富裕县杨树害虫发生危害情况及综合治理对策

介绍了富裕县杨树害虫发生危害情况,2004年有害生物普查中杨树蛀干害虫侵害面积达11333hm2,食叶害虫每年发生面积达3333hm2以上.针对这些虫害,提出了加强监测、强化检疫、清理虫源木、化学防治等治理对策.     

厌氧反应器系统动力学模型构建方法学研究

以系统动力学的基本概念、方法为基础提出了存在于变量之间的3种基本关系模式,并在此基础上提出针对复杂系统的分块建模理论.将以葡萄糖为进水基质的厌氧反应器划分为3个子系统.确定了该系统的系统结构图,在此基础上构建厌氧消化系统的SD模型.根据分块建模的优势及特点,对模型中的3个子系统采用不同的计算方式,通过对比模拟结果表明,SD模型静态模拟结果与实验数据、传统结构模型模拟结果之间的误差<10%,动态模拟结果与实际趋势一致,说明SD模型的模拟结果是可信的.根据其特性,对取消物化子系统的简化模犁的模拟结果进行分析,表明根据不同的研究目的,选择合适的模型结构是必要的,采用系统动力学的分块建模方法有利于模型的简化与升级、减少计算量、提高模型的计算速度.     

Fenton法处理类长填龄渗滤液的氧化和絮凝作用

采用Fenton法对难降解的类长填龄渗滤液进行处理,考察其氧化和絮凝作用对有机物去除的贡献. 结果表明:以COD_Cr去除率最大为目标,试验在最优条件下,c(H₂O2)/c(Fe2+)为7.0,Fe2+投加量(c(Fe2+))为60　mmol/L,pH为3.0,此时COD_Cr总去除率为60%;其中氧化作用去除率为44%,氧化和絮凝作用的效率比为2.7. c(H₂O₂)/c(Fe2+),c(Fe2+)和pH的变化对氧化和絮凝作用有明显影响,氧化作用对COD_Cr去除率随H₂O₂投加量增大而增大.絮凝作用对COD_Cr的去除率不仅受Fe2+投加量直接影响,随其增加而增大;还间接受氧化作用去除率影响,氧化作用去除率越大,剩余有机物大分子所占比例降低,絮凝作用对有机物的去除率越低.      

光度法测定水中己二胺

本文报道了在碱性介质中,沸水浴条件下,己二胺与２,４二硝基氯苯反应生成黄色的１,６二（２,４二硝基苯胺）己烷化合物,用氯仿萃取后于波长４２０ｎｍ处,用２０ｍｍ比色皿比色测定。文中对碱的用量,反应温度及时间,显色剂用量及萃取效率等进行了较详细研究,确定了最佳实验条件并进行了废水样品分析,结果满意。     

甲烷气体标准样品的研制

对称量制备甲烷气体标准样品的制备方法进行了详细研究 ,对可能引起甲烷量值不确定度的各种误差来源进行了分析。文中提出的甲烷气体标准样品制备方法具有很好的重现性 ,所制备的甲烷气体标准样品具有良好的压力稳定性并已能在三种气瓶中稳定保存 1 8个月 ,其量值准确、可比 ,并已在全国环境监测网试用。     

二氧化硫(高压)气体标准样品的研制

文章对高压气瓶中二氧化硫气体标准样品的制备方法进行了研究 ,对各种可能影响二氧化硫气体标准样品量值准确性的因素进行了分析。所制备的 2 0 .2 μmol/ mol二氧化硫气体标准样品的不确定度仅为 1 .4 % ,且具有良好的压力稳定性并能稳定保存 2 0个月     

Research on the effects of diesel engine exhaust transport distance on particulate microstructure

This study aims to reveal the evolutionary process of particles during the diesel exhaust transport process and to further understand the effects of diesel exhaust transport distance (D_ET) on a particulate microstructure. Specifically, the micromorphological, particle size distribution, and aggregate characteristics of particles as well as the variation of the structural characteristics of elementary carbon particles (ECPs) as D_ET changed were examined using an engine exhaust particle size spectrometer, a high-resolution transmission electron microscopy system, and a small-angle X-ray scattering system. The results show the following: As D_ET increased, the chains gradually lengthened, the extent of accumulation and stacking increased, and a number of clusters gradually rose. The average particle diameter increased from 23.1 nm at 0 m to 92.7 nm at 3 m. In addition, as D_ET increased, the number of accumulation-mode particles, the number of folded, curved carbon layers in the inner core of carbon particles, and the disorderliness of carbon layers in the outer shell of carbon particles all increased. Moreover, the boundary between the inner core and the outer shell became increasingly obscure. As D_ET increased, there was a gradual decrease in the difference in electron density between particles, and the fractal dimensionality of the distribution, average cross-sectional size, radius of gyration, and axial length of pores were, respectively, 33.3%, 40%, 38.2%, and 50.3% less at 3 m than at 0 m. Besides that, the number of small (< 3 nm) pores gradually increased, and the number of large (> 10 nm) pores gradually decreased. Overall, as D_ET increased, pore size and number decreased. There was a gradual increase in the number of folded and curved carbon layers in the inner core of ECPs and an increase in the disorderliness of carbon layers in their outer shell as D_ET increased. Furthermore, the boundary between the inner core and the outer shell became increasingly obscure as D_ET increased. The crystallite size of ECPs decreased from 1.365 nm at 0 m to 1.098 nm at 3 m. This suggests that the number of continuously arranged carbon atoms decreased, the arrangement of carbon atoms was more disorderly, and the degree of graphitization decreased. As D_ET increased, there was a gradual increase in the interlayer spacing and curvature of ECPs. This suggests that increasing D_ET led to a more disorderly distribution of electron orbitals inside the carbon layers, less electron resonance stability in the carbon layers, greater oxidative activity of ECPs, and greater inherent oxidative capacity of particles.

     

Phosphorus removal from wastewater by waste concrete: influence of P concentration and temperature on the product

Environmental Science and Pollution Research - This study investigated the feature of phosphorus uptake by low-cost waste concrete. Adsorption isotherms, metal dissolution, influence of P...     

贡嘎山高山生态系统观测试验站——“中国生态系统研究网络”站之一

贡嘎山高山生态系统观测试验站代表青藏高原东缘面积达60万平方公里的高山深谷山地生态系统类型。贡嘎山东坡从河谷到山顶可明显地分出六个山地自然垂直带,每一个带内又可分出若干亚带。自然生态系统类型多样,保存完好,海拔2000米以上基本处于未开发的原始状态,具有自然生态系统原生性强的显著特点,是开展山地生态系统观测试验的理想场地。