The Experts below are selected from a list of 1035 Experts worldwide ranked by ideXlab platform
Patrick Gamez - One of the best experts on this subject based on the ideXlab platform.
-
drastic effect of lattice Propionitrile molecules on the spin transition temperature of a 2 2 dipyridylamino s triazine based iron ii complex
Inorganic Chemistry, 2014Co-Authors: Nanthawat Wannarit, Nassim Nassirinia, Saeid Amani, Norberto Masciocchi, Sujittra Youngme, Olivier Roubeau, Simon J Teat, Patrick GamezAbstract:Reaction of iron(II) selenocyanate (obtained from Fe(ClO4)2 and KNCSe) with 2-(N,N-bis(2-pyridyl)amino)-4,6-bis(pentafluorophenoxy)-(1,3,5)triazine (L1F) in Propionitrile produces the compound [Fe(L1F)2(NCSe)2]·2CH3CH2CN (1NCSe·2PrCN), which shows spin-crossover (SCO) properties characterized by a T1/2 of 283 K and a ΔT80 (i.e., temperature range within which 80% of the transition considered occurs) of about 65 K. Upon air exposure, 1NCSe·2PrCN gradually converts to a new SCO species that exhibits different properties, as reflected by T1/2 = 220 K and ΔT80 = 70 K. Various characterization techniques, namely, IR spectroscopy, thermogravimetric analysis, and thermodiffractometric studies, reveal that the new phase is obtained through the loss of the lattice Propionitrile molecules within several days upon air exposure or several hours upon heating above 390 K.
C. M. Kao - One of the best experts on this subject based on the ideXlab platform.
-
biodegradation of Propionitrile by klebsiella oxytoca immobilized in alginate and cellulose triacetate gel
Journal of Hazardous Materials, 2010Co-Authors: Chungyu Chen, Ssuching Chen, M Fingas, C. M. KaoAbstract:A microbial process for the degradation of Propionitrile by Klebsiella oxytoca was studied. The microorganism, K. oxytoca, was isolated from the discharged wastewater of metal plating factory in southern Taiwan and adapted for Propionitrile biodegradation. The free and immobilized cells of K. oxytoca were then examined for their capabilities on degrading Propionitrile under various conditions. Alginate (AL) and cellulose triacetate (CT) techniques were applied for the preparation of immobilized cells. The efficiency and produced metabolic intermediates and end-products of Propionitrile degradation were monitored in bath and continuous bioreactor experiments. Results reveal that up to 100 and 150 mM of Propionitrile could be removed completely by the free and immobilized cell systems, respectively. Furthermore, both immobilized cell systems show higher removal efficiencies in wider ranges of temperature (20-40 degrees C) and pH (6-8) compared with the free cell system. Results also indicate that immobilized cell system could support a higher cell density to enhance the removal efficiency of Propionitrile. Immobilized cells were reused in five consecutive degradation experiments, and up to 99% of Propionitrile degradation was observed in each batch test. This suggests that the activity of immobilized cells can be maintained and reused throughout different Propionitrile degradation processes. A two-step pathway was observed for the biodegradation of Propionitrile. Propionamide was first produced followed by propionic acid and ammonia. Results suggest that nitrile hydratase and amidase were involved in the degradation pathways of K. oxytoca. In the continuous bioreactor, both immobilized cells were capable of removing 150 mM of Propionitriles completely within 16h, and the maximum Propionitriles removal rates using AL and CT immobilized beads were 5.04 and 4.98 mM h(-1), respectively. Comparing the removal rates obtained from batch experiments with immobilized cells (AL and CT were 1.57 and 2.18 mM h(-1) at 150 mM of Propionitrile, respectively), the continuous-flow bioreactor show higher potential for practical application.
-
biodegradation of Propionitrile by klebsiella oxytoca immobilized in alginate and cellulose triacetate gel
Journal of Hazardous Materials, 2010Co-Authors: Chungyu Chen, Ssuching Chen, M Fingas, C. M. KaoAbstract:Abstract A microbial process for the degradation of Propionitrile by Klebsiella oxytoca was studied. The microorganism, K. oxytoca , was isolated from the discharged wastewater of metal plating factory in southern Taiwan and adapted for Propionitrile biodegradation. The free and immobilized cells of K. oxytoca were then examined for their capabilities on degrading Propionitrile under various conditions. Alginate (AL) and cellulose triacetate (CT) techniques were applied for the preparation of immobilized cells. The efficiency and produced metabolic intermediates and end-products of Propionitrile degradation were monitored in bath and continuous bioreactor experiments. Results reveal that up to 100 and 150 mM of Propionitrile could be removed completely by the free and immobilized cell systems, respectively. Furthermore, both immobilized cell systems show higher removal efficiencies in wider ranges of temperature (20–40 °C) and pH (6–8) compared with the free cell system. Results also indicate that immobilized cell system could support a higher cell density to enhance the removal efficiency of Propionitrile. Immobilized cells were reused in five consecutive degradation experiments, and up to 99% of Propionitrile degradation was observed in each batch test. This suggests that the activity of immobilized cells can be maintained and reused throughout different Propionitrile degradation processes. A two-step pathway was observed for the biodegradation of Propionitrile. Propionamide was first produced followed by propionic acid and ammonia. Results suggest that nitrile hydratase and amidase were involved in the degradation pathways of K. oxytoca . In the continuous bioreactor, both immobilized cells were capable of removing 150 mM of Propionitriles completely within 16 h, and the maximum Propionitriles removal rates using AL and CT immobilized beads were 5.04 and 4.98 mM h −1 , respectively. Comparing the removal rates obtained from batch experiments with immobilized cells (AL and CT were 1.57 and 2.18 mM h −1 at 150 mM of Propionitrile, respectively), the continuous-flow bioreactor show higher potential for practical application.
-
Enzymatic degradation of nitriles by Klebsiella oxytoca
Applied Microbiology and Biotechnology, 2006Co-Authors: C. M. Kao, K. F. Chen, J. K. Liu, S. M. Chou, S. C. ChenAbstract:Klebsiella oxytoca , isolated from cyanide-containing wastewater, was able to utilize many nitriles as sole source of nitrogen. The major objective of this study was to explore the ability of K. oxytoca to utilize some nitriles and then further evaluate the pathways of transformation of cyanide compounds by K. oxytoca . Results from this study indicate that succinonitrile and valeronitrile were the most optimal sources of nitrogen for the growth of K. oxytoca . The biodegradation of acetonitrile proceeded with the formation of acetamide followed by acetic acid. The production of ammonia was also detected in this biodegradation experiment. Similar results were observed in the Propionitrile biodegradation experiments. Collectively, this study suggests that the breakdown of acetonitrile or Propionitrile by this bacterium was via a two-step enzymatic hydrolysis with amides as the intermediates and organic acids plus with ammonia as the end products.
Gerrit Boschloo - One of the best experts on this subject based on the ideXlab platform.
-
Role of the Triiodide/Iodide Redox Couple in Dye Regeneration in p‑Type Dye-Sensitized Solar Cells
2016Co-Authors: Elizabeth A Gibson, Loic Le Pleux, Jerome Fortage, Yann Pellegrin, Errol Blart, Fabrice Odobel, Anders Hagfeldt, Gerrit BoschlooAbstract:A series of perylene dyes with different optical and electronic properties have been used as photosensitizers in NiO-based p-type dye-sensitized solar cells. A key target is to develop dyes that absorb light in the red to near-infrared region of the solar spectrum in order to match photoanodes optically in tandem devices; however, the photocurrent produced was found to decrease dramatically as the absorption maxima of the dye used was varied from 517 to 565 nm and varied strongly with the electrolyte solvent (acetonitrile, Propionitrile, or propylene carbonate). To determine the limitations of the energy properties of the dye molecules and to provide guidelines for future sensitizer design, we have determined the redox potentials of the diiodide radical intermediate involved in the charge-transfer reactions in different solvents using photomodulated voltammetry. E°(I3–/I2•–) (V vs Fe(Cp)2+/0) = −0.64 for propylene carbonate, −0.82 for acetonitrile, and −0.87 for Propionitrile. Inefficient regeneration of the sensitizer appears to be the efficiency-limiting step in the device, and the values presented here will be used to design more efficient dyes, with more cathodic reduction potentials, for photocathodes in tandem dye-sensitized solar cells
-
role of the triiodide iodide redox couple in dye regeneration in p type dye sensitized solar cells
Langmuir, 2012Co-Authors: Elizabeth A Gibson, Loic Le Pleux, Jerome Fortage, Yann Pellegrin, Errol Blart, Fabrice Odobel, Anders Hagfeldt, Gerrit BoschlooAbstract:A series of perylene dyes with different optical and electronic properties have been used as photosensitizers in NiO-based p-type dye-sensitized solar cells. A key target is to develop dyes that absorb light in the red to near-infrared region of the solar spectrum in order to match photoanodes optically in tandem devices; however, the photocurrent produced was found to decrease dramatically as the absorption maxima of the dye used was varied from 517 to 565 nm and varied strongly with the electrolyte solvent (acetonitrile, Propionitrile, or propylene carbonate). To determine the limitations of the energy properties of the dye molecules and to provide guidelines for future sensitizer design, we have determined the redox potentials of the diiodide radical intermediate involved in the charge-transfer reactions in different solvents using photomodulated voltammetry. E°(I3–/I2•–) (V vs Fe(Cp)2+/0) = −0.64 for propylene carbonate, −0.82 for acetonitrile, and −0.87 for Propionitrile. Inefficient regeneration of ...
Elizabeth A Gibson - One of the best experts on this subject based on the ideXlab platform.
-
Role of the Triiodide/Iodide Redox Couple in Dye Regeneration in p‑Type Dye-Sensitized Solar Cells
2016Co-Authors: Elizabeth A Gibson, Loic Le Pleux, Jerome Fortage, Yann Pellegrin, Errol Blart, Fabrice Odobel, Anders Hagfeldt, Gerrit BoschlooAbstract:A series of perylene dyes with different optical and electronic properties have been used as photosensitizers in NiO-based p-type dye-sensitized solar cells. A key target is to develop dyes that absorb light in the red to near-infrared region of the solar spectrum in order to match photoanodes optically in tandem devices; however, the photocurrent produced was found to decrease dramatically as the absorption maxima of the dye used was varied from 517 to 565 nm and varied strongly with the electrolyte solvent (acetonitrile, Propionitrile, or propylene carbonate). To determine the limitations of the energy properties of the dye molecules and to provide guidelines for future sensitizer design, we have determined the redox potentials of the diiodide radical intermediate involved in the charge-transfer reactions in different solvents using photomodulated voltammetry. E°(I3–/I2•–) (V vs Fe(Cp)2+/0) = −0.64 for propylene carbonate, −0.82 for acetonitrile, and −0.87 for Propionitrile. Inefficient regeneration of the sensitizer appears to be the efficiency-limiting step in the device, and the values presented here will be used to design more efficient dyes, with more cathodic reduction potentials, for photocathodes in tandem dye-sensitized solar cells
-
role of the triiodide iodide redox couple in dye regeneration in p type dye sensitized solar cells
Langmuir, 2012Co-Authors: Elizabeth A Gibson, Loic Le Pleux, Jerome Fortage, Yann Pellegrin, Errol Blart, Fabrice Odobel, Anders Hagfeldt, Gerrit BoschlooAbstract:A series of perylene dyes with different optical and electronic properties have been used as photosensitizers in NiO-based p-type dye-sensitized solar cells. A key target is to develop dyes that absorb light in the red to near-infrared region of the solar spectrum in order to match photoanodes optically in tandem devices; however, the photocurrent produced was found to decrease dramatically as the absorption maxima of the dye used was varied from 517 to 565 nm and varied strongly with the electrolyte solvent (acetonitrile, Propionitrile, or propylene carbonate). To determine the limitations of the energy properties of the dye molecules and to provide guidelines for future sensitizer design, we have determined the redox potentials of the diiodide radical intermediate involved in the charge-transfer reactions in different solvents using photomodulated voltammetry. E°(I3–/I2•–) (V vs Fe(Cp)2+/0) = −0.64 for propylene carbonate, −0.82 for acetonitrile, and −0.87 for Propionitrile. Inefficient regeneration of ...
Hun-soo Byun - One of the best experts on this subject based on the ideXlab platform.
-
high pressure phase equilibria for the binary mixture of co2 3 phenyl Propionitrile and co2 2 phenyl butyronitrile systems
Journal of Supercritical Fluids, 2017Co-Authors: Hun-soo ByunAbstract:Abstract Nitrile groups have strong polarity and show the non-ideal phase equilibria. Phase equilibria for the 3-phenyl Propionitrile and 2-phenyl butyronitrile play an important role as organic solvents in several industrial processes. The solubility curves of binary mixture for 3-phenyl Propionitrile and 2-phenyl butyronitrile in supercritical CO 2 are investigated using a synthetic method at five temperatures of (313.2, 333.2, 353.2, 373.2 and 393.2) K and pressure up to 34.45 MPa. Both CO 2 + 3-phenyl Propionitrile and CO 2 + 2-phenyl butyronitrile systems have critical mixture curves that show maximums in pressure-temperature space between the critical temperatures of CO 2 and 3-phenyl Propionitrile or 2-phenyl butyronitrile. The solubility of CO 2 for two systems at a constant pressure decreases with the increase of temperature. The CO 2 + 3-phenyl Propionitrile and CO 2 + 2-phenyl butyronitrile systems display type-I phase behavior within scope of this work. The experimental results for the CO 2 + 3-phenyl Propionitrile and CO 2 + 2-phenyl butyronitrile binary systems are correlated with Peng-Robinson equation of state using a mixing rule including two adjustable parameters (k ij, η ij ). The critical properties ( p c , T c and ω) and vapor pressure of 3-phenyl Propionitrile and 2-phenyl butyronitrile were estimated with the Joback–Lyderson group contribution and Lee-Kesler method.
-
High pressure phase behavior for the Propionitrile and butyronitrile in supercritical carbon dioxide
Journal of Industrial and Engineering Chemistry, 2010Co-Authors: Sung-hyun Kim, Mi-hwa Park, Jong Sung Lim, Hun-soo ByunAbstract:Abstract Pressure-composition isotherms for the (carbon dioxide + Propionitrile) and (carbon dioxide + butyronitrile) systems are measured in static-type high pressure apparatus at several temperatures of 313.2, 333.2, 353.2, 373.2 and 393.2 K and at pressures range from 3.5 to 16.7 MPa. The carbon dioxide + nitriles systems have continuous critical mixture (local) curves that exhibit maximums in pressure–temperature space between the critical point of carbon dioxide and monomers (Propionitrile or butyronitrile). At a fixed pressure, the solubility of Propionitrile or butyronitrile for the two binary systems increases as the temperature increases. The (carbon dioxide + Propionitrile) and (carbon dioxide + butyronitrile) systems exhibit type-I phase behavior. The experimental results for the (carbon dioxide + Propionitrile) and (carbon dioxide + butyronitrile) systems are correlated with Peng–Robinson equation of state using mixing rule including two adjustable parameters.
