Critical behavior and magnetic-entropy change of orthorhombic La0.7Ca0.2Sr0.1MnO3 J. Appl. Phys. 112, 093906 (2012) Reversible solid-state hydrogen-pump driven by magnetostructural transformation in the prototype system La(Fe,Si)13Hy J. Appl. Phys. 112, 083918 (2012) Magnetocaloric effect and nature of magnetic transition in nanoscale Pr0.5Ca0.5MnO3 J. Appl. Phys. 112, 083917 (2012) On the estimation of the magnetocaloric effect by means of microwave technique AIP Advances 2, 042120 (2012) Magnetocaloric properties of La0.7Ca0.3Mn16O3 and La0.7Ca0.3Mn18O3 manganites and their "sandwich"A systematic study of the conventional and inverse magnetocaloric effects and critical behaviors in Ni 50 Mn 50Àx Sn x (x ¼ 13 and 14) alloy ribbons has been performed. We show that although the magnetic entropy change around the second-order ferromagnetic-paramagnetic (FM-PM) transition (DS m % À4 J/kg K) in the austenitic phase is about five times smaller than that around the first-order martensitic-austenitic (M-A) transformation (DS m % 22 J/kg K), the refrigerant capacity (RC) -an important figure of merit -is about two times larger for the former case (RC % 160 J/kg) than for the latter case (RC % 75 J/kg). This finding points to an important fact that to assess the usefulness of a magnetocaloric material, one should not only consider DS m but also must evaluate both DS m and RC. Our critical analysis near the second-order FM-PM transition reveals that Sn addition tends to drive the system, in the austenitic FM phase, from the short-range (x ¼ 13) to long-range (x ¼ 14) FM order.

The ballistic transport properties of Cu nanowires (NWs) under electric fields are investigated using firstprinciples density function theory for future application as interconnects in microelectronics. It is found that as electric field strength increases, the amount of quantum conduction of a nonhelical atomic strand decreases, while that of a helical atomic strand is in an opposite tendency. The changes are decided by the changes of atomic layer distance of the NWs and the related electronic distribution along the axis of the NWs.

Polycrystalline samples of BaTiO3 doped with 2.0 at. % Mn were prepared by solid-state reaction at various temperatures (Tan) ranging from 500 to 1350 °C, used high-pure powders of BaCO3, TiO2, and MnCO3 as precursors. Experimental results obtained from x-ray diffraction patterns and Raman scattering spectra reveal that tetragonal Mn-doped BaTiO3 starts constituting as Tan ≈ 500 °C. The Tan increase leads to the development of this phase. Interestingly, there is the tetragonal-hexagonal transformation in the crystal structure of BaTiO3 as Tan ≈ 1100 °C. Such the variations influence directly magnetic properties of the samples. Besides paramagnetic contributions of Mn2+ centers traced to electron spin resonance, the room-temperature ferromagnetism found in the samples is assigned to exchange interactions taking place between Mn3+ and Mn4+ ions located in tetragonal BaTiO3 crystals.

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Six thiophenes were isolated and purified from ethanol extract of the roots of Echinops latifolius Tausch. Their structures were identified on the basis of spectral data. Among them, 5-(3-hydroxmethyl-3-isovaleroyloxyprop-1-ynyl)-2,2'-bithiophene (6) is a new compound, and 5-(3-hydroxy-4-isovaleroyloxybut-1-ynyl)-2,2'-bithiophene (5) was isolated from this plant for the first time.

Having based on x-ray absorption spectroscopy, we point out structural phase separation in polycrystalline Zn1-xMnxO ceramics prepared by solid-state reaction. The samples are single phase in the wurtzite structure as x < 0.04. A Mn-concentration increase with x ≥ 0.04 results in the formation of a secondary phase of tetragonal ZnMn2O4 spinel. The feature of x-ray absorption spectra for the Mn K edge reveals an existence of Mn2+ and Mn3+ ions in Zn1-xMnxO, which are responsible for room-temperature paramagnetism. Particularly, when Mn content is increased, there is a chemical shift of the absorption edge toward higher energies, indicating an increase in concentration of Mn3+ ions. Fourier analyses for the spectra of extended x-ray absorption fine structure (EXAFS) shows up the substitution of Mn for Zn sites in the ZnO host lattice. The parameters related to the local structure have been determined and discussed in detail.

The phase II metabolite of acetaminophen in filamentous fungi and actinomycetes separated from soil was investigated. Fifty-four filamentous fungi and twenty-seven actinomycetes were screened to transform acetaminophen. The metabolites of acetaminophen were assayed using liquid chromatography-tandem mass spectrometry. The only metabolite was subject to enzymatic hydrolysis to confirm its structure. Acetaminophen was converted into glucoside conjugate, by filamentous fungi JX1-60, LN17-2, LN20-1 and the yield of the conjugate was 60.01%, 44.27%, 100%, respectively, and no phase I metabolites were detected. Glucoside conjugation of acetaminophen in filamentous fungi differs from the phase II metabolism of glucuronidation in humans. The fungus LN20-1 could be a suitable model to synthesize glucoside conjugate of acetaminophen.