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Transformer oil will inevitably be contaminated by impurity particles in the actual operation process; Carbon particles are the most abundant conductive particles in transformer oil. The adhesion behavior on the internal insulating surface will cause electric field distortion, which will pose a serious threat to the safe and stable operation of oil-immersed power equipment. To this end, this paper builds an experimental platform for simulating the adhesion behavior of carbon particles in transformer oil, studies the adhesion characteristics of carbon particles, and analyzes the influence of electric field, particle size, oil flow velocity, and other factors on the adhesion of carbon particles. The results show that: the DC electric field is the main factor driving the adhesion of carbon particles on the surface of epoxy resin (with the increase in electric field strength, the degree of adhesion of carbon particles firstly rises and then decreases); the smaller the size of the carbon particles, the easier it is to adhere, and the corresponding electric field strength is different for different sizes of carbon particles when the degree of adhesion is the largest; the velocity of the transformer oil will have a significant impact on the adhesion behavior of the carbon particles (with the increase in the flow velocity, the degree of adhesion of carbon particles firstly rises and then decreases). The research conclusion of this article is helpful in guiding the evaluation of insulation performance and the optimization of insulation structure design in the converter transformer valve-side bushing considering the phenomenon of particle adhesion. [ABSTRACT FROM AUTHOR]

Carbon particles, a primary component of diesel engine emissions, cause persistent erosion in the exhaust piping system, inevitably leading to performance degradation. This erosion can result in reduced fuel economy and increased emissions. The effects of three key parameters including solid particle size, turbine U/C operating conditions and rotational speed on the erosion characteristics of the flow channels of a radial turbine for vehicle diesel engine applications and their impact on performance were investigated through numerical simulations in the study. The findings indicate that larger particle size and higher rotational speed can significantly lead to the higher erosion rate density of the volute channel and casing wall surfaces. Reducing U/C does not substantially affect the distribution of erosion rate density. Centrifugal force will play an important role in the variation of erosion distribution characteristics. Compared to U/C, the other two key parameters are sensitive factors affecting turbine performance degradation. Under the same condition for operating 5000 h, 10 μm particles cause a 7.5-fold increase in efficiency loss change rate compared to 0.5 μm particles. The efficiency loss at 140 krpm is 16 times greater than that at 40 krpm. [ABSTRACT FROM AUTHOR]

Vegetable oils in the lubricant field are largely studied. Their efficiency depends on their viscosity parameters and their fatty acid composition. The actions of moringa oil used as a lubricant base and as a lubricant additive have been shown in this work. Graphite, carbon nanofibers, and carbon nanodots are carbon phases of different shapes used as solid additives. The tribological performances of lubricant blends composed of between 0.5 and 1 wt.% of particles have been evaluated using a ball-on-plane tribometer under an ambient atmosphere. No additional surfactant was used. The positive and important actions of a small amount of moringa oil added in the lubricant formulas are demonstrated. The results obtained allow us to point out the influence of the type and shape of particles. Physicochemical investigations allow us to propose a synergistic effect between the particles and moringa oil as additives in dodecane. [ABSTRACT FROM AUTHOR]

Green synthesis represents a superior strategy for mitigating the adverse effects of chemical synthesis on the environment. In particular, the utilization of bio-sourced materials for nanomaterial synthesis constitutes a more sustainable and environmentally sound alternative. In this study, silver–carbon particle (Ag-CP) nanocomposites were prepared by a green hydrothermal method using lily bulbs as raw materials and were employed for glucose detection. Through the use of various physical characterization techniques, it was demonstrated that the natural lily hydrothermal method yielded carbon particles that were modified with Ag nanoparticles. The electrochemical characteristics of the Ag-CP nanocomposites for glucose sensing were investigated using cyclic voltammetry and chronoamperometry. The results showed that the constructed glucose sensor was capable of detecting concentrations within the range of 1–11 mM (R2 = 0.998), with sensitivity of 203.56 μA mM−1 cm−2 and a detection limit of 76.6 μM (S/N = 3). The Ag-CP nanocomposite sensor also exhibited notable electrocatalytic activity and remarkable anti-interference capability. In light of the exceptional sensing performance, coupled with the straightforward and cost-effective preparation process, the development of nanocomposite materials employing naturally sourced biological materials represents an attractive avenue for the production of eco-friendly nanocomposites. [ABSTRACT FROM AUTHOR]

In the work, the regularities of high-temperature heat-mass exchange in two-fraction gas suspensions of carbon particles in heated air are studied. These studies are relevant for predicting high-temperature processes in combustion chambers and determining the main characteristics of these processes: induction period, time and temperature of combustion, critical parameters of ignition and extinction. Physico-mathematical modeling of the problem is carried out on the basis of the equations of heat and mass transfer and chemical kinetics for the components of the gas suspension, taking into account the molecular-convective and radiation mechanisms of heat transfer. The characteristics of ignition, burning, and extinction of a two-fraction gas suspension of carbon particles with equal mass concentrations of small (60 μm) and large (120 μm) fractions in the temperature range of 1100 ÷ 1500 K were studied; a comparison was made with the characteristics for single particles of the corresponding diameters. It has been proven that when the gas temperature decreases, the induction period of the fine fraction can exceed the induction period of the large fraction, while the combustion temperature of small particles becomes lower than the combustion temperature of large particles. At high gas temperatures (1400K, 1500K), the situation changes to the opposite. The critical ignition and extinction parameters of two-fraction gas suspensions (gas temperatures, particle diameters) were found.

Carbon dots are synthesized alone and in the presence of commercial magnetite nanoparticles using a simple hydrothermal reaction. The spectroscopic and structural characteristics of CDot and CDot–magnetite materials are presented and their behaviors under combustion conditions are studied. A careful examination of their combustion behaviors reveals interesting results for the CDot–magnetite material: it undergoes early catalytic combustion at ~200 °C and a strong endothermic process that quenches combustion. By investigating the physical mixtures of pre-formed CDots and magnetite and the starting material ascorbic acid and magnetite, it is determined that the strong endothermic behavior requires intimate interactions between the carbon source and the magnetite, highlighting the importance of the nano-interface of the CDots being synthesized onto the magnetite substrate. The results are discussed in the context of the fuels used for low-temper combustion, materials with stored endothermic potential, and the use of combustion-quenching materials for fire control. [ABSTRACT FROM AUTHOR]

Transformer oil will inevitably be contaminated by impurity particles in the actual operation process; Carbon particles are the most abundant conductive particles in transformer oil. The adhesion behavior on the internal insulating surface will cause electric field distortion, which will pose a serious threat to the safe and stable operation of oil-immersed power equipment. To this end, this paper builds an experimental platform for simulating the adhesion behavior of carbon particles in transformer oil, studies the adhesion characteristics of carbon particles, and analyzes the influence of electric field, particle size, oil flow velocity, and other factors on the adhesion of carbon particles. The results show that: the DC electric field is the main factor driving the adhesion of carbon particles on the surface of epoxy resin (with the increase in electric field strength, the degree of adhesion of carbon particles firstly rises and then decreases); the smaller the size of the carbon particles, the easier it is to adhere, and the corresponding electric field strength is different for different sizes of carbon particles when the degree of adhesion is the largest; the velocity of the transformer oil will have a significant impact on the adhesion behavior of the carbon particles (with the increase in the flow velocity, the degree of adhesion of carbon particles firstly rises and then decreases). The research conclusion of this article is helpful in guiding the evaluation of insulation performance and the optimization of insulation structure design in the converter transformer valve-side bushing considering the phenomenon of particle adhesion.

In the work, the regularities of high-temperature heat-mass exchange in two-fraction gas suspensions of carbon particles in heated air are studied. These studies are relevant for predicting high-temperature processes in combustion chambers and determining the main characteristics of these processes: induction period, time and temperature of combustion, critical parameters of ignition and extinction. Physico-mathematical modeling of the problem is carried out on the basis of the equations of heat and mass transfer and chemical kinetics for the components of the gas suspension, taking into account the molecular-convective and radiation mechanisms of heat transfer. The characteristics of ignition, burning, and extinction of a two-fraction gas suspension of carbon particles with equal mass concentrations of small (60 μm) and large (120 μm) fractions in the temperature range of 1100 ÷ 1500 K were studied; a comparison was made with the characteristics for single particles of the corresponding diameters. It has been proven that when the gas temperature decreases, the induction period of the fine fraction can exceed the induction period of the large fraction, while the combustion temperature of small particles becomes lower than the combustion temperature of large particles. At high gas temperatures (1400 K, 1500 K), the situation changes to the opposite. The critical ignition and extinction parameters of two-fraction gas suspensions (gas temperatures, particle diameters) were found. [ABSTRACT FROM AUTHOR]

Vegetable oils in the lubricant field are largely studied. Their efficiency depends on their viscosity parameters and their fatty acid composition. The actions of moringa oil used as a lubricant base and as a lubricant additive have been shown in this work. Graphite, carbon nanofibers, and carbon nanodots are carbon phases of different shapes used as solid additives. The tribological performances of lubricant blends composed of between 0.5 and 1 wt.% of particles have been evaluated using a ball-on-plane tribometer under an ambient atmosphere. No additional surfactant was used. The positive and important actions of a small amount of moringa oil added in the lubricant formulas are demonstrated. The results obtained allow us to point out the influence of the type and shape of particles. Physicochemical investigations allow us to propose a synergistic effect between the particles and moringa oil as additives in dodecane.

Aerogels, one of the first materials that come to mind in relation to lightweight and solid materials, have gained a place in various applications due to their remarkable properties. In this study, silica aerogels were synthesized with a hydro(solvo)thermal-supported sol–gel synthesis procedure. In order to determine the optimum conditions for the synthesis of the silica aerogel, the effect of some parameters was investigated. Nano- and micro-sized particles such as SiO2 and carbon particles were embedded/doped into the silica aerogel to obtain interpenetrating network structures. Then, the -NH2 functional group was added to the structure by using APTES modification and protonation was achieved by HCl treatment. All these structures were successfully used as catalysts for the dehydrogenation of NaBH4 in methanol. When CP-APTES-HCl silica aerogel was used as catalyst, the activation energy, enthalpy and entropy values for NaBH4 methanolysis were calculated as 38.25 kJmol−1, 35.79 kJmol−1, and -156.11 J mol−1 K−1, respectively. The calculated hydrogen generation rate at 298 K was 1860 mL min−1 g−1. The CP-APTES-HCl silica aerogel catalyst was used 6 times in a row in the same medium. The results showed that 100% conversion was achieved with each use. Although there was a slight decrease in activity with repeated use, a value close to 70% was obtained for the 6th use. [ABSTRACT FROM AUTHOR]

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

The research undertaken aimed to develop an efficient Pt-based catalyst for polymer electrolyte membrane fuel cells (PEMFCs) by using a cost-effective and efficient physical method to deposit platinum nanoparticles (PtNPs) on carbon supports directly from the platinum target. The method developed avoids the chemical functionalization of the carbon substrate and the chemical synthesis of PtNPs during catalyst fabrication. Platinum was deposited on carbon particles at room temperature using a pulsed laser deposition (PLD) system equipped with an ArF excimer laser (λ = 193 nm). The uniform deposition of PtNPs on carbon supports was achieved thanks to a specially designed electromechanical system that mixed the carbon support particles during platinum deposition. In the studies, Vulcan XC-72R carbon black powder, a popular material used as support in the anodes and cathodes of PEMFCs, and a porous carbon material with a high degree of graphitization were used as carbon supports. The best electrochemical measurement results were obtained for Pt deposited on Vulcan XC-72R. The peak power density measured for this material in a membrane electrode assembly (MEA) of a PEMFC (fed with H2/Air) was 0.41 W/cm2, which is a good result compared to 0.57 W/cm2 obtained for commercial 20% Pt Vulcan XC-72R. This result was achieved with three times less Pt catalyst on the carbon support compared to the commercial catalyst, which means that a higher catalyst utilization factor was achieved.

The properties of polymer films obtained in plasma of barrier discharge at atmospheric pressure from aniline of amorphous form with simultaneous formation of carbon particles in the films were studied. The threshold of discharge energy density was established (~30 mJ/m), beginning from which a continuous film filled with agglomerates of carbon particles can be obtained. The structure of such films corresponds to the form typical of amorphous polymers. Carbon particles form agglomerates, the concentration of which weakly depends on the discharge energy density and constitutes ~(4–7) × 104 1/cm2, which does not allow increasing the conductivity. It was shown that the main contribution to the conductivity of films obtained from aniline and filled with carbon particles is made by the value of their moisture saturation. It was found that the creep of the material decreases with growth of the energy density, and hardness increases. This is associated with the formation and growth of the number of crosslinks in the samples with an increase in the energy input. The absolute values of Martens hardness correspond to the lower boundary for polyaniline, which is due to the small molecular weight of the obtained polymer. [ABSTRACT FROM AUTHOR]

Carbon dots are synthesized alone and in the presence of commercial magnetite nanoparticles using a simple hydrothermal reaction. The spectroscopic and structural characteristics of CDot and CDot–magnetite materials are presented and their behaviors under combustion conditions are studied. A careful examination of their combustion behaviors reveals interesting results for the CDot–magnetite material: it undergoes early catalytic combustion at ~200 °C and a strong endothermic process that quenches combustion. By investigating the physical mixtures of pre-formed CDots and magnetite and the starting material ascorbic acid and magnetite, it is determined that the strong endothermic behavior requires intimate interactions between the carbon source and the magnetite, highlighting the importance of the nano-interface of the CDots being synthesized onto the magnetite substrate. The results are discussed in the context of the fuels used for low-temper combustion, materials with stored endothermic potential, and the use of combustion-quenching materials for fire control.

The article deals with a boundary value problem of mathematical physics describing the unsteady process of diffusion of a reacting gas in the direction of a spherical coal particle located in the atmosphere of a mine. The solution of the boundary value problem is based on self-similar transformations which are a special case of group analysis. Formulas for determining the concentration of the reacting gas in the vicinity of the coal particle and on its surface are obtained. Graphs of the dependencies of the burn-out time of the coal particle on a number of its parameters are constructed, and the fields of the reacting gas concentration at various stages of burning of the coal particle are revealed. [ABSTRACT FROM AUTHOR]

A large amount of contaminants are collected on the cardboard surface of the valve-side bushing outlet of a converter transformer that has been operating for a long period, and can cause the performance of the oil–paper insulation to degrade. The analysis of their energy spectrum has shown that these contaminants contain free carbon. To investigate causes of the formation of these carbon traces, the authors of this study analyze their law of growth on the surface of the insulating paper in the presence of pure insulating oil and insulating oil containing carbon particles. We examined the influence of carbon tracks of different lengths on the breakdown voltage along the surface of the oil–paper insulation. The results showed that carbonization on the surface of the insulating paper generated carbon traces in pure insulating oil and eventually led to the formation of conductive channels. Moreover, carbon traces were generated by carbon particles deposited on the surface of the insulating paper in insulating oil containing carbon particles. The carbon traces grew from the high-voltage electrode to the ground electrode along the direction of the electric field in both types of oils. The formation of the conductive channel through the poles of the paper in insulating oil containing carbon particles required a lower voltage and a shorter discharge time than that in pure insulating oil. As the concentration of the carbon particles increased, the rate of growth of carbon traces on the surface of the insulating paper increased such that the oil–paper insulation failed earlier than otherwise. Long carbon traces were formed on the surface of the insulating paper in case of a high concentration of carbon particles under the DC pre-pressure mode, and this led to a reduction in the breakdown voltage along the surface of the oil–paper insulation.

Oxidative cleavage of unsaturated fatty acids involves the rupture of carbon‐carbon double bonds to produce carbonyl compounds of high added value. This reaction is mainly performed using homogenous catalysts which are pollutant and cannot be recovered while current heterogeneous catalysts display poor activity. To solve this issue, an active catalyst was prepared by impregnating Ru ions on carbon spheres synthesized by hydrothermal carbonization of a glucose solution. Carbon spheres were calcined under air atmosphere to create porosity and functionalized with polydopamine to improve their ability to complex Ru ions. The catalyst was fully characterized and completed the oxidative cleavage of oleic acid within 7 h of stirring at room temperature using NaIO4 as oxidizing agent. The addition of N‐methylmorpholine N‐oxide, a green oxidizing agent, allowed >99 % conversion in only 5 h. Therefore, it was possible to conceive an eco‐friendly carbon catalyst for the valorization of oleic acid under mild conditions. [ABSTRACT FROM AUTHOR]

Simple Summary: Gastric cancer is a major health risk, and surgery is the primary curative option. However, the appropriate extent of lymph node dissection and appropriate surgical margins are two major issues that need to be addressed. Clinical tracers are an excellent solution. Therefore, we compiled a list of common clinical tracers for gastric cancer surgery to help surgeons better select and use them. The treatment of gastric cancer mainly depends on radical gastrectomy. Determination of appropriate surgical margins and adequate lymph node (LN) resection are two major surgical steps that directly correlate with prognosis in gastric cancer. Due to the expanding use of minimally invasive procedures, it is no longer possible to locate tumors and LNs through touch. As an alternative, tracers have begun to enter the field due to their capacities for intraoperative visualization. Herein, we summarize the application of contemporary tracers in gastric cancer surgery, including isosulfan blue, methylene blue, patent blue, indocyanine green, carbon particles, and radioactive tracers. Their mechanisms, administration methods, detection efficiency, and challenges, as well as perspectives on them, are also outlined. [ABSTRACT FROM AUTHOR]

The addition of fine carbon particles to working fluids of water–oil emulsion type is considered as a means of decreasing the final surface roughness in cutting. The effect of reducing the size of the oil droplets is also investigated. The interaction of the fine components within the working fluid is studied. [ABSTRACT FROM AUTHOR]

Carbonaceous nanoparticles prepared via solvothermal treatment of citric acid with urea or thiourea have revealed selective response to mercury(II) ions enabling their quantitative determination by means of fluorescence spectroscopy. Dialysis of carbonaceous particles has improved their sensing capacity (reducing the detection limit and extending the detection range). Size distribution of the carbonaceous particles has been directly measured by means of nanoparticles tracking analysis for the first time. [ABSTRACT FROM AUTHOR]

Electrochemical hydrogen storage in porous carbon particles in slurry electrodes is a function of particle size, shape, and material. Ideal slurry electrodes have high electrical (both electronic and proton) conductivity to minimise the electric resistance and ohmic power loss, and low viscosity to minimise parasitic pumping power, while utilising porous particles with high surface areas for hydrogen storage. In this paper we show that although carbon black (CB) particles have higher electronic conductivity than activated carbon (aC) particles, their proton conductivity is significantly lower, and they cannot be used for hydrogen storage. We increase the electronic conductivity of aC slurries by adding CB particles. We demonstrate that the addition of a 1:10 ratio by weight of CB to aC particles reduces the electric resistance and ohmic power loss by 50%, while parasitic pumping power increases by only 15% compared to slurries with no CB particles. We conclude that at low Reynolds numbers, for 5 to 20 wt% aC slurries with different particle sizes, slurries containing 20 wt% spherical aC particles smaller than 50 μm mixed with 2 wt% CB particles provide the highest electronic and proton conductivity, while not significantly increasing parasitic pumping power. • Particle characteristics affect slurries electrochemically and rheologically. • Optimising slurries concentration maximises the efficiency of hydrogen storage system. • Adding CB particles increases the electrical conductivity of aC slurries. • Porous particles only contributed to the proton exchange process. • A balance between electric resistance and pumping power of slurries is required. [ABSTRACT FROM AUTHOR]

Conventional conductive homopolymers such as polypyrrole and poly-3,4-ethylenedioxythiophene (PEDOT) have poor mechanical properties, for the solution to this problem, we tried to construct hybrid composites with higher electrical properties coupled with high mechanical strength. For this purpose, Kevlar fibrous waste, conductive carbon particles, and epoxy were used to make the conductive composites. Kevlar waste was used to accomplish the need for economics and to enhance the mechanical properties. At first, Kevlar fibrous waste was converted into a nonwoven web and subjected to different pretreatments (chemical, plasma) to enhance the bonding between fiber-matrix interfaces. Similarly, conductive carbon particles were converted into nanofillers by the action of ball milling to make them homogeneous in size and structure. The size and morphological structures of ball-milled particles were analyzed by Malvern zetasizer and scanning electron microscopy. In the second phase of the study, the conductive paste was made by adding the different concentrations of ball-milled carbon particles into green epoxy. Subsequently, composite samples were fabricated via a combination of prepared conductive pastes and a pretreated Kevlar fibers web. The influence of different concentrations of carbon particles into green epoxy resin for electrical conductivity was studied. Additionally, the electrical conductivity and electromagnetic shielding ability of conductive composites were analyzed. The waveguide method at high frequency (i.e., at 2.45 GHz) was used to investigate the EMI shielding. Furthermore, the joule heating response was studied by measuring the change in temperature at the surface of the conductive composite samples, while applying a different range of voltages. The maximum temperature of 55 °C was observed when the applied voltage was 10 V. Moreover, to estimate the durability and activity in service the ageing performance (mechanical strength and moisture regain) of developed composite samples were also analyzed. [ABSTRACT FROM AUTHOR]

A novel electrostatic precipitator was developed for collecting and decomposing soot in exhaust gas from combustion devices, including diesel engines. In the precipitator, the dielectric surface works as a collection electrode.As one of the key processes in this technique is charging the dielectric surface, the surface potential distributions were first investigated using glass plates as the dielectric surfaces with a positively biased ac voltage applied to discharge electrodes placed on the glass plate. Results showed that positive ions created by the breakdown of air charged the surface, and the associated intermittent voltage was sufficient for building the surface potential. The area of PM adhesion was then investigated experimentally using real exhaust gas and numerically by simulating the trajectories of the charged particles. The results showed that the uneven surface potential was the essential factor involved in the collection of particles and that the unevenness was due to the intermittent voltage applied to the glass surface. Creating and utilizing the potential unevenness along the dielectric surface for particle collection made this system unique among ESPs (electrostatic precipitator) that have been researched. [ABSTRACT FROM AUTHOR]

Over the recent years, carbon particles have gained relevance in the field of biomedical application to diminish the level of endo-/exogenous intoxication and oxidative stress products, which occur at different pathological states. However, it is very important that such carbon particles, specially developed for parenteral administration or per oral usage, possess a high adsorption potential and can remove hazard toxic substances of the hydrophilic, hydrophobic and amphiphilic nature usually accumulated in the blood due to the disease, and be absolutely safe for normal living cells and tissues of organism. In this work, the stable monodisperse suspension containing very small-sized (Dhydro = 1125.3 ± 243.8 nm) and highly pure carbon particles with an excellent accepting ability were obtained. UV-spectra, fluorescence quenching constant and binding association constant were provided by the information about conformational alterations in an albumin molecule in presence of carbon particles, about the dynamic type of quenching process and low binding affinity between carbon and protein. The later was confirmed by DSC method. In vitro cell culture experiments showed that carbon particles did not possess any cytotoxic effect towards all testing the normal cell lines of different histogenesis, did not show genotoxic effects and were absolutely safe for experimental animals during and after their parenteral administration. These observations may provide more information about how to develop a safe preparation of carbon particles for different biomedical applications, in particular, as a mean for intracorporeal therapy of various heavy diseases accompanied by the increased endogenous intoxication and the level of oxidative stress.

The hypothesis of microscopic hot spots is widely used to explain the unique microwave (MW) effect in materials science and chemical engineering, but it has not yet been directly measured. Herein we use Eu/Tb mixed‐metal organic complexes as nano thermometers to probe the intrinsic temperature of MW‐absorbing particles in MW fields based on the thermosensitive fluorescent spectra. According to the measurements of the temperature gradient at the solid/liquid interphase, we derive an MW‐irradiated energy transfer model to predict the extent of microscopic hot spots. The fluorescence results agree with the model predictions that the MW‐induced temperature gradient can be enlarged by increasing MW intensity, as well as the dielectric loss and size of particles. Conversely, the increase in the thermal conductivity and the dielectric loss of the liquid lowers the temperature gradient. This study enables control of MW‐assisted synthesis and MW‐responsive techniques. [ABSTRACT FROM AUTHOR]

Fiber-forming polymer composites filled with carbon nanoparticles of three types (carbon black is a spherical filler; carbon nanofibers and carbon nanotubes are anisotropic nanoparticles) were produced by melt technology. Electrical conductivity of the fiber-forming polymer composites was measured; a function of the filler concentration and the percolation thresholds were determined. It was found that an increase in the aspect ratio of carbon nanoparticles leads to a decrease in the percolation threshold. The correlation between the axial ratio, stiffness, filler concentration and electrical conductivity of the percolation cluster in fiber-forming polymer composites was analysed.

Zein-based materials were produced by dissolving zein water at pH 13, and subsequently congealing it with CaCl2. Biocarbon particles were produced with miscanthus biomass by pyrolization at 650 °C (M-L) and at 900 °C (M-H), followed by ball-milling. Increasing the pyrolization temperature caused the disappearance of functional groups on the particle surface and increased their hydrophobicity of the particles (as shown through Attenuated Total Reflection- Fourier Transform Infrared Spectroscopy, ATR-FTIR and by the preferential partitioning on the particles in toluene rather than water). Therefore, hydrophobic interactions were likely stronger between zein and M-H particles, than between zein and M-L particles. Measurements conducted using a zeta sizer showed that aggregates of zein and M-L particles were > 1 µm, and aggregates of zein and M-H particles were < 1 µm. M-H particles increased the shear viscous (G″) and elastic (G″) moduli of zein, and rendered the material elastic (G′ ≅ 6.6 × 104 Pa > G″ ≅ 5.7 × 104 Pa with M-H and G′ ≅ 4.3 × 104 Pa and G″ ≅ 4.6 × 104 Pa without zein). M-H particles also increased the tensile strength of zein materials, potentially improving their usefulness as bioplastics. M-L particles increased the viscoelastic moduli of zein (G′ ≅ 6.7 × 104 Pa and G″ ≅ 7.3 × 104 Pa), but did not render the material elastic (i.e. G′ was not greater than G″). Moreover, M-L particles stiffened zein at small elongational deformations, but rendered it brittle at larger deformations. M-H particles greatly reduced the permeability of zein barriers injected in sandy media, which can be for instance used to prevent the migration of subsurface contaminants. Flow reduction was 90% with zein and M-H, whereas it was 64% with zein only and 68% with zein and M-L particles and zein. [ABSTRACT FROM AUTHOR]

Biofuel cells are an attractive alternative to conventional fuel cells, because they use biological catalysts. We report in this article the construction of an ethanol/O2 enzymatic biofuel cell. In the first time, the performance comparison with different methods for ethanol/O2 biofuel cell has been study. Alcohol dehydrogenase, a nicotinamide adenine dinucleotide (NAD)-dependent enzyme, is immobilized with NAD+, diaphorase, and vitamin K3 (VK3) on the electrode. The oxygen is reduced at the cathode with laccase and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonate) (ABTS). The performances of the electrodes are improved thanks to addition of carbon powder (KS6 and Super P® carbon). The benefit of the carbon particles with higher surface porosity was explained by the high-porous structure that offered a closer proximity to the reactive species and improved diffusion of ethanol and oxygen within the enzyme films. Efficiency of immobilization of NAD+ cofactor has been also demonstrated. We have shown the effect of multi-enzymatic reaction at the anode on the storage and operational stability. A high open-circuit potential has been recorded 1.02 V, demonstrating the benefit of NAD+ immobilization with maximal power density of 300 μW cm−2. Chronoamperometric measurements show a current density of 90 μA cm−2 during 20 h demonstrating the operational stability of the ethanol biofuel cell based on NAD+ cofactor immobilization. [ABSTRACT FROM AUTHOR]

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

The current study was focused on the development of electrically conductive composites of carbon particle filled cotton fabric/epoxy systems. The carbon particles were refined to the scale of micro/nanoparticles using ball milling and morphological properties were studied by Malvern zetasizer and SEM. The influence of different concentrations of carbon particles in green epoxy resin for electrical conductivity was studied. Additionally, the electrical conductivity and electromagnetic shielding ability of conductive composites were analyzed. Waveguide method at high frequency (i.e. at 2.45 GHz) was used to investigate the EMI shielding. Similarly, the effect of different concentrations of carbon particles in composites was also studied for mechanical strength (tensile and flexural). A comprehensive study showed the improvements in electrical and mechanical properties with increase in the concentration of carbon particles and their even distribution in resin. The composites with higher carbon filler concentration showed maximum electrical conductivity (1.0E–02), shielding effectiveness 23.13 dB and mechanical properties. [ABSTRACT FROM AUTHOR]

We investigate the conductivity of a composite of PANI-PAMPSA and PANI-PAMPSA with carbon particles by impedance spectroscopy. We establish that the addition of carbon particles to the PANI-PAMPSA composite leads to a significant rise in the conductivity over the entire range of frequencies studied (from 10 Hz to 5 MHz). Such increase in conductivity is very important for using the PANI-PAMPSA composite in solar energy. We propose an equivalent electrical circuit of the samples investigated. At low frequencies, the conductivity dependence on frequency indicates the hopping mechanism of the charge carrier transport. [ABSTRACT FROM AUTHOR]

Some fundamental aspects of the aerosol-assisted chemical vapor deposition of carbon-containing nanoparticles from an aerosol of ortho-xylene are described, including the influence exerted by the pyrolysis temperature and flow rate of the carrier-gas on the size characteristics, structure, and composition of the products being formed. It was shown that the shape, size, and structure of particles are determined by processes occurring in the pyrolysis zone, and its temperature is the most important technological parameter, together with the residence time in the reaction zone of products formed in the decomposition of ortho-xylene. The results obtained are of practical importance and form a basis for development of technology and equipment for producing carboncontaining nanoparticles from an aerosol of ortho-xylene. [ABSTRACT FROM AUTHOR]

Bone regeneration for replacing and repairing damaged and defective bones in the human body has attracted much attention over the last decade. In this research, highly porous polyetheretherketone (PEEK)/hydroxyapatite (HA) bionanocomposite scaffolds reinforced with carbon fiber (CF) and carbon nanotubes (CNTs) were fabricated, and their structural, mechanical, and biological properties were studied in detail. Salt porogen (200–500 µm size) leaching methods were adapted to produce porous PEEK structures with controlled pore size and distribution, facilitating greater cellular infiltration and biological integration of PEEK composites within patient tissue. In biological tests, nanocomposites proved to be non-toxic and have very good cell viability. In addition, bone marrow cell growth was observed, and PEEK/HA biocomposites with carbon particles showed increased cell attachment over the neat PEEK/HA composites. In cell viability tests, bionanocomposites with 0.5 wt% CNTs established good attachment of cells on disks compared to neat PEEK/HA biocomposites. A similar performance was seen in culture tests of bone marrow cells (osteoblasts and osteoclasts). The 0.5 wt% CF for osteoblasts and 1 wt% CNTs for osteoclasts showed higher cell attachment. The addition of carbon-based nanomaterials into PEEK/HA has been identified as an effective approach to improve cell attachment as well as mechanical and biological properties. With confirmed cell attachment and sustained viability and proliferation of the fabricated PEEK/HA/CNTs, CF bionanocomposites were confirmed to possess excellent biocompatibility and will have potential uses in bone scaffolding and other biomedical applications.

Carbon microparticles were produced from different technical lignins, i.e., kraft lignin, soda lignin, lignosulfonate, and organosolv lignin, at different carbonisation temperatures (800 °C, 1200 °C, 1600 °C, and 2000 °C). Before carbonisation, oxidative thermostabilization was performed. The combination of thermostabilization and carbonisation led to a high mass loss and shrinkage, but no major effect on the particle morphology was apparent. The carbon particles obtained from all four lignin variants developed disordered graphitic structures at high carbonisation temperatures, and good electrical conductivities in the carbon powders were observed for all lignin variants, with the exception of lignosulfonate. The polycaprolactone composite films filled with 30% lignin-derived carbon exhibited various conductivities, with the best results achieved using the kraft lignin-derived carbon. [ABSTRACT FROM AUTHOR]

The influence of the nature of stabilizing amphiphilic additives on the dispersion and precipitation of carbon nanoparticles was evaluated. The stabilized systems were tested for adsorption properties with respect to spectral probes and drugs for which purpose the degree of removal and the amount adsorbed were determined spectrophotometrically for dye Orange OT and anti-inflammatory drug indomethacin. [ABSTRACT FROM AUTHOR]

The aim of the presented research was to study the influence of surface layer material on improvement of impact, dielectric, EMI shielding and sound absorption properties of sandwich composites. The sandwich composite structure consisted of Kevlar or Carbon woven fabric at the surface layer, recycled high loft nonwoven in the center and a mixture of carbon particles/epoxy matrix as a binder to hold the surface layer and core together. The carbon particles were incorporated in epoxy in order to improve failure mechanism and enhance dielectric properties or electromagnetic shielding of sandwich composites. The biggest improvements on impact properties of sandwich composites were obtained when Kevlar fabric was used as surface layer. However, surface layer of carbon fabric was found to provide better dielectric properties and improve EMI shielding of sandwich composites against Kevlar fabric surface layer. [ABSTRACT FROM AUTHOR]

The effect of sodium dodecyl sulfate and carbon particles/nanotubes on the electropolymerization of aniline from oxalic acid solution onto a graphite electrode was investigated. The morphology and chemical structure of the as-synthesized polyaniline films were studied by means of SEM, XPS, NEXAFS, FTIR, and Raman spectroscopy. The electrochemical characteristics of the films were also analyzed in sulfuric acid solution. It has been shown that in the presence of sodium dodecyl sulfate, the polymerization rate increases significantly. In the synthesized polyaniline films, all imine groups and most of amine groups are protonated, with dodecyl sulfate ions being intercalated in the polymer. In the presence of sodium dodecyl sulfate, plate-like polyaniline forms large agglomerates with an extended surface and high electrochemical activity. It has been shown that the electrodeposition carried out in the presence of sodium dodecyl sulfate and suspended activated graphite particles or carbon nanotubes favors the formation of composite coatings with high specific capacitance. [ABSTRACT FROM AUTHOR]

Solid fuel particles will become increasingly important in the future. Present energy conversion systems for solid fuels are too inefficient. New energy conversion systems for solid fuels with higher energy conversion efficiencies are possible. Fuel cell technology is a key-technology in these new conversion systems. The direct carbon fuel cell (DCFC) operates on carbon particles obtained from a variety of solid fuel feedstocks. The DCFC is the only fuel cell designed to directly oxidize carbon particles in a special anode chamber. The particles are generally graphite structure with high purity. The electrolyte used is the high temperature solid oxide, molten carbonate or hydroxide electrolyte. Since a pure stream of CO2 is produced the stream can easily be sequestered and disposed. Pure carbon dioxide produced as a by-product would also have a market in many industries. A well defined technology roadmap identifying key research and development (R&D) issues is necessary to provide a framework for the development of these systems and to prevent entrenchment in inherently inefficient technologies. This review paper describes the direct carbon fuel cell and its system, how it works, the developmental status, the characteristics of the carbon particles needed, and the research and development issues for the technology.

The inability of ceramic and nanoceramic processing without expensive diamond tools and with a high-material-removal rate hampers the scope of its potential applications and does not allow humanity to make a full shift to the sixth technological paradigm associated with Kuhn scientific revolutions and Kondratieff’s waves and restrains the growth of the economy. The authors completed a review on the research state of ceramic and nanoceramic processing by electrical discharge machining, which is possibly solved by two principal approaches associated with the usage of standard commercially available machine tools. The first approach is related to the introduction of expensive secondary phase; the second approach proposes initiate processing by adding auxiliary electrodes in the form of coating, suspension, aerosol, or 3D-printed layer based on the components of silver, copper, or graphite in combination with an improved dielectric oil environment by introducing graphite or carbon nanoparticles, which is hugely relevant today.

Gasification of biomass gives off syngas that is contaminated mostly by carbon particulates and tars. The degree of contamination is attributed to factors such as gasification process, type of gasifier and type of biomass material. Downdraft gasifier minimizes the production of tar to a tolerable limit for engine applications; however, carbon particles still pose a challenge particularly with the integration of a heat exchanger for the purpose of heat recovery from the product gas. The presence of carbon particles in the syngas does influence the heat recovery process and materials used in the recovery. Hence, there is need for the characterization of these carbon particles to ascertain their chemical compositions, thermal properties and morphological features. This study was aimed at evaluating the characteristic features of carbon particles recovered from the syngas stream during gas cleaning at the cyclone. The elemental analysis of the carbon particle samples was performed using energy dispersive X-ray spectroscopy. An electron beam from scanning electron microscopy was passed through the sample surface at a magnification of 1000x and an accelerating voltage of 15 kV to determine the morphological features of the carbon particles. Their thermal properties were investigated using a thermogravimetric analyzer at a heating rate of 10°C/min. A weight loss of approximately 5.4 wt % was recorded at the maximum temperature of 900 °C. Silicon, oxygen and carbon were found to be the dominating elements in the carbon particulate. [ABSTRACT FROM AUTHOR]

A Proton flow reactor (PFR) system stores energy in the form of hydrogen in porous carbon particles in slurry electrodes. However, the hydrogen storage mechanisms and the reactions in this system are not well understood. In this study, we design and fabricate a microfluidic proton flow reactor (MPFR) as a small-scale PFR to enable in-situ visualisation of the key processes underlying PFR operations. We observe the behaviour of slurries and water in both hydrogen and oxygen sides with emphasis on processes in the vicinity of membranes. We use fluorescence microscopy with quinine to visualize hydronium transport from the oxygen to the hydrogen side and employ in-situ Raman spectroscopy to analyze surface structural changes in carbon particles before and after charging. Fluorescence microscopy demonstrates the formation of hydronium ions on the oxygen side and their subsequent migration to the hydrogen side, proving that the oxygen evolution reaction occurs on the oxygen side. Raman heat maps prove the formation of carbon–hydrogen bonding in particles after they are charged with PFR. Although the MPFR is operated at non-optimal slurry concentrations to allow optical access, we demonstrate that it provides maximum hydrogen storage capacity of 0.64 wt%. • Hydrogen storage in carbon slurries is shown using a proton flow reactor (PFR). • Key processes in hydrogen storage were observed in a microfluidic PFR. • Hydronium ions were detected in the electrolyte using fluorescence microscopy. • Hydrogen was identified on the particles after charging using Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Carbon-bound exogenous compounds, such as polycyclic aromatic hydrocarbons (PAHs), tobacco-specific nitrosamines, aromatic amines, and organohalogens, are known to affect both tumor characteristics and patient outcomes in lung squamous cell carcinoma (LUSC); however, the roles of these compounds in lung adenocarcinoma (LUAD) remain unclear. We analyzed 11 carbon-bound exogenous compounds in LUAD and LUSC samples using in situ high mass-resolution matrix-assisted laser desorption/ionization Fourier-transform ion cyclotron resonance mass spectrometry imaging and performed a cluster analysis to compare the patterns of carbon-bound exogenous compounds between these two lung cancer subtypes. Correlation analyses were conducted to investigate associations among exogenous compounds, endogenous metabolites, and clinical data, including patient survival outcomes and smoking behaviors. Additionally, we examined differences in exogenous compound patterns between normal and tumor tissues. Our analyses revealed that PAHs, aromatic amines, and organohalogens were more abundant in LUAD than in LUSC, whereas the tobacco-specific nitrosamine nicotine-derived nitrosamine ketone was more abundant in LUSC. Patients with LUAD and LUSC could be separated according to carbon-bound exogenous compound patterns detected in the tumor compartment. The same compounds had differential impacts on patient outcomes, depending on the cancer subtype. Correlation and network analyses indicated substantial differences between LUAD and LUSC metabolomes, associated with substantial differences in the patterns of the carbon-bound exogenous compounds. These data suggest that the contributions of these carcinogenic compounds to cancer biology may differ according to the cancer subtypes.