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721.
Árpád Ambrus Zsuzsannna Horváth Júlia Szenczi-Cseh 《Journal of environmental science and health. Part. B》2018,53(6):404-410
ABSTRACTThe effects of the spread of residue concentrations in the samples derived from the selected supervised trials and the number of trials were studied on the magnitude and uncertainty of the short-term dietary intakes calculated with the proposed new procedure (IESTIp) and that one used currently by the FAO (Food and Agriculture Organization) and WHO (World Health Organization) Joint meeting on Pesticide Residues (JMPR) (IESTIc). The residue data of 10 pesticides were obtained from supervised trials conducted on apples and pears. The methods described in Part I were used for the calculations of the uncertainty. The results indicate that the ratio of IESTIP to IESTIc (φIESTI) is directly proportional to the ratio of the estimated maximum residue level (MRL), recommended by the JMPR; to the highest residue (HR) observed in supervised trials, and it may have a wide range depending on the particular conditions. The φIESTI becomes greater with the increase of the difference between the mrl or maximum residue limit (MRL, established by the Codex Alimentarius Commission, CAC) and HR, and becomes smaller if the difference between the large portion (LP) and unit mass (U) decreases. The φIESTI ranged between 2 and 5.1 in the 16 cases examined indicating that the IESTIp calculation method leads to higher intake estimates. The ratio of CVIESTIp and CVIESTIc ranged typically between 0.62 and 1.71. It rapidly increased up to 12 trials. For a larger number of trials, the ratio remained practically constant (1.69–1.71). The processing factor (PF) equally affects the MRL and HR values, therefore, it will not practically influence the φIESTI. The uncertainty of the estimated median residues depends on the spread and number of values in the residue datasets, which affects the uncertainty of the conversion factor (CF) and subsequently the uncertainty of the estimated IESTIp. Residue values obtained from minimum nine independent trials are required for the correct calculation of the 95% confidence intervals of the calculated median residues. The uncertainty of the analytical results directly affects the median, HR values and indirectly the calculated mrl and the MRL derived from it. Therefore, it should also be considered for the calculation of the combined uncertainty of the conversion factors. For the correct interpretation of the results of dietary exposure calculations, the upper 95% confidence limit of the short-term intake should also be considered. However, it is not the current practice of regulatory agencies or JMPR. 相似文献
722.
This research utilizes real operating data from a tire plant operating in Central Taiwan to investigate the carbon footprint emissions (CO2e) involved in producing the electric bicycle. The simulation results are based on the PAS 2050 standard using the SimaPro 7.3 software tool. Our results show the total carbon footprint emissions of 1.2-kg tire for the electric bicycle weighing 4.53-kg CO2e, composed of 2.63-kg CO2e from raw tire materials stage, 1.295-kg CO2e from tire manufacturing stage, and 0.605-kg CO2e from tire transport stage. An international certified organization, British Standard Institute (BSI), verified the accuracy of our results as 98.7%. We found that carbon emissions at the raw materials stage were higher than that for the other two stages – manufacturing and transportation. Carbon black was determined as the maximum source of carbon emissions at the raw material stage. To reduce the tire plant carbon emissions, this paper recommends using graphene to replace carbon black. Graphene has been reported by many researches to improve the properties of rubber products. From our simulation results, the carbon footprint emissions of 4.56-kg CO2e of the origin tire plant uses 0.456-kg carbon black to produce 1.2-kg electric bicycle tires. This can be reduced to 4.29 (5.92%), 4.03 (11.62%), 3.75 (11.76%), and 3.49-kg CO2e (23.46%) by using graphene to replace carbon black 25, 50, 75, and 100 wt% respectively. If we focus only on 0.456-kg carbon black producing 1.08-kg CO2e, the reduced carbon footprint will be 0.812 (24.81%), 0.547 (49.35%), 0.28 (74.07%), and 0.0128-kg CO2e (98.81%) by using graphene to replace carbon black 25, 50, 75, and 100 wt% respectively. From our analysis, graphene replacing carbon black can reduce carbon footprint. This has not been published previously and provides a direction for the tire plant to save carbon emissions. 相似文献
723.
724.
国家行政征用海域使用权补偿标准法律问题探讨 总被引:1,自引:0,他引:1
根据2002年开始实施的《中华人民共和国海域使用管理法》,在海域使用管理法中关于国家行政征用海域使用权、进行清海补偿标准的未作规定,只在渔业管理法中规定参照土地管理法的补偿标准进行补偿,因此,各沿海地区确定征用补偿标准缺乏统一标准。本文根据国家行政征用海域使用权补偿存在的无专门系统的行政征用补偿法、海域征用补偿程序混乱、海域征用补偿救济手段不完善、海域管理适用法律冲突和安置补偿与生产损失补偿混淆在一起等问题进行了探讨,对于完善国家行政征用海域补偿制度提出了法律建议。 相似文献
725.
通过实验验证了盐酸副玫瑰苯胺分光光度法测定大气中SO2的标准方法中,用EDTA代替CDTA去掩蔽金属离子的干扰是可行的,即方便,又经济。 相似文献
726.
727.
孔昭音 《环境监测管理与技术》2000,12(4):39-40
就现行的某些环境保护国家标准中存在的问题,提出了在制定或修订标准时,所用术语表达应准确,数字表达应统一采用中文数字或统一采用阿拉伯数字、内容相关标准就叮关性和统一性的建议。 相似文献
728.
对铬及其化合物工业项目排放废气中特征污染物的监测方法和评价标准问题进行探讨,提出了验收监测应参考《大气污染物综合排放标准》(GB 16297—1996)的建议;通过对监测数据的合理性和逻辑性分析,提出了现场监测和数据审核的注意事项,应严格监控工况,并详细记录关键设备运行参数;提出应把废气中六价铬作为特征污染物控制指标,并结合新颁布的《环境空气质量标准》(GB 3095—2012)中对六价铬的要求,确定合理的排放限值,并研究适合的配套监测方法,为后续铬及其化合物工业污染物排放标准以及特征污染物监测方法的制修订提供技术依据。 相似文献
729.
730.
简述了国内环境标准发展趋势,以及国内地方环境标准制订情况,分析了江苏省地方标准现状及问题。提出,应完成现有地方标准修订备案;重点制定新兴行业和大气污染控制标准;加强技术规范、技术政策的制定和编制;建立完善的标准执行与反馈机制。 相似文献