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Downsizing Pt-based catalysts to generate a higher surface-to-volume ratio and maximize atom utilization efficiency has been recognized as an effective strategy to achieve high mass activity. However, the synthesis of homogeneous, ultra-small bimetallic nanoclusters remains a significant challenge due to the difficulties in controlling stoichiometry and surface state control, large miscible gaps between different metals and surface state changes induced by the reaction gas environment. In this paper, bimetallic Pt-based nanoclusters such as PtPd, PtRu, PtCu deposited on carbon black (Vulcan XC72R) were fabricated by the reduction of H 2 plasma.The structure and morphology of those prepared catalysts were revealed by HAADF-STEM, HR-TEM, EDS and XPS. The results indicated the prepared Pt-based nanoclusters displayed high dispersibility and small size owning to the non-equilibrium characteristics of non-thermal plasma (NTPs). The average sizes of PtPd, PtRu and PtCu were 2.06 ± 0.68 nm, 3.66 ± 1.34 nm and 1.98 ± 0.7 nm, respectively. Meanwhile, the synthesized PtPd nanoclusters with the ratio of 3:4 exhibited high catalytic activity in the hydrogen evolution reaction (HER). The Pt 3 Pd 4 /VR-P displayed a low overpotential (19 mV) at 10 mA/cm2 and achieved a high mass activity of 5.4 A/mg for HER in 0.5 M H 2 SO 4 solution, which was 13.8 times higher than those of the commercial Pt/C catalysts. Moreover, the Pt 3 Pd 4 /VR-P demonstrated excellent stability with a negatively shifting about 40 mV after 10,000 cycles at a current density of 10 mA/cm2, which was close to that of JM-Pt/C (32 mV). The results prove NTPs technology is effective for the preparation of bimetallic Pt-based nanoclusters. Non-thermal plasma is an innovative method to prepare Pt-based nanoclusters with high dispersibility and small size. The synthesized Pt 3 Pd 4 nanoclusters with an average size of 2.06 ± 0.68 nm displayed a low overpotential (19 mV) at 10 mA/cm2 and achieved a high mass activity of 5.4 A/mg for HER in 0.5 M H 2 SO 4 solution, which was 13.8 times higher than that of the commercial Pt/C catalysts. [Display omitted] • A plasma fabrication technique for synthesis of Pt-based nanoclusters with high dispersibility and small size was developed. • The average sizes of the prepared PtPd, PtRu and PtCu nanoclusters are 2.06 ± 0.68 nm, 3.66 ± 1.34 nm and 1.98 ± 0.7 nm. • The prepared Pt 3 Pd 4 /VR-P exhibits a low overpotential (19 mV) at 10 mA cm−2 and a high mass activity (5.4 A mg−1) for HER. [ABSTRACT FROM AUTHOR]

The gas diffusion layer (GDL) plays an important role in proton exchange membrane fuel cells (PEMFC) to support the catalytic layer, collect the current, conduct the gas and discharge the reaction product water. Titanium (Ti) can be one of the choices of GDL materials due to its high strength, low density and excellent corrosion resistance. Therefore, this paper investigated Ti substrate material for GDL and comparatively analyzed the changes in the contact angle of the GDL before and after hydrophobic treatment, analyzed the changes in the performance of the cell after different treatment processes, and measured the effect of compression force on the contact resistance of the cell. The results show that, after the selection of Ti felt as the substrate and the carbon plating process, the contact angle of the substrate layer and the microporous layer increased significantly, and the hydrophobicity of the GDL surface improved after carbon plating. The contact resistance of the Ti felt substrate was significantly reduced after carbon plating and was even lower than that of the C–H-060 substrate. Considering the importance of the hydrophobicity of GDL, acetylene black microporous layer coating is also needed to increase the contact angle of the GDL interface and improve the hydrophobicity of GDL. The hydrophobic treatment of MPL using Ti felt as the substrate can significantly improve the output performance of the cell at high current density, avoid flooding inside the cell, and increase the current density operating range of the cell. • The contact angle of Ti-GDL before and after hydrophobic treatment was studied. • The performance of Ti-GDL cell after different treatment processes were compared. • The effect of compression force on the contact resistance was analyzed. • The feasibility of Ti as a substrate for GDL in PEMFC was analyzed. [ABSTRACT FROM AUTHOR]

The present study focuses on the cogeneration of hydrogen (H 2) and solid carbon from microwave-driven methane pyrolysis in a fluidized bed of carbon pellets. Numerical simulations using a coupled gas-solid chemistry approach reveal that introducing microwave thermal effects improves methane conversion rate, H 2 selectivity, and carbon deposition rate. The chemical pathways analysis divulges that once the leading reaction for decomposing CH 4 into H 2 , i.e., CH 4 +H ↔ CH 3 +H 2 , is completed, the C 2 H 2 deposition mechanism onto the carbon pellets is the dominant pathway for the solid carbon production, indicating almost no carbon black (i.e., nanoparticles) formation. Carbon pellets provide abundant surface area for the conversion of C 2 H 2 to H 2 , enhancing H 2 selectivity in the resulting products. More importantly, the importance of more complex molecules, such as polycyclic aromatic hydrocarbons, greatly diminishes when using carbon pellets in the pyrolysis process, implying that smaller kinetic mechanisms are equally effective and desirable. • Cogeneration of H 2 and carbon from microwave-driven methane pyrolysis is studied. • Reaction CH 4 +H ↔ CH 3 +H 2 is the leading reaction in decomposing CH 4 and producing H 2. • Almost 100% of solid carbon comes from the addition of C 2 H 2 on the carbon pellets. • Carbon pellets suppress the formation of PAHs, resulting in no carbon black. • Microwave thermal effects exhibit positive impacts on H 2 and carbon production. [ABSTRACT FROM AUTHOR]

Carbon black nanoparticles (CBNPs) are widely distributed in the environment and are increasingly recognized as a contributor in the development of cardiovascular disease. A variety of cardiac injuries and diseases result from structural and functional damage to cardiomyocytes. This study explored the mechanisms of CBNPs-mediated myocardial toxicity. CBNPs were given to mice through intra-tracheal instillation and it was demonstrated that the particles can be taken up into the cardiac tissue. Exposure to CBNPs induced cardiomyocyte inflammation and apoptosis. In combination with in vitro experiments, we showed that CBNPs increased the ROS and induced mitochondria fragmentation. Functionally, CBNPs-exposed cardiomyocyte exhibited depolarization of the mitochondrial membrane potential, release of cytochrome c , and activation of pro-apoptotic BAX, thereby initiating programmed cell death. On the other hand, CBNPs impaired autophagy, leading to the inadequate removal of dysfunctional mitochondria. The excess accumulation of damaged mitochondria further stimulated NF-κB activation and triggered the NLRP3 inflammasome pathway. Both the antioxidant N -acetylcysteine and the autophagy activator rapamycin were effective to attenuate the damage of CBNPs on cardiomyocytes. Taken together, this study elucidated the potential mechanism underlying CBNPs-induced myocardial injury and provided a scientific reference for the evaluation and prevention of the CBNPs-related heart risk. [Display omitted] • CBNPs can be taken up into cardiomyocytes through intra-tracheal instillation and induce myocardial toxicity. • ROS mediates myocardial cell damage through disruption of mitochondrial quality control. • Inhibition of mitophagy triggers the inflammation and mitochondrial-dependent apoptosis in myocardial cell. [ABSTRACT FROM AUTHOR]

The most crucial goal is the improvement of Ultra High Temperature Ceramic (UHTC) fracture toughness without negatively impacting the ceramic high-temperature properties. Carbon nanostructures in UHTCs appear to be one of the most promising ways forward. The influence of reduced graphene oxide vs. carbon black on microstructure and properties of TiB 2 -SiC ceramics is studied. The composite ceramic samples with additive contents up to 7.4 wt% were manufactured via the reactive hot pressing of B 4 C-TiC-Si-reduced graphene oxide/carbon black precursors at 1850 °С and 30 MPa for 4 min. The sintered materials composition and structure were analysed with Raman spectroscopy, XRD, SEM, and TEM. Reduced graphene oxide (rGO) survives the hot-pressing procedure and, at lower concentrations, distributes inside the TiB 2 -SiC matrix in the form of separate sheets. However, at 7.4 wt%, the rGO was shown to agglomerate. The rGO improved the hardness, fracture toughness, and thermal conductivity of the TiB 2 -SiC by up to 16%, 20%, and 53%, respectively. The composite characteristics reached the values of H V = 26.1 GPa, K 1 C = 7.4 MPa∙m1/2, and k = 69 W/m∙K. Carbon black additive formed roughly equiaxial two micrometre inclusions and was not observed to impact the investigated properties. [ABSTRACT FROM AUTHOR]

• Size-resolved Effective density of submicron atmospheric particles in Shenzhen were measured online using DMA-CPMA-CPC combined system. • Bimodal distribution feature of particle effective density was identified, including a main density mode and a sub density mode, by bimodal Gaussian fitting. • Particle effective density exhibited a high occurrence frequency of bimodal distribution, and two density modes exhibited opposite size distribution trends. • Effective density variation was highly correlated with the proportion of OA, sulfates and BC. Effective density (ρ eff) is one of the most important physical properties of atmospheric particles, providing important references in exploring the emissions and aging processes of fresh particles. In this study, a combined system of differential mobility analyzer, centrifugal particle mass analyzer, and condensation particle counter was used to periodically measure the ρ eff of atmospheric particles in Shenzhen from Oct. 2021 to Jan. 2022. Results showed that the ρ eff of particles with various size presented a bimodal distribution, which could be divided into main density (ρ m , main peak, corresponding to relatively dense particles after aging) and sub density (ρ s , sub peak, corresponding to fresh particles). The occurrence frequencies of ρ s of particles with diameters of 50 and 80 nm were less than 20%, but were as high as about 40% of that with diameters from 120 to 350 nm. The ρ m showed increasing trend with the size of particles, while ρ s decreased as the increasing of the size of particles. The ρ eff on pollution day varied significantly with chemical compositions. The increasing of the proportion of sulfate could promote the increasing of ρ eff , while black carbon and organic matter caused opposite effects, which may be related to various factors, including the difference of the material density and morphology of various chemical components. The ρ eff of 50, 80 and 120 nm particles decreased considerably during the new particle formation event, indicating that organic condensation was an important contributor to new particle growth. [ABSTRACT FROM AUTHOR]

Microwave-assisted carbothermal reduction has been innovatively developed for the low-temperature synthesis of high-purity submicron TiB 2 powders. The thermodynamic research of TiO 2 -B 4 C-C system and relevant reactions showed that suitable excess addition of B 4 C was required to compensate for the boron source evaporation loss. The effect of excess addition of B 4 C (0 −15 wt%) and synthesis temperature (1350 −1550 °C) on the phase composition, purity, and morphology of the products have been investigated. Submicron TiB 2 powders (0.75 µm) with high-purity (0.36% residual C and 0.53% O) were successfully synthesized at 1450 °C for 20 min under microwave assistance with TiO 2 , excess 5 wt% B 4 C, and carbon black. Additionally, the as-synthesized TiB 2 powders after spark plasma sintering at 2000 °C for 15 min showed a relatively higher sinterability, namely increased at 7.7% relative density of sintered ceramic when compared with the commercially available powders owing to the lower O content and submicron-scale size. [ABSTRACT FROM AUTHOR]

A method for industrial production of nano-scaled WC powders has been proposed. In this work, WO 2.9 is subject to pre-reduction, followed by jet-milling treatment. The precursor is then mixed with carbon black by ball milling, and directly reduced-carbonized to nano-scaled WC powders. The WC powders prepared at different carbonization temperatures were made into alloys and micro drills, revealing the influence of powder properties on the microstructure and properties of the alloys through comparative analysis. The results indicate that when WO 2.9 powder is reduced at 700 °C for 1h and then jet-milled at a rotational speed of the grading wheel of 3500 rpm, the aggregates in the powder can be effectively broken, and the precursor powders with fine particle size and near-single phase can be obtained. In this way, the equipment exhibits relatively high productivity. By comparing the microstructure and properties of the alloy prepared from raw materials at different carbonization temperatures, it can be seen that if the carbonization temperature is too high, the average particle size of the powder increases and agglomeration appears in the microstructure. An increase in the average particle size of the powder will lead to an increase in the average grain size of the prepared alloys, thereby reducing the hardness and the wear resistance during service. In addition, the agglomerated particles in the powders can easily lead to abnormal WC grain growth in the microstructure of the prepared alloys, which reduces the bending strength. [ABSTRACT FROM AUTHOR]

For the reaction-formed graphite/SiC composites, the presence of cracks and poor mechanical properties seriously affect their reliability as wear resistant or sealing materials. In this work, a porous carbon preform was pressure formed first by carbon-composite-powder (PFC@G) and carbon black, impregnated with resin and carbonized subsequently, which can heal the micro-cracks, increased the strength of porous carbon preforms and finally reduce the reactivity of liquid Si and carbon during the reaction forming process. The results show that the modified porous carbon preform has a 4.8 % reduction in porosity and a 3.98 times increase in compressive strength. After reactive melt infiltration, the prepared graphite/SiC composites had a compact and isotropic structure and obtained the highest carbon content of 66.18 vol%. In addition, the coupling effect of the PFC@G size on the carbon content and mechanical properties of composites was studied. With the decreasing of the PFC@G size, the mechanical properties of the composites increased and the carbon content decreased. The sample with a carbon content of 48 vol% and a bending strength of 137 MPa exhibited excellent self-lubrication properties. [ABSTRACT FROM AUTHOR]

Carbon black has been successfully converted into silicon carbide by reacting it with SiO vapor at 1500 °C under Ar gas environment. The influence of reaction temperature, duration and Ar gas flow rate on the final product was examined. The structural and microstructural property of synthesized SiC was characterized using X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM). Micrographs of synthesized SiC showed that the final product was an agglomeration of SiC nano-powder of 50–500 nm size and nano-whiskers/fibres having a diameter of 50–500 nm and lengths in 0.1–10 μm depending on Ar gas flow rate. The higher conversion of C into SiC was observed at 1500 °C with Ar gas flow rate ∼250 ml/min. [ABSTRACT FROM AUTHOR]

Recently, there has been an increasing demand for high-voltage thermal batteries. FeF 3 has a high open-circuit voltage of 2.7 V and is gaining attention as a potential alternative. However, it involves the problem of a low electrical conductivity owing to the wide band gap (5.96 eV) and the generation of lithium fluoride (LiF), which is a discharge product in the conversion reaction. To address this issue, acetylene black with high conductivity is utilized to enhance the electrochemical activity of metal fluoride (FeF 3). At present, FeF 3 /AB is produced by low- and high-collision-energy ball milling. These are mechanical milling methods that involve different collision energies. High-collision-energy ball milling has been demonstrated to degrade the electrochemical performance owing to crystal deformation. In contrast, low-collision-energy ball milling has demonstrated the potential for application in thermal batteries by minimizing crystal deformation and enhancing the electrical conductivity. In this study, the amount of added carbon was optimized to enhance the performance of thermal battery materials. Both low- and high-collision-energy ball-milling processes exhibited remarkable thermal stability when 5.0 wt% carbon was added. However, the high-collision-energy ball-milling process did not effectively enhance the thermal cell performance because the electrical conductivity did not increase significantly. Therefore, FeF 3 /5.0 wt% AB produced by low-collision-energy ball milling exhibited remarkable thermal stability and electrical conductivity. This indicates its potential for use in thermal batteries. [ABSTRACT FROM AUTHOR]

To understand the effects of additives on the properties of rubber grades suitable for sealing applications in high-pressure H 2 gas infrastructure, five acrylonitrile butadiene rubber (NBR) vulcanizates with different fillers and curing agents are investigated. Structure-property relationships of these grades are correlated with the additives and properties required for high-pressure gas atmospheres are evaluated. Further, the influence of the exposure to high-pressure hydrogen, i.e., hydrogen uptake and morphological changes after exposure, is evaluated. With the addition of a silica filler and a coupling agent for improved filler-matrix interfaces, similar overall properties, e.g. crosslink density, tensile strength, and storage modulus are obtained, compared to a carbon black (CB) filled grade. Density reduction after hydrogen exposure is significantly higher for CB-filled NBR, indicating higher hydrogen uptake in CB-filled rubber compared to silica filled NBR grades, or slower gas desorption. However, CB-filled specimens show to be less prone to filler migration than the silica-filled samples. • Effects of NBR formulations on properties for high-pressure gas systems were tested. • Functionalized silica enhances typical properties to a comparable range like CB. • The balance of additives results in suitable RGD performance. • Silica filled NBR shows lower H 2 uptake compared to non-plasticized CB filled NBR. • Morphology of CB filled NBR is less affected by H 2 than silica filled grades. [ABSTRACT FROM AUTHOR]

Bioelectro-Fenton (BEF) utilizes microorganisms to generate electrons at the anode and transfer them to the cathode via an external circuit to generate hydrogen peroxide (H 2 O 2) and drive the Fenton reaction to produce OH•. Response surface methodology was used to optimize the ratio of nano zero-valent iron-containing biochar and conductive carbon black (nZVI-biochar/CCB) with the chitosan-coated on the surface of the cathode material to promote H 2 O 2 production and reduce the internal resistance of the BEF system. The BEF system using the optimized cathode catalysts showed a 2.6-fold increase in power density and a 2.03-fold increase in open-circuit voltage over the BEF reaction using graphite felt cathodes only. This finding demonstrated that the optimized cathode improved the capability of the cathode to receive electrons. The BEF system with the optimized cathodic catalyst completely removed 400 mg/L isopropanol within 24 h, and the treated wastewater was almost nonbiotoxic. [Display omitted] • Microbial fuel cells produce electricity to drive the electro-Fenton (EF) process. • Bioelectro-Fenton (BEF) process removes isopropanol from wastewater. • Optimization of cathodic catalyst ratio improves H 2 O 2 generation in the EF system. • BEF system with optimized cathodic catalyst enhances power and isopropanol removal. [ABSTRACT FROM AUTHOR]

• Comparison of portable black carbon monitors with standard aethalometer AE33. • The effect of ambient environment and built-in algorithms were investigated. • Suggestion on application scenario of each micro monitor proposed. Black carbon (BC) is associated with adverse human health and climate change. Mapping BC spatial distribution imperatively requires low-cost and portable devices. Several portable BC monitors are commercially available, but their accuracy and reliability are not always satisfactory during continuous field observation. This study evaluated three models of portable black carbon monitors, C12, MA350 and DST, and investigates the factors that affect their performance. The monitors were tested in urban Beijing, where portable devices running for one month alongside a regular-size reference aethalometer AE33. The study considers several factors that could influence the monitors' performance, including ambient weather, aerosol composition, loading artifacts, and built-in algorithms. The results show that MA350 and DST present considerable discrepancies to the reference instrument, mainly occurring at lower concentrations (0–500 ng/m3) and higher concentrations (2500–8000 ng/m3), respectively. These discrepancies were likely caused by the anomalous noise of MA350 and the loading artifacts of DST. The study also suggests that the ambient environment has limited influence on the monitors' performance, but loading artifacts and accompanying compensation algorithms can result in unrealistic data. Based on the evaluation, the study suggests that C12 is the best choice for unsupervised field measurement, DST should be used in scenarios where frequent maintenance is available, and MA350 is suitable for research purposes with post-processing applicable. The study highlights the importance of assigning portable BC monitors to appropriate applications and the need for optimized real-time compensation algorithms. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] The platinum catalysts based on carbon black and carbon nanotubes supports have been obtained via pulse alternating current technique. The synthesized Pt/C catalysts showed better electric transport characteristics and the carbon monoxide poisoning resistance in comparison with the commercial Pt/C owing to both the size of the platinum nanoparticles and their agglomeration on the support surface, and the morphology of the carbon support. [ABSTRACT FROM AUTHOR]

This study focused on improving SiC-Ti 3 SiC 2 composites fabricated through reactive melt infiltration (RMI) using TiSi 2 alloy to optimize their microstructure, mechanical, and corrosion properties. The results indicated that achieving a balance between the carbon black content and the porosity of the preforms led to a decrease in residual TiSi 2 and an increase in the content of the MAX phase in the composites. The composite, derived from a SiC60-C40 preform with 35% porosity, contained 76 vol% SiC, 22 vol% Ti 3 SiC 2 , and 2 vol% TiSi 2. The "time window" based on two reactions specific to the TiSi 2 and C facilitates the creation of infiltration channels and the reduction of residual TiSi 2. With minimal residual TiSi2, the composite exhibited a flexural strength of 395 MPa, a fracture toughness of 5.24 MPa·m1/2, and maintained over 70% of its original strength after thermal shock below 1200ºC. Enhanced corrosion resistance was attributed to a protective MgTiO 3 layer. [ABSTRACT FROM AUTHOR]

Dodecahydro-N-ethylcarbazole (12H-NEC) is considered as a highly promising liquid organic hydrogen carrier, but its commercial application is constrained by the requirement of large amounts of precious metal catalysts for dehydrogenation. Herein, Pd nanoclusters with an average particle size of 1.1 nm supported on amine groups modified carbon blacks (Pd/N–C HNO3) are developed to efficiently catalyze the dehydrogenation of 12H-NEC with a low loading of Pd (2.2 wt%, 0.12 mol%). Induced by the nitrogen doping in the carbon black, the d- band center of the Pd (111) surface shifts from −1.64 eV to −1.53 eV, resulting in the electron-deficient structure of thus-formed Pd nanoclusters owing to the electron transfer from Pd to N atoms and uniform distribution of Pd nanoclusters inside of carbon blacks. This electron transfer effectively tunes Pd0:Pdδ+ ratio for enhancing the adsorption of reactant species of 12H-NEC on the surface of Pd nanoclusters and hence facilitates the catalytic role of Pd nanoclusters in enhancing the hydrogen desorption performance of 12H-NEC. As a result, every step of the dehydrogenation of 12H-NEC under the catalysis of Pd nanoclusters on the nitrogen-doped support exhibits lower ΔG values compared to the non-doped support, which provides direct evidence to the important role of the nitrogen doping of the catalyst support in improving the dehydrogenation performance of 12H-NEC on the Pd surface. Therefore, a hydrogen release capacity of 5.60 wt% with 100% conversion and a selectivity of 90% could be obtained for 12H-NEC under the catalysis of Pd nanoclusters supported on amine-functionalized carbon black at 453 K with a low precious metal dosage (0.12 mol%). [Display omitted] •Pd nanoclusters with an average particle size of 1.1 nm supported on amine groups modified carbon blacks are developed. • A hydrogen release capacity of 5.60 wt% is obtained for 12H-NEC with an ultralow Pd dosage (0.12 mol%). • A H 2 release amount of 5.49 wt% with a capacity retention of 96% is achieved for 12H-NEC after five cycles for 40 h. • The d- band center of the Pd (111) surface shifts from −1.64eV to −1.53eV upon nitrogen doping. • DFT calculations reveal that ΔG for the dehydrogenation of 12H-NEC by the catalyst is decreased upon nitrogen doping. [ABSTRACT FROM AUTHOR]

Low-carbon conversion of hydrocarbon fuels and feedstocks, as well as the macroscopic production of H 2 , are central focus in the advancement of high-value and efficient conversion of CH 4. The effects of Ar addition ratio, discharge power and temperature on the results of plasma methane cracking were investigated on a dielectric barrier discharge (DBD) plasma experimental system. The results show that the addition of Ar can improve the methane conversion, and the optimal ratio of CH 4 conversion to H 2 production after the effect is CH 4 : Ar = 1:1, at which the methane conversion reaches 49.62% and the H 2 selectivity reaches 52.66%. The plasma at 25 °C can make the methane conversion close to the effect of catalytic cracking at 600 °C, while the H 2 selectivity is lower, the H 2 generation is 32.59% lower than the latter, and the products have more C 2 –C 4 hydrocarbon impurities. The solid byproduct resulting from the DBD plasma cracking of methane primarily consisted of carbon black, possessing an average particle size of 62.21 nm. The incorporation of Ar and the amplification of power augment the CH* radical intensities, which suggests both conditions contribute positively to the dissociation of the CH 4 molecule. [Display omitted] • The optimal ratio of CH 4 to Ar stands at 1:1. • Plasma operating at 25 °C can mimic the catalytic thermal cracking effect at 600 °C. • The generation of the solid-phase product, carbon black is induced by the plasma. • An increase in the C 2 –C 4 product is observed under plasma activity. [ABSTRACT FROM AUTHOR]

A set of (Ti 0.2 Zr 0.2 Hf 0.2 Ta 0.2 Nb 0.2)C high-entropy carbide (HEC) ceramic samples were produced via spark plasma sintering (SPS) at a temperature of 1900 °C utilizing synthesized carbide powders. The carbide powders were synthesized via carbothermal reduction and derived from various carbon sources including carbon black, carbon microspheres, flake graphite, and graphitic carbon spheres. The impact of the different carbon sources was evaluated, for the first time, on the HEC's phase composition, microstructure, mechanical properties, and oxidation behavior. Results show that the HEC prepared using graphitic carbon spheres had a single-phase rock salt structure, with an average grain size of approximately 770 nm, which was smaller than that of HEC samples derived from the other carbon sources, due to its lower oxygen content, better dispersion, and higher chemical reactivity. Additionally, these HEC samples manufactured using graphitic carbon spheres exhibited 98.9% relative density, 20.39 GPa hardness, 4.5 ± 0.6 MPa·m1/2 fracture toughness, and excellent oxidation resistance. Therefore, by optimizing the reactivity and dispersion of carbon sources, high-performance HEC ceramics can be created. [ABSTRACT FROM AUTHOR]

The CeO 2 catalyst is commonly utilized in diesel particulate filter (DPF) to promote soot regeneration. It is necessary to give a particular attention to the performance of hydrothermal aging and the effect on DPF regeneration characteristics. Based on the fixed-bed test bench, the gas and particle emission characteristics of carbon black (PU) oxidation following hydrothermal aging and sieving treatment of CeO 2 are investigated under a 3% water concentration condition. CeO 2 is subjected to characterization and analysis combined with X-ray Photoelectron Spectroscopy (XPS), Electron Spin Resonance Spectroscopy (ESR), X-ray Powder Diffraction (XRD), and Scanning Electron Microscopy (SEM). The results indicate that the addition of fresh CeO 2 proves beneficial in improving the oxidation efficiency (η) of PU, reducing CO emission and the total average particle number (PN). Meanwhile, CO 2 emission rapidly increases. After hydrothermal aging, the average catalyst size and agglomeration degree of CeO 2 increase, resulting in an increase in lattice defects and bulk oxygen vacancies (V O-b). The reduction of surface oxygen vacancies (V O-s) plays a dominant role in the catalytic oxidation process of PU, leading to a decrease in η and CO 2 emission, while CO increase; And the contact mode between CeO 2 and PU, as well as alterations in the microstructure of CeO 2 , consequently contributing to hindering particle movement and reducing total PN. Furthermore, the sieving treatment of catalyst increases particle emission, but significantly promotes the η and reduces harmful gas CO. This research establishes a theoretical and experimental foundation for enhancing the hydrothermal stability of catalysts and controlling particle emission at the DPF outlet. [Display omitted] [ABSTRACT FROM AUTHOR]

The (W,Mo,Ta,Nb,Ti)(C,N) high-entropy carbonitride powders were synthesized by the carbothermal reduction nitridation method, utilizing equimolar proportions of either graphite or carbon black. The subsequent utilization of these pre-synthesized powders yielded carbonitride ceramics after spark plasma sintering. The choice of carbon source played an important role in the microstructure, phase compositions and mechanical properties. By employing carbon black with its fine particle size and high reactivity, the synthesized powder maintained finer size, narrow powder size distribution (350 ± 12 nm) and have less free-carbon (∼0.032 wt%), which contributed to the high hardness (26.8 ± 1.4 GPa) of the sintered ceramic. Conversely, utilizing graphite with its larger particle size and lower reactivity would increase the fraction of free-carbon, leading to the deterioration of the ceramic's performance. [ABSTRACT FROM AUTHOR]

SiBCN ceramics were prepared by a novel inorganic method: the in situ reaction of amorphous SiBON and C. Differences in the mechanical and ablation properties of composites prepared from flake graphite and carbon black (denoted as C f /CGZ and C f /CBZ, respectively) were compared to find a suitable carbon source. The results showed that flake graphite is the optimal carbon source. The fracture toughness of the C f /CGZ composite was 9.1 ± 0.4 MPa·m1/2, which is 23.0% higher than that of the C f /CBZ composite. This is because the flake graphite promoted crack deflection. Furthermore, after exposure to a plasma flame with a heat flux of 6.68 MW/m2 for 300 s, the mass and linear ablation rates of the C f /CGZ composite are 0.39 mg/s and − 0.19 µm/s, respectively, which is a decrease of 22.00% and 64.81%, respectively, as compared to those of the C f /CBZ composite. This is because of the directional distribution of flake graphite, which improved the thermal conductivity, reduced the ablation surface temperature, and facilitated the formation of a dense ZrO 2 /SiO 2 layer as an anti-ablation barrier. [ABSTRACT FROM AUTHOR]

A reliable and compact chemical mechanism of gas-phase methane pyrolysis leading to formation of large polycyclic aromatic hydrocarbon (PAH) molecules has been developed. This model is designed for studies of carbon nanostructure synthesis such as carbon black and graphene flakes, including soot growth kinetics. Methane pyrolysis with carbon nanostructure synthesis is a two-stage process where conversion of CH 4 to C 2 H 2 precedes the growth of PAH molecules from acetylene. We present a single chemical mechanism that accurately describes both stages. We have constructed a compact and accurate chemical mechanism capable of modeling both stages of methane pyrolysis based on the ABF [1] mechanism which was expanded with the most prominent reaction pathways from the mechanism by Tao [2] for small PAH molecules and HACA pathways for larger PAH molecules, up to 37 aromatic rings. The resulting mechanism was validated through comparison to multiple available sets of experimental data. Good agreement with the experimental data for both processes was obtained. Performance of the mechanism was tested for pyrolysis of methane-rich mixtures under long residence times leading to abundant formation of PAH molecules. It is shown that the inclusion of larger PAH species (up to A37) in the chemical mechanism is important for accurate prediction of the fraction of carbon converted to PAH molecules and, correspondingly, the residual fraction of acetylene in the mixture. The mechanism file is available upon request. [Display omitted] • Compact and accurate chemical mechanism for methane pyrolysis was assembled. • The mechanism covers both stages of methane pyrolysis: formation of C 2 H 2 and PAH. • The mechanism incorporates large PAH molecules up to 37 aromatic rings (A37). • Good agreement with the experimental data was obtained. [ABSTRACT FROM AUTHOR]

• Carbon black (CB) was successfully prepared from spent tyre pyrolysis oil (STPO). • CB yield decreases with increasing temperature, residence time and O 2 /Feed ratio. • Operating conditions dictate a trade-off between CB yield and carbon content. • Temperature and O 2 /Feed ratio show strong impact on CB yield and carbon content. • CB_STPO is richer in surface oxygen functionality than heavy residue fraction CB. Preparation of carbon black (CB) by partial oxidation of the spent tyre pyrolysis oil (STPO) and its heavy residue fraction (HRF) was systematically studied using a lab-scale drop tube furnace. The effect of furnace operating temperature (T : 1100 to 1400 °C), residence time (t r : 5 to 60 s) and oxygen to feed ratio (O/F : 174 to 732) on the yield and quality of CB was examined using the response surface methodology (RSM). T was shown to have the most significant influence on CB yield and properties. While the CB yield was also influenced by t r , the quality was more sensitively dependent on T and O/F. The predicted optimal t r and O/F were approximately the same for both feedstocks (60 s and 174, respectively). However, T was higher for the HRF feedstock (1368 °C) than the STPO feedstock (1331 °C) due to the abundance of more viscous heavy hydrocarbons in HRF. Validation experiments under the aforementioned conditions demonstrated the models' ability to predict responses accurately. The CB from both feedstocks had low contents of ash (<0.03%), volatiles (∼0.5%), sulphur (<0.7%), and high carbon (≥95%). The BET surface area and average primary particle size for CB from STPO and HRF were comparable to those of commercial CBs from fossil fuel feedstock. The CB from HRF had a higher carboxyl oxygen functional group (18%) compared to the CB from STPO (∼13%) and commercial CB (<5%). [ABSTRACT FROM AUTHOR]

Emissions from biomass burning challenge efforts to curb air pollution in cities downwind of fire-prone regions, as they contribute large amounts of brown carbon (BrC) and black carbon (BC) particles. We investigated the patterns of BrC and BC concentrations using Aethalometer data (at λ = 370 and 880 nm, respectively) spanning four years at a site impacted by the outflow of smoke. The data required to be post processed for the shadowing effect since, without correction, concentrations would be between 29% and 35% underestimated. The BrC concentrations were consistently higher than the BC concentrations, indicating the prevalence of aerosols from biomass burning. The results were supported by the Ångström coefficient (Å 370/880), with values predominantly larger than 1 (mean ± standard deviation: 1.25 ± 0.31). Å 370/880 values below 1 were more prevalent during the wet season, which suggests a contribution from fossil fuel combustion. We observed sharp BrC and BC seasonal signals, with mean minimum concentrations of 0.40 µg/m3 and 0.36 µg/m3, respectively, in the wet season, and mean maximum concentrations of 2.05 µg/m3 and 1.53 µg/m3 in the dry season. The largest concentrations were observed when northerly air masses moved over regions with a high density of fire spots. Local burning of residential solid waste and industrial combustion caused extreme BrC and BC concentrations under favourable wind directions. Although neither pollutant is included in any ambient air quality standards, our results suggest that transboundary smoke may hamper efforts to meet the World Health Organization guidelines for fine particles. [ABSTRACT FROM AUTHOR]

Ships and other mobile pollution sources emitted massive ultrafine and low-resistivity particles containing black carbon (BC), which were harmful to human health and were difficult to capture by conventional electrostatic precipitators (ESPs). In this study, nanoscale carbon black was adopted as simulated particles (SP) with similar physicochemical properties for black carbon emitted from ships (SP-BC) to investigate the feasibility of using an ESP with square-grooved collecting plates for the removal of SP-BC at low backpressures. The increased applied voltage significantly improved the total collection of SP-BC whereas may also promote the conversion of relatively larger particle size SP-BC into nano-size below 20 nm. The outlet number concentration of SP-BC under 27 kV at 130°C was three times that of the inlet. While the reduction of the flow rate could strengthen the capture of SP-BC below 20 nm, and under the combined action of low flow rate and maximum applied voltage, the collection efficiency of 20-100 nm SP-BC could exceed 90%. In addition, the escape and capture characteristics of SP-BC under long-term rapping were revealed. The square-grooved collecting plate could effectively restrain the re-entrainment of collected SP-BC generated by rapping, and the nanoscale SP-BC was trapped in the grooves after rapping. The results could provide insights into the profound removal of massive nanoscale black carbon emissions from mobile sources. [ABSTRACT FROM AUTHOR]

SiC reticulated porous ceramics have been widely utilized as filters in the smelting industry. To address the problem of hollow ceramic struts and improve the strength and thermal shock resistance of SiC reticulated porous ceramics, a one-step coating process was carried out using slurries with SiC, metallic Si and various carbon sources (carbon spheres, carbon black, and flake graphite). The effect of the carbon sources on the rheological behavior of the coating slurries was investigated, as well as the relationship between the rheological behavior of the slurries and the structure of the green bodies. The hollow struts and flaws resulting from the combustion of polymer templates were then filled with SiC whiskers formed by the reaction between Si and carbon sources during heating. Among the carbon sources, the carbon spheres significantly stimulated the growth of the SiC whiskers, which filled the voids and flaws. After heating at 1550 °C, the SiC reticulated porous ceramics prepared with Si and carbon spheres reached a porosity of 80%, compressive strength of 1.85 MPa, and residual compressive strength rate of 81%. In industrial tests, the fabricated SiC reticulated porous ceramics were used as filters to effectively remove inclusions in molten copper. Importantly, the structure of the SiC filters remained intact after use. [ABSTRACT FROM AUTHOR]

To improve the dispersion of SiC nanowires in ceramic matrix, SiC/MgAl 2 O 4 composite powders containing SiC nanowires were synthesized by combustion synthesis with Mg, Al, silica fume, carbon black as raw materials, while ferrocene was used as catalyst. The effects of Al/Mg (molar ratio) on the content and aspect ratio of SiC nanowires were studied. The mechanism of combustion reaction was investigated by combustion quenching method, and the growth mechanism of SiC nanowires was discussed. The results showed that the main phases of all specimens are SiC and spinel, and the content and aspect ratio of SiC nanowires increased firstly and then decreased with the increase of Al/Mg. The SiC nanowires showed the highest content (6.1%) and maximum aspect ratio (200) in the product when Al/Mg = 4. SiC and spinel generated in reaction zones, and the generation of SiC nanowires began at high temperature reaction zone. In addition, the growth mechanism of SiC nanowires was verified to be VLS and SLGS mechanism. [ABSTRACT FROM AUTHOR]

The present study shows that Ti 2 AlC and V 2 AlC could be synthesized by carburization of special precursor alloys. The initial Ti and V were hydrogenated, milled, and then mixed with Al particles. The prepared mixtures were annealed under vacuum and the temperature of 1000 °C was sufficient for alloy formation. The produced Ti 2 AlH x and V 2 AlH x alloys were brittle, which enabled crushing and mixing with carbon black. The obtained powders were heated under vacuum to nucleate the MAX phases. The annealing at 1100 °C was optimal because at lower and higher values of temperature either the carburization process was not complete or phase decomposition was observed. Additional experiments for synthesis of layered ceramics from the mixtures of TiH x /VH x , Al, and C were characterized with a slower reaction kinetics. The analysis of isothermal oxidation demonstrated smaller exothermic effects for Ti 2 AlH x compared to TiH x at 200–600 °C, while V 2 AlH x had lower intensities at 200–400 °C but higher at 500–600 °C with respect to VH x. [Display omitted] [ABSTRACT FROM AUTHOR]

Developers of direct carbon fuel cell (DCFC) technology seek to convert carbon to a pure or highly concentrated carbon dioxide stream that could ultimately be transported and sequestered. Carbon black produced by natural gas cracking processes is very pure and is therefore a candidate for use in DCFCs. In this study the performance of As received and Treated carbon blacks are compared in a planar cell configuration. At a more viable operating temperature of 750 °C, the As received carbon was found to produce a peak power density of 51 mW/cm2 at a current density of 104 mA/cm2. The performance then increased to 105 mW/cm2 at a current density of 145 mA/cm2 at 850 °C. Acid treatment of the carbon was found to improve performance of the DCFC at 750 °C by 35% (69 mW/cm2 at 160 mA/cm2) and only by 5% at 850 °C (111 mW/cm2 at 201 mA/cm2). • A commercial carbon black was used to fuel a planar, direct carbon fuel cell (DCFC). • An acid treatment method applied to the carbon black increased its wettability. • A DCFC output higher power density with Treated than with As received carbon black. [ABSTRACT FROM AUTHOR]

A method for producing hydrogen from liquid benzene without CO 2 generation using plasma is proposed. A liquid plasma was emitted from the liquid reactant to crack liquid benzene to produce hydrogen. The only gaseous product was H 2 and no CO 2 was formed. Carbon crystals were produced as a solid product. To increase the decomposition efficiency of liquid benzene and the efficiency of hydrogen production, perovskite was applied as a catalyst. The reaction produced nano-sized carbon particles with hydrogen as the main product without impurities. The crystal size of carbon black was very small (<10 nm) and uniform. The carbon products were similar in crystal shape and size regardless of the reaction time. Liquid benzene is decomposed by active species in the liquid plasma to produce hydrogen and carbon without catalyst injection. When the perovskite catalyst was applied to the reaction using liquid plasma, the hydrogen production rate and carbon yield were significantly increased. Liquid benzene simultaneously produces hydrogen and carbon black through a decomposition reaction by liquid plasma. The LPP cracking process of liquid benzene can be evaluated as a 'green hydrogen' production technology that does not generate CO 2. [Display omitted] • A method was proposed for producing hydrogen from the decomposition of benzene using plasma. • Liquid benzene was decomposed into hydrogen and carbon by liquid plasma and photocatalyst. • Perovskites were applied as a photocatalyst to increase hydrogen production efficiency. • The products were hydrogen gas and carbon nanoparticles in this reaction, no CO 2 is formed. • Application of the perovskite catalyst significantly increased hydrogen production and carbon yield. [ABSTRACT FROM AUTHOR]

The synthesis of ammonia via electrochemical nitrogen reduction reaction (NRR) provides an attractive alternative approach to the traditional Haber-Bosch process. In this regard, a one-step hydrothermal method was adopted to synthesize a bimetallic oxide， ferric molybdate (Fe 2 (MoO 4) 3), coated with carbon black on the surface (denoted as Fe 2 (MoO 4) 3 /C). The carbon black coating minimizes aggregation of Fe 2 (MoO 4) 3 , leading to increased electrochemical active sites for NRR. Additionally, this coating improves the electrical conductivity of Fe 2 (MoO 4) 3 thereby accelerating electron transfer between carbon black and Fe 2 (MoO 4) 3 , which is beneficial to charge transfer and enlarge the electrochemical active surface areas. At a potential of −0.4 V RHE (vs. reversible hydrogen electrode, RHE), the ammonia yield achieved was up to 51.76 μg h−1 mg cat −1, with a Faradaic efficiency of 90.63% at −0.35V RHE. Impressively, this electrocatalyst exhibited excellent cycle stability and durability. Fe 2 (MoO 4) 3 /C electrocatalyst was prepared via a one-step hydrothermal method and demonstrated to be a highly efficient non-noble metal catalyst towards electrocatalytic NRR. The obtained Fe 2 (MoO 4) 3 /C gives an NH 3 yield rate of 51.76 μg h−1 mg cat −1 at −0.4 V RHE and FE of 90.63% at −0.35 V RHE in 0.1 M Na 2 SO 4 solution, which is much higher than that of the contrast Fe 2 (MoO 4) 3 sample. [Display omitted] • Fe 2 (MoO 4) 3 /C composite electrocatalyst is reasonably designed and synthesized. • Fe 2 (MoO 4) 3 /C shows excellent stability for electrocatalytic nitrogen reduction in 0.1 M Na 2 SO 4 electrolyte. • The excellent NRR activities of Fe 2 (MoO 4) 3 /C own to the enhanced electron transfer and enlarged ECSA. [ABSTRACT FROM AUTHOR]

A Pd–Ni ellipsoidal nano-alloy catalyst with a long diameter of 5 ± 0.1 nm and short diameter of 3 ± 0.1 nm supported on carbon black (PdNi EN/CB) was successfully prepared via a facile one-pot synthesis route. During the synthetic process, cetyl trimethyl ammonium chloride (CTAC) was used as a structure-directing agent, which induced the ellipsoidal morphology. As compared with commercial Pt/C, Pd/C and Pd–Ni catalyst without special morphology supported on carbon black (PdNi NW/CB), PdNi EN/CB demonstrated both ultrahigh catalytic activity towards oxygen reduction reaction (ORR) and favorable long-term durability in alkaline solutions. According to X-ray photoelectron spectra (XPS) analysis and density functional theory (DFT) calculation results, a down-shift of the Pd d-band center, which weakens the adsorption strength for oxygen-containing species, along with a reaction path closer to the ideal free energy due to the small particle size and special morphology of Pd–Ni ellipsoidal nano-alloys contribute to the excellent activity of the PdNi EN/CB catalyst. [Display omitted] • A Pd–Ni ellipsoidal nano-alloy catalyst supported on carbon black was prepared. • Formation of ellipsoid is due to the addition of CTAC as a structure-directing agent. • PdNi EN/CB has superb catalytic activity for ORR and favorable durability in KOH. • A down-shift of d-band center owing to special morphology leads to the high activity. • The reaction path of PdNi EN/CB is closer to the ideal free energy. [ABSTRACT FROM AUTHOR]

A sensitive acetylene black modified carbon paste electrode was fabricated for the determination of trace mercury ions in water samples. Nitric acid treatment of acetylene black (TAB) produced a porous structure with large surface area and defects, improving its performance as an electrode modifier. Under optimized conditions, the TAB/CPE showed good selectivity and sensitivity towards mercury ions. The peak current exhibited a linear relationship with mercury ion concentration from 10 nM to 0.1 mM, with a detection limit of 8.8 nM. The enhanced sensitivity results from a synergistic effect between the properties of TAB and carbon paste. The porous structure, large surface area and defects in TAB improve mercury ion adsorption and electron transfer kinetics. Meanwhile, the carbon paste provides a stable and conductive electrode base. The developed sensor showed good stability, repeatability and reproducibility, as well as acceptable recovery results when applied to detect mercury ions in simulated water samples. This simple and rapid electrochemical method holds potential for the determination of trace mercury ions in environmental water samples. [ABSTRACT FROM AUTHOR]

The association between air pollution and risk of respiratory tract infection (RTI) in adults needs to be clarified in settings with low to moderate levels of air pollution. We investigated this in the Danish population between 2004 and 2016. We included 3 653 490 persons aged 18–64 years in a nested case-control study. Exposure was defined as the average daily concentration at the individual's residential address of CO, NO X , NO 2 , O 3 , SO 2 , NH 3 , PPM 2.5 , black carbon, organic carbon, mineral dust, sea salt, secondary inorganic aerosols, SO 4 2-, NO 3 -, NH 4 +, secondary organic aerosols, PM 2.5 , and PM 10 during a 3-month exposure window. RTIs were defined by hospitalization for RTIs. Incidence rate ratios (IRRs) and 95% CIs were estimated comparing highest with lowest decile of exposure using conditional logistic regression models. In total, 188 439 incident cases of RTI were identified. Exposure to most air pollutants was positively associated with risk of RTI. For example, NO 2 showed an IRR of 1.52 (CI: 1.48–1.55), and PM 2.5 showed an IRR of 1.45 (CI: 1.40–1.50). In contrast, exposure to sea salt, PM 10 , NH 3 , and O 3 was negatively associated with a risk of RTIs. In this nationwide study comprising adults, exposure to air pollution was associated with risk of RTIs and subgroups hereof. Sea salt, PM 10 , NH 3 , and O 3 may be proxies for rural areas, as the levels of these species in Denmark are higher near the western coastlines and/or in rural areas with fewer combustion sources. [ABSTRACT FROM AUTHOR]

The purity of TiB 2 is unsatisfactory (<97%) even when synthesized at a high reaction temperature (∼1800 °C) using the carbothermal method. In this work, a thermodynamic investigation with an experimental approach was conducted to optimize the reaction parameters to improve TiB 2 purity and confirm the carbothermal reaction mechanism utilizing H 3 BO 3 , C, and highly-reactive metatitanic acid as raw materials. High-purity TiB 2 a with low level of impurities (0.27% C and 0.56% O) was successfully synthesized at 1550 °C for 60 min with carbon black as the optimal reductant at a molar ratio of 1:2.5:5.25 (Ti:B:C). Based on the thermodynamic and experimental results, the TiB 2 -synthesis mechanism was confirmed to involve TiC as the precursor for TiB 2 formation, which then reacted with liquid B 2 O 3 and C to form TiB 2. Additionally, the as-synthesized TiB 2 powders were spark-plasma sintered to a relative density of 96.5% with fine grains at 1800 °C for 10 min under a pressure of 50 MPa without additives, mainly owing to the lower O content. This study provides a feasible route for large-scale production of high-purity TiB 2. [ABSTRACT FROM AUTHOR]

For the reaction-formed graphite/SiC composites, the drastic consumption of vast amounts of carbon phase by violent reaction with liquid silicon is a prominent problem during reactive melt infiltration, resulting in low carbon content of the composites. To retain adequate graphite phase, in this work, hybrid carbon powders (PFC@G), adhered with nano carbon black via a binder, were employed as carbon sources for fabricating the graphite/SiC composites with high carbon content. The mechanism of retaining graphite phase in the graphite/SiC composites by reaction-formed SiC layer with nano carbon black was investigated. The results indicate that a carbon content of 43.03 vol% was obtained for graphite/SiC composites when the content of nano carbon black is 10 wt% in the carbon source. The microscopy results revealed that the PFC@G was protected effectively by the condense layer with fine SiC grains generated via the reaction between nano carbon black and liquid silicon. [ABSTRACT FROM AUTHOR]

• BR/VMQ blends filled with carbon black are promising compounds for Mars environment applications. • Radiation resistance of the CBs-filled BR/VMQ blends is very high allowing for long-term utilization on Mars. • Low glass transition temperatures of the BR and VMQ allow the application of the blends in most of Mars' temperature range. A growing interest in Mars exploration calls for new solutions as an increasing mass of rovers causes their metal alloy wheels to experience serious damage. Martian conditions including temperatures as low as −120 °C and destructive ionizing radiation effectively rule out rubber materials currently used on Earth. This study aims to design and test rubber compounds capable of withstanding harsh Martian conditions while providing good damping properties and remaining elastic in extremely low temperatures. The prepared compounds contained two elastomers – butadiene (BR) and silicone rubber (VMQ) – which both show appropriately low glass transition temperatures. Mixing of the rubbers provided blends combining properties desirable for Martian applications. For better miscibility and chemical coupling trimethylolpropane tris(3-mercaptopropionate) compatibilizer containing three thiol groups was incorporated. Additionally, to improve mechanical properties and as a free radical scavenger, carbon black (CB) fillers were used. The properties of compounds with and without the addition of the compatibilizer were evaluated. Obtained data shows the great potential of the BR/VMQ blends for future Martian applications. [ABSTRACT FROM AUTHOR]

In this experimental study , two units are held and studied: the traditional tubular solar still (TTSS) and the developed tubular solar still (DTSS). The influence of a developed solar parabolic concentrator (DSPC) employed with carbon black nanoparticles (CBNs), a V-corrugated Aluminum basin (VCAB), and wick martial on the thermal efficiency and productivity was investigated in four cases: (Case A): DTSS with DSPC, (Case B): DTSS with DSPC and CBNs, (Case C): DTSS with DSPC and V-corrugated Aluminum basin (VCAB), and CBNs, (Case D): DTSS with DSPC and VCAB and CBNs by using factors such as air temperature, cover temperature, water temperature, air speed, and sun radiation. It was found that case four was the best case, where it had the highest hourly efficiency at 18:0 for each of the traditional unit and the modified unit, and that the energy efficiency, exergy efficiency, and daily productivity increased by 129.8%, 365.44%, and 120.536%, respectively, compared to the traditional unit, its cost, which was 0.026$, was reduced by 23%. [ABSTRACT FROM AUTHOR]

Reaction-bonded SiC is a ceramic with excellent thermal properties, good corrosion resistance and the characteristic of near-net-shape manufacturing. However, the poor fracture toughness of free Si limits the applications of reaction-bonded SiC. In this study, TiC was added to reaction-bonded SiC and reacted with free Si to form Ti 3 SiC 2. The effects of TiC and carbon black on the mechanical properties of reaction-bonded SiC were investigated. The results demonstrated that the in-situ formation of Ti 3 SiC 2 and decrease in the content and size of free Si improved the mechanical properties of reaction-bonded SiC ceramics. The mechanical properties of TiC-added reaction-bonded SiC with 17.5 wt% carbon black were superior to those of TiC-added reaction-bonded SiC with 15 wt% carbon black. Moreover, increasing the TiC content of reaction-bonded SiC with 17.5 wt% carbon black from 0 to 7.5 wt% caused an increase in its bending strength from 183.92 to 424.43 MPa and an increase in fracture toughness from 3.7 to 5.24 MPa m1/2. [ABSTRACT FROM AUTHOR]

To select suitable high-temperature foaming agents, SiO 2 –Al 2 O 3 –CaO-based foam ceramics (SACFC) were successfully prepared with different foaming agents based on phosphorus tailings and coal gangue. The effects of high-temperature foaming agents (CaCO 3 , carbon black, MnO 2 and Fe 2 O 3) on the microstructure and compressive strength of the SACFC were investigated, and the corresponding foaming mechanism was revealed. The results indicated that CaCO 3 could increase the porosity of SACFC due to high-temperature decomposition. However, the precipitation of needle-like anorthite reduced the mechanical properties. Because the high-temperature oxidation temperature of carbon black was lower than the molten phase formation temperature, bubbles floated up and gathered on the surface of SACFC, leading to a decrease in strength. The continuous release of O 2 from MnO 2 during the sintering process promoted the growth and aggregation of large pores, which was detrimental to the strength. The CO 2 generated by the redox of Fe 2 O 3 by CO/C was the main factor for the foaming of SACFC. During the high-temperature foaming, the synergy effect of Fe2+ and Fe3+ promoted the formation of a uniformly distributed pore structure. When 2 wt.% Fe 2 O 3 was added, SACFC obtained the optimal comprehensive performance with bulk density and compressive strength of 0.78 g/cm3 and 3.50 MPa. [ABSTRACT FROM AUTHOR]

The coalescence behavior of soot and carbon black has not been so much discussed. The coalescence rate was obtained from the previous experimental results which measured the decrease in mobility diameter by re-heating with tandem differential mobility analyzer. Employing the rate expression used for sintering metallic and inorganic nanoparticles, it was found that the ease of coalescence varied with particle size. It was also suggested that the mechanism of coalescence may differ depending on the temperature. A model of coalescence kinetics based on crystallinity could not represent experimental coalescence kinetics. [Display omitted] • Estimation of coalescence rate constants for carbon nanoparticles. • Conventional formula greatly overestimates coalescing rate. • Coalescence was multi-staged, different mechanism from metal nanoparticles. [ABSTRACT FROM AUTHOR]

Black carbon (BC) aerosols in the atmosphere play a significant role in climate systems due to their strong ability to absorb solar radiation. The lifetime of BC depends on atmospheric transport, aging and consequently on wet scavenging processes (in-cloud and below-cloud scavenging). In this study, sequential rainwater samples in eight rainfall events collected in 2 mm interval were measured by a tandem system including a single particle soot photometer (SP2) and a nebulizer. The results showed that the volume-weighted average (VWA) mass concentrations of refractory black carbon (rBC) in each rainfall event varied, ranging from 10.8 to 78.9 µg/L. The highest rBC concentrations in the rainwater samples typically occurred in the first fraction from individual rainfall events. The geometric mean median mass-equivalent diameter (MMD) decreased under precipitation, indicating that r BC with larger sizes was relatively aged and preferentially removed by wet scavenging. A positive correlation (R 2 = 0.73) between the VWA mass concentrations of r BC in rainwater and that in ambient air suggested the important contribution of scavenging process. Additionally, the contributions of in-cloud and below-cloud scavenging were distinguished and accounted for 74% and 26% to wet scavenging, respectively. The scavenging ratio of rBC particles was estimated to be 0.06 on average. This study provides helpful information for better understanding the mechanism of rBC wet scavenging and reducing the uncertainty of numerical simulations of the climate effects of rBC. [Display omitted] [ABSTRACT FROM AUTHOR]

Geopolymer has potential advantage in electrical conductivity. The conductive and mechanical properties of engineered geopolymer composite (EGC) with carbon fiber (CF) and nano-carbon black (NCB) were studied respectively in this paper. Firstly, the percolation thresholds of CF and NCB were determined, and then the effect of curing age, moisture content and temperature on the conductivity were analyzed. The fluidity, compressive and flexural strengths and tensile ductility were also analyzed. Finally, the conductive behaviors were studied by combing electrochemical impedance spectroscopy (EIS) and equivalent circuit model. The results indicate that the higher the dosage, the better the conductivity, the percolation thresholds of CF and NCB are 0.05 vol% and 15 vol%. Curing age, moisture content and temperature have important effects on the conductivity, but the effects are restricted by the dosage of conductive fillers. The more the dosage of the CF, the smaller the effect, while the NCB has little limited effect. CF and NCB also have important effects on the mechanical properties and the CF-EGC and NCB-EGC still have high ductility. Finally, an equivalent circuit model is proposed which can well characterize the conductive behaviors under different conditions. [ABSTRACT FROM AUTHOR]

• Online OC and BC were measured by a newly developed TCA08 coupled with an AE33. • The annual average f biomass to BC was 27.1% but in winter it increased to 41.6%. • BrC contribute 30.8% to total absorption coefficient with winter maximum of 44.2%. • High AAE 370-520 and MAC BrC , 370 in winter suggest more impact from biomass burning. To elucidate the variations in mass concentrations of organic carbon (OC) and black carbon (BC) in PM 2.5 and their light absorption characteristics in Lanzhou, we conducted one-year online measurements by using a newly developed total carbon analyzer (TCA08) coupled with an aethalometer (AE33) from July 2018 to July 2019. The mean OC and BC concentrations were 6.4 ± 4.4 and 2.0 ± 1.3 µg/m3, respectively. Clear seasonal variations were observed for both components, with winter having the highest concentrations, followed by autumn, spring, and summer. The diurnal variations of OC and BC concentrations were similar throughout the year, with daily two peaks occurring in the morning and evening, respectively. A relatively low OC/BC ratio (3.3 ± 1.2, n = 345) were observed, indicating that fossil fuel combustion was the primary source of the carbonaceous components. This is further substantiated by relatively low biomass burning contribution (f biomass : 27.1% ± 11.3%) to BC using aethalometer based measurement though f biomass value which increased significantly in winter (41.6% ± 5.7%). We estimated a considerable brown carbon (BrC) contribution to the total absorption coefficient (b abs) at 370 nm (yearly average of 30.8% ± 11.1%), with a winter maximum of 44.2% ± 4.1% and a summer minimum of 19.2% ± 4.2%. Calculation of the wavelength dependence of total b abs revealed an annual mean AAE 370-520 value of 4.2 ± 0.5, with slightly higher values in spring and winter. The mass absorption cross-section of BrC also exhibited higher values in winter, with an annual mean of 5.4 ± 1.9 m2/g, reflecting the impact of emissions from increased biomass burning on BrC concentrations. [ABSTRACT FROM AUTHOR]

• First appearance and morphology research on 15 Asian lacquer coatings during aging. • Changes in transparency, color, gloss, surface roughness and waviness were found. • Impacts of drying oils, resins, pigments and iron treatment were revealed. • Different appearance and morphology changes over aging were compared. • Visual observation, photography, optical measurements and microscopy were optimized. Asian lacquer is one of the earliest natural polymers used in human history. Objects made with decorative Asian lacquer are among the most exquisite collections in museums. This is the first systematic study on the influence of historically used additives on the appearance and morphology changes of unaged and aged lacquer coatings. Macro and microanalytical methods were optimized to investigate the surface changes of lacquer caused by artificial aging. These included visual observation, visible photography, optical measurements (gloss, haze, blanching, macro-texture and color) and microscopy. Results showed that additives altered the transparency, color, and surface roughness and waviness of unaged lacquer surfaces. Aging caused changes in surface morphology, particularly an increase in roughness due to cracking and pitting, and waviness. The transparency of transparent coatings also increased with aging. The widest cracks and earliest formation of cracks with aging were observed for thitsi mixed with wood oil. High surface roughness was observed for aged lacquers treated with iron and for vermillion formulations. A significant reduction in gloss and an increase in blanching was observed for aged iron-treated lacquers due to extensive pitting and cracking. Formulations with vermillion exhibited the largest surface pits, which led to the largest reduction in gloss and the most blanching. Aging caused black spots and darkening of the vermillion pigment. Aged formulations with carbon black exhibited large pits on the surfaces. Analyses of the cracking showed that, to a large extent, the width, length and number of cracks were influenced by components in the formulations. The phenomena of crack closure and displacement were identified for the first time in lacquered objects. The causes of blanching are discussed and the extent of blanching was tentatively quantitatively expressed by gloss and haze data obtained by a goniophotometer. In general, changes in appearance and morphology occurred from the beginning of the light aging cycle, except for cracking. Preventive conservation strategies during exhibition and storage should be tailored according to the formulation and preservation conditions of specific lacquer coatings. This study contributes to the knowledge and conservation of Asian lacquered surfaces. The analytical protocols may also be of value for studying and documenting other coating formulations, and the surfaces of works of art. [Display omitted] [ABSTRACT FROM AUTHOR]

Hydrogen-based economy has a great potential for addressing the world's environmental concerns by using hydrogen as its future energy carrier. Hydrogen can be stored in gaseous, liquid and solid-state form, but among all solid-state hydrogen storage materials (metal hydrides) have the highest energy density. However, hydrogen accessibility is a challenging step in metal hydride-based materials. To improve the hydrogen storage kinetics, effects of functionalized catalysts/dopants on metal atoms have been extensively studied. The nanostructuring of metal hydrides is a new focus and has enhanced hydrogen storage properties by allowing higher surface area and thus reversibility, hydrogen storage density, faster and tunable kinetics, lower absorption and desorption temperatures, and durability. The effect of incorporating nanoparticles of carbon-based materials (graphene, C60, carbon nanotubes (CNTs), carbon black, and carbon aerogel) showed improved hydrogen storage characteristics of metal hydrides. In this critical review, the effects of various carbon-based materials, catalysts, and dopants are summarized in terms of hydrogen-storage capacity and kinetics. This review also highlights the effects of carbon nanomaterials on metal hydrides along with advanced synthesis routes, and analysis techniques to explore the effects of encapsulated metal hydrides and carbon particles. In addition, effects of carbon composites in polymeric composites for improved hydrogen storage properties in solid-state forms, and new characterization techniques are also discussed. As is known, the nanomaterials have extremely higher surface area (100–1000 time more surface area in m2/g) when compared to the bulk scale materials; thus, hydrogen absorption and desorption can be tuned in nanoscale structures for various industrial applications. The nanoscale tailoring of metal hydrides with carbon materials is a promising strategy for the next generation of solid-state hydrogen storage systems for different industries. [Display omitted] • The importance of tunability of Metal hydrides are discussed. • Summarized the effect of integrating carbon-based materials on Metal hydrides. • Presented synthesizing strategies for Metal hydrides and carbon-based materials. • Highlighted comparative summary of the characterization techniques. [ABSTRACT FROM AUTHOR]