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111.
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In this paper, we identify and describe the active and inert horizons of oligotrophic bogs. These often appear to be a fire risk to oil and gas extraction industries, but these bogs are a complex biological system also. We describe three structural layers for the active horizon. These are the turf layer, the porous layer, the intermediate layer. We have investigated the morphological characteristics of these layers. For each layer, we gave the measurement of physical parameters – pH, general mineralisation, conductivity, coefficient of ash and moisture. In each selected layer we study microbiological parameters – microbial biomass, the carbon of microbial biomass, basal respiration and microbial metabolic quotient. Microbiological studies have established the boundary between the aerobic and anaerobic conditions in active layer of oligotrophic bogs. In each layer, we have established the biochemical characteristics of layers studying enzymes catalase and invertase. The obtained data make it possible to assess the functional processes in the active horizon of the wetland’s ecosystem.  相似文献   
114.
A variety of the ternary Hf–Ir–B phases formed via the reaction between iridium and hafnium diboride at elevated temperatures was found. The data on the phase and elemental composition, as well as crystal structure, obtained by powder and single-crystal X-ray diffraction, scanning electron microscopy/energy-dispersive X-ray spectrometer, and time-of-flight neutron diffraction analysis unambiguously confirm that HfIr3Bx solid solution, two known ternary borides (HfIr3B4, Hf2Ir5B2), as well as two novel ternary HfIr2.1B1.3 and HfIr5.7B2.7 phases, are formed at elevated temperatures. This result is fundamentally different from that previously obtained by us for the Hf–Ir–C system in which only one binary intermetallic compound, HfIr3, was produced. The measured Vickers microhardness for all the aforementioned ternary borides (13–19 GPa) allows us to consider them hard. The coefficients of thermal expansion of ternary borides were measured by in situ high-temperature X-ray analysis.  相似文献   
115.
Polycystic ovarian syndrome (PCOS) is the most common endocrine–metabolic disorder affecting a vast population worldwide; it is linked with anovulation, mitochondrial dysfunctions and hormonal disbalance. Mutations in mtDNA have been identified in PCOS patients and likely play an important role in PCOS aetiology and pathogenesis; however, their causative role in PCOS development requires further investigation. As a low-grade chronic inflammation disease, PCOS patients have permanently elevated levels of inflammatory markers (TNF-α, CRP, IL-6, IL-8, IL-18). In this review, we summarise recent data regarding the role of mtDNA mutations and mitochondrial malfunctions in PCOS pathogenesis. Furthermore, we discuss recent papers dedicated to the identification of novel biomarkers for early PCOS diagnosis. Finally, traditional and new mitochondria-targeted treatments are discussed. This review intends to emphasise the key role of oxidative stress and chronic inflammation in PCOS pathogenesis; however, the exact molecular mechanism is mostly unknown and requires further investigation.  相似文献   
116.
We study the waves at the interface between two thin horizontal layers of immiscible liquids subject to high-frequency tangential vibrations. Nonlinear governing equations are derived for the cases of two- and three-dimensional flows and arbitrary ratio of layer thicknesses. The derivation is performed within the framework of the long-wavelength approximation, which is relevant as the linear instability of a thin-layers system is long-wavelength. The dynamics of equations is integrable and the equations themselves can be compared to the Boussinesq equation for the gravity waves in shallow water, which allows one to compare the action of the vibrational field to the action of the gravity and its possible effective inversion.  相似文献   
117.
The interaction of two rigid cylinders with parallel axes in a viscous liquid subjected to translational vibrations perpendicular to the plane containing the cylinder axes is considered in the framework of the low Reynolds number approximation. It is shown that the interaction type substantially depends on the distance between the cylinders. If this distance exceeds the viscous Stokes length, then the vibrations lead to the cylinder attraction. For the distances shorter than the Stokes length, the behaviour is opposite.  相似文献   
118.
In this paper, we investigate the motion of a particle confined between the oscillating and fixed walls. As the particle collides with the moving wall in the phase of oscillations, when the wall velocity grows, the wall after collision catches up with the particle. This process can be repeated many times until in finite time interval the particle is found lying on the wall and continues its motion together with the wall. When the sign of the wall acceleration changes the particle detaches from the wall with zero velocity, so that it looks as if the particle “sticks” to the wall. It has been found that if the collision is inelastic, “sticking” leads to convergence of close trajectories except for the case of weak decay. On the contrary, in the case of elastic collision “sticking” of the particle causes even a more rapid divergence of theses trajectories.  相似文献   
119.
The fundamental roles of nucleoside triphosphates and nucleotide cofactors such as NAD+ in biochemistry are well known. In recent decades, continuing research has revealed the key role of 5′‐capped RNA and 5′,5′‐dinucleoside polyphosphates in the regulation of vitally important physiological processes. Last but not least, the commercial potential of nucleoside triphosphate synthesis can hardly be overestimated. Nevertheless, despite decades of investigation and the obvious topicality of the research on the chemical synthesis of the nucleotide compounds containing phosphate anhydride linkages, none of the existing procedures can be considered an up‐to‐date “gold standard”. However, there are a number of fruitful synthetic approaches to forming phosphate anhydride linkages in satisfactory yield. These are summarized in this concise review, organized by the type of active phosphorous intermediate and reagents used.  相似文献   
120.
We explored new approaches to replace the nitrogen atoms of arsenic, antimony, bismuth, and discovered a new paths to modify Raschig, Schiff, Andrusov, Hofmann, Colbe, Delepine reactions with arsine, stibine and bismuthine in organometallic chemistry. We have proposed a new mechanism for possible reactions.  相似文献   
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