Ultrahigh Extinction Ratio Leaky-Guided Hollow Core Fiber Mach-Zehnder Interferometer Assisted by a Large Core Hollow Fiber Beam Splitter.

We proposed a novel fiber Mach-Zehnder interferometer (FMZI) that can perform an ultrahigh extinction ratio (ER), ultracompact, and ultra-broadband interference characteristics. The FMZI structure is based on an extremely tiny hollow core fiber (HCF) with a small diameter of 10 μm (named HCF) connected with a beam splitter of a large core of 50 μm HCF (named HCF). The refractive index (RI) of the air core is lower than that of the HCF cladding; a leaky-guided fiber waveguide (LGFW) occurs in such a short-section HCF waveguide to simultaneously have the core and cladding modes.

[Advanced Treatment of Tail Water Using Pilot-scale Horizontal and Vertical Subsurface Flow Constructed Wetlands in Low-temperature Seasons].

There were significant differences in the working efficiency and mechanism of constructed wetlands between low temperature and suitable temperature conditions. This study designed a horizontal subsurface flow constructed wetland (HFCW) and a vertical subsurface flow constructed wetland (VFCW) to explore their performance differences in advanced treatment of sewage based on contaminant degradation analysis including the removal of organic matters, total nitrogen (TN), and total phosphorus (TP), as well as the analysis of microbial community structure. The results showed that when the COD concentration of influent was between 37.

[Pollution Load Characteristics of Runoff from Urban Roofs of Different Materials].

It is of great significance to analyze the runoff pollution load characteristics of different roof materials to improve the estimation accuracy of urban non-point source pollution loads. Yangzhou City was selected as the study area. There, three types of roofs were chosen for rainfall-runoff monitoring, including a Chinese style tile roof, cement tile roof, and concrete flat roof.