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A facile and sensitive electrochemical sensor for determining imatinib (IMA) was constructed by modifying a glassy carbon electrode (GCE) with a nanocarbon material, acetylene black (AB). The electrochemical behavior of IMA on the prepared GCE/AB was studied using electrochemical techniques, namely, differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy. The direct determination of IMA by the GCE/AB sensor was accomplished using DPV under optimized conditions. The method verification showed that the oxidation peak current was proportional to the concentrations of IMA in the linear ranges of 0.01–0.5 and 0.5–4 μM, with correlation coefficients of 0.9856 and 0.9946, respectively. The limit of detection of the GCE/AB sensor was 0.15 nM. Moreover, the GCE/AB sensor showed good precision and accuracy. Finally, the GCE/AB sensor was successfully applied to determine IMA in human serum samples, and the recoveries were satisfactory. [ABSTRACT FROM AUTHOR]

With the increasing role of hydrogen in the global market, new ways of hydrogen production are being sought and investigated. One of the possible solutions might be the plasma pyrolysis of methane. This approach provides not only the desired hydrogen, but also valuable carbon-containing products, e.g., carbon black of C2 compounds. This review gathers information from the last 20 years on different reactors that were investigated in the context of methane pyrolysis, emphasizing the different products that can be obtained through this process. [ABSTRACT FROM AUTHOR]

The porous structure of acetylene black was studied depending on the conditions of its preparation in the decomposition of acetylene: at various pressures in a tubular reactor of limited volume, decomposition of acetylene in mixtures with CH4, H2, or Ar and decomposition of acetylene in the presence of acetylene black and in reactors of various shapes. It has been found that the decomposition of pure acetylene with an increase in pressure from 2.35 to 5 bar increases the surface area of acetylene black from 75 to 125 m2/g, and the average particle size decreases from 36 to 22 nm. Additives of CH4, H2 or Ar inhibit the decomposition of acetylene, while the degree of inhibition decreases in the following sequence: H2 > CH4 > Ar. Relatively small additions of hydrogen block the decomposition of acetylene, practically without affecting the size of acetylene black particles. On the contrary, addition of methane leads to a significant increase in the average size of acetylene black particles to 55 nm and a corresponding decrease in the specific surface area to 57 m2/g. Addition of argon to acetylene qualitatively affects the porous structure of acetylene black in the same way as reducing the pressure of acetylene. During the decomposition of acetylene in the presence of acetylene black remaining in the reactor after the previous decomposition, a nonmonotonic change in the specific surface area and size of acetylene black particles was observed. It was shown in experiments with reactors different in shape but identical in volume that, with a decrease in the linear dimensions of the reaction vessel (length/diameter ratio), the surface area of the formed acetylene black increases rather significantly, and the average size of acetylene black particles decreases. [ABSTRACT FROM AUTHOR]

In order to reduce greenhouse gas emissions and ensure the transition to hydrogen economy, the development of new carbon-neutral technologies is required. One of the possible technologies is the detonation decomposition of acetylene with the simultaneous production of hydrogen and carbon black with a minimal emission of carbon monoxide. Acetylene for this purpose can be obtained by various methods, including plasma conversion of methane without CO 2 emission. This paper presents the results of experiments on the production of hydrogen and carbon black in the form of Nanoscale Detonation Carbon (NDC) on a laboratory version of the Pulse Gas-Detonation Device. This apparatus can produce 1.7 kg of hydrogen and 17.7 kg of NDC per hour. • Acetylene as an intermediate product between methane and hydrogen. • Detonation of fuel-rich acetylene-oxygen mixtures. • Detonation excitation at atmospheric pressure. • Hydrogen obtained together with carbon black. • Carbon footprint reduction. [ABSTRACT FROM AUTHOR]

Acetylene black is a special type of carbon black, obtained from the thermal decomposition of acetylene. Acetylene flames enable the investigation of the soot optical properties. A reliable knowledge of the optical properties of acetylene soot is necessary for interpreting the optical measurements in flames and the development of acetylene black applications in industry. However, a wide variation in the optical properties of soot is observed in different formation conditions. The main factors affecting soot formation in flames are fuel composition, equivalence ratio, and reaction time connected with the height above a burner. In this study, we measured the absolute value of the refractive index function of acetylene soot E(m,1064) at a wavelength of 1064 nm, as well as the ratio of the refractive index functions E(m,1064)/E(m,532) at laser wavelengths of 532 nm and 1064 nm in a premixed acetylene/air flame using laser-induced incandescence. The soot structure was studied using high-resolution electron microscopy. The obtained results showed that E(m,1064) increased from 0.19 to 0.53 and that the ratio of E(m,1064)/E(m,532) increased from 1.12 to 1.55 according to the height above a burner. These changes in the optical properties are attributed to differences in soot structure, such as different distances between graphene planes inside soot crystallites, which decreased from 0.43 to 0.36 nm as the height above the burner increased from 5 to 20 mm. It was concluded that the optical properties and structure of acetylene soot differ from those formed in other hydrocarbon flames. [ABSTRACT FROM AUTHOR]

In order to solve the problem of toxic and harmful gas and carbon black dust escaping during the separation of carbon black water in the production of acetylene from natural gas, two flocculants, polyacrylamide (PAM) and basic aluminum chloride (BAC), were used to flocculate carbon black water. The results show that the combination of PAM and BAC can reduce the separation time of carbon black water. Under 81 °C , when the dosage of PAM is 0. 02 g/g carbon black, the dosage of BAC is 0. l g/g carbon black, carbon black water with the solid content of 0. 17 wt% can be separated in 20 s, the solid content of water phase is 0. 067 wt% , and the viscosity (22 °0 of water phase is l. Oo mPa • s. The effects of PAM dosage on the recycling of carbon black water are investigated and the technological process of closed separation of carbon black water with flocculants is put forward [ABSTRACT FROM AUTHOR]

It was noted a significant increase in soot formation with the addition of methane in the pyrolysis of acetylene in shock tubes. Qualitative kinetic analysis revealed an increase of propargyl formation due to methyl/methylene and acetylene recombination. Here, we study the role of methyl radicals in the soot formation process more carefully. Mixtures of acetylene with various sources of methyl radicals – methane, diacetyl and dimethyl ether (DME) – were studied under shock tube pyrolysis conditions over a temperature range of 1650–2250 K and a pressure range of 3.5–4.5 bar. Laser light extinction was used for soot volume fraction and induction time of the particle inception measurements. A more than threefold increase in soot volume fraction with the addition of 1% of methane and 2% of acetylene diluted in argon was observed. Additions of diacetyl and DME resulted in less significant increases in soot volume fraction. All additions of methane, diacetyl and DME reduced the induction time of particle inception. The numerical modeling of the initial gas phase part of the process confirmed our hypothesis that in all cases the increase in the soot yield was proportional to the appearance of an additional amount of CH3 radicals, which promoted the formation of propargyl, benzene and pyrene. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon black/ferrocene mixture can be an photo-triggered ignition agent. • Addition of ferrocene to carbon black enhances the effect of photoflash-ignition. • Carbon black/ferrocene can function as ignition agent for gaseous fuel. • Carbon black/ferrocene can function as ignition agent for energetic materials. The study proposes a new ignition agent composed of a mixture of carbon black and ferrocene, which can be triggered using a flash lamp. This low-cost alternative to costly materials like carbon nanotubes, fullerenes, or energetic metal nanoparticles, involves adding a tiny amount of ferrocene to carbon black to ignite gaseous fuels and other energetic materials. The carbon black generated by the laminar diffusion flame of acetylene can be ignited using the commercial camera flash. Scanning electron microscope and high-resolution transmission electron microscopy observations reveal that the carbon black used in the study has no distinct single-walled carbon nanotubes, multi-walled carbon nanotubes, or graphene structures. The flash-ignition test showed that the carbon black could be ignited with an ordinary camera flash lamp, with the oxidation reaction becoming more vital as the camera-flash energy output increases. Additionally, the flash-ignition reaction becomes more intense with finer carbon black particles, even with the camera flash lamp's energy output remaining the same. Furthermore, adding ferrocene to carbon black enhances the effect of flash ignition. The study evaluated the carbon black/ferrocene mixture using thermogravimetric analysis and spectrophotometer to determine its purity, ignition temperature, and photo-physical properties. It also measured the burning of the mixture with the Two-color Pyrometry, finding that the burning temperature of the proposed ignition agents was high enough to ignite the gaseous fuels and the energetic materials. Finally, the mechanism of ferrocene in promoting the flash ignition of carbon black is proposed. [ABSTRACT FROM AUTHOR]

Thermal plasma pyrolysis can realize direct synthesis of acetylene and carbon black from methane, while the yields of products vary according to the reaction conditions. In the present work, a pre-proposed detailed kinetic mechanism is applied to investigate the efficiency and product distribution of methane pyrolysis in thermal plasma. The kinetic mechanism is validated with experiments, which proves the reliability of the mechanism under the conditions of thermal plasma. From simulation results, higher temperature and residence time in millisecond are beneficial for higher acetylene yield, while long residence time is beneficial for the production of carbon black. To be specific, when the temperature is higher than 2100 K, conversion of methane is above 99 wt% and the yield of acetylene is above 80 wt%, which is referred to as the selective synthesis of acetylene from methane. When temperature increases, the proper residence time for the maximum acetylene yield would decrease to within one millisecond. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to synthesize a new kind of conductive grease which possesses a prominent conductive capacity and good tribological properties.Design/methodology/approach A two-step method was used to prepare complex lithium-based grease. Ketjen black (KB), acetylene black (AB) and carbon black (CB) were characterized by transmission electron microscope and used as lubricant additives to prepare conductive greases. Conductive capacity was evaluated by a conductivity meter, a surface volume resistivity meter and a circuit resistance meter. Tribological properties were investigated by a reciprocating friction and wear tester (MFT-R4000). The worn surfaces were analyzed by a scanning electron microscope, Raman spectroscopy, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscope.Findings The conductive grease prepared with KB has a prominent conductive capacity at room temperature, 100°C and 150°C. Further, this conductive grease also possesses better tribological properties than AB and KB greases. When the concentration of KB is 1.8 Wt.%, the coefficient of friction and wear width reduced by 11 and 14 per cent, respectively.Originality/value This work is a new application of nanometer KB as a lubricant additive in grease, which provides a direction for preparing conductive grease. The conductivity and tribology experiments have been carried out though the variation of experiment conductions. [ABSTRACT FROM AUTHOR]

High-rate acetylene black (AB) decorated NiCo 2 S 4 hollow microsphere is prepared via a gas bubble soft template and hydrothermal methodology. Benefiting from the combined advantages of the AB with high conductivity and the nanopetals assembled NiCo 2 S 4 with unique hollow micro-/nano- structures, abundant porosity and high conductivity, the as-obtained composites are found to exhibit high specific capacitances (768 F g −1 at 2 A g −1 ) and remarkable rate capabilities (92.2, 80.1 and 70.3% of capacity retention rate at 20, 50 and 100 A g −1 ). The fabrication mechanism of the AB-NiCo 2 S 4 composite is also proposed. Furthermore, an asymmetric supercapacitor is fabricated by using the AB-NiCo 2 S 4 composite as a positive electrode and activated carbon as a negative electrode. Owing to the excellent electrochemical properties of the AB-NiCo 2 S 4 electrode, the asymmetric device delivers high energy density (24.7 Wh kg −1 ) at a power density of 428 W kg −1 or high power density (17.12 kW kg −1 ) at a reasonable energy density of 7.1 Wh kg −1 , and exceptional cycling stability (105.6% of the initial capacity retention at 5 A g −1 over 5000 cycles). These results above demonstrate the significance and great potential of mesoporous NiCo 2 S 4 hollow microsphere-based composites in the development of high-performance energy-storage systems. [ABSTRACT FROM AUTHOR]

Hollow graphitic carbon nanoparticles (HGCNs) obtained by catalytic graphitization of acetylene carbon black (ACB) were investigated using ultra-soft X-ray emission spectroscopy. The electronic structures of the ACB HGCNs were compared with those of HGCNs obtained from iron carbide-filled carbon nanocapsules (Fe3C@CNCs) and Q-graphenes. The occupation of the π sub-band decreased in the following sequence: Fe3C@CNC HGCNs > ACB HGCNs > Q-graphenes. This sequence can be explained by changes in the occupations of the C2p states due to the formation of bonds between carbon and residual metal atoms within the HGCNs. It was also found that the contribution of the overlapping ofppπ+ppσ-states in the ACB HGCN walls toward the spectra of the HGNCs was greater in comparison with the reference Q-graphenes. It was established that ACB was not fully transformed into the HGCNs. Scanning and transmission electron microscopy methods were used to study the spatial structures and morphologies of the fabricated HGCNs. [ABSTRACT FROM PUBLISHER]

Acetylene synthesis conditions in methane pyrolysis on a tungsten wire heating element have been investigated. At high temperatures, methane pyrolysis yields a large amount of carbon black as small particles and carbon filaments. Carbon black practically does not form when methane is diluted with helium. At methane concentrations of 10-15% and coil temperatures of 1800-2000°C, 80% methane conversion and 80% acetylene selectivity have been attained at a contact time of a few hundredths of a second. Changing from pure methane to natural gas in the specified temperature range exerts no effect on the methane conversion and acetylene selectivity. It has been experimentally demonstrated that the reaction ceases on the gas temperature is decreased below 800°C. [ABSTRACT FROM AUTHOR]

Electrochemical behaviors of methocarbamol (MET) at the bare carbon paste electrode (CPE), acetylene black (AB) modified carbon paste electrode (AB/CPE), an ionic liquid 1-Benzyl-3-Methylimidazole hexafluorophosphate ([BnMIM]PF6) modified carbon paste electrode ([BnMIM]PF6/CPE) and AB-[BnMIM]PF6 modified carbon paste electrode (AB-[BnMIM]PF6/CPE) in PBS (pH = 6.8) were investigated by cyclic voltammetry (CV) and square wave voltammetric (SWV). The experimental results showed that MET at the above metioned four electrodes showed an irreversible electrochemical oxidation process, but at the AB-[BnMIM]PF6/CPE, the oxidation peak potential keep almost constant and the oxidation peak current of MET increased greatly. At the same time, the electrochemical kinetic parameters were determined. Under the optimized electrochemical experimental conditions, the oxidation peak currents were proportional to MET concentration range from 4.0 x 10-5 to 1.0 x 10-2 mol L-1 with the detection limit (S/N = 3) of 1.5 x 10-6 mol L-1. The proposed method was successfully applied in the determination of MET content in commercial tablet samples. [ABSTRACT FROM AUTHOR]

Abstract: Nitrogen-doped acetylene carbon black (N-C) is prepared by annealing acetylene carbon black and melamine under the protection of N2 at different temperatures. The resultant N-C materials are used as the support of Pd catalyst (Pd/N-C) for formic acid electrooxidation (FAEO). The catalytic activity of the Pd/N-C catalyst towards FAEO is evaluated by cyclic voltammetry, COad stripping voltammetry and chronoamperometry. The results show that when the heat-treatment temperature of support is 900 °C, the corresponding catalyst, Pd/N-C-900, generate 2.84-fold and 0.96-fold higher activity than homemade and commercial Pd/C catalysts in 0.5 M H2SO4 and 0.5 M HCOOH solution. The COad stripping voltammetry results demonstrate that Pd/N-C-900 has much better resistance to CO poisoning. Moreover, the effect of formic acid concentration and the temperature on the Pd/N-C catalysts are also explored, which confirms the really enhanced performances for FAEO. It is founded that the doping of nitrogen results an increase in the performance for FAEO due to the improved Pd nanoparticles (Pd NPs) dispersion and the modified electronic effect. The results indicate that the Pd/N-C catalyst has great application prospect as a high-performance anode catalyst for direct formic acid fuel cells (DFAFCs). [Copyright &y& Elsevier]

Abstract: A mixture of benzene and acetylene is pyrolyzed in an inert atmosphere to investigate the influence of the benzene–acetylene composition on the configurations of carbon black. The effects of benzene concentration, acetylene concentration, and furnace temperature on the mean primary particle diameter and the aggregate shape in carbon black are investigated. When the acetylene concentration is varied and the benzene concentration is made constant, aggregate shapes become complex with an increase in acetylene concentration. However, in the case where the acetylene concentration is greater than that of the benzene concentration, the variation of aggregate shapes is small with increasing acetylene concentration. The results of this study suggest that nucleation has progressed and aggregate shapes appear complicated when the ratio of the benzene concentration to the acetylene concentration is appropriate (in this study, the ratio is 2:1) and the furnace temperature is high. However, when the benzene or acetylene concentration is high, and the furnace temperature is low, aggregate shapes are simplified because of the formation of small polycyclic aromatic hydrocarbons (PAHs), which contributes to surface growth. [Copyright &y& Elsevier]

We report on a composite matrix composed of epoxy copolymers P (GMA-co-MPC) and acetylene black that can be used to entrap cytochrome P450. The composite provides a biocompatible microenviroment and can substantially accelerate the electron transfer between the cytochrome P450 and the electrode. The electrochemical response is characterized by a pair of well-defined redox peaks for the heme Fe(II/III) redox couples were observed at −483 mV (vs. SCE). The immobilized cytochrome P450 exhibits excellent electrocatalytical activity to diethylstilbestrol (DES). The amperometric response varied linearly with the concentration of DES in the 0.2 to 2.8 μM concentration range. The biosensor displays a detection limit 5.9 × 10 mol L and thus represents a promising candidate for studying the electrochemistry of cytochrome P450s and its sensing applications. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Composites of polypropylene filled with carbon black or acetylene black at different concentrations were prepared by melt mixing followed by compression molding. The influences of filler type and filler concentration on the composites conductivity were studied. It was found that the percolation threshold is located at a lower concentration in composites filled with the acetylene black, than that of the composites filled with carbon black. The model of Mamunya gives a fairly good agreement in the evaluation of the conductivity of polymeric composites loaded with carbon black or acetylene black, beyond the percolation threshold. The Boltzman equation was adopted to develop a model that represents more faithfully all results obtained. The expressions of the electrical conductivity, calculated with the model developed, are in good agreement with experimental results for the entire concentration range studied in linear or semilogarithmic scale. [ABSTRACT FROM AUTHOR]

Abstract: With an aim to construct a sensing platform for the electrochemical detection of paeonol, we modified the glassy carbon electrode with acetylene black nanoparticle (AB). A sensitive oxidation peak of paeonol was observed with remarkably increased peak current on the modified electrode because the electrode has a big surface area due to three dimensional structure of AB nanoparticles. The optimization of detection conditions was performed, including pH value of the buffer, the amount of AB nanoparticles on the electrode surface, the accumulation potential and time of paeonol. Under the optimized conditions, the oxidation peak current of paeonol increased linearly with its concentration over the range from 5×10−7 to 1×10−4 M. The detection limit was calculated to be 1×10−7 M. The modified electrode was successfully applied to detect the content of paeonol in cortex moutan, a common traditional Chinese medicine. The method is new, sensitive, rapid and convenient for the detection of paeonol. [Copyright &y& Elsevier]

Abstract: A novel acetylene black-PTFE cathode for electrogeneration of hydrogen peroxide (H2O2) was fabricated using acetylene black powder (ABP) as catalyst, PTFE as binder. The effect of mass ratio of ABP to PTFE, solution pH (3–11), applied current density (5–20mAcm−2) and surface hydrophobic property on the activity and useful life of cathode was investigated using a two-electrode undivided cell fed with air at 2Lmin−1 in Na2SO4 solution of 0.05M, and the characteristics of cathode were examined by FTIR spectra, BET measurement, SEM image and CV study. The experimental results showed that: (1) so far the activity of cathode is the highest for the electrogeneration of H2O2 with air feed, at pH 3 and the current density of 20mAcm−2 the average H2O2 generation rate reaching 58.9mgL−1 h−1 cm−2 during 150min of electrolysis and the current efficiency being 92.7%; (2) a proper and stable surface hydrophobic property could significantly increase the useful life of cathode; (3) the cathode had a remarkable restoration and regeneration performance. [Copyright &y& Elsevier]

Abstract: Solar methane dissociation appears as a possible route toward a hydrogen-based economy. The competitiveness of the process strongly depends on the carbon black properties and economic value. At CNRS-PROMES, a 50kW tubular solar reactor was developed to produce carbon black and hydrogen from methane. The reaction was carried out in a graphite receiver crossed by seven graphite tubes heated up by concentrated solar radiations at the 1MW CNRS solar furnace. The temperatures ranged between 1608K and 1928K and the methane flow-rates varied from 10.5 to 21NL/min. Total methane dissociation was reached with hydrogen yield higher than 80% and the carbon yield was drastically affected by the acetylene by-product. The carbon samples were analysed in detail and their properties were compared to a commercial conductive grade carbon black. Transmission electron microscopy showed primary particles of 10–70nm diameter. The crystallinity of the samples was characterised by Raman spectroscopy. It was also possible to correlate the specific surface area with the reaction temperature and with the concentrations of residual methane and of the acetylene by-product. The resistivity and the structure of the agglomerates were determined by simultaneous measurements of the conductivity and the density under compression. [Copyright &y& Elsevier]

Abstract: The work presents preliminary studies with the goal to extend the share of long graphene ribbons in laser-synthesized carbon black. Investigations revealed the existence, as a major constituent, of graphene ribbons composed of up to 10–15 graphene layers, spaced at ∼0.35–0.37nm and of tens of nanometres in length. The samples used to study the development of this specific structure were obtained from sensitized acetylene-based mixtures and the experiments were performed following the variation of both the experimental parameters and gas composition. [Copyright &y& Elsevier]

Abstract: Correlations between the electrochemical double layer capacitances of various acetylene blacks modified by surface oxidation and heat treatment, and their morphologies are presented. The acetylene blacks were different from each other in primary structural unit size (equivalent to mean particle diameter). They were oxidized in air at 300°C for 1h to produce graphene sheets protruding from the surfaces of the spherical particles. In addition, the surfaces of the acetylene blacks were modified by heat treatments from 1000°C to 2800°C, which resulted in a morphological change from surfaces covered with protruding graphene sheets to ones wrapped with basal planes of graphite. Correlations between the capacitances of the acetylene blacks and the observed morphologies showed that the surface covered with protruding graphene sheets was roughly 10 times more effective in capacitive charging than the surface of graphite basal planes. Specifically, the surface specific capacitance of the edged-graphene-sheet-covering surface was 146mF/m2, while that of the basal-planes-wrapping surface was 16mF/m2. It was concluded that the capacitances of the acetylene blacks were mainly defined by surface morphology, which were in turn influenced by structural unit size and degree of oxidation. [Copyright &y& Elsevier]

Acetylene can be directly produced by coal pyrolysis in hydrogen plasma. A key factor affecting acetylene yield is whether the residue solid carbon is able to react with hydrogen to form acetylene after volatile matters released from coal powders pyrolyzed in hydrogen plasma. Reactions of carbon in hydrogen plasma are studied in this article. The study showed that solid carbon could hardly react with hydrogen at temperatures below the sublimation point, while sublimated carbon could easily react with hydrogen at temperatures above sublimation point, and mainly acetylene and other hydrocarbons can be obtained after quenching process. [ABSTRACT FROM AUTHOR]