Carbon nanotubes (CNT) and graphene have been one of the noticeable research areas in science and technology. In recent years, the assembly of these carbon nanostructures is one of the most interesting topic to the scientific world due to its variety of applications from nano to macroscale. These bulk nanostructures to be applicable in shock absorbers, batteries, sensors, photodetectors, actuators, solar cells, fuel cells etc. The present work is motivated to study the detailed compressive behavior of three dimensional cellular assemblies of CNT and graphene. The CNT foams are synthesized by chemical vapor deposition method. It is interesting to study the compressive behavior of CNT foam in the presence external magnetic field applied perpendicular to CNT axis. The peak stress and energy absorption capability of CNT foam enhances by four and nearly two times in the presence of magnetic field as compared to the absence of the magnetic field. In the absence of magnetic field the deformation of CNT foam is obtained elastic, plateau and densification regions. Further CNT foam is loaded with iron oxide nanoparticles of diameter is ~ 40nm on the surface and detailed study of the compressive behavior of the foam by varying iron nanoparticles concentration. The peak stress and energy absorption capability of CNT foam initially decreases with increasing the intensity of the magnetic field, further increases the intensity of the magnetic field the maximum stress and energy absorption capability increases which is due to magnetic CNT and particles align in the direction of the magnetic field. CNT surfaces were further modified by fluid of different viscosities. The mechanical behavior of CNT foam filled with fluids of varying viscosities like 100%, 95% and 90% glycerol and silicone oil are 612, 237, 109 and 279 mPa-s respectively. The mechanical behavior of CNT foam depends on both the intensity of magnetic field and fluid viscosity. The non linear relation between peak stress of CNT and magnetic field intensity is σp(B, η) = σ0 ± α(B-B0) where σ0 is the peak stress at B = B0 , η is the fluid viscosity, parameter α depends on properties of the MR fluid and B0 is an optimum magnetic field for which peak stress is maximum or minimum depending on the fluid viscosity. Graphene is assembled into a three dimensional structure called graphene foam. The graphene foam is infiltrated with polymer and study the detailed compressive behavior of graphene foam and graphene foam/PDMS at different strains of 20, 40, 60 and 70%. The maximum stress and energy absorption capability of graphene foam/PDMS is six times higher than the graphene foam. Also the graphene foam/PDMS is highly stable and reversible for 100 cycles at strains of 30 and 50%. The mechanical behavior of CNT, graphene foam, CNT/PDMS and graphene foam/PDMS is compared. Among all the foams, graphene foam/PDMS has shown the highest elastic modulus as compared to other foams. This behavior can be attributed to the wrinkles formation during the growth of graphene and a coupling between PDMS and interfacial interactions of graphene foam. Therefore it suggests potential applications for dampers, cushions and electronic packaging. Furthermore, the interaction between nanoparticles and polymer in a novel architecture composed of PDMS and iron oxide nanoparticles is studied. The load bearing capacity of uniform composites enhanced by addition of nanoparticles, reaching to a maximum to 1.5 times of the PDMS upon addition of 5wt.% of nanoparticles, and then gradually decreased to 1/6th of PDMS upon addition of 20wt.% of nanoparticles. On the other hand, the load bearing capacity of architectured composites at high strains (≥40%) monotonically increased with addition of nanoparticles in the pillars.

Optically-transparent solids have a significant role in many emerging topics of fundamental and applied research, in areas related to Applied Optics and Photonics. In the functional devices based on them, the presence of ‘time-varying temperature fields’ critically limit their achievable performance, when used particularly for high power laser-related tasks such as light-generation, light-amplification, nonlinear-harmonic conversion etc. For optimization of these devices, accurate knowledge of the material thermal parameters is essential. Many optical and non-optical methods are currently in use, for the reliable estimation of the thermal parameters. The thermal diffusivity is a key parameter for dealing with ‘transient heat transport’ related problems. Although its importance in practical design for thermal management is well understood, its physical meaning however continues to be esoteric. The present effort concerns with a few investigations on the “Optical interrogation of ‘transient thermal conduction’ in dielectric solids”. In dielectric solids, the current understanding is that the conductive heat transport occurs only through phonons relevant to microscopic lattice vibrations. Introducing for the first time, a virtual linear translator motion as the basis for heat conduction in dielectric materials, the present investigation discusses an alternative physical mechanism and a new analytical model for the transient heat conduction in dielectric solids. The model brings into limelight a ‘new law of motion’ and a ‘new quantity’ which can be defined at every point in the material, through which time-varying heat flows resulting in time-varying temperature. Physically, this quantity is a measure for the linear translatory motion resulting from transient heat conduction. For step-temperature excitation it bears a simple algebraic relation to the thermal diffusivity of the material. This relationship helps to define the thermal diffusivity of a dielectric solid as the “translatory motion speed” measured at unit distance from the heat source. A novel two-beam interferometric technique is proposed and corroborated the proposed concept with significant advantages. Two new approaches are introduced to estimate thermal diffusivity of optically transparent dielectric solid; first of them involves measurement of the position dependent velocity of isothermal surface and second one depend on the measurement of position dependent instantaneous velocity of normalized moving intensity points. A ‘new mechanism’ is proposed and demonstrated to visualize, monitor and interrogate optically, the ‘linear translatory motion’ resulting from the transient heat flow due to step- temperature excitation. Two new approaches are introduced, first one is ‘mark’ and ‘track’ approach, it involves a new interaction between sample supporting unsteady heat flow with its ambient and produces optical mark. Thermal diffusivity is estimated by tracking the optical mark. Second one involves measurement of instantaneous velocity of optical mark for different step-temperature at a fixed location to estimate thermal diffusivity. A new inverse method is proposed to estimate thermal diffusivity and thermal conductivity from the volumetric specific heat capacity alone through thought experiment. A new method is proposed to predict volumetric specific heat capacity more accurately from thermal diffusivity.

The main goal of this thesis was to simulate a solar cell with the symbolic manipulation tool Maple and discuss the strength and weaknesses of using Maple instead of the already known simulation program PC1D. This was done mainly by solving the three essential differential equations governing the current density and excess electron and hole densities in the solar cell. This could be done easily by using known simplifications especially the low injection assumption. However it was also a success without using this particular simplification but the solutions had to be achieved using a numerical method instead of direct methods. The results were confirmed by setting up the same solar cell with PC1D. The conclusion is that Maple gives the user increased freedom when setting up the solar cell, however PC1D is easier to use if this freedom is not needed. At the end of this thesis a brief introduction is also made on the possibility of using Maple with a tandem cell setup instead of single junction.

This work studies the influence of field effect on large area 2 dimensional ribbons of fluids. A fluid of choice is confined in the channel of a metal-insulator-channel-insulator-metal architecture and is subjected to constant (d.c) or alternating (a.c) fields (de-pending on the application) along with a pressure drive flow. A general fluid would be composed of molecules having certain polarizability and be a dispersion of non-ionic and ionic particulates. The field effect response under pressure driven flow for this fluid would result in electrophoresis, electro osmosis, dielectrophoresis, dipole-dipole interaction and inverse electro osmosis phenomena. Using some of these phenomena we study applications related to desalination and energy harvesting with saline water as the ex-ample fluid for the former case, and solution processed poly vinyldene fluoride (PVDF) for the latter case. The geometrical features of \large area" and the \ribbon shape" can be taken advantage of to influence the design and performance for both applications. With regards to desalination, it is shown via experiments and theoretical models that the presence of alternating electric fields aid in ion separation along the flow when the saline water is subjected to laminar flow. Moreover, the power consumption is low due to the presence of the insulator. An average of 30% ion removal efficiency and 15% throughput is observed in the systems fabricated. Both performance parameters are discussion can be improved upon with larger channel lengths. The \2-D ribbon" and alternating field effect aid in achieving this by patterning the randomly distributed ions in the bulk into a smooth sheet charge and then repelling this sheet charge back into the bulk. The electric field exhibited by this sheet charge helps trap more ion sheets near the interface, thereby converting a surface ion trapping phenomena (when d.c is used) to a bulk phenomena and thereby improving efficiency. With regards to energy harvesting, a solution of PVDF in methyl ethyl ketone and 1-methyl-2-pyrollidone is confined to the \2-D ribbon" geometry and subject to high d.c fields. This aids in combining the fabrication, patterning and poling process for PVDF into one setup. Since the shape of the ribbon is defined by the shape of the channel, the ribbons (straight or serrated) can be used to sense forces of various magnitudes. More importantly experiments and theoretical models are studied for energy harvesting. Since the ribbon geometry defines the resonant frequency, large PVDF ribbon can be used to harvest energy from low frequency vibrations. Experiments show that up to 60 microwatt power can be harvested at 200 Hz and is sufficient to supplement the power for ICs.

This thesis describes the development and applications of an extension of DWS which enables the recovery of ‘localized’ mechanical properties, in a specified region of a complex jelly-like object which is inhomogeneous, marked out by the focal volume of an ultrasound transducer, also called the region-of-interest (ROI). Introduction of the sinusoidal forcing creates a sinusoidal phase variation in the detected light in a DWS experiment which modulates the measured intensity autocorrelation, g2 (τ ). Decay in the modulation depth with τ is used to recover the visco-elastic spectrum of the material in the ROI. En route to this, growth of the mean-squared dis- placement (MSD) with time is extracted from the modulation depth decay, which was verified first by the usual DWS experimental data from an homogeneous object with properties matching those in the ROI of the inhomogeneous object and then those obtained by solving the generalized Langevin equation (GLE) modelling the dynamics of a typical scattering centre in the ROI. A region-specific visco-elastic spectral map was obtained by scanning the inhomogeneous object by the ultrasound focal volume. Further, the resonant modes of the vibrating ROI were measured by locating the peaks of the modulation depth variation in g2(τ ) with respect to the ultrasound frequency. These resonant modes were made use of to recover elasticity of the material of the object in the ROI. Using a similar strategy, it was also shown that flow in pipe can be detected and flow rate computed by ‘tagging’ the photons passing through the pipe with a focussed ultrasound beam. It is demonstrated, both through experiments and simulations that the ultrasound-assisted technique devel- oped is better suited to both detect and quantitatively assess flow in a background of Brownian dynamics than the usual DWS. In particular, the MSD of particles in the flow, which shows forth a super-diffusive dynamics with MSD growing following τ α with α < 2, is captured over larger intervals of τ than was possible using existing methods. On the theoretical front, the main contribution is the derivation of the GLE, with multiplicative noise modulating the interaction ‘spring constant’. The noise is derived as an average effect of the micropolar rotations suffered by the ‘bath’ particles on the ‘system’ particle modelled. It has been shown that the ‘local’ dynamics of the system particle is nontrivially influenced by the dynamics, both translation and rotation, of ‘nonlocal’ bath particles.

<div>The present thesis was completed to satisfy two functions in our laboratory: (1) explore carbon-black (CB) as an additive for electrodeposited intrinsically conductive polymers (ICPs) to improve electrical properties across the electrode-electrolyte interface for use in neuromodulation; and (2) design a histology protocol that will analyze peripheral nerve system (PNS) tissue following implantation of conventional metal and modified conventional metal electrodes with the ICP poly(3,4-ethylenedioxythiophere):poly(styrenesulfonate)/carbon-black (PEDOT:PSS/CB). It would appear that the functions explored may seem unrelated, however, these two topics play a crucial role in designing a viable electrode for use in acute and chronic neuromodulation and the subsequent analysis required to determine the mechanical properties and overall biocompatibility of design.</div><div><br></div><div><div>A series of experiments with different PEDOT:PSS solutions containing varying amounts of suspended CB (n=19; 0 mg/mL to 2 mg/mL) were explored. Solutions were characterized using cyclic voltammetry (CV) using the intended electrode for deposition, composed of stainless steel (SS), as the working electrode (WE) to determine respective redox potentials. SS was chosen because of its inherently bad electrochemical properties, meaning that improved functionality post electrodeposition would be easy to identify. Immediately following CV, stainless-steel electrodes were electrodeposited using one of two techniques: (1) potentiostat, allowing the cell to rest at the redox potential required for bipolaron formation (0.9 V); or (2) galvanostat, where the electrode was submitted to a constant current of 200 mA and allowed to coat. Rapid electrochemical impedance spectroscopy was performed prior to and immediately following coating to determine the pre-electrochemical and post-electrochemical impedance characteristics. Results indicate that there was a positive relationship between the amount of CB additive and the relative impedance drop between the uncoated and coated counterparts. Furthermore, the modified electrochemical interfaces are substantially improved for use in frequency ranges of 10 Hz to 50 kHz, which encompass the ranges of our labs recently discovered low frequency alternating current (LFAC) for use in neuromodulation; thus indicating that PEDOT:PSS/CB modification may be used to improve impedance characteristics during our future LFAC experiments. This protocol, the one that contains the ideal concentration of carbon-black, was then recorded and will be used in our lab.</div></div><div><br></div><div><div>Histology protocols were developed to improve our labs capabilities of post-mortem analysis of PNS tissue. Processing and embedding preparations that explored included paraffin, acrylic, and frozen. Subsequently, staining protocols were developed; however, they varied as a function of the embedding media used; staining protocols developed incorporated progressive and regressive hematoxylin and eosin (H&E) staining as well as toluidine blue (TB). Tissue was sectioned and observed using light microscopy.</div></div>

<div>In a world of ever-increasing demand for energy while preventing adverse effects of climate</div><div>change, renewable energy has been sought after as a sustainable solution. To this end,</div><div>the last couple of decades have seen an advancement in research and development of solar</div><div>photovoltaic (PV) technology by leaps and bounds. This has led to a steady improvement</div><div>in the cost-effectiveness of solar PV as compared to the traditional sources of energy, e.g.,</div><div>fossil fuels as well as contemporary renewable energy sources such as wind and hydropower.</div><div>To further decrease the levelized cost of energy (LCOE) of solar PV, new materials and</div><div>technologies are being investigated and subsequently deployed as residential, commercial, and</div><div>utility-scale systems. One such innovation is called bifacial PV, which allows collection of</div><div>light from the front as well as rear surfaces of a flat PV panel.</div><div><br></div><div>In this thesis, we present a detailed investigation of bifacial solar PV farms analyzed across</div><div>the globe. We define the problem, explore the challenges, and collaborate with researchers</div><div>from academia and the PV industry to find a novel solution.</div><div><br></div><div>First, we begin by developing a multi-module computational framework to numerically</div><div>model a utility-scale bifacial solar PV farm. This requires integrating optical, electrical,</div><div>thermal, and economic models in order to estimate the energy yield and LCOE of a bifacial</div><div>PV system. The first hurdle is to re-formulate the LCOE so that the economist and the</div><div>technologist can collaborate seamlessly. Thus, we re-parameterize the LCOE expression</div><div>and validate our economic model with economists at the National Renewable Energy Lab</div><div>(NREL).</div><div><br></div><div>Second, we extend the existing optical and electrical models created for stand-alone</div><div>bifacial PV panels to models that can simulate a large-scale bifacial solar PV farm. This</div><div>brings the challenge of mathematically modeling solar farms and light collection on the rows</div><div>of PV panels elevated from the ground by taking into account the mutual shading between</div><div>the rows, reflections from the ground, and elevation-dependent light absorption on the rear</div><div>surface of the PV panels from several neighboring rows. Next, we integrate temperaturedependent</div><div>efficiency models to take into account the effects of location-dependent ambient</div><div>temperature, wind speed, and technology-varying temperature coefficients of the solar PV</div><div>system in consideration.</div><div><br></div><div>Third, we complete the comprehensive modeling of bifacial solar PV farms by including</div><div>two types of single-axis tracking algorithms viz. sun-tracking and power tracking. Using these</div><div>algorithms, we explore the best tracking orientation of solar farms i.e., East-West tracking</div><div>vs. North-South tracking for locations around the world. We further find the best land type</div><div>suitable for installation of these E/W or N/S tracking bifacial solar PV farms.</div><div><br></div><div>Fourth, we reduce the computation time of numerical modeling by utilizing the advantages</div><div>of machine learning algorithms. We train neural networks using data from the alreadybuilt</div><div>models to emulate the numerical modeling of a solar farm. Amazingly, we find the</div><div>computation time reduces by orders of magnitude while accurately estimating the energy</div><div>yield and LCOE of PV farms.</div><div><br></div><div>Fifth, we derive, compare, and experimentally validate the thermodynamic efficiency</div><div>limits of photovoltaic-to-electrochemical energy conversion for the purpose of storing solar</div><div>energy for future needs.</div><div><br></div><div>Finally, we present some new ideas and guidelines for future extensions of this thesis as</div><div>well as new challenges and problems that need further exploration.</div>

Density functional theory (DFT) calculations of polyethylene (PE) HVDC cable insulation have been performed for systems containing four different chemical impurities: acetophenone, cumene, $\alpha$-methyl styrene and $\alpha$-cumyl alcohol. Systems were generated by molecular dynamics (MD) equilibration at four different temperatures relevant for cable insulation applications: 277 K, 293 K, 343 K and 363 K. With the goal of gaining better measure of variations in hole and electron traps energies, four initial configurations were also stochastically generated at each temperature, which yielded four different final configurations after equilibration. The counterpoise correction scheme was implemented for DFT calculations, by distributing ghost atoms thought any empty pockets of space in between the PE chains. The PBE functional was selected for DFT simulations. The resulting band gaps were in agreement with those of earlier GGA-based studies, and thus lower by 3 eV than empirical band gaps. For all impurities, the first HOMO state and the first two LUMO states were generally located on the impurity molecule, forming one hole trap and two electron traps, but certain configurations generated increased electron trap numbers, or eliminated hole traps. No dependence could be derived between temperature and trap depth for either electron or hole traps. Mean electron trap energies were largely in agreement with results from earlier studies, they were deepest for acetophenone, and they varied by as much as 0.6 eV between different configurations. Hole traps are universally shallow and vary by up to 0.7 eV between configurations, and are similar in depth for all impurities. Results suggest that electron trap depths correlate with the presence of molecular features such as oxygen atoms and conjugated double bonds. The dependence of trap depth on the spatial configuration of the impurity molecule suggests that results could be improved by more precise quantum mechanical treatment of the dynamics of the impurity. / Täthetsfunktionalteori (DFT) har använts för beräkningar av isolering till HVDC kablar som består av polyeten innehållande fyra olika kemiska orenheter: acetofenon, kumen, alfa-metylstyren och alfa-kumylalkohol. System att studera genererades genom molekylärdynamisk ekvilibrering vid fyra olika temperaturer relevanta för tillämning till kabelisolering: 277 K, 293 K, 343 K och 363 K. För att få ett mått på de variationer som existerar i energierna på hål- och elektronfällor genererades stokastiskt fyra initialkonfigurationer vid varje temperatur, vilket fyra olika konfigurationer efter relaxering. Motviktskorrigering implementerades för DFT-beräkningar, genom att fördela "spökatomer" i de tomrum som bildas mellan PE-kedjorna i den amorfa fasen. PBE-funktionalen användes för DFT-simuleringar. De resulterande bandgapen stämde överens med tidigare GGA-baserade studier, och var därmed runt 3 eV smalare än empiriskt uppmätta bandgap. För alla orenheter var det första HOMO-tillståndet och de två första LUMO-tillstånden i allmänhet placerade på orenheten, vilket resulterade i en hålfälla och två elektronfällor, men vissa konfigurationer gav upphov till fler elektronfällor, eller eliminerade hålfällorna. Inget samband kunde härledas mellan temperaturen och djupet på fällorna för vare sig elektron- eller hålfällor. Medelvärdet på elektronfällornas energier överensstämde till stor del med resultat från tidigare studier, energierna var högst för acetofenon, och de varierade med så mycket som 0,6 eV mellan olika konfigurationer. Hålfällorna var genomgående grunda, varierade med upp till 0,7 eV mellan olika konfigurationer, och hade likartat djup för alla orenheter. Resultaten indikerar att variationerna elektronfällornas medeldjup uppstår på grund av orenheternas olika molekylära uppbyggnad: förekomst av syreatomer och konjugerade dubbelbindningar i orenheterna leder till djupare elektronfällor. Det faktum att djupet på elektron- och hålfällor varierar mellan olika rumsliga konfigurationer av av orenheten och polyetenstrukturen ger en antydan om att resultaten kan komma att förbättras om dynamiken hos orenheten simuleras med mer exakta kvantmekanisk metoder.

Dye-sensitized solar cells (DSC) have attracted considerable scientific and industrial interest during the past decade as an economically feasible alternative to conventional photovoltaic devices. DSCs have the potential to be as efficient as silicon solar cells, but at a fraction of the cost of silicon solar cells. The unique advantage of DSC compared to conventional solar cells is that the light absorption, electron transport and hole transport are handled by different components which reduces the chance of recombination. In the present work, to facilitate DSC with good energy conversion efficiency, its performance have been evaluated as a function of titania layer morphology, redox couple concentration and the catalytic layer on the counter electrode. The results that are obtained in the present investigations have been organized as follows Chapter 1 gives a brief exposure to DSC technology. Special emphasize has been on the structure and individual components of the DSC. Chapter 2 describes various experimental techniques that are employed to fabricate and characterize DSCs under study. Chapter 3 presents a systematic study of the characteristics of DSC made of three different types of electrodes namely: TiO2 nanotubes (TNT) which have excellent electron transport properties, TiO2 microspheres (TMS) which possess high surface area and light scattering ability and TiO2 nano particles (TNP) possessing high surface area. The electronic, morphological, optical and surface properties of individual electrodes are studied. The highest efficiency of 8.03% is obtained for DSCs prepared with TMS electrodes. A higher value of effective diffusion coefficient (Deff) and diffusion length (Ln) of electrons as obtained by electrochemical impedance spectroscopy (EIS) analysis confirms a high charge collection efficiency in microsphere based cell. Chapter 4 gives a detailed study of DSCs fabricated with a tri-layer photo anode with TNTs as light scattering layer. The tri-layer structure has given an enhanced efficiency of 7.15% which is 16% higher than TNP based cell and 40% higher than TNT based cells. Chapter 5 deals with the investigations on the effect of concentration of redox couple on the photovoltaic properties of DSC for different ratios of [I2] to [LiI] (1:2, 1:5 and 1:10) with five viii concentrations of I2 namely 0.01 M, 0.03 M, 0.05 M, 0.08 M and 0.1M in acetonitrile. It is found that the open circuit potential (Voc) decreases with increase in the ratio of redox couple whereas short circuit current density (Jsc) and fill factor (FF) increase. The reason for the decline in Voc is the higher recombination between electrons in the conduction band of TiO2 and the I3- ions present in the electrolyte, induced by the absorptive Li+ ions. In addition using EIS it is found that the τ improves with the increase in [LiI] at a particular [I2], whereas at a fixed [I2]/ [LiI] ratio the increase in [I2] is found to reduce the τ and Deff due to the enhanced recombination. Chapter 6 describes the application of carbon based counter electrode (CE) materials for DSCs. Two counter electrode materials have been investigated namely (1) Multiwalled carbon nanotubes (MWCNT) synthesized by pyrolysis method and (2) Platinum decorated multiwalled carbon nanotubes (Pt/MWCNT) prepared by chemical reduction of platinum precursors. Using Pt/MWCNT composite electrode the DSC achieved an energy conversion efficiency of 6.5 %. From the analysis on symmetric cells, it is found that electro catalytic activity of Pt/MWCNT CE is similar to that of platinum CE, though the platinum loading is very less for the former. This is attributed to the effective utilization of catalyst owing to high surface area arising from the increased surface roughness. Chapter 7 discusses the application of titanium foil in place of glass substrate for the photo anode. The titanium foil offers fabrication of flexible DSC. The performance of DSC with TMS layers and aligned titania nanotube arrays (TNA) prepared by anodization method is studied. Compared to TMS based cell, TNA has given a better efficiency at a lower thickness. Chapter 8 presents the scheme used to seal DSCs and its stability analysis. We have employed the usual hot melt sealing for edge whereas hole sealing is carried out with tooth pick and a UV curable adhesive. The degradation in efficiency is found to be 20% for low efficiency cells whereas, for high efficiency cells it is found to be 45% after 45 days. The leakage of highly volatile acetonitrile through the edge and hole is found to be responsible for the reduction in the performance of the device. Hence a high temperature sealing method is proposed to fabricate stable cells. Chapter 9 gives summary and conclusions of the present work

This thesis is concerned with the development and application of laser induced thermal grating spectroscopy (LITGS) as a tool for thermometry in reacting and non-reacting flows. LITGS signals, which require resonant excitation of an absorbing species in the measurement region to produce a thermal grating, are acquired for systematic measurements of temperature in high pressure flames using OH and NO as target absorbing species in the burned gas. The signal obtained in LITGS measurements appears in the form of a time-based signal with a characteristic frequency proportional to the value or the sound speed of the local medium. With knowledge of the gas composition, the temperature can be derived from the speed of sound measurement. LITGS thermometry using resonant excitation of OH in the burned gas region of in oxygen enriched CH4/O2/N2 and CH4/air laminar flames was performed at elevated pressure (0.5 MPa) for a range of conditions. Measurements were acquired in oxygen enriched flames to provide an environment in which to demonstrate LITGS thermometry under high temperature conditions (up to 2900 K). The primary parameters that influence the quality of LITGS signal were also investigated. The signal contrast, which acts as a marker for the strength of the frequency oscillations, is shown to increase with an increase in the burnt gas density at the measurement point. LITGS employing resonant excitation of NO is also demonstrated for quantitative measurements of temperature in three environments – a static pressure cell at ambient temperature, a non-reacting heated jet at ambient pressure and a laminar premixed CH4/NH3/air flame operating at 0.5 MPa. Flame temperature measurements were acquired at various locations in the burned gas close to a water-cooled stagnation plate, demonstrating the capability of NO-LITGS thermometry for measuring the spatial distribution of temperature in combustion environments. In addition, the parameters that in influence the local temperature rise due to LITGS were also investigated in continuous vapour flows of acetone/air and toluene/air mixtures at atmospheric conditions. Acetone and toluene are commonly targeted species in previous LITGS measurements due to their favourable absorption characteristics. Results indicate that LITGS has the potential to produce accurate and precise measurements of temperature in non-reacting flows, but that the product of the pump intensity at the probe volume and the absorber concentration must remain relatively low to avoid significant localised heating of the measurement region.