Danaus chrysippus (Linnaeus, 1758) (Lepidoptera, Nymphalidae, Danainae), nova vrsta u hrvatskoj fauni

On August 15, 2004, three specimens of Danaus chrysippus (Linnaeus, 1758) were caught at the mouth of the Neretva River near the town of Ploče in South Dalmatia. This is the first record of this migratory species in Croatia. A review of its zoogeographical characteristics and distribution in Europe is given. The results have been discussed and further study of this species is recommended.Tri primjerka vrste Danaus chrysippus (Linnaeus, 1758) ulovljena su 15. kolovoza 2004. godine na ušću rijeke Neretve, blizu grada Ploča u južnoj Dalmaciji. To je prvi nalaz ove migratorne vrste za Hrvatsku. Prikazane su zoogeografske značajke i rasprostranjenost spomenute vrste u Europi. Rezultati su raspravljeni i preporučeno je daljnje istraživanje ove vrste

Disorder-Induced Critical Phenomena in Hysteresis: Numerical Scaling in Three and Higher Dimensions

We present numerical simulations of avalanches and critical phenomena associated with hysteresis loops, modeled using the zero-temperature random-field Ising model. We study the transition between smooth hysteresis loops and loops with a sharp jump in the magnetization, as the disorder in our model is decreased. In a large region near the critical point, we find scaling and critical phenomena, which are well described by the results of an epsilon expansion about six dimensions. We present the results of simulations in 3, 4, and 5 dimensions, with systems with up to a billion spins (1000^3).Comment: Condensed and updated version of cond-mat/9609072,``Disorder-Induced Critical Phenomena in Hysteresis: A Numerical Scaling Analysis'

Universal Pulse Shape Scaling Function and Exponents: A Critical Test for Avalanche Models applied to Barkhausen Noise

In order to test if the universal aspects of Barkhausen noise in magnetic materials can be predicted from recent variants of the non-equilibrium zero temperature Random Field Ising Model (RFIM), we perform a quantitative study of the universal scaling function derived from the Barkhausen pulse shape in simulations and experiment. Through data collapses and scaling relations we determine the critical exponents $\tau$ and $1/\sigma\nu z$ in both simulation and experiment. Although we find agreement in the critical exponents, we find differences between theoretical and experimental pulse shape scaling functions as well as between different experiments.Comment: 19 pages (in preprint format), 5 figures, 1 tabl

Assessment of Liquefaction Potential Relevant to Choice of Type and Depth of Foundations in Seismically Active Areas

There is evidence of great increase of pore pressures in saturated sand soils during cyclic loading caused by earthquakes. These increased pore pressures can often increase to effective stresses in soil. Dependant on sand density, this can lead to a total loss of shear strength, liquefaction or greater deformability of soil. Emergence of liquefaction or great deformations within soil can cause significant damage or total destruction of constructions on the ground, even when they have been correctly designed. For this reason, it is very important to perform detailed geotechnical and seismic investigations of ground conditions and evaluate liquefaction potential for saturated sand soil in seismically active terrain. It is not possible to design stable constructions in certain types of terrain without the analyses of liquefaction potential. This paper refers to the comparative cost-analyses of two possible ways of the foundations of the business complex: shallow foundations with stabilization of potentially liquefiable sand deposit using vertical gravel drains versus deep pile foundation on unliquefiable soil

Viscoelastic Depinning of Driven Systems: Mean-Field Plastic Scallops

We have investigated the mean field dynamics of an overdamped viscoelastic medium driven through quenched disorder. The model introduced incorporates coexistence of pinned and sliding degrees of freedom and can exhibit continuous elastic depinning or first order hysteretic depinning. Numerical simulations indicate mean field instabilities that correspond to macroscopic stick-slip events and lead to premature switching. The model is relevant for the dynamics of driven vortex arrays in superconductors and other extended disordered systems.Comment: 4 pages, 2 figure

Hysteresis and Avalanches in the Random Anisotropy Ising Model

The behaviour of the Random Anisotropy Ising model at T=0 under local relaxation dynamics is studied. The model includes a dominant ferromagnetic interaction and assumes an infinite anisotropy at each site along local anisotropy axes which are randomly aligned. Two different random distributions of anisotropy axes have been studied. Both are characterized by a parameter that allows control of the degree of disorder in the system. By using numerical simulations we analyze the hysteresis loop properties and characterize the statistical distribution of avalanches occuring during the metastable evolution of the system driven by an external field. A disorder-induced critical point is found in which the hysteresis loop changes from displaying a typical ferromagnetic magnetization jump to a rather smooth loop exhibiting only tiny avalanches. The critical point is characterized by a set of critical exponents, which are consistent with the universal values proposed from the study of other simpler models.Comment: 40 pages, 21 figures, Accepted for publication in Phys. Rev.

Hysteresis, Avalanches, and Disorder Induced Critical Scaling: A Renormalization Group Approach

We study the zero temperature random field Ising model as a model for noise and avalanches in hysteretic systems. Tuning the amount of disorder in the system, we find an ordinary critical point with avalanches on all length scales. Using a mapping to the pure Ising model, we Borel sum the $6-\epsilon$ expansion to $O(\epsilon^5)$ for the correlation length exponent. We sketch a new method for directly calculating avalanche exponents, which we perform to $O(\epsilon)$. Numerical exponents in 3, 4, and 5 dimensions are in good agreement with the analytical predictions.Comment: 134 pages in REVTEX, plus 21 figures. The first two figures can be obtained from the references quoted in their respective figure captions, the remaining 19 figures are supplied separately in uuencoded forma

Surface modification of laser welded nimonic 263 sheets

Laser surface treatment is both a thermomechanical and mechanical process, based on the ability of a high energy laser pulse to generate shock waves and plastic deformation in metallic materials. Laser welding is a high energy density process with many advantages such as narrow heat affected zone, lower heat input and lower heat/energy distortion compared to conventional welding processes. In this paper, Nimonic 263 alloy sheets are laser welded by Nd:YAG laser using different laser processing parameters. The microstructure, surface roughness and mechanical properties are investigated. Welded joints are mechanically treated by laser in order to improve the surface and mechanical characteristics. Mechanical characteristics are determined by tensile test, and fractures and laser treated weld surfaces are observed by scanning and optical microscopy. Surface topography is analysed by optical profilometry and micro hardness is measured by Vickers method

Surface modification of laser welded nimonic 263 sheets

Laser surface treatment is both a thermomechanical and mechanical process, based on the ability of a high energy laser pulse to generate shock waves and plastic deformation in metallic materials. Laser welding is a high energy density process with many advantages such as narrow heat affected zone, lower heat input and lower heat/energy distortion compared to conventional welding processes. In this paper, Nimonic 263 alloy sheets are laser welded by Nd:YAG laser using different laser processing parameters. The microstructure, surface roughness and mechanical properties are investigated. Welded joints are mechanically treated by laser in order to improve the surface and mechanical characteristics. Mechanical characteristics are determined by tensile test, and fractures and laser treated weld surfaces are observed by scanning and optical microscopy. Surface topography is analysed by optical profilometry and micro hardness is measured by Vickers method

Dvojni lijekovi primakina i nesteroidnih protuupalnih lijekova: Sinteza, hvatanje slobodnih radikala, antioksidativno djelovanje i keliranje Fe2+ iona

Novel primaquine conjugates with non-steroidal anti-inflammatory drugs (PQ-NSAIDs, 4a-h) were prepared, fully chemically characterized and screened for radical scavenging and antioxidant activities. The synthetic procedure leading to twin drugs 4a-h involved two steps: i) preparation of NSAID benzotriazolides 3a-h from the corresponding NSAID (ibuprofen, ketoprofen, fenoprofen, ketoprofen hydroxy and methylene analogues, diclofenac or indomethacin) and benzotriazole carboxylic acid chloride (BtCOCl, 1), ii) reaction of intermediates 3a-h with PQ. The prepared PQ-NSAIDs exerted moderate activities in the DPPH free radical test and -carotene-linoleic acid assay. Moreover, ketoprofen derivatives 4d and 4b demonstrated a notable Fe2+ chelating ability as well. On the other hand, negligible antiproliferative and antituberculotic effects of conjugates 4a-h were observed.U radu je opisana sinteza novih konjugata primakina s nesteroidnim protuupalnim lijekovima (PQ-NSAIDs, 4a-h), njihova potpuna karakterizacija te testiranje sposobnosti hvatanja slobodnih radikala i antioksidativnog djelovanja. Sintetski postupak za pripravu dvojnih lijekova 4a-h uključuje dva koraka: i) pripravu NSAID-benzotriazolida 3a-h iz odgovarajućih nesteroidnih protuupalnih lijekova (ibuprofena, ketoprofena, fenoprofena, hidroksi i metilenskih analoga ketoprofena, diklofenaka i indometacina) i klorida 1-benzotriazol karboksilne kiseline (BtCOCl, 1), ii) reakciju intermedijera 3a-h s primakinom. Novi PQ-NSAID konjugati pokazuju umjerenu sposobnost hvatanja slobodnih radikala u DPPH testu te umjereno antioksidativno djelovanje u pokusu s -karotenom i linoleinskom kiselinom. Osim toga, derivati ketoprofena 4d i 4b imaju primjetnu sposobnost keliranja Fe2+ iona. Svi konjugati 4a-h pokazuju vrlo slabo antiproliferativno i antituberkulotsko djelovanje