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Synteza i reaktywność kwasów boranatofosfinawych

Stankevič M., Pietrusiewicz M.

Wiadomości Chemiczne

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2006

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[Z] 60, 5-6

323-343

EN

Borane complexes of trivalent phosphorus compounds are versatile synthetic intermediates which are especially useful in the elaboration of phosphine structures and in the preparation of chiral phosphine ligands. Despite the synthetic importance and wide use of derivatives of phosphinous acid-boranes such as their esters (phosphinite-boranes), or acid chlorides (.sec-chlorophosphine-boranes), the parent phosphinous acid-boranes have until very recently remained practically unexplored. New developments of convenient and general methods of synthesis of phosphinous acid-boranes from secondary phosphine oxides or from phosphinic chlorides have made them now readily accessible as a novel class of organophosphorus reagents. When nonsymmetrically substituted phosphinous acid-boranes bear a center of chirality at P and are configurationally stable. Phosphinous acid-boranes possess a rich reactivity pattern offering many useful synthetic transformations through the reactions at their R, O, or B, reactivity centers. A large variety of other organophosphorus compounds such as phosphinite-boranes, boranatophosphinous anhydrides and mixed anhydrides, secondary phosphine-boranes, tertiary phosphine-boranes, secondary phosphine oxides, phosphinic halides, and oxaphosphaborolidines, can all be readily derived from phosphinous acid-boranes in a single synthetic operation.

2

Extinguish of vibrations on a plate under acting of two point forces

Awrejcewicz J, Pietrusiewicz M., Lamarque C.-H.

Vibrations in Physical Systems

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2002

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Vol. 20

96--97

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Wykorzystanie dodatkowej masy punktowej do aktywnego sterowania poziomem drgań belki

Awrejcewicz J., Wodzicki W., Pietrusiewicz M.

Prace Naukowe Instytutu Konstrukcji i Eksploatacji Maszyn Politechniki Wrocławskiej. Konferencje

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2002

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Vol. 85, nr 25

61-66

PL

W pracy przedstawiono ideę aktywnego sterowania drganiami cienkiej belki obciążonej siłą punktową. Strategię sterowania oparto na modyfikacji strukturalnej belki w postaci dołączenia masy punktowej o stałej wartości. W celu określenia właściwych położeń masy skorzystano z pojęcia receptancji oraz elementów liniowej teorii belek cienkich. Przedstawiono pewne wyniki dla belki swobodnie podpartej.

EN

In this paper an idea of active vibration control of a beam being under action of point harmonic force is presented. The control strategy consists in a structural modification of the beam by constant weight concentrated mass. In order to obtain the right locations of the added mass a receptance technique and linear theory of beams are used. Some results of the application of this idea are also presented.