Synthesis and characterization of some Cr(III), Fe(III) and Zr(IV) compounds with substituted o-hydroxy benzophenone

Physico-chemical properties of Chitosan films

“…Taking into account the importance of isoconversion methods in thermal analysis [23][24][25], we have performed kinetic calculations using the method proposed by Vyazovkin and co-workers [26,27]. Their method offers kinetic information regarding activation energy and the pre-exponential factor at different degrees of transformation as well as a formal model for the process.…”

Hexakis(urea-O)iron Complex Salts as a Versatile Material Family: Overview of Their Properties and Applications

“…Compounds 2 and 3 are hydrated with 3 mol of water, as determined by vacuum drying over P 2 O 5 . , Zhou et al determined the melting points of compounds 1 and 2 as 136–139 and 178–180 °C, respectively. Russo et al and Foca et al , found much lower melting points for compound 2 , 108 and 95–97 °C, respectively. The melting point differences given by these authors may be attributed to some water content in the sample prepared by Foca et al ( 2CW content in compound 2 ) because 2CW loses its crystal water around the temperature of the given melting point. , Compound 2 is soluble in water and ethanol. , For compounds 3 and 4 , Russo et al determined the melting points, which were found to be 110 and 202 °C, respectively.…”

“…Russo et al and Foca et al , found much lower melting points for compound 2 , 108 and 95–97 °C, respectively. The melting point differences given by these authors may be attributed to some water content in the sample prepared by Foca et al ( 2CW content in compound 2 ) because 2CW loses its crystal water around the temperature of the given melting point. , Compound 2 is soluble in water and ethanol. , For compounds 3 and 4 , Russo et al determined the melting points, which were found to be 110 and 202 °C, respectively. Compounds 1 – 4 were prepared by Carp et al and Russo et al , according to eq .…”

“…11,12 Zhou et al determined the melting points of compounds 1 and 2 as 136− 139 and 178−180 °C, 27 respectively. Russo et al 15 and Foca et al 29,30 found much lower melting points for compound 2, 108 and 95−97 °C, respectively. The melting point differences given by these authors may be attributed to some water content in the sample prepared by Foca et al (2CW content in compound 2) because 2CW loses its crystal water around the temperature of the given melting point.…”

“…Accordingly, the peak of the CO stretching mode gets shifted to a lower wavenumber, while the peak of the C–N mode is moved to a higher wavenumber compared to pure solid urea (Figure . ). ,− Most of the research reports used the ν(CO) and ν(C–N) modes to confirm the formation of hexakis(urea)iron complexes, since these modes have characteristic band positions for the complexes. − ,− In the case of hexakis(urea)iron(II/III) complexes, the ν(CO) symmetric stretching mode is expected between 1580 and 1500 cm –1 in the form of an intense peak (Figure ). ,− The ν(C–N) antisymmetric and symmetric stretching modes are expected between 1500 and 1450 cm –1 and 1050 and 1010 cm –1 , respectively.…”