High Melting Temperature Research Articles

High-yield production of recombinant human myelin oligodendrocyte glycoprotein in SHuffle bacteria without a refolding step

Experimental autoimmune encephalomyelitis (EAE) is a model for central nervous system (CNS) autoimmune demyelinating diseases such as multiple sclerosis (MS) and MOG antibody-associated disease (MOGAD). Immunization with the extracellular domain of recombinant human MOG (rhMOG), which contains pathogenic antibody and T cell epitopes, induces B cell-dependent EAE for studies in mice. However, these studies have been hampered by rhMOG availability due to its insolubility when overexpressed in bacterial cells, and the requirement for inefficient denaturation and refolding. Here, we describe a new protocol for the high-yield production of soluble rhMOG in SHuffle cells, a commercially available E. coli strain engineered to facilitate disulfide bond formation in the cytoplasm. SHuffle cells can produce a soluble fraction of rhMOG yielding >100 mg/L. Analytical size exclusion chromatography multi-angle light scattering (SEC-MALS) and differential scanning fluorimetry of purified rhMOG reveals a homogeneous monomer with a high melting temperature, indicative of a well-folded protein. An in vitro proliferation assay establishes that purified rhMOG can be processed and recognized by T cells expressing a T cell receptor (TCR) specific for the immunodominant MOG35–55 peptide epitope. Lastly, immunization of wild-type, but not B cell deficient, mice with rhMOG resulted in robust induction of EAE, indicating a B cell-dependent induction. Our SHuffle cell method greatly simplifies rhMOG production by combining the high yield and speed of bacterial cell expression with enhanced disulfide bond formation and folding, which will enable further investigation of B cell-dependent EAE and expand human research of MOG in CNS demyelinating diseases.

4D Printing of Ultra‐High Performance Shape Memory Polymer for Space Applications

Developing thermoplastic polyimide (TPI), capable of handling space conditions, through 4D printing is challenging due to its high melting temperature and inherent viscosity. This study presents 4D printing of TPI for shape memory investigation under repetitive cycles for the first time, exploring its potential for self‐deployable hinges in space devices. 4D‐printed TPI exhibits outstanding shape memory effect (SME) with shape fixity (Rf) up to 100% and shape recovery (Rr) of 100% in first cycle. Rf is noted to be increasing up to third cycle and then fixed to 100% up to tenth cycle, while Rr shows a decreasing trend in subsequent cycle with a drop of 37% in tenth cycle. Moreover, it exhibits extremely high glass‐transition temperature, Tg = 263.10 °C, degradation temperature, Td = 520 °C, and storage modulus of 1600 MPa. Among existing high‐performance (HP) and conventional shape memory polymers (SMPs), 3D‐printed TPI exhibits superior performance. Tg of the TPI is found to be 66.52%, 107.16%, and 62.41%, higher than existing HP‐SMPs, polyether ether ketone (Tg = 158 °C), polyamide (Tg = 127 °C), and polyether ketone ketone (Tg = 162 °C), respectively. This investigation reveals a novel characteristic, the SME, of 4D‐printed TPI with ultra‐high Tg and Td, demonstrating suitability for self‐deployable hinges, contributing to materials engineering and 4D printing.

Transparent and Thermally Stable Rare-Earth-Doped Luminescent Gallate Glass toward Passive Daytime Radiative Cooling Applications.

Currently, the implementation of passive daytime radiative cooling based on zero-energy cooling methodologies primarily focuses on polymers and composite materials, whereas the available literature on all-inorganic materials is relatively few. Here, we present a novel microcrystalline glass material CaGa0.5Al1.5O4 (CGAO), doped with rare-earth elements and prepared by the high-temperature melting method. This material exhibits long-term stability at 200 °C, coupled with an effective infrared radiation cooling function, demonstrating a 4.9 °C temperature reduction at solar noon. The energy transfer and luminescence mechanisms of Tb3+ and Sm3+ doped CGAO glass have been thoroughly investigated, along with thorough assessments of its thermal stability and hardness. The glass exhibits ultrahigh light transmission in the ultraviolet to near-infrared range, with the transmittance reaching 98% in specific spectral bands. Furthermore, it demonstrates superior luminescent thermal stability, retaining 85.6% and 71.2% of its initial luminescence intensity at 423 and 523 K, respectively. The high-temperature resistance and stability and long-term cooling properties render CGAO glass as an optimal candidate for integration into future energy-efficient and sustainable building designs.

New constraints to subduction zone arc and backarc mantle temperatures: a test of the corner flow model

The heat source for the hot volcanic arc of subduction zones and the uniformly warm backarc is not well understood, particularly where backarc extension is absent. In the widely studied corner flow model, the traction of the underthrusting plate drags down the overlying viscous mantle, and the induced shallower seaward flow brings in heat from the landward and deeper asthenosphere. However, earlier comparisons with observations, especially backarc heat flow, gave poor agreement. There are several new constraints to the temperatures and structures above the underthrusting plate and in the backarc, especially those in western North America, for comparison with model predictions. Seismic receiver functions map horizontal boundaries, including the lithosphere-asthenosphere boundary (LAB). Seismic shear wave tomography gives mantle velocity-depth that provides an approximate proxy for temperature. Attenuation of seismic wave speed indicates high temperature or partial melting. The presence of recent backarc volcanics and their geochemistry give the depth and temperature of the LAB. From these constraints in western North America, the LAB reflects ponding of partial melt, is consistently at a depth of 65±3 km and temperature of 1350±25°C, and overlies nearly constant temperature (adiabatic) asthenosphere across the backarc from Mexico to Alaska. These depth and temperature estimates are greatly different from corner flow model predictions. An alternative hypothesis more consistent with these constraints is vigorous small-scale convection in the backarc asthenosphere. Whether or how this convection coexists with the large-scale flow patterns inferred from the interpretation of seismic anisotropy analyses, and to what degree it prevails in the arc-forearc region, deserve further research.

Chain-End Controlled Depolymerization Selectivity in α,α-Disubstituted Propionate PHAs with Dual Closed-Loop Recycling and Record-High Melting Temperature.

Within the large poly(3-hydroxyalkanoate) (PHA) family, C3 propionates are much less studied than C4 butyrates, with the exception of α,α-disubstituted propionate PHAs, particularly poly(3-hydroxy-2,2-dimethylpropionate), P3H(Me)2P, due to its high melting temperature (Tm ∼ 230 °C) and crystallinity (∼76%). However, inefficient synthetic routes to its monomer 2,2-dimethylpropiolactone [(Me)2PL] and extreme brittleness of P3H(Me)2P largely hinder its broad applications. Here, we introduce simple, efficient step-growth polycondensation (SGP) of a hydroxyacid or methyl ester to afford P3H(Me)2P with low to medium molar mass, which is then utilized to produce lactones through base-catalyzed depolymerization. The ring-opening polymerization (ROP) of the 4-membered lactone leads to high-molar-mass P3H(Me)2P, which can be depolymerized by hydrolysis to the hydroxyacid in 99% yield or methanolysis to the hydroxyester in 91% yield, achieving closed-loop recycling via both SGP and ROP routes. Intriguingly, the chain end of the SGP-P3H(Me)2P determines the depolymerization selectivity toward 4- or 12-membered lactone formation, while both can be repolymerized back to P3H(Me)2P. Through the formation of copolymers P3H(Me/R)2P (R = Et, nPr), PHAs with high tensile strength and ductility, coupled with high barriers to water vapor and oxygen, have been created. Notably, the PHA structure-property study led to P3H(nPr)2P with a record-high Tm of 266 °C within the PHA family.

Generation and Selection of Phage Display Antibody Libraries in Fab Format.

Monoclonal antibodies (mAbs) have exceptional utility as research reagents and pharmaceuticals. As a complement to both traditional and contemporary single-B-cell cloning technologies, the mining of antibody libraries via display technologies-which mimic and simplify B cells by physically linking phenotype (protein) to genotype (protein-encoding DNA or RNA)-has become an important method for mAb discovery. Among these display technologies, phage display has been particularly successful for the generation of mAbs that bind to a wide variety of antigens with exceptional specificities and affinities. Rather than multivalent whole antibodies, phage display typically uses monovalent antibody fragments, such as "fragment antigen binding" (Fab), as the format of choice. The ∼50-kDa Fab format consists of four immunoglobulin (Ig) domains on two polypeptide chains (light chain and shortened heavy chain), and exhibits its antigen binding site in a natural configuration found in bivalent IgG and other multivalent Ig molecules. The Fab fragment has a high melting temperature and a low tendency to aggregate, and can be readily converted to natural and nonnatural Ig formats without affecting antigen binding properties, which has made it a favored format for phage display for more than three decades. Here, I briefly summarize some of the approaches used for the generation and selection of phage display antibody libraries in Fab format, from human and nonhuman antibody repertoires.

Petrogenesis and tectonic setting of the proto-tethyan dachaidan ophiolite, North China: insights from clinopyroxene chemistry and whole-rock Sr–Nd–Pb and zircon Hf isotopes

IntroductionThe Dachaidan ophiolites outcrop within an ultrahigh-pressure metamorphic belt along the northern margin of the Qaidam Basin. However, their age, source, and tectonic setting remain still in debate.MethodIn this study, we investigated the geochemistry and geochronology of the Dachaidan ophiolitic gabbros.Results and DiscussionZircon U–Pb dating yielded a crystallization age of 510.0 ± 2.8 Ma and 510.0 ± 2.9 Ma for the gabbro. The gabbros have low SiO2 contents (47.15–50.10 wt.%) and high MgO contents (6.35–9.04 wt.%) and Mg# values (55–74). The total rare earth element (∑REE) contents are 8.35–28.07 ppm, lower than those of normal-type mid-ocean ridge basalts (MORBs), and the gabbros exhibit light REE depletion or flat REE patterns, with small positive Eu anomalies (Eu/Eu* = 1.06–1.40). Trace element patterns are depleted to enriched in Nb and Ta, similar to island arc rocks and MORB. Clinopyroxene thermobarometry indicates the parental magma of the gabbros formed by high-temperature (1,318°C–1,363°C) and medium-pressure (1.27–1.64 GPa) partial melting in a mantle wedge. The gabbros have depleted Sr–Nd–Pb-Hf isotopic compositions, with (87Sr/86Sr)i = 0.704586–0.707441, εNd(t) = 4.7–6.6, and zircon εHf(t) = 7.6–11.4. The age-corrected Pb isotope ratios of these volcanic rocks are variable, with 206Pb/204Pb(t) = 18.085–18.253, 207Pb/204Pb(t) = 15.595–15.614, and 208Pb/204Pb(t) = 37.880–38.148, which are similar to the isotopic compositions of typical Indian MORBs. The source of the Dachaidan ophiolite is inferred to have been depleted mantle. The Dachaidan ophiolite likely formed in a forearc oceanic setting along the northern margin of the Qaidam Basin, during the initial subduction of an oceanic plate.

The evolution and dissolution mechanism of θ-Al2Cu phase and the analysis of precipitation of a novel AlCu phase during elevated aging

The evolution and dissolution mechanism of the θ-Al2Cu precipitates were investigated in this study by transmission electron microscopy (TEM) during the re-aging at high temperatures for a long time. The results advance the current knowledge of dissolution and its associated mechanisms of the θ-Al2Cu phase in AlCu alloys. In this study, the coarsening and dissolution of θ-Al2Cu phase in T6 heat-treated Al4Cu alloy during various times (0−1000h) of re-aging temperature 420 °C were studied experimentally and theoretically. The morphological characterization revealed that the θ-Al2Cu phases gradually increase in size and decrease in volume density during the aging process, which can be attributed to coarsening and dissolution phenomena occurring during re-aging. Additionally, a body-centered tetragonal AlCu phase is precipitated within the θ-Al2Cu phase during the high temperature re-aging process, which is a characteristic of this phase prior to dissolution. Moreover, the primary mechanisms responsible for the high temperature melting of the θ-Al2Cu phase are the formation of the AlCu phase and the initial melting of the Cu-poor region in the θ-Al2Cu phase. The Cu atoms in θ-Al2Cu phase dissolve and diffuse into the Al matrix, forming L12 ordered AlCu solute clusters through long-range diffusion.

Cloning, Expression, and Purification of Phage Display-Selected Fab for Biophysical and Biological Studies.

The antigen-binding fragment (Fab) is the ∼50-kDa monovalent arm of an antibody molecule. In the laboratory, the Fab can be produced via either enzymatic digestion or recombinant expression, and its use facilitates the accurate assessment of affinity and specificity of monoclonal antibodies. The high melting temperature of the Fab, together with its low tendency to aggregate and ready conversion to natural and nonnatural immunoglobulin (Ig) formats (without affecting antigen binding properties), have made it a preferred format for phage display, as well as a tool for accurate assessment of affinity, specificity, and developability of monoclonal antibodies. Here, we outline a strategy to clone, express, and purify human or chimeric nonhuman/human Fabs that have previously been selected by phage display. Fabs purified using this approach, which results in milligram amounts, enable a variety of downstream biophysical and biological assays that ultimately inform the success of phage display library generation and selection.

Paste extrusion‐based 3D printing of fiber‐reinforced ultra high‐temperature ceramics

AbstractUltra–high‐temperature ceramics (UHTCs) are valued for their extremely high melting temperatures and resistance to active oxidation. However, their low fracture strengths and the difficulties in shaping them into complex geometries hamper their widespread application. This study aims to fabricate zirconium diboride–silicon carbide (ZrB2‐SiC) composites reinforced with aligned SiC fibers by formulating suspensions containing a preceramic polymer, ZrB2, and SiC fibers. This study assessed the influence of fiber alignment on electrical and thermal conductivities, as well as on mechanical strength. The results revealed a significant enhancement in thermal conductivity, particularly when the fibers were aligned, effectively doubling it compared with the non‐aligned parts. Additionally, increasing the fiber content significantly improved the fracture strength, with composites containing 22.5 vol% fibers reaching fracture strengths over 57 MPa. However, the final values did not meet the theoretical expectations because the porosity in pyrolyzed parts exceeded 10%. Furthermore, the study demonstrated a 10‐fold increase in electrical conductivity with fiber alignment compared to that for non‐aligned composites. These results highlight the capability of paste extrusion‐based additive manufacturing in tailoring ultra–high‐temperature ceramic matrix composites (UHTCMCs) with aligned fibers, realizing their suitability for aerospace applications.

Enhanced 3 μm emission in Ho3+/Yb3+ co-doped bismuth-fluoride glasses by Gd2O3

In this work, (100-b)(45Bi2O3-40GeO2-15BaF2)-bGd2O3-2Yb2O3-0.5Ho2O3 glass was prepared to use a high-temperature melting method(where b= 0, 2.5, 5, 7.5, 10). The absorption and fluorescence spectra indicate that the optimal Gd2O3 content is 7.5 mol% (BGBG7.5HY), with an Ω2 value of 6.20×10−20 cm2 for the main glass, which is superior to that of BGBG0HY glass. This suggests that the incorporation of Gd2O3 enhances the mid-infrared emission capacity. Raman spectroscopy studies demonstrate that the introduction of Gd₂O₃ results in a substantial influx of oxygen atoms into the glass network, accompanied by a transition of [BiO₆] to [BiO₃] within the glass mesh. This is evidenced by a notable redshift of the characteristic peaks at 509 cm−1 and 677 cm−1 in comparison to BGB glass. The introduction of Gd2O3 also expands the distance between Ho3+/Yb3+ ions, inhibits rare earth ion clusters, improves the Ho3+ luminescence center environment, and thus enhances the 3 μm emission performance of bismuth fluoride glass. The maximum emission cross section is 1.82 × 10−20 cm2 and the maximum gain coefficient is 3.71 cm−1. The results show that the bismuth fluoride glass prepared in this paper is an excellent gain material for mid-infrared fiber lasers.

Self-reducing induced Eu2+/Eu3+ dual-emitting glasses for anti-counterfeiting and optical thermometry

Eu3+/Eu2+ co-doped glasses possess extensive application potential in diverse fields, including light-emitting diodes and sensors, due to their distinctive luminescent characteristics. To date, numerous strategies have been devised to facilitate the coexistence of Eu3+ and Eu2+ in materials. Among them, adjusting the composition of the glass matrix stands out as a straightforward and reproducible approach. Herein, a series of Eu2+/Eu3+ co-doped borosilicate aluminate glasses were successfully synthesized via a high-temperature melting method. By elevating the ratios of B2O3/MgO and Al2O3/BaO in the matrix, a remarkable self-reduction of Eu3+ in ambient air was achieved because of the structural weakness and lower optical basicity for the designed glass matrix. The reduction of Eu3+ is also related to the formation of EuZn• and VΖn′′ defects. Furthermore, by fine-tuning the melting duration and Eu content, we achieved comparable violet and red emission intensities for both Eu2+ and Eu3+ ions. Under UV irradiation with various wavelengths, anti-counterfeiting patterns fabricated from glass powder exhibited precise and pronounced color changes. Notably, the emission intensity ratio of Eu2+/Eu3+ exhibited a consistent decrease as temperature increased, enabling precise temperature determination with exceptional absolute sensitivity (1.22 % K−1) producibility, and discrimination. These findings hold significant implications for the design of Eu3+/Eu2+ co-doped inorganic multifunctional glasses.

High-temperature wear resistance, oxidation resistance and melting loss resistance of plasma cladded Co06–Ni60A composite coating for coppery blast furnace tuyere

High-temperature wear resistance, oxidation resistance and melting loss resistance of plasma cladded Co06–Ni60A composite coating for coppery blast furnace tuyere

Effect of transition metals (Fe, Ru and Os) on the elastic, thermodynamic, electronic, magnetic and thermoelectric properties of three Nd-filled arsenide skutterudites based on first-principles computations

Elastic, electronic, magnetic, thermodynamic, and thermoelectric properties of three neodymium-filled skutterudites NdT4As12 (T = Fe, Ru and Os) have been investigated using density functional theory. The bulk moduli increase with the atomic numbers of the transition metals. All materials are stiff, while the Os compound is the stiffest. A considerable ionic contribution is seen in their inter-atomic bonding. The Fe compound possesses the highest Debye temperature, while the Os compound has the highest melting temperature. GGA+U formalism predicts the semimetallic nature of all the compounds, but their total DOS differs near the Fermi level in both spin channels. The contributions of the Nd-f and T-d electrons differ in the three compounds and two methods. GGA+U predicts the highest magnetic moment in the Fe compound, followed by the Ru and Os compounds. The thermoelectric figure of merit shows no systematic variation with z of the transition metals and in the high temperature region it increases with temperature pretty fast. The highest value of ZT is 0.32 in the Ru compound in the spin-down channel while it is 0.24 in the spin-up channel in the Fe compound, both at 1000 K.

Impact of Runner Size, Gate Size, Polymer Viscosity, and Molding Process on Filling Imbalance in Geometrically Balanced Multi-Cavity Injection Molding.

The injection molding process is one of the most widely used methods for polymer processing in mass production. Three critical factors in this process include the type of polymer, injection molding machines, and processing molds. Polypropylene (PP) is a widely used semi-crystalline polymer due to its favorable flow characteristics, including a high melt flow index and the absence of a need for a mold temperature controller. Additionally, PP exhibits good elongation and toughness, making it suitable for applications such as box hinges. However, its tensile strength is a limitation; thus, glass fiber is added to enhance this property. It is important to note that the incorporation of glass fiber increases the viscosity of PP. Multi-cavity molds are commonly employed to achieve cost-effective and efficient mass production. The filling challenges associated with geometrically balanced layouts are well documented in the literature. These issues arise due to the varying shear rates of the melt in the runner. High shear rate melts lead to high melt temperatures, which decrease melt viscosity and facilitate easier flow. Consequently, this results in an imbalanced filling phenomenon. This study examines the impact of runner size, gate size, polymer viscosity, and molding process on the filling imbalanced problem in multi-cavity injection molds. Tensile bar injection molding was performed using conventional injection molding (CIM) and microcellular injection molding (MIM) techniques. The tensile properties of the imbalanced multi-cavity molds were analyzed. Flow length within the cavity served as an indicator of the filling imbalance. Additionally, computer simulations were conducted to assess the shear rate's effect on the runner's melt temperature. The results indicated that small runner and gate sizes exacerbate the filling imbalance. Conversely, glass fiber-filled polymer composites also contribute to increased filling imbalance. However, foamed polymers can mitigate the filling imbalance phenomenon.

Investigation of high-temperature oxide-metal melts during induction melting in a cold crucible

The object of the study is high-temperature oxide-metal melts obtained in furnaces of induction melting in a cold crucible (IMCC). The results of pilot tests in IMCC furnaces at melt temperatures of more than 2200 оC in air, conducted to study the distribution of components between the oxide and metal phases of a two-phase melt with limited miscibility of components, are presented. The results of physicochemical studies of materials obtained by quenching crystallization of a high-temperature melt are presented, confirming the reduction of silicon and the oxidation of iron with the redistribution of these components between the oxide and metal phases. This experimental result contradicts the well-known Ellingham diagrams and thermodynamic calculations, but a similar effect is observed experimentally in the U–O–Fe system. Thus, the IMCC method allows for the inversion of redox processes in a number of oxide-metal systems, which can be used to obtain new materials and create technologies for high-temperature extraction of target components.

Mechanism of enhancing the SO2-resistance and gaseous arsenic removal performance of Iron-modified pyrolusite

Arsenic pollution in the atmosphere caused by smelting flue gas is a huge environmental challenge, and the removal of gaseous arsenic (As2O3(g)) from smelting flue gas is a matter of urgency. Adsorption has been shown to be an effective method for the removal of As2O3(g) from high temperature smelting flue gas. However, due to the high concentration of SO2 in smelting flue gas, the capture of As2O3(g) by adsorbents is inhibited. In previous studies, the mechanism by which SO2 affects the adsorption of As2O3(g) by pyrolusite (PY) has been clearly elucidated. Therefore, this study proposes a method to improve PY’s resistance to SO2 and its As2O3(g) removal efficiency through Fe modification. Under optimal preparation conditions, the 10Fe/PY adsorbent exhibited an adsorption capacity for As2O3(g) that was nearly uninhibited by SO2. The 10Fe/PY achieving an adsorption capacity of 20.90 mg/g under 7.5 v/v% SO2, which is 1.4 times that of PY. The doped Fe increased the active sites on the 10Fe/PY surface for As2O3(g) adsorption, while preferentially reacting with SO2 to form Fe2(SO4)3, thereby reducing the competition between SO2 and As2O3(g) for the active sites on the adsorbent. The findings provide a theoretical basis for the adsorption and removal of As2O3(g) from high-SO2 smelting flue gas.

Oxidation behaviour of Ti-V-Cr-Nb-Ta and Al-Ti-V-Cr-Ta refractory high entropy alloys: Effects of Nb and Al substitutions

Refractory high entropy alloys (RHEAs) are candidate materials for nuclear and other high-temperature applications, due to their high-temperature strength, good irradiation resistance, and high melting temperatures. However, a significant issue with current RHEAs is that those exhibiting good mechanical properties tend to show poor oxidation resistance, and vice versa. In this paper, the oxidation kinetics of four RHEAs (20Ti-20V-20Cr-20Nb-20Ta, 25Ti-25V-5Cr-20Nb-25Ta, 20Al-20Ti-20V-20Cr-20Ta, and 14Al-24Ti-24V-14Cr-24Ta alloys) were investigated in an air atmosphere at 1000 °C. As-prepared and oxidised samples were characterised by a combination of state-of-the-art microscopy techniques. By replacing Nb with Al, the two Al-containing alloys were observed to form a less porous oxide microstructure, showing significant improvement in their oxidation resistance. As a result of oxygen/nitrogen ingress during oxidation and associated phase-segregation at high temperatures, the hardness of the underlying metal matrix of the RHEAs increased by approximately 5 GPa.

Constructing stable emulsion gel from gelatin and sodium alginate as pork fat substitute: Emphasis on lipid digestion in vitro

This study aimed to develop a gelatin-sodium alginate (G-SA) emulsion gel that can efficiently hold corn oil, as a substitute for pork fat while controlling the digestive behaviors of lipids in vitro. UV, fluorescence, and circular dichroism spectra and surface hydrophobicity measurements of the G-SA mixtures indicated that gelatin and sodium alginate primarily form aggregates through hydrogen bonds and hydrophobic interactions, and the optimum gelatin-to-sodium alginate w/w ratio was identified as 1.9. The final emulsion gel contained 3.15% gelatin and 1.65% sodium alginate (w/w) with a corn oil content of 40% (w/w). G-SA emulsion gel had a higher proportion of polyunsaturated fatty acids (PUFAs, 53.95 g/100 g) than pork fat (15.17 g/100 g). In addition, the G-SA emulsion gel exhibited stable viscoelastic properties without storage and loss moduli changes at increasing shear rates. The G-SA emulsion gel had a higher melting temperature (42.63 °C) than pork fat (35.07 °C). In vitro digestion studies showed that corn oil had a higher free fatty acid release (40.32%) compared to the G-SA emulsion gel (12.66%) and pork fat (8.53%) (P<0.05), indicating that the digestibility of corn oil was reduced in the G-SA emulsion gel. Calcein release experiments revealed that G-SA emulsion gel released the least amount of calcein (P<0.05) during digestion at a slow rate. The G-SA emulsion gel, similar to pork fat, contained evenly distributed digestive particles encapsulating corn oil after in vitro gastric digestion, with the smallest particle size among the treatments. After the in vitro small intestinal digestion phase, the G-SA emulsion gel maintained small droplet sizes with bridging flocculation. The in vitro digesta of the G-SA emulsion gel contained a significantly higher proportion of PUFAs compared to pork fat (P<0.05). Consequently, the G-SA emulsion gel can be a potential substitute for pork fat, offering higher proportions of PUFAs, lower fat content, and controlled lipid digestion with reduced lipid digestibility.

Employing the electrode of different diameters to join dissimilar Al-Cu thin sheets using resistance spot welding

This study aims to clarify the intricate connection between using different electrode tip diameters and the quality of spot joints. By investigating basic principles and process parameters, the research highlights how various combinations of electrode sizes affect weld quality. Specifically, to join aluminum (Al) and copper (Cu), two electrode sizes were employed: 4 mm and 8 mm tip diameter. Given that copper has higher conductivity (398 W/mK) and a higher melting temperature (1085 °C) compared to aluminum (237 W/mK and 660 °C respectively), efforts were made to enhance current density towards the copper side by using the smaller electrode tip diameter (4 mm) on that side. Experiments were conducted using two different combinations of sheet thicknesses (0.5 mm and 1 mm), revealing the need for optimized electrode tip diameter combinations for varying sheet thicknesses and materials with different thermos-physical properties. Overall, this study seeks to deepen our understanding of resistance spot welding, specifically focusing on the importance, challenges, and future prospects associated with varying electrode tip diameters in joining dissimilar metals.