Search Results (1,084)

As a promising member of the carbon nitride family, nitrogen-rich g-C₃N₅ has attracted significant attention because of its excellent light absorption performance. Nevertheless, its practical application in photocatalytic CO₂ reduction is hindered by severe photogenerated charge recombination and limited CO₂ adsorption capacity. Constructing a heterojunction has emerged as an effective strategy to mitigate charge recombination, thereby enhancing the photocatalytic performance of the catalyst. Herein, a series of CdS/g-C₃N₅-X heterojunction catalysts were prepared via an in situ hydrothermal approach. The obtained heterojunction catalysts exhibited a novel coral reef-like morphology which facilitated the exposure of additional active sites, thereby enhancing the adsorption and activation of CO₂. Moreover, studies have shown that CdS can be anchored to the surface of g-C₃N₅ through C-S bonds, forming a built-in electric field at the interface, which accelerated the separation and transfer of photogenerated charges. Consequently, the resulting heterojunction materials demonstrated high efficiency in photocatalytic CO₂ reduction with H₂O as a sacrificial agent. In particular, CdS/g-C₃N₅-0.2 exhibited the maximum photocatalytic performance up to 22.9 μmol·g⁻¹·h⁻¹, which was 6 times and 3 times that of unmodified g-C₃N₅ and CdS, respectively. The results indicated that the increased active sites and enhanced charge separation of the Cd/g-C₃N₅-0.2 catalyst were the primary reasons for its improved photocatalytic CO₂ reduction performance. This work provides a novel heterojunction-based photocatalyst for efficient CO₂ photocatalytic reduction, offering insights into the preparation of high-performance photocatalysts for sustainable energy applications. Full article

The porous structure, in which many pores are intentionally placed inside the material, has excellent impact energy absorption properties. Recent studies have attempted to fabricate multi-layered porous structures with different mechanical properties within a single porous structure sample, and the mechanical properties of these structures are being elucidated. However, these studies mainly attempted to vary the densities, pore structures, and alloy compositions within a single material, such as aluminum, for the entire sample. Since multi-materials are now being promoted to utilize the most suitable material type in the right place, porous structures made of different materials, such as a combination of aluminum and resin, are expected to be required in the future. In this study, we attempted to fabricate two-layered porous structure samples of different materials by printing a resin porous structure using a 3D printer on an aluminum foam fabricated by a precursor foaming process. Static compression tests were performed on the resulting two-layered porous structure samples to investigate their mechanical properties. The resin porous structure printed by the 3D printer and the aluminum foam were both designed to expose the porous structure on the surface of the specimen so that the deformation behavior can be easily observed. The density of the resin porous structure was varied by systematically varying the filling rate of the resin porous structure to be printed, and the effect on the compression properties was investigated. The fabricated two-layered porous structure was effectively bonded between the two layers by the anchor effect, which is a mechanical bonding caused by the resin penetrating into the pores. The layers exhibited robust bonding with no evidence of separation. It was possible to fabricate a two-layered porous structure that exhibited both properties of aluminum foam and those of resin porous structure. It was found that the plateau stress in the resin porous structure layer can be controlled between about 0.5 MPa and 40 MPa, and the deformation behavior and energy absorption properties of the two-layered porous structure can be controlled by varying the resin filling rate of the resin porous structure layer. That is, it was indicated that multi-layered porous structures with various densities and consisting of various types of materials allow for the optimal design of porous structures used in structural materials. Full article

The immobilization of enzymes in polyamide-based polymeric materials through covalent bonding is an established technique to stabilize and reuse biocatalysts in industrial processes. Traditionally, enzymes are immobilized using crosslinking agents that activate functional groups on both the support and the enzyme, creating strong bonds that securely anchor the enzyme to the surface. While effective for maintaining enzyme activity over multiple cycles, this method can reduce catalytic efficiency due to rigid binding and involves complex activation steps. Recently, in situ immobilization approaches have emerged as promising alternatives. In this method, enzymes are directly entrapped within the polymer matrix during the synthesis of the polyamide support, such as nylon, simplifying the process and offering enhanced control over enzyme distribution. For instance, studies have demonstrated that in situ immobilization can improve enzyme stability by protecting it within the polymeric network, while reducing production costs and waste. This review explores the ability of polyamide as a support material for immobilization of enzymes, analyzing key techniques, performance across applications, and future strategies to optimize polymer-enzyme interactions for industrial use. Full article

This paper presents an enhanced Faster R-CNN model for detecting surface defects in resistance welding spots, improving both efficiency and accuracy for body-in-white quality monitoring. Key innovations include using high-confidence anchor boxes from the RPN network to locate welding spots, using the SmoothL1 loss function, and applying Fast R-CNN to classify detected defects. Additionally, a new pruning model is introduced, reducing unnecessary layers and parameters in the neural network, leading to faster processing times without sacrificing accuracy. Tests show that the model achieves over 90% accuracy and recall, processing each image in about 15 ms, meeting industrial requirements for welding spot inspection. Full article

Lactococcus lactis is a potential bacterial cell factory to develop delivery systems for vaccines and therapeutic proteins. Much progress has been made in applications using engineered L. lactis against, e.g., inflammatory bowel disease and cervical cancer, but the improvement of secretion and cell anchoring efficacy is still desirable. A double-labeling method based on biarsenical hairpin binding and nickel–polyhistidine affinity was used for visualization of protein trafficking and the quantification of targeted proteins on the cell surface and in the cytoplasm. To investigate the importance of mature domain targeting signals (MTSs), we generated truncated constructs encoding 126, 66, and 26 amino acid residues from the N-terminus of the basic membrane protein A (BmpA) and fused those with the gene for the human papillomavirus serotype 16 (HPV16) E7 oncoprotein. Overexpression of fusion proteins was observed to come at the cost of cell proliferation. L. lactis cells produced and displayed the shortest fusion protein only with difficulty, suggesting that the entire absence of a homologous sequence containing MTSs significantly impedes the export and surface anchoring of fusion proteins. With 40 amino acids following the signal peptide and containing one MTS, effective translocation was possible. Mutations of MTSs towards increased hydrophobicity resulted in increased secreted and surface-displayed fusion protein, suggesting the potential to design rationally improved constructs. Full article

Properties of surface anchoring depend on the absorbed exposure energy and various potential interactions associated with liquid crystal and azo dye layers. In this study, we investigate a model of dispersion, steric and photoinduced interactions with the goal of providing a qualitative and quantitative description of orientationally ordered hard uniaxial liquid crystals and azo dye molecules. By using the Onsager theory, we estimated the effect of excluded volume. Typical repulsive potentials between liquid crystal and azo dye molecules are displayed graphically. The presence of statistical dispersion in molecular alignment of liquid crystals leads to potential wells in dipole–dipole interactions. Our mean field theory investigation of dipole–dipole interactions shows that the anchoring free energy is governed by the net interaction energy associated with the averaged dipole moments of liquid crystal and azo dye molecules, photoaligned surface dipole moments, and local charge densities. We also use the Fokker–Planck equation to show that rotational diffusion is described by the effective mean field potential, which includes photoinduced and van der Waals interactions. Our findings underscore the potential of mean field theory for intermolecular couplings in photoaligned surfaces, opening up new pathways of molecular design for a broad range of parameters. Full article

The effect of solution pH on the formation and surface structure of 2-pyrazinethiolate (2-PyzS) self-assembled monolayers (SAMs) formed by the adsorption of 2-mercaptopyrazine (2-PyzSH) on Au(111) was investigated using scanning tunneling microscopy (STM) and X-ray photoelectron microscopy (XPS). Molecular-scale STM observations clearly revealed that 2-PyzS SAMs at pH 2 had a short-range ordered phase of (2√3 × √21)R30° structure with a standing-up adsorption structure. However, 2-PyzS SAMs at pH 8 had a very unique long-range ordered phase, showing a “ladder-like molecular arrangement” with bright repeating rows. This ordered phase was assigned to the (3 × √37)R43° structure, consisting of two different adsorption structures: standing-up and tilted adsorption structures. The average arial density of 2-PyzS SAMs on Au(111) at pH 8 was calculated to be 49.47 Ų/molecule, which is 1.52 times more loosely packed compared to the SAMs at pH 2 with 32.55 Ų/molecule. XPS measurements showed that 2-PyzS SAMs at pH 2 and pH 8 were mainly formed through chemical interactions between the sulfur anchoring group and the Au(111) substrates. The proposed structural models of packing structures for 2-PyzS SAMs on Au(111) at different pHs are well supported by the XPS results. The results of this study will provide new insights into the formation, surface structure, and molecular orientation of SAMs by N-heteroaromatic thiols with pyrazine molecular backbone on Au(111) at the molecular level. Full article

Flexible perovskite solar cells (F-PSCs) hold great potential for lightweight photovoltaic applications due to their flexibility, bending compatibility, and low manufacturing cost. However, tin oxide (SnO₂), as a common electron transport layer (ETL) used in F-PSCs, typically suffers from high-density surface defects that hinder the charge extraction efficiency and deteriorate the crystallization quality of the upper perovskite film. Additionally, the poor buried interface quality intensifies lattice extrusion and strain residue across the perovskite films, further aggravating the mechanical brittleness in devices. To address the issues, we developed a molecular bridging strategy by introducing the 2,2′-oxybis(ethylenediamine) dihydrochloride (DO) at the perovskite/SnO₂ interface. The diammonium groups of spacer ligands can achieve the bidentate anchoring on the SnO₂ and perovskite films, cooperating with the oxygen atom on the alkyl chain to passivate the charged defects at the buried interface. The tailored interface properties also endow the optimized crystallization quality of perovskite films and significantly alleviate tensile strain to strengthen the perovskite’s pliability. As a result, the F-PSCs achieved a champion efficiency of 23.50%, outperforming the value of 21.87% for the control device. Furthermore, the devices exhibited excellent mechanical robustness, maintaining 90% of the initial PCE after 6000 bending cycles at a radius of 4 mm. This work presents a reliable strategy for the synergistic optimization of the buried contact at the electron extraction interface, contributing to the further development of efficient and stable F-PSCs. Full article

This study addresses the critical challenge of carbon corrosion in proton exchange membrane fuel cells (PEMFCs) by developing hybrid supports that combine the high surface area of carbon black (CB) with the superior crystallinity and graphitic structure of carbon nanofibers (CNFs). Two commercially available CB samples were physically activated and composited with two types of CNFs synthesized via chemical vapor deposition using different carbon sources. The structure, morphology, and crystallinity of the resulting CNF–CB hybrid supports were characterized, and the performances of these hybrid supports in mitigating carbon corrosion and enhancing the PEMFC performance was evaluated through full-cell testing in collaboration with a membrane electrode assembly (MEA) manufacturer (VinaTech, Seoul, Republic, of Korea), adhering to industry-standard fabrication and evaluation procedures. Accelerated stress tests following the US Department of Energy protocols revealed that incorporating CNFs enhanced the durability of the CB-based hybrid supports without compromising their performance. The improved performance of the MEAs with the hybrid carbon support is attributed to the ability of the CNF to act as a structural backbone, facilitate water removal, and provide abundant edge plane sites for anchoring the platinum catalyst, which promoted the oxygen reduction reaction and improved catalyst utilization. The findings of this study highlight the potential of CNF-reinforced CB supports for enhancing the durability and performance of PEMFCs. Full article

Background/Objectives: African swine fever (ASF), caused by African swine fever virus (ASFV), poses a significant threat to the global swine industry. This underscores the urgent need for safe and effective ASF vaccines. Methods: Here, we constructed five bacterium-like particles (BLPs) that each display one of the five ASFV antigens (F317L, H171R, D117L, B602L, and p54) based on the Gram-positive enhancer matrix-protein anchor (GEM-PA) system. GEM is a bacterial particle that contains only peptidoglycan, while PA is composed of three lysin motifs (Lysm) derived from the C-terminus of the AcmA protein, capable of non-covalently binding to GEM. By fusing the ASFV antigens with PA, the ASFV antigens can be firmly attached to the surface of GEM. Subsequently, the piglets were immunized via intramuscular injection with a mixture of BLPs-F317L, BLPs-H171R, BLPs-D117L, BLPs-B602L, and BLPs-p54. Results: The results showed that the piglets developed detectable serum IgG antibodies 2 weeks after the first immunization, and these high antibody levels were maintained 4 weeks after the booster immunization. Moreover, these piglets produced more IFN-γ-producing lymphocytes than the control piglets. Conclusions: The data indicate that the generated BLPs mixture can stimulate both humoral and cellular immune responses in piglets, these five ASFV proteins are promising antigens, and the BLPs generated represent candidate ASF vaccines. Full article

To address the limitations of existing deep learning-based algorithms in detecting surface defects on brake pipe ends, a novel lightweight detection algorithm, FP-YOLOv8, is proposed. This algorithm is developed based on the YOLOv8n framework with the aim of improving accuracy and model lightweight design. First, the C2f_GhostV2 module has been designed to replace the original C2f module. It reduces the model’s parameter count through its unique design. It achieves improved feature representation by adopting specific technique within its structure. Additionally, it incorporates the decoupled fully connected (DFC) attention mechanism, which minimizes information loss during long-range feature transmission by separately capturing pixel information along horizontal and vertical axes via convolution. Second, the Dynamic ATSS label allocation strategy is applied, which dynamically adjusts label assignments by integrating Anchor IoUs and predicted IoUs, effectively reducing the misclassification of high-quality prediction samples as negative samples. Thus, it improves the detection accuracy of the model. Lastly, an asymmetric small-target detection head, FADH, is proposed to utilize depth-separable convolution to accomplish classification and regression tasks, enabling more precise capture of detailed information across scales and improving the detection of small-target defects. The experimental results show that FP-YOLOv8 achieves a mAP50 of 89.5% and an F1-score of 87% on the ends surface defects dataset, representing improvements of 3.3% and 6.0%, respectively, over the YOLOv8n algorithm, Meanwhile, it reduces model parameters and computational costs by 14.3% and 21.0%. Additionally, compared to the baseline model, the AP50 values for cracks, scratches, and flash defects rise by 5.5%, 5.6%, and 2.3%, respectively. These results validate the efficacy of FP-YOLOv8 in enhancing defect detection accuracy, reducing missed detection rates, and decreasing model parameter counts and computational demands, thus meeting the requirements of online defect detection for brake pipe ends surfaces. Full article

Bgl2p is a major, conservative, constitutive glucanosyltransglycosylase of the yeast cell wall (CW) with amyloid amino acid sequences, strongly non-covalently anchored in CW, but is able to leave it. In the environment, Bgl2p can form fibrils and/or participate in biofilm formation. Despite a long study, the question of how Bgl2p is anchored in CW remains unclear. Earlier, it was demonstrated that Bgl2p lost the ability to attach in CW and to fibrillate after the deletion of nine amino acids in its C-terminal region (CTR). Here, we demonstrated that a Bgl2p anchoring is weakened by substitution Glu-233/Ala in the active center. Using AlphaFold and molecular modeling approach, we demonstrated the role of CTR on Bgl2p attachment and supposed the conformational possibilities determined by the presence or absence of an intramolecular disulfide bond, forming by Cys-310, leading to accessibility of amyloid sequence and β-turns localized in CTR of Bgl2p for protein interactions. We hypothesized the mode of Bgl2p attachment in CW. Using atomic force microscopy, we investigated fibrillar structures formed by peptide V187MANAFSYWQ196 and suggested that it can serve as a factor leading to the induction of amyloid formation during interaction of Bgl2p with other proteins and is of medical interest being located close to the surface of the molecule. Full article

We report the design and development of a novel multifunctional nanostructure, RB-AuSiO₂_HSA-DOX, where tri-modal cancer treatment strategies—photothermal therapy (PTT), photodynamic therapy (PDT), chemotherapy—luminescent properties and targeting are integrated into the same scaffold. It consists of a gold core with optical and thermo-plasmonic properties and is covered by a silica shell entrapping a well-known photosensitizer and luminophore, Rose Bengal (RB). The nanoparticle surface was decorated with Human Serum Albumin (HSA) through a covalent conjugation to confer its targeting abilities and as a carrier of Doxorubicin (DOX), one of the most effective anticancer drugs in clinical chemotherapy. The obtained nanostructure was fully characterized through transmission electron microscopy (TEM), dynamic light scattering (DLS) and UV-visible spectroscopy, with a homogeneous and spherical shape, an average diameter of about 60 nm and negative ζ-potential value Singlet oxygen generation and photothermal properties were explored under green light irradiation. The interaction between DOX-HSA anchored on the nanoplatform was investigated by fluorescence spectroscopy and compared to that of DOX-HSA, pointing out different accessibility of the drug molecules to the HSA binding sites, whether the protein is free or bound to the nanoparticle surface. To the best of our knowledge, there are no studies comparing a drug–HSA interaction with that of the same protein anchored to nanoparticles. Furthermore, the uptake of RB-AuSiO₂_HSA-DOX into MDA-MB-231 mammary cells was assessed by confocal imaging, highlighting—at early time of incubation and as demonstrated by the increased DOX luminescence displayed within cells—a better internalization of the carried anticancer drug compared to the free one, making the obtained nanostructure a suitable and promising platform for an anticancer multimodal approach. Full article

The shear-yielding bolt is a new type of anchoring structure, and its working mechanism in layered rocks is not yet well understood. To investigate its transverse shear characteristics, this paper takes the shear-yielding bolt as the research subject and uses different anchoring states of bolts as variables. A comparative study of shear-yielding bolts and traditional bolts is conducted using the Abaqus numerical simulation software and large-scale direct shear tests. The results show that (1) low-modulus material allows a slight displacement between the structural surface layers, which exerts the friction strength between rock mass layers and avoids stress concentration on the bolt. The shear-yielding bolts reach their peak shear stress in the case of greater displacement, averagely increased by 40% compared to traditional anchor bolts. (2) An increase in the moisture content has less influence on the shear-yielding bolt owing to the material properties. When the moisture content of the structural surface rises from 12% to 20%, for cases where the shear-yielding bolts are used, the peak shear stress decreases by 0.12 kPa, which only accounts for 12% of the original strength. (3) There is an optimum thickness of the low-modulus material in the shear-yielding bolt, considering its effect of releasing shear and the bonding effect between it and the bolt. According to the test results and numerical analysis, the optimum thickness is 15 mm. The results of this research provide a reference and basis for future study and engineering applications of shear-yielding bolts. Full article

The interaction of Ni with (6,0) and (8,0) zigzag carbon nanotube exterior surfaces containing two vacancies was studied using density functional theory (DFT). A two-vacancy defect was analysed in order to anchor Ni, and the pristine nanotube was also considered as a reference for each chirality. The adsorbed Ni stability and the nanotube’s geometry and electronic structure were analysed before and after the adsorption. We compared calculations performed using a general gradient functional with those conducted using two semi-classical dispersion methods to assess the van der Waals forces (PBE-D2 and PBE-D3). In addition, the inclusion of the Hubbard parameter for the correction of Ni d electron self-interaction energy was included, and we evaluated energy and electronic structure changes through atomic-level calculations. Adsorption energy, the density of states, and the charge distribution were obtained to establish the Ni binding on the defective nanotube’s dominating mechanisms. The effect of curvature and applied functional influence was also considered. Furthermore, a bonding analysis was performed to complement our comprehension of the interaction between Ni and the nanotube surfaces. The electronic results show that Ni-doped two-vacancy (6,0) and (8,0) carbon nanotubes can be applied for the development of low-resistance contact materials and spintronic devices, respectively. Full article