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761.
This paper provides data on baseline concentrations, interrelationships and bioconcentration potential of 12 metallic elements by King Bolete collected from 11 spatially distant sites across Poland. There are significant differences in concentrations of metals (Al, Ba, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Sr, Zn) and their bioconcentration potential in King Bolete Boletus edulis at 11 spatially distant sites surveyed across Poland. These have resulted from significant geographical differences in trace metal concentrations in a layer (0-10 cm) of organic and mineral soil underneath to fruiting bodies and possible local bioavailabilities of macro- (Ca, K, Mg, Na) and trace metals (Al, Ba, Cd, Cu, Fe, Mn, Sr, Zn) to King Bolete. The use of highly appreciated wild-grown edible King Bolete mushroom has established a baseline measure of regional minerals status, heavy metals pollution and assessment of intake rates for wild mushroom dish fanciers against which future changes can be compared. Data on Cd, Cu and Zn from this study and from literature search can be useful to set the maximum limit of these metals in King Bolete collected from uncontaminated (background) areas. In this report also reviewed are data on Al, Ba, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, Sr and Zn accumulation in King Bolete.  相似文献   
762.
可见光活性纳米TiO2光催化涂料的抗菌性能研究   总被引:1,自引:0,他引:1  
基于过渡金属离子掺杂技术,制备了在室内光辐照条件下具有良好光催化抗菌性能的可见光响应型铁掺杂TiO2光催化涂料。研究结果表明,在可见光活性光催化涂料中添加1%的纳米TiO2时,抗菌效果最好,光照24 h后对大肠杆菌、白色念珠球菌、黑曲霉的杀菌率分别达到99.9%、97.2%、82%。采用致孔剂聚乙二醇6 000对光催化剂改性后,能加快该涂料的抗菌性能,光照6 h后杀菌率就能达到99.9%。表明该涂料在室内可见光照射下具有较好的广谱抗菌效果,能抑制和杀灭多种微生物。  相似文献   
763.
The aim was to determine half-life of six most abundant PCB congeners in the body of early adolescents. In 304 environmentally exposed children, PCB serum concentration was determined at the age of 8 and 12 years. Half-life was determined for each child assuming exponential decrease or for the whole cohort using multiple regression. Results obtained by both approaches were in agreement. PCB reuptakes corrupting half-life estimates for each child and each congener were evaluated. If one of the serum PCB concentration values fell below the level of detection (LOD) the pair was excluded and if PCB half-life value exceeded the arbitrary value of 30 years. The following median half-lives in years 4.46, 10.59, 9.7, 4.7, 9.1 and 9.8 were obtained for PCB congeners 118, 138+163, 153, 156+171, 170 and 180, respectively. The elimination half-life values were not systematically related to PCB serum concentration at any examination age. Between half-life values, percentage of children with significant reuptakes and PCB congener abundance in serum were found significant associations.  相似文献   
764.
Goi A  Viisimaa M  Trapido M  Munter R 《Chemosphere》2011,82(8):1196-1201
Calcium and magnesium peroxides were applied for the treatment of soil contaminated by polychlorinated biphenyls-containing electrical insulating oil (Aroclor 1016). The removal of PCB-containing electrical insulating oil was achieved with the addition of either calcium peroxide or magnesium peroxide alone and dependent on dosages of the chemical. A 21-d treatment of 60% watered soil with the moderate addition (chemical/oil weight ratio of 0.005/1) of either calcium peroxide or magnesium peroxide resulted in nearly complete (96 ± 2%) oil removal, unsubstantial increase in soil pH and almost no changes in oxygen consumption and dehydrogenase activity, making it suitable for the soil decontamination.  相似文献   
765.
Based on consumption data statistics, food items from four regions in Sweden were sampled in a so-called market basket study. Food items from five food groups, i.e. fish, meat, dairy products, eggs and fat/oils, were analyzed for persistent organic pollutants (POPs) followed by per capita intake calculations. The highest levels of PCDD/F, PCB, PBDE, HBCD and chlorinated pesticides were found in the fish/fish products. The estimated market basket per capita intake of PCDD/F and dl-PCB was 0.7 pg WHO-TEQ kg bw−1 d−1 (TEFs from 1998). The intake of ∑PCB was estimated to 4.9 ng kg bw−1 d−1 and fish was found to be the major contributor with 64%. The intake of ∑PBDE was found to be 0.7 ng kg bw−1 d−1. Fish (38%) and dairy products (31%) were the largest contributors to the total PBDE intake. The intake of HBCD was estimated to 0.14 ng kg bw−1 d−1. HBCD mainly came from fish (65%), but also dairy products (24%) and meat (10%) contributed. Also regarding the chlorinated pesticides, fish was found to be the major contributor, with 51% of the ∑DDT coming from fish. The intake of ∑DDT, ∑HCH and HCB was 4.0, 1.0 and 1.1 ng kg bw−1 d−1, respectively. Most of the ∑HCH and HCB originate from dairy products (43% and 55%, respectively). This study shows that the levels, and intake, of different POPs from food of animal origin in the market basket of 2005 seem to have decreased since the market basket study in 1999.  相似文献   
766.
Szopka K  Karczewska A  Kabała C 《Chemosphere》2011,83(11):1507-1512
The study was aimed to examine total concentrations and pools of Hg in surface layers of soils in the Karkonosze Mountains, dependent on soil properties and site locality. Soil samples were collected from a litter layer and the layers 0-10 cm and 10-20 cm, at 68 sites belonging to the net of a monitoring system, in two separate areas, and in three altitudinal zones: below 900 m, 900-1100 m, and over 1100 m. Air-borne pollution was the major source of mercury in soils. Hg has accumulated mainly in the litter (where its concentrations were the highest), and in the layer 0-10 cm. Hg concentrations in all samples were in the range 0.04-0.97 mg kg−1, with mean values 0.38, 0.28, and 0.14 mg kg−1 for litter and the layers 0-10 cm and 10-20 cm, respectively. The highest Hg concentrations in the litter layer were found in the intermediate altitudinal zone, whereas Hg concentrations in the layer 0-10 cm increased with increasing altitude. Soil quality standard for protected areas (0.50 mg kg−1) was exceeded in a few sites. The pools of Hg accumulated in soils were in the range: 0.8-84.8 mg m−2, with a mean value of 16.5 mg m−2, and they correlated strongly with the pools of stored organic matter.  相似文献   
767.
This paper presents the performance analysis of a power plant with the Organic Rankine Cycle (ORC). The power plant is supplied by thermal energy utilized from a solar energy collector. R245fa was the working fluid in the thermodynamic cycle. The organic cycle with heat regeneration was built and tested experimentally. The ORC with a heat regenerator obtained the maximum thermodynamic efficiency of approximately 9%.  相似文献   
768.
In this study, tebuconazole (TEB)-loaded poly-3-hydroxybutyrate (P3HB)-based microparticles were developed and comprehensively characterized. TEB-loaded microparticles with the initial loading amounts of the fungicide of 10, 25, and 50% of the polymer mass (TEB 10, TEB 25, and TEB 50%) were prepared using emulsion technique. Encapsulation efficiency of TEB varied from 59 to 86%. As the loading amount was increased, the average diameter of microparticles increased too, from 41.3 to 71.7?µm, while zeta potential was not influenced by TEB loading, varying between –32.6 and –35.7?mV. TEB was gradually released from the microparticles to the model medium, and after 60?d, from 25 to 43% of TEB was released depending on the content of the encapsulated fungicide. The data obtained from in vitro TEB release were fitted to different mathematical models. It was shown that the release profiles of TEB could be best explained by the Zero-order, Higuchi, and Hixson–Crowell models. The antifungal activity of the P3HB/TEB microparticles against phytopathogenic fungi Fusarium moniliforme and Fusarium solani was demonstrated by in vitro tests conducted in Petri dishes. Thus, hydrophobic agrochemicals (TEB) can be effectively encapsulated into P3HB microparticles to construct slow-release formulations.  相似文献   
769.
Regional Environmental Change - The published online version contains mistake. Anna Maria Jönsson was inadvertently omitted in the author group section. Correct author group section is shown...  相似文献   
770.
This paper deals with sustainability in cities and the role technology plays in furthering sustainable results. Recently, many interventions have been implemented in cities to propose paths and models promoting the sustainability of cities from an overall perspective. Technologies are favouring the achievement of aims recalling the three spheres of sustainability as proposed by Arcadis (2017), namely “planet”, “profit”, and “people”. The ties between technology and the three spheres are investigated through a content analysis of reports issued by the 10 cities with the most significant advances in terms of becoming sustainable cities, as indicated in the Arcadis Report 2016. The results highlight technology as an element crossing sustainability, as processes and models in cities management and service provisions to citizens are significantly changing. New tools are innovating the processes addressing environmental issues, thus leading to cost efficiency and better economic conditions. Parallel to this, new models for city management and the provision of public services are addressing the need for a better quality of life for citizens and cities’ other stakeholders. Technology itself is thought of as sustainable because it should lead to efficiency and being efficient itself. A qualitative cluster analysis and a focus on excerpts from reports are proposed to highlight the ties between technologies and the elements representing key issues in managing and leading a city towards more sustainable conditions.  相似文献   
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