Cerium sulfide pigments

Cerium sulfide pigments belong to the inorganic orange and red pigments. They were developed to substitute cadmium and lead containing red and orange colored pigments, in particular in plastics. Cerium(III) sulfide exists in three allotropic modifications, but only γ-Ce2S3, which is colored dark red, is suitable for the use as a pigment. Cerium sulfide pigments are characterized by high color strength, strong hiding power and sufficient thermal stability. Their limited stability in water containing systems and in humid atmospheres is not without problems. The pigments tend to degradation in the presence of water or humidity to form hydrogen sulfide, which limits the application possibilities significantly.

Аллотропные модификации кобальта при химическом осаждении

The effect of the acidity of solutions on the crystal structure of cobalt during its chemical precipitation is reported. On the basis of structural, magnetic studies, as well as studies by nuclear magnetic resonance, it was shown that a change in the acidity of the working solution leads to the precipitation of cobalt in various allotropic modifications in the immediate environment: by the type of hcp in the region of small (up to ~ 8.5) and by the type of fcc in the region large (over ~ 8.5) pH values. The formation of these modifications of cobalt is associated with size effects, which are caused by a decrease in the size of its particles with increasing pH.

Memory Effect in the Spatial Series Based on Diamond and Graphite Crystals

To study the relation between the structure of a compound and its properties is one of the fundamental trends in chemistry and materials science. A classic example is the well-known influence of the structures of diamond and graphite on their physicochemical properties, in particular, hardness. However, some other properties of these allotropic modifications of carbon, e.g., fractal properties, are poorly understood. In this work, the spatial series (interatomic distance histograms) calculated using the crystal structures of diamond and graphite are investigated. Hurst exponents H are estimated using detrended fluctuation analysis and power spectral density. The values of H are found to be 0.27–0.32 and 0.37–0.42 for diamond and graphite, respectively. The calculated data suggest that the spatial series have long memory with a negative correlation between the terms of the series; that is, they are antipersistent.

Structure formation in diamond powder during chemical infiltration from the gas phase

In this paper was investigated effect of pumping a mixture of methane and hydrogen in a microwave discharge through layers of diamond powder on structure formation sediment during chemical infiltration from the gas phase. The infiltration process was implemented on the conditions of gas pumping through the layers of diamond powder, in the presence of a plasma discharge over the samples. It is established that in contempt of the size of the diamond powder, the growth of diamond from the gas phase occurs on the surface of the first layer, the growth of diamond from the gas phase stops when the second layer starts, and different allotropic modifications of carbon start to grow, in particular nanocrystalline graphite, carbon nanotubes, and graphite. Such a rapid transition between diamond growth and the growth of various allotropic carbon modifications is related with the screening of the plasma discharge by the first layer of diamond powder. Thus, the absence of direct contact of the microwave plasma discharge with the formed molecular hydrogen during its recombination leads to the fact that the concentration of atomic hydrogen is low to maintain the growth of diamond from the gas phase inside the layer of diamond powder.

The Spermine Phosphate-Bound Cyclooctaoxygen Sodium Epigenetic Shell of Euchromatin DNA Is Destroyed by the Epigenetic Poison Glyphosate

Oxygen exists in two gaseous and six solid allotropic modifications. An additional allotropic modification of oxygen, the cyclooctaoxygen, was predicted to exist in 1990. The first synthesis and characterization of cyclooctaoxygen as its sodium crown complex, isolated in the form of three cytosine nucleoside hydrochloride complexes, was reported in 2016. Cyclooctaoxygen sodium was synthesized from atmospheric oxygen, or catalase effect-generated oxygen, under catalysis of cytosine nucleosides and either ninhydrin or eukaryotic low-molecular weight RNA. The cationic cyclooctaoxygen sodium complex was shown to bind RNA and DNA, to associate with single-stranded DNA and spermine phosphate, and to be essentially non-toxic to cultured mammalian cells at 0.1–1.0 mM concentration. We postulated that cyclooctaoxygen is formed in most eukaryotic cells from dihydrogen peroxide in a catalase reaction catalysed by cytidine and RNA. A molecular biological model was deduced for a first epigenetic shell of eukaryotic euchromatin. This model incorporates an epigenetic explanation for the interactions of the essential micronutrient selenium (as selenite) with eukaryotic euchromatin. The sperminium phosphate/cyclooctaoxygen sodium complex is calculated to cover the actively transcribed regions (2.6%) of bovine lymphocyte interphase genome. Cyclooctaoxygen seems to be naturally absent in hypoxia-induced highly condensed chromatin, taken as a model for eukaryotic metaphase/anaphase/early telophase mitotic chromatin. We hence propose that the cyclooctaoxygen sodium-bridged spermine phosphate and selenite coverage serves as an epigenetic shell of actively transcribed gene regions in eukaryotic ‘open’ euchromatin DNA. The total herbicide glyphosate (ROUNDUP) and its metabolite (aminomethyl)phosphonic acid (AMPA) are proved to represent ‘epigenetic poisons’, since they both selectively destroy the cyclooctaoxygen sodium complex. This definition is of reason, since the destruction of cyclooctaoxygen is sufficient to bring the protection shield of human euchromatin into collateral epigenetic collapse.