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61.
Concentrations of toxic heavy metals (cadmium (Cd), lead (Pb)) and major nutritional and trace elements (Ca, Mg, P, Cu, Fe, Mn, Se, Zn) were analyzed in the milk of Simmental (n?=?20) and Holstein-Friesian (n?=?20) cows from an organic farm. Elements were determined using inductively coupled plasma emission atomic spectrometry. The conducted research showed that the milk of Simmental cows was characterized by the more advantageous mineral composition and lower concentration of noxious heavy metals compared to the milk of Holstein-Friesian cows. In the milk of Simmental cows, significantly lower concentrations of Pb and Cd (P?<?0.001) and Cu (P?<?0.05) and significantly higher concentrations of Fe and Mg (P?<?0.05) as well as nonsignificantly higher concentrations of Ca, Mn, and Se were found. In the milk of both breeds, very low Cu concentrations were recorded. The higher-than-recommended concentration of Pb in milk was also found. In the milk of both breeds, the significant positive correlations between concentrations of the following elements were observed: Pb–Cd, Pb–Se, Cd–Se, Cd–Mn, Zn–Cu, Zn–P, Ca–P, Ca–Mg, and Mg–P. The correlations between other elements within each of the analyzed breeds separately were also found.  相似文献   
62.
Environmental Science and Pollution Research - Quartz powder sourced from industrial wastes is very hazardous. It is because it contains large amounts of fine particles. Thus, it has the potential...  相似文献   
63.
Environmental Science and Pollution Research - This article presents a bibliometric study of 200 European publications released between 2001 and 2016, about the contamination of mushrooms by...  相似文献   
64.
Logarithmic values of the subcooled liquid vapor pressure (log PL) were estimated for 1436 polychlorinated and polybrominated congeners of benzenes, biphenyls, dibenzo-p-dioxins, dibenzofurans, diphenyl ethers and naphthalenes by employing the Quantitative Structure–Property Relationships (QSPR) approach. The QSPR model developed with GA–PLS technique was characterized by satisfactory goodness-of-fit, robustness and the external predictive performance (R2Y = 0.970, QCV2 = 0.970, QExt2 = 0.966, RMSEC = 0.21, RMSECV = 0.22 and RMSEP = 0.22). The externally validated model has been applied to predict subcooled liquid vapor pressure of uninvestigated halogenated persistent organic pollutants. Moreover, a simple arithmetic relationship between logarithmic values of subcooled liquid vapor pressures in pairs of chloro- and bromo-analogues has been found. This relationship can be used for estimating log PL of a brominated compound, whenever log PL of its chlorinated counterpart is known, without necessity of performing any time-consuming computations.  相似文献   
65.
Three soil types (sandy gravel, silty clay and sandy loam) from sites historically contaminated with total petroleum hydrocarbon (TPH) were amended with NH(4)NO(3) at concentrations ranging from 16 to 2133 mg/kg soil(dry weight). Microbial activity was measured as O(2) consumption and CO(2) production in order to assess nitrogen limitation. Although activity was stimulated in all three soils under NH(4)NO(3) amendment (after 72 h), the level of nitrogen required was soil specific. For the sandy gravel and silty clay soils, O(2) consumption and CO(2) production both showed enhanced microbial activity when amended with 16 mg/kg soil(dry weight) NH(4)NO(3), whereas, these two parameters gave differing results for the sandy loam soil. Specifically, CO(2) production and O(2) consumption were stimulated with 66 mg/kg and 133 mg/kg soil(dry weight) of NH(4)NO(3) respectively. In addition, respiratory quotient kinetic analysis suggested different decomposition processes occurring in this soil under different NH(4)NO(3) amendment concentrations.  相似文献   
66.
Several new biodegradable polymer materials have recently come onto the global market. Mostly the results on degradation kinetic studies are presented. This paper suggests using one of the tests to estimate the impact of polymer packaging material on sea life. The microorganism chosen was Anabaena variabilis (identified in many waters, including those of the Baltic Sea, especially in the Gulf of Gdańsk and Puck Bay; this cyanobacterium has a tendency to move with deep-sea waters causing algal blooms that upset the ecological balance of the marine environment [1]). The chosen polymer materials were polycaprolactone modified with thermoplastic starch (PCL/TPS > 85%) or with calcium carbonate (60% PCL/40% CaCO3). They were incubated in seawater in the presence of A. variabilis. The chlorophyll a content was determined as the criterion of cyanobacterial growth in the presence of the tested polymers. The polymer surface and colour changes in the cyanobacterium culture were recorded photographically. The experimental results indicate that the addition of polymer samples to the cyanobacterium culture affects its biological balance. During the experiment in seawater, cyanobacteria adhered to the polymer surfaces and their growth was stimulated to different degree by the polymers. Thus, the suggested test differentiate the behaviour of both materials studied. Cyanobacterial growth was lower in the presence of PCL modified with calcium carbonate than in the presence PCL/TPS blend.  相似文献   
67.
The capacity of laboratory-scale aerated biofilters to oxidize methane was investigated. Four types of organic and mineral-organic materials were flushed with a mixture of CH4, CO2 and air (1:1:8 by volume) during a six-month period. The filter bed materials were as follows: (1) municipal waste compost, (2) an organic horticultural substrate, (3) a composite of expanded perlite and compost amended with zeolite, and (4) the same mixture of perlite and compost amended with bentonite. Methanotrophic capacity during the six months of the experiment reached maximum values of between 889 and 1036 g m−2 d−1. Batch incubation tests were carried out in order to determine the influence of methane and oxygen concentrations, as well as the addition of sewage sludge, on methanotrophic activity. Michaelis constants KM for CH4 and O2 were 4.6-14.9%, and 0.7-12.3%, respectively. Maximum methanotrophic activities Vmax were between 1.3 and 11.6 cm3 g−1 d−1. The activity significantly increased when sewage sludge was added. The main conclusion is that the type of filter bed material (differing significantly in organic matter content, water-holding capacity, or gas diffusion coefficient) was not an important factor in determining methanotrophic capacity when oxygen was supplied to the biofilter.  相似文献   
68.
Coastal change and coastal erosion have been a long-existing source of environmental changes. Traditionally, regional changes in wetland systems and their relations to agriculture, industry and urbanization are a major cause for concern. Nowadays, coastal distress has reached even global proportions: the problems of coastal change are strongly linked to the loss of fragile ecosystems, eutrophication and loss of biodiversity. Given that over 70 % of all human activity is in coastal areas, it is clear that many environmental and socio-economic changes occur at a local level and manifest themselves in a spatial context. The physical effect on the geographic morphology is evident in the related consequences for land use. A deep understanding of the changes in land use, and simultaneously in coastal erosion, calls for the integrated monitoring of the most relevant effects in fragile regions. The Ria Formosa wetland system is a unique and very special wetland system in the Algarve (Portugal) and has been integrated in the NATURA 2000 network. The strong symbiosis between nature, agriculture and fisheries, as well as tourism, in the Algarve has led to spatial-ecological synergy. By using coastal recession analysis techniques by means of remote-sensed imagery from 1987, 1989, 2000 and 2007 and by combining this information with available data sets on surface erodibility, a cost surface on multitemporal transitions of land-use classes from the CORINE Land Cover data allows us to assess and integrate a decision-making framework by means of GIS. The novelty of this combined approach to land-use management is the blend of spatial analysis and remote-sensing techniques that share important information on ecosystems at risk. Our findings suggest a growing concern to the area brought by anthropogenic activity. This is studied to a spatial accounting of the distribution of land changes and transitions, where (1) a significant loss of coastal area is witnessed along the Ria Formosa, leading in particular to loss of agricultural land. (2) This loss is underpinned by an increase in leisure facilities to respond to the tourism demand of the region of the Algarve, while landscape metrics suggest that these areas are more volatile for coastal erosion. (3) Simulation through Markov chains on the land use and effects of urban, agricultural, forest and wetland dynamics suggests that by 2026, it is expected to continue to have an increase in urban land, leading to an augmented vulnerability of coastal erosion processes brought by the loss of forest areas which protect from erosion given the root system that directly protects from the existing wave energy and helps sedimentation processes. The above methodology and the availability of data that are freely available render such a combined approach interesting for many other regions of the world, where tourism, coastal change and regional balance are of the utmost importance for sustainable development. The advanced research tools presented here are of critical importance for coastal zone degradation management.  相似文献   
69.
Luminance distribution in the visual field is considered as one of causal factors with a significant influence on visual fatigue, especially for intensive and extended Video Display Terminal (VDT) work. The aim of the study was to define visual fatigue of VDT operators for different values of surrounding luminance. Experiments were carried out in laboratory conditions under 3 lighting conditions. Only 1 lighting parameter—the luminance of the wall behind the display (surrounding luminance)—changed. Visual fatigue was measured both by a subjective evaluation of different visual complaints (asthenopic symptoms) and by objective measurements of changes in the following visual functions: accommodation, convergence, habitual horizontal phoria, critical fusional frequency (CFF), and visual acuity. The same experiments were done for CRT (Cathode Ray Tube) and LCD TFT (Liquid Crystal Display with Thin Film Transistor) screens. The results of the study have shown that there was no significant influence of the value of surrounding luminance on the asthenopic symptoms for either type of screen. A general tendency towards bigger visual complaints for LCD TFT than for CRT participants was found. An objective evaluation of visual fatigue demonstrated a tendency towards bigger changes in visual functions with an increase of surrounding luminance for both screens. Statistical analysis of the results has shown that surrounding luminance influences significantly the reduction of the accommodation amplitude (significance level < .05).  相似文献   
70.
The second part of the article presents the results of a study of antimicrobial activity of filter nonwovens with an addition of biocides, as a function of the presence of sweat in the environment and the method of microbe deposition on a nonwoven in the form of a liquid and a bioaerosol. At the same time, the filtration efficiency of nonwovens against microorganisms in the form of a bioaerosol was tested with the dynamic method. The results showed that the addition of sweat on the surface of a nonwoven resulted in an insignificant decrease of biological activity that still remained high. Moreover, an active nonwoven showed biostatic and biocidal activity only when microbes were deposited on the surface in the form of a solution. The nonwoven did not show any biological activity after deposition of microorganisms with the dynamical method in the form of a bioaerosol.  相似文献   
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