内江市磷肥厂磷矿石,磷肥样品中天然铀,镭—226含量分析

本文报道了内江市８个磷肥的磷肥及其原料矿石中天然铀，＾２２６Ｒａ含量水平，其结果为，磷肥样品中＾２２６Ｒａ含量２４５．８±１１２．９Ｂｑ．ｋｇ＾－１，天然铀含量２７．２±１６．４ｐｐｍ；磷矿石样品中＾２２６Ｒａ含量４０７．６±９４．３Ｂｑ．ｋｇ＾－１，天然铀含量３１．４±２１．０ｐｐｍ。     

井矿盐开发所致的辐射水平

本文报道了自贡市井矿盐开发所致的辐射水平。井矿盐开发的主要废弃物－卤泥中＾２３８Ｕ，＾２２６Ｒａ，＾２３２Ｔｈ的天然放射性核素比活度比四川省土壤中相应核素平均值高１－２个数量级，且造成卤泥堆积场和局部生产环境陆地γ辐射剂量率高出自贡市环境陆地γ辐射平均值的２．０－４８．３倍，最主超过１６５倍。部份卤泥和盐厂附近江河排放口底泥中天然放射性废物标准。     

微生物传感器技术原理及其在水环境监测中的应用

微生物传感器技术产生于７０年代，并且，已在水环境监测中得到应用，例如，ＢＯＤ、ＮＨ３、ＮＨ４＾＋、ＮＯ２＾－、ＮＯ３＾－等项目分析；毒物测定和毒性评价；致突变物的筛选等。实践证明，该项技术具有快速、灵敏、易于自动控制、成本低廉等优点；可以相信，它必定会越来越多的应用于环境监测。     

硫化矿石自燃倾向性评价的SVM识别模型

为了准确地评价硫化矿石的自燃倾向性,应用Logistic回归分析理论分析主要矿物及其含量、氧化速度常数平均值、自热点、自燃点4项指标与硫化矿石自燃倾向性等级之间的关系,选取氧化速度常数平均值和自热点作为特征指标,建立硫化矿石自燃倾向性评价的支持向量机(SVM)识别模型;以14组硫化矿自燃倾向性实测数据作为学习样本进行训练,建立相应的分类函数;利用回代估计法进行回检,再利用训练好的模型对6组现场实测样本的硫化矿石自燃倾向性进行识别。结果表明:对硫化矿石自然倾向性等级分类产生主要影响的指标是氧化速度常数平均值、自热点,建立的分类方程具有良好的预测效果,而主要矿物、含量和自燃点与分类关联性不大。     

新疆哈密地区食品中^210Pb含量及所致居民内照射剂量

新疆哈密地区食品中~（２１０）Ｐｂ含量及所致居民内照射剂量徐红，张聚敬（新疆维吾尔自治区卫生防疫站乌鲁木齐８３００１１）“‘Ｐｈ是“‘Ｕ、’‘’Ｒａ和“‘Ｒｎ的衰变产物。广泛分布于自然界中，属亲骨性元素之一。它除本身的生物效应外，又是人体内’“Ｐ。的?..     

雨水中S（IV）浓度和氧化速率的测定

本文介绍了日本横滨雨水中Ｓ（ＩＶ）浓度和氧化速率的测定方法：Ｓ（ＩＶ）在雨水中的氧化反应一组反应；Ｆｅ＾３＋和Ｍｎ＾２＋离子对雨水中Ｓ（ＩＶ）的氧化有强的催化作用；Ｓ（ＩＶ）的浓度是０．８～２３．５μｍ和氧化率常数０．１２～３．３小时＾－１。     

几种核素在土壤—生物—人体间的积累和转移

本文对Ｕ，Ｋ，＾１３７Ｃｓ，＾９０Ｓｒ等几种核素在土壤－水稻，土壤－茶叶，土壤－蔬菜之间以及水－鱼间的转移情况进行了研究；并考虑到这些核素含量较高的食品（如茶叶、黄豆）不直接全部食入人体，因此，根据人们的饮茶习惯及豆制品（水豆腐）的加工过程进行模拟，对其向人体转移的参数进行了实验研究。由上述实验结果给出了转移参数及相关方程。     

示差脉冲阳极溶出伏安法测定中药川附子痕量铅镉

本文报道了以ＨＮＯ３－ＨＣｌＯ４湿法消化、醋酸盐介质法差脉冲阳极溶出伏安法测定中药川附子中的铅镉。样品中铅镉含量分别在０．２－０．４μｇ．ｇ＾－１、０．０３－０．１６μｇ．ｇ＾－１,回收率９０－１１０％。     

涪陵地区农田径流水体中三氮含量及分布特征

本文在涪陵地区大面积和定点采集了农田径流水样品，测定了径流水体中的三氮含量。探讨了径流水体三氮随产流时间的变化，分析了干旱时间，水体流动等因素对三氮含量的影响。结果表明，干旱时间，径流水体流动对三氮含量有一定的影响。经统计分析，涪陵地区农田径流水体中的ＮＨ３－Ｎ，ＮＯ３＾－－Ｎ，ＮＯ２＾－－Ｎ和Ｔ－Ｎ含量分别为０．８４０，０．９７０，０．１０７和２．０７ｍｇ／ｌ。     

名词解释

采矿贫化率:又称品位(指单位体积或单位重量的矿石中有用组分或有用矿物的含量)降低率。采出矿石品位对原矿品位的降低数与矿体(或矿块)平均品位的百分比,是检查采矿工作质量和分析采矿方法是否合理的一项重要经济技术指标。     

Phosphogypsum amendment effect on radionuclide content in drainage water and marsh soils from southwestern Spain

Phosphogypsum (PG) is a residue of the phosphate fertilizer industry that has relatively high concentrations of 226Ra and other radionuclides. Thus, it is interesting to study the effect of PG applied as a Ca amendment on the levels and behavior of radionuclides in agricultural soils. A study involving treatments with 13 and 26 Mg ha(-1) of PG and 30 Mg ha(-1) of manure was performed, measuring 226Ra and U isotopes in drainage water, soil, and plant samples. The PG used in the treatment had 510 +/- 40 Bq kg(-1) of 226Ra. The 226Ra concentrations in drainage waters from PG-amended plots were similar (between 2.6 and 7.2 mBq L(-1)) to that reported for noncontaminated waters. Although no significant effect due to PG was observed, the U concentrations in drainage waters (200 mBq L(-1) for 238U) were one order of magnitude higher than those described in noncontaminated waters. This high content in U can be ascribed to desorption processes mainly related to the natural adsorbed pool in soil (25 Bq kg(-1) of 238U). This is supported by the 234U to 238U isotopic ratio of 1.16 in drainage waters versus secular equilibrium in PG and P fertilizers. The progressive enrichment in 226Ra concentration in soils due to PG treatment cannot be concluded from our present data. This PG treatment does not determine any significant difference in 226Ra concentration in drainage waters or in plant material [cotton (Gossipium hirsutum L.) leaves]. No significant levels of radionuclides except 40K were found in the vegetal tissues.     

Radiological impacts of phosphogypsum

This study was carried out to assess the radiological impact of Syrian phosphogypsum (PG) piles in the compartments of the surrounding ecosystem. Estimating the distribution of naturally occurring radionuclides (i.e. (226)Ra, (238)U, (232)Th, (210)Po and (210)Pb) in the raw materials, product and by-product of the Syrian phosphate fertilizer industry was essential. The data revealed that the concentrations of the radionuclides were enhanced in the treated phosphate ore. In PG, (226)Ra content had a mean activity of 318 Bq kg(-1). The uranium content in PG was low, ca. 33 Bq kg(-1), because uranium remained in the phosphoric acid produced. Over 80% of (232)Th, (210)Po and (210)Pb present partitioned in PG. The presence of PG piles did not increase significantly the concentration of (222)Rn or gamma rays exposure dose in the area studied. The annual effective dose was only 0.082 mSv y(-1). The geometric mean of total suspended air particulates (TSP) ca. 85 μg m(-3). The activity concentration of the radionuclides in filtrates and runoff waters were below the detection limits (ca. 0.15 mBq L(-1) for (238)U, 0.1 mBq L(-1) for (232)Th and 0.18 mBq L(-1) for both of (210)Po and (210)Pb); the concentration of the radionuclides in ground water samples and Qattina Lake were less than the permissible limits set for drinking water by the World Health Organisation, WHO, (10, 1 and 0.1 Bq L(-1) for (238)U, (232)Th and both of (210)Po and (210)Pb, respectively). Eastern sites soil samples of PG piles recorded the highest activity concentrations, i.e. 26, 33, 28, 61 and 40 Bq kg(-1) for (226)Ra, (238)U, (232)Th, (210)Po and (210)Pb, respectively, due to the prevailing western and north-western wind in the area, but remained within the natural levels reported in Syrian soil (13-32 Bq kg(-1) for (226)Ra, 24.9-62.2 Bq kg(-1) for (238)U and 10-32 Bq kg(-1) for (232)Th). The impact of PG piles on plants varied upon the plant species. Higher concentrations of the radionuclides were recorded for grass in comparison to broad-leaved plants. Among the species that grow naturally on PG piles, Inula, Ecballium and Polygonium may be radionuclides accumulators. A determined effort is needed at a national level to achieve a common and coherent approach to regulate PG piles or to consider it a resource material rather than waste or residue.     

四川原煤及其废渣与制品放射性的测试分析

本文介绍了四川原煤及其废渣与制品的γ辐射剂量率、附加γ辐射人均年有效剂量量。同时,用低本底Ge(Li)多道γ能谱仪测定了原煤、矸粉与矸砖,煤渣与煤渣砖、粉煤灰及粘土砖等样品中的天然放射性核素~(238)U,~(232)Th,~(226)Ra,~(40)K的比活度。经比较和研究,找出了这些物质的放射性水平及它们彼此之间的规律。     

RADIUM - 226 IN GROUND WATER OF WEST CENTRAL FLORIDA1

ABSTRACT: Principal U.S. phosphate production is from central Florida where mining, processing, and waste disposal practices intimately associate the industry with water resouces. Available radium-226 data from 1966 and from 1973–1976 in mined and unmined mincralized areas and nonmineralized areas in the primary study area in Polk, Hardee, Hillsborough, Manatee, and De Soto counties were studied using log-normal probability plots and nonparametric statistical tests for significant difference as functions of time, depth, and location. Plots of radium in the water table and Floridan aquifers for mineralized and nonmineralized areas indicate that neither phosphate mineralization nor the industry is a probable factor. For the Lower Floridan aquifer, three separate radium populations are indicated with geometric means of 0.7, 3, and 10 pCi/1. Geometric mean radium-226 content of the water table aquifer is 0.17 pCi/1. Radium in the Floridan aquifer in Manatee and Sarasota Counties is elevated relative to that in the water table and in other areas of Florida. For Sarasota County, geometric mean radium content of the water table is 15 pCi/l versus 7.5 pCi/l in the Floridan. Potential sources include shallow phosphate sediments and monazite sands and possibly crystalline basement rocks or other strata unrelated to phosphatic zones of current economic interest. The existing radium-226 data base is rather marginal in terms of number and spatial distribution of analyses, particularly for the water table and Upper Floridan aquifer. Existing radium data do not substantiate widespread contamination of ground water as a result of the phosphate industry. However, local contamination associated with specific operations has occurred.     

Irrigated mountain meadow fertilizer application timing effects on overland flow water quality

Nonpoint-source pollution from agricultural activities is currently the leading cause of degradation of waterways in the United States. Applying best management practices to flood-irrigated mountain meadows may improve agricultural runoff and return flow water quality. Prior research has focused on fertilizer use for increased hay yields, while few studies have investigated the environmental implications of this practice. We examined the effects of fertilizer application timing on overland flow water quality from an irrigated mountain meadow near Gunnison, Colorado. Application of 40 kg phosphorus (P) and 19 kg nitrogen (N) ha(-1) using monoammonium phosphate (11-52-0, N-P-K) fertilizer to plots in the fall significantly reduced concentrations of reactive P and ammonium N in irrigation overland flow compared with early or late spring fertilization. Reactive P loading was 9 to almost 16 times greater when fertilizer was applied in the early or late spring, respectively, compared with in the fall. Ammonium N followed a similar trend with early spring loading more than 18 times greater and late spring loading more than 34 times greater than loads from fall-fertilized plots. Losses of 45% of the applied P and more than 17% of the N were measured in runoff when fertilizer was applied in the late spring. These results, coupled with those from previous studies, suggest that mountain meadow hay producers should apply fertilizer in the fall, especially P-based fertilizers, to improve hay yields, avoid economic losses from loss of applied fertilizers, and reduce the potential for impacts to water quality.     

日本福岛核事故后四川省部分生态系统和食物链的γ核素放射性水平调查

本文调查和掌握了四川省部分生态系统中放射性水平,分析了日本福岛核泄漏事故中放射性核素对四川省主要环境介质的影响和放射性核素的迁移和富集情况,了解此次事故对部分食物链和生态系统的影响程度。对气溶胶、沉降物、土壤、植物、动物、人类食物这一链条样品中的238U、232Th、226Ra、40K、137Cs、131I 6种放射性核素进行检测,结果表明,天然放射性核素238U、232Th、226Ra、40K的检测结果均属于环境正常水平,人工放射性核素137Cs、131I低于仪器检出限。所有样品的检测结果均符合相关国家标准,与环境背景值相当,日本福岛核事故在短时间内,未对四川省生态环境和食物链造成放射性影响。     

Critical analysis of the waste management performance of two uranium production units in Brazil--part II: Caetite production center

This paper discusses the environmental waste management of the Heap-Leach Uranium Production Facility of Caetité located in a semi-arid region in Brazil. A comparison is made with the first uranium production site of the country located in Poços de Caldas. It is demonstrated that differences in the operational process along with different environmental conditions can lead to different impacts. In the present case groundwater is the potential most sensitive environmental medium despite the well-established consensus in the literature that radon and aerosol emissions may turn-out to be the most relevant environmental aspects of an installation located at this type of region. Most of the ²²⁶Ra content in the ore remains in the leached ore that is deposited with the waste rock. A lack in appropriate prediction of the hydrological balance has been causing unanticipated emissions of liquid effluents into the environment. Chemical treatment of this effluent may be needed. Contamination of groundwater in the short term by the waste ponds is not to be expected but it can be a relevant issue in the long term. As a consequence, careful closure schemes will need to be put in place. Finally, the overall costs with remediation in the Caetité production center are lower than those observed at the Poços de Caldas mining site.     

磷肥厂烘干磨高压静电除尘技术及应用

本文根据高压静电除尘的原理,磷肥厂烘干磨粉尘的特性分析,以及作者本人的工作实践,探讨了高压静电除尘技术在磷肥厂烘干磨粉尘治理中应用的可行性。     

The Worldwide Availability of Phosphate Rock

The US Bureau of Mines has investigated the resource potential of 201 phosphate mines and depositee in 28 market economy countries and 17 mines and deposits in the USSR and China. The 201 mines and deposits contain an estimated 34.2 billiong tonnes (t) of recoverable phosphate rock (at the demonstrated resource level), with Morocco and Western Sahara accounting for 61% (21 billion t) and with the USA accounting for 19% (6.4 billion t). The 17 mines and deposits evaluated in the USSR and China contain approximately 1.5 billion t of potentially recoverable phosphate rock. Potential annual capacity from low-cost, high-grade producing mines in the USA is estimated to decline significantly during the latter half of the next decade, and the US phosphate fertilizer industry will have to obtain phosphate rock by developing new, higher-cost, lower-grade mines or import phosphate rock to satisfy anticipated demand in the next century. Of the world's new production capacity that are likely to be developed over the next decade, slightly over one-third could be produced at an estimated 1981 cost of $40/t or less, and about two-thirds would cost in the $40 to $50 per tonne range (including a 15% rate of return). In comparison, most of the competing phosphate rock from producing mines in Morocco could be produced for less than $40/t.     

Environmental assessment of dehydrated alfalfa production in Spain

Alfalfa is the major forage crop produced in temperate regions worlwide. Although this crop is currently used mainly for producing high-value livestock feed, its application for bioenergy production is a recent focus of interest. Even though it is not mandatory, alfalfa is normally dried in order to improve the quality of the final product. In this study, Life Cycle Assessment (LCA) was used to quantify the environmental impacts linked to alfalfa production in the major cultivation zone in Spain (Ebro Valley), including field activities, dehydration and transport to farms for livestock feeding. In addition, the identification of the most relevant processes contributing to the environmental impact and the potential improvements actions were also defined as objectives. Inventory data were obtained mainly from interviews with farmers complemented with published literature and comments from experts.LCA results were obtained for global warming, acidification, eutrophication, photochemical oxidant formation, land use, non-renewable cumulative energy demand and human, terrestrial and aquatic ecotoxicities. Within the life cycle of alfalfa, the dehydration process, production of phosphate fertilizer, application of nitrogen fertilizers and pesticides, water consumption and final transport to the consumer (by road and ship) were identified as hot spots. Based on these, some improvement measures were proposed and evaluated: (i) reduction of the moisture content of alfalfa and the use of a higher percentage of biomass for combustion in the dehydration process, (ii) no application of nitrogen fertilizer in maintenance years and (iii) use of more efficient trucks for transport. Their implementation would produce significant reduction of eutrophication, global warming, acidification, non-renewable cumulative energy demand and, to a lesser extent, photochemical oxidation formation and human toxicity impacts.