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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Invitro measurement of glucose concentration in water solution by optical methods.

January 2004 (has links)
Chu Lut-Hey. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 137-140). / Abstracts in English and Chinese. / Abstract --- p.II / Acknowledgement --- p.V / List of Tables --- p.IX / List of Figures --- p.X / List of Abbreviations --- p.XIII / Chapter 1 --- Introduction / Chapter 1.1 --- Objectives.l --- p.1 / Chapter 1.2 --- What is diabetes mellitus?. --- p.1 / Chapter 1.3 --- "Review of ""Technique for blood glucose measurement""" --- p.3 / Chapter 1.3.1 --- Conventional blood glucose meter --- p.4 / Chapter 1.3.2 --- Semi-invasive blood glucose meter --- p.5 / Chapter 1.3.3 --- Surfacelasmon resonance (SPR) method --- p.6 / Chapter 1.3.4 --- Non-invasive blood glucose meters --- p.7 / Chapter 1.4 --- Research directions --- p.8 / Chapter 1.5 --- Data analysis methods --- p.9 / Chapter 1.6 --- Organization of the thesis --- p.10 / Chapter 2 --- Spectral Data Analysis Methods / Chapter 2.1 --- What is spectral data? --- p.12 / Chapter 2.2 --- Nature of spectral data --- p.12 / Chapter 2.3 --- How to interpret the spectral data? --- p.15 / Chapter 2.3.1 --- Linear regression --- p.15 / Chapter 2.3.2 --- Multiple linear regression (MLR) --- p.17 / Chapter 2.3.2.1 --- Data reduction --- p.19 / Chapter 2.3.3 --- Bilinear modeling (BLM) --- p.21 / Chapter 2.3.3.1 --- artial least square regression (PLSR) --- p.23 / Chapter 2.3.3.2 --- Model reliability --- p.24 / Chapter 2.3.3.3 --- LS segmentation analysis --- p.25 / Chapter 2.4 --- Session discussion and conclusion --- p.27 / Chapter 3 --- Surfacelasmon Resonance (SPR) Experiments and Analysis / Chapter 3.1 --- Intrcduction --- p.29 / Chapter 3.2 --- Theory --- p.30 / Chapter 3.2.1 --- Maxwell's equations --- p.30 / Chapter 3.2.2 --- olarization of EM wave --- p.32 / Chapter 3.2.3 --- Boundary condition --- p.33 / Chapter 3.2.4 --- Total internal reflection --- p.37 / Chapter 3.2.5 --- hase shift of total internal reflection wave --- p.38 / Chapter 3.2.6 --- Kretschmannrism configuration --- p.38 / Chapter 3.2.7 --- Conditions affecting SPR --- p.41 / Chapter 3.3 --- Different SPR configuration systems --- p.44 / Chapter 3.3.1 --- rinciple of angular-based interrogation SPR setup --- p.44 / Chapter 3.3.2 --- rinciple of intensity-based interrogation SPR setup --- p.45 / Chapter 3.3.3 --- rinciple of wavelength-based interrogation SPR setup --- p.45 / Chapter 3.3.4 --- hase-based interrogation SPR setup --- p.47 / Chapter 3.3.4.1 --- Michelson Interferometer --- p.48 / Chapter 3.3.4.2 --- Thehase-based setup --- p.49 / Chapter 3.3.5 --- Comparison and discussion of different configurations --- p.51 / Chapter 3.4 --- SPR experiment adopts wavelengths-based interrogation setup --- p.54 / Chapter 3.4.1 --- The experiment setup --- p.54 / Chapter 3.4.1.1 --- Samplereparation --- p.58 / Chapter 3.4.1.2 --- Experiment Result using 928 nm and 1120 nm initial resonant wavelength --- p.58 / Chapter 3.4.2 --- Experimental data analysis --- p.60 / Chapter 3.4.2.1 --- Conventional SPR data analysis --- p.61 / Chapter 3.4.2.1.1 --- Data analysis using minimum hunting witholynomial fit --- p.62 / Chapter 3.4.3 --- LS regression analysis for SPR data --- p.67 / Chapter 3.5 --- Session discussion and conclusion --- p.71 / Chapter 4 --- Near-Infrared Spectroscopy Experiment and Analysis / Chapter 4.1 --- Overview of near-infrared spectroscopy --- p.74 / Chapter 4.1.1 --- Electromagnetic spectrum --- p.75 / Chapter 4.1.2 --- Molecules vibration --- p.76 / Chapter 4.1.3 --- Law of absorption: Lambert-Beer Law --- p.77 / Chapter 4.2 --- Near Infrared Spectrometer --- p.79 / Chapter 4.2.1 --- Dispersive NIR spectrometer --- p.79 / Chapter 4.2.2 --- Fourier-Transformed NIR spectrometer --- p.83 / Chapter 4.2.3 --- Comparison between dispersive NIR and FT-NIR spectrometers --- p.85 / Chapter 4.2.4 --- Self-established monochromator based spectrometer --- p.87 / Chapter 4.2.4.1 --- Choose of detector andhotonic signal conversion unit --- p.90 / Chapter 4.3 --- Experimental result of NIR-spectrum by self-established spectrometer --- p.95 / Chapter 4.3.1 --- New approach for improving RMSEP without normalization of water spectrum as background information --- p.105 / Chapter 4.4 --- Experimental results of NIR-spectrum by commercial spectrometers --- p.109 / Chapter 4.5 --- Instrumentation limitation of NIR spectrometer --- p.117 / Chapter 4.6 --- Session Discussion and conclusion --- p.119 / Chapter 5 --- Conclusions and Suggestions for the Future Work / Chapter 5.1 --- Research aim and contributions --- p.126 / Chapter 5.2 --- Discussion on experiments --- p.128 / Chapter 5.3 --- Future work --- p.131 / Chapter 5.4 --- Conclusion --- p.134 / Reference: --- p.136 / Appendixes: --- p.141 / Appendix A Different approaches for non-invasive glucose measurement --- p.142 / Appendix B Calibration model of the SPR experimental result with 1120 nm as initial resonance wavelength --- p.145 / Appendix C Matlabrogram written for data analysis and simulation --- p.146 / Appendix D Detail specification of the monochromator using in our laboratory --- p.150 / Appendix E Monochromator Controlrogram --- p.156 / Appendix F The throughput example copied from the handbook of ORIEL Instruments --- p.165 / Appendix G RMSEPlot of the data obtained by self-established spectrometer with and without datare-treatments --- p.166 / "Appendix H RMSEPlot of the raw data obtained from the three different commercial machines (Vector-22N/C, NIRSystem 6500 and NIRSystem XDS) with and without datare-treatment" --- p.176
112

Near infrared laser spectroscopy of carbon-containing plasmas. / CUHK electronic theses & dissertations collection

January 2010 (has links)
In addition, two unknown vibronic bands have been observed in the 12150 cm-1 region and 12450 cm-1 region. From the observed linewidths, isotopic shift of the transition frequency and appearance of intricate spectral pattern, it is plausible that these bands may be due to C2 under the perturbation of a state inaccessible by dipole transition. Further analysis of these bands are underway. / The unprecedented sensitivity and resolution achieved by our spectrometer allows the measurement of the very weak Phillips band system (A 1piu - X1Sigmag +) of C2 in the plasma of methane and helium at a ratio of 1:170 generated under very mild ac hollow cathode discharge conditions. A total of eleven vibronic bands of the Phillips system have been observed in the region from 10300 cm-1 to 14250 cm-1 and analyzed based on the previous work. Combining the observed transition frequencies with those from Douay et al. [J. Mol. Spectrosc. 131, 250 (1988)], a set of spectroscopic constants for both the X1Sigma g+ and A1piu states have been obtained using least-squares fitting. Excellent agreement has been found between determined molecular constants and those found in the literature. The observation of the high upsilon levels in the 1piu state allows the determination of high order anharmonic constants oeze and oeae for the first time. / This thesis reports the construction of a custom-designed experimental setup for the high resolution near infrared spectroscopic studies of molecular ions and radicals generated in gaseous plasma. The home-built near infrared spectrometer system has a frequency resolution of 500 kHz and a frequency accuracy of ∼0.0010 cm-1 with a detection sensitivity of DeltaI/I of 10-6 using zero background concentration modulated phase sensitive detection scheme. An in-house program has been designed for data acquisition, frequency calibration and data processing and storage. / Yeung, Shun Hin. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 129-134). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
113

Neutralization and a Proposed Application to Israel

Tinkham, John Alfred 01 January 1971 (has links)
No description available.
114

Applications of near-infrared spectroscopy in temperature modeling of aqueous-based samples and polymer characterization

Kuda-Malwathumullage, Chamathca Priyanwada 01 December 2013 (has links)
Near-infrared (NIR) spectroscopy is a widely used technique in quantitative analytical applications. Near-infrared spectroscopy is commonly used in clinical, environmental and industrial applications because of its compatibility with aqueous samples and with relatively thick samples. However, NIR spectra typically contain weak and highly overlapped spectral features which require multivariate data analysis techniques (chemometrics) to yield meaningful and chemically relevant information. This dissertation consists of two main themes which include applications of NIR spectroscopy combined with chemometrics to (1) model temperatures in clinically relevant aqueous-based samples and (2) model temperature and moisture content in nylon-6,6 polymers. This research employed overtone and combination bands of C-H, O-H and N-H bonds situated in the 4000 - 5000 cm-1 region to develop partial least-squares (PLS) regression models to predict analyte properties such as temperature, concentration and moisture content. The research described in the first part of this dissertation includes the development of a spectral preprocessing strategy based on the standard variate transform (SNV) and discrete wavelet transform (DWT) to isolate the low-frequency baseline information which carries the spectral features due to temperature fluctuations in aqueous-based samples. This approach was used to develop calibration models to determine the temperature of aqueous-based samples directly from their NIR spectra. This is an important development due to the fact that extreme temperature sensitivity of the underlying water bands can lead to poor quantitative analyte prediction results. These temperature models were developed using pH 7.4 phosphate buffer solutions spanning the range of 20 to 40.5 °C. Following the temperature models, a temperature-correction strategy based on the systematic pattern of concentration residuals was successfully developed to improve quantitative analyte predictions in aqueous-based samples. These analyte prediction models included glucose solutions and glucose-lactate mixture solutions prepared in pH 7.4 phosphate buffer. The computed temperature models gave excellent long-term prediction results. The temperature correction strategy gave promising results with the glucose solutions as well as the glucose-lactate mixture solutions. The research presented in the second part of this dissertation includes the development of calibration models to determine the temperature and moisture content of a piece of nylon-6,6 polymer directly from its NIR spectrum combining SNV and DWT procedures followed by PLS regression. Both models gave good long-term prediction results and predicted well across different nylon-6,6 sheets. Computed moisture model provides a reliable and fast method to determine the moisture content of a nylon polymer when compared to existing techniques. Extended research towards polymer characterization including preliminary investigations of inhomogeneous nature of nylon polymers using infrared microscopy is documented in the latter part of this dissertation.
115

The political integration of the Kurds in Turkey

Ertur, Kathleen Palmer 01 January 1979 (has links)
The purpose of this thesis is to illustrate the situation of the Kurdish minority in Turkey within the theoretical parameters of political integration. The problem: are the Kurds in Turkey politically integrated? Within the definition of political development generally, and of political integration specifically, are found problem areas inherent to a modernizing polity. These problem areas of identity, legitimacy, penetration, participation~ and distribution are the basis of analysis in determining the extent of political integration for the Kurds in Turkey. When these five problem areas are adequately dealt with in order to achieve the goals of equality, capacity and differentiation, political integration is achieved.
116

Phillips Cutright's "National Political Development" and the Case of Saudi Arabia

Freeman, Mark Thomas 01 January 1994 (has links)
No description available.
117

Morphology dependent resonance of a microscope and its application in near-field scanning optical microscopy

Morrish, Dru, DruMorrish@gmail.com January 2005 (has links)
In recent times, near-field optical microscopy has received increasing attention for its ability to obtain high-resolution images beyond the diffraction limit. Near-field optical microscopy is achieved via the positioning and manipulation of a probe on a scale less than the wavelength of the incident light. Despite many variations in the mechanical design of near-field optical microscopes almost all rely on direct mechanical access of a cantilever or a derivative form to probe the sample. This constricts the study to surface examinations in simple sample environments. Distance regulation between the sample surface and the delicate probe requires its own feedback mechanism. Determination of feedback is achieved through monitoring the shift of resonance of one arm of a 'tuning fork', which is caused by the interaction of the probes tip with the Van der Waals force. Van der Waals force emanates from atom-atom interaction at the top of the sample surface. Environmental contamination of the sample surface with additional molecules such as water makes accurate measurement of these forces particularly challenging. The near-field study of living biological material is extremely difficult as an aqueous environment is required for its extended survival. Probe-sample interactions within an aqueous environment that result in strong detectable signal is a challenging problem that receives considerable attention and is a focus of this thesis. In order to increase the detectible signal a localised field enhancement in the probing region is required. The excitation of an optically resonant probe by morphology dependent resonance (MDR) provides a strong localised field enhancement. Efficient MDR excitation requires important coupling conditions be met, of which the localisation of the incident excitation is a critical factor. Evanescent coupling by frustrated total internal reflection to a MDR microcavity provides an ideal method for localised excitation. However it has severe drawbacks if the probe is to be manipulated in a scanning process. Tightly focusing the incident illumination by a high numerical aperture objective lens provides the degree of freedom to enable both MDR excitation and remote manipulation. Two-photon nonlinear excitation is shown to couple efficiently to MDR modes due to the high spatial localisation of the incident excitation in three-dimensions. The dependence of incident excitation localisation by high numerical aperture objective on MDR efficiency is thoroughly examined in this thesis. The excitation of MDR can be enhanced by up to 10 times with the localisation of the incident illumination from the centre of the microcavity to its perimeter. Illuminating through a high numerical aperture objective enables the remote noninvasive manipulation of a microcavity probe by laser trapping. The transfer of photon momentum from the reflection and refraction of the trapping beam is sufficient enough to exert piconewtons of force on a trapped particle. This allows the particle to be held and scanned in a predictable fashion in all three-dimensions. Optical trapping removes the need for invasive mechanical access to the sample surface and provides a means of remote distance regulation between the trapped probe and the sample. The femtosecond pulsed beam utilised in this thesis allows the simultaneous induction of two-photon excitation and laser trapping. It is found in this thesis that a MDR microcavity can be excited and translated in an efficient manner. The application of this technique to laser trapped near-field microscopy and single molecule detection is of particular interest. Monitoring the response of the MDR signal as it is scanned over a sample object enables a near-field image to be built up. As the enhanced evanescent field from the propagation of MDR modes around a microcavity interacts with different parts of the sample, a measurable difference in energy leakage from the cavity modes occurs. The definitive spectral properties of MDR enables a multidimensional approach to imaging and sensing, a focus of this thesis. Examining the spectral modality of the MDR signal can lead to a contrast enhancement in laser trapped imaging. Observing a single MDR mode during the scanning process can increase the image contrast by up to 1:23 times compared to that of the integrated MDR fluorescence spectrum. The work presented in this thesis leads to the possibility of two-photon fluorescence excitation of MDR in combination with laser trapping becoming a valuable tool in near- field imaging, sensing and single molecule detection in vivo. It has been demonstrated that particle scanned, two-photon fluorescence excitation of MDR, by laser trapping 'tweezers' can provide a contrast enhancement and multiple imaging modalities. The spectral imaging modality has particular benefits for image contrast enhancements.
118

Automated Error Assessment in Spherical Near-Field Antenna Measurements

Pelland, Patrick 27 May 2011 (has links)
This thesis will focus on spherical near-field antenna measurements and the methods developed or modified for the work of this thesis to estimate the uncertainty in a particular far-field radiation pattern. We will discuss the need for error assessment in spherical near-field antenna measurements. A procedure will be proposed that, in an automated fashion, can be used to determine the overall uncertainty in the measured far-field radiation pattern of a particular antenna. This overall uncertainty will be the result of a combination of several known sources of error common to SNF measurements. This procedure will consist of several standard SNF measurements, some newly developed tests, and several stages of post-processing of the measured data. The automated procedure will be tested on four antennas of various operating frequencies and directivities to verify its functionality. Finally, total uncertainty data will be presented to the reader in several formats.
119

Study of Cyanine Dye Binding to Amino Acids and Its Analytical Utility

Merid, Yonathan 29 April 2010 (has links)
Investigation of the NIR cyanine dye MHI-36 shows binding affinity to charged amino acids. This cyanine dye showed aggregation and dimer formation at higher dye concentration (2.0x10-3 M) induced by lysine. When dye concentration decreased to 1.0x10-4M no strong aggregate formation was viewed. Dye shows strong binding and selectivity properties towards charged amino acids lysine and arginine, compared to neutral leucine. It’s believed the positively charged presence was able to break and disrupt the conjugated π- π bonds at lower dye concentration. Computational work showed intramolecular aggregation of the phenyl groups on the dye. These aggregates are believed to create electron rich environment suitable for lysine interaction.
120

Multiscale Reservoir Simulation: Layer Design, Full Field Pseudoization and Near Well Modeling

Du, Song 14 March 2013 (has links)
In the past decades, considerable effort has been put into developing high resolution geological models for oil and gas reservoirs. Although the growth of computational power is rapid, the static model size still exceeds the model size for routine reservoir simulation. We develop and apply a variety of grid coarsening and refinement algorithms and single and multiphase upscaling approaches, applied to tight gas and conventional reservoir models. The proposed research is organized into three areas. First the upgridding of detailed three dimensional geologic models is studied. We propose an improved layer design algorithm with considerations of accuracy and efficiency. This involves developing measures of reservoir heterogeneity and using these measures to design an optimal grouping of geologic model layers for flow simulation. The optimal design is shown to be a tradeoff between the desire to preserve the reservoir heterogeneity and a desire to minimize the simulation time. The statistical analysis is validated by comparison with flow simulation results. Accurate upgridding/upscaling of single-phase parameters is necessary. However, it does not always satisfy the accuracy requirements, especially for the model which is aggressively coarsened. We introduce a pseudoization method with total mobility and effective fractional flow as the major targets. This pseudoization method helps to push upgridding/coarsening degree to the limit but still be able to reproduce the fine scale field performance. In practice, it is common to not use a different set of pseudos for every coarse cell; only a limited number of pseudo functions should be generated for different “rock types” or geological zones. For similar well patterns and well control conditions, applying pseudo is able to reproduce the fine scale performance for different simulation runs. This is the second proposed research area. Finally, it is necessary to increase flow resolution for precise field history matching and forecasting. This has received increasing attention, especially when studying hydraulically fractured wells in unconventional reservoirs. We propose a multiscale reservoir simulation model combining local grid refinement (LGR) and pillar-based upscaling for tight gas reservoir performance prediction. Pillar-based coarsening away from the wells is designed for tight gas reservoirs. It compensates for the extra computational cost from LGR, which is used to represent hydraulic fractures. Overall reservoir performances, including the accuracy and efficiency, are evaluated.

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