International Journal of Materials Science and Technology Studies

Abstract: In this paper, the mechanism of plasma effect in semiconductor materials and its remarkable influence on the performance of optoelectronic devices are discussed in depth. Plasma effect, as a special physical phenomenon that can be excited in semiconductor, forms a high concentration of free electron and hole plasma state in semiconductor through high intensity illumination or electric field, thus significantly changing the optical and electrical properties of materials. In optics, the plasma effect enhances the nonlinear optical response of semiconductors and improves the ability of light absorption and refractive index control. In electricity, it changes the conductivity of semiconductors, optimizes the current-voltage characteristics, and may lead to self-organization phenomena such as the formation of quantum dots. In light-emitting diodes (LED), the plasma effect significantly improves the luminous efficiency, brightness and stability of LED by enhancing the radiation recombination process. In photodiode, plasma effect promotes the effective separation and transmission of photo-generated carriers, improves the response speed and sensitivity of the device, and optimizes the spectral response range. For solar cells, plasma effect is expected to further improve their photoelectric conversion efficiency by enhancing light absorption and improving charge separation efficiency. In addition, in the laser, the plasma effect also shows the potential to enhance the inversion of particle number in the gain medium and improve the stability of laser output. Read More

Abstract: In order to clarify the functional integration modes and performance optimization directions of semiconductor chips and integrated circuits in smart electronic devices, this paper combines the 2024-2025 measured industrial data of the semiconductor industry to sort out the development history of chip integration technologies, analyze the practical roles of SoC (System on Chip) and Chiplet architectures in functional integration, explore the improvement effects of low-power design, advanced packaging and new materials on chip performance, and summarize the design concepts for the collaborative optimization of chip functionality and performance. Research indicates that by 2025, high-end advanced packaging has become the core technical support for heterogeneous chip integration; the shipment volume of advanced-process high-end SoCs for smartphones continues to rise. Chiplet and high-density interconnect (HDI) technologies can effectively improve the functional integration density of chips, and relevant technological innovations have continuously broken through the performance limitations of traditional silicon-based processes. The optimization strategies summarized in this paper based on practical industrial applications can provide feasible practical references for the design and performance upgrading of chips used in smart electronic devices. Read More

Abstract: Using density functional theory calculations, the thermoelectric properties of LaZnSbO have been systematically investigated. The bulk LaZnSbO features a natural super lattice structure with low electrical conductivity and low thermal conductivity. The band structure reveals that it is a direct gap semiconductor having a band gap of 0.73eV. Doping can enhance its conductivity and thereby raise its ZT value. At a temperature of 900K, close to the carrier concentration 2.5×1019/cm3, the p-type doped system shows a Seebeck coefficient of 313μVκ-1, a conductivity of 2.06×104Sm-1 and a power factor of 0.78×10-3Wm-1κ-2. As a result, a thermoelectric figure of merit (ZT) reaches a maximum value of 1.43. Read More

Abstract: In this paper, ZnS/SnO2 composite photocatalysts with different molar ratios were prepared by a two-step hydrothermal method. The influence of ZnS composite ratio on the material structure, morphology, optical properties and photocatalytic performance was systematically investigated. XRD and XPS results indicate that the SnO precursor is completely transformed into rutile SnO2 during the hydrothermal process, and ZnS is composited on the SnO2 surface in the form of cubic sphalerite, forming a heterostructure rather than a solid solution. SEM, TEM and EDS show that the composite exhibits a porous nano-aggregate morphology with a close heterojunction interface formed between ZnS and SnO2. BET analysis reveals that the material possesses a mesoporous structure with a specific surface area of 14.36 m2/g. UV-vis absorption spectra show that the absorption edge of the composite is red-shifted, extending the photoresponse range to the visible region. The photocatalytic degradation experiments of rhodamine B (RhB) demonstrate that the composite with a ZnS ratio of 80% (0.8-ZnS/SnO2) exhibits the best performance, achieving a degradation rate of 93.52% within 70 min and a reaction rate constant of 3.74×10-2 min-1, which is about 5 times that of commercial P25. Cyclic catalytic tests prove that the composite has good reusability and photostability. This study provides a feasible synthesis strategy and structural optimization basis for constructing efficient type II heterojunction photocatalysts. Read More

Abstract: A polyacrylamide/calcium alginate (PAM/CaAlg) hybrid hydrogel membrane was prepared by UV-initiated free-radical polymerization and subsequent Ca2+ ionic crosslinking. Then the PAM/CaAlg membrane was further treated with diammonium hydrogen phosphate (DHP) solutions to induce calcium phosphate. The resulted calcium phosphate/polyacrylamide/calcium alginate (CP/PAM/CaAlg) hybrid hydrogel membrane was immersed in bovine serum albumin (BSA) aqueous solution for sufficient adsorption. BSA was used as a model protein to investigate the controlled-release behavior of the hybrid hydrogel membranes. The effects of acrylamide/sodium alginate mass ratio, DHP concentration and saline treatment on the swelling behavior and BSA release performance were studied. The morphology of the hydrogel membranes was characterized by scanning electron microscopy (SEM). The results showed that the CP/PAM/CaAlg hybrid hydrogel membranes exhibited a porous structure, which facilitated BSA loading. Meanwhile, the calcium phosphate phase and the hybrid polymer network helped regulate the diffusion pathway of BSA, thereby improving the sustained-release performance. The swelling behavior of the membranes could be regulated by changing the polymer composition and the concentration of DHP. Compared with saline-treated membranes, the phosphate-treated membranes showed better sustained-release performance for BSA in Tris-HCl buffer. The prepared CP/PAM/CaAlg hybrid hydrogel membranes have potential application as protein drug controlled release. Read More

Abstract: This study systematically investigates the laser wire filling welding (LWFW) process of 6061-T6 aluminum alloy lap joints using ER5356 filler wire. The influence of critical process parameters, including laser power, welding speed, and wire feed speed, on weld formation, microstructural evolution, and mechanical properties was evaluated. The results demonstrate that line energy input, determined by laser power and welding speed, is the primary factor governing penetration depth and macroscopic quality. An increase in laser power significantly enhances penetration by stabilizing the keyhole effect, while higher welding speeds refine the Heat-Affected Zone (HAZ) grains by reducing thermal residence time. Microstructural analysis revealed distinct zoning, with fine equiaxed grains in the weld metal (WM) and columnar crystals near the fusion line. The tensile strength of the joints is determined by the synergy between the effective bonding area (penetration depth) and fine-grain strengthening. Under the optimized conditions of 2.8 kW laser power, 25 mm/s welding speed, and 4.0 m/min wire feed speed, high-quality joints with a tensile strength of 195 MPa (approximately 63% of the base metal strength) were obtained. This research provides a theoretical and technical basis for the application of LWFW in automotive aluminum component manufacturing. Read More

Abstract: The growing demand for lightweight yet crashworthy automotive structures has promoted the use of 1.5 GPa grade martensitic steels (MS1500 1). However, laser welding of such ultra high strength materials is challenged by heterogeneous microstructures and severe hydrogen induced delayed cracking (HIDC) risks. This study systematically investigates the laser welding behavior and hydrogen embrittlement susceptibility of MS1500 1, focusing on three aspects: (1) the effect of surface oil contamination (oil free, 1.5 g/m² as received, and 3.0 g/m² excessive lubricant) on microstructural evolution and mechanical performance of laser lap welded (L bend) and butt welded joints; (2) the hydrogen permeation and diffusion behavior in the base metal using electrochemical permeation tests; and (3) the correlation between microstructural features of distinct heat affected subzones, local hardness distribution, and overall joint integrity. Comprehensive microstructural characterization (optical microscopy, scanning electron microscopy, X ray diffraction), mechanical evaluation, and hydrogen permeation measurements reveal that surface oil significantly alters the weld thermal cycle and hydrogen uptake, leading to pronounced softening and increased HIDC susceptibility. The results establish a fundamental understanding of hydrogen trapping characteristics and mechanical reliability of laser welded MS1500 1 joints, providing a scientific basis for mitigating delayed cracking and developing robust welding protocols for ultra high strength steel components in automotive manufacturing. Read More

Abstract: Building energy consumption accounts for approximately 35%–40% of global total energy use, making the improvement of envelope thermal performance a key strategy for building energy efficiency. Thermal insulation mortar has been widely used in building energy renovation due to its convenient construction, relatively low cost, and good compatibility with substrate walls. Although traditional lightweight aggregate thermal insulation mortars (e.g., expanded perlite, glazed hollow beads, EPS particles) can reduce thermal conductivity, they suffer from high water absorption, low compressive strength, drying shrinkage cracking, and insufficient long-term durability, which limit their application in high-performance energy-saving systems. In recent years, research has increasingly shifted toward aerogel-based thermal insulation cementitious composites. Aerogel, featuring a nanoporous structure, ultra-low density, and extremely low thermal conductivity, significantly reduces the thermal conductivity of mortar, enabling lightweight and highly efficient thermal insulation. However, the incorporation of aerogel also leads to a marked decline in mechanical properties, primarily due to the low strength of aerogel itself and the weak interfacial bonding between its hydrophobic surface and the cement paste, which tends to form interfacial transition zone defects and pore-rich regions. To address these challenges, researchers have focused on several aspects, including mix proportion design to balance thermal and mechanical performance by adjusting aerogel content, water-to-binder ratio, and admixtures; interface modification using silane coupling agents, dispersion aids, and low-shear mixing to improve compatibility and dispersion uniformity between aerogel and the cement matrix; fiber reinforcement through the introduction of polypropylene (PP), PVA, basalt and other fibers to bridge cracks, enhance toughness, and compensate for strength loss and cracking tendency; and … Read More

Abstract: This study focuses on Tibetan lamb meat from the Qinghai Tibet Plateau, local sheep meat from Shandong, and goat meat. Using a combination of headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) and headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS), the differences in volatile flavor compound composition and overall flavor profile of the three types of lamb meat were systematically analyzed and compared. Qualitative analysis of flavor compounds was conducted using GC-MS and principal component analysis (PCA) was used to identify the dominant factors affecting flavor differences in different types of lamb meat; Using GC-IMS to obtain fingerprint and two-dimensional differential spectra of volatile substances, achieving intuitive and sensitive differentiation of three types of lamb flavor characteristics. The results showed that GC-MS identified a total of 19 volatile substances, including 8 aldehydes, 5 alcohols, 4 esters, and 2 other compounds. Among them, 16 were detected in Tibetan sheep, 11 in local sheep and 15 in goats. The content of aldehydes such as hexanal and heptanal in Tibetan sheep was significantly higher than that in the other two types of lamb meat; GC-IMS detected a total of 26 volatile compounds, including 8 esters, 6 aldehydes, 9 alcohols and 2 others. Butyl formate and n-hexanol are characteristic flavor compounds of Tibetan sheep, while 2-furanyl methanol acetate is a unique substance of goats. Principal component analysis shows that aldehydes are the core contributing category to the flavor differences among the three types of lamb meat; The HS-GC-IMS fingerprint spectrum intuitively presents the differences in the content and types of three volatile substances in lamb meat.trans-2-Decenal, 1-octen-3-ol, hexanal, 2-heptenal, and nonanal were identified as key volatile compounds through the combination of variable importance in projection (VIP) from PLS-DA and ROAV. The aroma profile radar … Read More

Abstract: Cross-linking reaction flow forming is an advanced technology for preparing hollow fiber hydrogels, featuring simple process, continuous meter-level preparation and 3D structure construction. However, hydrogel sensors made by this method have poor tunability in mechanical and electrical properties, limiting their application. To solve this, this study focuses on the design, preparation, performance testing of heteromorphic lumen hydrogel sensors and their application in flexible sensors. Firstly, an experimental platform for precise extrusion control was built using a coaxial nozzle and microinjection pump system. By adjusting the flow rate of inner-phase calcium chloride (with outer-phase sodium alginate), variable-diameter heteromorphic lumen hydrogels were precisely prepared. A theoretical model based on flow rate regulation was proposed to characterize lumen morphology changes, providing theoretical support for structural optimization. Subsequently, the effects of sodium alginate (3%–5%) and lithium chloride (3%–5%) concentrations on hydrogel properties were explored. Results show that higher sodium alginate concentration improves tensile strength, elongation at break and fatigue resistance, while electrical properties first rise then fall. Higher lithium chloride concentration reduces mechanical properties but enhances electrical conductivity (with significant strain-dependent changes). The optimal formulation (3.75% sodium alginate, 5% lithium chloride) achieves 65 kPa maximum stress and 33.86 S/m maximum conductivity. In summary, this study realized precise regulation and performance optimization of hydrogel sensors via heteromorphic lumen design. Flow rate adjustment and concentration optimization are crucial for improving their mechanical, electrical and sensing properties, providing theoretical and practical support for their application in high-precision biological signal monitoring and flexible electronics. Read More