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The copper alloy is widely used to prepare pipes in ocean engineering. The surface is washed and corroded by seawater for a long time, which gradually shortens the service life of the condenser tube. In order to improve the wear and corrosion resistance of copper alloy, a Ni60-WC coating was fabricated on a preheated copper alloy by laser cladding. Experiments on the Ni60-WC coatings were carried out by SEM, XRD, Vickers-microhardness meter, wear tester and electrochemical workstation. The microstructure, phases, hardness, wear and corrosion resistance were investigated. The results show that from the top to bottom, the microstructures were columnar dendrites, dendritic crystals and grains, respectively. The wear rate of the Ni60-WC coating was only 4.9 × 10−5 mm3·N−1·m−1, which was only 1.14% of copper substrate. In addition, the corrosion current density was 2.34 × 10−7 mA·mm−2, which was much lower than that of copper alloy substrate (1.14 × 10−6 mA·mm−2). The experimental results show that this Ni60-WC coating has a good metallurgical bonding and hardness, and it also has good wear and corrosion resistance, which is helpful to improve the service life of the condenser tube.

This study evaluated the effects of two management systems (battery cage and semi-intensive) on the digestive organ development and slaughter performance of Lushi green layer birds. Sixty layer chickens, Lushi green, seven weeks old were used. Thirty chickens were placed in each of the two systems. Ten (half male and half female) chickens from each management system were selected randomly for slaughter and relevant indexes were measured. Results showed that the liver, gizzard, pancreas and gizzard organ indexes of the roosters reared under the semi-intensive system were higher than those of the cage reared roosters (P<0.05). The digestive organ index of the hens reared under the semi-intensive system was also higher than that of the cage reared hens (P<0.05). The lengths of the jejunum, ileum, and ceca and the jejunum relatively small intestine index of the chickens reared under the semi-intensive system were higher than those of the cage reared chickens (P<0.05). The thigh muscle and abdominal fat yields of male and female chickens reared under the semi-intensive system were lower compared with those of the cage-reared ones (P<0.05). These results indicated that rearing method influences the slaughter performance and digestive organ development of Lushi chickens. The digestion and absorption abilities of chickens reared under the semi-intensive system were generally better than those of cage-reared ones.

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