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221.
Some strategic raw materials do have an extremely unsecure supply situation. Several working groups around the world have made criticality assessments for metallic raw materials to analyze the driving impact factors for this instability. However, the influences on raw material availability are manifold and therefore criticality assessment methods are very heterogeneous. Here we give an overview about the differences and similarities of supply risk evaluation in 15 criticality assessment methods. We take the example of Indium, which has been rated in 60% of these criticality studies, and show which data base is used for supply risk evaluation. Our results show a lack of consensus about which indicators give reliable information for raw material supply risk and how these indicators should be aggregated. We anticipate our essay to be a starting point for more justified indicator selection and weighting in criticality assessments.  相似文献   
222.
针对酸性污染土物理力学性质恶化的现象,采用室内人工模拟受酸液污染土样的方法,开展土常规试验、压缩试验探究Q2黄土在酸液浸泡时间和酸液浓度双因素作用下,试样孔隙比、含水率等基本物理及压缩系数、压缩模量等指标和压缩e—p曲线的变化规律,以及水-酸耦合作用对黄土压缩性的影响规律。结果表明:浸泡时间一定时,随酸液浓度增大,含水率、孔隙比、压缩系数在逐渐增大,压缩模量在减小。浸泡12 d时,酸液浓度0.1 mol/L增加至3 mol/L,压缩系数a1-2由0.355 MPa-1增大到1.275 MPa-1,压缩模量Es1-2由5.580 MPa减小至1.855 MPa;酸液浓度一定时,随浸泡时间延长,含水率、孔隙比、压缩系数在逐渐增大,压缩模量在减小。酸液浓度3 mol/L时,浸泡时间从1 d至12 d,压缩系数a1-2由0.308 MPa-1增大到1.275 MPa-1,压缩模量Es1-2由6.301 MPa减小至1.855MPa;水-酸耦合作用提高了黄土压缩性,且在充分浸泡条件下,酸液对黄土压缩性的影响远大于水的影响。研究结果可为酸蚀黄土区工程建设提供相关参考。  相似文献   
223.
孙世梅  马坤  傅贵 《安全》2019,40(9):64-68,6
为了进一步了解城市地下空间管道施工坍塌事故发生的原因,笔者运用行为安全"2-4"模型事故致因分析方法分析了27起典型的管道施工坍塌事故,分析得出17类共109个不安全动作和6类共34个不安全物态,不安全动作中发生率较高的是不按要求对基坑放坡和加固、未对作业人员安全教育培训或者培训不到位以及施工前未进行风险识别或者识别不到位,并对这3方面不安全动作进行进一步分析;不安全物态中发生率较高的是未加支撑的基坑侧壁、存在淤泥和松软土质结构的开挖层。得出安全知识不足7类共58项,安全意识的淡薄,对于生产主管主要体现在雇佣临时工,施工现场作业人员则体现在不注意环境周围存在的安全隐患;得出安全管理体系的欠缺9类共88项,因安全生产规章制度缺乏或制度不合格导致安全管理体系欠缺占比最大,因无安全技术交底或技术交底不到位导致安全管理体系的欠缺居于第二位,施工前未进行风险识别或者识别不到位在27起事故中也出现12次,也是安全管理工作中不可忽视的因素。  相似文献   
224.
Objectives: The objective of this study was to assess and compare the current lateral impact biofidelity of the shoulder, thorax, abdomen, and pelvis of the Q6, Q6s, and Hybrid III (HIII) 6-year-old anthropomorphic test devices (ATDs) through lateral impact testing.

Methods: A series of lateral impact pendulum tests, vertical drop tests, and Wayne State University (WSU) sled tests was performed, based on the procedures detailed in ISO/TR 9790 (1999) and scaling to the 6-year-old using Irwin et al. (2002 Irwin AL, Mertz HJ, Elhagediab AM, Moss S. Guidelines for assessing the biofidelity of side impact dummies of various sizes and ages. Stapp Car Crash J. 2002;46:297319.[PubMed] [Google Scholar]). The HIII used in this study was tested with the Ford-designed abdomen described in Rouhana (2006 Rouhana SW. Abdominal impact injury research—a review. J Biomech. 2006;39(Suppl 1):S157–S158. [Google Scholar]) and Elhagediab et al. (2006 Elhagediab AM, Hardy WN, Rouhana SW. Advancements in the rate-sensitive abdomen for the Hybrid III family of dummies. J Biomech. 2006;39(Suppl 1):S158.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]). The data collected from the 3 different ATDs were filtered using SAE J211 (SAE International 2003 SAE International. Surface Vehicle Recommended Practice. Instrumentation for Impact Test—Part 1—Electronic Instrumentation. Warrendale, PA: SAE International; 2003. SAE Standard J211-1. [Google Scholar]), aligned using the methodology described by Donnelly and Moorhouse (2012 Donnelly BR, Moorhouse K. Optimized phasing of PMHS response curves for biofidelity targets. Paper presented at: IRCOBI Conference; 2012. [Google Scholar]), and compared for each body region tested (shoulder, thorax, abdomen, and pelvis). The biofidelity performance in lateral impact for the 3 ATDs was assessed against the scaled biofidelity targets published in Irwin et al. (2002 Irwin AL, Mertz HJ, Elhagediab AM, Moss S. Guidelines for assessing the biofidelity of side impact dummies of various sizes and ages. Stapp Car Crash J. 2002;46:297319.[PubMed] [Google Scholar]), the abdominal biofidelity target suggested in van Ratingen et al. (1997 van Ratingen M, Twisk D, Schrooten M, Beusenberg M. Biomechanically based design and performance targets for a 3-year-old child crash dummy for frontal and side impact. Paper presented at: 41st Stapp Car Crash Conference; 1997. [Google Scholar]), and the biofidelity targets published in Rhule et al. (2013 Rhule H, Donnelly B, Moorhouse K, Kang YS. A methodology for generating objective targets for quantitatively assessing the biofidelity of crash test dummies. Paper presented at: 23rd Enhanced Safety of Vehicles Conference; 2013. [Google Scholar]). Regional and overall biofidelity rankings for each of the 3 ATDs were performed using both the ISO 9790 biofidelity rating system (ISO/TR 9790 1999) and the NHTSA's external biofidelity ranking system (BRS; Rhule et al. 2013 Rhule H, Donnelly B, Moorhouse K, Kang YS. A methodology for generating objective targets for quantitatively assessing the biofidelity of crash test dummies. Paper presented at: 23rd Enhanced Safety of Vehicles Conference; 2013. [Google Scholar]).

Results: All 3 6-year-old ATD's pelvises were rated as least biofidelic of the 4 body regions tested, based on both the ISO and BRS biofidelity rating systems, followed by the shoulder and abdomen, respectively. The thorax of all 3 ATDs was rated as the most biofidelic body region using the aforementioned biofidelity rating systems. The HIII 6-year-old ATD was rated last in overall biofidelity of the 3 tested ATDs, based on both rating systems. The Q6s ATD was rated as having the best overall biofidelity using both rating systems.

Conclusions: All 3 ATDs are more biofidelic in the thorax and abdomen than the shoulder and pelvis, with the pelvis being the least biofidelic of all 4 tested body regions. None of the 3 tested 6-year-old ATDs had an overall ranking of 2.0 or less, based on the BRS ranking. Therefore, it is expected that none of the 3 ATDs would mechanically respond like a postmortem human subject (PMHS) in a lateral impact crash test based on this ranking system. With respect to the ISO biofidelity rating, the HIII dummy would be considered unsuitable and the Q-series dummies would be considered marginal for assessing side impact occupant protection.  相似文献   
225.
Q4 Safety在海洋石油安全管理中的应用   总被引:1,自引:0,他引:1  
简要介绍了安全生产管理软件Q4 Safety在曹妃甸油田的应用背景;着重从危险辨识和风险评估、隔离的管理和控制、工作许可的管理和控制、测试单的管理和控制以及相关负责人五个方面,结合工作流程,对该软件在海上油田的应用情况进行了介绍和分析,并提出了建议.  相似文献   
226.
生活与工业污水混合处理系统中关键毒物追踪   总被引:8,自引:0,他引:8  
以常州市城北污水处理厂的进水和A^2O出水为研究对象,采用毒性鉴别评价(T IE)程序,对关键毒物进行了追踪。结果表明,进水对大型蚤(Daphnia magna)具 有24h急性毒性,经过A^2O系统的处理,出水已不显示24h急性毒性;因曝气可去除废水毒性,C18固相提取亦可去除废水毒性,据此判断进水中存在的主要毒物 为挥发性非极性有机化合物。进出水的GC/MS图谱显示,处理前后有机物浓度大大降低,关键毒物基本去除。  相似文献   
227.
采用静态暗箱一二氧化碳红外分析仪法研究了重庆丘陵山区石灰性黄壤土壤呼吸特征及影响因素.结果表明,土壤呼吸速率呈现季节性动态变化特征,冬季较低,夏季较高,与地温的季节动态变化基本一致;土壤呼吸与地温之间呈指数关系,其中与5 cm地温的相关性最好;不同土层、不同处理的Q10值不同,变化范围为1.67~2.69.不同田间管理措施对土壤呼吸速率有明显影响,表现为施肥土壤>未施肥处理,种植作物土壤>裸地;化肥使种植作物土壤的年平均呼吸速率增加70.8%,化肥、粪肥共同作用增加129%;与裸地相比,单种作物不施肥不能显著增加土壤CO2排放.裸地春、秋、冬季的土壤呼吸速率与土壤水分呈直线关系,决定系数R2=0.414,P<0.01.在夏季,种植作物未施肥和施化肥处理两者也呈直线关系,R2分别为0.5361和0.4261(P<0.05),其他季节两者未表现出明显的规律性.  相似文献   
228.
2012年2月采集闽江河口鳝鱼滩短叶茳芏(Cyperus malaccensis),芦苇(Phragmites australis)和互花米草(Scirpus alterniflora) 3个典型潮汐沼泽植被带0~30cm(间隔5cm)土壤样品,在不同温度(10,20和30℃)进行15d室内厌氧培养实验,探讨河口区不同沼泽植被带土壤甲烷产生潜力及其温度敏感性(Q10值)的特征.结果表明,指数模型较好地拟合不同沼泽植被带土壤甲烷产生与温度的相关关系;温度由10℃升至20℃时,3个沼泽植被带土壤甲烷产生潜力Q10值的均值分别为5.04,14.92和14.81,最大值均在培养期间的第13~15d分别出现于10~15cm,15~20cm和20~25cm三个土层;温度由20℃升至30℃时,3个沼泽植被带土壤甲烷产生潜力Q10值的均值分别为3.56,4.99和3.43,最大值分别在培养期间的第4~6d,第4~6d和第7~9d出现于0~5cm,0~5cm和15~20cm三个土层;植被类型和土壤深度对甲烷产生潜力及Q10值均具有显著的影响(P<0.05).  相似文献   
229.
2种杀虫剂对日本沼虾的急性毒性   总被引:1,自引:0,他引:1  
研究了毒死蜱和硫丹对日本沼虾(Macrobrachium nipponense)的毒性作用.根据预试验确定2种杀虫剂对日本沼虾的急性毒性试验浓度,测定沼虾24和48 h的半致死浓度p(LC50),在0~48 h的ρ(LC50)值范围内设定6个浓度梯度,对日本沼虾进行24 h胁迫试验以测定耗氧量和排氨量.毒死蜱和硫丹对日本沼虾的24和48 hρ(LC50)分别为5.03、2.01和8.47、4.02 μg·L-1,其安全质量浓度分别为0.096和0.272 μg·L-1,表明日本沼虾对毒死蜱的敏感性明显高于硫丹.随着2种杀虫剂浓度的逐渐升高,日本沼虾的耗氧量和排氨量均呈现下降趋势,表明日本沼虾采用相同的适应方式来抵御2种杀虫剂对其基础代谢的胁迫,表现为被动的忍耐.  相似文献   
230.
We estimate the value of information (VOI) for three key parameters of climate integrated assessment models (IAMs): marginal damages at low temperature anomalies, marginal damages at high temperature anomalies, and equilibrium climate sensitivity. Most empirical studies of climate damages have examined temperature anomalies up to 3 °C, while some recent theoretical studies emphasize the risks of “climate catastrophes,” which depend on climate sensitivity and on marginal damages at higher temperature anomalies. We use a new IAM to estimate the VOI for each parameter over a range of assumed levels of study precision based on prior probability distributions calibrated using results from previous studies. We measure the VOI as the maximum fixed fraction of consumption that a social planner would be willing to pay to conduct a new study before setting a carbon tax. Our central results suggest that the VOI is greatest for marginal damages at high temperature anomalies.  相似文献   
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