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31.
K. Dziunikowska J. Figiel D. Kisielewska P. Malecki H. Rudnicka A. Zalewska S. Csorna L. Dunn A. Kocsis H.J. Lubatti K. Moriyasu K. Doroba S. Otwinowski R. Sosnowski M. Szeptycka A. Wröblewski A. Ziemiński K. Hayes P.M. Yager 《Physics letters. [Part B]》1976,61(3):316-320
Multiplicity distributions of charged secondaries, σN(π?d) are obtained. The effective multiplicities σN(π?n) and σN(π?p) are extracted using the measured spectator momentum. The probability of double scattering PN is found to be independent of multiplicity. 相似文献
32.
Istvan Kocsis Yudi Ding Nicholas H. Williams Christopher A. Hunter 《Chemical science》2021,12(37):12377
Information processing and cell signalling in biological systems relies on passing chemical signals across lipid bilayer membranes, but examples of synthetic systems that can achieve this process are rare. A synthetic transducer has been developed that triggers catalytic hydrolysis of an ester substrate inside lipid vesicles in response to addition of metal ions to the external vesicle solution. The output signal generated in the internal compartment of the vesicles is produced by binding of a metal ion cofactor to a head group on the transducer to form a catalytically competent complex. The mechanism of signal transduction is based on transport of the metal ion cofactor across the bilayer by the transducer, and the system can be reversibly switched between on and off states by adding cadmium(ii) and ethylene diamine tetracarboxylic acid input signals respectively. The transducer is also equipped with a hydrazide moiety, which allows modulation of activity through covalent conjugation with aldehydes. Conjugation with a sugar derivative abolished activity, because the resulting hydrazone is too polar to cross the bilayer, whereas conjugation with a pyridine derivative increased activity. Coupling transport with catalysis provides a straightforward mechanism for generating complex systems using simple components.Synthetic transducers transport externally added metal ion cofactors across the lipid bilayer membrane of vesicles to trigger catalysis of ester hydrolysis in the inner compartment. Signal transduction activity is modulated by hydrazone formation. 相似文献
33.
Civil engineering is a field – as are many other engineering sciences – where most of the methods used for solving optimization problems are based on experience and experiments, and models using local information, but drawn from global models. The present work outlines an interesting class of problems from this field, and initiates some possible ways to solve those problems utilizing the wide tool capabilities of interval arithmetic for error handling and interval branch-and-bound algorithms to solve the original or modified industrial models automating civil engineers' work. The investigations are in the first state but are promising both in a theoretical and in a practical sense. 相似文献
34.
O. Gryshchuk J. Karger‐Kocsis 《Journal of polymer science. Part A, Polymer chemistry》2004,42(21):5471-5481
The morphology–toughness relationship of vinyl ester/cycloaliphatic epoxy hybrid resins of interpenetrating network (IPN) structures was studied as a function of the epoxy hardening. The epoxy was crosslinked via polyaddition reactions (with aliphatic and cycloaliphatic diamines), cationic homopolymerization (via a boron trifluoride complex), and maleic anhydride. Maleic anhydride worked as a dual‐phase crosslinking agent by favoring the formation of a grafted IPN structure between the vinyl ester and epoxy. The type of epoxy hardener strongly affected the IPN morphology and toughness. The toughness was assessed by linear elastic fracture mechanics, which determined the fracture toughness and energy. The more compact the IPN structure was, the lower the fracture energy was of the interpenetrated vinyl ester/epoxy formulations. This resulted in the following toughness ranking: aliphatic diamine > cycloaliphatic diamine ≥ boron trifluoride complex > maleic anhydride. For IPN characterization, the width of the entangling bands and the surface roughness parameters were considered. Their values were deduced from atomic force microscopy scans taken on ion‐etched surfaces. More compact, less rough IPN‐structured resins possessed lower toughness parameters than less compact, rougher structured ones. The latter were less compatible according to dynamic mechanical thermal and thermogravimetric analyses. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5471–5481, 2004 相似文献
35.
I. Kocsis 《Acta Mathematica Hungarica》2008,118(4):307-312
Let X ⊂ ℝ be an interval of positive length and define the set Δ = {(x, y) ∈ X × X | x ≧ y}. We give the solution of the equation
which holds for all (x, y) ∈ Δ and (u, υ) ∈ Δ, where the functions F: X → X, G
1: Δ → X, G
2: Δ → X, and G: F(X, X) × F(X, X) → X are continuous and strictly monotonic in each variable.
This research was supported by the Hungarian Scientific Research Fund (OTKA), grant No. T-043080. 相似文献
36.
Vegso K Siffalovic P Majkova E Jergel M Benkovicova M Kocsis T Weis M Luby S Nygård K Konovalov O 《Langmuir : the ACS journal of surfaces and colloids》2012,28(28):10409-10414
We report on an in-situ observation of the colloidal silver nanoparticle self-assembly into a close-packed monolayer at the air/water interface followed by a 2D to 3D transition. Using the fast tracking GISAXS technique, we were able to observe the immediate response to the compression of the self-assembled nanoparticle layer at the air/water interface and to identify all relevant intermediate stages including those far from the equilibrium. In particular, a new nonequilibrium phase before the monolayer collapse via the 2D to 3D transition was found that is inaccessible by the competing direct space imaging techniques such as the scanning and transmission electron microscopies due to the high water vapor pressure and surface tension. 相似文献
37.
Stretching experiments on single DNA molecules indicate that, counterintuitive to expectations, DNA overwinds when stretched and, at large forces, undergoes a transition into an overstretched form indicated by a plateau on the force–displacement diagrams. It is believed that these effects are the result of non-linearities in the elastic response of DNA. We use a discrete, base pair level model to simulate the behavior of short DNA molecules, taking into account the sequence dependent physical properties of DNA alongside with the coupling between the kinematical step parameters, yet retaining the quadratic form of local elastic energy function. By constructing bifurcation diagrams of equilibrium configurations and studying the dependence on base pair combinations we show that the quadratic model is capable of explaining the overtwisting as a result of coupling between modes of deformation and overstretching as a result of shear instability. 相似文献
38.
Györgyi Horváth Krisztina Kovács Béla Kocsis Ildikó Kustos 《Chromatographia》2009,70(11-12):1645-1650
Changes in the composition of bacterial outer membrane proteins may result in antibiotic resistance and in altered invasive ability. A rapid method (microfluid chip technology) was used in this study to analyze the outer membrane protein profile changes of Erwinia strains under antibiotic effect and to compare it with the effect of essential oil and its constituents. Streptomycin, gentamicin and thyme essential oil were capable of significantly changing the protein profile. Neither of the main constituents of the essential oil (thymol and carvacrol) can be exclusively responsible for the changes induced. Quantitative changes in the protein profile may contribute to the explanation of antibacterial effect of thyme oil on pathogenic Erwinia. strains. 相似文献
39.
The fracture and failure behavior of partially consolidated discontinuous glass fiber (GF) mat reinforced thermoplastic polypropylene (Azdel SuperLite®) composite sheets of various densities (0.35, 0.5 and 0.7 g·cm−3) but with the same amount of GF (55 wt.%) were studied under static (in‐plane) and dynamic (out‐of‐plane perforation impact) conditions. The fracture toughness (KQ) determined on single edge notched static tensile loaded (SEN‐T) specimens, increased with increasing density (or surface weight as the sheet thickness was constant, viz. 2 mm). Location of the acoustic emission (AE) and mapping the temperature rise during loading of the SEN‐T specimens via infrared thermography (IT) served to estimate the damage zone and trace the crack advance. Both techniques seem to be promising tools to determine the energy release rate directly. The unexpected high KQ value was attributed to a combined effect of fiber nesting (achieved by the papermaking production technology) and high stress transfer GF length (owing to partial consolidation). This resulted in an efficient stress transfer and stress redistribution during damage zone development and growth. The resistance to perforation impact of the SuperLite® sheets also increased with their density (surface weight). 相似文献
40.
Sarra Bouchelaghem Sourav Das Romen Singh Naorem Lilla Czuni Gbor Papp Marianna Kocsis 《Molecules (Basel, Switzerland)》2022,27(2)
Propolis is a natural bee product that is widely used in folk medicine. This study aimed to evaluate the antimicrobial and antibiofilm activities of ethanolic extract of propolis (EEP) on methicillin-resistant and sensitive Staphylococcus aureus (MRSA and MSSA). Propolis samples were collected from six regions in Hungary. The minimum inhibitory concentrations (MIC) values and the interaction of EEP-antibiotics were evaluated by the broth microdilution and the chequerboard broth microdilution methods, respectively. The effect of EEP on biofilm formation and eradication was estimated by crystal violet assay. Resazurin/propidium iodide dyes were applied for simultaneous quantification of cellular metabolic activities and dead cells in mature biofilms. The EEP1 sample showed the highest phenolic and flavonoid contents. The EEP1 successfully prevented the growth of planktonic cells of S. aureus (MIC value = 50 µg/mL). Synergistic interactions were shown after the co-exposition to EEP1 and vancomycin at 108 CFU/mL. The EEP1 effectively inhibited the biofilm formation and caused significant degradation of mature biofilms (50–200 µg/mL), as a consequence of the considerable decrement of metabolic activity. The EEP acts effectively as an antimicrobial and antibiofilm agent on S. aureus. Moreover, the simultaneous application of EEP and vancomycin could enhance their effect against MRSA infection. 相似文献