The Experts below are selected from a list of 291 Experts worldwide ranked by ideXlab platform
Richard Mendelsohn - One of the best experts on this subject based on the ideXlab platform.
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partial chain deuteration as an irras probe of conformational order of different regions in Hexadecanoic Acid monolayers at the air water interface
Langmuir, 1996Co-Authors: Arne Gericke, Richard MendelsohnAbstract:External infrared reflection−absorption spectroscopy (IRRAS) of Hexadecanoic Acid-d17 (half deuterated at the tail end) monolayers at the air/water interface has been used to investigate conformational order in both halves of the molecule. The symmetric and asymmetric CH2 stretching vibrations in the liquid-condensed phase were found to be 0.8 and 1.3−1.8 cm-1 lower in frequency respectively than the same vibrations in Hexadecanoic Acid-d3 (terminal methyl deuterated), suggesting substantially higher conformational order near the polar headgroup. Theoretical simulations of the bands reveal that the effect cannot arise from different IRRAS intensities for these vibrations in the two molecules. IRRAS measurements at a series of temperatures between 14 and 27 °C reveal a different average response to increased temperature in the two halves of the chain: conformational disorder is introduced at the tail end at a lower temperature. This work demonstrates that current state-of-the-art IRRAS measurements provid...
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Partial Chain Deuteration as an IRRAS Probe of Conformational Order of Different Regions in Hexadecanoic Acid Monolayers at the Air/Water Interface
Langmuir, 1996Co-Authors: Arne Gericke, Richard MendelsohnAbstract:External infrared reflection−absorption spectroscopy (IRRAS) of Hexadecanoic Acid-d17 (half deuterated at the tail end) monolayers at the air/water interface has been used to investigate conformational order in both halves of the molecule. The symmetric and asymmetric CH2 stretching vibrations in the liquid-condensed phase were found to be 0.8 and 1.3−1.8 cm-1 lower in frequency respectively than the same vibrations in Hexadecanoic Acid-d3 (terminal methyl deuterated), suggesting substantially higher conformational order near the polar headgroup. Theoretical simulations of the bands reveal that the effect cannot arise from different IRRAS intensities for these vibrations in the two molecules. IRRAS measurements at a series of temperatures between 14 and 27 °C reveal a different average response to increased temperature in the two halves of the chain: conformational disorder is introduced at the tail end at a lower temperature. This work demonstrates that current state-of-the-art IRRAS measurements provid...
Jurate Simokaitiene - One of the best experts on this subject based on the ideXlab platform.
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triplet harvesting in poly 9 vinylcarbazole and poly 9 2 3 epoxypropyl carbazole doped with cdse zns quantum dots encapsulated with 16 n carbazolyl Hexadecanoic Acid ligands
Journal of Polymer Science Part B, 2014Co-Authors: Adis Khetubol, Sven Van Snick, Egle Stanislovaityte, Antti Hassinen, Willem Vanderlinden, Yuliar Firdaus, Eduard Fron, Maarten Vlasselaer, Eduardo Coutinogonzalez, Jurate SimokaitieneAbstract:Semiconductor quantum dots (QDs) can be used as alternative for transition metal complexes to harvest the none- missive triplet excitons in organic light-emitting diodes (OLEDs). In search for a QD-based OLED material generating blue emission, poly(9-vinylcarbazole) (PVK) and poly(9-(2,3- epoxypropyl) carbazole) (PEPK) are chosen as host for blue- emitting CdSe/ZnS core/shell QDs. The QDs are encapsulated with 16-(N-carbazolyl) Hexadecanoic Acid (C16), a ligand termi- nated by a carbazole moiety. As alternative for PVK, PEPK, where the lower molecular weight and less extensive excimer formation could promise a better film formation and more extensive exciton hopping, is explored. The efficiencies of sin- glet (U S) and triplet (U T) energy transfer to the C16 capped QDs are estimated by combining stationary photoluminescence spectra and fluorescence decays of pristine polymer films with those of polymer films doped with the QDs. At a loading of 30 wt % of the QDs, U S increases from 12 61% in PVK to 41 62% in PEPK while U T increases from 37 622% in PVK to 72 648% in PEPK. The investigation of the film morphology by atomic force microscopy confirms that the main factor limiting the triplet transfer efficiency in the PVK matrix is the clustering of the C16 capped QDs. V C 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 539-551
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Triplet harvesting in poly(9‐vinylcarbazole) and poly(9‐(2,3‐epoxypropyl)carbazole) doped with CdSe/ZnS quantum dots encapsulated with 16‐(N‐carbazolyl) Hexadecanoic Acid ligands
Journal of Polymer Science Part B: Polymer Physics, 2014Co-Authors: Adis Khetubol, Sven Van Snick, Egle Stanislovaityte, Antti Hassinen, Eduardo Coutino-gonzalez, Willem Vanderlinden, Yuliar Firdaus, Eduard Fron, Maarten Vlasselaer, Jurate SimokaitieneAbstract:Semiconductor quantum dots (QDs) can be used as alternative for transition metal complexes to harvest the none- missive triplet excitons in organic light-emitting diodes (OLEDs). In search for a QD-based OLED material generating blue emission, poly(9-vinylcarbazole) (PVK) and poly(9-(2,3- epoxypropyl) carbazole) (PEPK) are chosen as host for blue- emitting CdSe/ZnS core/shell QDs. The QDs are encapsulated with 16-(N-carbazolyl) Hexadecanoic Acid (C16), a ligand termi- nated by a carbazole moiety. As alternative for PVK, PEPK, where the lower molecular weight and less extensive excimer formation could promise a better film formation and more extensive exciton hopping, is explored. The efficiencies of sin- glet (U S) and triplet (U T) energy transfer to the C16 capped QDs are estimated by combining stationary photoluminescence spectra and fluorescence decays of pristine polymer films with those of polymer films doped with the QDs. At a loading of 30 wt % of the QDs, U S increases from 12 61% in PVK to 41 62% in PEPK while U T increases from 37 622% in PVK to 72 648% in PEPK. The investigation of the film morphology by atomic force microscopy confirms that the main factor limiting the triplet transfer efficiency in the PVK matrix is the clustering of the C16 capped QDs. V C 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 539-551
Arne Gericke - One of the best experts on this subject based on the ideXlab platform.
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partial chain deuteration as an irras probe of conformational order of different regions in Hexadecanoic Acid monolayers at the air water interface
Langmuir, 1996Co-Authors: Arne Gericke, Richard MendelsohnAbstract:External infrared reflection−absorption spectroscopy (IRRAS) of Hexadecanoic Acid-d17 (half deuterated at the tail end) monolayers at the air/water interface has been used to investigate conformational order in both halves of the molecule. The symmetric and asymmetric CH2 stretching vibrations in the liquid-condensed phase were found to be 0.8 and 1.3−1.8 cm-1 lower in frequency respectively than the same vibrations in Hexadecanoic Acid-d3 (terminal methyl deuterated), suggesting substantially higher conformational order near the polar headgroup. Theoretical simulations of the bands reveal that the effect cannot arise from different IRRAS intensities for these vibrations in the two molecules. IRRAS measurements at a series of temperatures between 14 and 27 °C reveal a different average response to increased temperature in the two halves of the chain: conformational disorder is introduced at the tail end at a lower temperature. This work demonstrates that current state-of-the-art IRRAS measurements provid...
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Partial Chain Deuteration as an IRRAS Probe of Conformational Order of Different Regions in Hexadecanoic Acid Monolayers at the Air/Water Interface
Langmuir, 1996Co-Authors: Arne Gericke, Richard MendelsohnAbstract:External infrared reflection−absorption spectroscopy (IRRAS) of Hexadecanoic Acid-d17 (half deuterated at the tail end) monolayers at the air/water interface has been used to investigate conformational order in both halves of the molecule. The symmetric and asymmetric CH2 stretching vibrations in the liquid-condensed phase were found to be 0.8 and 1.3−1.8 cm-1 lower in frequency respectively than the same vibrations in Hexadecanoic Acid-d3 (terminal methyl deuterated), suggesting substantially higher conformational order near the polar headgroup. Theoretical simulations of the bands reveal that the effect cannot arise from different IRRAS intensities for these vibrations in the two molecules. IRRAS measurements at a series of temperatures between 14 and 27 °C reveal a different average response to increased temperature in the two halves of the chain: conformational disorder is introduced at the tail end at a lower temperature. This work demonstrates that current state-of-the-art IRRAS measurements provid...
Adis Khetubol - One of the best experts on this subject based on the ideXlab platform.
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triplet harvesting in poly 9 vinylcarbazole and poly 9 2 3 epoxypropyl carbazole doped with cdse zns quantum dots encapsulated with 16 n carbazolyl Hexadecanoic Acid ligands
Journal of Polymer Science Part B, 2014Co-Authors: Adis Khetubol, Sven Van Snick, Egle Stanislovaityte, Antti Hassinen, Willem Vanderlinden, Yuliar Firdaus, Eduard Fron, Maarten Vlasselaer, Eduardo Coutinogonzalez, Jurate SimokaitieneAbstract:Semiconductor quantum dots (QDs) can be used as alternative for transition metal complexes to harvest the none- missive triplet excitons in organic light-emitting diodes (OLEDs). In search for a QD-based OLED material generating blue emission, poly(9-vinylcarbazole) (PVK) and poly(9-(2,3- epoxypropyl) carbazole) (PEPK) are chosen as host for blue- emitting CdSe/ZnS core/shell QDs. The QDs are encapsulated with 16-(N-carbazolyl) Hexadecanoic Acid (C16), a ligand termi- nated by a carbazole moiety. As alternative for PVK, PEPK, where the lower molecular weight and less extensive excimer formation could promise a better film formation and more extensive exciton hopping, is explored. The efficiencies of sin- glet (U S) and triplet (U T) energy transfer to the C16 capped QDs are estimated by combining stationary photoluminescence spectra and fluorescence decays of pristine polymer films with those of polymer films doped with the QDs. At a loading of 30 wt % of the QDs, U S increases from 12 61% in PVK to 41 62% in PEPK while U T increases from 37 622% in PVK to 72 648% in PEPK. The investigation of the film morphology by atomic force microscopy confirms that the main factor limiting the triplet transfer efficiency in the PVK matrix is the clustering of the C16 capped QDs. V C 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 539-551
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Triplet harvesting in poly(9‐vinylcarbazole) and poly(9‐(2,3‐epoxypropyl)carbazole) doped with CdSe/ZnS quantum dots encapsulated with 16‐(N‐carbazolyl) Hexadecanoic Acid ligands
Journal of Polymer Science Part B: Polymer Physics, 2014Co-Authors: Adis Khetubol, Sven Van Snick, Egle Stanislovaityte, Antti Hassinen, Eduardo Coutino-gonzalez, Willem Vanderlinden, Yuliar Firdaus, Eduard Fron, Maarten Vlasselaer, Jurate SimokaitieneAbstract:Semiconductor quantum dots (QDs) can be used as alternative for transition metal complexes to harvest the none- missive triplet excitons in organic light-emitting diodes (OLEDs). In search for a QD-based OLED material generating blue emission, poly(9-vinylcarbazole) (PVK) and poly(9-(2,3- epoxypropyl) carbazole) (PEPK) are chosen as host for blue- emitting CdSe/ZnS core/shell QDs. The QDs are encapsulated with 16-(N-carbazolyl) Hexadecanoic Acid (C16), a ligand termi- nated by a carbazole moiety. As alternative for PVK, PEPK, where the lower molecular weight and less extensive excimer formation could promise a better film formation and more extensive exciton hopping, is explored. The efficiencies of sin- glet (U S) and triplet (U T) energy transfer to the C16 capped QDs are estimated by combining stationary photoluminescence spectra and fluorescence decays of pristine polymer films with those of polymer films doped with the QDs. At a loading of 30 wt % of the QDs, U S increases from 12 61% in PVK to 41 62% in PEPK while U T increases from 37 622% in PVK to 72 648% in PEPK. The investigation of the film morphology by atomic force microscopy confirms that the main factor limiting the triplet transfer efficiency in the PVK matrix is the clustering of the C16 capped QDs. V C 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 539-551
V. G. Kumar - One of the best experts on this subject based on the ideXlab platform.
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Optical resolution of (±)-Threo-9,10,16-trihydroxy Hexadecanoic Acid using (−)brucine
Journal of the American Oil Chemists' Society, 1998Co-Authors: Navdeep B. Malkar, V. G. KumarAbstract:The optical resolution of (±) threo -9,10,16-trihydroxy Hexadecanoic Acid was achieved by fractional crystallization using (−)brucine. Formation of an estolide during decomposition of the (−)brucine complex was observed to interfere with the separation of the optically pure material. This was corrected by converting the estolide to (+)- threo -9,10,16-trihydroxy Hexadecanoic Acid via alcoholic alkaline hydrolysis followed by neutralization. Enantiomeric purity was determined by chiral lanthanide nuclear magnetic resonance shift reagent.
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optical resolution of threo 9 10 16 trihydroxy Hexadecanoic Acid using brucine
Journal of the American Oil Chemists' Society, 1998Co-Authors: Navdeep B. Malkar, V. G. KumarAbstract:The optical resolution of (±)threo-9,10,16-trihydroxy Hexadecanoic Acid was achieved by fractional crystallization using (−)brucine. Formation of an estolide during decomposition of the (−)brucine complex was observed to interfere with the separation of the optically pure material. This was corrected by converting the estolide to (+)-threo-9,10,16-trihydroxy Hexadecanoic Acid via alcoholic alkaline hydrolysis followed by neutralization. Enantiomeric purity was determined by chiral lanthanide nuclear magnetic resonance shift reagent.