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Articles 28111 - 28140 of 302422

Full-Text Articles in Physical Sciences and Mathematics

Analytic Solution Of 1d Diffusion-Convection Equation With Varying Boundary Conditions, Małgorzata B. Glinowiecka-Cox Jun 2022

Analytic Solution Of 1d Diffusion-Convection Equation With Varying Boundary Conditions, Małgorzata B. Glinowiecka-Cox

University Honors Theses

A diffusion-convection equation is a partial differential equation featuring two important physical processes. In this paper, we establish the theory of solving a 1D diffusion-convection equation, subject to homogeneous Dirichlet, Robin, or Neumann boundary conditions and a general initial condition. Firstly, we transform the diffusion-convection equation into a pure diffusion equation. Secondly, using a separation of variables technique, we obtain a general solution formula for each boundary type case, subject to transformed boundary and initial conditions. While eigenvalues in the cases of Dirichlet and Neumann boundary conditions can be constructed easily, the Robin boundary condition necessitates solving a transcendental algebraic …


Michigan Conifer Growers’ Perspectives On Disease Management, Emily S. Huff, Monique L. Sakalidis Jun 2022

Michigan Conifer Growers’ Perspectives On Disease Management, Emily S. Huff, Monique L. Sakalidis

The Journal of Extension

A survey of commercial nursery and Christmas tree growers was implemented online and by mail in 2018 to understand disease issues and information preferences. Overall, the majority of the respondents reported that they prefer online sources of information and many are using Extension bulletins and sources. Cultural, chemical, and weed control methods were considered extremely effective by participants and very few used biological control methods to control disease. Participants identified spruce decline, boxwood blight, and hemlock woolly adelgid as emerging disease threats, so future information to growers should focus on identification and management of these threats.


The Inextricability Of Students’ Mathematical And Physical Reasoning In Quantum Mechanics Problems, Kaitlyn Stephens Serbin, Megan Wawro Jun 2022

The Inextricability Of Students’ Mathematical And Physical Reasoning In Quantum Mechanics Problems, Kaitlyn Stephens Serbin, Megan Wawro

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

Reasoning with mathematics plays an important role in university students’ learning throughout their courses in the scientific disciplines, such as physics. In addition to understanding mathematical concepts and procedures, physics students often must mathematize physical constructs in terms of their associated mathematical structures and interpret mathematical entities in terms of the physical context. In this study, we investigate physics students’ reasoning about mathematics in relation to physics content addressed in two quantum mechanics problems. Through qualitative analysis of interview data from twelve students, results show that 1) students use intricate, nonuniform problem-solving methods with reasoning that moves fluidly between structural …


Forest Aboveground Biomass In The Southwestern United States From A Misr Multi-Angle Index, 2000–2015, Mark Chopping, Zhousen Wang, Crystal Schaaf, Michael A. Bull, Rocio R. Duchesne Jun 2022

Forest Aboveground Biomass In The Southwestern United States From A Misr Multi-Angle Index, 2000–2015, Mark Chopping, Zhousen Wang, Crystal Schaaf, Michael A. Bull, Rocio R. Duchesne

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Multi-angle surface reflectance data from the NASA Jet Propulsion Laboratory Multi-angle Imaging Spectro-Radiometer (MISR) were used to map aboveground biomass density (AGB, Mg ha−1) in the forests of the southwestern United States inter-annually from 2000 to 2015. The approach uses a multi-angle index that has a loge relationship with AGB estimates in the National Biomass and Carbon Dataset 2000 (NBCD 2000). MISR Level 1B2 Terrain radiance data from May 15–June 15 of each year were converted to mapped surface bidirectional reflectance factors (BRFs) and leveraged to adjust the kernel weights of the RossThin-LiSparse-Reciprocal Bidirectional Reflectance Distribution Function (BRDF) …


Goursa Type Problem For A System Of Equations Of Poroelasticity, Kholmatzhon Imomnazarov, Lochin Khujayev, Zoyir Yangiboev Jun 2022

Goursa Type Problem For A System Of Equations Of Poroelasticity, Kholmatzhon Imomnazarov, Lochin Khujayev, Zoyir Yangiboev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

In this paper, in the description of the test process, we assume that the change in the temperature field of the environment will not affect the acoustic characteristics of the system are determined by the compressibility and viscosity of the fluid. Let us consider the effects caused by the shear modulus and coefficient of interfacial friction.


Enhancing Vanadium Redox Battery Performance Using Tungsten-Bismuth-Based Oxide Nanostructures As Electrode Modifiers, Taher Al Najjar Jun 2022

Enhancing Vanadium Redox Battery Performance Using Tungsten-Bismuth-Based Oxide Nanostructures As Electrode Modifiers, Taher Al Najjar

Theses and Dissertations

Renewable energy power plants require high efficiency conversion and storage systems that can store high amounts of energy and can be integrated with the electrical grid. Vanadium redox flow batteries are very promising for this application. However, one major drawback of VRFBs is their low power density which means that right now they cannot replace non-renewable energy sources. Different carbon materials are used as electrodes in VRFBs and each carbon material affects the battery’s performance in a different way. Modification of these electrodes can increase the power density of the battery. Some metal oxides like tungsten oxide can enhance vanadium …


Evidence For Multiple Potential Drivers Of Increased Phosphorus In High-Elevation Lakes, J. Scholz, Janice Brahney Jun 2022

Evidence For Multiple Potential Drivers Of Increased Phosphorus In High-Elevation Lakes, J. Scholz, Janice Brahney

Watershed Sciences Faculty Publications

Total phosphorus (TP) concentrations have increased in many remote mountain waterbodies across the western United States, and reports of algal blooms in these systems have increased in frequency. Explanations for observed TP increases are uncertain, and typical landscape drivers, such as agricultural/urban runoff, are implausible. We investigated multiple atmospheric and terrestrial-P loading mechanisms to explain the observed decadal increase in TP, including a novel hypothesis that warming soils may lead to elevated P fluxes to receiving water bodies. Using northern Utah mountains ranges as a case study, we measured prospective inputs of total and bioavailable P via dust deposition. Terrestrial …


Strongly M-Subharmonic Functions On Complex Manifolds, Sukrotbek Kurbonboyev Jun 2022

Strongly M-Subharmonic Functions On Complex Manifolds, Sukrotbek Kurbonboyev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

This article is devoted to the definition and study of strongly m-subharmonic (shm) functions on complex manifolds. A definition of strongly m-subharmonic functions on a Stein manifold is introduced and some basic properties are proven.


75-Th Anniversary Of V.V.Aseev, Azimbay Sadullaev, Azizjon Varisov, Alexander Mednykh, Tetenov Andrey Jun 2022

75-Th Anniversary Of V.V.Aseev, Azimbay Sadullaev, Azizjon Varisov, Alexander Mednykh, Tetenov Andrey

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

No abstract provided.


Analogue Of The Mittag-Leffler Theorem For A(Z)-Analytic Functions, Muhayyo Ne'matillayeva Jun 2022

Analogue Of The Mittag-Leffler Theorem For A(Z)-Analytic Functions, Muhayyo Ne'matillayeva

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

We consider A(z)-analytic functions in case when A(z) is antiholomorphic function. For A(z)-analytic functions analog of the Mittag-Leffler theorem is proved.


Existence Of Boundary Values Of Hardy Class Functions H1A, Nasridin Zhabborov, Shokhruh Khursanov, Behzod Husenov Jun 2022

Existence Of Boundary Values Of Hardy Class Functions H1A, Nasridin Zhabborov, Shokhruh Khursanov, Behzod Husenov

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

We consider A(z)-analytic functions in case when A(z) is antianalytic function. In this paper, the Hardy class for A(z)-analytic functions are introduced and for these classes, the boundary values of the function are investigated. For the Hardy class of functions H1A, an analogue of Fatou's theorem was proved about that the bounded functions have the boundary values. As the main result, the boundary uniqueness theorem for Hardy classes of functions H1A is proven.


Algorithmic Criterion Of Locally Finite Separability Of Algebras Represented Over Equivalence Α2 ∪ Id Ω, Sarvar Zhavliev Jun 2022

Algorithmic Criterion Of Locally Finite Separability Of Algebras Represented Over Equivalence Α2 ∪ Id Ω, Sarvar Zhavliev

Bulletin of National University of Uzbekistan: Mathematics and Natural Sciences

It has been established that for equivalences of the form α2 ∪ id ω, the locally finite separability of any universal algebra represented over it is equivalent to the immune of the complement α. It is shown that for finitely separable algebras this criterion does not meet.


2022 Final Unreclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc. Jun 2022

2022 Final Unreclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Draft Final 2021 Unreclaimed Sites Sampling Ur-35 Site Evaluation Summary Report, Pioneer Technical Services, Inc. Jun 2022

Draft Final 2021 Unreclaimed Sites Sampling Ur-35 Site Evaluation Summary Report, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Silver Bow Creek/Butte Area Npl Site Butte Priority Soils Operable Unit, Pioneer Technical Services, Inc. Jun 2022

Silver Bow Creek/Butte Area Npl Site Butte Priority Soils Operable Unit, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Revised Draft Final Butte Reclaimed Areas Maintenance And Monitoring (M&M) Plan In Accordance With Butte Reclamation Evaluation System (Bres), Pioneer Technical Services, Inc. Jun 2022

Revised Draft Final Butte Reclaimed Areas Maintenance And Monitoring (M&M) Plan In Accordance With Butte Reclamation Evaluation System (Bres), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Shadows Of A Schwarzschild Black Hole Surrounded By A Spherically Symmetric Dark Matter, Ahmad Ibrahim Jun 2022

Shadows Of A Schwarzschild Black Hole Surrounded By A Spherically Symmetric Dark Matter, Ahmad Ibrahim

Theses and Dissertations

In this thesis, using general relativity, the null geodesics and black hole shadow of a spherically symmetric configuration of a black hole (surrounded by a dark matter shell) are studied. First, the standard

results of the photon sphere of Schwarzschild de-Sitter black hole is revisited and analyzed more carefully. Secondly, using an ansatz (piecewise metric function) commonly used in the literature to describe the mass distribution of the spherically symmetric black hole - dark matter configuration, the null geodesics through vacuum and dark matter are analyzed. Assuming an observer located at a finite distance from the black hole outside the …


Policing By Proxy: Interrogating Big Tech's Role In Law Enforcement, Claire Elizabeth Jun 2022

Policing By Proxy: Interrogating Big Tech's Role In Law Enforcement, Claire Elizabeth

University Honors Theses

Predictive policing, sometimes referred to as data-driven or actuarial policing, is a method of policing that uses a risk-based approach to law enforcement. For-profit technology companies market proprietary risk assessment algorithms to law enforcement organizations as tools meant to proactively mitigate crime. Using data collected from a vast array of sources, both personal and public, police are able to "predict" the likelihood of criminal activity in a given area using these algorithms. Proponents claim that risk assessment tools have the potential to fight crime with unbiased accuracy and speed by predicting when, where, and whom to police by relying on …


Quantum Decoherence In Time-Dependent Anharmonic Systems, Ty Beus Jun 2022

Quantum Decoherence In Time-Dependent Anharmonic Systems, Ty Beus

Theses and Dissertations

This dissertation studies quantum decoherence in anharmonic oscillator systems to monitor and understand the way the systems evolve. It also explores methods to control the systems' evolution, and the effects of decoherence when applicable. We primarily do this by finding the time evolution of the systems using their Lie algebraic structures. We solve for a generalized Caldirola-Kanai Hamiltonian, and propose a general way to produce a desired evolution of the system. We apply the analysis to the effects of Dirac delta fluctuations in mass and frequency, both separately and simultaneously. We also numerically demonstrate control of the generalized Caldirola-Kanai system …


A Simplified Model For The Intermediate Structure Of Strong Fire Whirls, Forman A. Williams Jun 2022

A Simplified Model For The Intermediate Structure Of Strong Fire Whirls, Forman A. Williams

Progress in Scale Modeling, an International Journal

A model is described for the overall structure of intense fire whirls, based on a spatially evolving vortex, with circulation enhancement driven by the axial acceleration of low-density gas in the core through the axial pressure gradient. The axial acceleration increases the entrainment rate into the core which, through mass conservation, increases the circulation if the angle between the tangential and radial velocity components remains fixed. The two-zone model employs general balance equations for regions inside and outside a cylinder of fixed radius, each inviscid, the inside region being presumed to have a constant density small compared with the (constant) …


Stereocontrolled Access To Δ-Lactone-Fused-Γ-Lactams Bearing Angular Benzylic Quaternary Stereocenters, Timothy K. Beng, Morgan J. Rodriguez, Claire Borg Jun 2022

Stereocontrolled Access To Δ-Lactone-Fused-Γ-Lactams Bearing Angular Benzylic Quaternary Stereocenters, Timothy K. Beng, Morgan J. Rodriguez, Claire Borg

All Faculty Scholarship for the College of the Sciences

C-fused γ-lactam-lactones are resident in several bioactive molecules, including anticancer agents such as omuralide. In this embodiment, we report mild conditions for the catalytic halolactonization of lactam-tethered 5-aryl-4(E)-pentenoic acids. The use of dichloromethane as the solvent and Ph3PS as the catalyst led to predominant 6-endo-trig cyclization and furnished the trans-fused-γ-lactam-δ-lactones. The transformation is modular, regioselective, chemoselective, and diastereoselective. The γ-lactam-δ-lactones bear angular quaternary benzylic stereocenters, which is noteworthy since the presence of a quaternary carbon in bioactive small molecules often promotes an element of conformational restriction that imparts potency, selectivity, and metabolic stability. The …


Emerging Technologies: Empowering People To Capture, Share And Transfer Tacit Knowledge, Donncadh J. Nagle, Melanie J. Adams Jun 2022

Emerging Technologies: Empowering People To Capture, Share And Transfer Tacit Knowledge, Donncadh J. Nagle, Melanie J. Adams

Level 3

ICH Q10 was published in 2008, and presented a model for an effective Pharmaceutical Quality System (PQS). However, the industry still has some way to go in embracing and implementing its principles in order to achieve greater product realisation, to establish and maintain a state of control, and to facilitate continual improvement.

ICH Q10 introduced us to two key enablers: Knowledge Management (KM) and Quality Risk Management (QRM).[1] While the pharmaceutical industry has made progress in implementing the principles of QRM since 2008, there has been significantly slower progress in implementing knowledge management practices. However, there may be solutions …


Steps Towards Digital Transformation In The Pharmaceutical Manufacturing Landscape Knowledge-Enabled Technology Transfer, Anne Greene Professor, Martin Lipa Dr Jun 2022

Steps Towards Digital Transformation In The Pharmaceutical Manufacturing Landscape Knowledge-Enabled Technology Transfer, Anne Greene Professor, Martin Lipa Dr

Level 3

No abstract provided.


Managing Risk And Knowledge: Frameworks To Guide Knowledge-Enabled Technology Transfer, Martin Lipa Dr, Anne Greene Jun 2022

Managing Risk And Knowledge: Frameworks To Guide Knowledge-Enabled Technology Transfer, Martin Lipa Dr, Anne Greene

Level 3

Technology transfer is not only about the transfer of technology, but also about the transfer of knowledge, as evidenced by definitions of KM within the biopharma industry and beyond. However, knowledge transfer is often not well structured and its effectiveness – in particular for tacit knowledge (i.e., know how) – is an opportunity for improvement which can lead to many benefits. This article profiles recent research into the topic of improving knowledge transfer during technology transfer and presents several recently developed frameworks for improving such. The article furthermore explains how the frameworks can be co-deployed in support of robust knowledge …


Tree Ring Isotopic Reconstruction Of Hurricane Dolores, Jonathan Kane Jun 2022

Tree Ring Isotopic Reconstruction Of Hurricane Dolores, Jonathan Kane

Earth and Planetary Sciences ETDs

Tree rings contain high-resolution climate proxies of temperature and precipitation (Hughes et al., 1982; Fritts 2012; Scuderi 1993). The objective of this study was to use tree ring cellulose, specifically measuring δ18O - the oxygen-18 to oxygen-16 stable isotope ratio- to investigate the impact of Hurricane Dolores, a tropical cyclone that produced heavy precipitation in the Sierra Nevada in July 2015. Prior studies (Berkelhammer and Stott, 2008, 2009) have shown that conifer forests in California record the influence of varying precipitation regimes in their ring alpha-cellulose. Hurricane Dolores produced an intense precipitation event that inundated parts of the Mojave Desert …


Differential Operators On Classical Invariant Rings Do Not Lift Modulo P, Jack Jeffries, Anurag K. Singh Jun 2022

Differential Operators On Classical Invariant Rings Do Not Lift Modulo P, Jack Jeffries, Anurag K. Singh

Department of Mathematics: Faculty Publications

Levasseur and Stafford described the rings of differential operators on various classical invariant rings of characteristic zero; in each of the cases that they considered, the differential operators form a simple ring. Towards an attack on the simplicity of rings of differential operators on invariant rings of linearly reductive groups over the complex numbers, Smith and Van den Bergh asked if differential operators on the corresponding rings of positive prime characteristic lift to characteristic zero differential operators. We prove that, in general, this is not the case for determinantal hypersurfaces, as well as for Pfaffian and symmetric determinantal hypersurfaces. We …


Preparation Of Carbon Aerogels From Polymer-Cross-Linked Xerogel Powders Without Supercritical Fluid Drying And Their Application In Highly Selective Co2adsorption, Rushi U. Soni, Vaibhav A. Edlabadkar, Daniel Greenan, Parwani M. Rewatkar, Nicholas Leventis, Chariklia Sotiriou-Leventis Jun 2022

Preparation Of Carbon Aerogels From Polymer-Cross-Linked Xerogel Powders Without Supercritical Fluid Drying And Their Application In Highly Selective Co2adsorption, Rushi U. Soni, Vaibhav A. Edlabadkar, Daniel Greenan, Parwani M. Rewatkar, Nicholas Leventis, Chariklia Sotiriou-Leventis

Chemistry Faculty Research & Creative Works

Carbon aerogels are well-known materials for their high porosity and high surface areas. They are typically made from pyrolysis of carbonizable polymeric aerogels. Here, we report an alternative route to monolithic carbon aerogels starting from xerogel powders. Use of powders speeds up solvent exchanges along sol-gel processing, and xerogelling bypasses the supercritical fluid drying step that is needed for making polymeric aerogels. Overall, this alternative route results in time, energy, and materials efficiency in the fabrication of carbon aerogels. Specifically, polymer-cross-linked silica xerogel powders were prepared via free-radical surface-initiated polymerization of acrylonitrile (AN) on a suspension of silica particles derived …


Calcium Bistriflimide-Mediated Sulfur(Vi)–Fluoride Exchange (Sufex): Mechanistic Insights Toward Instigating Catalysis, Brian Han, Samuel R. Khasnavis, Matthew Nwerem, Michael Bertagna, Nicholas D. Ball, O. Maduka Ogba Jun 2022

Calcium Bistriflimide-Mediated Sulfur(Vi)–Fluoride Exchange (Sufex): Mechanistic Insights Toward Instigating Catalysis, Brian Han, Samuel R. Khasnavis, Matthew Nwerem, Michael Bertagna, Nicholas D. Ball, O. Maduka Ogba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

We report a mechanistic investigation of calcium bistriflimide-mediated sulfur(VI)–fluoride exchange (SuFEx) between sulfonyl fluorides and amines. We determine the likely pre-activation resting state─a calcium bistriflimide complex with ligated amines─thus allowing for corroborated calculation of the SuFEx activation barrier at ∼21 kcal/mol, compared to 21.5 ± 0.14 kcal/mol derived via kinetics experiments. Transition state analysis revealed: (1) a two-point calcium-substrate contact that activates the sulfur(VI) center and stabilizes the leaving fluoride and (2) a 1,4-diazabicyclo[2.2.2]octane additive that provides Brønsted-base activation of the nucleophilic amine. Stable Ca–F complexes upon sulfonamide formation are likely contributors to inhibited catalytic turnover, and a proof-of-principle redesign …


Synthesis Of Phenyl Carbamoylated Guanidine Functionalized Chitosan, Eduardo Hernandez Requejo Jun 2022

Synthesis Of Phenyl Carbamoylated Guanidine Functionalized Chitosan, Eduardo Hernandez Requejo

FIU Electronic Theses and Dissertations

The lack of solubility of the chitosan in organic solvents hinders its potential for chemical modifications. For this reason, it was hypothesized that the insertion of the phenyl carbamoylated guanidine moiety could lead to increased solubility in DMSO and new potential modifications and uses.

This research involved the synthesis of S-methyl phenyl carbamoylated guanidine (SMPCG) starting from the commercially available S-methyl isothiourea. This was followed by the reaction of the SMPCG with chitosan to yield phenyl carbamoylated guanidine functionalized chitosan (PCGCs) with a degree of substitution of 14%.

The chitosan derivative is fully soluble in DMSO and partially in DMF. …


On Simultaneous Similarity Of D-Tuples Of Commuting Square Matrices, Corey Connelly Jun 2022

On Simultaneous Similarity Of D-Tuples Of Commuting Square Matrices, Corey Connelly

USF Tampa Graduate Theses and Dissertations

It has been shown by B. Shekhtman that when any d-tuple A of pairwise commuting N × N matrices with complex entries is cyclic, then A is simultaneously similar to the d-tuple of commuting N × N matrices B if and only if B is cyclic, and the sets of polynomials in d variables which annihilate A and B are equivalent.

This thesis offers a further generalization of this result, demonstrating the necessary and sufficient conditions for the simultaneous similarity of n-cyclic d-tuples of commuting square complex-valued matrices.