The hydrogen evolution reaction (HER) is of critical importance for sustainable hydrogen production from water electrolysis. In this work, we report a highly efficient and stable noble metal free HER ...catalyst, which is composed of homogeneously distributed metallic Ni and NiMo4N5 nanocrystals. The biphasic nanocrystalline Ni–Mo–N catalyst shows very low overpotential (53mV in 0.5M H2SO4 and 43mV in 1M KOH, at current density 20mA/cm2) and good stability for HER in both acidic and alkaline electrolytes, which is a promising low cost alternative for platinum based HER catalysts.
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•Excellent catalytic performance for the hydrogen evolution reaction. The biphasic nanocrystalline Ni–Mo–N catalyst shows low overpotential very close to that of commercial Pt/C catalyst and very excellent stability in both acidic and alkaline electrolytes.•Combined merits for catalysis due to unique biphasic structure. The Ni–Mo–N catalyst is composed of homogeneously distributed nanocrystals of metallic Ni and Ni–Mo nitride, which combines the merits of high catalytic activity and good acid stability.
The single-mode Dicke model is well known to undergo a quantum phase transition from the so-called normal phase to the superradiant phase (hereinafter called the 'superradiant quantum phase ...transition'). Normally, quantum phase transitions can be identified by the critical behavior of quantities such as entanglement, quantum fluctuations, and fidelity. In this paper, we study the role of the quantum Fisher information (QFI) of both the field mode and the atoms in the ground state of the Dicke Hamiltonian. For a finite but large number of atoms, our numerical results show that near the critical atom-field coupling, the QFI of the atomic and the field subsystems can surpass their classical limits, due to the appearance of nonclassical quadrature squeezing. As the coupling increases far beyond the critical point, each subsystem becomes a highly mixed state, which degrades the QFI and hence the ultimate phase sensitivity. In the thermodynamic limit, we present the analytical results of the QFI and their relationship with the reduced variances of the field mode and the atoms. For each subsystem, we find that there is a singularity in the derivative of the QFI at the critical point, a clear signature of the quantum criticality in the Dicke model.
In this study, we introduced a targeting polymer poly(ethylene glycol)–folic acid (PEG–FA) on the surface of polydopamine (PDA)-modified mesoporous silica nanoparticles (MSNs) to develop the novel ...nanoparticles (NPs) MSNs@PDA–PEG–FA, which were employed as a drug delivery system loaded with doxorubicin (DOX) as a model drug for cervical cancer therapy. The chemical structure and properties of these NPs were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, N2 adsorption/desorption, dynamic light scattering-autosizer, thermogravimetric analysis, and Fourier transform infrared spectroscopy. The pH-sensitive PDA coating served as a gatekeeper. The in vitro drug release experiments showed pH-dependent and sustained drug release profiles that could enhance the therapeutic anticancer effect and minimize potential damage to normal cells due to the acidic microenvironment of the tumor. These MSNs@PDA–PEG–FA achieved significantly high targeting efficiency, which was demonstrated by the in vitro cellular uptake and cellular targeting assay. Compared with that of free DOX and DOX-loaded NPs without the folic targeting ligand, the FA-targeted NPs exhibited higher antitumor efficacy in vivo, implying that they are a highly promising potential carrier for cancer treatments.
Immunotherapy has revolutionized cancer treatment, but its efficacy is severely hindered by the lack of effective predictors. Herein, we developed a homogeneous, low‐volume, efficient, and sensitive ...exosomal programmed death‐ligand 1 (PD‐L1, a type of transmembrane protein) quantitation method for cancer diagnosis and immunotherapy response prediction (HOLMES‐ExoPD‐L1). The method combines a newly evolved aptamer that efficiently binds to PD‐L1 with less hindrance by antigen glycosylation than antibody, and homogeneous thermophoresis with a rapid binding kinetic. As a result, HOLMES‐ExoPD‐L1 is higher in sensitivity, more rapid in reaction time, and easier to operate than existing enzyme‐linked immunosorbent assay (ELISA)‐based methods. As a consequence of an outstanding improvement of sensitivity, the level of circulating exosomal PD‐L1 detected by HOLMES‐ExoPD‐L1 can effectively distinguish cancer patients from healthy volunteers, and for the first time was found to correlate positively with the metastasis of adenocarcinoma. Overall, HOLMES‐ExoPD‐L1 brings a fresh approach to exosomal PD‐L1 quantitation, offering unprecedented potential for early cancer diagnosis and immunotherapy response prediction.
An aptamer‐induced thermophoresis quantitation of exosomal programmed death‐ligand 1 (PD‐L1, a transmembrane protein) was developed, which integrates effective recognition of aptamer and homogeneous thermophoresis. The facile technique is more sensitive and efficient than the current enzyme‐linked immunosorbent assay (ELISA)‐based methods. Translation of the method into standard clinical practice for immunotherapy prediction and monitoring is anticipated.
Because of their curvature, age, track type and maintenance history, metro tracks should be inspected periodically during the planning horizon. Metro companies operate track geometry cars to ...periodically collect measurement data from the tracks by crossing the urban rail transit network. Optimizing the schedule for the track geometry car is a challenge: in addition to minimizing travelling distance, the inspection time interval of the same line should be arranged as equally as possible within the planning horizon. This article proposes a mathematical model for the track geometry car routing problem with periodic demands (TGCRP-PD). To effectively address this problem, a memetic algorithm-based metaheuristic is adopted. The proposed solution approach is applied to a real-world case. The numerical results show that the proposed method could save a dead mileage of 295.016 km (accounting for 48.882%) and greatly improve the level of service intervals.
Copper-catalyzed oxoazidation and alkoxyazidation of indoles has been developed. The dearomatization reaction which leads to versatile 3-azido indolenine and oxindole derivatives in moderate to good ...yields could be used in a further transformation.
Previous corporate social responsibility (CSR) research focused on large businesses rather than small and medium-sized enterprises (SMEs).With the transition of the Chinese economy, more attention ...has been given to the issue of how to motivate manufacturing SMEs to behave in a socially responsible manner. Although research and development (R&D) activities can enhance SMEs innovative abilities through the improvement of their production process and product quality, few studies have explored the direct influence of SMEs’ R&D investment on CSR behavior. This paper explores the relationship between CSR and the R&D investment of Chinese manufacturing SMEs. Based on a balanced panel data of 657 listed manufacturing SMEs from 2015 to 2017, we used random effects regression to find an inverted U-shaped relationship between R&D investment and CSR of SMEs. Furthermore, the relationship is found to be flatter in SMEs that have a good record of regional innovation. The results of this study suggest that suitable investments in R&D and the availability of a fair and supportive environment for regional innovation are indispensable for fulfillment of CSR by SMEs.
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