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排序方式: 共有344条查询结果,搜索用时 15 毫秒
1.
Boris‐Marko Kukovec Zora Popovi Gordana Pavlovi 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(9):m389-m391
In the title compound, [Cd(C7H6NO2)2]n, the CdII ion has a distorted octahedral geometry. The 6‐methylpyridine‐2‐carboxylate anions are perpendicular to one another and act as bidentate and bridging ligands. Two carboxylate O atoms bridge the CdII ions, forming centrosymmetric dinuclear units. These units are further connected via carboxylate O atoms into a one‐dimensional polymeric chain which extends in the [100] direction. 相似文献
2.
Hussain HH Babic G Durst T Wright JS Flueraru M Chichirau A Chepelev LL 《The Journal of organic chemistry》2003,68(18):7023-7032
We are attempting to develop novel synthetic antioxidants aimed at retarding the effects of free-radical induced cell damage. In this paper we discuss the design strategy and report the synthesis of seven novel antioxidants, including six catechols and a benzylic phenol. The bond dissociation enthalpy (BDE) for the most active (weakest) OH bond in each molecule was calculated by theoretical methods, as well as the BDE for the semiquinone radical. Reaction rates with the nitrogen-centered free radical DPPH(*) were measured in ethyl acetate. The log of k(DPPH) for bimolecular reaction correlated well with the primary BDE. The correlation between rate constants and calculated BDEs shows that the BDE is a good predictor of antioxidant activity with DPPH(*), suggesting that our design criteria are useful and that these compounds should undergo further testing in cell cultures and in animal models. 相似文献
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A kinetic method for the determination of selenium(IV) traces is proposed, based on its inhibitory action on the oxidation of Nile Blue A by hydrogen peroxide in phosphate buffer (pH 10.5). A linear dependence was established between the rate of the proposed indicator reaction and selenium concentration in the range 9.5 × 10–2-1.58 ng cm–3. The experimental conditions of maximal selenium effect were established. Selenium, determined by the tangent method, was determined at concentrations over the range 0.22–1.26 ng cm–3, with relative standard deviations up to 4.5%. The reaction rate was followed spectrophotometrically. The effect of foreign ions on the accuracy of this method was also investigated. The method was applied to the determination of selenium in pharmaceutical preparations and wheat flour. 相似文献
5.
Djordje Vlaović Gordana Ćetković Ivan Juranić Jelica Balaž Stevan Lajšić Dejan Djoković 《Monatshefte für Chemie / Chemical Monthly》1990,121(11):931-939
Summary The syntheses andin vitro antibacterial and antifungal evaluation of certain (5-nitro-2-furyl)azomethines with different heterocyclic nuclei are described.
Die Anwendung von Lävulinsäure und 5-Nitro-2-furylmethylendiacetat in der Totalsynthese einiger neuer biologisch aktiver (5-Nitro-2-furyl)azomethine
Zusammenfassung Es wird die Synthese und diein-vitro-antibakterielle und antifungale Wirksamkeit für bestimmte (5-Nitro-2-furyl)azomethine mit verschiedenen heterocyclischen Kernen beschrieben.相似文献
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Nebojša Banjac Gordana Ušćumlić Nataša Valentić Dušan Mijin 《Journal of solution chemistry》2007,36(7):869-878
Absorption spectra of eight 3-substituted-5,5-diphenylhydantoins have been recorded in fourteen solvents in the range 200–400 nm.
The effect of solvent dipolarity/polarizability and solvent/solute hydrogen bonding interactions are analyzed by means of
the linear solvation energy relationship (LSER) concept proposed by Kamlet and Taft. The lipophilic activity of the investigated
hydantoins was estimated by the calculation of log 10
P values with the Advanced Chemistry Development Software. The calculated values of log 10
P were correlated with the ratio of the contributions of specific solvent interactions, and, by employing the linear dependence
thus obtained, the pharmacological activity of the studied hydantoin derivatives is discussed. 相似文献
8.
Snezana S.?MiticEmail author Gordana Z.?Miletic Aleksandra N.?Pavlovic Snezana B.?Tosic 《Monatshefte für Chemie / Chemical Monthly》2004,135(8):927-936
Summary. A new selective, sensitive, and simple kinetic method is developed for the determination of trace amounts of chromium (VI). The method is based on the catalytic effect of Cr(VI) on the reaction of sodium pyrogallol-5-sulphonate (PS) with hydrogen peroxide. The reaction is followed spectrophotometrically by tracing the oxidation product at 437nm within 1min after addition of H2O2. The optimum reaction conditions are PS (1.32·10–3mol·dm–3), H2O2 (0.32mol·dm–3), HClO4 (2.6·10–3mol·dm–3) at 25°C. Following this procedure, chromium (VI) can be determined with a linear calibration graph up to 0.25ng·cm–3 and a detection limit of 0.024ng·cm–3, based on the 3 criterion. The interference effect of several species was also investigated and it was found that the most common cations and anions do not interfere with the determination. The developed procedure was successfully applied to the determination of Cr(VI) and total Cr in river waters and total Cr in herbal samples. 相似文献
9.
Gordana A. Milovanović 《Microchemical Journal》1983,28(3):437-457
A review on the determination of organic substances by kinetic-catalytic methods of analysis is given.Methods based on homogeneous catalyzed solution reactions as well as those based on heterogeneous catalyzed electrode reactions are discussed. 相似文献
10.