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Honeysuckle is rich in cynaroside (Cy), but its extraction and purification are difficult due to its poor solubility in water. Therefore, nonionic surfactants were used to extract Cy from honeysuckle plants, enabling the formation of micelles that solubilized Cy in aqueous solution. The effects of temperature, extraction time, surfactant concentration, and the solid–liquid ratio on the extraction rate of Cy were investigated to determine the optimal extraction conditions. The cloud point effect of the optimal nonionic surfactant was exploited to separate the extracting solution into two distinct phases, which resulted in the concentration of Cy into the up phase. The phase containing the extracted Cy was then purified by metal complexation after phase separation using CaCl2 followed by EDTA, resulting in a purity of Cy of 93.7%. Surfactants have high biological safety, making the extraction process safer and more environmentally friendly. As a result, the process developed in this study enabled the efficient and environmentally friendly extraction of Cy from plants, which has potential value in the production of various medicines and health products containing natural botanicals, such as Cy. [ABSTRACT FROM AUTHOR]

Electroslag remelting (ESR) as a widely used procedure could refine metals to achieve high-quality properties. Channel segregation, also known as freckle, is one of the most harmful macrosegregation patterns in ESR ingots, resulting in poor tensile strength or toughness. However, the formation mechanism and the control strategy of channel segregation in the ESR process have not been fully investigated. Herein, a continuum macrosegregation model is established to investigate channel segregation formation of a 30CrMnSiNi2A alloy ingot with an average diameter of 720 mm. Firstly, the solidification path adopted in this article is validated with thermodynamic calculation results, and channel segregation results calculated from the proposed macrosegregation model are compared with experimental data. Then, the flow, solidification process, and macrosegregation during the ESR process are detailed studied. Furthermore, the formation mechanism of channel segregation including the position of R/2 and the growth direction of V-shape is proposed. Finally, the effect of the processing parameter (the melting rate) on channel segregation is discussed, and advice on using lower melting rates for decreasing channel segregation is provided. This proposed model could assist in further understanding the formation of channel segregation and setting suitable processing parameters for the desired products with high quality. [ABSTRACT FROM AUTHOR]

It has been challenging to test how proteins acquire specific metals in cells. The speciation of metalation is thought to depend on the preferences of proteins for different metals competing at intracellular metal-availabilities. This implies mis-metalation may occur if proteins become mis-matched to metal-availabilities in heterologous cells. Here we use a cyanobacterial MnII-cupin (MncA) as a metal trap, to test predictions of metalation. By re-folding MncA in buffered competing metals, metal-preferences are determined. Relating metal-preferences to metal-availabilities estimated using cellular metal sensors, predicts mis-metalation of MncA with FeII in E. coli. After expression in E. coli, predominantly FeII-bound MncA is isolated experimentally. It is predicted that in metal-supplemented viable cells metal-MncA speciation should switch. MnII-, CoII-, or NiII-MncA are recovered from the respective metal-supplemented cells. Differences between observed and predicted metal-MncA speciation are used to refine estimated metal availabilities. Values are provided as blueprints to guide engineering biological protein metalation. Investigating how proteins acquire specific metals in cells is challenging. Here, the authors use a cyanobacterial MnII-cupin (MncA) as a metal trap to test predictions of metalation, and determine metal-preferences by refolding MncA in buffered competing metals. [ABSTRACT FROM AUTHOR]

ABSTRACT Recent research has focused on innovative instructional shifts that aim to expand what constitutes science and engineering practices, exploring also how they can build on students' diverse language resources in science learning. However, few studies explore the intersections of elementary teacher preparation and the implementation of science and engineering practices through expansive and asset‐based approaches to language use. Through a qualitative case study conducted within a science methods course at a research university in the southeastern part of the United States, elementary preservice science teachers were positioned as agentive learners, engaging in modeling practices while leveraging their diverse language resources. Using multimodal interaction analysis (MIA), our study examined the meaning‐making processes of elementary preservice science teachers in the practice of modeling. Findings revealed three themes related to how the preservice science teachers engaged with diverse semiotic resources: (1) their use of physical manipulatives and other multimodal resources to develop meanings during the initial stages of model development, where they experimented with different ways to represent their understanding; (2) their ongoing reliance on multimodal and linguistic resources for refining and solidifying meanings as the model became more complex and comprehensive throughout the modeling process; and (3) their use of these meanings to interpret and engage with science texts. Implications include the importance of providing elementary preservice science teachers with professional learning opportunities that align with the envisioned science learning experiences of their future students, thus fostering equitable science teaching and learning with models and modeling. [ABSTRACT FROM AUTHOR]

The residual metallic impurities in the graphite oxide (GO) dominate their properties and have a negative influence on the potential applications. The swelling of the GO suspensions is mainly affected by electrostatic forces and special interactions between water molecules, metal ions and hydrophilic groups. Bivalent and trivalent cations give rise to ionic crosslinking of the charged network within the particles. The CaCl2 solution has the best purification effect. A new purification method is proposed in the purification process, the origin metal ions in GO suspensions are replaced by homogeneous metal ions first, and GO suspensions are desalted by electrodialysis device. Free ionic calcium is removed by electrodialysis, and only the calcium that interact with GO particles is remained. The content of fixed calcium is 0.0049 g/g (nearly clear) after washing with 1.5 mmol/L CaCl2 solution and electrodialyzing for 20 min. The new method improves the purification efficiency and save energy. [ABSTRACT FROM AUTHOR]

Quartz sand is a high-end raw material with excellent physical and chemical properties derived from quartz stone. China heavily relies on imports for quartz, with the proportion of high-purity quartz being low in the market. Therefore, it is strategically important to strengthen independent technological research and development to efficiently utilise China's quartz sand resources. This work summarises and explains the physical and chemical properties of quartz, including its chemical components, phase composition, element existing state and embedded particle size. It also summarised various physical purification methods, such as colour separation, scrubbing–grading desliming, gravity concentration, magnetic separation and flotation. The work focused on the two major chemical purification methods, hydrometallurgy and pyrometallurgy, and clarified the challenges and dilemmas in quartz purification, such as high energy consumption, incomplete impurity removal and environmental pollution. On this basis, a green and efficient purification process for quartz sand, combining nonfluorinated acid leaching and microwave roasting, was proposed. [ABSTRACT FROM AUTHOR]

Tailoring the surface structure of the mesoporous metal catalysts is pivotal for influencing both the catalytic activity and selectivity. Through the dealloying of bimetallic alloys, surface modification is achieved by dissolving unstable components, thereby forming a multitude of catalytically active sites. In this study, highly enhanced electrocatalysts are fabricated via chemical etching of mesoporous AuCu alloy nanoparticles prepared through the self‐assembly of micelles. The presence of large mesoporosity (>10 nm) with rich defect sites on the surface, along with the synergistic effect arising from the AuCu bimetallic alloy, effectively boosts electrocatalytic performance for the ethanol oxidation reaction. This strategy demonstrates a promising strategy to further enhance the catalytic performance of Au‐based mesoporous nanoparticles by eliminating the unstable metal component and refining the mesoporous structure with an abundance of various active sites. [ABSTRACT FROM AUTHOR]

The document provides biographies of various contributors in the field of biomedical engineering and related disciplines. It includes information about their research focus, academic affiliations, awards received, and notable achievements. The contributors come from diverse backgrounds and work on a range of topics such as stem cell engineering, tissue regeneration, and biomaterials. The document highlights the significant contributions made by these individuals to the field of biomedical engineering and their ongoing research efforts. [Extracted from the article]

This Tutorial Review acquaints chemists and metallurgists with the properties and industrial applications of methanesulfonic acid (MSA, CH3SO3H). Over the past quarter-century, MSA has garnered increasing interest as a reagent for green chemistry due to its strong acidity, while circumventing many of the challenges associated with handling concentrated sulfuric acid, hydrochloric acid, or nitric acid. Concentrated MSA is a non-oxidizing reagent, exhibiting high chemical stability against redox reactions and hydrolysis, as well as high thermal stability and limited corrosivity towards construction materials. It is colorless, odorless, and possesses a very low vapor pressure. MSA combines commendable biodegradability with low toxicity. It is extensively utilized as a Brønsted acid catalyst for esterification or alkylation reactions, and is employed in biodiesel production. The high solubility of its metal salts, the high electrical conductivity of its concentrated solutions, coupled with the high electrochemical stability of MSA and its anion, make MSA-based electrolytes beneficial in electrochemical applications. Examples include the electrodeposition of tin–lead solder for electronic applications and the high-speed plating of tin on steel plate for food cans. MSA-based electrolytes are used in redox flow batteries (RFBs). MSA offers a much safer and environmentally friendlier alternative to electrolytes based on fluoroboric or fluorosilicic acid. A novel application area is as a strong acid in extractive metallurgy, where it may contribute to the development of circular hydrometallurgy. MSA is being explored in lithium-ion battery recycling flowsheets, as well as in other applications in the field of metal recovery and refining. However, this review is not solely about the advantages of MSA for green chemistry or clean technologies, as there are also some potential drawbacks. Apart from its higher price compared to regular strong acids, MSA has only minor advantages for applications where sulfuric acid performs well. Since methanesulfonate biodegrades into sulfate, the same emission restrictions as for sulfate should be considered. In conclusion, MSA is the acid of choice for applications where metal sulfates cannot be used due to poor solubility or where concentrated sulfuric acid is too reactive towards organics. [ABSTRACT FROM AUTHOR]

Metallic alloy fuels from fast reactors will be reprocessed by a non‐aqueous electrochemical technique known as electrorefining. Electrorefining of spent metal fuel results in the accumulation of heat‐generating fission products, especially 137Cs in the eutectic salt. These fission products need to be removed from the salt so as to reduce the decay heat load and contamination. The melt crystallization technique is a simple separation process being pursued for the separation of fission products. This is a single‐step process that utilizes the difference in solubility of fission products in the solid and liquid phase. This process is also less energy intensive. Crystallization involves the purification of a substance from a liquid mixture by solidification of the desired component. Since separation is based on selective solidification, which involves phase change, it is essential to evaluate the transient solidification pattern, liquid fraction distribution, solute distribution, and separation time and efficiency. Numerical modeling of the separation of CsCl from a LiCl‐KCl eutectic mixture has been carried out using Ansys Fluent (19.2). The effect of crystallizer geometry and cooling rates on the separation of CsCl has been numerically simulated. [ABSTRACT FROM AUTHOR]

The ladle refining of iron-carbon melts is an essential component of the modern technology used in the production of iron and steel, ensuring the high quality of metal products. However, in the context of mini- and micro-factories using technological units of a limited volume, it is often unfeasible to implement modern, highly efficient refining, deoxidation-alloying, and heating schemes that are commonly used by ladle furnaces and degassers. In addition, the issue of the widespread use of various production wastes for the production of cast iron and steel in order to recycle them and reduce the consumption of conventional charge materials is relevant. Therefore, a new method of submerged arc reduction of elements useful for metallurgy from industrial waste and secondary materials directly into an iron-carbon melt for its deoxidation-alloying (refining), homogenization, and heating by a submerged electric arc is proposed. This technology eliminates the use of expensive reagents, ferroalloys, and alloying elements. Based on the conducted research, a scheme of the processes of submerged arc reduction of elements was established, the design of submerged arc furnace assemblies and their composition were proposed, and the high efficiency of the new method of ladle refining in comparison with conventional analogs was demonstrated. [ABSTRACT FROM AUTHOR]

Industrial wastewater sludge is one of the vital sources of metals, including heavy metals, valuable metals, and precise metals. Apart from metals' necessity and economic value, some are toxic and harmful to the environment. This review explores the technologies currently applied for extracting and recovering heavy metals from industrial wastewater sludge. The technologies have been explained, and the merits and demerits of methods, as reported in past investigations, have been highlighted. The salient findings of this review are that the hydrometallurgical processes using acid leaching (H2SO4, HNO3, HCl, etc.) have been considered for the metal extraction process. Metal dissolution, concentration/purification, and recovery are the main stages of hydrometallurgical processes. The selection of successive metal recovery methods depends on the concentration of metals and chemical characteristics of industrial wastewater sludge. Different metal purification and concentrations were reported, including adsorption, ion exchange solvent extraction, and so forth, while precipitation and electrodeposition were mainly applied for metal recovery from industrial wastewater sludge. In this review, the cost and economic viability of the metal recovery process are also evaluated by previous reported studies. This review may be considered a valuable source of information for environmentally friendly and cost‐effective methods for metal recovery from industrial wastewater sludge. [ABSTRACT FROM AUTHOR]

The viscoelastic dampers (VEDs), which can provide both stiffness and damping, have been recently introduced into the field of structural vibration control for seismic enhancement of civil engineering structures. In this study, a kind of high damping acrylic polymer matrix VEDs (HDPVED) is developed independently, and this innovative HDPVED can solve the significant problem of service performance under medium‐high temperature environments, as well as low‐frequency vibration control under earthquake actions for civil engineering structures. To systematically investigate the influencing rules of frequency, temperature, and displacement amplitude on the mechanical properties and damping dissipation performance of HDPVEDs, a series of dynamic mechanical performance tests of the developed HDPVEDs are carried out at different frequencies, temperatures, and displacement amplitudes. The research results show that HDPVED exhibits excellent damping dissipation capability and adaptability under medium‐high temperature environments and low‐frequency excitations. The mechanical properties and energy dissipation performance present a strong correlation with frequency, temperature and displacement amplitude, and there is an obvious coupling effect between the three influencing factors. Based on the macroscopic mechanical property research of HDPVED, the microscopic damping mechanism and microscopic mechanical properties of HDPVED are then investigated. High‐order fractional derivative fraction Voigt and Maxwell model in parallel (FVMP) models are preferred to characterize the combined hyper‐elasticity and viscoelasticity owned by networked molecular chains and free molecular chains. The breaking and reconstruction theory of microphysical bonds is used to assess the effect of packing particles, and the time‐temperature equivalence principle is introduced to assess the effect of temperature. The multi‐scale refinement model is proposed, and the validity and accuracy of this model are verified by testing data of HDPVED. The study results show that the proposed model can accurately describe the effects of frequency, temperature, displacement amplitude, and microstructure on the multi‐scale mechanical properties of HDPVED. It provides a theoretical basis for the multi‐scale design and development of high damping VEDs. [ABSTRACT FROM AUTHOR]

The technology of recycling non-briquetted shavings of Kh18N10T steel by the method of electroslag crucible melting has been developed. Processing was carried out by joint melting of shavings with a consumable metal electrode from scrap metal of the same grade. It is shown that during such melting the metal is refined from extraneous impurities, has a low content of sulfur and gases, metal burning losses do not exceed 2 wt.%, and its chemical composition meets the requirements for Kh18N10T steel. Mechanical properties of metal plates with a thickness of 65...100 mm, obtained by electroslag melting of shavings and scrap of Kh18N10T stainless steel, significantly exceed the requirements of the technical conditions for cast thick-walled products. [ABSTRACT FROM AUTHOR]

In this paper, we designed the A356-B2O3-KBF4 reaction system to synthesize (AlB2 + Al2O3)/A356 biphasic particles-reinforced aluminum matrix composite with varying weight percentages (2%, 4%, 6%, and 8%). The synthesis was achieved through mechanical mixing and mixed salt reaction. We studied the friction and wear performance of the composite at room temperature using XRD, PC, SEM, EDS, laser confocal microscopy, and microhardness analysis. Our results indicate that the AlB2 and Al2O3 duplex-enhanced particles were effectively synthesized, with predominantly short rod morphology and local clustering observed for the AlB2 particles. The AlB2 particles were mostly in the micron-scale range, while the Al2O3 particles were mostly in the nanoscale range, both exhibiting agglomeration phenomena. Both enhanced particles showed an agglomeration phenomenon and could grow together with the interface binding very closely. At 6 wt.% mass fraction of biphasic particles, the composite exhibited the best refinement effect on-Al grains, as well as the greatest friction reduction effect and wear resistance for both the (AlB2 + Al2O3)/A356 composite and the A356 matrix alloy. The wear mechanism was primarily abrasive wear, while the A356 matrix alloy's wear mechanism was adhesive wear. [ABSTRACT FROM AUTHOR]

Steel quality, to a large extent, is controlled by ladle refining reactions. The understanding of such reactions can help to prevent the formation of unwanted phases and improve the overall high‐temperature process control. A new approach, namely, the multioxide inclusion kinetic model has been recently developed to simulate steel–inclusion reactions in liquid steel. The coupling of this kinetic model with a multicomponent, multiphase steel–slag reaction interface model leads to an overall model framework to predict the evolution of steel, slag, and inclusion composition. The current work shows the application of the model to simultaneous deoxidation and desulphurization during ladle refining of Si–Mn‐killed steel. The model shows good performance with industrial data. It is demonstrated that for ladle refining practices, silica‐rich slags should be strictly used with basicity (CaO/SiO2) between 1 and 1.2 and with Al2O3 content less than 5 wt%. Additional simulations are also carried out to reveal the capability of the model to aid in online process control. Finally, certain limitations of the current model are discussed. [ABSTRACT FROM AUTHOR]

Data mining by machine learning (ML) has recently come into application in heavy metals purification from wastewater, especially in exploring lead removal by biochar that prepared using tube furnace (TF-C) and fluidized bed (FB-C) pyrolysis methods. In this study, six ML models including Random Forest Regression (RFR), Gradient Boosting Regression (GBR), Support Vector Regression (SVR), Kernel Ridge Regression (KRR), Extreme Gradient Boosting (XGB), and Light Gradient Boosting Machine (LGBM) were employed to predict lead adsorption based on a dataset of 1012 adsorption experiments, comprising 422 TF-C groups from our experiments and 590 FB-C groups from literatures. The XGB model showed superior accuracy and predictive performance for adsorption, achieving R2 values for TF-C (0.992) and FB-C (0.981), respectively. Contrasting inferior results were observed in other models, including RF (0.962 and 0.961), GBR (0.987 and 0.975), SVR (0.839 and 0.763), KRR (0.817 and 0.881), and LGBM (0.975 and 0.868). Additionally, a hybrid dataset combining both biochars in Pb adsorption also indicated high accuracy (0.972) as obtained from XGB model. The investigation revealed that the influence of char characteristics and adsorption conditions on Pb adsorption differs between the two biochar. Specific char characteristics, particularly nitrogen content, significantly influence lead adsorption in both biochar. Interestingly, the influence of pyrolysis temperature (PT) on lead adsorption is found to be greater for TF-C than for FB-C. Consequently, careful consideration of PT is crucial when preparing TF-C biochar. These findings offer practical guidance for optimizing biochar preparation conditions during heavy metal removal from wastewater. [ABSTRACT FROM AUTHOR]

This paper presents the results of research conducted with the use of water physical model of refining ladle for production of high-carbon FeSi alloys. The purpose of the research was to determine the possibilities to enhance the efficiency of the production process by using combined gas injection into the bath. The research involved analysis of four variants of the experiment. Those variants varied in terms of the location of a purging plug fitted in the model bottom and the application of immersion lance to support the process. The research involved the analysis of changes in the hydrodynamic effects in the ladle model occurring as a result of the gas injection. The tests consisted in a qualitative analysis (process visualisation) in order to identify the movement of the modelling liquid and the mechanism of gas bubbles behaviour in the liquid. [ABSTRACT FROM AUTHOR]

Solar-driven interfacial evaporation is a sustainable and green desalination method with great prospects for development in today's severe water shortage problem. In this paper, a novel composite aerogel was prepared by hydrothermal method with sodium alginate (SA) and Cu2+ in the preparation process using reduced graphene oxide as photothermal material and cellulose nanofibers as substrate. The good hydrophilicity of nanocellulose makes the composite aerogel have strong capillary action and continuous water transport. The gel formed by ion exchange between SA and Cu2+ greatly improves dry and wet mechanical strength of the composite aerogel and ensures the stability of the evaporator for multiple recycling. Copper is doped by reduction of copper ion complexes and reduced graphene oxide have a synergistic effect to increase the photothermal response rate of the composite aerogel of 1.446 kg m−2 h−1 with evaporation efficiency of 84.87% under one standard solar irradiation. In addition, the purification of heavy metal ions, dye wastewater as well as acid and alkali solutions also has excellent results. It is expected that this study will provide some new ideas for the fields of seawater desalination and wastewater treatment. [ABSTRACT FROM AUTHOR]

The production of high-quality stainless steel strip and microcrystalline strip of special alloys directly from the melt on twin-roll continuous casters is an important strategic R&D topic in the steel industry. Analysis of the number and nature of published works on this topic in our country and abroad shows that research work is being completed. Experimental twin-roll casters built abroad have been tested in industrial conditions and put into operation. [ABSTRACT FROM AUTHOR]

This study explores the kinematic model of the popular RHex hexapod robots which have garnered considerable interest for their locomotion capabilities. We study the influence of tripod trajectory parameters on the RHex robot's movement, aiming to craft a precise kinematic model that enhances walking mechanisms. This model serves as a cornerstone for refining robot control strategies, enabling tailored performance enhancements or specific motion patterns. Validation conducted on a bespoke test bed confirms the model's efficacy in predicting spatial movements, albeit with minor deviations due to motor load variations and control system dynamics. In particular, the derived kinematic framework offers valuable insights for advancing control logic, particularly navigating in flat terrains, thereby broadening the RHex robot's application spectrum. [ABSTRACT FROM AUTHOR]

Gallium and indium are crucial metals in various industries, such as the medical and telecommunication industries. They can find applications as pure metals, alloys and alloy admixtures, oxides, organometallic compounds, and compounds with elements such as nitrogen or arsenic. Recovery of these two metals from waste is an important issue for two main reasons. First, gallium and indium are scattered in the Earth's crust and their minerals are too rare to serve as a primary source. Second, e-waste contributes to the rapidly growing problem of Earth littering, as its amount increased significantly in recent years. Therefore, it is essential to develop and implement procedures that will enable the recovery of valuable elements from waste and limit the emission of harmful substances into the environment. This paper discusses technological operations and methods that are currently used or may be used to produce pure gallium and indium or their oxides from waste. The first step was described—waste pretreatment, including disassembly and sorting in several stages. Then, mechanical treatment as well as physical, chemical, and physicochemical separations were discussed. The greatest emphasis was placed on the hydrometallurgical methods of gallium and indium recovery, to be more precise on the extraction and various sorption methods following the leaching stage. Methods of obtaining pure metals or metal oxides and their refining processes were also mentioned. [ABSTRACT FROM AUTHOR]

The Cas9 endonuclease of the CRISPR/Cas type IIA system from Streptococcus pyogenes is the heart of genome editing technology that can be used to treat human genetic and viral diseases. Despite its large size and other drawbacks, S. pyogenes Cas9 remains the most widely used genome editor. A vast amount of research is aimed at improving Cas9 as a promising genetic therapy. Strategies include directed evolution of the Cas9 protein, rational design, and domain swapping. The first generation of Cas9 editors comes directly from the wild-type protein. The next generation is obtained by combining mutations from the first-generation variants, adding new mutations to them, or refining mutations. This review summarizes and discusses recent advances and ways in the creation of next-generation genomic editors derived from S. pyogenes Cas9. Key points: • The next-generation Cas9-based editors are more active than in the first one. • PAM-relaxed variants of Cas9 are improved by increased specificity and activity. • Less mutagenic and immunogenic variants of Cas9 are created. [ABSTRACT FROM AUTHOR]

Hydrogen is increasingly acknowledged as a promising sustainable energy carrier to fulfill the global energy demand due to its superior energy density, cleanliness, and storability. Besides, it finds extensive application in various industries including oil refining, steel/metal production, chemical production, and transportation. Currently, greater than 95 % of H 2 is produced from fossil fuels or renewable resources with release of CO 2 as a by-product. To mitigate this CO 2 emission, extensive attempts have been undertaken to develop environmentally friendly H 2 production methods. The photocatalytic process stands out as a green chemical process, which can produce H 2 at atmospheric condition without the emission of CO 2 or other toxic substances. Due to its outstanding attributes such as high visible light absorption capacity and remarkable thermal-chemical resistance, black TiO 2 (bTiO 2) exhibiting defects is currently being developed and applied for photocatalytic H 2 production. This review focuses on the recent advancements in the laboratory-scale development of bTiO 2 , outlining several strategies including defective self-doping, metal and non-metal doping, and conductive material or semiconductor coupling. Among the various strategies applied, the coupling of bTiO 2 with semiconductors exhibited the highest photocatalytic H 2 production. The mesoporous TiO 2 /CeO 2 nanocomposite aerogel, synthesized by thermal treatment in 5 % H 2 /Ar atmosphere, produced approximately 182 mmol/g⋅h of H 2 under the visible light illumination. This review could broaden the horizon on the design and tailoring of bTiO 2 nanocomposites for further practical applications. • This review focuses on the recent laboratory-scale development of bTiO 2. • Four strategies have been conducted to improved the photocatalytic activity of bTiO 2. • Coupling of bTiO 2 with semiconductors provided the highest H 2 production. • Future synthesis of bTiO 2 -based materials should be focused on a "one-pot" method. [ABSTRACT FROM AUTHOR]

In sheet metal forming, persistent challenges such as failure, wrinkling, and springback necessitate innovative solutions. This study elucidates a novel methodology tailored to mitigate these prevalent defects. Our primary aim was to bolster formability while concurrently diminishing defects throughout the forming cycle. To realize this objective, we deployed a segmented and variable blank holder force (S-VBHF) trajectory, facilitating precise adjustments to the blank holder force (BHF). In our quest to optimize process parameters, encompassing the S-VBHF, friction coefficient, and drawbead restraining force (DBRF), we amalgamated deep neural network, genetic algorithm, and Monte Carlo simulation techniques, collectively denoted as DNN-GA-MCS. The forming limit diagram (FLD) served as our rigorous evaluative framework, enabling a comprehensive assessment of sheet failure dynamics during the forming phase. Our proposed methodology underwent stringent validation via numerical simulations, with the cylindrical cup from NUMISHEET 2011 (BM1) providing the benchmark. Empirical outcomes underscored substantial enhancements in formed sheet quality: marked reductions of 8.33% in failure, 10.81% in wrinkling, and 5.88% in springback. In summation, our advanced methodology manifests potential in refining sheet metal forming processes, emphasizing its efficacy in substantially curtailing defects. [ABSTRACT FROM AUTHOR]

Straw biochar, as an emerging adsorbent, boasts advantages such as abundant availability, renewability, and cost-effectiveness, making it highly promising in treating heavy metal wastewater. This paper presents a comprehensive review of the preparation methods for straw biochar materials, delves into the adsorption mechanism of straw biochar for heavy metals, discusses its application in heavy metal wastewater treatment, and also highlights areas for further in-depth research, including the adsorption mechanism, adsorption capacity, and regeneration performance, in lights of existing challenges in their preparation and application. This paper deepens the scientific understanding of the action mechanism of straw biochar in heavy metal wastewater treatment, and provides an important reference for the development of straw biochar materials and application of straw biochar materials in the purification of heavy metal wastewater. [ABSTRACT FROM AUTHOR]

Impurity and non-metallic inclusions control are imperative for the metallurgical quality of superalloys. In this paper, the effect of revert addition on the nitrogen removal and inclusion characteristics of GH4738 superalloy has been investigated. And a multiscale transient model for describing and predicting nitrogen removal from liquid superalloy during the refining process is developed by coupling macroscopic phenomena (including electromagnetic, fluid flow, heat, and mass transfer). A series of experimental data validate the reliability of the model. Results demonstrated that revert addition significantly suppressed the nitrogen removal efficiency and led to more nitrogen residue in the liquid superalloy, contributing to more nitrides or carbonitrides precipitation. The transient model shows that the residual nitrogen in the molten bath is spatially inhomogeneous distributed, in which the mass transfer of nitrogen between the gas–liquid interface is synergistically controlled by chamber pressure, bath temperature, and melt flow pattern. Increasing the refining power enhances the stirring intensity, which accelerates solute transport and facilitates nitrogen removal, but it also leads to a higher refining temperature that thermodynamically inhibits the denitrification reaction. Simulation results show that vacuum refining of revert superalloys by reducing the chamber pressure and increasing the metal bath stirring intensity is beneficial to obtain alloys with low nitrogen content. Considering the inhibitory effect of high temperature and revert addition, adjusting the refining power is recommended to promote nitrogen removal when the proportion of revert is more than 40 pct. [ABSTRACT FROM AUTHOR]

Design processes are always in motion, since more and more data-driven methods are used for various design and validation tasks. However, small and medium enterprises especially struggle with enhancing their processes with data-driven methods due to a lack of practical and easy-to-use analysis and redesign methods which can handle design process characteristics. In this paper, we present PADDME, which stands for process analysis for digital development in mechanical engineering, as a novel method that, in contrast to currently available analysis methods, considers those design process characteristics with respect to the integration of data-driven methods. Furthermore, a novel technology-readiness framework for digital engineering is introduced. Using the PADDME method, an industrial case study on introducing data-driven methods into the design and evaluation process chain is presented. The usability and novelty of the method are shown by the case study. Thus, PADDME allows a detailed capturing of current design processes and paves the way for process optimisation through data-driven methods. PADDME is a valuable method for advancing digital mechanical engineering processes in small and medium enterprises, and future work will focus on refining and expanding its application and evaluation. [ABSTRACT FROM AUTHOR]

Introduction: As a result of Industry 5.0's technological advancements, collaborative robots (cobots) have emerged as pivotal enablers for refining manufacturing processes while re-focusing on humans. However, the successful integration of these cutting-edge tools hinges on a better understanding of human factors when interacting with such new technologies, eventually fostering workers' trust and acceptance and promoting low-fatigue work. This study thus delves into the intricate dynamics of human-cobot interactions by adopting a human-centric view. Methods: With this intent, we targeted senior workers, who often contend with diminishing work capabilities, and we explored the nexus between various human factors and task outcomes during a joint assembly operation with a cobot on an ergonomic workstation. Exploiting a dual-task manipulation to increase the task demand, we measured performance, subjective perceptions, eye-tracking indices and cardiac activity during the task. Firstly, we provided an overview of the senior workers' perceptions regarding their shared work with the cobot, by measuring technology acceptance, perceived wellbeing, work experience, and the estimated social impact of this technology in the industrial sector. Secondly, we asked whether the considered human factors varied significantly under dual-tasking, thus responding to a higher mental load while working alongside the cobot. Finally, we explored the predictive power of the collected measurements over the number of errors committed at the work task and the participants' perceived workload. Results: The present findings demonstrated how senior workers exhibited strong acceptance and positive experiences with our advanced workstation and the cobot, even under higher mental strain. Besides, their task performance suffered increased errors and duration during dual-tasking, while the eye behavior partially reflected the increased mental demand. Some interesting outcomes were also gained about the predictive power of some of the collected indices over the number of errors committed at the assembly task, even though the same did not apply to predicting perceived workload levels. Discussion: Overall, the paper discusses possible applications of these results in the 5.0 manufacturing sector, emphasizing the importance of adopting a holistic human-centered approach to understand the human-cobot complex better. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue in the Journal of Inorganic & Organometallic Polymers & Materials. The issue focuses on the integration of metal-organic frameworks (MOFs) into 2D structures and their derivatives, highlighting their properties and applications in various fields such as catalysis, energy storage, optoelectronics, and more. The articles cover topics such as heavy metal purification, nanocomposites, graphene hybrid components, and electrochemical sensing activity. The issue also explores the challenges and future research perspectives in developing composite materials. The document concludes by mentioning other research areas covered in the issue, including sensing applications, packaging, 3D printing, photocatalytic applications, and more. [Extracted from the article]

This document is a summary of a special issue of the journal Metals titled "Advances in Molten Metal Refining Process." The issue includes ten articles that cover various aspects of molten metal refining processes, focusing on iron, steel, aluminum, magnesium, and titanium. The articles discuss topics such as the evolution of vortex structures in continuous casting molds, the excitation of micro-scale flow near the solid-liquid interface, the optimization of electrode insertion depths in magnesia furnaces, the behavior of hydraulic jumps during the continuous casting process, the bubble size distribution in single-snorkel furnaces, the refining process of slot-porous matched dual tuyeres, the desulfurization process in Kanbara reactors, the wear and efficiency of graphite rotors in aluminum refinement, and the prediction of bending forces in hot-rolled plates. The articles present mathematical models, numerical simulations, and experimental results to advance the understanding and optimization of molten metal refining processes. [Extracted from the article]

A mathematical model incorporating dynamic parameters is proposed to investigate the overall decarburization process during the vacuum oxygen refining (VOD) process for ultrapure ferritic stainless steel. This paper also conducted a precise theoretical calculation of the C‐Cr equilibrium. Moreover, the top‐blowing oxygen distribution is categorized into six directions: [C] oxidation, alloy component oxidation, CO bubble oxidation above the bath surface, bath surface oxidation (FeO), dissolution in the molten steel ([O]), and escape into the exhausted gas. The FeO and Cr2O3 oxide are intermediate product of oxygen to oxidize [C] remaining in the molten steel during the VCD stage. The modified approach of Gibbs free energies determines the critical carbon concentration by the distribution ratio of carbon to the top‐blowing oxygen. The top‐blowing oxygen primarily consumed by CO‐CO2 bubble (49–55%) and Cr2O3 (26–33%). Additionally, the model considered operational aspects, the system's heat balance, and changes in overall metal‐slag conditions during the refining process. The exhausted gas composition and end‐point carbon concentration align well with industrial data. Within a certain range (approximately up to 0.50%), increasing initial carbon concentration can enhance overall decarburization efficiency. [ABSTRACT FROM AUTHOR]

TiN, a typical nonmetallic titanium inclusion, is regarded harmful for the quality of hypereutectoid tire cord steel. At present, the effective methods of controlling the TiN inclusions in the high‐carbon tire cord steel are still uncertain. Herein, the precipitation and solid solution behavior of the TiN inclusions in SWRH92A tire cord steel are studied. The main characteristics, e.g., size distribution and morphology, of the TiN inclusions precipitated under different steel remelting conditions (e.g., Ti and N concentrations and cooling rate) are analyzed. The results indicate that the average TiN inclusion size is proportional to the Ti and N concentration product, and Ti shows larger effect on the TiN inclusion size than N. For the samples with heat treatment, the number percentage and average size of larger TiN inclusions decrease compared with reference sample. As heating temperature increases from 1150 to 1250 °C, the total TiN inclusion number decreases, and the number percentage and average size of larger TiN inclusions decrease. After heating, the sample with a higher cooling rate has a higher number percentage of finer inclusions and the average size of larger inclusions is smaller, indicating that increasing cooling rate is helpful to refining the TiN inclusions. [ABSTRACT FROM AUTHOR]

Metal-loaded liquid organic scintillators (MeLS) are discussed from the point of view of light yield at high metal loading (Gd, Nd, Zr, In). It is shown that, when metal -diketonates are introduced into the scintillator, its light yield is always lower than when carboxylates are used, which is explained by the structural difference between these complexes. The nature of the metal in some cases (Nd) also affects the light attenuation length and, consequently, the MeLS light yield. The composition of the solvent (the fraction of aromatics in the main solvent) and the degree of purification of the introduced metal complex also have a significant effect on the light yield. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office 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.)

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office 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.)

Chitosan (CS) is a non-toxic, biocompatible, and biodegradable deacetylated derivative of chitin. CS was effective metal-chelator; however, its practical application is restricted because of adsorption capacities, stability in acid medium, and adsorption selectivity. Because of the existence of amine (-NH2) and hydroxyl (-OH) groups, CS could be altered to make different derivatives with varying solubility pattern. Chitosan chemical modification and its derivatives by graft copolymerization could improve their properties and as a result expand their promising applications onto various fields. Carboxymethyl chitosan is one of the chitosan derivatives and it was most intensively explored because of its water solubility in broad pH conditions. However, it was employed in various promising applications. Carboxymethyl chitosan (CMCS) has soluble nature, hence it is difficult to use for metal ion removal studies. To overcome this problem, carboxymethyl chitosan was modified as insoluble hybrid material and was utilized for heavy metal removal studies by adsorption method. In this review, CMCS derivatives and its interaction with heavy metal ions were investigated in detail. It is hopefully predictable that the content will offer conclusive insights on the utilization of this biological activity, biodegradation, low-toxicity, and biocompatibility of CMCS and its interaction with various heavy metals for water purification and trust to boost up its promising application as heavy metals removal. [ABSTRACT FROM AUTHOR]

The dam of refiner plates directly affects the trajectory and speed of the pulp flow in the refining zone, and then the refining quality and energy consumption of the target pulp and fiber properties. However, less knowledge about it can be found in the literature. In this paper, from a theoretical point of view, first, two refining intensities of straight bar plates with dams were modeled: specific edge load (SELd) based on the equivalent total bar length and net tangential force per bar crossing zone (fτnet). Second, an analogous model of the evolution of average fiber length (Lf) and the pulp Schopper-Riegler (SR) versus net refining energy during the mixed softwood and hardwood pulp refining was elaborated. Low-consistency refining trials were performed on a pilot installation via four straight bar plates with different dam numbers and heights to validate the theoretical approach. The experimental results were explained through the established models for quantifying the evolution of the chosen pulp or fiber properties. Consequently, the fτnet was identified to be a proper refining intensity for interpreting the refining trials undertaken by straight bar refiner plates with and without dams. However, the SELd can only be used to characterize the refining process performed by straight bar plates with the same angular parameters. Furthermore, the calculated value of the pulp SR or fiber length throughout the established analogous model correlates well with the measured values, implying that the analogous mathematical evolution model of fiber length and pulp SR can be potentially applied to their prediction, as well as the optimization of the pulp refining process. [ABSTRACT FROM AUTHOR]

To date, reactor-grade zircon is produced on an industrial scale using metallothermic and electrochemical methods. Electrolytic production of reactor-purity zirconium in a sealed electrolyzer is more cost-effective than metallothermic production, as it does not require iodide refining and the use of reducing metals (Na, Mg, and Ca). Despite the importance of this production, its features are not fully described in the literature. This study presents the results of industrial tests of the electrolysis process in a sealed electrolyzer with a current load of 10 kA from the molten electrolyte KC1--KF--K2ZrF6. Based on the achieved technological indicators, the current efficiencies of the main cathode and anode reactions were determined and the factors influencing them were evaluated. We analyzed the composition of nutrient salts and the mechanism of accumulation of potassium fluoride in the electrolyte, an increase in which concentration leads to an anode-destroying effect. We considered possible mechanisms of the electrochemical formation of freons and compiled material balances for all starting substances and reaction products. The change in the electrolyte density during electrolysis was calculated, which allowed justifying the volume of its daily drainage. Fine carbon and zirconium powder formed in the electrolyte due to the interaction with potassium metal are not separated and are removed for chemical redistribution, which reduces the productivity of the electrolysis process. [ABSTRACT FROM AUTHOR]

In the secondary metals refining processes, vacuum arc remelting (VAR) and electroslag remelting (ESR), the consumable electrode is commonly produced by vacuum induction melting (VIM) which employs the regrettably primitive casting technique of simply pouring into the open top of the mold. Despite the vacuum, the resulting oxidizing conditions and the immensely powerful turbulence accompanying the top-pouring of the electrode is now known to create a substantial density of serious cracks. The cracks in the cast electrode are bifilms (double oxide films), which in turn are proposed to be responsible for the major faults of the VAR ingot, including undetectable, horizontal macroscopic cracks, white spots (clean and dirty varieties) and in-fallen crown. The remedial action to solve all these issues at a stroke is the provision of a counter-gravity cast electrode, cast in air or vacuum, or provision of any similar electrode substantially free from bifilm defects. The ESR process is also described, explaining the reasons for its significantly reduced sensitivity to the top-poured VIM electrode, but indicating that with an improved electrode, this already nearly reliable process has the potential for perfect reliability. The target of this critical overview is an assessment of the potential of these secondary refining processes to produce, for the first time, effectively defect-free metals, metals we can trust. [ABSTRACT FROM AUTHOR]

Spent lead–acid batteries have become the primary raw material for global lead production. In the current lead refining process, the tin oxidizes to slag, making its recovery problematic and expensive. This paper aims to present an innovative method for the fire refining of lead, which enables the retention of tin contained in lead from recycled lead–acid batteries. The proposed method uses aluminium scrap to remove impurities from the lead, virtually leaving all of the tin in it. The results of the conducted experiments indicate the high efficiency of the proposed method, which obtained a pure Pb-Sn alloy. This alloy is an ideal base material for the production of battery grids. This research was carried out on an industrial scale, which confirms the possibility of facile implementation of the method in almost every lead–acid battery recycling plant in the world. [ABSTRACT FROM AUTHOR]

The separation of praseodymium (Pr) and neodymium (Nd) is particularly challenging within the lanthanide series. A new strategy was developed for enhanced separation of Pr and Nd, using interfacial "push and pull" complexation induced by a kinetic effect. We found that the specific addition order of diethylenetriaminepentaacetic acid (DTPA) had an obvious influence on the separation behaviors of Pr/Nd. Notably, the separation coefficient was up to 3.25 with the addition of DTPA when the extraction process just started. This suggested that different complexation rates decided differences of extraction kinetics between Pr and Nd. It revealed differences in complexation rates of adjacent RE(III) with DTPA and dissociation rates of RE-DTPA complexes by stopped-flow spectrophotometry. The results indicated that the complexation rate constant of Nd3+ was higher than Pr3+. On contrary, the dissociation rate constant of Nd-DTPA was smaller than Pr-DTPA. Molecular dynamics (MD) simulations showed that the interfacial "push and pull" complexation effect led to differences in interfacial molecule arrangements and diffusion mass transfer rates near the interface. And thus, the separation of Pr/Nd can be enhanced. This research provides an efficient strategy for the purification of metals that are difficult to separate. [Display omitted] • Kinetic enhanced separation of Pr and Nd under "push and pull" complexation effect. • Competitive complexation of RE ions with [A336][NO 3 ] and DTPA. • Separation coefficients were affected significantly by the added order of DTPA. • Complexation kinetics were studied by stopped-flow spectrophotometry. • Study extraction kinetics via analysis of mean square distance based on MD. [ABSTRACT FROM AUTHOR]

In electric arc furnace (EAF) steelmaking, oxygen jets play a crucial role in controlling stirring ability, chemical reactions, and energy consumption. During the EAF lifetime, refractory wear leads to a decrease in the molten steel level and an increase in the nozzle-to-steel distance, thereby negatively affecting the overall energy efficiency of the process. The objective of this study is to optimize the energy efficiency of the EAF refining process by adjusting the nozzle flow conditions and conducting an analysis of jet performance using computational fluid dynamics (CFD) simulation. Three types of injection jets were considered: the conventional jet, the CH4 coherent jet, and the CH4 + O2 coherent jet. The findings reveal that the shrouded flame of the coherent jet enhances jet performance by maintaining the maximum velocity, extending the potential core length, and increasing the penetration depth in the molten steel bath. To maintain the jet performance in response to an increased nozzle-to-steel distance resulting from refractory wear, transitions from the conventional jet to the CH4 coherent jet and the CH4 + O2 coherent jet are recommended once the nozzle-to-steel distance increases from its initial level of 1000 mm to 1500 mm and 2000 mm, respectively. [ABSTRACT FROM AUTHOR]

A quarter scale water model experiment is employed to investigate the effect of single and double porous plug placement and blowing flow rates on the mixing time, slag eye area, and slag entrapment depth. As a result, when the blowing flow rate is greater than 180 L min–1, the blowing effect of double blowing plugs is better than that of single blowing plugs. The open eye area and slag entrapment depth in the double blow plug arrangement are smaller than that in the single blow plug arrangement. In general, the ladle refining effect is better when the blow plug is arranged at 0.4R position and the angle between the two blow plugs is 120°. The final recommended argon blowing process is 240–300 L min–1 for the heating and alloying process and 60–120 L min–1 for the soft blowing process, respectively. [ABSTRACT FROM AUTHOR]

To better control the multiphase vacuum refining process, a 3D (three-dimensional) comprehensive numerical model was established to study the melting behaviors of two alloy particles. Two melting mechanisms were proposed to represent the melting behaviors of two alloy particles in high-temperature molten steel. A species transport model was then developed to demonstrate the mixing of the alloy element based on the stable flow pattern. The results indicate that the melted alloy particle would be gradually mixed after 3-4 cycles of the recirculation of the molten steel during the refining process which takes approximately 200 seconds. The maximum mixing time increases from 181.8 to 220.4 seconds with the 70 pct Ti–Fe alloy particle diameter changing from 0.01 to 0.05 m. This computational framework could be used to understand the solid particle melting and composition distribution in the high-temperature melt. [ABSTRACT FROM AUTHOR]

The present work aims to boost our understanding of factors governing the grain-refining efficiency of inoculation treatments by comparing the grain-refining efficiencies of two inoculators: Ti nanoparticles and LaB6 nanoparticles, in a 2024 Al alloy during additive manufacturing (AM). Experimental results obtained by scanning electron microscopy show that the LaB6 nanoparticle possessed almost no refining effect on the alloy, with the addition content ranging from 0.5 wt.% to 2 wt.%. Conversely, the Ti nanoparticle resulted in a more pronounced refinement and a fine, fully equiaxed microstructure at 1 wt.% Ti addition. Based on transmission electron microscopy analysis, the higher refining efficiency of Ti inoculation was ascribed to the incorporation of both Ti solute and the in situ-formed L12-Al3Ti nucleation particles. The former significantly increased the overall undercooling ahead of the growing Al grain, which ensured the activation of heterogeneous nucleation on the L12-Al3Ti nanoparticles, leading to grain refinement. This work highlights that despite the addition of nucleation particles, the incorporation of appropriate solutes to generate sufficient undercooling is the prerequisite for the activation of heterogenous nucleation in AM. [ABSTRACT FROM AUTHOR]

Nitric acid (NA) is corrosive. On contact with the skin, liquid splashes with nitric acid and may produce severe burns. These burns usually take on a characteristic yellowish hue. We report the case of a 54-year-old man presenting a nitric acid burn with a pathognomonic skin lesion and perfect healing. NA is a chemical that is important in industry, and it is a very strong acid that is used for engraving, metal refining, electroplating, and fertilizer manufacturing. Skin contact with NA leads to severe burns. The pathophysiology depends on the type of concentration, the strength, quality, and duration of contact, and the penetration power of the acids concerned. The early and abundant irrigation with water or sterile isotonic saline solution, the use of panthenol-containing creams and covering with silver sulphadiazine dressing, carefully monitoring wounds, keeping wounds clean and moist, and preventing and managing secondary infection allow the healing. [ABSTRACT FROM AUTHOR]