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Articles 36751 - 36780 of 302422

Full-Text Articles in Physical Sciences and Mathematics

Discussing Changes In Historical Human–Environmental Dynamics Through Ecosystem Services Interactions And Future Scenarios In A Rural-Mining Region Of Central Appalachians, Vincenzo Cribari Jan 2022

Discussing Changes In Historical Human–Environmental Dynamics Through Ecosystem Services Interactions And Future Scenarios In A Rural-Mining Region Of Central Appalachians, Vincenzo Cribari

Graduate Theses, Dissertations, and Problem Reports

The aim of this dissertation was to investigate how recent processes of land-change induced by humans contributed to the shaping and alteration of the current landscape in a headwater system of Central Appalachians in West Virginia (US), to understand the interactions and tradeoffs among ecosystems services and address potential solutions for targeting more sustainable human-environment interactions in a region that is deeply grounded on extractive economies. The multitiered objective was addressed through different research phases in order to unfold and disentangle a series of complex problems that the study area presents. Three main phases were used; they corresponded to distinct …

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Sources Of Variability And Uncertainty In Food-Energy-Water Nexus Systems, Heydi Calderon-Ambelis, Deepak R. Keshwani Jan 2022

Sources Of Variability And Uncertainty In Food-Energy-Water Nexus Systems, Heydi Calderon-Ambelis, Deepak R. Keshwani

Department of Biological Systems Engineering: Papers and Publications

A nexus approach contributes to the strategic allocation of resources to secure food, energy, and water for the world population. Integrated models considering the complex interactions across food, energy, and water (FEW) enhance decision-making and strategic planning towards resilience. However, a significant number of the existing integrated models leave unaddressed the inherent variability and uncertainty present in the FEW sectors. Here, we review the importance of characterizing variability over spatial and temporal scales and the importance of decreasing the uncertainty present within a FEW nexus systems. The review also discusses existing modeling tools that address variability and uncertainty on single …

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Devonian Upper Ocean Redox Trends Across Laurussia: Testing Potential Influences Of Marine Carbonate Lithology On Bulk Rock I/Ca Signals, Ruliang He, Maya Elrick, James Day, Wanyi Lu, Zunli Lu Jan 2022

Devonian Upper Ocean Redox Trends Across Laurussia: Testing Potential Influences Of Marine Carbonate Lithology On Bulk Rock I/Ca Signals, Ruliang He, Maya Elrick, James Day, Wanyi Lu, Zunli Lu

Faculty Publications-- Geography, Geology, and the Environment

The Devonian is characterized by major changes in ocean-atmosphere O2 concentrations, colonialization of continents by plants and animals, and widespread marine anoxic events associated with rapid d13C excursions and biotic crises. However, the long-term upper ocean redox trend for the Devonian is still not well understood. This study presents new I/Ca data from well-dated Lower Devonian through Upper Devonian limestone sections from the Great Basin (western Laurussia) and the Illinois Basin (central Laurussia). In addition, to better address potential influences of lithology and stratigraphy on I/Ca redox signals, I/Ca data are reported here as carbonate lithology-specific. Results indicate that lithologic …

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Maximum Likelihood Estimator Method To Estimate Flaw Parameters For Different Glass Types, Nabhajit Goswami Jan 2022

Maximum Likelihood Estimator Method To Estimate Flaw Parameters For Different Glass Types, Nabhajit Goswami

Dissertations, Master's Theses and Master's Reports

Glass is commonly used in architectural applications, such as windows and in-fill panels and structural applications, such as beams and staircases. Despite the popularity of structural glass use in buildings, an engineering design standard to determine the required component or member strength for design loads does not exist. Glass is a brittle material that lacks a well-defined yield or ultimate stress, unlike ductile materials. The traditional engineering methods used to design a ductile material cannot be used to design a glass component. Glass fails in tension primarily due to the presence of microscopic flaws present on the surface that acts …

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Spin Hall Effect Of Vorticity, Edward Schwartz, Hamed Vakili, Moaz Ali, Alexey Kovalev Jan 2022

Spin Hall Effect Of Vorticity, Edward Schwartz, Hamed Vakili, Moaz Ali, Alexey Kovalev

Department of Physics and Astronomy: Faculty Publications

Using mapping between topological defects in an easy-plane magnet and electrical charges, we study interplay between vorticity and spin currents. We demonstrate that the flow of vorticity is accompanied by the transverse spin current generation; an effect which can be termed as the spin Hall effect of vorticity. We study this effect across the BKT transition and establish the role of dissipation and spin nonconservation in the crossover from spin superfluidity to diffusive spin transport. Our results pave the way for low power computing devices relying on vorticity and spin flows that can propagate over long distances.

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Phenotypic Plasticity Of Geographically Central And Peripheral Populations Of Jefferson Salamanders (Ambystoma Jeffersonianum) In Response To Simulated Climate Change, Aaron Devine Jan 2022

Phenotypic Plasticity Of Geographically Central And Peripheral Populations Of Jefferson Salamanders (Ambystoma Jeffersonianum) In Response To Simulated Climate Change, Aaron Devine

Online Theses and Dissertations

Climate change will elicit various species responses as it causes habitats to change. Species with limited dispersal must respond to these changes “in place”, yet some biogeographical hypotheses indicate isolated and less abundant populations experience reduced gene flow and genetic diversity that may limit phenotypic plasticity, contrasting with evidence suggesting more variable habitats select for increased plasticity in peripheral populations. To gain insight into associations between range position and intensity of plasticity, mesocosm experiments were done to assess plasticity in larval growth, size at, and time to, metamorphosis, and survivorship in larval Ambystoma jeffersonianum salamanders from geographically core and peripheral …

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Fiber Optic Pressure Measurements Open Up New Experimental Possibilities In Hydrogeology, Carsten Leven, Warren Barrash Jan 2022

Fiber Optic Pressure Measurements Open Up New Experimental Possibilities In Hydrogeology, Carsten Leven, Warren Barrash

Geosciences Faculty Publications and Presentations

Fiber-optic (FO) technology is being used increasingly for measurement methods in a variety of environmental applications. However, FO pressure transducers are rarely used in hydrogeological applications. We review the current state of Fabry-Pérot interferometry-based FO pressure transducers, including their advantages and limitations, as another option for high-resolution pressure- or head-change measurements in conventional or advanced aquifer testing. Resolution and precision specifications of FO transducers meet or exceed commonly used non-FO pressure transducers. Due to their design, FO transducers can be used in small-diameter (innerdiameter≥1/4 inch) and continuous multichannel tubing (CMT), sampling points, multilevel packer systems, and Direct Push-based in situ …

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Footprints On The Prairie: Examining The Interlocking Land Histories Of The Liberty Prairie Reserve, Illinois, Anna M. Burns Jan 2022

Footprints On The Prairie: Examining The Interlocking Land Histories Of The Liberty Prairie Reserve, Illinois, Anna M. Burns

Scripps Senior Theses

This thesis begins with the local history of the Liberty Prairie, the land where I conducted the ecological field-work that I later discuss in my second thesis on soil microbiome diversity (“Examining Soil Microbial Diversity in Transition Zones Between Corn Fields and Restored Prairie in the Upper Midwest"). I examine the Indigenous histories of the land, and the conflicts between the Bodwéwadmi and Euro-American settlers that resulted in the land being farmed for cattle, corn, and soy for over a hundred and fifty years. I then take a step back and analyze the broader historical contexts of Midwestern Corn Belt …

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Synthesis And Characterization Of Ruthenium Complexes And Their Potential And Photosensitizers For Photodynamic Therapy, Keit Dine Jan 2022

Synthesis And Characterization Of Ruthenium Complexes And Their Potential And Photosensitizers For Photodynamic Therapy, Keit Dine

Master's Theses

Cancer is one of the leading causes of death in the world with over 10 million people dying of the disease every year. Inorganic complexes supported by platinum metal centers are often used in cancer treatment. However, these complexes lack selectivity for tumor cells. As such, other alternatives to platinum have been explored. Ruthenium (Ru) complexes are one of the most promising candidates due to their ability to be used as photosensitizing drugs in photodynamic therapy. Herein, we report the design, synthesis, and characterization of two novel ruthenium-based complexes. One compound is a Ru(II) homoleptic complex, while the other is …

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Sensitivity Analysis Of Basins Of Attraction For Gradient-Based Optimization Methods, Gillian King Jan 2022

Sensitivity Analysis Of Basins Of Attraction For Gradient-Based Optimization Methods, Gillian King

Honors Projects

This project is an analysis of the effectiveness of five distinct optimization methods in their ability in producing clear images of the basins of attraction, which is the set of initial points that approach the same minimum for a given function. Basin images are similar to contour plots, except that they depict the distinct regions of points--in unique colors--that approach the same minimum. Though distinct in goal, contour plots are useful to basin research in that idealized basin images can be inferred from the steepness levels and location of extrema they depict. Effectiveness of the method changes slightly depending on …

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Outlier Detection In Energy Datasets, Stephen Crawford Jan 2022

Outlier Detection In Energy Datasets, Stephen Crawford

Honors Projects

In the past decade, numerous datasets have been released with the explicit goal of furthering non-intrusive load monitoring research (NILM). NILM is an energy measurement strategy that seeks to disaggregate building-scale loads. Disaggregation attempts to turn the energy consumption of a building into its constituent appliances. NILM algorithms require representative real-world measurements which has led institutions to publish and share their own datasets. NILM algorithms are designed, trained, and tested using the data presented in a small number of these NILM datasets. Many of the datasets contain arbitrarily selected devices. Likewise, the datasets themselves report aggregate load information from building(s) …

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Accretion Onto A Black Hole At The Center Of A Neutron Star: Nuclear Equations Of State, Sophia Christina Schnauck Jan 2022

Accretion Onto A Black Hole At The Center Of A Neutron Star: Nuclear Equations Of State, Sophia Christina Schnauck

Honors Projects

A recent re-examination of Bondi accretion (see Richards, Baumgarte and Shapiro (2021)) revealed that, for stiff equations of state (EOSs), steady-state accretion can only occur for accretion rates exceeding a certain minimum. To date, this result has been explored only for gamma-law equations of state. Instead, we consider accretion onto a small black hole residing at the center of a neutron star governed by a more realistic nuclear EOS. We generalize the relativistic Bondi solution for such EOSs, approximated by piecewise polytropes, and thereby obtain analytical expressions for the accretion rates which were reflected in our numerical simulations. After taking …

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Tractor Test 2248: John Deere 9rt 470, Nebraska Tractor Test Lab Jan 2022

Tractor Test 2248: John Deere 9rt 470, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2261: John Deere 6140m, Nebraska Tractor Test Lab Jan 2022

Test 2261: John Deere 6140m, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2258: John Deere 9r 390, Nebraska Tractor Test Lab Jan 2022

Test 2258: John Deere 9r 390, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2257: John Deere 5125m, Nebraska Tractor Test Lab Jan 2022

Test 2257: John Deere 5125m, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2256: John Deere 5115m, Nebraska Tractor Test Lab Jan 2022

Test 2256: John Deere 5115m, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 2254: John Deere 5090m, Nebraska Tractor Test Lab Jan 2022

Test 2254: John Deere 5090m, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Nebraska Summary 1243s: Fendt 516 Vario Gen3 Diesel, Nebraska Tractor Test Lab Jan 2022

Nebraska Summary 1243s: Fendt 516 Vario Gen3 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Exploring The Privacy Dimension Of Wearables Through Machine Learning-Enabled Inference, Ulku Meteriz Yildiran Jan 2022

Exploring The Privacy Dimension Of Wearables Through Machine Learning-Enabled Inference, Ulku Meteriz Yildiran

Electronic Theses and Dissertations, 2020-2023

Today's hyper-connected consumers demand convenient ways to tune into information without switching between devices, which led the industry leaders to the wearables. Wearables such as smartwatches, fitness trackers, and augmented reality (AR) glasses can be comfortably worn on the body. In addition, they offer limitless features, including activity tracking, authentication, navigation, and entertainment. Wearables that provide digestible information stimulate even higher consumer demand. However, to keep up with the ever-growing user expectations, developers keep adding new features and interaction methods to augment the use cases without considering their privacy impacts. In this dissertation, we explore the privacy dimension of wearables …

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Computational Methods To Analyze Next-Generation Sequencing Data In Genomics And Metagenomics, Saidi Wang Jan 2022

Computational Methods To Analyze Next-Generation Sequencing Data In Genomics And Metagenomics, Saidi Wang

Electronic Theses and Dissertations, 2020-2023

This thesis focuses on two important computational problems in genomics and metagenomics with the public available next-generation sequencing data. One is about gene regulation, for which we explore how distal regulatory elements may interact with the proximal regulatory elements. The other is about metagenomics, in which we study how to reconstruct bacterial strain genomes from shotgun reads. Studying gene regulation, especially distal gene regulation, is important because regulatory elements, including those in distal regulatory regions, orchestrate when, where and how much a gene is activated under every experimental condition. Their dysfunction results in various types of diseases. Moreover, the current …

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Nebraska Summary: 1237 John Deere 6r 175 Diesel Infinitely Variable Transmission, Nebraska Tractor Test Lab Jan 2022

Nebraska Summary: 1237 John Deere 6r 175 Diesel Infinitely Variable Transmission, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Nebraska Tractor Summary: 1234 John Deere 6r 145, Nebraska Tractor Test Lab Jan 2022

Nebraska Tractor Summary: 1234 John Deere 6r 145, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Hamiltonian Approach To Modelling Interfacial Internal Waves Over Variable Bottom, Rossen Ivanov, Calin Martin, Michail Todorov Jan 2022

Hamiltonian Approach To Modelling Interfacial Internal Waves Over Variable Bottom, Rossen Ivanov, Calin Martin, Michail Todorov

Articles

We study the effects of an uneven bottom on the internal wave propagation in the presence of stratification and underlying non-uniform currents. Thus, the presented models incorporate vorticity (wave–current interactions), geophysical effects (Coriolis force) and a variable bathymetry. An example of the physical situation described above is well illustrated by the equatorial internal waves in the presence of the Equatorial Undercurrent (EUC). We find that the interface (physically coinciding with the thermocline and the pycnocline) satisfies in the long wave approximation a KdV–mKdV type equation with variable coefficients. The soliton propagation over variable depth leads to effects such as soliton …

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Escherichia Coli In Lake Erie: Impact On Lake Health, Mary Grmek Jan 2022

Escherichia Coli In Lake Erie: Impact On Lake Health, Mary Grmek

Williams Honors College, Honors Research Projects

Lake Erie is a vital resource for its surrounding area, and one of its most important purposes is as a recreational body of water. In determining whether Lake Erie’s water quality meets U.S. EPA standards, daily surveys and water samples were taken on behalf of the Lake County General Health District, as well as E. coli samples every other day. This paper quantified the E. coli count for both Mentor Headlands Beach and Fairport Harbor Beach in Lake County over the swimming seasons for 2020 and 2021, as well as evaluated which variables collected in daily surveys impact E. coli …

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Electrochemical Impedance Spectroscopy Analysis Of Corrosion Of Reinforcing Steel In Fly Ash Mortar By Means Of Transmission Line Modeling, Padraig Stack Jan 2022

Electrochemical Impedance Spectroscopy Analysis Of Corrosion Of Reinforcing Steel In Fly Ash Mortar By Means Of Transmission Line Modeling, Padraig Stack

Williams Honors College, Honors Research Projects

Electrochemical impedance spectroscopy (EIS) is an important non-destructive tool that allows for a deeper understanding of the electrochemical processes and mechanisms occurring in an electrochemical cell. Equivalent electrical circuits (EECs) are used to model the impedance data into electrical components, such as resistors and capacitors, on a circuit. Current potentiostat offers software packages that can analyze the frequency response, but the software only supports “simple” EEC that can be written as fixed electrical components in some combination of series and parallel. Park and Macdonald propose a transmission line model (TLM) that does not use lumped-element models, instead, the values of …

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Synthesis Of Rna Nucleotides Under Probable Prebiotic Conditions, Ryan Stimson Jan 2022

Synthesis Of Rna Nucleotides Under Probable Prebiotic Conditions, Ryan Stimson

Williams Honors College, Honors Research Projects

RNA being composed of multiple covalently linked nucleotides is thought to have been a precursor to life circa 4.3-3.8 billion years ago. Non-enzymatically formed adenosine monophosphate (AMP), more specifically, is a vitally important subtopic of the self-assembly of the first RNA sequence. The goal of this study was to synthesize AMP non-enzymatically under benign conditions that are likely to have existed on early Earth. In this experiment, 3’,5’-cAMP was successfully formed using wet-dry cycles at 80°C paired with the minerals zeolite beta, hydroxyapatite, and aerosil 300 in the presence of adenosine, urea, and pyrophosphate. A nuclear magnetic resonance spectrometer was …

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Self-Consistent Markovian Embedding Of Generalized Langevin Equations With Configuration-Dependent Mass And A Nonlinear Friction Kernel, Cihan Ayaz, Lucas Tepper, Roland R. Netz Jan 2022

Self-Consistent Markovian Embedding Of Generalized Langevin Equations With Configuration-Dependent Mass And A Nonlinear Friction Kernel, Cihan Ayaz, Lucas Tepper, Roland R. Netz

Turkish Journal of Physics

We consider a generalized Langevin equation (GLE) in which the deterministic force, the mass and the friction kernel are configuration-dependent, i.e. general nonlinear functions of the reaction coordinate. We introduce a projection operator that allows for a self-consistent Markovian embedding of such GLEs. Self-consistency means that trajectories generated by the Markovian embedding are described by a GLE with the same configuration-dependent deterministic force, mass and friction kernel. Using the projection operator, we derive a closed-form relation between the parameters of the Markovian embedding Langevin equations and the parameters of the GLE. This is accomplished by applying the projection operator formalism …

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Fluorometric Determination Of Ornidazole By Using Bsa Coated Copper Nanoclusters As A Novel Turn Off Sensor, Mehmetcan Bi̇lkay, Hayri̇ye Eda Şatana Kara Jan 2022

Fluorometric Determination Of Ornidazole By Using Bsa Coated Copper Nanoclusters As A Novel Turn Off Sensor, Mehmetcan Bi̇lkay, Hayri̇ye Eda Şatana Kara

Turkish Journal of Chemistry

A fluorescent probe based on bovine serum albumin stabilized copper nanoclusters (BSA-CuNCs) was developed for the selective and sensitive determination of ornidazole (ORN). The nanoclusters were synthesized via a one-pot hydrothermal process in basic media. The synthesized and characterized BSA-CuNCs have less than 3 nm particle size and exhibited blue emission at 405 nm when excited at 325 nm. Synthesized and characterized nanoclusters were successfully applied as a turn-off fluorescent probe for the determination of ORN in pharmaceutical dosage forms. The quenching mechanism created an was inner filter effect (IFE). The method was linear in the concentration range of 0.52-13.56 …

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A Bodipy Based Probe For The Reversible "Turn On" Detection Of Au(Iii) Ions, Muhammed Üçüncü Jan 2022

A Bodipy Based Probe For The Reversible "Turn On" Detection Of Au(Iii) Ions, Muhammed Üçüncü

Turkish Journal of Chemistry

A new "turn on" fluorescent probe for the rapid and selective detection of Au3+ ions over other metal ions was developed. The probe design was constructed on a BODIPY-2-aminopyridine skeleton showing a weak fluorescence emission signal which increased substantially after the coordination of Au3+ ions. The probe displayed remarkable sensing performances such as a low limit of detection (17 nM), a short response time (

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