INFLUENCE OF DETONATION PRESSURE OF EXPLOSIVE COMPOSITIONS ON HEAT OF EXPLOSION

К настоящему времени накоплен большой объём калориметрических данных о теплоте (энергии) взрыва Q различных взрывчатых веществ (ВВ) и взрывчатых составов (ВС). Получены зависимости Q от начальной плотности ВВ Q(ρ0). Однако, на практике давление детонации в основном заряде можно менять, вызывая пересжатую детонацию, за счёт инициирования основного заряда мощным ВВ, поэтому практический интерес представляют зависимости теплоты взрыва от давления детонации Q(Р), которые можно получить на основе имеющихся зависимостей Q(ρ0) для индивидуальных ВВ, распространив их на ВС. Приведена методика определения зависимостей для расчёта теплоты взрыва различных ВС, включая алюминийсодержащие, как при нормальной так и при пересжатой детонации A large volume of calorimetric data on the heat energy Q of explosion for various explosives (Es) and explosive compositions (EC) has been accumulated by now. The dependences of Q on the initial ES density Q (ρ0) are obtained. However, the detonation pressure in the base charge can be changed in practice causing super compressed detonation, due to the initiation of the base charge by a powerful explosive; therefore, the dependences of the explosion heat on the detonation pressure Q (P), which can be obtained on the basis of the available dependences Q (ρ0) for individual explosives is of practical interest as they can be applied to EC. A method to determine the dependences for calculating the heat of explosion of various aircraft, including aluminum-containing ones, both during normal and super compressed detonation is presented.

Heats of combustion of the main carbohydrates contained in plant-source foods

In a previous review, the experiments of American chemist W.O. Atwater were critically examined, with the findings demonstrating certain weaknesses that could compromise the validity of the values currently used for metabolizable energy. An examination of published works on the heat of combustion of carbohydrates reveals 2 types of weaknesses: the inaccuracy and imprecision of the calorimetric data used, and the averaging procedure employed to estimate such representative values. The present review focuses on the first type of weakness, namely the inaccuracy and imprecision of the calorimetric data used in previous studies. An exhaustive bibliographic search yielded almost 100 heat of combustion values for some of the 6 main carbohydrates contained in plant-source foods (glucose, fructose, sucrose, maltose, starch, and cellulose). These heats of combustion were subjected to rigorous statistical analysis to propose the following for each carbohydrate: (1) an interval (termed a bibliographic interval) that very likely includes the actual heat of combustion value and (2) a “representative value” (calculated to produce the minimum level of inaccuracy). In addition, an estimation of the maximum level of inaccuracy that could be expected when using such a representative value is reported.

A Review on Heat Released in early Geopolymerization by Calorimetric Study

An exothermic chemical reaction between cement and water or is called as hydration of cement produced heat in which gives significance impact to the cement or concrete produced. This hydration of cement is similar to geopolymerization as in geopolymerization, heat is liberated when any pozzolanic material mixes with alkaline solution. Heat released for both hydration of cement and geopolymerization can be measured in a form of calorimetric data. This paper reviews on the use of heat released information for a better understanding on the reaction kinetics of geopolymerization and correlating the heat released with several factors including concentration of alkaline solution, mixing designation and curing temperature.