H12 Cyclohexane (VMSD1111, LB5124_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture 1,3-Dioxane C4H8O2 + C6H12 Cyclohexane (VMSD1111, LB5124_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  3. Heat of Mixing and Solution of 1,3-Dioxane C4H8O2 + C6H12 Cyclohexane (HMSD1111, LB4308_H)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Heat of Mixing and Solution of 1,3-Dioxane C4H8O2 + C6H12 Cyclohexane (HMSD1111, LB4308_H)' providing data from direct low-pressure calorimetric measurement of molar excess enthalpy at variable mole fraction and constant temperature.

  4. Volumetric Properties of the Mixture 1,3-Dioxane C4H8O2 + C6H12 Cyclohexane (VMSD1212, LB5126_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume B 'Binary Liquid Systems of Nonelectrolytes II' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture 1,3-Dioxane C4H8O2 + C6H12 Cyclohexane (VMSD1212, LB5126_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  5. Synthesis and Electrochemical Studies of LiNi0.2Co0.8VO4 Cathode Material by Sol-Gel Method

    NASA Astrophysics Data System (ADS)

    Prakash, D.; Sanjeeviraja, C.

    2013-07-01

    Lithium nickel cobalt vanadate (LiNi0.2Co0.8VO4) cathode material was prepared by using sol-gel method. Rietveld refinement analysis of powder x-ray diffraction (PXRD) pattern confirmed the prepared compound having cubic structure and showed no evidence of secondary phase peaks. The field emission scanning microscopy (FESEM) image of the compound showed that the particles have submicron size. The x-ray photoelectron spectroscopy (XPS) results showed that the oxidation states of cobalt and vanadium was +3 and +5, respectively. The electrochemical performance of the cathode material was also performed.

  6. A Study on the Base–Catalyzed Reverse Vinylogous Aldol Reaction of (4aβ,5β)-4,4a,5,6,7,8-Hexahydro-5-hydroxy-1,4a-dimethylnaphthalen-2(3H)-one under Robinson Annulation Conditions

    PubMed Central

    Payette, Joshua N.; Honda, Tadashi; Yoshizawa, Hidenori; Favaloro, Frank G.; Gribble, Gordon W.

    2008-01-01

    We have proposed a pathway of the base–catalyzed reverse vinylogous aldol reaction of (−)-(4aβ,5β)-4,4a,5,6,7,8-hexahydro-5-hydroxy-1,4a-dimethylnaphthalen-2(3H)-one ((−)-8) under Robinson annulation conditions. For confirmation, 4-(2,6-dimethyl-3-oxocyclohex-1-enyl)butanal (11) and 4-(2,6-dimethyl-5-oxocyclohex-1-enyl)butanal (12), both of which potentially produce enolate I, were synthesized regioselectively. Unexpectedly, 11 gave a complex mixture including only a trace amount of (±)-8 (less than 5% yield) under these basic conditions. To the contrary, 12 cleanly afforded (±)-8 in 66% yield. This result provides evidence for our proposed mechanism of the above reaction. PMID:16388674

  7. Cell-autonomous role of TGFβ and IL-2 receptors in CD4+ and CD8+ inducible regulatory T-cell generation during GVHD

    PubMed Central

    Sawamukai, Norifumi; Satake, Atsushi; Schmidt, Amanda M.; Lamborn, Ian T.; Ojha, Priti; Tanaka, Yoshiya

    2012-01-01

    FoxP3+ regulatory T cells (Tregs) suppress GVHD while preserving graft-versus-tumor effects, making them an attractive target for GVHD therapy. The donor-derived Treg pool can potentially be derived from the expansion of preexisting natural Tregs (nTregs) or from de novo generation of inducible Tregs (iTregs) from donor Tconvs in the transplantation recipient. Using an MHC-mismatched model of acute GVHD, in the present study we found that the Treg pool was comprised equally of donor-derived nTregs and iTregs. Experiments using various combinations of T cells from wild-type and FoxP3-deficient mice suggested that both preexisting donor nTregs and the generation of iTregs in the recipient mice contribute to protection against GVHD. Surprisingly, CD8+FoxP3+ T cells represented approximately 70% of the iTreg pool. These CD8+FoxP3+ T cells shared phenotypic markers with their CD4+ counterparts and displayed suppressive activity, suggesting that they were bona fide iTregs. Both CD4+ and CD8+ Tregs appeared to be protective against GVHD-induced lethality and required IL-2 and TGFβ receptor expression for their generation. These data illustrate the complex makeup of the donor-derived FoxP3+ Treg pool in allogeneic recipients and their potential role in protection against GVHD. PMID:22496155

  8. Cell-autonomous role of TGFβ and IL-2 receptors in CD4+ and CD8+ inducible regulatory T-cell generation during GVHD.

    PubMed

    Sawamukai, Norifumi; Satake, Atsushi; Schmidt, Amanda M; Lamborn, Ian T; Ojha, Priti; Tanaka, Yoshiya; Kambayashi, Taku

    2012-06-01

    FoxP3(+) regulatory T cells (Tregs) suppress GVHD while preserving graft-versus-tumor effects, making them an attractive target for GVHD therapy. The donor-derived Treg pool can potentially be derived from the expansion of preexisting natural Tregs (nTregs) or from de novo generation of inducible Tregs (iTregs) from donor Tconvs in the transplantation recipient. Using an MHC-mismatched model of acute GVHD, in the present study we found that the Treg pool was comprised equally of donor-derived nTregs and iTregs. Experiments using various combinations of T cells from wild-type and FoxP3-deficient mice suggested that both preexisting donor nTregs and the generation of iTregs in the recipient mice contribute to protection against GVHD. Surprisingly, CD8(+)FoxP3(+) T cells represented approximately 70% of the iTreg pool. These CD8(+)FoxP3(+) T cells shared phenotypic markers with their CD4(+) counterparts and displayed suppressive activity, suggesting that they were bona fide iTregs. Both CD4(+) and CD8(+) Tregs appeared to be protective against GVHD-induced lethality and required IL-2 and TGFβ receptor expression for their generation. These data illustrate the complex makeup of the donor-derived FoxP3(+) Treg pool in allogeneic recipients and their potential role in protection against GVHD. PMID:22496155

  9. Low Power Resistive Oxygen Sensor Based on Sonochemical SrTi0.6Fe0.4O2.8 (STFO40).

    PubMed

    Stratulat, Alisa; Serban, Bogdan-Catalin; de Luca, Andrea; Avramescu, Viorel; Cobianu, Cornel; Brezeanu, Mihai; Buiu, Octavian; Diamandescu, Lucian; Feder, Marcel; Ali, Syed Zeeshan; Udrea, Florin

    2015-01-01

    The current paper reports on a sonochemical synthesis method for manufacturing nanostructured (typical grain size of 50 nm) SrTi0.6Fe0.4O2.8 (Sono-STFO40) powder. This powder is characterized using X ray-diffraction (XRD), Mössbauer spectroscopy and Scanning Electron Microscopy (SEM), and results are compared with commercially available SrTi0.4Fe0.6O2.8 (STFO60) powder. In order to manufacture resistive oxygen sensors, both Sono-STFO40 and STFO60 are deposited, by dip-pen nanolithography (DPN) method, on an SOI (Silicon-on-Insulator) micro-hotplate, employing a tungsten heater embedded within a dielectric membrane. Oxygen detection tests are performed in both dry (RH = 0%) and humid (RH = 60%) nitrogen atmosphere, varying oxygen concentrations between 1% and 16% (v/v), at a constant heater temperature of 650 °C. The oxygen sensor, based on the Sono-STFO40 sensing layer, shows good sensitivity, low power consumption (80 mW), and short response time (25 s). These performance are comparable to those exhibited by state-of-the-art O2 sensors based on STFO60, thus proving Sono-STFO40 to be a material suitable for oxygen detection in harsh environments. PMID:26205267

  10. Low Power Resistive Oxygen Sensor Based on Sonochemical SrTi0.6Fe0.4O2.8 (STFO40)

    PubMed Central

    Stratulat, Alisa; Serban, Bogdan-Catalin; de Luca, Andrea; Avramescu, Viorel; Cobianu, Cornel; Brezeanu, Mihai; Buiu, Octavian; Diamandescu, Lucian; Feder, Marcel; Ali, Syed Zeeshan; Udrea, Florin

    2015-01-01

    The current paper reports on a sonochemical synthesis method for manufacturing nanostructured (typical grain size of 50 nm) SrTi0.6Fe0.4O2.8 (Sono-STFO40) powder. This powder is characterized using X ray-diffraction (XRD), Mössbauer spectroscopy and Scanning Electron Microscopy (SEM), and results are compared with commercially available SrTi0.4Fe0.6O2.8 (STFO60) powder. In order to manufacture resistive oxygen sensors, both Sono-STFO40 and STFO60 are deposited, by dip-pen nanolithography (DPN) method, on an SOI (Silicon-on-Insulator) micro-hotplate, employing a tungsten heater embedded within a dielectric membrane. Oxygen detection tests are performed in both dry (RH = 0%) and humid (RH = 60%) nitrogen atmosphere, varying oxygen concentrations between 1% and 16% (v/v), at a constant heater temperature of 650 °C. The oxygen sensor, based on the Sono-STFO40 sensing layer, shows good sensitivity, low power consumption (80 mW), and short response time (25 s). These performance are comparable to those exhibited by state-of-the-art O2 sensors based on STFO60, thus proving Sono-STFO40 to be a material suitable for oxygen detection in harsh environments. PMID:26205267

  11. Analysis of purine metabolic enzymes in human CD4 Leu 8- and CD4 Leu 8+ lymphocyte subpopulations.

    PubMed

    Fernandez-Mejia, C; Polmar, S H; Peralta-Zaragoza, O; Madrid-Marina, V

    1993-02-01

    1. Specific activities of adenosine deaminase, purine nucleoside phosphorylase, adenosine kinase, 5'-nucleotidase, S-adenosyl-L-homocysteine hydrolase, AMP deaminase, adenine phosphoribosyl transferase, and hypoxanthine phosphoribosyl transferase were analyzed in human CD4 T-lymphocyte subsets. 2. CD4 Leu 8- (helper/inducer) and CD4 Leu 8+ (suppressor/inducer) subpopulations were obtained by panning or fluorescence activated cell sorting techniques using specific monoclonal antibodies. 3. A 45% decrease of 5'-NT AMP activity in the CD4 Leu 8- cells (suppressor/inducer) compared with CD4 total cell population. 4. No statistical significant differences in enzyme activity were found between the subsets analyzed in other purine enzymes. 5. These results suggest that the distribution of purine metabolic enzymes is homogeneous in CD4 Leu 8- and CD4 Leu 8+ T-lymphocyte subpopulations. PMID:8444317

  12. Developmental and posthatch effects of in ovo exposure to 2,3,7,8-TCDD, 2,3,4,7,8-PECDF, and 2,3,7,8-TCDF in Japanese quail (Coturnix japonica), common pheasant (Phasianus colchicus), and white leghorn chicken (Gallus gallus domesticus) embryos.

    PubMed

    Cohen-Barnhouse, Andrew M; Zwiernik, Matthew J; Link, Jane E; Fitzgerald, Scott D; Kennedy, Sean W; Giesy, John P; Wiseman, Steve; Jones, Paul D; Newsted, John L; Kay, Denise; Bursian, Steven J

    2011-07-01

    An egg injection study was conducted to confirm a proposed model of relative sensitivity of three avian species to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-like chemicals. It was previously reported that the order of species sensitivity to in ovo exposure to TCDD, 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), or 2,3,7,8-tetrachlorodibenzofuran (TCDF) at doses ranging from 0.044 to 37 picomoles (pmol)/g egg was the chicken (Gallus gallus domesticus), common pheasant (Phasianus colchicus), and Japanese quail (Coturnix japonica) based on embryo mortality and hepatic enzyme induction. In the present study, the incidence of developmental deformities, changes in body and relative organ masses, and organ pathology of hatchlings as additional indicators of species sensitivity were assessed; in addition, embryo mortality in the three species was categorized by stage of development. Embryo mortality varied temporally with significant increases generally occurring after organogenesis and just prior to hatching. A significant increase in the percentage of developmental deformities was observed only in Japanese quail exposed to TCDF. Body and relative organ masses of quail, pheasants, and chickens dosed in ovo with TCDD, PeCDF, or TCDF were not consistently affected. Chemical-related pathology occurred only in livers of quail at the greatest doses of each compound. These results indicated that the incidence of developmental deformities, changes in body and relative organ masses and organ pathology could not be used as indicators of species sensitivity or chemical potency. PMID:21509806

  13. Synthesis and characterization of silver and cesium derivatives of Na8[GaSiO4]6(OH)2 sodalite

    NASA Astrophysics Data System (ADS)

    Borhade, A. V.; Wakchaure, S. G.

    2015-03-01

    Gallosilicate hydroxy sodalite, Na8[GaSiO4]6(OH)2 was synthesized at low temperature by hydrothermal method (373 K) and further the sodium ions were partially exchanged with silver and cesium. The obtained products were characterized by IR spectroscopy, X-ray powder diffraction, MAS NMR, TGA and SEM. Parent hydroxy sodalite and its silver and cesium derivatives show cubic symmetry with a space group 3 n. The crystal structures were refined by Rietveld method. The unit cell parameter, a = 8.8527 Å for parent hydroxy sodalite, 8.8342 Å for the silver derivative and 8.9367 Å for cesium one. The 29Si MAS NMR of parent hydroxy sodalite confirms the alternating Ga and Si ordering in sodalite framework, while 23Na MAS NMR shows the effect of cation substitution. The SEM pictures are very regular and show sharp growth for parent sodalite, while the crystal morphology remains nearly same for the silver and cesium derivatives.

  14. Synthesis and Interconversion of V4, V7, and V8 Oxide Clusters: Unexpected Formation of Neutral Heptanuclear Oxido(alkoxido)vanadium(V) Clusters [V7O17(OR)(4,4'-(t)Bubpy)3] (R = Et, MeOC2H4).

    PubMed

    Kodama, Shintaro; Taya, Nobuto; Inoue, Yuta; Ishii, Youichi

    2016-07-01

    The octanuclear oxidovanadium(V) complex [V8O20(4,4'-(t)Bubpy)4] (1; 4,4'-(t)Bubpy = 4,4'-di-tert-butyl-2,2'-bipyridine) was synthesized in multigram-scale quantities by the reaction of VOSO4 with 4,4'-(t)Bubpy in the presence of sodium benzoate under O2. The reaction of 1 with MeOH under air afforded the tetranuclear oxidovanadium(V) complex [V4O8(OMe)4(4,4'-(t)Bubpy)2] (2) selectively. In contrast, treatment of 1 with EtOH or MeOC2H4OH under air gave the heptanuclear oxidovanadium(V) complexes [V7O17(OR)(4,4'-(t)Bubpy)3] (R = Et (3a), MeOC2H4 (3b)) having an unprecedented neutral V7O17(OR) core. Although 3a and 3b are relatively stable in CH2Cl2, slow diffusion of Et2O into the solution of 3a in CH2Cl2 afforded 1 as yellow crystals. Complex 2 was also converted into 1 by recrystallization from CHCl3-CH2Cl2/Et2O. (1)H and (51)V NMR as well as electrospray ionization mass spectrometry studies of the behavior of 2 in CD2Cl2 suggested the formation of the methoxido analogue of 3 (3c, R = Me), which is considered to be an intermediate species in the conversion of 2 to 1. The present results provide a rare example of interconversion among neutral vanadium(V) oxide cluster complexes by changing the solvent systems. PMID:27305344

  15. Optimized anisotropic magnetoelectric response of Fe61.6Co16.4Si10.8B11.2/PVDF/Fe61.6Co16.4Si10.8B11.2 laminates for AC/DC magnetic field sensing

    NASA Astrophysics Data System (ADS)

    Reis, S.; Silva, M. P.; Castro, N.; Correia, V.; Gutierrez, J.; Lasheras, A.; Lanceros-Mendez, S.; Martins, P.

    2016-05-01

    The anisotropic magnetoelectric (ME) effect on a Fe61.6Co16.4Si10.8B11.2/PVDF Fe61.6Co16.4Si10.8B11.2 laminate composite has been used for the development of a magnetic field sensor able to detect both the magnitude and direction of AC and DC magnetic fields. The accuracy (99% for both AC and DC sensors), linearity (92% for the DC sensor and 99% for the AC sensor) and reproducibility (99% for both sensors) indicate the suitability of the sensor for applications. Furthermore, the sensitivity of the Fe61.6Co16.4Si10.8B11.2/PVDF/Fe61.6Co16.4Si10.8B11.2 anisotropic magnetic sensor—15 and 1400 mV Oe‑1 for the DC and AC fields, respectively—are the highest reported in the literature for polymer-based ME materials. Such features, combined with its flexibility, versatility, light weight, low cost and low-temperature fabrication, lead to the suitability of the developed sensor for use in magnetic sensor applications.

  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, 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...

  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, 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...

  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, 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...

  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, 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...

  20. 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...