顶空气相色谱法测定大蒜主要含硫化合物在烹饪后油脂中的含量

采用顶空毛细管气相色谱法/氢火焰离子化检测器,分析了大蒜中主要含硫化合物(如:二烯丙基硫醚、二烯丙基二硫醚、二烯丙基三硫醚)在烹饪后油脂中的含量变化。优化的色谱条件为以DM2WAX石英弹性毛细管色谱柱进行分离,平衡温度为403 K,搅拌速度为500 r/min,平衡时间为20 min。在所考察的浓度范围内,该方法呈现出良好的线性关系,相关系数大于0.999,检出限为0.001~0.025 mg/L,3种含硫化合物的平均回收率为97.1%~103.0%。     

基于金属纳米球等离增强的高效钙钛矿/硅电池设计

以钙钛矿为顶、晶硅为底的钙钛矿/硅叠层电池可以提高太阳光谱的利用率,突破单结电池中的肖克利极限(SQ极限),是实现更高光电转换效率的有效途径之一.如何降低光子在电池表面和界面的传输损失,最大化响应层的吸收效率是其中的关键.本文通过时域有限差分法和严格耦合波分析,系统研究了不同种类金属纳米球对钙钛矿/硅叠层电池的光谱响应和能量转换效率的增强机制.结果表明,由于表面电子云对光波的共振增强,金属纳米结构的引入显著提升了光子进入到电池响应层的透射率,电池总的吸收光谱和量子响应效率因而得到明显提升.对于最优的Al纳米球,观察到的加权平均透射率从73.16%提升到79.15%,电池能量转换效率从23.09%提高到24.97%,效率相对提高了8.14%.     

THE OPTIMAL REINSURANCE-INVESTMENT PROBLEM CONSIDERING THE JOINT INTERESTS OF AN INSURER AND A REINSURER UNDER HARA UTILITY

This paper focuses on an optimal reinsurance and investment problem for an insurance corporation which holds the shares of an insurer and a reinsurer.Assume that the insurer can purchase reinsurance from the reinsurer,and that both the insurer and the reinsurer are allowed to invest in a risk-free asset and a risky asset which are governed by the Heston model and are distinct from one another.We aim to find the optimal reinsuranceinvestment strategy by maximizing the expected Hyperbolic Absolute...