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To enhance the friction and wear performance of TC4 titanium alloy, micro‐arc oxidation(MAO) coating was fabricated on its surface, which was subsequently sealed with a modified graphene/epoxy resin coating to form a composite coating of micro‐arc oxidation ‐modified graphene/epoxy resin. The friction and wear performance of samples sealed by different methods are analyzed and characterized using a scanning electron microscope, an energy spectrometer, and friction and wear tester. The results indicate that the modified graphene/epoxy resin coating successfully combines with the micro‐arc oxidation coating and fills the pores, thereby enhancing the friction and wear performance of the composite coating. In tribological tests, compared with other samples, this composite coating has a lower friction coefficient and specific wear rate, showing excellent friction and wear performance, and its main wear mechanism is adhesive wear. Therefore, the fabrication of a micro‐arc oxidation ‐modified graphene/epoxy resin composite coating can improve the friction and wear performance of TC4 titanium alloy. [ABSTRACT FROM AUTHOR]

The corrosion inhibition behaviors of 2′-hydroxy-acetophenone for AZ91D magnesium alloy in ASTM D1384-87 corrosive water (model water) were investigated using weight loss and electrochemical measurements. The surface morphologies and composition of films formed on magnesium alloy in solutions with and without 2′-hydroxy-acetophenone were examined by scanning electron microscope and Fourier transform infrared spectrum. The results show that inhibition efficiency first increases and then decreases with the increasing 2′-hydroxy-acetophenone concentration, its maximum value is at 50 ppm. It is considered that 2′-hydroxy-acetophenone anions can chelate with the Mg2+ and form a 2′-hydroxy-acetophenone-Mg complex on the magnesium alloy surface, hindering the corrosion development of magnesium alloy. [ABSTRACT FROM AUTHOR]

Objective: To investigate the feasibility and safety of robotic-assisted radical resection of gastric and colorectal cancer., Methods: The clinical data of 305 patients who received radical resection of gastric cancer and 342 patients who received radical resection of colorectal cancer both accomplished by the da Vinci robotic surgical system at the Southwest Hospital, Third Military Medical University from March 2010 to December 2014 were retrospectively analyzed. In gastric cancer group, radical total gastrectomy were performed in 69 cases, proximal gastrectomy in 11 cases, distal gastrectomy in 213 cases and 12 cases of gastric stump cancer.In colorectal cancer group, radical resection of the right colon were performed in 6 cases, left colon in 4 cases, transverse colon in 1 case, sigmoid colon low anterior resection procedure in 24 cases, rectal low anterior resection procedure in 222 cases, abdominoperineal excision procedure in 79 cases and Hartmann procedure in 6 cases., Results: All cases had robotic-assisted radical resection successfully. In gastric cancer group, the mean operation time was (226±62) minutes, the mean blood loss was (125±77) ml, the mean number of harvested lymph nodes was 34±10; the mean time for patients taking normal activity was (3.2±1.5) days, the mean time for gastrointestinal function recovery was (3.1±1.3) days, the mean time for taking liquid food was (3.5±1.9) days. The mean hospitalization was (7.9±3.7) days postoperatively. In colorectal group, the mean operation time was (181±61) minutes, the mean blood loss was (110±93) ml, the mean number of harvested lymph nodes was 19±6; the mean time for patients taking normal activity was (2.9±1.5) days, passage of first flatus was (2.7±1.7) days. The mean hospitalization was (7.1±1.6) days postoperatively. Surgical complications occurred in 28 patients (9.2%) of gastric cancer group and 30 patients (8.8%) of colorectal cancer group, all the cases were recovery before leaving hospital with non-operation therapy. The short-term efficiency was obvious., Conclusion: Robotic-assisted radical resection for gastric and colorectal cancer is a feasible and safe surgical procedure combined the minimal trauma and fast recovery.