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Secondary Teachers' Perceptions Of The Effectiveness Of A Professional Learning Community, Catina Shontelle Stewart
Secondary Teachers' Perceptions Of The Effectiveness Of A Professional Learning Community, Catina Shontelle Stewart
Walden Dissertations and Doctoral Studies
The implementation of professional learning communities (PLCs) in schools has been shown to serve as a catalyst in transforming school culture and increasing the academic performance of students. Our school district mandated that PLCs were established at the research site, an urban Louisiana school, for the primary purpose of closing the achievement gap. Yet, recent data from the local district indicate that these PLCs have not resulted in capacity building for sustainable improvement. Ineffective implementation of the current PLCs may have contributed to the poor outcomes. One purpose of this qualitative case study was to examine teachers' perceptions of the …
Effect Of Summer Bridge Programming On Students' Performance On The Texas Success Initiative Assessment, Consuela Michelle Cooper
Effect Of Summer Bridge Programming On Students' Performance On The Texas Success Initiative Assessment, Consuela Michelle Cooper
Walden Dissertations and Doctoral Studies
Summer bridge programs (SBPs) have been used as a means of increasing students' college readiness and academic skills. University Southeast implemented a SBP in 2013 for students placing into developmental courses on the Texas Success Initiative Assessment (TSIA). However, researchers have found mixed results when evaluating the effectiveness of SBPs, and at University Southeast, it has not been investigated. The purpose of this quantitative study was to examine the difference in TSIA score gains between first-time-in-college students with developmental-level test scores who attended a three-week SBP and those who did not. Tinto's longitudinal model of student departure guided the study …
Teachers' Theories Of Teaching And Learning And The Use Of Math Interventions, Nicole P. Jones
Teachers' Theories Of Teaching And Learning And The Use Of Math Interventions, Nicole P. Jones
Walden Dissertations and Doctoral Studies
Despite the academic gap between students with learning disabilities (LD) and their nondisabled peers, schools continue to educate students with LD in regular education classrooms. In secondary math classes, such as Algebra 1, students with LD have high percentages of failure. The purpose of this cross-sectional study was to examine the relationship between teachers' personal theories of teaching and learning and their use of math interventions. Fox's (1983) theoretical framework of teaching and learning was used as a conceptual lens. Surveys were administered to 20 high school math teachers in an urban Northeastern U.S. school district. An ordinal logistic regression …
The Effect Of Common Core Standards On Elementary Students' Learning, Christine Arner Macdougall
The Effect Of Common Core Standards On Elementary Students' Learning, Christine Arner Macdougall
Walden Dissertations and Doctoral Studies
After implementing the Common Core Standards in 2012, local school districts faced additional costs in their annual budgets to train staff how to teach using these standards. One of the problems that faced the school district under study was whether to retain the Common Core Standards and to continue to fund the expense of training teachers . The purpose of this study was to assess the influence of the Common Core Standards on student achievement in a local Pennsylvania school district using scores from the Pennsylvania System of School Assessments (PSSA) for Grades 3 through 8. The research question addressed …
Elementary Teachers' Perceptions Of Practices And Professional Development For Differentiating Mathematics Instruction, Sandra Mujagic Varajic
Elementary Teachers' Perceptions Of Practices And Professional Development For Differentiating Mathematics Instruction, Sandra Mujagic Varajic
Walden Dissertations and Doctoral Studies
Teachers and administrators in a Title I elementary school in a southeastern state are concerned that there has been a trend over the past 3 years of declining standardized assessment scores in mathematics for students in Grades 3, 4, and 5. The purpose of this qualitative case study was to explore teachers' perceptions of practices, and professional development (PD) for differentiating mathematics instruction. This study was grounded in the conceptual framework of Vygotsky's zone of proximal development and Tomlinson's differentiated instruction (DI). Purposeful sampling was used to select 8 teachers and 1 mathematics coach, who worked with students in Grades …
Understanding Of Phenolic Compound Retention Mechanisms On Pes-Uf Membrane, Amine Mnif, Meral Mouelhi, Bechir Hamrouni
Understanding Of Phenolic Compound Retention Mechanisms On Pes-Uf Membrane, Amine Mnif, Meral Mouelhi, Bechir Hamrouni
Turkish Journal of Chemistry
Ultrafiltration (UF) is investigated as a possible alternative to remove organic compounds from aqueous synthetic solution. This paper presents a comprehensive study towards a better understanding of phenolic compound retention mechanisms during UF processes. Thus, removal of phenol and resorcinol was studied using a polyethersulfone ultrafiltration (PES-UF) membrane. The influence of main operating conditions (feed concentration, transmembrane pressure, and pH) on the retention was evaluated. Membrane--solute interactions were found to play an important role during the process, suggesting the adsorption of the target compounds on the PES-UF membrane. The level of adsorption was consequently evaluated by measuring the quantity of …
Synthesis Of Pds/Zns--Cds-Type Photocatalysts Using Zns As Sulphide Source, Radu Banica, Petrica Linul, Cristina Mosoarca
Synthesis Of Pds/Zns--Cds-Type Photocatalysts Using Zns As Sulphide Source, Radu Banica, Petrica Linul, Cristina Mosoarca
Turkish Journal of Chemistry
In this work, a new method for the growth of large CdS crystals into PdS/ZnS--CdS-type photocatalysts is presented. In order to accomplish this, in the first stage zinc sulphide was synthesised and hydrothermally crystallised. In the second stage, after PdS decoration, the recrystallised zinc sulphide was utilised as sulphur source for the synthesis of PdS/ZnS--CdS-type photocatalysts. The photocatalysts were characterised by X-ray diffraction, transmission electron microscopy, energy dispersive X-ray spectroscopy, and diffuse reflectance spectroscopy. In the third stage magnetic polymer supports were manufactured and loaded with photocatalyst. Finally photocatalysis experiments under blue light illumination were conducted for the hydrogen evolution …
Ultrasound-Assisted Surfactant/Ionic Liquid Aqueous Two-Phase System Extraction Prior To High Performance Liquid Chromatography For The Determination Of Tetracyclines In Milk And Honey Samples, Hayri̇ye Mi̇ne Antep, Taşkin Mumcu, Kami̇l Bostanci, Serap Seyhan Bozkurt, Melek Merdi̇van
Ultrasound-Assisted Surfactant/Ionic Liquid Aqueous Two-Phase System Extraction Prior To High Performance Liquid Chromatography For The Determination Of Tetracyclines In Milk And Honey Samples, Hayri̇ye Mi̇ne Antep, Taşkin Mumcu, Kami̇l Bostanci, Serap Seyhan Bozkurt, Melek Merdi̇van
Turkish Journal of Chemistry
In this work, an ultrasonic-assisted surfactant/ionic liquid aqueous two-phase system (ATPS) extraction method was developed to extract six tetracycline antibiotics from food samples before their chromatographic determination using high performance liquid chromatography. The ATPS was formed with 1-allyl-3-methyl-imidazolium bromide, Triton X-100, and dipotassium hydrogen phosphate. The parameters including type and amount of surfactant, ionic liquid and salt, pH of sample solution, and sonication time were optimized. Under the optimized conditions, linear calibration curves of the six tetracyclines were obtained in the range of 10--500 $\mu $g L$^{-1}$ with $>$ r$^{2} =$ 0.990 (n $=$ 9). The proposed green analytical …
Spectrophotometric Detection Of Rhodamine B In Tap Water, Lipstick, Rouge, And Nail Polish Samples After Supramolecular Solvent Microextraction, Nebi̇ye Özkantar, Mustafa Soylak, Mustafa Tüzen
Spectrophotometric Detection Of Rhodamine B In Tap Water, Lipstick, Rouge, And Nail Polish Samples After Supramolecular Solvent Microextraction, Nebi̇ye Özkantar, Mustafa Soylak, Mustafa Tüzen
Turkish Journal of Chemistry
A simple and sensitive supramolecular solvent-based dispersive liquid--liquid microextraction method was described for the separation/preconcentration and spectrophotometric detection of rhodamine B. The microextraction method, which was realized at ambient temperature for the detection of rhodamine B, was carried out by using supramolecular solvents such as tetrahydrofuran and decanoic acid. The method was based on analyses of rhodamine B by using UV-Vis spectrophotometry at 558 nm. The influences of some parameters such as pH, sample volume, eluent solutions, centrifugation time, and ultrasonic bath time were optimized. The effects of various matrix ions were also investigated. Moreover, the limit of detection and …
A Promising Materials Approach To Combatting Renal Hyperphosphatemia: Fe(Ii)-Montmorillonites, Xiaotong Yuan, Dawei Qin, Min Qiao, Gang Liu, Hongxin Li, Xia Niu
A Promising Materials Approach To Combatting Renal Hyperphosphatemia: Fe(Ii)-Montmorillonites, Xiaotong Yuan, Dawei Qin, Min Qiao, Gang Liu, Hongxin Li, Xia Niu
Turkish Journal of Chemistry
The objective of the current effort was to determine the efficacy of Fe(II)-montmorillonite (Fe(II)-MMT) as an adjuvant for specific targeted adsorption of phosphate. Specifically, Fe(II)-MMT was studied to combat hyperphosphatemia and anemia arising from chronic renal failure. The adsorption of phosphate over time, pH, and initial concentration was studied. The systems were characterized by X-ray diffraction (XRD), Raman, and zeta potential. The experimental results demonstrated the adsorption time was set to 140 min to achieve maximum adsorption efficiency. It was thus found that the maximum adsorption was at pH 3.0. In addition, it reached equilibrium when the initial phosphate concentration …
Recent Advances In Thymidine Phosphorylase Inhibitors: Syntheses And Prospective Medicinal Applications, Muhammad Aamir Sajid, Zulfiqar Ali Khan, Sohail Anjum Shahzad, Syed Ali̇ Raza Naqvi, Muhammad Usman, Ahsan Iqbal
Recent Advances In Thymidine Phosphorylase Inhibitors: Syntheses And Prospective Medicinal Applications, Muhammad Aamir Sajid, Zulfiqar Ali Khan, Sohail Anjum Shahzad, Syed Ali̇ Raza Naqvi, Muhammad Usman, Ahsan Iqbal
Turkish Journal of Chemistry
This review paper covers recent advances in the synthetic strategies for novel TPase inhibitors and their potential medicinal applications over the last few decades. A brief introduction covering the structural aspects of TPase inhibitors is also included to facilitate understanding of diverse approaches to monitor the design of new inhibitors. TPase is an essential enzyme and its inhibition is a potential target in the development of anticancer drugs.
Supramolecular Solvent Microextraction Of Uranium At Trace Levels From Water And Soil Samples, Mansoor Khan, Erkan Yilmaz, Mustafa Soylak
Supramolecular Solvent Microextraction Of Uranium At Trace Levels From Water And Soil Samples, Mansoor Khan, Erkan Yilmaz, Mustafa Soylak
Turkish Journal of Chemistry
A supramolecular solvent microextraction procedure was established for the separation/preconcentration of uranium(VI) (U(VI)) prior to its determination by UV-Vis spectrophotometry. 1-(2-Pyridylazo)-2-naphthol (PAN) was used to form a red chelate (U-PAN) with U(VI) at pH 10. U-PAN was extracted by undecanol in tetrahydrofuran. All the parameters that affect extraction efficiency like solution pH, amount of ligand, type and volume of supramolecular solvent, sample volume, and diverse ion effect were optimized. The preconcentration factor was 17. The detection limit was 0.31 $\mu $g L$^{-1}$. The method was validated using GBW07424 (GSS-10 certified reference material). Microextraction was also applied to water and soil …
Graphite Oxide Catalyzed Synthesis Of $\Beta $-Amino Alcohols By Ring-Opening Of Epoxides, Maryam Mirza-Aghayan, Farzaneh Alvandi, Mahdieh Molaee Tavana, Rabah Boukherroub
Graphite Oxide Catalyzed Synthesis Of $\Beta $-Amino Alcohols By Ring-Opening Of Epoxides, Maryam Mirza-Aghayan, Farzaneh Alvandi, Mahdieh Molaee Tavana, Rabah Boukherroub
Turkish Journal of Chemistry
Graphite oxide as a heterogeneous and recyclable solid acid catalyzed a simple and efficient method for the synthesis of $\beta $-amino alcohols by ring opening of epoxides with amines. This method is effective with various aromatic and aliphatic amines under solvent-free conditions. The corresponding $\beta $-amino alcohols are obtained in high yields (56%-95%) and short reaction times (15-30 min) with high regio- and chemoselectivity under metal-free conditions.
Synthesis And Antifungal Activity Of New Dihydrofurocoumarins And Dihydrofuroquinolines, Asli Ustalar, Mehmet Yilmaz, Agi̇m Osmani̇, Sema Aşkin Keçeli̇
Synthesis And Antifungal Activity Of New Dihydrofurocoumarins And Dihydrofuroquinolines, Asli Ustalar, Mehmet Yilmaz, Agi̇m Osmani̇, Sema Aşkin Keçeli̇
Turkish Journal of Chemistry
We investigated the radical addition of 4-hydroxycoumarin (1a) and 4-hydroxyquinoline (1b) with conjugated dienes ({2a-f) mediated by cerium(IV) ammonium nitrate (CAN) resulting in ethenyl substituted 2,3-dihydrofurocoumarin (3a-f) and 3,5-dihydrofuroquinoline (3g, 3h) compounds in moderate to good yields. All compounds were characterized by spectroscopic methods (IR, MS, and $^{1}$H and $^{13}$C NMR) and microanalysis. Antifungal activities of these compounds were investigated against the fungi Candida albicans, C. parapsilosis, C. krusei, C. glabrata, C. tropicalis, and Aspergillus fumigatus.
Synthesis And Cytotoxicity Of Novel Thioxo-Quinazolino[3,4-$A$]Quinazolinones, Negar Mohammadhosseini, Mina Saeedi, Shahram Moradi, Mohammad Mahdavi, Omidreza Firuzi, Alireza Foroumadi, Abbas Shafiee
Synthesis And Cytotoxicity Of Novel Thioxo-Quinazolino[3,4-$A$]Quinazolinones, Negar Mohammadhosseini, Mina Saeedi, Shahram Moradi, Mohammad Mahdavi, Omidreza Firuzi, Alireza Foroumadi, Abbas Shafiee
Turkish Journal of Chemistry
Various thioxo-quinazolino[3,4-$a$]quinazolinones were prepared and evaluated for their cytotoxicity in MOLT-4 (lymphoblastic leukemia) and MCF-7 (breast adenocarcinoma) cell lines. Synthesis of the target compounds was started from isatoic anhydride. Successive reaction of isatoic anhydride with benzylamine and 2-nitrobenzaldehyde, reduction of the nitro group, and reaction with CS$_{2}$ gave 12-benzyl-6-thioxo-6,7,11b,12-tetrahydro-13$H$-quinazolino[3,4-$a$]quinazolin-13-one. The latter compound reacted with various 2-chloro-$N$-substituted acetamides to afford the corresponding fused quinazolinone derivatives.
Investigation Of The Effects Of Purification And Characterization Of Turkey (Meleagris Gallopavo) Liver Mitochondrial Thioredoxin Reductase Enzyme And Some Metal Ions On Enzyme Activity, Yusuf Temel, Ö. İrfan Küfrevi̇oğlu, Mehmet Çi̇ftci̇
Investigation Of The Effects Of Purification And Characterization Of Turkey (Meleagris Gallopavo) Liver Mitochondrial Thioredoxin Reductase Enzyme And Some Metal Ions On Enzyme Activity, Yusuf Temel, Ö. İrfan Küfrevi̇oğlu, Mehmet Çi̇ftci̇
Turkish Journal of Chemistry
The thioredoxin system, found in all living creatures, consists of thioredoxin protein (Trx), thioredoxin reductase enzyme (TrxR), and NADPH. In this study, turkey liver mitochondrial TrxR enzyme with 3.07 EU $\times $ mg$^{-1}$ specific activity was purified 990-fold in a yield of 2.05{\%} using 2',5'-ADP Sepharose 4B affinity chromatography. The purity of the enzyme was measured and the molecular weight of its subunits was determined to be 45.5 kDa by SDS-PAGE. The molecular mass of the enzyme's natural state was found to be 88 kDa using Sephadex-G 150 gel filtration chromatography. In addition, characteristic and kinetic properties of the enzyme …
Electrochemical Detection Of Dna Interaction With Mannich Base Derivatives By Disposable Graphite Electrodes, Hüseyi̇n İstanbullu, Hakan Karadeni̇z, Erçi̇n Erci̇yas, Kadri̇ye Arzum Erdem Gürsan
Electrochemical Detection Of Dna Interaction With Mannich Base Derivatives By Disposable Graphite Electrodes, Hüseyi̇n İstanbullu, Hakan Karadeni̇z, Erçi̇n Erci̇yas, Kadri̇ye Arzum Erdem Gürsan
Turkish Journal of Chemistry
Four different Mannich base derivatives containing an aromatic/heteroaromatic propanone structure (C1 (3-(dimethylamino)-1-(thiophen-2-yl)propan-1-one hydrochloride); C2 (3-morpholino-1-(pyridin-3-yl)propan-1-one hydrochloride); C3 (3-(dimethylamino)-1-(1H-indol-3-yl)propan-1-one hydrochloride), C4 (3-(piperidin-1-yl)-1-(pyren-1-yl)propan-1-one hydrochloride)) were earlier synthesized and characterized with $^{1}$H NMR, $^{13}$C NMR, MS, and elemental analysis. The interaction of these compounds with fish sperm double stranded DNA (fs-dsDNA) was investigated by using differential pulse voltammetry (DPV) in connection with a disposable pencil graphite electrode (PGE). After the interaction procedure, there was a meaningful decrease in the oxidation signal of the electroactive DNA base guanine due to possible intercalation and/or alkylation mechanism between these Mannich base derivatives and DNA. The features …
Highly Selective Schiff Base Derivatives For Colorimetric Detection Of Al$^{3+}$, Zi̇ya Aydin, Mustafa Keleş
Highly Selective Schiff Base Derivatives For Colorimetric Detection Of Al$^{3+}$, Zi̇ya Aydin, Mustafa Keleş
Turkish Journal of Chemistry
Schiff base derivatives NBAR and NSAR were developed for selective detection of Al$^{3+}$ in aqueous solution. UV-vis spectroscopic studies revealed that NBAR and NSAR showed marked sensitivity and selectivity to Al$^{3+}$ in acetonitrile (ACN)/water (v/v, 1:1, pH 6.80). The NBAR and NSAR receptors bound Al$^{3+}$ in a 2:1 stoichiometry with apparent binding constants 4.09 $\times $ 10$^{11}$ M$^{-2}$ and 1.65 $\times $ 10$^{12}$ M$^{-2}$, respectively. They also displayed distinct changes in color upon the alteration of free Al$^{3+}$ levels in solution with reversible responses and showed little interference with other metal ions.
Sonochemical Degradation Of Basic Red 29 In Aqueous Media, Zineb Boutamine, Slimane Merouani, Oualid Hamdaoui
Sonochemical Degradation Of Basic Red 29 In Aqueous Media, Zineb Boutamine, Slimane Merouani, Oualid Hamdaoui
Turkish Journal of Chemistry
In this work, the degradation of Basic Red 29 (BR29), an azo dye, was investigated using a high-frequency ultrasonic reactor (300 kHz). The influence of several parameters such as initial substrate concentration (5--200 mg L$^{-1})$, pH (3-10.1), ultrasonic power (20-80 W), and nature of the dissolved gas (Ar, air, and N$_{2})$ on the degradation of BR29 was assessed. Additionally, the impact of natural matrices (seawater and natural and river waters) on the degradation rate of BR29 was clarified. Degradation experiments with radical scavengers, tert-butyl alcohol and glucose, showed that BR29 degraded mainly through HO$^{\bullet }$ radical attack at the gas/liquid …
Isocoumarins And 3,4-Dihydroisocoumarins, Amazing Natural Products: A Review, Aisha Saddiqa, Osman Çakmak, Muhammad Usman
Isocoumarins And 3,4-Dihydroisocoumarins, Amazing Natural Products: A Review, Aisha Saddiqa, Osman Çakmak, Muhammad Usman
Turkish Journal of Chemistry
The isocoumarins are naturally occurring lactones that constitute an important class of natural products exhibiting an array of biological activities. A wide variety of these lactones have been isolated from natural sources and, due to their remarkable bioactivities and structural diversity, great attention has been focused on their synthesis. This review article focuses on their structural diversity, biological applications, and commonly used synthetic modes.
Spectrophotometric Determination Of Carmoisine After Cloud Point Extraction Using Triton X-114, Aslihan Karatepe, Çağri Akalin, Mustafa Soylak
Spectrophotometric Determination Of Carmoisine After Cloud Point Extraction Using Triton X-114, Aslihan Karatepe, Çağri Akalin, Mustafa Soylak
Turkish Journal of Chemistry
Carmoisine (E122) is a synthetic azo dye that is generally used to give a red color to food products. In this work, a sensitive and simple method was developed for the determination of carmoisine based on cloud point extraction. To obtain the optimum conditions for the extraction efficiency of carmoisine, the effects of different analytical parameters such as H$_{2}$SO$_{4}$ concentration, concentration of Triton X-114, and equilibrium temperature were studied. The calibration graph was linear between 0.05 and 5.0 $\mu $g/mL and the detection limit based on three times the standard deviation of the blank was 7.2 $\mu $g/L. The method …
Syntheses And Photoluminescence Properties Of New Zn(Ii) And Cd(Ii) Coordination Polymers Prepared From 5-Sulfoisophthalate Ligand, Fati̇h Semerci̇
Syntheses And Photoluminescence Properties Of New Zn(Ii) And Cd(Ii) Coordination Polymers Prepared From 5-Sulfoisophthalate Ligand, Fati̇h Semerci̇
Turkish Journal of Chemistry
New coordination polymers, formulated as {[Zn($\mu $-sipH)($\mu $-apim)]$\cdot $3H$_{2}$O} $_{n}$ (1) and {[Cd($\mu $-sip)(H$_{2}$O)$_{2}$ (apimH)]$\cdot $3H$_{2}$O}$_{n}$ (2) were synthesized based on the 1-(3-aminopropyl)imidazole (apim) along with 5-sulfoisophthalate (sip) ligands. The complexes were synthesized under mild hydrothermal conditions. All the complexes were characterized by elemental analysis, FT-IR spectroscopy, and single-crystal X-ray diffraction studies. The X-ray crystallographic studies of 1 and 2 reveal Zn(II) and Cd(II) ions are $\mu $-bridged by dianionic sipH and trianionic sip ligands in bis(monodentate) and bis(bidentate) coordination mode, respectively, to generate 1D polymer chains. In complex 1, the adjacent chains are linked by two apim ligands to …
Impact Of Surface Modification Of Green Algal Biomass By Phosphorylation On The Removal Of Copper(Ii) Ions From Water, Zakaria Al-Qodah, Mohammad Al-Shannag, Abdulaziz Amro, Eman Assirey, Mustafa Bob, Khalid Bani-Melhem, Malek Alkasrawi
Impact Of Surface Modification Of Green Algal Biomass By Phosphorylation On The Removal Of Copper(Ii) Ions From Water, Zakaria Al-Qodah, Mohammad Al-Shannag, Abdulaziz Amro, Eman Assirey, Mustafa Bob, Khalid Bani-Melhem, Malek Alkasrawi
Turkish Journal of Chemistry
A series of batch lab-scale experiments were performed to investigate the performance of dead phosphorylated algal biomass of Spirogyra species for the bioadsorption of Cu$^{+2}$ ions from aqueous solutions. FT-IR and SEM analyses were performed to characterize the phosphorylated and raw algae. The SEM analysis indicated that the phosphorus content increases by about 5 times. The isotherm equilibrium data indicated that phosphorylation enhances the removal of Cu$^{+2}$ from water by about 20%. The experimental isotherms fit well to Langmuir models with $R^{2}$ values close to 0.99. Adsorption kinetic study was conducted to investigate the effect of initial Cu$^{+2}$ concentrations, pH, …
Synthesis And Anticancer And Cytotoxic Effects Of Novel 1,4-Phenylene-Bis-N-Thiocarbamoylpyrazole And 1,4-Phenylene-Bis-Pyrazolylthiazole Derivatives, Meli̇ha Burcu Gürdere, Erdoğan Kamo, Yakup Budak, Ayşe Şahi̇n Yağlioğlu, Mustafa Ceylan
Synthesis And Anticancer And Cytotoxic Effects Of Novel 1,4-Phenylene-Bis-N-Thiocarbamoylpyrazole And 1,4-Phenylene-Bis-Pyrazolylthiazole Derivatives, Meli̇ha Burcu Gürdere, Erdoğan Kamo, Yakup Budak, Ayşe Şahi̇n Yağlioğlu, Mustafa Ceylan
Turkish Journal of Chemistry
Thiazolylpyrazoline derivatives were recently reported as potent anticancer agents. In this study, novel 1,4-phenylene-bis-N-thiocarbamoylpyrazoles (3a-h and 1,4-phenylene-bis-pyrazolylthiazoles (5a-h were prepared and screened for their anticancer activities against C6 (rat brain tumor cells) and HeLa (human uterus carcinoma). Anticancer activity studies were performed as a dose-dependent assay starting with eight concentrations. 5-Fluorouracil (5-FU) was used as a positive control. Compounds 3c, 3d, and 3h were examined and they revealed almost the same activities compared with 5-FU in terms of cell selectivity against C6 cells. Moreover, compounds 3a-h had lower cytotoxicity than 5-FU. The low cytotoxicity values of 3a-h as well as …
Hydrolysis Of Ammonia Borane And Hydrazine Borane By Poly($N$-Vinyl-2-Pyrrolidone)-Stabilized Copd Nanoparticles For Chemical Hydrogen Storage, Murat Rakap, Bayram Abay, Ni̇hat Tunç
Hydrolysis Of Ammonia Borane And Hydrazine Borane By Poly($N$-Vinyl-2-Pyrrolidone)-Stabilized Copd Nanoparticles For Chemical Hydrogen Storage, Murat Rakap, Bayram Abay, Ni̇hat Tunç
Turkish Journal of Chemistry
For the first time the synthesis of poly($N$-vinyl-2-pyrrolidone)-stabilized cobalt-palladium nanoparticles by an easy method, their characterization, and their use as active catalysts for hydrogen release from hydrolysis of ammonia borane and hydrazine borane is reported here. The catalyst is prepared by simultaneous reduction of suitable cobalt and palladium ions by sodium borohydride in the presence of poly($N$-vinyl-2-pyrrolidone) as a stabilizer. They are characterized by UV-Vis spectroscopy, TEM analysis, X-ray diffraction, and X-ray photoelectron spectroscopy. They provide average turnover frequencies of 30 min$^{-1}$ and 45 min$^{-1}$ in the hydrolysis of ammonia borane and hydrazine borane. They also provide activation energies of …
Synthesis And In Vitro Anticancer Evaluation Of 1,4-Phenylene-Bis-Pyrimidine-2-Amine Derivatives, Meli̇ha Burcu Gürdere, Erdoğan Kamo, Ayşe Şahi̇n Yağlioğlu, Yakup Budak, Mustafa Ceylan
Synthesis And In Vitro Anticancer Evaluation Of 1,4-Phenylene-Bis-Pyrimidine-2-Amine Derivatives, Meli̇ha Burcu Gürdere, Erdoğan Kamo, Ayşe Şahi̇n Yağlioğlu, Yakup Budak, Mustafa Ceylan
Turkish Journal of Chemistry
A series of 1,4-phenylene-bis-chalcones 3a-3h were synthesized by the reaction of terephthalaldehyde with substituted arylketones in this study. The novel 1,4-phenylene-bis-pyrimidine-2-amine derivatives 5a-5h were obtained by the addition of guanidine hydrochloride to 1,4-phenylene-bis-chalcone 3a-3h in ethanolic KOH under reflux conditions. The structure of the compounds was explained by means of IR, $^{1}$H NMR, $^{13}$C NMR, and elemental analyses. The anticancer activities of 3a-3h and 5a-5h were investigated against rat brain tumor cells and human uterus carcinoma in vitro$.$ Activity tests were performed as dose-dependent assays at eight concentrations. The positive control was 5-fluorouracil (5-FU). Compounds 3c and 3d were examined …
Investigation Of Solvent Effect On Photophysical Properties Of Some Sulfonamides Derivatives, Ebru Bozkurt, Hali̇se İnci̇ Gül, Mehtap Tuğrak
Investigation Of Solvent Effect On Photophysical Properties Of Some Sulfonamides Derivatives, Ebru Bozkurt, Hali̇se İnci̇ Gül, Mehtap Tuğrak
Turkish Journal of Chemistry
The photophysical properties of new sulfonamides synthesized recently were investigated in different solvents. Shifts in the absorption and fluorescence spectra of both compounds (S10 and S11) occurred depending on the solvents used. Ground and excited state dipole moments of the molecules were calculated using the spectral shifts of the compounds in different solvents and polarity function of solvents, respectively. They were 1.32 and 1.46 D for S10 and 1.71 and 4.89 D for S11. These results suggested that the excited state dipole moments are greater than those in ground state for both molecules. This means that the dyes were more …
Efficient Multicomponent Synthesis Of 1,2,3-Triazoles Catalyzed By Cu(Ii) Supported On Pei@Fe$_{3}$O$_{4}$ Mnps In A Water/Peg$_{300}$ System, Zeinab Hassanpour, Aziz Maleki, Morteza Hosseini, Lena Gorgannezhad, Vajihe Nejadshafiee, Ali Ramazani, Ismaeil Haririan, Abbas Shafiee, Mehdi Khoobi
Efficient Multicomponent Synthesis Of 1,2,3-Triazoles Catalyzed By Cu(Ii) Supported On Pei@Fe$_{3}$O$_{4}$ Mnps In A Water/Peg$_{300}$ System, Zeinab Hassanpour, Aziz Maleki, Morteza Hosseini, Lena Gorgannezhad, Vajihe Nejadshafiee, Ali Ramazani, Ismaeil Haririan, Abbas Shafiee, Mehdi Khoobi
Turkish Journal of Chemistry
A highly dispersible and magnetically recoverable Cu-PEI@Fe$_{3}$O$_{4}$ MNPs catalyst was prepared and successfully applied in one-pot three-component coupling of terminal alkynes, sodium azide, and alkyl bromides/chlorides in water to give 1,4-disubstituted 1,2,3-triazoles with good to excellent yields. The catalyst was fully characterized with FT-IR, TGA, TEM, SEM, VSM, EDX, cyclic voltammetry, and ICP-AES spectroscopic techniques. Furthermore, the catalyst was easily recycled by an external magnet and successfully reused six times in the reaction without significant loss of its catalytic activity and copper leaching. The large-scale reaction was also carried out in the absence of any base and reducing agent even …
Synthesis And Photovoltaic Characterization Of Triarylamine-Substituted Quinoxaline Push-Pull Dyes To Improve The Performance Of Dye-Sensitized Solar Cells, Kadi̇r Demi̇rak, Mustafa Can, Ci̇han Özsoy, Mesude Zeli̇ha Yi̇ği̇t, Burak Gülteki̇n, Şerafetti̇n Demi̇ç, Ceylan Zafer
Synthesis And Photovoltaic Characterization Of Triarylamine-Substituted Quinoxaline Push-Pull Dyes To Improve The Performance Of Dye-Sensitized Solar Cells, Kadi̇r Demi̇rak, Mustafa Can, Ci̇han Özsoy, Mesude Zeli̇ha Yi̇ği̇t, Burak Gülteki̇n, Şerafetti̇n Demi̇ç, Ceylan Zafer
Turkish Journal of Chemistry
Novel unsymmetrical organic sensitizers having donor, $\pi $-spacer, and anchoring groups were designed and synthesized for dye-sensitized solar cell (DSSC) application. The dyes 3-{4-[7-(4-{bis[4-(hexyl)phenyl]amino} phenyl)-11,12-dibutoxy-1,4,5,8-tetrahydrodibenzo [a, c] phenazine-2-yl]phenyl} -2-cyano acrylic acid (KD-148) and 3-{5-[7-(4-{bis[4-(hexyloxy)phenyl]amino} phenyl)-11,12-dibutoxy-1,4,5,8-tetrahydrodibenzo [a, c] phenazine-2-yl]-2-thienyl} -2-cyano acrylic acid (KD-150) were anchored onto TiO$_{2}$ and tested with ionic liquid electrolyte. The monochromatic incident photon-to-current conversion efficiencies (IPCE) of the dyes were 50% and 60% at 420 nm, respectively. The KD-150-sensitized solar cell gave a short-circuit current (I$_{SC})$ of 7.37 mA/cm$^{2}$, an open-circuit voltage (V$_{oc})$ of 560 mV, a fill factor (FF) of 0.56, and overall conversion efficiency ($\eta …
Synthesis, Characterization, And Antimicrobial Activities Of Novel Monosaccharide-Containing Schiff Base Ligands, Fatma Telli̇, Stephen Thomas Astley, Azi̇ze Yeşi̇m Salman
Synthesis, Characterization, And Antimicrobial Activities Of Novel Monosaccharide-Containing Schiff Base Ligands, Fatma Telli̇, Stephen Thomas Astley, Azi̇ze Yeşi̇m Salman
Turkish Journal of Chemistry
Four new chiral Schiff base ligands (3a-4a, 3b-4b) have been prepared using aminoisopropylidene derivatives of glucose and aminochloralose derivatives of mannose. The synthesized compounds 1 and 2 were characterized by nuclear magnetic resonance ($^{1}$H and $^{13}$C NMR), Fourier transform infrared spectroscopy (FTIR), UV/visible spectroscopy, and elemental analysis. A total of eight Schiff base compounds (3a-6a, 3b-6b) were tested for antimicrobial activity against Escherichia coli ATCC 12228, Staphylococcus aureus ATCC 6538, Klebsiella pneumoniae CCM 2318, Pseudomonas aeruginosa ATCC 27853, Salmonella typhimurium CCM 5445, Enterococcus faecalis ATCC 29212, Bacillus subtilis ATCC 6633, and Candida albicans ATCC 10239 and exhibited a range of …