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1.
Evidence for photochemically induced interactions in Ekofisk crude oil as a thin film on top of a water surface has been obtained by isotopic labelling experiments and field desorbtion mass spectrometry. The interaction behaviour to the high molecular weight resin/asphaltene material has been discussed by invoking the concept of molecular assemblies like micelles and vesicles. This latter chromophoric material has also been shown to have an appreciable sensitizing effect, resulting in a substantial transformation of carbon 14 radiolabelled species, including straight chain n-alkanes.Isotopic studies do not provide evidence for interactions in Ekofisk crude oil constituents kept in darkness, where only a very slow transformation/degradation of oil components has been observed.The implication of these findings has been discussed.  相似文献   

2.
It is gratifying to report that 1975-1976 has been another year of increased activity for the Air Pollution Control Association, and various indicators are positive compared to previous years. Membership has increased, attendance at meetings has increased, we have a substantial surplus to report, there is increased activity in membership interest and in our overall activity. Public affairs involvement has increased somewhat, as have our international activities. Local sections and technical committees have expanded their scope of productive involvement. Clearly, APCA has had a successful and productive year.  相似文献   

3.
Extractive reserves constitute an innovative approach to match conservation and development objectives, which were originally envisaged as part of a land struggle by forest dwellers in Brazil. In spite of the idea's popularity and the attempts to apply the concept to different tropical regions, there has been little analysis of the combined conservation and development performance of extractive reserve programs. We present a detailed analysis of deforestation and demographic and socioeconomic changes in Alto Juruá, the first extractive reserve created in Brazil in 1990. Forest cover has remained fairly stable. Population has declined slightly, with some internal displacements. The cash economy base has shifted from the original rubber production to a diversified portfolio of agriculture and livestock, and there has been a dramatic rise in nonagrarian income. We conclude that the Reserve represents a very dynamic setting with positive conservation and development outcomes during its first decade.  相似文献   

4.
Assuming that settling takes place in two zones (a constant rate zone and a variable rate zone), a model using four parameters accounting for the nature of the water-suspension system has been proposed for describing batch sedimentation processes. The sludge volume index (SVI) has been expressed in terms of these parameters. Some disadvantages of the SVI application as a design parameter have been pointed out, and it has been shown that a relationship between zone settling velocity and sludge concentration is more consistent for describing the settling behavior and for design of settling tanks. The permissible overflow rate has been related to the technological parameters of secondary settling tank by simple working equations. The graphical representations of these equations could be used to optimize the design and operation of secondary settling tanks.  相似文献   

5.
Environmental Science and Pollution Research - Nanotechnology has opened up a plethora of opportunities and has acquired extreme importance in a myriad of fields to produce enhanced materials....  相似文献   

6.
采用天然石灰石做脱硫剂,在固定床上进行硫化氢高温脱除的试验研究,考察了脱硫剂粒径、反应温度、气速及高温煤气中H2对石灰石脱硫性能的影响,同时还用热重分析(TG)、扫描电镜(SEM)、X-射线衍射(XRD)等测试手段对脱硫剂的物相组成和结构等进行了表征。结果表明,脱硫剂的粒径对脱硫效果的影响很大,0.38~0.83 mm的石灰石脱硫效果最佳;温度对脱硫效果的影响比较复杂,最佳的操作温度为850℃;气速对脱硫效果的影响较明显,脱硫剂的穿透时间随气速的减小而加长;H2对脱硫过程起阻碍作用,气速越小,这种阻碍作用越明显。  相似文献   

7.
Environmental Science and Pollution Research - Inevitably increase in plastic demand has resulted in an overgrowing production on a global scale. The utilization of plastics has been applied to a...  相似文献   

8.
Jiang Y  Chen Y  Younos T  Huang H  He J 《Ambio》2010,39(7):467-475
Since China has the largest population in the world, the available water resources per capita in China are very limited. With the rapid economic development that is currently occurring, the shortage of water resources at the national level has become extremely critical. How to solve the problems due to water scarcity and water pollution has received increasing attention from the Chinese government and various communities. In order to provide a sustainable development environment for 1.6 billion people in the future, the whole country has started to reform urban water resources management systems in terms of related policies, regulations, methodologies, and technologies focusing on improving the efficiency and effectiveness in water use. Urban water quota management has now become a core strategy in developing a water resources governance model for water demand management aiming at establishing a water-saving society. This paper introduces the main stages and the processes of implementing water quota management in China, analyzes the basic principles, and expounds the elements, information foundation, core module and operational model of the urban water quota management system. It has been demonstrated that urban water quota management has made some remarkable contribution not only in transforming the pattern of water mode and strengthening water management enforcement but also in integrating various management methods in saving water and preventing pollution.  相似文献   

9.
Environmental Science and Pollution Research - Obesity is a term that has recently been referred to describe a condition in which a person has become a diseased vessel. Obesity’s internal...  相似文献   

10.
Environmental Science and Pollution Research - Hydroxyurea (HDU), a class of antineoplastic drugs, has a powerful efficacy in the treatment of several types of malignancies. However, it has...  相似文献   

11.
A coupled solar photo-Fenton (chemical) and biological treatment has been used to remove biorecalcitrant diuron (42 mg l(-1)) and linuron (75 mg l(-1)) herbicides from water at pilot plant scale. The chemical process has been carried out in a 82 l solar pilot plant made up by four compound parabolic collector units, and it was followed by a biological treatment performed in a 40 l sequencing batch reactor. Two Fe(II) doses (2 and 5 mg l(-1)) and sequential additions of H2O2 (20 mg l(-1)) have been used to chemically degrade the initially polluted effluent. Next, biodegradability at different oxidation states has been assessed by means of BOD/COD ratio. A reagent dose of Fe=5 mg l(-1) and H2O2=100 mg l(-1) has been required to obtain a biodegradable effluent after 100 min of irradiation time. Finally, the organic content of the photo-treated solution has been completely assimilated by a biomass consortium in the sequencing batch reactor using a total suspended solids concentration of 0.2 g l(-1) and a hydraulic retention time of 24h. Comparison between the data obtained at pilot plant scale (specially the one corresponding to the chemical step) and previously published data from a similar system performing at laboratory scale, has been carried out.  相似文献   

12.

Background and purpose  

Pakistan, during the last decade, has seen an extensive escalation in population growth, urbanization, and industrialization, together with a great increase in motorization and energy use. As a result, a substantial rise has taken place in the types and number of emission sources of various air pollutants. However, due to the lack of air quality management capabilities, the country is suffering from deterioration of air quality. Evidence from various governmental organizations and international bodies has indicated that air pollution is a significant risk to the environment, quality of life, and health of the population. The Government has taken positive steps toward air quality management in the form of the Pakistan Clean Air Program and has recently established a small number of continuous monitoring stations. However, ambient air quality standards have not yet been established. This paper reviews the data being available on the criteria air pollutants: particulate matter (PM), sulfur dioxide, ozone, carbon monoxide, nitrogen dioxide, and lead.  相似文献   

13.
固硫型煤的生产技术和使用效果   总被引:1,自引:0,他引:1  
针对链式炉炉内脱硫,设计了固硫型煤生产线,通过测试、试验、生产和实际使用,使固硫型煤满足脱硫要求,同时,节能效果也较明显。另外,对固硫剂、粘结剂的选用和配比作了介绍。  相似文献   

14.
In the past, many species of pine have been severely damaged by acute forms of air pollution associated with ore smelting. More recently, damage to ponderosa pine in the state of Washington has been associated with atmospheric fluoride, and this species in particular has also suffered smog damage in southern California. In the East, white pine has been declining in the vicinity of certain soft-coal-burning power plants, and in one case downwind from an oil-burning power plant: also, throughout the East, an atmospheric oxidant of unknown source has caused a type of needle blight on white pine. Trash burners and city dump combustion have led to the hilling of certain pine species, leaving other intermixed pine species unharmed. Localized damage to white pine from automobile exhaust has been observed. Differences in the susceptibility of neighboring trees of the same species to a given air pollutant have been observed repeatedly.  相似文献   

15.
Environmental Science and Pollution Research - Cold plasma has been a potent energy-efficient and eco-friendly advanced oxidation technology which has gained attention in recent decades as a...  相似文献   

16.
采用弹性填料微孔曝气生物预处理方法净化受污染的某饮用水源,探讨了水源水环境中NH4+-N变化对生物预处理除NH4+-N作用效果的影响。结果表明,水源水环境中的NH4+-N对生物预处理工艺除NH4+-N有一定的影响作用。  相似文献   

17.
Environmental Science and Pollution Research - In recent years, as environmental degradation has become more and more serious, the Chinese government has formulated a series of environmental...  相似文献   

18.
通过用密封法与回流法对焦化厂废水CODCr的测定实验比较表明,密封法与回流法有很好的相关性。密封法应用于焦化废水的CODCr测定中,具有可进行批量分析、试剂和水电消耗少等优点。  相似文献   

19.
Greening China Naturally   总被引:2,自引:0,他引:2  
Cao S  Sun G  Zhang Z  Chen L  Feng Q  Fu B  McNulty S  Shankman D  Tang J  Wang Y  Wei X 《Ambio》2011,40(7):828-831
China leads the world in afforestation, and is one of the few countries whose forested area is increasing. However, this massive "greening" effort has been less effective than expected; afforestation has sometimes produced unintended environmental, ecological, and socioeconomic consequences, and has failed to achieve the desired ecological benefits. Where afforestation has succeeded, the approach was tailored to local environmental conditions. Using the right plant species or species composition for the site and considering alternatives such as grassland restoration have been important success factors. To expand this success, government policy should shift from a forest-based approach to a results-based approach. In addition, long-term monitoring must be implemented to provide the data needed to develop a cost-effective, scientifically informed restoration policy.  相似文献   

20.
Environmental Science and Pollution Research - Progressive industrialization in recent decades has contributed to the increase of metal levels in the environment, which has a dangerous impact on...  相似文献   

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