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Geochemical, Microthermometric, And Isotopic Constraints On The Origin Of Fluorite Deposits In Central Anatolia, Turkey, Peli̇n Coşanay, Ece Kirat, Ni̇hal Çevi̇k, Ceyda Kizilkanat, Hali̇m Mutlu, Şükrü Koç
Geochemical, Microthermometric, And Isotopic Constraints On The Origin Of Fluorite Deposits In Central Anatolia, Turkey, Peli̇n Coşanay, Ece Kirat, Ni̇hal Çevi̇k, Ceyda Kizilkanat, Hali̇m Mutlu, Şükrü Koç
Turkish Journal of Earth Sciences
We investigate rare earth element geochemistry, microthermometric characteristics, and radiogenic isotope systematics of fluorites and stable isotope compositions of gangue minerals from several fluorite deposits in central Turkey. In the deposits, fluorite is the main ore mineral and it is accompanied by quartz, calcite, and minor pyrite and barite. Veins are represented by three different fluorite types based on their color. Total REY contents of fluorites are highly variable, ranging from 24 to 693 ppm. LREE concentrations of fluorites of all colors are similar but medium and heavy REE abundances of green fluorites are nearly an order of magnitude greater …
Paleoenvironment Of The Late Oligocene From The Kağızman-Tuzluca Basin (Northeastern Anatolia) Based On The Micro- And Macrofloras, Mi̇ne Sezgül Kayseri̇ Özer, Recep Hayretti̇n Sancay, Şevket Şen, Koray Sözeri̇, Gregoire Métais, Turhan Ayyildiz, Baki̇ Erdoğan Varol
Paleoenvironment Of The Late Oligocene From The Kağızman-Tuzluca Basin (Northeastern Anatolia) Based On The Micro- And Macrofloras, Mi̇ne Sezgül Kayseri̇ Özer, Recep Hayretti̇n Sancay, Şevket Şen, Koray Sözeri̇, Gregoire Métais, Turhan Ayyildiz, Baki̇ Erdoğan Varol
Turkish Journal of Earth Sciences
The Kağızman-Tuzluca Basin in East Anatolia is still poorly documented for its stratigraphy and in particular its paleofloral assemblages. In this study, the microfloras from the Kağızman-Kötek and Kömürlü areas and the macroflora from the Tuzluca area in this basin have been defined to overcome this deficiency. Sedimentary sequences of the Kağızman-Kömürlü area have been deposited in terrestrial conditions different from the sequences of the Kağızman-Kötek and Tuzluca areas, which were deposited in brackish conditions near a shallow marine environment. Paleovegetation in eastern Anatolia is represented by mixed mesophytic and coniferous forests restricted to high and middle altitudes (e.g. Pinus, …
The Discovery Of A Low-Angle Normal Fault In The Taurus Mountains: The İvriz Detachment And Implications Concerning The Cenozoic Geology Of Southern Turkey, Gürol Seyi̇toğlu, Veysel Işik, Esra Gürbüz, Alper Gürbüz
The Discovery Of A Low-Angle Normal Fault In The Taurus Mountains: The İvriz Detachment And Implications Concerning The Cenozoic Geology Of Southern Turkey, Gürol Seyi̇toğlu, Veysel Işik, Esra Gürbüz, Alper Gürbüz
Turkish Journal of Earth Sciences
The İvriz detachment fault has been determined on the southern border of the Ulukışla basin separating the metamorphic Bolkar Group of the Taurus Mountains and the Paleocene-Lower Eocene Halkapınar formation of basin deposits. The fault dips towards the north and has kinematic indicators (asymmetric grain/grain aggregate porphyroclasts, oblique foliation, and S-C fabrics), suggesting a top-to-the-N-NE sense of shearing. The clastic material originating from the Bolkar Group in the sedimentary units of the Ulukışla basin demonstrates that the detachment fault could have been be active during Latest Cretaceous-Eocene times. The İvriz detachment may have initiated as part of a high-angle breakaway …
The Impact Of Eustasy, Tectonics, And Paleoclimate On The Dolomitization Of The Syn-Rift Neogene Carbonate Platforms In The Red Sea Coastal Area, Egypt, Abdallah Mohammed Hassan
The Impact Of Eustasy, Tectonics, And Paleoclimate On The Dolomitization Of The Syn-Rift Neogene Carbonate Platforms In The Red Sea Coastal Area, Egypt, Abdallah Mohammed Hassan
Turkish Journal of Earth Sciences
A very significant quantity of dolomites and dolomitic limestones of variable origins occurs in the syn-rift Neogene carbonate platforms of the NW Red Sea coast and the Gulf of Suez. These are more common in the Um Diheisi Member of the Ranga Formation (early Miocene), the Um Mahara Formation (middle Miocene), the Um Gheig Formation (late Miocene), and the Dashet El Dabaa Member of the Shagra Formation (Pliocene). Based on their stratigraphic distribution, petrography, and cathodoluminescent characteristics, as supported by geochemical data, syn-rift irregular morphotectonic relief, and the eustasy, four distinct types of dolomites have been identified and were interpreted …
Crustal S-Wave Structure Around The Lake Van Region (Eastern Turkey) From Interstation Rayleigh Wave Phase Velocity Analyses, Hakan Çinar, Hamdi̇ Alkan
Crustal S-Wave Structure Around The Lake Van Region (Eastern Turkey) From Interstation Rayleigh Wave Phase Velocity Analyses, Hakan Çinar, Hamdi̇ Alkan
Turkish Journal of Earth Sciences
This study focuses on the average crustal and the upper mantle structure throughout the Lake Van region of eastern Turkey. The study aimed to investigate the structure with the fundamental mode interstation Rayleigh wave phase velocities from the local and the regional earthquakes recorded by Kandilli Observatory and Earthquake Research Institute stations. Considering back azimuth differences of each source and station path, six different broadband station pairs and 27 earthquakes were selected to determine the 1-D shear-wave velocity structures throughout the region by using an interstation method (slant stacking technique). The linearized least squares algorithm was used to obtain the …
Marine Effects On Vertical Electrical Soundings Along Shorelines, Emi̇n Uğur Ulugergerli̇
Marine Effects On Vertical Electrical Soundings Along Shorelines, Emi̇n Uğur Ulugergerli̇
Turkish Journal of Earth Sciences
Onshore applications of direct current resistivity (DCR) along shorelines suffer a short-circuit-like phenomenon due to electrical current flowing through a more conductive body of water rather than ground. Our study of the numerical simulation of DCR data with a three-dimensional forward model demonstrated that the apparent resistivity was reduced as a function of the sea depth and the distance of measurement site to the shoreline. Furthermore, it was concluded that the "marine effects" on DCR data (i.e. reduction in apparent resistivity) become nonnegligible as the ratio of half-electrode expansion (AB/2) to the distance to the shoreline is larger than one. …
Active Faults In The Anatolian-Aegean Plate Boundary Region With Nubia, Ali̇ Değer Özbakir, Rob Govers, Rinus Wortel
Active Faults In The Anatolian-Aegean Plate Boundary Region With Nubia, Ali̇ Değer Özbakir, Rob Govers, Rinus Wortel
Turkish Journal of Earth Sciences
Convergence of the Africa, Arabia, and Eurasia plates and the westward escape of Anatolia have resulted in an evolving plate boundary zone in the Eastern Mediterranean. The current location and nature of the plate boundary between the Anatolian and the African plate is difficult to trace due to the scattered crustal earthquakes and the absence of deep ones. We examine various types and locations for the plate boundary as constrained by seismicity, seismic reflection studies, tomographic studies, and geodetic measurements and we use a spherical plane stress finite element model to test these possibilities. In our regional model, we impose …
Maastrichtian-Thanetian Planktonic Foraminiferal Biostratigraphy And Remarks On The K-Pg Boundary In The Southern Kocaeli Peninsula (Nw Turkey), Volkan Sarigül, Aynur Hakyemez, Okan Tüysüz, Şengül Can Genç, İsmai̇l Ömer Yilmaz, Ercan Özcan
Maastrichtian-Thanetian Planktonic Foraminiferal Biostratigraphy And Remarks On The K-Pg Boundary In The Southern Kocaeli Peninsula (Nw Turkey), Volkan Sarigül, Aynur Hakyemez, Okan Tüysüz, Şengül Can Genç, İsmai̇l Ömer Yilmaz, Ercan Özcan
Turkish Journal of Earth Sciences
The Kocaeli Peninsula (NW Turkey) provides one of the best exposed deep marine Upper Cretaceous-Palaeocene sections in north-western Anatolia. The biostratigraphic framework from three sections, namely Belen, Bulduk, and Toylar, in the southern part of the Kocaeli Peninsula is established by means of planktonic foraminifera. A very rich planktonic foraminiferal assemblage analysed both in thin sections and washed residues records a biozonation ranging from the Contusotruncana contusa (CF6) Zone (Maastrichtian) to the Globanomalina pseudomenardii (P4) Zone (Thanetian). Although a major part of the biozones in the studied interval is clearly defined, the upper three zones (CF1-3) of the latest Maastrichtian …
Sulfur Isotope Characteristics Of The Permian Vhms Deposits In Tasik Chini District, Central Belt Of Peninsular Malaysia, Mohd Basril Iswadi Basori, Khin Zaw, Robert Ross Large, Wan Fuad Wan Hassan
Sulfur Isotope Characteristics Of The Permian Vhms Deposits In Tasik Chini District, Central Belt Of Peninsular Malaysia, Mohd Basril Iswadi Basori, Khin Zaw, Robert Ross Large, Wan Fuad Wan Hassan
Turkish Journal of Earth Sciences
Sulfur isotope data from sulfide and sulfate minerals have been measured from the two typical examples of the Permian volcanic-hosted massive sulfide (VHMS) deposits at the Tasik Chini district in the Central Belt of Peninsular Malaysia. In this study, we present the sulfur isotope data for 33 sulfide minerals and 23 barite samples from two VHMS deposits in the Tasik Chini district. Sulfides show a narrow range of sulfur values from -2.9%o to +8.30%o, which can be interpreted to be derived from a mixed sulfur source of reduced seawater sulfate with the possible addition of magmatic sulfur. Sulfate sulfur in …
Suborbital Graphs For The Atkin-Lehner Group, Tuncay Köroğlu, Bahadir Özgür Güler, Zeynep Şanli
Suborbital Graphs For The Atkin-Lehner Group, Tuncay Köroğlu, Bahadir Özgür Güler, Zeynep Şanli
Turkish Journal of Mathematics
We investigate suborbital graphs for an imprimitive action of the Atkin-Lehner group on a maximal subset of extended rational numbers on which a transitive action is also satisfied. Obtaining edge and some circuit conditions, we examine some combinatorial properties of these graphs.
Topological Entropies Of A Class Of Constrained Systems, Yanni Ma, Bingzhe Hou
Topological Entropies Of A Class Of Constrained Systems, Yanni Ma, Bingzhe Hou
Turkish Journal of Mathematics
In this paper, we consider a class of constrained systems named double upper bounds $(p,q)$-constrained systems ($(p,q)$-DUB systems in brief), which are one-dimensional subshifts of finite type. We determinate the topological entropies (Shannon capacities) $C(p,q)$ of all $(p,q)$-DUB systems and consequently order all $(p,q)$-DUB systems according to the size of topological entropies. In particular, $C(p, \infty)=C(p+1, p+1)$ are the only equalities possible among the topological entropies of $(p,q)$-DUB systems.
$\Mathcal{Vw}$-Gorenstein Complexes, Renyu Zhao, Wei Ren
$\Mathcal{Vw}$-Gorenstein Complexes, Renyu Zhao, Wei Ren
Turkish Journal of Mathematics
Let $\mathcal{V,W}$ be two classes of modules. In this paper, we introduce and study $\mathcal{VW}$-Gorenstein complexes as a common generalization of $\mathcal{W}$-complexes, Gorenstein projective (resp., Gorenstein injective) complexes, and $G_C$-projective (resp., $G_C$-injective) complexes. It is shown that under certain hypotheses a complex $X$ is $\mathcal{VW}$-Gorenstein if and only if each $X^n$ is a $\mathcal{VW}$-Gorenstein module. This result unifies the corresponding results of the aforementioned complexes. As an application, the stability of $\mathcal{VW}$-Gorenstein complexes is explored.
Generalized $\Ast$-Lie Ideal Of $\Ast$-Prime Ring, Seli̇n Türkmen, Neşet Aydin
Generalized $\Ast$-Lie Ideal Of $\Ast$-Prime Ring, Seli̇n Türkmen, Neşet Aydin
Turkish Journal of Mathematics
Let $R$ be a $\ast$-prime ring with characteristic not $2,$ $\sigma, \tau:R\rightarrow R$ be two automorphisms, $U$ be a nonzero $\ast$-$\left( \sigma,\tau\right) $-Lie ideal of $R$ such that $\tau~$commutes with $\ast$, and $a,b$ be in $R.$ $\left( i\right) $ If $a\in S_{\ast}\left( R\right) $ and $\left[ U,a\right] =0$, then $a\in Z\left( R\right) $ or $U\subset Z\left( R\right) .$ $\left( ii\right) $ If $a\in S_{\ast}\left( R\right) $ and $\left[ U,a\right] _{\sigma,\tau}\subset$ $C_{\sigma,\tau}$, then $a\in Z\left( R\right) ~$or$~U\subset Z\left( R\right) .$ $\left( iii\right) $ If $U\not \subset Z\left( R\right) $ and $U\not \subset C_{\sigma,\tau}$, then there exists a nonzero $\ast$-ideal $M$ of …
On Golden Semisymmetric Metric $F$-Connections, Aydin Gezer, Çağri Karaman
On Golden Semisymmetric Metric $F$-Connections, Aydin Gezer, Çağri Karaman
Turkish Journal of Mathematics
In this paper, we construct a golden semisymmetric metric $F$-connection on a locally decomposable golden Riemannian manifold and investigate some properties of its curvature, conharmonic curvature, Weyl projective curvature, and torsion tensors. Moreover, we define the transposed connection of this connection and study its curvature properties.
Singular Dirac Systems In The Sobolev Space, Eki̇n Uğurlu
Singular Dirac Systems In The Sobolev Space, Eki̇n Uğurlu
Turkish Journal of Mathematics
In this paper we construct Weyl's theory for the singular left-definite Dirac systems. In particular, we prove that there exists at least one solution of the system of equations that lies in the Sobolev space. Moreover, we describe the behavior of the solution belonging to the Sobolev space around the singular point.
Some Theorems For A New Type Of Multivalued Contractivemaps On Metric Space, Gonca Durmaz
Some Theorems For A New Type Of Multivalued Contractivemaps On Metric Space, Gonca Durmaz
Turkish Journal of Mathematics
In this paper, taking into account the function $\theta $, we introduce a new type of contraction for multivalued maps on metric space. This new concept includes many known contractions in the literature. We then present some fixed point results for closed and bounded set valued maps on complete metric space. Finally, we provide an example to show the significance of the investigation of this paper.
New Recurrences For Euler's Partition Function, Mircea Merca
New Recurrences For Euler's Partition Function, Mircea Merca
Turkish Journal of Mathematics
In this paper, the author invokes some consequences of the bisectional pentagonal number theorem to derive two linear recurrence relations for Euler's partition function $p(n)$. As a corollary of these results, we obtain an efficient method to compute the parity of Euler's partition function $p(n)$ that requires only the parity of $p(k)$ with $k \leq n/4$.
A New Approach To Uniqueness For Inverse Sturm-Liouville Problems On Finite Intervals, Seyfollah Mosazadeh
A New Approach To Uniqueness For Inverse Sturm-Liouville Problems On Finite Intervals, Seyfollah Mosazadeh
Turkish Journal of Mathematics
In this paper, an approach for studying inverse Sturm--Liouville problems with integrable potentials on finite intervals is presented. We find the relations between Weyl solutions and $m_{j}$-functions of Sturm--Liouville problems, and by finding the connection between these and the solutions of second-order partial differential equations for transformation kernels associated with Sturm--Liouville operators, we prove the uniqueness of the solution of inverse problems.
Corrigendum: On Density Theorems For Rings Of Krull Type With Zero Divisors, Başak Ay Saylam
Corrigendum: On Density Theorems For Rings Of Krull Type With Zero Divisors, Başak Ay Saylam
Turkish Journal of Mathematics
This corrigendum is written to correct some parts of the paper "On density theorems for rings of Krull type with zero divisors". The proofs of Proposition 2.4 and Proposition 4.3 are incorrect and the current note makes the appropriate corrections.
Evaluation Of Euler-Like Sums Via Hurwitz Zeta Values, Ayhan Di̇l, Istvan Mezo, Mehmet Cenkci̇
Evaluation Of Euler-Like Sums Via Hurwitz Zeta Values, Ayhan Di̇l, Istvan Mezo, Mehmet Cenkci̇
Turkish Journal of Mathematics
In this paper we collect two generalizations of harmonic numbers (namelygeneralized harmonic numbers and hyperharmonic numbers) under one roof.Recursion relations, closed-form evaluations, and generating functions of thisunified extension are obtained. In light of this notion we evaluate someparticular values of Euler sums in terms of odd zeta values. We alsoconsider the noninteger property and some arithmetical aspects of this unifiedextension.
Piecewise Asymptotically Almost Periodic Solution Of Neutral Volterra Integro-Differential Equations With Impulsive Effects, Zhinan Xia
Turkish Journal of Mathematics
In this paper, we investigate the existence and uniqueness ofa piecewise asymptotically almost periodic mild solution tononautonomous neutral Volterra integro-differential equations withimpulsive effects in Banach space. The working tools are based onthe Krasnoselskii's fixed point theorem and semigroup theory. Inorder to illustrate our main results, we study the piecewiseasymptotically almost periodic solution of the impulsive partialdifferential equations with Dirichlet conditions.
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 …
A Modified Genetic Algorithm For A Special Case Of The Generalized Assignment Problem, Murat Dörterler, Ömer Faruk Bay, Mehmet Ali̇ Akcayol
A Modified Genetic Algorithm For A Special Case Of The Generalized Assignment Problem, Murat Dörterler, Ömer Faruk Bay, Mehmet Ali̇ Akcayol
Turkish Journal of Electrical Engineering and Computer Sciences
Many central examinations are performed nationwide in Turkey. These examinations are held simultaneously throughout Turkey. Examinees attempt to arrive at the examination centers at the same time and they encounter problems such as traffic congestion, especially in metropolises. The state of mind that this situation puts them into negatively affects the achievement and future goals of the test takers. Our solution to minimize the negative effects of this issue is to assign the test takers to closest examination centers taking into account the capacities of examination halls nearby. This solution is a special case of the generalized assignment problem (GAP). …
Warped Product Spaces With Ricci Conditions, Sang Deok Lee, Byung Hak Kim, Jin Hyuk Choi
Warped Product Spaces With Ricci Conditions, Sang Deok Lee, Byung Hak Kim, Jin Hyuk Choi
Turkish Journal of Mathematics
In this paper, we study the Ricci soliton in the Riemannian products$M=R^n \times B$ and warped products $M=R \times _f B$ of theEuclidean space and Riemannian manifolds, and the gradient Riccisoliton in the warped products $M=S^1 \times _f B$ of 1-dimensionalcircle and Riemannian manifolds. Moreover, we introduce the concept ofthe generalized Ricci soliton and we suggest the method of constructionof the Riemannian manifold $(M, g)$ with a Ricci soliton $g$.Finally, we also study the Lorentzian warped products with the Riccisoliton.
An Efficient Ofdm-Based System With An Insufficient Cyclic Prefix Via A Novel Constellation Algorithm, Saeed Ghazi-Maghrebi
An Efficient Ofdm-Based System With An Insufficient Cyclic Prefix Via A Novel Constellation Algorithm, Saeed Ghazi-Maghrebi
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a new special triangular constellation scheme is introduced to replace the commonly used rectangular QAM constellation in orthogonal frequency division multiplexing (OFDM) modulation. We have shown that this new scheme has 3 major advantages with respect to the well-known QAM. The first advantage is its lower error probability performance, which results from better usage of the constellation space with longer minimum distances. The 2 other advantages are a lower peak to average power ratio (PAPR) and higher noise immunity. Both mathematical analysis and simulation results demonstrate that by applying standard channels in 2 cases, i.e. channels with …
Neoteric Chaff Generation Method Of Fingerprint Fuzzy Vault, Nancy Singla, Sanjeev Sofat, Manvjeet Kaur
Neoteric Chaff Generation Method Of Fingerprint Fuzzy Vault, Nancy Singla, Sanjeev Sofat, Manvjeet Kaur
Turkish Journal of Electrical Engineering and Computer Sciences
Authentication using biometrics has an edge over traditional authentication mechanisms. Fuzzy vault is an eminent biometric cryptosystem technique that aims to protect a secret using a biometric template. Authorized users can, however, access the secret by providing the valid biometric. In a fuzzy vault, noise is incorporated in the form of chaff points in order to increase the security. While implementing fuzzy vault schemes in real scenarios, the most critical but computing-intensive and time-consuming task is chaff generation. In this paper, a neoteric method for chaff generation is proposed, which is less time-consuming in generating large numbers of chaff points.
Synthesis And Cytotoxicity Of Novel Thioxo-Quinazolino[3,4-$A$]Quinazolinones, Negar Mohammadhosseini, Mina Saeedi, Shahram Moradi, Mohammad Mahdavi, Omidreza Firuzi, Alireza Foroumadi, Abbas Shafiee
Synthesis And Cytotoxicity Of Novel Thioxo-Quinazolino[3,4-$A$]Quinazolinones, Negar Mohammadhosseini, Mina Saeedi, Shahram Moradi, Mohammad Mahdavi, Omidreza Firuzi, Alireza Foroumadi, Abbas Shafiee
Turkish Journal of Chemistry
Various thioxo-quinazolino[3,4-$a$]quinazolinones were prepared and evaluated for their cytotoxicity in MOLT-4 (lymphoblastic leukemia) and MCF-7 (breast adenocarcinoma) cell lines. Synthesis of the target compounds was started from isatoic anhydride. Successive reaction of isatoic anhydride with benzylamine and 2-nitrobenzaldehyde, reduction of the nitro group, and reaction with CS$_{2}$ gave 12-benzyl-6-thioxo-6,7,11b,12-tetrahydro-13$H$-quinazolino[3,4-$a$]quinazolin-13-one. The latter compound reacted with various 2-chloro-$N$-substituted acetamides to afford the corresponding fused quinazolinone derivatives.
Synthesis And Characterization Of Magnetic Amidoximated Chitosan-G Poly(Polyacrylonitrile)/Laponite Rd Nanocomposites With Enhanced Adsorption Capacity For Cu$^{2+}$, Gholam Reza Mahdavinia, Ebrahim Shokri
Synthesis And Characterization Of Magnetic Amidoximated Chitosan-G Poly(Polyacrylonitrile)/Laponite Rd Nanocomposites With Enhanced Adsorption Capacity For Cu$^{2+}$, Gholam Reza Mahdavinia, Ebrahim Shokri
Turkish Journal of Chemistry
Magnetic amidoximated nanocomposites based on a combination of chitosan and magnetic laponite RD were prepared and examined for the removal of Cu$^{2+}$ from aqueous solutions. Magnetic laponite RD was prepared by an in situ method. In order to prepare magnetic amidoximated nanocomposites, acrylonitrile was grafted to chitosan in the presence of magnetic laponite RD. Then the nitrile pendants on magnetic chitosan-g-polyacrylonitrile/laponite RD (mChtioPANLap) were converted to amidoxime groups. We developed a polyamidoximated magnetic nanocomposite based on a mixture of chitosan/laponite RD, possessing a high adsorption capacity for Cu$^{2+}$. By introducing magnetic laponite RD the adsorption capacity of nanocomposites for Cu$^{2+}$ …
Isocoumarins And 3,4-Dihydroisocoumarins, Amazing Natural Products: A Review, Aisha Saddiqa, Osman Çakmak, Muhammad Usman
Isocoumarins And 3,4-Dihydroisocoumarins, Amazing Natural Products: A Review, Aisha Saddiqa, Osman Çakmak, Muhammad Usman
Turkish Journal of Chemistry
The isocoumarins are naturally occurring lactones that constitute an important class of natural products exhibiting an array of biological activities. A wide variety of these lactones have been isolated from natural sources and, due to their remarkable bioactivities and structural diversity, great attention has been focused on their synthesis. This review article focuses on their structural diversity, biological applications, and commonly used synthetic modes.
Impact Of Surface Modification Of Green Algal Biomass By Phosphorylation On The Removal Of Copper(Ii) Ions From Water, Zakaria Al-Qodah, Mohammad Al-Shannag, Abdulaziz Amro, Eman Assirey, Mustafa Bob, Khalid Bani-Melhem, Malek Alkasrawi
Impact Of Surface Modification Of Green Algal Biomass By Phosphorylation On The Removal Of Copper(Ii) Ions From Water, Zakaria Al-Qodah, Mohammad Al-Shannag, Abdulaziz Amro, Eman Assirey, Mustafa Bob, Khalid Bani-Melhem, Malek Alkasrawi
Turkish Journal of Chemistry
A series of batch lab-scale experiments were performed to investigate the performance of dead phosphorylated algal biomass of Spirogyra species for the bioadsorption of Cu$^{+2}$ ions from aqueous solutions. FT-IR and SEM analyses were performed to characterize the phosphorylated and raw algae. The SEM analysis indicated that the phosphorus content increases by about 5 times. The isotherm equilibrium data indicated that phosphorylation enhances the removal of Cu$^{+2}$ from water by about 20%. The experimental isotherms fit well to Langmuir models with $R^{2}$ values close to 0.99. Adsorption kinetic study was conducted to investigate the effect of initial Cu$^{+2}$ concentrations, pH, …