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Methanol steam reforming (MSR) is an attractive route for producing clean energy hydrogen. PdZn alloys are extensively studied as potential MSR catalysts for their stability and high CO2 selectivity. Here, we investigated the reaction mechanism using density functional calculations, mean-field microkinetic modeling (MF-MKM), and kinetic Monte Carlo (kMC) simulations. To overcome the over-underestimation of CO2 selectivity by log-kMC, an ads-kMC algorithm is proposed in which the adsorption/desorption rate constants were reduced under certain requirements and the diffusion process was treated by redistributing surface species each time an event occurred. The simulations show that the dominant pathway to CO2 at low temperatures is CH3OH → CH3O → CH2O → H2COOH → H2COO → HCOO → CO2. The ads-kMC predicted OH coverage is 2–3 times that of MF-MKM, while they produce similar coverage for other species. Analyses indicate that surface OH promotes the dehydrogenation of CH3OH, CH3O, and H2COOH significantly and plays a key role in the MSR process. The dissociation of water/methanol is the most important rate-limiting/rate-inhibiting step. The CO2 selectivity obtained by the two methods is close to each other and consistent with the experimental trend with temperature. Generally, the ads-kMC results agree with the MF-MKM ones, supporting the previous finding that kMC and MF-MKM predict similar results if the diffusion is very fast and adsorbate interactions are neglected. The present study sheds light on the MSR process on PdZn alloys, and the proposed scheme to overcome the stiff problems in kMC simulations is worthy of being extended to other systems. [ABSTRACT FROM AUTHOR]

Some of the authors of the present research group have previously reported mass spectrometric detection of [PdAu9(PPh3)8(CN)]2+ (PdAu9CN) by atmospheric pressure plasma (APP) irradiation of [MAu8(PPh3)8]2+ (PdAu8) in methanol and proposed based on density functional theory (DFT) calculations that PdAu9CN is constructed by inserting a CNAu or NCAu unit into the Au–PPh3 bond of PdAu8 [Emori et al., J. Chem. Phys. 155, 124312 (2021)]. In this follow-up study, we revisited the structure of PdAu9CN by high-resolution ion mobility spectrometry on an isolated sample of PdAu9CN with the help of dispersion-corrected DFT calculation. In contradiction to the previous proposal, we conclude that isomers in which an AuCN unit is directly bonded to the central Pd atom of PdAu8 are better candidates. This assignment was supported by Fourier transform infrared and ultraviolet–visible spectroscopies of isolated PdAu9CN. The simultaneous formation of [Au(PPh3)2]+ and PdAu9CN suggests that the AuCN species are formed by APP irradiation at the expense of a portion of PdAu8. These results indicate that APP may offer a unique method for transforming metal clusters into novel ones by generating in situ active species that were not originally added to the solution. [ABSTRACT FROM AUTHOR]

The direct conversion of methane to methanol has attracted increasing interest due to abundant and low-cost natural gas resources. Herein, by anchoring Cr-oxo/-oxyhydroxides on UiO-66 metal–organic frameworks, we demonstrate that reactive anionic oxyl radicals can be formed by controlling the coordination environment based on the results of density functional theory calculations. The anionic oxyl radicals produced at the completely oxidized CrVI site acted as the active species for facile methane activation. The thermodynamically stable CrVI-oxo/-oxyhydroxides with the anionic oxyl radicals catalyze the activation of the methane C–H bond through a homolytic mechanism. An analysis of the results showed that the catalytic performance of the active oxyl species correlates with the reaction energy of methane activation and H adsorption energies. Following methanol formation, N2O can regenerate the active sites on the most stable CrVI oxyhydroxides, i.e., the Cr(O)4Hf species. The present study demonstrated that the anionic oxyl radicals formed on the anchored CrVI oxyhydroxides by tuning the coordination environment enabled facile methane activation and facilitated methanol production. [ABSTRACT FROM AUTHOR]

The abundance of extraterrestrial methanol makes the reaction between methanol molecules in a molecular cluster a possible key step in the search for mechanisms for the formation of more complex molecules under the conditions of the interstellar medium as well as circumstellar and planetary atmospheres. The reaction leading to the formation of the dimethyl ether ion from a methanol molecule interacting with a protonated methanol ion via the elimination of a water molecule is a basic mechanism for the formation of complex organic molecules. Here, we experimentally examine such reactions in the gas phase, analyzing the production and reactivity of protonated cluster ions formed by the ionization of a supersonic jet of methanol. Focusing especially on the post-collisional relaxation of the protonated methanol dimer and trimer ions after high-energy single collisions, the results indicate a strong size selectivity favoring the occurrence of this reaction only in the dimer ion. To elucidate this behavior, the velocity distribution of the eliminated water molecule was measured using an event-by-event coincidence analysis. These results are interpreted using quantum chemical calculations of the dissociation pathways. It turns out that in the dimer case, two transition states are able to contribute to this intracluster reaction. In the trimer case, methanol evaporation appears as the most energetically favorable relaxation pathway. [ABSTRACT FROM AUTHOR]

Photocatalytic utilization of methanol and nitrate as carbon and nitrogen sources for the direct synthesis of amino acids could provide a sustainable way for the valorization of green "liquid sunlight" and nitrate waste. In this study, we develop an efficient photochemical method to synthesize glycine directly from methanol and nitrate, which cascades the C−C coupling to form glycol, nitrate reduction to NH3, and finally C−N coupling to generate glycine. Interestingly, the involved photocatalytic tandem reactions show a synergistic effect, in which the presence of nitrate is the dominant factor to enable the overall reaction and reach high synthetic efficiency. Ba2+−TiO2 nanoparticles are confirmed as a feasible and efficient catalyst system for the photosynthesis of glycine with a remarkable glycine photosynthesis rate of 870 μmol gcat−1 h−1 under optimal conditions. This work establishes a novel catalytic system for amino acid synthesis from methanol and nitrate under mild conditions. These results also allow us to further suppose the formation pathways of amino acids on the primitive earth, as an extension to proposals based on the Miller‐Urey experiments. [ABSTRACT FROM AUTHOR]

Photocatalytic utilization of methanol and nitrate as carbon and nitrogen sources for the direct synthesis of amino acids could provide a sustainable way for the valorization of green "liquid sunlight" and nitrate waste. In this study, we develop an efficient photochemical method to synthesize glycine directly from methanol and nitrate, which cascades the C−C coupling to form glycol, nitrate reduction to NH3, and finally C−N coupling to generate glycine. Interestingly, the involved photocatalytic tandem reactions show a synergistic effect, in which the presence of nitrate is the dominant factor to enable the overall reaction and reach high synthetic efficiency. Ba2+−TiO2 nanoparticles are confirmed as a feasible and efficient catalyst system for the photosynthesis of glycine with a remarkable glycine photosynthesis rate of 870 μmol gcat−1 h−1 under optimal conditions. This work establishes a novel catalytic system for amino acid synthesis from methanol and nitrate under mild conditions. These results also allow us to further suppose the formation pathways of amino acids on the primitive earth, as an extension to proposals based on the Miller‐Urey experiments. [ABSTRACT FROM AUTHOR]

Green methanol is considered an important future hydrogen carrier in the maritime sector, however, its wide scale use is expected to be limited by the scarcity of biogenic carbon. This paper proposes a concept where onboard carbon capture (OCC) is used to facilitate a cyclic use of biogenic carbon by storing the captured CO 2 which can be re-used to produce new green methanol. To enable this concept a novel methanol-fueled solid oxide fuel cell system with cryogenic CO 2 capture partly using absorption cooling is proposed. Three configurations of this system are developed. Based on steady-state thermodynamic models, it was found that the best system configuration was able to reach a steam-to-carbon ratio of 2, a system fuel utilization of 100%, zero emissions, and a lower heating value electrical system efficiency of 63.9%. This is on a par with the best power generation and OCC systems currently proposed in the literature. [Display omitted] • Three SOFC system configurations with onboard carbon capture are modeled. • The concept introduces circular use of CO 2 separated using absorption cooling. • Best performing configuration operates with 64%–65% LHV-based efficiency. • Very high efficiencies at part-load operation of the system. • 100% carbon capture rate and fuel utilization in two out of three configurations. [ABSTRACT FROM AUTHOR]

Sustainable methanol formation from CO2/H2 is potentially a key process in the post-fossil chemical industry. In this study, Hf- and Zr-based metal-organic framework (MOF) materials with UiO-67 topology, functionalized with Pt nanoparticles, have been tested for CO2 hydrogenation at 30 bar and 170–240°C. The highest methanol formation rate, 14 molmethanol molPt−1 h−1, was obtained over a Hf-based catalyst, compared with the maximum of 6.2 molmethanol molPt−1 h−1 for the best Zr-based analogue. However, changing the node metal did not significantly affect product distribution or apparent activation energy for methanol formation (44–52 kJ mol−1), strongly indicating that the higher activity of the Hf-based analogues is associated with a higher number of active sites. Both catalysts showed stable catalytic performance during testing under kinetic conditions, but the addition of 2 vol% water to the feed induced catalyst deactivation, in particular the Hf-MOFs. Interestingly, mainly methanol and methane formation rates decreased, while CO formation rates were less affected by deactivation. No direct correlation was found between catalytic stability and framework stability (crystallinity, specific surface area). Experimental and computational studies suggest that water adsorption strength to the MOF node may affect the relative catalytic stability of Hf-UiO-67-Pt versus Zr-UiO-67-Pt methanol catalysts. This article is part of the discussion meeting issue 'Green carbon for the chemical industry of the future'. [ABSTRACT FROM AUTHOR]

As part of its move towards net zero, the chemical industry, over time, will transition away from fossil-based chemical feedstocks towards more sustainable, 'green' carbon—biomass, recycled waste and captured carbon dioxide. One gateway to transforming these feedstocks into the vital chemicals and fuels society relies on is via synthesis gas or 'syngas'—a gaseous mixture of chemical building blocks (H2, CO and CO2). While today the majority of syngas is produced via steam reforming of natural gas, commercially available technologies are enabling syngas production and transformation from sustainable feedstocks. The optimization of sustainable syngas technologies would not be possible without the integrated development of both catalyst and process technology and the associated skills in chemistry and chemical engineering. This paper covers three example technologies that are unlocking the role of syngas as a gateway to sustainable fuels and chemicals and highlights the innovative developments in catalyst and process design that have enabled their optimization and commercialization. This article is part of the discussion meeting issue 'Green carbon for the chemical industry of the future'. [ABSTRACT FROM AUTHOR]

N‐monomethyl amines are useful intermediates in drugs, natural products, paints. Yet their synthesis is a tremendous challenge due to their high reactivity, typically leading to overmethylation. In this contribution, a highly selective catalytic N‐methylation methodology is reported, converting urea derivatives to monomethylated amines, using a commercially available heterogeneous Pd/C catalyst and methanol as unique reagent. Methanol provides a sustainable alternative protocol for the selective preparation of mono‐methylated derivatives as it acts as both H2 and C1 sources. In addition, several control experiments were performed to provide a proposal for the mechanism, namely dehydrogenation of methanol and subsequent hydrogenation of urea derivatives, followed by reduction of the in situ formed methyl imine. Importantly, the approach is simple, highly productive and enables novel synthetic procedures for the preparation of monomethylamines from urea derivatives. [ABSTRACT FROM AUTHOR]

We herein present a novel and an unexpected method for the synthesis of α-ketothioesters by the reaction of pyrrolidine with α-oxodithioesters followed by treatment with methyl iodide in methanol. One of the synthetic applications of α-ketothioesters for the synthesis of 2-acylbenzimidazoles by acid-catalyzed cyclocondensation with benzene-1,2-diamines is described. The probable mechanisms of formation of α-ketothioesters and 2-acylbenzimidazoles are proposed. [ABSTRACT FROM AUTHOR]

Herein we describe a facile methodology for the synthesis of heterocyclic molecules such as 2‐aryl‐substituted imidazolines, oxazolines and 1,4,5,6‐tetrahydropyrimidines, under one‐pot and metal‐free conditions. A series of electron‐poor substituted benzonitriles were used as starting materials with different available diamines and amino alcohols, producing the desired products in good to high yields within methanol and in the absence of catalyst or additives. This methodology can be easily scaled up to laboratory size of 3 mmol for both five‐ and six‐membered heterocycles. Detailed mechanistic and theoretical studies supported the dual role of methanolic media as solvent and as mediated agent. To shed light on the reaction mechanism, DFT mechanistic studies suggest a distinction in the first step, with the activation of the nitrile by methanol, and the formation of a benzimidamide and/or a benzimidate (observed by NMR) as intermediates. This facile synthetic procedure provides a green, metal‐free, and mild protocol for the synthesis of a series of imidazoline, oxazoline and tetrahydropyrimidine derivatives. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction to value‐added fuels displays an attractive scenario to enhance energy supply and reduce global warming. We report herein the confinement synthesis of polymeric carbon nitride (PCN) incorporating with Cu single atoms (CuSAs) inside the crystalline UiO‐66‐NH2, which combines the merits of heterojunction photocatalysis and single‐atom catalysis (SAC) to achieve high‐performance CO2‐to‐CH3OH conversion. A series of spectral studies displays the formation of CuSAs@PCN inside the crystalline UiO‐66‐NH2. Remarkably, the ternary composite shows an excellent photocatalytic turnover frequency of 4.15 mmol ⋅ h−1 ⋅ g−1 for CO2‐to‐CH3OH conversion. Theoretical and experimental studies demonstrate the doping of CuSAs, as well as the formation of type‐II heterojunction, are causal factors to achieve CH3OH generation. The study provides new insights designing high‐performance photocatalyst for CO2 conversion to fuels at atomic scale. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction to value‐added fuels displays an attractive scenario to enhance energy supply and reduce global warming. We report herein the confinement synthesis of polymeric carbon nitride (PCN) incorporating with Cu single atoms (CuSAs) inside the crystalline UiO‐66‐NH2, which combines the merits of heterojunction photocatalysis and single‐atom catalysis (SAC) to achieve high‐performance CO2‐to‐CH3OH conversion. A series of spectral studies displays the formation of CuSAs@PCN inside the crystalline UiO‐66‐NH2. Remarkably, the ternary composite shows an excellent photocatalytic turnover frequency of 4.15 mmol ⋅ h−1 ⋅ g−1 for CO2‐to‐CH3OH conversion. Theoretical and experimental studies demonstrate the doping of CuSAs, as well as the formation of type‐II heterojunction, are causal factors to achieve CH3OH generation. The study provides new insights designing high‐performance photocatalyst for CO2 conversion to fuels at atomic scale. [ABSTRACT FROM AUTHOR]

This study investigates the effect of hydrogen enrichment in a direct-injected methanol-fuelled SI engine, with combustion and emission performance analysed by varying the methanol injection timing from 150° to 60° CA bTDC. A three-dimensional computational fluid dynamic model of the hydrogen-enriched methanol engine was developed to predict the engine performance, in-cylinder, and emission characteristics. The numerical model was solved using three-dimensional Reynolds-Averaged Navier Stokes, the RNG k-epsilon model for turbulence, the O'Rourke and Amsden sub-model for heat transfer, the extended Zeldovich mechanism for nitric oxide emissions, and the Hiroyasu-NSC model for soot emissions. The results indicated that retarding the injection timing resulted in a decrease in the indicated specific CO and soot emissions along with a rise in the indicated specific NOx emissions. Furthermore, hydrogen enrichment with methanol enhanced the hydroxyl radical concentration, reduced the combustion duration, reduced also the indicated specific CO and soot emissions while increasing the indicated specific NOx emissions. The study indicates that hydrogen enrichment could extend the late injection timing limit of methanol by enhancing fuel-air mixing, which improves and controls the combustion process more effectively. • Hydrogen enrichment extended the late injection limit of methanol. • Injection timing improved fuel-air mixing and controlled combustion process. • Methanol performance was limited for high hydrogen additions. • Hydrogen addition to methanol enhanced mixing and combustion. [ABSTRACT FROM AUTHOR]

Efficient real-time power optimization of direct methanol fuel cell (DMFC) system is crucial for enhancing its performance and reliability. The power of DMFC system is mainly affected by stack temperature and circulating methanol concentration. However, the methanol concentration cannot be directly measured using reliable sensors, which poses a challenge for the real-time power optimization. To address this issue, this paper investigates the operating mechanism of DMFC system and establishes a system power model. Based on the established model, reinforcement learning using Q-learning algorithm is proposed to control methanol supply to optimize DMFC system power under varying operating conditions. This algorithm is simple, easy to implement, and does not rely on methanol concentration measurements. To validate the effectiveness of the proposed algorithm, simulation comparisons between the proposed method and the traditional perturbation and observation (P&O) algorithm are implemented under different operating conditions. The results show that proposed power optimization based on Q-learning algorithm improves net power by 1% and eliminates the fluctuation of methanol supply caused by P&O. For practical implementation considerations and real-time requirements of the algorithm, hardware-in-the-loop (HIL) experiments are conducted. The experiment results demonstrate that the proposed methods optimize net power under different operating conditions. Additionally, in terms of model accuracy, the experimental results are well matched with the simulation. Moreover, under varying load condition, compared with P&O, proposed power optimization based on Q-learning algorithm reduces root mean square error (RMSE) from 7.271% to 2.996% and mean absolute error (MAE) from 5.036% to 0.331%. • Proposed power optimization method considers the overall power of the DMFC system. • Methanol supply control can be achieved without requiring concentration information. • Application of Q-learning algorithm is simple, real-time, and greatly reduce the complexity. [ABSTRACT FROM AUTHOR]

The article reveals the potential of using methanol as an ecologically clean fuel for ships today to solve the problem of reducing environmental pollution in the marine industry. The advantages of its use in the marine sector are given in comparison with other types of alternative fuels. Features of modernization of diesel engines for operation on methanol fuel are considered. It was established that by 2050, methanol is to occupy about 70% of the target global low-carbon fuel market. The main methods of methanol production are considered. A new methanol production technology was proposed, which involves the joint use of biomass and natural gas as raw materials. The advantage of the technology is that the heat obtained in the process of autothermal reforming during the conversion of natural gas can be used in making synthesis gas from biomass, which will increase the outcome of the fi nished product by 30% in total due to green methanol, a renewable fuel. New technological approaches and rational use of energy resources make it possible to reduce specifi c production costs and, under appropriate conditions, obtain methanol at a lower cost than that by carrying out each of the processes separately. The implementation of this technology will establish methanol as an economically effi cient alternative fuel that causes less environmental damage and can eff ectively compete with traditional fuels in marine transport. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have great potential for the adsorption of minor molecular alcohols in the vapor phase. However, the drawbacks of powdered MOFs, including low recyclability and problematic separation, limit their application in fermented wine. Chitosan (CS) is a low‐cost, eco‐friendly, moldable matrix used in the food industry. In this study, a novel CS@ZIF‐8 adsorbent with excellent microporous surface area was successfully synthesized by incorporating hydrophobic ZIF‐8 into CS. The results showed that CS@ZIF‐8 beads had a high adsorption affinity for methanol at a Zn2+/2‐methylimidazole molar ratio of 1:5. The adsorption mechanism of methanol on CS@ZIF‐8 beads was systematically studied by X‐ray photoelectron spectroscopy, isotherms, and kinetics. The Langmuir model calculated the maximum adsorption of methanol to 56.8 mg/g. Adsorption kinetics are consistent with pseudo‐second‐order models. Furthermore, CS@ZIF‐8 beads presented excellent recyclability for removing methanol for five consecutive cycles. It could treat 60 bed volumes of Chinese yellow wine in column filtration experiments to make the concentration below 50 mg/L. In summary, the highly efficient CS@ZIF‐8 adsorbent has great potential for methanol adsorption from fermented wines. Practical Application: Methanol will exhibit adverse symptoms such as weakness and headaches after it is ingested. Therefore, methanol control is an important safety factor in the production of fermented wine. The adsorption method is recognized as a widely used technique due to its high efficiency and selectivity. The CS@ZIF‐8 adsorbent synthesized in this paper provides a new idea for methanol removal. [ABSTRACT FROM AUTHOR]

This work presents the results of a study on the effect of ionic surfactants: cationic hexadecyltriammonium bromide (CTAB) and anionic sodium salt of sulfonic acid (1OSASS) on the Bi(III) electroreduction process in mixed aqueous–organic supporting electrolyte solutions containing methanol. This study showed that the composition of the supporting electrolyte solution, particularly the methanol and surfactant concentrations, significantly affects the mechanism and rate of the Bi(III) ion electroreduction. Analysis of the influence of the indicated factors on the mechanisms and kinetics of metal ion electroreduction can contribute not only to the optimization of industrial electrochemical processes but also to the development of innovative technological solutions, such as advanced electrochemical materials and novel sensors. In these experiments, an innovative electrode made of cyclic renewable liquid silver amalgam (R-AgLAFE) was used as a working electrode, which stands out among classic mercury electrodes (HMDE type) due to the significant reduction in mercury consumption while maintaining similar performance. [ABSTRACT FROM AUTHOR]

To eliminate the problem of the aging of cellulose insulation in the manufacturing stage, a new drying method is being developed based on the use of methanol vapors. Previous studies have shown that the complete removal of methanol from the cellulose insulation after the drying process is very difficult. Therefore, it is necessary to check how the remaining methanol after drying affects the properties of both the cellulose materials and mineral oil. To conduct such studies, it is necessary to know the methanol content in oil that can be expected depending on its initial content in the cellulose materials and the temperature of the insulation system. Therefore, the main goal of this work is to develop methanol equilibrium curves for oil–paper insulation. To achieve the assumed goal, three-stage studies were conducted. A gas chromatograph equipped with a flame ionization detector was used in all stages of these studies. The gas partition coefficient between oil and air was determined for a temperature of 70 °C. The key experimental finding was the development of methanol equilibrium curves for oil–paper insulation. Thanks to this achievement, it is possible to estimate the methanol content in cellulose materials and mineral oil depending on the insulation temperature. Such data are necessary, among others, to plan appropriate studies aimed at assessing the impact of methanol content on the dielectric and physicochemical properties of these materials, important from the point of view of the operation of power transformers. [ABSTRACT FROM AUTHOR]

The cement industry significantly impacts the environment due to natural resource extraction and fossil fuel combustion, with carbon dioxide (CO2) emissions being a major concern. The industry emits 0.6 tons of CO2 per ton of cement, accounting for about 8% of global CO2 emissions. To meet the 13th United Nations Sustainable Development Goal, cement plants aim for carbon neutrality by 2050 through reducing CO2 emissions and adopting Carbon Capture and Utilization (CCU) technologies. A promising approach is converting CO2 into valuable chemicals and fuels, such as methanol (MeOH), using Power-to-Liquid (PtL) technologies. This process involves capturing CO2 from cement plant flue gas and using hydrogen from renewable sources to produce renewable methanol (e-MeOH). Advancing the development of novel, efficient catalysts for direct CO2 hydrogenation is crucial. This comprehensive mini-review presents a holistic view of recent advancements in CO2 catalytic conversion to MeOH, focusing on catalyst performance, selectivity, and stability. It outlines a long-term strategy for utilizing captured CO2 emissions from cement plants to produce MeOH, offering an experimental roadmap for the decarbonization of the cement industry. [ABSTRACT FROM AUTHOR]

Biofuels are the most essential types of alternative fuels, which currently have significant potential to reduce CO2 emissions compared to fossil fuels. Methanol is a more efficient fuel than petrol due to its physicochemical properties, such as a higher latent heat of vaporization, research octane number, and heat of combustion of the fuel–air mixture. Also, biomethanol is cheaper than traditional petrol and diesel fuel for agricultural countries. The authors have proposed a new approach to improve the characteristics and efficiency of methanol diesel engines by using biomethanol mixed with hydrogen instead of pure biomethanol. Using a hydrogen–biomethanol mixture in modern engines is an effective method because hydrogen is a carbon-free, low-ignition, highest-flame-rate, high-octane fuel. A small quantity of hydrogen added to biomethanol and its combustion in an engine with a heat exchanger increases the combustion temperature and heat release, increases engine power, and reduces fuel consumption. This article presents experimental results of methanol combustion and a hydrogen-in-methanol mixture if hydrogen was retained due to the utilization of the heat of the exhaust gases. The tests were carried on a single-cylinder experimental engine with an injection of liquid methanol and gaseous hydrogen mixtures. The experiments showed that green hydrogen generated onboard the car due to the utilization of heat significantly reduced fuel costs of engines of vehicles and technological installations. It was established a hydrogen gaseous mixture addition of up to 5% by mass to methanol requires a corresponding change in the coefficient of excess air to λ = 1.25. Also, using an additional hydrogen mixture requires adjustment at the ignition moment in the direction of its decrease by 4–5 degrees of the engine crankshaft. Hydrogen gas mixture addition reduced methanol consumption, reaching a maximum reduction of 24%. The maximum increase in power was 30.5% based on experimental data. The reduction in the specified fuel consumption, obtained after experimental tests of the methanol research engine on the stand, can be implemented on the vehicle engines and technological installations equipped with an onboard heat recovery system. Such a system, due to the utilization of heat and the supply of additional hydrogen, can be implemented for engines that work on any alternative or traditional fuels. [ABSTRACT FROM AUTHOR]

CuO/ZnO/Al2O3 catalyst is commercially employed for methanol manufacturing. The push to enhance the production capacity and reduce CO2 emissions is stimulated by commercial and environmental considerations. Provided that, the present study addressed the assessment of methanol production from the collected CO2-rich off-gas streams in a petrochemical plant by a CAMERE process, which includes a primary reverse water–gas shift reactor (iron-based catalyst) for the conversion of CO2 to CO followed by a conventional methanol reactor (CuO/ZnO/Al2O3 catalyst). The feasibility study is conducted by employing a validated mathematical model. The acquired results demonstrate that the new strategy is capable of intensifying methanol manufacturing (more than 15%, equivalent to 52,500 tonnes per year) and reducing CO2 release (more than 56%). As a whole, running the new plant by employing a two-step off-gas transformation to methanol would result in intensified production capacity and environmental benefits. [ABSTRACT FROM AUTHOR]

The ethyl acetate, ethanol, methanol, and water extracts of cypress from three Tunisian regions (Bizerte, Ben Arous, and Nabeul) were reported for their phenolic content, antioxidant, and antibacterial activities. Cypress extract had an important antiradical and antibacterial potential which was strongly related to the organoleptic quality of the extract which appeared strongly region dependent. The highest contents of polyphenols were obtained in the methanol extract at the region of Bizerte (315.75 mg GAE/g DW). Cupressuflavone was the major compound with high proportions in methanol extract of Bizerte (68%). Amentoflavone also constituted an important flavonoid compound presented in higher proportion in the ethyl acetate extract of Ben Arous (21.2%). For Gram-positive bacteria strains, Staphylococcus aureus was sensitive to the ethanol extract of Nabeul with IZ = 40 mm. This study suggests cypress as potential natural source of antioxidants and antibacterial agents. [ABSTRACT FROM AUTHOR]

Synthesis of renewable isoprene continues to attract significant interest, yet catalysts still need improvement for industrial applications. We report herein an efficient and novel Prins tandem approach for highly selective production of isoprene from bio‐based methanol and isobutene over Mo‐Fe−O and MgO/Mg(OH)2 acid‐base bifunctional catalysts. Hydration decreases the number of strong basic sites O2− ions and increases OH groups over MgO, thus improving the isoprene selectivity. Basic OH on Mg(OH)2 promotes the Prins condensation of formaldehyde and isobutene, while acidic OH promotes dehydration of isoprenol to isoprene. Suitable contents and proportions of basic and acidic OH groups over Mg(OH)2 increase isoprene selectivity and methanol conversion to 90 and 92 % on the Mo‐Fe−O+Mg(OH)2 composite catalysts, respectively. It exhibits good recycling stability, with isoprene selectivity remaining 90 % after five successive regenerations. DFT calculations reveal OH groups formed after hydration reduce the energy barrier of the H transfer step, thereby promoting the overall reaction. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of new 4a,7a‐diarylperhydroimidazo[4,5‐e][1,2,4]triazine‐3‐thiones were synthesized from 4,5‐diaryl‐4,5‐dihydroxyimidazolidin‐2‐ones and thiosemicarbazide in high yields, and their interaction with ethyl phenylpropiolate was studied. An effective method for the regioselective synthesis of imidazo[4,5‐e][1,3]thiazino[3,2‐b][1,2,4]triazines as new heterocycic system derivatives was proposed based on the reaction of aforementioned imidazotriazinethiones with ethyl phenylpropiolate in the presence of MeONa in methanol. The reaction is initiated by a Michael‐type addition of the imidazotriazinethiones to the triple bond of ethyl phenylpropiolate followed by intramolecular cyclization. [ABSTRACT FROM AUTHOR]

Methanol is recognized as source of hydrogen production, making it a suitable fuel for sustainable development. However, hydrogen production methods remain a concern. An experimental setup and a simulation model in Aspen Plus, incorporating an evaporator and cracker, are developed for hydrogen production. The effects of dimensional parameters, including the length and diameter of the cracker, temperature, and pressure in the presence of the catalyst SCST- 403, on hydrogen production and methanol conversion via thermal catalytic cracking have not been discussed yet . The experimental results show that the optimum hydrogen mole fraction exceeds 0.52, and methanol conversion exceeds 60% at a length of 2.83 m, diameter of 4.07 mm, temperature of 500 °C, and pressure of 2.7 MPa. The investigation is extended to redesign the cracker unit using Aspen Plus based on reaction kinetics. Simulations on various dimensions, temperatures, and pressures reveal that, after redesigning, the optimum hydrogen mole fraction exceeds 0.60, and methanol conversion reaches 85% at a length of 4.5 m, diameter of 5.2 mm, temperature of 500 °C, and pressure of 3 MPa. [Display omitted] • Design a compact-size methanol cracking unit for hydrogen production. • Utilize high temperature conditions for faster methanol catalytic cracking. • On-board syn-gas production, primarily hydrogen, by methanol decomposition. • Design variations aim to enhance methanol cracking and hydrogen production efficiency. [ABSTRACT FROM AUTHOR]

The direct conversion and efficient utilization of methane pose a critical scientific challenge. Indirect activation via reactive oxygen species (ROS) offers a high probability of contact with methane and conversion efficiency under mild conditions. However, reported product yields are suboptimal due to challenges in activating oxygen and facilitating mass transfer in suspension systems. We propose the use of contact‐electro‐catalysis (CEC), employing polydopamine (PDA) as a catalyst that undergoes electron transfer with oxygen under ultrasound, generating ROS that drives the partial oxidation of methane (POM). Corresponding experimental results indicate that CH3OH and most HCHO are produced directly from CH4. Furthermore, through in situ characterizations, we have shown that light pretreatment of the catalysts in an oxygenated atmosphere facilitates the forming of more C=O functional groups with strong electron‐withdrawing properties, thereby significantly enhancing overall product yields, particularly for CH3OH. Within two hours, product yields reach 1.5 mmol gcat−1 for HCHO and 0.9 mmol gcat−1 for CH3OH. This work introduces a novel approach for efficient POM, while highlighting the distinctive catalytic properties of PDA. [ABSTRACT FROM AUTHOR]

The process of removing sulfur compounds and aromatic compounds to produce clean fuel is an important and effective contribution to the processes of mitigating and adapting to climate change. In contrast, it is necessary to find an innovative way to remove sulfur and carcinogenic aromatic compounds because clean, low-sulfur diesel is commonly used in all countries of the world at the present time. Therefore, in this work, we have studied the effect of the microwave radiation power and the irradiation time with the use of more than one type of organic solvent; methanol, acetonitrile and ethyl acetoacetate; as an extractant and solvent to feed ratio impact on the removal of sulfur and aromatic compounds of a real diesel fuel feed which has 450 ppm sulfur content and 16 wt% aromatic Content. The results showed that the best solvent used during this work was ethyl acetoacetate. According to the results, high sulfur removal (≈ 92%) was accomplished with microwave-assisted extractive desulfurization technique under the following ideal conditions: the irradiation time is 7 min, the solvent feed ratio is 3:1 and the microwave intensity is 180 W. To reveal the mechanism of microwave-assisted extractive desulfurization via different organic solvents, a theoretical study including structural examination and interaction energy analysis on the interaction between dibenzothiophene (DBT) or dimethyl dibenzothiophene (DMDBT) and the different organic solvents was also conducted. [ABSTRACT FROM AUTHOR]

This work presents the PULPO (Python‐based user‐defined lifecycle product optimization) framework, developed to efficiently integrate life cycle inventory (LCI) models into life cycle product optimization. Life cycle optimization (LCO), which has found interest in both the process systems engineering and life cycle assessment (LCA) communities, leverages LCA data to go beyond simple assessments of a limited number of alternatives and identify the best possible product systems configuration subject to a manifold of choices, constraints, and objectives. However, typically, aggregated inventories are used to build the optimization problems. Contrary to existing frameworks, PULPO integrates whole LCI databases and user inventories as a backbone for the optimization problem, considering economy‐wide feedback loops between fore‐ and background systems that would otherwise be omitted. The open‐source implementation combines functions from Brightway2 for the manipulation of inventory data and pyomo for the formulation and solution of the optimization problem. The advantages of this approach are demonstrated in a case study focusing on the design of optimal future global green methanol production systems from captured CO2 and electrolytic H2. It is shown that the approach can be used to assess sector‐coupling with multi‐functional processes and prospective background databases that would otherwise be impractical to approach from a standalone LCA perspective. The use of PULPO is particularly appealing when evaluating large‐scale decisions that have a strong impact on socioeconomic systems, resulting in changes in the technosphere on which the background system is based and which is often assumed constant in standard LCO approaches regardless of the decisions taken. This article met the requirements for a gold‐gold JIE data openness badge described at http://jie.click/badges. [ABSTRACT FROM AUTHOR]

ZnO/ZrO2 catalysts have shown better activity in the CO2 hydrogenation to methanol compared with single component counterparts, but the interaction between ZnO and ZrO2 is still poorly understood. In particular, the effect of the ZrO2 support phase (tetragonal vs. monoclinic) was not systematically explored. Here, we have synthesized ZnO/ZrO2 catalysts supported on tetragonal ZrO2 (ZnO/ZrO2‐t) and monoclinic ZrO2 (ZnO/ZrO2‐m), which resulted in the formation of different ZnOx species, consisting of sub‐nanometer ZnO moieties and large‐sized ZnO particles, respectively. ZnO/ZrO2‐t exhibited a higher methanol selectivity (81 vs. 39 %) and methanol yield (1.25 vs. 0.67 mmol g−1 h−1) compared with ZnO/ZrO2‐m. The difference in performance was attributed to the redox state and degree of dispersion of Zn, based on spectroscopy and microscopy results. ZnO/ZrO2‐t had a high density of ZnOx‐ZrOy sites, which favored the formation of active HCOO* species and enhanced the yield and selectivity of methanol along the formate pathway. Such ZnO clusters were further dispersed on ZrO2‐t during catalysis, while larger ZnO particles on ZnO/ZrO2‐m remained stable throughout the reaction. This study shows that the phase of ZrO2 supports can be used to control the dispersion of ZnO and the catalyst surface chemistry, and lead to enhanced catalytic performance. [ABSTRACT FROM AUTHOR]

The carbonyl‐alkyne metathesis reaction is a powerful method for the synthesis of α,β‐unsaturated carbonyls. We now report on the development of a halogen‐bond catalyzed protocol for both the intra‐ and intermolecular reaction. Our studies revealed that methanol is a highly efficient solvent and that a very broad range of functional groups are tolerated under the reaction conditions. Mechanistic studies support the proposed halogen‐bond interaction. Furthermore, the halogen‐bond protocol is compared with other available catalytic systems for these reactions. [ABSTRACT FROM AUTHOR]

The increasing anthropogenic carbon dioxide emissions (CO2) have a huge environmental impact, and CO2 emission reduction is already a common view in our society. Recently, selective hydrogenation of CO2 to methanol has attracted much attention because the process can effectively mitigate CO2 emissions and simultaneously produce high‐value‐added chemicals and fuels. The catalysts play a very important role in achieving high efficiency of CO2 to methanol. As one promising alternative, the alloy catalysts have demonstrated high performance in CO2 hydrogenation to methanol due to their unique geometry and electronic properties. Herein, we review the recent advances in alloy catalysts, including solid solution alloys and intermetallic compounds (mainly Cu‐based, In‐based, Ga‐based, and other alloy catalysts) for heterogeneous catalysis of CO2 hydrogenation to methanol. Moreover, the research ideas and development prospects of alloy catalysts for CO2 hydrogenation to methanol are overviewed to provide the ideas and references for the subsequent research on alloy catalysts for CO2 hydrogenation. [ABSTRACT FROM AUTHOR]

The contemporary focus on global concerns such as carbon dioxide (CO2) emissions impacting the environment and contributing to the energy crisis has prompted exploration into alternatives, with photocatalysis emerging as a potential solution. This research involved the development of a PT (TiO2) photocatalyst, synthesized through the hydrothermal method and enhanced with double co‐catalysts of copper and nickel via the wet impregnation technique. The characteristics of the resulting photocatalysts were comprehensively examined using various techniques, including XRD, Raman, UV‐Vis DRS, surface area and pore analysis, SEM‐EDX, HRTEM, XPS, PL, and EPR. The characterization outcomes revealed that the PT phase comprised anatase, brookite, and rutile. The incorporation of double co‐catalysts was evident through the emergence of new peaks in the XRD diffraction pattern, corroborated by SEM, HRTEM, and XPS analysis. In the activity test, CNT‐4 (Cu−Ni/TiO2‐400) exhibited the highest methanol yield at 772.41 μmole g−1 h−1, followed by CONTT‐4 (CuO−NiTiO3/TiO2‐400) with 750.38 μmole g−1 h−1 after three hours of irradiation using a 300 W xenon lamp, while methanol in PT formed only after three hours of irradiation. The presence of co‐catalysts significantly influenced methanol yield, attributed to the increased active sites for the reaction and the reduced band gap, impacting light absorption optimization and suppressing electron‐hole recombination. In CNT‐4, the formation of Ti3+ associated with oxygen vacancies facilitated the generation of more products. [ABSTRACT FROM AUTHOR]

The binary vapor–liquid equilibria (VLE) of (methyl benzoate + benzyl alcohol) and (methyl benzoate + benzaldehyde) were measured and correlated using activity coefficient models. The measurements were performed using a modified Othmer still at constant pressures of 101.3, 51.3, and 21.3 kPa. The measured data were tested for consistency and correlated using the non-random two-liquid (NRTL), Wilson, and universal quasi-chemical (UNIQUAC) models. The data were also compared with predictive models, such as UNIFAC and the machine learning version of COSMO-SAC. Temperature dependence of the interaction parameters was required to accurately represent the data, covering the pressure range of the experiments. These results can be used to design a purification process for methyl benzoate production. [ABSTRACT FROM AUTHOR]

In the present study, the antioxidant activities and total secondary metabolite amounts of different extracts (methanol, acetone, and water) obtained from the leaf and flower parts of Onopordum bracteatum, which was collected from Muğla (Türkiye) were determined for the first time. Antioxidant activity studies were performed with DPPH, ABTS, ß-Carotene/linoleic acid, FRAP, and CUPRAC methods. Secondary metabolite assays were carried out in order to determine the total phenolic, total flavonoid, and total tannin contents of the extracts. In addition, the toxicities (Brine shrimp) of water extracts and the anthelmintic effects of methanol and water extracts were investigated. The leaf methanol extract of O. bracteatum with the highest antioxidant activity in all tests, except the FRAP test (DPPH: IC50= 0.26 ± 0.01 mg/mL, ABTS: IC50= 0.19 ± 0.003 mg/mL, ß-Carotene/linoleic acid: 72.98 ± 1.31%, CUPRAC: 34.02 ± 1.87 mg TE/g extract, FRAP: 3.96 ± 0.65 mg TE/g extract) used to determine the antioxidant activity was observed to have the highest total phenolic content (5.78 ± 0.24 mg GAE/g extract). The highest total flavonoid (32.17 ± 0.82 mg QE/g extract) and total tannin contents (16.41 ± 1.30 mg CE/g extract) were determined in leaf acetone and flower acetone extracts of O. bracteatum, respectively. Concerning the cytotoxic properties, concentration-dependent activity was seen in O. bracteatum water extracts against brine shrimp. Methanol extracts of O. bracteatum showed better anthelmintic activity than water extracts. The results will provide basic data for studies on the pharmacological and medical use of O. bracteatum. [ABSTRACT FROM AUTHOR]

Compared to steam reforming, methanol aqueous-phase reforming (APR) converts methanol to hydrogen and carbon dioxide at lower temperatures, but also displays lower conversion rates. Herein, methanol APR is studied over the active Pt/Al2O3 catalyst under different operating conditions. Studies were conducted at different temperatures, pressures, methanol mass fractions, and residence times. APR performance was evaluated in terms of methanol conversion, hydrogen production rate, hydrogen selectivity, and by-product formation. The results revealed that an increase in operating pressure and methanol mass fraction had an adverse effect on the APR performance. Conversely, it was found that hydrogen selectivity was unaffected by the operating pressure and residence time for the methanol feed mass fraction of 5%. For the methanol feed mass fraction of 55%, hydrogen selectivity was improved by operating pressure and residence time. The alumina support phase change to boehmite as well as sintering and leaching of the catalytic particles were observed during catalyst stability experiments. Additionally, a comparison between methanol steam reforming (MSR) and APR was also performed. [ABSTRACT FROM AUTHOR]

In this work, non-precious electrocatalysts were synthesized using the electrospinning technique. Ni12M8/CNF (M = Cd, Co, and Cu) catalysts were successfully prepared in a fixed ratio to withstand the optimum transition metal co-catalyst in addition to the role of CNFs as support in ion-charge movement through the catalyst surface. The prepared catalysts were physically studied by XRD, SEM, and TEM. The electrochemical activity was verified using different fuel concentrations, different sweeping scan rates, and electrochemical impedance. Ni12Cu8/CNFs showed the highest electrochemical activity reaching 152 mA/cm2 through different methanol concentrations. The outstanding performance is attributed to the large active surface area provided by carbon nanofibrous that eases the charge carrier transfer through the untrapped surface of the catalyst. The electrochemical tests suggest that Ni12Cu8/CNFs have the lowest ohmic impedance resistance ensuring the highest efficiency of the designed catalyst. The obtained results serve as an efficient catalyst for direct methanol electrooxidation reactions and suggest a possible application of a low-cost, easily accessible, and large surface area established via the preparing method. [ABSTRACT FROM AUTHOR]

Integrated carbon capture and utilization (ICCU) simplifies the CO2 utilization process by converting chemically combined CO2 molecules into value-added chemicals, leading to a strong energy-saving effect by omitting the CO2 separation process. Two reaction routes for the hydrogenation of amine captured CO2 to methanol over heterogeneous catalysts were summarized: alcoholic hydroxyl groups-promoted CO2 hydrogenation process over Cu or Pd-based catalysts via formate and ester route, and methanol production from the direct hydrogenation of formate over Au-based catalyst. The technical effectiveness of concurrent carbon capture with heterogeneous catalysis toward methanol via alcoholic hydroxyl groups-promoted CO2 hydrogenation is similar to that of the gas-phase CO2 hydrogenation to methanol over heterogeneous catalysts. The sintering of the catalysts, the phase change of the supports, the combination of amines and the catalysts (namely leaching), and the reaction of water with the supports can cause a decrease in the performance of the catalysts. Thus, it is important to rationally design next-generation stable catalysts to achieve amine captured CO2 hydrogenation to methanol while at the same time regenerating amines. The development of heterogeneous catalysts for methanol synthesis in the liquid phase and the development of the CO2 capture process for subsequent conversion(1 ~ 70%) were carefully reviewed. The integration and optimization of multi-pollutant efficient removal technology, selectively coupled CO2 capture technology, and selective routes for methanol synthesis can achieve industrial verification in typical power plants, which is of great significance in promoting energy conservation, emission reduction, and low-carbon footprint. [ABSTRACT FROM AUTHOR]

Methanol reportedly stimulates citric acid (CA) production by Aspergillus niger and A. tubingensis ; however, the underlying mechanisms remain unclear. Here, we elucidated the molecular functions of the citrate exporter gene cexA in relation to CA production by A. tubingensis WU-2223L. Methanol addition to the medium containing glucose as a carbon source markedly increased CA production by strain WU-2223L by 3.38-fold, resulting in a maximum yield of 65.5 g/L, with enhanced cexA expression. Conversely, the cexA -complementing strain with the constitutive expression promoter Ptef1 (strain LhC-1) produced 68.3 or 66.7 g/L of CA when cultivated without or with methanol, respectively. Additionally, strain LhC-2 harboring two copies of the cexA expression cassette produced 80.7 g/L of CA without methanol addition. Overall, we showed that cexA is a target gene for methanol in CA hyperproduction by A. tubingensis WU-2223L. Based on these findings, methanol-independent CA-hyperproducing strains, LhC-1 and LhC-2, were successfully generated. [ABSTRACT FROM AUTHOR]

Crystals of 1-nitronaphthalene were grown by evaporation of a methanol solution. The structure [P21/c, a = 13.2780(13) Å, b = 3.8131(3)° Å, c = 31.851(3) Å, β = 91.173(8), V = 1,612.3 Å3] was solved from a crystal twinned by twofold rotation about [100]. Twinning is explained by the polytype character: layers with (idealized) p2111 symmetry can connect via either 1‾ or 21 operations, leading to geometrically distinct pairs of layers. In the twin individuals, the two kinds of contacts alternate, at the composition plane two subsequent contacts of the same type are realized. [ABSTRACT FROM AUTHOR]

Background: Methyl alcohol poisoning (MAP) is a common commercial compound that can lead to significant morbidity and mortality when exposed to high levels. This study aims to describe MAP-related electrocardiography (ECG) changes and post-acute late complications. Materials and Methods: The study was conducted through a retrospective data review between 2017 and 2023. Patient data were recorded, including demographic information, medication use, and laboratory results. Twelve-lead ECG recordings were evaluated and the results were recorded. The cases included in the study were grouped according to QTc distance, ECG findings, late-term complications, treatment status, and mortality. Results: The mean age of all cases included in the study (n = 227) was 43.23 ± 11.11 years, 8 (3.5%) cases were female, and the age distribution was between 19 and 68 years (p = 0.792). The age distribution of QTc groups was not significant (p = 0.792). The mean QTc distance was 442.7 ± 60.1 ms in all cases (n = 227) and 514.08 ± 5.45 ms in cases with mortality (n = 49) (p < 0.001). The mean time to application of the patients to the hospital (n = 227) was 19.1 ± 4.61 h, and blood sugar was 130.7 ± 32.09 mg/dL (p < 0.001). In addition, the mean pH of the cases (n = 227) was 7.14 ± 0.2, bicarbonate was 17.17 ± 4.86 mmol/L, the base deficit was −6.21 ± 3.18 mmol/L, the anion gap was 19.36 ± 7.31 mmol/L, and lactate was 4.82 ± 2.45 mmol/L (p < 0.001). Mortality occurred in 49 (21.6%) of the patients, and all of them were in-hospital deaths. In all cases where mortality occurred, pH was below 6.93 ± 0.22 and severe acidosis was directly related to death. MAP, sinus tachycardia in 31 (13.7%) cases, bradycardia in 8 (3.5%), atrial fibrillation in 5 (2.2%), accelerated idioventricular rhythm in 3 (1.3%), and 11 (4.8%), left bundle branch block, and right bundle branch block were detected in 22 (9.7%). All of these ECG findings were newly developed conditions with no previous history. In the 6-month follow-up after discharge, 4 (1.8%) of the cases developed neurological deficit, 15 (6.6%) had acute coronary syndrome and severe heart failure, 23 (10.1%) had permanent blindness, 6 (2.7%) had renal failure, and 6 (2.7%) had pancreatitis. Conclusions: Methyl alcohol poisoning can cause various ECG changes; sinus tachycardia, nonspecific changes, and QTc prolongation are the most common findings. These changes are more pronounced in cases of severe acidosis. Patients should be warned of late signs of MAP. [ABSTRACT FROM AUTHOR]

The purpose of this work was to study the synthesis and characterization of an adhesive based on a glucose stabilized polyvinyl acetate homopolymer. Vinyl acetate monomer was stabilised onto liquid glucose using emulsion polymerization, and polymerization happened using potassium persulfate as an initiator. Here, the effects of adding liquid glucose as a stabiliser for adhesives were studied. Therefore, the current research examines whether liquid glucose, introduced at weight-based concentrations of 0.5% and 1.0%, is suitable as a colloid to produce PVAc adhesives for wood. By measuring viscosity, pH, contact angle, differential scanning calorimetry (DSC), and the pencil hardness test of films, the effect of adding liquid glucose as a colloid on physical, thermal, and mechanical properties was investigated. The shear strength of the PVAc homopolymers applied to wood using emulsions with varied liquid glucose concentrations was measured using a universal tensile machine. As the concentration of liquid glucose increased, the viscosity of the adhesives also considerably increased. Water resistance significantly rose when liquid glucose content increased, as was found by measuring the water contact angle. The use of liquid glucose increased the hardness of PVAc films, which was supported by the glass transition temperature. According to EN 204-205, the tensile shear strength with 1.0% of liquid glucose increased by 63.88% and 45.67%, respectively, over a pristine sample after 6 h of bonding in a dry environment and 24 h in a wet environment. The study's overall conclusion highlights the higher adhesion capability of PVAc emulsion-based adhesives stabilized by liquid glucose. [ABSTRACT FROM AUTHOR]

Tetrapyrrolic containing metal complexes are among the most efficient molecular catalysts for the CO2 reduction. Metalloporphyrins and phthalocyanines are currently under investigations and their catalytic properties are among the best molecular catalysts. Corrole, a contracted tetrapyrrolic macrocycle has been also used to design molecular for the CO2 reduction. The electrochemical activity towards CO2 reduction can rival those of their porphyrin analogues. However, the catalytic activity of the metallocorrole is initiated at the corresponding MII/I couple. Accordingly, a catalytic current in presence of CO2 with cobalt corrole appears when the CoI species is generated. We have designed an electron deficient A2B corrole holding two −CF3 groups and a benzonitrile in the meso positions and its cobalt complex (1). We reasoned that these groups could shuffle the redox potentials to reach the M(I) oxidation states at more positive values thereby lowering the overpotential for the catalytic CO2 reduction. Our results clearly show that catalyst 1 when adsorbed on a carbon electrode, shows the most favourable catalytic performance for CO production, achieving an efficiency of 85 % with a current density of −1.5 mA cm−2 at −1.0 V vs NHE. The current densities of controlled potential electrolysis with increasing amount of KHCO3, were found to increase more than one order of magnitude with the formation of MeOH. [ABSTRACT FROM AUTHOR]

The antioxidant and anticancer potential of solvent extracts of the leaf, stem bark, fruit, and seeds of Embelia ruminata was investigated. The chloroform seed extracts had the highest TAC of 38.50 mg AAE g−1 DW. In the FRAP and DPPH assays, the methanolic seed extracts exhibited the most effective activity (67.63 mg AAE g−1 and IC50 of 3.54 µg mL−1, respectively), compared to the respective standards. In the MTT assays, the hexane seed extracts were the least cytotoxic and had a more pronounced effect on MCF-7 and A549 cell lines (IC50 of 93.1 and 119.5 µg mL−1, respectively) than the control. [ABSTRACT FROM AUTHOR]

The apoptotic potential of Ficus religiosa bark methanol extract (FRme) was examined using MDA-MB-231 breast cancer cells. MDA-MB-231 cell cytotoxicity by FRme was dose-dependent with EC50 of 91.32 ± 4.21 μg mL−1 however, it was non-toxic to normal cell line (HEK 293 T). Apoptosis identified by flow cytometer showed 32.5% cells in apoptosis and 61.6% in late apoptosis. FRme blocked cell cycle growth and proliferation at the G1/S phase. An increased expression of BAX with the proteolytic cleavage of PARP-1 and a downregulation of Bcl-2 levels by Western blot was recorded. Confocal microscopy studies identified chromatin condensation and loss of nuclear structures in apoptotic cells. UPLC-MS analysis of FRme for novel bioactives identified rutin, 3-caffeoylquinic acid, luteolin 7-O-rutinoside, 6-C-glucosyl-8-C-arabinosylapigenin, and kaempferol-3-O-rutinoside. [ABSTRACT FROM AUTHOR]

Background: β-Arbutin, found in the leaves of bearberry, stands out as one of the globally acknowledged eco-friendly whitening additives in recent years. However, the natural abundance of β-Arbutin is low, and the cost-effectiveness of using chemical synthesis or plant extraction methods is low, which cannot meet the requirements. While modifying the β-Arbutin synthesis pathway of existing strains is a viable option, it is hindered by the limited synthesis capacity of these strains, which hinders further development and application. Results: In this study, we established a biosynthetic pathway in Komagataella phaffii for β-Arbutin production with a titer of 1.58 g/L. Through diverse metabolic strategies, including fusion protein construction, enhancing shikimate pathway flux, and augmenting precursor supplies (PEP, E4P, and UDPG), we significantly increased β-Arbutin titer to 4.32 g/L. Further optimization of methanol concentration in shake flasks led to a titer of 6.32 g/L titer after 120 h of fermentation, representing a fourfold increase over the initial titer. In fed-batch fermentation, strain UA3-10 set a record with the highest production to date, reaching 128.6 g/L in a 5 L fermenter. Conclusions: This is the highest yield in the fermentation tank level of using microbial cell factories for de novo synthesis of β-Arbutin. Applying combinatorial engineering strategies has significantly improved the β-Arbutin yield in K. phaffii and is a promising approach for synthesizing functional products using a microbial cell factory. This study not only advances low-cost fermentation-based production of β-Arbutin but also establishes K. phaffii as a promising chassis cell for synthesizing other aromatic amino acid metabolites. [ABSTRACT FROM AUTHOR]

Methanol is being activelPTy investigated as a promising C1 reagent to replace conventional C1 reagents in organic synthesis, due to its properties of being economical, abundant, nontoxic and sustainably producible. However, because of the high enthalpy of dehydrogenation, it has not been reported frequently. Herein, we report that Pt single atoms (Pt1) and Pt clusters (Ptn) are cooperatively loaded on α-MoC to achieve the conversion of various of unsaturated N-containing compounds into value-added N-methylation compounds simply in methanol aqueous solution, successfully avoiding the use of external hydrogen or any additives. The synergy between coexisting Pt1 and Ptn on Pt1+n/α-MoC is identified as necessary to realize the tandem conversion with superior activity and selectivity. Pt1/α-MoC is the active site for in situ hydrogen production from aqueous phase methanol reforming, and Ptn/α-MoC is responsible for the successive hydrogenation and methylation. The partially positive Ptnδ+ species are crucial for the reductive N-methylation reaction, as the strong coordination of N-containing compounds to Pt particles (Ptn) significantly inhibits the catalytic activity. Experimental and DFT results further show that, unlike the traditional hydrogen-borrowing mechanism of methanol via the intermediate formaldehyde, formic acid is found to be a potent intermediate and agent for N-methylation. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction is gaining more interest as a sustainable route to produce methanol, a key starting material in the synthesis of many chemicals and a potential energy carrier. Here, metal‐organic frameworks (MOFs) are used as platforms to integrate plasmonic Au nanospheres and Cu active centers in joint bifunctional hybrid photocatalysts. The methodology followed in obtaining stable Au@UiO‐67‐bpy‐Cu MOFs is based on synthesizing Au@UiO‐67‐bypiridine (bpy) MOFs through a core‐shell procedure, and then modifying them with Cu ions after their coordination with the bpy ligands. This gains the final structure regular coverage of active metal centers that can be excited by the interaction with the plasmonic nanospheres. In the absence of Au, the system demonstrates selectivity toward the formation of methanol under hole scavenger‐free conditions owing to the excitation of the bpy‐Cu complex with visible light. The obtained yield duplicates upon Au nanospheres incorporation as a result of the injection of hot electrons, excited by surface‐mediated intraband processes, to the bpy‐Cu states, thus increasing their CO2 reduction efficiency. Additionally, the catalytic activity remains stable during four consecutive cycles. [ABSTRACT FROM AUTHOR]

The synthesis of tetraarylmethanes has long been a challenge in the field of synthetic chemistry. In this study, a series of tetraarylmethanes were successfully synthesized through the formal nucleophilic substitution reaction of indol-2-yl diaryl methanol catalyzed by Brønsted acid. The key success of this study lies in suppressing the influence of water molecules by forming hydrogen bonds with the TFE solvent. This process leads to the formation of active 2-indole imine methide (2-IIM) intermediates, ensuring the successful synthesis of tetraarylmethanes. Furthermore, some of the products also exhibited potential anticancer activity. [ABSTRACT FROM AUTHOR]