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This study presents the results of a bibliometric scientific literacy analysis on science education subjects. The main objectives of this study are (1) to analyze trends in scientific publications on scientific literacy in science education subjects; (2) identification of networks between authors, institutions, and countries; and (3) to understand the structure and focus of research and teaching themes of scientific literacy on science education subject. This research uses 451 published documents from 2018-2022 from the SCOPUS database. VosViewer software is used to analyze and visualize research data. The results of the research show (1) scientific publications on the topic of scientific literacy in science education subject have increased significantly in the last five years; (2) research results on this topic are published in reputable scientific journals (ranked Q1 and Q2); (3) United States is the country with the highest number of documents, citations, and institutions; and (4) there are six groups of keywords used, namely scientific literacy, science education, nature of science, students, education, and teacher education. This study recommends that research at the primary and secondary education levels by taking into account aspects of SL traits can be carried out in future research.

The main objective of this study was to map (1) the research of metacognition in science learning; (2) learning interventions used and metacognition’s key components that learned, integrated, and investigated; and (3) future research recommendations of metacognition research in science learning. We analyzed 438 scientific documents published in journals and books indexed in the Scopus database using VOSviewer software to visualize research trends and main keywords investigated of metacognition in science learning. The research findings show that research in the field of metacognition in science learning through the metacognition as attribution that integrated into learning interventions and as a learning outcome has increased in the last two decades. Scientific concepts understanding, critical thinking skills, motivation, and attention are the main goals in metacognition research. Inquiry-based learning, such as problem-based learning, is the most frequently used intervention to teach students metacognition. The research gaps found are (1) the cognitive regulations are the most investigated aspect, while cognitive aspects such as declarative knowledge, procedural knowledge, and conditional knowledge have not been widely investigated in science learning; (2) metacognition research on college students has a high frequency compared to school students; and (3) the integration of metacognition in online learning is still less investigated, this is indicated by the recommendations of several research results that encourage the integration of self-regulated learning into online learning.

Plant extracts have been shown to effectively inhibit the corrosion of metals. Using the Box-Behnken, gravimetric, and electrochemical techniques, analyses were designed to investigate the anti-corrosion potential of okra in a 1M HCl medium. The inhibition performances derived from the various methods were in good agreement, demonstrating that physio-chemisorption was effective and adhered to the Langmuir isotherm. The efficiency of okra mucilage powder was 96% at a much lower concentration, compared to 91.2% and 88.4% for the unsieved extract and gelly-okra filtrate, respectively. FTIR results showed the presence of several functional groups that promoted adsorption, and TGA analysis revealed that the extract had high thermal stability. The FESEM analysis also revealed evidence of adsorption. It was determined that corrosion inhibition by okra mucilage extract was primarily influenced by temperature, followed by extract concentration, with immersion time having the least effect. From the model optimization goal, 200ppm, 60°C, and 24h for 89.98% IE gave a high desirability. The results showed the high capacity of okra as an efficient biodegradable corrosion inhibitor.

Three metal chloride anion based ionic liquids (MCABILs) were synthesized and characterized for high conversion of hydrogen sulfide (H2S).

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Our world is facing continued challenges of environmental and ecological pollutions due to human and industrial activities. One of the major threats is oily wastewater mainly discharged from oil fields, refineries, automobile, palm oil industries, and many others. Membrane-based technology offers an almost complete separation of oil from water. However, the technology is facing the challenge of maintaining performance over long periods of operation caused by membrane fouling as a result of interaction between oil droplets and the membrane surface. This attracts research interest mainly on developing customized polymeric, ceramic well as a metallic-based membrane material for improved performance. This paper reviews the recent advances of membrane material developments with the focus on methods of improving the surface chemistry, structure, and hydrodynamics and their implication on the filtration performances.

Desublimation-based Carbon dioxide (CO2) removal from the natural gas (NG) in a cryogenic packed bed becomes challenging due to the dry ice formation inside the packed bed. Therefore, the cryogenic packed bed has been used for NG purification only in batch processes. However, to fulfill the energy requirements, it is crucial to develop a continuous process for NG purification, which is difficult for a single cryogenic packed bed. In the current research, a novel cryogenic packed bed system is proposed for continuous capture of desublimation based CO2 capture from natural gas. The process feasibility of the switching concept was proved through dynamic simulation and experimental study on CO2 separation from multi-component NG. It was observed that increasing CO2 content decreases the switching and saturation time of the cryogenic packed bed. The total energy required per packed bed per cycle in the switching system is 133.35. The saturation time for pure CO2 feed, NG sample-1, and NG sample-2 were 300, 500, and 600 s, respectively. An excellent agreement was observed between the results obtained from the experimental results and that obtained through dynamic simulation. A switching time of 200 s was found for a CO2 recovery of more than 98 %. This research work offers scientific data and theoretical support for the industrial application of switched cryogenic packed bed setup in CO2 capture from natural gas in the future. Moreover, in the current research work, scale-up study, and automatic control system for the switched packed bed are recommended for the future.

This work reported on the fabrication of mixed matrix membranes by incorporating NH2-MIL-125 (Ti) nanofiller into 6FDA–durene polymer matrix for CO2/CH4 separation. The structural properties and morphology of the nanofillers and resultant membranes were investigated by X-ray diffraction, Brunauer Emmett and Teller, field emission scanning electron microscope, energy-dispersive X-ray spectroscopy mapping, thermogravimetric analysis and free fractional volume. The results showed that the CO2 and CH4 single gas permeability, as well as CO2/CH4 ideal selectivity were improved by incorporating NH2-MIL-125 (Ti) into the polymer matrix. Membrane loaded with 7.0 wt% of NH2-MIL-125 (Ti) filler showed the highest CO2 permeability of 1115.70 Barrer and CO2/CH4 selectivity of 37.10, surpassing the 2008 Robeson upper bound. Furthermore, improvement of CO2 permeability of 119% and increment of 331% for gas pair selectivity in comparison with pure membrane were achieved. The results obtained in this work is due to the high porosity of nanofillers besides the attraction of amine functional group towards CO2. Overall, incorporation of amine-functionalized MIL-125 (Ti) nanofillers into 6FDA–durene polymer matrix has enhanced the separation performance of the membrane in CO2/CH4 separation.

The presence of high CO2 content in natural gas reservoirs is one of the significant threats to the environment. Cryogenic CO2 capture technology is amongst the emerging technologies used for natural gas purification before customer use. In this research work, the binary CO2-CH4 mixture having 75% CO2 content is studied. Aspen Hysys simulator with Peng Robinson property package is used for the prediction of phase equilibrium data for the binary mixture. The data obtained through the Aspen Hysys simulator is optimized for the S-V two-phase region for maximum CO2 capture. Response surface methodology is used for the optimization of the predicted data. Optimization of the pressure and temperature conditions is done to obtain maximum CH4 in the top stream and minimum CO2 with minimum energy requirement. In this research work, the pressure and temperature ranges selected from the predicted phase equilibrium data for the optimization are 1 to 20 bar and-65 to-150 °C respectively. At atmospheric pressure and-123.50 °C, the desirability value is maximum, which is 0.843. under these conditions, the CO2 and CH4 in the top product stream are 1070.72 Kg/hr and 152.04 Kg/hr respectively with an energy requirement of 2.087 GJ/hr.

Density of the hydrates plays an important role in penetrating the layers of water above hydrate for gas hydrate inhibition and dissociation. This paper discusses the density of Tetraethylammonium Bromide (TEAB) and Tetraethylammonium Iodide (TEAI) as the preliminary screening steps before implementing them in pipeline conditions. Densities of aqueous TEAB and TEAI solutions (0.5, 1.0, 2.5, 5.0 and 10.0 wt %) were investigated at atmospheric pressure over a range of temperature between 293.15 K to 313.15 K. The relationship of density with temperature and concentration are discussed. The molar volume of the solutions with respect to the temperature is also calculated from the experimental value of the density. The results indicate that TEAI with the higher density can be an efficient hydrate inhibitor especially in vertical pipelines.

The use of low-cost adsorbents produced from rice husks that can selectively remove zinc (II) ion from wastewater effluent has been investigated. The disorder and fatal diseases can be triggered in living organisms by accumulating the heavy metals in the wastewater. Adsorption is an operative cleansing and separation method used in the industry to remove contaminants from effluents. In order to convert the rice husk to the adsorbent, digestion and carbonization processes were performed. Rice husks digested nitric acid at 1.0 M to reduce the organic constituents and further carbonized at 400, 600 and 800 °C to eliminate the non-carbon element in rice husks. The physiochemical characteristics of the digested and carbonized rice husks were analyzed using scanning electron microscope (SEM), X-ray diffraction (XRD) and atomic adsorption spectrophotometer (AAS). The SEM morphological characteristics showed the high pyrolysis effect on the organic matter left the samples with more pores and cavities, which enhanced the surface area and uptake, especially for 800 °C carbonized samples. The samples’ physical characteristics using XRD showed that the treatment with HNO3 illustrated a pattern close to the activated carbon with slightly lower intensities. The applied feed-forward back-propagation neural network algorithm showed high validity (R2 ≈ 0.9686) for the tested experimental data sets and hence can be applied for forthcoming studies with nearby conditions. The outcomes showed that the increment of the carbonization temperature is correlated with the contact time and can increase the metal uptake percentage and adsorption capacity. The adsorption followed the Langmuir isotherm, which indicates monolayer coverage. The data showed that adsorption kinetics follow the pseudo-second-order rate expression.

A compatibility and stability of Isoreticular Metal Organic Framework (IRMOF-1) impregnated with choline based ionic liquids (ILs) are studied by molecular dynamic simulation. Among three proposed IL/IRMOF-1 hybrid composites, cholinium formate, ([Chl][Fm]) is nominated as the best IL to be incorporated with IRMOF-1 since it shows the lowest RMSD value (0.502 nm, 0.637 nm, 0.923 nm) at three IL/IRMOF-1 w/w ratio (0.4%, 0.8% and 1.2%) respectively and become representative to all three ILs. Oxygen atom in the bridging carboxyl group shows the most flexible atom through RMSF analysis since it shows the highest fluctuation (1.001 nm) at WIL/IRMOF-1 = 0.4%. The RDF shows that the interaction between [Chl]+ and [Fm]− is higher in composite phase compare to bulky phase due to confinement effect of IRMOF-1. Both [Chl]+ and [Fm]− seem to be preferred to locate around carboxylate group inside the IRMOF-1 whereby [Fm]− shows the dominant interaction and strongly interacts with IRMOF-1 compared to [Chl]+. In terms of mobility, the cation shows high mobility with SDF value of 0.0419 nm2 in which mobility is expected to be increased with increasing of ILs ratio (0.4%, 0.8% and 1.2%) respectively. Intensity of the ions population around IRMOF-1 is interpreted by density map which is in agreement with the RDF analysis. Finally, the stability of the IRMOF-1 is confirmed by the radius of gyration (Rg) analysis in which 0.4% ILs shows the most stable conformation with the lowest Rg value = 1.667 nm that is in consistent with the RMSD analysis. Overall, the structural stability of IRMOF-1 is well interpreted and impregnation of ILs literally increase the stability of framework at lower IL/IRMOF-1 w/w ratio.

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Ionic liquids, which are extensively known as low-melting-point salts, have received significant attention as the promising solvent for CO

One of the major emerging disasters for aquatic life as well as humans, is an oil spill. Aerogels are a suitable alternative for the cleaning of the oil spill cause of their outstanding characteristics. In this study, a facile method was presented for the production of aerogels from cellulose/lignocellulose using ionic liquids. This method is sustainable as it employs greener materials. Aerogels were prepared using sol–gel reaction with ionic liquids following gelation, and freeze-drying for 24 h. In the initial work, 1-Ethyl-3-Methylimidazolium Acetate [Emim][Ac] and 1-Butyl-3-Methylimidazolium Chloride [Bmim][Cl] were used. The resultant aerogels possess an interconnected porous structure depending upon the type of ionic liquid employed. The TGA and FESEM results suggest that aerogels using [Bmim][Cl] possess better thermal stability and porous structure as compare to [Emim][Ac]. The removal efficiency of [Bmim][Cl] was 84% which was 12% higher than [Emim][Ac] based aerogels.

In process industry, failure or rupture of pressurized vessel is very dangerous especially when there is an escape of flammable gaseous mixture that can cause potential fire or explosion. One of the scenarios that causes such accidents is the blowdown process. Therefore, it becomes crucial to control blowdown process to prevent such accidents. It is important to design optimally to make sure that blowdown valve is according to the requirements. For the safe use of a pressure relief system, some of the parameters are critical, for example, selection of construction material, sizing of relief valves, temperature, and pressure, etc. There is no literature currently available that discusses all the mathematical models or simulation tools for optimum design of the blowdown process. This subject matters because the available models or tools cover different aspects of blowdown process. A meticulous review is required to present the applications of these models and tools based on the accidental scenarios. Therefore, this paper critically reviews the models and tools that are developed purposely to calculate optimum blowdown parameters based on fluid and vessel conditions. Recommendations are given for the development of new simulation tool to simulate phase change conditions especially when solid formation is involved.

Monomeric ionic liquids (ILs), ionic liquid polymers (ILPs) and IL-based composites have emerged as potential materials for CO2 capture owing to their exceptional intrinsic physical solubility of CO2. This study reports the development of novel IL polymer materials incorporating CO2-philic tunable nanopores and their subsequent utilization for CO2 capture. In this approach, primarily, micelles were formed in monomeric IL 1-vinyl-3-ethylimidazolium bis(trifluoromethylsulfonyl)imide using a CO2-philic surfactant (N-ethyl perfluorooctyl sulfonamide) through self-assembly, from which polymeric materials were fabricated via free radical polymerization. The CO2 adsorption studies demonstrated 3-fold enhancements for the surfactant micelle incorporated IL polymers (SMI-ILPs) compared to their bare IL polymers. The SMI-ILPs were regenerated by simply heating at 70 °C and reused for 15 cycles with a retention of over 96% of CO2 uptake capacity. The simple recovery and notable enhancements in CO2 sorption of novel SMI-ILPs were traced to the adsorption of CO2 at the (i) highly porous IL-based polymeric networks, and (ii) nanometer sized apolar pores made by CO2-philic surfactant tails. This work will open up new possibilities for the development of IL based smart materials for CO2 capture and separation.

The uses of rice husk are constantly increasing since the last decay. Rice husk is a by-product attained from agricultural activities and has a potential use as a bio-sorbent for the adsorption of heavy metal ions, for example, lead removal from water and other aqueous solutions. The basic objective of this research is to synthesis environment-friendly adsorbent using rice husks. The study also investigated the effects of rice husk treatment on the elimination of Pb(II) ion from aqueous solutions. The results of adsorption capability also been related to the commercial activated carbon (CAC). Rice husks were treated in a few processes which were the pretreatment of raw rice husks, chemical activation, and carbonization process. Subsequently, it was characterized using X-ray diffraction (XRD) and SEM. The structure of the adsorbent using rice husks is found to be amorphous. Based on the treated rice husks characterization, the optimum carbonization temperature is found to be 600 °C. Temperature alteration showed 50–60% weight loss, with up to 3.475% removal. Artificial neural network modeling was applied to predict the experimental data sets using feed forward back-propagation neural network (FFBPNN) and Levenberg–Marquardt (L–M) training algorithm. The customized neural network was applied to emphasize the predicted adsorption capacity and removal/uptake percentage of the investigated bio-sorbents. The outcomes from the artificial neural network model showed high validity of the predicted data compared to the initially examined experimental data sets. The adsorption efficiency increases with the increment of carbon presence ratio in the adsorbent. The adsorption measurements are well presented by the Langmuir isotherm. The kinetic modelling revealed that the adsorption of Pb(II) ions followed the pseudo-second-order models. The reported results in this work can deliberate the rice husks as a potential alternative to commercial adsorbents with lower cost and better environmental aspects.

The increasing global energy demand has compelled the researchers to utilize the undeveloped contaminated natural gas (N.G) reservoirs. However, due to the emissions standards established by environmental regulatory authorities, N.G treatment has become more crucial. Amongst the established CO2 separation strategies, the cryogenic CO2 removal techniques are promising due to environmentally friendliness, high N.G purification, low footprint values, no chemical reaction involved and capable of handling N.G with high CO2 content. Design and operation of a cryogenic process require accurate thermodynamic knowledge along with the understanding of the phase behavior of CO2 with light alkanes to make the process cost–effective. Furthermore, the study of frosting and liquefaction behavior of CO2 or CO2–alkanes mixture is significant for the energy minimization and smooth operation of the cryogenic CO2 removal from N.G. This paper provides a critical review of the available experimental and predicted thermodynamic data for CO2–alkanes mixtures at different conditions. The significance of pressure–temperature (PT), pressure–composition (P–xy), and temperature–composition (T–xy) phase diagrams for CO2–alkane mixtures are discussed in this paper. This paper also describes the use of the equation of states (EoS) for predicting the thermodynamic phase behavior of the CO2 mixtures. This review will help the researchers in designing more efficient, economical, and sustainable cryogenic CO2 capture processes.

Phytosynthesis of gold nanoparticles (AuNPs) has achieved an indispensable significance due to the diverse roles played by biomolecules in directing the physiochemical characteristics of biosynthesized nanoparticles. Therefore, the precise identification of key bioactive compounds involved in producing AuNPs is vital to control their tunable characteristics for potential applications. Herein, qualitative and quantitative determination of key biocompounds contributing to the formation of AuNPs using aqueous Elaeis guineensis leaves extract is reported. Moreover, roles of phenolic compounds and flavonoids in reduction of Au3+ and stabilization of AuNPs have been elucidated by establishing a reaction mechanism. Fourier-transform infrared spectroscopy (FTIR) showed shifting of O─H stretching vibrations toward longer wavenumbers and C═O toward shorter wavenumbers due to involvement of polyphenolic compounds in biosynthesis and oxidation of polyphenolic into carboxylic compounds, respectively, which cape nanoparticles to inhibit the aggregation. Congruently, pyrolysis-gas chromatography-mass spectrometry revealed the major contribution of polyphenolic compounds in the synthesis of AuNPs, which was further endorsed by reduction of total phenolic and total flavonoids contents from 48.08 ± 1.98 to 9.59 ± 0.92 mg GAE/g and 32.02 ± 1.31 to 13.8 ± 0.97 mg CE/g within 60 Min, respectively. Based on experimental results, reaction mechanism explained the roles of phenolic compounds and flavonoids in producing spherical-shaped AuNPs.

CO 2 capture using cryogenic packed beds with spherical glass packing material has great potential for applications in the natural gas industry. However, the influence of packing material on their performance has been rarely studied. In the present work, some novel packing materials, including Cellulose Acetate and CA/NH 2 −MIL−101(Al) were used to enhance the performance of the cryogenic packed bed. Pressure drop was determined as a function of specific surface area and module filling fraction experimentally. The CO 2 capture efficiency of the system, axial temperature profile study during cooling and CO 2 recovery steps for the spherical glass beads, CA hollow fibres and composite CA/NH 2 −MIL−101(Al) hollow fibres were also investigated. It was found that the hollow fibres reduce the pressure drop by a factor of 61 % and 33 % compared with the pressure drop caused by the spherical glass beads and monofilament fibres, respectively. The specific surface area provided by the hollow fibres was 230 % and 122 % more than that offered by the glass beads and monofilament fibres respectively. It was also observed that the CO 2 capture efficiency of composite hollow fibres was 141.9 % more than spherical glass beads and 9.5 % greater than the pure CA hollow fibres. The temperature profile study reveals that pure CA and the composite CA/NH 2 −MIL−101(Al) hollow fibres require less energy for cooling than glass beads and provides higher bed saturation time. It was concluded that the NH 2 −MIL−101(Al) hollow fibre reduces the pressure drop and capital cost along with increasing the CO 2 capture efficiency.