Superconducting quantum interference device setup for magnetoelectric measurements

A commercial superconducting quantum interference device (SQUID) setup (MPMS 5S from Quantum Design), equipped with a magnetic ac susceptibility option, is modified for measurements of the linear magnetoelectric (ME) effect, i.e., of the magnetic moment induced by an applied external electric field in a ME sample. Test measurements on a Cr(2)O(3) (111) single crystal are in excellent agreement with previously reported data of its ME susceptibility. The main advantages of the proposed setup are the improved precision due to the high sensitivity of the SQUID magnetometer in combination with the lock-in technique and a relatively simple experimental realization.     

Specific optimal estimation of special Markov jump processes

A solution to the filtering problem of states of special Markov jump processes that is optimal in the mean-square sense at the class of polynomial observation functions is presented. A comparison of the proposed estimates with the known estimates of optimal linear and nonlinear filtering is given.     

Material surface layer damage estimation for cyclic loading conditions using the nanoindenting and nanoscratching techniques

The nanoindenting method is based on the automatic measurement and recording of the force acting on the indenter (10⁻²-5 N) and the depth of indentation (10⁻²-200 μm). The scratch hardness or nanoscratching method is based on the continuous recording of resistance forces to movement of the indenter impressed into the surface. __________ Translated from Problemy Prochnosti, No. 4, pp. 132–139, July–August, 2006.     

Resonant charge transfer in back-scattering of H-atoms from the Cs adsorbates on the Cs/Cu(1 1 1) surface

We use the wave packet propagation approach to study the dynamics of resonant charge transfer in hydrogen back-scattering from Cs adsorbates on Cu(1 1 1). The affinity level of the projectile strongly interacts with an adsorbate-localized state leading to an important modification of the projectile–substrate resonant charge transfer. At very low collision energies (<2.5 eV) the adiabatic evolution of the system leads to the blocking of the negative ion formation in back-scattering of neutral hydrogen atoms from Cs adsorbate. At higher energies non-adiabatic transitions exist, and negative ion formation is possible.     

Ion-induced electron emission – monitoring the structure transitions in graphite

The temperature dependence of ion-induced electron emission yield γ under 30 keV Ar⁺ ion impacts at incidence angles θ = 0−80° under dynamically steady-state conditions has been measured for polygranular graphite POCO-AXF-5Q. The fluencies were 10¹⁸–10¹⁹ ion/cm², the temperatures varied from the room temperature (RT) to 400 °C. The RHEED has shown that same diffraction patterns correspond to a high degree of disorder at RT. At high temperature (HT), some patterns have been found similar to those for the initial graphite surfaces. The dependence γ(T) has been found to be non-monotonic and for normal and near normal ion incidence manifests a step-like increase typical for a radiation induced phase transition. At oblique and grazing incidence (θ > 30°), a broad peak was found at T_p = 100 °C. An analysis based on the theory of kinetic ion-induced electron emission connects the behavior of γ(θ,T) to the dependence of both secondary electron path length λ and primary ion ionizing path length R_e on lattice structure that drastically changes due to damage annealing.     

Aging of Vascular System Is a Complex Process: The Cornerstone Mechanisms

Aging is one of the most intriguing processes of human ontogenesis. It is associated with the development of a wide variety of diseases affecting all organs and their systems. The victory over aging is the most desired goal of scientists; however, it is hardly achievable in the foreseeable future due to the complexity and ambiguity of the process itself. All body systems age, lose their performance, and structural disorders accumulate. The cardiovascular system is no exception. And it is cardiovascular diseases that occupy a leading position as a cause of death, especially among the elderly. The aging of the cardiovascular system is well described from a mechanical point of view. Moreover, it is known that at the cellular level, a huge number of mechanisms are involved in this process, from mitochondrial dysfunction to inflammation. It is on these mechanisms, as well as the potential for taking control of the aging of the cardiovascular system, that we focused on in this review.     

Investigation of characteristics of planar leaky-wave antenna arrays designed for broadside radiation

The results of computer simulation and experimental investigations of new planar leaky-wave antenna arrays designed for microwave and EHF bands and for the mode of radiation normal to the aperture plane have been presented. These arrays comprise single-layer shielded dielectric waveguides and metal-strip periodic diffraction gratings. The specified antennas ensure the radiation efficiency of no less than 50% and the gain of about 28–30 dB within the 3–4% frequency band.     

Results from tests of the P-67 boiler used as part of a 800-MW power unit

Results from the balance tests of a retrofitted P-67 boiler carried out in the period 2006–2008 are presented. The tests involved assessment of the change with time of the heating-surface thermal efficiency coefficients in running the power unit at its base loads in the range 740–800 MW, with seven to eight coarsegrinding mills switched into operation, with the open and closed gate values installed in the channels supplying air-powder mixture to the fourth-tier burners, and with the fraction of air supplied for lower blasting equal to 5–7% and that for the startup burners, 2%. The combined cleaning system operated in its design mode with additional blowing operations according to special control signals. The furnace waterwalls and the convective shaft surfaces were subjected to mechanical cleaning every year during current repairs.     

Intrinsic second-order nonlinearity in chalcogenide glasses containing HgI2

Frequency conversion using nonlinear optical (NLO) crystals is widely used in advanced photonic technologies to produce coherent light in the spectral regions where the available laser sources are missing. Isotropic glasses usually do not show second order nonlinear processes like second harmonic or difference frequency generation (SHG, DFG) except for temporarily induced anisotropy under external stimuli. Here, we show that a HgI₂–Ga₂S₃–GeS₂ homogeneous glass exhibits a strong intrinsic SHG response comparable with that of the well-known NLO single crystal LiNbO₃. The origin of this extremely rare phenomenon seems to be noncentrosymmetric bent HgI₂ molecules embedded in a sulfide glassy host. Taking into account the unique properties of chalcogenide glasses (wide IR transmission, low phonon density, unlimited ability to be modified changing the appropriate glass properties, fiber drawing and thin layer design), the observed phenomenon opens up the possibility of creating fundamentally new devices for mid-IR photonics.