Porous Pt thin films were prepared on carbon papers by a single-step ultra-high dc magnetron sputtering method to obtain ideal electrodes for proton exchange membrane fuel cells.The platinum loading of the electrocata...Porous Pt thin films were prepared on carbon papers by a single-step ultra-high dc magnetron sputtering method to obtain ideal electrodes for proton exchange membrane fuel cells.The platinum loading of the electrocatalyst layer is controlled at about 0.1 mg·cm^(-2).Structural characteristics and catalytic activities of the films were analyzed by scanning electron microscopy,atomic force microscopy,X-ray diffraction,cyclic voltammetry,and stress durability testing methods.The effect of treatment conditions of a substrate on the structural and performance characteristics of the catalytic films was shown as well.Films produced on acid-treated carbon papers at the argon pressure of 0.01 mbar possessed a homogeneous,highly developed surface along with a porous structure.Compared to Pt/TCPW(Toray carbon papers soaked in ultrapure water)electrodes,the film obtained on the acid-treated substrate had a larger electrochemical surface area(163.33 m^(2)·g^(-1))and exhibited better catalytic stability and durability due to a porous structure as a result of Pt particle accumulation.展开更多
目的探讨乳腺基底细胞型导管内原位癌的组织病理学形态、免疫组化及其诊断和鉴别诊断。方法对7例乳腺基底细胞型导管内原位癌患者的临床组织病理学和免疫组化特征进行观察,并复习相关文献。结果7例乳腺基底细胞型导管内原位癌,肿瘤长径0...目的探讨乳腺基底细胞型导管内原位癌的组织病理学形态、免疫组化及其诊断和鉴别诊断。方法对7例乳腺基底细胞型导管内原位癌患者的临床组织病理学和免疫组化特征进行观察,并复习相关文献。结果7例乳腺基底细胞型导管内原位癌,肿瘤长径0.8~3.8cm,镜下瘤细胞为实体型、乳头状或筛状型,可见点状坏死及中央坏死(粉刺型),筛状型的筛孔多呈圆形,腔缘光滑,细胞无极性分化。7例中免疫组化检测CK5/6(+)7例,CK14(+)、CK17(+)和P63(+)各6例、EGFR(+)5例、CD117(+)4例,Ki-67阳性(+30%~60%)。结论乳腺基底细胞型导管内原位癌是一种特殊类型的导管内原位癌(高级别),具有基底细胞标记阳性的特征,推测其可能是基底细胞型乳腺癌(basal-1ike breast carcinoma,BLBC)的前驱病变。展开更多
以钨酸(H_2WO_4)为原料,过氧钨酸(H_4WO_3 (O_2)_2)为前驱体,乙酸铵(CH_3COONH_4)为辅助剂,采用水热法在碳布上制备了一系列氧化钨(WO3)电极。利用X-射线衍射仪(XRD)及扫描电子显微镜(SEM)对水热合成的WO_3~a电极进行结构表征。在0.5 M ...以钨酸(H_2WO_4)为原料,过氧钨酸(H_4WO_3 (O_2)_2)为前驱体,乙酸铵(CH_3COONH_4)为辅助剂,采用水热法在碳布上制备了一系列氧化钨(WO3)电极。利用X-射线衍射仪(XRD)及扫描电子显微镜(SEM)对水热合成的WO_3~a电极进行结构表征。在0.5 M H_2SO_4溶液中,采用三电极体系,-0.7～0V(vs.SCE)的电位范围对一系列WO3电极进行循环伏安(CV)和恒电流充放电(CP)测试。考察了前驱液中CH_3COONH_4浓度、搅拌时间、双氧水(H2O2)的用量对WO3电极的微观形貌以及电化学性能的影响。其中1.33g H_2WO_4、0.1M CH3COONH4、6mL H_2O_2(30%)、搅拌10h得到前驱液,在180℃条件下水热反应12h,得到具有六方结构和单斜结构的纳米WO_3~a。在这一条件下合成的WO_3~a电极具有最优的电化学性能,比电容可达到4.53F/cm^2。展开更多
基金Funded by the Doctoral Fund of Southwest University of Science and Technology(Nos.19zx7131 and 18zx7132)the Applied Fundamental Research Projects of Science and Technology Department of Sichuan Province(No.2020YJ0333)+1 种基金the Science and Technology on Plasma Physics Laboratory:6142A04180405Science and Technology on Plasma Physics Laboratory:ZY2018-07。
文摘Porous Pt thin films were prepared on carbon papers by a single-step ultra-high dc magnetron sputtering method to obtain ideal electrodes for proton exchange membrane fuel cells.The platinum loading of the electrocatalyst layer is controlled at about 0.1 mg·cm^(-2).Structural characteristics and catalytic activities of the films were analyzed by scanning electron microscopy,atomic force microscopy,X-ray diffraction,cyclic voltammetry,and stress durability testing methods.The effect of treatment conditions of a substrate on the structural and performance characteristics of the catalytic films was shown as well.Films produced on acid-treated carbon papers at the argon pressure of 0.01 mbar possessed a homogeneous,highly developed surface along with a porous structure.Compared to Pt/TCPW(Toray carbon papers soaked in ultrapure water)electrodes,the film obtained on the acid-treated substrate had a larger electrochemical surface area(163.33 m^(2)·g^(-1))and exhibited better catalytic stability and durability due to a porous structure as a result of Pt particle accumulation.
文摘目的探讨乳腺基底细胞型导管内原位癌的组织病理学形态、免疫组化及其诊断和鉴别诊断。方法对7例乳腺基底细胞型导管内原位癌患者的临床组织病理学和免疫组化特征进行观察,并复习相关文献。结果7例乳腺基底细胞型导管内原位癌,肿瘤长径0.8~3.8cm,镜下瘤细胞为实体型、乳头状或筛状型,可见点状坏死及中央坏死(粉刺型),筛状型的筛孔多呈圆形,腔缘光滑,细胞无极性分化。7例中免疫组化检测CK5/6(+)7例,CK14(+)、CK17(+)和P63(+)各6例、EGFR(+)5例、CD117(+)4例,Ki-67阳性(+30%~60%)。结论乳腺基底细胞型导管内原位癌是一种特殊类型的导管内原位癌(高级别),具有基底细胞标记阳性的特征,推测其可能是基底细胞型乳腺癌(basal-1ike breast carcinoma,BLBC)的前驱病变。
