Geometric bionics: Lotus effect helps polystyrene nanotube films get good blood compatibility

Various biomaterials have been widely used for manufacturing biomedical applications including artificial organs, medical devices and disposable clinical apparatus, such as vascular prostheses, blood pumps, artificial kidney, artificial hearts, dialyzers and plasma separators, which could be used in contact with blood^1^. However, the research tasks of improving hemocompatibility of biomaterials have been carrying out with the development of biomedical requirements^2^. Since the interactions that lead to surface-induced thrombosis occurring at the blood-biomaterial interface become a reason of familiar current complications with grafts therapy, improvement of the blood compatibility of artificial polymer surfaces is, therefore a major issue in biomaterials science^3^. After decades of focused research, various approaches of modifying biomaterial surfaces through chemical or biochemical methods to improve their hemocompatibility were obtained^1^. In this article, we report that polystyrene nanotube films with morphology similar to the papilla on lotus leaf can be used as blood-contacted biomaterials by virtue of Lotus effect^4^. Clearly, this idea, resulting from geometric bionics that mimicking the structure design of lotus leaf, is very novel technique for preparation of hemocompatible biomaterials

Numerical investigation of scale effect of various injection diameters on interaction in cold kerosene-fueled supersonic flow

Abstract: The incident shock wave generally has a strong effect on the transversal injection field in cold kerosene-fueled supersonic flow, possibly due to its affecting the interaction between incoming flow and fuel through various operation conditions. This study is to address scale effect of various injection diameters on the interaction between incident shock wave and transversal cavity injection in a cold kerosene-fueled scramjet combustor. The injection diameters are separately specified as from 0.5 to 1.5mm in 0.5mm increments when other performance parameters, including the injection angle, velocity and pressure drop are all constant. A combined three dimensional Couple Level Set & Volume of Fluids (CLSVOF) approach with an improved K-H & R-T model is used to characterize penetration height, span expansion area, angle of shock wave and sauter mean diameter (SMD) distribution of the kerosene droplets with/without considering evaporation. Our results show that the injection orifice surely has a great scale effect on the transversal injection field in cold kerosene-fueled supersonic flows. Our findings show that the penetration depth, span angle and span expansion area of the transverse cavity jet are increased with the injection diameter, and that the kerosene droplets are more prone to breakup and atomization at the outlet of the combustor for the orifice diameter of 1.5mm. The calculation predictions are compared against the reported experimental measurements and literatures with good qualitative agreement. The simulation results obtained in this study can provide the evidences for better understanding the underlying mechanism of kerosene atomization in cold supersonic flow and scramjet design improvement

Determination of Five Synthetic Colorants in Grain Food by High Performance Liquid Chromatography-tandem Mass Spectrum

A new application of baking soda was developed, the synthetic colorant in cereal was extracted by adding with methanol solution in this paper.To develop new uses of edible bicarbonate,synthetic colorants were extracted from cereals by adding methanol water solution of edible bicarbonate in this paper, Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS)was used to test standard recovery.The extraction effect of edible bicarbonate of soda on five synthetic colorants of sunset yellow, amaranth red, carmine red, alluvium red and bright blue in cereals was investigated.The sample was extracted with 70 mL 40% methanol water vortexed with 1g edible baking soda, purified with Strata X-AW SPE column and determined.The results showed that, a good linearity was observed between 0.1 and 1.4μg/mL, and for the 5 synthetic colorants, the limit of detection was between 0.07 and 0.50 μg/g.The recoveries of the 5 synthetic colorants of different food substrates at different spiked levels (1, 2 and 10 μg/g) were all found to be in the recovery range specified in GB/T27404.The recoveries for the 5 synthetic colorants were found between 80.0% and 110% with RSD from 0.7% to 5.1% (n=6).Hence, baking soda added to 40% methanol water solution can be used to extract synthetic colorants from grain products with simple operation, accurate results, high efficiency and environmental protection