53 research outputs found

    Influence of structural changes of Co78Si9B13 metallic glass on magnetic properties

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    The primary crystallization of Co78Si9B13 metallic glass starts at 648 K and as a consequence of this the Δ-Co(Si) phase with needle morphology is created. The second stage of crystallization (at 773 K) is the eutectic and as a result of this α-Co(Si) and boron phases: (Co,Si)3B, (Co,Si)2B are formed. The crystallites of these phases have layer morphology. These characteristic morphologies in the first and second stages lead to the increase in coercivity

    The role of research in global food and nutrition security

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    The present discussion document gives an overview of where European research can add the most value in relation to tackling food and nutrition security challenges and points to areas where we can expand our research potential. Moreover, it highlights the need to develop a governance structure that will allow sharing of best practices and facilitate the transfer of knowledge and innovation to feed the planet sustainably. It should stimulate a global discussion with stakeholders and the general public, ultimately shaping a legacy for Expo 2015.JRC.A.TF-EXPO 201

    High Power Factor Nb-Doped TiO2 Thermoelectric Thick Films : Toward Atomic Scale Defect Engineering of Crystallographic Shear Structures

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    Donor-doped TiO 2-based materials are promising thermoelectrics (TEs) due to their low cost and high stability at elevated temperatures. Herein, high-performance Nb-doped TiO 2 thick films are fabricated by facile and scalable screen-printing techniques. Enhanced TE performance has been achieved by forming high-density crystallographic shear (CS) structures. All films exhibit the same matrix rutile structure but contain different nano-sized defect structures. Typically, in films with low Nb content, high concentrations of oxygen-deficient {121} CS planes are formed, while in films with high Nb content, a high density of twin boundaries are found. Through the use of strongly reducing atmospheres, a novel Al-segregated {210} CS structure is formed in films with higher Nb content. By advanced aberration-corrected scanning transmission electron microscopy techniques, we reveal the nature of the {210} CS structure at the nano-scale. These CS structures contain abundant oxygen vacancies and are believed to enable energy-filtering effects, leading to simultaneous enhancement of both the electrical conductivity and Seebeck coefficients. The optimized films exhibit a maximum power factor of 4.3 × 10 -4 W m -1 K -2 at 673 K, the highest value for TiO 2-based TE films at elevated temperatures. Our modulation strategy based on microstructure modification provides a novel route for atomic-level defect engineering which should guide the development of other TE materials

    Innovative medical technologies in the percutaneous treatment of tricuspid regurgitation in Poland

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    Tricuspid regurgitation (TR) usually develops secondarily to left-sided heart diseases, whereas primary lesions to the valve apparatus is less common. Untreated severe TR has a poor prognosis and surgical treatment, i.e., valve repair or replacement, is the only treatment option with class I recommendation. However, cardiac surgical procedures may be associated with a high risk of complications. Recent advances in percutaneous approaches to managing structural heart diseases, especially mitral valve diseases, have enabled the implementation of this therapeutic strategy in the population of patients with TR. This paper presents data on the clinical efficacy, cost-effectiveness and expected population size for one of these procedures, namely the TriClip TTVr System procedure. Its efficacy was assessed in the TRILUMINATE study involving 85 patients with co-morbidities and at high surgical risk. After 1 year of follow-up, the reduction in the TR grade was reported in 71% of patients. Clinical improvement in New York Heart Association functional class, a 6-minute walk test, and the quality of life were also observed. A published analysis comparing percutaneous treatment modalities with a drug therapy based on data from medical registers was utilized, and propensity score matching was also employed. Percutaneous treatment reduced 1-year mortality and rehospitalisation risk. The economic analysis showed the use of TriClip TTVr System is cost-effective: the cost of an additional quality-adjusted life year ranged from approximately PLN 85,000 to PLN 100,000, which is below the official threshold in Poland. The potential annual number of candidates for this treatment modality in Poland is estimated at 265

    Home enteral nutrition in children—2010 nationwide survey of the polish society for clinical nutrition of children

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    Published epidemiologic data on the administration rates of enteral/parenteral home nutrition is very limited. The aim of this first nationwide study was to assess the availability of pediatric home enteral nutrition (HEN) services in Poland. The questionnaire was sent to all regional centers providing pediatric HEN services in Poland (n = 14). The analysis included the number of pediatric patients who received HEN in 2010, their demographic characteristics and geographical distribution. Furthermore, the distributions of indications and methods of enteral nutrition administration were analyzed, along with the reasons of withdrawal from the HEN program. The number and fraction of children receiving HEN increased in 2010, from 433 (11.34 per 1 million inhabitants) on January 1st to 525 (13.75) on December 31st. Marked differences were observed in geographical distribution of this parameter, from zero to up to 30 pediatric patients per 1 million inhabitants. Median age of patients was 6 years (range: 9 months–18 years). In most cases, HEN was prescribed due to neurological disorders (n = 337, 64.2%), and administered by means of gastrostomy (n = 450, 85.71%). This study revealed the dynamic development of pediatric HEN services in Poland but also documented their potential regional shortages

    Effect of sodium rich pretreatments and processing conditions on microstructure and property evolution of sodium cobalt oxide thermoelectric materials

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    Global environmental and sustainability issues have led to a growth in interest in oxide based thermoelectric materials. Sodium cobalt oxide, which presents low toxicity, is one of the most promising p-type thermoelectric materials for high temperature power generation applications. However, reproducibility and ease of manufacture limits its common use. NaCo2O4 bulk ceramic materials were prepared from powders synthesized using a solid state reaction (SSR) and sol gel (SG) method. The effect of time and temperature of treatment were investigated in order to determine their influence on microstructure and physical properties. The effects of three different Na-enriching pretreatments were evaluated with respect to microstructural evolution and their impact on thermoelectric and electric behaviour of the materials. Such modifications were found to be a critical factor affecting the microstructure of the bulk ceramic materials. The Na-rich pretreatments were found to improve density by up to 15%, increase electrical conductivity and help to compensate for Na loss at high sintering temperatures. The thermoelectric figure of merit ZT was found to increase for Na-rich pretreatment samples due to increases in Seebeck coefficient and low thermal conductivity. The highest value of ZT was found to be for the infiltration pretreatment where the value of 0.025 was observed at 350K. Na rich pretreatments, when compared with unpretreatment samples, reduces thermal conductivity by up to 35%, electrical resistivity by up to 67%, increases Seebeck coefficient by up to 23% and as a consequence increases ZT for ball milling preatreatment by 28%, for mixing preatreatment by 71% and for infiltrating by 250%. A range of films were also produced using a spin coating technique, with thicknesses ranging from 200 nm, for single sol gel layers, up to ~ 32ÎŒm for 4 (ink + 2 sol layers) structures. Several factors such as: process conditions, substrates, surfactant and base components used, were investigated in order to improve the quality of films. Process conditions were found to be a critical factor affecting the quality of films. The use of sol infiltration of each layer and a higher preheated temperature were found to reduce surface roughness by up to 23%. The films showed good electrical resistivity ranging from 260 to 500 ΌΩcm. The lowest value of electrical resistivity was found to be for films annealed at 700ÂșC

    The Effect of Freeze-Drying on the Properties of Polish Vegetable Soups

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    The aim of this study was to investigate selected physical and biochemical properties of four vegetable freeze-dried soups. The water content, water activity, pH, color parameters, antioxidant activity (EC50), total polyphenolic content of fresh tomato, pumpkin, beetroot, and cucumber, and freeze-dried soups were measured. Sensory analysis was applied to compare sensory attributes of fresh and rehydrated soups. The sorption isotherms of freeze-dried soups were obtained with the application of the static and dynamic vapor sorption (DVS) method. The application of the freeze-drying method enabled the obtaining of dry soups with a low water content of 2–3%. The drying caused a significant change of color of all soups. The redness of soups decreased after drying for the beetroot soups from +39.64 to +21.91. The lower chroma value of 25.98 and the highest total color change ΔE*ab = 36.74 were noted for freeze-dried beetroot soup. The antioxidation activity and total polyphenolic content were reduced after drying, especially for the cucumber and tomato soups. The Peleg model was selected to describe the sorption isotherms of dried soups. The sorption isotherm of freeze-dried cucumber and beetroot soups had a sigmoidal shape of type II. The shape of the moisture sorption isotherm for freeze-dried tomato and pumpkin soups corresponded more with type III isotherms. The DVS method can be used to characterize the moisture sorption isotherms of freeze-dried products

    Extending the functionality and efficiency of energy storage tanks in solar power plants

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    Improvements to the efficiency of Solar Power Plants are a key objective as the technology matures. Oneopportunity yet to be explored involves energy harvesting from hot components located within the powerplant, utilizing waste heat. We describe two approaches to energy harvesting in this context. These are basedfirstly on TEC device technology, where we describe the use of both commercially available components andour work to develop more efficient TEC devices based on nanostructured oxides. Secondly, we describe analternative thermomagnetic approach based on nanoparticle ferrofluids for thermal scavenging and theconversion of heat to usable electrical energy. For both approaches we present concept designs for theharvesting of waste heat from thermal energy storage (TES) tanks, in order to demonstrate the potential of thetechnology

    Effect of Pulsed Electric Field Pre-Treatment and the Freezing Methods on the Kinetics of the Freeze-Drying Process of Apple and Its Selected Physical Properties

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    The aim of this study was to investigate the effect of application of pulsed electric field (PEF) and different freezing methods (fast, slow and vacuum freezing) on the drying kinetics as well as selected physical properties of freeze-dried apple. The apples were subjected to PEF treatment with range of pulses from 0 to 160 and the intake energy from 0 to 1327 kJ·g−1. Apples with and without PEF treatment were frozen with different rates and the freeze-dried. The water content, water activity and colour attributes of freeze-dried apples were investigated. Regression analysis and fitting procedures showed that among six different models, the Midilli et al. model the best described the drying curves of all dried samples. The highest value of the parameter L* = 71.54 was obtained for freeze-dried sample prepared without PEF pre-treatment and fast frozen. Application of PEF pre-treatment resulted in increase in browning index of freeze-dried apples (BI). The studies confirmed the positive effect of PEF on the freeze drying rate only in the case of the slow or fast freezing of the material after the application of low-energy PEF treatment. However, the increase in drying rate was also observed after application of slow and vacuum freezing of the material without PEF pre-treatment. These technologies can be recommended for optimization of the freeze drying process of apples. The statement that the freeze drying process with application of appropriately selected PEF processing parameters causing only partial destruction of cell membranes can be considered as an innovative contribution to the development of science about the possibilities of PEF application

    The Effect of Freeze-Drying on the Properties of Polish Vegetable Soups

    No full text
    The aim of this study was to investigate selected physical and biochemical properties of four vegetable freeze-dried soups. The water content, water activity, pH, color parameters, antioxidant activity (EC50), total polyphenolic content of fresh tomato, pumpkin, beetroot, and cucumber, and freeze-dried soups were measured. Sensory analysis was applied to compare sensory attributes of fresh and rehydrated soups. The sorption isotherms of freeze-dried soups were obtained with the application of the static and dynamic vapor sorption (DVS) method. The application of the freeze-drying method enabled the obtaining of dry soups with a low water content of 2–3%. The drying caused a significant change of color of all soups. The redness of soups decreased after drying for the beetroot soups from +39.64 to +21.91. The lower chroma value of 25.98 and the highest total color change ΔE*ab = 36.74 were noted for freeze-dried beetroot soup. The antioxidation activity and total polyphenolic content were reduced after drying, especially for the cucumber and tomato soups. The Peleg model was selected to describe the sorption isotherms of dried soups. The sorption isotherm of freeze-dried cucumber and beetroot soups had a sigmoidal shape of type II. The shape of the moisture sorption isotherm for freeze-dried tomato and pumpkin soups corresponded more with type III isotherms. The DVS method can be used to characterize the moisture sorption isotherms of freeze-dried products
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