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111.
112.
Maciej RadzieńskiMarek Krawczuk Magdalena Palacz 《Mechanical Systems and Signal Processing》2011,25(6):2169-2190
The objective of this paper is to introduce a new method for structural damage detection based on experimentally obtained modal parameters. The new method is suitable for detection of fatigue damage occurring in an aluminium cantilever beam. The damage has been practically realised as saw cuts of different sizes and at different locations. The first step of analysis included an attempt of damage identification with the most often used damage indicators based on measured modal parameters. For that purpose special signal processing technique has been proposed improving the effectiveness of indicators tested. However the results obtained have not been satisfactory. That was the motivation for defining new damage indicators (frequency change based damage indicator, Hybrid Damage Detection method), utilising the change of natural frequencies and any mode shape (measured or modelled) as the measurement of frequencies is much less time consuming in comparison to total mode shape measurement. It has been shown that the proposed technique is suitable for damage localisation in beam-like structures. 相似文献
113.
Soluch W Brzozowski E Lysakowska M Sadura J 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(11):2469-2474
Mass density, dielectric, elastic, and piezoelectric constants of bulk GaN crystal were determined. Mass density was obtained from the measured ratio of mass to volume of a cuboid. The dielectric constants were determined from the measured capacitances of an interdigital transducer (IDT) deposited on a Z-cut plate and from a parallel plate capacitor fabricated from this plate. The elastic and piezoelectric constants were determined by comparing the measured and calculated SAW velocities and electromechanical coupling coefficients on the Z- and X-cut plates. The following new constants were obtained: mass density p = 5986 kg/m(3); relative dielectric constants (at constant strain S) ε(S)(11)/ε(0) = 8.6 and ε(S)(11)/ε(0) = 10.5, where ε(0) is a dielectric constant of free space; elastic constants (at constant electric field E) C(E)(11) = 349.7, C(E)(12) = 128.1, C(E)(13) = 129.4, C(E)(33) = 430.3, and C(E)(44) = 96.5 GPa; and piezoelectric constants e(33) = 0.84, e(31) = -0.47, and e(15) = -0.41 C/m(2). 相似文献
114.
BACKGROUND: In this study the interspecies differences in two‐dimensional electrophoresis patterns of skeletal muscle myosin light chain (MLC) isoforms between Bos taurus (cattle), Sus scrofa (pig), Gallus gallus (chicken), Meleagris gallopavo (turkey), Anas platyrhynchos (duck) and Anser anser (goose) were characterised on the basis of specific properties of MLCs associated with their structure and mobility in gel. RESULTS: Two‐dimensional electrophoresis separations revealed species‐specific differences in the molecular weight and pI of individual MLC isoforms (MLC1f, MLC2f and MLC3f). In the case of closely related animal species such as goose and duck or turkey and chicken, significant differences occurred in MLC1f. For MLC2f, differences between cattle and turkey and between pig and chicken were around 1 and 0.3 kDa respectively. It appeared from the comparison of amino acid sequences that even MLCs with only 2% difference in sequences have different electrophoretic mobilities. CONCLUSION: Interspecies differences in skeletal MLC isoforms appeared between cattle, pig, chicken, turkey, duck and goose. The slight changes observed in the course of the aging process confirmed that these proteins are relatively little susceptible to proteolytic enzymes during meat aging. Copyright © 2011 Society of Chemical Industry 相似文献
115.
Beata Kosowska Sylwia Mozia Antoni W. Morawski Barbara Grzmil Magdalena Janus Kazimierz Kaucki 《Solar Energy Materials & Solar Cells》2005,88(3):269-280
The investigation on incorporating nitrogen group into titanium dioxide in order to obtain powdered visible light-active photocatalysts is presented. The industrial hydrated amorphous titanium dioxide (TiO2·xH2O) obtained directly from sulphate technology installation was modified by heat treatment at temperatures of 100–800 °C for 4 h in an ammonia atmosphere. The photocatalysts were characterized by UV–VIS–DR and XRD techniques. The UV–VIS–DR spectra of the modified catalysts exhibited an additional maximum in the VIS region (, ) which may be due to the presence of nitrogen in TiO2 structure. On the basis of XRD analysis it can be supposed that the presence of nitrogen does not have any influence on the transformation temperature of anatase to rutile. The photocatalytic activity of the modified photocatalysts was determined on the basis of decomposition rate of phenol and azo-dye (Reactive Red 198) under visible light irradiation. The highest rate of phenol degradation was obtained for catalysts calcinated at 700 °C (6.55%), and the highest rate of dye decomposition was found for catalysts calcinated at 500 and 600 °C (ca. 40–45%). The nitrogen doping during calcination under ammonia atmosphere is a very promising way of preparation of photocatalysts which could have a practical application in water treatment system under broader solar light spectrum. 相似文献
116.
In-vessel composting for utilizing of municipal sewage-sludge 总被引:1,自引:0,他引:1
The amount of sludge generated from wastewater treatment plants has been increasing year-by-year as the sewerage service area expanded. The composting process is considered to be one of the best management methods to stabilize different organic wastes. The main goal of this investigation was to find the optimal ratio of the quantity of the organic waste to the quantity of the sewage sludge. The process of composting was carried out in the Horstmann bioreactor (pilot scale) for 2–3 weeks and then in a compost pile for 6–12 weeks. Seven experiments were performed, with different ratios of the quantity of organic wastes to the quantity of sewage sludge. The results enabled an estimation of the quality of compost and its usefulness and also the usefulness of the bioreactor to be deduced. 相似文献
117.
Blaszczyk-Thurin Magdalena; Murali Ramachandran; Westerink M.A.Julie; Steplewski Zenon; Co Man Sung; Kieber-Emmons Thomas 《Protein engineering, design & selection : PEDS》1996,9(5):447-459
The murine monoclonal antibody BR55-2 is directed against thetumor-associated antigen Lewis Y oligosaccharide. The LewisY core antigen is a difucosylated structure consisting of fourhexose units. Analysis of binding profiles of lactoseries isomericstructures by BR552 suggest that the binding epitopeincludes the OH-4 and OH-3 groups of the ß-D-galactoseunit, the 6-CH3 groups of the two fucose units and the N-acetylgroup of the subterminal ß-D-N-acetylglucosamine (ßDGlcNAc).To elucidate the molecular recognition properties of BR552for the Y antigen, BR552 was cloned, sequenced and itsthree-dimensional structure was examined by molecular modeling.The crystal structure of BR96, another anti-Lewis Y antibody,solved in complex with a nonoate methyl ester Lewis Y tetrasaccharide,and the lectin IV protein in complex with a Lewis b tetrasaccharidecore were used as a guide to probe the molecular basis for BR552antigen recognition and specificity. Our modeling study showsthat BR552 shares similar recognition features for thedifucosylated type 2 lactoseries Lewis Y structure observedin the BR96-sugar complex. We observe that a major source ofspecificity for the Lewis Y structure by anti-Y antibodies emanatesfrom interaction with the ß-D-N-acetylglucosamineresidue and the nature of the structures extended at the reducingsite of the fucosylated lactosoamine. 相似文献
118.
Sex differences in parasite infections: patterns and processes 总被引:1,自引:0,他引:1
Sex differences in parasite infection rates, intensities, or population patterns are common in a wide range of taxa. These differences are usually attributed to 1 of 2 causes: (1) ecological (sociological in humans); and (2) physiological, usually hormonal in origin. Examples of the first cause include differential exposure to pathogens because of sex-specific behavior or morphology. The second cause may stem from the well-documented association between testosterone and the immune system; sexually mature male vertebrates are often more susceptible to infection and carry higher parasite burdens in the field. Although many researchers favor one explanation over the other, the requisite controlled experiments to rule out confounding variables are often neglected. We suggest that sex differences in disease have evolved just as sex differences in morphology and behavior, and are the result of selection acting differently on males and females. Research has often focused on proximate mechanistic explanations for the sex difference in infection rates, but it is equally important to understand the generality of the patterns in an evolutionary context. Because males potentially gain more than females by taking risks and engaging in competition, sexual selection pressure has shaped male behavior and appearance to maximize competitive ability and attractiveness. Many of the classic male attributes such as antlers on deer are testosterone-dependent, putting males in what appears to be a cruel bind: become vulnerable to disease by developing an attractive secondary sexual ornament, or risk lowered mating success by reducing it. A variety of hypotheses have been put forward to explain why males have not circumvented this dilemma. The mating system of the host species will influence the likelihood of sex differences in parasite infection, because males in monogamous species are subject to weaker sexual selection than males in polygynous species. Whether these evolutionary generalizations apply to invertebrates, which lack testosterone, remains to be seen. 相似文献
119.
Hector Artigas Pilar Cea Magdalena Dominguez Felix M. Royo Jose S. Urieta 《加拿大化工杂志》1995,73(6):862-867
A dynamic recirculating still was employed to measure isobaric vapour-liquid equilibrium at 40.0 and 101.3 kPa for the binary systems 1-bromobutane and each of the isomers of butanol. All mixtures show azeotropes at both pressures. The experimental VLE data are thermodynamically consistent and were correlated using Margules, Van Laar, Wilson, NRTL and UNIQUAC equations. 相似文献
120.