This article describes the production of unsupported nickel phosphide catalysts generated in situ in а reaction mixture from water-soluble and oil-soluble precursors during the hydroconversion of ...levulinic acid. These catalysts contain crystalline phases, specifically Ni
12
P
5
and Ni(PO
3
)
2
. During the hydrogenation of levulinic acid in toluene in the presence of NiP–TOP, a lower temperature and a shorter reaction time contribute to the formation of γ-valerolactone (100% selectivity). A higher temperature and a longer reaction time favor the formation of valeric acid (94% selectivity). In the hydrogenation of levulinic acid in ethanol in the presence of NiP–H
3
PO
2
, the main reaction product is ethyl levulinate (95% selectivity).
The review presents modern domestic and foreign published data on the blood plasma protein haptoglobin, its structure, synthesis, function, and interaction with hemoglobin. The ability of haptoglobin ...in interaction with hemoglobin to reduce the toxic effect of the latter is shown. Clinical studies of such interaction in various pathological conditions such as diabetes mellitus, sickle cell anemia, malaria, and sepsis are described. It is noted that the development of new haptoglobin derivatives can contribute to the prevention of hemoglobin toxicity in hemolytic diseases.
This is a review of data on the impact of COVID-19 on blood clotting. An important feature of the pathogenesis of severe acute respiratory syndrome caused by the SARS-Co-2 coronavirus is the risk of ...thrombotic complications including microvascular thrombosis, venous thromboembolism, and stroke. These thrombotic complications, like thrombocytopenia, are markers of the severe form of COVID-19 and are associated with multiple organ failure and increased mortality. One of the central mechanisms of this pathology is dysregulation of the adhesive protein P-selectin. The study of the mechanisms of changes in hemostasis and vascular pathology, and the role in these processes of biomarkers of thrombogenesis, and primarily of P-selectin of various origins (platelets, endothelial cells, and plasma), can bring some clarity to the understanding of the pathogenesis and therapy of COVID-19.
The active use of transition metal phosphides in catalysis commenced at the beginning of the 2000s primarily in hydrodesulfurization and hydrodenitrogenation reactions. Owing to an increased interest ...in biomass-based feedstocks the intensive use of phosphides in hydrodeoxygenation reactions started in the first part of the 2010s. In earlier reviews devoted to phosphides, which were published before the 2010s, no information pertaining to hydrodeoxygenation is available. This review addresses monometallic phosphides of such transition metals as nickel, cobalt, molybdenum, and tungsten and covers their structure, synthesis, and properties. Transition metal phosphides are promising catalysts for hydroprocesses. They possess both metal active sites and acid sites, and, therefore, demonstrate activity not only in hydrogenation but in a number of acid-catalyzed processes. The review concerns the hydrodeoxygenation reactions of higher fatty acids and their esters; vegetable oils; and bio-oil and its model compounds. The hydrotreatment of vegetable oils and their derivatives over phosphides makes it possible to obtain hydrocarbons, which can be used as diesel fuel components or as a pure fuel. Using the hydrodeoxygenation of bio-oil model compounds catalyzed by phosphides partially or fully deoxygenated products may be obtained; however, the hydrotreatment of bio-oil itself did not provided positive results so far and calls for further research.
Published data on hydrodesulfurization and hydrodenitrogenation of model petroleum compounds in the presence of molybdenum and tungsten phosphides are analyzed. The majority of papers in which these ...catalysts are compared to traditional sulfide catalysts demonstrate higher activity of the phosphide catalysts. The influence exerted on the activity of phosphide catalysts in these processes by the feed composition (presence of sulfur- and nitrogen-containing compounds), catalyst synthesis conditions and active phase content, reaction conditions, and promoter is described. When performing the synthesis at high temperatures or using large amounts of the active phase deposited onto an Al-containing support, the catalyst activity can decrease owing to the formation of AlPO
4
. The promotion of molybdenum and tungsten phosphides with nickel or cobalt enhances the catalyst activity. The major cause of phosphide deactivation is the presence of nitrogen-containing compounds in the feed, whereas the presence of sulfur-containing compounds, on the contrary, in most cases leads to an increase in the catalyst activity owing to the formation of the phosphosulfide phase.
INTRODUCTION:
The expansion of the community of states with independence of former European colonies in Latin America was a new historical fact that contributed to the evolution of international law. ...On the basis of Latin American doctrinal thought and international diplomatic practice the principles enshrined today in universal international legal acts were proclaimed. International law is often viewed from a Eurocentric point of view, with such a position little attention is paid to the influence of Latin American doctrine on the development of international law at the universal level. Therefore, it seems appropriate to highlight the question - in a historical retrospective - about the contribution of Latin American states to the formation of international law and international legal consciousness.
MATERIALS AND METHODS:
The materials for the study were the international legal norms of universal and regional nature, the works of national and Latin American scientists. When writing the article, general and particular scientific methods were used, namely, deduction and induction, analysis and synthesis, the historical method.
RESEARCH RESULTS:
The article reveals the origins of the doctrines of international law developed by Latin American authoritative international lawyers, state and political figures in the XIX-XX centuries. These doctrines had a significant impact on the formation and development of international law not only in the Latin American region, but also in the world as a whole, influenced the development of positions of Latin American states in the international arena.
DISCUSSION AND CONCLUSIONS
: The article substantiates the conclusion that it is necessary to consider modern international law, taking into account the significant contribution of Latin American states to its evolution at the universal level; reveals the interconnection of the principles in the doctrines of Latin American lawyers and state figures that were included in the system of international law at the universal level.
A statistical method for extracting the η → γγ signal upon rejecting those γ clusters that form pairs with invariant masses close to that of the π
0
meson is proposed. The η selection efficiency (the ...ratio between the numbers of selected and produced η mesons) and the signal-to-background ratio as a function of the η transverse momentum are obtained using a template of proton–proton collisions at
= 13 TeV simulated with PYTHIA 8.2 (with Monash-2013 tuning). The proposed method provides for an η → γγ selection efficiency of ~80% and for a 20–50% increase in the signal-to-background ratio compared to currently implemented techniques.
Unsupported phosphide catalysts of composition Ni
2
P and CoP are prepared in situ in the reaction medium from oil-soluble precursors in the course of hydrodeoxygenation of palmitic and stearic ...acids. The obtained catalysts are characterized by X-ray powder diffraction and X-ray photoelectron spectroscopy; they show high activity in the hydrodeoxygenation of model substrates. After 6 h of the hydrodeoxygenation reactions, the conversion of palmitic acid reaches 93 and 92% and the conversion of stearic acid is as high as 94 and 91% in the presence of nickel phosphide and cobalt phosphide, respectively. It is shown that the catalyst formed in situ can be isolated and recycled.
Amorphous catalysts based on molybdenum and tungsten phosphides were prepared
in situ
from oil-soluble precursors such as triphenylphosphine and carbonyls of the corresponding metals during ...hydrodeoxygenation of guaiacol. These catalysts were characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, extended X-ray absorption fine structure spectroscopy, and transmission electron microscopy. After 6 h of reaction at 320–380°C and an initial hydrogen pressure of 5 MPa, the guaiacol conversion amounted to 89–91% in the presence of the molybdenum phosphide catalyst and 80–86% with tungsten phosphide. The selectivity towards phenol as the main reaction product reached as high as 80% in the presence of molybdenum phosphide (360°C, 6 h) and 78% in the tungsten phosphide case (340°C, 1 h). In the presence of both catalytic systems, the reaction products also contained anisole, cresols, and toluene.
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