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In the present work, the possibility of using isotachophoresis (ITP) as an alternative method for the continuous control of sewage treatment plant efficiency is presented. The performed experiments focused on the nitrification process products as well as the determination of heavy metal concentration in raw sewage. Total concentration of nitrates and heavy metals is analysed in the sewage samples, ranging from 50 to 120mg/L and 0 to 1.9mg/L, respectively. The analytical error (below 10%), the analysis time (shorter then 50 minutes for heavy metals, and 12 minutes for nitrates) and the general analytical performance are better from those obtained by atomic absorption spectrometry (AAS) and ion selective electrode (ISE).  相似文献   
2.
In this study, selective methods were developed for isolation, purification, separation and determination of 4-nonylphenol (4NP) in biological samples. Several methods such as high-performance liquid chromatography (HPLC) with fluorescence and diode array detection and gas chromatography coupled to mass spectromotry (GC-MS) are described for the simultaneous determination of 4NP. The nonylphenols in the plasma of fish were extracted through solid phase process by using octadecyl, polymeric and octadecyl endcapping sorbents. The average recoveries in plasma samples spiked with 4NP of levels 1?µg?mL?1 were between 80–95% using added surrogate standards. The aim of this study was to determine whether trace amounts of 4NP in fish plasma samples could be detected by solid phase extraction and chromatographic methods (HPLC, GC-MS). This technique of monitoring the levels of endocrine-disruptors in plasma samples is consistent, reliable as well as inexpensive.  相似文献   
3.
There is a dearth of data on the consumer product concentrations of iron, lead, and nickel for accurate comparison to be made. The levels of these elements were determined in 85 samples of six different classes of personal care products commonly used in Nigeria using atomic absorption spectrophotometry. The results of the analysis showed that the range of the mean concentrations of Fe was 0.485–1.108 ppm, Pb ND–0.163 ppm, and Ni ND-0.160 ppm. The analytical data have demonstrated that the selected consumer products are possible sources of iron, lead, and nickel exposure. Users can be exposed to these metals directly through dermal contact or inhalation. The regulations relating to cosmetic products give no limit values for heavy metals in cosmetic products, hence, it was difficult to establish if the values obtained in this study are safe or not. Prolonged use of soaps, creams, and detergent containing these elements may pose threat to human health and the environment. This could be responsible for various skin diseases such as allergic skin, follicular and pigmentary disorders, which are common among the users (exposed groups) of these products in Nigeria. A body of evidence has presented a rare example of systemic allergic dermatitis caused by topical application of a mercury-containing cosmetic to the upper lip of a 32-year-old Turkish patient.  相似文献   
4.
Insect pollination and pollen feeding can reduce plant volatile emissions and future insect floral attraction, with oviposition having different effects. Meligethes aeneus F. (Coleoptera: Nitidulidae), is a pollen-feeding pest beetle of oilseed rape, Brassica napus L. (Brassicaceae). We measured plant VOC emission over 72 h from two types of 24 h M. aeneus exposure to B. napus: pollen feeding vs. flower bud injury and oviposition. The most abundant constitutive volatile organic compounds (VOCs), lilac aldehydes A (LA A) & B (LA B) and veratrole (VER), had 30–40 % reductions from M. aeneus pollen-feeding exposure at 24 h and 50–90 % reductions by 72 h, with greater reductions after bud injury and oviposition. Linalool (LIN), a common herbivore-induced plant volatile (HIPV), emission did not change at 24 h, but was induced six- to sevenfold 48 h after both exposure treatments. By 72 h, LIN had even greater (tenfold) induction after bud injury and oviposition, but no induction from pollen feeding. Three common HIPVs (β-caryophyllene, = βCAR (E)-β-farnesene = EβFAR, and (Z)-β-ocimene = ZβOCI) were progressively induced up to 2.5-fold 72 h after floral bud injury and oviposition. We assayed M. aeneus adult behavioral responses to LA A and B, and VER. Both M. aeneus sexes were attracted to higher concentrations than single plant constitutive emission for these VOCs, but avoided much higher doses. Progressive LA A and B, and VER, emission reductions might help plants (e.g., B. napus) to avoid future interactions with pollen-feeding pest herbivores (e.g., M. aeneus). After bud injury and oviposition, HIPV induction could help plants deter future oviposition and/or attract natural enemies to deposited eggs.  相似文献   
5.
This review paper describes the state of the Vistula basin and the Baltic Sea area. The article is divided into two parts concerning the river and the Baltic coastal zone, respectively. Each part describes the geography and the environmental state of the region and gives an overview of the socio-economic conditions. The environmental state of the study regions is described in terms of annual monitoring data for the main physico-chemical and biological parameters. The data cover the last decade. The socio-economic overview includes parameters such as e.g. population density, industrialization, agricultureand land use.SI: Pirrone  相似文献   
6.
Sewage sludge is a serious problem facing modern wastewater treatment plants. One of the methods to safely utilize the sludge is through composting and the agricultural use of the final product.In this study the compost samples from municipal sewage sludge are compared to the natural, rich in organic matter samples. Based on physicochemical properties of the material, the maturity indices are obtained to evaluate the quality of organic matter and estimate the similarities between the samples.The study shows that one-dimensional analysis like that based on maturity indices does not provide satisfactory answers concerning the nature of such complex materials. The data set of the analysis naturally possesses a multidimensional character so that the employment of advanced chemometric techniques like cluster analysis show a number of features which were hidden within the ‘data flood’.The major conclusion of this work is that the compost from sewage sludge is similar to peat in the significance of the properties of the organic matter. Moreover, the organic matter of agricultural soil, which is most stable and has been naturally matured over a long period of time, differs substantially from the other samples.  相似文献   
7.
Comparative investigations of the sorption process of gaseous toluene were performed using fruit material (orange peel) and the mixture of chemically bonded phases (CBPs) as sorbents. For this study, a specially constructed system that allows exposure of sorbents to volatile air contaminants at constant concentrations was applied. The results for the prepared packings indicate a typical adsorption process described by Langmuir isotherm. In the case of orange peel, a mixed mechanism of the sorption process is suggested.  相似文献   
8.
Investigations were carried out in the Department of Conservation of Painting and Polychrome Sculpture and in the Screen Printing Studio of the Faculty of Art at Nicolaus Copernicus University. Concentration of the vapours of organic solvents was measured in 2 workshops: the Art Conservation Studio and the Screen Printing Studio. This study attempts to evaluate the work environment in both studios by analysing the concentration of vapour solvents over 5 to 7 years of measurements. Volatile solvents--aliphatic and aromatic hydrocarbons, alcohols, esters and ketones--were detected in investigated workplaces. These compounds have a wide range of applications in cleaning and removing old varnishes, lacquers and paints; inhalation is the main route of exposure. Vapour was collected using an active sampling method.  相似文献   
9.
Study of sorption kinetics of some ionic liquids on different soil types   总被引:1,自引:0,他引:1  
In the present contribution sorption kinetics experiments under static conditions were utilized in three selected ionic liquids cations (1-ethyl-3-methylimidazolium, 1-butyl-3-methylimidazolium, 1-hexyl-3-methylimidazolium chlorides) study with five type of soil, differing in total organic carbon (TOC) content. The experimental results indicate the sorption capacity growth with increase in TOC content and hydrophobicity of ionic liquid cation. The obtained kinetic sorption parameters as well as distribution coefficients (Kd) were used to estimate the sorption properties of the soil types towards the ionic liquids in question. The Gibbs free energy values indicate that ionic liquid cations sorption on soils could be generally considered as a physical adsorption with exothermic effect. But the values of −dG for studied cations sorption on soil with very high of TOC content in soil (45%) may testify to nature of chemical adsorption. Sorption of the analyzed compounds occurs probably by means of hydrogen bonds, electrostatic and π  π interaction with the organic matter and the clay minerals of the soils.  相似文献   
10.
The laboratory experiments were carried out to study the sorption process of gaseous toluene in the peel of different fruits as well as in the chemically prepared material based on silica support (multiligand-adsorbent). For the sorption experiments, a vapor generating system was used that allows the exposure of sorbents to a constant flux of polluted air. The concentration of toluene in the tested sorbents was followed as a function of exposure time. The obtained results were correlated to the mathematical models describing the sorption kinetics in the leaves. The investigation with the plant material showed dual-phase behavior of the toluene partition ('mixed' sorption mechanism), in the case of multiligand-adsorbent a typical adsorption process was observed. Sorption kinetics to fruit material was well correlated to the two-compartment model, while for the chemically prepared material to the first-order model.  相似文献   
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