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1.
Introduction Contamination of crops and cropland by fission products as a result of fallout from nuclear explosions and waste from nuclear reactors is a matter of concern. It has been shown (4, 5) that the fission elements yttrium, cerium, zirconium, columbium, tellurium and strontium are absorbed from the soil and translocated in plants only to a limited extent. Of these elements, strontium is absorbed and translocated to the greatest extent. The other elements are apparently more strongly bound to the soil colloid. 相似文献
3.
研究兽药的代谢和残留消除对于指导临床安全用药,保证动物和人的健康具有重要意义。放射性示踪技术在兽药的代谢和残留消除中药物及代谢物定性、定量分析具有准确、可信度高等特点,因此得到广泛应用。本文对近年来放射性示踪技术在兽药代谢、残留消除中的应用进行了综述,概括了放射性示踪技术在研究兽药药动学、代谢以及物料平衡规律的优势,总结了放射性示踪技术在兽药残留靶组织及标示残留物确定等方面的广泛应用及重要意义,旨在为我国未来放射性示踪技术在兽药安全性评估等方面的应用提供理论支持。 相似文献
4.
A. V. Litvinovich O. Yu. Pavlova D. N. Yuzmukhametov A. V. Lavrishchev 《Eurasian Soil Science》2008,41(5):502-508
The scope of stable strontium migration in the light-textured soddy-podzolic soils was determined in columns in a series of simulation experiments. The amount of leached strontium was found to depend on its initial content in the soils, the humus content, and the volume of percolated moisture. The artificial enrichment of soils with strontium increases the losses of this element due to its leaching. However, strontium is not completely removed even upon repeated water percolation. 相似文献
5.
In a long-term field experiment on a medium loamy soddy-podzolic soil at the Chashnikovo Training and Experimental Soil-Ecological Center of Moscow State University, 16.6 kg/ha of strontium were added to the soil with double superphosphate (Pds) over 41 years of its regular application (overall, 3320 kg Pds/ha were applied). As a result, the total strontium content in the soil increased by 1.1–1.3 times in comparison with the control. The changes in the content of the mobile strontium compounds were statistically insignificant. The strontium accumulation in the vetch and oats grown on the plot with the Pds application was 1.4–2.4 times greater than that in the control and in the NK variant. The strontium content in the plants was maximum on the nonlimed plots. Liming, especially in combination with application of organic fertilizers, led to changes in the soil chemical properties controlling the strontium mobility, which resulted in the lower uptake of strontium by the plants. However, the same factors predetermined an increase in the yield of the crops and a more active removal of strontium with the harvested plants. Ten years after the cessation of the fertilization, no increase in the concentration of the strontium in the perennial grasses grown on the plots with the former Pds application was registered. 相似文献
6.
2011年3月日本福岛核电站发生核泄漏事故,释放出大量放射性物质,使周边农田受到直接污染。其中对水稻影响最为严重的放射性核素为放射性铯。分析表明:水稻对铯的吸收是存在差异的,钾肥能有效降低水稻中铯含量,而氮肥会增加其铯含量;距离福岛核电站距离越远其受污染程度越低;土壤中铯的浓度、含钾量、固定铯的能力和耕作表土的厚度都影响着铯的转移;此外,水稻本身的品种也影响着对铯的吸收。水稻去污染的方法包括:利用蓝藻除去表土中放射性铯、对土壤进行深耕及防止水田二次污染等方式来降低土壤本身铯含量;另一方面通过改变土壤粒度分布,向土壤中加入施威特曼石、沸石和蛭石及控制肥料比例等方式来抑制土壤中铯的转移。以上除污染方法的综合应用效果十分显著,福岛县水稻含铯量于2014年已全部低于25 Bq/kg。该研究为中国构建农作物放射性污染特征数据库及相关应急管理提供参考。 相似文献
7.
Yu. N. Vodyanitskii A. T. Savichev A. A. Vasil’ev E. S. Lobanova A. N. Chashchin E. V. Prokopovich 《Eurasian Soil Science》2010,43(7):822-832
The contents of heavy alkaline-earth (Sr and Ba) and rare-earth (Y, La, and Ce) metals have been studied in two technogeochemical
anomalies and in the soils of Perm and Chusovoi. The soils are contaminated with barium, lanthanum, and cerium in the territory
of the Cherepovets technogeochemical anomaly formed due to the atmospheric emissions from the Severstal metallurgical works.
Strontium, barium, and yttrium are accumulated in the soils of the Revda technogeochemical anomaly formed by aerial emissions
from the Mid-Urals copper smelter. The portion of technogenic strontium reaches 43–84% near the metallurgical works, while
that of barium and yttrium, 47–63 and 28–32%, respectively. In Perm, the urban soils are polluted with technogenic alkaline-earth
metals, i.e., strontium and barium, with their content reaching 31–48%. In Chusovoi, the calcareous horizons of the soddy
soils are enriched in strontium and depleted in barium. The eluvial-illuvial distribution of the rare-earth metals is registered
in the soddy-podzolic soil. The soils of the terrace are contaminated with barium. The technozem is contaminated with all
the metals (barium and yttrium, in particular). 相似文献
8.
M. V. Fedorkova E. P. Pakhnenko N. I. Sanzharova 《Moscow University Soil Science Bulletin》2012,67(3):133-136
Under model experiment conditions, the mechanisms of chemical interaction of 90Sr with soil organic matter were established. The radionuclide was introduced in soil examples of main soil-types widespread on the European territory of the Russian Federation. It was found that from 40 to 60% of the radionuclide extracted in exchangeable chemical form. In addition, fulvic acids (FA) (fractions I and Ia) absorbed a significant amount of the radionuclide: 25?C35%. It was shown that 90Sr is available for forming chemical compounds with nonspecific organic matter with molecular weight (M) ranging from 180 to 500 g/mol, without reference to soil type. An essential part of radioactive strontium, 18?C24% (from introduced 90Sr), which was associated with high-molecular fraction (M > 500 g/mol), was detected in chernozems, chestnut soil, and peat soil. In soddy-podzolic soil and light-gray forest soil, it was found mostly (33?C34%) with mineral compounds (M < 180 g/mol). 相似文献
9.
成都经济区放射性环境评价分析研究 总被引：1，自引：0，他引：1
运用区域1/25万土壤化探数据中铀、钍、钾的含量数据,对成都经济区的放射性水平进行了评价。介绍了放射性核素含量分布情况和环境放射性水平,通过成都经济区地质情况和成都经济区放射性环境分布情况,分析了地质条件对成都经济区环境放射性的影响,并初步研究了地质条件影响放射性水平的原因。最后总结了成都经济区地质环境对天然放射性水平分布情况的影响规律:除龙门山褶皱带和峨眉山-瓦山断块少部分地区外,绝大部分地区γ射线内外照射指数都在国家建筑材料放射性核素限量标准控制式的范围内;地质构造、地表出露岩层和地表水对放射性水平有较大的影响。 相似文献
10.
S. V. Mamikhin V. N. Golosov T. A. Paramonova E. N. Shamshurina M. M. Ivanov 《Eurasian Soil Science》2016,49(12):1432-1442
Profiles of vertical 137Cs distribution in alluvial meadow soils on the low and medium levels of the Lokna River floodplain (central part of the Plavsk radioactive spot in Tula oblast) 28 years after the Chernobyl fallout have been studied. A significant increase in the 137Cs pool is revealed on the low floodplain areas compared to the soils of interfluves due to the accumulation of alluvium, which hampers the reduction of the total radionuclide pool in alluvial soils because of radioactive decay. The rate of alluvium accumulation in the soil on the medium floodplain level is lower by three times on average. An imitation prognostic model has been developed, which considers the flooding and climatic conditions in the region under study. Numerical experiments have quantitatively confirmed the deciding role of low-mobile forms in the migration of maximum 137Cs content along the soil profile in the absence of manifested erosion–accumulation processes. 相似文献
11.
In the last report1) the purity of radioactive potassium. which had been produced by 41K (d, p) 42K nuclear reaction and separated from, radioactive anions by the use of ion exchange resin, was tested by means of its decay curve. By this test, it is difficult to distinguish 42K from 24Na contamination, because the half life of radioactive sodium (24Na) is 15.06 hours2) and it is very similar to that of radioactive potassium (42K) which is 12.4 hours. When the nuclear reaction 23Na (d, p) 24Na occurs, the cross section of this reaction for deuterons is about 100 times that of potassium nuclear reaction. In this case the purity of radioactive potassium (42K) could be confirmed by its Gamma-ray spectrum. According to the result, radioactive potassium of high purity was obtained. Potassium phosphate which was double-labeled by this radioactive potassium and imported radioactive phosphorus (32P) was applied to leaves or roots of bean plants. 相似文献
12.
Soler A. Canals A. Goldstein S. L. Otero N. Antich N. Spangenberg J. 《Water, air, and soil pollution》2002,136(1-4):207-224
The use of sulfur and strontium isotopes as tracers forthe source/s of water contaminants have been applied to thewater of the Llobregat River system (NE Spain). Surfacewater samples from June 1997 were collected from theLlobregat River and its main tributaries and creeks. Thechemistry of most stream waters are controlled mainly bythe weathering of Tertiary chemical sediments within thedrainage basin. The largest variation in δ34Svalues were found in the small creeks with values rangingfrom –9.9 to 15‰, whilst in the main river channels valuesranged from 6.3 to 12.4‰. The 87Sr/86Sr ratio fordissolved strontium ranged from 0.70795 for a non-pollutedsite to 0.70882 for a polluted one. Most of the waters withhigh NO3 and low Ca/Na ratio converge to the same87Sr/86Sr value, pointing to dominant pollutantend member contribution or a mixing of pollutants with anisotopic composition around 0.7083–0.7085. Although theconcentration of the natural inputs in the river forsulfate and strontium are high, as a result of the sulfateoutcrops within the geology of the basin, their isotopiccharacteristics suggest that they can be used as adiscriminating device in water pollution problems. Howeverto establish the detailed characteristics of the isotopesas geochemical tools, specific high-resolution case studiesare necessary in small areas, where the inputs are well known. 相似文献
13.
Since the discovery of radioactivity, its effects upon living organisms have attracted many people's interest and attention, and paticularly, since the appearance of the atomic bomb, it has raised very important problems in various fields1). In connection with this, radioactive isotopes have been found to be very useful and important tools for investigation and research in the fields of Biology and Agriculture. 相似文献
14.
15.
In plants, zinc is commonly found bound to proteins. In barley (Hordeum vulgare), major storage proteins are alcohol‐soluble prolamins known as hordeins, and some of them have the potential to bind or store zinc. 65Zn overlay and blotting techniques have been widely used for detecting zinc‐binding protein. However, to our knowledge so far this zinc blotting assay has never been applied to detect a prolamin fraction in barley grains. A radioactive zinc (65ZnCl2) blotting technique was optimized to detect zinc‐binding prolamins, followed by development of an easy‐to‐follow nonradioactive colorimetric zinc blotting method with a zinc‐sensing dye, dithizone. Hordeins were extracted from mature barley grain, separated by SDS‐PAGE, blotted on a membrane, renatured, overlaid, and probed with zinc; subsequently, zinc‐binding specificity of certain proteins was detected either by autoradiography or color formation. The dithizone staining method gave similar reproducibility to the radioactive blotting. The detected zinc‐binding protein was identified as B‐hordein by Western blotting. 相似文献
16.
Göran E. Åberg 《Water, air, and soil pollution》2001,130(1-4):1577-1582
Naturally occurring isotope systems, such as strontium and lead, are very useful for characterizing sources of pollution and producing background information. The phase-out of lead additives to gasoline in Northern Europe has for example not phased out the lead contamination of the environment. The stable lead isotope method shows the contribution from small local sources to the lead contamination of the Oslo air during a period when the combustion of gasoline, the major source of lead contamination, has been decreasing. Wood combustion for domestic heating is one of these polluting sources in Norway. Strontium analyses show that roadsalt from de-icing of a nearby road is accumulated in the soil surrounding an about 4500 year old rock carving. At rainfall this salt is re-dissolved and drained over the rock carving. The impact from the road is confirmed by lead isotopes. Lead and strontium analysis of teeth show the contribution from industry and traffic on todays humans and the differences in nutrient intake during the Medieval era are compared with today. The isotope signatures of the Medieval teeth also show that a person living along the coast can be distinguished easily from a person living in the central parts of the country, and that the Medieval individual mainly lived on locally produce, while the contemporary person to a great degree lives on industrially manufactured food. 相似文献
17.
Hisatomi Harada Koichi Amaha Yoshiyuki Abe Youichiro Kojima Yoshihito Sunaga Tahei Kawachi 《Soil Science and Plant Nutrition》2013,59(6):782-789
AbstractRadioactive cesium (Cs) deposited after the Fukushima Daiichi Nuclear Power Station accident contaminated farmyard manure (FYM) in the wide area surrounding the plant. We conducted a field trial to determine the transfer factor of radioactive Cs to forage corn (Zea mays L.) from soil to which the contaminated FYM had been applied. The main purpose of this experiment was to examine the behavior of the radioactive Cs from contaminated FYM that was incorporated in agricultural fields. Application of FYM containing 3900 Bq kg?1 dry matter (DM) of cesium-137 (137Cs) at a rate of 4.3 kg m?2 increased the 137Cs concentration in the soil by 64 Bq kg?1 dry soil, and in the forage corn by 9.2 Bq kg?1 DM. Therefore, we calculated the transfer factor to corn plants from the soil after application of contaminated FYM to be 0.14. This value is lower than that observed for soil to which uncontaminated FYM had been applied as a control, and it is within the range of reported soil-to-plant transfer factors of 0.003–0.49 listed in the recent parameter handbook by International Atomic Energy Agency. The increase in the radioactive Cs concentration in the corn plants, expressed as the sum of 137Cs and cesium-134 (134Cs), was only 3% of the 2012 provisional tolerance level for cattle roughage in Japan. Even though the application of contaminated FYM did not cause a large change in the radioactive Cs concentration in the corn plants in this trial, such application should be carefully controlled because it increased radioactive Cs concentrations in both soil and forage corn. 相似文献
18.
Recently, studies on foliar application have made splendid development in the field of agronomy and in the fertilizer industry. This fact has some important meanings. First, the conception of fertilizer has gradually changed from the original meaning. "Non-root" parts of plants do take up nutrients from spray and other applications. This conception could definitely be proved by the use of radioactive isotopes as the tracer. Many investigations by use of radioactive isotopes, 14C ( 1 and 2 ) 32P (1, 3, 4, 5, 6, 7 and 8) 42K (9 and 10) 45Ca (10) etc. have since been conducted showing the foliar absorption of nutrients. The second important meaning is the improvement of applica tion methods of fertilizers. By the foliar application method, excellent effects which could not be carried out by the soil application method have been displayed. When fertilizers are applied to leaves of plants in critical times as a supplementary fertilizer, they can be absorbed quickly plentifully into plants. Foliar application of micronutrients, for instance, Mg, Fe, Zn, and Mn have been used succesfully to the deficiencies in plants. Among the macronutrients, phosphorus could perhaps offer more promise as a foliar applied fertilizer, because when phosphatic fertilizers are applied to soil, a large percentage of phosphorus usually becomes fixed in unavailable form to growing plants. On the other hand, especially in a high rainfall area, the application of soluble nitrogen fertilizer to the soil has resulted in low efficiency due to leaching loses (19). So, studies on foliar absorption of urea, phosphorus and micro-nutrients have especially been investigated by many workers. In other cases, there are possibilities that fertilizers can be applied to plants with germicides, insecticides, etc. 相似文献
19.
The accumulation and redistribution of 137Cs in natural ecosystems within the 30-km impact zone of the Smolensk nuclear power plant (SNPP) are analyzed. It is shown
that the radioactive pollution of this territory is mainly due to the Chernobyl-derived radioactive fallout. However, the
radioactive decay of 137Cs from the Chernobyl disaster is partly compensated for by the 137Cs technologic emission from the SNPP. The highest rate of the vertical migration of 137Cs is typical of the bog phytocenoses and deciduous forests. The components of biota may be ranked by their capacity for 137Cs accumulation as follows: higher fungi > mosses > herbs and shrubs > trees. The organisms and their parts that may serve
as bioindicators of the modern radioactive contamination of the territory have been identified. These are the assimilative
organs and bark of the trees, various fern species among herbs, sphagnum mosses and Pleurozium schreberi (among mosses), and Typolius felleus among higher fungi. 相似文献
20.
It was reported in the previous paper1) that rice plants showed retardation of their vegetative growth and decrease of degree of seed setting when their silicon content was extremely low. It was concluded from these facts that silicon might most probably be essential for rice. But physiological functions or behaviours of silicon in plants should be clarified in order to solve this problem completely. Uptake and disttibution of silicon in rice plants were first investigated here, especially compared with phosphorus. A possibility of using silicon radioactive isotope (31Si) for this kind of experiment was also investigated. Although tracer techniques have been greatly developed in elucidating behaviours or physiological functions of various elements in plants, radioactive silicon isotopes have been used very little in this field of science because of this very short half lives. Recently Rothbuhr and Scott 2) reported having used radioactive silicon isotope for uptake experiments by plants in Harwell, England. Since a nuclear reactor (JRR-I) in the Japanese Atomic Energy Research Institute started to work in 1959, radioactive isotopes which have rather short half lives have become available for plant experiments in Japan. Methods of preparation of 31Si for plant experiments were examined and by using 31Si it was studied how silicon was absorbed and translocated by rice and wheat under some particular environmental conditions, and also how the uptake and distribution of it in rice plants were affected by various kinds of metabolic inhibitors. 相似文献