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摘要： Purpose / Aim: To evaluate the effect of load removal time and load capacity on µTBS of dual-cure resin cement bonded to CAD/CAM composite. Materials & Methods: In total, 48 -composite blocs (14.5x7x4mm 3) were prepared (Grandio Blocks, VOCO GmbH;...

关键词： 三维间隔机织物   玄武岩纤维   聚酰亚胺纤维   高性能纤维   高温环境   传热   数值模拟  

摘要： 为突破实验条件的限制研究高温环境下三维间隔机织物的传热机制和传热过程,以玄武岩/聚酰亚胺三维间隔机织物为研究对象,对其三维间隔结构进行参数化建模,并确定控制方程以及边界条件。利用有限元分析方法对该织物进行高温环境下的传热过程数值模拟,通过实验对比验证模型有效性,探究了玄武岩/聚酰亚胺三维间隔机织物的间隔高度以及间隔跨距对其传热性能的影响。结果发现:相较于间隔跨距,间隔高度对三维间隔机织物传热性能的影响更大,传热平衡状态时织物背面域点探针温度相差11.4℃;且在三维间隔机织物内部,同一时刻下同一水平面上的间隔纱温度略低于空气域温度。

关键词： aortic aneurysm   thoracoabdominal aorta   aortic dissection   coronary artery disease   myocardial infarction   CAD   coronary artery disease   LHB   left heart bypass   LVEF   left ventricular ejection fraction   MI   myocardial infarction   OR   odds ratio   PSM   propensity score matching   TAAA   thoracoabdominal aortic aneurysm  

摘要： Many patients undergoing thoracoabdominal aortic aneurysm (TAAA) repair have had a previous myocardial infarction (MI). To address the paucity of data regarding outcomes in such patients, we aimed to compare outcomes after open TAAA repair in patients with and without previous MI.

关键词： 超疏水   无氟   涤纶非织造织物   二氧化钛   油水分离  

摘要： 采用硅烷偶联剂KH560作为桥梁,十八烷基三氯硅烷(OTS)作为长疏水链结构,对纳米二氧化钛(TiO_(2))粒子改性制得OTS-KH560/TiO_(2)溶胶,并整理到织物上制备超疏水非织造织物。利用红外光谱、扫描电镜和X射线能谱表征织物表面化学结构、形貌和元素组成,通过测试水接触角表征织物表面疏水性能,分析TiO_(2)/OTS用量比、焙烘温度、焙烘时间等因素对于整理织物水接触角的影响。此外,研究疏水整理织物的耐酸碱性能、防污性能、油水分离性能和力学性能。结果表明:当TiO_(2)/OTS用量比为0.3 g/0.984 g,焙烘温度和焙烘时间分别为170℃和80 s时,整理织物表面的接触角可高达166.5°,且整理后的织物具有良好的耐酸碱性能、防污性能、油水分离能力、吸油性能和力学性能。

关键词： PFAS   法规   纺织品  

摘要： 全氟和多氟烷基化合物(PFAS)因其优异的热稳定性和耐降解性,在纺织品行业中得到广泛应用,如防水处理、防火涂层等。然而,PFAS的持久性、远距离迁移性、生物累积性和生物毒性对人类健康和环境造成了长期不良影响,被称为“永久性化学物质”。近年来,全球多国及国际组织对PFAS的管控日益严格,纺织品行业需积极应对这一趋势。本文综述了欧盟、美国、中国的PFAS法规更新情况,以及Bluesign、AFIRM、ZDHC等组织的最新要求,并探讨了纺织品行业的合规测试与应对建议。

关键词： 农业拖拉机   尾灯   CAD   CAE   双色塑件   模具  

摘要： 以农业拖拉机尾灯为研究对象,分析了尾灯的内部结构和工艺性,并针对双色模具的特殊性,分析了模具成型方案和设计流程,基于AutoCAD和CAE软件完成了尾灯双色塑件模具的设计。开模试验表明:该产品符合设计需求,整个产品结构稳定,透明度好,设计的模具结构合理、工艺流程可靠,能够满足实际的生产应用,工程应用价值较高。

关键词： 1+X”证书   数控技术专业   机械CAD/CAM课程   课程改革  

摘要： 为适应“1+X”证书试点工作的全面推行,充分发挥技能大赛在育人过程中的重要作用,文章通过深化职业教育中的“教师、教材、教法”改革,将专业教学标准与职业技能等级标准深度融入课程标准,对教学内容和课程设置进行优化和重构。并以云南机电职业技术学院数控技术专业核心课程机械CAD/CAM课程为例,积极探索课证融通、赛证融通的发展道路。

关键词： Conjugate cam   Heald frame   Biaxial   Yarn tension   Shedding mechanism   Theoretical profile   Proportional model  

摘要： For overcoming space limitations and load-bearing defects of traditional conjugate cam shedding on looms, a novel cam shedding system with double-shaft was developed by incorporating mechanism analysis, theoretical calculations, modeling and simulation, and experimental verification. The lifting motion of the heald frame is controlled by the cosine acceleration law, with MATLAB compiling the reverse program of the cam theoretical profile. A functional digital prototype is created in ADAMS/View using planar rod groups, gear transmission, and conjugate cam mechanism. The simulation results of considering yarn tension exhibited highly consistent swing arm and heald frame motion curves with numerical calculations, and the dynamic performance of the shedding system is affected by yarn tension, which leads to an increase in motor torque and acceleration oscillation in the low-frequency domain. Furthermore, an experimental proportional model was produced using 3D printing technology and tested for motion performance at varying rotational speeds, verifying the design's theoretical accuracy and practical feasibility, indicating that this mechanism runs smoothly and reliably in lifting and returning the heald frame by cam; meanwhile, the yarn deformation and shed characteristics are apparent, meeting the requirements of the shedding weaving process of plain fabric. The work in this paper effectively solves the problem of contact wear between the cam and rotor, which is conducive to design innovation and performance improvement of the conjugate cam shedding on high-speed looms.

关键词： 植绒   纺织品   耐洗色牢度  

摘要： 植绒纺织品在洗涤过程中,植绒可能部分或全部脱落,导致纺织品颜色变色,表面组织结构遭到破坏,严重损害产品外观质量和其他服用性能。目前缺乏针对植绒纺织品洗涤过程植绒牢固性能的测试方法与评价体系,无法统一规范产品的性能指标。探索耐洗色牢度测试过程中植绒牢固性能的结果表示与评价。通过样品试验,分析植绒耐洗色牢度的变色和植绒脱落的原因,并对出现植绒脱落时,测试结果表示和符合性评价提供建议,以提升相关产品的质量。

摘要： Purpose / Aim: This study aimed to investigate the fatigue behaviour of direct and CAD/CAM indirect restorative materials cemented to a dentine analogue substrate. Materials & Methods: Two resin-based direct restorative materials (G-ænial Universa...