【摘 要】
：
The preferred orientation of pyrolytic carbon coating is an important performance parameter for the safe use of artificial mechanical heart valve.In this paper, the selected area electron diffraction (SAED) analysis of pyrolytic carbon coating samples of
【机 构】
：
School of Mechanical Engineering,Hangzhou Dianzi University,Hangzhou 310018,China
论文部分内容阅读
The preferred orientation of pyrolytic carbon coating is an important performance parameter for the safe use of artificial mechanical heart valve.In this paper, the selected area electron diffraction (SAED) analysis of pyrolytic carbon coating samples of artificial heart valve was carried out by transmission electron microscopy (TEM), and the experimental method of characterizing the preferred orientation of pyrolytic carbon by electron diffraction spectrum, namely bacon anisotropy factor (BAF), was described,and the orientation angle and BAF corresponding to the electron diffraction spectrum were measured.The results show that the BAF value can directly reflect the anisotropy of pyrolytic carbon in the selected area. The BAF value range is from 1 to infinity, and the higher the preferred orientation is, the greater the value is. The BAF value decreases exponentially with the increase of orientation angle. When the pyrolytic carbon tends to be isotropic, the orientation angle tends to 180 and the BAF value tends to 1.
其他文献
目的:研究当归拈痛汤对类风湿关节炎(RA)成纤维样滑膜细胞自噬与凋亡的影响,进一步探讨当归拈痛汤防治RA的相关机制.方法:收集临床RA患者的滑膜组织,分离出成纤维样滑膜细胞(FLS)并进行培养,将RA-FLS细胞分为4组,分别为空白血清组、当归拈痛汤含药血清低、中、高剂量组.通过划痕实验,transwell侵袭实验检测当归拈痛汤对RA-FLS细胞迁移、侵袭能力的影响;Hoechst 33342法检测RA-FLS细胞凋亡水平;单丹磺酰尸胺(MDC)染色检测细胞自噬水平;实时荧光定量聚合酶链式反应(Real-
目的:在“心与小肠相表里”理论指导下,探究七圣丸治疗阿尔茨海默病的作用及其对回肠菌群的影响.方法:采用双侧脑室注射β-淀粉样蛋白1-42(Aβ1-42)的方法建立阿尔茨海默病(AD)模型,将大鼠随机分为正常组、假手术组、模型组及七圣丸低、中、高剂量组(5.6,11.2,22.4 g·kg-1·d-1)和多奈哌齐组(多奈哌齐,0.46 mg·kg-1·d-1),连续给药28 d后,采用水迷宫实验观察大鼠的空间记忆能力,酶联免疫吸附测定法(ELISA)检测海马组织中的Aβ㈨和核转录因子-κB (NF-κB),
Radiation therapy is a standard treatment for head and neck tumors. However, patients often exhibit cognitive impairments following radiation therapy. Previous studies have revealed that hippocampal dysfunction, specifically abnormal hippocampal neurogene
随着社会环境的变化、人口老龄化使恶性肿瘤的发生率逐年增高,肿瘤患者临终的生存期不足3个月,身体机能受损严重,增加了患者的痛苦.患者家属不仅要承担高额的经济负担,同时还承受失去亲人的痛苦,从而出现严重的负面心理反应,使正常生活能力下降.安宁疗护又称临终关怀,主要是针对那些治愈性治疗无反应患者,开展对肿瘤终末期患者在临终前通过控制痛苦和不适应症状,提供身体、心理、精神方面照顾和人文关怀等服务的安宁疗护工作,使其有尊严的走完生命的最后阶段,减轻患者的痛苦,缓解家属的心理应激反应.基于对安宁疗护“尊重患者权利”这
目的:通过观察苓桂术甘汤(LG)对体外阿尔茨海默病(AD)病理状态下血脑屏障模型的影响,探讨其对AD血脑屏障损伤后修复的具体机制.方法:将50只雄性SPF级大鼠,随机分为5组,分别灌胃7 d,2次/d,LG高、中、低剂量组以4.8,2.4,1.2 g·kg-1,西药组以盐酸多奈哌齐0.5 mg·kg-1,正常组以等体积生理盐水灌胃,末次灌胃1h后经腹主动脉取含药血清;以细胞共培养法构建AD体外血脑屏障损伤模型,实验分为正常组,模型组,LG高、中、低剂量组和盐酸多奈哌齐组,模型组加入β淀粉样蛋白1-42(A
本文通过系统梳理当前澳门特别行政区药品及医疗器械监管体系,分析已取得的成就及所面临的挑战,展望未来在粤港澳大湾区药品及医疗器械监管产业深度融合、深入合作的时代背景下,澳门药品及医疗器械监管系统的发展方向,为未来更好地衔接内地监管体系,更好地融入大湾区监管环境提供政策建议.
目的:研究新疆和广州地区接受二甲双胍治疗的2型糖尿病患者维生素B12水平.方法:选取2018年12月-2019年6月在中山大学孙逸仙纪念医院内分泌科住院的糖尿病患者和2019年7月-2020年9月在新疆博尔塔拉蒙古自治州人民医院住院的糖尿病患者各150例.收集所有研究对象的基本信息和实验室检查结果.结果:新疆地区的维生素B12水平均显著低于广州地区,差异有统计学意义(P<0.05).结论:新疆地区应用二甲双胍作为控糖药物的2型糖尿病患者其维生素B12水平更低,应引起新疆地区医务工作者的关注,并注意监测该人
Aging is the primary risk factor for various chronic disorders,especially neurodegeneration diseases,including Alzheimer\'s disease (AD) and Parkinson\'s disease (PD).It has been estimated that about one in ten individuals aged＞65 are affected by AD,a
The biological basis of consciousness is one of the hardest questions in Science [1].To understand how consciousness arises from physical components,the brain has been studied systematically for decades.Damage to some structures of the brainstem leads to
背景 慢性心力衰竭(chronic heart failure,CHF)患者常合并认知功能障碍(cognitive impairment,CI),且CHF合并CI者预后不良发生率较高,及早识别影响CHF患者发生CI的因素具有重要意义.目前,虽然有研究者对CHF患者发生CI的影响因素进行了探讨,但不同研究的结果之间存在较大差异.目的 系统评价CHF患者发生CI的影响因素.方法 于2021年8月,计算机检索PubMed、EmBase、The Cochrane Library、Web of Science、CI