Investigation of a CO2 extract of the fruit of Capsicum annuum

Summary The composition of a CO₂ extract of the fruit of the pepperCapsicum annuum L. with respect to the main classes of compounds has been studied. A method has been developed for the extraction and quantitative determination of capsaicine.Krasnodar Scientific-Research Institute of the Food Industry. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 481–485, July–August, 1974.     

Structural and functional diagnostics of ultrafine components in condensed high-energy systems

The study deals with octogen (HMX) and aluminum, which are among the most widely used components of condensed high-energy systems. The structure, thermal behavior and combustion parameters were determined for the octogen-based monofuels and octogen-aluminum binary systems at different dispersity of components. Irrespective of differences in thermal behavior, monofuels obtained with standard and ultrafine octogen powders were shown to have virtually identical combustion parameters. In the binary systems, replacement of standard microsized aluminum by ultrafine one increases the combustion rate by a factor of 2.5, and completeness of the metal reaction (oxidation) by a factor of 4.     

Nitro-, Cyano-, and Methylfuroxans,and Their Bis-Derivatives: From Green Primary to Melt-Cast Explosives

In the present work, we studied in detail the thermochemistry, thermal stability, mechanical sensitivity, and detonation performance for 20 nitro-, cyano-, and methyl derivatives of 1,2,5-oxadiazole-2-oxide (furoxan), along with their bis-derivatives. For all species studied, we also determined the reliable values of the gas-phase formation enthalpies using highly accurate multilevel procedures W2-F12 and/or W1-F12 in conjunction with the atomization energy approach and isodesmic reactions with the domain-based local pair natural orbital (DLPNO) modifications of the coupled-cluster techniques. Apart from this, we proposed reliable benchmark values of the formation enthalpies of furoxan and a number of its (azo)bis-derivatives. Additionally, we reported the previously unknown crystal structure of 3-cyano-4-nitrofuroxan. Among the monocyclic compounds, 3-nitro-4-cyclopropyl and dicyano derivatives of furoxan outperformed trinitrotoluene, a benchmark melt-cast explosive, exhibited decent thermal stability (decomposition temperature >200 °C) and insensitivity to mechanical stimuli while having notable volatility and low melting points. In turn, 4,4′-azobis-dicarbamoyl furoxan is proposed as a substitute of pentaerythritol tetranitrate, a benchmark brisant high explosive. Finally, the application prospects of 3,3′-azobis-dinitro furoxan, one of the most powerful energetic materials synthesized up to date, are limited due to the tremendously high mechanical sensitivity of this compound. Overall, the investigated derivatives of furoxan comprise multipurpose green energetic materials, including primary, secondary, melt-cast, low-sensitive explosives, and an energetic liquid.     

High-energy 4(10)-2-fluoro-2,2-dinitroethyl and 4(10)-2,2-dinitropropyl derivatives of polynitrohexaazaisowurtzitanes

Russian Chemical Bulletin - Methods for the syntheses of a series of high-energy 4(10)-2-fluoro-2,2-dinitroethyl and 4(10)-2,2-dinitroethyl derivatives of polynitrohexaazaisowurtzitanes were...     

General principles of enzymatic methods and their use in the determination of the radiochemical purity of mono-and disaccharides labelled with14C

General principles of enzymatic methods for the determination of radiochemical purity of natural¹⁴C-mono-and-disaccharides are suggested, and analytical schemes using these principles have been worked out. The enzymatic method of determining the radiochemical purity of¹⁴C-glucose is given as an illustration.     

The structure of particles and combustion parameters of compositions with nanoaluminum

Aluminum nanoparticles modified with various additives (Ba, gasoline, and organosilicon resin) were obtained by arc plasma recondensation. The chemical composition, morphology, and thermal properties of nanoparticles and the characteristics of combustion of energy-producing condensed systems containing nanoaluminum were studied experimentally. The structure of the particles was determined by X-ray diffraction (a Rigaku Geigerflex diffractometer), transmission electron microscopy (JEM 2000 EX-II), scanning electron microscopy (JEOL JSM 7401F), atomic force microscopy (SOLVER P-47), and differential scanning calorimetry (NETZSCH STA 409). The replacement of aluminum powder with micron particles with nanodisperse aluminum increased the rate of combustion of stoichiometric compositions on the basis of ammonium perchlorate by an order of magnitude at a pressure of 40 atm. Simultaneously, the mean linear diameter of agglomerates collected from the surface of combustion decreased from 28 to 2 μm. The results are evidence that the use of energy-producing condensed compositions with nanoaluminum offers much promise for increasing the effectiveness of solid fuel rocket engines.