The band structure and equi-frequency contours for the holographical photonic crystals (PhCs) were calculated by using plane wave extension method, and the conditions for negative refraction in PhCs were analyzed as well as the frequency band. The finite-difference time-domain method was used to verify the conclusion, and it is shown that negative refraction can be clearly observed in the holographical PhCs within a wide frequency band and a large incident angle scope. The research on the negative refraction in holographical PhCs will provide a new idea for the design and fabrication of the left-handed negative-index materials.

Dispensing pattern is important for flip-chips underfill filling quality. This paper uses three-dimensional flow model to simulate underfill capillary flow and filling process for L and I dispensing patterns. The model reckons in influences of surface tension, contact angle and radius of curvature, especially contact angle and radius of curvature at wall of gap between chip and substrate, side wall of chip and surface of sold bump joints. In order to track the moving interface, the VOF model is applied. On the other hand, an experimental device has been constructed to research underfill filling process of the two dispensing patterns. Both simulation results and experiment results show that dispensing patterns have great influences on underfill filling velocity and flow front profile. In L filling pattern, underfill flow velocity is faster in diagonal direction. Comparing with experimental results and simulation results, it can be concluded the 3-D simulation model established can simulate underfill filling process well for the both L type and I type dispensing pattern.

The fluid flow in the fluid jetting dispenser was analyzed. We present a Numerical study of the jetting process using ANSYS fluid-structure interaction (FSI) analysis tools. The effects of gap between ball-needle and wall, the diameter of fluid chamber, the shape of the needle, the separation angle of dispensing body and the diameter of nozzle etc to mass flow rate are described. The calculation formula of cumulative fluid volume and mean flow velocity are deduced. The distribution of stress of adhesive in the jetting dispenser is obtained. Combining it with data by MATLAB show that the solution is effective, which provides a theoretical basis for choosing appropriate structural parameters of liquid jet-dispenser.

In this paper, the transmission characteristic in nano-size metallic photonic crystals (MPCs) is studied with the finite difference time domain (FDTD) method. It's show that the size and the layout of the metal decide the transfer characteristic of the metallic photonic crystals.

Using plane wave expansion (PWE) method and finite-difference time-domain (FDTD) method, we study the photonic band gap (PBG) and transmission properties of two-dimensional photonic crystals (PCs). A holographic fabrication design is used to construct the two-dimensional PCs in our work. To produce the lattice holographically, we use an equation to demonstrate a light intensity distribution. In this equation, there are several variant to control the lattice constant, the shape of dielectric columns, etc. The PBG calculation results using PWE method and FDTD method agree with each other very well.

时域多分辨分析(MRTD)算法和高阶时域有限差分法(HO-FDTD)是目前解决电大尺寸电磁结构仿真的有效手段.导出了基于Daubechies小波尺度函数的MRTD算法和HO-FDTD算法的通用差分公式和数值色散方程,并详细讨论了空间步长、时间步长以及电磁波传播方向对二者数值色散误差的影响.结果证明,MRTD算法与HO-FDTD算法非常相似,但HO-FDTD算法的数值色散特性优于具有相同展开项个数的MRTD算法.

A facile method for the synthesis of highly functionalized 1-oxadecalone derivatives is described via the Diels–Alder reaction of 2,3-dihydro-4-pyrone dienophiles with electron rich dienes. By this process a variety of functional groups and substitution patterns can be incorporated into the oxadecalone framework.

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Removal of the benzotriazolyl moiety of alpha-benzotriazolyl ketones by samarium diiodide at room temperature to give the corresponding ketones in good yields is described.

Tosylhydrazones can be rapidly converted into corresponding carbonyl compounds in good to excellent yields with thallium trinitrate (TTN) under mild conditions.

Sulfonyl halides can be readily reduced to corresponding disulfides with SmI2/THF/HMPA system in moderate to good yields at 60 degrees C.

β-Ketosulfones are readily reduced by TiCl 4 –Zn to give corresponding ketones in good yields under mild conditions.

beta-Ketosulfones can be readily desulfonylated with TiCl4/Sm system to give corresponding ketones in acceptable yields in THF under mild conditons.

1-(Benzotriazol-1-yl) unsymmetrical diorganyl selenides and tellurides were synthesized via replacement of chlorine atom in 1-(benzotriazo-1-yl) -1-chloromethane with selenoIate and tellurolate anions promoted by SmI2.

Homoallyl amines can be readily prepared in good to excellent yields via reaction of N-aminoalkylbenzotriazoles with allylsamarium bromide in THF at room temperature.

TiCl4/Sm system reduces arylsulfonyl chlorides and sodium arylsulfinates to corresponding diaryldisulfides in moderate to good yields in THF at 60 degrees C.

Imines can be readily allylated with samarium/allyl bromide system to afford homoallylamines in satisfactory yields in THF under mild conditions.

TiCl4/Sm system reduces sulfoxides rapidly to the corresponding sulfides in good yields in THF at room temperature.