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691.
Young AL 《Environmental science and pollution research international》2003,10(2):82-88
The use of irradiation to improve the safety, protect the nutritional benefits, and preserve the quality of fresh and processed foods is a well established and proven technology. Over the past 35 years, the United States Government has invested in the science to confirm safety and in the technology to show application. The United States Department of Agriculture (USDA) and the Food and Drug Administration have approved sources of ionizing radiation for the treatment of foods, and their application to most meats, fruits, vegetables, and spices. Despite the value of this technology to the food industry and to the health and welfare of the public, only minimal application of this technology occurs. This underscores the importance of increasing the public's understanding of radiation risks relative to other hazards. Accordingly, in 1995, the Committee on Interagency Radiation Research and Policy Coordination of the Executive Office of the President made recommendations for the creation of a centralized National Radiation Information Center that would work closely with Federal departments and agencies in responding to public queries about radiation issues and Federal programs. This article updates a commentary published in 1996 (Young 1996). In the past six years, some progress has been made, including the establishment of a government operated Food Irradiation Information Center, and the completion of final rule making by USDA, thus permitting the safe treatment of meats and poultry. Despite these actions, little progress has been made on the public acceptance of this technology. The need for an informed public and for a better understanding of risks, i.e., risk communication, is noted. 相似文献
692.
Feretis E Theodorakopoulos P Varotsos C Efstathiou M Tzanis C Xirou T Alexandridou N Aggelou M 《Environmental science and pollution research international》2002,9(3):163-165
The increase in solar ultraviolet radiation can have various direct and indirect effects on human health, like the incidence of ocular damage. Data of eye damage in residents of three suburban regions in Greece and in two groups of monks/nuns and fishermen are examined here. The statistics performed on these data provides new information about the plausible association between increased levels of solar ultraviolet radiation, air-pollution at ground level, and the development of ocular defects. 相似文献
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对放射源的性质、应用及危害进行了系统的论述,同时联系哈尔滨市放射源安全管理的实际现状,分析了存在的不足和问题.哈尔滨市是黑龙江省核技术应用单位集中地,所拥有的放射源枚数约占全省总数的三分之一,存在的主要问题有:领导对放射源安全管理认识不够、放射管理制度不健全、放射环境保护审批手续不全、放射防护设施不健全、放射源监督管理体制不顺.同时,作者提出了今后放射源安全管理方面的具体对策为:理顺体制、强化日常监督管理、加强放射源安全管理知识宣传教育工作、加强制度建设、加大放射源安全管理执法监督力度. 相似文献
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Effects of the simulated acid rain(AR) and ultraviolet-B(UV-B, 280-320 nm) radiation with a single or two ways simultaneously (AR + UV-B) on the antioxidant enzyme and photosynthesis of the rape seedlings were investigated by the hydroponic culture. The results of static experiment indicated that the tolerance of rape seedling to single stress(AR or UV-B) is stronger than that to dual stresses(AR + UV-B). Furthermore, the dual stresses had additive effect on catalase activity, and a synergistic effect on MDA content, net photosynthesis rate, water use efficiency as well as intercellular CO2 concentration. Meanwhile, it has an independent effect on chlorophyll content, stomatal conductance, and transpiration rate as well as membrane permeability. During 64 h restoration course, the dynamic change in the curves of physiological and biochemical indices were not identical, and none of them show a simple linear variation. According to the static and dynamic experiments, it was found that a responsive sequence of catalase activity, membrane permeability, MDA content and photosynthetic characteristics to the above-mentioned stresses was as follows: AR + UV-B 〉 UV-B 〉 AR. 相似文献
697.
液化气体容器在火灾环境下由于内部压力升高和容器本身强度的下降,爆炸的危险性极大。研究容器在喷射火焰作用的响应规律是预防事故发生的关键。本文研究了由于气体泄漏引起的喷射火焰在有风条件下的火焰形状和温度变化规律,以及对于水平圆柱形容器的热辐射影响,并用编制计算程序进行了数值计算。计算结果表明,容器表面的热辐射随风速、容器表面的位置等因素而变化。风速越大,容器表面的热辐射会减少;轴向距离越大,热辐射减少,周向角度增加,热辐射减少。 相似文献
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面声源的非轴向辐射的近场研究 总被引:1,自引:0,他引:1
本文提出了一种对大面积有壁障面声源非轴向辐射时近场研究的计算方法。在对声场的理论计算中分别考虑了面声源中各点间的干涉和由壁障引起的衍射。并详细介绍了为验证理论计算而进行的缩尺模型实验以及对所得结果的讨论和比较,本研究所得的面声源非轴向辐射时的近场规律对实际处理大面积噪声源辐射时阴影范围的确定有着很好的指导意义。 相似文献