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Nanofiber materials offer a wide range of use in various production fields, e.g., different types of filtration, or areas requiring high hydrostatic resistance. They are made from different polymers, some of which are more hydrophobic than others, for instance some types of polyurethanes and polyvinylidene fluoride. However, even these polyurethanes cannot guarantee a high hydrophobicity of the final nanofiber material. To increase this desired property, we have to use the so-called hydrophobic substances like fluorocarbon. The nanofiber layer has to be prepared so that its pores do not get blocked, which would worsen its filtration capability and air permeability. This is why a roll-to-roll low-vacuum plasma was used in our case for creating a fabric with nanofiber layer for the clothing industry. The result is a nanofiber material with a hydrostatic resistance higher than a 15,000 mm water column. Under suitable conditions, we can produce a nanofiber membrane for clothing with thermophysiological properties similar to those of membranes produced with different principles, e.g., nanoporous membranes. The nanofiber membrane provides us desirable properties such as stability during repeated washing.

Our study targets some of the long-standing questions concerning the somewhat mysterious properties of chalcopyrite CuFeS2. We show that defect chemistry in connection with charge transfer within the structure is responsible for the unusual electronic and magnetic properties of CuFeS2. Specifically, our model addresses weak ferromagnetism and the high mobility of carriers on the background of a rigid antiferromagnetic structure. We show that defect structure can, counterintuitively, boost the mobility of free carriers due to defect-modified charge transfer. Further, the defect-modified charge transfer induces the weak ferromagnetism both in the Cu- and Fe-sublattice. This new view opens up space for further investigations and applications of charge transfer compounds.

The spontaneous isotopic exchange of oxygen atoms between dry powdered Ti16O2-containing minerals and gaseous C18O2was studied using gas-phase high-resolution Fourier transform infrared absorption spectroscopy (FTIR) of carbon dioxide isotopologues. The absorption rovibrational spectra of all measured carbon dioxide isotopologues were assigned and then used for quantification of the time-dependent isotope exchange of oxygen atoms (16O) from the surface crystalline lattice of the solid mineral samples with (18O) oxygen atoms from gaseous C18O2. Similar to our previous studies devoted to the isotopic exchange activity of titanium dioxide, we determined that rutile, montmorillonite, siderite, calcite, and basaltic minerals also exhibit unexpectedly significant oxygen mobilities between solid and gas phases. The rate of formation of gaseous C16O2is found to be highly dependent on the nature of the mineral sample. Our previous studies together with the results presented here suggest that such crystal–surface oxygen isotope mobilities can be explained by two mechanisms: the cluster-like structure of finely powdered materials or the existence of oxygen-deficiency sites in the structure of the surface crystal lattice.

The high‐energy‐density synthesis of NxOyspecies is simulated in gas mixtures representing an O2‐free early‐Earth atmosphere by terawatt‐kilojoule‐class laser‐induced dielectric breakdown (LIDB). These experiments differ from previous LIDB experiments due to the 100 times greater energy delivered per pulse and sensitive analysis of products by high‐resolution infrared spectroscopy. The measured yields of NO, N2O, and NO2are 0.08–8 × 1015, 5 × 1012, and 0.03–7 × 1014molec J −1. The high N2O yield is above the upper‐limit constraint of previous tabletop LIDB experiments and the expected yield of a thermochemical freeze‐out at any temperature between 2000 and 5000 K, while the NO and NO2yields are in broad agreement with freeze‐out models. Using a one dimensional chemical model of the Hadean atmosphere and a simple model of late bombardment, we compute the source flux of N2O assuming the same high production yield as measured experimentally and find the steady‐state partial pressure of N2O is insufficient to warm the climate. The climate of the Earth 4.5 to 4 billion years ago is not well known but geological evidence suggests the presence of liquid water, which is at odds with the possibility of a very‐cold early Earth. Extra greenhouse warming by atmospheric gases is thought necessary to keep the surface temperature high enough for liquid water. Nitrous oxide is a possible greenhouse gas and its high‐temperature formation in an atmosphere undergoing intense meteor bombardment may provide additional means of warming the early Earth. In this paper, we mimic the impact formation of nitrogen oxide molecules in the laboratory using a high‐energy laser‐induced plasma. The laser generates pulses 100 times more energetic than in previous studies and the new molecules are measured by infrared spectroscopy. We then compute the stable amount of nitrous oxide that might have existed 4.5 billion years ago and find this is still too small to contribute to greenhouse warming. The effect of large amounts of impact‐formed nitrogen oxides may still lead to significant short‐term consequences of a large impact, or become chemical inputs to the first stages of biochemistry, or be relevant for observational models exoplanet atmospheres in young star systems encountering heavy bombardment. A terawatt‐class laser simulation of NxOyformation by impacts finds a large yield of N2OOne‐dimensional atmospheric model shows that impact‐production of N2O is still insufficient to significantly warm the Hadean Earth A terawatt‐class laser simulation of NxOyformation by impacts finds a large yield of N2O One‐dimensional atmospheric model shows that impact‐production of N2O is still insufficient to significantly warm the Hadean Earth

This thesis deals with the assessment of the effect of the process of lamination microporous nanofiber membrane on the overall evaporative resistance of the two-layer laminate. For most multi-layer materials, lamination process is due to the deterioration of some properties of the whole laminate, particularly to the increase of the evaporative resistance. The authors of this thesis investigate the effect of the lamination primarily on the evaporative resistance of two-layer laminates. The study deals with the relations of volume porosity with the values of the evaporative resistance of the laminate too. In this thesis are both measured the separated layers of selected materials (upper material and the membrane), then the surface materials with the coated lamination points and subsequently created two-layer laminates.

Suitability of nanofiber layers for various applications is given by their morphological structure and physical properties. Structure of polymer nanofibre layers is characterized by very small diameter of the fibers and by large specific surface. For these features can polymer nanofibre membranes be widely used for special purposes- sport ,army and outdoor clothing. Thanks to the diameter and large specific surface the polymer nanofibre layers were used as a supporting structure for polyurethane hydrophilic coating. The main goal was to create 100 per cent wind resistant and water resistant coating with increased ability of steam permeability.

A review of the New Zealand Scolytinae and Platypodinae has been carried out, revealing a relatively small fauna of at least 19 indigenous Scolytinae, of which 9 species are currently undescribed, and four Platypodinae. Despite the frequent interception of exotic species in imported timber and wooden items, there are only 11 introduced Scolytinae, primarily of Australian and European origin.We provide numerous corrections of incorrect synonyms and records of occurrence in New Zealand, and a new combination, Hypocryphalus longipennis(Browne), transferred from Cryphalus, is proposed. For each species we provide its known distribution and host plants in New Zealand. None of the indigenous species are economically important in New Zealand. Of the introduced species, only Hylurgus ligniperda(Fabricius) and Hylastes ater(Paykull), which breed primarily in woody debris available in pine plantations, are abundant, but their economic impact is limited. As a vector of Dutch elm disease, Scolytus multistriatus(Marsham) could potentially have a large economic impact, although the results of a disease eradication campaign are promising. Ninety Scolytinae species and eight Platypodinae have been intercepted in shipments to New Zealand from 1952-2000, with imports of timber and other wood products being the primary pathway. Many interceptions included live specimens but, despite this, the large majority of species have not become established.

Objective: The purpose of this study was an objective consideration of possible benefits of phototherapy implemented with therapeutic laser or possibly polarized light in treating episiotomy, which is the most frequent obstetric intervention. Materials and Methods: In the present study, the authors treated a total of 2,436 women. The light sources were as follows: a laser of a wave length 670 nm, power 20 mW, with continuous alternations of frequencies 10 Hz, 25 Hz, and 50 Hz, a polarized light source of a 400-2,000 nm wavelength in an interval of power 20 mW and frequency 100 Hz and a monochromatic light source of a 660 nm wavelength and power 40 mW, with simultaneous application of a magnetic field at an induction 8 mT. Results: The work demonstrated high healing effects with minimum secondary complications in the treatment of episiotomies using a therapeutic laser at an energy density of 2 J/cm2. The application of polarized light at an energy density of 5 J/cm2 also exerted favorable therapeutic effects.

In this paper we present a detailed study of a violent evolution of the 18 September 1995 eruptive prominence observed by the Hα telescope and the Multichannel Optical Flare Spectrograph in Ondřejov. The fast changes of the prominence structure started immediately after a weak radio burst at 3 GHz. This circumstance shows the presence of non-thermal processes. In the later phase of the prominence evolution a comparison of the Hα filtergrams with the Yohkoh Soft X-ray Telescope pictures was made. For a search of fine structures in the Hα images, an image processing technique was used. A detailed analysis of observations indicates magnetic field line reconnection, mainly in space below the rising Hα prominence. These reconnection processes are manifested not only by structural changes of the Hα prominence and X-ray loops but also by the character of Doppler velocities. Evidence of splitting and rotation was found in the Hα spectrum formed close to the reconnection space, and the typical velocities of such plasma movement were evaluated. We estimated amplitudes of rotational velocities, giving evidence about the rearrangement of helical structures during the process of the eruptive prominence activation. In the conclusion we discuss some implications of our results.

The influence of a multistep intermediate pressing and sintering process on microstructure and the relation between microstructure and values of critical current density, Jc, in Bi, Pb-Sr-Ca-Cu-O high-Tc polycrystalline superconductors was studied. The Jc values increased with increasing number of pressing and sintering steps, n, only up to a certain value of n. The increase of Jc was reached by improvement of connections between grains due to compacting and by the alignment of superconducting grains in the c-axis direction. The maximal value of Jc was found for n = 5. The crack development is responsible for decreasing Jc for a higher number of steps.

The processing of Ag/Bi(Pb)-2223 tapes via the prevailing solid state reaction was investigated. A precursor powder of the composition Bi1.86Pb0.26Sr1.96Ca1.95Cu2.97O10+δcontaining mainly Bi-2223 phase was employed. Particular attention was devoted to the microstructural properties of the tapes subjected to rolling and subsequent heat treatment in one, two, and three steps, respectively. A sharp texturing gradient exists in the superconducting cores, and the repeated treatment leads to deterioration of the superconducting properties. The latter effect is ascribed to the formation of periodic defects arising during the repeated rolling of the sintered superconducting core.

Currently many different types of protective garments are used designed to protect the wearer against biological contamination (e.g., bacteria) and mechanical impurities (such as dust, drops of technical fluids, etc.). Their disadvantage is that, thanks to the materials used in the requirement of a high level of protection for the user, a very low permeability even to zero, so that for example, do not allow to remove moisture and heat from the user's body and thus their use is quite uncomfortable, and conversely, in case of the requirement of good breathability and high comfort of application have very little effectiveness in detecting biological and mechanical impurities, which is not sufficient for a number of disciplines.

A spectrophotometric method is described for the determination of iron in high purity GaAs and As or Ga, having a limit of detection of 3.5×10-5% and 7×10-5% Fe, resp. After sample dissolution and pre-reduction of Fe3+ to the bivalent state with hydroxylammonium chloride the red iron(II)-bathophenanthroline complex is formed in the presence of sodium citrate, ascorbic acid and perchlorate. It is extracted into chloroform and optical density of the resulting extract is measured at 533 nm. The effect of copper is discussed. The procedure is stated to be rapid and applicable not only to Ga, As and GaAs, but also to other materials.

We used the measurement of the thickness of alveolar septa in the lungs in (C57BI/6xDBA/2)F1mice irradiated locally in the area of the thorax with absorbed doses of 14, 16 and 18 Gy of gamma rays. The thickness of alveolar septa of the pulmonary tissue was measured using a computer image analysis.

The temperature dependence of the X-ray absorption near-edge structure (XANES) spectra at the Pr $L_{3}$ edge was measured for the (Pr1-yYy)0.7Ca0.3CoO3samples ($y=0.075$ and 0.15), in which a peculiar metal--insulator (MI) transition and a spin-state (SS) transition took place simultaneously at a critical temperature $T_{\text{MI}}$. The valence states of praseodymium ion were determined using the analyses of XANES spectra. The results suggest that the average valence of the praseodymium ion increases below room temperature from the common value 3.0+, undergoes a steepest change at $T_{\text{MI}}$, and reaches finally 3.15+ and 3.27+ at 8 K for the $y=0.075$ and 0.15 samples, respectively. The final valences are consistent with those estimated by the entropy change using the Schottky peak due to the Pr4+Kramers doublet in the low-temperature specific heat shown in our previous paper [Phys. Rev. B 82(2010) 165107].