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The purpose of this paper is to prepare a spherical modifier-modified activated carbon fiber of high specific capacitance intended for electrode materials of supercapacitor.

In this study, phenolic-based microspheres are taken as modifiers to prepare PAN-based fiber composites by electrospinning, pre-oxidation and carbonization. Pearl-chain structures appear in RFC/ACF composites, and pure polyacrylonitrile fibers show a dense network. The shape and cross-linking degree are large. After the addition of the phenolic-based microspheres, the composite material exhibits a layered pearlite chain structure with a large porosity, and the RFC/ACF composite material is derived because of the existence of a large number of bead chain structures in the composite material. The density increases, the volume declines and the mass after being assembled into a supercapacitor as a positive electrode material decreases. The specific surface area of RFC/ACF composites is increased as compared to pure fibers. The increase in specific surface area could facilitate the diffusion of electrolyte ions in the material. Owing to the large number of bead chains, plenty of pore channels are provided for the diffusion of electrolyte ions, which is conducive to enhancing the electrochemical performance of the composite and improving the RFC/ACF composite and the specific capacitance of the material. The methods of electrochemical testing on symmetric supercapacitors (as positive electrodes) are three-electrode cyclic voltammetry, alternating current impedance and cycle stability.

The specific capacitance value of the composite material was found to be 389.2 F/g, and the specific capacitance of the electrode operating at a higher current density of 20 mA/cm2 was 11.87 F/g (the amount of the microsphere modifier added was 0.3 g). Using this material as a positive electrode to assemble into asymmetrical supercapacitor, after 2,000 cycles, the specific capacitance retention rate was 87.46 per cent, indicating excellent cycle stability performance. This result can be attributed to the fact that the modifier embedded in the fiber changes the porosity between the fibers, while improving the utilization of the carbon fibers and making it easier for electrolyte ions to enter the interior of the composites, thereby increasing the capacitance of the composites.

The modified PAN-based activated carbon fibers in the study had high specific surface area and significantly high specific capacitance, which makes it applicable as an efficient and environment-friendly absorbent, as well as an advanced electrode material for supercapacitor.

The purpose of this paper is to prepare a new modified activated carbon fibers (ACFs) of high specific capacitance used for electrode material of supercapacitor.

In this study, the specific capacitance of ACF was significantly increased by using the phenolic resin microspheres and melamine as modifiers to prepare modified PAN-based activated carbon fibers (MACFs) via electrospinning, pre-oxidation and carbonization. The symmetrical supercapacitor (using MACF as electrode) and hybrid supercapacitor (using MACF and activated carbon as electrodes) were tested in term of electrochemical properties by cyclic voltammetry, AC impedance and cycle stability test.

It was found that the specific capacitance value of the modified fibers were increased to 167 Fg^-1 by adding modifiers (i.e. 20 wt.% microspheres and 15 wt.% melamine) compared to that of unmodified fibers (86.17 Fg^-1). Specific capacitance of modified electrode material had little degradation over 10,000 cycles. This result can be attributed to that the modifiers embedded into the fibers changed the original morphology and enhanced the specific surface area of the fibers.

The modified ACFs in our study had high specific surface area and significantly high specific capacitance, which can be applied as efficient and environmental absorbent, and advanced electrode material of supercapacitor.

The process of manufacturing an activated carbon nonwoven made by cotton fiber was investigated. The study was focused on cotton nonwoven formation, carbonization, activation, and characterization of the activated carbon nonwoven. Pyrolysis of the cotton carbonization was analyzed using TGA. There was a considerable decrease in weight loss in the region between 250°C to 400°C and the proper carbonized temperature was 400°C. The SEM examination indicated that the surface area of cotton fiber was increased significantly because the inside hollow of cotton fiber was widely opened and some small agglomerated particles were gasified after activation. Absorbability of the activated carbon nonwoven was evaluated using an instrument of inverse gas chromatography. Dispersive surface energy, specific free energy, and total surface energy all indicated this trend: Carbonized Cotton > Activated Cotton > Raw Cotton. The activated carbon nonwoven exhibited the potential for use as high adsorbent and absorbent materials. They are light weight and bulky, advantageous in protective clothing applications and other consumer and industrial applications.

The purpose of this paper is to present the results of interaction occurring during the exposition of some specific carbon textile materials obtained in laboratory conditions to beams of various laser types.

Carbon fabric materials – fiber, felt and cloth – obtained from different precursor materials and prepared at various process conditions (oxidized, partially carbonized, carbonized, graphitized), were exposed to pulses of various lasers (Nd3+: YAG, alexandrite, ruby).

Depending on the laser power, plasma and destructive phenomena occurred. In the case of an interaction between a Nd3+: YAG laser beam and specimens of thickness in millimeter range, the authors have estimated the threshold of the energy density for drilling and discussed the possible models of the interaction.

The results have implications in the estimations of quality as well as in the improvement of material processing, giving some new light to the changes of mechanical and optical constants of the material, as well as to the changes of carbon groups of the material, which would be useful for different types of modeling. Future research will be in the interaction of laser beams with various textile materials, where the investigation would cover the microstructure changes and the implications on cloth cutting and welding, concerning the damages as well as relief structures, specially renew for fs laser regimes.

The area of laser applications in the textile industry is supported by scientific and applicative exploration. However, fewer results are concerned with deep introspection into the microstructure of the damages considering the laser interaction with carbon fiber and other carbon-based textiles.

Cleanrooms are highly controlled enclosed rooms where air quality is monitored and ensured to have less contamination according to standard cleanliness level. Air filters are used to optimize indoor air quality and remove air pollutants. Filter media and filtering system are decided as per requirement. Depth filter media are mostly used in cleanroom filtrations. This paper aims to present a comprehensive review of the evolution of cleanroom filter media. It evaluates the advantages and disadvantages of air filter media. It is also studied which air filters have additional properties such as anti-microbial properties, anti-odour properties and chemical absorbent. Development and innovation of air filters and filtration techniques are necessary to improve the performance via the synergistic effect and it can be a possible avenue of future research.

This paper aims to drive the future of air filter research and development in achieving high-performance filtration with high filtration efficiency, low operational cost and high durability. Air pollutants are classified into three types: suspended particles, volatile organic pollutants and microorganisms. Technologies involved in purification are filtration, water washing purification, electrostatic precipitation and anion technology. They purify the air by running it through a filter medium that traps dust, hair, pet fur and debris. As air passes through the filter media, they function as a sieve, capturing particles. The fibres in the filter medium provide a winding path for airflow. There are different types of air filters such as the high-efficiency particulate air filter, fibreglass air filter and ultra-low particulate air filter.

Emerging filtration technologies and filters such as nanofibres, filters with polytetrafluoroethylene membrane are likely to become prevalent over the coming years globally. The introduction of indoor air filtration with thermal comfort can be a possible avenue of future research along with expanding indoor environment monitoring and improving air quality predictions. New air filters and filtration technologies having better performance with low cost and high durability must be developed which can restrict multiple types of pollutants at the same time.

The systematic literature review approach used in this paper highlights the emerging trends and issues in cleanroom filtration in a structured and thematic manner, enabling future work to progress as it will continue to develop and evolve.

The purpose of this paper is to evaluate the thermo‐physiological comfort of a knitted polyester (PES) fabric which contains activated carbon particles in the back‐side.

According to the manufacturer's intention, the activated carbon particles, added in the PES extrusion process, give permanent attributes to the garment, such as odour resistance, UV protection and evaporative cooling. These features should make the modified PES ideal for sportswear. Standard fabric characteristics (morphology, mass per unit area, thickness) have been evaluated for two similar fabrics, the one containing the modified PES yarn and the other one made of conventional PES yarn. The investigated thermo‐physiological properties were air permeability (AP), water vapour resistance (R_et ), thermal resistance (R_ct ), thermal conductivity and diffusion, drying rate, vertical wicking, horizontal liquid diffusion area and buffering capacity. They have been measured in controlled thermal and humidity conditions in a climatic chamber.

The modified fabric is more hydrophilic than the conventional one, thanks to the carbon particles sorption ability. Thus, the liquid management of the modified PES fabric was found to be better. On the other hand, liquid desorption was slow and the drying time was longer. Moreover, the dry heat and the vapour transfer were found slightly worse for the modified PES, probably due to the lower AP.

The paper shows a comprehensive fabric characterization of a functionalized fabric, highlighting the positive and negative effects of activated carbon particles on the liquid, vapour and heat management.

The purpose of this study is to ensure the safe use of carbon fiber composite pressure vessels in the nuclear industry environment.

This study investigated the degradation behaviors of carbon fiber reinforced composite (CFRP) using the specific corrosive media HF solution, with a focus on the damage to the surface epoxy layer. The degradation behaviors of CFRP in HF solution were examined by electrochemical methods and surface characterization, using HCl, NaCl and NaF solution for comparison.

The results showed that the specimen in HF solution will have a value of |Z|_0.01 Hz one order of magnitude lower, a substantially lower contact angle, more breakage of the surface epoxy and the stronger O─H peak and weaker C─O─C peak in the Fourier transform infrared spectrum, indicating severe hydrolytic damage to the surface epoxy.

The work focuses on the degradation damage to CFRP surface epoxy by specific corrosive media HF.

This study aims to activated carbon prepared from pistachio waste by using phosphoric acid as chemical activator agent. Activated carbon adsorbents were prepared from pistachio waste by using phosphoric acid as chemical activator agent.

The optimum conditions for the highest adsorption performance were determined by central composite design (CCD). The adsorbent was used for the adsorption of dye reactive black 5 (RB5), and the parameters affecting the adsorption were discussed like pH, initial concentration, contact time and adsorbent dosage. The adsorbent synthesized has been characterized by FTIR spectroscopy and scanning electron microscopy. The kinetic models including pseudo-first-order, pseudo-second-order and intraparticle diffusion with Langmuir and Freundlich isotherm models were applied to investigate the kinetic and isotherms parameters.

When the dye concentration is 10 mg/L, RB5 dye removal rates reach 87.5 per cent. Moreover, the adsorption process of RB5 follows the pseudo-second-order kinetics and the Freundlich adsorption isotherm.

This study provided a simple and effective way to prepare activated carbon adsorbents from pistachio wastes. This way was conductive to protect environmental from a huge amount of agricultural waste produced and subsequent application for removal of pollutants from aqueous solutions.

The activated carbon adsorbents are prepared via chemical activation, which is prepared with pistachio wastes. There are two main innovations: one is that the novel adsorbents are prepared successfully by waste and the other is that the optimized conditions are designed by CCD.

Nitrogen oxides (NO_x) have been considered as primarily responsible for many serious environmental problems. Removing NO is the key task to remove NO_x hazards. To clarify, NO removal process for pitch-based spherical-activated carbons (PSACs), an online prediction and optimization technique in real-time based on support vector machine algorithm in regression (support vector regression [SVR]) is discussed. The purpose of this paper is to develop a predictor and optimizer system on selective catalytic reduction of NO (SCRN) using experimental data and data-driven SVR intelligence methods.

Predictor and optimizer using developed SVR have been proposed. To modify the training efficiency of SVR, the authors especially customize batch normalization and k-fold cross-validation techniques according to the unique characteristics of PSACs model.

The results present that SVR provides a property regression model since it can linkage linear and non-linear process and property relationships in few experimental data sets. Also, the integrated normalization and k-fold cross-validation show a satisfying improvement and results for SVR optimization. The predicted results of predictor and optimizer in single and double factor systems are in excellent agreement with the experimental data.

SCRN-PO for predicting and optimization SCRN problems is developed by data-driven methods. The outperformed SCRN-PO system is used to predict multiple-factors property parameters and obtain optimum technological parameters in real-time. Also, experiment duration is greatly shortened.

During the last 20 years, interest in the closed adsorption heat pump and refrigeration systems has increased steadily. In this paper, consideration is given to aspects of adsorption refrigeration in terms of existing materials used in adsorption refrigeration, heat transfer characteristics of materials, and cost of materials and manufacturing.

The paper is a general review of adsorption refrigeration technology.

In recent years several papers have been published in this area and many aspects of the system have been addressed. Much effort has been devoted to enhance materials properties.

The paper provides information of value to those involved with heat pump and refrigeration systems technology.