随着工程电介质领域研究的发展,诸多没有得到公认解释的问题逐渐出现,为此,本文提出了几个重要的问题及思考以供相关研究工作者参考。1994年Lewis首次提出了纳米电介质,2003年至今已成为工程电介质领域的研究热点,但从20余年该领域的研...随着工程电介质领域研究的发展,诸多没有得到公认解释的问题逐渐出现,为此,本文提出了几个重要的问题及思考以供相关研究工作者参考。1994年Lewis首次提出了纳米电介质,2003年至今已成为工程电介质领域的研究热点,但从20余年该领域的研究内容、作者的原意以及新近又提出的纳米结构电介质来看,我们认为应把名称改为纳米电介质复合物,并按照低维物理对纳米电介质作了重新定义。分析了Lewis与Tanaka界面的具体含义,提出了纳米高聚物复合物硬/软界面及其具有结构复杂性、不确定性与易变性的新概念,并剖析了硬、软表面的尺度及理化特性。提出了从A Einstein还原论、P W Anderson的层展现象与R P Feynmann的思维方法以启迪相关研究的新思维。从空间电荷限制电流(SCLC)存在条件的约束和高聚物或其复合物中由于自身结构的多层次性、复杂界面、电极接触以及共存的电子与离子电导等因素的严重影响,提出了从欧姆区过渡到高场区(即电极注入的SCLC区)不完全是由一种与注入载流子相同的载流子决定的想法,特别是要严格审视在测量条件确定时,离子电导对低场与高场区电流的贡献。为此,列出了离子电导与电子电导的主要特征与区别方法。针对脉冲有关的测量空间电荷的方法,特别是已成为国际上测量空间电荷主流方法的脉冲电声(PEA)方法,提出了PEA的优点与不足之处,以及如何去校准测量结果的正确性、重复性,如依据高聚物结构的特征,建立压激电流(pressure stimulated current,PSC)装置,正确判断电子、离子、偶极子梯度产生的空间电荷,以弥补PEA测量的严重不足。展开更多
应用经硅烷偶联处理后的纳米氧化镁(MgO)粉末与低密度聚乙烯(low density polyethylene,LDPE)共混,制得MgO/LDPE复合介质。高成分衬度扫描电镜(scanningelectron microscope,SEM)中图像表明,粒径为100 nm左右的MgO纳米粒子均匀的分散于...应用经硅烷偶联处理后的纳米氧化镁(MgO)粉末与低密度聚乙烯(low density polyethylene,LDPE)共混,制得MgO/LDPE复合介质。高成分衬度扫描电镜(scanningelectron microscope,SEM)中图像表明,粒径为100 nm左右的MgO纳米粒子均匀的分散于介质中。通过电声脉冲法(pulsed electro-acoustic,PEA)测试发现,当纳米MgO填料的质量分数为4%时,可以有效抑制空间电荷的注入,伏安特性的实验结果表明,复合介质拥有更高的空间电荷注入阈值场强。通过电树枝实验,发现复合介质可以抑制电树枝的引发和生长。最后,对实验结果进行了分析,探讨了纳米复合介质抑制空间电荷和树枝化生长的机制。纳米颗粒与基体材料界面电荷行为可能是复合介质电学性能改善的原因。展开更多
A total of 85 interspecific hybrid F2 (Cyprinus carpio var.wuyuanensis ×Cyprinus pellegrini pellegrini) were cooled to specific temperatures and held at those temperatures over a maximum of 4 days in a water-re...A total of 85 interspecific hybrid F2 (Cyprinus carpio var.wuyuanensis ×Cyprinus pellegrini pellegrini) were cooled to specific temperatures and held at those temperatures over a maximum of 4 days in a water-recycled and temperature-controlled aquarium inside.As a result,the blood homeostasis of experimental fish changed violently as acute temperature changed from 16 ℃ to 10 ℃ and 4 ℃ at a rate of 1 ℃·h-1 according to the data we collected.Whole blood pH,also called extracellular pH(pHe) were very sensitive to temperature changes,where there was a significant difference between 10 ℃(7.41) and 16 ℃(7.17)(P<0.01),compared to other values of hematology and serum chemistry.When the water temperature was continually decreased to an extreme temperature of 4 ℃,the content of Na+ of serum decreased remarkably in comparison with that of 10 ℃ and 16 ℃,which was 85.2 mmol·L-1,113.3 mmol·L-1 and 118.7 mmol·L-1,respectively.The values of hematology and serum chemistry also altered in gentle temperature changes of(10±2) ℃ and(4±2) ℃.Most values of serum chemistry and pH changed significantly,whereas the values of blood plasma changed slightly.pH was up slowly in 4 days at(10±2) ℃ and down slowly in 3 days at(4±2) ℃.A variety of values of serum chemistry changed remarkably both at(10±2) ℃ and(10±2) ℃,but the values of TP,TG and ALB only changed significantly at(4±2) ℃.These results distinguished at least two mechanisms involved in cold-induced stress in hybrid F2.Cold-induced pH changes resulted in other values altered.What’s more,pH correlated negatively with water temperature above 10 ℃,and the content of Na+.We also found that gentle temperature changes will be physiologically compensated for on day one at(10±2) ℃ and on day 2 at(4±2) ℃ in hybrid F2.展开更多
文摘随着工程电介质领域研究的发展,诸多没有得到公认解释的问题逐渐出现,为此,本文提出了几个重要的问题及思考以供相关研究工作者参考。1994年Lewis首次提出了纳米电介质,2003年至今已成为工程电介质领域的研究热点,但从20余年该领域的研究内容、作者的原意以及新近又提出的纳米结构电介质来看,我们认为应把名称改为纳米电介质复合物,并按照低维物理对纳米电介质作了重新定义。分析了Lewis与Tanaka界面的具体含义,提出了纳米高聚物复合物硬/软界面及其具有结构复杂性、不确定性与易变性的新概念,并剖析了硬、软表面的尺度及理化特性。提出了从A Einstein还原论、P W Anderson的层展现象与R P Feynmann的思维方法以启迪相关研究的新思维。从空间电荷限制电流(SCLC)存在条件的约束和高聚物或其复合物中由于自身结构的多层次性、复杂界面、电极接触以及共存的电子与离子电导等因素的严重影响,提出了从欧姆区过渡到高场区(即电极注入的SCLC区)不完全是由一种与注入载流子相同的载流子决定的想法,特别是要严格审视在测量条件确定时,离子电导对低场与高场区电流的贡献。为此,列出了离子电导与电子电导的主要特征与区别方法。针对脉冲有关的测量空间电荷的方法,特别是已成为国际上测量空间电荷主流方法的脉冲电声(PEA)方法,提出了PEA的优点与不足之处,以及如何去校准测量结果的正确性、重复性,如依据高聚物结构的特征,建立压激电流(pressure stimulated current,PSC)装置,正确判断电子、离子、偶极子梯度产生的空间电荷,以弥补PEA测量的严重不足。
文摘A total of 85 interspecific hybrid F2 (Cyprinus carpio var.wuyuanensis ×Cyprinus pellegrini pellegrini) were cooled to specific temperatures and held at those temperatures over a maximum of 4 days in a water-recycled and temperature-controlled aquarium inside.As a result,the blood homeostasis of experimental fish changed violently as acute temperature changed from 16 ℃ to 10 ℃ and 4 ℃ at a rate of 1 ℃·h-1 according to the data we collected.Whole blood pH,also called extracellular pH(pHe) were very sensitive to temperature changes,where there was a significant difference between 10 ℃(7.41) and 16 ℃(7.17)(P<0.01),compared to other values of hematology and serum chemistry.When the water temperature was continually decreased to an extreme temperature of 4 ℃,the content of Na+ of serum decreased remarkably in comparison with that of 10 ℃ and 16 ℃,which was 85.2 mmol·L-1,113.3 mmol·L-1 and 118.7 mmol·L-1,respectively.The values of hematology and serum chemistry also altered in gentle temperature changes of(10±2) ℃ and(4±2) ℃.Most values of serum chemistry and pH changed significantly,whereas the values of blood plasma changed slightly.pH was up slowly in 4 days at(10±2) ℃ and down slowly in 3 days at(4±2) ℃.A variety of values of serum chemistry changed remarkably both at(10±2) ℃ and(10±2) ℃,but the values of TP,TG and ALB only changed significantly at(4±2) ℃.These results distinguished at least two mechanisms involved in cold-induced stress in hybrid F2.Cold-induced pH changes resulted in other values altered.What’s more,pH correlated negatively with water temperature above 10 ℃,and the content of Na+.We also found that gentle temperature changes will be physiologically compensated for on day one at(10±2) ℃ and on day 2 at(4±2) ℃ in hybrid F2.