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2022

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Articles 16441 - 16470 of 18310

Full-Text Articles in Physical Sciences and Mathematics

Robophobia, Andrew Keane Woods Jan 2022

Robophobia, Andrew Keane Woods

University of Colorado Law Review

Robots-machines, algorithms, artificial intelligence-play an increasingly important role in society, often supplementing or even replacing human judgment. Scholars have rightly become concerned with the fairness, accuracy, and humanity of these systems. Indeed, anxiety about machine bias is at a fever pitch. While these concerns are important, they nearly all run in one direction: we worry about robot bias against humans; we rarely worry about human bias against robots.

This is a mistake. Not because robots deserve, in some deontological sense, to be treated fairly-although that may be true-but because our bias against nonhuman deciders is bad for us. For example, …


Electroencephalogram Classification Of Brain States Using Deep Learning Approach, Hrishitva Patel Jan 2022

Electroencephalogram Classification Of Brain States Using Deep Learning Approach, Hrishitva Patel

Computer Science Faculty Scholarship

The oldest diagnostic method in the field of neurology is electroencephalography (EEG). To grasp the information contained in EEG signals, numerous deep machine learning architectures have been developed recently. In brain computer interface (BCI) systems, classification is crucial. Many recent studies have effectively employed deep learning algorithms to learn features and classify various sorts of data. A systematic review of EEG classification using deep learning was conducted in this research, resulting in 90 studies being discovered from the Web of Science and PubMed databases. Researchers looked at a variety of factors in these studies, including the task type, EEG pre-processing …


Silver Microparticle-Enhanced Laser-Induced Breakdown Spectroscopy, Jeremy C. Marvin, Emma J. Blanchette, Sydney C. Sleiman, Haiqa Arain, Emily A. Tracey, Steven J. Rehse Jan 2022

Silver Microparticle-Enhanced Laser-Induced Breakdown Spectroscopy, Jeremy C. Marvin, Emma J. Blanchette, Sydney C. Sleiman, Haiqa Arain, Emily A. Tracey, Steven J. Rehse

Physics Publications

Enhanced emission was observed in the laser-induced breakdown spectroscopy (LIBS) atomic emission spectra of bacterial cells deposited upon a nitrocellulose filtration medium in the presence of one-micron silver microparticles. A deposition chamber was constructed that allowed a uniform coating of the filter with trace amounts of silver microparticles. Masses from 10 to 100 μg were deposited in a circular area of 52.18 mm2. A 30 s deposition time was used for all experiments resulting in a mass deposition of 39 μg ± 17 μg. This mass coverage on the filter provided for a single laser shot silver mass ablation of …


A Gis Analysis Of Potential Wetland Mitigation Opportunities In The Brandywine Creek Watershed, Chester County, Pennsylvania, Shannon Ryan Jan 2022

A Gis Analysis Of Potential Wetland Mitigation Opportunities In The Brandywine Creek Watershed, Chester County, Pennsylvania, Shannon Ryan

West Chester University Master’s Theses

Wetlands provide innumerous functions and values that are beneficial to both the natural environment and economic systems. Historically these habitats have suffered significant losses and it is crucial to preserve existing wetlands and plan for future restoration opportunities. This research examines six sub-watersheds within the Brandywine Creek watershed within Chester County, Pennsylvania to determine where potential wetland mitigation opportunities occur. Using a Geographic Information Systems (GIS) analysis, three wetland characteristics including watercourse locations, existing National Wetlands Inventory (NWI) wetlands, and hydric soils were mapped throughout each of the watersheds. Areas of agricultural easements and steep slopes were used to exclude …


Inverse Boundary Value Problems For Polyharmonic Operators With Non-Smooth Coefficients, Landon Gauthier Jan 2022

Inverse Boundary Value Problems For Polyharmonic Operators With Non-Smooth Coefficients, Landon Gauthier

Theses and Dissertations--Mathematics

We consider inverse boundary problems for polyharmonic operators and in particular, the problem of recovering the coefficients of terms up to order one. The main interest of our result is that it further relaxes the regularity required to establish uniqueness. The proof relies on an averaging technique introduced by Haberman and Tataru for the study of an inverse boundary value problem for a second order operator.


Batch Normalization Preconditioning For Neural Network Training, Susanna Luisa Gertrude Lange Jan 2022

Batch Normalization Preconditioning For Neural Network Training, Susanna Luisa Gertrude Lange

Theses and Dissertations--Mathematics

Batch normalization (BN) is a popular and ubiquitous method in deep learning that has been shown to decrease training time and improve generalization performance of neural networks. Despite its success, BN is not theoretically well understood. It is not suitable for use with very small mini-batch sizes or online learning. In this work, we propose a new method called Batch Normalization Preconditioning (BNP). Instead of applying normalization explicitly through a batch normalization layer as is done in BN, BNP applies normalization by conditioning the parameter gradients directly during training. This is designed to improve the Hessian matrix of the loss …


Tropical Geometry Of T-Varieties With Applications To Algebraic Statistics, Joseph Cummings Jan 2022

Tropical Geometry Of T-Varieties With Applications To Algebraic Statistics, Joseph Cummings

Theses and Dissertations--Mathematics

Varieties with group action have been of interest to algebraic geometers for centuries. In particular, toric varieties have proven useful both theoretically and in practical applications. A rich theory blending algebraic geometry and polyhedral geometry has been developed for T-varieties which are natural generalizations of toric varieties. The first results discussed in this dissertation study the relationship between torus actions and the well-poised property. In particular, I show that the well-poised property is preserved under a geometric invariant theory quotient by a (quasi-)torus. Conversely, I argue that T-varieties built on a well-poised base preserve the well-poised property when the base …


Determining Power System Fault Location Using Neural Network Approach, Edward O. Ojini Jan 2022

Determining Power System Fault Location Using Neural Network Approach, Edward O. Ojini

Theses and Dissertations--Electrical and Computer Engineering

Fault location remains an extremely pivotal feature of the electric power grid as it ensures efficient operation of the grid and prevents large downtimes during fault occurrences. This will ultimately enhance and increase the reliability of the system. Since the invention of the electric grid, many approaches to fault location have been studied and documented. These approaches are still effective and are implemented in present times, and as the power grid becomes even more broadened with new forms of energy generation, transmission, and distribution technologies, continued study on these methods is necessary. This thesis will focus on adopting the artificial …


Design Of An Accelerator-Based Shielding Experiment At The Nasa Space Radiation Laboratory Relevant To Enclosed, Shielded Environments In Space, Lawrence H Heilbronn, Michael Sivertz, Adam Rusek, Charlie Pearson, Martha Clowdsley, Luis Castellanos, Natalie Mcgirl, Ashwin Srikrishna, Cary Zeitlin Jan 2022

Design Of An Accelerator-Based Shielding Experiment At The Nasa Space Radiation Laboratory Relevant To Enclosed, Shielded Environments In Space, Lawrence H Heilbronn, Michael Sivertz, Adam Rusek, Charlie Pearson, Martha Clowdsley, Luis Castellanos, Natalie Mcgirl, Ashwin Srikrishna, Cary Zeitlin

Faculty Publications and Other Works -- Nuclear Engineering

Recent calculations indicate that the dose equivalent in an enclosed, shielded environment in a galactic cosmic ray field will increase or remain unchanged when shielding thickness increases beyond 20 to 30 g/cm2. This trend is seen out to 100 g/cm2, beyond which calculations were not run since depths greater than this are not envisioned for human missions in deep space. If these calculations are accurate, then an optimal shielding thickness (or narrow range of thicknesses) exists, with important implications for spacecraft and habitat design. Crucially, the calculation reveals a minimum dose equivalent value that cannot be reduced with added shielding, …


Interpretable Design Of Reservoir Computing Networks Using Realization Theory, Wei Miao, Vignesh Narayanan, Jr-Shin Li Jan 2022

Interpretable Design Of Reservoir Computing Networks Using Realization Theory, Wei Miao, Vignesh Narayanan, Jr-Shin Li

Publications

The reservoir computing networks (RCNs) have been successfully employed as a tool in learning and complex decision-making tasks. Despite their efficiency and low training cost, practical applications of RCNs rely heavily on empirical design. In this article, we develop an algorithm to design RCNs using the realization theory of linear dynamical systems. In particular, we introduce the notion of α-stable realization and provide an efficient approach to prune the size of a linear RCN without deteriorating the training accuracy. Furthermore, we derive a necessary and sufficient condition on the irreducibility of the number of hidden nodes in linear RCNs based …


Analysis, Processing, And Migration Of The Marine 4-Component Walkaway Vsp Data Set From The Seg Seam-1 Gulf Of Mexico Salt Elastic Modelling Project: Synthetic Study, Cemal Erdemi̇r Jan 2022

Analysis, Processing, And Migration Of The Marine 4-Component Walkaway Vsp Data Set From The Seg Seam-1 Gulf Of Mexico Salt Elastic Modelling Project: Synthetic Study, Cemal Erdemi̇r

Turkish Journal of Earth Sciences

The four component (4C) walkaway vertical seismic profile (WVSP) marine elastic synthetic data set from the SEG's SEAM-1 salt modeling project in the Gulf of Mexico (GOM) are examined, analyzed, processed, and migrated for P-P reflections using a reverse time prestack migration (RTM) algorithm to construct a subsurface image around the Well-1 VSP borehole. The imaging results from the three data sets; pressure-p, geophone vertical (z), and horizontal inline (x) components, have shown great successes in correctly locating and imaging sediments near and below the borehole as well as the vertical face of the salt, which is about 5 km …


Middle-Late Devonian Boundary Conodonts From Anarak And Sar-Ashk Sections, Centraliran, Hossein Gholamalian, Vachik Hairapetian, Mohammad Poosti Jan 2022

Middle-Late Devonian Boundary Conodonts From Anarak And Sar-Ashk Sections, Centraliran, Hossein Gholamalian, Vachik Hairapetian, Mohammad Poosti

Turkish Journal of Earth Sciences

The Middle/Late Devonian boundary is investigated based on twenty-four conodont species and subspecies from the Anarak and Sar-Ashk sections in the northwest and southeast of Central East Iran Microplate. The earliest Frasnian strata are defined by the first appearance of Ancyrodella rotundiloba pristina and can be correlated with the global stratotype in the Montagne Noir, South of France. The Late Givetian - Early Frasnian carbonates of the Bahram Formation in the Sar-Ashk section transgressively overlie the sandstones of the Padeha Formation, whereas the coeval interval in the Anarak section composes the middle part of the Bahram Formation. Conodont biostratigraphy of …


Exploring The Untapped Gas Potential Of Ghazij Shale In Pirkoh Area, Pakistan: Integratedapproach Of Attribute Analysis And Maturity Modeling, Muhammad Raiees Amjad, Sarfraz Khan, Umair Bin Nisar, Urooj Shakir, Khawar Ashfaq Ahmed Jan 2022

Exploring The Untapped Gas Potential Of Ghazij Shale In Pirkoh Area, Pakistan: Integratedapproach Of Attribute Analysis And Maturity Modeling, Muhammad Raiees Amjad, Sarfraz Khan, Umair Bin Nisar, Urooj Shakir, Khawar Ashfaq Ahmed

Turkish Journal of Earth Sciences

A correlative maturity study integrated with seismic attributes for determining the shale gas potential of Ghazij Formation is carried out. Analysis of post-stack seismic attributes has been frequently used to identify areas of high exploration potential within shale resource plays. Seismic and well data have been utilized for the analysis of maturity trends in the shale facies of Ghazij Formation. Total organic carbon content (TOC), burial history, Vitrinite Reflectance (Ro), thermal history and porosity values have been computed at Pirkoh-01 well, which are laterally compared with the maturity results in Bambor and Sui areas. In addition, analysis is carried out …


Tectonic And Structural Characteristics Of Erzurum And Its Surroundings(Eastern Turkey): A Detailed Comparison Between Different Geophysical Parameters, Çağlar Özer, Serkan Öztürk, Eren Pamuk Jan 2022

Tectonic And Structural Characteristics Of Erzurum And Its Surroundings(Eastern Turkey): A Detailed Comparison Between Different Geophysical Parameters, Çağlar Özer, Serkan Öztürk, Eren Pamuk

Turkish Journal of Earth Sciences

The tectonic and structural properties of Erzurum and its surroundings have been investigated by evaluating the seismotectonic b - value, magnetic anomaly, edge detection analysis (total horizontal derivative (THDR) and tilt angle (TA)), Curie Point Depth (CPD), P-wave velocity (Vp), and Vp / Vs (S - wave velocity) ratio and by imaging the regional distributions of these parameters. For this purpose, all parameters have been combined to be able to reveal the new useful results on the study region and are presented for different locations and depths. The Vp values have been accompanied by high Vp / Vs ratios and …


Modelling Muscle Activation Using Emg Signal, Mercy U. Okonna Jan 2022

Modelling Muscle Activation Using Emg Signal, Mercy U. Okonna

Electronic Theses and Dissertations

(EMG) is a method for measuring muscle activity by an electrical signal, and is useful in studying motor control, postural control, and in physical therapy. A current research topic is creating an algorithm that can use the EMG signal to reliably classify a muscle as active or inactive. This thesis presents a classification algorithm for leg muscles with a single activation spike while walking. Time is rescaled into steps, which are identified using data from cameras measuring joint angles while walking. The algorithm is based on moving averages and a convex combination of mean signal strength in active and inactive …


Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover Jan 2022

Biomimetic Synthesis Of Palladium Nanoparticles For Catalytic Application, Emily A. Groover

Electronic Theses and Dissertations

The synthesis of palladium nanoparticles (Pd NPs) using materials-directed peptides is a novel, nontoxic approach which exerts a high level of control over the particle size and shape. This biomimetic technique is environmentally benign, featuring nonhazardous ligands and ambient conditions. Nanoparticles are extremely reactive catalysts, boasting a large surface-to-volume ratio when compared to their bulk counterparts. The rational design of these nanoparticles using peptides has been very successful in aqueous environments, but no research has been done to apply it in organic systems. As such, the biomimetic synthesis of Pd NPs in an organic system is here investigated, with ethanol …


Molybdenum Oxide/Antimony Nanobelts Embedded In Asymmetric Membranes For Use As High-Capacity Lithium/Sodium-Ion Battery Anodes, Logan Williams Jan 2022

Molybdenum Oxide/Antimony Nanobelts Embedded In Asymmetric Membranes For Use As High-Capacity Lithium/Sodium-Ion Battery Anodes, Logan Williams

Electronic Theses and Dissertations

Lithium-ion batteries (LIB) are a key aspect of our daily lives, from smartphones to electric vehicles. Commercially available LIB use graphite anodes due to their reliability and safety. Graphite anodes present one key disadvantage: a relatively low theoretical capacity of 372 mAh g-1. It is of great importance that new research focuses on high-capacity anode materials to further our sustainability and usage of LIB. While increasing the performance of LIB is of great interest, developing alternative energy storage devices is gaining attention in academia and industry R&D. Sodium has become a topic of interest in recent years due to sodium’s …


Design And Implementation Of An Automatic Word Generator For Word Matching Interactives, Evan Miles Gertis Jan 2022

Design And Implementation Of An Automatic Word Generator For Word Matching Interactives, Evan Miles Gertis

Electronic Theses and Dissertations

An Automatic Word Match Generator is a software tool that can be used to generate word-matching interactives automatically. The purpose of a word-matching interactive is to provide students with the mechanism to learn new vocabulary and improve their reading comprehension skills. This thesis will present the design and implementation of an Automatic Word Match Generator, as well as the research and algorithms used in the program.


Using Ai-Enabled Gaze Tracking System To Understand Comprehension Patterns Of Computer Science Students, Bradley Boswell Jan 2022

Using Ai-Enabled Gaze Tracking System To Understand Comprehension Patterns Of Computer Science Students, Bradley Boswell

Electronic Theses and Dissertations

Academic institutions and instructors lack the ability to accurately assess the moment-to-moment attentiveness of students in classrooms where students’ faces are obscured by computer monitors. This can cause the lectures of Computer Science, Information Technology, or other lab-based courses to be incorrectly-paced, which can lead to students having an overall poorer grasp of the subject material. We propose a system for real-time accurate detection of classroom attentiveness using monitor-mounted webcams and eye trackers, along with a Convolutional Neural Network machine learning model (NiCATS). Through the use of a neural network, we produce an initial attentiveness score based on student webcam …


Developing And Validating A Machine Learning-Based Student Attentiveness Tracking System, Andrew L. Sanders Jan 2022

Developing And Validating A Machine Learning-Based Student Attentiveness Tracking System, Andrew L. Sanders

Electronic Theses and Dissertations

Academic instructors and institutions desire the ability to accurately and autonomously measure the attentiveness of students in the classroom. Generally, college departments use unreliable direct communication from students (i.e. emails, phone calls), distracting and Hawthorne effect-inducing observational sit-ins, and end-of-semester surveys to collect feedback regarding their courses. Each of these methods of collecting feedback is useful but does not provide automatic feedback regarding the pace and direction of lectures. Young et al. discuss that attention levels during passive classroom lectures generally drop after about ten to thirty minutes and can be restored to normal levels with regular breaks, novel activities, …


Non-Inferiority Testing: Kernel Estimation And Overlap Measure, Larie C. Ward Jan 2022

Non-Inferiority Testing: Kernel Estimation And Overlap Measure, Larie C. Ward

Electronic Theses and Dissertations

In non-inferiority testing, the decision of whether a proposed treatment is non-inferior to a reference treatment depends on model assumptions and choices of acceptable tolerance limits. Here, we consider a method that employs kernels to estimate the probability density functions of both the experimental and reference populations from two independent samples. Based on these densities, we introduce a quantity called the overlap coefficient or overlap measure. A bootstrap technique is helpful in exploring the distribution and variance empirically. We derive the distribution of this measure and define a hypothesis test that can be applied to the non-inferiority setting under some …


Investigation Of Intramolecular And Intermolecular Aza-Michael Reactions, Nadia Z. Singleton Jan 2022

Investigation Of Intramolecular And Intermolecular Aza-Michael Reactions, Nadia Z. Singleton

Electronic Theses and Dissertations

The hydroamination of dimaleimides with diamines has been accomplished to access novel polymers. Various dimaleamides and dimaleimides were synthesized from commercially available diamines and maleic anhydride. The resulting dimaleamides were then ring-closed to their respective dimaleimides either directly in the presence of acid or via the synthesis of mixed amide-esters which then ring close in the presence of acid under heat. Hydroamination of the dimaleimides with piperazine was accomplished in bulk at room temperature. The reaction is spontaneous thus leading to the formation of polyimides with high functional group conversion within minutes. The kinetics of the maleamides and maleimides was …


Polymer Based Advanced Recipes For Imidazoles: A Review, Shivnath Patel, Rajendra Patil, Jagdish Chavan, Anil Beldar Jan 2022

Polymer Based Advanced Recipes For Imidazoles: A Review, Shivnath Patel, Rajendra Patil, Jagdish Chavan, Anil Beldar

Turkish Journal of Chemistry

Imidazoles and their scaffold are an extraordinarily essential class of nitrogen bearing azole heterocyclic compounds. They have different place in wide area of organic synthesis, which can be utilized in a variety of applications in diverse fields including agriculture, medicine, polymer and various industries. Numerous methods for synthesis of imidazole derivatives are reported in last few decades. Existing conventional methods are more or less significant and confined due to its time-consuming reactions, high cost of catalyst, extensive methodologies, low yield rate or no reusability respectively. Overcoming to inefficient conventional methods, finding of novel and effective methods of imidazole synthesis becomes …


Synthesis Of Some New Isoxazole Compounds And Their Biological Tyrosinase And Antioxidant Activities, Seda Fandakli Jan 2022

Synthesis Of Some New Isoxazole Compounds And Their Biological Tyrosinase And Antioxidant Activities, Seda Fandakli

Turkish Journal of Chemistry

In this study, 7 new isoxazole compounds (8-14) were synthesized from the cyclization of chalcone compounds (1-7) containing different functional groups with hydroxylamine hydrochloride in alkaline medium. Tyrosinase and antioxidant properties of 8-14 were investigated. IC50 values for the tyrosinase enzyme inhibition of compounds 8, 11, 12, and 13 were varied between 61.47 ± 3.46 and 188.52 ± 5.85, while compounds 9, 10 and 14 did not show any inhibition effect. The antioxidant properties of 8-14 were investigated by DPPH and CUPRAC methods. Compound 12 showed the best DPPH radical scavenging activity (SC50: 40.21 ± 2.71), while 12 and 13 …


Synthesis And In Vitro Α-Glucosidase And Cholinesterases Inhibitory Actions Of Watersolublemetallophthalocyanines Bearing ({6-[3-(Diethylamino)Phenoxy]Hexyl}Oxy Groups, Turgut Keleş, Zekeri̇ya Biyiklioğlu, Di̇dem Akkaya, Arzu Özel, Burak Barut Jan 2022

Synthesis And In Vitro Α-Glucosidase And Cholinesterases Inhibitory Actions Of Watersolublemetallophthalocyanines Bearing ({6-[3-(Diethylamino)Phenoxy]Hexyl}Oxy Groups, Turgut Keleş, Zekeri̇ya Biyiklioğlu, Di̇dem Akkaya, Arzu Özel, Burak Barut

Turkish Journal of Chemistry

In this paper, we have prepared peripherally tetra-({6-[3-(diethylamino)phenoxy]hexyl}oxy substituted cobalt(II), copper(II), manganese(III) phthalocyanines (3, 4, 5) and their water-soluble derivatives (3a, 4a, 5a). Then, in vitro α-glucosidase and cholinesterases inhibitory actions of the water-soluble 3a, 4a, 5a were examined using spectrophotometric methods. 4a had the highest inhibitory effects among the tested compounds against α-glucosidase due to IC50 values. 4a and 5a had 40 fold higher inhibitory effects than the positive control. For cholinesterases, the compounds showed significant inhibitory actions that of galantamine which was used as a positive control. According to the SI value, 3a inhibited acetylcholinesterase enzyme selectively. In …


Ferrihydrite/Ultrasound Activated Peroxymonosulfate For Humic Acid Removal, Hang Yang, Yi Zhang, Shibin Xia Jan 2022

Ferrihydrite/Ultrasound Activated Peroxymonosulfate For Humic Acid Removal, Hang Yang, Yi Zhang, Shibin Xia

Turkish Journal of Chemistry

In this study, ferrihydrite/ultrasound (US) system was used to activate peroxymonosulfate (PMS) to treat humic acid (HA) in artificial aqueous. The physical and chemical properties of ferrihydrite were characterized using SEM, zeta potential, BET, XRD, FTIR, and XPS analysis. A series of experiments were conducted to evaluate the effect of various factor on HA removal, including dosage of ferrihydrite, PMS concentration and pH value. The combination uses of US and ferrihydrite had obvious synergistic effect for HA removal. Under ferrihydrite/US/PMS system, nonthermal effect of US played the main role for HA removal. According to the result of radical quenching experiment, …


Synthesis, Antioxidant Activity, Molecular Docking And Adme Studies Of Novel Pyrrolebenzimidazolederivatives, Fi̇kri̇ye Zengi̇n Karadayi, Rahman Başaran, Mehmet Murat Kişla, Bi̇nay Eke, Zeynep Alagöz Jan 2022

Synthesis, Antioxidant Activity, Molecular Docking And Adme Studies Of Novel Pyrrolebenzimidazolederivatives, Fi̇kri̇ye Zengi̇n Karadayi, Rahman Başaran, Mehmet Murat Kişla, Bi̇nay Eke, Zeynep Alagöz

Turkish Journal of Chemistry

Several 5-(alkylsulfonyl)-1-substituted-2-(1H-pyrrol-2-yl)-1H-benzo[d]imidazole derivatives were synthesized and their antioxidant activities were investigated using lipid peroxidation (LPO) and 7-ethoxyresorufin O-deethylase (EROD) assays. Docking analysis with Human NAD[P]H-Quinone oxidoreductase 1 (NQO1) was also performed to gather thorough information about these compounds that have antioxidant activities. Moreover, their molecular descriptors and ADME properties were calculated using the SwissADME online program. As a result, most of our compounds possessed better affinity and created ample interactions with NQO1. The most potent compound 5j had LP inhibition value of 3.73 nmol/mg/min. Other compounds exhibited moderate activity on LP levels comparing to standard butylated hydroxy toluene (BHT). However, …


Development And Validation Of A New Rp-Hplc Method For Organic Explosive Compounds, Sali̇h Murat Ünsal, Emre Erkan Jan 2022

Development And Validation Of A New Rp-Hplc Method For Organic Explosive Compounds, Sali̇h Murat Ünsal, Emre Erkan

Turkish Journal of Chemistry

A new RP-HPLC method was developed and validated to achieve the separation and quantification of the organic explosive compounds such as pentaerythritol tetranitrate (PETN), 1-methyl-2,4,6-trinitro toluen (TNT), picric acid, 1,3,5,7-tetrazocine (HMX), cyclorimethylenetrinitramine (RDX), 2,4,6 Tri nitro phenyl methyl nitramine (Tetryl), 1-methyl-2,4-dinitro toluen (DNT), ethylene glycol dinitrate (EGDN), and trinitroglycerine (TNG) in this study. The mobile phase composition (IPA percentage in water) and the flow rate was optimized for the separation of the organic explosive compounds. Theoretical plate number (N), capacity factor (k'), resolution (Rs) were used to determine the optimum chromatographic conditions. The most favorable conditions were detected as 22% …


Quantifying Time-Dependent Structural And Mechanical Properties Of Uv-Aged Ldpe Power Cables Insulations, Abdallah Hedir, Ferhat Slimani, Mustapha Moudoud, Omar Lamrous, Tahar Touam, Madjid Teguar, Abderrahmane Haddad, Ali̇ Durmuş Jan 2022

Quantifying Time-Dependent Structural And Mechanical Properties Of Uv-Aged Ldpe Power Cables Insulations, Abdallah Hedir, Ferhat Slimani, Mustapha Moudoud, Omar Lamrous, Tahar Touam, Madjid Teguar, Abderrahmane Haddad, Ali̇ Durmuş

Turkish Journal of Chemistry

This paper reports effects of ultraviolet (UV) light radiation on the physicochemical, electrical and mechanical properties of low-density polyethylene (LDPE) cable insulating materials. Changes in structural and morphological properties of UV-aged samples were characterized by various analytical methods such as attenuated total reflection Fourier transform infrared spectroscopy (ATRFTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Additionally, elongation at break, tensile strength, dielectric strength, and optical properties were also evaluated. Changes in some physical properties of LDPE after exposing to UV irradiation clearly highlighted that the polymer underwent the structural degradation. In addition, it was also …


Synthesis And Investigation Of A Hexyl Substituted Thieno-Fused Bodipy Derivative As A Versatile Near-Ir Fluorophore, Yusuf Çakmak Jan 2022

Synthesis And Investigation Of A Hexyl Substituted Thieno-Fused Bodipy Derivative As A Versatile Near-Ir Fluorophore, Yusuf Çakmak

Turkish Journal of Chemistry

The synthesis, photophysical and electrochemical properties of hexyl thiophene substituted thieno[b]-fused BODIPY structure are reported within this work. One such derivative, HTFBod, has been studied, which is one of the rare compounds that has a maximum absorbance wavelength greater than 750 nm among fused BODIPY compounds. In addition, it preserves its significant spectral properties such as high molar absorptivity and fluorescence quantum yield. Electrochemical characterizations indicated that the compound could be a successful candidate for an organic solar cell donor compound due to its low band gap, which is known to improve the short-circuit current (Jsc) values. The compound could …