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91.
This article contains the results of research into the impact of implementation of the requirements mentioned in Standard No. OHSAS 18001:2007 to reduce the number of injuries at work and the financial costs incurred in this way. The study was conducted on a determined sample by a written questionnaire survey method in the Republic of Croatia. The objective of the empirical research is to determine the impact of implementation of the requirements of Standard No. OHSAS 18001:2007 to reduce the number of injuries at work and financial costs in Croatia in business organizations that implement these requirements. To provide a broader picture, the research included the collection and analysis of data on the impact of the Standard No. OHSAS 18001:2007 on accidents and fatalities at work. Research findings are based on the analysis of performed statistical data where correlation and regression analysis has been applied.  相似文献   
92.
The clinical presentation of cervical and basilar skull fractures following bead impact is often complex, particularly when multiple noncontiguous fractures are present. Based on the results of 22 human cadaver head-neck impact experiments, a biomechanical framework of spinal injury is developed in which these complex cases may be better understood. This includes the significance of head rebound, head and neck decoupling, cervical spine buckling, cervical injury mechanisms, basilar skull fractures, and cervical spine tolerance. These data also demonstrate that compliant pads significantly increase the risk for spinal injury though they also significantly reduce peak head force and the head injury criteria (p < 0.04). On the basis of these observations, we hypothesize that impact injury should be modeled as the dynamic response of two large masses, coupled by a segmented curved beam-column composed of seven small masses with interposed nonlinear viscoelastic flexibility elements.  相似文献   
93.
通过对超临界锅炉几种常用的铁素体钢及奥氏体钢高温换热管进行取样分析研究,得到了几种材质在运行中产生的氧化皮的结构特征和剥落规律。  相似文献   
94.
葡多酚对口服乙醇小鼠肝细胞PCNA和Bcl-2表达的影响   总被引:1,自引:1,他引:0  
为观察葡多酚(GPC)对小鼠乙醇性肝损伤的防护作用,将每天经口灌胃给予4 g·(kg·bw)-1乙醇的小鼠同时分别给予不同剂量的GPC,30 d后处死小鼠;取肝组织用MTT法检测各组小鼠肝细胞的增殖活性,用免疫组化法和图像分析方法检测PCNA和Bcl-2表达水平.结果显示:GPC高剂量组16 h的肝细胞增殖活性为0.4...  相似文献   
95.
为全面准确地掌握人机交互作业过程中人与机器人在安全性方面的研究进展,把提高机器人安全性的策略归纳为3种方法,分别称为事前预防主动控制、关节柔顺设计和用黏弹性材料包裹连杆,阐述了每种方法评价机器人安全性的主要性能指标。通过对比各种实现方法的设计思想和结构组成方案,总结出各种方法的优缺点和存在的主要问题。事前控制的关键在于信息的全面性和控制的实时性;事后控制方法的主要问题则只能在一定程度上减缓撞击的伤害程度,而无法从根本上保证人的安全性。结果表明,到目前为止仅靠单一手段和方法还不能彻底解决机器人安全性问题,要多种手段相结合,高度重视影响安全性的主客观因素,把提高机器人安全性的理念贯穿于机器人设计的各个环节。  相似文献   
96.
Problem: Pedestrian injury is a major hazard to the health of children in most developed countries, including Australia. In a previous study it was found that parental road risk perception is a significant factor associated with their modeling of safe behavior as pedestrians. This study aimed to investigate factors that affect parental road risk perception. Method: This cross-sectional population-based randomized telephone survey aimed to study factors associated with risk perception on pedestrian road safety among parents with young children aged 4–12 years. Results: Five factors were found to be significantly associated with parental risk perception. They included age of child, sex of parent, employment of parent, living environment, and previous injury experience. The results suggested that the age of the child contributed greatest to the variance explained by the regression model. However, other factors remained significant even after adjusting for each other. Discussion: Results were discussed in light of the design and development of childhood pedestrian road safety campaigns. Impact on industry: Parental risk perceptions determine their safe road modeling behavior. In this study, significant factors that affect parental road risk perception have been identified. The information obtained can be used in the design of road safety programs that aim at changing the road risk perception of parents.  相似文献   
97.
工伤保险与安全管理   总被引:1,自引:1,他引:0  
从我国安全管理实际出发,分析了借助于工伤保险的经济杠杆作用实现国家对企业安全管理制约机制的必要性,并对建立制约机制有关的指标体系及综合评估模型,以及该机制实现等问题进行了深入探讨.  相似文献   
98.
Bioaccumulation of heavy metals in fishes from Taihu Lake, China   总被引:9,自引:0,他引:9  
The Cr,Zn,Cu,Cd,Pb contents were determined in Cyprinus carpio Linnaeus,Carassius auratus Linnaeus,Hypophthalmichthys molitrix and Aristichthys nobilis,which were caught from Meiliang Bay,Taihu Lake,a large,shallow and eutrophic lake of China.The results showed that:(1)the Cr,Cu,Pb,Cd contents in the edible parts of the four fish species were much lower than Chinese Food Health Criterion(1994),but the Zn contents were higher than the Criterion;(2)Cd contents were the highest in the liver of fish,Pb contents were almost the same in all organs of fish,Cr contents mainly enriched in the skin and gonads,Zn contents were the highest in the gonad(♀),and Cu contents were the highest in the liver;(3)the total metal accumulation was the greatest in the liver and the lowest in the muscle.The total metal accumulation was the highest in C.auratus L.This investigation indicated that fish products in Taihu Lake were still safe for human consumption,but the amount consumed should be controlled under the Chinese Food Health Criterion to avoid excessive intake of Zn.  相似文献   
99.
酸雨与镧对大豆幼苗生长的复合伤害效应研究   总被引:2,自引:0,他引:2  
梁婵娟  潘丹云  徐秋荣  周青 《环境科学》2010,31(7):1652-1656
为探索酸雨与稀土镧对大豆幼苗生长的复合影响及其内在机制,以重要油粮作物大豆(Glycine max)为材料,研究在模拟酸雨pH分别为3.0、3.5、4.5与稀土镧La(Ⅲ)浓度分别为60、100和300mg·L-1处理下大豆幼苗生长及光合作用的变化.结果表明,相对单一酸雨与镧处理,酸雨与La(Ⅲ)复合处理组中大豆幼苗的生长受抑制程度增大,两者呈协同效应,且pH越低,La(Ⅲ)浓度越高,抑制效应越明显.光合参数的变化规律与生长指标近同,相同处理组各光合参数的降幅不一致,其中最大荧光(Fv/Fm)和叶绿素含量(Chl)的降幅范围分别为9.53%~22.75%和9.14%~24.53%,较净光合速率Pn(22.78%~84.7%)、希尔(Hill)反应速率(15.52%~73.38%)和Mg2+-ATPase活性(14.51%~71.54%)小,表明各光合参数对2个胁迫因子的敏感程度存在差异.进一步相关性分析发现,Pn变化主要受Hill反应速率与Mg2+-ATPase活性的影响,而Chl、Fv/Fm次之.表明酸雨与La(Ⅲ)对植物光合过程各环节的作用机制不同,光合作用受阻是影响植物生长的重要因素之一.  相似文献   
100.
植物重金属伤害及其抗性机理   总被引:196,自引:2,他引:196  
讨论了二个问题:(1)重金属对植物伤害效应及伤害机理。其中包括重金属对植物细胞质膜透性,水分代谢、光合作用、呼吸作用、碳水化合物代谢、氮素代谢、核酸代谢、植物激素等生理生化过程,生境以及矿质营养的伤害效应,在伤害机理中讨论了植物体内原有的离子平衡系统,大分子物质活性和自由基与伤害的关系。(2)植物对重金属抗性及抗性机理。其中包括植物对重金属的抗性概念,例证,分类,抗性机理包括植物限制重金属离子吸收,重金属与体外分泌物结合,重金属的排除,根系富集,与细胞壁结合,在液泡中积累,形成类-金属硫蛋白或植物络合素,加强抗氧化系统等与植物抗性的关系,参85  相似文献   
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