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In order to improve the wear resistance and high temperature oxidation resistance of TC11 titanium alloy，Nd2O3 particle-doped micro-arc oxidation coatings were prepared by adding different concentrations of Nd2O3 particles.The effect of Nd2O3 concentration on the microstructure and phase composition of micro-arc oxidation coatings on TC11 titanium alloy was studied by scanning electron microscope and X-ray Diffractometer.Meanwhile，the wear resistance and high temperature oxidation resistance of the coating was evaluated.Results showed that after adding Nd2O3 particles，the number of micropores on the surface of the coating decreased，and the coating phase was mainly rutile TiO2 and anatase TiO2.With the increase of Nd2O3 concentration，the content of Nd element in the coating gradually increased，and the coating thickness first increased and then decreased.When the concentration of Nd2O3 was 1 g/L，the comprehensive performance of the prepared micro-arc oxidation coating was the best，which possessed the average thickness of 8.68 μm，the wear loss of 0.43 mg，the wear scar width of 598.04 μm，and the high temperature oxidation weight gain of 0.139 mg/cm2.Compared with the TC11 titanium alloy and the sample without adding Nd2O3 particles，the high temperature oxidation resistance of the micro-arc oxidation coating was significantly improved after adding 1 g/L Nd2O3 particles，and the wear resistance decreased compared with that without adding Nd2O3 particles.

In the era of big data, China’s labor model spirit should not only continue the essence of the past but also show the connotation and practical orientation of the new era. This paper summarizes the dilemmas of teachers’ literacy improvement under the new requirements and proposes a mechanism for improving teachers’ literacy in colleges and universities based on the spirit of model workers. A provincial university was selected as the research subject. Questionnaires were distributed online and offline, and the recovered questionnaires were reviewed and rejected to obtain relevant research data. Pearson’s correlation coefficient and linear regression model were respectively used to empirically analyze the proposed mechanism above. After analysis, the mean value of the implication mechanism, conduction mechanism, feedback mechanism, and safeguard mechanism are all greater than 3, and all of them have a significant correlation with teacher literacy, P

Thin sandstone reservoirs of the fan delta front sub-facies occur in the early Neogene (Miocene) series of the Aketao (Akto) structural belt within the Kunlun piedmont zone of the Tarim Basin. Oil and gas reservoirs in this area correspond to stratigraphic traps. However, owing to the low density of the 2D seismic survey grid deployed in the Aketao belt, inferior seismic data quality, and lack of well logging data, reservoir prediction in this area suffers from a multiplicity of problems and it is difficult to effectively identify sand bodies. Here, a new research approach is proposed involving the use of 3D seismic, well logging, and drilling data from a neighboring highly-explored 3D seismic survey area as a reference for the 2D seismic interpretation of the non-drilled Aketao survey area. Moreover, this approach is integrated with forward modeling and the inversion of post-stack seismic data to identify sand bodies. A comparison of the seismic reflection characteristics clarifies that these 3D and 2D seismic survey areas share similar sedimentary environments. Forward modeling confirms their similar reservoir characteristics, while the reservoir distribution in the 2D seismic survey area is effectively mapped via the inversion. The results show that for a 2D seismic survey area characterized by a low degree of hydrocarbon exploration and appraisal, and a lack of well logging data, the proposed approach can confirm the sedimentary characteristics that correspond to the seismic reflection characteristics, and can quantitatively map the reservoir thickness.

BackgroundLarge size aspherical mirrors have been widely used in space communication systems because of their high angular resolution and energy harvesting ability.PurposeThis study aims to develop a high energy and high flux argon (Ar) ion gun for the rapid polishing of modified silicon layer on the surface of large size SiC aspherical mirror.MethodsFirst of all, Ar ionization was realized by filament and anode grid. Ar+ energy was determined by anode voltage whilst the extractor and electrostatic lenses were employed to achieve Ar+ emission and focusing. The high transmittance of argon ions was realized by adjusting the voltage between the filament and the anode grid to maximize the ionization rate, and adjusting the size and relative position of the electrostatic focusing lens. The materials in the Ar ion gun were selected not only suitable for ultra-high vacuum, but also preventing from vacuum discharge. Then, the parameters of the main components of argon ion gun were determined by theoretical calculation and simulation of the trajectory of argon ion beam. Finally, preliminary experimental tests were carried out to verify its performance.ResultsThe test results show that the Ar+ energy and beam flux can reach 20 keV and 50 μA, respectively, at 30 mm working distance and Ar partial pressure of 1.2×10-2 Pa. The beam size can be continuously adjusted from 19 mm to 24 mm.ConclusionsThis developed argon ion gun with small size, high energy and high flux, can be installed on a vacuum multi-dimensional displacement table for a wide range of movement to achieve high vacuum surface polishing of large aperture optical elements.

The petal blight disease of alpine Rhododendron severely impacts the ornamental and economic values of Rhododendron. Plant secondary metabolites play a crucial role in resisting pathogenic fungi, yet research on metabolites in alpine Rhododendron petals that confer resistance to pathogenic fungi is limited. In the present study, the secondary metabolites in Rhododendron delavayi, R. agastum, and R. irroratum petals with anti-pathogenic activity were screened through disease index analysis, metabolomic detection, the mycelial growth rate, and metabolite spraying experiments. Disease index analysis revealed that R. delavayi petals exhibited the strongest disease resistance, while R. agastum showed the weakest, both under natural and experimental conditions. UHPLC-QTOF-MS/MS analysis identified 355 and 274 putative metabolites in positive and negative ion modes, respectively. The further antifungal analysis of differentially accumulated baicalein, diosmetin, and naringenin showed their half-inhibitory concentrations (IC50) against Neopestalotiopsis clavispora to be 5000 mg/L, 5000 mg/L, and 1000 mg/L, respectively. Spraying exogenous baicalein, diosmetin, and naringenin significantly alleviated petal blight disease caused by N. clavispora infection in alpine Rhododendron petals, with the inhibition rates exceeding 64%. This study suggests that the screened baicalein, diosmetin, and naringenin, particularly naringenin, can be recommended as inhibitory agents for preventing and controlling petal blight disease in alpine Rhododendron. [ABSTRACT FROM AUTHOR]

Exploring efficient and robust self‐supporting hydrogen evolution reaction (HER) electrodes using simple, accessible, and low‐cost synthetic processes is crucial for the commercial application of water electrolysis at high current densities. Ni‐based self‐supporting electrodes are widely studied owing to their low cost and good catalytic performance. However, to date, the preparation of Ni‐based electrodes requires multistep and complex preparation processes. In this study, a novel one‐step in situ sintering method to synthesize mechanically stable and highly active Ni3Se2‐Ni electrodes with well‐controlled morphologies and structures is developed. Their excellent performance and durability can be attributed to the numerous highly active nano‐Ni3Se2 catalysts embedded on the surface of the Ni skeleton, the excellent conductivity of the interconnected conductive network, and the strong interfacial bonding between Ni3Se2 and Ni. As a result, the Ni3Se2‐Ni600 electrode can operate stably at 85 and 400 mA cm−2 for more than 800 and 300 h, respectively. Moreover, the Ni3Se2‐Ni600 electrode displays outstanding stability for over 500 h in a commercial two‐electrode system. This study provides a feasible one‐step synthesis method for low‐cost, high‐efficiency metal selenide‐metal self‐supporting electrodes for water electrolysis. [ABSTRACT FROM AUTHOR]