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141.
S. Rehman M. Arshad K. Masud R. Afzal U. Salma 《Journal of Thermal Analysis and Calorimetry》2010,102(2):715-722
A series of octahedral complexes, [M(EDDA)(H2O)2] · H2O (where, M+2 = Co(II), Cu(II), Ni(II) and Zn(II); EDDA, ethylenediamine-N,N′-diacetate), was prepared and studied by means of thermogravimetry (TG) and differential thermal analysis (DTA). Their compositions
were investigated by elemental analysis in order to ensure their purity and structural elucidation was based on spectral and
magnetic properties. Thermal decomposition of these distorted octahedral complexes, [Ni(EDDA)(H2O)2], [Co(EDDA)(H2O)2] · H2O, [Cu(EDDA)(H2O)2] · H2O and [Zn(EDDA)(H2O)2] · H2O came of in one, two, three and four steps, respectively, upon heating to 800 °C, with the loss of organic and inorganic
fragments. Ligand decomposed in three steps. The thermal degradation of all the complexes in static air atmosphere started
at temperatures lower than those observed for the free ligand degradation (Ni-complex being the only exception). The composition
of intermediates formed during degradation was confirmed by microanalysis and IR spectroscopy. The residues corresponded to
metal oxide except for Ni(II) and Zn(II) complexes. It was found that thermal stability of the complexes increased in the
following sequence:
\textCu(II) ~ \textCo(II) < \textZn(II) < \textNi(II) {\text{Cu(II)}} \sim {\text{Co(II)}} < {\text{Zn(II)}} < {\text{Ni(II)}} 相似文献
142.
Let τ be a locally convex topology on the countable dimensional polynomial ${\mathbb{R}}$ -algebra ${\mathbb{R} [\underline{X}] := \mathbb{R} [X_1, \ldots, X_{n}]}$ . Let K be a closed subset of ${\mathbb{R} ^{n}}$ , and let ${M := M_{\{g_1, \ldots, g_s\}}}$ be a finitely generated quadratic module in ${\mathbb{R} [\underline{X}]}$ . We investigate the following question: When is the cone Psd(K) (of polynomials nonnegative on K) included in the closure of M? We give an interpretation of this inclusion with respect to representing continuous linear functionals by measures. We discuss several examples; we compute the closure of ${M = \sum \mathbb{R} [\underline{X}]^{2}}$ with respect to weighted norm-p topologies. We show that this closure coincides with the cone Psd(K) where K is a certain convex compact polyhedron. 相似文献
143.
Prof. Dr. Abdolraouf Samadi‐Maybodi Seyed Naser Azizi S. Masoomeh Pourali Salma Ehsani Tilami 《无机化学与普通化学杂志》2012,638(1):214-219
Bismuth‐modified zeolite‐P (Bi‐ZP) was synthesized by hydrothermal methods during the phase transformation of analcime to zeolite‐P. The evolution of phase transformation of pure analcime to Bi‐ZP was investigated. The results showed that bismuth atoms were incorporated into the framework of the microporous zeolite‐P. The effect of various Bi/Al (0–3) and Si/Bi (1–5) mole ratios on the synthesis of bismuth modified zeolite were studied by X‐ray diffraction (XRD) technique and FT‐IR spectroscopy. Evolution of the growth process of Bi‐ZP spheres was carried out at different time intervals with XRD patterns and FE‐SEM images. The energy dispersive X‐ray (EDX) spectrum indicated the existence of bismuth atoms in the synthesized Bi‐ZP. Framework substitutions of bismuth were evidenced by a set of complementary characterizations such as diffusive reflectance UV/Vis (DRS) and Raman spectroscopy on the synthesized Bi‐ZP (Si/Bi = 1). 相似文献
144.
A sensitive time- resolved luminescence method for the determination of meloxicam (MX) in methanol and in aqueous solution
is described. The method is based on the luminescence sensitization of europium (Eu3+) by formation of ternary complex with MX in the presence of 1,10- phenanthroline as coligand, Tween-80 as surfactant and
gadolinium ion as a co-luminescence reagent. The signal for Eu- MX-1, 10- phenanthroline is monitored at λex = 360 nm and λem = 620 nm. Optimum conditions for the formation of the complex in aqueous system were 0.01 M TRIS buffer, pH 8.0, 1,10- phenanthroline
(6.0 × 10−6 M) , Gd3+ (7.0 × 10−6 M), Tween-80 (0.28%) and 1.75 mM of Eu3+ which allows the determination of 20–800 ppb of MX with limit of detection (LOD) of 7 ppb. The relative standard deviations
of the method range between 0.1 and 1.1% indicating excellent reproducibility of the method. The proposed method was successfully
applied for the assay of MX in pharmaceutical formulations, plasma and in urine samples. Average recoveries of 99.8 ± 1.1%,
100.2 ± 0.9% and 100.9 ± 1.1% were obtained for MX in tablet, plasma and urine sample respectively. 相似文献
145.
Acousto-optic imaging is based on light interaction with focused ultrasound in a scattering medium. Thanks to photorefractive holography combined with pulsed ultrasound, we perform a time-resolved detection of ultrasound-modulated photons in the therapeutic window (780 nm). A high-gain SPS:Te crystal is used for this purpose and enables us to image through large optical thickness (500 mean free paths). We are able to generate three-dimensional (3D) acousto-optic images by translating a multielement ultrasound probe in only one direction. A 3D absorbing object is imaged through a 3 cm thick phantom. 相似文献
146.
In the present paper, we are mainly concerned with the existence of a Riesz basis related to the Gribov operator 相似文献
$$\begin{aligned} A^{*2}A^2+\varepsilon (A^* A + A^* (A + A^* )A), \end{aligned}$$ 147.
Salma Kiani Richard J. Staples Alan B. Packard 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):m593-m595
The dimeric title copper(II) complex, diaqua‐1κO,2κO‐bis[3,9‐dimethyl‐6‐(2‐pyridylmethyl)‐4,8‐diazaundeca‐3,8‐diene‐2,10‐dione dioximato(1?)]‐1k4N2,N4,N8,N10;1:2κ5O2:N2,N4,N8,N10‐dicopper(II) diperchlorate, [Cu2(C17H24N5O2)2](ClO4)2, crystallizes with one Cu atom in a square‐pyramidal environment and the other Cu atom displaying a distorted octahedral coordination. In each case, the four N atoms in the core of the ligand (two imine and two oxime N atoms) form the base of the pyramid, with a water molecule at an apex. The two parts of the dimer are linked by an interaction [2.869 (2) Å] between one of the Cu atoms and one of the oxime O atoms coordinated to the second Cu atom, and also by a hydrogen bond between the apical water molecule on the second Cu atom and the pyridyl N atom from the coordination sphere of the first Cu atom. The pyridyl N atoms of the lariat arms are not coordinated to either of the Cu atoms. Thus, this potentially pentadentate ligand is only tetradentate when coordinated to CuII. 相似文献
148.
Let :=. The following are known: two -sets of power are isomorphic. Let >0. Two ordered divisible Abelian groups that are -sets of power are isomorphic, two real closed fields that are -sets of power are isomorphic. The following is shown: (1) there exist 2 nonisomorphic ordered Abelian groups (respectively ordered fields) that are -sets of power ; (2) there exist 2 nonisomorphic ordered divisible Abelian groups (respectively real closed fields) of power all having the same order type; (3) there exist 2 nonisomorphic ordered divisible Abelian groups (respectively real closed fields) that are -sets having the same order type. 相似文献
149.
Mohammad Ali Kamyabi Hoda Mohammadian Salma Jadali Mohsen Moharramnezhad 《Electroanalysis》2019,31(8):1484-1493
In this project, Pt/NiO?GO nanocatalyst is grown on nickel foam (NF) and, its catalytic activity towards electrochemical oxidation of methanol in acidic media is studied. The first step is devoted to the synthesis of NiO?GO support by a hydrothermal method. Then Pt nanoparticles (~34.3 nm) are electrodeposited on this supporting material. Hydrothermal and electrochemical deposition conditions are optimized. Surface of modified NF was inspected for physical characterization and Chemical composition by some techniques such as field emission scanning electron microscopy (FESEM), energy‐dispersive X‐ray spectra (EDS), and X‐ray diffraction (XRD). In the electrochemical section, the catalytic performance of Pt/NiO?GO/NF towards methanol oxidation is investigated by cyclic voltammetry and chronoamperometry measurements. The electrochemical impedance spectroscopy (EIS) is elected to deliberate charge transfer resistance on the catalyst surface. Mass activity, electrochemical surface area (ECSA) and durability of prepared catalysts are compared with commercial Pt/C. Deliberations prove the superiority of Pt/NiO?GO/NF towards methanol oxidation in acidic media. The Superior quality of synthesized nanocatalyst that is attributed to the synergetic effect of the NiO?GO support material and Pt nanoparticles, indicate that Pt/NiO?GO/NF can be successfully used as the anode in the direct methanol fuel cell (DMFC). 相似文献
150.
Salma Charfi Aref Jeribi Rihab Moalla 《Mathematical Methods in the Applied Sciences》2014,37(4):597-608
The main goal of this paper is to give a characterization of Wolf, Schechter, and Browder essential spectra of (2 × 2) matrix operator on a Banach space. Furthermore, we apply the obtained results to transport equations. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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