In this research,the ultrasonic ball milling technique has been used to fabricate lead zirconate titanate(PZT)ceramics.PZT with the composition nearly the morphotropic phase boundary(MPB):Pb(Zr_ 0.52Ti_ 0.48)O_3 was s...In this research,the ultrasonic ball milling technique has been used to fabricate lead zirconate titanate(PZT)ceramics.PZT with the composition nearly the morphotropic phase boundary(MPB):Pb(Zr_ 0.52Ti_ 0.48)O_3 was studied.The effect of milling time on phase formation of sample powder was examined by X-ray diffraction technique(XRD).Moreover,the physical,dielectric,piezoelectric properties and microstructure of PZT ceramics were investigated.The present results reveal that the ultrasonic ball milling technique results the homogeneous and small size of PZT powder.Furthermore,there is a significantly change occurs in the size of the particles with the short time of milling process.展开更多
To satisfy the measuring demands for the micro components of the industry, micro/nano probing systems with various ball tips have been developed. However, most of them cannot be used to measure the real micro geometri...To satisfy the measuring demands for the micro components of the industry, micro/nano probing systems with various ball tips have been developed. However, most of them cannot be used to measure the real micro geometrical features high precisely because the parameters of the ball tips are not appropriate. The ball tips with a diameter of less than 100 μm, a sphericity and eccentricity of far less than 1 μm are required urgently. A review on the state-of-the-art of ball tips of micro/nano probing systems is presented. The material characteristics and geometric parameters of now available ball tips are introduced sepa- rately. The existing fabrication methods for the ball tips are demonstrated and summarized. The ball tips＇ future trends, which are smaller diameter, better sphericity and smaller eccentricity, are proposed in view of the practical requirements of high-precision measurement for micro geometrical features. Some challenges have to be faced in future, such as the promotion and high-precision measurement for the small ball tip＇s sphericity and eccentricity. Fusion method without the gravity effect when the molten ball tip solidifying is a more suitable way to fabricate a small diameter ball tip together with a shaft.展开更多
目的：观察采用双支架技术模拟Viatorr支架在TIPS中的应用效果。方法整群抽取2004年6月至2012年6月本院收治肝硬化门静脉高压出血和顽固性腹水患者242例，将2004年6月至2009年6月采用裸支架技术治疗的入组患者186例设为裸支架组（对照...目的：观察采用双支架技术模拟Viatorr支架在TIPS中的应用效果。方法整群抽取2004年6月至2012年6月本院收治肝硬化门静脉高压出血和顽固性腹水患者242例，将2004年6月至2009年6月采用裸支架技术治疗的入组患者186例设为裸支架组（对照组），将2009年6月至2012年6月采用双支架技术模拟Viatorr支架方法治疗的入组患者56例设为模拟Viatorr组（观察组）。两组患者进行前后对照临床试验研究。两组患者在治疗前性别、年龄、肝功能Child分级及门静脉高压并发症等方面均无显著差异。模拟Viatorr组在分流道开通后先释放1枚8 mm ＆#215;60 mm的裸支架，根据球囊上肝静脉-门静脉切迹，释放1枚8 mm ＆#215;40 mm的覆膜支架，覆膜部分覆盖肝实质全程而不阻挡门静脉入肝血流，其余部分伸入肝静脉内。裸支架组（对照组）分流道开通后只放置1枚8 mm ＆#215;60 mm的裸支架。两组患者常规用弹簧栓子栓塞胃冠状静脉。结果模拟Viatorr组56例均获得成功，裸支架组186例中有2例不成功，改为其他治疗。技术成功率分别为100%和98.9%。两组分流道建立后门静脉压力分别下降了（18＆#177;5.7）cm H2O和（18＆#177;3.4）cm H2O。随访12～36个月，用彩色多普勒超声观察分流道通畅情况。模拟Viatorr组和裸支架组分流道累计通畅率分别为67.8%和41.9%，差异有显著统计学意义（P=0.0007）；模拟Viatorr组和裸支架组复发再出血率分别为21.4%和40%，差异显著有统计学意义（P=0.0056）；模拟Viatorr组和裸支架组肝性脑病发生率分别为19.6%和10.2%，差异无统计学意义（P=0.0605）。模拟Viatorr组和裸支架组在治疗顽固性腹水的有效率分别为80%和72.7%，差异无统计学意义（P=0.425）。模拟Viatorr组有1例患者术后出现腹腔感染，抗感染治疗后好转；1例患者于术后2个月出现支架肝静脉端“盖帽”，再次介入干预时未能成功。裸支架组有3例患者腹腔穿刺证实为腹腔内出血，经保守治疗后好转，无其他严重并发症发生。随访期间，模拟Viatorr组有7例（12.5%）、裸支架组有47例（25.2%）患者因分流道严重狭窄闭塞进行了1～3次再通术和支架植入术；模拟Viatorr组有5例、裸支架组有39例分别死于肝功能衰竭、肝癌和多器官衰竭。结论双支架模拟Viatorr支架方法能够提高TIPS中远期分流道通畅率，降低再出血率。展开更多
文摘In this research,the ultrasonic ball milling technique has been used to fabricate lead zirconate titanate(PZT)ceramics.PZT with the composition nearly the morphotropic phase boundary(MPB):Pb(Zr_ 0.52Ti_ 0.48)O_3 was studied.The effect of milling time on phase formation of sample powder was examined by X-ray diffraction technique(XRD).Moreover,the physical,dielectric,piezoelectric properties and microstructure of PZT ceramics were investigated.The present results reveal that the ultrasonic ball milling technique results the homogeneous and small size of PZT powder.Furthermore,there is a significantly change occurs in the size of the particles with the short time of milling process.
基金Supported by National Natural Science Foundation of China(Grant Nos.51675157,51475131)State Key Laboratory of Precision Measuring Technology and Instruments of China(Grant No.PIL1401)
文摘To satisfy the measuring demands for the micro components of the industry, micro/nano probing systems with various ball tips have been developed. However, most of them cannot be used to measure the real micro geometrical features high precisely because the parameters of the ball tips are not appropriate. The ball tips with a diameter of less than 100 μm, a sphericity and eccentricity of far less than 1 μm are required urgently. A review on the state-of-the-art of ball tips of micro/nano probing systems is presented. The material characteristics and geometric parameters of now available ball tips are introduced sepa- rately. The existing fabrication methods for the ball tips are demonstrated and summarized. The ball tips＇ future trends, which are smaller diameter, better sphericity and smaller eccentricity, are proposed in view of the practical requirements of high-precision measurement for micro geometrical features. Some challenges have to be faced in future, such as the promotion and high-precision measurement for the small ball tip＇s sphericity and eccentricity. Fusion method without the gravity effect when the molten ball tip solidifying is a more suitable way to fabricate a small diameter ball tip together with a shaft.
文摘目的：观察采用双支架技术模拟Viatorr支架在TIPS中的应用效果。方法整群抽取2004年6月至2012年6月本院收治肝硬化门静脉高压出血和顽固性腹水患者242例，将2004年6月至2009年6月采用裸支架技术治疗的入组患者186例设为裸支架组（对照组），将2009年6月至2012年6月采用双支架技术模拟Viatorr支架方法治疗的入组患者56例设为模拟Viatorr组（观察组）。两组患者进行前后对照临床试验研究。两组患者在治疗前性别、年龄、肝功能Child分级及门静脉高压并发症等方面均无显著差异。模拟Viatorr组在分流道开通后先释放1枚8 mm ＆#215;60 mm的裸支架，根据球囊上肝静脉-门静脉切迹，释放1枚8 mm ＆#215;40 mm的覆膜支架，覆膜部分覆盖肝实质全程而不阻挡门静脉入肝血流，其余部分伸入肝静脉内。裸支架组（对照组）分流道开通后只放置1枚8 mm ＆#215;60 mm的裸支架。两组患者常规用弹簧栓子栓塞胃冠状静脉。结果模拟Viatorr组56例均获得成功，裸支架组186例中有2例不成功，改为其他治疗。技术成功率分别为100%和98.9%。两组分流道建立后门静脉压力分别下降了（18＆#177;5.7）cm H2O和（18＆#177;3.4）cm H2O。随访12～36个月，用彩色多普勒超声观察分流道通畅情况。模拟Viatorr组和裸支架组分流道累计通畅率分别为67.8%和41.9%，差异有显著统计学意义（P=0.0007）；模拟Viatorr组和裸支架组复发再出血率分别为21.4%和40%，差异显著有统计学意义（P=0.0056）；模拟Viatorr组和裸支架组肝性脑病发生率分别为19.6%和10.2%，差异无统计学意义（P=0.0605）。模拟Viatorr组和裸支架组在治疗顽固性腹水的有效率分别为80%和72.7%，差异无统计学意义（P=0.425）。模拟Viatorr组有1例患者术后出现腹腔感染，抗感染治疗后好转；1例患者于术后2个月出现支架肝静脉端“盖帽”，再次介入干预时未能成功。裸支架组有3例患者腹腔穿刺证实为腹腔内出血，经保守治疗后好转，无其他严重并发症发生。随访期间，模拟Viatorr组有7例（12.5%）、裸支架组有47例（25.2%）患者因分流道严重狭窄闭塞进行了1～3次再通术和支架植入术；模拟Viatorr组有5例、裸支架组有39例分别死于肝功能衰竭、肝癌和多器官衰竭。结论双支架模拟Viatorr支架方法能够提高TIPS中远期分流道通畅率，降低再出血率。
