Preparation and application of photosensitive copolymers for PDP barrier ribs formed by photolithography

In this work, the photosensitive paste was prepared. It was comprised of inorganic particles and a photosensitive organic component. The inorganic particles included glass, ceramics, and metals. The organic component should contain at least the following photosensitive materials: photosensitive monomers, photoreactive copolymer and photopolymerization initiators. The photoreactive copolymer played a role of an adhesive in the photosensitive paste. Meanwhile in the development stage, the carboxyl groups of the copolymer reacted with the alkalescent developer. Following this, the unexposed part must be removed and an excellent pattern can be formed. A series of three-component acrylic copolymers (MAA/St/MMA) were designed, and then synthesized via free radical polymerization. Subsequently glycidyl methacrylate (GMA) was employed to modify the prepared copolymers through ring-opening reactions between the carboxyl groups and the epoxide groups. Eventually the photosensitive copolymers were obtained and used to form the barrier ribs of PDPs. The chemical structure, glass transition temperature, acid value and molecular weight of photosensitive copolymers had different effects on the structure and pattern of PDP barrier ribs. Through analyzing effects of different polymer performance parameters on the patterns of barrier ribs, the optimal photosensitive copolymer was acquired.     

离散倾斜肋的传热强化及流动特性

本文以高湿透平叶片中腔内部冷却为应用背景，对两相对壁面具有三维离散斜肋的方形收敛通道内的传热进行了实验研究。本文获得的详尽的局部换热系数图谱、平均换热系数及复杂的近壁流场，可用于强化传热的设计。     

正六边形板式换热器传热和流动特性研究

本文研究了一种具有球面肋的正六边形板式换热器,分别对其两流体和三流体换热的情况进行数值模拟,讨论了其在顺流和逆流状态下的性能.与60°的人字形板式换热器进行比较,正六边形板式换热器在单位压降下的综合传热性能较优.本文还拟合了传热准则方程式和摩擦系数方程式.结果表明,该种新型板式换热器结构紧凑,布置灵活,具有好的综合传热...     

多种冲击载荷条件下的人体肋骨骨折有限元分析

旨在研究不同碰撞载荷条件下基于不同失效模型的人体肋骨骨折机理. 为此采用已验证的人体有限元胸部模型来分析人体肋骨骨折现象. 该模型基于人体解剖学结构,包含了人体胸椎、腰椎、肋骨、胸骨、肋间软骨、胸腹部器官和其他的软组织,定义的生物材料参数都基于已有的文献记载. 基于人体在损伤生物力学领域内一些较为典型的肋骨骨折失效模型,根据已发表文献中的人体标本实验载荷条件模拟了人体肋骨结构在不同冲击载荷下的骨折现象,并与这些实验结果进行了对比分析. 所引用的实验结果包括单根肋骨强度结构实验和人体胸部正面碰撞块冲击实验. 从文中有限元仿真分析的结果来看,针对不同的载荷条件,不同肋骨骨折失效模型的适用性各不相同. 该人体胸部有限元模型可用于车辆交通事故中冲击载荷条件下的人体肋骨损伤生物力学研究.      

Experimental investigation on submicron rib waveguide microring/racetrack resonators in silicon-on-insulator

In experiment, characteristics of silicon microring/racetrack resonators in submicron rib waveguides have been systematically investigated. It is demonstrated that only a transverse-electric mode is guided for a ratio of slab height to rib height h/H = 0.5. Thus, these microring/racetrack resonators can only function for quasi-transverse-electric mode, while they get rid of transverse-magnetic polarization. Electron beam lithography and inductively coupled plasma etching were employed and improved to reduce sidewall roughness for low propagation loss and high performance resonators. Then, the effects of waveguide dimensions, coupling region design, waveguide roughness, and oxide cladding for the resonators have been considered and analyzed.     

Stability of an Elastic System Consisting of a Ribbed Cylindrical Shell and Noncrossing Longitudinal Plates

The paper presents a method for stability analysis of an elastic system consisting of a ribbed cylindrical shell and noncrossing plates. The influence of the width and thickness of the plate on the buckling stresses and modes is analyzed     

SOI及GeSi/Si脊形光波导的模式与波导几何结构

用有效折射率方法对SOI（绝缘体上硅）及GeSi/Si脊形光波导的单模条件进行了模拟,与Soref的单模条件进行了比较,将两者与实验结果进行了比较,得到了与实验结果符合得非常好的单模条件。同时对多模波导进行了模拟,得到了波导承载一阶和二阶模的条件。     

Bandgap characteristics of the two-dimensional missing rib lattice structure

In this paper, the bandgap characteristics of a missing rib lattice structure composed of beam elements are investigated by using the Floquet-Bloch theorem. The tuning of the width and position of the bandgap is achieved by changing the local structural parameters, i.e., the rotation angle, the short beam length, and the beam thickness. In order to expand the regulation of the bandgap, the influence of the material parameters of the crossed long beams inside the structure on the bandgap is analyzed. The results show that the mass density and stiffness of the structure have significant effects on the bandgap, while Poisson's ratio has no effect on the bandgap. By analyzing the first ten bands of the reference unit cell, it can be found that the missing rib lattice structure generates multiple local resonance bandgaps for vibration reduction, and these bandgap widths are wider. The modal analysis reveals that the formation of the bandgap is due to the dipole resonance of the lattice structure, and this dipole resonance originates from the coupling of the bending deformation of the beam elements. In the band structure, the vibrational mode of the 9th band with a negative slope corresponds to a rotational resonance, which is different from that with the conventional negative slope formed by the coupling of two resonance modes. This study can provide a theoretical reference for the design of simple and lightweight elastic metamaterials, as well as for the regulation of bandgaps and the suppression of elastic waves.     

On the deformation of a ribbed cylindrical shell with initial deflection under dynamic loading

The finite-difference method with explicit time coordinate is used to study the dynamic stress-strain state of a cylindrical shell with ribs and initial deflections. A specific numerical example is considered to trace the time evolution of longitudinal and transverse displacements for different parameters of the initial deflection __________ Translated from Prikladnaya Mekhanika, Vol. 41, No. 12, pp. 61–66, December 2005.     

Wide-angle low-loss waveguide branching for integrated optics

A new wide-angle, low-loss, symmetrical Y-branch waveguide is proposed. The waveguide configuration utilizes ribs for lateral confinement in the planar guiding region underneath. This Y-branch structure can be fabricated easily without an additional process step. Together with a utilization of the multimode interference effect, a local decrease of the waveguide ridge in the wedge part of the Y-branch reduces the radiation loss. When proper@ designed, the proposed Y-branch has a radiation loss as low as 2.2 dB at a branch angle of 6° with the index difference (Δn/n) as small as 7.1 × 10^-4 at a wavelength of 870 nm in the TE fundamental mode as compared to 12.6 dB for a conventional Y-branch. The proposed method yields corresponding advantages for waveguide designs with a higher Δn/n ratio and can also be adapted in combination with S-branch designs.