Estimation of Radiated Fields of Small Horizontal Submodules Based on a Lumped-Element Model

A novel approach to the estimation of radiated electric field of small horizontal submodules is presented. The principle idea is to describe the radiating submodule-on-motherboard structure with a lumped-element equivalent circuit which includes both the geometrical and the electrical parameters. The electromagnetic emission from the structure is approximated by the radiation characteristics of a Hertzian dipole driven by the antenna voltage resulting from the connector equivalent circuit. Therefore, no time consuming numerical field simulations are needed to evaluate the radiated electric field. Instead, a fast frequency circuit analysis with e.g. PSPICE is sufficient. Moreover, this modeling approach provides a clear insight concerning the influence of geometrical and electrical parameters with respect to radiated emissions. Finally, the computational solutions are compared with experimental results, demonstrating a good correspondence regarding engineering purposes

Rizik pothranjenosti kod slavonaca starije životne dobi uporabom „mini nutritional testa“- pilot istraživanje

Od 340.000 stanovnika Osječko – baranjske županije 63.000 (19%) su ljudi starije životne dobi (> 60 godina starosti), 37.834 (12%) žena i 25.008 (8%) muškaraca.Osobe starije životne dobi   mogu biti sklone malnutriciji, poremećaju prehrane koji nastaje kao posljedica nedovoljne, neuravnotežene ili neumjerene prehrane, ili pak poremećene apsorpcije te iskorištavanja nutrijenata od strane samog organizma.  Posljedice malnutricije kod starijih ljudi očituju se kao: gubitak mišićne mase, slabost i brzo zamaranje, poremećeni imunosni odgovor, slabo zarašćivanje rana, poremećen rad organa, sklonost infekcijama, sepsa i smrt

Ascorbic Acid as Corrosion Inhibitor for Steel in Alkaline Media Containing Chloride Ions

The investigation of nature-designed molecules and blends of naturally synthesized chemical compounds as possible inhibitor candidates for reinforcing steel in concrete is of raising interest due to the health and environmental hazards involved in the use of most inorganic corrosion inhibitors. In the alkaline media of concrete pore solution, the oxide film is present on the surface of the reinforcing steel. The ingress of chloride ions and/or carbon dioxide into the concrete destabilizes the passive film leading to a higher rate of metal dissolution through the appearance of localized forms of corrosion. This study investigates pitting inhibition with ascorbic acid (AA), by analyzing the polarization curves in the presence and absence of the inhibitor. Inhibition action was evaluated from its ability to suppress the cathodic reaction of oxygen reduction as well as from its ability to suppress the onset of pitting. The mechanism of the inhibitor action was deduced by comparative interpretation of the inhibitor’s molecular properties and the data obtained from electrochemical experiments

Highly Charged Ion Production Using an Electrode in Biased and Floating Modes

One of the most popular ways to obtain higher beam intensities in ECR ion sources is to install an electrode (usually disc) into the plasma chamber. Examined this method in detail we found that majority of the groups observed the beam intensity improvement by supplying a suitable biased voltage to the electrode and an electron current was injected into the plasma. A few groups observed the enhancement, however, when the electrode operated at floating potential - without being an electron donor. Only a few (and sometimes contradictionary) information was found on the optimised properties of the electrodes, i.e. position, dimension, shape, material. In spite of the great success of the "biased-disc" method, the mechanism is still not completely clear. In this contribution, as one step of understanding, we examine what condition we observed the above mentioned two modes. The experiments were performed at the 18 GHz RIKEN and at the 14.5 GHz ATOMKI ECR ion sources. It was found that effect of the electrode is strongly depends on the local plasma parameters and on the position of the electrode. At certain mirror ratios and electrode positions we needed to negatively bias the electrode and inject electrons into the plasma. The electrode operated as an electron source (Electron Donor ED mode). At higher mirror ratios and other axial positions the electrode works by directly changing the plasma potential dip (Potential Tuner PT mode). These two modes were checked and successfully found both in continuos and in pulsed mode operation. In both (ED and PT) modes we generated higher highly charged ion currents in the RIKEN-ECRIS than without the electrode

Mechanisms of Fracture in Neutron-Irradiated 15Ch2MFA Steel

The influence of irradiation on fracture properties of 15Ch2MFA pressure vessel steel is studied. The distribution of inclusions and carbides is characterized. The quantitative fractography of broken Charpy specimens is carried out. The correlation of crack initiation energy and the area of ductile fracture adjacent to the notch is identified. It is shown that most of the absorbed energy belongs to the stage preceding the cleavage crack initiation. From the fracture surface of Charpy specimens the distribution of ductile dimples is investigated. The relationship between the distributions of ductile dimples and second phase particles is discussed.Изучено влияние облучения на разрушение корпусной стали 15Х2МФА. Показано рас­пределение включений и карбидов. Выпол­нен анализ образцов, разрушенных по мето­ду Шарпи, с помощью количественной фрактографии. Выявлена корреляция между энергией зарождения трещины и зоной вяз­кого разрушения вблизи надреза. Установ­лено, что большая часть энергии поглоща­ется на стадии, предшествующей возникно­вению трещины скола. Исследовано распре­деление ямок вязкого разрушения на поверхности образцов Шарпи. Оценена зави­симость между распределением ямок и частицами вторичных фаз

RILEM TC 277-LHS REPORT: A review on the mechanisms of setting and hardening of lime-based binding systems

The main objective of RILEM TC LHS-277 “Specifications for testing and evaluation of lime-based repair materials for historic Structures” is the revision, adaption and, when necessary proposal, of the test methods to accurately study lime-based binding systems and mixtures, such as mortars and grouts. The empiric use of the lime-based composites and the predominant employ of cement in the field of Civil Engineering have led to the widespread application of test methods developed for cement-based composites to test the former. However, the clear differences in composition and performance between modern cement binders and lime-based materials would advise to explore specific test methods for the latter. To undertake this task the previous knowledge on the mechanisms of setting and hardening of these binders must be revised, arranged and synthesized. Processes such as drying, carbonation, hydration and pozzolanic reaction may occur during the setting and hardening of lime-based mortars and competition between them cannot be underestimated. With the aim of underpinning the revision and proposal of test methods for lime-based systems, this review paper reports a comprehensive study of the mechanisms of setting and hardening of these binders, considering the variability of the composition, which includes pure air lime as well as lime with hydraulic properties, lime-cement and lime-pozzolan systems.authorsversionpublishe

Dynamics of a geomagnetic storm on 7–10 September 2015 as observed by TWINS and simulated by CIMI

For the first time, direct comparisons of the equatorial ion partial pressure and pitch angle anisotropy observed by TWINS and simulated by CIMI are presented. The TWINS ENA images are from a 4-day period, 7–10 September 2015. The simulations use both the empirical Weimer 2K and the self-consistent RCM electric potentials. There are two moderate storms in succession during this period. In most cases, we find that the general features of the ring current in the inner magnetosphere obtained from the observations and the simulations are similar. Nevertheless, we do also see consistent contrasts between the simulations and observations. The simulated partial pressure peaks are often inside the observed peaks and more toward dusk than the measured values. There are also cases in which the measured equatorial ion partial pressure shows multiple peaks that are not seen in the simulations. This occurs during a period of intense AE index. The CIMI simulations consistently show regions of parallel anisotropy spanning the night side between approximately 6 and 8&thinsp;RE, whereas the parallel anisotropy is seen in the observations only during the main phase of the first storm. The evidence from the unique global view provided by the TWINS observations strongly suggests that there are features in the ring current partial pressure distributions that can be best explained by enhanced electric shielding and/or spatially localized, short-duration injections.</p