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Abstract  

Nine rare earth citrate hydrates (RE(C6H5O7nH2O,RE=La, Nd, Sm) were prepared and characterized by chemical analysis, elementary analysis, thermal analysis and IR spectra. The thermal decomposition processes were studied by using TG-DTG and IR spectra techniques. Dehydration enthalpies and dehydration entropies of 3 neodymium and 3 samarium citrate hydrates were also determined by means of DSC.

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Abstract  

The mechanism of Pd(II) and198Au(III) sorption on 4(benzylcellulose)phenylthiocarbamoylamine has been investigated. The data obtained from the sorption dependence on medium acidity and temperature, from isotherms, IR spectra and diffuse reflectance spectra led to the conclusion that the physical sorption of the two elements is accompanied by the formation of chelates. The sorbent might be employed for the concentration of Pd(II) and Au(III) from dilute solutions.

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Abstract  

Using thermogravimetric analyses as well as isothermal gravimetric measurements, the thermal stability of the iron(III) nitrate nanohydrate has been determined. Several decomposition stages are the result of melting, evaporation and hydrolysis processes occurring in the salt—water system in the temperature range of 20–400°C. Some of the intermediates and the final product (-Fe2O3) are characterized by means of chemical analyses, X-ray diffraction patterns and IR spectra.

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Abstract  

A new convenient method has been proposed to synthesize mixed-ligand -diketonato Tc(III) complexes, using the ligand exchange reaction [Tc(acac)2(CH3CN)2]++L [Tc(acac)2L]+ +2CH3CN where L is bza, dpm or dbm. The yield was about 30–40%. UV-visible and IR spectra of these complexes were measured. Characteristic features of the compounds were compared with those of the corresponding complexes of ruthenium.

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Abstract  

We have investigated the influence of the presence of nitric acid on the stability of benzyldibutylamine in the organic phase irradiated by a dose of 143 kGy. The composition of degradation products of radiolysis in individual chromatographic fractions was identified by means of mass, NMR and IR spectra and elemental analysis. It follows from the mass blance that benzyldibutylamine is stable with gamma-radiation of medium-high dose and that its mass loss does not exceed 22% of the irradiated fraction.

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Abstract  

The heterometallic complex [Cu(VO)2(C10H8N2)2(C2O4)3·2H2O] has been prepared and characterised by electronic and IR spectra, molecular electrical conductivity and thermal behaviour. A polymeric structure is proposed with oxalate and 4,4′-dipyridine acting as bridging ligands and VO(IV) of C4v symmetry and Cu(II) in octahedral surrounding the oxalate anion V4h.

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Abstract  

Ampicillin-cobalt complex has been investigated spectrophotometrically. The effects of pH and molar ratio of ampicillin to cobalt were studied. The stability constants for the complex formed at different pH values were determined. Gamma-radiolysis of ampicillincobalt complex in aqueous solutions was studied at doses from 20 to 100 Gy, using a137Cs source. The variations in UV and IR spectra due to their radiolysis were shown. The results showed an increase in absorbance values with increasing dose and this dependence is linear in the dose range studied. The mechanism of radiation effect on the complex is discussed.

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Abstract  

N,N,N′,N′-tetrabutylmalonamide (TBMA) was used for extraction of uranyl(II) ion from nitric acid media into n-dodecane. The effects of nitric acid concentration, extractant concentration, temperature and back extraction on distribution coefficients of uranyl(II) ion have been studied. The extraction of nitric acid is also studied. The main adduct of TBMA and HNO3 is (TBMA)2·HNO3 in 1.0 mol/l nitric acid solution. The 1:2:2 complex of uranyl(II) ion, nitrate ion and TBMA as extracted species is further confirmed by IR spectra of the extraction of uranyl(II) ion with TBMA. The values of thermodynamic parameters have also been calculated.

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Abstract  

N,N,N',N'-Tetrabutyladipicamide (TBAA) was used for the extraction of nitric acid and uranyl(II) ion from nitric acid media into toluene. The effects of nitric acid, uranyl(II) ion, and extractant concentration, temperature and back extraction on the distribution coefficient of uranyl(II) ion have been studied. The main adduct of TBAA and HNO3 is TBAA·HNO3 in 1.0 mol/l nitric acid solution. The 1:2:2 complex of uranyl(II) ion, nitrate ion and TBAA as extracted species is further confirmed by IR spectra of the extraction of uranyl(II) ion with TBAA. The values of the thermodynamic parameters have also been calculated.

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Abstract  

N-dodecanoylpyrrolidine (DOPOD) was synthesized and used for the extraction of nitric acid and uranyl(VI) ions from nitric media in toluene. The effects of nitric acid concentration, extractant concentration, temperature, salting-out agent (LiNO3) have been studied. The main adduct of DOPOD and HNO3 is HNO3·DOPOD. The complex formation of uranyl(VI) ion, nitrate ion and DOPOD (UO2(NO3)2·2DOPOD) as extracted species are further confirmed by IR spectra and the values of thermodynamic parameters have also been calculated.

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