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Hydrogen isotopes have extremely important roles in many fields, but they have almost the same chemical and similar physical properties, which makes the separation process very difficult. In this work, ZIF-67 was selected for the separation of hydrogen isotopes. The theoretical calculation results showed that the adsorption selectivity of ZIF-67 for hydrogen isotope mixtures (D 2 /H 2 = 1:1) increased from 1.66 to 2.08 with the temperature decreasing from 77 to 20 K, indicating that ZIF-67 has a chemical affinity quantum sieving (CAQS) effect. Meanwhile, the diffusion coefficients of H 2 and D 2 were also different; the kinetic selectivity of D 2 /H 2 was 4.41 at 70 K, indicating that ZIF-67 has a kinetic quantum sieving (KQS) effect at low temperatures. When the temperature was higher than 72 K, the diffusion coefficient of H 2 was higher than that of D 2 ; ZIF-67 showed a typical kinetic sieving effect and the kinetic selectivity of H 2 /D 2 was 1.29 at 77 K. Based on the fact that due to the CAQS effect, the adsorption capacity of D 2 in ZIF-67 was higher at 77 K and the diffusion coefficient of D 2 was lower at the same time, it is expected that ZIF-67 can effectively realize the separation of hydrogen isotopes. In contrast, ZIF-8, isostructural to ZIF-67, has no difference on H 2 and D 2 in view of adsorption capacity and adsorption heat and, consequently, has no effect on separation, indicating the importance of the incompletely filled d-orbitals (Co 2+ versus Zn 2+ ). To verify the separation performance of ZIF-67, the composites ZIF-67@NH 2 -γ-Al 2 O 3 were synthesized by the layer-by-layer (LBL) method and used as a gas chromatographic stationary phase packed in a 1 m column (1.0 m × 2.0 mm I.D.) for separation of hydrogen isotopes H 2 and D 2 . Under optimal chromatographic separation conditions, the resolution (R) reached 1.79 and the separation time was 5.55 min with the optimal composite ZIF-67@NH 2 -γ-Al 2 O 3 at 77 K.

The present study describes the improved mycelia and exo-polymer production under control of Grifola frondosa morphology by changing the aeration rate and agitation intensity in a 25-L stirred fermentor. The aeration rate of 1.0 vvm yielded a highest mycelia biomass of 24.754 g/L with the lowest pellet percentage of 20.5 %. The maximum exo-polymer (2.324 g/L) was achieved at 0.75 vvm with mycelia polysaccharide production (0.321 g/g), whereas clumps and filaments dominated the ratios of 45.6 and 33.9 %, respectively. The change of aeration rate and agitation intensity had slight influence on the monosaccharide compositions in exo-polymers and significantly affected glucose and mannose contents in the mycelia polysaccharides. These findings will provide a clue for exploring the relationship between fermentation parameters, morphologies, and polysaccharide synthesis pathway of G. frondosa.