• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>Waste management symposium >DIRECT AND INDIRECT EFFECTS OF MICROBES ON TECHNETIUM INSOLUBILIZATION IN PADDY FIELDS
【24h】

DIRECT AND INDIRECT EFFECTS OF MICROBES ON TECHNETIUM INSOLUBILIZATION IN PADDY FIELDS

机译：微生物在稻田中微生物对不溶血的直接和间接影响

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Direct and indirect effects of microorganisms on technetium insolubilization in water covering waterlogged soils were studied. Seven soils were waterlogged and then the water covering the soils were collected for further tracer experiments. The samples in contact with air were incubated with 95mTcO4 - at 25°C for 4 to 5 days. After incubation, the samples were sequentially separated into four fractions: one insoluble fraction (> 0.2 μm) and three soluble fractions (TcO4 -, cationic, and other forms). The radioactivity of 95mTc in each fraction was measured with a NaI (Tl) scintillation counter. The insolubility of Tc was observed in the untreated samples. The maximum insolubilization radioactivity was 37% of the total radioactivity in P38, which was collected from a paddy field, gray lowland soil. Microscopic observations revealed that bacteria were the dominant species in the insoluble fraction of P38. For the other samples, less than 9% of the Tc was found in insoluble form. In order to clarify biological and nonbiological factor affecting the insolubility, a reducing agent or nutrients were added to the P38 sample. The amount of insoluble Tc was enhanced by the addition of nutrients, while the addition of the reducing agent resulted in a dramatic decrease in the amount of the insoluble Tc. Most of the 95mTcO4 - added to the filtered or autoclaved samples was present in the form of the pertechnetate anion, even in P38. The filtered and autoclaved samples contained metabolites and dead cell particles, respectively. These materials, therefore, did not affect the physicochemical changes in Tc. These results suggest that specific bacteria having the ability to render Tc insoluble even under not strictly anaerobic conditions directly contribute to the insolubility of Tc.
机译：研究了微生物对水覆盖涝土壤中不溶血的直接和间接影响。将七个土壤涝渍，然后收集覆盖土壤的水进行进一步的示踪实验。将与空气接触的样品与95mtCO 4 - 在25℃下温育4至5天。温育后，将样品依次分离成四个级分：一种不溶性级分（>0.2μm）和三种可溶性级分（TCO 4 - ，阳离子和其他形式）。用NaI（TL）闪烁计数器测量每个级分中95MTC的放射性。在未处理的样品中观察到Tc的不溶性。最大不溶化的放射性活度是在P38的总放射性，将其从一个水田，灰色低地土壤收集的37％。显微镜观察显示，细菌是P38不溶性分数中的显性种类。对于其他样品，在不溶性形式中发现小于9％的TC。为了阐明影响不溶性的生物和非生物学因素，将还原剂或营养物加入到P38样品中。通过添加营养素增强不溶性Tc的量，同时加入还原剂导致不溶性Tc的量的显着降低。加入过滤或高压灭菌样品的大部分95mtCO 4 - 即使在P38中也以髓鞘阴离子的形式存在。过滤的和高压灭菌样品分别含有代谢物和死区颗粒。因此，这些材料不会影响TC的物理化学变化。这些结果表明，即使在不严格的厌氧条件下，具有能够使TC不溶性不溶性的特异性细菌直接有助于TC的不溶性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号