18 research outputs found
8-(Diphenylphosphanyl)quinoline
The title compound, C21H16NP, is a known P—N chelator and various crystal structures of its metal complexes have been reported. However, no crystallographic evidence of the free ligand has been given to date. The phenyl rings are almost orthogonal to one another [dihedral angle = 88.9 (1)°], and they are twisted from the mean plane of the quinoline by 80.5 (1) and 76.3 (1)°
Bis(2,2′-bipyridine)(5-isothiocyanato-1,10-phenanthroline)ruthenium(II) bis(hexafluoridophosphate) acetonitrile solvate
The title compound, [Ru(C10H8N2)2(C13H7N3S)](PF6)2·CH3CN, was synthesized by the reaction of thiophosgene and bis(2,2′-bipyridine)(1,10-phenanthrolin-5-amine)ruthenium(II) bis(hexafluoridophosphate). The RuII atom adopts a slightly distorted octahedral RuN6 coordinaton formed by four N atoms of two bipyridine ligands and by two N atoms of the 1,10-phenantroline ligand. The isothiocyanate group is almost linear, with an N—C—S angle of 174.4 (6)°. Two of the three hexafluoridophosphate counter-anions are located on inversion centres
Determination of acid dissociation constants of some monobasic organic acids in acetonitrile from molar conductance
1263-1265The pKa values of some 14 monobasic organic acids like carboxylates, phenols, etc. are determined in acetonitrile from conductivity measurements. These pKa values are found to be higher than those reported in the aqueous medium on the average by 2.8 (± 1.1) pKa unit. A thermodynamic rationalisation of this observation is provided. It emerges that an acid should be more acidic in water than in acetonitrile as water being more polar than acetonitrile brings about greater ionisation of an acid
A new emissive Ru(II)N₅O core
764-767From the reaction of cis-Ru(1,10-phenanthroline)₂Cl₂.2H₂O with 2-picolinic acid in 1:1 molar ratio in degassed methanol-water mixture, [Ru(1,10-phenanthroline)₂(2-picolinate)]PF₆.H₂O (1) has been isolated as a red compound by adding excess of NH₄PF₆. Single crystal X-ray crystallography shows that the metal in 1 has an octahedral N₅O coordination sphere. Complex 1 displays ¹MLCT bands in the 400-500 nm region in acetonitrile. Upon excitation at 435 nm, complex 1 gives rise to a broad emis-sion band at 675 nm in acetonitrile at room temperature with a quantum yield of 0.0022. The energy of the MLCT state in 1 is estimated as 1.99 eV. Since, from cyclic voltammetry, the ground state potential of the Ru(II/III) couple in 1 is found to be 1.01 V vs NHE, the potential of the same couple in the excited state is calcu-lated as -0.98 V vs NHE. The emissive state in 1 seems to be the triplet Ru(II) → 1,10-phenanthroline charge transfer state
Neutral Re (I) complexes for anion sensing
Anion sensing properties toward F− , OAc− and H2PO4 − were studied for new mononuclear and dinuclear Re(I) complexes based on a five-substituted phenanthroline moiety bearing a thiourea hydrogen-bonding receptor. Log(K 1:1) values between 4 and 6 were obtained for the complexes by UV–vis titrations and between 3 and 5 by 1H NMR titrations. The effect of hydrogen-bonding versus deprotonation of the thiourea receptor upon addition of the anions was also evaluated by UV–vis and NMR titration techniques. In addition, an X-ray structure of the Re(I) precursor complex is reported and the chirality of the mononuclear and dinuclear complexes is discussed
Synthesis and photophysical properties of C3-symmetric tris(pyridyl)truxene scaffolds of Ru(II) and Re(I)
Facial Ru(II)- and Re(I)-complexes of a novel face-capping tris(pyridyl)truxene ligand were synthesised and characterised by various analytical techniques including single crystal XRD. The Ru(II) complex exhibits unusual green phosphorescence with a long excited-state lifetime
High Productivity and High Pci Operation at ‘H’ Blast Furnace, Tata Steel – The Operating Experiences with Indian Raw Materials
Scarcity of metallurgical grade coal or coke is known to all the iron making units since long. Various attempts have been made to optimize the requirement of coal by developing alternative route for iron making, alternative methods to meet the thermal requirement of the blast furnace iron making process. Most popular amongst these developments has been the development of injection of low quality coal in the blast furnaces at the tuyere level. In order to optimize cost and improve productivity,Tata Steel has been practicing injection of coal in the blast furnaces at its Jamshedpur works since 1991. Under the growth plan, ‘H’blast furnace (capacity 2.5 MT) has been commissioned on 31st May’2008. It had achieved an average monthly productivity of 2.77T/Day/m3 and maximum daily productivity of 3.17 T/m3 (working volume) with average coal injection rate 150Kg/thm under Indian raw material conditions. This paper covers the operation experiences and technical considerations employed in H Blast Furnace to achieve the above performances