The introduction of deep reactive ion etching (DRIE) technology has greatly expanded the accessible design space for microscopic systems. Structures that are hundreds of micrometers tall with aspect ratios of 40:1, heretofore impossible, can now be achieved. However, this technology is primarily a forming technology, sculpting structures from a substrate. This work seeks to complement deep reactive ion etching by developing an electrical isolation technology to enable electro-mechanical function in these new deep reactive ion etched structures. The objective of the research is twofold. The first is to develop and characterize an electrical isolation technology for DRIE, single crystal silicon (SCS) micro-electro-mechanical systems (MEMS) using temperature gradient zone melting (TGZM) of aluminum junctions for diodic isolation. The second is to demonstrate the utility of this electrical isolation technology in the design, simulation, fabrication, and testing of a MEMS device, i.e. a micro-gyroscope, in such a way that the benefits from junction isolated, deep reactive ion etched, single crystal silicon devices are preserved.

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In the U.S. Chemical Safety and Hazard Investigation Board (CSB) report, Improving Reactive Hazard Management, there are 37 out of 167 accidents, which occurred in a storage tank or a storage area. This fact demonstrates that thermal runaway problems in chemical storage processes have not been give enough attention. Hydroxylamine Nitrate (HAN) is an important member of the hydroxylamine compound family and its diluted aqueous solution is widely used in the nuclear industry for equipment decontamination. It is also used as a solid or aqueous propellant. Due to its instability and autocatalytic behavior, it has been involved in several incidents at the Hanford and Savannah River Sites (SRS). Much research has been conducted on HAN in different areas, such as combustion mechanism, decomposition mechanism, and runaway behavior. However, the autocatalytic behavior of HAN at runaway stage has not been fully addressed due to its highly exothermic and rapid decomposition behavior. This work focuses on extracting its autocatalytic kinetics mechanism and studying its critical behavior from adiabatic calorimetry measurements. The lumped autocatalytic kinetics model, the associated model parameters and HAN critical condition are determined for the first time. The contamination effect of iron ions and nitric acid on diluted hydroxylamine nitrate solution is also studied. This work also identified the safe storage conditions for a small quantity HAN diluted solution with thermal explosion theory. Computational Fluid Dynamics (CFD) was used to further study the influence of natural convection and system scale on the critical behavior for a large quantity of chemical and thus proposed the practical storage guidelines for industrial practice.

Although it has been shown that clean perforation tunnels facilitate the evolution of a single, deeper-penetrating wormhole, there are no reported applications of reactive shaped charges in carbonates prior to acid stimulation. The present study was instigated to evaluate the impact of reactive charges on acid wormholing in representative carbonate cores. A set of oil-saturated Indiana limestone and cream chalk cores have been perforated under simulated downhole conditions using either a conventional or a reactive shaped charge of equal explosive load. After CT scanning to eliminate outlying perforations affected by rock property anomalies, the set of cores were subjected to identical acid injection treatments representative of typical carbonate reservoir stimulations. Time to breakthrough and effluent chemistry were both analyzed and recorded. Finally, post-stimulation CT scans were used to evaluate wormhole morphology. The laboratory experiments showed that reactive charges provide wider perforation tunnels with higher injectivity, which is beneficial for any type of stimulation job. Higher injectivity tunnels help to propagate more dominant and straighter wormholes resulting in less acid to break through the cores. This technology has a significant potential when perforating tight formations or heterogeneous intervals, where obtaining clean tunnels with conventional perforators is most challenging. Further research work needs to be done to evaluate if the difference in acid volume to breakthrough observed in the experiments would have a major impact in the field.

Reactive power, denoted as volt-ampere reactive (VARs), is fundamental to ac power systems and is due to the complex impedance of the loads and transmission lines. It has several undesirable consequences which include increased transmission loss, reduction of power transfer capability, and the potential for the onset of system-wide voltage instability, if not properly compensated and controlled. Reactive power compensation is a technique used to manage and control reactive power in the ac network by supplying or consuming VARs from points near the loads or along the transmission lines. Load compensation is aimed at applying power factor correction techniques directly at the loads by locally supplying VARs. Typical loads such as motors and other inductive devices operate with lagging power factor and consume VARs; compensation techniques have traditionally employed capacitor banks to supply the required VARs. However, capacitors are known to have reliability problems with both catastrophic failure modes and wear-out mechanisms. Thus, they require constant monitoring and periodic replacement, which greatly increases the cost of traditional load compensation techniques. This thesis proposes a reactive power load compensator that uses inductors (chokes) instead of capacitors to supply reactive power to support the load. Chokes are regarded as robust and rugged elements; but, they operate with lagging power factor and thus consume VARs instead of generating VARs like capacitors. A matrix converter interfaces the chokes to the ac network. The matrix converter is controlled using the Venturini modulation method which can enable the converter to exhibit a current phase reversal property. So, although the inductors draw lagging currents from the output of the converter, the converter actually draws leading currents from the ac network. Thus, with the proposed compensation technique, lagging power factor loads can be compensated without using capacitor banks. The detailed operation of the matrix converter and the Venturini modulation method are examined in the thesis. The application of the converter to the proposed load compensation technique is analyzed. Simulations of the system in the MATLAB and PSIM environments are presented that support the analysis. A digital implementation of control signals for the converter is developed which demonstrates the practical feasibility of the proposed technique. The simulation and hardware results have shown the proposed compensator to be a promising and effective solution to the reliability issues of capacitor-based load-side VAR compensation techniques.

Transparent conductive aluminum-doped zinc oxide(AZO) thin films were synthesized by reactive RF magnetron co-sputtering system with metallic zinc and aluminum targets under oxygen atmosphere. Systematic study on the fixed sputtering power of the Zinc target (PZn) and the variation of the sputtering power of the Aluminum target (PAl) on structural, electrical and optical properties of AZO thin film was mainly investigated in this work. We found that the microstructure of AZO films would be obviously transformed from rice-like crystalline structure to nanocrystalline (nano-column) structure with the increasing of the sputtering power of the Aluminum target (PAl) . Nanocrystalline AZO films were formed at the specific sputtering power ratio of metallic targets (PAl/ PZn=1) . X-ray diffraction (XRD) spectra revealed that nanocrystalline AZO films highly preferred c-axis orientation (002) was growth in perpendicular to the substrate. The optical refractive index (n) of nanocrystalline AZO films had significantly lower values than others of microstructure AZO films, and this suggested the low optical dispersion in nano-column structure . Furthermore, the electronic properties of AZO films with the proper sputtering power of the Aluminum target (PAl) evidently improved under rapid temperature annealing (RTA) process. It suggested that both high annealing temperature(400¢J) and rapid cooling time(15min) are main factors to decrease the sheet resistances due to the maintenance of high temperature structural phase. The results of X-ray photoelectron spectroscopy (XPS) show that RTA process can decrease oxidized Al in order to decrease the sheet resistances.

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Although there had been some improvement of treatment results by the combination of concurrent chemoradiotherapy with esophagectomy, the overall prognosis for patients with esophageal cancer remained poor. Selection of optimal treatment strategy for individual patients would be improved by an objective biomarker that can predict prognosis accurately. The aim of this prospective study was to evaluate whether serum concentration of C-reactive protein (CRP) can be used as a prognostic factor to predict the survival of esophageal cancer patients treated with radiotherapy. Between Nov 2002 and July 2007, patients undergoing radiotherapy for newly diagnosed esophageal cancer were eligible for inclusion into this study. Serum CRP concentration was measured prospectively before the initiation of treatment. The relationship between the serum CRP levels and clinicopathological parameters were analyzed retrospectively. The prognosis factors of esophageal cancer were statistically determined. A total of 123 patients consisting of 120 males and 3 females were enrolled in this study. 81 patients (65.9%) had high CRP levels (greater than 5 mg/L). Patients with CRP levels higher than 5 mg/L had a shorter overall survival (P < 0.001). The 2-year survival was 78.4% for patients with CRP < 5 mg/L compared with 7.8% with CRP¡Ù5 mg/L. Hypoalbuminemia (albumin< 3.5g/dL) was significantly related to shorter survival in univariate analysis. Multivariate analysis demonstrated that higher serum CRP concentration and hypoalbuminemia were both independent prognostic factors for esophageal cancer. Pretreatment serum CRP and albumin levels are easily measurable biomarkers and are significant prognostic factors for esophageal cancer. They can be used in combination with the conventional staging system to predict survival and stratify patients with esophageal cancer treated with radiotherapy more accurately.

Reactive Sputtering is a widely used technique in processing of thin compound films. Such films can be sputtered from metal targets, which are comparatively cost efficient. Also the fact that sputtering from metal targets can ccur in the dc mode reduces the cost of the sputtering equipment. To keep the deposition process stable, its necessary to know the effects of target poisoning including its hyteresis behavior. The aim of this work was to nvestigate the evolution of reactive gas coverage on a titanium magnetron target surface, by real time, in-situ ion beam analysis during magnetron sputtering. A cylindrical 2 inch magnetron was used for reactive sputtering of TiN. It was operated in an Ar/N2 gas mixture at achamber pressure of about 3∙10-3 mbar. The argon/nitrogen flux ratio was variated between 0 and 20%. The nitrogen concentration on the target was determinated using the 14N(d, α)12C, nuclear reaction at a deuterium beam energy of 1.8 MeV. Depending on the adjusted nitrogen flow the target incorporation varies between 0 and about 1∙1016 N∙cm-2. Further the expected hysteresis behaviour ofnitrogen partial pressure, target voltage and nitrogen concentration at increasing/decreasing nitrogen gas flow is confirmed. The lateral distribution of nitrogen was measured across the diameter of target surface. In the zone of higher erosion (the \"race track\") the nitrogen concentration is 50% lower than in the middle or the edge of the target. A deposition zone in the center of the target could not be detected. By increasing the nitrogen flow into the chamber a saturation in nitrogen content in the target was found at an Ar/N2 flow ratio of about 10%. Assuming nitrogen implantation with a depth of 2.5 nm under the influence of typical target voltage during magnetron sputtering, this saturation is at a concentration value where stoichiomtric TiN is formed. Within the precision of the measurements, a mobile fraction of nitrogen could not determined. The concentration in the target remains unchanged after switching off the magnetron.

This paper presents the result of dyeing solution coagulation with the use of ferrous ammonium sulfate hexah ydrate (FAS). The examined solution contains two reactive dyes: Black 5 and Blue 19. It has been shown that the efficiency of the dye removal depends on the type of dye, coagulation dosage and the initial pH. Our result showed that the increase of initial pH up to 12 enhanced the color removal efficiency; the FAS dose was 280 ml (Black 5) and 180 mg/l (Blue 19) at slow mixing time (15 min), agitation speed 60 rpm, and the initial dye concentration should be 50 and 100 mg/L for Black 5 and Blue 19, respectively. / Chất keo tụ sắt (II) amoni sulfate (FAS) được sử dụng khử màu của hai màu nhuộm hoạt tính phổbiến (Blue 19 và Black 5). Kết quả cho thấy, quá trình keo tụ bịảnh hưởng nhiều bởi loại màu nhuộm, nồng độ chất keo tụ và pH của dung dịch đầu vào. Với nồng độ FAS 280 mg/l (Black 5) và 180 mg/l (Blue 19), pH đầu vào dung dịch khoảng 12, thời gian phản ứng 15 phút, tốc độ khuấy 60 vòng/phút ứng với nồng độ màu Black 50 mg/L và blue 100 mg/L dung dịch gần như mất màu hoàn toàn.