Thèses : « Tiem Resolved Spectroscopy »

1

Ekvall, Karin. « Time resolved laser spectroscopy ». Doctoral thesis, KTH, Physics, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3063.

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2

Moore, B. D. « Time-resolved infrared spectroscopy ». Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332449.

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3

Snow, Paul Alistair. « Time-resolved spectroscopy of GaSb ». Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308681.

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4

Camus, Enrique Castro. « Polarisation resolved terahertz time domain spectroscopy ». Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.441048.

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5

Hess, Stefan. « Time-resolved spectroscopy of gallium nitride ». Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301575.

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6

Bregy, Harald. « Time-resolved infrared spectroscopy of photoswitchable thioxopeptides / ». [S.l.] : [s.n.], 2009. http://opac.nebis.ch/cgi-bin/showAbstract.pl?sys=000286596.

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7

Moore, John Neville. « Time resolved spectroscopy of water-soluble anthraquinones ». Thesis, Imperial College London, 1986. http://hdl.handle.net/10044/1/38109.

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8

Dunkelberger, Adam David. « Time-resolved electronic spectroscopy of 2,2'-bisindene ». Connect to resource, 2007. http://hdl.handle.net/1811/28440.

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Thesis (Honors)--Ohio State University, 2007.
Title from first page of PDF file. Document formatted into pages: contains 35 p.; also includes graphics. Includes bibliographical references (p.35). Available online via Ohio State University's Knowledge Bank.

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9

Tatham, Martin Christopher. « Time resolved Raman spectroscopy of semiconductor structures ». Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305429.

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10

Grills, David C. « Time-resolved infrared spectroscopy in Supercritical fluids ». Thesis, University of Nottingham, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285677.

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11

Clark, Ian P. « Time-resolved infrared spectroscopy of organometallic states ». Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363942.

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12

Khajeh, Maryam. « Kinetic measurements using time-resolved NMR spectroscopy ». Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/kinetic-measurements-using-timeresolved-nmr-spectroscopy(aae85bb3-de19-450a-96ab-50e2dfd89da7).html.

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Many thousands of pounds are spent every year by pharmaceutical companies on understanding the mechanisms and kinetics of chemical reactions involved in drug discovery and production. NMR spectroscopy is often at the core of these studies as it is a powerful, non-destructive method for structure elucidation. As such investigations can be time-consuming and cost-inefficient, AstraZeneca, the project sponsor, is interested in more efficient methods for studying the kinetics of pharmaceutical reactions. In this work a number of different techniques have been devised, studied, and implemented to study the kinetics of chemical reactions by time-resolved NMR spectroscopy, in which every species in a reaction can be monitored simultaneously. These novel techniques allow the study of reactions which are difficult or impossible to study by conventional NMR methods (such as heterogeneous reactions), or which are complicated by having overlapping signals. It is possible to monitor the kinetics of a reaction very simply by acquiring a series of 1H spectra, and obtaining the integrals of the signals by least squares fitting. This technique has been used for kinetic studies of static and on-flow reactions. In the static systems the reaction mixture was placed in the normal NMR tube in the magnet, while in the flow system the reaction mixture was placed outside of the magnet, and the solution flowed through an NMR tube placed in the magnet. The novel flow system designed, constructed and tested here has been used for kinetic studies of illustrative homogeneous and heterogeneous reactions, and is suitable for use in a wide range of NMR instrumentation. Kinetic studies have also been carried out by acquiring a series of DOSY datasets, analysing the results using the multi-way method PARAFAC (PARAllel FACtor analysis). A series of DOSY datasets contains multivariate information on spectrum, time evolution and diffusion. Without providing any predetermined model, the data can be decomposed by PARAFAC to yield the spectrum, kinetics, and diffusion profiles for each of the components. It has also been shown that PARAFAC is remarkably robust to low signal-to-noise ratio data, significantly below the level at which conventional methods would fail.

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13

Brown, Alan Jeffrey. « Time resolved evanescent wave induced fluorescence spectroscopy ». Thesis, Imperial College London, 1990. http://hdl.handle.net/10044/1/47790.

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14

George, Michael W. « Time-resolved infrared spectroscopy of reaction intermediates ». Thesis, University of Nottingham, 1990. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.591102.

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15

Graf, Urs. « Characterization of molecules by time-resolved fluorescence spectroscopy / ». [S.l.] : [s.n.], 1994. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10746.

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16

Kurt, Mustafa. « Time Resolved Spectroscopy Of Laser Induced Air Plasma ». Phd thesis, METU, 2007. http://etd.lib.metu.edu.tr/upload/12608985/index.pdf.

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The laser beam interaction with matter and the plasma generation have been studied for many years. In some applications what is really important is to understand the composition and the temporal evolution of the species in the interested medium. In this thesis, time resolved optical spectroscopy was employed to understand the evolution of the plasma which is produced by interaction of Infrared (1.064 µ
m) laser beam with air. In this thesis, a new technique is suggested to analyze the time evolution of laser induced breakdown spectroscopy. The suggested method and the instrumentation of the setup are tested with a single gas (He). After the tests, we analyzed time sequence spectra of Laser Induced Air Breakdown. The suggested method is based on triggering the laser and the spectrometer at different time and applying the spectrometer trigger time by adding the time delay (&
#916
t) between them by using the pulse generator. The results show that the decay rates are slowing down microseconds after the excitation of the plasma. The results of the time-resolved measurements of the line spectra show that different component of the air has different decay rate, and lifetime. The lifetime of helium is 20 µ
s, and the decay start 5 µ
s after the initiation of plasma. Air has 12 µ
s lifetime, and the decay start 3 µ
s after the initiation of the plasma. Also, the decay rate and the lifetime depend on the state. We also calculate Doppler velocity for different component and different emission states. Doppler velocities show that the component which has great mass has small velocity, the component which has small mass has high velocity.

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17

Jina, Omar S. « Probing reaction mechanisms with time resolved infrared spectroscopy ». Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252009.

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18

Virrels, Ian G. « Fast time-resolved infrared spectroscopy of reactive intermediates ». Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387857.

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19

Lewis, Thomas Robert. « Time-resolved absorption spectroscopy applied to tropospheric chemistry ». Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/18122/.

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A Time-Resolved UV-Vis Absorption Spectrometer (TRUVAS) has been constructed with the ability to record time-resolved absorption spectra between ~250-800 nm, with a maximum time-resolution of 0.78 ms. The rate of reaction of the C1 Criegee Intermediate (formaldehyde oxide) with water vapour has been studied. The removal rate constant shows a quadratic dependence on [H2O], implying reaction with the water dimer, (H2O)2. The removal rate of the Criegee intermediate via. reaction with the water dimer ((H2O)2) was discovered to be 4.0 ± 1.2 × 10−12 cm3 molecule−1 s−1, and sufficiently fast to dominate the species’ removal in the troposphere. This result was published in PCCP3. The primary motivation for building the TRUVAS instrument was to measure the absorption cross-sections of isoprene-derived peroxy radicals in the actinic region, with a view to calculating the total atmospheric photolysis rates. The total atmospheric photolysis rates of the isoprene, 2,3-dimethylbutadiene and butadiene hydroxyperoxy (HP) radicals were calculated at noon in Borneo, and were found to be 1.27, 1.81 and 1.01 × 10-3 s-1 respectively. The absorption spectra of ethylene, but-2-ene and 2,3-dimethylbut-2-ene (TetraMethyl Ethylene – TME) HP radicals were measured. The measured absorption spectra show a marked broadening effect, with the Gaussian width increasing 11% from ethylene to but-2-ene HP radical absorption spectrum, and 26% to the TME HP radical, which translate to atmospheric photolysis rates of 0.552, 1.21 and 1.68 × 10-3 s-1. The absorption spectra of the methyl, tertiary-butyl and cyclohexyl peroxy radicals are presented. The methyl peroxy absorption spectrum measured in this study largely agree with the numerous existing studies. Atmospheric photolysis of methyl peroxy radicals comprises around 1% of the species’ removal in the marine boundary layer.

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20

Williams, Leah Ruby. « Femtosecond time-resolved spectroscopy of organic molecular crystals ». Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/14589.

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21

Dakovski, Georgi L. « TIME-RESOLVED TERAHERTZ SPECTROSCOPY OF SEMICONDUCTOR QUANTUM DOTS ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=case1192470456.

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22

Neupane, Chandra Prasad Neupane. « Time Resolved Optical Spectroscopy of Colloidal PbS Nanosheets ». Bowling Green State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1530805332385177.

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23

Murphy, Thomas S. « Time-resolved spectroscopic studies of reactive intermediates ». Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/31288/.

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Chapter 1. Introduction. An introduction to the detection of reactive intermediates by various spectroscopic techniques is given, as well as a brief introduction to perfluorinated solvents, which are used throughout the work presented in Chapters 2 to 4. Chapter 2. Time-Resolved Studies of Spin-Forbidden Reactions of Transition Metal Carbonyls with Weak Ligands. The photolysis of a series of first-row transition metal carbonyl compounds which have been previously reported to form 16-electron coordinatively unsaturated intermediates was examined in a series of perfluorinated solvents using TRMPS (time-resolved multiple probe spectroscopy) and TRIR (time-resolved infrared) spectroscopy. In the case of Fe(CO)5, CpMn(CO)3, (MeCp)Mn(CO)3 and CpV(CO)4, the rate of reaction of the 16-electron intermediate with the perfluorinated solvent was found to be slower than that previously reported for weakly coordinating solvents (e.g. alkanes). Addition of cyclopentane, CO2, Xe and C2H6 to a solution of CpMn(CO)3 in perfluoro(methylcyclohexane) was shown to change the rate of this spin-forbidden reaction, as well as the (CO) band positions of the resulting 1CpMn(CO)2X (X = solvent or dopant) complex. Other perfluorinated materials (perfluoro(hexanes) and perfluoro(triethylamine)) are also shown to allow formation of such weakly-coordinated alkane and noble gas complexes in room-temperature liquid solution. Chapter 3. Further Time-Resolved Studies of Alkane and Noble Gas Complexes in Room Temperature Perfluoroalkane Solutions. The photochemistry of various model transition metal compounds in perfluoroalkane solutions was examined with TRMPS and TRIR spectroscopy. 266 nm photolysis of CpRe(CO)3, Cp*Re(CO)3 and CpRe(CO)2(N2) in perfluoro(methylcyclohexane) solution was found to result in the formation of two distinct dicarbonyl species of the form CpRe(CO)2X, the first of which decay completely on the nanosecond timescale to form the second. The rate of formation, rate of decay and (CO) band positions of this second dicarbonyl species were found to be dependent on the nature of the the solvents or dopants including Xe or cyclopentane present in solution. Similar results were observed for complexes of the form M(CO)6 (M = Cr, Mo, W). DFT calculations were used in conjunction with spectroscopic studies to attempt to confirm the structure of the initially formed species following photolysis of CpRe(CO)3 and M(CO)6 in PFMCH solution. Good agreement was observed between the calculated (CO) band positions of coordinatively unsaturated species and the unknown initially formed CO loss species. Doping of CH4 or C2H6 into a solution of CpRe(CO)3 or Cp*Re(CO)3 resulted in observation of a C-H activated alkyl hydride complex, with the amount of observed C-H activation vaying in the order: CpRe(CO)3 with ethane < Cp*Re(CO)3 with ethane < CpRe(CO)3 with methane < Cp*Re(CO)3 with methane. Photolysis of CpRh(CO)2 in perfluoroalkane solvents was shown to lead to formation of a monocarbonyl solvent complex, followed by the dimeric species Cp2Rh2(CO)3, as well as another species, very tentatively assigned to a C-F activated oxidative addition product. Addition of Xe to the above solution was shown to slow formation of the dimeric species, with no evidence of C-F activation observed, indicating formation of CpRh(CO)Xe in room temperature solution. Chapter 4. Time-Resolved Spectroscopic Studies of Organometallic Triethylsilane Complexes. TRMPS studies of CpMn(CO)3, CpRe(CO)3 and Cp*Re(CO)3 were undertaken in neat HSiEt3 solvent. Photolysis of CpMn(CO)3 resulted in initial formation of 3CpMn(CO)2, following by both direct and indirect formation of the Si-H activated speciesin both cases. Photolysis ofW(CO)6 was found to result in initial formation of the ethyl-boundW(CO)5(EtSiHEt2), which interconverted to form the Si-H-bound speciesW(CO)5(H−SiEt3). Preliminary time-resolved x-ray absorption fine structure spectroscopic studies are also presented. Photolysis of W(CO)6 and CpRe(CO)3 in neat HSiEt3 was observed to cause subtle changes in the absorption edge compared to ground state XAFS spectra, indicating possible formation of transient species in both cases. Chapter 5. Experimental. The experimental techniques utilised in this Thesis are described.

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Jerebtsov, Serguei Nikolaevich. « Femtosecond time-resolved spectroscopy of coherent oscillations in nanomaterials ». [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-1358.

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25

Walser, Andreas Markus. « Time-resolved four-wave mixing spectroscopy of gaseous formaldehyde / ». Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18044.

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Paski, Edgar Francis. « Inorganic powder analysis by time-wavelength resolved luminescence spectroscopy ». Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29045.

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An investigation into the potential of time-wavelength resolved luminescence spectroscopy for the analysis of inorganic powders was performed. A time-wavelength resolved luminescence spectrometer consisting of an excimer laser, scanning monochromator, and gated integrator was constructed. The spectrometer had wavelength coverage from 265 nm to 800 nm, it was capable of measuring lifetimes between 100 ns and 500 ms. Sample excitation was done at 193 nm and 248 nm. A luminescence system model of first order decay in the time domain and a Gaussian function for the emission band was assumed. The time-wavelength resolved luminescence spectrum was described by the parameters: lifetime, peak maxima, peak halfwidth, and intensity factor. Parameter estimation was done with an algorithm employing a linear algebra construct and simplex optimization. The algorithm's performance on highly overlapped spectra was evaluated. For two component mixtures having a 1 % RSD noise level, overlaps greater than 0.3 halfwidths in the spectral domain and lifetime ratios greater than 1:1.3 were resolved with all parameter estimates having an error of less than ±2%. The luminescence spectra of CaMo0₄, SrMo0₄, BaMo0₄, ZnMoO₄, CdMo0₄, PbMoO₄, CaWO₄, SrW0₄, BaWO₄, ZnWO₄, CdW0₄ and PbWO₄ consisted of broad featureless bands showing simple exponential decay. Mixed crystals of Ca(MOxW₁-x)O₄ and Sr(MOxW₁-x)0₄ were examined. Tungstate emission was quenched by molybdate, the molybdate emission dominated when x was greater than 0.15. The tungstate lifetime was found to be proportional to molybdate concentration. The luminescence spectra of CaZrO₃, SrZr O₃, BaZr O₃ CaHfO₃ SrHfO₃, BaHfO₃, CaO, SrO, and BaO as pure compounds and doped with T1, Pb, Sb, and Bi were studied. The pure zirconates and hafnates showed short lived (<100 ns) luminescence with 248 not excitation; no readily discernible luminescence was observed with 193 nm excitation. Doped compounds tended to show luminescence characteristic of the dopant ion.
Science, Faculty of
Chemistry, Department of
Graduate

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27

Stevens, Christopher John. « Time-resolved spectroscopy of excitons in II-VI heterostructures ». Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308909.

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28

Vilmart, Gautier. « Modification of solids with ultrashort pulses : time-resolved spectroscopy ». Thesis, KTH, Tillämpad fysik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-152472.

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29

Aurelio, I. Andrew. « Laser-induced breakdown spectroscopy as a diagnostic tool for coal fines ». Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4404.

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Thesis (M.S.)--West Virginia University, 2005.
Title from document title page. Document formatted into pages; contains xii, 96 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 56-59).

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30

Calladine, James Andrew. « Time-resolved infrared spectroscopic studies of reaction intermediates ». Thesis, University of Nottingham, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.537693.

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31

Cowan, Alexander J. « Time-resolved infrared spectroscopic studies of reaction mechanisms ». Thesis, University of Nottingham, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444615.

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32

Šiffalovič, Peter. « Femtosecond time resolved photoelectron spectroscopy in the extreme ultraviolet region ». [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=964973502.

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33

Hutzler, Daniel [Verfasser]. « Time-Resolved Infrared Spectroscopy on Hydrogen Bonded Systems / Daniel Hutzler ». München : Verlag Dr. Hut, 2017. http://d-nb.info/1149579110/34.

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34

Bäckström, Erik. « Time-Resolved Spectroscopy and Intensity Measurements of Singly Charged Ions ». Doctoral thesis, Stockholms universitet, Fysikum, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-113503.

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This thesis is mainly concerned with investigations of spontaneous radiatively decaying states in both negative and positive singly charged ions. When possible, the measured lifetime of the state has been combined with branching fractions in order to derive the absolute transition probability (A-value) between different quantum states. The radiative transition probability between two quantum states is a fundamental atomic property. Knowledge of this property can be used as a diagnostic tool in, for example, abundance and temperature determinations with applications in many fields, e.g. astronomy, plasma physics, atomic physics etc. The focus of the experiments has been on lifetime measurements of long-lived metastable states. Lifetimes of long-lived metastable states are interesting in both theoretical aspects as well as the challenge it poses to the experimentalist. To perform such experiments, impact from the surrounding environment on the stored ions has to be kept to a minimum for extended periods of time. The metastable lifetimes presented here have been measured with time-resolved laser spectroscopic techniques in two different types of ion storage rings. One of them is a new type of unique cryogenically cooled storage ring made of purely electrostatic ion optical elements. As is demonstrated in this thesis, this device opens up a completely new time domain where lifetime measurements now can be performed. In addition, this thesis includes a discussion and preliminary studies of weak interactions otherwise limited by magnetic fields and/or thermal radiation from the environment. When available, the results have been compared to previous measurements and theoretical calculations which enables an evaluation of different methods and theoretical models.

At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 6: Accepted.

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35

Colley, Christopher S. « Time-resolved infrared spectroscopy of organic and biological transient species ». Thesis, Nottingham Trent University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367318.

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36

Fisher, Brent R. « Time resolved fluorescence of CdSe nanocrystals using single molecule spectroscopy ». Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33649.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2005.
Vita.
Includes bibliographical references.
A wide variety of spectroscopic studies of CdSe nanocrystals (NCs) are presented in this thesis, all studying some aspect of the temporal evolution of NC fluorescence tinder different conditions. In particular the methods of single molecule spectroscopy are used in many experiments allowing the behavior of individual NCs to be resolved from the blurring effect of averaging over the ensemble. Studies of the excited state lifetime of band edge fluorescence from single NCs reveal multiexponential relaxation dynamics that stem from fluctuations of non-radiative decay rates for the band edge exciton. Analysis of these fluctuations allows us to extract single exponential dynamics by sampling only "maximum-intensity" photons, and we find that this single exponential decay is remarkably uniform across a wide variety of NC samples and sizes. We also investigate luminescence from multiexciton (e.g. biexciton and triexciton) states of nanocrystals at both the ensemble and single NC level.
(cont.) Energy splittings, size and temperature dependencies, quantum yields and lifetimes of multiexciton states are measured and discussed. We show for the first time direct resolution of biexciton emission from single exciton emission using two different techniques, fluorescence line narrowing and single NC spectroscopy. We also study the non-classical light emission properties of single NCs and show how multiexciton emission leads to radiative quantum cascades of single photons in the emission of a single NC. Time resolved studies of fluorescence from NCs in solution environments conclude the thesis. The relationship between lifetime and quantum yield for non-homogeneous ensembles like NCs is studied in chapter 8. We show that a sub-population of non-luminescent nanocrystals can reduce the quantum yield of an ensemble of NCs even though the measured lifetime stays constant. A study of NCs in solution fluorescence correlation spectroscopy (FCS) is presented last. We find that FCS is a capable tool for distinguishing small differences in hydrodynamic radius of NCs in solution. We also find that blinking of NCs may have a significant impact on these FCS measurements.
(cont.) An appendix to this thesis presents a general summary the lifetime of various samples CdSe and CdTe NCs.
by Brent R. Fisher.
Ph.D.

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37

El-Zohry, Ahmed M. « Exploring Organic Dyes for Grätzel Cells Using Time-Resolved Spectroscopy ». Doctoral thesis, Uppsala universitet, Institutionen för kemi - Ångström, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-263143.

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Grätzel cells or Dye-Sensitized Solar Cells (DSSCs) are considered one of the most promising methods to convert the sun's energy into electricity due to their low cost and simple technology of production. The Grätzel cell is based on a photosensitizer adsorbed on a low band gap semiconductor. The photosensitizer can be a metal complex or an organic dye. Organic dyes can be produced on a large scale resulting in cheaper dyes than complexes based on rare elements. However, the performance of Grätzel cells based on metal-free, organic dyes is not high enough yet. The dye's performance depends primarily on the electron dynamics. The electron dynamics in Grätzel cells includes electron injection, recombination, and regeneration. Different deactivation processes affect the electron dynamics and the cells’ performance. In this thesis, the electron dynamics was explored by various time-resolved spectroscopic techniques, namely time-correlated single photon counting, streak camera, and femtosecond transient absorption. Using these techniques, new deactivation processes for organic dyes used in DSSCs were uncovered. These processes include photoisomerization, and quenching through complexation with the electrolyte. These deactivation processes affect the performance of organic dyes in Grätzel cells, and should be avoided. For instance, the photoisomerization can compete with the electron injection and produce isomers with unknown performance. Photoisomerization as a general phenomenon in DSSC dyes has not been shown before, but is shown to occur in several organic dyes, among them D149, D102, L0 and L0Br. In addition, D149 forms ground state complexes with the standard iodide/triiodide electrolyte, which directly affect the electron dynamics on TiO2. Also, new dyes were designed with the aim of using ferrocene(s) as intramolecular regenerators, and their dynamics was studied by transient absorption. This thesis provides deeper insights into some deactivation processes of organic dyes used in DSSCs. New rules for the design of organic dyes, based on these insights, can further improve the efficiency of DSSCs.

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O'Malley, Rachel Louise. « Time resolved x-ray absorption spectroscopy studies of electrogenerated species ». Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616121.

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39

Rattray, P. « Pulsed flow and time-resolved dielectric spectroscopy of electrorheological fluids ». Thesis, Cranfield University, 1994. http://dspace.lib.cranfield.ac.uk/handle/1826/10508.

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Research has been undertaken into the dielectric and rheological properties of electrorheological (ER) fluids. The fluids studied were based on acene-quinone radical polymers made within the department dispersed in silicone oil. A commercial poly(1ithium methacrylate) dispersion was also examined. As a means of probing the underlying mechanisms of the E phenomenon, the permittivity of the fluids was measured from 12 Hz to 100 kHz under both static and dynamic conditions. Results indicated that a interfacial polarization process was taking place. A series of visual observations were made of fluids under different fielding patterns. A series of photographs were taken that illustrated the structure formation with elapsed time in a dilute fluid. Also photographs were taken of the final structure formed under different field conditions. .. To perform permittivity measurements of the fluid when a electric field was applied, a high voltage biasing unit was designed, built and proved. This allowed the application of a continuous DC electric field of up to 3 kVmm" and the permittivity to be measured from 150 H t 100 kl-Iz. Through a series of experiments it was found that the low frequency permittivity increased with increasing electric field. This result was partially explained by the Sillars model. The fluids were also subjected to shear rates from 1500 to 60 s". Flow modified permittivity resonances were found at the predicted frequencies. However, the resonant frequency did not move significantly under the application of a electric field. The structuring process was time resolved and a model was made to predict the sealing of the characteristic structuring time. The rheological response of the fluids when subjected t pulsed DC fields was examined and found to be dominated by a instrumentational effect. Al experimental procedures are given along with a comprehensive examination of the equipment. The results are discussed as they occur in terms of the models appropriate to that particular event.

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40

McCleese, Christopher. « Femtosecond Time-Resolved Spectroscopy Studies of Interfacial Charge Separation Processes ». Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case149182204612303.

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41

Ross, Stuart K. « Time resolved spectroscopy using the shock tube characterisation and calibration ». Thesis, University of Aberdeen, 1995. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU539033.

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The main objective of this work was the development of the existing shock tube system so that it could be used for kinetic investigations. As a result of the many modifications and alterations to the shock tube, and thorough and successful characterisation experiments, the shock tube is now considered to be suitable for the study of high temperature gas phase reactions. One of the important features of the characterisation experiments was the dependency of several shock parameters (P2(expt), P5(expt), and Mr) on the initial test gas pressure in the shock tube. Shock parameters have been determined which take into account non-ideal behaviour such as side wall boundary layer formation. The atomic resonance absorption spectroscopy (ARAS) detection technique was only installed during the latter stages of this work, and due to time restrictions is not yet fully operational. When this is achieved the shock tube at Aberdeen will be the only shock tube in the U.K. where time resolved, gas phase reactions, can be kinetically investigated. Results from Brookhaven National Laboratory, New York, are presented where a similar shock tube - ARAS system was calibrated for atomic oxygen. Nitrous oxide (N2O) was used as a clean source of O atoms, and the bimolecular rate expression for the reaction: N2O + M N2 + O + M. over the temperature range 1266 T(K) 2311 was determined to be: k (cm3molecule-1s-1) = (1.220.19)x10-9 exp (-57861600 cal/RT). This rate expression is in good agreement with literature values.

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Peng, Lawrence Weimin Zewail Ahmed H. Zewail Ahmed H. « Reactions in small clusters studied by time-resolved laser spectroscopy / ». Diss., Pasadena, Calif. : California Institute of Technology, 1991. http://resolver.caltech.edu/CaltechETD:etd-04042008-130407.

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Dyer, Joanne. « Designing infrared probes of DNA based on rhenium tricarbonyl DPPZ complexes ». Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289455.

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Ray, Jayashree. « Time-resolved spectroscopic studies of bacterial heme-copper oxidases / ». Diss., Digital Dissertations Database. Restricted to UC campuses, 2006. http://uclibs.org/PID/11984.

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朱麗敏 et Lai-man Chu. « Time-resolved spectroscopic investigation of chloroaniline and oxetanerelated compounds ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B39557455.

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An, Huiying, et 安慧颖. « Time-resolved spectroscopic studies of selected photoremovable protecting groups ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B44891672.

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Buchner, Franziska [Verfasser]. « Time-resolved photoelectron spectroscopy of DNA molecules in solution / Franziska Buchner ». Berlin : Freie Universität Berlin, 2015. http://d-nb.info/1071843478/34.

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Jawurek, Michael [Verfasser]. « Protein-membrane interactions investigated with time-resolved FTIR spectroscopy / Michael Jawurek ». Konstanz : Bibliothek der Universität Konstanz, 2017. http://d-nb.info/1151957127/34.

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Ciesla, Craig Michael. « Time-resolved spectroscopy of narrow gap semiconductors with free-electron lasers ». Thesis, Heriot-Watt University, 1997. http://hdl.handle.net/10399/648.

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Rooney, Denise. « Time-resolved raman spectroscopy and photolysis of transition metal carbene complexes ». Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334489.

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Thèses sur le sujet « Tiem Resolved Spectroscopy »

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