Basic Reaction Research Articles

Is Aesthetic Good? A Study on the Aesthetic and Vitality Judgment of Pictorial Representations of the Dead, Saints and Non-Saints.

In the history of the Western world, there has always been an association between good and beautiful. Starting from a brief history of beauty, two questions arise: is beauty linked to good even in art? How important are people's religious beliefs in aesthetic and vitality judgments? The psychology of art could answer these questions by studying people's reactions to the images of Saints as testimonials of goodness. Moreover, the study of Saints' paintings would allow us to investigate vitality, understood as one's perception of a living being. The research aimed to investigate the aesthetic and vitality judgments of faces representing the dead, Saints and non-Saints. More than a hundred participants were asked to evaluate the aesthetics and vitality of these paintings; moreover, two tests assessing spirituality and religiosity were administered. Overall, these data suggest Saints were judged more beautiful than non-Saints, and non-Saints were judged more vital than Saints. This might suggest a relationship between ethics and aesthetics, also in the perception of art, and offers reflections on the theme of vitality. The religion and spirituality of participants are not correlated to aesthetic or vitality judgments; this fact could support that these judgments are linked to the basic bottom-up reactions to images.

SYNTHESIS OF MEMANTINE HYDROCHLORIDE BY DIRECT AMINOATION OF 1-BROMO-3,5-DIMETHYLADAMANTANE WITH

Objectives: To optimize the synthesis process of memantine hydrochloride by direct aminoation of 1-bromo-3,5-dimethyladamantane with urea. Materials and methods: Using the basic chemical reactions to optimize the reaction conditions. Results: The optimal conditions of the memantine hydrochloride synthesis process include: The reaction solution was diphenyl ether; the reaction temperature was 170oC within 4 hours (in the first step) and 100oC within 2 hours (in the second step); the molar ration of 1-bromo-3,5-dimethyladmantane: urea: diphenyl ether was 1:3:2.5; the duration of the reaction was 6 hours and the overall yields were 75.81%. Conclusion: The synthesis process of memantine hydrochloride by direct aminoation with urea was established. The finished products were determined by IR, MS, and NMR spectra and met the standards of USP 43.

Status and perspectives of key materials for PEM electrolyzer

Proton exchange membrane water electrolyzer (PEMWE) represents a promising technology for the sustainable production of hydrogen, which is capable of efficiently coupling to intermittent electricity from renewable energy sources (e.g., solar and wind). The technology with compact stack structure has many notable advantages, including large current density, high hydrogen purity, and great conversion efficiency. However, the use of expensive electrocatalysts and construction materials leads to high hydrogen production costs and limited application. In this review, recent advances made in key materials of PEMWE are summarized. First, we present a brief overview about the basic principles, thermodynamics, and reaction kinetics of PEMWE. We then describe the cell components of PEMWE and their respective functions, as well as discuss the research status of key materials such as membrane, electrocatalysts, membrane electrode assemblies, gas diffusion layer, and bipolar plate. We also attempt to clarify the degradation mechanisms of PEMWE under a real operating environment, including catalyst degradation, membrane degradation, bipolar plate degradation, and gas diffusion layer degradation. We finally propose several future directions for developing PEMWE through devoting more efforts to the key materials.

A carbon cloth interlayer immobilizes carbon nanotube-supported ternary chalcogen compounds in novel lithium-chalcogenide batteries

The development of lithium-chalcogen batteries containing one active species is limited by bottlenecks. Multichalcogen composites that integrate the advantages of each component while avoiding their defects are desired. Herein, carbon nanotubes (CNT) and carboxylated-CNT (CCNT) are adopted as carriers for active substances consisting of S, Se, and Te at a feed ratio of 8:1:1 (SST811). The electrochemical performance of SST811/CCNT is better than that of SST811/CNT because CCNT contains more oxygen-containing functional groups, allowing the active species to be firmly anchored. Cyclic voltammetry (CV) curves, charge-discharge profiles and in-situ Raman results reveal the solid-phase charge-discharge mechanism of SST811/CCNT in ester electrolyte, consisting of a combination of basic reaction steps. To suppress the shedding of active species during long cycling, a carbon cloth (CC) interlayer is introduced between cathode and separator without altering the inherent reaction mechanism of SST811/CCNT. Under the protection of CC interlayer, the capacity of SST811/CCNT remains at 1219.2 mAh g−1 after 300 cycles, which is 1.5 times that without interlayer. The protective effect of CC interlayer is demonstrated by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman results. This work inspires the further development of lithium-chalcogenide batteries.

The maximum entropy principle for compositional data

BackgroundCompositional systems, represented as parts of some whole, are ubiquitous. They encompass the abundances of proteins in a cell, the distribution of organisms in nature, and the stoichiometry of the most basic chemical reactions. Thus, a central goal is to understand how such processes emerge from the behaviors of their components and their pairwise interactions. Such a study, however, is challenging for two key reasons. Firstly, such systems are complex and depend, often stochastically, on their constituent parts. Secondly, the data lie on a simplex which influences their correlations.ResultsTo resolve both of these issues, we provide a general and data-driven modeling tool for compositional systems called Compositional Maximum Entropy (CME). By integrating the prior geometric structure of compositions with sample-specific information, CME infers the underlying multivariate relationships between the constituent components. We provide two proofs of principle. First, we measure the relative abundances of different bacteria and infer how they interact. Second, we show that our method outperforms a common alternative for the extraction of gene-gene interactions in triple-negative breast cancer.ConclusionsCME provides novel and biologically-intuitive insights and is promising as a comprehensive quantitative framework for compositional data.

Preclinical study of the effects of vitamin-mineral complex use during normal pregnancy in white rats

Vitamin-mineral deficiency is quite common in the world, which negatively affects the growth and development of children, provokes the development of chronic pathologies, allergic conditions. Children and pregnant women are particularly sensitive to this condition. Considering the vitamin and elemental composition of each of the drugs, it becomes necessary to examine the effect of various complexes on the body. The purpose of the study is to examine the morphological state of organs from the use of a vitamin-mineral complex during normal pregnancy in white rats and their offspring and examine the elemental analysis of target organs and whole blood. The experiment was conducted on pregnant female white laboratory rats and their offspring to achieve this goal. Histological, ultramicroscopic, morphometric, atomic-absorptic, functional methods, and statistical analysis are used for the study. A positive effect of the vitamin-mineral complex of the selected composition on both pre- and postnatal development of offspring is identified. The average offspring rate increased by 9.79% (p = 0.0443), while the stillbirth rate decreased by 81.82% (p = 0.0324). The absence of negative side effects of the complex on the development of basic reflex and behavioural reactions, motor activity, and cognitive activity of offspring is proved. A positive effect on the morphological characteristics of the liver, brain, heart, and kidneys is evident: the number of full hepatocytes in mature animals increased by 8.17% (p = 0.0482), and in young animals – by 5.03% (p = 0.0137), in the brain tissue of 7-day-old animals, the number of neurons increased by 7.70% (p = 0.0438), and the number of functionally defective neurons decreased. Microelement analysis of organs identified a tendency to increase the amount of a number of trace elements, which was reflected in the improvement of the antioxidant systems pf the body. A positive effect of the complex on the processes of hematopoiesis is noted. The results obtained can become morphological evidence for the choice of correction of macro-, microelement, and vitamin balance, prevention of its deficiency in pregnant women, and prevention of the development of deficient conditions in infants

Hot corrosion behavior of double-phase Nd2Zr2O7-YSZ thermal barrier coatings

This study investigated the hot corrosion behavior of various Nd2Zr2O7-yttria-stabilized zirconia (YSZ) thermal barrier coatings. Double-phase top coatings containing 25, 50, or 75 wt% Nd2Zr2O7 and functionally graded systems (FGS) comprising Nd2Zr2O7-YSZ were deposited on a substrate using an atmospheric plasma spraying method. The coatings were examined in terms of their exposure to pure Na2SO4 at 920, 970, and 1000 °C. The results indicate that in FGS, only neodymium sulfates and chromite are formed on the topcoat surface. In contrast, with dual-phase coatings containing Nd2Zr2O7 + YSZ, the diffusive decomposition of the pyrochlore Nd2Zr2O7 phase generated zirconate phases with lower neodymium contents and fluorite structure. The mechanism of pyrochlore phase decomposition is governed by basic and acidic reactions involving Na2SO4 decomposition products.

Make or break: the thermodynamic equilibrium of polyphosphate kinase-catalysed reactions.

Polyphosphate kinases (PPKs) have become popular biocatalysts for nucleotide 5'-triphosphate (NTP) synthesis and regeneration. Two unrelated families are described: PPK1 and PPK2. They are structurally unrelated and use different catalytic mechanisms. PPK1 enzymes prefer the usage of adenosine 5'-triphosphate (ATP) for polyphosphate (polyP) synthesis while PPK2 enzymes favour the reverse reaction. With the emerging use of PPK enzymes in biosynthesis, a deeper understanding of the enzymes and their thermodynamic reaction course is of need, especially in comparison to other kinases. Here, we tested four PPKs from different organisms under the same conditions without any coupling reactions. In comparison to other kinases using phosphate donors with comparably higher phosphate transfer potentials that are characterised by reaction yields close to full conversion, the PPK-catalysed reaction reaches an equilibrium in which about 30% ADP is left. These results were obtained for PPK1 and PPK2 enzymes, and are supported by theoretical data on the basic reaction. At high concentrations of substrate, the different kinetic preferences of PPK1 and PPK2 can be observed. The implications of these results for the application of PPKs in chemical synthesis and as enzymes for ATP regeneration systems are discussed.

Stepwise sulfurization of MoO3 to MoS2 thin films studied by real-time X-ray scattering

Chemical vapor deposition (CVD) is commonly used for the large-scale synthesis of the films of two-dimensional (2D) transition metal dichalcogenide (TMD) materials, including MoS2 thin films, which have potential applications in optoelectronics, catalysis, and nanoelectronics. As far as thin film of MoS2 is concerned, the influence of deposition parameters on the chemical reactions in the growth process via CVD synthesis has not yet been exhaustively studied. Here we present a comprehensive, time-resolved, in-situ study of the growth of MoS2 thin film from MoO3 by sulfurization using the grazing-incidence wide-angle X-ray scattering (GIWAXS) in laboratory conditions. We tracked the basic chemical reactions during the sulfurization process in real time by monitoring the phase transformations of MoO3 to MoO2 and MoO2 to MoS2 via a MoOS2 transient phase, although it was not possible to observe it directly. Preferential crystallographic orientation of MoO3, and MoO2 phases during the growth was confirmed. In addition, their activation energies were determined from the crystallization kinetics parameters. The present work highlights the importance of understanding the basic chemical reactions inside the CVD reactor as a prerequisite for optimizing the properties of the final 2D TMD films.

Hydrogen production by methane pyrolysis in molten binary copper alloys

The utilization of hydrogen as an energy carrier and reduction agent in important industrial sectors is considered a key parameter on the way to a sustainable future. Steam reforming of methane is currently the most industrially used process to produce hydrogen. One major drawback of this method is the simultaneous generation of carbon dioxide. Methane pyrolysis represents a viable alternative as the basic reaction produces no CO2 but solid carbon besides hydrogen. The aim of this study is the investigation of different molten copper alloys regarding their efficiency as catalytic media for the pyrolysis of methane in an inductively heated bubble column reactor. The conducted experiments demonstrate a strong influence of the catalyst in use on the one hand on the conversion rate of methane and on the other hand on the properties of the produced carbon. Optimization of these parameters is of crucial importance to achieve the economic competitiveness of the process.

Bulk Level Synthesis of Solid Silver Nanocatalyst: Green Mediated Approach

The synthesis of silver nano particles has acquired more attention in terms of its applicability in various fields including medicine, environmental, electronics and energy. Owing to its exceptionally good catalytic activity, this particular study is focused on the synthesis of silver nanoparticles in bulk scale, free from capping agents. Apart from the conventional colloidal green synthesis, the silver nanoparticles were synthesized in solid form using a cheap green medium lime fruit extract. The green mediated sol-gel auto combustion method eliminates the use of hazardous reducing agents and tedious purification processes. The structure, morphology and purity of the synthesized material were explored through various analytical techniques. TEM studies revealed that the synthesized silver nanoparticles were spherical in shape with average particle size of 8 nm. The potential of the silver nanoparticle as a catalyst towards reduction of organic compounds and dye degradation was established by conducting nitrophenol reduction and methylene blue degradation as a basic reaction. The nanoparticles were found to have effectively catalysed the reduction of p-nitrophenol and degradation of methylene blue with the aid of sodium borohydride as reducing agent. It may open up new path for the chemical free synthesis of crystalline silver nanoparticles with enhanced catalytic property.

锂硫电池非均相电催化剂

<p indent="0mm">With the rapid development of electronic transportation and portable electronics, commercial lithium-ion batteries would be unsatisfactory to meet the needs of future markets owing to the relatively low energy density. Seeking a reliable substitution system is becoming imperative. Lithium-sulfur (Li-S) battery has been recognized as a cutting-edge energy storage system because of its high theoretical capacity (1672 mAh g^–1) and cost-effectiveness of sulfur resources. Nevertheless, the severe shuttle effect and sluggish reaction kinetics significantly restrict its further commercialization. In the developing history of Li-S batteries, physical confinement and chemical adsorption have often been employed to achieve the anchoring of polysulfides. However, these strategies are still difficult to fully solve the problems of slow reaction kinetics and poor cycle performance. Recent years have witnessed the introduction of heterogeneous electrocatalysts into the Li-S system, which readily meets with great success in suppressing the shuttle effect and elevating the reaction kinetics. In this review, we introduce the basic reaction of Li-S battery and point out the main challenges in its current development stage, followed by summarizing the effects of electrocatalysts. Firstly, the polar electrocatalyst is able to effectively adsorb polysulfide and inhibit its diffusion in the electrolyte. Secondly, the electrocatalyst can effectively promote the conversion of polysulfide and improve the utilization rate of sulfur species. Thirdly, the uniform distribution of active sites in the electrocatalyst also contributes to the uniform deposition of short-chain polysulfides. In addition, the concepts and comparisons of homogeneous and heterogeneous electrocatalysts are presented, manifesting the essential significance of heterogeneous electrocatalysts in Li-S system. Homogeneous electrocatalysts usually refer to small soluble organic molecules with the same phase state as soluble polysulfides in the reaction system. Homogeneous electrocatalysts have more specific catalytic sites, whilst heterogeneous electrocatalysts have more diverse morphologies and higher possibility of multi-site synergistic catalysis. Then the common regulation strategies for heterogeneous electrocatalysts are classified, including vacancy regulation, doping regulation, heterostructure modulation, size control, and phase modulation. In further contexts, the underlying mechanisms of different regulation strategies for promoting polysulfide conversion are discussed. The introduction of heterogeneous electrocatalysts can effectively promote the reaction kinetics and improve their electrochemical performance. However, there are still many obstacles waiting to be solved in the practicability of Li-S batteries. For instance, there is a lack of highly selective and stable electrocatalysts. The identification of real catalytic sites in the electrocatalysts still remains unclear. Moreover, Li-S batteries have poor performance under lean electrolyte and low lithium consumption. In view of these issues, future development strategy is put forward from four aspects, encompassing material exploration, precise synthesis, characterization methods and practical application, aiming to bridge the gap between the reality and ideal in working Li-S batteries.

Extension of natural reaction orbital approach to multiconfigurational wavefunctions.

Recently, we proposed a new orbital analysis method, natural reaction orbital (NRO), which automatically extracts orbital pairs that characterize electron transfer in reaction processes by singular value decomposition of the first-order orbital response matrix to the nuclear coordinate displacements [Ebisawa et al., Phys. Chem. Chem. Phys. 24, 3532 (2022)]. NRO analysis along the intrinsic reaction coordinate (IRC) for several typical chemical reactions demonstrated that electron transfer occurs mainly in the vicinity of transition states and in regions where the energy profile along the IRC shows shoulder features, allowing the reaction mechanism to be explained in terms of electron motion. However, its application has been limited to single configuration theories such as Hartree-Fock theory and density functional theory. In this work, the concept of NRO is extended to multiconfigurational wavefunctions and formulated as the multiconfiguration NRO (MC-NRO). The MC-NRO method is applicable to various types of electronic structure theories, including multiconfigurational theory and linear response theory, and is expected to be a practical tool for extracting the essential qualitative features of a broad range of chemical reactions, including covalent bond dissociation and chemical reactions in electronically excited states. In this paper, we calculate the IRC for five basic chemical reaction processes at the level of the complete active space self-consistent field theory and discuss the phenomenon of electron transfer by performing MC-NRO analysis along each IRC. Finally, issues and future prospects of the MC-NRO method are discussed.

Methanol in the RNA world: An astrochemical perspective

The role and relevance of methanol in the origin and structure of the RNA world is discussed. Methanol is a pivotal, renewable, and regenerable source from which almost all chemical materials, simple or complex, can be accessed. Olefins and carbonyl compounds, amines and amino acids, peptides and polypeptides, and the molecular building blocks in the initial stages of the biological evolution to life’s origin are obtained through methanol as a source material by its chemical transformation. The formation of methanol, whether in stellar and interstellar media, in deep sea-bottom hot hydrothermal vents or from geothermal sources, results from CO2 hydrogenation. It is the basic reaction, setting the stage for the formation of fundamental “organic” building blocks for the formation of simple prebiotic cells to subsequent biological evolution to cells. The important observation of many organics– hydrocarbons and ions including the large expanse of methane and methanol in the interstellar medium and stellar peripheries is a clear indication of “stellar reductive processes” and ensuing reactions shedding light on the probable significant role of extraterrestrial methanol as the basic source material toward a multi-step transformation into complex life molecules such as RNA.

The Influence of Neurotrophic Factors BDNF and GDNF Overexpression on the Functional State of Mice and Their Adaptation to Audiogenic Seizures.

The high prevalence of diagnosed cases of severe neurological disorders, a significant proportion of which are epilepsy, contributes to a high level of mortality and disability in the population. Neurotrophic factors BDNF and GNDF are considered promising agents aimed at increasing the central nervous system’s adaptive potential for the development of the epileptiform activity. Despite the pronounced neuroprotective and anticonvulsant potential, an appropriate way to stimulate these endogenous signaling molecules with minimal risk of side effects remains an open question. Herein, we assessed the safety of gene therapy using original adeno-associated viral constructs carrying the genes of neurotrophic factors BDNF and GDNF in the early postnatal period of development of experimental animals. The intraventricular injection of AAV-Syn-BDNF-eGFP and AAV-Syn-GDNF-eGFP viral constructs into newborn mice was found to provide persistent overexpression of target genes in the hippocampus and cerebral cortex in vivo for four weeks after injection. The application of viral constructs has a multidirectional effect on the weight and body length characteristics of mice in the early postnatal period; however, it ensures the animals’ resistance to the development of seizure activity under audiogenic stimulation in the late postnatal period and preserves basic behavioral reactions, emotional status, as well as the mnestic and cognitive abilities of mice after simulated stress. Our results demonstrated the safety of using the AAV-Syn-BDNF-eGFP and AAV-Syn-GDNF-eGFP viral constructs in vivo, which indicates the expediency of further testing the constructs as therapeutic anticonvulsants.

ReaxFF‐based molecular dynamics simulation of the interactions between OH radicals in plasma and succinate dehydrogenase in cancer cell mitochondria

AbstractIn the plasma‐induced apoptosis of cancer cells, reactive oxygen species (ROS) cause mitochondrial enzyme dysfunction and inhibit the respiration of cancer cells. In this article, we explored the microscopic reaction mechanism between succinate dehydrogenase (SDH) and the OH radicals in plasma. The results showed that the hydrogen abstraction reaction was the most basic reaction mode. The S–H bond had the highest reaction activity, and the cysteine had the highest reaction participation rate in the simulation. Increasing OH radical concentration, the damage degree of SDH increased, while the utilization rate of OH decreased. This study facilitates a new perspective of the apoptosis mechanism of cancer cells in plasma therapy and provides a reference for the clinical plasma treatment of cancer.

Influence mechanism of inert carrier on the anti-carbon deposition effect of nickel-based oxygen carrier in chemical looping methane reforming process

In this paper, density functional theory (DFT) calculations are applied to investigate the reaction mechanism of syngas production by chemical looping reforming of methane on NiO-based surfaces. The work mainly focused on the basic reaction steps, including the catalytic dehydrogenation of CH4, the generation of H2 and H2O, and the formation of CO. The mechanism of formation and removal of carbon deposits is analyzed emphatically. Firstly, it is found that NiO fragments are very stably attached on the surface of ZrO2 and Al2O3 and carriers. For the methane dehydrogenation step, it is shown that CH4 → CH3 + H is the rate-limiting step on both surfaces. Moreover, the calculation results showed that the formation of CO and H2O molecules was also more favorable on the surface of NiO/Al2O3, indicating that the Al-Ni structure owns better lattice oxygen transferring ability. For the key step of the H2 molecule generation, the surface of NiO/ZrO2 shows better reaction performance and lower activation energy. The NiO fragments loaded on the surface of Al2O3 is able to exhibit better anti-carbon properties, indicating that the introduction of Al2O3 can well enhance the cyclic stability of oxygen carriers.

The performance and applications of lignin based hydrogels: a review

Lignin is the only natural aromatic polymer and the second most abundant lignocellulosic resource in nature after cellulose, and its derived high-value products can be used in a variety of fields. An efficient, highly value-added and high-quality production of lignin is critical for lignocellulose biorefinery, but the complex and variable structure of lignin macromolecules, poor activity of reactions, and redundant functional groups make it difficult to prepare polymeric materials with stable properties. With the increasing research on lignin modification, the application of lignin composite hydrogels has also received great attention. In this paper, the preparation of lignin composite hydrogels based on the basic structural composition and reaction properties of lignin was briefly outlined. The current applications of lignin composite hydrogels, including biosensors, controlled release materials, environmentally responsive materials, adsorbent materials, electrode materials, and other materials, were summarized. Moreover, future perspectives of lignin-based composite hydrogels were prospected.

Effect of side reactions in hybrid distillation system: Parallel production of ethyl acetate and glycols

A hybrid distillation process for pure ethyl acetate production was studied in the presented work. Ethyl acetate was produced via direct esterification of ethanol by acetic acid in a reactive distillation (RD) column with parallel production of glycols. Ethylene oxide hydration was considered as an auxiliary reaction to consume the esterification by-product – water. Thus, high level of process integration and intensification was achieved in the complex reactive system applying chemical reaction synergy. However, possible undesired side reactions should be considered in such complex reactive systems. In this work, three different reactive distillation column models assuming non-equilibrium (rate-based) stage approach were built to calculate the effect of side reactions. First case study assumed only basic reactions (main esterification and hydration); in the second case study, eight reactions were taken into account, and the last case study assumed splitting EO feed to achieve higher purity of product streams. Side reactions affect the process design significantly. To obtain the required products in sufficient purity, optimization of the RD column was performed using two different methods: conventional SQP algorithm, and genetic algorithm. Optimization results show that the conventional SQP algorithm can solve simple problems finding suitable solutions that meet the design requirements. This method failed when optimizing a complex reactive system. The genetic algorithm improved the solution found by the SQP method and the obtained results showed that parallel production of pure ethyl acetate and glycols in one reactive distillation column is a promising way to intensify the production process. Process modeling was performed using the Aspen Plus software and MATLAB.

OIDIPOUS TYRANNOS’TA KEHANET VE MERHAMET

This article focuses on the place and importance of pity in Sophocles’ Oedipus Tyrannus. Although the feeling of pity or compassion is just the basic emotional reaction expected from the audience, it is the most important element that takes place in the center of the plot of Oedipus Tyrannus and determines the course of events in the tragedy. Sophocles made some important changes about the Oedipus myth in the tragedy of Oedipus Tyrannus and reconstructed the plot of the tragedy in an original way. Our main claim here is this: The main character's pity is the basis of the critical changes Sophocles made in the myth. For just as the feeling of pity was decisive when Laios’ slave did not leave the baby Oedipus on the mountain, but gave it to the Corinthian messenger to raise him, there is also the intense fear and pity behind Oedipus’ important decisions that led him to investigate the cause of the great plague epidemic in the city of Thebes and left the administration to Creon.