Bacteria transport and deposition under unsaturated conditions: the role of the matrix grain size and the bacteria surface protein

Unsaturated (80% water saturated) packed column experiments were conducted to investigate the influence of grain size distribution and bacteria surface macromolecules on bacteria (Rhodococcus rhodochrous) transport and deposition mechanisms. Three sizes of silica sands were used in these transport experiments, and their median grain sizes were 607, 567, and 330 microm. The amount of retained bacteria increased with decreasing sand size, and most of the deposited bacteria were found adjacent to the column inlet. The deposition profiles were not consistent with predictions based on classical filtration theory. The experimental data could be accurately characterized using a mathematical model that accounted for first-order attachment, detachment, and time and depth-dependent straining processes. Visual observations of the bacteria deposition as well as mathematical modelling indicated that straining was the dominant mechanism of deposition in these sands (78-99.6% of the deposited bacteria), which may have been enhanced due to the tendency of this bacterium to form aggregates. An additional unsaturated experiment was conducted to better deduce the role of bacteria surface macromolecules on attachment and straining processes. In this case, the bacteria surface was treated using a proteolitic enzyme. This technique was assessed by examining the Fourier-transform infrared spectrum and hydrophobicity of untreated and enzyme treated cells. Both of these analytical procedures demonstrated that this enzymatic treatment removed the surface proteins and/or associated macromolecules. Transport and modelling studies conducted with the enzyme treated bacteria, revealed a decrease in attachment, but that straining was not significantly affected by this treatment.     

道路车辆电气及电子设备在振动试验中的应力循环和试验设计原则

本文试从振动试验的特点和受试样品承受振动激励的应力循环切入分析,为把握试验方案的拟订提供支持。同时也简要介绍了应力循环的计算方法,供试验人员参考使用。     

21世纪住区建设

面对世界发展趋势和中国建设高潮期,21世纪住宅建设需体现可持续发展,引入信息技术和新材料等高新技术,适应居住生活的发展。本文概述了当前世界发展趋势和国家住宅建设目标,住宅建设面临的科技问题,着重论述21世纪住区建设的规划设计原则。     

岳阳市城市绿化树种的选择及配置模式研究

选择观赏价值高、抗逆性强、保健功能强、经济效益高同时具有丰富历史文化底蕴和地方特色的植物材料用于城市林业建设中,可显著提高城市园林绿化的科技含量和综合效益;在园林植物配置上,根据园林美学原则和功能性要求,进行混植、群植、丛植、对植和孤植等,在充分发挥树木的群体美和个体美的同时可显著提高配置模式的整体功能性．     

海洋环境污染监测方案设计研究

海洋环境污染监测方案是一项复杂的系统工程。中国经过２０多年海洋环境污好监测的实践活动，积累了丰富的经验。但是，由于未能对海洋环境污染监测方案进行深入细致的研讨，致使今天我国海洋环境污染监测尚停留在定性或半定量描述阶段。该文第一次把有关海洋环境污染监测相结合，通过运用逻辑构思方法和监测方法学，详细分析监测方案设计中的各个阶段，监测目标的提出，到方案的实施；从监测数据的加工，到监测信息的发布都进行了辩证的分析。本文既是中国海洋环境污染监测方案的设计指南，也是中国海洋环境污染监测工作的集大成。     

乙二醇分批精馏塔的工艺设计

采用变参数操作法分批蒸馏回收乙二醇（EG）是对传统分批蒸馏法工艺技术的改进和创新,以新设计理念设计的精馏塔具有操作灵活、投资少、节能、适用性强等优点。新塔运行实践表明：与旧塔相比,其处理量大,可达6000 t/a;产品质量高,可达99.9%;乙二醇损耗低：12.5Kg/tEG;每年可多创产值102万元,经济效益显著。     

Place attachment and public acceptance of renewable energy: A tidal energy case study

Efforts by many governments to mitigate climate change by increasing deployment of renewable energy technologies have raised the importance of issues of public acceptance. The ‘NIMBY’ (Not In My Backyard) concept, although popular, has been critiqued as an appropriate and valid way to explain local opposition. This study applies an alternative approach, empirically investigating the role of place attachment and place-related symbolic meanings in explaining public responses to a tidal energy converter in Northern Ireland, said to be the first grid-connected device of its kind in the world. 271 residents in two nearby villages completed questionnaire surveys, three months post-installation, following up preliminary qualitative research using focus groups. Although results indicated predominantly positive and supportive responses to the project, manifest by emotional responses and levels of acceptance, significant differences between residents in each village were also observed. Contrasting patterns of association between place attachment and emotional responses suggest that the project enhanced rather than disrupted place attachments only in one of the two villages. In regression analyses, place attachment emerged as a significant, positive predictor of project acceptance in both places, affirming its value in explaining public response. Place-related symbolic meanings also emerged as significant, with contrasting sets of meanings proving significant in each context. Implications of the findings for research on place attachment and responses to land-use changes, as well as for developers seeking to engage with residents affected by energy projects are discussed.     

嘉陵江流域坡耕地“生态农业旅游”垂直景观模式

从治理水土流失角度出发，提出了坡耕地“生态农业旅游”技术与示范。其垂直生态景观模式按坡度和等高线布置：在坡度大于25°的山坡顶形成水保林木区，坡上15°～25°的陡坡种植桃树，坡中5°～15°的斜坡种植枇杷，坡下小于5°的缓坡地带种植特种水果、瓜类及蔬菜，坡底形成“稻—鱼”和“藕—鱼”特色水域区。道路系统设计为环山而下的水泥主路、观景石板干路、埂边地界小路三级，道路两侧实施还林还草。“农家乐”型旅游接待自然分布在试验区内，同时在坡上建立旅游“一条街”、坡底试验旅游产业化经营。果园内实施多熟作物覆盖、间种套种。垂直生态景观产生了独特而丰富的景观效果，并具有较好的生态功能、经济功能和社会功能。     

低能耗低成本排气消声器的研制

利用正交设计方法对汽车的排气消声器进行优化设计 ,弄清了不同参数对消声器性能的影响和变化规律。通过正交设计 ,使新消声器的各项指标得到提高。     

环境友好型城市环境指标体系研究

在提出环境友好性城市的基础上,阐述了环境友好型城市的基本内涵,提出了建设环境友好型城市环境指标体系的原则,并从环境保护与污染控制、环境经济社会协调度、环境生态建设与管理、环境伦理和意识方面选取了具体指标,构成了环境友好型城市完整的环境指标体系;同时对各评价指标因子的量化标准值的确定进行了分析研究,并提出了指标体系的计算方法和今后环境指标的研究方向.