Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume

Journal Name	Impact Factor	CiteScore	Launched Year	First Decision (median)	APC
Foods foods	4.7	7.4	2012	14.5 Days	CHF 2900
Materials materials	3.1	5.8	2008	13.9 Days	CHF 2600
Polymers polymers	4.7	8.0	2009	14.5 Days	CHF 2700
Sensors sensors	3.4	7.3	2001	18.6 Days	CHF 2600
Applied Sciences applsci	2.5	5.3	2011	18.4 Days	CHF 2400

2 pages, 134 KiB

Open AccessEditorial

Scientific Advances in STEM: Synergies to Achieve Success (Volume 3)

by Yadir Torres, Ana M. Beltrán and Manuel Felix

Appl. Sci. 2025, 15(6), 3030; https://doi.org/10.3390/app15063030 - 11 Mar 2025

Viewed by 117

“Scientific Advances in STEM: Synergies to Achieve Success, Volume 3” emphasizes the importance of interdisciplinary collaboration in Science, Technology, Engineering, and Mathematics (STEM) for driving innovation and societal benefits [...] Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

14 pages, 1842 KiB

Open AccessArticle

Prediction of Flotation Deinking Performance: A Comparative Analysis of Machine Learning Techniques

by Tamara Gavrilović, Vladimir Despotović, Madalina-Ileana Zot and Maja S. Trumić

Appl. Sci. 2024, 14(19), 8990; https://doi.org/10.3390/app14198990 - 6 Oct 2024

Cited by 1 | Viewed by 981

Abstract

Flotation deinking is one of the most widely used techniques for the separation of ink particles from cellulose fibers during the process of paper recycling. It is a complex process influenced by a variety of factors, and is difficult to represent and usually [...] Read more.

Flotation deinking is one of the most widely used techniques for the separation of ink particles from cellulose fibers during the process of paper recycling. It is a complex process influenced by a variety of factors, and is difficult to represent and usually results in models that are inconvenient to implement and/or interpret. In this paper, a comprehensive study of several machine learning methods for the prediction of flotation deinking performance is carried out, including support vector regression, regression tree ensembles (random forests and boosting) and Gaussian process regression. The prediction relies on the development of a limited dataset that assumes representative data samples obtained under a variety of laboratory conditions, including different reagents, pH values and flotation residence times. The results obtained in this paper confirm that the machine learning methods enable the accurate prediction of flotation deinking performance even when the dataset used for training the model is limited, thus enabling the determination of optimal conditions for the paper recycling process, with only minimal costs and effort. Considering the low complexity of the Gaussian process regression compared to the aforementioned ensemble models, it should be emphasized that the Gaussian process regression gave the best performance in estimating fiber recovery (R² = 97.77%) and a reasonable performance in estimating the toner recovery (R² = 86.31%). Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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15 pages, 3731 KiB

Open AccessArticle

Multi-Objective Optimization of Crashworthiness of Shrink Tube Energy Absorption Structure

by Fan Zou and Shuguang Yao

Appl. Sci. 2024, 14(16), 7347; https://doi.org/10.3390/app14167347 - 20 Aug 2024

Cited by 1 | Viewed by 930

Abstract

By means of material testing, truck testing and numerical simulation, the structural parameters of the shrink tube anti-climb device for high-speed trains were determined. The effects of cone angle, tube thickness, friction coefficient and axial length of the friction cone on the crashworthiness [...] Read more.

By means of material testing, truck testing and numerical simulation, the structural parameters of the shrink tube anti-climb device for high-speed trains were determined. The effects of cone angle, tube thickness, friction coefficient and axial length of the friction cone on the crashworthiness of the shrink tube were studied, and the main causes were analyzed. Using cone angle and tube wall thickness as input variables, and peak crush force, mean crash force and specific energy absorption as crashworthiness indexes, a proxy model was constructed using a radial basis function. The global response surface methodology was adopted to optimize the design of the shrink tube’s structural parameters. The results showed that the crashworthiness of the shrink tube was positively correlated with the cone angle, the thickness of the shrink tube and the friction coefficient, and the influence decreased successively, while the influence was negatively correlated with the axial length of the friction cone, which had the least influence. Through the optimized design, the peak force of the shrink tube increased by only 5.41%, while the specific energy absorption increased by 31.03%. Additionally, the mean force was closer to the technical requirements of 600 kN, and the crashworthiness was optimized. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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36 pages, 11422 KiB

Open AccessArticle

Analysis and Experiment of Thermal Field Distribution and Thermal Deformation of Nut Rotary Ball Screw Transmission Mechanism

by Hanwen Yu, Xuecheng Luan, Guiyuan Zheng, Guangchao Hao, Yan Liu, Hongyu Xing, Yandong Liu, Xiaokui Fu and Zhi Liu

Appl. Sci. 2024, 14(13), 5790; https://doi.org/10.3390/app14135790 - 2 Jul 2024

Cited by 1 | Viewed by 1349

Abstract

This study designs a differential dual-drive micro-feed mechanism, superposing the two “macro feed motions” (“motor drive screw” and “motor drive nut”) using the same transmission of “the nut rotary ball screw pair” structure. These two motions are almost equal in terms of speed [...] Read more.

This study designs a differential dual-drive micro-feed mechanism, superposing the two “macro feed motions” (“motor drive screw” and “motor drive nut”) using the same transmission of “the nut rotary ball screw pair” structure. These two motions are almost equal in terms of speed and turning direction, thus the “micro feed” can be obtained. (1) Background: Thermal deformation is the primary factor that can restrict the high-precision micro-feed mechanism and the distribution of heat sources differs from that of the conventional screw single-drive system owing to the structure and motion features of the transmission components. (2) Discussion: This study explores the thermal field distribution and thermal deformation of the differentially driven micro-feed mechanism when two driving motors are combined at different speeds. (3) Methods: Based on the theory of heat transfer, the differential dual-drive system can be used as the research object. The thermal equilibrium equations of the micro-feed transmission system are established using the thermal resistance network method, and a thermal field distribution model is obtained. (4) Results: Combined with the mechanism of thermal deformation theory, the established thermal field model is used to predict the axial thermal deformation of the differential dual-drive ball screw. (5) Conclusions: Under the dual-drive condition, the steady-state thermal error of the nut-rotating ball screw transmission mechanism increases with the increase in nut speed and composite speed and is greater than the steady-state thermal error under the single screw drive condition. After reaching the thermal steady state, the measured thermal elongation at the end of the screw in the experiment is approximately 10.5 μm and the simulation result is 11.98 μm. The experimental measurement result demonstrates the accuracy of the theoretical analysis model for thermal error at the end of the screw. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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18 pages, 9022 KiB

Open AccessArticle

Influence of Materials of Moulds and Geometry of Specimens on Mechanical Properties of Grouts Based on Ultrafine Hydraulic Binder

by Beatriz Hortigon, Esperanza Rodriguez-Mayorga, Jose Antonio Santiago-Espinal, Fernando Ancio and Jose Maria Gallardo

Materials 2024, 17(7), 1645; https://doi.org/10.3390/ma17071645 - 3 Apr 2024

Cited by 2 | Viewed by 1035

Abstract

Ultrafine hydraulic binder grout injection is a technique utilised for repairing masonry, either to connect sections, seal joints, or fill voids due to its great capacity for penetration and higher mechanical strength than lime grout. In this research, the mechanical properties of ultrafine [...] Read more.

Ultrafine hydraulic binder grout injection is a technique utilised for repairing masonry, either to connect sections, seal joints, or fill voids due to its great capacity for penetration and higher mechanical strength than lime grout. In this research, the mechanical properties of ultrafine hydraulic cement grout are analysed considering the influence of the mould material for preparing the specimens and their geometry characteristics in the context of the specifications set out in several international standards. The test campaign to ascertain compressive and flexural strength in different circumstances is supplemented with a physical and chemical characterisation of both binder and fresh and hardened grout. Significant differences in mechanical properties between specimens prepared with absorbent or non-absorbent-water material are found due to the influence of drying shrinkage and decanting binder during the curing process. Furthermore, the slenderness of specimens is presented as an important factor in determining the compressive strength of mixtures. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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14 pages, 10482 KiB

Open AccessArticle

Effect of the Silanization of Aerosil OX50 in the Properties of Light-Cured Dental Composites

by Selena de la Caridad Díaz-Rodríguez, Oridayma Tarano-Artigas, Wilberth Herrera-Kao, Juan Valerio Cauich-Rodríguez, José Manuel Cervantes-Uc, Ana Rosa-Sainz, Amisel Almirall La Serna and Yaymarilis Veranes-Pantoja

Appl. Sci. 2024, 14(6), 2453; https://doi.org/10.3390/app14062453 - 14 Mar 2024

Cited by 2 | Viewed by 1733

Abstract

In this study, the surface of aerosil OX50 was treated with γ-methacryloxypropyltrimethoxysilane in order to evaluate its effect on light-cured dental composites. Four composites were prepared with Bis-GMA/tetraethylene glycol dimethacrylate/γ-methacryloxypropyltrimethoxysilane, Bis-GMA/tetraethylene glycol dimethacrylate, and a 45% treated or untreated aerosil OX50, using the [...] Read more.

In this study, the surface of aerosil OX50 was treated with γ-methacryloxypropyltrimethoxysilane in order to evaluate its effect on light-cured dental composites. Four composites were prepared with Bis-GMA/tetraethylene glycol dimethacrylate/γ-methacryloxypropyltrimethoxysilane, Bis-GMA/tetraethylene glycol dimethacrylate, and a 45% treated or untreated aerosil OX50, using the camphorquinone/N,N-dimethylaminoethyl methacrylate pair as initiator. Evidence of filler silanization was provided by FTIR as a low-intensity absorption at 1707 cm⁻¹ (carbonyl functional group) while thermogravimetric analysis showed a mass loss of approximately 2% associated with the decomposition of γ-methacryloxypropyltrimethoxysilane. The experimental composites studied meet the requirements of the ISO 4049:2019 standard for depth of cure, water sorption, and solubility. The composites are shown to be thermally stable and presented a degree of conversion higher than 70%, being higher than that reported for many commercial composites. Based on the observed properties, the best formulations were those in which the silane is incorporated into the matrix and the filler was previously treated. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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15 pages, 4946 KiB

Open AccessArticle

Feasibility of Invasive Brown Seaweed Rugulopteryx okamurae as Source of Alginate: Characterization of Products and Evaluation of Derived Gels

by Ismael Santana, Manuel Felix and Carlos Bengoechea

Polymers 2024, 16(5), 702; https://doi.org/10.3390/polym16050702 - 5 Mar 2024

Cited by 5 | Viewed by 1704

Abstract

Rugulopteryx okamurae (RO) is an invasive brown seaweed that causes severe environmental problems in the Mediterranean Sea. This work proposed an extraction method that enables their use as a raw material for producing sodium alginate. Alginate was successfully extracted from this invasive seaweed, [...] Read more.

Rugulopteryx okamurae (RO) is an invasive brown seaweed that causes severe environmental problems in the Mediterranean Sea. This work proposed an extraction method that enables their use as a raw material for producing sodium alginate. Alginate was successfully extracted from this invasive seaweed, with its gelling performance in the presence of Ca²⁺ ions comparable to existing commercial alginates. The mannuronic acid (M)-to-guluronic (G) acid ratio in the ¹H-NMR profile indicated a higher percentage of G in the RO-extracted alginate, which implies a greater formation of so-called egg box structures. These differences resulted in their different rheological behaviour, as sodium alginate aqueous solutions exhibited a greater viscosity (

η

at 1 s⁻¹ = 3.8 ± 0.052 Pa·s) than commercial alginate (2.8 ± 0.024 Pa·s), which is related to the egg box structure developed. When gelled in the presence of calcium, an increase in the value of the elastic modulus was observed. However, the value of the tan δ for the extracted alginate was lower than that of commercial alginate gels, confirming a structure more densely packed, which implies a different restructuring of the alginate chain when gelling. These results confirm the suitability of using invasive Rugulopteryx okamurae as a source of calcium alginate gels. In this way, sustainable bio-based materials may be produced from undesired biomass that currently poses a threat to the ecosystem. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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15 pages, 16171 KiB

Open AccessArticle

Protecting FPGA-Based Cryptohardware Implementations from Fault Attacks Using ADCs

by Francisco Eugenio Potestad-Ordóñez, Alejandro Casado-Galán and Erica Tena-Sánchez

Sensors 2024, 24(5), 1598; https://doi.org/10.3390/s24051598 - 29 Feb 2024

Cited by 2 | Viewed by 1700

Abstract

The majority of data exchanged between connected devices are confidential and must be protected against unauthorized access. To ensure data protection, so-called cryptographic algorithms are used. These algorithms have proven to be mathematically secure against brute force due to the key length, but [...] Read more.

The majority of data exchanged between connected devices are confidential and must be protected against unauthorized access. To ensure data protection, so-called cryptographic algorithms are used. These algorithms have proven to be mathematically secure against brute force due to the key length, but their physical implementations are vulnerable against physical attacks. The physical implementation of these algorithms can result in the disclosure of information that can be used to access confidential data. Some of the most powerful hardware attacks presented in the literature are called fault injection attacks. These attacks involve introducing a malfunction into the normal operation of the device and then analyzing the data obtained by comparing them with the expected behavior. Some of the most common methods for injecting faults are the variation of the supply voltage and temperature or the injection of electromagnetic pulses. In this paper, a hardware design methodology using analog-to-digital converters (ADCs) is presented to detect attacks on cryptocircuits and prevent information leakage during fault injection attacks. To assess the effectiveness of the proposed design approach, FPGA-based ADC modules were designed that detect changes in temperature and supply voltage. Two setups were implemented to test the scheme against voltage and temperature variations and injections of electromagnetic pulses. The results obtained demonstrate that, in 100% of the cases, when the correct operating voltage and temperature range were established, the detectors could activate an alarm signal when the cryptographic module was attacked, thus avoiding confidential information leakage and protecting data from being exploited. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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13 pages, 1911 KiB

Open AccessArticle

Chloride Permeability of Alkali-Activated Slag Concretes after Exposure to High Temperatures

by Baomeng Zhou, Qianmin Ma, Rongxin Guo and Ping Li

Materials 2024, 17(5), 1028; https://doi.org/10.3390/ma17051028 - 23 Feb 2024

Cited by 1 | Viewed by 1051

Abstract

The number of fires in buildings and on bridges has increased worldwide in recent years. As a structural material, the strength of alkali-activated slag (AAS) concrete after exposure to high temperatures has been given much attention. However, research of its durability is still [...] Read more.

The number of fires in buildings and on bridges has increased worldwide in recent years. As a structural material, the strength of alkali-activated slag (AAS) concrete after exposure to high temperatures has been given much attention. However, research of its durability is still lacking, which limits the application of this type of concrete on a larger scale. In this context, as one of the most important aspects of durability, the chloride permeability of AAS concretes after exposure to high temperatures was examined in this study. The influence of the alkali concentration (Na₂O%) and the modulus (Ms) of the activator, as well as the influence of heating regimes, including the heating rate, duration of exposure to the target temperature, and cooling method, was also discussed. The results show that the chloride permeability of the AAS concretes increased with temperature elevation. Due to the interference of pore solution conductivity, the influence of the Na₂O% and the Ms of the activator on the chloride permeability of the AAS concretes was not made clear by using the ASTM C 1202 charge passed method; however, after exposure to high temperatures, AAS with a lower Na₂O% and lower Ms has lower porosity and may have lower chloride permeability, which needs further investigation. Faster heating for a longer duration at the target temperature and water cooling reduced the resistance of the AAS concretes to chloride permeability as a result of their increased porosity. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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17 pages, 4497 KiB

Open AccessArticle

Identification of Olives Using In-Field Hyperspectral Imaging with Lightweight Models

by Samuel Domínguez-Cid, Diego Francisco Larios, Julio Barbancho, Francisco Javier Molina, Javier Antonio Guerra and Carlos León

Sensors 2024, 24(5), 1370; https://doi.org/10.3390/s24051370 - 20 Feb 2024

Cited by 1 | Viewed by 1487

Abstract

During the growing season, olives progress through nine different phenological stages, starting with bud development and ending with senescence. During their lifespan, olives undergo changes in their external color and chemical properties. To tackle these properties, we used hyperspectral imaging during the growing [...] Read more.

During the growing season, olives progress through nine different phenological stages, starting with bud development and ending with senescence. During their lifespan, olives undergo changes in their external color and chemical properties. To tackle these properties, we used hyperspectral imaging during the growing season of the olives. The objective of this study was to develop a lightweight model capable of identifying olives in the hyperspectral images using their spectral information. To achieve this goal, we utilized the hyperspectral imaging of olives while they were still on the tree and conducted this process throughout the entire growing season directly in the field without artificial light sources. The images were taken on-site every week from 9:00 to 11:00 a.m. UTC to avoid light saturation and glitters. The data were analyzed using training and testing classifiers, including Decision Tree, Logistic Regression, Random Forest, and Support Vector Machine on labeled datasets. The Logistic Regression model showed the best balance between classification success rate, size, and inference time, achieving a 98% F1-score with less than 1 KB in parameters. A reduction in size was achieved by analyzing the wavelengths that were critical in the decision making, reducing the dimensionality of the hypercube. So, with this novel model, olives in a hyperspectral image can be identified during the season, providing data to enhance a farmer’s decision-making process through further automatic applications. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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18 pages, 4532 KiB

Open AccessArticle

Development and Characterization of Edible Films Based on Cassava Starch Modified by Corona Treatment

by Carlos Mauricio Otálora González, Manuel Felix, Carlos Bengoechea, Silvia Flores and Lía Noemí Gerschenson

Foods 2024, 13(3), 468; https://doi.org/10.3390/foods13030468 - 2 Feb 2024

Cited by 7 | Viewed by 2064

Abstract

Corona treatment (CT), a surface treatment widely used in the plastic industry, can be used to alter the properties of cassava starch. In the present work, CT was performed on dry granular starch (DS), water-suspended humid granular starch (HS), and gelatinized starch (GS). [...] Read more.

Corona treatment (CT), a surface treatment widely used in the plastic industry, can be used to alter the properties of cassava starch. In the present work, CT was performed on dry granular starch (DS), water-suspended humid granular starch (HS), and gelatinized starch (GS). Different properties and structural characteristics of treated starches were studied. A lowering in pH was generally observed after CT and the rheological properties depended on the starch presentation. A reinforcement of DS and HS samples after CT was deduced from higher viscosity values in flow assays and viscoelastic moduli, but weak gels were obtained when CT was applied to GS. Changes in the A-type polymorphic structure, as well as a drop in relative crystallinity, were produced by CT for DS and HS. Additionally, changes in O-H and C-O-C FTIR bands were observed. Therefore, CT can be applied for starch modification, producing predominantly cross-linking in the DS and de-polymerization in the HS. Casting films made from the modified DS showed higher tensile strength and lower hydrophilicity, solubility, water absorption capacity, and water vapor permeability. Thus, the DS cross-linking induced by CT improved mechanical characteristics and hydrophobicity in edible films, which can be better used as packaging materials. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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21 pages, 10097 KiB

Open AccessArticle

Assessing Formability and Failure of UHMWPE Sheets through SPIF: A Case Study in Medical Applications

by Ana Rosa-Sainz, M. Beatriz Silva, Ana M. Beltrán, Gabriel Centeno and Carpóforo Vallellano

Polymers 2023, 15(17), 3560; https://doi.org/10.3390/polym15173560 - 27 Aug 2023

Cited by 3 | Viewed by 1810

Abstract

This work presents a comprehensive investigation of an experimental study conducted on ultra-high molecular weight polyethylene (UHMWPE) sheets using single point incremental forming (SPIF). The analysis is performed within a previously established research framework to evaluate formability and failure characteristics, including necking and [...] Read more.

This work presents a comprehensive investigation of an experimental study conducted on ultra-high molecular weight polyethylene (UHMWPE) sheets using single point incremental forming (SPIF). The analysis is performed within a previously established research framework to evaluate formability and failure characteristics, including necking and fracture, in both conventional Nakajima tests and incremental sheet forming specimens. The experimental design of the SPIF tests incorporates process parameters such as spindle speed and step down to assess their impact on the formability of the material and the corresponding failure modes. The results indicate that a higher step down value has a positive effect on formability in the SPIF context. The study has identified the tool trajectory in SPIF as the primary influencing factor in the twisting failure mode. Implementing a bidirectional tool trajectory effectively reduced instances of twisting. Additionally, this work explores a medical case study that examines the manufacturing of a polyethylene liner device for a total hip replacement. This investigation critically analyses the manufacturing of plastic liner using SPIF, focusing on its formability and the elastic recovery exhibited by the material. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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17 pages, 26105 KiB

Open AccessArticle

Mechanical Properties of Weld Lines in Injection-Molded Carbon Fiber-Reinforced Nylon (PA-CF) Composites

by Xianpeng Wang, Zuguo Bao, Donglin Gao, Shiyao Huang, Li Huang, Qiuren Chen, Hailong Zhao, Weijian Han and Yahong Xu

Polymers 2023, 15(11), 2476; https://doi.org/10.3390/polym15112476 - 27 May 2023

Cited by 3 | Viewed by 2456

Abstract

Weld lines are a common defect generated in injection molding, which apparently affects the performance of final products, but the available reports on carbon fiber-reinforced thermoplastics are still rather few. In this study, the effects of injection temperature, injection pressure, and fiber content [...] Read more.

Weld lines are a common defect generated in injection molding, which apparently affects the performance of final products, but the available reports on carbon fiber-reinforced thermoplastics are still rather few. In this study, the effects of injection temperature, injection pressure, and fiber content on the mechanical properties of weld lines were studied for carbon fiber-reinforced nylon (PA-CF) composites. The weld line coefficient was also calculated by comparing specimens with and without weld lines. The tensile and flexural properties of PA-CF composites significantly increased with the rise of fiber content for specimens without weld lines, while injection temperature and pressure demonstrated slight influences on mechanical properties. However, the existence of weld lines had negative influences on the mechanical properties of PA-CF composites due to poor fiber orientation in weld line regions. The weld line coefficient of PA-CF composites decreased as fiber content increased, indicating that the damage of weld lines to mechanical properties increased. The microstructure analysis showed that there were a large number of fibers distributed vertically to flow direction in weld lines regions, which could not play a reinforcing role. In addition, increasing injection temperature and pressure facilitated fiber orientation, which improved the mechanical properties of composites with low fiber content, while weakening composites with high fiber content instead. This article provides practical information for product design containing weld lines, which helps to optimize the forming process and formula design of PA-CF composites with weld lines. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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12 pages, 3482 KiB

Open AccessArticle

Effect of pH Hydrolysis on the Recovery of Antimony from Spent Electrolytes from Copper Production

by Eduardo Díaz Gutiérrez, José Antonio Maldonado Calvo, José María Gallardo Fuentes and Antonio Paúl Escolano

Materials 2023, 16(11), 3918; https://doi.org/10.3390/ma16113918 - 23 May 2023

Cited by 4 | Viewed by 1349

Abstract

This study examined how pH hydrolysis affects the recovery process for antimony extracted from spent electrolytes. Various OH⁻ reagents were used to adjust the pH levels. The findings reveal that pH plays a crucial role in determining the optimal conditions for extracting [...] Read more.

This study examined how pH hydrolysis affects the recovery process for antimony extracted from spent electrolytes. Various OH⁻ reagents were used to adjust the pH levels. The findings reveal that pH plays a crucial role in determining the optimal conditions for extracting antimony. The results show that NH₄OH and NaOH are more effective compared to water, with optimal conditions at pH 0.5 for water and pH 1 for NH₄OH and NaOH, resulting in average antimony extraction yields of 90.4%, 96.1%, and 96.7%, respectively. Furthermore, this approach helps to improve both crystallography and purity related to recovered antimony samples obtained through recycling processes. The solid precipitates obtained lack a crystalline structure, making it difficult to identify the compounds formed, but element concentrations suggest the presence of oxychloride or oxide compounds. Arsenic is incorporated into all solids, affecting the purity of the product, and water showing higher antimony content (68.38%) and lower arsenic values (8%) compared to NaOH and NH₄OH. Bismuth integration into solids is less than arsenic (less than 2%) and remains unaffected by pH levels except in tests with water, where a bismuth hydrolysis product is identified at pH 1, accounting for the observed reduction in antimony extraction yields. Full article

(This article belongs to the Topic Scientific Advances in STEM: Synergies to Achieve Success, 3rd Volume)

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