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Articles 7021 - 7050 of 10319
Full-Text Articles in Physical Sciences and Mathematics
Reaction Dynamics Of Br + Hd: Quantum Wave Packet On Three Potential Energy Surfaces, Qing Song, Wei-Long Quan, Tian-Jun Feng
Reaction Dynamics Of Br + Hd: Quantum Wave Packet On Three Potential Energy Surfaces, Qing Song, Wei-Long Quan, Tian-Jun Feng
Turkish Journal of Chemistry
The initial state-resolved reaction probabilities, reaction cross-sections, and rate constants of the reaction Br + HD are computed on 3 potential energy surfaces (denoted as e-LEPS, MB2, and MB3, respectively) by carrying out quantum time-dependent wave packet calculations. The results show that the reactivity of Br + HD on MB3 is much stronger than that on e-LEPS and somewhat weaker than that on MB2. Both of the vibrational and the rotational excitation of reagent HD enhance the reaction, which depends on the PESs and the strongest enhancement effects are on e-LEPS.
Simultaneous Determination Of Trace Sn(Ii) And Sn(Iv) Using Differential Pulse Polarography And Application, Güler Somer, Ülkü Ünal
Simultaneous Determination Of Trace Sn(Ii) And Sn(Iv) Using Differential Pulse Polarography And Application, Güler Somer, Ülkü Ünal
Turkish Journal of Chemistry
A new method was established for the simultaneous determination of Sn(II) and Sn(IV) using differential pulse polarography (DPP). Among several electrolytes, 0.1 M NaOH in the presence of 0.1 M KNO_3 was found to be the most suitable one. In this medium, Sn(II) had 2 peaks, at -0.74 and -1.17 V, which were sharp and very sensitive. Sn(IV), on the other hand, had a very small peak at -0.92 V when its concentration was higher than 4.0 \times 10^{-4} M. Thus, it was decided to determine Sn(IV) after reduction into Sn(II). In the presence of both Sn(II) and Sn(IV), Sn(II) …
Azocalixarenes.7: Synthesis And Study Of The Absorption Properties Of Novel Mono-Azo Substituted Chromogenic Calix[4]Arenes, Hasaletti̇n Deli̇göz, Özlem Özen Karakuş
Azocalixarenes.7: Synthesis And Study Of The Absorption Properties Of Novel Mono-Azo Substituted Chromogenic Calix[4]Arenes, Hasaletti̇n Deli̇göz, Özlem Özen Karakuş
Turkish Journal of Chemistry
Eight new mono-azo substituted chromogenic calix[4]arenes (1-8) were synthesized by diazo-coupling reactions in which 25,26,27-tribenzoyloxy-28-hydroxy-5,11,17-tri-(tert-butyl)calix[4]arene and diazonium salts (2-, 3-, and 4-nitroaniline; 4-phenyl azoaniline; 3- and 4-chloroaniline; or 2- and 4-methylaniline) formed the corresponding mono-azo substituted derivatives in high yields. The mono-azo substituted calix[4]arenes were characterized by UV-Vis, FT-IR, and ^1H-NMR spectroscopic techniques. Elemental analysis was also carried out. In addition, the effects of varying pH levels and solvents upon the absorption ability of azocalix[4]arenes substituted with electron-donating and electron-withdrawing groups at their o-, m-, and p- positions were studied. The results proved that the absorption maxima of the prepared …
Synthesis And Biological Activity Of 5-Substituted-2-Amino-1,3,4-Oxadiazole Derivatives, Sanjeev Kumar
Synthesis And Biological Activity Of 5-Substituted-2-Amino-1,3,4-Oxadiazole Derivatives, Sanjeev Kumar
Turkish Journal of Chemistry
Electrical energy offers numerous benefits for performing synthesis, including increased reaction rates, enhanced yields, and cleaner chemistries. 5-Substituted-2-amino-1,3,4-oxadiazoles were synthesized directly from the semicarbazone at a platinum electrode under controlled potential electrolysis in an undivided cell assembly in acetonitrile. The compounds were screened for antibacterial and antifungal activity against Staphylococcus aureus, Klebsiella pneumoniae, Pellicularia salmonicolor, and Macrophomina phaseolina.
A Study Of Behavior Of Some 5-Substituted- 4-Phenyl-1,2,4-Triazoline-3-Thiones In Sulfuric Acid Solution Using Characteristic Vector Analysis, Vesna Dimova
Turkish Journal of Chemistry
The protonation process of 1,2,4-triazoline-3-thiones (T3T) was studied in aqueous sulfuric acid using the UV method. Characteristic vector analysis (CVA) was used to reconstruct the experimentally obtained UV spectra, to overcome difficulties in calculating the protonation constants of T3T, and to separate the effect of protonation from the generalized medium effect. pK_{TH}+ values were calculated using the Hammett acidity function method, the Bunnett and Olsen method, and the excess acidity function method. The obtained values for m, \phi and m* were close to those characteristic for similar thio compounds, indicating that the protonation site in the molecule of T3T is …
Synthesis And Evaluation Of The Analgesic Activity Of Some New Isoxazolo[4,5-D]Pyridazin-4(5h)-One Derivatives, Oya Ünsal Tan, Keri̇man Özadali, Özgür Yeşi̇lyurt, Hakan Kayir, İsmai̇l Tayfun Uzbay, Ayla Balkan
Synthesis And Evaluation Of The Analgesic Activity Of Some New Isoxazolo[4,5-D]Pyridazin-4(5h)-One Derivatives, Oya Ünsal Tan, Keri̇man Özadali, Özgür Yeşi̇lyurt, Hakan Kayir, İsmai̇l Tayfun Uzbay, Ayla Balkan
Turkish Journal of Chemistry
Some isoxazolo[4,5-d]pyridazin4(5H)-one derivatives were synthesized and tested for their analgesic activity. The analgesic activities of the compounds were determined by hot-plate and acetic acid writhing tests using morphine and diclofenac as references. Compounds 4a, 4f, 4g, and 4i (25 mg/kg) showed analgesic profiles similar to that of morphine (5 mg/kg).
Synthesis And Antiinflammatory Activity Of Novel 2,5-Disubstituted Thiophene Derivatives, Sahar Badr
Synthesis And Antiinflammatory Activity Of Novel 2,5-Disubstituted Thiophene Derivatives, Sahar Badr
Turkish Journal of Chemistry
New series of 2,5-disubstituted thiophenes were synthesized. Thiosemicarbazones 1a-b were reacted with various reagents, such as diethyl-2-bromomalonate, ethyl-2-chloroacetoacetate, thioglycolic acid, 4-substituted phenacyl bromides, and acetic anhydride, to afford heterocyclic substituted thiophene derivatives 2a-b, 3a-b, 4a-b, 5a-b, 6a-b, and 7a-b, respectively. Moreover, cyclization of the key intermediate 1b with chloroacetic acid yielded thiazolidine 9, which on reaction with appropriate aromatic aldehydes afforded the corresponding arylidene derivatives 10a-f. Finally, reaction of N^\-arylidene cyanoacetohydrazide 11 with sulfur and phenylisothiocyanate yielded thiazoline derivative 12, which on treatment with triethylorthoformate and acetic anhydride afforded thiazolo[4,5-d]pyrimidinone derivative 13. Some of the newly synthesized compounds showed promising …
A Simple And Rapid Spectrophotometric Determination Of Trace Level Simple And Rapid Spectrophotometric Determination Of Trace Level Chromium Using Bis (Salicylaldehyde) Orthophenylenediamine In Nonionic Micellar Media, Rubina Soomro, Jamaluddin Ahmed, Najma Memon
A Simple And Rapid Spectrophotometric Determination Of Trace Level Simple And Rapid Spectrophotometric Determination Of Trace Level Chromium Using Bis (Salicylaldehyde) Orthophenylenediamine In Nonionic Micellar Media, Rubina Soomro, Jamaluddin Ahmed, Najma Memon
Turkish Journal of Chemistry
Bis(salicylaldehyde)orthophenylenediamine (BSOPD) has been proposed as new analytical reagent for the direct spectrophotometric determination of chromium. It reacts with chromium(VI) in slightly acidic (0.1 -- 0.3 M H_2SO_4) micellar medium to form a yellow - orange chelate with a molar ratio 2:3. The most remarkable point of this method is that the molar absorptivities of the Cr^{VI} -- BSOPD complex formed in the presence of nonionic TritonX -- 100 surfactant are almost 10 times higher than the value observed in aqueous solution. This results in enhancing the sensitivity and selectivity of the method. The reaction is instantaneous and the maximum …
Papr Reduction Using Artificial Bee Colony Algorithm In Ofdm Systems, Necmi̇ Taşpinar, Dervi̇ş Karaboğa, Mahmut Yildirim, Bahri̇ye Akay
Papr Reduction Using Artificial Bee Colony Algorithm In Ofdm Systems, Necmi̇ Taşpinar, Dervi̇ş Karaboğa, Mahmut Yildirim, Bahri̇ye Akay
Turkish Journal of Electrical Engineering and Computer Sciences
Partial transmit sequence (PTS) is an attractive scheme for peak-to-average power ratio (PAPR) reduction in orthogonal frequency division multiplexing (OFDM) systems, but its high computational complexity to find optimum phase factors is the main drawback. In this paper, we propose PTS based on an artificial bee colony (ABC) algorithm (ABC-PTS) for reducing the computational complexity of the PTS in the OFDM system. The ABC-PTS was compared to conventional PTS using a random search strategy (RS-PTS) and optimum PTS. In addition, the bit error rate (BER) performance of the ABC-PTS was shown when a high power amplifier (HPA) was used for …
The Low Temperature Resistivity Of Thermally Evaporated Antiferromagnetic Mn_{100-X} Ru_X Thin Films, Francis Kofi Ampong, Francis Boakye
The Low Temperature Resistivity Of Thermally Evaporated Antiferromagnetic Mn_{100-X} Ru_X Thin Films, Francis Kofi Ampong, Francis Boakye
Turkish Journal of Physics
Electrical resistivity measurements on thermally evaporated Mn_{100-x} Ru_x thin films (with x = 0.05 at.% Ru and x = 2.5 at.% Ru) have been carried out over the temperature range from 300 to 1.4 K. A behaviour typical of the bulk \alpha-Mn has been observed on the film with x = 0.05 at.% Ru. The Néel point of this specimen is established at 90 \pm 1 K which is typical of the bulk. This Néel point is raised to 100 \pm 1 K with x = 2.5 at.% Ru in \alpha-Mn. A relatively long range magnetic ordering was observed with …
Preparation, Morphology, And Thermomechanical Properties Of Coal Ash/Polyethylene Oxide Composites, Khalid Saeed, Muhmmad Ishaq, Muhmmad Ilyas
Preparation, Morphology, And Thermomechanical Properties Of Coal Ash/Polyethylene Oxide Composites, Khalid Saeed, Muhmmad Ishaq, Muhmmad Ilyas
Turkish Journal of Chemistry
Coal ash/polyethylene oxide (ash/PEO) composite films were prepared by the solution casting technique. Scanning electron microscopy (SEM) micrographs indicated that the ash particles were dispersed and embedded well within the polymer matrix. The size of the ash particles in the PEO matrix was less than 3 \mu m. The polarized optical microscopic (POM) analyses revealed that the pure PEO, upon crystallization, showed distinct crystalline spherulites of a considerable size. The size of the spherulites was decreased by the incorporation of ash particles into the polymer matrix, which might be due to the nucleation role of ash in ash/PEO composite, and …
Properties Of Rd-Projective And Rd-Injective Modules, Lixin Mao
Properties Of Rd-Projective And Rd-Injective Modules, Lixin Mao
Turkish Journal of Mathematics
In this paper, we first study RD-projective and RD-injective modules using, among other things, covers and envelopes. Some new characterizations for them are obtained. Then we introduce the RD-projective and RD-injective dimensions for modules and rings. The relations between the RD-homological dimensions and other homological dimensions are also investigated.
Invariant Subspace Problem For Positive L-Weakly And M-Weakly Compact Operators, Cevri̇ye Tonyali, Erdal Bayram
Invariant Subspace Problem For Positive L-Weakly And M-Weakly Compact Operators, Cevri̇ye Tonyali, Erdal Bayram
Turkish Journal of Mathematics
In this paper, we show that positive L-weakly and M-weakly compact operators on some real Banach lattices have a non-trivial closed invariant subspace. Also, we prove that any positive L-weakly (or M-weakly) compact operator T:E \rightarrow E\ has a non-trivial closed invariant subspace if there exists a Dunford-Pettis operator S:E \rightarrow E satisfying 0 \leq T \leq S, where E is Banach lattice.
Products Of Multiplication, Composition And Differentiation Between Weighted Bergman-Nevanlinna And Bloch-Type Spaces, Ajay K. Sharma
Products Of Multiplication, Composition And Differentiation Between Weighted Bergman-Nevanlinna And Bloch-Type Spaces, Ajay K. Sharma
Turkish Journal of Mathematics
Let \varphi and \psi be holomorphic maps on D such that \varphi ( D ) \subset D . Let C_{\varphi} , M_{\psi} and D be the composition, multiplication and differentiation operators, respectively. In this paper, we consider linear operators induced by products of these operators from Bergman-Nevanlinna spaces A^{\beta}_N to Bloch-type spaces. In fact, we prove that these operators map A^{\beta}_N compactly into Bloch-type spaces if and only if they map A^{\beta}_N boundedly into these spaces.
Domination Polynomials Of Cubic Graphs Of Order 10, Saeid Alikhani, Yee-Hock Peng
Domination Polynomials Of Cubic Graphs Of Order 10, Saeid Alikhani, Yee-Hock Peng
Turkish Journal of Mathematics
Let G be a simple graph of order n. The domination polynomial of G is the polynomial D(G,x)=\sum_{i=\gamma(G)}^n d(G,i) x^i, where d(G,i) is the number of dominating sets of G of size i, and \gamma(G) is the domination number of G. In this paper we study the domination polynomials of cubic graphs of order 10. As a consequence, we show that the Petersen graph is determined uniquely by its domination polynomial.
Pseudo Pq-Injective Modules, Zhanmin Zhu
Pseudo Pq-Injective Modules, Zhanmin Zhu
Turkish Journal of Mathematics
A module M_R is called Pseudo PQ-injective (or PPQ-injective for short) if every monomorphism from a principal submodule of M to M extends to an endomorphism of M. Some characterizations and properties of this class of modules are investigated, PPQ-injective modules with some additional conditions are studied, semisimple artinian rings are characterized by PPQ-injective modules.
Kinetic Spectrophotometric Determination Of Trace Copper(Ii) Ions By Their Catalytic Effect On The Reduction Of Brilliant Cresyl Blue By Ascorbic Acid, Hali̇l İbrahi̇m Ulusoy, Ramazan Gürkan, Mehmet Akçay
Kinetic Spectrophotometric Determination Of Trace Copper(Ii) Ions By Their Catalytic Effect On The Reduction Of Brilliant Cresyl Blue By Ascorbic Acid, Hali̇l İbrahi̇m Ulusoy, Ramazan Gürkan, Mehmet Akçay
Turkish Journal of Chemistry
In the present study, a novel catalytic-kinetic spectrophotometric method was developed for the determination of trace amounts of copper. It is based on the catalytic effect of Cu(II) on the reduction of brilliant cresyl blue (BCB) by ascorbic acid in pH 5.0 acetate buffer medium. The reaction was monitored spectrophotometrically by measuring the decrease in absorbance of BCB at 624 nm. The operating conditions regarding concentration of reagents, pH, time, and temperature were established and optimized in detail. The working curve was linear in the concentration range of 0.1-5.0 \mu g L^{-1}. The maximum percentage error and standard deviation for …
Multi-Dimensional Weiss Operators, Sergey Bori̇senok, Mehmet Hakan Erkut, Yaşar Polatoğlu, Rüştü Murat Demi̇rer
Multi-Dimensional Weiss Operators, Sergey Bori̇senok, Mehmet Hakan Erkut, Yaşar Polatoğlu, Rüştü Murat Demi̇rer
Turkish Journal of Mathematics
We present a solution of the Weiss operator family generalized for the case of R^d and formulate a d-dimensional analogue of the Weiss Theorem. Most importantly, the generalization of the Weiss Theorem allows us to find a subset of null class functions for a partial differential equation with the generalized Weiss operators. We illustrate the significance of our approach through several examples of both linear and non-linear partial differential equations.
Graded Multiplication Modules And The Graded Ideal \Theta_G (M), Shahabaddin Ebrahimi Atani, Reza Ebrahimi Atani
Graded Multiplication Modules And The Graded Ideal \Theta_G (M), Shahabaddin Ebrahimi Atani, Reza Ebrahimi Atani
Turkish Journal of Mathematics
Let G be a group and let R be a G-graded commutative ring. For a graded R-module M, the notion of the associated graded ideal \theta_g (M) of R is defined. It is proved that the graded ideal \theta_g (M) is important in the study of graded multiplication modules. Among various application given, the following results are proved: if M is a graded faithful multiplication module, then \theta_g (M) is an idempotent graded multiplication ideal of R such that \theta_g (\theta_g (M)) = \theta_g (M), and every graded representable multiplication R-module is finitely generated.
Generalized Derivations On Lie Ideals In Prime Rings, Öznur Gölbaşi, Emi̇ne Koç
Generalized Derivations On Lie Ideals In Prime Rings, Öznur Gölbaşi, Emi̇ne Koç
Turkish Journal of Mathematics
Let R be a prime ring with characteristic different from two, U a nonzero Lie ideal of R and f be a generalized derivation associated with d. We prove the following results: (i) If [u,f(u)] \in Z, for all u \in U, then U \subset Z. (ii) (f,d) and (g,h) be two generalized derivations of R such that f(u)v=ug(v), for all u,v \in U, then U \subset Z. (iii) f([u,v])=\pm \lbrack u,v], for all u,v\in U, then U \subset Z.
On The Stability Of Basisness In L_P(1 < P < +\Infty) Of Cosines And Sines, Ali Huseynli
On The Stability Of Basisness In L_P(1 < P < +\Infty) Of Cosines And Sines, Ali Huseynli
Turkish Journal of Mathematics
We study the basis properties in L_p(0, \pi) (1 < p < \infty) of the solution system of Sturm--Liouville equations with different types of initial conditions. We first establish some results on the stability of the basis property of cosines and sines in L_p(0, \pi) (1 < p < \infty) and then show that the solution system above forms a basis in L_p(0, \pi) if and only if certain cosine system (or sine system, depending on type of initial conditions) forms a basis in L_p(0, \pi).
Order Continuous Operators On Cd_0(K,E) And Cd_W(K,E)-Spaces, Faruk Polat
Order Continuous Operators On Cd_0(K,E) And Cd_W(K,E)-Spaces, Faruk Polat
Turkish Journal of Mathematics
In [2], Alpay and Ercan characterized order continuous duals of spaces CD_0(K, E) and CD_w(K, E) where K is a compact Hausdorff space without isolated points and E is a Banach lattice. In this note, we generalize their results to an arbitrary Dedekind complete Banach lattice F, that is to say, we characterize order continuous operators on these spaces taking values in an arbitrary Dedekind complete Banach lattice F.
Slant Lightlike Submanifolds Of Indefinite Kenmotsu Manifolds, Ram Gupta, Sharfuddin Ahamad
Slant Lightlike Submanifolds Of Indefinite Kenmotsu Manifolds, Ram Gupta, Sharfuddin Ahamad
Turkish Journal of Mathematics
In this paper, we introduce the notion of a slant lightlike submanifold of an indefinite Kenmotsu manifold. We provide a non-trivial example and obtain necessary and sufficient conditions for the existence of a slant lightlike submanifold. Also, we give an example of a minimal slant lightlike submanifold of R_2^{9} and prove some characterization theorems.
Relative Nullity Foliations And Lightlike Hypersurfaces In Indefinite Kenmotsu Manifolds, Fortune Massamba
Relative Nullity Foliations And Lightlike Hypersurfaces In Indefinite Kenmotsu Manifolds, Fortune Massamba
Turkish Journal of Mathematics
This paper deals with the relative nullity distributions of lightlike hypersurfaces of indefinite Kenmotsu space forms, tangent to the structure vector field. Theorems on parallel vector fields are obtained. We give characterization theorems for the relative nullity distributions as well as for Einstein, totally contact umbilical and flat lightlike hypersurfaces. We show that, under a certain condition, Einstein lightlike hypersurfaces in indefinite Kenmotsu space forms have parallel screen distributions. We prove that on a parallel (or totally umbilical) lightlike hypersurface, the relative nullity space coincides with the tangent vector space.
Jackknife And Bootstrap With Cycling Blocks For The Estimation Of Fractional Parameter In Arfima Model, Lorenc Ekonomi, Argjir Butka
Jackknife And Bootstrap With Cycling Blocks For The Estimation Of Fractional Parameter In Arfima Model, Lorenc Ekonomi, Argjir Butka
Turkish Journal of Mathematics
One of most important problems concerning the ARFIMA time series model is the estimation of fractional parameter d. Various methods have been used to solve this problem, such as the log-periodogram regression of a process. In this article we propose two jackknife and bootstrap methods, which aid in the estimation of fractional parameter d. These methods involve non-overlapping blocks and moving blocks with random starting point and length. We have conducted several simulations and the results show that the estimations obtained are very close to the real parameter value.
On Generalized Witt Algebras In One Variable, Ki Bong Nam, Jonathan Pakianathan
On Generalized Witt Algebras In One Variable, Ki Bong Nam, Jonathan Pakianathan
Turkish Journal of Mathematics
We study a class of infinite dimensional Lie algebras called generalized Witt algebras (in one variable). These include the classical Witt algebra and the centerless Virasoro algebra as important examples. We show that any such generalized Witt algebra is a semisimple, indecomposable Lie algebra which does not contain any abelian Lie subalgebras of dimension greater than one. We develop an invariant of these generalized Witt algebras called the spectrum, and use it to show that there exist infinite families of nonisomorphic, simple, generalized Witt algebras and infinite families of nonisomorphic, nonsimple, generalized Witt algebras. We develop a machinery that can …
B. Y. Chen Inequalities For Submanifolds Of A Riemannian Manifold Of Quasi-Constant Curvature, Ci̇han Özgür
B. Y. Chen Inequalities For Submanifolds Of A Riemannian Manifold Of Quasi-Constant Curvature, Ci̇han Özgür
Turkish Journal of Mathematics
In this paper, we prove B. Y. Chen inequalities for submanifolds of a Riemannian manifold of quasi-constant curvature, i.e., relations between the mean curvature, scalar and sectional curvatures, Ricci curvatures and the sectional curvature of the ambient space. The equality cases are considered.
Analysis Of A Differential Equation Model Of Hiv Infection Of Cd4^+ T-Cells With Saturated Reverse Function, Xiangyun Shi, Gang Li, Xueyong Zhou, Xinyu Song
Analysis Of A Differential Equation Model Of Hiv Infection Of Cd4^+ T-Cells With Saturated Reverse Function, Xiangyun Shi, Gang Li, Xueyong Zhou, Xinyu Song
Turkish Journal of Mathematics
In this paper, an ordinary differential equation model of HIV infection of CD4^+ T-cells with saturated reverse function is studied. We prove that if the basic reproduction number R_0
Synthesis And Spectrophotometric Determination Of Acidity Constants Of 2,3,4,6'-Tetrahydroxy-3'-Sulfoazobenzene And Their Use In Determination Of Aluminum, Tufan Güray, Cemi̇l Öğreti̇r, Tevfi̇k Gedi̇kbey, Abu Ali̇ Hüseyi̇nli̇
Synthesis And Spectrophotometric Determination Of Acidity Constants Of 2,3,4,6'-Tetrahydroxy-3'-Sulfoazobenzene And Their Use In Determination Of Aluminum, Tufan Güray, Cemi̇l Öğreti̇r, Tevfi̇k Gedi̇kbey, Abu Ali̇ Hüseyi̇nli̇
Turkish Journal of Chemistry
A novel azo derivative, 2,3,4,6'-tetrahydroxy-3'-sulfoazobenzene (THSA), was synthesized by using pyrogallol. The acid dissociation constants, or K_a values, of THSA were determined by the UV-visible spectroscopic technique. The protonation and deprotonation behaviors of the title molecule were studied from the super basic to the super acid region (i.e. 10 N NaOH to 98% H_2SO_4), including the pH region. A selective and sensitive UV-visible spectrophotometric method was devised for determination of aluminum by using this ligand. The developed method was successfully applied to an alunite mineral and to pharmaceutical preparations for the determination of aluminum.
Determination Of Stability Constants Of 5-(2-Hydroxybenzylidene)-2-Thioxodihydropyrimidine-4,6(1h,5h)-Dione With Copper(Ii) And Mercury(Ii) Ions, Morteza Bahram, Nader Noroozi Pesyan, Abdolhossein Naseri, Masomeh Tasbihforosh
Determination Of Stability Constants Of 5-(2-Hydroxybenzylidene)-2-Thioxodihydropyrimidine-4,6(1h,5h)-Dione With Copper(Ii) And Mercury(Ii) Ions, Morteza Bahram, Nader Noroozi Pesyan, Abdolhossein Naseri, Masomeh Tasbihforosh
Turkish Journal of Chemistry
In this work, a hard model chemometric method was used to determine the stability constants of copper(II) and mercury(II) complexes with the newly synthesized ligand 5-(2-hydroxybenzylidene)- 2-thioxodihydropyrimidine-4,6(1H,5H)-dione in acetonitrile by UV-Vis spectrophotometry. The ligand forms stable complexes with both metal cations. The protonation constants of the ligand were also measured in an ethanol-water (1:1) mixture.