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Assessment of surface roughness in MQL assisted turning process of titanium alloy with application of TOPSIS-AHP method

Bartoszuk M., Gupta M. K.

Journal of Machine Engineering

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2018

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Vol. 18, No. 2

97--105

EN

The optimization of surface roughness values considered as one of the most significant issues regarding turning process of titanium alloys with the use of minimum quantity lubrication (MQL) method. With such an aim in mind, the application of TOPSIS-AHP method is implemented in order to establish the most favourable cutting parameters for the following values of surface roughness: Ra, Rq and Rz in machining of titanium alloys regarding MQL conditions. The proposed methodology consists of the two stages. At the beginning, tests on turning process were performed on CNC lathe, taking feed rate, approach angle, and cutting speed as input parameters. Then, the TOPSIS-AHP method was applied on the given experimental data and the optimum machining parameters were determined. The findings from current investigations showed that, lower values of cutting speed, feed rate and middle value of approach angle shows the optimal results.

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Synthesis and spectroscopic characterization of new tin(II) complexes containing nitrogen and oxygen donor ligands

Singh H. L., Gupta M. K., Varshney S., Varshney A. K.

Bulletin of the Polish Academy of Sciences. Chemistry

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2003

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Vol. 51, No. 1

5-14

EN

Some new tin(II) complexes have been synthesized by the reactions of tin(II) methoxide with nitrogen donor ligands. The ligands used in these studies are condensation products of heterocyclic aldehydes/ketones and sulpha drugs. Their structures have been confirmed on the basis of elemental analyses, ultraviolet, infrared and multinuclear magnetic resonance (1H, (13)C and (119)Sn) spectral studies. The bivalent nature and their square pyramidal geometry around tin(II) have been deduced on the basis of 119Sn Mossbauer spectral data. Monomeric and non-electrolytic nature of these complexes have been confirmed by molecular weight determinations and conductance measurements.

3

Synthesis and spectroscopic studies of tin(IV) complexes of biologically active Schiff bases of sulpha drugs and heterocyclic aldehydes/ketones

Gupta M. K., Singh H. L., Tripaathi U. D., Varshney A. K.

Bulletin of the Polish Academy of Sciences. Chemistry

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2000

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Vol. 48, No. 3

195-201

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Coordination behaviour of biologically active Shiff bases of amino acids towards stannous ion

Singh H. L., Sharma M., Gupta M. K., Varshney A. K.

Bulletin of the Polish Academy of Sciences. Chemistry

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1999

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Vol. 47, No. 2

103-110

EN

Reaction of tin (II) methoxide with Schiff bases derived by condensation of 2-hydroxy-1-naphthaldehyde, salicylaldehyde with glycine, b-alanine, a-valine, a-iso-leucine and a-tryptophan in 1:1 molar ratio gives a new series of tin(II) complexes. The complexes are monomeric and of non-electrolytic nature. The coordination behaviour of Schiff bases through phenolic and acidic oxygens and azomethine nitrogen towards tin atom has been investigated by infrared and multinuclear magnetic resonance (1 H, 130 and 119Sn) spectral studies. Schiff bases and their tin complexes have also been screened for their antifungal and antibacterial activities as several fungi and bacteria are found quite active in this respect.