基于EPP协议的便携机数据采集系统

设计了基于EPP协议的便携机数据采集系统 ,给出了技术解决方案。方案具有软硬件设计简捷、无需插卡等优点 ,可使外设工作于PC并行口的多种模式下。解决了线阵CCD图像采集系统与笔记本电脑之间的数据通讯 ,达到了便携数据采集的目的。     

Short-range order in some polymer melts from X-ray diffraction

Wide-angle X-ray diffraction measurements were performed on polymer melts of isotactic and syndiotactic polypropylene (IPP and SPP), poly(ethylenepropylene) (PEP), polystyrene (PS), polyisobutylene (PIB), and polyethylene (PE), to study the dependence of the short-range structure of polymer liquids on chain architecture. Total structure functions, which comprise intra- and intermolecular contributions, were derived from the scattering data. The trivial Fourier components of the intramolecular structure (C(SINGLE BOND)>C ≃ 1.54 Å and C(SINGLE BOND)C(SINGLE BOND)C ≃ 2.55 Å) were subtracted from the total structure functions. The remaining functions contain only those intramolecular contributions dependent on the chain's conformational degrees of freedom, plus the intramolecular contributions. The structural differences between the polymers in momentum space are discerned only when the trivial components are subtracted. This subtraction also reduces the effects of truncation errors on Fourier transformation to real space. The short-range structure of PIB appears very different compared to all the others, which correlates with anomalies in a number of physical properties for this polymer. © 1996 John Wiley & Sons, Inc.     

Analysis,design and simulation of MIM plasmonic filters with different geometries for technical parameters improvement

In this paper, four optical filter topologies based on metal–insulator–metal waveguides are proposed and the designed structures are investigated numerically using finite-difference timedomain method. Triangular-shaped adjunctions have been added to the filter structures to improve their transmission spectrum. These improved structures consist of air as the insulator and silver as the metal. The relative permittivity of metal has been described via the Drude,Drude–Lorentz, and Palik models. The first filter's transmission spectrum shows an acceptable transmittance. In the second optimized filter, the transmission spectrum has been improved. The transmittance spectrum can be tuned through adjusting the edge of the triangle in these four optimized filters. As a result, the bandwidths of resonance spectra can be adjusted. The theory of such tapered structures will be investigated by the tapered transmission line and will be solved with the transfer matrix method. This method shows a better performance and higher transmission efficiency in comparison with the basic structures. On the other hand, the final filter has been chosen as the best one because of its hexagonal resonator. The main reason for having a better result is due to a longer interaction length in comparison with the circular resonator. This in turn creates much better energy coupling and results in higher transmission.     

声表面波MIM隧道发光二极管

我们在研究MIM隧道发光结(金属-绝缘层-金属)的过程中,首次以表面声波代替表面随机粗糙度的作用,将MIM结制作在声表面波场中,结果使结的发光效率、发光强度、稳定性、均匀性都有改善.本文介绍了结的基本结构,基本工艺,阐明了结的发光机理,讨论了结的Ⅰ-Ⅴ特性曲线和光谱曲线,根据结具有显著的负阻现象,我们设计出了一种新型的开关器件.     

Comprehensive analysis of photonic nanojets in 3D dielectric cuboids excited by surface plasmons

In this paper we study the excitation of photonic nanojets (PNJ) in 3D dielectric cuboids by surface plasmons at telecommunication wavelengths. The analysis is done using the effective refractive index approach. It is shown that the refractive index contrast between the regions with and without cuboid should be roughly less than 2 in order to generate jets at the output of the cuboid. The best performance at λ₀ = 1550 nm is obtained when the height of the cuboid is 160 nm producing a jet just at the output interface with a subwavelength resolution of 0.68λ₀ and a high intensity enhancement (×5) at the focus. The multi‐wavelength response is also studied demonstrating that it is possible to use the proposed structure at different wavelengths. Finally, the backscattering enhancement is numerically evaluated by inserting a metal particle within the PNJ region, demonstrating a maximum value of ～2.44 dB for a gold sphere of radius 0.1λ₀.

     

增强金属-氧化物-金属隧道结的光发射

本文报道通过改进制作工艺将A1-A12O3-Au隧道结的耐压增加到5.3V,发光外量子效率增加到8.2×10-4,均高过迄今见到的关于该类结的最高耐压和最高效率的报道。我们观测到了该发光结上的Au膜厚度对发射光谱形状的影响,并对此作出了解释;还对该光谱中的截止频率和峰值的存在给出了理论解释。     

The connes spectrums of certain finite non-abelian groups

In this article, we investigate when every simple module has a projective (pre)envelope. It is proven that (1) every simple right R-module has a projective preenvelope if and only if the left annihilator of every maximal right ideal of R is finitely generated; (2) every simple right R-module has an epic projective envelope if and only if R is a right PS ring; (3) Every simple right R-module has a monic projective preenvelope if and only if R is a right Kasch ring and the left annihilator of every maximal right ideal of R is finitely generated.