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Journal of Thermal Analysis and Calorimetry
Authors: Yu. Trach, V. Sydorchuk, O. Makota, S. Khalameida, R. Leboda, J. Skubiszewska-Zięba, and V. Zazhigalov

not detected by means of used methods of investigations. The increase of specific surface area of milled samples (C3, C4) confirms the latter suggestion. UV–Vis spectroscopy study It is well known that the results

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Journal of Thermal Analysis and Calorimetry
Authors: V. Sydorchuk, O. Makota, S. Khalameida, L. Bulgakova, J. Skubiszewska-Zięba, R. Leboda, and V. Zazhigalov

spectroscopy More detailed information about structure of deposited phases was obtained with the help UV–Vis spectroscopy that get a deeper insight on the state of the vanadia and molybdena at support surface [ 19 ]. It is known that UV–Vis absorption

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Journal of Thermal Analysis and Calorimetry
Authors: P. S. Epaminondas, K. L. G. V. Araújo, J. A. Nascimento, M. C. D. Silva, R. Rosenhaim, L. E. B. Soledade, N. Queiroz, A. L. Souza, I. M. G. Santos, and A. G. Souza

function of the overall peak area. The physico-chemical properties were measured according to the methods described by AOCS [ 8 ]. The oil samples were also characterized by UV–Vis spectroscopy using a Shimadzu UV-2550 spectrophotometer at the 200

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Journal of Thermal Analysis and Calorimetry
Authors: J. Maul, A. S. Brito, A. L. M. de Oliveira, S. J. G. Lima, M. A. M. A. Maurera, D. Keyson, A. G. Souza, and I. M. G. Santos

to form Cu 2 O at around 1039–1043 °C. Wang et al. [ 8 ] reported the same synthesis using copper acetate in ethanolic solution with NaOH and showed by using UV–Vis spectroscopy that absorption peak of CuO is located at about 340 nm and no presenting

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Reaction Kinetics, Mechanisms and Catalysis
Authors: Mohammad Saleh Ghodrati, Mohammad Haghighi, Jafar Sadegh Soltan Mohamdzadeh, Behzad Pourabas, and Ehsan Pipelzadeh

media at 25 °C. Samples were taken at 15 min intervals from the reaction media and filtered using a 0.45 μm filter to form a clear solution. Further investigation of photocatalytic performance was conducted using a Philips UV–vis spectroscopy, indicating

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Journal of Thermal Analysis and Calorimetry
Authors: F. T. G. Vieira, A. L. M. Oliveira, D. S. Melo, S. J. G. Lima, E. Longo, A. S. Maia, A. G. Souza, and I. M. G. Santos

are difficult to eliminate after formation. Elimination of the organic material was evaluated by thermal analysis (TG/DTA) and infrared spectroscopy. X-ray diffraction was used to evaluate the crystallization, while UV–vis spectroscopy permitted to

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radiation wavelength, k = 0.90 and 2θ is the Bragg angle [ 14 ]. UV–Vis spectroscopy was also utilized to measure the optical transmittance of the produced films using a Varian Cary 500 Scan spectrophotometer. To evaluate the catalytic activity

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DTA curves ( a ) TiO 2 , ( b ) CdSe, ( c ) TiO 2 + CdSe, ( d ) TiO 2 + CdSe + linker UV–Vis spectroscopy Figure 5 shows the normalized UV–Vis absorption of TiO 2

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Journal of Thermal Analysis and Calorimetry
Authors: D. Melo, R. M. M. Marinho, F. T. G. Vieira, S. J. G. Lima, E. Longo, A. G. Souza, A. S. Maia, and I. M. G. Santos

and could be confirmed by UV vis spectroscopy that showed higher amounts of Cu(I) for samples with higher copper amount and higher heat treatment temperatures. The authors acknowledge Coordination of Improvement of Higher

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Journal of Thermal Analysis and Calorimetry
Authors: Y. Y. Di, Z. C. Tan, L. W. Li, S. L. Gao, and L. X. Sun

Abstract

Low-temperature heat capacities of a solid complex Zn(Val)SO4·H2O(s) were measured by a precision automated adiabatic calorimeter over the temperature range between 78 and 373 K. The initial dehydration temperature of the coordination compound was determined to be, T D=327.05 K, by analysis of the heat-capacity curve. The experimental values of molar heat capacities were fitted to a polynomial equation of heat capacities (C p,m) with the reduced temperatures (x), [x=f (T)], by least square method. The polynomial fitted values of the molar heat capacities and fundamental thermodynamic functions of the complex relative to the standard reference temperature 298.15 K were given with the interval of 5 K.

Enthalpies of dissolution of the [ZnSO4·7H2O(s)+Val(s)] (Δsol H m,l 0) and the Zn(Val)SO4·H2O(s) (Δsol H m,2 0) in 100.00 mL of 2 mol dm−3 HCl(aq) at T=298.15 K were determined to be, Δsol H m,l 0=(94.588±0.025) kJ mol−1 and Δsol H m,2 0=–(46.118±0.055) kJ mol−1, by means of a homemade isoperibol solution–reaction calorimeter. The standard molar enthalpy of formation of the compound was determined as: Δf H m 0 (Zn(Val)SO4·H2O(s), 298.15 K)=–(1850.97±1.92) kJ mol−1, from the enthalpies of dissolution and other auxiliary thermodynamic data through a Hess thermochemical cycle. Furthermore, the reliability of the Hess thermochemical cycle was verified by comparing UV/Vis spectra and the refractive indexes of solution A (from dissolution of the [ZnSO4·7H2O(s)+Val(s)] mixture in 2 mol dm−3 hydrochloric acid) and solution A’ (from dissolution of the complex Zn(Val)SO4·H2O(s) in 2 mol dm−3 hydrochloric acid).

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