Application of shear-sensitive liquid crystal coating to visualization of transition and reattachment in compressor cascade

The present paper aims at introducing Shear-Sensitive Liquid Crystal Coating(SSLCC)technology into compressor cascade measurement for the first time and serves as a basis for better understanding of the influence from the boundary layers. Optical path layout, which is the most significant difficulty in internal flow field measurement, will be solved in this paper by selfdesigned image acquisition device. Massive experiments with different Mach number and incidence are conducted at a continuous subsonic cascade wind tunnel to capture the boundary layer phenomenon. Image processing methods, such as Three-Dimensional(3-D) reconstruction and Hue conversion, are used to improve the accuracy for transition position detection. The analysis of the color-images indicates that complex flow phenomena including transition, flow separation,and reattachment are captured successfully, and the effect of Mach number and incidence on the boundary layer flow is also discussed. The results show that: the Mach number has a significant effect on transition position; the incidence has little effect on transition position, but it has a great impact on the transition distance and leading-edge separation; influenced by the end-walls, the reattachment occurs in advance under positive angle of attack conditions.

Molten-LiCl induced thermochemical prelithiation of SiOx:Regulating the active Si/O ratio for high initial Coulombic efficiency

The low initial Coulombic efficiency(ICE)of SiOx anode caused by the irreversible generation of LiySiOz and Li20 during lithiation process limits its application for high energy-density lithium-ion batteries.Herein,we report a molten-salt-induced thermochemical.prelithiation strategy for regulating the electrochemically active Si/O ratio of SiOx and thus enhancing ICE through thermal treatment of pre-synthesized LiNH2-coated SiOx in molten LiCl at 700℃.Bulk SiOx micro-particle was transformed into pomegranatelike prelithiated micro-cluster composite(M-Li-SiOx)with SiOx core and outer nano-sized agglomerates consisting of Li2Si20s,SiO2,and Si.Through the analysis of the reaction intermediates,molten-UC!could initiate reactions and promote mass transfer by the continuous extraction of oxygen component from SiOx particle inner in the form of inert Li2Si20s and SiO2 nanotubes to realize the.prelithiation.The degree of prelithiation can be regulated by adjusting the coating amount of LiNH2 layer,and the resulted M-Li-SiOx displays a prominent improvement of ICE from 58.73%to 88.2%.The graphite/M-Li-SiOx(8:2)composite electrode delivers a.discharge capacity of 497.29 mAh·g^(-1) with an ICE of 91.79%.By pairing graphite/M-Li-SiOx anode and LiFeP04 cathode in a full-cell an enhancement of energy density of 37.25%is realized compared with the full-cell containing graphite/SiOx anode.Furthermore,,ex-situ X-ray photoelectron spectroscopy(XPS)/Raman/X-ray diffraction(XRD)and related electrochemical measurements reveal the SiOx core and Si of M-Li-SiOx participate in the lithiation,and pre-generated Li2Si20s with u+diffusivity and pomegranate-like.structure reduces the reaction resistance and interface impedance of the solid electrolyte interphase(SEI)film.

Comparison of Three External Wet Compress Methods in The Treatment of Facial Hormone Dependent Dermatitis

Objective:To compare the therapeutic effects of three different external wet compress methods on facial hormone dependent dermatitis(FCAD),and to provide reference for clinical treatment of FCAD.Methods:From June 2016 to June 2019,160 FCAD patients in our dermatology clinic were selected and divided into three groups according to random number table:the first group was treated with Compound Cortex Phellodendri liquid coating,the second group was treated with collagen paste dressing,and the third group was treated with 0.9%sodium chloride injection solution.Apply 8 layers of gauze or cold compress directly to the skin lesions for 4 weeks in each group.Results:After 4 weeks of treatment,no adverse reactions were found.The effective rates of the first group,the second group,and the third group were 72.22%,62.26%and 41.51%,respectively.Compared with the third group,the effective rate of the first group and the second group was significantly higher,and there was statistical significance between the groups(x2=10.294,x2=4.573,P<0.05);but there was no significant statistical difference between the first group and the second group(x2=1.205,P>0.05).Conclusion:Compound Cortex Phellodendri coating is suitable for FCAD patients with severe inflammation,collagen paste dressing is suitable for FCAD patients with mild to moderate inflammatory reaction and pigmentation,and 0.9%sodium chloride injection is suitable for patients with mild facial flushing and swelling.Clinical treatment should be selected according to the patient's condition and rash characteristics.