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The effect of annealing temperature (TA) at 600–900 °C on structure and magnetic properties of the melt-spun Sm8.6Fe85.9Co4.3Zr1.2 alloys and its nitrides was investigated. Results show that the melt-spun powder is TbCu7-type SmFe9 single phase. X-ray diffractometer (XRD) Rietveld refinement shows that the lattice parameter a increases, c and c/a decrease with the increase in TA at 600–700 °C. This is due to the tendency of nitrogen entering into the 3f site (1/2, 0, 0) during the nitridation process, which is good for the magnetic properties. The phase transforms from TbCu7-type SmFe9 to Th2Zn17-type Sm2Fe17 at above 800 °C. Scanning electron microscopy (SEM) images show that the amount of surface defects of melt-spun powder which are harmful for magnetic properties decreases at first and then increases as TA increases. The coercivity (Hcj) and maximum magnetic energy product ((BH)max) of its nitrides increase first and then decrease as a function of TA. And the remanence (Br) always shows a decrease. The optimal magnetic properties of Hcj = 748 kA·m−1, Br = 0.92 T, (BH)max = 118 kJ·m−3 are obtained by annealing at 675 °C for 2 h and then nitriding at 460 °C for 10 h. [ABSTRACT FROM AUTHOR]

The melt-spun SmFe12Bx (x = 0, 0.50, 0.75, 1.00, 1.25 and 1.50) ribbons were prepared at 40 m·s−1, and their structure and magnetic properties were studied by powder X-ray diffraction (XRD), vibrating sample magnetometer (VSM) and transmission electron microscopy (TEM). XRD results indicate that SmFe12Bx alloys with 0.50 ≤ x ≤ 1.00 are composed of single-phase TbCu7-type structure. Moreover, it is found that the boron addition can inhibit the emergence of soft magnetic phase α-Fe and result in the increase in the axial ratio c/a. After annealing at 650 °C for 0.5 h, the metastable phase TbCu7 initially decomposes into the stable phase Sm2Fe14B (Nd2Fe14B-type) and α-Fe. The value of magnetic moment per Fe atom increases slightly from 1.75μB for boron-free sample to 1.80μB for the x = 0.75 sample and then decreases again. In addition, the best magnetic properties of maximum energy product [(BH)max] of 14.56 kJ·m−3, coercivity (Hcj) of 172.6 kA·m−1 and remanence (Br) of 0.45T are obtained for the SmFe12B1.00 alloy. Based on transmission electron microscopy (TEM) results, the average size of grains is around 197 nm for B-free sample and decreases to 95 nm for x = 1.00 sample, indicating that the addition of boron can refine grains. [ABSTRACT FROM AUTHOR]

Enhanced nonlinear refractive indices and absorption coefficients of nonstoichiometric SixC1−x with varying C/Si composition ratios from 0.51 to 1.83 grown by low-temperature plasma-enhanced chemical vapor deposition are demonstrated. When increasing the [CH4]/[CH4 + SiH4] fluence ratio from 70% to 92%, two Raman scattering signals at 795 and 970 cm−1 contributed by transverse and longitudinal optical modes of Si–C bonds are simultaneously enhanced in stoichiometric and C-rich SixC1−x samples, whereas the Si-associated Raman peak at 520 cm−1 decreases with increasing C/Si composition ratio. The C-rich SixC1−x film shows additional Raman scattering peaks at 1330 and 1580 cm−1, which are individually contributed by the diamond-like C–C bonds and the G peak of the graphite-like C–C bonds, respectively. The nonlinear refractive index increases to 1 ± 0.1 × 10−11 cm2 W−1 upon increasing the C/Si composition ratio up to 1.83, which is four orders of magnitude higher than that of bulk SiC. The increased C/Si composition ratio reduces the lattice constant and the effective mass of the SixC1−x film and enhances its nonlinear refractive index effectively. In comparison with the sp3-orbital C–C bond, the sp2-orbital C–C bond in SixC1−x films dominates the enhancement of nonlinear refractive index. By contrast, the nonlinear absorption coefficient changes sign and decreases magnitude when transferring the SixC1−x film from Si-rich to C-rich conditions. This sign reversal is primarily attributed to the conversion in the absorption mechanism from two-photon absorption to nonlinear saturable absorption. Unlike Si–Si bonds which favor two-photon absorption, the sp2-orbital C–C bonds with delocalized π-electrons essentially enhance the saturable absorbance. Hence, a higher nonlinear refractive index and a higher saturable absorption coefficient can be obtained by enriching the sp2-orbital C–C bonds in C-rich SixC1−x films. [ABSTRACT FROM AUTHOR]

Because non-resource factors, which can not be utilized by organisms but can influence biological growth, are important growing conditions for species, the study of the effect of these factors on the recovery of disturbed plants can contribute to the management of vegetation. Spartina alterniflora (smooth cordgrass), having invaded many marshes, was clipped to test the effects of submergence time and soil salinity on the recovery, as well as their underlying mechanisms. The results showed that salinity did not significantly affect the recovery of clipped invader, while longer-time submergence led to poorer recovery. Pentose phosphate pathway plays primary role in carbon metabolism of S. alterniflora roots. Along with the increase of submergence time, however, the activity of glucose-6-phosphate dehydrogenase in the roots of clipped S. alterniflora decreased; and the activities of lactate dehydrogenase and alcohol dehydrogenase firstly increased and then decreased. Ultimately, the activities of the three dehydrogenases became zero and thus asphyxiated the roots. Consequently, the clipped invader died after submergence of 12 days. Our case study demonstrates the recovery of invasive plants after disturbance depends on some non-resource conditions which can significantly influence the carbon metabolism of remaining parts. Thus, it can be predicted that identifying such non-resource conditions can help to develop an environment-specific management regime. The physical methods for removing aboveground biomass can be used to control invasive Spartina spp. in long-time submergence zones, whereas such methods need to be optimised for other zones. [ABSTRACT FROM AUTHOR]

The crystal structure and magnetic properties of SmFeCo ( x = 0, 1, 3, 5) alloys were studied by X-ray powder diffraction (XRD) and magnetic measurements. The ThZn-type structure of the as-cast state is changed to TbCu-type structure after quenching to a rotating molybdenum roll under certain velocity (12, 20, and 32 m·s). The (002) XRD peak appears and α-Fe phase disappears when the Co is added up to x = 5. Saturation magnetization of SmFe under different temperature shows 9 % change (112-102 A·m·g) when the temperature is higher than 200 K. The saturation magnetization is 115 A·m·g and coercivity is 0.304 T at 5 K for SmFe alloys. Increased saturation magnetization and decreased coercivity can be obtained for Co added up to x = 5 at 5 K. [ABSTRACT FROM AUTHOR]

An abstract of the article "Protective effect of glutathione on copper exposure to liver mitochondria of broilers," by Su Rong-Sheng and colleagues is presented.