Phase diagram of the Fe-rich portion of R-Fe-Al pseudoternary system(R=Dy_(0.65)Tb_(0.25)Pr_(0.1))

The 1000℃ isothermal section of the Fe-rich portion of R-Fe-Al(R=Dy0.65Tb0.25Pr0.1) pseudoternary system has been investigated using optical microscopy,X-ray diffraction,EPMA and DTA techniques.The 1000℃ isothermal section consists of 9 single-phase regions,14 two-phase regions and 6 three-phase regions.In the R-Fe pseudobinary system,except the R2Fe17 compound,the homogeneity regions of other compounds are shifted towards the stoichiometric rare earth-rich side.With Fe partially substituted by Al,the homogeneity region of R(Fe1-xAlx)2 is shifted back to the stoichiometric composition when x=0.15 and remains little changed with 0.15≤x≤0.30.The homogeneity regions of R(Fe1-xAlx)3 and R6(Fe1-xAlx)23 are slightly shifted to the stoichiometric rare earth-rich side with increasing Al content.A vertical section along R=33.33 atomic percentage is also investigated.It consists of 2 single-phase regions,4 two-phase regions and 2 three-phase regions.

Establishment and evaluation of O/W type-based microemulsion on crossbow medicine of the Miao ethnic group

Background:Crossbow medicine needle is a traditional external therapy.However,acupuncture pain,inaccurate administration,secondary infection,and poor patient compliance limit the application of specialty therapies.Since the most effective components of crossbow medicine are lipid-soluble,the crossbow medicine needle was prepared as an innovative O/W-type microemulsion to solve these problems.In this study,the crossbow medicine microemulsion preparation method was established and its quality was evaluated.Methods:A single factor and pseudoternary phase diagram,combined with a D-optimal mixture design,optimized the formulation of crossbow medicine microemulsion through particle size,polydispersity index,zeta potential,microstructure,and contents of benzoyl neoaconitine,benzoyl hypoaconitine,neoaconitine,periplocin,and methyl salicylate to evaluate the final prescription.Results:The best prescription for preparing crossbow medicine microemulsion is 0.1500 g crossbow medicine dry extract,0.1500 g isopropyl myristate,0.8625 g polyoxyethylene castor oil-35,0.2875 g ethanol,3.700 g water,and 5.1500 g microemulsion.The prepared microemulsion is an oil-in-water type with a clear and transparent appearance.Its average particle size is 19.83±0.78 nm,average polydispersity index is 0.15±0.02,and average zeta potential is−0.51±0.1 mV.The pH value is 5.17±0.02.The microstructure of crossbow medicine microemulsion illustrated a uniform distribution of spherical oil globules.The average contents of benzoyl neoaconitine,benzoyl hypoaconitine,neoaconitine,periplocin,and methyl salicylate were 13.34,113.05,43.45,628.27 and 27.93μg/g,respectively.Conclusion:The preparation process of crossbow medicine microemulsion is reasonable and feasible.The method to determine the content is accurate and straightforward,laying the foundation for further research.

Investigation on crystallization behavior between(Sc_(x)Yb_(1−x))O_(1.5)and CMAS:A new insight in the effect of Sc substitution

Environmental barrier coatings(EBCs)with thermomechanical robustness against calcium–magnesium–aluminum–silicate(CMAS)deposits are in high demand.The aim of this work was to clarify the influence of Sc^(3+)on the crystallization behavior of Yb-based coatings against CMAS deposits.The reaction products of solid solutions with compositions traversing the Sc_(2)O_(3)–Yb_(2)O_(3)system indicate that Sc^(3+)tends to form[BO_(6)]coordination polyhedra in the crystal structure to promote the formation of garnet and diopside,while Yb^(3+)occupies 7-,8-,and 9-coordinate sites to crystallize apatite and silicocarnotite.The transformation of crystalline products from apatite/silicocarnotite to garnet/diopside greatly improves the efficiency of CMAS melt consumption and facilitates the prevention of its further penetration and corrosion.Based on the commonality of cation occupancy in crystallography,an A(CaO+YbO_(1.5))–B(ScO_(1.5)+MgO+AlO_(1.5))–T(SiO_(2))pseudoternary phase diagram is established,which has great potential for describing phase equilibrium in coating-deposit systems and can provide guidance for the compositional design of corrosion-resistant coatings.