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Laser cladding technology can obtain a cladding layer with good metallurgical bonding with the substrate and excellent performance. In situ growth of hard phase can effectively solve the problem of uneven distribution of reinforcements directly doped with hard particles. In this paper, 45# steel was adopted as the matrix material, WO3, B4C, Al, and Ni60 powder were used to prepare laser cladding and in situ synthesized WC (Tungsten Carbide) hard phase reinforced Ni‐based cladding layers. The effects of different laser cladding parameters, powder particle size, hard phase content on the microstructures and electrochemical properties of in situ synthesized WC hard phase reinforced Ni‐based cladding layer were analyzed. The results revealed that when the (WO3 + B4C + Al) mixed powder content was 25%, the bulk particles of WC phase in the cladding layer were most uniformly distributed in the cladding layer, which enhances the mechanical properties of the cladding layer. When the B4C particle size was 5 μm, the microhardness of the cladding layer was significantly higher than other cladding layers, and the enhancement mechanism of hardness by B4C is due to the Orowan strengthening caused by too small particle size of B4C. [ABSTRACT FROM AUTHOR]

A kind of wear‐resistant diamond‐like carbon (DLC) films doped with Ni, N, and multiwalled carbon nanotubes (MWCNTs) are synthesized on Ti–6Al–4V titanium alloy by a combined method of pulsed electrodeposition and liquid‐phase electrodeposition. The effect of different concentrations of MWCNTs on the microstructure and friction mechanism of Co‐DLC films is investigated. The results show that the polydimethyl diallyl ammonium chloride (PDDA)‐MWCNTs complex tend to deposit parallel to the substrate. Benefiting from the "bridging" effect of the MWCNTs between the cluster structures, it effectively reduces the protrusions on the surface of the films. When the concentration of MWCNTs is 0.06 g L−1, the surface microstructure of the films is uniform and dense, and the films present a low ID/IG value (0.57) and a high sp3‐C content. The Raman and X‐ray photoelectron spectroscopy patterns reveal that the Ni/N/MWCNTs‐DLC films are typical amorphous carbon films. Furthermore, the micro‐indentation hardness of the Co‐DLC films reaches 513.24 HV. The lubricated Ni/N/MWCNTs‐DLC films significantly improve the frictional wear properties of the titanium alloy surface, which is mainly attributed to the homogeneous and dense structure and the low friction coefficient (0.146) and wear loss (1.40 × 10−5 kg m−1). [ABSTRACT FROM AUTHOR]

Background: Osseointegration of implant materials with surrounding tissues is crucial for their long-term success., Objective: The aim of the present study was to investigate the extent of physisorption of polymers on a titanium alloy (Ti6Al4V) surface. In addition, the water contact angles on the physisorbed coatings were measured to compare the hydrophilicity of the modified surfaces., Methods: Ti6Al4V disks (13-mm diameter) were prepared to evaluate polymer adsorption on the alloy surface. The surface hydrophilicity was evaluated by contact angle (Θ) measurement. Physisorption of polymers on the surface was evaluated quantitatively by a colorimetric method., Results: The largest contact angles were recorded on samples polished with silicon carbide papers of 1200 and 500 grit (Poli1200 and Poli500 samples: 97.3 ± 4.8 and 84.8 ± 11.0, respectively). Treatment of polished samples with Kroll solution remarkable reduced the contact angles to 46.8 ± 11.6 and 58.6 ± 11.5 for Poli500+Kroll and Poli1200+Kroll, respectively. Contact angles were further reduced in response to PolyNaSS and PAA treatment. Regardless of surface treatment, there was no significant difference in the contact angles on surfaces after SiC 500 and 1200 grit polishing., Conclusions: Physisorbed polymer coatings (such as PAA) on the Ti6Al4V surface can reduce the contact angle and improve the hydrophilicity and wettability of the alloy surface. Moreover, physisorption is a simple technique that does not require any special equipment.

Objective: To understand the endemic dynamic and situation of schistosomiasis in the Xixi National Wetland Park., Methods: The surveillances of Oncomelania hupensis snail situation and the schistosome infection status of the permanent residents and floating population in the Xixi National Wetland were conducted annually from 2012 to 2014 according to the Surveillance Programs of Schistosomiasis in Surveillance Sites of Zhejiang Province., Results: From 2012 to 2014, accumulatively 12.31 hm2 of area, 4965 m2 of vegetation and 75,379 alien plants were surveyed in the Xixi National Wetland Park, and no Oncomelania snails were found. The seropositive rates in the permanent residents and floating population were 0.71% (5/706) and 1.36% (25/1 834), respectively, and 1 imported chronic schistosomiasis case was found in 2014. Totally 3 006 floating personnel were involved in the investigation of infection status and awareness on knowledge of schistosomiasis control in 2013, the sero-positive rate was 0.63% (19/3 006), and the rates of those from endemic and non-endemic areas were 1.00% (15/1 503) and 0.27% (4/1 503), respectively, and the difference was statistically significant ( χ2 = 6.41, P < 0.05). The results of the fecal examinations among the seropositive cases were all negative. The awareness rates on the Regulation of Schistosomiasis Control and Prevention as well as related knowledge about Oncomelania snails were low. The indoor survival experiment of Oncomelania snails showed the survival rates of Oncomelania snails were 58.33% and 1.25% after observing for 3 and 6 months respectively., Conclusions: The Xixi National Wetland Park is suitable for Oncomelania snails to inhabit and breed. The imported cases in floating population pose a serious threat to the endemic situation of schistosomiasis in local. In the future, the surveillance on snails and floating population as well as the health education should be strengthened.