Carbon Particles Research Articles

Study on the Sound Absorption Characteristics and Noise Reduction Mechanism of Coconut-Shell-Activated Carbon Particles and Coconut Fiber Composite Biomass Sound-Absorption Materials

Abstract Sound absorbing materials are widely used in the field of automotive industry. Biomass materials are abundant in nature, and some biomass has natural sound absorption and noise reduction properties. Biomass sound absorption material is green and pollution-free, and has obvious noise reduction effect on middle and high frequency noise, large specific surface area, light weight, and strong sound absorption effect. In order to analyze the sound absorption and physical properties of biomass sound absorbing materials, the noise reduction performance of the different structure of biomass sound absorbing materials were analyzed. In this paper, the biomass sound absorbing materials coconut fiber and coconut shell activated carbon particles were used to make samples. Coconut shell activated carbon sound absorption material (CSAC) was made. The cylindrical holes was made and filled with coconut fiber materials to form composite sound absorbing materials (CSAC-F). The acoustic performance of impedance tube was tested based on the acoustic absorption coefficient, and the physical performance was studied by means of Scanning Electron Microscope (SEM), Brunauer, Emmett and Teller (BET), X-ray diffraction (XRD), Fourier Transform Infrared Spectrometer (FTIR), Thermogravimetric (TGA) and other detection methods. In contrast, the sound absorption effect of CSAC-F was better in the middle and low frequency range. The microstructure of the material was analyzed and the mechanism of noise reduction was studied. This research will provide a new way for the research and development of sound absorbing materials in the automotive industry, and biomass sound absorbing materials have potential applications in the noise absorption and vibration control of automotive interior.

Preparation of Activated Carbon- and Graphite-Coated Banana Fibers as Flame-Retardant Materials

In polymer studies, biocomposite now draws attention as an exciting material obtained from combining natural fiber and matrix, which is an environmentally friendly material with biodegradable properties. One of the natural fibers often used in polymer filler is banana stem fiber. This study aims to prepare carbon-coated waste-dried banana fiber. The waste of banana stems was used as raw material for preparing cellulose-rich banana stem fiber. The banana fiber was soaked in an alkaline solvent, 1% NaOH, to remove the lignin content. The dried banana fiber was then coated with activated carbon and graphite by immersion in the carbon dispersion in ethanol with PVA glue binder added. Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) spectra show different profiles on raw and carbon-coated banana fibers, indicating successful carbon coating. The burning test and thermal analysis results show that carbon-coated banana fibers have better thermal properties than raw banana fiber. This suggests that carbon covered on the fiber surface could enhance its thermal property due to intramolecular bonds between fibers and carbon particles. Graphite-coated banana fibers have the longest burning time and are concluded to have the best fire-retardant properties among all samples. The findings confirmed the potential use of carbon-coated banana fiber as filler material for reinforcing conventional composites.

Selective Self‐Assembly of Atomically Dispersed Iron and Cobalt Dual Atom Catalyst on Anisotropic Mesoporous Carbon Particles for High Performance Seawater Batteries

AbstractNa‐seawater batteries (SWBs) are environmentally friendly energy storage system that utilizes abundant seawater as an electrolyte alternative to conventional distilled water‐based and organic electrolytes. To achieve high energy efficiency in Na‐SWBs, it is necessary to enhance the activity of bifunctional oxygen electrocatalysts. In this study, an atomically dispersed iron and cobalt dual‐atom nitrogen‐doped lens‐shaped mesoporous carbon (FeCo‐LMC) particles is synthesized as a SWB cathode material using the spinodal decomposition of the polymer blend and selective precursor positioning. The well‐aligned mesoporous structure and synergetic effect of the dual‐atom site realize FeCo‐LMC as a comparable bifunctional oxygen catalyst with the lowest overpotential difference (EOER−EORR) among the other catalysts with natural seawater electrolyte. When applied to the SWB system, the FeCo‐LMC shows a highly improved charge/discharge performance compared to Pt/C and a stable cycling performance for 200 h. Density functional theory calculations reveal the enhanced oxygen catalytic activity of FeCo‐LMC owing to electron delocalization and d‐band center adjustment of FeN4–CoN4 structure.

Construction of an Anode Material for Sodium-Ion Batteries with an Ultrastable Structure.

The reserves of sodium resources are much larger than those of lithium resources, and they are widely distributed and easy to produce and can be widely used in photovoltaic energy storage and other industries on the premise of this advantage. However, how to produce hard carbon anodes at a low cost for the preparation of energy storage materials requires continuous exploration and experimentation to find the optimal solution. Here, we used waste sour date shell biomass as a precursor for a hard carbon anode obtained by simple acid treatment and two pyrolyses. It is shown that acid washing after prepyrolysis has a significant effect on the electrochemical performance of the sour date shell-derived hard carbon (ZJ), constructing a stable structure that makes it easier for sodium ions to be embedded and dislodged, and the carbon particles are homogeneous and free of bonding and electrode cracking. The ZJ-1500-HCl pyrolyzed at 1500 °C has a high reversible capacity of 329.1 mAh g-1, 94.1% initial Coulombic efficiency (ICE), 90.54% capacity retention efficiency cycling 300 cycles at a current density of 300 mA g-1, and a resistivity below 10 Ω. It has good cycle stability and a good multiplier performance. It is expected to be used in practical production and photovoltaic energy storage in the future.

Electrophoretic deposition of carbon-ionomer layers on proton conducting membranes.

Synthetic and natural carbons are widely used as carrier for electrodes in electrochemical applications. They need to have a controlled morphology in order to facilitate mass and charge transport, so the process of film formation is of uttermost importance. Here we show, how carbons (after proper preconditioning) can be codeposited with an ionomer by electrophoretic deposition, a method that does allow full control of deposition conditions during the process. In view of potential applications, we focus on the direct deposition on proton-conducting membranes. Ionomers and membranes applied are based on established per-fluorinated polyethylene with SO3H-terminated side chains (PFSA). Conditions for reproducible deposition are reported in terms of optimal charge on the carbon particles, field strength in the deposition cell and necessary deposition times for a given film thickness. Additionally, a horizontal cell arrangement is suggested to avoid gravitational effects.

A Natural Carbon Encapsulated in Gellan-Based Hydrogel Particles Designed for Environmental Challenges

This article reports the obtention of a new gellan-based hydrogel linked with Fe3+ and loaded with a natural micro/nanostructured carbon designed as a contaminant’s removal from wastewater. Hydrogels are known for their water-retaining properties, high binding capacity, and eco-friendly features. The new material is expected to behave as one cost-effective and efficient sorbent, including natural carbon structures with various functional groups. The encapsulation efficiency ranges between 89% and 95%. The obtained hydrogel particles were characterized using FT-IR spectroscopy and scanning electron microscopy techniques. The hydrogel particles’ water stability was evaluated by measuring the transmittance for 10 days, and the capacity to retain water was assessed by determining the swelling degree (Q%). The results showed that hydrogel particles are stable (the transmittance value is higher than 97.8% after 10 days), and their properties are influenced by the cross-linking degree, the amount of the carbon particles encapsulated, and the concentration of gellan. For example, the Q% values and encapsulation efficiency increased when the cross-linking degree, the carbon microstructure quantity, and the gellan concentration decreased. The new hybrid material can retain Pb(II) ions and diclofenac molecules, and could be used in different adsorption–desorption cycles.

Experimental Investigations of Friction Properties of Carbon Particles Derived from Sargassum Algae

In Caribbean islands, the washing ashore of tons of pelagic Sargassum spp., consisting of two species Sargassum fluitans and Sargassum natans, has been regularly occurring since 2011. As green lubrication is a growing trend in the tribology industry, biochar is a promising alternative. Sargassum biochars, produced from Sargassum pelagic algae, are therefore being studied as solid lubricants. This study aims to explore their potential applications. Biochars from brown algae were pyrolyzed at 400 °C and then annealed at different temperatures (from 600 °C to 1500 °C). The Raman spectra collected on the different biochars showed that there was a structural organization of the biochars as the temperature increased. The tribologic properties of the biochars were studied and compared to a solid lubricant reference (exfoliated graphite). Raman spectroscopy analysis revealed a progressive structural reorganization with increasing temperature, leading to a 58% reduction in the coefficient of friction. The morphology and the structure of the tribofilm are investigated by profilometry, scanning electron microscopy, and Raman microspectrometry. Overall, these results can be considered as a first step for utilizing the biochar derived from brown algae Sargassum sp. as an additive in the lubricant industry, for the purpose of emission reduction.

Exploring fine-aerosol episodes in urban Seoul during the cold season of the 2021 SIJAQ campaign: Measurement evidences of heterogeneous reactions on black carbon particles

Exploring fine-aerosol episodes in urban Seoul during the cold season of the 2021 SIJAQ campaign: Measurement evidences of heterogeneous reactions on black carbon particles

Carbon primer layer morphological effect on the lithium manganese iron phosphate positive electrode performances for lithium-ion batteries

The use of lithium manganese iron phosphate (LMFP) electrodes is important for enhancing the energy density of phosphate-based positive electrodes. However, their practical application is hindered by the deteriorating collector–electrode interface caused by submicron-sized particles with carbon-coated surfaces. The morphology of these carbon particles affects the efficiency of the primer layer, despite its role in strengthening the electrical contact between LMFP and the aluminum (Al) current collector. Incorporating carbon nanotube (CNT)-type carbon into the primer layer weakens the electrical connection between the electrode mass and current collector, indicating that CNT-coated Al does not effectively reduce contact resistance. In contrast, the planar shape of graphene-type carbon provides a more effective connection between LMFP and the Al plate, resulting in minimal contact resistance. This improvement in contact resistance enhances cycleability by significantly reducing polarization during cycling, which prevents electrolyte decomposition on the LMFP surface. Given the significant impact of carbon morphology on interfacial contact, it is essential to rationally control the morphology of the carbon primer layer to optimize the properties of the positive electrode.

Preparation of high flux low‐cost ceramics membrane supports with oil‐based drilling cutting pyrolysis residues (ODPRs) as raw material

AbstractLow‐cost ceramic membrane support is important for the filtration performance of a asymmetry filtration membrane. In this study, the oil‐based drilling cutting pyrolysis residues (ODPRs) were used as raw materials incorporating with fly ash, and carbon particles were used as pore‐forming agents to prepare high‐flux low‐cost ceramic membrane supports. Besides the strength of the supports was decreased with increased carbon particles addition and size, the porosity, pore size and consequently the Darcey permeability k1 and pure water permeability of the support were increased with the increased carbon particle addition and size. The chemical stability of the support was deteriorated with the increased carbon particles addition. A leaching test on the support with 10% 12 µm carbon particle addition indicates that the support obtained by using the ODPRs incorporating with fly ash as raw materials is safe for aqueous filtration. This study showcased the utilization of ODPRs as a primary resource to manufacture a high‐permeability support for water filtration. This approach aligns with the principles of sustainable development, following a waste‐to‐product‐to‐environment pathway.

Effect of Rheological on the Physical and Electrical Properties of Extruded Micro Carbon -LLDPE Composites

This study focuses on formulating and optimizing a conductive polymer composite (CPC) material tailored for electromechanical applications. Linear Low-Density Polyethylene (LLDPE) polymer and micro carbon particles derived from rice husk were compounded using a hot compaction process and melt blended through a single-screw extrusion machine. A mix of 50% loading of microcarbon particles was used in this research. It was determined that the experiment was successfully conducted, resulting in a stabilized density of approximately 1 g/cm³. The research demonstrates how the prototype Extruder Head effectively stabilizes the density of composites. Electrical conductivity demonstrated a notable increase in conductivity toward higher density. These findings underscore the successful development of a CPC material with improved electrical conductivity, making it a highly suitable tool for high carbon-loading composite material.

Autoignition of premixed hydrogen/air mixtures with uniformly dispersed carbon particles

The autoignition of a stoichiometric hydrogen/air mixture laden with uniformly distributed coal char particles is simulated with the Eulerian-Lagrangian approach under isochoric conditions. A zero-dimensional model is adopted to assess the effects of gas temperature, pressure, particle diameter, and concentration on ignition dynamics. Increasing the initial temperature reduces the ignition time and maximum heat release rate of the homogeneous reactions, while the parameters for particle reactions stabilize after reaching a critical temperature. Initial pressure exhibits a non-monotonic influence on gas phase ignition, with higher pressures promoting particle autoignition. An increase in particle diameter decreases the ignition time for the homogeneous reaction, approaching that of particle-free conditions. Meanwhile, particle ignition time first decreases and then linearly increases. Increasing particle concentration reduces the interphase disparities of ignition times, while the two-phase ignition times rapidly rise after exceeding the critical concentration. Moreover, pre-ignition temperature equilibrium (PTE) significantly impacts the ignition parameters and processes. PTE results in a minimal ignition time disparity between the gas and particles, with coal char particles markedly influencing hydrogen ignition. Failure to reach PTE leads to significant two-phase ignition time differences, with negligible impact from the solid phase on gas phase ignition. The particle effect ratio, δ, is introduced to evaluate these effects. Notably, the evolution variations in ignition time and heat release rate are determined by the existence of the PTE under corresponding initial conditions. The findings of this study are crucial for developing strategies to mitigate explosion hazards and enhance the performance of detonation propulsion systems using hybrid fuels.

Overcoming the Limitation of Ionomers on Mass Transport and Pt Activity to Achieve High-Performing Membrane Electrode Assembly.

The membrane electrode assembly (MEA) is one of the critical components in proton exchange membrane fuel cells (PEMFCs). However, the conventional MEA cathode with a covered-type catalyst/ionomer interfacial structure severely limits oxygen transport efficiency and Pt activity, hardly achieving the theoretical performance upper bound of PEMFCs. Here, we design a noncovered catalyst/ionomer interfacial structure with low proton transport resistance and high oxygen transport efficiency in the cathode catalyst layer (CL). This noncovered interfacial structure employs the ionomer cross-linked carbon particles as long-range and fast proton transport channels and prevents the ionomer from directly covering the Pt/C catalyst surface in the CL, freeing the oxygen diffusion process from passing through the dense ionomer covering layer to the Pt surface. Moreover, the structure improves oxygen transport within the pores of the CL and achieves more than 20% lower pressure-independent oxygen transport resistance compared to the covered-type structure. Fuel-cell diagnostics demonstrate that the noncovered catalyst/ionomer interfacial structure provides exceptional fuel-cell performance across the kinetic and mass transport-limited regions, with 77% and 67% higher peak power density than the covered-type interfacial structure under 0 kPagauge of oxygen and air conditions, respectively. This alternative interfacial structure provides a new direction for optimizing the electrode structure and improving mass-transport paths of MEA.

Alterations in the placental proteome in association with the presence of black carbon particles: A discovery study

BackgroundExposure to ambient air pollution is known to cause direct and indirect molecular expression changes in the placenta, on the DNA, mRNA, and protein levels. Ambient black carbon (BC) particles can be found in the human placenta already very early in gestation. However, the effect of in utero BC exposure on the entire placental proteome has never been studied to date. ObjectivesWe explored whether placental proteome differs between mothers exposed to either high or low BC levels throughout the entire pregnancy. MethodsWe used placental tissue samples from the ENVIRONAGE birth cohort, of 20 non-smoking, maternal- and neonate characteristic-matched women exposed to high (n = 10) or low (n = 10) levels of ambient BC throughout pregnancy. We modeled prenatal BC exposure levels based on the mother's home address and measured BC levels in the fetal side of the placenta. The placental proteome was analyzed by nano-liquid chromatography Q-TOF mass spectrometry. PEAKS software was used for protein identification and label-free quantification. Protein-protein interaction and functional pathway enrichment analyses were performed with the Search Tool for the Retrieval of Interacting Genes/Proteins (STRING) software. ResultsThe accumulation of BC particles in placenta was 2.19 times higher in the high versus low exposure group (20943.4 vs 9542.7 particles/mm³; p = 0.007). Thirteen proteins showed a ≥2-fold expression difference between the two exposure groups, all overexpressed in the placentas of women prenatally exposed to high BC levels. Three protein-protein interactions were enriched within this group, namely between TIMP3 and COL4A2, SERPINE2 and COL4A2, and SERPINE2 and GP1BB. Functional pathway enrichment analysis put forward pathways involved in extracellular matrix-receptor interaction, fibrin clot formation, and sodium ion transport regulation. DiscussionPrenatal BC exposure affects the placental proteome. Future research should focus on the potential consequences of these alterations on placental functioning, and health and disease during early childhood development.

Ignition of anthracite microparticles by continuous laser radiation with wavelengths of 450 and 808 nm

The energy and spectral-kinetic characteristics of ignition of anthracite microparticle powders with a bulk density of 0.5 g/cm3 were measured when exposed to continuous laser radiation at wavelengths λ = 450 and 808 nm with an exposure time of 1 second. Ignition delay times were measured depending on the radiation power density and critical values of the ignition energy density of anthracite samples were determined. The energy cost of igniting anthracite for radiation with λ = 450 nm is less than for radiation with λ = 808 nm. In the emission spectra of anthracite resulting from the absorption of laser radiation, there is a glow associated with the release and ignition of volatile substances (flame CO, glow of excited molecules CO, C2 and H2O) and thermal glow associated mainly with the heated surface of the samples, as well as the flight of incandescent carbon particles.

Experimental Study of Erosion Prevention Model by Bio-Cement Sand

Microbially induced carbonate precipitation (MICP) technology is employed to reinforce the surface soil of a dam, aiming to prevent erosion caused by water flow and damage to the dam slope. The relationship between penetration depth, calcium carbonate content, and bonding depth was investigated at eight measuring points on the sand slope surface of a mold under different reinforcement durations. It was observed that as grouting reinforcement times increased, there was a gradual increase in calcium carbonate content but a rapid rise in penetration resistance. Moreover, the bonding depth of sand on the bio-reinforced sand slope increased with higher levels of calcium carbonate content. Microbial grouting reinforcement enhanced soil particle bonding force, requiring water flow to overcome this force for activation of sand particles. Consequently, microbial grouting reinforcement significantly improved shear strength and critical starting flow velocity on sand slope surfaces. The experimental results demonstrated that after MICP surface treatment through spraying, a dense and water-stable hard shell layer composed of bonded calcium carbonate and soil particles formed continuously on sample surfaces, effectively enhancing the strength and erosion resistance of sandy soils. These findings provide reliable evidence for silt slope reinforcement and dam erosion prevention.

Эффект интенсивного окисления сероводорода дымовых газов содорегенерационного котла при производстве целлюлозы

Despite the transition to the Swedish technology for regenerating black liquor from pulp production plants, even in those regions of Russia where the standard daily average levels of hydrogen sulfide and methyl mercaptan in the air of populated areas have been achieved, a number of problems remain with emissions of reduced sulfur. In many cities, onetime concentrations of reduced sulfur, especially at night, may exceed the permissible ones. In addition to flue gas emissions from soda recovery boilers, there are other, less intensive sources of harmful emissions in the cooking, evaporation and wood-chemical workshops, in the causticization and lime regeneration workshops, there are emissions from unorganized sources and from the open surface of wastewater treatment facilities. The population living near such plants feels the unpleasant odor of methyl mercaptan. This study has aimed to develop a new technology for reducing gas emissions of reduced sulfur into the environment, applicaple for different sources. The results of testing an industrial installation for purification of gas emissions from a soda recovery boiler in a scrubber with nozzle irrigation have been presented. Based on the measurements of the technological parameters of the operation mode of the gas purification plant and the determination of the composition of the irrigation solution, the analysis of the results obtained has been performed. During the tests, a high degree of hydrogen sulfide capture at a low pH value has been achieved. It has been established that hydrogen sulfide has been captured as a result of its oxidation before entering the irrigation solution in fine droplets of condensate formed on micron-sized particles of sulfate and sodium carbonate. The results of this study have been compared with the results of the studies conducted by Stanford University and the P.P. Shirshov Institute of Oceanology of the Russian Academy of Sciences. The possibility of hydrogen peroxide formation under our test conditions in the surface layer of fine droplets formed during the condensation of water vapour on dust particles has been analyzed. The suposed cause of the obtained effect has been determined to be the thermomechanical deformation of the surface layer of the droplets.

Analysis of superheated steam influence on the content of solid carbon particles during diffusion combustion of liquid hydrocarbon fuel

Analysis of superheated steam influence on the content of solid carbon particles during diffusion combustion of liquid hydrocarbon fuel

Sustainable Energy Solutions in Sub-Saharan Africa: Integrating Indigenous Knowledge and Climate Resilience for Lower Carbon Emissions

Promoting sustainable energy solutions in sub-Saharan countries is crucial for addressing energy poverty, reducing carbon emissions, and fostering long-term environmental and economic sustainability. This study explored using indigenous knowledge and emerging technologies to reduce carbon footprints and GHG emissions in Africa's climate hotspots in sub-Saharan countries. The study revealed that operating institutions utilize various applications to ensure that energy management resources can mitigate the effects of carbon emissions. The study revealed that the most efficient use of natural resources for energy production requires collaboration among governments, private sectors, NGOs, and local communities. By adopting a holistic and inclusive approach, one can work toward a more sustainable and low-carbon energy future. This paper focuses on carbon footprint analysis and proposes solutions to address environmental issues in implementing sustainable energy solutions in sub-Saharan countries. A multifaceted approach involving effective strategies is needed to lower the carbon footprint. The contribution of this study is to improve energy consumption in communities in Africa by integrating climate resilience considerations into sustainable energy projects to ensure long-term viability. This will involve planning for changing climate conditions, such as extreme weather events, and designing infrastructure that can withstand and adapt to these challenges. It has been concluded that carbon footprint analysis is useful for determining the impacts of carbon particles in the world’s atmosphere. The role of energy management operations seeks to improve the assessment and analysis of carbon footprints by allowing atmospheric measurements of carbon.

Evaluation of Anti-Inflammatory and Immunosuppressant Potential of Isotelekin in Lipopolysaccharide (LPS) Stimulated Macrophage (RAW 264.7) and Sheep Red Blood Cells (SRBC) Sensitized Murine Models.

The present study explored the natural compound Isotelekin isolated from Inula racemose against anti-inflammatory and immunomodulatory potential in LPS-induced RAW264.7 cell lines and immune-elevated SRBC-sensitized animal models. Isotelekin in in vitro studies, inhibited the production of Th-1 cytokines Interleukin-6 (IL-6), Tumour necrosis factor (TNF-α), and Interferon-gamma (INF-γ),and increased Th-2 cytokines Interleukin-10 (IL-10). Whereas it inhibited the nitrites and reactive oxygen species (ROS) production by mitigating the effect of LPS significantly. In vivo immunomodulatory activity in Delayed-type hypersensitivity (DTH) and Hemagglutinating antibody (HA), Isotelekin suppressed the cellular as well as humoral immunity in immune-affected and SRBC-sensitized mice. Isotelekin decreased the phagocytic responses against carbon particles and plaque-forming mainly IgG (Immunoglobulin G) production. Additionally, Isotelekin showed immunosuppressive potential through the evaluation of splenocytes, allograft acceptance, and haematological parameters. Molecular studies, including western blot analysis and immunocytochemistry, revealed that Isotelekin reduced the expression of iNOS (Inducible nitric oxide synthase), COX-2 (Cyclo-Oxygenase 2), and p-IkBα (Phospho I-kappa-B-alpha), and significantly inhibited the nuclear translocation of NF-κB/p65. Based on these results, Isotelekin at 10 µm in in vitro and at 30mgkg-1 in in vivo demonstrated strong anti-inflammatory and immunosuppressive therapeutic potential.