Formation Of Products Research Articles

The Expression of Genes CYP1A1, CYP1B1, and CYP2J3 in Distinct Regions of the Heart and Its Possible Contribution to the Development of Hypertension.

It is believed that alterations in the functioning of the cytochrome P450 (CYP), which participates in metabolic transformations of endogenous polyunsaturated fatty acids (PUFAs) (with the formation of cardioprotective or cardiotoxic products), affects the development of age-related cardiovascular diseases and reduces the effectiveness of some cardioselective drugs. For example, CYP2J2 activation or CYP1B1 inhibition protects against the cardiovascular toxicity of anticancer drugs. It is currently unclear whether CYPs capable of metabolizing arachidonic acid and ω-3 PUFAs to vasodilatory and vasoconstrictive derivatives are expressed in all heart regions. The work was performed on senescence-accelerated OXYS rats featuring elevated blood pressure, OXYSb rats (an OXYS substrain with normal blood pressure), and Wistar rats as a "healthy" control. The mRNA level was determined in the right and left ventricles, the right and left atria, and the aorta of 1-, 3-, and 12-month-old rats. We showed that all heart regions express CYPs capable of metabolizing arachidonic acid and ω-3 PUFAs and revealed significant differences between heart regions both in the mRNA level of genes CYP1B1, CYP2J3, and CYP1A1 and in the time course of expression changes with age. We noticed that expression levels of these CYPs in the heart regions and aorta differ between hypertensive OXYS rats, normotensive OXYSb rats, and healthy Wistar rats but could not detect any clear-cut patterns associated with the hypertensive status of OXYS rats.

Advances in Research on the Improvement of Low-Salt Meat Product Through Ultrasound Technology: Quality, Myofibrillar Proteins, and Gelation Properties.

The high sodium content in meat products poses health risks to consumers and does not align with modern green and healthy living standards. Current strategies for directly reducing the sodium content in meat products are limited by their negative impact on the sensory or quality attributes of the products. In recent years, there has been great interest in applying ultrasound technology to reduce sodium content. This paper discusses the advantages and disadvantages of current mainstream strategies for reducing the sodium content in meat products, as well as the potential mechanisms by which ultrasound-assisted marination improves the quality of low-salt meat products. The main findings indicate that ultrasound, through its cavitation and mechanical effects, facilitates the transition of proteins from stable insoluble aggregates to stable soluble complexes, exposing more hydrophilic groups and, thus, enhancing protein solubility. At the same time, ultrasound promotes a greater number of proteins to participate in the formation of interfacial layers, thereby increasing emulsifying activity. Furthermore, ultrasound treatment promotes the interaction between proteins and water, leading to partial unfolding of protein chains, which allows polar residues to more readily capture water in the gel, thereby improving the water-holding capacity of the gel. These effects will contribute to the formation of high-quality low-salt meat products. However, variations in the frequency, intensity, and duration of ultrasound treatment can lead to differing effects on the quality improvement of low-salt meat products.

Porous N-Doped Carbon-encapsulated Iron as Novel Catalyst Architecture for the Electrocatalytic Hydrogenation of Benzaldehyde.

Carbon porous materials containing nitrogen functionalities and encapsulated iron-based active sites have been suggested as electrocatalysts for energy conversion, however their applications to the hydrogenation of organic substrates via electrocatalytic hydrogenation (ECH) remain unexplored. Herein, we report on a Fe@C:N material synthesized with an adapted annealing procedure and tested as electrocatalyst for the hydrogenation of benzaldehyde. Using different concentrations of the organic, and electrolysis coupled to gas chromatography experiments, we demonstrate that it is possible to use such architectures for the ECH of unsaturated organics. Potential control experiments show that ECH faradaic efficiencies >70 % are possible in acid electrolytes, while maintaining selectivity for the alcohol over the pinacol dimerization product. Estimates of product formation rates and turnover frequency (TOF) values suggest that these carbon-encapsulated architectures can achieve competitive performance in acid electrolytes relative to both base and precious metal electrodes.

Abiotic Acyl Transfer Cascades Driven by Aminoacyl Phosphate Esters and Self-Assembly.

Biochemical acyl transfer cascades, such as those initiated by the adenylation of carboxylic acids, are central to various biological processes, including protein synthesis and fatty acid metabolism. Designing cascade reactions in aqueous media remains challenging due to the need to control multiple, sequential reactions in a single pot and manage the stability of reactive intermediates. Herein, we developed abiotic cascades using aminoacyl phosphate esters, the synthetic counterparts of biological aminoacyl adenylates, to drive sequential chemical reactions and self-assembly in a single pot. We demonstrated that the structural elements of amino acid side chains (aromatic versus aliphatic) significantly influence the reactivity and half-lives of aminoacyl phosphate esters, ranging from hours to days. This behavior, in turn, affects the number of couplings we can achieve in the network and the self-assembly propensity of activated intermediate structures. The cascades are constructed using bifunctional peptide substrates featuring side chain nucleophiles. Specifically, aromatic amino acids facilitate the formation of transient thioesters, which preorganized into spherical aggregates and further couple into chimeric assemblies composed of esters and thioesters. In contrast, aliphatic amino acids, which lack the ability to form such structures, predominantly undergo hydrolysis, bypassing further transformations after thioester formation. Additionally, in mixtures containing multiple aminoacyl phosphate esters and peptide substrates, we achieved selective product formation by following a distinct pathway that favors subsequent reactions through reactivity changes and self-assembly. By coupling chemical reactions with molecules of varying reactivity time scales, we can drive multiple reaction clocks with distinct lifetimes and self-assembly dynamics, facilitating precise temporal and structural regulation.

Reducing Stoichiometric Excess of Base to Catalytic Amount: Revisiting Staudinger Reaction for -lactam Synthesis

Background: -lactams have been primarily utilized as a leading class of effective antibiotics. They have been found to show activity against various diseases, prompting the scientific community to prioritise innovative protocols for their synthesis. The general and well-known synthetic strategy involves the classical Staudinger reaction exhibiting [2+2] cycloaddition reaction. However, the protocol utilizes stoichiometric excess of base for efficient product formation. Objective: A smarter and more acceptable approach for the synthesis of -lactams would be to reduce the excess base to a catalytic amount, furnishing a catalytic version of the Staudinger reaction. The modified version can eliminate the hazards arising out of excess use of the base, ultimately promoting the environmentally benign approach. Methods: With this hypothesis, a base-catalyzed approach in dimethyl formamide (DMF) towards the synthesis of -lactam via Staudinger reaction has been endorsed under moderate reaction conditions. Results: The scope of the substrates was explored with both electron-withdrawing and electronreleasing substitutions in the formation of -lactam. The reduction of the base amount from stoichiometric to catalytic amount was justified by the involvement of DMF in generating the basic condition for the reaction. Conclusion: It was hypothesized that the decomposition of DMF under the base-catalysed reaction condition can generate dimethylamine, which produces the required basic environment. conclusion: A base-catalysed approach in dimethyl formamide (DMF) towards the synthesis of β-lactam via Staudinger reaction has been endorsed under moderate reaction conditions. The substrates scope was explored with both electron withdrawing and electron releasing substitutions in the formation of β-lactam. The reduction of base amount from stoichiometric to catalytic was justified by the involvement of DMF in generating the basic condition for the reaction. It was hypothesized that the decomposition of DMF under the base catalysed reaction condition can generate dimethylamine which produces the required basic environment.

Assessing the combination of graphene and graphene oxide nanosheets in cement-based materials

Graphene (Gr) and Graphene Oxide (GO) are graphene-based nanosheet (GNS) materials with ultrahigh mechanical properties. The addition of Gr/GO (from 0.01 % to 2 % in mass) to a cement-based material can significantly enhance its mechanical properties. GO has higher efficiency than Gr, but it is more costly. In this paper, a Gr-GO solution was developed by combining Gr and GO in water. The compressive strengths of the samples with and without Gr-GO were determined. Deep analyses were performed by applying several imaging techniques such as nano-tomography, SEM, and confocal Raman imaging to exploit the correlation between microstructural properties and mechanical properties and durability of cement-based materials. The microstructural properties were also quantified from the 3D images obtained by nano-tomography. The results showed that the GNS-added sample had a higher porosity (about 12.4 %) than that of the reference sample (about 6.1 %) but the GNS-added sample had a more homogeneous distribution of micropores. Raman imaging results explained the formation of hydration product and acceleration of hydration rate by Gr-GO in GNS-added samples. The mechanical properties showed that the addition of 0.03 % Gr-GO could increase the compressive strength of mortar samples by 28 %.

How Do ROS Induce NETosis? Oxidative DNA Damage, DNA Repair, and Chromatin Decondensation.

Neutrophil extracellular traps (NETs) are intricate, DNA-based, web-like structures adorned with cytotoxic proteins. They play a crucial role in antimicrobial defense but are also implicated in autoimmune diseases and tissue injury. The process of NET formation, known as NETosis, is a regulated cell death mechanism that involves the release of these structures and is unique to neutrophils. NETosis is heavily dependent on the production of reactive oxygen species (ROS), which can be generated either through NADPH oxidase (NOX) or mitochondrial pathways, leading to NOX-dependent or NOX-independent NETosis, respectively. Recent research has revealed an intricate interplay between ROS production, DNA repair, and NET formation in different contexts. UV radiation can trigger a combined process of NETosis and apoptosis, known as apoNETosis, driven by mitochondrial ROS and DNA repair. Similarly, in calcium ionophore-induced NETosis, both ROS and DNA repair are key components, but only play a partial role. In the case of bacterial infections, the early stages of DNA repair are pivotal. Interestingly, in serum-free conditions, spontaneous NETosis occurs through NOX-derived ROS, with early-stage DNA repair inhibition halting the process, while late-stage inhibition increases it. The intricate balance between DNA repair processes and ROS production appears to be a critical factor in regulating NET formation, with different pathways being activated depending on the nature of the stimulus. These findings not only deepen our understanding of the mechanisms behind NETosis but also suggest potential therapeutic targets for conditions where NETs contribute to disease pathology.

Sustainable and Advanced LED-Implanted Microfluidic Photoreactor with Coupled Optical Fiber Enabling Efficient Photocatalytic Synthesis Beside Online Reaction Progress Monitoring.

The conventional methods for the photoinduced synthesis of benzimidazoles may need further improvement regarding a safer and energy-efficient synthesis platform with in-process monitoring for maximum yield within a much reduced reaction time. This work describes the use of a novel optofluidic Lab-on-a-Chip technology for safer, energy-efficient, and expedited synthesis of benzimidazole derivatives in excellent yields along with real-time quantitative measurement during product formation. This innovative method involves synthesis within LED-embedded microfluidic reactors, allowing for rapid synthesis of benzimidazole derivatives via photoinduced condensation cyclization reactions of aryl aldehydes and o-phenylenediamines using a Rose Bengal/fluorescein photocatalyst. It results in good to excellent yields (85-94%) in a notably shorter period of time (10 min) as compared to that for the batch protocol reaction (2-3 h). The incorporation of a reaction-monitoring microfluidic device precisely connected to the microfluidic reactor (microreactor) unit successfully avoids interference from light sources, ensuring consistent UV-vis spectroscopic observations of the produced benzimidazole derivatives. This LED-embedded microfluidic device's capability of photoinduced synthesis, along with real-time spectroscopic analysis, represents a promising breakthrough in organic synthesis. The proposed approach minimizes the potential for accidents, prevents waste of chemicals, maximizes atom economy, and designs an energy-efficient synthesis route, along with real-time in-process monitoring.

Hydrodeoxygenation of Glycerol to Propene Over Molybdenum and Niobium Phosphate Catalysts

AbstractIn single‐step conversion of glycerol to propene, the intricate catalytic pathways with molybdenum and niobium catalysts remain elusive. While these catalysts can effectively accelerate the hydrogenolytic cleavage of the glycerol CO bonds, resulting in a high selectivity to propene, the routes have not been thoroughly studied. This study explores the reaction routes and the role hydrogen plays in determining the product distribution. The hydrodeoxygenation (HDO) of glycerol was investigated using various glycerol purities in both batch and continuous reaction modes. Remarkably, Mo(PO4)x and Nb(PO4)x demonstrated catalytic performance with raw glycerol, indicating that impurities had no detrimental effect on the catalyst's activity. In batch mode, a propene selectivity of 53% was achieved over Mo(PO4)x as the catalyst, highlighting the catalyst's stability under these conditions. In continuous operation, the highest product selectivity to propene (12%) was observed at low temperatures (573 K), while more C2 to C6 alkanes were formed at increased temperatures (623 and 673 K). Whereas a hydrogen atmosphere promotes formation of 2‐propenol, as primary precursor to propene, an inert atmosphere leads to increased formation of propanal and dissociation products. Our work has elucidated new routes to upcycle biorenewable glycerol to propene over Mo(PO4)x and Nb(PO4)x catalysts.

Exploring Electrocatalytic CO2 Reduction Over Materials Derived from Cu‐Based Metal‐Organic Frameworks

AbstractThe direct valorization of carbon dioxide (CO2) into value‐added chemicals offers an efficient and attractive approach to promoting carbon neutrality. Among the available methods, the electrocatalytic CO2 reduction reaction (eCO2RR) for producing multicarbon products (C2+) is gaining attention owing to its simplicity. However, achieving selective control over product formation remains a challenge. One key issue is the lack of a reliable correlation between the physicochemical properties of electrocatalytic materials and their activity and selectivity. To address this gap, we conducted a model study in which carbonized CuxZny@C materials, derived from metal‐organic frameworks (MOFs), were synthesized with varying Cu/Zn ratios. The pyrolyzed bimetallic MOFs retained key properties of the original MOFs while also developing new characteristics. These subtle changes in physicochemical properties influenced product selectivity. The findings of our study revealed that higher Zn doping favors the formation of single‐carbon (C1) products, whereas it is less favorable for multicarbon (C2+) products. Optimizing the Cu/Zn ratio was emphasized through characterization techniques, which will help guide the design of improved electrocatalytic systems for the eCO2RR process.

Detection of virulence factors and antimicrobial susceptibility pattern of clinically significant Klebsiella pneumoniae isolates in a tertiary care hospital

Introduction: Klebsiella pneumoniae is associated with a variety of infections across all age groups, both in community and hospital settings. Many strains of K. pneumoniae produce virulence factors such as a capsule, siderophores, biofilm, and hypermucoviscosity, which facilitate adhesion, invasion, and colonization. Additionally, the rising antibiotic resistance in K. pneumoniae strains poses a significant challenge, limiting treatment options. This study aims to identify the virulence factors and assess the antimicrobial susceptibility of clinically significant K. pneumoniae isolates. Materials and Methods: K. pneumoniae isolates were obtained from urine, sputum, blood, cerebrospinal fluid, pus swabs/aspirates, and tissue samples. Standard biochemical tests were performed for identification. Capsule formation, hypermucoviscosity, siderophore production, and biofilm formation were detected phenotypically. Antibiotic susceptibility testing was carried out using the disk diffusion method, and primary and confirmatory tests were conducted for extended-spectrum beta-lactamases (ESBL) and carbapenemase production. Results: Capsule formation, hypermucoviscosity, siderophore production, and biofilm formation were detected in 100%, 15%, 40%, and 15% of the isolates, respectively. Of the isolates, 40% were multidrug-resistant, 55% produced ESBL, 8% expressed AmpC beta-lactamase, and 10% produced carbapenemase. Conclusion: Capsule formation was the most prevalent virulence factor, followed by siderophore production. The majority of K. pneumoniae isolates demonstrated susceptibility to amikacin, piperacillin-tazobactam, and carbapenems. However, 40% of the isolates were multidrug-resistant, with ESBL production being the most common resistance mechanism.

Valorization of olive mill wastewater as a process medium in co-hydrothermal carbonization with Sicilian agro-wastes: effects of interaction on product yield and properties

This work explores the valorization of residual olive mill wastewater as a process aqueous medium for co-hydrothermal carbonization (co-HTC) of typical Sicilian agro-wastes (tangerine and orange peel wastes). Co-HTC experiments were carried out at 180 and 220 °C to assess the interaction between the feedstocks. Synergistic effects increased the yield of hydrochar and gas phases while antagonism altered the formation of aqueous products. Compared to the expected value, hydrochar yield was increased by 37 wt%, on average, while the interaction effect on gas phase was weaker (+23 wt%, on average) and increased with temperature. Both the retention of unhydrolyzed primary char and the recapture of secondary char phases from process water enhanced the hydrochar recovery in different ways according to feedstock nature and co-HTC conditions. On the basis of hydrochars characterization through elemental analysis and surface functionality, the degree of carbonization was significantly improved after co-HTC due to promoted dehydration and decarboxylation reactions. As result, co-hydrochars exhibited a moderately higher energy content and a greater thermal stability compared to samples obtained from HTC of individual substrates. Co-hydrochars also retained relatively high amounts of nutrients such as phosphorus, potassium and calcium, which could enable their use as soil improvers.

NHC-Catalyzed Aldimine Umpolung/6π-Electrocyclization Cascade to Access Tetracyclic Dihydrochromeno Indoles.

The umpolung of aldimines using N-heterocyclic carbenes (NHCs) is less explored compared to the established polarity reversal of aldehydes. Described herein is an NHC-catalyzed imine umpolung /6π-electrocyclization cascade, which leads to the atom- and pot-economic synthesis of biologically important dihydrochromeno indoles. For the first time, the nucleophilic aza-Breslow intermediates have been intercepted with unactivated alkynes. Preliminary mechanistic and DFT studies shed light on the role of the phenolic -OH moiety in promoting the addition of the aza-Breslow intermediate to the unactivated alkyne via an intramolecular proton transfer in a stepwise manner. DFT studies also support the regioselectivity preference for the 5-exo-dig cyclization pathway, leading to the exclusive formation of the indole products. Moreover, a comparison of Gibbs free energies provides insight into a thermodynamically preferred 6π-electrocyclization over a competing oxa-Michael pathway. Further, this strategy is applied to the formal synthesis of a Hepatitis C Virus (HCV) NS5A inhibitor in a step-economical method.

NHC‐Catalyzed Aldimine Umpolung/6π‐Electrocyclization Cascade to Access Tetracyclic Dihydrochromeno Indoles

The umpolung of aldimines using N‐heterocyclic carbenes (NHCs) is less explored compared to the established polarity reversal of aldehydes. Described herein is an NHC‐catalyzed imine umpolung /6π‐electrocyclization cascade, which leads to the atom‐ and pot‐economic synthesis of biologically important dihydrochromeno indoles. For the first time, the nucleophilic aza‐Breslow intermediates have been intercepted with unactivated alkynes. Preliminary mechanistic and DFT studies shed light on the role of the phenolic ‐OH moiety in promoting the addition of the aza‐Breslow intermediate to the unactivated alkyne via an intramolecular proton transfer in a stepwise manner. DFT studies also support the regioselectivity preference for the 5‐exo‐dig cyclization pathway, leading to the exclusive formation of the indole products. Moreover, a comparison of Gibbs free energies provides insight into a thermodynamically preferred 6π‐electrocyclization over a competing oxa‐Michael pathway. Further, this strategy is applied to the formal synthesis of a Hepatitis C Virus (HCV) NS5A inhibitor in a step‐economical method.

Enhanced photoelectrochemical CO2 reduction activity towards selective generation of alcohols over CuxO/SrTiO3 heterojunction photocathodes

Photoelectrochemical reduction (PECR) of CO2 to value-added chemicals and fuels will reduce the dependency on fossil fuels, also it will solve environmental issues that arise due to greenhouse gases. A heterojunction of CuxO/SrTiO3 with varying post-annealing temperature ranges from 300 to 600 °C (CS300-600) was synthesized by overlying the spin-coated SrTiO3 on electrodeposited Cu2O over the FTO glass substrate. The synthesized photoelectrode's crystallinity and phase formation significantly varied by varying the post-annealing temperature, which was characterized via XRD and Raman spectroscopy. Optical, morphological, type of heterojunction formation and elemental surface oxidation states of photoelectrodes were studied through UV–visible DRS spectrum, FE-SEM, and XPS analysis respectively. Electrocatalytic analysis such as Linear Sweep Voltammetry (LSV), and Electrochemical Impedance Spectrometry (EIS) was employed, thus it conforms to the highest photocurrent density (−1.38 mA/cm2 at −0.6V vs. Ag/AgCl), and low charge transfer resistance (RCT=0.412 kΩ) at the electrode-electrolyte interfaces for CS500 photoelectrode as compared to others photoelectrodes. PECR of CO2 to liquid product formation was evaluated by applying different potential ranges (0 to −0.6 V vs. Ag/AgCl). Highest methanol formation of 48.69 μmol.cm−2hr−1, which is approximately 9 times enhanced as compared to the pure Cu2O (5.62 μmol.cm−2hr−1) photoelectrode at 0 V vs Ag/AgCl for CS500 heterojunction. Optimization of overlaying SrTiO3 synthesis temperature for crystallization formation on Cu2O and applied photoelectrode potential findings could pave the way for designing other new heterojunction types for selective liquid alcohol production.

Red Mud as a Potential Catalyst for Petrochemicals Production from Oxygenated Aromatic Plastic Wastes via Fast Pyrolysis

The increased rate of post‐use accumulation of the heteroatom‐containing plastic wastes like polyethylene terephthalate (PET), polycarbonate (PC) and polyurethane (PU) in the environment propels the research for effective and sustainable valorization. In this study, PET from bottle waste, PC from compact discs and PU from waste wind turbine blade were characterized and employed for fast pyrolysis experiments. Importantly, red mud (RM), a mixed oxide, rich in Fe, Al, Si, Na and Ca, was used as a catalyst for fast pyrolysis. The effects of temperature and feed‐to‐catalyst ratio on product yields were studied to elucidate the product formation mechanism. Benzoic acid and its derivatives, bisphenol‐A and oxygenated aromatics, and 4,4’‐methylenebisbenzamine were the major products obtained from the non‐catalytic fast pyrolysis of PET, PC and PU, respectively. The use of RM improved the yield of aromatic hydrocarbons from PET to 27.8 wt.% at 550°C, phenolics from PC to 46.6 wt.% at 550°C, and 4,4’‐methylenebisbenzamine to 34.9 wt.% at 650oC. The catalytic activity of RM is ascribed to the presence of active basic sites. The present study paves the path for the catalytic upcycling of challenging plastic wastes using industrial waste like RM as a sustainable catalyst from a circular economy viewpoint.

Mild water deficit at seed filling stage promotes drought-tolerant soybean production formation and flavonoids accumulation

Soybean is an important crop for both grain and oil use. Appropriate agricultural managements increase crop productivity quantity and chemical nutrition quality. This study utilized two soybean varieties HN44(drought-tolerant) and SN14 (drought-sensitive)to analyze mechanism effect of light drought stress on instantaneous water use efficiency(WUEi), yield and isoflavone content by changes in the transcriptome and metabolome during the early seed-filling stage. The results showed that light drought stress can improve WUEi, stimulate the yield potential and increase the content of Daidzin and 6''-O-malonyldaidzin of HN44. In addition, under light drought stress, the differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) in HN44 and SN14 were significantly enriched in the biosynthetic pathways of flavonoids and isoflavones. The flavonoid metabolites in HN44 increased, while those in SN14 decreased. Through the different expression patterns of DEGs and DAMs in the two varieties, differential genes and differential metabolites were screened out, such as CHS, HCT, F3H, HIDH, IF7GT, VR, p-coumaroylquinic, and 6''-O-Malonylglycitin. These genes and metabolites can provide theoretical basis for the selection breeding of drought-tolerant soybean varieties and the evaluation of drought-resistant resources. The findings provided important agronomic strategies for improving the yield, bioactive substances, and water resource management of crop soybeans.

Interaction between marine and terrestrial biogenic volatile organic compounds: Non-linear effect on secondary organic aerosol formation

Biogenic volatile organic compounds (BVOCs) are the largest source of secondary organic aerosols (SOA) globally. However, the complex interactions between marine and terrestrial BVOCs remain unclear, inhibiting our in-depth understanding of the SOA formation in the coastal areas and its environmental impacts. Here, we performed smog chamber experiments with mixed α-pinene (a typical monoterpene) and dimethyl sulfide (DMS, a typical marine emission BVOC) to investigate their possible interactions and subsequent SOA formation. It is found that DMS has a non-linear effect on SOA generation: The mass concentration and yield of SOA show increasing and then decreasing trends with the increase of the initial concentration of DMS. The increasing trend can be attributed to OH regeneration from isomerization of the CH3SCH2OO radical together with acid-catalyzed heterogeneous reactions by the oxidation of DMS, while the decreasing trend is explained by the less contribution of isomerization reaction and the high OH reactivity that inhibits the formation of low volatility products. The results from infrared spectra and mass spectra together reveal the contribution of sulfur-containing molecules in the mixed system. Moreover, the mass spectra results indicate that acidic products generated by DMS photooxidation enhance the O:C ratio, while organosulfates are produced to contribute to the formation of mixed SOA. In addition, the trends in relative abundance of highly oxygenated organic molecules (HOMs) with C8 - C10 multiple functional groups in different mixed systems agree well with the turning point of the SOA yield. The findings of this study have significant implications for understanding binary or more complex systems in the atmosphere in the coastal areas.

Reduction of carbon dioxide to methane and ethanol on the surface of graphyne-like boron nitride (BNyen) monolayer: A DFT study

Recently, scientists have created a novel type of boron nitride material known as BNyen. This material is similar in structure to Graphyne and has a higher N:B ratio than traditional boron nitride due to the addition of boron and nitrogen connecting segments within its units. This material has been studied for its potential as a photocatalyst for reduction of CO2 using DFT approaches. Optical and electronic attributes of BNyen suggest that it has a wider visible-light range and a band gap of 5.69 eV. By adding boron to BNyen, patial distributions of LUMO and HOMO indicate that π network has been extended, resulting in significantly greater photocatalytic efficiency. Upon the adsorption of CO2 on BNyen monolayer, the band gap significantly decreases, indicating a strong interaction between the BNyen and CO2. DFT computations were employed to explore the mechanism of CO2 reduction to a single carbon product catalyzed by BNyen. Based on the ΔG values, the optimized pathway for this reduction is from CO2 to CH4. Additionally, the potential formation of di-carbon products was considered, and based on the free energy values, CH3CH2OH is identified as the final di-carbon product. The Gibbs free energies for potential CO2 reaction pathways on BNyen were calculated, revealing that CO2 can be reduced to CH4 with a low limiting potential of −0.37 V and to CH3CH2OH with a low limiting potential of −0.57 V, both processes being powered by solar energy. In CO2RR, the competing hydrogen evolution reaction (HER) must be considered. The free energy of HER (ΔG = 0.96 eV) is significantly higher than the ΔG of the rate-determining steps for the mono-carbon product (0.37 eV) and the di-carbon product (0.57 eV) on BNyen. Therefore, BNyen effectively suppresses HER during the CO2RR process. This research can serve as a valuable guide for developing novel types of BNyen as appropriate photocatalysts for CO2 reduction reactions (CO2RR).

Features of the formation of tourism product in Mongolia

Mongolia is a unique tourist destination that attracts travelers with its culture, natural landscapes and historical heritage. The article examines the features of the formation of the tourism product in Mongolia, including key aspects that contribute to the successful development of tourism in this country.