The objective of this research is to develop and test a new concept for predicting permeability from routine rock properties. First, we develop a model predicting permeability as a function of capillary pressure. Our model, which is based on the work by Purcell, Burdine and Wyllie and Gardner models, is given by: (Equation 1 - See PDF) Combining the previous equation and the Brooks and Corey model for capillary pressure, we obtain: (Equation 2 - See PDF) The correlation given by this equation could yield permeability from capillary pressure (and vice-versa). This model also has potential extensions to relative permeability (i.e., the Brooks and Corey relative permeability functions) - which should make correlations based on porosity, permeability, and irreducible saturation general tools for reservoir engineering problems where relative permeability data are not available. Our study is validated with a large range/variety of core samples in order to provide a representative data sample over several orders of magnitude in permeability. Rock permeabilities in our data set range from 0.04 to 8700 md, while porosities range from 0.3 to 34 percent. Our correlation appears to be valid for both sandstone and carbonate lithologies.

An algorithm was developed to control the partial pressures of N2, O2, and CO2 in a gas mixing tank. The gases were premixed before being introduced into the low pressure Mars Dome. As an attempt to reduce the effects of pressure, the number of moles of the component gases was calculated and used to determine when gases needed to be added to the system or when gas concentrations needed to be diluted. There were two trial runs during each of the two experiments carried out. The total pressures in both the mixing tank and the Mars Dome remained within their limits of constraint during both trials. For the mixing tank, the pressure was maintained between 170kPa and 180kPa with a setpoint of 175kPa. Gas composition was evaluated at 67kPa and 33kPa in the Mars Dome. Again the pressure remained within its range of ±5kPa of its setpoint. Adequate control of the partial pressures of N2, and O2 were achieved in the mixing tank and the Mars Dome. With respect to the control of CO2, the algorithm was unable to maintain the partial pressure within the operational limits specified. The tendency was for CO2 to linger above its setpoint. Moreover, at 33kPa the CO2 sensor in the Mars Dome began to reflect a lower concentration of CO2 in the system than what was reported by the gas chromatograph or the CO2 sensor in the mixing tank. While sufficient control of the partial pressures was achieved, there are modifications to be made that should further tighten the control limits of the system. Such modifications include recalibrating the sensors in the system and adjusting gas flow rates.

The economics of drilling offshore wells is important as we drill more wells in deeper water. Drilling-related problems, including stuck pipe, lost circulation, and excessive mud cost, show the need for better drilling technology. If we can solve these problems, the economics of drilling the wells will improve, thus enabling the industry to drill wells that were previously uneconomical. Managed pressure drilling (MPD) is a new technology that enables a driller to more precisely control annular pressures in the wellbore to prevent these drillingrelated problems. This paper traces the history of MPD, showing how different techniques can reduce drilling problems. MPD improves the economics of drilling wells by reducing drilling problems. Further economic studies are necessary to determine exactly how much cost savings MPD can provide in certain situation. Furter research is also necessary on the various MPD techniques to increase their effectiveness.

Characteristics of emitters under low pressure are essential for designing drip irrigation systems. Low pressure data for drip emitters are not available from manufacturers. A laboratory test was conducted to evaluate the performance of five types of newly manufactured drip tapes, especially under a low pressure distribution system. The five drip products that were tested were (i) Toro Drip in PC (PCS 1810-18- 100), (ii) T-Tape (TT15-1245-0100), (iii) Mister_LS (MLD-HDT100), (iv) Mister_PS (MLD-1PC 25), and (v) Netafim (Techline CV 560 050). Drip tapes tested in this study have design discharge rates of 4.00 L/hr @ 206.84 Kpa (1.06 gph @ 30 psi), 1.02 L/hr @ 55.16 Kpa (0.27 gph @ 8 psi), 3.785 L/hr @ 172.37 Kpa (1.00 gph @ 25 psi), 3.785 L/hr @172.37 Kpa (1.00 gph @ 25 psi), and 0.984 L/hr @ 206.84 Kpa (0.26 gph @ 20psi), respectively. All of them, except T-Tape, were pressure compensating (PC) emitters; the T-Tape was non-pressure compensating (NPC). For all products, except Toro, the emitter spacing was 0.305 m (12 inches) and for Toro, it was 0.46 m (18 inches). Mister_PS (MLD-1PC 25) was the point source (PS) emitter and all others were line source emitters. Drip products were tested with 15 different operating pressures ranging from 5.97 KPa (0.87 psi) to 344.74 KPa (50.00 psi). From an evaluation of 60 emitters from each product, the Toro brand showed an average uniformity coefficient (UC) of 91.24 %, with a coefficient of variation (Cv) of 0.06, T-Tape drip products showed an average UC of 96.63 % with a Cv of 0.04, Mister_ LS showed an average UC of 93.12 % with a Cv of 0.08, Mister_PS showed an average UC of 96.33 % with a Cv of 0.04, and Netafim showed an average UC of 97.92 % with a Cv of 0.02. Flow rate vs. pressure head (Q-H) curves were also developed for each drip emitter tested. From emitter exponent values it was observed that all of the pressure compensating (PC) products behaved like NPC emitters at low pressures, although they behaved like PC emitters under normal operating pressures. From statistical analysis, it was determined that except for Netafim product, all other tested products were effective under low operating pressures as were under high operating or recommended pressures. Netafim product had no emission under low pressures. Using the measured average emission rate and developed Q-H curves, the distribution uniformities of all products except Netafim were calculated under low pressure ranges of 5.97 KPa (0.87 psi) to 23.88 KPa (3.50 psi ) for different lengths of laterals and under 0%, 1%, 2%

This dissertation proposes a novel packaging methodology for micro-electro-mechanical systems (MEMS) based pressure sensors by using a patterned ultra-thick (150

The nucleus tractus solitarii (NTS) is the primary integrative center for baroreflex. NTS not only integrates convergent information from peripheral baroreceptors and higher blood pressure (BP) control centers in CNS but itself is the site of substantial modulation. Our previous studies demonstrated that microinjection of nicotine into the NTS decrease BP and heart rate (HR), which indicates nicotine plays cardiovascular modulatory role in the NTS. However, the mechanisms how nicotine modulate cardiovascular functions in the NTS remained unclear. The aim of this study was to investigate the molecular mechanisms of nicotine-induced depressor and bradycardic effects in the NTS. Male anesthetized Wistar-Kyoto rats, with or without intra-NTS nitric oxide synthase (NOS) inhibitors or ionotropic glutamate receptor inhibitors pretreatment, received intra-NTS nicotine microinjection. BP and HR were monitored. Besides, NTS with/without nicotine microinjection were dissected and subjected to immunoblotting and nitric oxide (NO) analysis. Our results demonstrated that NO analysis study revealed intra-NTS NO production elevated after nicotine microinjection. The depressor and bradycardic effects of intra-NTS nicotine microinjection were diminished by pretreatment of calmodulin inhibitor (W7, 0.33 nmol), non-specific NOS inhibitor (L-NAME, 33 nmol) and eNOS specific inhibitor (L-NIO, 6 nmol). The cardiovascular effects of nicotine were also attenuated by NMDA receptor inhibitor (MK801, 1 nmol), not by non-NMDA receptor inhibitor (NBQX, 10 pmol). Immunoblotting and immunohistochemical studies did not revealed nicotine induced eNOSS1177 phosphorylation in NTS. Using MEK inhibitor, PD98059, and nNOS specific inhibitor,Vinyl-L-NIO and 7-NI, there were no effect on the depressor and bradycardic effects of intra-NTS nicotine microinjection, and the phosphorylation of AktT473 was not induced by nicotine. Therefore, our results indicate that nicotine-induced depressor and bradycardic responses maybe mediated through activating eNOS by calmodulin and stimulating glutamate release in the NTS.

Thesis--Danmarks tekniske højskole.

Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2004. / Includes bibliographical references.

Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1930. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed March 10, 2010)

Thesis (Ph. D.)--University of Michigan, 1929. / Cover title. "By Marvin C. Rogers and Geo. Granger Brown."