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1.
三角帆蚌对水体Cr,Pb和Cd的净化与吸收   总被引:14,自引:0,他引:14       下载免费PDF全文
三角帆蚌(Hyriopsis cumingii Lea)对水体Cr,Pb,Cd污染有明显的净化能力,持续处理12d,能使水体Cr,Pb,Cd含量分别下降83%,77.6%和72%。蚌体的斧足、鳃、外磁膜、体表粘液、肝脏、肠道和生殖腺等组织对3种污染物的吸收和富集作用不尽相同,其中分别以体表粘液、鳃和肝脏最为显著。3种污染物进入蚌体的速度很快,其组织吸收量一般在第3天即可达到较高水平。进入蚌体的污染物,可在组织转移和重新分布。研究结果为生物治理Cr,Pb,Cd等重金属污染积累了资料。  相似文献   
2.
可剥离膜去除不锈钢表面铀污染的研究   总被引:4,自引:0,他引:4  
退役的核设施中不锈钢制件表面附着的放射性污染物 ,必须经去污处理后才能回收利用。铀是核工业中最常见的污染放射性元素 ,而不锈钢是核设施中最常用的耐腐蚀金属材料 ,由于以UO2 +2 状态存在的铀 (Ⅵ ) ,在空气和自身的辐射作用下 ,将逐渐转变为不同的氧化物。采用酸性去污液对不锈钢表面铀污染进行浸泡和擦试去污的方法 ,可以有效的除去不锈钢表面铀污染[1] 。但因浸泡需大量的去污液 ,随之产生大量的带有放射性的废液 ,对这些废液还必须经进一步的浓缩———固化处理。擦试法虽产生固体废物 ,但去污操作麻烦 ,难以对大批量、形状复杂…  相似文献   
3.
Effect of gamma radiation on microbial population of natural casings   总被引:1,自引:0,他引:1  
The high microbial load of fresh and dry natural casings increases the risk of meat product contamination with pathogenic microorganisms, agents of foodborn diseases.

The aim of this work is to evaluate the killing effect of gamma radiation of the resident microbial population of pork and beef casings, to improve their hygiene and safety.

Portions of fresh pork (small intestines and colon) and dry beef casings were irradiated in a Cobalt 60 source with with absorbed doses of 1,2,5 and 10 kGy.

The D10 values of total aerobic microorganisms in the pork casings were 1.65 kGy for colon and 1.54 kGy for small intestine. The D10 value found in beef dry casings (small intestine) was 10.17 kGy. Radurization with 5 kGy was able to reduce, at least, 6 logs the coliform bacteria in pork casings. The killing effect over faecal Streptococci was 4 logs for pork fresh casings and 2 logs for beef dry casings. Gamma radiation with 5 kGy proved to be a convenient method to reduce substantially the microbial population of pork fresh casings. Otherwise, the microbial population of beef dry casings still resisted to 10 kGy.  相似文献   

4.
Several thousand tons of medical herbs are produced annually by pharmaceutical industry in Poland. This product should be of highest quality and microbial purity. Recently, chemical methods of decontamination are recognized as less safe, thus irradiation technique was chosen to replace them in use. In the Institute of Nuclear Chemistry and Technology the national program on the application of irradiation to the decontamination of medical herbs is in progress now. The purpose of the program is to elaborate, on the basis of research work, the facility standards and technological instructions indispensable for the practice of radiation technology.  相似文献   
5.
Abstract

Possibilities of using a new generation of sorbents have been investigated. Polymers of spatial-globular (spherulitic) structure (RGS polymers) have been tested to separate Cs, Sr and rare earth elements – which can also be radioactive contaminants – from different waters.

RGS polymers are both, solids and highly-disperse systems being extremely permeable to fluids and gases with low pressure decline. They were currently used to clean industrial waste-water.

It is shown that these polymers can be used successfully to separate radionuclides. Polymers RGS-81 and RGS-112 have high distribution coefficients for CS, Sr, Sc, the lanthanide series and Hf in weakly acid solutions. In HF solutions, Sc and Hf can be separated from Cs, Sr and the lanthanides.  相似文献   
6.
洗消设备配置问题是场外核应急准备工作的重要环节之一,论文根据核辐射洗消过程运行特点,考虑系统内人群密度对洗消进程的影响关系,建立洗消系统系统动力学模型。在不同核辐射超标率场景中,设计不同设备配置方案,模拟并观察系统内等待人数和总洗消时间的变化。仿真结果表明,检测I设备与洗消设备的配置数量及比例,影响洗消进度;在综合考虑设备投入和洗消站占地面积的条件下,该方法可为场外核应急洗消设备配置提供决策依据。  相似文献   
7.
Abstract

The problem concerning qualification of food originated from animals irradiated and contaminated with 137caesium appeared especially after the Chernobyl accident. So, it was a reason to undertake respective studies on 108 rabbits divided into three groups: group I – non-irradiated rabbits, group II – irradiated with a dose of 103 mCkg?1 (400 R), group III – irradiated with a dose of 206 mCkg?1 (800 R). All animals were contaminated intragastrically with an aqueous solution of 137CsCl. After slaughter samples of the muscles were cured in 1, 3, 5, 10, and 15% brine or were cooked for 2 hrs. In the case of curing the radioactivities of meat and brine, and the concentrations of salt in cured meat were estimated after 7, 14, and 21 days. The radioactivities of cooked meat, broth, and condensed water vapour were estimated after 1 and 2 hrs. Taking into account the decrease of the radioactivities, duration of curing, and concentrations of salt in cured meat the optimum results were achieved when the meat from non-irradiated rabbits was cured for 7 days in 3% brine, and that of irradiated rabbits in 5% brine with regard to a lower stability of this meat. The decontamination effectiveness of cooking was similar in all examined rabbits. Radiocaesium penetrates into the brine or broth and escapes with water vapour thereafter.  相似文献   
8.
The catalytic methanolysis of the chemical warfare nerve agents soman, sarin, and VX was investigated by using Cu or Zn complexes. Although VX withstood decontamination, the decomposition yield being around 96%, the soman and sarin deposited on different surfaces were almost fully destroyed under ambient conditions. The catalytic tests performed on a wide range of contaminated surfaces confirm the activity of the investigated catalytic systems, these complexes being suitable, from an economical point of view, for use in the formulation of a possible decomposition kit with military or civilian applicability.  相似文献   
9.
In this work, graphene oxide (GO)‐loaded agarose hydrogel was transferred into oil such as hexadecane via stepwise solvent exchange with no chemical modification of the GO hydrophilic surface and the agarose network. After transfer, the GOs, loaded in the agarose network, could effectively and efficiently adsorb lipophilic dyes in oil via hydrogen bonding between the polar groups of the GOs and the dyes. The maximum adsorption capacity was 355.9 mg g?1 for Nile red for instance, which is substantially larger than that of pristine agarose hydrogel and hydrophilic GO powder. The dye concentration for effective adsorption can be as low as 0.5 ppm. Thus, the present work demonstrates the promising potential of using hydrophilic adsorbents for efficient removal of polar impurities from oil.  相似文献   
10.
涂膜超声及涂膜电解对固体表面铀的去污研究   总被引:3,自引:0,他引:3  
制备了高分子可剥离去污膜液,确定了涂膜液中各组分最佳含量,对固体表面核素的去除研究结果表明:在金属表面采用涂膜电解去污、非金属光滑固体表面采用直接涂膜去污、非金属粗糙固体表面采用涂膜超声去污工艺,其去污率均可达99%以上,优于其他方法。  相似文献   
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