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1.
从溧  王媛 《四川环境》1994,13(1):26-29
本文介绍了在环境监测中,经试验研究,确定的用阳极溶出伏安法,连续分析环境样品中重金属Cu,Pb,Cd的最佳条件,即用悬汞电极做工作电极,用0.1M离氯酸做支持电解质,纯氮除氧。当PH值取2-7,富集电位数-1.1~-1.2V时,不但可连续测定一定浓度范围的重金属Cd,Pb,CU;而且方法灵敏度高,精密良好,线性相关关系可达0.9990,回收率达85-115%,获得了良好的分析效果。  相似文献   

2.
本文检测了83-1除草剂的主要代谢产物—2.4一二氯,6-胺基酚对大鼠、小鼠的LD_(50);同时做了Ames试验。用Horn′s法测定LD_(50)结果为:大鼠雌1000(642~1560)mg/kg,雄1000(554~1810)mg/kg;小鼠雌852(562~1210)mg/kg雄1000(642~1560)mg/kg;Ames试验结果为阳性.  相似文献   

3.
为探讨原油伴生卤水对农作物的影响,进行了种子发芽率试验和田间试验,确定了土壤氯化物含量影响棉花生长的临界值。结果表明,当土壤中氯离子含量大于306.7 mg/kg时,可明显影响棉花的正常生长,使产量明显下降,并污染土壤环境。  相似文献   

4.
本文对UASB-Fe装置处理城市污水进行了中试研究,结果表明,当厌氧HRT3-4小时,进水浓度总CODcr为241.2-402.3mg/l,溶BOD5为80.6-136.8mg/l,SS为170.8-189.8mg/l时,其平均去除率依次为42.1-56.6%,64.0-39.8%和72.9-65.4%。讨论了厌氧HRT,进水浓度,温度等因子对厌氧处理效果的影响情况。浅析了铁填料层在城市污水处理中  相似文献   

5.
本试验采用UASB—接触氧化工艺对沤麻废水的处理进行了研究,系统启动两个月后达到稳定的处理效果,厌氧段进水COD浓度为700mg/1,有机负荷为9.25kgCOD/m3·d,停留时间为24小时,COD去除率可达到89.3%,好氧段接触氧化池的有机负荷为2.IkgCOD/m3·d,处理时间为10小时,整个系统总的COD去除率可达到97%,该工艺是处理高浓度沤麻废水行之有效的方法。  相似文献   

6.
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   

7.
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   

8.
自贡市大气污染的现状研究   总被引:1,自引:0,他引:1  
通过历时4年的自贡市大气污染现状研究结果,大气综合质量指达到GB133095-82大气质量标准的二级以上标准,由于天然气广泛使用,燃料结构发生明显的变化,大气主要污染物为硫化氢及苯并芘,城区最大值分别为0.129μmg/m^3和4.68μg/100m63,郊区分别为0.062mg/m^3和1.12μg/100^3。本研究认为磊气污染属燃气型污染。  相似文献   

9.
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   

10.
富铜米的生产技术为:选择土壤有机质含量高的水稻田,施足基肥,精耕细作;施用7-5kg/ha~22.5kg/ha的硫酸铜和适量的速效氮、磷、钾肥混合后作耙面肥或作早期追肥施入田中;选用良种,栽插适龄壮秧,合理密植,进行科学肥水管理,防治病虫害及适时收割、加工。本技术简便易行、实用性强,可使稻米富铜、优质、高产。用本技术生产的稻米比用常规方法生产的稻米的含铜量提高了1倍~2倍富铜米的生产技术  相似文献   

11.
To understand a state's incentives to invest in conflict or cooperation over their international rivers, this paper argues that it is necessary to appreciate the relationships a river can create and the national security threat riparians may confront. Rivers impose interdependent and vulnerable relationships, which can compromise a state's ability to respond effectively to floods and droughts, meet its domestic food and energy needs, dredge the river, maintain its drainage systems, and allocate its domestic water budget. The inability to accomplish these tasks can contribute to social, economic, and political losses that may threaten a state's territorial integrity. Regardless of whether a state is upstream or downstream, from these relationships it acquires leverage to manipulate the interdependence and vulnerability to inflict losses on its riparian neighbour. This argument challenges several assumptions within the existing literature, including the belief that a shortage of freshwater is the initial force producing a national security threat and that an upstream–downstream river bequeaths all advantages on the upstream state and leaves the downstream state purely dependent. As the paper shows, riparians confront a more complex relationship than captured by the existing literature.  相似文献   

12.
Reducing greenhouse gases in the atmosphere is becoming a pressing issue for the global community. Afforestation and reforestation are promoted worldwide as an effective means of sequestering carbon. For its national interest and global concerns, China has made great efforts to protect its existing forests and develop programs of afforestation and reforestation. Based on two surveys recently conducted in Liping County, Guizhou province, this paper investigates the economic changes associated with the implementation of the "Grain For Green" policy. Based on the analytical framework of benefit cost analysis, this paper concludes that the implementation of the reforestation of sloping agricultural land policy would not be possible if there were no government subsidies for the peasants. The short term economic returns of land and labour from forestation are substantially lower than those generated from grain or cash crop production on the steep slope lands. The government subsidies provide great economic incentives for peasants to take part in the project. The subsidies in fact have elevated peasant income in rural Liping. The estimated potential economic returns of plantations over the long run indicate that the removal of the government financial subsidies would not create an economic crisis for the peasants if the current market conditions continue.  相似文献   

13.
This study employed a mixed-methods design to examine the relationship between nature experience type (e.g., direct and indirect) and learning outcomes (e.g., environmental knowledge, attitudes, and behavior) associated with an environmental education, international immersion program for adolescents. Longitudinal data from 108 participant and 49 comparison group members were analyzed to test the study’s hypotheses. Additionally, qualitative data were analyzed using grounded theory methodology to assess participants’ perceptions of these processes. The findings indicate that environmental knowledge increased more than environmental attitudes during the indirect portion of the program (i.e., preparatory program) whereas the direct portion (i.e., international workshop) produced similar levels of knowledge and attitude growth. Further, while attitudes were more strongly associated with behavior during the indirect component of the program, the strength of the relationships between attitudes and behavior, and knowledge and behavior were similar during the direct portion of the experience. A synthesis of the findings suggests that the program’s direct experiences catalyzed environmental knowledge into a stronger motivating force than it had been during the indirect experiences. The qualitative findings also provide insights into the characteristics of direct experiences. These findings offer important insights for both theory and practice related to the use of direct and indirect nature experiences to develop environmental knowledge, attitude, and behaviors.  相似文献   

14.
研究了青岛崂山野生草本药用花卉的生物学特征、生态分布、观赏及药用价值 ,讨论了它们的开发利用途径 ,以期为青岛崂山野生草本药用花卉的合理开发和持续利用提供可靠、详实的依据。  相似文献   

15.
The levels of iron (Fe) and zinc (Zn) were quantitatively determined in soil and water samples as well as in staple food cultivars in Itakpe, Nigeria's major iron mining town. The survey was conducted to establish a baseline pollution index for Fe and Zn in the Itakpe environment and to evaluate the role of foods as an exogenous source of these metals among the inhabitants. Exceedingly high levels of both metals characterized the staple food cultivars in the town.  相似文献   

16.
This article examines the history and character of the water supply in Trinidad and Tobago and the nature of problems associated with the procurement of water by Trinidadians. The article reports on case studies of two rural communities in which women have taken the lead to solve water problems. It reflects on the importance of small‐scale, community‐managed water systems for the possibility of achieving water democracy.  相似文献   

17.
洞庭湖区野生动植物资源十分丰富,生产潜力大.但由于盲目开发、泥沙淤积和环境污染,导致野生动植物生境被破坏,生物生产力下降,并造成物种灭绝.因此,必须加强执法力度,加大投入,保护湖区野生动植物资源的多样性,采取强有力措施对洞庭湖湿地生态环境进行综合整治,建立科学合理的生物利用模式和具有湖区特色的产业结构,对洞庭湖区野生动植物资源进行可持续开发利用.  相似文献   

18.
Zinc- and lead-containing wastes are often mixed with construction and demolition wastes in many factories, generating abundant of heavy metal-enriched hazardous waste. In the present study, a novel integrated process of air classification, alkaline leaching, and water washing dechlorination was proposed for the efficient recycling of Zinc (Zn) resources. The first air classification process was realized via venturi tube, wherein the content of Zn could increase by 20 wt.%. After that, the product underwent an alkaline leaching process. Results showed that Zn recovery rate increased with fine particle sizes, and a 65% recovery rate was obtained under the following conditions of 5 mol/L NaOH, liquid/solid 10:1, and leaching time 1 h. Finally, water washing associated with microwave and ultrasonic treatments could remove over 85% of Cl and other water-soluble salts. All the results indicated that the integrated method had an excellent recovery rate for Zn resources from construction and demolition wastes.  相似文献   

19.
Aibi Lake in north Xinjiang is a typical lake of the arid area, but with a peculiar wetland–arid area ecosystem. Due to the climate becoming drier and the disturbance of human activities, the eco-environment of Aibi Lake catchment has degraded. It was found in our study that there were spatial–temporal changes of vegetation cover, plant species, and soil physical and chemical properties in the catchment. In the upper section of alluvial–fluvial plains, the desertified steppe of Stipa and Artemisia spp. is developed with vegetation cover of some 50%. Haloxylon ammodendron desert occupies the lower section with vegetation cover of some 60%. In these regions with an intensive human disturbance, vegetation has degraded into herb vegetation of annual plant complexes. On the margins of the alluvial–fluvial fans, the lakeshore, and the surrounding regions where the river mouths join the lake, different azonal vegetation—Phragmites communis marsh, Phragmites communis meadow, and Tamarix shrubs—have developed with a vegetation cover of some 80%. On heavier, salinized land, succulent halophyte desert vegetation dominated by Halocnemum strobilaceum has formed with a fractional canopy cover of 10–15%. Haloxylon persicum, Aristida pennata, and other species with a vegetation cover of 30–50% grow in the sand desert zone on the periphery in the lake. In contrast with the 1950s, the vegetation cover around the lakebed and at the river deltas has slightly increased; however, the vegetation cover around the periphery of the lake has decreased and the plant species have still degraded. The surface soils on the windward area and the dried lakebed that have lost vegetation protection have become coarser, whereas the land on the leeward side of the lake has accumulated fine particles. In contrast with the 1980s, soil organic matter has declined markedly. The analyses of climatic data show that the number of days of drifting dust in Jinghe County and Bole City increased in the last 20 years. In the investigation, we found that intensively developed land, the bare lakebed, and abandoned cultivated land provided a great deal of material for drifting dust. In conclusion, we consider the eco-environmental degradation resulting from the inappropriate human activities and put forward recommendations for land-use adjustment and dust control.  相似文献   

20.
马铃薯糖苷生物碱的生物学作用及开发利用   总被引:12,自引:0,他引:12  
本文根据作者近年的研究成果及国外研究动态,简要介绍了马铃薯糖苷生物碱的种类,结构,含量及在植株中的分布;重点论述了糖苷生物碱的毒性,毒理及对块茎食用、饲用和加工品质的影响,糖苷生物碱与马铃薯植株自身的抗病,抗虫性及其抗病虫育种的关系,以及糖苷生物碱在医药学中的应用价值,为马铃薯的综合开发利用指出了新途径。  相似文献   

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