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Sergeysmirnovite, MgZn2(PO4)2 · 4H2O, is a new mineral from the oxidation zone of the Kester mineral deposit, Sakha-Yakutia, Russia. This mineral forms tabular colorless crystals growing on quartz and fluorapatite aggregates in association with pseudomalachite, libethenite, native copper, a Na-analogue of batagayite, arsenolite, tobermorite, epifanovite, and batagayite. The mineral is orthorhombic, with the space group Pnma. The unit cell parameters refined from powder X-ray diffraction data are the following: a = 10.5957(6) Å, b = 18.365(1) Å, c = 5.0320(4) Å, V = 979.16 (8) Å3. The eight most intense powder X-ray diffraction lines are the following (I-d[Å]-hkl): 100-5.28-200; 33-4.576-040; 24-3.999-230; 24-3.877-031; 22-3.387-221; 44-3.015-250; 57-2.854-311; 34-2.647-400. Sergeysmirnovite belongs to the hopeite group and is dimorphous with reaphookhillite. The mineral is named in honor of famous Soviet geologist, Academician Sergei Sergeevich Smirnov (1895–1947), a renowned specialist in the mineralogy of ore deposits. [ABSTRACT FROM AUTHOR]

The problem of using octanometers for the rapid control of the octane number of compounds in the production of commercial gasoline is considered, and the factors forming it are indicated. Error spectra of a multidimensional absorption spectral analytic signal of commercial gasolines and compounds of their individual fractions (components) were studied in measurements in the mid-IR region. The effect of a change of the proportion of the main constituents (aromatic hydrocarbons, benzene catalysate, isomerizate, methyl tert-butyl ether, and isopentane) in the compound on the spectra of commercial gasolines was evaluated. Multidimensional measurements of light absorption by gasolines in a wide spectral region and difference spectra were used. It was shown that spectral noise does not form limitations in spectroscopic measurements, while uncontrollable variations in the process conditions can form significant deviations in the absorption spectra, leading to problems in using calibration characteristics based on commercial gasoline samples. [ABSTRACT FROM AUTHOR]

To assess a possibility of the measurement of the relative concentration of main gasoline components under varied conditions, we studied the absorption of electromagnetic radiation by these components in the mid-IR region. The results for the absorbance of gasoline with varying concentrations of components, obtained using Fourier-transform IR spectroscopy are presented. The use of multidimensional difference spectra of gasoline is the most effective and informative way to perform measurements. The high sensitivity of the difference spectra to changes in the composition and concentrations of the main gasoline components is demonstrated. [ABSTRACT FROM AUTHOR]