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171.
The new synthesized ligand (DADMBTZ = 2,2′‐diamino‐5,5′‐dimethyl‐4,4′‐bithiazole), which is mentioned in this text, is used for preparing the two new complexes [Zn(DADMBTZ)3](ClO4)2. 0.8MeOH.0.2H2O ( 1 ) and [Cd(DADMBTZ)3](ClO4)2 ( 2 ). The characterization was done by IR, 1H, 13C NMR spectroscopy, elemental analysis and single crystal X‐ray determination. In reaction with DADMBTZ, zinc(II) and cadmium(II) show different characterization. In 2 , to form a tris‐chelate complex with nearly C3 symmetry for coordination polyhedron, DADMBTZ acts as a bidentate ligand. In 1 , this difference maybe relevant to small radii of Zn2+ which make one of the DADMBTZ ligands act as a monodentate ligand to form the five coordinated Zn2+ complex. In both 1 and 2 complexes the anions are symmetrically different. 1 and 2 complexes form 2‐D and 3‐D networks via N‐H···O and N‐H···N hydrogen bonds, respectively. 相似文献
172.
In this paper we introduce new generalized fuzzy Lie ideals of Lie algebras and study some of their important properties.We characterize these generalized Lie ideals of Lie algebras by their level subsets.Some characterization of the generalized fuzzy Lie ideals of Lie algebras are also established. 相似文献
173.
174.
Akram Aldroubi David Larson Wai-Shing Tang Eric Weber 《Transactions of the American Mathematical Society》2004,356(12):4767-4786
We consider frames arising from the action of a unitary representation of a discrete countable abelian group. We show that the range of the analysis operator can be determined by computing which characters appear in the representation. This allows one to compare the ranges of two such frames, which is useful for determining similarity and also for multiplexing schemes. Our results then partially extend to Bessel sequences arising from the action of the group. We apply the results to sampling on bandlimited functions and to wavelet and Weyl-Heisenberg frames. This yields a sufficient condition for two sampling transforms to have orthogonal ranges, and two analysis operators for wavelet and Weyl-Heisenberg frames to have orthogonal ranges. The sufficient condition is easy to compute in terms of the periodization of the Fourier transform of the frame generators.
175.
The optimized geometries, molecular properties, and stabilities of new noble gas molecules, XXeOH (X = F, Cl, Br, and I), were studied using CCSD, MP2, CAM-B3LYP, and WB97XD methods and large basis sets. All XXeOH molecules showed equilibrium structures with Cs symmetry. The results also showed that some bonds in XXeOH could be presented as a typical ionic bond. An alteration in ion-pair character was observed for IXeOH, showing two OH ? and IXe + parts, while in other molecules, they could be presented as XeOH + and X ? . Two decomposition routes were proposed for these molecules that showed high exothermic reactions. However, despite their low thermodynamic stabilities, their decomposition rate constants were small and all molecules (except BrXeOH) had high kinetic stabilities, indicating the possibility for identification and characterization of these molecules. However, in addition to the calculation of their vibrational frequencies, NBO atomic charges, and hybridizations, the bonding properties of XXeOH molecules were studied by AIM calculations (to calculate electron densities, bond elipticities, and Laplacian of electron densities) and second-order intramolecular perturbation energies using NBO calculations. Moreover, the ease of formations and relative stabilities of XXeOH molecules were compared using heats of formations, Gibbs free energies of formations and isodesmic reactions. These calculations showed that the stability of XXeOH molecules was decreased from F to I. 相似文献
176.
Fatemeh Pourasgharian Roudsari Mohammad Reza Mehrnia Akram Asadi Zohreh Moayedi Reza Ranjbar 《Applied biochemistry and biotechnology》2014,172(1):131-140
In this work, capability of the green microalga (MA), Chlorella vulgaris, in treating synthetic anaerobic effluent of municipal wastewater was investigated. While pure C. vulgaris (100 % MA) provided maximum soluble chemical oxygen demand (sCOD) and N???NH 4 + removal efficiencies of 27 and 72 % respectively, addition of activated sludge (AS) to MA in different mass ratios (91, 80, 66.7, 9 % MA) improved wastewater treatment efficiency. Thus giving maximum sCOD and N???NH 4 + removal efficiencies 85 and 86.3 % (for MA/AS?=?10/1), respectively. Utilizing AS without C. vulgaris, for treating the synthetic wastewater resulted in 87 % maximum sCOD and 42 % maximum N???NH 4 + removal efficiencies. Furthermore, algal growth and specific growth rates were measured in the systems with microalga as the dominant cellular population. As a result, faster algal growth was observed in mixed systems. Specific growth rate of C. vulgaris was 0.14 (day?1) in 100 % MA and 0.39 (day?1) in 80 % MA. Finally, data gathered by online measurement of dissolved oxygen indicate that algae-activated sludge mixture improves photosynthetic activity of examined microalga strain during anaerobic effluent treatment. 相似文献
177.
The reaction of C10H7-1-N(PPh2)2 ( 1 ) with two equivalents of CuI in acetonitrile resulted in the formation of octahedron Cu4I4[ 1 ]2 complex ( 2 ). The crystal structure of 2 showed it adopted a rare octahedral arrangement. The rectangular Cu4 plane is μ4-capped by two of the iodides and is placed in axial positions above and below the Cu4-plane form an octahedron, whereas the other two iodides are bonded to two copper atoms in a μ2-fashion. The luminescence of complex 2 arises from a triplet halide-to-ligand charge transfer (3XLCT) excited state and 3CC (Cu4I4 cluster-centered) excited state are not involved in the luminescence by the rigid bidentate ligand 1 in spite of the short CuI–CuI bond length. Complex 2 was identified and characterized by multinuclear NMR (1H, 13C, 31P NMR) and IR spectroscopy. Crystal structure determinations of 1 and 2 were carried out. 相似文献
178.
We report on a fast, simple and accurate method for the determination of proline in urine samples by employing a nanostructured film of conducting polypyrrole for electrochemically controlled solid-phase microextraction, and ion mobility spectrometry (IMS) for detection. This method has the advantages of simple sample preparation and a sensitivity of IMS to proline that is higher than that for other amino acids. The calibration curve is linear in the range of 0.5–60 μg L?1 (4–521 nmol L?1), and the detection limit is 0.2 μg L?1. The electrochemical potentials for uptake and release were optimized. The method was successfully applied to the clean-up and quantitation of trace amounts of proline in urine samples. Figure
Proline determination by electrochemically controlled solid phase microextraction coupled to ion mobility spectrometry 相似文献
179.
Joong-Ho Kwon Jae-Jun Ahn Kashif Akram Ik-Jae Son Sang-O Lee 《Analytical and bioanalytical chemistry》2013,405(12):4225-4234
Two kinds (20 each) of gamma-irradiated (0, 5, and 10 kGy) tea samples, blended powders and packed in sachets (tea bags), were investigated using photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance spectroscopy (ESR) to identify their irradiation status. PSL-based rapid screening was possible for all the control samples except for one packed and two powdered samples. The irradiated samples presented a good dose-dependent PSL count except two powdered samples with very low PSL sensitivity. TL analysis provided the most reliable results, in which all the irradiated samples were identified using a well-defined high-intensity TL glow curve in a temperature range of 150–250 °C. The TL results were also confirmed by determining the TL ratio (TL1/TL2), which was <0.1 in all the non-irradiated samples and >0.1 in the irradiated ones. ESR spectroscopy was effective for only 3 packed and 6 powdered samples showing the radiation-induced cellulosic and sugar radical signals, respectively. Figure
TL-based detection of irradiated teas 相似文献
180.
Sayed Yahya Kazemi Akram Sadat Hamidi Mohammad Javad Chaichi 《Journal of the Iranian Chemical Society》2013,10(2):283-288
Transport of Pb(II) ion from equimolar aqueous solutions of Pb(II), Cu(II) and Cd(II) as well as from aqueous solutions containing only Pb(II) source phase (Cmetal = 1.0 × 10?4 mol L?1) through bulk liquid membranes containing crown ether and oleic acid as carrier has been investigated. The initial fluxes of transported metal ions depend on the hydrophile–lipophile balance (HLB) and molar volumes (Vx) of crown ethers. The initial fluxes of Pb(II), Cu(II), and Cd(II) decrease with increase of HLB value for azacrown ether, i.e., tetraaza-14-crown-4 (A414C4), L1 > benzo-15-crown-5 (B15C5), L2 > 4′-Aminobenzo-15C5, L3 > nitrobenzo-15-crown-5 (NB15C5), L4. The selectivity of the metal ions showed the following separation factors (SF): SFPb–Cu = 2.15, SFCu–Cd = 2.10, SFPb–Cd = 4.52. The highest transport recovery for Pb(II) was observed for L1 (99.3 %). 相似文献