利用光譜分析法靜態測定等溫汽-液相圖

本文推导了严格的热力学关系,使仅根据混合物的饱和蒸气中各组分的体积浓度就可以作出液体混合物的等温蒸气压图并计算活度系数。叙述了一种测定浓度的光学方法。实际应用於苯-氯苯体系证明由静态方法所得的数据相当於真正的热力学平衡,因为数据符合Gibbs-Duhem关系。参考文献见英文部分。     

Unpredictability of Iteration Destination in an Integrate-and-Fire Circuit

Based on our previous study that discovered a new mechanism of the riddled-like basin appearance in piecewise continuous and noninvertible links of two conservative mappings, and the mechanism being the mixing of different attraction basins on a fat-fractal set, which was addressed as the forbidden region net [Phys. Rev. E 72 （2005） 025201（R）], we show numerically that the riddled-like attraction basins and the new mechanism appear in an integrate-and-fire circuit that can be described by piecewise continuous and noninvertible links of two dissipative mappings. This leads to the fact that vast increase of the precision of the initial condition results in practically no improvement in predictability of the iteration destination. Predictability is usually characterized by examining how error probability in the prediction, f（ε）, scales with the precision ε under the initial condition. Typically, f（ε） - ε^α with 0 ≤ α ≤ 1 being the uncertainty exponent. For riddled-like basins, a should be zero, which is in good agreement with the numerical simulation results.     

内埋炸药下超高韧性水泥基复合材料的抗爆性能

为研究超高韧性水泥基复合材料(ultra-high toughness cementitious composites, UHTCC)在内埋炸药爆炸下的抗爆性能和损伤破坏规律,对不同炸药埋深下的UHTCC和高强混凝土(high-strength concrete, HSC)进行了内埋炸药抗爆实验。得到了两种材料靶体的破坏状态,并利用接触爆炸的实验结果计算出了两种材料的抗爆性能参数。结果表明,在相同条件下,UHTCC抗爆性能优于高强混凝土。为了进一步探究UHTCC的抗压强度、抗拉强度以及拉伸韧性对靶体在内埋炸药下抗爆性能的影响,首先,采用改进的K&C模型对炸药埋深为40 mm的超高韧性水泥基复合材料靶体进行数值模拟,模拟结果与实验结果基本吻合,并根据数值模拟的结果得到了爆炸冲击波沿靶体径向衰减速度大于轴向衰减速度这一规律,验证了数值模型的有效性;然后,通过调整改进K&C模型中与抗压强度、抗拉强度以及拉伸韧性相关的参数,数值预测了不同抗压强度、抗拉强度以及拉伸韧性下UHTCC靶体的破坏状态,发现增强UHTCC的韧性可以有效防止靶体发生整体性破坏,增大UHTCC的抗拉强度可以减小靶体迎爆面的开坑直径,增大UHTCC的抗压强度对减小开坑直径效果不明显。     

不同形状金属光栅增强PTB7∶PC70 BM有机太阳能电池光吸收效率的研究

金属光栅会激发表面等离子激元,促进光吸收,将金属光栅引入PTB7∶PC70BM有机太阳能电池中,通过优化金属光栅形状,可增强电池的光吸收效率。本文使用有限元方法,研究了在活性层的底部置入不同形状金属光栅,例如方形,椭圆形以及圆形,后器件的光吸收效率。研究结果发现,方形光栅可以使活性层的总吸收率从平板结构的29;提高到52.9;,提高的幅度最大,椭圆形光栅次之,提高到49;,圆形光栅提高的最小,提高到45;。