Wyniki wyszukiwania - Biblioteka Nauki

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Crystal and molecular structures of nickel(II) complexes with pyrazine-2,3-dicarboxylic and 3-aminopyrazine-2-carboxylic acids

100%

Ptasiewicz-Bąk H. , Leciejewicz J.

Polish Journal of Chemistry

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1999

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tom vol. 73 nr 4

717-725

EN

Crystals of diaquobis(trans hydrogen pyrazine-2,3-dicarboxylato N,O)niclel(II) - title compound I, contain monometric molecules. The nickel(II) ion is coordinated by two molecules of pyrazine-2,3-dicarboxylic acid, each donating its heteroring nitrogen [Ni-O 2.0485(15) A] and one oxygen atom, belonging to the nearest monodentate carboxylic group [Ni-O 2.0199(14) A]. Two water molecules [Ni-O 2.0914(17) A] complete the octahedral coordination around the central ion. The second carboxylic group and the heteroring nitrogen do not directly bond to the nickel(II) ion. Monometric molecules of the composition Ni(II)(APZA)2(H2))2-title compound II, have been also found in the crystals of diaquobis(trans 3-amino-2-pyrazinecarboxylato O,N)nickel(II) compound. The coordination of the Ni ion is octahedral. (N,O) bonding moieties of two ligand molecules [Ni-O 2.0395(12) A, Ni-N 2.0669(14) A] and the Ni ion are coplanar. The oxygen atoms donated by two water molecules [Ni-O 2.0656(14) A] constitue the vertices of the slightly elongated octahedron. The structures of both title compounds indicate a preference of nickel ion to form monometric molecules. The monometric molecules contain intramolecular hydrogen bonds. The stability of the crystals is maintained by a system of intermolecular hydrogen bonds.

2

The effects of nickel(II) complexes with imidazole derivatives on pyocyanin and pyoverdine production by Pseudomonas aeruginosa strains isolated from cystic fibrosis

88%

Gałczyńska K. , Kurdziel K. , Adamus-Białek W. , Wąsik S. , Szary K. , Drabik M. , Węgierek-Ciuk A. , Lankoff A. , Arabski M.

Acta Biochimica Polonica

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2015

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tom 62

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nr 4

739-745

EN

Pseudomonas aeruginosa infection is problematic in patients with cystic fibrosis (CF). P. aeruginosa secretes a diversity of pigments, such as pyocyanin and pyoverdine. The aim of this study was to evaluate the effects of complexes of nickel(II) ([Ni(iaa)2(H2O)2]·H2O (iaa = imidazole-4-acetate anion), [Ni(1-allim)6](NO3)2 (1-allim = 1-allylimidazole) and NiCl2 on pyocyanin and pyoverdine production by 23 strains of P. aeruginosa isolated from cystic fibrosis under growth conditions specific for the CF respiratory system. The antibacterial effects and biophysical properties of the tested substances were measured by spectrofluorometric techniques, as well as by laser interferometry, confocal and atomic force microscopy. The cytotoxic properties of all compounds were measured by Annexin/IP assay against A549 cells. All tested compounds have no effect on pyocyanin production and decrease the pyoverdine secretion in about 40% of tested P. aeruginosa strains at non-cytotoxic range of concentrations. Imidazole-4-acetate anion and 1-allylimidazole have good diffusion properties in the mature P. aeruginosa PAO1 biofilm. In conclusion, the tested nickel(II) complexes do not have clinical implications in P. aeruginosa eradication in cystic fibrosis. The diffusion properties of 1-allylimidazole and imidazole-4-acetate and their lack of effect on A549 cells suggest that they might be considered for chemical synthesis with other transition metals.

3

Possibility of Some Metals Dissolution in Mixtures of Dimethyl Sulfoxide and Aliphatic Halogen Derivative. Part II. Characteristics of the Metallic Nickel Dissolution Reaction in Binary Organic Mixtures

75%

Lenarcik B. , Jurek K.

Polish Journal of Chemistry

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2005

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tom Vol. 79 / nr 10

1605-1613

EN

Nickel can be dissolved at temperature 323 K in binary organic mixtures containing dimethyl sulfoxide and one of halogeno aliphatic derivatives: 1,2-dibromoethane or tribromomethane, 1,1,2,2-tetrabromoethane, tetrabromomethane and hexachloroethane. As a result of dissolution of metallic nickel in binary organic system the octahedral nickel(II) complexes were obtained. Products of the dissolution of metallic nickel were characterized by UV-Vis and IR spectroscopy,MS spectrometry, thermal decomposition and analytical methods.

4

Comparison of the Phytoavailability of Zinc and Cooper from soil Polluted with Inorganic Nickel and Organic Ni(II) Complexes

51%

Molas J.

Chemia i Inżynieria Ekologiczna

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2003

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tom Vol. 10, nr 9

929-935

EN

In pot experimpnt the influence of nickel in inorganic (sulphate(VI))form and in the form of two organic complexes (Ni(II)-citrate and Ni(II)-EDTA) on the availability, of Cu and Zn by barley plants (Hordeum vulgare L., 'Poldek' cv.) was examined. When nickel was added to acid soil (pH 5.2) in all the three chemical forms and in low concentrations, corresponding to 0 degree of pollution of medium soil, it limited the phytoavailability of Cu and Zn only slightly as compared with the phytoavailability of these elements from soil with natural concentration of the three examined metals. In high concentrations, corresponding to the 2nd and 3rd degree of soil pollution, nickel stimulated the phytoavailability of Cu. The same significant increase of Zn absorption by plants was observed only at the highest Ni content in the soil. Nickel complexed by citric acid and EDTA stimulated the phytoavailability of Cu arid Zn more than its inorganic form. From among the two nickel complexes used in the experiment, in the Ni(II)-EDTA form nickel stimulated the availability of Cu and Zn (particularly that of Cu) by barley plants more than the Ni(II)-citrate form.

PL

W doświadczeniu wazonowym badano wpływ niklu w formie nieorganicznej (siarczanowej(VI)) oraz w formie dwóch kompleksów organicznych (Ni(II)-cytrynian i Ni(II)-EDTA) na przyswajanie Cu i Zn przez rośliny jęczmienia jarego (Hordeum vulgare L.) odmiany 'Poldek'. Nikiel we wszystkich trzech formach chemicznych i w małym stężeniu, odpowiadającym 0° zanieczyszczenia gleby średniej, dodany do gleby kwaśnej (pH 5,2) o składzie granulometrycznym pyłu zwykłego, nieznacznie ograniczał fitoprzyswajalność Cu i Zn w stosunku do fitoprzyswajalności tych pierwiastków z gleby o naturalnej zawartości wszystkich trzech badanych metali. W większych koncentracjach, odpowiadających 11° i III° zanieczyszczenia gleby, nikiel stymulował fitoprzyswajalność Cu. Podobnie istotne zwiększenie absorpcji Zn przez rośliny zanotowano tylko w przypadku największej zawartości Ni w glebie, odpowiadającej III° zanieczyszczenia gleby. Nikiel zastosowany w formie kompleksów organicznych stymulował w większym stopniu fitoprzyswajalność Cu i Zn niż jego forma nieorganiczna. Spośród dwóch zastosowanych w badaniach kompleksów niklu, nikiel w formie Ni(II)-EDTA w większym stopniu stymulował pobieranie Cu i Zn (szczególnie Cu) przez rośliny jęczmienia niż w formie kompleksu z kwasem cytrynowym.