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This is an article in the field of metallurgical engineering. In this article, TiH2 powder was selected as the experimental raw material to study the sintering behavior of TiH2 powder under different pressing pressure and holding time in cold isostatic pressing, to reveal the effects of pressing pressure and holding time on the shrinkage as well as the relative density of TiH2 sintered specimens, in order to improve the density of the billet and the performance of the products. The results show that the shrinkage of the sintered sample decreases with the increase of the pressing pressure, and when the pressing pressure reaches 400 MPa, the pressing pressure has little effect on the relative density of the sintered sample. For the consideration of the sample preparation efficiency and the pressing pressure limit of the cold isostatic press, the pressing pressure should not exceed 400 Mpa. The shrinkage of sintered samples decreases with the increase of holding time, and when the holding time reaches 20 min, the relative density of sintered samples changes little with the extension of holding time. For the consideration of sample preparation efficiency, the suitable holding time is 15～20 min.

The volatile aroma compounds of wine fermented from goji berries were evaluated by liquid-liquid extraction-solvent-assisted evaporation-gas chromatography-mass spectrometry-olfactometry (LLE-SAFE-GC-MS-O) combined with GC-quadrupole-MS (GC-qMS) and GC-Orbitrap-MS. The key aroma compounds were identified by aroma reconstitution and quantitative descriptive sensory analysis. The results showed that ethyl esters (ethyl cinnamate, ethyl acetate, ethyl 2-methylpropanoate, ethyl 2-methylbutanoate, ethyl 3-methylbutanoate, ethyl hexanoate, ethyl lactate, ethyl octanoate, and ethyl decanoate), other esters (isoamyl acetate and isoamyl lactate), C13-norisoprenoids (β-damascenone and β-ionone), volatile phenols (4-ethylguaiacol, eugenol, 2,4-di-t-butylphenol), alcohols (1-octen-3-ol, benzyl alcohol, phenylethyl alcohol and isopentyl alcohol) and other compounds (naphthalene, methionol, octanoic acid and 2-acetylpyrrole) contributed the major aroma attributes of goji berry wine. This finding will help to enrich and improve the theoretical basis of the aroma of goji berry wine and lay the foundation for aroma enhancement and quality improvement of goji berry wine.