Preparation of activated carbon from coconut shell chars in pilot-scale microwave heating equipment at 60 kW

Experiments to prepare activated carbon by microwave heating indicated that microwave energy can decrease reaction temperature, save the energy and shorten processing time remarkably compared to conventional heating, owing to its internal and volumetric heating effects. The above results were based on the laboratory-scale experiments. It is desirable to develop a pilot-scale microwave heating equipment and investigate the parameters with the aim of technological industrialization. In the present study, the components and features of the self-invented equipment were introduced. The temperature rise curves of the chars were obtained. Iodine numbers of the activated carbons all exceed the state standard of China under the following conditions: 25 kg/h charging rate, 0.42 rev/min turning rate of ceramic tube, flow rate of steam at pressure of 0.01 MPa and 40 kW microwave heating power after 60 kW pre-activation for 30 min. Pore structure of the sample obtained at a time point of 46 h, which contained BET surface area, and pore size distributions of micropores and total pores, was tested by nitrogen adsorption at 77K.     

高价铬及双酚A在铁-乳酸体系中的同时光处理

研究了Fe(Ⅲ)-乳酸配合物体系同时对Cr(Ⅵ)的光还原及双酚A(BPA)的光氧化处理,考察了光源、初始pH值、Fe(Ⅲ)、乳酸盐、Cr(Ⅵ)及BPA初始浓度等因素对Cr(Ⅵ)及BPA光处理效率的影响。结果表明:光照条件下,铁-乳酸配合物能有效实现对六价铬及BPA的同时光处理。同一体系中,Cr(Ⅵ)的光还原快于BPA的光氧化,Fe(Ⅲ)初始浓度的增加可同时提高Cr(Ⅵ)的光还原效率和BPA的光氧化效率;Fe(Ⅲ)-乳酸盐配合物光解产生的Fe(Ⅱ)是Cr(Ⅵ)的主要还原剂,其次级光反应中产生的.OH是BPA的氧化剂。     

城市化对上海市五角场地区鸟类群落的影响

从时间及空间2个尺度上分析了城市化对上海市五角场地区鸟类群落的影响。结果表明，城市化过程中五角场地区的鸟类急剧减少，种类数从128种降至46种，科的数目也减少近半，其原因主要是城市化导致鸟类栖息地丧失和栖息环境的改变。农田水网生境的消失直接导致游禽在该区域的全部消失，80%游禽和农田村居鸟类也随之迁出该区域。现存的鸟类群落组成以林区鸟为主，其次是灌丛鸟，主要分布在公园，学校等有大片绿地的区域，其组成特点与现有的园林系统植物群落结构直接相关。城郊自然保护地段仍孕育了大量的鸟类，但由于现有的园林绿化系统结构单一，且彼此分离，呈片断化，难以承担向城内输送物种的任务。一个具有复层混交立体且空间上连续的园林绿地系统是维持城区鸟类多亲性的物质基础。     

Removal of runoff pollutants by construction waste bricks-based bioretention facilities

Journal of Material Cycles and Waste Management - Construction waste bricks (CWB) were simply pre-treated as fillers applied in different filler layers of bioretention facility. The removal effect...     

Exposure characteristics of phthalate metabolites among the Zunyi cohort of pregnant women in Southwest China

Environmental Science and Pollution Research - Reported evidence has increasingly indicated that exposure to phthalates can cause adverse pregnancy outcomes. However, phthalate exposure levels...     

Effect of streambed substrate on macroinvertebrate biodiversity

Macroinvertebrates are important components of stream ecosystems, and are often used as indicator species for the assessment of river ecology. Numerous studies have shown that substrate is the primary physical environmental variable affecting the taxa richness and density of macroinvertebrates. The aim of this work is to study the effects of the characteristics of streambed substrate, such as grain size, shape, and roughness, on the composition and biodiversity of macroinvertebrates. A field experiment was done on the Juma River, a second-order mountain stream in northern China. Substrata of cobbles, hewn stones, pebbles, coarse sand, and fine sand were used to replace the original gravel and sand bed in a stretch of 30 m in length. The sampling results indicated that the macroinvertebrate assemblage is significantly affected by the grain size, porosity and interstitial dimension of the substrate, while it is rarely affected by the shape and the surface roughness of the experimental substrata. Macroinvertebrate compositions in cobbles and hewn stones were stable and changed least over time. The taxa richness and density of individuals in the substrata of cobbles, hewn stones, and pebbles are much higher than in those of the coarse sand and fine sand.     

一种防范雷电灾害的方法

地震台站的防霄问题显得越来越重要。陕西水动态观测周至井和3原井在数字化改造后，至今没有遭受过一次雷击。本文介绍了这两个台在防范雷电危害方面的方法和措施。实践证明在安装仪器时只要严格按照规范要求实施，就能最大限度地避免雷电的灾害。     

汶川地震前周至深井观测数据的异常特征

分析了汶川地震前后周至台流体数据异常特征,特别对该台水位、流量数字化资料分钟值的的毛刺现象进行了深入研究,并用水位的整点值做了潮汐变化分析和小波分析.结果表明,汶川地震前,该台流体观测有一定的前兆显示,为流体学科的异常判定提出了新的思路.     

Fe(Ⅲ)-酒石酸盐配合物体系的光解特性

以Fe(Ⅲ)-酒石酸配合物体系光化学过程中产生的Fe(Ⅱ)和.OH为主要检测对象,探讨了Fe(Ⅲ)-酒石酸配合物体系光化学反应的基本规律及影响因素。结果表明,体系的光化学过程能产生Fe(Ⅱ)和.OH;产生Fe(Ⅱ)的速率远高于产生.OH的速率;Fe(Ⅱ)生成浓度在pH 3.50时最大,.OH则在pH 3.00时最大;配合物的光化学过程中会伴随pH的升高;在照度为3.6×103Lux的日光灯照射下,Fe(Ⅲ)-酒石酸盐配合物初级光解的速率常数为2.1×10-3S-1;Fe(Ⅱ)是高价重金属的主要还原剂,.OH是有机物的主要氧化剂。