Light Scattering by Cylindrical Fibers with High Aspect Ratio Using the Null‐Field Method with Discrete Sources

The problem of computing light scattering by cylindrical fibers with high aspect ratio in the framework of the Null‐Field method with discrete sources is treated. Numerical experiments for investigating the scattering properties of two fiber geometries are performed using distributed spherical vector wave functions as discrete sources.     

下一代测试系统化解闪存复杂性问题

随着移动电话和掌上计算机等个人电子设备需求的驱动,闪存器件已经通过快速发展,迈上了更高的容量和性能水平.今天,半导体制造厂商发现,对更为先进的闪存产品的需求与日俱增,其交付方式或为独立的闪存器件,或者作为拥有逻辑电路的内核,嵌入单芯片器件中,或与微控器、逻辑或静态内存共同出现在芯片中.对闪存制造商来说,要想在这些高度竞争的市场中取得成功,就要求它们能够严格控制测试成本,尽管器件本身正日趋复杂.由于闪存在大小尺寸、速度和复杂性方面都在不断增加,制造商正在寻求更为成本有效的单次插入测试解决方案,并希望其能够解决目前正在浮现的测试挑战.随着新测试技术的出现,制造商可以运用成本经济的下一代测试平台有效解决日益严峻的闪存复杂性问题.     

A low-noise fixed-tuned 300-360-GHz sub-harmonic mixer using planar Schottky diodes

This letter presents the design and fabrication of a low-noise fixed-tuned 300-360-GHz sub-harmonic mixer, featuring an anti-parallel pair of planar Schottky diodes fabricated by the University of Virginia and flip-chipped onto a suspended quartz-based microstrip circuit. The mixer exhibits a double side band (DSB) equivalent noise temperature lower than 900K over 18% of bandwidth (300-360-GHz), with 2 to 4.5mW of local oscillator (LO) power. At room temperature, a minimum DSB mixer noise temperature of 700K and conversion losses of 6.3dB are measured at 330GHz.     

Preparative separation and analysis of the enantiomers of [3H]Abbott-69992, an HIV anti-infective nucleoside, by ligand-exchange high-performance liquid chromatography.

Several chiral stationary phases (CSPs) were examined to separate the enantiomers of A-69992, a chiral HIV anti-infective nucleoside. The only CSP found to be effective was Nucleosil Chiral-1, a ligand-exchange CSP, which was used to prepare microgram amounts of the enantiomers of high optical purity. This appears to be the first separation of the enantiomers of a nucleoside by chiral high-performance liquid chromatography.