Physical Sciences and Mathematics Commons^™

Physicochemical Properties And Availability Of Tahar-Güzelöz (Nevşehir) Diatomite, Ayşegül Yildiz, Ali Gürel, Dilan Okutan

Bulletin of the Mineral Research and Exploration

In this study, the use areas of diatomites located within the late Miocene-Pliocene volcano sedimentary units, which formed due to the volcanism and outcropped around the Tahar and Güzelöz localities, Nevşehir, were investigated in terms of raw materials. To do this, three stratigraphic sections were measured in the study area, one of which was measured in the Tahar area (TK), and two others were measured in the Güzelöz area (GÜ1 and GÜ2). Various physicomechanical, chemical, mineralogical and analytical methods were applied on the collected samples. The analysis results of diatomites in the investigated area were determined as follows; the amount …

Geochemical Characteristics Of Gabbroic Rocks In Zyarat In North East Of Iran, Ghassem Azi̇zzadeh, Mostafa Raghi̇mi̇, Seyed Jamal Shei̇khzakari̇aee, Aziz Rahi̇mi̇ Chakdel

Bulletin of the Mineral Research and Exploration

The mafic rocks outcrops exposed in the South of Gorgan, northeastern of Iran. These gabbroic rocks are intruded into the Middle–Upper Paleozoic sedimentary rocks and Gorgan schist units representing a part of the north Gondwana province. Petrography studies of these rocks show medium to coarse grained sizes and the texture varies from ophitic to intergranular under polarized microscope. The mineralogical composition of mafic dykes is dominated by large crystals of clinopyroxene + orthopyroxene + plagioclase and hornblende. These rocks can be classified as gabbroic rock. Geochemical studies show that these rocks have low to medium K₂O contents. The …

Mineral Chemistry, Whole-Rock Geochemistry And Petrology Of Eocene I-Type Shoshonitic Plutons In The Gölköy Area (Ordu, Ne Turkey), İrfan Temi̇zel, Emel Abdi̇oğlu Yazar, Mehmet Arslan, Abdullah Kaygusuz, Zafer Aslan

Bulletin of the Mineral Research and Exploration

The Eocene intermediate to felsic plutons are widespread in varying sizes and compositions throughout the Eastern Pontides Orogenic Belt in NE Turkey. Of these, two monzonitic bodies (namely the Eriko Tepe and Göl Tepe Plutons) in the Gölköy (Ordu) area, extend nearly in the orientation of NW-SE and E-W and were emplaced into the Upper Cretaceous and/or Eocene volcanic and sedimentary rocks. Petrographically, the studied monzonitic plutons are compositionally fine to medium grained monzonite, monzodiorite and subordinate quartz-monzonite. They consist of plagioclase (An_35-67), K-feldspar (Or_61-96), quartz, clinopyroxene (Wo_28-49En_35-51Fs_10-25), biotite (Mg#: …

Evaluation Of Thrace Region Fine Coal Tailings, Murat Olgaç Kangal, Mustafa Özer, Fırat Burat, Soner Akin

Bulletin of the Mineral Research and Exploration

The 79.9% of lignites in Turkey possesses a calorific value lower than 2500 kcal/kg. In order to reduce the energy dependence of the country, it would be right to evaluate these lignite reserves of 11.8 billion tons by effective coal preparation methods and use them with clean coal combustion systems together with developing technology. A typical coal preparation plant produces material within a ratio of 20% of the feed coal below 0.5 mm. Generally, due to the high cost, the gain of the fugitive coal in the product under this size is not preferred but this size group can be …

Petrography, Mineral Chemıstry And Crystallizatıon Conditions Of Cenozoic Plutonic Rocks Located To The North Of Bayburt (Eastern Pontıdes, Turkey), Abdullah Kaygusuz, Cem Yucel, Mehmet Arslan, Ferkan Sipahi, Irfan Temizel, Gokhan Cakmak, Z. Samet Guluglu

Bulletin of the Mineral Research and Exploration

The Eastern Pontides comprises of many intrusive bodies varying in composition, size and age from Paleozoic to Cenozoic. Those of especially Cenozoic aged ones are commonly observed in the southern part while are rarely exposed in the northern part of the Eastern Pontides. In this study, the petrographical and mineral chemistry properties of Çiçekli, Somarova, Sorkunlu, Şaşurluk, Aydıntepe, Kemerlikdağı and Pelitli plutons located to the north of Bayburt area are determined, and the crystallization conditions of the studied bodies were estimated by means of thermobarometer calculations. The studied plutons extend mostly NE-SW directions and are approximately ellipse in shapes. The …

An Ore Adit Planning With The Help Of Three Dimensional Ore Body Modeling: A Case Study From Çulfa Çukuru Pb-Zn-Cu-Ag Deposit, Sinan Akiska, Elif Akiska

Bulletin of the Mineral Research and Exploration

Çulfa Çukuru Pb-Zn-Cu-Ag mineralization has occurred along the metamorphic and metamorphic-dacitic volcanic rock contacts of the Sakarya zone on the Biga Peninsula. The base metal mineralization (Pb-Zn-Cu-Ag±Au) developed along the contact and fracture planes of these rocks can be observed as veins, lenses and disseminated ore geometries in the calc-silicate rock assemblages. Base metal mineralizations are mainly controlled lithologically and are generally associated with recrystallized limestones. In this study, the surface and the subsurface were modeled using the topographical data and the geochemical data (%Pb and %Zn) collected from 42 boreholes of Çulfa Çukuru which is located 20 km South-Southeast …

Optimization Of Some Parameters On Desulfurization Process Of Muğla Yatağan Bağyaka Lignite By Ultrasonic Waves, İlkay Ünal Sansar

Bulletin of the Mineral Research and Exploration

In this study, the desulfurization process developed using ultrasonic waves for Muğla Yatağan Bağyaka lignite had the optimum conditions for parameters affecting the ash and sulfur removal potentials determined with the Surface Response Method and a model created. The process parameters to obtain optimum desulfurization and ash removal were chosen as the ultrasonic treatment time, solid content, concentration of chemical reactive (H₂O₂) and reactive volume, and the optimum values were determined. Using this data with the aid of the Design Export 7.0 program, the regression model was found as a second degree polynomial equation. The coefficients …

The Evolution Of Computational Propaganda: Trends, Threats, And Implications Now And In The Future, Holly Schnader

Senior Honors Projects, 2010-2019

Computational propaganda involves the use of selected narratives, social networks, and complex algorithms in order to develop and conduct influence operations (Woolley and Howard, 2017). In recent years the use of computational propaganda as an arm of cyberwarfare has increased in frequency. I aim to explore this topic to further understand the underlying forces behind the implementation of this tactic and then conduct a futures analysis to best determine how this topic will change over time. Additionally, I hope to gain insights on the implications of the current and potential future trends that computational propaganda has.

My preliminary assessment shows …

Human Thermal Comfort In Transition Space, Asawari Anil Pawar

UNLV Theses, Dissertations, Professional Papers, and Capstones

ABSTRACT

HUMAN THERMAL COMFORT IN TRANSITION SPACES

Objective: To evaluate and identify the relationship between personal factors and the climatic conditions that influence the human thermal comfort in transition spaces and suggest solutions for adaptation of the built environment, that would encourage active and healthy living in the tourist as well as local community.

Background:

By 2050, there is a prediction that two-thirds of the world population will be living in urban areas, which would add more than 2.5 billion people living in cities (Melnikov et al., 2017). Since Las Vegas is one of the fastest growing cities in Nevada, …

Precaspian Isthmus Emergence Triggered The Early Sakmarian Glaciation (Paleontologic, Sedimentologic And Geochemical Proxies), Vladimir I. Davydov

Geosciences Faculty Publications and Presentations

The sub-meridional seaway that connected Paleo-Arctic and Paleo-Tethys basins was one of the most important geographical attributes of the Late Paleozoic Pangea landscape, paleogeography and paleoclimate. Existing models about the timing of the disconnection of the Paleo-Arctic and the Paleo-Tethyan oceans is very controversial and poorly documented. Warm-water benthic foraminifera (WWBF) were utilized to establish the precise timing of the closure of the Urals-Precaspian-Paleo-Tethys Seaway (UPTS) during Cisuralian time. The WWBF of Paleo-Tethys and those of the Ural-Precaspian Basins during the Gzhelian-Asselian, display a considerably high level of similarity. Beginning from the Sakmarian, the faunas of these two regions became …

Radiolabeled Nanohydroxyapatite As A Platform For The Development Of New Pet Imaging Agents, Stacy Lee Queern

Arts & Sciences Electronic Theses and Dissertations

Positron emission tomography (PET) imaging utilizes drugs labeled with positron emitters to target and evaluate different biological processes occurring in the body. Tailoring medicine to the individual allows for higher quality of care with better diagnosis and treatment and is a key purpose for advancing research into developing new platforms for PET imaging agents. A PET nuclide of high interest for the development of these agents is 89Zr. This can be attributed to the long half-life of 3.27 days and low positron energy of 89Zr.

In this work, we developed a production method for 89Zr using Y sputtered coins that …

Towards Engineering Advanced Nanomaterials: Elucidating Fundamental Particle Behavior In Water And Critical Sorption Dynamics, Changwoo Kim

McKelvey School of Engineering Theses & Dissertations

As advanced nanomaterials, inorganic-organic nano composites have received great interest as potential platform (nano) structures for sensor, catalyst, sorbent, and environmental applications. Here, my Ph.D. research has focused on the design, synthesis, and characterization of advanced water-stable engineered metal-oxide nanoparticles functionalized by organic frames for environmental applications. For the environmental applications, I have evaluated particleoptimized sorption processes for the remediation and separation of arsenic, chromium, and uranium under environmentally relevant conditions. More specifically, I have explored the critical role of organic coating on sorption mechanisms and performances using engineered iron oxide -based, manganese oxide -based, and manganese ferrite -based (core) …

Kcnq1/Kcne1 Interaction In The Cardiac Iks Channel And Its Physiological Consequences, Jiajing Xu

McKelvey School of Engineering Theses & Dissertations

Dynamic conformational changes of ion channel proteins during activation gating determine their function as carriers of current. The relationship between these molecular movements and channel function over the physiological timescale of the action potential (AP) has not been fully established due to limitations of existing techniques. We constructed a library of possible cardiac IKs protein conformations and applied a combination of protein segmentation and energy linearization to study this relationship computationally. Simulations reproduced the effects of the beta-subunit (KCNE1) on the alpha-subunit (KCNQ1) dynamics and function, observed in experiments. Mechanistically, KCNE1 increased the probability of “visiting” conducting pore conformations on …

Riding The Wave Of Microplastics In Bermuda, Molly E. Riihiluoma

Pell Scholars and Senior Theses

The presence of marine debris and microplastics in the Earth’s oceans are a global environmental issue. Bermuda’s location in the middle of the North Atlantic Gyre makes it the perfect case study for this work. As the crisis unfolds, Bermuda’s environment, economy, and population are at risk of witnessing firsthand the effects of plastic pollution. This paper relies on scholarly research as well as anecdotal evidence from retail stores and locals to compile information in order to provide necessary recommendations to benefit Bermuda’s ocean health. This research evaluates the pros and cons of policies which could mitigate the problem. Analysis …

Learning About Large Scale Image Search: Lessons From Global Scale Hotel Recognition To Fight Sex Trafficking, Abby Stylianou

McKelvey School of Engineering Theses & Dissertations

Hotel recognition is a sub-domain of scene recognition that involves determining what hotel is seen in a photograph taken in a hotel. The hotel recognition task is a challenging computer vision task due to the properties of hotel rooms, including low visual similarity between rooms in the same hotel and high visual similarity between rooms in different hotels, particularly those from the same chain. Building accurate approaches for hotel recognition is important to investigations of human trafficking. Images of human trafficking victims are often shared by traffickers among criminal networks and posted in online advertisements. These images are often taken …

Mercury In Big Cypress Bayou And Caddo Lake Watersheds In Marion And Harrison Counties Texas, Joseph Watkins

Electronic Theses and Dissertations

Caddo Lake has been included on the Texas Commission on Environmental Quality 303(d) list for impairment due to mercury (Hg) content since 1996. One of the primary tributaries, Big Cypress Bayou, flows across Eocene-aged rocks and sediments associated with the Wilcox Group; the Wilcox is of interest because it contains lignite coal, which has a direct link to mercury. Previous research has focused on dry deposition from fossil fuel combustion as the primary source of mercury but has not addressed the potential watershed contribution to mercury concentrations in Caddo Lake.

Big Cypress Bayou flows through Harrison and Marion counties in …

Influencing Hawai‘I Hotel Patrons To Use Reef-Safe Sunscreens, Rochelle Good

UNLV Theses, Dissertations, Professional Papers, and Capstones

The health of Hawaiian coral reefs is threatened by pollution from common sunscreen ingredients such as oxybenzone. Hawai‘i hotel patrons using sunscreens with harmful ingredients contaminate coral reefs when these products wash off while swimming or bathing. Reef-safe sunscreens are alternative sunscreens that provide effective sun protection while averting damage to coral reefs. The purpose of this research was to determine the dominant factors leading to the pro-environmental behavior of using reef-safe sunscreen and identify practices that Hawai‘i hotel operators could implement to influence patrons to engage in this behavior. This research applied an integrative conceptual framework to model pro-environmental …

Petrogenesis Of Enriched And Intermediate Poikilitic Shergottites: From Magmatic Source To Emplacement, Rachel Rahib

UNLV Theses, Dissertations, Professional Papers, and Capstones

Poikilitic shergottites, making up >20% of martian meteorites, likely represent a significant composition of the martian crust, as intrusive gabbroic rocks. To further constrain petrogenetic relationships amongst enriched and intermediate poikilitic shergottites, we utilize bulk rock trace element compositions, mineral major element compositions, phosphorus maps of olivine grains, oxygen fugacity (ƒO2) values, subsolidus equilibration temperatures, and quantitative textural analyses, of the most comprehensive suite of poikilitic shergottites yet (11 samples), including three newly recovered samples (Northwest Africa [NWA] 11065, NWA 11043, NWA 10961). Although petrographically light rare earth element (LREE) enriched and intermediate poikilitic shergottites are similar, distinct LREE abundances …

Employee Perceptions Of Organizational Corporate Responsibility And Their Effect On Employee Organizational Commitment, Lisa R. Davis

UNLV Theses, Dissertations, Professional Papers, and Capstones

The debate over whether organizations play a part in society beyond economic profit has been a major focus of research in corporate social responsibility (CSR). These debates have been mainly looked at from the macro (societal) or the meso (institutional) level. Very little research has been done on the role of the firm and looking at CSR from the micro (individual) level. Questions regarding the role of work for employees, securing economic benefits or making a difference in the world, would vary greatly depending on the individual and the importance they place on these areas in their own lives. Scholars …

Studies Of Inner-Shell Chemistry Of Mercury Based Compounds At Extreme Conditions, Sarah Schyck

UNLV Theses, Dissertations, Professional Papers, and Capstones

It has been theoretically predicted that when mercury difluoride (HgF2) is pressurized to above 50 GPa in the presence of molecular fluorine, it will most likely transform into mercury tetrafluoride (HgF4), thus mercury will behave as a transition element at high pressure. However, there is no experimental evidence verifying this prediction yet. To begin with, the crystalline properties of pure HgF2 at high pressure were not experimentally established. In this thesis, the high pressure structural properties of HgF2 are investigated by means of synchrotron X-ray powder diffraction. Our results reveal that the predicted, ambient cubic structure of HgF2 with the …

The Use Of Chemical Element Fingerprints To Investigate The Transformation Of Lake Sediments To Land Soils In Drying Lakes: A Case Study At Lake Mead, Nevada, Ji Hye Park

UNLV Theses, Dissertations, Professional Papers, and Capstones

Drying lakes are a worldwide catastrophe. The goals of this dissertation research were (1) to investigate whether chemical fingerprints of lake sediments, and nearby land soils, could be established by the analysis of 44 chemical elements, moisture content, Eh, pH, and leachable anions and if so, (2) whether the fingerprints could help explain the process of physical and chemical changes in the lake sediments as they became soils when the lake's water level fell and the anoxic sediments were exposed to the air and weather.

Lake Mead was chosen to model drying lakes because its water level has fallen over …

Optimization Of Useful Hard X-Ray Photochemistry, David Lewis Goldberger

UNLV Theses, Dissertations, Professional Papers, and Capstones

X-ray induced damage is generally considered a nuisance, but in the field of Useful Hard X-ray Photochemistry we harness the highly ionizing and penetrating properties of hard X-rays (> 7 keV) to initiate novel photochemical decomposition and synthesis at ambient and extreme conditions. Preliminary experiments suggest that the energy of irradiating photons and the sample pressure play roles in determining the nature of X-ray induced damage. Here, we present the X-ray energy dependence of damage induced in strontium oxalate, strontium nitrate, and barium nitrate, as well as the pressure dependence of X-ray induced damage of strontium oxalate. Our results indicate …

Mechanisms Of Calcium Phosphate Mineralization On Biological Interfaces And Their Engineering Applications, Doyoon Kim

McKelvey School of Engineering Theses & Dissertations

All living organisms utilize phosphorus (P) as an essential component of their cell membranes, DNA and RNA, and adenosine triphosphate. Bones, in addition to bearing loads, play an important role in balancing P levels in our bodies. In bones, a network of collagen templates and calcium phosphate (CaP) nanocrystals builds hierarchical levels, from nano- to macroscale. Within this architecture, the thermodynamic properties of CaP minerals are influential. Despite the importance of nucleation, growth, and crystallization in collagen structures for tissue development, little kinetic study of these processes has been conducted due to the limited in situ techniques for monitoring these …

Improve The Low Energy Sensitivity Of The Hawc Observatory, Zhixiang Ren

Optical Science and Engineering ETDs

The high altitude water cherenkov gamma-ray observatory (HAWC) has been fully operational since March of 2015 in Mexico at 4,100 meters above sea level on the hillside of the Sierra Negra Volcano. It consists of an array of 300 water cherenkov detectors, each equipped with four photo-multiplier tubes. HAWC operates 24-hours per day with a wide field-of-view (FOV, ∼ 2 sr) and a high duty cycle (∼ 95%). These make it a powerful survey and monitoring experiment for mapping the gamma ray sky at very high energies (VHE, 100 GeV to 100 TeV) and to study sources with varying intensities. …

Post-Glacial Terraces Of The Marmara Sea And Water Exchange Periods, Vedat Ediger, Emin Demi̇rbağ, Semih Ergi̇ntav, Sedat İnan, Ruhi Saatcılar

Bulletin of the Mineral Research and Exploration

Semi-enclosed Marmara Sea is a passage between the Aegean Sea (Northeastern Mediterranean Sea) and the Black Sea. The Marmara Sea is connected to the Black Sea and the Aegean Sea through the İstanbul Strait (Bosphorus) and Çanakkale Strait (Dardanelles), respectively. Despite the fact that the late Pleistocene-Holocene connections between the seas have been explored by many scientists, there are still uncertainties about the nature and timing of the connections. Within the scope of this study, a new approach has been displayed for post-glacial connections between the Black Sea, Marmara Sea, and the Aegean Sea. This study is based on 80 …

Geology And Critical Review Of The Upper Cretaceous Zagros Chalky Limestone (Kometan Formation) From Sulaimani Governorate, Northeastern Iraq, Kamal Haji Karim Kari̇m, Sherzad Tofeeq Al-Barzinjy, Polla Azad Khanaqa

Bulletin of the Mineral Research and Exploration

The chalky limestone (Kometan Formation) is aged Late Turonian–Middle Campanian and cropping out in the High, Imbricate and Thrust Zones of northeastern Iraq, Sulaimani area. It laterally changes to Bekhme and Mushurah formations toward northwest and west Iraq respectively and its reefal equivalents occurs too in subsurface of Central Iraq in the oil fields. Stratigraphically, it is located between Shiranish Formation (Middle-Late Campanian), at the top, and Gulneri Formation (Late Cenomanian-Early Turonian) at its base. It has the thickness of about 40-120 meter and deposited in pelagic realm. All previous studies have defined it as well bedded and fine grain …

Nanopower Analog Frontends For Cyber-Physical Systems, Kenji Aono

McKelvey School of Engineering Theses & Dissertations

In a world that is increasingly dominated by advances made in digital systems, this work will explore the exploiting of naturally occurring physical phenomena to pave the way towards a self-powered sensor for Cyber-Physical Systems (CPS). In general, a sensor frontend can be broken up into a handful of basic stages: transduction, filtering, energy conversion, measurement, and interfacing. One analog artifact that was investigated for filtering was the physical phenomenon of hysteresis induced in current-mode biquads driven near or at their saturation limit. Known as jump resonance, this analog construct facilitates a higher quality factor to be brought about without …

Computational Explorations Of Information And Mechanism Design In Markets, Zhuoshu Li

McKelvey School of Engineering Theses & Dissertations

Markets or platforms assemble multiple selfishly-motivated and strategic agents. The outcomes of such agent interactions depend heavily on the rules, regulations, and norms of the platform, as well as the information available to agents. This thesis investigates the design and analysis of mechanisms and information structures through the ``computational lens'' in both static and dynamic settings. It both addresses the outcome of single platforms and fills a gap in the study of the dynamics of multiple platform interactions.

In static market settings, we are particularly interested in the role of information, because mechanisms are harder to change than the information …

Photophysical Characterization And Wavelength Tuning Of Natural And Synthetic Oxobacteriochlorins And Biohybrids, Don Hood

Arts & Sciences Electronic Theses and Dissertations

ABSTRACT OF THE DISSERTATION

Photophysical Characterization and Wavelength Tuning of Natural and Synthetic Oxobacteriochlorins and Biohybrids

By

Donald L. Hood

Doctor of Philosophy in Chemistry

Washington University in St. Louis, 2018

Dr. Dewey Holten, Chairperson

Herein is discussed the theoretical and practical unpinnings of photophysical behaviors and kinetic constants for tetrapyrrole macrocycles, to wit, porphyrins, chlorins, and bacteriochlorins. Understanding the characteristic photophysical response of tetrapyrroles to changes in environment or substituents is important to designing synthetic chromophores with tunable absorption wavelengths and for preparing useful biohybrids of natural photosynthetic light antennas combined with unnatural chromophores attached to the light antenna …

Stratigraphic Control Of Landscape Response To Base-Level Fall, Young Womans Creek, Pennsylvania, Usa, Roman A. Dibiase, Alison R. Denn, Paul R. Bierman, Eric Kirby, Nicole West, Alan J. Hidy

College of Arts and Sciences Faculty Publications

Landscapes are thought to respond to changes in relative base level through the upstream propagation of a boundary that delineates relict from adjusting topography. However, spatially-variable rock strength can influence the topographic expression of such transient landscapes, especially in layered rocks, where strength variations can mask topographic signals expected due to changes in climate or tectonics. Here, we analyze the landscape response to base-level fall in Young Womans Creek, a 220 km2 catchment on the Appalachian Plateau, USA underlain by gently folded Paleozoic sedimentary rocks. We measured in situ 10Be concentrations in stream sands from 17 nested watersheds, and used …