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Sample records for 1-furfuryl pyrrole characterization

  1. Synthesis, Characterization and Biological Study of Novel Pyrrole Derivatives

    Directory of Open Access Journals (Sweden)

    Rakesh R. Mishra

    2012-07-01

    Full Text Available A facile condensation of aromatic aldehydes with 2-(5-(phenoxymethyl-2-thioxo-1,3,4-oxadiazol-3(2H-ylaceto hydrazide (1 was give the corresponding N’-aryl-2-(5-(phenoxymethyl-2-thioxo-1,3,4-oxadiazol-3(2H-ylacetohydrazide (2a-e in good yield. Cyclo condensation of compounds (2a-e with maleic anhydride yields 2-aryl-5-oxo-1-(2-(5-(phenoxymethyl-2-thioxo-1,3,4-oxadiazol-3(2H-ylacetamido-2,5-dihydro-1H-pyrrole-3-carboxylic acid (3a-e. The structures of these compounds were established on the basis of analytical and spectral data. All the newly synthesized compounds were evaluated for their antibacterial and antifungal activities.

  2. Preparation and characterization of new poly-pyrrole having side chain liquid crystalline moieties

    Energy Technology Data Exchange (ETDEWEB)

    Hosseini, S. Hossein, E-mail: hosseini_sh44@yahoo.com [Department of Chemistry, Faculty of Science and Engineering, Imam Hossein University, Babaee Express Way, Tehran (Iran, Islamic Republic of); Mohammadi, M. [Department of Chemistry, Faculty of Science and Engineering, Imam Hossein University, Babaee Express Way, Tehran (Iran, Islamic Republic of)

    2009-06-01

    We have synthesized a novel liquid-crystalline (LC)-conducting polymer by introducing LC group into pyrrole monomer and polymerizing it with FeCl{sub 3}. The N-substituted pyrrole with LC group (Py-RedII) was prepared by direct reaction of potassium pyrrole salt with 2-[N-ethyl-N-[4-[(4-nitrophenyl)azo]-phenyl]amino]ethyl-3-chloropropionate (RedII). The polymerization of this monomer was successful, giving a conjugated polymer system with liquid crystalline moieties in moderate yield. The polymer obtained was soluble in organic solvents and had a thermotropic liquid crystallinity with mosaic texture characterized by polarizing optical microscopy. Phase transitions, thermal analysis and rheological studies were also evaluated by means of differential scanning calorimetry (DSC), thermogravimetry analysis (TGA) and scanning electron microscopy (SEM), respectively. Spectral properties of poly (2-[N-ethyl-N-[4-[(nitrophenyl)azo]phenyl]amino]ethyl-N-pyrrolyl propionate) (PPy-RedII) were characterized by UV, IR, {sup 1}H NMR, and {sup 13}C NMR spectroscopies. The photoluminescence spectrum of the film showed that maximum photoluminescence peak emission is located at 437 nm, corresponding to the photon energy of 2.5 eV. Electrical conductivity of PPy-RedII was studied by the four-probe method and produced a conductivity of 7.5 x 10{sup -4} S cm{sup -1}.

  3. Synthesis and Physical Characterization of Carbon Nano tubes Coated by Conducting Poly pyrrole

    International Nuclear Information System (INIS)

    This study describes the preparation of poly pyrrole multi walled carbon nano tube (PPy/ MWNT) composites by in situ chemical oxidative polymerization. Various ratios of functionalized MWNTs are dispersed in the water, and PPy are then synthesized via in-situ chemical oxidative polymerization on the surface of the carbon nano tubes. The morphology of the resulting complex nano tubes (MWNT-PPY) was characterized by scanning electron microscopy (SEM). The conductivity of each composite showed a maximum in the temperature scale of 120- 160 degree Celsius and then decreased dramatically with the increase of temperature. (author)

  4. -pyrrole substituted porphyrin-pyrene dyads using vinylene spacer: Synthesis, characterization and photophysical properties

    Indian Academy of Sciences (India)

    P Silviya Reeta; Ravi Kumar Kanaparthi; L Giribabu

    2013-03-01

    We have designed and synthesized donor-acceptor conjugates having donor pyrene at the pyrrole- position of either free-base porphyrin or Zn(II) porphyrin using vinylene spacer. Both the dyads have been completely characterized by elemental analysis,MALDI-MS, UV-Vis., and fluorescence (steady state and timeresolved) spectroscopies as well as cyclic voltammetry. The absorption maxima of both dyads are red-shifted by 8-12 nm. The ground state properties showed that there exist minimum - interaction between the aromatic subunits of these D-A systems. Quenched emission was observed in both the dyads when excited at 290 nm. The quenched emission explained in terms of intramolecular excitation energy transfer competes with the photo-induced electron transfer reaction in these D-A system.

  5. Synthesis and spectroscopic characterization of pyrrole-2,3-diones and their following reactions with 1,2-aromatic diamines

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    İrfan Koca

    2012-01-01

    Full Text Available 4-aroyl-5-aryl-2,3-furandiones and N,N-dialkyl urea combine with loss of water yielding the pyrrole-2,3-dione derivatives in moderate yields (47-68%. Then, these compounds were converted into 2(1H-quinoxalinones with various 1,2-phenylenediamines. The structures and characterizations of the synthesized compounds were established by the 1H- and 13C-NMR, IR and elemental analysis.

  6. Conjugated polymers with pyrrole as the conjugated bridge: synthesis, characterization, and two-photon absorption properties.

    Science.gov (United States)

    Li, Qianqian; Zhong, Cheng; Huang, Jing; Huang, Zhenli; Pei, Zhiguo; Liu, Jun; Qin, Jingui; Li, Zhen

    2011-07-14

    The synthesis, one- and two-photon absorption (2PA) and emission properties of two novel pyrrole-based conjugated polymers (P1 and P2) are reported. They emitted strong yellow-green and orange fluorescence with fluorescent quantum yields (Φ) of 46 and 33%, respectively. Their maximal 2PA cross sections (δ) measured by the two-photon-induced fluorescence method using femtosecond laser pulses in THF were 2392 and 1938 GM per repeating unit, respectively, indicating that the 2PA chromophores consisting of the triphenylamine with nonplanar structure as the donor and electron-rich pyrrole as the conjugated bridge could be the effective repeating units to enhance the δ values.

  7. Synthesis, characterization, molecular docking and biological studies of self assembled transition metal dithiocarbamates of substituted pyrrole-2-carboxaldehyde.

    Science.gov (United States)

    Nami, Shahab A A; Ullah, Irfan; Alam, Mahboob; Lee, Dong-Ung; Sarikavakli, Nursabah

    2016-07-01

    A series of self assembled 3d transition metal dithiocarbamate, M(pdtc) [where M=Mn(II), Fe(II), Co(II), Ni(II) and Cu(II)] have been synthesized and spectroscopically characterized. The bidentate dithiocarbamate ligand Na2pdtc (Disodium-1,4-phenyldiaminobis (pyrrole-1-sulfino)dithioate) was prepared by insertion reaction of carbondisulfide with Schiff base, N,N'-bis-(1H-pyrrol-2-ylmethylene)-benzene-1,4-diamine (L1) in basic medium. The simple substitution reaction between the metal halide and Na2pdtc yielded the title complexes in moderate yields. However, the in situ procedure gives high yield with the formation of single product as evident by TLC. Elemental analysis, IR, (1)H and (13)C NMR spectra, UV-vis., magnetic susceptibility and conductance measurements were done to characterize the complexes, M(pdtc). All the evidences suggest that the complexes have tetrahedral geometry excepting Cu(II) which is found to be square planar. A symmetrical bidentate coordination of the dithiocarbamato moiety has been observed in all the complexes. The conductivity data show that the complexes are non-electrolyte in nature. The anti-oxidant activity of the ligand, Na2pdtc and its transition metal complexes, M(pdtc) have been carried out using DPPH and Cu(pdtc) was found to be most effective. The anti-microbial activity of the Na2pdtc and M(pdtc) complexes have been carried out and on this basis the molecular docking study of the most effective complex, Cu(pdtc) has also been reported. PMID:27197060

  8. Characterization of poly pyrrole/montmorillonite electro polymerised onto Pt; Caracterizacao de filmes PPy/montmorilonita eletropolimerizados sobre Pt

    Energy Technology Data Exchange (ETDEWEB)

    Castagno, K.R.L., E-mail: katiarlc@pelotas.ifsul.edu.b [Instituto Federal Sul-rio-grandense (IFSul), RS (Brazil). Dept. de Quimica; Azambuja, D.S.; Dalmoro, V.; Mauller, R.S. [Universidade Federal do Rio Grande do Sul (UFRGS), Pelotas, RS (Brazil). Inst. de Quimica

    2010-07-01

    In this study films of polypyrrole/montmorillonite (PPy/MT) were electropolymerized on platinum in order to evaluate the performance of this technique in the preparation of nanocomposite materials and to determine the thermal properties and conductivity of the composites. The films were synthesized from a solution containing pyrrole, dodecylbenzene sulfonate, acid and two types of clays: montmorillonite-Na + (MT-Na) and montmorillonite-30B (MT-M). The characterization of the films we have used FT-IR, TEM, XRD, TGA, DSC and resistivity measurement by the four-point van der Pauw method. The study showed that the adopted method of exfoliation and the electropolymerization method used, allows obtaining nanocomposite materials. Analyses of FT-IR, TEM and XRD show that the clays are exfoliated in the polymer matrix. Thermal analysis of the films indicates that the addition of clay reflects an enhancement in the thermal properties of the matrix of PPy, but decreases the conductivity of the same. (author)

  9. Electrochemical synthesis of Poly[3, 4-Propylenedioxythiophene-co-N-Phenylsulfonyl Pyrrole]: Morphological, electrochemical and spectroscopic characterization

    Directory of Open Access Journals (Sweden)

    2011-06-01

    Full Text Available Electroactive random copolymers of 3,4-Propylenedioxythiophene (ProDOT and N-Phenylsulfonyl Pyrrole (PSP were electrochemically synthesized on single carbon fiber microelectrode (SCFME by cyclic voltammetry (CV. Fourier Transform Infrared-Attenuated Total Reflectance (FTIR-ATR measurements indicate the inclusion of PSP into the copolymer structure. The influence of feed ratios on the copolymers was studied by CV and electrochemical impedance spectroscopy (EIS and equivalent circuit modelling (ECM. The morphologies and film thicknesses of copolymers were characterized by scanning electron microscopy (SEM and atomic force microscopy (AFM. The results have shown that the principal changes in morphology, conductivity, porous nature and thickness of Poly(ProDOT-co-PSP film depend on the concentration of PSP. The strong electron-withdrawing sulfonyl group substitution on PSP significantly inhibited electrochemical copolymerization. Semicircular characteristics at Nyquist plots reflected an increasing trend with the increase of PSP concentration in the feed at high frequency. The semicircular characteristic of the copolymer film is useful for the bioelectrochemical sensor applications.

  10. Synthesis, characterization and anticancer studies of new steroidal oxadiazole, pyrrole and pyrazole derivatives

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    Shamsuzzaman

    2015-07-01

    Full Text Available In the present study steroidal derivatives, 3β-[5′-mercapto-1′,3′,4′-oxadiazole-2-yl]methoxy cholest-5-ene 2, 3β-[2′,5′-dimethylpyrrole-1-yl]aminocarbonylmethoxycholest-5-ene 3 and 3β-[3′,5′-dimethyl pyrazole-1-yl]carbonylmethoxycholest-5-ene 4 have been synthesized from cholest-5-en-3β-O-acetyl hydrazide 1 using CS2/KOH, acetonyl acetone and acetyl acetone, respectively as reagents and are characterized by IR, 1H NMR,13C NMR, MS and elemental analysis. Compounds 2–4 were also evaluated for anticancer activity against human leukemia cell line (HL-60 by MTT assay and compound 4 displayed the promising behavior by showing better anticancer activity.

  11. The Oxidation of Pyrrole.

    Science.gov (United States)

    Howard, James K; Rihak, Kieran J; Bissember, Alex C; Smith, Jason A

    2016-01-01

    The dearomatization of heterocycles has been a powerful means for producing functional molecules in synthesis. In the case of pyrroles, reductive methods (such as the Birch reduction) have been most widely exploited, while oxidative methods are generally dismissed as too difficult or unpredictable to be useful. However, since the early twentieth century considerable research has been carried out on the controlled oxidation of pyrroles to give highly functionalized products, using a variety of oxidants. This review presents a summary of all work up until the present day in the area of pyrrole oxidation, looking at the use of peroxide, singlet oxygen, hypervalent iodine reagents, a range or organic and inorganic oxidants, and electrochemical approaches. It also offers some perspective on the potential future role of pyrrole oxidation in synthesis. PMID:26294175

  12. Characterization of multi-walled carbon nanotube electrodes functionalized by electropolymerized tris(pyrrole-ether bipyridine) ruthenium (II)

    Energy Technology Data Exchange (ETDEWEB)

    Le Goff, Alan; Holzinger, Michael [Departement de Chimie Moleculaire UMR-5250, ICMG FR-2607, CNRS Universite Joseph Fourier, BP-53, 38041 Grenoble (France); Cosnier, Serge, E-mail: Serge.Cosnier@ujf-grenoble.f [Departement de Chimie Moleculaire UMR-5250, ICMG FR-2607, CNRS Universite Joseph Fourier, BP-53, 38041 Grenoble (France)

    2011-04-01

    We synthesized new electropolymerizable [Ru(bpy){sub n}L{sub m}](PF{sub 6}){sub 2} (L = 4,4 bis(3-pyrrol-1-ylpropyloxy)bipyridyl) derivatives. The introduction of electron donating ether groups in the bipyridine ligand induced a negative shift of the Ru(III)/(II) redox couple. The electrochemical behavior of complex Ru1 (n = 2, m = 1) and complex Ru2 (n = 0, m = 3) were compared using platinum and Multi-Walled Carbon Nanotube (MWCNT) electrode. Higher polymerization yields and surface concentrations were obtained at MWCNT electrodes. Furthermore, MWCNT electrodes increase polymer permeability and decrease the charge trapping phenomenon involved in the oxidation and reduction of the polypyrrolic skeleton of the Ru(II) functionalized polymers.

  13. Flexible supercapacitor based on electrochemically synthesized pyrrole formyl pyrrole copolymer coated on carbon microfibers

    Science.gov (United States)

    Gholami, Mehrdad; Moozarm Nia, Pooria; Narimani, Leila; Sokhakian, Mehran; Alias, Yatimah

    2016-08-01

    The main objective of this work is to prepare a flexible supercapacitor using electrochemically synthesized pyrrole formyl pyrrole copolymer P(Py-co-FPy) coated on the carbon microfibers. Due to difficulties of working with carbon microfibers, glassy carbon was used to find out optimized conditions by varying mole ratio of pyrrole and formyl pyrrole monomers on the capacitance value. The prepared electrodes were characterized using Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscope (FESEM), Brunauer-Emmett-Teller (BET) analysis, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Then the X-ray photoelectron spectroscopy (XPS) was used to characterize the optimized electrode. The specific capacitance is calculated using cyclic voltammetry, charge/discharge method, and impedance spectroscopy. The charge/discharge study reveals that the best specific capacitance is estimated to be 220.3 mF cm-2 for equal mole fraction of pyrrole and formyl pyrrole Py (0.1)-FP (0.1) at discharge current of 3 × 10-4 A. This optimized electrode keeps about 92% of its capacitance value in high current of discharging. The specific capacitances calculated by all the mentioned methods are in agreement with each other. Finally, the found optimized conditions were successfully applied to produce a flexible supercapacitor on the surface of carbon microfibers.

  14. Characterization of electro-conductive fabrics prepared by in situ chemical and electrochemical polymerization of pyrrole onto polyester fabric

    Energy Technology Data Exchange (ETDEWEB)

    Maiti, Syamal; Das, Dipayan; Sen, Kushal, E-mail: kushal@textile.iitd.ernet.in

    2014-09-15

    Highlights: • Surface resistivity of the fabrics decreased rapidly with an increase in add-on. • Add-on and resistivity were not correlated below a resistivity value of about 200 Ω. • Higher add-on but lower surface roughness resulted in lower surface resistivity. • The voltage–current and voltage–temperature behaviours were found to be non-linear. • Electro-conductive fabric exhibited 98% electromagnetic shielding efficiency. - Abstract: This paper reports a study on electro-conductive fabrics prepared by a combined in situ chemical and electrochemical polymerization of pyrrole. Specific observations are made to establish the roles of add-on and surface roughness on the surface resistivity of the electro-conductive fabrics. The performance characteristics of the fabrics are reported in terms of electrical conductivity, voltage–current and voltage–temperature characteristics and electromagnetic interference (EMI) shielding capability. The surface resistivity of the fabric was found to be as low as 11.79 Ω. The voltage–current profile of the fabric is observed to be non-ohmic as well as the voltage–temperature curve is found to be exponential. The EMI shielding efficiency of the fabric was found to be about 98%.

  15. Synthesis and characterization of new electron-withdrawing moiety thieno[2,3-c]pyrrole-4,6-dione-based molecules for small molecule solar cells

    DEFF Research Database (Denmark)

    Fu, Lei; Pan, Hongbin; Larsen-Olsen, Thue Trofod;

    2013-01-01

    –π–donor–π–acceptor type end-capped with thieno[2,3-c]pyrrole-4,6-dione (TPD) units for small molecule solar cells have been prepared through coupling of dithienosilole and TPD units bridged with thienylene and bithienylene. They are soluble in common organic solvents and show an interesting absorption. These small...

  16. Morphology and electrical properties of electrochemically synthesized pyrrole-formyl pyrrole copolymer

    Science.gov (United States)

    Gholami, Mehrdad; Nia, Pooria Moozarm; Alias, Yatimah

    2015-12-01

    A direct electrochemical copolymerization of pyrrole-formyl pyrrole (Py-co-FPy) was carried out by oxidative copolymerization of formyl pyrrole and pyrrole in LiClO4 aqueous solution through galvanostatic method. The (Py-co-FPy) copolymer was characterized using Fourier-transform infrared spectroscopy (FT-IR), field emission scanning electron microscope (FESEM), energy-filtering transmission electron microscope (EFTEM), thermal gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The FESEM images showed that the synthesized copolymer had a hollow whelk-like helixes structure, which justifies the enhancement of charge transportation through the copolymer film. Cyclic voltammetry studies revealed that the electrocatalytic activity of synthesized copolymer has improved and the surface coverage in copolymer enhanced 1.6 times compared to polypyrrole alone. Besides, (Py-co-FPy) copolymer showed 2.5 times lower electrochemical charge transfer resistance (Rct) value in impedance spectroscopy. Therefore, this copolymer has a strong potential to be used in several applications such as sensor applications.

  17. Synthesis, characterization and computational study on ethyl 4-(3-Furan-2yl-acryloyl)-3,5-dimethyl-1H-pyrrole-2-carboxylate

    Science.gov (United States)

    Singh, R. N.; Rawat, Poonam; Sahu, Sangeeta

    2014-11-01

    As part of study on pyrrole derivatives, we have synthesized a pyrrole chalcone derivative: ethyl 4-(3-Furan-2yl-acryloyl)-3,5-dimethyl-1H-pyrrole-2-carboxylate (EFADPC) by aldol condensation of ethyl 3, 5-dimethyl-4-actyl-1H-pyrrole-2-carboxylate with furan-2-carbaldehyde in the presence of strong hydroxyl base as catalyst. The product EFADPC has been confirmed by spectroscopic (FT-IR, 1H NMR, and UV-visible) analyses. Quantum chemical calculation also provides good correlation with experimental data. The molecular electrostatic potential surface (MEP), natural bond orbital interactions (NBO), electronic descriptors, quantum theory of atoms' in molecules (QTAIM) and experimental FT-IR spectrum have been used to predict the sites and nature of interactions which indicate that the dimer formation with multiple interactions through Nsbnd H···O and Csbnd H···O. The vibrational analysis shows red shifts in νNsbnd H and νCdbnd O as result of dimer formation. The binding energy of dimer is calculated as 13.82, 15.24 kcal/mol using DFT, QTAIM analysis, respectively. The result of ellipticity confirms the existence of resonance assisted hydrogen bonds (RAHB) in dimer. The MEP and local reactivity descriptors analyses have been performed and the results indicate that carbonyl carbon and β-carbon of chalcone frame have been prone to nucleophilic attack and lead to large number of heterocyclic compounds such as oxirane, oxazoles, pyrazoles, pyridines, pyrimidines, and pyran.

  18. Polycondensation of pyrrole and benzaldehyde catalyzed by Maghnite–H+

    Directory of Open Access Journals (Sweden)

    2007-07-01

    Full Text Available Rapid synthesis of poly[(pyrrole-2,5-diyl-co-(benzylidene] was achieved under microwave irradiation via the condensation of pyrrole and benzaldehyde in 1,2-dichloroethane using acid exchanged montmorillonite clay called Maghnite–H+ (Mag–H+ as an efficient catalyst. The effect of the amount of catalyst and of time on the polymerization yield and on the viscosity of the polymers was studied. Compared with conventional static interfacial polymerization, the microwave-radiation polymerization reaction proceeded rapidly and was completed within 35 s. The conjugated polymer was characterized by means of 1H-NMR, X-ray diffraction, FT-IR spectroscopy and AFM. The X-ray data showed the presence of a backbone form of the [(pyrrole-2,5-diyl-co-(benzylidene] formed.

  19. Construction of a monoanionic S,N,S-pincer ligand with a pyrrole core by sequential [1,2] phospho-Fries rearrangement. Characterization of palladium and silver coordination complexes

    NARCIS (Netherlands)

    Fraix, A.; Lutz, M.; Spek, A.L.; Klein Gebbink, R.J.M.; van Koten, G.; Salaun, J. -Y; Jaffrès, P. -A

    2010-01-01

    The synthesis of an S,NH,S-pincer ligand possessing a pyrrole core and two O,O-diethylthiophosphonyl groups to design PS lateral coordination sites is reported. The synthetic procedure to produce this ligand makes use of the nitrogen atom of the pyrrole heterocycle to successively functionalize the

  20. Synthesis of poly[(pyrrole-2,5-diyl)-co-(4-hydroxylbenzylidene)] catalysed by Maghnite– H+

    OpenAIRE

    Bouhadjar Larbi; Aïcha Hachemaoui; Yahiaoui Ahmed; Bouchama Abdelghani; Chikh Karime; Belbachir Mohamed

    2014-01-01

    Rapid synthesis of poly[(pyrrole-2,5-diyl)-co-(4-hydroxylbenzylidene)] was achieve via the condensation of pyrrole and 4-hydroxylbenzylidene in dichloromethane using acid exchanged montmorillonite clay called Maghnite– H+ (Mag–H+) as an efficient catalyst The conjugated polymer was characterized by means of 1H-NMR, UV-visible, FT-IR spectroscopy and TGA.

  1. Study on the nature of interaction of pyrrole with various hydrides

    International Nuclear Information System (INIS)

    Graphical abstract: The equilibrium geometries of the pyrrole-HnX (X=F, O, N, Cl, S and P) complexes are shown in above figure. These geometries are classified as N-H...X type and H-π-type (also referred to in this paper as geometry types I and II, respectively). The N-H...X type geometry features a hydrogen bond formed between the hydrogen atom of pyrrole and X atom of HnX, and has C1 symmetry. The π-type geometry is characterized by an H-π bond formed between a hydrogen atom of HnX and the π-electron system of the aromatic ring, and has C1 symmetry. For the pyrrole-HF, H2O, NH3, H2S and -PH3 complexes have N-H...X type and π-type. For the pyrrole-HCl complexes have only H-π-type. Display Omitted Highlights: → We investigated the intermolecular interaction of pyrrole with the various hydrides. → There are N-H...X and H-π-type hydrogen-bonding complexes. → With the exception of pyrrole-H2O and pyrrole-NH3 complexes, all of the other pyrrole-HnX complexes favors π-type H-bonding. → The electrostatic and dispersion interactions dominate the H-π-type complexes. - Abstract: Equilibrium geometries, interaction energies, atomic charge, and charge transfer for the N-H...X and H-π-type hydrogen-bonding complexes between pyrrole and various hydrides HnX (X=F, O, N, Cl, S, and P) were studied at the MP2/aug-cc-pVDZ level. With the exception of pyrrole-H2O and pyrrole-NH3 complexes, all of the other pyrrole-HnX complexes favors π-type H-bonding. To further study the nature of the π-type H-bonding, an SAPT (the symmetry adapted perturbation theory) energy decomposition analysis was carried out and the results indicate that the electrostatic and dispersion interactions dominate the H-π-type complexes.

  2. Poly [(pyrrole-2, 5-diyl) co(4-Nitro benzylidene)]: A new synthetic approach and electronic properties

    Science.gov (United States)

    Gherras, H.; Hachemaoui, A.; Yahiaoui, A.; Belbachir, M.; Belfedal, A.

    2012-02-01

    A new poly (heteroarylene methylene) containing one to four α-pyrrole rings alternating with an sp3-carbon atom in the main chain were synthesized and characterized. The synthesized poly [(pyrrole-2, 5-diyl)-co-(4-nitrobenzylidene)] was found to be highly dehydrogenated, thus resulting in black materials with conjugated segments larger than a single pyrrole ring. The conjugated polymers containing alternating aromatic and quinoid heteroarylene moieties in the main chain were prepared by polycondensation of 4-nitrobenzaldehyde and pyrrole catalysed by Maghnite-H+. The new polymer is useful precursors to small-bandgap polymers based on poly (heteroarylene methines) and is also useful model system for the investigation of the effects of π-conjugation length on the electronic and optical properties of conjugated polymers.

  3. Synthesis of hollow poly(aniline-co-pyrrole)-Fe3O4 composite nanospheres and their microwave absorption behavior

    OpenAIRE

    Zhu, Yao-Feng; Zhang, Li; Natsuki, Toshiaki; Fu, Ya-Qin; Ni, Qing-Qing

    2012-01-01

    Hollow poly(aniline-co-pyrrole)-Fe3O4 (HPAP-Fe3O4) nanospheres with significant electromagnetic properties were successfully prepared via the oxidative polymerization of a mixture of aniline and pyrrole in the presence of a magnetic fluid, using a non-ionic surfactant as a template. The products were characterized by field emission scanning electron microscopy, transmission electron microscopy. Fourier transform infrared spectroscopy, X-ray powder diffraction, thermogravimetric analysis and X...

  4. Synthesis of poly[(pyrrole-2,5-diyl-co-(4-hydroxylbenzylidene] catalysed by Maghnite– H+

    Directory of Open Access Journals (Sweden)

    Bouhadjar Larbi

    2014-01-01

    Full Text Available Rapid synthesis of poly[(pyrrole-2,5-diyl-co-(4-hydroxylbenzylidene] was achieve via the condensation of pyrrole and 4-hydroxylbenzylidene in dichloromethane using acid exchanged montmorillonite clay called Maghnite– H+ (Mag–H+ as an efficient catalyst The conjugated polymer was characterized by means of 1H-NMR, UV-visible, FT-IR spectroscopy and TGA.

  5. A new pyrrole alkaloid from seeds of Castanea sativa.

    Science.gov (United States)

    Hiermann, Alois; Kedwani, Samir; Schramm, Hans Wolfgang; Seger, Christoph

    2002-02-01

    A new pyrrole alkaloid, methyl-(5-formyl-1H-pyrrole-2-yl)-4-hydroxybutyrate (1), was isolated from sweet chestnut seeds and its structure elucidated on the basis of data from NMR spectroscopy and by comparison with synthetic analogues.

  6. Electrophilic surface sites as precondition for the chemisorption of pyrrole on GaAs(001) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Bruhn, Thomas [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstr.36, D-10623 Berlin (Germany); Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V., Albert-Einstein-Str.9, 12489 Berlin (Germany); Fimland, Bjørn-Ove [Department of Electronics and Telecommunications, Norwegian University of Science and Technology, NO-7491 Trondheim (Norway); Vogt, Patrick, E-mail: patrick.vogt@tu-berlin.de [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstr.36, D-10623 Berlin (Germany)

    2015-03-14

    We report how the presence of electrophilic surface sites influences the adsorption mechanism of pyrrole on GaAs(001) surfaces. For this purpose, we have investigated the adsorption behavior of pyrrole on different GaAs(001) reconstructions with different stoichiometries and thus different surface chemistries. The interfaces were characterized by x-ray photoelectron spectroscopy, scanning tunneling microscopy, and by reflectance anisotropy spectroscopy in a spectral range between 1.5 and 5 eV. On the As-rich c(4 × 4) reconstruction that exhibits only nucleophilic surface sites, pyrrole was found to physisorb on the surface without any significant modification of the structural and electronic properties of the surface. On the Ga-rich GaAs(001)-(4 × 2)/(6 × 6) reconstructions which exhibit nucleophilic as well as electrophilic surface sites, pyrrole was found to form stable covalent bonds mainly to the electrophilic (charge deficient) Ga atoms of the surface. These results clearly demonstrate that the existence of electrophilic surface sites is a crucial precondition for the chemisorption of pyrrole on GaAs(001) surfaces.

  7. Electrophilic surface sites as precondition for the chemisorption of pyrrole on GaAs(001) surfaces

    International Nuclear Information System (INIS)

    We report how the presence of electrophilic surface sites influences the adsorption mechanism of pyrrole on GaAs(001) surfaces. For this purpose, we have investigated the adsorption behavior of pyrrole on different GaAs(001) reconstructions with different stoichiometries and thus different surface chemistries. The interfaces were characterized by x-ray photoelectron spectroscopy, scanning tunneling microscopy, and by reflectance anisotropy spectroscopy in a spectral range between 1.5 and 5 eV. On the As-rich c(4 × 4) reconstruction that exhibits only nucleophilic surface sites, pyrrole was found to physisorb on the surface without any significant modification of the structural and electronic properties of the surface. On the Ga-rich GaAs(001)-(4 × 2)/(6 × 6) reconstructions which exhibit nucleophilic as well as electrophilic surface sites, pyrrole was found to form stable covalent bonds mainly to the electrophilic (charge deficient) Ga atoms of the surface. These results clearly demonstrate that the existence of electrophilic surface sites is a crucial precondition for the chemisorption of pyrrole on GaAs(001) surfaces

  8. Pyrrole-added Fe2O3 films by ultrasonic spray pyrolisis

    OpenAIRE

    Carlos Torres Frausto; Alejandro Avila Garcia

    2009-01-01

    Fe2O3 thin films were grown by Ultrasonic Spray Pyrolisis from a 0.05 aqueous solution of FeCl3 added with a small amount of pyrrole monomer. Films at different substrate temperature and pyrrole content were grown. They were characterized by using x-ray diffraction (XRD), infrared spectroscopy (FTIR) and atomic force microscopy (AFM). Results indicated that at low substrate temperature (approximately 200ºC) the films mainly resemble the polypyrrole structure. At higher temperatures up to 400...

  9. Tris[2-(pyrrol-2-ylmethyleneaminoethyl]amine

    Directory of Open Access Journals (Sweden)

    Hongbing Fu

    2008-03-01

    Full Text Available The title compound, C21H27N7, was synthesized by reaction of tris(2-aminoethylamine and pyrrole-2-carbaldehyde in ethanol at room temperature. The structure is stabilized by intra- and intermolecular C—H...N and N—H...N hydrogen-bonding interactions.

  10. The electrochemical synthesis of poly(pyrrole-co-o-anisidine) on 3102 aluminum alloy and its corrosion protection properties

    Energy Technology Data Exchange (ETDEWEB)

    Mert, B. Dogru, E-mail: bdogru@cu.edu.tr [Cukurova University, Science and Letters Faculty, Chemistry Department, 01330 Balcali, Adana (Turkey); Yazici, B. [Cukurova University, Science and Letters Faculty, Chemistry Department, 01330 Balcali, Adana (Turkey)

    2011-02-15

    Research highlights: {yields} The electrochemical synthesis of strongly adherent, uniform polypyrrole (PPy) and poly(pyrrole-co-o-anisidine) coatings were successfully achieved on 3102 aluminum alloy from 0.1 M monomer (pyrrole and pyrrole:o-anisidine, 8:2) containing oxalic acid by means of the cyclic voltammetry technique. {yields} The results were showed that the water permeation of copolymer coating is lower than PPy. {yields} This study was showed that copolymer is suitable coating for protection of 3102 Al alloy against corrosion. - Abstract: The electrochemical syntheses of polypyrrole (PPy) and poly(pyrrole-co-o-anisidine) were achieved on 3102 aluminum alloy (Al) from 0.1 M monomer (pyrrole:o-anisidine, 8:2) containing 0.4 M oxalic acid solution using the cyclic voltammetry technique. The synthesized films were characterized by FT-IR spectroscopy. The thermal stability of films was determined by thermogravimetric analysis (TGA) technique. Surface morphologies were characterized by scanning electron microscope (SEM) images. The potential of zero charge (pzc) of Al was determined using electrochemical impedance spectroscopy (EIS). The corrosion behavior of samples was investigated with open circuit potential (E{sub ocp})-time, EIS, and anodic polarization techniques. It was found that copolymer coated Al provides better barrier property against of corrosion in 3.5% NaCl solution.

  11. Preparation of conductive membranes using poly pyrrole

    International Nuclear Information System (INIS)

    Conductive membranes show many benefits including fouling reduction for feeds containing ionic species. These membranes may be prepared either by conductive polymers or coating of the surfaces of non-conductive membranes with conductive polymer. In this research, the commercial micro filtration GVHP membrane manufactured from PVDF was coated with poly pyrrole using two different techniques. The conductivity of the prepared membranes was measured. In this paper, effects of various factors including concentration of the solutions, oxidizing agents, time for leaving the support in the solutions, support type and temperature on membrane conductivity were investigated

  12. Revisiting the relaxation dynamics of isolated pyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Montero, Raúl; Ovejas, Virginia; Fernández-Fernández, Marta; Longarte, Asier, E-mail: asier.longarte@ehu.es [Departamento de Química Física, Universidad del País Vasco (UPV/EHU), Apart. 644, 48080 Bilbao (Spain); Peralta Conde, Álvaro [Centro de Láseres Pulsados (CLPU), Edificio M3, Parque Científico, 37185 Villamayor (Spain)

    2014-07-07

    Herein, the interpretation of the femtosecond-scale temporal evolution of the pyrrole ion signal, after excitation in the 267–217 nm interval, recently published by our group [R. Montero, A. Peralta Conde, V. Ovejas, M. Fernández-Fernández, F. Castaño, J. R. Vázquez de Aldana, and A. Longarte, J. Chem. Phys.137, 064317 (2012)] is re-visited. The observation of a shift in the pyrrole{sup +} transient respect to zero delay reference, initially attributed to ultrafast dynamics on the πσ{sup *} type state (3s a{sub 1} ← π 1a{sub 2}), is demonstrated to be caused by the existence of pump + probe populated states, along the ionization process. The influence of these resonances in pump-prone ionization experiments, when multi-photon probes are used, and the significance of a proper zero-time reference, is discussed. The possibility of preparing the πσ{sup *} state by direct excitation is investigated by collecting 1 + 1 photoelectron spectra, at excitation wavelengths ranging from 255 to 219 nm. No conclusive evidences of ionization through this state are found.

  13. Effect of Pyrrole and N-Methylpyrrole Coatings on Corrosion Resistance of Mild Steel

    Institute of Scientific and Technical Information of China (English)

    AliAshrafi; M.A.Golozarl; S.Mallakpour; AliGhasemi

    2004-01-01

    Electrochemical polymerizations of various ratios of pyrrole and methylpyrrole monomers were performed in aqueous toluene-4-sulfinic acid sodium salt (T4SNa) electrolyte, using galvanostatic method, pH of electrolyte was adjusted by p-toluene sulfonic acid (PTSA). In order to prevent corrosion of mild steel substrates during coating deposition, specimens were pretreated in 0.5M oxalic acid solution, employing galvanostatic method. This would passivate the steel substrate and facilitate the coating process as well. Corrosion resistance of coated substrates was investigated in 1M NaCl solution using Tafel polarization technique. In addition, using scanning electron microscopy (SEM), morphological characterization of coatings produced, was investigated. Regarding the corrosion characteristics, results obtained revealed that the ratio of 1 to 1(Pyrrole/Methylpyrrole) could play an important role.

  14. Living on pyrrolic foundations - Advances in natural and artificial bioactive pyrrole derivatives.

    Science.gov (United States)

    Domagala, Anna; Jarosz, Tomasz; Lapkowski, Mieczyslaw

    2015-07-15

    Pyrrole, a simple heterocyclic system, is an important building block for numerous biologically active compounds both natural and synthetic in origin, which boast an immense array of qualities, baleful and beneficial alike. The latter have given rise to a bountiful variety of pyrrole-based drugs, with many more being designed, developed and applied each year, as evidenced by the amount of entries in the Cambridge Structural Database skyrocketing from about six hundred in 2004 to more than a thousand over the course of the last decade. Particularly important in light of the ever-encroaching menace of drug-resistant bacteria, the vast progress in the field necessitates a sound organisational framework and summary - a task, to which we contribute this summary and checklist of the most recent developments, indicating the classes of compounds, which have attracted the most significant research attention. PMID:26087028

  15. Pyrrole-Pyridine and Pyrrole-Naphthyridine Hosts for Anion Recognition

    Directory of Open Access Journals (Sweden)

    M. Angeles García

    2015-05-01

    Full Text Available The association constants of the complexes formed by two hosts containing pyrrole, amide and azine (pyridine and 1,8-naphthyridine groups and six guests, all monoanions (Cl−, CH3CO2−, NO3−, H2PO4−, BF4−, PF6−, have been determined using NMR titrations. The X-ray crystal structure of the host N2,N5-bis(6-methylpyridin-2-yl-3,4-diphenyl-1H-pyrrole- 2,5-dicarboxamide (1 has been solved (P21/c monoclinic space group. B3LYP/6-31G(d,p and calculations were carried out in an attempt to rationalize the trends observed in the experimental association constants.

  16. Electrochemical impedance of poly(9-tosyl-9H-carbazole-co-pyrrole) electrocoated carbon fiber

    Energy Technology Data Exchange (ETDEWEB)

    Ates, Murat; Uludag, Nesimi [Department of Chemistry, Faculty of Arts and Sciences, Namik Kemal University, Degirmenalti Campus, 59030, Tekirdag (Turkey); Sarac, A. Sezai, E-mail: sarac@itu.edu.tr [Department of Chemistry, Polymer Science and Technology, Istanbul Technical University, Maslak, 34469, Istanbul (Turkey)

    2011-05-16

    Research highlights: {yields} Impedance study of poly(9-tosyl-9H-carbazole-co-pyrrole) electrocoated carbon fiber. {yields} Copolymer of 9-tosyl-9H-carbazole and pyrrole were electrocoated on carbon fiber. {yields} Impedance spectroscopy and circuit models of poly(9-tosyl-9H-carbazole-co-pyrrole). - Abstract: In this paper, copolymer of 9-tosyl-9H-carbazole (TCz) and pyrrole (Py) comonomers were electrochemically deposited onto carbon fiber micro electrode (CFME) as an active electrode material. An electrochemical impedance study on the prepared electrodes is reported. Poly(TCz-co-Py)/CFME is characterized by cyclic voltammetry (CV), Fourier transform infrared reflectance-attenuated total reflection spectroscopy (FTIR-ATR), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), and electrochemical impedance spectroscopy (EIS). Capacitive behaviors of modified CFMEs were defined via Nyquist, Bode-magnitude and Bode-phase plots. An examination is made of which equivalent circuits of R(C(R(Q(RW)))) and R(C(R(Q(RW))))(CR) used for modeling the system. The effect of monomer ratio (mole fraction, X{sub TCz} = n{sub TCz}/n{sub TCz} + n{sub Py}) on the formation of copolymer is reported in 0.1 M sodium perchlorate (NaClO{sub 4})/acetonitrile (ACN) solution. The inclusion of TCz in the copolymer structure was also confirmed by FTIR-ATR, SEM, and CV measurements. The highest low frequency capacitance (C{sub LF} = 22.7 for R(C(R(Q(RW)))) and C{sub LF} = 22.6 mF cm{sup -2} for R(C(R(Q(RW))))(CR)) were obtained for X{sub TCz} = 0.91.

  17. Polymerization of Pyrrole and Thiophene on Polyethylene Adipate Electrodes

    OpenAIRE

    Erturan, Seyfettin; TORAMAN, Burcu YALVAÇ and Sena

    1998-01-01

    Polymerizations of pyrrole and thiophene on a platinum foil coated by polyethylene adipate (PEA) were carried out in acetonitrile by electrochemical methods. Different compositions of semi-conducting composite films of PEA/Polypyrrole(PPy), PEA/Polythiophene(PT) were prepared by the electrochemical polymerization of pyrrole and thiophene on PEA electrode. The polymerization was possible only for a certain thickness of the polyethylene adipate(PEA) on the platinum. Conductivities of PEA/PPy, P...

  18. An Electrochemical Investigation into a Series of Tricyanovinylated Pyrrole Moieties

    NARCIS (Netherlands)

    McCormac, Timothy; Farrell, David; Browne, Wesley; Vos, Johannes G.

    2004-01-01

    The electrochemical behavior of three tri-cyanovinylated pyrrole species namely, 2-tricyanovinyl-pyrrole (C4H4N-C5N3), 2-tricyanovinyl-N-methylpyrrole (C5H6N-C5N3) and 2-tricyanovinyl-N-phenylpyrrole (C10H8N-C5N3), has been studied. All compounds were found to exhibit both an irreversible oxidation

  19. Simple two-step synthesis of 2,4-disubstituted pyrroles and 3,5-disubstituted pyrrole-2-carbonitriles from enones

    Directory of Open Access Journals (Sweden)

    Murat Kucukdisli

    2014-02-01

    Full Text Available The cyclocondensation of enones with aminoacetonitrile furnishes 3,4-dihydro-2H-pyrrole-2-carbonitriles which can be readily converted to 2,4-disubstituted pyrroles by microwave-induced dehydrocyanation. Alternatively, oxidation of the intermediates produces 3,5-disubstituted pyrrole-2-carbonitriles.

  20. Interaction of derived polymers from pyrrole with biocompatible solutions

    International Nuclear Information System (INIS)

    This work presents a study about the synthesis by plasma, the electric properties and superficial interaction of polymers derived from pyrrole doped with Iodine with potential use as bio material. Poly-pyrrole is a semiconductor and biocompatible polymer with potential application in the development of artificial muscles and implants where the electric interaction between cells and material is an important variable. The syntheses were made at 13.5 MHz in a glass tubular reactor of 1500 cm3 with electrodes of 6.5 cm diameter and stainless steel flanges. An electrode was connected to the RF terminal of the power supply that is combined with a matching coupling resistance. The monomer and dopant used in this work were pyrrole and Iodine respectively, in closed containers. They were vaporized and injected separately into the reactor at room temperature and 0.1 mbar. The vapors of the reagents mixed freely in the reactor. The synthesis time was 240 min at 40, 60, 80 and 100 W. The polymers were obtained as thin films adhered to the reactor walls. The films were washed and swollen with distilled water and removed from the reactor walls with a small spatula. The polymers were irradiated with gamma rays at 18 and 22 KGy. Due to the fact that the doses are cumulative, the final dose applied was 40 KGy. The polymers characterization was carried out by Fourier Transform Infrared Spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy, contact angle, electrical conductivity and X-ray diffraction. The analyses indicates that the polymers have very similar structure in almost the entire power range, showing C-O, C=C, C-H, O-H, N-H bonds with a predominantly amorphous structure. The TGA analyses showed that the material has 4 or 5 loses of material. The first one starts after that 115 C except for the material irradiated at 40 KGy, this one begins in 87 C, the second one is in the interval of 196 and 295 C, the third one between 311 and 500 C, and the last

  1. Synthesis, autoxidation and photooxidation of hindered pyrrole derivatives. Hindered pyrrolic nitroxide radicals; Synthese, autoxydation et photoxidation de pyrroles encombres radicaux nitroxydes pyrroliques encombres

    Energy Technology Data Exchange (ETDEWEB)

    Ramasseul, R. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    2,5-di-t-butyl and 2,3,5-tri-t-butyl pyrrole are prepared from pinacoline and their structure is confirmed by comparison with 2,5-di-t-butyl furan and thiophene (I.R., U.V. and N.M.R. {sup 13}C satellites observation giving J{sub 13{sub C-H}} and J{sub H{sub 3}-H{sub 4}}). The sensitized photooxidation of these hindered pyrroles gives corresponding hydroperoxides which most likely structure is determined using physical and chemical methods. Oxidation of 2,5-di-t-butyl and 2,3,5-tri-t-butyl pyrrole by hydrogen peroxide in presence of inorganic per-acid of by p-nitro-perbenzoic acid does not give the pyrrolic nitroxides in contrast with secondary amines. Some N-hydroxypyrroles are then prepared from pinacoline and ethyl pivaloyl-acetate. Their oxidation by lead dioxide gives the corresponding pyrrolic nitroxides. 2,5-di-t-butyl 3,4-di-ethoxycarbonyl pyrryl 1-oxy is isolated and studied spectroscopically (visible and U.V., E.P.R.). In marked contrast with ordinary nitroxides it does not show solvent effect. It can be compared with 2,4-di-t-butyl cyclopentadienone, a carbon analog. For both, the long wave length transition does not show the usual n - {pi}* behaviour; that is confirmed by E.P.R. Using Huckel method for pyrrolic nitroxide skeleton, it is possible to have a good interpretation of experimental data. (author) [French] Les di-t-butyl 2,5 et tri-t-butyl-2,3,5 pyrrole sont synthetises a partir de la pinacoline et leur structure confirmee par comparaison avec les di-t-butyl-2,5 furanne et thiophene (I.R., U.V. et R.M.N.: observation des satellites {sup 13}C conduisant a la mesure des J{sub 13{sub C-H}} et J{sub H{sub 3}{sub -H{sub 4}}). La photoxydation sensibilisee de ces pyrroles encombres conduit aux hydroperoxydes correspondants dont la structure la plus probable est determinee par les methodes physicochimiques. L'oxydation des di-t-butyl-2,5 et tri-t-butyl-2,3,5 pyrrole par l'eau oxygenee en presence de peracide mineral ou par l'acide p

  2. Reactions of a Ruthenium Complex with Substituted N-Propargyl Pyrroles.

    Science.gov (United States)

    Chia, Pi-Yeh; Huang, Shou-Ling; Liu, Yi-Hong; Lin, Ying-Chih

    2016-04-01

    In an investigation into the chemical reactions of N-propargyl pyrroles 1 a-c, containing aldehyde, keto, and ester groups on the pyrrole ring, with [Ru]-Cl ([Ru]=Cp(PPh3 )2 Ru; Cp=C5 H5 ), an aldehyde group in the pyrrole ring is found to play a crucial role in stimulating the cyclization reaction. The reaction of 1 a, containing an aldehyde group, with [Ru]-Cl in the presence of NH4 PF6 yields the vinylidene complex 2 a, which further reacts with allyl amine to give the carbene complex 6 a with a pyrrolizine group. However, if 1 a is first reacted with allyl amine to yield the iminenyne 8 a, then the reaction of 8 a with [Ru]-Cl in the presence of NH4 PF6 yields the ruthenium complex 9 a, containing a cationic pyrrolopyrazinium group, which has been fully characterized by XRD analysis. These results can be adequately explained by coordination of the triple bond of the propargyl group to the ruthenium metal center first, followed by two processes, that is, formation of a vinylidene intermediate or direct nucleophilic attack. Additionally, the deprotonation of 2 a by R4 NOH yields the neutral acetylide complex 3 a. In the presence of NH4 PF6 , the attempted alkylation of 3 a resulted in the formation the Fischer-type amino-carbene complex 5 a as a result of the presence of NH3 , which served as a nucleophile. With KPF6 , the alkylation of 3 a with ethyl and benzyl bromoacetates afforded the disubstituted vinylidene complexes 10 a and 11 a, containing ester groups, which underwent deprotonation reactions to give the furyl complexes 12 a and 13 a, respectively. For 13 a, containing an O-benzyl group, subsequent 1,3-migration of the benzyl group was observed to yield product 14 a with a lactone unit. Similar reactivity was not observed for the corresponding N-propargyl pyrroles 1 b and 1 c, which contained keto and ester groups, respectively, on the pyrrole ring. PMID:26865008

  3. Electrogenerated poly(pyrrole-lactosyl) and poly(pyrrole-3'-sialyllactosyl) interfaces: towards the impedimetric detection of lectins

    Science.gov (United States)

    Gondran, Chantal; Dubois, Marie-Pierre; Fort, Sebastien; Cosnier, Serge

    2013-07-01

    This paper reports on the impedimetric transduction of binding reaction between polymerized saccharides and target lectins. The controlled potential electro-oxidation of pyrrole-lactosyl and pyrrole-3’-sialyllactosyl at 0.95 V vs Ag/AgCl, provides thin and reproducible poly(pyrrole-saccharide) films. The affinity binding of two lectins: Arachis hypogaea, (PNA) and Maackia amurensis (MAA) onto poly(pyrrole-lactosyl) and poly(pyrrole-3’-sialyllactosyl) electrodes, was demonstrated by cyclic voltammetry in presence of ruthenium hexamine and hydroquinone. In addition, rotating disk experiments were carried out to determine the permeability of both polypyrrole films and its evolution after incubating with lectin target. Finally, the possibility of using the poly(pyrrole-lactosyl) or poly(pyrrole-3’-siallyllactosyl) films for the impedimetric transduction of the lectin binding reaction, was investigated with hydroquinone (2×10-3 mol L-1) as a redox probe in phosphate buffer. The resuting impedance spectra were interpreted and modeled as an equivalent circuit indicating that charge transfer resistance (Rct) and relaxation frequency (f°) parameters are sensitive to the lectin binding. Rct increases from 77 to 97 Ω cm2 for PNA binding and from 93 to 131 Ω cm2 for MAA binding. In parallel, f° decreases from 276 to 222 Hz for PNA binding and from 223 to 131 Hz for MAA binding. This evolution of both parameters reflects the steric hindrances generated by the immobilised lectins towards the permeation of the redox probe.

  4. Electrogenerated poly(pyrrole-lactosyl and poly(pyrrole-3’-sialyllactosyl interfaces: towards the impedimetric detection of lectins

    Directory of Open Access Journals (Sweden)

    Chantal eGondran

    2013-07-01

    Full Text Available This paper reports on the impedimetric transduction of binding reaction between polymerized saccharides and target lectins. The controlled potential electro-oxidation of pyrrole-lactosyl and pyrrole-3’-sialyllactosyl at 0.95 V vs Ag/AgCl, provides thin and reproducible poly(pyrrole-saccharide films. The affinity binding of two lectins: Arachis hypogaea, (PNA and Maackia amurensis (MAA onto poly(pyrrole-lactosyl and poly(pyrrole-3’-sialyllactosyl electrodes, was demonstrated by cyclic voltammetry in presence of ruthenium hexamine and hydroquinone. In addition, rotating disk experiments were carried out to determine the permeability of both polypyrrole films and its evolution after incubating with lectin target. Finally, the possibility of using the poly(pyrrole-lactosyl or poly(pyrrole-3’-siallyllactosyl films for the impedimetric transduction of the lectin binding reaction, was investigated with hydroquinone (2×10-3 mol L-1 as a redox probe in phosphate buffer. The resuting impedance spectra were interpreted and modeled as an equivalent circuit indicating that charge transfer resistance (Rct and relaxation frequency (f° parameters are sensitive to the lectin binding. Rct increases from 77 to 97 Ω cm2 for PNA binding and from 93 to 131 Ω cm2 for MAA binding. In parallel, f° decreases from 276 to 222 Hz for PNA binding and from 223 to 131 Hz for MAA binding. This evolution of both parameters reflects the steric hindrances generated by the immobilised lectins towards the permeation of the redox probe.

  5. Zinc hexacyanoferrate film as an effective protecting layer in two-step and one-step electropolymerization of pyrrole on zinc substrate

    International Nuclear Information System (INIS)

    The two-step and one-step electrosynthesis processes of polypyrrole (PPy) films on the zinc substrate are described. The two-step process includes (i) the zinc surface pretreatment with hexacyanoferrate ion in the aqueous medium in order to form a zinc hexacyanoferrate (ZnHCF) film non-blocking passive layer on the surface and with the view to prevent its reactivity and (ii) electropolymerization of pyrrole on the ZnHCF vertical bar Zn-modified electrode in aqueous pyrrole solution. In this context, both the non-electrolytic and electrolytic procedures were adapted, and the effect of some experimental conditions such as supporting electrolyte, pH and temperature of the solution at the zinc surface pretreatment step as well as pyrrole concentration and electrochemical techniques at the polymerization step was investigated. By optimizing the experimental conditions in both steps, we have obtained a homogeneous and strongly adherent PPy films on the zinc substrate. The one-step process is based on the use of an aqueous medium containing Fe(CN)64- and pyrrole. The ferrocyanide ion passivates the substrate by formation of ZnHCF film during the electropolymerization process of pyrrole and therefore makes it possible to obtain strongly adherent PPy films, with controlled thickness, either by cyclic voltammetry or by electrolysis at constant current or constant potential without any previously treatment of the zinc electrode surface. The polypyrrole films deposited on the zinc electrode were characterized by cyclic voltammetry and scanning electron microscopic (SEM) measurement

  6. Hydrazonoyl Chlorides as Precursors for Synthesis of Novel Bis-Pyrrole Derivatives

    OpenAIRE

    Nabila Abdelshafy Kheder

    2016-01-01

    A convenient synthesis of some novel bis-pyrrole derivatives via hydrazonoyl halides is described. Antimicrobial evaluation of some selected examples of the synthesized products was carried out. The bis-pyrrole derivative having chloro substituents showed good activity against all of the used microbes. The molecular docking of the bis-pyrrole derivatives was performed by the Molecular Operating Environment (MOE) program.

  7. The first direct synthesis of β-unsubstituted meso-decamethylcalix[5]pyrrole

    OpenAIRE

    Chacón-García, Luis; Chávez, Lizbeth; Cacho, Denisse R; Altamirano-Hernández, Josue

    2009-01-01

    The first direct synthesis of β-unsubstituted meso-decamethylcalix[5]pyrrole from pyrrole and acetone, with moderate yield, is described. The results showed that a bismuth salt was necessary to obtain calix[5]pyrrole, with the best results obtained using Bi(NO3)3.

  8. The first direct synthesis of β-unsubstituted meso-decamethylcalix[5]pyrrole

    OpenAIRE

    Luis Chacón-García; Lizbeth Chávez; Cacho, Denisse R; Josue Altamirano-Hernández

    2009-01-01

    The first direct synthesis of β-unsubstituted meso-decamethylcalix[5]pyrrole from pyrrole and acetone, with moderate yield, is described. The results showed that a bismuth salt was necessary to obtain calix[5]pyrrole, with the best results obtained using Bi(NO3)3.

  9. Biofabrication Using Pyrrole Electropolymerization for the Immobilization of Glucose Oxidase and Lactate Oxidase on Implanted Microfabricated Biotransducers

    OpenAIRE

    Christian N. Kotanen; Olukayode Karunwi; Anthony Guiseppi-Elie

    2014-01-01

    The dual responsive Electrochemical Cell-on-a-Chip Microdisc Electrode Array (ECC MDEA 5037) is a recently developed electrochemical transducer for use in a wireless, implantable biosensor system for the continuous measurement of interstitial glucose and lactate. Fabrication of the biorecognition membrane via pyrrole electropolymerization and both in vitro and in vivo characterization of the resulting biotransducer is described. The influence of EDC-NHS covalent conjugation of glucose oxidas...

  10. A colorimetric tetrathiafulvalene-calix 4 pyrrole anion sensor

    DEFF Research Database (Denmark)

    Nielsen, K. A.

    2012-01-01

    The interaction and colorimetric sensing properties of a tetrathiafulvalene substituted calix[4]pyrrole sensor with anions were investigated using H-1 NMR and absorption spectroscopic techniques. Visual color changes were observed upon addition of different anions (Cl-, Br-, CN-, and AcO-) to a s......The interaction and colorimetric sensing properties of a tetrathiafulvalene substituted calix[4]pyrrole sensor with anions were investigated using H-1 NMR and absorption spectroscopic techniques. Visual color changes were observed upon addition of different anions (Cl-, Br-, CN-, and Ac......O-) to a solution of the sensor. (C) 2012 Elsevier Ltd. All rights reserved....

  11. Bandgap Engineering in π-Extended Pyrroles. A Modular Approach to Electron-Deficient Chromophores with Multi-Redox Activity.

    Science.gov (United States)

    Zhylitskaya, Halina; Cybińska, Joanna; Chmielewski, Piotr; Lis, Tadeusz; Stępień, Marcin

    2016-09-01

    A family of bandgap-tunable pyrroles structurally related to rylene dyes was computationally designed and prepared using robust, easily scalable chemistry. These pyrroles show highly variable fluorescence properties and can be used as building blocks for the synthesis of electron-deficient oligopyrroles. The latter application is demonstrated through the development of π-extended porphyrins containing naphthalenediamide or naphthalenediimide units. These new macrocycles exhibit simultaneously tunable visible and near-IR absorptions, an ability to accept up to 8 electrons via electrochemical reduction, and high internal molecular free volumes. When chemically reduced under inert conditions, the most electron-deficient of these macrocycles revealed reversible formation of eight charged states, characterized by remarkably red-shifted optical absorptions, extending beyond 2200 nm. Such features make these oligopyrroles of interest as functional chromophores, charge-storage materials, and tectons for crystal engineering. PMID:27533895

  12. Both visual and fluorescent sensors for Zn2 + based on bis(pyrrol-2-yl-methyleneamine) platform

    Science.gov (United States)

    Wu, Wei-Na; Mao, Pan-Dong; Jia, Lei; Wang, Yuan; Xu, Zhou-Qing

    2016-09-01

    Two bis(pyrrol-2-yl-methyleneamine) chemo-sensors, 1, 3- and 1, 4-bis[3,4-dimethyl-5-ethyloxy -carbonyl-pyrrol-2-yl-methyleneamine]benzene (H2L1 and H2L2, respectively) have been synthesized and characterized, which exhibit high selectivity as off-on fluorescence sensors toward Zn2 + in CH3CN/H2O (9:1, v/v) solution. The detection limits of both sensors are at the parts per million level. Moreover, the probes H2L1 and H2L2 could sense Zn2 + by "naked eye" with a color change from colorless to yellow, and from yellow to dark yellow, respectively. To test the practical use of the probes, the determination of Zn2 + in real water samples was also evaluated.

  13. Poly(1-(2-carboxyethyl)pyrrole)/polypyrrole composite nanowires for glucose biosensor

    International Nuclear Information System (INIS)

    A novel glucose biosensor based on poly(1-(2-carboxyethyl)pyrrole) (PPyCOOH)/polypyrrole (PPy) composite nanowires was developed by immobilizing glucose oxidase (GOD) on the nanowires via covalent linkages. The PPyCOOH/PPy composite nanowires were fabricated by a facile two-step electrochemical synthesis route. First, PPy nanowires were synthesized in phosphate buffer solution using organic sulfonic acid, p-toluenesulfonate acid, as soft-template. Then, PPyCOOH/PPy composite nanowires were obtained by polymerizing 1-(2-carboxyethyl)pyrrole onto PPy nanowires via electrochemical method. Scanning electron microscopic, FT-IR spectra, X-ray photoelectron spectroscopy and cyclic voltammograms were used to characterize the structural and electrical behaviors of the composite nanowires. The PPyCOOH/PPy composite nanowires exhibited uniform diameter, high reactive site (-COOH), large specific surface, excellent electroactivity and good adhesion to electrode. The glucose biosensor was constructed by covalently coupling GOD to the composite nanowires. The biosensor response was rapid (5 s), highly sensitive (33.6 μA mM−1 cm−2) with a wide linear range (up to 10.0 mM) and low detection limit (0.63 μM); it also exhibited high stability and specificity to glucose. The attractive electrochemical and structural properties of PPyCOOH/PPy composite nanowires suggested potential application for electrocatalysis and biosensor.

  14. Calix[4]pyrrole-based ion pair receptors.

    Science.gov (United States)

    Kim, Sung Kuk; Sessler, Jonathan L

    2014-08-19

    Ion pair receptors, which are able to bind concurrently both a cation and an anion, often display higher selectivity and affinity for specific ion pairs than simple ion receptors capable of recognizing primarily either a cation or an anion. This enhancement in recognition function is attributable to direct or indirect cooperative interactions between cobound ions via electrostatic attractions between oppositely charged ions, as well as to positive allosteric effects. In addition, by virtue of binding the counterions of the targeted ion, ion pair receptors can minimize the solvation of the counterions, which can otherwise have a negative effect on the interactions between the receptors and the targeted ions. As a result of their more favorable interactions, ion pair receptors are attractive for use in applications, such as extraction and sensing, where control of the binding interactions is advantageous. In this Account, we illustrate this potential in the context of ion pair receptors based on the calix[4]pyrrole scaffold. Both simple ditopic ion pair receptors, containing sites for the recognition of a single anion and single cation, and so-called multitopic ion pair receptors will be discussed. The latter systems differ from conventional, so-called ditopic ion pair receptors in that they contain more than one binding site for a given targeted ion (e.g., a cation). This permits a level of selectivity and control over binding function not normally seen for simple ion or ion pair receptors containing one or two binding sites, respectively. Calix[4]pyrroles are macrocyclic compounds consisting of four pyrrole units linked via fully substituted sp(3) hybridized meso carbon atoms. They are effective receptors for Lewis basic anions (e.g., halides) in typical organic media and under certain conditions will recognize ion pairs containing charge diffuse cations, such as a small alkylammonium, imidazolium, or cesium cations. The calix[4]pyrrole framework is further

  15. Synthetic, structural and biological studies of organosilicon(IV complexes of Schiff bases derived from pyrrole-2-carboxaldehyde

    Directory of Open Access Journals (Sweden)

    KIRAN SING

    2010-07-01

    Full Text Available Selected new organosilicon(IV complexes having the general formula R2SiCl[L] and R2Si[L] 2 were synthesized by the reactions of Me2SiCl2 with Schiff bases (5-mercapto-4-[(1H-pyrrol-2ylmethyleneamino]-s-triazole, 5-mercapto-3-methyl-4-[(1H-pyrrol-2ylmethyleneamino]-s-triazole and 3-ethyl-5-mercapto-4-[(1H-pyrrol-2ylmethyleneamino]-s-triazole in 1:1 and 1:2 molar ratios. All of the compounds were characterized by elemental analysis, molar conductance, and IR, UV, 1H-, 13C- and 29Si-NMR spectral studies. All the spectral data suggest an involvement with an azomethine nitrogen in coordination to the central silicon atom. With the help of above-mentioned spectral studies, penta and hexacoordinated environments around the central silicon atoms in the 1:1 and 1:2 complexes, respectively, are proposed. Finally, the free ligands and their metal complexes were tested in vitro against some pathogenic bacteria and fungi to assess their antimicrobial properties.

  16. Calix[4]pyrrole derivative: recognition of fluoride and mercury ions and extracting properties of the receptor-based new material.

    Science.gov (United States)

    de Namor, Angela F Danil; Khalife, Rasha

    2008-12-11

    A calix[4]pyrrole derivative, namely, meso-tetramethyl tetrakis (4-phenoxy methyl ketone) calix[4]pyrrole, 1, was synthesized and structurally (1H NMR) and thermodynamically characterized. The complexing properties of this receptor with a wide variety of anions and cations in dipolar aprotic media (acetonitrile, propylene carbonate, and dimethyl sulfoxide) were investigated through 1H NMR and conductance studies. The former technique was used to assess whether or not complexation occurs and if so to identify the active sites of interaction of 1 with ions. The composition of the complexes was established by conductance measurements. It was found that in dipolar aprotic solvents, 1 interacts only with two polluting ions (fluoride and mercury). The complexation thermodynamics of 1 and these ions in these solvents is reported. The medium effect on the binding process involving the fluoride ion is discussed taking into account the solvation properties of reactants and the product. Complexes of moderate stability are found. Given that this is an important factor to consider for the recycling of the loaded material in extraction processes, 1 was treated with formaldehyde in basic medium leading to the production of a calix[4]pyrrole based material able to extract fluoride and mercury (II) ions from water. Thus the optimum conditions for the extraction of these ions from aqueous solutions were established. The material is easily recyclable using an organic acid. Final conclusions are given. PMID:19053691

  17. Calix[4]pyrrole derivative: recognition of fluoride and mercury ions and extracting properties of the receptor-based new material.

    Science.gov (United States)

    de Namor, Angela F Danil; Khalife, Rasha

    2008-12-11

    A calix[4]pyrrole derivative, namely, meso-tetramethyl tetrakis (4-phenoxy methyl ketone) calix[4]pyrrole, 1, was synthesized and structurally (1H NMR) and thermodynamically characterized. The complexing properties of this receptor with a wide variety of anions and cations in dipolar aprotic media (acetonitrile, propylene carbonate, and dimethyl sulfoxide) were investigated through 1H NMR and conductance studies. The former technique was used to assess whether or not complexation occurs and if so to identify the active sites of interaction of 1 with ions. The composition of the complexes was established by conductance measurements. It was found that in dipolar aprotic solvents, 1 interacts only with two polluting ions (fluoride and mercury). The complexation thermodynamics of 1 and these ions in these solvents is reported. The medium effect on the binding process involving the fluoride ion is discussed taking into account the solvation properties of reactants and the product. Complexes of moderate stability are found. Given that this is an important factor to consider for the recycling of the loaded material in extraction processes, 1 was treated with formaldehyde in basic medium leading to the production of a calix[4]pyrrole based material able to extract fluoride and mercury (II) ions from water. Thus the optimum conditions for the extraction of these ions from aqueous solutions were established. The material is easily recyclable using an organic acid. Final conclusions are given.

  18. Multiphoton ionization of pyrrole-water mixed clusters

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Multiphoton ionization of the hydrogen-bonded pyrrole-water clusters ( C4H5 N)n H2O)m is studied with a reflectron—time of flight mass spectrometer at 355 nm. With increasing partial concentration of pyrrole in a gas mixture source, a series of poly-pyrrole-water binary-mixed cluster ions can be observed, including unprotonated cluster ions [(C4H5N)x (H2O)y]* , protonated cluster ions [(C4H5N)x (H2O)yH]* and dehydrogenated cluster ions [ ( C4 H4 N) ( C4 H5 N) x ( H2O) y ] + . Ab initio calculations of their structures, bond strengths, charge distributions and re action energies are carried out. Stable structures of these clusters are obtained from the calculations. A probable forma tion mechanism of the cluster ions [(C4H5N)x(H2O)y] + , [(C4H5N)x (H2O)y]H+ and [(C4H4N) (C4H5N)x (H2O)y]-is supposed to be the ionization of clusters followed by dissociation.

  19. Numerical Analysis Of Hooke Jeeves-Runge Kutta To Determine Reaction Rate Equation In Pyrrole Polymerization

    International Nuclear Information System (INIS)

    The numerical analysis of Hooke Jeeves Methods combined with Runge Kutta Methods is used to determine the exact model of reaction rate equation of pyrrole polymerization. Chemical polymerization of pyrrole was conducted with FeCI3 / pyrrole solution at concentration ratio of 1.62 mole / mole and 2.18 mole / mole with varrying temperature of 28, 40, 50, and 60 oC. FeCl3 acts as an oxidation agent to form pyrrole cation that will polymerize. The numerical analysis was done to examine the exact model of reaction rate equation which is derived from reaction equation of initiation, propagation, and termination. From its numerical analysis, it is found that the pyrrole polymerization follows third order of pyrrole cation concentration

  20. Hydrazonoyl Chlorides as Precursors for Synthesis of Novel Bis-Pyrrole Derivatives

    Directory of Open Access Journals (Sweden)

    Nabila Abdelshafy Kheder

    2016-03-01

    Full Text Available A convenient synthesis of some novel bis-pyrrole derivatives via hydrazonoyl halides is described. Antimicrobial evaluation of some selected examples of the synthesized products was carried out. The bis-pyrrole derivative having chloro substituents showed good activity against all of the used microbes. The molecular docking of the bis-pyrrole derivatives was performed by the Molecular Operating Environment (MOE program.

  1. Poly(pyrrole-co-pyrrole propylic acid) film and its application in label-free surface plasmon resonance immunosensors.

    Science.gov (United States)

    Hu, Weihua; Li, Chang Ming; Dong, Hua

    2008-12-01

    In this work, surface plasmon resonance (SPR) was used to study protein immobilization on poly(pyrrole-co-pyrrole propylic acid) (PPy/PPa) for immunosensing applications. SPR was employed to in situ monitor the electropolymerization process and to control thickness of the PPy/PPa copolymer film. Goat IgG as a model protein was covalently immobilized on the carboxyl-containing film through EDC/NHS as the coupling reagents. The effect of pyrrole propylic acid (Pa) proportion in the deposition solution on the protein immobilization capability was systemically investigated. The immobilization efficiency was demonstrated by a label-free SPR immunosensor. The heterogeneous kinetics of the immune reaction was discussed. This work could provide a facile method to immobilize proteins on an electrode surface by electropolymerized copolymer, and renders a universal approach to in situ study the protein immobilization process and sensing kinetics for scientific insights of the heteroimmunosensing scheme particularly in surface chemistry and molecular biology for further improvement of immunosensors. PMID:19068327

  2. A novel quinoxaline bearing electroactive monomer: Pyrrole as the donor moiety

    Energy Technology Data Exchange (ETDEWEB)

    Taskin, Asli Tuba; Balan, Abidin; Epik, Bugra; Yildiz, Ersin [Middle East Technical University, Department of Chemistry, 06531, Ankara (Turkey); Udum, Yasemin Arslan [Gazi University, Institute of Science and Technology, Department of Advanced Technologies, 06570, Ankara (Turkey); Toppare, Levent [Middle East Technical University, Department of Chemistry, 06531, Ankara (Turkey)], E-mail: toppare@metu.edu.tr

    2009-09-30

    A novel electroactive monomer 5,8-di(1H-pyrrol-2-yl)-2,3-di(thiophen-2-yl)quinoxaline (PTQ) was successfully synthesized and its electrochromic properties were reported. Nuclear magnetic resonance ({sup 1}H NMR-{sup 13}C NMR) and mass spectroscopy were used to characterize the monomer. The monomer was electrochemically polymerized in the presence of tetrabutylammonium perchlorate (TBAP) as supporting electrolyte in dichloromethane. Monomer reveals relatively low oxidation potential at +0.70 V. Spectroelectrochemical behaviors and switching ability of homopolymer were investigated by UV-vis spectroscopy and cyclic voltammetry. Two {pi}-{pi}* transitions were observed at 400 and 815 nm with a low band gap, 1.0 eV. Polymer possesses 66% optical contrast in the Near IR region, which may be promising in NIR electrochromic device applications.

  3. A novel quinoxaline bearing electroactive monomer: Pyrrole as the donor moiety

    International Nuclear Information System (INIS)

    A novel electroactive monomer 5,8-di(1H-pyrrol-2-yl)-2,3-di(thiophen-2-yl)quinoxaline (PTQ) was successfully synthesized and its electrochromic properties were reported. Nuclear magnetic resonance (1H NMR-13C NMR) and mass spectroscopy were used to characterize the monomer. The monomer was electrochemically polymerized in the presence of tetrabutylammonium perchlorate (TBAP) as supporting electrolyte in dichloromethane. Monomer reveals relatively low oxidation potential at +0.70 V. Spectroelectrochemical behaviors and switching ability of homopolymer were investigated by UV-vis spectroscopy and cyclic voltammetry. Two π-π* transitions were observed at 400 and 815 nm with a low band gap, 1.0 eV. Polymer possesses 66% optical contrast in the Near IR region, which may be promising in NIR electrochromic device applications.

  4. One-pot Green Synthesis of Pyrrole Derivatives Catalyzed by Nano Sulfated Zirconia as a Solid Acid Catalyst%One-pot Green Synthesis of Pyrrole Derivatives Catalyzed by Nano Sulfated Zirconia as a Solid Acid Catalyst

    Institute of Scientific and Technical Information of China (English)

    Teimouri, Abbas; Chermahini, Alireza Najafi

    2012-01-01

    A new and efficient method for the preparation of N-substituted pyrroles from one-pot Paal-Knorr condensation has been accomplished using nano-crystalline sulfated zirconia (SZ) as the catalyst in ethanol at moderate temperature. This new protocol has the advantages of easy availability, stability, reusability and eco-friendliness of the catalyst, high to excellent yields, simple experimental and work-up procedure. The synthesized compounds were confirmed through spectral characterization using IR, 1H NMR, 13C NMR and mass spectra.

  5. Quadrupolar, emission-tunable pi-expanded 1,4-dihydropyrrolo 3,2-b pyrroles - synthesis and optical properties

    DEFF Research Database (Denmark)

    Janiga, A.; Bednarska, D.; Thorsted, B.;

    2014-01-01

    . It was demonstrated that the increase in the molecular length of the chromophore effectively extends pi-conjugation. The effect of structural variations on photophysical properties was studied in detail for these compounds and the relationship between the structure and photophysical properties was thoroughly......The synthesis and optical characterization of six novel heteroaromatic-based chromophores is described. The new dyes present mostly an A-D-A general framework, where A is an electron-deficient aromatic ring and D is an electron-rich pyrrolo[3,2-b] pyrrole moiety, linked via triple bonds...

  6. Interesting reactivity of diketones with pyrrole under acidic condition

    Indian Academy of Sciences (India)

    Sanjeev Pran Mahanta; Pradeepta Kumar Panda

    2011-09-01

    The acid catalysed condensation of diketones with pyrrole did not result in the formation of expected divergent bisdipyrromethane always; instead the product depends on the chain length of the diketones, in particular the distance between the two carbonyl functional groups.When the two carbonyl groups are linked via one or two methylene groups, unusual ring annulation occurs resulting in the formation of various bridged bipyrroles. However, on further increase in the length of the spacer, between the two carbonyl groups, synthesis of the expected bisdipyrromethanes could be achieved.

  7. A Novel TetraTTF-calix[4]pyrrole Ouroborand for Explosive Detection

    DEFF Research Database (Denmark)

    Bähring, Steffen; Nielsen, Kent

    We have synthesized the first example of an asymmetric tetraTTF-calix[4]pyrrole. This system features Ouroborand qualities due to selfcomplexation with the pyridine substituent. This forces the usually highly flexible calix[4]pyrrole into a preorganized conformation with improved explosive...

  8. Novel and efficient supramolecular synthesis of pyrroles in the presence of β-cyclodextrin in water

    Institute of Scientific and Technical Information of China (English)

    K. Ramesh; K. Karnakar; G. Satish; Y.V.D. Nageswar

    2012-01-01

    A simple and efficient synthesis of highly substituted pyrroles was achieved in water medium via multi-component strategy,using amine,DMAD/DEAD as well as phenacyl bromide catalyzed by β-CD.Utilizing this protocol various pyrrole derivatives were synthesized in good to excellent yields.

  9. A Novel TetraTTF-calix[4]pyrrole Ouroborand for Explosive Detection

    DEFF Research Database (Denmark)

    Bähring, Steffen; Nielsen, Kent

    2010-01-01

    We have synthesized the first example of an asymmetric tetraTTF-calix[4]pyrrole. This system features Ouroborand qualities due to selfcomplexation with the pyridine substituent. This forces the usually highly flexible calix[4]pyrrole into a preorganized conformation with improved explosive...

  10. Pyrrolic Amide: A New Hydrogen Bond Building Block for Self-assembly

    Institute of Scientific and Technical Information of China (English)

    YIN Zhen-Ming; LI Jian-Feng; HE Jia-Qi; ZHU Xiao-Qing; CHENG Jin-Pei

    2003-01-01

    @@ Molecular self-assembly has emerged as a powerful technology for the synthesis of nanostructured materials. In design of various molecular assemblies, hydrogen bonding is a preferably selected intra- or inter-molecular weak interaction in recent research by virtue of the directionality and specificity. The research for novel hydrogen bond building blocks that self-assembly into well defined structures is great important not only for gaining an understanding of the concepts of self-assembly but also for the design of new molecular materials. Pyrrolic amide moiety has one hydrogen bond acceptor (C =O) and two hydrogen bond donors (pyrrole NH and amide NH). By deliberately design, pyrrolic amide compounds would be new kinds hydrogen bond building blocks. So, pyrrolic amide compounds 1 ~ 6, which bear one, two or three pyrrolic amide moieties respectively, were designed and synthesized.

  11. Ferrocene-Functionalized 4-(2,5-Di(thiophen-2-yl-1H-pyrrol-1-ylaniline: A Novel Design in Conducting Polymer-Based Electrochemical Biosensors

    Directory of Open Access Journals (Sweden)

    Rukiye Ayranci

    2015-01-01

    Full Text Available Herein, we report a novel ferrocenyldithiophosphonate functional conducting polymer and its use as an immobilization matrix in amperometric biosensor applications. Initially, 4-(2,5-di(thiophen-2-yl-1H-pyrrol-1-ylamidoferrocenyldithiophosphonate was synthesized and copolymerized with 4-(2,5-di(thiophen-2-yl-1H-pyrrol-1-ylbenzenamine at graphite electrodes. The amino groups on the polymer were utilized for covalent attachment of the enzyme glucose oxidase. Besides, ferrocene on the backbone was used as a redox mediator during the electrochemical measurements. Prior to the analytical characterization, optimization studies were carried out. The changes in current signals at +0.45 V were proportional to glucose concentration from 0.5 to 5.0 mM. Finally, the resulting biosensor was applied for glucose analysis in real samples and the data were compared with the spectrophotometric Trinder method.

  12. Electrochromic properties of multicolored novel polymer synthesized via combination of benzotriazole and N-functionalized 2,5-di(2-thienyl)-1H-pyrrole units

    International Nuclear Information System (INIS)

    Synthesis of new conducting polymers is desired since their electrochemical and optical properties enable them to be used as active layers in many device applications. Benzotriazole and N-functionalized 2,5-di(2-thienyl)-1H-pyrrole (SNS Series) containing polymers showed very promising results as electrochromic materials. In order to observe the effect of the combination of these two units, three new monomers; 2-(6-(2,5-bis(5-methylthiophen-2-yl)-1H-pyrrol-1-yl)hexyl)-4,7-di (thiophen-2-yl)-2H benzo[d][1,2,3]triazole (M1), 2-(6-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)hexyl)-4,7-di(thiophen-2-yl) -2H-benzo[d][1,2,3]triazole (M2) and 2-(6-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)hexyl)-4,7-bis (5-methylthiophen-2-yl)-2H-benzo[d][1,2,3]triazole (M3) were synthesized. To better characterize the electronic and spectroscopic properties of the monomers, density functional theory (DFT) and its time-dependent generalization (TD-DFT) were used to calculate their vertical ionization potentials, vertical electron affinity and to simulate and interpret their infrared and UV-vis spectra. The monomers were electrochemically polymerized and the resultant polymers were characterized with cyclic voltammetry and UV-vis-NIR spectroscopy techniques. An electrochromic device was constructed with electrochemical polymer of M2. The device switched between red and blue colors and showed exceptional optical memory

  13. Ru-catalyzed site-selective direct arylation polycondensation via ortho-metalation of pyrrole derivative

    International Nuclear Information System (INIS)

    A Ti-conjugated polymer consisting of pyrrole and fluorene units was synthesized via Ru-catalyzed direct arylation polycondensation. The introduction of a 2-pyrimidinyl substituent into the N -position of the pyrrole monomer as a directing group induced ortho-metalation, with effective site-selective polycondensation at the α-position of the pyrrole monomer, without the need for protection of the β-position. Subsequent removal of the 2-pyrimidinyl substituent led to the elongation of π-conjugation along the main chain of the polymer via elimination of the steric hindrance due to the bulky substituent

  14. 2-Ethyl 4-methyl 5-ethyl-3-methyl-1H-pyrrole-2,4-dicarboxylate

    Directory of Open Access Journals (Sweden)

    Gui-Fen Lu

    2012-02-01

    Full Text Available The title pyrrole derivative compound, C12H17NO4, was synthesized from methyl 3-oxopentanoate by a Knorr-type reaction and contains a pyrrole ring to which two diagonal alkoxycarbonyl groups and two diagonal alkyl substituents are attached. The methylcarbonyl and ethylcarbonyl substituents are approximately co-planar with the pyrrole ring, making dihedral angles of 5.64 (2 and 3.44 (1°, respectively. In the crystal, adjacent molecules are assembled by pairs of N—H...O hydrogen bonds into dimers in a head-to-head mode.

  15. A Submarine Journey: The Pyrrole-Imidazole Alkaloids

    Directory of Open Access Journals (Sweden)

    Alessandra Scolaro

    2009-11-01

    Full Text Available In his most celebrated tale “The Picture of Dorian Gray”, Oscar Wilde stated that “those who go beneath the surface do so at their peril”. This sentence could be a prophetical warning for the practitioner who voluntarily challenges himself with trying to synthesize marine sponge-deriving pyrrole-imidazole alkaloids. This now nearly triple-digit membered community has been growing exponentially in the last 20 years, both in terms of new representatives and topological complexity − from simple, achiral oroidin to the breathtaking 12-ring stylissadines A and B, each possessing 16 stereocenters. While the biosynthesis and the role in the sponge economy of most of these alkaloids still lies in the realm of speculations, significant biological activities for some of them have clearly emerged. This review will account for the progress in achieving the total synthesis of the more biologically enticing members of this class of natural products.

  16. A submarine journey: the pyrrole-imidazole alkaloids.

    Science.gov (United States)

    Forte, Barbara; Malgesini, Beatrice; Piutti, Claudia; Quartieri, Francesca; Scolaro, Alessandra; Papeo, Gianluca

    2009-11-27

    In his most celebrated tale "The Picture of Dorian Gray", Oscar Wilde stated that "those who go beneath the surface do so at their peril". This sentence could be a prophetical warning for the practitioner who voluntarily challenges himself with trying to synthesize marine sponge-deriving pyrrole-imidazole alkaloids. This now nearly triple-digit membered community has been growing exponentially in the last 20 years, both in terms of new representatives and topological complexity--from simple, achiral oroidin to the breathtaking 12-ring stylissadines A and B, each possessing 16 stereocenters. While the biosynthesis and the role in the sponge economy of most of these alkaloids still lies in the realm of speculations, significant biological activities for some of them have clearly emerged. This review will account for the progress in achieving the total synthesis of the more biologically enticing members of this class of natural products.

  17. A Submarine Journey: The Pyrrole-Imidazole Alkaloids †

    Science.gov (United States)

    Forte, Barbara; Malgesini, Beatrice; Piutti, Claudia; Quartieri, Francesca; Scolaro, Alessandra; Papeo, Gianluca

    2009-01-01

    In his most celebrated tale “The Picture of Dorian Gray”, Oscar Wilde stated that “those who go beneath the surface do so at their peril”. This sentence could be a prophetical warning for the practitioner who voluntarily challenges himself with trying to synthesize marine sponge-deriving pyrrole-imidazole alkaloids. This now nearly triple-digit membered community has been growing exponentially in the last 20 years, both in terms of new representatives and topological complexity – from simple, achiral oroidin to the breathtaking 12-ring stylissadines A and B, each possessing 16 stereocenters. While the biosynthesis and the role in the sponge economy of most of these alkaloids still lies in the realm of speculations, significant biological activities for some of them have clearly emerged. This review will account for the progress in achieving the total synthesis of the more biologically enticing members of this class of natural products. PMID:20098608

  18. Auto-oligomerization and hydration of pyrrole revealed by x-ray absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Advanced Light Source; Schwartz, Craig P.; Uejio, Janel S.; Duffin, Andrew M.; England, Alice H.; Prendergast, David; Saykally, Richard J

    2009-05-29

    Near edge x-ray absorption fine structure (NEXAFS) spectra have been measured at the carbon and nitrogen K-edges of the prototypical aromatic molecule, pyrrole, both in the gas phase and when solvated in water, and compared with spectra simulated using a combination of classical molecular dynamics and first principles density functional theory in the excited state core hole approximation. The excellent agreement enabled detailed assignments. Pyrrole is highly reactive, particularly in water, and reaction products formed by the auto-oligomerization of pyrrole are identified. The solvated spectra have been measured at two different temperatures, indicating that the final states remain largely unaffected by both hydration and temperature. This is somewhat unexpected, since the nitrogen in pyrrole can donate a hydrogen bond to water.

  19. Synthesis and biological activity of pyrrole analogues of combretastatin A-4.

    Science.gov (United States)

    Jung, Eun-Kyung; Leung, Euphemia; Barker, David

    2016-07-01

    A series of pyrrole analogues of combretastatin (CA-4) were synthesized and tested for their anti-proliferative activity. The highly diastereoselective acyl-Claisen rearrangement was used to provide 2,3-syn disubstituted morpholine amides which were used as precursors for the various analogues. This synthesis allows for the preparation of 1,2- and 2,3-diaryl-1H-pyrroles which are both geometrically similar to CA-4. These pyrrolic analogues were tested for their anti-proliferative activity against two human cell lines, K562 and MDA-MB-231 with 2,3-diaryl-1H-pyrrole 35 exhibiting the most potent activity with IC50 value of 0.07μM against MDA-MB-231 cell line.

  20. One-Pot Conversion of Carbohydrates into Pyrrole-2-carbaldehydes as Sustainable Platform Chemicals.

    Science.gov (United States)

    Adhikary, Nirmal Das; Kwon, Sunjeong; Chung, Wook-Jin; Koo, Sangho

    2015-08-01

    A practical conversion method of carbohydrates into N-substituted 5-(hydroxymethyl)pyrrole-2-carbaldehydes (pyrralines) was developed by the reaction with primary amines and oxalic acid in DMSO at 90 °C. Further cyclization of the highly functionalized pyrralines afforded the pyrrole-fused poly-heterocyclic compounds as potential intermediates for drugs, food flavors, and functional materials. The mild Maillard variant of carbohydrates and amino esters in heated DMSO with oxalic acid expeditiously produced the pyrrole-2-carbaldehyde skeleton, which can be concisely transformed into the pyrrole alkaloid natural products, 2-benzyl- and 2-methylpyrrolo[1,4]oxazin-3-ones 8 and 9, lobechine 10, and (-)-hanishin 11 in 23-32% overall yields from each carbohydrate.

  1. A mixed experimental and DFT study on ethyl 4-[3-(4-dimethylamino-phenyl)-acryloyl]-3,5-dimethyl-1H-pyrrole-2-carboxylate

    Science.gov (United States)

    Singh, R. N.; Rawat, Poonam; Sahu, Sangeeta

    2014-05-01

    A new pyrrole containing chalcone, ethyl 4-[3-(4-dimethylamino-phenyl)-acryloyl]-3,5-dimethyl-1H-pyrrole-2-carboxylate (EDPADPC) derived from ethyl 4-acetyl-3,5-dimethyl-1H-pyrrole-2-carboxylate and 4-dimethylamino-benzaldehyde has been characterized by spectroscopic techniques (1H NMR, UV-Visible, FT-IR) and results have been compared by means of theoretical findings. A combined experimental and theoretical vibrational analysis identified red shifts in vNH and vCO indicating the formation of dimer in the solid state. The binding energy of dimer has been evaluated as 9.89 kcal/mol and the strength and nature of hydrogen bonding have also been analyzed in detail. The DFT derived reactivity descriptors indicate that EDPADPC is suitable for the formation of new heterocyclic compounds. The first hyperpolarizability (β0) of EDPADPC has been computed and found to be 62.0226 × 10-30 indicating its use as non-linear optical (NLO) material.

  2. Synthesis of new 2,5-dimethyl pyrrole derivatives from acetonylacetone

    Institute of Scientific and Technical Information of China (English)

    Xiao Ming Ji; Ye Lu; Ming Qin Zhao; Xiao Yun Zhang; Yun Liu; Le Liu

    2010-01-01

    Acetonylacetone 1 was treated with thiourea, aniline, glycine and glutamic acid to give pyrrole derivatives 2, 3, 5, and 9 by Paal-Knorr reaction, respectively. Then 3 was successfully transformed into the related pyrrole derivative 4 by Mannich reaction.Compounds 6, 7 and 8 were obtained by reacting 5 with phenethyl alcohol, phenylallylic alcohol and leaf alcohol by esterification reactions, respectively. The structures of all new products were elucidated by IR, NMR and HRMS spectra.

  3. Energetics of 1-(aminophenyl)pyrroles: A joint calorimetric and computational study

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Ana Filipa L.O.M. [Centro de Investigacao em Quimica, Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal); Ribeiro da Silva, Manuel A.V., E-mail: risilva@fc.up.pt [Centro de Investigacao em Quimica, Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal)

    2011-10-15

    Highlights: > Enthalpy of formation of crystalline 1-(2-aminophenyl)pyrrole was determined by combustion calorimetry. > Vapor pressures of 1-(aminophenyl)pyrrole were measured as function of temperature by the Knudsen effusion technique. > Enthalpies of formation of the three gaseous isomers of 1-(aminophenyl)pyrrole were obtained by G3(MP2)//B3LYP calculations. - Abstract: Static bomb calorimetry and the Knudsen effusion mass-loss technique were used to derive, respectively, the standard (p{sup o} = 0.1 MPa) molar enthalpy of formation, in the crystalline phase, {Delta}{sub f}H{sub m}{sup 0}(cr), and the standard molar enthalpy of sublimation, at T = 298.15 K, {Delta}{sub cr}{sup g}H{sub m}{sup 0}, of 1-(2-aminophenyl)pyrrole. These experiments allowed the determination of its standard (p{sup o} = 0.1 MPa) molar enthalpy of formation, in the gaseous phase, {Delta}{sub f}H{sub m}{sup 0}(g), at T = 298.15 K, as (224.1 {+-} 2.4) kJ . mol{sup -1}. The gas-phase enthalpy of formation of 1-(2-aminophenyl)pyrrole was also estimated by G3(MP2)//B3LYP calculations, which were further extended to the (aminophenyl)pyrroles that were not studied experimentally. Experimental and theoretical results are in very good agreement.

  4. Synthesis of π-conjugated systems bearing thiophene and pyrrole heterocycles through palladium-catalyzed decarboxylative cross-coupling reaction

    OpenAIRE

    Castro, M. Cidália R.; Fonseca, A. Maurício C.; Raposo, M. Manuela M.

    2012-01-01

    Thiophene and pyrrole moieties play important roles in synthetic and medicinal chemistry, as they are present in a large number of natural products and biologically active compounds. For this reason, amongst all five-membered aromatic heterocycles, molecules containing the pyrrole nucleus have attracted the greatest attention of researchers and have been studied in most detail. Especially, 2-aryl- and 2-heteroaryl-substituted pyrroles are of great interest to the pharmaceutical industry, for ...

  5. Highly Sensitive Bisphenol-A Electrochemical Aptasensor Based on Poly(Pyrrole-Nitrilotriacetic Acid)-Aptamer Film.

    Science.gov (United States)

    Kazane, Imen; Gorgy, Karine; Gondran, Chantal; Spinelli, Nicolas; Zazoua, Ali; Defrancq, E; Cosnier, Serge

    2016-07-19

    An electrochemical highly sensitive aptasensor was developed based on electropolymerized poly(pyrrole-nitrilotriacetic) acid film and a new aptamer functionalized by a pentahistidine peptide for the quantification of bisphenol A. A surface coverage of antibisphenol A aptamer of 1.84 × 10(-10) mol cm(-2) was estimated from the electrochemical signal of the [Ru(III)(NH3)6](3+) complex bound by electrostatic interactions onto the aptamer-modified electrode. The binding of bisphenol A onto the polymer film was successfully characterized by electrochemical methods as square wave voltammetry and electrochemical impedance spectroscopy measurements. The designed label-free impedimetric aptasensor displayed a wide linear range from 10(-11) to 10(-6) mol L(-1) with a sensitivity of 372 Ω per unit of log of concentration and an excellent specificity toward interfering agents such as 4,4'-dihydroxybiphenyl and bisphenol P. PMID:27332710

  6. Ultrasound promoted N-alkylation of pyrrole using potassium superoxide as base in crown ether.

    Science.gov (United States)

    Yim, E S; Park, M K; Han, B H

    1997-04-01

    Ultrasound accelerates the N-alkylation of pyrrole by alkylating reagents using potassium superoxide as base in the presence of 18-crown-6. A much lower yield of N-alkylated pyrrole was realized in the absence of ultrasound. N-alkylating reagents employed for pyrrole are methyl iodide, ethyl bromide, benzyl bromide, as well as acrylonitrile allyl cyanide and methyl acrylate. In an extension of this work, we have found that ultrasound was not necessary for the N-alkylation of indole and alkyl amine, such as diphenyl amine and piperidine with alkyl halides using our reagents. In all cases we observed that the 18-crown-6 catalyzed N-alkylation reaction gives higher yields of N-alkylated products than that without crown ether, when potassium superoxide was used as base. These observations are probably due to the potassium-crown complex which can be released when the reaction goes to completion. PMID:11237050

  7. A novel and facile approach for synthesis of 5-amino-7-aryl-6-cyano-4-pyrano[3,2-]pyrroles

    Indian Academy of Sciences (India)

    Reza Sandaroos; Saman Damavandi

    2012-07-01

    An efficient and iron-catalysed synthesis of 4-pyrano[3,2-]pyrrole is reported. The reactions proceed through a one-pot, three component cyclocondensation of 3-hydroxypyrrole, malononitrile and various aldehydes to afford 4-pyrano[3,2-]pyrrole derivatives in moderate to good yield using ferric hydrogensulphate, Fe(HSO4)3, as the catalyst.

  8. Synthesis of 2,2'-Dipyrryl Ketones from Pyrrole-2-carboxylic Acids with Trifluoroacetic Anhydride

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Se Hee; Lim, Jin Woo; Yu, Jin; Kim, Jae Nyoung [Chonnam National Univ., Gwangju (Korea, Republic of)

    2013-09-15

    An efficient synthesis of 2,2'-dipyrryl ketones has been carried out from pyrrole-2-carboxylic acids using trifluoroacetic anhydride (TFAA). Simultaneous generation of both mixed anhydride and 2-unsubstituted pyrrole, via facile decarboxylation with in-situ generated TFA, made their cross reaction (intermolecular Friedel-Crafts acylation) possible and efficient.

  9. 2-[(E-(1H-Pyrrol-2-ylmethylidenehydrazinyl]pyridine monohydrate

    Directory of Open Access Journals (Sweden)

    James L. Wardell

    2009-12-01

    Full Text Available The title hydrate, C10H10N4·H2O, shows a small twist in the hydrozone derivative, the dihedral angle between the pyridine and pyrrole rings being 11.08 (12°. The pyridine and pyrrole N atoms lie to the same side of the molecule being sustained in place by hydrogen-bonding interactions with the water molecule. Further intermolecular O—H...N and N—H...O hydrogen bonding leads to the formation of supramolecular arrays in the ab plane.

  10. Synthesis and recognition properties of higher order tetrathiafulvalene (TTF) calix n pyrroles (n=4-6)

    DEFF Research Database (Denmark)

    Park, J. S.; Bejger, C.; Larsen, K. R.;

    2012-01-01

    (Cl-, Br-, I-, CH3COO-, H2PO4-, and HSO4-) and neutral (1,3,5-trinitrobenzene (TNB) and 2,4,6-trinitrotoluene (TNT)) substrates revealed that as a general rule the calix[6]pyrrole derivative proved to be the most efficient molecular receptor for anions, while the calix[4]pyrrole congener proves most...... effective for the recognition of TNB and TNT. These findings are rationalized in terms of the number of electron rich TTF subunits and NH hydrogen bond donor groups within the series, as well as an ability to adopt conformations suitable for substrate recognition, and are supported by solid state structural...

  11. Hydrolytic study of the copolymer Poly pyrrole/ Polyethyleneglycol and Poly pyrrole synthesized by plasma; Estudio hidrolitico del copolimero polipirrol/polietilenglicol y polipirrol sintetizado por plasma

    Energy Technology Data Exchange (ETDEWEB)

    Colin, E.; Enriquez, M.A.; Olayo, M.G.; Cruz, G.J.; Carapia, L.; Romero, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Morales, J.; Olayo, R. [UAM-I, A.P. 55-534 Iztapalapa, Mexico D.F. (Mexico)

    2006-07-01

    In this work the study about the hydrolytic compatibility of semiconductor polymers, copolymer Poly pyrrole/ Polyethyleneglycol (PPy/PEG) and Poly pyrrole (PPy) for their possible use as biomaterials. The polymers were synthesized by plasma between 10 and 100 W, with discharges of splendor RF to 13.5 MHz with resistive coupling. The hydrolytic affinity was evaluated calculating the contact angle with solutions of NaCl, NaCl-MgSO{sub 4} and Krebs-Ringer. The results show a hydrophilicity increment due to the increase of the surface ruggedness with the synthesis energy. On the contrary, the crystallinity diminishes when increasing the power in PPy and it stays approximately constant in PPy/PEG. The electric conductivity presents a growth from 2 to 4 magnitude orders in function of the water content in the polymers. (Author)

  12. Identification of a new electron-transfer relaxation pathway in photoexcited pyrrole dimers.

    Science.gov (United States)

    Neville, Simon P; Kirkby, Oliver M; Kaltsoyannis, Nikolas; Worth, Graham A; Fielding, Helen H

    2016-04-21

    Photoinduced electron transfer is central to many biological processes and technological applications, such as the harvesting of solar energy and molecular electronics. The electron donor and acceptor units involved in electron transfer are often held in place by covalent bonds, π-π interactions or hydrogen bonds. Here, using time-resolved photoelectron spectroscopy and ab initio calculations, we reveal the existence of a new, low-energy, photoinduced electron-transfer mechanism in molecules held together by an NH⋯π bond. Specifically, we capture the electron-transfer process in a pyrrole dimer, from the excited π-system of the donor pyrrole to a Rydberg orbital localized on the N-atom of the acceptor pyrrole, mediated by an N-H stretch on the acceptor molecule. The resulting charge-transfer state is surprisingly long lived and leads to efficient electronic relaxation. We propose that this relaxation pathway plays an important role in biological and technological systems containing the pyrrole building block.

  13. Determination of solvation and binding site profile within electropolymerised poly(pyrrole-N-propionic acid)

    DEFF Research Database (Denmark)

    Glidle, A.; Swann, M.J.; Gadegaard, Nikolaj;

    2000-01-01

    Specular neutron reflectivity measurements were performed on electropolymerised films of poly(pyrrole-N-propionic acid) to determine the degree to which the solvents are capable of supporting biological macromolecules can penetrate the polymer film. The permeation profile of Ni2+ ions which chelate...

  14. Synthesis of Iso-condensed Heteroaromatic Pyrroles and Their Application in the Preparation of Conducting Polymers

    Institute of Scientific and Technical Information of China (English)

    Chin-Kang Sha; Su-Ya Cheng; Yuan-Liang Kuo; Liu Chia-Lin; V. Raghukumar

    2004-01-01

    Iso-condensed heteroaromatic pyrroles 1 are 10 -electron aromatic compounds. They are of interest from both theoretical and synthetic points of view. They are the cyclic analogues of heteroaromatic ortho-quinodimethanes 2, and can react with dienophiles in a Diels-Alder reaction to give the synthetically useful cycloadducts 3. Many of them are also of potential pharmaceutical importance because they are isosteric with indoles. Iso-condensed heteroaromatic pyrroles 1 can be used also as the monomers for the synthesis of new conducting polymers 5 with special properties and characteristics. However, the methods for the efficient preparation of the iso-condensed heteroaromatic pyrroles are quite limited. Iso-condensed heteroaromatic pyrroles are generally unstable in acidic conditions and are easily oxidized by air. In our laboratories, we developed three methods for the preparation of this labile heterocyclic ring system under acidic, neutral, and basic conditions.1 Synthesis of the conjugated systems such as 6 for OLED applications will also be discussed.

  15. A Facile Synthesis of Polysubstituted Pyrroles by One-Pot Three-Component Reaction

    OpenAIRE

    Anaraki-Ardakani, Hossein; Noei, Maziar; Karbalaei-Harofteh, Mina; Zomorodbakhsh, Shahab

    2012-01-01

    A new and efficient one-pot synthesis of polysubstituted pyrrole derivatives by three-component reaction between dialkyl acetylenedicarboxylates, triphenylphosphine, 2-aminopyridin derivatives in the presence of arylglyoxals is described. The reactions were performed in dichloromethane at room temperature and neutral conditions and afforded high yields of products.

  16. Synthesis of Dihydropyrrolizine and Tetrahydroindolizine Scaffolds from Pyrroles by Titanocene(III) Catalysis.

    Science.gov (United States)

    Hildebrandt, Sven; Gansäuer, Andreas

    2016-08-01

    A synthetic approach to dihydropyrrolizine and tetrahydroindolizine scaffolds from pyrroles has been developed. The key step, a titanocene(III)-catalyzed radical arylation that proceeds by C-H functionalization is atom-economical and tolerates a large variety of functional groups. The reaction is therefore attractive for the swift assembly of functional and structural diversity. PMID:27383638

  17. Identification of a new electron-transfer relaxation pathway in photoexcited pyrrole dimers

    Science.gov (United States)

    Neville, Simon P.; Kirkby, Oliver M.; Kaltsoyannis, Nikolas; Worth, Graham A.; Fielding, Helen H.

    2016-04-01

    Photoinduced electron transfer is central to many biological processes and technological applications, such as the harvesting of solar energy and molecular electronics. The electron donor and acceptor units involved in electron transfer are often held in place by covalent bonds, π-π interactions or hydrogen bonds. Here, using time-resolved photoelectron spectroscopy and ab initio calculations, we reveal the existence of a new, low-energy, photoinduced electron-transfer mechanism in molecules held together by an NH⋯π bond. Specifically, we capture the electron-transfer process in a pyrrole dimer, from the excited π-system of the donor pyrrole to a Rydberg orbital localized on the N-atom of the acceptor pyrrole, mediated by an N-H stretch on the acceptor molecule. The resulting charge-transfer state is surprisingly long lived and leads to efficient electronic relaxation. We propose that this relaxation pathway plays an important role in biological and technological systems containing the pyrrole building block.

  18. Ferrocene-functionalized 4-(2,5-Di(thiophen-2-yl)-1H-pyrrol-1-yl)aniline: a novel design in conducting polymer-based electrochemical biosensors.

    Science.gov (United States)

    Ayranci, Rukiye; Demirkol, Dilek Odaci; Ak, Metin; Timur, Suna

    2015-01-01

    Herein, we report a novel ferrocenyldithiophosphonate functional conducting polymer and its use as an immobilization matrix in amperometric biosensor applications. Initially, 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)amidoferrocenyldithiophosphonate was synthesized and copolymerized with 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzenamine at graphite electrodes. The amino groups on the polymer were utilized for covalent attachment of the enzyme glucose oxidase. Besides, ferrocene on the backbone was used as a redox mediator during the electrochemical measurements. Prior to the analytical characterization, optimization studies were carried out. The changes in current signals at +0.45 V were proportional to glucose concentration from 0.5 to 5.0 mM. Finally, the resulting biosensor was applied for glucose analysis in real samples and the data were compared with the spectrophotometric Trinder method. PMID:25591169

  19. Pyrrolo[3,2-b]pyrrole-Based Copolymers as Donor Materials for Organic Photovoltaics

    International Nuclear Information System (INIS)

    A new accepter unit, pyrrolo[3,2-b]pyrrole-2,5-dione, was prepared and utilized for the synthesis of the conjugated polymers containing electron donor-acceptor pair for OPVs. Pyrrolo[3,2-b]pyrrole-2,5-dione unit, regioisomer of the known pyrrolo[3,4-c]pyrrole-1,4-dione, is originated from the structure of stable synthetic pigment. The new conjugated polymers with 1,4-diphenylpyrrolo[3,2-b]pyrrole-2,5-dione, thiophene and carbazole were synthesized using Suzuki polymerization to generate P1 and P2. The solid films of P1 and P2 show absorption bands with maximum peaks at about 377, 554 and 374, 542 nm and the absorption onsets at 670 and 674 nm, corresponding to band gaps of 1.85 and 1.84 eV, respectively. To improve the hole mobility of the polymer with 1,4-bis(4-butylphenyl)-pyrrolo[3,2-b]-pyrrole-2,5-dione unit, which was previously reported by us, the butyl group at the 4-positions of the N-substituted phenyl group was substituted with hydrogen and methyl group. The field-effect hole mobility of P2 is 9.6 Χ 10-5 cm2/Vs. The device with P2:PC71BM (1:2) showed VOC value of 0.84 V, JSC value of 5.10 mA/cm2, and FF of 0.33, giving PCE of 1.42%

  20. Biofabrication Using Pyrrole Electropolymerization for the Immobilization of Glucose Oxidase and Lactate Oxidase on Implanted Microfabricated Biotransducers

    Directory of Open Access Journals (Sweden)

    Christian N. Kotanen

    2014-03-01

    Full Text Available The dual responsive Electrochemical Cell-on-a-Chip Microdisc Electrode Array (ECC MDEA 5037 is a recently developed electrochemical transducer for use in a wireless, implantable biosensor system for the continuous measurement of interstitial glucose and lactate. Fabrication of the biorecognition membrane via pyrrole electropolymerization and both in vitro and in vivo characterization of the resulting biotransducer is described. The influence of EDC-NHS covalent conjugation of glucose oxidase with 4-(3-pyrrolyl butyric acid (monomerization and with 4-sulfobenzoic acid (sulfonization on biosensor performance was examined. As the extent of enzyme conjugation was increased sensitivity decreased for monomerized enzymes but increased for sulfonized enzymes. Implanted biotransducers were examined in a Sprague-Dawley rat hemorrhage model. Resection after 4 h and subsequent in vitro re-characterization showed a decreased sensitivity from 0.68 (±0.40 to 0.22 (±0.17 µA·cm−2·mM−1, an increase in the limit of detection from 0.05 (±0.03 to 0.27 (±0.27 mM and a six-fold increase in the response time from 41 (±18 to 244 (±193 s. This evidence reconfirms the importance of biofouling at the bio-abio interface and the need for mitigation strategies to address the foreign body response.

  1. Use of Graphite Oxide and Graphene Oxide as Catalysts in the Synthesis of Dipyrromethane and Calix[4]pyrrole

    Directory of Open Access Journals (Sweden)

    Sweta Mishra

    2011-08-01

    Full Text Available Graphite oxide and graphene oxides have been used as solid catalysts for the synthesis of 5,5-dialkyldipyrromethanes and calix[4]pyrroles in organic and aqueous solutions at room temperature.

  2. Dichloridobis(4-pyridylmethyl 1H-pyrrole-2-carboxylate-κNzinc

    Directory of Open Access Journals (Sweden)

    Guilong Zhang

    2012-03-01

    Full Text Available In the title molecule, [ZnCl2(C11H10N2O22], the ZnII ion, situated on a twofold axis, is in a distorted tetrahedral coordination environment formed by two chloride anions and two pyridine N atoms of the two organic ligands. In the pyrrole-2-carboxylate unit, the pyrrole N—H group and the carbonyl group point approximately in the same direction. The dihedral angle between the two pyridine rings is 54.8 (3°. The complex molecules are connected into chains extending along [101] by N—H...Cl hydrogen bonds. The chains are further assembled into (-101 layers by C—H...O and C—H...Cl interactions.

  3. Ab initio multiple cloning simulations of pyrrole photodissociation: TKER spectra and velocity map imaging.

    Science.gov (United States)

    Makhov, Dmitry V; Saita, Kenichiro; Martinez, Todd J; Shalashilin, Dmitrii V

    2015-02-01

    We report a detailed computational simulation of the photodissociation of pyrrole using the ab initio Multiple Cloning (AIMC) method implemented within MOLPRO. The efficiency of the AIMC implementation, employing train basis sets, linear approximation for matrix elements, and Ehrenfest configuration cloning, allows us to accumulate significant statistics. We calculate and analyze the total kinetic energy release (TKER) spectrum and Velocity Map Imaging (VMI) of pyrrole and compare the results directly with experimental measurements. Both the TKER spectrum and the structure of the velocity map image (VMI) are well reproduced. Previously, it has been assumed that the isotropic component of the VMI arises from long time statistical dissociation. Instead, our simulations suggest that ultrafast dynamics contributes significantly to both low and high energy portions of the TKER spectrum. PMID:25523235

  4. The electropolymerization of pyrrole at a CuNi electrode: corrosion protection properties

    Energy Technology Data Exchange (ETDEWEB)

    Fenelon, Anna M.; Breslin, Carmel B

    2003-12-01

    Pyrrole was successfully electropolymerized at a copper-nickel electrode in a near-neutral sodium oxalate solution containing Cu{sup 2+} cations to generate a homogenous and adherent polypyrrole film. The presence of the Cu{sup 2+} ions increased both the rate of the electropolymerization reaction and the adherence of the polymer at the CuNi interface. In the absence of these cations, oxidation of the electrode occurred generating a nickel-rich layer that was not sufficiently conducting, under the electropolymerization conditions employed, to facilitate the electron-transfer reaction and the electropolymerization of pyrrole. These films remained stable and exhibited significant corrosion protection properties in acidified and neutral 0.1 mol dm{sup -3} NaCl solutions even on polarization of the electrodes to high anodic potentials.

  5. 3-/3,5-Pyrrole-substituted BODIPY derivatives and their photophysical and electrochemical studies

    Indian Academy of Sciences (India)

    KARTHIKA J KADASSERY; AKANKSHA NIMESH; SANOJ RAJ; NEERAJ AGARWAL

    2016-09-01

    Nucleophilic substitution on 3-bromo/3,5-dibromo-4,4'-difluoro-8-(aryl)-4-bora-3a,4a-diaza-sindacene (BODIPY), substituted with anisyl or thienyl at meso positions, with neat pyrrole afforded the mono and di-pyrrole substituted BODIPYs 1–4 in good yields. Large bathochromic shifts, upto ∼180 nm in absorption maxima (581–682 nm), and fluorescence maxima (606–695 nm) were observed for these BODIPYs. Absorption and fluorescence properties were studied in different solvents to compare the effect of mono and di substitution on BODIPY. The Lippert-Mataga equations were used which predict strong polarization of monosubstituted BODIPYs. Electrochemical studies were carried out to find the oxidation potential and HOMO energy levels were calculated. Theoretical studies of 1–4 provide the insight on the electron density distribution in 1–4. Theoretical and experimental photo-physical studies in different solvents were correlated to findthe substituent effects on BODIPY.

  6. tert-Butyl 2-borono-1H-pyrrole-1-carboxylate

    Directory of Open Access Journals (Sweden)

    Zheng Zhong

    2009-04-01

    Full Text Available In the crystal structure of the title compound, C9H14BNO4, the boronic acid group and carbamate groups are nearly co-planar with the pyrrole ring, making dihedral angles of 0.1 (2 and 2.2 (2°, respectively. Intramolecular and intermolecular O—H...O hydrogen bonds help to stabilize the structure, the latter interaction leading to inversion dimers..

  7. A joint experimental and computational investigation on the thermochemistry of (nitrophenyl)pyrroles

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Ana Filipa L.O.M. [Centro de Investigacao em Quimica, Department of Chemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal); Ribeiro da Silva, Manuel A.V., E-mail: risilva@fc.up.p [Centro de Investigacao em Quimica, Department of Chemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal)

    2010-08-15

    This paper reports the standard (p{sup o} = 0.1 MPa) molar enthalpies of formation, in the gaseous phase, {Delta}{sub f}H{sub m}{sup 0}(g), at T = 298.15 K, of 1-(2-nitrophenyl)pyrrole and of 1-(4-nitrophenyl)pyrrole as (235.7 {+-} 2.7) kJ . mol{sup -1} and (205.5 {+-} 2.5) kJ . mol{sup -1}, respectively. These values were derived from experimental thermodynamic parameters, namely from the standard (p{sup o} = 0.1 MPa) molar enthalpies of formation, in the crystalline phase, {Delta}{sub f}H{sub m}{sup 0}(cr), at T = 298.15 K, obtained from the standard molar enthalpies of combustion, {Delta}{sub c}H{sub m}{sup 0}, measured by static-bomb combustion calorimetry, and from the standard molar enthalpies of sublimation, at T = 298.15 K, determined from the temperature-vapour pressure dependence, obtained by the Knudsen mass loss effusion method. Additionally, the gas-phase enthalpies of formation were estimated by G3(MP2)//B3LYP calculations, using several gas-phase working reactions, and were compared with the experimental determined ones. Experimental and theoretical results are in very good agreement and show that 1-(4-nitrophenyl)pyrrole is thermodynamically more stable than the 2-isomer. This composite approach was also used to estimate the gas-phase enthalpy of formation of the 1-(3-nitrophenyl)pyrrole.

  8. Pyrrole Azocrown Ethers. Synthesis, Complexation, Selective Lead Transport and Ion-Selective Membrane Electrode Studies

    OpenAIRE

    Luboch, Elzbieta; Wagner-Wysiecka, Ewa; Fainerman-Melnikova, Marina; Lindoy, Leonard F.; Biernat, Jan F.

    2006-01-01

    Abstract New 21-membered lipophilic crown ethers, each incorporating a pyrrole unit and two azo groups as macrocyclic ring components, have been synthesized. The complexation behavior of these and two further macrocycles has been investigated in acetonitrile. These ligand systems have been employed as ionophores in transport experiments involving the competitive transport behavior of an equimolar mixture of Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Ag+ and Pb2+ across a water (pH 4.9)/chlorof...

  9. FABRICATION OF HIGHLY HYDROPHOBIC FILMS OF POLY(3-HEXADECYL PYRROLE) NANOPARTICLES BY LANGMUIR-BLODGETT TECHNIQUE

    Institute of Scientific and Technical Information of China (English)

    Zhen-min Hong; Gao-quan Shi; Xu-feng Wu; Liang-ti Qu

    2006-01-01

    Thin films of poly(3-hexadecyl pyrrole) (P3HDP) nanoparticles have been fabricated by using Langmuir-Blodgett film deposition technique. The structures and morphology of the films were studied by using infrared spectroscopy, scanning and transmission microscopes. The experimental results demonstrated that the nanoparticles were formed by self-assembling P3HDP at air-water surface. The water contact angles of these films with different deposition layers were measured to be as high as 110°.

  10. Interaction of derived polymers from pyrrole with biocompatible solutions; Interaccion de polimeros derivados de pirrol con soluciones biocompatibles

    Energy Technology Data Exchange (ETDEWEB)

    Lopez G, O. G.

    2010-07-01

    This work presents a study about the synthesis by plasma, the electric properties and superficial interaction of polymers derived from pyrrole doped with Iodine with potential use as bio material. Poly-pyrrole is a semiconductor and biocompatible polymer with potential application in the development of artificial muscles and implants where the electric interaction between cells and material is an important variable. The syntheses were made at 13.5 MHz in a glass tubular reactor of 1500 cm{sup 3} with electrodes of 6.5 cm diameter and stainless steel flanges. An electrode was connected to the RF terminal of the power supply that is combined with a matching coupling resistance. The monomer and dopant used in this work were pyrrole and Iodine respectively, in closed containers. They were vaporized and injected separately into the reactor at room temperature and 0.1 mbar. The vapors of the reagents mixed freely in the reactor. The synthesis time was 240 min at 40, 60, 80 and 100 W. The polymers were obtained as thin films adhered to the reactor walls. The films were washed and swollen with distilled water and removed from the reactor walls with a small spatula. The polymers were irradiated with gamma rays at 18 and 22 KGy. Due to the fact that the doses are cumulative, the final dose applied was 40 KGy. The polymers characterization was carried out by Fourier Transform Infrared Spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy, contact angle, electrical conductivity and X-ray diffraction. The analyses indicates that the polymers have very similar structure in almost the entire power range, showing C-O, C=C, C-H, O-H, N-H bonds with a predominantly amorphous structure. The TGA analyses showed that the material has 4 or 5 loses of material. The first one starts after that 115 C except for the material irradiated at 40 KGy, this one begins in 87 C, the second one is in the interval of 196 and 295 C, the third one between 311 and 500 C, and the

  11. A soluble conducting polymer: 1-Phenyl-2,5-di(2-thienyl)-1H-pyrrole and its electrochromic application

    Energy Technology Data Exchange (ETDEWEB)

    Tarkuc, S. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Sahmetlioglu, E. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Department of Chemistry, Nigde University, 51100 Nigde (Turkey); Tanyeli, C. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Akhmedov, I.M. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey); Toppare, L. [Department of Chemistry, Middle East Technical University, 06531 Ankara (Turkey)]. E-mail: toppare@metu.edu.tr

    2006-07-28

    A thiophene-functionalized monomer 1-phenyl-2,5-di(2-thienyl)-1H-pyrrole (PTP) was synthesized. The chemical polymerization of PTP (CPTP) was realized by using FeCl{sub 3} as the oxidant. The structures of both the monomer and the soluble polymer (CPTP) were investigated by Nuclear Magnetic Resonance ({sup 1}H and {sup 13}C NMR) and Fourier Transform Infrared (FTIR). The average molecular weight of the chemically synthesized polymer was determined by gel permeation chromatography (GPC) as Mn = 7.2 x 10{sup 3}. The electrochemical oxidative polymerization of PTP was carried out via constant-potential electrolysis. Characterizations of the resulting polymer were done by cyclic voltammetry (CV), FTIR, Scanning Electron Microscopy (SEM) and UV-vis Spectroscopy. The conductivity of sample was measured by four-probe technique. Moreover, the spectroelectrochemical and electrochromic properties of the polymer film were investigated. Spectroelectrochemical analysis of P(PTP) revealed electronic transitions at 413, 577 and 884 nm corresponding to {pi}-{pi}* transition, polaron, and bipolaron band formations, respectively. Kinetic studies evaluated the switching ability of the P(PTP); the percent transmittance T% was found as 27%. The homopolymer of PTP was used to construct dual-type polymer electrochromic devices (ECDs) against poly(3,4-ethylenedioxythiophene) (PEDOT). Spectroelectrochemistry, electrochromic switching and open circuit stability of the devices were investiga0009t.

  12. A soluble conducting polymer: 1-Phenyl-2,5-di(2-thienyl)-1H-pyrrole and its electrochromic application

    International Nuclear Information System (INIS)

    A thiophene-functionalized monomer 1-phenyl-2,5-di(2-thienyl)-1H-pyrrole (PTP) was synthesized. The chemical polymerization of PTP (CPTP) was realized by using FeCl3 as the oxidant. The structures of both the monomer and the soluble polymer (CPTP) were investigated by Nuclear Magnetic Resonance (1H and 13C NMR) and Fourier Transform Infrared (FTIR). The average molecular weight of the chemically synthesized polymer was determined by gel permeation chromatography (GPC) as Mn = 7.2 x 103. The electrochemical oxidative polymerization of PTP was carried out via constant-potential electrolysis. Characterizations of the resulting polymer were done by cyclic voltammetry (CV), FTIR, Scanning Electron Microscopy (SEM) and UV-vis Spectroscopy. The conductivity of sample was measured by four-probe technique. Moreover, the spectroelectrochemical and electrochromic properties of the polymer film were investigated. Spectroelectrochemical analysis of P(PTP) revealed electronic transitions at 413, 577 and 884 nm corresponding to π-π* transition, polaron, and bipolaron band formations, respectively. Kinetic studies evaluated the switching ability of the P(PTP); the percent transmittance T% was found as 27%. The homopolymer of PTP was used to construct dual-type polymer electrochromic devices (ECDs) against poly(3,4-ethylenedioxythiophene) (PEDOT). Spectroelectrochemistry, electrochromic switching and open circuit stability of the devices were investigated

  13. Electrochromic and electrochemical properties of 3-pyridinyl and 1,10-phenanthroline bearing poly(2,5-di(2-thienyl)-1H-pyrrole) derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jaeyoung; Ik Son, Jung; Shim, Yoon-Bo [Department of Chemistry, Pusan National University, Keumjeong-ku, Busan 609-735 (Korea)

    2010-07-15

    This study examined a highly efficient synthetic route and characterization of two derivatives of 2,5-di(2-thienyl)-1H-pyrrole that incorporated 3-pyridinyl and 1,10-phenanthroline moieties in the central pyrrole ring. The electrically conductive polyPTPy and polyPhenTPy films were synthesized through electropolymerization on a glassy carbon electrode in a 0.1 M TBAP/dichloromethane solution. The polymer films were characterized using cyclic voltammetry (CV), in situ conductivity measurements, and in situ spectroelectrochemistry. The redox peaks of the polyPTPy and polyPhenTPy films were observed at 0.96/0.66 and 0.89/0.73 V, respectively. The maximum conductivities of polyPTPy and polyPhenTPy were 6.5 x 10{sup -2} and 9.2 x 10{sup -2} S/cm at 1.4 V. The spectroelectrochemical analysis showed that the polyPTPy film was brownish-yellow color ({lambda}{sub max}=430 nm) in the neutral state and dark blue (1.4 V) in the fully oxidized state. Similarly, polyPhenTPy was greenish-yellow color ({lambda}{sub max}=451 nm) in the neutral state and light blue (1.4 V) in the fully oxidized state. The polymer films exhibited a fast optical switching time within 1.0 s. The electrochemical and spectroelectrochemical characterizations of these films revealed that the materials were highly electroactive and robust in terms of electrochromics. (author)

  14. Spectral, IR and magnetic studies of Mn(II), Co(II), Ni(II) and Cu(II) complexes with pyrrole-2-carboxyaldehyde thiosemicarbazone (L)

    Science.gov (United States)

    Chandra, Sulekh; Kumar, Anil

    2007-11-01

    Mn(II), Co(II), Ni(II) and Cu(II) complexes are synthesized with thiosemicarbazone (L) derived from pyrrole-2-carboxyaldehyde. These complexes are characterized by elemental analysis, molar conductance, magnetic susceptibility measurement, mass, IR, electronic and EPR spectral studies. The molar conductance measurement of the complexes in DMSO indicates that the complexes are non-electrolyte except Co(L) 2(NO 3) 2 and Ni(L) 2(NO 3) 2 complexes which are 1:2 electrolyte. All the complexes are of high-spin type. On the basis of spectral studies an octahedral geometry may be assigned for Mn(II), Co(II) and Ni(II) complexes except Co(L) 2(NO 3) 2 and Ni(L) 2(NO 3) 2 which are of tetrahedral geometry. A tetragonal geometry may be suggested for Cu(II) complexes.

  15. Biological activity of two new pyrrole derivatives against stored-product species: influence of temperature and relative humidity.

    Science.gov (United States)

    Boukouvala, M C; Kavallieratos, N G; Athanassiou, C G; Hadjiarapoglou, L P

    2016-08-01

    Members of the pyrrole group are likely to have interesting properties that merit additional investigation as insecticides at the post-harvest stages of agricultural commodities. In the present work, the insecticidal effect of two new pyrrole derivatives, ethyl 3-(benzylthio)-4,6-dioxo-5-phenyl-2,4,5,6-tetrahydropyrrolo[3,4-c]pyrrole-carboxylate (3i) and isopropyl 3-(benzylthio)-4,6-dioxo-5-phenyl-2,4,5,6-tetrahydropyrrolo[3,4-c]pyrrole-carboxylate (3k) were studied as stored-wheat protectants against two major stored-product insect species, the confused flour beetle, Tribolium confusum Jaquelin du Val adults and larvae and the Mediterranean flour moth, Ephestia kuehniella Zeller larvae at different doses (0.1, 1 and 10 ppm), exposure intervals (7, 14 and 21 days), temperatures (20, 25 and 30°C) and relative humidity (55 and 75%) levels. For T. confusum adults, in the case of the pyrrole derivative 3i, mortality was low and it did not exceed 32.2% in wheat treated with 10 ppm 3i at 30°C and 55% relative humidity. Progeny production was very low (insecticidal effect, but this effect is moderated by the exposure, the target species, the temperature and the relative humidity. PMID:27087458

  16. Electrochemical polymerization of pyrrole over AZ31 Mg alloy for biomedical applications

    International Nuclear Information System (INIS)

    Highlights: ► Polymerization of pyrrole over AZ31 Mg was carried out using cyclic voltammetry. ► Pyrrole concentration was optimized to accomplish the adherent and uniform coating. ► Effect of monomer concentration on the surface morphology was discussed. ► Corrosion resistance of AZ31 Mg in SBF was studied as a function of Py concentration. ► PPy coated AZ31 Mg alloy exhibited enhanced corrosion resistance at 0.25 M of Py. -- Abstract: Electrochemical polymerization of pyrrole (Py) from aqueous salicylate solution over AZ31 Mg alloy was carried out using cyclic voltammetry (CV). The effect of monomer concentration on the surface and electrochemical corrosion in simulated body fluid (SBF) were analysed. Attenuated total reflection-infrared (ATR-IR) spectra showed the characteristic ring stretching peaks for polypyrrole (PPy). Scanning electron microscopy (SEM) and atomic force microscopy (AFM) studies exhibited typical cauliflower morphology with rough surface for PPy coated AZ31 Mg alloy. Open circuit potential measurement and potentiodynamic polarization studies revealed that the coating prepared using 0.25 M of Py had positive shift of about 120 mV in corrosion potential and lower corrosion current density (0.03 mA/cm2) compared to other concentrations and uncoated AZ31 Mg alloy (0.25 mA/cm2). Electrochemical impedance spectroscopic (EIS) studies of uncoated and PPy coated Mg alloy in SBF revealed three-time constants behaviour with about one order of increment in impedance value for 0.25 M of Py

  17. Quantification of CH-π Interactions Using Calix[4]pyrrole Receptors as Model Systems

    Directory of Open Access Journals (Sweden)

    Gemma Aragay

    2015-09-01

    Full Text Available We describe the use of two series of aryl-extended calix[4]pyrrole receptors bearing two and four electronically tunable phenyl groups, respectively, in their meso-positions as model systems for the quantification of CH-π interactions in solution. The “four-wall” and the “two-wall” receptors formed thermodynamically stable 1:1 complexes in acetonitrile solution with both trimethylamine N-oxide and trimethylphosphine P-oxide as guests. The complexes were mainly stabilized by the formation of four convergent hydrogen bonds between the oxygen atom of the guests and the pyrrole NHs of the host. In general, the N-oxide produced thermodynamically more stable hydrogen bonding interactions than the P-oxide. Upon guest binding, the receptors adopted the cone conformation and the methyl groups of the included guests engaged in CH-π interactions with the aromatic walls. We show that the modification of the electronic properties of the aromatic surfaces, in any of the receptor series, did not have a significant impact in the measured binding affinities for a given guest. However, the larger binding affinities determined for the “four-wall” receptors in comparison to the “two-wall” counterparts supported the importance of CH-π interactions on guest complexation. The strength of the CH-π interactions present in the inclusion complexes was quantified employing the octamethyl calix[4]pyrrole as reference. We determined an average magnitude of ~1 kcal·mol−1 for each CH-π interaction. The CH-π interactions featured a reduced electrostatic nature and thus dispersion forces were assigned as main contributors of their strength.

  18. Access to pyrrolo-pyridines by gold-catalyzed hydroarylation of pyrroles tethered to terminal alkynes

    Directory of Open Access Journals (Sweden)

    Elena Borsini

    2011-10-01

    Full Text Available In a simple procedure, the intramolecular hydroarylation of N-propargyl-pyrrole-2-carboxamides was accomplished with the aid of gold(III catalysis. The reaction led to differently substituted pyrrolo[2,3-c]pyridine and pyrrolo[3,2-c]pyridine derivatives arising either from direct cyclization or from a formal rearrangement of the carboxamide group. Terminal alkynes are essential to achieve bicyclic pyrrolo-fused pyridinones by a 6-exo-dig process, while the presence of a phenyl group at the C–C triple bond promotes the 7-endo-dig cyclization giving pyrrolo-azepines.

  19. Thermal Diffusivity Measurement of Poly pyrrole-Chitosan Composite by Photoacoustic Technique

    International Nuclear Information System (INIS)

    Thermal diffusivity is a physical quantity that represents an intrinsic property for a material and indicates how fast heat propagates through a sample. The photoacoustic (PA) technique has recently been recognized as a powerful and reliable experimental technique in measuring thermal diffusivity. This effect is described as the periodic heating generated in the sample by a nonradiative deexcitation process due to the absorption of a modulated light source [1]. In present work, the conducting polymer composite films of poly pyrrole-chitosan (PPy- CHI) were synthesized by electrochemical polymerization method. The electrical conductivity and thermal diffusivity of composite film were studied as a function of electro polymerization conditions. (author)

  20. Low frequency ac conduction and dielectric relaxation in poly(N-methyl pyrrole)

    Indian Academy of Sciences (India)

    Amarjeet K Narula; Ramadhar Singh; Subhas Chandra

    2000-06-01

    The ac conductivity and dielectric constant of poly(N-methyl pyrrole) thin films have been investigated in the temperature range 77–350 K and in the frequency range 102–106 Hz. The well defined loss peaks have been observed in the temperature region where measured ac conductivity approaches dc conductivity. These loss peaks are associated with the hopping of the charge carriers. The frequency and temperature dependence of ac conductivity have been qualitatively explained by considering the contribution from two mechanisms; one giving a linear dependence of conductivity on frequency and other having distribution of relaxation times giving rise to broad dielectric loss peak.

  1. Organocatalytic Enantioselective Aza-Friedel-Crafts Reaction of Cyclic Ketimines with Pyrroles using Imidazolinephosphoric Acid Catalysts.

    Science.gov (United States)

    Nakamura, Shuichi; Matsuda, Nazumi; Ohara, Mutsuyo

    2016-07-01

    Organocatalytic enantioselective aza-Friedel-Crafts reactions of cyclic ketimines with pyrroles or indoles were catalyzed by imidazoline/phosphoric acid catalysts. The reaction was applied to various 3H-indol-3-ones to afford products in excellent yields and enantioselectivities. The chiral catalysts can be recovered by a single separation step using column chromatography and are reusable without further purification. Based on the experimental investigations, a possible transition state has been proposed to explain the origin of the asymmetric induction. PMID:27124556

  2. Sustainable Pathways to Pyrroles through Iron-Catalyzed N-Heterocyclization from Unsaturated Diols and Primary Amines.

    Science.gov (United States)

    Yan, Tao; Barta, Katalin

    2016-09-01

    Pyrroles are prominent scaffolds in pharmaceutically active compounds and play an important role in medicinal chemistry. Therefore, the development of new, atom-economic, and sustainable catalytic strategies to obtain these moieties is highly desired. Direct catalytic pathways that utilize readily available alcohol substrates have been recently established; however, these approaches rely on the use of noble metals such as ruthenium or iridium. Here, we report on the direct synthesis of pyrroles using a catalyst based on the earth-abundant and inexpensive iron. The method uses 2-butyne-1,4-diol or 2-butene-1,4-diol that can be directly coupled with anilines, benzyl amines, and aliphatic amines to obtain a variety of N-substituted pyrroles in moderate-to-excellent isolated yields.

  3. Sustainable Pathways to Pyrroles through Iron-Catalyzed N-Heterocyclization from Unsaturated Diols and Primary Amines.

    Science.gov (United States)

    Yan, Tao; Barta, Katalin

    2016-09-01

    Pyrroles are prominent scaffolds in pharmaceutically active compounds and play an important role in medicinal chemistry. Therefore, the development of new, atom-economic, and sustainable catalytic strategies to obtain these moieties is highly desired. Direct catalytic pathways that utilize readily available alcohol substrates have been recently established; however, these approaches rely on the use of noble metals such as ruthenium or iridium. Here, we report on the direct synthesis of pyrroles using a catalyst based on the earth-abundant and inexpensive iron. The method uses 2-butyne-1,4-diol or 2-butene-1,4-diol that can be directly coupled with anilines, benzyl amines, and aliphatic amines to obtain a variety of N-substituted pyrroles in moderate-to-excellent isolated yields. PMID:27493031

  4. CHEMISTRY OF SULFONYLMETHYL ISOCYANIDES .37. SYNTHESIS OF 3,4-DISUBSTITUTED PYRROLES BEARING SUBSTITUENTS OF ELECTRON-WITHDRAWING AND/OR ELECTRON-DONATING NATURE

    NARCIS (Netherlands)

    VANLEUSEN, D; VANECHTEN, E; van Leusen, A.M.

    1992-01-01

    The synthesis is described of a series of 3,4-disubstituted pyrroles 8 from 1-isocyano-1-tosyl-1-alkenes and a variety of Michael donors. It is possible to use this method for the synthesis of pyrroles that bear no electron-withdrawing substitutents.

  5. Diethyl 2-amino-5-[(E-(1-methyl-1H-pyrrol-2-ylmethylideneamino]thiophene-3,4-dicarboxylate

    Directory of Open Access Journals (Sweden)

    Stéphane Dufresne

    2010-12-01

    Full Text Available The structure of the title compound, C16H19N3O4S, shows the planes described by the thiophene and the pyrroles are twisted by 17.06 (4°. Additionally, the structure shows the azomethine bond adopts the E configuration, while the pyrrole is disordered as a heterocycle flip [occupancy ratio 0.729 (5:0.271 (5]. The three-dimensional network is well packed and involves N–H...O hydrogen bonding and π–π stacking [centroid–centroid distance = 4.294 (8 Å].

  6. Synthesis of furans and pyrroles via migratory and double migratory cycloisomerization reactions of homopropargylic aldehydes and imines

    Science.gov (United States)

    Shiroodi, Roohollah Kazem; Vera, Claudia I. Rivera; Dudnik, Alexander S.; Gevorgyan, Vladimir

    2015-01-01

    A novel gold-catalyzed divergent sysnthesis of furans and pyrroles employing readily available homopropargylic aldehydes and imines have been developed. The regiochemical outcome of this reaction is dependent on the substituent on the terminal alkyne of substrate. Thus, substrates possessing alkyl and aryl substituent at the alkyne moiety produce 2,3,5-substituted furans and pyrroles via a migratory cycloisomerizaton reaction. Whereas, their silicon analogues are capable to undergo a double migratory process leading to 2,3,4-substituted heterocycles. PMID:26185336

  7. Ethyl (2E-2-cyano-3-(1-methyl-1H-pyrrol-2-ylprop-2-enoate

    Directory of Open Access Journals (Sweden)

    Abdullah M. Asiri

    2011-09-01

    Full Text Available The 15 non-H atoms of the title compound, C11H12N2O2, are approximately coplanar, the r.m.s. deviation being 0.145 Å. The major deviation from coplanarity is seen in a twist between the ethene (E configuration and pyrrole rings [C—C—N—C torsion angle = −8.26 (18°]. The carbonyl O and cyano N atoms are syn to each other. In the crystal, supramolecular linear tapes linked by C—H...O and C—H...N interactions are further connected by C—H...π(pyrrole interactions.

  8. Synthesis of Conductive PPy/SiO2 Aerogels Nanocomposites by In Situ Polymerization of Pyrrole

    Directory of Open Access Journals (Sweden)

    Daliana Muller

    2015-01-01

    Full Text Available Electrical conductive nanocomposite aerogels were synthesized through in situ oxidative polymerization of pyrrole (Py using ammonium persulfate (APS as an oxidizing agent in SiO2 gels. The effect of Py concentration on the electrical conductivity and physical and morphological properties of aerogels SiO2/PPy was evaluated. B.E.T. analysis indicated that the surface area of the composite SiO2/PPy decreases with increasing concentration of Py. CHN analysis showed an increase in the amount of PPy, from 13 wt.% to 23 wt.%, with increasing concentration of pyrrole synthesis. FTIR-ATR analysis of the composites revealed bands in the region of 1500–1400 cm−1, indicating the presence of the conductive polymer in the silica aerogel as well as the characteristic bands of Si-O-Si and Si-OH covalent bonds. TEM micrographs revealed the presence of particles of PPy with the increased size of the nanoparticles. The composites were successfully applied as passive components, in RC circuits, for low-pass frequency filters. The filters exhibited a cutoff frequency at approximately 435 Hz. The aerogels obtained in this work exhibited suitable electrical conductivity for use in various other applications in electronics.

  9. Polymers and copolymers of pyrrole and thiophene as electrodes in lithium cells

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, M.I.S. de; Mishima, H.T.; Mishima, B.A.L. de [Universidad Nacional de Santiago del Estero (Argentina). Inst. de Cs. Quimicas

    1997-07-01

    The performance of pyrrole and thiophene polymer electrodes in lithium cells has been examined in the lithium perchlorate-propylene carbonate electrolyte by cyclic voltammetry. Polypyrrole films were synthesized in `wet` and `dry` conditions; pyrrole and thiophene copolymers were prepared at different potentials and bilayers were prepared by sequential deposition of polythiophene (PTh) and polypyrrole (PPy) films. The polymers were cycled between 2.0V and 4.0V in the lithium cells. The effects of disconnecting the electrodes from the cell on the behaviour of the polymers regarding doping and coulombic efficiency were also studied. The cycling performance of the `wet` PPy is better than `dry` PPy, bilayer PTg/PPy and copolymers. No mixed behaviour was observed for a bilayer where the inner layer was polythiophene and the outer layer was polypyrrole with a thickness PP6/Pth ratio equal to ten. The copolymer prepared at 3.9V vs Li/Li{sup +} showed the higher energy capacity in Wh kg{sup -1} calculated from the anodic charge. (Author)

  10. Electrochemical Detection of Clenbuterol in Pig Liver at Pyrrole-DNA Modified Boron-doped Diamond Electrode

    Institute of Scientific and Technical Information of China (English)

    WU Jing; LI Xiao-li; WU Xu-mei; HUAN Shuang-yan; SHEN Guo-li; YU Ru-qin

    2005-01-01

    The direct detection of clenbuterol(CL) in pig liver without any extraction separation at a pyrrole-DNA modified boron-doped diamond(BDD) electrode is reported. The pyrrole-DNA modified BDD electrode has a strong electrocatalytic effect on the redox reaction of CL. One oxidization and two reduction peaks of CL appear at 340.2, 299.8 and 166.6 mV(versus SCE), respectively. The pyrrole polymer alone cannot electrocatalyze the above reaction at a BDD electrode; the electrocatalytic effect of a BDD electrode modified with DNA membrane is unsufficient for the analytical detection of CL; the replacement of boron-doped diamond by glass carbon makes the electrocatalytic reaction impossible; the redox process is pH dependent. The influences of various experimental parameters on the pyrrole-DNA modified BDD electrode were investigated. A sensitive cyclic voltammetric response for CL was obtained in a linear range from 3.4×10-6 to 5×10-4 mol/L with a detection limit of 8.5×10-7 mol/L. A mean recovery of 102.7% of CL in the pig liver sample solution and a reproducibility of 3.2% were obtained.

  11. Tetraaryl-, Pentaaryl-, and Hexaaryl-1,4-dihydropyrrolo 3,2-b pyrroles: Synthesis and Optical Properties

    DEFF Research Database (Denmark)

    Krzeszewski, M.; Thorsted, B.; Brewer, J.;

    2014-01-01

    Efficient conditions for the synthesis of tetra-, penta-, and hexasubstituted derivatives of 1,4-dihydropyrrolo[3,2-b]pyrrole were developed. The tetraaryl derivatives were obtained in a novel one-pot reaction among aromatic aldehydes, aromatic amines, and butane-2,3-dione. After a thorough exami...

  12. Pseudocapacitive Electrodes Produced by Oxidant-Free Polymerization of Pyrrole between the Layers of 2D Titanium Carbide (MXene).

    Science.gov (United States)

    Boota, Muhammad; Anasori, Babak; Voigt, Cooper; Zhao, Meng-Qiang; Barsoum, Michel W; Gogotsi, Yury

    2016-02-17

    Heterocyclic pyrrole molecules are in situ aligned and polymerized in the -absence of an oxidant between layers of the 2D Ti3C2Tx (MXene), resulting in high volumetric and gravimetric capacitances with capacitance retention of 92% after 25,000 cycles at a 100 mV s(-1) scan rate.

  13. Ruthenium(II)-catalyzed synthesis of pyrrole- and indole-fused isocoumarins by C-H bond activation in DMF and water

    Digital Repository Service at National Institute of Oceanography (India)

    Singh, K.S.; Sawant, S.G.; Dixneuf, P.H.

    : ChemCatChem, vol.8(6); 2016; 1046-1050 Ruthenium(II) catalysed synthesis of pyrrole and indole fused isocoumarins via C-H bond activation in DMF and water† Keisham S. Singh*,a Sneha G. Sawanta, Pierre H. Dixneuf*,b Abstract: Pyrrole and indole... isocoumarins from simple 1-methyl pyrrole-2- carboxylic acid and 1-methylindole-3-carboxylic acid via annulation with alkyne in the presence ruthenium(II) catalyst based on [RuCl2(p-cymene)]2 and Cu(OAc)2.H2O as oxidant in DMF. This ruthenium(II) catalysed...

  14. Outer-Sphere Mechanism in the Oxidation of Pyrrole-2- Carboxaldehyde by Hexacyanoferrate (III Complex.

    Directory of Open Access Journals (Sweden)

    Abd-Alhakeem H. Abu-Nawwas

    2014-01-01

    Full Text Available The kinetics and mechanism of base-catalyzed oxidation of pyrrole-2-carboxaldehyde with hexacyanoferrate (III is reported. The reaction showed first order with respect to aldahyde , alkali and hexaeyanoferrate(III. The kinetic data suggest that the oxidation involves the formation of an anion of the substrate undergoes oxidation with hexaeyanoferrate(III via outer sphere mechanism process. The free radical thus produced is further oxidized to form the final products. A suitable mechanism was proposed and rate law was derived as − d[Fe CN 6 ] 3− = 2k1k2 RC(OH2 [Fe CN 6 ] 3−[OH−] k−1 H2O

  15. ELECTRICALLY CONDUCTIVE COMPOSITE PREPARED BY ELECTROCHEMICAL POLYMERIZATION OF PYRROLE IN POLY- (p- PHENYLENE TEREPHTHALAMIDE ) MATRIX

    Institute of Scientific and Technical Information of China (English)

    BI Xiantong; PEI Qibing; HAN Baozhen; BAO Jingshen

    1991-01-01

    The preparation of PPy/PPTA conductive composite films by electrochemical method is presented.The first step is to cast a thin layer of poly (p-phenylene-terephthalamide)(PPTA)on a slice of Pt working electrode. The second step is to electrochemically polymerize pyrrole on the PPTA/Pt working electrode. Both of the electrical conductivity and the mechanical properties of the PPy/PPTA composite film are better than those of the pure PPy film, and the film has excellent flexibility at low temperature, even in liquid nitrogen.The SEM picture of the cross-section of PPy/PPTA composite film showed that the two components were well mixed.Cyclic voltammograms of PPy/PPTA film in aqueous solution showed that the conductive films could be reduced and reoxidized.

  16. Theoretical Study on Measure of Hydrogen Bonding Strength: R-C≡N…pyrrole Complexes

    Institute of Scientific and Technical Information of China (English)

    史福强; 安静仪; 俞稼镛

    2005-01-01

    The R-C≡N…pyrrole (R=H, CH3, CH2F, CHF2, CF3, NH2, BH2, OH, F, CH2Cl, CHCl2, CCl3, Li, Na) complexes were considered as the simple sample for measure of hydrogen bonding strength. Density functional theory B3LYP/6-311 + + G** level was applied to the optimization of geometries of complexes and monomers. Measure of hydrogen bonding strength based on geometrical and topological parameters, which were derived from the AIM theory, was analyzed. Additionally, natural bond orbital (NBO) analysis and frequency calculations were performed.From the computation results it was found that the electronic density at N-H bond critical points was also strictly correlated with the hydrogen bonding strength.

  17. Crystal structure of 1-benzyl-4-formyl-1H-pyrrole-3-carb-oxamide.

    Science.gov (United States)

    Zhong, Qi-Di; Hu, Sheng-Quan; Yan, Hong

    2016-02-01

    In the title compound, C13H12N2O2 (I), the mean planes of the pyrrole and benzyl rings are approximately perpendicular, forming a dihedral angle of 87.07 (4) °. There is an intra-molecular N-H⋯O hydrogen bond forming an S(7) ring motif. In the crystal, mol-ecules are linked via a pair of N-H⋯O hydrogen bonds forming inversion dimers. C-H⋯O hydrogen bonds link the dimers into chains along direction [10-1]. The chains are further linked by weak C-H⋯π inter-actions forming layers parallel to the ac plane. PMID:26958371

  18. Tumor Repression of VCaP Xenografts by a Pyrrole-Imidazole Polyamide.

    Directory of Open Access Journals (Sweden)

    Amanda E Hargrove

    Full Text Available Pyrrole-imidazole (Py-Im polyamides are high affinity DNA-binding small molecules that can inhibit protein-DNA interactions. In VCaP cells, a human prostate cancer cell line overexpressing both AR and the TMPRSS2-ERG gene fusion, an androgen response element (ARE-targeted Py-Im polyamide significantly downregulates AR driven gene expression. Polyamide exposure to VCaP cells reduced proliferation without causing DNA damage. Py-Im polyamide treatment also reduced tumor growth in a VCaP mouse xenograft model. In addition to the effects on AR regulated transcription, RNA-seq analysis revealed inhibition of topoisomerase-DNA binding as a potential mechanism that contributes to the antitumor effects of polyamides in cell culture and in xenografts. These studies support the therapeutic potential of Py-Im polyamides to target multiple aspects of transcriptional regulation in prostate cancers without genotoxic stress.

  19. State-specific tunneling lifetimes from classical trajectories: H-atom dissociation in electronically excited pyrrole

    Science.gov (United States)

    Xie, Weiwei; Domcke, Wolfgang; Farantos, Stavros C.; Grebenshchikov, Sergy Yu.

    2016-03-01

    A trajectory method of calculating tunneling probabilities from phase integrals along straight line tunneling paths, originally suggested by Makri and Miller [J. Chem. Phys. 91, 4026 (1989)] and recently implemented by Truhlar and co-workers [Chem. Sci. 5, 2091 (2014)], is tested for one- and two-dimensional ab initio based potentials describing hydrogen dissociation in the 1B1 excited electronic state of pyrrole. The primary observables are the tunneling rates in a progression of bending vibrational states lying below the dissociation barrier and their isotope dependences. Several initial ensembles of classical trajectories have been considered, corresponding to the quasiclassical and the quantum mechanical samplings of the initial conditions. It is found that the sampling based on the fixed energy Wigner density gives the best agreement with the quantum mechanical dissociation rates.

  20. Gamma irradiation effect on polymers derived of pyrrole synthesized by plasma

    International Nuclear Information System (INIS)

    This work studies the effect of gamma irradiation at doses of 50, 100, 200, 400 and 800 kGy on polymers obtained from pyrrole synthesized by plasma. The evolution of the structure was studied by Fourier transform infrared spectroscopy (Ftir) and X-ray photoelectron spectroscopy (XPS). The Ftir spectra show that poly pyrroles have N-H, C-H, C=O, triple and consecutive double bonds in their structure. The irradiated polymers show the same chemical groups in their structure without significant changes. Nevertheless, a more detailed analysis by XPS allows the identification of superficial chemical states, such as: C=CH-C, C=CC-C, C-NH-C, C-NC-C, etc., and shows that most of these states are present in all polymers but with different participation. One possible mechanism indicates that as the irradiation dose increases, dehydrogenation processes are performed increasing fragmentation, crosslinking and formation of multiple bonds. The fragmentation and thermal degradation were studied by thermogravimetric analysis, indicating that the loss of moisture and light compounds formed during gamma irradiation occurs in the firsts 100 grades C. The main degradation of all polymers occurs from 150 to 700 grades C, suggesting that the thermal stability is independent of the irradiation dose in the interval studied. Morphology was studied using scanning electron microscopy techniques. Before irradiation, the polymer presented a uniform and practically smooth surface, however, after gamma irradiation, the applied energy increased roughness and macro fragmentation. The roughness and functional groups on the surface reduced the contact angle with water as the irradiation dose increased. However, the polymers are hydrophilic, because for all doses that contact angle is smaller than 90 grades C. Electrical conductivity was calculated respect to temperature in the interval from 25 to 100 grades C. Conductivity increases with temperature and is slightly greater in the irradiated polymers

  1. Optoelectrochemical properties of the copolymer of 2,5-di(4-methylthiophen-2-yl)-1-(4-nitrophenyl)-1H-pyrrole monomer with 3,4-ethylenedioxythiophene

    Energy Technology Data Exchange (ETDEWEB)

    Ak, Metin [Department of Chemistry, Middle East Technical University, 06531, Ankara (Turkey); Department of Chemistry, Faculty of Art and Sciences, Pamukkale University, 20017 Denizli (Turkey)], E-mail: metinak@pau.edu.tr; Tanyeli, Cihangir [Department of Chemistry, Middle East Technical University, 06531, Ankara (Turkey)], E-mail: tanyeli@metu.edu.tr; Akhmedov, Idris M. [Department of Chemistry, Middle East Technical University, 06531, Ankara (Turkey)], E-mail: idrism@chem.metu.edu.tr; Toppare, Levent [Department of Chemistry, Middle East Technical University, 06531, Ankara (Turkey)], E-mail: toppare@metu.edu.tr

    2008-04-30

    Copolymer of 2,5-di(4-methylthiophen-2-yl)-1-(4-nitrophenyl)-1H-pyrrole (MTNP) with 3,4-ethylene dioxythiophene (EDOT) was electrochemically synthesized and characterized via cyclic voltammetry, Fourier Transform Infrared spectroscopy, Scanning Electron Microscopy, conductivity measurements. Spectroelectrochemical investigations showed that resulting copolymer film has distinct electrochromic properties. It has five different colors (dark purple, red, light grey, green, blue). At the neutral state {lambda}{sub max} due to the {pi}-{pi}* transition was found to be 500 nm and E{sub g} was calculated as 1.71 eV. Double potential step chronoamperometry experiment shows that copolymer film has good stability, fast switching time (1.1 s) and high optical contrast (30%). Electrochromic device based on P(MTNP-co-EDOT) and PEDOT was constructed and characterized. Oxidized state of the device shows dark purple color with a blue color reduced state. At interval potentials device has good transparency and colors of the device are yellow and grey. Maximum contrast and switching time of the device were measured as 23% and 1.1 s at 650 nm.

  2. Optoelectrochemical properties of the copolymer of 2,5-di(4-methylthiophen-2-yl)-1-(4-nitrophenyl)-1H-pyrrole monomer with 3,4-ethylenedioxythiophene

    International Nuclear Information System (INIS)

    Copolymer of 2,5-di(4-methylthiophen-2-yl)-1-(4-nitrophenyl)-1H-pyrrole (MTNP) with 3,4-ethylene dioxythiophene (EDOT) was electrochemically synthesized and characterized via cyclic voltammetry, Fourier Transform Infrared spectroscopy, Scanning Electron Microscopy, conductivity measurements. Spectroelectrochemical investigations showed that resulting copolymer film has distinct electrochromic properties. It has five different colors (dark purple, red, light grey, green, blue). At the neutral state λmax due to the π-π* transition was found to be 500 nm and Eg was calculated as 1.71 eV. Double potential step chronoamperometry experiment shows that copolymer film has good stability, fast switching time (1.1 s) and high optical contrast (30%). Electrochromic device based on P(MTNP-co-EDOT) and PEDOT was constructed and characterized. Oxidized state of the device shows dark purple color with a blue color reduced state. At interval potentials device has good transparency and colors of the device are yellow and grey. Maximum contrast and switching time of the device were measured as 23% and 1.1 s at 650 nm

  3. Zur Reaktion von Pyroglutaminsäure-Derivaten mit Phosphorpentachlorid - Darstellung chlorierter Pyrrol-2-carbonsäure-Derivate (Aminosäuren ; 9)

    OpenAIRE

    Effenberger, Franz; Müller, Wolfgang; Isak, Heinz

    1987-01-01

    N-Benzyl-5-oxoprolinester 5 werden mit PCl5 über verschiedene chlorierte Zwischenstufen zu N-Benzyl-4,5-dichlor-1H-pyrrol-2-carbonsäureestern 6 chloriert, während N-Benzhydryl- L-3 und N-Acyl-5-oxoprolinester L-4 mit PCl5 unter Abspaltung des N-Substituenten L-4,4,5-Trichlor-3,4-dihydro-2H-pyrrol-2-carbon-säureester 18 bilden, die mit Base in die 4,5-Dichlor-1H-pyrrol-2-carbonsäureester 20 übergehen. Diese Umsetzungen stellen die beste Methode zur Herstellung von 4,5-Dichlor-1H-pyrrol-2-carbo...

  4. Zn(OTf)2 promoted rearrangement of 1,2-cyclopropanated sugars with amines: a convenient method for the synthesis of 3-polyhydroxyalkyl-substituted pyrrole derivatives.

    Science.gov (United States)

    Shen, Xudong; Xia, Jianhui; Liang, Peng; Ma, Xiaofeng; Jiao, Wei; Shao, Huawu

    2015-11-28

    A rearrangement reaction of 1,2-cyclopropanated sugars with alkylamines or arylamines promoted by Zn(OTf)2 is described. The method offers a series of 3-polyhydroxyalkyl-substituted pyrrole derivatives with multiple chiral centers in moderate to excellent yields. The epimerization is achieved by inverting the stereochemistry at the free hydroxyl group of the resulting pyrrole, which would give access to many more possible stereoisomers.

  5. Strikingly different luminescent properties arising from single crystals grown from solution or from the vapor phase in a diketo-pyrrolo-pyrrole analog

    OpenAIRE

    Imoda, Tomohiko; Mizuguchi, Jin

    2007-01-01

    The title compound di-cyano-pyrrolo-pyrrole (DCPP) is an analog of diketo-pyrrolo-pyrrole (DPP) known as a red pigment on the market. Brilliant orange photoluminescence has been observed in crystals of DCPP recrystallized from solution (crystal I); whereas the luminescence was quite weak in single crystals grown from the vapor phase (crystal II). To elucidate the difference in luminescent properties, a series of structural analysis together with thermal analysis has been carried out on crysta...

  6. Green Synthesis of Ag and Pd Nanospheres, Nanowires, and Nanorods Using Vitamin B2: Catalytic Polymerisation of Aniline and Pyrrole

    Directory of Open Access Journals (Sweden)

    Mallikarjuna N. Nadagouda

    2008-01-01

    Full Text Available For the first time, we report green chemistry approach using vitamin B2 in the synthesis of silver (Ag and palladium (Pd, nanospheres, nanowires, and nanorods at room temperature without using any harmful reducing agents, such as sodium borohydride (NaBH4 or hydroxylamine hydrochloride and any special capping or dispersing agent. Vitamin B2 was used as reducing agent as well as capping agent due to its high-water solubility, biodegradability, and low-toxicity compared with other reducing agents. The average particle size of nanoprticle was found to be Ag (average size 6.1±0.1 nm and Pd (average size 4.1±0.1 nm nanoparticles in ethylene glycol and Ag (average size 5.9±0.1 nm, and average size 6.1±0.1 nanoparticles in acetic acid and NMP, respectively. The formation of noble multiple shape nanostructures and their self assembly were dependent on the solvent employed for the preparation. When water was used as solvent media, Ag and Pd nanoparticles started to self-assemble into rod-like structures and in isopropanol Ag and Pd nanoparticles yielded wire-like structures with a thickness in the range of 10 to 20 nm and several hundred microns in length. In acetone and acetonitrile medium, the Ag and Pd nanoparticles are self-assembled into a regular pattern making nanorod structures with thicknesses ranging from 100 to 200 nm and lengths of a few microns. The so-synthesized nanostructures were characterized using scanning electron microscopy (SEM, transmission electron microscopy (TEM, energy dispersive X-ray (EDX analysis, and UV spectroscopy. The ensuing Ag and Pd nanoparticles catalyzed the reactions of aniline and pyrrole to generate polyaniline and polypyrrole nanofibers and may find various technological and biological applications. This single-step greener approach is general and can be extended to other noble metals and transition metal oxides.

  7. CHANGES OF STRUCTURE AND PROPERTIES OF POLY (ETHYLENE TEREPHTHALATE)CAUSED BY IN-SITU POLYMERIZATION OF PYRROLE

    Institute of Scientific and Technical Information of China (English)

    HE Jiasong; FENG Zhihai

    1991-01-01

    Conductive polymer composites based on crystalline polymer matrix have been prepared by using an in-situ polymerization process of pyrrole in amorphous poly (ethylene terephthalate) (PET) film.The DSC and WAXD measurement and SEM observation show that liquid-induced crystallization of PET matrix has occurred during the preparation of composite films. Depending upon the equilibrium degree of swelling and crystallinity, the limited depth of penetration of pyrrole molecules results in a skin-core structure of the composite film. The skin layer containing charge transfer intercalated polypyrrole has a surface resistance of 3.5 × 104 Ω. Rigid and heat-resistant polypyrrole molecules formed in PET film increase the tensile modulus and, especially, the rigidity of PET at elevated temperatures. However, they decrease the tensile strength and elongation at break, and impair the thermal ductility of PET.

  8. Highly enantioselective synthesis of beta-heteroaryl-substituted dihydrochalcones through Friedel-Crafts alkylation of indoles and pyrrole.

    Science.gov (United States)

    Wang, Wentao; Liu, Xiaohua; Cao, Weidi; Wang, Jun; Lin, Lili; Feng, Xiaoming

    2010-02-01

    A highly enantioselective Friedel-Crafts (F-C) alkylation of indoles and pyrrole with chalcone derivatives catalyzed by a chiral N,N'-dioxide-Sc(OTf)(3) complex has been developed that tolerates a wide range of substrates. The reaction proceeds in moderate to excellent yields and high enantioselectivities (85-92 % enantiomeric excess) using 2 mol % (for indole) or 0.5 mol % (for pyrrole) catalyst loading, which showed the potential value of the catalyst system. Meanwhile, a strong positive nonlinear effect was observed. On the basis of the experimental results and previous reports, a possible working model is proposed to explain the origin of the activation and asymmetric induction. PMID:20013964

  9. Novel MWCNT-Support for Co-Mo Sulfide Catalyst in HDS of Thiophene and HDN of Pyrrole

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    With home-made multi-walled carbon nanotubes (MWCNTs, simplified as CNTs in later text) as support, CNT-supported Co-Mo-S catalysts, denoted as x%(mass percentage)MoiCoj/CNTs,were prepared. Their catalytic performance for thiophene hydrodesulfurization (HDS) and pyrrole hydrodenitrification (HDN) reactions was studied, and compared with the reference system supported by AC. Over the 7.24%Mo3Co1/CNTs catalyst at reaction condition of 1.5 MPa, 613 K,C4H4S/H2 =3.7/96.3(molar ratio) and GHSV≈8000 mlSTP/(g-cat.h), the specific HDS activity of thiophene the AC-based counterpart, and was 2.47 times as high as that (1.33 mmolC4H4S/(s.molMo)) of the catalysts supported by AC with the respective optimal Mo3Co1-loading amount, 16.90%Mo3Co1/AC. Analogous reaction-chemical behaviours were also observed in the case of pyrrole HDN. It was experimentally found that using the CNTs in place of AC as support of the catalyst caused little change in the apparent activation energy for the thiophene HDS or pyrrole HDN reaction, but led to a significant increase in the concentration of catalytically active Mo-species (Mo4+) at the surface of the functioning catalyst. On the other hand, H2-TPD measurements revealed that the CNT-supported catalyst could reversibly adsorb a greater amount of hydrogen under atmospheric pressure at temperatures ranging from room temperature to about 673 K. This unique feature would help to generate microenvironments with higher stationarystate concentration of active hydrogen-adspecies at the surface of the functioning catalyst. Both factors mentioned above were favorable to increasing the rate of thiophene HDS and pyrrole HDN reactions.

  10. N-Heterocyclic carbene–palladium catalysts for the direct arylation of pyrrole derivatives with aryl chlorides

    Directory of Open Access Journals (Sweden)

    Ismail Özdemir

    2013-02-01

    Full Text Available New Pd–NHC complexes have been synthesized and employed for palladium-catalyzed direct arylation of pyrrole derivatives by using electron-deficient aryl chlorides as coupling partners. The desired coupling products were obtained in moderate to good yields by using 1 mol % of these air-stable palladium complexes. This is an advantage compared to the procedures employing air-sensitive phosphines, which have been previously shown to promote the coupling of aryl chlorides with heteroarenes.

  11. Direct detection of pyridine formation by the reaction of CH (CD) with pyrrole: a ring expansion reaction

    Energy Technology Data Exchange (ETDEWEB)

    Soorkia, Satchin; Taatjes, Craig A.; Osborn, David L.; Selby, Talitha M.; Trevitt, Adam J.; Wilson, Kevin R.; Leone, Stephen R.

    2010-03-16

    The reaction of the ground state methylidyne radical CH (X2Pi) with pyrrole (C4H5N) has been studied in a slow flow tube reactor using Multiplexed Photoionization Mass Spectrometry coupled to quasi-continuous tunable VUV synchrotron radiation at room temperature (295 K) and 90 oC (363 K), at 4 Torr (533 Pa). Laser photolysis of bromoform (CHBr3) at 248 nm (KrF excimer laser) is used to produce CH radicals that are free to react with pyrrole molecules in the gaseous mixture. A signal at m/z = 79 (C5H5N) is identified as the product of the reaction and resolved from 79Br atoms, and the result is consistent with CH addition to pyrrole followed by Helimination. The Photoionization Efficiency curve unambiguously identifies m/z = 79 as pyridine. With deuterated methylidyne radicals (CD), the product mass peak is shifted by +1 mass unit, consistent with the formation of C5H4DN and identified as deuterated pyridine (dpyridine). Within detection limits, there is no evidence that the addition intermediate complex undergoes hydrogen scrambling. The results are consistent with a reaction mechanism that proceeds via the direct CH (CD) cycloaddition or insertion into the five-member pyrrole ring, giving rise to ring expansion, followed by H atom elimination from the nitrogen atom in the intermediate to form the resonance stabilized pyridine (d-pyridine) molecule. Implications to interstellar chemistry and planetary atmospheres, in particular Titan, as well as in gas-phase combustion processes, are discussed.

  12. Copper-Catalyzed Coupling of 2-Siloxy-1-alkenes and Diazocarbonyl Compounds: Approach to Multisubstituted Furans, Pyrroles, and Thiophenes.

    Science.gov (United States)

    Tan, Wei Wen; Yoshikai, Naohiko

    2016-07-01

    We report herein copper(II)-catalyzed cyclization reactions of silyl enol ethers derived from methyl ketones with α-diazo-β-ketoesters or α-diazoketones to afford 2-siloxy-2,3-dihydrofuran derivatives or 2,3,5-trisubstituted furans, respectively, under mild conditions. The former cyclization products serve as versatile 1,4-diketone surrogates, allowing facile preparation of 2,3,5-trisubstituted furans, pyrroles, and thiophenes. PMID:27259097

  13. Pyrrole PMOs, incorporating new N-heterocyclic compounds on an ethene-PMO through Diels–Alder reactions

    Energy Technology Data Exchange (ETDEWEB)

    Esquivel, Dolores; De Canck, Els [Center for Ordered Materials, Organometallics and Catalysis, Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281-S3, 9000 Ghent (Belgium); Jiménez-Sanchidrián, César [Department of Organic Chemistry, Nanochemistry and Fine Chemistry Research Institute (IUIQFN), Faculty of Sciences, University of Córdoba, Campus de Rabanales, Marie Curie Building, Ctra. Nnal. IV, km 396, 14071 Córdoba (Spain); Romero-Salguero, Francisco J., E-mail: qo2rosaf@uco.es [Department of Organic Chemistry, Nanochemistry and Fine Chemistry Research Institute (IUIQFN), Faculty of Sciences, University of Córdoba, Campus de Rabanales, Marie Curie Building, Ctra. Nnal. IV, km 396, 14071 Córdoba (Spain); Van Der Voort, Pascal, E-mail: pascal.vandervoort@ugent.be [Center for Ordered Materials, Organometallics and Catalysis, Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281-S3, 9000 Ghent (Belgium)

    2014-11-14

    The ethenylene bridges on the walls of an ethenylene-bridged periodic mesoporous organosilica were successfully modified with a variety of pyrrole derivatives – pyrrole, methylpyrrole, dimethylpyrrole, trimethylpyrrole and 1-phenylpyrrole – through Diels–Alder reactions. X-ray diffraction measurements and N{sub 2} adsorption–desorption analysis confirmed the preservation of the ordering and mesoporosity of the parent material as well as the decoration of the pores with the surface Diels–Alder adducts. Moreover, other techniques such as DRIFT, {sup 13}C and {sup 29}Si nuclear magnetic resonances revealed the formation of the surface N-heterocyclic compounds at the parent ethenylene sites. - Highlights: • Chemical modification of the double bonds on an ethene-PMO through the Diels–Alder reaction. • A family of pyrrole derivatives act as dienes in the Diels–Alder reaction. • Well-ordering and mesoporosity are retained after the post-functionalization. • N-containing compounds on the surface of ethene-PMO are present after the Diels–Alder reaction.

  14. Pyrrole PMOs, incorporating new N-heterocyclic compounds on an ethene-PMO through Diels–Alder reactions

    International Nuclear Information System (INIS)

    The ethenylene bridges on the walls of an ethenylene-bridged periodic mesoporous organosilica were successfully modified with a variety of pyrrole derivatives – pyrrole, methylpyrrole, dimethylpyrrole, trimethylpyrrole and 1-phenylpyrrole – through Diels–Alder reactions. X-ray diffraction measurements and N2 adsorption–desorption analysis confirmed the preservation of the ordering and mesoporosity of the parent material as well as the decoration of the pores with the surface Diels–Alder adducts. Moreover, other techniques such as DRIFT, 13C and 29Si nuclear magnetic resonances revealed the formation of the surface N-heterocyclic compounds at the parent ethenylene sites. - Highlights: • Chemical modification of the double bonds on an ethene-PMO through the Diels–Alder reaction. • A family of pyrrole derivatives act as dienes in the Diels–Alder reaction. • Well-ordering and mesoporosity are retained after the post-functionalization. • N-containing compounds on the surface of ethene-PMO are present after the Diels–Alder reaction

  15. Aggregation behavior and electrical properties of amphiphilic pyrrole-tailed ionic liquids in water, from the viewpoint of dielectric relaxation spectroscopy.

    Science.gov (United States)

    Fan, Xiaoqing; Zhao, Kongshuang

    2014-05-14

    The self-aggregation behavior of amphiphilic pyrrole-tailed imidazolium ionic liquids (Py(CH₂)₁₂mim⁺Br⁻: Py = pyrrole, mim = methylimidazolium) in water is investigated by dielectric spectroscopy from 40 Hz to 110 MHz. Dielectric determination shows that the critical micelle concentration (CMC) is 8.5 mM, which is lower than that for traditional ionic surfactants. The thermodynamic parameter of the micellization, the Gibbs free energy ΔG, was calculated for Py(CH₂)₁₂mim⁺Br⁻ and compared to those of the corresponding C(n)mim⁺Br⁻ (n = 12, 14). It was found that the main driven forces of the Py(CH₂)₁₂mim⁺Br⁻ aggregation were hydrophobic interaction and π-π interactions among the adjacent Py groups. Further, the structure of aggregation was speculated theoretically that Py groups partially insert into the alkyl chains and the staggered arrangement in micelles is formed. When the concentration of Py(CH₂)₁₂mim⁺Br⁻ is higher than CMC, two remarkable relaxations which originated from diffusion of counterions and interfacial polarization between the micelles and solution, were observed at about 1.3 MHz and 55 MHz. The relaxation parameters representing the real properties of the whole system were obtained by fitting the experimental data with Cole-Cole equation. A dielectric model characterizing the structure and electrical properties of spherical micelles was proposed by which the conductivity, permittivity and the volume fraction of micelles as well as electrical properties of solution were calculated from the relaxation parameters. An intriguingly high permittivity of about 150 for the micelle was found to be a direct consequence of the strong orientational order of water molecules inside the core of micelle, and essentially is attributed to the special structure of the micelle. Furthermore, the calculation of the interfacial electrokinetic parameters of the micelles, i.e., the surface conductivity, surface charge density

  16. Synthesis, molecular structure and spectral analysis of ethyl 4-formyl-3,5-dimethyl-1H-pyrrole-2-carboxylate thiosemicarbazone: A combined DFT and AIM approach

    Science.gov (United States)

    Singh, R. N.; Kumar, Amit; Tiwari, R. K.; Rawat, Poonam; Verma, Divya; Baboo, Vikas

    2012-05-01

    A new ethyl 4-formyl-3,5-dimethyl-1H-pyrrole-2-carboxylate thiosemicarbazone (EFDMPCT) has been synthesized and characterized by elemental analysis and FT-IR, 1H NMR, UV-Visible, DART-mass spectroscopy. Quantum chemical calculations have been performed by DFT level of theory using B3LYP functional and 6-31G (d,p) as basis set. The calculated 1H NMR chemical shifts using gauge including atomic orbitals (GIAO) approach are in good agreement with the observed chemical shifts. The electronic transitions within molecule have been interpreted using the time dependent density functional theory (TD-DFT). The calculated and experimental wavenumbers analyses confirm the existence of dimer. Topological parameters electron density, Laplacian of electron density, kinetic electron energy density, potential electron density and the total electron energy density at the bond critical points (BCP) analyzed using 'Atoms in Molecules' AIM theory reveals intra and inter molecular hydrogen bonding other weaker interactions in detail. The calculated intermolecular hydrogen bond energy of dimer is -12.2176 kcal/mol using AIM calculation. The results of AIM ellipticity confirm the existence of resonance assisted hydrogen bonds in dimer. The calculated thermodynamic parameters show that reaction is exothermic and non-spontaneous at room temperature. The local reactivity descriptors find the reactive sites within molecules have been calculated.

  17. Synthesis, cytotoxic activity, and tubulin polymerization inhibitory activity of new pyrrol-2(3H)-ones and pyridazin-3(2H)-ones.

    Science.gov (United States)

    Abbas, Samar Hafez; Abuo-Rahma, Gamal El-Din A A; Abdel-Aziz, Mohamed; Aly, Omar M; Beshr, Eman A; Gamal-Eldeen, Amira M

    2016-06-01

    A series of new pyrrol-2(3H)-ones 4a-f and pyridazin-3(2H)-ones 7a-f were synthesized and characterized using different spectroscopic tools. Some of the tested compounds revealed moderate activity against 60 cell lines. The E form of the pyrrolones 4 showed good cytotoxic activity than both the Z form and the corresponding open amide form. Furthermore, the in vitro cytotoxic activity against HepG2 and MCF-7 cell lines revealed that compounds (E)4b, 6f and 7f showed good cytotoxic activity against HepG2 with IC50 values of 11.47, 7.11 and 14.80μM, respectively. Compounds (E)4b, 6f, 7d and 7f showed a pronounced inhibitory effect against cellular localization of tubulin. Flow cytometric analysis indicated that HepG2 cells treated with (E)4b showed a predominated growth arrest at the S-phase compared to that of G2/M-phase. Molecular modeling study using MOE® program indicated that most of the target compounds showed good binding of β-subunit of tubulin with the binding free energy (dG) values about -10kcal/mole.

  18. Electrochromic properties of poly (1-(phenyl)-2,5-di(2-thienyl)-1H-pyrrole-co-3,4-ethylenedioxy thiophene) and its application in electrochromic devices

    Science.gov (United States)

    Tarkuc, S.; Sahmetlioglu, E.; Tanyeli, C.; Akhmedov, I. M.; Toppare, L.

    2008-06-01

    Electrochemical copolymerization of 1-(phenyl)-2,5-di(2-thienyl)-1H-pyrrole (PTP) with 3,4-ethylenedioxy thiophene (EDOT) was carried out in acetonitrile (AN)/NaClO4/LiClO4 (0.1 M) solvent-electrolyte couple via potentiodynamic electrolysis. Characterizations of the resulting copolymer were performed via cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and spectroelectrochemical analysis. Spectroelectrochemical analyses show that the copolymer of PTP with EDOT has an electronic band gap (due to π to π∗ transition) of 1.9 eV at 480 nm, with a claret red in the fully reduced form and a blue color in the fully oxidized form. Via kinetic studies, the optical contrast (ΔT %) was found to be 8% for P(PTP-co-EDOT). Results showed that the time required to reach 95% of the ultimate transmittance was 1.7 s for the copolymer. The P(PTP-co-EDOT) film was used to construct a dual type polymer electrochromic device (ECDs) with poly(3,4-ethylenedioxy thiophene) (PEDOT). Spectroelectrochemistry, electrochromic switching and open circuit memory of the device were investigated.

  19. A concise synthesis of (+)-batzelladine B from simple pyrrole-based starting materials

    Science.gov (United States)

    Parr, Brendan T.; Economou, Christos; Herzon, Seth B.

    2015-09-01

    Alkaloids, secondary metabolites that contain basic nitrogen atoms, are some of the most well-known biologically active natural products in chemistry and medicine. Although efficient laboratory synthesis of alkaloids would enable the study and optimization of their biological properties, their preparation is often complicated by the basicity and nucleophilicity of nitrogen, its susceptibility to oxidation, and its ability to alter reaction outcomes in unexpected ways--for example, through stereochemical instability and neighbouring group participation. Efforts to address these issues have led to the invention of a large number of protecting groups that temper the reactivity of nitrogen; however, the use of protecting groups typically introduces additional steps and obstacles into the synthetic route. Alternatively, the use of aromatic nitrogen heterocycles as synthetic precursors can attenuate the reactivity of nitrogen and streamline synthetic strategies. Here we use such an approach to achieve a synthesis of the complex anti-HIV alkaloid (+)-batzelladine B in nine steps (longest linear sequence) from simple pyrrole-based starting materials. The route uses several key transformations that would be challenging or impossible to implement using saturated nitrogen heterocycles and highlights some of the advantages of beginning with aromatic reagents.

  20. Palladium complexes of pyrrole-2-aldehyde thiosemicarbazone: Synthesis, structure and spectral properties

    Indian Academy of Sciences (India)

    Piyali Paul; Samaresh Bhattacharya

    2014-09-01

    Reaction of pyrrole-2-aldehyde thiosemicarbazone (abbreviated as H2L, where H2 stands for the two potentially dissociable protons) with [Pd(PPh3)2Cl2] in ethanol in the presence of NEt3 afforded two complexes, [Pd(PPh3)(HLNS)Cl] and [Pd(PPh3)(LNNS)], where the thiosemicarbazone ligand is coordinated to the metal centre respectively as monoanionic N,S-donor (depicted by HLNS) and dianionic N,N,S-donor (depicted by LNNS). Similar reaction with Na2[PdCl4] afforded a bis-complex, [Pd(HLNS)2]. Crystal structures of all the three complexes have been determined.With reference to the structure of the uncoordinated thiosemicarbazone (H2L), the N,S-coordinationmode observed in [Pd(PPh3)(HLNS)Cl] and [Pd(HLNS)2] is associated with a geometrical change around the imine bond.While the N,N,S-mode of binding observed in [Pd(PPh3)(LNNS)] takes place without any such geometrical change. All three complexes display intense absorptions in the visible and ultraviolet regions, which have been analyzed by TDDFT method.

  1. Experimental and computational thermochemistry of 1-phenylpyrrole and 1-(4-methylphenyl)pyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Ana Filipa L.O.M. [Centro de Investigacao em Quimica, Department of Chemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal); Ribeiro da Silva, Manuel A.V., E-mail: risilva@fc.up.p [Centro de Investigacao em Quimica, Department of Chemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, 687, P-4169-007 Porto (Portugal)

    2010-06-15

    The standard (p{sup o} = 0.1 MPa) molar enthalpies of formation, in the crystalline phase, of 1-phenylpyrrole and 1-(4-methylphenyl)pyrrole, at T = 298.15 K, were derived from the standard molar energies of combustion in oxygen, measured by static-bomb combustion calorimetry. For these compounds, the standard molar enthalpies of sublimation, at T = 298.15 K, were determined from the temperature-vapour pressure dependence, obtained by the Knudsen mass-loss effusion method. Using estimated values for the heat capacity differences between the gas and the crystal phases of the studied compounds, the standard (p{sup o} = 0.1 MPa) molar enthalpies, entropies, and Gibbs energies of sublimation, at T = 298.15 K, were derived. From the experimental values, the standard molar enthalpies of formation, in the gaseous phase, at T = 298.15 K, were calculated. Additionally, the enthalpies of formation of both compounds were estimated using the composite G3(MP2)//B3LYP approach together with adequate gas-phase working reactions. There is a very good agreement between computational and experimental results.

  2. Crystal structures of unsymmetrically mixed β-pyrrole substituted nickel(II)-meso-tetraphenylporphyrins

    Indian Academy of Sciences (India)

    BHYRAPPA PUTTAIAH; VELKANNAN VEERAPANDIAN; SARANGI UJWAL KUMAR

    2016-07-01

    Crystal structures of solvated unsymmetrically substituted meso-tetraphenylporphyrins, 2,3,12,13, 17-pentachloro-5,7,8,10,15,18,20-hepta-phenylporphyrin, H₂TPP(Ph)₃(Cl)₅, 1 and its nickel(II), NiTPP(Ph)₃(Cl)₅, 2 were determined by single crystal XRD analysis. In addition, a new unsymmetricallysubstituted porphyrin, 2,3,12,13,17-pentacyano-5,7,8,10,15,18,20-heptaphenyl-porphinato nickel(II) complex, NiTPP(Ph)₃(CN)₅, 3 complex was synthesized and its solvated structure was examined by crystallography. These porphyrins exhibited dramatic nonplanar conformation of the macrocycle as evidenced from the averagedisplacement of the β-pyrrole carbon (±ΔCβ ) from the mean plane of the porphyrin ring and the trend in nonplanarity varies in the order: 2 (1.189(5) Å) > 1 (1.036(6) Å) > 3 (0.895(6) Å). The normal-coordinate structural decomposition analysis of these structures revealed mainly saddle distortion of the macrocycle combined with small degree of ruffled or domed distortions. The Hirshfeld surface analysis of structures 1-3 revealed solvate dependent intermolecular contacts with varying degree of H. . .H (43–49%), C. . .H (17–19%), H. . .Cl (25–30%) and N. . .H (~19%) contact contributions.

  3. Efficient Synthesis of Peptide and Protein Functionalized Pyrrole-Imidazole Polyamides Using Native Chemical Ligation.

    Science.gov (United States)

    Janssen, Brian M G; van Ommeren, Sven P F I; Merkx, Maarten

    2015-06-04

    The advancement of DNA-based bionanotechnology requires efficient strategies to functionalize DNA nanostructures in a specific manner with other biomolecules, most importantly peptides and proteins. Common DNA-functionalization methods rely on laborious and covalent conjugation between DNA and proteins or peptides. Pyrrole-imidazole (Py-Im) polyamides, based on natural minor groove DNA-binding small molecules, can bind to DNA in a sequence specific fashion. In this study, we explore the use of Py-Im polyamides for addressing proteins and peptides to DNA in a sequence specific and non-covalent manner. A generic synthetic approach based on native chemical ligation was established that allows efficient conjugation of both peptides and recombinant proteins to Py-Im polyamides. The effect of Py-Im polyamide conjugation on DNA binding was investigated by Surface Plasmon Resonance (SPR). Although the synthesis of different protein-Py-Im-polyamide conjugates was successful, attenuation of DNA affinity was observed, in particular for the protein-Py-Im-polyamide conjugates. The practical use of protein-Py-Im-polyamide conjugates for addressing DNA structures in an orthogonal but non-covalent manner, therefore, remains to be established.

  4. Efficient Synthesis of Peptide and Protein Functionalized Pyrrole-Imidazole Polyamides Using Native Chemical Ligation

    Directory of Open Access Journals (Sweden)

    Brian M. G. Janssen

    2015-06-01

    Full Text Available The advancement of DNA-based bionanotechnology requires efficient strategies to functionalize DNA nanostructures in a specific manner with other biomolecules, most importantly peptides and proteins. Common DNA-functionalization methods rely on laborious and covalent conjugation between DNA and proteins or peptides. Pyrrole-imidazole (Py–Im polyamides, based on natural minor groove DNA-binding small molecules, can bind to DNA in a sequence specific fashion. In this study, we explore the use of Py–Im polyamides for addressing proteins and peptides to DNA in a sequence specific and non-covalent manner. A generic synthetic approach based on native chemical ligation was established that allows efficient conjugation of both peptides and recombinant proteins to Py–Im polyamides. The effect of Py–Im polyamide conjugation on DNA binding was investigated by Surface Plasmon Resonance (SPR. Although the synthesis of different protein-Py–Im-polyamide conjugates was successful, attenuation of DNA affinity was observed, in particular for the protein-Py–Im-polyamide conjugates. The practical use of protein-Py–Im-polyamide conjugates for addressing DNA structures in an orthogonal but non-covalent manner, therefore, remains to be established.

  5. Synthetic, enzyme kinetic, and protein crystallographic studies of C-β-d-glucopyranosyl pyrroles and imidazoles reveal and explain low nanomolar inhibition of human liver glycogen phosphorylase.

    Science.gov (United States)

    Kantsadi, Anastassia L; Bokor, Éva; Kun, Sándor; Stravodimos, George A; Chatzileontiadou, Demetra S M; Leonidas, Demetres D; Juhász-Tóth, Éva; Szakács, Andrea; Batta, Gyula; Docsa, Tibor; Gergely, Pál; Somsák, László

    2016-11-10

    C-β-d-Glucopyranosyl pyrrole derivatives were prepared in the reactions of pyrrole, 2-, and 3-aryl-pyrroles with O-peracetylated β-d-glucopyranosyl trichloroacetimidate, while 2-(β-d-glucopyranosyl) indole was obtained by a cross coupling of O-perbenzylated β-d-glucopyranosyl acetylene with N-tosyl-2-iodoaniline followed by spontaneous ring closure. An improved synthesis of O-perbenzoylated 2-(β-d-glucopyranosyl) imidazoles was achieved by reacting C-glucopyranosyl formimidates with α-aminoketones. The deprotected compounds were assayed with isoforms of glycogen phosphorylase (GP) to show no activity of the pyrroles against rabbit muscle GPb. The imidazoles proved to be the best known glucose derived inhibitors of not only the muscle enzymes (both a and b) but also of the pharmacologically relevant human liver GPa (Ki = 156 and 26 nM for the 4(5)-phenyl and -(2-naphthyl) derivatives, respectively). An X-ray crystallographic study of the rmGPb-imidazole complexes revealed structural features of the strong binding, and also allowed to explain the absence of inhibition for the pyrrole derivatives. PMID:27522507

  6. Morphological and physicochemical properties of dip-coated poly {(2,5-diyl pyrrole) [4-nitrobenzylidène]} (PPNB) thin films: towards photovoltaic applications

    Science.gov (United States)

    Mouchaal, Younes; Gherrass, Hamou; Bendoukha Reguig, Abdelkarim; Hachemaoui, Aïcha; Yahiaoui, Ahmed; Makha, Mohamed; Khelil, Abdelbacet; Bernede, Jean-Christian

    2015-02-01

    A new material: conjugated poly {(2,5-diyl pyrrole) [4-nitrobenzylidène]}, that we called (PPNB), has been synthesized and characterized. The cyclic voltammetry has been used in order to estimate first oxidation (Ep) and reduction (En) potentials of our polymer. These values have been assigned, respectively, to the position of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) and determination of the energy band gap which have been estimated to be 6.16, 3.89 and 2.27 eV respectively. Energy levels values of the HOMO and LUMO of the PPNB polymeric donor material were evaluated and the results are compatible with an electron transfer to C60 within an eventual junction, such values show that PPNB could be probed for applications in organic solar cells as donor material. PPNB Thin films have been deposited by dip-coating technique from Dichloromethane solvent with different polymer concentrations, and a dipping speed of 3.0 cm/min. For morphological characterization of the films scanning electron microscopy (SEM) was carried out. The samples, when observed by SEM, reveals that the films deposited are less dense, uniform. Cross-sectional SEM micrographs PPNB films show that thickness of the layers is homogeneous and has value of 35-40 nm. Optical characteristics of the polymer thin films were studied using UV-vis spectroscopy; absorption of wide range of wavelengths from 350 to 700 nm was observed. The optical band gap energy ranges between 1.9 eV and 1.94 eV. Based on these analyzes we realized heterojunction organic solar cells with the structure: ITO/Au/PPNB/C60/BCP/Al, the cells had a photovoltaique effect after J-V measuring, however the efficiency of photo generation under AM1.5 illumination was weak (about 0.02%) and needs to be improved.

  7. Synthesis and electrochemical properties of novel, donor–acceptor pyrrole derivatives with 1,8-naphthalimide units and their polymers

    International Nuclear Information System (INIS)

    A new class of bipolar monomers with pyrrole or thiophene–pyrrole–thiophene as electron donor and 1,8-naphthalimide as electron acceptor unit is reported. Donor–acceptor conjugated polymers were generated electrochemically. The synthesis of monomers, optical, electrochemical and spectroelectrochemical properties supported by theoretical calculations are presented. 1,8-naphthalimide units were attached directly to pyrrole in compounds 1a and 2a or by different bridges in the case of 1b and 2b. Intra-molecular donor–acceptor interactions of the monomers and its polymers were investigated using cyclic voltammetry, in-situ UV–Vis-NIR, electron spin resonance (ESR) spectroelectrochemistry and fluorescence spectroscopy. Studied compounds present large discrepancy (up to 1.31 eV for 2a) between energy gap values determined through electrochemical and optical measurements. The Time-dependent density functional theory (TDDFT) calculations help to explain this discrepancy. This is caused by weak HOMO to LUMO transition, 2000 times weaker than HOMO−2 to LUMO or HOMO to LUMO+1 transition. Altering the structure of monomers yields different stability and properties of obtained polymers. The p- and n-doping processes are separated. Anions are localized mainly on 1,8-naphthalimide units. Cations are localized mainly on pyrrole or thiophene–pyrrole–thiophene moiety and their polymer chains. Attachment of the additional thiophene units decreases the oxidation potential of the monomer and reduces the influence of the steric hindrance between 1,8-naphthalimide moiety and polymer/oligomers chain. This new class of model compounds is promising for use as a material with enhanced charge separation for wide range of optoelectronic, electrochromic and photovoltaic applications

  8. A Hydrogen Peroxide Sensor Prepared by Electropolymerization of Pyrrole Based on Screen-Printed Carbon Paste Electrodes

    Directory of Open Access Journals (Sweden)

    Hui Xu

    2007-03-01

    Full Text Available A disposable amperometric biosensor for commercial use to detect hydrogenperoxide has been developed. The sensor is based on screen-printed carbon paste electrodesmodified by electropolymerization of pyrrole with horseradish peroxidase (HRP entrapped.The facture techniques of fabricating the enzyme electrodes are suitable for mass productionand quality control. The biosensor shows a linear amperometric response to H2O2 from 0.1to 2.0 mM, with a sensitivity of 33.24 μA mM-1 cm-2. Different operational parameters ofelectropolymerization are evaluated and optimized.

  9. Electropolymerization of pyrrole: effects of pH and anions on the conductivity and growth kinetics of polypyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Kupila, E.L. (Dept. of Chemistry, Univ. of Turku (Finland)); Kankare, J. (Dept. of Chemistry, Univ. of Turku (Finland))

    1993-03-22

    Polypyrrole is one of the most studied conducting polymers. In situ AC conductimetry during electropolymerization is a method which allows the specific conductivity to be estimated for the polymer in statu nascendi. We have applied this method to the electropolymerization of pyrrole in aqueous solutions at various conditions. Polymers synthesized at lower pH range are of better quality than those synthesized at higher pH values. The use of small anions in the supporting electrolyte results in a layer of low conductivity at pH 7. The use of long-chain organic anions like sodium dodecylsulfate gives a high quality polymer even in neutral unbuffered solutions. (orig.)

  10. Ru-Catalysed C–H Arylation of Indoles and Pyrroles with Boronic Acids: Scope and Mechanistic Studies

    Science.gov (United States)

    Sollert, Carina; Devaraj, Karthik; Orthaber, Andreas; Gates, Paul J; Pilarski, Lukasz T

    2015-01-01

    The Ru-catalysed C2–H arylation of indoles and pyrroles by using boronic acids under oxidative conditions is reported. This reaction can be applied to tryptophan derivatives and tolerates a wide range of functional groups on both coupling partners, including bromides and iodides, which can be further derivatised selectively. New indole-based ruthenacyclic complexes are described and investigated as possible intermediates in the reaction. Mechanistic studies suggest the on-cycle intermediates do not possess a para-cymene ligand and that the on-cycle metalation occurs through an electrophilic attack by the Ru centre. PMID:25689052

  11. Synthesis and Crystal Structure of N-(1'-H-Pyrrol-2'-ylcarbonyl)-5-amino-1,10-phenanthroline

    Institute of Scientific and Technical Information of China (English)

    WANG Yue-Hong; LIN Hai; LIN Hua-Kuan

    2008-01-01

    The title compound,N-(1'-H-pyrrol-2'-ylcarbonyl)-5-amino-1,10-phenanthroline,was synthesized by the reaction of a-pyrrolyl carbonyl chloride and 5-amino-1,10-phenanthroline in pyridine.Determined by X-ray structure analysis,it crystallizes in triclinic system,space group P(1)with the following crystallographic data:C20H21N5O3,Mr=379.42,a=7.8559(4),b=9.1681(6),c =14.6818(9)(A),α=73.254(10),β=88.938(15),γ=68.080(10)°,V=934.66(10)(A)3,Z=2,F(000)=400.Dc=1.348 g/cm3 and μ=0.094 mm-1.The final R=0.0680 and wR=0.1419 for 2142observed reflections with I>2σ(I),and R=0.1084 and wR=0.1643 for all reflections.Two aromatic ring planes(pyrrole and phenanthroline rings)are connected by the amide plane.Two title complex molecules are connected through hydrogen bonds and weak π-π stacking interactions to generate a 3-D supramolecule.

  12. Rhodium and iridium complexes of N-(2'-hydroxyphenyl)pyrrole-2-aldimine: Synthesis, structure, and spectral and electrochemical properties

    Indian Academy of Sciences (India)

    Semanti Basu; Indrani Pal; Ray J Butcher; Georgina Rosair; Samaresh Bhattacharya

    2005-03-01

    Reaction of N-(2'-hydroxyphenyl)pyrrole-2-aldimine (H2L) with [M(PPh3)3Cl] (M = Rh, Ir) affords complexes of type [M(PPh3)2(L)Cl]. Structures of both complexes have been determined by X-ray crystallography. In both complexes, the N-(2'-hydroxyphenyl)pyrrole-2-aldimine ligand is coordinated to the metal centre, via dissociation of the acidic protons, as a dianionic tridentate N,N,O-donor. The M(L)Cl fragment constitutes an equatorial plane with the metal at the centre and the two PPh3 ligands occupying axial positions. The complexes are diamagnetic (low-spin 6, = 0) and show intense MLCT transitions in the visible region. Cyclic voltammetry of the [M(PPh3)2(L)Cl] complexes shows reversible M(III)-M(IV) oxidation near 0.5 V vs SCE and quasi-reversible ligand-centred oxidative response near 1.0 V vs SCE.

  13. Radiosynthesis and in vivo evaluation of [11C]-labelled pyrrole-2-carboxamide derivates as novel radioligands for PET imaging of monoamine oxidase A

    International Nuclear Information System (INIS)

    Introduction: Since MAO-A is an enzyme involved in the metabolism of neurotransmitters, fluctuations in MAO-A functionality are associated with psychiatric and neurological disorders as well as with tobacco addiction and behaviour. This study reports the radiolabelling of two [11C]-labelled pyrrole-2-carboxamide derivates, RS 2315 and RS 2360, along with the characterization of their in vivo properties. Methods: The radiolabelling of [11C]-RS 2315 and [11C]-RS 2360 was accomplished by alkylation of their amide precursors with [11C]CH3I. Biodistribution, blocking and metabolite studies of both tracers were performed in NMRI mice. Finally, a PET study in Sprague-Dawley rats was performed for [11C]-RS 2360. Results: Both tracers were obtained in a radiochemical yield of approximately 30% with radiochemical purity of >98%. Biodistribution studies showed high brain uptake followed by rapid brain clearance for both radiotracers. In the brain, [11C]-RS 2360 was more stable than [11C]-RS 2315. Blocking studies in mice could not demonstrate specificity of [11C]-RS 2315 towards MAO-A or MAO-B. The blocking and imaging study with [11C]-RS 2360 on the other hand indicated specific binding in MAO-A at the earliest time points. Conclusions: [11C]-RS 2315 displayed a high nonspecific binding and is therefore not suitable for visualization of MAO-A in vivo. [11C]-RS 2360 on the other hand has potential for mapping MAO-A since specific binding is demonstrated.

  14. Radiosynthesis and in vivo evaluation of [{sup 11}C]-labelled pyrrole-2-carboxamide derivates as novel radioligands for PET imaging of monoamine oxidase A

    Energy Technology Data Exchange (ETDEWEB)

    De Bruyne, Sylvie [Laboratory for Radiopharmacy, Ghent University, 9000 Ghent (Belgium); La Regina, Giuseppe [Istituto Pasteur, Fondazione Cenci Bolognetti, Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Universita di Roma, I-00185 Rome (Italy); Staelens, Steven [IBITECH-Medisip, Ghent University-IBBT, 9000 Ghent (Belgium); Wyffels, Leonie [Laboratory for Radiopharmacy, Ghent University, 9000 Ghent (Belgium); Deleye, Steven [IBITECH-Medisip, Ghent University-IBBT, 9000 Ghent (Belgium); Silvestri, Romano [Istituto Pasteur, Fondazione Cenci Bolognetti, Dipartimento di Chimica e Tecnologie del Farmaco, Sapienza Universita di Roma, I-00185 Rome (Italy); De Vos, Filip [Laboratory for Radiopharmacy, Ghent University, 9000 Ghent (Belgium)], E-mail: filipx.devos@ugent.be

    2010-05-15

    Introduction: Since MAO-A is an enzyme involved in the metabolism of neurotransmitters, fluctuations in MAO-A functionality are associated with psychiatric and neurological disorders as well as with tobacco addiction and behaviour. This study reports the radiolabelling of two [{sup 11}C]-labelled pyrrole-2-carboxamide derivates, RS 2315 and RS 2360, along with the characterization of their in vivo properties. Methods: The radiolabelling of [{sup 11}C]-RS 2315 and [{sup 11}C]-RS 2360 was accomplished by alkylation of their amide precursors with [{sup 11}C]CH{sub 3}I. Biodistribution, blocking and metabolite studies of both tracers were performed in NMRI mice. Finally, a PET study in Sprague-Dawley rats was performed for [{sup 11}C]-RS 2360. Results: Both tracers were obtained in a radiochemical yield of approximately 30% with radiochemical purity of >98%. Biodistribution studies showed high brain uptake followed by rapid brain clearance for both radiotracers. In the brain, [{sup 11}C]-RS 2360 was more stable than [{sup 11}C]-RS 2315. Blocking studies in mice could not demonstrate specificity of [{sup 11}C]-RS 2315 towards MAO-A or MAO-B. The blocking and imaging study with [{sup 11}C]-RS 2360 on the other hand indicated specific binding in MAO-A at the earliest time points. Conclusions: [{sup 11}C]-RS 2315 displayed a high nonspecific binding and is therefore not suitable for visualization of MAO-A in vivo. [{sup 11}C]-RS 2360 on the other hand has potential for mapping MAO-A since specific binding is demonstrated.

  15. A Highly Efficient Synthesis of 3H-(Pyrrol-1-yl)indolin-2-ones Catalyzed by InCl3

    Institute of Scientific and Technical Information of China (English)

    SHEN,Shu-Su; JI,Shun-Jun; WANG,Shun-Yi

    2008-01-01

    A systemic and comprehensive study has been made on the formation of 3H-(pyrrol-1-yl)indolin-2-ones synthesized from various isatin derivatives and 4-hydroxyproline catalyzed by InCl3 under a refluxing condition in excellent yields (83%-99%) and purity.

  16. Regioselective Preparation of Diethyl 3,4-Disubstituted 1,5-Dihydro-5-oxo-2H-pyrrol-2-ylphosphonates and Their Coupling with Aldehydes. Application to the Synthesis of C/D-Rings Component of Phycocyanobilin

    OpenAIRE

    Ngwe, Hla; Kinoshita, Hideki; Inomata, Katsuhiko

    1994-01-01

    Diethyl 3,4-disubstituted 1,5-dihydro-5-oxo-2H-pyrrol-2-ylphosphonates were regioselectively prepared by acidic hydrolysis of diethyl 3,4-disubstituted 5-bromo-2-pyrrolylphosphonates. The resulting 1,5-dihydro-2H-pyrrol-2-ones readily underwent the coupling reaction with various aldehydes to afford the corresponding 1,5-dihydro-5-methylene-2H-pyrrol-2-ones including pyrromethenone derivatives in good yields. A series of these reactions was successfully applied to the synthesis of C/D-rings co...

  17. Hemispherand-Strapped Calix[4]pyrrole: An Ion-pair Receptor for the Recognition and Extraction of Lithium Nitrite.

    Science.gov (United States)

    He, Qing; Zhang, Zhan; Brewster, James T; Lynch, Vincent M; Kim, Sung Kuk; Sessler, Jonathan L

    2016-08-10

    The hemispherand-strapped calix[4]pyrrole (1) acts as an ion pair receptor that exhibits selectivity for lithium salts. In organic media (CD2Cl2 and CD3OD, v/v, 9:1), receptor 1 binds LiCl with high preference relative to NaCl, KCl, and RbCl. DFT calculations provided support for the observed selectivity. Single crystal structures of five different lithium ion-pair complexes of 1 were obtained. In the case of LiCl, a single bridging water molecule between the lithium cation and chloride anion was observed, while tight contact ion pairs were observed in the case of the LiBr, LiI, LiNO3, and LiNO2 salts. Receptor 1 proved effective as an extractant for LiNO2 under both model solid-liquid and liquid-liquid extraction conditions. PMID:27442768

  18. Large area in situ fabrication of poly(pyrrole)-nanowires on flexible thermoplastic films using nanocontact printing

    Science.gov (United States)

    Garcia-Cruz, Alvaro; Lee, Michael; Marote, Pedro; Zine, Nadia; Sigaud, Monique; Bonhomme, Anne; Pruna, Raquel; Lopez, Manuel; Bausells, Joan; Jaffrezic, Nicole; Errachid, Abdelhamid

    2016-08-01

    Highly efficient nano-engineering tools will certainly revolutionize the biomedical and sensing devices research and development in the years to come. Here, we present a novel high performance conducting poly(pyrrole) nanowires (PPy-NW) patterning technology on thermoplastic surfaces (poly(ethylene terephthalate (PETE), poly(ethylene 2,6-naphthalate (PEN), polyimide (PI), and cyclic olefin copolymer) using nanocontact printing and controlled chemical polymerization (nCP-CCP) technique. The technique uses a commercial compact disk as a template to produce nanopatterned polydimethylsiloxane (PDMS) stamps. The PDMS nanopatterned stamp was applied to print the PPy-NWs and the developed technology of nCP-CCP produced 3D conducting nanostructures. This new and very promising nanopatterning technology was achieved in a single step and with a low cost of fabrication over large areas.

  19. Excited state non-adiabatic dynamics of pyrrole: A time-resolved photoelectron spectroscopy and quantum dynamics study

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Guorong [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023 (China); Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Neville, Simon P.; Worth, Graham A., E-mail: g.a.worth@bham.ac.uk [School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT (United Kingdom); Schalk, Oliver [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Department of Physics, AlbaNova University Center, Stockholm University, Roslagstullsbacken 21, 109 61 Stockholm (Sweden); Sekikawa, Taro [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Department of Applied Physics, Hokkaido University, Kita-13 Nishi-8, Kita-ku, Sapporo 060-8628 (Japan); Ashfold, Michael N. R. [School of Chemistry, University of Bristol, Bristol BS8 1TS (United Kingdom); Stolow, Albert, E-mail: astolow@uottawa.ca [National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6 (Canada); Departments of Chemistry and Physics, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5 (Canada)

    2015-02-21

    The dynamics of pyrrole excited at wavelengths in the range 242-217 nm are studied using a combination of time-resolved photoelectron spectroscopy and wavepacket propagations performed using the multi-configurational time-dependent Hartree method. Excitation close to the origin of pyrrole’s electronic spectrum, at 242 and 236 nm, is found to result in an ultrafast decay of the system from the ionization window on a single timescale of less than 20 fs. This behaviour is explained fully by assuming the system to be excited to the A{sub 2}(πσ{sup ∗}) state, in accord with previous experimental and theoretical studies. Excitation at shorter wavelengths has previously been assumed to result predominantly in population of the bright A{sub 1}(ππ{sup ∗}) and B{sub 2}(ππ{sup ∗}) states. We here present time-resolved photoelectron spectra at a pump wavelength of 217 nm alongside detailed quantum dynamics calculations that, together with a recent reinterpretation of pyrrole’s electronic spectrum [S. P. Neville and G. A. Worth, J. Chem. Phys. 140, 034317 (2014)], suggest that population of the B{sub 1}(πσ{sup ∗}) state (hitherto assumed to be optically dark) may occur directly when pyrrole is excited at energies in the near UV part of its electronic spectrum. The B{sub 1}(πσ{sup ∗}) state is found to decay on a timescale of less than 20 fs by both N-H dissociation and internal conversion to the A{sub 2}(πσ{sup ∗}) state.

  20. Preparation and characterization of poly-pyrrole thin films functionalized by ion exchanger groups. Application to preparation of alpha sources

    International Nuclear Information System (INIS)

    After having outlined that dosing methods still present problems related to chemical separations techniques used before radioactivity measurements, and to spectrometric methods, this research thesis proposes the study of a new method of fabrication of a radioactive source. This method comprises the fabrication of a chemically reactive thin film by electro-polymerization, and the incorporation of actinides in the deposit by ion exchange. In this case, the deposit thickness could be controlled and the material transfer chemical mechanisms could be predicted and controlled

  1. Post Hartree–Fock and DFT Studies on Pyrrole···Nitrogen and Pyrrole···Carbon Monoxide Molecules

    Directory of Open Access Journals (Sweden)

    P. Kolandaivel

    2002-07-01

    Full Text Available Abstract: The hydrogen bonded and van der Waals isomers of pyrrole···nitrogen and pyrrole···carbon monoxide have been studied using ab initio and density functional theory methods. Complex geometries and total energies of the isomers have been determined at HF, MP2, B3LYP and B3PW91 levels of theory employing 6-31G* basis set. For pyrrole···nitrogen complex, only two isomers have stable structure and the more stable one is found to be the hydrogen bonded isomer. Among the five isomers of pyrrole···carbon monoxide complex, the hydrogen bonded isomer is found to be the most stable form. The interaction energy for all these isomers have been calculated after eliminating the basis set superposition errors by using the full counterpoise correction method. Chemical hardness, chemical potential have been calculated and are used to study the stability of the molecules.

  2. Synthesis and phototoxicity of isomeric 7,9-diglutathione pyrrole adducts: Formation of reactive oxygen species and induction of lipid peroxidation

    Directory of Open Access Journals (Sweden)

    Liang Ma

    2015-09-01

    Full Text Available Pyrrolizidine alkaloids (PAs are hepatotoxic, genotoxic, and carcinogenic in experimental animals. Because of their widespread distribution in the world, PA-containing plants are probably the most common poisonous plants affecting livestock, wildlife, and humans. Upon metabolism, PAs generate reactive dehydro-PAs and other pyrrolic metabolites that lead to toxicity. Dehydro-PAs are known to react with glutathione (GSH to form 7-GSH-(+/−-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (7-GS-DHP in vivo and in vitro and 7,9-diGS-DHP in vitro. To date, the phototoxicity of GS-DHP adducts has not been well studied. In this study, we synthesized 7-GS-DHP, a tentatively assigned 9-GS-DHP, and two enantiomeric 7,9-diGS-DHP adducts by reaction of dehydromonocrotaline with GSH. The two 7,9-diGS-DHPs were separated by high performance liquid chromatography (HPLC and their structures were characterized by 1H nuclear magnetic resonance (NMR and 1H–1H correlation spectroscopy (COSY NMR spectral analysis. Photoirradiation of 7-GS-DHP, 9-GS-DHP, and the two 7,9-diGS-DHPs as well as dehydromonocrotaline, dehydroheliotrine, and the 7-R enantiomer of DHP (DHR, by UVA light at 0 J/cm2, 14 J/cm2, and 35 J/cm2 in the presence of a lipid, methyl linoleate, all resulted in lipid peroxidation in a light dose-responsive manner. The levels of lipid peroxidation induced by the two isomeric 7,9-diGS-DHPs were significantly higher than that by 7-GS-DHP and 9-GS-DHP. When 7,9-diGS-DHP was irradiated in the presence of sodium azide (NaN3, the level of lipid peroxidation decreased; lipid peroxidation was enhanced when methanol was replaced by deuterated methanol. These results suggest that singlet oxygen is a product induced by the irradiation of 7,9-diGS-DHP. When irradiated in the presence of superoxide dismutase (SOD, the level of lipid peroxidation decreased, indicating that lipid peroxidation is also mediated by superoxide. These results indicate that lipid

  3. Complete dechlorination of 2,4-dichlorophenol in aqueous solution on palladium/polymeric pyrrole-cetyl trimethyl ammonium bromide/foam-nickel composite electrode

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Zhirong, E-mail: zrsun@bjut.edu.cn [College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Wei, Xuefeng; Han, Yanbo; Tong, Shan [College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Hu, Xiang, E-mail: huxiang99@163.com [College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029 (China)

    2013-01-15

    Highlights: ► Pd/PPy-CTAB/foam-Ni electrode with high surface area and low Pd content was prepared. ► The composite electrode was applied to dechlorination of 2,4-DCP in aqueous solution. ► Complete dechlorination of 2,4-DCP was achieved with higher current efficiency. ► Removal efficiency kept 100% after 10 times dechlorination on the stable electrode. ► The electrochemically reductive activation energy was 25.8 kJ mol{sup −1} in this system. -- Abstract: The electrochemically reductive dechlorination of 2,4-dichlorophenol (2,4-DCP) in aqueous solution on palladium/polymeric pyrrole-cetyl trimethyl ammonium bromide/foam-nickel electrode (Pd/PPy-CTAB/foam-Ni electrode) was investigated in this paper. Pd/PPy-CTAB/foam-Ni electrode was prepared and characterized by cyclic voltammetry (CV), scanning electron microscope (SEM), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) adsorption and inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The influences of some experimental factors such as the dechlorination current, dechlorination time and the initial pH on the removal efficiency and the current efficiency of 2,4-DCP dechlorination on Pd/PPy-CTAB/foam-Ni electrode were studied. Complete removal of 2,4-DCP was achieved and the current efficiency of 47.4% could be obtained under the conditions of the initial pH of 2.2, the dechlorination current of 5 mA and the dechlorination time of 50 min when the initial 2,4-DCP concentration was 100 mg L{sup −1}. The analysis of high performance liquid chromatography (HPLC) identified that the intermediate products were 2-chlorophenol (2-CP) and 4-chlorophenol (4-CP). The final products were mainly phenol. Its further reduction product cyclohexanone was also detected. The electrocatalytic dechlorination pathways of 2,4-DCP on Pd/PPy-CTAB/foam-Ni electrode were discussed. The stability of the electrode was favorable that it could keep dechlorination efficiency at 100% after having been reused

  4. Silica sulfuric acid: a reusable solid catalyst for one pot synthesis of densely substituted pyrrole-fused isocoumarins under solvent-free conditions

    Directory of Open Access Journals (Sweden)

    Sudipta Pathak

    2013-11-01

    Full Text Available A convenient and efficient methodology for the synthesis of densely substituted pyrrole-fused isocoumarins, which employs solid-supported silica sulfuric acid (SSA as catalyst, has been developed. When the mixture of ninhydrin adducts of acetylacetone/ethyl acetoacetate and primary amines was heated on the solid surface of SSA under solvent-free conditions, the pyrrole-fused isocoumarins were formed in good yields. This synthetic method has several advantages such as the employment of solvent-free reaction conditions without the use of any toxic reagents and metal catalysts, the ease of product isolation, the use of a recyclable catalyst, the low cost, the easy availability of the starting materials, and the excellent yields of products.

  5. Electrochemical dechlorination of chloroform in neutral aqueous solution on palladium/foam-nickel and palladium/polymeric pyrrole film/foam-nickel electrodes

    Institute of Scientific and Technical Information of China (English)

    SUN Zhirong; LI Baohua; HU Xiang; SHI Min; HOU Qingnan; PENG Yongzhen

    2008-01-01

    Electrochemical dechlonnafion of chloroform in neutral aqueous solution was investigated using palladium-loaded electrodes at ambient temperature.Palladium/foam-nickel (Pd/foam-Ni) and palladium/polymeric pyrrole film/foam-nickel (Pd/PPy/foam-Ni)composite electrodes which provided catalytic surface for reductive dechiorination of chloroform in aqueous solution were prepared using an electrodepositing method.Scanning electron microscope (SEM) micrographs showed that polymeric pyrrole film modified the electrode-surface characteristics and resulted in the uniform dispersion of needle-shaped palladium particles on foam-Ni supporting electrode.The experimental results of dechlorination indicated that the removal efficiency of chloroform and current efficiency in neutral aqueous solution on Pd/PPy/foam-Ni electrode could be up to 36.8% and 33.0% at dechlorination current of 0.1 mA and dechlorination time of 180 rain,which is much higher than that of Pd/foam-Ni electrode.

  6. 3-(Dicyanomethylidene)indan-1-one-Functionalized Calix[4]arene-Calix[4]pyrrole Hybrid: An Ion-Pair Sensor for Cesium Salts.

    Science.gov (United States)

    Yeon, Yerim; Leem, Soojung; Wagen, Corin; Lynch, Vincent M; Kim, Sung Kuk; Sessler, Jonathan L

    2016-09-01

    A chromogenic calix[4]arene-calix[4]pyrrole hybrid ion pair receptor bearing an indane substituent at a β-pyrrolic position has been prepared. On the basis of solution-phase UV-vis spectroscopic analysis and (1)H NMR spectroscopic studies carried out in 10% methanol in chloroform, receptor 1 is able to bind only cesium ion pairs (e.g., CsF, CsCl, and CsNO3) but not the constituent cesium cation (as its perchlorate salt) or the F(-), Cl(-), or NO3(-) anions (as the tetrabutylammonium salts). It thus displays rudimentary AND logic gate behavior. Receptor 1 shows a colorimetric response to cesium ion pairs under conditions of solid-liquid (nitrobenzene) and liquid-liquid (D2O-nitrobenzene-d5) extraction. PMID:27533478

  7. A Convenient Method for the Preparation of 1,5-Diaryl-3-(arylamino)-I H-pyrrol-2(5 H)-ones

    Institute of Scientific and Technical Information of China (English)

    Ghashang, Majid; Shaterian, Hamid Reza~

    2011-01-01

    A simple and eco-friendly method for the preparation of 1,5-diaryl-3-(arylamino)-lH-pyrrol-2(5H)-ones via the cyclo-condensation reaction of aldehydes, amines and ethyl pyruvate in the presence of silica supported ferric chlo- ride (SiO2-FeCl3) as reusable heterogeneous catalyst is described. The present methodology offers several advantages such as excellent yields, simple procedure and short reaction times.

  8. 2,2′,5,5′-Tetramethyl-1,1′-(hexane-1,6-diyldi-1H-pyrrole

    Directory of Open Access Journals (Sweden)

    Ana C. Santos

    2009-07-01

    Full Text Available The molecule of the title compound, C18H28N2, composed of two 2,5-dimethylpyrrole groups linked by a hexane chain, lies across a crystallographic inversion centre. The mean plane of the pyrrole ring is almost perpendicular to the mean plane of the central chain, making a dihedral angle of 89.09 (8°. The crystal structure is stabilized by intermolecular C—H...π interactions.

  9. Stereoselective self-sorting in the self-assembly of a Phe-Phe extended guanidiniocarbonyl pyrrole carboxylate zwitterion: formation of two diastereomeric dimers with significantly different stabilities.

    Science.gov (United States)

    Rodler, Fabian; Sicking, Wilhelm; Schmuck, Carsten

    2011-07-28

    The 'dipeptide extended' guanidiniocarbonyl pyrrole carboxylate zwitterion GCP-Phe-Phe 1 forms stable dimers in DMSO. However, dimerization is highly stereoselective. Only homochiral dimers are formed and the (L,L)·(L,L) dimer (K(dim) > 10(5) M(-1)) is significantly more stable by a factor of 10(3) than the diastereomeric (D,L)·(D,L) dimer (K(dim) = 120 M(-1)). PMID:21670799

  10. Photocatalytic Degradation of Eosin Yellow Using Poly(pyrrole-co-aniline)-Coated TiO2/Nanocellulose Composite under Solar Light Irradiation

    OpenAIRE

    Anirudhan, T. S.; Rejeena, S. R.

    2015-01-01

    The present study describes the feasibility of a novel adsorbent cum photocatalyst, poly(pyrrole-co-aniline)-coated TiO2/nanocellulose composite (P(Py-co-An)-TiO2/NCC), to remove eosin yellow (EY) from aqueous solutions. The removal of EY was investigated by batch adsorption followed by photocatalysis. The effect of various adsorption parameters like adsorbent dose, pH, contact time, initial concentration, and ionic strength has been optimized for treating effluents from the dye industry. Ads...

  11. Antitumor Activity of a 5-Hydroxy-1H-Pyrrol-2-(5H-One-Based Synthetic Small Molecule In Vitro and In Vivo.

    Directory of Open Access Journals (Sweden)

    Yunyun Geng

    Full Text Available Alternative chemo-reagents are in great demand because chemotherapy resistance is one of the major challenges in current cancer treatment. 5-hydoxy-1H-pyrrol-2-(5H-one is an important N-heterocyclic scaffold that is present in natural products and medicinal chemistry. However, its antitumor activity has not been systematically explored. In this study, we screened a panel of 5-hydoxy-1H-pyrrol-2-(5H-one derivatives and identified compound 1d as possessing strong anti-proliferative activity in multiple cancer cell lines. Cell cycle analysis revealed that 1d can induce S-phase cell cycle arrest and that HCT116 was sensitive to 1d-induced apoptosis. Further analysis indicated that 1d preferentially induced DNA damage and p53 activation in HCT116 cells and that 1d-induced apoptosis is partly dependent on p53. Furthermore, we showed that 1d significantly suppressed tumor growth in xenograft tumor models in vivo. Taken together, our results suggest that 5-hydoxy-1H-pyrrol-2-(5H-one derivatives bear potential antitumor activity and that 1d is an effective agent for cancer treatment.

  12. Orange to black electrochromic behaviour in poly(2-(2-thienyl)-1H-pyrrole) thin films

    International Nuclear Information System (INIS)

    We have studied an electrochromic precursor, 2-(2-thienyl)-1H-pyrrole (1), using two improved procedures of the Trofimov reaction. Optimised stereochemical calculations at the B3LYP/6-311G* level showed almost equal s-cis and s-trans conformational populations in 1 with marked out-of-plane deviations of ca. 30o. Model calculations suggest that the predominant rotational conformation in undoped poly(1) would be s-trans with the essential out-of-plane deviations around the all three interheterocyclic bonds of ca. 25-30o. Monomer 1 exhibited two irreversible oxidation processes at +0.86 and +1.3 V corresponding to the oxidation of the pyrrole and thiophene rings, respectively. Orange to black electrochromic behaviour was found in ClO4- doped poly(1) thin films with colouring and bleaching times of 1.8 and 1.3 s, respectively. The colouration efficiency during the bleaching process was 233 cm2/C. The optical contrast at 450 nm was 19% and in the near-IR was 36%. The band-gap of poly(1) (1.6-1.7 eV) was found to be significantly lower than that of polypyrrole (2.85 eV) and polythiophene (2.3 eV) as a consequence of increased electron delocalisation in the system. Important differences in the morphology of doped and dedoped poly(1) films were observed by atomic-force microscopy (AFM). Doped poly(1) films showed a granular morphology with primary particles of 45-60 nm in size and an average surface roughness of 3.5 nm. On the other hand, dedoped poly(1) films showed interconnected aggregates of 65-90 nm in size as a consequence of particle fusion, with a surface roughness of 9.2 nm. In summary, poly(1) is a promising material for emerging flexible electrochromic devices such as displays and variable optical attenuators

  13. Preparation of thin {alpha}-particle sources using poly-pyrrole films functionalized by a chelating agent; Preparation de sources minces d'emetteurs alpha a l'aide de films de polypyrrole fonctionnalises par un ligand chelatant

    Energy Technology Data Exchange (ETDEWEB)

    Mariet, C. [CEA Saclay, INSTN, Institut National des Sciences et Techniques Nucleaires, 91 - Gif-sur-Yvette (France); Universite Pierre et Marie Curie, 75 - Paris (France)

    2000-07-01

    This work takes place in the scope of analysis of the {alpha}-particle emitting elements U, Pu and Am present in compound environmental matrix like sols and sediments. The samples diversity and above all the {alpha}-ray characteristics require the analyst to implement a sequence of chemical steps in which the more restricting is the actinides concentration in a uniform and thin layer en allowing an accurately measure of alpha activity. On this account, we studied a new technique for radioactive sources preparation based on tow steps: preparation of a thin film as source support; incorporation of radioactive elements by a chelating extraction mechanism. The thin films were obtained through electro-polymerization of pyrrole monomer functionalized by an chelating ligand able to extract actinides from concentrated acidic solutions. Polymerization conditions of this monomer were perfected, then obtained films were characterized from a physico-chemical point of view. We point out their extracting properties were comparable to (retention capacity, distribution coefficient) to those of usual ion-exchange resins. The underscore of uranyl and americium nitrate complexes formed in the thin layer allowed to calculate the extraction constants in case acid extraction is negligible. Thanks to this results, the values of the coefficients distribution D{sub U} and D{sub Am} could be provided for all nitric solutions in which acid extraction is negligible. Optimal actinides retention conditions in the polymer were defined and used to settle a protocol for plutonium analysis in environmental samples. (author)

  14. Comparative neurotoxicity and pyrrole-forming potential of 2,5-hexanedione and perdeuterio-2,5-hexanedione in the rat

    Energy Technology Data Exchange (ETDEWEB)

    DeCaprio, A.P.; Briggs, R.G.; Jackowski, S.J.; Kim, J.C.

    1988-01-01

    2,5-Hexanedione (2,5-HD), the neurotoxic metabolite of n-hexane, reacts with protein amines to form alkylpyrrole adducts. Pyrrolylation of neurofilament protein may be the initiating molecular event in 2,5-HD neuropathy. The present study compares the neurotoxic and pyrrole-forming potentials of 2,5-HD with those of perdeuterio-2,5-HD ((D10)-2,5-HD) in the rat. Due to a requirement for C-H bond breaking in the reaction mechanism, the latter derivative was expected to exhibit a primary isotope effect, thus forming the pyrrole at a slower rate. In vitro studies confirmed that (D10)-2,5-HD pyrrolylated protein at only one-third of the initial rate seen with native 2,5-HD. Prolonged incubation resulted in similar pyrrole concentrations with both derivatives. Adult, male Wistar rats were administered daily (5 days/week) ip doses of either 3.5 mmol 2,5-HD or (D10)-2,5-HD/kg/day for 17 days or 2.5 mmol/kg/day for 38 days. At termination, animals administered 2,5-HD and (D10)-2,5-HD exhibited 27 and 8% body weight loss, respectively. Moderate to severe hindlimb paralysis was present in the 2,5-HD groups while only mild effects were seen in (D10)-2,5-HD-dosed rats. Neuropathological changes were prominent in spinal cord sections from 2,5-HD-treated animals, while no effects were present in rats given the deuterated derivative. Pyrrole adduct concentrations in serum and axonal cytoskeletal proteins from 2,5-HD-treated animals were two- to threefold higher than in rats given equimolar doses of (D10)-2,5-HD. Levels of covalent crosslinking of axonal cytoskeletal proteins (assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis) appeared to correlate with pyrrole concentrations. Tissue concentrations of each diketone isomer were not significantly different, indicating similar uptake of native and deuterated 2,5-HD.

  15. A pyrrole quinoline quinone glucose dehydrogenase biosensor based on screen-printed carbon paste electrodes modified by carbon nanotubes

    International Nuclear Information System (INIS)

    A carbon nanotube (CNT) modified biosensor based on oxygen-independent, pyrrole quinoline quinone glucose dehydrogenase (PQQ-GDH) for monitoring glucose was studied. The disposable amperometric biosensors based on screen-printed carbon paste electrodes are low cost and suitable for mass production. Potassium ferricyanide was immobilized on the surface of the electrodes as an electron mediator, which decreased the work potential. The biosensor showed a linear amperometric response to glucose from 1 to 35 mM, with a sensitivity of 31.0 µA mM−1 cm−2. Experimentally, the compositions of PQQ-GDH, potassium ferricyanide, CNTs and other components were evaluated and optimized. Only 2 µl of sample are needed for one test, and the response time of the sensor is 20 s. The characteristics of the biosensor were studied through cyclic voltammetry, and experimental results showed that the CNTs could facilitate the electron transfer between the enzyme and electrode surface significantly. Compared with the biosensor without carbon nanotube modification, the CNTs improved the sensitivity of the biosensor up to five times

  16. One electron vs. two electron electrochemical and chemical oxidation of electron-donor substituted diketo-pyrrolo-pyrroles

    International Nuclear Information System (INIS)

    Electrochemical and chemical (using FeCl3) oxidation reactions of a series of eight N,N′-dialkylated soluble diketo-pyrrolo-pyrrole dyes (DPPs) substituted by electron donating and/or electron withdrawing groups were investigated electrochemically and by UV–vis spectrometry and the results were rationalized by DFT calculations. Influence of substituents on HOMO and LUMO energies as well as on the electron transfer mechanism was followed. Destabilization of HOMO by two piperidino-substituents in 3,6-diphenyl-DPP 5 enabled to observe a potential inversion in electrochemical oxidation of this derivative, when a two-electron oxidation occurs leading directly to a dication, whereas other DPPs are oxidized first in a one-electron transfer to a radical cation. In chemical oxidation with FeCl3 the radical cation is produced by two mechanisms: either directly (standard reaction) or in the case of 5 by a comproportionation reaction of neutral molecule and its dication. Using mutual comparison of oxidation potentials and HOMO/LUMO energies a quite realistic limit of FeCl3 oxidation ability in acetonitrile was found

  17. Effect of non-electroactive additives on the early stage pyrrole electropolymerization on indium tin oxide electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Castro-Beltran, A. [Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Ave. Pedro de Alba s/n, Ciudad Universitaria, C.P. 66451 San Nicolás de los Garza, N.L. (Mexico); Centro de Innovación Investigación y Desarrollo en Ingeniería y Tecnología (CIIDIT), Universidad Autónoma de Nuevo León, PIIT-Monterrey C.P. 66600 Apodaca, N.L. (Mexico); Dominguez, C.; Bahena-Uribe, D. [Centro Investigación en Ingeniería y Ciencias Aplicadas (CIICAp), Universidad Autónoma del Estado de Morelos, Av. Universidad 1001, Col. Chamilpa, C.P. 62209 Cuernavaca, Mor. (Mexico); Sepulveda-Guzman, S., E-mail: selene.sepulvedagz@uanl.edu.mx [Facultad de Ingeniería Mecánica y Eléctrica, Universidad Autónoma de Nuevo León, Ave. Pedro de Alba s/n, Ciudad Universitaria, C.P. 66451 San Nicolás de los Garza, N.L. (Mexico); Centro de Innovación Investigación y Desarrollo en Ingeniería y Tecnología (CIIDIT), Universidad Autónoma de Nuevo León, PIIT-Monterrey C.P. 66600 Apodaca, N.L. (Mexico); Cruz-Silva, R. [Research Center for Exotic NanoCarbon, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553 (Japan)

    2014-09-01

    The use of non-electroactive additives during electrodeposition of conducting polymers has long been used to modify the properties of deposited films. These additives can improve the adhesion, and not only change the morphology and deposition rate but also modify the chemical composition of the electrodeposited polymer. Several compounds have been used to modify deposition of polypyrrole; however, there is no systematic study of these compounds. In this work, we comparatively studied several water soluble chemical compounds, a cationic polymer, an anionic polymer, a cationic surfactant, and an anionic surfactant during potentiostatic electrodeposition of polypyrrole. In order to study the effect of these compounds on the interface, where the electrochemical polymerization takes place, we used electrochemical impedance spectroscopy. The morphology during the initial stage of growth was studied by atomic force microscopy, whereas the resulting polypyrrole films were observed by scanning electron microscopy. - Highlights: • Early-stage polymerization polypyrrole particles on indium tin oxide (ITO). • Anionic additives promote pyrrole oxidation and polypyrrole film growth on ITO. • Cationic polyelectrolyte promotes adhesion between ITO and polypyrrole film. • Non-electroactive additives strongly influence polypyrrole nucleation on ITO.

  18. Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Tsung, Chia-Kuang; Kuhn, John N.; Huang, Wenyu; Aliaga, Cesar; Hung, Ling-I; Somorjai, Gabor A.; Yang, Peidong

    2009-03-02

    Platinum nanocubes and nanopolyhedra with tunable size from 5 to 9 nm were synthesized by controlling the reducing rate of metal precursor ions in a one-pot polyol synthesis. A two-stage process is proposed for the simultaneous control of size and shape. In the first stage, the oxidation state of the metal ion precursors determined the nucleation rate and consequently the number of nuclei. The reaction temperature controlled the shape in the second stage by regulation of the growth kinetics. These well-defined nanocrystals were loaded into MCF-17 mesoporous silica for examination of catalytic properties. Pt loadings and dispersions of the supported catalysts were determined by elemental analysis (ICP-MS) and H2 chemisorption isotherms, respectively. Ethylene hydrogenation rates over the Pt nanocrystals were independent of both size and shape and comparable to Pt single crystals. For pyrrole hydrogenation, the nanocubes enhanced ring-opening ability and thus showed a higher selectivity to n-butylamine as compared to nanopolyhedra.

  19. Pyrrole Hydrogenation over Rh(111) and Pt(111) Single-Crystal Surfaces and Hydrogenation Promotion Mediated by 1-Methylpyrrole: A Kinetic and Sum-Frequency Generation Vibrational Spectroscopy Study

    Energy Technology Data Exchange (ETDEWEB)

    Kliewer, Christopher J.; Bieri, Marco; Somorjai, Gabor A.

    2008-03-04

    Sum-frequency generation (SFG) surface vibrational spectroscopy and kinetic measurements using gas chromatography have been used to study the adsorption and hydrogenation of pyrrole over both Pt(111) and Rh(111) single-crystal surfaces at Torr pressures (3 Torr pyrrole, 30 Torr H{sub 2}) to form pyrrolidine and the minor product butylamine. Over Pt(111) at 298 K it was found that pyrrole adsorbs in an upright geometry cleaving the N-H bond to bind through the nitrogen evidenced by SFG data. Over Rh(111) at 298 K pyrrole adsorbs in a tilted geometry relative to the surface through the p-aromatic system. A pyrroline surface reaction intermediate, which was not detected in the gas phase, was seen by SFG during the hydrogenation over both surfaces. Significant enhancement of the reaction rate was achieved over both metal surfaces by adsorbing 1-methylpyrrole before reaction. SFG vibrational spectroscopic results indicate that reaction promotion is achieved by weakening the bonding between the N-containing products and the metal surface because of lateral interactions on the surface between 1-methylpyrrole and the reaction species, reducing the desorption energy of the products. It was found that the ring-opening product butylamine was a reaction poison over both surfaces, but this effect can be minimized by treating the catalyst surfaces with 1-methylpyrrole before reaction. The reaction rate was not enhanced with elevated temperatures, and SFG suggests desorption of pyrrole at elevated temperatures.

  20. Research on interfacial polymerization of pyrrole assist with Span80 system

    Science.gov (United States)

    Yang, Q. H.; Tu, Z. Y.; Zhao, N. Y.

    2016-07-01

    With assistance of surfactants, self-assembled Polypyrrole (PPy) film was prepared via oil / water interfacial polymerization. The chemical structure and morphologies of the obtained samples have been characterized by Fourier transform infrared (FT-IR) and Scanning Electron Microscope (SEM), respectively. The electrochemical performance recorded on an electrochemical workstation, mainly includes cyclic voltammetry (CV) tests. The prepared PPy film has its own extremely vesicular structures from results and indicates by using different concentration surfactant Span80. The PPy film prepared 25 °C with 3.32 g/L Span80 (surpass its critical micelle concentration) as a surfactant possess a supernal specific capacitance of 368.18 F/g at a scan rate 50 mV/s in 1 M NaNO3 aqueous solution at.

  1. Metalloporphyrins with all the pyrrole nitrogens replaced with phosphorus atoms, MP(P)4 (M = Sc, Ti, Fe, Ni, Cu, Zn)

    International Nuclear Information System (INIS)

    Highlights: • First systematic DFT study of the MP(P)4 compounds with increasing number of d-electrons. • Complete substitution of pyrrole nitrogens by P-atoms does not change the ground spin state. • Complete substitution of pyrrole nitrogens by P-atoms results in a bowl-like shape. • Significant stabilization of the MP(P)4 LUMOs compared to the MP counterparts. • MP(P)4 HOMO/LUMO gaps are smaller than the MP HOMO/LUMO gaps. - Abstract: We performed first systematic DFT study of the structures and electronic features (frontier orbitals energies, HOMO/LUMO and optical gaps, IPs and EAs) of the MP(P)4 compounds, with increasing number of d-electrons: 3d14s2 (Sc) → 3d24s2 (Ti) → 3d64s2 (Fe) → 3d84s2 (Ni) → 3d104s1 (Cu) → 3d104s2 (Zn). We performed systematic comparison with the tetrapyrrole MP counterparts. Complete substitution of the pyrrole nitrogens by P-atoms does not change the calculated ground spin state of the compound. All the MP(P)4 species adopt a bowl-like shape, compared to generally planar or slightly distorted shapes of their MP counterparts. Significant positive charge accumulates on P-atoms in MP(P)4. Positive charges on the metals in MP(P)4 are noticeably lower than in the MP counterparts. The calculated MP(P)4 HOMO/LUMO gaps and optical gaps are noticeably smaller than the corresponding gaps in their MP counterparts, which is explained by stabilization of the MP(P)4 LUMOs

  2. Metalloporphyrins with all the pyrrole nitrogens replaced with phosphorus atoms, MP(P){sub 4} (M = Sc, Ti, Fe, Ni, Cu, Zn)

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, Aleksey E., E-mail: aleksey73kuznets@gmail.com

    2015-02-02

    Highlights: • First systematic DFT study of the MP(P){sub 4} compounds with increasing number of d-electrons. • Complete substitution of pyrrole nitrogens by P-atoms does not change the ground spin state. • Complete substitution of pyrrole nitrogens by P-atoms results in a bowl-like shape. • Significant stabilization of the MP(P){sub 4} LUMOs compared to the MP counterparts. • MP(P){sub 4} HOMO/LUMO gaps are smaller than the MP HOMO/LUMO gaps. - Abstract: We performed first systematic DFT study of the structures and electronic features (frontier orbitals energies, HOMO/LUMO and optical gaps, IPs and EAs) of the MP(P){sub 4} compounds, with increasing number of d-electrons: 3d{sup 1}4s{sup 2} (Sc) → 3d{sup 2}4s{sup 2} (Ti) → 3d{sup 6}4s{sup 2} (Fe) → 3d{sup 8}4s{sup 2} (Ni) → 3d{sup 10}4s{sup 1} (Cu) → 3d{sup 10}4s{sup 2} (Zn). We performed systematic comparison with the tetrapyrrole MP counterparts. Complete substitution of the pyrrole nitrogens by P-atoms does not change the calculated ground spin state of the compound. All the MP(P){sub 4} species adopt a bowl-like shape, compared to generally planar or slightly distorted shapes of their MP counterparts. Significant positive charge accumulates on P-atoms in MP(P){sub 4}. Positive charges on the metals in MP(P){sub 4} are noticeably lower than in the MP counterparts. The calculated MP(P){sub 4} HOMO/LUMO gaps and optical gaps are noticeably smaller than the corresponding gaps in their MP counterparts, which is explained by stabilization of the MP(P){sub 4} LUMOs.

  3. A DFT Study of Pyrrole-Isoxazole Derivatives as Chemosensors for Fluoride Anion

    Directory of Open Access Journals (Sweden)

    Shanshan Tang

    2012-09-01

    Full Text Available The interactions between chemosensors, 3-amino-5-(4,5,6,7-tetrahydro-1H-indol-2-ylisoxazole-4-carboxamide (AIC derivatives, and different anions (F Cl, Br, AcO, and H2PO4 have been theoretically investigated using DFT approaches. It turned out that the unique selectivity of AIC derivatives for F is ascribed to their ability of deprotonating the host sensors. Frontier molecular orbital (FMO analyses have shown that the vertical electronic transitions of absorption and emission for the sensing signals are characterized as intramolecular charge transfer (ICT. The study of substituent effects suggests that all the substituted derivatives are expected to be promising candidates for fluoride chemosensors both in UV-vis and fluorescence spectra except for derivative with benzo[d]thieno[3,2-b]thiophene fragment that can serve as ratiometric fluorescent fluoride chemosensor only.

  4. The Synthesis of Novel 3-Substituted Poly(pyrroles) Bearing Crown-ether Moieties and a Study of their Electrochemical Properties

    DEFF Research Database (Denmark)

    Guernion, Nicolas J.L.; Blencowe, A.; Hayes, Wayne;

    2006-01-01

    polypyrrole derivatives was characterised by Scanning Electron Microscopy (SEM). These polymers exhibited an open porous structure and half the charge was required when compared to polypyrrole to afford films of equal thickness. The mass change during polymerisation was followed by Electrochemical Quartz......A series of fourteen novel pyrrole monomers substituted at the 3-position with aliphatic and aromatic crown-ether moieties have been synthesised in good yield and characterised extensively. Several of those compounds were electropolymerised successfully in acetonitrile, using both potentiostatic...... Crystal Microbalance measurement (EQCM), and the rate of polymer growth was found to be non-linear when compared to polypyrrole....

  5. Structure and spectroscopic properties of N,S-coordinating 2-methylsulfanyl-N-[(1H-pyrrol-2-ylmethylidene]aniline methanol monosolvate

    Directory of Open Access Journals (Sweden)

    D. Douglas Richards

    2015-10-01

    Full Text Available The reaction of pyrrole-2-carboxaldehyde and 2-(methylsulfanylaniline in refluxing methanol gave an olive-green residue in which yellow crystals of the title compound, C12H12N2S·CH3OH, were grown from slow evaporation of methanol at 263 K. In the crystal, hydrogen-bonding interactions link the aniline molecule and a nearby methanol solvent molecule. These units are linked by a pair of weak C—H...Omethanol interactions, forming inversion dimers consisting of two main molecules and two solvent molecules.

  6. 1-Benzoyl-3-[3-cyano-8-methyl-4-(1-methyl-1H-pyrrol-2-yl-5,6,7,8-tetrahydroquinolin-2-yl]thiourea

    Directory of Open Access Journals (Sweden)

    Abdullah M. Asiri

    2011-09-01

    Full Text Available In the N-substituted benzoylthiourea, C24H23N5OS, the benzoylthiourea unit is non-planar (r.m.s. deviation = 0.126 Å. The aliphatic part of the tetrahydroquinoline fused-ring system is disordered over two positions in a 0.592 (5:0.408 (5 ratio. The pyridine and pyrrole rings are twisted by 55.2 (1° in order to avoid crowding of their respective substituents. Pairs of molecules are linked by N—H...N hydrogen bonds, forming centrosymmetric dimers. Furthermore, an intramolecular N—H...O hydrogen bond stabilizes the molecular conformation.

  7. Ferrocene-Functionalized 4-(2,5-Di(thiophen-2-yl)-1H-pyrrol-1-yl)aniline: A Novel Design in Conducting Polymer-Based Electrochemical Biosensors

    OpenAIRE

    Rukiye Ayranci; Dilek Odaci Demirkol; Metin Ak; Suna Timur

    2015-01-01

    Herein, we report a novel ferrocenyldithiophosphonate functional conducting polymer and its use as an immobilization matrix in amperometric biosensor applications. Initially, 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)amidoferrocenyldithiophosphonate was synthesized and copolymerized with 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzenamine at graphite electrodes. The amino groups on the polymer were utilized for covalent attachment of the enzyme glucose oxidase. Besides, ferrocene on the backbon...

  8. High content of pyridinic- and pyrrolic-nitrogen-modified carbon nanotubes derived from blood biomass for the electrocatalysis of oxygen reduction reaction in alkaline medium

    International Nuclear Information System (INIS)

    Graphical abstract: Display Omitted -- Highlights: •An ORR electrocatalyst was fabricated from blood biomass and carbon nanotube. •The N-CNT catalyst exhibits good ORR activity, methanol resistance and stability. •The pyrolysis process produces high contents of pyridinic and pyrrolic N species. •The pyridinic-N group may play more important role in the active sites for ORR. -- Abstract: Here we present a facile synthetic route to design nitrogen-doped nanostructured carbon-based electrocatalyst for oxygen reduction reaction (ORR) by the copyrolysis of blood biomass from pig and carbon nanotubes (CNTs) at high temperatures. The nitrogen-doped CNTs obtained at 800 °C not only results in excellent ORR activity with four-electron transfer selectivity in alkaline medium, but also exhibits superior methanol-tolerant property and long-term stability. It is confirmed that high-temperature pyrolysis processes can facilitate to produce higher contents of pyridinic- and pyrrolic-N binding groups in electrocatalysts, contributing to the enhancement of ORR performance in terms of onset potential, half-wave potential, and limited current density. We also propose that the planar-N configuration may be the active site that is responsible for the improved ORR electrocatalytic performance. The straight-forward and cheap synthesis of the active and stable electrocatalyst makes it a promising candidate for electrochemical power sources such as fuel cells or metal-air batteries

  9. Conjugated and fluorescent polymer based on dansyl-substituted pyrrole prepared by electrochemical polymerization in acetonitrile containing boron trifluoride diethyl etherate

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • A fluorescent pyrrole derivative bearing a dansyl substituent (PyPDG) was synthesized. • PyPDG was electropolymerized onto ITO in (C4H9)4NBF4/CH3CN/BFEE mixed electrolyte. • The resulting polymer (PPyPDG) films displayed electrochromic behavior. • PPyPDG is a good green light emitter material. - Abstract: A fluorescent pyrrole derivative bearing a dansyl substituent was prepared by a simple synthetic route and electropolymerized onto Indium Tin Oxide (ITO) electrodes. The presence of the dansyl group in the monomer precursor prevents the electropolymerization in usual systems, such as (C4H9)4NBF4 in acetonitrile (CH3CN). For this reason, it was added 20% boron trifluoride diethyl etherate (BFEE) to this system, to achieve electropolymerization. The resulting poly[3-(N-pyrrolyl)propyl dansylglycinate] (PPyPDG) films displayed electrochromic behavior. Their color varied from greenish-yellow, in the neutral state, to greyish-green, in the oxidized state; moreover PPyPDG is a good green light emitter material. Therefore, PPyPDG films might be potentially applicable in displays and optoelectronic devices

  10. Strikingly different luminescent properties arising from single crystals grown from solution or from the vapor phase in a diketo-pyrrolo-pyrrole analog

    Science.gov (United States)

    Imoda, Tomohiko; Mizuguchi, Jin

    2007-10-01

    The title compound di-cyano-pyrrolo-pyrrole (DCPP) is an analog of diketo-pyrrolo-pyrrole (DPP) known as a red pigment on the market. Brilliant orange photoluminescence has been observed in crystals of DCPP recrystallized from solution (crystal I); whereas the luminescence was quite weak in single crystals grown from the vapor phase (crystal II). To elucidate the difference in luminescent properties, a series of structural analysis together with thermal analysis has been carried out on crystals I and II at -180 °C, RT, 150 °C, and 200 °C. However, no difference in structure is recognized between crystals I and II within the precision of the x-ray analysis. Nevertheless, a slight difference in sublimation temperature of about 5° is observed between crystals I and II. Since the sublimation temperature depends on the cohesion in the solid state and the cohesion, in turn, governs the extent of lattice vibration (i.e., nonradiative process), a slight difference in sublimation temperature appears to determine the fraction between the radiative and nonradiative processes in crystals I and II.

  11. Catalytic mechanisms of direct pyrrole synthesis via dehydrogenative coupling mediated by PNP-Ir or PNN-Ru pincer complexes: Crucial role of proton-transfer shuttles in the PNP-Ir system

    KAUST Repository

    Qu, Shuanglin

    2014-04-02

    Kempe et al. and Milstein et al. have recently advanced the dehydrogenative coupling methodology to synthesize pyrroles from secondary alcohols (e.g., 3) and β-amino alcohols (e.g., 4), using PNP-Ir (1) and PNN-Ru (2) pincer complexes, respectively. We herein present a DFT study to characterize the catalytic mechanism of these reactions. After precatalyst activation to give active 1A/2A, the transformation proceeds via four stages: 1A/2A-catalyzed alcohol (3) dehydrogenation to give ketone (11), base-facilitated C-N coupling of 11 and 4 to form an imine-alcohol intermediate (18), base-promoted cyclization of 18, and catalyst regeneration via H2 release from 1R/2R. For alcohol dehydrogenations, the bifunctional double hydrogen-transfer pathway is more favorable than that via β-hydride elimination. Generally, proton-transfer (H-transfer) shuttles facilitate various H-transfer processes in both systems. Notwithstanding, H-transfer shuttles play a much more crucial role in the PNP-Ir system than in the PNN-Ru system. Without H-transfer shuttles, the key barriers up to 45.9 kcal/mol in PNP-Ir system are too high to be accessible, while the corresponding barriers (<32.0 kcal/mol) in PNN-Ru system are not unreachable. Another significant difference between the two systems is that the addition of alcohol to 1A giving an alkoxo complex is endergonic by 8.1 kcal/mol, whereas the addition to 2A is exergonic by 8.9 kcal/mol. The thermodynamic difference could be the main reason for PNP-Ir system requiring lower catalyst loading than the PNN-Ru system. We discuss how the differences are resulted in terms of electronic and geometric structures of the catalysts and how to use the features in catalyst development. © 2014 American Chemical Society.

  12. Alternating copolymers of cyclopenta[2,1-b;3,4-b']dithiophene and Thieno[3,4-c]pyrrole-4,6-dione for high-performance polymer solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhao; Du, Xiaomei; Scoles, Ludmila; Robertson, Gilles; Toll, Floyd; Ding, Jianfu [Institute for Chemical Process and Environmental Technology (ICPET), National Research Council of Canada (NRC), Ottawa, ON (Canada); Tsang, Sai-Wing; Zhang, Yanguang; Tao, Ye; Lu, Jianping [Institute for Microstructural Sciences (IMS), National Research Council of Canada (NRC), Ottawa, ON (Canada)

    2011-09-09

    A series of alternating copolymers of cyclopenta[2,1-b;3,4-b']dithiophene (CPDT) and thieno[3,4-c]pyrrole-4,6-dione (TPD) have been prepared and characterized for polymer solar cell (PSC) applications. Different alkyl side chains, including butyl (Bu), hexyl (He), octyl (Oc), and 2-ethylhexyl (EH), are introduced to the TPD unit in order to adjust the packing of the polymer chain in the solid state, while the hexyl side chain on the CPDT unit remains unchanged to simplify discussion. The polymers in this series have a simple main chain structure and can be synthesized easily, have a narrow band gap and a broad light absorption. The different alkyl chains on the TPD unit not only significantly influence the solubility and chain packing, but also fine tune the energy levels of the polymers. The polymers with Oc or EH group have lower HOMO (highest occupied molecular orbital) and LUMO (lowest unoccupied molecular orbital) energy levels, resulting higher open circuit voltages (V{sub oc}) of the PSC devices. Power conversion efficiencies (PCEs) up to 5.5% and 6.4% are obtained from the devices of the Oc substituted polymer (PCPDTTPD-Oc) with PC{sub 61}BM and PC{sub 71}BM, respectively. This side chain effect on the PSC performance is related to the formation of a fine bulk heterojunction structure of polymer and PCBM domains, as observed with atomic force microscopy. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Synthesis, characterization and conductivity studies of polypyrrole–fly ash composites

    Indian Academy of Sciences (India)

    M V Murugendrappa; Syed Khasim; M V N Ambika Prasad

    2005-10-01

    in situ polymerization of pyrrole was carried out in the presence of fly ash (FA) to synthesize polypyrrole–fly ash composites (PPy/FA) by chemical oxidation method. The PPy/FA composites have been synthesized with various compositions (10, 20, 30, 40 and 50 wt%) of fly ash in pyrrole. The surface morphology of these composites was studied with scanning electron micrograph (SEM). The polypyrrole–fly ash composites were also characterized by employing X-ray diffractometry (XRD) and infrared spectroscopy (IR). The a.c. conductivity behaviour has been investigated in the frequency range 102–106 Hz. The d.c. conductivity was studied in the temperature range from 40–200°C. The dimensions of fly ash in the matrix have a greater influence on the observed conductivity values. The results obtained for these composites are of greater scientific and technological interest.

  14. Schiff base functionalized Organopropylsilatranes: Synthesis and structural characterization

    Indian Academy of Sciences (India)

    Gurjaspreet Singh; Promila; Amandeep Saroa; Jandeep Singh; Raj Pal Sharm; V Ferretti

    2016-02-01

    Synthesis of Schiff bases linked to organopropylsilatranes were performed by condensation reaction of post-functionalized silatranes such as aminopropylsilatrane (4), aminopropyl-3,7,10-trimethylsilatrane (5) and N-substituted aminopropylsilatrane (10) with two different aldehydes viz. pyrrole-2-carboxaldehyde and 2-hydroxy-1-napthaldehyde. The resulting Schiff base substituted silatranes were well characterized by elemental analysis, spectroscopic studies [IR, (1H, 13C) NMR, and MS]. The structures of two silatranes were confirmed by single crystal X-ray diffraction analysis.

  15. Cation Recognition: Novel Potentiometric PVC-Membrane Sensor based on Meso-octamethylcalix[4]pyrrole for the Determination of Trace Amounts of Titanium (III) Ions

    International Nuclear Information System (INIS)

    The present work deals with developing a novel high selective membrane electrode based on meso-octamethylcalix[4]pyrrole for accurate determination of trace amount of titanium (III) ions in real sample solutions. The amounts of ionophore (4 mg), PVC (33 mg), dioctyl phthalate (DOP) as plasticizer (62.8 mg) and sodium tetrakis [3,5-bis (trifluoromethyl) phenyl] borate (NaTFPB) as an ionic additive (0.2 mg) were optimized in the preparation of the membrane. The electrode exhibited a linear response with a near Nernstian slope of 29.49±0.16 (mV per decade of activity) over the pH range from 1 to 3 with a satisfactory concentration range of 1.0 x 10-6 to 1.0 x x10-2 M. The developed sensor exhibited good reproducibility over a period of about 3 months with a fast response time of 15 seconds. (author)

  16. Effects of Molecular Structure on Intramolecular Charge Carrier Transport in Dithieno [3,2-b: 2,3-d] Pyrrole-Based Conjugated Copolymers

    Directory of Open Access Journals (Sweden)

    Yoshihito Honsho

    2012-01-01

    Full Text Available Intramolecular mobility of positive charge carriers in conjugated polymer films based on dithieno [2,3-b: 2,3-d] pyrrole (DTP is studied by time-resolved microwave conductivity (TRMC. A series of DTP homopolymer and copolymers combined with phenyl, 2,2-biphenyl, thiophene, 2,2-bithiophene, and 9,9-dioctylfluorene were synthesized by Suzuki-Miyaura and Yamamoto coupling reactions. Polymers containing DTP unit are reported to show high value of hole mobility measured by FET method, and this type of polymers is expected to have stable HOMO orbitals which are important for hole transportation. Among these copolymers, DTP coupled with 9,9-dioctylfluorene copolymer showed the highest charge carrier mobility as high as 1.7 cm2/Vs, demonstrating an excellent electrical property on rigid copolymer backbones.

  17. Emission and absorption of light in poly pyrrole synthesized by plasma; Emision y absorcion de luz en polipirrol sintetizado por plasma

    Energy Technology Data Exchange (ETDEWEB)

    Enriquez, M.A.; Colin, E.; Olayo, M.G.; Cruz, G.J.; Ordonez, E. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Benavides, R. [Departamento de Procesos de Transformacion, CIQA, Blvd. Enrique Reyna 140, Saltillo, Coahuila (Mexico); Morales, J.; Olayo, R. [UAM-I, Apdo. Postal 55-534, Iztapalapa, D.F. (Mexico)]. e-mail: gcc@nuclear.inin.mx

    2007-07-01

    The poly pyrrole structure (PPy) consists of heterocyclic rings with conjugation that it depends on the intensity of the electric field applied during the synthesis, and its luminescence is related with the {pi}-{pi}{sup *} transitions of that conjugation. To irradiate with light of different wavelengths, the results indicate that the polymer absorbs in the interval from 290 to 700 nm and it emits between 450 and 470 nm. The basal conductivity of the polymers, without electromagnetic excitation, it was measured in 10{sup -15} S/cm, however, to interact with visible light it is increased approximately 10 times and when excite with UV light it is increased up to 3 magnitude orders. (Author)

  18. Discovery of 2-azetidinone and 1H-pyrrole-2,5-dione derivatives containing sulfonamide group at the side chain as potential cholesterol absorption inhibitors.

    Science.gov (United States)

    Yuan, Xinrui; Lu, Peng; Xue, Xiaojian; Qin, Hui; Fan, Chen; Wang, Yubin; Zhang, Qi

    2016-02-01

    Cholesterol absorption inhibitor (CAI) targeting Niemann-Pick C1-like1 protein was developed for the treatment of hyperlipidaemia and only ezetimibe was approved so far. For developing novel CAIs, we synthesized sixteen 2-azetidinone derivatives and thirteen 1H-pyrrole-2,5-dione derivatives containing sulfonamide group at the side chain, and their inhibitory activity of cholesterol absorption was evaluated in Caco-2 cell line in vitro. Furthermore, top six compounds were measured by cytotoxicity and partition coefficient, and 2-azetidinone analogue 9e was selected for in vivo study. Finally, 9e considerably reduced total cholesterol, LDL-C, FFA and triglyceride in the serum and increased the rate of HDL-C to total cholesterol, suggesting it could regulate the lipid metabolism and act as a potent CAI.

  19. Gamma irradiation effect on polymers derived of pyrrole synthesized by plasma; Efecto de irradiacion gamma en polimeros derivados de pirrol sintetizados por plasma

    Energy Technology Data Exchange (ETDEWEB)

    Lopez G, O. G.

    2013-07-01

    This work studies the effect of gamma irradiation at doses of 50, 100, 200, 400 and 800 kGy on polymers obtained from pyrrole synthesized by plasma. The evolution of the structure was studied by Fourier transform infrared spectroscopy (Ftir) and X-ray photoelectron spectroscopy (XPS). The Ftir spectra show that poly pyrroles have N-H, C-H, C=O, triple and consecutive double bonds in their structure. The irradiated polymers show the same chemical groups in their structure without significant changes. Nevertheless, a more detailed analysis by XPS allows the identification of superficial chemical states, such as: C=CH-C, C=CC-C, C-NH-C, C-NC-C, etc., and shows that most of these states are present in all polymers but with different participation. One possible mechanism indicates that as the irradiation dose increases, dehydrogenation processes are performed increasing fragmentation, crosslinking and formation of multiple bonds. The fragmentation and thermal degradation were studied by thermogravimetric analysis, indicating that the loss of moisture and light compounds formed during gamma irradiation occurs in the firsts 100 grades C. The main degradation of all polymers occurs from 150 to 700 grades C, suggesting that the thermal stability is independent of the irradiation dose in the interval studied. Morphology was studied using scanning electron microscopy techniques. Before irradiation, the polymer presented a uniform and practically smooth surface, however, after gamma irradiation, the applied energy increased roughness and macro fragmentation. The roughness and functional groups on the surface reduced the contact angle with water as the irradiation dose increased. However, the polymers are hydrophilic, because for all doses that contact angle is smaller than 90 grades C. Electrical conductivity was calculated respect to temperature in the interval from 25 to 100 grades C. Conductivity increases with temperature and is slightly greater in the irradiated polymers

  20. 1-Aryl-5-(1H-pyrrol-1-yl)-1H-pyrazole-3-carboxamide: an effective scaffold for the design of either CB1 or CB2 receptor ligands.

    Science.gov (United States)

    Piscitelli, Francesco; Ligresti, Alessia; La Regina, Giuseppe; Gatti, Valerio; Brizzi, Antonella; Pasquini, Serena; Allarà, Marco; Carai, Mauro Antonio Maria; Novellino, Ettore; Colombo, Giancarlo; Di Marzo, Vincenzo; Corelli, Federico; Silvestri, Romano

    2011-11-01

    New 1-aryl-5-(1H-pyrrol-1-yl)-1H-pyrazole-3-carboxamides were synthesized as cannabinoid (CB) receptor ligands. Compound 11 (CB(1)K(i) = 2.3 nM, CB(1) SI = 163.6) showed CB(1) receptor affinity and selectivity superior to Rimonabant and AM251. Acute administration of 2mg/kg 11 reduced sucrose, but not regular food, intake in rats. On the other hand, compound 23 (CB(2)K(i) = 0.51 nM, CB(2) SI = 30.0) showed significant affinity and selectivity for the CB(2) receptor. The results presented here show that the 1-aryl-5-(1H-pyrrol-1-yl)-1H-pyrazole-3-carboxamide may serve as an effective scaffold for the design of either CB(1) or CB(2) receptor ligands. PMID:21996466

  1. Biocatalytic ammonolysis of (5S)-4,5-dihydro-1H-pyrrole-1,5-dicarboxylic acid, 1-(1,1-dimethylethyl)-5-ethyl ester: preparation of an intermediate to the dipeptidyl peptidase IV inhibitor Saxagliptin.

    Science.gov (United States)

    Gill, Iqbal; Patel, Ramesh

    2006-02-01

    An efficient biocatalytic method has been developed for the conversion of (5S)-4,5-dihydro-1H-pyrrole-1,5-dicarboxylic acid, 1-(1,1-dimethylethyl)-5-ethyl ester (1) into the corresponding amide (5S)-5-aminocarbonyl-4,5-dihydro-1H-pyrrole-1-carboxylic acid, 1-(1,1-dimethylethyl)ester (2), which is a critical intermediate in the synthesis of the dipeptidyl peptidase IV (DPP4) inhibitor Saxagliptin (3). Candida antartica lipase B mediates ammonolysis of the ester with ammonium carbamate as ammonia donor to yield up to 71% of the amide. The inclusion of Ascarite and calcium chloride as adsorbents for carbon dioxide and ethanol byproducts, respectively, increases the yield to 98%, thereby offering an efficient and practical alternative to chemical routes which yield 57-64%.

  2. 4-Hydroxy-7-oxo-5-heptenoic Acid (HOHA) Lactone is a Biologically Active Precursor for the Generation of 2-(ω-Carboxyethyl)pyrrole (CEP) Derivatives of Proteins and Ethanolamine Phospholipids

    OpenAIRE

    Hua WANG; Linetsky, Mikhail; Guo, Junhong; Choi, Jaewoo; Hong, Li; Chamberlain, Amanda S.; Howell, Scott J.; Howes, Andrew M.; Robert G Salomon

    2015-01-01

    2-(ω-Carboxyethyl)pyrrole (CEP) derivatives of proteins were previously shown to have significant pathological and physiological relevance to age-related macular degeneration, cancer and wound healing. Previously, we showed that CEPs are generated in the reaction of ε-amino groups of protein lysyl residues with 1-palmityl-2-(4-hydroxy-7-oxo-5-heptenoyl)-sn-glycero-3-phosphatidylcholine (HOHA-PC), a lipid oxidation product uniquely generated by oxidative truncation of doco...

  3. Thieno[3,2-b]- and thieno[2,3-b]pyrrole bioisosteric analogues of the hallucinogen and serotonin agonist N,N-dimethyltryptamine.

    Science.gov (United States)

    Blair, J B; Marona-Lewicka, D; Kanthasamy, A; Lucaites, V L; Nelson, D L; Nichols, D E

    1999-03-25

    The synthesis and biological activity of 6-[2-(N, N-dimethylamino)ethyl]-4H-thieno[3,2-b]pyrrole (3a) and 4-[2-(N, N-dimethylamino)ethyl]-6H-thieno[2,3-b]pyrrole (3b), thienopyrroles as potential bioisosteres of N,N-dimethyltryptamine (1a), are reported. Hallucinogen-like activity was evaluated in the two-lever drug discrimination paradigm using LSD- and DOI-trained rats. Neither 3a nor 3b substituted for LSD or DOI up to doses of 50 micromol/kg. By comparison, 1a fully substituted in LSD-trained rats. However, 3a and 3b fully substituted for the 5-HT1A agonist LY293284 ((-)-(4R)-6-acetyl-4-(di-n-propylamino)-1,3,4, 5-tetrahydrobenz[c,d]indole). Both 3a and 3b induced a brief "serotonin syndrome" and salivation, an indication of 5-HT1A receptor activation. At the cloned human 5-HT2A receptor 3b had about twice the affinity of 3a. At the cloned human 5-HT2B and 5-HT2C receptors, however, 3a had about twice the affinity of 3b. Therefore, thiophene lacks equivalence as a replacement for the phenyl ring in the indole nucleus of tryptamines that bind to 5-HT2 receptor subtypes and possess LSD-like behavioral effects. Whereas both of the thienopyrroles had lower affinity than the corresponding 1a at 5-HT2 receptors, 3a and 3b had significantly greater affinity than 1a at the 5-HT1A receptor. Thus, thienopyrrole does appear to serve as a potent bioisostere for the indole nucleus in compounds that bind to the serotonin 5-HT1A receptor. These differences in biological activity suggest that serotonin receptor isoforms are very sensitive to subtle changes in the electronic character of the aromatic systems of indole compounds. PMID:10090793

  4. Scientific Opinion on Flavouring Group Evaluation 77, Revision 1 (FGE.77Rev1: Consideration of Pyridine, Pyrrole and Quinoline Derivatives evaluated by JECFA (63rd meeting structurally related to Pyridine, Pyrrole, Indole and Quinoline Derivatives evaluated by EFSA in FGE.24Rev2 (2013

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids (CEF

    2014-02-01

    Full Text Available The Panel on Food Contact Materials, Enzymes, Flavourings and Processing Aids of the European Food Safety Authority was requested to consider evaluations of flavouring substances assessed since 2000 by the Joint FAO/WHO Expert Committee on Food Additives (the JECFA, and to decide whether further evaluation is necessary, as laid down in Commission Regulation (EC No 1565/2000. The present consideration concerns a group of 22 pyridine, pyrrole and quinoline derivatives evaluated by the JECFA (63rd meeting. The revision of this consideration is made since additional toxicity data have become available for isoquinoline [FL-no: 14.001], pyrrole [FL-no: 14.041] and 2-acetylpyrrole [FL-no: 14.047]. The toxicity data on 2-acetylpyrrole should also cover 2-propionylpyrrole [FL-no: 14.068]. Further, additional genotoxicity data on 6-methylquinoline [FL-no: 14.042] have become available. The Panel concluded that for 6-methylquinoline [FL-no: 14.042], the new genotoxicity data did not clear the concern with respect to genotoxicity in vitro and accordingly the substance is not evaluated through the Procedure. For 18 substances [FL-no: 14.001, 14.004, 14.007, 14.030, 14.038, 14.039, 14.041, 14.047, 14.058, 14.059, 14.060, 14.061, 14.065, 14.066, 14.068, 14.071, 14.072 and 14.164] considered in this FGE, the Panel agrees with the JECFA conclusion, “No safety concern at estimated levels of intake as flavouring substances” based on the MSDI approach. For three substances [FL-no: 13.134, 14.045 and 14.046], additional toxicological data are still required. Besides the safety assessment of these flavouring substances, the specifications for the materials of commerce have also been evaluated, and the information is considered adequate for all the substances.

  5. Dendrimer Templated Synthesis of One Nanometer Rh and Pt Particles Supported on Mesoporous Silica: Catalytic Activity for Ethylene and Pyrrole Hydrogenation.

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Wenyu; Kuhn, John N.; Tsung, Chia-Kuang; Zhang, Yawen; Habas, Susan E.; Yang, Peidong; Somorjai, Gabor A.

    2008-05-09

    Monodisperse rhodium (Rh) and platinum (Pt) nanoparticles as small as {approx}1 nm were synthesized within a fourth generation polyaminoamide (PAMAM) dendrimer, a hyperbranched polymer, in aqueous solution and immobilized by depositing onto a high-surface-area SBA-15 mesoporous support. X-ray photoelectron spectroscopy indicated that the as-synthesized Rh and Pt nanoparticles were mostly oxidized. Catalytic activity of the SBA-15 supported Rh and Pt nanoparticles was studied with ethylene hydrogenation at 273 and 293 K in 10 torr of ethylene and 100 torr of H{sub 2} after reduction (76 torr of H{sub 2} mixed with 690 torr of He) at different temperatures. Catalysts were active without removing the dendrimer capping but reached their highest activity after hydrogen reduction at a moderate temperature (423 K). When treated at a higher temperature (473, 573, and 673 K) in hydrogen, catalytic activity decreased. By using the same treatment that led to maximum ethylene hydrogenation activity, catalytic activity was also evaluated for pyrrole hydrogenation.

  6. Comparative Analysis of DNA-Binding Selectivity of Hairpin and Cyclic Pyrrole-Imidazole Polyamides Based on Next-Generation Sequencing.

    Science.gov (United States)

    Kashiwazaki, Gengo; Chandran, Anandhakumar; Asamitsu, Sefan; Kawase, Takashi; Kawamoto, Yusuke; Sawatani, Yoshito; Hashiya, Kaori; Bando, Toshikazu; Sugiyama, Hiroshi

    2016-09-15

    Many long pyrrole-imidazole polyamides (PIPs) have been synthesized in the search for higher specificity, with the aim of realizing the great potential of such compounds in biological and clinical areas. Among several types of PIPs, we designed and synthesized hairpin and cyclic PIPs targeting identical sequences. Bind-n-Seq analysis revealed that both bound to the intended sequences. However, adenines in the data analyzed by the previously reported Bind-n-Seq method appeared to be significantly higher in the motif ratio than thymines, even though the PIPs were not expected to distinguish A from T. We therefore examined the experimental protocol and analysis pipeline in detail and developed a new method based on Bind-n-Seq motif identification with a reference sequence (Bind-n-Seq-MR). High-throughput sequence analysis of the PIP-enriched DNA data by Bind-n-Seq-MR presented A and T comparably. Surface plasmon resonance assays were performed to validate the new method. PMID:27387250

  7. Synthesis, characterisation and electrical properties of supramolecular DNA-templated polymer nanowires of 2,5-(bis-2-thienyl)-pyrrole.

    Science.gov (United States)

    Watson, Scott M D; Hedley, Joseph H; Galindo, Miguel A; Al-Said, Said A F; Wright, Nick G; Connolly, Bernard A; Horrocks, Benjamin R; Houlton, Andrew

    2012-09-17

    Supramolecular polymer nanowires have been prepared by using DNA-templating of 2,5-(bis-2-thienyl)-pyrrole (TPT) by oxidation with FeCl(3) in a mixed aqueous/organic solvent system. Despite the reduced capacity for strong hydrogen bonding in polyTPT compared to other systems, such as polypyrrole, the templating proceeds well. FTIR spectroscopic studies confirm that the resulting material is not a simple mixture and that the two types of polymer interact. This is indicated by shifts in bands associated with both the phosphodiester backbone and the nucleobases. XPS studies further confirm the presence of DNA and TPT, as well as dopant Cl(-) ions. Molecular dynamics simulations on a [{dA(24):dT(24)}/{TPT}(4)] model support these findings and indicate a non-coplanar conformation for oligoTPT over much of the trajectory. AFM studies show that the resulting nanowires typically lie in the 7-8 nm diameter range and exhibit a smooth, continuous, morphology. Studies on the electrical properties of the prepared nanowires by using a combination of scanned conductance microscopy, conductive AFM and variable temperature two-terminal I-V measurements show, that in contrast to similar DNA/polymer systems, the conductivity is markedly reduced compared to bulk material. The temperature dependence of the conductivity shows a simple Arrhenius behaviour consistent with the hopping models developed for redox polymers.

  8. Self-doped anthranilic acid-pyrrole copolymer/gold electrodes for selective preconcentration and determination of Cu(I) by differential pulse anodic stripping voltammetry.

    Science.gov (United States)

    Nateghi, M R; Fallahian, M H

    2007-05-01

    Electropolymerization of anthranilic acid/pyrrole (AA/PY) at solid substrate electrodes (platinum, gold, and glassy carbon) gave stable and water-insoluble films under a wide range of pH. Combining high conductivity of the polypyrrole (PPY) and pH independence of the electrochemical activity of the self-doped carboxylic acid-substituted polyaniline allows us to prepare an improved functionalized PPY-modified electrode to collect and measure Cu(I) species. The differential pulse stripping analysis of the copper ions using a polyanthranilic acid-co-polypyrrole (PAA/PPY)-modified electrode consisted of three steps: accumulation, electrochemical reduction to the elemental copper and stripping step. Factors affecting these steps, including electropolymerization conditions, accumulation and stripping medium, reduction potential, reduction time and accumulation time, were systematically investigated. A detection limit of 5.3 x 10(-9) M Cu(I) was achieved for a 7.0 min accumulation. For 12 determinations of Cu(I) at concentrations of 1.0 x 10(-8) M, an RSD of 3.5% was obtained. The log I(p) was found to vary linearly with log[Cu(I)] in the concentration range from 7.0 x 10(-9) to 1.0 x 10(-5) M.

  9. Fe nanoparticle tailored poly(N-methyl pyrrole) nanowire matrix: a CHEMFET study from the perspective of discrimination among electron donating analytes

    International Nuclear Information System (INIS)

    Back-gated chemically sensitive field effect transistor (CHEMFET) platforms have been developed with electrochemically synthesized poly(N-methyl pyrrole) nanowires by a templateless route. The nanowire matrix has been tailored with Fe nanoparticles to probe their effect in enhancing the sensing capabilities of the nanowire platform, and further to see if the inculcation of Fe nanoparticles is helpful to enhance the screening capability of the sensor among electron donating analytes. A noticeable difference in the sensing behaviour of the CHEMFET sensor was observed when it was exposed to three different analytes—ammonia, phosphine and carbon monoxide. FET transfer characteristics were instrumental in the corroboration of the experimental validations. The observations have been rationalized considering the simultaneous modulation of the work functions of Fe and polymeric material. The real time behaviour of the sensor shows that the sensor platform is readily capable of sensing the validated analytes at a ppb level of concentration with good response and recovery behaviour. The best response could be observed for ammonia with an Fe nanoparticle tailored polymeric matrix, with a sensitivity of ∼31.58% and excellent linearity (R2 = 0.985) in a concentration window of 0.05 ppm to 1 ppm. (paper)

  10. Photocatalytic Degradation of Eosin Yellow Using Poly(pyrrole-co-aniline-Coated TiO2/Nanocellulose Composite under Solar Light Irradiation

    Directory of Open Access Journals (Sweden)

    T. S. Anirudhan

    2015-01-01

    Full Text Available The present study describes the feasibility of a novel adsorbent cum photocatalyst, poly(pyrrole-co-aniline-coated TiO2/nanocellulose composite (P(Py-co-An-TiO2/NCC, to remove eosin yellow (EY from aqueous solutions. The removal of EY was investigated by batch adsorption followed by photocatalysis. The effect of various adsorption parameters like adsorbent dose, pH, contact time, initial concentration, and ionic strength has been optimized for treating effluents from the dye industry. Adsorption of EY reached maximum at pH 4.5 and complete removal of dye was achieved using 3.5 g/L of P(Py-co-An-TiO2/NCC. Adsorption equilibrium data were fitted with Langmuir and Fritz-Schlunder isotherm models and the kinetics of adsorption follows a second-order mechanism. The adsorption capacity of P(Py-co-An-TiO2/NCC was found to be 3.39 × 10−5 mol/g and reached equilibrium within 90 min. The photocatalytic degradation of adsorbed dye under sunlight was possible and about 92.3% of dye was degraded within 90 min. The reusability of P(Py-co-An-TiO2/NCC was also investigated. The results indicate that P(Py-co-An-TiO2/NCC is the best material for the wiping out of EY from aqueous solutions.

  11. ToF-SIMS Characterization of Silk Fibroin and Polypyrrole Composite Actuators

    Energy Technology Data Exchange (ETDEWEB)

    Bradshaw, Nathan P.; Severt, Sean Y.; Wang, Zhaoying; Fengel, Carly V.; Larson, Jesse D.; Zhu, Zihua; Murphy, Amanda; Leger, Janelle M.

    2015-08-31

    Biocompatible materials capable of controlled actuation under biologically relevant conditions are in high demand for use in a number of biomedical applications. Recently, we demonstrated that a composite material composed of silk biopolymer and the conducting polymer poly(pyrrole) can bend under an applied voltage using a simple bilayer device. Here we present further characterization of these bilayer actuators using time of flight secondary ion mass spectrometry, and provide clarification on the mechanism of actuation and factors affecting device performance and stability. We will discuss the results of this study in the context of strategies for optimization of device performance.

  12. Controlling pyridinic, pyrrolic, graphitic, and molecular nitrogen in multi-wall carbon nanotubes using precursors with different N/C ratios in aerosol assisted chemical vapor deposition.

    Science.gov (United States)

    Bulusheva, L G; Okotrub, A V; Fedoseeva, Yu V; Kurenya, A G; Asanov, I P; Vilkov, O Y; Koós, A A; Grobert, N

    2015-10-01

    Nitrogen-containing multi-wall carbon nanotubes (N-MWCNTs) were synthesized using aerosol assisted chemical vapor deposition (CVD) techniques in conjunction with benzylamine:ferrocene or acetonitrile:ferrocene mixtures. Different amounts of toluene were added to these mixtures in order to change the N/C ratio of the feedstock. X-ray photoelectron and near-edge X-ray absorption fine structure spectroscopy detected pyridinic, pyrrolic, graphitic, and molecular nitrogen forms in the N-MWCNT samples. Analysis of the spectral data indicated that whilst the nature of the nitrogen-containing precursor has little effect on the concentrations of the different forms of nitrogen in N-MWCNTs, the N/C ratio in the feedstock appeared to be the determining factor. When the N/C ratio was lower than ca. 0.01, all four forms existed in equal concentrations, for N/C ratios above 0.01, graphitic and molecular nitrogen were dominant. Furthermore, higher concentrations of pyridinic nitrogen in the outer shells and N2 molecules in the core of the as-produced N-MWCNTs suggest that the precursors were decomposed into individual atoms, which interacted with the catalyst surface to form CN and NH species or in fact diffused through the bulk of the catalyst particles. These findings are important for a better understanding of possible growth mechanisms for heteroatom-containing carbon nanotubes (CNTs) and therefore paving the way for controlling the spatial distribution of foreign elements in the CNTs using CVD processes. PMID:26104737

  13. Marked Consequences of Systematic Oligothiophene Catenation in Thieno[3,4-c]pyrrole-4,6-dione and Bithiopheneimide Photovoltaic Copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Nanjia; Guo, Xugang; Ponce Ortiz, Rocio; Harschneck, Tobias; Manley, Eric F.; Lou, Sylvia J.; Hartnett, Patrick E.; Yu, Xinge; Horwitz, Noah E.; Mayorga Burrezo, Paula; Aldrich, Thomas J.; Lopez Navarrete, Juan T.; Wasielewski, Michael R.; Chen, Lin X.; Chang, Robert P. H.; Facchetti, Antonio; Marks, Tobin J.

    2015-10-07

    As effective building blocks for high-mobility transistor polymers, oligothiophenes are receiving attention for polymer solar cells (PSCs) because the resulting polymers can effectively suppress charge recombination. Here we investigate two series of in-chain donor-acceptor copolymers, PTPDnT and PBTInT, based on thieno[3,4-c]pyrrole-4,6-dione (TPD) or bithiopheneimide (BTI) as electron acceptor units, respectively, and oligothiophenes (nTs) as donor counits, for high-performance PSCs. Intramolecular S···O interaction leads to more planar TPD polymer backbones, however backbone torsion yields greater open-circuit voltages for BTI polymers. Thiophene addition progressively raises polymer HOMOs but marginally affects their band gaps. FT-Raman spectra indicate that PTPDnT and PBTInT conjugation lengths scale with nT catenation up to n = 3 and then saturate for longer oligomer. Furthermore, the effects of oligothiophene alkylation position are explored, revealing that the alkylation pattern greatly affects film morphology and PSC performance. The 3T with “outward” alkylation in PTPD3T and PBTI3T affords optimal π-conjugation, close stacking, long-range order, and high hole mobilities (0.1 cm2/(V s)). These characteristics contribute to the exceptional ~80% fill factors for PTPD3T-based PSCs with PCE = 7.7%. The results demonstrate that 3T is the optimal donor unit among nTs (n = 1-4) for photovoltaic polymers. Grazing incidence wide-angle X-ray scattering, transmission electron microscopy, and time-resolved microwave conductivity measurements reveal that the terthiophene-based PTPD3T blend maintains high crystallinity with appreciable local mobility and long charge carrier lifetime. These results provide fundamental materials structure-device performance correlations and suggest guidelines for designing oligothiophene-based polymers with optimal thiophene catenation and appropriate alkylation pattern to maximize PSC performance.

  14. Synthesis and Properties of Heteroacenes Containing Pyrrole and Thiazine Rings as Promising n-Type Organic Semiconductor Candidates

    Institute of Scientific and Technical Information of China (English)

    HONG,Wei; WEI,Zhongming; XU,Wei; WANG,Quanrui; ZHU,Daoben

    2009-01-01

    PBBTZ (6H-pyrrolo[3,2-b:4,5-b']bis[1,4]benzothiazine) was a p-type semiconductor with high field-effect transistor (FET) performance that we have just reported.Two trifluoromethyl substituted PBBTZ derivatives 3a and 3b were synthesized from facile one-pot condensation.They were characterized by means of 1H NMR,IR,HRMS (EI-TOF) and elemental analysis,furthermore,the crystal structure of 3b was described and discussed.Their optical properties were studied by UV-Vis and fluorescence spectroscopy,electrochemical properties were investigated by cyclic voltammetry (CV),and thermal properties were evaluated by thermal gravimetric analysis (TGA).The energy gaps of 3a and 3b,taken directly from spectroscopic measurements,are as broad as 2.45 and 2.48 eV,leading to bluish green and green photoluminescence.The LUMO and HOMO energy levels are -5.73 and -3.28 eV for 3a,-5.67 and -3.19 eV for 3b,respectively.The low energy levels render them well air-stable,and to be promising n-type semiconductor candidates for use in organic electronics.

  15. Ordering effects in benzo[1,2-b:4,5-b']difuran-thieno[3,4-c]pyrrole-4,6- dione polymers with >7% solar cell efficiency

    KAUST Repository

    Warnan, Julien

    2014-05-15

    Benzo[1,2-b:4,5-b\\']difuran-thieno[3,4-c]pyrrole-4,6-dione (PBDFTPD) polymers prepared by microwave-assisted synthesis can achieve power conversion efficiencies (PCEs) >7% in bulk-heterojunction solar cells with phenyl-C61/71-butyric acid methyl ester (PCBM). In "as-cast" PBDFTPD-based devices solution-processed without a small-molecule additive, high PCEs can be obtained in spite of the weak propensity of the polymers to self-assemble and form π-aggregates in thin films. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Property-based design and synthesis of new chloroquine hybrids via simple incorporation of 2-imino-thiazolidine-4-one or 1h-pyrrol-2, 5-dione fragments on the 4-amino-7-chloroquinoline side chain

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, Fernando A.; Kouznetsov, Vladimir V., E-mail: kouznet@uis.edu.co [Laboratorio de Quimica Organica y Biomolecular, Escuela de Quimica, Universidad Industrial de Santander, Bucaramanga (Colombia)

    2011-09-15

    In the present work, the syntheses of new 4-amino-7-chloroquinoline N-derivatives were performed by selective modification of the side chain amino group of N-(7-chloroquinoline-4-yl) alkyldiamines, basis framework of chloroquine (CQ) drug through the incorporation of heterocyclic 2-imino-thiazolidine-4-one and {sup 1}H-pyrrol-2,5-dione systems. These potential activity modulators were selected thanks to their characteristic properties, and evaluated by virtual screening employing the OSIRIS and Molinspirations platforms. Designed and synthesized quinolinic derivatives could increase the antimalarial activity of CQ analogues without affecting the lipophilicity as described in literature, suggesting them as candidates for further biological assessments. (author)

  17. Crystal structure of diethyl 2,2′-[((1E,1′E-{[(1R,4R-cyclohexane-1,4-diyl]bis(azanylylidene}bis(methanylylidenebis(1H-pyrrole-2,1-diyl]diacetate

    Directory of Open Access Journals (Sweden)

    Jasim Alshawi

    2015-03-01

    Full Text Available The whole molecule of the title compound, C24H32N4O4, is generated by inversion symmetry. The cyclohexane ring adopts a chair conformation and the conformation about the C=N bonds is E. The pyrrole rings have an anti confirmation with respect to the cyclohexane moiety and the ethyl acetate groups have extended conformations. In the crystal, molecules are linked by pairs of C—H...O hydrogen bonds forming chains, enclosing R22(10 ring motifs with inversion symmetry, propagating parallel to the (101 plane.

  18. Crystal structure of ethyl 2-(2-{1-[N-(4-bromophenyl)-2-oxo-2-phenylacetamido]-2-tert-butylamino-2-oxoethyl}-1H-pyrrol-1-yl)acetate

    OpenAIRE

    Tetsuji Moriguchi; Venkataprasad Jalli; Suvratha Krishnamurthy; Akihiko Tsuge; Kenji Yoza

    2015-01-01

    In the title compound, C28H30BrN3O5, there is an intramolecular N—H...O hydrogen bond and an intramolecular C—H...O hydrogen bond, both forming S(9) ring motifs. The planes of the 4-bromophenyl ring and the phenyl ring are inclined to that of the pyrrole ring by 48.05 (12) and 77.45 (14)°, respectively, and to one another by 56.25 (12)°. In the crystal, molecules are linked via C—H...O hydrogen bonds and C—H...π interactions, forming slabs parallel to (10-1).

  19. 3-substituted and 1, 3-disubstituted pyrroles synthesis from {alpha}, {beta} insaturated Nitriles. Formal total synthesis of Danaidona; Sintesis de pirroles 3-sustituidos y 1, 3-disustituidos a partir de Nitrilos {alpha}, {beta}- insaturados. Sintesis total formal de la Danaidona

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Hector; Flores, Blas; Leon, Fernando; Mendez, Jose Manuel [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

    1996-02-01

    We describe a short method to obtain 3-substituted and 1, 3-disubstituted pyrroles from {alpha}, {beta}-insaturated nitriles. We obtained the corresponding substituted succinonitriles from 1, 4-addition of hydrogen cyanide to {alpha}, {beta}-insaturated nitriles. [Spanish] Se describe un metodo corto para obtener pirroles 3-sustituidos y 1, 3-disustituidos a partir de nitrilos {alpha}, {beta}-insaturados. Se obtuvieron los correspondientes succinonitrilos sustituidos a partir de la adicion 1, 4 de acido cianhidrico a nitrilos {alpha}, {beta}-insaturados.

  20. Investigations on Electrochemical Copolymerization of Pyrrole and o-Phenetidine%吡咯与邻乙氧基苯胺电化学共聚研究

    Institute of Scientific and Technical Information of China (English)

    郑超; 吴晓军; 蔡然; 袁杰; 陈润锋; 戴郁菁; 黄维

    2011-01-01

    Pyrrole ( PY) and o-phenetidine ( OPT) electrochemical copolymerizations in aqueous acidic medium and organic solution with various monomer feed ratios have been investigated. UV-vis spectra indicate that the copolymers were obtained. The elementary analysis and cyclic voltammetry measurements reveal that the composition and electroactivities of the copolymers are affected by the different methods of polymerizations, media, and reaction conditions. It is found that a four-step process occurred during the potentiaostatic electrochemical copolymerization in 0. 3 M IiC104 acetonitrile solution,and the copolymer deposition mechanism is very close to 2D model. Whislt in 1 M H2SO4 aqueous solution,the progress is close to 2DI model in the early period,and then becomes a combination of 2DI and 3DI models. The po-tentiostatic electropolymerization of PY and OPT in the acidic aqueous medium below the 0. 7 V ( SCE ) potential,is more efficient to get electrochemical conducting polymers with high electroactivities.%研究了吡咯和邻乙氧基苯胺在水相和有机相中的恒电位化学共聚行为,通过紫外吸收光谱、元素分析和循环伏安测试表征了所得共聚物的组成、电活性及其受电聚合条件的影响,发现在乙腈溶液中,恒电压共聚存在4个阶段,电沉积以2D模式进行;而在水溶液中,电沉积在早期是按2DI模式,后期介于2DI和3DI之间.制备规整的、具有较高电活性的吡咯和邻乙氧基苯胺导电聚合物薄膜,需在酸性水溶液中进行,以聚合电压小于0.7V的恒电位聚合条件最为理想.

  1. Structure Sensitivity of Carbon-Nitrogen Ring Opening: Impact of Platinum Particle Size from below 1 to 5 nm upon Pyrrole Hydrogenation Product Selectivity over Monodisperse Platinum Nanoparticles Loaded onto Mesoporous Silica

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, John N.; Huang, Wenyu; Tsung, Chia-Kuang; Zhang, Yawen; Somorjai, Gabor A.

    2008-07-01

    The ability to control fundamental properties (e.g., particle size, surface structure, and metal-oxide interface) in order to design highly selective heterogeneous catalysts would greatly reduce energy intensive separations. Particle size dependence (i.e., structure sensitivity) upon selectivity can now be examined with well defined nanoparticles (NPs) because of advances in synthetic chemistry. Colloidal chemistry has provided means for synthesizing monodisperse Pt NPs as small as {approx}2 nm. Using a dendrimer templated approach, Pt NPs smaller than 1 nm--a new size regime for studying size induced effects in heterogeneous catalysis--can be synthesized (Scheme 1). In this contribution, we report that ring opening for pyrrole hydrogenation is distinctly different for Pt NPs smaller than 2 nm. This insight has not been demonstrated for hydrogenation of cyclic heteroatom bonds to the best of our knowledge. This finding adds fundamental insight into hydrodenitrogenation (HDN) chemistry, which is important for fuel processing and involves removal of N-containing organics. Advances in HDN catalysis are needed to meet new fuel quality regulations because N-containing organics inhibit hydrodesulfurization (HDS) through competitive adsorption and poison acid catalysts, which are used for downstream processing and as supports for HDS catalysts. Pyrrole was selected as the reactant because organics with 5-member N-containing rings are the most common components in fuel.

  2. (3′R-3′-Benzyl-2′,3′-dihydro-1H-spiro[indole-3,1′-naphtho[2,3-c]pyrrole]-2,4′,9′-trione

    Directory of Open Access Journals (Sweden)

    Garima Sharma

    2012-09-01

    Full Text Available In the title compound, C26H18N2O3, the maximum deviations from planarity for the tetrahydro-1H-naphtho[2,3-c]pyrrole and indoline rings systems are 0.091 (1 and 0.012 (2 Å, respectively. These ring systems make a dihedral angle of 89.95 (6° with each other and they make dihedral angles of 73.42 (8 and 71.28 (9°, respectively, with the benzene ring. In the crystal, inversion dimers linked by pairs of N—H...O hydrogen bonds generate R22(8 loops and C—H...O interactions connect the dimers into corrugated sheets lying parallel to the bc plane.

  3. Theoretical study of photophysical properties of 1,4-dihydropyrrolo[3,2-b]pyrrole-cored branched molecules with thienylenevinylene arms toward broad absorption spectra for solar cells.

    Science.gov (United States)

    Tang, Shanshan; Tang, Binbin; Liang, Dadong; Chen, Guang; Jin, Ruifa

    2013-09-01

    A series of oligo(thienylenevinylene) derivatives with 1,4-dihydropyrrolo[3,2-b]pyrrole as core has been investigated at the PBE0/6-31G(d) and the TD-PBE0/6-31+G(d,p) levels to design materials with high performances such as broad absorption spectra and higher balance transfer property. The results show that position and amount of arm affect the electronic density contours of frontier molecular orbitals significantly. The molecule with four arms owns the narrowest energy gap and the largest maximum absorption wavelength, and the molecule with two arms in positions a and c has the broadest absorption region among the designed molecules. Calculated reorganization energies of the designed molecules indicate that the molecules with two arms can be good potential ambipolar transport materials under proper operating conditions.

  4. A Novel Photocleaver with Long Wavelength Absorption-Highly Efficient Antitumor Agent:4-(2-Diethylamino-ethylamino)-8-oxo-8H-acenaphtho-[1,2-b]pyrrole-9-carbonitrile

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-chao; L(U¨) Zhe; QIAN Xu-hong; LIU Feng-yu; SHENG Hui

    2005-01-01

    The photocleavage abilities of a novel family of compounds, 8-oxo-8 H -acenaphtho[1,2-b] pyrrole-9-carbonitrile and its derivatives(compounds 1-5) were evaluated with M13 mp18 single strand circular DNA. Only compound 1 with a diethylamine group could bind to DNA via electrostatic attraction and intercalation. At a concentration of 50 μmol/L, it could generate singlet oxygen to cleave circular DNA into linear DNA under the irradiation of long wavelength light(λ>400 nm). The antitumor ability of compound 1 was also evaluated in vitro, and its IC50 on HeLa cells was as low as 6.8 μmol/L.

  5. 1,8-二(2-吡咯酰胺)-3,6-二氯咔唑的合成、晶体结构及阴离子识别研究%Synthesis, Crystal Structure and Anion Recognition of 1,8-Di(pyrrole-2-carboxamino)-3,6-dichlorocarbazole

    Institute of Scientific and Technical Information of China (English)

    苏冬冬; 牛浩涛; 王莹; 何家骐; 程津培

    2009-01-01

    设计并合成了1,8-二(2-吡咯酰胺)-3,6-二氯咔唑化合物(1), 利用X射线单晶衍射研究了该化合物的固态结构. 利用荧光和紫外-可见光谱技术及 1H NMR滴定法研究了其对阴离子的识别. 研究结果表明, 化合物1对H_2PO~-_4离子有较强的识别能力, 且对H_2PO~-_4离子有明显的荧光增强效应, 可用来识别H_2PO~-_4离子. 同时~1H NMR滴定结果显示, 化合物1在阴离子识别过程中发生了构型转化.%Due to the fundamental roles that anions play in a wide range of chemical and biological processes, numerous efforts have been devoted to the design of receptors capable of selectively binding and sensing anions. Herein, carbazole derivative (1) bearing two model amides was synthesized by coupling 1,8-diamino-3 ,6-dichlorocarbazole with pyrrole-2-carbonylchloride in the presence of triethylamine. The structure of compound 1 was characterized by X-ray crystallography. The anions recognition of the compound 1 was studied by the UV-Vis and fluorescent spectra method in highly polar solvent of DMSO. The results show that strong anion binding is observed for H_2PO_4~-. Obvious fluorescence "switched on" behavior is observed upon addition of H_2PO_4~- to receptor 1, which can be used to discriminate H_2PO_4~- from the other anions. 'H NMR analysis revealed that all the five NH of receptor 1 were involved in the hydrogen bonding interactions with the anions leading to a conformation exchange during the anion binding.

  6. Synthesis of novel 5-alkyl/aryl/heteroaryl substituted diethyl 3,4-dihydro-2H-pyrrole-4,4-dicarboxylates by aziridine ring expansion of 2-[(aziridin-1-yl-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters

    Directory of Open Access Journals (Sweden)

    U. K. Syam Kumar

    2011-06-01

    Full Text Available A novel synthetic methodology has been developed for the synthesis of diethyl 5-alkyl/aryl/heteroaryl substituted 3,4-dihydro-2H-pyrrole-4,4-dicarboxylates (also called 2-substituted pyrroline-4,5-dihydro-3,3-dicarboxylic acid diethyl esters by iodide ion induced ring expansion of 2-[(aziridin-1-yl-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters in very good to excellent yields under mild reaction conditions. The electronic and steric impact of the substituents on the kinetics of ring expansion of N-vinyl aziridines to pyrrolines has been studied. Various diversely substituted novel pyrroline derivatives have been synthesized by this methodology and the products can be used as key intermediates in the synthesis of substituted pyrrolines, pyrroles and pyrrolidines.

  7. Schiff bases of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane and its silatranes: Synthesis and characterization

    Indian Academy of Sciences (India)

    Gurjaspreet Singh; Amandeep Saroa; Sadhika Khullar; Sanjay K Mandal

    2015-04-01

    This paper aims at the introduction of azomethine group by the condensation reaction of N-(2-aminoethyl)-3-aminopropyltrimethoxysilane with different compounds containing carbonyl group such as 2’-hydroxyacetophenone, salicylaldehyde, pyrrole-2-carboxaldehyde, acetylacetone and ethyl acetoacetate. Further, transesterification reaction of these Schiff base modified silanes with triethanolamine as a tripodal ligand leads to the synthesis of corresponding silatranes 1–5 bearing Schiff base functionalized long chain in the axial position. All the synthesized compounds are characterized by spectroscopic methods, elemental analysis and mass spectrometry. The authentication of Schiff base modified silatranes is scrutinized by single X-ray crystal structure of silatrane 1. The thermal stability of the five silatranes is studied by thermo-gravimetric analysis (TGA).

  8. Synthesis and characterization of a novel meso-porphyrin and its metallo derivatives

    Directory of Open Access Journals (Sweden)

    Paulo Cesar Bega

    2014-02-01

    Full Text Available There has been a growing interest in the properties of substituted meso-tetraarylporphyrins and metallo porphyrins as catalysts for oxidation of hydrocarbons, oxygen detection, among others. This work describes the synthesis of a new porphyrin, 5,10,15,20-tetrakis(4-butoxy-3-methoxyphenylporphyrin, and its metallo complexes. Herein it was used a readily available reactant, vanillin, as starting material which was submitted to alkylation with n-bromobutane affording the synthetic precursor. The desired porphyrin was obtained by reacting the O-alkylated aldehyde with pyrrole in the presence of propionic acid (Alder-Longo method. The purified porphyrin was then subjected to the metallation process using iron (II and manganese (II salts. The synthesized compounds were characterized by IR, UV-Vis, NMR and EPR spectroscopy.

  9. Electron-deficient N-alkyloyl derivatives of thieno[3,4-c]pyrrole-4,6-dione yield efficient polymer solar cells with open-circuit voltages > 1 v

    KAUST Repository

    Warnan, Julien

    2014-05-13

    Poly(benzo[1,2-b:4,5-b′]dithiophene-thieno[3,4-c]pyrrole-4,6-dione) (PBDTTPD) polymer donors yield some of the highest open-circuit voltages (V OC, ca. 0.9 V) and fill factors (FF, ca. 70%) in conventional bulk-heterojunction (BHJ) solar cells with PCBM acceptors. Recent work has shown that the incorporation of ring substituents into the side chains of the BDT motifs in PBDTTPD can induce subtle variations in material properties, resulting in an increase of the BHJ device VOC to ∼1 V. In this contribution, we report on the synthesis of N-alkyloyl-substituted TPD motifs (TPD(CO)) and show that the electron-deficient motifs can further lower both the polymer LUMO and HOMO levels, yielding device VOC > 1 V (up to ca. 1.1 V) in BHJ solar cells with PCBM. Despite the high VOC achieved (i.e., low polymer HOMO), BHJ devices cast from TPD(CO)-based polymer donors can reach power conversion efficiencies (PCEs) of up to 6.7%, making these promising systems for use in the high-band-gap cell of tandem solar cells. © 2014 American Chemical Society.

  10. Ultrafast photoexcited dynamics probe of blends of conjugated polymerpoly{bi(dodecyl)thiophene-thieno[3,4-c]pyrrole-4,6-dione} and fullerenes for photovoltaic applications with broadband sub-10-fs visible pulse

    Science.gov (United States)

    Kao, Chih-Hsien; Yabushita, Atsushi; Su, Yu-Wei; Wei, Kung-Hwa; Lee, Yu-Hsien; Kobayashi, Takayoshi

    2016-03-01

    Conjugated polymers have been widely studied as active materials for organic solar cells, which are a promising replacement for silicon solar cells. A novel electron donor polymer of poly{bi(dodecyl)thiophene-thieno[3,4-c]pyrrole-4,6-dione} (PBTTPD) blended with an electron acceptor, [6,6]-phenyl C71 butyric acid methyl ester (PC71BM), gave a device power conversion efficiency as high as 7.3%. In the present work, we performed time-resolved absorption change spectroscopy at various mixture ratios of PC71BM in the PBTTPD/PC71BM blend. Among the obtained time constants, the shortest (60 fs) and the longest (500 fs and 15 ps) were assigned to the production and relaxation of charge-transfer (CT) states, respectively. The PC71BM blended with PBTTPD was found to suppress interchain carrier transport and increase intrachain carrier transport. The prolonged lifetime of the CT state in the equally blended PBTTPD/PC71BM film increases the probability of charge separation and thus increases the power conversion efficiency of the device.

  11. Linear side chains in benzo[1,2-b:4,5-b′]dithiophene-thieno[3,4-c] pyrrole-4,6-dione polymers direct self-assembly and solar cell performance

    KAUST Repository

    Cabanetos, Clement

    2013-03-27

    While varying the size and branching of solubilizing side chains in π-conjugated polymers impacts their self-assembling properties in thin-film devices, these structural changes remain difficult to anticipate. This report emphasizes the determining role that linear side-chain substituents play in poly(benzo[1,2-b:4,5-b′]dithiophene-thieno[3,4-c]pyrrole-4,6-dione) (PBDTTPD) polymers for bulk heterojunction (BHJ) solar cell applications. We show that replacing branched side chains by linear ones in the BDT motifs induces a critical change in polymer self-assembly and backbone orientation in thin films that correlates with a dramatic drop in solar cell efficiency. In contrast, we show that for polymers with branched alkyl-substituted BDT motifs, controlling the number of aliphatic carbons in the linear N-alkyl-substituted TPD motifs is a major contributor to improved material performance. With this approach, PBDTTPD polymers were found to reach power conversion efficiencies of 8.5% and open-circuit voltages of 0.97 V in BHJ devices with PC71BM, making PBDTTPD one of the best polymer donors for use in the high-band-gap cell of tandem solar cells. © 2013 American Chemical Society.

  12. Ethyl-2-amino-pyrrole-3-carboxylates are novel potent anticancer agents that affect tubulin polymerization, induce G2/M cell-cycle arrest, and effectively inhibit soft tissue cancer cell growth in vitro.

    Science.gov (United States)

    Boichuk, Sergei; Galembikova, Aigul; Zykova, Svetlana; Ramazanov, Bulat; Khusnutdinov, Ramil; Dunaev, Pavel; Khaibullina, Svetlana; Lombardi, Vincent

    2016-08-01

    Microtubules are known to be one of the most attractive and validated targets in cancer therapy. However, the clinical use of drugs that affect the dynamic state of microtubules has been hindered by chemoresistance and toxicity issues. Accordingly, the development of novel agents that target microtubules is needed. Here, we report the identification of novel compounds with pirrole and carboxylate structures: ethyl-2-amino-pyrrole-3-carboxylates (EAPCs) that provide potent cytotoxic activities against multiple soft tissue cancer cell lines in vitro. Using the MTS cell proliferation assay, we assessed the activity of EAPCs on various cancer cell lines including leiomyosarcoma SK-LMS-1, rhabdomyosarcoma RD, gastrointestinal stromal tumor GIST-T1, A-673 Ewing's sarcoma, and U-2 OS osteosarcoma. We found that in the majority of cases, two EAPC compounds (EAPC-20 and EAPC-24) considerably inhibited cancer cell proliferation in vitro. The growth-inhibitory effects of EAPC-20 and EAPC-24 were time and dose dependent. The molecular mechanisms of action of these compounds were because of the inhibition of tubulin polymerization and induction of a robust G2/M cell-cycle arrest, leading to considerable accumulation of tumor cells in the M-phase. Finally, EAPCs induced tumor cell death by apoptotic pathways. The above-mentioned effects were also observed in most soft tissue tumor cell lines and the gastrointestinal stromal tumor cell line investigated. Taken together, our data identify potent antitumor activity of EAPCs in vitro, thus providing a novel scaffold with which to develop potent chemotherapeutic agents for cancer therapy. PMID:27129079

  13. The formation of [M-H]+ ions in N-alkyl-substituted thieno[3,4-c]-pyrrole-4,6-dione derivatives during atmospheric pressure photoionization mass spectrometry

    KAUST Repository

    Sioud, Salim

    2014-10-09

    RESULTS [M-H]+ ions were observed under APPI conditions. The type of dopant and the length of the alkyl chain affected the formation of these ions. MS/MS fragmentation of [M-H]+ and [M + H]+ ions exhibited completely different patterns. Theoretical calculations revealed that the loss of hydrogen molecules from the [M + H]+ ions is the most favourable condition under which to form [M-H]+ ions.CONCLUSIONS [M-H]+ ions were detected in all the TPD derivatives studied here under the special experimental conditions during APPI, using a halogenated benzene dopant, and TPD containing substituted N-alkyl side chains with a minimum of four carbon atoms. Density functional theory calculations showed that for [M-H]+ ions to be formed under these conditions, the loss of hydrogen molecules from the [M + H]+ ions is proposed to be necessary.RATIONALE The formation of ions during atmospheric pressure photoionization (APPI) mass spectrometry in the positive mode usually provides radical cations and/or protonated species. Intriguingly, during the analysis of some N-alkyl-substituted thieno[3,4-c]pyrrole-4,6-dione (TPD) derivatives synthesized in our laboratory, unusual [M-H]+ ion peaks were observed. In this work we investigate the formation of [M-H]+ ions observed under APPI conditions.METHODS Multiple experimental parameters, including the type of ionization source, the composition of the solvent, the type of dopant, the infusion flow rate, and the length of the alkyl side chain were investigated to determine their effects on the formation of [M-H]+ ions. In addition, a comparison study of the gas-phase tandem mass spectrometric (MS/MS) fragmentation of [M + H]+ vs [M-H]+ ions and computational approaches were used.

  14. Sensitive and selective electrochemical determination of quinoxaline-2-carboxylic acid based on bilayer of novel poly(pyrrole) functional composite using one-step electro-polymerization and molecularly imprinted poly(o-phenylenediamine).

    Science.gov (United States)

    Yang, Yukun; Fang, Guozhen; Wang, Xiaomin; Pan, Mingfei; Qian, Hailong; Liu, Huilin; Wang, Shuo

    2014-01-01

    A facile and efficient molecularly imprinted polymer (MIP) recognition element of electrochemical sensor was fabricated by directly electro-polymerizing monomer o-phenylenediamine (oPD) in the presence of template quinoxaline-2-carboxylic acid (QCA), based on one-step controllable electrochemical modification of poly(pyrrole)-graphene oxide-binuclear phthalocyanine cobalt (II) sulphonate (PPY-GO-BiCoPc) functional composite on glassy carbon electrode (GCE). The MIP film coated on PPY-GO-BiCoPc functional composite decorated GCE (MIP/PPY-GO-BiCoPc/GCE) was presented for the first time. The synergistic effect and electro-catalytic activity toward QCA redox of PPY-GO-BiCoPc functional composite were discussed using various contrast tests. Also, the effect of experimental variables on the current response such as, electro-polymerization cycles, template/monomer ratio, elution condition for template removal, pH of the supporting electrolyte and accumulation time, were investigated in detail. Under the optimized conditions, the proposed MIP sensor possessed a fast rebinding dynamics and an excellent recognition capacity to QCA, while the anodic current response of square wave voltammetry (SWV) was well-proportional to the concentration of QCA in the range of 1.0×10(-8)-1.0×10(-4) and 1.0×10(-4)-5.0×10(-4) mol L(-1) with a low detection limit of 2.1 nmol L(-1). The established sensor was applied successfully to determine QCA in commercial pork and chicken muscle samples with acceptable recoveries (91.6-98.2%) and satisfactory precision (1.9-3.5% of SD), demonstrating a promising feature for applying the MIP sensor to the measurement of QCA in real samples.

  15. Detailed characterization of a Comparative Reactivity Method (CRM) instrument for ambient OH reactivity measurements: experiments vs. modeling

    Science.gov (United States)

    Michoud, Vincent; Locoge, Nadine; Dusanter, Sébastien

    2015-04-01

    The Hydroxyl radical (OH) is the main daytime oxidant in the troposphere, leading to the oxidation of Volatile Organic Compounds (VOCs) and the formation of harmful pollutants such as ozone (O3) and Secondary Organic Aerosols (SOA). While OH plays a key role in tropospheric chemistry, recent studies have highlighted that there are still uncertainties associated with the OH budget, i.e the identification of sources and sinks and the quantification of production and loss rates of this radical. It has been demonstrated that ambient measurements of the total OH loss rate (also called total OH reactivity) can be used to identify and reduce these uncertainties. In this context, the Comparative Reactivity Method (CRM), developed by Sinha et al. (ACP, 2008), is a promising technique to measure total OH reactivity in ambient air and has already been used during several field campaigns. This technique relies on monitoring competitive reactions of OH with ambient trace gases and a reference compound (pyrrole) in a sampling reactor to derive ambient OH reactivity. However, this technique requires a complex data processing chain that has yet to be carefully investigated in the laboratory. In this study, we present a detailed characterization of a CRM instrument developed at Mines Douai, France. Experiments have been performed to investigate the dependence of the CRM response on humidity, ambient NOx levels, and the pyrrole-to-OH ratio inside the sampling reactor. Box modelling of the chemistry occurring in the reactor has also been performed to assess our theoretical understanding of the CRM measurement. This work shows that the CRM response is sensitive to both humidity and NOx, which can be accounted for during data processing using parameterizations depending on the pyrrole-to-OH ratio. The agreement observed between laboratory studies and model results suggests a good understanding of the chemistry occurring in the sampling reactor and gives confidence in the CRM

  16. Sensitive and selective electrochemical determination of quinoxaline-2-carboxylic acid based on bilayer of novel poly(pyrrole) functional composite using one-step electro-polymerization and molecularly imprinted poly(o-phenylenediamine)

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Yukun; Fang, Guozhen; Wang, Xiaomin; Pan, Mingfei; Qian, Hailong; Liu, Huilin; Wang, Shuo, E-mail: s.wang@tust.edu.cn

    2014-01-02

    Graphical abstract: -- Highlights: •PPY-GO-BiCoPc composite was formed using a simple electrochemical method for the first time. •A novel PoPD-MIP sensor based on PPY-GO-BiCoPc composite had been fabricated. •The PPY-GO-BiCoPc functional composite was introduced to improve performance of the sensor. •Highly sensitive, selective and stable sensor had been achieved. •The established MIP sensor could be promising in food safety analysis. -- Abstract: A facile and efficient molecularly imprinted polymer (MIP) recognition element of electrochemical sensor was fabricated by directly electro-polymerizing monomer o-phenylenediamine (oPD) in the presence of template quinoxaline-2-carboxylic acid (QCA), based on one-step controllable electrochemical modification of poly(pyrrole)-graphene oxide-binuclear phthalocyanine cobalt (II) sulphonate (PPY-GO-BiCoPc) functional composite on glassy carbon electrode (GCE). The MIP film coated on PPY-GO-BiCoPc functional composite decorated GCE (MIP/PPY-GO-BiCoPc/GCE) was presented for the first time. The synergistic effect and electro-catalytic activity toward QCA redox of PPY-GO-BiCoPc functional composite were discussed using various contrast tests. Also, the effect of experimental variables on the current response such as, electro-polymerization cycles, template/monomer ratio, elution condition for template removal, pH of the supporting electrolyte and accumulation time, were investigated in detail. Under the optimized conditions, the proposed MIP sensor possessed a fast rebinding dynamics and an excellent recognition capacity to QCA, while the anodic current response of square wave voltammetry (SWV) was well-proportional to the concentration of QCA in the range of 1.0 × 10{sup −8}–1.0 × 10{sup −4} and 1.0 × 10{sup −4}–5.0 × 10{sup −4} mol L{sup −1} with a low detection limit of 2.1 nmol L{sup −1}. The established sensor was applied successfully to determine QCA in commercial pork and chicken muscle

  17. 4-Hydroxy-7-oxo-5-heptenoic Acid (HOHA) Lactone is a Biologically Active Precursor for the Generation of 2-(ω-Carboxyethyl)pyrrole (CEP) Derivatives of Proteins and Ethanolamine Phospholipids.

    Science.gov (United States)

    Wang, Hua; Linetsky, Mikhail; Guo, Junhong; Choi, Jaewoo; Hong, Li; Chamberlain, Amanda S; Howell, Scott J; Howes, Andrew M; Salomon, Robert G

    2015-05-18

    2-(ω-Carboxyethyl)pyrrole (CEP) derivatives of proteins were previously shown to have significant pathological and physiological relevance to age-related macular degeneration, cancer and wound healing. Previously, we showed that CEPs are generated in the reaction of ε-amino groups of protein lysyl residues with 1-palmityl-2-(4-hydroxy-7-oxo-5-heptenoyl)-sn-glycero-3-phosphatidylcholine (HOHA-PC), a lipid oxidation product uniquely generated by oxidative truncation of docosahexanenate-containing phosphatidylcholine. More recently, we found that HOHA-PC rapidly releases HOHA-lactone and 2-lyso-PC (t1/2 = 30 min at 37 °C) by nonenzymatic transesterification/deacylation. Now we report that HOHA-lactone reacts with Ac-Gly-Lys-OMe or human serum albumin to form CEP derivatives in vitro. Incubation of human red blood cell ghosts with HOHA-lactone generates CEP derivatives of membrane proteins and ethanolamine phospholipids. Quantitative analysis of the products generated in the reaction HOHA-PC with Ac-Gly-Lys-OMe showed that HOHA-PC mainly forms CEP-dipeptide that is not esterified to 2-lysophosphatidycholine. Thus, the HOHA-lactone pathway predominates over the direct reaction of HOHA-PC to produce the CEP-PC-dipeptide derivative. Myleoperoxidase/H2O2/NO2(-) promoted in vitro oxidation of either 1-palmityl-2-docosahexaneoyl-sn-glycero-3-phosphatidylcholine (DHA-PC) or docosahexaenoic acid (DHA) generates HOHA-lactone in yields of 0.45% and 0.78%, respectively. Lipid oxidation in human red blood cell ghosts also releases HOHA-lactone. Oxidative injury of ARPE-19 human retinal pigmented epithelial cells by exposure to H2O2 generated CEP derivatives. Treatment of ARPE-19 cells with HOHA-lactone generated CEP-modified proteins. Low (submicromolar), but not high, concentrations of HOHA-lactone promote increased vascular endothelial growth factor (VEGF) secretion by ARPE-19 cells. Therefore, HOHA-lactone not only serves as an intermediate for the generation of CEPs but

  18. Synthesis and preliminary characterization of radioiodinated benzofuran-3-yl-(indol-3-yl)maleimide derivatives as potential SPECT imaging probes for the detection of glycogen synthase kinase-3β (GSK-3β) in the brain.

    Science.gov (United States)

    Ono, Masahiro; Kitada, Ayane; Watanabe, Hiroyuki; Miyazaki, Anna; Kimura, Hiroyuki; Saji, Hideo

    2016-06-30

    We report on the synthesis and preliminary characterization of two radioiodinated benzofuran-3-yl-(indol-3-yl)maleimides, 3-(benzofuran-3-yl)-4-(5-[(125) I]iodo-1-methyl-1H-indol-3-yl)-1H-pyrrole-2,5-dione ([(125) I]5), and 3-(5-[(125) I]iodo-1-methyl-1H-indol-3-yl)-4-(6-methoxybenzofuran-3-yl)-1H-pyrrole-2,5-dione ([(125) I]6), as the first potential SPECT imaging probes targeting glycogen synthase kinase-3β (GSK-3β). In this study, we used (125) I as a surrogate of (123) I because of its ease of use. The radioiodinated ligands were prepared from the corresponding tributyltin precursors through an iododestannylation reaction using hydrogen peroxide as an oxidant with a radiochemical yield of 10-30%. In vitro binding experiments suggested that both compounds show high affinity for GSK-3β at a level similar to a known GSK-3β inhibitor. Biodistribution studies with normal mice revealed that the radioiodinated compounds display sufficient uptake into (1.8%ID/g at 10 min postinjection) and clearance from the brain (1.0%ID/g at 60 min postinjection). These preliminary results suggest that the further optimization of radioiodinated benzofuran-3-yl-(indol-3-yl)maleimide derivatives may facilitate the development of clinically useful SPECT imaging probes for the in vivo detection of GSK-3β. PMID:27126914

  19. Synthesis, spectroscopic characterizations, crystal structures and DFT studies of nalidixic acid carbonyl hydrazones derivatives

    Science.gov (United States)

    Bergamini, F. R. G.; Ribeiro, M. A.; Lancellotti, M.; Machado, D.; Miranda, P. C. M. L.; Cuin, A.; Formiga, A. L. B.; Corbi, P. P.

    2016-09-01

    This article describes the synthesis and characterization of the 1-ethyl-7-methyl-4-oxo-1,4-dihydro-1,8-naphthyridine-3-carbohydrazide (hzd) and six carbonyl hydrazones derivatives of the nalidixic with 1H-pyrrol-2-ylmethylidene (hpyrr), 1H-imidazol-2-ylmethylidene (h2imi), pyridin-2-ylmethylidene (h2py), pyridin-3-ylmethylidene (h3py), pyridin-4-ylmethylidene(h4py) and (2-hydroxyphenyl)methylidene (hsali). The carbonyl hydrazones were characterized by elemental and ESI-QTOF-MS analyses, IR and detailed NMR spectroscopic measurements. The 2D NMR experiments allowed the unambiguous assignment of the hydrogen, carbon and nitrogen atoms, which have not been reported for nalidixic acid carbonyl hydrazone derivatives so far. Crystal structures of hzd and the new carbonyl hydrazones h2imi, hpyrr and h3py were determined by X-ray diffraction studies. Although the synthesis of hzd was reported decades ago, the hzd crystal structure have not been reported yet. Geometric optimizations of all the characterized structures were performed with the aid of DFT studies. Despite the fact that the hydrazones with 2-pyridine carboxylic acid (h2py) and salicyl aldehyde (hsali) were already reported by literature, a detailed spectroscopic study followed by DFT studies are also reported for such compounds in this manuscript. Antimicrobial studies of the compounds are also presented.

  20. Bioactivation of 4-ipomeanol by CYP4B1: adduct characterization and evidence for an enedial intermediate.

    Science.gov (United States)

    Baer, Brian R; Rettie, Allan E; Henne, Kirk R

    2005-05-01

    4-Ipomeanol (IPO) is a pneumotoxin that is bioactivated to a reactive intermediate that binds to DNA and other cellular macromolecules. Despite over 30 years of research in this area, detailed structural information on the nature of the IPO reactive intermediate is still lacking. In the present study, we reacted IPO with rabbit CYP4B1 in the presence of exogenous nucleophiles and analyzed the products by liquid chromatography/electrospray ionization-mass spectrometry. Coincubation of IPO and rabbit CYP4B1 with glutathione gave rise to multiple products due likely to the presence of both sulfur and nitrogen nucleophiles in the same trapping molecule. Reaction mixtures containing equimolar N-acetyl cysteine (NAC) and N-acetyl lysine (NAL) provided a major NADPH- and CYP4B1-dependent product. A combination of high-resolution mass spectrometry and two-dimensional NMR analysis following large-scale isolation of the biologically derived material provided evidence for an N-substituted cysteinyl pyrrole derivative of IPO, analogous to that characterized previously in model chemical studies conducted with cis-2-butene-1,4-dial. Purified native rabbit lung CYP4B1 and purified recombinant rabbit CYP4B1 produced the trapped NAC/NAL-IPO pyrrole adduct at rates of 600-700 nmol/nmol P450/30 min. A panel of 14 commercially available recombinant human CYPs was also studied, and substantial rates of IPO bioactivation (>100 nmol/nmol/30 min) were observed with CYP1A2, CYP2C19, CYP2D6, and CYP3A4. These studies provide evidence for the formation of an enedial reactive intermediate during CYP-mediated IPO bioactivation, identify multiple human liver P450s capable of IPO bioactivation, and demonstrate that the same reactive intermediate is formed by both rabbit CYP4B1 and human P450s. PMID:15892579

  1. Detailed characterizations of a Comparative Reactivity Method (CRM) instrument: experiments vs. modelling

    Science.gov (United States)

    Michoud, V.; Hansen, R. F.; Locoge, N.; Stevens, P. S.; Dusanter, S.

    2015-04-01

    The Hydroxyl radical (OH) is an important oxidant in the daytime troposphere that controls the lifetime of most trace gases, whose oxidation leads to the formation of harmful secondary pollutants such as ozone (O3) and Secondary Organic Aerosols (SOA). In spite of the importance of OH, uncertainties remain concerning its atmospheric budget and integrated measurements of the total sink of OH can help reducing these uncertainties. In this context, several methods have been developed to measure the first-order loss rate of ambient OH, called total OH reactivity. Among these techniques, the Comparative Reactivity Method (CRM) is promising and has already been widely used in the field and in atmospheric simulation chambers. This technique relies on monitoring competitive OH reactions between a reference molecule (pyrrole) and compounds present in ambient air inside a sampling reactor. However, artefacts and interferences exist for this method and a thorough characterization of the CRM technique is needed. In this study, we present a detailed characterization of a CRM instrument, assessing the corrections that need to be applied on ambient measurements. The main corrections are, in the order of their integration in the data processing: (1) a correction for a change in relative humidity between zero air and ambient air, (2) a correction for the formation of spurious OH when artificially produced HO2 react with NO in the sampling reactor, and (3) a correction for a deviation from pseudo first-order kinetics. The dependences of these artefacts to various measurable parameters, such as the pyrrole-to-OH ratio or the bimolecular reaction rate constants of ambient trace gases with OH are also studied. From these dependences, parameterizations are proposed to correct the OH reactivity measurements from the abovementioned artefacts. A comparison of experimental and simulation results is then discussed. The simulations were performed using a 0-D box model including either (1) a

  2. Synthesis of Pyrrole-Imidazole Polyamide

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    One simple and versatile method is established for the synthesis of DNA recognition molecules-polyamides containing alternating N-methylpyrrole and N-methylimidazole without necessitating NH2- group protection.

  3. Pyrrole-Based Conductive Polymers For Capacitors

    Science.gov (United States)

    Nagasubramanian, Ganesan; Di Stefano, Salvador

    1994-01-01

    Polypyrrole films containing various dopant anions exhibit superior capacitance characteristics. Used with nonaqueous electrolytes. Candidate for use in advanced electrochemical double-layer capacitors capable of storing electrical energy at high densities. Capacitors made of these films used in automobiles and pulsed power supplies.

  4. Crystal structure of ethyl 2-(2-{1-[N-(4-bromo­phen­yl)-2-oxo-2-phenyl­acetamido]-2-tert-butyl­amino-2-oxo­ethyl}-1H-pyrrol-1-yl)acetate

    OpenAIRE

    Moriguchi, Tetsuji; Jalli, Venkataprasad; Krishnamurthy, Suvratha; Tsuge, Akihiko; Yoza, Kenji

    2015-01-01

    In the title compound, C28H30BrN3O5, there is an intra­molecular N—H⋯O hydrogen bond and an intra­molecular C—H⋯O hydrogen bond, both forming S(9) ring motifs. The planes of the 4-bromo­phenyl ring and the phenyl ring are inclined to that of the pyrrole ring by 48.05 (12) and 77.45 (14)°, respectively, and to one another by 56.25 (12)°. In the crystal, mol­ecules are linked via C—H⋯O hydrogen bonds and C—H⋯π inter­actions, forming slabs parallel to (10-1).

  5. Metal based new triazoles: Their synthesis, characterization and antibacterial/antifungal activities

    Science.gov (United States)

    Sumrra, Sajjad H.; Chohan, Zahid H.

    2012-12-01

    A series of new triazoles and their oxovanadium(IV) complexes have been synthesized, characterized and evaluated for antibacterial/antifungal properties. The new Schiff bases ligands (L1)-(L5) were prepared by the condensation reaction of 3,5-diamino-1,2,4-triazole with 2-hydroxy-1-naphthaldehyde, pyrrole-2-carboxaldehyde, pyridine-2-carboxaldehyde, 2-acetyl pyridine and 2-methoxy benzaldehyde. The structures of the ligands have been established on the basis of their physical, spectral (IR, 1H and 13C NMR and mass spectrometry) and elemental analytical data. The prepared ligands were used to synthesize their oxovanadium(IV) complexes (1)-(5) which were also characterized by their physical, spectral and analytical data and proposed to have a square pyramidal geometry. The ligands and their complexes were screened for in vitro antibacterial activity against six bacterial species such as, Escherichia coli, Shigella flexneri, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus, and Bacillus subtilis and for in vitro antifungal activity against six fungal strains, Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani, and Candida glabrata. Cytotoxic nature of the compounds was also reported using brine shrimp bioassay method against Artemia salina.

  6. 2,4-二甲基吡咯-3,5-二羧酸二乙酯的合成--推荐一个大学有机化学实验%Synthesis of Diethyl 2,4-dimethyl-pyrrole-3,5-dicarboxylate:Recommending a University Organic Chemistry Experiment

    Institute of Scientific and Technical Information of China (English)

    汪剑波; 宗乾收; 沈锦锦; 毕成; 吴晨俊

    2016-01-01

    Using Knorr pyrrole synthesis, diethyl 2,4-dimethyl-pyrrole-3,5-dicarboxylate was synthesized via one-pot method with ethyl acetoacetate and sodium nitrite as starting materials in the presence of acetic acid and zinc powder. The experiment involves the experimental operation and analyses including temperature control, reflux, recrystal ization, melting point, IR and NMR spectroscopies. The advantages of the experiment are simple raw materials and high product yield. The experiment is helpful for cultivating and improving the synthesis ability of students, as wel as in-depth understanding of heterocyclic synthesis and spectral analysis.%采用Knorr吡咯合成法,以乙酰乙酸乙酯和亚硝酸钠为原料,在醋酸和锌粉作用下采用“一锅法”得到2,4-二甲基吡咯-3,5-二羧酸二乙酯。本实验涉及到控温、回流、重结晶、熔点测定、红外光谱及核磁共振等实验操作和分析检测方法。该实验原料简单易得、产物收率高,结合波谱解析方法,可以培养和提高学生合成实验的能力,加强学生对杂环合成和波谱解析的理解与分析。

  7. In-vitro investigations of the speed of pyrrole formation of 2,5-hexanedione and 2,5-heptanedione with N{alpha}-acetyl-L-lysine as a precondition for a comparative assessment of the neurotoxic potentials of the two {gamma}-diketones; In-vitro-Untersuchungen zur Pyrrolbildungsgeschwindigkeit von 2,5-Hexandion und 2,5-Heptandion mit N{alpha}-Acetyl-L-lysin als Voraussetzung fuer eine vergleichende Abschaetzung der neurotoxischen Potentiale beider {gamma}-Diketone

    Energy Technology Data Exchange (ETDEWEB)

    Richter, M.F.

    1997-09-01

    N-hexane and n-heptane are important solvents. Chronic exposure to n-hexane causes polyneuropathies, which are attributed to the metabolite 2,5-hexanedione, a {gamma} diketone. As a basis for a comparative assessment of the neurotoxic potentials of 2,5-hexanedione and 2,5-heptanedione, an in-vitro test was developed and used to investigate the speed of pyrrole formation of the two {gamma} diketones in reacting with the {epsilon} amino group of N{alpha}-acetyl L-lysine. The speed of the formation of pyrrole was always directly proportional to the respective reactant concentration. It consequently is subject to a second-order kinetics. As a further result, the pyrrole formation speed of 2,5-heptanedione was found to be only half that of 2,5-hexanedione. The results lead to the conclusion that 2,5-heptanedione poses a smaller risk of developing peripheral neuropathy than 2,5-hexanedione. (orig./MG) [Deutsch] n-Hexan und n-Heptan sind wichtige Loesungsmittel. Chronische Exposition gegenueber n-Hexan ruft Polyneuropathien hervor, die auf den Metaboliten 2,5-Hexandion, ein {gamma}-Diketon, zurueckgefuehrt werden. Als Grundlage fuer eine vergleichende Abschaetzung der neurotoxischen Potentiale von 2,5-Hexandion und 2,5-Heptandion wurde in der vorliegenden Arbeit ein In-vitro-Test entwickelt, mit dem die Pyrrolbildungsgeschwindigkeiten der beiden {gamma}-Diketone mit der {epsilon}-Aminogruppe von N{alpha}-Acetyl-L-Iysin untersucht wurden. Die Pyrrolbildungsgeschwindigkeit war stets direkt proportional zur jeweiligen Reaktantenkonzentration. Somit unterliegt sie einer Kinetik 2. Ordnung. Weiterhin wurde gezeigt, dass die Pyrrolbildungsgeschwindigkeit fuer 2,5-Heptandion nur etwa halb so gross ist wie fuer 2,5-Hexandion. Aus den Ergebnissen wird gefolgert, dass das von 2,5-Heptandion ausgehende Risiko an peripheren Neuropathien zu erkranken geringer ist, als das von 2,5-Hexandion ausgehende. (orig./MG)

  8. Preparation and characterization of electrical conductive PVA based materials for peripheral nerve tube-guides.

    Science.gov (United States)

    Gonçalves, C; Ribeiro, J; Pereira, T; Luís, A L; Mauricio, A C; Santos, J D; Lopes, M A

    2016-08-01

    Peripheral nerve regeneration is a serious clinical problem. Presently, there are several nerve tube-guides available in the market, however with some limitations. The goal of this work was the development of a biomaterial with high electrical conductivity to produce tube-guides for nerve regeneration after neurotmesis injuries whenrver an end-to-end suture without tension is not possible. A matrix of poly(vinyl alcohol) (PVA) was used loaded with the following electrical conductive materials: COOH-functionalized multiwall carbon nanotubes (MWCNTs), poly(pyrrole) (PPy), magnesium chloride (MgCl2 ), and silver nitrate (AgNO3 ). The tube-guide production was carried out by a freezing/thawing process (physical crosslinking) with a final annealing treatment. After producing the tube-guide for nerve regeneration, the physicochemical characterization was performed. The most interesting results were achieved by loading PVA with 0.05% of PPy or COOH- functionalized CNTs. These tubes combined the electrical conductivity of carbon nanotubes (CNTs) and PPy with the biocompatibility of PVA matrix, with potential clinical application for nerve regeneration. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1981-1987, 2016. PMID:27027727

  9. Synthesis, characterization and a.c. conductivity of polypyrrole/Y2O3 composites

    Indian Academy of Sciences (India)

    T K Vishnuvardhan; V R Kulkarni; C Basavaraja; S C Raghavendra

    2006-02-01

    Conducting polymer composites of polypyrrole/yttrium oxide (PPy/Y2O3) were synthesized by in situ polymerization of pyrrole with Y2O3 using FeCl3 as an oxidant. The Y2O3 is varied in five different weight percentages of PPy in PPy/Y2O3 composites. The synthesized polymer composites are characterized by infrared and X-ray diffraction techniques. The surface morphology of the composite is studied by scanning electron microscopy. The glass transition temperature of the polymer and its composite is discussed by DSC. Electrical conductivity of the compressed pellets depends on the concentration of Y2O3 in PPy. The frequency dependent a.c. conductivity reveals that the Y2O3 concentration in PPy is responsible for the variation of conductivity of the composites. Frequency dependent dielectric constant at room temperature for different composites are due to interfacial space charge (Maxwell Wagner) polarization leading to the large value of dielectric constant. Frequency dependent dielectric loss, as well as variation of dielectric loss as a function of mass percentage of Y2O3 is also presented and discussed.

  10. Cellulose aerogels functionalized with polypyrrole and silver nanoparticles: In-situ synthesis, characterization and antibacterial activity.

    Science.gov (United States)

    Wan, Caichao; Li, Jian

    2016-08-01

    Green porous and lightweight cellulose aerogels have been considered as promising candidates to substitute some petrochemical host materials to support various nanomaterials. In this work, waste wheat straw was collected as feedstock to fabricate cellulose hydrogels, and a green inexpensive NaOH/polyethylene glycol solution was used as cellulose solvent. Prior to freeze-drying treatment, the cellulose hydrogels were integrated with polypyrrole and silver nanoparticles by easily-operated in-situ oxidative polymerization of pyrrole using silver ions as oxidizing agent. The tri-component hybrid aerogels were characterized by scanning electron microscope, transmission electron microscope, energy dispersive X-ray spectroscopy, selected area electron diffraction, X-ray photoelectron spectroscopy, and X-ray diffraction. Moreover, the antibacterial activity of the hybrid aerogels against Escherichia coli (Gram-negative), Staphylococcus aureus (Gram-positive) and Listeria monocytogenes (intracellular bacteria) was qualitatively and quantitatively investigated by parallel streak method and determination of minimal inhibitory concentration, respectively. This work provides an example of combining cellulose aerogels with nanomaterials, and helps to develop novel forms of cellulose-based functional materials. PMID:27112885

  11. The application of zero-current potentiometry in chemical synthesis and characterization of polypyrrole using electrochemical sensors

    Energy Technology Data Exchange (ETDEWEB)

    Budimir, M.V. (Faculty of Agriculture, Univ. of Osijek (Yugoslavia)); Sak-Bosnar, M. (Pedagogical Faculty, Univ. of Osijek (Yugoslavia)); Kovac, S. (Faculty of Food Tech., Univ. of Osijek (Yugoslavia)); Duic, L. (Faculty of Tech., Inst. of Electrochemistry, Univ. of Zagreb (Yugoslavia))

    1991-01-01

    The chemical polymerization of pyrrole to highly conducting polypyrrole in aqueous and acetonitrile solutions using various oxidizing agents was studied. The course of synthesis was followed using zero-current potentiometry with a platinum reference electrode as redox sensor. The obtained results can be used for a better understanding of pyrrole polymerization kinetics. In addition, the halogenide-ion content as counter ion can be determined potentiometrically after chemical degradation of polypyrrole using a chloride-selective electrode as sensor. (orig.).

  12. Column solid phase extraction and flame atomic absorption spectrometric determination of manganese(II) and iron(III) ions in water, food and biological samples using 3-(1-methyl-1H-pyrrol-2-yl)-1H-pyrazole-5-carboxylic acid on synthesized graphene oxide.

    Science.gov (United States)

    Pourjavid, Mohammad Reza; Sehat, Ali Akbari; Arabieh, Masoud; Yousefi, Seyed Reza; Hosseini, Majid Haji; Rezaee, Mohammad

    2014-02-01

    A modified, selective, highly sensitive and accurate procedure for the determination of trace amounts of manganese and iron ions is established in the presented work. 3-(1-Methyl-1H-pyrrol-2-yl)-1H-pyrazole-5-carboxylic acid (MPPC) and graphene oxide (GO) were used in a glass column as chelating reagent and as adsorbent respectively prior to their determination by flame atomic absorption spectrometry. The adsorption mechanism of titled metals complexes on GO was investigated by using computational chemistry approach based on PM6 semi-empirical potential energy surface (PES). The effect of some parameters including pH, flow rate and volume of sample and type, volume and concentration of eluent, as well as the adsorption capacity of matrix ions on the recovery of Mn(II) and Fe(III) was investigated. The limit of detection was 145 and 162 ng L(-1) for Mn(II) and Fe(III), respectively. Calibration was linear over the range of 0.31-355 μg L(-1) for Mn(II) and 0.34-380 μg L(-1) for Fe(III) ions. The method was successfully applied for the determination of understudied ions in water, food and biological samples. PMID:24411390

  13. NiCrFe2-O4 ferrite nanoparticles and their composites with polypyrrole: synthesis, characterization and magnetic properties

    Indian Academy of Sciences (India)

    E H El-Ghazzawy; S N Alamri

    2015-08-01

    Nanocrystalline nickel chromium ferrite (NiCrFe2-O4, = 0.1, 0.2) have been prepared by the chemical co-precipitation method. Half of the samples have been sintered at 620°C and the other at 1175°C. Then polypyrrole (PPy)–NiCrFe2-O4 composites have been synthesized by polymerization of pyrrole monomer in the presence of NiCrFe2-O4 nanoparticles. The structure, morphology and magnetic properties of the samples have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectroscopy and vibrating sample magnetometer. Also, the initial magnetic permeability measurements as functions of temperature and frequency have been performed. The XRD and FT-IR studies have confirmed the well crystalline phase of ferrite nanoparticles, and the presence of amorphous PPy in the composite samples. The SEM and TEM images have obviously clarified the coating of ferrite nanoparticles by PPy in the composite samples. The hysteresis loop of the samples has proved that the samples are soft magnetic material because of their low coercivity.

  14. Identification, characterization, and high-performance liquid chromatography quantification of process-related impurities in vonoprazan fumarate.

    Science.gov (United States)

    Liu, Lei; Cao, Na; Ma, Xingling; Xiong, Kaihe; Sun, Lili; Zou, Qiaogen

    2016-04-01

    High-performance liquid chromatography analysis of vonoprazan fumarate, a novel proton pump inhibitor drug revealed six impurities. These were identified by liquid chromatography with mass spectrometry. Further, the structures of the impurities were confirmed by synthesis followed by characterization by mass spectrometry, NMR spectroscopy, and infrared spectroscopy. On the basis of these data and knowledge of the synthetic scheme of vonoprazan fumarate, the previously unknown impurity was identified as 1-[5-(2-fluorophenyl)-1-(pyridin-3-ylsulfonyl)-1H-pyrrol-3-yl]-N-methyldimethylamine, which is a new compound. The possible mechanisms by which these impurities were formed were also discussed. A high-performance liquid chromatography method was optimized in order to separate, selectively detect, and quantify all process-related impurities of vonoprazan fumarate. The presented method has been validated in terms of linearity, limits of detection, and quantification, and response factors and, therefore, is highly suitable for routine analysis of vonoprazan fumarate related substances as well as stability studies.

  15. Synthesis and partial characterization of a new low gap polymer: poly-2(5)-propenylidenepyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Hevesi, L. (Dept. of Chemistry, Facultes Universitaires N.-D. de la Paix, Namur (Belgium)); Proess, G. (Dept. of Chemistry, Facultes Universitaires N.-D. de la Paix, Namur (Belgium)); Lazarescu-Grigore, A. (Dept. of Chemistry, Facultes Universitaires N.-D. de la Paix, Namur (Belgium))

    1993-07-01

    As a result of previous studies on the reactivity of 1-selenoallyl cationic species with pyrroles, a synthetic scheme, based on the dramatic solvent effects on the regiochemistry of these reactions, has been devised for the preparation of the polymeric material 6 composed of alternating propenyl and pyrrole units. It is argued that oxidation of 6 using Ph[sub 3]CSbCl[sub 6] or DDQ produces the title compound 8 where every other alternating pyrrole ring should have a quinoid structure. In agreement with theoretical predictions of bandgap lowering by these quinoid structure units, preliminary measurements on the undoped and iodine-doped 8 gave conductivity values of [sigma]=1.1x10[sup -6] and [sigma]=(2.4-5.4)x10[sup -6] [Omega][sup -1] cm[sup -1], respectively. (orig.)

  16. Coordination of Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) with 2,5-hexanedione bis(thiosemicarbazone), HBTS: Crystal structure of cis-[Pd(HBTS)]Cl2 and 1-(2,5-dimethyl-1H-pyrrol-yl)-thiourea

    Science.gov (United States)

    Jeragh, Bakir; El-Asmy, Ahmed A.

    2014-09-01

    Metal complexes of Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Pd2+ or Pt2+ with 2,5-hexanedione bis(thiosemicarbazone), HBTS; have been prepared and spectroscopically investigated. The empirical formulae of the complexes were suggested based on the elemental analysis. Single crystal of Pd(II) has been solved to be cis-form of square-planar geometry by the X-ray crystallography. 1H and 13C NMR spectra have been recorded for HBTS, Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) complexes, in DMSO-d6, showing the mode of chelation. The ligand acts as a neutral or a binegative tetradentate (N2S2) or neutral bidentate on the basis of FT-IR. The magnetic moments and electronic spectra provide information about the geometry of the complexes which supported by calculating the ligand field parameters for the Co(II) and Fe(III) complexes. The Ni(II) complex has subnormal magnetic moment (0.71 BM) indicative of a mixed stereochemistry of square-planar and tetrahedral structure. [Cu(HBTS-2H)] measured 0.93 BM indicating high interaction between the copper centers. The ligand may be ordered at the top of the spectrochemical series which giving high ligand field splitting energy (10Dq = 17,900 cm-1 for Co2+ complex). The mass spectra of some complexes proved their stable chemical formulae while the TGA depicts the degradation steps and the final residue. In evaporating the mother liquor during the preparation of HBTS, new compound is obtained naming 1-(2,5-dimethyl-1H-pyrrol-yl)thiourea and its crystal was solved.

  17. Coordination of Fe(III), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) with 2,5-hexanedione bis(thiosemicarbazone), HBTS: crystal structure of cis-[Pd(HBTS)]Cl2 and 1-(2,5-dimethyl-1H-pyrrol-yl)-thiourea.

    Science.gov (United States)

    Jeragh, Bakir; El-Asmy, Ahmed A

    2014-09-15

    Metal complexes of Fe3+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Pd2+ or Pt2+ with 2,5-hexanedione bis(thiosemicarbazone), HBTS; have been prepared and spectroscopically investigated. The empirical formulae of the complexes were suggested based on the elemental analysis. Single crystal of Pd(II) has been solved to be cis-form of square-planar geometry by the X-ray crystallography. 1H and 13C NMR spectra have been recorded for HBTS, Zn(II), Cd(II), Hg(II), Pd(II) and Pt(II) complexes, in DMSO-d6, showing the mode of chelation. The ligand acts as a neutral or a binegative tetradentate (N2S2) or neutral bidentate on the basis of FT-IR. The magnetic moments and electronic spectra provide information about the geometry of the complexes which supported by calculating the ligand field parameters for the Co(II) and Fe(III) complexes. The Ni(II) complex has subnormal magnetic moment (0.71 BM) indicative of a mixed stereochemistry of square-planar and tetrahedral structure. [Cu(HBTS-2H)] measured 0.93 BM indicating high interaction between the copper centers. The ligand may be ordered at the top of the spectrochemical series which giving high ligand field splitting energy (10 Dq=17,900 cm(-1) for Co2+ complex). The mass spectra of some complexes proved their stable chemical formulae while the TGA depicts the degradation steps and the final residue. In evaporating the mother liquor during the preparation of HBTS, new compound is obtained naming 1-(2,5-dimethyl-1H-pyrrol-yl)thiourea and its crystal was solved. PMID:24813284

  18. Column solid phase extraction and flame atomic absorption spectrometric determination of manganese(II) and iron(III) ions in water, food and biological samples using 3-(1-methyl-1H-pyrrol-2-yl)-1H-pyrazole-5-carboxylic acid on synthesized graphene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Pourjavid, Mohammad Reza, E-mail: pourjavid@gmail.com [NFCRS, Nuclear Science and Technology Research Institute, P.O. Box 11365-8486, Tehran (Iran, Islamic Republic of); Sehat, Ali Akbari [Department of Analytical Chemistry, Faculty of Chemistry, University College of Science, University of Tehran, P.O. Box 14155-6455, Tehran (Iran, Islamic Republic of); Arabieh, Masoud; Yousefi, Seyed Reza; Hosseini, Majid Haji; Rezaee, Mohammad [NFCRS, Nuclear Science and Technology Research Institute, P.O. Box 11365-8486, Tehran (Iran, Islamic Republic of)

    2014-02-01

    A modified, selective, highly sensitive and accurate procedure for the determination of trace amounts of manganese and iron ions is established in the presented work. 3-(1-Methyl-1H-pyrrol-2-yl)-1H-pyrazole-5-carboxylic acid (MPPC) and graphene oxide (GO) were used in a glass column as chelating reagent and as adsorbent respectively prior to their determination by flame atomic absorption spectrometry. The adsorption mechanism of titled metals complexes on GO was investigated by using computational chemistry approach based on PM6 semi-empirical potential energy surface (PES). The effect of some parameters including pH, flow rate and volume of sample and type, volume and concentration of eluent, as well as the adsorption capacity of matrix ions on the recovery of Mn(II) and Fe(III) was investigated. The limit of detection was 145 and 162 ng L{sup −1} for Mn(II) and Fe(III), respectively. Calibration was linear over the range of 0.31–355 μg L{sup −1} for Mn(II) and 0.34–380 μg L{sup −1} for Fe(III) ions. The method was successfully applied for the determination of understudied ions in water, food and biological samples. - Highlights: • We use synthesized graphene oxide as adsorbent for SPE of Mn(II) and Fe(III) ions. • Adsorption mechanism was investigated by PM6 semi-empirical potential energy surface. • Detection limits were 145 and 162 ng L{sup −1} for Mn and Fe, respectively. • The preconcentration factor was 325 and sample flow rate is 8 mL min{sup −1}. • It was successfully applied to the determination of Mn and Fe ions in real samples.

  19. Full characterization of polypyrrole thin films electrosynthesized in room temperature ionic liquids, water or acetonitrile

    International Nuclear Information System (INIS)

    Highlights: • Polypyrrole films were electrodeposited from three room temperature ionic liquids. • Polymer films were characterized using many surface analysis techniques. • The incorporation of anions and/or cations inside the polymer films was evidenced. • The influence of the ionic liquid on the polymer properties was deeply studied. - Abstract: Pyrrole was electrochemically oxidized in two conventional media (water and acetonitrile) and in three room temperature ionic liquids: 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, and 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide. Infrared and Raman Spectroscopies confirmed the formation of polypyrrole by electropolymerization but were unable to demonstrate the presence of anions in the polymer films. The use of ionic liquids as growth media resulted in polymer films having a good electrochemical activity. The difference of activity from one polymer film to the other was mainly attributed to the difference of viscosity between the solvents used. The morphological features of the polypyrrole films were also fully studied. Profilometric measurements demonstrated that polymer films grown, at the same potential, in ionic liquids were thinner and had a smaller roughness than those grown in other solvents. Atomic Force Microscopy showed that polypyrrole films had nearly similar micrometric nodular structure whatever the growth medium even if some differences of porosity and homogeneity were observed using Scanning Electron Microscopy. The incorporation of counter-anions at the top surface of the films was finally evidenced by X-ray Photoelectron Spectroscopy. These anions were also incorporated inside the polymer film with a uniform distribution as shown by Glow Discharge Optical Emission Spectroscopy

  20. Practical materials characterization

    CERN Document Server

    2014-01-01

    Presents cross-comparison between materials characterization techniquesIncludes clear specifications of strengths and limitations of each technique for specific materials characterization problemFocuses on applications and clear data interpretation without extensive mathematics

  1. Waste Characterization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Vigil-Holterman, Luciana R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Naranjo, Felicia Danielle [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-02

    This report discusses ways to classify waste as outlined by LANL. Waste Generators must make a waste determination and characterize regulated waste by appropriate analytical testing or use of acceptable knowledge (AK). Use of AK for characterization requires several source documents. Waste characterization documentation must be accurate, sufficient, and current (i.e., updated); relevant and traceable to the waste stream’s generation, characterization, and management; and not merely a list of information sources.

  2. Sequential ultrasonic extraction of a Chinese coal and characterization of nitrogen-containing compounds in the extracts using high-performance liquid chromatography with mass spectrometry.

    Science.gov (United States)

    Xia, Jun-Liu; Fan, Xing; You, Chun-Yan; Wei, Xian-Yong; Zhao, Yun-Peng; Cao, Jing-Pei

    2016-07-01

    Dongming lignite was sequentially extracted with petroleum ether, carbon disulfide, methanol, acetone, and isometric carbon disulfide/acetone mixed solvent at room temperature to afford extracts 1-5, respectively. High-performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry was used to separate and characterize heteroatomic species in the extracts at molecular level. Molecular mass of compounds in the extracts is mainly distributed from 300 to 800 u, and the relative abundance of compounds with molecular mass over 800 u in the carbon disulfide extract is 135 times of that in the petroleum ether extract. The acetone extract has the highest relative abundance for organonitrogen compounds. Double bond equivalence numbers of detected species indicate that most of the organonitrogen compounds contain N-heterocyclic aromatic rings, including pyridine, quinoline and pyrrole. Some organonitrogen isomers in Dongming lignite were separated and identified by high-performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry, and the corresponding structural information was proposed.

  3. Hybride magnetic nanostructure based on amino acids functionalized polypyrrole

    Energy Technology Data Exchange (ETDEWEB)

    Nan, Alexandrina, E-mail: alexandrina.nan@itim-cj.ro; Bunge, Alexander; Turcu, Rodica [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat, 400293 Cluj-Napoca (Romania)

    2015-12-23

    Conducting polypyrrole is especially promising for many commercial applications because of its unique optical, electric, thermal and mechanical properties. We report the synthesis and characterization of novel pyrrole functionalized monomers and core-shell hybrid nanostructures, consisting of a conjugated polymer layer (amino acids functionalized pyrrole copolymers) and a magnetic nanoparticle core. For functionalization of the pyrrole monomer we used several amino acids: tryptophan, leucine, phenylalanine, serine and tyrosine. These amino acids were linked via different types of hydrophobic linkers to the nitrogen atom of the pyrrole monomer. The magnetic core-shell hybrid nanostructures are characterized by various methods such as FTIR spectroscopy, transmission electron microscopy (TEM) and magnetic measurements.

  4. Hybride magnetic nanostructure based on amino acids functionalized polypyrrole

    Science.gov (United States)

    Nan, Alexandrina; Bunge, Alexander; Turcu, Rodica

    2015-12-01

    Conducting polypyrrole is especially promising for many commercial applications because of its unique optical, electric, thermal and mechanical properties. We report the synthesis and characterization of novel pyrrole functionalized monomers and core-shell hybrid nanostructures, consisting of a conjugated polymer layer (amino acids functionalized pyrrole copolymers) and a magnetic nanoparticle core. For functionalization of the pyrrole monomer we used several amino acids: tryptophan, leucine, phenylalanine, serine and tyrosine. These amino acids were linked via different types of hydrophobic linkers to the nitrogen atom of the pyrrole monomer. The magnetic core-shell hybrid nanostructures are characterized by various methods such as FTIR spectroscopy, transmission electron microscopy (TEM) and magnetic measurements.

  5. Hybride magnetic nanostructure based on amino acids functionalized polypyrrole

    International Nuclear Information System (INIS)

    Conducting polypyrrole is especially promising for many commercial applications because of its unique optical, electric, thermal and mechanical properties. We report the synthesis and characterization of novel pyrrole functionalized monomers and core-shell hybrid nanostructures, consisting of a conjugated polymer layer (amino acids functionalized pyrrole copolymers) and a magnetic nanoparticle core. For functionalization of the pyrrole monomer we used several amino acids: tryptophan, leucine, phenylalanine, serine and tyrosine. These amino acids were linked via different types of hydrophobic linkers to the nitrogen atom of the pyrrole monomer. The magnetic core-shell hybrid nanostructures are characterized by various methods such as FTIR spectroscopy, transmission electron microscopy (TEM) and magnetic measurements

  6. Materials Characterization Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Materials Characterization Facility enables detailed measurements of the properties of ceramics, polymers, glasses, and composites. It features instrumentation...

  7. Composites Characterization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The purpose of the Composites Characterization Laboratory is to investigate new and/or modified matrix materials and fibers for advanced composite applications both...

  8. 4-Acetyl-1H-pyrrole-2-carbaldehyde

    Directory of Open Access Journals (Sweden)

    Tao Sun

    2012-10-01

    Full Text Available The title compound, C7H7NO2, was synthesized via a one-pot Vilsmeier–Haack and subsequent Friedel–Crafts reaction. The pyrazole ring makes dihedral angles of 4.50 (9 and 2.06 (8°, respectively, with the aldehyde and acetyl groups. In the crystal, classical N—H...O hydrogen bonds and weak C—H...O interactions assemble the molecules into a chain along the b axis.

  9. Characterization of revenue equivalence

    NARCIS (Netherlands)

    Heydenreich, B.; Müller, R.; Uetz, M.J.; Vohra, R.

    2009-01-01

    The property of an allocation rule to be implementable in dominant strategies by a unique payment scheme is called revenue equivalence. We give a characterization of revenue equivalence based on a graph theoretic interpretation of the incentive compatibility constraints. The characterization holds f

  10. Isocyanide or nitrosyl complexation to hemes with varying tethered axial base ligand donors: synthesis and characterization.

    Science.gov (United States)

    Sharma, Savita K; Kim, Hyun; Rogler, Patrick J; A Siegler, Maxime; Karlin, Kenneth D

    2016-09-01

    A series of ferrous-heme 2,6-dimethylphenyl isocyanide (DIMPI) and ferrous-heme mononitrosyl complexes have been synthesized and characterized. The heme portion of the complexes studied is varied with respect to the nature of the axial ligand, including complexes, where it is covalently tethered to the porphyrinate periphery. Reduced heme complexes, [(F8)Fe(II)], [(P(Py))Fe(II)], [(P(Im))Fe(II)], and [(P(ImH))Fe(II)], where F8 = tetrakis(2,6-difluorophenyl)-porphyrinate and P(Py), P(Im), and P(ImH) are partially fluorinated tetraaryl porphyrinates with covalently appended axial base pyridyl/imidazolyl or histamine moieties, were employed; P(ImH) is a new construct. Room temperature addition of DIMPI to these iron(II) complexes affords the bis-isocyanide species [(F8)Fe(II)-(DIMPI)2] in the case of [(F8)Fe(II)], while for the other hemes, mono-DIMPI compounds are obtained, [(P(Py))Fe(II)-(DIMPI)] [(2)-DIMPI], [(P(Im))Fe(II)-(DIMPI)] [(3)-DIMPI], and [(P(ImH))Fe(II)-(DIMPI)] [(4)-DIMPI]. The structures of complexes (3)-DIMPI and (4)-DIMPI have been determined by single crystal X-ray crystallography, where interesting H…F(porphryinate aryl group) interactions are observed. (19)F-NMR spectra determined for these complexes suggest that H…F(porphyrinate aryl groups) attractions also occur in solution, the H atom coming either from the DIMPI methyl groups or from a porphyinate axial base imidazole or porphyrinate pyrrole. Similarly, we have used nitrogen monoxide to generate ferrous-nitrosyl complexes, a five-coordinate species for F8, [(F8)Fe(II)-(NO)], or low-spin six-coordinate compounds [(P(Py))Fe(II)-(NO)], [(P(Im))Fe(II)-(NO)], and [(P(ImH))Fe(II)-(NO)]. The DIMPI and mononitrosyl complexes have also been characterized using UV-Vis, IR, (1)H-NMR, and EPR spectroscopies. PMID:27350154

  11. Novel conductive polypyrrole/zinc oxide/chitosan bionanocomposite: synthesis, characterization, antioxidant, and antibacterial activities

    Directory of Open Access Journals (Sweden)

    Ebrahimiasl S

    2014-12-01

    Full Text Available Saeideh Ebrahimiasl,1,2 Azmi Zakaria,3 Anuar Kassim,4 Sri Norleha Basri4 1Department of Nanotechnology, Institute of Advanced Technology, Universiti Putra Malaysia, Serdang, Malaysia; 2Department of Chemistry, Ahar Branch, Islamic Azad University, Ahar, Iran; 3Department of Physics, Universiti Putra Malaysia, Serdang, Malaysia; 4Department of Chemistry, Universiti Putra Malaysia, Serdang, Malaysia Abstract: An antibacterial and conductive bionanocomposite (BNC film consisting of polypyrrole (Ppy, zinc oxide (ZnO nanoparticles (NPs, and chitosan (CS was electrochemically synthesized on indium tin oxide (ITO glass substrate by electrooxidation of 0.1 M pyrrole in aqueous solution containing appropriate amounts of ZnO NPs uniformly dispersed in CS. This method enables the room temperature electrosynthesis of BNC film consisting of ZnO NPs incorporated within the growing Ppy/CS composite. The morphology of Ppy/ZnO/CS BNC was characterized by scanning electron microscopy. ITO–Ppy/CS and ITO–Ppy/ZnO/CS bioelectrodes were characterized using the Fourier transform infrared technique, X-ray diffraction, and thermogravimetric analysis. The electrical conductivity of nanocomposites was investigated by a four-probe method. The prepared nanocomposites were analyzed for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl assay. The results demonstrated that the antioxidant activity of nanocomposites increased remarkably by addition of ZnO NPs. The electrical conductivity of films showed a sudden decrease for lower weight ratios of ZnO NPs (5 wt%, while it was increased gradually for higher ratios (10, 15, and 20 wt%. The nanocomposites were analyzed for antibacterial activity against Gram-positive and Gram-negative bacteria. The results indicated that the synthesized BNC is effective against all of the studied bacteria, and its effectiveness is higher for Pseudomonas aeruginosa. The thermal stability and physical properties of BNC films were

  12. Metric characterizations II

    CERN Document Server

    Blecher, David P

    2012-01-01

    The present paper is a sequel to our paper "Metric characterization of isometries and of unital operator spaces and systems". We characterize certain common objects in the theory of operator spaces (unitaries, unital operator spaces, operator systems, operator algebras, and so on), in terms which are purely linear-metric, by which we mean that they only use the vector space structure of the space and its matrix norms. In the last part we give some characterizations of operator algebras (which are not linear-metric in our strict sense described in the paper).

  13. Panel 3 - characterization

    Energy Technology Data Exchange (ETDEWEB)

    Erck, R.A.; Erdemir, A.; Janghsing Hsieh; Lee, R.H.; Xian Zheng Pan; Deming Shu [Argonne National Lab., IL (United States); Feldman, A. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Glass, J.T. [North Carolina State Univ., Raleigh (United States); Kleimer, R. [Coors Ceramics Co., Golden, CO (United States); Lawton, E.A. [JPL/Caltech, Pasadena, CA (United States); McHargue, C.J. [Univ. of Tennessee, Knoxville (United States)

    1993-01-01

    The task of this panel was to identify and prioritize needs in the area of characterization of diamond and diamond-like-carbon (DLC) films for use in the transportation industry. Until recent advances in production of inexpensive films of diamonds and DLC, it was not feasible that these materials could be mass produced. The Characterization Panel is restricting itself to identifying needs in areas that would be most useful to manufacturers and users in producing and utilizing diamond and DLC coatings in industry. These characterization needs include in-situ monitoring during growth, relation of structure to performance, and standards and definitions.

  14. Studies of the biogenic amine transporters. VI. Characterization of a novel cocaine binding site, identified with [125I]RTI-55, in membranes prepared from whole rat brain minus caudate.

    Science.gov (United States)

    Rothman, R B; Silverthorn, M L; Baumann, M H; Goodman, C B; Cadet, J L; Matecka, D; Rice, K C; Carroll, F I; Wang, J B; Uhl, G R

    1995-07-01

    Previous studies showed that the cocaine analog [125I]RTI-55 labels dopamine and serotonergic (5-HT) biogenic amine transporters (BATs) with high affinity. Here we characterized [125I]RTI-55 binding to membranes prepared from whole rat brain minus the caudate nuclei. Paroxetine (50 nM) was used to block [125I]RTI-55 binding to 5-HT transporter sites. Initial experiments identified drugs that displaced [125I]RTI-55 binding with moderately low slope factors. Binding surface analysis of the interaction of 3 beta-(4-chlorophenyl)tropan-2 beta-carboxylic acid phenyl ester hydrochloride (RTI-113) and 3 beta-(4-iodophenyl)tropan-2 beta-carboxylic acid phenyl ester hydrochloride (RTI-122) with [125I]RTI-55 binding sites readily resolved two binding sites for [125I]RTI-55 with Kd values of 0.44 nM and 17 nM and Bmax values of 31 and 245 fmol/mg protein. Potent 5-HT and noradrenergic uptake inhibitors had low affinity for both sites. Whereas cocaine, CFT and WIN35,065-2 were 6.0-, 25- and 14-fold selective for the first site, benztropine, PCP and the novel pyrrole, (+-)-(2RS,3aSR,8bRS)-1,2,3,3a,4,8b-hexahydro- 2-benzyl-1-methylindeno-[1,2-b]pyrrole resorcylate [(+-)-HBMP, formerly called (+-)-RTI-4793-14], were moderately selective for the second site. A single binding site with the characteristics of site 1 was resolved using COS cells transiently expressing the cloned rat dopamine transporter. Lesion studies with 6-hydroxydopamine and 5,7-dihydroxytryptamine were conducted to test the hypothesis that site 1 and site 2 are physically distinct. The data showed that these neurotoxins differentially decreased [125I]RTI-55 binding to sites 1 and 2. The differential distribution of sites 1 and 2 in rat brain provides further support for this hypothesis. Viewed collectively, these data show that [125I]RTI-55 labels a novel binding site in rat brain membranes, termed DATsite2, which is not associated with the classic dopamine, serotonin or norepinephrine transporters.

  15. A characterization of maximin

    NARCIS (Netherlands)

    Bosmans, K.G.M.; Ooghe, E.

    2013-01-01

    We characterize maximin on the basis of anonymity, continuity, weak Pareto and weak Hammond equity. In contrast to the standard Hammond equity axiom, weak Hammond equity supports only utility transfers that unambiguously diminish overall inequality.

  16. How to characterize disorder

    Science.gov (United States)

    Egami, T.

    2016-05-01

    Researchers working on nuclear materials encounter disorder in the atomic structure all the time, usually caused by irradiation. The nature of disorder varies widely, from lattice defects to amorphous phase formation. Generally it is not easy to characterize the state of disorder with the accuracy necessary to elucidate the properties caused by structural disorder. However, owing to advances in the tools of characterization and rapid rise in computer power, significant progress has been made in characterizing structural disorder. We discuss how to describe and determine the structure and dynamics of disordered materials using scattering measurements and modeling. Lattice defects caused by irradiation usually has negative effects on properties, but glasses and highly disordered materials can be irradiation resistant, and could be useful as nuclear materials. Characterizing and controlling disorder is becoming an important endeavor in the field of nuclear materials.

  17. Characterization of nanomaterials

    International Nuclear Information System (INIS)

    This paper provides an overview of the main techniques used for the characterization of nanomaterials. The knowledge of some basic characteristics, inherent morphology, microstructure, the distribution phase and chemical composition, it is essential to evaluate the functional properties of nanomaterials and make predictions about their behavior in operation. For the characterization of nanomaterials can be used in both imaging techniques both analytic techniques. Among the first found wide application optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Among the latter some types of spectroscopy and X-ray diffraction (XRD). For each type of material to characterize the choice of the most appropriate technique it is based on the type of details that you want to obtain, and on their scale. In this paper are discussed in detail some examples and the main methods used for the characterization of nanomaterials.

  18. Characterization of Revenue Equivalence

    OpenAIRE

    Heydenreich, B.; Müller, R.J.; Uetz, M.J.; R. Vohra

    2008-01-01

    The property of an allocation rule to be implementable in dominant strategies by a unique payment scheme is called \\emph{revenue equivalence}. In this paper we give a characterization of revenue equivalence based on a graph theoretic interpretation of the incentive compatibility constraints. The characterization holds for any (possibly infinite) outcome space and many of the known results are immediate consequences. Moreover, revenue equivalence can be identified in cases where existing theor...

  19. Site characterization handbook

    Energy Technology Data Exchange (ETDEWEB)

    1988-06-01

    This Handbook discusses both management and technical elements that should be considered in developing a comprehensive site characterization program. Management elements typical of any project of a comparable magnitude and complexity are combined with a discussion of strategies specific to site characterization. Information specific to the technical elements involved in site characterization is based on guidance published by the Nuclear Regulatory Commission (NRC) with respect to licensing requirements for LLW disposal facilities. The objective of this Handbook is to provide a reference for both NRC Agreement States and non-Agreement States for use in developing a comprehensive site characterization program that meets the specific objectives of the State and/or site developer/licensee. Each site characterization program will vary depending on the objectives, licensing requirements, schedules/budgets, physical characteristics of the site, proposed facility design, and the specific concerns raised by government agencies and the public. Therefore, the Handbook is not a prescriptive guide to site characterization. 18 refs., 6 figs.

  20. Chemical and morphological characterization of TSP and PM2.5 by SEM-EDS, XPS and XRD collected in the metropolitan area of Monterrey, Mexico

    Science.gov (United States)

    González, Lucy T.; Rodríguez, F. E. Longoria; Sánchez-Domínguez, M.; Leyva-Porras, C.; Silva-Vidaurri, L. G.; Acuna-Askar, Karim; Kharisov, B. I.; Villarreal Chiu, J. F.; Alfaro Barbosa, J. M.

    2016-10-01

    Total suspended particles (TSP) and particles smaller than 2.5 μm (PM2.5) were collected at four sites in the metropolitan area of Monterrey (MAM) in Mexico. The samples were characterized by X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and Scanning Electron Microscopy (SEM). In order to determine the possible sources of emissions of atmospheric particulate matter, a principal component analysis (PCA) was performed. The XRD results showed that the major crystalline compounds found in the TPS were CaCO3 and SiO2; while in the PM2.5 CaSO4 was found. The XPS analysis showed that the main elements found on the surface of the particles were C, O, Si, Ca, S, and N. The deconvolution carried out on the high-resolution spectra for C1s, S2p and N1s, showed that the aromatics, sulfates and pyrrolic-amides were the main groups contributing to the signal of these elements, respectively. The C-rich particles presented a spherical morphology, while the Ca- and Si-based particles mostly showed a prismatic shape. The PCA analysis together with the results obtained from the characterization techniques, suggested that the main contributors to the CaCO3 particles collected in the PM were most probably produced and emitted into the atmosphere by local construction industries and exploitation of rich-deposits of calcite. Meanwhile, the SiO2 found in the MAM originated from the suspension of geological material abundant in the region, and the carbon particles were mainly produced by the combustion of fossil fuels.

  1. Space Solar Cell Characterization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Measures, characterizes, and analyzes photovoltaic materials and devices. The primary focus is the measurement and characterization of solar cell response...

  2. Site characterization plan:

    International Nuclear Information System (INIS)

    The Yucca Mountain site in Nevada is one of three candidate sites for the first geologic repository for radioactive waste. On May 28, 1986, it was recommended for detailed study in a program of site characterization. This site characterization plan (SCP) has been prepared in acordance with the requirements of the Nuclear Waste Policy Act to summarize the information collected to date about the geologic conditions at the site;to describe the conceptual designs for the repository and the waste package and to present the plans for obtaining the geologic information necessary to demonstrate the suitability of the site for a repository, to design the repository and the waste package, to prepare an environmental impact statement, and to obtain from the US Nuclear Regulatory Commission (NRC) an authorization to construct the repository. This introduction begins with a brief section on the process for siting and eveloping a repository, followed by a discussion of the pertinent legislation and regulations. A description of site characterization is presented next;it describes the facilities to be constructed for the site characterization program and explains the principal activities to be conducted during the program. Finally, the purpose, content, organizing prinicples, and organization of this site characterization plan are outlined, and compliance with applicable regulations is discussed. 880 refs., 130 figs., 25 tabs

  3. Site characterization plan:

    International Nuclear Information System (INIS)

    The Yucca Mountain site in Nevada is one of three candidate sites for the first geologic repository for radioactive waste. On May 28, 1986, it was recommended for detailed study in a program of site characterization. This site characterization plan (SCP) has been prepared in accordance with the requirements of the Nuclear Waste Policy Act to summarize the information collected to date about the geologic conditions at the site;to describe the conceptual designs for the repository and the waste package;and to present the plans for obtaining the geologic information necessary to demonstrate the suitability of the site for repository, to design the repository and the waste package, to prepare an environmental impact statement, and to obtain from the US Nuclear Regulatory Commission (NRC) an authorization to construct the repository. This introduction begins with a brief section on the process for siting and developing a repository, followed by a discussion of the pertinent legislation and regulations. A description of site characterization is presented next;it describes the facilities to be constructed for the site characterization program and explains the principal activities to be conducted during the program. Finally, the purpose, content, organizing principles, and organization of this site characterization plan are outlined, and compliance with applicable regulations is discussed

  4. Tank characterization reference guide

    International Nuclear Information System (INIS)

    Characterization of the Hanford Site high-level waste storage tanks supports safety issue resolution; operations and maintenance requirements; and retrieval, pretreatment, vitrification, and disposal technology development. Technical, historical, and programmatic information about the waste tanks is often scattered among many sources, if it is documented at all. This Tank Characterization Reference Guide, therefore, serves as a common location for much of the generic tank information that is otherwise contained in many documents. The report is intended to be an introduction to the issues and history surrounding the generation, storage, and management of the liquid process wastes, and a presentation of the sampling, analysis, and modeling activities that support the current waste characterization. This report should provide a basis upon which those unfamiliar with the Hanford Site tank farms can start their research

  5. Characterization of leaky faults

    International Nuclear Information System (INIS)

    Leaky faults provide a flow path for fluids to move underground. It is very important to characterize such faults in various engineering projects. The purpose of this work is to develop mathematical solutions for this characterization. The flow of water in an aquifer system and the flow of air in the unsaturated fault-rock system were studied. If the leaky fault cuts through two aquifers, characterization of the fault can be achieved by pumping water from one of the aquifers, which are assumed to be horizontal and of uniform thickness. Analytical solutions have been developed for two cases of either a negligibly small or a significantly large drawdown in the unpumped aquifer. Some practical methods for using these solutions are presented. 45 refs., 72 figs., 11 tabs

  6. Geostatistics for fracture characterization

    International Nuclear Information System (INIS)

    As the critical role of fractures has become more apparent in fluid flow and contaminant transport studies, the characterization of fracture networks has received considerable attention in a wide variety of applications such as nuclear waste repository design. The application of geostatistics to fracture characterization has traditionally involved modelling fractures as thin disks; assumptions about the frequency, orientation, length and width of these disks allow the construction of a 3D model of the fracture network. This paper examines alternatives whose statistical parameters are more relevant for contaminant transport studies and are also easier to infer and validate. A new algorithm for conditional simulation is presented, one that is able to honor multipoint statistics through annealing. By honoring statistics that capture with two-point spatial convariances, this algorithm offers an important new tool not only for the specific problem of fracture characterization but also for the more general problem of spatial simulation

  7. Tank characterization reference guide

    Energy Technology Data Exchange (ETDEWEB)

    De Lorenzo, D.S.; DiCenso, A.T.; Hiller, D.B.; Johnson, K.W.; Rutherford, J.H.; Smith, D.J. [Los Alamos Technical Associates, Kennewick, WA (United States); Simpson, B.C. [Westinghouse Hanford Co., Richland, WA (United States)

    1994-09-01

    Characterization of the Hanford Site high-level waste storage tanks supports safety issue resolution; operations and maintenance requirements; and retrieval, pretreatment, vitrification, and disposal technology development. Technical, historical, and programmatic information about the waste tanks is often scattered among many sources, if it is documented at all. This Tank Characterization Reference Guide, therefore, serves as a common location for much of the generic tank information that is otherwise contained in many documents. The report is intended to be an introduction to the issues and history surrounding the generation, storage, and management of the liquid process wastes, and a presentation of the sampling, analysis, and modeling activities that support the current waste characterization. This report should provide a basis upon which those unfamiliar with the Hanford Site tank farms can start their research.

  8. Monodisperse metal nanoparticle catalysts on silica mesoporous supports: synthesis, characterizations, and catalytic reactions

    Energy Technology Data Exchange (ETDEWEB)

    Somorjai, G.A.

    2009-09-14

    The design of high performance catalyst achieving near 100% product selectivity at maximum activity is one of the most important goals in the modern catalytic science research. To this end, the preparation of model catalysts whose catalytic performances can be predicted in a systematic and rational manner is of significant importance, which thereby allows understanding of the molecular ingredients affecting the catalytic performances. We have designed novel 3-dimensional (3D) high surface area model catalysts by the integration of colloidal metal nanoparticles and mesoporous silica supports. Monodisperse colloidal metal NPs with controllable size and shape were synthesized using dendrimers, polymers, or surfactants as the surface stabilizers. The size of Pt, and Rh nanoparticles can be varied from sub 1 nm to 15 nm, while the shape of Pt can be controlled to cube, cuboctahedron, and octahedron. The 3D model catalysts were generated by the incorporation of metal nanoparticles into the pores of mesoporous silica supports via two methods: capillary inclusion (CI) and nanoparticle encapsulation (NE). The former method relies on the sonication-induced inclusion of metal nanoparticles into the pores of mesoporous silica, whereas the latter is performed by the encapsulation of metal nanoparticles during the hydrothermal synthesis of mesoporous silica. The 3D model catalysts were comprehensively characterized by a variety of physical and chemical methods. These catalysts were found to show structure sensitivity in hydrocarbon conversion reactions. The Pt NPs supported on mesoporous SBA-15 silica (Pt/SBA-15) displayed significant particle size sensitivity in ethane hydrogenolysis over the size range of 1-7 nm. The Pt/SBA-15 catalysts also exhibited particle size dependent product selectivity in cyclohexene hydrogenation, crotonaldehyde hydrogenation, and pyrrole hydrogenation. The Rh loaded SBA-15 silica catalyst showed structure sensitivity in CO oxidation reaction. In

  9. Characterizing teleportation in optics

    OpenAIRE

    Ralph, T. C.; Polkinghorne, R. E. S.; Lam, P.K.

    1999-01-01

    We discuss the characterization of continuous variable, optical quantum teleportation in terms of the two quadrature signal transfer and conditional variances between the input and output states. We derive criteria which clearly define the classical limits and highlight interesting operating points which are not obvious from a calculation of the fidelity of the teleportation alone.

  10. Characterization of Bacillus cereus

    NARCIS (Netherlands)

    Wijnands LM; Dufrenne JB; Leusden FM; MGB

    2002-01-01

    Bacillus cereus is a ubiquitary microorganism that may cause food borne disease. Pathogenicity, however, depends on various characteristics such as the ability to form (entero)-toxin(s) that can not be detected by microbiological methods. Further characterization of pathogenic properties is not only

  11. Characterization of revenue equivalence

    NARCIS (Netherlands)

    Heydenreich, Birgit; Müller, Rudolf; Uetz, Marc; Vohra, Rakesh

    2008-01-01

    The property of an allocation rule to be implementable in dominant strategies by a unique payment scheme is called \\emph{revenue equivalence}. In this paper we give a characterization of revenue equivalence based on a graph theoretic interpretation of the incentive compatibility constraints. The cha

  12. Characterization of Photovoltaic Generators

    Science.gov (United States)

    Boitier, V.; Cressault, Y.

    2011-01-01

    This paper discusses photovoltaic panel systems and reviews their electrical properties and use in several industrial fields. We explain how different photovoltaic panels may be characterized by undergraduate students at university using simple methods to retrieve their electrical properties (power, current and voltage) and compare these values…

  13. Preparation and characterization of a composite hydrogel with graphene oxide as an acid catalyst.

    Science.gov (United States)

    Jiang, Ting; Sui, Zhu-Yin; Yang, Quan-Sheng; Zhang, Xuetong; Han, Bao-Hang

    2015-04-28

    In this study, a facile method for synthesizing a novel graphene oxide/pyrrole-formaldehyde (GOP-1) composite hydrogel was developed via in situ polymerization of pyrrole and formaldehyde in the presence of graphene oxide sheets without any additional catalyst. During the polymerization, graphene oxide can act as a two-dimensional template to regulate the aggregation state of polymer and as an acid catalyst to accelerate the reaction rate of pyrrole and formaldehyde. The morphology and microstructure were investigated by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction, respectively. The chemical properties were analyzed via X-ray photoelectron spectroscopy, infrared spectroscopy, and Raman spectroscopy. The freeze-dried GOP-1 composite hydrogel exhibited a large specific surface area, high nitrogen content, and three-dimensional network structure. Based on the above features, the freeze-dried GOP-1 composite hydrogel used as a gas adsorbent showed a high carbon dioxide uptake capacity at 1.0 bar and 273 K (11.1 wt%), in sharp contrast to that of graphene oxide (7.4 wt%). Furthermore, the as-prepared composite hydrogel may possess attractive potential in the fields of electrode material, tissue engineering, and water treatment. PMID:25760407

  14. Signal integrity characterization techniques

    CERN Document Server

    Bogatin, Eric

    2009-01-01

    "Signal Integrity Characterization Techniques" addresses the gap between traditional digital and microwave curricula all while focusing on a practical and intuitive understanding of signal integrity effects within the data transmission channel. High-speed interconnects such as connectors, PCBs, cables, IC packages, and backplanes are critical elements of differential channels that must be designed using today's most powerful analysis and characterization tools.Both measurements and simulation must be done on the device under test, and both activities must yield data that correlates with each other. Most of this book focuses on real-world applications of signal integrity measurements - from backplane for design challenges to error correction techniques to jitter measurement technologies. The authors' approach wisely addresses some of these new high-speed technologies, and it also provides valuable insight into its future direction and will teach the reader valuable lessons on the industry.

  15. Site characterization techniques

    Science.gov (United States)

    U.S. Geological Survey

    1995-01-01

    Geoelectrical methods have been used since the 1920's to search for metallic ore deposits. During the last decade, traditional mining geophysical techniques have been adapted for environmental site characterization. Geoelectrical geophysics is now a well developed engineering specialty, with different methods to focus both on a range of targets and on depths below the surface. Most methods have also been adapted to borehole measurements.

  16. Proton Beam Energy Characterization

    OpenAIRE

    Marus, Lauren A.; Engle, J.W.; John, K. D.; Birnbaum, E. R.; Nortier, F. M.

    2015-01-01

    Introduction The Los Alamos Isotope Production Facility (IPF) is actively engaged in the development of isotope production technologies that can utilize its 100 MeV proton beam. Characterization of the proton beam energy and current is vital for optimizing isotope production and accurately conducting research at the IPF. Motivation In order to monitor beam intensity during research irradiations, aluminum foils are interspersed in experimental stacks. A theoretical yield of 22Na from...

  17. A Characterization of Polynomials

    DEFF Research Database (Denmark)

    Andersen, Kurt Munk

    1996-01-01

    Given the problem:which functions f(x) are characterized by a relation of the form:f[x1,x2,...,xn]=h(x1+x2+...+xn), where n>1 and h(x) is a given function? Here f[x1,x2,...,xn] denotes the divided difference on n points x1,x2,...,xn of the function f(x).The answer is: f(x) is a polynomial of degree...

  18. Asexuality: Classification and characterization

    OpenAIRE

    Prause, Nicole; Graham, Cynthia A.

    2007-01-01

    This is a post-print version of the article. The official published version can be obtaineed at the link below. The term “asexual” has been defined in many different ways and asexuality has received very little research attention. In a small qualitative study (N = 4), individuals who self-identified as asexual were interviewed to help formulate hypotheses for a larger study. The second larger study was an online survey drawn from a convenience sample designed to better characterize asexual...

  19. Characterizing Modular Ontologies

    OpenAIRE

    Ben Abbès, Sarra; Scheuermann, Andreas; Meilender, Thomas; D'Aquin, Mathieu

    2012-01-01

    Since large monolithic ontologies are di cult to handle and reuse ontology modularization has attracted increasing attention. Several approaches and tools have been developed to support ontology modularization. Despite these e orts, a lack of knowledge about characteristics of modularly organized ontologies prevents further development. This work aims at characterizing modular ontologies. Therefore, we analyze existing modular ontologies by applying selected metrics from software engineering ...

  20. Unary Resolution: Characterizing Ptime.

    OpenAIRE

    Seiller, Thomas; Aubert, Clément; Bagnol, Marc

    2016-01-01

    We give a characterization of deterministic polynomial time computation based on an algebraic structure called the resolution semiring, whose elements can be understood as logic programs or sets of rewriting rules over first-order terms. This construction stems from an interactive interpretation of the cut-elimination procedure of linear logic known as the geometry of interaction.This framework is restricted to terms (logic programs, rewriting rules) using only unary symbols, and this restric...

  1. Probabilistic Logical Characterization

    DEFF Research Database (Denmark)

    Hermanns, Holger; Parma, Augusto; Segala, Roberto;

    2011-01-01

    Probabilistic automata exhibit both probabilistic and non-deterministic choice. They are therefore a powerful semantic foundation for modeling concurrent systems with random phenomena arising in many applications ranging from artificial intelligence, security, systems biology to performance model...... modeling. Several variations of bisimulation and simulation relations have proved to be useful as means to abstract and compare different automata. This paper develops a taxonomy of logical characterizations of these relations on image-finite and image-infinite probabilistic automata....

  2. On Characterizing Particle Shape

    Science.gov (United States)

    Ennis, Bryan J.; Rickman, Douglas; Rollins, A. Brent; Ennis, Brandon

    2014-01-01

    It is well known that particle shape affects flow characteristics of granular materials, as well as a variety of other solids processing issues such as compaction, rheology, filtration and other two-phase flow problems. The impact of shape crosses many diverse and commercially important applications, including pharmaceuticals, civil engineering, metallurgy, health, and food processing. Two applications studied here include the dry solids flow of lunar simulants (e.g. JSC-1, NU-LHT-2M, OB-1), and the flow properties of wet concrete, including final compressive strength. A multi-dimensional generalized, engineering method to quantitatively characterize particle shapes has been developed, applicable to both single particle orientation and multi-particle assemblies. The two-dimension, three dimension inversion problem is also treated, and the application of these methods to DEM model particles will be discussed. In the case of lunar simulants, flow properties of six lunar simulants have been measured, and the impact of particle shape on flowability - as characterized by the shape method developed here -- is discussed, especially in the context of three simulants of similar size range. In the context of concrete processing, concrete construction is a major contributor to greenhouse gas production, of which the major contributor is cement binding loading. Any optimization in concrete rheology and packing that can reduce cement loading and improve strength loading can also reduce currently required construction safety factors. The characterization approach here is also demonstrated for the impact of rock aggregate shape on concrete slump rheology and dry compressive strength.

  3. Synthesis and Characterization of Ag-Ag2O/TiO2@polypyrrole Heterojunction for Enhanced Photocatalytic Degradation of Methylene Blue

    Directory of Open Access Journals (Sweden)

    Rajeev Kumar

    2016-05-01

    Full Text Available Hybrid multi-functional nanomaterials comprising two or more disparate materials have become a powerful approach to obtain advanced materials for environmental remediation applications. In this work, an Ag-Ag2O/TiO2@polypyrrole (Ag/TiO2@PPy heterojunction has been synthesized by assembling a self-stabilized Ag-Ag2O (p type semiconductor (denoted as Ag and polypyrrole (π-conjugated polymer on the surface of rutile TiO2 (n type. Ag/TiO2@PPy was synthesized through simultaneous oxidation of pyrrole monomers and reduction of AgNO3 in an aqueous solution containing well-dispersed TiO2 particles. Thus synthesized Ag/TiO2@PPy was characterized using X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS, field emission scanning electron microscopy (FE-SEM, transmission electron microscopy (TEM, and UV-Vis diffuse reflectance spectroscopy (UV-vis DSR. The photocatalytic activity of synthesized heterojunction was investigated for the decomposition of methylene blue (MB dye under UV and visible light irradiation. The results revealed that π-conjugated p-n heterojunction formed in the case of Ag/TiO2@PPy significantly enhanced the photodecomposition of MB compared to the p-n type Ag/TiO2 and TiO2@PPy (n-π heterojunctions. A synergistic effect between Ag-Ag2O and PPy leads to higher photostability and a better electron/hole separation leads to an enhanced photocatalytic activity of Ag/TiO2@PPy under both UV and visible light irradiations.

  4. Direct Characterization of Kerogen By X-Ray And Solid-State **13C Nuclear Magnetic Resonance Methods

    Energy Technology Data Exchange (ETDEWEB)

    Keleman, S.R.; Afeworki, M.; Gorbaty, M.L.; Sansone, M.; Kwiatek, P.J.; Walters, C.C.; Freund, H.; Siskin, M.; Bence, A.E.; Curry, D.J.; Solum, M.; Pugmire, R.J.; Vandenbroucke, M.; Leblond, M.; Behar, F.

    2007-07-09

    and S-XANES results indicate that the relative level of aromatic sulfur increases with an increasing amount of aromatic carbon for all kerogens. XPS show that the majority of nitrogen exists as pyrrolic forms in comparable relative abundances in all kerogens studied. The direct characterization results using X-ray and NMR methods for nitrogen, sulfur, oxygen, and carbon chemical structures provide a basis for developing both specific and general average chemical structural models for different organic matter type kerogens.

  5. Direct Characterization of Kerogen by X-ray and Solid-State [superscript 13]C Nuclear Magnetic Resonance Methods

    Energy Technology Data Exchange (ETDEWEB)

    Kelemen, S. R.; Afeworki, M.; Gorbaty, M.L.; Sansone, M.; Kwiatek, P.J.; Walters, C.C.; Freund, H.; Siskin, M.; Bence, A.E.; Curry, D.J.; Solum, M.; Pugmire, R.J.; Vandenbroucke, M.; Leblond, M.; Behar, F. (ExxonMobil); (ExxonMobil); (IFP); (Utah)

    2008-06-12

    kerogens. XPS and S-XANES results indicate that the relative level of aromatic sulfur increases with an increasing amount of aromatic carbon for all kerogens. XPS show that the majority of nitrogen exists as pyrrolic forms in comparable relative abundances in all kerogens studied. The direct characterization results using X-ray and NMR methods for nitrogen, sulfur, oxygen, and carbon chemical structures provide a basis for developing both specific and general average chemical structural models for different organic matter type kerogens.

  6. Gloss Characterization: a Cyclic Approach

    OpenAIRE

    Viénot, Françoise

    2012-01-01

    In this paper, an approach to gloss characterization is described. We examine how information is transferred from the physical domain to the visual domain and how material properties are inferred from a cognitive interpretation, completing the characterization cycle.

  7. CHARACTERIZATION OF SOLID CONES

    Institute of Scientific and Technical Information of China (English)

    Qiu Jinghui

    2008-01-01

    The author gives a dual characterization of solid cones in locally convex spaces.From this the author obtains some criteria for judging convex cones to be solid in various inds of locally convex spaces. Using a general expression of the interior of a solid cone,the author obtains a number of necessary and sufficient conditions for convex cones to be solid in the framework of Banach spaces. In particular, the author gives a dual relationship between solid cones and generalized sharp cones. The related known results are improved and extended.

  8. Characterization of concurrent processing

    Science.gov (United States)

    Utku, S.; Melosh, R.; Salama, M.

    1985-01-01

    Computer architectures designed for concurrent processing are characterized by the number of processing elements, ensemble speed, random access memory, input/output routes, and modes of operation. The important attributes of processing tasks are then identified, and some processing stratagems are examined. It is shown that the greater the complexity of a given task, the wider the range of possible stratagems which can accomplish the task. For relatively simple tasks, the optimum stratagem can be found by analytical reasoning. For more complex tasks, however, optimum scheduling techniques may have to be employed for the assignment of segments of the task to the available processing elements.

  9. Spectroscopic Characterization of Metallofullerenes

    Science.gov (United States)

    Bethune, D. S.; de Vries, M. S.; Macfarlane, R.; Wittman, G.; Grannan, S.; Birmingham, J.; Richards, P.; Stevenson, S.; Glass, T.; Burbank, P.; Sun, Z.; Dorn, H. C.

    1996-03-01

    Scandium and Erbium metallofullerenes have been isolated using HPLC techniques and characterized by NMR, optical and far IR spectroscopy. In particular, Sc NMR spectra of Sc_2@C_2n species for several n have been obtained, and far infrared spectra of both discandium and and dierbium metallofullerenes have been measured. These show structure in the 20-200 cm-2 where vibrations of the encapsulated metal atoms are expected. Fluorescence spectra from dierbium metallofullerenes in the 1.5 μm region have been obtained at He and room temperatures.

  10. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Electrical and Communications Engineering

    1998-10-01

    Photovoltaic research in the Electron Physics Laboratory started in 1993, when laboratory joined the national TEKES/NEMO 2 research program. Since the beginning of the project, characterization as well as experimentally orientated development of the fabrication process of the solar cells were carried out parallery. The process development research started by the initiatives of the Finnish industry. At the moment a large amount of the laboratory personnel works on solar cell research and the financing comes mainly from external projects. The funding for the research has come from TEKES, Ministry of Education, Finnish Academy, GETA graduate school, special equipment grants of the university, and from the laboratory

  11. Ultrasonic materials characterization

    Science.gov (United States)

    Smith, R. L.

    1987-02-01

    The National NDT Center at Harwell has been developing methods for the characterization of materials using ultrasonics. This paper reviews the progress made in applying ultrasonic attenuation measurements to the determination of such quantities as grain size and dislocation content. A method, ultrasonic attenuation spectral analysis, has been developed, which enables the contributions of scattering and absorption to the total attenuation to be separated. The theoretical advances that have been made are also described. Some of the practical applications of the technique are illustrated and future development discussed.

  12. Network Characterization Service (NCS)

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Guojun [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Yang, George [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Crowley, Brian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Agarwal, Deborah [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2001-06-06

    Distributed applications require information to effectively utilize the network. Some of the information they require is the current and maximum bandwidth, current and minimum latency, bottlenecks, burst frequency, and congestion extent. This type of information allows applications to determine parameters like optimal TCP buffer size. In this paper, we present a cooperative information-gathering tool called the network characterization service (NCS). NCS runs in user space and is used to acquire network information. Its protocol is designed for scalable and distributed deployment, similar to DNS. Its algorithms provide efficient, speedy and accurate detection of bottlenecks, especially dynamic bottlenecks. On current and future networks, dynamic bottlenecks do and will affect network performance dramatically.

  13. Battery Thermal Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Keyser, Matthew; Saxon, Aron; Powell, Mitchell; Shi, Ying

    2016-06-07

    This poster shows the progress in battery thermal characterization over the previous year. NREL collaborated with U.S. DRIVE and USABC battery developers to obtain thermal properties of their batteries, obtained heat capacity and heat generation of cells under various power profiles, obtained thermal images of the cells under various drive cycles, and used the measured results to validate thermal models. Thermal properties are used for the thermal analysis and design of improved battery thermal management systems to support achieve life and performance targets.

  14. FRACTURING FLUID CHARACTERIZATION FACILITY

    Energy Technology Data Exchange (ETDEWEB)

    Subhash Shah

    2000-08-01

    Hydraulic fracturing technology has been successfully applied for well stimulation of low and high permeability reservoirs for numerous years. Treatment optimization and improved economics have always been the key to the success and it is more so when the reservoirs under consideration are marginal. Fluids are widely used for the stimulation of wells. The Fracturing Fluid Characterization Facility (FFCF) has been established to provide the accurate prediction of the behavior of complex fracturing fluids under downhole conditions. The primary focus of the facility is to provide valuable insight into the various mechanisms that govern the flow of fracturing fluids and slurries through hydraulically created fractures. During the time between September 30, 1992, and March 31, 2000, the research efforts were devoted to the areas of fluid rheology, proppant transport, proppant flowback, dynamic fluid loss, perforation pressure losses, and frictional pressure losses. In this regard, a unique above-the-ground fracture simulator was designed and constructed at the FFCF, labeled ''The High Pressure Simulator'' (HPS). The FFCF is now available to industry for characterizing and understanding the behavior of complex fluid systems. To better reflect and encompass the broad spectrum of the petroleum industry, the FFCF now operates under a new name of ''The Well Construction Technology Center'' (WCTC). This report documents the summary of the activities performed during 1992-2000 at the FFCF.

  15. PAU camera: detectors characterization

    Science.gov (United States)

    Casas, Ricard; Ballester, Otger; Cardiel-Sas, Laia; Castilla, Javier; Jiménez, Jorge; Maiorino, Marino; Pío, Cristóbal; Sevilla, Ignacio; de Vicente, Juan

    2012-07-01

    The PAU Camera (PAUCam) [1,2] is a wide field camera that will be mounted at the corrected prime focus of the William Herschel Telescope (Observatorio del Roque de los Muchachos, Canary Islands, Spain) in the next months. The focal plane of PAUCam is composed by a mosaic of 18 CCD detectors of 2,048 x 4,176 pixels each one with a pixel size of 15 microns, manufactured by Hamamatsu Photonics K. K. This mosaic covers a field of view (FoV) of 60 arcmin (minutes of arc), 40 of them are unvignetted. The behaviour of these 18 devices, plus four spares, and their electronic response should be characterized and optimized for the use in PAUCam. This job is being carried out in the laboratories of the ICE/IFAE and the CIEMAT. The electronic optimization of the CCD detectors is being carried out by means of an OG (Output Gate) scan and maximizing it CTE (Charge Transfer Efficiency) while the read-out noise is minimized. The device characterization itself is obtained with different tests. The photon transfer curve (PTC) that allows to obtain the electronic gain, the linearity vs. light stimulus, the full-well capacity and the cosmetic defects. The read-out noise, the dark current, the stability vs. temperature and the light remanence.

  16. Mound facility physical characterization

    Energy Technology Data Exchange (ETDEWEB)

    Tonne, W.R.; Alexander, B.M.; Cage, M.R.; Hase, E.H.; Schmidt, M.J.; Schneider, J.E.; Slusher, W.; Todd, J.E.

    1993-12-01

    The purpose of this report is to provide a baseline physical characterization of Mound`s facilities as of September 1993. The baseline characterizations are to be used in the development of long-term future use strategy development for the Mound site. This document describes the current missions and alternative future use scenarios for each building. Current mission descriptions cover facility capabilities, physical resources required to support operations, current safety envelope and current status of facilities. Future use scenarios identify potential alternative future uses, facility modifications required for likely use, facility modifications of other uses, changes to safety envelope for the likely use, cleanup criteria for each future use scenario, and disposition of surplus equipment. This Introductory Chapter includes an Executive Summary that contains narrative on the Functional Unit Material Condition, Current Facility Status, Listing of Buildings, Space Plans, Summary of Maintenance Program and Repair Backlog, Environmental Restoration, and Decontamination and Decommissioning Programs. Under Section B, Site Description, is a brief listing of the Site PS Development, as well as Current Utility Sources. Section C contains Site Assumptions. A Maintenance Program Overview, as well as Current Deficiencies, is contained within the Maintenance Program Chapter.

  17. Characterization of Paper Heterogeneity

    Science.gov (United States)

    Considine, John M.

    Paper and paperboard are the most widely-used green materials in the world because they are renewable, recyclable, reusable, and compostable. Continued and expanded use of these materials and their potential use in new products requires a comprehensive understanding of the variability of their mechanical properties. This work develops new methods to characterize the mechanical properties of heterogeneous materials through a combination of techniques in experimental mechanics, materials science and numerical analysis. Current methods to analyze heterogeneous materials focus on crystalline materials or polymer-crystalline composites, where material boundaries are usually distinct. This work creates a methodology to analyze small, continuously-varying stiffness gradients in 100% polymer systems and is especially relevant to paper materials where factors influencing heterogeneity include local mass, fiber orientation, individual pulp fiber properties, local density, and drying restraint. A unique approach was used to understand the effect of heterogeneity on paper tensile strength. Additional variation was intentionally introduced, in the form of different size holes, and their effect on strength was measured. By modifying two strength criteria, an estimate of strength in the absence of heterogeneity was determined. In order to characterize stiffness heterogeneity, a novel load fixture was developed to excite full-field normal and shear strains for anisotropic stiffness determination. Surface strains were measured with digital image correlation and were analyzed with the VFM (Virtual Fields Method). This approach led to VFM-identified stiffnesses that were similar to values determined by conventional tests. The load fixture and VFM analyses were used to measure local stiffness and local stiffness variation on heterogeneous anisotropic materials. The approach was validated on simulated heterogeneous materials and was applied experimentally to three different paperboards

  18. Land Cover Characterization Program

    Science.gov (United States)

    ,

    1997-01-01

    The U.S. Geological Survey (USGS) has a long heritage of leadership and innovation in land use and land cover mapping. The USGS Anderson system defined the principles for land use and land cover mapping that have been the model both nationally and internationally for more than 20 years. The Land Cover Characterization Program (LCCP) is founded on the premise that the Nation's needs for land cover and land use data are diverse and increasingly sophisticated. The range of projects, programs, and organizations that use land cover data to meet their planning, management, development, and assessment objectives has expanded significantly. The reasons for this are numerous, and include the improved capabilities provided by geographic information systems, better and more data-intensive analytic models, and increasing requirements for improved information for decision making. The overall goals of the LCCP are to:

  19. ANALYTICAL CHARACTERIZATION OF PRECIPITATIONS

    Directory of Open Access Journals (Sweden)

    Danut Tiberiu Epure

    2011-02-01

    Full Text Available The properties of precipitation are mainly determined by solid, liquid and gaseous substances that exist in suspended or dissolved form. These substances come from many complex interactions between the atmosphere – hydrosphere – lithosphere – biota. The analytical characterization of precipitation has been based on the analysis of several chemical parameters: pH, conductivity, chloride, fluoride and ammonium ions, total hardness, alkalinity, H2S and sulphides, COD (Mn, nitrites, phosphorous, metallic ions (total iron, copper and chromium. In this purpose were collected rainwater, ice and snow from different areas (cities Năvodari, Constanţa, Buzău and Mihail Kogălniceanu during November 2007 till February 2008. This study shows that chemical characteristics of the analyzed water samples vary from one region to another depending on the mineralogical composition of zones crossed, the contact time, temperature, weather conditions, the sampling period (day or night and the nature of sample (rain, snow, ice.

  20. EIGER characterization results

    Energy Technology Data Exchange (ETDEWEB)

    Dinapoli, Roberto, E-mail: roberto.dinapoli@psi.ch [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Bergamaschi, Anna; Greiffenberg, Dominic; Henrich, Beat; Horisberger, Roland; Johnson, Ian; Mozzanica, Aldo [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Radicci, Valeria [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); ESRF, 6 Rue Horowitz, 38043 Grenoble (France); Schmitt, Bernd; Shi, Xintian [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); Tinti, Gemma [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland); ESRF, 6 Rue Horowitz, 38043 Grenoble (France)

    2013-12-11

    Characterization and performance measurements have been done on several EIGER detector systems, produced with chips coming from two different lots, both with a lab X-ray source and at the Swiss Light Source (SLS). Results on the detector calibration, electronic noise, threshold dispersion, minimum achievable energy threshold, maximum detectable incoming photon flux and maximum frame rate are presented. An EIGER module is constructed from a ∼4×8cm{sup 2} monolithic silicon sensor bump-bonded to 2 ×4 readout chips and contains 0.5 Mpixel. The first EIGER 500 K systems have been produced and images taken with these detectors are shown. Modules can be tiled together to form large area detectors; both a 9 Mpixel and a 16 Mpixel systems are at present under development for the coherent small angle X-ray scattering and protein crystallography beamlines of the SLS.

  1. EIGER characterization results

    Science.gov (United States)

    Dinapoli, Roberto; Bergamaschi, Anna; Greiffenberg, Dominic; Henrich, Beat; Horisberger, Roland; Johnson, Ian; Mozzanica, Aldo; Radicci, Valeria; Schmitt, Bernd; Shi, Xintian; Tinti, Gemma

    2013-12-01

    Characterization and performance measurements have been done on several EIGER detector systems, produced with chips coming from two different lots, both with a lab X-ray source and at the Swiss Light Source (SLS). Results on the detector calibration, electronic noise, threshold dispersion, minimum achievable energy threshold, maximum detectable incoming photon flux and maximum frame rate are presented. An EIGER module is constructed from a ∼4×8 cm2 monolithic silicon sensor bump-bonded to 2 ×4 readout chips and contains 0.5 Mpixel. The first EIGER 500 K systems have been produced and images taken with these detectors are shown. Modules can be tiled together to form large area detectors; both a 9 Mpixel and a 16 Mpixel systems are at present under development for the coherent small angle X-ray scattering and protein crystallography beamlines of the SLS.

  2. Radiation characterization summary :

    Energy Technology Data Exchange (ETDEWEB)

    Parma, Edward J.,; Quirk, Thomas J.; Lippert, Lance L.; Griffin, Patrick J; Naranjo, Gerald E.; Luker, Spencer Michael

    2013-04-01

    This document presents the facility-recommended characterization of the neutron, prompt gamma-ray, and delayed gamma-ray radiation fields in the Annular Core Research Reactor (ACRR) for the 44-inch-long lead-boron bucket in the central cavity on the 32-inch pedestal at the core centerline. The designation for this environment is ACRR-LB44-CC-32-cl. The neutron, prompt gamma-ray, and delayed gamma-ray energy spectra are presented as well as radial and axial neutron and gamma-ray flux profiles within the experiment area of the bucket. Recommended constants are given to facilitate the conversion of various dosimetry readings into radiation metrics desired by experimenters. Representative pulse and steady-state operations are presented with conversion examples.

  3. System Performance Characterization

    Energy Technology Data Exchange (ETDEWEB)

    van Dam, M A

    2004-05-26

    Characterizing an adaptive optics (AO) system refers to understanding its performance and limitations. The goal of an AO system is to correct wavefront aberrations. The uncorrected aberrations, called the residual errors and referred to in what follows simply as the errors, degrade the image quality in the science camera. Understanding the source of these errors is a great aid in designing an AO system and optimizing its performance. This chapter explains how to estimate the wavefront error terms and the relationship between the wavefront error and the degradation of the image. The analysis deals with the particular case of a HartmannShack wavefront sensor (WFS) and a continuous deformable mirror (DM), although the principles involved can be applied to any AO system.

  4. CHARACTERIZATION OF DAMAGED MATERIALS

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, P C; Dehaven, M; McClelland, M; Chidester, S; Maienschein, J L

    2006-06-23

    Thermal damage experiments were conducted on LX-04, LX-10, and LX-17 at high temperatures. Both pristine and damaged samples were characterized for their material properties. A pycnometer was used to determine sample true density and porosity. Gas permeability was measured in a newly procured system (diffusion permeameter). Burn rate was measured in the LLNL strand burner. Weight losses upon thermal exposure were insignificant. Damaged pressed parts expanded, resulting in a reduction of bulk density by up to 10%. Both gas permeabilities and burn rates of the damaged samples increased by several orders of magnitude due to higher porosity and lower density. Moduli of the damaged materials decreased significantly, an indication that the materials became weaker mechanically. Damaged materials were more sensitive to shock initiation at high temperatures. No significant sensitization was observed when the damaged samples were tested at room temperature.

  5. Spectroradiometry for LED characterization

    DEFF Research Database (Denmark)

    Dam-Hansen, Carsten

    Radiospectroscopy is the absolute measurement of electromagnetic radiation within a specific wavelength range. For characterization of LED components, light sources and lamps we are interested in absolute measurement of the spectral power distribution, SPD, in the visible and near infrared region....... Using integrating spheres for light collection setups for absolute total spectral flux is realized at the LED Light Lab at DTU Fotonik, Risø Campus. From these, both total radiant and luminous flux is determined and through electrical power measurement also the efficiency is determined. From the SPD...... colorimetric quantities like color coordinates, color temperature and color rendering indices are calculated. The facilities and special issues concerning LED measurements compared to traditional light sources are explained and examples from the “LED lighting quality program”, a project supported by the Danish...

  6. Photoelectronic characterization of heterointerfaces.

    Energy Technology Data Exchange (ETDEWEB)

    Brumbach, Michael Todd

    2012-02-01

    In many devices such as solar cells, light emitting diodes, transistors, etc., the performance relies on the electronic structure at interfaces between materials within the device. The objective of this work was to perform robust characterization of hybrid (organic/inorganic) interfaces by tailoring the interfacial region for photoelectron spectroscopy. Self-assembled monolayers (SAM) were utilized to induce dipoles of various magnitudes at the interface. Additionally, SAMs of molecules with varying dipolar characteristics were mixed into spatially organized structures to systematically vary the apparent work function. Polymer thin films were characterized by depositing films of varying thicknesses on numerous substrates with and without interfacial modifications. Hard X-ray photoelectron spectroscopy (HAXPES) was performed to evaluate a buried interface between indium tin oxide (ITO), treated under various conditions, and poly(3-hexylthiophene) (P3HT). Conducting polymer films were found to be sufficiently conducting such that no significant charge redistribution in the polymer films was observed. Consequently, a further departure from uniform substrates was taken whereby electrically disconnected regions of the substrate presented ideally insulating interfacial contacts. In order to accomplish this novel strategy, interdigitated electrodes were used as the substrate. Conducting fingers of one half of the electrodes were electrically grounded while the other set of electrodes were electronically floating. This allowed for the evaluation of substrate charging on photoelectron spectra (SCOPES) in the presence of overlying semiconducting thin films. Such an experiment has never before been reported. This concept was developed out of the previous experiments on interfacial modification and thin film depositions and presents new opportunities for understanding chemical and electronic changes in a multitude of materials and interfaces.

  7. Mixed waste characterization reference document

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    Waste characterization and monitoring are major activities in the management of waste from generation through storage and treatment to disposal. Adequate waste characterization is necessary to ensure safe storage, selection of appropriate and effective treatment, and adherence to disposal standards. For some wastes characterization objectives can be difficult and costly to achieve. The purpose of this document is to evaluate costs of characterizing one such waste type, mixed (hazardous and radioactive) waste. For the purpose of this document, waste characterization includes treatment system monitoring, where monitoring is a supplement or substitute for waste characterization. This document establishes a cost baseline for mixed waste characterization and treatment system monitoring requirements from which to evaluate alternatives. The cost baseline established as part of this work includes costs for a thermal treatment technology (i.e., a rotary kiln incinerator), a nonthermal treatment process (i.e., waste sorting, macronencapsulation, and catalytic wet oxidation), and no treatment (i.e., disposal of waste at the Waste Isolation Pilot Plant (WIPP)). The analysis of improvement over the baseline includes assessment of promising areas for technology development in front-end waste characterization, process equipment, off gas controls, and monitoring. Based on this assessment, an ideal characterization and monitoring configuration is described that minimizes costs and optimizes resources required for waste characterization.

  8. Mixed waste characterization reference document

    International Nuclear Information System (INIS)

    Waste characterization and monitoring are major activities in the management of waste from generation through storage and treatment to disposal. Adequate waste characterization is necessary to ensure safe storage, selection of appropriate and effective treatment, and adherence to disposal standards. For some wastes characterization objectives can be difficult and costly to achieve. The purpose of this document is to evaluate costs of characterizing one such waste type, mixed (hazardous and radioactive) waste. For the purpose of this document, waste characterization includes treatment system monitoring, where monitoring is a supplement or substitute for waste characterization. This document establishes a cost baseline for mixed waste characterization and treatment system monitoring requirements from which to evaluate alternatives. The cost baseline established as part of this work includes costs for a thermal treatment technology (i.e., a rotary kiln incinerator), a nonthermal treatment process (i.e., waste sorting, macronencapsulation, and catalytic wet oxidation), and no treatment (i.e., disposal of waste at the Waste Isolation Pilot Plant (WIPP)). The analysis of improvement over the baseline includes assessment of promising areas for technology development in front-end waste characterization, process equipment, off gas controls, and monitoring. Based on this assessment, an ideal characterization and monitoring configuration is described that minimizes costs and optimizes resources required for waste characterization

  9. Synthesis by plasma and characterization of compounds derived from polyacetylene; Sintesis por plasma y caracterizacion de compuestos derivados del poliacetileno

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez O, M

    2004-07-01

    This work presents a study on, the synthesis by plasma and the characterization of an aliphatic conjugated polymer, polyacetylene-chlorinated (Pac), and two aromatic polymers, Poly pyrrole (P Py-Cl) and Poly thiophene (Pth-Cl) synthesized with chlorine and the electrical conductivity. The last two polymers were synthesized to compare the chlorine-polymer interaction in aliphatic and aromatic polymers synthesized by plasma and their repercussion on the electrical transport of charges in the material. The structure and morphology of the polymers were studied using scanning electron microscopy (Sem), energy dispersive spectroscopy (EDS), infrared spectroscopy (Ft-IR), conductivity analysis and X-Ray photon spectroscopy (XPS). The results showed that Pac is soluble in acetone and other organic solvents, which indicates a low proportion of crosslinking in the polymers. This point is important because the crosslinking reduces the electrical conductivity in the material. The Pac conductivity is in the range of 1 x 10{sup -12} to 6 x 10{sup -4} S/cm in the internal of 35- 90% of relative humidity. A possible mechanism for the transport of electrical charges in Pac is by means of the double and simple conjugated bonds in the polymers. Pth-Cl and P Py-Cl present electric conductivity in the interval of 9 x 10{sup -5} to 1 x 10{sup -2} S/cm and show a great dependence on the relative humidity. The chlorine addition in these polymers was through simultaneous polymerization with chloroform. This last compound can decompose if the energy of the plasma is relatively high, and the fragments can link to the polymer in a hybrid process of copolymerization. An important point of this work is that the polymer is soluble, a difference of the obtained via plasma as the poli aniline, P Py-CI and Pth-Cl both studied in this work. If took in account that the Pac is single the monomer and that P Py-Cl and Pth-CI is affected by the chlorine that modifies the conductivity of the material

  10. Nanometer Characterization/Manipulation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — FUNCTION: Characterizes the nanometer scale of biological, chemical, physical, electronic, and mechanical properties of surfaces and thin films using scanning probe...

  11. Characterizing Nanoscale Transient Communication.

    Science.gov (United States)

    Chen, Yifan; Anwar, Putri Santi; Huang, Limin; Asvial, Muhamad

    2016-04-01

    We consider the novel paradigm of nanoscale transient communication (NTC), where certain components of the small-scale communication link are physically transient. As such, the transmitter and the receiver may change their properties over a prescribed lifespan due to their time-varying structures. The NTC systems may find important applications in the biomedical, environmental, and military fields, where system degradability allows for benign integration into life and environment. In this paper, we analyze the NTC systems from the channel-modeling and capacity-analysis perspectives and focus on the stochastically meaningful slow transience scenario, where the coherence time of degeneration Td is much longer than the coding delay Tc. We first develop novel and parsimonious models to characterize the NTC channels, where three types of physical layers are considered: electromagnetism-based terahertz (THz) communication, diffusion-based molecular communication (DMC), and nanobots-assisted touchable communication (TouchCom). We then revisit the classical performance measure of ϵ-outage channel capacity and take a fresh look at its formulations in the NTC context. Next, we present the notion of capacity degeneration profile (CDP), which describes the reduction of channel capacity with respect to the degeneration time. Finally, we provide numerical examples to demonstrate the features of CDP. To the best of our knowledge, the current work represents a first attempt to systematically evaluate the quality of nanoscale communication systems deteriorating with time.

  12. Plant Phenotype Characterization System

    Energy Technology Data Exchange (ETDEWEB)

    Daniel W McDonald; Ronald B Michaels

    2005-09-09

    This report is the final scientific report for the DOE Inventions and Innovations Project: Plant Phenotype Characterization System, DE-FG36-04GO14334. The period of performance was September 30, 2004 through July 15, 2005. The project objective is to demonstrate the viability of a new scientific instrument concept for the study of plant root systems. The root systems of plants are thought to be important in plant yield and thus important to DOE goals in renewable energy sources. The scientific study and understanding of plant root systems is hampered by the difficulty in observing root activity and the inadequacy of existing root study instrumentation options. We have demonstrated a high throughput, non-invasive, high resolution technique for visualizing plant root systems in-situ. Our approach is based upon low-energy x-ray radiography and the use of containers and substrates (artificial soil) which are virtually transparent to x-rays. The system allows us to germinate and grow plant specimens in our containers and substrates and to generate x-ray images of the developing root system over time. The same plant can be imaged at different times in its development. The system can be used for root studies in plant physiology, plant morphology, plant breeding, plant functional genomics and plant genotype screening.

  13. Characterizing protein crystal nucleation

    Science.gov (United States)

    Akella, Sathish V.

    We developed an experimental microfluidic based technique to measure the nucleation rates and successfully applied the technique to measure nucleation rates of lysozyme crystals. The technique involves counting the number of samples which do not have crystals as a function of time. Under the assumption that nucleation is a Poisson process, the fraction of samples with no crystals decays exponentially with the decay constant proportional to nucleation rate and volume of the sample. Since nucleation is a random and rare event, one needs to perform measurements on large number of samples to obtain good statistics. Microfluidics offers the solution of producing large number of samples at minimal material consumption. Hence, we developed a microfluidic method and measured nucleation rates of lysozyme crystals in supersaturated protein drops, each with volume of ˜ 1 nL. Classical Nucleation Theory (CNT) describes the kinetics of nucleation and predicts the functional form of nucleation rate in terms of the thermodynamic quantities involved, such as supersaturation, temperature, etc. We analyzed the measured nucleation rates in the context of CNT and obtained the activation energy and the kinetic pre-factor characterizing the nucleation process. One conclusion is that heterogeneous nucleation dominates crystallization. We report preliminary studies on selective enhancement of nucleation in one of the crystal polymorprhs of lysozyme (spherulite) using amorphous mesoporous bioactive gel-glass te{naomi06, naomi08}, CaO.P 2O5.SiO2 (known as bio-glass) with 2-10 nm pore-size diameter distribution. The pores act as heterogeneous nucleation centers and claimed to enhance the nucleation rates by molecular confinement. The measured kinetic profiles of crystal fraction of spherulites indicate that the crystallization of spherulites may be proceeding via secondary nucleation pathways.

  14. Characterization Of Robot Work Cell

    Science.gov (United States)

    Anderson, Ronald R.; Paternoster, Vincent Y.; Guthmiller, Wayne A.

    1990-01-01

    Iterative process of measurement and computation used to characterize work cell of robot, increasing accuracy of mathematical model of work cell. Characterization needed because model used in off-line programming (OLP) to compute paths to control motion of robot. Increases accuracies of model and paths.

  15. Tank characterization technical sampling basis

    Energy Technology Data Exchange (ETDEWEB)

    Brown, T.M.

    1998-04-28

    Tank Characterization Technical Sampling Basis (this document) is the first step of an in place working process to plan characterization activities in an optimal manner. This document will be used to develop the revision of the Waste Information Requirements Document (WIRD) (Winkelman et al. 1997) and ultimately, to create sampling schedules. The revised WIRD will define all Characterization Project activities over the course of subsequent fiscal years 1999 through 2002. This document establishes priorities for sampling and characterization activities conducted under the Tank Waste Remediation System (TWRS) Tank Waste Characterization Project. The Tank Waste Characterization Project is designed to provide all TWRS programs with information describing the physical, chemical, and radiological properties of the contents of waste storage tanks at the Hanford Site. These tanks contain radioactive waste generated from the production of nuclear weapons materials at the Hanford Site. The waste composition varies from tank to tank because of the large number of chemical processes that were used when producing nuclear weapons materials over the years and because the wastes were mixed during efforts to better use tank storage space. The Tank Waste Characterization Project mission is to provide information and waste sample material necessary for TWRS to define and maintain safe interim storage and to process waste fractions into stable forms for ultimate disposal. This document integrates the information needed to address safety issues, regulatory requirements, and retrieval, treatment, and immobilization requirements. Characterization sampling to support tank farm operational needs is also discussed.

  16. Spectral characterization of abstract functions

    International Nuclear Information System (INIS)

    Let G be locally compact abelian group and GAMMA its dual group. Let X be locally convex complete space and X* its dual space. In this paper we give spectral characterization of bounded uniformly continuous functions from G to X. Also, we give applications to the characterization of solutions of functional differential equations. (author)

  17. Particle characterization for geothermal operations

    Energy Technology Data Exchange (ETDEWEB)

    Vetter, O.J.; Kandarpa, V.

    1981-01-06

    A detailed summary of an ongoing evaluation of existing particle measuring methodology with emphasis on (a) adapting of existing methods in geothermal operations and (b) further development of existing instrumentation for field use is presented. The various instruments and methods used and/or suggested for particle characterization are described in detail. Theoretical and practical aspects of particle characterizations are outlined. A plan for further laboratory and field experiments is outlined. The instrumentations to be selected after some additional lab and field tests will be used in the studies on (a) formation damage through particle invasion and (b) characterizing and monitoring of particle suspensions in geothermal operations.

  18. Uruguayan tallow characterization

    Directory of Open Access Journals (Sweden)

    Cecilia Rodríguez

    2011-04-01

    Full Text Available Eatable tallow is the product  obtained fusing oily, from clean and  healthy tissues (included the fats of clippings, and from muscles or bones adherents of bovine animals (Bos tsurus,  lambs (Ovis aries in good conditions of health in the moment of its sacrifice and whose has been treated and therefore are considered suitable for the human consumption.To obtain fat from the raw, this material must surrender to a previous treatment that breaks the adipose cells, by  mechanical destruction, boiling or by treatment with alcáli. The easiest  way  consists of the mechanical disintegration (breakup under heat, using steam in direct or indirect form. This product can be obtained by one of the following : discontinuous merger, humid constant merger and  continues merger at low temperature. At present is used in the  cosmetic industry (production of soaps, for nutrition (raw material for margarine, ranching (for the manufacture of food concentrated for animals, for the self propelling industry (raw material for the production of biodiesel. The major purpose of this work is the tallow characterization from the determination of the following parameters :Moisture and Volatile Matter (g/100g of sample, Melting Point (1C, Free Acidity (g. Oleic acid /100g of sample, Colour (yellow and red and Insoluble Matter (g/100g.de shows of 15 samples of animal tallow from Uruguay, in order to provide useful information for the selection of the material. The Norm used as reference was the AOCS (American Oil Chemistry Society. With the obtained information it has been realized a statistical exploratory analysis. The preliminary results, due to the high variability of the studied factors, do not allow to establish with the current number of samples a  model who explains the above mentioned variability, neither at first, to reduce the quantity of factors to consider; in effect, the regression of the moisture against the rest of the factors determined the

  19. 324 Building Baseline Radiological Characterization

    Energy Technology Data Exchange (ETDEWEB)

    R.J. Reeder, J.C. Cooper

    2010-06-24

    This report documents the analysis of radiological data collected as part of the characterization study performed in 1998. The study was performed to create a baseline of the radiological conditions in the 324 Building.

  20. Waste Characterization: Approaches and Methods

    DEFF Research Database (Denmark)

    Lagerkvist, A.; Ecke, H.; Christensen, Thomas Højlund

    2011-01-01

    Characterization of solid waste is usually a difficult task because of the heterogeneity of the waste and its spatial as well as temporal variations. This makes waste characterization costly if good and reliable data with reasonable uncertainty is to be obtained. Therefore, a waste characterization...... is often narrowly defined to meet specific needs for information. This may however limit the general usefulness of the information gained, for example, if the specific purpose limited the characterization to a subset of variables. In general, data available in the solid waste area are limited and often...... related to individual treatment processes and waste products are dealt with in the following chapters: Characteristic data on residential waste (Chapter 2.2), commercial and institutional waste (Chapter 2.3), industrial waste (Chapter 2.4) and construction and demolition waste (Chapter 2...

  1. CCD characterization and measurements automation

    International Nuclear Information System (INIS)

    Modern mosaic cameras have grown both in size and in number of sensors. The required volume of sensor testing and characterization has grown accordingly. For camera projects as large as the LSST, test automation becomes a necessity. A CCD testing and characterization laboratory was built and is in operation for the LSST project. Characterization of LSST study contract sensors has been performed. The characterization process and its automation are discussed, and results are presented. Our system automatically acquires images, populates a database with metadata information, and runs express analysis. This approach is illustrated on 55Fe data analysis. 55Fe data are used to measure gain, charge transfer efficiency and charge diffusion. Examples of express analysis results are presented and discussed.

  2. Characterization of polyacrylonitrile ultrafiltration membranes

    NARCIS (Netherlands)

    Germic, J.; Ebert, K.; Bouma, R.H.B.; Borneman, Z.; Mulder, M.H.V.; Strathmann, H.

    1997-01-01

    Various methods have been used to characterize ultrafiltration membranes, such as gas flux measurements, (field emission) scanning electron microscopy, permporometry and liquid-liquid displacement. Significant differences in the pore size distributions determined from permporometry and liquid-liquid

  3. Characterizing Financial and Statistical Literacy

    DEFF Research Database (Denmark)

    Di Girolamo, Amalia; Harrison, Glenn W.; Lau, Morten;

    We characterize the literacy of an individual in a domain by their elicited subjective belief distribution over the possible responses to a question posed in that domain. We consider literacy across several financial, economic and statistical domains. We find considerable demographic heterogeneit...... approach to characterize financial capability, the consequences of non-literacy, social literacy, and the information content of hypothetical survey measures of literacy.......We characterize the literacy of an individual in a domain by their elicited subjective belief distribution over the possible responses to a question posed in that domain. We consider literacy across several financial, economic and statistical domains. We find considerable demographic heterogeneity...... in the degree of literacy. We also characterize the degree of consistency within a sample about their knowledge, even when that knowledge is imperfect. We show how uncertainty aversion might be a normatively attractive behavior for individuals who have imperfect literacy. Finally, we discuss extensions of our...

  4. Hanford site waste tank characterization

    International Nuclear Information System (INIS)

    This paper describes the on-going work in the characterization of the Hanford-Site high-level waste tanks. The waste in these tanks was produced as part of the nuclear weapons materials processing mission that occupied the Hanford Site for the first 40 years of its existence. Detailed and defensible characterization of the tank wastes is required to guide retrieval, pretreatment, and disposal technology development, to address waste stability and reactivity concerns, and to satisfy the compliance criteria for the various regulatory agencies overseeing activities at the Hanford Site. The resulting Tank Characterization Reports fulfill these needs, as well as satisfy the tank waste characterization milestones in the Hanford Federal Facility Agreement and Consent Order

  5. Colorimetric characterization of LED luminaires

    Science.gov (United States)

    Costa, C. L. M.; Vieira, R. R.; Pereira, R. C.; Silva, P. V. M.; Oliveira, I. A. A.; Sardinha, A. S.; Viana, D. D.; Barbosa, A. H.; Souza, L. P.; Alvarenga, A. D.

    2015-01-01

    The Optical Metrology Division of Inmetro - National Institute of Metrology, Quality and Technology has recently started the colorimetric characterization of lamps by implementing Correlated Color Temperature (CCT) and Color Rendering Index (CRI) measurements of incandescent lamps, followed by the CFL, and LED lamps and luminaires. Here we present the results for the verification of the color characterization of samples of SSL luminaires for public as well as indoor illumination that are sold in Brazil.

  6. Microsystems for biological cell characterization

    OpenAIRE

    Rissanen, Anna

    2012-01-01

    This thesis describes three techniques for the characterization of living cells using micro-electro-mechanical systems (MEMS) based devices. The study of cellular function and structure is essential for bioprocess control, disease diagnosis, patient treatment and drug discovery. Microsystem technology enables characterization of very small samples, minimal use of expensive reagents, testing of multiple samples in parallel, and point-of-care testing, all of which increase throughput and reduce...

  7. Colorimetric characterization of LED luminaires

    International Nuclear Information System (INIS)

    The Optical Metrology Division of Inmetro – National Institute of Metrology, Quality and Technology has recently started the colorimetric characterization of lamps by implementing Correlated Color Temperature (CCT) and Color Rendering Index (CRI) measurements of incandescent lamps, followed by the CFL, and LED lamps and luminaires. Here we present the results for the verification of the color characterization of samples of SSL luminaires for public as well as indoor illumination that are sold in Brazil

  8. Characterization of radioactive hazardous waste

    International Nuclear Information System (INIS)

    The characterization of radioactive hazardous waste, also known as transuranic 'mixed waste' has to be completed before it can be classified for proper treatment (incinerator, mechanical compaction or thermal treatment), packing, and transport. The characterization of the TRU mixed waste is not only complex process but rather an expensive undertaking. The process knowledge is the basic foundation of characterization. It is the documented knowledge of processes and materials that generated the waste. The transuranic waste Quality Assurance Program Plan (QAPP) defines the Data Quality Objectives (DQO's) and provides the scope of analytical parameters and methods required to accurately characterize the radioactive mixed waste. Based on the historical data and process knowledge a sampling and analysis plan can be developed to characterize the radioactive hazardous waste. Based on the characterization, an assessment of the regulatory status can be made before the waste could be accepted for disposal at the WIPP facility. The Waste Acceptance Criteria (WAC) developed by WIPP defines the parameters for receiving and final disposal of the TRU waste. The sets of criteria, such as: heat generated, fissile gram equivalent (FGE), plutonium-equivalent (PE) curies, and specifications of a dose rate have to be met before the waste is accepted for deep geological disposal. The characterization of radioactive waste becomes even more complex due to the presence of iron base metals/alloys, aluminum base metals/alloys, organic, chelating agents that are mixed with plastic, rubber, cellulose, soils and cement. Some of the modern characterization technologies that are under development and currently used for TRU mixed wastes are: nondestructive examination, nondestructive assay, headspace gas analysis, and drum coring for Resources Conservation Recovery Act (RCRA) sampling. (author)

  9. Vortex Characterization for Engineering Applications

    Energy Technology Data Exchange (ETDEWEB)

    Jankun-Kelly, M; Thompson, D S; Jiang, M; Shannahan, B; Machiraju, R

    2008-01-30

    Realistic engineering simulation data often have features that are not optimally resolved due to practical limitations on mesh resolution. To be useful to application engineers, vortex characterization techniques must be sufficiently robust to handle realistic data with complex vortex topologies. In this paper, we present enhancements to the vortex topology identification component of an existing vortex characterization algorithm. The modified techniques are demonstrated by application to three realistic data sets that illustrate the strengths and weaknesses of our approach.

  10. NMR characterization of thin films

    Science.gov (United States)

    Gerald, II, Rex E.; Klingler, Robert J.; Rathke, Jerome W.; Diaz, Rocio; Vukovic, Lela

    2008-11-25

    A method, apparatus, and system for characterizing thin film materials. The method, apparatus, and system includes a container for receiving a starting material, applying a gravitational force, a magnetic force, and an electric force or combinations thereof to at least the starting material, forming a thin film material, sensing an NMR signal from the thin film material and analyzing the NMR signal to characterize the thin film of material.

  11. A NEW METHOD ON THE CHEMICAL SYNTHESIS OF DOPED POLYPYRROLE INITIATED BY CuCl2-C2H5OH SYSTEM

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jie; SHE Yongbo; LU Bin; ZHOU Yuliang; FU Kejian

    1993-01-01

    Our objectives were to develop a new chemical method for the polymerization of pyrrole. CuCl2 dissolved in C2H5OH solvent is primarily used for the initiation polymerization of pyrrole. The polymers with different yield and conductivity were obtained by varing the initial concentration of Cu2+. The initial concentrations of Cu2+ varied from 1.2 × 10-4 mole to 6.48 ×10-3 mole Cu2+ with 2. 16 × 10-2mole pyrrole. The polypyrrole obtained was characterized with elemental analyzer, XPS, IR spectroscopy, Four-point probe and SEM.

  12. High Speed On-Wafer Characterization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — At the High Speed On-Wafer Characterization Laboratory, researchers characterize and model devices operating at terahertz (THz) and millimeter-wave frequencies. The...

  13. Characterization of nanometer tungsten powders

    Institute of Scientific and Technical Information of China (English)

    LI Huiqian; LIN Tao; SHAO Huiping; WU Chengyi; GUO Zhimeng; LUO Ji

    2008-01-01

    Three types of tungsten powders were prepared by hydrogen reduction of three precursor powders at low temperature,which were used as samples,and were then characterized by Brunauer-Emmer-Teller (BET) method,scanning electron microscopy (SEM),transmission electronic microscopy (TEM),small angle X-ray scattering (SAXS),and field-emission scanning electron microscopy (FESEM) respectively.The results showed that although BET and SEM could not characterize the particle size of nanometer powders,they were important means of assistance to exclude non-nanometer powders.TEM and FESEM could directly measure the particle size of nanometer powders,but this needs a lot of time,to count the average particle size and particle size distribution.SAXS could not describe the state of agglomeration.By the combination of FESEM and SAXS,the particle size,particle size distribution,and particle shape of nanorneter powders could be preciscly characterized.

  14. Image Analysis for Tongue Characterization

    Institute of Scientific and Technical Information of China (English)

    SHENLansun; WEIBaoguo; CAIYiheng; ZHANGXinfeng; WANGYanqing; CHENJing; KONGLingbiao

    2003-01-01

    Tongue diagnosis is one of the essential methods in traditional Chinese medical diagnosis. The ac-curacy of tongue diagnosis can be improved by tongue char-acterization. This paper investigates the use of image anal-ysis techniques for tongue characterization by evaluating visual features obtained from images. A tongue imaging and analysis instrument (TIAI) was developed to acquire digital color tongue images. Several novel approaches are presented for color calibration, tongue area segmentation,quantitative analysis and qualitative description for the colors of tongue and its coating, the thickness and moisture of coating and quantification of the cracks of the toilgue.The overall accuracy of the automatic analysis of the colors of tongue and the thickness of tongue coating exceeds 85%.This work shows the promising future of tongue character-ization.

  15. Characterizing the human hematopoietic CDome

    DEFF Research Database (Denmark)

    Barnkob, Mike Stein; Simon, Christian; Olsen, Lars Rønn

    2014-01-01

    In this study, we performed extensive semi-automated data collection from the primary and secondary literature in an effort to characterize the expression of all membrane proteins within the CD scheme on hematopoietic cells. Utilizing over 6000 data points across 305 CD molecules on 206 cell types......, we seek to give a preliminary characterization of the "human hematopoietic CDome." We encountered severe gaps in the knowledge of CD protein expression, mostly resulting from incomplete and unstructured data generation, which we argue inhibit both basic research as well as therapies seeking to target...

  16. Feedstock characterization and recommended procedures

    International Nuclear Information System (INIS)

    Using biomass for non-conventional applications such as feedstocks for fuels, chemicals, new materials, and electric power production requires knowledge of biomass characteristics important to these processes, and characterization techniques that are more appropriate than those employed today for conventional applications of food, feed, and fiber. This paper reviews feedstock characterization and standardization methodologies, and identifies research and development needs. It reviews the international cooperation involved in determining biomass characteristics and standards that has culminated in preparing four biomass samples currently available from the National Institute of Standards and Technology (NIST)

  17. Remote sensing for site characterization

    Science.gov (United States)

    Kuehn, Friedrich, (Edited By); King, Trude V.; Hoerig, Bernhard; Peters, Douglas C.

    2000-01-01

    This volume, Remote Sensing for Site Characterization, describes the feasibility of aircraft- and satellite-based methods of revealing environmental-geological problems. A balanced ratio between explanations of the methodological/technical side and presentations of case studies is maintained. The comparison of case studies from North America and Germany show how the respective territorial conditions lead to distinct methodological approaches.

  18. Raman spectroscopy for nanomaterials characterization

    CERN Document Server

    2012-01-01

    First volume of a 40-volume series on nanoscience and nanotechnology, edited by the renowned scientist Challa S.S.R. Kumar. This handbook gives a comprehensive overview about Raman spectroscopy for the characterization of nanomaterials. Modern applications and state-of-the-art techniques are covered and make this volume essential reading for research scientists in academia and industry.

  19. FCLib: The Feature Characterization Library.

    Energy Technology Data Exchange (ETDEWEB)

    Gentile, Ann C.; Doyle, Wendy S. K.; Kegelmeyer, W. Philip [Sandia National Laboratories, Livermore, CA; Ulmer, Craig D. [Sandia National Laboratories, Livermore, CA

    2008-11-01

    The Feature Characterization Library (FCLib) is a software library that simplifies the process of interrogating, analyzing, and understanding complex data sets generated by finite element applications. This document provides an overview of the library, a description of both the design philosophy and implementation of the library, and examples of how the library can be utilized to extract understanding from raw datasets.

  20. FTIR characterization of advanced materials

    Science.gov (United States)

    Young, P. R.; Chang, A. C.

    1986-01-01

    This paper surveys the application of Fourier transform infrared spectroscopy to the characterization of advanced materials. FTIR sampling techniques including internal and external reflectance and photoacoustic spectroscopy are discussed. Representative examples from the literature of the analysis of resins, fibers, prepregs and composites are reviewed. A discussion of several promising specialized FTIR techniques is also presented.

  1. Characterization of polyacrylonitrile ultrafiltration membranes

    OpenAIRE

    Germic, J.; Ebert, K.; Bouma, R.H.B.; Borneman, Z.; Mulder, M.H.V.; Strathmann, H.

    1997-01-01

    Various methods have been used to characterize ultrafiltration membranes, such as gas flux measurements, (field emission) scanning electron microscopy, permporometry and liquid-liquid displacement. Significant differences in the pore size distributions determined from permporometry and liquid-liquid displacement were found.

  2. A Mobile Automated Characterization System (MACS) for indoor floor characterization

    International Nuclear Information System (INIS)

    The Savannah River Technology Center (SRTC) and Oak Ridge National Laboratory are developing an advanced Mobile Automated Characterization System (MACS) to characterize indoor contaminated floors. MACS is based upon Semi-Intelligent Mobile Observing Navigator (SIMON), an earlier floor characterization system developed at SRTC. MACS will feature enhanced navigation systems, operator interface, and an interface to simplify integration of additional sensors. The enhanced navigation system will provide the capability to survey large open areas much more accurately than is now possible with SIMON, which is better suited for hallways and corridors that provide the means for recalibrating position and heading. MACS operator interface is designed to facilitate MACS's use as a tool for health physicists, thus eliminating the need for additional training in the robot's control language. Initial implementation of MACS will use radiation detectors. Additional sensors, such as PCB sensors currently being developed, will be integrated on MACS in the future. Initial use of MACS will be focused toward obtaining comparative results with manual methods. Surveys will be conducted both manually and with MACS to compare relative costs and data quality. While clear cost benefits anticipated, data quality benefits should be even more significant

  3. INFLUENCE OF ELECTROPOLYMERIZATION METHOD ON MORPHOLOGIES AND CAPACITIVE PROPERTIES OF POLYPYRROLE FILMS GROWING ON SILICON

    OpenAIRE

    IMENE CHIKOUCHE; ALI SAHARI; AHMED ZOUAOUI

    2014-01-01

    Two methods of Pyrrole electropolymerization were investigated to prepare polypyrrole films growing onto n-doped silicon n-Si (111): Polypyrrole films prepared by galvanostatic method exhibits toroidal morphology for thin films, and mixture of toroidal and globular morphologies for thick films. Polypyrrole films obtained from this method were characterized by lower surface roughness. Electropolymerization of pyrrole by potentiodynamic method provided Polypyrrole films with beans-like structur...

  4. Synthesis and structural characterization of anion complexes with azacalix[2]dipyrrolylmethane: effect of anion charge on the conformation of the macrocycle.

    Science.gov (United States)

    Guchhait, Tapas; Mani, Ganesan; Schulzke, Carola

    2016-08-01

    Tetrahomodiazacalix[2]dipyrrolylmethane 1, [-CH2(C4H3N)CR2(C4H3N)CH2N(Me)-]2 an expanded version of the calix[4]pyrrole system, has the tendency to change its ring conformation (1,3-alternate) upon anion binding analogous to calix[4]pyrrole. However, owing to its tertiary amine nitrogen atoms in the ring, it can be protonated and becomes a powerful cationic receptor for anions, besides its inherent hydrogen bonding features. Macrocycle 1 binds with a series of monoanions BF4(-), Cl(-), PhCOO(-) and ClO4(-), and their X-ray structures showed that the ring conformation constitutes the 1,2-alternate form. Upon binding with dianions SO4(2-), CrO4(2-), SiF6(2-) and S2O3(2-), the ring conformation changes to the cone conformation. The intermediate partial cone conformation results for complexes with NO3(-) and Cr2O7(2-) ions. The change in the orientation of the pyrrole NH groups depending on the charge of the anion demonstrates the flexibility of the macrocycle and the dicationic macrocycle stabilizes the anions via both hydrogen bonding and electrostatic interactions. PMID:27356484

  5. Synthesis, FT–IR characterization and crystal structure of aqua(5,10,15,20-tetraphenylporphyrinato-κ4Nmanganese(III trifluoromethanesulfonate

    Directory of Open Access Journals (Sweden)

    Wafa Harhouri

    2016-05-01

    Full Text Available In the title salt, [Mn(C44H28N4(H2O](CF3SO3 or [MnIII(TPP(H2O](CF3SO3 (where TPP is the dianion of 5,10,15,20-tetraphenylporphyrin, the MnIII cation is chelated by the four pyrrole N atoms of the porphyrinate anion and additionally coordinated by an aqua ligand in an apical site, completing the distorted square-pyramidal coordination environment. The average Mn—N(pyrrole bond length is 1.998 (9 Å and the Mn—O(aqua bond length is 2.1057 (15 Å. The central MnIII ion is displaced by 0.1575 (5 Å from the N4C20 mean plane of the porphyrinate anion towards the apical aqua ligand. The porphyrinate macrocycle exhibits a moderate ruffling and strong saddle deformations. In the crystal lattice, the [MnIII(TPP(H2O]+ cation and the trifluoromethanesulfonate counter-ions are arranged in alternating planes packed along [001]. The components are linked together through O—H...O hydrogen bonds and much weaker C—H...O and C—H...F interactions. The crystal packing is further stabilized by weak C—H...π interactions involving the pyrrole and phenyl rings of the porphyrin moieties.

  6. Aerosol characterization during project POLINAT

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, D.E.; Hopkins, A.R.; Paladino, J.D.; Whitefield, P.D. [Missouri Univ., Rolla, MO (United States). Cloud and Aerosol Sciences Lab.; Lilenfeld, H.V. [McDonnell Douglas Aerospace-East, St. Louis, MO (United States)

    1997-12-31

    The objectives of the aerosol/particulate characterization measurements of project POLINAT (POLlution from aircraft emissions In the North ATlantic flight corridor) are: to search for aerosol/particulate signatures of air traffic emissions in the region of the North Atlantic Flight Corridor; to search for the aerosol/particulate component of large scale enhancement (`corridor effects`) of air traffic related species in the North Atlantic region; to determine the effective emission indices for the aerosol/particulate component of engine exhaust in both the near and far field of aircraft exhaust plumes; to measure the dispersion and transformation of the aerosol/particulate component of aircraft emissions as a function of ambient condition; to characterize background levels of aerosol/particulate concentrations in the North Atlantic Region; and to determine effective emission indices for engine exhaust particulates for regimes beyond the jet phase of plume expansion. (author) 10 refs.

  7. Physical characterization of magmatic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Manghnani, M.H.

    1991-01-01

    Long-range goals of this research project are: (1) Characterization of seismic velocity and attenuation (V{sub p}, V{sub S}, Q{sub p}{sup {minus}1}, Q{sup S}{sup {minus}1}) and electrical properties of selected Hawaiian and related rocks under appropriate controlled environments of pressure, temperature and volatile/fluid content; and, (2) Characterization of the elastic, viscoelastic and thermodynamic properties (V{sub p}, V{sub S}, Q{sub P}{sup {minus}1}, Q{sub S}{sup {minus}1}, viscosity and compressibility) of molten basalts, picrites and komatites, and related silicate melts to {approximately} 1600{degrees}C using the ultrasonic interferometry method. In addition, the pressure dependences of V{sub p},V{sub S} and bulk modulus will be determined using the Brillouin scattering and diamond- anvil cell techniques.

  8. Surface characterization of ceramic materials

    International Nuclear Information System (INIS)

    In recent years several techniques have become available to characterize the structure and chemical composition of surfaces of ceramic materials. These techniques utilize electron scattering and scattering of ions from surfaces. Low-energy electron diffraction is used to determine the surface structure, Auger electron spectroscopy and other techniques of electron spectroscopy (ultraviolet and photoelectron spectroscopies) are employed to determine the composition of the surface. In addition the oxidation state of surface atoms may be determined using these techniques. Ion scattering mass spectrometry and secondary ion mass spectrometry are also useful in characterizing surfaces and their reactions. These techniques, their applications and the results of recent studies are discussed. 12 figures, 52 references, 2 tables

  9. Photoacoustic elastic oscillation and characterization

    CERN Document Server

    Gao, Fei; Zheng, Yuanjin

    2014-01-01

    Photoacoustic imaging and sensing have been studied extensively to probe the optical absorption of biological tissue in multiple scales ranging from large organs to small molecules. However, its elastic oscillation characterization is rarely studied and has been an untapped area to be explored. In literature, photoacoustic signal induced by pulsed laser is commonly modelled as a bipolar "N-shape" pulse from an optical absorber. In this paper, the photoacoustic damped oscillation is predicted and modelled by an equivalent mass-spring system by treating the optical absorber as an elastic oscillator. The photoacoustic simulation incorporating the proposed oscillation model shows better agreement with the measured signal from an elastic phantom, than conventional photoacoustic simulation model. More interestingly, the photoacoustic damping oscillation effect could potentially be a useful characterization approach to evaluate biological tissue's mechanical properties in terms of relaxation time, peak number and ra...

  10. AFIP-6 Characterization Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Dennis D. Keiser

    2011-12-01

    The AFIP-6 (ATR Full-size-plate In center flux trap Position) Characterization Summary Report outlines the fresh fuel characterization efforts performed during the AFIP-6 experiment. The AFIP-6 experiment was designed to evaluate the performance of monolithic uranium-molybdenum (U-Mo) fuels at a scale prototypic of Advanced Test Reactor (ATR) fuel plates (45-inches long). The AFIP-6 test was the first test with plates that were swaged into the rails of the assembly. This test served to examine the effects of a plate in a swaged condition with longer fuel zones (22.5-inches long), that were centered in the plate. AFIP-6 test plates employed a zirconium interlayer that was co-rolled with the fuel foil. Previous mini-plate and AFIP irradiation experiments performed in ATR have demonstrated the stable behavior of the interface between the U-Mo fuel and the zirconium interlayer.

  11. RF Characterization of Superconducting Samples

    CERN Document Server

    Junginger, T; Welsch, C

    2009-01-01

    At CERN a compact Quadrupole Resonator has been re-commissioned for the RF characterization of superconducting materials at 400 MHz. In addition the resonator can also be excited at multiple integers of this frequency. Besides Rs it enables determination of the maximum RF magnetic field, the thermal conductivity and the penetration depth of the attached samples, at different temperatures. The features of the resonator will be compared with those of similar RF devices and first results will be presented.

  12. Physicochemical characterization of Gozitan Honey

    OpenAIRE

    Everaldo Attard; Joseph Mizzi

    2013-01-01

    Honey quality is clearly defined in the EU Directive 2001/110/EC, and by Codex Alimentarius (Codex Stan 12-1981) and the International Honey Commission (IHC, 2002). Our investigation aimed to characterize the physicochemical properties of honey produced on a small island, Gozo which is situated near Malta.  Ten randomly collected honey samples were analysed for moisture content, pH, free acidity, water insoluble content, hydroxymethylfurfural (HMF) content and total phenolic compounds.  Moist...

  13. Some Characterizations of Krull Monoids

    Institute of Scientific and Technical Information of China (English)

    Hwankoo Kim; Myeong Og Kim; Young Soo Park

    2007-01-01

    In this paper,Kaplansky-type theorems are given to characterize GCD-monoids and valuation monoids.Also,(unique) r-factorable monoids are defined and it is shown that S is a Krull monoid if and only if S is a unique t-factorable (resp.,w-factorable)monoid if and only if S is a t-factorable (resp.,w-factorable) t-Pr(u)fer monoid.

  14. Temporary storage area characterization report

    International Nuclear Information System (INIS)

    The preferred alternative identified in the Remedial Investigation/Feasibility Study (RI/FS) for the Weldon Spring Quarry Bulk Wastes is to remove the wastes from the quarry and transport them by truck to temporary storage facility at the chemical plant site. To support the RI/FS, this report provides data to characterize the temporary storage area (TSA) site and to ensure the suitability of the proposed location. 31 refs., 14 figs., 7 tabs

  15. Characterization of hereditarily reversible posets

    OpenAIRE

    Kukieła, Michał

    2013-01-01

    A poset P is called reversible if every order preserving bijective self map of P is an order automorphism. P is called hereditarily reversible if every subposet of P is reversible. We give a complete characterization of hereditarily reversible posets in terms of forbidden subsets. A similar result is stated also for preordered sets. As a corollary we extend the list of known examples of hereditarily reversible topological spaces.

  16. Fabrication and Characterization of NEMS

    Institute of Scientific and Technical Information of China (English)

    JIAO Ji-wei; YANG Heng; LI Tie; LI Xin-xin; WANG Yue-lin

    2007-01-01

    We proposed a called "nano-fabrication based on MEMS technology" approach to realize the typical nano-electromechanical structures,such as integrated nano probe,ultrathin cantilever,silicon nano wire,and doubly clamped nano beam,to demonstrate the feasibility and advantages. We also introduced the characterization of nano structures based on laser vibrometer and piezoresistive effect,the latter method was first time applied to investigate a doubly daped nanobeam with a thickness of about 200 nm.

  17. Characterization of Human Thymic Exosomes

    OpenAIRE

    Gabriel Skogberg; Judith Gudmundsdottir; Sjoerd van der Post; Kerstin Sandström; Sören Bruhn; Mikael Benson; Lucia Mincheva-Nilsson; Vladimir Baranov; Esbjörn Telemo; Olov Ekwall

    2013-01-01

    Exosomes are nanosized membrane-bound vesicles that are released by various cell types and are capable of carrying proteins, lipids and RNAs which can be delivered to recipient cells. Exosomes play a role in intercellular communication and have been described to mediate immunologic information. In this article we report the first isolation and characterization of exosomes from human thymic tissue. Using electron microscopy, particle size determination, density gradient measurement, flow cytom...

  18. Towards Characterizing International Routing Detours

    OpenAIRE

    Shah, Anant; Fontunge, Romain; Papadopoulos, Christos

    2016-01-01

    There are currently no requirements (technical or otherwise) that BGP paths must be contained within national boundaries. Indeed, some paths experience international detours, i.e., originate in one country, cross international boundaries and return to the same country. In most cases these are sensible traffic engineering or peering decisions at ISPs that serve multiple countries. In some cases such detours may be suspicious. Characterizing international detours is useful to a number of player...

  19. Cross delay line sensor characterization

    Energy Technology Data Exchange (ETDEWEB)

    Owens, Israel J [Los Alamos National Laboratory; Remelius, Dennis K [Los Alamos National Laboratory; Tiee, Joe J [Los Alamos National Laboratory; Buck, Steven E [Los Alamos National Laboratory; Whittemore, Stephen R [Los Alamos National Laboratory; Thompson, David C [Los Alamos National Laboratory; Shirey, Robert [Los Alamos National Laboratory

    2010-01-01

    There exists a wealth of information in the scientific literature on the physical properties and device characterization procedures for complementary metal oxide semiconductor (CMOS), charge coupled device (CCD) and avalanche photodiode (APD) format detectors. Numerous papers and books have also treated photocathode operation in the context of photomultiplier tube (PMT) operation for either non imaging applications or limited night vision capability. However, much less information has been reported in the literature about the characterization procedures and properties of photocathode detectors with novel cross delay line (XDL) anode structures. These allow one to detect single photons and create images by recording space and time coordinate (X, Y & T) information. In this paper, we report on the physical characteristics and performance of a cross delay line anode sensor with an enhanced near infrared wavelength response photocathode and high dynamic range micro channel plate (MCP) gain (> 10{sup 6}) multiplier stage. Measurement procedures and results including the device dark event rate (DER), pulse height distribution, quantum and electronic device efficiency (QE & DQE) and spatial resolution per effective pixel region in a 25 mm sensor array are presented. The overall knowledge and information obtained from XDL sensor characterization allow us to optimize device performance and assess capability. These device performance properties and capabilities make XDL detectors ideal for remote sensing field applications that require single photon detection, imaging, sub nano-second timing response, high spatial resolution (10's of microns) and large effective image format.

  20. Sustainability Characterization for Additive Manufacturing.

    Science.gov (United States)

    Mani, Mahesh; Lyons, Kevin W; Gupta, S K

    2014-01-01

    Additive manufacturing (AM) has the potential to create geometrically complex parts that require a high degree of customization, using less material and producing less waste. Recent studies have shown that AM can be an economically viable option for use by the industry, yet there are some inherent challenges associated with AM for wider acceptance. The lack of standards in AM impedes its use for parts production since industries primarily depend on established standards in processes and material selection to ensure the consistency and quality. Inability to compare AM performance against traditional manufacturing methods can be a barrier for implementing AM processes. AM process sustainability has become a driver due to growing environmental concerns for manufacturing. This has reinforced the importance to understand and characterize AM processes for sustainability. Process characterization for sustainability will help close the gaps for comparing AM performance to traditional manufacturing methods. Based on a literature review, this paper first examines the potential environmental impacts of AM. A methodology for sustainability characterization of AM is then proposed to serve as a resource for the community to benchmark AM processes for sustainability. Next, research perspectives are discussed along with relevant standardization efforts. PMID:26601038

  1. Ultrasonic Characterization of Aerospace Composites

    Science.gov (United States)

    Leckey, Cara; Johnston, Patrick; Haldren, Harold; Perey, Daniel

    2015-01-01

    Composite materials have seen an increased use in aerospace in recent years and it is expected that this trend will continue due to the benefits of reduced weight, increased strength, and other factors. Ongoing work at NASA involves the investigation of the large-scale use of composites for spacecraft structures (SLS components, Orion Composite Crew Module, etc). NASA is also involved in work to enable the use of composites in advanced aircraft structures through the Advanced Composites Project (ACP). In both areas (space and aeronautics) there is a need for new nondestructive evaluation and materials characterization techniques that are appropriate for characterizing composite materials. This paper will present an overview of NASA's needs for characterizing aerospace composites, including a description of planned and ongoing work under ACP for the detection of composite defects such as fiber waviness, reduced bond strength, delamination damage, and microcracking. The research approaches include investigation of angle array, guided wave, and phase sensitive ultrasonic methods. The use of ultrasonic simulation tools for optimizing and developing methods will also be discussed.

  2. Sofia Observatory Performance and Characterization

    Science.gov (United States)

    Temi, Pasquale; Miller, Walter; Dunham, Edward; McLean, Ian; Wolf, Jurgen; Becklin, Eric; Bida, Tom; Brewster, Rick; Casey, Sean; Collins, Peter; Jakob, Holger; Killebrew, Jana; Lampater, Ulrich; Mandushev, Georgi; Marcum, Pamela; Meyer, Allan; Pfueller, Enrico; Reinacher, Andreas; Roeser, Hans-Peter; Savage, Maureen; Teufel, Stefan; Wiedemann, Manuel

    2012-01-01

    The Stratospheric Observatory for Infrared Astronomy (SOFIA) has recently concluded a set of engineering flights for Observatory performance evaluation. These in-flight opportunities have been viewed as a first comprehensive assessment of the Observatory's performance and will be used to address the development activity that is planned for 2012, as well as to identify additional Observatory upgrades. A series of 8 SOFIA Characterization And Integration (SCAI) flights have been conducted from June to December 2011. The HIPO science instrument in conjunction with the DSI Super Fast Diagnostic Camera (SFDC) have been used to evaluate pointing stability, including the image motion due to rigid-body and flexible-body telescope modes as well as possible aero-optical image motion. We report on recent improvements in pointing stability by using an Active Mass Damper system installed on Telescope Assembly. Measurements and characterization of the shear layer and cavity seeing, as well as image quality evaluation as a function of wavelength have been performed using the HIPO+FLITECAM Science Instrument configuration (FLIPO). A number of additional tests and measurements have targeted basic Observatory capabilities and requirements including, but not limited to, pointing accuracy, chopper evaluation and imager sensitivity. SCAI activities included in-flight partial Science Instrument commissioning prior to the use of the instruments as measuring engines. This paper reports on the data collected during the SCAI flights and presents current SOFIA Observatory performance and characterization.

  3. Instrumentation for CTA site characterization

    CERN Document Server

    Fruck, Christian; Ernenwein, Jean-Pierre; Mandát, Dušan; Schweizer, Thomas; Häfner, Dennis; Bulik, Tomasz; Cieslar, Marek; Costantini, Heide; Dominik, Michal; Ebr, Jan; Garczarczyk, Markus; Lorentz, Eckart; Pareschi, Giovanni; Pech, Miroslav; Puerto-Giménez, Irene; Teshima, Masahiro

    2015-01-01

    Many atmospheric and climatic criteria have to be taken into account for the selection of a suitable site for the next generation of imaging air-shower Cherenkov telescopes, the "Cherenkov Telescope Array" CTA. Such data are not available with sufficient precision or the comparability to allow for a comprehensive characterization of the proposed sites to be made. Identical cross-calibrated instruments have been developed which allow for precise comparison between sites, the cross-validation of existing data, and the ground-validation of satellite data. The site characterization work package of the CTA consortium opted to construct and deploy 9 copies of an autonomous multi-purpose weather sensor, incorporating an infrared cloud sensor a newly developed sensor for measuring the light of the night sky, and an All-Sky-Camera, the whole referred to as Autonomous Tool for Measuring Observatory Site COnditions PrEcisely (ATMOSCOPE). We present here the hardware that was combined into the ATMOSCOPE and characterize ...

  4. Characterization system for resonant micro- and nanocantilevers

    DEFF Research Database (Denmark)

    Sandberg, Rasmus Kousholt; Boisen, Anja; Svendsen, Winnie Edith

    2005-01-01

    We present a system for characterization of the resonant properties of micro- and nanocantilever sensors. The system has been constructed as a vacuum chamber with capabilities for controlling environmental conditions such as pressure, temperature, and chemical constituents. Characterization can...

  5. Some Characterizations of Mixed Poisson Processes

    CERN Document Server

    Lyberopoulos, D P

    2011-01-01

    A characterization of mixed Poisson processes in terms of disintegrations is proven. As a consequence some further characterizations of such processes via claim interarrival processes, martingales and claim measures are obtained.

  6. NCL Objective #3 - Nanotechnology Characterization Lab (NCL)

    Science.gov (United States)

    The Nanotechnology Characterization Lab (NCL) Objective #3: Identify and Characterize Critical Parameters Related to Nanomaterials' Absorption, Distribution, Metabolism, Excretion, and Acute Toxicity (ADME/Tox) Profile in Animal Models.

  7. Probabilistic Meteorological Characterization for Turbine Loads

    DEFF Research Database (Denmark)

    Kelly, Mark C.; Larsen, Gunner Chr.; Dimitrov, Nikolay Krasimirov;

    2014-01-01

    Beyond the existing, limited IEC prescription to describe fatigue loads on wind turbines, we look towards probabilistic characterization of the loads via analogous characterization of the atmospheric flow, particularly for today's "taller" turbines with rotors well above the atmospheric surface...

  8. Gas characterization system software acceptance test report

    International Nuclear Information System (INIS)

    This document details the results of software acceptance testing of gas characterization systems. The gas characterization systems will be used to monitor the vapor spaces of waste tanks known to contain measurable concentrations of flammable gases

  9. Gas characterization system software acceptance test procedure

    International Nuclear Information System (INIS)

    This document details the Software Acceptance Testing of gas characterization systems. The gas characterization systems will be used to monitor the vapor spaces of waste tanks known to contain measurable concentrations of flammable gases

  10. Synthesis and characterization of copper, polyimide and TIPS-pentacene layers for the development of a solution processed fibrous transistor

    Directory of Open Access Journals (Sweden)

    B. Van Genabet

    2011-12-01

    Full Text Available A study was performed for the development of a flexible organic field effect transistor starting from a polyester fibre as substrate material. Focus of subsequent layer deposition was on low temperature soluble processes to allow upscaling. Gate layer consists out of a pyrrole polymerization and copper coating step. Polyimide dielectric layer was deposited using dipcoating. Gold electrodes were vacuum evaporated and patterned via mask fibre shadowing. The active layer consisted of a soluble p-type TIPS-pentacene organic semiconductor. Different deposition techniques have been examined. Considerable progress in development of a transistor has been made.

  11. 10 CFR 60.15 - Site characterization.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Site characterization. 60.15 Section 60.15 Energy NUCLEAR... Preapplication Review § 60.15 Site characterization. (a) Prior to submittal of an application for a license to be issued under this part DOE shall conduct a program of site characterization with respect to the site...

  12. 10 CFR 63.15 - Site characterization.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Site characterization. 63.15 Section 63.15 Energy NUCLEAR... MOUNTAIN, NEVADA Licenses Preapplication Review § 63.15 Site characterization. (a) DOE shall conduct a program of site characterization with respect to the Yucca Mountain site before it submits an...

  13. The Rings Characterized by Minimal Left Ideals

    Institute of Scientific and Technical Information of China (English)

    Jun Chao WEI

    2005-01-01

    We study these rings with every minimal left ideal being a projective, direct summand and a p-injective module, respectively. Some characterizations of these rings are given, and the relations among them are obtained. With these rings, we characterize semisimple rings. Finally, we introduce MC2 rings, and give some characterizations of MC2 rings.

  14. A Characterization of the Negative Binomial Distribution

    OpenAIRE

    Kolev, Nikolay(Department of Physics, University of Regina, SK S4S 0A2, Canada); Minkova, Leda

    2000-01-01

    Only a few characterizations have been obtained in literatute for the negative binomial distribution (see Johnson et al., Chap. 5, 1992). In this article a characterization of the negative binomial distribution related to random sums is obtained which is motivated by the geometric distribution characterization given by Khalil et al. (1991). An interpretation in terms of an unreliable system is given.

  15. Instrumentation for tropospheric aerosol characterization

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Z.; Young, S.E.; Becker, C.H.; Coggiola, M.J. [SRI International, Menlo Park, CA (United States); Wollnik, H. [Giessen Univ. (Germany)

    1997-12-31

    A new instrument has been developed that determines the abundance, size distribution, and chemical composition of tropospheric and lower stratospheric aerosols with diameters down to 0.2 {mu}m. In addition to aerosol characterization, the instrument also monitors the chemical composition of the ambient gas. More than 25.000 aerosol particle mass spectra were recorded during the NASA-sponsored Subsonic Aircraft: Contrail and Cloud Effects Special Study (SUCCESS) field program using NASA`s DC-8 research aircraft. (author) 7 refs.

  16. Characterization of liquid scintillation detectors

    CERN Document Server

    Schmidt, D; Böttger, R; Klein, H; Lebreton, L; Neumann, S; Nolte, R; Pichenot, G

    2002-01-01

    Five scintillation detectors of different scintillator size and type were characterized. The pulse height scale was calibrated in terms of electron light output units using photon sources. The response functions for time-of-flight (TOF)-selected monoenergetic neutrons were experimentally determined and also simulated with the NRESP code over a wide energy range. A comparison of the measured and calculated response functions allows individual characteristics of the detectors to be determined and the response matrix to be reliably derived. Various applications are discussed.

  17. Petroleum characterization by perfluorocarbon tracers

    Energy Technology Data Exchange (ETDEWEB)

    Senum, G.I.; Fajer, R.W. (Brookhaven National Lab., Upton, NY (United States)); Harris, B.R. Jr. (USDOE Naval Petroleum Reserves in California, Tupman, CA (United States)); DeRose, W.E. (Bechtel Petroleum Operations, Inc., Tupman, CA (United States)); Ottaviani, W.L. (Chevron U.S.A., Inc., Bakersfield, CA (United States))

    1992-02-01

    Perfluorocarbon tracers (PFTs), a class of six compounds, were used to help characterize the Shallow Oil Zone (SOZ) reservoir at the Naval Petroleum Reserve in California (NPRC) at Elk Hills. The SOZ reservoir is undergoing a pilot gas injection program to assess the technical feasibility and economic viability of injecting gas into the SOZ for improved oil recovery. PFTs were utilized in the pilot gas injection to qualitatively assess the extent of the pilot gas injection so as to determine the degree of gas containment within the SOZ reservoir.

  18. Advanced Fine Particulate Characterization Methods

    Energy Technology Data Exchange (ETDEWEB)

    Steven Benson; Lingbu Kong; Alexander Azenkeng; Jason Laumb; Robert Jensen; Edwin Olson; Jill MacKenzie; A.M. Rokanuzzaman

    2007-01-31

    The characterization and control of emissions from combustion sources are of significant importance in improving local and regional air quality. Such emissions include fine particulate matter, organic carbon compounds, and NO{sub x} and SO{sub 2} gases, along with mercury and other toxic metals. This project involved four activities including Further Development of Analytical Techniques for PM{sub 10} and PM{sub 2.5} Characterization and Source Apportionment and Management, Organic Carbonaceous Particulate and Metal Speciation for Source Apportionment Studies, Quantum Modeling, and High-Potassium Carbon Production with Biomass-Coal Blending. The key accomplishments included the development of improved automated methods to characterize the inorganic and organic components particulate matter. The methods involved the use of scanning electron microscopy and x-ray microanalysis for the inorganic fraction and a combination of extractive methods combined with near-edge x-ray absorption fine structure to characterize the organic fraction. These methods have direction application for source apportionment studies of PM because they provide detailed inorganic analysis along with total organic and elemental carbon (OC/EC) quantification. Quantum modeling using density functional theory (DFT) calculations was used to further elucidate a recently developed mechanistic model for mercury speciation in coal combustion systems and interactions on activated carbon. Reaction energies, enthalpies, free energies and binding energies of Hg species to the prototype molecules were derived from the data obtained in these calculations. Bimolecular rate constants for the various elementary steps in the mechanism have been estimated using the hard-sphere collision theory approximation, and the results seem to indicate that extremely fast kinetics could be involved in these surface reactions. Activated carbon was produced from a blend of lignite coal from the Center Mine in North Dakota and

  19. Characterization of Mexican zeolite minerals

    International Nuclear Information System (INIS)

    50% of the Mexican territory is formed by volcanic sequences of the Pliocene type, which appear extensively in the northwest states (Sonora, Sinaloa, Chihuahua, Durango) and west of Mexico (Jalisco and Nayarit), in central Mexico (Zacatecas, Guanajuato, San Luis Potosi, Queretaro, Hidalgo) and south of Mexico (Guerrero, Oaxaca); therefore, it is to be expected that in our country big locations of natural zeolites exist in its majority of the clinoptilolite type. The present study was focused toward the characterization of two Mexican natural zeolite rocks presumably of the clinoptilolite and filipsite types, one of them comes from the state of Chihuahua and the other of a trader company of non metallic minerals, due that these materials are not characterized, its are not known their properties completely and therefore, the uses that can be given to these materials. In this investigation work it was carried out the characterization of two Mexican zeolite rocks, one coming from the Arroyo zone, municipality of La Haciendita, in the state of Chihuahua; and the other one was bought to a trader company of non metallic minerals. The two zeolites so much in their natural form as conditioned with sodium; they were characterized by means of X-ray diffraction, scanning electron microscopy of high vacuum and elementary microanalysis (EDS), surface area analysis (BET), thermal gravimetric analysis. To differentiate the heulandite crystalline phase of the other clinoptilolite rock, its were carried out thermal treatments. The quantification of Al, Na, Ca, K, Mg, Fe was carried out in solution, by means of atomic absorption spectroscopy and the quantity of Si was determined by gravimetry. The zeolite rocks presented for the major part the crystalline heulandite and clinoptilolite phases for the most part, and it was found that the zeolite coming from the state of Chihuahua possesses a bigger content of heulandite and the denominated filipsite it is really a zeolite

  20. FNAS materials processing and characterization

    Science.gov (United States)

    Golben, John P.

    1991-01-01

    Research on melt-sintered high temperature superconducting materials is presented. The vibrating sample magnetometer has become a useful characterization tool for the study of high temperature superconductors. Important information regarding the superconducting properties of a sample can be obtained without actually making contact with the sample itself. A step toward microgravity processing of high temperature superconductors was taken. In the future, the samples need to be optimized prior to this processing of the sample before the specific effects of the microgravity environment can be isolated. A series of melt-sintered samples show that bulk processing of high temperature superconductors is getting better.

  1. Manganese borohydride; synthesis and characterization

    OpenAIRE

    Richter, Bo; Ravnsbæk, Dorthe B.; Tumanov, Nikolay; Filinchuk, Yaroslav; Jensen, Torben R.

    2015-01-01

    Solvent-based synthesis and characterization of α-Mn(BH4)2 and a new nanoporous polymorph of manganese borohydride, γ-Mn(BH4)2, via a new solvate precursor, Mn(BH4)2·1/2S(CH3)2, is presented. Manganese chloride is reacted with lithium borohydride in a toluene/dimethylsulfide mixture at room temperature, which yields halide and solvent-free manganese borohydride after extraction with dimethylsulfide (DMS) and subsequent removal of residual solvent. This work constitutes the first example of es...

  2. Neutron Characterization for Additive Manufacturing

    Science.gov (United States)

    Watkins, Thomas; Bilheux, Hassina; An, Ke; Payzant, Andrew; DeHoff, Ryan; Duty, Chad; Peter, William; Blue, Craig; Brice, Craig A.

    2013-01-01

    Oak Ridge National Laboratory (ORNL) is leveraging decades of experience in neutron characterization of advanced materials together with resources such as the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR) shown in Fig. 1 to solve challenging problems in additive manufacturing (AM). Additive manufacturing, or three-dimensional (3-D) printing, is a rapidly maturing technology wherein components are built by selectively adding feedstock material at locations specified by a computer model. The majority of these technologies use thermally driven phase change mechanisms to convert the feedstock into functioning material. As the molten material cools and solidifies, the component is subjected to significant thermal gradients, generating significant internal stresses throughout the part (Fig. 2). As layers are added, inherent residual stresses cause warping and distortions that lead to geometrical differences between the final part and the original computer generated design. This effect also limits geometries that can be fabricated using AM, such as thin-walled, high-aspect- ratio, and overhanging structures. Distortion may be minimized by intelligent toolpath planning or strategic placement of support structures, but these approaches are not well understood and often "Edisonian" in nature. Residual stresses can also impact component performance during operation. For example, in a thermally cycled environment such as a high-pressure turbine engine, residual stresses can cause components to distort unpredictably. Different thermal treatments on as-fabricated AM components have been used to minimize residual stress, but components still retain a nonhomogeneous stress state and/or demonstrate a relaxation-derived geometric distortion. Industry, federal laboratory, and university collaboration is needed to address these challenges and enable the U.S. to compete in the global market. Work is currently being conducted on AM technologies at the ORNL

  3. Multifractal approach for seafloor characterization

    Digital Repository Service at National Institute of Oceanography (India)

    Chakraborty, B.; Haris, K.; Latha, G.; Maslov, N.; Menezes, A.A.A.

    . [14] B. Chakraborty, V. Mahale, C. de Sousa, and P. Das, ‘Seafloor classification using echo- waveforms: a method employing hybrid neural network architecture,’ IEEE Geosci. Remote Sens. Lett., vol. 1, no. 3, pp. 196-200, Jul. 2004. [15] C. De and B.... Chakraborty, ‘Acoustic characterization of seafloor sediment employing a hybrid method of neural network architecture and fuzzy algorithm,’ IEEE Geosci. Remote Sens. Lett., vol. 6, no. 4, pp. 743-747, Oct. 2009. [16] A. B. Chhabra and R. V. Jensen, ‘Direct...

  4. Acoustic characterization of rehabilitated cloisters

    OpenAIRE

    A. P. O. Carvalho; S. R. C. Vilela

    2008-01-01

    This paper presents the results of field measurements in eight rehabilitated cloisters of old monasteries in Portugal (length: 20 to 35 m and height: 3.3 to 6.3 m) regarding their acoustic behavior to two objective parameters: RT and RASTI. The goal is to characterize the acoustic effect of the rehabilitation done on theses spaces to adapt them to new uses. All these cloisters had recently their galleries#8217; openings to the central yard closed with glass panels. Simple formulas were obtain...

  5. Active thermography for potato characterization

    Science.gov (United States)

    Hsieh, Sheng-Jen; Sun, Chih-Chen

    2008-03-01

    This paper describes the design of a semi-automated heating and scanning system and analytic method for potato characterization. Potatoes are heated using lamps in a heating chamber and then transferred on a movable fixture to an imaging chamber. A non-linear model was designed to predict which potatoes have excessive sugar defects and the model was evaluated with good results. Results from this research will benefit potato growers and manufacturers/producers of potato-based products such as chips and fries.

  6. Synthesis and characterization of titanium dioxide nanomaterials for photocatalytic hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Kandiel, Tarek Abdel-Saman Abdel-Rahman

    2010-07-20

    The photocatalytic molecular hydrogen (H{sub 2}) production from aqueous methanol solutions over Pt-loaded commercial (Evonik Aeroxide TiO{sub 2} P25 and Sachtleben Hombikat UV100) and home made (TiO{sub 2} P25HT) titanium dioxide nanomaterials has been studied. The photonic efficiencies were calculated by dividing the H{sub 2} production rate by the photon flux. The effect of the employed light intensity on the photocatalytic H{sub 2} production rate was investigated. The products of the photocatalytic methanol oxidation were quantitatively analyzed employing different test conditions, i.e., different illumination times, pH values, and methanol concentrations. The balance between the amount of evolved H{sub 2} and the amount of methanol photooxidation products has been tested. Besides Pt, TiO{sub 2} was also modified with Pt-polypyrrole nanocomposites through the in situ simultaneous reduction of Pt(IV) and the oxidative polymerization of pyrrole monomers at ambient temperature. The modified powders were characterized using X-ray photoelectron spectroscopy, dark-field scanning transmission electron microscopy, infrared spectroscopy, and by the determination of the BET surface area by nitrogen adsorption. The photocatalytic H{sub 2} production over these newly modified TiO{sub 2} nanomaterials has been investigated and compared with that of TiO{sub 2} modified with Pt islands prepared via a photochemical deposition method. TiO{sub 2} rutile nanorods either decorated with anatase nanoparticles or pure have been prepared via a facile single-step hydrothermal method using commercially available aqueous solutions of titanium(IV) bis(ammoniumlactate) dihydroxide at natural pH ({proportional_to} 8.0) without any additives. The obtained powders have been characterized by X-ray diffraction, field-emission scanning electron microscopy, high-resolution transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy, and by nitrogen adsorption. These newly prepared

  7. Historical characterization of trigeminal neuralgia.

    Science.gov (United States)

    Eboli, Paula; Stone, James L; Aydin, Sabri; Slavin, Konstantin V

    2009-06-01

    TRIGEMINAL NEURALGIA IS a well known clinical entity characterized by agonizing, paroxysmal, and lancinating facial pain, often triggered by movements of the mouth or eating. Historical reviews of facial pain have attempted to describe this severe pain over the past 2.5 millennia. The ancient Greek physicians Hippocrates, Aretaeus, and Galen, described kephalalgias, but their accounts were vague and did not clearly correspond with what we now term trigeminal neuralgia. The first adequate description of trigeminal neuralgia was given in 1671, followed by a fuller description by physician John Locke in 1677. André described the convulsive-like condition in 1756, and named it tic douloureux; in 1773, Fothergill described it as "a painful affection of the face;" and in 1779, John Hunter more clearly characterized the entity as a form of "nervous disorder" with reference to pain of the teeth, gums, or tongue where the disease "does not reside." One hundred fifty years later, the neurological surgeon Walter Dandy equated neurovascular compression of the trigeminal nerve with trigeminal neuralgia.

  8. Solar Filament Extraction and Characterizing

    Science.gov (United States)

    Yuan, Yuan; Shih, F. Y.; Jing, J.; Wang, H.

    2010-05-01

    This paper presents a new method to extract and characterize solar filaments from H-alpha full-disk images produced by Big Bear Solar Observatory. A cascading Hough Transform method is designed to identify solar disk center location and radius. Solar disks are segmented from the background, and unbalanced illumination on the surface of solar disks is removed using polynomial surface fitting. And then a localized adaptive thresholding is employed to extract solar filament candidates. After the removal of small solar filament candidates, the remaining larger candidates are used as the seeds of region growing. The procedure of region growing not only connects broken filaments but also generate complete shape for each filament. Mathematical morphology thinning is adopted to produce the skeleton of each filament, and graph theory is used to prune branches and barbs to get the main skeleton. The length and the location of the main skeleton is characterized. The proposed method can help scientists and researches study the evolution of solar filament, for instance, to detect solar filament eruption. The presented method has already been used by Space Weather Research Lab of New Jersey Institute of Technology (http://swrl.njit.edu) to generate the solar filament online catalog using H-alpha full-disk images of Global H-alpha Network (http://swrl.njit.edu/ghn_web/).

  9. Quantitative Characterization of Nanostructured Materials

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Frank (Bud) Bridges, University of California-Santa Cruz

    2010-08-05

    The two-and-a-half day symposium on the "Quantitative Characterization of Nanostructured Materials" will be the first comprehensive meeting on this topic held under the auspices of a major U.S. professional society. Spring MRS Meetings provide a natural venue for this symposium as they attract a broad audience of researchers that represents a cross-section of the state-of-the-art regarding synthesis, structure-property relations, and applications of nanostructured materials. Close interactions among the experts in local structure measurements and materials researchers will help both to identify measurement needs pertinent to real-world materials problems and to familiarize the materials research community with the state-of-the-art local structure measurement techniques. We have chosen invited speakers that reflect the multidisciplinary and international nature of this topic and the need to continually nurture productive interfaces among university, government and industrial laboratories. The intent of the symposium is to provide an interdisciplinary forum for discussion and exchange of ideas on the recent progress in quantitative characterization of structural order in nanomaterials using different experimental techniques and theory. The symposium is expected to facilitate discussions on optimal approaches for determining atomic structure at the nanoscale using combined inputs from multiple measurement techniques.

  10. BNFL Report Glass Formers Characterization

    International Nuclear Information System (INIS)

    The objective of this task was to obtain powder property data on candidate glass former materials, sufficient to guide conceptual design and estimate the cost of glass former handling facilities as requested under Part B1 of BNFL Technical and Development Support. Twenty-nine glass forming materials were selected and obtained from vendors for the characterization of their physical properties, durability in caustic solution, and powder flow characteristics. A glass former was selected based on the characterization for each of the ten oxide classes required for Envelope A, B, and C mixtures. Three blends (A, B, and C) were prepared based on formulations provided by Vitreous State Laboratory and evaluated with the same methods employed for the glass formers. The properties obtained are presented in a series of attached Tables. It was determined that five of the ten glass formers, (kyanite, iron oxide, titania, zircon, and zinc oxide) have the potential to cause some level of solids f low problems. The problems might include arching or ratholing in the silo/hopper. In addition, all of the blends may require consideration for their handling

  11. Characterization and Metrology for Nanoelectronics

    Science.gov (United States)

    Diebold, Alain C.

    2007-09-01

    Despite the challenges associated with the cost and technological innovation, the semiconductor industry has introduced nanoelectronics into the market place. By extending traditional CMOS (complimentary metal oxide semiconductor transistors) through new materials in both the devices and on-chip interconnect, planar CMOS is already manufactured with transistor gate lengths less than 50 nm. Further extending CMOS will not only require new materials, but it may also drive the use of new non-planar device structures for transistors and new approaches for on and off-chip interconnection. At some point, CMOS extension may no longer be possible, and then a new switch would be necessary. The transition between CMOS extension and planar CMOS could involve the gradual incorporation of Beyond CMOS technology. The number of candidates continues to grow even as some possible technology is removed from consideration. Characterization and Metrology is finding each step in this transition to be a great challenge. This paper overviews the characterization and metrology necessary for both CMOS extension and beyond CMOS semiconductor technology. The International Technology Roadmap for Semiconductors is used a guide that provides a roadmap for both metrology and process technology that extends to beyond CMOS materials and devices.(1)

  12. Characterization of soils containing adipocere.

    Science.gov (United States)

    Fiedler, S; Schneckenberger, K; Graw, M

    2004-11-01

    The formation of adipocere (commonly known as grave wax), a spontaneous inhibition of postmortem changes, has been extensively analyzed in forensic science. However, soils in which adipocere formation occurs have never been described in detail. Therefore, this study is intended as a first step in the characterization of soils containing adipocere. Two grave soils (Gleyic Anthrosols) that prevent the timely reuse of graves due to the occurrence of adipocere and a control soil (Gleyic Luvisol) were selected from a cemetery in the Central Black Forest (Southwest Germany). Descriptions of soil morphology and a wide assay of physical, chemical, and microbiologic soil characteristics were accomplished. In contrast to the control soil, the grave soils were characterized by lower bulk density and pH. The degradation of the soil structure caused by digging led to a higher water table and the expansion of the reducing conditions in the graves where the prevalent absence of oxygen in range of the coffins inhibited decomposition processes. Although the formation of adipocere led to the conservation of the buried corpses, phosphorus, dissolved organic carbon, and cadavarine leaching from the graves was observed. Microbial biomass and microbial activity were higher in the control soil and hence reflected the inert character of adipocere. The study results clearly show the need for additional approaches in forensic, pedologic, and microbiologic research. PMID:15499507

  13. BNFL Report Glass Formers Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Schumacher, R.F.

    2000-07-27

    The objective of this task was to obtain powder property data on candidate glass former materials, sufficient to guide conceptual design and estimate the cost of glass former handling facilities as requested under Part B1 of BNFL Technical and Development Support. Twenty-nine glass forming materials were selected and obtained from vendors for the characterization of their physical properties, durability in caustic solution, and powder flow characteristics. A glass former was selected based on the characterization for each of the ten oxide classes required for Envelope A, B, and C mixtures. Three blends (A, B, and C) were prepared based on formulations provided by Vitreous State Laboratory and evaluated with the same methods employed for the glass formers. The properties obtained are presented in a series of attached Tables. It was determined that five of the ten glass formers, (kyanite, iron oxide, titania, zircon, and zinc oxide) have the potential to cause some level of solids f low problems. The problems might include arching or ratholing in the silo/hopper. In addition, all of the blends may require consideration for their handling.

  14. BNFL Report Glass Formers Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Schumacher, R.F.

    2000-07-27

    The objective of this task was to obtain powder property data on candidate glass former materials, sufficient to guide conceptual design and estimate the cost of glass former handling facilities as requested under Part B1 of BNFL Technical and Development Support. Twenty-nine glass forming materials were selected and obtained from vendors for the characterization of their physical properties, durability in caustic solution, and powder flow characteristics. A glass former was selected based on the characterization for each of the ten oxide classes required for Envelope A, B, and C mixtures. Three blends (A, B, and C) were prepared based on formulations provided by Vitreous State Laboratory and evaluated with the same methods employed for the glass formers. The properties obtained are presented in a series of attached Tables. It was determined that five of the ten glass formers, (kyanite, iron oxide, titania, zircon, and zinc oxide) have the potential to cause some level of solids f low problems. In addition, all of the blends may require consideration for their handling. A number of engineering considerations and recommendations were prepared based on the experimental findings, experience, and other process considerations. Recommendations for future testing are included. In conjunction with future work, it is recommended that a professional consultant be engaged to guide and assist with testing and design input.

  15. Characterization of Polymeric Nanofiltration Membranes

    Directory of Open Access Journals (Sweden)

    Simoncic, B.

    2007-11-01

    Full Text Available As membrane processes are increasingly used in industrial applications, there is a growing interest in methods of membrane characterization. Traditional membrane characteristics, such as cut-off value and pore size distribution, are being supplemented by membrane surface characteristics, such as charge density or zeta potential and hydrophobicity. This study, therefore, characterizes the three different polymeric membranes used (NFT-50, DL and DK. The molecular mass cut-off (MMCO value was determined using a set of reference solutes within the molecular range 150-600 Da, whereas streaming potential measurements enabled quantification of the surface charge characteristics. Hydrophobicity was studied using contact angle measurements. The results indicated that even though all three membranes had very similar layer compositions which consisted of poly(piperazneamide, as top layers they showed different values of measured quantitive. The NFT-50 membrane had the lowest MMCO value and the most hydrophilic membrane surface, followed by DK and DL. Membrane fouling as measured by flux reduction was determined by streaming potential measurements and accompanied by a positive change in zeta potential.

  16. Characterization of minerals, metals and materials

    CERN Document Server

    Hwang, Jiann-Yang; Bai, Chengguang; Carpenter, John; Cai, Mingdong; Firrao, Donato; Kim, Byoung-Gon

    2012-01-01

    This state-of-the-art reference contains chapters on all aspects of the characterization of minerals, metals, and materials. The title presents papers from one of the largest yearly gatherings of materials scientists in the world and thoroughly discusses the characterization of minerals, metals, and materials The scope includes current industrial applications and research and developments in the following areas:  Characterization of Ferrous Metals Characterization of Non-Ferrous Materials Characterization of Minerals and Ceramics Character

  17. Hydraulic characterization of " Furcraea andina

    Science.gov (United States)

    Rivera-Velasquez, M. F.; Fallico, C.; Molinari, A.; Santillan, P.; Salazar, M.

    2012-04-01

    The present level of pollution, increasingly involving groundwaters, constitutes a serious risk for environment and human health. Therefore the remediation of saturated and unsaturated soils, removing pollutant materials through innovative and economic bio-remediation techniques is more frequently required. Recent studies on natural fiber development have shown the effectiveness of these fibers for removal of some heavy metals, due to the lignin content in the natural fibers which plays an important role in the adsorption of metal cations (Lee et al., 2004; Troisi et al., 2008; C. Fallico, 2010). In the context of remediation techniques for unsaturated and/or saturated zone, an experimental approach for the hydraulic characterization of the "Furcraea andina" (i.e., Cabuya Blanca) fiber was carried out. This fiber is native to Andean regions and grows easily in wild or cultivated form in the valleys and hillsides of Colombia, Ecuador, and Peru. Fibers of "Furcraea andina" were characterized by experimental tests to determine their hydraulic conductivity or permeability and porosity in order to use this medium for bioremediation of contaminated aquifer exploiting the physical, chemical and microbial capacity of natural fiber in heavy metal adsorption. To evaluate empirically the hydraulic conductivity, laboratory tests were carried out at constant head specifically on the fibers manually extracted. For these tests we used a flow cell (used as permeameter), containing the "Furcraea andina" fibers to be characterized, suitably connected by a tygon pipe to a Marriott's bottle, which had a plastic tube that allow the adjustment of the hydraulic head for different tests to a constant value. By this experiment it was also possible to identify relationships that enable the estimation of permeability as a function of density, i.e. of the compaction degree of the fibers. Our study was carried out for three values of hydraulic head (H), namely 10, 18, and 25 cm and for each

  18. Heparin Characterization: Challenges and Solutions

    Science.gov (United States)

    Jones, Christopher J.; Beni, Szabolcs; Limtiaco, John F. K.; Langeslay, Derek J.; Larive, Cynthia K.

    2011-07-01

    Although heparin is an important and widely prescribed pharmaceutical anticoagulant, its high degree of sequence microheterogeneity and size polydispersity make molecular-level characterization challenging. Unlike nucleic acids and proteins that are biosynthesized through template-driven assembly processes, heparin and the related glycosaminoglycan heparan sulfate are actively remodeled during biosynthesis through a series of enzymatic reactions that lead to variable levels of O- and N-sulfonation and uronic acid epimers. As summarized in this review, heparin sequence information is determined through a bottom-up approach that relies on depolymerization reactions, size- and charge-based separations, and sensitive mass spectrometric and nuclear magnetic resonance experiments to determine the structural identity of component oligosaccharides. The structure-elucidation process, along with its challenges and opportunities for future analytical improvements, is reviewed and illustrated for a heparin-derived hexasaccharide.

  19. Structural characterization of electrodeposited boron

    Indian Academy of Sciences (India)

    Ashish Jain; C Ghosh; T R Ravindran; S Anthonysamy; R Divakar; E Mohandas; G S Gupta

    2013-12-01

    Structural characterization of electrodeposited boron was carried out by using transmission electron microscopy and Raman spectroscopy. Electron diffraction and phase contrast imaging were carried out by using transmission electron microscopy. Phase identification was done based on the analysis of electron diffraction patterns and the power spectrum calculated from the lattice images from thin regions of the sample. Raman spectroscopic examination was carried out to study the nature of bonding and the allotropic form of boron obtained after electrodeposition. The results obtained from transmission electron microscopy showed the presence of nanocrystallites embedded in an amorphous mass of boron. Raman microscopic studies showed that amorphous boron could be converted to its crystalline form at high temperatures.

  20. Synthesis and Characterization of Multithiouracils

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; LIU Hui-Min; ZHANG Wei; ZHANG Wen-Qin

    2003-01-01

    @@ Alkylation of bases group of nucleic acid, thymine and uracil, has attracted great attention. In order to investigate the intermolecular interactions, [1,2] and the photoreactions[3,4] between bases group of nucleic acid, many studies were focused on the synthesis of bisbases in the formation of B-(CH2)n-B (B′) in which trimethylene was commonly used as linker. Thiouracil is an important derivative of nucleic acid bases, and it can interfere with the synthesis of thyroxine, especially in the treatment of hyperthyroidism and angina. However, to our knowledge, the synthesis of bisthiouracils, even trithiouracils, using flexible or rigid linkers has not been reported. Herein, we have synthesized eight thiouracil derivatives by nucleophilic reaction between thiouracil and varied bromides. All the compounds have been characterized by IR, 1H NMR and element analysis.

  1. Characterizing and modeling citation dynamics

    CERN Document Server

    Eom, Young-Ho; 10.1371/journal.pone.0024926

    2011-01-01

    Citation distributions are crucial for the analysis and modeling of the activity of scientists. We investigated bibliometric data of papers published in journals of the American Physical Society, searching for the type of function which best describes the observed citation distributions. We used the goodness of fit with Kolmogorov-Smirnov statistics for three classes of functions: log-normal, simple power law and shifted power law. The shifted power law turns out to be the most reliable hypothesis for all citation networks we derived, which correspond to different time spans. We find that citation dynamics is characterized by bursts, usually occurring within a few years since publication of a paper, and the burst size spans several orders of magnitude. We also investigated the microscopic mechanisms for the evolution of citation networks, by proposing a linear preferential attachment with time dependent initial attractiveness. The model successfully reproduces the empirical citation distributions and accounts...

  2. Technology characterization: liquified natural gas

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-12-01

    A technology characterization for liquefied natural gas (LNG) was made. The scope of work was confined to a literature review of LNG processes including natural gas production, liquefaction, and revaporization. The work was divided into five major categories as follows: (1) status of LNG projects, (2) general process description, (3) environmental aspects, (4) safety, and (5) economics. Each of these categories forms a major heading for this report. In addition, an LNG reference system of 250 million standard cubic feet per day (MMSCFD) is included in the report at Argonne National Laboratory's (Argonne) request. Information concerning this system was derived from other LNG systems in the literature. The report does not include an assessment of the market potential for the product gas or its end use. Published cost estimates in the literature have been identified but the original cost estimates have not been provided. Plant layouts, conceptual designs, and socioeconomic analysis are not provided.

  3. Characterization of Corneal Indentation Hysteresis.

    Science.gov (United States)

    Ko, Match W L; Dongming Wei; Leung, Christopher K S

    2015-01-01

    Corneal indentation is adapted for the design and development of a characterization method for corneal hysteresis behavior - Corneal Indentation Hysteresis (CIH). Fourteen porcine eyes were tested using the corneal indentation method. The CIH measured in enucleated porcine eyes showed indentation rate and intraocular pressure (IOP) dependences. The CIH increased with indentation rate at lower IOP ( 25 mmHg). The CIH was linear proportional to the IOP within an individual eye. The CIH was positively correlated with the IOP, corneal in-plane tensile stress and corneal tangent modulus (E). A new method based on corneal indentation for the measurement of Corneal Indentation Hysteresis in vivo is developed. To our knowledge, this is the first study to introduce the corneal indentation hysteresis and correlate the corneal indentation hysteresis and corneal tangent modulus.

  4. Engineered decoherence: Characterization and suppression

    Science.gov (United States)

    Hegde, Swathi S.; Mahesh, T. S.

    2014-06-01

    Due to omnipresent environmental interferences, quantum coherences inevitably undergo irreversible transformations over certain time scales, thus leading to the loss of encoded information. This process, known as decoherence, has been a major obstacle in realizing efficient quantum information processors. Understanding the mechanism of decoherence is crucial in developing tools to inhibit it. Here we utilize a method proposed by Teklemariam et al. [Phys. Rev. A 67, 062316 (2003), 10.1103/PhysRevA.67.062316] to engineer artificial decoherence in the system qubits by randomly perturbing their surrounding ancilla qubits. Using a two-qubit nuclear magnetic resonance quantum register, we characterize the artificial decoherence by noise spectroscopy and quantum process tomography. Further, we study the efficacy of dynamical decoupling sequences in suppressing the artificial decoherence. Here we describe the experimental results and their comparisons with theoretical simulations.

  5. Entropic characterization of quantum operations

    CERN Document Server

    Roga, Wojciech; Zyczkowski, Karol

    2011-01-01

    We investigate decoherence induced by a quantum channel in terms of minimal output entropy and of map entropy. The latter is the von Neumann entropy of the Jamiolkowski state of the channel. Both quantities admit q-Renyi versions. We prove additivity of the map entropy for all q. For the case q = 2, we show that the depolarizing channel has the smallest map entropy among all channels with a given minimal output Renyi entropy of order two. This allows us to characterize pairs of channels such that the output entropy of their tensor product acting on a maximally entangled input state is larger than the sum of the minimal output entropies of the individual channels. We conjecture that for any channel {\\Phi}1 acting on a finite dimensional system there exists a class of channels {\\Phi}2 sufficiently close to a unitary map such that additivity of minimal output entropy for {\\Psi}1 x {\\Psi}2 holds.

  6. Characterizing stellar and exoplanetary environments

    CERN Document Server

    Khodachenko, Maxim

    2015-01-01

    In this book an international group of specialists discusses studies of exoplanets subjected to extreme stellar radiation and plasma conditions. It is shown that such studies will help us to understand how terrestrial planets and their atmospheres, including the early Venus, Earth and Mars, evolved during the host star’s active early phase. The book presents an analysis of findings from Hubble Space Telescope observations of transiting exoplanets, as well as applications of advanced numerical models for characterizing the upper atmosphere structure and stellar environments of exoplanets. The authors also address detections of atoms and molecules in the atmosphere of “hot Jupiters” by NASA’s Spitzer telescope. The observational and theoretical investigations and discoveries presented are both timely and important in the context of the next generation of space telescopes. 
 The book is divided into four main parts, grouping chapters on exoplanet host star radiation and plasma environments, exoplanet u...

  7. Characterization of NCPA Infrasound Sensors

    Science.gov (United States)

    Hart, D. M.; Jones, K. R.; Sauter, A.

    2011-12-01

    By adding NCPA (National Center for Physical Acoustics) Infrasound sensors to the eastern-half of the Transportable Array, the scientific community has gained another powerful tool for studying natural processes. In an effort to characterize the sensors, including the effect of the wind filter and acoustical porting, researchers at Sandia National Labs (SNL) FACT Site and IRIS PASSCAL have performed a series of tests that resulted in good agreement with the NCPA-provided response (20mV/Pa +-10%, .007Hz high-pass corner frequency). Through independent testing and verification we have gained confidence in the sensor's linearity over the pressure range tested, a measure of power usage, and a measure of the dynamic range the sensors are capable of delivering, indicating the instruments can measure signals well below the Bowman (2005) Acoustic Low Noise Model up to 8Hz. Researchers at the SNL Fact site have the capabilities not only to test the NCPA sensor in an acoustic pressure chamber, but also to test the equivalent of the entire infrasound system used in the TA stations: NCPA sensor, tubing, and wind reduction design (a PVC filter buried in a bag of pumice stone). SNL tests with this fully-ported infrasound system characterize the full system response. We found that the tubing used to port the sensor to the external wind reduction device adds a measurable 15Hz resonance to the response and influences the high-frequency roll-off point. At PASSCAL, we have performed an acceptance test on more than 350 NCPA sensors, and in the process, have collected statistics on their relative gains. The standard deviation of the relative gain for all measured sensors is 5.32%. For 59 repeated tests of the two NCPA sensors used as references, the standard deviation is .15%, which suggests that acceptance testing can be used to constrain the gain of individual NCPA sensors much tighter than the population deviation.

  8. Vanadate-dependent bromoperoxidases from Ascophyllum nodosum in the synthesis of brominated phenols and pyrroles.

    Science.gov (United States)

    Wischang, Diana; Radlow, Madlen; Hartung, Jens

    2013-09-01

    Bromoperoxidases from the brown alga Ascophyllum nodosum, abbreviated as V(Br)PO(AnI) and V(Br)PO(AnII), show 41% sequence homology and differ by a factor of two in the percentage of α-helical secondary structures. Protein monomers organize into homodimers for V(Br)PO(AnI) and hexamers for V(Br)PO(AnII). Bromoperoxidase II binds hydrogen peroxide and bromide by approximately one order of magnitude stronger than V(Br)PO(AnI). In oxidation catalysis, bromoperoxidases I and II turn over hydrogen peroxide and bromide similarly fast, yielding in morpholine-4-ethanesulfonic acid (MES)-buffered aqueous tert-butanol (pH 6.2) molecular bromine as reagent for electrophilic hydrocarbon bromination. Alternative compounds, such as tribromide and hypobromous acid are not sufficiently electrophilic for being directly involved in carbon-bromine bond formation. A decrease in electrophilicity from bromine via hypobromous acid to tribromide correlates in a frontier molecular orbital (FMO) analysis with larger energy gaps between the π-type HOMO of, for example, an alkene and the σ*(Br,X)-type LUMO of the bromination reagent. By using this approach, the reactivity of substrates and selectivity for carbon-bromine bond formation in reactions mediated by vanadate-dependent bromoperoxidases become predictable, as exemplified by the synthesis of bromopyrroles occurring naturally in marine sponges of the genera Agelas, Acanthella, and Axinella. PMID:23881071

  9. Synthesis and TDDFT Investigation of New Maleimide Derivatives Bearing Pyrrole and Indole Ring

    Directory of Open Access Journals (Sweden)

    Yasuhiro Shigemitsu

    2009-01-01

    density-functional theory (TDDFT calculations were systematically performed in order to elucidate their structure-color relationships, using a set of exchange-correlation (XC functionals. The TDDFT computational scheme employing PCM-TDDFT/6-31+G(d,p//DFT/6-311G(d,p level of theory gave qualitatively satisfactory results in their max predictions.

  10. Estimate Secondary Oil Migration Distance Using Pyrrolic Nitrogen Compounds in Petroleum

    Institute of Scientific and Technical Information of China (English)

    Li Maowen

    1997-01-01

    @@ Secondary oil migration represents one of the most important, yet least understood, geological processes responsible for the petroleum accumulation in a sedimentary basin. During secondary migration, petroleum moves updip as high-petroleum saturation rivers driven largely by buoyancy over migration distances ranging from millimeters to hundreds of kilometers. Mass balance calculations indicate that the oil-saturated portions of the carrier bed are in the order of 1%~10% of the carrier bed volume. In most cases, however, the actual dimensions of migration conduits cannot be defined by direct observation,thus preventing useful volumetric estimates of oil charges to structures, or prospect-scale deterministic modeling of secondary migration for predictive purpose.

  11. 5-(4-Methylphenylsulfonyl-1,3-dithiolo[4,5-c]pyrrole-2-thione

    Directory of Open Access Journals (Sweden)

    Ning-Juan Zheng

    2012-04-01

    Full Text Available The asymmetric unit of the title compound, C12H9NO2S4, contains one half-molecule with the N, two S amd four C atoms lying on a mirror plane. The molecule exhibits a V-shaped conformation, with a dihedral angle of 87.00 (7° between the benzene and dithiolopyrrole rings. The methyl group was treated as rotationally disordered between two orientations in a 1:1 ratio. In the crystal, weak C—H...O hydrogen bonds link the molecules into chains in [010].

  12. 1,5-Bis(2,5-dimethyl-1H-pyrrol-1-ylnaphthalene

    Directory of Open Access Journals (Sweden)

    A. C. Santos

    2009-11-01

    Full Text Available In the title compound, C22H22N2, the asymmetric unit contains one half-molecule. A crystallographic inversion centre is located at the mid-point of the bond common to both rings, in the central naphthalene unit. Quantum-mechanical ab initio calculations on the isolated molecule showed that the minimum energy configuration occurs when the naphthalene ring system and the pyrrolyl groups deviate only slightly from perpendicularity. In the crystal, due to the effects of crystal packing, the molecule deviates by approximately 4° from the a priori expected ideal value of 90° [C—C—N—C torsion angle = 86.11 (15°].

  13. The Influence of Preparation Conditions on the Electrical Conductivity of Poly N-Methyl-pyrrole Films

    DEFF Research Database (Denmark)

    Vidanapathirana, K.; Careem, M.A.; Skaarup, Steen;

    1999-01-01

    on the electrical conductivity has been investigated. The conductivity was measured by the in situ method using a specially prepared two-band microelectrode. The current density used during the polymerization has a considerable influence on the conductivity, as earlier observed for polypyrrole in non......-aqueous electrolytes. The conductivity changes with the size of the anion and the concentration of the electrolyte as well as on the temperature at which the polymerization was carried out. Polymer films formed at relatively higher temperatures had lower conductivities and were not able to insert as many counterions...

  14. Biosynthesis, asymmetric synthesis, and pharmacology, including cellular targets, of the pyrrole-2-aminoimidazole marine alkaloids

    Digital Repository Service at National Institute of Oceanography (India)

    Al-Mourabit, A.; Zancanella, M.A.; Tilvi, S.; Romo, D.

    biosynthetic intermediates e.g. clathrodin (5) or oroidin (6). While biosynthetic details are completely lacking, biomechanistic analysis of isolated P-2-AIs and successful synthetic strategies premised on speculative biosynthetic pathways have provided some... indirect evidence regarding biosynthetic feasibility. From the standpoint that inherent reactivity of biosynthetic intermediates may offer clues about actual biosynthetic pathways leading to various complex P-2-AIs, isolation of an increasing number...

  15. Site-selective nanoscale-polymerization of pyrrole on gold nanoparticles via plasmon induced charge separation.

    Science.gov (United States)

    Takahashi, Y; Furukawa, Y; Ishida, T; Yamada, S

    2016-04-28

    We proposed a nanoscale oxidative polymerization method which enables site-selective deposition on the surface of gold nanoparticles (AuNPs) combined with TiO2 by using plasmon induced charge separation (PICS) under visible-to-near infrared (IR) light irradiation. The method also revealed that the anodic site of PICS was located at the surface of AuNPs.

  16. Synthesis, characterization and enhanced photoconductivity from a mesoporous titania on dye doping.

    Science.gov (United States)

    Pal, Nabanita; Paul, Manidipa; Bera, Ashoke; Basak, Durga; Bhaumik, Asim

    2010-07-26

    New wormhole-like mesoporous TiO(2) material has been synthesized through a convenient sol-gel method in the presence of a Schiff base secondary amine hexadecyl-2-pyrrole-methylamine (HPMA) containing chelating donor sites as template or structure directing agent (SDA). SDA molecules can be easily removed from the composite to generate mesoporosity and upon removal of the SDA molecule, this mesoporous TiO(2) material showed very high surface area (480+/-10 m(2)/g) with an average pore diameter of 2.57+/-0.05 nm. When Rose Bengal dye is entrapped inside the nanopores of this material, it showed a drastic enhancement (ca. 40-folds) in the photoconductivity vis-à-vis mesoporous TiO(2) alone under white light illumination. PMID:20638505

  17. Synthesis and characterization of conductive core-shell polyacrylonitrile-polypyrrole nanofibers.

    Science.gov (United States)

    Jun, Tae-Sun; Nguyen, Tuan-Anh; Jung, Yongju; Kim, Yong Shin

    2012-07-01

    Nonwoven polyacrylonitrile-polypyrrole (PAN-PPy) core-shell nanofiber mats were prepared through the growth of PPy layers on electrospun PAN nanofibers via a two-step vapor-phase polymerization, i.e., the wet-coating of ferric tosylate (FeTos) oxidants on PAN nanofibers followed by exposure to pyrrole monomers in the gas phase. Under the conditions ([FeTos] = 10 wt%, reaction time = 15 min, temperature = 15 degrees C), the PPy polymerization procedure led to both a uniform coating over the PAN surface with an average thickness of 18 nm and cross-linkages among the nanofibers without a noticeable change in the highly porous nanofibrous structures. The oxidant concentration and polymerization time were found to be key parameters for achieving a good nanostructured core-shell fiber mat. FT-IR, XPS, XRD and conductivity measurements confirmed the synthesis of Tos-doped PPy with some degree of crystallinity and a high conductivity. PMID:22966690

  18. Characterization of Prototype LSST CCDs

    Energy Technology Data Exchange (ETDEWEB)

    OCONNOR,P.; FRANK, J.; GEARY, J.C.; GILMORE, D.K.; KOTOV, I.; RADEKA, V.; TAKACS, P.; TYSON, J.A.

    2008-06-23

    The ambitious science goals of the Large Synoptic Survey Telescope (LSST) will be achieved in part by a wide-field imager that will achieve a new level of performance in terms of area, speed, and sensitivity. The instrument performance is dominated by the focal plane sensors, which are now in development. These new-generation sensors will make use of advanced semiconductor technology and will be complemented by a highly integrated electronics package located inside the cryostat. A test laboratory has been set up at Brookhaven National Laboratory (BNL) to characterize prototype sensors and to develop test and assembly techniques for eventual integration of production sensors and electronics into modules that will form the final focal plane. As described in [1], the key requirements for LSST sensors are wideband quantum efficiency (QE) extending beyond lpm in the red, control of point spread function (PSF), and fast readout using multiple amplifiers per chip operated in parallel. In addition, LSST's fast optical system (f71.25) places severe constraints on focal plane flatness. At the chip level this involves packaging techniques to minimize warpage of the silicon die, and at the mosaic level careful assembly and metrology to achieve a high coplanarity of the sensor tiles. In view of the long lead time to develop the needed sensor technology, LSST undertook a study program with several vendors to fabricate and test devices which address the most critical performance features [2]. The remainder of this paper presents key results of this study program. Section 2 summarizes the sensor requirements and the results of design optimization studies, and Section 3 presents the sensor development plan. In Section 4 we describe the test bench at BNL. Section 5 reports measurement results obtained to date oh devices fabricated by several vendors. Section 6 presents a summary of the paper and an outlook for the future work. We present characterization methods and results on

  19. 新型溴代长波长BODIPY类荧光染料的合成及表征%Synthesis,characterization and spectral properties of several novel long-wavelength Br-substituted BODIPY dyes

    Institute of Scientific and Technical Information of China (English)

    华仕能; 崔爱军; 何明阳; 陈广峰; 陈群

    2009-01-01

    A long-wavelength BODIPY dye substituted by pyrrolyl groups was synthesized from pyrrole and acetyl chloride in one step,and then the monobromo- and dibromo-derivatives were also prepared.The structures of all these dyes were characterized by MS and ~1HNMR.The absorption and emission spectra of the dyes were measured,and the spectral solvent effect in different polarity solvents was researched. Furthermore, the heavy atom effect on bromo-dyes was investigated. The results of our work were listed as follows. With the enhancement of solvent polarity, blue shift was detected on the absorption wavelength of these dyes, and the extinction coefficients increased with little change in the emission wavelength, while the fluorescence quantum yield decreased grad-ually. The above-mentioned phenomena represented the apparent solvent effect of the spectra. In the same solvent, with increasing bromine atoms, the red shift was detected on emission wavelength of the dyes, and the extinction coefficients increased with little change in the absorption wavelength, while the fluorescence quan-tum yield decreased gradually. These data indicated the heavy atom effect of the spectra.%通过吡咯和乙酰氯经一步法合成了含吡咯取代基的长波长BODIPY染料,溴化后得到一溴和二溴染料,染料通过质谱、二维核磁等手段进行了结构表征.测试了这些染料的吸收光谱和发射光谱,研究了不同极性的溶剂对染料光谱性能的溶剂化效应以及Br原子对染料光谱的重原子效应.结果表明:随着溶剂极性的增大所合成的染料吸收波长均发生了蓝移,发射波长变化不大,摩尔消光系数逐渐增大,荧光量子产率逐渐减小,表现出明显的溶剂化效应;在同一溶剂中,随着染料结构中Br原子取代基数目的增加,发射波长发生红移,吸收波长变化不大,摩尔消光系数逐渐增大,荧光量子产率逐渐减小,表现出明显的重原子效应.

  20. High-G Thermal Characterization Centrifuge

    Data.gov (United States)

    Federal Laboratory Consortium — High-G testing of thermal components enables improved understanding of operating behavior under military-relevant environments. The High-G Thermal Characterization...

  1. NCL Objective #5 - Nanotechnology Characterization Lab (NCL)

    Science.gov (United States)

    Nanotechnology Characterization Lab (NCL) Objective #5: Engage and Facilitate Academic and Industrial-based Knowledge Sharing of Nanomaterial Performance Data and Behavior Resulting from Pre-Clinical Testing.

  2. Frontiers of Exoplanet Atmosphere Characterization

    Science.gov (United States)

    Kreidberg, Laura

    2016-01-01

    Exoplanet atmosphere characterization has the potential to reveal the origins, nature, and even habitability of distant worlds. In this dissertation talk, I will present work that is a step toward realizing that potential for a diverse group of four extrasolar planets. I will discuss the results of intensive observational campaigns with the Hubble and Spitzer Space Telescopes to study the atmospheres of the super-Earth GJ 1214b and the hot Jupiters WASP-43b, WASP-12b, and WASP-103b. For GJ 1214b, I measured an unprecedentedly precise near-infrared transmission spectrum that definitively reveals the presence of clouds in the planet's atmosphere. For WASP-43b and WASP-12b, I also obtained very precise spectra. These exhibit water features at high confidence (>7 sigma). The retrieved water abundance for WASP-43b extends the well-known Solar System trend of decreasing atmospheric metallicity with increasing planet mass. The detection of water for WASP-12b marks the first spectroscopic identification of a molecule in the planet's atmosphere and implies that it has solar composition, ruling out carbon-to-oxygen ratios greater than unity. For WASP-103b, I will present preliminary results from the new technique of phase-resolved spectroscopy that constrain the planet's temperature structure, dynamics, and energy budget. Taken together, these results provide a foundation for comparative planetology beyond the Solar System and the investigation of Earth-like, potentially habitable planets with future observing facilities.

  3. Characterization of superconducting multilayers samples

    CERN Document Server

    Antoine, C Z; Berry, S; Bouat, S; Jacquot, J F; Villegier, J C; Lamura, G; Gurevich, A

    2009-01-01

    Best RF bulk niobium accelerating cavities have nearly reached their ultimate limits at rf equatorial magnetic field H  200 mT close to the thermodynamic critical field Hc. In 2006 Gurevich proposed to use nanoscale layers of superconducting materials with high values of Hc > HcNb for magnetic shielding of bulk niobium to increase the breakdown magnetic field inside SC RF cavities [1]. Depositing good quality layers inside a whole cavity is rather difficult but we have sputtered high quality samples by applying the technique used for the preparation of superconducting electronics circuits and characterized these samples by X-ray reflectivity, dc resistivity (PPMS) and dc magnetization (SQUID). Dc magnetization curves of a 250 nm thick Nb film have been measured, with and without a magnetron sputtered coating of a single or multiple stack of 15 nm MgO and 25 nm NbN layers. The Nb samples with/without the coating clearly exhibit different behaviors. Because SQUID measurements are influenced by edge an...

  4. Characterizing and modeling citation dynamics.

    Directory of Open Access Journals (Sweden)

    Young-Ho Eom

    Full Text Available Citation distributions are crucial for the analysis and modeling of the activity of scientists. We investigated bibliometric data of papers published in journals of the American Physical Society, searching for the type of function which best describes the observed citation distributions. We used the goodness of fit with Kolmogorov-Smirnov statistics for three classes of functions: log-normal, simple power law and shifted power law. The shifted power law turns out to be the most reliable hypothesis for all citation networks we derived, which correspond to different time spans. We find that citation dynamics is characterized by bursts, usually occurring within a few years since publication of a paper, and the burst size spans several orders of magnitude. We also investigated the microscopic mechanisms for the evolution of citation networks, by proposing a linear preferential attachment with time dependent initial attractiveness. The model successfully reproduces the empirical citation distributions and accounts for the presence of citation bursts as well.

  5. Physicochemical characterization of Gozitan Honey

    Directory of Open Access Journals (Sweden)

    Everaldo Attard

    2013-10-01

    Full Text Available Honey quality is clearly defined in the EU Directive 2001/110/EC, and by Codex Alimentarius (Codex Stan 12-1981 and the International Honey Commission (IHC, 2002. Our investigation aimed to characterize the physicochemical properties of honey produced on a small island, Gozo which is situated near Malta.  Ten randomly collected honey samples were analysed for moisture content, pH, free acidity, water insoluble content, hydroxymethylfurfural (HMF content and total phenolic compounds.  Moisture content, pH, free acidity, water insoluble content, and HMF content were within the range specified in standards but the electrical conductivity was generally higher than 0.800 mS cm-1. This may be the result of the relatively high atmospheric and soil salinity on this small island. All the samples analysed were within the 40 mg kg-1 HMF limit, which is an indicator of honey quality. The total phenolic compounds, which represent some of the constituents derived from the nectar and pollen obtained during foraging, ranged between 236.555 and 294.209 GAE kg-1 honey. Principal Component Analysis showed the properties of polyfloral honey samples obtained from the southern part of the island to be different from those obtained from the northern part.

  6. Geomechanical Characterization of Marcellus Shale

    Science.gov (United States)

    Villamor Lora, Rafael; Ghazanfari, Ehsan; Asanza Izquierdo, Enrique

    2016-09-01

    Understanding the reservoir conditions and material properties that govern the geomechanical behavior of shale formations under in situ conditions is of vital importance for many geomechanical applications. The development of new numerical codes and advanced multi-physical (thermo-hydro-chemo-mechanical) constitutive models has led to an increasing demand for fundamental material property data. Previous studies have shown that deformational rock properties are not single-value, well-defined, linear parameters. This paper reports on an experimental program that explores geomechanical properties of Marcellus Shale through a series of isotropic compression (i.e. σ 1 = σ 2 = σ 3) and triaxial (i.e. σ 1 > σ 2 = σ 3) experiments. Deformational and failure response of these rocks, as well as anisotropy evolution, were studied under different stress and temperature conditions using single- and multi-stage triaxial tests. Laboratory results revealed significant nonlinear and pressure-dependent mechanical response as a consequence of the rock fabric and the occurrence of microcracks in these shales. Moreover, multi-stage triaxial tests proved to be useful tools for obtaining failure envelopes using a single specimen. Furthermore, the anisotropic nature of Marcellus Shale was successfully characterized using a three-parameter coupled model.

  7. Geophysical characterization of subsurface barriers

    Energy Technology Data Exchange (ETDEWEB)

    Borns, D.J.

    1995-08-01

    An option for controlling contaminant migration from plumes and buried waste sites is to construct a subsurface barrier of a low-permeability material. The successful application of subsurface barriers requires processes to verify the emplacement and effectiveness of barrier and to monitor the performance of a barrier after emplacement. Non destructive and remote sensing techniques, such as geophysical methods, are possible technologies to address these needs. The changes in mechanical, hydrologic and chemical properties associated with the emplacement of an engineered barrier will affect geophysical properties such a seismic velocity, electrical conductivity, and dielectric constant. Also, the barrier, once emplaced and interacting with the in situ geologic system, may affect the paths along which electrical current flows in the subsurface. These changes in properties and processes facilitate the detection and monitoring of the barrier. The approaches to characterizing and monitoring engineered barriers can be divided between (1) methods that directly image the barrier using the contrasts in physical properties between the barrier and the host soil or rock and (2) methods that reflect flow processes around or through the barrier. For example, seismic methods that delineate the changes in density and stiffness associated with the barrier represents a direct imaging method. Electrical self potential methods and flow probes based on heat flow methods represent techniques that can delineate the flow path or flow processes around and through a barrier.

  8. Mechanical Characterization of Mancos Shale

    Science.gov (United States)

    Broome, S.; Ingraham, M. D.; Dewers, T. A.

    2015-12-01

    A series of tests on Mancos shale have been undertaken to determine the failure surface and to characterize anisotropy. This work supports additional studies which are being performed on the same block of shale; fracture toughness, permeability, and chemical analysis. Mechanical tests are being conducted after specimens were conditioned for at least two weeks at 70% constant relative humidity conditions. Specimens are tested under drained conditions, with the constant relative humidity condition maintained on the downstream side of the specimen. The upstream is sealed. Anisotropy is determined through testing specimens that have been cored parallel and perpendicular to the bedding plane. Preliminary results show that when loaded parallel to bedding the shale is roughly 50% weaker. Test are run under constant mean stress conditions when possible (excepting indirect tension, unconfined compression, and hydrostatic). Tests are run in hydrostatic compaction to the desired mean stress, then differential stress is applied axially in displacement control to failure. The constant mean stress condition is maintained by decreasing the confining pressure by half of the increase in the axial stress. Results will be compared to typical failure criteria to investigate the effectiveness of capturing the behavior of the shale with traditional failure theory. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. SAND2015-6107 A.

  9. Geophysical characterization of subsurface barriers

    International Nuclear Information System (INIS)

    An option for controlling contaminant migration from plumes and buried waste sites is to construct a subsurface barrier of a low-permeability material. The successful application of subsurface barriers requires processes to verify the emplacement and effectiveness of barrier and to monitor the performance of a barrier after emplacement. Non destructive and remote sensing techniques, such as geophysical methods, are possible technologies to address these needs. The changes in mechanical, hydrologic and chemical properties associated with the emplacement of an engineered barrier will affect geophysical properties such a seismic velocity, electrical conductivity, and dielectric constant. Also, the barrier, once emplaced and interacting with the in situ geologic system, may affect the paths along which electrical current flows in the subsurface. These changes in properties and processes facilitate the detection and monitoring of the barrier. The approaches to characterizing and monitoring engineered barriers can be divided between (1) methods that directly image the barrier using the contrasts in physical properties between the barrier and the host soil or rock and (2) methods that reflect flow processes around or through the barrier. For example, seismic methods that delineate the changes in density and stiffness associated with the barrier represents a direct imaging method. Electrical self potential methods and flow probes based on heat flow methods represent techniques that can delineate the flow path or flow processes around and through a barrier

  10. Infrared pyrometry for waste characterization

    International Nuclear Information System (INIS)

    The objective of this research is the development of two methodologies by which heat sources contained in underground storage tanks (USTs) can be remotely characterized. A problem statement is established based upon the restrictions of UST robotic capabilities and basic infrared (IR) pyrometer operation. The first analysis is designed to provide real time information to a robot operator about the UST interior. The other analysis is designed to calculate an estimated temperature distribution using a least-squares solution after a data survey. A mock UST designed by Sandia National Laboratories and New Mexico State University was built to provide a test bed for data collection. Two data sets are graphically presented to show the positions of known heat sources and their thermal responses. The results of the two analyses on the data sets are graphically presented to illustrate the correlation between known heat sources and estimated thermal targets. In conclusion, the estimated temperature distribution provides a higher resolution image of the UST surface, as compared to the measured temperature distribution, such that individual heat sources may be located

  11. Characterizing humans on Riemannian manifolds.

    Science.gov (United States)

    Tosato, Diego; Spera, Mauro; Cristani, Marco; Murino, Vittorio

    2013-08-01

    In surveillance applications, head and body orientation of people is of primary importance for assessing many behavioral traits. Unfortunately, in this context people are often encoded by a few, noisy pixels so that their characterization is difficult. We face this issue, proposing a computational framework which is based on an expressive descriptor, the covariance of features. Covariances have been employed for pedestrian detection purposes, actually a binary classification problem on Riemannian manifolds. In this paper, we show how to extend to the multiclassification case, presenting a novel descriptor, named weighted array of covariances, especially suited for dealing with tiny image representations. The extension requires a novel differential geometry approach in which covariances are projected on a unique tangent space where standard machine learning techniques can be applied. In particular, we adopt the Campbell-Baker-Hausdorff expansion as a means to approximate on the tangent space the genuine (geodesic) distances on the manifold in a very efficient way. We test our methodology on multiple benchmark datasets, and also propose new testing sets, getting convincing results in all the cases.

  12. Multilayer Piezoelectric Stack Actuator Characterization

    Science.gov (United States)

    Sherrit, Stewart; Jones, Christopher M.; Aldrich, Jack B.; Blodget, Chad; Bao, Xioaqi; Badescu, Mircea; Bar-Cohen, Yoseph

    2008-01-01

    Future NASA missions are increasingly seeking to use actuators for precision positioning to accuracies of the order of fractions of a nanometer. For this purpose, multilayer piezoelectric stacks are being considered as actuators for driving these precision mechanisms. In this study, sets of commercial PZT stacks were tested in various AC and DC conditions at both nominal and extreme temperatures and voltages. AC signal testing included impedance, capacitance and dielectric loss factor of each actuator as a function of the small-signal driving sinusoidal frequency, and the ambient temperature. DC signal testing includes leakage current and displacement as a function of the applied DC voltage. The applied DC voltage was increased to over eight times the manufacturers' specifications to investigate the correlation between leakage current and breakdown voltage. Resonance characterization as a function of temperature was done over a temperature range of -180C to +200C which generally exceeded the manufacturers' specifications. In order to study the lifetime performance of these stacks, five actuators from one manufacturer were driven by a 60volt, 2 kHz sine-wave for ten billion cycles. The tests were performed using a Lab-View controlled automated data acquisition system that monitored the waveform of the stack electrical current and voltage. The measurements included the displacement, impedance, capacitance and leakage current and the analysis of the experimental results will be presented.

  13. Laboratory characterization of rock joints

    International Nuclear Information System (INIS)

    A laboratory characterization of the Apache Leap tuff joints under cyclic pseudostatic and dynamic loads has been undertaken to obtain a better understanding of dynamic joint shear behavior and to generate a complete data set that can be used for validation of existing rock-joint models. Study has indicated that available methods for determining joint roughness coefficient (JRC) significantly underestimate the roughness coefficient of the Apache Leap tuff joints, that will lead to an underestimation of the joint shear strength. The results of the direct shear tests have indicated that both under cyclic pseudostatic and dynamic loadings the joint resistance upon reverse shearing is smaller than that of forward shearing and the joint dilation resulting from forward shearing recovers during reverse shearing. Within the range of variation of shearing velocity used in these tests, the shearing velocity effect on rock-joint behavior seems to be minor, and no noticeable effect on the peak joint shear strength and the joint shear strength for the reverse shearing is observed

  14. Parametric characterizations in superparamagnetic latex

    Indian Academy of Sciences (India)

    Seda Beyaz; Hakan Kockar; Taner Tanrisever

    2014-05-01

    The effect of synthesis parameters on the production of superparamagnetic latex, which are magnetite nanoparticles covered with a poly(methyl methacrylate) layer, were studied. The synthesis method was based on the developed route of emulsifier-free emulsion polymerization. Under this study, effects of the monomer and initiator concentrations, the amount of magnetic sol, the stirring rate and the adding rate of the magnetic sol on the properties of synthesized latexes were investigated. The characterizations were performed by a high resolution transmission electron microscopy, a dynamic light scattering, a vibrating sample magnetometer and a gel permeation chromatography. The results showed that the monomer concentration was found to be the most effective parameter on latex stability. As the initiator amount and the stirring rate increased, saturation magnetization and average molecular weight decreased due to the reactions occurring between surfaces of magnetite nanoparticles and initiator fragments. On increasing amount of magnetic sol, the saturation magnetization and polymer molecular weight increased but the size of nanospheres was unchanged because of the ions in magnetic sol. It was seen that the desired size and magnetic properties of the latex could be obtained since the parameters were found to have substantial impact on their properties.

  15. Characterization of vanadium flow battery

    Energy Technology Data Exchange (ETDEWEB)

    Bindner, H.; Ekman, C.; Gehrke, O.; Isleifsson, F.

    2010-10-15

    This report summarizes the work done at Risoe DTU testing a vanadium flow battery as part of the project 'Characterisation of Vanadium Batteries' (ForskEl project 6555) with the partners PA Energy A/S and OI Electric A/S under the Danish PSO energy research program. A 15kW/120kWh vanadium battery has been installed as part of the distributed energy systems experimental facility, SYSLAB, at Risoe DTU. A test programme has been carried out to get hands-on experience with the technology, to characterize the battery from a power system point of view and to assess it with respect to integration of wind energy in the Danish power system. The battery has been in operation for 18 months. During time of operation the battery has not shown signs of degradation of performance. It has a round-trip efficiency at full load of approximately 60% (depending on temperature and SOC). The sources of the losses are power conversion in cell stacks/electrolyte, power converter, and auxiliary power consumption from pumps and controller. The response time for the battery is limited at 20kW/s by the ramp rate of the power converter. The battery can thus provide power and frequency support for the power system. Vanadium battery is a potential technology for storage based services to the power system provided investment and O and M cost are low enough and long term operation is documented. (Author)

  16. Characterizing Internet Worm Infection Structure

    CERN Document Server

    Wang, Qian; Chen, Chao

    2010-01-01

    Internet worm infection continues to be one of top security threats. Moreover, worm infection has been widely used by botnets to recruit new bots and construct P2P-based botnets. In this work, we attempt to characterize the network structure of Internet worm infection and shed light on the micro-level information of "who infects whom." Our work quantifies the infection ability of individual hosts and reveals the key characteristics of the underlying topologies formed by worm infection, i.e., the number of children and the generation of the Internet worm infection family tree. Specifically, we first analyze the infection tree of a wide class of worms, for which a new victim is compromised by each existing infected host with equal probability. We find that the number of children has asymptotically a geometric distribution with parameter 0.5. We also discover that the generation follows closely a Poisson distribution and the average path length of the worm infection family tree increases approximately logarithmi...

  17. Laboratory characterization of rock joints

    Energy Technology Data Exchange (ETDEWEB)

    Hsiung, S.M.; Kana, D.D.; Ahola, M.P.; Chowdhury, A.H.; Ghosh, A. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

    1994-05-01

    A laboratory characterization of the Apache Leap tuff joints under cyclic pseudostatic and dynamic loads has been undertaken to obtain a better understanding of dynamic joint shear behavior and to generate a complete data set that can be used for validation of existing rock-joint models. Study has indicated that available methods for determining joint roughness coefficient (JRC) significantly underestimate the roughness coefficient of the Apache Leap tuff joints, that will lead to an underestimation of the joint shear strength. The results of the direct shear tests have indicated that both under cyclic pseudostatic and dynamic loadings the joint resistance upon reverse shearing is smaller than that of forward shearing and the joint dilation resulting from forward shearing recovers during reverse shearing. Within the range of variation of shearing velocity used in these tests, the shearing velocity effect on rock-joint behavior seems to be minor, and no noticeable effect on the peak joint shear strength and the joint shear strength for the reverse shearing is observed.

  18. Fractal Characterization of Hyperspectral Imagery

    Science.gov (United States)

    Qiu, Hon-Iie; Lam, Nina Siu-Ngan; Quattrochi, Dale A.; Gamon, John A.

    1999-01-01

    Two Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) hyperspectral images selected from the Los Angeles area, one representing urban and the other, rural, were used to examine their spatial complexity across their entire spectrum of the remote sensing data. Using the ICAMS (Image Characterization And Modeling System) software, we computed the fractal dimension values via the isarithm and triangular prism methods for all 224 bands in the two AVIRIS scenes. The resultant fractal dimensions reflect changes in image complexity across the spectral range of the hyperspectral images. Both the isarithm and triangular prism methods detect unusually high D values on the spectral bands that fall within the atmospheric absorption and scattering zones where signature to noise ratios are low. Fractal dimensions for the urban area resulted in higher values than for the rural landscape, and the differences between the resulting D values are more distinct in the visible bands. The triangular prism method is sensitive to a few random speckles in the images, leading to a lower dimensionality. On the contrary, the isarithm method will ignore the speckles and focus on the major variation dominating the surface, thus resulting in a higher dimension. It is seen where the fractal curves plotted for the entire bandwidth range of the hyperspectral images could be used to distinguish landscape types as well as for screening noisy bands.

  19. Chemical characterization of CVD tungsten

    International Nuclear Information System (INIS)

    Characterization of tungsten films that have been deposited under ''selective'' conditions is presented. SEM and TEM studies indicate good conformal coverage and minimum encroachment. Cross section TEM results may indicate that some ''damage'' occurs at hole corners. Auger and SIMS depth profiles reveal very clean films. SIMS however does reveal that fluorine is a contaminant. Tungsten films were deposited at about 30A/min at 3000C with a 30/1 H/sub 2//WF/sub 6/ flow ration at 0.3 Torr. These films were selective up to film thicknesses of about 2000A. Mass spectral analysis of 99.8% WF/sub 6/ indicated no oxyfluorides and only a trace of methyl fluorosilanes that may have been an artifact of the gas sampling technique via contamination with silicone grease or lubricant. The sheet resistance of films became constant at about 8μ Ω-cm for film thicknesses (measured by profilometer after tungsten etch) greater than 4000A and increased up to about 20μ Ω-cm for very thin films (less than 500A). Auger depth profiling indicated that a thin oxide layer at the tungsten silicon interface corresponded to films having good adhesion as determined by a scribed tape pull test; where as a film deposited on a freshly HF cleaned surface with high carbon level had poor adhesion. Auger analysis indicated clean tungsten films with no evidence of fluorine. However, SIMS analysis indicated measurable levels of fluorine throughout the tungsten film and fluorine may be a significant contaminant as at higher temperatures it was found to have migrated to all interface areas as shown in SIMS study of annealed and unannealed W Six. The importance of fluorine impurities has not been correlated with any electrical properties

  20. Multimodality instrument for tissue characterization

    Science.gov (United States)

    Mah, Robert W. (Inventor); Andrews, Russell J. (Inventor)

    2004-01-01

    A system with multimodality instrument for tissue identification includes a computer-controlled motor driven heuristic probe with a multisensory tip. For neurosurgical applications, the instrument is mounted on a stereotactic frame for the probe to penetrate the brain in a precisely controlled fashion. The resistance of the brain tissue being penetrated is continually monitored by a miniaturized strain gauge attached to the probe tip. Other modality sensors may be mounted near the probe tip to provide real-time tissue characterizations and the ability to detect the proximity of blood vessels, thus eliminating errors normally associated with registration of pre-operative scans, tissue swelling, elastic tissue deformation, human judgement, etc., and rendering surgical procedures safer, more accurate, and efficient. A neural network program adaptively learns the information on resistance and other characteristic features of normal brain tissue during the surgery and provides near real-time modeling. A fuzzy logic interface to the neural network program incorporates expert medical knowledge in the learning process. Identification of abnormal brain tissue is determined by the detection of change and comparison with previously learned models of abnormal brain tissues. The operation of the instrument is controlled through a user friendly graphical interface. Patient data is presented in a 3D stereographics display. Acoustic feedback of selected information may optionally be provided. Upon detection of the close proximity to blood vessels or abnormal brain tissue, the computer-controlled motor immediately stops probe penetration. The use of this system will make surgical procedures safer, more accurate, and more efficient. Other applications of this system include the detection, prognosis and treatment of breast cancer, prostate cancer, spinal diseases, and use in general exploratory surgery.

  1. Chemical characterization of marajoara ceramics

    International Nuclear Information System (INIS)

    In this study the elemental concentration of Ce, Co, Cr, Cs, Eu, Fe, Hf, K, La, Lu, Na, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn were determined by instrumental neutron activation analysis (INAA) in 204 fragments of Marajoara archaeological ceramics, of which 156 were provided by the Archaeology and Ethnology Museum of Sao Paulo University (MAE) and 48 were provided by Dr. Denise Pahl Schaan, Marajo Museum curator. Also, 9 contemporary ceramics produced and marketed at Marajo Island were analyzed. Electron paramagnetic resonance (EPR) analyses were performed in 8 archaeological samples and 1 contemporary sample in order to identify the burning temperature of the samples. X-ray diffraction (XRD) analyses were performed in 13 archaeological samples and 2 contemporary samples for the investigation of their mineralogical composition. Mahalanobis distance was used for the study of outlier while modified filter was used for the study of the temper added to the ceramic paste. Result interpretation was performed using cluster analysis, principal components analysis and discriminant analysis. Procrustes analysis was used for variable selection and it showed that the Ce, Fe, Eu, Hf, K and Th variables are adequate for the characterization of the analyzed samples. The comparative study among the archaeological and contemporary ceramics showed the arrangement of two well-defined and close groups for the archaeological samples and a third, distant group for the contemporary ones. This result indicates that the archaeological and contemporary ceramics differ in their composition. EPR and XRD analysis were inconclusive for the differentiation of archaeological and contemporary ceramics. (author)

  2. Characterization of polymorphic ampicillin forms.

    Science.gov (United States)

    Baraldi, C; Tinti, A; Ottani, S; Gamberini, M C

    2014-11-01

    In this work polymorphs of α-aminobenzylpenicillin (ampicillin), a β-lactamic antibiotic, were prepared and investigated by several experimental and theoretical methods. Amorphous monohydrate and three crystalline forms, the trihydrate, the crystal form I and the crystal form II, were investigated by FT-IR and micro-Raman. Also data obtained by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray powder diffraction (XRPD) and hot-stage Raman spectroscopy are reported. Finally, quantum mechanical calculations were performed by density functional theory (DFT) to assist the assignment of spectroscopic experimental bands. For the first time, the ampicillin molecule in its zwitterionic form was studied at the B3LYP/aug-cc-pVDZ level and the corresponding theoretical vibrational spectra were computed. In fact, ampicillin in the crystal is in zwitterionic form and concentrations of this same form are quite relevant in solutions at physiological pH. Experimental and theoretical results allowed identification of specific features for polymorph characterization. Bands typical of the different polymorphs are identified both in IR and Raman spectra: in particular in the NH stretching region (IR), in the amide I+δNH region (both techniques), in the 1520-1490cm(-1) region (IR), in the 1320-1300cm(-1) and 1280-1220cm(-1) (IR), in the 1200-1170cm(-1) (Raman), in the amide V region (IR), and, finally, in the 715-640cm(-1) and 220-200cm(-1) (Raman). Interconversion among different polymorphs was investigated by hot-stage Raman spectroscopy and thermal analysis, clarifying the complex pattern of transformations undergone as a function of temperature and heating rate. In particular, DSC scans show how the trihydrate crystals transform into anhydrous forms on heating. Finally, stability tests demonstrated, after a two years period, that no transformation or degradation of the polymorphs occurred.

  3. Characterization of ashes from biofuels

    Energy Technology Data Exchange (ETDEWEB)

    Frandsen, F.J.; Hansen, L.A. [Technical Univ. of Denmark. Dept. of Chemical Engineering (Denmark); Soerensen, H.S. [Geological Survey of Denmark and Greenland (Denmark); Hjuler, K. [dk-TEKNIK. Energy and Environment (Denmark)

    1998-02-01

    One motivation for initiating the present project was that the international standard method of estimating the deposit propensity of solid fuels, of which a number of variants exist (e.g. ISO, ASTM, SD, DIN), has shown to be unsuitable for biomass ashes. This goal was addressed by the development of two new methods for the detection of ash fusibility behaviour based on Simultaneous Thermal Analysis (STA) and High Temperature Light Microscopy (HTLM), respectively. The methods were developed specifically for ashes from biofuels, but are suitable for coal ashes as well. They have been tested using simple salt mixtures, geological standards and samples from straw CHP and coal-straw PF combustion plants. All samples were run in a nitrogen atmosphere at a heating rate of 10 deg. C/min. In comparison with the standard method, the new methods are objective and have superior repeatability and sensitivity. Furthermore, the two methods enable the melting behavior to be characterized by a continuous measurement of melt fraction versus temperature. Due to this two-dimensional resolution of the results, the STA and HTLM methods provide more information than the standard method. The study of bottom ash and fly ash as well as deposit samples from straw test firings at the Haslev and Slagelse Combined Heat and Power plants resulted in a better understanding of mineral behaviour during straw grate firing. In these tests a number of straws were fired which had been carefully selected for having different qualities with respect to sort and potassium and chlorine contents. By studying bottom ashes from Slagelse it was found that the melting behaviour correlated with the deposition rate on a probe situated at the outlet part of the combustion zone. (EG)

  4. Synthesis and characterization of mibolerone

    Institute of Scientific and Technical Information of China (English)

    YANG Qing; FAN Bo-lin; TANG Rui-ren

    2007-01-01

    A simple and effective route for the synthesis of mibolerone was described starting from the estr-5(10)-en-3,17-dione in four steps with the overall yield of 47.0%. Thus, two methods for key intermediate methylnorandrost were investigated: one(method A) starting from estr-4-en-3,17-dione underwent 3-keto group protected with ethyl orthoformate to give 3-ethoxy-3,5-dien-estr-17-one, the other(method B) from estr-5(10)-en-3,17-dione and protected 3-keto group to give 3,3-dimethoxy-estr-5(10)-7-one in a mild acidic condition. Then, two intermediates were subsequently reacted with methyllithium followed by a mild hydrolytic procedure and gave methylnorandrost with total yield 25.0% and 86.0%, respectively. In the preparation of 6-dehydrogenation product of methylnorandrost, two procedures(method C and method D) were investigated: one was the protected 17α-methyl-17β-hydroxy △3,-5-enol ethers estrendiene brominated and the resulting 6-bromo-19-methylnortestosterone was then immediately dehydrohaloenated to give 6-dehydro-19-methylnortestosterone, the total yield only reaches 36.0%; the other was directly dehydrogenated with chloranil and the yield reaches 75.6% under the optimum conditions: in refluxing tetrahydrofuran,the molar ratio of methylnorandrost to chloranil is 0.66 and reaction time of 5 h. The titled compound and intermediates were characterized by 1H and 13C NMR, IRMS and elemental analysis.

  5. SHAPE CHARACTERIZATION OF CONCRETE AGGREGATE

    Directory of Open Access Journals (Sweden)

    Jing Hu

    2011-05-01

    Full Text Available As a composite material, the performance of concrete materials can be expected to depend on the properties of the interfaces between its two major components, aggregate and cement paste. The microstructure at the interfacial transition zone (ITZ is assumed to be different from the bulk material. In general, properties of conventional concrete have been found favoured by optimum packing density of the aggregate. Particle size is a common denominator in such studies. Size segregation in the ITZ among the binder particles in the fresh state, observed in simulation studies by concurrent algorithm-based SPACE system, additionally governs density as well as physical bonding capacity inside these shell-like zones around aggregate particles. These characteristics have been demonstrated qualitatively pertaining also after maturation of the concrete. Such properties of the ITZs have direct impact on composite properties. Despite experimental approaches revealed effects of aggregate grain shape on different features of material structure (among which density, and as a consequence on mechanical properties, it is still an underrated factor in laboratory studies, probably due to the general feeling that a suitable methodology for shape characterization is not available. A scientific argument hindering progress is the interconnected nature of size and shape. Presently, a practical problem preventing shape effects to be emphasized is the limitation of most computer simulation systems in concrete technology to spherical particles. New developments at Delft University of Technology will make it possible in the near future to generate jammed states, or other high-density fresh particle mixtures of non-spherical particles, which thereupon can be subjected to hydration algorithms. This paper will sketch the outlines of a methodological approach for shape assessment of loose (non-embedded aggregate grains, and demonstrate its use for two types of aggregate, allowing

  6. Surface characterization of platinum electrodes.

    Science.gov (United States)

    Solla-Gullón, José; Rodríguez, Paramaconi; Herrero, Enrique; Aldaz, Antonio; Feliu, Juan M

    2008-03-14

    The quantitative analysis of the different surface sites on platinum samples is attempted from pure voltammetric data. This analysis requires independent knowledge of the fraction of two-dimensional (111) and (100) domains. Specific site-probe reactions are employed to achieve this goal. Irreversibly-adsorbed bismuth and tellurium have been revealed to be sensitive to the presence of (111) terrace domains of different width whereas almost all sites involved in (100) ordered domains have been characterized through germanium adatoms. The experimental protocol follows that used with well-defined single-crystal electrodes and, therefore, requires careful control of the surface cleanliness. Platinum basal planes and their vicinal stepped surfaces have been employed to obtain calibration plots between the charge density measured under the adatom redox peak, specific for the type of surface site, and the corresponding terrace size. The evaluation of the (100) bidimensional domains can also be achieved using the voltammetric profiles, once the fraction of (111) ordered domains present in the polyoriented platinum has been determined and their featureless contribution has been subtracted from the whole voltammetric response. Using that curve, it is possible to perform a deconvolution of the adsorption states of the polycrystalline sample different from those related to (111) domains. The fraction of (100)-related states in the deconvoluted voltammogram can then be compared to that expected from the independent estimation coming from the charge involved in the redox process undergone by the irreversibly-adsorbed germanium and thus check the result of the deconvolution. The information about the surface-site distribution can also be applied to analyze the voltammetric profile of nanocrystalline platinum electrodes. PMID:18309392

  7. Novel characterization of welding fumes

    International Nuclear Information System (INIS)

    Complete text of publication follows. The lung deposition of welding fume comprised of a large number of primary nanoparticles, occurs predominantly in the alveolar region. The particle size distribution of welding fumes is an important factor determining the bioaccessibility of metal components and the hazard potential of pro-inflammatory effects driven largely by soluble and insoluble transition metals. Several techniques are frequently used for determining the particle size distribution of different welding fumes. A scanning mobility particle sizer (SMPS) offers the opportunity of temporal particle-size distribution measurements and to follow the changes in particle number concentration, a transmission electron microscope (TEM) is capable of visualizing the individual particle morphology and measuring the particle size of primary particles. Are the results obtained with these two techniques comparable? To answer this question welding fumes were generated by different welding methods and examined by a SMPS in the range of 10 to 487 nanometers. The SMPS instrument measures the size distribution of fine particles by separating particles based on electrical-mobility. Particles of a selected size are detected optically, using a detection technology in which small particle visibility is enhanced by growing the particles in a condensing butyl alcohol vapour. Samples were collected on TEM grids made of nickel, copper and silicon for primary particle characterization by TEM. Particle size distributions with both analytical techniques were determined. The most obvious features of the TEM analysis were that the primary welding fume particles had a tendency to form chainlike agglomerates in case of all welding, and almost no individual primary particles were found. It is quite unclear how these agglomerates are detected by the SMPS. An important finding of the chemical analysis of the particles by TEM was that the larger particles contained cores of more volatile components

  8. Some Characterizations of Convex Interval Games

    NARCIS (Netherlands)

    Brânzei, R.; Tijs, S.H.; Alparslan-Gok, S.Z.

    2008-01-01

    This paper focuses on new characterizations of convex interval games using the notions of exactness and superadditivity. We also relate big boss interval games with concave interval games and obtain characterizations of big boss interval games in terms of exactness and subadditivity.

  9. Axiomatic Characterizations of IVF Rough Approximation Operators

    Directory of Open Access Journals (Sweden)

    Guangji Yu

    2014-01-01

    Full Text Available This paper is devoted to the study of axiomatic characterizations of IVF rough approximation operators. IVF approximation spaces are investigated. The fact that different IVF operators satisfy some axioms to guarantee the existence of different types of IVF relations which produce the same operators is proved and then IVF rough approximation operators are characterized by axioms.

  10. Characterization monitoring & sensor technology crosscutting program

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-08-01

    The purpose of the Characterization, Monitoring, and Sensor Technology Crosscutting Program (CMST-CP) is to deliver appropriate characterization, monitoring, and sensor technology (CMST) to the OFfice of Waste Management (EM-30), the Office of Environmental Restoration (EM-40), and the Office of Facility Transition and Management (EM-60).

  11. Traceable surface characterization using replica moulding technology

    DEFF Research Database (Denmark)

    Gasparin, Stefania; Hansen, Hans Nørgaard; Tosello, Guido

    2011-01-01

    these problems, surface replication is considered as a method to make feasible the characterization of the polished specimens. This paper focuses on the investigation of surface characterization based on replication methods using soft and hard polymer casting. The study deals with the evaluation...

  12. Multi-scale characterization of monument limestones

    CERN Document Server

    Beck, K; Al-Mukhtar, M; Rozenbaum, Olivier

    2003-01-01

    Among the parameters influencing stone deterioration, moisture and water movements through the pore network are essential. This communication presents differents methods to characterize stones and to determinate the water transfer properties. Results are analysed for two limestones having similar total porosity, but characterized by different pore networks. These different porous systems govern dissimilar water properties.

  13. Rheological characterization of media containing Penicillium chrysogenum

    DEFF Research Database (Denmark)

    Pedersen, Annemarie Gade; Bundgaard-Nielsen, Mikael; Nielsen, Jens;

    1993-01-01

    Samples from fed-batch fermentations of Penicillium chrysogenum on complex medium are rheologically characterized. The behavior is well described by a power law model for which the parameters are estimates. Furthermore, two types of model media are characterized and compared with the real...

  14. Synthesis, FT-IR characterization and crystal structure of aqua-(5,10,15,20-tetra-phenyl-porphyrinato-κ(4) N)manganese(III) tri-fluoro-methane-sulfonate.

    Science.gov (United States)

    Harhouri, Wafa; Mchiri, Chadlia; Najmudin, Shabir; Bonifácio, Cecilia; Nasri, Habib

    2016-05-01

    In the title salt, [Mn(C44H28N4)(H2O)](CF3SO3) or [Mn(III)(TPP)(H2O)](CF3SO3) (where TPP is the dianion of 5,10,15,20-tetra-phenyl-porphyrin), the Mn(III) cation is chelated by the four pyrrole N atoms of the porphyrinate anion and additionally coordinated by an aqua ligand in an apical site, completing the distorted square-pyramidal coordination environment. The average Mn-N(pyrrole) bond length is 1.998 (9) Å and the Mn-O(aqua) bond length is 2.1057 (15) Å. The central Mn(III) ion is displaced by 0.1575 (5) Å from the N4C20 mean plane of the porphyrinate anion towards the apical aqua ligand. The porphyrinate macrocycle exhibits a moderate ruffling and strong saddle deformations. In the crystal lattice, the [Mn(III)(TPP)(H2O)](+) cation and the tri-fluoro-methane-sulfonate counter-ions are arranged in alternating planes packed along [001]. The components are linked together through O-H⋯O hydrogen bonds and much weaker C-H⋯O and C-H⋯F inter-actions. The crystal packing is further stabilized by weak C-H⋯π inter-actions involving the pyrrole and phenyl rings of the porphyrin moieties. PMID:27308027

  15. Characterization of MIPAS elevation pointing

    Directory of Open Access Journals (Sweden)

    M. Kiefer

    2007-01-01

    Full Text Available Sufficient knowledge of the pointing is essential for analyses of limb emission measurements. The scientific retrieval processor for MIPAS on ENVISAT operated at IMK allows the retrieval of pointing information in terms of tangent altitudes along with temperature. The retrieved tangent altitudes are independent of systematic offsets in the engineering Line-Of-Sight (LOS information delivered with the ESA Level 1b product. The difference of pointing retrieved from the reprocessed high resolution MIPAS spectra and the engineering pointing information was examined with respect to spatial/temporal behaviour. Among others the following characteristics of MIPAS pointing could be identified: Generally the engineering tangent altitudes are too high by 0–1.8 km with conspicuous variations in this range over time. Prior to December of 2003 there was a drift of about 50–100 m/h, which was due to a slow change in the satellite attitude. A correction of this attitude is done twice a day, which leads to discontinuities in the order of 1–1.5 km in the tangent altitudes. Occasionally discontinuities up to 2.5 km are found, as already reported from MIPAS and SCIAMACHY observations. After an update of the orbit position software in December 2003 values of drift and jumps are much reduced. There is a systematic difference in the mispointing between the poles which amounts to 1.5–2 km, i.e. there is a conspicuous orbit-periodic feature. The analysis of the correlation between the instrument's viewing angle azimuth and differential mispointing supports the hypotheses that a major part of this latter phenomenon can be attributed to an error in the roll angle of the satellite/instrument system of approximately 42 mdeg. One conclusion is that ESA level 2 data should be compared to other data exclusively on tangent pressure levels. Complementary to IMK data, ESA operational LOS calibration results were used to characterize MIPAS pointing. For this purpose

  16. Characterization of MIPAS elevation pointing

    Science.gov (United States)

    Kiefer, M.; von Clarmann, T.; Grabowski, U.; de Laurentis, M.; Mantovani, R.; Milz, M.; Ridolfi, M.

    2007-03-01

    Sufficient knowledge of the pointing is essential for analyses of limb emission measurements. The scientific retrieval processor for MIPAS on ENVISAT operated at IMK allows the retrieval of pointing information in terms of tangent altitudes along with temperature. The retrieved tangent altitudes are independent of systematic offsets in the engineering Line-Of-Sight (LOS) information delivered with the ESA Level 1b product. The difference of pointing retrieved from the reprocessed high resolution MIPAS spectra and the engineering pointing information was examined with respect to spatial/temporal behaviour. Among others the following characteristics of MIPAS pointing could be identified: Generally the engineering tangent altitudes are too high by 0-1.8 km with conspicuous variations in this range over time. Prior to December of 2003 there was a drift of about 50-100 m/h, which was due to a slow change in the satellite attitude. A correction of this attitude is done twice a day, which leads to discontinuities in the order of 1-1.5 km in the tangent altitudes. Occasionally discontinuities up to 2.5 km are found, as already reported from MIPAS and SCIAMACHY observations. After an update of the orbit position software in December 2003 values of drift and jumps are much reduced. There is a systematic difference in the mispointing between the poles which amounts to 1.5-2 km, i.e. there is a conspicuous orbit-periodic feature. The analysis of the correlation between the instrument's viewing angle azimuth and differential mispointing supports the hypotheses that a major part of this latter phenomenon can be attributed to an error in the roll angle of the satellite/instrument system of approximately 42 mdeg. One conclusion is that ESA level 2 data should be compared to other data exclusively on tangent pressure levels. Complementary to IMK data, ESA operational LOS calibration results were used to characterize MIPAS pointing. For this purpose MIPAS is used as a radiometer

  17. Double tracks test site characterization report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    This report presents the results of site characterization activities performed at the Double Tracks Test Site, located on Range 71 North, of the Nellis Air Force Range (NAFR) in southern Nevada. Site characterization activities included reviewing historical data from the Double Tracks experiment, previous site investigation efforts, and recent site characterization data. The most recent site characterization activities were conducted in support of an interim corrective action to remediate the Double Tracks Test Site to an acceptable risk to human health and the environment. Site characterization was performed using a phased approach. First, previously collected data and historical records sere compiled and reviewed. Generalized scopes of work were then prepared to fill known data gaps. Field activities were conducted and the collected data were then reviewed to determine whether data gaps were filled and whether other areas needed to be investigated. Additional field efforts were then conducted, as required, to adequately characterize the site. Characterization of the Double Tracks Test Site was conducted in accordance with the US Department of Energy`s (DOE) Streamlined Approach for Environmental Restoration (SAFER).

  18. Double tracks test site characterization report

    International Nuclear Information System (INIS)

    This report presents the results of site characterization activities performed at the Double Tracks Test Site, located on Range 71 North, of the Nellis Air Force Range (NAFR) in southern Nevada. Site characterization activities included reviewing historical data from the Double Tracks experiment, previous site investigation efforts, and recent site characterization data. The most recent site characterization activities were conducted in support of an interim corrective action to remediate the Double Tracks Test Site to an acceptable risk to human health and the environment. Site characterization was performed using a phased approach. First, previously collected data and historical records sere compiled and reviewed. Generalized scopes of work were then prepared to fill known data gaps. Field activities were conducted and the collected data were then reviewed to determine whether data gaps were filled and whether other areas needed to be investigated. Additional field efforts were then conducted, as required, to adequately characterize the site. Characterization of the Double Tracks Test Site was conducted in accordance with the US Department of Energy's (DOE) Streamlined Approach for Environmental Restoration (SAFER)

  19. Advances on models, characterizations and applications

    CERN Document Server

    Balakrishnan, N; Gebizlioglu, O L

    2005-01-01

    PrefaceContributorsThe Shapes of the Probability Density, Hazard, and Reverse Hazard FunctionsMasaaki SibuyaStochastic Ordering of Risks, Influence of Dependence, and A.S. ConstructionsLudger RüschendorfThe q-Factorial Moments of Discrete q-Distributions and a Characterization of the Euler DistributionCh.A. Charalambides and N. PapadatosOn the Characterization of Distributions Through the Properties of Conditional Expectations of Order StatisticsI. Bairamov and O. GebizliogluCharacterization of the Exponential Distribution by Conditional Expectations of Generalized SpacingsErhard Cramer and Ud

  20. Nanoporous Gold: Fabrication, Characterization, and Applications

    Directory of Open Access Journals (Sweden)

    Michael L. Reed

    2009-12-01

    Full Text Available Nanoporous gold (np-Au has intriguing material properties that offer potential benefits for many applications due to its high specific surface area, well-characterized thiol-gold surface chemistry, high electrical conductivity, and reduced stiffness. The research on np-Au has taken place on various fronts, including advanced microfabrication and characterization techniques to probe unusual nanoscale properties and applications spanning from fuel cells to electrochemical sensors. Here, we provide a review of the recent advances in np-Au research, with special emphasis on microfabrication and characterization techniques. We conclude the paper with a brief outline of challenges to overcome in the study of nanoporous metals.