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Abstract

Let fL 2π be a real-valued even function with its Fourier series , and let S n(f,x) be the nth partial sum of the Fourier series, n≧1. The classical result says that if the nonnegative sequence {a n} is decreasing and , then if and only if . Later, the monotonicity condition set on {a n} is essentially generalized to MVBV (Mean Value Bounded Variation) condition. Very recently, Kórus further generalized the condition in the classical result to the so-called GM7 condition in real space. In this paper, we give a complete generalization to the complex space.

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Abstract  

The results of an investigation concerning there action between 1,2-propanediol and Co(NO3)2⋅ 6H2O, leading to a complex containing the lactate anion (L) as ligand are presented. The obtained solid homopolynuclear coordination compound[Co2(OH)2L2(H2O)2⋅0.5H2O]n, has been investigated by thermal analysis, electronic and IR spectroscopy and magnetic methods. Cobalt oxide obtained by thermal decomposition of this coordinative compound was characterized by IR and X-ray spectroscopy.

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Abstract  

Solvent extraction of microamounts of europium and cerium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B) in the presence of polyethylene glycol PEG 600 (L) has been investigated. The equilibrium data have been explained assuming that the complexes HL+, H2L2+ and ML3+ (M3+ = Eu3+, Ce3+; L = PEG 600) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined. It was found that the stability constants of the EuL3+ and CeL3+ cationic complex species (L = PEG 600) in water-saturated nitrobenzene are the same.

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Abstract  

Solvent extraction of microamounts of europium and cerium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B) in the presence of polyethylene glycol PEG 1000 (L) has been investigated. The equilibrium data have been explained assuming that the species H2L2+ and ML3+ (M3+ = Eu3+, Ce3+) are extracted into the organic phase. The values of extraction and stability constants of the complexes in nitrobenzene saturated with water have been determined. It was found that the stability constants of the cationic complex species EuL3+ and CeL3+ in water-saturated nitrobenzene are practically the same.

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The aim of the current investigation was to investigate the effect of photoperiod on thyroid activity in soft-shelled turtles ( Lissemys punctata punctata ). Thirty days exposure of short photoperiod with 2L: 22D increased relative weight, follicular epithelial height and peroxidase activity of the thyroid gland; whereas exposure of long photoperiod with 22L: 2D for 30 days showed reversed changes to those of the short photoperiod in adult female turtles. These findings indicate that short photoperiod stimulates thyroid activity and long photoperiod inhibits its activity in soft-shelled turtles. It is suggested that photoperiod exerts its action on thyroid activity presumably via gonads and/or pineal-gonadal axis in turtles.

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Abstract  

Cobalt(II), nickel(II) and copper(II) complexes of Schiff’s bases derived from 4,4′-methylenedianiline and pyridine-2-carboxaldehyde(L1), furan-2-carboxaldehyde(L2) or thiophene-2-carboxaldehyde(L3), were prepared and characterized by different analytical and spectral methods. The Schiff bases behave as neutral tetradentate ligands. The chloro-complexes of (L2) with (2:3) mole ratio have a polymeric nature. However, that of L1 and L3 with (1:1) mole ratio showed a sandwich structure. All complexes display an octahedral geometry, except complex (2) which has a tetrahedral one. O h/T d equilibrium for chloro-complexes of cobalt with ligand L1 was established in the solid state. ESR spectra of solid copper(II) complexes showed isotropic and axial type with dx 2-y 2 ground state. The thermal study showed that the complexes with different solvents of crystallization exercise different types of interaction. The observed thermochromic phenomenon for cobalt complex was explained along with its thermal behaviour.

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Journal of Thermal Analysis and Calorimetry
Authors: Rodica Olar, Mihaela Badea, Dana Marinescu, Emilia Iorgulescu, Eliza Frunza, Veronica Lazar, and Carmen Chifiriuc

Abstract  

New complexes of type [Cu(HTBG)2]Cl2 (1), [Cu(TBG)2]·3H2O (2) and [CuL]·nH2O (3) L:L1, n = 2 and (4) L:L2, n = 1 (HTBG: 2-tolylbiguanide, L1 and L2: ligands resulted from 2-tolylbiguanide, ammonia/hydrazine and formaldehyde one pot condensation) were synthesised and characterised. The features of complexes have been assigned from microanalytical, IR and UV–Vis data. Redox behaviour was established by cyclic voltammetry. The in vitro qualitative and quantitative antimicrobial activity assays showed that the complexes exhibited variable antimicrobial activity against Gram-negative and Gram-positive strains isolated from the hospital environment. The thermal analyses have evidenced the thermal intervals of stability and also the thermodynamic effects that accompany them. After water elimination, complexes have a similar thermal behaviour. Processes as water elimination, melting, chloride anion removal as well as oxidative degradation of the organic ligands were observed. The final product of decomposition was copper (II) oxide.

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The thermal properties of coordination compounds of the composition Cu(NCS)2L2 (whereL=pyridine, 2-, 3- and 4-picoline, and 2,3-, 2,4-, 2,5-, 2,6-, 3,4- and 3,5-lutidine) are dealt with. The thermal decomposition of these compounds begins with the release of the ligandL. The compounds with pyridine derivatives containing a methyl substituent at position 2 show a markedly decreased initial decomposition temperature. It was found that X-ray irradiation caused a reduction of the central atom Cu(II) in the coordination compounds under investigation. X-ray electron spectra data showed the stability of the compounds Cu(NCS)2L2 withL=picoline or lutidine having a methyl substituent at position 2 to be distinctly lower in the surface layers. From the given series, the compounds Cu(NCS)2(pyridine)2 and Cu(NCS)2(3,5-lutidine)2 exhibit an analogous course of thermal decomposition in nitrogen atmosphere up to 600°. The stoichiometries of thermal decomposition are discussed.

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Journal of Thermal Analysis and Calorimetry
Authors: R. Olar, M. Badea, D. Marinescu, E. Iorgulescu, and S. Stoleriu

Summary This paper deals with the first investigation concerning the thermal behaviour of Ni(II) complexes with ligands having biguanide moieties. The new complex [NiL(1)](ClO4)2·2.5H2O (1) with the Schiff base resulted in [2+1] condensation of N,N-dimethylbiguanide with pentane-2,4-dione (L(1)) and the complex [Ni2L(2)](ClO4)4 (2), with the Schiff base, L(2), resulted through the oxidative condensation of L(1) have been synthesized and characterised. The bonding and stereochemistry of the complexes have been characterized by IR and electronic spectra. The cyclic voltammograms show the characteristic waves for mononuclear and respectively binuclear Ni(II) complexes and indicate that both complexes exhibit catalytic effects on the CO2 electrochemical reduction. The thermal behaviour provided confirmation of the complexes composition as well as the number and the nature of water molecules and the intervals of thermal stability. The different nature of the ligands generates a different thermal behaviour for complexes.

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The aim of the present article is to give an overview of the most important approaches to translation competence. As the term ‘competence’ is used in a somewhat arbitrary way in translation studies, psychological approaches to competence are reviewed first. Then some influential translation competence models are presented and analyzed. Translation competence models are classified into three categories based on Pym (2003). The outlined translation competence models are also related to the psychological concepts of competence described at the beginning of the study. Finally, recurrent issues related to translation competence are identified and discussed briefly. These issues involve the relationship between language competence and translation competence; the existence of a separate transfer component of competence, the status of natural translation and the differences between L1→L2 and L2→L1 translation. It is concluded that none of the models of translation competence is inherently better than the others. It is always the purpose of a given piece of research or project that should determine the type of competence model to be adopted.

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