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Global Geology 2013年第3期16卷 159-163页

作者： XU Xiaohui CHEN Hui'e WANG Gangcheng college of Construction engineering Jilin University

On the basis of geological investigating work and experimental studies on slide zone soil of one landslide in Tibet,the authors analyzed granulometric composition,clay mineral composition and physical and mechanical properties for the soil in the slide *** soil samples are gravel containing fine *** larger than 2 mm occupy the main proportion with the content 51.5%--68.5%.The relative content of clay minerals is *** clay minerals are illite smectite mixed layer and kaolinite,and their relative contents are 6%--13% and 4%-11%,*** main mineral ingredient is quartz and the relative content is over 30%.Therefore,the soil’s hydrophily is *** cohesion and internal friction angle are high,causing preferable physical-mechanical features of slide zone *** the basis of the obtained data,the landslide stability is evaluated by means of limit equilibrium *** safety factors are 3.191 and 1.92 respectively under both natural and normal water level *** study results show that the landslide is *** can provide the appropriate basis and reference for landslide stability evaluation and landslide control in Tibet.

关键词： slide zone soil granulometric composition clay mineral composition physical-mechanical proper-ty landslide stability analysis

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Independent college of Electrical engineering and Automation professional "improved 3 +1" training mode practice and exploration

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Independent College of Electrical Engineering and Automation...

Challenges and Teaching Reform Strategies in Vocational college engineering Training Courses

2013年教育技术与管理科学国际会议

作者： Zhang Zhong Li Weihua Guangzhou college of South China University of Technology

"Improved 3+1" training model is a new model to the four-year application-oriented undergraduate course of colleges and companies, based on analyze the connotation of "improved 3 +1" training mode, the system of the new training mode electrical engineering and Automation professional courses;experiments, training system;cooperation in training of colleges and companies. Safeguards of is analyzed from multiple aspects in the process, and the implementation effect is evaluated from various aspects. It is the practical exploration and reform innovation for the independent college of Electrical engineering and Automation profession.

关键词： Application-oriented Electrical engineering and Automation improved 3 +1 training mode

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Journal of Contemporary Educational Research 2024年第7期8卷 323-330页

作者： Yueyi Li Xuesong Zhen Jinru Ma Xiaojiao Wang School of Automotive engineering Beijing PolytechnicBeijing 100176China

With the rapid development of vocational education,engineering training has become a crucial course for cultivating highly skilled technical professionals,highlighting its ***,vocational college engineering training courses still face numerous challenges during the actual teaching process,which affect the effectiveness of course teaching and the enhancement of students’engineering *** article thoroughly analyzes the main problems existing in current engineering training course teaching,focusing on four aspects:students’cognitive differences,inadequate course development,poor course adaptability,and limited teaching *** on this analysis and previous research findings,targeted strategies are proposed,including enhancing students’course cognition,clarifying course positioning,improving course adaptability,and optimizing the allocation of teaching ***,this article preliminarily verifies the effectiveness of some reform strategies through a small-scale teaching *** study aims to provide theoretical guidance and practical reference for enhancing the teaching quality of vocational college engineering training courses.

关键词： Vocational colleges engineering training Teaching reform Course development Practical teaching

A Study of L2 Motivational Self System of college engineering Students in Yunnan

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校园英语 2017年第38期 66-66页

作者： Xu Feiyan Yunnan college of Foreign Affairs&Foreign Language

From the perspective of D?rnyei’s L2 Motivational Self System(L2 MSS), which is the latest L2 motivation research model, this study conducted an investigation among students majoring in engineering from one of the universities in Yunnan province, analyzed the factors affecting college English learning for engineering majors. At the same time, the thesis would also provide suggestions to students in motivating themselves in English learning.

关键词： L2 motivation L2 Motivational Self System ideal L2 self ought-to L2 self second language learning experience

An Online Exploratory Maximum Likelihood Estimation Approach to Adaptive Kalman Filtering

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IEEE/CAA Journal of Automatica Sinica 2025年第1期12卷 228-254页

作者： Jiajun Cheng Haonan Chen Zhirui Xue Yulong Huang Yonggang Zhang the college of Intelligent Systems Science and engineering Harbin Engineering University the engineering Research Center of Navigation Instruments Ministry of Education the college of Intelligent Systems Science and engineering the college of Future Technology Harbin Engineering University IEEE

Over the past few decades, numerous adaptive Kalman filters(AKFs) have been proposed. However, achieving online estimation with both high estimation accuracy and fast convergence speed is challenging, especially when both the process noise and measurement noise covariance matrices are relatively inaccurate. Maximum likelihood estimation(MLE) possesses the potential to achieve this goal, since its theoretical accuracy is guaranteed by asymptotic optimality and the convergence speed is fast due to weak dependence on accurate state ***, the maximum likelihood cost function is so intricate that the existing MLE methods can only simply ignore all historical measurement information to achieve online estimation,which cannot adequately realize the potential of MLE. In order to design online MLE-based AKFs with high estimation accuracy and fast convergence speed, an online exploratory MLE approach is proposed, based on which a mini-batch coordinate descent noise covariance matrix estimation framework is developed. In this framework, the maximum likelihood cost function is simplified for online estimation with fewer and simpler terms which are selected in a mini-batch and calculated with a backtracking method. This maximum likelihood cost function is sidestepped and solved by exploring possible estimated noise covariance matrices adaptively while the historical measurement information is adequately utilized. Furthermore, four specific algorithms are derived under this framework to meet different practical requirements in terms of convergence speed, estimation accuracy,and calculation load. Abundant simulations and experiments are carried out to verify the validity and superiority of the proposed algorithms as compared with existing state-of-the-art AKFs.

关键词： Adaptive Kalman filtering coordinate descent maximum likelihood estimation mini-batch optimization unknown noise covariance matrix

Characterization of combined blast-and fragments-induced synergetic damage in polyurea coated liquid-filled container

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Defence Technology(防务技术) 2025年第1期43卷 201-224页

作者： Chen Tao Chong Ji Xin Wang Juan Gu Yuting Wang Changxiao Zhao college of Field engineering Army Engineering University of PLANanjing210007China college of Defense engineering Army Engineering University of PLANanjing211101China

Liquid-filled containers(LFC)are widely used to store and transport petroleum,chemical reagents,and other *** an important target of military strikes and terrorist bombings,LFC are vulnerable to blast waves and *** explore the protective effect of polyurea elastomer on LFC,the damage characteristics of polyurea coated liquid-filled container(PLFC)under the combined loading of blast shock wave and fragments were studied *** microstructure of the polyurea layer was observed by scanning electron microscopy,and the fracture and self-healing phenomena were *** simulation approach was used to explain the combined blast-and fragments-induced on the PLFC in ***,the effects of shock wave and fragment alone and in combination on the damage of PLFC were comprehensively *** showed that the polyurea reduces the perforation rate of the fragment to the LFC,and the self-healing phenomenon could also reduce the liquid loss rate inside the *** polyurea reduces the degree of depression in the center of the LFC,resulting in a decrease in the distance between adjacent fragments penetrating the LFC,and an increase in the probability of transfixion and fracture between *** the close-in blast,the detonation shock wave reached the LFC before the *** does not all have an enhanced effect on the protection of *** presence of internal water enhances the anti-blast performance of the container,and the hydrodynamic ram(HRAM)formed by the fragment impacting the water aggravated the plastic deformation of the *** combined action has an enhancement effect on the deformation of the *** depth of the container depression was 27%higher than that of the blast shock wave alone;thus,it cannot be simply summarized as linear superposition.

关键词： Polyurea Prefabricated fragment Liquid-filled container Hydrodynamic ram Cumulative effect

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Highly selective synthesis and near-infrared photothermal response of heterometallic double trefoil knot and D-type [2]catenanes

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Science China Chemistry 2025年第04期68卷 1383-1391页

作者： Ying Zhao Jian-Xin Yang Yin-Hang Chai Yao He Peng Wang Francisco Aznarez Bo Li Li-Long Dang Lu-Fang Ma college of Chemistry and Chemical engineering Luoyang Normal University college of Chemical and Pharmaceutical engineering Nanyang Normal University

The selective construction of sophisticated supramolecular topologies has always attracted the remarkable attention of researchers. Thus, various molecular knots and catenanes have recently been reported and were obtained either accidentally or by following a previously planned synthetic strategy. Herein, we introduce a series of supramolecular topologies including double trefoil knot(1), trefoil knot(2) and [2]catenanes(4, 5), which were prepared via an elaborated self-assembly strategy by using half-sandwich units based on a flexible pyridyl linker L1. The formation of all the structures has been confirmed by single crystal X-ray diffraction analysis and NMR spectroscopy, and ESI-MS. Remarkably, the central potassium ion of 1 coordinates six oxygen atoms belonging to six amide groups from two trefoil segments. The double trefoil knot 1 and [2]catenanes 4, 5 are stabilized by parallel-displaced π···π stacking interactions(of interlayer distance 3.34–3.82 ?) between the pyridyl fraction and phenyl moieties of three ligands L1, and by edge-to-face-type CH···π interactions(2.64–2.83 ?) between Bi Bz Im conjugated planes and phenyl hydrocarbon bond. Interestingly, the addition/removal of potassium ions resulted in topological transformation between the double trefoil knot 1 and the trefoil knot 2. In addition, the addition of DMF-d7 to a methanolic solution of the double trefoil knot 1 induced its structural conversion into the metallamacrocycle 3. NIR photothermal studies of 1, 4, and 5 showed different photothermal responses in solid and solution states. Thus, the photothermal conversion efficiencies of 4, and 5 were within the limit of 16.8%–45.1% based on different power areas, the number and the fashion of π···π stacking interactions can directly affect the photothermal conversion efficiency, and EPR experiments confirmed the recorded results.

关键词： molecular knots catenanes half-sandwich complexes coordination-driven self-assembly photothermal conversion

A novel self-rotating down-the-hole hammer with impact and rotary functions for directional drilling: Design, modeling, and experiments

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Petroleum Science 2025年第01期22卷 413-429页

作者： Jin-E Cao Hong-Yu Cao Hong-Yun Zhang Jin-He Bai Pin-Lu Cao college of Construction engineering Jilin University

Pneumatic down-the-hole hammer, serving as rock-breaking tool, possesses appeal for directional drilling due to its high rate of penetration. However, corresponding experimental studies on existing hammers for directional drilling have rarely been reported, and a model for evaluating their output performance is absent. This study proposes a novel structure of self-rotating pneumatic hammer(NSH)with a built-in rotational mechanism, which converts partial impact energy of the piston to rotate the drill bit and, consequently, enables dual functions of impact and rotate drill bit. The energy is converted via a screw key-groove mechanism, and the wedge-shaped teeth mechanism ensures that the drill bit rotates clockwise during the piston moves downward. The computational fluid dynamics method is applied to simulate the dynamic response of airflow and piston during the operation of Φ***, a test bench is established to record data concerning chamber pressure and piston displacement, as well as recording its operational status and rock fragmentation during drilling into granite. The results showed that the maximum error between simulated and experimental data is 8.2%.The Φ127NSH successfully achieves dual impact and rotary drilling functions, and granite smoothly feeds and forms a continuous shear rock zone. In addition, the effects of torque load, engagement distance in rotation sleeves, and well deviation angle towards the performance of NSH were studied in detail. The designed Φ127NSH operates at an impact velocity of 3.98 m/s, impact frequency of 12.55 Hz, and rotational speed of 29.51 r/min under a mass-flow rate of 0.18 kg/s, torque load of 400 N·m, engagement distance of 40 mm, and well deviation angle of 0°. The torque load adversely affects the NSH output performance. Increasing the engagement distance improves impact performance while reducing rotational performance. The performance variation of the NSH is minimal when drilling directional wells with v

关键词： Self-rotating pneumatic hammer Directional drilling Fluent CFD simulation Experimental verification

One-step synthesis of hierarchically porous fly ash-based NaX zeolite as assisted by CTAB for low-concentration CO_(2) adsorption

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Particuology 2025年第2期97卷 69-79页

作者： Yao Wei Hong Wu Haowen Kong Yingju Miao Ping Wang college of Environmental and Chemical engineering Dalian UniversityChina college of Chemical and Materials engineering Liupanshui Normal UniversityChina

Despite significant attention being drawn to the synthesis of zeolites from fly ash for CO_(2) adsorption,few studies have focused on hierarchical porous NaX zeolites derived from fly *** existing synthesis methods are often complex,and the role of CTAB in zeolite formation remains *** address these research gaps,we employed a one-step method for synthesizing hierarchically porous fly ash-based NaX zeolites with tunable *** CTAB as a template agent,we conducted a comprehensive investigation into the effects of varying CTAB dosages and aluminum source types on zeolite *** synthesized materials were fully characterized through XRD,FTIR,SEM,TEM,and N2 adsorption/desorption *** results showed that the mesoporous volume of the zeolites can be effectively controlled by adjusting the CTAB/Al_(2)O_(3) *** an optimal ratio of 0.04,the synthesized zeolite has a surface area of 422 m^(2)/g and a mesoporous volume of 0.116 cm^(3)/g,which represents a two-fold increase compared to the NaX synthesized without *** improvement of mesoporosity significantly reduces the resistance to CO_(2) diffusion,thereby enhancing the adsorption performance with a maximum adsorption capacity of 3.37 mmol/g and a high cyclic stability.A further investigation reveals the crucial role of CTAB in promoting mesopore formation and inhibiting crystal growth during zeolite *** findings provide valuable insights into the one-step synthesis of hierarchical porous zeolites.

关键词： One-step method Fly ash Hierarchical porous structure NaX zeolite CTAB

Interfacial Ru nanoclusters in tandem with single atoms on oxygen-vacancy regulated CeO2 for anion exchange membrane seawater-splitting

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Journal of Energy Chemistry 2025年第03期102卷 618-627页

作者： Yue Wang Jing Li Pengfei Yang Hongdong Li Guangrui Xu Yunmei Du Caixia Li Wei Jin Tianyi Ma Zexing Wu Lei Wang Key Laboratory of Eco-chemical engineering Ministry of Education International Science and Technology Cooperation Base of Eco-chemical Engineering and Green Manufacturing College of Chemistry and Molecular Engineering College of Chemical Engineering Qingdao University of Science & Technology college of Chemical engineering Qingdao University of Science and Technology college of Materials Science and engineering Qingdao University of Science & Technology college of Environment and Safety engineering Qingdao University of Science and Technology School of Environmental Science and engineering Suzhou University of Science and Technology School of Science STEM College RMIT University 3083

A hydrogen spillover-bridged water dissociation/hydrogen formation could concurrently promote Volmer/Tafel process and improve the efficiency of hydrogen evolution reaction（HER） under alkaline ***,it is still challenging to promote occurrence of hydrogen spillover for the large interfacial transport barriers of H2O and hydrogen on active ***,the strategy of energy barrier gradient to induce hydrogen spillover was proposed by constructing Ru nanoclusters coupled with single atom onto oxygen vacancy cerium dioxide（Ru/CeO2-Ov-2）.Density functional theory（DFT） calculations uncover that the adsorption/desorption of H2O occurs at the Ru clusters sites and then the dissociated H*spontaneously overflows from Ru clusters with high binding energy into the adjacent Ru single atom sites with low binding energy,which facilitate the hydrogen ***,the synthesized Ru/CeO2-Ov-2 exhibits a small overpotential of 41 mV at 10 mA cm-2and good stability at 500 mA cm-2for 100 h in alkaline seawater,which could be ascribed to the rapid hydrogen spillover and strong coupling interaction between Ru and *** work provides a novel insight that synthesizing cooperative sites with energy barrier gradient helps to promote hydrogen spillover and accelerate the Volmer/Tafel process of HER.

关键词： CeO2 Electrocatalyst Hydrogen evolution reaction Oxygen vacancy Ru