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81.
Valentina Ljubomirova Rumyana Djingova Johannes T. van Elteren Marjan Veber Tomasz Kowalkowski Boguslaw Buszewski 《International journal of environmental analytical chemistry》2013,93(7):499-512
A sequential extraction procedure (three-step), proposed by the Standards, Measurements and Testing Programme (formerly BCR) of the European Union, was applied to street dust and spiked soil samples for the determination of PGEs. Analyses were carried out using inductively coupled plasma-mass spectrometry (ICP-MS). The results indicate that up to 5% from Pt, 70% from Pd and 14% from Rh are in mobile forms in street dust. The results for the soil samples spiked with crushed catalytic converter are significantly lower indicating that PGEs are oxidised more efficiently in natural conditions. Additionally Pt and Pd bound to humic acids were investigated. 相似文献
82.
Tomasz Kowalkowski Hlanganani Tutu Leonard Mihaly Cozmuta Miroslav Sprynskyy Ewa M. Cukrowska Bogusław Buszewski 《International journal of environmental analytical chemistry》2013,93(10):797-811
The objectives of this study were to evaluate the mobility of heavy metals (HMs) in two types of soils (acidic forest soil and neutral agricultural soil) by leaching with calcium chloride solution in column experiments. The screening properties of neutral agricultural soil towards pollution by heavy metals (Ni, Cu, Zn and Cd) are approximately 10 times higher than those of acid forest soil. The neutral agricultural soil, polluted artificially by one pore volume (PV) of an HMs solution of concentration 200 mg L?1, can screen the leaching of these metals over several hundreds of years. The higher apparent desorption rate and per cent desorption of HMs (especially Cd) in acid forest soil indicated a higher potential of intensive migration of the metals across the profile and indicated potential risk of Cd pollution for this type of soil. The latest approach of artificial neural networks to describe transport of HMs in soil has been also evaluated. Using a simple three-layer perceptron topology with three hidden neurons, the experimental data could be simulated. The results suggested that the pH of soil is a major factor controlling the retention of the heavy metals in the soils. 相似文献
83.
Tomasz Girek 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(3-4):237-252
In the paper cyclodextrin-based (CD) polyrotaxanes are presented in the aspect of their syntheses and properties allowing various applications. The text consists of four parts, which describe CD-based polyrotaxanes with threads containing poly(ethylene oxide), poly (4,4′-diphenylenevinylene), polyfluorene and other chains. Conclusion shows new trends connected with this theme. 相似文献
84.
85.
Tomasz Schoen 《Combinatorica》2015,35(6):695-701
We prove, in particular, that every finite subset A of an abelian group with the additive energy κ|A|3 contains a set A′ such that |A′|?κ|A| and |A′ ? A′|?κ ?4|A′|. 相似文献
86.
87.
Tomasz Chmiel Dionna Abogado Waldemar Wardencki 《Analytical and bioanalytical chemistry》2014,406(20):4965-4986
A reliable and repeatable isotachophoretic method for the simultaneous determination of K+, Na+, Ca2+, Mg2+, and ammonium in berries of different blue honeysuckle cultivars was developed. The usefulness of the complex-forming equilibria in determining the cations mentioned above was studied. The addition of 7.5 mM 18-crown-6 and 2 mM α-hydroxyisobutyric acid to sulfuric acid enhanced the separation capacity of the leading electrolyte. The terminating electrolyte of 10 mM TRIS buffered to pH 4.30 was chosen as most appropriate for these studies. An ultrasound-assisted procedure for the extraction of macroelements from dried fruit of Lonicera caerulea L. was investigated using response surface methodology. The Box-Behnken experimental design showed the optimal extraction conditions as follows: temperature of 36 °C, extraction time of 42.3 min and solid-to-liquid ratio of 1:800 v/w. Detection limits for the method ranged from 0.030 to 0.097 mg/l with precision expressed by RSD ranging from 1.4 % for Mg to 4.4 % for Na. The results showed that blue honeysuckle berries are a good source of potassium, from 199 to 402 mg/100 g FW, especially ‘Zielona’ and ‘Zojka’ cultivars. The average content of other analytes in these berries was 5.2 mg Na, 24.8 mg Ca, 7.5 mg Mg and 52.0 mg ammonium per 100 g FW. The berry products contained lower amounts of minerals especially Mg and K. However, a glass of freshly squeezed juice can provide almost 20 % of the RDI of potassium. The results obtained using both the developed isotachophoretic method and ion chromatographic procedure did not differ significantly. Figure
? 相似文献
88.
The paper deals with a methodology of shaping the vibro-isolation properties of suspensions applied in automotive systems. The developed optimisation procedure allows to find the Pareto-optimal system configuration for the conflicted vibro-isolating criteria. The correctness of proposed methodology is evaluated using the semi active and active systems with optimal controller settings. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
89.
Janovszky Dora Sveda Maria Sycheva Anna Kristaly Ferenc Zámborszky Ferenc Koziel Tomasz Bala Piotr Czel Gyorgy Kaptay George 《Journal of Thermal Analysis and Calorimetry》2022,147(13):7141-7157
Journal of Thermal Analysis and Calorimetry - A remarkable number of scientific papers are available in the literature about the bulk amorphous alloys and metallic glasses. Today, DSC is an... 相似文献
90.
Izabela Gregorczyk Agnieszka Jasiecka-Mikoajczyk Tomasz Malanka 《Molecules (Basel, Switzerland)》2021,26(11)
The main purpose of this study was to investigate whether the blockade of the interaction between the receptor activator of nuclear factor-κB (NF-ĸB) ligand (RANKL) and its receptor RANK as well as the blockade of NF-κB inhibitor kinase (IKK) and of NF-κB translocation have the potential to suppress the pathogenesis of allergic asthma by inhibition and/or enhancement of the production by CD4+ and CD8+ T cells of important cytokines promoting (i.e., IL-4 and IL-17) and/or inhibiting (i.e., IL-10 and TGF-β), respectively, the development of allergic asthma. Studies using ovalbumin(OVA)-immunized mice have demonstrated that all the tested therapeutic strategies prevented the OVA-induced increase in the absolute number of IL-4- and IL-17-producing CD4+ T cells (i.e., Th2 and Th17 cells, respectively) indirectly, i.e., through the inhibition of the clonal expansion of these cells in the mediastinal lymph nodes. Additionally, the blockade of NF-κB translocation and RANKL/RANK interaction, but not IKK, prevented the OVA-induced increase in the percentage of IL-4-, IL-10- and IL-17-producing CD4+ T cells. These latter results strongly suggest that both therapeutic strategies can directly decrease IL-4 and IL-17 production by Th2 and Th17 cells, respectively. This action may constitute an important mechanism underlying the anti-asthmatic effect induced by the blockade of NF-κB translocation and of RANKL/RANK interaction. Thus, in this context, both these therapeutic strategies seem to have an advantage over the blockade of IKK. None of the tested therapeutic strategies increased both the absolute number and frequency of IL-10- and TGF-β-producing Treg cells, and hence they lacked the potential to inhibit the development of the disease via this mechanism. 相似文献