氚是核设施运行过程中释放的放射性物质之一,对人体的内照射危害不仅与其活度有关,而且与氚的化学形态、摄入途径密切相关。针对目前国内涉及氚的控制标准较多,氚化水(HTO)与元素氚(HT)的控制限值均存在不一致的问题,梳理分析了氚浓度...氚是核设施运行过程中释放的放射性物质之一,对人体的内照射危害不仅与其活度有关,而且与氚的化学形态、摄入途径密切相关。针对目前国内涉及氚的控制标准较多,氚化水(HTO)与元素氚(HT)的控制限值均存在不一致的问题,梳理分析了氚浓度控制限值的发展及相关标准的制定依据。根据我国现行辐射防护有关标准,结合国际原子能机构(International Atomic Energy Agency,IAEA)和国际放射防护委员会(International Commission on Radiological Protection,ICRP)出版物中最新的核素氚生物剂量学参数,重新计算了氚的导出空气浓度(Derived Air Concentration,DAC)与水中活度浓度的控制限制值,以期为辐射防护管理标准制定提供参考,并对控制限值的适用对象进行了明确的区分,控制限值的适用对象是人而非设施设备。展开更多
As gradual improvement of living environment and indoor decoration form diversification, the indoor air pollution has become the ＂invisi- ble killer＂ harming human health, and has been listed as one of ten big threa...As gradual improvement of living environment and indoor decoration form diversification, the indoor air pollution has become the ＂invisi- ble killer＂ harming human health, and has been listed as one of ten big threats to human health by the World Health Organization, which also be- came one of hot issues concerned by countries all over the world. In this paper, through the determination of formaldehyde in some houses of Binzhou, the release of formaldehyde with the increase of time was explored; change of formaldehyde in the same residence in different functional areas was analyzed; the influence of the temperature, humidity and plant to formaldehyde content was also analyzed.展开更多
The pedigrees of three sequenced rice cultivars were analyzed to show that a majority of the genetic composition of 'Nipponbare' originates from japonica cultivars while the minority originates from indica cul...The pedigrees of three sequenced rice cultivars were analyzed to show that a majority of the genetic composition of 'Nipponbare' originates from japonica cultivars while the minority originates from indica cultivars. In contrast, '93-11' is derived mainly from indica cultivars with a smaller contribution from japonica cultivars. All ancestors of 'Guang lu ai 4' appeared to be indica lines. A set of molecular markers (46 InDels and 53 SSRs) polymorphic between 'Nipponbare' and '93-11' were examined in 46 typical indica and 47 typical japonica cultivars selected from 443 accessions according to Cheng's index. All cultivars were divided into indica and japonica groups without overlapping when clustered by Cheng's index, InDels and SSRs. Much higher InDel and SSR diversity between groups than within groups implies that the marker polymorphisms between 'Nipponbare' and '93-11' represent a large proportion of inter-subspecific diversity. About 85% of indica cultivars and more than 90% of japonica cultivars were confirmed to have the same PCR banding patterns as '93-11' and 'Nipponbare', respectively. Some polymorphic loci between 'Nipponbare' and '93-11' cannot be validated in other indica and japonica cultivars, either as subspecies-specific but not predominant alleles, or alleles not specific between the two groups. It was concluded that molecular markers developed from sequence polymorphism between 'Nipponbare' and '93-11' often represent inter-subspecific diversity, although some exceptions were sensitive to either particular marker loci or particular cultivars.展开更多
文摘氚是核设施运行过程中释放的放射性物质之一,对人体的内照射危害不仅与其活度有关,而且与氚的化学形态、摄入途径密切相关。针对目前国内涉及氚的控制标准较多,氚化水(HTO)与元素氚(HT)的控制限值均存在不一致的问题,梳理分析了氚浓度控制限值的发展及相关标准的制定依据。根据我国现行辐射防护有关标准,结合国际原子能机构(International Atomic Energy Agency,IAEA)和国际放射防护委员会(International Commission on Radiological Protection,ICRP)出版物中最新的核素氚生物剂量学参数,重新计算了氚的导出空气浓度(Derived Air Concentration,DAC)与水中活度浓度的控制限制值,以期为辐射防护管理标准制定提供参考,并对控制限值的适用对象进行了明确的区分,控制限值的适用对象是人而非设施设备。
文摘As gradual improvement of living environment and indoor decoration form diversification, the indoor air pollution has become the ＂invisi- ble killer＂ harming human health, and has been listed as one of ten big threats to human health by the World Health Organization, which also be- came one of hot issues concerned by countries all over the world. In this paper, through the determination of formaldehyde in some houses of Binzhou, the release of formaldehyde with the increase of time was explored; change of formaldehyde in the same residence in different functional areas was analyzed; the influence of the temperature, humidity and plant to formaldehyde content was also analyzed.
基金Supported by Shanghai Municipal Science and Technology Commission (Grant Nos. 03DJ14014 and 05DJ14008)Chinese Ministry of Agriculture (948 plan) (Grant Nos. 2001-101 and 2006-G-1)Chinese Ministry of Science and Technology (Grant No. 2004CB117204)
文摘The pedigrees of three sequenced rice cultivars were analyzed to show that a majority of the genetic composition of 'Nipponbare' originates from japonica cultivars while the minority originates from indica cultivars. In contrast, '93-11' is derived mainly from indica cultivars with a smaller contribution from japonica cultivars. All ancestors of 'Guang lu ai 4' appeared to be indica lines. A set of molecular markers (46 InDels and 53 SSRs) polymorphic between 'Nipponbare' and '93-11' were examined in 46 typical indica and 47 typical japonica cultivars selected from 443 accessions according to Cheng's index. All cultivars were divided into indica and japonica groups without overlapping when clustered by Cheng's index, InDels and SSRs. Much higher InDel and SSR diversity between groups than within groups implies that the marker polymorphisms between 'Nipponbare' and '93-11' represent a large proportion of inter-subspecific diversity. About 85% of indica cultivars and more than 90% of japonica cultivars were confirmed to have the same PCR banding patterns as '93-11' and 'Nipponbare', respectively. Some polymorphic loci between 'Nipponbare' and '93-11' cannot be validated in other indica and japonica cultivars, either as subspecies-specific but not predominant alleles, or alleles not specific between the two groups. It was concluded that molecular markers developed from sequence polymorphism between 'Nipponbare' and '93-11' often represent inter-subspecific diversity, although some exceptions were sensitive to either particular marker loci or particular cultivars.
