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Platinum-based catalysts are the best HER catalysts, but their high price affects their mass application, so how to reduce the amount of platinum in catalysts has become a hot research topic. Herein, we synthesized low platinum dosage and highly dispersed nano-alloy catalyst PtNi/CB using a one-step solvothermal approach. Characterization shows that in the PtNi/CB catalyst, nickel element mainly exists in the form of oxidation state and promotes the dissociation of water molecules, resulting in the formation of a hydrogen-rich chemical microenvironment on the catalyst surface, while platinum element mainly exists in the form of metal state, electron flow from nickel to platinum forms an electron-rich platinum structure with high proton affinity, which can well regulate the adsorption/desorption energies of intermediate H*. The combined effect of platinum and nickel enhances catalyst performance and stability. Based on this, the PtNi/CB catalyst requires only 29 mV overpotential to achieve a current density of 10 mA cm−2 in 1 M KOH, which is much better than that of commercial Pt/C catalyst (49 mV), and can be operated stably for a long time. [Display omitted] • One-step solvothermal synthesis of Pt–Ni alloy with only 3.1% Pt loading. • Nickel in the oxidized state promotes the dissociation of water molecules. • Platinum in the metallic state can modulate the adsorption/desorption of H*. • PtNi/CB exhibits HER performance and stability beyond commercial 20% Pt/C. [ABSTRACT FROM AUTHOR]

The development of hydrogen evolution activity (HER) electrocatalyst that can run durably and efficiently under the large current density is of special significance but still challengeable for the massive production of hydrogen. Herein, a CoP/Ni(OH) 2 nanowire catalysts grown on Co foam (CF) with a three-dimensional heterojunction structure has been successfully prepared by electrodepositing nickel hydroxide on the surface of cobalt phosphide. The prepared CoP/Ni(OH) 2 –15 min sample reveals a superior HER activity and stability. It merely requires ultralow overpotentials of 108 and 175 mV to 100 and 500 mA cm−2, respectively. In addition, the long-term stability test shows that the catalyst (CoP/Ni(OH) 2 –15 min) can operate stably for at least 70 h at 400 mA cm−2. Utilizing NiFe-LDH/IF with high OER activity, the NiFe-LDH/IF || CoP/Ni(OH) 2 –15 min catalyst system possesses the same outstanding performance for overall water splitting (OWS), which can accomplish ≈ 500 mA cm−2 at 1.74 V in 1 M KOH electrolyte. Moreover, the NiFe-LDH/IF || CoP/Ni(OH) 2 –15 min couple can work for more than 80 h at 500 mA cm−2, indicating its a great prospect in the area of electrolysis water. Such excellent catalytic performance is mainly attributed to the armor effect of Ni(OH) 2 , which can not only promote the rapid decomposition of water molecules, but also prevent the loss of phosphorus and enhance the synergistic effect of CoP and Ni(OH) 2. This work can offer a significant reference for the design with high-performance and durable transition metal phosphide electrocatalysts. [Display omitted] • CoP/Ni(OH) 2 nanowire is prepared by molten salt method and electrodeposition. • Ni(OH) 2 can improve water dissociation activity and prevent the loss of P from CoP. • CoP/Ni(OH) 2 –15 min requires 108 and 175 mV at 100 and 500 mA cm−2, respectively. • (CoP/Ni(OH) 2 –15 min) operates stably for at least 70 h at 400 mA cm−2 for HER. • CoP/Ni(OH) 2 –15 min possesses more than 80 h at 500 mA cm−2 for water electrolysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • NiCoP-10 g-125℃ nanowires were prepared by molten salt method. • The strong ions interaction in NiCoP can be realized at the optimized condition. • The high metal loading, large specific surface area and fast charge transfer can be obtained. • NiCoP-10 g-125℃ can show ultrahigh activity and stability under high current density. The design and development of cheap and efficient electrocatalysts are particularly imperative for renewable energy, but still a challenge for overall water splitting (OWS). Herein, The NiCoP-10 g-125℃ with three-dimensional (3D) nanowire structures grown on nickel foam (NF) was successfully prepared by a novel molten salt method (MSM), serving as an excellent bifunctional electrocatalyst. The catalyst only needs minimal overpotential of 159 and 391 mV to gain the large current density of 400 mA cm−2 for HER and OER in 1 M KOH, respectively. Meanwhile, the alkaline electrolyzer assembled by two electrodes requires a cell voltage of 1.83 V to achieve 400 mA cm−2 for OWS and runs stably at 100 mA cm−2 for 100 h without apparent potential decay. Such impressive catalytic performance is mainly attributed to the special molten salt synthesis method which provides a liquid environment with strong ions interaction. This special reaction condition contributes to forming 3D nanowire structures with the advantage of high metal loading, large specific surface area, fast charge transfer, and good mechanical strength. Therefore, this work can offer a new avenue for the synthesis of ultrahigh activity bifunctional electrocatalysts. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an efficient method for solving the economic dispatch problem (EDP) through combination of genetic algorithm (GA), the sequential quadratic programming (SQP) technique, uniform design technique, the maximum entropy principle, simplex crossover and non-uniform mutation. The proposed hybrid technique uses GA as the main optimizer, the SQP to fine tune in the solution of the GA run. Based on the maximum entropy principle, the cost function of EDP is approximated by using a smooth and differentiable function to improve the performance of the SQP. An initial population obtained by using uniform design exerts optimal performance of the proposed hybrid algorithm. The effectiveness of the proposed method is validated by carrying out extensive tests on two different EDP with incremental fuel-cost function taking into account the valve-point loadings effects. The result shows that the proposed hybrid genetic algorithm improves the solution accuracy and reliability compared to other techniques for EDP considering valve-point effects. [Copyright &y& Elsevier]

Assessment of operating performance, which is adopted to assess optimal degree for complex industrial process, has been increasing concerned in the last few years. In this study, a supervised probabilistic slow feature analysis (SPSFA) is proposed to assess the optimal degree of process performance by deep mining process variables information on the basis of the probability distribution model. First, the slow features (SFs) are modeled in state–space form as a serial correlation feature to effectively represent the potential variation of performance, and the serial correlation hiding in the performance features reveals the potential changes of performance, which helps improve cognitive depth and assessment accuracy of performance. Then, multi-order dynamic information of SFs is further combined to design the multi-order dynamic index, which accurately and timely depict the dynamic changes of the process. Hence, the proposed method provides an explicit representation of underlying driving forces of performance variations and meaningful physical interpretation of each stage from optimal to non-optimal. In addition, a sparse learning-based non-optimal factor identification method is proposed, which identifies non-optimal factor variables by reconstructing the online estimation of the Kalman filter and using Group Lasso. The feasibility and effectiveness of the proposed method is validated by an actual dense medium coal preparation process and a typical Tennessee Eastman process. • It is the first time to establish the operation performance assessment model based on probability graph model. • Multi-order dynamic information of SFs is further explored to design a multi-order dynamic index to provide an explicit representations of underlying driving forces of performance variations. • A new non-optimal factor recognition method based on sparse learning is proposed to identification of non-optimal factor variables by reconstructing Kalman filter online estimation and using Group Lasso. [ABSTRACT FROM AUTHOR]

Transition metal selenides are promising oxygen evolution reaction (OER) catalysts, and element doping is a strategy to further enhance their catalytic performance. However, the choice of doping elements and methods needs further study. In this work for cobalt selenide, Ni is has been selected for isomorphic doping to NiCoSe 2 with silver doped in bulk to obtain Ag–NiCoSe 2 nanosheet on NF. The addition of nickel can form a eutectic phase with cobalt to obtain an effective synergistic catalytic effect. The addition of Ag can regulate the adsorption energy of the active site and conductivity. The as-prepared Ag–NiCoSe 2 /NF has good catalytic performance for OER, and a current density of 100 mA cm−2 can be achieved with only 270 mV. Its catalytic ability is far superior to that of non-Ag-doped NiCoSe 2 , which is due to the fact that the sheet structure provides more active sites, and the metal doping modulates the electronic configuration, which effectively improves the intrinsic activity. Moreover, Ag–NiCoSe 2 /NF can maintain a long-term high-efficiency catalytic process for more than 20 h at a current density of 100 mA cm−2. Therefore, this work proves that metal doping is of great significance for improving the catalytic activity of transition metal selenides. [Display omitted] • Ag–NiCoSe 2 on NF is prepared by electrodeposition and hydrothermal reaction. • Ag doping can improve the intrinsic activity and conductivity of NiCoSe 2. • Ag–NiCoSe 2 /NF requires 270 mV at 100 mA cm−2 for OER. • Ag–NiCoSe 2 /NF operates stably for at least 20 h at 100 mA cm−2 for OER. • Bulk silver doped Ag–NiCoSe 2 /NF has better properties than surface Ag doped products. [ABSTRACT FROM AUTHOR]

Rationally designing high-activity catalyst for oxygen evolution reaction (OER) is of primary importance due to its sluggish kinetic process in water splitting. Herein, we report a metallic (V) and nonmetallic (F) double doping in Co 3 O 4 with nanoneedles structure, which is synthesized through facile oil bath and annealing. Electrochemical measurements show that the Co 3 O 4 dopped with fluorine and vanadium (F 0.2 -V-Co 3 O 4 -350) only needs a low overpotential of 320 mV to afford a current density of 10 mA cm−2, which is superior to commercial RuO 2. The excellent electrocatalytic performance can be attributed to double doping of vanadium and fluorine which have strong electron absorption effect to optimize the density of electrons in Co 3 O 4. Besides, nanoneedles structure can enlarge exposure of active sites. And its great durability is evaluated through 2000 cycles CV test. Furthermore, the optimal ratio of fluorine to vanadium and different annealing temperatures of the target catalyst are explored reasonably. [Display omitted] • The double doping of V and F has strong effect on the density of electron in Co 3 O 4. • F 0.2 -V-Co 3 O 4 -350 only needs an overpotential of 320 mV at 10 mA cm−2. • The optimal ratio of F to V and annealing temperature have been explored. • The trace introduction of both metallic and nonmetallic can improve OER activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • UE-S-FeBTC is prepared on metal substrate to form Mott-Schottky heterojunction. • S doping strengthens the built-in electric field of FeBTC/NIF. • Ultrasound builds closer contact to enhance BIEF. • UE-S-FeBTC/NIF requires 306 mV at 100 mA cm−2 to catalyze OER. • UE-S-FeBTC/NIF operates stably for at least 12 h at 200 mA cm−2 for OER. Metal–organic frameworks (MOFs) materials are highly efficient materials for catalytic hydrogen production from electrolytic water, but the electronic configuration severely limits catalytic activity. In this study, UE-S-FeBTC was synthesized on metal substrate nickel iron foam (NIF) by one-step electrodeposition to construct Mott Schottky heterojunction. Chemical S doping mixes the p-π conjugation in the overall d-π conjugation system, effectively modulating the electronic configuration of FeBTC and enhancing carrier diffusion at the interface. Moreover, physical ultrasound of the synthesis process results in a tighter contact interface, thus improving the carrier exchange between the semiconductor and the substrate, which causes a further enhancement of flat band potential (FBP). The material exhibits good catalytic activity, requiring only 306 mV overpotential to drive 100 mA cm−2 and remains stable at 200 mA cm−2 for up to 12 h. Excellent catalytic activity derived from closer contact at the Mott Schottky heterojunction interface and the larger specific surface area formed by sonication resulting in the loading of more active sites. The stronger FBP also effectively improves the carrier density at the catalytic active site. This study provides a new design idea for the construction of Mott Schottky heterojunction catalysts with strong FBP. [ABSTRACT FROM AUTHOR]

Osteosarcoma is an aggressive bone tumor characterized by a high level of genetic instability and recurring DNA deletions and amplifications. This study aims to investigate how microRNA-496 (miR-496) affects proliferation, invasion, and migration of human osteosarcoma (OS) cells and in vivo tumorigenicity by targeting eukaryotic translation initiation factor 4E (eIF4E). Microarray-based gene expression profiling involving OS was used in order to identify differentially expressed genes. After that, the interaction between miR-496 expression and OS patients' survival rate was determined. The expression pattern of miR-496 and eIF4E was determined in OS tissues and cells, and their potential relationship was further analyzed by using the dual luciferase reporter gene assay. With the purpose of identifying the functional role miR-496 in OS, cell proliferation, migration, and invasion were measured in cells treated with miR-496 mimic or inhibitor. A nude mouse model was constructed in order to investigate the regulatory effects of miR-496 on tumor growth in vivo by regulating eIF4E. OS cells exhibited a down-regulated expression of miR-496 and an up-regulated expression of eIF4E. miR-496 expression was positively correlated to OS patients' survival rate. Bioinformatics analysis suggested eIF4E would be a direct target of miR-496, and the expression of eIF4E was inhibited by overexpression of miR-496. miR-496 elevation was found to exert suppressive effects on OS cell proliferation, migration and invasion in vitro and tumor growth in vivo , with the effects being reversed using miR-496 depletion. Altogether, the above findings support a conclusion that miR-496 could work as a tumor suppressor in OS through down-regulation of eIF4E. This study may provide a novel target for treatment of OS. • miR-496 is lowly-expressed while eIF4E is highly-expressed in OS cells. • Overexpressed miR-496 inhibits the expression of eIF4E. • miR-496 inhibits the proliferation, invasion and migration of OS cells in vitro. • miR-496 inhibits the OS tumor growth in vivo. • This study laid a therapeutic foundation for further studies on the treatment of OS. [ABSTRACT FROM AUTHOR]

We study theoretically the single-electron triangular zigzag graphene quantum dot in uniform in-plane electric fields. The absorption spectra of the dot are calculated by the tight-binding method. The energy spectra and the distribution of wave functions are also presented to analyse the absorption spectra. The orthogonal zero-energy eigenstates are arranged along to the direction of the external field. The remarkable result is that all intraband transitions and some interband transitions are forbidden when the absorbed light is polarized along the direction of the electric field. With x -direction electric field, all intraband absorption is y polarized due to the electric-field-direction-polarization selection rule. Moreover, with y -direction electric field, all absorption is either x or y polarized due to the parity selection rule as well as to the electric-field-direction-polarization selection rule. Our calculation shows that the formation of the absorption spectra is co-decided by the polarization selection rules and the overlap between the eigenstates of the transition. [ABSTRACT FROM AUTHOR]

[Display omitted] • F is well doped into FeP nanobelt arrays by room temperatures immersion method. • The optimized F-FeP nanobelt arraypossess enhanced HER catalytic activity. • The low overpotentials of 302 mV at 1000 mA cm−2 has been achieved. • The stability test of overall water splitting can last 100 h at 1000 mA cm−2. • DFT and UPS consistently reveal that F doping can lower the d-band center. Modulating the intrinsic activity of transition metal iron-based phosphates though tailoring d-band center has been effective strategy especially for large-scale hydrogen production at high current density. Herein, nonmetallic fluorine atoms are well doped into FeP nanobelt arrays by room temperatures immersion method for enhanced performance of hydrogen evolution reaction (HER) in alkaline solution. Significantly, the optimized fluorine-doped iron phosphide nanobelt array (3F-FeP) possess enhanced HER catalytic activity with low overpotentials of 191, 261 and 302 mV to achieve the 100, 500 and 1000 mA cm−2. Furthermore, the long-time stability test indicates that the NiFe-LDH/IF(+)//3F-FeP/IF(−) couple can last for more than 100 h at high current density of 1000 mA cm−2, which gives it a great potential in the practical electrolytic water industry. Density functional theory (DFT) calculations and ultraviolet photoemission spectroscopy (UPS) characterization consistently reveal that the doping of F can effectively regulate the electronic structure, promote electron transport, lower the d-band center position, optimize the hydrogen adsorption energy, reduce the water splitting energy and the H 2 formation energy of iron phosphate. This work can provide a facile method for the designing strategy of materials with higher catalytic activity for HER. [ABSTRACT FROM AUTHOR]