One of the parameters which enables the evaluation of carbonaceous material is the thermal effect of wetting. The value of the heat of wetting provides information about the surface energy and the texture of the materials immersed in the wetting liquid. Knowledge of the heat of wetting of the carbonaceous materials is used to research their sorption properties, to characterize the structure and to determine the surface area. A method of me asuring the wetting of the carbonaceous materials as one of the methods to evaluate the carbonaceous materials was proposed. On the basis of research which was conducted, one determined the heat of wetting black coal from the Brzeszcze mine by methyl alcohol and lignites from the Turów and Bełchatów mine. One of activated carbons furnished by the Gryfskand company (WD-extra) was selected for the purpose of the comparison. The enthalpy of immersion was calculated on the basis of the results, the surface of the carbonaceous materials that were studied. It was revealed that the energetic effects of wetting depend both upon the microporous structure and the chemical nature of the adsorbent. The greatest heat of wetting calculated per 1g of the carbonaceous material, which has the most developed surface area and micropore volume, was obtained for the activated carbon. However, the heat of wetting does not increase proportionally to the surface area. The study revealed that the thermal effects of wetting for fossil coal decreases with the increasing of the surface area. The linear relationship was obtained for the three samples which were studied. The highest thermal effects (ΔT) and heat of wetting (Q) among the fossil coals was determined for the lignite from the Bełchatów mine, even though this coal had the least-developed porous structure. One may discern a clear influence of the swelling process upon the measured thermal effects on the basis of this sample.
The effect of plastic deformation process on the dissolution rate of biocompatible Mg alloys was investigated. Two biocompatible MgLi1Ca0,2Zn1 and MgLi1Ca1Zn1 alloys were selected for the study. The alloys were deformed on a 100T press at a temperature of 350°C by conventional extrusion and by the equal channel angular extrusion process (ECAE). The grain size analysis showed a high degree of the grain refinement from approximately 110 mm in the initial state to 2.8 mm after the 3rd pass of the ECAE process. Compared to as-cast state, the degree of strengthening has increased after plastic forming. The results of biodegradation tests have shown a significant increase in corrosion rate after both conventional extrusion and ECAE, although after subsequent ECAE passes, this rate was observed to slightly decrease in the MgLi1Ca1Zn1 alloy. Based on the results of macro- and microstructure examinations, the corrosion progress in samples after the extrusion process was described.
Virtual reality (VR) technology now provides players with immersive and realistic experiences as never before. Spatial presence plays a crucial role in the introduction of immersive experience in a VR environment. Spatial presence is a special feeling of personal and physical presence in the displayed environment. In this study, we found that the first-person perspective (1PP) was more effective in raising the sense of spatial presence that induces immersive experience compared to the third-person perspective (3PP) in a VR shooting game. Moreover, eye blink rate was significantly higher in the 1PP compared with the 3PP. The 1PP game setting was more realistic than the 3PP setting, and may have raised participants’ sense of immersion and facilitated eye blink. These results indicate that eye blink rate is increased by the sense of spatial presence, and can be a good measure of subjective immersive experience in a VR environment. Neuroscientific evidences suggest that dopaminergic system is involved in such emotional experiences and physiological responses.
Endoscopy represents a commonly employed technique for canine enteropathies. Different trials in human intestinal endoscopy have suggested that the introduction of water for luminal distension, in place of air, improves the visualization of the mucosal texture and decreases pain.
The aim of the study was to compare water immersion (WI) vs. air insufflation (AI) during duodenoscopy in anesthetized dogs in terms of mucosal visualization and nociception.
Twenty-five dogs undergoing duodenoscopy were included. The same image of the descen- ding duodenum was recorded applying WI and AI. Each pair of images was analyzed using mor- phological skeletonization, an image entropy evaluation, and a subjective blind evaluation by three experienced endoscopists. To evaluate differences in nociception related to the procedure applied, heart rate and arterial blood pressure were measured before, during and after WI/AI. To compare the two methods, a t-test for paired data was applied for the image analysis, Fleiss’ Kappa evaluation for the subjective evaluation and a Friedman test for anesthetic parameters.
No differences were found between WI and AI using morphological skeletonization and entropy. The subjective evaluation identified the WI images as qualitatively better than the AI images, indicating substantial agreement between the operators. No differences in nociception were found.
The results of the study pointed out the absence of changes in pain response between WI and AI, likely due to the sufficient control of nociception by the anesthesia. Based on subjective evaluation, but not confirmed by the image analysis, WI provided better image quality than AI.
The compressive strength and water absorption of cement mortars with different water-binder ratio (0.35, 0.45 and 0.55) and fly ash content (0, 10%, 20% and 30%) under water immersion were investigated, and the correlation between them was further analyzed. The internal microstructure and phase composition of mortar was studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. The results show that the inside of mortar mixed with fly ash displayed the loose and porous microstructure. Therefore, the incorporation of fly ash reduced the compressive strength of mortar, especially the early strength, and the strength decreased with the increase of fly ash content, and the water absorption of mortar also increased. There was a linear correlation between the compressive strength and water absorption of mortar with the equation: fc = -3.838β + 62.332, where fc and β represented the compressive strength and water absorption, respectively. Therefore, when the water absorption of mortar immersed in water was measured, its corresponding compressive strength could be preliminarily inferred through this equation, which was of great significance for detecting and identifying the stability and safety of hydraulic structures.
Becoming more and more a multidisciplinary domain of study, the development of research in second language acquisition, and even more visibly in multilingualism, has moved away from its sole focus on cognitive aspects to social-affective dimensions. Consequently, research in these areas makes more extensive use of research methodology characteristic of social sciences. The focus on identity brings together issues of social context and the construction of one’s identity through negotiation of who we are, how we relate to the outside world and how we position ourselves in relation to others (Pavlenko 2001). Language is the main tool in this construction/ negotiation through the acquisition/learning and use of multiple languages. In relation to the development of one’s multilingual identity, the major distinction has to be made between acquiring a language in its natural context (the case of one’s mother tongue or immigration) and learning it in formal contexts. Block (2014) believes that the issue of identity can only be studied in a natural environment of language acquisition, and not in a formal instruction context. This article aims to confi rm or reject the above belief, based on evidence from various studies of bi- and multiple language users and how they perceive their identities and their relation to the languages in their possession. It includes a pilot study of trilingual language learners and their understanding of how the individual languages they know (L1, L2, L3) build their identities and the way they enrich, impoverish or challenge who they see themselves to have been by birth (Gabryś-Barker 2018). The issues discussed relate to external (other people, situations, contexts) and internal identity-building factors (individual affectivity, personality features).
The first part of this article brings the author’s reply to the participants of the panel discussion of his book Culture as Verb (Anna Łebkowska, Jakub Momro, Tomasz Rakowski and Dorota Wolska). In the second part he outlines his premises and explains the analytical vocabulary that has enabled him to move from an active to a passive ‘verbal’ understanding of culture. He also draws a broad outline of prospective new research that would complement his project. Central to it is the exploration of what he believes is the dominant contemporary cultural experience, which is based on active participation. To characterize its most important features and forms we should make use of the following, newly defi ned analytical concepts – passivity, the present moment, immersion, and testimonial authority.