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181.
Joanna Iwaniec Tadeusz Uhl Wies?aw J. Staszewski Andrzej Klepka 《Nonlinear dynamics》2012,70(1):125-140
The paper investigates changes in determinism of undamaged and cracked aluminium plates with respect to excitation frequencies. Harmonic excitation of frequencies corresponding to structural resonances has been used to vibrate the plates. Vibration responses have been analysed using recurrence plots and recurrence quantification analysis. The smallest sufficient embedding dimension has been estimated using the false nearest neighbour??s algorithm. Mutual information analysis has been applied to determine the relevant time delays. The results demonstrate that performed analysis indicates changes in dynamic behaviour of the plates with respect to various excitation frequencies and crack modes. 相似文献
182.
Alim Mohammad A. Bak Tadeusz Atanacio Armand J. Ionescu Mihail Kennedy Brendan Price William S. Du Plessis Johan Pourmahdavi Maryam Zhou Meifang Torres Allan Nowotny Janusz 《Ionics》2017,23(12):3517-3531
Ionics - This work reports the effect of tantalum (0.1–1 at.% Ta) on the photocatalytic performance of TiO2 annealed at 1373 and 1673 K in air. It was shown that addition of... 相似文献
183.
Buszewski B Ligor T Jezierski T Wenda-Piesik A Walczak M Rudnicka J 《Analytical and bioanalytical chemistry》2012,404(1):141-146
In this work, a chromatographic method for identification of volatile organic compounds was compared with canine recognition. Gas chromatography and mass spectrometry (GC-TOF MS) were used for determination of concentrations of trace gases present in human breath. The technique enables rapid determination of compounds in human breath, at the parts per billion level. Linear correlations were from 0.83-234.05 ppb, the limit of detection was the range 0.31-0.75 ppb, and precision, expressed as relative standard deviation (RSD), was less than 10.00 %. Moreover, trained dogs are able to discriminate breath samples of patients with diagnosed cancer. We found a positive correlation between dog indications and the ethyl acetate and 2-pentanone content of breath (r = 0.85 and r = 0.97, respectively). The methods presented for detection of lung cancer markers in exhaled air could be used as a potential non-invasive tool for screening. In addition, the canine method is relatively simple and inexpensive in comparison with chromatography. 相似文献
184.
Dr. Marta E. Plonska‐Brzezinska Dr. Mikołaj Lewandowski Dr. Małgorzata Błaszyk Dr. Agustin Molina‐Ontoria Prof. Dr. Tadeusz Luciński Prof. Dr. Luis Echegoyen 《Chemphyschem》2012,13(18):4134-4141
Composites of unmodified or oxidized carbon nano‐onions (CNOs/ox‐CNOs) with poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) are prepared with different compositions. By varying the ratio of PEDOT:PSS relative to CNOs, CNO/PEDOT:PSS composites with various PEDOT:PSS loadings are obtained and the corresponding film properties are studied as a function of the polymer. X‐ray photoelectron spectroscopy characterization is performed for pristine and ox‐CNO samples. The composites are characterized by scanning and transmission electron microscopy and differential scanning calorimetry studies. The electrochemical properties of the nanocomposites are determined and compared. Doping the composites with carbon nanostructures significantly increases their mechanical and electrochemical stabilities. A comparison of the results shows that CNOs dispersed in the polymer matrices increase the capacitance of the CNO/PEDOT:PSS and ox‐CNO/PEDOT:PSS composites. 相似文献
185.
Tadeusz Jankowski 《Nonlinear Analysis: Theory, Methods & Applications》2012,75(2):913-923
We use a fixed point theorem due to Avery and Peterson to establish the existence of at least three non-negative solutions of some nonlocal boundary value problems to third order differential equations with advanced arguments. An example is given to illustrate the main results. 相似文献
186.
Barbara Szafranowska Katarzyna
lepokura Tadeusz Lis 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(12):i71-i82
The synthesis and crystal structures of a series of six crystalline potassium salts of hypodiphosphoric acid, H4P2O6, are reported, namely potassium hydrogen phosphonophosphonate, K+·H3P2O6−, (I), dipotassium dihydrogen hypodiphosphate monohydrate, 2K+·H2P2O62−·H2O, (II), dipotassium dihydrogen hypodiphosphate dihydrate, 2K+·H2P2O62−·2H2O, (III), pentapotassium hydrogen hypodiphosphate dihydrogen hypodiphosphate dihydrate, 5K+·HP2O63−·H2P2O62−·2H2O, (IV), tripotassium hydrogen hypodiphosphate tetrahydrate, 3K+·HP2O63−·4H2O, (V), and tetrapotassium hypodiphosphate tetrahydrate, 4K+·P2O64−·4H2O, (VI). All the hypodiphosphate anions, viz. H3P2O6−, H2P2O62−, HP2O63− and P2O64−, adopt a staggered conformation. The P—P bond lengths [2.1722 (7)–2.1892 (10) Å] do not depend on the basicity of the anion. The compounds are organized into different types of one‐, two‐ or three‐dimensional polymeric hydrogen‐bonded networks, or simply exist in the form of isolated or dimeric units. The coordination numbers of the K+ cations range from 6 to 9, and the cationic sublattices are polymeric one‐, two‐ or three‐dimensional networks, or isolated [KO6] or dimeric [K2O12] polyhedra. 相似文献
187.
Tadeusz Micha?owski Agustin G. Asuero Maja Ponikvar-Svet Marcin Toporek Andrzej Pietrzyk Maciej Rymanowski 《Journal of solution chemistry》2012,41(7):1224-1239
The paper compares two approaches to the simulated argentometric titration of cyanide with the use of the modified Liebig?CDenigès (L-D) method, carried out according to GATES and applied with (1) classical and (2) pH-static titrations. Both approaches are discussed thoroughly and the results obtained from calculations are presented graphically. The calculations are performed with the use of an iterative computer program, based on charge and concentration balances and expressions for equilibrium constants, providing all physicochemical knowledge of the dynamic system in question. This way, physicochemical knowledge on complex electrolytic systems can be gained during the analytical procedure, i.e., the physicochemical and analytical knowledge are interrelated. The simulations follow the analytical procedures applied in experimental titrations and so provide an example of searching for the best a priori conditions for the quantitative analysis of cyanide. The computer program for pH-static titrations (described in this paper) enables one to carry out the simulation procedures with different preliminary data (concentrations, volumes). 相似文献
188.
A systematic theoretic study on clusters containing edge-bridged octahedral metal units [Nb6Cl12] n (n?=?2, 3, or 4) and a large variety of ligands has been performed. The benchmark results on the [Nb6Cl 12 i ] n+ and [Nb6Cl 12 i Cl 6 a ] n (n?=?2, 3 or 4) cluster units demonstrated the reliability of GGA PBE functional in combination with ZORA TZP basis set for the Nb-containing coordination compounds. The geometrical, electronic, and vibrational properties of large variety of substituted Nb6Cl 12 i Y 6 a clusters have been provided. One- and two-dimensional structures with a [Nb6Cl 12 i (Bipyr) x Cl 6?x a ] (x?=?2 and 4) building blocks have been proposed as good and stable candidates for new coordination polydimensional materials. 相似文献
189.
Sopasis GJ Orfanoudaki M Zarmpas P Philippidis A Siczek M Lis T O'Brien JR Milios CJ 《Inorganic chemistry》2012,51(2):1170-1179
The synthesis and magnetic properties of 13 new homo- and heterometallic Co(II) complexes containing the artificial amino acid 2-amino-isobutyric acid, aibH, are reported: [Co(II)(4)(aib)(3)(aibH)(3)(NO(3))](NO(3))(4)·2.8CH(3)OH·0.2H(2)O (1·2.8CH(3)OH·0.2H(2)O), {Na(2)[Co(II)(2)(aib)(2)(N(3))(4)(CH(3)OH)(4)]}(n) (2), [Co(II)(6)La(III)(aib)(6)(OH)(3)(NO(3))(2)(H(2)O)(4)(CH(3)CN)(2)]·0.5[La(NO(3))(6)]·0.75(ClO(4))·1.75(NO(3))·3.2CH(3)CN·5.9H(2)O (3·3.2CH(3)CN·5.9H(2)O), [Co(II)(6)Pr(III)(aib)(6)(OH)(3)(NO(3))(3)(CH(3)CN)(6)]·[Pr(NO(3))(5)]·0.41[Pr(NO(3))(3)(ClO(4))(0.5)(H(2)O)(1.5)]·0.59[Co(NO(3))(3)(H(2)O)]·0.2(ClO(4))·0.25H(2)O (4·0.25H(2)O), [Co(II)(6)Nd(III)(aib)(6)(OH)(3)(NO(3))(2.8)(CH(3)OH)(4.7)(H(2)O)(1.5)]·2.7(ClO(4))·0.5(NO(3))·2.26CH(3)OH·0.24H(2)O (5·2.26CH(3)OH·0.24H(2)O), [Co(II)(6)Sm(III)(aib)(6)(OH)(3)(NO(3))(3)(CH(3)CN)(6)]·[Sm(NO(3))(5)]·0.44[Sm(NO(3))(3)(ClO(4))(0.5)(H(2)O)(1.5)]·0.56[Co(NO(3))(3)(H(2)O)]·0.22(ClO(4))·0.3H(2)O (6·0.3H(2)O), [Co(II)(6)Eu(III)(aib)(6)(OH)(3)(NO(3))(3)(CH(3)OH)(4.87)(H(2)O)(1.13)](ClO(4))(2.5)(NO(3))(0.5)·2.43CH(3)OH·0.92H(2)O (7·2.43CH(3)OH·0.92H(2)O), [Co(II)(6)Gd(III)(aib)(6)(OH)(3)(NO(3))(2.9)(CH(3)OH)(4.9)(H(2)O)(1.2)]·2.6(ClO(4))·0.5(NO(3))·2.58CH(3)OH·0.47H(2)O (8·2.58CH(3)OH·0.47H(2)O), [Co(II)(6)Tb(III)(aib)(6)(OH)(3)(NO(3))(3)(CH(3)CN)(6)]·[Tb(NO(3))(5)]·0.034[Tb(NO(3))(3)(ClO(4))(0.5)(H(2)O)(0.5)]·0.656[Co(NO(3))(3)(H(2)O)]·0.343(ClO(4))·0.3H(2)O (9·0.3H(2)O), [Co(II)(6)Dy(III)(aib)(6)(OH)(3)(NO(3))(2.9)(CH(3)OH)(4.92)(H(2)O)(1.18)](ClO(4))(2.6)(NO(3))(0.5)·2.5CH(3)OH·0.5H(2)O (10·2.5CH(3)OH·0.5H(2)O), [Co(II)(6)Ho(III)(aib)(6)(OH)(3)(NO(3))(3)(CH(3)CN)(6)]·0.27[Ho(NO(3))(3)(ClO(4))(0.35)(H(2)O)(0.15)]·0.656[Co(NO(3))(3)(H(2)O)]·0.171(ClO(4)) (11), [Co(II)(6)Er(III)(aib)(6)(OH)(4)(NO(3))(2)(CH(3)CN)(2.5)(H(2)O)(3.5)](ClO(4))(3)·CH(3)CN·0.75H(2)O (12·CH(3)CN·0.75H(2)O), and [Co(II)(6)Tm(III)(aib)(6)(OH)(3)(NO(3))(3)(H(2)O)(6)]·1.48(ClO(4))·1.52(NO(3))·3H(2)O (13·3H(2)O). Complex 1 describes a distorted tetrahedral metallic cluster, while complex 2 can be considered to be a 2-D coordination polymer. Complexes 3-13 can all be regarded as metallo-cryptand encapsulated lanthanides in which the central lanthanide ion is captivated within a [Co(II)(6)] trigonal prism. dc and ac magnetic susceptibility studies have been carried out in the 2-300 K range for complexes 1, 3, 5, 7, 8, 10, 12, and 13, revealing the possibility of single molecule magnetism behavior for complex 10. 相似文献
190.
Kuc R 《The Journal of the Acoustical Society of America》2012,131(1):561-568
Just prior to capture the Buzz II emissions of some mouth-emitting bats, such as Eptesicus fuscus, are observed to exhibit spectra having multiple peaks. This paper proposes an echolocation strategy that uses such spectra with energy concentrated in specific frequency bands for determining target elevation. A biomimetic sonar was implemented to produce a tri-modal spectrum by driving a speaker with a signal rich in harmonics. The emission magnitudes at these harmonic frequencies measured as a function of elevation in the zero-azimuth plane form distinct beams. A template was formed from the ratio of the first harmonic and fundamental magnitudes to determine elevation. The elevation estimator exhibited a sub-degree accuracy (SD = 0.4° over a 20° interval centered at the elevation at which these two beams intersect in the zero-azimuth plane. Spectral cues from -40° to +10° elevation allow a qualitative non-linear control of sonar orientation to drive the target to the beam-intersection point where quantitative elevation estimates are available. 相似文献