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Articles 9841 - 9870 of 15564
Full-Text Articles in Entire DC Network
Graphene-Like 2-D Nanomaterials And Their Properties, Diana Daikie Aggudey
Graphene-Like 2-D Nanomaterials And Their Properties, Diana Daikie Aggudey
Theses, Dissertations and Culminating Projects
Graphene, unlike other carbon allotropes has recently been the subject of interest in the field of nano material research. Graphene is being utilized as the building block for graphitic materials such as the 0-D fullerenes, 1-D nanotubes and 3-D graphites. Graphene is a single layer material, made up of interconnected hexagons of sp bonded carbon atoms arranged in a honeycomb crystal lattice. Graphene and its derivatives have been shown in previous studies/research to exhibit exceptional high electronic and thermal conductivity, optical transparency and high specific surface area additional to outstanding mechanical flexibility and environmental stability. Graphene is amongst the most …
High-Level Expression Of The Brugia Malayi Protein Kinase, Bm-Mpk 1, In Insect Sf9 Cells, Arti Rana
High-Level Expression Of The Brugia Malayi Protein Kinase, Bm-Mpk 1, In Insect Sf9 Cells, Arti Rana
Theses, Dissertations and Culminating Projects
Lymphatic Filariasis (elephantiasis) is a neglected tropical disease caused by the filarial nematodes Brugia malayi (B. malayi), Brugia timori, and Wuchererici Bancrofti (1,8). These parasites are present in over 83 counties in the tropics and sub-tropics where more than 1.4 billion people are at risk of infection and 130 million people are presently infected (1,7). Previous work from our lab has led to the identification and expression of a B. malayi stress-activated protein kinase, Bm-MPKl (a human p38/C. elegans PMK-1 ortholog). Bm-MPKl plays an important role in the parasites’ protection against oxidative stress (1), and as such is a potential …
Monitoring Ligand-Induced Nucleic Acid Conformational Changes Using Ion Mobility Spectrometry-Mass Spectrometry, Bill Kenneth Redick
Monitoring Ligand-Induced Nucleic Acid Conformational Changes Using Ion Mobility Spectrometry-Mass Spectrometry, Bill Kenneth Redick
Legacy Theses & Dissertations (2009 - 2024)
Three-dimensional structures of biopolymers frequently dictate the biological role those molecules play. As such, investigation into structure of nucleic acids can provide important information pertaining to how those nucleic acids work. Many nucleic acid species, especially single-stranded RNA, fold into unique structures that allow them to function properly. Metals, and other cationic species, are often bound to the nucleic acid to make folding into the proper structure more favorable by neutralizing the negative charge on the nucleic acid imparted by the phosphate group. This investigation explores tertiary structure of nucleic acids that have been folded in the presence of ligands …
Modeling The Early, Aging-Related Changes In Human Recombinant Gammas-Crystallin In Vitro, Christiana Oluwaseun Salami
Modeling The Early, Aging-Related Changes In Human Recombinant Gammas-Crystallin In Vitro, Christiana Oluwaseun Salami
Legacy Theses & Dissertations (2009 - 2024)
Cataract is the leading cause of blindness in the world. Cataractous lenses scatter a significant part of the light entering the eye. Cataract can be of several types: Age-related cataract, secondary cataract, traumatic cataract, congenital cataract, and radiation cataract. Age-related cataract is the most common type of cataract. Several factors contribute to age-onset cataract; among them are the Post-Translational Modifications (PTMs) to the major lens proteins or crystallins, which constitute about 80-90% of the protein content of the lens. Predominant PTMs of the crystallins are oxidation, deamidation, phosphorylation, glycation, and disulfide crosslinking, which tend to increase as the lens ages.
First-Principles Study Of The Electric Field Effect On The Water-Adsorbed Rutile Titanium Dioxide Surface, Abraham L. Hmiel
First-Principles Study Of The Electric Field Effect On The Water-Adsorbed Rutile Titanium Dioxide Surface, Abraham L. Hmiel
Legacy Theses & Dissertations (2009 - 2024)
TiO2 is a semiconducting material that has been used extensively in many industrial applications, and recently has become a candidate for photocatalytic water splitting, fuel cell anode support materials, sensors, and other novel nanodevices. The interface of TiO2 with water, historically well-studied but still poorly understood, presents a ubiquitous environmental challenge towards the ultimate practical usefulness of these technologies. Ground-state density functional theory (DFT) calculations studying the characteristics of molecular adsorption on model surfaces have been studied for decades, showing constant improvement in the description of the energetics and electronic structure at interfaces. These simulations are invaluable in the …
Improving The Microbial Source Tracking Toolbox : Evaluating The Use Of Selective Enrichments And Artificial Sweeteners In A Multi-Tiered Approach, Stacey A. Helming
Improving The Microbial Source Tracking Toolbox : Evaluating The Use Of Selective Enrichments And Artificial Sweeteners In A Multi-Tiered Approach, Stacey A. Helming
Legacy Theses & Dissertations (2009 - 2024)
Microbial contamination of surface waters is a public health concern world-wide, with non-point source fecal input contributing to millions of cases of waterborne illness annually. Numerous techniques have been proposed to monitor for non-point source fecal contamination, but few studies have explored the correlation of multiple chemical and microbial fecal source tracking markers in ambient waters. Therefore, the purpose of these studies was to evaluate the use of multiple "ideal" markers of fecal contamination and improve upon any analytical techniques required to identify species-specific fecal contamination in surface waters. The use of selective enrichments to improve the sensitivity of end-point …
Analysis Of Mass Fragmentation Patterns Using Dart-Ms And Gcms For Drugs Of Abuse, Teresa Anne O'Neill
Analysis Of Mass Fragmentation Patterns Using Dart-Ms And Gcms For Drugs Of Abuse, Teresa Anne O'Neill
Legacy Theses & Dissertations (2009 - 2024)
Drugs of abuse have been a major problem for law enforcement departments. The structures of the drugs, as well as the ever changing trends in abuse, make it difficult and time consuming to analyze using modern techniques such as GC-MS. DART-MS is a rapid technique that requires no pre-treatment or re-concentration to analyze a sample. Samples of amphetamines, cathinones and cannabinoids were analyzed using DART-MS and GC-MS in order to provide fragment patterns that would make it easier to identify an unknown drug. Using DART-MS, isomers can be differentiated as well as identified rapidly, which is an advantage over GC-MS. …
Raman Spectroscopy Of Blood Serum And Cerebrospinal Fluid And Multivariate Data Analysis For Alzheimer's Disease Diagnostics, Elena Ryzhikova
Raman Spectroscopy Of Blood Serum And Cerebrospinal Fluid And Multivariate Data Analysis For Alzheimer's Disease Diagnostics, Elena Ryzhikova
Legacy Theses & Dissertations (2009 - 2024)
The efficient and accurate diagnosis at the early stages of dementia is a key moment for effective treatment and productive research to find a new ways to combat the disease. It is especially true for Alzheimer's disease (AD) for which there is no effective cure, but several treatments are known to allow slowing down the degenerative processes. Alzheimer's disease (AD) displays only non-specific clinical symptoms of mental decline for decades after the initiation and is very challenging to differentiate even at the later stages when it becomes very aggressive. Despite the great need, current diagnostic tests are unable to diagnose …
Uncovering Organosulfur Natural Products In The "Shy-Plant" Mimosa Pudica Via Direct Analysis In Real Time Mass Spectrometry : Volatiles Emission From Touch Sensitive Roots, Max Jacob Maron
Legacy Theses & Dissertations (2009 - 2024)
Mimosa pudica L. (Mimosaceae) is a small shrub endemic to South America, now pantropically distributed. M. pudica displays the properties of seismonasty where the leaves fold and stems droop in response to both touch, as well as nyctinasty, a type of circadian rhythm. It was previously reported that the principal component of the odor that is produced when M. pudica is uprooted is caused by CS2 and COS, both of which were detected by GC-MS. The present study has found that the roots emit a foul odor in response to direct root stimulation. Further, neither CS2 nor COS were observed …
Quantification Of Free Sialic Acid In Human Plasma Through A Robust Quinoxalinone Derivatization And Lc–Ms/Ms Using Isotope-Labeled Standard Calibration, Dan Wang, Xiang Zhou, Lin Wang, Sihe Wang, Xue-Long Sun
Quantification Of Free Sialic Acid In Human Plasma Through A Robust Quinoxalinone Derivatization And Lc–Ms/Ms Using Isotope-Labeled Standard Calibration, Dan Wang, Xiang Zhou, Lin Wang, Sihe Wang, Xue-Long Sun
Chemistry Faculty Publications
We report an accurate quantification of free sialic acid (SA) in human plasma using LC–MS/MS method with isotope-labeled standard calibration (ILSC) and robust derivatization. Specifically, derivatization of SA with a stable and inexpensive 3,4-diaminotoluene (DAT) provides a stable product of SA with high MS response, proving a convenient and cost-effective LC–MS/MS analysis of free SA. In addition, the use of 13C3-SA as calibration standard ensured the accuracy for the measurement. This assay used ultra high performance liquid chromatography (UHPLC) for separation of native/labeled SA and IS from matrix interference, and employed mass spectrometry in multiple reaction monitoring …
Comparison Of Chelating Ability Of No-, Ns-, Ons-, And Ono-Type Schiff Base Derivatives And Their Stability Constants Of Bis-Complexes With Copper(Ii), Hasan Atabey, Esra Findik, Hayati̇ Sari, Mustafa Ceylan
Comparison Of Chelating Ability Of No-, Ns-, Ons-, And Ono-Type Schiff Base Derivatives And Their Stability Constants Of Bis-Complexes With Copper(Ii), Hasan Atabey, Esra Findik, Hayati̇ Sari, Mustafa Ceylan
Turkish Journal of Chemistry
The present study includes important findings relating to the number of donor atoms, species of ligands, and stabilities of complexes. Stabilities of complexes between Cu(II) ion and NO-, NS-, ONS-, and ONO-type Schiff bases were compared. Acid-base properties of the Schiff bases were explained at 25 \pm 0.1 °C and ionic strength (I) of 0.1 M supported by NaCl. The Hyperquad computer program was used for calculation of dissociation and stability constants. The overall stability constants of their Cu(II) complexes were calculated and the various formed complexes between the Schiff bases with Cu(II) ion formulated as CuL_2, CuHL_2, CuH_2L_2, and …
On The Peculiar Reactivity Of A C,N-Annelated Isoindole Core, Iaroslav Baglai, Valerie Maraval, Zoia Vsevolodivna Voitenko, Carine Duhayon, Yulian Mihailovich Volovenko, Remi Chauvin
On The Peculiar Reactivity Of A C,N-Annelated Isoindole Core, Iaroslav Baglai, Valerie Maraval, Zoia Vsevolodivna Voitenko, Carine Duhayon, Yulian Mihailovich Volovenko, Remi Chauvin
Turkish Journal of Chemistry
C-, N-, and/or O-methylation products were generated from 11H-isoindolo[2,1-a]quinazoline-5-one upon treatment with NaH followed by iodomethane under air, and possible recrystallization from methanol. Two products were fully characterized by NMR and X-ray diffraction analysis. In accordance with the HSAB principle, this soft methylating agent (MeI) leads mainly to the C,C-dimethylated product 11,11-dimethyl-11H-isoindolo[2,1-a]quinazoline-5-one, which was previously not observed, beside the N-methylated product, in a procedure using methyl tosylate as a hard methylating agent of the same substrate in the initial absence of a base. A mechanism is finally proposed for the formation of methyl 2-(3-methyl-4-oxo-3,4-dihydroquinazolin-2-yl)benzoate as an oxidation side product.
Synthesis, Biological Evaluation, And Molecular Docking Of N'-(Aryl/Alkylsulfonyl)-1-(Phenylsulfonyl) Piperidine-4-Carbohydrazide Derivatives, Hira Khalid, Aziz Ur Rehman, Muhammad Athar Abbasi, Rashad Hussain, Khalid Mohammad Khan, Muhammad Ashraf, Syeda Abida Ejaz, Muhammad Qaiser Fatmi
Synthesis, Biological Evaluation, And Molecular Docking Of N'-(Aryl/Alkylsulfonyl)-1-(Phenylsulfonyl) Piperidine-4-Carbohydrazide Derivatives, Hira Khalid, Aziz Ur Rehman, Muhammad Athar Abbasi, Rashad Hussain, Khalid Mohammad Khan, Muhammad Ashraf, Syeda Abida Ejaz, Muhammad Qaiser Fatmi
Turkish Journal of Chemistry
A series of new N'-[(alkyl/aryl)sulfonyl]-1-(phenylsulfonyl)piperidine-4-carbohydrazide derivatives were synthesized. Starting from ethyl piperidine-4-carboxylate (a), first ethyl 1-(phenylsulfonyl)piperidine-4-carboxylate (1), second 1-(phenylsulfonyl)piperidine-4-carbohydrazide (2), and finally N'-[(alkyl/aryl)sulfonyl]-1-(phenylsulfonyl)piperidine-4-carbohydrazides (4a--n) were synthesized by reacting 2 with alkyl/aryl sulfonyl chlorides (3a--n). The structures of the synthesized compounds were characterized by IR, ^1H-NMR, and EI-MS spectra and all were screened in vitro for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzyme inhibition activities. Molecular docking was accomplished for these compounds to examine their binding interactions with AChE and BChE human proteins. The strategy we applied for this purpose was a direct receptor-based approach. The binding modes of the inhibitors …
Fluorescence Quenching Study Of Moxifloxacin Interaction With Calf Thymus Dna, Yunkai Lv, Pan Li, Miao-Lun Jiao, Bao-Sheng Liu, Chao Yang
Fluorescence Quenching Study Of Moxifloxacin Interaction With Calf Thymus Dna, Yunkai Lv, Pan Li, Miao-Lun Jiao, Bao-Sheng Liu, Chao Yang
Turkish Journal of Chemistry
Moxifloxacin (MOX) is a fourth-generation synthetic fluoroquinolone antibacterial agent with many important therapeutic properties. Fluorescence quenching was used to study the interaction of MOX with calf thymus DNA (ct-DNA) in aqueous solution. The intercalative binding mode and a static quenching mechanism were confirmed by the Stern--Volmer quenching rate constant (K_q) of 3.48 \times 10^{11} M^{-1} s^{-1} at 298 K. The thermodynamic parameters (\Delta H = --118.4 KJ mol^{-1} and \Delta S = --299.4 J mol^{-1} K^{-1}) were calculated at different temperatures, and they indicate that the main forces between MOX and ct-DNA are hydrogen bonding and Van der Waals force. …
Study Of The Interaction Between Glucosamine Hydrochloride And Sodium Dodecylsulphate Micelles Using Conductometric, Isothermal Calorimetry, Zeta-Potential Titrations, And Nmr Noesy, Marcos Roberto Abreu Alves, Luciano Sindra Virtuoso, Elson Santiago De Alvarenga, Ângelo Márcio Leite Denadai
Study Of The Interaction Between Glucosamine Hydrochloride And Sodium Dodecylsulphate Micelles Using Conductometric, Isothermal Calorimetry, Zeta-Potential Titrations, And Nmr Noesy, Marcos Roberto Abreu Alves, Luciano Sindra Virtuoso, Elson Santiago De Alvarenga, Ângelo Márcio Leite Denadai
Turkish Journal of Chemistry
The aim of this work was to investigate the influence of an anti-inflammatory agent, the bulky counterion named glucosamine (Gl^+), in sodium dodecylsulphate (SDS) in 2 ways: 1) by titration of SDS solutions with different concentrations of Gl^+; and 2) by titration of Gl^+ with SDS solution with concentration close to the critical micellar concentration (cmc) (7.7 mM). In procedure 1, micellisation study by isothermal titration calorimetry (ITC) showed that the increase in Gl^+ concentration reduces the cmc and the micellisation enthalpy. Increasing of the micellisation entropy was also observed, suggesting desolvation of micellar structures as a consequence of electrostatic …
Aryl Butenoic Acid Derivatives As A New Class Of Histone Deacetylase Inhibitors: Synthesis, In Vitro Evaluation, And Molecular Docking Studies, Peruze Ayhan Eşi̇yok, Özlem Seven, Gülüzar Eymur, Gamze Bora Tatar, Di̇dem Dayangaç Erden, Kemal Yelekçi̇, Hayat Yurter, Ayhan Sitki Demi̇r
Aryl Butenoic Acid Derivatives As A New Class Of Histone Deacetylase Inhibitors: Synthesis, In Vitro Evaluation, And Molecular Docking Studies, Peruze Ayhan Eşi̇yok, Özlem Seven, Gülüzar Eymur, Gamze Bora Tatar, Di̇dem Dayangaç Erden, Kemal Yelekçi̇, Hayat Yurter, Ayhan Sitki Demi̇r
Turkish Journal of Chemistry
New aryl butenoic acid derivatives have been synthesized by combining hydroxy- or methoxy-substituted phenyl rings as the capping group, with a double bond in the short linker as well as metal binding groups, enoic ester, and salts bearing either methyl or morpholine. These compounds have been shown to possess promising histone deacetylase inhibition activities via in vitro fluorometric assay and molecular docking studies.
Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani
Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani
Turkish Journal of Chemistry
This review gives an overview of the application of guanidine and its salts in multicomponent reactions. It can act as a catalyst or solvent for multicomponent reactions or as a reagent for synthesis of substituted diazines, triazines, and macroheterocycles by multicomponent reactions.
Deposition And Characterization Of Cu_9s_5 Nanocrystals From Unsymmetrical [(Hex)(Me)Nc(S)Nc(O)C_6h_3(No_2)_2-3,5]_2cu(Ii) And [(Et)(Bu)Nc(S)Nc(O)C_6h_4-4-No_2]_2cu(Ii) Complexes By Colloidal Thermolysis Method, Sohail Saeed, Rizwan Hussain
Deposition And Characterization Of Cu_9s_5 Nanocrystals From Unsymmetrical [(Hex)(Me)Nc(S)Nc(O)C_6h_3(No_2)_2-3,5]_2cu(Ii) And [(Et)(Bu)Nc(S)Nc(O)C_6h_4-4-No_2]_2cu(Ii) Complexes By Colloidal Thermolysis Method, Sohail Saeed, Rizwan Hussain
Turkish Journal of Chemistry
Cu_9S_5 nanocrystals were synthesized from unsymmetrical [(Hex)(Me)NC(S)NC(O)C_6H_3(NO_2)_2-3,5]_2Cu(II) and [(Et)(Bu)NC(S)NC(O)C_6H_4-4-NO_2]_2 Cu(II) complexes by colloidal thermolysis in the presence of surfactant oleylamine. The unsymmetrical copper complexes were synthesized by the reaction of copper(II) acetate with N-[hexyl(methyl)carbamothioyl]-3,5-dinitrobenzamide and N-[ethyl(butyl)carbamothioyl]-4-nitrobenzamide. The complexes were used as single-source precursors for the preparation of Cu_9S_5 nanocrsytals. The Cu_9S_5 nanocrystals were characterized by X-ray powder diffraction and transmission electron microscopy.
Facile Synthesis Of 5-Bromotropono[C]-Fused Pyrazoles And Isoxazole, Yang Li, Liangyu Xu, Wentao Gao
Facile Synthesis Of 5-Bromotropono[C]-Fused Pyrazoles And Isoxazole, Yang Li, Liangyu Xu, Wentao Gao
Turkish Journal of Chemistry
A facile synthesis of a series of new 5-bromotropono[c]pyrazole derivatives (3 and 10--15) as well as 5-bromotropono[c]isoxazole (17) is described, involving a condensation reaction of 3-acetyl-5-bromotropolone (1) with hydrazine monohydrate (2), arylhydrazine hydrochlorides (4--9), and hydroxylamine hydrochloride (16), respectively. All the synthesized compounds were obtained in good yields of 56%--77% and their structures were characterized by spectral data and HRMS.
Selective Oxidation Of Sulfides And Hydrocarbons With H_2o_2 Over Manganese Catalyst Supported On Nanoparticles, Massomeh Ghorbanloo, Roghayeh Tarasi, Jun Tao, Hidenori Yahiro
Selective Oxidation Of Sulfides And Hydrocarbons With H_2o_2 Over Manganese Catalyst Supported On Nanoparticles, Massomeh Ghorbanloo, Roghayeh Tarasi, Jun Tao, Hidenori Yahiro
Turkish Journal of Chemistry
A new magnetically separable catalyst consisting of binuclear Mn(II) complex [Mn_2(HL)_2(H_2O)_4], HL = 2-[(2-hydroxy-benzylidene)-amino]-3-(4-hydroxyphenyl)-propionic acid, supported on (3-chloropropyl)-trimethoxysilane (CPTMS) functionalized silica-coated magnetic nanoparticles (MNPs) was prepared. The synthesized catalyst was characterized by several physico-chemical and spectroscopic methods. This immobilized complex was found to be an efficient heterogeneous catalyst for the oxidation of different sulfides and hydrocarbons using hydrogen peroxide (H_2O_2) as an oxidant. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no considerable loss of catalytic activity.
Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei
Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei
Turkish Journal of Chemistry
The adsorption of the urea molecule on the external surface of the B_{12}N_{12} nanocage was investigated using density functional theory (DFT) calculations. Adsorption of urea on the nanocage releases energies of about --23.70 to --29.50 kcal/mol with a significant NBO charge transfer from the urea to the nanocage. It was also found that the urea molecule can be strongly chemisorbed on the surface of the nanocage with Gibbs free energies of -7.91 to -14.81 kcal/mol. The HOMO--LUMO gap of the nanocage does not change significantly upon urea adsorption, while the Fermi level is dramatically changed from -4.27 eV in the …
Partial Purification And Biochemical Characterization Of An Extremely Thermo- And Ph-Stable Esterase With Great Substrate Affinity, Esra Özbek, Yakup Kolcuoğlu, Leyla Konak, Ahmet Çolak, Fulya Öz
Partial Purification And Biochemical Characterization Of An Extremely Thermo- And Ph-Stable Esterase With Great Substrate Affinity, Esra Özbek, Yakup Kolcuoğlu, Leyla Konak, Ahmet Çolak, Fulya Öz
Turkish Journal of Chemistry
An esterase from a thermophilic bacterium, Geobacillus sp. DF20, was partially purified. Final purification factor was found to be 64.5-fold using Q-Sepharose ion exchange column chromatography. Native polyacrylamide gel electrophoresis indicated the presence of a single active esterase. The substrate specificity of this esterase was high for p-nitrophenyl butyrate (pNPB) substrate. The optimum pH and temperature for the enzyme activity were 7.0 and 50 ^°C, respectively. The pH and heat stability profiles show that this enzyme is more stable under neutral conditions at 50 ^°C. K_m and V_{max} values for this esterase acting on pNPB were 0.12 mM and 54.6 …
Organic Biomolecules Bind To Phosphate Through Borate Linkages In Aqueous Solutions, Nazi̇k Aydoğmuş, Dursun Ali̇ Köse, Michael Andrew Beckett, Bi̇rgül Karan
Organic Biomolecules Bind To Phosphate Through Borate Linkages In Aqueous Solutions, Nazi̇k Aydoğmuş, Dursun Ali̇ Köse, Michael Andrew Beckett, Bi̇rgül Karan
Turkish Journal of Chemistry
Solutions of salicyclic, ascorbic, and citric acids were reacted with boric acid, followed by NaH_2PO_4. The products, triphosphateborate ester of salicylic acid (1), orthosphateborate ester of ascorbic acid (2), triphosphateborate ester of ascorbic acid (3), and orthosphateborate ester of citric acid (4), were flash precipitated with cold acetone and characterised by microanalysis, thermal analysis, FT-IR, Raman, ^{11}B NMR, ^{31}P MAS NMR, and mass spectroscopic techniques. Analytical results indicated the presence of --C--O--B--O--P-- linkages with the attached phosphate groups varying between orthophosphate and triphosphate, depending on the starting material. The biomolecules studied in this work may serve as models in the …
Poly(Vinyl Chloride) Functionalization By Aliphatic And Aromatic Amines: Application To The Extraction Of Some Metal Cations, Fayçel Ammari, Faouzi Meganem
Poly(Vinyl Chloride) Functionalization By Aliphatic And Aromatic Amines: Application To The Extraction Of Some Metal Cations, Fayçel Ammari, Faouzi Meganem
Turkish Journal of Chemistry
The aim of this study was to evaluate the efficiency of 3 new polymers obtained by functionalization of a commercial poly(vinyl chloride) by grafting amino-alkyl and amino-aryl groups to extract some metal cations from aqueous solutions. The percentage of extraction was determined by comparing the initial electrical conductivity of the aqueous solution containing the studied metal and that of the aqueous solution at the extraction equilibrium. One of the obtained polymers gave an extraction ratio of Sn^{2+} = 87.1 %, which highlight the importance of the substitution of chlorine atoms by diethylenetriamine groups. These results were compared with those obtained …
Thermal Conversion Of Glycerol To Value-Added Chemicals: Pyridine Derivatives By One-Pot Microwave-Assisted Synthesis, Duygu Bayramoğlu, Gökay Gürel, Ali̇ Sinağ, Mustafa Güllü
Thermal Conversion Of Glycerol To Value-Added Chemicals: Pyridine Derivatives By One-Pot Microwave-Assisted Synthesis, Duygu Bayramoğlu, Gökay Gürel, Ali̇ Sinağ, Mustafa Güllü
Turkish Journal of Chemistry
One-pot syntheses of the value-added heterocyclic compounds 3-methylpyridine and pyridine using a renewable chemical, glycerol, were achieved in acidic medium by thermal conversion reactions. Condensation/cyclization reactions of the thermal degradation products of glycerol were investigated in situ using different ammonia and acidic moiety producing inorganic ammonium salts under pyrolysis or microwave heating conditions. The reaction parameters were studied in detail and satisfying product yields up to 72 % were obtained under optimized conditions. Structural identification of all compounds was accomplished by spectroscopic methods.
Linear Assembly And 3d Networks Of Peptide Modified Gold Nanoparticles, Şaban Kalay, Clement Blanchet, Mustafa Çulha
Linear Assembly And 3d Networks Of Peptide Modified Gold Nanoparticles, Şaban Kalay, Clement Blanchet, Mustafa Çulha
Turkish Journal of Chemistry
The charge and size of molecules chemically attached to nanoparticles (NPs) play an important role in their interaction behavior in suspensions. Gold nanoparticles (AuNPs) were modified systematically with peptides and the modification was verified with surface-enhanced Raman scattering (SERS). The behavior of the modified AuNPs in suspension and at the liquid--solid interface was monitored using small angle X-ray scattering (SAXS), UV/Vis spectroscopy and dynamic light scattering (DLS) in suspension, and atomic force microscopy (AFM) at the solid--liquid interface. It was found that while negatively charged peptide modified AuNPs behave very similar to citrate reduced AuNPs due to their negatively charged …
Graphene Oxide--Magnetite Nanocomposite As An Efficient And Magnetically Separable Adsorbent For Methylene Blue Removal From Aqueous Solution, Kadem Meral, Önder Meti̇n
Graphene Oxide--Magnetite Nanocomposite As An Efficient And Magnetically Separable Adsorbent For Methylene Blue Removal From Aqueous Solution, Kadem Meral, Önder Meti̇n
Turkish Journal of Chemistry
We report a facile method to produce a magnetically separable graphene oxide--magnetite nanocomposite (GO--Fe_3O_4) and its adsorption performance in methylene blue (MB) removal from aqueous solution. The GO--Fe_3O_4 nanocomposite was synthesized by a solution-phase self-assembly method including the incorporation of monodisperse Fe_3O_4 nanoparticles (NPs) and GO in a dimethylformamide/chloroform mixture under sonication. The successfully decorating GO sheet with monodisperse Fe_3O_4 NPs was proved by TEM study. ICP--OES data of the GO--Fe_3O_4 nanocomposite show that the GO--Fe_3O_4 nanocomposite consists of 21 wt% Fe_3O_4 NPs, which is sufficient for its magnetic separation from aqueous solution. The spectroscopic studies reveal that the GO--Fe_3O_4 …
Synthesis, Anticandidal Activity, And Cytotoxicity Of Some Thiazole Derivatives With Dithiocarbamate Side Chains, Leyla Yurttaş, Yusuf Özkay, Fati̇h Demi̇rci̇, Gamze Göger, Şafak Ulusoylar Yildirim, Usama Abu Mohsen, Ömer Öztürk, Zafer Asim Kaplancikli
Synthesis, Anticandidal Activity, And Cytotoxicity Of Some Thiazole Derivatives With Dithiocarbamate Side Chains, Leyla Yurttaş, Yusuf Özkay, Fati̇h Demi̇rci̇, Gamze Göger, Şafak Ulusoylar Yildirim, Usama Abu Mohsen, Ömer Öztürk, Zafer Asim Kaplancikli
Turkish Journal of Chemistry
Some thiazole derivatives bearing dithiocarbamic acid esters were synthesized in order to investigate their anticandidal activity and cytotoxicity. The structures of the obtained final compounds (6a--j) were confirmed by spectral data (IR, ^1H NMR, ^{13}C NMR, and MS) and elemental analysis. The anticandidal activity of the compounds was determined (6a--j) using the microbroth dilution method and their cytotoxicity was evaluated according to the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay against normal cells. Contrary to expectations, weak antifungal activity was observed with IC_{50} values ranging between 30 and 403 \mu g/mL.
Convenient Method For Synthesis Of Various Fused Heterocycles Via Utility Of 4-Acetyl-5-Methyl-1-Phenyl-Pyrazole As Precursor, Sobhi Mohamed Gomha, Ahmad Sami Shawali, Abdou Osman Abdelhamid
Convenient Method For Synthesis Of Various Fused Heterocycles Via Utility Of 4-Acetyl-5-Methyl-1-Phenyl-Pyrazole As Precursor, Sobhi Mohamed Gomha, Ahmad Sami Shawali, Abdou Osman Abdelhamid
Turkish Journal of Chemistry
A new, less expensive, solvent-free procedure was developed for the synthesis of some new derivatives of various fused heterocyclic ring systems, namely azolopyridazine, azolotriazine, azinotriazine, thienopyridine, and pyrazolopyridine. The structures of the products prepared were established by their spectral data and elemental analyses. Eight compounds were evaluated for their in vitro antimicrobial activity. Some of the tested compounds exhibited moderate to significant antibacterial and antifungal activities.
Synthesis Of Tertiary Propargylic Phosphonates By Addition Of Trialkynylaluminum Reagents To Acyl Phosphonates And Investigation Of Their Antimicrobial Activities, Muhammed Shakhawoat Hossain, Sidika Polat Çakir, Ayşe Betül Karaduman, Mustafa Yamaç, Ayhan Sitki Demi̇r
Synthesis Of Tertiary Propargylic Phosphonates By Addition Of Trialkynylaluminum Reagents To Acyl Phosphonates And Investigation Of Their Antimicrobial Activities, Muhammed Shakhawoat Hossain, Sidika Polat Çakir, Ayşe Betül Karaduman, Mustafa Yamaç, Ayhan Sitki Demi̇r
Turkish Journal of Chemistry
A series of propargylic alcohols containing phosphonates was synthesized by addition reactions of tris-(propynyl) and tris-(phenylethynyl)aluminum reagents to acyl phosphonates in good yields. Aromatic moieties of the acyl phosphonates with electron-withdrawing groups generally resulted in better isolated chemical yield. Selected propargylic phosphonates were tested for antimicrobial activities. Compounds 3a and 3h showed noticeable antifungal activity, especially against molds.