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41.
Summary A study of the Cd(CN)2 +x X– [Cd(CN)2X
x
]
x–
equilibrium (where X = Cl, Br or CNS) has been carried out at 18° and 38° by measuring the solubility of cadmium cyanide in potassium chloride, bromide and thiocyanate at various concentrations, and at a high ionic strength (6 M) maintained with sodium perchlorate to minimise the effect of activity coefficients. Equilibrium constants forx = 1 and 2 have been calculated and clearly favour the situation wherex = 1. H values for the dissociation of [Cd(CN)2X]– have also been calculated. 相似文献
42.
Study of EPR, optical properties and electrical conductivity of vanadyl doped Bi2O3.PbO.B2O3 glasses
Gahlot PS Agarwal A Seth VP Sanghi S Gupta SK Arora M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(6):1189-1194
Heavy metal based oxide glasses having composition xBi(2)O(3).(0.30 - x)PbO.0.70B(2)O(3) have been prepared (0.00 < or = x < or = 0.15, mol%) containing 2.0mol% of V(2)O(5) by normal melt-quenching technique. Electron paramagnetic resonance (EPR), optical spectra and dc conductivity of these glasses have been studied. Spin Hamiltonian parameters (SHP) of VO(2+) ions, dipolar hyperfine parameter, P and Fermi contact interaction parameter, K, molecular orbital coefficients (alpha(2) and gamma(2)) and optical band gap have been calculated. It is observed that in these glasses, the tetragonal nature of V(4+)O(6) complex increases with Bi(2)O(3) content. Increase in Bi(2)O(3):PbO ratio results in the contraction of 3d(xy) orbit of the unpaired electron in the vanadium ion, and the SHP are dependent on the theoretical optical basicity, Lambda(th). In present glasses, the conductivity (activation energy) first decreases (increases) with increase in mol% of Bi(2)O(3) content upto x = 0.08 and then shows a maxima (minima) at x = 0.10 and then starts decreasing (increasing) upto x < or = 0.15 with mol% of Bi(2)O(3) content. 相似文献
43.
Tricyclopentadienyl cerïum(IV) chloride has been treated with various primary and secondary alcohols in benzene medium in the presence of triethylamine to give compounds, (C5H5)3Ce(OR) wherein R may be CH3 C2H3, n-C2H3, iso-C3H7, N-C4H9, iso-C4H9 and iso-C3H11. Infrared spectra and some physical characteristics of all these compounds and reported. 相似文献
44.
Renu Sharma Santosh K. Agarwal Shikha Rawat Meena Nagar 《Transition Metal Chemistry》2006,31(2):201-206
The synthesis and characterization of some transition metal cis-3,7-dimethyl-2,6-octadiensemicarbazone (CDOSC) complexes are reported. The ligand CDOSC yields: [ML2 Cl2] and [ML2 Cl2] Cl type complexes, where M = CrIII, MnII, FeIII, CoII, NiII, CuII, ZnII, CdII and HgII, L = CDOSC. Structures of the complexes were determined using elemental analysis, molar conductivity, magnetic measurements,
i.r. and electronic, as well as n.m.r spectra. CDOSC acts as a bidentate ligand in all the complexes. All the newly synthesized
metal complexes, as well as the ligand, were screened for their antibacterial activity. All the complexes exhibit strong inhibitory
action against Gram (+) bacteria Staphylococcus aureus and Gram (−) bacteria Escherichia coli. The antibacterial activities of the complexes are stronger than those of the ligand CDOSC itself. 相似文献
45.
A new series of complexes of 5,6-benzoquinoline (Benzqn) with lanthanide perchlorates with the general composition Ln(ClO4)3·7Benzqn (Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy or Ho) were synthesised and characterised by elemental analysis, conductance, molecular weight and infrared spectra. The thermal behaviour of these complexes have also been studied. 相似文献
46.
Summary Methods are described for the micro determination of chlorine, bromine, and iodine in organic compounds containing fluorine. The sample is heated with sodium in a nickel bomb, and the chloride ion produced is determined titrimetrically by a modified procedure involving the use of mercuric oxycyanide. Bromide is determined titrimetrically after oxidation to bromate with sodium hypochlorite; iodide is also determined by an amplified procedure after oxidation to iodate with bromine.The method has been extended to the simultaneous determination of chlorine, bromine, and iodine when present in organic compounds containing fluorine. All four halogens, and all possible combinations of halogens, can be determined in one compound after a single fusion.
Zusammenfassung Es werden Methoden zur Mikrobestimmung von Chlor, Brom und Jod in fluorhaltigen organischen Substanzen beschrieben. Die Probe wird in einer Nickelbombe mit Natrium erhitzt. Das hierbei entstehende Chlorid wird mit Quecksilberoxycyanid nach einem modifizierten Verfahren titriert. Das Bromid wird nach Oxydation zu Bromat mit Natriumhypochlorit titriert. Das Jodid wird mit Brom zu Jodat oxydiert. Nach Zugabe von Jodid wird die sechsfache Jodmenge mit Thiosulfat bestimmt.Das Verfahren wurde für die gleichzeitige Bestimmung von Chlor, Brom und Jod in fluorhaltigen organischen Substanzen erweitert. Alle vier Halogene können somit unabhängig von ihrem gegenseitigen Verhältnis in einer Verbindung nebeneinander ineiner Einwaage bestimmt werden.
Résumé Des méthodes sont décrites pour le microdosage du chlore, du brome, de l'iode dans les composés organiques contenant du fluor. L'échantillon est chauffé avec du sodium dans une bombe de nickel et l'ion chlorhydrique produit est déterminé titrimétriquement par une méthode modifiée mettant en jeu l'emploi d'oxycyanure mercurique. Le brome est dosé volumétriquement après oxydation en bromate a ec l'hypochlorite de sodium. L'iode est déterminé également par une methode amplifiée après oxydation en iodate par le brome.La méthode a été étendue au dosage simultané du chlore, du brome, de l'iode quand ils sont présents dans des composés organiques contenant du fluor. Les 4 halogènes et toutes les combinaisons possibles d'halogènes peuvent être déterminées sur un seul composé après une simple fusion.相似文献
47.
48.
Miss S. Baluja R. N. Singh R. Tripathi B. M. Shukla 《Journal of Radioanalytical and Nuclear Chemistry》1985,94(4):233-239
Tracer diffusion of131I– ions is studied at different temperatures /20°C–50°C/ in 2.5% agar gel containing sodium and potassium sulphate solutions over a wide range of concentrations. The results are in qualitative agreement with the theoretical values in the concentration range 10–6–10–1M. Agar gel shows an obstruction effect to diffusional flow. The activation energy for tracer diffusion was found to be of the order of 16.3 kJ mol–1. 相似文献
49.
50.
Ravinder Agarwal V. R. Singh M. M. Pradhan Ved Singh 《International Journal of Infrared and Millimeter Waves》1991,12(2):115-123
The occurance of the urinary stones varies according to the geographical regions. The presence of stones in the urinary system causes pain and discomfort. These generate colics and hence are sometimes life threatening. In the present study, infrared measurements have been made on several stone samples. It has been found that calcium oxalate, calcium phosphate, magnesiunm ammonium phosphate, calcium carbonate, uric acid, -cystine and xanthin are present, as expected. Also, silicon dioxide is found to be present in some of the stones but in small quantity, in addition to the above constituents. This constituent is responsible to exhibit piezoelectricity in the urinary calculi. 相似文献