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1. This experiment was conducted to evaluate the effects of dietary isoleucine (Ile) on reproductive performance and certain indices of metabolism and oxidative stress in Chinese yellow-feathered broiler breeder hens.2. A total of 600, 40-week-old Chinese yellow-feathered broiler breeder hens were fed a basal diet formulated with maize, corn gluten meal and spray-dried blood cell meal containing 3.3 g/kg Ile, or supplemented to contain 4.5, 5.7, 6.9, or 8.1 g/kg Ile for five weeks. Each dietary treatment had six replicates with 20 birds per replicate. After three weeks of receiving the trial diets, 24 eggs were collected at random from each replicate to measure egg quality. Starting after four weeks of treatment, 50 settable eggs per replicate were collected for 7 d in succession for hatching. After five weeks of being fed the treatment diets, birds were slaughtered for tissue and organ collection.3. For the overall period, laying rate, egg weight, egg mass and hatchling weight linearly (P 0.05) and quadratically (P 0.05) increased with dietary Ile levels. Final body weight, feed intake and relative liver weight of birds fed 3.3 g/kg Ile was lower compared to birds fed the other diets (P 0.05). There was no effect of Ile level on egg quality (P 0.05). Hatchling weight was linearly (P 0.05) and quadratically increased (P 0.05) in line with dietary supplemental Ile.4. After three weeks on the trial diets, birds fed the diet containing 3.3 g/kg Ile had decreased blood TG concentrations compared to breeders fed 6.9 or 8.1 g/kg Ile (P 0.05). Activities of CK were significantly higher in breeders fed the 3.3 g/kg Ile diet compared to all other levels of dietary Ile after five weeks of treatment. A quadratic effect (P 0.05) was evident for glucose at 8.1 g/kg Ile level. After five weeks of treatment, plasma TG concentrations in birds fed 3.3 g/kg Ile were significantly lower than in birds fed all other levels of Ile. Glucose concentrations in breeder hens receiving the 3.3 g/kg Ile diet were lowest and the highest concentrations were in birds fed 5.7 g/kg Ile (P 0.05). Plasma activities of LDH were highest in breeders on the 3.3 g/kg Ile diet but were only significantly different (P 0.05) for birds fed 5.7 g/kg Ile.5. The current study indicated that Ile deficiency decreased reproductive performance and appeared to serve as a stressor. The optimal dietary Ile for Chinese yellow-feathered broiler breeder hens in the laying period was 5.79 g/kg feed (0.75 g/d).

The wear behavior of as-cast AZ51 alloy was investigated using a pin-on-disc configuration within a load range of 20–380 N and a sliding speed range of 0.1–4.0 m/s under dry sliding conditions. The coefficient of friction and wear rate were measured as a function of applied load at various sliding speeds. Morphologies and chemical compositions of worn surfaces were analyzed for determination of wear mechanisms using scanning electron microscope (SEM) and energy-dispersive X-ray spectrometry (EDS). Microstructural evolution, plastic deformation, and hardness of the subsurfaces as well as worn surface hardness were characterized by confocal scanning laser microscopy and hardness testing for the establishment of a corresponding relationship between microstructural evolution and mild to severe wear transition in AZ51 alloy. The results show that there exists a strong relationship between wear behavior and subsurface microstructural evolution; that is, surface oxidation and strain hardening originating from pl...

Chlorophytum comosum was used to remediate the artificially polluted soil in a pot experiment under greenhouse conditions. The results showed that the activity of soil enzyme increased significantly in soil planted with C. comosum compared to soil not planted with C. comosum, while the concentration of cadmium in the soil reduced. The accumulation at 10 mg kg−1 cadmium was above 100 mg kg−1, and up to 1,522 and 856 mg kg−1 in the root and the aboveground part at 200 mg kg−1 cadmium concentration. In conclusion, C. comosum is a potential Cd-hyperaccumulator and of great value in remediation cadmium-contaminated soils.

Thin films of (Ti,Al)N with different Al contents were co-deposited using one Ti and one Al targets by radio frequency (RF) pulsed magnetron sputtering. Their composition, microstructure, nanohardness, surface morphology and deposition process were investigated by energy dispersive spectrometer system, X-ray diffraction, nanoindentation, atomic force microscopy and optical emission spectrum. A face cubic centred (fcc) TiN (B1) structure was found in the thin films when Al target power was low. When Al target power was increased, an additional hexagonal AlN (B4) structure appeared. With increasing Al content, the resulting films gradually changed from B1 structure to that of B4, accompanying with decrease of the lattice constant of B1 structure. Simultaneously, the preferred orientation of B4 structural thin films gradually transformed from (111) to (200). The mode of thin films transformed from island to fibre, subsequently to column with increasing Al target power. Optical emission spectrum anal...

The general asymptotic waveform evaluation (GAWE) is proposed for computing the radar cross section (RCS) of an arbitrarily shaped three-dimensional perfect electric conductor (PEC). In the novel technique, the solution of a matrix equation is approximated by the fraction expression with a numerator of vector summation and a denominator of vector summation. The comparison of the GAWE and the traditional asymptotic waveform evaluation (AWE) is also given. Finally, the RCS for different PEC objects such as a square plate, an angular-plate and a cube are computed. The results prove that the extrapolation frequency range in GAWE is wider than that in AWE under the same order derivative. Meanwhile, the computed speed in GAWE is hardly different with that in AWE.