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1.
Toluene diisocyanate (TDI) is an important industrial raw material that is widely used in manufacture of polyurethane coating and insulating materials. TDI is universally considered to be an industrial allergen, which can be introduced into human bodies b…  相似文献   

2.
A successful piece of applied research will not only influence the related problem perception within the scientific community, but also lead to much better understanding of a complex challenge, including the delivery of solutions. Ideally it may contribute significantly to reducing possible risk situations for people and/or the natural environment. In short, a successful study will have a broader impact beyond the sphere of science. Planning, timing, funding, networking, communication, and interdisciplinarity are identified as key aspects for a successful project and are being examined in their scope and boundary conditions, while not neglecting the particular role of local and regional people and authorities.Defining what makes a successful environmental geochemical study is clearly based upon experience and evidence found, and not upon any particular theoretical concept. Here, experience is drawn from the outcome of many projects and specifically first-hand from the complex ARSENEX project in Minas Gerais, Brazil. Against the backdrop of both perceived and real arsenic contamination of environmental compartments, including local people, all subsequent project steps and proposals were set up using a three-prong approach that sought to a) understand the processes, b) educate and inform the public and all other stakeholders and c) remediate the situation.  相似文献   

3.
Antimony has long been recognized as a non-essential, potentially toxic element. It has recently been suggested, on the basis of measured elemental profiles in peat bogs, that natural levels of Sb in the environment have been overestimated by a factor of 10 and that anthropogenic Sb deposition from the atmosphere has closely followed that of Pb. The implication is that the health effects of environmental Sb may have been seriously underestimated. To examine these propositions, we have compared new data for Sb and Pb in dated cores from four Scottish ombrotrophic peat bogs, Carsegowan Moss, Flanders Moss, Red Moss of Balerno and Turclossie Moss, in southwest, west-central, east-central and northeast Scotland, respectively. Dried peat sections, 1 to 2 cm thick, were subjected to microwave-assisted digestion in nitric/hydrofluoric acid and subsequently analyzed for a range of elements (including Sb, Pb, and the conservative elements Sc, Ti) and Pb isotopic composition by ICP-OES and ICP-MS as appropriate. Three certified reference materials, including NIMT/UOE/FM/001 Peat, were used for quality control purposes. Radiometric dating of upper and lower sections of the cores was carried out using gamma spectrometry for ^21-Pb and accelerator mass spectrometry for ^14C, respectively Some 2000 years ago, in Roman times, both Sb and Pb were clearly elevated in Scottish peat but typically at concentrations below 0.1 mg/kg and 5 mg/kg, respectively, with an average anthropogenic Sb/Pb ratio of-0.01.  相似文献   

4.
He  Ling-Yun  Zhang  Hong-Zhen 《Natural Hazards》2021,105(1):611-630
Natural Hazards - Existing researches about environment regulation mainly focus on its effect on enterprises’ production decision-making behavior but neglects the effect on the individual and...  相似文献   

5.
Groundwater of Egypt: “an environmental overview”   总被引:1,自引:0,他引:1  
Although Egypt has the great Nile River, which is the main supply of water, Egypt’s water is limited to 55.5 billion m3 per annum. Owing to the rapid growth of the population and the increasing consumption of water in agriculture, industry, domestic use, etc., it is expected that Egypt will rely to some extent on groundwater to develop the new projects such as Tushka in Upper Egypt and East Oweinat. Issues related to groundwater in Egypt are identified with the common geological features associated with formation of the aquifers and demonstrating the location of the main resources of groundwater, followed by the main objective of this paper, which is addressing the environmental issues related to groundwater in Egypt. Several studies have been reviewed and personal communication made with the authorities to introduce this work and provide an overview of the groundwater quality problems in Egypt with examples from different parts of the country.  相似文献   

6.
We usually conduct environmental investigation through sample study. Therefore, it is essential that samples should be representative, at all time, and of the object be studied. However, the issues of sample representativeness and sampling errors are often neglected by investigators. Based on modem geo-statistics and sampling theory, this paper addresses these issues in more detail and presents a case study related to environmental risk assessment. The issue of sample representativeness can be measured in the following three aspects: (1) whether the sample numbers are large enough to reflect the characteristics of the initial object being studied); (2) whether the sample mass (or sample volume) is large enough to represent the original site (the local segment being sampled); (3) whether assay portion is prepared well enough to depict the initial sample. Sample numbers are dictated by the confidence level, the variance of population and the acceptable estimation error as well as the homogeneity and the spatial continuity of population.  相似文献   

7.
8.
Got green? addressing environmental justice in park provision   总被引:3,自引:0,他引:3  
We present a pragmatic approach to assist planners in addressing racial inequities in park access. Utilizing the Los Angeles metropolitan region as an example, we used Thiessen polygons to delineate a service area for each park, and described potential park congestion or ‘pressure’ in each park service area. Results show that Latinos, African-Americans, and low-income groups in general were likely to live close to parks with higher potential park congestion. On the other hand, predominantly White, high-income areas were typically located close to parks with lower potential park congestion levels. The park service area analysis presented here facilitates the identification of areas with greater park need and provides a pragmatic way to redress existing disparities in park access. Built into a set of web-based decision support tools, the approach fosters greater community participation and empowers local stakeholders in the process of park provision.  相似文献   

9.
In this article, we examine the relations between global value chain governance and environmental upgrading in maritime shipping. Drawing from interviews with global shipping companies and major buyers of shipping services (cargo-owners), we reveal the key issues and challenges faced in improving the environmental performance of maritime transportation. Contributing to the Global Value Chain (GVC) literature, we compare and analyze the influence of three main external drivers on environmental upgrading in the tanker, bulk and container shipping segments: regulation, cooperation and buyer demands. Our findings suggest that environmental upgrading is more likely to occur when global value chains are characterized by unipolar governance and where the lead firms are consumer-facing companies with reputational risks. Furthermore, environmental upgrading in shipping is not likely to materialize without clear and enforceable global regulation and stronger alignment between regulation and voluntary sustainability initiatives.  相似文献   

10.
Because of the high degree of automation in the coal mining industry in the Ruhr area, Germany, about 1 metric ton of crushed rock/colliery spoil is brought to the surface for every metric ton of coal. Most of the colliery spoil disposed of must be dumped. These colliery spoil dumps are anthropogenic geological sediment bodies, which have a characteristic facies resulting from geological, technical, and economical factors connected with the formation of the dumps. The relation between the facies of the dumps and these factors, for example, is examplified with the pyrite content within the colliery spoil. Pyrite content within the dumps is dependent both on the conditions during sedimentation and (early) diagenesis and the techniques used for mining and processing. Thus, this geologic-technical facies of the dumps controls the weathering processes on and in dumps. These humaninduced processes are mainly responsible for the environmental impact on soil and groundwater. Oxidation of pyrite as well as alteration of pyrite under anoxic conditions yields dissolution of carbonates, accompanied by gypsum formation, by acid attack and strong acidification takes place.  相似文献   

11.
12.
In aquatic environment, iron redox reaction may occur through a) microbial activity and b) photo-chemistry. Iron chemistry plays a significant role in the health of aquatic ecosystems. For example, Fe^2+ is more mobile than Fe^3+. Iron can be bound to dissolved organic carbon (DOC), and when Fe^2+ is oxidized to Fe^3+ (biotically or abiotically), Fe is precipitated and induce co-precipitation of the DOC. Furthermore, iron is a major nutrient to aquatic organisms. Because Fe^2+ is more bioavailable than Fe^3+, iron redox chemistry can be a controlling factor in biological production, such as algae bloom which can be a public health concern. Experiments have shown that Fe redox reactions, biotically or abiotically, can generate significant Fe isotope fraction among different Fe species. Accordingly, analysis of Fe isotope composition of phytoplanktons can be a valuable tool in studying Fe dynamics in ecosystems. Precise measurement of Fe isotope, however, presents some challenges. Recent advances in mass spectrometry, specifically high resolution MC-ICP-MS, allow measurement of Fe isotopes free of interferences.  相似文献   

13.
Several rivers researched around Taihu Lake in Chinese eastern plain are distributed to the west of the lake. Pollutants of different types from tributaries and inlets flow directly into the main rivers and finally into the lake. They change trace elements of rivers fi'om which we can analyze. Researches about trace elements are helpful for understanding the pollutant characteristics, industrial structure and agricultural cultivation in the area of network rivers in the plain of China. Samples of water column, suspended matter and sediment were collected fi'om the west rivers of Taihu Lake, which represent three typical rivers. Observation in the field and the primary composition analysis showed the Caoqiao River was mainly contaminated by industrial wastewater, the Liangxi River was discharged by domestic sewage and the Dapu River was principally input by farmland runoff. REE concentrations and their normalized curves showed obvious characters for rivers discharged by different sewages. The contents of total REE in water column followed the order of the Caoqiao River, the Dapu River and the Liangxi River fi'om high to low. TREEs in suspended matter and sediments follow the order of the Dapu River 〉 the Caoqiao River 〉 the Liangxi River. REE normalized curves (for Australia shale) suggested that significant diversities were presented in water column, suspended matter and sediments, i.e., heavy REE enrichment in water, middle REE enrichment in suspended matter, and smooth curves for sediments. But the heavy pollution resulted in several anomalous curves in the same rivers. Some element ratios were selected as indices for polluted rivers based on their geochemical properties and diversities between rivers. The results displayed the discriminative indices for water column, suspended matter and sediment. The effective indices were Pb/Fe, Cr/Fe, Ni/Fe, Pb/Ni, Zn/Ni for water column, Cu/Al, Cu/Fe, Zn/Fe, K/Ca, K/Na, Pb/Co, Zn/Co for suspend matter and Pb/Fe, K/Ca, Ca/Mg, Zn/Ni for sediment, respectively. In general, rivers mainly discharged by industrial sewage have high ratios of Pb/Ni, K/Ca, are enriched in the middle REE and have positive Gd anomaly. The domestic sewage flowing into rivers reveals high ratios of Zn/Ni, Pb/Fe, and is enriched in the heavy REE, and has the positive Eu anomaly. If runoff of farmland enters into the rivers, it will have high ratios of Ca/Mg, K/Na, high lanthanum, and show the smooth normalized curves of REE.  相似文献   

14.
Ecotourism environmental impact assessment is a traveling activity relevant influence prediction and appraisal. And the setting-up of the index system is very important to implement the appraisal of environmental impact of ecological travel. According to …  相似文献   

15.
In the paper the procedure for and results of a test study of a few persistent organic pollutants - polycyclic aromatic hydrocarbon (PAH), polychlorinated biphenyls (PCB) and hexachlorobenzene (HCB) emission from the open burning of different types of wastes (domestic wastes, agricultural debris, landscape cleating debris, etc.) are discussed. The open burning of agricultural debris and landscape-clearing debris is widely applied in rural areas and small towns and in allotment gardens for the recovery of that part of wastes that can not be utilized for compost preparation. This process is most typical during the autumn season and to a lesser degree during spring. Burning occurs usually in bon fires. Burning modes differ depending on the volume of material burnt, the waste moisture content, the weather conditions, etc. During this process part of domestic wastes (polluted wood, paper, chipboard, films, plastics, etc.) are burned also. Investigations included the collection and preparation of combustible material, the simulation of open burning processes, particulate and gas emission sampling, chemical analysis of sample and data processing. Sampling procedures and sample preparation were agreeable to the emission sampling standards. The aerosol and vapour phases of POPs were collected by ordinary sampling train with pumping of waste gases through filter and solid sorbent (polyurethane foam). For the measurements of PAH in emission, gas chromatography and mass spectrometry were used which make it possible to identify and determine 16 PAH compounds in the samples; this method was used for HCB determination also. Gas chromatography with ECD detector was used for PCB measurement. It was detected that the levels of PAH emission from wastes uncontrolled burning of wastes vary greatly. Influencing factors are composition and properties of refuse, temperature and mode of burning, level air supply. Generally, the increase of content of wood leads to the increase of PAH in emission. PAH emission also increased with increasing temperature of burning. The highest PAH values are characteristic of emissions from domestic refuse burning. Practically, all naphthalene, acenaphthylene, acenaphthene (from 60% to 100% of their total mass) and fluorene (14%-99%) were emitted in gaseous form.  相似文献   

16.
Sally Eden 《Geoforum》2012,43(5):1014-1023
This paper examines how environmental resources are measured and quantified as objects of environmental science and management and how lay knowledge-producers participate in this process, alongside the state. Using a case study of recreational angling, I show how fish in English rivers and lakes are counted and anglers act as lay or amateur knowledge-producers in the state’s metrological knowledge-practices. As embodied measurement instruments, anglers create data about themselves (as ‘effort data’) and about fish (as ‘catch returns’). These data are combined with other forms of data produced by the Environment Agency in England and Wales and used for fisheries management, thus shaping water bodies and fish ecology. I show how, to support environmental measurement, the state manages not only the environment and fish, but also anglers as lay knowledge-producers, using both regulation and economic incentives; in response, anglers also use data reflexively and strategically. I therefore emphasise the heterogeneous co-productions of environmental measurement as amateur–professional, human–animal and organic–technological, and show how measuring and managing water ecologies also involves measuring and managing humans.  相似文献   

17.
18.
The area defined as the N — S transect of Central Europe encompasses Slovenia, Croatia, Hungary, southern Slovakia, northern Austria, Moravia and southern Poland. Physical and biological environmental analysis have been undertaken for the Gravettian period of the last glacial, between 31 and 22 ka cal BP. Mammal faunas have been recorded from different provinces, which have climatic differences. These climatic differences are reflected in the sediments, the plant cover and the fauna. Over the course of several warm and cold events from 31–22 ka the biodiversity of the individual provinces has remained roughly the same, but important quantitative changes have occurred in the individual faunas.  相似文献   

19.
The determination of natural and artificial radionuclides, such as Th, U and Pu isotopes, in the marine environmental studies is important and has been an active research field in the environmental analytical geochemistry. For example, uranium isotope ratios give information regarding the source of the uranium in the environment, and are important for studying its biogeochemical behavior, while thorium isotope (^230Th) and Pu isotopes are good tracers for particle scavenging process study in the ocean. Due to the extremely low concentrations of these radionuclides in the marine environment, the accurate analysis of these radionuclides is still a challenging task. In this presentation, we will present the recent development of highly sensitive analytical methods for ^230Th, ^234U, ^235U, ^238U, ^239Pu and ^240Pu and their isotope ratios (^234U/^238U, ^235U/^238U, ^240Pu/^239Pu) in radionuclides in marine environmental samples, such as seawater, sediments, settling particles, using quadrupole and sector field ICP-MS. Applications of the radionuclide analysis in the marine environmental studies, such as the radioactivity environmental monitoring,  相似文献   

20.
The bentonite deposit of Lahij Province, Yemen, has very promising commercial applications due to its mineralogy and physical and chemical properties. It was examined to determine its mineralogical composition, chemical and physical properties of the bentonite deposit, purity and sodium-exchanged bentonite. Modified bentonite was synthesized by exchanging cetyltrimethylammonium cations for inorganic ions on the bentonite and its adsorption properties for ammonium were characterized in batch experiments. Analytical methods were carried out to study the bentonite comprising X-ray diffraction (XRD), scanning electron microscopy (SEM), infrared spectroscopy, chemical analysis and kinetic and isotherm models were also tested. The results have shown that the purification of bentonite resulted in a bentonite fractions of the total sample composed of montmorillonite and <5 % quartz. The XRD data showed that the interlayer spacing (d 001) of bentonite decreased from 15.3 to 12.5 Å and then increased to 19.7 Å. Moreover, high cation exchange capacity, good water absorption and high swelling capacity were also obtained. The results have shown that the modified bentonite was more effective than the natural bentonite for ammonium removal. In addition to that, pseudo-second-order kinetic model, Freundlich and the Langmuir models described the adsorption kinetics and isotherm well. It was concluded that Yemen (Alaslef) bentonite can be potential adsorbents for ammonium removal.  相似文献   

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