抽出式通风煤巷掘进过程中粉尘浓度分布规律的数值模拟

根据气固两相流理论，针对矿井掘进工作面的特点，采用计算流体力学的离散相模型（DPM）对掘进工作面通风过程中粉尘浓度进行数值模拟，总结抽出式通风掘进巷道中粉尘浓度的沿程分布及变化规律。     

城市可降解生活垃圾的生物综合处理模式初探

针对现有城市生活垃圾处理方式的不足,结合垃圾生物处理特点,设计了集混合菌群降解、生物过滤除臭、污水回用及植被绿化于一体的立体处理体系。结果表明,该系统在城市生活垃圾的“三化”处理中具有显著的潜势:既使生活垃圾在食物链外形成安全的闭路循环,防止有害物质向人居环境入渗;同时,处理设施的立体化、终产物的生物转化以及即刻的市场效应,有效地增强了系统的消纳能力,缓解了传统处理方式对城市空间的压力。该系统对我国中小城市生活垃圾的综合利用具有积极的参考价值。     

一种DSP+FPGA实时信号处理系统

简要叙述了常用的信号处理系统的类型与处理机结构,介绍了正逐步得到广泛应用的DSP+FPGA处理机结构,在此基础上提出了一种实时信号处理的线性流水阵列,并举例说明了该结构的具体实现,最后分析说明了此结构的优越性。     

山东省城市生活垃圾管理现状及对策

随着经济的发展,城市生活垃圾逐渐成为山东省面临的重大问题.系统分析了山东省城市生活垃圾的收运及处理现状,并对其对策进行了讨论,认为山东省应立足现实,完善城市生活垃圾管理体系;对城市生活垃圾分类收集,以源头控制为主,并逐步改进现有的较为单一的卫生填埋技术;尝试应用多种先进的综合处理新技术,改变传统的思维模式,加快城市生活垃圾处理市场化、产业化的步伐,走可持续发展之道路.     

Enzyme-Retted Flax Fiber and Recycled Polyethylene Composites

Municipal solid wastes generated each year contain potentially useful and recyclable materials for composites. Simultaneously, interest is high for the use of natural fibers, such as flax (Linum usitatissimum L.), in composites thus providing cost and environmental benefits. To investigate the utility of these materials, composites containing flax fibers with recycled high density polyethylene (HDPE) were created and compared with similar products made with wood pulp, glass, and carbon fibers. Flax was either enzyme- or dew-retted to observe composite property differences between diverse levels of enzyme formulations and retting techniques. Coupling agents would strengthen binding between fibers and HDPE but in this study fibers were not modified in anyway to observe mechanical property differences between natural fiber composites. Composites with flax fibers from various retting methods, i.e., dew- vs. enzyme-retting, behaved differently; dew-retted fiber composites resulted in both lower strength and percent elongation. The lowest level of enzyme-retting and the most economical process produces composites that do not appear to differ from the highest level of enzyme-retting. Flax fibers improved the modulus of elasticity over wood pulp and HDPE alone and were less dense than glass or carbon fiber composites. Likely, differences in surface properties of the various flax fibers, while poorly defined and requiring further research, caused various interactions with the resin that influenced composite properties.     

南充市空气中可吸入颗粒物污染水平分析

本文在连续1年又5个月同步采样的基础上，测得南充市市辖三城区5个采样监测点环境空气中PM10的浓度及其时空变化进行了分析。结果表明，PM10的日平均浓度范围为0．020～1．030mg／m^3，超标率达38．0％；周日均浓度在0.040～0．520mg／m^3之间，超标率达到了37．8％。空气污染最重为嘉陵城区，其次为高坪城区，再次为石油学院、炼油厂和市府二院。浓度季节变化特征表现为冬季最高，其次为秋季，再次为春季，最轻为夏季。     

Effects of planned expansion of waste incineration in the Swedish district heating systems

Recent targets for reduced amounts of waste to landfills in Sweden will result in a large increase in waste incineration with recovery of energy, used primarily for district heating. The aim of this study is to investigate what changes in the usage of other fuels and technologies for district heat production would be caused by this increase. A questionnaire was sent out to the largest district heating companies, and simulations in an energy systems model were carried out. The analysis shows that increased waste incineration reduces the demand for other fuels, especially biomass, for district heat production. The effects include reductions in operating hours as well as the avoidance or postponement of investments in new plants for district heat production. Increased waste incineration will also lead to a greater use of district heating in Sweden.     

垃圾填埋场有机污染物的生物降解机理

概述了垃圾填埋场中微生物的作用特性，微生物对有机污染物的降解及其影响因素，介绍了有机污染物降解的两种生化动力学模型：“速度指数模型”和“双曲线速度模型”，以及垃圾降解的动力学方程。     

垃圾焚烧飞灰中重金属的固化/稳定化处理实验研究

研究了城市生活垃圾焚烧-电灰的特性及飞灰中重金属的特性,对利用水泥作粘结剂进行飞灰固化/稳定化处理效果开展了系统的实验研究,分析了水泥固化/稳定化飞灰的工艺特点和最佳工艺参数,并讨论了粘结剂固化飞灰机理以及重金属浸出毒性,为进一步研究城市生活垃圾焚烧飞灰的无害化处理与利用提供了有重要价值的参考依据.     

Effect of 450 MHz Microwave Modulated with 217 Hz on Human EEG in Rest

Summary This study focuses on discrimination of changes, produced by low-level microwave exposure in intensity and time variability of the human EEG at rest. The power spectral density (PSD) method and nonlinear scaling analysis of the length distribution of low variability periods (LDLVP) were selected for analysis of the EEG signal. During the study, 19 healthy volunteers were exposed to a microwave (450 MHz) of 217 Hz frequency on-off modulation. The field power density at the scalp was 0.16 mW/cm². The experimental protocol consisted of ten cycles of repetitive microwave exposure. Signals from frontal, temporal, parietal and occipital EEG channels on EEG theta, alpha and beta rhythms were analysed. Exposure to microwave causes average increase of EEG activity. LDLVP analysis discriminated significant effect in time variability for 2 subjects (11%). PSD method detected significant changes in intensity for 4 subjects (21%). The effect of low-level microwave exposure is stronger on EEG beta rhythm in temporal and parietal regions of the human brain.