ABSTRACT
Composite materials made of cellulose fibers and spin crossover micro-particles were investigated by magnetic measurements and dynamic mechanical analysis (DMA). The storage modulus of the cellulose handsheet (0.6 GPa at room T) is significantly enhanced in the composite (1.7 GPa). The latter also displays a reversible increase of ca. 10% when switching the magnetic spin state of the particles from the low spin (LS) to the high spin (HS) form. Around the spin transition temperature a loss modulus peak is also observed, highlighting the strong viscoelastic coupling between the particles and the cellulose matrix. These results pave the way for the development of a novel family of actuator materials based on spin crossover-polymer composites.
ABSTRACT
[Fe(Htrz)2(trz)]BF4@SiO2 nanorods were synthesized using a reverse emulsion technique and a Tb(3+) complex was chemically bound to the silica surface. This Tb-spin crossover nanocomposite demonstrates high luminescence stability under continuous thermal cycling. A reabsorption mechanism is determined to be responsible for the luminescence intensity variation during the spin state switching of the iron complex.
ABSTRACT
The purpose of the study was to develop diagnostic and prognostic criteria for the development of urolithiasis (UL), by using the chromatographic mass spectrometric and aggregatometric techniques, in order to determine the type of a metabolic disturbance and the type of stone formation, as well as to create an algorithm of pathogenetically grounded prevention of the disease. According to the type of a metabolic disorder, all the patients were divided into 4 groups: (1) 47 (43.1%) patients with uric acid UL; (2) 26 (23.9%) with calcium oxalate UL; (3) 25 (22.9%) with calcium phosphate UL; (4) 11 (10.1%) with mixed UL. The specific feature of Group 4 was a preponderance of patients with calcium phosphate and calcium oxalate stones. Analysis of the findings has led to the conclusion that the new guidelines for the diagnosis and pathogenesis of UL, by applying the current chromatographic mass spectrometric techniques make it possible to detect the type of metabolic disturbances, to assess a risk for stone formation with the elevated urinary levels of lithogenic substances, to simulate a stone formation process by aggregatometry, which is of no importance in developing an algorithm of the pathogenetic treatment and prevention of stone formation in UL patients mainly at the early stage of the pathological process.
