Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
5.1
2.8
Journals
Processes
Special Issues
Features, Reviews and Perspectives for the 10th Anniversary of Processes
share announcement

Features, Reviews and Perspectives for the 10th Anniversary of Processes

A special issue of Processes (ISSN 2227-9717). This special issue belongs to the section "Advanced Digital and Other Processes".

Deadline for manuscript submissions: 31 December 2024 | Viewed by 60153

Special Issue Editors

Prof. Dr. Giancarlo Cravotto

E-Mail Website
Guest Editor
Department of Drug Science and Technology, University of Turin, Via P. Giuria 9, 10125 Turin, Italy
Interests: green chemistry; process intensification; green extraction; enabling technologies (ultrasound, microwaves, hydrodynamic cavitation, ball milling, flow chemistry); sustainable chemical processes
Special Issues, Collections and Topics in MDPI journals
Prof. Dr. Zhen Fang

E-Mail Website
Guest Editor
College of Engineering, Nanjing Agricultural University, A503 YuXian Building, 40 Dianjiangtai Road, Nanjing 210031, China
Interests: biofuels; biomass; supercritical water; biodiesel
Dr. Jose V. Garcia-Perez

E-Mail Website
Guest Editor
Department of Food Technology, Universitat Politècnica de València, Valencia, Spain
Interests: high power ultrasound; pulsed electric fields-PEF; moderate electric fields-MEF; supercritical fluids; drying; extraction; heat transfer; modeling; non-destructive ultrasonic testing; texture
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

As Processes editors, authors, reviewers, and readers, we have the opportunity to celebrate the 10th anniversary of the journal with a Special Issue. Our goal is to highlight the advances and achievements of the past few years. In various fields, new technologies, augmented reality, artificial intelligence, and machine learning could revolutionise the traditional methods and protocols. The current transdisciplinary approach to design highly efficient and sustainable processes will open up new scenarios with major implications for industrial production, research laboratories and society.

I expect that the special issue "Features, Reviews and Perspectives for the 10th Anniversary of Processes" will redraw the scientific and technical skyline of the third millennium.

Prof. Dr. Giancarlo Cravotto
Prof. Dr. Zhen Fang
Prof. Dr. Jose V. Garcia-Perez
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Processes is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (29 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

Jump to: Review

15 pages, 5888 KiB  
Article
Simulation and Experiment on Hull Lower Welding Deformation Using Heat Source Shape
by Chung-Woo Lee, Suseong Woo and Jisun Kim
Processes 2024, 12(12), 2628; https://doi.org/10.3390/pr12122628 - 22 Nov 2024
Abstract
To effectively use aluminum, which is inherently weak under heat, as a material for hull construction, it is crucial to precisely predict the thermal deformation in the weld zone. Most studies employing finite element (FE) methods to predict thermal deformation due to welding [...] Read more.
To effectively use aluminum, which is inherently weak under heat, as a material for hull construction, it is crucial to precisely predict the thermal deformation in the weld zone. Most studies employing finite element (FE) methods to predict thermal deformation due to welding typically use estimated heat source conditions based on the results of the weld. However, these estimated values can differ significantly from the actual welding conditions. In this study, we investigated whether using the actual shape of the heat source, rather than an estimated value, can serve as a reliable condition for analysis in predicting thermal deformation. This prediction is essential for minimizing deformation in the fillet welds of an aluminum hull. To compare deformation outcomes, Al 5083, commonly used in hull construction, was selected as the base material. The thermal deformation of aluminum hull fillet welds, welded using the Cold Metal Transfer (CMT) welding method, which reduces heat input, was measured. The simulation results demonstrated similar deformation trends, with discrepancies ranging from a minimum of 0.02 mm to a maximum of 1.4 mm when using actual welding conditions and heat source shapes. The results of this study confirm that the actual heat source shape can be utilized as a reliable condition for predicting thermal deformation in aluminum hull welds. The aim is to contribute to the improvement of aluminum hull manufacturing quality by providing essential data for establishing welding conditions and minimizing deformation. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

11 pages, 19447 KiB  
Article
Microstructure Characteristics and Elevated-Temperature Wear Mechanism of FeCoCrNiAl High-Entropy Alloy Prepared by Laser Cladding
by Yali Gao, Sicheng Bai, Guangpeng Kou, Shan Jiang, Yu Liu and Dongdong Zhang
Processes 2024, 12(10), 2228; https://doi.org/10.3390/pr12102228 - 13 Oct 2024
Viewed by 823
Abstract
This paper investigated the FeCoCrNiAl high-entropy alloy on H13 steel, prepared using laser cladding, to improve the elevated-temperature wear resistance of the alloy. The results revealed that FCC and BCC phases, in terms of the coating, produced a large dislocation density. The coating [...] Read more.
This paper investigated the FeCoCrNiAl high-entropy alloy on H13 steel, prepared using laser cladding, to improve the elevated-temperature wear resistance of the alloy. The results revealed that FCC and BCC phases, in terms of the coating, produced a large dislocation density. The coating exhibited a columnar and equiaxed crystal microstructure. With the comprehensive effects of fine-grain strengthening, solid solution strengthening, and dislocation strengthening, the average hardness of the coating (500 HV0.1) was improved by 150% compared with that of H13 steel (200 HV0.1). The wear experiments were conducted at 623 K, 723 K, and 823 K. Compared with H13 steel, the wear volume of the coating decreased by 59.20%, 70.79%, and 78.20% under different temperatures. The wear forms impacting the coating were mainly abrasive wear and oxidation wear. However, H13 steel presented adhesive wear and fatigue wear, in addition to abrasive wear and oxidation wear. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

19 pages, 3810 KiB  
Article
Advanced Processes in Water Treatment: Synergistic Effects of Hydrodynamic Cavitation and Cold Plasma on Rhodamine B Dye Degradation
by Federico Verdini, Daniele Crudo, Valentina Bosco, Anna V. Kamler, Giancarlo Cravotto and Emanuela Calcio Gaudino
Processes 2024, 12(10), 2128; https://doi.org/10.3390/pr12102128 - 30 Sep 2024
Viewed by 843
Abstract
The increasing pollution of water bodies, due to the constant release of highly toxic and non-biodegradable organic pollutants, requires innovative solutions for environmental remediation and wastewater treatment. In this study, the effectiveness of different Advanced Oxidation Processes (AOPs) for the purification of water [...] Read more.
The increasing pollution of water bodies, due to the constant release of highly toxic and non-biodegradable organic pollutants, requires innovative solutions for environmental remediation and wastewater treatment. In this study, the effectiveness of different Advanced Oxidation Processes (AOPs) for the purification of water contaminated with Rhodamine B (RhB) dye at a concentration of 5 mg/L were investigated and compared. Using the classical ozonation strategy as a benchmark treatment, the research showed over 99% degradation of RhB within 4 min in a laboratory-scale batch setup with a capacity of 0.2 L. In contrast, a “chemical-free” process exploiting ultrasound (US) technology achieved a 72% degradation rate within 60 min. Further experiments were conducted using a pilot-scale rotor-stator hydrodynamic cavitation (HC) reactor on a 15 L solution leading to 33% of RhB removal in the presence of hydrogen peroxide (H2O2) at 75 mg/L. However, the use of an innovative cavitational reactor, which hybridizes HC with cold plasma, showed remarkable efficiency and achieved 97% degradation of RhB in just 5 min when treating a 5 L solution at an inlet pressure of 20 bar in a loop configuration. In addition, a degradation rate of 58% was observed in a flow-through configuration, emphasising the robustness and scalability of the HC/electrical discharge (ED) plasma technology. These results underline the potential of hybrid HC/ED plasma technology as an intensified and scalable process for the purification of water, as it offers a catalyst- and oxidant-free protocol. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

17 pages, 1926 KiB  
Article
Influence of Plasticizers Concentration on Thermal, Mechanical, and Physicochemical Properties on Starch Films
by Elena-Emilia Sirbu, Alin Dinita, Maria Tănase, Alexandra-Ileana Portoacă, Andreea Bondarev, Cristina-Emanuela Enascuta and Catalina Calin
Processes 2024, 12(9), 2021; https://doi.org/10.3390/pr12092021 - 19 Sep 2024
Viewed by 782
Abstract
The increasing demand for sustainable packaging materials has driven the exploration of biodegradable alternatives to synthetic plastics. This study investigates the thermal and mechanical properties of starch-based films plasticized with varying concentrations of glycerol and sorbitol. Cornstarch films were prepared with glycerol and [...] Read more.
The increasing demand for sustainable packaging materials has driven the exploration of biodegradable alternatives to synthetic plastics. This study investigates the thermal and mechanical properties of starch-based films plasticized with varying concentrations of glycerol and sorbitol. Cornstarch films were prepared with glycerol and sorbitol plasticizers in different ratios, and their physical characteristics, including swelling index, water solubility, and thermal stability, were assessed using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and tensile testing. The results indicate that the incorporation of plasticizers significantly influenced the films’ properties. Films with higher glycerol content exhibited greater flexibility and solubility, while sorbitol-plasticized films showed enhanced thermal stability. The combination of both plasticizers yielded films with balanced properties suitable for food packaging applications. This study demonstrates the potential of glycerol and sorbitol as effective plasticizers in developing biodegradable starch-based films, offering a promising alternative to conventional plastic packaging. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

17 pages, 7451 KiB  
Article
Prediction of Air Purifier Effectiveness for Eliminating Exhaled Droplets in a Confined Room
by Yumeng Zhao, Alexander Russell, Kingsly Ambrose and Carl R. Wassgren
Processes 2024, 12(9), 1917; https://doi.org/10.3390/pr12091917 - 6 Sep 2024
Cited by 1 | Viewed by 817
Abstract
High-efficiency particulate air (HEPA) filter purifiers are a recommended method for eliminating respiratory airborne droplets. In this study, the movement of airborne droplets exhaled by occupants in an unventilated, two-bed dormitory room with an air purifier was simulated using computational fluid dynamics. The [...] Read more.
High-efficiency particulate air (HEPA) filter purifiers are a recommended method for eliminating respiratory airborne droplets. In this study, the movement of airborne droplets exhaled by occupants in an unventilated, two-bed dormitory room with an air purifier was simulated using computational fluid dynamics. The air was modeled using an Eulerian scheme while the droplets were modeled using a Lagrangian method. The airborne droplet number, the rate at which droplets are removed, and the rate at which droplets accumulate were calculated. A larger HEPA flow rate increased the droplet removal efficiency, with most of the droplets settling on boundary surfaces. Of particular note, the air purifier location within the room had a significant impact on reducing the droplet exchange between two occupants and improving the droplet elimination efficiency. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

20 pages, 7618 KiB  
Article
A Novel CEM-Based 2-DOF PID Controller for Low-Pressure Turbine Speed Control of Marine Gas Turbine Engines
by Gun-Baek So
Processes 2024, 12(9), 1916; https://doi.org/10.3390/pr12091916 - 6 Sep 2024
Viewed by 663
Abstract
Gas turbine engines have several advantages over piston reciprocating engines, such as higher output per unit volume, reduced vibration, rapid acceleration and deceleration, high power output, and clean exhaust gases. As a result, their use for propulsion in ships has been steadily increasing. [...] Read more.
Gas turbine engines have several advantages over piston reciprocating engines, such as higher output per unit volume, reduced vibration, rapid acceleration and deceleration, high power output, and clean exhaust gases. As a result, their use for propulsion in ships has been steadily increasing. However, gas turbine engines exhibit significant parameter variations depending on the rotational speed, making the design of controllers to ensure system stability while achieving satisfactory control performance, a very challenging task. In this paper, a novel CEM-based 2-DOF PID controller design technique is proposed to ensure the stability of a gas turbine engine while improving tracking and disturbance rejection performance. The proposed controller consists of a PID controller focused on enhancing disturbance rejection performance and a set-point filter to improve tracking performance. The set-point filter is composed of gains from the controller and a single weighting factor. When tuning the gains of the controller, the maximum sensitivity is considered to maintain an appropriate balance between system stability and response performance. The key novelty of this study can be summarized in two main points. One is that the controller is designed by matching characteristic equations, and by setting the roots of the desired characteristic equation as multipoles, the gains of the PID controller can be tuned with only one adjusting variable, making the tuning of the 2-DOF controller easier. The other is that the controller parameters are tuned based on maximum sensitivity, thus taking into account the robust stability of the control system. To demonstrate the feasibility of the proposed method, simulations are conducted for four scenarios using various performance indices. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

17 pages, 3280 KiB  
Article
Co-Gasification of Plastic Waste Blended with Biomass: Process Modeling and Multi-Objective Optimization
by Tanawat Aentung, Yaneeporn Patcharavorachot and Wei Wu
Processes 2024, 12(9), 1906; https://doi.org/10.3390/pr12091906 - 5 Sep 2024
Viewed by 1081
Abstract
Mixed plastic/biomass co-gasification stands out as a promising and environmentally friendly technology, since it reduces wide solid wastes and produces green hydrogen. High-quality syngas can be obtained by virtue of the process design and optimization of a downdraft fixed-bed co-gasifier. The design is [...] Read more.
Mixed plastic/biomass co-gasification stands out as a promising and environmentally friendly technology, since it reduces wide solid wastes and produces green hydrogen. High-quality syngas can be obtained by virtue of the process design and optimization of a downdraft fixed-bed co-gasifier. The design is based on the actual reaction zones within a real gasifier to ensure accurate results. The methodology shows that (i) the co-gasifier modeling is validated using the adiabatic RGibbs model in Aspen Plus, (ii) the performance of the co-gasifier is evaluated using cold-gas efficiency (CGE) and carbon conversion efficiency (CCE) as indicators, and (iii) the multi-objective optimization (MOO) is employed to optimize these indicators simultaneously, utilizing a standard genetic algorithm (GA) combined with response surface methodology (RSM) to identify the Pareto frontier. The optimal conditions, resulting in a CGE of 91.78% and a CCE of 83.77% at a gasifier temperature of 967.89 °C, a steam-to-feed ratio of 1.40, and a plastic-to-biomass ratio of 74.23%, were identified using the technique for order of preference by similarity to ideal solution (TOPSIS). The inclusion of plastics enhances gasifier performance and syngas quality, leading to significant improvements in CGE and CCE values. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

15 pages, 3059 KiB  
Article
Preliminary Exploration of Low Frequency Low-Pressure Capacitively Coupled Ar-O2 Plasma
by Niaz Wali, Weiwen Xiao, Qayam Ud Din, Najeeb Ur Rehman, Chiyu Wang, Jiatong Ma, Wenjie Zhong and Qiwei Yang
Processes 2024, 12(9), 1858; https://doi.org/10.3390/pr12091858 - 31 Aug 2024
Viewed by 1001
Abstract
Non-thermal plasma as an emergent technology has received considerable attention for its wide range of applications in agriculture, material synthesis, and the biomedical field due to its low cost and portability. It has promising antimicrobial properties, making it a powerful tool for bacterial [...] Read more.
Non-thermal plasma as an emergent technology has received considerable attention for its wide range of applications in agriculture, material synthesis, and the biomedical field due to its low cost and portability. It has promising antimicrobial properties, making it a powerful tool for bacterial decontamination. However, traditional techniques for producing non-thermal plasma frequently rely on radiofrequency (RF) devices, despite their effectiveness, are intricate and expensive. This study focuses on generating Ar-O2 capacitively coupled plasma under vacuum conditions, utilizing a low-frequency alternating current (AC) power supply, to evaluate the system’s antimicrobial efficacy. A single Langmuir probe diagnostic was used to assess the key plasma parameters such as electron density (ne), electron temperature (Te), and electron energy distribution function (EEDF). Experimental results showed that ne increases (7 × 1015 m−3 to 1.5 × 1016 m−3) with a rise in pressure and AC power. Similarly, the EEDF modified into a bi-Maxwellian distribution with an increase in AC power, showing a higher population of low-energy electrons at higher power. Finally, the generated plasma was tested for antimicrobial treatment of Xanthomonas campestris pv. Vesicatoria. It is noted that the plasma generated by the AC power supply, at a pressure of 0.5 mbar and power of 400 W for 180 s, has 75% killing efficiency. This promising result highlights the capability of the suggested approach, which may be a budget-friendly and effective technique for eliminating microbes with promising applications in agriculture, biomedicine, and food processing. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

18 pages, 10439 KiB  
Article
Experimental Study of the Characteristics of HI Distillation in the Thermochemical Iodine–Sulfur Cycle for Hydrogen Production
by Jinxu Zhang, Bo Ling, Yong He, Yanqun Zhu and Zhihua Wang
Processes 2024, 12(8), 1768; https://doi.org/10.3390/pr12081768 - 21 Aug 2024
Cited by 1 | Viewed by 678
Abstract
Hydrogen energy, as a clean, renewable, and high-calorific energy carrier, has garnered significant attention globally. Among various hydrogen production methods, the thermochemical iodine–sulfur (I-S) cycle is considered the most promising due to its high efficiency and adaptability for large-scale industrial applications. This study [...] Read more.
Hydrogen energy, as a clean, renewable, and high-calorific energy carrier, has garnered significant attention globally. Among various hydrogen production methods, the thermochemical iodine–sulfur (I-S) cycle is considered the most promising due to its high efficiency and adaptability for large-scale industrial applications. This study focuses on the distillation characteristics of the HIx (HI–I2–H2O) solution within the I-S cycle, which is crucial for achieving the high-concentration HI necessary for efficient hydrogen production. Previous methods, including phosphoric acid extraction–distillation and reactive distillation, have addressed azeotrope issues but introduced complexities and equipment demands. This research constructs a hypo-azeotropic HIx solution distillation experimental system and uses the Aspen Plus v14 software to optimize distillation parameters. By analyzing the effects of feed stage, reflux ratio, and feed temperature, the study provides essential data for improving distillation efficiency and supports the scale-up of I-S cycle technology. The findings indicate that optimal distillation is achieved with a feed position at 1/3 column height, a reflux ratio of 1.4, and a feed temperature near the boiling point, enhancing the feasibility of industrial hydrogen production via the I-S cycle. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

21 pages, 8744 KiB  
Article
Green Synthesis of Yttrium Derivatives Nanoparticles Using Pine Needle Leaf Extract: Characterization, Docking, Antibacterial, and Antioxidant Potencies
by Nourhane A. Darwich, Malak Mezher, Alaa M. Abdallah, Ahmed F. El-Sayed, Rana El Hajj, Taymour A. Hamdalla and Mahmoud I. Khalil
Processes 2024, 12(8), 1713; https://doi.org/10.3390/pr12081713 - 15 Aug 2024
Viewed by 1017
Abstract
Green nanoparticles are synthesized using environmentally friendly methods, and natural materials hold significant importance. This makes the process environmentally sustainable and reduces the production of harmful waste by-products. Green nanoparticles exhibit reduced toxicity which is crucial for biomedical applications. The current study suggested [...] Read more.
Green nanoparticles are synthesized using environmentally friendly methods, and natural materials hold significant importance. This makes the process environmentally sustainable and reduces the production of harmful waste by-products. Green nanoparticles exhibit reduced toxicity which is crucial for biomedical applications. The current study suggested that yttrium nanoparticles (YNPs) should be synthesized, characterized, and evaluated for their diverse biological applications due to the rise in antibacterial resistance. The YNPs were prepared using a pine needle leaf extract (PNLE). The structural and morphological features have been investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–vis), and vibrating sample magnetometry (VSM). The XRD pattern demonstrated the presence of yttrium oxide and yttrium nitrate phases. The crystallite size and particle size of the synthesized YNPs measured 1.696 nm and 24.55 nm, respectively. The XPS peaks showed two components with binding energies at 530.940 eV and 532.18 eV due to the bond between O–Y and OH–Y, respectively. Additionally, the ferromagnetic nature of the YNPs was confirmed by VSM analysis. The YNPs were tested for antibacterial activity on six uropathogenic bacteria (S. aureus, S. haemolyticus, E. faecalis, E. coli, K. pneumonia, and P. aeruginosa) using the microdilution assays, to find the minimum inhibitory concentration (MIC) as well as the minimum bactericidal concentration (MBC), the agar well diffusion assay, and antibiofilm screening assays, where they showed bacteriostatic action against all isolates (0.5–1 mg/mL MIC) and significant inhibition of biofilm formation (80% inhibition rate). The antioxidant capacity assessed by 1,1, diphenyl-2-picrylhydrazyl (DPPH) radical scavenging revealed 50% DPPH scavenging. Moreover, docking studies exhibited that YNPs inhibit crucial bacterial enzymes, including DNA gyrase, penicillin-binding proteins, carbapenemase, LasR-binding protein, and dihydropteroate synthase. These findings may explain the mechanisms responsible for the observed antibacterial effects of YNPs. Overall, these findings underscore YNPs as promising candidates for antioxidant and antibacterial applications. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

21 pages, 2080 KiB  
Article
Physicochemical, Functional, Antioxidant, Pasting and FT-IR Spectroscopic Properties of Fermented Acorns and Sorghum Using Traditional Algerian Processes
by Rayene Belmouloud, Hayat Bourekoua, Agnieszka Wójtowicz, Hamida Mahroug, Radia Ayad, Marta Krajewska and Renata Różyło
Processes 2024, 12(8), 1647; https://doi.org/10.3390/pr12081647 - 5 Aug 2024
Viewed by 1137
Abstract
The fermentation of acorns and sorghum is an ancient practice among the inhabitants of northeastern Algeria. This study aimed to establish the traditional fermentation processes of acorns and sorghum through a regional survey conducted in Algeria. Additionally, it investigated the impact of fermentation [...] Read more.
The fermentation of acorns and sorghum is an ancient practice among the inhabitants of northeastern Algeria. This study aimed to establish the traditional fermentation processes of acorns and sorghum through a regional survey conducted in Algeria. Additionally, it investigated the impact of fermentation on the physicochemical, functional, antioxidant, and pasting properties, as well as the FT-IR spectroscopic profiles of the flours derived from these fermented materials. Characteristics of fermented sorghum and acorn flours were compared with those of non-fermented flours. The study included a survey that was carried out in Algeria at the regional level to establish the traditional processes for fermented acorns and sorghum. The key findings reveal the existence of two production methods: the first, the oldest, involves fermentation in underground pits called Matmor, while the second, more recent, is conducted outside the Matmor. Most manufacturers employed the new process outside of the Matmor, usually in various sized and shaped containers to meet market demand. Acorns and sorghum flour, obtained by drying and grinding fermented acorns and fermented sorghum grains according to the process carried out outside the Matmor, are characterized by a unique biochemical, functional, and structural composition. Detailed analysis of the flours showed a significant decrease in their physicochemical properties after fermentation, with a simultaneous overall increase in antioxidant activity. Moreover, FT-IR spectroscopy suggests that fermentation differentially affects protein secondary structure and starch crystallinity. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

11 pages, 3667 KiB  
Article
Incorporation of Liquid WTP Sludge into Compacted Soil–Cement Mixtures
by Julio Marcos Gomes Ribeiro, Carlos Emmanuel Ribeiro Lautenschlager, Matheus Ferreira Alves Santos, Simone do Rocio Ferraz Sabino, Luiz Gustavo de Miranda Vieira, Giovanna Gonçalves and Juliana Martins Teixeira de Abreu Pietrobelli
Processes 2024, 12(7), 1430; https://doi.org/10.3390/pr12071430 - 9 Jul 2024
Viewed by 821
Abstract
The sludge from water treatment plants (WTP) is a waste from the water process. This study evaluated the effect of incorporating water treatment plant (WTP) sludge, replacing the water used in compacted soil–cement mixtures. The materials were characterized by Scanning Electron Microscopy (SEM) [...] Read more.
The sludge from water treatment plants (WTP) is a waste from the water process. This study evaluated the effect of incorporating water treatment plant (WTP) sludge, replacing the water used in compacted soil–cement mixtures. The materials were characterized by Scanning Electron Microscopy (SEM) associated with Energy Dispersive Spectroscopy (EDS) and Atomic Absorption Spectrometry (AAS). The soil, with the addition of liquid WTP sludge, presented an apparent dry specific weight (ƴd) of 1.77 gf·cm−3, the optimum moisture value in the compaction test of 15%, and the cement contents tested were 7, 11, and 14%. The specimens were molded using a WTP sludge–cement–soil mixture under the conditions mentioned above, and the simple compression results showed values within the range of 2.5 to 9.3 MPa, as specified by the Brazilian Technical Standard (NBR) 8491/2012. The hydraulic conductivity performed on the test specimen after 28 days of curing resulted in a coefficient (k) of 7.49 × 10−9 cm·s−1, classified as little permeable. The result obtained from aluminum leaching was 0.12 mg·L−1, within the maximum limit allowed by NBR 10004/2004. Therefore, liquid WTP sludge has a significant capacity for incorporation into the compacted soil–cement mixture and the potential to manufacture ecological bricks, an alternative environmentally sustainable brick. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

10 pages, 3885 KiB  
Article
Fabrication of NiO-CuO/RGO Composite for Lithium Storage Property
by Yuanxiang Fu, Yuxin Chen, Fan Wang and Guoyong Zhou
Processes 2024, 12(7), 1422; https://doi.org/10.3390/pr12071422 - 8 Jul 2024
Viewed by 772
Abstract
The lithium storage performance of binary transition metal oxide/graphene composites as anode materials has been attracting more interest from researchers, based on the fact that binary transition metal oxides and graphene are expected to create a synergistic effect and exhibit improved lithium storage [...] Read more.
The lithium storage performance of binary transition metal oxide/graphene composites as anode materials has been attracting more interest from researchers, based on the fact that binary transition metal oxides and graphene are expected to create a synergistic effect and exhibit improved lithium storage characteristics. In this work, a NiO-CuO/reduced graphene oxide composite (NiO-CuO/RGO) was prepared by an ultrasonic agitation process. When the NiO-CuO/RGO is applied to the anode material for lithium-ion batteries (LIBs), the batteries display high discharge capacities (at 730 mA h/g after 100 cycles at 100 mA/g), high-rate performance (311 mA h/g with 5000 mA/g), and excellent stable cyclability (375 mA h/g within 2000 mA/g after 400 cycles). Such results indicate that the combination of NiO-CuO and RGO leads to enhanced lithium storage performance, for the RGO sheets inhibit the large volume change of binary NiO-CuO and enhance the fast transport of both lithium ions and electrons during the repeated lithium cycling processes. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

13 pages, 3423 KiB  
Article
Design and Characterization of a Continuous Melt Milling Process Tailoring Submicron Drug Particles
by Philip da Igreja, Tim Grenda, Jens Bartsch and Markus Thommes
Processes 2024, 12(7), 1417; https://doi.org/10.3390/pr12071417 - 7 Jul 2024
Viewed by 1258
Abstract
Solid crystalline suspensions (SCSs) containing submicron particles were introduced as a competitive solution to increase dissolution rates and the bioavailability of poorly water-soluble drugs. In an SCS, poorly water-soluble drug crystals are finely dispersed in a hydrophilic matrix. Lately, melt milling as an [...] Read more.
Solid crystalline suspensions (SCSs) containing submicron particles were introduced as a competitive solution to increase dissolution rates and the bioavailability of poorly water-soluble drugs. In an SCS, poorly water-soluble drug crystals are finely dispersed in a hydrophilic matrix. Lately, melt milling as an adapted wet milling process at elevated temperatures has been introduced as a suitable batch manufacturing process for such a formulation. In this work, the transfer from batch operation to a two-step continuous process is demonstrated to highlight the potential of this technology as an alternative to other dissolution-enhancing methods. In the first step, a powder mixture of a model drug (griseofulvin) and a carrier (xylitol) is fed to an extruder, where a uniform suspension is obtained. In the second step, the suspension is transferred to a custom-built annular gap mill, where comminution down to the submicron region takes place. The prototype’s design was based on batch grinding results and a narrow residence time distribution, intended to deliver large quantities of submicron particles in the SCS. The throughput of the mill was found to be limited by grinding media compression. By inclining the mill at an angle, the grinding media position was manipulated, such that compression was avoided. Different states of the grinding media in the grinding chamber were identified under surrogate conditions. This strategy allows the maintenance of an energy-optimized comminution without adaption of the associated process parameters, even at high throughputs. Using this new process, the production of an SCS with 80–90 % submicron particles in a single passthrough was demonstrated. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

12 pages, 899 KiB  
Article
Application of Lactiplantibacillus plantarum LP95 as a Functional Starter Culture in Fermented Tofu Production
by Francesco Letizia, Giovanna Marta Fusco, Alessandra Fratianni, Ilenia Gaeta, Petronia Carillo, Maria Cristina Messia and Massimo Iorizzo
Processes 2024, 12(6), 1093; https://doi.org/10.3390/pr12061093 - 27 May 2024
Viewed by 903
Abstract
Several studies have shown that lactic acid bacteria (LAB) fermentation plays an important role in the development and application of soy-based products and could increase their nutritional values and content of bioactive substances. Lactiplantibacillus plantarum LP95 has shown in previous studies to be [...] Read more.
Several studies have shown that lactic acid bacteria (LAB) fermentation plays an important role in the development and application of soy-based products and could increase their nutritional values and content of bioactive substances. Lactiplantibacillus plantarum LP95 has shown in previous studies to be a promising candidate as a probiotic and microbial culture in fermented soymilk production. In this study, the suitability of Lp. plantarum LP95 as a functional starter culture in tofu production was verified, with a focus on evaluating the isoflavone and amino acid content in the final product after 21 days of storage at 4 °C. Lp. plantarum LP95 was found able to ferment monosaccharides and disaccharides naturally present in soymilk (D-glucose, D-fructose, D-galactose and D-sucrose) after 24 h while leaving the content of galacto-oligosaccharides (stachyose and raffinose) unaffected. The rich amino acid profile of tofu has undergone some quantitative but not qualitative variations compared to the soy milk used, highlighting the high nutritional value of the product obtained. The enzymatic activity of Lp. plantarum LP95 allowed the release of isoflavone aglycones (daidzein, glycitein and genistein) that were not further metabolized during the fermentation phase of soymilk and during storage at 4 °C. In addition, Lp. plantarum LP95 showed a good viability after 21 days of tofu storage at 4 °C. The results obtained highlighted the suitability of this LAB strain to be used as a microbial culture capable of playing a pro-technological role in the production of fermented tofu, which has good nutritional and functional properties. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

14 pages, 3426 KiB  
Article
The Influence of Exogenous Particles on Saliva Rheology
by Agata Penconek, Rafał Przekop, Urszula Michalczuk and Arkadiusz Moskal
Processes 2024, 12(6), 1060; https://doi.org/10.3390/pr12061060 - 22 May 2024
Viewed by 697
Abstract
This study aimed to investigate the effect of exogenous nanoparticles on the rheological properties of artificial saliva. There are four reasons for undertaking this type of research: Firstly, the number of solid particles of various origins present in the air is still high. [...] Read more.
This study aimed to investigate the effect of exogenous nanoparticles on the rheological properties of artificial saliva. There are four reasons for undertaking this type of research: Firstly, the number of solid particles of various origins present in the air is still high. Secondly, nanoparticles (including silver and gold nanoparticles) are increasingly used in food packaging and can migrate into food. Thirdly, saliva is the first biological fluid that comes into contact with exogenous particles. Finally, the function of saliva is also closely related to its rheological properties. Due to the remarkable properties of nano-objects, nanoparticles of various origins in the body may cause effects that have not been realised until now. Therefore, each type of nanoparticle must be tested in terms of its impact on the body/body fluid. We used silver and gold nanoparticles because they are used in the food industry, and diesel exhaust particles because they are standard components of air pollution. The effect of various nanoparticles (e.g., their size and shape) on the rheology of saliva at two temperatures was investigated. The constants of the power law constitutive equation were also estimated. Studies showing the impact of nanoparticles on the rheology of body fluids are rare because it is one of the less obvious ways of their affecting the human body. However, the results show that nanoparticles are not neutral to the biological fluid, which may translate into a change in its properties and thus disturb its functions. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

12 pages, 1785 KiB  
Article
Microwave-Assisted Synthesis of 5-Substituted 3-Amino-1,2,4-triazoles from Aminoguanidine Bicarbonate and Carboxylic Acids
by Mustafa Kemal Gümüş, Mykola Yu. Gorobets and Nesimi Uludag
Processes 2024, 12(3), 573; https://doi.org/10.3390/pr12030573 - 14 Mar 2024
Cited by 2 | Viewed by 1297
Abstract
The effect of the molar ratio between reagents, reaction time and temperature on the yield of 5-substituted 3-amino-1,2,4-triazoles obtained by the direct condensation of carboxylic acids with aminoguanidine bicarbonate under acid catalysis conditions was studied. As a result, a general green straightforward synthesis [...] Read more.
The effect of the molar ratio between reagents, reaction time and temperature on the yield of 5-substituted 3-amino-1,2,4-triazoles obtained by the direct condensation of carboxylic acids with aminoguanidine bicarbonate under acid catalysis conditions was studied. As a result, a general green straightforward synthesis of the title compounds bearing aliphatic substituents or a phenyl ring was developed using sealed reaction vials under controlled microwave synthesis conditions that are suitable for the application of volatile starting carboxylic acids. Our straightforward synthetic method proposed in this work increases the synthetic accessibility of these widely used building blocks and therefore is able to significantly expand the structural diversity of compounds containing a triazole moiety for the needs of drug discovery. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

18 pages, 5910 KiB  
Article
Optimization of Giant Magnetoimpedance Effect of Amorphous Microwires by Postprocessing
by Valentina Zhukova, Paula Corte-Leon, Ahmed Talaat, Mihail Ipatov, Alfonso García-Gomez, Alvaro González, Juan Maria Blanco and Arcady Zhukov
Processes 2024, 12(3), 556; https://doi.org/10.3390/pr12030556 - 12 Mar 2024
Cited by 1 | Viewed by 1027
Abstract
Magnetic microwires with amorphous structures can present a unique combination of excellent magnetic softness and giant magnetoimpedance (GMI) effects together with reduced dimensions and good mechanical properties. Such unique properties make them suitable for various technological applications. The high GMI effect, observed in [...] Read more.
Magnetic microwires with amorphous structures can present a unique combination of excellent magnetic softness and giant magnetoimpedance (GMI) effects together with reduced dimensions and good mechanical properties. Such unique properties make them suitable for various technological applications. The high GMI effect, observed in as-prepared Co-rich microwires, can be further optimized by postprocessing. However, unexpected magnetic hardening and a transformation of the linear hysteresis loop into a rectangular loop with a coercivity on the order of 90 A/m were observed in several Co-rich microwires upon conventional annealing. Several routes to improve magnetic softness and GMI effect in Fe- and Co-rich magnetic microwires are provided. We observed that stress annealing could remarkably improve the magnetic softness and GMI ratio of Co-rich microwires. Thus, almost unhysteretic loops with a coercivity of 2 A/m and a magnetic anisotropy field of about 70 A/m are achieved in Co-rich microwires stress annealed at appropriate conditions. The observed change in hysteresis loops and the GMI effect is explained by stress-annealing-induced anisotropy, which is affected by the stresses applied during annealing and by the annealing temperature. While as-prepared Fe-rich amorphous microwires present a low GMI effect, appropriate postprocessing (annealing and stress annealing) allows for a remarkable GMI ratio improvement (an order of magnitude). The evaluated dependence of the maximum GMI ratio on frequency allows the identification of the optimal frequency band for the studied samples. The origin of stress-annealing-induced anisotropy and related changes in hysteresis loops and the GMI effect are discussed in terms of the relaxation of internal stresses, “back-stresses”, as well as structural anisotropy. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

18 pages, 5384 KiB  
Article
Developing a Quality Control System in a Continuous Hot Air Heating Process in Surimi Seafood Processing Using Image Analysis and Artificial Intelligence
by Won Byong Yoon, Seohee An, Timilehin Martins Oyinloye and Jinho Kim
Processes 2023, 11(11), 3187; https://doi.org/10.3390/pr11113187 - 8 Nov 2023
Cited by 1 | Viewed by 1531
Abstract
In this study, the feasibility of classifying surimi gels during a continuous heating process using an artificial intelligence (AI) algorithm on labeled images was investigated. Surimi paste with varying corn starch concentrations (0%, 5%, and 10%) and moisture content levels (78% and 80%) [...] Read more.
In this study, the feasibility of classifying surimi gels during a continuous heating process using an artificial intelligence (AI) algorithm on labeled images was investigated. Surimi paste with varying corn starch concentrations (0%, 5%, and 10%) and moisture content levels (78% and 80%) from Alaska pollock were analyzed for the subtle physical changes. Rheological characterization and K-means clustering analysis performed on entire images captured from different batches of heated surimi gel indicated a four-stage transformation from its initial state to gel formation with the temperature ranges spanning 25 to <40 °C, 40 to <50 °C, 50 to <55 °C, and 55 to 80 °C. Subsequently, a Convolutional Neural Network (CNN) model based on the temperature classification was designed to interpret and classify these images. A total of 1000 to 1200 images were used for the training, testing, and validation purposes in the ratio 7:1:2. The CNN architecture incorporated essential elements including an input layer, convolutional layers, rectified linear unit (ReLU) activation functions, normalization layers, and max-pooling layers. The CNN model achieved validation accuracy >92.67% for individual mixture composition, 94.53% for classifying surimi samples based on moisture content, and gelation level, and 89.73% for complex classifications involving moisture content, starch concentration, and gelation stages. Additionally, it exhibited high average precision, recall, and F1 scores (>0.92), indicating precision and sensitivity in identifying relevant instances. The success of CNN in non-destructively classifying surimi gels with different moisture and starch contents is demonstrated in this work. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

13 pages, 286 KiB  
Article
Effect of Time and Temperature in Sous-Vide Heat Treatment on Selected Physicochemical Properties of Horsemeat
by Renata Stanisławczyk, Jagoda Żurek, Mariusz Rudy, Marian Gil, Anna Krajewska and Dariusz Dziki
Processes 2023, 11(11), 3126; https://doi.org/10.3390/pr11113126 - 31 Oct 2023
Cited by 3 | Viewed by 1291
Abstract
The sous-vide technique is most commonly used for meat preparation, offering superior nutritional retention, a delicate texture, and enhanced juiciness in the resulting dishes. The purpose of this study was to analyze the effect of time and temperature in sous-vide heat treatment on [...] Read more.
The sous-vide technique is most commonly used for meat preparation, offering superior nutritional retention, a delicate texture, and enhanced juiciness in the resulting dishes. The purpose of this study was to analyze the effect of time and temperature in sous-vide heat treatment on selected physicochemical properties of horsemeat. Samples of m. longissimus thoracis were heated to 55, 60, 65 °C for 4, 8, 12, and 24 h, and the impact of these heat treatment parameters on chemical composition, physicochemical properties, amount of heme pigments, and color parameters of the tested raw material was determined. Horsemeat subjected to sous-vide heat treatment at 55 °C for 4 h was characterized by a high proportion of red color and oxymyoglobin. Sous-vide treatment carried out at low temperatures and for a short period of time reduces the amount of weight loss and the increase in the TBARS index, allowing the preservation of the red color of the raw material studied. Prolonging the duration or increasing the temperature of sous-vide processing results in a deterioration of the mentioned parameters and also leads to significant changes in the chemical composition of horsemeat, including a significant reduction in the water content and increase in the amount of fat in horsemeat. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
16 pages, 5023 KiB  
Article
Soy Protein Nanofibers Obtained by Solution Blow Spinning
by Agata Penconek, Dorota Kasak and Arkadiusz Moskal
Processes 2023, 11(8), 2310; https://doi.org/10.3390/pr11082310 - 1 Aug 2023
Cited by 7 | Viewed by 1314
Abstract
The climate crisis, growing pollution of the environment with waste, and ubiquitous microplastics have encouraged the search for new methods and new opportunities to use natural materials in the least harmful processes. Replacing synthetic materials with raw materials is not only a matter [...] Read more.
The climate crisis, growing pollution of the environment with waste, and ubiquitous microplastics have encouraged the search for new methods and new opportunities to use natural materials in the least harmful processes. Replacing synthetic materials with raw materials is not only a matter of “fashion”, but also a necessity. Therefore, this study aimed to produce fibers from an aqueous solution containing the highest possible concentration of soy protein isolate (SPI) through solution-blowing. As the aqueous solution of SPI has no fiber-forming potential, polyethylene oxide (PEO) was used as the carrier/matrix. The rheology of the aqueous PEO solution and PEO/SPI blends (flow curves, loss modulus, and storage modulus) was then analyzed. The proportions of the PEO/SPI mixtures and the process parameters were determined on this basis. As a result of the conducted research, nanofibers were produced from water solutions of PEO/SPI with a soy protein content of up to 7.88%, with a PEO share of 1.25%. The average diameter of the obtained fibers was 225–495 nm, depending on the process parameters and SPI content—as the SPI content in the PEO/SPI mixture increased, the average fiber diameter decreased. The production of nanofibers with a high soy protein content increases their application possibilities. Firstly, due to a much larger surface area, and secondly, due to the presence of numerous functional groups in the protein structure, which can be a place of attachment for additional compounds that give the obtained nanofibers the desired properties. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

16 pages, 1857 KiB  
Article
Environmental Life Cycle Analysis of Açaí (Euterpe oleracea) Powders Obtained via Two Drying Methods
by Natalia Salgado-Aristizabal, Tatiana Agudelo-Patiño, Sebastian Ospina-Corral, Ignacio Álvarez-Lanzarote and Carlos Eduardo Orrego
Processes 2023, 11(8), 2290; https://doi.org/10.3390/pr11082290 - 31 Jul 2023
Cited by 1 | Viewed by 1484
Abstract
Açaí is a fruit native to Brazil that is found in Colombia, and it is recognized for containing more than 90 compounds with anticancer, anti-inflammatory, and other biological activities. In this study, a cradle-to-gate life cycle analysis (LCA) was conducted for the production [...] Read more.
Açaí is a fruit native to Brazil that is found in Colombia, and it is recognized for containing more than 90 compounds with anticancer, anti-inflammatory, and other biological activities. In this study, a cradle-to-gate life cycle analysis (LCA) was conducted for the production of açaí powder, following the methodology outlined in the ISO 14040 standard. The investigation focused on examining the impact of utilizing or not utilizing the residues generated during the pulp extraction step as fertilizers. Four scenarios were analyzed and compared: (i) production of açaí powder via vacuum drying, (ii) via spray drying, and via the same two types of drying but using residues from the pulping operation as fertilizer (Scenarios 3 and 4). It was found that to produce 1 kg of açaí in a crop cycle, 1.17 kg of CO2 eq is produced. The drying stage in Scenarios 1 and 2 generated 8.04 and 7.93 kg of CO2 eq, respectively. Similarly, when solid waste is used as fertilizer, CO2 emissions barely increased for Scenarios 3 and 4, respectively. To the authors’ knowledge, this is the first carbon footprint study of the production of açaí powder whit these scenarios. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

18 pages, 2653 KiB  
Article
In Situ Indoor Air Volatile Organic Compounds Assessment in a Car Factory Painting Line
by Pedro Catalão Moura, Fausto Santos, Carlos Fujão and Valentina Vassilenko
Processes 2023, 11(8), 2259; https://doi.org/10.3390/pr11082259 - 27 Jul 2023
Cited by 3 | Viewed by 1207
Abstract
Proper working conditions must be one of the employers’ main concerns in any type of company but particularly in work locations where the employees are chronically exposed to hazardous compounds, like factories and production lines. Regarding this challenge, the present research addresses the [...] Read more.
Proper working conditions must be one of the employers’ main concerns in any type of company but particularly in work locations where the employees are chronically exposed to hazardous compounds, like factories and production lines. Regarding this challenge, the present research addresses the mapping of a car factory painting line to possibly toxic volatile organic compounds emitted by all the coatings and chemicals used during the work shifts for the future evaluation of employees’ exposure. For the first time, a Gas Chromatography–Ion Mobility Spectrometry device was employed for the in situ detection of volatile organic compounds in an automotive factory. A total of 26 analytes were detected at nine different locations, of which 15 VOCs were accurately identified. Pure chemical-grade substances were used for the development of the VOC database. Although quantitative analysis was not the goal of this study, a calibration model was presented to one analyte for exemplificative purposes. Relative intensity profiles were plotted for all locations, revealing that some indoor VOCs can reach intensity levels up to 60 times higher than in outdoor air samples. The achieved results proved that the painting line has an abundant number of VOCs emitted from different sources and may lead to serious health risks for the employees. Additional studies shall be developed in the painting line for quantitative evaluation of the existing VOCs and their influence on the employees’ health conditions. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

10 pages, 732 KiB  
Article
Extraction and Characterization of Bromelain from Pineapple Core: A Strategy for Pineapple Waste Valorization
by Alex Fissore, Mauro Marengo, Valentina Santoro, Giorgio Grillo, Simonetta Oliaro-Bosso, Giancarlo Cravotto, Fabrizio Dal Piaz and Salvatore Adinolfi
Processes 2023, 11(7), 2064; https://doi.org/10.3390/pr11072064 - 11 Jul 2023
Cited by 9 | Viewed by 14384
Abstract
Bromelain is a mixture of cysteine endopeptidase usually extracted from pineapple juice and is used for the treatment of various human diseases and in industrial applications. Bromelain demand is quickly increasing, and its recovery from pineapple residues appears to be a sustainable waste [...] Read more.
Bromelain is a mixture of cysteine endopeptidase usually extracted from pineapple juice and is used for the treatment of various human diseases and in industrial applications. Bromelain demand is quickly increasing, and its recovery from pineapple residues appears to be a sustainable waste management strategy. Pineapple core is among the most significant waste materials in the production of canned pineapple and is richer in bromelain than other pineapple residues. In this project, we compared the enzymatic properties and composition of bromelain extracts from either pineapple core or pulp to address the recovery of bioactive bromelain from pineapple core, thus contributing to the valorization of this waste material. Although significant differences were detected in the protein content of the two preparations, no differences could be detected for their proteolytic activity and for the effect of pH on their enzymatic activity. Mass spectrometry (MS) approaches identified the same peptidases in the fruit and in the core. This confirmed the possibility of using pineapple core to obtain relevant amounts of bioactive bromelain by applying a relatively simple procedure, thus paving the way to implementing a circular economy in this specific industrial sector. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

27 pages, 24632 KiB  
Article
Effect of the Freezing Step on Primary Drying Experiments and Simulation of Lyophilization Processes
by Alex Juckers, Petra Knerr, Frank Harms and Jochen Strube
Processes 2023, 11(5), 1404; https://doi.org/10.3390/pr11051404 - 5 May 2023
Cited by 4 | Viewed by 4228
Abstract
Lyophilization is a widely used preservation method for thermosensitive products. It consists of three process steps: freezing, primary and secondary drying. One of the major drawbacks is the long processing time. The main optimization effort was put into the primary drying phase since [...] Read more.
Lyophilization is a widely used preservation method for thermosensitive products. It consists of three process steps: freezing, primary and secondary drying. One of the major drawbacks is the long processing time. The main optimization effort was put into the primary drying phase since it is usually the longest phase. However, the freezing step is of immense importance for process efficiency and product quality. The lack of control during freezing comprises a challenge for process design and tech transfer. In this study, four different freezing steps (shelf-ramped freezing with and without holding step, precooled shelves and an ice fog method for controlled nucleation) are used and their impact on primary drying experiments and simulations is shown. Only the ice fog method is able to control the nucleation temperature leading to low dry layer resistances with low deviations. During the primary drying simulations, the control of the nucleation temperature drastically increases the precision and accuracy of the product temperature prediction. For optimal primary drying design and model predictive control, the nucleation temperature is strongly recommended to be controlled inside a Process Analytical Technology (PAT) concept to achieve reliable and reproducible process conditions. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

Review

Jump to: Research

19 pages, 318 KiB  
Review
Recovery of Lesser-Known Strategic Metals: The Gallium and Germanium Cases
by Jose Ignacio Robla, Manuel Alonso and Francisco Jose Alguacil
Processes 2024, 12(11), 2545; https://doi.org/10.3390/pr12112545 - 14 Nov 2024
Viewed by 658
Abstract
Being not as popular as other elements, such as cobalt, lithium, and rare earth elements, both gallium and germanium have wide use in target developments/industries, thus making them valuable and strategically critical metals. The principal sources for the recovery of both metals are [...] Read more.
Being not as popular as other elements, such as cobalt, lithium, and rare earth elements, both gallium and germanium have wide use in target developments/industries, thus making them valuable and strategically critical metals. The principal sources for the recovery of both metals are secondary wastes of the bauxite (gallium) or zinc (germanium) industries; also, their recycling from waste materials is necessary. The characteristics of these materials make hydrometallurgical operations widely useful in recovering both gallium and germanium from the various sources containing them. The present work reviews the most recent applications (in 2024) of the various operations applied to the recovery of gallium or germanium from various resources. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
18 pages, 2851 KiB  
Review
Challenges and Advances in Tertiary Waste Water Treatment for Municipal Treatment Plants
by Olga Solcova, Martina Dlaskova and Frantisek Kastanek
Processes 2024, 12(10), 2084; https://doi.org/10.3390/pr12102084 - 26 Sep 2024
Viewed by 1463
Abstract
Municipal waste water treatment plants have a fundamental task, which is to rid waste water of toxic and health-threatening organic and inorganic substances, including unwanted microorganisms and other pollutants, with the highest possible efficiency so that the discharged water does not contaminate the [...] Read more.
Municipal waste water treatment plants have a fundamental task, which is to rid waste water of toxic and health-threatening organic and inorganic substances, including unwanted microorganisms and other pollutants, with the highest possible efficiency so that the discharged water does not contaminate the natural environment, which happens in the case of imperfect cleaning. Current WWTPs usually have a preliminary, primary, and secondary stage, and in very few cases even a tertiary stage, which no longer guarantees the sufficient removal of pollutants from waste water. This research presents the current situation in different parts of the world concerning the possibility of solving the current situation regarding the tertiary and quaternary stages of this process, especially in small and rural WWTPs serving up to approx. 10,000 equivalent inhabitants, which could ensure the removal of so-called emerging pollutants, including microplastics, and would stop WWTPs being point sources of environmental contamination. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

28 pages, 3388 KiB  
Review
SPIONs Magnetophoresis and Separation via Permanent Magnets: Biomedical and Environmental Applications
by Xian Wu, Stefano Ciannella, Hyeon Choe, Jacob Strayer, Kai Wu, Jeffrey Chalmers and Jenifer Gomez-Pastora
Processes 2023, 11(12), 3316; https://doi.org/10.3390/pr11123316 - 28 Nov 2023
Cited by 1 | Viewed by 2683
Abstract
Superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as cutting-edge materials, garnering increasing attention in recent years within the fields of chemical and biomedical engineering. This increasing interest is primarily attributed to the distinctive chemical and physical properties of SPIONs. Progress in nanotechnology and [...] Read more.
Superparamagnetic iron oxide nanoparticles (SPIONs) have emerged as cutting-edge materials, garnering increasing attention in recent years within the fields of chemical and biomedical engineering. This increasing interest is primarily attributed to the distinctive chemical and physical properties of SPIONs. Progress in nanotechnology and particle synthesis methodologies has facilitated the fabrication of SPIONs with precise control over parameters such as composition, size, shape, stability, and magnetic response. Notably, these functionalized materials exhibit a remarkable surface-area-to-volume ratio, biocompatibility, and, most importantly, they can be effectively manipulated using external magnetic fields. Due to these exceptional properties, SPIONs have found widespread utility in the medical field for targeted drug delivery and cell separation, as well as in the chemical engineering field, particularly in wastewater treatment. Magnetic separation techniques driven by magnetophoresis have proven to be highly efficient, encompassing both high-gradient magnetic separation (HGMS) and low-gradient magnetic separation (LGMS). This review aims to provide an in-depth exploration of magnetic field gradient separation techniques, alongside a comprehensive discussion of the applications of SPIONs in the context of drug delivery, cell separation, and environmental remediation. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

21 pages, 2390 KiB  
Review
An Overview of Carbon Emission Mitigation in the Food Industry: Efforts, Challenges, and Opportunities
by Ting-Chun Liu, Yi-Ching Wu and Chi-Fai Chau
Processes 2023, 11(7), 1993; https://doi.org/10.3390/pr11071993 - 1 Jul 2023
Cited by 11 | Viewed by 11501
Abstract
The food system plays a significant role in anthropogenic greenhouse gas (GHG) emissions, contributing to over one-third of these emissions. However, there has been limited attention given in the literature on how the food industry can effectively address the carbon issue. This review [...] Read more.
The food system plays a significant role in anthropogenic greenhouse gas (GHG) emissions, contributing to over one-third of these emissions. However, there has been limited attention given in the literature on how the food industry can effectively address the carbon issue. This review aims to bridge this research gap through providing a comprehensive overview of anthropogenic GHG emissions and exploring the role of carbon markets in mitigating climate change, with a specific emphasis on the food industry. It delves into the introduction of emission hotspots within the food industry, examines ongoing efforts in GHG emissions mitigation, and addresses the challenges associated with GHG verification and offsetting. Notably, emission hotspots are primarily found in the farm, manufacturing, and post-production stages of the food industry. The emissions from the farm stage, which are often overlooked, make a significant contribution to overall emissions. Carbon verification encounters limitations due to a lack of standardized methodologies, inaccurate data, and insufficient reporting of emissions. Currently, achieving carbon neutrality without relying on carbon offsets presents a significant challenge for the entire food industry. Comprehensive mitigation strategies and collaboration across agricultural producers and the food manufacturing industry are considered potential solutions to achieve genuine sustainability. Full article
(This article belongs to the Special Issue Features, Reviews and Perspectives for the 10th Anniversary of Processes)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-29
Back to TopTop