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51.
Conventional fuels used for supplying internal combustion piston engines include petrols and diesel oils produced from petroleum. These are a non-renewable energy source. The environmental policy of the European Union is geared towards increasing the share of renewable fuels in the overall energy consumption. An alternative fuel originating from a renewable source, which could be used for feeding self-ignition internal combustion engines are the fatty acid methyl esters (FAME) of plant oils. The paper reports selected results of testing a 1.3 MULTIJET SDE 90 PS self-ignition engine with the Common Rail reservoir feed system supplied with mixtures of diesel oil and rape oil fatty acid methyl esters (FAME). Tests were carried out on an engine test bed equipped with an eddy-current brake. The purpose of the tests was to determine the economic–energy and ecological indices of engine operation. The concentrations of exhaust gas gaseous components were measured using a MEXA-1600DEGR analyzer, while the particulate concentrations, with a MEXA-1230PM analyzer. In addition, the variations of working medium pressures in the engine chamber and of fuel pressure upstream the injector were recorded as a function of crankshaft rotation angle using the AVL IndiSmart 612 indication system for this purpose. The physicochemical properties of fuels used in the tests were determined using a fuel analyzer. The obtained testing results made it possible to determine and assess the operation indices of the engine fed with mixtures of diesel oil and rape oil fatty acid methyl esters (FAME) with slightly higher ester contents than the requirements of the currently applicable diesel oil standard. 相似文献
52.
In this work, we aim at quantifying quantum channel output similarity. In order to achieve this, we introduce the notion of quantum channel superfidelity, which gives us an upper bound on the quantum channel fidelity. This quantity is expressed in a clear form using the Kraus representation of a quantum channel. As examples, we show potential applications of this quantity in the quantum control field. 相似文献
53.
Julia Radwan-Pragłowska Marek Piątkowski Diana Kitala Łukasz Janus Agnieszka Klama-Baryła Wojciech Łabuś 《国际聚合物材料杂志》2019,68(7):351-359
In this work we present a novel strategy for chitosan-based scaffolds. Chitosan is a versatile biopolymer obtained from waste biomass known of its favorable biological properties. Thus it can replace other polymers in the preparation of bioactive scaffolds. To increase its durability chitosan can be crosslinked into form of the hydrogel yet application of toxic crosslinkers may lead to loss of biocompability. Mesenchymal stem cells can be used in cell therapy for advanced wound treatment. However their culture requires special biomaterials application. In this article a novel microwave-assisted synthesis method for bioactive chitosan scaffolds is presented. 相似文献
54.
Świć Antoni Gola Arkadiusz Sobaszek Łukasz Šmidová Natalia 《Journal of Intelligent Manufacturing》2021,32(7):1939-1951
Journal of Intelligent Manufacturing - The article presents a new thermo-mechanical machining method for the manufacture of long low-rigidity shafts which combines straightening and heat treatment... 相似文献
55.
E. RAFAJŁOWICZ 《International journal of systems science》2013,44(9):1513-1520
The problem of non-parametric identification of a static system is considered in the presence of errors both in dependent and independent variables. Identification is based on the orthogonal series expansion. Errors in independent variables are modelled in two ways, namely as pointwise errors and as errors caused by an averaging. Sufficient conditions for MISE consistency are proved in both cases. 相似文献
56.
Łukasz Szabłowski Jarosław Milewski Krzysztof Badyda Jakub Kupecki 《International Journal of Hydrogen Energy》2018,43(6):3555-3565
The idea of control strategy of SOFC operating to meet demand of a public utility building was presented. The strategy was formulated with the support of Artificial Neural Network. The network was used to predict the demand for electricity. The calculations were carried out on the example of a building of the Institute of Heat Engineering Warsaw University of Technology. The control strategy is influenced by various factors depending on changes in market conditions and operating characteristics of the cell. We can define different objective functions eg: working for own needs, for maximum profit and maximum service life. The article presents a simulation of SOFC operation for demand profile of the IHE building from the selected time period. 相似文献
57.
Sour cherry (Prunus cerasus) is rich in biologically active phenolic compounds. These compounds are concentrated in fruit skin and most of them remain in the leftovers during the production of juice. Supercritical carbon dioxide extraction was used to separate phenolic compounds from sour cherry pomace. The effects of temperature, pressure and the addition of ethanol on anthocyanin and the total phenolic content and radical scavenging activity of the extracts were investigated. The best results were acquired for 35°C, 10 MPa and 80% ethanol addition. A strong correlation was found between the phenolic content and other features of the extracts. 相似文献
58.
Assessment of the hydromorphological state of Carpathian rivers above and below reservoirs
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The article presents the results of an assessment of the hydromorphological state of selected Carpathian rivers in sections above and below the reservoirs. An attempt has also been made to assess the impact of reservoirs on the hydromorphological conditions and quality of river habitats. The research was based on the River Habitat Survey (RHS) method. The synthetic indices Habitat Quality Assessment (HQA) and Habitat Modification Score (HMS) were calculated on the basis of the gathered data for each section studied; this allowed the hydromorphological qualities of the rivers to be assessed numerically. The reservoirs interrupt river continuum, and they alter different biotic and abiotic elements of natural environment. However, this study has shown that the operation of reservoirs does not always negatively impact the hydromorphological conditions of rivers that reflect their habitat quality. The influence of reservoirs on a river's hydromorphological state above and below a reservoir's location may be neutral, but it also can improve the habitat conditions of a river. 相似文献
59.
Synthesis of Novel Phosphonic‐Type Activity‐Based Probes for Neutrophil Serine Proteases and Their Application in Spleen Lysates of Different Organisms
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Dr. Renata Grzywa Dr. Ewa Burchacka Maria Łęcka Dr. Łukasz Winiarski Maciej Walczak Agnieszka Łupicka‐Słowik Dr. Magdalena Wysocka Prof. Timo Burster Dr. Kamila Bobrek Dr. Keri Csencsits‐Smith Prof. Adam Lesner Dr. Marcin Sieńczyk 《Chembiochem : a European journal of chemical biology》2014,15(17):2605-2612
Neutrophils are a type of granulocyte important in the “first line of defense” of the innate immune system. Upon activation, they facilitate the destruction of invading microorganisms by the production of superoxide radicals, as well as the release of the enzymatic contents of their lysozymes. These enzymes include specific serine proteases: cathepsin G, neutrophil elastase, proteinase 3, as well as the recently discovered neutrophil serine protease 4 (NSP4). Under normal conditions, the proteolytic activity of neutrophil proteases is tightly regulated by endogenous serpins; however, this mechanism can be subverted during tissue stress, thereby resulting in the uncontrolled activity of serine proteases, which induce chronic inflammation and subsequent pathology. Herein, we describe the development of low‐molecular‐weight activity‐based probes that specifically target the active sites of neutrophil proteases. 相似文献
60.
Tellurite glasses with the composition of xTm_2O_3-(6-x)Y_2O_3-3Na_2O-25ZnO-66TeO_2(where 0≤x≤6)were obtained by the melt-quenching technique.Absorption(300 K),excitation(300 K) and fluorescence spectra(300 K) as well as fluorescence decay curves of Tm~(3+)-doped title glasses are presented and discussed in details.The Judd-Ofelt analysis based on the room temperature absorption spectrum was applied for determination of fundamental fluorescence properties such as radiative transition probabilities(A_T),branching ratios(β_R),radiative lifetimes(τ_R) of the emitting levels of the Tm~(3+) ion and stimulated emission cross-sections(σ_(em)).Fluorescence spectra were recorded and analysed in the visible and near-infrared spectral range.The emission and effective cross-section were calculated for the ~3F_4→~3H_6 transition,showing that the investigated glasses are promising laser host materials,operating at 1.8 μm.The observed concentration quenching and non-exponential decay curves from the ~1 G_4 and ~3H_4 states indicate nonradiative energy transfer between Tm~(3+) ions.The analysis of non-exponential fluorescence decay curves from the ~1 G_4 and ~3H_4 levels was carried out in framework of the InokutiHirayama and Yokota-Tanimoto models and energy transfer microparameters were determined.The self-quenching model was proposed for describing relaxation of the first excited state of the Tm~(3+) ion. 相似文献