In this study,different loadings of x%Ni_(2)P/γ-Al_(2)O_(3)(x=6%,9%,12%,15%,18%)catalysts with aluminum oxide(Al_(2)O_(3))as the carrier,nickel chloride(NiCl2)as the nickel(Ni)source,and ammonium hypophosphite(NH_(4)...In this study,different loadings of x%Ni_(2)P/γ-Al_(2)O_(3)(x=6%,9%,12%,15%,18%)catalysts with aluminum oxide(Al_(2)O_(3))as the carrier,nickel chloride(NiCl2)as the nickel(Ni)source,and ammonium hypophosphite(NH_(4)H_(2)PO_(2))as the phosphorus(P)source were prepared by the equal volume impregnation method to investigate the effects of different loadings on the performance of the selective hydrogenation of diolefins and thiol etherification in LPG.The physicochemical properties of the catalysts were characterized by XRD,BET,SEM,TEM,H_(2)-TPR,and XPS,and the catalytic activity of the catalysts was evaluated in a fixed-bed microreactor.The results showed that a change in the loading affected the catalyst crystalline phase structure and size,specific surface area,P coverage,active phase dispersion,and catalytic activity.At 6%,9%,and 12%loadings the catalysts had an Ni phase but there was no obvious Ni_(2)P phase in the nickel phosphide;at 15%loading a single Ni_(2)P phase was obtained,and at 18%loading both Ni_(2)P and Ni1_(2)P_(5) phases appeared.There was a P enrichment on the catalyst surface,and the higher the loading the more P species were enriched on the surface,but some of the P was lost during the catalyst reduction process due to the production of phosphine(PH3)gas.The 15%Ni_(2)P/γ-Al_(2)O_(3) catalyst had the largest Ni/Al ratio and the best dispersion.The Ni_(2)P active phase size was small at about 4.25 nm and Ni_(2)P was uniformly dispersed on the catalyst surface without agglomeration.The 15%Ni_(2)P/γ-Al_(2)O_(3) catalyst had the best catalytic activity at a pressure of 2.0 MPa,a liquid hourly space velocity(LHSV)of 3.0 h-1,and a hydrogen to hydrocarbon ratio of 12.The 1,3-butadiene conversion was 97.45%and the methanethiol removal was 100%at a temperature of 140℃.展开更多
目的:研究Ⅱ~Ⅳ期胰腺癌患者经重离子放疗或放疗联合化疗的MRI影像学资料,以评估疗效。方法:回顾性分析我院收治的经碳离子治疗的49例Ⅱ~Ⅳ期胰腺癌患者的肿瘤轴位面积及DWI弥散加权成像中的ADC值,以治疗前数值为基线,与治疗后第1个月及...目的:研究Ⅱ~Ⅳ期胰腺癌患者经重离子放疗或放疗联合化疗的MRI影像学资料,以评估疗效。方法:回顾性分析我院收治的经碳离子治疗的49例Ⅱ~Ⅳ期胰腺癌患者的肿瘤轴位面积及DWI弥散加权成像中的ADC值,以治疗前数值为基线,与治疗后第1个月及第3~7个月复查时的肿瘤轴位面积及ADC值进行对比。结果:在重离子放疗后第1个月复查,瘤灶面积较治疗前明显缩小,差异有统计学意义(P<0.05);分析了11例患者治疗后第3~7个月复查的轴位面积,发现瘤灶面积较治疗后第1月复查缩小(P=0.01);而重离子放疗后第1个月复查,与治疗前肿瘤ADC值相比明显升高(P<0.01)。胰腺癌经碳离子治疗前后病灶面积与ADC值的ROC曲线显示,病灶面积基线期与治疗后1个月、治疗后3~7月比较,AUC分别为0.567、0.858,提示用第3~7个月时复查瘤灶面积缩小预测重离子放疗胰腺癌有效的准确率更高。结论:重离子放疗联合化疗或单独使用治疗不能手术中晚期胰腺癌患者,初期复查疗效显著,3.0 T MRI可对重离子治疗胰腺癌患者进行疗效评估。展开更多
文摘In this study,different loadings of x%Ni_(2)P/γ-Al_(2)O_(3)(x=6%,9%,12%,15%,18%)catalysts with aluminum oxide(Al_(2)O_(3))as the carrier,nickel chloride(NiCl2)as the nickel(Ni)source,and ammonium hypophosphite(NH_(4)H_(2)PO_(2))as the phosphorus(P)source were prepared by the equal volume impregnation method to investigate the effects of different loadings on the performance of the selective hydrogenation of diolefins and thiol etherification in LPG.The physicochemical properties of the catalysts were characterized by XRD,BET,SEM,TEM,H_(2)-TPR,and XPS,and the catalytic activity of the catalysts was evaluated in a fixed-bed microreactor.The results showed that a change in the loading affected the catalyst crystalline phase structure and size,specific surface area,P coverage,active phase dispersion,and catalytic activity.At 6%,9%,and 12%loadings the catalysts had an Ni phase but there was no obvious Ni_(2)P phase in the nickel phosphide;at 15%loading a single Ni_(2)P phase was obtained,and at 18%loading both Ni_(2)P and Ni1_(2)P_(5) phases appeared.There was a P enrichment on the catalyst surface,and the higher the loading the more P species were enriched on the surface,but some of the P was lost during the catalyst reduction process due to the production of phosphine(PH3)gas.The 15%Ni_(2)P/γ-Al_(2)O_(3) catalyst had the largest Ni/Al ratio and the best dispersion.The Ni_(2)P active phase size was small at about 4.25 nm and Ni_(2)P was uniformly dispersed on the catalyst surface without agglomeration.The 15%Ni_(2)P/γ-Al_(2)O_(3) catalyst had the best catalytic activity at a pressure of 2.0 MPa,a liquid hourly space velocity(LHSV)of 3.0 h-1,and a hydrogen to hydrocarbon ratio of 12.The 1,3-butadiene conversion was 97.45%and the methanethiol removal was 100%at a temperature of 140℃.
文摘目的:研究Ⅱ~Ⅳ期胰腺癌患者经重离子放疗或放疗联合化疗的MRI影像学资料,以评估疗效。方法:回顾性分析我院收治的经碳离子治疗的49例Ⅱ~Ⅳ期胰腺癌患者的肿瘤轴位面积及DWI弥散加权成像中的ADC值,以治疗前数值为基线,与治疗后第1个月及第3~7个月复查时的肿瘤轴位面积及ADC值进行对比。结果:在重离子放疗后第1个月复查,瘤灶面积较治疗前明显缩小,差异有统计学意义(P<0.05);分析了11例患者治疗后第3~7个月复查的轴位面积,发现瘤灶面积较治疗后第1月复查缩小(P=0.01);而重离子放疗后第1个月复查,与治疗前肿瘤ADC值相比明显升高(P<0.01)。胰腺癌经碳离子治疗前后病灶面积与ADC值的ROC曲线显示,病灶面积基线期与治疗后1个月、治疗后3~7月比较,AUC分别为0.567、0.858,提示用第3~7个月时复查瘤灶面积缩小预测重离子放疗胰腺癌有效的准确率更高。结论:重离子放疗联合化疗或单独使用治疗不能手术中晚期胰腺癌患者,初期复查疗效显著,3.0 T MRI可对重离子治疗胰腺癌患者进行疗效评估。
