水处理滤料润湿性的实验研究

基于Washburn方程用亲油亲水比(LHR)比较了无烟煤、沸石和石英砂滤料对油的润湿选择性,并对其表面结构进行了表征.结果表明,无烟煤、沸石和石英砂的LHR值依次为2.41、0.64和0.65,沸石和石英砂的亲水性明显好于无烟煤,而无烟煤的亲油性好于沸石和石英砂.这主要取决于滤料的表面化学组成,同时与其表面形貌有一定的关系,与SEM、XPS、FTIR分析结果基本吻合.     

“A Short Burst of Inconsequential Information:” Networked Rhetorics,Avian Consciousness,and Bioegalitarianism

This essay uses the concept of “avian consciousness” to reconsider assumptions about human communication and theorize networked rhetorics. By adopting an ornithomorphic frame, I critically read Don DeLillo's The Body Artist as an exploration of overlaps between human and avian consciousness. I then argue that avian consciousness provides a richer metaphor for understanding networked rhetorics than autistic consciousness, which is an increasingly dominant trope for explaining interaction with digitally networked media. I explore how Twitter, explicitly modeled on avian communication, can be understood as circulating information in ways analogous to the contact and assembly calls of birds. The essay concludes by noting that seeing avian features in human communication diminishes the perceived gap between human and nonhuman animal, holding out hope for a more bioegalitarian relationship between species.     

论新时期的环境新闻宣传工作

近年来,环境问题变得更加复杂,环境新闻宣传作为环保工作对外的窗口仍停留在固有的模式,面临着环境形势严峻、信息传播迅猛发展等诸多挑战。从新闻制度、舆论引导、宣传平台、网络舆情和环境突发事件等方面提出了新时期环境新闻宣传工作的对策建议。     

Effect of goethite coating and humic acid on the transport of bacteriophage PRD1 in columns of saturated sand

The transport of bacteriophage PRD1, a model virus, was studied in columns containing sediment mixtures of quartz sand with goethite-coated sand and using various solutions consisting of monovalent and divalent salts and humic acid (HA). Without HA and in the absence of sand, the inactivation rate of PRD1 was found to be as low as 0.014 day(-1) (at 5+/-3 degrees C), but in the presence of HA it was much lower (0.0009 day(-1)), indicating that HA helps PRD1 to survive. When the fraction of goethite in the sediment was increased, the removal of PRD1 also increased. However, in the presence of HA, C/C0 values of PRD1 increased by as much as 5 log units, thereby almost completely eliminating the effect of addition of goethite. The sticking efficiency was not linearly dependent on the amount of goethite added to the quartz sand; this is apparently due to surface charge heterogeneity of PRD1. Our results imply that, in the presence of dissolved organic matter (DOM), viruses can be transported for long distances thanks to two effects: attachment is poor because DOM has occupied favourable sites for attachment and inactivation of virus may have decreased. This conclusion justifies making conservative assumptions about the attachment of viruses when calculating protection zones for groundwater wells.     

一维脉冲波透过压电介质摩擦接触界面的传播

以压电材料为核心的结构和元件在装置中,总是和其他材料组合在一起,常用来传导表面波或承受动荷载,界面是其中的重要组成部分。当扰动很强时,会引起接触界面的局部滑移和分离,对结构安全产生威胁。笔者对一维脉冲波透过横观各向同性压电介质摩擦接触界面的传播进行了研究。利用Fourier分析的方法,将混合边值问题化为非线性代数方程组,通过迭代修正,确定了界面上分离、滑移和粘着3种区域的分布范围,同时计算了界面剪力和相对滑移速度的分布。笔者进一步丰富了压电弹性波动理论,利用波所携带的力学或电学信息,可望无损探测界面的接触状态及接触力等参量,对结构的安全评估与寿命预测具有重要的理论价值与实际意义。     

Humic acid transport in saturated porous media: Influence of flow velocity and influent concentration

Understanding the transport of humic acids（HAs） in porous media can provide important and practical evidence needed for accurate prediction of organic/inorganic contaminant transport in different environmental media and interfaces. A series of column transport experiments was conducted to evaluate the transport of HA in different porous media at different flow velocities and influent HA concentrations. Low flow velocity and influent concentration were found to favor the adsorption and deposition of HA onto sand grains packed into columns and to give higher equilibrium distribution coefficients and deposition rate coefficients, which resulted in an increased fraction of HA being retained in columns.Consequently, retardation factors were increased and the transport of HA through the columns was delayed. These results suggest that the transport of HA in porous media is primarily controlled by the attachment of HA to the solid matrix. Accordingly, this attachment should be considered in studies of HA behavior in porous media.     

Mobilizing Facebook Users against Facebook's Energy Policy: The Case of Greenpeace Unfriend Coal Campaign

This research analyzes Greenpeace International Unfriend Coal protest campaign against Facebook's energy policy (2010–2011), as a case study in the organization's approach to campaigning on climate change issues. In the context of Greenpeace protest history and social movement research, we focus on the online mobilization tactics used by Greenpeace, and how they differed from previous campaign practices. The findings are based on a content analysis of all statuses posted on the campaign Facebook page (N = 119), and six semi-structured interviews with key Greenpeace personnel. The analysis reveals that Greenpeace used Facebook extensively both for disseminating information and context about the campaign, and as a platform for mobilizing and facilitating broad public engagement. Greenpeace seized the affordances of the Facebook platform and introduced new means of online mobilization and engagement. These e-tactics proved effective for engaging diverse transnational supporters in the campaign. The implications for environmental non-governmental organizations and the broader environmental movement are discussed.     

水处理生物填料发展现状与趋势

生物填料是水处理中的核心技术之一,对水处理领域有十分重要的意义。本文综述了水处理领域填料的发展现状,指明了填料的发展趋势,对亲水性、生物亲和性、磁效应填料的特点做出了阐述,给出了今后填料的发展方向。     

Porous media grain size distribution and hydrodynamic forces effects on transport and deposition of suspended particles

The effects of porous media grain size distribution on the transport and deposition of polydisperse suspended particles under different flow velocities were investigated. Selected Kaolinite particles(2–30 μm) and Fluorescein(dissolved tracer) were injected in the porous media by step input injection technique. Three sands filled columns were used: Fine sand,Coarse sand, and a third sand(Mixture) obtained by mixing the two last sands in equal weight proportion. The porous media performance on the particle removal was evaluated by analysing particles breakthrough curves, hydro-dispersive parameters determined using the analytical solution of convection–dispersion equation with a first order deposition kinetics, particles deposition profiles, and particle-size distribution of the recovered and the deposited particles. The deposition kinetics and the longitudinal hydrodynamic dispersion coefficients are controlled by the porous media grain size distribution. Mixture sand is more dispersive than Fine and Coarse sands. More the uniformity coefficient of the porous medium is large, higher is the filtration efficiency. At low velocities, porous media capture all sizes of suspended particles injected with larger ones mainly captured at the entrance.A high flow velocity carries the particles deeper into the porous media, producing more gradual changes in the deposition profile. The median diameter of the deposited particles at different depth increases with flow velocity. The large grain size distribution leads to build narrow pores enhancing the deposition of the particles by straining.     

磁流体波的穿透对地表电磁环境的影响

本文用两点边值问题的方法数值求解了磁流体波在穿透中纬度电离层和大气层的传播,给出了其对地表电磁环境的影响。在假设磁流体竖直入射,并且大地为理想导体的边界条件下,运用IMSL的子程序BVPFD计算给出了数值结果,数值结果显示磁流体波在穿透电离层和大气层的传播过程中,电场在低电离层和大气层逐渐衰减,在地面达到零,而磁场能够穿透电离层和大气层而到达地面,但在到达地面时衰减了一个量级。这对我们改善环境电磁辐射的监测,去除电磁监测过程中的本底干扰具有一定的启示参考作用。