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A simple one-step hydrothermal method to synthesize interlayer-expanded molybdenum disulfide microflowers (E-MoS2) by increasing the proportion of thiourea in the reactant was proposed. In the method, ammonium thiocyanate, the product of thiourea conversion in hydrothermal reaction, is embedded into the interlayer of MoS2 formed in situ to expand the layer spacing, which avoids the complex synthesis process of traditional E-MoS2 and the introduction of foreign species and templates. The E-MoS2 reveals a small Tafel slope of 68.5 mV/dec and a low overpotential of 285 mV at -10 mA/cm2, markedly lower than those of initial MoS2 counterpart (122.2 mV/dec and 588 mV, respectively), indicating its excellent hydrogen evolution performance. Compared with the original MoS2, the enhanced hydrogen evolution performance of E-MoS2 can be attributed to the following reasons: the expansion of interlayer spacing optimizes the electronic structure of MoS2, thereby improving its conductivity and reducing the hydrogen adsorption free energy; the in situ intercalation of ammonium thiocyanate inhibits the growth and reduces the size of microflowers during the synthesis process, thus exposing more active sites for E-MoS2. Therefore, the E-MoS2 is expected to be a promising non-noble metal electrocatalyst for hydrogen evolution reaction.

An anion-cation co-doping strategy was proposed, and the Mn and P co-doped MoS2 microflowers (Mn, P)-MoS2 catalyst were prepared successfully by one-step hydrothermal reaction for hydrogen evolution reaction(HER). The structure, morphology, chemical composition and valence state were characterized by X-ray diffraction, Raman spectra, scanning electron microscope, X-ray photoelectron spectroscopy and energy dispersive spectroscopy, and the HER performance was performed by electrochemical workstation for (Mn, P)-MoS2. The results show that Mn and P atoms are successfully incorporated into the MoS2 lattice, and the hydrogen evolution overpotential of (Mn, P)-MoS2 at a current density of 10 mA·cm-2 is 235 mV and a small Tafel slope of 61.2 mV·dec-1, which are lower than those of the pure MoS2 and Mn-cation or P-anion doped MoS2. Meanwhile, (Mn, P)-MoS2 presents excellent HER stability. The excellent HER performance of (Mn, P)-MoS2 could be attributed to: the incorporation of Mn and P activates the inert basal plane, optimizes the electronic structure and increases the conductivity of MoS2. The synergistic interaction between Mn and P realizes the complementary advantage of single anion or cation doping, and it increases the number of active sites at basal plane for hydrogen evolution, thus speeding up the Volmer electrochemical desorption step.

In this paper, we designed double V-shaped Al/Ni multilayer energy-containing microdevices with different V-angles, and we performed finite element modeling and simulation of the heat transfer process of the designed energy-containing microdevice. Temperature-dependent resistivity was introduced to effectively simulate the phase change during ignition. We simulated the temperature and current density distribution in the central region of the Al/Ni multilayer energy-containing microdevice and predicted the ignition voltage threshold for the specific device structure. Al/Ni multilayer energy-containing microdevices with different V-angles were prepared by electron beam evaporation technology, and ignition experiments on the prepared devices under the excitation of 47 μF capacitance were conducted. The experimental results show that the critical voltage of ignition increases with the increase in the V-angle, which verifies the correctness of the proposed finite element model. [ABSTRACT FROM AUTHOR]

[Purpose/Significance] The reading promotion at university libraries is advancing to professional reading, and this is consistent with the goal of learning support service. The purpose of this study is to integrate the process, avoid the homogenization of reading promotion, and serve the undergraduate teaching and personnel training with more characteristics. [Method/Process] Taking the reading promotion of architecture discipline as an example, this paper draws lessons from the learning support service model based on information literacy education, and summarizes the integration path of curriculum learning, bibliographic discussion and interdisciplinary learning, so as to bring professional reading into the framework of learning support services. [Results/Conclusions] The integration of reading promotion and learning support service provides a new idea for the innovation of a university library's routine service. Reading promotion makes learning support service more generalized, from interdisciplinary learning, mental health and happiness to aesthetic education. It reflects the ultimate goal of university library service education. Reading promotion will build integrated learning support system and learning support community with new positioning and influence, and promote the role change of university librarians from teaching assistants to participants.

After biochemical treatment of coking wastewater,the organic matter is difficult to reduce further.In order to meet the emission requirements,the effluent shall be subjected to an advanced treatment to reduce its organic matter.This paper treats the coking wastewater by the combined coagulation-Fenton method.The results show that:When the influent COD is 250~400 mg/L,the optimal coagulation conditions are as follows:coagulant PFS dosage:800 mg/L;pH:8;CPAM dosage:0 mg/L;and stirring time:15 min.The optimal conditions of Fenton are as below:Fe2+ dosage:302.38 mg/l;n(Fe2+)∶n(H2O2):1.00∶6.84;initial pH:3.84;reaction time:125.84 min.After the advanced treatment by coagulation-Fenton oxidation,the organic matter concentration decreases from 250~400 mg/L to 60 mg/L or below,and the effluent meets the Emission Standard of Pollutants for Coking Chemical Industry (GB 16171—2012).