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注氢铁基二元合金中辐照位错环演化及退火温度影响研究
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作者 李然然 殷玉鹏 +5 位作者 渡边英雄 易晓鸥 韩文妥 刘平平 詹倩 万发荣 《物理学报》 SCIE EI CAS CSCD 北大核心 2022年第13期293-300,共8页
本文基于注氢纯铁和铁基二元合金(Fe-3%Cr、Fe-1.4%Ni和Fe-1.4%Mn,质量分数)开展常规透射电镜(200 kV)的原位表征观察,揭示了材料中辐照位错环的形态、尺寸演化行为及退火温度影响,并依据辐照损伤演化理论、退火过程中位错环平均尺寸变... 本文基于注氢纯铁和铁基二元合金(Fe-3%Cr、Fe-1.4%Ni和Fe-1.4%Mn,质量分数)开展常规透射电镜(200 kV)的原位表征观察,揭示了材料中辐照位错环的形态、尺寸演化行为及退火温度影响,并依据辐照损伤演化理论、退火过程中位错环平均尺寸变化推断得到空位型位错环形成温度的范围.注氢纯铁中空位型位错环的形成温度(T_(c))约为500℃;添加Ni可使T_(c)降低至~450℃,添加Cr可使T_(c)升高至600℃以上,而Mn的作用与Cr相似,亦可使T_(c)升高.注氘实验和热脱附谱分析进一步表明,纯铁和铁基二元合金中空位型位错环的形成温度受氢同位素与空位结合、释放过程影响.合金元素Ni对氢同位素与空位的结合、释放有促进作用,故导致T_(c)降低;而Cr和Mn均对氢同位素与空位的结合、释放产生抑制作用,故导致T_(c)升高.本文展示的有关合金元素对空位型位错环形成温度影响的研究将有助于更深刻理解铁基合金体系中损伤结构演化和辐照肿胀产生机理. 展开更多
关键词 铁基二元合金 注氢/氘 空位型位错环 透射电镜
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Aluminum potassium sulfate and tannic acid sclerotherapy for Goligher Grades Ⅱ and Ⅲ hemorrhoids: Results from a multicenter study 被引量:11
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作者 Hidenori Miyamoto Takenori Hada +2 位作者 Gentaro Ishiyama Yoshito Ono hideo watanabe 《World Journal of Hepatology》 CAS 2016年第20期844-849,共6页
AIM: To show that aluminum potassium sulfate and tannic acid(ALTA) sclerotherapy has a high success rate for Grade Ⅱ and Ⅲ hemorrhoids.METHODS: This study was based on the clinical data of 604 patients with hemorrho... AIM: To show that aluminum potassium sulfate and tannic acid(ALTA) sclerotherapy has a high success rate for Grade Ⅱ and Ⅲ hemorrhoids.METHODS: This study was based on the clinical data of 604 patients with hemorrhoids who underwent ALTA sclerotherapy between January 2009 and February 2015. The objective of this study was to assess the efficacy of this treatment for Grades Ⅱ and Ⅲ hemorrhoids. Preoperative and postoperative symptoms, complications and success rate were all assessed retrospectively. Follow-up consisted of a simple questionnaire, physical examination and an anoscopy. Patients were followed-up at one day, one week, two weeks, one month, one year, two years, three years, four years and five years after the ALTA sclerotherapy.RESULTS: One hundred and sixty-nine patients were diagnosed with Grade Ⅱ hemorrhoids and 435 patients were diagnosed with Grade Ⅲ hemorrhoids. The one year, three year and five year cumulative success rates of ALTA sclerotherapy for Grades Ⅱ and Ⅲ hemo-rrhoids were 95.9% and 93.1%; 89.3% and 83.7%; and 89.3% and 78.2%, respectively. No significant differences were observed in the cumulative success rates after ALTA sclerotherapy between Grades Ⅱ and Ⅲ hemorrhoids(P = 0.09). There were forty-seven post-operative complications(low grade fever; anal pain; urinary retention; rectal ulcer; and others). No serious or life-threatening complications occurred and all cases improved through conservative treatment. At univariate analysis there were no predictive factors of failure.CONCLUSION: ALTA sclerotherapy has had a high success rate for Grade Ⅱ and Ⅲ hemorrhoids during five years of post-operative treatment. However, additional studies are needed to evaluate the efficacy of this ALTA sclerotherapy in the management of hemorrhoidal disease. 展开更多
关键词 SCLEROTHERAPY Aluminum potassium sulfate and tannic acid Goligher grade Minimally invasive treatment HEMORRHOID
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透明聚氨酯保温材料的制备
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作者 Masayoshi Fuji Chika Takai +1 位作者 hideo watanabe Kyoichi Fujimoto 《保温材料与节能技术》 2016年第2期1-4,9,共5页
纤维材料和泡沫塑料由于其极低的热导率常被用作绝热材料。但这类材料往往是不透明的,这种特性限制了它们的使用。在本文中,我们把含有中空纳米二氧化硅颗粒(HSNPs)的纳米孔聚合物膜分散入聚氨酯(Pu)基体中,首次制备出了透明的... 纤维材料和泡沫塑料由于其极低的热导率常被用作绝热材料。但这类材料往往是不透明的,这种特性限制了它们的使用。在本文中,我们把含有中空纳米二氧化硅颗粒(HSNPs)的纳米孔聚合物膜分散入聚氨酯(Pu)基体中,首次制备出了透明的有机绝热材料。以聚乙氧基硅氧烷(TEOS)为原料,通过溶胶一凝胶法制备出了核一壳结构的纳米颗粒,然后将核刻蚀掉,制备出了外壳是二氧化硅的空心纳米颗粒,即HSNPs。使用HSNPs的好处是,由于其独特的纳米尺寸,当其在纳米孔结构的聚合物膜中使用时,会阻滞空气分子流通的路径,从而形成了一种类似于真空的隔热效果。这种情况下,热量将不能沿着薄膜材料向外扩散,而只能在二氧化硅骨架上流动。使用HSNPs的另一个好处是,在凝胶一溶胶反应过程中,可以通过控制反应条件的方式在二氧化硅壳上增加低密度的缺陷。这种缺陷将大大降低二氧化硅壳的热导率。分散在聚合物膜中的HSNPs是制备透明保温材料的关键。 展开更多
关键词 绝热 空心二氧化硅纳米颗粒 透明膜 无机模板
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