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81.
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83.
Gordana Ćirić-Marjanović Igor Pašti Nemanja Gavrilov Aleksandra Janošević Slavko Mentus 《Chemical Papers》2013,67(8):781-813
Polyaniline (PANI) and polypyrrole (PPY) undergo carbonisation in an inert/reduction atmosphere and vacuum, yielding different nitrogen-containing carbon materials. This contribution reviews various procedures for the carbonisation of PANI and PPY precursors, and the characteristics of obtained carbonised PANI (C-PANI) and carbonised PPY (C-PPY). Special attention is paid to the role of synthetic procedures in tailoring the formation of C-PANI and C-PPY nanostructures and nanocomposites. The review considers the importance of scanning and transmission electron microscopies, XPS, FTIR, Raman, NMR, and EPR spectroscopies, electrical conductivity and adsorption/desorption measurements, XRD, and elemental analyses in the characterisation of C-PANIs and C-PPYs. The application of C-PANI and C-PPY in various fields of modern technology is also reviewed. 相似文献
84.
We define the relative Tits form number W(G, V) of a valued bigraph G at a vertex v and derive some basic properties. We give a detailed analysis of the case when W (G,V) ≥½. The properties of these numbers were used without proof in the classification of Auslander algebras of finite representation type [IPTZ] 相似文献
85.
Vesna M. Djinović Verica V. Glodjović Gordana P. Vasić Vladimir Trajković Olivera Klisurić Slobodanka Stanković Tibor J. Sabo Srećko R. Trifunović 《Polyhedron》2010,29(8):1933-1938
The syntheses of two novel platinum(IV) complexes of formula [PtX2(S,S-eddp)]·nH2O (S,S-eddp = ethylenediamine-N,N′-di-S,S-2-propanoate ion, X = chlorido (1) or bromido (2), n = 4, 0) are reported. The complexes have been obtained by direct reaction of corresponding potassium hexahalogenidoplatinate(IV) with neutralized ethylenediamine-N,N′-di-S,S-2-propanoic acid (H2-S,S-eddp). The complexes were characterized by elemental analysis, infrared, 1H and 13C NMR spectroscopy. The spectroscopically predicted geometrical configurations of the obtained complexes were confirmed by X-ray analyses of the crystal structures of the s-cis-[Pt(S,S-eddp)Cl2]·4H2O and uns-cis-[Pt(S,S-eddp)Br2]. These complexes displayed significantly lower in vitro cytotoxicity in comparison to cisplatin. 相似文献
86.
Gordana P. Radi?Verica V. Glo?ovi? Ivana D. Radojevi?Olgica D. Stefanovi? Ljiljana R. ?omi?Zoran R. Ratkovi? Arto ValkonenKari Rissanen Sre?ko R. Trifunovi? 《Polyhedron》2012,31(1):69-76
S-Alkyl (R = benzyl, methyl, ethyl, propyl and butyl) derivatives of thiosalicylic acid and the corresponding palladium(II) complexes were prepared and their structures were proposed on the basis of infrared, 1H and 13C NMR spectroscopy. The cis geometrical configurations of the isolated complexes were proposed on the basis of an X-ray structural study of the bis(S-benzyl-thiosalicylate)-palladium(II), [Pd(S-bz-thiosal)2] complex.Antimicrobial activity of the tested compounds was evaluated by determining the minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) in relation to 26 species of microorganisms. The tested ligands, with a few exceptions, show low antimicrobial activity. The palladium(II) complexes, [Pd(S-R-thiosal)2], have statistically significant higher activity than the corresponding ligands. The complexes [Pd(S-et-thiosal)2] and [Pd(S-pro-thiosal)2] displayed the strongest activity amongst the all tested compounds. The palladium(II) complexes show selective and moderate antibacterial activity and significant antifungal activity. The most sensitive were Aspergillus fumigatus and Aspergillus flavus. 相似文献
87.
Suzana Samaržija-Jovanović Vojislav Jovanović Gordana Marković Milena Marinović-Cincović 《Journal of Thermal Analysis and Calorimetry》2009,98(1):275-283
The influence of two types of carbon black filler N330 and N990 (primary particle size 46 nm and >230 nm) on elastomeric composites
based on acrylonitrile-butadiene rubber (NBR) have been investigated. The activation energy (E
a) were determined from two high temperature rheokinetic curves (T
1 = 180 °C and T
2 = 190 °C). For tensile testing, the compounds with different content of carbon black were vulcanized in a hydraulic press
at 150 °C. The stress-strain experiments were performed before and after ageing the specimens in an air-circulating oven at
100 °C for 168 h. The thermal degradation and thermal stability of carbon black filled NBR rubber was investigated by thermogravimetric
analysis in a flowing nitrogen atmosphere at a heating rate of 10 °C/min. 相似文献
88.
Evgenija A. Djurendić Sanja V. Dojčinović-Vujašković Marija N. Sakač Emilija Dj. Jovin Vesna V. Kojić Gordana M. Bogdanović Olivera R. Klisurić Slobodanka M. Stanković Dušan V. Lazar Laslo Fabian Katarina M. Penov-Gaši 《Structural chemistry》2010,21(1):67-78
New salicylic (2-hydroxybenzoic) acid derivatives 1–6 were prepared by conventional heating or microwave irradiation of a mixture consisting of methyl salicylate and the corresponding amino alcohol (2,2′-dihydroxydiethylamine, 2,2′,2″-trihydroxytriethylamine or N-phenyl-2,2′-dihydroxydiethylamine) and metallic sodium as catalyst. For compounds 1, 3, and 5 X-ray structure analysis was performed, as well as molecular mechanics calculations (MMC), to define their conformation in terms of their energy minima. Comparison of crystal and MMC structures for these three compounds (1, 3, and 5) revealed that the intramolecular hydrogen bonds play an important role, stabilizing conformation of the most part of the molecule. The antioxidant activity and cytotoxicity of the synthesized derivatives were evaluated in a series of in vitro tests. The newly synthesized compounds exhibited strong activity against hydroxyl radical, as well as promising lipid peroxidation inhibition. The study showed that the electronic effects of the groups at the N atom are responsible for neutralization of the OH radical, i.e., antioxidant activity. Compounds 1–3 exhibited sub-micromolar cytotoxicity against HeLa S3, whereas compounds 1, 3 and 5 efficiently inhibited the growth of PC3 cells. 相似文献
89.
A Alimmari DA Mijin R Vuki Evi B Bo I NA Valenti V Vitnik E Vitnik G U Umli 《Chemistry Central journal》2012,6(1):71
ABSTRACT: BACKGROUND: A series of some novel arylazo pyridone dyes was synthesized from the corresponding diazonium salt and 6-hydroxy-4-phenyl-3-cyano-2-pyridone using classical reaction for the synthesis of the azo compounds. RESULTS: The structure of the dyes was confirmed by UV-vis, FT-IR, 1H NMR, 13C NMR spectroscopic technique and elemental analysis. The solvatochromic behaviour of the dyes was evaluated with respect to visible absorption properties in various solvents. CONCLUSIONS: The azo-hydrazone tautomeric equilibration is found to depend upon substituents as well as on solvents. The geometry data of the investigated dyes were obtained using DFT quantum-chemical calculations. The obtained calculational results are in very good agreement with the experimental data. 相似文献
90.
Anife Ahmedova Petja Marinova Gordana Pavlovi? Maya Guncheva Neyko Stoyanov Mariana Mitewa 《Journal of the Iranian Chemical Society》2012,9(3):297-306
A series of seven 2-cinnamoyl-1,3-indandiones and their metal(II) complexes were synthesized and characterized by means of spectroscopic (IR, NMR, electron absorption and emission spectroscopy) and/or single-crystal X-ray diffraction methods. The optical spectra of the organic compounds show very strong absorption in the visible region and weak fluorescence with moderate to strong Stokes shift. The effect of concentration, water addition and metal ion complexation on the optical properties was also studied. In search of potential practical application, the complexation of 2-cinnamoyl-1,3-indandiones with metal(II) ions was investigated. A series of non-charged complexes with Cu(II), Cd(II), Zn(II), Co(II) and Ni(II) was isolated and analyzed by elemental analyses and IR. Most of the complexes show presence of water molecules, most probably coordinated to the metal ion, thus forming octahedral geometry. For the paramagnetic Cu(II) complexes a distorted, flattened tetrahedral structure is proposed, basing on the EPR data. The optical properties of the metal complexes, however, do not differ appreciably from those of the free ligands. 相似文献