109 research outputs found

    Morphology Development in Model Polyethylene via Two-Dimensional Correlation Analysis

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    Two-dimensional (2D) correlation analysis is applied to synchrotron X-ray scattering data to characterize morphological regimes during nonisothermal crystallization of a model ethylene copolymer (hydrogenated polybutadiene, HPBD). The 2D correlation patterns highlight relationships among multiple characteristics of structure evolution, particularly the extent to which separate features change simultaneously versus sequentially. By visualizing these relationships during cooling, evidence is obtained for two separate physical processes occurring in what is known as “irreversible crystallization” in random ethylene copolymers. Initial growth of primarily lamellae into unconstrained melt (“primary-irreversible crystallization”) is distinguished from subsequent secondary lamellae formation in the constrained, noncrystalline regions between the primary lamellae (“secondary-irreversible crystallization”). At successively lower temperatures (“reversible crystallization”), growth of the crystalline reflections is found to occur simultaneously with the change in shape of the amorphous halo, which is inconsistent with the formation of an additional phase. Rather, the synchronous character supports the view that growth of frustrated crystals distorts the adjacent noncrystalline material. Furthermore, heterocorrelation analysis of small-angle and wideangle X-ray scattering data from the reversible crystallization regime reveals that the size of new crystals is consistent with fringedmicellar structures (~9 nm). Thus, 2D correlation analysis provides new insights into morphology development in polymeric systems

    Indicators of Food Activity As Breeding Dairy Cattle Characteristics

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    The article presents the data of ethological studies on dairy cows of the Ayrshire breed of the second lactation under conditions of stall-tethered keeping in the spring. Animals with increased nutritional activity have milk yield per 305 days of lactation higher by 1662 kg (P> 0.999) compared with animals with reduced nutritional activity. The amount of milk fat in animals with increased food activity is 72.8 kg more (P> 0.999), and the total amount of milk protein is 47.8 kg more (P> 0.999) than in animals with reduced food activity. An increased index of food activity characterizes Ayrshire cows. Comparison of milk yields obtained from Ayrshire cows with milk yields of cows with reduced food activity leads to the establishment of the following results: there is a difference in milk yield for the first lactation of 1179 kg (P> 0.999), a difference in the amount of milk fat 53.2 kg (P> 0.99), and by the amount of milk protein – 36.4 kg (P> 0.99). Comparison of the total activity index led to the following results: the difference in milk yield per 305 days of lactation is 1386 kg (P> 0.999), in the amount of milk fat 61.3 kg (P> 0.999), milk protein 40.0 kg (P> 0.999). The highest correlation is observed between the index of food activity and milk productivity in ultra-active animals. In infra-passive cows, the correlation between the index of food activity and milk productivity is negative. Therefore, an effective means of increasing milk productivity is the selection of animals of Ayrshire breed by ethological individuality, taking into account indices of food, motor, and general activity. The studied indices of ethological activity are inherited by cows and can be effectively used in breeding and breeding with highly productive cattle of the Vologda selection

    Information technologies in teaching humanitarian disciplines

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    The use of information technology in teaching humanitarian disciplines contributes to the formation of highly qualified, competitive specialists who can adapt to rapidly changing conditions, possessing a high level of development of critical and creative thinking, ready for professional self-development and self-improvement, for the implementation of reflection, capable of setting goals and systematically achieving them. The work actualizes the importance of information technology in the training of highly qualified competitive specialists capable of implementing professional activities at a high level. The purpose of the article is to analyze the experience of implementing information technologies in teaching humanitarian disciplines. Smart boards, multimedia installations, document cameras, electronic textbooks, electronic educational platforms and others were used as information technologies used in the teaching of the humanities. The study made it possible to reveal the influence of information technologies on the level of formation of students' competencies

    Training in cooperation with the use of information technology

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    Training of modern graduate takes place in the conditions of requirements of the Federal state educational standards aimed at development of students’ competences. In order to train a competent graduate, higher education institutions are looking for ways that will make this process more effective and dynamic. The purpose of the article is to analyze the experience of higher education institutions in the implementation of training in cooperation with the use of information technology. The wide development of information technologies and their penetration into various spheres of society has determined their implementation in the educational process. The use of information technology is based on the use of personal computers. Now this tool is an integral part of the modern educational process. Placing emphasis on the fact that learning in cooperation is not a fundamentally new technology the authors say that it acquires relevance by incorporating innovative technologies. The article considers the ideas of training in cooperation with the use of information technologies, raises the importance and significance of this issue in modern educational conditions. Training in cooperation expands the students' information field. On the basis of the study of scientific literature, the features of training in cooperation, its essence and value purpose for the formation of competence of students of pedagogical University are highlighted. The study suggests an increase in students ' motivation to study materials after the introduction of information technologies that allow them to be more mobile and creative. The process of mutual learning in the process of cooperation becomes more effective. The higher the motivation of the student to study the discipline is, the higher the level of his knowledge is. The results of the study can be used in the further implementation of information technologies for the development of the learning process in cooperation

    Determination of kelp (Laminaria digitata) technological characteristics depending on the drying method

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    The paper considers four methods of drying kelp (Laminaria digitata): convective dehydration at an air temperature of minus 5 oХ, relative air humidity of 55 and 90 %; vacuum drying at a metal carrier temperature of 20°C and a vacuum depth of 250 Pa; convective dehydration at an air temperature of 20°C and a relative air humidity of 35 %. In dried algae, the final moisture content, water activity, and strength characteristics were evaluated. To determine the swelling coefficient, dry algae were pre-crushed. It was established that at a temperature of minus 5°C and a relative air humidity of 90 %, dehydration had an unsatisfactory result in terms of the final moisture content of the finished product 27.4 %. This type of drying at a relative air humidity of 55 % provides a final moisture content of the product (12.3 ¹ 0.48) % and a relatively high swelling coefficient of 6.9. Algae, dehydrated at minus 5°C, had elastic properties, in contrast to other considered methods. Vacuum drying made it possible to obtain the minimum final moisture content of dry algae and the highest swelling coefficient of 7.7. However, drying to constant weight lasted 25.5 hours. Of the considered drying options, the convective method (t = 20°C) showed the highest rate. The duration of drying to constant weight was 8 hours. The final moisture content of the product was acceptable (9.8¹1.52) %. However, the water activity after algae swelling had the highest value of 0.97¹0.004, and the swelling coefficient had a relatively low value of 6.5. In further studies, it is planned to study the effect of various methods of algae dehydration on the preservation of its biologically active substances

    Inventing a herbal tradition: The complex roots of the current popularity of Epilobium angustifolium in Eastern Europe

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    Ethnopharmacological relevance: Currently various scientific and popular sources provide a wide spectrum of ethnopharmacological information on many plants, yet the sources of that information, as well as the information itself, are often not clear, potentially resulting in the erroneous use of plants among lay people or even in official medicine. Our field studies in seven countries on the Eastern edge of Europe have revealed an unusual increase in the medicinal use of Epilobium angustifolium L., especially in Estonia, where the majority of uses were specifically related to “men's problems”. The aim of the current work is: to understand the recent and sudden increase in the interest in the use of E. angustifolium in Estonia; to evaluate the extent of documented traditional use of E. angustifolium among sources of knowledge considered traditional; to track different sources describing (or attributed as describing) the benefits of E. angustifolium; and to detect direct and indirect influences of the written sources on the currently documented local uses of E. angustifolium on the Eastern edge of Europe. Materials and methods: In this study we used a variety of methods: semi-structured interviews with 599 people in 7 countries, historical data analysis and historical ethnopharmacological source analysis. We researched historical and archival sources, and academic and popular literature published on the medicinal use of E. angustifolium in the regions of our field sites as well as internationally, paying close attention to the literature that might have directly or indirectly contributed to the popularity of E. angustifolium at different times in history. Results: Our results show that the sudden and recent popularity in the medical use of E. angustifolium in Estonia has been caused by local popular authors with academic medical backgrounds, relying simultaneously on “western” and Russian sources. While Russian sources have propagated (partially unpublished) results from the 1930s, “western” sources are scientific insights derived from the popularization of other Epilobium species by Austrian herbalist Maria Treben. The information Treben disseminated could have been originated from a previous peak in popularity of E. angustifolium in USA in the second half of the 19th century, caused in turn by misinterpretation of ancient herbals. The traditional uses of E. angustifolium were related to wounds and skin diseases, fever, pain (headache, sore throat, childbirth), and abdominal-related problems (constipation, stomach ache) and intestinal bleeding. Few more uses were based on the similarity principle. The main theme, however, is the fragmentation of use and its lack of consistency apart from wounds and skin diseases. Conclusions: Historical ethnobotanical investigations could help to avoid creating repeating waves of popularity of plants that have already been tried for certain diseases and later abandoned as not fully effective. There is, of course, a chance that E. angustifolium could also finally be proven to be clinically safe and cost-effective for treating benign prostatic hyperplasia, but this has not yet happened despite recent intensive research. Documented traditional use would suggest investigating the dermatological, intestinal anti-hemorrhagic and pain inhibiting properties of this plant, if any

    Phenological shifts of abiotic events, producers and consumers across a continent

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    Ongoing climate change can shift organism phenology in ways that vary depending on species, habitats and climate factors studied. To probe for large-scale patterns in associated phenological change, we use 70,709 observations from six decades of systematic monitoring across the former Union of Soviet Socialist Republics. Among 110 phenological events related to plants, birds, insects, amphibians and fungi, we find a mosaic of change, defying simple predictions of earlier springs, later autumns and stronger changes at higher latitudes and elevations. Site mean temperature emerged as a strong predictor of local phenology, but the magnitude and direction of change varied with trophic level and the relative timing of an event. Beyond temperature-associated variation, we uncover high variation among both sites and years, with some sites being characterized by disproportionately long seasons and others by short ones. Our findings emphasize concerns regarding ecosystem integrity and highlight the difficulty of predicting climate change outcomes. The authors use systematic monitoring across the former USSR to investigate phenological changes across taxa. The long-term mean temperature of a site emerged as a strong predictor of phenological change, with further imprints of trophic level, event timing, site, year and biotic interactions.Peer reviewe
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