Synergy effect between tetracycline and Cr(Ⅵ)on combined pollution systems driving biochar-templated Fe_(3)O_(4)@SiO_(2)/TiO_(2)/g-C_(3)N_(4) composites for enhanced removal of pollutants

Biochar-coupled Fe_(3)O_(4)@SiO_(2)/TiO_(2)/g-C_(3)N_(4) composites were successfully constructed through simple sol-gel and calcination methods.The composites efficiently removed high-concentration toxic tetracycline(TC)by means of·OH and·O_(2)^(−),whose removal rate exhibited 91.88%during 3 h,and the degradation rate constant reached up to 0.0068 min^(−1).The excellent performance can be attributed to the high specific surface area,enhanced visible light response,the introduction of magnetic nanoparticles and biochars expediting charge transfer,Z-scheme heterojunction enhancing the spatial separation of photo-generate carriers and,importantly extraordinary adsorption capacity of 147.96 mg g^(−1).Moreover,the composites showed the most excellent efficiency under the calcination temperature of 450℃,and exhibited good stability with tolerance to a wide range of pH and anions.Interestingly,a synergistic photocatalytic effect was discovered in the TC/Cr(Ⅵ)combined pollution systems,resulting in significantly improved removal of Cr(Ⅵ).Besides,the photocatalytic mechanism and degradation path of tetracycline were also elucidated.All these findings suggested the as-synthesized catalyst was an excellent photocatalyst for removal of TC/Cr(Ⅵ)-contaminated water.

Surface roughness characteristics effects on fluid load capability of tilt pad thrust bearings with water lubrication

The effects of surface roughness characteristics on the fluid load capacity of tilt pad thrust bearings with water lubrication were studied by the average flow model.The flow factors utilized in the average flow model were simulated with various surface roughness parameters including skewness,kurtosis and the roughness directional pattern.The results indicated that the fluid load capacity was not only affected by the RMS roughness but also by the surface roughness characteristics.The fluid load capacity was dramatically affected by the roughness directional pattern.The skewness had a lower effect than the roughness directional pattern.The kurtosis had no notable effect on the fluid load capacity.It was possible for the fluid load capacity of the tilt pad thrust bearings to be improved by the skewness and roughness direction pattern control.