浅谈爆破振动的控制措施

结合爆破振动的作用机理,分别对减少振源爆炸能量、干扰降振、阻断振动波传播途径、控制爆破规模、合理选择分段间隔时间等爆破振动主要控制措施进行了分析讨论。并根据实际施工情况分析了通过电子雷管实现干扰降振的减振效果,为类似工程提供借鉴作用。     

Fruit Stones from Industrial Waste for the Removal of Lead Ions from Polluted Water

Lead, one of the earliest metals recognized and used by humans, has a long history of beneficial use. However, it is now recognized as toxic and as posing a widespread threat to humans and wildlife. Treatment of lead from polluted water and wastewater has received a great deal of attention. Adsorption is one of the most common technologies for the treatment of lead-polluted water. This technique was evaluated here, with the goal of identifying innovative, low-cost adsorbent. This study presents experiments undertaken to determine the suitable conditions for the use of peach and apricot stones, produced from food industries as solid waste, as adsorbents for the removal of lead from aqueous solution. Chemical stability of adsorbents, effect of pH, adsorbents dose, adsorption time and equilibrium concentration were studied. The results reveal that adsorption of lead ions onto peach stone was stronger than onto apricot stone up to 3.36% at 3 h adsorption time. Suitable equilibrium time for the adsorption was 3–5 h (% Pb adsorption 93% for apricot and 97.64% for peach). The effective adsorption range for pH in the range was 7–8. Application of Langmuir and Freundlich isotherm models show high adsorption maximum and binding energies for using these adsorbents for the removal of lead ions from contaminated water and wastewater.     

Are older drivers’ driving patterns during an on-road driving task representative of their real-world driving patterns?

Abstract

Objective: The current study investigated whether older drivers’ driving patterns during a customized on-road driving task were representative of their real-world driving patterns.

Methods: Two hundred and eight participants (male: 68.80%; mean age?=?81.52 years, SD?=?3.37 years, range?=?76.00–96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants’ real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant’s vehicle.

Results: During the 4-month period prior to completing the on-road driving task, participants’ median real-world driving trip distance was 2.66?km (interquartile range [IQR]?=?1.14–5.79?km) and their median on-road driving task trip distance was 4.41?km (IQR?=?2.83–6.35?km). Most participants’ on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n?=?198).

Conclusions: These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants’ real-world driving patterns.     

填埋场不同深度垃圾土压缩性的室内试验研究

阐述了垃圾土的压缩机理,归纳了国内外垃圾土压缩性指标的研究成果。根据某填埋场3个不同深度的垃圾土试样,在改装后的高压固结仪上进行压缩试验,得到垃圾土的压缩系数a、主压缩指数C、修正主压缩指数C'、压缩模量E以及体积压缩系数m,并对试验结果进行分析。试验结果表明,垃圾土的初始孔隙比随填埋深度的增加而减小,垃圾土的压缩指数随其可降解度和有机质含量的减少而降低,垃圾土具有高压缩性,其压缩性指标与垃圾的组成和填埋深度有关。将得到的压缩性指标与国内外的资料进行了比较,可为填埋场的设计及变形计算提供参考。     

丁酸胁迫对产氢污泥以厨余为底物的产氢影响

采用丁酸对产氢污泥进行胁迫处理,经胁迫后的污泥接种厨余垃圾进行产氢实验,考察丁酸胁迫对提高产氢性能的影响。结果表明,低浓度胁迫能提高产氢污泥的耐丁酸性,从而提高产氢量,而胁迫浓度过高则抑制产氢污泥活性,胁迫浓度呈"horm esis"效应。实验采用的4 g/L胁迫浓度为最佳,反应结束后,丁酸浓度和产氢量分别为8 417.1 mg/L和63.72 mL/g VS,比空白提高了31.3%和114%。产氢过程中SCOD的主要来源是有机酸。对产氢污泥胞外多聚物(EPS)的测定表明,厨余垃圾酸化速率、氢气产生速率和EPS总量成正相关。     

医疗废物焚烧处理核心技术的开发及应用

国内已建成的医疗废物焚烧设施目前普遍存在进料系统不稳定、玻璃结渣和高浓度HCl气体的排放的问题。这些技术难点已成为医疗废物焚烧处置行业发展的瓶颈。本文介绍了可解决上述问题的"可调节医疗废物恒流量进料技术"、"医废焚烧防玻璃结渣技术"和"含高浓度氯化氢医废尾气处理技术"三项医疗废物焚烧处理核心技术的主要特点及技术指标与应用实例。     

衡水市医疗废物处理现状调查及对策

医疗废物是一类成分复杂并有特殊危害的危险废弃物。通过分析衡水市医疗废物处理过程中存在的分散处置、处理率低等问题,提出了加强管理监督机制、提高医疗废物收集处理率的应对策略。通过综合比较分析几种医疗废物处理方法的优缺点,指出高温焚烧法集中处置是衡水市医疗废物的最佳处理方法。     

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。     

Olive oil mill wastewater for soil nitrogen and carbon conservation

In this work the application of two levels of N fertilizer (NH₄NO₃) dissolved in water or olive oil mill wastewater (OOMW) diluted 10 or 20 times in water, has been studied in relation to the properties of two soils (Loam and Silt-Clay-Loam). Also, the effect of irrigation water bubbled with CO₂ (Dissolved Inorganic Carbon, DIC) was studied. Nitrate N, ammonium N, total N, organic C (OC), and CaCO₃ contents were determined in the soil as well as pH, electrical conductivity (EC), oxidation–reduction potential (ORP), and absorbance at 250 and 360 nm.     

航空环境与机载设备环境试验规范的制定

本文简要介绍了航空环境中对流层、平流层、电离层、外大气层的基本环境及民用飞机机型的基本情况,对机载设备环境试验标准的选用及标准中提供的机载设备环境试验项目和应力等级的剪裁,归纳整理出了应考虑的因素：飞机舱内、舱外,飞机类型、飞机性能,并对每个试验项目的目的做了简要介绍。