Decomposition Pathways Research Articles

Chronic widespread musculoskeletal pain shares a highly heritable latent pathway with atherosclerosis and arterial stiffness

Abstract Chronic widespread pain (CWP) is prevalent and associated with reduced life expectancy. Cardiovascular disease is one possible mechanism for this. The purpose of this study was to examine the association of CWP with arterial stiffness and carotid plaque measured using ultrasound to determine if shared environmental or genetic factors might account for any observed association. Around 3000 participants from the TwinsUK with CWP information and measures of carotid–femoral pulse wave velocity (cfPWV), carotid intima–media thickness (cIMT), and plaque were considered. The relationship between CWP and cfPWV, cIMT, and plaque was determined. UK Biobank data were used to replicate the association. Cholesky decomposition and multivariate pathway twin models were examined. Using a 2-sample Mendelian randomisation approach, the causal association between CWP and coronary artery disease was assessed. TwinsUK participants demonstrated a significant association between CWP and increased cfPWV consistent with arterial stiffening (OR = 1.35, P-value = 0.012), as well as the presence of carotid plaque (OR = 1.45, P-value = 0.8e-5). The twin modelling showed a common latent component and pathway underlying CWP, cfPWV, and carotid plaque, with genetic factors accounting for 68% and 90% of the latent factor variation, respectively. The 2-sample MR revealed a potential causal association between CWP and coronary artery disease. This study found that those with CWP have increased the risk of arterial stiffness and atherosclerosis and suggests that CWP leads to an increased risk of cardiovascular disease through genetic factors.

Electrochemical formation of bis(fluorosulfonyl)imide-derived solid-electrolyte interphase at Li-metal potential.

Lithium bis(fluorosulfonyl)imide-based liquid electrolytes are promising for realizing high coulombic efficiency and long cycle life in next-generation Li-metal batteries. However, the role of anions in the formation of the solid-electrolyte interphase remains unclear. Here we combine electrochemical analyses and X-ray photoelectron spectroscopy measurements, both with and without sample washing, together with computational simulations, to propose the reaction pathways of electrolyte decomposition and correlate the interphase component solubility with the efficacy of passivation. We discover that not all the products derived from interphase-forming reactions are incorporated into the resulting passivation layer, with a notable portion present in the liquid electrolyte. We also find that the high-performance electrolytes can afford a sufficiently passivating interphase with minimized electrolyte decomposition, by incorporating more anion-decomposition products. Overall, this work presents a systematic approach of coupling electrochemical and surface analyses to paint a comprehensive picture of solid-electrolyte interphase formation, while identifying the key attributes of high-performance electrolytes to guide future designs.

Oxidative Deformylation of the Predominant DNA Lesion 5-Formyl-2'-deoxyuridine.

Radical oxidation of DNA gives rise to potentially deleterious lesions such as strand breaks and various nucleobase modifications including 5-formyl-2'-deoxyuridine (5-fo-dU), a prevalent product derived from the oxidation of the C5-methyl group of thymidine. The present study investigates the unusual transformation of 5-fo-dU into 5-hydroxy-2'-deoxyuridine (5-oh-dU) and 5,6-dihydroxy-5,6-dihydro-2'-deoxuridine (gly-dU), two products typically associated with the oxidation of 2'-deoxycytidine. Detailed mechanistic analyses reveal that hydrogen peroxide, either generated as a byproduct of ascorbate autoxidation or added exogenously, mediates the formation of these oxidatively induced C5-dealkylated products. We show that the major product 5-oh-dU results from a Baeyer-Villiger rearrangement of the formyl functionality of 5-fo-dU while the minor product gly-dU derives from α,β-oxidation of the enal portion followed by deformylation. These reactions were observed in both 2'-deoxynucleoside monomers as well as isolated DNA. Our findings further clarify the oxidation chemistry of thymidine and highlight a novel oxidative decomposition pathway that can help understand the fate of certain types of DNA damage. Furthermore, our results underscore the pro-oxidant properties of ascorbate in vitro that can lead to the adventitious oxidation of substrates via the reduction of trace metals ions and generation of hydrogen peroxide.

Insights into polymer electrolyte stability and reaction pathways: A first-principle calculations study.

To identify suitable polymer candidates for electrolytes in solid-state batteries, this study investigates the electrochemical behavior and decomposition pathways of four monomers involving esters, ethers, and carbonates via first-principles calculations. In particular, we determine the oxidation and reduction potentials of these monomers near different ions (Li+, TFSI-, and [Li]+[TFSI]-) and the corresponding reorganization energies. The latter quantity is central to Marcus theory of electron transfer and, therefore, provides additional kinetic information. Our results reveal notable sensitivity of the monomers to reduction in a Li+-rich regime and to oxidation in a TFSI--rich regime. Additionally, the reactivity and decomposition pathways of the monomers were investigated for various electrochemical environments, focusing on the quantification of gaseous and ionic products during the initial stage of formation of interphasial layers. Based on the electrochemical windows and spontaneous Ab initio molecular dynamics calculations, we observe that monomers containing carbonate groups exhibit greater stability against decomposition caused by reduction, especially in different regimes, when compared to monomers with ester and ether groups.

Soot particle morphology and polycyclic aromatic hydrocarbons formation molecular dynamics during diffusion combustion of three pentanol biofuels

Soot particles constitute a major pollutant in engine diffusion combustion, posing a serious threat to human health and the atmospheric environment. The employment of carbon-neutral biofuel, pentanol, in engines contributes to reducing soot emissions; however, its effectiveness is contingent upon the position of the OH functional group. This work investigated the soot morphology and microstructural parameters evolution of three pentanol isomers, and explored the influence mechanism of OH functional group positional isomerism on the entire process of PAHs formation at the atomic level. The results showed that the peak of primary particle size and soot volume fraction in pentanol flames showed a trend of 2-pentanol>3-pentanol>1-pentanol, and the initial formation time of soot in 1-pentanol flame is the latest, and the particle aggregate size is the smallest. The entire process of pentanol isomers soot formation can be divided into four stages: fuel pyrolysis forming initial ring, PAHs growing into initial soot, soot chain growth and structural evolution, soot morphology transformation and maturation. Among the three isomers, 2-pentanol has the fastest initial ring formation rate, the highest peak C-number in the largest molecule, and ultimately forms a more mature fullerene-like structure. 1-pentanol has the slowest initial ring formation rate, the lowest peak C-number in the largest molecule, ultimately forms a lower maturity layered structure. In terms of reaction pathways, H-atom abstraction and dehydroxylation reactions jointly dominate the initial decomposition pathway in 1-pentanol combustion, while in 2-pentanol, dehydroxylation becomes the main initial decomposition pathway due to the high stability of H atoms on β‑carbon. The dehydroxylation reaction tends to generate olefins, promoting the generation of C1-C4 hydrocarbon. The oxygen atom bonded on the α‑carbon site exhibits a stronger carbon fixation ability, and C1-C4 hydrocarbons are more inclined to participate in oxidation to form CO rather than promote the soot production.

Fabrication of Co(II)-based coordination polymer for photocatalytic degradation: Selective removal of cationic methyl violet dye

In this study, a new coordination polymer (CP) was designed and synthesized to evaluate the photocatalytic properties for water remediation. The Co(II)-based CP {[Co(HL)(bid)(H2O)]·2H2O}n (1) was hydrothermally synthesized using the ligand 5-(4′-carboxyphenoxy)isophthalic acid (H3L) and 1,4-bis(1-imidazolyl)-2,5-dimethylbenzene (bid). The coordination polymer (1) has been characterized by various spectral techniques, thermogravimetric (TGA), and single crystal X-ray technique. X-ray data revealed that (1) exhibits 2D framework having an octahedral coordination geometry around the Co(II) ions, having μ1:η1-η1 mode with chromophore CoO4N. FT-IR analysis confirmed the asymmetric monodentate binding modes of the carboxylate ligand. The CP 1 has demonstrated optical semiconducting properties, rendering them promising candidates for photocatalytic applications. The catalyst (1) has been effectively utilized in the breakdown of several organic dyes, such as methylene blue (MB), methyl orange (MO), methyl violet (MV), and rhodamine B (RhB). The results showed that at pH 4, with a dosage of 30 mg of catalyst (1), 92.08 % of MV was degraded at a concentration of 20 ppm. Additionally, the mechanistic pathway for light-driven MV decomposition was investigated through experimental approaches, specifically radical trapping experiments.

Viability of Extracorporeal Membrane Oxygenation Circuits during Arterio-venous Shunting: An Observational Study of ECMO Circuits

Introduction Trial off veno-arterial extracorporeal membrane oxygenation is often performed by diversion of circuit flow through an arterio-venous shunt. Separation from the patient presents an augmented risk for microbiological growth and deterioration of the circuit components and blood circulating within it. It is unclear how long mechanical components and blood circulating within the circuit remain intact during arterio-venous shunting. Methods Following decannulation, the arterial and venous lines were connected simulating an arterio-venous shunt. Flow was maintained at 500 ml/min. Observations at 11 intervals were paired with blood culture, blood gases, chemistry and coagulation studies. Heparin was not provided in two circuits, and four circuits received 30 IU/hour. Results Of six circuits studied, five maintained flows of 500 ml/min for 48 hours. One circuit developed extensive clot after two hours and blood flow ceased. Microbial growth was not detected. Glucose, fibrinogen and platelet levels reduced progressively from the outset. Cell breakdown was evident by four hours (increase in plasma potassium and phosphate) and lactate rose above 6.3 mmol/L at four hours in all circuits. Conclusion Arterio-venous shunting longer than four hours carries a risk of blood decomposition and cell energy pathway depletion. Re-establishing extracorporeal membrane oxygenation support post arterio-venous shunting carries a risk of physiological derangement, given the blood composition changes during arterio-venous shunting. Consideration should be given to an alternate method to assess the physiological stability of patients off extracorporeal membrane oxygenation prior to decannulation. Alternately, consider a crystalloid flush of the circuit to remove decomposed blood if the trial-off exceeds four hours.

Theoretical investigation of electric field influence on the decomposition species and reaction routes of C4F7N over Cu(111) surface

The use of eco-friendly insulation gas C4F7N as a replacement for the greenhouse gas SF6 is critical for achieving net-zero emissions. However, the discharge-induced decomposition mechanisms of C4F7N on electrode surfaces remain unclear, posing significant challenges to the development of new insulation equipment. In this study, we performed density functional theory (DFT) calculations to investigate the discharge-induced decomposition of C4F7N on the Cu(111) surface. The adsorption energy of decomposition intermediates is influenced by both the strength and polarity of the electric field (E-field) by altering surface charge transfer and orbital interactions. Negative E-fields enhance the adsorption stability, whereas positive E-fields destabilize it. Stable products, such as CF4, C2F6, C3F6, and C3F8, exhibit physical adsorption on Cu(111) and are insensitive to the E-field. The decomposition process of C4F7N follows multiple pathways when it transitions from C4 to C3 species, with the reaction energy closely related to the detachment and desorption of intermediates. A negative E-field reduces the reaction enthalpy and lowers the overall energy of the decomposition pathway, while a positive E-field facilitates the formation of stable CxFy products. This study offers insights into the decomposition mechanism of C4F7N in discharge, providing guidance for the development of new eco-friendly insulation equipment.

Agarase cocktail from agarolytic Alteromonas sp. Aga1552 converts homogenized Gelidium amansii into monosaccharide

Marine algae biomass utilization has attracted considerable attention, however, the preparation of monosaccharides from raw algae is still hindered by many technical barriers. In this study, three genes, aga1365, aga1364, and aga1360, encoding key enzymes constituting a complete agar decomposition pathway were expressed and characterized. Recombinant Aga1365, Aga1364, and Aga1360 exhibited high optimal reaction temperatures and excellent thermal stability. Moreover, enzyme cocktail was proved to have higher synergistic effect to prepare monosaccharide from raw seaweed. The enzyme cocktail of Aga1360 (GH117) with Aga1365 (GH16) and enzyme cocktail of Aga1360 with both Aga1365 and 1364 (GH50) were used to synergistically degrade homogenized Gelidium amansii, maximum monosaccharide production of 21.47 mg/g and 39.28 mg/g could be achieved, respectively. This study presents an environment-friendly, time saving and efficient way to prepare monosaccharides from raw seaweed, which also provide a potential strategy to effectively convert algae biomass for biofuel and biochemical production by utilizing the synergistic effects of enzyme cocktail.

The metabolic engineering of Escherichia coli for the high-yield production of hypoxanthine

BackgroundHypoxanthine, prevalent in animals and plants, is used in the production of food additives, nucleoside antiviral drugs, and disease diagnosis. Current biological fermentation methods synthesize quantities insufficient to meet industrial demands. Therefore, this study aimed to develop a strain capable of industrial-scale production of hypoxanthine.ResultsDe novo synthesis of hypoxanthine was achieved by blocking the hypoxanthine decomposition pathway, thus alleviating transcriptional repression and multiple feedback inhibition, and introducing a purine operon from Bacillus subtilis to construct a chassis strain. The effects of knocking out the IMP(Inosine 5’-monophosphate) branch on the growth status and titer of the strain were then investigated, and the effectiveness of adenosine deaminase and adenine deaminase was verified. Overexpressing these enzymes created a dual pathway for hypoxanthine synthesis, enhancing the metabolic flow of hypoxanthine synthesis and preventing auxotrophic strain formation. Introducing IMP-specific 5’ -nucleotidase addressed the issue of adenylate accumulation. In addition, the metabolic flow of the guanine branch was dynamically regulated by the guaB gene. The supply of glutamine and aspartic acid precursors was enhanced by introducing an exogenous glnA mutant gene, overexpressing aspC, and replacing the weaker promoter to regulate the aspartic acid branching pathway. Ultimately, fermentation in a 5 L bioreactor for 48 h produced 30.6 g/L hypoxanthine, with a maximum real-time productivity of 1.4 g/L/h, the highest value of hypoxanthine production by microbial fermentation reported so far.ConclusionsThe intracellular purine biosynthesis pathway is extensive and regulated at multiple levels in cells. The IMP branch in the hypoxanthine synthesis pathway has a higher metabolic flux. The current challenge lies in systematically allocating the metabolic flux within the branch pathway to achieve substantial product accumulation. In this study, E. coli was used as the chassis strain to construct a dual pathway for IMP and AMP(Adenosine 5’-monophosphate) synergistic hypoxanthine synthesis and dynamically regulate the guanine branch pathway. Overall, our experimental efforts culminated in a high-yield, plasmid- and defect-free engineered hypoxanthine strain.

Bell Test of Quantum Entanglement in Attosecond Photoionization

Attosecond physics enables the study of ultrafast coherent electron dynamics in matter upon photoexcitation and photoionization, revealing spectacular effects such as hole migration and coherent Auger dynamics in molecules. In the photoionization scenario, there has been a strong focus on probing the physical manifestations of internal quantum coherence within the individual parent ion and photoelectron systems. However, quantum correlations between these two subsystems emerging from attosecond photoionization events have thus far remained much more elusive. In this work, we design theoretically and model numerically a direct probe of quantum entanglement in attosecond photoionization in the form of a Bell test. We simulate from first principles a Bell test protocol for the case of noble gas atoms photoionized by ultrashort, circularly polarized infrared laser pulses in the strong-field regime predicting robust violation of the Bell inequality. This theoretical result paves the way for the direct observation of entanglement in the context of ultrafast photoionization of many-electron systems. Our work provides a novel perspective on attosecond physics directed toward the detection of quantum correlations between systems born during attosecond photoionization and unraveling the signatures of entanglement in ultrafast coherent molecular dynamics, including in the chemical decomposition pathways of molecular ions. Published by the American Physical Society 2024

DECOMPOSITION MECHANISM OF ALKYLIDENE BRIDGED TETRAZOLES WITH DIFFERENT CARBON CHAIN LENGTHS.

Nitrogen-rich heterocycles, particularly tetrazole-based high-energy density materials (HEDMs) offer high performance, low sensitivity, and are eco-friendly. Despite the diversity of nitrogen-rich energetic heterocycles, many are sensitive to external stimuli, and the introduction of a methylene, ethylene, or C-C linkage between nitrogen-rich heterocycles is a successful strategy to improve mechanical sensitivity and thermal stability. Understanding the potential anomalous thermal or kinetic behavior of such molecules is crucial for the design of new HEDMs and practical applications of these molecules. We have investigated the influence of introducing an alkylidene bridge between the energetic nitrogen heterocycles on the decomposition mechanism and pathway of different bridged tetrazoles, namely 5,5'-Bis-1H-tetrazole, 1,2-Bis(5-tetrazolo)methane, and 1,2-Bis(5-tetrazolo)ethane, using thermal experiments, mass spectrometry, and computational analysis. Kinetic parameters were evaluated using a non-linear integral method, and decomposition pathways were proposed based on mass fragmentation data. Stability comparisons were made using HOMO-LUMO gap and electrostatic potential (ESP) values from computational calculations.

From germolane to germylenes: a theoretical DFT study of thermal decomposition pathways and reactivity

This study addresses the often-overlooked chemistry of germanium compared to the extensively researched carbon and silicon. Using advanced DFT methods, we investigated the thermal decomposition of germolane (germacyclopentane). The suggested mechanisms include a 1,2-H shift and 1,1-H2 elimination to form a pentacyclic germylene (1λ2-germolane). The other pathway involves a stepwise [3 + 2] cycloreversion to form a diradical followed by ethene and germirane. Under M062X/def2-TZVP level of theory, the activation barriers in terms of Gibbs energy (ΔG ‡ 298) for the 1,2-H shift and 1,1-H2 elimination pathways were 240.9 and 236.3 kJ/mol, respectively. The reaction energies (ΔG° 298) for the initiative steps in the 1,2-H shift and 1,1-H2 elimination mechanisms were 102.9 and 96.2 kJ/mol, indicating a thermodynamic and kinetic competition between the two routes. Temperature dependence analysis from 300 to 1200 K reveals that the 1,1-H2 elimination dominates at higher temperatures and is expected to become spontaneous above 1000 K.

A headspace GC-MS method to quantify nitrosamine impurities and precursors in drug products: Method validation and product testing.

Pharmaceutical manufacturers are working to mitigate the formation of nitrosamine impurities in drug products. The work herein describes the development and validation of a headspace GC-MS method according to ICH Q2(R1) guidelines for the detection and quantification of NDMA, NDEA, NDIPA, and NEIPA in drug products. The analytical procedure was further modified to include detection and quantitation of DMF due to the potential decomposition pathway of DMF to form dimethylamine, a known precursor for NDMA formation. The NDMA impurity was detected in the "sartan" class of drug products between 0.1 and 113 ppm. The validated analytical procedure was applied in an investigation of approaches to mitigate nitrosamine formation in metformin drug products. The developed analytical procedures provide another tool for pharmaceutical manufacturers to evaluate drug products for nitrosamine impurities.

Peroxydisulfate Activation by Biochar from Banana Peel Promoted with Copper Phosphide for Bisphenol S Degradation in Aqueous Media

In this work, the decomposition of bisphenol S (BPS) by biochar derived from banana peel (BPB) promoted by copper phosphide (Cu3P) was examined. Different materials with Cu3P loadings from 0.25 to 4.00 wt.% on biochar were synthesized, characterized using the Brunauer–Emmett–Teller (BET) method, X-ray diffraction (XRD) and a scanning electron microscope (SEM) equipped with an energy dispersive spectrometer (EDS), and evaluated. Nearly all of the synthesized materials exhibited low to moderate adsorption capacity, attributable to their limited surface area (<3.1 m2/g). However, in the presence of sodium persulfate (SPS), the 2%Cu3P/ΒPB/SPS system was capable of removing 90% of 500 μg/L BPS in less than 10 min. The system’s performance was enhanced under inherent pH, and the reaction rate followed pseudo-first-order kinetics with respect to BPS and persulfate concentrations. Interestingly, the presence of 250 mg/L of sodium chloride had a negligible effect, while low to moderate inhibition was observed in the presence of bicarbonates and humic acid. In contrast, significant retardation was observed in experiments performed in real matrices, such as secondary effluent (WW) and bottled water (BW). According to scavenging experiments, both radical and non-radical mechanisms participated in the BPS degradation. Four transformation products were identified using the UHPLC/TOF-MS system in negative ionization mode, with two of them having higher molecular weights than BPS, while the other two TBPs involved the ring-opening reaction, and a BPS decomposition pathway was proposed.

Synergistic degradation of refractory organic pollutant by underwater bubbling plasma combined with heterogeneous Fenton process

Excessive discharge of the refractory organic pollutants endangers the development of the society and economy, thus seeking an efficient wastewater abatement method is an urgent need. Herein, Iron (Ⅱ) sulfide (FeS) was employed as the heterogeneous catalyst and coupled with underwater bubbling plasma (UBP) for the elimination of the refractory organic pollutant, malachite green (MG). FeS catalyst was synthesized using the solvothermal method and subsequently characterized comprehensively, focusing on its microstructure, specific surface area, chemical bonds and elements valence states. The UBP system combined with FeS (UBP/FeS) exhibited the robust synergism with a maximum synergistic factor of 1.89. The MG degradation percentage and rate constant were up to 94.7% and 0.237 min−1 within 12 min. The parameter experiments revealed that FeS dosage, pulse frequency, initial MG concentration and solution conductivity of 150 mg/L, 56 Hz, 5 mg/L and 21.8 μS/cm, respective, were more conducive for MG elimination. The MG removal efficiency reached 86.2% after five consecutive applications of FeS. Reactive substances including ·OH, ·O2−, eaq, O3 and H2O2 were confirmed to contribute to MG elimination. Additionally, the conversion circle between ≡ Fe(Ⅱ) and ≡ Fe(Ⅲ) promoted the catalytic conversion of H2O2 and O3 into ∙OH. The comparison of UV–vis spectra and total organic carbon of MG solution before and after reaction revealed the superior degradation of MG in the UBP/FeS system. Hypotheses regarding to the decomposition pathways of MG were formulated based on the identified intermediates. The toxicity level of MG solution was lightened after reaction. The above results indicate that UBP/FeS has the advantages of quick degradation and high efficiency, representing a promising approach for refractory pollutants treatment.

Study on pyrolysis process and mechanism of organic coating of waste polyesterimide enameled wire based on density functional theory

The pyrolysis treatment of waste polyesterimide enameled wire offers significant advantages such as continuous processing, non-hazardous nature, and high resource recovery rate. However, research on its pyrolysis process and mechanism remains insufficiently explored. In this study, techniques including thermogravimetry (TG), Fourier transform infrared spectroscopy(FT-IR), pyrolysis–gas chromatography-mass spectrometry(Py-GC/MS) were employed to investigate pyrolysis temperature, weight loss rate, pyrolysis and kinetic parameters, composition and distribution of pyrolysis products, and changes in functional groups under different temperatures and heating rates. The pyrolysis of polyesterimide enameled wire can be divided into three stages: volatilization of specific components (314.8 °C,1.6 %), rapid decomposition of polyesterimide (435.2 °C, 44.7 %), and generation of small organic molecules with the fixation of pyrolytic carbon (750 °C, 9.0 %). The main components of the pyrolysis gas products include aromatic compounds, ethers, aromatics, ketones, and carbon dioxide. At 400 °C, a substantial amount of pyrolysis gas products and free radicals are produced, with an increase in aromatic hydrocarbons. The carbon distribution in the pyrolysis products mainly focuses on C6-C10 and C11-C15, and many organic compounds such as benzoic acid, phenol, and aniline are generated. Based on density functional theory, the bond dissociation energies in the polyesterimide were calculated. This clarified the possible thermal decomposition pathways of the polyesterimide and provided the energy barrier values, elucidating the generation mechanism of pyrolysis products during thermal decomposition. The copper atom in specific location reduces the negative ESP of O and increases the positive ESP of H in EPI, which makes H more likely to attach to O. The presence of Cu increases the ESP range and promote the pyrolysis process. This study provides a theoretical basis for the high-value recycling of waste polyesterimide enamelled wire.

Recent Progress in Liquid Electrolytes for High‐Energy Lithium–Metal Batteries: From Molecular Engineering to Applications

AbstractLithium–metal batteries (LMBs) have garnered significant interests for their promising high gravimetric energy density (Eg) ∼ 750 Wh kg−1. However, the practical application of the LMBs is plagued by the high reactivity and large volume change during charging–discharging of the lithium–metal anode (LMA), seriously deteriorating the battery safety and cycle life. Great efforts have been devoted to tailoring the electrolytes to favor the Li–metal electroplating by uniformizing the deposition morphology and by suppressing the side reactions between electrolytes and LMA. The aggressive chemistries of both the LMA and its high‐voltage counterpart give new electrolyte components more opportunities, especially designing via molecular engineering. Here, a comprehensive and in‐depth overview of the scientific challenges, fundamental mechanisms, and particularly historical strategies of designing new molecules for electrolyte components including solvents, salts, and additives. Their important roles in tuning the Li+ solvation structure, interface composition, decomposition pathways, and the resultant electrochemical performance of LMBs are also presented. Finally, novel insights and promising research directions from the practical application viewpoints are proposed for future electrolyte designs for high‐voltage LMBs.

Study of the potential energy surface of reactions in a system containing <i>i</i>-propyl and <i>n</i>-propyl radicals

The energy pathways of possible decomposition and isomerization reactions of iso-propyl (i-C3H7) and n-propyl (n-C3H7) radicals have been studied by computational methods of quantum chemistry. B3LYP, M062X, MP2, and CBS-QB3 methods are used to localize stationary points on the potential energy surface of a system containing propyl radicals. A number of intermediate compounds formed during the isomerization and decomposition of propyl radicals have been identified, and information has been obtained on their structure and thermochemical parameters. Based on the results of the research, a diagram of the energy levels of the system under consideration was constructed.

Thermal Decomposition of 2-Cyclopentenone.

The thermal decomposition of 2-cyclopentenone, a cyclic oxygenated hydrocarbon that occurs in the pyrolysis of biomass, has been studied in a combined experimental and theoretical approach. Gas-phase pyrolysis was performed at temperatures ranging from 1000 to 1400 K in a pulsed, microtubular reactor. Products were identified by FTIR spectroscopy following their isolation in a low-temperature argon matrix. The following products were identified: carbon monoxide, ketene, propenylketene, vinylacetylene, ethylene, propene, acrolein, acetylene, propyne, and propargyl radical. Computational results identify three different decomposition channels involving a H atom migration, and producing prop-2-enylketene (Pathway 1), prop-1-enylketene (Pathway 2), and a second conformation of prop-2-enylketene (Pathway 3). A fourth decomposition pathway involves simultaneous rupture of two C-C bonds forming a high energy cyclopropenone intermediate that further reacts to form ethylene, acetylene, and carbon monoxide. Finally, a fifth pathway to the formation of acrolein and acetylene was identified that proceeds via a multistep mechanism, and an interconversion from 2-cyclopentenone to 3-cyclopentenone was identified computationally, but not observed experimentally.