Pediococcus cerevisiae, Lactobacillus casei, Lactobacillus plantarum,
Leuconostoc mesenteroides, Lactococcus diacetylactis Bifidobacterium
bifidum, Leuconostoc oenos, and mixed cultures of Propionibacterium
shermanii and P. cerevisiae were used to ferment cucumber juice brine
(CJB) at 22-26°C for 1.5 months. Sugar utilization ranged from 14.6 to 86.1%.
pH of the fermented CJB ranged from...
Ferrites have been used for various high frequency applications as bulk
materials. These applications, however, are limited to large dimension devices. In
this thesis, thin film ferrites were deposited from a low temperature solution-based
deposition process that is suitable for micro-scale high frequency applications. The
low temperature nature of this...
Covalent organic frameworks (COFs) are an emerging type of microporous crystalline polymers connected by organic units via strong covalent bonds. Due to the well-defined crystalline structure and excellent chemical and thermal stabilities, COF materials are being considered as promising candidates in a variety of applications, such as gas adsorption, catalysis...
The need for less toxic quantum dots (QDs) has led to a significant number of investigations related to copper indium sulfide (CIS) QDs. Lower toxicity and broad band absorbance width makes CIS QDs appealing for light emitting diodes (LEDs), lasers, sensors, bio-imaging, solar cells, and computing. The optical and electronic...
Due to their viscoelastic properties, polymers and hydrogels are widely used in many applications. In this study, the viscoelastic properties of elastomer polymers were investigated for a series of hydrogel, hydrogel composites and silicon materials. A primary application for hydrogels and hydrogel composites is as a replacement for the degenerated...
Wireless High Definition Video Transmission (WHDVT) over 802.11-based networks enjoys widespread deployment among today's multimedia solutions. Examples include Intel® Wireless Display and Apple Airplay®, to name a few. In these systems, peer-to-peer networks are established over which H.264-encoded video is transported wirelessly to be decoded and played back at the...
Spray drying has been widely used in food science for long-term storage of products such as powdered milk, and it has recently been used for preservation of more temperature sensitive products such as human blood plasma and single-cell organisms. However, there are no previous reports of successful spray drying of...
General purpose computer systems have seen increased performance potential through the parallel processing capabilities of multicore processors. Yet this potential performance can only be attained through parallel applications, thus forcing software developers to rethink how everyday applications are designed. The most readily form of Thread Level Parallelism (TLP) within any...
The primary purpose of this study was to try to (1) provide information on the chemical nature, including turbidity formation, of polygalacturonic acid in different concentrations of NaCl solution. (2) use turbidity formation characteristics to develop an assay for determining the activities polygalacturonic acid depolymerases by using a polyelectrolyte. (3)...
The research presented in this dissertation focuses on the model generation and modeling processes of student teams that participate in capstone, undergraduate engineering physical and virtual laboratory projects. The Heat Exchange Laboratory Project, the Ion Exchange Laboratory Project, and the Virtual Chemical Vapor Deposition (CVD) Laboratory Project provide the context...
A digital phase locked loop (DPLL) and a statistical time-to-digital converter (STDC) were previously fabricated in a 0.35µm, 3.3V SOI CMOS process. This work summarizes these designs and characterizes the measured performance. Simulations supplement the measurements where applicable.
The DPLL was found to reach a locked state under a limited...
The brain has long attracted the interest of researchers. Some tasks, such as pattern
recognition and optimization, have proven to be exceptionally difficult for conventional
computing systems to perform, but are executed by the brain almost effortlessly. Due to
the large number of neurons and interconnections, it has proven impossible...
This thesis examines substrate noise coupling for NMOS transistors in heavily doped substrates. The study begins with the analysis of an NMOS transistor switching noise in a digital inverter at the device level. A resistive substrate network for the NMOS transistor is proposed and verified. Coupling between N+- P+ contacts...
The design of two 2.4GHz CMOS LC balanced oscillators in the 0.25μm National BiCMOS process for Bluetooth specifications is presented. These oscillators achieve low phase noise with low power consumption. At a frequency offset of 500KHz from the 2.11GHz carrier, the measured phase noise is -101.9dBc/Hz for the NMOS oscillator...
Retention of engineering students is a problem for many universities, especially during the first year. The problem of introducing students to engineering while increasing retention rates has recently been addressed by many different universities. Implementing novel lab structures, adjusting the lecture to incorporate more effective teaching techniques, and using orientation...
Digital inkjet printing is developing quickly today because inkjet printing processes consume less energy and water and produce less waste discharge than traditional dyeing and other printing technologies. Inkjet printing provides more versatility and flexibility in terms of printing patterns and colors. Natural pigments are gaining more attention today as...
Polyethylene terephthalate (PET) polymer has been the material of choice for packaging industry as a result of its excellent mechanical and physical properties. These properties are highly dependent on the microstructure, chemistry, and processing conditions of this material. PET is often oriented in the machine direction (MD), the transverse direction...
Boiling heat transfer is studied for its ability to dissipate high fluxes and achieve heat transfer coefficients two orders of magnitude greater than single-phase heat transfer systems. Heater surface enhancement with increased surface area, varied geometry, wettability contrast and micro/nano-structures can further enhance boiling heat transfer performance through bubble nucleation...
Resistance to moisture uptake is an important attribute of some wood preservatives and can help reduce moisture cycling that leads to the development of deep checks. While the potential for preservative treatments to help improve wood/moisture interactions is acknowledged, there are no tests that specifically evaluate this performance parameter. Checking...
A new technique is developed to recover elemental tellurium (Te) from cadmium telluride (CdTe) which is abundantly available in photovoltaic semiconductor waste. The method is based on microchannel fluid flow with the use of a supported liquid membrane (SLM) between the donor (feed) and acceptor (strip) channels. A predictive theoretical...
The benefits of physical activity (PA) are well established (USDDHS, 2008). Concern over the high rate of childhood obesity, however, has highlighted the emphasis of PA. Yet, children and adolescents are not obtaining the recommended amount of PA (CDC, 2011). Physical education (PE) has been recognized as an important source...
Efficient usage of resin is of critical importance to industry in the manufacture of wood composite panels, because resin represents a significant proportion of product costs. However, resin efficiency is poorly defined in literature, making it difficult to compare manufacturing processes in quantifiable terms. Additionally, resin content in the product...
Meeting the energy demands of the future is one of the most important challenges facing the engineering community today. An example of this problem is transportation fuels. Most of the current transportation fuels are composed of petroleum hydrocarbons. Finding a viable alternative is important given the potential scarcity of these...
Most general purpose protocols are found to suffer from
inefficiency in an Ethernet LAN environment when used for large
volume data transfer. This is especially true with the TCP/IP family
which was designed for a wide area network. This research work
presents a proof of this inefficiency and proposes a...
The low physical activity levels of children today are a cause for serious concern. When examining certain populations of children, such as children with Autism Spectrum Disorder (ASD), there is a possibility of even lower overall physical activity levels. However, when exploring the current literature examining the physical activity levels...
Steam distillation is the traditional method used for the extraction of peppermint oil. This process is able to remove approximately 20% of the oils from the leaves of the plant. It is a very costly and un-sustainable process due to the release of carbon emissions. Solvent free microwave extraction promises...
The hydrogen economy is a possible component of an energy future based on use of alternative and renewable energy sources, deemed desirable from the general consensus of the worldwide community that we do not want to further exacerbate the climate problems that we have introduced over the last two centuries...
Renewable energy is a topic of significant interest and importance in the world today. Ocean wave energy, particularly in areas such as the Oregon Coast, has considerable potential as a renewable resource. However, to rightly evaluate the overall cost of energy for wave energy converters, survivability and maintenance issues must...
Cellulose nanocrystals (CNCs) have received considerable attention over the last ten years because CNCs can be produced from renewable materials such as straw, wood, cotton, and sea animals (tunicates). CNCs are slender rods with high aspect ratios (10-100) and the final dimensions of the CNCs depend on the starting material....
Supercritical fluid (SCF) impregnation is a promising preservative treatment method, however, the development of SCF processes has been slowed by a limited understanding of the process. Developing a better understanding of the effects of various process parameters on treatment results would allow for a more rational development of SCF impregnation....
This work focusses on the modeling and the development of efficient coupled simulation techniques for MEMS based RF oscillators. High-level models for MEMS based varactors have been discussed and their accuracy issues are identified, based on comparisons with numerical simulations. A faster simulation approach based on the time-domain shooting method...
The purpose of this thesis is to explore methods which can reduce the power dissipation of a mobile system while decoding MPEG video. MPEG decoding is a microprocessor intensive process that makes heavy use of both the L1 and L2 caches as well as main memory. The heavy load placed...
Natural durability remains one of the most attractive characteristics of wood, and helps wood obtain a premium price. A worldwide shift towards the use of younger trees from intensively managed forests has created greater concerns about wood quality, especially the wood’s resistance to fungi and insects. Wood durability is assessed...
Background. Autism spectrum disorder (ASD) is characterized by impairments in social-communicative deficits and restricted and repetitive behaviors, interests, or activities (APA, 2013). While current estimates suggest 1 in 68 children are diagnosed with ASD, more alarming statistics indicate 1 in 50 school-aged children live with the disorder (Blumberg, Bramlett, Kogan,...
Atmospheric pressure plasma is non-thermal at millimeter to micrometer separations. It represents an alternative low exergy initiator of many chemical reactions. In many instances heat, light or sound are not efficient providers of the necessary energy to overcome chemical activation barriers. The focus of this research is applying dc nonthermal...
Marine biofouling is a major problem in many industries. Shipping has been afflicted with reduced vessel speed and hindered maneuverability due to organisms attaching since the dawn of sailing. To date, the primary method developed to prevent fouling is the application of biocide laden coatings with various release mechanisms. Mass...
Compact storage systems demonstrating increased hydrogen storage capacity are the key to advancing the growth of the hydrogen economy throughout the world and reducing the global dependence on fossil fuels for transportation. The use of highly porous adsorbent materials for reversible hydrogen storage is a promising pathway towards achieving storage...
The factors influencing the direct nitridation of silicon, including the effects of the native oxide layer covering the surface of silicon, the effects of hydrogen contained in the nitridation gas and the catalytic effects of metals added to the raw material silicon, were investigated, using a tubular flow reactor and...
Spiral inductors are a key component of mixed-signal and analog integrated circuits (IC's). Such circuits are often fabricated using silicon-based technology, owing to the inherent low-cost and high volume production aspects. However, semiconducting substrate materials such as silicon can have adverse effects on spiral inductor performance due to the lossy...
The feedbacks between hydrology and biogeochemical cycling of nitrogen (N) are of critical importance to global bioavailable N budgets. Human activities are dramatically increasing the amount of bioavailable N in the biosphere, which is causing increasingly frequent and severe impacts on ecosystems and human welfare. Streams are important features in...
Recent advances in nanocrystalline materials production are expected to impact the development of next generation low-cost and/or high efficiency solar cells. For example, semiconductor nanocrystal inks are used to lower the fabrication cost of the absorber layers of the solar cells. In addition, some quantum confined nanocrystals display electron-hole pair...
The variegated aqueous chemistries of metal cations are applied to the design and synthesis of non-toxic solution precursors suitable for additive printing of large-area oxide electronics. Polycondensation behaviors of aqueous Al+3 and PO4 +3 are manipulated in the deposition of atomically smooth amorphous aluminum oxide phosphate (AlPO) dielectric films. AlPO...
Digital-to-analog converters (DACs) with wide dynamic range and high
linearity are required for high-end audio applications. A multi-bit delta sigma
audio DAC, using a novel gain-correction technique, is described in this thesis. For
widely varying on-chip RC time constant, the DAC gain can be accurately
controlled by the correction circuitry....
In this piece of original work, I employ a Kunderian approach to fiction. The purpose of my novel is to examine how the causative element, a pivotal moment of change for a cast of characters, changes spatially and temporally. In Posthumously Yours, I explore themes of trauma, loss, and grief...
There is considerable interest in developing environmentally friendly processes for the economical conversion of biomass plant material to biofuels, bioproducts and biomaterials. One approach to such a conversion process is to make use of enzymes for the conversion of plant polysaccharides to simple sugars; the simple sugars could then be...
Two approaches to improving wood treatability include the modification of pressure
schedules during conventional liquid treatments and the use of supercritical fluids (SCFs). In
both of these techniques, pressure differences are important for transporting materials into
wood. The level of pressure and its change during SCF treatments are also important...
The lower Columbia River (LCR) riparian zone is rich in habitat diversity. However, the natural beauty and species diversity along the river have increasingly become affected by human activity. This study quantifies the areal extent and degree of wetlands change and associated causes along the LCR over the past 44...
The wetlands are distinguished from other lands of the Mid-Willamette Valley by excessive soil moisture. The wetlands, as defined for this study, consist of 20 soil series (in 22 soil mapping units) which are classified by the Soil Conservation Service as having excessive wetness as the major factor limiting their...