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91.
Mihaela Badea Rodica Olar Dana Marinescu Gina Vasile 《Journal of Thermal Analysis and Calorimetry》2008,92(1):205-208
This paper reports the investigation of the thermal stability of a series of new complexes with mixed ligands of the type
[M(en)(C3H3O2)2]·nH2O ((1) M=Ni, n=2; (2) M=Cu, n=0; (3) M=Zn, n=2; en=ethylenediamine and (C3H3O2)=acrylate anion). The thermal behaviour steps were investigated in a nitrogen flow. The thermal transformations are complex
processes according to TG and DTA curves including dehydration, ethylenediamine elimination as well as acrylate thermolysis.
The final products of decomposition are the most stable metal oxides except for complex (2) that generates metallic copper. 相似文献
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Morjan Iuliana P. Alexandrescu Rodica Morjan Ion Luculescu Catalin Vasile Eugeniu Osiceanu Petre Scarisoreanu Monica Demian Gabriela 《Journal of nanoparticle research》2013,15(11):1-11
Series of self-assembled and mono-dispersed bovine serum albumin (BSA)-conjugated ZnS/CuS nano-composites with different Zn/Cu ratios had been successfully synthesized by a combination method of the biomimetic synthesis and ion-exchange strategy under the gentle conditions. High-resolution transmission electron microscopy observation, Fourier transform infrared spectra and zeta potential analysis demonstrated that BSA-conjugated ZnS/CuS nano-composites with well dispersity had the hierarchical structure and BSA was a key factor to control the morphology and surface electro-negativity of final products. The real-time monitoring by atomic absorption spectroscopy and powder X-ray diffraction revealed that the Zn/Cu ratio of nano-composites could be controlled by adjusting the ion-exchange time. In addition, the metabolic and morphological assays indicated that the metabolic proliferation and spread of rat pheochromocytoma (PC12) cells could be inhibited by nano-composites, with the high anti-cancer activity at a low concentration (4 ppm). What were more important, Zn and Cu in nano-composites exhibited a positive cooperativity at inhibiting cancer cell functions. The microscope observation and biochemical marker analysis clearly revealed that the nano-composites-included lipid peroxidation and disintegration of membrane led to the death of PC12 cells. Summarily, the present study substantiated the potential of BSA-conjugated ZnS/CuS nano-composites as anti-cancer drug. 相似文献
94.
Zarafu Irina Olar Rodica Chifiriuc Mariana Carmen Bleotu Coralia Ioniţă Petre Mulţescu Mihaela Ioniţă Gabriela Grădişteanu Graţiela Tatibouët Arnaud Badea Mihaela 《Journal of Thermal Analysis and Calorimetry》2018,134(3):1851-1861
Journal of Thermal Analysis and Calorimetry - A series of Schiff bases resulted in the [1?+?1] condensation of 8-alkyl-2-hydroxy-tricyclo[7.3.1.02.7]-tridecan-13-one with the... 相似文献
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Using static oxygen-bomb calorimetry, the standard enthalpies of combustion of the 2,4-and 2,6-isomers of dinitrophenol have been determined as ?2697.22 and ?2723.08 ± 3.18 kJ mole?1, respectively. Standard enthalpies of formation have been calculated as ?235.50 and ?209.64 ± 3.27 kJ mole?1, respectively. 相似文献
99.
We give a precise mathematical formulation of a variational model for the irreversible quasi-static evolution of brittle fractures proposed by G. A. Francfort and J.-J. Marigo, and based on Griffith's theory of crack growth. In the two-dimensional case we prove an existence result for the quasi-static evolution and show that the total energy is an absolutely continuous function of time, although we cannot exclude the possibility that the bulk energy and the surface energy may present some jump discontinuities. This existence result is proved by a time-discretization process, where at each step a global energy minimization is performed, with the constraint that the new crack contains all cracks formed at the previous time steps. This procedure provides an effective way to approximate the continuous time evolution. 相似文献
100.