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Effects Of Baffles On Damping Lateral Fluid Sloshing Oscillations In Tanker Trucks, Rohit Kumar Tanugula Dec 2001

Effects Of Baffles On Damping Lateral Fluid Sloshing Oscillations In Tanker Trucks, Rohit Kumar Tanugula

Graduate Theses, Dissertations, and Problem Reports (ETD)

Partially filled heavy-duty tanker trucks maneuvering constant radius turns or lane change maneuvers have lower rollover threshold than other vehicles because of the high center of gravity and dynamic sloshing of the liquid payload. Payloads are often toxic and hence, rollover accidents can be catastrophic. Therefore, attempts to increase the threshold velocity and predicting its value under various on-road maneuvers are of paramount importance.;This research was aimed at studying the effects of baffles on reducing the lateral sloshing and thereby, improving the stability of heavy-duty trucks. Various configurations (horizontal, vertical, horizontal and vertical, and diagonal) of baffles were considered for …

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Factors Affecting The Accumulation Of Pentosidine In The Skin Of Wild Birds, Richard Clair Chaney Jr. Dec 2001

Factors Affecting The Accumulation Of Pentosidine In The Skin Of Wild Birds, Richard Clair Chaney Jr.

Graduate Theses, Dissertations, and Problem Reports (ETD)

Birds have few reliable indicators of aging. Pentosidine (Ps), a biomarker of aging, is a product of non-enzymatic glycation, which accumulates in the tissues of an animal over its lifespan. The intent of this study was to determine if comparable change in Ps concentrations could be established in the skin of wild birds of known ages. Skin samples were obtained from the breast of 44 birds of various species. Foot webbing samples were obtained from 24 California Gulls. Collagen was measured by a hydroxyproline spectrophotometric method and Ps was quantified using reverse phase HPLC. Ps concentration in the skin and …

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Habitat Utilization And Movement Patterns Of Subadult Largemouth Bass (Micropterus Salmoides) In The Ohio River, Elizabeth Marie Hoffman Dec 2001

Habitat Utilization And Movement Patterns Of Subadult Largemouth Bass (Micropterus Salmoides) In The Ohio River, Elizabeth Marie Hoffman

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ohio River electrofishing surveys identified embayments as preferred macrohabitat of subadult largemouth bass. Catch rates within macrohabitats were low ranging from 0.00--2.73 subadult bass/hour. Embayment electrofishing CPUE was higher than tributary or main channel except in spring, when tributary CPUE was highest.;Core use areas were calculated from biotelemetry data and ranged from 88--59,400 m2, representing 0.02--89.00% of available study location macrohabitat. Subadult bass movement was limited to nursery embayments or tributaries with infrequent movement to nearby main channel areas. Bass preferred a mixed microhabitat consisting of a combination of vegetation and woody debris. This mixed microhabitat was less common in …

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Influence Of The West Virginia Dome On Paleocurrent Patterns In The Upper Devonian-Lower Mississippian Price Formation In The Central Appalachians, Sheldon James Murphy Dec 2001

Influence Of The West Virginia Dome On Paleocurrent Patterns In The Upper Devonian-Lower Mississippian Price Formation In The Central Appalachians, Sheldon James Murphy

Graduate Theses, Dissertations, and Problem Reports (ETD)

Upper Devonian-Lower Mississippian sedimentation was influenced by a positive area known as the West Virginia Dome located in the Central Appalachians of West Virginia. Paleocurrent data collected from the Price Formation demonstrates the significance of the dome on paleoflow patterns. Exposures in West Virginia are located along the Allegheny Front and include the lowermost marine Oswayo Member, Riddlesburg Shale Member, unnamed Upper Member and the uppermost non-marine Rockwell Member. These units overlie the Devonian Hampshire Formation or Greenland Gap Formation and underlie the Mississippian Greenbrier Limestone or Maccrady Formation. At the center of the dome the Price Formation is absent …

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Changes In Water Quality In Deckers Creek From 1974 To 2000, Jason Allen Stewart Dec 2001

Changes In Water Quality In Deckers Creek From 1974 To 2000, Jason Allen Stewart

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Deckers Creek drainage basin covers approximately 16,600 hectares (62.9 square miles) in Monongalia and Preston Counties of West Virginia. Throughout the twentieth century, this watershed has received high levels of pollution in several forms. A 1974 study examined the water chemistry in Deckers Creek over a six-month period at 29 sample points. Water samples from the same sites were collected and analyzed monthly from March 1999 through October 2000 for acidity, alkalinity, total iron, aluminum, manganese, and other metals, as well as for fecal coliform and fecal streptococcus concentrations. Most of the tributaries sampled in 1999--2000 showed reduced metal …

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Characterization And Quality Of Soils Developing On A Mountaintop Removal Coal Mine, Kevin Alfred Thomas Dec 2001

Characterization And Quality Of Soils Developing On A Mountaintop Removal Coal Mine, Kevin Alfred Thomas

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mountaintop surface mining for coal has been practiced in West Virginia for over three decades, but its environmental impacts have become increasingly scrutinized in recent years. Therefore, this study evaluated soil development on different aged mined lands. Four different ages (2, 7, 11, and 23 years) of minesoils and two different slope classes, nearly level to gently sloping and steep to very steep, along with three contiguous native soils on a reclaimed mountaintop removal mine in Logan County, West Virginia were described and sampled. Standard analyses of physical and chemical properties were conducted in order to classify these soils. Some …

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Major Problems Associated With The West Virginia Forest Sector As Perceived By West Virginia Division Of Forestry Service Foresters, Michael Allen Westfall Ii Dec 2001

Major Problems Associated With The West Virginia Forest Sector As Perceived By West Virginia Division Of Forestry Service Foresters, Michael Allen Westfall Ii

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study was designed to identify problems facing the forest sector in West Virginia as perceived by West Virginia Division of Forestry Service Foresters.;The descriptive method of research using questionnaire techniques was utilized in the study. Data were obtained from 48 service foresters (73% response).;Overall means were determined for each statement. The population was assumed a sample of service foresters at a point in time, thus the use of inferential statistics. Statistical procedure used for analyzing the data was analysis of variance statistical tests.;The results show that 4 of the 48 problem statements were rated as severe problems with a …

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Pest Management Practices Used By West Virginia Corn Growers, Leasa Dianne Wilkerson Dec 2001

Pest Management Practices Used By West Virginia Corn Growers, Leasa Dianne Wilkerson

Graduate Theses, Dissertations, and Problem Reports (ETD)

The purpose of this study was to provide information that might be useful to researchers and extension personnel at West Virginia University in developing and designing educational programs concerning pest management for corn farmers. This research identified current trends in management practices, insect, fungal, and weed problems, and educational needs so that instructional materials can be designed to meet clientele needs. Data were collected via 100 questionnaires mailed to farmers in the top ten corn producing counties in West Virginia. Of these, thirty-three useable surveys were returned.;It was found that Gray leaf spot and Maize virus were the most prevalent …

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Raptor Abundance And Diversity And Red-Shouldered Hawk ( Buteo Lineatus) Habitat Characteristics On Reclaimed Mountaintop Mines In Southern West Virginia, Melissa J. Balcerzak Dec 2001

Raptor Abundance And Diversity And Red-Shouldered Hawk ( Buteo Lineatus) Habitat Characteristics On Reclaimed Mountaintop Mines In Southern West Virginia, Melissa J. Balcerzak

Graduate Theses, Dissertations, and Problem Reports (ETD)

Raptor abundance and diversity were compared between 4 treatments (grassland, shrub/pole, fragmented forest, and intact forest) over 3 seasons (migration, summer, and winter) on 3 mountaintop/valley fill mines in southern West Virginia. Habitat characteristics of Red-shouldered Hawks (Buteo lineatus) were examined at landscape and microhabitat scales. Forty-eight points were surveyed monthly (Feb. 2000--Jan. 2001) using broadcast calls. I quantified microhabitat characteristics within an 11.3 m radius plot and landscape characteristics within 1000 and 564 m buffer zones at each point. Abundance was highest in grasslands; richness did not differ among treatments. Overall, I detected a shift from a forest to …

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Robust Decentralized Control Of Power Systems Through Excitation Systems And Thyristor Controlled Series Capacitors, Lingling Fan Dec 2001

Robust Decentralized Control Of Power Systems Through Excitation Systems And Thyristor Controlled Series Capacitors, Lingling Fan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this work is robust decentralized control of power systems through excitation systems and Thyristor Controlled Series Capacitors (TCSC). Hence the dissertation consists of two parts. In the first part an algorithm for the design of nonlinear decentralized excitation control is developed based on a feedback linearization technique. Feedback linearization technique is applied in excitation control of each generator to obtain an interconnected system where subsystems have linear system matrices and interconnections are represented by nonlinear terms. Different ways of achieving decentralization are investigated: (1) linear robust control combined with observer decoupled state space; (2) disturbance accommodation control. …

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Prenatal Stress Alters Fear-Conditioned Behaviors And The Response To Serotonergic Drugs, William C. Griffin Iii Dec 2001

Prenatal Stress Alters Fear-Conditioned Behaviors And The Response To Serotonergic Drugs, William C. Griffin Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

Chronic, inescapable stress during pregnancy (i.e. prenatal stress) modifies the behavior of the adult offspring. Several behaviors were evaluated in adult prenatally stressed (PS) rats, most notably the acoustic startle response and behavioral inhibition (i.e. freezing). PS rats do not differ in baseline peak startle responding, or in the habituation of the peak startle response when compared to the non-prenatally stressed (CON) rats. However, PS rats have greater peak responses and longer latencies to reach the peak response following systemic doses of the 5-HT 1A agonist, 8-OH-DPAT, compared to CON rats. The PS rats had shorter latencies than the CON …

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Psychometric Properties Of The Social Interactions Questionnaire (Siq) In An Older Adult Sample, Kimberly Debra Kalish Dec 2001

Psychometric Properties Of The Social Interactions Questionnaire (Siq) In An Older Adult Sample, Kimberly Debra Kalish

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined the psychometric properties of the Social Interactions Questionnaire (SIQ; Kalish & Edelstein, 1996), a quick and efficient tool to measure negative social interactions. Overwhelming evidence has emerged over the past decade indicating that negative social interactions (NSIs) are strongly related to measures of mental and physical health. A critique of existing measures of NSIs reveals long and cumbersome interviews that are comprised of some, but not all, of the critical elements of NSIs. The SIQ efficiently measures these critical elements, which include (a) perceived versus structural components of NSIs, (b) seven different types of NSIs, (c) overall …

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Pharmacological Regulation Of C-Myc Gene Expression In Human Breast Cancer Cells, Zaroui Karlen Melkoumian Dec 2001

Pharmacological Regulation Of C-Myc Gene Expression In Human Breast Cancer Cells, Zaroui Karlen Melkoumian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Previous studies demonstrated that quinidine causes G1/G0 cell cycle arrest and inhibition of proliferation in MCF-7 human breast cancer cell line (Woodfork, K. et al., 1995). The goal of studies reported here was to understand the molecular mechanisms of c-myc gene regulation by quinidine. C-myc is one of the most common oncogene aberrations in breast cancers (Deming, S. L. et al., 2000). C-myc functions include regulation of cell cycle, proliferation, differentiation, and apoptosis. The results of these studies demonstrated that quinidine causes rapid (within 1 hour) suppression of Myc protein and mRNA levels that precedes the quinidine-induced G1 cell cycle …

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Women And Physical Culture In Modern Poland, Nameeta Mathur Dec 2001

Women And Physical Culture In Modern Poland, Nameeta Mathur

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation examines the interaction between the various forces of Polish "nationalism" and "feminism" in the construction of women's physical culture in modern Poland from the late nineteenth century until the end of the twentieth century. The basic premise of this work is that unlike most western countries where sportswomen have typically been marginalized in their athletic endeavors, Polish female athletes have earned far greater respect and recognition in the development of their physical culture. On many occasions, women's athleticism in Poland was a source of immense pride and prestige for both the state and society, albeit for varied reasons …

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Large -Eddy Simulation Of A Three-Dimensional Compressible Tornado Vortex, Jianjun Xia Dec 2001

Large -Eddy Simulation Of A Three-Dimensional Compressible Tornado Vortex, Jianjun Xia

Graduate Theses, Dissertations, and Problem Reports (ETD)

Large-Eddy simulation (LES) has become a very useful tool for investigating tornadoes, one of the more spectacular and destructive phenomena of nature. A new three-dimensional, unsteady, compressible model is generated to determine how significant the differences between compressible and incompressible LES simulations may be in some extremely violent tornadoes. In particular, this study seeks to determine how high the Mach number within the tornado may become before significant changes occur due to compressibility, and what the major effects of these changes may be expected to be.;After developing and verifying the compressible LES model, three different patterns of tornadic corner flows …

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Transfer Of Heart Rate Feedback Training To Reduce Heart Rate Response To Laboratory Tasks, Jeffrey Louis Goodie Dec 2001

Transfer Of Heart Rate Feedback Training To Reduce Heart Rate Response To Laboratory Tasks, Jeffrey Louis Goodie

Graduate Theses, Dissertations, and Problem Reports (ETD)

Researchers have demonstrated that individuals can successfully reduce their heart rate (HR) response to a stressor when provided with heart rate feedback. However, it is unclear whether individuals can transfer HR reduction skills to stressors not used during HR feedback training. The present study used a multiple baseline, single subject design to examine the transfer of HR feedback training among six individuals. Participants were provided with HR feedback training during the presentation of a videogame, a mental arithmetic challenge, and a hand grip task until the participants reduced their HR to within 4 bpm of their resting HR or until …

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Electrochemical Fabrication Of Semiconductor Nanostructure Arrays For Photonic Applications, Stephen Patrick Mcginnis Dec 2001

Electrochemical Fabrication Of Semiconductor Nanostructure Arrays For Photonic Applications, Stephen Patrick Mcginnis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Theoretical and experimental investigations of the properties of semiconductor nanostructures have been an active area of research due to the enhanced performance that is observed when electrons and holes are spatially confined in one, two or three dimensions. However, the development of viable photonic devices using this phenomenon requires the development of appropriate fabrication techniques that can provide control over nanostructure size, material composition, and periodicity for structures with dimensions less than 20 nm. To address these challenges, a nanostructure synthesis technique has been developed that is based on the self-organization of nanometer scale pores during the anodization of aluminum …

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Parent-Infant Interactions During Acute Painful Procedures, Catherine Bradford Mcclellan Dec 2001

Parent-Infant Interactions During Acute Painful Procedures, Catherine Bradford Mcclellan

Graduate Theses, Dissertations, and Problem Reports (ETD)

Despite the current recognition of infant procedural pain and distress, there is a dearth of research, both in the assessment and treatment literature, of infant procedural distress. This study examined how specific parent behaviors relate to infant procedural distress and whether this relation is mediated by birth order. Results indicated that females were rated as more distressed than were males, and that birth order did not prove to be a distinguishing factor in infant distress. Finally, while some behaviors appear to have a similar influence on both preschoolers' and infants' behaviors, parents' behavior during infants' distressing procedures were found to …

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Potential Relations Between Extraversion And Cardiovascular Reactivity During Laboratory Stressors, Brandie K. Taylor Dec 2001

Potential Relations Between Extraversion And Cardiovascular Reactivity During Laboratory Stressors, Brandie K. Taylor

Graduate Theses, Dissertations, and Problem Reports (ETD)

This present study was designed to examine the relation between cardiovascular reactivity to stress and the behaviors of individuals classified as either "extraverts" or "introverts." Although experimental psychophysiological studies have been conducted to examine the relation between extraversion and physiological arousal, little is known about the ways in which extraversion and cardiovascular reactivity to stress are related. According to the optimal arousal theory, both extraverts and introverts would be expected to be more reactive to a social challenge than to a mundane non-social task, with introverts exhibiting greater reactivity to both tasks than extraverts. In contrast, a preferred task model …

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Reasons For Living Across The Lifespan, Lesley P. Koven Dec 2001

Reasons For Living Across The Lifespan, Lesley P. Koven

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study examined gender and age-related differences in reasons for living, using a sample of 50 young adults (M = 20.2), 53 middle-aged adults (M = 49.3), and 55 older adults ( M = 78.5). Participants completed a combined version of the Reasons for Living Inventory, the Reasons for Living Inventory for Younger Adults, and the Reasons for Living Inventory for Older Adults. Although no gender differences emerged in reasons for living, younger adults placed more importance on fear of social disapproval, moral objections, survival and coping skills, peer acceptance, survival and coping beliefs, fear of suicide, and future optimism …

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Analytical And Experimental Study Of Frp Honeycomb Sandwich Panels With Sinusoidal Core, Justin Mark Robinson Aug 2001

Analytical And Experimental Study Of Frp Honeycomb Sandwich Panels With Sinusoidal Core, Justin Mark Robinson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber reinforced plastic (FRP) composite materials and structures have been increasingly used in highway bridge applications. Recent applications have demonstrated that FRP honeycomb sandwich panels with sinusoidal core can be effectively and economically used for highway bridge deck systems. In this study, analytical and experimental characterizations are presented for a FRP honeycomb panel with sinusoidal core geometry in the plane and extending vertically between face laminates. To verify the accuracy of the a closed-form solution, several honeycomb sandwich beams with sinusoidal core waves either in the longitudinal or transverse directions are tested in bending and torsion. Also, a deck panel …

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Curriculum Alternatives In Graduate Dental Hygiene Education, Jennifer Hubbard Grilli Aug 2001

Curriculum Alternatives In Graduate Dental Hygiene Education, Jennifer Hubbard Grilli

Graduate Theses, Dissertations, and Problem Reports (ETD)

The nursing profession has designed a variety of curriculum options for individuals who wish to pursue graduate education in nursing. These options have been created to meet the changing needs of their profession, society, and potential students in the field. The profession of dental hygiene has similar needs. Presently there are only nine programs granting graduate degrees in dental hygiene. More graduate programs are needed to fulfill the future demands for educators, researchers, and practitioners with the knowledge and skills necessary to provide advanced levels of care in a variety of practice settings. Unfortunately, a mean of only 20 students …

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Green-Ampt Infiltration Model Parameter Determination Using Scs Curve Number (Cn) And Soil Texture Class, And Application To The Scs Runoff Model, Elena Viktorovna Brevnova Aug 2001

Green-Ampt Infiltration Model Parameter Determination Using Scs Curve Number (Cn) And Soil Texture Class, And Application To The Scs Runoff Model, Elena Viktorovna Brevnova

Graduate Theses, Dissertations, and Problem Reports (ETD)

The U.S. Department of Agriculture (USDA) Soil Conservation Service Curve Number (SCS CN) method is a simple and widely popular technique of estimation of direct runoff volume for design and natural rainfall events in small watersheds. The SCS CN procedure is incorporated into such computer programs as TR-20 and TR-55. Although the method reliably predicts 24-hr runoff volume, the predicted distribution of runoff during a storm event is not realistic. This shortcoming of the SCS CN method is due to weakness in the infiltration concept of the method. Use of a physically realistic and distributed Green-Ampt infiltration model can significantly …

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Simulation Based Modeling Of The Elastic Properties Of Structural Wood Based Composite Lumber, Laszlo Bejo Aug 2001

Simulation Based Modeling Of The Elastic Properties Of Structural Wood Based Composite Lumber, Laszlo Bejo

Graduate Theses, Dissertations, and Problem Reports (ETD)

The importance of wood-based composite lumber is increasing in the US market for construction materials. Manufacturers of such composites strive to make their products more competitive by increasing their value. This dissertation describes the development of simulation models that can aid these efforts by estimating the elastic characteristics of composite lumber products. The study included the assessment of the orthotropic mechanical properties of the raw material, the effect of densification it experiences during the hot-pressing procedure, and the geometric structure of the composites. Using the results of these investigations, computer models were created based on principles of deterministic and stochastic …

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Nondestructive Testing Of Reinforced And Prestressed Concrete Structures Using Acoustic Waveguides, Komwut Wissawapaisal Aug 2001

Nondestructive Testing Of Reinforced And Prestressed Concrete Structures Using Acoustic Waveguides, Komwut Wissawapaisal

Graduate Theses, Dissertations, and Problem Reports (ETD)

The main objective of this research is to develop both passive and active nondestructive testing techniques for reinforced and prestressed concrete structures using acoustic waveguides. The first technique introduces a two-dimensional surface waveguide to enlarge the acoustic emission (AE) monitoring area of a reinforced concrete structure. A two-dimensional steel wire system is developed as an acoustic waveguide to study the AE behavior of a reinforced concrete floor slab. AE sensors are mounted to the end of the waveguides to detect AE signals, which are generated by pencil-lead breaks at various locations on concrete surface. Results show that the use of …

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Higher Order Chromatin Degradation Induced By Hydrogen Peroxide In Glial Cells, Raymond Mouzannar Aug 2001

Higher Order Chromatin Degradation Induced By Hydrogen Peroxide In Glial Cells, Raymond Mouzannar

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study addresses the genotoxicity of oxidative stress. We induced oxidative stress in cultured rat oligodendrocytes by exposure to hydrogen peroxide (H2O2). Intact genomic DNA was isolated by agarose embedding and its fragmentation was assessed by field inversion gel electrophoresis (FIGE). To detect single strand fragmentations, the DNA was digested with S1 nuclease before FIGE. We found that the exposure of oligodendrocytes to pathological concentrations of H2O2, induces a rapid digestion of nuclear chromatin in a pattern consistent with higher order chromatin degradation (HOCD). HOCD, the hallmark of programmed cell death (PCD), proceeds through single strand scissions that accumulate at …

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Physiological Study Of Cold Acclimation In Rhododendron Sp. With Emphasis On Role Of Dehydrins, Calin O. Marian Aug 2001

Physiological Study Of Cold Acclimation In Rhododendron Sp. With Emphasis On Role Of Dehydrins, Calin O. Marian

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study we established the significance of 25 kDa dehydrin accumulation during cold acclimation (CA) in a wide array of Rhododendron species. These species (24 in total) belong to two diverse subgenera, Hymenanthes and Rhododendron, native to diverse latitudes and altitudes. The dehydrin of interest is highly conserved in Rhododendron genus and was present and up-regulated during CA in all the species studied with one exception---R. brookeanum ---a species adapted to tropics. Some other dehydrins were also found to accumulate in response to cold acclimation in several species, but none of these accumulated consistently. Experimental data show that there …

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Synthesis Of Derivatives Of 4h-Cyclopenta[ Def]Phenanthren-4-One And Development Of Synthetic Strategies For The Polycyclic Aromatic Hydrocarbons With Carbon Frameworks Represented On The Surface Of C60, Xiaoqing Han Aug 2001

Synthesis Of Derivatives Of 4h-Cyclopenta[ Def]Phenanthren-4-One And Development Of Synthetic Strategies For The Polycyclic Aromatic Hydrocarbons With Carbon Frameworks Represented On The Surface Of C60, Xiaoqing Han

Graduate Theses, Dissertations, and Problem Reports (ETD)

A derivative of 4H-cyclopenta[def]phenanthren-4-one, 51, was synthesized from the protected ninhydrin 54 and 2 equivalents of 1-(2-ethynylphenyl)-2-phenylethyne. Condensation of the diketone 54 with the lithium acetylide 55 furnished the trans propargylic alcohol 56a and the cis propargylic alcohol 56b. Treatment of 56a with thionyl chloride promoted a sequence of reactions presumably with an initial formation of the chlorinated benzoenyne-allene 58. Two cycles of a C2--C6 biradical cyclization reaction followed by a radical-radical coupling then afforded the formal [4+2] Diels-Alder cycloaddition adduct 60, which in turn underwent tautomerization to give 61. Reduction with tri-n-butyltin hydride then gave the ketal 62 in …

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Effect Of Pretreatment On The Performance Of Metal Contaminated Commercial Fcc Catalyst, Oguz Bayraktar Aug 2001

Effect Of Pretreatment On The Performance Of Metal Contaminated Commercial Fcc Catalyst, Oguz Bayraktar

Graduate Theses, Dissertations, and Problem Reports (ETD)

The performance of fluid catalytic cracking (FCC) catalyst decreases due to the severe negative effects of metal contaminants (e.g., nickel, vanadium and iron) deposited on the catalyst from the hydrocarbon feed. The metal contaminants cause an increase in the production of gas and coke at the expense of gasoline.;In this work the effect of pretreatment with hydrogen and methane gases on the performance of commercial, metal-contaminated, FCC equilibrium catalysts was investigated. Cracking reactions of both sour imported heavy gas oil (SIHGO) and n-hexadecane were carried out in a microactivity test (MAT) unit using three commercial equilibrium catalysts with different metals …

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Numerical Model For Determining The Wetting Front In A Clay Layer Of A Leaking Composite Barrier, Mustafa Eftelioglu Aug 2001

Numerical Model For Determining The Wetting Front In A Clay Layer Of A Leaking Composite Barrier, Mustafa Eftelioglu

Graduate Theses, Dissertations, and Problem Reports (ETD)

Composite barriers for hazardous and solid waste landfills are designed to minimize hydraulic transport of the contaminant leachate of the landfill; however, the geomembrane can be damaged during construction or otherwise contain imperfections from manufacturing. It is desirable to estimate the discharge characteristics and the flow width of such a leachate should leaks in the geomembrane occur.;Numerical solutions of the flow equations for unsaturated soil barriers can provide an understanding of the movement of a leachate through a composite barrier. The purpose of this investigation was to develop a computer model that simulated two-dimensional migration of leachate beneath holes in …

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