Simultaneous adsorption and degradation of γ-HCH by nZVI/Cu bimetallic nanoparticles with activated carbon support

Cu amended zero valent iron bimetallic nanoparticles were synthesized by doping Cu on the surface of iron. They were incorporated with granular activated carbon (AC) to prepare supported particles (AC-Fe⁰-Cu), which were used to remove γ-HCH. Cu on the surface of iron enhanced the dechlorination activity of Fe⁰. The dechlorination rate constant (k_obs) increased with the Cu loading on the surface of iron and the maximum was achieved with 6.073% Cu. AC as a support was effective for increasing the dispersion of the nanoparticles and avoiding the agglomeration of the metallic nanoparticles. The simultaneous adsorption of γ-HCH on AC accelerated the degradation rate of γ-HCH by the bimetals. After reaction for 165 min, around 99% of γ-HCH was removed by the solids of AC-Fe⁰-Cu. In addition, AC could adsorb the degradation products. The degradation of γ-HCH was mainly through dehydrochlorination and dichloroelmination based on the intermediate products detected by GC/MS.     

Light absorption properties and potential sources of brown carbon in Fenwei Plain during winter 2018–2019

A distinctive kind of organic carbon aerosol that could absorb ultraviolet-visible radiation is called brown carbon (BrC), which has an important positive influence on radiative budget and climate change. In this work, we reported the absorption properties and potential source of BrC based on a seven-wavelength aethalometer in the winter of 2018–2019 at an urban site of Sanmenxia in Fenwei Plain in central China. Specifically, the mean value of BrC absorption coefficient was 59.6 ± 36.0 Mm^?1 at 370 nm and contributed 37.7% to total absorption, which made a significant impact on visibility and regional environment. Absorption coefficients of BrC showed double-peak pattern, and BrC had shown small fluctuations under haze days compared with clean days. As for the sources of BrC, BrC absorption coefficients expressed strong correlations with element carbon aerosols and primary organic carbon aerosols, indicating that most of BrC originated from primary emissions. The linear correlations between trace metal elements (K, As, Fe, Mn, Zn, and Pb) and BrC absorption coefficients further referred that the major sources of BrC were primary emissions, like coal burning, biomass burning, and vehicle emissions. The moderate relationship between BrC absorption coefficients and secondary organic aerosols suggested that secondary production of BrC also played an important role. The 120 hr backward air mass trajectories analysis and concentration-weighted trajectories analysis were also used to investigate potential sources of BrC in and around this area, which inferred most parts of BrC were derived from local emissions.     

盐龙湖水源生态净化系统FG和MBFG演替特征及水质响应性评价

为探究水源生态净化系统水质净化及浮游植物控制效能,并评价FG(functional group,FG)和MBFG(morphology-based functional group,MBFG)两种功能群对水源生态净化系统内部环境以及水质响应的有效性,于2018年夏季对盐龙湖生态净化系统各单元出水水质和浮游植物功能群进行监测分析.结果表明,盐龙湖生态净化系统能够有效净化水质,进水总磷、总氮、溶解氧和浊度的平均值分别为0.20 mg·L^-1、 1.91 mg·L^-1、 2.88 mg·L^-1和60.23 NTU,经系统处理后分别为0. 09 mg·L^-1、 0.95 mg·L^-1、 6.26 mg·L^-1和39.53 NTU.同时,系统内部水质的空间分布具有异质性,其中溶解氧(DO)、酸碱度(pH)和浊度的空间差异显著(P<0.001).盐龙湖生态净化系统在出水处于轻度富营养状态下仍能够有效控制浮游植物密度(4.42×10⁵～4.3...     

Assessment of coal spontaneous combustion index gas under different oxygen concentration environment: an experimental study

Environmental Science and Pollution Research - Oxygen plays a crucial role in coal spontaneous combustion (CSC), and the magnitude of oxygen concentration determines the oxidation reaction...     

Reinforcing Paper Strength with High Viscosity Aminated Cellulose Nanocrystal by Forming Nanocrystal Networks

Journal of Polymers and the Environment - Higher tensile and bursting strength are paramount concerns in paper-based packaging materials. Herein, the aminated cellulose nanocrystal (A-CNC) was...     

钻井废水酸化中和预处理研究

针对钻井废水悬浮物和CODCr含量高的污染特征,对其酸化中和预处理的可行性进行了实验研究,并对其作用机理进行了探讨,以浓H2SO4 调节pH至1.5,加入石灰乳中和使 pH为9,可使CODCr的去除率达到50%,悬浮物的去除率达到80%.处理可在废水池内进行,给下一步利用装置进行混凝处理创造了条件。