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1.
Heliyon ; 10(17): e37270, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39296149

ABSTRACT

Tropical fruit juices produced from native fruits have been widely marketed by small agribusinesses in the Brazilian semiarid region, necessitating a deeper understanding of the impact of preservation methods on quality parameters. This study aimed to prepare myrtle (Eugenia gracillima Kiaersk.) tropical juice and investigate the effects of physical preservation (90 °C for 60 s) and chemical preservation (potassium sorbate and sodium benzoate) methods. Tropical juice formulations were evaluated after preparation and every 15 days during 60 days of storage in high-density polyethylene bottles at room temperature (25 ± 2 °C). Microbiological parameters, optical microscopy, physicochemical and bioactive parameters, antioxidant capacity, and color parameters were determined. Heat-treated tropical juice showed low counts of all microbiological parameters, but optical microscopy revealed the presence of filamentous fungi after 60 days of storage. Combined use of potassium sorbate and sodium benzoate effectively prevented the development of total yeasts and molds up to 28 days of storage. Bioactive compounds in myrtle pulp contribute to storage stability, mainly total phenolics, estimated at 855.86 mg gallic acid equivalents 100 g-1. The results suggest that it is possible to harness the economic and agroindustrial potential of E. gracillima Kiaersk. fruits for the production of tropical juices, but it is recommended that other technologies be explored, such as aseptic processing or the combined use of physical and chemical methods.

2.
Article in English | MEDLINE | ID: mdl-39316658

ABSTRACT

Developing solid-state batteries (SSB) with a lithium metal electrode (LME) using only one type of solid electrolyte (SE) is a significant challenge since no SE fits all the requirements imposed by both electrodes. A possible solution is using multilayer SSBs with an LME where the drawbacks of each SE are overcome by using layers of different SEs. However, research on inorganic SE1|SE2 heteroionic interfaces is still quite preliminary, especially regarding oxide|sulfide heteroionic interfaces. This work reports the electrochemical investigation of the heteroionic interface between Li6.25Al0.25La3Zr2O12 (Al-LLZO) and two representative materials for sulfide-based SEs: argyrodite-based Li6PS5Cl (LPSCl) and glass-like Li7P3S11 (LPS711). Through in-depth temperature- and pressure-dependent impedance analyses of multilayer symmetric cells at equilibrium (i.e., no current load), the electrical properties of the heteroionic interfaces are assessed. The pressure-dependent kinetic of the Al-LLZO|LPSCl pair is interpreted with the concept of geometric constriction resistance and show that its resistance is lower than for the Al-LLZO|LPS711 pair. Furthermore, the effect of Al-LLZO surface treatment on the electrical properties of the Al-LLZO|LPSCl heteroionic interface is evaluated. Such investigation shows that the value of the interface activation energy decreases when the Al-LLZO surface is heat treated, revealing a significant influence of the carbonate/hydroxide passivation layer on the heteroionic interface. Additionally, by cycling the symmetric cell for 900 h at 1.0 mAh·cm-2, it is revealed that the Al-LLZO|LPSCl interface has a lower impedance increase than the Al-LLZO|LPS711 interface, especially if the Al-LLZO is heat treated. With this work, we highlight that the oxide|argyrodite combination can be a promising candidate for multilayer SSBs with an LME. However, we show that an optimized LLZO surface treatment and chemical analysis of the interface are recommended for future research.

3.
Heliyon ; 10(16): e35817, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39253227

ABSTRACT

Faba bean is a protein-rich starchy grain that is underutilised in the UK. The starch of faba bean can be modified using environmentally friendly methods like dry heat treatment (DHT) to enhance functional and its physicochemical properties. This study investigated the impact of dry heat temperature and time on the structure, functional and physicochemical properties of faba bean starch (FBS) using a two-factor central composite rotatable design. Factors (DHT temperature:100-150 °C and DHT time:0.5-5 h) with their respective α mid-point values led to 13 experimental runs. Selected pasting and functional properties were measured as response variables. Corn starch was included as a reference and compared with the FBS modified using the optimized conditions. DHT increased peak (approx. 2205-2267 cP), final (approx. 3525-3642 cP) and setback (approx. 1887-1993 cP) viscosities but decreased the amylose content of FBS. Colour, as measured by lightness value, morphology and crystalline type were not altered but the starches showed a loss of order and an increase in crystallinity after DHT. FBS appeared resilient to DHT but showed higher swelling power and pasting properties compared to the corn starch control. The optimum DHT conditions to produce starch with desirable properties are a temperature of 100 °C for 0.1716 h, with a desirability factor of 66 %.

4.
Heliyon ; 10(16): e36099, 2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39253260

ABSTRACT

The improvement and verification of fluid dynamics simulation on temperature uniformity during the heat treatment of ring pieces are investigated in this study. The accuracy of the temperature field model is validated by comparing the simulation results with the measured temperatures. The findings reveal that the vortex generated near the furnace wall during heat treatment significantly affects the uniformity of the temperature field. To improve this, adjustments are made to the placement of ring pieces based on an experimentally validated fluid dynamics simulation model, and subsequent calculations are performed on this adjusted model. It is observed that these adjustments greatly enhance temperature uniformity in the heating process, with a 39.06 % improvement in medium-temperature zone (732.32-743.69 k) within the furnace compared to the original model. Additionally, surface temperatures of ring pieces in another medium-temperature zone (668.89-691.11 k) show a 34.54 % improvement in comparison to those predicted by the original model.

5.
Food Res Int ; 195: 114971, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39277268

ABSTRACT

Heat treatment and pH are crucial factors in the formulation and processing of food and beverages; thus, a thorough understanding of the impact of these factors on the interactions between bioactive constituents and proteins is essential to developing effective protein-based delivery systems. This study explores the influences of pH (ranged from 1.5 to 7.5) and preheating treatment on the characteristics of caseinates-lutein (LU)/zeaxanthin (ZX) complexes and evaluates the potential application of caseinates as protective carriers in xanthophyll-fortified beverages. The properties and interactions of caseinates and two xanthophylls were systematically investigated utilizing a range of spectroscopic techniques, including ultraviolet-visible (UV-Vis) spectroscopy, dynamic light scattering (DLS), fluorescence spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. Caseinates were bound to LU/ZX with a binding constant of the order 105 M-1. Furthermore, ZX exhibited a higher affinity for caseinates than LU. In particular, the decreased pH level of complex formulation and the preheating of caseinates at 85 °C strengthened the binding affinity between LU/ZX and caseinates. The caseinate-LU/ZX complexes effectively improved the chemical stability of LU/ZX and achieved a bioaccessibility rate of over 70 %. This study provides a guide for developing commercially available xanthophyll-fortified beverages and further expanding the application of caseinates as encapsulation carriers for extremely hydrophobic nutrients in the food industry.


Subject(s)
Caseins , Hot Temperature , Lutein , Zeaxanthins , Hydrogen-Ion Concentration , Lutein/chemistry , Zeaxanthins/chemistry , Caseins/chemistry , Food Handling/methods , Biological Availability , Food, Fortified , Spectroscopy, Fourier Transform Infrared , Beverages
6.
Front Bioeng Biotechnol ; 12: 1450331, 2024.
Article in English | MEDLINE | ID: mdl-39234269

ABSTRACT

Radiofrequency ablation (RFA) is a local treatment modality for primary liver cancers. Although various input parameters of the RF generator have been adjusted to improve the ablation ranges, the limited ablation ranges remain an obstacle to RFA. This study aimed to compare the ablation ranges and efficacy of sine and square electrical waveforms in a mouse tumor model. An RF generator with an adjustable electrical waveform was developed, and its ablation range in the porcine liver was compared. For all RF parameters, the square electrical waveform ablation range was greater than that of the sine electrical waveform (all p < 0.001) in the porcine liver. The 45 BALB/c nude mice were used to evaluate the efficacy of the two electrical waveforms after the RFA. The mean tumor volume in the square group was significantly lower than that in the sine group (p < 0.001), indicating a higher survival rate (60%). The cellular coagulative necrosis, inflammatory cell infiltration, heat shock proteins, cellular necrosis, and tumor necrosis were significantly greater in square electrical waveform than in sine electrical waveform (all; p < 0.05). RFA with square electrical waveforms has therapeutic potential for tumor management with an enhanced ablation range.

7.
Materials (Basel) ; 17(17)2024 Aug 30.
Article in English | MEDLINE | ID: mdl-39274709

ABSTRACT

Gas-induced porosity is almost inevitable in additively manufactured aluminum alloys due to the evaporation of low-melting point elements (e.g., Al, Mg, and Zn) and the encapsulation of gases (e.g., hydrogen) during the multiple-phase reaction in the melt pool. These micropores are highly unstable during post-heat treatment at elevated temperatures and greatly affect mechanical properties and service reliability. In this study, the AlSi10Mg samples prepared by LPBF were subjected to solution heat treatment at 560 °C for 0.5 and 2 h, followed by artificial aging at 160 °C, 180 °C and 200 °C, respectively. The defect tolerance of gas porosity and associated damage mechanisms in the as-built and heat treated AlSi10Mg alloy were elucidated using optical, scanning electron microscopic analysis, X-ray micro computed tomography (XCT) and room temperature tensile testing. The results showed the defect tolerance of AlSi10Mg alloy prepared by LPBF was significantly reduced by the artificial aging treatment due to the precipitation of Mg-Si phases. Fracture analysis showed that the cooperation of fine precipitates and coarsened micropores assists nucleation and propagation of microcracks sites due to stress concentration upon tensile deformation and reduces the tensile elongation at break.

8.
Food Chem ; 461: 140825, 2024 Dec 15.
Article in English | MEDLINE | ID: mdl-39151352

ABSTRACT

The research compared the combined effect of ultrasound (160 W, 2 min), oleic acid (15%, 11 h), and moist-heat treatment (HMT, 25% moisture content, 110 °C, 2 h) with their individual treatment on rice grains. The results showed that ultrasound treatment created pores and cracks in the rice grains, facilitating an easier penetration for oleic acid to develop amylose-oleic acid complex during HMT. Compared to native raw rice (NR), both single and combined treatments significantly altered the morphology, reduced swelling power and solubility, enhanced hydrophilicity, thus changing the moisture distribution, thermal and pasting characteristics. Notably, the combined treatment of three techniques significantly increased the relative crystallinity, accompanied by the highest digestive resistance, and the content of resistant starch was increased from 20.53% in NR to 31.75%, much higher than the other treatments. These findings provide potential for the manufacturers to rationally and flexibly employ this low digestible rice in health food products.


Subject(s)
Digestion , Hot Temperature , Oleic Acid , Oryza , Oryza/chemistry , Oryza/metabolism , Oleic Acid/chemistry , Food Handling , Solubility , Starch/chemistry , Starch/metabolism , Amylose/chemistry , Amylose/metabolism , Amylose/analysis
9.
Materials (Basel) ; 17(16)2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39203210

ABSTRACT

The interest in hydrogen is rapidly expanding because of rising greenhouse gas emissions and the depletion of fossil resources. The current work focuses on employing affordable Al alloys for hydrogen production and storage to identify the most efficient alloy that performs best in each situation. In the first part of this work, hydrogen was generated from water electrolysis. The Al alloys that are being examined as electrodes in a water electrolyzer are 1050-T0, 5052-T0, 6061-T0, 6061-T6, 7075-T0, 7075-T6, and 7075-T7. The flow rate of hydrogen produced, energy consumption, and electrolyzer efficiency were measured at a constant voltage of 9 volts to identify the Al alloy that produces a greater hydrogen flow rate at higher process efficiency. The influence of the electrode surface area and water electrolysis temperature were also studied. The second part of this study examines these Al alloys' resistance to hydrogen embrittlement for applications involving compressed hydrogen gas storage, whether they are utilized as the primary vessel in Type 1 pressure vessels or as liners in Type 2 or Type 3 pressure vessels. Al alloys underwent electrochemical charging by hydrogen and Charpy impact testing, after which a scanning electron microscope (SEM) was used to investigate the fracture surfaces of both uncharged and H-charged specimens. The structural constituents of the studied alloys were examined using X-ray diffraction analysis and were correlated to the alloys' performance. Sensitivity analysis revealed that the water electrolysis temperature, electrode surface area, and electrode material type ranked from the highest to lowest in terms of their influence on improving the efficiency of the hydrogen production process. The 6061-T0 Al alloy demonstrated the best performance in both hydrogen production and storage applications at a reasonable material cost.

10.
Materials (Basel) ; 17(16)2024 Aug 19.
Article in English | MEDLINE | ID: mdl-39203284

ABSTRACT

Lithium-ion batteries are superior energy storage devices that are widely utilized in various fields, from electric cars to small portable electric devices. However, their susceptibility to thermal runaway necessitates improvements in battery case materials to improve their safety. This study used electrochemical analyses, including open-circuit potential (OCP), potentiodynamic polarization, and critical pitting temperature (CPT) analyses, to investigate the corrosion resistance of super duplex stainless steel (SAF 2507) applied to battery cases in relation to post-weld heat treatment (PWHT) time. The microstructure during the manufacture, laser welding, and PWHT was analyzed using field-emission scanning electron microscopy, X-ray diffraction, and electron backscatter diffraction, and the chemical composition was analyzed using dispersive X-ray spectroscopy and electron probe micro-analysis. The PWHT increased the volume fraction of austenite from 5% to 50% over 3 min at 1200 °C; this increased the OCP from -0.21 V to +0.03 V, and increased the CPT from 56 °C to 73 °C. The PWHT effectively improved the corrosion resistance, laying the groundwork for utilizing SAF 2507 in battery case materials. But the alloy segregation and heterogeneous grain morphology after PWHT needs improvement.

11.
Materials (Basel) ; 17(16)2024 Aug 21.
Article in English | MEDLINE | ID: mdl-39203319

ABSTRACT

Electrodeposited chromium plating continues to be widely used in a number of specialized areas, such as weapons, transport, aerospace, etc. However, the formation of texture, hydrogen content and residual stress can degrade the serviceability and lead to material failure. The effect of post heat treatment processes on the relationship of texture, hydrogen content, residual stress and corrosion resistance of hexavalent [Cr(VI)] chromium coatings deposited on Cr-Ni-Mo-V steel substrates was investigated. Macrotexture was measured by XRD. Microtexture, dislocation density and grain size were studied by EBSD. With the increase of the heat treatment temperature, it was found that the fiber texture strength of the (222) plane tended to increase and subsequently decrease. Below 600 °C, the increase in the (222) plane texture carried a decrease in the hydrogen content, residual stress, microhardness and an increase in the corrosion resistance. In addition, crack density and texture strength were less affected by the heat treatment time. Notably, relatively fewer crack densities of 219/cm2, a lower corrosion current density of 1.798 × 10-6 A/dm2 and a higher microhardness of 865 HV were found under the preferred heat treatment temperature and time of 380 °C and 4 h, respectively. The hydrogen content and residual stress were 7.63 ppm and 61 MPa, with 86% and 75% reduction rates compared to the as-plated state, respectively. In conclusion, in our future judgement of the influence of heat treatment on coating properties, we can screen or determine to a certain extent whether the heat treatment process is reasonable or not by measuring only the macrotexture.

12.
Materials (Basel) ; 17(16)2024 Aug 22.
Article in English | MEDLINE | ID: mdl-39203334

ABSTRACT

The paper aims at documenting the material employed in 1942 for the fabrication of an exhaust valve for a Harley-Davidson WLA/WLC motorcycle and assesses the material features with modern steel standard specifications and treatment. Facing properties of the original historical parts of technical heritage objects according to modern standards is a rare discipline, as these objects are nowadays in collections of museums or private collectors and experimental instrumental analyses are strictly forbidden. In this case, a preserved accessible unused surplus replacement kit was studied. The microstructure was assessed by light optical and scanning electron microscopy, electron probe micro-analysis and by heat treatment-hardness correlation. It was found that the valve was made of Silchrome 1 steel in coherence with the X45CrSi9-3 steel modern material standard, but with a slightly higher content of phosphorus and sulfur. Microscopic observations and hardness profile testing suggested a tempered martensitic structure (sorbite) with very fine grains uniformly distributed in the valve and an even heat treatment. Heat treatment-hardness experimentation demonstrated that the original heat treatment cannot be achieved by the modern standard procedure. The tempering temperature was surprisingly deduced to be lower than the recommended one according to the modern standard, which contrasts with the service temperature indicated in the contemporary motorcycle mechanics handbook.

13.
Food Chem ; 461: 140924, 2024 Dec 15.
Article in English | MEDLINE | ID: mdl-39181042

ABSTRACT

High-sensitivity 4D label-free proteomic technology was used to identify protein components related to gluten quality and celiac disease (CD) in strong-gluten wheat cultivar KX 3302 and medium-gluten wheat cultivar BN 207. The highly expressed storage protein components in KX3302 were high-molecular-weight-glutenin-subunits (HMW-GSs), α-gliadin, and globulin, whereas those in BN207 were γ-gliadin, low-molecular-weight-glutenin-subunits (LMW-GSs) and avenin-like proteins. In addition, BN207 had more upregulated metabolic proteins than KX3302. The abundance of storage proteins increased during dough formation. After heat treatment, the upregulated proteins accounted for 57.53 % of the total proteins, but the downregulated storage proteins accounted for 79.34 % of the total storage proteins. In cultivar KX3302, CD proteins mainly included α-gliadin and HMW-GSs, whereas in BN207, they were mainly γ-gliadin and LMW-GSs. Thermal treatment significantly reduces the expression levels of CD-related proteins. These findings provide a new perspective on reducing the content of CD-related proteins in wheat products.


Subject(s)
Bread , Celiac Disease , Flour , Glutens , Hot Temperature , Proteomics , Triticum , Triticum/chemistry , Triticum/metabolism , Celiac Disease/diet therapy , Celiac Disease/metabolism , Flour/analysis , Glutens/analysis , Glutens/metabolism , Humans , Bread/analysis , Plant Proteins/analysis , Plant Proteins/metabolism , Plant Proteins/genetics , Gliadin/analysis , Gliadin/metabolism , Gliadin/chemistry
14.
Food Chem ; 461: 140958, 2024 Dec 15.
Article in English | MEDLINE | ID: mdl-39191037

ABSTRACT

In this study, the oxidation of egg yolk lipids (EYL) by salt-induced heat and non-heat treatments was investigated for quality and flavor. The correlation between physicochemical properties, lipid oxidation and antioxidant activity was modeled using partial least squares discriminant analysis (PLS-DA). The results indicated that the prolonged salt-induced synergistic heat treatment produced the highest level of lipid oxidation, antioxidant activity and oil exudation, along with the lowest level of polyunsaturated fatty acid content. In addition, higher contents of pyrazines and fewer acid species were detected, which was not the case with the salt-free heat treatment. In total, 14 identical volatile organic compounds (VOCs) were produced, yet their overall flavor profiles determined by the electronic nose would remain dramatically distinguished. Therefore, heat treatment was particularly critical for lipid oxidation and the generation of aromatic compounds, implying that heat-treated EYL induced by salt is a flavor component with good antioxidant potential.


Subject(s)
Egg Yolk , Flavoring Agents , Hot Temperature , Lipids , Taste , Egg Yolk/chemistry , Lipids/chemistry , Animals , Flavoring Agents/chemistry , Oxidation-Reduction , Volatile Organic Compounds/chemistry , Antioxidants/chemistry , Sodium Chloride/analysis , Sodium Chloride/chemistry , Chickens , Food Handling
15.
Article in English | MEDLINE | ID: mdl-39186888

ABSTRACT

This study introduces an efficient on-column refolding and purification method for preparing nanobodies (Nbs) expressed as inclusion bodies and fusion proteins. The HisTrapTM FF system was successfully employed for the purification of the fusion protein FN1-ΔI-CM-2D5. The intein ΔI-CM cleavage activity was activated at 42 °C, followed by incubation for 4 h. Leveraging the remarkable thermal stability of Nbs, 2D5 was further purified through heat treatment at 80 °C for 1h. This method yielded up to 107.2 mg of pure 2D5 with a purity of 99.2 % from just 1L of bacterial culture grown in a shaker flask. Furthermore, this approach successfully restored native secondary structure and affinity of 2D5. Additionally, the platform was effectively applied to the refolding and purification of a polystyrene-binding nanobody (B2), which exhibited limited expression in the periplasmic and cytoplasmic spaces of E. coli. This endeavor resulted in the isolation of 53.2 mg of pure B2 Nb with a purity exceeding 99.5 % from the same volume of bacterial culture. Significantly, this approach restored the native secondary structure of the Nbs, highlighting its potential for addressing challenges associated with expressing complex Nbs in E. coli. Overall, this innovative platform provides a scientifically rigorous and reproducible method for the efficient preparation of Nbs, offering a valuable tool for antibody research and development.


Subject(s)
Escherichia coli , Inclusion Bodies , Protein Refolding , Recombinant Fusion Proteins , Single-Domain Antibodies , Inclusion Bodies/chemistry , Inclusion Bodies/metabolism , Single-Domain Antibodies/chemistry , Single-Domain Antibodies/isolation & purification , Single-Domain Antibodies/genetics , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism
16.
Foods ; 13(16)2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39200460

ABSTRACT

The objective of this work was to evaluate the properties of beverages formulated with Brazil nuts (Bertholletia excelsa Bonpl) and bocaiuva almonds (Acrocomia aculeata (Jacq.) Lodd. Ex Mart.). Five beverages were developed with Brazil nut, bocaiuva almond, and water (m/m/v), as follows: (i) NB, nut:water, 1:10; (ii) AB, almond:water, 1:10; (iii) NAB1, 1:0.1:10, nut:almond:water; (iv) NAB5, nut:almond:water, 1:0.5:10; and (v) NAB10, nut:almond:water, 1:1:10. The physicochemical, chemical, technological, and microbiological parameters were evaluated. After heat treatment (HT) and enrichment with minerals, the beverages that demonstrated stability in these characteristics were tested in a biological assay. The physical and biochemical parameters of male Wistar rats were evaluated after administering beverages for 28 days. HT decreased the total phenolic content and the antioxidant activity; however, it guaranteed microbiological safety. Mineral supplementation changed the colors and increased the pH values of the beverages. After the beverages were administered, the Wistar rats in the (i) NB group showed decreases in retroperitoneal adipose tissue, total cholesterol, and triglycerides; (ii) those in the AB group exhibited decreased triglycerides contents; and (iii) those in the NAB10-group presented decreased liver weights. The beverages evaluated in this study demonstrate a protective effect against risk factors such as fat accumulation in the liver, retroperitoneal adipose tissue, and hypercholesterolemia.

17.
Materials (Basel) ; 17(15)2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39124360

ABSTRACT

High-carbon steels are normally used as tool materials. The use of such steels for construction is limited due to their increased brittleness and poor weldability. However, it appears that high-carbon steels possess certain hidden reserves for enhanced plasticity and strength if properly heat-treated. An unconventional heat treatment was applied to carbon eutectoid steel (0.8 wt.% C) in order to increase its strength and impact toughness simultaneously. Samples for tensile and impact testing were held at 800 °C for different time ranges from 3 min to 9 min with subsequent cooling in oil. It was established that for each type of sample, an optimal holding time exists that is responsible for increased strength and high impact toughness. The hardness and microhardness levels of the surface and under-surface regions of the samples reached 390 HV after optimal heat treatment. An X-ray revealed a shift of the (211)α-peak to the lower 2-theta angles after heat treatment with the optimal holding time; this indicates an increase in carbon content in alpha solid solutions of approximately 0.12 wt.%. Thus, a nanostructured mixture of low-carbon martensite and thin cementite plates is formed in the under-surface region of carbon eutectoid steel after heat treatment, with a controlled holding time at the austenitizing temperature.

18.
Materials (Basel) ; 17(15)2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39124433

ABSTRACT

This study investigates the effects of post-weld heat treatment (PWHT) on the microstructures and mechanical properties of plasma arc-welded 316 stainless steel. The experimental parameters included the solid solution temperatures of 650 °C and 1050 °C, solid solution durations of 1 h and 4 h, and quenching media of water and air. The mechanical properties were evaluated using Vickers hardness testing, tensile testing, scanning electron microscopy (SEM), and optical microscopy (OM). The highest ultimate tensile strength (UTS) of 693.93 MPa and Vickers hardness of 196.4 in the welded zone were achieved by heat-treating at 650 °C for one hour, quenching in water, and aging at 500 °C for 24 h. Heat-treating at 650 °C for one hour, followed by quenching in water and aging at 500 °C for 24 h results in larger dendritic δ grains and contains more σ phase compared to the other conditions, resulting in increased strength and hardness. Additionally, it shows wider and shallower dimple structures, which account for its reduced impact toughness.

19.
Polymers (Basel) ; 16(15)2024 Aug 02.
Article in English | MEDLINE | ID: mdl-39125227

ABSTRACT

In response to the phenomenon of interlayer transport channel swelling caused by the hydration of oxygen-containing functional groups on the GO membrane surface, a moderate heat treatment method was employed to controllably reduce the graphene oxide (GO) membrane and prepare a reduced GO composite nanofiltration membrane (mixed cellulose membrane (MCE)/ethylenediamine (EDA)/reduced GO-X (RGO-X)). The associations of different heat treatment temperatures with the hydrophilicity, interlayer structure, permeability and dye/salt rejection properties of GO membranes were systematically explored. The results indicated that the oxygen-containing groups of the GO membrane were partially eliminated after heat treatment, and the hydrophilicity was weakened. This effectively weakened the hydration between the GO membrane and the water molecules and inhibited the swelling of the oxidized graphene membrane. In the dye desalination test, the MCE/EDA/RGO membrane exhibited an ultra-high rejection rate of over 97% for methylene blue (MB) dye molecules. In addition, heat treatment increased the structural defects of the GO membrane and promoted the fast passage of water molecules via the membrane. In pure water flux testing, the water flux of the membrane remained above 46.58 Lm-2h-1bar-1, while the salt rejection rate was relatively low.

20.
Food Res Int ; 192: 114828, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39147517

ABSTRACT

To enhance the drying quality of potato slices, this investigation employed a microwave heating (MH) combined with ethanol osmotic dehydration (EOD) pretreatment strategy to improve the quality of explosion puffing drying (EPD). This paper systematically investigated the effects of different pretreatment methods (no treatment, HAD, MH, EOD, MH+EOD) on the quality and physicochemical properties of potato slices subjected to CO2-EPD. The results showed that after MH and EOD pretreatments, the internal pores of the potato slices exhibited a uniform porous structure. The MH+EOD+CO2-EPD treatment demonstrated superior expansion, crispness, hardness, and color, with higher retention rates of vitamin C and protein. The measurements were an expansion ratio of 2.15, hardness of 1290.01 g, crispness of 745.94 g, ΔE of 6.54, protein content of 1.99 g/100 g, and VC content of 17.33 mg/100 g. Additionally, the study explored the effects of microwave power, microwave drying time, ethanol concentration, and ethanol soaking time on the expansion ratio, hardness, crispness, protein content, VC content, and color. MH+EOD+CO2-EPD is an environmentally sustainable and efficient solution with potential for widespread industrial application to enhance processing quality and economic benefits.


Subject(s)
Carbon Dioxide , Desiccation , Ethanol , Food Handling , Microwaves , Solanum tuberosum , Solanum tuberosum/chemistry , Carbon Dioxide/analysis , Desiccation/methods , Food Handling/methods , Color , Ascorbic Acid/analysis , Hardness , Plant Tubers/chemistry , Plant Tubers/radiation effects
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