1
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Engdahl A, Grauberger O, Brockhinke A, Schüttpelz M, Huser TR. Switching of Organic Fluorophores by Glycerol‐Sulfite Interactions for Single‐Molecule Super‐Resolution Microscopy. CHEMPHOTOCHEM 2023. [DOI: 10.1002/cptc.202200305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Anders Engdahl
- Bielefeld University: Universitat Bielefeld Department of Physics GERMANY
| | - Oleg Grauberger
- Bielefeld University: Universitat Bielefeld Department of Physics GERMANY
| | - Andreas Brockhinke
- Bielefeld University: Universitat Bielefeld Department of Chemistry GERMANY
| | - Mark Schüttpelz
- Bielefeld University: Universitat Bielefeld Department of Physics GERMANY
| | - Thomas R. Huser
- Bielefeld University: Universitat Bielefeld Department of Physics Universitaetsstr. 25D3-231 33615 Bielefeld GERMANY
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2
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Felsmann D, Lucassen A, Krüger J, Hemken C, Tran LS, Pieper J, Garcia GA, Brockhinke A, Nahon L, Kohse-Höinghaus K. Progress in Fixed-Photon-Energy Time-Efficient Double Imaging Photoelectron/Photoion Coincidence Measurements in Quantitative Flame Analysis. Z PHYS CHEM 2016. [DOI: 10.1515/zpch-2016-0760] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Photoelectron photoion coincidence (PEPICO) spectroscopy as an attractive new technique for
combustion analysis was used in a fixed-photon-energy configuration to provide quantitative
species profiles in laminar premixed flames. While such measurements are conventionally
performed with molecular-beam mass spectrometry (MBMS) using electron ionization (EI) or
vacuum ultraviolet (VUV) photoionization (PI) with synchrotron radiation, these techniques
have some limitations. The possibility to record photoelectron spectra (PES) simultaneously
with photoionization data, providing fingerprint information for reliable species
identification, presents a significant advantage of PEPICO spectroscopy especially in
complex reactive mixtures. The multiplex approach presented here, enhanced by the imaging
capabilities of the electron and ion detection in the so-called double-imaging PEPICO scheme
(i2PEPICO), provides, in different experimental situations, an
unprecedentedly detailed combustion analysis regarding both species identification and
quantification. Problems and perspectives of the present fixed-photon-energy PEPICO approach
will be discussed.
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Affiliation(s)
- Daniel Felsmann
- Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Arnas Lucassen
- Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany
| | - Julia Krüger
- Synchrotron SOLEIL, L'Orme des Merisiers, St. Aubin, B.P. 48, 91192 Gif-sur-Yvette, France
| | - Christian Hemken
- Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Luc-Sy Tran
- Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Julia Pieper
- Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Gustavo A. Garcia
- Synchrotron SOLEIL, L'Orme des Merisiers, St. Aubin, B.P. 48, 91192 Gif-sur-Yvette, France
| | - Andreas Brockhinke
- Department of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Laurent Nahon
- Synchrotron SOLEIL, L'Orme des Merisiers, St. Aubin, B.P. 48, 91192 Gif-sur-Yvette, France
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3
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Böhling L, Brockhinke A, Kahlert J, Weber L, Harder RA, Yufit DS, Howard JAK, MacBride JAH, Fox MA. Substituent Effects on the Fluorescence Properties ofortho-Carboranes: Unusual Emission Behaviour inC-(2′-Pyridyl)-ortho-carboranes. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201501284] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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4
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Krüger J, Garcia GA, Felsmann D, Moshammer K, Lackner A, Brockhinke A, Nahon L, Kohse-Höinghaus K. Photoelectron-photoion coincidence spectroscopy for multiplexed detection of intermediate species in a flame. Phys Chem Chem Phys 2015; 16:22791-804. [PMID: 25237782 DOI: 10.1039/c4cp02857k] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Complex reactive processes in the gas phase often proceed via numerous reaction steps and intermediate species that must be identified and quantified to develop an understanding of the reaction pathways and establish suitable reaction mechanisms. Here, photoelectron-photoion coincidence (PEPICO) spectroscopy has been applied to analyse combustion intermediates present in a premixed fuel-rich (ϕ = 1.7) ethene-oxygen flame diluted with 25% argon, burning at a reduced pressure of 40 mbar. For the first time, multiplexing fixed-photon-energy PEPICO measurements were demonstrated in a chemically complex reactive system such as a flame in comparison with the scanning "threshold" TPEPICO approach used in recent pioneering combustion investigations. The technique presented here is capable of detecting and identifying multiple species by their cations' vibronic fingerprints, including radicals and pairs or triplets of isomers, from a single time-efficient measurement at a selected fixed photon energy. Vibrational structures for these species have been obtained in very good agreement with scanning-mode threshold photoelectron spectra taken under the same conditions. From such spectra, the temperature in the ionisation volume was determined. Exemplary analysis of species profiles and mole fraction ratios for isomers shows favourable agreement with results obtained by more common electron ionisation and photoionisation mass spectrometry experiments. It is expected that the multiplexing fixed-photon-energy PEPICO technique can contribute effectively to the analysis of chemical reactivity and kinetics in and beyond combustion.
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Affiliation(s)
- Julia Krüger
- Department of Chemistry, Bielefeld University, Universitätsstraße 25, D-33615 Bielefeld, Germany.
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5
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Kahlert J, Böhling L, Brockhinke A, Stammler HG, Neumann B, Rendina LM, Low PJ, Weber L, Fox MA. Syntheses and reductions of C-dimesitylboryl-1,2-dicarba-closo-dodecaboranes. Dalton Trans 2015; 44:9766-81. [DOI: 10.1039/c5dt00758e] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An investigation ofC-dimesitylboryl-ortho-carboranes, 1-(BMes2)-2-R-1,2-C2B10H10(1and2), reveals that the carborane is the electron-acceptor and the mesityl group is the electron-donor in these dyads.
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Affiliation(s)
- Jan Kahlert
- Fakultät für Chemie der Universität Bielefeld
- 33615 Bielefeld
- Germany
| | - Lena Böhling
- Fakultät für Chemie der Universität Bielefeld
- 33615 Bielefeld
- Germany
| | | | | | - Beate Neumann
- Fakultät für Chemie der Universität Bielefeld
- 33615 Bielefeld
- Germany
| | | | - Paul J. Low
- School of Chemistry and Biochemistry
- University of Western Australia
- Crawley
- Australia
| | - Lothar Weber
- Fakultät für Chemie der Universität Bielefeld
- 33615 Bielefeld
- Germany
| | - Mark A. Fox
- Department of Chemistry
- Durham University
- Durham DH1 3LE
- UK
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6
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Abstract
Abstract
Absorption spectroscopy in the ultraviolet (UV) and mid-infrared (MIR)
spectral region has been used in a comparative study for the detection
of formaldehyde in laminar low pressure flames of dimethyl ether (DME)
and methane. Both spectral regions were tested to explore respective
advantages and limitations, especially for the detection of stable
molecules in flames. In the UV, cavity ring-down spectroscopy (CRDS),
a highly sensitive multi-pass absorption technique, has been used for
the detection of formaldehyde in the A − X41
0 hot band at
370 nm. For measurements in the mid-infrared, the fundamental
CO-stretch vibration ν
2 of formaldehyde at 5.9 μm was
used. MIR laser radiation was generated with a pulsed quantum cascade
laser (QCL), a novel laser type which offers high output energies and
excellent beam quality in the MIR. It was shown that MIR-QCL
absorption spectroscopy and UV-CRDS have a comparable sensitivity,
even though only single-pass absorption was used in the
MIR. Additionally, MIR-QCL is clearly superior in terms of the
simplicity of the experimental setup. This shows the large potential
of QCL based laser absorption spectroscopy for the sensitive detection
of trace species in the MIR.
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Affiliation(s)
| | - Julia Koppmann
- Universität Bielefeld, Physikalische Chemie 1, Universitätsstraße 25, 33615 Bielefeld
| | - Alexander Lackner
- Universität Bielefeld, Physikalische Chemie 1, Universitätsstraße 25, 33615 Bielefeld
| | - Andreas Brockhinke
- Universität Bielefeld, Physikalische Chemie 1, Universitätsstraße 25, 33615 Bielefeld
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7
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Krüger J, Koppmann J, Nau P, Brockhinke A, Schenk M, Hansen N, Werner U, Kohse-Höinghaus K. From Precursors to Pollutants: Some Advances in Combustion Chemistry Diagnostics. Eur Chem Tech J 2014. [DOI: 10.18321/ectj174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
The present assessment and prediction of potential pollutant emissions from combustion systems often rely on dedicated combustion models. Their validation depends on the critical examination of the relevant chemical reaction pathways. To this end, a number of combustion diagnostic techniques are available<br />which can probe important chemical constituents in situ, thus providing direct information on the progress of the combustion reactions. Here, some recent experimental advances for the investigation of a suite of targets from molecular intermediates and soot precursors to nascent particles will be presented. Examples include the application of quantum cascade laser absorption spectroscopy (QCLAS), molecular-beam mass<br />spectrometry (MBMS) with different ionization schemes, photoelectron–photoion coincidence (PEPICO) spectroscopy, helium ion microscopy (HIM), and polarization-modulated infrared reflection–absorption spectroscopy (PM-IRRAS).<br /><br />
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8
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Brockhinke A, Koppmann J, Brockhinke R, Kellermann R, Eckert H, Taroata D, Schmid G. Spectroscopic characterization of lithium combustion. ACTA ACUST UNITED AC 2014. [DOI: 10.1557/opl.2014.316] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTIn this work, the exothermic reaction of the chemical energy storage material for stranded renewable energy, lithium is analyzed in carbon dioxide (CO2) and air. Spectroscopic techniques were used to characterize the reaction of bulk lithium pellets of up to 1 g weight. In comparison, power plant applicable combustion of atomized lithium spray was analyzed.Electrical high voltage spark was used to overcome to activation energy of the combustion for the experiments with bulk lithium. The lithium spray was successfully ignited by pre-heating the reaction gases (air and CO2).Radiation temperature of the bulk lithium during reaction in air was calculated to 2260 K. The observed green and red emission of the lithium combustion could be demonstrated in the spectral analysis.In CO2 atmosphere the reaction products were found to be lithium carbonate with little lithium oxide. Beside, lithium carbide could be detected in the reaction product of the combustion of bulk lithium. The gaseous reaction product carbon monoxide (CO), which could be further converted with hydrogen from renewable sources to valuable methanol or gasoline, was detected online by gas analysis.
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9
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Weber L, Halama J, Hanke K, Böhling L, Brockhinke A, Stammler HG, Neumann B, Fox MA. On the ambiguity of 1,3,2-benzodiazaboroles as donor/acceptor functionalities in luminescent molecules. Dalton Trans 2014; 43:3347-63. [DOI: 10.1039/c3dt52836g] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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10
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Weber L, Kahlert J, Brockhinke R, Böhling L, Halama J, Brockhinke A, Stammler HG, Neumann B, Nervi C, Harder RA, Fox MA. C,C'-bis(benzodiazaborolyl)dicarba-closo-dodecaboranes: synthesis, structures, photophysics and electrochemistry. Dalton Trans 2013; 42:10982-96. [PMID: 23793134 DOI: 10.1039/c3dt51125a] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Six new C,C'-bis(benzodiazaborolyl)dicarba-closo-dodecaboranes, 1,A-R2-1,A-C2B10H10, where R represents the group 2-(1,3-Et2-1,3,2-N2BC6H4) or 2-(1,3-Ph2-1,3,2-N2BC6H4) and A is 2, 7 or 12, were synthesized from o-, m-, and p-dicarbadodecaboranes (carboranes) by lithiation and subsequent treatment with the respective 2-bromo-1,3,2-benzodiazaboroles. UV-visible and fluorescence spectra of all carboranes display low energy charge transfer emissions. While such emissions with Stokes shifts between 17,330 and 21,290 cm(-1) are typical for C,C'-bis(aryl)-ortho-carboranes, the observed low-energy emissions with Stokes shifts between 8320 and 15,170 cm(-1) for the meta- and para-isomers are unusual as high-energy emissions are typical for meta- and para-dicarbadodecaboranes. Fluorescence quantum yields (φF) for the novel 1,7- and 1,12-bis(benzodiazaborolyl)-carboranes depend on the substituents at the nitrogen atoms of the heterocycle. Thus, the para-carborane with N-ethyl substituents 1,12-(1',3'-Et2-1',3',2'-N2BC6H4)2-1,12-C2B10H10 has a φF value of 41% in cyclohexane solution and only of 9% in the solid state, whereas the analogous 1,12-(1',3'-Ph2-1',3',2'-N2BC6H4)2-1,12-C2B10H10 shows quantum yields of 3% in cyclohexane solution and 72% in the solid state. X-ray crystallographic, computational and cyclic voltammetry studies for these carboranes are also presented.
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Affiliation(s)
- Lothar Weber
- Fakultät für Chemie der Universität Bielefeld, 33615 Bielefeld, Germany.
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11
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Weber L, Halama J, Böhling L, Brockhinke A, Chrostowska A, Darrigan C, Dargelos A, Stammler H, Neumann B. 1,3,2‐Benzodiazaboroles with 1,3‐Pentafluorophenyl and Tetrafluoropyridyl Substituents as Building Blocks in Luminescent Compounds. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201300319] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Lothar Weber
- Fakultät für Chemie der Universität Bielefeld, 33615 Bielefeld, Germany, http://www.Uni‐bielefeld.de
| | - Johannes Halama
- Fakultät für Chemie der Universität Bielefeld, 33615 Bielefeld, Germany, http://www.Uni‐bielefeld.de
| | - Lena Böhling
- Fakultät für Chemie der Universität Bielefeld, 33615 Bielefeld, Germany, http://www.Uni‐bielefeld.de
| | - Andreas Brockhinke
- Fakultät für Chemie der Universität Bielefeld, 33615 Bielefeld, Germany, http://www.Uni‐bielefeld.de
| | - Anna Chrostowska
- IPREM, UMR 5254, Université de Pau et Pays de l'Adour, 64000 Pau, France
| | - Clovis Darrigan
- IPREM, UMR 5254, Université de Pau et Pays de l'Adour, 64000 Pau, France
| | - Alain Dargelos
- IPREM, UMR 5254, Université de Pau et Pays de l'Adour, 64000 Pau, France
| | - Hans‐Georg Stammler
- Fakultät für Chemie der Universität Bielefeld, 33615 Bielefeld, Germany, http://www.Uni‐bielefeld.de
| | - Beate Neumann
- Fakultät für Chemie der Universität Bielefeld, 33615 Bielefeld, Germany, http://www.Uni‐bielefeld.de
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Weber L, Kahlert J, Böhling L, Brockhinke A, Stammler HG, Neumann B, Harder RA, Low PJ, Fox MA. Electrochemical and spectroelectrochemical studies of C-benzodiazaborolyl-ortho-carboranes. Dalton Trans 2013. [DOI: 10.1039/c2dt32378h] [Citation(s) in RCA: 85] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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13
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Weber L, Kahlert J, Brockhinke R, Böhling L, Brockhinke A, Stammler HG, Neumann B, Harder RA, Fox MA. Luminescence properties of C-diazaborolyl-ortho-carboranes as donor-acceptor systems. Chemistry 2012; 18:8347-57. [PMID: 22623079 DOI: 10.1002/chem.201200390] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Indexed: 11/08/2022]
Abstract
Seven derivatives of 1,2-dicarbadodecaborane (ortho-carborane, 1,2-C(2)B(10)H(12)) with a 1,3-diethyl- or 1,3-diphenyl-1,3,2-benzodiazaborolyl group on one cage carbon atom were synthesized and structurally characterized. Six of these compounds showed remarkable low-energy fluorescence emissions with large Stokes shifts of 15100-20260 cm(-1) and quantum yields (Φ(F)) of up to 65% in the solid state. The low-energy fluorescence emission, which was assigned to a charge-transfer (CT) transition between the cage and the heterocyclic unit, depended on the orientation (torsion angle, ψ) of the diazaborolyl group with respect to the cage C-C bond. In cyclohexane, two compounds exhibited very weak dual fluorescence emissions with Stokes shifts of 15660-18090 cm(-1) for the CT bands and 1960-5540 cm(-1) for the high-energy bands, which were assigned to local transitions within the benzodiazaborole units (local excitation, LE), whereas four compounds showed only CT bands with Φ(F) values between 8-32%. Two distinct excited singlet-state (S(1)) geometries, denoted S(1)(LE) and S(1)(CT), were observed computationally for the benzodiazaborolyl-ortho-carboranes, the population of which depended on their orientation (ψ). TD-DFT calculations on these excited state geometries were in accord with their CT and LE emissions. These C-diazaborolyl-ortho-carboranes were viewed as donor-acceptor systems with the diazaborolyl group as the donor and the ortho-carboranyl group as the acceptor.
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Affiliation(s)
- Lothar Weber
- Fakultät für Chemie der Universität Bielefeld, 33615 Bielefeld, Germany.
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14
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Kuhtz H, Cheng F, Schwedler S, Böhling L, Brockhinke A, Weber L, Parab K, Jäkle F. Luminescent Diazaborolyl-Functionalized Polystyrene. ACS Macro Lett 2012; 1:555-559. [PMID: 35607060 DOI: 10.1021/mz300071f] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
We present two different procedures for the synthesis of poly[4-(1',3'-diethyl-1',3',2'-benzodiazaborolyl)styrene] (3a) and poly[4-(1',3'-diphenyl-1',3',2'-benzodiazaborolyl)styrene] (3b). The new polymers were fully characterized by GPC, multinuclear NMR, and elemental analysis. The thermal properties and stability were studied by DSC and TGA, and the optical characteristics were examined by absorption and time-resolved fluorescence spectroscopy. Remarkably high quantum yields of up to 77% were measured. In comparison to molecular species we found significantly shorter lifetimes, likely as a result of incorporation of the chromophores into the polymer structure.
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Affiliation(s)
- Henry Kuhtz
- Universität Bielefeld, Universitätsstraße 25, D-33615,
Germany
| | - Fei Cheng
- Department
of Chemistry, Rutgers University—Newark, 73
Warren Street, Newark, New Jersey 07102, United States
| | | | - Lena Böhling
- Universität Bielefeld, Universitätsstraße 25, D-33615,
Germany
| | | | - Lothar Weber
- Universität Bielefeld, Universitätsstraße 25, D-33615,
Germany
| | - Kshitij Parab
- Department
of Chemistry, Rutgers University—Newark, 73
Warren Street, Newark, New Jersey 07102, United States
| | - Frieder Jäkle
- Department
of Chemistry, Rutgers University—Newark, 73
Warren Street, Newark, New Jersey 07102, United States
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15
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Weber L, Eickhoff D, Kahlert J, Böhling L, Brockhinke A, Stammler HG, Neumann B, Fox MA. Diazaborolyl-boryl push–pull systems with ethynylene–arylene bridges as ‘turn-on’ fluoride sensors. Dalton Trans 2012; 41:10328-46. [DOI: 10.1039/c2dt30438d] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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16
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Weber L, Kuhtz H, Böhling L, Brockhinke A, Chrostowska A, Dargelos A, Mazière A, Stammler HG, Neumann B. Syntheses of rod-shaped fluorescent 1,3,2-benzodiazaboroles with phosphonium, and phosphane chalcogenide acceptor functions. Dalton Trans 2012; 41:10440-52. [DOI: 10.1039/c2dt30666b] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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17
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Weber L, Eickhoff D, Marder TB, Fox MA, Low PJ, Dwyer AD, Tozer DJ, Schwedler S, Brockhinke A, Stammler HG, Neumann B. Experimental and Theoretical Studies on Organic D-π-A Systems Containing Three-Coordinate Boron Moieties as both π-Donor and π-Acceptor. Chemistry 2011; 18:1369-82. [DOI: 10.1002/chem.201102059] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Indexed: 11/07/2022]
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18
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Schwedler S, Eickhoff D, Brockhinke R, Cherian D, Weber L, Brockhinke A. Solvatochromism and fluoride sensing of thienyl-containing benzodiazaboroles. Phys Chem Chem Phys 2011; 13:9301-10. [PMID: 21475763 DOI: 10.1039/c0cp02023k] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Stefanie Schwedler
- Physikalische Chemie I, Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany.
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Köhler M, Brockhinke A, Braun-Unkhoff M, Kohse-Höinghaus K. Quantitative Laser Diagnostic and Modeling Study of C2 and CH Chemistry in Combustion. J Phys Chem A 2010; 114:4719-34. [DOI: 10.1021/jp908242y] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Markus Köhler
- Department of Chemistry, Bielefeld University, Universitätsstrasse 25, D-33615 Bielefeld, Germany, and Institut für Verbrennungstechnik, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Pfaffenwaldring 38-40, D-70569 Stuttgart, Germany
| | - Andreas Brockhinke
- Department of Chemistry, Bielefeld University, Universitätsstrasse 25, D-33615 Bielefeld, Germany, and Institut für Verbrennungstechnik, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Pfaffenwaldring 38-40, D-70569 Stuttgart, Germany
| | - Marina Braun-Unkhoff
- Department of Chemistry, Bielefeld University, Universitätsstrasse 25, D-33615 Bielefeld, Germany, and Institut für Verbrennungstechnik, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Pfaffenwaldring 38-40, D-70569 Stuttgart, Germany
| | - Katharina Kohse-Höinghaus
- Department of Chemistry, Bielefeld University, Universitätsstrasse 25, D-33615 Bielefeld, Germany, and Institut für Verbrennungstechnik, Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR), Pfaffenwaldring 38-40, D-70569 Stuttgart, Germany
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20
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Kohse-Höinghaus K, Schocker A, Kasper T, Kamphus M, Brockhinke A. Combination of Laser- and Mass-Spectroscopic Techniques for the Investigation of Fuel-Rich Flames. Z PHYS CHEM 2009. [DOI: 10.1524/zpch.219.5.583.64326] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Soot is one of the most important pollutants originating from combustion. Despite recent advances in the measurement of size and composition of soot particles, their actual formation mechanism is still under debate. It depends on fuel, stoichiometry, temperature, flow conditions and the concentration of a large number of intermediate species. An adequate characterization of this complex reaction system generally requires the use of several complementary techniques.
In this article, we present measurements aiming to study reactions in fuel-rich flames using several complementary techniques. Only with a combination of optical and mass-spectrometric measurements, important features of the early polyaromatic hydrocarbon (PAH) and soot formation chemistry are accessible in detail. Three different techniques are combined to investigate one-dimensional laboratory flames on the same low-pressure burner and their respective merits are discussed: (i) cavity ring-down spectroscopy (CRDS) for the detection of small radicals and measurement of the temperature, (ii) mass spectrometry with electron-impact (EI) ionization in order to measure species with molecular weights up to m/e = 90, and (iii) mass spectrometry with resonantly-enhanced multi-photon ionization (REMPI) to distinguish isomers with masses up to m/e = 178. Measurements of this type may prove a valuable input to improve kinetic and combustion models.
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Struckmeier U, Oßwald P, Kasper T, Böhling L, Heusing M, Köhler M, Brockhinke A, Kohse-Höinghaus K. Sampling Probe Influences on Temperature and Species Concentrations in Molecular Beam Mass Spectroscopic Investigations of Flat Premixed Low-pressure Flames. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.2009.6049] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
New operating regimes for engines and combustors and the advocated use of non-conventional transportation fuels demand investigation of the combustion chemistry of different classes of chemicals, especially under premixed conditions. Detailed species compositions during combustion are needed to estimate hazardous emissions, and models for their prediction must be validated for the intended combustion conditions.Molecular-beam mass spectrometry (MBMS) is a common technique to measure quantitative species concentrations in flames. It is widely employed to characterize the flame chemistry of laminar premixed combustion, and it has been complemented with optical measurements for the detection of a number of molecular species and radicals. Significant progress has been made in recent studies through the introduction of synchrotron-based MBMS instruments. They have improved the identification process by using tunable vacuum-ultraviolet radiation for photoionization of the species to be detected, and isomer-specific measurements are now almost routinely possible. Along with quantitative species measurements, the temperature profile is needed as input parameter for chemical kinetic modeling. It is usually determined either using thermocouples or laser spectroscopic techniques.It is an ongoing discussion how sampling probes affect these measurements, and how MBMS results can be compared to combustion modeling. The present article is intended to contribute to this discussion by providing optical and MBMS results obtained with several sampling configurations.
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22
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Weber L, Werner V, Fox MA, Marder TB, Schwedler S, Brockhinke A, Stammler HG, Neumann B. Synthetic, structural, photophysical and computational studies on 2-arylethynyl-1,3,2-diazaboroles. Dalton Trans 2009:2823-31. [PMID: 19333506 DOI: 10.1039/b821208b] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New 2-arylalkynyl benzo-1,3,2-diazaboroles, 2-(4'-XC(6)H(4)C[triple bond, length as m-dash]C)-1,3-Et(2)-1,3,2-N(2)BC(6)H(4) (X =Me ; MeO ; MeS ; Me(2)N ), were prepared from B-bromodiazaborole, 2-Br-1,3-Et(2)-1,3,2-N(2)BC(6)H(4), with the appropriate lithiated arylacetylene, ArC[triple bond, length as m-dash]CLi. Molecular structures of , and were determined by X-ray diffraction studies. UV-vis and luminescence spectroscopic studies on these diazaboroles reveal intense blue/violet fluorescence with very large quantum yields of 0.89-0.99 for . The experimental findings were complemented by DFT and TD-DFT calculations. The Stokes shift of only 2600 cm(-1) for , compared to Stokes shifts in the range of 5900-7300 cm(-1) for , is partly explained by the different electronic structures found in compared to (X = H). The HOMO is mainly located on the aryl group in and on the diazaborolyl group in whereas the LUMOs are largely aryl in character for all compounds. Thus, in contrast to other conjugated systems containing three-coordinate boron centers such as B(Mes)(2), (Mes = 2,4,6-Me(3)C(6)H(2)), in which the boron serves as a pi-acceptor, the 10-pi electron benzodiazaborole moiety appears to function as a pi-donor moiety.
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Affiliation(s)
- Lothar Weber
- Universität Bielefeld, Fakultät für Chemie, Anorganische Chemie, Universitätsstr. 25, 33615 Bielefeld, Germany.
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Schwedler S, Kohse-Höinghaus K, Brockhinke R, Brockhinke A. Investigation Of Excited-State Relaxation In Single-Tryptophan-And Other Proteins Via Multidimensional Static And Time-Resolved Fluorescence. Biophys J 2009. [DOI: 10.1016/j.bpj.2008.12.136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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24
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Weber L, Werner V, Fox MA, Marder TB, Schwedler S, Brockhinke A, Stammler HG, Neumann B. Synthetic, structural, photophysical and computational studies of π-conjugated bis- and tris-1,3,2-benzodiazaboroles and related bis(boryl) dithiophenes. Dalton Trans 2009:1339-51. [PMID: 19462655 DOI: 10.1039/b815931a] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Lothar Weber
- Fakultät fur Chemie der Universität Bielefeld, Universitätsstrasse 25, 33615 Bielefeld, Germany.
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Brockhinke A, Letzgus M, Rinne S, Kohse-Höinghaus K. Energy Transfer in the d3Πg−a3Πu (0−0) Swan Bands of C2: Implications for Quantitative Measurements. J Phys Chem A 2006; 110:3028-35. [PMID: 16509624 DOI: 10.1021/jp055553g] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Energy transfer effects on dicarbon (C2) d3Pi(g) <-- a3Pi(u) laser-induced fluorescence (LIF) spectra in fuel-rich acetylene atmospheric-pressure flames have been studied using a combination of two different two-dimensional techniques. Measurements using a picosecond laser system in conjunction with a streak camera allowed determination of typical fluorescence lifetimes of levels in the d state and of population changes introduced by rotational energy transfer (RET) and by state-dependent quenching. Excitation-emission spectroscopy yielded two-dimensional maps containing all excitation and all emission spectra in the spectral ranges between 19 340 and 20 150 cm(-1) (excitation) and from 546 to 573 nm (emission) and allowed unambiguous assignment of all transitions in this spectral region. Our measurements show a comparatively long quenching lifetime (around 2 ns) and dominant effects of energy transfer on shape and intensity of the acquired spectra (90% of the fluorescence stems from levels populated by ET). A pronounced dependence of the total RET on the quantum number of the initially excited state is observed. Vibrational energy transfer (VET) is significantly weaker (only 5% contribution for excitation in the v' = 1 level). Implications for quantitative concentration measurements are discussed, and exemplary spatially resolved profiles in a well-characterized low-pressure propene flame are presented.
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Affiliation(s)
- A Brockhinke
- Physikalische Chemie 1, Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, Bielefeld D-33615, Germany
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Schocker A, Kohse-Höinghaus K, Brockhinke A. Quantitative determination of combustion intermediates with cavity ring-down spectroscopy: systematic study in propene flames near the soot-formation limit. Appl Opt 2005; 44:6660-72. [PMID: 16270555 DOI: 10.1364/ao.44.006660] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Cavity ring-down spectroscopy (CRDS) was applied in several fuel-rich, one-dimensional, premixed C3H6/O2/Ar flames at 50 mbars (37.5 torr) to measure absolute OH, HCO, and 1CH2 concentration as well as temperature as a function of stoichiometry. Although these flames near the sooting limit present a complex chemical environment, significant spectral interferences were found to be absent. Specific aspects of the CRDS technique for measurement of temperature and radical concentration profiles are discussed; and the results are analyzed in comparison with flame model simulations.
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Affiliation(s)
- Alexander Schocker
- Universität Bielefeld, Fakultät für Chemie, Physikalische Chemie I, Universitätsstrasse 25, D-33615 Bielefeld, Germany
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Brockhinke A, Lenhard U, Bülter A, Kohse-Höinghaus K. Energy transfer in the OH A2sigma+ state: the role of polarization and of multi-quantum energy transfer. Phys Chem Chem Phys 2005; 7:874-81. [PMID: 19791375 DOI: 10.1039/b415637d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Energy transfer in the excited state of molecules including quenching, rotational and vibrational energy transfer, and polarization scrambling is one of the major factors which limit the accuracy of laser-induced fluorescence (LIF) measurements. In this contribution, we present time-, wavelength-, and polarization-resolved spectra of OH in a stoichiometric H2/air flame at atmospheric pressure. Emphasis is placed on the investigation of the role of polarization effects and of multi-quantum vibrational energy transfer on fluorescence spectra originating from the OH A2sigma+ state. Results are compared to simulations using a rate-equation model (LASKIN) developed in our group.
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Affiliation(s)
- Andreas Brockhinke
- Physikalische Chemie I, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany.
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28
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Siemeling U, Bausch K, Fink H, Bruhn C, Baldus M, Angerstein B, Plessow R, Brockhinke A. Platinum(ii) 1,10-phenanthroline complexes of acetylides containing redox-active groups. Dalton Trans 2005:2365-74. [PMID: 15995744 DOI: 10.1039/b503794h] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The new diimine ligand 3,8-di-n-pentyl-4,7-di(phenylethynyl)-1,10-phenanthroline (1) was used for the synthesis of a range of Pt(II) complexes, viz.[Pt(1)Cl2], [Pt(1)(C triple bond C-Ph)2], [Pt(1)(C triple bond C-Fc)2] and [Pt(1)(C triple bond C-p-C6H4-C triple bond C-Fc)2](Fc = ferrocenyl). Crystal structure analyses were performed for [Pt(1)Cl2] and [Pt(1)(C triple bond C-Ph)2] and revealed that the di(acetylide)pi-tweezer of the latter binds a molecule of chloroform through C-H...pi hydrogen bonds. The redox and optical properties of 1 and its complexes were investigated by (spectro-)electrochemistry, UV-Vis and luminescence spectroscopy, and an energy level diagram was derived for [Pt(1)(C triple bond C-Fc)2] and related compounds on the basis of the data collected. The ferrocenyl-substituted Pt(II) complexes are donor-sensitiser assemblies. Intramolecular quenching of the photoexcited Pt(II) diimine unit leads to very short luminescence lifetimes for [Pt(1)(C triple bond C-p-C(6)H(4)-C triple bond C-Fc)2](2 ns) and [Pt(1)(C triple bond C-Fc)2](0.3 ns), as opposed to [Pt(1)(C triple bond C-Ph)2](0.7 micros). Excimer formation has been observed for [Pt(1)(C triple bond C-Ph)(2)] at room temperature in dichloromethane and at low temperatures in frozen glassy dichloromethane and 2-methyltetrahydrofuran solution, but not in the solid state.
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Affiliation(s)
- Ulrich Siemeling
- Institute of Chemistry and Centre for Interdisciplinary Nanostructure Science and Technology, University of Kassel, D-34109 Kassel, Germany.
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Lotte K, Plessow R, Brockhinke A. Static and time-resolved fluorescence investigations of tryptophan analogues--a solvent study. Photochem Photobiol Sci 2004; 3:348-59. [PMID: 15052363 DOI: 10.1039/b312436c] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The fluorescence properties of tryptophan, polytryptophan and seven of its analogues (7-azatryptophan, 5-hydroxytryptophan, 5-methoxytryptophan, 5-fluorotryptophan, 5-methyltryptophan, 5-bromotryptophan, and 6-fluorotryptophan) are studied using two novel fluorescence spectroscopic techniques for a wide range of solvent polarities. Two-dimensional mapping of all emission and all fluorescence spectra using excitation-emission spectroscopy (EES) has been used to determine quantum yields, positions of emission maxima, full widths at half maximum (FWHMs) as well as Stokes' shifts. Additionally, fluorescence lifetimes obtained from time-resolved experiments using a picosecond laser system are presented and compared with the data acquired from the static setup. This systematic study of the fluorescence characteristics is a prerequisite to assess the potential of these analogues to act as structure-conserving substitutes for tryptophan in protein fluorescence experiments. The potential of these analogues, to act as probes for the local environment, and allow estimation of the polarity in the vicinity of the fluorophore and its exposure to the solvent, is discussed.
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Affiliation(s)
- Kirsten Lotte
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstrasse 25, D-33615 Bielefeld, Germany
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Hagenstein MC, Mussgnug JH, Lotte K, Plessow R, Brockhinke A, Kruse O, Sewald N. Affinity-Based Tagging of Protein Families with Reversible Inhibitors: A Concept for Functional Proteomics. Angew Chem Int Ed Engl 2003; 42:5635-8. [PMID: 14639736 DOI: 10.1002/anie.200352084] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Miriam C Hagenstein
- Department of Chemistry, Organic and Bioorganic Chemistry, University of Bielefeld, Universitätsstrasse 25, 33 615 Bielefeld, Germany
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Hagenstein MC, Mussgnug JH, Lotte K, Plessow R, Brockhinke A, Kruse O, Sewald N. Affinitätsbasierte Markierung von Proteinfamilien mit reversiblen Inhibitoren– ein Konzept für die funktionelle Proteomik. Angew Chem Int Ed Engl 2003. [DOI: 10.1002/ange.200352084] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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32
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König J, Lotte K, Plessow R, Brockhinke A, Baier M, Dietz KJ. Reaction mechanism of plant 2-Cys peroxiredoxin. Role of the C terminus and the quaternary structure. J Biol Chem 2003; 278:24409-20. [PMID: 12702727 DOI: 10.1074/jbc.m301145200] [Citation(s) in RCA: 136] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Barley 2-cysteine peroxiredoxin (2-Cys Prx) was analyzed for peroxide reduction, quaternary structure, thylakoid attachment, and function as well as in vivo occurrence of the inactivated form, with emphasis on the role of specific amino acid residues. Data presented show the following. 1) 2-Cys Prx has a broad substrate specificity and reduces even complex lipid peroxides such as phosphatidylcholine dilineoyl hydroperoxide, although at low rates. 2) 2-Cys Prx partly becomes irreversibly oxidized by peroxide substrates during the catalytic cycle in a concentration-dependent manner, particularly by bulky hydroperoxides. 3) Using dithiothreitol and thioredoxin (Trx) as reductants, amino acids were identified that are important for peroxide reduction (Cys64, Arg140, and Arg163), regeneration by Trx (Cys185), and conformation changes from dimer to oligomer (Thr66, Trp99, and Trp189). 4) Oligomerization decreased the rate of Trx-dependent peroxide detoxification. 5) Comparison of PrxWT, W99L, and W189L using static and time-resolved LIF techniques demonstrated the contributions of the tryptophan residues and yielded information about their local environment. Data indicated protein dynamics in the catalytic site and the carboxyl terminus during the reduction-oxidation cycle. 6) Reduced and inactivated barley 2-Cys Prx oligomerized and attached to the thylakoid membrane in isolated chloroplasts. The in vivo relevance of inactivation was shown in leaves subjected to cold and wilting stress and during senescence. Based on these results, it is hypothesized that in addition to its function in peroxide detoxification, 2-Cys Prx may play a role as a structural redox sensor in chloroplasts.
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Affiliation(s)
- Janine König
- Biochemistry and Physiology of Plants, University of Bielefeld, Germany
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33
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Siemeling U, Vor der Brüggen J, Vorfeld U, Neumann B, Stammler A, Stammler HG, Brockhinke A, Plessow R, Zanello P, Laschi F, Fabrizi de Biani F, Fontani M, Steenken S, Stapper M, Gurzadyan G. Ferrocenyl-functionalised terpyridines and their transition-metal complexes: syntheses, structures and spectroscopic and electrochemical properties. Chemistry 2003; 9:2819-33. [PMID: 12866548 DOI: 10.1002/chem.200204412] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Terpyridine ligands of the type Fc'-X-tpy (Fc'=ferrocenyl or octamethylferrocenyl, X=rigid spacer, tpy'=4'-substituted 2,2':6',2''-terpyridine) were prepared, crystallographically characterised and used for the synthesis of di- and trinuclear bis(terpyridine) complexes of RuII, FeII and ZnII. Donor-sensitiser dyads and triads based on RuII were thoroughly investigated by (spectro)electrochemistry, UV/Vis, transient absorption and luminescence spectroscopy, and an energy level scheme was derived on the basis of the data collected. Intramolecular quenching of the photoexcited RuII complexes by the redox-active Fc' groups can occur reductively and by energy transfer. Both the redox potential of the donor Fc' and the nature of the spacer X have a decisive influence on excited-state lifetimes and emission properties of the complexes. Some of the compounds show room-temperature luminescence, which is unprecedented for ferrocenyl-functionalised compounds of this kind.
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Brockhinke A, Daily JW, Miller JC. Laser applications to chemical and environmental analysis: introduction to the feature issue. Appl Opt 2003; 42:2019-2020. [PMID: 12716141 DOI: 10.1364/ao.42.002019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This issue of Applied Optics features 14 papers that describe recent advances of laser techniques, including instrumentation, application in combustion research, and detection of pollutants. Most of these contributions were presented at the Eighth Optical Society of America Topical Meeting on Laser Applications to Chemical and Environmental Analysis (8th LACEA), held in Boulder, Colorado, 7-10 February, 2002.
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Affiliation(s)
- Andreas Brockhinke
- Physikalische Chemie I, Universität Bielefeld, Universitätsstrasse 25, D-33615, Bielefeld, Germany.
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35
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Brockhinke A, Plessow R, Kohse-Höinghaus K, Herrmann C. Structural changes in the Ras protein revealed by fluorescence spectroscopy. Phys Chem Chem Phys 2003. [DOI: 10.1039/b303262k] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Abstract
Laser induced fluorescence (LIF) of OH (A 2 sigma +) is measured in several atmospheric-pressure flames using a short-pulse laser system (80 ps duration) in conjunction with an intensified streak camera. The two-dimensional signal-detection technique allows one to simultaneously monitor rotational and vibrational relaxation as well as electronic quenching. Rotationally-resolved LIF spectra affected by energy transfer are compared with the results of a rate-equation model and are found to be in reasonably good agreement. It is shown that a significant contribution of fluorescence detected by broad-band techniques is due to levels populated by vibrational energy transfer (VET). Implications for picosecond LIF techniques for the time-resolved, quench-free detection of OH are discussed. A detailed analysis is presented for fluorescence spectra originating from levels populated by VET after excitation of states in the OH (A 2 sigma +, v' = 2) level.
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Affiliation(s)
- A Brockhinke
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefield, Germany.
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37
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Plessow R, Brockhinke A, Eimer W, Kohse-Höinghaus K. Intrinsic Time- and Wavelength-Resolved Fluorescence of Oligonucleotides: A Systematic Investigation Using a Novel Picosecond Laser Approach. J Phys Chem B 2000. [DOI: 10.1021/jp994132u] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Regina Plessow
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Andreas Brockhinke
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Wolfgang Eimer
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
| | - Katharina Kohse-Höinghaus
- Physikalische Chemie I, Fakultät für Chemie, Universität Bielefeld, Universitätsstr. 25, D-33615 Bielefeld, Germany
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Brockhinke A, Kohse-Höinghaus K, Andresen P. Double-pulse one-dimensional Raman and Rayleigh measurements for the detection of temporal and spatial structures in a turbulent H(2)-air diffusion flame. Opt Lett 1996; 21:2029-2031. [PMID: 19881882 DOI: 10.1364/ol.21.002029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A novel spectroscopic technique for the observation of the temporal development of small spatial structures of temperature and major-species mole fractions in turbulent f lames has been developed. It uses two independent lasers and linewise, single-pulse detection systems for Raman-Rayleigh-scattered light. With this technique, all major-species concentrations, temperature, and positions of vortices and f lame fronts, combined with scalar dissipation in two directions or heat release, can be measured, for the first time to our knowledge, as a result of one pair of laser pulses separated either in space or time. This yields, to our knowledge, the highest number of correlated quantities that have been obtained in probing turbulent f lames of simple chemistry.
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Brockhinke A, Andresen P, Kohse-Höinghaus K. Contribution to the analysis of temporal and spatial structures near the lift-off region of a turbulent hydrogen diffusion flame. ACTA ACUST UNITED AC 1996. [DOI: 10.1016/s0082-0784(96)80212-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Drescher M, Brockhinke A, Böwering N, Heinzmann U, Lefebvre‐Brion H. Rotationally resolved single‐photon ionization of HCl and DCl. J Chem Phys 1993. [DOI: 10.1063/1.465245] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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