Digital Commons Network^™

Measuring And Monitoring Speech Quality For Voice Over Ip With Polqa, Visqol And P.563, Andrew Hines, Eoin Gillen, Naomi Harte

Conference papers

There are many types of degradation which can occur in Voice over IP (VoIP) calls. Of interest in this work are degradations which occur independently of the codec, hardware or network in use. Specifically, their effect on the subjective and objec- tive quality of the speech is examined. Since no dataset suit- able for this purpose exists, a new dataset (TCD-VoIP) has been created and has been made publicly available. The dataset con- tains speech clips suffering from a range of common call qual- ity degradations, as well as a set of subjective opinion scores on the clips from 24 …

Dinitrogen Reduction On A Polypyrrole Coated Pt Electrode Under High-Pressure Conditions: Electrochemical Impedance Spectroscopy Studies, Di̇dem Balun Kayan, Fati̇h Köleli̇

Turkish Journal of Chemistry

The electrochemical impedance spectroscopy (EIS) responses of a polypyrrole (PPy)-coated platinum electrode were investigated during N$_{2}$-reduction to ammonia in aqueous medium. Kinetic parameters such as film resistance, pore resistance, and double layer capacitance were analyzed as a function of applied potential and polymer film thickness. The relation between kinetic parameters was discussed by combining electrolysis results. It was found that the optimum film thickness of polypyrrole was 0.73 $\mu $m and optimum potential for ammonia synthesis was -0.150 V under 60 bar N$_{2}$-pressure. The impedance responses under these conditions presented the lowest pore resistance value of ca. 2 $\Omega $ …

Green Synthesis Of 2-Amino-7-Hydroxy-4-Aryl-4$H$-Chromene-3-Carbonitriles Using Zno Nanoparticles Prepared With Mulberry Leaf Extract And Zncl$_{2}$, Akbar Mobinikhaledi, Atisa Yazdanipour, Majid Ghashang

Turkish Journal of Chemistry

A highly efficient and environmentally benign protocol for the synthesis of 2-amino-7-hydroxy-4-aryl-4$H$-chromene-3-carbonitrile derivatives in good to high yields (77%-97%) by one-pot three-component coupling reaction of aromatic aldehydes, malononitrile, and resorcinol under reflux condition was developed in aqueous media using ZnO nanoparticles that were prepared in the presence of mulberry leaf extract under mild conditions.

Designing Medical Interactive Systems Via Assessment Of Human Mental Workload, Luca Longo

Conference papers

In clinical settings, Human-computer systems need to be designed in a way that medical errors are reduced and patient care is enhanced. Inspection methods are usually employed in HCI to assess usability of interactive systems. However, they do not consider the state of the operator while executing a task, the surrounding environment and the task demands. It is argued that assessing performance of operators is fundamental for designing optimal systems with which healthcare can be effectively delivered. The aim of our solution is to assess performance of operators employing the notion of Mental Workload (MWL) this being a construct believed …

On The Relationship Between Perception Of Usability And Subjective Mental Workload Of Web Interfaces, Luca Longo, Pierpaolo Dondio

Conference papers

Inspection methods and cheap self-reporting procedures have been significantly employed in the field of Human- Computer Interaction for assessing the usability of interfaces, systems and technologies. However, there is a tendency to overlook aspects related to the context and features of the users during the usability assessment process. This research introduces the concept of mental workload as an aid to enhance usability measurement. A user-study has been designed and executed in the context of human-web interaction. The aim was to investigate the relationship between the perception of usability of three popular web-sites, and the mental workload imposed by a set …

Functional Gold Nanoparticle Coated Surfaces For Ca 125 Cancer Biomarker Detection, İlknur Tunç, Hepi̇ Hari̇ Susapto, Mustafa Özgür Güler

Turkish Journal of Chemistry

Here we describe the detailed characterization of gold nanoparticle (Au Np) functionalized surfaces as a biosensing platform by studying a model streptavidin (SA)-biotin interaction. Conjugation of SA on Au Np immobilized on silicon (Si) and quartz surfaces and its interaction with biotin were characterized by X-ray photoelectron spectroscopy (XPS), UV-Vis spectroscopy, circular dichromism (CD) spectroscopy, and contact angle measurements. The immobilization method and atomic concentrations of Si 2p, Au 4f, S 2p, C 1s, N 1s, and O 1s of the resulting SA-biotin modified Si surface were determined by XPS. The CD spectrum and confocal microscopy imaging confirmed that step-by-step …

Optimization Of The Adsorption Of A Textile Dye Onto Nanoclay Using A Central Composite Design, Aydin Hassani, Murat Kiranşan, Reza Darvishi Cheshmeh Soltani, Alireza Khataee, Semra Karaca

Turkish Journal of Chemistry

The main aim of this study was to evaluate the efficacy of montmorillonite clay for the adsorption of C.I. Basic Yellow 2 (BY2) dye from aqueous media. The experimental results were processed by response surface methodology based on a central composite design (CCD). The effect of four main variables, including initial BY2 concentration, adsorbent dosage, reaction time, and temperature on the removal of BY2 was evaluated by the model. The accuracy of the model and regression coefficients was appraised by employing analysis of variance. The results demonstrated a good agreement between the predicted values obtained by the model and the …

Synthesis Of Metal-Free And Metallophthalocyanines Containing 18- And 21-Membered Macrocycles With Mixed Donor Atoms And Their Metal-Ion Binding Properties, Hali̇l Zeki̇ Gök

Turkish Journal of Chemistry

This paper describes the synthesis of a series of metal-free phthalocyanines and metallophthalocyanines peripherally substituted by macrocycles of different ring sizes with the same donor atom sets. The effects of varying ring size of the macrocycle on the spectroscopic and metal ion binding properties of phthalocyanines were examined. For these purposes, electronic absorption properties for metal-free phthalocyanines and metallophthalocyanines were studied in dimethylformamide and tetrahydrofuran. The liquid-liquid extraction of metal picrates such as Ag(I), Hg(II), Cd(II), Zn(II), Cu(II), Ni(II), Pb(II), and Co(II) from the aqueous phase to the organic phase was carried out using metallophthalocyanines. All new compounds were characterized …

Purification, Refolding, And Characterization Of Recombinant Human Paraoxonase-1, Yeli̇z Demi̇r, Şükrü Beydemi̇r

Turkish Journal of Chemistry

A high density lipoprotein (HDL)-linked enzyme with antioxidant and antiatherogenic properties, paraoxonase-1(PON1), prevents the formation of atherosclerotic lesions in humans. In the present study, a recombinant hPON1 gene was produced using a small ubiquitin-related modifier (SUMO) fusion protein expression system. To that end, the hPON1 gene was amplified from human liver-ready cDNA, cloned into the expression vector pET SUMO, and expressed in Escherichia coli BL21 (DE3). The predominance of the expressed fusion SUMO-hPON1 protein was inclusion bodies and purified using 6xHis affinity chromatography under natural and denaturing conditions. Subsequently, the enzyme was purified and refolded directly on the affinity matrix …

Synthesis And Characterization Of Novel Urea And Thiourea Substitute Cyclotriphosphazene Compounds As Naked-Eye Sensors For F$^{-}$ And Cn$^{-}$ Anions, Hava Özay, Mehmet Yildirim, Özgür Özay

Turkish Journal of Chemistry

Novel hexakisurea and thiourea cyclotriphosphazene compounds (3-7) were synthesized. The structure of all compounds was identified using FT-IR $^{1}$H, $^{13}$C, and $^{31}$P NMR spectroscopy; MALDI-TOF MS; and elemental analysis. The optical sensor properties for anions of 3-7 were investigated using UV-Vis spectroscopy. It was determined that compounds 6 and 7 are spectrophotometric and naked eye sensors for F$^{-}$ and CN$^{-}$ anions, respectively. Sensor properties of these compounds for anions were investigated using UV-Vis spectroscopy. The stoichiometry of host-guest complexes was found to be 1:6.

Microwave-Assisted Regioselective [1,3]-Dipolar Cycloaddition Of 3-Methyl-2-(Substitutedbenzylidene)-5-Oxopyrazolidin-2-Ium-1-Ides To Benzothiophene 1,1-Dioxide, Yaşar Dürüst, Eda Sağirli, Akin Sağirli

Turkish Journal of Chemistry

A series of pyrazolidinium ylides was reacted with benzothiophene 1,1-dioxide to afford (3R,5S,5aS,10bS)-3-methyl-5-substitutedphenyl-2,3,5,5a-tetrahydrobenzo[4,5]thieno[3,2-c]pyrazolo[1,2-a]pyrazol-1(10bH)-one 6,6-dioxides under microwave irradiation and their structures were identified by means of spectral/physical characteristics including X-ray diffraction data and HRMS measurements.

A Case Study On In Vitro Investigations Of The Potent Biological Activities Of Wheat Germ And Black Cumin Seed Oil, Di̇dem Ağ Şeleci̇, Zi̇nar Pinar Gümüş, Murat Yavuz, Muharrem Şeleci̇, Rebecca Bongartz, Frank Stahl, Hakan Coşkunol, Suna Ti̇mur, Thomas Scheper

Turkish Journal of Chemistry

The objectives of this study were to investigate the potential biological activities of black cumin seed oil (BCSO) and wheat germ oil (WGO) on different cell lines. Initially, commercially available BCSO and WGO obtained by supercritical carbon dioxide extraction were analyzed in terms of tocopherol, aliphatic alcohols, and thymoquinone content via HPLC and GC analysis. Cell free antioxidant activities and total phenolic content of both oils were detected by DPPH assay and Folin-Ciocalteu method, respectively. As well as the DPPH assay, the protective effect against reactive oxygen species (ROS) was determined by microscopic observation of ROS generation in NIH-3T3 cells …

Enhanced Electrocatalytic Efficiency Of C/Mwnts For Methanol Oxidation Using Ni Deposited On Mwnts, Murat Farsak, Gülfeza Kardaş

Turkish Journal of Chemistry

The power density of direct methanol fuel cells (DMFCs) can be changed by using different anode materials. Especially porous materials are preferred for the anode. In the present study, multiwall carbon nanotubes were first injected into graphite. Then, by depositing nickel, a catalyst was prepared for use as the anode material of the DMFC. This catalyst was named Ni@MWNTs. The oxidation of methanol and some kinetic parameters were investigated in KOH solution. Cyclic voltammetry was used for the electrochemical measurements. Kinetic parameters of the methanol oxidation were determined at different temperatures, scan rates, and concentrations of methanol. The surface morphologies …

Conversion Of Racemic Allylic Hydroperoxides Into Corresponding Chiral 1/2,3-Triols By Using Catalytic Oso$_{4}$ And Chiral Cinchona Ligands In The Absence Of Co-Oxidant, Haydar Göksu, Mehmet Serdar Gülteki̇n

Turkish Journal of Chemistry

For the first time, removal of oxygen atoms from allylic hydroperoxide functionality and reintroduction to the double bond was achieved using catalytic OsO$_{4}$ and chiral cinchona alkaloid derivatives in an acetone-water mixture to give corresponding chiral 1/2,3-triol with an enantioselectivity up to 99% ee. The hydroperoxide group was used as both a co-oxidant and a source of hydroxyl groups. This protocol is thought to have potential to provide opportunities for chiral synthesis of 1/2,3-triols from corresponding allylic hydroperoxides in the absence of co-oxidant in one stage for the first time in the literature.

Microwave-Assisted Synthesis Of Novel 8-Chloro-[1,2,4]Triazolo[4,3-$A$]Pyridine Derivatives, Linjiong Zhang, Mingyan Yang, Beizhen Hu, Zhaohui Sun, Xinghai Liu, Jianquan Weng, Chengxia Tan

Turkish Journal of Chemistry

A series of novel 1,2,4-triazolo[4,3-$a$]pyridine derivatives were synthesized from 2,3-dichloropyridine and hydrazine hydrate as starting materials by multistep reactions under microwave assistance, and their structures were characterized by $^{1}$H NMR, MS, and elemental analysis. This method provides several advantages such as high yields, facile work-up, and environmental friendliness.

Synthesis Of 5-Aryl-$N$-(Trichloroacetyl)-1,3,4-Oxadiazole-2-Carboxamide Via Three-Component Reaction Of Trichloroacetyl Isocyanate, ($N$-Isocyanimino)Triphenylphosphorane, And Benzoic Acid Derivatives, Nahid Shajari, Ali Reza Kazemizadeh, Ali Ramazani

Turkish Journal of Chemistry

The three-component reaction of benzoic acid derivatives, ($N$-isocyanimino)triphenylphosphorane, and trichloroacetyl isocyanate in a 1:1:1 ratio in CH$_{3}$CN occurred at room temperature, and the 5-aryl-$N$-(trichloroacetyl)-1,3,4-oxadiazole-2-carboxamide derivatives produced were formed in high yields. The reaction proceeded smoothly and cleanly under mild reaction conditions and no side reactions were observed. The structures of the products were confirmed by IR, $^{1}$H NMR, $^{13}$C NMR, mass spectroscopy, and elemental analysis.

Microwave-Assisted Synthesis Of Condensed 1,4-Dihydropyridines As Potential Calcium Channel Modulators, Erdem Kami̇l Özer, Mi̇yase Gözde Gündüz, Ahmed El-Khouly, Mehmet Yildirim Sara, Rahi̇me Şi̇mşek, Alper Bektaş İski̇t, Osman Ci̇hat Şafak

Turkish Journal of Chemistry

This study reports the design, synthesis, and calcium channel modulatory activity evaluation of a series of 14 novel fused 1,4-dihydropyridine derivatives. The molecular design of the compounds was based on modifications of nifedipine, which is a calcium channel blocker. The compounds were achieved by one-pot microwave-assisted reaction of 4,4-dimethyl-1,3-cyclohexanedione, 5-chlorosalicylaldehyde/3,5-dichlorosalicylaldehyde, an appropriate alkyl acetoacetate, and ammonium acetate in ethanol according to a modified Hantzsch reaction. The structures of the compounds were confirmed by spectral methods and elemental analysis. To evaluate their relaxant activities, the maximum relaxant response (E$_{\max})$ and pD$_{2}$ values of the compounds and nifedipine were determined on isolated …

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

A Comparative Study On Fabrication Of Cu$_{2}$Znsns$_{4}$ (Czts) Nanofibers Using Acetate And Chloride Metal Precursors, Burak Zafer Büyükbekar, Faruk Özel, Hüseyi̇n Şakalak, Hali̇t Çavuşoğlu, Mustafa Ersöz, Mahmut Kuş, Mustafa Selman Yavuz

Turkish Journal of Chemistry

This study reports, for the first time, the fabrication of electrospun Cu$_{2}$ZnSnS$_{4}$ (CZTS) nanofibers using metal acetate precursors. Viscous poly(vinyl pyrrolidone) (PVP) solution containing acetate or chloride salts of copper, zinc, and tin was electrospun onto a conductive substrate. The PVP nanofibers that have a mixture of metal salts were annealed at elevated temperatures. After calcination, these nanofibers were treated with the sulfur source and then annealed again in order to generate CZTS nanofibers. The CZTS nanofibers generated from acetate and chloride salts were characterized and compared. Belt-like and wire-like nanofibers were obtained when using metal acetate and chloride precursors, …

A New Series Of Cu(Ii) And Ni(Ii) Complexes Of No Bidentate 4-No$_{2}$-Benzoylhydrazones: Synthesis, Characterization, And Biological Studies, Hati̇ce Başpinar Küçük, Emel Mataraci Kara, Berna Özbek Çeli̇k

Turkish Journal of Chemistry

A series of new nickel(II) and copper(II) hydrazone complexes \textbf{1--14}, containing a bidentate NO-donor hydrazone ligand, derived from 4-nitrobenzoylhydrazide and several aliphatic and aromatic aldehydes were synthesized, and their chemical structures were confirmed by means of FT-IR, UV-Vis, $^{1}$H and $^{13}$C NMR, mass spectral data, conductance measurements, and elemental analyses. The spectral data of the newly synthesized complexes show the formation of a 1:2 [metal:ligand] ratio. The ligands and their complexes were also investigated for their possible in vitro antimicrobial activities against \textit{S. aureus}, \textit{S. epidermidis}, \textit{E. coli}, \textit{K. pneumonia}, \textit{P. aeruginosa}, \textit{P. mirabilis}, \textit{E. faecalis}, and \textit{C. albicans}. Among …

Effective Recognition Of Multiple Anions By An Azobenzene--Al$^{\Mathbf{3+}}$ System, Ye Zhang, Ping Jia, Zhangfa Tong, Hai-Bo Liu, Jing Wang

Turkish Journal of Chemistry

A ready-to-use multifunctional coordinative system, 2,2'-dihydroxyazobenzene --aluminum (III) (DHAB--Al$^{3+})$, was created to recognize several anions effectively through three channels, namely colorimetric detection, UV-Vis spectroscopy, and fluorescence spectroscopy. Under naked eye visualization, the H$_{2}$PO$_{4}^{-}$ can be readily distinguished from the other anions by the DHAB--Al$^{3+}$ system through a change in color from reddish-orange to light yellow. H$_{2}$PO$_{4}^{-}$ was qualitatively detected by using UV-Vis and fluorescence spectra. Differentiating SO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ anions colorimetrically is difficult; thus, CO$_{3}^{2-}$, SO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ were discriminated by adopting distinct changes in the UV-Vis spectra. CO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ were accurately quantified using fluorescence spectra. …

Synthesis, Characterization, And Electrical And Optical Properties Of Magnesium-Type Boracite, Tuğba İbroşka, Azmi̇ Seyhun Kipçak, Süreyya Aydin Yüksel, Emek Derun, Sabri̇ye Pi̇şki̇n

Turkish Journal of Chemistry

Synthesis of the magnesium type of the mineral boracite (Mg$_{3}$B$_{7}$O$_{13}$Cl) was studied. Several parameters affecting boracite synthesis were investigated. The raw materials selected were magnesium chloride hexahydrate (MgCl$_{2}$.6H$_{2}$O), magnesium oxide (MgO), and boron oxide (B$_{2}$O$_{3})$. Reaction temperatures were selected between 600~$^{\circ}$C and 900 $^{\circ}$C. Moreover, three different reaction times of 4, 1, and 0.5 h were studied with the determined optimum molar ratio, reaction temperature, and reaction medium. Synthesized boracite characterization analyses were done by the techniques of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscope (SEM). Reaction yields were also calculated. From the results of …

Separation And Preconcentration Of Lead(Ii), Cobalt(Ii), And Nickel(Ii) On Edta Immobilized Activated Carbon Cloth Prior To Flame Atomic Absorption Spectrometric Determination In Environmental Samples, Zeid Abdullah Alothman, Erkan Yilmaz, Mohamed Habi̇la, Mustafa Soylak

Turkish Journal of Chemistry

The synthesis and characterization of ethylenediaminetetraacetic acid immobilized activated carbon cloth was performed in the present work. It was used for preconcentration-separation of lead(II), cobalt(II), and nickel(II) at trace levels as an adsorbent. Factors including pH, concentration and volume of eluent, sample and eluent flow rates, sample volume, and effect of coexisting ions on the solid phase extraction of analytes were examined. The preconcentration factor was 50. The detection limits for Pb(II), Co(II), and Ni(II) were 4.39, 0.99 and 0.91 $\mu $g L$^{-1}$, respectively. The adsorption capacity for Pb(II), Co(II), and Ni(II) ions was found as 11.0, 11.2, and 10.2 …

Properties And Some In Vitro Studies Of 6-Phosphogluconate Dehydrogenase Purified From The Liver Of Chalcalburnus Tarichi, The Only Fish Living In Lake Van's Highly Alkaline Water (Ph 9.8), Muhammet Güler, Vedat Türkoğlu, Mehmet Riza Kivanç

Turkish Journal of Chemistry

In this study, some enzymology parameters and some antibiotics affecting the enzyme activity of 6-phosphogluconate dehydrogenase (6PGD) extracted from t the livers of fish from Lake Van (\textit{Chalcalburnus tarichi}) were investigated because it is an important enzyme-producing NADPH, a reductive power, protecting the cell against the oxidative agents by producing reduced glutathione. The crude enzyme solution was obtained by using the affinity chromatography method. The native molecular weight of the enzyme is $\sim $90,000 $\pm $ 3000 Da and it is composed of two subunits with identical molecular weights of $\sim $46,000 Da as exhibited on sodium dodecyl sulfate-polyacrylamide gel …

Green And Efficient Synthesis Of Novel Bispyrazoles Through A Tandem Knoevenagel And Michael Type Reaction Using Nanowire Zinc Oxide As A Powerful And Recyclable Catalyst, Khalil Eskandari, Bahador Karami, Saeed Khodabakhshi, Seyyed Jafar Hoseini

Turkish Journal of Chemistry

Zinc oxide nanowires (ZnO NWs) were prepared and characterized by scanning electron microscopy, powder X-ray diffraction, and transmission electron microscopy analyses. ZnO NWs were then employed as heterogeneous and recyclable catalyst for green synthesis of some new and known bispyrazole derivatives through a tandem Knoevenagel and Michael type addition reaction of aromatic aldehyde and pyrazolone. The synthetic method is operationally simple and affords product with high yields in short reaction times.

Corrosion Inhibition By Naturally Occurring Hibiscus Sabdariffa Plant Extract On A Mild Steel Alloy In Hcl Solution, Magda Abdo Mahmoud Ameer, Amany Mohamed Fekry

Turkish Journal of Chemistry

The corrosion inhibition of mild steel alloys is of tremendous technological importance due to their increased industrial applications. Potentiodynamic polarization and electrochemical impedance spectroscopy techniques were used to establish the effect of different concentrations of HCl on the corrosion behavior of mild steel. A study was conducted on the inhibition of dissolution for a mild steel alloy in the most corrosive concentration of HCl (5 M) by adding different concentrations of aqueous extract of \textit{Hibiscus sabdariffa} plant (named karkade or rosselle) as an ecofriendly inhibitor. The extent of corrosion inhibition as measured by the two techniques was comparable. The results …

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

Cross Coupling Reactions Catalyzed By (Nhc)Pd(Ii) Complexes, Nevi̇n Gürbüz, Emi̇ne Özge Karaca, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

This review is focused on new developments reported during the last 3 years concerning the catalytic performances of in situ formed or preformed NHC--Pd(II) complexes (NHC: $N$-heterocyclic carbene) for cross-coupling reactions such as Heck--Mizoraki (often shortened to the Heck reaction), Kumada, Negishi, Suzuki--Miyaura (often shortened to the Suzuki reaction), Sonogashira and Hiyama couplings, and the Buchwald--Hartwig aminations, which are extremely powerful in the formation of C--C and C--heteroatom bonds. Due to the great number of publications and limited space here, we made a special attempt to compile the relevant data in tables, which we hope will serve as a guide …

Theatre Safety In Louisiana Secondary Schools: A Survey Study, Christopher Pyfrom

LSU Master's Theses

Participation in secondary school theatre can have many benefits including the development of improved reading comprehension, self-concept, and empathy. In the world of professional theatre, each design area has its own department head and several levels of assistants and workers below them. Yet in the world of secondary school theatre, we expect one person to assume all of those roles in addition to the regular responsibilities of teaching. Not many people see theatre as being dangerous when compared to sports, science labs, or vocational education. However, it can contain many of the same risks. This study investigated several factors that …

Relativistic Configuration Interaction Calculations Of The Atomic Properties Of Selected Transition Metal Positive Ions; Ni Ii, V Ii And W Ii, Marwa Hefny Abdalmoneam

Dissertations, Master's Theses and Master's Reports

Relativistic Configuration Interaction (RCI) method has been used to investigate atomic properties of the singly ionized transition metals including Nickel (Ni II), Vanadium (V II), and Tungsten (W II). The methodology of RCI computations was also improved. Specifically, the method to shift the energy diagonal matrix of the reference configurations was modified which facilitated including the effects of many electronic configurations that used to be difficult to be included in the energy matrix and speeded-up the final calculations of the bound and continuum energy spectrum. RCI results were obtained for three different cases:

1. Atomic moments and polarizabilities of Ni II; …