Ning Wu,Hao Guo,Liping Peng,Mingyue Wang,Yujuan Cao,Meng Yang,Lei Sun,Wu Yang
Thiodiglycolic acid (TDGA) is regarded as a sensitive biomarker for biological monitoring of VCM exposure. A simple, fast and reliable TDGA analysis method is of great significance to human health and the ecological environment. In this work, a novel core-shell nanomaterial based on p-type semiconductor@MOFs (Eu-CBO@Uio-66) is first prepared by in-situ growth and post-synthesis modification (PSM) as a ratiometric fluorescent probe for detecting TDGA, which shows a high sensitivity with a detection limit down to 51.1 μg L −1 (about 0.34 μM), relatively broad linear range (0–700 mg/L), fast response to TDGA within 2 min. As a result, after dispersing the resulting composite material in a solution containing TDGA, the blue emission of Eu-CBO@Uio-66 at 466 nm remains unchanged, while the red emission of Eu 3+ center at 615 nm is significantly quenched, even in coexistence with other potentially analytes in the urine, so that the peak height ratio of the two emissions could be employed for determining TDGA. In addition, the significant ratiometric luminescence response caused by TDGA makes Eu-CBO@Uio-66 undergo a significant color transition from red to blue under UV-lamp, which is beneficial for visual analysis with the naked eye.
Lichun Li,Xiaoli Wei,Shenglan Zhou,Zhongsheng Jia,Chuanzhao Wang,Houlin Yu,Sen Wu,Ying Li,Wenfeng Han
Hydrochlorofluorocarbon (HCFC) has been widely applied as the third-generation refrigerant globally, however, the global warming potential of such gases is often 100 and 1000 times higher than that of CO2. Dehydrochlorination reaction offers an encouraging strategy to transform the high-global-warming-potential gases of hydrochlorofluorocarbons (HCFCs) to low-global-warming-potential gases of hydrofluoroolefins (HFOs). However, the handling of a large amount of byproduct HCl remains one of the major challenges blocking the industrialization of dehydrochlorination of HCFC-142a for the production of vinylidene fluoride (VDF). A one-pot cascade reaction combining dehydrochlorination of HCFC-142b and hydrochlorination of acetylene was first proposed to spontaneously produce valuable monomers of VDF and vinyl chloride monomer (VCM) while eliminating the tedious HCl treatment step. Both thermodynamic calculations and experimental results validate the feasibility of the cascade reaction. Five different heterogeneous catalysts were screened for the proposed cascade reaction, including monocomponent catalyst BaF2, NAC, bifunctional BaF2/NAC catalyst, and bicomponent BaF2-NAC-S and BaF2-NAC-M catalysts. Among them, the mixed BaF2-NAC-M catalyst demonstrated the best catalytic performance, with BaF2 mainly acting as the dehydrochlorination site and NAC mainly acting as the hydrochlorination site. The corresponding reaction mechanism was also proposed.
危险品化学品经营许可证（带存储）