Recent advances in bio-based polymers and composites: Preface to the BiPoCo 2012 Special Section

The increasing environmental awareness of the society has become an important factor in recent decades affecting legislation, commerce and industry as well as research and development to a great extent [1-7]. This tendency has also been recognized by the European Community, which supports numerous projects in order to promote innovative solutions leading to a sustainable economy. Three such projects of the Seventh Framework Programme with overlapping scopes, Biostruct [8], Forbioplast [9] and Woody [10], focused on the valorization of forest-derived resources for the production of various bio-based products, including polymers, additives, and composites with natural reinforcements. The leaders of these projects decided to join forces to organize a conference in order to create a possibility to disseminate their results as well as to increase the efficiency of their research and development by exchanging ideas with leading experts in the field. The International Conference on Bio-based Polymers and Composites (BiPoCo 2012) was organized for the first time in Siófok, Hungary, between May 27th and 31th, 2012, with 234 registered participants delivering more than 90 oral and 110 poster presentations. Scientific and technological lectures focused on the theory and practice of biopolymers, renewable-based monomers, fillers and additives as well as sustainable polymer blends and composites with possible application in packaging, agriculture, automotive or biomedicine. In the following sections we provide a short overview of the main research areas and presentations related to the event, and by doing so, continue the line set by Filip Du Prez, Jean-Marie Raquez and Philippe Dubois as Editors of the recent Biobased Polymers and Related Materials special issue of the European Polymer Journal [11]. Below we introduce to the reader the BiPoCo 2012 Special Section containing four feature articles and several research papers

Interactions, structure and properties in poly(lactic acid)/thermoplastic polymer blends

Blends were prepared from poly(lactic acid) (PLA) and three thermoplastics, polystyrene (PS), polycarbonate (PC) and poly(methyl methacrylate) (PMMA). Rheological and mechanical properties, structure and component interactions were determined by various methods. The results showed that the structure and properties of the blends cover a relatively wide range. All three blends have heterogeneous structure, but the size of the dispersed particles differs by an order of magnitude indicating dissimilar interactions for the corresponding pairs. Properties change accordingly, the blend containing the smallest dispersed particles has the largest tensile strength, while PLA/PS blends with the coarsest structure have the smallest. The latter blends are also very brittle. Component interactions were estimated by four different methods, the determination of the size of the dispersed particles, the calculation of the Flory-Huggins interaction parameter from solvent absorption, from solubility parameters, and by the quantitative evaluation of the composition dependence of tensile strength. All approaches led to the same result indicating strong interaction for the PLA/PMMA pair and weak for PLA and PS. A general correlation was established between interactions and the mechanical properties of the blends

Tündérkertünk gyermekversei

2004-ben a Hargita Kiadóhivatal erdélyi magyar gyermekverskötetet jelentetett meg Tündérkert címmel Ferenczes István és Fekete Vince társszerkesztésében. Ez a szerencsés helyzet alkalom arra, hogy szót ejtsünk az erdélyi magyar gyermeklíráról, észrevételeket fogalmazzunk meg egyrészt a választott kötetcímmel, másrészt magával az antológiával kapcsolatban

Nomen est omen

Ez az állítólag Plautusnak tulajdonítható latin mondás a nevekben rejtőzködő végzetre figyelmeztet bennünket. A kolozsvári Művelődés is nolens volens vállalja saját sorsát, és annak a tág diszciplínának a hazai fórumaként tevékenykedik, amelyet művelődéstörténetként tart számon a szakirodalom. A folyóirat és a köréje szerveződő egyéb fórumok (könyvkiadó, alapítvány) az erdélyi magyar művelődéstörténetet szolgálják

Investigations on the wastewater of a flow-through fish farming system

European and Hungarian fish consumption has been increasing for years. Intensive fish production is one potential methods to meet the ever-increasing demand of Hungarian consumers. However, for the sustainable growth of production, it is necessary to tackle one of the important problems of this type of fish production: reducing the nutrient content of the effluent water. Wetland can be a perfect application to solve the problem. In this research, we examine the efficiency of wastewater treatment in a fish farm where the effluent feeds the Szarvas-Békésszentandrás oxbow system. The current theoretical nutrient retention capacity of the wetland—based on literary data—is 53–61% for nitrogen (N), 76–84% for phosphorus (P) and 80– 91% for chemical oxygen demand (COD). In recent years, the production capacity of the plant has increased to 500 T/year and a new pre-settling and drum filter were added to the filtration, and thus the deterrent effect of the filtration system in 2014–2017 was 74% for "N", 63% for phosphorus and 83% for COD. The efficiency of the wetland was demonstrated by measurements carried out by an accredited independent laboratory proving that no limit value has been exceeded for the last 15 times. We can conclude that the wetland is able to carry out its tasks in the long term, independently of the season, and to ensure that effluent water does not pose a significant impact to the natural environment

CLASSIFICATION OF TIME SERIES VIA WAVELET SUBBAND ANALYSIS USING SUPPORT VECTOR MACHINE CLASSIFIER

An improved feature extraction method has been developed for classification and identification of time series, in case of the number of the experiments are considerably less than that of the samples in time series. The method based on the subband analysis of the wavelet transformation of the time signals, provides lower dimension feature vectors as well as much more robust kernel-based classifier than the traditional wavelet-based feature extraction method does. The application of this technique is illustrated by the classification of cerebral blood flow oscillation using support vector classifier with Gaussian kernel. The computations were carried out with Mathematica 5.1 and its Wavelet Application

Processing Stabilisation of PE with a Natural Antioxidant, Curcumin

The potential use of natural antioxidants for polyolefin stabilisation came into the centre of attention because of some doubts about the effects of the reaction products of synthetic phenolic antioxidants on human health. The effect of curcumin on the melt stability of polyethylene was investigated in this paper with and without a phosphonite stabiliser by using multiple extrusions. Irganox 1010 was applied as reference phenolic antioxidant. Curcumin was characterised by FT-IR and UV-VIS spectroscopy, as well as by thermal analysis. Its stabilisation efficiency was determined by measuring the chemical structure, the rheological properties, the residual thermo-oxidative stability, and the colour of the polymer. The results reveal that the melt stabilising efficiency of curcumin is superior to that of the synthetic antioxidant investigated and is further enhanced by the addition of the phosphonite secondary antioxidant. The changes in the characteristics of the polymer indicate that besides the phenolic OH groups also the linear linkage between the two methoxyphenyl rings of curcumin participates in the stabilisation reactions

A fenntarthatósági szempontok érvényesülése a paksi atomerőmű bővítése kapcsán

Három szakmai műhely, a Budapesti Corvinus Egyetem Stratégiai és Nemzetközi Menedzsment Kutatóközpontja, az Óbudai Egyetem Villamosenergetikai Intézete Megújuló Energiaforrás Kutatóhelye valamint az Eötvös Loránd Tudományegyetem Környezet- és Tájföldrajzi Tanszéke energiagazdálkodással foglalkozó kutatói egyetemközi munkacsoportot hoztak létre annak feltérképezésére, hogy milyen módon fedezhető fenntartható módszerekkel hazánk energiaellátása. Meggyőződésünk, hogy a stratégiai tervezési feladat komplexitása megköveteli az interdiszciplináris közelítésmódot, amely az energetika és a környezetgazdálkodás értő művelői mellett a társadalomtudományok területén dolgozó szakértők bevonását is szükségessé teszi a közeli jövőben. A közelmúlt eseményei a munkacsoport vizsgálódásának fókuszát az új paksi atomerőmű építésének hosszú távú következményeire irányították, hiszen a paksi erőmű bővítése nem kizárólagos opció, csak egy változat a lehetséges energiaellátási megoldások közül. Az eddig felszínre került elsődleges kutatási eredményeink az alábbiakban foglalhatók össze: Számos műszakilag elképzelhető alternatíva létezik Magyarország villamos energia ellátásának tekintetében. Műszakilag megvalósítható akár a tisztán hazai szén alapú, tisztán gáz alapú villamosenergia-termelés, de üzemképes a jelenlegi portfólió is. Hasonlóképpen a nukleáris vagy éppen a megújuló részarány növelése is elképzelhető. Ugyanakkor látni kell, hogy az energiatervezést nem egyszerűsíthetjük le pusztán technikai, műszaki vonatkozások vizsgálatára

Object-based attentional selection modulates anticipatory alpha oscillations

Visual cortical alpha oscillations are involved in attentional gating of incoming visual information. It has been shown that spatial and feature-based attentional selection result in increased alpha oscillations over the cortical regions representing sensory input originating from the unattended visual field and task-irrelevant visual features, respectively. However, whether attentional gating in the case of object based selection is also associated with alpha oscillations has not been investigated before. Here we measured anticipatory electroencephalography (EEG) alpha oscillations while participants were cued to attend to foveal face or word stimuli, the processing of which is known to have right and left hemispheric lateralization, respectively. The results revealed that in the case of simultaneously displayed, overlapping face and word stimuli, attending to the words led to increased power of parieto-occipital alpha oscillations over the right hemisphere as compared to when faces were attended. This object category-specific modulation of the hemispheric lateralization of anticipatory alpha oscillations was maintained during sustained attentional selection of sequentially presented face and word stimuli. These results imply that in the case of object-based attentional selection—similarly to spatial and feature-based attention—gating of visual information processing might involve visual cortical alpha oscillations