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The crown ether strontium extraction (CESE) process has been developed for the recovery or removal of Sr from acidic high-level liquid waste (HLLW) in China, where the extractant is 4',4"(5")-di-(tert-butyldicyclohexano)-18-crown-6 (DtBuCH18C6) and the diluent is n-octanol. When the CESE process was operated in annular centrifugal extractors (ACEs) for demonstration by cold and hot tests, it was found that the outlet aqueous phases had organic-phase entrainment even though ACEs operated at a low rotor speed. For the successful operation of the CESE process in ACEs, effects of the operating and geometrical parameters on the liquid hold-up volume and phase ratio (aqueous phase/organic phase, A/O) of the HNO3–DtBuCH18C6/n-octanol system in a ϕ20 ACE were systematically investigated to find the cause of the above-mentioned hydrodynamic performance problem of the CESE process using the liquid-fast-separation method. It is shown that the operating and geometrical parameters have effects on the liquid hold-up volume and phase ratio (A/O). Moreover, the phase ratio (A/O) in the separation zone of the rotor is less than 1.5 under most of the present experimental conditions, which shows organic-phase entrainment may easily occur in the outlet aqueous phase. The cause can be that the density difference of two phases is small, viscosity of the organic phase is large, and interfacial tension of the extraction system is low. [ABSTRACT FROM AUTHOR]

Drug metabolism research plays an essential role in drug discovery and development. Great efforts have been made domestically to be line with the international standardized research on drug metabolism. In this article, we will review new-generation of tyrosine kinase inhibitors(TKIs), these TKIs include icotinib, apatinib, famitinib, flumatinb, allitinib, fruquintinib, and selatinib, among which icotinib and apatinib have been approved by China food and drug administration(CFDA) to reach the market, while others are in clinical trials. For these TKIs, the structural modified sites are active metabolic centers and CYP3A4 is identified as the primary metabolic enzyme. Considering the active intermediates, the crown ether ring of icotinib is oxidated to open to form an aldehyde; the indolylidene ring of famitinib is oxidated followed by rearrangement to form a quinone- imine; the α, β-unsaturated carbonyl group of allitinib is oxidated to form an epoxide, these intermediates are capable of covalently binding biomolecules and generating toxicity. In addition, human (14)C radioactive trials of most of these TKIs have not been conducted, and the data of drug-drug interactions in clinic are also absent, which indicate our deficiency compared to the international regular approaches in metabolic research.