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Hydrogen is one of the most promising green energy alternatives due to its high gravimetric energy density, zero-carbon emissions, and other advantages. In this work, a CoFeBP micro-flower (MF) electrocatalyst is fabricated as an advanced water-splitting electrocatalyst by a hydrothermal approach for hydrogen production with the highly efficient hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The fabrication process of the CoFeBP MF electrocatalyst is systematically optimized by thorough investigations on various hydrothermal synthesis and post-annealing parameters. The best optimized CoFeBP MF electrode demonstrates HER/OER overpotentials of 20 mV and 219 mV at 20 mA/cm2. The CoFeBP MFs also exhibit a low 2-electrode (2-E) cell voltage of 1.60 V at 50 mA/cm2, which is comparable to the benchmark electrodes of Pt/C and RuO2. The CoFeBP MFs demonstrate excellent 2-E stability of over 100 h operation under harsh industrial operational conditions at 60 °C in 6 M KOH at a high current density of 1000 mA/cm2. The flower-like morphology can offer a largely increased electrochemical active surface area (ECSA), and systematic post-annealing can lead to improved crystallinity in CoFeBP MFs. [ABSTRACT FROM AUTHOR]

In this work, a novel hybrid SERS platform incorporating hybrid core-shell (HyCoS) AuPd nanoparticles (NPs) and MoS2 nanoplatelets has been successfully demonstrated for strong surface-enhanced Raman spectroscopy (SERS) enhancement of Rhodamine 6G (R6G). A significantly improved SERS signal of R6G is observed on the hybrid SERS platform by adapting both electromagnetic mechanism (EM) and chemical mechanism (CM) in a single platform. The EM enhancement originates from the unique plasmonic HyCoS AuPd NP template fabricated by the modified droplet epitaxy, which exhibits strong plasmon excitation of hotspots at the nanogaps of metallic NPs and abundant generation of electric fields by localized surface plasmon resonance (LSPR). Superior LSPR results from the coupling of distinctive AuPd core-shell NP and high-density background Au NPs. The CM enhancement is associated with the charge transfer from the MoS2 nanoplatelets to the R6G. The direct contact via mixing approach with optimal mixing ratio can effectively facilitate the charges transfer to the HOMO and LUMO of R6G, leading to the orders of Raman signal amplification. The enhancement factor (EF) for the proposed hybrid platform reaches ~1010 for R6G on the hybrid SERS platform. [ABSTRACT FROM AUTHOR]

In this study, a type of direct-drive gearshift system integrated into a motor-transmission coupled drive system is introduced. It used two electromagnetic linear actuators (ELAs) to perform gearshift events. The adoption of ELAs simplifies the architecture of the gearshift system and has the potential to further optimize gearshift performance. However, a number of nonlinearities in the gearshift system should be investigated in order to enhance the performance of the direct-drive gearshift system. An active disturbance rejection control (ADRC) method was selected as the principal shifting control method due to the simple methodology and strong reliability. The nonlinear characteristics of the electromagnetic force produced by the ELA were subsequently reduced using the inverse system method (ISM) technique. The ADRC approach also incorporated an acceleration feedforward module to enhance the precision of displacement control. The extended state observer (ESO) module used a nonlinear function in place of the original function to improve the ability to reject disturbances. Comparative simulations and experiments were carried out between the ADRC method and improved ADRC (IADRC) method. The outcomes demonstrate the effectiveness of the designed control method. The shift force fluctuates less, and the shift jerk decreases noticeably during the synchronization procedure. In conclusion, combined with the optimized IADRC method, the direct-drive gearshift system equipped with ELAs shows remarkable gearshift performance, and it has the potential to be widely used in motor−transmission coupled drive systems for EVs. [ABSTRACT FROM AUTHOR]

Ultra-fine hydrogen produced by electrochemical water splitting without carbon emission is a high-density energy carrier, which could gradually substitute the usage of traditional fossil fuels. The development of high-performance electrocatalysts at affordable costs is one of the major research priorities in order to achieve the large-scale implementation of a green hydrogen supply chain. In this work, the development of a vanadium-doped FeBP (V-FeBP) microsphere croissant (MSC) electrocatalyst is demonstrated to exhibit efficient bi-functional water splitting for the first time. The FeBP MSC electrode is synthesized by a hydrothermal approach along with the systematic control of growth parameters such as precursor concentration, reaction duration, reaction temperature and post-annealing, etc. Then, the heteroatom doping of vanadium is performed on the best FeBP MSC by a simple soaking approach. The best optimized V-FeBP MSC demonstrates the low HER and OER overpotentials of 52 and 180 mV at 50 mA/cm2 in 1 M KOH in a three-electrode system. In addition, the two-electrode system, i.e., V-FeBP || V-FeBP, demonstrates a comparable water-splitting performance to the benchmark electrodes of Pt/C || RuO2 in 1 M KOH. Similarly, exceptional performance is also observed in natural sea water. The 3D MSC flower-like structure provides a very high surface area that favors rapid mass/electron-transport pathways, which improves the electrocatalytic activity. Further, the V-FeBP electrode is examined in different pH solutions and in terms of its stability under industrial operational conditions at 60 °C in 6 M KOH, and it shows excellent stability. [ABSTRACT FROM AUTHOR]

The development of highly efficient and stable electrocatalysts at an affordable cost is an essential component for the large‐scale implementation of green hydrogen production. In this work, the fabrication of porous CoMnB electrocatalyst is demonstrated with the incorporation of boron into the Co‐Mn matrix by an electrochemical approach for bifunctional water electrocatalysis for the first time. The optimized CoMnB electrocatalyst demonstrates an excellent bifunctionality with a low 2‐E turnover voltage of 1.59 V at 20 mA cm−2 in 1 m KOH. The CoMnB shows a comparable water‐splitting current at low current range as compared with the standard benchmark electrodes of Pt/C||RuO2 in 1 m KOH. Then, the CoMnB outperforms the benchmarks at above 800 mA cm−2, indicating a better H2 and O2 generation performance at the industrial operational condition of high current range. The CoMnB also exhibits superior electrocatalytic activity in real sea water +1 m KOH. In addition, the porous CoMnB electrocatalyst exhibits an excellent stability with stable current for continuous 72 h operation at high current and excellent repeatability after 1000 cycles. The result ranks the CoMnB as one of the best transition metal‐based water‐splitting electrocatalysts at low cost with an easy fabrication approach. [ABSTRACT FROM AUTHOR]

Multi-metallic alloy NPs composed of various elemental compositions can surmount the interband threshold limit of mono-metallic NPs and thus can offer a promising route to boost up the performance limit of conventional ultraviolet photodetectors (PDs). In this work, a hybrid UV-PD configuration has been demonstrated by combining the multi-metallic plasmonic alloy NPs of AgCu, AuCu, and AgAuCu on a GaN photoactive layer in order to exploit the improved photo carrier injection by the strong hot electrons and LSPR. Among various devices, the tri-metallic AgAuCu NP PD demonstrates the highest performance with a remarkably high photocurrent of 1.47 × 10−2 A at 1 V with fast rise (Tr) and fall (Tf) times of 170 and 700 ms with a very stable current. This leads to the superior figure-of-merit parameters of the PD with a photoresponsivity of 4.3 × 106 mA W−1, detectivity of 3.52 × 1012 Jones and EQE of 1.39 × 106%, which is ∼16 times higher than the bare GaN PD. This ranks the AgAuCu PD as one of the best GaN based UV photodetectors. The photocurrent enhancement and excellent figure-of-merit can be attributed to the significantly increased photo carrier injection by the efficient hot electron generation via the LSPR and improved interfacial barrier characteristics by the tri-metallic elemental synergy. [ABSTRACT FROM AUTHOR]

This study aimed to explore the role of clusterin released by platelet aggregation in restenosis after carotid endarterectomy. 35 patients who underwent carotid endarterectomy due to carotid artery stenosis were enrolled in this study. They were admitted to the Third Affiliated Hospital of Qiqihar Medical University from January 2018 to January 2019. All the patients were divided into two groups: the restenosis group and the nonrestenosis group, according to the follow-up results within 12 months. Peripheral blood was collected on the first day, 6 months, and 12 months after operation. The expression of CLU in serum of plasma and platelet culture medium was detected by an ELISA experiment. The vascular endothelial cells were cultured in vitro with 100 ng/mL of human recombinant CLU added to the medium. Cell proliferation, migration, and invasion were detected by CCK8, scratch, and Transwell invasion tests. The expression level of TLR3 and NF-κb p65 proteins in cells was detected by western blot. TLR3 knockout plasmids in vascular endothelial cell lines were transfected. Cell proliferation and migration were detected by CCK8 and the scratch assay. The CLU content in peripheral blood plasma and supernatant of platelet culture medium was significantly higher in the restenosis group than that of the control group (p = 0.003) 6 months after operation (p = 0.047) and 12 months after operation (p = 0.011). When CLU was added to vascular endothelial cell culture medium, the proliferation and migration were significantly enhanced. The TLR3/NF-κb p65 protein expression level in cells also significantly increased. After the transfection of TLR3 knockout plasmids into vascular endothelial cell lines, CLU cannot promote the proliferation and migration of vascular endothelial cells. Platelet-released clusterin can induce vascular endothelial cell proliferation and migration by activating the TLR3/NF-kb p65 signaling pathway, leading to carotid artery restenosis after carotid endarterectomy. [ABSTRACT FROM AUTHOR]

SERS is a powerful technique that can offer an extraordinary capacity in the enhancement of weak Raman vibration and identification of molecules at a low concentration. In this work, a versatile hybrid SERS platform is demonstrated by the hybridization of 2D MoS2 nanoplatelets and core–shell PtAu hybrid nanoparticles (HNPs) for the enhancement of Raman vibration of methylene blue (MB). The MB is mixed with the MoS2 nanoplatelets and applied on the uniquely developed PtAu core–shell HNPs and significantly improved SERS is achieved as compared to a general SERS. The PtAu core–shell HNPs can offer the core–shelled PtAu NP configuration along with the highly dense background Au NPs, which exhibit much enhanced distribution of localized surface plasmon resonance (LSPR) and hot spots. The MoS2 nanoplatelets are 2D layered transition metal dichalcogenide (TMD) semiconductors, which can offer an ample charge transfer to the MB. The hybrid SERS platform takes the advantages from both the electromagnetic mechanism (EM) and chemical mechanism (CM). The finite‐different time‐domain (FDTD) simulation demonstrates the enhanced local e‐field distributions and increased maximum local e‐field intensity of the core–shell PtAu HNPs and combination of 2D MoS2 nanoplatelets/core–shell PtAu HNPs. [ABSTRACT FROM AUTHOR]

Electromagnetic linear actuators (ELAs) are used to engage gears in an electric automated manual transmission. The structure is simplified due to the elimination of intermediate mechanisms. An ELA can provide 1500 N of electromagnetic force to drive the synchronizer mechanisms. Additionally, the dynamic characteristics of the actuator are remarkable, improving the performance of shifting gears. To achieve balanceable and comprehensive gearshift performance including shift time, friction work, and degrees of jerk, Pontryagin's minimum principle is employed to optimize the friction torque, and current feed-forward active disturbance rejection control is proposed to track the optimized shift force. Moreover, a double closed-loop controller based on active disturbance rejection control is used to achieve fast and stable displacement control. Comparative simulations and experiments are carried out, and the results indicate that the proposed tracking method can implement the optimal shift force well and can integrate the optimal shift indices, including shift time, degrees of jerk, and friction work. Combined with the proposed control method, the superiority and feasibility of the novel direct-drive electromagnetic gearshift system are validated. [ABSTRACT FROM AUTHOR]

The existing electrically automated manual transmission employs DC motors to carry out gearshift events. It is relatively complicated and has potential to be improved both in structure and transmission efficiency. A novel gearshift system that utilizes a 2-DOF electromagnetic actuator to realize the automation of gearshift is proposed. The structure and working principle are introduced, and the coupling system model of the actuator is developed to investigate its characteristics. The results show that the utilization of the electromagnetic actuator in automated manual transmission gearshift system is appropriate. Multi-stage control strategy including PID algorithm and optimal control is introduced to improve the gearshift quality. A look-up table is developed to adjust the peak force of synchronization process according to the working condition. Finally, the conceptual gearshift system and the control strategy are verified on a test bench. The results show that the controller can adjust the peak force of the synchronization process timely and the designed control strategy achieves the compromise of indexes of gearshift quality. The novel gearshift system is technically feasible. [ABSTRACT FROM AUTHOR]

Keywords: surface enhanced Raman spectroscopy (SERS); localized surface plasmon resonance (LSPR); solid-state dewetting; PtAu hybrid nanoparticles; molybdenum disulfate nanoplatelets EN surface enhanced Raman spectroscopy (SERS) localized surface plasmon resonance (LSPR) solid-state dewetting PtAu hybrid nanoparticles molybdenum disulfate nanoplatelets 1 1 1 11/12/21 20211109 NES 211109 B Hybrid SERS Platform b In article number 2101084, Shusen Lin, Sundar Kunwar, Jihoon Lee, and co-workers demonstrate a hybrid surface enhanced Raman spectroscopy (SERS) platform by hybridizing the MoS SB 2 sb nanoplatelets and core-shelled PtAu hybrid nanoparticles (HNPs) for the SERS enhancement of methylene blue. The unique morphology of PtAu core-shell HNPs, namely the core-shelled PtAu NPs along with the high density background Au NPs, can offer strong localized surface plasmon resonance and high density hot spots. Surface enhanced Raman spectroscopy (SERS), localized surface plasmon resonance (LSPR), solid-state dewetting, PtAu hybrid nanoparticles, molybdenum disulfate nanoplatelets. [Extracted from the article]

The article focuses on a study which explores the relationship between matrix metalloproteinase-2 (MMP-2) expression and colorectal cancer (CRC) survival. It also cites the role of prognostic factors for survival in the management of CRC patients and when choosing the treatment on an individual basis. Furthermore, the study suggests that high levels of MMP-2 expression is a poor prognostic factor for survival in patients with CRC.