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Both theoretical calculations and experiments indicate that a monolayer CoSb/SrTiO 3 film has high-temperature superconductivity resembling the case of FeSe/SrTiO 3. However, no superconductivity was found in the bulk CoSb, even under high pressure. Moreover, the magnetic properties of CoSb have always been controversial. Here, we have studied the electrical property, magnetic property, and X-ray photoelectron spectroscopy (XPS) of CoSb single crystals. Electrical and magnetic transportation measurements reveal that CoSb is a Pauli paramagnetic metal with non-Fermi liquid behavior. The XPS results showed that both Co and Sb in CoSb are in the zero-valence state, and they form an alloy in which the metallic bond is dominant. The Pauli paramagnetism of CoSb originates from its itinerant electrons. Therefore, unveiling the electronic states of CoSb single crystal not only help us understand its magnetic properties, but would also pave the way for searching for the possible high-temperature superconductivity. • CoSb single crystals with large size were synthesized. • CoSb is a Pauli paramagnetic metal with non-Fermi liquid behavior. • XPS analysis indicates that both Co and Sb are in the zero-valence state in CoSb. • The Pauli paramagnetism of CoSb originates from its high-density itinerant electrons. [ABSTRACT FROM AUTHOR]

We reported the magnetism, magnetic phase transition behavior and magnetocaloric effect of the ternary Dy 2 CuSi 3 and Ho 2 CuSi 3 compounds. A second order magnetic phase transition from a paramagnetic (PM) to ferromagnetic (FM) state around their respective Curie temperatures were confirmed by using the magnetic measurements and rescaled magnetic entropy change curves in both compounds. A large magnetic entropy change was obtained with the absence of thermal and magnetic hysteresis loss in both compounds. The maximal magnetic entropy change (-Δ S M max ) reach 18.3 and 28.3 J/kg K for a magnetic field change of 0–70 kOe in Dy 2 CuSi 3 and Ho 2 CuSi 3 , respectively. The corresponding values of relative cooling power ( RCP ) are evaluated to be 460 J/kg and 627 J/kg, respectively. [ABSTRACT FROM AUTHOR]

The precipitation-hardenable nickel–chromium-based superalloy X-750 exhibits excellent mechanical properties at high-to-cryogenic temperatures. However, little is known about its other properties, even though it is used in a wide range of applications. To elucidate the additional properties of X-750, we studied the effects of its nanostructural evolution on both its mechanical and magnetic properties. We found that precipitation not only mechanically hardens this superalloy, but also induces soft magnetism as well as notable magnetic losses at ultralow temperatures. This information should aid the design of superconducting instruments based on the X-750 superalloy as a structural material. [ABSTRACT FROM AUTHOR]

Abstract: Dopamine conjugated protoporphyrin, PPD, was prepared by the coupling reaction of protoporphyrin IX and dopamine in the presence of dicyclohexylcarbodiimide (DCC) and N-hydroxysuccinimide (NHS) in DMF. The crude product was washed with ethanol–cyclohexane (1:1) mixture to remove dicyclohexylurea (DCU). Previously prepared Fe3O4 nanoparticles were coated with PPD (sub-7nm monosize) by sonication in the methanol. The porphyrin coated Fe3O4 nanoparticles, PPDNP were separated by permanent magnet. The microstructure and magnetic properties of magnetic nanoparticles were characterized by XRD, TEM, FT-IR, and VSM. It is found that the nanoparticles have high crystallinity with distinct lattices and the magnetic measurements reveal their well-defined superparamagnetic behavior at room temperature. [Copyright &y& Elsevier]

Abstract: We report the magnetic characterization of ZnO nanopowders with an average grain size of about 50nm prepared by sol–gel method. At room temperature, ZnO nanopowders exhibit diamagnetism like bulk ZnO. However, strong paramagnetism was observed at 4K. With increasing temperature, ferromagnetic to paramagnetic transition happens at around 90K. Paramagnetism changes to diamagnetism at around 100K, which is due to the competition between the paramagnetism from defects and diamagnetism from the bulk ZnO. Our work clearly demonstrates that the interaction between the defects is short-range. Thus the interaction between the defects is weak due to low defect concentration. It is suggested that a high defect concentration is needed for room temperature ferromagnetism. [Copyright &y& Elsevier]