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Number of results: 6
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Abstract

Biological diversity within a mixture field allows for better use of habitat and agro-technical conditions by the mixtures, which can be seen by higher and more stable yields than varieties sown separately. Our studies were conducted in the growing seasons 2011/2012–2014/2015 as field experiments with four winter barley varieties (Bombaj, Gil, Gregor, Bażant) and three, two- and three-component mixtures (Bombaj/Gil, Bombaj/Gregor, Gil/Gregor/Bażant). Seven different chemical treatments with fungicides were applied. The aim of this study was to compare the different varieties of winter barley with their mixtures for resistance to powdery mildew infection. To achieve this aim the logistic model for the analysis of data was used. Of the varieties under consideration, the best and the most resistant variety was Gregor, while the weakest and the most susceptible to diseases (powdery mildew) was Gil. This variety was also significantly weaker than any of the other mixtures taken into account. Moreover, it was so weak that when it was included in mixtures with other varieties, it weakened these mixtures as well.

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Authors and Affiliations

Ewa Bakinowska
Anna Tratwal
ORCID: ORCID
Kamila Nowosad
Jan Bocianowski
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Abstract

In this study the formation of the polygenetic High Tatra granitoid magma is discussed. Felsic and mafic magma mixing and mingling processes occurred in all magma batches composing the pluton and are documented by the typical textural assemblages, which include: mafic microgranular enclaves (MME), mafic clots, felsic clots, quartz-plagioclase-titanite ocelli, biotite-quartz ocelli, poikilitic plagioclase crystals, chemically zoned K-feldspar phenocrysts with inclusion zones and calcic spikes in zoned plagioclase. Geochemical modelling indicates the predominance of the felsic component in subsequent magma batches, however, the mantle origin of the admixed magma input is suggested on the basis of geochemical and Rb-Sr, Sm-Nd and Pb isotopic data. Magma mixing is considered to be a first-order magmatic process, causing the magma diversification. The cumulate formation and the squeezing of remnant melt by filter pressing points to fractional crystallization acting as a second-order magmatic process.

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Authors and Affiliations

Aleksandra Gawęda
Krzysztof Szopa
Roman Włodyka
Jolanta Burda
Quentin Crowley
Magdalena Sikorska
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Abstract

Cumulative blasts are an important controlled blasting method used to control the propagation of cracks in the predetermined direction. However, traditional cumulative blasts are associated with long processing times and poor blasting effects. A simple blasting technology called bilateral cumulative tensile explosion (BCTE) is proposed in this paper. There are two application types where BCTE is used. The first application is used to control the stability of high-stress roadways in both Wangzhuang mine 6208 tailgate and Hongqinghe mine 3-1103 tailgate. The second application is used to replace the backfill body in gob-side entry retaining (GER) in Chengjiao mine 21404 panel, Jinfeng mine 011810 panel and Zhongxing mine 1200 panel. The first application type reveals that BCTE can significantly reduce the deformation of the surrounding rock and reduce the associated maintenance cost of the roadways. Whereas the second application type, the roadway deformations are smaller, the process is simpler, and the production costs are lower, which further promotes GER and is of significance towards conserving resources.
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Bibliography

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Authors and Affiliations

Jun Yang
1
ORCID: ORCID
Binhui Liu
1
ORCID: ORCID
Wenhui Bian
1
ORCID: ORCID
Kuikui Chen
1
ORCID: ORCID
Hongyu Wang
1
ORCID: ORCID
Chen Cao
2
ORCID: ORCID

  1. China University of Mining and Technology, State Key Laboratory for Geomechanics and Deep Underground Engineering, Beijing 100083, China
  2. University of Wollongong, Mining & Environment Engineering, School of Civil, Wollongong, NSW 2522, Australia
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Abstract

The aim of this work is to present new reliability characteristics expressed as functions of some variable expressing the measure of effective operation of a machine or a device. These characteristics can be used for both renewable and non-renewable objects. Their mathematical idea reflects the essence of already known characteristics, i.e. it expresses the probability of failure but expressed as a function of a variable, not necessarily identified with time.
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Authors and Affiliations

Gabriela Kopania
Anna Kuczmaszewska
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Abstract

Today, foundries are facing increasing demands for greener and more economical production while maintaining or improving the quality of the castings produced. The importance and use of green sand mixtures using bentonite as a binder are thus coming to the fore once again. They have the advantage of both eliminating the chemicalization of production and also allowing the immediate use of the already used mixture, including the binder, after adjustment of the composition and mulling. In order to maintain the quality of the resulting castings, it is necessary to monitor the properties of the moulding mixture through a series of laboratory tests. It is also essential to look at the processing quality of these mixtures, i.e. the combination of good mulling quality and efficient mulling time, which is often neglected. It is the quality of mulling and the effective mulling time that help to develop the bonding properties of the bentonite, improve the properties of the mixture, determine the efficiency of the muller and possibly reduce the time and energy required for mulling. The aim of this work is to present the effect of mulling on the properties of sand-water-bentonite mixtures. The properties studied are mainly the compactability, strength characteristics, moisture content of the mixture and the order of addition of raw materials.
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Bibliography

[1] Jelínek, P. & Mikšovský, F. (1985). Contribution to the evaluation of the efficiency of uniform green moulding mixture. Slévárenství. XXXIII (7), 268-274. (in Czech)
[2] Troy, E.C. et al. (1971). A Mulling Index Applied to Sand-water-bentonite. AFS Transactions. 79, 213-224.
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Authors and Affiliations

M. Gawronová
1
ORCID: ORCID
Š. Kielar
1
P. Lichý
1
ORCID: ORCID

  1. VSB-Technical University of Ostrava, Faculty of Materials Science and Technology, Department of Metallurgical Technologies, Czech Republic
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Abstract

During archaeological excavation conducted in 2017 between the streets of St. Katarzyna, St. Wit, Wit Stwosz and Nowy Targ Square in Wrocław 46 numismatic objects were discovered – 37 coins, 4 jetons, 4 objects related to numismatics (silver planchet, a small piece of cast silver and two containers for bracteates – one lid and one bottom, from various containers) and one lead token. Early medieval, late medieval and early modern coins appeared. The most interesting are the thirteenth-century Silesian bracteates of the Ratajski and Kałowice types. During excavation a rare Prague parvus of Wenceslas II was also found. Among all the coins, one of the most interesting is counterfeited West Pomeranian denier of Bogusław I, Duke of Pomerania. All analyzed coins constitute a cumulative find that was found in one of Wrocław’s auxiliary markets of medieval origin.
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Authors and Affiliations

Paweł Milejski
1
ORCID: ORCID

  1. Dział Numizmatyczny, Muzeum Książąt Lubomirskich, Zakład Narodowy im. Ossolińskich we Wrocławiu, Szewska 37, 50-139 Wrocław

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