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Full-Text Articles in Physics

Studying Near-Critical And Super-Critical Fluids In Reduced Gravity, Christian Hawkins, Ana Oprisan, Carole Lecoutre-Chabot, Yves Garrabos, Daniel Beysens Aug 2019

Studying Near-Critical And Super-Critical Fluids In Reduced Gravity, Christian Hawkins, Ana Oprisan, Carole Lecoutre-Chabot, Yves Garrabos, Daniel Beysens

Journal of the South Carolina Academy of Science

Critical and supercritical fluids have a variety of applications, from use as machine lubricants in high pressure or high temperature environments to the manufacturing of materials such as aerogel. The optical properties of fluids undergo rapid changes near the critical point resulting in a rapid increase in turbidity known as critical opalescence. These optical changes can be used to probe the universality of critical behavior. As a fluid approaches the critical point, the compressibility rapidly increases. In a gravitational field, this increase in compressibility leads to near-critical fluids stratifying by phase and density, making it difficult to observe the optical ...


Table Of Contents Aug 2019

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Structure, Stability And Vibrational Properties Of Cdse Wurtzite Molecules And Nanocrystals: A Dft Study, Mudar A. Abdulsattar, Hayder M. Abduljalil, Hussein Hakim Abed Jul 2019

Structure, Stability And Vibrational Properties Of Cdse Wurtzite Molecules And Nanocrystals: A Dft Study, Mudar A. Abdulsattar, Hayder M. Abduljalil, Hussein Hakim Abed

Karbala International Journal of Modern Science

Bare and hydrogen passivated CdSe wurtzite molecules and nanostructures are investigated. The investigation is performed using wurtzoid structures that represent the wurtzite structure at the molecular and nanoscale region. The results show that the energy gap of bare and hydrogen passivated CdSe molecules is higher than and converges to the experimental bulk energy gap. Vibrational analysis of wurtzoid molecules shows that the experimental longitudinal optical mode is in between bare and hydrogen passivated CdSe molecules and very near to bare molecules. The stability of wurtzoid molecules against transition to CdSe diamondoids and cuboids that represent the molecular scale of diamond ...


A New Approach To The Potential Energy Of Solids, Radhika Chauhan, Sanjeev K. Verma, Anushri Gupta, Anita Kumari, B. D. Indu Jul 2019

A New Approach To The Potential Energy Of Solids, Radhika Chauhan, Sanjeev K. Verma, Anushri Gupta, Anita Kumari, B. D. Indu

Karbala International Journal of Modern Science

A general theory is developed to investigate the expression for potential energy without using (i) empirical results and (ii) process of parameterizing. The simple approach of thermodynamics is adopted to obtain the expressions for the interaction energy of solids in terms of interatomic separation and crystal volume. The new findings have been applied to obtain the expressions for bulk modulus and pressure. The variation of the potential energy function, which provides a means to understand the stability of a crystal has been found in excellent agreements to the earlier results. The use of obtained harmonic and anharmonic force constants may ...


Kinetic Study For The Effect Of New Inhibitors On The Activity Of Purified Gpt From Blood Of Cardiovascular Patients, Firas Maher Jul 2019

Kinetic Study For The Effect Of New Inhibitors On The Activity Of Purified Gpt From Blood Of Cardiovascular Patients, Firas Maher

Karbala International Journal of Modern Science

In this study several biochemical parameters for cardiovascular patients have been measured CK-MB ,LDH ,GPT and GOT in addition to lipid profile , MDA ,Vitamin C and Vitamin E . New derivatives of ascorbic acid have been synthesized and tested to inhibit the purified GPT from the blood of cardiovascular patients Glutamate pyruvate transaminase (GPT) was purified from cardiovascular patients using ammonium sulphate salt for precipitation then dialysed using 0.1 M Tris-HCL buffer pH7.8 , then filtrated by gel filtration chromatography using Sephadex G-100 , followed by electrophoresis using poly acrylamide – bis acrylamide and sodium dodecyl sulphate (SDS). Derivatives of 3-(acetyl ...


Neighborhoods And Partial Sums Of A New Class Of Meromorphic Multivalent Functions Defined By Fractional Calculus, Aqeel Ketab Al-Khafaji, Waggas Galib Atshan, Salwa Salman Abed Jul 2019

Neighborhoods And Partial Sums Of A New Class Of Meromorphic Multivalent Functions Defined By Fractional Calculus, Aqeel Ketab Al-Khafaji, Waggas Galib Atshan, Salwa Salman Abed

Karbala International Journal of Modern Science

In this paper, we introduce and study a new class A^* (λ,μ,ν,η,p,ζ,τ) of meromorphic multivalent functions defined by fractional calculus operator of the punctured unit disc U^*. On this class we obtain several results like, coefficient inequality, modified Hadamard product, (N,δ)- neighborhood, partial sums, convex linear combination and integral operator.


Biomedical Applications Of Chasmanthera Dependens Stem Extract Mediated Silver Nanoparticles As Antimicrobial, Antioxidant, Anticoagulant, Thrombolytic, And Larvicidal Agents, Daniel Ayandiran Aina, Oluwafayoke Owolo, Agbaje Lateef, Folasade O. Aina, Abbas Saeed Hakeem, Morenike Adeoye-Isijola, Victor Okon, Tesleem B. Asafa, Joseph Adetunji Elegbede, Olumide D. Olukanni, Isaac Adediji Jul 2019

Biomedical Applications Of Chasmanthera Dependens Stem Extract Mediated Silver Nanoparticles As Antimicrobial, Antioxidant, Anticoagulant, Thrombolytic, And Larvicidal Agents, Daniel Ayandiran Aina, Oluwafayoke Owolo, Agbaje Lateef, Folasade O. Aina, Abbas Saeed Hakeem, Morenike Adeoye-Isijola, Victor Okon, Tesleem B. Asafa, Joseph Adetunji Elegbede, Olumide D. Olukanni, Isaac Adediji

Karbala International Journal of Modern Science

The stem extract of Chasmanthera dependens was used in the biofabrication of silver nanoparticles (AgNPs) in this study. The AgNPs was characterised using UV-visible spectroscopy, Field Emission Scanning Electron Microscope (FESEM), EDX, and the Fourier Transform Infrared Spectroscopy (FTIR). Antibacterial, antioxidant, anticoagulant, thrombolytic and larvicidal activities of the biosynthesised nanoparticles were carried out. There was a peak at 418 nm with a strong silver peak observed around 2.7KeV when the EDX analysis was carried out. The FESEM showed a large number of cubically shaped nanoparticles with sizes ranging from 24.53 to 92.38 nm. CDE-AgNPs was effective against ...


Editorial Board Jul 2019

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.


60th Annual Rocky Mountain Conference On Magnetic Resonance Jul 2019

60th Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 60th annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Denver, Colorado, July 21-25, 2019.


A Brief Review Of Modern Uses Of Scattering Techniques, Daniel M. Wade, Dereth J. Drake Jun 2019

A Brief Review Of Modern Uses Of Scattering Techniques, Daniel M. Wade, Dereth J. Drake

Georgia Journal of Science

Thomson, Rayleigh, Mie, and Raman scattering are commonly used in several disciplines in science and engineering. The techniques involve the scattering of electromagnetic radiation or particles in a sample. This paper provides a brief history for each scattering method, describes the traditional laboratory approach for implementation, and discusses current uses and variations of these four techniques.


The Magnetic Activity Of Low-Mass Stars, Tholang Mota Jun 2019

The Magnetic Activity Of Low-Mass Stars, Tholang Mota

DePaul Discoveries

The purpose of this research project is to study magnetically active low mass stars using data obtained with the Kepler space telescope. A sample of low mass stars was identified in the Kepler Objects of Interest (KOI) database by selecting stars with a temperature below 3,700 K. Data was obtained from the Mikulski Archive for Space Telescopes and analyzed using the MATLAB software. Light curves showing the stellar flux vs time were generated for approximately 20 stars, and features showing stellar flares, star spots and planetary transits were identified. We found a weak relationship between magnetic activity and stellar ...


Pairwise Completely Positive Matrices And Conjugate Local Diagonal Unitary Invariant Quantum States, Nathaniel Johnston, Olivia Maclean May 2019

Pairwise Completely Positive Matrices And Conjugate Local Diagonal Unitary Invariant Quantum States, Nathaniel Johnston, Olivia Maclean

Electronic Journal of Linear Algebra

A generalization of the set of completely positive matrices called pairwise completely positive (PCP) matrices is introduced. These are pairs of matrices that share a joint decomposition so that one of them is necessarily positive semidefinite while the other one is necessarily entrywise non-negative. Basic properties of these matrix pairs are explored and several testable necessary and sufficient conditions are developed to help determine whether or not a pair is PCP. A connection with quantum entanglement is established by showing that determining whether or not a pair of matrices is pairwise completely positive is equivalent to determining whether or not ...


Haro 11, Pox 186, And Vcc 1313: The Enigmatic Behavior Of Hi Non-Emitters, Sarah H. Taft May 2019

Haro 11, Pox 186, And Vcc 1313: The Enigmatic Behavior Of Hi Non-Emitters, Sarah H. Taft

Macalester Journal of Physics and Astronomy

We present neutral hydrogen (HI) observations from the Very Large Array (VLA) telescope of the galaxies Haro 11, Pox 186, and VCC 1313. 24 hours of deep spectral line observation at the 21 cm line were obtained from the program 17B-287 of Haro 11, the primary galaxy studied in this capstone, and 176 and 203 respective minutes of archival VLA data at the 21 cm line were obtained from the program AS0832 of Pox 186 and VCC 1313, the secondary and tertiary sources of study for this capstone. Haro 11 is one of a very small number of local dwarf ...


Binary Neutron Star Merger Rates. Predictions From Observations Of Dwarf Galaxies And Observable Rates With Ground-Based Gravitational-Wave Detectors, Karen Perez Sarmiento May 2019

Binary Neutron Star Merger Rates. Predictions From Observations Of Dwarf Galaxies And Observable Rates With Ground-Based Gravitational-Wave Detectors, Karen Perez Sarmiento

Macalester Journal of Physics and Astronomy

Binary Neutron Star (BNS) mergers are interesting events in the field of multi-messenger astronomy since they are sources of detectable gravitational wave signals and electromagnetic transients. Here I introduce a new method to calculate a conservative, lower-limit for the rate of BNS merger events that is proportional to the stellar mass and is based on evidence of an r-process event in the dwarf galaxy Reticulum II. Two estimates of the stellar mass in the nearby universe were made using a Schechter Mass Function and a modified version of the 2MASS Extended Source Catalog (2MASS XSC). The BNS merger event rates ...


Uv Led System For Pl Measurements On Gan Samples, Dona H. Pantova May 2019

Uv Led System For Pl Measurements On Gan Samples, Dona H. Pantova

Macalester Journal of Physics and Astronomy

Gallium Nitride materials are direct bandgap semiconductors with important applications, such as in the production of light-emitting diodes and transistors. The process of photoluminescence, in which excited electron and holes emit electro-magnetic radiation when they recombine, can be used to study the structure and quality of Gallium Nitride materials. Due to the size of the bandgap in these materials (3.4eV), ultraviolet light is required to create electron-hole pairs in GaN. We designed and built a system, which uses ultraviolet light, to take measurements on GaN samples provided by a local company, Lightwave Photonics, who were interested in the quality ...


Investigation On The Electrical Properties Of Cdo/Zno Thin Films Using Thz Spectroscopy, Ramon Molina May 2019

Investigation On The Electrical Properties Of Cdo/Zno Thin Films Using Thz Spectroscopy, Ramon Molina

Macalester Journal of Physics and Astronomy

In this work, we study the electrical properties of transparent conducting oxides using physical and optical techniques. The objective is to characterize the conductivity of a series of cadmium oxide zinc-oxide thin films with varying cadmium concentrations using three methods. The Hall Effect estimates carrier concentration, sheet conductivity, and carrier mobility. Optical methods, such as FTIR spectroscopy, can provide estimates of the plasma frequency, which describes a metal’s transition from being transparent to opaque to light. THz spectroscopy extracts the complex conductivity of materials in the far infrared spectrum and provides insights on the optical transport properties of conductors ...


Understanding Solar Activity During The Last 400 Years, Sam Q. Hollenbach May 2019

Understanding Solar Activity During The Last 400 Years, Sam Q. Hollenbach

Macalester Journal of Physics and Astronomy

The solar cycle has a profound effect on both terrestrial and extra-terrestrial operations. Understanding the history of the solar cycle is necessary for studying long term trends, however older data is difficult to calibrate due to the sparsity of observations. In this paper we propose a new method for calibrating sunspot number data that does not rely on observational overlap. Initial testing shows promise in this method’s success, though more work must be done to ensure calibration consistency across all observers.


Recent Evolution Of The Eta Carinae Supernova Imposter System, Greta L. Helmel May 2019

Recent Evolution Of The Eta Carinae Supernova Imposter System, Greta L. Helmel

Macalester Journal of Physics and Astronomy

The supernova imposter Eta Carinae and its surrounding Homunculus reflection nebula have been of great interest for the last several decades. As the most massive star known in our Galaxy, this object is of particular importance in understanding high mass loss episodes and final stages in the evolution of other similarly massive stars in the later stages of their lives. Observations using the STIS CCD Instrument have been taken over the past 20 years for both the central star and the Homunculus as part of the Hubble Space Telescope (HST) Treasury Program on Eta Carinae. Recent changes in the spectra ...


The Neutral Hydrogen Kinematics Of The Dwarf Galaxy Merger Ngc 3239, Robert N. Ford May 2019

The Neutral Hydrogen Kinematics Of The Dwarf Galaxy Merger Ngc 3239, Robert N. Ford

Macalester Journal of Physics and Astronomy

We present H I spectral line images of the nearby dwarf galaxy NGC 3239. The galaxy’s curious morphology suggests that it is a post-merger system. We propose that NGC 3239 is a merger because it has multiple tidal tails, an enhanced velocity dispersion throughout the disk, and widespread star formation. We have produced kinematic moment maps corresponding to the H I column density, radial velocity, and velocity dispersion. Further, position velocity (P-V) slices of the galaxy were taken and three-color images were made using the SDSS G, R, and I, filters for comparison with the moment maps. These slices ...


Carrier Mobility Of Bismuth-Doped Perovskite, Kelly Flugaur-Leavitt May 2019

Carrier Mobility Of Bismuth-Doped Perovskite, Kelly Flugaur-Leavitt

Macalester Journal of Physics and Astronomy

As renewable energy increasingly becomes a priority around the world, the demand for inexpensive, efficient solar cells is greater than ever. Lead halide perovskites show promising potential, but have their share of drawbacks that could be improved through slight changes to its elemental composition. We used time-resolved terahertz spectroscopy to probe the differences created by doping lead halide perovskites with bismuth. We found that all samples, regardless of bismuth content, had a recombination time longer than one nanosecond, and that charge-carrier mobility decreased with the addition of bismuth.


Photometry Of Star Clusters From Mendel Observatory, James Biegel May 2019

Photometry Of Star Clusters From Mendel Observatory, James Biegel

Across the Bridge: The Merrimack Undergraduate Research Journal

We have observed four open star clusters and three globular star clusters using Mendel Observatory’s 18” Richey-Chrétien telescope. Our photometry data was obtained using nonstandard R, G, and B filters. We plotted the results in the form of a Hertzsprung-Russell (H-R) diagram in an attempt to determine the so called “turn-off point” for the observed clusters, which is a strong indicator of age. Due to our limited sample size of stars in each cluster, we were not able to determine the turn-off points and obtain relative ages for the clusters. However, we find that the shapes of our H-R ...


Computing Periods Of Nonlinear Hamiltonian Systems In The Two-Body Problem Of Celestial Mechanics, Maia Powell Apr 2019

Computing Periods Of Nonlinear Hamiltonian Systems In The Two-Body Problem Of Celestial Mechanics, Maia Powell

Ursidae: The Undergraduate Research Journal at the University of Northern Colorado

The two-body problem in celestial mechanics models the gravitational relationship between two celestial bodies and predicts their corresponding orbital paths. Isaac Newton proposed a two-body problem that accurately modeled systems whose rotating mass exhibited a perfectly elliptical orbit. Albert Einstein’s theory of general relativity expanded the original two-body problem to include systems with irregular orbits. Einstein’s model, a nonlinear Hamiltonian system, produces solutions that are elliptic functions. Though we know that elliptic solutions exist, their complexity makes them inaccessible. Current research explores potential properties of such irregular systems represented by Einstein’s model in an effort to better ...


Analytical Wave Solutions Of The Space Time Fractional Modified Regularized Long Wave Equation Involving The Conformable Fractional Derivative, M. Hafiz Uddin, Md. Ashrafuzzaman Khan, M. Ali Akbar, Md. Abdul Haque Mar 2019

Analytical Wave Solutions Of The Space Time Fractional Modified Regularized Long Wave Equation Involving The Conformable Fractional Derivative, M. Hafiz Uddin, Md. Ashrafuzzaman Khan, M. Ali Akbar, Md. Abdul Haque

Karbala International Journal of Modern Science

The space time fractional modified regularized long wave equation is a model equation to the gravitational water waves in the long-wave occupancy, shallow waters waves in coastal seas, the hydro-magnetic waves in cold plasma, the phonetic waves in dissident quartz and phonetic gravitational waves in contractible liquids. In nonlinear science and engineering, the mentioned equation is applied to analyze the one way tract of long waves in seas and harbors. In this study, the closed form traveling wave solutions to the above equation are evaluated due to conformable fractional derivatives through double (G'⁄G,1⁄G)-expansion method and the ...


Synthesis And Characterization Of Zro2: Mgo Thin Films By Plasma Of R.F. Magnetron Sputtering, Zainb Mohammed, Souad Khalil, Mahdi Mutter Mar 2019

Synthesis And Characterization Of Zro2: Mgo Thin Films By Plasma Of R.F. Magnetron Sputtering, Zainb Mohammed, Souad Khalil, Mahdi Mutter

Karbala International Journal of Modern Science

The aim of this work is to prepare thin composite films from zirconia (ZrO2) and magnesia (MgO) on to glass basis by plasma of R.F. magnetron sputtering as well as recognize their structural and optical properties. It also aims to study the effect of thermal processing at 450 °C in two hours duration. The structural properties are measured by X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The chemical analysis for the ready films had been studied using energy dispersive x-ray (EDX). The optical properties had been studied by using UV-Visible spectroscopy. Results show that ...


Analysis Of Dynamic Behaviour Of A Tensioned Carbon Nanotube In Thermal And Pressurized Environments, Ahmed Yinusa, Gbeminiyi Sobamowo Mar 2019

Analysis Of Dynamic Behaviour Of A Tensioned Carbon Nanotube In Thermal And Pressurized Environments, Ahmed Yinusa, Gbeminiyi Sobamowo

Karbala International Journal of Modern Science

In this paper, the dynamic behaviour of a tensioned single-walled carbon nanotubes (SWCNT) in thermal and pressurized environments is investigated analytically. With the applications of Bernoulli-Euler and thermal elasticity mechanics theories, the governing equation of motion are developed and solved using Laplace and Fourier transforms. The results of the close form solution in this work are in excellent agreements with past results in literature. From the parametric studies, it is established that as the magnitude of the pressure distribution at the surface increases, the deflection associated with the nanotube increases at any mode of vibration. However, a corresponding increase in ...


Editorial Board Mar 2019

Editorial Board

Karbala International Journal of Modern Science

No abstract provided.


Measurement Of Solar Spectral Irradiance And Surface Ozone At Carrollton, Georgia, Usa, During The Great American Eclipse On 21 August 2017, Kirthi Tennakone, L Ajith Desilva, Charles A. Zander*, Shea Rose, Austin B. Kerlin Mar 2019

Measurement Of Solar Spectral Irradiance And Surface Ozone At Carrollton, Georgia, Usa, During The Great American Eclipse On 21 August 2017, Kirthi Tennakone, L Ajith Desilva, Charles A. Zander*, Shea Rose, Austin B. Kerlin

Georgia Journal of Science

Measurements conducted at the University of West Georgia, Carrollton, Georgia, during the time of the solar eclipse of 21st August 2017 demonstrated that the integrated spectral irradiance in defined wavelength ranges in the ultraviolet and visible calculated as a fraction of the total irradiance reached a minimum at maximum obscuration of the Sun, whereas in an infrared range it was maximum. The method of analysis adopted supports the view that the changes in spectral irradiance during highly obscured partial phases is a consequence of limb darkening. In a surface ozone measurement, a minimum in ozone concentration occurred 30 +_ ...


Table Of Contents Mar 2019

Table Of Contents

Journal of the South Carolina Academy of Science

No abstract provided.


Comforting With Mathematics: A Case Study, Michael J. Goldstein Jan 2019

Comforting With Mathematics: A Case Study, Michael J. Goldstein

Journal of Humanistic Mathematics

Death by suicide often leaves behind grieving family members with unanswered questions. Of these concerns, fear that their loved one suffered or felt regret is common. When the method of suicide was jumping from height, that answer can easily be determined using basic kinematics. Despite the perception that mathematics is a cold, calculating field, it can provide a clear, definitive answer and comfort those left behind.


Comparisons Of Performance Between Quantum And Classical Machine Learning, Christopher Havenstein, Damarcus Thomas, Swami Chandrasekaran Jan 2019

Comparisons Of Performance Between Quantum And Classical Machine Learning, Christopher Havenstein, Damarcus Thomas, Swami Chandrasekaran

SMU Data Science Review

In this paper, we present a performance comparison of machine learning algorithms executed on traditional and quantum computers. Quantum computing has potential of achieving incredible results for certain types of problems, and we explore if it can be applied to machine learning. First, we identified quantum machine learning algorithms with reproducible code and had classical machine learning counterparts. Then, we found relevant data sets with which we tested the comparable quantum and classical machine learning algorithm's performance. We evaluated performance with algorithm execution time and accuracy. We found that quantum variational support vector machines in some cases had higher ...