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Articles 6991 - 7020 of 10319
Full-Text Articles in Physical Sciences and Mathematics
A Stationary, Variable Dof Flight Control System For An Unmanned Quadrocopter, Vasfi̇ Emre Ömürlü, Ahmet Kirli, Utku Büyükşahi̇n, Şeref Naci̇ Engi̇n, Sedat Kurtoğlu
A Stationary, Variable Dof Flight Control System For An Unmanned Quadrocopter, Vasfi̇ Emre Ömürlü, Ahmet Kirli, Utku Büyükşahi̇n, Şeref Naci̇ Engi̇n, Sedat Kurtoğlu
Turkish Journal of Electrical Engineering and Computer Sciences
Unmanned air vehicles (UAV) and especially quadrocopters have drawn great attention in recent years because of their maneuverability and nonlinear control problem. Most of the related research concentrate on control; yet, design and communication are also some sub-topics. In this paper, a stationary, four rotor air vehicle with limited/controlled degree of freedom is constructed so that various control algorithms and their changing effects with varying vehicle dynamics can be studied on the ground for safety purposes. Ascending/descending, pitch/yaw/roll motions can be limited by setting the vehicle's degree of freedom mechanically, resulting better net observability of the control algorithms on the …
A Luenberger-Sliding Mode Observer With Rotor Time Constant Parameter Estimation In Induction Motor Drives, Mustafa Gürkan Aydeni̇z, İbrahi̇m Şenol
A Luenberger-Sliding Mode Observer With Rotor Time Constant Parameter Estimation In Induction Motor Drives, Mustafa Gürkan Aydeni̇z, İbrahi̇m Şenol
Turkish Journal of Electrical Engineering and Computer Sciences
The performance and efficiency of an induction motor drive system can be enhanced by online estimation of critical parameters such as rotor time constant. A novel Luenberger-sliding mode observer with a parameter adaptation algorithm is proposed in this paper to compensate for the parameter variation effects. The observer is comparably simple and robust relative to the previously developed observers, and yet suitable for online implementation. Simulation studies for the proposed method were conducted in a MATLAB environment. Observer constants and the control parameters were tuned during the simulation studies and used during the experimental study stage. Experimental verification of the …
Investigation Of Luhn's Claim On Information Retrieval, İlker Kocabaş, Beki̇r Taner Di̇nçer, Bahar Karaoğlan
Investigation Of Luhn's Claim On Information Retrieval, İlker Kocabaş, Beki̇r Taner Di̇nçer, Bahar Karaoğlan
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, we show how Luhn's claim about the degree of importance of a word in a document can be related to information retrieval. His basic idea is transformed into z-scores as the weights of terms for the purpose of modeling term frequency (tf) within documents. The Luhn-based models represented in this paper are considered as the TF component of proposed TF \times IDF weighing schemes. Moreover, the final term weighting functions appropriate for the TF \times IDF weighting scheme are applied to TREC-6, -7, and -8 databases. The experimental results show relevance to Luhn's claim by having high …
On The Uniqueness Of Strongly Flat Covers Of Cyclic Acts, Majid Ershad, Roghaieh Khosravi
On The Uniqueness Of Strongly Flat Covers Of Cyclic Acts, Majid Ershad, Roghaieh Khosravi
Turkish Journal of Mathematics
In [1], strongly flat covers of cyclic acts are discussed and it is asked if strongly flat covers are unique. From this point of view, in this paper we give numerous classes of monoids over which strongly flat covers of cyclic acts are unique.
On Almost Complex Structures In The Cotangent Bundle, Ari̇f Sali̇mov, Aydin Gezer, Seher Aslanci
On Almost Complex Structures In The Cotangent Bundle, Ari̇f Sali̇mov, Aydin Gezer, Seher Aslanci
Turkish Journal of Mathematics
E. M. Patterson and K. Yano studied vertical and complete lifts of tensor fields and connections from a manifold M_n to its cotangent bundle T^{\ast} (M_n). Afterwards, K. Yano studied the behavior on the cross-section of the lifts of tensor fields and connections on a manifold M_n to T^{\ast} (M_n) and proved that when \varphi defines an integrable almost complex structure on M_n, its complete lift ^C \varphi is a complex structure. The main result of the present paper is the following theorem: Let \varphi be an almost complex structure on a Riemannian manifold M_n. Then the complete lift ^C …
Gpq Modules And Generalized Armendariz Modules, Liang Zhao, Xiaosheng Zhu
Gpq Modules And Generalized Armendariz Modules, Liang Zhao, Xiaosheng Zhu
Turkish Journal of Mathematics
Let M_R be a right R-module. We introduce the concept of right generalized p.q.-Baer modules (or simply, right GPQ modules) to extend the notion of right p.q.-Baer modules. We study on the relationship between the GPQ property of a module M_R and various quasi-Armendariz properties. We prove that every right GPQ module is a quasi-Armendariz module. As a sequence, we obtain a general form of some known results considering the p.q.Baer property of a ring, some known results are extended. Moreover, we prove that for the formal triangular ring R constructed from a pair of rings S, T and a …
The Cyclicity Of The Period Annulus Of A Quadratic Reversible System With One Center Of Genus One, Linping Peng, Yannan Sun
The Cyclicity Of The Period Annulus Of A Quadratic Reversible System With One Center Of Genus One, Linping Peng, Yannan Sun
Turkish Journal of Mathematics
This paper is concerned with a quadratic reversible and non-Hamiltonian system with one center of genus one. By using the properties of related elliptic integrals and the geometry of some planar curves defined by them, we prove that the cyclicity of the period annulus of the considered system under small quadratic perturbations is two. This verifies Gautier's conjecture about the cyclicity of the related period annulus.
Cyclic Codes Over {Z_2+Uz_2+U^2z_2+\Ldots+U^{K-1}Z_2}, Mohammed Al Ashker, Mohammed Hamoudeh
Cyclic Codes Over {Z_2+Uz_2+U^2z_2+\Ldots+U^{K-1}Z_2}, Mohammed Al Ashker, Mohammed Hamoudeh
Turkish Journal of Mathematics
In this paper, we study the structure of cyclic codes of an arbitrary length n over the ring Z_2+uZ_2+u^2Z_2+\ldots+u^{k-1}Z_2, where u^k=0. Also we study the rank for these codes, and we find their minimal spanning sets. This study is a generalization and extension of the work in reference [1].
Some Products Involving The Fourth Greek Letter Family Element \Tilde{\Delta}_S In The Adams Spectral Sequence, Xiu-Gui Liu, He Wang
Some Products Involving The Fourth Greek Letter Family Element \Tilde{\Delta}_S In The Adams Spectral Sequence, Xiu-Gui Liu, He Wang
Turkish Journal of Mathematics
Let p be an odd prime and A be the mod p Steenrod algebra. For computing the stable homotopy groups of spheres with the classical Adams spectral sequence, we must compute the E_2-term of the Adams spectral sequence, Ext_A^{\ast,\ast} (Z_p,Z_p). In this paper we prove that in the cohomology of A, the product k_0 h_n \tilde \delta _{s + 4} \in Ext_A^{s + 7, t(s,n) + s} (Z_p, Z_p), is nontrivial for n \geq 5, and trivial for n=3, 4, where \tilde\delta_{s + 4} is actually \tilde\alpha_{s + 4}^{(4)} described by Wang and Zheng, p \geq 11, 0 \leq s < p - 4 and t(s,n)=2(p-1)[(s + 2) + (s + 4)p + (s + 3)p^2 + (s + 4)p^3 + p^n].
A Quantum Theory Of The Scattering Of Soft X-Ray From Compton Effect Caused Electron Standing Wave In The Materials, Biswajit Mallick
A Quantum Theory Of The Scattering Of Soft X-Ray From Compton Effect Caused Electron Standing Wave In The Materials, Biswajit Mallick
Turkish Journal of Physics
In the present investigation, low-energy x-rays (
Strong Optical Injection Locked Semiconductor Laser For High Bit Rate Chaotic Optical Communications, Muzahim Ibrahim Azawe, Ragaad Habib Saied
Strong Optical Injection Locked Semiconductor Laser For High Bit Rate Chaotic Optical Communications, Muzahim Ibrahim Azawe, Ragaad Habib Saied
Turkish Journal of Physics
We present in this article how strong optical injection can produce chaotic dynamics in the output of the semiconductor laser that is preferable for perfect encrypted optical communication networks. Significant increase in the relaxation resonance frequency was found implying higher degree of enhancement in modulation bandwidth. Numerical investigations under the condition of strong optical injection locking of the slave laser shows that instabilities in the photon number was observed and had settled down after a time of in the order of carrier lifetime. The model presented can be used to extract the characteristic parameters of the injection locking for detuning …
Effect Of Cdcl_2/Annealing On The Crystalline Transformation Of Cdte Thin Films Grown By Evaporation At A Low Substrate Temperature, İsmai̇l Polat, Sali̇h Yilmaz, Emi̇n Bacaksiz, Mustafa Altunbaş, Murat Tomaki̇n
Effect Of Cdcl_2/Annealing On The Crystalline Transformation Of Cdte Thin Films Grown By Evaporation At A Low Substrate Temperature, İsmai̇l Polat, Sali̇h Yilmaz, Emi̇n Bacaksiz, Mustafa Altunbaş, Murat Tomaki̇n
Turkish Journal of Physics
The structural and optical properties of CdTe thin films prepared at a low substrate temperature were investigated before and after the CdCl_2/annealing. The crystal structure of CdTe film was cubic with a strong (111) preferential orientation. Annealing at 400 °C without CdCl_2 treatment results in a decrease in the (111) peak intensity while the intensities of the (220), (311) and (331) peaks appeared, indicating that the texture is significantly changed. However, after the CdCl_2/annealing, the film exhibited a hexagonal phase as a dominant structure. The scanning electron microscopy patterns showed that the as-deposited and annealed samples had almost the same …
Sequence Alignment From The Perspective Of Stochastic Optimization: A Survey, İhsan Ömür Bucak, Volkan Uslan
Sequence Alignment From The Perspective Of Stochastic Optimization: A Survey, İhsan Ömür Bucak, Volkan Uslan
Turkish Journal of Electrical Engineering and Computer Sciences
DNA and protein are the fundamental biological sequences. DNA is a fundamental molecule that plays a vital role in the processes of life. Proteins synthesized by DNA in a cell are the building blocks of every living organism. There is a variety of reasons behind the alignment of biological sequences. Biological sequence alignment helps to discover functional and structural similarity of sequences. Biologists work with these aligned sequences to construct phylogenetic trees, characterize protein families, and predict protein structure. Sequence alignment is an extremely promising field of research that is characterized by very high computational complexity. Stochastic optimization is needed …
Growth Rate Biometric Quantification By X-Ray Microtomography On Larger Benthic Foraminifera: Three-Dimensional Measurements Push Nummulitids Into The Fourth Dimension, Antonino Briguglio, Brian Metscher, Johann Hohenegger
Growth Rate Biometric Quantification By X-Ray Microtomography On Larger Benthic Foraminifera: Three-Dimensional Measurements Push Nummulitids Into The Fourth Dimension, Antonino Briguglio, Brian Metscher, Johann Hohenegger
Turkish Journal of Earth Sciences
This work demonstrates the potential of three-dimensional biometric quantification using microtomography on larger benthic foraminifera. We compare traditional linear and area measures used for calculating three-dimensional characters with actual 3D measurements made from volume images obtained using X-ray microtomography (microCT). Two specimens of recent larger benthic foraminifera, i.e., Palaeonummulites venosus and Operculina ammonoides, were imaged with a high-resolution microCT scanner. This method enables three-dimensional imaging and calculation of measurements like 3D distances, surfaces and volumes. The quantitative high-resolution images enabled the extraction of the lumina from the proloculus to the last complete scanned chamber and of the canal system spreading …
Estimating Global Solar Radiation From Common Meteorological Data In Aranjuez, Spain, Javier Almorox
Estimating Global Solar Radiation From Common Meteorological Data In Aranjuez, Spain, Javier Almorox
Turkish Journal of Physics
This study aimed to calibrate existing models and develop a new model for estimating global solar radiation data using commonly and available measured meteorological records such as precipitation or temperature. Fifteen empirical global radiation models based on meteorological variables were generated and validated using daily data in 2003-2008 at the Aranjuez station (Community of Madrid, Spain). Validation criteria included coefficient of determination, root mean square error, mean bias error, mean absolute bias error, mean percentage error, and mean absolute percentage error. The best result was derived from the model proposed, which uses extraterrestrial solar radiation, saturation vapor pressures, transformed rainfall …
Delta Excitation Calculation Studies In The Ground State Of The Compressed Finite Heavy Doubly-Magic Nucleus ^{100}Sn, Mohammed Hassen Eid Abu-Sei'leek
Delta Excitation Calculation Studies In The Ground State Of The Compressed Finite Heavy Doubly-Magic Nucleus ^{100}Sn, Mohammed Hassen Eid Abu-Sei'leek
Turkish Journal of Physics
The energies and matter densities of finite nuclei under radial compression are investigated by using a constrained Hartree-Fock method with the \Delta degree of freedom included. The results are presented for the doubly-magic nucleus ^{100}Sn in an effective baryon-baryon interaction. It is found that as the nucleus is compressed to about three time of the ordinary nuclear density, the \Delta component is sharply increased to about 17% of all baryons in the system. This result is consistent with the values extracted from relativistic heavy-ion collisions. The single particle energy levels calculated and their behaviors under compression examined too. A good …
Molecular Interaction Studies In Binary Mixtures Containing Aniline, Toluene And N-Butanol, Palaniappan Lakshmanan, Mahendran Govindasamy
Molecular Interaction Studies In Binary Mixtures Containing Aniline, Toluene And N-Butanol, Palaniappan Lakshmanan, Mahendran Govindasamy
Turkish Journal of Physics
Ultrasonic velocity and density values have been measured at 303 K in binary mixtures containing aniline, toluene and n-butanol; and the thermodynamical approach is applied to evaluate the mixtures' molar volume, adiabatic compressibility, intermolecular free length and excess values. The observed results are interpreted in terms of molecular interaction between the components of the mixtures. Observed excess values and their fittings of R-K type equations lend further support to the observation made in the binary system.
Existence Theory For Positive Solutions Of P-Laplacian Multi-Point Bvps On Time Scales, You-Hui Su
Existence Theory For Positive Solutions Of P-Laplacian Multi-Point Bvps On Time Scales, You-Hui Su
Turkish Journal of Mathematics
This paper is concerned with the one-dimensional p-Laplacian multi-point boundary value problem on time scales T: (\varphi_p(u^{\Delta}))^{\nabla} + h(t)f(u) = 0, t \in [0,T]_T, subject to multi-point boundary conditions u(0) - B_0(\sum_{i=1}^{m-2}a_i u^{\Delta}(\xi_i)) = 0, u^{\Delta}(T) = 0, or u^{\Delta}(0) = 0, u(T) + B_1(\sum_{i=1}^{m-2}b_iu^{\Delta}(\xi'_i)) = 0, where \varphi_p(u) is p-Laplacian operator, i.e., \varphi_p(u = u ^{p-2}u, p>1, \xi_i,\xi'_i\in [0,T]_T, m \geq 3 and satisfy 0 \leq \xi_1 < \xi_2 < ... < \xi_{m-2} < \rho(T), \sigma(0) < \xi'_1 < \xi'_2 < ... < \xi'_{m-2} \leq T, a_i, b_i\in [0,\infty) (i=1,2,..., m-2). Some new sufficient conditions are obtained for the existence of at least one positive solution by using Krasnosel'skii's fixed-point theorem and new sufficient conditions are obtained for the existence of twin, triple or arbitrary odd positive solutions by using generalized Avery and Henderson fixed-point theorem and Avery-Peterson fixed-point theorem. Our results include and extend some known results. As applications, two examples are given to illustrate the main results and their differences. These results are new even for the special cases of continuous and discrete equations, as well as in the general time scale setting.
Universal Inequalities And Bounds For Weighted Eigenvalues Of The Schrödinger Operator On The Heisenberg Group, Hejun Sun
Turkish Journal of Mathematics
For a bounded domain \Omega in the Heisenberg group H^n, we investigate the Dirichlet weighted eigenvalue problem of the Schrödinger operator - \Delta_{H^n} +V, where \Delta_{H^n} is the Kohn Laplacian and V is a nonnegative potential. We establish a Yang-type inequality for eigenvalues of this problem. It contains the sharpest result for \Delta_{H^n} in [17] of Soufi, Harrel II and Ilias. Some estimates for upper bounds of higher order eigenvalues and the gaps of any two consecutive eigenvalues are also derived. Our results are related to some previous results for the Laplacian \Delta and the Schrödinger operator -\Delta+V on a …
Some Properties Of Associate And Presimplifiable Rings, Manal Ghanem
Some Properties Of Associate And Presimplifiable Rings, Manal Ghanem
Turkish Journal of Mathematics
In this paper we study some properties of associate and presimplifiable rings. We give a characterization of the associate (resp., domainlike) pullback P of R_1 \rightarrow{R_3} \leftarrow{R_2}, where R_1 and R_2 are two presimplifiable (resp., domainlike) rings. We prove that R is presimplifiable ring if and only if the factor ring R/{nil(R)} is presimplifiable and the ideal nil(R) is presimplifiable. Then we investigate the associate and presimplifiable property of the dual rings {R[x]/\langle{x^2}\rangle} and its modules through the base ring R and its modules.
Probabilities For Absolute Irreducibility Of Multivariate Polynomials By The Polytope Method, Fati̇h Koyuncu, Ferruh Özbudak
Probabilities For Absolute Irreducibility Of Multivariate Polynomials By The Polytope Method, Fati̇h Koyuncu, Ferruh Özbudak
Turkish Journal of Mathematics
Motivated by the Dubickas's result in [1], which computes the probability of the irreducible polynomials by Eisenstein's criterion for some families of polynomials in Z[x], we calculate the probabilities which represent the ratio of absolutely irreducible multivariate polynomials by the polytope method in some families of polynomials over arbitrary fields.
Module Classes And The Lifting Property, Muhammet Tamer Koşan
Module Classes And The Lifting Property, Muhammet Tamer Koşan
Turkish Journal of Mathematics
Let R be a ring. A collection of R-modules containing the zero module and closed under isomorphisms will be denoted by X. An R-module M is said to be X-lifting if for every X-submodule N of M there exists A \leq N such that M=A \oplus B and N \cap B is small in B [11]. In the present paper, we consider the question: Can we characterize X-lifting modules via objects of the class X?
Top Generalized Local Cohomology Modules, Amir Mafi
Top Generalized Local Cohomology Modules, Amir Mafi
Turkish Journal of Mathematics
Let (R,m) be a commutative Noetherian local ring and M, N two non-zero finitely generated R-modules with d(M)=n
Some Results On G-Frames In Hilbert Spaces, Abdolaziz Abdollahi, Elham Rahimi
Some Results On G-Frames In Hilbert Spaces, Abdolaziz Abdollahi, Elham Rahimi
Turkish Journal of Mathematics
In this paper we show that every g-frame for a Hilbert space H can be represented as a linear combination of two g-orthonormal bases if and only if it is a g-Riesz basis. We also show that every g-frame can be written as a sum of two tight g-frames with g-frame bounds one or a sum of a g-orthonormal basis and a g-Riesz basis for H. We further give necessary and sufficient conditions on g-Bessel sequences {\Lambda_i \in L (H,H_i) : i \in J} and {\Gamma_i \in L(H,H_i): i \in J} and operators L_1, L_2 on H so that {\Lambda_iL_1+\Gamma_iL_2: …
Hall Effect On Mhd Forced Convection From An Infinite Porous Plate With Dissipative Heat In A Rotating System, Nazibuddin Ahmed, Jiwan Krishna Goswami
Hall Effect On Mhd Forced Convection From An Infinite Porous Plate With Dissipative Heat In A Rotating System, Nazibuddin Ahmed, Jiwan Krishna Goswami
Turkish Journal of Physics
An attempt has been made to study the Hall effect on MHD forced convection from an infinite horizontal porous plate with dissipative heat in a rotating system with uniform free stream when the temperature at the plate varies periodically with time. The entire system rotates with a constant angular velocity about the normal to the plate. A uniform magnetic field is assumed to be applied along the normal to the plate directed into the fluid region. The governing equations are solved analytically. The expressions for the velocity and temperature field are obtained in non-dimensional form. The skin friction due to …
Application Of Active-Osl Approximation To Some Experimental Optical Stimulated Luminescence Decay, Ayşe Güneş Tanir, Mustafa Hi̇cabi̇ Bölükdemi̇r
Application Of Active-Osl Approximation To Some Experimental Optical Stimulated Luminescence Decay, Ayşe Güneş Tanir, Mustafa Hi̇cabi̇ Bölükdemi̇r
Turkish Journal of Physics
In this work, Active-OSL Approximation (AOSLA) suggested by our previous study was applied to experimental optical stimulated luminescence decay from some sediment samples. The explanation of the AOSLA was based on the radioactive decay law of successive disintegration. It allows obtaining the peak forms of luminescence mechanism. This work shows that detrapping constants that have great importance in dating and dosimeters studies can be rapidly and clearly found using the AOSLA. Also, it can be concluded that the OSL is a process similar to the radioactive decay law of successive disintegration.
Reaction Of Cycloheptatriene Derivatives With 1,3-Diketones In The Presence Of Mn(Oac)_3, Mahi̇r Burak Südemen, Mustafa Zengi̇n, Hayri̇ye Genç, Meti̇n Balci
Reaction Of Cycloheptatriene Derivatives With 1,3-Diketones In The Presence Of Mn(Oac)_3, Mahi̇r Burak Südemen, Mustafa Zengi̇n, Hayri̇ye Genç, Meti̇n Balci
Turkish Journal of Chemistry
The reactions of some 1,3-dicarbonyl compounds with cycloheptatriene derivatives in the presence of Mn(OAc)_3 were examined. Cycloheptatriene forms mainly [2+3] and [6+3] dihydrofuran addition products derived from cycloheptatriene. However, the reaction of acetylacetone with cycloheptatriene substituted with an electron withdrawing group exclusively gave products derived from the norcaradiene structure. The formation mechanism of the products as well as the role of the substituent attached to cycloheptatriene is discussed.
Synthesis Of Some 2,3,6,8-Tetraarylimidazo[1,2-A]Pyrazine Derivatives By Using Either Reflux Or Microwave Irradiation Method, And Investigation Their Anticancer Activities, İsmai̇l Kayaği̇l, Şeref Demi̇rayak
Synthesis Of Some 2,3,6,8-Tetraarylimidazo[1,2-A]Pyrazine Derivatives By Using Either Reflux Or Microwave Irradiation Method, And Investigation Their Anticancer Activities, İsmai̇l Kayaği̇l, Şeref Demi̇rayak
Turkish Journal of Chemistry
In this study, some 2,3,6,8-tetraarylimidazo[1,2-a]pyrazine derivatives were synthesized by reacting 1-(2-aryl-2-oxoethyl)-2-aryloyl-4,5-diarylimidazoles from 2-aryloyl-4,5-diarylimidazole and 2-bromoacetophenone derivatives with ammonium acetate in acetic acid by using the method that was previously developed and repeatedly tested in our studies. Structural elucidation of the compounds was performed by IR, ^1H-NMR, and MASS spectroscopic data and elemental analysis results. Anticancer activities of selected compounds were evaluated and the noticeable activity values were reported.
Effect Of Cmc And Hpc Mixture On The Photocatalytic Activity Of Nd-Tio_2/Sio_2 Film Under Visible Light Irradiation, Parviz Aberoomand, Shahram Moradi, Susan Samadi, Mohammad Saber Tehrani, Mohammad Hadi Givianrad
Effect Of Cmc And Hpc Mixture On The Photocatalytic Activity Of Nd-Tio_2/Sio_2 Film Under Visible Light Irradiation, Parviz Aberoomand, Shahram Moradi, Susan Samadi, Mohammad Saber Tehrani, Mohammad Hadi Givianrad
Turkish Journal of Chemistry
Neodymium-titania/silica films were prepared by the sol-gel method with the addition of various amounts of hydroxy propyl cellulose (HPC) and 5.09 \times 10^{-5} g g^{-1}_{solution} of carboxy methyl cellulose (CMC) in saturated conditions. The porous Nd-TiO_2/SiO_2 was obtained after heat treatment for 2 h at 500 °C, with the surface area up to 276 m^2 g^{-1}, which was measured using the Brunauer, Emmett, and Teller (BET) method. Scanning electron microscopy (SEM) showed that the particle size of Nd-TiO_2/SiO_2 decreased and the microstructure of the film became loose in suitable conditions with the addition of CMC to HPC. Subsequently, the photocatalytic …
Synthesis And Characterisation Of Tris(2,4-Dinitrophenoxo)Monooxovanadium(V) And Its Complex Salts, Neeraj Sharma, Reena Sharma, Meena Kumari, Subhash Chaudhry
Synthesis And Characterisation Of Tris(2,4-Dinitrophenoxo)Monooxovanadium(V) And Its Complex Salts, Neeraj Sharma, Reena Sharma, Meena Kumari, Subhash Chaudhry
Turkish Journal of Chemistry
The monooxovanadium(V) complex of composition [VO(OC_6H_3(NO_2)_2-2,4)_3] (I) was synthesized by the reaction of VOCl_3 with Me_3SiOC_6H_3(NO_2)_2-2,4 in toluene and characterised by elemental analyses, molar conductance, and IR, ^1H- and ^{13}C-NMR, and mass spectral studies. The reactions of (I) with alkali metal 2,4-dinitrophenoxides [MOC_6H_3(NO_2)_2-2,4] (M = Li, Na, K) yield complex salts of composition M[VO(OC_6H_3(NO_2)_2-2,4]_4 authenticated by physicochemical and IR spectral studies. Thermal behaviour of complexes was studied by TG and DTA techniques. The molecular modelling calculations of the parent complex and its complex salts were performed to visualise the probable geometry around vanadium metal, which, coupled with spectroscopic evidence, suggests …