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In this paper a family of lround balanced Feistel ciphers with non-bijective functions Fis being considered. For any such algorithm, the existence of impossible differentials for an arbitrary number of rounds lis proved. Construction method and lower bound of the number of such impossible differentials is obtained. The GRANULE cipher belongs to the family under consideration, for which a new approach for finding impossible differentials is proposed. Its superiority in comparison with other previously known approaches is shown both in terms of the number of impossible differentials found and in terms of the number of rounds. Experimental confirmation of the theoretical bound of the number of impossible differentials has been obtained.

Abstract: This paper presents information about new finds of the goose barnacle Lepas anatiferaLinnaeus, 1758 in the Barents Sea. Data on the capture site, depth, and date, as well as pictures and a brief description of the captured individuals, are given. Possible causes of the appearance of this species in the Barents Sea are analyzed.

For positive integers n> r> s, G(n, r, s) is the graph whose vertices are the r-element subsets of an n-element set, two subsets being adjacent if their intersection contains exactly selements. We study the chromatic numbers of this family of graphs. In particular, the exact value of the chromatic number of G(n, 3, 2) is found for infinitely many n. We also improve the best known upper bounds for chromatic numbers for many values of the parameters rand sand for all sufficiently large n.

The history of the growth of continental crust is uncertain, and several different models that involve a gradual, decelerating, or stepwise process have been proposed1–4. Even more uncertain is the timing and the secular trend of the emergence of most landmasses above the sea (subaerial landmasses), with estimates ranging from about one billion to three billion years ago5–7. The area of emerged crust influences global climate feedbacks and the supply of nutrients to the oceans8 , and therefore connects Earth’s crustal evolution to surface environmental conditions9–11. Here we use the triple-oxygen-isotope composition of shales from all continents, spanning 3.7 billion years, to provide constraints on the emergence of continents over time. Our measurements show a stepwise total decrease of 0.08 per mille in the average triple-oxygen-isotope value of shales across the Archaean–Proterozoic boundary. We suggest that our data are best explained by a shift in the nature of water–rock interactions, from near-coastal in the Archaean era to predominantly continental in the Proterozoic, accompanied by a decrease in average surface temperatures. We propose that this shift may have coincided with the onset of a modern hydrological cycle owing to the rapid emergence of continental crust with near-modern average elevation and aerial extent roughly 2.5 billion years ago. The use of triple-oxygen-isotope data from continental shales spanning the past 3.7 billion years suggests that continental crust with near-modern average elevation and extent emerged about 2.5 billion years ago.

The paper contains information about findings of four new species of gastropods previously unreported in the Barents Sea and adjacent waters. Information on the place of the find, depth, date, pictures, and a brief description of the gastropods are given. Possible causes of the appearance of this species in the Barents Sea are analyzed.

Abstract: We consider the problem of extending the integrals of motion of soliton equations to the space of all finite-gap solutions. We consider the critical points of these integrals on the moduli space of Riemann surfaces with marked points and jets of local coordinates. We show that the solutions of the corresponding variational problem have an explicit description in terms of real-normalized differentials on the spectral curve. Such conditions have previously appeared in a number of problems of mathematical physics.

Abstract: Orthogonality relations for homogeneous waves in layered plates are obtained, and they are generalized to the case of a contact with fluid layers. For layers of infinite thickness, it is shown that the homogeneous waves of the discrete spectrum are orthogonal to each other and to the waves of the continuous spectrum. For finite-size sources, exact formulas are derived for the coefficients multiplying the modes. Based on the orthogonality relations, a nonlocal radiation principle is proposed such that the infinite domain in the numerical solution of diffraction problems for layered plates can be replaced by a virtual cylinder.

Abstract: A new scheme of composite functional material based on an alloy exhibiting a shape-memory effect (SME) is proposed. The scheme provides for a giant reversible bending deformation with the use of only “one-way”-SME alloy. An experiment was performed with the use of actuator models manufactured by gluing together the rapidly quenched ribbons and electroplating the pseudoplastically predeformed ribbons of the alloy with nickel. It is shown that the theoretical estimates of the bending moment developed by the actuator and of the reversible deformations of the actuator are in good agreement with the results of the model experiments. The prospects for the use of the new scheme in micro- and nanomechanics are considered. Actuators with record small overall dimensions have been manufactured by the focused ion-beam technique.

The paper presents information about the first record of the sea star, Porania pulvillus(Poraniidae family), in the Barents Sea. The data on the location, date of the finding, depth at this location, a picture and a brief description of the captured specimen are given. Possible causes of the appearance of this species in the Barents Sea are analyzed.

The atomic structure of the characteristic defects (Mg-rich hexagonal pyramids) in p-doped bulk and MOCVD GaN:Mg thin films grown with Ga polarity was determined at atomic resolution by direct reconstruction of the scattered electron wave in a transmission electron microscope. Small cavities were present inside the defects, confirmed also with positron annihilation. The inside walls of the cavities were covered by GaN of reverse polarity compared to the matrix. Annealing of the MOCVD layers lead to slight increase of the defect size and an increase of the room temperature photoluminescence intensity. Positron annihilation confirms presence of vacancy clusters of different sizes triggered by the Mg doping in as-grown samples and decrease of their concentration upon annealing at 900 and 1000 °C. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A study of screw dislocations in hydride-vapor-phase-epitaxy (HVPE) template and molecular-beam-epitaxy (MBE) overlayers was performed using transmission electron microscopy (TEM) in plan view and in cross section. It was observed that screw dislocations in the HVPE layers were decorated by small voids arranged along the screw axis. However, no voids were observed along screw dislocations in MBE overlayers. This was true both for MBE samples grown under Ga-lean and Ga-rich conditions. Dislocation core structures have been studied in these samples in the plan-view configuration. These experiments were supported by image simulation using the most recent models. A direct reconstruction of the phase and amplitude of the scattered electron wave from a focal series of high-resolution images was applied. It was shown that the core structures of screw dislocations in the studied materials were filled. The filed dislocation cores in an MBE samples were stoichiometric. However, in HVPE materials, single atomic columns show substantial differences in intensities and might indicate the possibility of higher Ga concentration in the core than in the matrix. A much lower intensity of the atomic column at the tip of the void was observed. This might suggest presence of lighter elements, such as oxygen, responsible for their formation.

We study the spectral and polarization properties of acoustic waves propagating in nematic liquid–crystalline rubber materials. We apply the viscoelastic theory of nematic elastomers in the low–frequency (hydrodynamic) limit. Dynamic soft elasticity, exhibited by ideal nematic elastomers under certain geometries of shear at low frequencies, leads to anomalous anisotropy of energy transfer and attenuation of transverse waves. The results suggest an application of this class of materials as an acoustic polarizer medium.

Conditions for preparation of the fullerene-containing carbon black with the maximum yield of fullerenes were determined. A correlation between the dielectric constant of the carbon black in the microwave range and the yield of fullerenes was found. The relation of the fullerene-containing carbon black structure to the conditions of its preparation and dielectric constant are discussed.

Summary:  Within the scope of linear elasticity, the in-plane problem of an anisotropic plate or laminate with a circular hole and an elliptical hole reinforcement is considered. Arbitrary anisotropic elastic stiffnesses are allowed for the base plate and the reinforcement material, and for the reinforcement there is no restriction for its elliptical shape and size. The analysis of the problem is performed by the complex potential method with appropriately chosen series representations inside and outside the reinforcement region. The derived closed-form solution provides all resultant in-plane stresses and deformations within and around the hole reinforcement with little computational effort and at high accuracy. The determined solution allows a proper and effective assessment of hole reinforcements for many technical applications.

Exact solutions are obtained in the framework of the classical theory of laminates subjected to the action of normal moments, double forces, double moments or momentless double dipoles. Seven cases of such loads are considered and completed by considering the case of given transversal discontinuity of normal deflection. It is shown that, in contrast to the case of infinite straight dislocations in a pure in-plane problem, the energy of this eighth solution depends on the discontinuity orientation. Some numerical examples are presented. Besides the formal value, the obtained double-force and double-moment solutions, as well as dimensionless double dipoles, can be used to construct kernels of additional boundary integral equations (BIE). Due to the coupling phenomena in the BIE system for the region with a corner point, additional variable such as corner forces appear and require the mentioned equation.

The thermal conductivity, k, of diamond/carbon composites with different ratios of sp2/sp3-bonded carbon is measured by the laser flash technique. The thermal conductivity of nanocomposites containing 6nm diamond particles falls within the range of k=0.003–0.017W/cmK at room temperature. The thermal conductivity increases while nanopores are gradually filled with pyrolytic carbon (pyrocarbon/diamond mass ratio variation of 0.0–0.5). Transmission electron microscopy data reveal a fairly uniform mixture of two carbon phases, the diamond and matrix having similar grain sizes. Estimates show that the phonon free path is limited by dimensions of carbon matrix layer. Thermal data for coarse-grain (1–2μm) composites are also given for comparison.

Anisotropic intrinsic stress in diamond films grown by microwave plasma chemical vapor deposition has been studied by Raman spectroscopy in conjunction with transmission electron microscopy (TEM). A series of films of 200 to 1400 μm thickness were analyzed. The confocal Raman spectroscopy has given detailed information on the stress distribution within individual grains of the films with a spatial resolution of a few microns. TEM analysis showed that the main defects of the films are sets of parallel microtwin lamella, starting from grain boundaries and ending inside the grains. Near-surface micro-Raman mapping revealed the preferable adjacency of compressive and tensile stress regions located on opposite sides of grain boundaries, while the depth analysis revealed stressed zones in different points of the bulk of these films. A mechanism of the extended (micron scale) stress generation due to formation of incoherent boundaries between coalescent crystallites is suggested using a model of edge dislocation structure of intergrain boundary.

Abstract: The results of analysis of the periodic solutions obtained within the framework of complete and truncated equations for a system of identical Van-der-Pol-Duffing oscillators with nonlinear coupling are compared.

We have investigated the internal dynamic stress-strain state of elastic laminates with perfectly joined anisotropic layers in the long-wave approximation. In contrast to familiar cases, in this treatment we allow an asymmetric arrangement of plies across the thickness and the most general anisotropy. We derive the generalized governing equations for plates by an asymptotic method based on three-dimensional dynamic elasticity. We discuss the similarities and differences between the derived two-dimensional theory and earlier models of S. A. Ambarisumyan and R. M. Christensen. We show that the asymptotic accuracy of the equations depends on the type of anisotropy: (i) general anisotropy; (ii) monodinic anisotropy or orthotropy of the layers.

Severe low-temperature conditions, in which considerable part of Russian Motor Park is operated, affect vehicles negatively. Cold weather causes higher fuel consumption and C02 emissions always. It is because of temperature profile changing of automobile motors, other systems and materials. For enhancement of car operation efficiency in severe winter environment the dependency of engine warm-up and cooling time on ambient air temperature and wind speed described by multifactorial mathematical models is established. -On the basis of experimental research it was proved that the coolant temperature constitutes the engine representative temperature and may be used as representative temperature of engine at large. The model of generation of integrated index for vehicle adaptability to winter operating conditions by temperature profile of engines was developed. the method for evaluation of vehicle adaptability to winter operating conditions by temperature profile of engines allows to decrease higher fuel consumption in cold climate.

Me-incorporated Zr0.84Y0.16 oxide thin films (Me: Cu or Pd) were synthesized by magnetron co-sputtering. The film structural evolution due to metal content increase was shown: Me-doped nanocrystalline yttria stabilized zirconia (YSZ); Me-doped amorphous oxide; metal nanoparticles embedded in the amorphous oxide matrix. Annealing for 2 h at 300degC in air promoted copper oxide formation and the segregation of very fine Pd particles. XANES analysis at the Cu-K edge showed that Cu is bonded to oxygen and Zr(Y) in Cu-doped amorphous oxide; this state was not affected by the thermal treatment. XANES and resistivity analyses indicated that the Cu nanoparticles likely have oxidized surfaces while the Pd-containing films showed only minor chemical changes after annealing.