21 research outputs found

    The losses and efficiency determination for three-phase, squirrel-cage induction motors - new requirements of standards

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    W pracy przedstawiono metodę wyznaczania strat i sprawności silników indukcyjnych klatkowych według normy polskiej PN-EN 60034-2-1:2008. Podano wymagania dotyczące dokładności przyrządów, procedurę przeprowadzania badań oraz wyznaczania wartości strat i sprawności. Zwrócono uwagę na nowe elementy wprowadzone w procedurze obliczania strat i sprawności wpływające na dokładność wyznaczania sprawności.The paper presents losses and efficiency determination method in squirrel-cage induction motors according to the Polish Standard PN-EN 60034-2-1:2008. The requirements of measuring instruments accuracy, testing procedure and method of losses and efficiency determination were presented. Take notice to new elements in procedure of calculation losses and efficiency which have influence on accuracy of efficiency determination

    Obliczenie strat za pomocą metody elementów skończonych

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    In this study, the authors have concentrated to a cage-induction motor. They compare the loss calculations by FEM (Finite Element Method) magnetic field analyser with the loss measurements made by calorimetric chamber. The FEM program has its problems of working. The material properties and the manufacturing tolerances has to be taken into account using correction factors to the material properties of electric sheets, the current losses are solved by time stepping method and together with the magnetic field solution, but the iron losses are solved after the field analysis. The iron losses have no feedback to the field analysis. At no-load calculations, the cage-induction motor has to have a non-zero slip.W artykule autorzy porównali różne metody określania strat silnika indukcyjnego klatkowego. Porównano straty obliczone metodą FEM (Finite Element Method - Metoda Elementów Skończonych) analizy pola magnetycznego z wynikami pomiaru strat metodą kalorymetryczną. Przedstawiono rozwiązanie problemów występują-cych w programie obliczeniowym. Własności materiałów oraz tolerancje zostały uwzględnione w obliczeniach za pomocą współczynników dla materiału blach. W programie FEM straty w uzwojeniu obliczano jednocześnie z analizą pola mag-netycznego. Straty w żelazie obliczano po przeprowadzeniu analizy pola. W obliczeniach dla biegu jałowego silnika indukcyjnego klatkowego przyjęto, że poślizg nie jest równy zero

    The measurement of machines winding resistance in run

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    Jedną z prób wykonywanych podczas badań silników indukcyjnych jest wyznaczenie przyrostu temperatury uzwojenia stojana pracującej maszyny. W referacie przedstawiono metodę pomiaru tej wielkości, oraz opis modelu skonstruowanego do tego celu przyrządu. Zamieszczono również wyniki badań porównawczych prezentowanego modelu przyrządu i dotychczas stosowanego w Laboratorium Zakładu Maszyn mostka MTME-101.This article present the measurement method of the temperature rise of an induction motor winding and description measurement instrument model designed for this purpose. The comparison of laboratory tests mode using presented instrument model and reference instrument MTME - 101 is included in this paper

    The assessment of the degree of iron recovery from mineral wool waste using ethylenediaminetetraacetic acid

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    W pracy przedstawiono wyniki badań ekstrakcji żelaza z odpadowej wełny mineralnej stosowanej w uprawach hydroponicznych. W badaniach jako ekstrahent wykorzystano wodę i EDTA. Wełna mineralna jest podłożem inertnym wykorzystywanym w uprawach pod osłonami. Obecnie aspekty ekonomiczne, środowiskowe, a także wzrost zapotrzebowania na produkty żywnościowe sprawiają, że klasyczne metody upraw warzyw i kwiatów są niewystarczające. Większa produkcja warzyw i roślin ozdobnych możliwa jest w warunkach bezglebowych z zastosowaniem wełny mineralnej. Metoda uprawy na podłożu z wełny mineralnej stanowi jednak dodatkowy problem środowiskowy związany z utylizacją odpadu, którym jest poprodukcyjna wełna mineralna. Poprodukcyjna wełna mineralna zawiera pewne ilości cennych mikroelementów wykorzystywanych w uprawie roślin. Koszt komponentów wykorzystywanych w pożywkach jest wysoki. Sprawia to, że ekstrakcja wybranych składników pokarmowych odpowiednio dobranymi ekstrahentami i opracowanie nowego produktu nawozowego staje się interesującym rozwiązaniem. Zaproponowany sposób pozyskiwania mikroelementowego żelaza z odpadowej wełny mineralnej składa się z następujących etapów: suszenia w temperaturze 30°C w czasie 24 h w celu usunięcia zawartości wody, rozdrabniania i wyodrębnienia frakcji cząstek o wymiarach 0,40 mm, ekstrakcji składników pokarmowych i rozdziału faz. Jako ekstrahent mikroelementów nawozowych w przedstawionych badaniach zastosowano wodę i roztwór EDTA. W badaniach uwzględniono wpływ czasu i temperatury na skuteczność prowadzonego procesu. W otrzymanej fazie ciekłej, oddzielonej po ekstrakcji metodą wirowania, analizowano zawartość żelaza. Zawartość żelaza w fazie ciekłej oznaczono metodą fotokolorymetryczną z wytworzeniem barwnego kompleksu jonów żelazowych z 2,2-pirydylem w roztworze o pH = 3,1.This paper presents the results of extraction of iron from waste mineral wool used in hydroponics. In this studies as extractant was used water and EDTA. Mineral wool is an inert substrate used in crops under cover. Currently, economic, environmental, and increasing demand for food products make that the classic methods of growing vegetables and flowers are insufficient. Increased production of vegetables and ornamentals is possible under soilless mineral wool. However, the method of cultivation on mineral wool substrate is, an additional environmental problem associated with the disposal of waste, which is a thorough wool. Post-production mineral wool contains some valuable micronutrients used in the cultivation of plants. The cost of components used in the media is high. This makes that the extraction of selected nutrients by using appropriately selected extraction reagents becomes an interesting solution to develop a new fertilizer product. The proposed way to obtain the iron from the mineral wool waste consists of the following steps: drying at 30°C for 24 hours - to remove water content, grinding and separation of the fraction of particles with dimensions of 0.40 mm, nutrient extraction and phase separation. As extractant of fertilizer micronutrient in the tests was used water and the solution of EDTA. The study tested the effect of time and temperature on the efficiency of the process. The iron content was analyzed in the liquid phase separated after the extraction by centrifugation. The iron content was analyzed by spectrophotometric method based on formation of a colored ferric ion complex of 2,2-pyridyl in solution at pH = 3.1

    Porównanie skuteczności wykorzystania różnego typu ekstrahentów do odzysku żelaza z odpadowej wełny mineralnej

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    The paper presents the results of iron extraction from wool waste. In studies as extractant was used: water, EDTA, acetic acid, formic acid, DTPA, ammonium lactate and calcium lactate. For analysis has been taken wool after one year cultivation of tomato and cucumber and wool after two years of mixed cultivation. The main aim of the analysis was to determine which extractant allows the greatest recovery of the iron from waste mineral wool. Current trends in the agriculture development and the fertilizer industry are aimed at maximizing the recovery of nutrients from waste for re-use. Demonstration of the effectiveness of the recycling of valuable trace elements contained in the mineral wool can make develop a method of wool utilization profitable. In addition, the high cost of fertilizer components makes a new type of medium containing nutrients obtained by extraction from mineral wool waste, can be an interesting option in the future. Implementation of this type of process is consistent with the objectives of Sustainable Development, as well as the environmental policy of the European Union. The proposed way to get iron from mineral waste wool consists of following steps: drying at 30 oC for 24 hours, grinding to particles with a sieve size of 0.40 nm, extraction and phase separation. The studies included the effect of time, temperature and type of extractants on the efficiency of the process. The iron content in the samples was determined by spectrophotometric method based on the ferric ion complex of 2,2-pyridyl in a solution at pH of 3.1.W pracy zostały przedstawione wyniki ekstrakcji żelaza z odpadowej wełny mineralnej. W badaniach jako ekstrahenty wykorzystano: wodę, roztwór EDTA, kwas octowy, kwas mrówkowy, DTPA, mleczan amonu i mleczan wapnia. Analizie została poddana wełna jednoroczna po uprawie pomidora i ogórka, a także dwuletnia po uprawie mieszanej. Głównym celem analizy było określenie, który ekstrahent umożliwia największy odzysk żelaza z poprodukcyjnej wełny ogrodniczej. Obecne tendencje rozwoju rolnictwa, jak i przemysłu nawozowego są skierowane na maksymalizowanie odzysku składników odżywczych z odpadów, w celu ich powtórnego wykorzystania. Wykazanie skuteczności recyklingu cennych mikrślementów zawartych w wełnie mineralnej może pozwolić na opracowanie opłacalnej metody utylizacji tego odpadu. Ponadto wysoki koszt komponentów nawozowych sprawia, że nowy typ pożywki zawierający składniki pokarmowe pozyskane na drodze ekstrakcji z odpadowej wełny mineralnej może być w przyszłości interesującym rozwiązaniem. Wdrożenie tego typu procesów jest zgodne z założeniami Zrównoważonego Rozwoju, a także polityką ochrony środowiska Unii Europejskiej. Mikrślementowe żelazo pozyskiwane było z odpadowej wełny na drodze: suszenia w temperaturze 30 oC przez 24 h, rozdrabniania na sicie na cząsteczki o wymiarach 0,40 nm, ekstrakcji i rozdziału faz. W prowadzonych badaniach analizie poddano wpływ czasu ekstrakcji, temperatury, a także rodzaju stosowanego ekstrahenta. Zawartość żelaza w próbkach oznaczano metodą fotokolorymetryczną z wytworzeniem kompleksu jonów żelazowych z 2,2-pirydylem w roztworze o pH wynoszącym 3,1

    Relationship Between Anti-DFS70 Autoantibodies and Oxidative Stress

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    Background: The anti-DFS70 autoantibodies are one of the most commonly and widely described agent of unknown clinical significance, frequently detected in healthy individuals. It is not known whether the DFS70 autoantibodies are protective or pathogenic. One of the factors suspected of inducing the formation of anti-DFS70 antibodies is increased oxidative stress. We evaluated the coexistence of anti-DFS70 antibodies with selected markers of oxidative stress and investigated whether these antibodies could be considered as indirect markers of oxidative stress. Methods: The intensity of oxidative stress was measured in all samples via indices of free-radical damage to lipids and proteins such as total oxidant status (TOS), concentrations of lipid hydroperoxides (LPH), lipofuscin (LPS), and malondialdehyde (MDA). The parameters of the non-enzymatic antioxidant system, such as total antioxidant status (TAS) and uric acid concentration (UA), were also measured, as well as the activity of superoxide dismutase (SOD). Based on TOS and TAS values, the oxidative stress index (OSI) was calculated. All samples were also tested with indirect immunofluorescence assay (IFA) and 357 samples were selected for direct monospecific anti DFS70 enzyme-linked immunosorbent assay (ELISA) testing. Results:: The anti-DFS70 antibodies were confirmed by ELISA test in 21.29% of samples. Compared with anti-DFS70 negative samples we observed 23% lower concentration of LPH (P = .038) and 11% lower concentration of UA (P = .005). TOS was 20% lower (P = .014). The activity of SOD was up to 5% higher (P = .037). The Pearson correlation showed weak negative correlation for LPH, UA, and TOS and a weak positive correlation for SOD activity. Conclusion: In samples positive for the anti-DFS70 antibody a decreased level of oxidative stress was observed, especially in the case of samples with a high antibody titer. Anti-DFS70 antibodies can be considered as an indirect marker of reduced oxidative stress or a marker indicating the recent intensification of antioxidant processes

    Lipid levels, atrial fibrillation and the impact of age: Results from the LIPIDOGRAM2015 study

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    Analysis of the impact of sex and age on the variation in the prevalence of antinuclear autoantibodies in Polish population:a nationwide observational, cross-sectional study

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    The detection of antinuclear autoantibody (ANA) is dependent on many factors and varies between the populations. The aim of the study was first to assess the prevalence of ANA in the Polish adult population depending on age, sex and the cutoff threshold used for the results obtained. Second, we estimated the occurrence of individual types of ANA-staining patterns. We tested 1731 patient samples using commercially available IIFA using two cutoff thresholds of 1:100 and 1:160. We found ANA in 260 participants (15.0%), but the percentage of positive results strongly depended on the cutoff level. For a cutoff threshold 1:100, the positive population was 19.5% and for the 1:160 cutoff threshold, it was 11.7%. The most prevalent ANA-staining pattern was AC-2 Dense Fine speckled (50%), followed by AC-21 Reticular/AMA (14.38%) ANA more common in women (72%); 64% of ANA-positive patients were over 50 years of age. ANA prevalence in the Polish population is at a level observed in other highly developed countries and is more prevalent in women and elderly individuals. To reduce the number of positive results released, we suggest that Polish laboratories should set 1:160 as the cutoff threshold.</p

    Metabolic syndrome is associated with similar long-term prognosis in non-obese and obese patients. An analysis of 45 615 patients from the nationwide LIPIDOGRAM 2004-2015 cohort studies

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    Aims We aimed to evaluate the association between metabolic syndrome (MetS) and long-term all-cause mortality. Methods The LIPIDOGRAM studies were carried out in the primary care in Poland in 2004, 2006 and 2015. MetS was diagnosed based on the National Cholesterol Education Program, Adult Treatment Panel III (NCEP/ATP III) and Joint Interim Statement (JIS) criteria. The cohort was divided into four groups: non-obese patients without MetS, obese patients without MetS, non-obese patients with MetS and obese patients with MetS. Differences in all-cause mortality was analyzed using Kaplan-Meier and Cox regression analyses. Results 45,615 participants were enrolled (mean age 56.3, standard deviation: 11.8 years; 61.7% female). MetS was diagnosed in 14,202 (31%) by NCEP/ATP III criteria, and 17,216 (37.7%) by JIS criteria. Follow-up was available for 44,620 (97.8%, median duration 15.3 years) patients. MetS was associated with increased mortality risk among the obese (hazard ratio, HR: 1.88 [95% CI, 1.79-1.99] and HR: 1.93 [95% CI 1.82-2.04], according to NCEP/ATP III and JIS criteria, respectively) and non-obese individuals (HR: 2.11 [95% CI 1.85-2.40] and 1.7 [95% CI, 1.56-1.85] according to NCEP/ATP III and JIS criteria respectively). Obese patients without MetS had a higher mortality risk than non-obese patients without MetS (HR: 1.16 [95% CI 1.10-1.23] and HR: 1.22 [95%CI 1.15-1.30], respectively in subgroups with NCEP/ATP III and JIS criteria applied). Conclusions MetS is associated with increased all-cause mortality risk in non-obese and obese patients. In patients without MetS obesity remains significantly associated with mortality. The concept of metabolically healthy obesity should be revised

    Surgery and outcome of infective endocarditis in octogenarians: prospective data from the ESC EORP EURO-ENDO registry

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    Purpose: High mortality and a limited performance of valvular surgery are typical features of infective endocarditis (IE) in octogenarians, even though surgical treatment is a major determinant of a successful outcome in IE. Methods: Data from the prospective multicentre ESC EORP EURO-ENDO registry were used to assess the prognostic role of valvular surgery depending on age. Results: As compared to &lt; 80&nbsp;yo patients, ≥ 80&nbsp;yo had lower rates of theoretical indication for valvular surgery (49.1% vs. 60.3%, p &lt; 0.001), of surgery performed (37.0% vs. 75.5%, p &lt; 0.001), and a higher in-hospital (25.9% vs. 15.8%, p &lt; 0.001) and 1-year mortality (41.3% vs. 22.2%, p &lt; 0.001). By multivariable analysis, age per se was not predictive of 1-year mortality, but lack of surgical procedures when indicated was strongly predictive (HR 2.98 [2.43–3.66]). By propensity analysis, 304 ≥ 80&nbsp;yo were matched to 608 &lt; 80&nbsp;yo patients. Propensity analysis confirmed the lower rate of indication for valvular surgery (51.3% vs. 57.2%, p = 0.031) and of surgery performed (35.3% vs. 68.4%, p &lt; 0.0001) in ≥ 80&nbsp;yo. Overall mortality remained higher in ≥ 80&nbsp;yo (in-hospital: HR 1.50[1.06–2.13], p = 0.0210; 1-yr: HR 1.58[1.21–2.05], p = 0.0006), but was not different from that of &lt; 80&nbsp;yo among those who had surgery (in-hospital: 19.7% vs. 20.0%, p = 0.4236; 1-year: 27.3% vs. 25.5%, p = 0.7176). Conclusion: Although mortality rates are consistently higher in ≥ 80&nbsp;yo patients than in &lt; 80&nbsp;yo patients in the general population, mortality of surgery in ≥ 80&nbsp;yo is similar to &lt; 80&nbsp;yo after matching patients. These results confirm the importance of a better recognition of surgical indication and of an increased performance of surgery in ≥ 80&nbsp;yo patients
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