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Articles 24871 - 24900 of 294699

Full-Text Articles in Physical Sciences and Mathematics

Soft Sets Extensions: Innovating Healthcare Claims Analysis, Daniela Gifu, Florentin Smarandache Aug 2024

Soft Sets Extensions: Innovating Healthcare Claims Analysis, Daniela Gifu, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In the dynamic arena of healthcare research, where the complexities of data often rival the intricacies of biological systems, the ability to model and analyze such multifaceted datasets is crucial. This comprehensive review delves into the evolution and application of Soft Sets and their extensions, including HyperSoft Sets, SuperHyperSoft Sets, IndetermSoft Sets, IndetermHyperSoft Sets, and TreeSoft Sets, in healthcare claims data analysis.

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Ultralight Vector Dark Matter Search Using Data From The Kagra O3gk Run, A. Abac, R. Abbott, H. Abe, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang Aug 2024

Ultralight Vector Dark Matter Search Using Data From The Kagra O3gk Run, A. Abac, R. Abbott, H. Abe, Teviet Creighton, Mario C. Diaz, Francisco Llamas, Soma Mukherjee, Gaukhar Nurbek, Volker Quetschke, Wenhui Wang

Physics & Astronomy Faculty Publications

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the …

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Open-Loop Wavefront Sensing In The Presence Of Speckle And Weak Scintillation, Derek J. Burrell, Mark F. Spencer, Ronald G. Driggers Aug 2024

Open-Loop Wavefront Sensing In The Presence Of Speckle And Weak Scintillation, Derek J. Burrell, Mark F. Spencer, Ronald G. Driggers

Faculty Publications

In this paper, we show that speckle averaging helps to reduce the measurement error associated with a Shack–Hartmann wavefront sensor (SHWFS); however, this reduction is rendered ineffective with increasing beacon anisoplanatism. We do so operating in a weak-scintillation regime, where the SHWFS offers robust performance, and using in-plane translation of the illuminated rough surface to accomplish frame-to-frame speckle diversity. Understanding these trade-space limitations is critical when performing wavefront sensing with noncooperative, extended-source beacons.

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An Online Nanoinformatics Platform Empowering Computational Modeling Of Nanomaterials By Nanostructure Annotations And Machine Learning Toolkits., Tong Wang, Daniel P Russo, Philip Demokritou, Xuelian Jia, Heng Huang, Xinyu Yang, Hao Zhu Aug 2024

An Online Nanoinformatics Platform Empowering Computational Modeling Of Nanomaterials By Nanostructure Annotations And Machine Learning Toolkits., Tong Wang, Daniel P Russo, Philip Demokritou, Xuelian Jia, Heng Huang, Xinyu Yang, Hao Zhu

College of Science & Mathematics Departmental Research

Modern nanotechnology has generated numerous datasets from in vitro and in vivo studies on nanomaterials, with some available on nanoinformatics portals. However, these existing databases lack the digital data and tools suitable for machine learning studies. Here, we report a nanoinformatics platform that accurately annotates nanostructures into machine-readable data files and provides modeling toolkits. This platform, accessible to the public at https://vinas-toolbox.com/, has annotated nanostructures of 14 material types. The associated nanodescriptor data and assay test results are appropriate for modeling purposes. The modeling toolkits enable data standardization, data visualization, and machine learning model development to predict properties and bioactivities …

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Mhongoose: A Meerkat Nearby Galaxy H I Survey, Stacy S. Mcgaugh Aug 2024

Mhongoose: A Meerkat Nearby Galaxy H I Survey, Stacy S. Mcgaugh

Faculty Scholarship

The MHONGOOSE (MeerKAT H i Observations of Nearby Galactic Objects: Observing Southern Emitters) survey maps the distribution and kinematics of the neutral atomic hydrogen (H i) gas in and around 30 nearby star-forming spiral and dwarf galaxies to extremely low H i column densities. The H i column density sensitivity (3σ over 16 km s−1) ranges from ∼5 × 1017 cm−2 at 9000 resolution to ∼4 × 1019 cm−2 at the highest resolution of 700. The H i mass sensitivity (3σ over 50 km s−1) is ∼5.5×105 M at a distance of 10 Mpc (the median distance of the sample …

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The Ultraviolet Luminosity Function At 0.6 < Z < 1 From Uvcandels, Lei Sun, Xin Wang, Harry I. Teplitz, Vihang Mehta, Anahita Alavi, Marc Rafelski, Rogier A. Windhorst, Claudia Scarlata, Jonathan P. Gardner, Brent M. Smith, Ben Sunnquist, Laura Prichard, Yingjie Cheng, Norman Grogin, Nimish P. Hathi, Matthew Hayes, Anton M. Koekemoer, Bahram Mobasher, Kalina V. Nedkova, Robert O’Connell, Brant Robertson Aug 2024

The Ultraviolet Luminosity Function At 0.6 < Z < 1 From Uvcandels, Lei Sun, Xin Wang, Harry I. Teplitz, Vihang Mehta, Anahita Alavi, Marc Rafelski, Rogier A. Windhorst, Claudia Scarlata, Jonathan P. Gardner, Brent M. Smith, Ben Sunnquist, Laura Prichard, Yingjie Cheng, Norman Grogin, Nimish P. Hathi, Matthew Hayes, Anton M. Koekemoer, Bahram Mobasher, Kalina V. Nedkova, Robert O’Connell, Brant Robertson

Pacific Faculty Work

UVCANDELS is a Hubble Space Telescope Cycle-26 Treasury Program awarded 164 orbits of primary ultraviolet (UV) F275W imaging and coordinated parallel optical F435W imaging in four CANDELS fields—GOODS-N, GOODS-S, EGS, and COSMOS—covering a total area of ∼426 arcmin2. This is ∼2.7 times larger than the area covered by previous deep-field space UV data combined, reaching a depth of about 27 and 28 ABmag (5σ in 0.”2 apertures) for F275W and F435W, respectively. Along with new photometric catalogs, we present an analysis of the rest-frame UV luminosity function (LF), relying on our UV-optimized aperture photometry method, yielding a factor …

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Application Of A Novel Plasma-Based Advanced Oxidation Process For Efficient And Cost-Effective Destruction Of Refractory Organics In Tertiary Effluents And Contaminated Groundwater, Itay Even-Ezra, Anat Mizrahi, Daniel Gerrity, Shane A. Snyder, Andrew Salveson, Ori Lahav Aug 2024

Application Of A Novel Plasma-Based Advanced Oxidation Process For Efficient And Cost-Effective Destruction Of Refractory Organics In Tertiary Effluents And Contaminated Groundwater, Itay Even-Ezra, Anat Mizrahi, Daniel Gerrity, Shane A. Snyder, Andrew Salveson, Ori Lahav

Civil and Environmental Engineering and Construction Faculty Research

Corona discharge is emerging as a promising advanced oxidation process (AOP) for the treatment of a variety of organic contaminants, including compounds that are not effectively destroyed by more common AOPs. This paper presents laboratory and field results describing the destruction of regulated and Contaminant Candidate List (CCL) compounds in tertiary treated wastewater effluent and contaminated groundwater during the operation of a novel hydro-non-thermal-plasma (HNTP) AOP system. The system generates a plasma discharge above the target water matrix, which emits an “electron wind”, ultraviolet (UV) irradiation, O3(g) and hydroxyl radicals (•OH) into a relatively thin water layer. The synergism …

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The Bicomplex Tensor Product And A Bicomplex Choi Theorem, Daniel Alpay, Antonino De Martino, Kamal Diki, Mihaela Vajiac Aug 2024

The Bicomplex Tensor Product And A Bicomplex Choi Theorem, Daniel Alpay, Antonino De Martino, Kamal Diki, Mihaela Vajiac

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this paper we extend the concept of tensor product to the bicomplex case and use it to prove the bicomplex counterpart of the classical Choi theorem in the theory of complex matrices and operators. The concept of hyperbolic tensor product is also discussed, and we link these results to the theory of quantum channels in the bicomplex and hyperbolic case.

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Quantum Field Theory And The Limits Of Reductionism, Emily Adlam Aug 2024

Quantum Field Theory And The Limits Of Reductionism, Emily Adlam

Mathematics, Physics, and Computer Science Faculty Articles and Research

I suggest that the current situation in quantum field theory (QFT) provides some reason to question the universal validity of ontological reductionism. I argue that the renormalization group flow is reversible except at fixed points, which makes the relation between large and small distance scales quite symmetric in QFT, opening up at least the technical possibility of a non-reductionist approach to QFT. I suggest that some conceptual problems encountered within QFT may potentially be mitigated by moving to an alternative picture in which it is no longer the case that the large supervenes on the small. Finally, I explore some …

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Molecular Docking, Pharmacological Profiling, And Molecular Dynamics Simulation Of Potential Antihyperuricemic Agent From Secondary Metabolites Of Dillenia Philippinensis Rolfe (Dilleniaceae), Louie Rince C. Suyo, John P. Paulin, Nicole Clarence Louise L. Gapaz, Markus Brent S. Arevalo, Vince Tyrell P. Yongco, Librado A. Santiago Aug 2024

Molecular Docking, Pharmacological Profiling, And Molecular Dynamics Simulation Of Potential Antihyperuricemic Agent From Secondary Metabolites Of Dillenia Philippinensis Rolfe (Dilleniaceae), Louie Rince C. Suyo, John P. Paulin, Nicole Clarence Louise L. Gapaz, Markus Brent S. Arevalo, Vince Tyrell P. Yongco, Librado A. Santiago

Karbala International Journal of Modern Science

Crystal accumulation in the joints due to increased serum uric acid (sUA) may lead to an inflammatory condition called gout. Increased sUA is caused by the excessive reabsorption of the urate anion transporter-1 (URAT-1). Therefore, URAT-1 inhibition will promote uric acid excretion and reduce the risk of having gout. Dillenia philippinensis Rolfe, often known as katmon, is an endemic plant in the Philippines with bioactive compounds associated with several therapeutic benefits. The present study represents the first scientific inquiry into the antihyperuricemic potential of compounds isolated from D. philippinensis. This study aimed to assess the interaction of URAT-1 with …

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Preparation Of A Chiral Hyperbranched Polymer Based On Cinchona Alkaloids And Investigation Of Its Catalytic Activity In Asymmetric Reactions, Rafiqul Islam, Mohammad Shahid Ullah, Abdus Salam, Shinichi Itsuno Aug 2024

Preparation Of A Chiral Hyperbranched Polymer Based On Cinchona Alkaloids And Investigation Of Its Catalytic Activity In Asymmetric Reactions, Rafiqul Islam, Mohammad Shahid Ullah, Abdus Salam, Shinichi Itsuno

Turkish Journal of Chemistry

Cinchona alkaloid-derived sulfonamides and ester dimers containing chiral hyperbranched polymers have been successfully synthesized and applied as catalysts in asymmetric reactions. Several hyperbranched polymers derived from cinchona alkaloids, incorporating sulfonamides and esters, were synthesized through Mizoroki–Heck coupling polymerization. These polymers were subsequently applied in enantioselective Michael addition reactions. As the prepared polymers are not soluble in frequently used organic solvents, they act as efficient catalysts in the enantioselective reaction of β-ketoesters to nitroolefins, achieving up to 99% enantioselectivity with good yields. The insoluble property allows them to better satisfy “green chemistry” requirements and be used several times without losing the …

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Synthesis, Characterization, And Physico-Chemical Aspects Of A New Pvc-Based Quaternary Triethanol Ammonium Chloride Anionite For Tungsten Recovery, Bahig Atia Aug 2024

Synthesis, Characterization, And Physico-Chemical Aspects Of A New Pvc-Based Quaternary Triethanol Ammonium Chloride Anionite For Tungsten Recovery, Bahig Atia

Turkish Journal of Chemistry

The usability of polyvinyl chloride-based quaternary triethanol ammonium chloride anionite (PVC-TEAC) as a potential extractant for tungstate was investigated to recover tungstate from Gabal Qash Amir, Egypt, assaying 70.91% WO3. Structure elucidation for PVC-TEAC anionite was successfully carried out using several techniques. Experimental measurements, such as pH, agitation time, initial tungsten concentration, anionite dose, co-ions, temperature, and eluting agents, have been optimized. It was found that PVC-TEAC anionite has a maximum capacity of 63 mg per gram. From the distribution isotherm modeling, Langmuir’s model fits the experimental results better than Freundlich’s, with a theoretical value of 61.728 mg g–1. According …

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Exploring The Efficiency Of Nitrogenated Carbon Quantum Dots/Tio2 S-Scheme Heterojunction In Photodegradation Of Ciprofloxacin In Aqueous Environments, Yilmaz Ateş, Zafer Eroğlu, Özkan Açişli, Önder Meti̇n, Semra Karaca Aug 2024

Exploring The Efficiency Of Nitrogenated Carbon Quantum Dots/Tio2 S-Scheme Heterojunction In Photodegradation Of Ciprofloxacin In Aqueous Environments, Yilmaz Ateş, Zafer Eroğlu, Özkan Açişli, Önder Meti̇n, Semra Karaca

Turkish Journal of Chemistry

The usability of polyvinyl chloride-based quaternary triethanol ammonium chloride anionite (PVC-TEAC) as a potential extractant for tungstate was investigated to recover tungstate from Gabal Qash Amir, Egypt, assaying 70.91% WO3. Structure elucidation for PVC-TEAC anionite was successfully carried out using several techniques. Experimental measurements, such as pH, agitation time, initial tungsten concentration, anionite dose, co-ions, temperature, and eluting agents, have been optimized. It was found that PVC-TEAC anionite has a maximum capacity of 63 mg per gram. From the distribution isotherm modeling, Langmuir’s model fits the experimental results better than Freundlich’s, with a theoretical value of 61.728 mg g–1. According …

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Liquefaction Optimization Of Grape Pulp Using Response Surface Methodology For Biopolyol Production And Bio-Based Polyurethane Foam Synthesis, Furkan Çolakoğlu, Emre Akdoğan, Murat Erdem Aug 2024

Liquefaction Optimization Of Grape Pulp Using Response Surface Methodology For Biopolyol Production And Bio-Based Polyurethane Foam Synthesis, Furkan Çolakoğlu, Emre Akdoğan, Murat Erdem

Turkish Journal of Chemistry

Both environmental and economic disadvantages of using petroleum-based products have been forcing researchers to work on environmentally friendly, sustainable, and economical alternatives. The purpose of this study is to optimize the solvothermal liquefaction process of grape pomace using response surface methodology coupled with a central composite design. After investigating the physicochemical properties of the liquified products (biopolyol) in detail, a bio-based rigid polyurethane foam (RPUF) was synthesized and characterized. The hydroxyl and acid numbers and viscosity values of all the biopolyols were analyzed. According to variance analysis results (%95 confidence range), both the reaction temperature and catalyst loading were determined …

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New Imidazolidindionedioximes And Their Pt(Ii) Complexes: Synthesis And Investigation Of Their Antitumoral Activities On Breast Cancer Cells, Emrah Karahan, Tuğba Gençoğlu Katmerli̇kaya, Emel Önal, Aydan Dağ, Ayşe Gül Gürek, Vefa Ahsen Aug 2024

New Imidazolidindionedioximes And Their Pt(Ii) Complexes: Synthesis And Investigation Of Their Antitumoral Activities On Breast Cancer Cells, Emrah Karahan, Tuğba Gençoğlu Katmerli̇kaya, Emel Önal, Aydan Dağ, Ayşe Gül Gürek, Vefa Ahsen

Turkish Journal of Chemistry

Breast cancer is one of the most common types of cancer worldwide and has the most lethality ratio for females among all cancers. Although current cancer therapeutics have made considerable advancements, there is still room for improvement in terms of efficacy. Many anticancer drugs have a risk of causing serious adverse effects due to their non-specific cytotoxic effects on both tumor and healthy cells. New therapeutics might have a greater ability to kill cancer cells, reduce the volume of tumors, and improve overall therapy response rates. Herein, we report the efficient synthesis and characterization of three amphi vic-dioximes and their …

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Synthesis Of 3-Methyl-3-Buten-1-Ol By Supercritical Co2 In Coordination With Hzsm-5 Catalyzed Formaldehyde-Isobutene Prins Reaction, Hang Yuan, Gui-Ping Cao, Hui Lv Aug 2024

Synthesis Of 3-Methyl-3-Buten-1-Ol By Supercritical Co2 In Coordination With Hzsm-5 Catalyzed Formaldehyde-Isobutene Prins Reaction, Hang Yuan, Gui-Ping Cao, Hui Lv

Turkish Journal of Chemistry

The reaction solvent and catalyst play an essential role in the Prins reaction for the synthesis of 3-methyl-3-buten-1-ol (MBO) from formaldehyde and isobutene. The reactivity of the solid base catalyzed Prins condensation reaction by formaldehyde and isobutene in supercritical CO2 was investigated using CsH2PO4 modified HZSM-5. We finds that the alkaline sites of the alkali-loaded catalyst can extract the α-H on isobutene to generate olefin carbon negative ions, while the supercritical CO2 with weak Lewis acidity can activate formaldehyde to carbon positive ions, which can combine more easily with the carbon negative isobutene to react, thus improving the reactivity of …

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Magnetic Solid-Phase Extraction Technique Based On Fe3o4@Coppy-Pth Nanocomposite For Extraction Of Cobalt, Chromium, And Nickel Prior To Determination By Micro-Sample Injection System-Flame Atomic Absorption Spectrometry In Alcoholic And Nonalcoholic Beverages, Meli̇ke Küçüksakalli, Qamar Salamat, Buket Ti̇reli̇, Şükrü Gökhan Elçi̇ Aug 2024

Magnetic Solid-Phase Extraction Technique Based On Fe3o4@Coppy-Pth Nanocomposite For Extraction Of Cobalt, Chromium, And Nickel Prior To Determination By Micro-Sample Injection System-Flame Atomic Absorption Spectrometry In Alcoholic And Nonalcoholic Beverages, Meli̇ke Küçüksakalli, Qamar Salamat, Buket Ti̇reli̇, Şükrü Gökhan Elçi̇

Turkish Journal of Chemistry

A novel Fe3O4@coPPy-PTH nanocomposite-based sorbent was prepared via in-situ oxidative polymerization using Fe3O4 nanoparticles with spherical and flower-like morphologies of thiophene and pyrrole as the feedstocks. The synthesized nanocomposite utilized sensitive extraction and determination of the metal ions Co(II), Cr(III), and Ni(II) without a chelating agent, followed by a micro-sample injection system-flame atomic absorption spectrometer (MIS-FAAS). The composition and morphology of Fe3O4@coPPy-PTH nanocomposite were characterized by advanced spectroscopic and imaging techniques like SEM and FT-IR. SEM observations showed the size of Fe3O4 nanoparticles changed from 30 nm to 120 nm in diameter after the copolymer (PPy-PTH) coating. The Fe3O4@coPPy-PTH nanocomposite …

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Β-Ketoenamine-Linked Covalent Organic Framework For Efficient Iodine Capture, Onur Büyükçakir Aug 2024

Β-Ketoenamine-Linked Covalent Organic Framework For Efficient Iodine Capture, Onur Büyükçakir

Turkish Journal of Chemistry

Exploring the materials that effectively capture radioactive iodine is crucial in managing nuclear waste produced from nuclear power plants. Herein, a β-ketoenamine-linked covalent organic framework (bCOF) was reported as an effective adsorbent to capture iodine from both vapor and solution. bCOF's high porosity and heteroatom-rich skeleton offer a notable iodine vapor uptake capacity of up to 2.51 g g-1 at 75 oC under ambient pressure. Furthermore, after five consecutive adsorption-desorption cycles, the bCOF demonstrates a high reusability performance with a significant iodine vapor capacity retention. The adsorption mechanism was also investigated using various ex-situ structural characterization techniques, and these mechanistic …

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Lacoo3 Is A Promising Catalyst For Dry Reforming Of Benzene Used As A Surrogate Of Biomass Tar, Başar Çağlar, Deni̇z Üner Aug 2024

Lacoo3 Is A Promising Catalyst For Dry Reforming Of Benzene Used As A Surrogate Of Biomass Tar, Başar Çağlar, Deni̇z Üner

Turkish Journal of Chemistry

Tar build-up is one of the bottlenecks of biomass gasification process. Dry reforming of tar is an alternative solution if oxygen chemical potential on the catalyst surface is at sufficient levels. For this purpose, an oxygen donor perovskite, LaCoO3, was used as a catalyst for dry reforming of tar. To circumvent the complexity of the tar and its constituents, benzene molecule was chosen as a model compound. Dry reforming of benzene vapour on the LaCoO3 catalyst was investigated at temperatures of 600, 700, 800 °C, at the CO2/C6H6 ratios of 3, 6, 12 and at space velocities of 14000 and …

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Synthesis And Characterization Of New Hexahydroquinoline Derivatives, Evaluation Of Their Cytotoxicity, Intracellular Ros Production And Inhibitory Effects On Inflammatory Mediators, Ezgi̇ Pehli̇vanlar, Deni̇z Arca Çakir, Sonia Sanajou, Hülya Tezel Yalçin, Terken Baydar, Pinar Erkekoğlu, Hani̇fe Avci, Rahi̇me Şi̇mşek Aug 2024

Synthesis And Characterization Of New Hexahydroquinoline Derivatives, Evaluation Of Their Cytotoxicity, Intracellular Ros Production And Inhibitory Effects On Inflammatory Mediators, Ezgi̇ Pehli̇vanlar, Deni̇z Arca Çakir, Sonia Sanajou, Hülya Tezel Yalçin, Terken Baydar, Pinar Erkekoğlu, Hani̇fe Avci, Rahi̇me Şi̇mşek

Turkish Journal of Chemistry

Inflammation is a response to injury and infection in the organism. It can be categorized as acute and chronic inflammation. Chronic inflammation is the underlying cause of many diseases such as Alzheimer's, diabetes, rheumatoid arthritis, atherosclerosis and cardiovascular diseases. Recent studies have proven the anti-inflammatory properties of 1,4-dihydropyridines (1,4-DHPs) and its derivatives, which have many biological properties including calcium channel blockers. The structures of the synthesized compounds were elucidated by IR, 1H-NMR, 13C-NMR and HRMS methods. The cytotoxic properties of the compounds were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method in 3T3 cell line. Among the 15 compounds, the three compounds …

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Identification Of Blood At Simulated Crime Scenes Using Silver Nanoparticles With Sers, Uğur Köroğlu, Necdet Sağlam, Uğur Tamer, Ramazan Akcan, İsmai̇l Hakki Boyaci, Eylül Evran Aug 2024

Identification Of Blood At Simulated Crime Scenes Using Silver Nanoparticles With Sers, Uğur Köroğlu, Necdet Sağlam, Uğur Tamer, Ramazan Akcan, İsmai̇l Hakki Boyaci, Eylül Evran

Turkish Journal of Chemistry

Analysis of substances and samples obtained from the crime scene are very important in solving forensic cases. In order to determine the variables involved in a crime and to expedite the investigation process, especially the rapid analysis of body fluids in a small quantity and within an environment containing diverse components is necessary. For this reason, it is of great importance to analyse biological fluids with rapid, non-chemical contamination, non-destructive, low-cost and accurate techniques. In recent years, with advancements in laser technology, spectroscopic methods have been introduced as an analytical technique in forensic medicine and chemical studies. This study focuses …

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Synthesis And Photooxygenation Of 3-(P-Substituted Phenyl)-3a,8a-Dihydro-4h-Cyclohepta[D]Isoxazoles: Facial Selectivity, Mahi̇re Emel Olgun, Abdullah Menzek, Ertan Şahi̇n, Yasi̇n Çeti̇nkaya Aug 2024

Synthesis And Photooxygenation Of 3-(P-Substituted Phenyl)-3a,8a-Dihydro-4h-Cyclohepta[D]Isoxazoles: Facial Selectivity, Mahi̇re Emel Olgun, Abdullah Menzek, Ertan Şahi̇n, Yasi̇n Çeti̇nkaya

Turkish Journal of Chemistry

Two 3-(p-substituted phenyl)-3a,8a-dihydro-4H-cyclohepta[d]isoxazoles were synthesized by 1,3-dipolar cycloaddition of the corresponding nitrile oxides with cycloheptatriene. Two endoperoxides were synthesized as facially selective and single products in high yields (93-95%) from the reactions of isoxazole derivatives with singlet oxygen. The exact configurations of the endoperoxide with a methyl group in the phenyl ring and the diol synthesized from it were confirmed by X-ray analysis. To elucidate the mechanism, the formation energy of the endoperoxide was investigated by simulations using the software package Gaussian 09 and density functional theory calculations via the M06-2X/6-311+G(d,p) level method in dichloromethane. The results were consistent with …

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Corrigendum To “Polybrominated Methoxy- And Hydroxynaphthalenes” [Turkish Journal Of Chemistry 40 (2) 2016 332-346 ], Kiymet Berki̇l Akar, Osman Çakmak, Tuncay Tunç Aug 2024

Corrigendum To “Polybrominated Methoxy- And Hydroxynaphthalenes” [Turkish Journal Of Chemistry 40 (2) 2016 332-346 ], Kiymet Berki̇l Akar, Osman Çakmak, Tuncay Tunç

Turkish Journal of Chemistry

This corrigendum is to address an issue regarding the manuscript’s previous publication. The authors have regrettably noticed that the incorrect version of the figure and crystal data was used in the original published version of this paper. To rectify this oversight and ensure the accuracy of the published work the correct figure and data are included for your reference.

Link to the original article: https://journals.tubitak.gov.tr/chem/vol40/iss2/11/

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Hot Wire Chemical Vapor Deposition Of Tungsten Oxides For Photocatalytic Hydrogen Production From Water, Marvin Bonney Aug 2024

Hot Wire Chemical Vapor Deposition Of Tungsten Oxides For Photocatalytic Hydrogen Production From Water, Marvin Bonney

Theses and Dissertations

Anthropogenic climate change has generated an ever-increasing global ecological, economic, and political disaster for the world. In order to contain the damage and bring atmospheric carbon under control, human use of non-renewable hydrocarbons as the primary source of fuels for transportation and electrical generation needs to be phased out at the earliest possible date. Renewable, clean energy generation is currently technologically feasible and could provide the means for decarbonization of the global energy economy, but has to overcome challenges related to the intermittency of production. Hydrogen gas is a clean burning, renewable, and highly flexible method of storing such energy …

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Evaluating Audio-Compression Techniques, Thien Tuong Duong Aug 2024

Evaluating Audio-Compression Techniques, Thien Tuong Duong

Theses and Dissertations

Perceptual quality of audio is the aural accuracy and fidelity perceived by the listener. It is how humans respond to the accuracy, intelligibility, or fidelity of aural media. High-fidelity audio represents high accuracy and minimal distortion and is the standard against which compression algorithms are assessed. We argue that maintaining high-fidelity audio is not just a technical requirement but is also about respecting the artistry of music production. The primary goal of this thesis is to compare the performance of popular audio codecs including file size and conversion speed of each codec when encoding the same file. A secondary goal …

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Data Communication Over Power-Lines: A Review On Technical, And Applications Challenges, Abdi Abdalla Aug 2024

Data Communication Over Power-Lines: A Review On Technical, And Applications Challenges, Abdi Abdalla

Tanzania Journal of Engineering and Technology (TJET)

This paper presents a review study on the data communication over power-lines, commonly referred to as power-line carrier, power-line communication (PLC), mains communications, or power-line digital subscriber line (PDSL). This study examines the technical and application advantages and challenges associated with adopting PLC as a preferred alternative technology for wideband or broadband data communication. The broader coverage area of the PLC network gives it a distinct advantage over other communication network technologies. Additionally, implementing a communication system using the existing power-line network is more cost-effective and less time-consuming compared to constructing a new network from scratch. However, the primary challenge …

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Development And Testing Of Small-Scale Flash Dryer For Maize Bran, Eden Ngowi Aug 2024

Development And Testing Of Small-Scale Flash Dryer For Maize Bran, Eden Ngowi

Tanzania Journal of Engineering and Technology (TJET)

Sun drying is the most common technique used to dry various food products due to its economic convenience. However, it is not effective owing to its unreliable nature leading to microbial deterioration and aflatoxin contamination of food. In Tanzania, about 1.3 million tonnes of maize bran are at risk of deterioration annually due to improper drying. The aim of this study was to design, fabricate and test an efficient small-scale flash dryer for maize bran. Using principles of material and energy balance, a small-scale flash dryer with a throughput of 500 kg of dry product per hour was designed resulting …

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Exploring The Transformation Of Sustainable Collective Spaces: A Study From Mlalakuwa Informal Settlement, Jacob Lutta Aug 2024

Exploring The Transformation Of Sustainable Collective Spaces: A Study From Mlalakuwa Informal Settlement, Jacob Lutta

Tanzania Journal of Engineering and Technology (TJET)

A major challenge in collective space transformation is addressing the complexity of informal urbanisation in developing countries. Using a case study approach, this paper examines the concerns related to a particular informal settlement's sustainable collective space transformation. One of the key findings is that the absence of formal rules and regulations in the development of informal settlements in combination with land-grabbing leads to the absence of open spaces that could be used collectively. It is observed that sustainability in urban development is another body of critical thought that integrates several streams of current urban elements and embodies various conceptions of …

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Investigations Of Cell Tower Antennas Parameters On Reduction Of Radio Frequency Radiation Levels From Radio Base Stations, Florence U. Rashidi Aug 2024

Investigations Of Cell Tower Antennas Parameters On Reduction Of Radio Frequency Radiation Levels From Radio Base Stations, Florence U. Rashidi

Tanzania Journal of Engineering and Technology (TJET)

The widespread deployment of mobile cellular base stations in populated areas has raised public health concerns due to increased exposure to radio frequency (RF) radiation emissions. Exposure to high levels of RF radiation can have potential thermal and non-thermal biological effects. Optimizing the configuration of cell tower antenna parameters is crucial for mitigating these radiation levels. This study therefore aims at systematically investigating the influence of different cell tower antenna parameters on reducing the RF radiation levels from mobile base stations. Field measurements were conducted at two cell sites shared by multiple mobile operators. Electric field strengths were measured at …

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Evaluation Of Business-Driven Reference Architecture For Big Data Analytics Implementation By Public Sector Organizations In Resource-Constrained Setting: A Case Study Of Uganda, Matendo Didas Aug 2024

Evaluation Of Business-Driven Reference Architecture For Big Data Analytics Implementation By Public Sector Organizations In Resource-Constrained Setting: A Case Study Of Uganda, Matendo Didas

Tanzania Journal of Engineering and Technology (TJET)

Big Data Analytics (BDA) is a new area at the nexus of agenda, public sector organizations, and government business. It may satisfy the growing need for trustworthy, cost-effective services in the public sector for better, more informed decision-making processes. BDA has been proposed on the planning schedules of several public sector organizations and the government. Therefore, from the previous work, using Uganda as a case study, specifically the Uganda Bureau of Statistics (UBOS), Ministry of Health (MoH), and Ministry of Education and Sports (MoES), this study aims to evaluate a designed Business-Driven Reference Architecture for Big Data Analytics Implementation (BRABDAI) …

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