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101.
102.
The paper presents preliminary research whose main goal is to build a ship protection system. One of the elements of the system will be a sub-system responsible for capturing and destroying/neutralizing all dangerous objects occurring inside a guarded area. This task will be performed by a team of autonomous underwater vehicles. To construct a decision system for the vehicles, i.e. the system whose task is to provide high-level decisions regarding direction and velocity of move, many different methods can be applied. Examples are evolutionary neural networks and expert systems with fuzzy decision rules. To test usefulness of the above methods in a role of the decision system, experiments in a predator-prey problem were carried out. In the experiments, the task of vehicles-predators was to capture a vehicle-prey behaving by a simple deterministic strategy. The current paper is a report on all the experiments mentioned. 相似文献
103.
Tomasz J. Turley 《Rocks & Minerals》2013,88(3):200-201
104.
Structure, morphology and luminescence properties of nanocrystalline samples of YAl3(BO3)4 (YAB) undoped and doped with neodymium, ytterbium and chromium obtained by the sol-gel method are presented. The best results of synthesis are obtained for mannitol as polymerizing agent. Single phase of nanopowder is obtained for pure YAB. Dopants destroy the compound structure; two other compounds, namely Al18B4O33 and YBO3, were revealed by X-ray investigation. Nanopowders show isometric and needles forms, the calculated size of crystallites is about 60 nm. Their optical properties are determined and results are compared to data obtained for single crystal counterparts. It is shown that the influence of rare earth ions incorporated into YBO3 phase on luminescent spectra and excited state relaxation dynamics of the nanopowders is negligibly small when the YBO3 content is of the order of several wt%. Residual impurity phases do not affect significantly spectroscopic properties of YAB nanopowders. 相似文献
105.
Vibration analysis of machines operating under non-stationary operational conditions requires special attention. This refers to the necessity of use of order tracking algorithms together with additional advanced signal processing methods, especially when faults indicators of interest are located in resonance frequency ranges. 相似文献
106.
M.E. Lipińska S.L.H. Rebelo M.F.R. Pereira J.A.N.F. Gomes C. Freire J.L. Figueiredo 《Carbon》2012,50(9):3280-3294
Multi-walled carbon nanotubes (MWCNT) were functionalized with a variety of chemical groups by reaction of p-substituted anilines (R–Ph–NH2) in the presence and absence of isopentyl nitrite used for the in situ generation of diazonium species. All materials were characterized by X-ray photoelectron spectroscopy, thermogravimetry and infrared spectroscopy.In the presence of isopentyl nitrite, the extent of functionalization was high and nearly independent on the amount of isopentyl nitrite and on the aniline substituents (R = F, Cl, I, NH2, NO2, OH, COOH, COOEt and Et). Unexpectedly, the functionalization of MWCNT with anilines bearing electron withdrawing groups was also observed in the absence of isopentyl nitrite. In the case of OH–Ph–NH2, the reaction leads to MWCNT with the highest degree of functionalization and this can be considered as a new and efficient methodology for CNT functionalization with phenol groups. The overall reaction mechanism is discussed for both reaction conditions: confirmation of a radical chain mechanism was obtained for the reaction performed in the presence of isopentyl nitrite, while the formation of stabilized dipolar intermediate species seems to be involved in the absence of isopentyl nitrite. The materials with the highest degree of functionalization showed very good dispersions in acetonitrile even after 1 month. 相似文献
107.
Renata Cegielska-Radziejewska Grzegorz Lesnierowski Tomasz Szablewski Jacek Kijowski 《European Food Research and Technology》2010,231(6):959-964
Lysozyme (N-acetyl-muramyl-hydrolase E.C. 3.2.1.17) is a low-molecular enzyme (14,400 Da) found in body secretions, systemic
fluids and tissues of humans and animals. Antibacterial activity of lysozyme monomer is limited first of all to Gram-positive
bacteria, which is connected with the structure of the cell wall. This enzyme catalyzes hydrolysis of β-glycoside bonds (1–4),
releasing N-acetylglucosamine and N-acetylmuramic acid. The spectrum of antibacterial activity of lysozyme may be extended
thanks to modifications of the enzyme. The aim of the study was to assess antibacterial activity, hydrolytic activity and
surface hydrophobicity of different forms of lysozyme. Chemical and thermo-chemical modification of lysozyme was performed,
and the antibacterial action of lysozyme monomer and modified preparations were compared. It was found that in comparison
with monomer and the control, all modified preparations exhibit effective action against Gram (−) bacteria Pseudomonas fluorescens. A particularly effective action was found in case of lysozyme subjected to thermo-chemical modification, which was characterized
by the highest proportion of oligomeric forms and the highest hydrophobicity. 相似文献
108.
Tomasz Rzychoń Andrzej Kiełbus Jan Cwajna Jarosław Mizera 《Materials Characterization》2009,60(10):1107-1113
The AE44 (Mg–4Al–4RE) alloy was prepared by a hot-chamber die casting method. The microstructure, microstructural stability and creep properties at 175 °C were investigated. The microstructure was analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and the Rietveld method. The results show that die cast AE44 magnesium alloy consists of α-Mg, Al11RE3, Al2RE and Al2.12RE0.88 phases. The Al11RE3 phase is thermally stable at 175 °C whereas the metastable Al2.12RE0.88 phase undergoes a transition into the equilibrium Al2RE phase. The alloy investigated is characterized by good creep properties at temperatures of 175 °C and 200 °C. 相似文献
109.
Two-component films of a non-amphiphilic azo dye and a liquid crystal with strongly polar –CN group were studied at an air–water interface on the basis of the surface potential–mean molecular area dependence recorded simultaneously with the surface pressure–mean molecular area isotherm. Additionally, the morphology of the films was monitored with the aid of Brewster angle microscope. A conventional Langmuir technique was used to form dye/liquid crystal films during reduction and expansion of an area occupied by the molecules. From the surface potential value, the effective dipole moment in the first monolayer formed on the water was calculated. Moreover, the number of molecules with dipole moments directed from the water to the air with respect to those directed towards water was estimated. The influence of the two components' miscibilities upon the surface potential after addition of the dye to the liquid crystal was determined. 相似文献
110.