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1

Friction Stir Welding of Dissimilar Butt Joints with Novel Joint Geometry

100%

Jayabalakrishnan D., Balasubramanian M.

Acta Physica Polonica A

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2018

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vol. 133

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issue 1

94-100

EN

In this study, 1 mm thin sheets of AA 6061 and steel were welded by friction stir, with new joint geometry. Conventional friction stir welding develops high distortion to the specimen, particularly when the thickness is very small. In this process, friction stir welding is carried out by a tool without probe and with new joint geometry. Contrary to the conventional friction stir welding, where various tool profiles are used to obtain successful joints, the present study of investigation focused on developing a profile in the sheet metal edges to be joined. The aluminium sheet was positioned on the contoured steel sheet. Rotating tool with tilt angle was made to progress into the top sheet. Frictional heat plasticized the upper blank and the edges of the aluminium sheet were forged and extruded into the steel contour. The welding between steel and aluminium was due to a coalescence of the two materials and clamping effect was provided by the contour in the steel sheet. Tensile test was conducted to evaluate the quality of the welding along with macro and micro metallographic investigations. Further to this, scanning electron microscopy with energy dispersive X-ray and X-ray diffraction analysis have been done to understand the presence of intermetallics at the weld nugget. Tensile strength of 122.22 MPa was achieved. Intermetallics of Mg₂Si, MnAl₆ and FeAl₆, Al₅Fe₂ was found as dominant compound at the interface. Welding of thin sheets is enhanced by form clamping and chemical diffusion bonding.

2

Effect of aluminium on plant growth and metabolism.

88%

Mossor-Pietraszewska T.

Acta Biochimica Polonica

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2001

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vol. 48

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issue 3

673-686

EN

Aluminium toxicity is one of the major factors that limit plant growth and development in many acid soils. Root cells plasma membrane, particularly of the root apex, seems to be a major target of Al toxicity. However, strong interaction of Al3+, the main Al toxic form, with oxygen donor ligands (proteins, nucleic acids, polysaccharides) results in the inhibition of cell division, cell extension, and transport. Although the identification of Al tolerance genes is under way, the mechanism of their expression remains obscure.Soil chemical factors that limit root growth in acid soils, diminish crop production, include Al, Mn and various cations, and also deficiency or unavailability of Ca, Mg, P, Mo, and Si. These effects are further complicated by interactions of Al with other ions in different plant genotypes and under stress conditions (Foy, 1992). Cytotoxicity of Al has been well documented in plants (Delhaize & Ryan, 1995; Horst et al., 1999; Kollmeier et al., 2000; Marienfeld et al., 2000). It is generally known that plants grown in acid soils due to Al solubility at low pH have reduced root systems and exhibit a variety of nutrient-deficiency symptoms, with a consequent decrease in yield. In many countries with naturally acid soils, which constitute about 40% of world arable soil (LeNoble et al., 1996), Al toxicity is a major agricultural problem, and is intensively studied in plant systems.The effects of aluminium on plant growth, crop yield, uptake and nutrients distribution in vegetative and reproductive parts are still not fully understood. This review discusses recent information on aluminium toxicity with an emphasis on plant response to Al stress.

3

Mechanical and wear behaviour of the Al-Mg-nano ZrC composite obtained by means of the powder metallurgy method

88%

Sankaranarayanan G., Balaji A. N., Velmanirajan K., Gangatharan K.

Bulletin of the Polish Academy of Sciences: Technical Sciences

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2018

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issue 5

4

Inhibitive tendency of zinc gluconate for aluminium alloy in sulphuric acid solution

75%

Sanni O., Loto C. A., Popoola A. P. I.

Polish Journal of Chemical Technology

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2013

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vol. 15

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issue 4

60-64

EN

The corrosion inhibition of aluminium alloy in 0.5M H2SO4 solution in the presence of zinc gluconate at 301 K was investigated using weight loss and an electrochemical method. Surface analysis of the aluminium alloy sample was reviewed by a high resolution scanning electron microscope equipped with energy dispersive spectroscopy (HRSEM/ EDS). The readings were taken after 48 h for 28 days while the concentration of the inhibitor was varied from 0.5 to 2.0% g/v with an interval of 0.5. The result of the investigation shows that zinc gluconate has a good corrosion inhibition effect for aluminium alloy in 0.5 molar sulphuric acid solution and its efficiency attains more than 67% at 1.5% g/v concentration of zinc gluconate at 301 K. The potentiodynamic polarization data showed that zinc gluconate acts as a mixed type corrosion inhibitor. The adsorption of zinc gluconate on aluminium alloy has been found to obey Freundlich adsorption isotherm at all the concentration of zinc gluconate studied. The results obtained from different methods are in good agreement.

5

Numerical Modelling of Metal Melt Refining Process in Ladle With Rotating Impeller and Breakwaters

75%

Sviželová J., Tkadlečková M., Michalek K., Walek J., Saternus M., Pieprzyca J., Merder T.

Archives of Metallurgy and Materials

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2019

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vol. 64

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issue 2

6

The Influence of Small Amounts of Aluminium on the Spheroidization of Cast Iron with Cerium Mischmetal

75%

Soiński M.

Archives of Foundry Engineering

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2012

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issue 2

7

Antimony Influence on Shape of Eutectic Silicium in Al-Si Based Alloys

75%

Bolibruchová D., Brůna M.

Archives of Foundry Engineering

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2017

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vol. 17

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issue 4

8

The content of toxic metals in different types of tea and their impact on consumers health

63%

Watrak S., Rajkowska-Myśliwiec M., Protasowicki M.

Kosmos

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2016

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vol. 65

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issue 4

563-571

EN

Tea is one of the most popular beverages in the world, which, along with a number of beneficial health ingredients, such as trace elements, also contains undesired substances - as impurities. Among the impurities occur heavy metals, and their presence in tea leaves can pose serious problems to human health because they are not biodegradable, remain in the environment and can become part of the food chain. The total metal content of the tea leaves and infusions depends on the type of tea (green, black) and on the influence of other factors, including the properties of the soil. Despite the limited extent of metal migration from the dried tea to infusions, tea pollution with metals such as lead, cadmium or mercury is not indifferent to human health.

PL

Herbata jest jednym z najbardziej popularnych napojów na świecie, który obok wielu korzystnych dla zdrowia składników, jak mikroelementy, zawiera również te niepożądane - stanowiące zanieczyszczenie. Wśród nich znajdują się metale ciężkie, których obecność w liściach herbaty może stwarzać poważne problemy dla zdrowia ludzkiego, ponieważ nie ulegają one biodegradacji, a pozostając w środowisku mogą stać się częścią łańcucha pokarmowego. Całkowita zawartość metali w liściach herbat oraz w naparach zależy od rodzaju herbaty (zielona, czarna) oraz od wpływu wielu innych czynników, w tym właściwości gleby. Pomimo ograniczonej migracji metali z suszu do naparów zanieczyszczenie herbat metalami tj. ołów, kadm czy rtęć nie jest obojętne dla zdrowia człowieka. REFERENCES

9

Interpolation formulas for coefficients reducing the strength of steel and aluminum alloys in increasing temperatures

39%

Gwóźdź M., Gwóźdź M.

Archives of Civil Engineering

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2017

|

issue 2

Refine search results

Friction Stir Welding of Dissimilar Butt Joints with Novel Joint Geometry

Effect of aluminium on plant growth and metabolism.

Mechanical and wear behaviour of the Al-Mg-nano ZrC composite obtained by means of the powder metallurgy method

Inhibitive tendency of zinc gluconate for aluminium alloy in sulphuric acid solution

Numerical Modelling of Metal Melt Refining Process in Ladle With Rotating Impeller and Breakwaters

The Influence of Small Amounts of Aluminium on the Spheroidization of Cast Iron with Cerium Mischmetal

Antimony Influence on Shape of Eutectic Silicium in Al-Si Based Alloys

The content of toxic metals in different types of tea and their impact on consumers health

Interpolation formulas for coefficients reducing the strength of steel and aluminum alloys in increasing temperatures