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Research and Discussion on Flipped Classroom Combined with Case-Based Learning in Pharmacoeconomics Teaching
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作者 Xingwen Zhou Zilong Dang +4 位作者 Xingdong Wang Chen Chen Zhi Rao Ting Wei Yanping Wang 《Journal of Contemporary Educational Research》 2024年第4期120-125,共6页
Objective:To explore the application effect of flipped classroom combined with case-based learning teaching methods in pharmacoeconomics teaching.Methods:The students majoring in clinical pharmacy in 2019 were selecte... Objective:To explore the application effect of flipped classroom combined with case-based learning teaching methods in pharmacoeconomics teaching.Methods:The students majoring in clinical pharmacy in 2019 were selected as the study subjects,and the cost-effectiveness analysis of different dosage forms of Yinzhihuang in the treatment of neonatal jaundice was selected as the teaching case.The flipped classroom combined with case-based learning teaching method was used to carry out theoretical teaching to the students.After the course,questionnaires were distributed through the Sojump platform to evaluate the teaching effect.Results:The results of the questionnaire showed that 85.71%of the students believed that the flipped classroom combined with case-based learning teaching method was helpful in mobilizing the learning enthusiasm and initiative,and improving the comprehensive application ability of the knowledge of pharmacoeconomics.92.86%of the students think that it is conducive to the understanding and memorization of learning content,as well as the cultivation of teamwork,communication,etc.Conclusion:Flipped classroom combined with case-based learning teaching method can improve students’knowledge mastery,thinking skills,and practical application skills,as well as optimize and improve teachers’teaching levels. 展开更多
关键词 Flipped classroom case-based learning teaching method PHARMACOECONOMICS Teaching methods
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Application and development of case-based reasoning in fixture design 被引量:1
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作者 王琪 廖文和 《Journal of Southeast University(English Edition)》 EI CAS 2004年第2期170-175,共6页
Based on the case-based designing (CBD), it is presented that the similarity of the fixtures is described by the fixture information of workpiece and the structure information of feature. Then, the computer-aided fixt... Based on the case-based designing (CBD), it is presented that the similarity of the fixtures is described by the fixture information of workpiece and the structure information of feature. Then, the computer-aided fixture design system is created on case-based reasoning (CBR), in which the attributes information of the main features of workpiece and structure of fixture as case index code are designed for the retrieve of the similar cases, and the structure and hierarchical relation of case library are set up for store. Meanwhile, the algorithm based on the knowledge-guided in the retrieve of the similar cases, the strategy of case adaptation and case storage in which the case identification number is used to distinguish from similar cases are presented. The application of the system in some projects improves the design efficiency and gets a good result. 展开更多
关键词 ALGORITHMS Computer aided design FLOWCHARTING
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水田动力底盘逆向建模与质心验证——基于Geomagic Design X
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作者 何剑飞 曾志浩 +5 位作者 郭梓游 李贵蓉 钟文能 钟顺 王在满 李庆 《农机化研究》 北大核心 2024年第10期248-253,共6页
针对目前农业机械仿真和优化模型精度不高的问题,提出了一种构建精确模型的逆向建模方法。应用光学扫描仪采集点云数据,基于Geomagic Design X处理点云数据并重构零部件模型,在SolidWorks中完成水田动力底盘的装配。以VP6D-CQ型水田动... 针对目前农业机械仿真和优化模型精度不高的问题,提出了一种构建精确模型的逆向建模方法。应用光学扫描仪采集点云数据,基于Geomagic Design X处理点云数据并重构零部件模型,在SolidWorks中完成水田动力底盘的装配。以VP6D-CQ型水田动力底盘为例,将测得的实际质心位置与所建的模型质心位置进行比较,并对提出的逆向建模方法进行了试验验证以及误差分析。结果表明:总质量、x坐标、y坐标、z坐标的误差值分别为4.55%、3.62%、2.23%、4.81%,误差值均在5%内。此方法可构建准确的三维模型,为后续仿真优化数据精确性奠定了基础,与传统的研发相比较,可缩短农业机械研发周期、降低设计成本。 展开更多
关键词 水田 动力底盘 逆向建模 质心验证 Geomagic design X 数字样机
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App Designer辅助教学方法探索与实践——以软件无线电课程为例
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作者 向新 刘宇峰 +2 位作者 梁源 王瑞 何林远 《中国现代教育装备》 2024年第19期148-151,共4页
软件无线电作为通信学科的必修课程,具有承上启下的重要作用。因课程原理抽象、理论公式复杂,学员在学习过程存在理解掌握难、实践应用难等问题。通过对当前软件无线电教学过程中存在的不足与困难进行分析,提出利用MATLAB App Designer... 软件无线电作为通信学科的必修课程,具有承上启下的重要作用。因课程原理抽象、理论公式复杂,学员在学习过程存在理解掌握难、实践应用难等问题。通过对当前软件无线电教学过程中存在的不足与困难进行分析,提出利用MATLAB App Designer辅助课程教学,从教学准备、课堂互动、自主实验、反馈提升四个方面开展课程教学改革。实践表明,该方法对于提升学员的工程思维、系统思维具有显著效果,同时可以增强学员理论联系实际的能力。 展开更多
关键词 软件无线电 MATLAB App designer 教学方法改革 理实结合
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CASE-BASED CONCEPTUAL DESIGN 被引量:3
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作者 LingWeiqing YanJunwei +1 位作者 WangJian XieYoubai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第1期73-77,共5页
The current method of case-based design (CBD) can be well practiced forconfiguration design in which design experience knowledge is involved. However, since the designcase is confined to a certain application domain, ... The current method of case-based design (CBD) can be well practiced forconfiguration design in which design experience knowledge is involved. However, since the designcase is confined to a certain application domain, it is difficult for CBD to be applied toconceptual design process that develops concepts to meet design specifications. Firstly, a functionfactor description space is erected to provide an exhibition room for all functions of design cases.Next, the approach for identifying the space state of function factor in description space isproposed, including the determination of the similarities between function factors of design case.And then a general object-oriented representation for design case is presented by bringing the classof function and in-out flow into the current case representation. Finally, a living example forelectro-pet design that illustrates the implementation of the method for case-based conceptualdesign based on distributed design case repositories is described. 展开更多
关键词 case-based conceptual design Function factor Case representation
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Integration of Theory and Practice in Medical Morphology Curriculum in Postgraduate Training:A Flipped Classroom and Case-based Learning Exercise
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作者 Xi-min HU Zhi-xin LI +5 位作者 Jing DENG Yang HAN Shuang LU Qi ZHANG Zi-qiang LUO Kun XIONG 《Current Medical Science》 SCIE CAS 2023年第4期741-748,共8页
Objective:The integration of training in theory and practice across the medical education spectrum is being encouraged to increase student understanding and skills in the sciences.This study aimed to determine the dec... Objective:The integration of training in theory and practice across the medical education spectrum is being encouraged to increase student understanding and skills in the sciences.This study aimed to determine the deciding factors that drive students'perceived advantages in class to improve precision education and the teaching model.Methods:A mixed strategy of an existing flipped classroom(FC)and a case-based learning(CBL)model was conducted in a medical morphology curriculum for 575 postgraduate students.The subjective learning evaluation of the individuals(learning time,engagement,study interest and concentration,and professional integration)was collected and analyzed after FC-CBL model learning.Results:The results from the general evaluation showed promising results of the medical morphology in the FC-CBL model.Students felt more engaged by instructors in person and benefited in terms of time-saving,flexible arrangements,and professional improvement.Our study contributed to the FC-CBL model in Research Design in postgraduate training in 4 categories:1)advancing a guideline of precision teaching according to individual characteristics;2)revealing whether a learning background is needed for a Research Design course to guide setting up a preliminary course;3)understanding the perceived advantages and their interfaces;and 4)barriers and/or improvement to implement the FC-CBL model in the Research Design class,such as a richer description of e-learning and hands-on practice.Conclusion:Undertaking a FC-CBL combined model could be a useful addition to pedagogy for medical morphology learning in postgraduate training. 展开更多
关键词 flipped classroom case-based learning medical morphology curriculum research design POSTGRADUATE
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Design System of the Two-step Gear Reducer on Case-based Reasoning 被引量:6
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作者 JI Aimin HUANG Quansheng +1 位作者 XU Huanmin CHEN Zhengming 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期671-679,共9页
The design of the two-step gear reducer is a tedious and time-consuming process. For the purpose of improving the efficiency and intelligence of design process, case-based reasoning(CBR) technology was applied to th... The design of the two-step gear reducer is a tedious and time-consuming process. For the purpose of improving the efficiency and intelligence of design process, case-based reasoning(CBR) technology was applied to the design of the two-step gear reducer. Firstly, the current design method for the two-step gear reducer was analyzed and the principle of CBR was described. Secondly, according to the characteristics of the reducer, three key technologies of CBR were studied and the corresponding methods were provided, which are as follows: (a) an object-oriented knowledge representation method, (b) a retrieval method combining the nearest neighbor with the induction indexing, and (c) a case adaptation algorithm combining the revision based on rule with artificial revision. Also, for the purpose of improving the credibility of case retrieval, a new method for determining the weights of characteristics and a similarity formula were presented, which is a combinatorial weighting method with the analytic hierarchy process(AHP) and roughness set theory. Lastly, according to the above analytic results, a design system of the two-step gear reducer on CBR was developed by VC++, UG and Access 2003. A new method for the design of the two-step gear reducer is provided in this study. If the foregoing developed system is applied to design the two-step gear reducer, design efficiency is improved, which enables the designer to release from the tedious design process of the gear reducer so as to put more efforts on innovative design. The study result fully reflects the feasibility and validity of CBR technology in the process of the design of the mechanical parts. 展开更多
关键词 two-step gear reducer case-based reasoning(CBR) weights of characteristics SIMILARITY
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Alloy design for laser powder bed fusion additive manufacturing:a critical review 被引量:3
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作者 Zhuangzhuang Liu Qihang Zhou +4 位作者 Xiaokang Liang Xiebin Wang Guichuan Li Kim Vanmeensel Jianxin Xie 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第2期29-63,共35页
Metal additive manufacturing(AM)has been extensively studied in recent decades.Despite the significant progress achieved in manufacturing complex shapes and structures,challenges such as severe cracking when using exi... Metal additive manufacturing(AM)has been extensively studied in recent decades.Despite the significant progress achieved in manufacturing complex shapes and structures,challenges such as severe cracking when using existing alloys for laser powder bed fusion(L-PBF)AM have persisted.These challenges arise because commercial alloys are primarily designed for conventional casting or forging processes,overlooking the fast cooling rates,steep temperature gradients and multiple thermal cycles of L-PBF.To address this,there is an urgent need to develop novel alloys specifically tailored for L-PBF technologies.This review provides a comprehensive summary of the strategies employed in alloy design for L-PBF.It aims to guide future research on designing novel alloys dedicated to L-PBF instead of adapting existing alloys.The review begins by discussing the features of the L-PBF processes,focusing on rapid solidification and intrinsic heat treatment.Next,the printability of the four main existing alloys(Fe-,Ni-,Al-and Ti-based alloys)is critically assessed,with a comparison of their conventional weldability.It was found that the weldability criteria are not always applicable in estimating printability.Furthermore,the review presents recent advances in alloy development and associated strategies,categorizing them into crack mitigation-oriented,microstructure manipulation-oriented and machine learning-assisted approaches.Lastly,an outlook and suggestions are given to highlight the issues that need to be addressed in future work. 展开更多
关键词 laser powder bed fusion alloy design PRINTABILITY crack mitigation
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Web Layout Design of Large Cavity Structures Based on Topology Optimization 被引量:1
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作者 Xiaoqiao Yang Jialiang Sun Dongping Jin 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2665-2689,共25页
Large cavity structures are widely employed in aerospace engineering, such as thin-walled cylinders, blades andwings. Enhancing performance of aerial vehicles while reducing manufacturing costs and fuel consumptionhas... Large cavity structures are widely employed in aerospace engineering, such as thin-walled cylinders, blades andwings. Enhancing performance of aerial vehicles while reducing manufacturing costs and fuel consumptionhas become a focal point for contemporary researchers. Therefore, this paper aims to investigate the topologyoptimization of large cavity structures as a means to enhance their performance, safety, and efficiency. By usingthe variable density method, lightweight design is achieved without compromising structural strength. Theoptimization model considers both concentrated and distributed loads, and utilizes techniques like sensitivityfiltering and projection to obtain a robust optimized configuration. The mechanical properties are checked bycomparing the stress distribution and displacement of the unoptimized and optimized structures under the sameload. The results confirm that the optimized structures exhibit improved mechanical properties, thus offering keyinsights for engineering lightweight, high-strength large cavity structures. 展开更多
关键词 Topology optimization lightweight design web layout design cavity structure
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Design Principles and Mechanistic Understandings of Non-Noble-Metal Bifunctional Electrocatalysts for Zinc-Air Batteries 被引量:2
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作者 Yunnan Gao Ling Liu +10 位作者 Yi Jiang Dexin Yu Xiaomei Zheng Jiayi Wang Jingwei Liu Dan Luo Yongguang Zhang Zhenjia Shi Xin Wang Ya‑Ping Deng Zhongwei Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期13-48,共36页
Zinc-air batteries(ZABs)are promising energy storage systems because of high theoretical energy density,safety,low cost,and abundance of zinc.However,the slow multi-step reaction of oxygen and heavy reliance on noble-... Zinc-air batteries(ZABs)are promising energy storage systems because of high theoretical energy density,safety,low cost,and abundance of zinc.However,the slow multi-step reaction of oxygen and heavy reliance on noble-metal catalysts hinder the practical applications of ZABs.Therefore,feasible and advanced non-noble-metal elec-trocatalysts for air cathodes need to be identified to promote the oxygen catalytic reaction.In this review,we initially introduced the advancement of ZABs in the past two decades and provided an overview of key developments in this field.Then,we discussed the work-ing mechanism and the design of bifunctional electrocatalysts from the perspective of morphology design,crystal structure tuning,interface strategy,and atomic engineering.We also included theoretical studies,machine learning,and advanced characterization technologies to provide a comprehensive understanding of the structure-performance relationship of electrocatalysts and the reaction pathways of the oxygen redox reactions.Finally,we discussed the challenges and prospects related to designing advanced non-noble-metal bifunctional electrocatalysts for ZABs. 展开更多
关键词 Zinc-air batteries Bifunctional electrocatalysts design principles Mechanistic understandings
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Accelerated design of high-performance Mg-Mn-based magnesium alloys based on novel bayesian optimization 被引量:2
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作者 Xiaoxi Mi Lili Dai +4 位作者 Xuerui Jing Jia She Bjørn Holmedal Aitao Tang Fusheng Pan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期750-766,共17页
Magnesium(Mg),being the lightest structural metal,holds immense potential for widespread applications in various fields.The development of high-performance and cost-effective Mg alloys is crucial to further advancing ... Magnesium(Mg),being the lightest structural metal,holds immense potential for widespread applications in various fields.The development of high-performance and cost-effective Mg alloys is crucial to further advancing their commercial utilization.With the rapid advancement of machine learning(ML)technology in recent years,the“data-driven''approach for alloy design has provided new perspectives and opportunities for enhancing the performance of Mg alloys.This paper introduces a novel regression-based Bayesian optimization active learning model(RBOALM)for the development of high-performance Mg-Mn-based wrought alloys.RBOALM employs active learning to automatically explore optimal alloy compositions and process parameters within predefined ranges,facilitating the discovery of superior alloy combinations.This model further integrates pre-established regression models as surrogate functions in Bayesian optimization,significantly enhancing the precision of the design process.Leveraging RBOALM,several new high-performance alloys have been successfully designed and prepared.Notably,after mechanical property testing of the designed alloys,the Mg-2.1Zn-2.0Mn-0.5Sn-0.1Ca alloy demonstrates exceptional mechanical properties,including an ultimate tensile strength of 406 MPa,a yield strength of 287 MPa,and a 23%fracture elongation.Furthermore,the Mg-2.7Mn-0.5Al-0.1Ca alloy exhibits an ultimate tensile strength of 211 MPa,coupled with a remarkable 41%fracture elongation. 展开更多
关键词 Mg-Mn-based alloys HIGH-PERFORMANCE Alloy design Machine learning Bayesian optimization
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Inverse design of mechanical metamaterial achieving a prescribedconstitutive curve 被引量:1
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作者 Zongliang Du Tanghuai Bian +4 位作者 Xiaoqiang Ren Yibo Jia Shan Tang Tianchen Cui Xu Guo 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第1期16-22,共7页
Besides exhibiting excellent capabilities such as energy absorption,phase-transforming metamaterials offer a vast design space for achieving nonlinear constitutive relations.This is facilitated by switching between di... Besides exhibiting excellent capabilities such as energy absorption,phase-transforming metamaterials offer a vast design space for achieving nonlinear constitutive relations.This is facilitated by switching between different patterns under deformation.However,the related inverse design problem is quite challenging,due to the lack of appropriate mathematical formulation and the convergence issue in the post-buckling analysis of intermediate designs.In this work,periodic unit cells are explicitly described by the moving morphable voids method and effectively analyzed by eliminating the degrees of freedom in void regions.Furthermore,by exploring the Pareto frontiers between error and cost,an inverse design formulation is proposed for unit cells.This formulation aims to achieve a prescribed constitutive curve and is validated through numerical examples and experimental results.The design approach presented here can be extended to the inverse design of other types of mechanical metamaterials with prescribed nonlinear effective properties. 展开更多
关键词 METAMATERIAL Pattern-transformation Constitutive curve Inverse design
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Machine learning for membrane design and discovery 被引量:1
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作者 Haoyu Yin Muzi Xu +4 位作者 Zhiyao Luo Xiaotian Bi Jiali Li Sui Zhang Xiaonan Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第1期54-70,共17页
Membrane technologies are becoming increasingly versatile and helpful today for sustainable development.Machine Learning(ML),an essential branch of artificial intelligence(AI),has substantially impacted the research an... Membrane technologies are becoming increasingly versatile and helpful today for sustainable development.Machine Learning(ML),an essential branch of artificial intelligence(AI),has substantially impacted the research and development norm of new materials for energy and environment.This review provides an overview and perspectives on ML methodologies and their applications in membrane design and dis-covery.A brief overview of membrane technologies isfirst provided with the current bottlenecks and potential solutions.Through an appli-cations-based perspective of AI-aided membrane design and discovery,we further show how ML strategies are applied to the membrane discovery cycle(including membrane material design,membrane application,membrane process design,and knowledge extraction),in various membrane systems,ranging from gas,liquid,and fuel cell separation membranes.Furthermore,the best practices of integrating ML methods and specific application targets in membrane design and discovery are presented with an ideal paradigm proposed.The challenges to be addressed and prospects of AI applications in membrane discovery are also highlighted in the end. 展开更多
关键词 Machine learning Membranes AI for Membrane DATA-DRIVEN design
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Case-based retrieval approach for machining fixture design utilizingontology 被引量:1
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作者 高博 阎艳 +2 位作者 丁洪生 张发平 王国新 《Journal of Beijing Institute of Technology》 EI CAS 2014年第3期352-357,共6页
In order to develop an intelligent case-based reasoning (CBR) system to reuse fixture de- sign knowledge, ontology technology was integrated in CBR system by semantic annotation of fixture design case. Domain ontolo... In order to develop an intelligent case-based reasoning (CBR) system to reuse fixture de- sign knowledge, ontology technology was integrated in CBR system by semantic annotation of fixture design case. Domain ontology of fixture design was constructed; concepts and relations were de- fined and represented. The 2-level similarity evaluation approach of domain ontology was presented. The concept similarity of cases was calculated as the first grade case retrieval. Numerical measure- ment was the second grade case retrieval, which adopted various methods to calculate different types of attribute values. The problem of similarity measurement of fixture design case was resolved. Pro- totype system based on the proposed method was illustrated and the retrieval approach was proved to be efficient. 展开更多
关键词 fixture case ONTOLOGY case-based reasoning similarity measurement
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Deep Insight of Design,Mechanism,and Cancer Theranostic Strategy of Nanozymes 被引量:1
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作者 Lu Yang Shuming Dong +6 位作者 Shili Gai Dan Yang He Ding Lili Feng Guixin Yang Ziaur Rehman Piaoping Yang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期165-217,共53页
Since the discovery of enzyme-like activity of Fe3O4 nanoparticles in 2007,nanozymes are becoming the promising substitutes for natural enzymes due to their advantages of high catalytic activity,low cost,mild reaction... Since the discovery of enzyme-like activity of Fe3O4 nanoparticles in 2007,nanozymes are becoming the promising substitutes for natural enzymes due to their advantages of high catalytic activity,low cost,mild reaction conditions,good stability,and suitable for large-scale production.Recently,with the cross fusion of nanomedicine and nanocatalysis,nanozyme-based theranostic strategies attract great attention,since the enzymatic reactions can be triggered in the tumor microenvironment to achieve good curative effect with substrate specificity and low side effects.Thus,various nanozymes have been developed and used for tumor therapy.In this review,more than 270 research articles are discussed systematically to present progress in the past five years.First,the discovery and development of nanozymes are summarized.Second,classification and catalytic mechanism of nanozymes are discussed.Third,activity prediction and rational design of nanozymes are focused by highlighting the methods of density functional theory,machine learning,biomimetic and chemical design.Then,synergistic theranostic strategy of nanozymes are introduced.Finally,current challenges and future prospects of nanozymes used for tumor theranostic are outlined,including selectivity,biosafety,repeatability and stability,in-depth catalytic mechanism,predicting and evaluating activities. 展开更多
关键词 Nanozymes Classification Prediction and design Catalytic mechanism Tumor theranostics
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Electrolyte Design for Low‑Temperature Li‑Metal Batteries:Challenges and Prospects 被引量:1
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作者 Siyu Sun Kehan Wang +3 位作者 Zhanglian Hong Mingjia Zhi Kai Zhang Jijian Xu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期365-382,共18页
Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements ... Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases.Herein,this review critically outlines electrolytes’limiting factors,including reduced ionic conductivity,large de-solvation energy,sluggish charge transfer,and slow Li-ion transportation across the electrolyte/electrode interphases,which affect the low-temperature performance of Li-metal batteries.Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding.Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared.Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries. 展开更多
关键词 Solid electrolyte interphase Li metal Low temperature Electrolyte design BATTERIES
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Design,test,and verification of in-situ condition preserved coring and analysis system in lunar-based simulation environment 被引量:1
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作者 Haichun Hao Mingzhong Gao +10 位作者 Yan Wu Zheng Gao Yongcheng Li Xuemin Zhou Peng Chu Xuan Wang Jiahua Li Lang Zhou Jie Song Tianxiang Ao Yikun Yang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1259-1272,共14页
The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and soci... The lunar surface and its deep layers contain abundant resources and valuable information resources,the exploration and exploitation of which are important for the sustainable development of the human economy and society.Technological exploration and research in the field of deep space science,especially lunar-based exploration,is a scientific strategy that has been pursued in China and worldwide.Drilling and sampling are key to accurate exploration of the desirable characteristics of deep lunar resources.In this study,an in-situ condition preserved coring(ICP-Coring)and analysis system,which can be used to test drilling tools and develop effective sampling strategies,was designed.The key features of the system include:(1)capability to replicate the extreme temperature fluctuations of the lunar environment(-185 to 200℃)with intelligent temperature control;(2)ability to maintain a vacuum environment at a scale of 10^(-3) Pa,both under unloaded conditions within Ф580 mm×1000 mm test chamber,and under loaded conditions using Ф400 mm×800 mm lunar rock simulant;(3)application of axial pressures up to 4 MPa and confining pressures up to 3.5 MPa;(4)sample rotation at any angle with a maximum sampling length of 800 mm;and(5)multiple modes of rotary-percussive drilling,controlled by penetration speed and weight on bit(WOB).Experimental studies on the drilling characteristics in the lunar rock simulant-loaded state under different drill bit-percussive-vacuum environment configurations were conducted.The results show that the outgassing rate of the lunar soil simulant is greater than that of the lunar rock simulant and that a low-temperature environment contributes to a reduced vacuum of the lunar-based simulated environment.The rotary-percussive drilling method effectively shortens the sampling time.With increasing sampling depth,the temperature rise of the drilling tools tends to rapidly increase,followed by slow growth or steady fluctuations.The temperature rise energy accumulation of the drill bits under vacuum is more significant than that under atmospheric pressure,approximately 1.47 times higher.The real-time monitored drilling pressure,penetration speed and rotary torque during drilling serve as parameters for discriminating the drilling status.The results of this research can provide a scientific basis for returning samples from lunar rock in extreme lunar-based environments. 展开更多
关键词 Lunar-based Large temperature difference Vacuum Drilling and coring System design
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Molecular Mechanism and Molecular Design of Lubricating Oil Antioxidants 被引量:1
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作者 Su Shuo Long Jun +2 位作者 Duan Qinghua Zhou Han Zhao Yi 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期135-145,共11页
To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established here.The molecular me... To overcome the limitations of traditional experimental“trial and error”methods in lubricant additive design,a new molecular design method based on molecular structure parameters is established here.The molecular mechanism of the antioxidant reaction of hindered phenol,diphenylamine,and alkyl sulfide are studied via molecular simulations.Calculation results show that the strong electron-donating ability and high hydrogen-donating activity of the antioxidant molecule and the low hydrogen-abstracting activity of free radicals formed after dehydrogenation are the internal molecular causes of the shielding of phenol and diphenylamine from scavenging peroxy free radicals,and the strong electron-donating ability is the internal molecular cause of the high activity of thioether in decomposing alkyl hydrogen peroxide.Based on this antioxidant molecular mechanism,a molecular design rule of antioxidant is proposed,namely“high EHOMO,large Q(S),low bond dissociation energy BDE(O—H)and BDE(N—H)”.Two new antioxidants,PAS-I and PAS-II,are designed and prepared by chemical bonding of hindered phenol,diphenylamine,and sulfur atoms.Experimental results show that these antioxidants both have excellent antioxidant effects in lubricating oil,and that PAS-II is the superior antioxidant,consistent with theoretical predictions. 展开更多
关键词 lubricating oil ANTIOXIDANT molecular mechanism molecular design antioxidant performance
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Recent advances in cobalt phosphide-based materials for electrocatalytic water splitting:From catalytic mechanism and synthesis method to optimization design 被引量:1
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作者 Rongrong Deng Mengwei Guo +1 位作者 Chaowu Wang Qibo Zhang 《Nano Materials Science》 EI CAS CSCD 2024年第2期139-173,共35页
Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high... Electrochemical water splitting has long been considered an effective energy conversion technology for trans-ferring intermittent renewable electricity into hydrogen fuel,and the exploration of cost-effective and high-performance electrocatalysts is crucial in making electrolyzed water technology commercially viable.Cobalt phosphide(Co-P)has emerged as a catalyst of high potential owing to its high catalytic activity and durability in water splitting.This paper systematically reviews the latest advances in the development of Co-P-based materials for use in water splitting.The essential effects of P in enhancing the catalytic performance of the hydrogen evolution reaction and oxygen evolution reaction are first outlined.Then,versatile synthesis techniques for Co-P electrocatalysts are summarized,followed by advanced strategies to enhance the electrocatalytic performance of Co-P materials,including heteroatom doping,composite construction,integration with well-conductive sub-strates,and structure control from the viewpoint of experiment.Along with these optimization strategies,the understanding of the inherent mechanism of enhanced catalytic performance is also discussed.Finally,some existing challenges in the development of highly active and stable Co-P-based materials are clarified,and pro-spective directions for prompting the wide commercialization of water electrolysis technology are proposed. 展开更多
关键词 Co-P electrocatalysts Water splitting Hydrogen production Catalytic mechanism Synthesis technique Optimization design
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双十字路口交通灯控制Stateflow和App Designer仿真
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作者 张悦 周泽震 +1 位作者 颜秀铭 杨燕 《电气电子教学学报》 2024年第3期218-224,共7页
为培养学生能够独立从事自动化相关领域的工程设计、应用研究,解决自动化领域复杂工程实施过程中遇到的关键技术问题,以双十字路口交通灯为研究对象,为计算机辅助建模与仿真类课程设计了一个综合性教学案例。教学案例主要内容为双十字路... 为培养学生能够独立从事自动化相关领域的工程设计、应用研究,解决自动化领域复杂工程实施过程中遇到的关键技术问题,以双十字路口交通灯为研究对象,为计算机辅助建模与仿真类课程设计了一个综合性教学案例。教学案例主要内容为双十字路口Simulink/Stateflow建模与基于Matlab App Designer的交通灯控制可视化仿真。通过此教学案例的实施,明显提高了学生对Matlab的综合应用和工程设计能力,并为后续课程“单片机原理及应用”和“电气控制和PLC”作铺垫。 展开更多
关键词 双十字路口 交通灯控制 SIMULINK STATEFLOW App designer
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