Topography of wound canals and possibilities of collateral blood circulation

By complexed structural and functional study performed in 76 dogs in acute, subacute and chronic experiments, destruction of muscles of the extremity, intraorganic vascular bed of which does not participate in collateral blood circulation was shown not to be an impairing factor in vascular trauma. If the wound canal localization directly relates to the topography of most important collaterals pronounced structural and functional disorders of ischemic genesis develop in the organism and in the extremity within the next day. In case of primary adhesion of the soft tissue wound in the zone of collateral pathways or distinctly limited foci of purulent wound infection in any topography of wound canal acute arterial insufficiency is compensated due to mobilization of all vascular reserves. These are primarily arteries of remaining muscles and nerves, cutaneofascial vessels and arterial bed of the opposite extremity as well. On contrary, wound suppuration sharply suppresses vessel plastic properties, promotes tissue necrosis, including ischemic gangrene of the extremity distant segments. Basic dogma of anatomic experimental studies were supported by clinico-physiological evaluation of collateral circulation in the 16 wounded with vascular disturbances.     

Ways to increase the service life of metal members of hydraulic structures

Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 1, pp. 34–36, January, 1990.     

Kinetics of leaching of lead sulfate in sodium chloride solutions

A powder dissolution method is used to study the kinetics of leaching of lead sulfate from a lead cake in the temperature range 298–353 K and the concentration range 50–270 g/l of a sodium chloride solution. The results obtained are used to calculate the apparent activation energy (E _a = 12.41 kJ/mol); its value indicates that the process of leaching of lead sulfate from a lead cake occurs in a diffusion zone. This process is shown to be described by a first-order kinetic equation.