Air Atmosphere Research Articles

Meso‐ and Microporous Metal–Organic Frameworks for Efficient Photo‐Oxidation of Benzylamine

ABSTRACTThe construction of metal–organic frameworks (MOFs) with desirable structures for high‐performance photocatalysis is attractive but remains challenging. Here, a hierarchically meso‐ and microporous scCu‐MOF‐74 was synthesized in supercritical CO2 (scCO2)/methanol solution. Compared with the conventional microporous Cu‐MOF‐74, the meso‐ and microporous scCu‐MOF‐74 has more exposed and accessible Lewis acid sites derived from the missing‐linker defects. The unique structure endows scCu‐MOF‐74 with superior molecular accessibility, enhanced separation, and transfer efficiency of photogenerated charges. High catalytic activity and reusability can be achieved in photo‐oxidative coupling of amines, reaching a maximum N‐benzylbenzaldimine yield rate of 4.80 mmol g−1 h−1 under mild conditions, that is, air atmosphere and room temperature. This study provides a new idea for improving the intrinsic photocatalytic activities of MOFs.

Numerical Simulation of the Ionic Composition and Ionization Phenomena in the Positive Column of a Millisecond DC-Pulsed Glow-Type Discharge in Atmospheric Pressure Air with a Water-Cathode

Numerical Simulation of the Ionic Composition and Ionization Phenomena in the Positive Column of a Millisecond DC-Pulsed Glow-Type Discharge in Atmospheric Pressure Air with a Water-Cathode

Attributable deaths in Austria due to ozone under different climate scenarios.

Tropospheric ozone is an air pollutant that poses a public health problem in Europe. Climate change could increase the formation of ozone. Applying past and predicted annual total (all-cause) mortality data and modeled daily ozone concentrations, we performed a nationwide health impact assessment estimating annual ozone-related (attributable) deaths in Austria. Different approaches were compared. Estimates were based on maximal 1-h averages of ozone. Until the decade from 2045 till 2055, more people will die in Austria because of the demographic trends. Therefore, more deaths will also be attributable to ozone. Higher greenhouse gas emission scenarios (e.g. Representative Concentration Pathway RCP8.5 compared to RCP2.6) will lead to more ozone-related deaths, mostly due to the national emission of ozone precursors (a difference of 250-340 cases per year, depending on the model), but to a lesser extent because of global climate change. Increases in attributable deaths will be affected mostly by national, not global mitigation measures. National emission reduction will certainly have a strong and beneficial effect on local atmospheric chemistry, air quality, and public health.

Development and Field Testing of Multi-Electrode Mixed Potential Electrochemical Sensors for Natural Gas-Hydrogen Mixture Emissions Monitoring

Transportation of hydrogen is one of the greatest hurdles to overcome in the development of a clean hydrogen economy [1]. A cost-effective solution to transportation of hydrogen is to mix it with natural gas (NG) and utilize current pipeline infrastructure for transportation [2]. However, hydrogen embrittlement, the higher diffusivity of H2, and the uncertain state of much of existing infrastructure makes leaks of H2 an environmental and safety concern. Current NG leak detection technologies largely use optical sensors such as IR spectrometers that are incapable of detecting H2 gas [3]. Mixed potential electrochemical sensors (MPES) are low-cost, robust devices capable of detecting a wide variety of gases [4], with the sensitivity and selectivity necessary for point source monitoring of natural gas leaks [5].Multi-electrode MPES devices using Indium Tin Oxide, Au, and La0.87Sr0.13CrO3 and Pt electrodes have previously successfully quantified CH4 in natural gas at the 10-40 ppm level [5]. In this work, we demonstrated that the Au vs. Pt electrode has a low limit of detection of < 3 ppm for H2 in an air atmosphere. We also performed field testing of H2 emissions at CSU’s Methane Emissions Technology Evaluation Center (METEC) in both underground and above-ground emissions of H2 and H2 + natural gas mixes (Figure 1) with successful detection of H2 at the ppm level. Finally, we evaluate the stability of the selectivity and sensitivity during prolonged exposure to H2 and CH4.This work was supported by US Department of Energy Award DE-FE0031864.

Comparison of collective acceleration of ions in a luce diode in residual atmospheres of air, argon and krypton

The paper compares the collective acceleration of ions in a Luce diode in residual atmospheres of air, argon and krypton at pressures of 6–156 mPa, evaluating the efficiency of capture of Ar and Kr ions into collective acceleration from their residual atmospheres. At a diode voltage of ∼232 kV, proton energies were 510 ± 38, 619 ± 62 and 567 ± 59 keV for air, argon, and krypton atmospheres, respectively, while the number of protons per shot was approximately 2 and 3 times higher in the argon and krypton residual atmosphere compared to the normal residual atmosphere. This increase in energy also led to a significant increase in the proportion of protons with energies greater than 3.02 MeV - to 1010 per shot on average. It was found that with increasing argon pressure, the diode current noticeably decreases, and with increasing krypton pressure, on the contrary, the diode current noticeably increases, which can be explained by the fact that argon is more neutral than krypton. The efficiency of capture of Ar and Kr ions into collective acceleration from their residual atmospheres was estimated as 0.06 % and 0.19 %, respectively.

Investigation of the effect of mass percentage concentration of polystyrene–toluene solution on the surface properties of the plasma‐treated polystyrene thin films

AbstractPolystyrene (PS) finds diverse applications across various fields, often necessitating a hydrophilic PS surface. In this study, the PS films were prepared using PS–toluene solutions of 15, 20, and 25 mass percentage concentrations (% w/v). Here, the main focus is on the influence of concentration on the hydrophilization of the prepared PS thin films under atmospheric pressure air dielectric barrier discharge plasma treatment. The contact angle, surface energy measurements, atomic force microscopy, and Fourier‐transform infrared spectroscopy analysis were conducted to evaluate the PS surface properties. Our results demonstrate, for the first time, the significant role of concentration in altering surface properties; the lower concentration of PS films leads to the most hydrophilic surface. Fourier‐transform infrared spectroscopy analysis confirms an increase in the OH functional group on the PS surface. atomic force microscopy analysis reveals needle‐shaped surface morphology, increased roughness and an expanded effective surface area. Surface energy analysis confirms an increase in the polar sector of surface energy. Overall, the findings from this research underscore the increase in film hydrophilicity with a decrease in PS–toluene concentration.Highlights Polystyrene (PS)–toluene solutions with different concentrations were prepared. PS–toluene films were spin‐coated and were been treated with dielectric barrier discharge plasma. The contact angle, surface energy measurements, atomic force microscopy, and Fourier‐transform infrared spectroscopy analysis were conducted. PS films with lower concentration have more impact from plasma treatment. Concentration, impact the hydrophilicity and roughness of treated PS films.

Electroless Deposition of Ni Nanoparticles on Boron Particles: Physicochemical and Oxidation Properties

Elemental boron also has a high volumetric heat of combustion (136 kJ/cm3), the third highest gravimetric heat of combustion (58.5 MJ/kg) and its oxidation is a highly exothermic process. All these features make boron an attractive constituent of propellants, explosives, and high energy density solid fuels for air-breathing propulsion as an energetic material. Given these uses, researchers have worked on the ignition and combustion processes of boron. However, boron has several serious issues that limit its practical use, including large ignition delay, inefficient combustion, and a complex burning process in solid propellants due to the formation of a defensive boron oxide (B2O3) layer on the boron surface. Previous studies have found that the ignition and combustion performance of boron can be improved by coating it with metal particles, metal oxides, or organic materials, as well as by removing the boron oxide layer.In the literature, there are limited studies on metal particle coating of a boron surface using the electroless Ni plating method. The electroless coating has several impressive advantages over conventional electrolytic coating. The prime advantage is that electroless plating does not require any electricity to operate and is a low-cost process. Among other advantages, it provides a uniform coating and can be used with all kinds of substrates with complex shapes. Conductive and non-conductive materials/powders can be coated with constant thickness with good adhesion.The present work investigated Ni nanoparticle coating on irregularly shaped/non-spherical boron particles using the electroless Ni-plating method at room temperature to prevent the oxidation of boron particles. This is preferable since it is very difficult to coat large quantities at relatively high temperatures. The four different simple paths were chosen during the electroless Ni plating to coat Ni on boron particles: no rinsing and no drying (Path A), only drying (Path B), both rinsing and drying (Path C) and only rinsing (Path D). Previous studies have explored the effect of bath concentration, pH, and temperature on the Ni coating. However, the influence of the four different paths mentioned above on Ni coating with boron particles or any other materials has rarely been investigated. Surface morphology confirmed the Ni nanoparticles coating on the surface of boron particles. The size of the Ni nanoparticles varied between 10 and 120 nm concerning the chosen paths used for preparation using TEM. XRD characterization results of the Ni coated boron particles showed the formation of crystalline Ni nanoparticles. EDAX and XPS results showed the presence of the primary B and Ni elements in samples synthesized in the present study. Thermogravimetric analysis conducted in air atmosphere found the boron particles coated with Ni nanoparticles had enhanced oxidation resistance compared to bare boron particles. Also, the Ni coated boron particles showed a shift in exothermic peak to a lower temperature and higher heat evolution than the bare boron particles.Acknowledgements:This work was supported by the National Research Foundation (NRF) of Korea grant funded by the Korea government (MSIT) No. 2019R1A2C1010862, 2022R1A2C2013508

Bidirectional Cascaded Superfluorescent Lasing in Air Enabled by Resonant Third Harmonic Photon Exchange from Nitrogen to Argon.

Cavity-free lasing in atmospheric air has stimulated intense research toward a fundamental understanding of underlying physical mechanisms. In this Letter, we identify a new mechanism-a third-harmonic photon mediated resonant energy transfer pathway leading to population inversion in argon via an initial three-photon excitation of nitrogen molecules irradiated by intense 261nm pulses-that enables bidirectional two-color cascaded lasing in atmospheric air. By making pump-probe measurements, we conclusively show that such cascaded lasing results from superfluorescence rather than amplified spontaneous emission. Such cascaded lasing with the capability of producing bidirectional multicolor coherent pulses opens additional possibilities for remote sensing applications.

Vertical Variability of Aerosol Pollution in St. Petersburg According to Long-term Lidar Observations

Processing of data obtained using lidar technologies was carried out to identify the vertical variability of the distribution of aerosols in the atmospheric column by month. The results of 227 lidar measurements from 2014 to 2023 were processed in total. It has been established that the concentration and height of compacted aerosol layers begin to increase in spring time, reaches a maximum in July, and from October there is a visible decline in aerosol concentrations in the atmospheric air. It has been established that in the warm season the height of compacted aerosol layers reaches 1200–1800 m, while in the cold season it reaches only heights of 600–1100 m. It was concluded that fine aerosol predominates over the city, based on the calculated Angstrom parameter in the range from 1.95 to 2.91.

Transformation of Cu2O into Metallic Copper within Matrix of Carboxylic Cation Exchangers: Synthesis and Thermogravimetric Studies of Novel Composite Materials.

In order to systematize and expand knowledge about copper-containing composite materials as hybrid ion exchangers, in this study, fine metallic copper particles were dispersed within the matrix of a carboxyl cation exchanger (CCE) with a macroporous and gel-type structure thanks to the reduction of Cu2O particles precipitated within the matrix earlier. It was possible to introduce as much as 22.0 wt% Cu0 into a gel-type polymeric carrier (G/H#Cu) when an ascorbic acid solution was used to act as a reducer of Cu2O and a reagent transforming the functional groups from Na+ into the H+ form. The extremely high shrinkage of the porous skeleton containing -COOH groups (in a wet and also dry state) and its limited affinity for water protected the copper from oxidation without the use of special conditions. When macroporous CCE was used as a host material, the composite material (M/H#Cu) contained 18.5 wt% Cu, and copper particles were identified inside the resin beads, but not on their surface where Cu2+ ions appeared during drying. Thermal analysis in an air atmosphere and under N2 showed that dispersing metallic copper within the resin matrix accelerated its decomposition in both media, whereby M/H#Cu decomposed faster than G/H#Cu. It was found that G/H#Cu contained 6.0% bounded water, less than M/H#Cu (7.5%), and that the solid residue after combustion of G/H#Cu and M/H#Cu was CuO (26.28% and 22.80%), while after pyrolysis the solid residue (39.35% and 26.23%) was a mixture of carbon (50%) and metallic copper (50%). The presented composite materials thanks to the antimicrobial, catalytic, reducing, deoxygenating and hydrophobic properties of metallic copper can be used for point-of-use and column water/wastewater treatment systems.

Fabrication of Micro‐Mesopores on Spiral Carbon Nanocoils and Simultaneous Doping with Oxygen to Expand Microwave Absorption Bandwidth

AbstractThe exceptional benefits of structural defects and doped atoms in carbon network regarding electromagnetic properties inspire the design of advanced carbon‐based microwave absorption (MA) materials. However, excessive structural defects decline the physical properties of materials, especially their conductivity. Therefore, it is a great challenge to balance structural defects and doped atoms to optimize conductive behavior for carbon‐based MA materials. The spiral carbon nanocoil (CNC), with coexisting amorphous and polycrystalline carbon structures and moderate conductivity, has significant MA properties but lacks pores and doped atoms. Herein, the amorphous carbon parts with relatively weak C─C bond energies are preferentially oxidized at 500 °C in air atmosphere to create pores and combine O atoms in the bodies of CNCs. Furthermore, the mechanism prioritizing the formation of O doping over defects is discovered. Benefiting from the synergistic interplay of structural defects and O dopants, the O‐enriched porous CNCs demonstrate enhanced conduction and polarization losses than the pure CNCs, realizing a wide effective absorption bandwidth of 7.3 GHz at a filling ratio of only 3 wt.%. Theoretical calculations further support these experimental results. The combination of structural defects and doped atoms may serve as an effective pathway for unlocking tunable dielectric properties of carbon‐based materials.

Influence of the atmosphere on the phosphorescence of a brominated diphenylphosphine oxide-ethyl naphthaleneimide dyad.

The molecular dyad diphenylphosphine-ethyl bromine naphthaleneimide (Br-DPPENI) emits strong fluorescence and phosphorescence. We studied the intensity and lifetime of the phosphorescence of Br-DPPENI embedded in PMMA films in atmospheres of air, He, Ar, N2, and O2 as a function of pressure between vacuum and ambient pressure (1 bar). The experiment was performed in the frequency domain with a two-channel lock-in amplifier, and the data were analyzed with the polar plot or phasor technique. Reversible shortening of the lifetime due to triplet-triplet annihilation was found in the presence of atmospheric or pure oxygen. With small modulation frequencies, an additional slow component of the phosphorescence dynamics is observed, which is ascribed to the diffusion of oxygen into the sample films.

High-Efficiency Photocatalytic Oxidation of Benzyl Alcohol by NH2-UiO-66-(Indole-2,3-Dione)-Fe.

The photocatalytic oxidation of biomass-derived benzyl alcohol provides a promising way for the synthesis of benzoic acid, which is an important intermediate with wide applications. To improve the efficiency of photocatalytic benzyl alcohol oxidation to benzoic acid is of great interest. In this work, we propose the utilization of NH2-UiO-66-ID-Fe catalyst for photocatalytic oxidation of benzyl alcohol to benzoic acid, where NH2-UiO-66 is a typically used metal-organic framework, ID is indole-2,3-dione (ID) that has biocompatibility, light absorption property and can be covalently combined with amino-functionalized substances. The NH2-UiO-66-ID-Fe catalyst exhibits improved light absorption and photo-generated electron-hole separation ability compared with NH2-UiO-66. The photocatalytic performance of NH2-UiO-66-ID-Fe was examined for the oxidation of bio-based benzyl alcohol under mild conditions of air atmosphere, room temperature and no additive or additional oxidant involved. The results show that the conversion of benzyl alcohol and the selectivity to benzoic acid could both reach over 99 % in 6 h, and the generation rate of benzoic acid per gram of catalyst is 3.36 mmol g-1 h-1. The reaction mechanism was detected by radical trapping method and in situ electron paramagnetic resonance. This study presents an efficient and environmentally benign avenue for the synthesis of carboxylic acid compounds.

Dynamics of a Discharge Initiated by a Powerful Femtosecond Laser Pulse in Atmospheric Pressure Air in Pre-Breakdown Electrical Fields

Numerical modeling of the dynamics of a discharge initiated by a high-power femtosecond laser pulse in air at atmospheric pressure in pre-breakdown fields was carried out. Calculations were conducted within the framework of a 1D-axisymmetric model that describes the evolution of the radial profiles of the main parameters of the discharge under study. The model includes a system of reaction that determine gas heating and a detailed description of the kinetic processes in a given discharge, as well as a system of gas-dynamic equations to describe the expansions of the heated channel. The results of calculations of the breakdown time of the discharge gap are conсistent with the measurement data over the entire studied range of electric field strengths, E = 9–17 kV/cm. It is shown that one of the key factors determining the evolution of the parameters of a given discharge is the rate of gas heating.

Environmental stability and ageing of ScN thin films from XPS Ar+ depth profiling

A basic knowledge on chemical stability and reactivity of a wide band gap ScN semiconductor in the presence of air atmosphere, where O2 and H2O represent the main degradation or corrosive agents, is of vital importance for a long-term performance of ScN-based devices for thermoelectric applications. Here, we present a systematic XPS Ar+ depth profiling analysis and optical and TEM characterizations of naturally room temperature air-aged thin ScN films prepared by a high-temperature DC sputtering on MgO(001) and SiO2 substrates. We find that superior crystalline quality ScN/MgO films degrade weakly after their quick initial surface oxidation and/or hydrolysis. Their oxidation is rather local and associated with the film-penetrating void-like interfaces. Significant initial surface oxidation and subsequent bulk oxidation after ageing is, however, observed for polycrystalline ScN/SiO2 films. Ab initio calculations of pure ScN and ScN with diluted nitrogen vacancies and/or substitutional oxygen impurities, which assist our experimental research, reveal pronounced impact of these defects on the ScN electronic structure. The modeled compositions reflect homogeneously and weakly oxidized films, while the real films correspond to relatively pure ScN crystallites with interfaces rich in oxygen.

Design and analysis of thermoacoustic air source heat pump water heaters

Thermoacoustic air-to-water air source heat pumps (TAWASHP) are the eco-friendly, simple, compressor less, low cost and likely looking future substitute for the existing compressor-based heat pumps. In this work, the design optimization of the 1-kW TAWASHP with helium for the temperature difference of 15 to 70 K for pumping heat from the atmospheric air to water using the linear thermoacoustic concepts was discussed. The optimized design can fit for both cooling and water heating applications without wasting the heat rejection to the surrounding atmosphere, rather supplied to the insulated hot water tank. The optimized one-fourth wavelength resonator TAWASHP shows the coefficient of performance of 1.1 to 2.34. The theoretical results are validated with the DeltaEC software results, and the results are in concurrence with each other. The DeltaEC predicts the TAWASHP can supply 1.55 to 3.35 kW of heat to water, which is equivalent to 37.3 to 80.3 kWh of heat energy per day.

Unraveling the nexus: exploring the interplay of mass media, personality traits and social norms in fostering protective behavior against smog

Purpose The rise in industrialization, economic development and urbanization has altered the composition of atmospheric air. Air pollutants have significantly impacted Pakistan's urban areas, resulting in the lowest air quality index readings. To understand disinclined behavior such as using air purifiers and wearing masks, this study aims to explore the relationship between individual personality traits and mass media effects. Design/methodology/approach This study used a cross-sectional survey with a model based on previous theories. Data from 2,000 adults were self-administered and analyzed using partial least squares structural equation modeling (PLS-SEM). Findings PLS-SEM confirmed six hypotheses, revealing mass media's direct and mediating roles in promoting critical psychological perceptions for protective behavior. The empirical results indicate that neuroticism, agreeableness and openness traits reinforce adherence behavior by intensifying threat perception. Practical implications This paper highlights significant implications for media campaign planners and provides more precise and comprehensive theoretical guidance. In the context of environmental challenges like smog, the findings illustrate how an understanding of personality traits can improve the efficacy of public health interventions through adherence to behaviors like mask-wearing and air purifier use. Addressing individual psychological characteristics when creating mass media campaigns to encourage public adherence to health protection measures related to environmental hazards. Originality/value Despite health campaigns and awareness, public compliance with measures like mask-wearing and air purifier use remains minimal. This study explores untapped mass media effects based on individual personality traits to understand this behavior.

Pyrolysis kinetics of waste ryegrass under nitrogen and air atmosphere

To investigate the pyrolysis reaction of ryegrass, we conducted a simultaneous thermal analysis using thermogravimetric(TG) analyzers. This involved obtaining data through Thermogravimetry (TG), Derivative Thermogravimetry (DTG), and Differential thermal analysis (DTA) techniques. The experiments were conducted under dynamic nitrogen and air atmospheres at different heating rates. The kinetic parameters of ryegrass pyrolysis were determined using the Kissinger method, the Flynn-Wall-Ozawa (FWO) peak conversion rate approximate equivalence method, the Flynn-Wall-Ozawa (FWO) equal conversion rate method, and the Škvára-Šesták (S–S) method. It provides a theoretical basis for the reuse of ryegrass resources. The findings indicated that the pyrolysis temperature of ryegrass increased with the accelerated rate of temperature increase in both atmospheres. The average weight loss rate of pyrolysis of ryegrass in the air atmosphere (92.27 %) is higher than that compared to that in a nitrogen atmosphere (86.11 %). Additionally, the temperature required for complete decomposition is lower in the former case. The FWO peak conversion rate approximation equivalence approach and the FWO equal conversion rate method do not apply to the solution of the pyrolysis activation energy of ryegrass. The pyrolysis activation energy for the two decomposition stages, as calculated by the Kissinger method, is 165.73 and 185.86 kJ/mol−1 in the air atmosphere, and 219.99 and 277.02 kJ/mol−1 in a nitrogen atmosphere, respectively. The activation energy and mechanism function of ryegrass pyrolysis calculated by using the S–S method are as follows: [−ln(1−α)]2, 119.79, 104.31, 95.75, and 91.93 kJ/mol−1 in air atmosphere, (1−α)−1, 176.64, 67.89, 61.15, and 54.25 kJ/mol−1 in nitrogen atmosphere, respectively. The activation energy of ryegrass pyrolysis, as determined by both the Kissinger method and S–S method, was found to be higher under an air atmosphere compared to a nitrogen atmosphere.

Impact of Relative Humidity on the Formation of Low-Frictional Interface and its Continuity in Tribological Systems with Hydrogenated Carbon Nitride Coatings

The impact of relative humidity on the formation of low-frictional interface in hydrogenated carbon nitride (CNx:H) coatings sliding against Si3N4 balls and the formation continuity was elucidated through friction tests conducted in both air and nitrogen atmospheres with controlled relative humidity levels. In air atmosphere, a carbonaceous tribolayer with a transformed structure from the initial CNx:H was formed on Si3N4 at less than the critical humidity that existed in 1.0–3.0% RH, resulting in low friction (μ < 0.05) and a low specific wear rate of the balls (< 2 × 10–9 mm3/N·m). In contrast, this tribolayer failed to form above 3.0% RH. In nitrogen atmosphere, within the 0.25–1.0% RH range, the tribolayer continued to form concurrently with wear progression, maintaining low friction for over 50,000 cycles. However, in less than this humidity range, the lifetime of low friction was limited owing to the tribolayer’s structural alteration. Thus, relative humidity influences not only the formation of the low-frictional interface but also the formation continuity. On the CNx:H friction surface, hydrogen, hydroxyl, and oxygen groups from environmental water and oxygen molecules continued to chemisorb owing to tribochemical reactions on the uppermost few nanometers during continuous low friction in a nitrogen atmosphere, while hydrogen content of CNx:H desorbed. This study experimentally confirmed the critical role of controlling relative humidity in tribological systems using CNx:H coatings to achieve low friction and improve its durability of low friction through the continuous formation of the low-frictional interface.

Pyrolysis mechanism of silicone rubber thermal protection system materials in service environment

The excellent oxidation and ablation resistance of silicone rubber thermal protection system (TPS) materials have made them extensively utilized in large-area thermal protection applications, such as ramjet engines and spacecraft reentry capsules, where air is present in the service environment. The ablation resistance is significantly influenced by the pyrolysis reactions, which serves as the foundation for subsequent ceramic transformation and the development of anti-erosion structures. The majority of previous research has been conducted in inert gas environments. To investigate the pyrolysis mechanism of silicone rubber TPS materials in realistic service environments, thermal analysis tests were performed using a range of analytical instruments including a thermal analyzer, mass spectrometer, infrared spectrometer, and X-ray photoelectron spectrometer from room temperature up to 1300 K in air atmosphere and compared with the results in argon atmosphere. The results demonstrate that silicone rubber TPS materials undergo both pyrolysis and oxidation reactions in air atmosphere. The primary pyrolysis of the matrix is attributed to cyclization reactions and side-chain cross-linking reactions. In comparison to argon atmosphere, the oxidation reaction produces a greater amount of organic gases, thereby diminishing the extent of cross-linking reaction and the thermal stability of the pyrolysis residue. The prolonged exposure to elevated temperatures allows for an extended duration of oxidation reactions, consequently diminishing the long-term thermal stability of TPS materials. The increase in mass of TPS materials at temperatures exceeding 1100 K can be attributed, in part, to the formation of new organic groups through oxidation reactions. The observed morphology of the residue, along with the weight gain from oxidation and SiO2 formation, promotes ceramic transformation of the materials at elevated temperatures.