| 1 | Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) emissions from electric arc furnaces for steelmaking显示文摘The proportion of steel produced using electric arc furnaces(EAFs)is increasing.In this study,polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs)concentrations and patterns in stack gas samples from three typical EAFs in steelmaking plants were determined to allow the contributions of EAFs in steelmaking plants to PCDD/Fs emissions in China to be assessed.Samples collection was accomplished by adopting the automatic isokinetic sampling technique,then the PCDD/Fs congeners concentrations were analyzed qualitatively and quantitatively by isotope dilution high-resolution gas chromatography high-resolution mass spectrometry(HRGC-HRMS).The mean PCDD/Fs mass concentrations in stack gases emitted during the scrap preheating phase of plants E1,E2,and E3 were 0.48,385.55,and 0.34 ng Nm^-3,respectively,and the total toxic equivalent(WHO2005-TEQ)concentrations were 0.05,33.16,and 0.03 ng Nm^-3,respectively.The PCDD/Fs mass concentration in stack gases emitted during the melting phase at plant E3 was 0.12 ng Nm^-3(0.02 ng WHO2005-TEQ Nm^-3).The operational temperature of the bag filter of the preheating in the E2 EAF was as high as 230℃,which is conducive to the generation of PCDD/Fs,whether the temperature in the bag filter of E1(150℃)and E3(120℃)are not.Moreover,the bag filter temperature is suggested to be best controlled to below 150℃.The emission factors(EF)for PCDD/Fs released into the air during the scrap preheating phase for plants E1,E2,and E3 were 0.13,52,and 0.10 mg WHO2005-TEQ t1,respectively,and the EF for the smelting phase from plant E3 was 0.14 mg WHO2005-TEQ t1.The emission factor in E2 is 5 times higher than the highest current UNEP toolkit factor for EAFs(10 mg TEQ/tonne steel).Therefore,an update for the UNEP toolkit emission factor for a few case plants is suggested.Several congeners,including 2,3,7,8-TeCDF,1,2,3,4,6,7,8-HpCDF,and 1,2,3,4,6,7,8-HpCDD,were dominant during the preheating phase,while 2,3,7,8-TeCDF,1,2,3,7,8-PeCDF,and 2,3,4,7,8-PeCDF were dominant during the smelting phase.The monitoring data from the case plants helps to better understand the PCDD/Fs emissions of EAFs using preheating process stages.However,a more complete emission inventory requires more case investigations on the PCDD/Fs emissions from representative EAFs steelmaking plants. | Qiuting Yang Lili Yang Jia Shen Yuanping Yang Minxiang Wang Xiaoyun Liu Xuejing Shen Changliang Li Jia Xu Fengfeng Li Da Li Guorui Liu Minghui Zheng | 2020 | Emerging Contaminants2020,6,1: | 3 |
| 2 | Hymecromone:a clinical prescription hyaluronan inhibitor for efficiently blocking COVID-19 progression显示文摘Currently,there is no effective drugs for treating clinically COVID-19 except dexamethasone.We previously revealed that human identical sequences of SARS-CoV-2 promote the COVID-19 progression by upregulating hyaluronic acid(HA).As the inhibitor of HA synthesis,hymecromone is an approved prescription drug used for treating biliary spasm.Here,we aimed to investigate the relation between HA and COVID-19,and evaluate the therapeutic effects of hymecromone on COVID-19.Firstly,HA was closely relevant to clinical parameters,including lymphocytes(n=158;r=−0.50;P<0.0001),C-reactive protein(n=156;r=0.55;P<0.0001),D-dimer(n=154;r=0.38;P<0.0001),and fibrinogen(n=152;r=0.37;P<0.0001),as well as the mass(n=78;r=0.43;P<0.0001)and volume(n=78;r=0.41;P=0.0002)of ground-glass opacity,the mass(n=78;r=0.48;P<0.0001)and volume(n=78;r=0.47;P<0.0001)of consolidation in patient with low level of hyaluronan(HA<48.43 ng/mL).Furthermore,hyaluronan could directly cause mouse pulmonary lesions.Besides,hymecromone remarkably reduced HA via downregulating HAS2/HAS3 expression.Moreover,89%patients with hymecromone treatment had pulmonary lesion absorption while only 42%patients in control group had pulmonary lesion absorption(P<0.0001).In addition,lymphocytes recovered more quickly in hymecromone-treated patients(n=8)than control group(n=5)(P<0.05).These findings suggest that hymecromone is a promising drug for COVID-19 and deserves our further efforts to determine its effect in a larger cohort. | Shuai Yang Yun Ling Fang Zhao Wei Li Zhigang Song Lu Wang Qiuting Li Mengxing Liu Ying Tong Lu Chen Daoping Ru Tongsheng Zhang Kaicheng Zhou Baolong Zhang Peng Xu Zhicong Yang Wenxuan Li Yuanlin Song Jianqing Xu Tongyu Zhu Fei Shan Wenqiang Yu Hongzhou Lu | 2022 | Signal Transduction and Targeted Therapy2022,7,4: | 2 |