Wyniki wyszukiwania - BazTech

1

Badania potencjometryczne, ESI-MS i NMR nad kompleksowaniem magnezu(II) i wapnia(II) wybranymi kwasami bisfosfonowymi w roztworze wodnym

Szpak M., Matczak-Jon E., Kurzak B.

Chemik

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2014

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Vol. 68, nr 4

321--328

PL

Przeprowadzono badania nad równowagami w roztworze układów Mg(II)/Ca(II)-L (L= kwas (cykloheksylo)aminometano-1,1-difosfonowy (1), kwas azepan-1-ylo-metano-1,1-difosfonowy (2), kwas azekan-1-ylo-metano-1,1-difosfonowy (3)) metodami pH-potencjometrii, NMR i ESI-MS. Uzyskane wyniki wskazują, że we wszystkich badanych układach preferowane jest tworzenie kompleksów jednordzeniowych o stechiometrii 1:1. Rozpatrywane związki wiążą koordynacyjnie Mg(II) i Ca(II) poprzez atomy tlenu grup fosfonianowych w szerokim zakresie wartości pH.

EN

Solution equilibrium studies on the Mg(II)/Ca(II)-L systems (L= (cyclohexyl)aminomethane-1,1-diphosphonic acid (1), azepan-1-yl-methane-1,1-diphosphonic acid (2), azecan-1-yl-methane-1,1-diphosphonic acid (3) have been performed by pH-potentiometry, NMR and ESI-MS methods. The obtained results suggest preference for the formation of mononuclear complexes of 1:1 stoichiometry in all studied systems. Compounds under consideration coordinate Mg(II) and Ca(II) through oxygen atoms of the phosphonate groups over a broad pH range.

2

Complexes of 2-mercaptopyrimidines with metals in sodium azide solution : investigation of composition and reactivity by iodine-azide reaction

Janowicz K., Kurzawa J.

Chemia Analityczna

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2008

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Vol. 53, No. 1

71-81

EN

The iodine-azide reaction selectively induced by sulfur(II) compounds has been used for the investigation of metai complexes with 2-mercaptopyrimidine and its ten homologues. Substitution of mercaptopirymidines ligands with azide ions at a milimolar level has been investigated. The studied complexes were arranged in the inertness series. The time of complex formation and their composition have been established.

PL

Reakcję jodo-azydkową indukowaną selektywnie przez związki siarki dwuwartościowej zastosowano do badania kompleksów metali z 2-merkaptopirymidyną i jej dziesięcioma homologami. Reakcję wymiany ligandów merkaptopirymidynowych na jony azydkowe badano na poziomie milimoli, podano szeregi bierności kompleksów oraz skład i czas ich tworzenia.

3

Spectrophotometric determination of lisinopril in commercial dosage forms using N-bromosuccinimide and chloranil

Rahman N., Siddiqui M. R., Azmi S. N. H.

Chemia Analityczna

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2007

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Vol. 52, No. 3

465-480

EN

Two simple, fast, sensitive, and economical spectrophotometric methods for quantification of lisinopril in drug formulations have been developed. Method A was based on the reaction between primary amino group of the drug with N-bromosuccinimide in acetone medium giving a yellow-colored product of maximum absorption at 353 nm. Method B was based on the formation of purple-colored charge transfer complex between the drug and chloranil in 1,4-dioxan-acetonitriIe medium. Beer's law was obeyed in the concentration ranges of 10-200 and 24-600 μg mLTwo simple, fast, sensitive, and economical spectrophotometric methods for quantification of lisinopril in drug formulations have been developed. Method A was based on the reaction between primary amino group of the drug with N-bromosuccinimide in acetone medium giving a yellow-colored product of maximum absorption at 353 nm. Method B was based on the formation of purple-colored charge transfer complex between the drug and chloranil in 1,4-dioxan-acetonitriIe medium. Beer's law was obeyed in the concentration ranges of 10-200 and 24-600 ug mL'1 with molar absorptivities of 1.40 x 103 and 7.28 x 102 L-1 mol cm'1 for methods A and B, respectively. Regression analysis yielded the following calibration equations: A = -2.44 x 10-1 + 3.16 x 10-1 C and A = 5.39 x 10-4+ 1.65 x 10-3C for methods A and B, respectively. For both calibration equations correlation coefficients were 0.9999. Intra- and inter-day precisions were lower than 1.60%. The optimum experimental conditions for the proposed methods have been investigated. Methods A and B have been successfully applied to the analysis of lisinopril in drug formulations. The results have been statistically compared to these obtained applying the British pharmacopoeia method with molar absorptivities of 1.40 x 103 and 7.28 x 102 L-1 mol cm-1 for methods A and B, respectively. Regression analysis yielded the following calibration equations: A = -2.44 x 10-1 + 3.16 x 10-1 C and A = 5.39 x 10-4+ 1.65 x 10-3C for methods A and B, respectively. For both calibration equations correlation coefficients were 0.9999. Intra- and inter-day precisions were lower than 1.60%. The optimum experimental conditions for the proposed methods have been investigated. Methods A and B have been successfully applied to the analysis of lisinopril in drug formulations. The results have been statistically compared to these obtained applying the British pharmacopoeia method

PL

Opracowano dwie proste, szybkie, czule i ekonomiczne spektrofotometryczne metody ilościowego oznaczania lizynoprilu w preparatach farmaceutycznych. Metoda A jest oparta na reakcji picrwszorzędowej grupy aminowej leku z N-bromosukcynimidem w acetonie, w wyniku której powstaje żółty produkt wykazujący maksimum absorpcji przy df. fali 353 nm. Metoda B polega na tworzeniu purpurowego kompleksu z przeniesieniem iadunku miedzy lekiem a chloranilem w mieszaninie 1,4-dioksanu i acetonu. Prawo Beer'a było . spełnione w zakresie stężeń 10-200 i 24-600 1.40 x 103; absorpcja molowa wynosiła 1.40 x 103 and 7.28 x 102 L-1 mol cm-1, odpowiednio w przypadku metody A i B, W wyniku analizy regresji otrzymano dwa równania kalibracyjne A =-2,44 x 10-4 + 3,16 x 10-3 C oraz A = 5,39 x10-4 + 1,65 x 10-3 C, odpowiednio dla metody A i B. Obie metody zoptymalizowano i zastosowano z powodzeniem do analizy lizynoprilu w preparatach farmaceutycznych. Otrzymane wyniki porównano z wynikami uzyskanymi według Farmakopei Brytyjskiej.

4

Thermal decomposition of Sn(II), Pb(II), Cd(II) and Hg(II) cross-linked metal-alginate complexes

El-Gahami M. A., Khairou K. S., Hassan R. M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 2

105-113

EN

The thermal decomposition of tin(II), lead(II), cadmium(II) and mercury(II) metal-alginate complexes has been studied using thermogravimetry (TG) and differential thermogravimetry (DTG) measurements. The TG curves showed three stages of weight loss, the DTG curves indicated the presence of a series of thermal stages associated with the TG curves. Dehydration of the coordinated water molecules occurred in the first stage, followed by decomposition of the dehydrated complexes in the next two stages. Thermal stability of these complexes in terms of the strength of chelation and coordination geometry is discussed.

5

Synthesis and spectroscopic characterization of new tin(II) complexes containing nitrogen and oxygen donor ligands

Singh H. L., Gupta M. K., Varshney S., Varshney A. K.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 1

5-14

EN

Some new tin(II) complexes have been synthesized by the reactions of tin(II) methoxide with nitrogen donor ligands. The ligands used in these studies are condensation products of heterocyclic aldehydes/ketones and sulpha drugs. Their structures have been confirmed on the basis of elemental analyses, ultraviolet, infrared and multinuclear magnetic resonance (1H, (13)C and (119)Sn) spectral studies. The bivalent nature and their square pyramidal geometry around tin(II) have been deduced on the basis of 119Sn Mossbauer spectral data. Monomeric and non-electrolytic nature of these complexes have been confirmed by molecular weight determinations and conductance measurements.

6

Determination of sulfite by ion pair chromatography using pre-column derivatization with iron(III)-1,10-phenanthroline complex

Janovskiene G., Paliulionyte V., Padarauskas A.

Chemia Analityczna

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2002

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Vol. 47, No. 6

847-854

EN

An ion-pair chromatographic (IP-HPLC) method was developed for the selective and sensitive determination of sulfite. The proposed method is based on the pre-column derivatiza-tion of sulfite with iron(III)-l,10-phenathroline complex (Fe(phen)(3+/(3) and direct photometric detection of Fe(phen)(2+)(3) formed. The optimized separations were carried out on a C(18) column using acetonitrile-water (60:40) mobile phase containing 50 mmol L(-1) NaClO4 and 5 mmol L(-1) acetate buffer (pH 5.0) and direct photometric detection at 510 nm. The optimal conditions for the derivatization reaction were established by varying pH, concentration of Fe(phen)(3+)/3 and reaction temperature. Valid calibration (r2 = 0.998) is demonstrated in the range 2 x 10(-6)-5 x 10(-4) mol L(-4) of sulfite. The detection limit (S/N = 3) was 5 x 10(-7) mol L(-1). The proposed system was applied to the determination of free sulfite in wines. The recovery tests established for wine samples were within the range 94-105%. The IP-HPLC results agree with those obtained by iodometric titration technique.

PL

Opracowano selektywną i czułą metodę oznaczania siarczynów przy pomocy chromatografii par jonowych (IP-HPLC). Proponowana metoda jest oparta na przedkolumnowej derywaty-zacji siarczynu przy użyciu kompleksu żelazo(III)-1, 10-fenantrolina Fe(phen)(+3/3 Utworzony jon Fe(phen)j+jest bezpośrednio mierzony fotometrycznie przy długości fali 510 nm. Optymalizację rozdziału przeprowadzono na kolumnie C(18) z fazą ruchomą acetonitryl-woda (60:40) z dodatkiem 50 mmol L(-1) NaClO(4) i 5 mmol L(-1) buforu octanowgo (pH 5,0). Optymalne warunki reakcji derywatyzacji ustalano zmieniając wartości pH, stężenie Fe(phen)(+3)/(3) oraz temperaturę. Liniową zależność kalibracyjną (r2 = 0,998) uzyskano w zakresie stężeń 2 x 10(-6) -5 x 10(-4) mol L(-1) siarczynów. Granica wykrywalności (S/N = 3).

7

Hydrogen bonded complexes of coumarin 153

Królicki R., Jarzęba W., Soroushian B., Lampre I., Mostafavi M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 4

435-449

EN

Detailed studies of the hydrogen-bonded complexes of coumarin 153 (C153) have been carried out. It has been shown that nonlinear shifts of the steady-state absorption and fluorescence spectra taken in toluene-methanol solvent mixtures are caused by the formation of hydrogen bonded complexes between C153 and methanol, while preferential solvation plays a minor role only. IR measurements confirmed the ability of C153 to form hydrogen-bonded complexes with methanol and phenol. The stoichiometry of the formed complexes and relevant equilibrium constants have been estimated. Femtosecond solvation dynamics measurements of C153 in the toluene-methanol mixture (xMeOH = 0.2) showed that the average solvation time is higher than that in the pure solvents indicating slower relaxation of methanol in the mixture. The slow component of solvation dynamics (ok 20ps) can be attributed to translational diffusion of methanol to the first solvation shell of C153 and to the relatively slow reorientational motion of methanol involved in formation of hydrogen bond with the excited C153.

8

Dithiocarbonate and trithiocarbonate complexes derived from VV, MoVI, ReVII tetraoxothioprecursors

Dessapt R., Simonnet-Jegat C., Secheresse F.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 1

15-25

EN

Reactions of MoS(2)/(4), MoO(2)S(2)(2-), MoO(2)(4), ReSJ, ReO-(4), VS(3)/(4), and VO(3-)(4) with CS(2) are described. The syntheses and X-ray determinations of (NEt(4))(2) [Mo2(S)(2) (Mo(2) S)(2) (u -S)(2)], space group P2(1)/C, a = 9.3169(3) A,b = 16.3211(5) A, c = 22.8415(5) A, Beta = 92.590(1)°, V = 3469.8(2) A3, R = 0.0898 for 8720 independent reflections and (NEt(4))(2)[Mo(2)(O)(2)(Mi - S)(mi - O)(n(2) - COS(2)2] 0.5 CS(2), space group P2(1)/C, a = 9.8190(1) A, b = 20.6313(13) A, c = 15.7193(3) A, Beta = 92.353(1)°, V = 3181.71(8) A(3), R = 0.0576 for 5760 independent reflections are presented. A rationalization of the syntheses is discussed and the structure of (NH4)[HCOS(2) is described, space group Pca2i, a = 8.3174(9) A, b = 5.6562(6) A, c = 10.7125(12) A, V = 503.97(9) A3, R = 0.0402 for 952 independent reflections. (13)C NMR data for trithiocarbonate and dithiocarbonate complexes are presented.

9

Coordination chemistry of Mo(IV) and W(IV) based on tetracyanodioxo precursors

Samotus A., Szklarzewicz J., Matoga D.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 2

145-164

EN

The substitution reactions of [M(CN)(4)O(H(2)O)](2-) (M = Mo, W) used as starting material are described. The chemistry of complexes of the type [M(CN)4O(L)](n-), [M(CN)(3)O(LL)](n-) and [Mo(CN)(2)O(LLLL)] is discussed, basing on their structures and spectroscopic properties.

10

Studies of the equlibria of complexes of Pr(III), Nd(III), Eu(III), Gd(III), Dy(III) and Er(III) with quercetin-5'-sulfonic acid in aqueous solutions

Kopacz M., Bujonek B., Nowak D., Kopacz S.

Chemia Analityczna

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2001

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Vol. 46, No. 5

621-631

EN

The equilibria of the dissociation reaction of QSA as well as those of the complexation of QSA with Pr(III), Nd(III), Eu(lII), Gd(IlI), Dy(III) and Er(III) in aqueous solutions were investigated. The composition and formation constants of the complexes were determined by the spectrophotometric and potentiometric methods. The spcctrophoto-metric method was suggested to determine the above lanthanides with QSA.

PL

Zbadano równowagi reakcji dysocjacji kwasu kwercctyno-5'-sulfonowego (QSA) oraz reakcji komplcksowania QSA z jonami Pr(III),Nd(III), Eu(lII), Gd(III), Dy(III) i Er(III) . w roztworach wodnych. Skład i stale tworzenia kompleksów wyznaczono metodą spek-trofotometryczną i metodą potcncjometryczną. Zaproponowano metodą speklrofoto-metryczną do oznaczania wyżej wymienionych jonów lantanowców za pomocą QSA.

11

Derivative spectrophotometric methods for the determination of rhodium, palladium and platinum in mixtures

Balcerzak M., Bystrońska D., Święcicka E.

Chemia Analityczna

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2001

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Vol. 46, No. 4

547-560

EN

Derivative spectrophotometric methods allowing direct determination of rhodium, palladium and platinum in binary mixtures have been developed. The complexes of the metals with tin(II) chloride make the basis of spectrophotometric measurement. The determination of the metals can be carried out in aqueous solutions or after extraction into 1,2-dichloroethane in the form of the ion-associates Rh(Pd, Pt)-SnCl(3)-diantipirylme-thane (DAM). Palladium and platinum in spent autocatalyst have been determined by the developed methods.

PL

Opracowano bezpośrednie metody oznaczania rodu, palladu i platyny w podwójnych mieszaninach z wykorzystaniem techniki spektrofotometrii pochodnej. Kompleksy metali z chlorkiem cyny(II) stanowiły podstawę spektrofotometrycznego pomiaru. Metale można oznaczać w roztworze wodnym lub po ekstrakcji 1,2-dichloroetanem w postaci asocjatów jonowych Rh(Pd,Pt)-SnCl(3)-diantypirylometan (DAM). Opracowane metody zastosowano do oznaczania palladu i platyny w zużytym katalizatorze samochodowym.

12

Structural and vibrational studies of the molecular crystal formed by benzenamine with trifluoroacetic acid

Baran J., Barnes A. J., Barycki J., Pietraszko A., Ratajczak H.

Bulletin of the Polish Academy of Sciences. Chemistry

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2001

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Vol. 49, No. 2

115-124

EN

The crystal structure of benzenamine-trifluoroacetic acid has been found to belong to the P2i space group of the monoclinic system, with Z = 8, o = 10.294(2) A, b = 9.126(2) A, c = 20.603(4) A, and Beta = 98.77(3)°. In the crystal the amine is protonated and the resulting benzenammonium and trifluoroacetate ions are interlinked by a network of N—H- • -O hydrogen bonds. The observed infrared spectrum is in accordance with such a structure.

13

Influence of anions on the reversible Ru3O2(NH3)147+ - Fe(II) electron transfer system

Banaś B., Nahorska M., Mroziński J.

Bulletin of the Polish Academy of Sciences. Chemistry

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2001

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Vol. 49, No. 3

203-211

EN

The influence of perchlorate, chloride and sulphate ions on the reversible electron transfer redox system formula was examined in the acidic solution by the stopped-flow spectrophotometry. The positive salt effect, typical of reactions between similarly charged ions, and an unusually strong accelerating effect of chloride and sulphate ions on the reactions rates were observed. The latter could be explained in terms of complex formation between the iron ions and the anions investigated with the resultant complexes reacting faster than respective iron-aqua complexes.

14

Electrochemical studies of trans-dichloro-bis(diphenylphosphino) methane rhenium complex

Rabia M. K. M.

Bulletin of the Polish Academy of Sciences. Chemistry

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2001

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Vol. 49, No. 4

265-277

EN

Electrochemical studies of the fraras-dichloro-bis (diphenylphosphino) methane rhenium in tetrabutylammonium perchlorate/dichloromethane have been performed using cyclic and convolution potential sweep voltammetry. At room temperature, it was found that the complex isomerises on oxidation from the irons- to the cis-isomer and returns back to the original complex form on reduction at lower potentials. The electrode mechanisms were proposed and discussed on the basis of the "square-scheme". Upon cooling to 233 K, the cyclic voltammetric behaviour shows a single reversible couple in the region expected for the oxidation of trans-[ReC\2 (dppm)2]. Furthermore, the homogeneous and heterogeneous rate constants of the isomerisation reaction were evaluated.

15

Vibronic behaviour of octahedral Cu(II) complexes in Cu(2-benzoylpyridine)2(NO3)2x2H2O crystal with a weak superexchange coupling. Temperature EPR studies

Hoffmann S. K., Goslar J., Hilczer W., Goher M. A. S.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 4

397-409

EN

Octahedral [Cu(2-benzoylpyridine)2 (H20)2] complexes in the Cu(2-Bzpy)2-(NO3)2 .2H2O are very dynamical and Cu(II) ions are very weakly coupled as it is shown by the single crystal EPR measurements in the temperature range 4.2-300 K. Rigid lattice limit (9 K) of spin-Hamiltonian parameters are: gx = 2.137, gy = 2.014, gz = 2.306 as determined by decoupling of exchange merged EPR lines. The ground state is predominantly Ix(2) -y(2)) with 8% of the Iz(2)) state. This mixing is produced by zero-point motions in the ground vibrational state and results in g x > gy with strong lowering of the gy-value. The decoupling procedure gave superexchange coupling parameter J = 0.0040 cm(1), which unexpectedly is temperature independent in contrast to other weakly coupled Cu(II) paramagnets. The g-factors show relatively strong temperature variations with gy practically not affected by temperature and a tendency to averaging of the g x and gz with room tem-perature parameters: g x = 2.161, gy = 2.013, gz = 2.285. This is explained as the pseudo Jahn-1eller effect with dynamical transitions between two elongated octahedral axes, i.e. O-Cu-O (x-axis) and H2O-Cu-H2O (z-axis) with N-Cu-N (y-axis) direction ill the in-plane coordination with pyridine nitrogen not affected by vibronic dynamics. The vibronic effect can be described by two-well model in the temperature range 80-150 K only with energy difference between the ground vibronic state in the well being 220 cm-l. At lower temperatures Cu(II) complexes are strongly localized in the deepest potential well, whereas at higher temperatures, the vibronic g-factor averaging is dominated by the other mechanism.

16

Synthesis and spectroscopic studies of tin(IV) complexes of biologically active Schiff bases of sulpha drugs and heterocyclic aldehydes/ketones

Gupta M. K., Singh H. L., Tripaathi U. D., Varshney A. K.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 3

195-201

17

Synthesis and characterization of some new tin(IV) complexes with macrocyclic schiff bases

Singh H. L., Varshney A. K.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 2

125-130

EN

Some new tin (IV) complexes with macrocyclic Schiff bases, viz. 1,5,9,13-tetraaza-2,10-dimethyl-4,12-diphenyl cyclohexadeca-l,4,9,12-tetraene (L1) and 1,4,8,12-tetraaza-6,9,13,14-dibenzocyclotetradeca-l,4,8,11-tetraene (L2 ) have been synthesized. An attempt has been made to probe their structures on the basis of elemental analyses, molec-ular weight determination, electronic, infrared, 1H NMR and (119)Sn NMR spectroscopy. Molar conductance has shown the non-electrolytic behaviour of the tetravalent metal complexes that appear to be 1 : 1 electrolytes. Six-coordinate structure has been proposed for all tin complexes.

18

Isomerization of vegetable oils catalyzed by ruthenium complexes

Krompiec S., Suwiński J., Majewski J., Grobelny J.

Polish Journal of Applied Chemistry

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1998

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Vol. 42, nr 1

43-48

EN

A study on isomerization of industrial oils - rapeseed, soybean, suntlower and linseed - was performed in the presence of the following ruthenium complexes: [RuHCl (CO)(PPh(3), [Ru(CO)3(PPh(3)2], [Ru(C2(1,5-COD)]x [Ru(acac)3], [RuCl2(PPh3)3)3], (RuH2(PPh3)]4], [RuCl2(AsPh3]3], [RuCl2(NBD)]x and [RuCl2(SbPh3)3]. The reactions were carried out in bulk under air atmosphere at 212st.C and 226st.C. Concentration of the complexes corresponded to 58 or 116 ppm of ruthenium. The best results were obtained with [RuHCl(CO)(PPh3)3 as the catalyst. Separation of the catalyst from isomerized oils was accomplished by sorption on diatomaceous earth or on active carbon. The isomerized rapeseed, soybean, sunllower and linseed oils were found to contain respectively 30, 54, 54 and 50 wt-% of conjugated isomers, up to 10 wt-% of polymeric materials and less than 1 ppm of ruthenium.

19

Zależność między składem ekstrograficznym paków a ich zdolnością do kompleksowania z jodem

Kaczmarska H., Więcek I., Machnikowski J.

Karbo

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1998

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Nr 8

265-269

PL

Przedstawiono wyniki frakcjonowania metodą ekstrografii paku węglowego i naftowego. Uzyskane informacje natury chemicznej odniesiono do wyników rozdziału tych paków metodą kompleksowania z przeniesieniem ładunku (CTF) . Opisano zależność miedzy składem ekstrograficznym paków a wydajnością i właściwościami frakcji o różnej reaktywności chemicznej, uzyskanymi w wyniku ich rozdziału metodą kompleksowania jodem.

EN

Results of fractionation by using of extrographic method for coal-tar and petroleum pitches were presented. A received information was compared to data resulting ˇfrom a separation of pitches by the complexing method with charge transfer (CTF). A correlation between an extrographic composition of pitches, yield and properties of fractions of different chemical reactivity obtained from their separation by the complexing method with iodine, was described.

20

Potentiometric and spectrophotometric measurements of stability constants of complexes in non-aqueous solutions

Gorodkiewicz E., Figaszewski Z.

Chemia Analityczna

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1998

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Vol. 43, No. 3

445-455

EN

The complex formation equlibria are responsible for e.g. selectivity and sensitivity of ion-selective electrodes with liquids membranes. In this work, it is attempted to take advantage of potential variations in the potentiometric measurements of the complexes as well as the changes in absorbance in the kinetic spectrophotometric measurements caused by their photodissociation to study the equilibria in which they are involved. The Ni(II) complexes with o,cí -didecyldithiophosphoric acid soclium salt and Cu(II) complexes with salicylaniline in 1,2-dichloroethane (DCE) and in 1,1,2,2-tetrachloroethane TCE) were chosen for the study. The dependences of the potential and of the absorbance on the solvent as well as on the concentration were studied in the range: 1.2-40 mmol 1(-1) for the Ni(II) complex in DCE; 0.8-12 mmol 1(-1) in TCE and 0.4-4 mmol l(-1) for the Cu(II) complex in DCE and 0.2-4 mmol l(-1) TCE. Emf was found to depend linearily on radiation intensity and the effect of temperature on the ernf variations was found to be slight. The stability constants of the studied complexes were determined directly from the spectrophotometric measurements; they were logßay = 10.21 in DCE, and logß; and log ß av=8.1 in TCE for the Ni(II) complexes, and logßav = 7.91 in DCE and logßav=10.79 in TCE for the Cu(II) complex.

PL

Równowagi kompleksowania są odpowiedzialne m.in za selektywność i czułość elektrod jonoselektywnych zawierających ciekłe membrany. Praca stanowi próbę wykorzystania zmian potencjałów (pomiary potencjometryczne), oraz zmian absorbancji (kinetyczne pomiary spektrofotometryczne), wywołanych fotodysocjacją kompleksów, do badań równowag, w których one uczestniczą. Do badań wybrano kompleksy Ni(II) z solą sodową kwasu o,ó -didecyloditiofosforowego, oraz Cu(II) z salicyloaniliną w 1,2-dichloroetanie (DCE) i 1,1;2,2-tetrachloroetanie (TCE). Zbadano zależność zmian potencjałów oraz absorbancji od rodzaju rozpuszczalnika oraz od stężenia, w zakresie: 1.2(-1) mmol 1(-1) dla kompleksu Ni(II) w DCE i 0.8-12 mmol 1(-1) w TCE, oraz 0.4 mmol 1(-1) dla kompleksu Cu(II) w DCE i 0.2-4 mmol 1(-1) w TCE. Stwierdzono liniową zależność zmian SEM od natężenia promieniowania oraz minimalny wpływ temperatury na otrzymywane zmiany SEM. Z pomiarów spektrofotometrycznych bezpośrednio określono wartości stałych trwałości badanych kompleksów, które wynoszą dla kompleksu Ni(II) w DCE logßśr =10.21 i w TCE, logßśr = 8.1, a dla kompleksu Cu(II) w DCE logßśr = 7.91 i w TCE logßśr =10:79.