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2019

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Imsa 2019 Profile, Office Of College And Academic Counseling Jan 2019

Imsa 2019 Profile, Office Of College And Academic Counseling

IMSA Profile

The Illinois Mathematics and Science Academy (IMSA) fosters the discoverers. The thinkers. The innovators and experimenters. The problem-solvers of the future who can change the world through their life’s work. IMSA innovates the future of science, technology, engineering and math (STEM) education. It creates a strong and diverse pipeline of talented students at its tuition-free residential academy in Aurora, IL for 10th through 12th grade students. IMSA’s mission is to ignite and nurture creative, scientific, ethical minds that advance the human condition.

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Catalytic Hydrogenation Of Furfural And Furfuryl Alcohol To Fuel Additives And Value-Added Chemicals, Obaid Aldosari, Hamed Alshammari, Mosaed Alhumaimess, Ibrahim Wawata Jan 2019

Catalytic Hydrogenation Of Furfural And Furfuryl Alcohol To Fuel Additives And Value-Added Chemicals, Obaid Aldosari, Hamed Alshammari, Mosaed Alhumaimess, Ibrahim Wawata

Turkish Journal of Chemistry

The selective hydrogenation of furfural and furfuryl alcohol at different temperatures has been studied using several catalysts. The effect of various reaction conditions (pressure, catalyst amount, and solvent) was studied. We have shown that Pd/TiO$_{2}$ catalysts can be very effective for the synthesis of 2-methylfuran at room temperature. Using octane as a solvent, the solvent effectiveness was investigated and showed actively high selectivity towards 2-methylfuran and furfuryl alcohol, but there were many byproducts that were still noticed. Although adding Ru to the Pd/TiO$_{2}$ catalyst contributed to reducing the catalytic activity, this addition improved the selectivity to 2-methylfuran and furfuryl alcohol …

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Preparation And Physicochemical Characterization Of Zinc Oxide/Sodium Cellulose Composite For Food Packaging, Sherif Mohamed Abdel Salam Keshk, Mohamed Saad Hamdy Jan 2019

Preparation And Physicochemical Characterization Of Zinc Oxide/Sodium Cellulose Composite For Food Packaging, Sherif Mohamed Abdel Salam Keshk, Mohamed Saad Hamdy

Turkish Journal of Chemistry

Zinc oxide/sodium cellulose composite with different ZnO loadings was prepared for the first time. The crystal structures of cellulose, sodium cellulose, and ZnO/sodium cellulose composite were characterized by FT-IR, XRD, XPS, SEM, and EDX. ZnO/sodium cellulose showed a similar XRD pattern to that of cellulose II. The XPS spectrum emphasized the presence of Zn$^{2+}$ and Na$^{+\, }$ ions in the prepared composite. Additionally, the SEM analysis showed the growth of ZnO crystals on the sodium cellulose surface. UV-Vis spectrometry of the ZnO/sodium cellulose spectrum showed a distinguished absorption band at 360 nm that was attributed to the presence of ZnO …

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An Insight Into The Therapeutic Potential Of Piperazine-Based Anticancer Agents, Kamran Walayat, Noor Ul Amin Mohsin, Sana Aslam, Matloob Ahmad Jan 2019

An Insight Into The Therapeutic Potential Of Piperazine-Based Anticancer Agents, Kamran Walayat, Noor Ul Amin Mohsin, Sana Aslam, Matloob Ahmad

Turkish Journal of Chemistry

The piperazine ring system is among the medicinally important nitrogen-containing heterocyclic ring systems and is exploited for the synthesis of various drug molecules. A number of FDA-approved anticancer drugs contain piperazine rings and thus it is considered as an attractive scaffold having extraordinary potential for the development of new anticancer agents. In recent decades there has been an alarming increase in the number of people suffering from cancerous diseases all over the world, which resulted in an extraordinary increase in research reports on new anticancer drug candidates. The aim of this article is to highlight the structural parameters imparting anticancer …

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Efficient Synthesis And Antifungal Investigation Of Nucleosides' Quaternary Ammonium Salt Derivatives, Barbara Dmochowska, Lucyna Pellowska-Januszek, Justyna Samaszko-Fiertek, Rafal Slusarz, Roland Wakiec, Janusz Madaj Jan 2019

Efficient Synthesis And Antifungal Investigation Of Nucleosides' Quaternary Ammonium Salt Derivatives, Barbara Dmochowska, Lucyna Pellowska-Januszek, Justyna Samaszko-Fiertek, Rafal Slusarz, Roland Wakiec, Janusz Madaj

Turkish Journal of Chemistry

Quaternary ammonium salts are a group of compounds with diverse biological properties, the most important of which are their antiviral, antibacterial, and antifungal activities. The quaternization reactions of 5'-$O$-tosyl derivatives of uridine and thymidine with triethylamine, trimethylamine, 4-($N$,$N$-dimethylamino)pyridine, 2-methylpyridine, and pyridine are described in this article. Two of the synthesized compounds are exceptional because they are first of this type that demonstrate concentration-dependent antifungal in vitro activity against two species of the genus Candida in minimal YNB-SG medium. The experimental results have been extended by adding full atom molecular dynamics simulations and substrates and products energies evaluation.

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Plasma O$_{2}$ Modifies The Structure Of Synthetic Zeolite-A To Improve The Removal Of Cadmium Ions From Aqueous Solutions, Alaa Fahmy, Ahmed Elzaref, Hanan Youssef, Hassan Shehata, Magdy Wassel, Jörg Friedrich, Fabienne Poncin-Epaillard, Dominique Debarnot Jan 2019

Plasma O$_{2}$ Modifies The Structure Of Synthetic Zeolite-A To Improve The Removal Of Cadmium Ions From Aqueous Solutions, Alaa Fahmy, Ahmed Elzaref, Hanan Youssef, Hassan Shehata, Magdy Wassel, Jörg Friedrich, Fabienne Poncin-Epaillard, Dominique Debarnot

Turkish Journal of Chemistry

The present study addresses the removal of cadmium ions (Cd(II)) from aqueous solutions at a pH of 7.5 using zeolite-A activated by exposure to oxygen plasma. The activation process was performed over a wide range of plasma powers (10, 20, 30, and 40 W) and exposure times (30 to 360 s). Oxygen plasma cannot chemically modify zeolite to a considerable extent, but it can clean the surface, open blocked pores, and induce the formation of additional OH groups via exposure to humidity in ambient air. Therefore, Cd$^{+2}$ ion removal is increased by approximately 10% with the plasma treatments. Infrared-attenuated total …

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Effect Of Polyvinyl Alcohol/Chitosan Blend Ratios On Morphological, Optical, And Thermal Properties Of Electrospun Nanofibers, Gökhan Açik, Musa Kamaci, Burak Özata, Cahi̇de Eli̇f Özen Cansoy Jan 2019

Effect Of Polyvinyl Alcohol/Chitosan Blend Ratios On Morphological, Optical, And Thermal Properties Of Electrospun Nanofibers, Gökhan Açik, Musa Kamaci, Burak Özata, Cahi̇de Eli̇f Özen Cansoy

Turkish Journal of Chemistry

In this study, the electrospinning method was used to prepare polyvinyl alcohol (PVA)/chitosan (CS) blend nanofibers from their solutions. The effect of blend ratios (PVA/CS: 1%, 3%, 5%, and 7% (w/w)), applied voltage, and flow rate on the morphological, optical, and thermal properties of electrospun nanofibers were investigated by scanning electron microscopy (SEM), fluorescence and UV-Vis spectroscopies, and thermogravimetric analysis (TGA), respectively. Fourier transform infrared spectroscopy analysis indicated the existence of related functional groups of both PVA and CS in the electrospun fibers. During the electrospinning process, the maximum possible ratio of CS was 7% (w/w). SEM images indicated that …

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An Evaluation Of The Adsorption Dynamics Of Phosphate Ions Onto Fe(Ii)-Montmorillonites, Dawei Qin, Shuhua Chang, Min Qiao, Xiaotong Yuan, Wei Liu, Gang Liu Jan 2019

An Evaluation Of The Adsorption Dynamics Of Phosphate Ions Onto Fe(Ii)-Montmorillonites, Dawei Qin, Shuhua Chang, Min Qiao, Xiaotong Yuan, Wei Liu, Gang Liu

Turkish Journal of Chemistry

Fe(II)-montmorillonites (Fe(II)-MMTs) were prepared by mixing solutions of Fe(II) and montmorillonite at pH 3.5. Two different Fe(II)-MMTs were prepared and the ferrous iron contents were 40 mg/L and 80 mg/L. All samples were characterized by XRD, FT-IR, TGA, DSC, and nitrogen adsorption. By nitrogen adsorption, the pore size can be obtained in the pore diameter curve with average pore widths of 6.67 nm, 9.96 nm, and 17.07 nm, respectively. The removal rate of phosphate increased rapidly during the first 40 min, in which Fe(II)-MMT (1) and Fe(II)-MMT (2) were stronger adsorption systems than MMT. The maximum adsorption was 48.38 mg/g …

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Comparative Study Of Solvent Extraction Of Molybdenum By Various Extractants, Abdoul Rachid Chaibou Yacouba, Salmana Laouali Ibrahim, Ibrahim Natatou Jan 2019

Comparative Study Of Solvent Extraction Of Molybdenum By Various Extractants, Abdoul Rachid Chaibou Yacouba, Salmana Laouali Ibrahim, Ibrahim Natatou

Turkish Journal of Chemistry

Solvent extraction of molybdenum from various acid media by Alamine 336, Aliquat 336, TOPO, and DEHPA in kerosene was studied. The extraction efficiency of molybdenum by diisobutyl ketone (DIBK), the effects of various parameters like diluents, mineral acids, extractant concentration, and applications of these extractants on molybdenum extraction contained in the uranium-bearing ore solutions were investigated. DIBK used as solvent can indeed extract the molybdenum without adding any extractants in the range of 20-50 mg/L. Molybdenum was extracted by Aliquat 336 in all mineral acids at more than 90%. On the basis of slope analysis, the compositions of the extracted …

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Synthesis, Characterization, And Kinetic Studies Of Multifunctionalized Mesoporous Silica For Adsorption Of Zinc, Ali̇me Çitak Jan 2019

Synthesis, Characterization, And Kinetic Studies Of Multifunctionalized Mesoporous Silica For Adsorption Of Zinc, Ali̇me Çitak

Turkish Journal of Chemistry

The aim of this study is to evaluate the utilization of bifunctional mesoporous silica with a platinum and propylsulfonic acid group (Pt/SBA15-PrSO$_{3}$H) as an adsorbent for the removal of Zn(II) ions from aqueous solutions. The SBA15-functionalized organosulfonic acid material was synthesized with a one-step cocondensation synthesis route. The second step was Pt loading during reduction and deposition into the aqueous suspension of the bifunctional mesoporous silica synthesized by an aqueous solution of formaldehyde as the reducing agent. The propylsulfonic acid and platinum functionalized mesoporous silica were characterized by BET, thermogravimetric analysis, and X-ray diffraction methods. The adsorption properties and thermodynamic …

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Synthesis Of Highly Active Crystalline Carbon Nitride Prepared In Various Salt Melts For Photocatalytic Degradation Of Phenol, Mohd Hayrie Mohd Hatta, Hendrik Oktendy Lintang, Siew Ling Lee, Leny Yuliati Jan 2019

Synthesis Of Highly Active Crystalline Carbon Nitride Prepared In Various Salt Melts For Photocatalytic Degradation Of Phenol, Mohd Hayrie Mohd Hatta, Hendrik Oktendy Lintang, Siew Ling Lee, Leny Yuliati

Turkish Journal of Chemistry

Crystallinity could have a decisive influence on photocatalytic performance. In this study, the synthesis of crystalline carbon nitride (CN) was studied via an ionic melt polycondensation of urea precursor in the presence of various salt melts, which were KCl-LiCl, KCl-NaCl, and KCl-ZnCl$_{2}$. While all the salt melts helped to improve the optical properties of the CN, only KCl-LiCl salt melt could form crystalline CN as evidenced by its X-ray diffraction pattern. Furthermore, the specific surface area of CN (72 m$^{2}$/g) was maintained when using KCl-LiCl (73 m$^{2}$/g), but it was decreased in the presence of KCl-NaCl (22 m$^{2}$/g) or KCl-ZnCl$_{2}$ …

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Naphthoxazoles And Heterobenzoxazoles: Cholinesterase Inhibition And Antioxidant Activity, Ivana Sagud, Irena Skoric, Franko Burcul Jan 2019

Naphthoxazoles And Heterobenzoxazoles: Cholinesterase Inhibition And Antioxidant Activity, Ivana Sagud, Irena Skoric, Franko Burcul

Turkish Journal of Chemistry

Finding novel cholinesterase inhibitors that would be able to cross the blood--brain barrier, have favorable pharmacokinetic parameters, and reduce hepatotoxicity along with other side effects has been the main focus of investigations dealing with Alzheimer disease. In this study we evaluated cholinesterase inhibitory and antioxidant activity of seven oxazole derivatives. These compounds have been efficiently and sustainably prepared by photochemical electrocyclization reaction. Various naphthoxazoles have been previously investigated as potential antibacterial, antituberculosis, and anticancer agents. They have also been tested for antioxidant activity, but never for cholinesterase inhibitory activity. Among the tested oxazole derivatives, fused heterobenzoxazole compounds with pyridine and …

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1,2-Dibromotetrachloroethane: An Efficient Reagent For Many Transformations By Modified Appel Reaction, Selçuk Eşsi̇z, Ari̇f Daştan Jan 2019

1,2-Dibromotetrachloroethane: An Efficient Reagent For Many Transformations By Modified Appel Reaction, Selçuk Eşsi̇z, Ari̇f Daştan

Turkish Journal of Chemistry

An efficient and facile method has been developed for the synthesis of alkyl bromides from various alcohols under mild conditions using a triphenylphosphine (PPh$_{3})$/1,2-dibromotetrachloroethane (DBTCE) complex in excellent yields and very short time (5 min). This method can also be applied for the transformation of chiral alcohols to their corresponding bromides in very high enantiomeric excess. The PPh$_{3}$/DBTCE complex is also successfully applied to ring-opening reactions of cyclic ethers in mild conditions. Esterification, amidation, and formation of acid anhydrides under very mild experimental conditions are also successfully accomplished by following a modification of the Appel reaction protocol in this work.

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Gold-Assembled Silica-Coated Cobalt Nanoparticles As Efficient Magnetic Separation Units And Surface-Enhanced Raman Scattering Substrate, Lütfi̇ye Sezen Yildirim, Murat Kaya, Mürvet Volkan Jan 2019

Gold-Assembled Silica-Coated Cobalt Nanoparticles As Efficient Magnetic Separation Units And Surface-Enhanced Raman Scattering Substrate, Lütfi̇ye Sezen Yildirim, Murat Kaya, Mürvet Volkan

Turkish Journal of Chemistry

Magnetic and optical bifunctional nanoparticles that combine easy separation, preconcentration, and efficient SERS capabilities have been fabricated with high sensitivity and reproducibility through a low-cost method. These gold nanoparticles attached on magnetic silica-coated cobalt nanospheres (Co@SiO$_{2}$/AuNPs) display the advantage of strong resonance absorption due to gaps at nanoscale between neighboring metal nanoparticles bringing large field enhancements, known as "hot spots". The prepared particles can be controlled by using an external magnetic field, which makes them very promising candidates in biological applications and Raman spectroscopic analysis of dissolved organic species. The magnetic property of the prepared particles lowers the detection limits …

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Computational Investigation Of Influenza A Virus M2 Protein Inhibition Mechanism By Ion Channel Blockers, Mehmet Özbi̇l Jan 2019

Computational Investigation Of Influenza A Virus M2 Protein Inhibition Mechanism By Ion Channel Blockers, Mehmet Özbi̇l

Turkish Journal of Chemistry

The M2 protein of the influenza A virus, responsible for flu, is a homotetramer transmembrane protein, forming a transmembrane ion channel, where His 37s act as pH sensors and Trp 41s and Asp 44s act as channel gates. Opening of this channel leads to transfer of virus RNA into the human host. Thus, blocking this transfer is an important pharmaceutical strategy to stop infection. As a result of viral drug resistance, commercially available channel inhibitors, rimantadine (RIM) and amantadine (AMA), are not as effective as they used to be. Understanding binding sites and outcomes of binding will lead to new …

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New Diazo-Containing Phenolic Oximes: Structural Characterization, Computational Studies, And Solvent Extraction Of Cu(Ii), Ni(Ii), And Zn(Ii) Ions, Muharrem Karabörk, Hi̇lal Kirpik, Koray Sayin, Muhammet Köse Jan 2019

New Diazo-Containing Phenolic Oximes: Structural Characterization, Computational Studies, And Solvent Extraction Of Cu(Ii), Ni(Ii), And Zn(Ii) Ions, Muharrem Karabörk, Hi̇lal Kirpik, Koray Sayin, Muhammet Köse

Turkish Journal of Chemistry

In the current study, four new phenolic oxime ligands (HL1ox-HL4ox) containing diazo groups (-N$=$N-) were synthesized and used for liquid-liquid extraction of heavy metal ions [Cu(II), Ni(II), and Zn(II)]. The new compounds were characterized by analytical and spectroscopic methods. Solid-state structures of HL1ox-HL3ox were determined by single-crystal X-ray diffraction studies. Hirshfeld surface analysis of the compounds was performed to determine the contribution of different intermolecular contacts to the stability of the structures. The HL1ox-HL4ox ligands showed higher extraction performance for Cu(II) ion than Ni(II) and Zn(II) ions. The effect of pH on extraction capacity was investigated and the oxime compounds …

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Preparation Of $\Alpha $-Hydroxyphenylacetic Acid With Cyclodextrins As An Effective Phase-Transfer Catalyst And Its Reaction Mechanism, Bing Ren Tian, Rui Xia Zhang, Hui Min Chu, Qing Huang, Zhi Zhong Wang Jan 2019

Preparation Of $\Alpha $-Hydroxyphenylacetic Acid With Cyclodextrins As An Effective Phase-Transfer Catalyst And Its Reaction Mechanism, Bing Ren Tian, Rui Xia Zhang, Hui Min Chu, Qing Huang, Zhi Zhong Wang

Turkish Journal of Chemistry

An effective procedure for the synthesis of $\alpha $-hydroxyphenylacetic acid with cyclodextrin (CD) catalysts was developed. The phase-transfer catalyst types, catalyst loadings, reaction times, reaction temperatures, and substrate molar ratios were investigated to optimize the reaction conditions. In addition, the factors that affect the reaction were studied, and the relationship between benzaldehyde and $\beta $-cyclodextrin ($\beta $-CD) was analyzed through 2D-ROESY. The equilibrium constant when $\beta $-CD was used as the catalyst was calculated. The results indicated that $\beta $-CD is the optimal catalyst for the reported reaction (yield: 69.08%). Furthermore, the mechanism underlying the reported reaction was proposed.

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Crystal Structure And Hirshfeld Surface Analysis Of 1,2-Ethylene-Bis (Para-Methyl Pyridinium) Dichromate As A New Selective And Mild Agent In Oxidation Of Alcohols, Mostafa Gholizadeh, Mehrdad Pourayoubi, Mohammad Reza Houssiendokht, Hadi Amiri Rudbari, Masoumeh Farimaneh, Anahid Saneei, Giuseppe Bruno Jan 2019

Crystal Structure And Hirshfeld Surface Analysis Of 1,2-Ethylene-Bis (Para-Methyl Pyridinium) Dichromate As A New Selective And Mild Agent In Oxidation Of Alcohols, Mostafa Gholizadeh, Mehrdad Pourayoubi, Mohammad Reza Houssiendokht, Hadi Amiri Rudbari, Masoumeh Farimaneh, Anahid Saneei, Giuseppe Bruno

Turkish Journal of Chemistry

1,2-Ethylene-bis(para-methyl pyridinium) dichromate, (C$_{14}$H$_{18}$N$_{2})$[Cr$_{2}$O$_{7}$], is used as a new oxidizing agent in conversion of some alcohols to their corresponding carbonyl compounds in CH$_{3}$CN solvent and also under solvent-free conditions. In both procedures, high conversion percentages are observed. However, a much shorter reaction time is achieved in solvent-free conditions. For allylic alcohols, the C=C bond is not oxidized and the examined saturated alcohol in this work (i.e. cyclo-hexanol) remains intact, which illustrates the mild nature of reagent used. The structure of the reagent is investigated by single-crystal X-ray diffraction analysis. The C--H$\cdots$O and O$\cdots \pi$ interactions are the most important features …

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Characterization And Purification Of 1,2,4-Triazole-Containing Phthalocyanines Synthesized By Microwave Method And Structure Elucidation By Spectroscopic Techniques, Asi̇ye Nas, Ümi̇t Demi̇rbaş, Nurhan Gümrükçüoğlu, Hali̇t Kanteki̇n Jan 2019

Characterization And Purification Of 1,2,4-Triazole-Containing Phthalocyanines Synthesized By Microwave Method And Structure Elucidation By Spectroscopic Techniques, Asi̇ye Nas, Ümi̇t Demi̇rbaş, Nurhan Gümrükçüoğlu, Hali̇t Kanteki̇n

Turkish Journal of Chemistry

The complexes of peripherally tetra-substituted metal-free (8), lead(II) 9), and zinc(II) (10) phthalocyanine derivatives were synthesized for the first time in this work. The structures of these new complex compounds have been elucidated using many spectral methods such as electronic absorption, FT-IR, $^{1}$H NMR, $^{13}$C NMR, elemental analysis, and mass spectra. The thermogravimetric behavior of compounds 8-10 was determined by thermogravimetric analysis method in addition to these spectral methods.

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3d-Qsar/Hqsar-Based Analysis Of Bioconcentration And Molecular Modification Of Monophenyl Aromatic Compounds, Qing Li, Wenwen Gu, Yu Li Jan 2019

3d-Qsar/Hqsar-Based Analysis Of Bioconcentration And Molecular Modification Of Monophenyl Aromatic Compounds, Qing Li, Wenwen Gu, Yu Li

Turkish Journal of Chemistry

Comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) of three-dimensional quantitative structure-activity relationship (3D-QSAR) models were conducted using 36 aromatic compound congeners as the training set and eight aromatic compound congeners as the test set. Logarithms of experimental bioconcentration data (logBCF) were used as dependent variables and the physicochemical properties of the aromatic compound congeners were used as independent variables. Furthermore, the molecular holographic quantitative structure--activity relationship (HQSAR) model constructed by the HQSAR module in Sybyl software was used to establish a method to find molecular activity substitution sites of bioconcentration potential by coupling the molecule …

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Investigation Of The Structural And Physicochemical Requirements Of Quinoline-Arylamidine Hybrids For The Growth Inhibition Of K562 And Raji Leukemia Cells, Vesna Rastija, Marijana Jukic, Teuta Opacak-Bernardi, Luka Krstulovic, Ivana Stolic, Ljubica Glavac-Obrovac, Miroslav Bajic Jan 2019

Investigation Of The Structural And Physicochemical Requirements Of Quinoline-Arylamidine Hybrids For The Growth Inhibition Of K562 And Raji Leukemia Cells, Vesna Rastija, Marijana Jukic, Teuta Opacak-Bernardi, Luka Krstulovic, Ivana Stolic, Ljubica Glavac-Obrovac, Miroslav Bajic

Turkish Journal of Chemistry

Quantitative structure-activity relationship (QSAR) analysis of 28 quinoline-arylamidine (CQArA) hybrids against two leukemia cells, K562 and Raji, was performed. Multiple linear regression (MLR) models were obtained by genetic algorithm. The best models involved the following descriptors: radial distribution function (RDF) descriptors, GETAWAY (GEometry, Topology, and Atom-Weights AssemblY) descriptor, bond information content index, and dipole moment. The best MLR models for K562 and Raji cells demonstrated satisfactory stability in internal and external validation. Since the QSAR model for Raji cells has better predictive ability, two new highly potent CQArA analogues were proposed based on it. The QSAR models revealed important physicochemical …

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Plasma Polymerized Linalool (Pplin): An Antimicrobial And Biocompatible Coating, Kenan Çakmak, Özkan Bayram, Kübra Solak, Güzi̇n Kaban, Önder Şi̇mşek, Ahmet Mavi̇ Jan 2019

Plasma Polymerized Linalool (Pplin): An Antimicrobial And Biocompatible Coating, Kenan Çakmak, Özkan Bayram, Kübra Solak, Güzi̇n Kaban, Önder Şi̇mşek, Ahmet Mavi̇

Turkish Journal of Chemistry

Bacterial infections in medical devices and drug resistance of bacteria can cause chaos in the world due to loss of lives in addition to the cost of device revisions, quarantine, disinfection of infected areas, and patient treatment. Antibacterial coatings of essential oils on medical devices can prevent bacterial attachment and reduce costs. Linalool is an antibacterial constituent of essential oils. Herein, we examine for the first time the fabrication and characterization of radio frequency (RF) plasma polymerized hydrophilic thin films from linalool (ppLin) by varying deposition parameters (RF power and deposition time) and the behavior of ppLin with two bacteria …

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New Flavonoid Glycosides Conjugates: Synthesis, Characterization, And Evaluation Of Their Cytotoxic Activities, Sawssen Souiei, Fatima Bousejra-El Garah, Mohamed Amine Belkacem, Mansour Znati, Jalloul Bouajila, Hichem Ben Jannet Jan 2019

New Flavonoid Glycosides Conjugates: Synthesis, Characterization, And Evaluation Of Their Cytotoxic Activities, Sawssen Souiei, Fatima Bousejra-El Garah, Mohamed Amine Belkacem, Mansour Znati, Jalloul Bouajila, Hichem Ben Jannet

Turkish Journal of Chemistry

A series of novel halogenated 3-hydroxyflavones (3HFs) were prepared by reacting halogenated hydroxyacetophenones with the appropriate aromatic aldehyde. Glycosylation of 3HFs with acetobromoglucose and deprotection of the acetyl protective groups afforded the desired 3-$O$-flavonoids glycosides in satisfactory yields. All the prepared compounds were tested for their cytotoxic activity against HCT-116, MCF-7, and OVCAR-3 human cancer cell lines. The 3HFs exhibited higher cytotoxic activities compared with the glycosylated flavonoids. Overall, the structure-activity relationship study showed that the introduction of glycoside moiety at the C-3 OH position does not improve the bioactivity.

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Biodegradability Study Of Polypropylene Fibers Blended With Disposable Recycled Poly(Lactic Acid) Plastic Flakes, Mohammad Ali Tavanaie, Abolfazl Mahmudi Gevari Jan 2019

Biodegradability Study Of Polypropylene Fibers Blended With Disposable Recycled Poly(Lactic Acid) Plastic Flakes, Mohammad Ali Tavanaie, Abolfazl Mahmudi Gevari

Turkish Journal of Chemistry

Polymer blending as an efficient method for blending at least two~polymers is usually used to create new materials with desirable physical properties. This article focuses on the biodegradability evaluation of polypropylene (PP) fibers modified with disposable recycled poly(lactic acid) (r-PLA) plastic flakes. Biodegradable modified PP fibers containing 30% r-PLA were prepared by melt spinning process and evaluated with different methods of biodegradation assays. The soil burial test method, CO$_{2}$ evolution analysis, weight loss, mechanical properties, and average molecular weight measurements and analysis of surface morphological changes were performed for biodegradability evaluation of the modified PP fibers. Surface morphology of the …

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Why Protein Conformers In Molecular Dynamics Simulations Differ From Their Crystal Structures: A Thermodynamic Insight, Fi̇li̇ppo Pullara, Mao Wenzhi, Mert Gür Jan 2019

Why Protein Conformers In Molecular Dynamics Simulations Differ From Their Crystal Structures: A Thermodynamic Insight, Fi̇li̇ppo Pullara, Mao Wenzhi, Mert Gür

Turkish Journal of Chemistry

Conformers generally deviate structurally from their starting X-ray crystal structures early in molecular dynamics (MD) simulations. Studies have recognized such structural differences and attempted to provide an explanation for and justify the necessity of MD equilibrations. However, a detailed explanation based on fundamental physics and validation on a large ensemble of protein structures is still missing. Here we provide the first thermodynamic insights into the radically different thermodynamic conditions of crystallization solutions and conventional MD simulations. Crystallization solution conditions can lead to nonphysiologically high ion concentrations, low temperatures, and crystal packing with strong specific protein--protein interactions, not present under physiological …

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Investigation Of The Ideal Composition Of Metal Hexacyanocobaltates With High Water Oxidation Catalytic Activity, Ferdi̇ Karadaş Jan 2019

Investigation Of The Ideal Composition Of Metal Hexacyanocobaltates With High Water Oxidation Catalytic Activity, Ferdi̇ Karadaş

Turkish Journal of Chemistry

The electrocatalytic activities of Prussian blue analogues (PBAs) have recently received much attention due to their robustness and efficiency. Considering that PBAs with hexacyanocobaltate building block stand forward among other PBAs, a systematic study on a family of metal hexacyanocobaltates is presented in this study. Metal hexacyanocobaltates (M $=$ Co, Mn, Ni, and Fe) were prepared, characterized, and electrochemical studies were performed. A series of mixed-metal cobalt-iron hexacyanocobaltates has also been studied to determine the ideal composition of a metal hexacyanocobaltate for electrocatalytic water oxidation process. The overall study clearly indicates that cobalt hexacyanocobaltate exhibits the highest electrocatalytic activity among …

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Spectrophotometric Methods For The Determination Of Fluoride Ion Using Indole-3-Acetic Acid Interaction With Iron(Iii), Emi̇ne İlknur Öztürk, Adnan Kenar, Mehmet Levent Aksu, Mustafa Taşteki̇n Jan 2019

Spectrophotometric Methods For The Determination Of Fluoride Ion Using Indole-3-Acetic Acid Interaction With Iron(Iii), Emi̇ne İlknur Öztürk, Adnan Kenar, Mehmet Levent Aksu, Mustafa Taşteki̇n

Turkish Journal of Chemistry

This study is related to the determination of fluoride ion by the conversion of pink-colored Fe(III) and indole-3-acetic acid (IAA) into a colorless hexafluoride ferrite complex with the addition of fluoride. The optimum conditions of the complex formation were found to be pH 1.7 and a temperature of 60 $^{\circ}$C C. The maximum absorption wavelength of the complex and the detection limit of the method were 525 nm and 0.26 mg/L, respectively. The interfering effects of the different cations (Ag$^{+}$, Al$^{3+}$, Ba$^{2+}$, Ca$^{2+}$, Cd$^{2+}$, Co$^{2+}$, Cu$^{2+}$, K$^{+}$, Mg$^{2+}$, Na$^{+}$, Ni$^{2+}$, Pb$^{2+})$ and anions (SO$_{4}^{2-}$, SO$_{3}^{2-}$, NO$_{2}^{-}$, I$^{-}$, Br$^{-}$, Cl$^{-}$, SCN$^{-}$, …

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Acid-Activated Clay As Heterogeneous And Reusable Catalyst For The Synthesis Of Bioactive Cyclic Ketal Derivatives, Wided Hagui, Rym Essid, Sondes Amri, Nadia Fares, Mohamed Khabbouchi, Olfa Tabbene, Ferid Limam, Ezzedine Srasra, Neji Besbes Jan 2019

Acid-Activated Clay As Heterogeneous And Reusable Catalyst For The Synthesis Of Bioactive Cyclic Ketal Derivatives, Wided Hagui, Rym Essid, Sondes Amri, Nadia Fares, Mohamed Khabbouchi, Olfa Tabbene, Ferid Limam, Ezzedine Srasra, Neji Besbes

Turkish Journal of Chemistry

A new heterogeneous acid catalyst based on a natural resource, Tunisian clay (Clay-H0.5), has been prepared and characterized by FT-IR, FE-SEM, and powder X-ray diffraction (XRD), as well as chemical composition, cation exchange capacity, specific surface area, and pore volume. Acid treatment for 0.5 h enlarged the surface area from 78.24 to 186.10 m$^{2}$/g and pore volume (PV) from 0.186 to 0.281 cm$^{3}$/g. The catalytic activity of this material was investigated in ketalization reaction under mild solvent-free conditions. This achieved up to 92% isolated yield for only 10 wt.% of the catalyst. This environmentally friendly method has advantages such as …

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Boric Acid As An Efficient And Green Catalyst For The Synthesis Of 2-Amino-4,6-Diarylnicotinonitrile Under Microwave Irradiation In Solvent-Free Conditions, Zahra Hosseinzadeh, Ali Ramazani, Nima Razzaghi-Asl, Katarzyna Slepokura, Tadeusz Lis Jan 2019

Boric Acid As An Efficient And Green Catalyst For The Synthesis Of 2-Amino-4,6-Diarylnicotinonitrile Under Microwave Irradiation In Solvent-Free Conditions, Zahra Hosseinzadeh, Ali Ramazani, Nima Razzaghi-Asl, Katarzyna Slepokura, Tadeusz Lis

Turkish Journal of Chemistry

Microwave irradiation has been used to improve the one-pot synthesis of substituted 2-amino-4,6-diarylnicoti- nonitrile in the presence of boric acid as an efficient and green catalyst under solvent-free conditions within 48--60 s. All the analogs that have not been reported previously were characterized by their melting points, IR, $^{1}$H NMR, and $^{13}$C NMR spectra. One of the structures was verified by the analysis of a single crystal. The reported synthetic procedure provided remarkable advantages such as short reaction times, excellent yield, facile workup, and the use of a green catalyst.

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Organotemplate-Free Cs-Abw Nanozeolite As Highly Reactive And Recyclable Catalyst For Henry Reaction Between Benzaldehyde And Nitroethane, Tamara Mahmoud Ali Ghrear, Ka Lun Wong, Soon Huat Tan, Tau Chuan Ling, Hussein Awala, Engpoh Ng Jan 2019

Organotemplate-Free Cs-Abw Nanozeolite As Highly Reactive And Recyclable Catalyst For Henry Reaction Between Benzaldehyde And Nitroethane, Tamara Mahmoud Ali Ghrear, Ka Lun Wong, Soon Huat Tan, Tau Chuan Ling, Hussein Awala, Engpoh Ng

Turkish Journal of Chemistry

Zeolite Cs-ABW nanocatalyst has been hydrothermally synthesized without using any harmful organic template. The zeolite nanocrystal with very high solid yield (81.88%) can be obtained within 60 min and at 180 $^{\circ}$C (∼ 20 atm), conditions that are much faster and gentler than the existing synthesis methods. The orthorhombic Cs-ABW nanocrystals (mean size of 32 nm) have high aluminum content (Si/Al ratio $=$ 1.14) and possess high basicity. The nanocrystals also exhibit better catalytic activity than conventional homogeneous catalysts in the Henry (nitroaldol) reaction of benzaldehyde with nitroethane under microwave heating conditions. The nanocatalyst does not suffer from coking and …

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