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Articles 31 - 60 of 694
Full-Text Articles in Physical Sciences and Mathematics
On The Contribution Of The 6.7 Kev Line Emission Of The Algol Binary System To The 6.7 Kev Line Emission From The Galactic Ridge, Ambrose Chukwudi Eze, Romanus Nwachukwu Chijioke Eze, Sudum Esaenwi
On The Contribution Of The 6.7 Kev Line Emission Of The Algol Binary System To The 6.7 Kev Line Emission From The Galactic Ridge, Ambrose Chukwudi Eze, Romanus Nwachukwu Chijioke Eze, Sudum Esaenwi
Turkish Journal of Physics
We carried out spectroscopic analysis of the extracted stellar flare of the Algol binary system observed using the Suzaku satellite (OBSID: 401093010), and resolved a strong 6.7 keV line emission. The 6.7 keV line emission of the Algol binary system is similar to the 6.7 keV line of the galactic ridge X-ray emission (GRXE). The equivalent width (EW) compared favorably with the EW of the 6.7 keV emission line obtained from different galactic ridge regions. In the galaxy, we have a reasonable number of Algol binary systems and many other stars as strong coronal X-ray emitters characterized by frequent quiescent …
The Milne Problem Using The P$_{N}$ Method For A Nonabsorbing Medium With Linearly Anisotropic Scattering, Mustafa Çeti̇n Güleçyüz, Ahmet Ersoy
The Milne Problem Using The P$_{N}$ Method For A Nonabsorbing Medium With Linearly Anisotropic Scattering, Mustafa Çeti̇n Güleçyüz, Ahmet Ersoy
Turkish Journal of Physics
The Milne problem, known as one of the classical problems of radiative transfer and neutron transport theory, is solved using the P$_{N}$ method for a nonabsorbing medium (c = 1) with a linearly anisotropic scattering kernel. Specular and diffuse reflection boundary conditions are taken into account. The numerical results are listed for different selected parameters. Some results are also compared with the literature.
Annealing And Deposition Time Effects On The Structural, Optical, And Electrical Properties Of Indium Sulfide Thin Films Produced By Chemical Bath Deposition Method, Emi̇ne Güneri̇, Fatma Göde
Annealing And Deposition Time Effects On The Structural, Optical, And Electrical Properties Of Indium Sulfide Thin Films Produced By Chemical Bath Deposition Method, Emi̇ne Güneri̇, Fatma Göde
Turkish Journal of Physics
Indium sulfide thin films were deposited onto indium-doped tin-oxide substrates with different deposition times (60 h, 63 h, 66 h, and 69 h) at room temperature by using a chemical bath deposition method to obtain new structures for solar cells. The film obtained at 60 h was annealed at 400 $^{\circ}$C for 1 h in nitrogen media. The crystallographic structure of the films was observed via the X-ray diffraction pattern while the size and shape of the grains were characterized by scanning electron microscopy. Moreover, the optical transmission spectra of the films were obtained at room temperature in the wavelength …
Lime: Semiautomated Line Measurement And Identification From Stellar Spectra, Ti̇mur Şahi̇n
Lime: Semiautomated Line Measurement And Identification From Stellar Spectra, Ti̇mur Şahi̇n
Turkish Journal of Physics
We present LIME (Line Measurements from ECHELLE Spectra), an IDL-based code, as a powerful tool for semiautomated stellar line measurement and identification. Interactively selected line positions (i.e. wavelengths) are compared with a master line list of the user's selections. Each unknown line that the user interactively chooses is displayed with potential identifications provided by the code in the vicinity of the selected line. The best identification is evaluated on the basis of several criteria (e.g., atomic/molecular line information, wavelength displacement, and theoretical equivalent width for solar atmospheric values). We examined the identifications by LIME in the spectra of post-red supergiant …
Influence Of Silicon Dioxide Medium On The Structural And Electrical Properties Of Nickel Zinc Ferrite, Jacob George, Abraham Kutticheril Eapen
Influence Of Silicon Dioxide Medium On The Structural And Electrical Properties Of Nickel Zinc Ferrite, Jacob George, Abraham Kutticheril Eapen
Turkish Journal of Physics
Nickel zinc ferrite [(Ni$_{0.65}$Zn$_{0.35}$Fe$_{2}$O$_{4}) _{x}$ / (SiO$_{2}) _{1-x}$ where, x = 1.0, 0.85, 0.65, 0.50, 0.35, and 0.15] is synthesized using the glyoxylate precursor method. The synthesis, characterization, and electrical study of nickel zinc ferrites/SiO$_{2}$ powder with low dielectric constant, very low conductivity, and loss tangent with low frequency dispersion, suitable for good insulators, is reported here. X-ray diffraction, TGA, and FT-IR studies are employed for identifying crystalline phases and structure. Crystallite size is calculated by the Scherrer formula and Williamson--Hall equation and found to fall in the range of 4.9--25 nm. TEM of the samples shows spherical particles of …
Second Law Of Gravitational Thermodynamics In The Locally Rotationally Symmetric Bianchi Type-Ii Universe, Murat Korunur
Second Law Of Gravitational Thermodynamics In The Locally Rotationally Symmetric Bianchi Type-Ii Universe, Murat Korunur
Turkish Journal of Physics
In this work, under the assumption that the universe is locally rotationally symmetric (LRS) Bianchi type-II and filled with anisotropic dark fluid (dark energy and dark radiation), we investigate whether the generalized second law of thermodynamics (GSLT) is still valid. We also consider another important condition for LRS Bianchi type-II spacetimes whereby the model expansion $\theta $ is proportional to the shear $\sigma $, which leads to $B=A^{n}$ (where n is a constant and A and B are the metric potentials). Based on this, we derive a general circumstance for the GSLT and find that its validity depends on the …
First-Principles Modeling Of Gan/Mose$_{2}$ Van Der Waals Heterobilayer, Celal Yelgel
First-Principles Modeling Of Gan/Mose$_{2}$ Van Der Waals Heterobilayer, Celal Yelgel
Turkish Journal of Physics
We investigate structural and electronic properties of the graphene-like gallium nitride (GaN) monolayer deposited on a MoSe$_{2}$ monolayer by using density functional theory with the inclusion of the nonlocal van der Waals correction. The GaN is bound weakly to the MoSe$_{2}$ monolayer with adsorption energy of 49 meV/atom. We find that the heterobilayer is energetically favorable with the interlayer distance of 3.302 {\AA} indicating van der Waals (vdW) type interaction and the most stable stacking configuration is verified with different deposition sequences. The heterostructure of GaN/MoSe$_{2}$ is found to be indirect band gap semiconductor with gap value of 1.371 eV. …
Magnetized Strange Quark Matter In Reconstructed $F(R,T)$ Gravity For Bianchi I And V Universes With Cosmological Constant, Can Aktaş
Turkish Journal of Physics
In this article, we have investigated the behaviors of magnetized strange quark matter distributions for Bianchi I and V universes in reconstructed $f?eft( R,T \right)=\alpha_{1}R+\alpha_{2}f_{3}(T)$ gravity (here $\alpha_{1}$ and $\alpha_{2}$ are constants; $f_{3}(T)$ is an arbitrary function of $T)$. To get solutions of the field equations we have used a deceleration parameter and the equation of state for strange quark matter. The new represented $f(R,T)$ model includes two models of Harko et al. and transforms to general relativity. When $t\to ınfty $, we get the dark energy model ($p=-\rho )$ in reconstructed $f?eft( R,T \right)=\alpha _{1}R+\alpha_{2}f_{3}(T)$ gravity. However, we obtain …
Monte Carlo Simulation Of A Medical Linear Accelerator For Filtered And Fff Systems, Çağri Yazğan, Yi̇ği̇t Çeçen
Monte Carlo Simulation Of A Medical Linear Accelerator For Filtered And Fff Systems, Çağri Yazğan, Yi̇ği̇t Çeçen
Turkish Journal of Physics
In order to simulate radiation transport, various algorithms, codes, and programs have been developed. In this study Monte Carlo N-particle code is used to simulate a medical electron linear accelerator gantry for research purposes. Detailed geometry of the LINAC head and water phantom are modeled and simulated for calculations. Analyses are made for filtered and flattening filter-free (FFF) systems. Percent depth dose and dose profile measurements are calculated with Monte Carlo simulations and compared with experimental and theoretical values for quality assurance of the model. Flux, dose, and spectrum analyses are performed for filtered and FFF systems separately. In this …
Analytical Solution Of The Local Fractional Klein-Gordon Equation For Generalized Hulthen Potential, Hasi̇be Hale Karayer, Ahmet Doğan Demi̇rhan, Fevzi̇ Büyükkiliç
Analytical Solution Of The Local Fractional Klein-Gordon Equation For Generalized Hulthen Potential, Hasi̇be Hale Karayer, Ahmet Doğan Demi̇rhan, Fevzi̇ Büyükkiliç
Turkish Journal of Physics
The one-dimensional Klein-Gordon (KG) equation is investigated in the domain of conformable fractional calculus for one-dimensional scalar potential, namely generalized Hulthen potential. The conformable fractional calculus is based on conformable fractional derivative, which is the most natural definition in noninteger order calculus. Fractional order differential equations can be solved analytically by means of this derivative operator. We obtained exact eigenvalue and eigenfunction solutions of the local fractional KG equation and investigated the evolution of relativistic effects in correspondence with the fractional order.
Applying A Self-Feedback Method To Control Chaos In The Buck Converter, Mei Mei Jia
Applying A Self-Feedback Method To Control Chaos In The Buck Converter, Mei Mei Jia
Turkish Journal of Physics
Chaos exists in the Buck converter due to the switching action of the controlled switch and this nonlinear phenomenon results in unreliable working performances. Hence, this paper uses a self-feedback control method with two adjustable parameters to suppress the chaotic behavior in the Buck converter. First, the self-feedback control method is presented by introducing a generic second-order chaotic system. Then, from the perspective of transfer functions obtained in terms of the piecewise linear model of the controlled Buck converter, effects of controller's parameters on system performances are discussed. On the basis of the Jacobian matrix of the discrete iterative mapping …
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 …
Improvement Of Electrochemical And Structural Properties Of Polycarbazole By Simultaneous Electrodeposition Of Chitosan, Di̇dem Balun Kayan, Veysel Polat
Improvement Of Electrochemical And Structural Properties Of Polycarbazole By Simultaneous Electrodeposition Of Chitosan, Di̇dem Balun Kayan, Veysel Polat
Turkish Journal of Chemistry
Polycarbazole/chitosan composite materials were synthesized electrochemically at various loadings of chitosan (Chi). Their electrochemical, structural, thermal, and morphological characterizations were investigated by cyclic voltammetry, chronoamperometry, electrochemical impedance spectroscopy, Fourier transform infrared spectroscopy, thermal gravimetry, and scanning electron microscopy. Further electrical conductivity was measured using a four-point probe technique. The electrochemical results showed that the electrical conductivity of the polymeric composite film was increased by increasing the amount of Chi in the electrolyte medium. The as-prepared composite films exhibited enhanced electrical conductivity and structural properties of polycarbazole due to the presence of Chi in the composite films.
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 …
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 …
Activity Of $\Gamma $-Al$_{2}$O$_{3}$-Based Mn, Cu, And Co Oxide Nanocatalysts For Selective Catalytic Reduction Of Nitric Oxide With Ammonia, Parvaneh Nakhostin Panahi, Gerard Delahay
Activity Of $\Gamma $-Al$_{2}$O$_{3}$-Based Mn, Cu, And Co Oxide Nanocatalysts For Selective Catalytic Reduction Of Nitric Oxide With Ammonia, Parvaneh Nakhostin Panahi, Gerard Delahay
Turkish Journal of Chemistry
Our studies on the selective catalytic reduction of NO (SCR-deNO) properties of M/$\gamma $-Al$_{2}$O$_{3}$ (M = Mn, Co, Cu) nanocatalysts are presented. All catalysts were prepared by homogeneous deposition precipitation using urea as the precursor for the precipitating agent. The SCR activity followed the order Mn/$\gamma $-Al$_{2}$O$_{3} >$ Cu/$\gamma $-Al$_{2}$O$_{3} >$ Co/$\gamma $-Al$_{2}$O$_{3}$. The nanocatalysts were characterized with respect to their texture (N$_{2}$-BET), particle size (TEM), reducibility (H$_{2}$-TPR), and acidity (NH$_{3}$-TPD). The TEM analysis revealed that the metal species have superior dispersion with less agglomeration and sintering on $\gamma $-Al$_{2}$O$_{3}$ support. The H$_{2}$-TPR results confirmed that the Mn/$\gamma $-Al$_{2}$O$_{3}$ nanocatalyst …
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 …
Stereoselective And Regioselective Synthesis Of $N$-Substituted Methyl 2-((Azolyl)Methyl)-3-Arylacrylates From Baylis-Hillman Acetates, Ayşen Köseceli̇ Özenç, İlhami̇ Çeli̇k, Şule Kökten
Stereoselective And Regioselective Synthesis Of $N$-Substituted Methyl 2-((Azolyl)Methyl)-3-Arylacrylates From Baylis-Hillman Acetates, Ayşen Köseceli̇ Özenç, İlhami̇ Çeli̇k, Şule Kökten
Turkish Journal of Chemistry
$N$-Substituted methyl 2-((azolyl)methyl)-3-arylacrylates were synthesized stereo- and regioselectively with one-pot reaction between Baylis--Hillman acetates and a suitable acylazole in the presence of K$_{2}$CO$_{3}$ as a base catalyst. The targeted $N$-substituted azole acrylates were efficiently obtained in good yields (39%-89%).
Development Of A Sample Preparation Strategy For The Determination Of Tungsten In Soil Samples By Inductively Coupled Plasma Mass Spectrometry Using A Response Surface Methodology, Ümran Seven Erdemi̇r
Development Of A Sample Preparation Strategy For The Determination Of Tungsten In Soil Samples By Inductively Coupled Plasma Mass Spectrometry Using A Response Surface Methodology, Ümran Seven Erdemi̇r
Turkish Journal of Chemistry
An alternative rapid digestion method has been developed for the determination of tungsten (W) in soil samples using fractionation studies and response surface methodology. The digestion method using the Kjeldahl instrument was applied to samples, and soluble tungsten was determined via inductively coupled plasma mass spectrometry. Digestion parameters were selected depending on the results of fractionation studies and optimized using a four-factor and five-level central composite design. The contributions of the phosphoric acid concentration (X$_{1})$, digestion temperature (X$_{2})$, digestion time (X$_{3})$, and hydrochloric acid concentration (X$_{4})$ were evaluated for the determination of W from samples in which its levels were …
Efficient Photodegradation Of Neutral Red Chloride Dye In Aqueous Medium Using Graphene/Cobalt-Manganese Oxides Nanocomposite, Khalid Saeed, Idrees Khan
Efficient Photodegradation Of Neutral Red Chloride Dye In Aqueous Medium Using Graphene/Cobalt-Manganese Oxides Nanocomposite, Khalid Saeed, Idrees Khan
Turkish Journal of Chemistry
Graphene/cobalt-manganese oxides nanocomposites were prepared from their precursor through chemical reduction where NaOH was used as a reducing agent. The obtained GNs/Co-Mn nanocomposites were used as photocatalyst for the photodegradation of Neutral Red Chloride (NRC) dye in aqueous solution under sunlight as a function of time and catalyst dosage. The morphology and photodegradation study was carried out using scanning electron microscopy (SEM) and UV-VIS spectrophotometry, respectively. The SEM image showed the presence of Co-Mn nanoparticles on the surface of GNs, which were also confirmed by energy dispersive X-ray analysis. The photodegradation study of NRC showed that the degradation of dye …
Bis(Indoline-2,3-Diones): Versatile Precursors For Novel Bis(Spirooxindoles) Incorporating 4$H$-Chromene-3-Carbonitrile And Pyrano[2,3-$D$]Pyrimidine-6-Carbonitrile Derivatives, Said Ahmed Soliman Ghozlan, Muhammed Aly Ramadan, Amr Mohmed Abdelmoniem, Ahmed H. M. Elwahy, Ismail Abdelshafy Abdelhamid
Bis(Indoline-2,3-Diones): Versatile Precursors For Novel Bis(Spirooxindoles) Incorporating 4$H$-Chromene-3-Carbonitrile And Pyrano[2,3-$D$]Pyrimidine-6-Carbonitrile Derivatives, Said Ahmed Soliman Ghozlan, Muhammed Aly Ramadan, Amr Mohmed Abdelmoniem, Ahmed H. M. Elwahy, Ismail Abdelshafy Abdelhamid
Turkish Journal of Chemistry
Multicomponent reaction of dimedone or 1,3-dimethylbarbituric acid and malononitrile with a series of bis(indoline-2,3-diones) afforded the corresponding bis(2-amino-7,7-dimethyl-2',5-dioxo-5,6,7,8-tetrahydrospiro[chromene-4,3'-indoline]-3-carbonitrile) and bis(7'-amino-1',3'-dimethyl-2,2',4'-trioxo-1',2',3',4'-tetrahydrospiro[indoline-3,5'-pyrano [2,3-d]pyrimidine]-6'-carbonitrile) derivatives in good to excellent yield.
Dehydration Behavior And Kinetics Of Kurnakovite Under Microwave Irradiation, Fatma Tuğçe Şenberber, Meral Yildirim, İkli̇m Nergi̇z Özdoğan, Azmi̇ Seyhun Kipçak, Emek Derun
Dehydration Behavior And Kinetics Of Kurnakovite Under Microwave Irradiation, Fatma Tuğçe Şenberber, Meral Yildirim, İkli̇m Nergi̇z Özdoğan, Azmi̇ Seyhun Kipçak, Emek Derun
Turkish Journal of Chemistry
In this research, the dehydration behavior of kurnakovite was studied under microwave irradiation. The kinetic parameters of the dehydration reaction were determined using different kinetic models. Kurnakovite was characterized by the techniques of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM) before and after the dehydration process. According to the results, kurnakovite was identified as a compound with the powder diffraction file (pdf) number 00-024-0700 before the dehydration process and after the dehydration process amorphous formations were observed. Moreover, FT-IR results showed that dehydration was completed successfully because of the disappearance in the band values …
Microwave-Enhanced Fenton-Like Degradation By Surface-Modified Metal-Organic Frameworks As A Promising Method For Removal Of Dye From Aqueous Samples, Seyed Ershad Moradi, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Saeed Emami
Microwave-Enhanced Fenton-Like Degradation By Surface-Modified Metal-Organic Frameworks As A Promising Method For Removal Of Dye From Aqueous Samples, Seyed Ershad Moradi, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Saeed Emami
Turkish Journal of Chemistry
In the current research, the sulfonated metal-organic framework loaded on iron oxide nanoparticles, Fe$_{3}$O$_{4}$@MIL-100(Fe)-OSO$_{3}$H, has been synthesized and utilized as a Fenton-like catalyst for the decolorization of aqueous solutions containing methyl orange (MO) dye as a model organic pollutant. The morphology and structure of the catalyst were characterized by X-ray powder diffraction, transmission electron microscopy, Brunauer-Emmett-Teller analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, and UV-Vis diffuse reflectance spectroscopy. The effects of various parameters on MO degradation were investigated and the optimum conditions for MO degradation were found to be an initial concentration of MO of 100 mg/L, initial concentration of …
Synthesis Of Neodymium-Iron Nanoperovskite For Sensing Applications Of An Antiallergic Drug, Nada F. Atta, Mohammad H. Binsabt, Ekram H. El-Ads, Ahmed Galal
Synthesis Of Neodymium-Iron Nanoperovskite For Sensing Applications Of An Antiallergic Drug, Nada F. Atta, Mohammad H. Binsabt, Ekram H. El-Ads, Ahmed Galal
Turkish Journal of Chemistry
A facile route was used for the fabrication of NdFeO$_{3}$ (NF) perovskite. The orthorhombic structure of single phase nanocrystalline NdFeO$_{3}$ perovskite was confirmed by different characterization techniques: XRD, FTIR, TEM, BET, SEM, and EDAX. The nanoperovskite was successfully used as a sensor component with a carbon paste electrode (CpE) for the determination of ketotifen in pharmaceutical formulations. Ketotifen, an antiallergic drug, is utilized for the treatment of asthma attacks, rhinitis, skin allergies, and anaphylaxis. Sodium dodecyl sulfate (SDS) was employed in a surface assembly mode to improve the sensitivity of the sensor response. The proposed sensor, NdFeO$_{3}$ in situ modified …
Diastereoselective Synthesis Of Novel 2,5-Dioxopyrrolidine Derivatives Via Biocatalytic Domino Reactions, Saadieh Mohajer, Robabeh Baharfar
Diastereoselective Synthesis Of Novel 2,5-Dioxopyrrolidine Derivatives Via Biocatalytic Domino Reactions, Saadieh Mohajer, Robabeh Baharfar
Turkish Journal of Chemistry
A series of novel 2,5-dioxopyrrolidines were synthesized by the one-pot reaction of coumarin-3-carboxylic acids 1 with thiourea derivatives and alkyl isocyanides in the presence of Fe$_{3}$O$_{4}$ NPs @ lipase as heterogeneous reusable nanobiocatalysts with high yields.
Adsorption Isotherm Modeling Of Carbendazim And Flumetsulam Onto Homoionic-Montmorillonite Clays: Comparison Of Linear And Nonlinear Models, Yassine El Maataoui̇, Mohamadine El M'Rabet, Abdelkrim Maaroufi, Hassan Oudda, Abdelmalek Dahchour
Adsorption Isotherm Modeling Of Carbendazim And Flumetsulam Onto Homoionic-Montmorillonite Clays: Comparison Of Linear And Nonlinear Models, Yassine El Maataoui̇, Mohamadine El M'Rabet, Abdelkrim Maaroufi, Hassan Oudda, Abdelmalek Dahchour
Turkish Journal of Chemistry
This study deals with the adsorption of two pesticides, carbendazim and flumetsulam, from aqueous solutions onto four homoionic-montmorillonite clays (Ag$^{+}$, Zn$^{2+}$, Cu$^{2+}$, and H$^{+})$. Equilibrium adsorption isotherm data were analyzed using Freundlich, Dubinin-Radushkevich, and Temkin isotherms. Linear and nonlinear fitting methods were compared to determine the best-fitting isotherms for the experimental data. Three error analysis methods were used to evaluate the data for each method: the coefficient of determination (R$^{2})$, sum of squared errors (SSE), and chi-square test ($\chi^{2})$. Equilibrium adsorption isotherms exhibited that the carbendazim adsorption mainly involved cation exchange with homoionic-montmorillonite adsorbents. However, for flumetsulam, the main mechanisms …
Online Coupling Electrochemical Preconcentration And Gfaas Technique As Effective Method For Determination Of Ultratrace Concentrations Of Antimony In Groundwater And Surface Water Samples, Lubomir Machynak, Martin Nemecek, Ernest Beinrohr, Frantisek Cacho
Online Coupling Electrochemical Preconcentration And Gfaas Technique As Effective Method For Determination Of Ultratrace Concentrations Of Antimony In Groundwater And Surface Water Samples, Lubomir Machynak, Martin Nemecek, Ernest Beinrohr, Frantisek Cacho
Turkish Journal of Chemistry
The present article describes a method of determination of low antimony concentrations using a graphite furnace AAS technique after electrochemical preconcentration. A 2-electrode flow-through cell was developed with a working electrode made of gold-coated porous carbon and an accessory Pt electrode. This cell worked in online coupling with the graphite furnace atomizer. Accumulation occurred from the 6 M hydrochloric acid solution and 2 M nitric acid was used to dissolve and transport antimony into the sampling loop. The sampling loop was placed on a 6-way valve. The preconcentrated solution was transported to the atomizer using an air jet. The detection …
Synchrotron X-Ray Diffraction Studies Of $\Beta $-Ca$_{2-X}M_{X}$Sio$_{4}$ ($M$ = Mg And Sr), Anti Prodjosantoso, Brendan Kennedy
Synchrotron X-Ray Diffraction Studies Of $\Beta $-Ca$_{2-X}M_{X}$Sio$_{4}$ ($M$ = Mg And Sr), Anti Prodjosantoso, Brendan Kennedy
Turkish Journal of Chemistry
The structures of Mg- and Sr-doped $\beta $-Ca$_{2}$SiO$_{4}$ have been established from high-resolution synchrotron X-ray powder diffraction. These silicates are all isostructural and the structures have been refined in the monoclinic space group, $P$2$_{1}$/$n$. As expected based on size arguments, the cell parameters increase as the amount of Sr increases and likewise decrease as the amount of Mg increases due the size effects of the dopant cation. In all cases the SiO$_{4}$ tetrahedra are essentially regular.