SR型野外人工模拟降雨装置

SR型人工降雨装置是一种多喷头、多单元组合式的间歇降雨装置。选用目前国内外较理想的喷头 ,在喷头处辅以可改变喷头降水方式的机械传动装置 ,以间歇方式降雨来满足其降雨强度 ,雨滴直径大小及其分布与自然降雨相似。每个单元的有效降雨面积为 2 m× 5 m;如果 4个单元组合成 ,其长度可增加 4倍 ,有效降雨面积即 2 m× 2 0 m。装置采用轻型铝合金材料制成 ,结构简单 ,易于安装拆卸 ,适用于野外工作。

Single ridge waveguide electroabsorption modulated DFB laser for 2.5Gb/s transmission

In this paper we proposed a single ridge waveguide electroabsorption modulated distributed feedback laser (EML) for long-haul high-speed optical fiber communication system. This EML was successfully fabricated by two step metal organic vapor phase epitaxy (MOVPE) including selective area growth (SAG) and helium partially implantation. No obvious changes of the threshold current (< 0.2 mA), extinction ratio (< 0.1 dB), output power (< 0.2 dBm) and isolation resistance were achieved in the preliminary aging test. With 2.5 Gb/s NRZ modulation, no power penalty was observed after the optical signal was transmitted through 280 Km normal single mode fiber.