1. Latest advances in the gaseous phase catalytic synthesis of difluoromethane and the preparation of catalysts are summarized.
   综述了二氟甲烷的气相催化合成工艺及其催化剂制备的最新进展;
2. Difluoromethane (CH2F2, HFC-32) is considered as the most important alternative to HCFC-22, by mixing with other HFCs.
   二氟甲烷(CH2F2, HFC-32)与其它HFC物质的混合工质是国际上公认的HCFC-22最有希望的替代物；

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