The condensation of complex silicates with pyroxene and olivine composition under conditions prevailing in molecular clouds has been experimentally studied. For this purpose, molecular species comprising refractory elements were forced to accrete on cold substrates representing the cold surfaces of surviving dust grains in the interstellar medium. The efficient formation of amorphous and homogeneous magnesium iron silicates at temperatures of about 12 K has been monitored by IR spectroscopy. The gaseous precursors of such condensation processes in the interstellar medium are formed by erosion of dust grains in supernova shock waves. In the laboratory, we have evaporated glassy silicate dust analogs and embedded the released species in neon ice matrices that have been studied spectroscopically to identify the molecular precursors of the condensing solid silicates. A sound coincidence between the 10 microm band of the interstellar silicates and the 10 microm band of the low-temperature siliceous condensates can be noted.
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http://dx.doi.org/10.1039/c4fd00010b | DOI Listing |
Materials (Basel)
December 2024
Institute of Civil Engineering and Architecture, National University of Water and Environmental Engineering, 33028 Rivne, Ukraine.
By volume, cement concrete is one of the most widely used construction materials in the world. This requires a significant amount of Portland cement, and the cement industry, in turn, causes a significant amount of CO emissions. Therefore, the development of concrete with a reduced cement content is becoming an urgent problem for countries with a significant level of production and consumption of concrete.
View Article and Find Full Text PDFJ Phys Chem A
January 2025
Department of Chemistry, Lomonosov Moscow State University, Moscow 119991 Russia.
The recent detection of benzonitrile (CHCN) in the interstellar medium is one of the most fascinating discoveries in astrochemistry and molecular astrophysics. However, the mechanism of its formation in interstellar ices remains unclear. Here, we report the first evidence for the direct synthesis of benzonitrile through the radiation-induced transformations of an isolated CH···HCN complex in inert rigid media at cryogenic temperature (4.
View Article and Find Full Text PDFEnviron Geochem Health
December 2024
Department of Microbiology, Institute of Quality Sciences and Product Management, Krakow University of Economics, Sienkiewicza 4, 30-033, Krakow, Poland.
Total concentrations, toxicity, and health risks of 16 polycyclic aromatic hydrocarbons (PAH) in street dust from Warsaw (Poland) in 6 granulometric fractions were investigated. Street dust was collected from 149 sampling points distributed among Area 1 (central districts, left bank of the Vistula River, mostly traffic-related pollution) and Area 2&3 (suburb area, mostly residential, right bank of the river). Street dust was investigated before ("all") and after separating into 5 size-dependent samples: (1-0.
View Article and Find Full Text PDFMaterials (Basel)
November 2024
Department of Applied Geology, Faculty of Mining, Safety Engineering and Industrial Automation, Silesian University of Technology, Akademicka 2, 44-100 Gliwice, Poland.
The recycling of used lead-acid batteries is currently the main source of lead in the world. More than 50% of the weight of a used lead-acid battery is battery paste, in which lead occurs in compounds with oxygen and sulfur. In pyrometallurgical processes of battery paste, coke or coke breeze is used as a traditional additive acting as a fuel/reducer.
View Article and Find Full Text PDFAstrobiology
December 2024
Solar System Exploration Division, NASA Goddard Space Flight Center, Greenbelt, Maryland, USA.
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