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Abstrakt

The present study was conducted to evaluate the insecticidal efficiency and safety of zinc oxide nanoparticles (ZnO NPs) and hydrophilic silica nanoparticles (SiO2 NPs) against: adults of rice weevil (Sitophilus oryzae L.); red flour beetle (Tribolium castaneum Herbst.) and cowpea beetle (Callosobruchus maculatus F.) results showed that, both ZnO NPs and hydrophilic SiO2 NPs exhibited a significant toxic effect (df, F and p < 0.5) against S. oryzae and C. maculatus at the highest concentration while T. castaneum showed high resistance against the two tested materials. At the end of the experiment, recorded mortality was: 81.6, 98.3 and 58.3% at the highest concentration used for each insect (0.3, 2 and 8 gm ⋅ kg–1 of SNPs with C. maculatus, S. oryzae and T. castaneum, respectively), while mortality was 88.3, 100 and 38.3% at the highest concentration used for each insect (0.6, 2.5 and 8 gm ⋅ kg–1 of ZnO NPs with C. maculatus, S. oryzae and T. castaneum, respectively). Both tested materials caused high reductions in F1-progeny (%) with C. maculatus and S. oryzae. Histopathological examination of male mice livers showed hepatic architecture with congested blood sinusoids, binucleated hepatocytes nuclei, dilated central vein and margainated chromatin in some nuclei. Histopathological assessment of the lungs showed normal histoarchitecture. There were no differences in alveolar septa, bronchiolar and epithelium of the treated and untreated animals. Silica and zinc oxide nanoparticles have a good potential to be used as stored seed protectant alternatives if applied with proper safety precautions.

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Autorzy i Afiliacje

Samia Ali Haroun
Mahmoud Elsaid Elnaggar
Doaa Mohamed Zein
Rehab Ibrahim Gad

Abstrakt

In conventional finite element simulations, foil windings with thin foils and with a large number of turns require many mesh elements. This renders models quickly computationally infeasible. This paper uses a homogenized foil winding model and approximates the voltage distribution in the foil winding domain by globally supported polynomials. This way, the small-scale structure in the foil winding domain does not have to be resolved by the finite element mesh. The method is validated successfully for a stand-alone foil winding example and for a pot inductor example. Moreover, a transformer equipped with a foil winding at its primary side is simulated using a field-circuit coupled model.
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Autorzy i Afiliacje

Jonas Bundschuh
1 2
ORCID: ORCID
Yvonne Späck-Leigsnering
1 2
ORCID: ORCID
Herbert De Gersem
1 2
ORCID: ORCID

  1. Institute for Accelerator Science and Electromagnetic Fields (TEMF) Technical University of Darmstadt Schloßgartenstraße 8, 64289 Darmstadt, Germany
  2. Graduate School of Excellence Computational Engineering Technical University of Darmstadt Dolivostraße 15, 64293 Darmstadt, Germany

Abstrakt

In 1999-2001 the occurrence of thrips was analysed on seven cultivars of pea. The samples of leaves, then leaves and flower buds and the flowers were collected from plots. The analyses were initiated when the earliest cultivar (Sześciotygodniowy) began flowering and were repeated every 4-7 days, until the end of flowering. The following species of th rips were found: Franklinie/la intonsa Trybom, Thrips major Uzel, Thrips fuscipennis Hal., Thrips tabaci Lind. and Kakothrips robustus Uzel. The clear differences between the number of thrips on the particular cul tivars of pea were noticed. The most attractive were late cultivars Nike and Telefon as well as middle late Delisa II. It seems that the most important factor effecting on the number of thrips on particular cultivars was rather the start and the end of flowering than the length of the flowering period. The greatest number of thrips was noticed on flowers, from 50% to 77%. The thrips initially were found on leaves and then, as the pea was growing, on the flower buds and flowers. After the emergence of thrips, the analyses should be first initiated on leaves.
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Autorzy i Afiliacje

Andrzej Wnuk
Maria Pobożniak

Abstrakt

Under former maritime legislation, breaching the regulations established by this legislation was considered a crime or a misdemeanor. The punishment for the latter was usually a money fine. From 1991, this kind of action was punishable by so-called financial penalties, imposed by administrative decision (in administrative procedure) by the local organs of the maritime administration. The present normalization of this material raises a host o f objections. This article discusses this process o f normalization, and casts doubt upon its legality and constitutionality.

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Autorzy i Afiliacje

Zbigniew Godecki

Abstrakt

Bromiany są dobrze znanymi ubocznymi produktami tworzącymi się podczas ozonowania wód; ich dopuszczalne stężenie w wodach do picia zostało ustalone na poziomie kilku μg/dm3. Techniką analityczną pozwalającą na oznaczanie tak niskich stężeń bromianów, nawet w obecności wysokich stężeń głównych anionów, takich jak chlorki, azotany i siarczany, jest chromatografia jonowa. Niniejszy artykuł przedstawia wyniki oznaczania bromianów w wodach do picia za pomocą dwóch metod chromatografii jonowej. Pierwszą była metoda bezpośrednia, zgodna z ISO 15061 z detektorem konduktometrycznym i granicą wykrywalności 4,5 μg/dm3. Drugą metodą była nowa reakcja derywatyzacji po kolumnie, w której wytwarzane jony tribromkowe były wykrywane za pomocą detektora UV. Granica wykrywalności w tej metodzie wyniosła 0,5 μg/dm3. Obydwie metody są odpowiednie do oznaczania anionów bromianowych, ponieważ dopuszczalna zawartość bromianów w wodach do picia w krajach Unii Europejskiej wynosi 10 μg/dm3•
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Autorzy i Afiliacje

Rajmund Michalski

Abstrakt

In this study, it was achieved by using the method of impulse noise to detect internal or surface cracks that can occur in the production of ceramic plates. Ceramic materials are often used in the industry, especially as kitchenware and in areas such as the construction sector. Many different methods are used in the quality assurance processes of ceramic materials. In this study, the impact noise method was examined. This method is a test technique that was not used in applications. The method is presented as an examination technique based on whether there is a deformation on the material according to the sound coming from it as a result of a plastic bit hammer impact on the ceramic material. The application of the study was performed on plates made of ceramic materials. Here, it was made with the same type of model plates manufactured from the same material. The noise that would occur as a result of the impact applied on a point determined on the materials to be tested has been examined by the method of time-frequency analysis. The method applied gives pretty good results for distinguishing ceramic plates in good condition from those which are cracked.

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Autorzy i Afiliacje

Tahir Akinci

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