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It takes 3~5 years to finish a power plaint project including location, reliability, environment evaluating, investigation, etc. In addition, it is difficulty to get a right place and hinder by the environment protection. So, it is an important class on boosting the existing power generation capacity. It was used to enhance power generation capacity by increasing the combustion chamber temperature in traditional way. However, it not only increases the exhaust temperature of gas turbine, but also increase the compressor ration. However, it is more difficulty on the design of gas turbine. And then we consider the other way in this thesis by reducing inlet air temperature of compressor to increase the density and flow of air and the power generation capacity. The result is magic that the power generation capacity enhance 10% ~20%. The analysis of Combustion Turbine Inlet Air Cooling System by Absorption refrigerant system(CTIAC-ABS) describe in chapter 2 including fundamental of a gas turbine, the absorption refrigerant chiller, the inlet cooling coil and cogeneration system. It lets us know how to select the style of cogeneration and specification of an absorption refrigerant chiller. It is important to consider the mass condensate water in the air side of inlet cooling coil. The author suggest to use the analysis method of wet-coil developed by Threlkeld(1970). The CTIAC system could be used to the Gas Turbine System, Gas Turbine with HRSG System and Combined System. Because of there is not high pressure steam, we can use the fired-gas absorption refrigerant system as the source of chiller on the CTIAC-ABS system. There is the high pressure steam of Gas Turbine with HRSG System and Combined System. So we can divided the high pressure steam into two part, one to process and the other could be used as the heat source of absorption refrigerant chiller There are two advantages of using CTIAC-ABS on cogeneration power plaint. 1.The new purpose of mass high pressure steam could be used in cogeneration power plaint in Taiwan. 2.Reduction operational cost of CTIAC-ABS The author finished the sensibility of power generation capacity with the analysis of practical operative data, classification of gas turbine and the power plaint Simulation program (GateCycle). When the compressor inlet temperature decrease from 30OC to 10OC, the results are : air flow rate increase 6.3%, fuel flow rate increase 5.95%, exhaust air temperature decrease 1.7% and exhaust air flow rate increase 6.3%, net power output increase 12.2%, heat rat decrease 3.7% and thermal efficiency upward 1.32%.Then, the author got a simulative equation of power capacity. The typical gas turbines operate at full-load condition, 52.25% of annual hours, in 1998 in Taiwan. Gas turbines were almost full load on daytime and half-load or closed at night. If we apply the CTIAC-ABS system on TPC's combined power plant, it can operate at 8:00~18:00 on daytime and shutdown at night. If there is high pressure steam in the cogeneration with HRSG, the CTIAC-ABS system can operate at the time that the cogeneration power plant is operative. How to decide the capacity of absorption refrigerant chiller? The author decided the maximum capacity of absorption refrigerant chiller operating at 31OC , 80%RH of weather condition that limit by 2.5% ***. The author forecasts the lowest compressor inlet air temperature will be 10OC. The steam double-effect CTIAC-ABS system could make the compressor inlet air temperature decrease from 30OC to 10 OC and enhances the heat rate 3.8%, the thermal efficiency 1.2%. The fired-direct CTIAC-ABS system also enhances the heat rate 5% and the thermal efficiency 1.5%. The results are close to the simulation of GateCycle program. So, the author compared the result of simulation with real data that the optimumal operative point of the CTIAC-ABS system is 10OC.

In this thesis, we have setup the measurement systems for photocurrent and electro-absorption (Da) spectroscopy, and have investigated the optical characteristics of semiconductor quantum well structures in the long wavelength regime. The measured samples are of three epi-structures including a p-i-n laser structure of the symmetric multiple quantum wells (SMQWs), a p-i-n laser structure of the asymmetric multiple quantum wells (AMQWs), and n-i-n BRAQWETS structures. The samples are fabricated in mesa type photodiode structures for the measurements. From the Da spectrum of the n-i-n BRAQWETS structures, we observe a blue shift ~ 10nm of Da peak caused by band filling effect at +5V bias. Besides, a red shift ~ 2nm has been obtained at ¡V5V bias caused by the quantum-confined Stark effect. The photocurrent spectrum of the SMQWs shows an e1-hh1 absorption peak at hn=0.813eV (l=1.525mm) which matches the photoluminesce spectrum. The e1-hh1 transition has a red-shift ~ 38nm at ¡V5V bias for the SMQWs. For the AMQWs consisting of 5, 10, 15nm wells, we observe the e1-hh1 absorption peaks at 0.758eV (l=1.64mm), 0.772eV (l=1.6mm) and 0.797eV (l=1.55mm), respectively. As the AMQWs biased at ¡V5V, a red-shift ~ 25nm is obtained for the e1-hh1 transition corresponding to the 15nm-wide wells.

In this study, a set of full-scale two-stage-in-series scrubbing tower was constructed to test its performance for desulfurization of biogas from three anaerobic UASB (upflow anaerobic sludge blanket) reactors of a wastewater plant for treating corn-syrup processing wastewater. Each stage of the absorbing towers was constructed from a 0.6m ¡Ñ 6 m (I.D. ¡Ñ H) plastic column packed with plastic packings (4¡¨ K6 Heilex-Type or 2.5¡¨ Crown-Biopacks with packing heights of 5 m and 3.65 m, respectively). Effluent from the activated sludge sedimentation tank of the wastewater plant was used as a scrubbing liquid and the tower effluent liquid was discharged into the activated sludge tank for oxidation of the absorbed hydrogen sulfide. Results of a continuous operation period of 20 weeks indicate that H2S of 380-19,000 ppm in the biogas could be reduced to 1-2,100 ppm by the scrubbing towers with superficial liquid and gas velocities of GL = 13.2-28.1 and GV = 306-642 m/h, respectively. On an average, the effluent gas contained a H2S concentration of less than 300 ppm and the removal efficacy was more than 96%. Results also indicate that as pH of the scrubbing liquid increased from 7.7 to 8.8, the overall H2S removal efficacy raised from 86 to 98%. About 1/3 of the absorbed H2S-S was detected as H2S-S and SO4-2-S in the tower effluent. The rest was supposed to be as elemental sulfur in a slimy form which sticked to the packing surface. This might be the reason for the increasing pressure drop with the operation time. A set of performance and gas-liquid equilibrium equations were proposed to estimated the influence of liquid pH, gas and liquid flow rates, and packing height on the H2S removal efficacy. Calculation results indicate, at 30oC, the minimum liquid/gas ratios (L/G)min for the absorption are 0.043 and 0.014 m3/m3, respectively, for fresh absorbing liquids with pH = 8.0 and 8.5. Based on the proposed equations and the experimental data, the volumetric mass-transfer coefficient Kya for H2S absorption in the towers could be expressed approximately as Kya =1.15¡Ñ1017GV1.0GL-3.0 with GV =304-644 and GL = 15.1-28.1 m3/m2.h, and liquid pH 7.7-8.6. It was supposed that too much liquid loading leads to a decrease in the specific area a for mass transfer which results in the Kya decrease.

The work of this thesis includes designs, molecular beam epitaxy (MBE) growths and optical study of electro-absorption modulator (EAM) structures. Three EAM structures are designed near 1.5 um : symmetric, asymmetric multiple quantum wells (MQWs) of TE polarization, and polarization insensitive MQWs. For symmetric and asymmetric MQWs simulation of TE polarization, their red-shift are 31 nm and 50 nm, respectively, as the electric field decrease from -40 kV/cm to -120 kV/cm. For polarization insensitive MQWs, we use the strained quantum-well concept to achieve same transition energy and absorption. After growth by MBE system, the samples were fabricated in mesa type by photolithography and wet etching. For symmetric and asymmetric quantum wells of TE polarization¡Gthe red-shift are 16 nm and 49 nm, respectively, as the bias decrease form 0-1 volt to 0-6 volt. Because of small ¡µn near subband transition energy, these two samples exhibit small chirp parameter. However, the photoluminescence (PL) and photocurrent spectra of these two ones were not near 1.5 um and obvious absorption edge. The possible reason is that the molecular beam flux have changed during growth. For polarization insensitive MQWs, the PL spectra shows 1494 nm, which only 25.6 nm differ from our design. Also, the photocurrent spectra of TE and TM polarization nearly exhibit same transition energy and have small chirp parameter.

We report results for the development of a flow-through integrated cavity absorption meter (ICAM.) Absorption measurements have been made with 2% or less change in the signal in the presence of up to 10 m-1 of scattering in the medium. The operating range of the ICAM ranges from 0.004 m-1 to over 40 m-1 of absorption. This range allows one to use a single instrument to measure the absorption from sediment laden rivers out to the cleanest of ocean waters. Further, the ICAM signal has been shown to be independent of the flow rate and turbulence in the medium. In addition we report the development of a diffuse reflector which, to our best knowledge, has the highest measured diffuse reflectivity of 0.998 at 532 nm and 0.996 at 266 nm. We also show that the average distance a photon travels between successive reflections in an integrating cavity of arbitrary shape is four times the volume divided by the surface area, 4 V/S. Further, for a cavity which is formed by planes tangent to an inscribed sphere and which maintains a homogeneous and isotropic field, the average distance traveled by a photon between successive reflections is equal to 4 V/S of the inscribed sphere. Thus, each cavity has the same ratio of V/S as the inscribed sphere. These advances lead to an increase in the sensitivity of absorption spectroscopy. The sensitivity approaches that of cavity ring down spectroscopy (CARS), without the adverse scattering effects traditionally associated with CARS.

This dissertation describes the design, fabrication and testing of an oblique incidence diffuse reflectance spectrometry (OIDRS) system for in-vivo and noninvasive detection of epithelial cancer. Two probes were fabricated using micromachining technology, which plays a significant role in the probe development by enabling device miniaturization, low-cost fabrication and precise assembly. The fist probe was developed and clinically tested for skin cancer detection. This probe consists of three source fibers, two linear array of collection fibers and four micromachined positioning devices for accurate alignment of the fibers. The spatially resolved diffuse reflectance spectra from 167 pigmented and 78 non-pigmented skin abnormalities were measured and used to design a set of classifiers to separate them into benign or malignant ones. These classifiers perform with an overall classification rate of 91%. The absorption and reduced scattering coefficient spectra were estimated to link the anatomic and physiologic properties of the lesions with the optical diagnosis. The melanoma cases presented larger average absorption and reduced scattering spectra than the dysplastic and benign ones. A second probe was designed to demonstrate the feasibility of a miniaturized ?side viewing? optical sensor probe for OIDRS. The sensor probe consists of a lithographically patterned polymer waveguides chip and two micromachined positioning substrates. This miniaturize probe was used to measure twenty ex-vivo esophageal samples. Two statistical classifiers were designed to separate the esophageal cases. The first one distinguishes benign and low dysplastic from high dysplastic and cancerous lesions. The second classifier separates benign lesions from low dysplastic ones. Both classifiers generated a classification rate of 100%.

New improved model was developed to calculate the absorption and refractive-index spectra in the band-edge region for all the important compound semiconductors. An accurate absorption model including Coulomb interaction and Urbach-broadened band edge has been demonstrated for direct bandgap semiconductors. We have developed a accurate model in which a piecewise linear approximation is used for the shape of the absorption spectrum. We also propose a steep-edged compound Lorentzian line-shape function (SCL-LSF) for modeling the Urbach tail, and the line broadening of exciton absorptions. The results of applying this fitting procedure to the absorption spectra of GaAs, InP and InAs are presented, and a consistent set of band parameters are extracted. The analytical absorption model is suitable for a complete closed-form Kramers-Kronig transform of the absorption spectrum to obtain the refractive index spectrum. A band-to-band Coulomb interaction model for the refractive index spectra is presented of AlxGa1-xAs for 0 < x < 0.412, and In0.53Ga0.47As ternary semiconductors at photon energies near and above the band gap. An accurate absorption model is used to calculate the contribution on the refractive index near band-edge region through a complete closed-form Kramers-Kronig transform. By including a single oscillator Sellmeier model for the high-energy absorption spectrum, closed-form expressions are obtained for the band-edge region refractive index. Both spectra are fully described in terms of a finite set of parameters that can be interpolated for all the important compound semiconductors. The refractive index spectra are extended beyond the band-gap energy and are in excellent agreement with the available experimental data. Our new model makes accurate modeling possible for devices such as electroabsorption and electrorefraction modulators.

Strahlwäscher sind durch Ihre Fluiddynamik gekennzeichnet, was eine detaillierte Simulation erschwert. Es konnte gezeigt werden, dass die in der Literatur üblichen empirischen Ansätze aufgrund Ihrer Vereinfachungen den Prozess nur ungenau beschreiben und daher nur für eingeschränkte Bedingungen gelten. Die für die Auslegung von Strahlwäschern relevanten Größen, die erreichbare Pressung und die Stoffaustauschfläche, für beliebige Betriebspunkte wurden in dieser Arbeit durch eine dreidimensionale CFD Simulation berechnet. Es wurden entsprechende Unterprogramme implementiert, um den Stoffübergang im Strahlwäscher zu berechnen. Die chemische Absorption wurde sowohl für die Tropfen als auch für den sich ausbildenden Wandfilm berechnet und als Senke an die Gasphase zurückgegeben. Die Tropfengröße und der Sprühwinkel haben einen essentiellen Einfluss auf die Strömungsverhältnisse im Strahlwäscher. Diese, im wesentlichen von der Düse abhängigen Größen, wurden experimentell mit der Phasen-Doppler-Anemometrie bestimmt. Die Simulationsergebnisse wurden durch Versuche in einer Technikumsanlage verifiziert.

<p>This thesis represents a quantum chemical treatise ofvarious types of interactions between radiation and molecularsystems, with special emphasis on the nonlinear opticalprocesses of Multi-Photon Absorption and Excited StateAbsorption. Excitation energies, transition dipole moments,two-photon and three-photon tensor elements have beencalculated from different approaches; density functional theoryand<i>ab-initio</i>theory, employing different orders ofcorrelation treatment with the purpose to provide accuratevalues as well as evaluate the quality of the lower ordermethods. A combined study of the Multi-Photon Absorption andExcited State Absorption processes is motivated partly becausethey both contribute to the total optical response of a systemsubjected to intense radiation, but also because of theirconnection through so-called sum-over-states expressions. Thelatter feature is exploited in a generalized few-states model,which incorporates the polarization of the light and thedirections of the transition dipole moments constructing anexcitation channel, which thereby enables a more comprehensivecomparison of the attained transition dipole moments withexperimental data. Moreover, by decomposing a complex nonlinearresponse process such as Two-Photon Absorption into moreintuitive quantities, generalized few-states models may alsoenable a more elaborate interpretation of computed orexperimental results from which guidelines can be extracted inorder to control or optimize the property of interest. Ageneral conclusion originating from these models is that thetransition dipole moments in an excitation channel should bealigned in order to maximize the Two-Photon Absorptionprobability. The computational framework employed is responsetheory which through the response functions (linear, quadratic,cubic) offers alternative routes for evaluating the propertiesin focus; either directly and untruncated through the singleresidue of the quadratic or cubic response func- tions orthrough various schemes of truncated sum-over-statesexpressions where the key ingredients, transition dipolemoments, can be identified from the single residue of thelinear response function and double residue of the quadraticresponse function. The range of systems treated in the thesisstretches from diatomics, such as carbon monoxide and lithiumhydride, via small to large fundamental organic molecules, suchas formaldehyde, tetrazine and the trans-polyenes, to largechro- mophores, such as<i>trans</i>-stilbene, cumulenes, dithienothiophene,paracyclophane and organo-metallic systems, such as theplatinum(II)ethynyl compounds.</p>