Singers in Russian Military Choir Among 92 Feared Dead After Plane Crashes Into Black Sea. Russian Military Plane Crashes into Sea. Shortly after takeoff on Sunday morning, a Russian military plane carrying 92 people crashed into the Black Sea near Sochi.
Keywords: chloride in concrete, near-infrared spectrometry, rapid determination. 1. INTRODUCTION. 1.1 Background. Penetration of chloride ions into concrete is a well-known problem, because it eventually results in. corrosion of rebars, leading to cracks, spalling, delamination and other roadway defects [1]. The problem is. particularly acute in bridge decks, which are subject to frequent salt applications during the winter months.
Calcium nitrate is used in set accelerating concrete admixtures. This use with concrete and mortar is based on two effects. The calcium ion accelerates formation of calcium hydroxide and thus precipitation and setting. This effect is used also in cold weather concreting agents as well as some combined plasticizers.The nitrate ion leads to formation of iron hydroxide, whose protective layer reduces corrosion of the concrete reinforcement.he calcium ion accelerates formation of calcium hydroxide and thus precipitation and setting. This effect is used also in cold weather concreting agents as well as some combined plasticizers. The nitrate ion leads to formation of iron hydroxide, whose protective layer reduces corrosion of the concrete reinforcement.