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This study investigated the effects of a traditional Chinese medicine formula (TCMF) on growth performance, and meat quality and fatty acid profiles of finishing pigs. Ninety 146-day-old Pietrain × Duroc × Landrace × Yorkshire pigs (84.1 ± 0.86 kg BW) were assigned randomly to three treatments with five replicates, six pigs per pen. Control group was fed basal diet and the other two groups were fed basal diet plus different doses of the TCMF (TCMF1: 2.5 g/kg feed; TCMF2: 5 g/kg feed). Growth performance was unaffected by TCMF ( P > 0.05). Pigs fed the TCMF had higher crude fat content in muscle ( P P P P > 0.05). The concentration of vaccenic acid in longissimus dorsi and of total unsaturated fatty acids in abdominal adipose tissue were increased by TCMF1 ( P P

Conventional Sm–Co-based alloys have low glass forming ability, and thus are difficult to quench to nanocrystalline structure by rapid solidification. In this paper, nanocrystalline [Sm, rare earth (RE)] Co6.4Si0.3Zr0.3C0.2 (RE = Ce, Sm, Gd, Ho, and Er) alloys have been obtained by melt spinning after compositional modification, as prepared alloys have a microstructure consisting of TbCu7-type SmCo7-based nanocrystals with the mean size of approximately 20 nm surrounded by a soft amorphous phase and a cobalt phase. After annealing at 600 °C for 1 h, the alloys were well crystallized and the grains grew up to ~100 nm. Both the coercivity and the remanence have been enhanced significantly by annealing. The effects of the substituted RE elements on the magnetic properties and thermal stability were investigated. An annealed Sm0.8Er0.2Co6.4Si0.3Zr0.3C0.2 alloy showed the highest remanence of 0.59 T and (BH)max of 58.8 kJ/ $\text{m}^{3}$ . Excellent thermal stability with the remanence temperature coefficient $\alpha $ of −0.0178%/°C and −0.0778%/°C at temperature range of 27 °C~200 °C and 27 °C~400 °C, respectively, was also obtained.

A magnetic-field-induced irreversible metamagnetic phase transition from antiferro- to ferromagnetism, which leads to an anomalous initial-magnetization curve lying outside the magnetic hysteresis loop, is reported in arc-melted SmCo7−xSix alloys. The transition temperatures are near room temperature, much higher than other compounds with similar initial curves. Detailed investigation shows that this phenomenon is dependent on temperature, magnetic field and Si content and shows some interesting characteristics. It is suggested that varying interactions between the Sm and Co layers in the crystal are responsible for the formation of a metastable AFM structure, which induces the anomalous phenomenon in as-cast alloys. The random occupation of 3g sites by Si and Co atoms also has an effect on this phenomenon.

The magnetic properties and thermal stability of melt spun SmCo6.4Si0.3Zr0.3 ribbons with various rare-earth (RE) elements substituted for Sm have been investigated. It is verified that the properties’ combination of SmCo7-based ribbons can be modified by selected RE substitution. The light RE Ce is beneficial for enhancing the saturation magnetization and the remanence, while the coercivity and thermal stability can be significantly improved by heavy REs Gd, Ho, and Er substitutions. The highest room-temperature coercivity of 1467 kA/m was achieved in the Sm0.7Gd0.3Co6.4Si0.3Zr0.3 ribbon. For the temperature range of 27 °C–200 °C, Gd is the best element for enhancing the thermal stability, and the optimal temperature coefficients $\alpha $ and $\beta $ are −0.032%/°C and −0.269%/°C, respectively. For the range of 27 °C–400 °C, Ho is the best element to improve the thermal stability, and the values of $\alpha $ and $\beta $ are −0.064%/°C and −0.19%/°C, respectively.

The effects of Zr and Si co-substitution on the magnetic properties, oxidation and corrosion resistances of TbCu 7 -type Sm–Co alloys have been investigated. Zr addition is very effective in promoting the formation of TbCu 7 -type structure and it contributes to the most of the coercivity enhancement. The largest coercivity of 1389 kA/m was obtained for SmCo 6.3 Zr 0.4 Si 0.3 alloy. Si addition can significantly improve the oxidation resistance. After exposure in air at 500 °C for 90 h, the thickness of the oxidation layer was just 106 μm for as-cast SmCo 6.4 Zr 0.3 Si 0.3 alloy compared to 230 μm for the SmCo 6.7 Zr 0.3 alloy. The room temperature coercivity of SmCo 6.4 Zr 0.3 Si 0.3 ribbon is as high as 884 kA/m after exposure at 300 °C in air for 10 min. The improved corrosion resistance for Si added alloys was also confirmed by polarization curve measurement. Zr and Si co-substitution provides a good approach for enhancing both the coercivity and resistances to oxidation and corrosion of the TbCu 7 -type Sm–Co alloy.

The effects of carbon addition on the structure and magnetic properties of rapidly quenched TbCu 7 -type SmCo 6.4 Si 0.3 Zr 0.3 alloy have been investigated. The alloys with a small amount of C addition ( x ≤0.2) showed single Sm(Co, M ) 7 phase, while ZrC phase appeared in the alloys with x =0.3 and 0.4. With the increase of C content, the grain size decreased from approximately 850 nm for x =0.1 to approximately 300 nm for x =0.4. The coercivity H c and maximum magnetic energy product ( BH ) max increased with the C content from x =0 to 0.2 and then decreased with excessive C addition. The optimal magnetic properties of H c =1577 kA/m, J r =0.53 T and ( BH ) max =52.1 kJ/m 3 were achieved for SmCo 6.4 Si 0.3 Zr 0.3 C 0.2 alloy with a grain size of 600–700 nm, which is close to the single domain size of TbCu 7 -type Sm(Co,Zr) 7 alloy. Furthermore, C addition also improved the thermal stability by reducing the absolute values of temperature coefficients of remanence and coercivity.

The effects of wheel speed, Zr content, post-ball milling process and heat treatment on the structure, anisotropy, magnetic properties and phase transition of the melt-spun SmCo7−xZrx alloys were investigated. The crystallographic c-axis is parallel to the ribbon plane for the ribbons prepared at low speeds of 5 and 15 m/s, and this orientation is reduced at higher speeds. The out-of-plane coercivity of SmCo6.8Zr0.2 ribbon increases from 123 kA/m for 5 m/s to 1076 kA/m for 60 m/s. Zr doping improves the hard magnetic properties and the in-plane coercivity of SmCo7−xZrx alloys increases with the Zr content from 592 kA/m for x=0.1 to 1376 kA/m for x=0.4. The Rietveld refinements and theoretical analysis reveal that Zr atoms occupy the 2e site. The coercivity mechanisms are different for the alloys with various Zr contents. The ball milling process could enhance the coercivity and remanence of the ribbons due to the grain refinement and the precipitation of Co phase. Heat treatment can further modify the magnetic properties of the alloys. SmCo6.7Zr0.3 alloy heat treated at 400 °C has the high maximum energy product (BH)max of 64.5 kJ/m3, where the coercivity was enhanced to 1560 kA/m by 650 °C heat treatment. In addition, the SmCo7−xZrx alloys exhibit excellent hard magnetic properties at elevated temperatures.

According to the current operating experiences, the dominating failure mechanism of the UK transmission power transformer population has been verified by the forensic tear-down investigations to be of a random manner. In long term consideration, it is widely acknowledged that due to the thermal aging, the mechanical breakdown of the insulating paper is responsible to the ultimate failure of the transformer. Conventionally the insulating paper's thermal usage shall only be reliably learnt via measuring paper's degree of polymerization (DP) after transformer scrapping, which is infeasible in assessing the active units. In dealing with this problem, a systematic model, based on the thermal model in IEC transformer loading guide 60076-7, is presented in this paper to estimate individual active transformer's thermal life via evaluating its operating condition and thermal design characteristics. The model features the incorporation of the practical aging mechanisms of the insulating paper, and the derivation of the conventionally unknown hot-spot factor (HSF) via utilizing the information gained from scrapped units. As the modeling result, the thermal life expectancy of 185 transformers has been estimated as 83 years. A thermal life matrix is also presented as an attempt to reveal the general trend of the transformer's thermal life under different combinations of load and thermal design characteristic.