Digital Commons Network^™

Synthesis Of Novel Chiral Bisoxazoline Ligands With A Norbornadiene Backbone: Use In The Copper-Catalyzed Enantioselective Henry Reaction, Rabi̇a Deli̇kuş, Emi̇ne Çakir, Nadi̇r Demi̇rel, Meti̇n Balci, Betül Karataş

Turkish Journal of Chemistry

Novel chiral bisoxazoline ligands based on norbornadiene were synthesized and used for the asymmetric Henry reaction. Various aromatic aldehydes were converted into chiral $\beta $-nitro alcohols with high yields and moderate to acceptable enantioselectivities under the optimized reaction conditions.

The Role Of N-Heterocyclic Carbene Substituents On Ruthenium(Ii) Complexes In The Catalytic Transfer Hydrogenation Of Acetophenone, Muhammet Emi̇n Günay, Gülcan Gençay Çoğaşlioğlu

Turkish Journal of Chemistry

The novel ruthenium(II) complexes [RuCl$_{2}$(NHC)($p$-cymene)], \textbf{3a}--\textbf{e}, containing 1-alkyl-3-benzylimidazol-2-ylidene ligands were prepared. All synthesized compounds were characterized by NMR spectroscopy and elemental analyses. Ru(II)-NHC complexes were tested as catalysts for the transfer hydrogenation of acetophenone, showing modest to high activity in this reaction. The results revealed that efficiencies depend on the substituents of the benzene ring of the benzyl on the N atom of the NHC ring.

Oxidative Dehydrogenation Of Propane Over V$_{2}$O$_{5}$ And K$_{2}$O-V$_{2}$O$_{5}$ Impregnated Mgal$_{2}$O$_{4}$Catalysts, Serkan Naci̇ Koç, Kübra Dayioğlu, Hasan Özdemi̇r

Turkish Journal of Chemistry

V$_{2}$O$_{5}$ and K$_{2}$O-V$_{2}$O$_{5}$ impregnated MgAl$_{2}$O$_{4}$ catalysts were prepared and tested for the oxidative dehydrogenation of propane. The as-synthesized catalysts were characterized by using the XRD, BET, NH$_{3}$-TPD, TPR, and XPS methods. The catalytic tests were performed in a fixed bed tubular quartz reactor system between 450 and 550 $^{\circ}$C. It was observed that the conversion of propane increased but hydrocarbon selectivity decreased with increasing temperature over the V$_{2}$O$_{5}$/MgAl$_{2}$O$_{4}$ catalysts. The BET surface area values and surface acidities decreased upon potassium addition for the K-V$_{2}$O$_{5}$/MgAl$_{2}$O$_{4}$ catalysts, which resulted in a drastic drop in the conversion values obtained. The propylene and total …

Synthesis Of Graft Copolymer Of Kappa-Carrageenan Using Microwave Energy And Studies Of Swelling Capacity, Flocculation Properties, And Preliminary Acute Toxicity, Tapan Kumar Giri, Minakshi Pradhan, Dulal Krishna Tripathi

Turkish Journal of Chemistry

Grafting of acrylamide (AAm) onto kappa-carrageenan (KC) was carried out using microwave irradiation in the presence of ammonium persulfate (APS) as initiator. The effect of reaction variables including the concentration of APS, AAm, and KC; time duration; and microwave power was studied. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM) were carried out to characterize the graft copolymer. The graft copolymer possesses slightly sensitive activities to external pH and shows reversible on--off switching swelling characteristics. Flocculation efficacy of the graft copolymer was studied in coal fine suspension toward potential application as …

Impregnation Of Different Ionic Liquids Onto Cationic Starch And Their Comparison In The Extraction Of Th(Iv), Eli̇f Ant Bursali, Serap Seyhan Bozkurt, Mürüvvet Yurdakoç

Turkish Journal of Chemistry

Cationic starch (CS) was prepared by using epichlorohydrin (EPI) and 3-chloro-2-hydroxypropyltrimethy- lammonium chloride (CHPTMA) and ionic liquids (ILs) having different anionic groups [1-butyl-3-methyl imidazolium tetrafluoroborate (BMI$^{+}$BF$_{4}^{-})$, 1-butyl-3-methyl imidazolium bromide (BMI$^{+}$Br$^{-})$, 1-butyl-3-methyl imidazolium hexafluorophosphate (BMI$^{+}$PF$_{6}^{-})$, and 1-butyl-3-methyl imidazolium bis-[(trifluoromethyl)sulfonyl]imide (BMI$^{+}$ [(TF)$_{2}$N]$^{-})$] were impregnated onto CS. Thorium(IV) ions were preconcentrated by using IL impregnated CS. The effects of ILs were investigated for extraction of Th(IV) by CS and the results were compared. Th(IV) was preconcentrated with approximately 73{\%} sorption capacity by CS and increased up to 98{\%}--100{\%} for IL impregnated sorbents at pH 7.0. The sorption capacities of Th(IV) were 0.453 mmol …

Synthesis And Evaluation Of Some Novel Thiazoles And 1,3-Thiazines As Potent Agents Against The Rabies Virus, Magda Abdalla, Sobhi Gomha, Mohamad Abd Elaziz, Nany Serag

Turkish Journal of Chemistry

A series of novel thiazoles and 1,3-thiazine derivatives were synthesized in good yield via reaction of ethyl 3-(1-(2-thiocarbamoylhydrazono)ethyl)-1,5-diphenyl-1$H$-pyrazole-4-carboxylate with hydrazonoyl halides and arylidenemalononitriles, respectively. The structure of the newly synthesized products was elucidated via elemental analysis, spectral data, and alternative routes whenever possible. Moreover, the antiviral screening of the products was evaluated and the results revealed that some of them have strong to moderate potency against the rabies virus compared with the reference drug.

Co$_{2}$ Adsorption Behavior And Kinetics On Chemically Modified Activated Carbons, Burcu Selen Çağlayan, Ahmet Erhan Aksoylu

Turkish Journal of Chemistry

CO$_{2}$ adsorption capacities of activated carbon-based adsorbents subjected to different treatments, such as HNO$_{3}$ oxidation, air oxidation, alkali impregnation, and heat treatment under helium gas atmosphere, were determined by gravimetric analyses and reported previously by our group. In the current work, the experimental adsorption isotherms of these modified activated carbon samples were fitted to Langmuir, Freundlich, and Dubinin--Radushkevich (D-R) models. The best fits were obtained to the D-R equation, indicating competitive or multilayer CO$_{2}$ adsorption occurring in the micropores of the adsorbents. Air oxidation followed by alkali impregnation led to the highest micropore volume, ranging between 0.259 and 0.298 g.CO$_{2}$/g.adsorbent, …

Zr(Iv), Ti(Iv), And V(Iii) Complexes Of Some Benzimidazole, Benzothiazole, And Benzoxazole Ligands: Characterization And Catalyst Efficiency In Ethylene Polymerization, Hamdi Ali Elagab, Helmut G. Alt

Turkish Journal of Chemistry

Fifteen complexes of 2, 2-bis- (benzimidazole, benzothiazole, and benzoxazole) compounds with Zr(IV), Ti(IV), and V(III) metal centers were synthesized, characterized, activated with methyalumoxane (MAO), and then tested for catalytic ethylene polymerization. The activities of the various catalysts were found to be functions of the hetero atoms in the ligand frameworks. The activity of the catalyst system \textbf{6}/MAO was found to be 1372 kg PE/mol cat. h. The polyethylene produced with the catalyst system 6/MAO showed high molecular weights (1.84 $\times $ 10$^{6}$ g/mol) and broad molecular weight distributions (PD = 11). This could result from different interactions of the MAO …

Synthesis, Reaction, And Evaluation Of The Anticancer Activity Of 6,7,8,9-Tetrahydro-5$H$-Cyclohepta[4,5]Selenopheno[2,3-$D$]Pyrimidine Derivatives, Kadi̇r Doğanay, Ünzi̇le Keleştemur, Sevgi̇ Balcioğlu, Burhan Ateş, Ali̇ye Altundaş

Turkish Journal of Chemistry

The cyclocondensation of 2-amino-5,6,7,8-tetrahydro-4$H$-cyclohepta[$b$] selenophene-3-carbonitrile (1) with formic acid and formamide gave the selenophenopyrimidine 15 and selenophenopyrimidone 6 derivatives. The reaction of 6 with phosphorus oxychloride produced 4-chloro-6,7,8,9-tetrahydro-5$H$-cyclohepta[4,5] seleno[2,3-$d$]pyrimidine (12), the key compound for our nucleophilic substitution reactions. The hydrazinoselenophenopyrimidine 19 obtained from the reaction of 12 with hydrazine hydrate was converted to its tetrazoloselenophenopyrimidine 21 and triazoloselenophenopyrimidine 26 derivatives. Moreover, the chloropyrimidine derivative was reacted with pyrrolidine and morpholine to afford 4-(1-pyrrolidinyl)-6,7,8,9-tetrahydro-5$H$-cylohepta[4,5]selenopheno[2,3-$d$]pyrimidine (27) and 4-(6,7,8,9-tetrahydro-5$H$-cyclohepta[4,5]selenopheno[2,3-$d$]pirimidin-4-yl)morpholine (28). Anticancer activities of the synthesized compounds were investigated against the MCF-7 breast cancer cell line and the IC$_{50}$ values of these compounds were …

Experimental And Theoretical Investigation Of The Reaction Between Co$_{2}$ And Carbon Dioxide Binding Organic Liquids, Hi̇lal Tankal, Özge Yüksel Orhan, Erdoğan Alper, Telhat Özdoğan, Hakan Kayi

Turkish Journal of Chemistry

The reaction kinetics of CO$_{2}$ absorption into new carbon dioxide binding organic liquids (CO$_{2}$BOLs) was comprehensively studied to evaluate their potential for CO$_{2}$ removal. A stopped-flow apparatus with conductivity detection was used to determine the CO$_{2}$ absorption kinetics of novel CO$_{2}$BOLs composed of DBN (1,5-diazabicyclo[4.3.0]non-5-ene)/1-propanol and TBD (1,5,7-triazabicyclo[4.4.0]dec-5-ene)/1-butanol. A modified termolecular reaction mechanism for the reaction of CO$_{2}$ with CO$_{2}$BOLs was used to calculate the observed pseudo-first-order rate constant k$_{0}$ (s$^{-1})$ and second-order reaction rate constant k$_{2}$ (m$^{3}$/kmol.s). Experiments were performed by varying organic base (DBN or TBD) weight percentage in alcohol medium for a temperature range of 288-308 K. …

Adsorption Of Cellulase On Poly(2-Hydroxyethyl Methacrylate) Cryogels Containing Phenylalanine, Murat Yavuz, Oğuz Çakir, Zübeyde Baysal

Turkish Journal of Chemistry

The aim of this study was to prepare a supermacroporous cryogel that can be used for the adsorption of cellulase. The macroporous cryogel of poly(2-hydroxyethyl methacrylate-N-methacryloyl-l-phenylalanine) [p(HEMA-MAPA)] was prepared by copolymerization of 2-hydroxyethyl methacrylate (HEMA) with a functional monomer of N-methacryloyl-l-phenylalanine (MAPA). The cryogel was characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and swelling tests. The effects of several parameters such as medium pH, temperature, ionic strength, and flow rate on cellulase adsorption were also investigated. Maximum cellulase adsorption was observed at 25 $^{\circ}$C and pH 4.0. Furthermore, adsorbed cellulase was desorbed from the cryogel by using 1.0 …

Electrochemical Investigation Of2-[8-Hydroxyquinoline-5-Yl)Azo]Benzo[$C$]Cinnoline On A Platinum Electrode In Dimethysulfoxide, Funda Öztürk, Zehra Yazan, Oznur Olmez, Emi̇ne Kiliç, Esma Kiliç

Turkish Journal of Chemistry

2-[8-hydroxyquinoline-5-yl)azo]benzo[c]cinnoline was synthesized for the first time and shown to possess electrochromic characteristic, i.e. changing color during the forward and back electrolysis at --1.35 V and 0.00 V, respectively, in DMSO medium. Therefore, the electrochemical investigation of this compound appears to be worthwhile. The electrochemical reduction of 2-[8-hydroxyquinoline-5-yl)azo]benzo[c]cinnoline was investigated by cyclic voltammetry, controlled potential electrolysis, and chronoamperometry techniques in the presence of 0.10 mol L$^{-1}$ tetrabutylammonium tetrafluoroborate in dimethyl sulfoxide at platinum electrode. 2-[8-Hydroxyquinoline-5-yl)azo]benzo[c] cinnoline displays three sharp cathodic peaks and three anodic peaks in the cyclic voltammogram. The diffusion coefficients and the number of electrons transferred were calculated …

Degradation Of Bisphenol-A Using A Sonophoto Fenton-Like Hybrid Process Over A Lafeo$_{3}$ Perovskite Catalyst And A Comparison Of Its Activity With That Of A Tio$_{2}$ Photocatalyst, Meral Dükkanci

Turkish Journal of Chemistry

Oxidation of bisphenol-A (BPA) was investigated using a sonophoto Fenton-like hybrid process under visible light irradiation in the presence of iron-containing perovskite LaFeO$_{3}$ catalysts. For this purpose, firstly the perovskite catalyst (LaFeO$_{3})$ was prepared by the sol-gel method and calcined at different temperatures (500, 700, and 800 $^{\circ}$C). The prepared catalysts were characterized using XRD, SEM, FTIR, nitrogen adsorption, UV-vis DRS, and ICP/OES measurements. Among the prepared catalysts the catalyst that was calcined at 500 $^{\circ}$C showed better catalytic activity with respect to degradation and chemical oxygen demand (COD) reduction (of 21.8% and 11.2%, respectively, after 3 h of reaction …

Latest Trends, Green Aspects, And Innovations In Liquid-Phase--Based Microextraction Techniques: A Review, Erkan Yilmaz, Mustafa Soylak

Turkish Journal of Chemistry

Liquid-phase microextraction (LPME) methods including single-drop microextraction (SDME), hollow-fiber LPME (HF-LPME), and dispersive liquid-liquid microextraction (DLLME) have in the very short time since their invention grabbed the attention of scientists. Up to now, LPME methods have shown important innovations for the extraction and preconcentration of both inorganic and organic trace analytes from different matrices. These LPME methods offer unique advantages such as high preconcentration factor for target analytes in a single step, low cost, simplicity, excellent preconcentration capability, sample cleanup and integration of steps, and combined use with almost every analytical measurement technique. We describe the milestones and the combined …

Chromium Redox Speciation In Food Samples, Krystyna Pyrzynska

Turkish Journal of Chemistry

Chromium is an element with important biological characteristics, depending on its different species. Cr(III) is considered as essential; however, the Cr(VI) form is classified as carcinogenic.~For this reason, speciation analysis in food samples is a very important question. The proposed data procedures for chromium redox speciation in the literature can be divided into those with the use of online hyphenated techniques and those where appropriate sample pretreatment is necessary. The strategies for nonchromatographic speciation are mainly based on selective liquid--liquid extraction procedures, coprecipitation, selective separation of chromium species using a solid phase extraction column, or complexation reactions. In this paper, …

Small Business Survivability Beyond Five Years, Koyandome Freddy Koyagialo

Walden Dissertations and Doctoral Studies

The United States has a high failure rate of small businesses, with 30% of small business failing within the first 2 years. The objective of this case study was to explore strategies successful small business owners use to achieve profitability beyond 5 years. The purposive sample for this study included 4 owners of successful small businesses in Atlanta, Georgia, who have been in business for at least 5 years. The conceptual framework was built upon disruptive innovation and susceptibility theory. Data were collected through semistructured interviews and company documents. The analysis revealed 3 themes, market research, passion and determination, and …

Using The Wais-Iv To Detect Malingering, Thomas E. Bybee

Walden Dissertations and Doctoral Studies

This study used subtests of the WAIS-IV to detect evidence of malingering. Developing reliable tests for malingering could significantly reduce costs paid to malingering individuals. A within-group known-group design was used. There were 3 known-group conditions. The first group (G1) was instructed to take the tests honestly. The second group (G2) was asked to fake a cognitive disability while taking the tests. The third group (G3) took the tests while undergoing the cold-pressor method (hand immersed in cold water) of inducing pain. Analysis of variance was performed. That analysis appeared to have significant differences; post hock Bonferroni testing was done. …

Understanding The Relationships Among Students' Goal Orientations, Self-Efficacy, Anxiety, And Accelerated Academic Success In The Redesign Of Developmental Mathematics, Kelly Ann Hogan

Walden Dissertations and Doctoral Studies

The low success rates of increasing numbers of underprepared students taking developmental mathematics classes 'often minority and economically disadvantaged' are challenging community colleges across the United States. These students, who must start in the lowest levels of precollege mathematics courses, are unlikely to pass the first course and earn a credential. Using a mastery goal orientation theoretical framework, a quantitative, survey research design was used to ascertain any correlations between students' goal orientations, self-efficacy, test anxiety, and success in a new model of learning. Survey data were used to answer 3 research questions: (a) the relationship between success and students' …

A Quantitative Quasi-Experimental Study Of An Online High School Mathematics Remediation Program, Terry Meehan

Walden Dissertations and Doctoral Studies

The local problem that drove this study is that a high school in an upper middle class suburban city in Pennsylvania wants to improve its student scores on its end-of-course Algebra 1 Keystone Exam. The purpose of this study was to conduct a quantitative, quasi-experimental assessment of an online high school mathematics remediation program to determine if the remediation program was successful in its endeavor to remediate students. This research study, informed by the self-efficacy and the behaviorist learning theories, attempted to determine whether students who (a) scored below proficient on the May algebra exam and were placed in the …

Examining Data Privacy Breaches In Healthcare, Tanshanika Turner Smith

Walden Dissertations and Doctoral Studies

Healthcare data can contain sensitive, personal, and confidential information that should remain secure. Despite the efforts to protect patient data, security breaches occur and may result in fraud, identity theft, and other damages. Grounded in the theoretical backdrop of integrated system theory, the purpose of this study was to determine the association between data privacy breaches, data storage locations, business associates, covered entities, and number of individuals affected. Study data consisted of secondary breach information retrieved from the Department of Health and Human Services Office of Civil Rights. Loglinear analytical procedures were used to examine U.S. healthcare breach incidents and …

Nigerian Cancer Survivors' Perceptions Of Care Received From Health Care Professionals, Olusegun Akinsuli

Walden Dissertations and Doctoral Studies

Cancer patients worldwide receive care from multidisciplinary teams, and patients

sometimes have little or no knowledge about the different treatment options available, making communication with their care providers an important influence in how they perceive their care. Patient satisfaction with care is an important factor in determining survivorship. The increasing prevalence of cancer worldwide has become a huge public health issue. The World Health Organization has warned that the potential gains from combatting infectious diseases in Nigeria might be lost because of the increasing prevalence of cancer. The purpose of this grounded theory study was to obtain the perceptions of …

Trigg's "Beyond Matter: Why Science Needs Metaphysics" (Book Review), John D. Laing

The Christian Librarian

No abstract provided.

Secondary General Education Teachers' Perceptions Of Challenges For Inclusion Students With Autism, Karen Clark Clark

Walden Dissertations and Doctoral Studies

Many secondary students with autism (SWA) included in the general education (GE) classroom demonstrate academic and behavioral challenges. Most GE teachers who have inclusive SWA in their classes receive little or no training on evidence-based practices to address these challenges. The purpose of this qualitative bounded case study was to explore secondary GE teachers' perceptions of and experiences with the academic and behavioral challenges of inclusive SWA. Theoretical frameworks of the weak central coherence theory for autism and executive dysfunction grounded the study. Data from 6 purposefully chosen secondary GE inclusion teachers, who educated SWA and students with autism spectrum …

Developing Sustainable Leadership Strategies To Increase Corporate Revenue, Linda Goulet Crosby

Walden Dissertations and Doctoral Studies

The business environment is in constant flux where stakeholders encourage organizational leaders to consider sustainable business tactics alongside corporate profits. While most business leaders recognize the importance of including sustainability into corporate goals, evidence suggested that only 10% have sustainable action plans in place. Using the honeybee leadership model as the conceptual framework, the purpose of this qualitative case study was to explore the sustainable leadership strategies that business leaders from small- and medium- sized companies integrated to increase corporate revenue. These companies were B Corp certified which ensures a third party endorsement of sustainable practices. The data were collected …

Perceptions On Interventions Impacting The Self- Efficacy Of At-Risk Students, Natalie Giddens Giddens

Walden Dissertations and Doctoral Studies

Teachers need interventions to improve at-risk students' self-efficacy, which may improve their academic performance in school. The purpose of this qualitative case study was to explore the perceptions of elementary school teachers at a Texas public middle school as to what research-based interventions they felt would improve the self-efficacy of these students. Bandura's social cognitive theory, which framed the study, indicates that self-efficacy beliefs affect the courses of action that people seek and the choices people make. Many at-risk students who experience a lack of academic success have low self-efficacy, which may affect their school performance. The research questions that …

Epistemic Skills Deficiency In The Project Management Body Of Knowledge, Alex Hosch

Walden Dissertations and Doctoral Studies

Information Technology (IT) projects continue to fail despite being managed by certified Project Management Professionals (PMP) and professionally trained non-certified Project Managers (PM). This study addressed PMPs and qualified PMs who continue to experience IT project failure at a high rate. The purpose of this qualitative multiple case study was to explore perspectives of PMs and their understanding of project management best practices in the Guide to the Project Management Body of Knowledge (PMBOK). There were 5 research questions focused on IT project failures, lessons learned, trends, deficiencies in project management framework, and adherence to standard PM practices. This study …

Kapic's "A Little Book For New Theologians: Why And How To Study Theology" (Book Review), Brad Doerksen

The Christian Librarian

No abstract provided.

Rosales' "Mathematizing: An Emergent Math Curriculum Approach For Young Children" (Book Review), Lori Thornton

The Christian Librarian

No abstract provided.

Cartledge's "The Mediation Of The Spirit: Interventions In Practical Theology" (Book Review), Linda Poston

The Christian Librarian

No abstract provided.

Effects Of An Integrated Electronic Health Record On An Academic Medical Center, Kenneth E. Koppenhaver Ii

Walden Dissertations and Doctoral Studies

The debate about healthcare reform revolves around a triple aim of improving the health of populations, improving the patient experience, and reducing the cost of care. A major tool discussed in this debate has been the adoption of electronic health record (EHR) systems to record and guide care delivery. Due to low adoption rates and limited examples of success, the problem was a lack of understanding by healthcare organizations of how the EHR fundamentally changes an organization through the interactions of people, processes, and technology over time. The purpose of this case study was to explore the people, processes, and …