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Abstract La 0.7 Ca 0.3 Mn 0.95 M 0.05 O 3 (M = Mn, Al, 0.5Al+0.5In, and In) perovskites (AB O 3) were studied with x-ray diffraction and AC susceptibility measurements. We provide the phenomenological expressions for the electron bandwidth, W , and Curie temperature, T C , to describe the variance in these values caused by the change of the degree of doping in the A - position and of the type of dopant in the B -position. The observed decrease in T C with doping is found to be mostly related to the difference in the electron configuration of Mn3+ ions and dopant M , and partially caused by the change in the local crystal structure because of the difference in the Mn3+- and M- ion radii. [ABSTRACT FROM AUTHOR]

• Thermal reduction of LaNiO 3 and perovskite-like La 3 Ni 2 O 6+ x occurs in two stages;. • Their crystal structure and morphology are almost retained during the first stage;. • This process is accompanied by the appearance of Ni nanoparticles at the surface;. • Apart from high temperature redox exsolution, this process occurs at t ≤ 400 °C;. • As-obtained Ni/oxide nanocomposites demonstrate a significant catalytic activity. Thermal decomposition of the citrate-gel precursors with La/Ni = 1/1 and La/Ni = 3/2 results in the formation at T ≥ 700 °C the single phase perovskite LaNiO 3 and the disordered perovskite-like phase La 3 Ni 2 O 6+ x. A reduction of both compounds during thermal processing in a 5 % H 2 /Ar gas mixture proceeds in two definite steps. The first stage of LaNiO 3 reduction at 250 - 350 °C results in the formation of an O-deficient La 2 Ni 2 O 5 compound. A similar process during the reduction of La 3 Ni 2 O 6+ x occurs at 300–400 °C with the lack of significant changes in the XRD pattern. An unusual feature of these processes deals with the formation of Ni0 nanoparticles on the surface of both reduction intermediates at 350–400 °C while similar processes are usually observed during redox exsolution of metals from several complex oxides at T > 700 °C only. As-obtained Ni/La x NiO y nanocomposites demonstrated significant catalytic activity and excellent selectivity and stability in the Sabatier reaction. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The liquid hydrocarbon sorption behavior of expanded graphite (EG) enhanced with iron phases (α-Fe, α-Fe2O3, Fe3O4, and FeOOH) was studied. Iron phases were shown not to affect the porous structure of EG or its sorption capacity. The utilization of the three EG samples with the high magnetic saturation (10.5, 30, and 35emu/g) as magnetic sorbents for the petroleum products spill response was considered. The requirements in values of the magnetic saturation of EG to be attracted by a magnet were estimated. Also, the water sorption of EG was studied, which competes with liquid hydrocarbons for pore spaces. The method of the dynamic contact angle measurement in water is suggested as a useful characterization of EG surface chemistry for this application. [Copyright &y& Elsevier]

iPSC-derived cells (from induced pluripotent stem cells) are a useful source that provide a powerful and widely accepted tool for the study of various types of human cells in vitro. Indeed, iPSC-derived cells from patients with hereditary diseases have been shown to reproduce the hallmarks of these diseases in vitro, phenotypes that can then also be manipulated in vitro. Quantitative reverse transcription PCR (qRT-PCR) is often used to characterize the progress of iPSC differentiation, validate mature cell types and to determine levels of pathological markers. Quantitative reverse transcription PCR (qRT-PCR) is used to quantify mRNA levels. This method requires some way of normalizing the data, typically by relating the obtained levels of gene expression to the levels of expression of a “house keeping gene”, a gene whose expression is presumed not to change during manipulation of the cells. In the literature, typically only one such reference gene is used and its stability of expression during cell manipulation is not demonstrated. We are not aware of any study systematically looking at the expression of such genes in human iPSC or during their differentiation into neurons. Here we compare the expression of 16 reference genes in iPSC, neural stem cells (NSC) and neurons derived from iPSC. The applications GeNorm and NormFinder were used to identify the most suitable reference genes. We showed that ACTb , C1orf43 , PSMB4 , GAPDH and HMBS have the most stable expression. The use of these reference genes allows an accurate normalization of qRT-PCR results in all the cell types discussed above. We hope that this report will help to enable the performance of proper qRT-PCR results normalization in studies with iPSC-derived cells and in disease-modeling reports. [ABSTRACT FROM AUTHOR]