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1.
Recently, InE has been regarded as a popular education strategy in Chinese universities. However, problems have been exposed in the adoption of InE, for example, in InE courses and competitions. The purpose of this paper is to provide a possible solution to the problems, which is to organize effective InE courses by integrating InE with Inter-Course-level Problem-Based Learning (ICPBL). A detailed case is demonstrated by an ICPBL elective course design with deep integration of InE in the teaching, learning, and assessments. This paper contributes to a new curriculum design for promoting InE education in practically for Chinese universities.  相似文献   
2.
Construction of heterostructured electrocatalyst with interface effect is an effective strategy for enhancing the alkaline hydrogen evolution efficiency, whereas this process often requires complex treatments. Herein, we proposed a one-step electrodeposition method to obtain heterostructured CoNi-LDH@NiCo alloy on Ni foam (NF) through a competition reduction between NO3? group and metal cations in the electrolyte. The HER performance for the CoNi-LDH@NiCo alloy achieved the current density of 10 mA cm?2 at overpotential of 69 mV in 1 M KOH solution, improved 60% for η10 by comparing with the pristine NiCo alloy. Utilizing the specialized adsorption of CoNi-LDH for H2O and the featured attractiveness of NiCo alloy for H atom, the interface effect of the heterostructure electrocatalyst accelerated the dissociation of water molecules and elevated the catalytic kinetics dramatically. This work points out a potential approach towards the easy construction of inexpensive heterostructured electrocatalysts for HER activity in alkaline medium.  相似文献   
3.
针对南关煤矿3205运输巷道工作面掘进与支护困难、巷道变形严重且维修频繁的现状,为破解复杂应力情况下煤柱合理留设宽度这一关键性问题,借助FLAC 3D软件进行了应力场与位移场仿真分析。研究结果表明:显著的水平应力场、邻近的采动应力场与劣化的围岩稳定性三重因素的综合作用是制约3205运输巷正常掘进作业的瓶颈。在不同煤柱宽度方案比选过程中,窄煤柱在应对较强水平应力与剪切应力作用时处于劣势。煤柱宽度越大,采动应力场对煤柱及工作面的影响越小,采掘活动更为安全。经过方案比选,最终确立留设煤柱在复杂应力区段的合理宽度为30 m。  相似文献   
4.
镉(Cd)、硼(B)和一些稀有元素具有较大的热中子吸收截面,在核屏蔽吸收中子领域具有较广泛的应用前景。本文概述了用于核电站乏燃料“湿法”贮存用中子吸收材料的种类,论述了各种中子吸收材料的优点和不足。阐述了铝基碳化硼(B4C/Al)中子吸收材料的研究进展以及不同制备方法的优点和不足,进一步介绍了搅拌摩擦焊方法和扩散焊方法在连接B4C/Al中子吸收材料过程中的优势。在此基础上,对新型中子吸收材料在成分、结构设计方面进行了分析,对未来核屏蔽用中子吸收材料进行了展望。  相似文献   
5.
Chen  Huiling  Zhang  Chunmei  Xu  Qin  Feng  Yuli 《Neural Processing Letters》2022,54(1):181-205
Neural Processing Letters - This paper is concerned with topology identification of stochastic multi-weighted complex networks based on adaptive synchronization. Different from previous work,...  相似文献   
6.
Radioligand therapy targeting the prostate-specific membrane antigen (PSMA) is rapidly evolving as a promising treatment for metastatic castration-resistant prostate cancer. The PSMA-targeting ligand p-SCN-Bn-TCMC-PSMA (NG001) labelled with 212Pb efficiently targets PSMA-positive cells in vitro and in vivo. The aim of this preclinical study was to evaluate the therapeutic potential of 212Pb-NG001 in multicellular tumour spheroid and mouse models of prostate cancer. The cytotoxic effect of 212Pb-NG001 was tested in human prostate C4-2 spheroids. Biodistribution at various time points and therapeutic effects of different activities of the radioligand were investigated in male athymic nude mice bearing C4-2 tumours, while long-term toxicity was studied in immunocompetent BALB/c mice. The radioligand induced a selective cytotoxic effect in spheroids at activity concentrations of 3–10 kBq/mL. In mice, the radioligand accumulated rapidly in tumours and was retained over 24 h, while it rapidly cleared from nontargeted tissues. Treatment with 0.25, 0.30 or 0.40 MBq of 212Pb-NG001 significantly inhibited tumour growth and improved median survival with therapeutic indexes of 1.5, 2.3 and 2.7, respectively. In BALB/c mice, no signs of long-term radiation toxicity were observed at activities of 0.05 and 0.33 MBq. The obtained results warrant clinical studies to evaluate the biodistribution, therapeutic efficacy and toxicity of 212Pb-NG001.  相似文献   
7.
The marine operation of floating liquefied natural gas (FLNG) demands process compactness, flexibility, simplicity of operation, safety, and higher efficiency. The modified single mixed refrigerant (MSMR) process satisfies the FLNG process requirements and is accepted as a suitable technology for FLNG operation. The aim of this study was to develop a plant-wide control structure or strategy that can sustain the economic efficiency of the MSMR process. The NGL recovery and liquefaction units were integrated in the MSMR process to provide a compact plant structure with an efficient operation. Steady-state optimality analysis was intensively conducted in a rigorous dynamic simulation environment to determine the correct variable to sustain the economic efficiency of MSMR process. The results showed that the flow rate ratio of heavy and light mixed refrigerant (HK/LK ratio) is a promising self-optimizing controlled variable. Controlling this variable can sustain the MSMR optimality, even when the process is operated under off-design operating conditions or in the presence of disturbances. Based on the control structure tests, the control configuration with the HK/LK ratio loop showed excellent performance, maintaining the process stability against a range of disturbances. The proposed approach can also be applied to any cryogenic liquefaction technology for determining a possible optimizing controlled variable.  相似文献   
8.
The best control structures for the energy optimizing control of propane precooled mixed refrigerant (C3MR) processes were examined. A first principles‐based rigorous dynamic model was developed to analyze the steady‐state and dynamic behaviors of the C3MR process. The steady‐state optimality of the C3MR process was then examined in a whole operation space for exploring the feasibility of the energy optimizing control for possible control structures. As a result, the temperature difference (TD) between the warm‐end inlet and outlet MR streams was exploited as a promising controlled variable to automatically keep the liquefaction process close to its optimum. The closed‐loop responses were finally evaluated for every possible control structure candidate. Based on the steady‐state optimality and the dynamic performance evaluation, several control structures with a TD loop were proposed to be most favorable for the energy optimizing control of the C3MR process. The proposed optimality approach can be applied to any natural gas liquefaction process for determining a proper controlled variable for optimizing operation. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2428–2441, 2014  相似文献   
9.
为解决飞机CFRP蒙皮涂层高效去除问题,改善重涂涂层附着力,采用塑性磨料射流加工方法对CFRP蒙皮损伤涂层去除,通过分析单颗磨料的速度和冲击力,研究不同冲蚀角度下磨料对涂层的冲蚀行为,探究塑性磨料射流冲蚀角对表面形貌、去除机制、材料去除率、接触角与表面自由能及重涂涂层的附着力方面的影响。结果表明:塑性磨料对涂层的冲蚀机理为塑性变形去除,在30°~70°冲蚀角下,磨料对涂层的冲蚀模式为滑擦、耕犁和切削。随着冲蚀角的增加,颗粒的切向分力减小,法向分力增加,法向冲蚀的冲蚀模式为剪切和挤压变形去除材料去除率递减。在所选冲蚀角范围内,当冲蚀角为30°时,聚氨酯涂层的材料去除率最大。随着冲蚀角的改变,表面粗糙度、润湿性和表面自由能发生变化,当冲蚀角为70°时,重涂后的涂层附着力较好,较初始涂层附着力提高28%左右。研究成果可为飞机CFRP蒙皮涂层的高效去除及附着力的改善提供参考。  相似文献   
10.
本文针对传统设备管理模式存在的问题,阐述了现代设备管理、状态监控和设备故障维修的必要性,并就暖通空调系统的故障特征、故障检测与诊断的方法、实现步骤及相关技术进行了探讨。  相似文献   
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