Simplified Perovskite Solar Cell with 4.1% Efficiency Employing Inorganic CsPbBr3 as Light Absorber

Perovskite solar cells with cost‐effectiveness, high power conversion efficiency, and improved stability are promising solutions to the energy crisis and environmental pollution. However, a wide‐bandgap inorganic–semiconductor electron‐transporting layer such as TiO₂ can harvest ultraviolet light to photodegrade perovskite halides, and the high cost of a state‐of‐the‐art hole‐transporting layer is an economic burden for commercialization. Here, the building of a simplified cesium lead bromide (CsPbBr₃) perovskite solar cell with fluorine‐doped tin oxide (FTO)/CsPbBr₃/carbon architecture by a multistep solution‐processed deposition technology is demonstrated, achieving an efficiency as high as 4.1% and improved stability upon interfacial modification by graphene quantum dots and CsPbBrI₂ quantum dots. This work provides new opportunities of building next‐generation solar cells with significantly simplified processes and reduced production costs.     

（RbCl）108离子簇均相成核的分子动力学研究

分子动力学模拟测得熔融（RbCl)108离子簇在300K至600K温度时凝固的成核速率大于10^35m^-3s^-1,用均相成核的经典理论加以分析,估算得氯化铷离子簇的固液界面自由能σalT^1.4,用Grunasy提出的扩散界面理论加以分析,估算得扩展界面厚度约为0．195nm,σalT^0.97,2个理论在实验温度范围内没有明显判别,且均能较好地分子动力学模型的结果,但预测的较高温度下的成核速率有比较显著区别,因此进一步地研究将有助于鉴别它们。     

微电子封装中焊锡接点的界面应力奇异性

采用界面力学理论计算了不同形状的含铅/无铅焊锡接点界面应力奇异性指数,建立了焊锡接点的有限元模型,计算了线弹性、弹塑性和Johnson-cook材料模型的界面应力分布.结果表明:随着焊锡接点接触角的增加,界面应力奇异性增强;Sn37Pb/Cu界面比Sn3.5Ag/Cu和Sn3.0Ag0.5Cu/Cu界面的应力奇异性明显;弹塑性变形和应变率效应降低界面应力.     

细骨料品种对外掺MgO砂浆膨胀性能的影响研究

 为了阐明骨料岩性对MgO混凝土膨胀特性的影响规律及作用机理,研究了20,38,60℃水养护温度下不同骨料砂浆的膨胀率,并结合能谱、元素聚类及相分布等微观测试手段深入分析了水泥基体区与细骨料界面过渡区的微结构及元素富集特性。研究结果表明：养护温度从20℃提高至60℃时,砂浆膨胀率增大,且天然砂与辉石闪长岩砂浆的膨胀率最高,其次为灰岩砂浆,玄武岩砂浆最小。38℃水养条件下,辉石闪长岩砂浆和玄武岩砂浆界面区的Ca,Mg元素富集程度高于灰岩与天然砂砂浆,天然砂较高的表面孔隙率和表面含水率有助于吸引更多的MgO迁移至界面区,快速水化形成晶粒尺寸较大、结构较疏松的“外部膨胀水化产物”水镁石;骨料颗粒通过影响界面过渡区的元素富集特性、水化物相类型和形态来影响MgO砂浆的膨胀特性,含有细粉的人工细骨料可以通过改变外掺MgO水泥水化程度和MgO含量来改变MgO砂浆的特性。     

形状记忆合金增强复合材料界面剪应力研究

为研究形状记忆合金长纤维增强复合材料界面剪应力的分布情况,基于单纤维双圆柱拔出模型,推导了脱粘区和粘结区界面剪应力表达式.基于复合材料内部温度分布均匀,马氏体体积分数只与纤维内部轴向应力和温度相关等假设,分别讨论了恒定外应力荷载条件下温度(303、323、343 K)、预应变水平(0％、2％、4％、6％)及固定脱粘长度对界面剪应力分布的影响.数值模拟结果表明,通过控制外界温度和预应变水平,可以改变模型最大界面剪应力的值,进而控制界面脱粘现象的发生.对进一步研究SMA长纤维增强复合材料界面力学行为提供了一定的理论参考.     

Predicting Interfacial Loads between the Prosthetic Socket and the Residual Limb for Below-Knee Amputees – A Case Study

Abstract:  In this study, an artificial neural network (ANN) was deployed as a tool to determine the internal loads between the residual limb and prosthetic socket for below-knee amputees. This was achieved by using simulated load data to validate the ANN and captured clinical load data to predict the internal loads at the residual limb–socket interface. Load/pressure was applied to 16 regions of the socket, using loading pads in conjunction with a load applicator, and surface strains were collected using 15 strain gauge rosettes. A super-position program was utilised to generate training and testing patterns from the original load/strain data collected. Using this data, a back-propagation ANN, developed at the University of the West of England, was trained. The input to the trained network was the surface strains and the output the internal loads/pressure. The system was validated and the mean square error (MSE) of the system was found to be 8.8% for 1000 training patterns and 8.9% for 50 testing patterns, which was deemed an acceptable error. Finally, the validated system was used to predict pressure-sensitive/-tolerant regions at the limb–socket interface with great success.     

马氏体相变的界面吸引子模型

从经典的马氏体相界面运动方程出发,利用相平面分析,证明具有界面摩擦的马氏体相界面是吸引子,与理想的马氏体相界面的孤立子特征不同.通过对非线性方程解的分析,得到发生应力诱发马氏体相变的相界面趋向为焦点型定常吸引子,而热诱发相变的马氏体相界面趋向为结点型定常吸引子,因此考虑界面摩擦后相界面的运动与理想相界面的运动具有不同的非线性特征.