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O'Neil, Alanna R.Chemiluminescence and High Speed Imaging of Reacting Film Cooling Layers
Master of Science (M.S.), University of Dayton, 2011, Aerospace Engineering

The demand for more efficient and compact gas turbine engines has resulted in an increase in the operating temperatures and pressures and a decrease in combustor weight and size. These advances may result in incomplete combustion products entering the turbine section. The products can react with the air intended to cool the turbine vanes, and the resulting flame can cause damage to the engine. This study reports chemiluminescence measurements of flames and correlates these to heat release rate and the measured heat flux to a surface. To accomplish this, fuel rich combustion products are generated in a well-stirred reactor. The flow of products is directed over a flat plate with cooling air jets normal to the flow. Chemiluminescence data of the flames is obtained, along with high speed images, and temperature measurements of the flow inside the test section. Three film cooling geometries are studied: normal holes, fan shaped holes, and slot. Measurements are acquired at three equivalence ratios (1.3, 1.4, and 1.5) at three different blowing ratios (M = 1, 4, and 7).

It is found that the rate of heat release from the flame does not always trend the same as the heat transfer to the surface. It is also seen that a large reaction region does not always equate to high heat flux to the surface. If enough cooling air is present the surface is protected from the heat released from the flame.

Committee:

Dilip Ballal, PhD (Committee Chair); Scott Stouffer, PhD (Committee Member); David Blunck, PhD (Committee Member); Sukh Sidhu, PhD (Committee Member)

Subjects:

Aerospace Engineering

Keywords:

Film Cooling; Chemiluminescence; Reacting Boundary Layers; Flames; Image Analysis;

Kai, JunhaiProtein Lab-on-a-Chips on Polyer Substrates for Point-of-Care Testing (POCT) of Cardiac Biomarkers
PhD, University of Cincinnati, 2006, Engineering : Electrical Engineering

Cardiac disease is the major cause of death in patients with end-stage renal disease, accounting for about 40% of all deaths. Cardiovascular diseases account for a significant number of mortalities in the United States especially in the 50 – 65 age range. The fast growing numbers of such patients generate great demand for a commercially available lab-on-a-chip which is able to carry out not only fast, reliable, and accurate measurements but also in portable or disposable format at low cost.

In this research, a disposable protein lab-on-a-chip on a Cyclic-Olefin Copolymer (COC) is designed, fabricated and calibrated for monitoring human cardiac biomarkers. The multi-analyte protein lab-on-a-chip is able to perform rapid and accurate measurement of multiple cardiac biomarkers in human serum, such as CRP, Myoglobin, c-Tnl and BNP. By integration into a portable analyzer system, point-of-care testing (POCT) of cardiac biomarker measurement can be realized.

Comparing with commercially available cardiac biomarker diagnostic systems, this work mainly focuses on an inexpensive platform for disposable biochip applied for multi-analyte point-of-care testing. Many novel methods and technologies are then developed and extensively tested such as low-cost polymer fabrication process and self-spotting antibody patterning.

The proposed protein lab-on-a-chip will be able to measure multiple types of cardiac biomarkers in human serum, such as CRP, Myoglobin, c-Tnl and BNP. In the proposed protein lab-on-a-chip, fluorescence and chemiluminescence based solid phase immunoassay techniques will be applied for sensing. In this work, multiple parameters that can affect cardiac biomarker immunoassay performances in protein lab-on-a-chip are extensively studied and used for computer-based simulation. The protein lab-on-a-chip configuration is then characterized and optimized based on the simulation and experimental results. By integration into a portable optical detection system and an automatic microfluidic control system, point-of-care testing of human cardiac biomarkers can be realized. In addition, by adopting different types of antibodies, the proposed protein lab-on-a-chip also can be easily extended to the detection of other biomarkers and proteins for clinical diagnostics.

Committee:

Dr. Chong Ahn (Advisor)

Keywords:

Lab-on-a-chip; Cardiac biomarker; multi-analyte; Protein chip; Chemiluminescence; immunoassay; BioMEMS; Polymer microfabrication

Manos, Dennis MichaelCrossed-beam chemiluminescence of group IIIb metals /
Doctor of Philosophy, The Ohio State University, 1976, Graduate School

Committee:

Not Provided (Other)

Subjects:

Chemistry

Keywords:

Chemiluminescence;Chemical reactions

ALLGOOD, DANIEL CLAYAN EXPERIMENTAL AND COMPUTATIONAL STUDY OF PULSE DETONATION ENGINES
PhD, University of Cincinnati, 2004, Engineering : Aerospace Engineering
Research studies investigating the performance optimization and fundamental physics of pulse detonation engines (PDE) were performed. Experimental and computational methods were developed and used in these studies. Four primary research tasks were established. The first research task was to obtain detailed measurements of a PDE exhaust plume for a variety of operating conditions and engine geometries. Shadowgraph visualizations in conjunction with OH* and CH* chemiluminescence imaging were performed. The PDE plume visualizations provided a means of studying the flowfield behavior associated with PDE ejectors and exhaust nozzles as well as providing explanations for the observed acoustic behavior of the PDE. The second research task was to quantify the thrust augmentation of PDE-ejectors. Significant losses in the ejector entrainment were observed when the ejector inlet was not of an aerodynamic shape. Performance measurements of axisymmetric PDE-ejector systems showed the thrust augmentation to be a strong function of the ejector length-to-diameter ratio, ejector axial placement and PDE fill-fraction. Peak thrust augmentation levels were recorded to be approximately 20% for a straight-ejector and 65% for a diverging-ejector. An increase in thrust augmentation was obtained with a reduction in fill-fraction. Performance measurements of PDE converging and diverging exhaust nozzles were also obtained at various operating conditions of the engine. At low fill-fractions, both converging and diverging exhaust nozzles were observed to adversely affect the PDE performance. At fill-fractions close to and greater than 1, the converging nozzles showed the best performance due to increased PDE blow-down time (maintaining PDE chamber pressure) and acceleration of the primarily subsonic exhaust flow. The fourth research task was to perform a detailed far-field study of PDE acoustics. The acoustic energy of the PDE blast-wave was observed to be highly directional. Very good agreement was obtained between the experimental data and model predictions for the radial decay in peak pressure as well as the characteristic times of the blast-wave pulses. Converging exhaust nozzles were observed to produce a global reduction in PDE noise, while diverging nozzles affected only the downstream noise.

Committee:

Dr. Ephraim Gutmark (Advisor)

Subjects:

Engineering, Aerospace

Keywords:

pulse detonation engine; detonation; nozzles; ejectors; acoustics; shadowgraph; blast waves; computational fluid dynamics; chemiluminescence

Zhang, WeiDevelopment of Photochemically Initiated Direct and Indirect Luminescence Detection Methods for Liquid Chromatography (LC) and Study of Aromatic Sulfonates and Phospholipids Using Reversed Phase Ion-Pair LC-Mass Spectrometry
Doctor of Philosophy, Miami University, 2003, Chemistry
The first project is development of a 5.5 µL spiral micro-flow chemiluminescence (CL) cell that allows the rapid mixing of CL reagent and analyte and simultaneous detection of the emitted light for flow injection (FI) using a 25 µL/min flow rate for luminol and a 50 µL/min buffer carrier flow rate. The detection limit of 1.5 µM achieved by using a spiral flow cell is 24 times lower than that obtained from a conventional FI system with a premixing tee and a straight 12 µL flow cell. This luminol FI method is applied to the enzymatic determination of L-lactate from 5–50 µM using polyethyleneglycol-stablized lactate oxidase. The second project is development of a quinine-sensitized photo-oxidation and quenched CL detection method for phenols using FI and LC. This method is based on the decrease of light emission from the luminol CL reaction due to the photo-oxidation of phenols that scavenge the photogenerated reactive oxygen species. On-line photo-oxidation is achieved using a coil photo-reactor made from FEP tubing coiled around a mercury UV lamp. This method is applied for the FI determination of ten phenolic compounds, mostly nitro- and chloro-phenols, and the LC determination of phenol, 4-nitrophenol and 4-chlorophenol with detection limits of about 1 µM. The third project is development of an indirect fluorescence (FL) detection method via the shielding effect on the UV-photolysis of 2-phenylbenzimidazole-5-sulfonic acid (PBSA). Compounds that have a strong UV absorbance at 217 nm and/or are reactive toward the photogenerated oxygen species can possess such a shielding effect. This method is applied for both the FI determination of thirteen aromatic compounds, mostly non-fluorescent nitro compounds, and the LC determination of salicylate, nitrofurantoin, 4-nitroaniline, 2-nitrophenol, and 4-nitrophenol with detection limits of about 0.2 µM. The fourth project is separation of ionic organic compounds by reversed phase ion-pair LC with MS detection. tert-Octylamine (TOA) is studied as a new more volatile ion-pairing agent for separation of aromatic sulfonates. The separation results are compared with those obtained from NH4OH, dihexylamine, and tri-n-butylamine. TOA is the preferred ion-pairing agent as compared to NH4OH for the gradient separation of phospholipids.

Committee:

Neil Danielson (Advisor)

Subjects:

Chemistry, Analytical

Keywords:

Spiral micro-flow cell; Flow injection; Luminol chemiluminescence; Hydrogen peroxide; L-lactate; photo-oxidation; Quinine; Photosensitizer; Phenols; Liquid chromatography; Indirect fluorescence detection; Shielding effect; Nitro aromatic compounds

Keshav, SaurabhUsing Plasmas for High-Speed Flow Control and Combustion Control
Doctor of Philosophy, The Ohio State University, 2008, Mechanical Engineering
Experiments on characterization of Localized Arc Filament Plasma Actuators used for high-speed flow control, as well as experimental studies of chemiluminescence and chemi-ionization for flame emission and combustion control have been discussed. Pulsed DC and pulsed RF actuator discharge power measurements and plasma temperature measurements demonstrated that rapid localized heating, at a rate of 1000 degrees C / 10 μs, can be achieved at low time-averaged actuator powers, 10-20 W for 10% duty cycle. Kinetic modeling of a pulsed arc filament demonstrated formation of strong compression waves due to rapid localized heating, which have also been detected in the experiments. The effect of electrons in chemi-ionized supersonic flows of combustion products on flow emission is studied experimentally. For this, a stable ethylene/oxygen/argon flame is sustained in a combustion chamber at a stagnation pressure of P0=1 atm. Electron density in M=3 flow of combustion products has been measured using Thomson discharge. The results show that nearly all electrons can be removed from the flow by applying a moderate transverse electric field. No effect of electron removal on CH and C2 emission from the flow has been detected. Also, electron removal did not affect NO β band and CN violet band emission when nitric oxide was injected into the combustion product flow. Chemi-ionization current measured in the supersonic flows of combustion products has been used for feedback combustion control. The experiments showed that time-resolved chemi-ionization current is in good correlation with the visible emission (CH and C2 bands) in the combustor at unstable combustion conditions, and is nearly proportional to the equivalence ratio at stable combustion conditions. Chemi-ionization current signal from the combustion product flow has been used to control an actuator valve in the fuel delivery line and to maintain the equivalence ratio in the combustor at the desired level.

Committee:

Igor Adamovich, PhD (Advisor); Mohammad Samimy, PhD (Committee Member); Walter Lempert, PhD (Committee Member); William Rich, PhD (Committee Member); Vishwanath Subramaniam, PhD (Committee Member)

Subjects:

Aerospace Materials; Engineering; Mechanical Engineering

Keywords:

high-speed flow; repetitively pulsed plasmas; chemiluminescence; chemi-ionization; combustion control; rocket plume

Schwenz, Richard WilliamChemiluminescence from reaction of the group IIIa metals with halogen molecules.
Doctor of Philosophy, The Ohio State University, 1981, Graduate School

Committee:

Not Provided (Other)

Subjects:

Chemistry

Keywords:

Chemiluminescence;Halogens

LEE, SOOHYUNA POLYMER LAB-ON-A-CHIP FOR REVERSE TRANSCRIPTION (RT)-PCR FOR POINT-OF-CARE CLINICAL DIAGNOSTICS
PhD, University of Cincinnati, 2008, Engineering : Electrical Engineering

In this dissertation, a new polymer Reverse Transcription (RT)-Polymerase Chain Reaction (PCR) lab-on-a-chip (LOC) with embedded micro pinch-valves has been designed, fabricated and characterized for point-of-care testing (POCT) clinical diagnostics. In addition, a portable analyzer, which consists of an optical detection system and a non-contact infrared (IR) based temperature control system for RT-PCR process, has been developed and characterized as the analyzer monitoring for the developed RT-PCR LOC. The developed LOC and analyzer have been interfaced and optimized for performing the RT-PCR procedure and chemiluminescence assay in sequence, and then as a demonstration of clinical diagnostics Human Immunodeficiency Virus (HIV) for the early diagnostics of Acquired Immune Deficiency Syndrome (AIDS) has been successfully analyzed using the developed LOC and analyzer.

In the RT-PCR LOC, a new concept of the embedded micro pinch-valve has been proposed, fabricated and characterized as one of the key microfluidic components desired for the RT-PCR procedure. In the development of the embedded micro pinch-valve, a new sealing method using UV adhesive has been developed, which provides enough sealing required for the prevention of leakage at the high pressure developed during the PCR procedure. The developed embedded micro pinch-valve can possibly have numerous applications for the functional lab-on-a-chips which need to be integrated with on-chip microvalves.

Also, in the portable analyzer, a temperature control system and an optical detection system have been developed, assembled and fully characterized for the procedure control and optical detection of the RT-PCR LOC. In order to minimize the process time of RT-PCR, a non-contact IR heating method has been adopted for controlling the temperature on the RT-PCR chip. For the optical detection system, an extremely high sensitive photodiode with a high gain amplifier circuit with low noise has been used for detecting the chemiluminescence assay.

AIDS comes from infecting HIV (Human Immunodeficiency Virus), a syndrome where the immune system begins to fail, leading to many life-threatening infections. Since early diagnostics of the disease by indentifying HIV is essential for the treatment of the disease, the development of POCT clinical diagnostics near to the patients is very desirable. So, in this work, the developed RT-PCR LOC and analyzer has been applied for the detection of HIV in a POCT platform.

The developed RT-PCR LOC has been characterized first for both fluorescence and chemiluminescence assays in terms of sensitivity and adoptability with the portable analyzer. The analysis results obtained from the developed portable analyzer have shown an excellent performance comparable to those obtained from the conventional scanner, which ensures the developed RT-PCR LOC and portable analyzer as a promising POCT for clinical diagnostics.

In conclusion, in this research work, a new RT-PCR polymer lab-on-a-chip and its portable analyzer has been successfully developed and fully characterized for the POCT of clinical diagnostics, and then the developed RT-PCR LOC and analyzer has successfully performed the whole assay of HIV, envisaging the POCT of early diagnostics of AIDS.

Committee:

Chong Ahn, PhD (Committee Chair); Ian Papautsky, PhD (Committee Member); Paul Bishop, PhD (Committee Member); Joseph Nevin, PhD (Committee Member); Sung-Woo Kim, PhD (Committee Member)

Subjects:

Electrical Engineering

Keywords:

RT-PCR; Lab-on-a-Chip; Pinch Valve;Chemiluminescence Assay;HIV Diagnostics