Heat transfer data were taken for methanol and Freon-12 condensing inside a horizontal tube over considerable ranges of pressure, temperature driving force, liquid loading, and vapor velocity. A single mechanism for heat transfer could not explain the behavior of this and other data over the entire range of the variables. For condensation in a horizontal tube, three primary regions of flow are postulated: (1) semi-stratified flow (annular condensation and run-down superimposed on stratified flow), (2) laminar annular flow, and (3) turbulent annular flow. A semi-theoretical equation, NuPr-1/3=0.388 M1/6DGvm r/rv 1/21/4 is developed and shown to be applicable to both semi-stratified and laminar annular flow. Other equations must be used for turbulent annular flow.

This work has been divided into two parts. The first is concerned with methods of computation suitable for use with digital computers for distillation problems with one feed and two product streams. Two methods were investigated (although others have been employed and reported by many authors): The Lewis-Matheson method and a modified Thiele-Geddes method. These techniques differ in that one requires floating-point arithmetic, while the other does not. A comparison has been made illustrating the merits and faults of both methods. The second section presents the results of a number of computations. A correlating method suggested recently by Geddes was investigated, as well as the more familiar ones of Gilliland and Brown & Martin. An empirical correlation was developed after the suggestion of Geddes for the range 0.5⩽LV⩽1.0, 0<DF⩽0.5 . Further, the effect of both the number of plates and the reflux ratio has been examined.

A method has been investigated for measuring vapor-liquid equilibrium ratios, or K-values, of a solute distributed between a gas phase and a non-volatile liquid phase. A gas-liquid partition chromatographic technique is employed in which an inert, porous fire-brick is impregnated with the liquid phase, and the resulting liquid-containing solid is packed into a tube. The gas phase is flowed through the tube, and the solute of interest is eluted through the tube by the flowing gas phase. The data taken for the solute elution process is then related to the K-value of this solute in the vapor-liquid system maintained in the column. A previous mathematical solution describing the chromatographic elution process for a one component elution gas and which may be used to relate K-values to retention times for the solute at infinite dilution in the vapor-liquid equilibrium system is reviewed and expanded to include the effect of elution gas solubility in the liquid phase. A new mathematical solution is presented relating K-values to retention times for the case of a solute being eluted by a binary elution gas mixture composed of components soluble in the liquid phase. This solution covers the case of the solute sample being one of the components of the elution gas, in which the calculated K-values would be for the solute present at some finite composition in the system, and the case of the solute not being initially present in the elution gas, in which case the calculated K-value would be for the solute at infinite dilution in the vapor-liquid equilibrium system. Data were taken for ethane, propane, and n-butane solutes at infinite dilution in the methane-n-decane system at 160, 70, 40, 0, and -20°F from 20--2000 psia; for propane at infinite dilution in n-hexadecane at 70°F and 20--225 psia; and propane in the system methane-propane-n-decane at 40°F from 20--460 psia. The chromatographically determined K-values for n-butane at infinite dilution in methane-n-decane were compared over portions of the 40 and 160°F isotherms with published static equilibrium values and found in agreement. Data for all the solute isotherms were compared at atmospheric pressure with the results of the Bronsted-Koefed relation for predicting activity coefficients, and, again, close agreement was found. The applicability of the chromatographic method for determining freezing points was investigated, and the solid-liquid-gas line for the methane-decane system was measured.

The purpose of this investigation was to study the effect of physical properties and system dimensions on the mass transfer between a gas bubble and the parent liquid for the case of stagnant liquid. The study was divided into two parts; (1) the effect of these variables on the bubbling and (2) the effect of these variables on the mass transfer. The bubbling data were found to correlate to within 25% on a dimensionless plot. For Reynolds numbers above 100 the resulting equation is: fDg 1/2 mmH2O 0.05=0.27Re 0.06 For the three orifices which produced similar results the same plot correlated the data to within 12%. The equation for the data for Re above 1000 is: fDg 1/2 mmH2O 0.05=0.22Re 0.06 A mechanism for the formation of the bubbles based on the break-up of a jet is proposed. On the basis of this mechanism the shape and break point in the curve of frequency versus orifice velocity may be predicted. In the mass transfer study the approach to equilibrium was above 90% for the systems studied. This was found to be independent of the physical properties and system dimensions. It is shown that this result is predicted by the penetration theory. This theory is applied to an operating column.

An equivalent continuum approach was used to model the heat transfer in the array of channels of a non-adiabatic monolith reactor. The equivalent solid thermal conductivity in the transverse direction was derived for different cross-sectional geometries of the channels. The partial differential equations modeling the heat and mass transfer in a non-adiabatic reactor were solved numerically. The combined global collocation and collocation on finite element method was used to solve for the steady state solutions. And the backward finite difference method with predictor-corrector modification was added to solve for the time dependent solutions. Simulation results for exothermic and endothermic reactions are presented for ceramic and metallic monolith supports. The effects of channel geometry, channel density, wall thickness, reactor length, inlet fluid temperature and concentration were studied. Results showed that monoliths with triangular channels, higher channel density, thinner wall and longer length gave higher overall conversion for carbon monoxide oxidation. The effect of hydrogen on carbon monoxide oxidation was studied. No multiplicity was found. The simulation results for monolith converter with non-uniform flow qualitively confirmed the experimental observations of others' work.

The design of artificial genetic networks constitutes a powerful tool to regulate cellular physiology. Simple regulatory structures comprised of a few interacting genes can be assembled to engineer desirable phenotypes and control the biosynthesis of end products of biomedical and/or biotechnological interest. This doctoral thesis has focused on the in silico design of artificial genetic networks to drive the biosynthesis of a specific product of biotechnological interest, namely, PHA copolymer chains with desirable structures. In order to understand this complex process, a mathematical model was developed to describe the coupling between the dynamics of polymer and monomer formation and those of the genetic networks. The modeling studies have focused on the utilization of two synthetic networks, known as the genetic toggle and repressilator. The results indicate that the bistable toggle allows regulating the monomer composition of PHA copolymers. The use of the repressilator offers a higher level of control, as it enables the synthesis of PHA block copolymers with different length and composition of each of the blocks that comprise the chains. Additional computational studies have revealed the possibility to achieve superior performance than that of the repressilator, through the design of a novel genetic network that exhibits oscillatory dynamics with minimal overlap amongst gene expression levels. The oscillations were also found to be robust to stochastic fluctuations. Finally, an existing mathematical model was modified to explain the discrepancy of the original repressilator model with experimental data. The modeling studies support the hypothesis that non-specific interactions may also be present in addition to the original three promoter-repressor interactions, which the repressilator was designed to include.

Phototherapy is a non-intensive, selective, and simple method for treating diseases such as cancer. It has fewer side effects and can be more affordable than traditional treatments. There is a great interest in near-infrared light (NIR) because this radiation can penetrate deeper into biological tissue at a wide range of wavelengths. Indocyanine green (ICG) is a photosensitizer that absorbs and fluoresces in NIR range, and thus has been used for clinical imaging and diagnostics for more than 20 years. ICG has been found useful in light-based treatment through the generation of singlet oxygen or heat. However, ICG binds non-specifically to plasma proteins, has a short residence time in the blood stream, and has poor thermal stability and photo stability in aqueous solution. Encapsulation of ICG is a useful approach to address these limitations. The objectives of this research were to understand the mechanism of nanoparticle (NP) assembly and to apply it in ICG encapsulation. This simple procedure involves combining solutions of poly(allylamine hydrochloride) (PAH) and phosphate ions, adding an ICG solution, and finally, adding a silica nanoparticle(NP) sol. ICG was encapsulated into PAH/phosphate/silica capsules with loadings up to 23 wt%, much higher than other reported materials. The encapsulated ICG was found to have similar photothermal heating capabilities as the unencapsulated ICG. Silica NPs were replaced successfully by epidermal growth factor receptor (EGFR) antibody biomolecules, which could be regarded as biological NPs. The binding specificity of these antibody-displayed ICG-containing capsules was tested in cancer cells. Cell specificity and photothermal effect were demonstrated using 1483 cells and NIR irradiation (808 nm). Finally, the introduction of magnetic functionality was explored by replacing silica NPs with Fe3 O4 NPs. Magnetic response can potentially enhance delivery efficiency due to the influence of an external magnetic field. The capsules were found to noticeably change the ICG biodistribution in white female mice via intravenous injection. ICG was found to accumulate more in lungs when ICG was encapsulated. 2% increase of ICG percentage (as capsules) in the blood was observed at 2.5 min in the presence of an external magnetic field (0.03 Tesla) placed under the mouse tail where the ICG-capsules were injected.

This thesis improves the understanding of the Alkaline Surfactant Polymer (ASP) enhanced oil recovery process in order to optimize the ASP operational strategy. The conventional oil recovery methods leave large amounts of oil in the reservoir. ASP process is considered as a promising method for enhanced oil recovery. This dissertation reveals the ASP characteristics by using phase behavior, interfacial tension, surfactant consumption and numerical simulation techniques. The flooding experiments that I performed show that my ASP strategies successfully recover the oil trapped after waterflooding. The optimal salinity varies when either synthetic surfactant concentration or Water Oil Ratio (WOR) changes in ASP system. In this thesis, these results could be collapsed to a single curve for each synthetic surfactant/crude oil combination in which the optimal salinity depends only on the molar ratio of natural soap to synthetic surfactant, or soap fraction of total soap plus surfactant. The ASP system studied here has a much wider low IFT region (< 0.01 mN/m) than the system without alkali. In much of the Winsor I region where an oil-in-water microemulsion coexists with excess oil, a second surfactant-containing phase was seen to exist in colloidal form. This colloidal dispersion plays an important role in reaching the ultra-low tension. A new protocol, which significantly reduces the time that is required to reach equilibrium, is developed to assure that enough of the dispersed material is initially present to achieve low tensions but not so much as to obscure the oil drop during IFT measurements. Surfactant retention is one of the most significant barriers to the commercial application of ASP. It was found that Na2CO3 but not NaOH or Na2SO4, can substantially reduce adsorption of anionic surfactants on carbonate formations, especially at low salinities. A one-dimensional numerical simulator was developed to model the ASP process. By calculating transport of water, oil, surfactant, soap, salt, alkali and polymer, the simulations show that a gradient in soap-to-surfactant ratio develops with conditions shifting from over-optimum ahead of the displacement front to under-optimum behind the displacement front. This gradient makes the process robust and permits injection at conditions well below optimal salinity of the synthetic surfactant, thereby reducing adsorption and improving compatibility with polymer. More than 95% of waterflood residual oil was recovered in ASP sand pack experiments at ambient temperature with a slug containing a partially hydrolyzed polyacrylamide polymer and only 0.2 wt% of a particular anionic surfactant blend. The simulator predicts recovery curves in agreement with those found in the flooding experiments.

Microarrays have found widespread use for probing genomic and proteomic functions. These systems consist of a purposefully spotted microscopic slide of different biological samples (the microarray), a sub-milliliter solution volume containing target molecules of interest, and a coverslip to contain and spread the solution over the microarray surface. Incubation times for the target solution with the microarray can be as long as a day to allow binding of target molecules to probes on the array surface. These times are limited by the reliance on diffusional processes for transport within this thin-film geometry. This thesis describes various approaches for providing solution movement and mixing within this confined geometry by employing functionalized magnetite nanoparticles that are included within the target solution and an external applied magnetic field that together provide mixing within the microarray chamber. The effects of particle size, the concentration, the magnetic path and its movement have each been investigated, resulting in an optimization of accelerated mixing within the chamber. The nanoparticles used in this study were prepared to include surface functional groups to make them non-interacting with the microarray surface or toward target molecules in solution. They are readily removed from the system during a rinsing step prior to reading of a microarray. The approach of mixing by magnetic nanoparticles accelerated timescales for microarray experiments and also improved quality of data sets.

New down-hole nuclear magnetic resonance (NMR) measurement and interpretation techniques have substantially improved fluid and reservoir characterization. These techniques take advantage of the magnetic field gradient of the logging tools to make diffusion sensitive NMR measurements. In this work, new NMR pulse sequences called "diffusion-editing" (DE) are used to measure diffusivity and relaxation times for a variety of samples. We use a new inversion technique to obtain two-dimensional maps of diffusivity and relaxation times, and propose new interpretation approaches for these maps. Two DE NMR pulse sequences are of particular interest. First is the CPMG-DE Pulse sequence, based on the Carr-Purcell-Meiboom-Gill pulse sequence in a magnetic field gradient. Results presented here demonstrate that CPMG-DE measurements can be used to determine the saturation of partially saturated samples, detect wettability change, and observe the presence of internal field gradients or restricted diffusion. The second DE sequence of interest is PFG-SE DE, based on the pulse field gradient stimulated echo (PFG-SE) sequence. The PFG-SE DE sequence is particularly well suited for analyzing restricted diffusion, which occurs when the spins are prevented from diffusing freely by the presence of confinement such as pore walls. The interpretation of pore-size distributions from PFG-SE DE measurements can be simplified by approximating the pore network as a system of spheres of varying sizes. A procedure is developed for determining the optimal parameters for measuring spheres of a selected size. A technique for combining the sensitive portions of multiple measurements using masks is also developed. Experiments are performed on grain packs, vuggy carbonates, and emulsions. In most cases, the range of length scales the system is sensitive to is too narrow using the available range of gradients to provide interesting information about the systems, but in the case of emulsions the results are positive when evaluating droplet size distributions.