为了提出一种有效且简易的线性压缩机设计和优化方案,本文针对一款商用Cryo S 100小型斯特林制冷机,推导出其动磁式线性压缩机中气体阻尼力和气体弹簧力的表达式,并采用COMSOL软件将压缩机动力模型和电磁模型相耦合,建立了联合仿真模型...为了提出一种有效且简易的线性压缩机设计和优化方案,本文针对一款商用Cryo S 100小型斯特林制冷机,推导出其动磁式线性压缩机中气体阻尼力和气体弹簧力的表达式,并采用COMSOL软件将压缩机动力模型和电磁模型相耦合,建立了联合仿真模型,模拟了不同负载下压缩机的动力特性,模拟结果与SAGE相吻合。通过空载下对线性压缩机的瞬态位移特性的测试和稳态下对电机比推力特性的测试,验证了耦合模型的准确性。展开更多
平行缝焊作为气密性封装的一种重要封装形式,以其适用范围广、可靠性高等优势被广泛应用。在高温共烧陶瓷(High Temperature Co-fired Ceramics,HTCC)产品气密性封装应用时,有诸多因素可能会引起产品密封不合格,导致电路失效。从产品盖...平行缝焊作为气密性封装的一种重要封装形式,以其适用范围广、可靠性高等优势被广泛应用。在高温共烧陶瓷(High Temperature Co-fired Ceramics,HTCC)产品气密性封装应用时,有诸多因素可能会引起产品密封不合格,导致电路失效。从产品盖板和底座的清洁度、预焊过程控制、封装夹具制作及封装参数的设置4个方面研究了平行缝焊工艺对HTCC产品气密性封装效果的影响。研究结果显示,为减少平行缝焊时陶瓷管壳所受到的热冲击,在脉冲周期内脉冲宽度要短,焊封能量应尽可能小,同时平行缝焊工艺中非封装参数影响的焊道质量也会影响HTCC产品气密性封装的效果。展开更多
In situ evaluation of cell cultivation on degrading poly(ε-caprolactone) (PCL) films was studied.New culture surroundings were constructed for cell growth by using PCL films as substrates and adding Pseudomonas cepac...In situ evaluation of cell cultivation on degrading poly(ε-caprolactone) (PCL) films was studied.New culture surroundings were constructed for cell growth by using PCL films as substrates and adding Pseudomonas cepacia lipase to accelerate biodegradation of PCL films.MTT experiments for 10 h indicated the low cytotoxicity of lipase solution with concentration up to 0.2 mg/mL for MG-63 cells growth on PCL films.With the optimized lipase concentration and degradation time,we studied cell growth behavior on dynamically changed PCL films by adding lipase to the culture surroundings.MTT,fluorescence microscopy and scanning electron microscopy (SEM) were used to evaluate cell viability,proliferation and morphologies.It was found that cell viability and proliferation were not affected by the added lipase solution negatively.In contrast,cells cultured on degrading PCL films showed good growth behavior with clear fusiform shape and pseudopods.Importantly,the enzymatic degradation of PCL films with cells attachment showed distinctive morphology compared to the degradation in lipase solution without cells.The simultaneous cell growth and PCL film degradation were well discussed in this work,which may better understand the interaction between cell growth and polymer degradation.展开更多
文摘为了提出一种有效且简易的线性压缩机设计和优化方案,本文针对一款商用Cryo S 100小型斯特林制冷机,推导出其动磁式线性压缩机中气体阻尼力和气体弹簧力的表达式,并采用COMSOL软件将压缩机动力模型和电磁模型相耦合,建立了联合仿真模型,模拟了不同负载下压缩机的动力特性,模拟结果与SAGE相吻合。通过空载下对线性压缩机的瞬态位移特性的测试和稳态下对电机比推力特性的测试,验证了耦合模型的准确性。
文摘平行缝焊作为气密性封装的一种重要封装形式,以其适用范围广、可靠性高等优势被广泛应用。在高温共烧陶瓷(High Temperature Co-fired Ceramics,HTCC)产品气密性封装应用时,有诸多因素可能会引起产品密封不合格,导致电路失效。从产品盖板和底座的清洁度、预焊过程控制、封装夹具制作及封装参数的设置4个方面研究了平行缝焊工艺对HTCC产品气密性封装效果的影响。研究结果显示,为减少平行缝焊时陶瓷管壳所受到的热冲击,在脉冲周期内脉冲宽度要短,焊封能量应尽可能小,同时平行缝焊工艺中非封装参数影响的焊道质量也会影响HTCC产品气密性封装的效果。
基金supported by the National Natural Science Foundation of China (50573085 & 50521302) and Chinese Academy of Sciences
文摘In situ evaluation of cell cultivation on degrading poly(ε-caprolactone) (PCL) films was studied.New culture surroundings were constructed for cell growth by using PCL films as substrates and adding Pseudomonas cepacia lipase to accelerate biodegradation of PCL films.MTT experiments for 10 h indicated the low cytotoxicity of lipase solution with concentration up to 0.2 mg/mL for MG-63 cells growth on PCL films.With the optimized lipase concentration and degradation time,we studied cell growth behavior on dynamically changed PCL films by adding lipase to the culture surroundings.MTT,fluorescence microscopy and scanning electron microscopy (SEM) were used to evaluate cell viability,proliferation and morphologies.It was found that cell viability and proliferation were not affected by the added lipase solution negatively.In contrast,cells cultured on degrading PCL films showed good growth behavior with clear fusiform shape and pseudopods.Importantly,the enzymatic degradation of PCL films with cells attachment showed distinctive morphology compared to the degradation in lipase solution without cells.The simultaneous cell growth and PCL film degradation were well discussed in this work,which may better understand the interaction between cell growth and polymer degradation.
