Product Concentration Research Articles

Determination and Quantification of Acetaldehyde, Acetone, and Methanol in Hand Sanitizers Using Headspace GC/MS: Effect of Storage Time and Temperature.

Accurate determination of the concentration of alcohols and their metabolites is important in forensics and in several life science areas. A new headspace gas chromatography-mass spectrometry method has been developed to quantify alcohols and their oxidative products using isotope-labeled internal standards. The limit of detection (LOD) of the analytes in the developed method was 0.211 µg/mL for methanol, 0.158 µg/mL for ethanol, 0.157 µg/mL for isopropanol, 0.010 µg/mL for n-propanol, 0.157 µg/mL for acetone, and 0.209 µg/mL for acetaldehyde. The precision and accuracy of the method were evaluated, and the relative standard deviation percentages were found to be less than 3%. This work demonstrates the application of this method, specifically in quantifying the concentration of oxidative products of alcohol and other minor alcohols found in hand sanitizers, which have become an essential household item since the COVID-19 pandemic. Apart from the major components, the minor alcohols found in hand sanitizers include methanol, isopropanol, and n-propanol. The concentration range of these minor alcohols found in ethanol-based hand sanitizer samples was as follows: methanol, 0.000921-0.0151 mg/mL; isopropanol, 0.454-13.8 mg/mL; and n-propanol, 0.00474-0.152 mg/mL. In ethanol-based hand sanitizers, a significant amount of acetaldehyde (0.00623-0.231 mg/mL) was observed as an oxidation product, while in the isopropanol-based hand sanitizer, acetone (0.697 mg/mL) was observed as an oxidation product. The concentration of acetaldehyde in ethanol-based hand sanitizers significantly increased with storage time and temperature, whereas no such increase in acetone concentration was observed in isopropanol-based hand sanitizers with storage time and temperature. In two of the selected hand sanitizers, the acetaldehyde levels increased by almost 200% within a week when stored at room temperature. Additionally, exposing the hand sanitizers to a temperature of 45 °C for 24 h resulted in a 100% increase in acetaldehyde concentration. On the contrary, the acetone level remained constant upon the change in storage time and temperature.

Hydrogen-independent CO2 reduction dominates methanogenesis in five temperate lakes that differ in trophic states.

Emissions of microbially produced methane (CH4) from lake sediments are a major source of this potent greenhouse gas to the atmosphere. The rates of CH4 production and emission are believed to be influenced by electron acceptor distributions and organic carbon contents, which in turn are affected by anthropogenic inputs of nutrients leading to eutrophication. Here, we investigate how eutrophication influences the abundance and community structure of CH4 producing Archaea and methanogenesis pathways across time-resolved sedimentary records of five Swiss lakes with well-characterized trophic histories. Despite higher CH4 concentrations which suggest higher methanogenic activity in sediments of eutrophic lakes, abundances of methanogens were highest in oligotrophic lake sediments. Moreover, while the methanogenic community composition differed significantly at the lowest taxonomic levels (OTU), depending on whether sediment layers had been deposited under oligotrophic or eutrophic conditions, it showed no clear trend in relation to in situ distributions of electron acceptors. Remarkably, even though methanogenesis from CO2-reduction was the dominant pathway in all sediments based on carbon isotope fractionation values, taxonomic identities, and genomes of resident methanogens, CO2-reduction with hydrogen (H2) was thermodynamically unfavorable based on measured reactant and product concentrations. Instead, strong correlations between genomic abundances of CO2-reducing methanogens and anaerobic bacteria with potential for extracellular electron transfer suggest that methanogenic CO2-reduction in lake sediments is largely powered by direct electron transfer from syntrophic bacteria without involvement of H2 as an electron shuttle.

The Multidirectional Diaspora: Writing Chinese Migration History in a Time of Global Racial Reckoning

In On not speaking Chinese, cultural studies scholar Ien Ang characterizes migrant scholars as ‘tactical interventionists’; instead of making counter-hegemonic claims, they usually bring out the contradictions and the violence inherent in all posited truths. In the spirit of this claim, I thought long and hard about how to make the best use of my connections to both worlds – my lived experience of growing up in China and my access to academic resources in English-language academia. As James Gethyn Evans will show in his essay in this roundtable, ‘decolonizing’ the field of Chinese history should involve the dual tasks of questioning the hegemonic narratives propagated by the People’s Republic of China (PRC) government and the concentration of knowledge production in the Global North. Without the participation of PRC-based scholars, the current ‘decolonization’ movement would become a Western enterprise just like colonization.

Export product quality and inclusivity in developing countries

AbstractImproving the quality of export products is critical for promoting economic development, including for the achievement of sustainable development goals. The present study has examined the effect of export product quality improvement on inclusivity in developing countries. Inclusivity reflects a concomitant increase in the real per capita income, reduction in within‐country income inequality, and poverty reduction. The analysis covers 101 developing countries over the period from 1980 to 2014, and uses primarily the two‐step system Generalized Method of Moments estimator. It shows that export product quality improvement results in greater inclusivity, especially in countries that face high levels of economic growth volatility, including large magnitudes of external shocks. Likewise, export product quality improvement leads to greater inclusivity in countries that experience high levels of export product concentration. The analysis sheds light on the positive contribution of export product quality improvement to inclusivity in developing countries.

Biosynthesis of 10-Hydroxy-2-decenoic Acid through a One-Step Whole-Cell Catalysis.

10-Hydroxy-2-decenoic acid (10-HDA) is an important component of royal jelly, known for its antimicrobial, anti-inflammatory, blood pressure-lowering, and antiradiation effects. Currently, 10-HDA biosynthesis is limited by the substrate selectivity of acyl-coenzyme A dehydrogenase, which restricts the technique to a two-step process. This study aimed to develop an efficient and simplified method for synthesizing 10-HDA. In this study, ACOX from Candida tropicalis 1798, which catalyzes 10-hydroxydecanoyl coenzyme A desaturation for 10-HDA synthesis, was isolated and heterologously coexpressed with FadE, Macs, YdiI, and CYP in Escherichia coli/SK after knocking out FadB, FadJ, and FadR genes. The engineered E. coli/AKS strain achieved a 49.8% conversion of decanoic acid to 10-HDA. CYP expression was improved through ultraviolet mutagenesis and high-throughput screening, increased substrate conversion to 75.6%, and the synthesis of 10-HDA was increased to 0.628 g/L in 10 h. This is the highest conversion rate and product concentration achieved in the shortest time to date. This study provides a simple and efficient method for 10-HDA biosynthesis and offers an effective method for developing strains with high product yields.

Process systems engineering perspectives on eco-efficient downstream processing of volatile biochemicals from fermentation

Increasing concerns over environmental pollution, climate change and energy security are driving a necessary transition from fossil carbon sources to more sustainable alternatives. Due to lower environmental impact, biochemicals are rapidly gaining significance as a potential renewable solution, particularly of interest in Europe. In this context, process systems engineering (PSE) helps with the decision-making at multiple scales and levels, aiming for optimum use of (renewable) resources. Fermentation using waste biomass or industrial off-gases is a promising way for the production of these products. However, due to the inhibitory effects or low substrate concentrations, relatively low product concentrations can be obtained. Consequently, significant improvements in downstream processing are needed to increase the competitiveness of the overall bioprocesses. This paper supports sustainable development by providing new PSE perspectives on the purification of volatile bioproducts from dilute fermentation broths. Since purification significantly contributes to the total cost of biochemical production processes (20%–40% of the total cost), enhancing this part may substantially improve the competitiveness of the overall bioprocesses. The highly advanced downstream process offers the possibility of recovering high-purity products while enhancing the fermentation step by continuously removing inhibitory products, and recycling microorganisms with most of the present water. Besides higher productivity, the upstream process can be greatly improved by avoiding loss of biomass, enabling closed-loop operation and decreasing the need for fresh water. Applying heat pumping, heat integration and other methods of process intensification (PI) can drastically reduce energy requirements and CO2 emissions. Additionally, the opportunity to use renewable electricity instead of conventional fossil energy presents a significant step toward (green) electrification and decarbonization of the chemical industry.

Developmental programming of production and reproduction in dairy cows: III. Association of level of maternal milk production with offspring's birth weight, survival, productive and reproductive performance and AMH concentration from birth to the first lactation period

Although some studies investigated the relationship of dam milk production (DMP) with offspring birth weight and productive performance, limited information is available on the association of level of DMP with reproductive performance in dairy cows. Therefore, the present study was conducted to understand whether dams with various levels of milk production produce offspring with different fertility. In study I, offspring were classified based on the level of DMP into five categories, including DMP1 (dams with <10.00 × 103 kg of 305-day milk production), DMP2 (dams with ≥10.00 × 103 kg and <12.00 × 103 kg of 305-day milk production), DMP3 (dams with ≥12.00 × 103 kg and <14.00 × 103 kg of 305-day milk production), DMP4 (dams with ≥14.00 × 103 kg and <16.00 × 103 kg of 305-day milk production) and DMP5 (dams with ≥16.00 × 103 kg of 305-day milk production). In study I, data of birth weight, milk yield and reproductive variables of 14,536 offspring born to lactating dams and corresponding data of DMP were retrieved. In study II, blood samples (n = 339) were collected from offspring in various categories of DMP for measurement of serum AMH. Offspring were heavier at birth in DMP4 and DMP5 categories than DMP1 and DMP2 categories (P < 0.05). Milk yield of offspring increased as DMP elevated (P < 0.05); however, offspring in DMP1 and DMP2 categories produced higher milk as compared with their dams during primiparity (P < 0.05) whereas offspring in DMP3, DMP4 and DMP5 categories produced less milk as compared with their dams during primiparity (P < 0.05). Milk fat to protein ratio during the first month of lactation was greater in DMP4 and DMP5 categories than DMP1 category (P < 0.05). Offspring of DMP4 and DMP5 categories were inseminated and conceived at younger ages than offspring of DMP1 category during nulliparity (P < 0.05). Calving to conception interval was longer in DMP5 than DMP1 category in primiparous offspring (P < 0.05), but concentration of AMH did not differ among various categories of DMP (P > 0.05). In conclusion, dams with greater level of milk production produced heavier offspring with higher milk yield but worse transgenerational improvement in milk production and diminished reproductive performance, which were seemingly under higher pressure of negative energy balance during the first month of lactation.

Microscopic mechanism of carbon oxides formation during long-flame coal oxidation at molecular scale

Precursors of carbon oxides in coals are considered to be related to aldehyde group(–CHO) and carboxyl group (–COOH), but the way of decomposition of precursors to produce carbon oxides is not clear. Through theoretical analysis, experimental research and quantum chemical calculation at molecular scale, this paper explores the decomposition mode and products of carbon oxide precursors during coal spontaneous combustion (CSC). A programmed heating device was used to investigate the change rule of gas product concentration during the constant temperature oxidation of coals, and the microstructure of the coals was characterized by low-temperature nitrogen adsorption experiments (BET), X-ray Diffraction (XRD) and X-ray photoelectron spectrometer (XPS). The results of the study show that during coal oxidation, the inhomogeneous energy exchange between the coals and the external heat source results in the change of gas product concentration with time following two rules. BET experiments reveal that oxidation leads to the evolution of fine mesopores to macropores and an increase in the number of pores with diameters larger than 20 nm in the coals, which facilitates the transport of oxygen molecules through the pore structure. Within 200 °C, the microcrystalline structure of coals is basically unchanged, and the active structure C–C/C–H on the side chain is converted to –CHO and –COOH and then decomposed to produce carbon oxides. Quantum chemical calculation shows that the reaction energy barrier of carbonyl group and carboxyl group decomposed step by step to form carbon oxides is much smaller than that of direct decomposition, and carbon oxides and alkyl radicals can be produced even at room temperature by step decomposition. The research results provide theoretical guidance for the formation mechanism of carbon oxides during low temperature oxidation of coals.

ARTHRITIS GENE THERAPY: FROM CONCEPT TO CLINICAL TRIALS

Intra-articular injection is a common way to deliver biologics to joints, but their effectiveness is limited by rapid clearance from the joint space. This barrier can be overcome by genetically modifying cells within the joint such that they produce anti-arthritic gene products endogenously, thereby achieving sustained, therapeutic, intra-articular concentrations of the transgene products without re-dosing. A variety of non-viral and viral vectors have been subjected to preclinical testing to evaluate their suitability for delivering genes to joints. The first transfer of a gene to a human joint used an ex vivo protocol involving retrovirally transduced, autologous, synovial fibroblasts. Recent advances in vector technology allow in vivo delivery using adeno-associated virus (AAV). We have developed an AAV vector encoding the interleukin-1 receptor antagonist (AAV.IL-1Ra) for injection into joints with osteoarthritis (OA). It showed efficacy and safety in equine and rat models of OA, leading to a recently-completed, investigator-initiated, Phase I, dose-escalation clinical trial in 9 subjects with mid-stage OA of the knee (ClinicalTrials.gov Identifier: NCT02790723). Three cohorts of three subjects with mild to moderate OA in the index knee were injected intra-articularly under ultrasound guidance with a low (10e11 viral genomes) medium (10e12 viral genomes) or high (10e13 viral genomes) dose of AAV.IL-1Ra and followed for one year. The data confirm safety, with evidence of sustained intra-articular expression of IL-1Ra and a clinical response in certain subjects. Funding for a subsequent Phase Ib trial involving 50 subjects (ClinicalTrials.gov Identifier: NCT05835895), expected to start later this year, has been acquired. Progress in this area has stimulated commercial activity and there are now at least seven different companies developing gene therapies for OA and a number of clinical trials are in progress.Acknowledgement: Clinical trial funded by US Department of Defense Clinical Trial Award W81XWH-16-1-0540.

Territorial concentration of the production of electrical machines in the branch policy of the Soviet government in the first half of the 1920s and Ukrainian electrical machine building industry: historiography and reality

In the Soviet territories of the former Russian Empire in the early 1920s, an attempt was made to carry out global concentration of production - the geographical concentration of production not of any range of a particular type of product, but of its entire volume. That is, the concentration of the type of industrial activity as such was assumed, the possibility of it in socialist society was justified by K. Marx. Due to objective and subjective factors, the only industry where such an attempt became possible was electrical machine-building, and during 1920�1923. the production of electric machines began to concentrate in Moscow and Petrograd, which undermined the potential of Ukrainian electric machine branch. Considering the political importance for the Soviet government of neutralizing this negative, the concentration of electrical machine-building activities in Soviet capitals from 1925 began to be presented as a result of the industrial policy of Tsarist Russia, what moved into historical works. However, the information available in the documents completely refutes this view, while simultaneously confirming the purposeful actions of the Soviet government to curtail the electrical machine industry in Ukraine.

Multi-physical field simulation calculation and analysis of simulated high-level waste liquid spray calcination.

Aiming at the independent research and development of a simulated high-level waste liquid spray calcination transformation treatment test device, a three-dimensional multi-physical field model of spray calcination was established by means of finite element analysis method. In this paper, the simulated high-level waste liquid is a mixed solution of nitrate solution and sucrose. The main chemical components of nitrate dissolution are HNO3 and NaNO3. The process of evaporation and calcination of high-level waste liquid to form oxides is also called the pretreatment of high-level waste liquid or the conversion of high-level waste liquid. In this experiment, the atomized droplets sprayed at high speed are evaporated, dried and calcined in turn in the calciner to obtain the calcined product. The distribution law of temperature flow field and chemical reaction state and results inside the test device were revealed by simulation calculation. The results show that under the condition of multi-physical field coupling, the chemical reaction temperature has an effect on the yield of the product. The temperature is positively correlated with the product concentration, and the effect of temperature on the yield of NO2 is greater than that of Na2O. At the same time, in this chemical reaction, the concentration of reactants (NaNO3 and HNO3) had a positive correlation with the concentration of main products (NO2 and Na2O). However, the rate of increase in the concentration of the main products (NO2 and Na2O) decreased with the increase of the concentration of the reactants (NaNO3 and HNO3).

Радиационная обстановка в районе горного массива Бештау

The article presents the outcomes of the dead uranium mine inspection and its impact on the current radiation situation in the Beshtau area, as well as radiation doses to the people using the area as a recreation land. The Beshtau mounting uranium mine was in use from 1940s to 1990s. Several stages of the site remediation were conducted since the 1990s. For these purposes gamma dose rates, density of radon flux from ground surface and its products concentration in the atmospheric air, the content of natural radionuclides in the ground and groundwater were estimated. According to the measurements data it is seen that the area around the main mine facilities located in the southwestern and southern parts of the Beshtau mounting, is the mostly susceptible to radioactive contamination. The water from the springs in this area is not suitable for drinking because the levels of uranium and radon in the water exceed the control safe limits. According to radiation dose estimates in the considered area, it becomes evident that the radiation risk in the area depends mainly on the presence of the gas flows from the tunnel, radiation risk can be higher if the gas flow is not fully extinguished. The tunnels mouths in the study area are not completely extinguished, and the mine air is periodically blown out of them. Due to the current situation, the levels of radon and gamma radiation around the adit mouths exceed the permitted safe limits. If people stay in this area for 4 hours, they can receive radiation dose above 1.0 millisievert (mSv), that exceeds the recommended safe limit. In this regard, it would be advisable to implement measures to prevent or reduce the time people spend in the areas where the former tunnels mouths are located.

Pharmaceutical products, drugs and personal care products in European waters: A protocol for systematic review and meta-analysis.

This study aims to describe a protocol for a systematic review and meta-analysis that assesses the detection and concentration of pharmaceutical products, drugs, and personal care products in European waters. This study protocol was developed following the recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA-P) statement and the Cochrane Handbook of Systematic Reviews of Interventions. We will include studies conducted on European waters of various origins (watersheds, aquifers, rivers, seas, springs, wastewaters, and drinking water). A comprehensive search strategy will be implemented in the following databases: PubMed (Medline), EMBASE, Scopus, and Web of Science. Two independent reviewers will conduct all study selection procedures, data extraction, and methodological evaluation. Any disagreements will be referred to a third reviewer. If the studies are sufficiently homogeneous, we will conduct a meta-analysis to summarize the data. We will use the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) to assess the certainty of the evidence. The systematic review and meta-analysis will provide valuable information about the presence and concentration of these types of contaminants in water, aiding in the development of public policies regarding prevention and decontamination measures to enhancing water quality in Europe.

Heoretical Analysis of Amperometric Biosensor with Substrate and Product Inhibition Involving non - Michaelis - Menten Kinetics

In this paper, a non-steady-state amperometric biosensor with the mixed enzyme kinetics and diffusion limitations under the inhibitions of substrate and product is modeled mathematically. The non-steady-state reaction-diffusion equations of the system consist non-linear terms related to an enzymatic reaction of non-Michaelis-Menten kinetics. We have presented the approximate analytical solutions for the concentrations of substrate and product in non-steady and steady-state models using the new approach of Homotopy perturbation method (HPM). The provided expression is presented for all potential diffusion and kinetic parameter values. Analytical expressions of the biosensor current and sensitivity are also presented and discussed. In addition, we also provided numerical solutions for the proposed model by utilizing the pdepe tool in MATLAB software. When comparing the analytical solution with the numerical solution, a satisfactory result is noted for all the possible values of the parameters. Furthermore, the influence of diffusion and kinetic parameters on both the current and the sensitivity are discussed. Analytical expressions for the limiting cases of biosensor enzyme kinetics are presented in this research article. Additionally, an analytical expression for determining the effective thickness of the membrane is derived and presented.

Оптимальный выбор начальных условий задачи Коши и его применение для расчета начального состава реакционной смеси

The article is devoted to the development of a numerical algorithm for optimal selection of initial conditions of the Cauchy problem and its application to the problem of optimal selection of initial concentrations of substances in a chemical reaction. In general form, the problem of determining the optimal composition of the reaction mixture is formulated based on the kinetic model of the reaction. A step-by-step algorithm has been developed to solve the problem using the penalty method and the Hooke-Jeeves method. The advantage of the algorithm is that it takes into account the physical and chemical features of the problem. Based on the formulated algorithm, a software package has been developed for the catalytic reaction of the synthesis of N-(adamantyl)acetamide. With its help, the optimal concentrations of the reaction reagents were calculated, at which the highest concentration of the target product is achieved.

A multi-indicator prediction method for NOx emission concentration and ammonia escape value for cement calciner system

It is particularly important to accurately predict NOx emission concentration in cement production. As the cement industry is a process industry, there are many chemical reactions, coupling of front and back processes, and large fluctuations in production, resulting in time-delayed denitration data, strong coupling, and uncertainty, which makes it difficult to adequately extract the characteristics of the denitration data to achieve accurate prediction of NOx concentration. At the same time, excessive ammonia is used in production to reduce NOx concentration, resulting in increased ammonia escape and secondary hazards to the environment, therefore it is necessary to perform accurate multi-step prediction of NOx concentration and ammonia escape. To address these issues, this paper presented a new multicriteria deep learning hybrid model MI-ITBA. The model is constructed by connecting an improved causal dilated temporal convolutional network (ITCN) with bidirectional gated recurrent units (BiGRU) and a special attention mechanism, which enhances the ability to extract features from denitration sequence, using the attention mechanism to weigh the importance of different time steps and highlight the influence of key features on the prediction results. In addition, the time series (TS) of denitration containing time-delay information is designed in the input of the model to minimize the influence of time delay. Dynamic information support for denitration control was provided by multi-step prediction of NOx concentration at seven moments and ammonia escape value at three moments to retain the dynamics of the data. Compared with TCN, BiGRU, and TCN-BiGRU, MI-ITBA has a high prediction accuracy, which can provide an effective guide to realizing NOx emission reduction and accurate ammonia injection.

Analysis of the concentration and monopolization of production in the economy of the regions

Analysis of the concentration and monopolization of production in the economy of the regions

Pollutants and Their Potential Toxicity in the Water Bodies of the "Oleksandriya" Arboretum (Ukraine)

The levels of contamination of the water bodies of the "Oleksandriya" arboretum (the town of Bila Tserkva, Ukraine) by heavy metals, petroleum products, and anionic synthetic surfactants were investigated in August 2022 and their potential toxicity for aquatic organisms was assessed. It has been proven that the detected concentrations of some heavy metals (Cu, Zn, Mn, Fe, and Pb) in the ponds located in the Western ravine of the "Oleksandriya" arboretum can exert an adverse effect on the vital activity of hydrobionts (aquatic plants, fish, etc.). The maximum concentration of petroleum products was registered in the water of the Kholodny pond (the Eastern ravine of the park), which can cause toxic effects in hydrobionts. The water of the ponds also contained anionic synthetic surfactants probably due to the influx of municipal sewage, which also results in worsening the ecological and toxicological state of the studied water bodies.

In vivo comparison of antioxidant properties of fucoidan from Fucus vesiculosus after intragastric administration and external application

Fucoidans are sulfated heteropolysaccharides from brown seaweed, known for anticoagulant, anti- inflammatory, antiviral and other properties. The method of administration and the dosage form of the medicinal substance have a significant impact on the bioavailability of the drug, as well as on its metabolism in the body.The purpose of the work was to evaluate the effect of fucoidan from Fucus vesiculosus on the indicators of the antioxidant system in mice with experimental streptozotocin-induced diabetes when administered intragastrically and externally.To evaluate the antioxidant properties of fucoidan in vivo , diabetes mellitus was developed in mice by intraperitoneal administration of streptozotocin and a 1% solution of nicotinic acid. Fucoidan in two dosage forms was administered for 10 days after the formation of the pathology at a dose of 50 mg/kg in the form of tablets intragastrically and 10 mg per animal in the form of an ointment when applied externally. To assess the antioxidant status of animals, the concentration of thiobarbituric acid-reactive products (TBA-RP) in the blood plasma, the level of reduced glutathione (GSH) and catalase activity (CAT) in the erythrocytes were determined.In mice with streptozotocin-induced diabetes against the background of pathology, the process of lipid peroxidation intensified and the effectiveness of the antioxidant system decreased. Fucoidan from F. vesiculosus suppresses systemic oxidative stress in mice with induced type 2 diabetes mellitus. This is achieved due to the inhibition of excessive generation of pro-oxidants (TBA-RP) and a protective effect on the factors of the antioxidant defense system (catalase activity and glutathione content). To the greatest extent, fucoidan, when administered intragastrically, prevents the formation of pro-oxidants, while when applied externally, it has a protective effect to a greater extent due to the activation of antioxidants.

Dual oxidant and reactant interactions in NEPE pyrolysis: Experimental and kinetic modelling insights

The reaction of dual oxidants (NO2 and O2) and dual reactants (NH3 and CH2O) obtained from the pyrolysis of NEPE was investigated both experimentally and numerically. Experiments were performed in JSR at atmospheric pressure, at low and medium temperatures of 600–1000 K, with equivalence ratios of 0.67–1.33, and the species concentrations of reactants, intermediates, and products were measured. A detailed kinetic model was then developed, which can capture the experimental results. The kinetic analysis revealed that NO2 was the main oxidant at low temperatures, as the temperature increased, O2 became more competitive, reducing the flux of the NO2 consumption pathway. Additionally, NO shows a non-monotonic trend with increasing temperature. On the one hand, this is due to the competition between O2 and NO2, which leads to a decrease in the flux of NOx formation. On the one hand, at higher temperature, HCO tended to decompose to produce H, which converted NO2 to NO by the reaction NO2 + H = NO + OH, increasing the fluxes of NH2 and NO and leading to an increase in DeNOx pathway flux. Furthermore, the O2 concentration directly affected the activity of the reaction system. This is because O2 accelerates the reaction NO + HO2 = NO2 + OH through HO2 generated by the reaction HCO + O2 = CO + HO2, and this pathway not only replenishes NO2 but also provides a large amount of OH.