Holographic Zone Plate and Its Combination Used for Conversion of Solar Energy

An on-axis holographic zone plate or an off-axis holographic zone plate used for the silicon solar cell will have a solar energy conversion factor of 2.5.And the combination of the two plates will have its conversion facftor of 5.Especially for the use of silver halide photographic emulsion,the cost can be cut down dramatically.     

瞬态电磁场与生物体相互作用的研究

本文研究了电磁脉冲与细胞体的相互作用机理,并给出了初步结论.     

Automatic features extraction of faults in PEM fuel cells by a siamese artificial neural network

In this paper, a procedure aimed at the automatic extraction of the features from polymer electrolyte membrane fuel cell impedance spectra is proposed. An artificial neural network that is trained by exploiting the similarity learning concept has been used. The network learns the features of the impedance spectra and maps each of them into the embedding space by clustering them accurately and by emphasising differences among spectra corresponding to different faults. The siamese network structure is optimised and the quality of the learnt representation is evaluated by analysing the clusters obtained in the features space. The dataset of experimental spectra has been augmented in two different ways and the results are compared. The clustering quality of the proposed siamese network is compared with the one of other state of the art approaches.     

Vapor‐Based Initiator Coatings for Atom Transfer Radical Polymerization

A novel polymeric initiator coating for surface modification via atom transfer radical polymerization (ATRP) is reported. The synthetic approach involves the chemical vapor deposition of [2.2]paracyclophane‐4‐methyl 2‐bromoisobutyrate and can be applied to a heterogeneous group of substrates including stainless steel, glass, silicon, poly(dimethylsiloxane), poly(methyl methacrylate), poly(tetrafluoroethylene), and polystyrene. Surface analysis using X‐ray photoelectron spectroscopy and Fourier‐transformed infrared spectroscopy confirmed the chemical structure of the reactive initiator coatings to be consistent with poly[(p‐xylylene‐4‐methyl‐2‐bromoisobutyrate)‐co‐(p‐xylylene)]. Appropriate reactivity of the bromoisobutyrate side groups was confirmed by surface initiated atom transfer radical polymerization of a oligo(ethylene glycol) methyl ether methacrylate. After solventless deposition of the CVD‐based initiator coating, hydrogel films as thick as 300 nm could be conveniently prepared within a 24 h timeframe via ATRP. Moreover, the polymerization showed ATRP‐specific reaction kinetics and catalyst concentration dependencies. In addition, spatially controlled deposition of the initiator coatings using vapor‐assisted microstructuring in replica structures resulted in fabrication of spatially confined hydrogel microstructures. Both protein adsorption and cell adhesion was significantly inhibited on areas that were modified by surface‐initiated ATRP, when compared with unmodified PMMA substrates. The herein described initiator coatings provide a convenient access route to controlled radical polymerization on a wide range of different materials. While demonstrated only for a representative group of substrate materials including polymers, metals, and semiconductors, this method can be expected to be generically applicable – thereby eliminating the need for cumbersome modification protocols, which so far had to be established for each substrate material independently.     

Electrokinetic motion of particles and cells in microchannels

This paper provides an overview of the electrokinetic phenomena associated with particles and cells in microchannel systems. The most important phenomena covered include electrophoresis, dielectrophoresis, and induced-charge electrokinetics. The latest development of these electrokinetic techniques for particle or cell manipulations in microfluidic systems is reviewed, in terms of the basic theories, mathematical models, numerical and experimental methods, and the key results/findings from the published literatures in the most recent decades. Some of the limitations associated with the negative field effects are discussed and the perspectives for the future investigations are summarized.     

VA和IPS液晶盒固有对比度与温度的关系

我们测量了介于“理想”正交偏光片组之间的VA和JPS液晶盒在不同温度下的固有漏光。在温度低于向列相到液态的转变（清亮点）温度时,测量到的VA液晶盒固有漏光与温度变化无关,相反,JPS液晶盒无论是o光模式还是e光模式结构中固有漏光都随温度的增加而增加。我们推导出基于向列相液晶指向矢涨落引起光散射的理论公式,以解释我们的实验结果。     

一种基于无线传感器网络的三维定位模型

分布式无线传感器网络节点的定位是一个重要而基本的问题,在诸如搜救、目标跟踪、供应链管理、减灾以及智能环境等领域具有重要的应用价值.将节点分布在具体的应用环境中,利用节点构成自组网,不需要特定的通讯设施,就可以感知和传送周围信息.在建筑项目的管理中,材料管理在管理成本中占有很大的比例,通过在建筑材料上安装RFlD,可以比较容易地实时检测它们的位置,甚至可以检测材料的状况.这样在很大程度上提高了生产效率,降低了建筑企业的成本.基于上述原因,提出了一个三维环境下的节点定位模型,并特别地对定位误差进行了分析.该模型已经成功地在建筑项目管理中得到了应用.