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731.
以太湖淤泥和自来水厂污泥为原料进行烧结砖的制备研究,干原料经混合加湿搅拌,制成4 cm×4cm×4cm的砖体试样,干燥后放入马弗炉中焙烧;测试了砖坯的含水率、干燥收缩,烧结砖的烧失量、烧成收缩、表观密度、吸水率和抗压强度,并利用XRD和SEM分别测试了烧结砖的矿物成分,和微观形貌特征。研究结果表明,减少淤泥含量导致砖的密度和抗压强度降低,烧失量、烧成收缩率和吸水率上升;淤泥掺量减少到60%,成型含水率为23%,经950℃高温煅烧后,所得砖体质量较好,强度满足MU10等级。  相似文献   
732.
通过对法库县环境噪声质量状况及污染原因的分析,提出了控制噪声污染的对策,以期进一步改善法库县环境质量.  相似文献   
733.
目的针对目前根据天气预报进行防台避台的决策缺乏定量模型,定性根据天气预报结果进行防、避台风往往会造成巨大的不必要的浪费的现象,为科学合理地利用天气预报进行防、避台风提供有效工具。方法对防避费用和损失费用进行比较评估。结果给出了舰船防避热带气旋费效比优化决策模型,并进行了数据分析。结论防避热带气旋应该考虑天气不确定性因素。  相似文献   
734.
针对注水站泵房的噪声源及产生原因进行分析,就机械、电磁等噪声源,采取设备改造、隔声、消声、吸声等噪声控制措施,实施效果较好。  相似文献   
735.
针对如何做好工业企业厂界噪声监测质量保证工作问题,文中介绍了如何做好监测前的质量保证工作,包括监测人员的保证作用、监测方法的保证作用、噪声监测仪的保证作用、噪声校准仪的保证作用,探讨了对现场监测质量测定的影响因素,主要包括对气象要求、测量工况、监测情况调查、测点位置、测量时间、背景噪声值扣除、人为噪声的排除和测量记录对监测质量的影响,并对监测数据进行了处理及分析,这有益于做好工业企业厂界噪声监测质量保证工作。  相似文献   
736.
INTRODUCTION: The urban road traffic accident (RTA) risks for the city of Zagreb, Croatia, from 1999 through 2000 were analyzed with the aim of reducing the increasing injury incidence. METHOD: Simple and bivariate analysis using chi(2), odds ratio, and confidence interval of 95% was used to determine risks in three outcome groups: killed, severely, and mildly injured. RESULTS: There were 528 RTA victims consisting of 260 severely, 213 mildly injured, and 55 killed at the scene of an accident and during transportation. More fatal accidents occurred during night hours (OR=3.78; 95% CI, 2.08-6.85), on urban road links (OR=2.33; 95% CI, 1.30-4.19), and at exceeding speed limit (OR=2.56; 95% CI, 1.43-4.61). More people were injured than killed on urban junctions (OR=5.27; 95% CI, 2.21-12.57). The highest combined risk of dying or being severely injured was found in males, driving at excessive speed, on urban links, and during bad visibility (OR=16.15; 95% CI, 3.901-66.881). CONCLUSION: These results will influence the urban traffic police enforcement measures, which will change inappropriate behavior of drivers and protect the least experienced road users.  相似文献   
737.
介绍了采用局部敞开式隔声罩隔音降噪技术治理空分站大型空压机组噪声的治理方案及取得的效果.  相似文献   
738.
- DOI: http://dx.doi.org/10.1065/espr2006.01.002 Background Davide Calamari and his colleagues were among the first to appreciate that vegetation could play a key role in determining the fate and effects of organic contaminants. They conducted pioneering experiments to investigate the uptake of contaminants by plants from the atmosphere and they sought to model the observed phenomena. In the nearly two decades since there has been a marked increase in understanding of these phenomena as a result of both experimental and modelling studies. - Goal. In this study we briefly review our current understanding of chemical partitioning between foliage and air. A model in both fugacity and concentration format is described, based on that of Tolls and McLachlan (1994), in which the leaf is treated as consisting of two layers, a waxy cuticle with an underlying 'reservoir' layer, the cuticle being surrounded by an air boundary layer and containing stomata that provide direct access from the air to the 'reservoir'. The model quantifies the dynamic penetration of a defined chemical into a defined leaf as a function of time. Main Features The model is applied for illustrative purposes to a hypothetical but typical leaf for a set of illustrative chemicals to demonstrate the effect of changes in physical-chemical properties and leaf characteristics. Discussion The results are compared qualitatively with a variety of field and laboratory studies of foliage uptake and clearance of chemicals. Conclusion It is concluded that the model yields results that are generally consistent with observations. It is suggested that with appropriate parameterisation and validation, the model can contribute to an improved understanding of the process of foliage uptake from the atmosphere and to the development of an improved predictive capability.  相似文献   
739.
中小燃煤锅炉脱硫除尘降噪工程实践   总被引:1,自引:0,他引:1  
本文提出了结合我国国情,应采用价宜、实用、效高、稳定、易操作、无二次污染的湿式脱硫除尘装置进行综合治理的主张,并系统阐述了在四川省成都市区内一单位四台燃煤小锅炉脱硫除尘防噪工程的成功实践,证实了上述主张的可行性。  相似文献   
740.
This study assesses the relative dominance of vision and hearing in judgments of environments, and examines whether the sound sensitivity of the judge alters relative sensory dominance. Six sets of four composite (auditory-plus-visual) videotaped environmental displays were created from unisensory visual and auditory components with known levels of evoked affect. These displays, in a 2 (high, low) × 2 (high, low) Pleasure and/or Arousal format, were presented to 70 participants. The results indicate that visual cues dominate auditory cues in judgments of Pleasure, but that the degree of dominance is highly variable. Arousal judgments were not consistently related to visual or auditory cues. Sound sensitivity does not appear to influence the relative dominance of vision.  相似文献   
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