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51.
Polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), polychloronaphthalenes (PCNs) and coplanar PCBs were measured in surface sediments from 18 lake areas in Central Finland. Toxic 2, 3, 7, 8-substituted PCDD and PCDF congeners occurred at low levels (<20 − 230 pg/g dw). PCNs appeared at few ng/g (total PCNs) levels. Pulp mills or any other local sources could not be associated with the sedimented PCDDs, PCDFs and PCNs. Coplanar PCB congeners 77 and 105 (IUPAC Nr) were generally found at 20–550 pg/g levels. The most toxic congener 126 was measured (110 pg/g) only at one area near a local PCB leakage. Pulp mill originated aromatic chlorocompounds which coelute with PCDDs and PCDFs in clean up, probably alkyl polychlorobibenzyls (R-PCBBs) appeared at ng/g levels and showed a clear gradient dowstreams from pulp mill effluent points. 相似文献
52.
53.
Sanni Eloneva Eeva-Maija Puheloinen Jaakko Kanerva Ari Ekroos Ron Zevenhoven Carl-Johan Fogelholm 《Journal of Cleaner Production》2010,18(18):1833-1839
The steel industry is characterised by large amounts of CO2 emissions, but there is no easy means to reduce these emissions. One interesting option for the reduction of CO2 emissions could be the utilisation of steelmaking slags for carbon dioxide mineralisation. In this option CO2 is bound with the calcium of the slag material, producing stable carbonate as an end product. The utilisation of steelmaking slags as the raw material for carbon dioxide mineralisation will change the quality of the slags. If, however, this change degrades the slags it could prevent the use of slags in carbon dioxide mineralisation or make it very expensive.The purpose of the research presented here is to evaluate this issue with the help of a case study where the quality of the residual slag from the recently suggested carbonation method was experimentally investigated. The CO2 mineralisation method, based on steelmaking slags and ammonium salt solutions, was found to change the quality of the slags: the calcium content was reduced, the CaO and Ca(OH)2 phases were completely dissolved, and the solubility of the V and Cr increased notably. This residual slag would presumably have to be handled as waste. Currently, the steelmaking slag used in the case study is defined as a by-product, but if it is used for CO2 mineralisation instead of liming its legal status will be re-evaluated. Subsequently, the CO2 mineralisation process could possibly be defined as an end-of-waste procedure. 相似文献
54.
Miranda M. Loh Joana Soares Ari Karppinen Jaakko Kukkonen Leena Kangas Kari Riikonen Anu Kousa Arja Asikainen Matti J. Jantunen 《Atmospheric environment (Oxford, England : 1994)》2009,43(2):301-310
The intake fraction (iF) gives a measure of the portion of a source's emissions that is inhaled by an exposed population over a defined period of time. This study examines spatial and population-based iF distributions of a known human carcinogen, benzene, from a ubiquitous urban source, local vehicular traffic, in the Helsinki Metropolitan Area using three computational methods. The first method uses the EXPAND model (EXPosure to Air pollution, especially to Nitrogen Dioxide and particulate matter), which incorporates spatial and temporal information on population activity patterns as well as urban-scale and street canyon dispersion models to predict spatial population exposure distributions. The second method uses data from the personal monitoring study EXPOLIS (Air Pollution Exposure Distributions of Adult Urban Populations in Europe) to estimate the intake fractions for individuals in the study. The third method, a one-compartment box model provides estimates within an order-of-magnitude or better for non-reactive agents in an urban area. Population intake fractions are higher using the personal monitoring data method (median iF 30 per million, mean iF 39 per million) compared with the spatial model (annual mean iF 10 per million) and the box model (median iF 4 per million, mean iF 7 per million). In particular, this study presents detailed intake fraction distributions on several different levels (spatial, individual, and generic) for the same urban area. 相似文献
55.
Chemical sequential extraction of heavy metals and sulphur in bottom ash and in fly ash from a pulp and paper mill complex 总被引:2,自引:0,他引:2
Hannu Nurmesniemi Risto P?yki? Toivo Kuokkanen Jaakko R?m? 《Waste management & research》2008,26(4):389-399
A five-stage sequential extraction procedure was used to determine the distribution of 11 metals (Cd, Cr, Cu, Mo, Pb, Zn, As, Co, V, Ni, Ba), and sulphur (S) in bottom ash and in fly ash from a fluidized bed co-combustion (i.e. wood and peat) boiler of Stora Enso Oyj Oulu Mill at Oulu, Northern Finland, into the following fractions: (1) water-soluble fraction (H2O); (2) exchangeable fraction (CH3COOH); (3) easily reduced fraction (NH2OH-HCl); (4) oxidizable fraction (H2O2 + CH3COONH4); and (5) residual fraction (HF + HNO3 + HCl). Although metals were extractable in all fractions, the highest concentrations of most of the metals occurred in the residual fraction. From the environmental point of view, this fraction is the non-mobile fraction and is potentially the least harmful. The Ca concentrations of 29.3 g kg(-1) (dry weight) in bottom ash and of 68.5 g kg(-1) (dry weight) in fly ash were correspondingly approximately 18 and 43 times higher than the average value of 1.6 g kg(-1) (dry weight) in arable land in Central Finland. The ashes were strongly alkaline pH (approximately 12) and had a liming effects of 9.3% (bottom ash) and 13% (fly ash) expressed as Ca equivalents (dry weight). The elevated Ca concentrations indicate that the ashes are potential agents for soil remediation and for improving soil fertility. The pH and liming effect values indicate that the ashes also have a pH buffering capacity. From the environmental point of view, it is notable that the heavy metal concentrations in both types of ash were lower than the Finnish criteria for ash utilization. 相似文献
56.
P. Pessala J. Kernen E. Schultz T. Nakari M. Karhu H. Ahkola J. Knuutinen S. Herve J. Paasivirta J. Ahtiainen 《Chemosphere》2009,75(11):1506-1511
The aerobic biodegradation of commercial nonylphenol ethoxylate (NPE) mixture and alkali lignin was studied using the OECD headspace test accompanied by the simultaneous measurement of ecotoxicity directly from the biodegradation liquors and by the follow-up of the chemical composition of the studied chemicals. NPE degradation was dependent on the inoculum source: approximately 40% of NPE was mineralized into CO2 during the 4-week experiment when inoculum from Helsinki City wastewater treatment plant (WWTP) was used, and only 12% was mineralized when inoculum from Jyväskylä City WWTP was used. Chemical analyses revealed a shift in the ethoxylate chain length from longer to shorter soon after the beginning of the NPE biodegradation tests. At the same time also toxicity (reverse electron transport assay, RET) and estrogenic activity (human estrogen receptor yeast) measured directly from the biodegradation liquors decreased. In case of alkali lignin, approximately 11% was mineralized in the test and chemical analysis showed in maximum a 30% decrease in lignin concentration. Toxicity of lignin biodegradation liquors started to decrease in the beginning of the test, but became more toxic towards the end of the test again. Especially RET assay proved to be sensitive enough for measuring toxicity changes directly from biodegradation liquors, although a concentrating treatment of the liquors is recommended for a more detailed characterization and identification of toxic metabolites. 相似文献
57.
Khoroshko LO Petrova VN Takhistov VV Viktorovskii IV Lahtiperä M Paasivirta J 《Environmental science and pollution research international》2007,14(6):366-376
Background, Aims and Scope Despite the large number of studies on the forms of sulfur in marine deposits, investigations on sulfur organic compounds
are still rare. It is known that the processes leading to formation of intermediate and final sulfur compounds (including
organic ones) in modern deposits are the results of microbiological transformation of sulfur containing proteins, as well
as the microbiological reduction of sulfate ions. The latter are finally reduced by anaerobic sulfate-reducing bacteria to
H2S, HS− and S2−; the total sum of these is referred to as ‘hydrogen sulfide’ in chemical oceanography. Further, the formation of reduced
sulfur organic derivatives (sulfides and polysulfides) is the result of interaction of the organic substance destruction products
with the sulfide ions. In such cases, the main source of organic substances, as well as sulfates for the sulfur reducing processes,
is the pore water in the sediments. The choice of the target of our study is based on the fact that the eastern part of the
Gulf of Finland water area receives the bulk of the anthropogenic load of the St. Petersburg region. Low vertical intermixing
of the water thickness is observed there (thus creating a deficiency of oxygen near the bottom), and the bottom sea current
transfers the polluted salty water of the Baltic Sea into the Neva Bay. The whole of the above are the preconditions for the
formation of sulfur-bearing organic compounds.
A great number of bottom sediment samples for analytical surveys were collected in the Eastern Gulf of Finland during research
expeditions in the years of 1997 and 2001. These were screened for structures of sulfur organic microcontaminants, including
organic forms of sulfur, using advanced instrumentation and experienced personnel in our two, cooperating laboratories. This
work is a part of the research being carried out on organic micro-admixtures present in bottom sediments, and is the summary
of our findings on previously unstudied sulfur organic substances there.
Materials and Methods A number of sulfur organic compounds present in nineteen bottom sediment samples from the Eastern Gulf of Finland (EGF) were
characterized by high performance gas chromatography connected to low and high resolution mass spectrometers (GC/LRMS and
GC/HRMS). The structure screening was carried out as compared with literature and library mass spectra, and taking the GC
retention times into account. In the cases of an absence of mass spectra not in the literature, interpretation of the most
probable structures was performed with the help of high resolution mass-spectrometric data, fragmentation rules for sulfur-bearing
organic substances and ICLU simulation of spectra. These data were registered to form a conclusive ‘fingerprint’ for identification
and confirmation of the structure of each novel compound found, e.g. by later syntheses of authentic model compounds. The
relative contents of sulfur organic compounds were determined from MS response ratios of each compound to 2-fluorine naphthalene
(internal standard).
Results This paper is a completion of work, which has been published in part as three papers in the European Journal of Mass Spectrometry.
As the total study result, 43 sulfur-bearing compounds were characterized. The mass spectra of 20 of them were found in the
literature. The most probable structures for the 23 compounds whose mass-spectra were not available in the literature data
were proposed. All of those 23 compounds were detected in bottom sediments for the first time, and 5 of them were described
as originating from plants or being generated by chemical synthesis products, while the remaining 18 substances were previously
unknown. The structures of these were deduced to be most probably the following (in order of their GC retention): dichloromethyl
thiylsulfenylchloride, chloromethyl dichloromethyl disulfide, 3,4-dithiacyclohexene, 1,2,4-trithiacycloheptane, 1,2,3-trithiacyclohexane,
tetrathiacyclopentane, 3,4,5-trithiacyclohexene, 1,2,4-trithiacyclohexane, cyclopropylhydrotrisulfide, 1,2-dithiane-3-thiol,
1,3-dithiane-2-thiol, bis(trichloromethyl)-tri-sulfide, 1,2,4,5-tetrathiacyclohexane, 1,2,3,4-tetrathiacycloheptane, 1,2,3,4-tetrathiacycloheptane,
1,2,3,4-tetrathia-cyclo-hexane, pentathiacyclohexane, and 1,2,4,6-tetrathiacyclooctane. The highest amounts of sulfur organic
compounds were found in the deepest, bottom areas in the open part of the sea, where the salinity was highest, and oxygen
deficiency occurred as well. Also, some coastal places with a high solid matter deposition rate had elevated contents of sulfur
organic compounds.
Discussion From the 43 sulfur organic compounds found, the HRMS data provided the atomic composition of the molecular ions for 16 compounds
with a high confidence (see Table 3). The LRMS spectra could be identified with catalogue or literature spectra in 29 cases.
The MS information obtained was insufficient in two cases: 1) The obvious molecular ion (at m/z 110) of compound 1 was not
visible in LRMS. 2) For compound 43, the HRMS measurement, due to the low intensity (2%) of the molecular ion (m/z 210), could
not exclude the presence of 2 oxygen atoms (instead of one sulfur atom) in the molecule. Major fragments, however, of our
43, certainly contained no oxygen atoms according to HRMS. The limited LRMS data in the literature, for an isomer of 43, had
m/z values of all fragments different from those of the compound found by us.
The retention times (RT) formed one more evidence for identity between compounds in different samples. The use of different
non-polar columns in GC and similar, but not identical, temperature programs produced eluted peaks of novel and known compounds
in each sample (mixture) in GC/HRMS and GC/LRMS. These gave sets of RTs which were in a very significant linear correlation
(measured example R = 0.999866, p = 1.85E-06, N = 5). Therefore, the RTs in the HRMS analysis systems could be converted to
values comparable with those from the LRMS device.
The RT values, HRMS m/z values, LRMS spectra, and ICLU simulation results for each organic sulfur compound form an identification
‘fingerprint’. The interpretation of these experimental data, with supporting use of fragmentation rules, allow the giving
of a provisional name and structure to the ‘suspect’. In this study and in environmental surveys of micropollutants in general,
the compounds suspected of anthropogenic or natural origin occur at low levels in complex mixtures. Therefore, no bulk amount
of an authentic, pure model substance for the suspect is available quite often. The most probable name and structure from
the fingerprint data are very useful in guiding the preparation of the model substance for a conclusive identification. Similarly,
the unknown criminal can be identified in advance by forensic science and his fingerprint, DNA, etc. as registered before
the arrest. The analogy can be found in the literature and CAS register of organic polysulfides, which in great part consists
of the results of sensitive mixture analysis methods.
Conclusions Sediment of the Eastern Gulf of Finland is over large areas anaerobic, as indicated by the existence of novel, non-oxygenated
sulfur organic microcontaminants. These substances were most abundant in anoxic and saline, deep bottom regions, and, in addition,
in one coastal area near industrial discharges. This occurrence, and also the limited information about sulfur organic compounds
in scientific literature, is considered evidence for the dominantly natural processes in their formation.
Recommendations and Perspectives The importance and necessity of investigating the sulfur organic compounds in the bottom sediments, result from the fact that
their presence can be an indicator of stable anaerobic processes. Similarly, the oxygen disappearance (anoxia) in the marine
water, due to a high concentration of the sulfate ions and relatively high content of organic matter, is practically always
connected with the appearance of hydrogen sulfide and sulfides. The generation of sulfur organic compounds precedes the formation
of the new, or expansion of the existing anaerobic (‘hydrogen sulfide’) zones, which lead to such environmental disasters
as mass destruction of hydrobionts. Many organic compounds of sulfur, including sulfides and polysulfides, are toxic to the
aquatic organisms. Therefore, in addition to the danger of mass wholesale deaths of marine fauna in the bottom sediments region,
there exists a probability of secondary pollution of the water thickness as well, due to the entry of those substances from
bottom sediments in the water when the environmental conditions are changed (stormy weather, floods, geological activity of
the earth’s crust, etc.). 相似文献
58.
Ivan Holoubek Jaakko Paasivirta Paula Maatela Mirja Lahtiperä Irena Holoubková Pavel Korínek 《毒物与环境化学》2013,95(2-3):137-154
Different sample preparation methods for the determination of polycyclic aromatic hydrocarbons (PAHs) in lake and river sediments were compared and evaluated. Freeze‐dried sediment materials were extracted using Soxhlet extraction, ultrasonic agitation and digestion with various solvents and solvent mixtures. Similarly, clean‐up methods using various types of sorbents for separation of PAHs tested. The following method gives the best results for the determination of PAHs: freeze‐dried sediment samples were extracted using Soxhlet extractor with dichloromethane (6 hr, dark), extracts were cleanup using Silica gel and a mixture of n‐hexa‐ne‐dichloromethane was used for the elution of PAHs. This method was used for the determination of 7 selected PAHs in sediment samples from Finnish lakes and Czech streams. 相似文献
59.
Arctic cod liver samples from Vestertana Fjord at the Arctic coast of Norway, salmon and guillemot samples from the Baltic Sea and the Atlantic Ocean, and salmon and lamprey larva samples from Kymijoki River in southern Finland were analysed for the occurrence of tri-, tetra- and pentabromomethoxy diphenyl ethers and their concentration levels were estimated. These compounds have previously been identified by other research groups in salmon, seal and dolphin samples. The aim of this study was to find out a possible temporal trend in the concentrations of these compounds in the cod liver samples from years 1987-1998 and to investigate the possible spatial differences in the concentrations in biota samples from the Baltic Sea, Atlantic Ocean, Arctic Sea and contaminated freshwater river. Two most abundant methoxy-tetrabromo diphenyl ether congeners occurred in the same statistically significant ratio in 14 sea biota samples. Levels in lamprey larvae were below detection limit. The origin of these methoxylated bromodiphenyl ethers in biota samples remained unknown. They may be metabolites of polybrominated diphenyl ethers used as flame retardants or compounds of natural origin. 相似文献
60.
Paula Maatela Jaakko Paasivirta Michail A. Grachev Evgeny B. Karabanov 《Chemosphere》1990,21(12):1381-1384
Organically bound chlorine (OCl) together with inorganic chloride (Cl−) was measured from bottom surface samples of the Lake Baikal near a pulp mill and compared to organic matter contents (OM). Although total contents of OCl, Cl− and OM were much lower than, the ratio of OCl to OM was of the same order of magnitude as in pulp mill recipients of Finland. 相似文献