Development and evaluation of RAMP I – a practitioner’s tool for screening of musculoskeletal disorder risk factors in manual handling

RAMP I is a screening tool developed to support practitioners in screening for work-related musculoskeletal disorder risk factors related to manual handling. RAMP I, which is part of the RAMP tool, is based on research-based studies combined with expert group judgments. More than 80 practitioners participated in the development of RAMP I. The tool consists of dichotomous assessment items grouped into seven categories. Acceptable reliability was found for a majority of the assessment items for 15 practitioners who were given 1?h of training. The usability evaluation points to RAMP I being usable for screening for musculoskeletal disorder risk factors, i.e., usable for assessing risks, being usable as a decision base, having clear results and that the time needed for an assessment is acceptable. It is concluded that RAMP I is a usable tool for practitioners.     

火灾高温下CFRP加固钢筋混凝土梁温度场分析

综合国外CFRP加固混凝土结构抗火试验相关研究,总结了CFRP的高温热工性能参数。用ANSYS软件对火灾高温下不同情况(无防火保护层和有防火保护层)和不同工况(防火涂料涂抹形式)下CFRP加固后的钢筋混凝土梁进行了温度场数值模拟研究。结果表明,防火涂料厚40 mm时,梁耐火极限可达2.5小时以上,且底面和两侧面全面涂抹防火涂料的防火效果最好。本文研究有助于进一步深入认识CFRP加固钢筋混凝土结构在高温下的力学性能和耐火极限,且对CFRP加固后的结构防火设计具有一定的指导意义。     

官地水电站竹子坝料场高边坡的稳定性分析及其影响因数研究

竹子坝料场是官地水电站混凝土浇筑骨料的重要来源之一。结合竹子坝料场的地形地质情况,以及料场开挖后形成的东、南、西三段人工边坡,运用刚体极限平衡的方法进行稳定性分析及其影响因数的研究。     

矿物材料吸附去除污水中磷的试验研究

采用粉煤灰、高岭土、泥渣(取电厂澄清池排泥作脱水干燥处理)作为吸附剂深度处理污水中的磷,对比分析了3种吸附剂的吸附速度、吸附性能及除磷效果。结果表明:粉煤灰和高岭土用时20 min完成对磷的有效吸附,沉降泥渣用时5 min即可实现同等吸附效果;沉降泥渣对污水中磷的吸附能力较好,投加量为0.2 g/L的泥渣对磷的去除率可达98.1%,而投加量为0.2 g/L粉煤灰或高岭土对磷的去除率仅达到77.2%。     

提升汇流环湿热环境适应性方法研究

目的提高汇流环在湿热环境下的适应能力。方法实物解剖,观察汇流环绝缘材料损坏情况、碳粉堆积情况,在不同温度、湿度下测试绝缘材料绝缘度、抗电强度,碳粉堆积和导电情况,比对不同绝缘材料性能,并找出最适合的绝缘材料,比对滚动汇流环、碳刷组件、刷丝组件,找到解决碳粉堆积的方法。结果汇流环受湿热影响会从接缝处和电缆连接处进入湿气,温度、湿度的上升会使得原绝缘材料性能下降,长时间使用汇流环,碳粉会在汇流环内堆积并受到湿热的影响而导电,局部密封汇流环可以减少湿气进入。PPO材料性能优异,可以替换原绝缘材料从而减少湿热的影响,使用刷丝组件替代碳刷可以避免碳粉的产生。结论综合运用局部密封、绝缘材料改进、碳刷组件改进三种措施,可以有效提高汇流环在湿热环境下的适应能力。     

Carbon Dioxide Balance of Wood Substitution: Comparing Concrete- and Wood-Framed Buildings

In this study a method is suggested to compare the net carbon dioxide (CO₂) emission from the construction of concrete- and wood-framed buildings. The method is then applied to two buildings in Sweden and Finland constructed with wood frames, compared with functionally equivalent buildings constructed with concrete frames. Carbon accounting includes: emissions due to fossil fuel use in the production of building materials; the replacement of fossil fuels by biomass residues from logging, wood processing, construction and demolition; carbon stock changes in forests and buildings; and cement process reactions. The results show that wood-framed construction requires less energy, and emits less CO₂ to the atmosphere, than concrete-framed construction. The lifecycle emission difference between the wood- and concrete-framed buildings ranges from 30 to 130 kg C per m² of floor area. Hence, a net reduction of CO₂ emission can be obtained by increasing the proportion of wood-based building materials, relative to concrete materials. The benefits would be greatest if the biomass residues resulting from the production of the wood building materials were fully used in energy supply systems. The carbon mitigation efficiency, expressed in terms of biomass used per unit of reduced carbon emission, is considerably better if the wood is used to replace concrete building material than if the wood is used directly as biofuel.     

纳米材料在水处理中的应用

纳米材料在水处理行业有着广阔的前景,文章主要介绍纳滤膜、光催化材料、纳米还原性材料及纳米吸附性材料在水处理中的应用现状及发展前景,并对纳米材料在水处理行业的应用提出了展望。     

改进型EGSB处理配置污水的小试研究

通过对不同上升流速下改进型EGSB和EGSB处理人工配置城市污水效果的比较研究,提出了一种更为有效的处理城市污水的反应器--改进型EGSB反应器,在上升流速为5.41m/h时,其出水的COD值稳定在60mg/L左右,出水SS明显要低于未改进的EGSB。同时还考察了运行期间改进型EGSB反应器内颗粒污泥的胞外多聚物、辅酶变化等,在高的上升流速下,改进型EGSB反应器中颗粒污泥的胞外多聚物含量和辅酶F420含量比未改进EGSB中的要高。     

我国大气腐蚀研究进展(续2)

总结了近几年来我国在大气腐蚀方面的研究现状和进展,尤其是国产、常用、量大、面广的 4大类材料在我国9类主要典型大气环境下的腐蚀数据积累;各类典型材料在典型环境下的大气腐蚀行为规律:大气环境因素对材料大气腐蚀的影响;碳钢、低合金钢大气腐蚀行为预测。特别是根据8 年试验结果总结出的大气腐蚀速度与试验时间之间具有幂函数关系的基础上,又进一步建立了腐蚀速度与合金元素之间的数学模型关系:探讨了采用ACM技术评估大气腐蚀严酷性;初步建立了大气腐蚀数据库．并正进一步采用计算机发展网络查询服务系统,实现科学数据共享;经20余年之研究,撰写了并出版中国材料自然环境腐蚀专著中大气腐蚀篇,还研制和生产了经济耐候钢。     

国内外军工材料环境试验现状及发展趋势

介绍军工材料环境试验对提高装备环境适应性的重要作用。从不同的技术方面,分析了国内外军工材料环境试验的现状、发展趋势以及主要差距。从规划的制定、新技术新方法的研发以及信息共享方面,提出设想。提出了目前需要研发新的环境试验、评价、管理方法和需要突破的关键技术。