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331.
Ramaswamy Murugavel Ramasamy Pothiraja Namrata Singh 《Journal of organometallic chemistry》2007,692(10):1920-1923
Diorganotin dichloride-phosphonic diamide complex, [Ph2SnCl2(tBuP(O)(NHiPr)2)2] (1), is prepared by the addition of two equivalents of tBuP(O)(NHiPr)2 to one equivalents of Ph2SnCl2 either in the presence or absence of triethylamine. Compound 1 is a rare example of an all-trans SnA2B2C2 complex that contains H-bonded six-membered rings which are made up of six different main group elements. 相似文献
332.
Rainbow Connection Number and Radius 总被引:1,自引:0,他引:1
Manu Basavaraju L. Sunil Chandran Deepak Rajendraprasad Arunselvan Ramaswamy 《Graphs and Combinatorics》2014,30(2):275-285
The rainbow connection number, rc(G), of a connected graph G is the minimum number of colours needed to colour its edges, so that every pair of its vertices is connected by at least one path in which no two edges are coloured the same. In this note we show that for every bridgeless graph G with radius r, rc(G) ≤ r(r + 2). We demonstrate that this bound is the best possible for rc(G) as a function of r, not just for bridgeless graphs, but also for graphs of any stronger connectivity. It may be noted that for a general 1-connected graph G, rc(G) can be arbitrarily larger than its radius (K 1,n for instance). We further show that for every bridgeless graph G with radius r and chordality (size of a largest induced cycle) k, rc(G) ≤ rk. Hitherto, the only reported upper bound on the rainbow connection number of bridgeless graphs is 4n/5 ? 1, where n is order of the graph (Caro et al. in Electron J Comb 15(1):Research paper 57, 13, 2008). It is known that computing rc(G) is NP-Hard (Chakraborty and fischer in J Comb Optim 1–18, 2009). Here, we present a (r + 3)-factor approximation algorithm which runs in O(nm) time and a (d + 3)-factor approximation algorithm which runs in O(dm) time to rainbow colour any connected graph G on n vertices, with m edges, diameter d and radius r. 相似文献
333.
334.
Elham Azarpazhooh Parvin Sharayei Xin Rui Mehranoosh Gharibi-Tehrani Hosahalli S. Ramaswamy 《Molecules (Basel, Switzerland)》2022,27(23)
For the food sector, onion rejects are an appealing source of value-added byproducts. Bioactive compounds were recovered from yellow onion rejects using a pulse electric field process at 6000 v and 60 pulses. The onion extract was encapsulated with whey protein isolate (WPI), pectin (P), and sodium caseinate (SC) with a mass ratio of 1:5 (extract/wall material, w/w). A Simplex lattice with augmented axial points in the mixture design was applied for the optimization of wall material for the encapsulation of onion reject extract by freeze-drying (FD). The optimal wall materials were 47.6 g/100 g (SC), 10.0 g/100 g (P), and 42.4 g/100 g (WPI), with encapsulation yield (EY) of 85.1%, total phenolic content (TPC) of 48.7 mg gallic acid equivalent/g DW, total flavonoid content (TFC) of 92.0 mg quercetin equivalent/g DW, and DPPH capacity of 76.1%, respectively. The morphological properties of the optimal encapsulate demonstrated spherical particles with a rough surface. At optimal conditions, the minimum inhibitory concentration (MIC) of the extract (mean diameter of inhibition zone: 18.8 mm) was shown as antifungal activity against Aspergillus niger. 相似文献
335.
Dr. Tulasi Prapakaran Dr. C. I. Sathish Prof. Jiabao Yi Prof. Ajayan Vinu Prof. Ramaswamy Murugavel 《欧洲无机化学杂志》2023,26(17):e202300071
Starting from sterically encumbered 2,6-di-tert-butylphenyl phosphate (dtbppH2) and co-ligand 3,5-dimethyl pyrazole (dmpz), it is possible to isolate either mono-, di- or tetranuclear copper phosphates by varying the copper source and making attendant changes in the reaction conditions. For example, reaction of copper nitrate with dtbppH2 and dmpz at 60 °C leads to the isolation of the mononuclear copper phosphate [Cu(dtbppH)2(dmpz)(MeOH)2] ( 1 ) as the only product. However, the use of copper acetate in place of copper nitrate and conducting the reaction at the room temperature leads to the formation of both dinuclear [Cu(dtbpp)(dmpz)2]2 ( 2 ) and tetranuclear [Cu2(dtbpp)(dmpz)2(OAc)(MeO)]2 ( 3 ) from the same reaction mixture. Compounds 2 and 3 could be isolated in pure form through fractional crystallization. Copper phosphates 1 – 3 have been characterized by both analytical and spectroscopic methods including EPR and magnetic measurements. The molecular structures of all three compounds were established through single crystal diffraction studies. Dc magnetic measurements indicate antiferromagnetic interactions between the metal centres in all the compounds. 相似文献
336.