Digital Commons Network^™

Qualitative And Quantitative Determination Of The Effective Components Of The Plants In Different Herbal Slimming Products In Turkey By Hplc, Benan Dursunoğlu, Hafi̇ze Yuca, Sefa Gözcü, Bi̇lal Yilmaz, Zühal Güvenalp

Turkish Journal of Chemistry

Obesity is a serious disease that can be due to genetic and environmental reasons and is defined by the World Health Organization as abnormal or excessive fat accumulation that may impair health. There is an increasing trend towards herbal slimming products in obesity treatment. The quality control analysis of these products is important for public health. In this study, new, simple, and sensitive high performance liquid chromatography methods were developed for qualitative and quantitative determination of arbutin, hydroquinone, ursolic acid, chlorogenic acid, epigallocatechin gallate, epigallocatechin, epicatechin gallate, and catechin in eleven herbal slimming products in Turkey containing Camellia sinensis, Ilex …

Enhanced Uptake Capacities And Isosteric Heats Of Co$_{2}$ And Ch$_{4}$ Adsorption On Spent Coffee Ground Activated Carbons Loaded With Metal Ions, Çi̇sem Kirbiyik, Burak Zafer Büyükbekar, Mahmut Kuş, Mustafa Ersöz

Turkish Journal of Chemistry

Low-cost activated carbon (AC) samples obtained from waste coffee grounds were used for CO$_{2}$ and CH$_{4}$ adsorption. ACs were prepared by chemical activation and carbonized at three different temperatures. AC carbonized at 800 $^{\circ}$C showed a relatively high surface area (582.92 m$^{2}$ g$^{-1})$ and high adsorption capacities of 2.6 mmol g$^{-1}$ and 1.1 mmol g$^{-1}$ at 25 $^{\circ}$C for CO$_{2}$ and CH$_{4}$, respectively. Adsorbent samples were prepared by loading of Fe$^{3+}$ metal ions onto ACs and their adsorption capacities were compared with those of nonloaded ACs. As expected, the loading of Fe$^{3+}$ metal ions increased the adsorption capacities at all …

Alpha-Pyrone Glycosides From Scutellaria Salviifolia Benth, Zeynep Doğan, Kan'ichiro Ishiuchi, Toshiaki Makino, İclal Saraçoğlu

Turkish Journal of Chemistry

Scutellaria salviifolia Benth. is an endemic species growing in Turkey that belongs to the family Lamiaceae. As a result of a phytochemical study on the aerial parts of S. salviifolia Benth., two new and 10 known compounds were isolated from the aqueous fraction of methanolic extract. The new compounds are methyl-$\alpha $-pyrone glucosides, 3,4-dihydroxy-6-methylpyran-2-one 3-$O$-$\beta $-glucopyranoside (=scusalvioside A, 1), and 3,4-dihydroxy-6-methylpyran-2-one 3-$O$-$\beta $-(6$'$-$O$-$E$-caffeoyl) glucopyranoside (=scusalvioside B, 2) with new skeletal structures. Along with them, 3 phloroglucinol glucosides [phlorin (3), tadehaginoside (4), and 6$^{\prime \prime} $-$O$-$Z$-$p$-coumaroyl phloroglucinol-1-$O$-$\beta $-glucopyranoside (5)], 6 flavonoids [apigenin (6), apigenin 5-$O$-$\beta $-glucopyranoside (7), isoschaftoside (8), luteolin 7-$O$-$\beta …

Synthesis, Characterization, And Nonlinear Optical Properties Of Some New Series Of S-(5-Aryl-1,3,4-Oxadiazol-2-Yl) 2-Chloroethanethioate Derivatives, Zahra Dono Ghezelbash, Hamideh Motiei, Miri Mahmoody, Karim Akbari Delmaghani

Turkish Journal of Chemistry

In the present investigation, some novel S-(5-aryl-1,3,4-oxadiazol-2-yl)2-chloroethanethioate (3a-3e) derivatives were synthesized and their impact on optical properties was studied. They have also been characterized by elemental analysis and various spectroscopic methods including FTIR, $^{1}$H NMR, $^{13}$C NMR, and UV-Vis techniques. The nonlinear refractive indexes of 3a-3e were also measured in dichloromethane via Z-scan method using a continuous wave diode-pumped laser at 532 nm wavelength. The nonlinear refractive coefficient of compounds was obtained from ${10}^{11}\, \, {m}^{{2}}{/W}$ order. Regarding the appropriate nonlinearity of these compounds, they could be considered good candidates for biooptical and photonic applications. All the synthesized compounds (3a-3e) …

Bisbenzoxazole Derivatives Had An Antiinflammatory Effect On In Vitro Stimulated Macrophages, Furkan Ayaz, Rusmeenee Kheeree, Qadar Ahmed Isse, Ronak Haj Ersan, Özteki̇n Algül

Turkish Journal of Chemistry

Benzoxazoles are DNA base bioisosteres and studies suggest that their derivatives have antiproliferative activities. Based on their antiproliferative activities they have been mostly studied as new generation anticancer drugs. In our study we exploited their antiproliferative effect, aiming to delineate bisbenzoxazole derivatives' (RHE 231 and RHE 238) potential antiinflammatory effect on mouse macrophages that are activated in vitro through danger signal LPS stimulation. RAW 267.4 mammalian macrophages were activated in the presence of our derivatives with or without danger mimic E. coli derived LPS. We present data that support the strong antiinflammatory activity of the bisbenzoxazole derivatives RHE 231 and …

A Theoretical Investigation On The Activation Of Small Molecules By A Disilenide: A Dft Prediction, Cem Burak Yildiz, Akin Azi̇zoğlu

Turkish Journal of Chemistry

Herein, we proposed several mechanistic scenarios for activation of small molecules (NH$_{3}$, CO$_{2}$, CS$_{2}$, H$_{2}$, CH$_{4}$, N$_{2}$, and N$_{2}$O) by a disilicon analogue of a vinyl anion (1H) using density functional theory (DFT) calculations. The DFT results established that all the possible reactions to yield a variety of potential products have an exergonic nature except for the activation of N$_{2}$ with the obtained overall energy of $\Delta $G = 33.6 kcal mol$^{-1}$. Moreover, the highest exergonic character was $\Delta $G = $-$95.8 kcal mol$^{-1}$ for N$_{2}$O. Therefore, the findings reveal that 1H can be considered a suitable candidate for activation …

Synthesis And Spectroscopic Characterization Of New Phthalocyanine Derivatives: Application As Photocatalysts For The Degradation Of Orange G, Yusuf Yilmaz, Kayode Sanusi

Turkish Journal of Chemistry

New derivatives of 2(3),9(10),16(17),23(24)-tetrakis-(6-methylpyridin-2-yloxy)phthalocyanine (Pc) (2b, 2c, and 2d) were synthesized and their structures were characterized by elemental analysis, IR, $^{1}$H NMR, and high-resolution mass spectrometry. The spectral results were in line with the proposed structures. The photodegradation of Orange G (OG) dye in DMSO by the Pc derivatives was investigated. The compounds showed relatively high photodegradation rates that increased with increasing size of the central atoms. The Pc photodegradation rates showed fair correlation with the singlet oxygen generation efficiencies (${\Phi }_{{\Delta }})$. The observed rate constants were higher than the values already reported for other Pcs in the literature …

Toward Using High-Frequency Coastal Radars For Calibration Of S-Ais Based Ocean Vessel Tracking Models, Ben Freidrich

Theses and Dissertations (Comprehensive)

Most of the world relies on ships for transportation, shipping, and tourism. Automatic Identification System messages are transmitted from ships and provide a wealth of positional data on these open ocean vessels. This data is being utilized to determine the optimal path for ships, as well as predicting where a ship may be going in the near future. It has only been in the past decade that Automatic Identification Systems (AIS) signals have been easily received with satellites (S-AIS) so there have been few studies that look at using available information and pairing it with the new abundance of ship …

Towards Secure And Fair Iiot-Enabled Supply Chain Management Via Blockchain-Based Smart Contracts, Amal Eid Alahmadi

Theses and Dissertations (Comprehensive)

Integrating the Industrial Internet of Things (IIoT) into supply chain management enables flexible and efficient on-demand exchange of goods between merchants and suppliers. However, realizing a fair and transparent supply chain system remains a very challenging issue due to the lack of mutual trust among the suppliers and merchants. Furthermore, the current system often lacks the ability to transmit trade information to all participants in a timely manner, which is the most important element in supply chain management for the effective supply of goods between suppliers and the merchants. This thesis presents a blockchain-based supply chain management system in the …

Explainable Neural Attention Recommender Systems, Omer Tal

Theses and Dissertations (Comprehensive)

Recommender systems, predictive models that provide lists of personalized suggestions, have become increasingly popular in many web-based businesses. By presenting potential items that may interest a user, these systems are able to better monetize and improve users’ satisfaction. In recent years, the most successful approaches rely on capturing what best define users and items in the form of latent vectors, a numeric representation that assumes all instances can be described by their respective affiliation towards a set of hidden features. However, recommendation methods based on latent features still face some realworld limitations. The data sparsity problem originates from the unprecedented …

Multiscale Mathematical Modelling Of Nonlinear Nanowire Resonators For Biological Applications, Rosa Fallahpourghadikolaei

Theses and Dissertations (Comprehensive)

Nanoscale systems fabricated with low-dimensional nanostructures such as carbon nanotubes, nanowires, quantum dots, and more recently graphene sheets, have fascinated researchers from different fields due to their extraordinary and unique physical properties. For example, the remarkable mechanical properties of nanoresonators empower them to have a very high resonant frequency up to the order of giga to terahertz. The ultra-high frequency of these systems attracted the attention of researchers in the area of bio-sensing with the idea to implement them for detection of tiny bio-objects. In this thesis, we originally propose and analyze a mathematical model for nonlinear vibrations of nanowire …

Dispersal As A Buffer Against Zooplankton Community Change In Response To Fluctuating Salinity Levels On The Great Plains, Mercedes Huynh

Theses and Dissertations (Comprehensive)

The North American Great Plains is home to thousands of closed-basin lakes that are sensitive to changes in hydrology. Climate change models predict increased aridity in this region over the coming century, which is expected to lead to higher salinity levels in many freshwater lakes. Increases in salinity levels may impact zooplankton communities, as laboratory experiments show that many freshwater species have a low tolerance for elevated salinity levels, and field data demonstrate that salinity is the primary factor structuring aquatic communities on the Great Plains. Changes to zooplankton communities could lead to a trophic cascade based on their important …

Use Of Pre-Industrial Baselines To Assess Sources And Pathways Of Metals In Surface Sediment Of Floodplain Lakes In The Peace-Athabasca Delta (Alberta, Canada), Tanner Owca

Theses and Dissertations (Comprehensive)

The effects of natural resources exploitation in northern Canada on downstream aquatic ecosystems is a concern. Assessing these effects requires comprehensive monitoring practices to better inform stakeholders and environmental stewardship decisions. Here, a monitoring approach is developed and applied to assess metals concentrations in lake surface sediments of the Peace-Athabasca Delta (PAD), northern Alberta, Canada. Since the ecological integrity of the PAD is strongly tied to river floodwaters that are critical for replenishing the delta, and the PAD is located downstream of the Alberta oil sands, concerns have been raised over the potential transport of metal contaminants to the PAD …

Temperature-Dependent Kinetic Studies Of Arsenicals Adsorption From Solution To Hematite Nanoparticles, Sara Soldoozy

Theses and Dissertations (Comprehensive)

Surface chemistry is the study of the chemical and physical phenomena that transpire at interfaces such as liquid-solid, solid-gas, liquid-gas, and liquid-liquid. To study the reactions occurred at the surfaces, surface sensitive techniques come to play. Adsorption of arsenical compounds (liquid adsorbate), particularly arsenate (iAs) and dimethylarsinic acid (DMA), to the surface of iron bearing materials (solid adsorbent) that frequently are found in geosorbents such as hematite (Fe₂O₃) has been studied in this thesis. Arsenical compounds can pollute the environment through natural sources and anthropogenic activities, and ultimately contaminate water. Absorbing these pollutants to a material …

Generative Adversarial Networks For Online Visual Object Tracking Systems, Ghsoun Zin

Theses and Dissertations (Comprehensive)

Object Tracking is one of the essential tasks in computer vision domain as it has numerous applications in various fields, such as human-computer interaction, video surveillance, augmented reality, and robotics. Object Tracking refers to the process of detecting and locating the target object in a series of frames in a video. The state-of-the-art for tracking-by-detection framework is typically made up of two steps to track the target object. The first step is drawing multiple samples near the target region of the previous frame. The second step is classifying each sample as either the target object or the background. Visual object …

Analysis Of Clmr Trees For European And Asian Option Pricing Under Regime-Switching Jump-Diffusion Models, Yaode Sui

Theses and Dissertations (Comprehensive)

In this paper, we study the convergence rates of the multinomial trees constructed by [Costabile, Leccadito, Massabo and Russo, Journal of Computational and Applied Mathematics, 256 (2014), 152 - 167] for European option pricing under the regime-switching jump-diffusion model, which is named as CLMR tree. We also extend the CLMR tree to the pricing of Asian options under the models. Numerical examples are carried out to confirm the theoretical results and the accuracy of computation.

The Torch: Suffolk University College Of Arts & Sciences Honors Program Newsletter, No. 7, Summer 2019, College Of Arts & Sciences Honors Program

Torch Newsletter

No abstract provided.

Sns Optical Fiber Structure Sensor For Direct Detection Of The Phase Transition In C18h38 N-Alkane Material, Wei Han, Marek Rebow, Xiaokang Lian, Dejun Liu, Gerald Farrell, Qiang Wu, Yuliya Semenova

Articles

A singlemode-no-core-singlemode (SNS) fiber structure optical sensor for detecting the solid-liquid phase change in a phase change material: C18H38 n-alkane material (n-octadecane) is proposed and demonstrated. The transmission-type sensor probe consists of a short section of no-core fiber sandwiched between two sections of a singlemode fiber. Phase changes in n-octadecane are accompanied by large step-like variations of its refractive index (RI). Such a large discontinuous change of the n-octadecane’s RI during its phase transition, leads to the corresponding step-like change in the transmitted optical power that can reliably indicate the phase change of the sample in the vicinity of the …

Econophysics And Fractional Calculus: Einstein's Evolution Equation, The Fractal Market Hypothesis, Trend Analysis And Future Price Prediction, Jonathan Blackledge, Derek Kearney, Marc Lamphiere, Raja Rani, Paddy Walsh

Articles

This paper examines a range of results that can be derived from Einstein’s evolution equation focusing on the effect of introducing a Lévy distribution into the evolution equation. In this context, we examine the derivation (derived exclusively from the evolution equation) of the classical and fractional diffusion equations, the classical and generalised Kolmogorov–Feller equations, the evolution of self-affine stochastic fields through the fractional diffusion equation, the fractional Poisson equation (for the time independent case), and, a derivation of the Lyapunov exponent and volatility. In this way, we provide a collection of results (which includes the derivation of certain fractional partial …

Creativity As An Emergent Property Of Complex Educational System, Ceire Monahan, Mika Munakata, Ashwin Vaidya

Department of Mathematics Faculty Scholarship and Creative Works

The importance of creativity in education has been discussed often in the literature. While there remains no agreed-upon definition of creativity, the psychological literature points to traits of a creative person. These include the ability to think outside the box, make connections between seemingly disparate ideas, and question norms. The literature provides several examples of classroom experiments to help foster creativity in the classroom. In science and mathematics, we can start by getting students to recognize mathematics and the sciences as being creative endeavors. While these attempts are noteworthy, they are not necessarily aligned with instructional practices. In this article, …

Designing Tasks And 3d Physical Manipulatives To Promote Students’ Covariational Reasoning, Teo Paoletti, Steven Greenstein, Madhavi Vishnubhotla, Mustafa Mohamed

Department of Mathematics Faculty Scholarship and Creative Works

Constructing and reasoning about covarying quantities is fundamental to students’ modeling of dynamic phenomena. In this report, we describe how we designed and leveraged 3D-printed manipulatives in parallel with iterative task re-design to support middle-grades students (ages 10-14) constructing and reasoning about covarying quantities. We present data from a design experiment to highlight why we adapted the original task to incorporate 3D-printed manipulatives in order to support students’ constructions of mental images of quantities in ways consistent with researcher intentions. In doing so, we highlight how 3D-printing has opened up new possibilities for manipulatives in mathematics education.

Exploring Dynamic Measurement For Volume, Nicole Panorkou

Department of Mathematics Faculty Scholarship and Creative Works

This paper describes our efforts for exploring students’ thinking of Dynamic Measurement for Volume (DYME-V), an approach to volume measurement that engages students in dynamic experiences of extruding surfaces to create 3-D objects and assists students in reasoning about volume as a continuous structure that depends on the size of the surface being extruded and the height of the extrusion.

Cosmic Ray Sensors For The Continuous Measurement Of Arctic Snow Accumulation And Melt, Anton Jitnikovitch

Theses and Dissertations (Comprehensive)

In the Arctic, winter persists for much of the year, resulting in a hydrological system that is primarily regulated by snow and snowmelt runoff, and has important implications on vegetation, animals, and on the thermal regime of the active layer and permafrost. Snow water equivalent (SWE) measurements such as remote sensing techniques provide coarse resolution data, while snow surveys and snow-pits are labour intensive, have limited spatial coverage and do not provide a continuous reading. Over the last few decades, cosmic ray sensors (CRS) have been proposed as a way to provide much improved snow data, but few studies have …

High Resolution Spatial Variability In Spring Snowmelt For An Arctic Shrub-Tundra Watershed, Branden J. Walker, Philip Marsh Dr

Theses and Dissertations (Comprehensive)

Arctic tundra environments are characterized by spatially heterogeneous end-of-winter snow cover because of high winds that erode, transport and deposit snow over the winter. This spatially variable end-of-winter snow cover subsequently influences the spatial and temporal variability of snowmelt and results in a patchy snowcover over the melt period. Documenting changes in both snow cover area (SCA) and snow water equivalent (SWE) during the spring melt is essential for understanding hydrological systems, but the lack of high-resolution SCA and SWE datasets that accurately capture micro-scale changes are not commonly available, and do not exist for the Canadian Arctic. This study …

The Study Of Grit In Engineering Education Research: A Systematic Literature Review, Shannon Chance, Inês Direito, Manish Malik

Articles

Researchontheroleofgrit–definedasbothperseveranceandpassionfor long-termgoals–onhumanperformancehasbeenconductedforthepast decade. It has been suggested that this non-cognitive factor is a better predictor of students’ retention than traditional academic measures. These findings hold relevance for engineering education research but studies on this area are still scarce. This paper provides a systematic review of the current state of research on grit and its correlates in engineering higher education research. Publications were identified using three types of databases specific to engineering education; a final set of 31 relevant records was analysed by type of population, methods, research topics and main results. Most of the reviewed studies implemented quantitative methodologies to …

Use Of Matrix-Pencil Method For Efficient Islanding Detection In Static Dg And A Parallel Comparison With Dwt Method, Sanjay Agrawal, Sandipan Patra, Soumya R. Mohanty, Vineeta Agarwal, Malabika Basu

Articles

Islanding or nonislanding events in grid-connected distributed generation bring along a typical distinguishable transient signature in its frequency profile. This demarcation leads to the development of a new islanding protection approach, which is based on the estimation of frequency waveform parameter (transient's frequency) by Matrix pencil (MP) method. To demonstrate the efficacy of the proposed MP method, four critical scenarios are considered in this paper for covering all possible disturbance events. These events are also compared along with a discrete wavelet transform (DWT) based islanding detection method in simulations as well as in RT-LAB-based real-time environment. It is noteworthy to …

Improving Base Metal Electrowinning, Charles Ebenezer Abbey

Doctoral Dissertations

"In zinc electrowinning, Mn oxidizes to form MnO₂ on Pb-Ag anodes, cell walls and pipes. MnO₂ reduces anode corrosion but also leads to short circuits and maintenance issues. MnO₂ is thought to interact with chloride ions and produce oxidized chlorine species. The interactions between Mn and Cl are not well understood. Bench scale experiments were conducted to investigate the effects of the manganese to chloride ratio on anode corrosion rate and electrolyte chemistry using rolled Pb-Ag anodes. Increasing the average Mn/Cl^- ratio from ~7:1 to ~11:1 reduced the anode corrosion rate. Anode scales produced with Mn/Cl …

Time-Dependent Reliability Methodologies With Saddlepoint Approximation, Zhangli Hu

Doctoral Dissertations

"Engineers always encounter time-dependent uncertainties that ubiquitously exist, such as the random deterioration of material properties and time-variant loads. Therefore the reliability of engineering systems becomes time-dependent. It is crucial to predict the time-dependent reliability in the design stage, given possible catastrophic consequences of a failure. Although extensive research has been conducted on reliability analysis, estimating the reliability accurately and efficiently is still challenging. The objective of this work is to develop accurate and efficient reliability methodologies for engineering design. The basic idea is the integration of traditional reliability methods with saddlepoint approximation (SPA), which can accurately approximate the tail …

Modeling And Simulation Of Micro/Nano-Rod Distribution In Micro Channel Flows, Saman Monjezi

Doctoral Dissertations

"The behavior of a typical nanorod particle in microscale flows was theoretically investigated, considering the effect of the wall on the rotational and translation motions of the non-spherical particle. Initially, a systematic method using Brownian dynamics simulation of the rotational motion of nanorod was performed to obtain the average orientation distribution of a nanorod in various range of Peclet number and position from the confining wall. Subsequently, the results of the angle distributions simulation were employed to generate a universal mathematical model for the particle orientation distribution, which our model of concentration distribution of high aspect ratio nanorods in the …

Biofuel Supply Chain Restructuring -- An Economic Viability And Environmental Sustainability Investigation For Enhancing Second Generation Biofuel Adoption, Rajkamal Kesharwani

Doctoral Dissertations

"Biofuel is a promising clean alternative to fossil fuels. Currently, first generation biofuels are commercially produced by using corn grain as biomass feedstock. However, the use of edible matter of crops, may lead to a competition between food and fuel. Therefore, there is a significant push in both industry and academia to commercialize second generation biofuel manufacturing technology, which uses non-edible matter from crops. Most research focuses on individual manufacturing processes for producing second generation biofuel, but the economic and environmental impacts of a large-scale adoption of second generation biofuel manufacturing have been less widely reported.

This work investigates the …