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Letter from A.L. Monmerqué de Courmont.
No full textLetter from A.L. Monmerqué de Courmont, possibly Adélaïde Louise de Monmerqué (1767-1835) who had been married to Louis Marie Le Bas de Courmont (1741-1794), dated 10 pluvoise. It is not addressed but was presumably sent to Philippe-Antoine Merlin, as it comprises the verso of one of his requisitions from 1802. In this letter the author requests a day and an hour when she (or he) might meet with the recipient
Lack of efficacy of troglitazone at clinically achievable concentrations, with or without 9-cis retinoic acid or cytotoxic agents, for hepatocellular carcinoma cell lines
No full textAlthough the PPARg agonist troglitazone has been shown to induce growth inhibition of hepatocellular carcinoma (HCC) cells at high
concentration, this study indicates troglitazone does not significantly inhibit the growth of HCC cells at clinically achievable
concentrations (1–10 mM), and this lack of activity could not be improved by the addition of 9-cis-retinoic acid. Furthermore, no
synergistic effect was found between troglitazone and cytotoxic anticancer agents
Preparation, characterization, and structural systematics of diphosphane and diarsane complexes of gallium(III) halides
No full textThe diphosphane o-C6H4(PMe2)2 reacts with GaX3 (X = Cl, Br, or I) in a 1:1 molar ratio in dry toluene to give trans-[GaX2{o-C6H4(PMe2)2}2][GaX4], the cations of which contain the first examples of six-coordinate gallium in a phosphane complex. The use of a 1:2 ligand/GaCl3 ratio produced [GaCl2{o-C6H4(PMe2)2}][GaCl4], containing a pseudotetrahedral cation, and similar pseudotetrahedral [GaX2{o-C6H4(PPh2)2}][GaX4] complexes are the only products isolated with the bulkier o-C6H4(PPh2)2. On the other hand, Et2P(CH2)2PEt2, which has a flexible aliphatic backbone, formed [(X3Ga)2{-Et2P(CH2)2PEt2}], in which the ligand bridges two pseudotetrahedral gallium centers. The diarsane, o-C6H4(AsMe2)2, formed [GaX2{o-C6H4(AsMe2)2}][GaX4], also containing pseudotetrahedral cations, and in marked contrast to the diphosphane analogue, no six-coordinate complexes form; a very rare example where these two much studied ligands behave differently towards a common metal acceptor. The complexes [(I3Ga)2{-Ph2As(CH2)2AsPh2}] and [GaX3(AsMe3)] are also described. The X-ray structures of trans-[GaX2{o-C6H4(PMe2)2}2][GaX4] (X = Cl, Br or I), [GaCl2{o-C6H4(PPh2)2}][GaCl4], [GaX2{o-C6H4(AsMe2)2}][GaX4] (X = Cl or I), [(I3Ga)2{-Ph2As(CH2)2AsPh2}], and [GaX3(AsMe3)] (X = Cl, Br or I) are reported, and the structural trends are discussed. The solution behavior of the complexes has been explored using a combination of 31P{1H} and 71Ga NMR spectroscopy
Gallium(III) halide complexes with phosphines, arsines and phosphine oxides - a comparative study
No full textThe phosphine oxide complexes [GaX3(Me3PO)] and [(GaX3)2{?-o-C6H4(CH2P(O)Ph2)2}] have been prepared and characterised by microanalysis, IR and multinuclear NMR (1H, 13C{1H}, 31P{1H} and 71Ga) spectroscopy. The structures of [GaCl3(Me3PO)], [(GaBr3)2{?-o-C6H4(CH2P(O)Ph2)2}] and of the ionic product [GaI2(Me3PO)2][GaI4] have been determined and show that the Lewis acidity of the gallium halides towards phosphinoyl ligands diminishes as the halogen becomes heavier. The [GaX3(Ph3E)] (X = Cl, Br or I; E = P or As) and [(GaX3)2{?-o-C6H4(CH2PPh2)2}] (X = Br or I) have been prepared and their structural and spectroscopic properties compared with those of the phosphinoyl complexes. The results, and competitive solution NMR studies, show that Ga(III) binds the hard R3PO in preference to the softer phosphine or arsine ligands. Hydrolysis of gallium(III) phosphines is shown to lead to [R3PH][GaX4], but in contrast to some other p-block halides, GaX3 do not promote air-oxidation of R3P to R3PO.<br/
Synthesis, spectroscopic and structural systematics of complexes of germanium(IV) halides (GeX4, X = F, Cl, Br or I) with phosphane oxides and related oxygen donor ligands
No full textThe first series of phosphane oxide complexes of germanium(IV) halides have been prepared, including trans-[GeF4(R3PO)2] (R = Me, Et or Ph), trans-[GeCl4(Et3PO)2], fac-[GeCl3(Me3PO)3]2[GeCl6] and cis-[GeX2(Me3PO)4]X2 (X = Cl or Br) and characterised by IR and multinuclear NMR (1H, 19F{1H} and 31P{1H}) spectroscopy. Crystal structures of all the above (except trans-[GeCl4(Et3PO)2]) are described. Remarkably, under mild conditions Me3PO displaces halide ligands from GeX4 (X = Cl, Br) to form the cationic species above. Ph3AsO forms trans-[GeF4(Ph3AsO)2], but reaction of Ph3AsO or Me3AsO with GeCl4 leads to the corresponding R3AsCl2. The complexes [GeF4(MeCN)2], [GeF4(thf)2] and [GeF4(MeOCH2CH2OMe)] are also described and the relative Lewis acidities of GeX4 established
mu-1,2-Bis(diphenylphosphino)ethane-kappa P-2 : P-bis[trichloridogallium(III)]
No full textThe centrosymmetric molecule of the title compound, [(GaCl3)2(C26H24P2)] or [(GaCl3)2{[mu]-Ph2P(CH2)2PPh2}], consists of two pseudo-tetrahedral Ga centres coordinated by three Cl atoms [Ga-Cl = 2.1608 (8)-2.1648 (8) Å] and bridged by the diphosphane ligand [Ga-P = 2.3854 (8) Å]
S.L.I.M., a small linear interdependent model of eight EU-member states, the USA and Japan
Full text linkInternational Economics;EU
A Review of Some Updates in the 13th Edition of “Sears and Zemansky’s University Physics with Modern Physics” (Authors: Hugh D. Young and Roger A. Freedman; contributing author, A. Lewis Ford; 2012)
Full text linkYoung, H.D.; and Freedman, R.A.; Ford, A.L. (contributing author). 2012. Sears and Zemansky’s University Physics with Modern Physics. 13th ed.Pearson Education, Inc., Addison-Wesley, San Francisco, CA, USA
Absorption refrigeration machines: Theoretical and experimental assessment of the performance of aqua-ammonia absorption machines operated at marginal conditions, e.g. when powered by solar or waste heat. Development of a new type of absorber.
No full textMechanical, Maritime and Materials EngineeringMechanical, Maritime and Materials Engineerin
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