首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   22篇
  免费   0篇
  国内免费   2篇
安全科学   1篇
废物处理   1篇
综合类   3篇
基础理论   1篇
污染及防治   13篇
评价与监测   4篇
社会与环境   1篇
  2021年   1篇
  2019年   2篇
  2015年   1篇
  2014年   2篇
  2013年   3篇
  2012年   2篇
  2011年   3篇
  2010年   2篇
  2009年   4篇
  2008年   1篇
  2003年   1篇
  2002年   1篇
  1999年   1篇
排序方式: 共有24条查询结果,搜索用时 31 毫秒
1.
This paper presents and discusses the levels and temporal trends of concentrations of Cd, Pb, Hg, Cu, Zn, and As in livers and Hg in the muscle tissues of cod (Gadus morhua L) from the Baltic Sea during the period 1994–2010. Concentrations of Pb, Hg, and Cd exhibited significant downward trends. Cu and Zn concentrations exhibited upward trends in the period 1994 to 2010. No trends were detected for concentrations of As. The temporal trends identified in heavy metal concentrations in cod livers corresponded to the directions of changes in concentrations of these elements introduced into the Baltic Sea via river runoff and atmospheric emission, and those in surface and deep waters of the Baltic. Downward trends in the concentrations of toxic metals in cod livers suggest that advantageous changes are occurring in concentrations of heavy metals in the environment of the southern Baltic Sea.  相似文献   
2.
The results of tests for the purification of fish oils with activated carbon for industrial use are presented. The optimum parameters for the process of purification (granulation of the activated carbon, its dosage, the oil temperature, and the duration of mixing the oil with activated carbon) were previously established for the laboratory scale. The optimization of the process consisted of selecting purification parameters that would allow for maximum reduction of the toxic polychlorinated dibenzo-para-dioxins and polychlorinated dibenzofurans (PCDD/Fs) content, while retaining the favorable high fatty acid content [C20:5 n−3, eicosapentaenoic acid (EPA) and C22:6 n−3, docosahexaenoic acid (DHA)]. The use of that optimum parameters in industrial conditions confirmed the satisfactory results obtained in laboratory tests. Five types of oil derived from various Baltic fish were purified. Reduction in the PCDD/Fs content was 77.0–93.6% on average, whereas in the dioxin-like polychlorinated biphenyls (dl-PCBs)—it was 42.7–50.5% on average, with insignificant changes in the total amount of EPA and DHA content. Furthermore, a significant reduction in the content of arsenic was noted (by about 62% on average), with insignificant changes in the content of organochlorine pesticides (OCPs), and marker polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), cadmium, lead, and mercury.Purification provided fish oil having standardized parameters that allow for its use as feed additives, whilst retaining its favorable fatty acid content.  相似文献   
3.
Chemical analyses were performed in nine fish species that are popular on the Polish market. These included Baltic fish (cod, herring, salmon), fish farmed in Poland (carp, trout), marine fish imported from China (Alaska pollock, sole), and farmed fish imported from Vietnam and China (sutchi catfish, tilapia). The nutritional composition (amino acid, micro- and macronutrients, fat-soluble vitamins - A1, D3, E) and certain contaminants (organochlorine pesticides, OCPs; indicator polychlorinated biphenyl, PCB6; polychlorinated dibenzo-paradioxins and polychlorinated dibenzofurans, PCDD/Fs; dioxin-like polychlorinated biphenyls, dl-PCBs; organotin compounds, OCTs; dyes, malachite green and crystal violet; veterinary drug residues, nitrofurans and chloramphenicol; toxic metals, Cd, Pb, Hg) in the muscle tissues of fish were determined. It was confirmed that the fish species analyzed were excellent sources of amino acids, and were rich in phosphorous and selenium. Baltic Sea fish (salmon, herring), fish farmed in Poland (carp and trout), and tilapia were also rich in vitamin D3.Traces of OCP, PCB6, OCT, dyes, veterinary drug residues, and heavy metals were detected in concentrations which do not pose a threat to consumers at the current rate of fish consumption in Poland. However, the problem might arise from the content of PCDD/Fs and dl-PCBs in fatty Baltic fish. The fish species analyzed, differed in their nutritional values and degrees of contamination. We suggest that for optimum health and safety, it is advisable that consumers include a variety of different fish species in their diets.  相似文献   
4.
Fluoride concentrations were determined in PM10 samples collected in the urbanized coastal area of the Baltic Sea (Gdynia) in the period between 1 August 2008 and 8 January 2010. F? concentrations remained within the range of 0.4–36.6 ng?·?m?3. The economic transformations which have taken place in Poland increasing ecological awareness have had an excellent effect on the levels of fluoride pollution in the air of the studied region. In our measurements, fluoride concentrations increased in wintertime, when air temperature dropped, at low wind speeds (<1 m?·?s?1) and with low dispersion of pollutants originating from local sources (traffic, industry, domestic heating). At times when wind speed grew to >10 m?·?s?1, fluorides were related to marine aerosols or else brought from distant sources. Apart from wind speed and air temperature, other significant meteorological parameters which determined the variability of F? turned out to be air humidity and precipitation volume. Aerosols were washed out effectively, even with small precipitation (h?=?4 mm), and if a dry period lasted for several days, their concentrations grew rapidly to over 30.0 ng?·?m?3.  相似文献   
5.
Purpose. The aim was to adjust the positive health behaviours scale (PHBS) to make it suitable for use by nurses, and to validate the new version of the tool. Methods. A previously formulated PHBS was modified. The scale comprises 29 statements describing certain positive health behaviours in four subscales: nutrition, physical activity, relaxation and behaviours related to mental health, and preventive behaviours. The scale was enriched with items on avoiding risky behaviours and a question regarding respondents’ own assessment of their care for health. Analyses were conducted of reliability, construct validity, criterion validity and dimensionality of subscales. The questionnaire was completed by 1017 nurses. Results. Cronbach's α reached 0.844 for the entire scale and 0.623–0.761 for specific subscales. Empirical data did not confirm theoretical assumptions regarding the existence of a four-element structure of the PHBS. The scale's diagnostic criteria were validated on the basis of positive results of correlation and trend analysis. Only one of the subscales proved homogeneous and could be considered unidimensional. Conclusions. The results confirmed the high internal consistency of the scale and its subscales. The factor structure of the PHBS was equivocal. The PHBS could be used in workplace-based health promotion programmes designed for nurses.  相似文献   
6.
Environmental safety data are presented for [S,S]-Ethylene Diamine Disuccinate ([S,S]EDDS), a new, biodegradable, strong transition metal chelator. An environmental risk assessment for its use in detergent applications, which takes into account the chelating properties of [S,S]-EDDS, is proposed.

A property of [S,S]-EDDS that distinguishes it from other strong transition metal chelators is its, “ready” and transparent (no recalcitrant metabolites) biodegradation profile. Because its sorption to activated sludge solids is low ( Kp of 40 1/kg), removal of [S,S]EDDS during sewage treatment, which is greater than 96% as determined by the Continuous Activated Sludge test , is mainly ascribed to biodegradation. At projected use volumes in detergent applications [S,S] - EDDS predicted steady-state concentration in rivers leaving the mixing zone will be below 5 pg/I due to rapid biodegradation. [S,S]-EDDS exhibits low toxicity to fish and Daphnia ( both EC50s> 1000 mg/l). By contrast, due to limitation of the algal test for chelators apparent toxicity was observed (EC50 = 0.290 mg/l, NOEC - No observable Effect Concentration = 0.125 mg/l). Schowanek et al. [1] demonstrated that this is not toxicity sensu stricto but a chelation effect of trace metals in the test medium and of resulting essential nutrients limitation. This requires specific attention when the results of algal toxicity are to be extrapolated to a field situation to perform realistic risk assessment. Metal speciation calculations, using MINEQL+, show that at the predicted environmental concentrations of [S,S] - EDDS (1–5 μg/l), such a chelation effect would be insignificant. These calculations allow to estimate the NOEC for chelation effects in the field to be in the range of 0.250-0.500 mg/l, depending on the background water chemistry. These values are well above the laboratory NOEC.

An environmental risk assessment was performed using the EUSES (1.0) program. EUSES is currently the EU recommended tool for conducting risk assessments (TGD 1995). It was applied to estimate the river water and soil concentrations from production, formulation and private use life stages. The estimated PEC/PNEC ratio in all relevant environmental compartments is smaller than 1, indicating “no immediate concern” at the anticipated usage level.  相似文献   

7.
Wet deposition is an important source of metals to the sea. The temporal variability of Hg concentrations in precipitation, and the impact of air masses of different origins over the Polish coastal zone were assessed. Samples of precipitation were collected (August 2008–May 2009) at an urbanized coastal station in Poland. Hg analyses were conducted using CVAFS. These were the first measurements of Hg concentration in precipitation obtained in the Polish coastal zone. Since Poland was identified as the biggest emitter of Hg to the Baltic, these data are very important. In the heating and non-heating season, Hg concentrations in precipitation were similar. Hg wet deposition flux dominated in summer, when the production of biomass in the aquatic system was able to actively adsorb Hg. Input of metal to the sea was attributed to regional and distant sources. Maritime air masses, through transformation of Hg(0), were an essential vector of mercury in precipitation.  相似文献   
8.
Copper ore tailings were tested for the stability of titanium submitted to water leaching in three different reactor systems (agitated vessel, bioreactor and percolated fixed-bed column). For each of these systems, titanium extraction did not exceed 1% of the available metal. Biomass removed from ore residue adsorbed a small part of the titanium with sorption capacities below 20-30 mg g(-1), but most of this biomass was sequestered in the ore residue. Oxygen and carbon dioxide concentrations were monitored and changes in concentration correlated with bacteria development at the initial stage of the process and to fungal development in the latter stages.  相似文献   
9.
In Mediterranean seas and coastal zones, rivers can be the main source of mercury (Hg). Catchment management therefore affects the load of Hg reaching the sea with surface runoff. The major freshwater inflows to the Baltic Sea consist of large rivers. However, their systems are complex and identification of factors affecting the outflow of Hg from its catchments is difficult. For this reason, a study into the impact of watershed land use and season on mercury biogeochemistry and transport in rivers was performed along two small rivers which may be considered typical of the southern Baltic region. Neither of these rivers are currently impacted by industrial effluents, thus allowing assessment of the influence of catchment terrain and season on Hg geochemistry. The study was performed between June 2008 and May 2009 at 13 sampling points situated at different terrain types within the catchments (forest, wetland, agriculture and urban). Hg analyses were conducted by CVAFS. Arable land erosion was found to be an important source of Hg to the aquatic system, similar to urban areas. Furthermore, inflows of untreated storm water discharge resulted in a fivefold increase of Hg concentration in the rivers. The highest Hg concentration in the urban runoff was observed with the greatest amount of precipitation during summer. Moderate rainfalls enhance the inflow of bioavailable dissolved mercury into water bodies. Despite the lack of industrial effluents entering the rivers directly, the sub-catchments with anthropogenic land use were important sources of Hg in the rivers. This was caused by elution of metal, deposited in soils over the past decades, into the rivers. The obtained results are especially important in the light of recent environmental conscience regulations, enforcing the decrease of pollution by Baltic countries.  相似文献   
10.
A study was conducted to examine spinal deformities such as lordosis, scoliosis, and dwarfism in cod (Gadus morhua callaris L.) that were caught in the southern Baltic. The bone tissue of the spine and the muscle of the deformed cod were analyzed for concentration of macroelements (Sr, Ca and P) and toxic metals (Cd, Pb and Hg). Healthy specimens of the same body length that were caught in the same hauls were also tested, and these comprised the reference material. The study was undertaken to verify the hypothesis that lowered values of Ca/Sr and P/Sr ratios caused skeletal deformities. Toxic metals were also tested to determine whether they had an impact on the deformities of cod inhabiting Baltic waters. In cod with deformities, a significant decrease in Ca/Sr ratios were noted in 86% of the spine and 97% of the muscle. Decreases in the values of the P/Sr ratios were confirmed in 57% of the bone tissue and 78% of the muscle tissue of individuals with skeletal deformities. Toxic metals (Cd, Pb and Hg) occurred in the bone and muscle tissues of deformed and healthy cod on the low levels. It was not differences in concentrations of these elements, and thus could not have had an impact on the occurrence of deformities. Skeletal deformities could have resulted from lowered values of the Ca/Sr and P/Sr ratios of the spinal bone and muscle tissues of cod. Lower values of these coefficients should be linked to the varied salinity (5-21‰) and strontium (5-15Bqm(-3)) concentrations of Baltic waters.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号