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Electronic structure and spin-related state coupling at ferromagnetic material (FM)/MgO (FM = Fe, CoFe, CoFeB) interfaces under biaxial strain are evaluated using the first-principles calculations. The CoFeB/MgO interface, which is superior to the Fe/MgO and CoFe/MgO interfaces, can markedly maintain stable and effective coupling channels for majority-spin state under large biaxial strain. Bonding interactions between Fe, Co, and B atoms and the electron transfer between Bloch states are responsible for the redistribution of the majority-spin state, directly influencing the coupling effect for the strained interfaces. Layer-projected wave function of the majority-spin state suggests slower decay rate and more stable transport property in the CoFeB/MgO interface, which is expected to maintain a higher tunneling magnetoresistance (TMR) value under large biaxial strain. This work reveals the internal mechanism for the state coupling at strained FM/MgO interfaces. This study may provide some references to the design and manufacturing of magnetic tunnel junctions with high tunneling magnetoresistance effect. [ABSTRACT FROM AUTHOR]

Ocean acidification is changing the nature of inorganic carbon availability in the global oceans. Diatoms account for ~ 40% of all marine primary productivity and are major contributors to the export of atmospheric carbon to the deep ocean. Larger diatoms are more likely to be stimulated by future increases in CO2 availability as a result of their low surface area to volume ratio and lower diffusive flux of CO2 relative to their carbon demand for growth. Here we quantify the effect of the partial pressure of carbon dioxide (), at levels of 190, 380, and 750 µL L-1, on the growth rate, photosystem II electron transport rate (ETR), and elemental composition for five diatom species ranging over five orders of magnitude in cell volume. Growth rates for all species were enhanced under 750 relative to 190 and 380 µL L-1, with little change in ETR or elemental stoichiometries, indicating an enhanced allocation of photochemical energy to growth under elevated . enhancement of growth rates was size dependent. Under 750 vs. 190 µL L-1 partial pressures, growth rate was enhanced by ~ 5% for the smaller diatom species to ~ 30% for the largest species examined. The size dependence of CO2- stimulated growth enhancement indicates that ocean acidification may selectively favor an increase in the growth rates of larger vs. smaller phytoplankton species in the sea, with potentially significant consequences for carbon biochemistry. [ABSTRACT FROM AUTHOR]

In this work, the novel TPA@C-NiZr-MOF catalyst is synthesized by the impregnation of tungstophosphoric acid (TPA) on the NiZr-based metal-organic framework (NiZr-MOF) followed by calcination up to 300 °C. The as-prepared catalyst materials were structurally, morphologically, and texturally characterized by XRD, FTIR, temperature programmed desorption of NH3 (TPD-NH3), N2 physisorption, SEM, TEM, and XPS. The prepared catalyst can be used as an efficient heterogeneous catalyst for biodiesel production from oleic acid (OA) with methanol. The results indicated that, in comparison to TPA@NiZr-MOF, the TPA@C-NiZr-MOF catalyst calcined at 300 °C exhibits excellent catalytic performance probably owing to the synergistic effect between TPA and metal oxide skeletons, high acidity, as well as larger surface area and pore size. Additionally, the TPA@C-NiZr-MOF catalyst can be reused in up to six cycles with an acceptable conversion. This study showed that the bimetallic MOF-derived composite materials can be used as an alternative potential heterogeneous catalyst toward biorefinery applications. [ABSTRACT FROM AUTHOR]

The existence of characteristic longitudinal optical and transverse optical phonons of cubic ZnO in ZnO nano-tetrapods is determined by Raman spectroscopy and first-principles calculations. Stacking sequence change at the boundary of the core and legs is also identified by high-resolution transmission electron microscopy. Based on this experimental and theoretical evidence, we demonstrate that the lattice structure of ZnO nano-tetrapods is hierarchical with a zinc blende core connecting to four wurtzite legs. Furthermore, we establish the atomic configuration and propose a formation mechanism induced by Laplace pressure in the initial growth stage of ZnO nano-tetrapods. [ABSTRACT FROM AUTHOR]

Cardiovascular complications have been well documented as the downside to conventional cancer chemotherapy. As a notable side effect of cisplatin (CDDP), cardiotoxicity represents a major obstacle to the successful treatment of cancer. It has been reported that Salvianolic acid B (SalB) possesses cardioprotective quality. However, the effect of SalB on cardiac damage caused by conventional cancer chemotherapy remains unclear. In this study, we clarified the protective effect of SalB on cisplatin-induced heart injury. Furthermore, in H9c2 cells, SalB dramatically reduced cisplatin-induced apoptosis and oxidative stress by modulating the nuclear factor erythroid-2-related factor 2 (Nrf2) signaling pathway. In conclusion, SalB had great potential in mitigating cisplatin-induced cardiac injury. Furthermore, more attention should be placed on natural active compounds containing SalB with antioxidant effects for the treatment of cardiomyopathy. [ABSTRACT FROM AUTHOR]