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151.
Various types of carbon nanoparticles were directly mixed with microbial cells of Gluconobacter oxydans within a 3-D bionanocomposite in order to prepare a highly sensitive ethanol biosensor with a short response time. From all carbonaceous nanomaterials tested, single- or multi-walled carbon nanotubes provided the highest sensitivity of detection (117–121 µA cm?2 mM?1), but from a practical point of view, Ketjen black 300 and 600 provide very low detection limit (2–6 µM) and high sensitivity for the ethanol analysis (84–88 µA cm?2 mM?1)with a shortresponse time (14–33 s). Moreover, the price of Ketjen black is a few orders of magnitude lower compared to that of carbon nanotubes. Finally, the study showed that the morphology of nanoparticles rather than their surface modification is the key element in achieving high sensitivity of ethanol detection. 相似文献
152.
Špírková Milena Kredatusová Jana Hodan Jiří 《Journal of Thermal Analysis and Calorimetry》2017,128(3):1699-1709
Journal of Thermal Analysis and Calorimetry - Thermal stabilities of all-aliphatic thermoplastic polyurethane (PU) films, either three-component (made from polycarbonate-based macrodiol,... 相似文献
153.
František Kačík Jana Luptáková Pavel Šmíra Adriana Eštoková Danica Kačíková Andrea Nasswettrová Tatiana Bubeníková 《Journal of Thermal Analysis and Calorimetry》2017,128(2):755-764
Glasses having composition 5Li2O–5ZnO– xBi2O3 –(90 ? x) P2O5 (x = 5, 10, 15, 20 and 25 mol%) were prepared by the normal melt quenching technique. Nanocomposite glass containing bismuth phosphate BiPO4 nanocrystals was obtained, which can be attributed to homogeneous nucleation process. The formation of BiPO4 nanocrystals was confirmed and characterized by X-ray diffraction patterns (XRD), transmission electron microscopy (TEM), differential scanning calorimetry, optical absorption (UV–Vis) and micro-hardness studies. The morphological analysis by XRD and TEM microscopy showed the formation of hexagonal BiPO4 nanocrystals, and its estimated nanocrystalline sizes were found to be varying from 5.35 to 11.53 nm depending on the Bi2O3 concentrations. The density (ρ) and molar volume (V m) were also determined and found to be in compositional dependence. Glass transition temperature (T g) and glass crystallization temperature (T c) were obtained and found to be increased (from 240.0 to 337.2 °C) with increasing Bi2O3 up to 20 mol% and then decreased (from 337.2 to 331.8 °C) due to the structural changes in the glass network. Effect of BiPO4 content on the optical properties had been investigated. From the UV–Vis spectra, it was observed that the fundamental absorption edge shifts toward lower wavelengths, i.e., blueshifts with increasing Bi2O3 mol% up to 20 mol%, and then shifts toward higher wavelengths, i.e., redshifts beyond 20 mol%. It was also observed that the obtained E opt (for indirect and direct transitions) increases with gradual increase in Bi2O3 content up to 20 mol% and then decreases beyond 20 mol%. This may be due to the introduction of Bi cations into the glass network as a network former up to 20 mol% causing a decrease in ΔE values, beyond 20 mol%, the introduction of Bi ions into the glass network interstitially leads to increase the values of ΔE. The optical properties of the present nanocrystallized glasses showed a quantum size dependence, in which the optical band gap energy (E opt) was changed as a function of BiPO4 nanocrystalline sizes. 相似文献
154.
Dr. Samuel M. Meier M. Sc. Dominique Kreutz Dr. Lilli Winter M. Sc. Matthias H. M. Klose M. Sc. Klaudia Cseh M. Sc. Tamara Weiss Dr. Andrea Bileck M. Sc. Beatrix Alte Dr. Johanna C. Mader M. Sc. Samir Jana Dr. Annesha Chatterjee Dr. Arindam Bhattacharyya Michaela Hejl Dr. Michael A. Jakupec Priv.-Doz. Dr. Petra Heffeter Prof. Dr. Walter Berger Prof. Dr. Christian G. Hartinger Prof. Dr. Bernhard K. Keppler Prof. Dr. Gerhard Wiche Prof. Dr. Christopher Gerner 《Angewandte Chemie (International ed. in English)》2017,56(28):8267-8271
Organometallic metal(arene) anticancer agents require ligand exchange for their anticancer activity and this is generally believed to confer low selectivity for potential cellular targets. However, using an integrated proteomics-based target-response profiling approach as a potent hypothesis-generating procedure, we found an unexpected target selectivity of a ruthenium(arene) pyridinecarbothioamide (plecstatin) for plectin, a scaffold protein and cytolinker, which was validated in a plectin knock-out model in vitro. Plectin targeting shows potential as a strategy to inhibit tumor invasiveness as shown in cultured tumor spheroids while oral administration of plecstatin-1 to mice reduces tumor growth more efficiently in the invasive B16 melanoma than in the CT26 colon tumor model. 相似文献
155.
The aim of the paper is to highlight the necessity of applying the concept of constrained fuzzy arithmetic instead of the concept of standard fuzzy arithmetic in a fuzzy extension of Analytic Hierarchy Process (AHP). Emphasis is put on preserving the reciprocity of pairwise comparisons during the computations. For deriving fuzzy weights from a fuzzy pairwise comparison matrix, we consider a fuzzy extension of the geometric mean method and simplify the formulas proposed by Enea and Piazza (Fuzzy Optim Decis Mak 3:39–62, 2004). As for the computation of the overall fuzzy weights of alternatives, we reveal the inappropriateness of applying the concept of standard fuzzy arithmetic and propose the proper formulas where the interactions among the fuzzy weights are taken into account. The advantage of our approach is elimination of the false increase of uncertainty of the overall fuzzy weights. Finally, we advocate the validity of the proposed fuzzy extension of AHP; we show by an illustrative example that by neglecting the information about uncertainty of intensity of preferences we lose an important part of knowledge about the decision making problem which can cause the change in ordering of alternatives. 相似文献
156.
Sharvari Deshmukh Kalyani Kamde Arun Jana Sanjivani Korde Rajib Bandyopadhyay Ravi Sankar Nabarun Bhattacharyya R.A. Pandey 《Analytica chimica acta》2014
Electronic nose systems when deployed in network mesh can effectively provide a low budget and onsite solution for the industrial obnoxious gaseous measurement. For accurate and identical prediction capability by all the electronic nose systems, a reliable calibration transfer model needs to be implemented in order to overcome the inherent sensor array variability. In this work, robust regression (RR) is used for calibration transfer between two electronic nose systems using a Box–Behnken (BB) design. Out of the two electronic nose systems, one was trained using industrial gas samples by four artificial neural network models, for the measurement of obnoxious odours emitted from pulp and paper industries. The emissions constitute mainly of hydrogen sulphide (H2S), methyl mercaptan (MM), dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) in different proportions. A Box–Behnken design consisting of 27 experiment sets based on synthetic gas combinations of H2S, MM, DMS and DMDS, were conducted for calibration transfer between two identical electronic nose systems. Identical sensors on both the systems were mapped and the prediction models developed using ANN were then transferred to the second system using BB–RR methodology. The results showed successful transmission of prediction models developed for one system to other system, with the mean absolute error between the actual and predicted concentration of analytes in mg L−1 after calibration transfer (on second system) being 0.076, 0.1801, 0.0329, 0.427 for DMS, DMDS, MM, H2S respectively. 相似文献
157.
Utilization of Slovak bentonites in deposition of high-level radioactive waste and spent nuclear fuel 总被引:2,自引:0,他引:2
Michal Galambo? Ol��ga Rosskopfov�� Jana Kuf?��kov�� Pavol Rajec 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(3):765-777
The basic strategic aims in the field of managing high-level radioactive waste and liquidation of nuclear power plants are all contained in the Energy policy of the Slovak Republic. Its aim is to resolve the concept of the backside of the nuclear energetics fuel cycle??long-term deposition of high-level radioactive waste and spent nuclear fuel (SNF). The most important form of high-level radioactive waste and SNF long-term deposition is their deposition in deep geological formations created by natural as well as engineering barriers used to isolate the long-lived radionuclides from the biosphere. The basic components of these barriers are clays, of which bentonite is generally referred to as the most suitable clay material. There are a few significant bentonite deposits in the Slovak Republic: Jel?ový potok, Kopernica, Lastovce, Lieskovec, Dolná Ves. The review article summarizes the information on geotechnical properties of Slovak bentonites published up-to-date, which is inevitable to know for the intention of their use. It highlights the advantages and shows drawbacks of five Slovak deposits. It suggests further research direction, to draw a thorough hydraulical, microbial and radiation profile of Slovak bentonites. 相似文献
158.
Kvasnička F Copíková J Sevčík R Václavíková E Synytsya A Vaculová K Voldřich M 《Electrophoresis》2011,32(9):1090-1093
Phytic acid (PA) and lower inositolphosphates (InsP(n) ) is the main storage form of phosphorus in grains or seeds. The content of PA and InsP(n) in different varieties of barley was analyzed by capillary isotachophoresis and online-coupled capillary isotachophoresis with CZE. The electrolytes (in demineralized water) for the isotachophoretic analysis consisted of 10?mM HCl, 14?mM glycylglycine, and 0.1% 2-hydroxyethylcellulose (leading) and 10?mM citric acid (terminating). The optimized electrolytes for the online coupling isotachophoresis with zone electrophoresis analysis were mixtures of 5?mM HCl, 7?mM glycylglycine, and 0.1% 2-hydroxyethylcellulose (leading), 20?mM citric acid, 10?mM glycylglycine, and 0.1% 2-hydroxyethylcellulose (background) and 10?mM citric acid (terminating). PA and all studied InsP(n) were separated within 25?min and detected by a conductivity detector. Simple sample preparation (acidic extraction), sufficient sensitivity, speed of analysis, and low running cost are important attributes of the electrophoretic methods. The method was used for the determination of PA and InsP(n) in barley varieties within an ongoing research project. 相似文献
159.
In this study, ionic liquids (ILs) as BGE additives were applied for the analysis of neutral carbohydrates in CE. The ILs served primarily as chromophores for indirect UV detection. The influence of imidazolium-based ionic liquids on the separation, detection limits and mobility of underivatized neutral carbohydrates was investigated. BGEs consisting of 10-50 mM of ILs at pH 12.4 without other additives provided fast separation of neutral sugars. This method was used to determine sucrose, glucose and fructose in certain vegetable juices. 相似文献
160.
The method for determination of rate constants of interconversion of enantiomers in chiral and achiral environments of a dynamic enantioseparation system was investigated in order to reveal its accuracy, sensitivity and robustness. Two significantly different enantioseparation systems were selected, one with a single (well-defined) chiral selector (CS) and the second with a mixture of CSs, and the rate constants of interconversion for these two systems were compared statistically. While the rate constants of interconversion in the chiral environment were found to be significantly different, the rate constants in achiral environment were confirmed to be statistically the same. The accuracy of the method was independent of experimental conditions. Influence of a CS and temperature on the rate of interconversion were discussed within the scope of determined thermodynamic parameters and statistical evaluation. A certain temperature may exist at which two different types of CSs influence the rate of interconversion equally while the extent of their influence may largely differ at other temperatures. 相似文献