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1.
会理污灌区重金属污染的调查,评价及防治对策   总被引:4,自引:0,他引:4  
王春  杨德芬 《四川环境》1998,17(3):41-46
本文调查、评价了会理县锌矿污灌区内水、土、作物的重金属污染状况。调查结果表明:污灌区内土壤、作物重金属污染严重,尤以镉污染突出。作物中镉含量与距污染源距离呈负相关(r=-0.995)。镉在水稻植株各部位的分布,以根系含镉量最高,茎叶次之,谷粒最少。评价结果表明农灌水的污染程度不大,土壤中Cd、Zn、Pb污染是土壤污染的主要表现,水稻的污染较玉米更为严重。Cd已对人体健康构成潜在危害。本文还针对污染区的重金属污染提出了相应的防治措施  相似文献   

2.
本文讨论了工业排放含Cu,Pb废水对永丰乡南效村蔬菜地的影响。结果表明:调查地土壤已遭较严重的Cu,Pb合污染。土地壤Cu含量为77.56-1682mg/kg,为对照点的1.6-34倍,所采16个土样中有15个点的土壤Cu含量超过国家标准。土壤中Pb含量为40.5-416mg/kg,为对照点的1.1-11倍。生长于其上的蔬菜已不同程度的受到Cu,Pb的污染。  相似文献   

3.
离子选择电极法测定水和废水中总氰化物   总被引:2,自引:0,他引:2  
商文新 《四川环境》1995,14(4):23-26
本文在查阅国内外文献的基础上,对氰化物测定中的前处理方法和干扰消除进行了简要综述。同时对氰离子选择电极法测定氰化物进行了研究,测定的pH应控制为12-13,检测下限为0.03mg/l。并用离子交换的方法分离阳离子,以PbCO3为沉淀剂分离S^2-后,对废水样进行分析,效果良好。  相似文献   

4.
陈玉谷  李艳 《四川环境》1993,12(4):17-21
本试验采中中温UASB反应器处理酒精废液,通过启动、运行、颗粒污泥不同时期形成过程的探索,成功地培养出了颗粒污泥,取得了有机负荷高达13-22gCOD/l.d,HRT15.6-22.3hr,CODcr去除率达83.9-92.2%,沼气产气率5.1-8.71/l.d,CH4含量55-72%的良好效果。  相似文献   

5.
示差脉冲阳极溶出伏安法测定中药川附子痕量铅镉   总被引:6,自引:2,他引:4  
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%。  相似文献   

6.
用示波极谱法对酚类化合物进行分析,方法的线性范围在3.0×10 ̄(-5)~8.0×10 ̄(-3)mg/L之间,最低检出限为6.0×10 ̄(-6)mg/L,浓度为0.26×10 ̄(-2)~0.52mg/L时的相对标准偏差为1.8%~4.0%,浓度为0.3×10 ̄(-2)~0.51mg/L时的回收率为95.0%~102.1%,其结果与4-氨基胺替比林分光光度法相一致。  相似文献   

7.
气候试验箱的加湿方法   总被引:1,自引:1,他引:0  
陈谋义 《环境技术》1999,17(6):18-23
1 气候试验箱常用的几种加湿方法。1.1 蒸汽加湿法:分电热管或电极加湿及高压蒸汽喷雾加湿;1.2 水喷雾加湿法:分超声波式、离心喷雾式和水泵喷淋式;1.3 表面蒸发加湿法,用浅水盘加湿各种加湿方法的特性见表1。表1 加湿特性表表1(续)2 加湿方法的比较。2.1 蒸汽加湿法:利用气候试验箱外的热源,如电热管、电极对水槽内的水进行加热而产生蒸汽,然后蒸汽进入气候箱中,使箱内的空气加湿。箱中的湿空气在未加湿前焓值为i=1.005t+d(2500+1.84t)(1)式中:i———为1kg干空气的湿空…  相似文献   

8.
采用新型载体的好氧流化床的动力学研究   总被引:1,自引:0,他引:1  
本文以稀释的味精废水为基质,对采用新型载体LSAR的好氧生物流化床进行动力学研究,求得动力学参数分别为γmax=8.81(gCOD/gvs.d),Ks=0289(gCOD/L),Kd=0.046d^-1,Y=0.16(gvs/gCOD)。其值基本处于文献的报导之内,说明以LSAR为载体的好氧微生物膜具有较好的活性,LSAR作为好氧流化床载体是可行的。  相似文献   

9.
吕广顺 《青海环境》1999,9(1):39-40,46
用EDTA法测定Ca^2+时,对Fe^3+,Cu^2+,Pb^2+,Mn^2+的干扰进行了试验,分别得出了最小干扰浓度,不同的干扰离子和浓度。采用不同的方法消除,效果良好。  相似文献   

10.
内江市磷肥厂磷矿石,磷肥样品中天然铀,镭—226含量分析   总被引:1,自引:0,他引:1  
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。  相似文献   

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In the latter half of the 20th century, native pine woodlands in Scotland were restricted to small remnant areas within which there was little regeneration. These woodlands are important from a conservation perspective and are habitat for numerous species of conservation concern. Recent developments have seen a large increase in interest in woodland restoration and a dramatic increase in regeneration and woodland spread. The proximate factor enabling this regeneration is a reduction in grazing pressure from sheep and, particularly, deer. However, this has only been possible as a result of a complex interplay between ecological, political and socio-economic factors. We are currently seeing the decline of land management practices instituted 150-200 years ago, changes in land ownership patterns, cultural revival, and changes in societal perceptions of the Scottish landscape. These all feed into the current move to return large areas of the Scottish Highlands to tree cover. I emphasize the need to consider restoration in a multidisciplinary framework which accounts not just for the ecology involved but also the historical and cultural context.  相似文献   

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3月26日至3月28日,备受关注的2003年度中国石油集团公司安全生产环境保护职业健康工作会议在青岛召开。 会议期间王海森主任做了题为“与时俱进,开拓创新,推进安全环境健康工作再上新水平”的报告,指出此次会议的主要任务是:总结回顾过去三年安全生产,环境保护和职业健康工作,分析形势,安排部署2003年工作,推进安全环境健康工作再上新水平。回顾三年的成绩,主要体现在:安全环保健康目标和责任制不断落实;安全环保健康规章制度逐步完善;安全环保机构得到加强和充实;健康安全环境管理体系全面推进;建设项目环境管理规范进行;安全环保科技创新…  相似文献   

16.
The Truckee River heads in the Sierra Nevada at Lake Tahoe, and terminates in Pyramid Lake. During the 1969 water year, flow about 9 miles upstream from the mouth (974,000 acre-ft) was almost four times the long-term average, due mainly to heavy winter rains and spring snowmelt. A short period of low-altitude rainfall produced the highest concentrations of suspended sediment, whereas a much longer subsequent period of snowmelt yielded a much greater total quantity of material. The upper 90 percent of the basin yielded about 260 acre-feet (630,000 tons) of sediment at the Nixon gage, whereas an estimated 2,800 acre-feet (6.8 million tons) was contributed by erosion of about 200 acres of river bank below the gage. Solute content at the gage ranged from 80 to 450 mg/l, dominated by calcium, sodium, and bicarbonate, plus silica in the most dilute snowmelt and chloride in the most concentrated low flows. Solute load totaled about 130,000 tons, of which the principal constituents in Pyramid Lake-sodium plus equivalent bicarbonate and chloride-amounted to almost 40,000 tons. The total solute load during a year of average flow may be 45,000-55,000 tons, including 18,000-22,000 tons of principal lake constituents.  相似文献   

17.
ABSTRACT: The relationship between chlorophyll u, total phosphorus, secchi disk depth, and trophic state were examined using data on U.S. lakes collected by U.S. EPA's National Eutrophication Survey. By comparing predicted secchi disk depths with observed summer secchi disk depths in 757 lakes, it was determined that in many lakes non-chlorophyll related light attenuation is important in controlling the amount of chlorophyll u produced per unit of total phosphorus. Ranking of 44 lakes by 18 different trophic state measurements and single and multivariable indices were compared with rankings provided by mean summer ambient total phosphorus and chlorophyll u. The trophic state measurements and indices were much more successful in ranking the lakes against total phosphorus than chlorophyll u, indicating that there are differences in the relative trophic rankings of many of the lakes depending upon whether primary nutrients or biological manifestations are used as the ranking mechanism. If the manifestations of nutrients rather than their absolute levels are the primary criteria for beneficial use of lakes, the use of many of the commonly employed trophic state measurements, which assume or imply that there is a constant relationship between total phosphorus or secchi disk and chlorophyll, can lead to erroneous conclusions and unnecessary costly management controls. Secchi disk measurements may be more useful as a predictor of ambient lake total phosphorus concentrations than of chlorophyll.  相似文献   

18.
Iron oxides are important components influencing the adsorption of various inorganic and organic compounds in soils and sediments. In this study the adsorption on iron oxides of nonionic and ionic pesticides was determined as a function of solution pH, ionic strength, and pesticide concentration. The investigated iron oxides included two-line ferrihydrite, goethite, and lepidocrocite. Selected pesticides comprised atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine), isoproturon [3-(4-isopropylphenyl)-1,1-dimethylurea)], mecoprop [(RS)-2-(4-chloro-2-methylphenoxy)propionic acid], 2,4-D (2,4-dichlorophenoxyacetic acid), and bentazone [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide]. The adsorption of the nonionic pesticides (atrazine and isoproturon) was insignificant, whereas the adsorption of the acidic pesticides (mecoprop, 2,4-D, and bentazone) was significant on all investigated iron oxides. The adsorption capacity increased with decreasing pH, with maximum adsorption reached close to the pKa values. The addition of CaCl2 in concentrations from 0.0025 to 0.01 M caused the adsorption capacity to diminish. The adsorption of bentazone was significantly lower than the adsorption of mecoprop and 2,4-D, illustrating the importance of a carboxyl group in the pesticide structure. The adsorption capacity on the iron oxides increased in the order: lepidocrocite < goethite < two-line ferrihydrite. The maximum adsorption capacities of meco-prop and 2,4-D on goethite were found to be equivalent to the site density of singly coordinated hydroxyl groups on the faces of the dominant (110) form, suggesting that singly coordinated hydroxyl groups are responsible for adsorption. Differences in adsorption capacities between iron oxides can be explained by differences in the surface site density of singly coordinated hydroxyl groups. The maximum measured adsorption capacity of mecoprop on two-line ferrihydrite was equivalent to 0.2 mol/mol Fe.  相似文献   

19.
Atrazine (6-chloro-N2-ethyl-N4-isopropyl-1,3,5-triazine-2,4-diamine) and metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide] have been found with increasing occurrence in rivers and streams. Their continued use will require changes in agricultural practices. We compared water quality from four crop-tillage treatments: (i) conventional moldboard plow (MB), (ii) MB with ryegrass (Lolium multiflorum Lam.) intercrop (IC), (iii) soil saver (SS), and (iv) SS + IC; and two drainage control treatments, drained (D) and controlled drainage-subirrigation (CDS). Atrazine (1.1 kg a.i. ha-1), metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazine-5(4H)-one] (0.5 kg a.i. ha-1), and metolachlor (1.68 kg a.i. ha-1) were applied preemergence in a band over seeded corn (Zea mays L.) rows. Herbicide concentration and losses were monitored from 1992 to spring 1995. Annual herbicide losses ranged from < 0.3 to 2.7% of application. Crop-tillage treatment influenced herbicide loss in 1992 but not in 1993 or 1994, whereas CDS affected partitioning of losses in most years. In 1992, SS + IC reduced herbicide loss in tile drains and surface runoff by 46 to 49% compared with MB. The intercrop reduced surface runoff, which reduced herbicide transport. Controlled drainage-subirrigation increased herbicide loss in surface runoff but decreased loss through tile drainage so that total herbicide loss did not differ between drainage treatments. Desethyl atrazine [6-chloro-N-(1-methylethyl)-1,3,5-triazine-2,4-diamine] comprised 7 to 39% of the total triazine loss.  相似文献   

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