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Abstract

A free computer program, called DiffMap, is presented for off-line evaluation of both phase maps and orientation maps from a large number of diffraction patterns recorded with a nearly parallel nano-beam scanned line-by-line over a rectangular area in a scanning transmission electron microscope (STEM). The program runs in the Windows operating system on IBM PC compatible computers. The patterns, which are recorded independently from this program by a CCD or CMOS camera or by a pixelated camera are in Tif format, serve as input to DiffMap. Many STEMs can collect such a four-dimensional electron diffraction (4D-ED) data sets by proper selection of microscope parameters, even if this fact is not over-emphasized in the operating manuals. These phase and orientation maps can complement usual compositional maps collected in the same STEM with energy dispersive x-ray spectrometers (EDS) to give a complete description of the crystalline phases. Application is exemplified on the (fcc, hcp and bcc) phases in a sample with 4 major components (Co, Cr, Fe, Ni).

Open access

Soil science, a relatively young field of research with a history of fewer than two centuries, experienced an exponential expansion in scientific output in the last decades. While the output of all sub-disciplines is growing, research efforts in these sub-disciplines differ, reflecting the importance of the subjects. The broadening focus of soil science can be detected by the content of the increasing number and diverting thematic sessions of the World Soil Science Congresses, which are held every four years since the beginning of the 20th century. The structure of the current world congress is supposed to reflect the contemporary understanding of the internal structure of soil science, including its subdivision by major themes. Considering these soil themes/sub-disciplines, we assessed the evolution of soil science in the last three decades using scientific publications as indicators. Furthermore, we evaluated the inter-linkages of soil topics within soil research using network analysis and assessed the contribution of science to the broader fields of studies, from agriculture to engineering and environmental sciences. Results show that scientific interest towards all sub-disciplines is exploding, but environment-related topics, including subjects related to climate and contamination, show an even sharper increase. As far as the internal structure of soil science is concerned, research efforts are organised around the major topics of microbiology, soil contamination, nutrients, soil physics and water management. Our study reveals that currently the highest interest towards soil is coming from ecology and environmental sciences, followed by agriculture, engineering, geology and plant sciences, respectively.

Open access
Acta Alimentaria
Authors: N. Kellner, E. Antal, A. Szabó, and R. Matolcsi

Abstract

Guignardia bidwellii, indigenous to North America, is a significant pathogen of grapes long known in Hungary, infecting only the growing green parts of the vine (leaves, petioles, shoots, and bunches). In the absence of adequate plant protection and extreme weather conditions such as a predominantly humid, warm year, black rot of grapes can be expected. The pathogen can cause high yield losses due to grape rot and reduce wine quality if the infection is severe.

The evolution of certain biogenic amine compounds were investigated under the influence of grape black rot. The results obtained showed that they were present in low concentrations from an oenological point of view. Polyphenol composition was consistent with the literature, blackening affected mainly the concentration of catechin. Black rot fungus does not produce β-glucosidase enzyme. In terms of resveratrol content, black rot has no particular effect. However, like Botrytis cinerea, it produces glycerol and, proportionally, gluconic acid in lower concentrations.

It can be concluded that black rot of grapes does not cause health problems when introduced into wine processing.

Open access
Resolution and Discovery
Authors: Péter Németh, Kit McColl, Laurence A.J. Garvie, Furio Corà, Christoph G. Salzmann, and Paul F. McMillan

Abstract

Shock waves resulting from asteroidal and laboratory impacts convert sp2-bonded graphitic material to sp3-bonded diamond. Depending on the shock pressure and temperature conditions, complex nanostructures can form that are neither graphite nor diamond but belong to the diaphite material group, which are characterized by structurally intergrown layered sp2- and sp3-bonded carbon domains. Our ultrahigh-resolution transmission electron microscopy images combined with density functional theory calculations demonstrate that diaphites have two related but distinct structural families. Here, we describe diaphite nanostructures from natural and laboratory shocked samples, provide a framework for classifying the members of these materials, and draw attention to their excellent mechanical and electronic material properties.

Open access
Progress in Agricultural Engineering Sciences
Authors: József Mihalkó, Dóra Szepesi-Bencsik, Gabriella Zsarnóczay, and László Ferenc Friedrich

Abstract

Animal food, especially meat, has played an important role in the history of mankind. Different meats can be used in the production of meat products. In addition to lean meats, mechanically deboned meat (MDM) and mechanically separated meat (MSM) can also be used in meat products. However, the latter does not qualify as meat due to damage to the muscular structure due to the high pressure applied during the separation, therefore cannot be included in the meat content of products.

The aim of our experiment was to compare whole, minced meat, MDM and MSM from turkey (raw and in the form of meat paste). Technofunctional tests (water-holding and -binding capacity), color measurement, chemical composition (moisture, protein and fat content), electron microscopic recording, rheological properties show that the quality of MSM is inferior to other meat raw materials. These properties can also result in the production of lower quality products.

Open access

Abstract

A number of methods have been applied to measure total antioxidant capacity (TAC), including FRAP, which is based on reducing the amount of iron ions in a complex compound. Researchers often use measurement of absorbance 10 min after mixing a sample with the FRAP reaction solution to calculate TAC. The FRAP solution has been shown to alter absorbance over time by ca 0.0010–0.0020 per hour, under storage conditions. This article intends to show that some substances do not fully or sufficiently react within the common analysis period. It is evident from the results that some substances react more quickly and others very slowly. Absorbance in relation to various phenols was measured. Compared to the levels of absorbance at 10 min, mean absorbance at 48 h was higher by 5,395% for vanillin, 426% for caffeic acid, 170% for sinapinic acid, 67% for gallic acid, 19% for syringic acid, and only by 4% for Trolox. Results for vanillin and caffeic acid indicate potential auto-catalysis.

Open access

Abstract

Hungarian fruit vinegars were characterised in terms of physicochemical attributes (total polyphenol content, antioxidant characteristics/FRAP, CUPRAC, ABTS/, ascorbic acid content, pH, total soluble solids), sensory profiles, and antimicrobial properties.

Both compositional and sensory profiles showed distinct patterns depending on the type of vinegar (Tokaj wine, balsamic or apple) and the additional fruit used. Balsamic vinegars maturated on rosehip, sea buckthorn, and raspberry showed outstanding antioxidant performances. Rosehip, raspberry, and quince vinegars, as well as vinegars produced from Tokaji aszú and balsamic apple obtained high scores for fruity and sweet notes.

Antimicrobial activities were tested on Gram-negative and Gram-positive organisms, including probiotic bacteria. Generally, only weak activities were obtained, which was attributed to the natural sugar content of the samples, depending on the type of the vinegar and the fruit. Similar results, but more pronounced bacterial growth inhibitions were obtained for probiotic strains, however, some probiotic strains were resistant to at least two of the vinegars. Based on these, balsamic apple, raspberry, rosehip, quince, and sea buckthorn may qualify as potential functional components of probiotic preparations containing some of the strains tested.

Open access

A COVID–19 járvány hatása a leghátrányosabb helyzetű településeken élők mindennapjaira: ahogy a hátrányos helyzetűek és a szociális szolgáltatásokat nyújtók látják

The effects of Covid-19 on the everyday life of people living in the most disadvantaged areas: as they and professionals in the social service sector see

Scientia et Securitas
Authors: Beáta Dávid, Tünde Szabó, Éva Huszti, and István Bukovics

Összefoglaló. Jelen tanulmányunk a biztonság társadalmi aspektusait egy speciális csoport, a mélyszegénységben élő családok és az őket segítő szakemberek körében vizsgálja a COVID–19 idején. Kvalitatív módszerrel (csoportos és egyéni interjúk) a makro- (szociális támogatórendszer) és a mikrotársadalmi biztonság dimenziók összefüggését, valamint a mikroszintű biztonság dimenziók közti viszonyokat elemezzük. Ez utóbbi dimenziók leírásánál a kisgyermekes családok munkaerőpiaci és ezzel együtt anyagi helyzetére, mentális egészségi állapotukra, valamint az oktatási helyzet bemutatására koncentrálunk. Az egyes témák leírásánál az érintett családok és az őket segítő szakemberek helyzetértékelése is megjelenik a velük készített interjúk elemzése alapján.

Summary. This study examines the social aspects of security among a specific group of families living in extreme poverty and the professionals helping them during Covid-19. Using a qualitative method (group and individual interviews), we analyse the relationship between macro (social support system) and micro social dimensions of security, as well as the linkages between micro-level dimensions of security. In describing the latter dimensions, we will focus on the labour market situation of families with young children, and hence on their financial situation, their mental health situation and their educational situation. The description of each theme also includes an assessment of the situation of the families concerned and the professionals who help them, based on an analysis of the interviews conducted with them. In the first phase of the study, social problems were identified on the basis of interviews with experts. In the second phase, individual interviews were conducted with the people concerned, the disadvantaged. 11 interviews were conducted with experts: 5 individual and 6 group interviews. In the second phase, 50 disadvantaged people were interviewed individually.

In general, it can be concluded that the daily life of people living in disadvantaged areas has been further affected by the pandemic. The labour market situation has changed and, in this context, the financial situation of the interviewees has further deteriorated. Single-parent families were particularly affected by these problems. The transition to online education has created difficulties for families, children, and teachers and additional tasks for social workers. In many places, the lack of accessible services, the low availability of equipment and low level of digital literacy have prevented distance learning from taking place, and the negative consequences for the population under study can only be predicted. The epidemic has affected the population not only financially but also mentally. The reduction in social life has led to an increase in domestic violence. In some areas, the number of births in disadvantaged families has increased, especially among minors. In fact, the epidemic has brought to the surface the problems that disadvantaged people face on a daily basis: unemployment and deprivation, compounded by educational underachievement. The workload of those working in the social field has also become more visible: a shortage of staff and a lack of resources. At the same time, the enormous potential and flexibility of the current human resources have been revealed.

Open access

A globális, az európai uniós vírusválság határpolitikai hatásai.

Államhatárok régi-új szerepben a Kárpát-medencében, 2020–2021

The border policy effects of the global and EU virus crises.

State borders in old and new role in the Carpathian Basin, 2020–2021
Scientia et Securitas
Author: Zoltán Hajdú

Összefoglaló. Az elmúlt mintegy másfél év alatt a COVID–19 vírus valójában több struktúrában megrengette a világot, az Európai Uniót és egyes országokat is. A világ államai rövid idő alatt bezárkóztak, az Európai Unió 30 napra lezárta külső határait, az egyes tagállamok pedig az uniós belső határokat is lezárták. Veszélybe került a schengeni rendszer. A Kárpát-medence államai az elsők között reagáltak a határok lezárásával. Az egyéni döntések kritikája erőteljesen megjelent az Európai Bizottság részéről. A globális, az európai és a szomszédállami folyamatok összefüggtek. A határok lezárása feltehetően hozzájárult a vírus terjedésének a korlátozásához. (Ausztrália példája ezt erősíti.) A határzárak a nemzetközi tranzitforgalomban, a határ menti területeken élők és az ingázók között okozták a legnagyobb bizonytalanságot, több esetben zűrzavart.

Summary. According to the first ‘official announcement’ in December of 2019 the Covid-19 virus is reported to have emerged in China. The global spread of the virus was extremely fast. On 11 March 2020, the WHO declared Covid-19 to be a global pandemic. As of 31 March 2020 about 91% of the world population lived in countries with border and travel restrictions (border-closed world). The brief analysis reviews the main processes affecting EU and Member States borders, with a special regard to Hungary and its neighbours in the Carpathian Basin. On 17 March 2020, the EU closed its external borders for 30 days.to non-EU citizens. In parallel, a number of Member States decided to close their borders to both Schengen Zone members and third countries. As a response to border closures, the EU Commission and some states organized the repatriation of about 600,000 EU citizens. On 4 March, virus was officially reported to have been detected in Hungary. On 11 March the Hungarian Government declared a national state of emergency. On 15 March the first coronavirus-related death was announced. On 16 March the Government ordered the complete closure of Hungarian borders. After a border ‘traffic chaos’ along the Austrian-Hungarian border, the Hungarian Government – with collaborations with Romania – opened humanitarian corridors for foreign citizens. The possibilities of border crossings of citizens of seven neighbours of Hungary were formed not just by Hungary. In 2020 because of different changes (modifications, opening and closing) we could form at least three categories: open borders, partly open borders, closed borders. In the neighbouring countries (Austria, Slovakia, Ukraine, Romania, Serbia, Croatia, Slovenia) the progression of the epidemic followed the same pattern. Over the past year and a half the virus crisis has actually shaken many structures of the globalized world, the European Union and many countries in the Carpathian Basin. The virus crises has disrupted intensive connections between Hungary and neighbouring countries. Neither Hungary nor its neighbours were able to insulate themselves from the epidemic waves. The border restrictions primarily affected the movements of persons. Because of ‘permanent uncertainty’ commuters were the losers of the crisis.

Open access

Iparági sérülékenység a pandémia tükrében

Industrial vulnerability in the light of the COVID-19 pandemic

Scientia et Securitas
Authors: Zsuzsanna Hauck, Tamás Vasvári, and József Vörös

Összefoglaló. Jelen tanulmányban a termelési folyamatokat, valamint statisztikai adatokat elemezve azt vizsgáljuk, hogy a pandémia során milyen hatások érték az inputokat, magát a termelést, az outputokat, illetve hogyan változtak meg olyan versenyprioritási tényezők, mint az idő, a minőség vagy a rugalmasság. Mivel a rövidebb, a kevésbé komplex és rugalmasabb értékláncok válságállóbbnak tűnnek, ez felgyorsíthatja az ellátási láncok regionalizációját, amit tovább fokoz, hogy a termelőszektor gyors visszarendeződésével szemben a szolgáltató ágazatoknak elhúzódó kilábalással kell szembenézniük. Ezért azt is megvizsgáltuk, hogy az egyes országok ellenálló képessége függ-e a termelő szektor méretétől. Eredményeink alapján, ahol nagyobb az ipar aránya, ott gyorsabban képes a gazdaság talpra állni, ami újabb lökést adhat a fejlett államok iparfejlesztési törekvéseinek.

Summary. The coronavirus epidemic posed challenges to all. However, with proper discipline, increased efficiency and adaptability, companies and economies can emerge stronger from this situation. In this study, we examine vulnerability of industries along three dimensions according to the general model of production complemented by aggregate statistics from Eurostat.

In terms of procurement, shorter value chains seem more resilient than complex and long supply chains. Supplier risks may be also mitigated by increasing the number of suppliers of critical inputs. The costs and risks of transporting goods are also increasing. 90% of industrial products are involved in international trade, mostly transported through maritime shipping that faces significant increase in tariffs, and the difficulty of replacing crews could lead to further disruptions to the operation of maritime routes. Thus, it is not surprising that the pandemic has increased the issue of supply chain flexibility and simplification, and has drawn attention to the importance of inventories and input replacement. Companies may consider to diversify production sites or even reshore or nearshore their production.

The rate of recovery varies in each sector: in services requiring a personal presence, such as tourism, the sudden economic downturn is followed by a slow growth, contrary to the rapid rebound of industrial production. Therefore, countries with significant manufacturing will witness V-shaped recovery, while higher reliance on services is characterized by slower and longer L-shaped scenario. Thus, the pandemic also pointed out that industrial production is key in a national economy: besides that industrial innovations increase productivity (and living standards) and manufacturing functions also have a significant multiplier effect on the service sector, manufacturing also has significant resistance against a pandemic. This could give a further push to the ongoing industrial development programs of developed economies such as Germany, the United States, or the European Union. At the same time, services that are able to move online show no decline, while service requiring a personal presence may struggle in the long run. Overall, structural changes are inevitable and companies have to adapt to the novel consuming and working preferences.

Open access