In this paper, a conventional mushroom-type EBG unit cell is made compact by etching a C-slot at its conducting surface. Further, the C-slotted mushroom-type EBG unit cell is coupled with a microstrip line using a novel groove-coupling technique to design a notch filter. The arrangement has achieved in the reduction of the electrical size of the mushroom type EBG unit cell by 46:15% and create a stop band suppression of -12 dB. The proposed EBG is applied to notch a narrow band centered at 5:2 GHz along with an ultra-wideband antenna. The far field gain of the antenna is suppressed by -5:8 dBi along the direction of its major lobe at 5:2 GHz. The overall size of the antenna system is 19x27x1:6mm3 which is compact. The performance of the antenna is validated from the simulation and measured results.
The aim of geological investigations the results of which are given in this paper was identify the presence of Carboniferous coal in the area south of Homsund (Figs. 1 and 2). The field investigations were carried out in the summer of 1979 within the scientific expedition organized by the Institute of Geophysics of the Polish Academy of Sciences (problem MR-II-16/B). The investigations covered the northwestern part of Sörkappland, south of Hornsund and west of the Wurmbrandegga and Wiederfjellet (Fig. 2).
Communities of soil invertebrates were studied in 4 types of tundra ecosystems on Spitsbergen (Hornsund area) during the vegetative season of 1989. Taxonomic composition, density and biomass of soil fauna were evaluated in the sites along a gradient of increase in the biogenic impact of bird colonies, i.e. in polygonal tundra, mossy/lichenous tundra, Calliergon stramineum moss association, and mossy associations near a colony of Little Auks (Alle die). Average total biomass of soil invertebrates increased in this site sequence from 1.1 to 25.0 g wet weight x m-2 (mainly due to collembolans and nematodes). Seasonal dynamics of all groups of soil meso- and macrofauna (Nematoda, Enchytraeidae, Aranei, Acarina, Collembola, Coleoptera, Diptera larvae) is presented and discussed.
This publication begins series of papers on taxonomy of juvenile and little known Mesozoic gastropods from Siberia and Timan region (= Pechora Basin). First part contains general part with geological framework followed by the paleontological part on taxonomy of Vetigastropoda and Caenogastropoda (exclusive of Neogastropoda). Described are 15 species of gastropods. Three of them are new. They are Chuelskia siberica (Trochidae), Ageria gankinensis (Epitoniidae), and Dzikella chuzikovensis (superfamily and family uncertain). Moreover, described is a new genus Chuelskia (Trochidae). Eight species are left in the open nomenclature. The Siberian gastropods belong mostly to the cosmopolitan fauna while the gastropods of Timan region are the same as those already described from Novaja Zemlja Islands.
The results of the detailed seismoacoustic profilling (CSP, boomar) are presented. The investigation has been carried out in February 1985 and 1988 during two Geodynamical Expeditions organized by the Institute of Geophysics of the Polish Academy of Sciences. The boomar penetration of the caldera floor went down to 150 msec. Four seismoacoustic units of volcanic formations have been determined. The unit A corresponds to pre-caldera series and occurred only in the border part of the flooded caldera. The unit contains mainly pyroclastic rocks (consolidated agglomerates and tuffs) and probably some intercalations of lavas. The units B, C and D fill up the caldera bottom and correspond to post-caldera series. The units are composed of pyroclastic rocks, containing also materials redeposited by lahars, glaciers, landwaters and by wind. The units C and D (the youngest one) were certainly deposited under water. All the units are cut by numerous faults, vents and other types of intrusions. The larger faults, en echelon type, are situated around the bottom and form a ring-fracture. Caldera was formed by succesive stages of collapsing. This process is not finished yet and volcanic activity is still alive (especially in the western part of the flooded caldera).
In this study, microstructural and crystallographic properties of phase transformations occurring with thermal effect in Fe-XMn-Mo-Si (X = 15.14wt.% ve 18.45wt.%) alloys have been investigated. The effects of (wt.%) Mn rates in the alloy on the characteristics of phase transformations were investigated by using Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and X-Ray Diffraction (XRD). SEM and TEM investigations was observed that two different martensite (ε and α') structures were formed in austenite grain. In addition, in TEM observations, the interface regions were selected over the bright field image. Crystallographic orientation relationships were obtained by the analyses of electron diffraction patterns from the interface regions. γ → α' type transformation was observed for α' particle formation, and orientation relationship was found as (1–11)γ // (011)α', [101]γ // [1–11–]α' and, γ → ε type transformation was observed for ε martensite plate formation, and the orientation relationship was found as (1–11–)γ // (0002–)ε, [1–1–0]γ // [2–110]ε. It was noticed that this orientation relationships were compatible with the literature (Kurdjumov-Sachs and Shoji-Nishiyama orientation relationship). Precipitation phase (carbide) formation was observed in microstructure analyses. The changes in the magnetic properties of the alloys having different rates of Mn as a consequence of thermal effect phase transformations was investigated by using Mössbauer Spectroscopy. The internal magnetic field, volume fractions (transformation rates), isomer shift values and magnetic characteristics of the main and product phases were revealed by Mössbauer Spectroscopy. In the Mössbauer Spectrum, it was noticed that ε-martensite and γ-austenite structures showed paramagnetic single-peak, and α'-martensite showed ferromagnetic six-peaks.
The text is dedicated to the outstanding Polish researcher of proper names — prof. Aleksandra Cieślikowa, author and co-author of many significant monographs and onomasticons, which went beyond the limits of previous onomastic studies. The most important, selected her scientific achievements and expert activities at the Polish Language Council and the Commission on Names of Localities and Physiographic Objects were presented.