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11.
Ján Medved’ Milan Kališ Ingrid Hagarová Peter Matúš Marek Bujdoš Jana Kubová 《Chemical Papers》2008,62(2):168-175
Determination of thallium in polluted environmental samples and their extracts obtained by a modified BCR three-step sequential
extraction procedure was used to study thallium distribution and mobility in the monitored polluted area affected by acidification
(Šobov, Central Slovakia). The results of fractionation applied to 5 soil certified reference materials and 14 environmental
samples show that the vast majority of thallium occurred in the residual fraction. This means that highly toxic thallium is
strongly entrapped in the parent rock materials remains immobile and its environmental toxicity is therefore reduced. The
limit of detection for thallium in the studied fractions was lower than 0.050 mg kg−1, the precision (RSD) of the ultratrace determination of thallium in the studied fractions was better than 17 % and the accuracy
of the used method was verified by analyzing certified reference materials.
Presented at the XVIIIth Slovak Spectroscopic Conference, Spišská Nová Ves, 15–18 October 2006. 相似文献
12.
The kinetics of oxidation of some aldoses, amino sugars and methylated sugars by osmium (VIII) have been studied spectrophotometrically in alkaline medium. The reactions are first‐order with respect to both [sugar]≤9.0×10−3 mol dm−3 and [OH−]≤10.0×10−2 mol dm−3 but tends toward zero order with respect to each at higher concentration. Activation parameters of the reactions have been calculated and plausible reaction mechanisms have been suggested. © 1999 John Wiley & Sons, Inc. Int J Chem Kinet 31: 477–483, 1999 相似文献
13.
Bhaskar Kandagatla Vetukuri Venkata Naga Kali Vara Prasada Raju Ganta Madhusudhan Reddy Sirigiri Chandrakanth Rao Javed Iqbal Rakeshwar Bandichhor Srinivas Oruganti 《Tetrahedron letters》2012,53(52):7125-7127
Agomelatine was synthesized from 8-aminonaphthalen-2-ol by diazotization-iodination, formylation, C–C bond formation by nitroaldol and Pd/C hydrogenation of β-nitrovinylnaphthalene followed by N-acetylation. The route reported employs readily and commercially viable starting materials and reagents, and can potentially be utilized for process synthesis of agomelatine. 相似文献
14.
Kinetics of the oxidation of methanol and mono-deutero-methanol by Cr(VI) over a wide range of temperature (25–40°) have been studied in perchloric acid medium at constant ionic strength (μ = 1.0 M) adjusted with sodium perchlorate. Each reaction is first order with respect to the substrate and dichromate concentrations but the order with respect to [H+] is nearly 3 in each case. Both these reactions take place at almost the same rate under identical experimental conditions. The activation parameters of the reactions are not widely different and the values of ΔH3 and ΔS3 for the oxidation of methanol are 79.5 kJ mole -1 and - 38.1 J deg-1 mole-1 respectively, whereas the corresponding values for the deuterated compound are 83.8 kJ mole-1 and -23.9 J deg-1 mole-1. The probable mechanism of the reactions is discussed. 相似文献
15.
Summary The reaction between sulphite and gold(III) in hydrochloric acid medium has been studied; an initial complex is formed prior to electron transfer. The reaction rate is inversely proportional to the hydrogen ion concentration and the reaction appears to proceed through the intermediate formation of a free radical which reacts with gold(III) to give the products. Evidence for the formation of dithionate together with sulphate is presented. 相似文献
16.
In 1951, Dvoretzky, Wald and Wolfowitz (henceforth DWW) showed that corresponding to any mixed strategy into a finite action space, there exists a pure-strategy with an identical integral with respect to a finite set of atomless measures. DWW used their theorem for purification: the elimination of randomness in statistical decision procedures and in zero-sum two-person games. In this short essay, we apply a consequence of their theorem to a finite-action setting of finite games with incomplete and private information, as well as to that of large games. In addition to simplified proofs and conceptual clarifications, the unification of results offered here re-emphasizes the close connection between statistical decision theory and the theory of games.A first draft of this paper was completed when Khan and Rath were visiting the Institute for Mathematical Sciences at the National University of Singapore in August 2003; they thank the Institute for supporting their visit. A preliminary version was presented at the Midwest Economic Theory Conference held at Indiana University, Bloomington in October 2003; the authors are grateful to Eric Balder, Robert Becker, William Thomson and Myrna Wooders for questions and helpful suggestions. 相似文献
17.
Kali P. Rath 《International Journal of Game Theory》1998,27(4):525-537
This paper examines Hotelling's model of location with linear transportation cost. Existence of pure strategy subgame perfect
equilibria in the infinitely repeated price game with fixed locations is proved. These subgame perfect equilibria have a stick
and carrot structure. Given firm locations, there are discount factors sufficiently high that there is a subgame perfect equilibrium
with a two-phase structure. Given the discount factors, there are stationary subgame perfect equilibria for a wide range of
locations. However, for some pairs of location, no symmetric simple penal code exists, all subgame perfect profiles are nonstationary,
and there is only one seller in the market in infinitely many periods.
Received July 1996/Final version May 1998 相似文献
18.
A simple pictorial algorithm for factorisation of symmetric chemical graphs (weighted and unweighted) leading to simultaneous
determination of their eigenvalues and eigenvectors has been devised. The method does not require group-theoretical techniques
(viz. identification of the point group of the species under study, formation of symmetryadopted linear combinations using
character tables etc.). It requires consideration of only one symmetry element, e.g., a reflection plane and is based on elementary
row and column operations which keep the secular determinant of the adjacency matrix unchanged (except possibly for a multiplicative
constant). 相似文献
19.
Gupta Kalyan Kali Sen Begum Bilkis Ara Ghosh Sakti Prosad 《Transition Metal Chemistry》1998,23(3):295-299
Oxidations of glycolaldehyde (GA) to glyoxal by osmium(VIII), iridium(IV) and platinum(IV) have been investigated in aqueous
solution, and the orders with respect to each [reactant] determined. The reaction involving iridium(IV) takes place through
intermediate formation of free radicals in a MeCO2Na-MeCO2H buffer medium, whereas a one-step two-electron transfer process occurs in the oxidations by OsVIII and PtIV in an alkaline medium. Mechanisms consistent with the experimental findings are proposed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
20.
Zbigniew Koczorowski Anna Kalińska Zbigniew Figaszewski 《Journal of Electroanalytical Chemistry》1982,139(2):303-307
Measurements have been made of an alternating voltage appearing as a result of mechanical vibrations of a water-nitrobenzene interface in a capillary. It has been found that a sharp minimum appears on the plot of alternating voltage vs. polarization potential; it probably corresponds to the potential of zero charge. The measuring apparatus is presented. 相似文献