Digital Commons Network^™

Hydro-Geochemistry And Related Processes Controlling The Composition Of Thermal Waters In The Lake Natron Basin, Northern Tanzania, Edista A. Abdallah, Charles H. Kasanzu, Crispin P. Kinabo, Akira Imai

Tanzania Journal of Science

Lake Natron Basin (LNB) forms part of the eastern branch of the East African Rift System (EARS) in Tanzania. The basin is endowed with thermal springs flowing towards the lake from the western, northwestern, southwestern and eastern parts. The western, northwestern and south-western thermal springs emanate from fractures in the basaltic rocks while in the east, they originate from the western flank of the Gelai volcano. There are limited studies on these springs, thus their geochemical differences and distributions of physicochemical parameters are not well understood. A hydrogeochemical study was conducted to interpret available geochemical data from the LNB springs, …

Optical Characterization Of Photocatalytic Tungsten Oxide/Tin Oxide (〖Wo〗_3/〖Sno〗_2) Thin Films For Use In Degradation Of Water Pollutants, Victor Isahi, Christopher Maghanga, Mghendi Mwamburi, Onesmus Munyati, Sylvester Hatwaambo, Emmanuel Akoto, Wycliffe Isoe, Mir Waqas Alam

Tanzania Journal of Science

Organic pollutants in water have been a challenge and pose significant risks to human health. As a result, research efforts to eliminate these pollutants have been on the rise. Photocatalysis has shown incredible potential in water treatment containing organic pollutants since it is affordable and utilizes solar energy. Tin oxide ( ) has ardently been investigated as a photocatalyst for water treatment due to its remarkable properties such as; non-toxicity, and stability. However, its wide band gap and the tendency for some electrons and holes to recombine during its use have been cited to be among limiting factors affecting its …

Experimental Measurements Of Ignition Delay Times Of Iso-Octane/N-Butanol Blend Mixtures In Rapid Compression Machine (Rcm), Myeji Materego, Derek Bradley

Tanzania Journal of Science

Among oxygenated alternative fuels, n-butanol is considered as a promising alternative biofuel which can partially (or fully) replace conventional transportation fuels currently in use. However, before n-butanol can be commercially utilised, its fundamental combustion characteristics need to be fully understood. In this work, the effect of adding n-butanol on autoignition property of iso-octane was studied. Measurements of ignition delay times for the two blends of n-butanol proportions of 30% and 50% by mole weight were made in a Rapid Compression Machine for stoichiometric mixtures at 2.0 MPa and temperature range 651-918 K. n-butanol increased ignition delay times of iso-octane at …

Thermal Dose Inactivation Of Escherichia Coli By Magnetic Induced Hyperthermia, Silverio A. Lopez, Carlos Trevino De Leo, Ivan Davila, Karen S. Martirosyan

Research Symposium

Background: Apoptosis of mutated cells via magnetic hyperthermia has gained advocacy as technology capable of being used in lieu of chemotherapy for targeting cancer tumors. Progress of nanotechnology offers effective remote heating of magnetic fluid via hyperthermia. The heating and specific power absorption of these nanoparticles use in the magnetic fluid are dependent on particle properties and treatment locations.

Methods: Nanoparticles were fabricated using microfluidic system by interaction of two solutions containing 2Fe(NO3)3+FeSO4 and NaOH+2%Dextran to create nanostructured media with a biocompatible dextran coating and a Fe3O4 core. The nanoparticles, of a concentration of 5mg/ml, were placed in a vile …

Angular Dependence Of The Magnetization Relaxation In Co/Pt Multilayers, Anil Adhikari, Bryce Herrington, Nhat Nguyen, Ruthi Zielinski, Ather Mahmood, S. Adenwalla, Robert Streubel

Department of Physics and Astronomy: Faculty Publications

We study the influence of defects in Co/Pt multilayers on the room-temperature magnetization reversal and relaxation mechanisms via angle-dependent magnetic viscosity and coercive field measurements. The data reveal a transition from pinning-dominated domain wall propagation to a sequence of pinning-dominated and uniform switching, with increasing tilt away from the normal direction. The leading role of the dendritic domain wall propagation in the nanogranular exchange-coupled films is corroborated by the scaling of relaxation times, the angular dependence of the coercive field, and Kerr microscopy.

The Role Of Nanofluids In Renewable Energy Engineering, M. M. Bhatti, K. Vafai, Sara I. Abdelsalam

Basic Science Engineering

No abstract provided.

An Ngqd Based Diagnostic Tool For Pancreatic Cancer, Ryan Ketan Ajgaonkar, Bong Lee, Alina Valimukhametova, Anton Naumov, Giridhar Akkaraju

Research Symposium

Background: Pancreatic cancer remains difficult to detect at early stages which contributes to a poor five-yearsurvival rate. Therefore, early detection approaches based on novel technologies should be explored to address this critical health issue. Nanomaterials have recently emerged as frontrunners for diagnostic applications due to their small size in the 1-100 nm range, which facilitates one-on-one interactions with a variety of biomolecules like oligonucleotides and makes them suitable for a plethora of detection and delivery applications. In this work, the presence of specific pancreatic cancer miRNA (pre-miR-132) is detected utilizing the fluorescence properties of highly biocompatible nitrogen-doped graphene quantum dots …

Search For Gravitational Waves Associated With Fast Radio Bursts Detected By Chime/Frb During The Ligo–Virgo Observing Run O3a, R. Abbott, T. Abbott, F. Acernese, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

We search for gravitational-wave (GW) transients associated with fast radio bursts (FRBs) detected by the Canadian Hydrogen Intensity Mapping Experiment Fast Radio Burst Project, during the first part of the third observing run of Advanced LIGO and Advanced Virgo (2019 April 1 15:00 UTC–2019 October 1 15:00 UTC). Triggers from 22 FRBs were analyzed with a search that targets both binary neutron star (BNS) and neutron star–black hole (NSBH) mergers. A targeted search for generic GW transients was conducted on 40 FRBs. We find no significant evidence for a GW association in either search. Given the large uncertainties in the …

Effects Of Spin-Orbit Coupling On Gravitational Waveforms From A Triaxial Nonaligned Neutron Star In A Binary System, Wen-Fan Feng, Tan Liu, Jie-Wen Che, Yan Wang, Soumya D. Mohanty

Physics & Astronomy Faculty Publications

Spinning neutron stars (NSs) can emit continuous gravitational waves (GWs) that carry a wealth of information about the compact object. If such a signal is detected, it will provide us with new insight into the physical properties of matter under extreme conditions. According to binary population synthesis simulations, future space-based GW detectors, such as LISA and TianQin, can potentially detect some double NSs in tight binaries with orbital periods shorter than 10 minutes. The possibility of a successful directed search for continuous GWs from the spinning NS in such a binary system identified by LISA/TianQin will be significantly increased with …

Non-Hermitian Gauged Laser Arrays With Localized Excitations: Anomalous Threshold And Generalized Principle Of Selective Pumping, Li Ge, Zihe Gao, Liang Feng

Publications and Research

We investigate non-Hermitian skin modes in laser arrays with spatially localized excitation. Intriguingly, we observe an unusual threshold behavior when selectively pumping either the head or the tail of these modes: both cases exhibit the same lasing threshold and hence defy the conventional principle of selective pumping, which aims to maximize the overlap between the pump profile and the target lasing mode. To shed light on this enigma, we reveal a previously overlooked phenomenon, i.e., energy exchange at non-Hermitian coupling junctions with the photonic environment, which does not occur with uniform gain or loss. Utilizing a transfer matrix approach, we …

Why Interference Phenomena Do Not Capture The Essence Of Quantum Theory, Lorenzo Catani, Matthew Leifer, David Schmid, Robert W. Spekkens

Mathematics, Physics, and Computer Science Faculty Articles and Research

Quantum interference phenomena are widely viewed as posing a challenge to the classical worldview. Feynman even went so far as to proclaim that they are the only mystery and the basic peculiarity of quantum mechanics. Many have also argued that basic interference phenomena force us to accept a number of radical interpretational conclusions, including: that a photon is neither a particle nor a wave but rather a Jekyll-and-Hyde sort of entity that toggles between the two possibilities, that reality is observerdependent, and that systems either do not have properties prior to measurements or else have properties that are subject to …

K-Long Identification Efficiency Of The Klm Detector In The Belle Ii Experiment Using Splot, Andrew J. Davis, Diptaparna Biswas, Swagato Banerjee

The Cardinal Edge

Long-lived neutral kaon mesons (neutral K-longs) are identified by energy deposits in the KLM detector of the Belle II experiment. However, various other particles can also deposit energy in the KLM detector. A statistical method known as sPlot can be utilized to distinguish between the energy deposit patterns of neutral K-longs vs. other backgrounds. This technique, currently developed with Monte-Carlo events, allows for a more robust determination of K-long identification efficiency in the KLM detector, which can eventually be applied on real data.

Tunneling Time And Faraday/Kerr Effects In Pt-Symmetric Systems, Peng Guo, Vladimir Gasparian, Antonio Antonio Perez-Garrido, Ester Jodar Ferrandez

Research & Publications

We review the generalization of tunneling time and anomalous behaviour of Fara- day and Kerr rotation angles in parity and time (PT )-symmetric systems. Similarities of two phenomena are discussed, both exhibit a phase transition-like anomalous behaviour in a certain range of model parameters. Anomalous behaviour of tunneling time and Faraday/Kerr angles in PT -symmetric systems is caused by the motion of poles of scattering amplitudes in the en- ergy/frequency complex plane.

Superoscillations And Fock Spaces, Daniel Alpay, Fabrizio Colombo, Kamal Diki, Irene Sabadini, Daniele C. Struppa

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this paper we use techniques in Fock spaces theory and compute how the Segal-Bargmann transform acts on special wave functions obtained by multiplying superoscillating sequences with normalized Hermite functions. It turns out that these special wave functions can be constructed also by computing the approximating sequence of the normalized Hermite functions. First, we start by treating the case when a superoscillating sequence is multiplied by the Gaussian function. Then, we extend these calculations to the case of normalized Hermite functions leading to interesting relations with Weyl operators. In particular, we show that the Segal-Bargmann transform maps superoscillating sequences onto …

Modified Newtonian Dynamics As An Alternative To The Planet Nine Hypothesis, Harsh Mathur

Faculty Scholarship

A new class of Kuiper Belt objects (KBOs) that lie beyond Neptune with semimajor axes greater than 250 astronomical units show orbital anomalies that have been interpreted as evidence for an undiscovered ninth planet. We show that a modified gravity theory known as modified Newtonian dynamics (MOND) provides an alternative explanation for the anomalies using the well-established secular approximation. We predict that the major axes of the orbits will be aligned with the direction toward the Galactic center and that the orbits cluster in phase space, in agreement with observations of KBOs from the new class. Thus, MOND, which can …

Eggshell-Alginate Composites (Eacs) As Eco-Friendly Adsorbents For Rhodamine B Uptake From Aqueous Solutions, Rusnadi Rusnadi, Mar’Atus Sholihah, Nurrahmi Handayani, Muhammad Ali Zulfikar

Karbala International Journal of Modern Science

The contamination of wastewater by Rhodamine B (RhB) poses a significant environmental concern due to its negative impacts on aesthetics, ecosystems, and human well-being. This study successfully synthesized eco-friendly egg-shell-alginate composites (EACs) as adsorbents by combining alginate solution, eggshell powder, and a 2% CaCl2 solu-tion. Characterization techniques including FTIR, SEM, TGA, and SAA were employed to analyze the EACs. FTIR analysis revealed characteristic absorption peaks corresponding to -OH groups, C=O groups, C-O groups, and the pres-ence of CO32-. The structural analysis confirmed the physical mixture of functional groups from eggshells and alginate, resulting in a homogeneous EACs mixture. TGA analysis …

Synthesizing Of Alginate Coated-Silver Nanoparticles Core-Shell For Detecting Of S-Naproxen Enantiomer In Pharmaceutical Formulation, Abdolrasol Barazandeh, Ghasem Najafpour-Darz, Afshar Alihossein, Sohrab Kazemi

Karbala International Journal of Modern Science

Core-shell nanoparticles were used in a unique direct UV-Vis spectrophotometric technique to detect the S-naproxen enantiomer. Silver nanoparticles (Ag NPs) covered with sodium alginate (Alg) shell, a naturally occurring biopolymer, made the core of the nanostructure. To name a few, TEM, FESEM, UV-Visible, DLS, ZP, AFM, XRD, EDX and FT-IR are among the analytical methods used to analyze the creation of the core-shell structure. Based on obtained results, spherical Ag@ Alg NPs with an average size of 27.4 nm (DTEM), hydrolytic size of 46 nm (DDLS) and surface charge of -60.9 mV were successfully synthesized. The effect of various reaction …

Improving The Structural And Physical Yield Of Aluminum By Repeated Additions Of Iron Carbide, Fayrooz K. Albasri

Al-Bahir

Aluminum suffers from low hardness and some ductility when thermal sintering which requires reinforcement with carbide or ceramic materials as Iron FeC with volumetric properties (2,4,6,8,10 )%. For purpose of the pressing process after mixing the two powder together, a scanning electron microscope examination performed for the prepared samples and found that there is a surface and structural consistency between aluminum and iron carbide and the best homogeneity is at10 % of carbide. Also some physical tests conducted for prepared samples and the results of the real density showed that the addition of iron carbide increases the density gradually and …

Anharmonic Ir Absorption Spectra Of The Prototypical Interstellar Pahs Phenanthrene, Pyrene, And Pentacene In Their Neutral And Cation States, Vincent J. Esposito, Louis J. Allamandola, Christiaan Boersma, Jesse D. Bregman, Ryan C. Fortenberry, Alexandros Maragkoudakis, Pasquale Temi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Combination band and overtone transitions of polycyclic aromatic hydrocarbon (PAH) cations in the 2000–2900 cm^-1 (5-3.5 µm) region are implicated as carriers of the ‘quasi-continuum’ observed in the near-infrared (IR) emission spectra of many astronomical objects. In neutral PAHs, the strongest absorption features are concentrated in the 700–900 cm^-1 (14–11 µm) range, which are associated with CH out-of-plane bending motions. Upon ionization, this shifts to the 1000–1600 cm^-1 (10–6 µm) range, where bands are associated with C=C stretches and CH in-plane bends. Anharmonicity is required to accurately characterize the IR absorption spectrum of PAHs, indicated herein by …

Measurement Of The Dependence Of The Hadron Production Fraction Ratios F S/F U And F D/F U On B Meson Kinematic Variables In Proton-Proton Collisions At √S=13 Tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

The dependence of the ratio between the B⁰_s and B⁺ hadron production fractions, f_s/f_u, on the transverse momentum (p_T) and rapidity of the B mesons is studied using the decay channels B⁰_s → J/ψϕ and B⁺ → J/ψK⁺. The analysis uses a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment in 2018 and corresponding to an integrated luminosity of 61.6 fb⁻¹. The f_s/f_u ratio is observed to depend on the B …

Mass-Selected Ion–Molecule Cluster Beam Apparatus For Ultrafast Photofragmentation Studies, Xiaojun Wang, Mahmudul Hasan, Lin Fan, Yibo Wang, Hui Li, Daniel S. Slaughter, Martin Centurion

Department of Physics and Astronomy: Faculty Publications

We describe an apparatus for investigating the excited-state dissociation dynamics of mass-selected ion–molecule clusters by mass-resolving and detecting photofragment-ions and neutrals, in coincidence, using an ultrafast laser operating at high repetition rates. The apparatus comprises a source that generates ion–molecule clusters, a time-of-flight spectrometer, and a mass filter that selects the desired anions, and a linear-plus-quadratic reflectron mass spectrometer that discriminates the fragment anions after the femtosecond laser excites the clusters. The fragment neutrals and anions are then captured by two channeltron detectors. The apparatus performance is tested by measuring the photofragments: I⁻, CF₃I⁻, …

Precision E- Beam Polarimetry At An E-E+ B Factory Using Tau-Pair Events, J. P. Lees, V. Poireau, V, Tisserand, E. Grauges, A. Palano, G. Eigen, D. N. Brown, Yu. G. Kolomensky, M. Fritsch, H. Koch, R. Cheaib, C. Hearty, T. S. Mattison, J. A. Mckenna, R. Y. So, V. E. Blinov, A. R. Buzykaev, V. P. Druzhinin, Milind Purohit, Et. Al.

Faculty Publications

We present a new technique, “tau polarimetry,” for measuring the longitudinal beam polarization present in an e⁺e⁻ collider through the analysis of e⁺e⁻ → τ⁺τ⁻ events. By exploiting the sensitivity of τ decay kinematics to the longitudinal polarization of the beams, we demonstrate that the longitudinal polarization can be measured with a 3 per mil systematic uncertainty at the interaction point using a technique that is independent of spin and beam transport modeling. Using 424.2 ± 1.8 fb⁻¹ of BABAR data at √ s = 10.58 GeV, the average longitudinal …

Measurement Of The Top Quark Mass Using A Profile Likelihood Approach With The Lepton + Jets Final States In Proton–Proton Collisions At √ S = 13tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

The mass of the top quark is measured in 36.3 fb⁻¹ of LHC proton–proton collision data collected with the CMS detector at √ s = 13 TeV. The measurement uses a sample of top quark pair candidate events containing one isolated electron or muon and at least four jets in the final state. For each event, the mass is reconstructed from a kinematic fit of the decay products to a top quark pair hypothesis. A profile likelihood method is applied using up to four observables per event to extract the top quark mass. The top quark mass is measured …

Measurement Of The Top Quark Mass Using A Profile Likelihood Approach With The Lepton + Jets Final States In Proton–Proton Collisions At √S = 13tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

The mass of the top quark is measured in 36.3 fb⁻¹ of LHC proton–proton collision data collected with the CMS detector at √ s = 13 TeV. The measurement uses a sample of top quark pair candidate events containing one isolated electron or muon and at least four jets in the final state. For each event, the mass is reconstructed from a kinematic fit of the decay products to a top quark pair hypothesis. A profile likelihood method is applied using up to four observables per event to extract the top quark mass. The top quark mass is measured …

Trumpet Directivity From A Rotating Semicircular Array, Samuel D. Bellows, Joseph E. Avila, Timothy W. Leishman

Directivity

The directivity function of a played musical instrument describes the angular dependence of its acoustic radiation and diffraction about the instrument, musician, and musician’s chair. Directivity influences sound in rehearsal, performance, and recording environments and signals in audio systems. Because high-resolution, spherically comprehensive measurements of played musical instruments have been unavailable in the past, the authors have undertaken research to produce and share such data for studies of musical instruments, simulations of acoustical environments, optimizations of microphone placements, and other applications. The authors acquired the data from repeated chromatic scales produced by a trumpet played at mezzo-forte in an anechoic …

Constraining Subtleties Of General Relativity And Quantum Phenomena Of Gravitational Radiation With Gravitational-Wave Observations, Matthew Fowler Carney

Arts & Sciences Graduate Student Theses and Dissertations

Initial observations of gravitational-waves (GW) from the mergers of compact binaries have further solidified GR as an accurate model of gravity on large scales, as well as provided novel insight into the populations of the compact objects from which they originate. Next-generation detectors such as LISA, Einstein Telescope, and Cosmic Explorer are slated for operation in the next few decades and will bring with them vastly improved sensitivities and orders of magnitude more GW events. It is therefore imperative that model development and characterization of secondary effect---either smaller in magnitude in than current noise levels or too infrequent at current …

Microplastics In Water, Their Effects On The Aquatic Ecosystem And Human Public Health, And The Proposed Solutions, Mohanad Abouserie

The Undergraduate Research Journal

We could be swallowing a credit card's weight in plastic every week. Microplastic water pollution is becoming a threat to both humans and aquatic creatures. In this research, microplastic water contamination is discussed, and divergent solutions are proposed. This paper attempts to investigate the causes and effects of such pollution and analyze the current solutions for this issue. The adopted research method is secondary research, where several studies are explored and analyzed. This study explains numerous causes for this issue like cosmetics, cleaning products, factories, and sewage. Consequently, this contamination can negatively impact the organs and metabolisms of the living …

Energy Extraction From Black Holes By Cosmic Strings, Michael Ramsey

Discovery Day

Cosmic strings, speculative one-dimensional objects, are thought to result from spontaneous, electroweak symmetry-breaking phase transitions in the early universe. If cosmic strings exist, they could extract energy from spinning black holes via the Penrose process. Although theoretically motivated, cosmic strings have not yet been observed. We propose an indirect method of observing a cosmic string by investigating a pulsar-black hole binary system, using high precision observations of pulsars. We then aim to place bounds on cosmic string abundance and tension.

The Role Of Leading-Edge Serrations In Controlling The Flow Over Owls’ Wing, Tanner Saussaman, Asif Nafi, David Charland, Hadar Ben-Gida, Roi Gurka

Physics and Engineering Science

We studied the effects of leading-edge serrations on the flow dynamics developed over an owl wing model. Owls are predatory birds. Most owl species are nocturnal, with some active during the day. The nocturnal ones feature stealth capabilities that are partially attributed to their wing microfeatures. One of these microfeatures is small rigid combs (i.e. serrations) aligned at an angle with respect to the incoming flow located at the wings' leading-edge region of the primaries. These serrations are essentially passive flow control devices that enhance some of the owls' flight characteristics, such as aeroacoustics and, potentially, aerodynamics. We performed a …

Large Anomalous Hall, Nernst Effect And Topological Phases In The 3d-4d/5d Based Oxide Double Perovskites, Kartik Samanta, Jonathan Noky, Iñigo Robredo, Juergen Kuebler, Maia G. Vergniory, Claudia Felser

Department of Physics and Astronomy: Faculty Publications

Magnetism and spin-orbit coupling are two fundamental and interconnected properties of oxide materials, that can give rise to various topological transport phenomena, including anomalous Hall and anomalous Nernst effects. These transport responses can be significantly enhanced by designing an electronic structure with a large Berry curvature. In this context, rocksalt-ordered double perovskites (DP), denoted as A₂BB’O₆, with two distinct transition metal sites are very powerful platforms for exploration and research. In this work, we present a comprehensive study based on the intrinsic anomalous transport in cubic and tetragonal stable DP compounds with 3d-4d/5d elements. Our findings …