A Lie-group adaptive differential quadrature method to identify an unknown force in an Euler–Bernoulli beam equation

We recover an unknown space–time-dependent force in an Euler–Bernoulli beam vibration equation by an effective combination of the Lie-group adaptive method (LGAM) and the differential quadrature method (DQM). The layer-stripping technique is used to simplify this identification problem. The DQM is a feasible tool to semi-discretize the Euler–Bernoulli beam equation into a system of ordinary differential equations (ODEs) in time. Then, we can develop a two-point Lie-group equation to recover the unknown force through a few iterations. The success of the present method hinges on a rationale that the local in time ODEs and the global in time algebraic Lie-group equation have to be self-adapted during the iteration processes. The feasibility, accuracy and efficiency of the present method are assessed by comparing the estimated results with some exact solutions.     

Oil-field wastewater purification by magnetic separation technique using a novel magnetic nanoparticle

In the present work, oil-field wastewater purification through superconducting magnetic separation technique using a novel magnetic nanoparticle was investigated. The magnetic nanoparticle, which has a multi-shell structure with ferroferric oxide as core, dense nonporous silica as inter layer and mesoporous silica as outer layer, was synthesized by co-precipitation method. To functionalize the magnetic nanoparticle, plasma polymerization technique was adopted and poly methyl acrylate (PMA) was formed on the surface of the nanoparticle. The multi-shell structure of the nanoparticle was confirmed by transmission electron microscope (TEM) and the characteristic is measurable by FTIR. It is found that most of the pollutants (85% by turbidity or 84% by COD value) in the oil-field wastewater are removed through the superconducting magnetic separation technique using this novel magnetic nanoparticle.     

A hardware software co-design method for control transfer optimization in binary translation system

针对控制转移开销是影响二进制翻译和优化系统性能的主要因素,进行了提高二进制翻译优化系统性能的研究,提出并实现了硬件设计开销较小的基于硬件内容可寻址存储器(CAM)机制的软硬件协同设计方法.通过实验充分分析了CAM大小、软件替换算法对CAM命中率的影响,并根据分析提出了一种新颖的、软硬件结合的降低CAM访问缺失率的方法.该方法相对于传统的软件和硬件优化方法,硬件实现及验证复杂度低且优化效果明显.实验结果表明该方法使得二进制翻译系统整体性能提高了13.44％.该方法已实际应用于龙芯x86二进制翻译系统中.     

与或功能树的无损简化方法

当前概念设计中较大规模功能树存在解空间庞大、冲突定位困难的问题,对此提出基于与或功能树的无损简化方法。证明了无损收缩简化、无损删除简化、无损提取简化的相关定理,并籍此给出与或功能树的无损简化算法。最后通过实例,证明该算法可在保持逻辑等价和创新能力不损失的前提下有效降低问题的复杂度,从而提高了概念设计的效率。     

接地的应用讨论

接地工程的广泛性和重要性已是大家的共识,根据近年来的施工经验,对接地进行简要的介绍和探讨。     

Initial bond formation in thermosonic gold ball bonding on aluminium metallization pads

The morphological features of lift-off footprints on the aluminium metallization pads were investigated to gain an understanding of the effects of bonding parameters on formation of initial bonds during thermosonic gold ball bonding. The obtained results showed that metallurgical bonding initiated at the peripheral areas of the contact area situated along the direction of ultrasonic vibration. Those areas extended inwards with an increase in ultrasonic power. Both the external bonded area and central non-bonded area increased with increasing bonding force. Based on the evolution of footprints, the bonding models were proposed, and the effects of the bonding parameters on the formation of initial bonds were discussed.     

High response organic ultraviolet photodetector based on bis (2-methyl-8-quinolinato)-4-phenylphenolate aluminum

We report highly efficient visible-blind ultraviolet photodetectors based on 1,3,5-tris(3-methylphenyl-phenylamino)-triphenyamine (m-MTDATA) as donor and bis(2-methyl-8-quinolinato)-4-phenylphenolate aluminum (BAlq) as acceptor. Strong photoluminescence quenching of m-MTDATA by BAlq is observed manifesting the efficient photoinduced charge transfer occurs between m-MTDATA and BAlq. The optimized device exhibits a photocurrent of 172 μA/cm² at ?14 V under an illumination of 365 nm UV light irradiation with an intensity of 0.691 mW/cm², corresponding to a responsivity of 248 mA/W. We attribute the high response to the efficient electron transfer from the donor to the acceptor, the feasible level alignment match and the high carrier mobility of photoresponsive materials.     

Vibrational spectra of functionalized fullerenes containing amide

The set of three new hydrogen bonding functionalized fullerenes containing amide (PCB-t-BA, PCB-n-BA, and MPCB-t-BA) was investigated using the infrared absorption and Raman scattering spectroscopies. Additionally, the quantum chemical calculations of the equilibrium geometry and normal mode vibrations of the molecules were performed. Role of hydrogen bonds (HB) in the investigated samples was under our particular attention. Bifurcated HB was suggested.     

Composition and annealing effects in solution-processable functionalized graphene oxide/P3HT based solar cells

Characterization of a solution-processable functionalized graphene oxide (SPFGraphene oxide) was investigated by FT-IR spectroscopy and the result of elemental analysis showed that the isocyanate treatment results in the functionalization groups in SPFGraphene oxide. Doping SPFGraphene oxide to P3HT based solar cells induces absorbing spectra more strongly and a great quenching of the photoluminescence of the P3HT. With an increase in the SPFGraphene oxide content, the overall performances of the hybrid devices increases first, reaching the peak efficiency for the 10 wt% SPFGraphene oxide content, and then decreases. After annealing at 160 °C for different time durations, the device containing 10 wt% of SPFGraphene oxide for 10 min shows the best performance with a power conversion efficiency of 1.046%, an open-circuit voltage of 0.73 V, a short-circuit current density of 3.98 mA cm^?2 and a fill factor of 0.36 under simulated AM1.5G conditions at 100 mW cm^?2; The similar content one for 20 min shows η value of 1.013%, which is lower than the former one to a small extent for longer annealing duration. The graphene has the potential to act as the next-generation material in the photovoltaic devices and other applications for ease of preparation, low price, large surface area, high conductivity and excellent transparency.     

弹簧支吊架的选用及设计

详细描述和说明管道设计中弹簧支吊架的选用及设计,重点阐述弹簧支吊架的分类、结构、类型和选型等。指出设计和施工中应注意的问题。