Concept and demonstration of an intermediate band tandem device for solar energy conversion

We have realized a tandem solar cell design that combines a pin‐junction with a photovoltaic intersubband absorber. This concept allows harvesting light in the visible range and the near‐ and mid‐infrared at the same time, and theoretically, energy conversion efficiencies beyond the Shockley–Queisser‐limit could be achieved. A test structure was grown, and the operation of this concept could be confirmed, in principal with an optical two‐beam experiment. The basic characteristics of the device can be explained with an equivalent circuit design that consists of three individual cells, and we find an obvious analogy to the concept of the intermediate band solar cell with noteworthy advantages at some points. Our results show, that for a working device it is crucial to adjust the properties of the photovoltaic intersubband absorber for optimal charge separating performance at the working point of the solar cell. Copyright © 2015 John Wiley & Sons, Ltd.     

基于LCC和量子遗传算法的电动汽车充电站优化规划

电动汽车充电站优化规划是电动汽车与智能电网灵活互动的重要研究内容之一。面向电动汽车充电站运营周期,详细分析了充电站的成本效益及全寿命周期成本（LCC）的计算方法;基于上述工作,提出利用交通路网车流量信息估算充电站容量,以充电站运营商获得的净现值收益最大为优选目标,以交通路网车流量、电网电能质量和经济性、用户充电需求为约束条件,确定充电站的选址和容量;进一步地,提出了计及LCC的充电站优化规划模型,并采用量子遗传算法求解该模型。算例仿真表明,优化规划模型及其求解方法有效。     

复合热稳定剂对绝缘纸协同抗老化效应的分子模拟研究

为了从微观层面探究热稳定剂的复合添加对绝缘纸协同抗热老化特性的影响机理,以双氰胺、三聚氰胺为热稳定剂研究对象,对老化过程中的热稳定剂、β-D-吡喃葡萄糖分子、水分子和小分子酸等进行了量子化学计算,利用前线轨道理论考察了不同分子之间的化学反应活性。此外,采用分子动力学模拟软件,搭建了末添加、单一添加和复合添加热稳定剂的四种纤维素含水含酸模型,从纤维素与水分子、蚁酸分子的氢键结合数、相互作用能这两个方面考察了不同改性体系的差异及抗老化性能差异的机理。结果表明:热稳定剂分子与水分子、小分子酸的化学反应活性要强于β-D-吡喃葡萄糖分子与这些物质的反应活性;两种热稳定剂分子分别与水分子、小分子酸的反应活性存在差异,复合添加可以集中二者的优势,起到协同延缓绝缘纸老化的效果;双氰胺与三聚氰胺的复合添加在降低纤维素分子对水分子、蚁酸分子的吸附能力上存在协同作用。     

量子点敏化太阳电池对电极材料研究进展

作为第三代太阳电池,量子点敏化太阳电池因兼具低成本和高理论转化效率而备受关注.对电极是量子点敏化太阳电池的重要组成部分,是影响电池的光电转换性能及稳定性的重要因素之一.介绍了量子点敏化太阳电池对电极的功能和制备方法,重点介绍了对电极材料的分类及研究进展,并就对电极材料的发展前景进行了展望.     

基于量子粒子群算法多目标优化的配电网动态重构

为保证配电网动态重构后系统安全稳定的运行,提出了以网损和节点电压稳定性为目标函数的量子粒子群算法的配电网动态重构。针对配电网动态重构过程中时段划分问题,提出以负荷曲线的单调性和幅值变化大小为依据初步划分时间段落。采用整数型量子粒子群算法进行动态重构,重构过程中以相邻时段的网损变化值的关系获取最佳重构段落,然后综合考虑配电网网损最小和节点电压值最大且波动最小为目标寻找最佳重构结构。以IEEE33配电系统为例验证了所提方法的有效性和实用性。     

Designing of anion‐functionalized ionic liquids for efficient capture of SO2 from flue gas

Five kinds of anion‐functionalized ionic liquids (ILs) with different basicity and substituent were selected, prepared and applied in the capture of SO₂ from flue gas, where the concentration of SO₂ is only 2000 ppm. The effect of the anion on SO₂ absorption capacity, desorption residue, and available absorption capacity under 2000 ppm was investigated. The relationship between available absorption capacity and absorption enthalpy was also studied. Through a combination of thermodynamic analysis and quantum calculation, the results indicated that the effect of the cation in the IL on absorption enthalpy was significant. However, the effect of chain length in the cation was weak. Hence, a new IL with low molecular weight, [P₄₄₄₂][Tetz], was further designed and applied for the capture of SO₂, which shows the high absorption capacity of 0.18 g SO₂ per g IL and excellent reversibility for 2000 ppm SO₂. © 2015 American Institute of Chemical Engineers AIChE J, 61: 2028–2034, 2015     

石墨烯量子点的制备与表征

介绍了一种改进的溶剂热法制备石墨烯量子点(GQDs)。该方法以N,N-二甲基甲酰胺(DMF)和氧化石墨烯(GO)作为溶剂和原料,过程中会对GO进行微波膨胀预处理,然后进行反应。分别采用紫外可见吸收、光致发光、红外、透射电镜对石墨烯量子点进行结构、形貌以及荧光性能的表征。通过该方法制备的GQDs的荧光发射光谱表明其具有可激发性且具有良好的荧光性能。     

CdTe/CdS量子点荧光猝灭法测定盐酸西替利嗪

建立一种基于纳米材料的荧光性质测定盐酸西替利嗪含量的新方法,盐酸西替利嗪能使硫化镉包被的碲化镉核壳型量子点(CdTe/CdS QDs)发生规律性的荧光猝灭,研究二者相互作用的最佳条件,从而建立测定盐酸西替利嗪含量的方法。结果表明:盐酸西替利嗪的浓度在0.40~42μg/m L范围内有良好的线性关系(r=0.9992),检测限为2.50×10-2μg/m L,回收率为93.80%~97.00%。结论:此方法简便、快捷、可靠,适用于盐酸西替利嗪的含量测定。     

CN+HCNO反应机理理论计算

我们计算了CN+HCNO反应的反应势能面,使用的方法为QCISD(T)/6-311g(d,p)//UB3LYP/6-31g(d,p)。在计算中我们发现了31个异构体,40个过渡态。为了进一步考虑电子相关我们在QCISD(T)/6-311g(d,p)水平上做了单点能量计算。在改革中可能的初始连接方式中,我们发现进攻碳原子形成异构体b1和b2是最可行的连接方式,主要是因为这是一个无势垒的过程。通过热力学和动力学分析,我们确定通道P4(NCO+HCN)和P2(N2O+HCCO)应该是最可几产物。     

Microwave-Assisted Synthesis of Glutathione-Capped CdTe/CdSe Near-Infrared Quantum Dots for Cell Imaging

These glutathione (GSH)-conjugated CdTe/CdSe core/shell quantum dot (QD) nanoparticles in aqueous solution were synthesized using a microwave-assisted approach. The prepared type II core/shell QD nanoparticles were characterized by UV–Vis absorption, photoluminescence (PL) spectroscopy, X-ray powder diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). Results revealed that the QD nanoparticles exhibited good dispersity, a uniform size distribution and tunable fluorescence emission in the near-infrared (NIR) region. In addition, these nanoparticles exhibited good biocompatibility and photoluminescence in cell imaging. In particular, this type of core/shell NIR QDs may have potential applications in molecular imaging.