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Selective hydrogenation of fatty acids/esters is an efficient way to produce fatty alcohols, and it is very promising to provide in situ H2generated via aqueous phase reforming of hydrogen donors. Here, the supported Ni–In intermetallic compounds (IMCs) were prepared for in situ aqueous phase hydrogenation of methyl palmitate to hexadecanol using methanol as a hydrogen donor. First, the effects of Ni/In atomic ratio and metal loading on the performance of ZrO2-supported Ni–In IMCs were investigated. Different from metallic Ni that favors decarbonylation/decarboxylation generating n-pentadecane, all of the Ni2In, NiIn, and Ni2In3IMCs facilitate the selective hydrogenation to yield hexadecanol. Therein, the ZrO2-supported NiIn IMC with a total metal loading of 40 wt % gives the best performance with a hexadecanol yield of 87.6%. Second, the performance of Ni–In IMCs on different supports [ZrO2, TiO2, Al2O3, SiO2, and activated carbon (AC)] was compared. ZrO2- and TiO2-supported NiIn IMC (especially TiO2) show higher stability than others. This is ascribed to their higher hydrothermal stability and interaction with the NiIn IMC, restraining the sintering and leaching of the NiIn IMC. During the four times recycling, the hexadecanol yield maintains ∼80% on the TiO2-supported NiIn IMC, while it slightly decreases from 87.6% to ∼83% on the ZrO2-supported NiIn IMC, the slight deactivation of which is due to carbon deposition. In contrast, Al2O3is converted to boehmite under a hydrothermal condition, and there is remarkable leaching of Ni and In species from SiO2and AC, all of which are detrimental to the catalyst stability.

Surface-imprinted polymers (ZIF-67@MIPs) supported by ZIF-67 were prepared by precipitation polymerization using enrofloxacin (ENR) as the template molecule, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. ZIF-67@MIPs were characterized by Fourier transform infrared spectrometry, X-ray diffraction, scanning electron microscopy, and particle size distribution. The adsorption performance of the polymer was studied. The adsorption equilibrium was reached within 30 min. The maximum adsorption was 9.02 μg·mg–1. The imprinting factor was 2.58. The polymer was then used as a sorbent of a solid-phase extraction column for the separation and purification of ENR in real water samples. The extraction conditions were optimized. The method was established by high-performance liquid chromatography, and the linearity was verified by UPLC-MSMS. The correlation coefficient and limits of detection and quantification were 0.9999, 0.23 ng·mL–1, and 0.76 ng·mL–1, respectively. The recoveries were in the range of 83.79–100.68%; the relative standard deviation was 4.46–7.35%. The above data indicated that the method could be used for the separation and enrichment of ENR in real samples.

Adjuvants for vaccines with characteristics of improving adaptive immunity particularly via leverage of antigen presenting cells (APCs) are currently lacking. In a previous work we obtained a new soluble 300 kDa homogeneous β-glucan named GFPBW1 from the fruit bodies of Granola frondosa. GFPBW1 could activate macrophages by targeting dendritic cell associated C-type lectin 1 (Dectin-1)/Syk/NF-κB signaling to achieve antitumour effects. In this study the adjuvant effects of GFPBW1 were explored with OVA-antigen and B16-OVA tumor model. We showed that GFPBW1 (5, 50, 500 μg/mL) dose-dependently promoted activation and maturation of APCs in vitro by increasing CD80, CD86 and MHC II expression. We immunized female mice with OVA in combination with GFPBW1 (50 or 300 μg) twice with an interval of two weeks. GFPBW1 markedly and dose-dependently increased OVA-specific antibody titers of different subtypes including IgG1, IgG2a, IgG2b and IgG3, suggesting that it could serve as an adjuvant for both Th1 and Th2 type immune responses. Furthermore, GFPBW1 in combination with aluminum significantly increased the titers of OVA-specific IgG2a and IgG2b, but not those of IgG1, suggesting that GFPBW1 could be used as a co-adjuvant of aluminum to compensate for Th1 deficiency. For mice immunized with OVA plus GFPBW1, no obvious pathological injury was observed in either major organs or injection sites, and no abnormalities were noted for any of the hematological parameters. When GFPBW1 served as an adjuvant in the B16-OVA cancer vaccine models, it could accomplish entire tumor suppression with preventive vaccines, and enhance antitumour efficacy with therapeutic vaccines. Differentially expressed genes were found to be enriched in antigen processing process, specifically increased tumor infiltration of DCs, B1 cells and plasma cells in the OVA plus GFPBW1 group, in accordance with its activation and maturation function of APCs. Collectively, this study systematically describes the properties of GFPBW1 as a novel potent and safe adjuvant and highlights its great potential in vaccine development.

Allergic enteritis is an important phenotype of food allergies. However, there is not a suitable animal model for deeply exploring the natural progression and mechanism of allergic enteritis. In our study, we successfully developed an allergic enteritis animal model by feeding mice with an egg white diet. Following the dietary challenge, allergic mice displayed typical food allergy manifestations, including decreased core temperature, aversion to the allergenic diet, and elevated levels of serum sIgE and mMCP-1. Notably, these dietary challenged mice exhibited severe gut damage, characterized by disrupted intestinal microstructure, tissue inflammation, and edema that were evident morphologically. Moreover, upon exposure to food allergens, we observed a marked increase in caspase-3 and GSDMC levels in allergic mice. These two active proteins were found to be colocalized in damaged mucosal enterocytes and were associated with the secretion of epithelial sourced alarmins, such as IL25 and TSLP. Further data on the cellular and molecular levels suggest that such severe food-induced enteritis is mediated by the caspase-3-GSDMC pathway. We believe that this established animal model provides a valuable tool for advancing research on the mechanisms of food allergies.

The tethered molecule exhibits characteristics of both free and fixed states, with the electrodynamics involved in its diffusion, electrophoresis, and stretching processes still not fully understood. We developed a Single-Molecule Manipulation, Identification, and Length Examination (SMILE) system by integrating piezoelectric devices with nanopipettes. This system enabled successful capture and stretching of tethered double-stranded DNA within the nanopore. Our research unveiled distinct capture (rcapture) and stretch radii (rstretch) surrounding the DNA’s anchor point. Notably, consistent ratios of capture radius for DNA of varying lengths (2k, 4k, and 6k base pairs) were observed across different capturing voltages, approximately 1:1.4:1.83, showing a resemblance to their gyration radius ratios. However, the ratios of stretch radius are consistent to their contour length (L0), with the stretching ratio (rstretch/L0) increasing from 70 to 90% as the voltage rose from 100 to 1000 mV. Additionally, through numerical simulations, we identified the origin of capture and stretch radii, determined by the entropic elasticity-induced capture barrier and the electric field-dominant escape barrier. This research introduces an innovative methodology and outlines research perspectives for a comprehensive exploration of the conformational, electrical, and diffusion characteristics of tethered molecules.

The cascaded-H-bridge (CHB) type converter is widely used in grid-tied applications, such as static var generator (SVG), static synchronous compensator (STATCOM), and photovoltaic system. In these situations, the dc-link capacitor is a key component, which serves as energy buffer and determines the quality of output waveform. Thus, acquiring the health status of these capacitors is critical for the reliable operation of the whole system. In this article, a general capacitor condition monitoring approach based on improved recursive least square (RLS) for CHB-type converters is proposed. The key equations are deduced from the basic control strategies and no extra sensors are introduced. The only signal required is the dc-link voltage, which is already collected for control purpose. The RLS algorithm is modified by adding self-adapted forgetting factor, to achieve a good performance on both identification accuracy and tracking speed. The capacitance estimation error is below 1%, and shows good feasibility in various working conditions and applications. The principle, main steps, case study, and proof-of-concept of the proposed method are presented.

Cascaded H-Bridge (CHB) grid-connected converters face challenges during startup, including issues such as overmodulation and inrush currents due to low dc-link voltage. In addition, the common occurrence of dc-link voltage imbalance among multiple independent submodules (SMs) of CHB exacerbates these risks. In this article, a self-excitation startup strategy based on dynamic virtual impedance is proposed, adjusting the converter's output impedance to a virtual impedance. By establishing a relationship between the modulation index and virtual impedance, the modulation index is controlled within the linear modulation range, effectively suppressing inrush currents. The design of the modulation index reduces power loss during startup and enhances the charging power of the converter, allowing the converter to complete startup within a predetermined time. Furthermore, for typical control-based methods of dc-link voltage balance, a quantitative analysis of the impact of modulation index on the range of SM active power modification is conducted to optimize the modulation index design, thereby improving the dc-link voltage balance capability during the startup. Simulation and experimental results are presented to validate the effectiveness of the proposed method.

The rise of the Internet of Things has spurred the growth of wireless applications, particularly Wi-Fi-based indoor localization, which is gaining prominence owing to its cost-effectiveness. Nevertheless, the accuracy of Wi-Fi-based indoor localization is hindered by signal instability. To address this limitation, we introduce an interval random analysis approach for uncertain Wi-Fi-based indoor localization. Specifically, this approach employs an interval random parameter lognormal shadowing model for radio map enhancement and adaptive Bayesian comprehensive learning (IRPLS-ABCL) particle swarm optimization (PSO) for location estimation accuracy enhancement. The process comprises two stages: offline training and online localization. During the offline phase, we establish the interval random parameter lognormal shadowing model, considering the parameters as interval random variables, rather than precise values, in a sparse reference point scenario. In the online phase, we use a double-panel fingerprint homogeneity model to assess fingerprint similarity and apply the adaptive Bayesian comprehensive learning PSO algorithm to enhance localization precision. The experimental results show that the proposed algorithm can achieve the best performance in terms of localization accuracy based on the predicted average received signal strength (RSS), reaching 1.89 m.

Metastatic rhabdomyosarcoma is associated with poor survival and unsatisfactory treatment outcomes. Therefore, new immunotherapeutic methods are urgently required. Fibroblast growth factor receptor 4 (FGFR4), a new therapeutic target for rhabdomyosarcoma, plays a crucial role in its onset and development. This study aimed to generate FGFR4 single-chain variable fragment-based chimeric antigen receptor (CAR) T cells without causing evident toxicity and incorporating an inducible caspase-9 (iCasp9) suicide gene system to enhance their safety. FGFR4 antigen expression was evaluated in normal murine tissues, normal human tissues, and specimens from patients with rhabdomyosarcoma. Combined with a 4-1BB co-stimulatory domain, a CD3ζ signaling domain, and an iCasp9 suicide gene, CAR-T cells with an FGFR4-specific single-chain variable fragment were developed. The specific cytotoxic effects, T-cell proliferation, cytokine secretion, apoptosis induction by chemical dimerization (AP20187), and toxicity of FGFR4 CAR-T cells were investigated in vitro and in vivo. FGFR4 CAR-T cells generated a variety of immune-promoting cytokines, including tumor necrosis factor α, interleukin 2, and interferon γ, and displayed effective cytotoxic activity against FGFR4-overexpressing rhabdomyosarcoma cells in vitro. FGFR4 CAR-T cells were relatively effective against FGFR4-overexpressing rhabdomyosarcoma, with tumor regression and poor survival in a subcutaneous xenograft model. The iCasp9 gene was incorporated into FGFR4 CAR-T cells and it was demonstrated that effective and reliable suicide gene activity depends on the administration of AP20187. By making use of the cross-reaction of FGFR4 CAR-T cells with murine FGFR4 in a syngeneic tumor model, this study found that FGFR4 CAR-T cells could regulate the growth of tumors without evident toxicity. Our study demonstrates that FGFR4 is a prospective target for CAR-T cell therapy in rhabdomyosarcoma without serious on-target off-tumor toxicity. FGFR4 CAR-T cells with the iCasp9 suicide gene system as a safety switch to limit toxicity may broaden the clinical applications of cellular therapy.

Two-dimensional (2D) antiferromagnetic (AFM) skyrmions are free from stray magnetic field and skyrmion Hall effect, and can be driven by a small current density up to a high speed, desirable for low-power spintronic applications. However, most 2D AFM skyrmions are realized in complex heterostructured materials, which impedes the dense integration of spintronic devices. Here, we propose that 2D AFM skyrmions can be achieved in ruthenium tetrafluoride (RuF4) monolayer using hybrid functional theory combined with atomistic spin dynamics simulations. Our study indicates that 2D RuF4is dynamically stable and its nondegenerate vibration modes in optical branches are either Raman or infrared active. Furthermore, 2D RuF4acts as an indirect bandgap semiconductor with an out-of-plane AFM state. Notably, the presence of a weak Dzyaloshinskii-Moriya interaction in 2D RuF4leads to a spin spiral ground state at low temperatures, enabling the formation of AFM skyrmions with possible length modulation by an external magnetic field. Our results give insight into 2D RuF4and may provide an intriguing platform for 2D AFM skyrmion-based spintronic applications.

The grid-forming (GFM) converter has excellent active support capabilities, but it will face problems of transient instability and transient overcurrent during grid faults, which brings challenges to its large-scale application. Aiming at this problem, in this article, we analyze the transient instability mechanism and the transient overcurrent causes of the GFM converter. The analysis results show that active power imbalance is the essential reason that drives the power angle to increase and even causes transient instability, and the increase in power angle and the approximately constant internal potential cause the converter to generate transient overcurrent. Based on the above analysis, an active power and voltage cooperative control strategy is proposed to improve the fault ride-through capability of the GFM converter. This strategy consists of transient active power control and transient voltage control, which can eliminate the active power imbalance and flexibly regulate the internal potential according to the fault current, thus ensuring the transient stable operation of the converter while suppressing transient overcurrent. More importantly, the proposed control strategy is not affected by the fault degree and fault duration. Simulation and experimental results verify the effectiveness of the proposed strategy.

• Porous Ti 3 SiC 2 scaffolds with a porosity of 62.9 % exhibit superior compressive strength ∼68.12 MPa. • The apatite mineralization of Ti 3 SiC 2 scaffolds induces polarization of RAW264.7 cells from M1 to M2 phenotype, and promotes the differentiation of MC3T3-E1 cells. • The osteointegration and osteogenic functions of Ti 3 SiC 2 scaffolds can be improved via in-situ biomineralization after implantation. • Porous Ti 3 SiC 2 ceramics with superior mechanical strength and biological functions are likely used as bone implants for load or minor-load bearing conditions. Ti 3 SiC 2 ceramics exhibit excellent mechanical properties and good biocompatibility, rendering them promising bone substitutes for load-bearing conditions. However, the bone integration and osteogenic ability of Ti 3 SiC 2 ceramics remain unclear. Herein, porous Ti 3 SiC 2 ceramics were prepared and systematically investigated as bone scaffolds. The Ti 3 SiC 2 scaffolds with a porosity of 62.9 % ± 2.5 % showed high compressive strength ∼68.12 ± 4.33 MPa. Silicon hydroxyl groups formed on the surface of Ti 3 SiC 2 after soaking in simulated body fluid, which played a critical role in the apatite mineralization of the scaffolds. Biomineralization of Ti 3 SiC 2 scaffolds was found when implanted subcutaneously in the rat dorsum for 2 weeks, demonstrating good osteogenesis ability. The apatite mineralization of the Ti 3 SiC 2 scaffold facilitated the polarization of RAW264.7 cells from M1 to M2 phenotype, which also promoted the differentiation of MC3T3-E1 cells. The porous Ti 3 SiC 2 scaffolds improved osteointegration and bone regeneration after implantation in rabbit femoral defects. Impressively, the number of the newly formed trabeculae in the Ti 3 SiC 2 group was three times of the control group after implantation for 8 weeks, showing excellent bone defect repair. This work demonstrates that Ti 3 SiC 2 implants with improved biological functions likely via in-situ biomineralization are promising candidates for bone regeneration. [Display omitted] [ABSTRACT FROM AUTHOR]

Dietary factors have been associated with an increased prevalence of food allergy (FA). However, little is known about how an unhealthy diet in early life affects FA reactions in offspring. The objective of this study is to provide a scientific foundation for developing and promoting healthy dietary patterns in early life. In this study, we found that maternal high-fat diet (HFD) during pregnancy and lactation exacerbates FA (HFD-FA) in offspring mice, leading to increased serum levels of mast cell protease 1. First, we studied the systemic immunity of the HFD-FA mice and observed elevated levels of proinflammatory cytokines (IL-4, IL-6, and IL-1β) and a reduced frequency of Treg cells in splenocytes. Additionally, the HFD-FA mice showed increased gut permeability, accumulation of intestinal mast cells, and a decrease in the Treg cell frequency in the mesenteric lymph nodes. Furthermore, our findings also indicated a reduction in gut microbial diversity and abundance in HFD-FA mice. Importantly, lipid metabolism profiling revealed unique lipid profiles in the HFD-FA mice, with significant upregulation of triglycerides and downregulation of sphingolipids. Taken together, our results suggest that maternal HFD alters intestinal homeostasis and increases FA susceptibility in offspring mice.

A palladium-catalyzed [4 + 1] annulation of N-arylimidoyl chlorides with β-keto esters has been developed. In the presence of Pd(OAc)2, PCy3, and K3PO4, a variety of fluoalkyl-containing N-arylimidoyl chlorides smoothly underwent the cascade C–H imidoylation/deacylative Heck-type reactions to afford biologically important 2-fluoroalkyl indoles in moderate to good yields.

The node upset may occur in the memory cell if the charged particle from cosmos rays or packaging materials strikes the integrated circuit. Radiation-hardened-by-design (RHBD) techniques introduce redundant transistors in the SRAM cell to improve its ability of recovering from the undesired node upset. However, the extra redundant transistors may increase the number of sensitive nodes in the SRAM cell, which decreases its capability of node-upset tolerance in turn. This work proposes an RHBD 14T SRAM cell and an RHBD 16T SRAM cell. Both the proposed SRAM cells only have two sensitive nodes. The proposed SRAM cells are able to recover from all the SNU cases. The layout harden technique is used to protect the proposed cells from SEMNU, and the blank of the hardened layout is reused so the proposed 14T and 16T SRAM cells consume the same area. Although the proposed cells have more transistors, the hardened layout areas of NS-10T/ PS-10T/ RHD-12T/ RHBD-10T/ RHBD-10T[VLSI]/ QUCCE-12T are respectively $1.78\times $ / $1.78\times $ / $1.83\times $ / $1.78\times $ / $1.78\times $ / $1.99\times $ larger than that of the proposed cells. The reason is that the layout harden technique is easier to be applied to the proposed cells because they only have two sensitive nodes.

Grid-connected inverters (GCIs) operating in grid-following (GFL) mode may be unstable under weak grids with low short-circuit ratio (SCR). Improved GFL controls enhance the small-signal stability of GCIs under weak grids but result in a decrease in dynamic performance and remain unstable under very weak grids. While the small-signal stability of GCIs operating in grid-forming (GFM) mode is just the opposite: stable under weak or even very weak grids, unstable under strong grids. Both GFL and GFM modes are difficult to meet the stability requirements under large fluctuations in SCR. Therefore, this article proposes a hybrid-mode control strategy for GCIs that can adapt to large fluctuations in SCR. This control strategy weights the modulation signals output from GFL mode and GFM mode, and removes the phase-locked loop of GFL mode, improving the small-signal stability of GCIs under a wide range of SCR. The sequence impedance model of the hybrid-mode GCIs is established, and the small-signal stability is analyzed in this article. The experimental results verify the effectiveness of the proposed strategy.

Telomerase is associated with cellular aging, and its presence limits cellular lifespan. Telomerase by preventing telomere shortening can extend the number of cell divisions for cancer cells. In adult pancreatic cells, telomeres gradually shorten, while in precancerous lesions of cancer, telomeres in cells are usually significantly shortened. At this time, telomerase is still in an inactive state, and it is not until before and after the onset of cancer that telomerase is reactivated, causing cancer cells to proliferate. Methylation of the telomerase reverse transcriptase (TERT) promoter and regulation of telomerase by lactate dehydrogenase B (LDHB) is the mechanism of telomerase reactivation in pancreatic cancer. Understanding the role of telomeres and telomerase in pancreatic cancer will help to diagnose and initiate targeted therapy as early as possible. This article reviews the role of telomeres and telomerase as biomarkers in the development of pancreatic cancer and the progress of research on telomeres and telomerase as targets for therapeutic intervention.

Given the harsh operating circumstances, hypersonic vehicles operating at high Mach number demand accurate advanced information of the flight and health state. Flight parameter prediction is a crucial foundation for achieving this requirement. This work addressed the trade-off between prediction accuracy and efficiency by proposing a flight parameter prediction model with the model pre-training and online parameter updating. To create training data, a mechanism model is established. Then, we construct and evaluate three distinct prediction models to increase prediction accuracy. Finally, we conducted comparative validation experiments to compare the prediction performance of the three models. The findings demonstrate that the suggested model greatly raises prediction accuracy without raising model complexity, better balancing prediction accuracy and efficiency. The prediction accuracy of the suggested model has increased by 81.9% when compared to the traditional model.

• The state-of-the-art LSP technology on Ti alloys is reviewed. • Microstructural evolution characteristics during LSP process are presented. • Improved engineering performance and their mechanism are discussed. • Current challenges and future research directions are proposed. Titanium (Ti) and its alloys are frequently utilized as critical components in a variety of engineering applications because of their high specific strength and excellent corrosion resistance. Compared to conventional surface strengthening technologies, laser shock peening (LSP) has increasingly attracted attention from researchers and industries, since it significantly improves the surface strength, biocompatibility, fatigue resistance, and anti-corrosion ability of Ti and its alloys. Despite numerous studies that have been carried out to elucidate the effects of LSP on microstructural evolution and mechanical properties of Ti and its alloys in recent years, a comprehensive review of recent advancements in the field of Ti and its alloys subjected to LSP is still lacking. In this review, the standard LSP and the novel process designs of LSP assisted by thermal, cryogenic, electropulsing and magnetic fields are discussed and compared. Microstructural evolution, with focuses on the dislocation dynamics, deformation twinning, grain refinement and surface amorphization, during LSP processing of Ti alloys is reviewed. Furthermore, the enhanced engineering performance of the LSP-processed (LSPed) Ti alloys, including surface hardness, wear resistance, fatigue life and corrosion resistance are summarized. Finally, this review concludes by presenting an overview of the current challenges encountered in this field and offering insights into anticipated future trends. [Display omitted] [ABSTRACT FROM AUTHOR]

Grid-forming (GFM) technique is attractive for doubly fed induction generator (DFIG)-based wind turbines (WTs) to realize its stable operation and grid-support ability under weak ac grid. Meanwhile, GFM-DFIG suffers from instability under grid voltage sag due to its poor ability to resist disturbed grid voltage. In this article, focusing on its transient stability under symmetrical grid voltage fault, the large-signal model of GFM-DFIG with voltage-orientation control (VOC) considered is established, based on which its transient behavior is studied. It is found that two types of transient instability exist during a symmetrical grid voltage fault. The first is induced by the inexistence of the postfault equilibrium point (EP). The second is induced by the excessive dynamic deviation between synchronous angle and point of common coupling (PCC) voltage angle. Given that the postfault EP and transient damping are vital for transient stability, an enhanced hybrid-synchronization control (EHSC) strategy based on adaptive Integrator is proposed, through which both the postfault EP and the transient damping can be improved. Finally, theoretical findings and effectiveness of proposed strategy are verified with a 5 kW DFIG-based experimental platform.

A three-phase buck power factor correction (PFC) converter with high frequency and high power density faces the problems of high common-mode (CM) voltage and high voltage stress on switching devices. In this letter, the influence of different pulsewidth modulation (PWM) patterns on CM voltage and voltage stress is studied, and the high-frequency current paths in the three-phase buck PFC converter considering parasitic parameters is revealed. A hybrid PWM pattern is proposed to reduce the CM voltage and voltage stress on switching devices. An experimental prototype 200-kHz switching frequency is built to verify the analysis results in this letter.

Long noncoding RNA (lncRNA) dysregulation has been reported to play a pivotal role in the development of cancers. In this study, we aimed to screen the key lncRNA in oral squamous cell carcinoma (OSCC) via bioinformatics analysis and further validate the function of lncRNA in vitro and in vivo.

As the demand for lactoferrin increases, the search for cost-effective alternative proteins becomes increasingly important. Attention naturally turns to other members of the transferrin family such as ovotransferrin. The iron-binding abilities of these proteins influence their characteristics, although the underlying mechanisms remain unclear. This overview systematically summarizes the effects of the iron-binding ability on the fate of food-derived transferrins (lactoferrin and ovotransferrin) and their potential applications. The findings indicate that iron-binding ability significantly influences the structure of food-derived transferrins, particularly their tertiary structure. Changes in structure influence their physicochemical properties, which, in turn, lead to different behaviors in response to environmental variations. Thus, these proteins exhibit distinct digestive characteristics by the time they reach the small intestine, ultimately performing varied physiological functions in vivo. Consequently, food-derived transferrins with different iron-binding states may find diverse applications. Understanding this capability is essential for developing food-derived transferrins and driving innovation in lactoferrin-related industries.

Totem pole power factor correction rectifiers (TPPFCs) have gained popularity with the advantage of a minimal number of devices for optimal performance, but cause a high output voltage due to the inherent step-up characteristic, limiting the single-stage applications. As the switched capacitor converters (SCCs) feature low voltage stress and high-power density, a hybrid soft-switching step-down power factor correction (PFC) rectifier is proposed in this article, which integrates TPPFC with ladder SCC by redundant switch multiplexing. Similar to the traditional TPPFC, the proposed converter can achieve a unity power factor (PF) and comply with IEC61000-3-2 Class C in universal-input applications. With critical conduction mode (CRM) control, some active switches are turned on and off under soft-switching conditions. Therefore, high-efficiency performance is realized. In addition, an adaptive synchronous timing multiplexing control strategy is presented, achieving low voltage gain and natural capacitor voltage balance characteristics. Finally, a 300-W step-down prototype with 97% peak efficiency and PF of 0.99 is built to verify the theoretical analysis results.

The interaction between multiple virtual synchronous generators (VSGs) has a nonnegligible impact on the transient stability of the multiparalleled VSG grid-connected (MPVGC) system and may even cause a large number of VSGs to undergo transient instability successively. The existing research on the transient stability of VSG focuses on the single VSG grid-connected system, and it is difficult to extend to the transient stability analysis of the MPVGC system. In response to this problem, this article establishes the transient mathematical model of the MPVGC system and compares it with the single VSG grid-connected system. It is found that the interaction between multiple VSGs simultaneously affects the equilibrium point state and transient synchronization process of the MPVGC system. Then, the equilibrium point state of the MPVGC system is quantitatively assessed based on the Newton–Raphson method, and the influence mechanism of the interaction between multiple VSGs on the transient stability of the MPVGC system is revealed. In terms of improving the transient stability of the MPVGC system, an active power distribution method that minimizes the risk of transient instability is proposed to optimize the power angle distribution characteristics of each VSG. Finally, simulations and experimental results verify the correctness of the theoretical analysis and the effectiveness of the proposed method under different working conditions.

The traditional Active Distribution Network (ADN) equivalence method focuses on the characteristics of individual units while disregarding the distinctions from one unit to another. The low accuracy of the typical equivalent model for ADN under large disturbances affects the results of grid stability analysis. This paper proposes a novel dynamic equivalence method for ADNs based on Active Synthesis Load Units (ASLUs), providing a crucial tool for effectively analyzing the response characteristics of ADNs with a high penetration of Inverter-based Distributed Generations (IBDGs). Comprising loads and IBDGs, ASLUs serve as the fundamental units facilitating bidirectional power flow in ADNs. The transient characteristics of ASLUs and the impact of inter-unit differences on the dynamic characteristics of ADNs are analyzed. After studying the indexes that describe the dynamic characteristics of ASLUs, a Dynamic AGglomerative NESting (DAGNES) clustering algorithm is proposed based on the analysis results. Then, the algorithm is applied to group ASLUs based on their dynamic characteristics. Finally, the dynamic equivalent model of the ADN is derived by aggregating parameters from the same group of ASLUs and applying them into the proposed ADN model structure. The simulation results demonstrate that the proposed model accurately reflects the transient characteristics of the ADN under large disturbances.

Synchronous pulsewidth modulation (PWM) scheme is more attractive than asynchronous one in low switching to fundamental frequency ratios, for its better harmonic spectrum. But, when a customized synchronous PWM scheme is incorporated into the field-oriented control, the dynamic response speed usually needs to be limited strictly, otherwise some violent current oscillations would appear. As a negative result, the tracking speed to the command is degraded too low to be used in most applications. To address this problem, existing methods mainly introduced a phase regulation loop inside the current control loop, trying to eliminate the phase error between the sampling phases of desired and actual voltages (i.e., maintaining synchronization), which does bring benefits to the current dynamic response. However, this phase regulation loop is always designed empirically due to the lack of a mathematical model and its interaction with the current loop has not been revealed up to date. As a result, the final performance is still not satisfactory. However, the dynamic response is crucial, especially in new energy vehicle applications. To explore this problem, the phase regulation loop is mathematically modeled first in the discrete-time domain, based on which the whole system including both the current loop and the phase loop is analyzed. Consequently, the reason is discovered and the relationship between the phase loop and the current loop is clarified. Furthermore, a novel phase-error regulator is proposed allowing the phase loop to work in the deadbeat mode and the current loop. Compared with the traditional one, with the proposed phase loop the whole closed-loop system achieves a faster dynamic response and produces much smaller current oscillations. All of the design and analysis are experimentally verified on an 18-kW interior permanent magnet synchronous machines drive test rig.

The Internet of Vehicles (IoV) technology has recently emerged as a popular area of research, and vehicle-to-cloud communication forms the basis of the IoV. This process involves uploading a large amount of information related to the vehicle and its location. The security of vehicle-to-cloud communication thus has a significant impact on the safety of the IoV. This paper proposes a vehicle-to-cloud communication system based on lightweight authentication and extended Quantum Key Distribution. The system supports the wireless distribution of session keys between vehicles and the Quantum Cloud Server (QCS) by using a WAN (Wide Area Network), and supports the wired transmission of quantum keys between the QCS and the Telematics Service Provider (TSP) through a LAN (Local Area Network) by using the BB84 protocol. The system can implement encrypted communication based on quantum physical security in a hybrid network. Moreover, we propose a lightweight identity authentication scheme. An analysis of its performance shows that the proposed system requires a small amount of computation and incurs a low communication overhead. This scheme is applicable to most Internet devices with low computing and communication capacity, and can potentially be used in the IoV framework. We conducted simulations of the proposed system and experiments to test its performance. The maximum average delay in communication in experiments was 40.681 ms and the maximum rate of packet loss was 0.1222%. The proposed system can thus ensure safe and efficient IoV communication.

Graphical abstract:

The behavior of the molten pool during the laser cladding process significantly influences the formability, microstructure, and mechanical properties of the formed part. Particularly in laser cladding procedures involving inclined substrates, alterations in the gravitational orientation adversely affect the shape and flow dynamics of the molten pool, resulting in a marked reduction in forming precision and overall quality. Consequently, a thorough investigation into the flow dynamics of the molten pool on inclined substrates becomes of paramount importance. We conduct an analysis of the forces acting on the molten pool situated on an inclined substrate. Notably, shifts in gravitational forces induce the molten pool to be deflected in the direction of gravity as well as the humping phenomenon. Appropriately balanced Marangoni forces facilitate efficient heat and mass transfer within the molten pool, while excessive Marangoni forces can trigger destabilization. Viscous and frictional forces serve the purpose of mitigating the adverse impact of gravity by impeding the motion of the molten pool fluid. Gas pressure serves a dual role, restraining the upward growth of the molten pool and upholding its stability throughout the laser cladding process. Notably, the center evaporation effect within the molten pool warrants careful consideration for the reduction of porosity and sputtering. Ultimately, we delve into strategies for controlling the fluid behavior of the molten pool. These strategies encompass unit energy input optimization, nozzle angle adjustments, material composition optimization, and the application of auxiliary external fields. The diverse range of control approaches is synthesized, culminating in an outlook on the potential avenues for steering molten pool flow behavior.

Ultrasonic impact peening (UIP) is a highly effective surface engineering technique to improve material durability through peening-induced surface plastic deformation. These improvements are determined by not only the generation of surface compressive residual stresses but also the alteration of surface morphological features. In literature, researchers have focused primarily on the average roughness (Sa) to understand the morphology changes induced by UIP. From the surface engineering perspective, in addition to Sa, other surface morphological characteristics play key roles in determining material durability, particularly surface skewness (Ssk) and surface kurtosis (Sku), which describe the asymmetrical distribution of surface profiles and the sharpness of peak features, respectively. In this study, surface morphological characteristics of API 5L X65 pipeline steel processed by UIP are investigated with a focus on the effects of processing parameters on Sa, Ssk, and Sku. The results indicate that the optimized UIP conditions lead to the preparation of surfaces with valley structures as the dominant feature accompanied by blunt peaks, resulting in the elimination of stress concentration sites towards enhanced material durability. In addition, surface hardness, residual stresses, and peening-induced deformation depth are measured. Furthermore, to gain a comprehensive understanding of the material response and the underlying mechanisms driving surface morphological alterations by UIP, a finite element method (FEM)-based model is developed. By investigating the effect of process parameters (peening amplitude, peening cycles, and pin size) on the surface deformation depth and stress/strain distribution, a correlation between these process variables with surface characteristics is established.

The detection of bisphenol A (BPA) in wastewater is imperative due to its significant environmental impact. In this research, we devised an electrochemical sensor utilizing photoinduced calcium deposition on molecularly imprinted TiO2(MI–Ca–TiO2) for the sensitive and selective detection of BPA. This novel approach combines Ca-doping and molecular imprinting in TiO2, achieving enhanced conductivity and selective binding sites for BPA. The MI–Ca–TiO2sensor demonstrated linear detection ranges from 0.01 to 20 μM and a low detection limit of 6.0 nM. Consistent repeatability was observed across various batches of MI–Ca–TiO2, indicated by a relative standard deviation of 0.8%. Notably, the sensor maintained a high differential pulse voltammetry response even after prolonged storage in a refrigerator. Moreover, in the presence of a 100-fold higher concentration of analogous or interfering ions, the MI–Ca–TiO2nanosheets exhibited a marked current response, affirming their efficacy in BPA detection. These findings indicate the potential of the MI–Ca–TiO2sensor as a simple, cost-effective, and efficient tool for detecting BPA in water.

Phase heterogeneity of bromine–iodine (Br–I) mixed wide-bandgap (WBG) perovskites has detrimental effects on solar cell performance and stability. Here, we report a heterointerface anchoring strategy to homogenize the Br–I distribution and mitigate the segregation of Br-rich WBG-perovskite phases. We find that methoxy-substituted phenyl ethylammonium (x-MeOPEA+) ligands not only contribute to the crystal growth with vertical orientation but also promote halide homogenization and defect passivation near the buried perovskite/hole transport layer (HTL) interface as well as reduce trap-mediated recombination. Based on improvements in WBG-perovskite homogeneity and heterointerface contacts, NiOx-based opaque WBG-perovskite solar cells (WBG-PSCs) achieved impressive open-circuit voltage (Voc) and fill factor (FF) values of 1.22 V and 83%, respectively. Moreover, semitransparent WBG-PSCs exhibit a PCE of 18.5% (15.4% for the IZO front side) and a high FF of 80.7% (79.4% for the IZO front side) for a designated illumination area (da) of 0.12 cm2. Such a strategy further enables 24.3%-efficient two-terminal perovskite/silicon (double-polished) tandem solar cells (da of 1.159 cm2) with a high Vocof over 1.90 V. The tandem devices also show high operational stability over 1000 h during T90lifetime measurements.