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To investigate the effects of ordinary PE packaging (CK) and physically active packaging (PA) on post-harvest storage quality, respiratory metabolism, and energy metabolism of Lentinula edodes, L. edodes '808' was used as experimental material, and stored at (4±1) ℃ and 90%±5% relative humidity for 12 d. The sensory evaluation, weight loss, hardness, total soluble solids, soluble protein, respiration rate, key enzyme activities in respiration and energy metabolism, energy substance, and energy charge of L. edodes were measured every 3 d. The results showed that PA treatment delayed the deterioration of the sensory quality of L. edodes, inhibited the increase of the weight loss rate, retarded the decline of the hardness, total soluble solids, and soluble proteins, reduced the respiratory intensity, and postponed the emergence of L. edodes respiratory peaks. Further research indicated that L. edodes under PA treatment were able to maintain higher levels of cytochrome C oxidase (CCO) and malate dehydrogenase (MDH) enzyme activities while inhibiting the rapid increase in glucose-6-phosphate isomerase (PGI), succinate dehydrogenase (SDH) and pyruvate dehydrogenase (PDH) enzyme activities. Meanwhile, PA treatment also suppressed the degradation of ATP and ADP in L. edodes, and maintained a high level of energy charge. The correlation analysis revealed that the sensory quality of L. edodes was a highly significantly positive correlation with hardness, total soluble solids, MDH, ATP, and energy charge (P

The porosities of the Lower Cambrian shale and Upper Ordovician-Lower Silurian marine shale from the Sichuan Basin were analyzed using He-Hg porosimetry and field-emission scanning electron microscopy, to discuss the relationship of porosity to the organic matter maturity, total organic carbon (TOC) and free gas volume. Overmature (Ro greater than 2%) shale samples with a TOC less than 5% display a positive correlation between TOC and porosity, but samples with a TOC greater than 5% display a limited increase in porosity with increasing TOC. The porosity of shale decreases generally with increasing maturity in the overmature stage. The free gas in porosity is the key factor for successful development of shale gas, and free gas volumes are controlled by porosity and gas saturation. Higher TOC shale has higher porosity and gas saturation. The Lower Silurian Longmaxi Formation shale has a higher TOC, Ro ranging from 2.0% to 2.3%, its porosity and gas saturation are significantly higher than the Lower Cambrian shale. The high free gas volume results in high production in the Lower Silurian Longmaxi Formation shale pay. Key words: marine shale, porosity, free gas, overmature, Sichuan Basin