Reflection of shock-wave in pur foam from rigid wall

Keller proposed that a building, a mechanical installation or a body wrapped bya layer of foam plastics may be an efficient means for protection from damage ofblast wave. However, the practical effect was beyond expectation. For example, agunner wearing the foam plastics-padded waistcoat was injured more seriously by theblast wave from a muzzle. Monti took the foam plastics as homogeneous two-phasemedium and analyzed it with the theory of dusty flow. The obtained results showthat the peak pressure behind the reflected shock wave from rigid wall with foamcoat exceeds obviously that without foam coat under the same condition. Gel'fand,Patz and Weaver made experimental observations by means of shock tubes and veri-

Le pur et l’impur: (sur deux questions d’histoire de la philosophie dans L’Etre et l’événement)

Paris

Bis(trifluoromethyl)mercury(II) complexes with purine and 3,5-dimethyl-4 '-amino-triazole as ligands, [Hg(CF3)(2)(Pur)](4) and [Hg(CF3)(2)(Dat)](2)

Colourless single crystals of [Hg(CF3)(2)(Pur)](4) and [Hg(CF3)(2)(Dat)](2) were obtained from aqueous and etheric solutions of the respective components Purine, (imidazo[4,5-d]pyrimidine, Pur), 3,5-dimethyl-4 '-amino-triazole (Dat) and bis(trifluoromethyl)mercury(II), Hg(CF3)(2). [Hg(CF3)(2)(Pur)](4) crystallizes with the tetragonal system (P-4, Z = 8, a = 1486.8(2), c = 1026.2(l) pm, R-all = 0.0657) with tetrameric molecules consisting of four purine molecules bridged by slightly bent Hg(CF3)2 molecules forming a cage with the CF3 ligands surrounding this cage. The two modifications of [Hg(Dat)(CF3)2]2 (1: 170 K, triclinic, P-1, Z = 2, a 814.9(2), b = 845.4(2), c = 968.4(3) pm, alpha = 106.55(2)degrees, beta= 103.41(2)degrees, gamma = 110.79(2)degrees, R-all = 0.1189; II: monoclinic, P2(1)/c, Z = 8, a = 879.8(2), b = 1731.0(3), c = 1593.9(3) pm, beta = 106.89(2)degrees, R-all = 0.1199) both contain dimeric molecules that are stacked parallel to one crystal axis to strands which are arranged in a parallel fashion in I and rotated against each other in 11 by 110 degrees. In both, the tetrameric [Hg(CF3)(2)(Pur)](4) and the dimeric [Hg(CF3)(2)(Dat)](2) the Hg(CF3)(2) molecules are slightly bent (around 167 and 170 degrees) and rather weakly attached to the N-donor ligands Pur and Dat with Hg-N distances around 272 pm, although in both cases the Hg atoms bridge between two ligand molecules.

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1857 (T3)-1860.

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1851 (T2)-1856.

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1863 (T5)-1864.

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1861 (T4)-1862.

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1851 (T1).

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1872 (T14)-1874.

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1875 (T5)-1877.

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1869 (T3)-1871.

Stud-book français. Registre des chevaux de pur sang nés ou importés en France

1884 (T8)-1886.

L'Īśvaragītā : le chant de Śiva, texte extrait du Kūrma-Purāṇa / trad. du sanskrit par P.-E. Dumont,..

[Purāṇa. Kūrma-Purāṇa (sanskrit-français). Extrait. 1933]