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61.
Ewa Kłodzińska Wojciech Kupczyk Marek Jackowski Boguslaw Buszewski 《Electrophoresis》2013,34(22-23):3206-3213
A surgical site infection (SSI) is an infection that occurs after surgery in the part of the body where the surgery took place. An SSI may range from a spontaneously limited wound discharge within 7–10 days of an operation to a life‐threatening postoperative complication, such as a sternal infection after open heart surgery. Most SSIs are caused by contamination of an incision with microorganisms from the patient's own body during surgery. From the analytical point of view, the complex nature of these samples as well as the low concentrations of analytes require a system with high sensitivity and efficiency. Such situation requires a technique such as CE, which is a powerful and versatile separation technique that promises to rival HPLC when applied to the separation of both charged and neutral species. During the study, it has been demonstrated that CZE identifies characteristics of such groups of pathogens such as bacteria Gram (+) and different species of bacteria Gram (?), and also develops weekly individual profiles for patients after application of antibiotics. This was done in order to show the impact of antibiotic therapy in change “numbers” of bacteria present in the wound after surgery. The method proved to be the ideal straight specificity in the case of Escherichia coli (100%). Finally, analysis of the spectra and the second derivatives of the UV‐Vis spectra confirmed the similarity in the profiles and showed that the CZE is a great method for fast screening test in bacterial infection. 相似文献
62.
Błażej Gierczyk Wojciech Ostrowski Marcin Kaźmierczak 《Magnetic resonance in chemistry : MRC》2012,50(4):271-277
2‐Aryl‐1,3,4‐selenadiazoles were studied by 1H, 13C, 15N and 77Se NMR spectroscopy. The results (chemical shifts and coupling constants) were correlated with Hammett substituent parameters as well as calculated chemical shifts and bond lengths. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
63.
Wojciech Kucharz 《Mathematische Zeitschrift》2016,283(3-4):1201-1215
64.
The effects of a semi-transparent reacting particle irradiation are analysed using a transient combined heat transfer model. Direct uniform irradiation is found to be favourable for particle heating and decomposition, decreasing the total reaction time by a factor of 3.3 as compared to that for non-uniform irradiation. In both cases heat transfer from the surface to the reaction zone is the process limiting mechanism. 相似文献
65.
66.
Krzysztof Garman Ewa Olewnik Wojciech Czerwiński 《Journal of Thermal Analysis and Calorimetry》2013,111(1):799-805
This article presents the results of investigation into receiving amide modification agents of smectic clays, used as nanofillers in polymer nanocomposites. Prepared materials were obtained on the base of terephthalic and isophthalic acids and simple aliphatic amines. Such structure makes them good layered silicates modifying agents as well as makes them well affiliate to structure of polymers containing aromatic, carbonyl, amide, etc. groups. Obtained compounds were introduced into clays’ structure in protonated form, according to formulated method. Conducted research confirmed that the modification of montmorillonite clay (MMT) with received compounds had taken place. In order to establish that fact elementary analysis and X-ray diffraction (XRD) methods were used. Modificator molecules must display thermal resistance in full range of polymer processing temperatures. To investigate these properties the Thermogravimetric analysis (TG) of obtained compounds was carried out. These studies indicate that among the obtained compounds there were the ones with thermal stability over 523 K. Thermal resistance makes it possible for these substances to be used in poly(ethylene terephthalate) processing. 相似文献
67.
Van der Waals equation of state as well as power laws and critical exponent theories are prototypes to study the cubic shape, asymmetries and “flatness” of the vapor–liquid equilibrium curves near the critical point. In this work we study two similar methods to determine the phase curves in analytical form, which differ from each other by simplicity of mathematical calculation. We analyze temperature dependence of the coexistence curves asymptotically close to the vapor–liquid critical point. We explain the novelty of our method with respect to the standard thermodynamic limit discussed in the literature. Therefore we show that the shape of the coexistence curves can strongly influence the accepted value of the critical exponent. The results of theoretical studies have been compared with the ones obtained by experimental methods. 相似文献
68.
Monika Szufla Aleksandra Choroś Dr. Wojciech Nitek Prof. Dariusz Matoga 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(37):e202200835
By using the strategy of pre-assembly chlorosulfonation applied to a linker precursor, the first sulfonated zirconium metal–organic framework ( JUK-14 ) with two-dimensional (2D) structure, was synthesized. Single-crystal X-ray diffraction reveals that the material is built of Zr6O4(OH)4(COO)8 oxoclusters, doubly 4-connected by angular dicarboxylates, and stacked in layers spaced 1.5 nm apart by the presence of sulfonic groups. JUK-14 exhibits excellent hydrothermal stability, permanent porosity confirmed by gas adsorption studies, and shows high (>10−4 S/cm) and low (<10−8 S/cm) proton conductivity under humidified and anhydrous conditions, respectively. Post-synthesis inclusion of imidazole improves the overall conductivity increasing it to 1.7×10−3 S/cm at 60 °C and 90 % relative humidity, and by 3 orders of magnitude at 160 °C. The combination of 2D porous nature with robustness of zirconium MOFs offers new opportunities for exploration of the material towards energy and environmental applications. 相似文献
69.
70.
Łukasz Płociniczak Wojciech Okrasiński Juan J. Nieto Oscar Domínguez 《Journal of Mathematical Analysis and Applications》2014
In this paper we present some results concerning a boundary value problem for a nonlinear ordinary differential equation that was used before in modeling the topography of human cornea. These results generalize previously obtained theorems on existence and uniqueness. We show that our equation has a unique solution for all parameters and conditions that can arise in physical situation. In the second part of the article we derive some new estimates and approximate solutions. Numerical calculations verify that these approximations are very accurate. 相似文献