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E. Talik, L. Lipińska, A. Guzik, P. Zajdel, M. Michalska, M. Szubka, M. Kądziołka-Gaweł and R.L. Paul

1 Introduction Lithium manganese oxide (LiMn 2 O 4 ) spinel has been extensively studied as a cathode material for Li-ion batteries, as an alternative to LiCoO 2 , LiNiO 2 or LiFePO 4 used today. Initially, LiMn 2 O 4 spinel has been synthesized mainly using conventional solid state methods [ 1 , 2 ]. Nowadays, other synthetic routes are applied too. One of them is a modified sol-gel (Pechini) technique, which seems to be appropriate for preparation of nanocrystalline cathode materials. Being a solution-based route, it offers a possibility of

Open access

L. A. Dobrzański, W. Borek and J. Mazurkiewicz

Abstract

The purpose of the paper is to investigate X73MnSiAlNbTi25-1-3 high manganese austenitic steel containing 0.73% C to determine structural mechanisms decisive for increasing a reserve of cold deformation energy of such steel. The influence of a strain rate on the structure of the investigated steels and on the structural mechanisms decisive for their properties was analysed. Specialist research instrumentation was used for this purpose such as Scanning Transmission Microscopy (including EBSD examinations), conventional and high-resolution transmission electron microscopy together with diffraction examinations and metallographic examinations. It was found that the principal cause of an increased reserve of cold deformation energy of the investigated steels in dynamic conditions is the activation of mechanical twinning in the mutually intersecting systems in austenite grains and annealing twins, which are densifying when a cold deformation rate is growing, thereby confirming the basic mechanism of TWIP (TWinning Induced Plasticity).

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J. Lamut, J. Falkus, B. Jurjevec and M. Knap

Influence of Inclusions Modification on Nozzle Clogging

During the secondary refining of high strength steel in a ladle furnace aluminum is used for the melt deoxidation. Aluminates inclusions are modified with a calcium silicon injection in a melt. On the basis of the binary diagram CaO-Al203 solid and liquid calcium aluminates with different composition and shape are formed after calcium treatment. During the calcium silicon injection manganese sulphide is also modified and CaS or (Ca, Mn)S is formed and wrapped around calcium aluminates.

Because of rising of calcium bubbles during the calcium silicon injection a powerful melt stirring occurs. This enables inclusion coagulation and a reaction with a slag. Additionally, the MgO·Al203 spinels are formed.

Clogging of a tundish nozzle may occur during continuous casting of steel billets. Scull which forms on the nozzle's inner wall consists of spinel, calcium aluminates with various composition and calcium manganese sulphide.

Open access

A. Guzik, E. Talik, A. Pajączkowska, S. Turczyński and J. Kusz

Abstract

Monocrystalline fibres of undoped PrAlO3 and PrAlO3:0.1 Mn, have been grown by the pulling-down method under nitrogen atmosphere. The as-grown crystal doped with Mn had a visible brown core surrounded by a green ring, whereas this effect was weaker for the undoped PrAlO3. A coloration of the brown core was caused by a presence of Pr4+ ions. The presence of the Pr4+ ions was confirmed by XPS and magnetic studies. The XPS chemical analysis showed the increased concentration of oxygen in the crystals with the brown core. The most probable valency of manganese is Mn4+. It is located in Al3+ sites.

Open access

Tomasz Kleiber, Włodzimierz Krzesiński, Katarzyna Przygocka-Cyna and Tomasz Spiżewski

References [1] Dietary references intakes for vitamin A, vitamin K, arsenic, boron, chromium, copper, iodine, iron, manganese, molybdenum, nickel, silicon, vanadium and zinc. Website (December 2017) www.nap.edu/books/0309072794/html . [2] Dobson AW, Erikson KM, Aschner M. Manganese neurotoxicity. Ann NY Acad Sci. 2004;1012:115-128. http://libres.uncg.edu/ir/uncg/f/K_Erikson_ManganeseNeurotoxicity_2004.pdf . [3] Socha AL, Guerinot ML. Mn-euvering manganese: the role of transporter gene family members in manganese uptake and mobilization in

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Katya I. Milenova, Penko M. Nikolov, Nikoleta A. Kasabova and Ivalina A. Avramova

). Definition of polycrystalline ZnO catalytic sites and their role in CO hydrogenation. Appl. Catal. 25(1-2), 59-68. DOI: 10.1016/S0166-9834(00)81222-1. 9. Rekha, K., Nirmala, M., Nair, M. & Anukaliani, A. (2010). Structural, optical, photocatalytic and antibacterial activity of zinc oxide and manganese doped zinc oxide nanoparticles. Physica B, 405, 3180-3185. DOI: 10.1016/j.physb.2010.04.042. 10. Bellini, J., Morelli, M. & Kiminami, R. (2002). Electrical properties of polycrystalline ZnO: Cu obtained from freeze- -dried ZnO + copper (II

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Joanna Jordanowska and Monika Jakubus

Abstract

The article presents the work of the Water Treatment Plant in the town of Otoczna, located in the Wielkopolska province, before and after the modernization of the technological line. It includes the quality characteristics of the raw water and treated water with particular emphasis on changes in the quality indicators in the period 2002 -2012 in relation to the physicochemical parameters: the content of total iron and total manganese, the ammonium ion as well as organoleptic parameters(colour and turbidity). The efficiency of technological processes was analysed, including the processes of bed start up with chalcedonic sand to remove total iron and manganese and ammonium ion. Based on the survey, it was found that the applied modernization helped solve the problem of water quality, especially the removal of excessive concentrations of iron, manganese and ammonium nitrogen from groundwater.

It has been shown that one year after modernization of the technological line there was a high reduction degree of most parameters, respectively for the general iron content -99%, general manganese - 93% ammonia - 93%, turbidity - 94%. It has been proved, that chalcedonic turned out to be better filter material than quartz sand previously used till 2008. The studies have confirmed that the stage of modernization was soon followed by bed start-up for removing general iron from the groundwater. The stage of manganese removal required more time, about eight months for bed start-up. Furthermore, the technological modernization contributed to the improvement of the efficiency of the nitrification process.

Open access

Piotr Decyk, Andrzej B. Więckowski, Lidia Najder-Kozdrowska and Iveta Bilkova

References 1. Fierro, G., Morpurgo, S., Lo Jacono, M., Inversi, M., & Pettiti, I. (1998). Preparation, characterisation and catalytic activity of Cu-Zn-based manganites obtained from carbonate precursors. Appl. Catal. A-Gen ., 166 (2), 407–417. DOI: 10.1016/S0926-860X(97)00283-4. 2. Fei, J. H., Yang, M. X., Hou, Z. Y., & Zheng, X. M. (2004). Effect of the addition of manganese and zinc on the properties of copper-based catalyst for the synthesis of syngas to dimethyl ether. Energy Fuels , 18 (5), 1584–1587. DOI: 10.1021/ef049961f. 3. Fei, J

Open access

T. Pieczonka, M. Sułowski and A. Ciaś

References [1] S.C. Mitchell, A.S. Wronski, A. Cias, M. Stoytchev, Proc. PM 2 TEC’99, MPIF, Princeton, New Jersey 2 , Part 7 - P/M steels, 129 (1999). [2] A.S Wronski, B.S. Becker, C.S. Wright, S.C. Mitchell, Proc. DFPM’99, ed. L. Parilak and H. Danninger 1 , 155 (1999). [3] S.C. Mitchell, The Development of Powder Met­allurgy Manganese Containing Low-Alloy Steels (Ph.D. thesis, University of Bradford, Bradford, 2000, in Eng­lish). [4] A.S. Wronski, A. Cias, P. Barczy, M. Stoytchev et

Open access

Shiping Bai, Gu Jin, Delong Li, Xuemei Ding, Jianping Wang, Keying Zhang, Qiufeng Zeng, Fengjie Ji and Junmei Zhao

-160. Ao T., Pierce I.L., Power R., Pescatore A.J., Cantor A.H., Dawson K.A., Ford M.J. (2009). Effects of feeding different forms of zinc and copper on the performance and tissue mineral content of chicks. Poultry Sci., 88: 2171-2175. Bao Y.M., Choct M., Iji P.A., Bruerton K. (2007). Effect of organically complexed copper, iron, manganese, and zinc on broiler performance, mineral excretion, and accumulation in tissues. J. Appl. Poultry Res., 16: 448-455. Baumgartner S., Brown D.J., Salevsky E., Leach R.M. (1978). Copper deficiency in the