Hydrogen is the green fuel that can be produced from water through electrolysis and used via hydrogen fuel cells to generate electricity with zero carbon dioxide emission. The commercialization of electrolyzers and fuel cells is the critical step to achieving global carbon neutrality. However, it is severely hampered by the...
Water splitting is a green method being researched to produce green hydrogen in order to combat greenhouse gases emitted by the most popular energy source; fossil fuels. Water splitting involves two half reactions: hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Of these two, OER is the bottleneck water...
Previous observations and simulations suggest that an approximate 3°–5°C warming occurred at intermediate depths in the North Atlantic over several millennia during Heinrich stadial 1 (HS1), which induces warm salty water (WSW) lying beneath surface cold freshwater. This arrangement eventually generates ocean convective available potential energy (OCAPE), the maximum potential...
Oxides are a versatile class of materials with a wide range of electronic, optical, and magnetic properties. This makes them ideal for use in a multitude of functional devices for oxide electronics, electrochemical conversion, and storage. The overall performance of these devices is governed by atomic scale charge and mass...
In this dissertation, I describe the experimental investigation in electron diffraction of molecules in superfluid helium droplets. The project is part of an overall scheme called ‘single molecule serial electron diffraction imaging’ (SS-EDI), with the ultimate goal of building an apparatus to determine atomic structures from oriented macromolecules. In SS-EDI,...
Ultra high temperature (UHT) processing can extend shelf life of milk to several months without refrigeration, which is more convenient and energy saving than pasteurized milk. However, the poor acceptance caused by "cooked" flavors limits its marketing growth, especially in United States. Ohmic heating, which has a more uniform and...
RNAs play important roles in the central dogma of molecular biology, and are involved in multiple biology processes such as chromatin modification, transcriptional interference and translation initiation. The functions of RNAs, especially non-coding RNAs, are highly related to its secondary structures, therefore computational methods for RNA structure prediction are of...
Rising atmospheric [CO₂], cₐ, is expected to affect stomatal regulation of leaf gas-exchange of woody plants, thus influencing energy fluxes as well as carbon (C), water, and nutrient cycling of forests. Researchers have proposed various strategies for stomatal regulation of leaf gas-exchange that include maintaining a constant leaf internal [CO₂],...
The ongoing retreat of glaciers globally is one of the clearest manifestations of recent global warming associated with rising greenhouse gas concentrations. By comparison, the importance of greenhouse gases in driving glacier retreat during the most recent deglaciation, the last major interval of global warming, is unclear due to uncertainties...
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Shakun, J. D., Clark, P. U., He, F., Lifton, N. A., Liu, Z., & Otto-Bliesner, B. L.
(2015). Regional and
The ongoing retreat of glaciers globally is one of the clearest manifestations of recent global warming associated with rising greenhouse gas concentrations. By comparison, the importance of greenhouse gases in driving glacier retreat during the most recent deglaciation, the last major interval of global warming, is unclear due to uncertainties...
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rates for
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The ongoing retreat of glaciers globally is one of the clearest manifestations of recent global warming associated with rising greenhouse gas concentrations. By comparison, the importance of greenhouse gases in driving glacier retreat during the most recent deglaciation, the last major interval of global warming, is unclear due to uncertainties...
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Elevation Elv/pressure Thickness Density Shielding Erosion rate [He-3] +/- mineral Sample age error
During mitosis, sister chromatids are separated by the action of the mitotic spindle. The mitotic spindle attaches to chromosomes at centromeres through a protein complex called the kinetochore. While ~100 proteins have been identified at kinetochores and centromeres, the function of most is poorly understood.
The centromere protein, CENP-T (Centromere...
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Neurospora. crassa centromere
A role for CENP-S,T,W,X at Neurospora crassa centromeres?
Mu Feng
Mentor: Dr
Reliable controller designs have been developed in this thesis for a number of finite-horizon
and infinite-horizon problems with possibly non-zero initial conditions. These
reliable controllers assure that system stability and system performance will be
maintained despite certain system faults. The performance measure used in this thesis is
an "H[subscript ∞]-like...
This paper presents a model of the determination of excise tax rates by studying the
substantial variation in the state excise taxes in the U.S. brewing industry. Two
approaches are used. First, assuming that the government is only interested in the public
interest, a socially optimal tax rate is derived....
To explore the possible causes of abusive supervision and rudeness, I used an interactive approach to test whether one domain of implicit personality (implicit aggression) and self-control resource depletion are interactive predictors. By using a sample of 83 students in a large public university in the North Western United States,...
Object recognition is a fundamental problem in computer vision. Recognition is
required by many applications. This thesis presents a distance based approach to
recognize objects. We are interested in objects that belong to very similar classes,
where each class has large variations. This problem is called fine-grained object
recognition. Given...
The influence of alfalfa fiber level 28, 54 and 74% in diets on
the proximate compositions, pH and water-holding capacity of raw and
cooked rabbit meat were investigated.
Preslaughter live weight, percent dress weight and percent
abdominal fat of rabbits fed 54% alfalfa fiber diet were
significantly higher and total...
The continuum theory provides a framework in which the growth
of a plant root as a dynamic process involving interactions among
transport of water and solute, cell division, and the subsequent cell
elongation can be described. A plant root is modeled as a one-dimensional,
multi-phase, mathematical continuum. The network of...
This thesis consists of three papers which investigate marginal models, nonparametric approaches, generalized mixed effects models and variance components estimation in longitudinal data analysis. In the first paper, a new marginal approach is introduced for high-dimensional cell-cycle microarray data with no replicates. There are two kinds of correlation for cell-cycle...
The objectives of this study were to 1) measure and compare the compositional differences of essential oil among three hop cultivars ('Centennial’, 'Citra' and 'Nelson Sauvin'), 2) identify the odor-active aroma compounds in three varieties of hops and 3) investigate the behavior of hop-derived aroma compounds in beers prepared by...
This dissertation contains three essays on nonprametric and semiparametric regression mod-
In the first essay, we propose an estimation procedure for value at risk (VaR) and expected
shortfall (TailVaR.) for conditional distributions of a time series of returns on a financial asset.
Our approach combines a local polynomial estimator of...
High vegetative growth of Pinot Noir vine is a common problem in most vineyards of Oregon's Willamette Valley, where sunlight exposure and heat accumulation are limited. Consequently, growers in this region commonly use vineyard management strategies to regulate vine vigor and improve grape and wine quality. Wine quality is greatly...
Cell division, arguably the most important event during the life cycle of the eukaryotic cell, is achieved through a complicated yet beautiful machinery. The mitotic spindle — a microtubule-based bipolar structure—is the cellular machinery responsible for the correct segregation of the genetic material, chromosomes. The protein-based nanomachines termed molecular motors...
By using immobilized trypsin, I have been able to
prepare well-defined, stable trypsinized nucleosomes. The
difficulties of lacking of control in the extent of
trypsinization, which were encountered in previous studies
with the use of free trypsin, have been eliminated. The
nucleosomes and oligonucleosomes prepared by immobilized
trypsin are suitable...
In this study, I investigate how target value uncertainty may lead to acquirer mispricing of an acquisition target and how the mispricing may be a determinant of goodwill impairment. To the extent the mispricing leads to both high and low industry-adjusted purchase price multiples (PPMs are my proxies for overpayment...
The advancement of artificial intelligence (AI) has led to transformative developments across multiple sectors, fostering innovation and redefining our interactions with technology. As AI matures and becomes integrated into society, it offers numerous opportunities to address global challenges and revolutionize a wide array of human endeavors. These advances are driven...
Metallic glasses are attracting tremendous attention because of their fundamental significance and great potential to be used as structural or functional materials in engineering applications. Significant efforts have been devoted to studying their unique properties as well as their disordered nature. Metallic glasses possess much higher strength and elastic strain...
The ongoing retreat of glaciers globally is one of the clearest manifestations of recent global warming associated with rising greenhouse gas concentrations. By comparison, the importance of greenhouse gases in driving glacier retreat during the most recent deglaciation, the last major interval of global warming, is unclear due to uncertainties...
We report electron diffraction of ferrocene doped in superfluid helium droplets. By taking advantage of the velocity slip in our pulsed droplet beam using a pulsed electron gun, and by doping with a high concentration of ferrocene delivered via a pulsed valve, we can obtain high quality diffraction images from...
Bimetallic catalysis is a promising way to tune the catalytic properties of heterogeneous catalysts. In particular, bimetallic catalysts are extensively used to enhance the selectivity of monometallic catalysts in a variety of contexts, from oxidation catalysis to oxygenate coupling. In this work, we investigate PdxCuy/SiO2 and PdxAgy/SiO2 catalysts in the...
Mg-MOF-74 is one type of metal-organic frameworks (MOFs) that is widely known for its excellent CO2 uptake capacity. More intriguingly, it can be used to detect low levels of toxic gas such as CO2. Currently, most research into Mg-MOF-74 focuses on using the powder type as a CO2 absorbent because...
The continuous development of higher performing battery materials has emerged in parallel with the development of new manufacturing processes. Nanomaterials are one solution to addressing the cycling and performance challenges that limit existing battery cells. However, many of the methods used today for nanomaterial synthesis are high temperature batch methods...
Copper zinc tin sulfide (CZTS) is a potential solar material for thin film solar cells according to its suitable band gap in the visible light range, high absorption coefficient, low toxicity, good photostability and relative earth abundance of component elements. However, the production cost of this solar thin film material...
Modification of microbial electrolysis cells (MECs) by altering the sizes of the anode and the cathode, or their interaction with the liquid stream affects the performance of the MEC, but it remains difficult to quantify how much each change will contribute to the overall performance. Through this study, a method...
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...
Heterogeneous catalysis modulates the rate and selectivity of reaction processes by
stabilizing a series of intermediate states on solid surfaces, facilitating the production
of many commodity chemicals modern society relies upon. Conventional, thermal
catalytic processes—conducted at elevated temperatures and pressures—source
thermal, mechanical, and chemical potential energy from carbon-hydrogen bonds—
combustion...
It is desirable for complex engineered systems to perform missions efficiently and economically, even when these missions' complex, variable, long-term operational profiles make it likely for hazards to arise. It is thus important to design these systems to be resilient so that they will actively prevent and recover from hazards...
Greenland ice core water isotopic composition (δ¹⁸O) provides detailed evidence for abrupt climate changes, but is by itself insufficient for quantitative reconstruction of past temperatures and their spatial patterns. We investigate Greenland temperature evolution during the last deglaciation using independent reconstructions from three ice cores and simulations with a coupled...
Resistance against Bean common mosaic virus (BCMV) in Phaseolus vulgaris is governed by six recessive resistance alleles at four loci. One of these alleles, bc-3, is able to protect P. vulgaris against all BCMV strains and against other potyviruses; bc-3 was identified as the eIF4E allele carrying mutated eukaryotic translation...
The demand for the development of sustainable energy is an all time high as we burn through limited fossil fuel reserves and as environmental concerns rise every year. Renewable energy sources such as wind and solar power have limitations due to inconsistent power supply that cannot meet the regular needs...
Metallic glasses (MGs) have attracted tremendous attention because of their unique properties and potential applications in the future industry. However, it is still a mystery for people to understand the formation mechanism of the bulk MGs (BMGs). To produce BMGs, the specific composition of materials, sufficiently high cooling rate, etc.,...
The development of nanomaterials and the potential enhancement of their chemical, mechanical, electrical, and optical properties have led to the investigation of methods for their synthesis at lower cost with enhanced performance for next generation devices. Along with the pursuit of new materials that exhibit properties of interest, industry requires...
Widespread installation of renewable energy sources, such as wind and solar, has been delayed by the lack of suitable stationary energy storage solutions. Current large-scale technologies, such as pumped hydro and compressed air, are geographically restricted. This is where electrochemical energy storage - batteries or hybrid capacitors can play a...
There is an emerging interest in developing wearable electronics as a platform, which
provides the flexibility of a wearable while maintaining its promising functionality as smart textiles. Metal-halide semiconductors are attractive materials with tunable optical and electrical properties. Researchers have widely studied and applied it for advanced
photonics and optoelectronic...
The grand plan of carbon neutralization and COP26 in Glasgow require a quick shift of energy sources from conventional fossil fuel to a more renewable substitute such as wind, or solar energy. However, the intermittency of those renewable energy sources does not meet the demand of the energy, which requires...
Surface characterization of materials is widely utilized over a range of disciplines and essential to the development of new materials, technology, or processes. Metal oxide nanoclusters have shown promise as potential new generation photoresist materials for extreme ultraviolet (EUV) nanolithography. Organotin clusters have been proposed as potential candidates for resist...
Grid-scale energy storage systems are urgently needed to increase the flexibility and rigidity of the grid for modern society and take full advantage of the renewable green energy resources such as solar energy and wind energy. Na-ion batteries (NIBs) and K-ion batteries (KIBs) have been emerged as one of the...
Water electrolysis plays a pivotal role in achieving a green hydrogen economy by sourcing electricity from intermittent renewable sources. However, the efficiency of the electrolysis process is limited by the sluggish oxygen evolution reaction (OER) kinetics, whereas the kinetics of the hydrogen evolution reaction (HER) are more facile. This thesis...
This thesis concerns the development of a direct torque control strategy using a sliding mode control approach to optimize the power output of an oscillating water column (OWC) wave energy converter (WEC). The OWC WEC is a device that has a submerged vertical tail tube open at both ends, which...