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61.
Summary A group of mixed-tris chelates of osmium(III) and osmium(IV) of type [OsAQ2]0/1 + [HA = glycine (glyH), picolinic acid (PicH) and quinaldic acid (qndH); HQ = 8-quinolinol] were prepared and characterized by physicochemical, magnetic and spectroscopic methods. The complexes exhibit several spin-allowed and spin-forbidden absorption bands and shoulders in the 200–700 nm region. The new chelates are electroactive and display nearly reversible OsIV-OsIII and OsIII-OsII couples in the ca. –1.1 to +0.3 V range versus s.c.e. The stability of metal oxidation states is discussed in terms of the electrochemical results. 相似文献
62.
63.
Optics is regarded undoubtedly a potential and successful candidate in information and data processing because of its inherent
parallelism. In last few decades several all-optical data processors, algebraic processors, arithmetic processors are proposed.
Here in this communication the authors propose a completely new scheme for implementing binary data arithmetic in 2’s Complement
method which is the most advantageous among all other established subtraction methods. To implement it we use non-linear material
massively. 相似文献
64.
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66.
Precise conductance measurements of solutions of lithium chloride, lithium bromide, lithium iodide, lithium perchlorate, lithium tetrafluoroborate, lithium hexafluoroarsenate, tetrabutylammonium bromide, and tetrabutylammonium tetraphenylborate in N,N-dimethylacetamide are reported at 25°C in the concentration range 0.005–0.015 mol-dm–3. The conductance data have been analyzed by the 1978 Fuoss conductance equation in terms of the limiting molar conductance (0), the association constant (K
a), and the association diameter (R). The limiting ionic conductances have been estimated from an appropriate division of the limiting molar conductivity of the reference electrolyte Bu4NBPh4. Slight ionic association was found for all these salts in this solvent medium. The results further indicate significant solvation of Li+ion, while the other ions are found to be unsolvated in N,N-dimethylacetamide. 相似文献
67.
Precise conductance measurements have been performed for lithium perchlorate, lithium tetrafluoroborate, lithium hexafluoroarsenate, sodium perchlorate, and sodium tetraphenylborate in 2-methoxyethanol–water mixtures at four different mole fractions, i.e., 0.056, 0.136, 0.262, and 0.486 of 2-methoxyethanol (69.73 D 26.55) at 25°C in the concentration range 0.0004–0.0642 mol-dm–3. The limiting molar conductivity °, the association constant K
A, and the association distance R for the solvent mixtures have been evaluated from the conductance concentration data using the 1978 Fuoss conductance equation. The single-ion conductances have been estimated using the reference electrolyte tetrabutylam-monium tetraphynylborate(Bu4NBPh4). The analysis of the data indicates that for most salts ion association is appreciable in the solvent mixtures with a mole fraction of the cosolvent of 0.262 or higher. The results have been interpreted in terms of ion-solvent interactions and structural changes in the mixed solvent media. 相似文献
68.
Some new tetradentate ligands with a NNOS coordination sphere were prepared and their corresponding nickel(II) complexes were synthesized and characterized by elemental analysis, IR, 1H NMR, UV–Vis and mass spectrophotometry. The thermodynamic formation constants of the complexes were measured spectrophotometrically, at a constant ionic strength of 0.1 M (NaClO4) at 25 °C in DMF solvent. The trend of the complex formation for nickel is as follows: 相似文献
69.
Elshani S Chun S Amiri-Eliasi B Bartsch RA 《Chemical communications (Cambridge, England)》2005,(2):279-281
New lipophilic acyclic polyethers with two N-(X)sulfonyl carbamoyl groups of "tunable" acidity exhibit remarkable selectivity for Ba2+ over other alkaline earth metal ions in competitive solvent extraction and transport across polymer inclusion membranes. 相似文献
70.
Bijan?SahaEmail author G.?N.?Shikin 《International Journal of Theoretical Physics》2005,44(9):1459-1494
We consider a system of minimally coupled nonlinear spinor and scalar fields within the scope of a plane-symmetric gravitational
field. The gravitational field plays crucial role in the formation of soliton-like solutions, i.e., solutions with limited
total energy, spin, and charge. The change of the sign of the scalar field energy density of the system in question realizes
physically if and only if the scalar charge does not exceed some critical value. In case of spinor field no such restriction
on its parameter occurs. The choice of spinor field nonlinearity leads to the elimination of scalar field contribution to
the metric functions, but leaves its contribution to the total energy unaltered. The spinor field is more sensitive to the
gravitational field than the scalar field. 相似文献