980 resultados para HD8053 .A25 1902
Resumo:
The following synonymies are proposed based on examination of primary types (lectotypes are designated for all taxa except those marked with a '*'): Lemidia spinnipennis Lea, 1907 syn. n. and Lemidia bicolor Schenkling, 1906 syn. n. = Lemidia biaculeata (Westwood); Lemidia mastersi Lea, 1907 syn. n. = Lemidia circumcincta Schenkling, 1906; Lemidia albonotata Pic, 1941 syn. n. = Lemidia laticeps Lea, 1907; Lemidia australiae Lea, 1907 syn. n. = Lemidia maculata Schenkling, 1902; Lemidia bilineatra Lea, 1907 syn. n. = Lemidia maculicollis Gorham, 1877; Lemidia decolor Pic, 1941 syn. n. = Lemidia munda Blackburn, 1892; *Phlogistus conspiciendus Elston, 1926 syn. n. = Mimolesterus ventralis (Westwood); Thanasimus cursorius Westwood, 1853 syn. n. and Stigmatium dispar Kuwert, 1894 syn. n. = Stigmatium acerbum (Newman); Stigmatium fasciatoventre Chevrolat, 1874 syn. n., Stigmatium flavescens Chevrolat, 1874 syn. n. and *Xestonotus eximius Kuwert, 1894 syn. n. = Stigmatium laevium Macleay, 1872; Stigmatium versipelle Gorham, 1876 syn. n. and Xestonotus (Cyclotomocerus) australicus Kuwert, 1894 syn. n. = Stigmatium varipes Chevrolat, 1876; Tarsostenus pulcher Macleay, 1872 syn. n. = *Tarsostenus carus (Newman, 1840). The available name Tarsosternus pulcher Macleay, 1872 is deemed a lapsus calami and emended to Tarsostenus pulcher Macleay, 1872.
Resumo:
Diphenyl sulphoxide (DPSO) complexes of TiO2+, ZrO2+, VO2+ and UO22+ have been prepared and characterized by physicochemical methods. The complexes have the formulae: [TiO(DPSO)5]2 (ClO4)4, [ZrO(DPSO)6] (ClO4)2, [VO(DPSO)5](ClO4)2, [VO(DPSO)3Cl2], [UO2-(DPSO)4] (ClO4)2, [UO2(DPSO)2Cl2],[UO2(DPSO)2(NO3)2]and[UO2(DPSO)2(CH3COO)2]. The i.r. spectra show the coordination through the oxygen of the sulphoxide in all the complexes. The spectroscopic, conductivity and crysoscopic studies indicate the ionic nature of the perchlorate, while the chloride, nitrate and acetate are coordinated, the last two being bidentate. The probable stereochemistry of the complexes is discussed. The complexes decompose exothermally.
Resumo:
The doctoral dissertation Critic Einari J. Vehmas and Modern Art deals with one of the central figures of the Finnish art scene and his work as an art critic, art museum curator and cultural critic. The main body of research material consists of the writings of Einari J. Vehmas (1902 1980) from 1937 to the late 1960s. Vehmas wrote art reviews for magazines, and from the year 1945 he was a regular art critic for one of the major newspapers in Finland. Vehmas was heavily inclined towards French literature and visual arts. Marcel Proust and Charles Baudelaire influenced his views on the nature of art from the late 1920s onwards. Vehmas is commonly regarded as the most influential art critic of post-war Finland. His writings have been referred to and cited in numerous research papers on Finnish 20th-century art. A lesser known aspect of his work is his position as the deputy director of the Ateneum Art Museum, the Finnish national gallery. Through his art museum work, his opinions also shaped the canon of modern art considered particularly Finnish following the second world war. The main emphasis of the dissertation is on studying Vehmas s writings, but it also illustrates the diversity of his involvement in Finnish cultural life through biographical documents. The long chronological span of the dissertation emphasises how certain central themes accumulate in Vehmas s writings. The aim of the dissertation is also to show how strongly certain philosophical and theoretical concepts from the early 20th century, specifically Wassily Kandinsky s principle of inner necessity and Henri Bergson s epistemology highlighting intuition and instinct, continued to influence the Finnish art discourse even in the early 1960s, in part thanks to the writings of Vehmas. Throughout his production, Vehmas contemplated the state and future of modern art and humanity. Vehmas used a colourful, vitalistic rhetoric to emphasise the role of modern art as a building block of culture and humanity. At the same time, however, he was a cultural pessimist whose art views became infused with anxiety, a sense of loss, and a desire to turn his back on the world.
Resumo:
Dimethyl sulphoxide (DMSO) and dimethyl formamide (DMF) complexes of Mn(III) perchlorate have been prepared and their conductivity, magnetic susceptibility and i.r. and electronic spectra studied. The complexes behave as uni-trivalent electrolytes in acetonitrile. Their magnetic moments of 5·1 B.M. show them to be of high spin type. Infra-red spectra show that oxygen is the donor atom in both complexes. The spin allowed electronic transition for d4 system, around 20,000 cm−1, ascribable to the 5Eg → 5T2g transition, suggests an octahedral configuration for these complexes
Resumo:
A ligand series obtained from V = O stretching frequencies for different monomeric complexes of oxovanadium(IV) is shown to parallel the nephelauxetic series. The ligand series obtained from streching frequencies of other systems are also shown to compare well with the nephelauxetic series rather than the spectrochemical series.
Resumo:
Dimethyl sulphoxide complexes of lanthanide and yttrium nitrates of the general formula M(DMSO)n(NO3)3 where M = La, Ce, Pr, Nd, Sm or Gd; n = 4 and M = Y, Ho or Yb; n = 3 have been isolated and characterized. The i.r. data besides excluding the presence of D3h nitrate, reveal co-ordination through the oxygen atom of the dimethyl sulphoxide. The complexes are monomeric in acetonitrile. Molecular conductance data in acetone, acetonitrile, dimethyl formamide and dimethyl sulphoxide suggest a co-ordination number of eight for the lighter lanthanides and seven for yttrium and the heavier lanthanides.
Resumo:
Dimethylsulphoxide (DMSO) complexes of rare-earth perchlorates of the formula M(ClO4)3·n DMSO (M = La, Ce, Pr and Nd, n = 8; M = Sm, Gd and Y, n = 7) have been prepared. I.r. studies indicate co-ordination through oxygen. Cryoscopic and conductivity data show co-ordination number of 7 and 8.
Resumo:
The solvolytic disproportionation of non-stoichiometric PrOχ and TbOχ in acid solutions to produce higher oxides has been investigated. Some new non-stoichiometric phases have been reported. A number of interesting features of the non-stoichiometric rare earth oxides have been discussed and the need for a satisfactory structural model has been pointed out.
Resumo:
Oxalato oxovanadium (IV) complexes with neutral ligand molecules like dimethyl sulphoxide (DMSO) and antipyrine (Apy), VOOX·2DMSO and VOOX·2Apy and complex oxalates of oxovanadium (IV)-(NH4)2[VOOX2]·2H2O, (NH4)2[(VO)2OX3]·6H2O and (NH4)2[(VO)2OX3] have been prepared and characterized by different methods. In the divanadyl complexes, V-V and V-O-V-O types of bonding are shown to be absent by magnetic and spectral data and a bridged oxalato group co-ordinated to the two vanadium atoms is shown to be present, in addition to the usual bidentate oxalate groups. The possible stereochemical arrangements are indicated for the complexes.
Resumo:
The interaction of iodine with triphenylamine ,tripheny lphosphine, triphenylarsine and triphenystibine has been investigated by electronic spectroscopy. Transformation of the outer charge-transfer complexes to the inner complexes (quarternary salts) has been examined. The relations of the ionization potentials of the donors with the hvc.t have been discussed and various c.t. parameters have been estimated. Hydrogen bonding of these donors with phenol have been reported.
Resumo:
Dimethyl formamide complexes of five rare-earth nitrates, M(DMF)4(NO3)3 where M = La, Pr, Nd, Sm or Y have been prepared and their infra-red spectra and conductivities in nitromethane and DMF studied. It is suggested that the co-ordination number of the metal ion in these complexes is nine.
Resumo:
The preparation of three different types of carbonates of praseodymium, neodymium and terbium has been described. The carbonates have been characterized by potentiometry, chemical analysis, X-ray crystallography, infra-red spectroscopy and by their thermal behaviour. The thermal decomposition of several carbonates has been studied exhaustively under a variety of conditions and the stoicheiometry, thermodynamics and energetics of the reactions at various stages of decomposition have been examined. The stoicheiometry of the oxides obtained as final products of decomposition has been examined.