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A 9-week feeding trial was conducted to investigate the effects of different dietary sources of astaxanthin on fillet coloration, texture, and nutrient composition in rainbow trout (Oncorhynchus mykiss). Eight diets were formulated to contain 0, 25, 50, 75, 100, and 125 mg/kg astaxanthin from wall-broken Haematococcus pluvialis (WBHPA), 100 mg/kg astaxanthin from wall-unbroken H. pluvialis (WUHPA), or chemically synthesized astaxanthin (CSA). Each diet was fed to triplicate groups of rainbow trout (mean initial weight of 561 g) twice daily (07:00 and 17:00) to apparent satiation for 9 weeks. Results showed that at the 100 mg/kg astaxanthin inclusion level, the CAS group had higher fillet gross energy, dorsal fillet redness, and dorsal fillet color card score compared to the WBHPA-100 group, with both being higher than the WUHPA group (P < 0.05). Fillet astaxanthin content, dorsal fillet yellowness, and lateral line redness and yellowness did not differ significantly between the CSA and WBHPA-100 groups (P > 0.05), but were higher than the WUHPA group. When WBHPA was used, the inclusion of 50–100 mg/kg decreased fillet lightness but increased fillet redness, while better fillet texture was served at 75–125 mg/kg. Dietary 25–125 mg/kg WBHPA inclusion increased fillet astaxanthin and gross energy concentrations, with minor effects on fatty acid compositions of fillet. Inclusion of over 100 mg/kg astaxanthin regardless of source decreased fillet threonine and serine contents, and the WBHPA-100 group had lower fillet glycine and alanine contents compared to the control group (P < 0.05). In conclusion, CSA had the most significant impact on fillet coloration and energy deposition in rainbow trout, while WUHPA had the least favorable effect. Additionally, the wall-breaking treatment of H. pluvialis can improve the effect of astaxanthin on fillet coloration and nutrient composition in rainbow trout, with a recommended dose range of 75–100 mg/kg. [ABSTRACT FROM AUTHOR]

MgO-Al2 O3-SiO2 (MAS) glass-ceramics were prepared by sintering method. The effects of different Al2 O3/SiO2 mass ratios on the microstructure and physicochemical properties of MAS glass-ceramics were studied. The structure and surface morphology of parent glass and glass-ceramics were characterized by XRD, DSC, FTIR and FESEM. The density, mechanical properties, corrosion resistance, thermal properties and dielectric properties of glass-ceramics were tested. The results show that as the mass ratio of Al2 O3/SiO2 increases from 0.52 to 0.64, the glass transition temperature Tg of the parent glass increases and the crystallization peak temperature Tp of the parent glass decreases, promoting the precipitation of α-cordierite crystal phase. The density of the samples fluctuates in the range of 2.52 ~increases from 1.73 to 4.51, thermal expansion coefficient decreases from 4.46 x10-6 to 2.38 x10-6°C-1, dielectric loss tan δ fluctuates in the range of 8.4 x 10-3 ~ 3.7 x 10-3, and the flexural strength fluctuates in the range of 80 ~120 MPa. [ABSTRACT FROM AUTHOR]

In this work, CaO-MgO-Al2O3-SiO2 (CMAS) system alkali-free aluminosilicate glass was selected as the research object. Eight groups of Fe2O3 component variables were designed, and the experimental samples were prepared by high temperature melting method. XRD, SEM, TG-DSC and other test methods were used to tested and analyzed the phase, crystallization kinetics, crystallization behavior and elastic modulus of alkali-free glass samples, and then the effects of Fe2O3 content and crystallization treatment on the elastic modulus of alkali-free glass were discussed. The results show that the appropriate addition of Fe2O3 improves the elastic modulus of CMAS system alkali-free glass. When the mass fraction of Fe2O3 is 1.50% (F-6 #), the maximum elastic modulus of F-6 # alkali-free glass is 97.87 GPa, the crystallization activation energy is 347.1 kJ/ mol, and the crystallization index n is 1.383 4, which is surface crystallization. After crystallization treatment by bulk crystallization method, the main crystalline phase precipitated from F-6# glass-ceramics is anorthite phase (CaAl2Si2O8), and the crystal size is 200 ~400 nm. After crystallization treatment by sintering method, the main crystalline phase precipitated from F-6# glass-ceramics is anorthite phase (CaAl2Si2O8), and the crystal size is 300 ~ 500 nm. With the increase of heat treatment temperature, the number and size of the precipitated main crystal phase increase, but the type of the main crystalline phase keeps unchanged. However, because the elastic modulus of anorthite is smaller than that of the base glass, the elastic modulus of the glass-ceramics obtained after crystallization of F-6# alkali-free glass decreases. [ABSTRACT FROM AUTHOR]