Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a ...Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a hydrothermal method.The HDO performance of the catalysts was evaluated using 4-ethylguaiacol as a model compound at 340℃ under 3 MPa H2.The MoS_(2)/NC catalyst exhibited a deoxygenation degree of 83.4%,whereas the Fe-modified catalyst(Fe_(0.3)MoS/NC)attained complete deoxygenation(100%)with an arenes selectivity of 78.6%.Beyond the optimal ratio,the deoxygenation degree is inversely proportional to the Fe/Mo molar ratio.The catalysts were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),low-temperature nitrogen adsorption(BET method)and X-ray photoelectron spectroscopy(XPS).The characterization results indicated that the introduction of Fe enhanced the uniform dispersion of MoS_(2)on the NC support surface.This modification further increased the acidity of the catalyst surface and raised the concentration of sulfur vacancies,thereby promoting the adsorption of oxygencontaining compounds.Furthermore,the HDO performance of the Fe_(0.3)MoS/NC catalyst was evaluated using actual lignin as a feedstock under the conditions of 340℃,3 MPa H2 and 12 h.The results showed a green hydrocarbon yield of 65.5%,of which the C_(8)-C_(16)fraction accounted for 54.4%of the total hydrocarbons.Within this fraction,aromatic compounds constituted 63.4%,suggesting its potential use as green aviation fuel-range arenes.This work thus establishes a viable catalytic pathway for efficient conversion of lignin to arenes.展开更多
基金Supported by grants from National Key Research and Development Program of China(2024YFB4205903)the National Natural Science Foundation of China(52274308,U22B20144,22278440 and 22078362)Shandong Provincial Technology Innovation Guidance Plan(YDZX2023060)。
文摘Lignin contains abundant aromatic ring structures,which can be converted into green sustainable aviation fuelrange arenes through hydrodeoxygenation(HDO).A series of supported FeMoS/NC catalysts were synthesized by a hydrothermal method.The HDO performance of the catalysts was evaluated using 4-ethylguaiacol as a model compound at 340℃ under 3 MPa H2.The MoS_(2)/NC catalyst exhibited a deoxygenation degree of 83.4%,whereas the Fe-modified catalyst(Fe_(0.3)MoS/NC)attained complete deoxygenation(100%)with an arenes selectivity of 78.6%.Beyond the optimal ratio,the deoxygenation degree is inversely proportional to the Fe/Mo molar ratio.The catalysts were characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),low-temperature nitrogen adsorption(BET method)and X-ray photoelectron spectroscopy(XPS).The characterization results indicated that the introduction of Fe enhanced the uniform dispersion of MoS_(2)on the NC support surface.This modification further increased the acidity of the catalyst surface and raised the concentration of sulfur vacancies,thereby promoting the adsorption of oxygencontaining compounds.Furthermore,the HDO performance of the Fe_(0.3)MoS/NC catalyst was evaluated using actual lignin as a feedstock under the conditions of 340℃,3 MPa H2 and 12 h.The results showed a green hydrocarbon yield of 65.5%,of which the C_(8)-C_(16)fraction accounted for 54.4%of the total hydrocarbons.Within this fraction,aromatic compounds constituted 63.4%,suggesting its potential use as green aviation fuel-range arenes.This work thus establishes a viable catalytic pathway for efficient conversion of lignin to arenes.
文摘目的探讨MR磁敏感加权成像(susceptibility-weighted imaging,SWI)在鉴别BosniakⅡF~Ⅲ级肾脏囊性病变(cystic renal masses,CRMs)良恶性中的应用价值。材料与方法回顾性分析38例BosniakⅡF~Ⅲ级CRMs患者的影像特征,以病理诊断作为金标准分为良性组(17例)、恶性组(21例)。观察两组病变的T1WI、T2WI及SWI图像,记录病变大小、形状、T1WI与T2WI图像上病变囊腔信号及瘤内磁敏感信号(intratumoral susceptibility signal intensity,ITSS)评价情况(包括ITSS主要结构、出血灶数目、微血管数目及实性成分中ITSS所占面积比)。利用卡方检验比较两组病变T1WI、T2WI囊腔信号差异;以Mann-Whitney U检验比较两组病变ITSS显示情况的差异;以Kappa检验比较两位观察者评级一致性;利用二元logistic回归分析构建ITSS评价指标联合预测因子;受试者工作特征(receiver operating characteristic,ROC)曲线分析不同ITSS评价指标及联合预测因子鉴别良恶性病变的诊断效能,DeLong检验比较曲线下面积(area under the curve,AUC)差异。结果BosniakⅡF~Ⅲ级肾脏囊性病变在T1WI、T2WI上的信号在良恶性组中的差异无统计学意义(P>0.05)。良性组的ITSS主要结构评级高于恶性组,但二者差异无统计学意义(P>0.05)。恶性组中出血灶数目、微血管数目及实性成分中ITSS所占面积比评级均高于良性组,且二者差异具有统计学意义(P<0.01)。两位观察者对良恶性组病变ITSS主要结构及实性成分中ITSS所占面积比评价结果一致性较好(Kappa值为0.72和0.74),对出血灶数目、微血管数目的评价结果很好(Kappa值为0.90和0.84)。出血灶数目、微血管数目、实性成分中ITSS所占面积比及联合预测因子鉴别BosniakⅡF~Ⅲ级CRMs良恶性的AUC分别为0.695[95%置信区间(confidenceinterval,CI):0.520~0.869]、0.868(95%CI:0.757~0.980)、0.877(95%CI:0.771~0.983)和0.943(95%CI:0.877~1.000)。DeLong检验结果显示,联合预测因子的诊断效能优于单一ITSS评价指标,差异有统计学意义(P=0.02、P<0.01、P<0.01)结论通过对SWI图像上磁敏感信号的分析,能够为鉴别BosniakⅡF~Ⅲ级CRMs的良恶性提供有价值的信息,为临床诊疗提供可靠的影像依据。
