The catalytic performance of Cu46Zr47-xAl7Yx amorphous ribbons in the degradation of AO II dye wastewater

Environmental Science and Pollution Research - Metallic glasses (MGs) with unique disordered atomic stacking structures exhibit excellent catalytic performance in wastewater treatment. The...     

On the effect of Fe(III) on proliferation of Microcystis aeruginosa at high nitrate and low chlorophyll condition

The impact of Fe concentrations on the growth of Microcystisaeruginosa in aquatic systems under high nitrate and low chlorophyll conditions was studied. The responses of cell density, total and cell chlorophyll-a intracellular Fe content and organic elemental composition of M. aeruginosa to different concentration gradients of Fe(III) in the solutions were analysed. The results showed that the proliferation speeds of M. aeruginosa were: (1) decelerated when the Fe(III) concentration was lower than 50 μg/L in the solutions, (2) promoted and positively related to the increase of Fe(III) concentration from 100 to 500 μg/L in the solutions over the experimental period, and (3) promoted in the early stage but decelerated in later stages by excess adsorption of Fe by cells when the Fe(III) concentration was higher than 500 μg/L in the solutions. The maximum cell density, total and cell chlorophyll-a were all observed at 500 μg Fe(III)/L concentration. The organic elemental composition of M. aeruginosa was also affected by the concentration of Fe(III) in the solutions, and the molecular formula of M. aeruginosa should be expressed as C_7–7.5H₁₄O_0.8–1.3N_3.5–5 according to the functions for different Fe(III) concentrations. Cell carbon and oxygen content appeared to increase slightly, while cell nitrogen content appeared to decrease as Fe(III) concentrations increased from 100 to 500 μg/L in the solutions. This was attributed to the competition of photosynthesis and nitrogen adsorption under varying cell Fe content.     

海洋功能区划保留区管控要求解析及政策建议

本文基于保留区选划的原因和分类,结合新一轮全国和省级海洋功能区划编制,汇总和比较全国、省级保留区管控规定,分析了目前各省保留区个数、面积、岸线长度、离岸距离等设置情况。据此,依据保留区内涵将保留区划分为五类,即功能待定区、发展预留区、整治修复预留区、保护缓冲区以及特殊功能预留区,分别提出五类保留区的使用管理要求和环境保护要求。最后,文章从保留区用海现状处理方式、开发利用条件、用海活动管理等方面提出政策建议。总体来说,保留区不允许随意利用但并不完全禁止利用,在不改变海域自然属性的前提下,当用海活动符合保留区用途及环境保护要求,不影响周边海域功能正常发挥的情况下允许进行开发利用。     

因子分析在黄河上游干流地区滑坡灾害中的应用

黄河上游地区干流滑坡灾害频繁发生,造成了严重的经济损失和人员伤亡。对该区滑坡灾害进行研究,对于指导该区的抗灾、减灾和预防工作意义重大。采用遥感技术和野外采样实测,获取了研究区的129处滑坡灾害数据,进而对滑坡灾害影响因素进行了因子分析。通过因子分析,得到公因子,并对公因子命名。在此基础上,计算了因子得分及综合得分,并对其进行了排序。研究结果表明:灾害数据变量之间有较强的相关性,滑坡发生主要受到滑体标高因子、滑体外形因子、地表因子、环境因子和滑体性质5个公共因子的影响。滑体标高、环境特征和滑体性质对滑坡的影响较大,滑体外形因素和地表因素对滑坡发生的影响相对较小。     

降雨对华北土石山区侧柏林土壤呼吸的影响

采用碱液吸收法(AA法)对北京西部山区不同降雨处理的典型侧柏林的土壤呼吸速率做了测定。同时测定了土壤呼吸测定点的土壤温度、土壤水分及气温和湿度等气象因子。结果表明5 mm、10 mm、20 mm降雨处理对侧柏林土壤呼吸都有促进作用,而50 mm降雨处理以及50 mm频率降雨对土壤呼吸的促进作用不明显。研究发现降雨导致土壤含水量升高并造成土壤呼吸的温度敏感性降低,Q10为1.1左右。通径分析的结果表明7 cm土壤温度、空气温度、大气相对湿度对各降雨处理的土壤呼吸速率的直接效应是最为显著的,其中对土壤呼吸影响最大的因素是温度。     

石化企业环境因素识别与评价

介绍了环境因素识别与评价的基本步骤和内容,探讨了重要环境因素确定、更新方法及控制措施。     

Photocatalytic activity of Fe-doped CaTiO3 under UV-visible light

The photocatalytic degradation of methylene blue（MB） over Fe-doped CaTiO3 under UV-visible light was investigated. The as-prepared samples were characterized using X-ray diffraction（XRD）, scanning electron microscope（SEM） equipped with an energy dispersive spectrometer（EDS） system, Fourier transform infrared spectra（FT-IR）, and UV-visible diffuse reflectance spectroscopy（DRS）. The results show that the doping with Fe significantly promoted the light absorption ability of CaTiO3 in the visible light region. The Fe-doped CaTiO3 exhibited higher photocatalytic activity than CaTiO3 for the degradation of MB.However, the photocatalytic activity of the Fe-doped CaTiO3 was greatly influenced by the calcination temperature during the preparation process. The Fe-doped CaTiO3 prepared at500°C exhibited the best photocatalytic activity, with degradation of almost 100% MB（10 ppm）under UV-visible light for 180 min.     

淮河流域安徽省2007年的暴雨洪水特性分析

为系统研究淮河流域安徽省2007年的暴雨洪水特征,对降雨过程和暴雨频率进行了分析.结果表明,2007年的主要暴雨特性是梅雨时间长,梅雨量淮河以北多、淮河以南少,降雨时间长、强度大、范围广,降雨时空分布不均.通过淮河干支流洪水过程和淮河干流洪水特征值的分析,结果表明,2007年的主要洪水特性是水位高、流量大,高水位持续时间长,干支流洪水并发,洪水组合恶劣.虽然淮河干流经过了大规模的治理,2007年洪水期间沿淮启用了蒙洼等9个行蓄洪区,但淮河中游仍然持续高水位,润河集至汪集段超过历史最高洪水位,表明淮河流域洪水灾害较为严重,需要进一步研究如何科学调度沿淮行蓄洪区、如何协调淮河与洪泽湖之间的关系,以便更好地进行该流域的洪水管理.     

Heterogeneous UV/Fenton degradation of bisphenol A catalyzed by synergistic effects of FeCo2O4/TiO2/GO

A new method for bisphenol A (BPA) degradation in aqueous solution was developed. The characteristics of BPA degradation in a heterogeneous ultraviolet (UV)/Fenton reaction catalyzed by FeCo₂O₄/TiO₂/graphite oxide (GO) were studied. The properties of the synthesized catalysts were characterized using scanning electron microscopy, X-ray diffraction, and vibrating sample magnetometry. FeCo₂O₄ and TiO₂ were grown as spherical shape, rough surface, and relatively uniform on the surface of GO (FeCo₂O₄/TiO₂/GO). Batch tests were conducted to evaluate the effects of the initial pH, FeCo₂O₄/TiO₂/GO dosage, and H₂O₂ concentration on BPA degradation. In a system with 0.5 g L⁻¹ of FeCo₂O₄/TiO₂/GO and 10 mmol L⁻¹ of H₂O₂, approximately 90 % of BPA (20 mg L⁻¹) was degraded within 240 min of UV irradiation at pH 6.0. The reused FeCo₂O₄/TiO₂/GO catalyst retained its activity after three cycles, which indicates that it is stable and reusable. The heterogeneous UV/Fenton reaction catalyzed by FeCo₂O₄/TiO₂/GO is a promising advanced oxidation technology for treating wastewater that contains BPA.

     

摆管淋水试验装置的校准方法探讨

文中简述了摆管淋水试验装置的基本结构及其常见的校准方式,对其中的“摆角校准”这一技术难点提出了可行的解决方案并作了较详尽的说明分析。