Hybrid nanocomposites of aluminium (NHAMMCs) made from AA5052 are fabricated via stir casting route by reinforcing 12 wt% Si3N4 and 0.5 wt% of graphene for usage in aeronautical and automotive applications due to the lower density and higher strength to weight proportion. The wear characteristics of the NHAMMCs are evaluated for different axial load, rotational speed, sliding distance and sliding time based on Box-Behnken design (BBD) of response surface methodology (RSM). Orowan strengthening mechanism is identified from optical image which improves the strength of the composite. Outcomes show that with higher axial load and rotational speed, there is substantial increase in wear loss whereas with increased sliding distance and sliding time there is no considerable increase in wear loss due to the lubricating nature of the reinforced graphene particles since it has higher surface area to volume ratio. Besides, artificial intelligence approach of neuro-fuzzy (ANFIS) model is developed to predict the output responses and the results are compared with the regression model predictions. Prediction from ANFIS outplays the regression model prediction.

Modification of the surface of raw activated carbon using chemical solvents can significantly improve the adsorption performance of activated carbon. Triethylenetetramine is one of the most important chemical solvents used to modify raw activated carbon for formaldehyde removal indoor. We conducted the liquid impregnation experiments at different initial concentrations, temperatures, adsorbent dosage and time ranges to fully investigate the adsorption of triethylenetetramine on the surface of raw activated carbon for modification. We found that the Langmuir isotherm model and pseudo-first-order kinetic model fit quite well with the experimental data and the R2 are 0.9883 and 0.9954, respectively. The theoretical maximum adsorption capacity is 166.67 mg/g. The change in Gibbs free energy (ΔG0), enthalpy change (ΔH0) and entropy change (ΔS0) were also calculated to study the direction and driving force of the liquid adsorption process. In order to understand the adsorption process at the molecular level, a new activated carbon model based on the actual physical and chemical properties of activated carbon was carefully established in the Materials Studio to simulate the liquid-phase adsorption. The pore structure, elemental composition, functional group content, density, pore volume, and porosity of the activated carbon model converge close to the actual activated carbon and the adsorption isotherms obtained from the simulation agree well with the experimental results. The results show that the adsorption of triethylenetetramine on activated carbon is a spontaneous, endothermic and monolayer physical adsorption process.

Although the phenomenon of lead categories is well-documented in the marketing literature, our understanding of this important store choice factor remains limited. Lead categories are defined as those product categories that are so important for the shopping trip that they influence the consumer’s store choice decision. The purposes of this paper are to offer theoretical bases that explain why lead categories form and to understand how overall images of product quality, selection, and price affect lead category formation. The authors use theories of anchoring effects and automatic cognitive processing to offer theoretical explanations regarding why consumers form lead categories and how overall images of product quality, selection, and price affect lead category formation. Using survey data collected from consumers at two grocery stores, the authors find that positive overall product quality and selection images facilitate lead category formation and that an overall low-price image hinders it.

Customer value co-creation behavior (CVCB) has been regarded as a strong predictor of firm performance in many industries for decades. CVCB—the customer’s direct and indirect contribution of resources to enhance the offering of the focal agent/object—is ubiquitous in service industries. Recently, customer engagement has been identified as a determinant of the value realized by customers and businesses. Customer psychological engagement (CPEngagement) is a multidimensional customer-firm relationship marked by customer satisfaction and emotional connectedness to the firm. Although there is concurrence that customer engagement and CVCB are linked, scholars diverge as to the precise nature of the relationship. Marketing and hospitality literature have not yet developed an integrated model of customer engagement with the digital and physical components of hospitality services. Given the increasing managerial interest in digital customer engagement and value co-creation behaviors, it is essential to enhance our understanding of the interplay between these concepts and their implications for both consumers and businesses. This research investigates the relationship between CPEngagement and value co-creation in the digital and physical aspects of hospitality services.

This research presents a conceptual framework for a comprehensive understanding of the causes of user migration from social media networking sites. The results of our survey show that users’ intentions to switch social media platforms are influenced by user satisfaction, alternative attractiveness, peer influence, and perceived switching costs.

In today’s world, carbon-based materials research is much wider wherein, it requires a lot of processing techniques to manufacture or synthesize. Moreover, the processing methods through which the carbon-based materials are derived from synthetic sources are of high cost. Processing of such hierarchical porous carbon materials (PCMs) was slightly complex and only very few methods render carbon nano-materials (CNMs) with high specific surface area. Once it is processed, which paves a path to versatile applications. CNMs derived from biological sources are widespread and their application spectrum is also very wide. This review focuses on biomass-derived CNMs from various plant sources for its versatile applications. The major thrust areas of energy storage include batteries, super-capacitors, and fuel cells which are described in this article. Meanwhile, the challenges faced during the processing of biomass-derived CNMs and their future prospects are also discussed comprehensively.

Graphene oxide/Iron III oxide (GO: Fe2O3) nanocomposites (NCs) have been topical in recent times owing to the enhanced properties they exhibit. GO acting as a graphene derivative has demonstrated superior features as obtainable in a graphene sheet. Furthermore, the attachment of oxygen functional groups at its basal and edge planes of graphene has allowed for easy metal/oxide functionalization for improved properties harvesting. Fe2O3 nanoparticles (NPs) on the other hand have polymorphic property enabling the degeneracy of Fe2O3 in different phases, thereby resulting in different physical and crystalline properties when used to functionalize GO. The properties of GO: Fe2O3 have been applied to supercapacitor energy harvesting, Li-ion batteries, and biomedicine. The enhanced properties are attributed to the adsorption and electronic structure properties of Fe atoms. In this review, the various synthesis used in the preparation of reduced/graphene oxide: Fe2O3 is discussed. As indicated in the considered literature, the XPS analysis suggests electronic bond interactions between C–C, C–O, C–Fe and Fe–C. The available report on UPS measurements further suggests the formation of mixed states emanating from  and  bonds. The discussed reports further suggest that the various applications based on the harvesting of electronic, electrical, and magnetic properties are due to the ionic and exchange interactions between the different orbital states of carbon, oxygen and iron. The challenges and future prospects of the synthesis and application of GO/Fe2O3 are examined. Graphical abstract showing the process of exfoliation, reduction and functionalization of graphite to produce reduced graphene oxide (rGO).

The ability to both assay the presence of, and to selectively remove ions in a solution is an important tool for waste water treatment in many industrial sectors, especially the nuclear industry. Nuclear waste streams contain high concentrations of heavy metals ions and radionuclides, which are extremely toxic and harmful to the environment, wildlife and humans. For the UK nuclear industry alone, it is estimated that there will be 4.9 million metric tonnes of radioactive waste by 2125, which contains a significant number of toxic radionuclides and heavy metals. This is exacerbated further by increased international growth of nuclear new build and decommissioning. Efforts to remove radionuclides have been focused on the development and optimisation of current separation and sequestering techniques as well as new technologies. Due to the large volumes of waste the techniques must be economical, simple to use and highly efficient in application. Magnetic nanoparticles (MNPs) offer a powerful enhancement of normal ion exchange materials in that they can be navigated to specific places using external magnetic fields and hence can be used to investigate challenges such as, pipework in preparation of decommissioning projects. They also have the potential to be fine-tuned to extract a variety of other radionuclides and toxic heavy metals. It has been demonstrated that with the right functional groups these particles become very strongly selective to radionuclides, such as Uranium. However, this new technology also has the potential to effectively aid nuclear waste remediation at a low cost for the separation of both radionuclides and heavy metals. In this work, we investigate the origin of the selectivity of superparamagnetic iron oxide nanoparticles (SPIONs) to Uranium by making systematic changes to the existing surface chemistry and determining how these changes influence the selectivity. Identifying the mechanism by which selected common nuclear related metals, such as Na(I), K(I), Cs(I), Ca(II), Cu(II), Co(II), Ni(II), Cd(II), Mg(II), Sr(II), Pb(II), Al(III), Mn(II), Eu(III) and Fe(III), are sorbed will allow for specific NP-target (nanoparticle) ion interactions to be revealed. Ultimately this understanding will provide guidance in the design of new targeted NP-ligand constructs for other environmental systems.

Рrecipitation of platinum group metals (Rh, Ru, Pd, so-called MPG) from the melt essentially affects the reliability of installations for vitrification of high-level liquid radioactive waste (HLW). To date, it is difficult to find an approach which allows simultaneous recovery of all three metals. The aim of our work was to select a sorbent that would provide simultaneous up to complete recovery of given metals. The following inorganic materials were tested as sorbents – yellow blood salt (YBS).and hexacyanoferrates of iron, aluminum, copper and nickel. The degree of metal recovery was studied is influenced by the temperature and concentration of nitric acid. Only palladium was completely recovered using YBS. At the same time, specially prepared iron hexacyanoferrate (HCF-Fe) under optimal experimental conditions recovers almost all Pd and more than 95% and 90% of Rh and Ru, respectively. The behavior of fission products, including the main dose-forming components of HLW (Cs, Sr) and Mo, U, Ag, REE) in the course of MPG recovery was studied. The experiments were carried using both multicomponent model solutions and real raffinates. Options for further management of the recovered metals have been worked out. Thus, the proposed method of metal recovery seems promising for the development of a technology for the removal of MPG from nitric HLW during the reprocessing of the spent nuclear fuel (SNF) before vitrification. The recovered metals can be probably used in various technological processes. Also, this method can provide the MPG recovery from low-concentration tail solutions.

The ultrasonic method is an alternative to the conventional route to produce structured carbon materials, offering the advantages of synthesis in a short period of time under room temperature. The main objective of this work is to synthesize a sulfonated mesoporous carbon catalyst from a phenolic resin composed of phloroglucinol and formaldehyde. The synthesis was performed by the soft-template method in an ultrasonic processor and the product was subsequently carbonized and sulfonated for application in the esterification model reaction. Functionalization with sulfuric acid of MCS5-6 h sample brought about a decrease in porosity but simultaneously resulted in the generation of functional groups of an acidic nature. The MCS5-6 h catalyst with a sulfonic density of 1.6 mmol g− 1, surface area of 402 m2 g− 1 and pore diameter of 10.6 nm maintained in mesoporous even after acid treatment. MCS5-6 h showed excellent activity in the esterification reaction with 95% oleic acid conversion. The recyclability of MCS5-6 h was satisfactory during five reaction cycles. The present work addressed a promising alternative for the synthesis of carbon catalysts using ultrasound irradiation, thus providing an alternative with a lower cost of time and energy for large-scale production.

The research on dye-sensitized solar cells (DSSCs) is in the advanced stage today. The only concern observed so far has been regarding its stability and efficiency. Its power conversion efficiency can be increased by incorporating various methods and materials based on nanotechnology. Several attempts have been employed to develop advanced methods for eco-friendly, commercially viable, and sustainable DSSCs to minimize the energy crisis in the future. Photoanode is one of the essential components of DSSCs that can be modified using different nanostructures to enhance its efficiency. The TiO2 nanoparticlebased photoanode with gold and silver has proven to be potent materials for getting efficient DSSCs. The plasmonic and quantum confinement effects also play a vital role in efficiency enhancement. In this review, we discuss numerous attempts made by researchers in the last decade to modify the photoanode and their progress. We also look at different types of nanostructures, such as quantum dots, metal oxide doping, layered structures, nanocomposites, and thin film formation, that improve the efficiency of DSSCs. Several methods were reviewed to modify photoanodes to optimize electron transportation, light scattering, trapping power, surface area, and reduce charge recombination. The trend in the efficiency enhancement of DSSCs using TiO2, Au, ZnO, Ag, and graphene nanostructures-based photoanodes have been explored in great detail.

In this work, we report a direct preparation of a few-walled carbon nanotube (FWCNTs) and NiMgAl composites namely FWCNT-NiMgAl by pyrolysis of waste high-density polyethylene (HDPE) plastic at 800 °C with NiMgAl-layered double hydroxide (LDH) as catalysts. The composite formation is carried out in a single step using our lab-developed pyrolysis reactor. The NiMgAl-LDH catalyst was prepared by co-precipitation method and the FWCNTs were grown on the NiMgAl-LDH catalyst with FWCNT yield of 10% and FWCNT-NiMgAl composite yield of 55% whose quality is determined by Raman ID/IG ratio of 2.57. The average outer and inner diameter of the FWCNT are found to be 5.5 nm and 2.9 nm, respectively, from TEM and 2.92 nm from the outer RBM (radial breathing mode) band, which indicates the formation of a few-walled CNTs. FWCNT-NiMgAl is used for the fabrication of flexible supercapacitor electrodes on a polyethylene terephthalate (PET) sheet which achieved a specific capacitance of 432 Fg− 1 in a wide potential range (ΔV = 2) at a scan rate of 5 mV s− 1 in 2 M KOH electrolyte with a high energy density of 240 Wh kg− 1, whereas NiMgAl displayed a capacitance of 200 Fg− 1 with an energy density of 111 Wh kg− 1. The diffusion-type charge storage mechanism (pseudocapacitance) is found to be dominant with contributions of 73.2% and 69.75% for NiMgAl and FWCNT-NiMgAl, respectively. The highest specific capacitance and energy density are obtained for NiMgAl in 2 M KCl and for FWCNT-NiMgAl in 2 M NaOH electrolytes. However, the largest potential window is observed in KOH electrolyte for both NiMgAl and FWCNT-NiMgAl with value of ΔV = 2 V. The electrode material shows good stability in acidic electrolytes and also shows good capacitive stability at high frequencies maintaining a phase angle of 70°. The present work is a novel approach to fabricate low-cost multifunctional carbon composite nanomaterials and will contribute to the research on low-cost waste-derived CNT composite preparation and its application in flexible energy storage devices.

The central theme of this work is the synthesis of single-walled carbon nanotubes (SWCNTs) through the chemical vapor deposition method (CVD). Single-walled carbon nanotubes are synthesized using catalyst-chemical vapor deposition of acetylene at 750 °C temperature. X-ray diffraction study gives a characteristic peak (002) at 26.55° corresponding to the existence of carbon nanotube confirms that the particles are crystalline in nature and hexagonal phase. An SEM and HRTEM outcome gives surface morphology of SWCNTs. The elemental composition was confirmed by EDAX. The ideal concentration of single-walled carbon nanotubes was used to design a novel electrochemical sensor for determining paracetamol (PA) using cyclic voltammetry. Electrochemical determination of paracetamol is described using a single-walled carbon nanotube modified carbon paste electrode (SWCNT/MCPE). The SWCNT/MCPE was used in this study to detect paracetamol electrochemically at pH 7.2 in a 0.2 M PBS with a scan rate of 50 mV s− 1. A single-walled nanotube modified carbon paste electrode was used to develop a sensitive and selective electrochemical technique for the detection of PA. The SWCNT/MCPE showed excellent electrocatalytic activity towards the oxidation of paracetamol in phosphate buffer solution. Therefore, with increased oxidation currents, the voltammetric responses of paracetamol at the bare carbon paste electrode are organized within cyclic voltammetric peaks.

The team has studied the relationship between the ability of the coals to be dissolved in crude anthracene oil and their composition. The coal samples taken from different deposits in Russia and Mongolia were characterized by different stages of metamorphism and tested by the Fourier transform infrared spectroscopy and Carbon-13 nuclear magnetic resonance. The data of a correlation analysis enabled us to find out that an amount of aromatic structures in coal macromolecules provided the main influence on the thermal dissolution of the coals. The middle-rank coals had the highest rates of coal organic matter transfer to liquid products. The data showed that the dissolution process was accompanied by destruction of weak bonds among aliphatic groups. The amount of methylene groups in the aliphatic part of coal macromolecules had a direct impact on conversion of the coal organic matter into soluble products.

The bituminous coal was extracted with different industrial solvents like coal tar (CT), heavy cycle oil (HCO) and with their blends to determine the influence of solvent type on the extract yield, composition, thermal behavior, properties such as solubility to toluene and quinoline. The extracts obtained at 380 °C represented pitch-like solid matter with the softening points of 72–127 °C depending on the solvent used. They were characterized using the elemental and group analysis, FTIR spectroscopy, TG-DTG thermogravimetry and liquid chromatography for benzo(a)pyrene concentration. Also, maltene fractions of some extracts were studied by GC–MS. The results showed coal dissolution and the properties of the extracts to differ greatly depending on the solvent used. Coal tar was more favorable solvent for coal dissolution than HCO. Good correlation between the extract aromaticity and the content of the toluene insolubles was observed. The maltene fractions of the extracts obtained with CT and CT blended with HCO consisted mainly of polycyclic aromatics, and that obtained with the HCO contained also large amount of aliphatic compounds. It was found that the amount of the carcinogenic benzo(a) pyrene (BaP) in the toluene soluble fractions of the extracts were different depending on the solvents used for extraction. The remarkable result was that the BaP concentrations in all extracts were much lower than in the solvents used.

진드기는 박테리아, 바이러스, 원생동물 및 균류를 포함한 다양한 병원체를 전달할 수 있는 감염병매개체이다. 진드기는 불리한 환경조건에 서도 생존할 수 있는 능력이 있으며, 흡혈이 필수적인 절지동물의 진화적 산물로써 비흡혈 기간이 장기간 지속되는 경우에도 생존이 가능하다. 특 히, 높은 온도와 낮은 습도 환경에서도 견딜 수 있는 수분 조절 메커니즘과 내열성의 생리적 특징은 진드기가 전 세계적으로 분포하도록 한 중요한 요인이다. 진드기의 침샘, 말피기관, 후장 그리고 뇌를 포함하는 여러 기관이 관여하는 물과 이온의 획득 및 배출은 복합적인 메커니즘에 의해 조절 된다. 진드기가 수분을 확보하는 주요 경로는 흡혈과정 또는 공기 중 수증기를 직접 포집하는 방식이며, 이와 더불어 진드기가 자연조건에서 맺힌 물방울을 직접 마시며 수분을 보충한다는 것이 최근 본 연구진의 연구를 통해 밝혀졌다. 물방울에서 획득된 수분은 진드기 침샘의 포도상 부위(유형 I) 또는 중장을 통해 체내로 흡수된다는 것이 형광물질 추적을 통해 확인되었다. 이 연구 결과는 진드기 방제 및 병원체 전파 억제를 위한 전략 개발에 새로운 방향을 제시하였다. 본 종설에서는 진드기 방제를 위한 잠재적 표적인 진드기의 수분조절 및 표피 배설의 생리적 메커니즘을 종합적으로 다 룬다.