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101.
Daniel Drdlik Dominik Zeman Pavel Tofel Zdenek Chlup Hynek Hadraba Katarina Drdlikova 《Ceramics International》2021,47(2):2034-2042
The development and optimisation of piezoceramics are targeted usually to enhance their piezoelectric properties evaluated by both the direct or indirect measurement methods. The presented work aims to elaborate on the correlation of one direct (Berlincourt) and two indirect (convert and field-dependent) piezoelectric measurement methods on various material states. The role of the ceramic powder treatment by ball milling and electrophoretic deposition (EPD) technique on the determined electric properties as well as basic physical and mechanical properties of (Ba0.85Ca0.15) (Zr0.1Ti0.9)O3 ceramics (BCZT) was investigated. It was found that the EPD technologically supported by milling allows obtaining thick and dense deposits (>2 mm). After sintering, the BCZT ceramics with a relative density of >95%, hardness in the range of 2.3–2.9 GPa and piezoelectric coefficients of d33* = 940 pm/V, d33(E=0) = 427 pm/V and d33 = 364 pC/N can be achieved. Reported results also suggest that indirect (field-dependent) and direct (Berlincourt) measurements of the piezoelectric coefficients can be comparable at optimal poling conditions. 相似文献
102.
103.
Korolev Vadim V. Bean Jonathan J. Nevolin Yurii M. Kucherinenko Yaroslav V. McKenna Keith P. Protsenko Pavel V. 《Metallurgical and Materials Transactions A》2022,53(2):449-459
Metallurgical and Materials Transactions A - The misorientation of 515 grain boundaries has been determined using electron backscatter diffraction data from an 18 μm thick copper foil with... 相似文献
104.
Z. G. Murzakhanov S. F. Levin I. Yu. Belov M. A. Krivilev L. M. Sharnin 《Measurement Techniques》2012,54(11):1225-1232
A new method for processing the output signal from a gravitational wave direction finder in the measurement problem of detecting
and identifying gravitational waves from binary relativistic astrophysical objects is discussed and studied. 相似文献
105.
V. V. Mamutin N. D. Ilyinskaya D. A. Bedarev R. V. Levin B. V. Pushnyi 《Semiconductors》2014,48(8):1103-1108
The special postgrowth processing of structures for quantum-cascade lasers is studied. The processing includes regrowth with a high-resistivity material (indium phosphide) with a carrier concentration of n ≈ 5 × 1010 cm?3, photolithography with various wet chemical etchants, and the fabrication of special contacts providing enhanced heat removal. The use of modified postgrowth processing provides necessary parameters satisfying requirements for high-quality devices. 相似文献
106.
Pavel Lejček 《Journal of Materials Science》2013,48(6):2574-2580
The effect of solute interaction on interfacial segregation and intergranular embrittlement is modeled on the basis of the combined Fowler and Rice–Wang approaches in a binary system using the chosen values of standard thermodynamic parameters of interfacial segregation and varied values of the binary interaction coefficients. It is clearly shown that attractive interaction strengthens interfacial segregation and substantially enhances intergranular embrittlement, while repulsive interaction exhibits an opposite effect. This finding is demonstrated in the available literature data. 相似文献
107.
Abstract The paper describes the possibility of using the speckle pattern decorrelation for determination of small deformation tensor components of an elementary object surface area in an optical image field. The relationship between the small-deformation tensor and the speckle field displacement is analysed in detail. The studied problem is presented from the approximation viewpoint of both wave and geometrical optics. 相似文献
108.
P systems (PSs) are powerful computing models based on the structure of a biological cell and on the way chemicals interact in complex biochemical reactions which take place in various compartments (or membranes) of the cell. A lot of interest has been focused on developing various forms of PSs, from cell-like to tissue-like structures. Most of the research effort has been concentrated on symbolical PSs. Numerical P systems (NPSs) have been introduced in 2006 for possible applications in economics and business processes but no other structures and applications concerning this type of PSs have been provided since then. This paper proposes a new class of NPSs, in which enzyme-like variables allow the existence of more than one production function in each membrane, while keeping the deterministic nature of the system. The way this new type of deterministic NPSs works and a possible use of it for modeling mobile robot controllers are detailed. 相似文献
109.
110.
Adéla Grégrová Eva Neradová Vojtěch Kružík Jiří Mazáč Pavel Havelec Helena Čížková 《European Food Research and Technology》2014,239(1):169-174
Possible adulteration of canned products containing spirit vinegar pickle by adding synthetic acetic acid is a significant problem of the food industry. Isotope analyses, which determine botanical origin of acetic acid and also can detect synthetic acid, were applied to detect undeclared addition of synthetic acetic acid to canned products. The aim of the study was to improve the extraction technique for the SNIF-NMR (2H/1H; site-specific natural isotopic fractionation-nuclear magnetic resonance) and IRMS (13C/12C; isotope ratio mass spectrometry) isotope methods and for an atypical matrix and to determine isotope ratios in canned vegetables pickle to prove their adulteration or authenticity. The following set of canned products was analysed: pickled cucumbers (n = 16) and one vinegar pickle purchased in the Czech market and six model (cucumber) pickles. The determined ratios of 2H/1H and 13C/12C for the pickled cucumbers proved to be authentic ranged from 89.4 to 107.0 ppm and from ?28.7 to ?15.6 ‰, respectively; for the synthetic acetic acids diluted with water they ranged from 114.2 to 129.0 ppm and from ?44.9 to ?33.4 ‰, respectively. Isotope analyses were confirmed as a reliable tool for assessing authenticity of canned products. The method enables detection of synthetic acetic acid addition into vinegars and canned vegetables containing vinegar pickle up from 20 % (of total acidity). 相似文献