浅谈重金属对污水处理中活性污泥影响

综述了污水处理中重金属对生物反应动力学常数,活性污泥微生物群落结构及污水生物处理效率的影响,进而研究了重金属对生物脱氮除磷的毒性效应,对提高污水处理效果具有重要的现实意义。     

In vitro digestion and DGT techniques for estimating cadmium and lead bioavailability in contaminated soils: influence of gastric juice pH

A sensitivity analysis was conducted on an in vitro gastrointestinal digestion test (i) to investigate the influence of a low variation of gastric juice pH on the bioaccessibility of Cd and Pb in smelter-contaminated soils (F_B, using the unified bioaccessibility method UBM) and fractions of metals that may be transported across the intestinal epithelium (F_A, using the diffusive gradient in thin film technique), and (ii) to provide a better understanding of the significance of pH in health risk assessment through ingestion of soil by children. The risk of metal exposure to children (hazard quotient, HQ) was determined for conditions that represent a worst-case scenario (i.e., ingestion rate of 200 mg day^− 1) using three separate calculations of metal daily intake: estimated daily intake (EDI), bioaccessible EDI (EDI-F_B), and oral bioavailable EDI (EDI-F_A). The increasing pH from 1.2 to 1.7 resulted in: (i) no significant variation in Cd-F_B in the gastric phase but a decrease in the gastrointestinal phase; (ii) a decrease in soluble Pb in the gastric phase and a significant variation in Pb-F_B in the gastrointestinal phase; (iii) a significant decrease in Cd-F_A and no variation in Pb-F_A; (iv) no change in EDI-F_B and EDI-F_A HQs for Cd; (v) a significant decrease in EDI-F_B HQs and no significant variation in EDI-F_A HQ for Pb. In the analytical conditions, these results show that risk to children decreases when the bioavailability of Pb in soils is taken into account and that the studied pH values do not affect the EDI-F_A HQs. The present results provide evidence that the inclusion of bioavailability analysis during health risk assessment could provide a more realistic estimate of Cd and Pb exposure, and opens a wide field of practical research on this topic (e.g., in contaminated site management).     

Investigation of different approaches to reduce allergens in asthmatic children's homes--the Breath of Fresh Air Project, Cornwall, United Kingdom

During 2001 to 2004, a study was conducted to assess the indoor environmental and health impact of installing allergen-reducing interventions in the homes of asthmatic children. Based on the results of a pilot study, to determine an intervention that would provide improved symptom scores and a reduction in house dust mite allergen (Der p 1), mechanical ventilation and heat recovery (MVHR) systems were installed in 16 homes. Environmental and respiratory health assessments were conducted before and after the installation of the MVHR systems. The results indicated that the installation of MVHR systems reduced Der p 1 concentrations in living room carpets and mattresses. There were significant reductions in symptom scores for breathlessness during exercise, wheezing, and coughing during the day and night. Although, there was not a parallel control group for the main study, the lack of change in the pilot study control group (who did not receive an intervention), indicated that the changes in symptom scores were in part to do with the intervention. Larger scale trials are needed to determine the efficacy of MVHR systems in homes to improve indoor air quality and reduce asthma symptoms.     

Optimization of bridge maintenance strategies based on structural health monitoring information

Highway bridges are subjected to strength degradation processes. Under budget constraints, it is important to determine the best maintenance strategies. Optimized strategies, based on prediction models, are already considered for the maintenance and operation of highway bridges. Prediction models are updated both in space and time by using non-destructive testing methods. Nevertheless, there is an urgent need for the efficient inclusion of structural health monitoring (SHM) data in structural assessment and prediction models. Indeed, SHM allows keeping strength degradation processes under control and should be included in life-cycle cost models. The lifetime reliability of structures is characterized by survivor functions. The SHM data enable to update the probability density function of time to failure through a Bayesian process. The aim of this paper is threefold: (a) to include SHM data in a bridge life-cycle cost analysis, (b) to determine optimal maintenance strategies based on monitoring information, and (c) to show the benefits of SHM. Optimal strategies are determined considering the cases without and with including monitoring results; the benefit of monitoring is then highlighted. The proposed concepts are applied to the I-39 Northbound Bridge over the Wisconsin River in Wisconsin, USA. A monitoring program of that bridge was performed by the ATLSS Engineering Research Center at Lehigh University.     

基于规范及实测风谱的苏通大桥抖振响应对比研究

复核结构设计是桥梁结构健康监测系统的主要功能之一。以世界第一大跨斜拉桥——苏通大桥为工程背景,采用实测风谱对大桥设计阶段基于规范谱所进行的抖振分析进行验证。首先采用非线性最小二乘法对桥址区实测强风紊流功率谱密度函数进行拟合,获得实测谱曲线,并分别以该实测拟合谱和规范谱为目标谱分别模拟桥址区三维脉动风场。然后采用上述两种风场,基于ANSYS对苏通大桥进行非线性时域抖振响应分析。两种分析结果的对比表明:与实测谱相比,基于规范谱所得的主梁抖振响应情况不一,但主塔抖振响应均偏于保守;两种抖振响应的PSD曲线整体趋势基本一致。分析结果可为该桥的风致抖振性能评价提供研究信息,同时对其他类型结构的抗风设计具有重要的参考价值。     

小型天然气液化厂的安全生产运行管理

阐述了天然气液化厂中,安全生产、持续运行、员工成长3方面的运行管理实践。     

现代室内绿色设计新视角

分析了现代家居绿色设计中存在的误区,在提出绿色设计思想的基础上阐述了绿色建材在室内设计中的运用,探讨了如何利用色彩、植物配置、照明来点缀室内环境,以期更好的满足现阶段人们的生活和精神需要。     

江西省卫生服务能力建设工程对乡镇卫生院服务功能开展的影响

目的探讨江西省卫生服务能力建设工程对乡镇卫生院服务功能的影响,为今后健全和完善乡镇卫生院的服务功能提供依据。方法对2010年1 552所乡镇卫生院采用江西省乡镇卫生院卫生服务能力建设工程终期调查表进行调查。用描述性统计指标对2010年乡镇卫生院工作开展及科室设置情况进行分析,并与2007年的数据进行比较。结果 2010年传染病疫情监测开展率为96.08%、常规免疫接种开展率为94.13%较2007年略有降低（97.19%、95.55%）,绝对增加量分别为-1.11%、-1.42%;杀虫、灭鼠开展率为74.48%、碘缺乏病监督监测开展率为69.13%较2007年明显增加（71.27%、64.73%）,绝对增加量分别为3.21%、4.40%。2010年健康教育开展率为96.67%、儿童健康检查开展率为94.78%较2007年明显增加（94.04%、90.05%）,绝对增加量分别为2.63%、4.73%。但2010年儿童生长监测、体弱儿管理的开展情况不理想（74.48%、69.13%）。2010年内科开展率为100.00%、儿科开展率为100.00%、药房（含中药）开展率为100.00%、妇产科开展率为94.99%、化验室开展率为93.66%、B超开展率为92.95%、发热门诊开展率为92.89%、肠道门诊开展率为90.47%、心电图室开展率为87.47%较2007年明显增加（99.73%、92.21%、98.39%、87.96%、90.84%、82.66%、86.32%、90.45%、80.32%）,且均有明显改善。2010年剖腹产开展率为40.60%、胃切除开展率16.06%为较2007年明显降低（46.20%、21.60%）,绝对增加量分别为-5.60%、-4.64%,且外科手术的开展总体呈下降趋势。2010年血、尿、便三大常规开展率为92.75%、乙肝表面抗原开展率为85.18%、乙肝二对半开展率为82.31%较2007年明显增加（90.25%、79.91%、77.49%）,绝对增加量分别为2.50%、5.27%、4.82%,且整体有上升的趋势。2010年胃肠钡餐造影（18.73%）较2007年（22.19%）明显降低。结论江西省乡镇卫生院服务功能整体工作的开展有显著的改善,基本达到预期的目标,但还存在不足及需改善。     

基于多主体协作技术的光纤Bragg光栅传感器网络自修复实现

针对光纤布拉格光栅(FBG)传感器监测飞机机翼盒段试验件上的静态载荷,对多主体协作技术实现结构健康监测中光纤Bragg光栅传感器网络的自修复性进行研究。当某个主体的光纤Bragg光栅传感器发生故障时,首先,传感主体依据采集到的传感器信号利用支持向量回归机算法对外部载荷位置进行预测,然后系统协作主体对两个主体的预测结果进行协作,共同对故障传感器信号进行修复,最终获得损伤位置的识别结果。研究表明:多主体协作之后的损伤位置平均识别精度比单独采用任何一个主体的平均识别精度都高,可以对失效传感器信号进行一定的补偿、修复。     

移动医疗商业介入路径研究

首先,分析移动医疗发展的现状,指出中国移动医疗行业面临巨大的机遇.其次,对比分析传统医疗行业产业链和移动医疗产业链,指出移动医疗具有良好的行业发展前景.然后,具体分析移动医疗的三大类群用户和产业链,指出可产生增值效益的商业模式对移动医疗行业至关重要.最后,通过对国外成熟的移动医疗商业模式的分析,提出中国可发展的未来移动医疗商业模式.