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This study elucidates the impact of the types and blending ratios of low-carbon alkanes (methane and ethane, C1/C2) on the combustion and emission performance of NH₃ and analyzes the reasons for the differences in the effects of C1/C2 from the elementary reaction. The experimental and numerical analysis results show that C1/C2 reduces the temperature dependence of NH₃ oxidation and promotes the formation of combustion-promoting (CP) radicals. The concentration of CP is determined by the strength of the H-abstraction reactions of C1/C2. The initial H-abstraction product of C1, CH₃, exhibits reaction inertness, whereas the inert radicals of C2 (C₂H₄, C₂H₃, and C₂H₂) appear after three main H-abstraction steps. Additionally, C1/C2 intensifies the NH→N→NO reaction, worsening thermal-NO emissions; this study classifies it as a thermal-NO generation pathway. Although NH₂ and NH significantly reduce fuel-NO, their effect on thermal-NO is less pronounced. The consumption of thermal-NO primarily depends on the reverse direction of the reaction N 2 +O N + NO. • The introduction of C1/C2 reduces the temperature dependence of NH 3 oxidation reactions. • The dehydrogenation reactions of C1/C2 produce different types of inert radicals that limit subsequent dehydrogenation reactions. • C1's inert radicals form after the first dehydrogenation, while C2's form after the third dehydrogenation. • For the HC(O)/NH 3 , NH.→N→NO should be classified as one of the thermal-NO generation pathways. • Thermal-NO consumption depends on N accumulation, driving the reaction N 2 +O=N+NO. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Xi'an Jiaotong University is the property of Editorial Office of Journal of Xi'an Jiaotong University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At present, the selection criteria and configuration methods for fireproof clapboards in cable tunnels are not yet perfect, making it difficult to achieve effective fire protection. Therefore, an equivalent fire condition testing method is proposed to analyze the fire-resistant property of fireproof clapboards of different materials. Firstly, a tunnel fire experiment platform was built to carry out the combustion experiment of the high-voltage cable intermediate joint. The cable combustion equivalent fire source device is developed based on the temperature rise characteristics under different combustion conditions. However, the temperature rise characteristics of the equivalent fire source and the actual cable combustion error are within 10%. Then, four typical fireproof clapboards were tested under equivalent fire sources. The results indicate that the organic molded board has the best performance. In addition, factors such as the thickness, side panel height, and installation method of the fireproof clapboards were tested and analyzed. The results indicate that a minimum thickness of 5 mm for the fireproof clapboard and a height of 200 mm for the side panel of the clapboard are necessary to ensure effective protection. The installation method of hoisting fireproof clapboards can effectively extend the protection time by about 30% compared to the flat method. [ABSTRACT FROM AUTHOR]

With the development of control technology, the uniflow scavenging opposed-piston (USOP) diesel engine has shown unique advantages in energy savings and emission reductions. Due to the uniflow scavenging process, unstable scavenging performance has become the key problem in the development process of the USOP diesel engine, and the intake structure is an effective method for regulating scavenging performance. This study verifies the simulation model based on experimental data and then analyzes the influence of the intake port structure through simulations. On the one hand, this study explores the interference mechanism and application rules of two structures: composite intake ports and dual independent intake ports. The results show that the external alignment structure should be used under all operating conditions for composite intake ports. For dual independent intake ports, the internal alignment structure should be used at high swirl strength, and the external alignment structure should be used at low swirl strength. On the other hand, the dual independent intake ports matching the dual intake channels can improve scavenging performance while reducing supply power. The conclusion provides a reference for the design of the intake structure of the USOP diesel engine from many aspects. [ABSTRACT FROM AUTHOR]

In this paper, ammonium perchlorate (AP) as a strong oxidant has been added into Al/polyvinylidene difluoride (PVDF) nanothermites. Based on homogeneous structure of PVDF, shorter reaction contact between components can be obtained for more outstanding ignition and combustion performance. Water contact angle experiments were conducted to evaluate the hydrophobicity of the composite films, indicating that the suitability of composite material has enhanced under wet environment. According to TG-DSC results, the thermal decomposition of AP can improve the whole heat release process, which theoretically has excellent combustion performance advantages. Constant volume pressure tests were conducted to assess the energy release properties of the films compared with Al@PVDF films. Combustion performance in air was evaluated by employing optical sensors and a high-speed camera to measure factors such as the ignition delay time, light intensity and combustion flame propagation. After adding 15 % AP, the maximum pressure of Al/AP@PVDF film is 0.0960 Mpa, and that of Al@PVDF film is 0.0805 Mpa. The maximum pressure of the film is increased by nearly 19.25 %. Compared with Al@PVDF film, the ignition delay time of Al/AP@PVDF film is shortened by 45 ms, and the light intensity is increased by nearly 93.39 %. However, excessive AP content adversely impacted film formation efficiency, leading to the deterioration of various properties. Therefore, an optimal AP content of approximately 15 % in Al/AP@PVDF system was finally identified. [ABSTRACT FROM AUTHOR]

The experiment carried out halogen-free flame retardant modification treatment on polyethylene-based wood-plastic composite materials. The results showed that after adding flame retardant, the ignition time of the material increased to 76 seconds, an increase of 22 seconds. At combustion temperatures above 530°C, only a small amount of the material's residue continues to evaporate. When the temperature rises to 800°C, the difference in the residual carbon content of the samples gradually becomes larger. The residual carbon content of sample 1# is only 10.1%. At this time, the residual carbon content of samples 7#, 8# and 9# are respectively Reaching 27.12%, 27.09% and 25.60%. The above results show that the thermal stability of composite materials has been greatly improved after adding nano-flame retardants, providing new ideas and methods for the application of flame retardant and halogen-free flame retardant materials of wood-plastic composites. [ABSTRACT FROM AUTHOR]

Molecular perovskite energetic material DAP-4 was synthesized by chemical methods, and it was characterized by using SEM, EDS, XRD, IR, XPS, and elemental analysis. The enthalpy of formation (AHf) and the thermal decomposition per¬formance of DAP-4 were tested by using the oxygen bomb calorimeter and DSC technology. Its mechanical sensitivity, detona¬tion performance, and combustion performance were also carried out. The DAP-4 was used in CMDB propellant, and the con¬stant volume combustion and the constant pressure combustion performance were tested. The results show that the enthalpy of formation of DAP-4 was determined as 278. 6kJ/mol. At a heating rate of 20 °C /min, the peak temperature of thermal de-composition reached 392. 5 °C, the activation energy of thermal decomposition (fK) was 247. 2kJ/mol, and the critical tem¬perature of thermal explosion ( Tb) reached 631. 6K, which was much higher than that of HMX. The impact sensitivity of DAP-4 was similar to that of TNT, and the friction sensitivity was closed to CL-20. The detonation velocity of DAP-4 was as high as that of RDX. The chemical energy storage, work capacity, and metal acceleration ability of DAP-4 and its mixed explo¬sives were significantly higher than those of RDX and HMX, which was closed to CL-20. The constant volume combustion ex¬periment showed that the CMDB-1 propellant containing DAP-4 had the fastest burning rate, the highest combustion pressure, and the highest pressurization rate. The constant pressure combustion data showed that the combustion temperature of CMDB-1 propellant was the highest, which can reach 3 501 °C . [ABSTRACT FROM AUTHOR]

In this paper, we investigated the potential use of a new organic-inorganic hybrid crystal structure based on KNO3 in ignition compositions. H2dabco[K(NO3)3] (DAN-2) with organic-inorganic hybrid crystal structure is synthesized through intermolecular assembly technology. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) were used to detect the crystal morphology, structure and molecular structure of DAN-2, which has a regular cubic structure. Experimental data were obtained using thermogravimetric/differential scanning calorimetry (TG-DSC), closed bomb test and high-speed photography, which were then used to study and analyze the thermal decomposition properties and combustion properties of DAN-2. The initial thermal decomposition temperature of DAN-2 was low (194 °C) and the activation energy of the thermal decomposition was 154 kJ/mol. Possible thermal decomposition mechanisms are further discussed and proposed. This research pushed forward the application of organic-inorganic hybrid crystal structure oxidant DAN-2 in ignition system.

Microscale energetic materials have garnered considerable attention because they can be integrated in microelectromechanical systems for several potential applications. Hexanitrostilbene (HNS) has been widely utilized in ignition and initiation devices owing to its excellent thermal and shock stability and high sensitivity to short pulse shock waves. To meet the energy release requirements of micro-detonation devices, HNS sticks were prepared using direct ink writing and their reaction and flame propagation properties were studied. HNS particles sized 17.5 µm to 5 µm and ∼500 nm was prepared. Then, the viscosity of HNS-based inks prepared via acoustic resonance technology decreased when the particle size decreased or when the HNS content reduced from 97 wt.%, 95 wt.%, and 92 wt.%, to 90 wt.%. Additionally, the HNS-based inks with different binders exhibited different viscosity. The effect of the inner diameter of needle (0.4 mm, 0.6 mm, and 0.9 mm), printing rate (13 mm/s, 15 mm/s, 17 mm/s, 19 mm/s), and pressure (0.05 MPa, 0.1 MPa, 0.15 MPa, 0.2 MPa) on the width of HNS sticks was also elucidated. HNS-based sticks with a diameter of 0.9 mm underwent self-sustaining combustion reactions, and the burning rate increased from 5.1 mm/s to 6.8 mm/s as the particle size decreased from 17.5 µm to 500 nm. Overall, this work provides an effective approach to prepare microscale HNS for integration into micro-energetic devices.

The types of solid fires are diverse and the suppression highly depends on the adhesion and surface cooling effects of the extinguishing agent. In order to overcome the disadvantage of low adhesion and improve the efficiency of water in suppressing fires, a novel environmental-friendly thermal gelation hydrogel was prepared with hydroxypropyl methylcellulose (HPMC), sodium n-dodecyl sulfate (SDS), and super absorption resin (SAR) as the main raw materials. Ammonium polyphosphate (APP) and aluminum hydroxide (ATH) were added to enhance the fire-suppressive properties of the hydrogel. Then, cone calorimetry experiments were carried out to investigate the suppression effects differences between the hydrogels and water. According to response surface methodology, the optimal composition of hydrogel is the amount of HPMC, SDS, and SAR was 1.28 wt%, 1.50 mM, and 0.20 wt%, respectively. By adding APP and ATH flame retardants in combination, the hydrogel exhibited a reduced gelation temperature and an improvement in viscoelasticity, making it more effective in suppressing fires. Compared with water, solid fuel samples covered with hydrogel presented longer time to ignition. The maximum heat release rate was reduced by 53.27 kW/m2 and total smoke production exhibited a reduction of 12.23%. The hydrogel generated a fireproof and dense char layer on the solid surface, which acted as a barrier against heat and mass exchange, effectively suppressing the development of fire. The results of this study can provide guidance for the development of hydrogel extinguishing agents. [ABSTRACT FROM AUTHOR]

In order to improve the dilution combustion performance of methanol engines and clarify the influence of methanol direct double injection parameters on engine performance in the case of different DMG (dissociated methanol gas) blending ratios, this study will analyze the effects of the coupling application of DMG and methanol direct double injection on the engine dilution combustion performance by the traditional method and the Taguchi method. By the traditional method, it is concluded that increasing the DMG blending ratio, delaying the first injection timing, and decreasing the second injection ratio can lead to the advance of CA10, CA50, and CA90 (crank angle corresponding of 10%, 50% and CA90 heat release), the decrease of CO (carbon monoxide) and HC (hydrocarbons) emissions, and the increase of NOx (nitrogen oxides) emissions, while adjusting the second injection timing will have little effect on engine performance. By the Taguchi method, the optimal combinations of double injection parameters are A1B1C1, A1B2C1, and A1B2C1 when the DMG blending ratio is 0%, 7.5% and 15%, respectively. When the DMG blending ratio is 15%, and the injection strategy is a double injection, the dilution combustion limit is extended from 1.4 to 1.75 compared to the original operating condition. [Display omitted] • Effect of single injection control parameter on engine performance. • Optimization of injection control parameters for combustion performance. • Effect of blending DMG and injection strategy on engine performance. • The dilution limit is extended from 1.4 to 1.75 by two technologies. [ABSTRACT FROM AUTHOR]

This study investigated the combustion characteristics of mixed straw char and coal powder when used in blast furnace injection. The experiments examined the effects of mixing ratios between biomass char types of wheat straw char, corn straw char as well as cotton straw char, and anthracite coal on combustion characteristics and the injection effect of blast furnace. The results show that a 1:1 mixing ratio of wheat straw char and anthracite coal yields the best combustion characteristics, followed by a 1:1 ratio of corn straw char and anthracite coal. A 2:1 mixture of cotton straw char and anthracite coal exhibits the highest combustion efficiency. The study on the grindability of the mixtures indicates that straw char is easier to grind due to its brittleness. Blast furnace coal injection experiments reveal that a 50:50 mixture of cotton straw char and anthracite coal achieves the highest combustion efficiency at 74%, which is a 20.2% improvement compared to mixtures of bituminous coal and anthracite coal, significantly outperforming the other ratios. The findings underscore the importance of integrating renewable biomass resources in industrial applications to enhance sustainability in the metallurgical industry. [ABSTRACT FROM AUTHOR]

In order to explore the combustion performance of a non-road air-cooled two-cylinder turbocharged diesel engine, an experiment on the effects of engine compression ratio, combustion chamber shape and injection timing were systematically conducted in this study. Moreover, the effects of intake air conditions on combustion performance were numerically investigated using the one-dimensional simulation platform. The findings of this study could help provide new insights for promoting the sustainable development of diesel engines used in generator sets. The results show that the increase in intake air temperature can delay the combustion center of gravity and improve the combustion performance and the sustainability of diesel engines. The decrease in intake air pressure leads to a reduction in oxygen amount during the combustion process, thus causing the deterioration of cylinder pressure and combustion performance. By modifying the combustion chamber, the ignition delay and combustion duration are each extended by 1.6 degrees and 4.2 degrees under 100% engine load. The ignition delay and combustion duration are not obviously affected by modifying the combustion chamber shape under 25% and 50% loads. By increasing the compression ratio from 19.5 to 20.5, the ignition delay and combustion duration are shortened, which could enhance the cylinder pressure and heat release rate. However, reducing the compression ratio from 19.5 to 18.5 could significantly decrease the heat release rate. Under middle and low loads, combustion duration is less affected by injection timing. Under 100% load, the peak cylinder pressure increases to 11.4 MPa, and the ignition delay is shortened by advancing injection timing from −17 °CA to −20 °CA. [ABSTRACT FROM AUTHOR]

Timber is the most widely used material for furniture in view of its characteristics of light mass, high strength, easy processing, coloring, and decorative appearance. However, the flammability of wood has been frequently associated with increased fire intensity and the rapid spread of fire in buildings. In this paper, the combustion performance of six kinds of common furniture timber was investigated based on thermogravimetric analysis at 25–500 °C, cone calorimetry with 50 kW/m2 thermal radiation intensity, and flame spread experiments with 3 kW/m2 thermal radiation intensity. The ignition, weight loss, thermogenesis, smoke, and flame spread characteristics of these timbers were obtained. Subsequently, a comprehensive index system including thermal stability, heat release ability, smoke production capacity, and flame spreading speed was constructed to evaluate the combustion performance of the selected timbers. In addition, a grey correlation method relying on the game theory to assign weight was proposed for the quantitative analysis of the relevant evaluation indexes. As a result, the combustion performance of the six kinds of timber, which was defined as a specific value from poor to good, was as follows: pine (0.8696) > Chinese fir (0.8568) > Oriented Strandboard (OSB) (0.8425) > density board (0.8122) > plywood (0.8087) > elm (0.7909). Timber with poor combustion performance contributes to the reduction in fire risk in buildings. Our suggestions are of great significance for selecting furniture timber from the perspective of the prevention and control of building fires. [ABSTRACT FROM AUTHOR]

The addition of calcium carbonate to cigarette paper can enhance its combustion performance and apparent properties. However, it does come at the cost of reduced paper strength. In this study, a flexible calcium carbonate (FCC) was developed through the in-situ formation of calcium carbonate on nanocellulose surfaces. The incorporation of FCC into cigarette paper offered the potential to improve filler retention and combustion performance while maintaining high paper strength. The results of the study demonstrated that when compared to the addition of 30% precipitated calcium carbonate (PCC), the filler retention rate in cigarette paper increased by 31.5% when 30% FCC was used. Scanning electron microscopy images showed that only a minimal number of inorganic particles were observed between the fibers in the FCC-containing paper, indicating appropriate air permeability and fiber-fiber bond strength. Furthermore, when compared to PCC-containing paper, the FCC-containing paper exhibited an 8.8% increase in tensile strength and a 7.5% increase in folding resistance. Additionally, thermogravimetric analysis of the cigarette paper revealed that the incorporation of flexible calcium carbonate effectively lowered the thermal decomposition temperature, leading to a 10.3% increase in the combustion rate of FCC-containing paper. The inclusion of FCC into paper fibers has the potential to enhance air permeability and regulate cigarette burning performance. Consequently, the FCC developed in this study holds promise as a substitute for traditional calcium carbonate fillers in cigarette paper applications. [ABSTRACT FROM AUTHOR]

In order to explore the thermal decomposition and combustion performances of zirconium powder (Zr) with high-energy oxidant composite, the thermal decomposition behavior, combustion heat and ignition combustion process of four kinds of energetic materials (EMs) of AP, CL-20, HMX, DAP-4 and Zr/EMs samples were compared and analyzed by using differential scanning calorimetry, automatic calorimetry and self-built combustion experimental system. Some combustion products were collected and characterized. The combustion mechanism of Zr/DAP-4 was analyzed. Results show that the thermal stability and combustion heat release of DAP-4 are better than that of the other three EMs samples. The addition of Zr leads to a higher combustion heat and a lower fa value of the sample, the thermal decomposition temperature remains at 373.8°C, and the combustion performance is better than that of pure DAP-4. Compared with the thermal decomposition of Zr/CL-20 and Zr/ HMX, Zr/DAP-4 has a higher initial decomposition temperature and peak temperature, a lower apparent activation energy fa (138. 7 kj/mol), and a higher combustion heat (17 134J/g). The entire combustion time of Zr/DAP-4 composite is only 170ms, indicating a rapid and intense combustion reaction and its flame intensity is also superior to the other three samples. The combustion products of Zr/DAP-4 include solid products such as ZrO2 and gas products such as H2O and HCI. Zr/DAP-4 composite energetic material has higher energy characteristics and better combustion performances, which make it has great potential for application in the formulation design of propellants. [ABSTRACT FROM AUTHOR]

A new carrier explosive TNBA was batch synthesized by a chemical method. The prepared samples were characterized using SEM, EDS, XRD, IR, XPS, nuclear magnetic resonance, and elemental analysis techniques. The enthalpy of formation of TNBA was measured using a specialized calorimeter that is specially used in testing of explosives and powders. The thermal decomposition performance of TNBA was tested by DSC technology. Meanwhile, the combustion performance of TNBA was also tested. The results of characterizations showed that the prepared sample was indeed TNBA. The enthalpy of formation of TNBA was determined as ΔHf,TNBA=+48.5 kJ/mol. At a heating rate of 20 °C/min, the thermal decomposition peak of TNBA is at TP=285.3 °C, and the activation energy is EK=91 kJ/mol, which is higher than the Tp and EK values of TNT. This indicates that TNBA is a relatively easy to decompose explosive, but the decomposition rate is not fast. The critical temperature for thermal explosion of TNBA reached Tb=247 °C, which is higher than the Tb value of TNT, slightly lower than the Tb value of DNAN, and significantly higher than the Tb value of DNTF, TNAZ, and MTNP. The combustion performance test results showed that the TNBA sample has the highest combustion pressure and the highest pressurization rate; and the TNBA sample has the highest combustion temperature; however, due to the high oxygen balance, the combustion heat of TNBA samples in excess pure oxygen is not the highest. [ABSTRACT FROM AUTHOR]

DAP-4(C6H18N3Cl3O12) is a novel molecular perovskite energetic materials compound that is characterized by high energy, high thermal stability and high oxidation stability. The properties of DAP-4 were enhanced by preparing mixtures of 5%, 10%, 15%, 20%, and 30%SnO2/Al/DAP-4 using the solvent evaporation method. The morphology and structure of the samples were characterized using scanning electron microscopy and energy dispersive spectroscopy. The thermal decomposition characteristics of the samples were analyzed using differential scanning calorimetry and thermal reconnection techniques. The combustion performance test device was used to comparatively analyze the burning pressure, flame temperature, and heat of combustion of the samples. The optimal preparation ratio was determined, and the thermal decomposition mechanism of the SnO2/Al/DAP-4 mixture was deduced. The findings suggest that: The SnO2 and Al powders can be uniformly mixed with DAP-4, leading to the creation of a SnO2/Al/DAP-4 composite that displays outstanding dispersion properties. At the optimal preparation ratio of 20%SnO2/Al, the activation energy required for the thermal decomposition of SnO2/Al/DAP-4 is the lowest, at 106 kJ mol−1. This leads to a significant decrease in the peak temperature of the exothermic decomposition of DAP-4. During the combustion process, the addition of 20%SnO2/Al significantly increased the combustion intensity of DAP-4. This resulted in an increase in the combustion pressure up to 1.1 MPa and a rise in the flame temperature up to 3136 ℃, releasing more combustion heat compared to the feedstock and other proportions of the SnO2/Al/DAP-4 mixtures. [ABSTRACT FROM AUTHOR]

To promote the efficient and clean application of low-carbon alcohol fuels in internal combustion engines, this article compares and studies the effects of three internal EGR strategies, including exhaust valve lift strategy (EVVL), exhaust timing advance strategy (EVT), and intake valve timing advance strategy (IVT), on the combustion, performance, and emissions of gasoline, methanol, and ethanol. Under the same internal EGR rate, the internal EGR temperature generated by the three valve strategies is, from highest to lowest, as follows: EVT, EVVL, and IVT. With an increase in internal EGR in the cylinder, the ignition delay and combustion duration under the EVVL and IVT strategies increase progressively, whereas the ignition delay under the EVT strategy tends to first shorten and then lengthen. Methanol has the shortest combustion duration. Furthermore, methanol and ethanol have lower heat transfer and exhaust losses than gasoline. The thermal efficiency of methanol, ethanol, and gasoline can be raised by 7.7%, 7.5%, and 7.2%, respectively, using the IVT strategy; 3.1%, 3.9%, and 4.6% using the EVVL strategy; and 6.82%, 6.85%, and 7% using the EVT strategy. The combination of methanol and ethanol with internal EGR technology greatly reduces NOx emissions, with an 84.5% reduction under the EVVL strategy. [ABSTRACT FROM AUTHOR]

The combustion and emission characteristics of existing gas turbines using hydrogen-doped fuel were studied. Based on the DLN1. 0 combustion chamber flame cylinder, the numerical simulation method was adopted to study the influence of different hydrogen-doped ratios (a total of 7 operating conditions with volume fraction of H2 ranging from 0 to 30% ) on the combustion process of natural gas mixture under the condition of constant thermal power and the same equivalent ratio. The distribution parameters of the flow field, temperature field and combustion product in a flame cylinder and their corresponding relationships were obtained. The results show that with the increase of hydrogen mixing ratio, the flame temperature rises, the combustion reaction zone expands, and the temperature distribution uniformity at the outlet of the flame tube becomes worse. Hydrogen mixing results in the change of local heat release, which will lead to an increasing trend of NOx emission with the increase of the hydrogen mixing ratio. Both CO and CO2 emissions decrease significantly, while H2 O production increases significantly. At the same time, a proposed dilution combustion method was adopted to solve a series of problems caused by hydrogen mixing, the characteristics changes were studied after hydrogen mixing combustion under different equivalent ratios, and the best equivalent ratio was calculated under each hydrogen mixing ratio. The research results provide theoretical guidance for the subsequent application of hydrogen-doped combustion technology in industrial gas turbines. [ABSTRACT FROM AUTHOR]

This study is focused on the detailed examination of the combustion properties and kinetic analysis of a cellulose acetate fibrous bundle (CAFB), separated from used cigarette filters. It was shown that the faster rate of CAFB heating allows a large amount of heat to be supplied to a combustion system in the initial stages, where the increase in heating rate has a positive response to ignition behavior. The best combustion stability of CAFB is achieved at the lowest heating rate. Through the use of different kinetic methods, it was shown that combustion takes place through two series of consecutive reaction steps and one independent single-step reaction. By optimizing the kinetic parameters within the proposed reaction models, it was found that the steps related to the generation of levoglucosenone (LGO) (by catalytic dehydration of levoglucosan (LG)) and acrolein (by breakdown of glycerol during CAFB burning—which was carried out through glycerol adsorption on a TiO2 surface in a the developed dehydration mechanism) represent rate-controlling steps, which are strongly controlled by applied heating rate. Isothermal predictions have shown that CAFB manifests very good long-term stability at 60 °C (which corresponds to storage in a sea shipping container), while at 200 °C, it shows a sudden loss in thermal stability, which is related to the physical properties of the sample. [ABSTRACT FROM AUTHOR]

Flame retardant barium phytate (PABA) was prepared by phytic acid and barium carbonate. PABA was used to modify flexible polyurethane foam (FPUF) by "one‐step method" to obtain composite FPUF‐PABA. The effects of PABA on the thermal stability and combustion properties of FPUFs were studied by smoke density (Ds), cone calorimeter (CONE), thermogravimetric analysis (TGA), and pyrolysis kinetic analysis. The results indicated that the addition of PABA improved the flame‐retardant properties of the modified FPUFs. The CONE results showed that PABA significantly reduced the PHRR and total heat release (THR) of FPUF, and FPUF‐PABA15 had the lowest PHRR (44.69 kW/m2) and THR (2.49 MJ/m2). TGA showed that FPUF‐PABA15 had maximum residual masses of 27.14%, 26.99%, 28.61%, and 27.25% at four heating rates, respectively. Integral programmed decomposition temperature analysis found that FPUF‐PABA15 also had the highest decomposition temperature, 225.56, 210.54, 148.83, and 162.13°C at four different heating rates. At the same time, the computational activation energy of FPUF‐PABA15 was also the highest, at 133.30, 140.46, and 129.46 kJ/mol, respectively. Ds indicated that FPUF‐PABA15 had the best smoke suppression performance, Ds decreased by 2.47 and light transmittance increased by 2.33%. The current results provide a better formulation for bio‐based flame retardant‐modified FPUF. [ABSTRACT FROM AUTHOR]

In large-bore two-stroke diesel/nature gas dual-fuel marine engines, a certain quantity of diesel is injected into the cylinder to satisfy the full-power output engine rated power of the gas mixture. However, the ignition and flame propagation process based on the injection strategy of diesel direct injection combined with diesel jet flame on the ignition and combustion of natural gas is unclear, which directly affects the power and the thermal efficiency of engine and emissions. Therefore, this work numerically investigates the flame propagation characteristic under the strategy of the main and pilot diesel modes. The influence of the injection timing and proportion of diesel on combustion and emission performance are further analyzed. The results show that the influence of the injection timing of main diesel (MDIT) on the combustion process and emission performance is more obvious than that of the injection timing of pilot diesel (PDIT). The results indicate that the MDIT increased from −2°CA to −8°CA, the power increased by 316 kW, and the thermal efficiency improved by 1.5%. However, the CO2 emissions increased by 10.5 g/kWh, and the NOx emissions increased by 0.7 g/kWh. Additionally, an early PDIT is not conducive to the rapid organization of combustion, resulting in decreased engine power and thermal efficiency. Furthermore, it was found that the power improved by 50 kW and the thermal efficiency improved by 0.6%, with a decrease in the main diesel ratio (MDR) from 100% to 90%. Meanwhile, the CO2 emissions decreased by 4 g/kWh, although there was no obvious change in NOx emissions with the advance of MDR. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development of nano-energetic materials has significantly advanced, leading to enhanced properties and novel applications in areas such as aerospace, defense, energy storage, and automobile. This research aims to engineer multi-dimensional nano-energetic material systems with precise control over energy release rates, spatial distribution, and temporal and pressure history. In this context, sol–gel processing has been explored for the manufacture of nanocomposite aluminum thermites using aerogels. The goal is to produce nano-thermites (Al/Fe2O3) with fast energy release rates that are insensitive to unintended initiation while demonstrating the potential of sol–gel-derived aerogels in terms of versatility, tailored properties, and compatibility. The findings provide insightful conclusions on the influence of factors such as secondary oxidizers (KClO3) and dispersants (n-hexane and acetone) on the reaction kinetics and the sensitivity, playing crucial roles in determining reactivity and combustion performance. In tandem, ignition systems contribute significantly in terms of a high degree of reliability and speed. However, the advantages of using nano-thermites combined with hot bridge-wire systems in terms of ignition and combustion efficiency for potential, practical applications are not well-documented in the literature. Thus, this research also highlights the practicality along with safety and simplicity of use, making nano-Al/Fe2O3-KClO3 in combination with hot bridge-wire ignition a suitable choice for experimental purposes and beyond. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study explores the fire behavior of wood–glass and jute–glass hybrid laminates, with a focus on the influence of jute and wood veneers as new materials for composite production. Five-layer hybrid laminates were manufactured using the vacuum infusion process (VIP). Combustion and carbonization performances were assessed using a cone calorimeter based on the ISO 5660 method. This study evaluates flammability through key parameters including ignition time, heat release rate, and smoke production. The results indicated that the ignition time was significantly longer (ca. 64 s) for the glass–jute laminate (GJGJG), compared to the wood–glass laminate (WGWGW) (ca. 53 s). The heat release rate of laminates containing organic components was higher than the sample composed only of glass mat (G5) but their rates were all lower than the polyester reference resin. WGWGW, compared to the GJGJG sample, was able to produce a good-quality protective shield and, therefore, postpone the occurrence of the heat release peak. In this way, the fire growth rate index (FIGRA) best performance was accomplished by the WGWGW sample (2.7 ± 0.3 kW/m2 × s), which was even better than that of the G5 sample. The total-smoke-released value was highest for polyester, 7361 ± 839 m2/m2, followed by WGWGW, 2873 ± 188 m2/m2, and J5, 2484 ± 216 m2/m2. Among the hybrid laminates, the best performance was obtained by GJGJG, 1860 ± 49 m2/m2, but compared to the G5 laminates, it was only ~36% higher. The specific extinction area (SEA) is a smoke parameter related to the mass of the samples; the best result was obtained by WGWGW with 697 ± 31 m2/kg. Finally, the neat polyester and all laminates achieved UL 94HB classification, with firing rates below 40 mm/min. [ABSTRACT FROM AUTHOR]

Metastable intermolecular composites (MICs) are often used in military and aerospace applications because of their high energy density. However, the traditional preparation methods are either complicated and unsafe, or the prepared composites have incomplete combustion and low energy release rates. In this paper, a series of aluminum/metal oxide/nitrocellulose (AM x N) composite microspheres were prepared by spray drying technique. The field emission scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) results show that the prepared AM x N composite microspheres have regular morphology and uniform particle size, and nitrocellulose (NC) is successfully coated between fuel (Al) and oxidizers (CuO, MoO 3 , and Bi 2 O 3). The thermal reactivity, energy, and combustion properties of AM x N were investigated and compared with physically mixed aluminum/metal oxide (AM x). The explosion heat of AM x N is higher than AM x , while the thermal reaction exothermic peak temperature is lower. Among them, the composite containing copper oxide has the highest explosive heat value (5034 J/g), and the composite containing bismuth oxide has the shortest burning time (2.8 ms). These results prove that NC as a binder shortens the reaction distance between the oxidizer and the fuel in the presence of spray drying. Different oxidizers can modulate the energy release rate of AM x N composites, which is beneficial for applying MICs in energetic materials. [ABSTRACT FROM AUTHOR]

The influence of excess air coefficient, ignition timing, and injection timing were investigated to examine the combustion and emission performance of a hydrogen engine operating at low speed with low loads. Comprehensive experimental research was then undertaken to evaluate the engine performance across a wide range of loads and various combinations of factors. The experimental results show a substantial improvement in brake thermal efficiency (BTE) and a noteworthy reduction in NO X emissions with an increased excess air coefficient. Although the impact of injection timing on BTE is negligible, an appropriate injection timing delay effectively reduces NO X emissions. A lean mixture and a suitable ignition timing delay exhibit high thermal efficiency at a lower engine speed and simultaneously suppress knock. The BTE reaches 33.46% at a mean effective pressure of 10.0 bar. Improving the turbocharging capability under low-speed and high-load conditions is essential for enhancing the performance of hydrogen engines. • EOI has little impact on BTE but is effective in reducing NO X emissions at low load. • Larger excess air ratio can increase BTE and reduce NO X emissions greatly. • Increasing excess air ratio can suppress knock and improve BTE at high load. • Outward-opening injectors are used to decrease hydrogen injection pressure. [ABSTRACT FROM AUTHOR]

The nano-boron powder (n-B) exhibits remarkable efficacy as a combustion catalyst, making it a prime candidate for use in solid propellant metal burners. Nevertheless, throughout the storage phase, the surface of n-B powder is prone to oxidation and substantial agglomeration, resulting in challenges with ignition and incomplete energy dissipation when utilizing boron powder. The synthesis of nano-boron/nitrocellulose/ammonium dinitramide@fluorine rubber (n-B/NC/ADN@F2602) is accomplished via the coaxial electrospinning technique, with n-B uniformly dispersed within the core–shell fiber. The n-B is evenly distributed within the core–shell fiber, and as a result of F2602 encapsulation, the moisture absorption of n-B/NC/ADN@F2602 has decreased from 191.6 to 10.1%. In the course of combustion, the fibrous composite of n-B/NC/ADN@F2602 undergoes an escalation in the rates of energy output and energy release, owing to the constraints imposed by external F2602. The n-B/NC/ADN@F2602 demonstrates a 1.3-fold rise in peak pressure and a 1.15-fold increase in maximum pressure rise rate compared to n-B/NC/ADN. Furthermore, the maximum flame temperature is elevated by 150.5 ℃, and the combustion heat is augmented by approximately 8.7%. The findings of the energy performance assessment reveal that the mean molecular weight (MC) of the combustion byproduct of n-B/NC/ADN@F2602 stands at 27.6 g·mol−1, markedly surpassing that of n-B/NC/ADN. The aforementioned findings exemplify that coaxial electrospinning is an exceedingly efficacious technique for enhancing nanostructures, thereby amplifying the reactivity of energetic particles and offering novel insights into their application in energetic materials. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering for Thermal Energy & Power / Reneng Dongli Gongcheng is the property of Journal of Engineering for Thermal Energy & Power and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Renewable natural gas (RNG) is attractive for energy policy goals in the world. Therefore, a regional system is designed to explore RNG combustion for power generation in localities. This study investigates a direct injection (DI) engine fueled with hydrogen (H2) blended into the simulated renewable natural gas, which consists of 50% methane (CH4) and 50% carbon dioxide (CO2) in volume. In order to obtain higher efficiency, comparisons between DI and port fuel injection (PFI) of H2 addition were made. Then, the volume percentage of H2 was changed from 20% to 100% by keeping the volume ratio of CH4 and CO2 at 1:1. Finally, results of power output, brake mean effective pressure (BMEP), brake thermal efficiency (BTE) and brake specific fuel consumption (BSFC) were discussed. Results showed that in contrast to PFI, H2 DI injection could increase efficiency by 4%. Additionally, H2 DI could retard the MBT ignition timing at 5 °CA. Compared with CH4/CH4 + CO2 combustion, under stoichiometric combustion, BMEP increases with H2 addition but BTE decreases significantly. However, by enlarging the excess air ratio (λ) to 1.24, both BMEP and BTE increase obviously with H2 addition. Moreover, when λ < 1.3, the MBT ignition timing should be advanced from −10 to 15 °CA top dead center (TDC). But the MBT ignition timing is fixed at −25 °CA TDC when λ is larger than 1.3. Furthermore, if efficiency is the priority, 30% H2 addition with λ at 1.24 (−15 °CA TDC) should be selected. If higher BMEP is preferred, 20% H2 addition with λ at 0.99 (−10 °CA TDC) should be selected. [ABSTRACT FROM AUTHOR]

To enhance both the mechanical properties of hydroxyl-terminated polybutadiene (HTPB) binder and the combustion efficiency of aluminized propellants, 2,2,3,3,4,4,5,5-octafluoro-1,6-hexanediol (OFHD) was employed as a chain extender to impart mechanical regulation to the HTPB binder. Mechanical testing showed that the mechanical properties of fluoride-modified HTPB polyurethane (FPU) were significantly improved: the peak tensile strength of the optimized samples reached 1.99 MPa, and the elongation at break attained 486%. The structural characterization of the FPUs was conducted using Fourier transform infrared (FTIR) spectroscopy. Thermogravimetry-mass spectrometer (TG-MS) analysis revealed that the initial thermal decomposition temperature of the FPU shifted from 170 °C to 162 °C, accompanied by the release of fluorine-containing fragments during decomposition. Analysis of the combustion residue indicated that the addition of OFHD can reduce the agglomeration of aluminum (Al) powder in aluminized propellants. Dynamic pressure characteristics results showed an augmented pressurization rate under argon and oxygen atmospheres, increased by 18.67% and 37.29%, respectively. Heat release tests indicated that the aluminized propellants with the addition of OFHD had a higher combustion heat, being increased by 6.57%. The binder system is expected to be applied in aluminized propellants to improve the mechanical properties and combustion efficiency of Al powder. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to investigate the potential of Spirulina platensis (SP), a high protein content microalgae species, to be used as feedstock for a new type of solid biofuel technology, namely bio-coke. The SP bio-coke production was conducted at different formation temperatures of 130, 150 and 170 °C without any binder. The results showed that SP BIC 150, which was produced at the optimum formation temperature of 150 °C, exhibited the highest density and mechanical strength when compared with that of SP BIC 130 and SP BIC 170. This means that it strongly influenced its stable structure during the combustion process. With the strong structure of SP BIC 150, the breakdown of bio-coke can be prevented during flame combustion, thereby contributing to a longer char and total combustion time. The conversion of SP microalgae showed good potential to be used as an alternative renewable energy source in the future.

To overcome the agglomeration and insufficient combustion of nano-boron (n-B) powders, this study successfully prepared two novel types of boron-based nanocomposites using the acoustic resonance technology, namely high-substitute nitrochitosan/nano-boron (NCh-B) with ratios of 1:3, 1:5, 1:7 and 1:9, and nitrochitosan/nano-boron powder/nano-titanium (NCh-B-Ti) with Ti contents of 5 wt%, 10 wt%, 15 wt% and 20 wt%. The structural morphologies, laser ignition and combustion properties of the composites were systematically investigated. The results suggest that the addition of NCh can significantly improve the dispersion of n-B. NCh-B exhibited a higher combustion performance than n-B, as evidenced by their ignition delay and flame areas. When the laser power density was 81 W, NCh-B5-Ti15% exhibited a combustion time and an ignition delay of 240 ms and 5.5 ms respectively, which were higher and lower than those of NCh-B5 (199 ms and 17 ms, respectively). Furthermore, NCh-B5-Ti15% displayed a lower ignition delay than both n-B powders (12 ms) and NCh-B (11 ms), as well as brighter flames and a larger combustion area. Therefore, the addition of n-Ti can promote the combustion of n-B powders, with the combustion products of NCh-B-Ti including H3BO3, B2O3, TiB2, and TiO. This study provides a new method for improving the ignition performance and combustion efficiency of n-B powders.

At present, the selection criteria and configuration methods for fireproof clapboards in cable tunnels are not yet perfect, making it difficult to achieve effective fire protection. Therefore, an equivalent fire condition testing method is proposed to analyze the fire-resistant property of fireproof clapboards of different materials. Firstly, a tunnel fire experiment platform was built to carry out the combustion experiment of the high-voltage cable intermediate joint. The cable combustion equivalent fire source device is developed based on the temperature rise characteristics under different combustion conditions. However, the temperature rise characteristics of the equivalent fire source and the actual cable combustion error are within 10%. Then, four typical fireproof clapboards were tested under equivalent fire sources. The results indicate that the organic molded board has the best performance. In addition, factors such as the thickness, side panel height, and installation method of the fireproof clapboards were tested and analyzed. The results indicate that a minimum thickness of 5 mm for the fireproof clapboard and a height of 200 mm for the side panel of the clapboard are necessary to ensure effective protection. The installation method of hoisting fireproof clapboards can effectively extend the protection time by about 30% compared to the flat method.

Load-following operations of coal power plants are required to cope with the variability in power generation from renewable energy sources. This study aimed to optimize combustion in coal-fired power plants at low loads by analyzing combustion efficiency, NOx emissions, and ash deposition in a boiler. An experiment was conducted by varying the heat input in a bench-scale combustion system. The combustion performance, in terms of the CO concentration in combustion gas and unburned carbon content in ash, degraded during low-load operation. Consequently, the fuel ratio was found to be a key factor for determining the combustion efficiency during low-load operation. The nitrogen content of the fuel was dominant in terms of the NO conversion ratio. The inconsistency in the ash deposition tendency suggested that it was affected more by the composition of minerals than by the amount of ash or total feed rate of ash in coal. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Explosives & Propellants is the property of Chinese Journal of Explosives & Propellants Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Liquid slagging is an important solution for the problem of high-alkali coal slagging. The blending of low-melting-point fuel for combustion can effectively reduce the ash melting point of mixed fuel, improving the efficiency of liquid slagging. In this study, highly active sludge is mixed with Zhundong (ZD) coal. Then, co-combustion characteristics and ash melting behavior are studied by combining thermogravimetric analysis, thermodynamic analysis, ash melting analysis and ash composition analysis. The following results are observed. Ignition temperature is significantly reduced with an increase in sludge blending ratio, and combustion performance deteriorates rapidly when sludge proportion exceeds 20 wt.%. The burn out temperature initially decreases and then increases, reaching its minimum value when the sludge blending ratio is 10 wt.%. The blending of sludge causes the apparent activation of the sample to decrease, enhancing the combustion activity of the mixed fuel. The mixed fuel has lower ash melting point. A eutectic system with low melting point is produced due to the reaction of a large amount of sludge Fe2O3 with SiO2 in coal. The ash melting point is only 1080°C when 10 wt.% sludge is mixed. On the basis of the two considerations for improving combustion performance and reducing the melting point of ash, the recommended optimal blending ratio of sludge is 10 wt.%. [ABSTRACT FROM AUTHOR]

The combustion of natural gas mixed with hydrogen can effectively reduce the emission of carbon. However, the fuel properties will be changed by mixing hydrogen, which will affect the combustion process, so it is necessary to conduct in-depth research on hydrogen-mixing combustion. The combustion characteristics and emission characteristics of gas turbines fueled by mixed hydrogen natural gas were mainly studied. The numerical simulation was adopted to study the effects of different hydrogen-mixed ratios ( 6 working conditions of volume content for 0 ~ 100% H2 ) on the combustion process of GE-10 experimental gas turbine combustion chamber. The results show that with the increase of the hydrogen mixing ratio, the flame temperature is raised and the combustion reaction zone is moved forward. At a low mixing ratio, the temperature distribution at the outlet of the flame cylinder tends to be uniform with the increase in the hydrogen mixing ratio. When the hydrogen blending ratio exceeds 0. 6, the uniformity of temperature distribution at the outlet is greatly decreased. Moreover, increasing hydrogen in the mixed fuel will result in local heat release increases and leads to NOx emission increases. When the hydrogen blending ratio exceeds 0. 8, the increased range of NOx emission becomes larger. At the same time, with the increase in the hydrogen mixing ratio, the emission of CO and CO2 decreases significantly, and the production of H2O increases significantly. This research will provide theoretical guidance for the subsequent application of hydrogenmixed combustion technology in industrial gas turbines. [ABSTRACT FROM AUTHOR]

Liangshan Prefecture is one of the three major forest areas in Sichuan Province and one of the three major disaster areas of forest fire. We measured the physicochemical properties and combustion performances of different organs (leaves and branches) of 15 main economic tree species in Liangshan, and analyzed the bioecology characteristics, silviculture characteristics and value characteristics of different tree species. We investigated the fire resistance of different tree species to screen out fire-resistant species suitable for economic forest development in Liangshan Prefecture, and improve the biological fire prevention ability. The seven physicochemical properties and combustion performances indices of 15 tree species showed significant differences. Except for crude ash and lignin, the weights of moisture content, caloric value, ignition point, crude fat, and crude fibre of leaves were higher than those of branches. Crude fibre index of leaves (9.6%) and the crude ash index of branches (9.9%) were the highest weight indices of the two organs, respectively. Based on the fire resistance, we divided all the species into three classes, i.e., class I (excellent fire-resistance trees) Juglans regia and Morus alba; class II (better fire-resistant trees) Sapium sebiferum, Mangifera indica, Phyllanthus emblica, Eriobotrya japonica, Ligustrum lucidum, Castanea mollissima, and Punica granatum; class III (poor fire-resistant trees) Pinus armandii, Illicium simonsii, Morella rubra, Sapindus mukorossi, Olea europaea and Camellia oleifera. J. regia and M. alba had fireproof solid performance and could be used as the preferred species for fireproof economic forest in Liangshan region. It was suggested that to use class I to II fire-resistant tree species built the main fireproof isolated forest belt, and pay attention to fire prevention after planting class III tree species in a large area. [ABSTRACT FROM AUTHOR]

Water hyacinth(WH) is a promising resource produced as a by-product of treating pollution in watersheds, but little study has been done on its high-value applications. In this work, the combustion characteristics of WH, anthracite (AN), and their blends under different ratios, and heating rates were investigated by the thermogravimetric (TG) analyzer. The Kissen-Akahira-Sunose (KAS) and Flynn-WallOzawa (FWO) methods are used to calculate the dynamics, and the interaction between the mixed materials is discussed. The results show that the combustion characteristics of WH are better than those of AN because of its higher volatile components. With the increase of WH, the comprehensive combustion index increased from 0.15(pure AN) to 2.22(WH: AN=5:5). With the increase in heating rate, there is no significant difference in residual. The difference in thermogravimetric curves of mixed fuel in the volatile combustion stage and fixed carbon combustion stage shows that there is an interaction between WH and AN in the process of co-combustion, indicating that the mixed fuel is suitable for co-combustion. This study provides a theoretical basis for improving the efficiency of clean energy and reducing the consumption of fossil energy. [Display omitted] • The comprehensive combustion index increased significantly from 0.15 to 2.22. • 5:5 is a better solution for co-firing WH with AN. • There are interactions between WH and AN co-firing. [ABSTRACT FROM AUTHOR]

This paper describes a study of combustion performance of a Bi2O3/Al nanothermite mixture with the addition of 1-methyl-3-nitro-1,2,4-triazole (1Me-3N) depending on the content of the latter and the component ratio of a base Bi2O3/Al nanothermite pair. Adding 1Me-3N to the mixture increases the explosive force, but the latter begins to decrease as soon as the additive content reaches over a certain limit. Depending on the prescription configuration, it is possible to increase the explosive force by 22–29% relative to Bi2O3/Al nanothermite. Changing the prescription configuration makes it possible to vary the burning rate of Bi2O3/Al/1Me-3N within a range of 400–690 m/s in charges 2 mm in diameter and within a range of 120–430 m/s in a 0.1-mm thick layer. [ABSTRACT FROM AUTHOR]

Particle boards are manufactured through a hot pressing process using wood materials (natural polymer materials) and adhesive, which find common usage in indoor decorative finishing materials. Flame-retardant particleboard, crucial for fire safety in such applications, undergoes performance analysis that includes assessing temperature distribution across its facing surface and temperature increase on the backside surface during facade combustion, yielding critical insights into fire scenario development. In this study, a compact flame spread apparatus is utilized to examine the flame retardancy and combustion behavior of particle boards, with a specific emphasis on the application of cost-effective flame retardants, encompassing aluminum hypophosphite (ALHP), an intumescent flame retardant (IFR) comprising ammonium polyphosphate (APP), melamine (MEL), and Dipentaerythritol (DPE), alongside magnesium hydroxide (MDH), and their associated combustion characteristics. The D300°C values, representing the vertical distance from the ignition point (IP) to P300°C (the temperature point at 300 °C farthest from IP), are measured using a compact temperature distribution measurement platform. For MDH/PB, APP + MEL + DPE/PB, and ALHP/PB samples, the respective D300°C values of 145.79 mm, 117.81 mm, and 118.57 mm indicate reductions of 11.11%, 28.17%, and 27.71%, compared to the untreated sample's value of 164.02 mm. The particle boards treated with ALHP, IFR, and MDH demonstrated distinct flame-retardant mechanisms. MDH/PB relied on the thermal decomposition of MDH to produce MgO and H2O for flame retardancy, while APP + MEL + DPE/PB achieved flame retardancy through a cross-linked structure with char expansion, polyphosphate, and pyrophosphate during combustion. On the other hand, ALHP/PB attained flame retardancy by reacting with wood materials and adhesives, forming a stable condensed P-N-C structure. This study serves as a performance reference for the production of cost-effective flame-resistant particleboards and offers a practical method for assessing its fire-resistant properties when used as a decorative finishing material on facades in real fire situations. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)