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Journal of Materials Science & Technology 2020年第23期58卷 55-62页

作者： Gongcheng Yao chezheng cao Shuaihang Pan Jie Yuan Igor De Rosa Xiaochun Li Department of Materials Science and Engineering University of CaliforniaLos AngelesCA 90095USA Department of Mechanical and Aerospace Engineering University of CaliforniaLos AngelesCA 90095USA

Ultrafine-grained(UFG)/nanocrystalline materials possess novel properties. Refining as-solidified grains of metals to the ultrafine and even nanometer scale by nanoparticles via slow cooling has been recently discovered. Here, we report that microparticles(CrB and CrB_(2)) with surface nanofeatures can also enable ultrafine/nano grains via slow cooling. CrB/CrB_(2) microparticles, formed by coalescence of nanoparticles in Cu matrix, display surface nanofeatures, which induce substantial grain refinement and stabilization down to the ultrafine/nano scale. The UFG Cu/Cr B and Cu/CrB_(2) samples exhibit exceptional thermal stability, comparable to UFG Cu induced by nanoparticles, without coarsening after annealing at 600°C for 1 h. The microhardness, strengths, and Young's moduli of the Cu/Cr B and Cu/CrB_(2) samples are significantly enhanced over pure Cu. This discovery has great potential to advance the mass production UFG/nanocrystalline for widespread applications.

关键词： Copper Microparticles with nanofeatures Casting Ultrafine grains Thermal stability

Quantitative phase imaging based on holography:trends and new perspectives

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Light(Science & Applications) 2024年第7期13卷 1235-1277页

作者： Zhengzhong Huang Liangcai cao Department of Precision Instrument Tsinghua UniversityBeijing 100084China

In 1948,Dennis Gabor proposed the concept of holography,providing a pioneering solution to a quantitative description of the optical *** 75 years of development,holographic imaging has become a powerful tool for optical wavefront measurement and quantitative phase *** emergence of this technology has given fresh energy to physics,biology,and materials *** holography(DH)possesses the quantitative advantages of wide-field,non-contact,precise,and dynamic measurement capability for *** has unique capabilities for the propagation of optical fields by measuring light scattering with phase *** offers quantitative visualization of the refractive index and thickness distribution of weak absorption samples,which plays a vital role in the pathophysiology of various diseases and the characterization of various *** provides a possibility to bridge the gap between the imaging and scattering *** propagation of wavefront is described by the complex *** complex-value in the complex-domain is reconstructed from the intensityvalue measurement by camera in the ***,we regard the process of holographic recording and reconstruction as a transformation between complex-domain and real-domain,and discuss the mathematics and physical principles of *** review the DH in underlying principles,technical approaches,and the breadth of *** conclude with emerging challenges and opportunities based on combining holographic imaging with other methodologies that expand the scope and utility of holographic imaging even *** multidisciplinary nature brings technology and application experts together in label-free cell biology,analytical chemistry,clinical sciences,wavefront sensing,and semiconductor production.

关键词： holographic phase precise

Dynamic Setting Method of Assessment Indicators for Power Curves of Renewable Energy Sources Considering Scarcity of Reserve Resources

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 101-114页

作者： Minghao cao Jilai Yu the Department of Electrical Engineering Harbin Institute of TechnologyHarbinChina

With the increasing proportion of renewable energy sources(RESs)in power grid,the reserve resource(RR)scarcity for correcting power deviation of RESs has become a potential ***,the power curve of RES needs to be more rigorously *** RR scarcity varies during different time periods,so the values of assessment indicators should be dynamically *** assessment indicators in this paper include two aspects,i.e.,deviation exemption ratio and penalty ***,this paper proposes a method for dynamically calculating the supply capacity and RR cost,primarily taking into account the operating status of thermal units,forecast information of RES,and load ***,after clarifying the logical relationship between the degree of RR scarcity and the values of assessment indicators,this paper establishes a mapping function between *** on this mapping function,a dynamic setting method for assessment indicators is *** the future,RES will generally be equipped with battery energy storage systems(BESSs).Reasonably utilizing BESSs to reduce the power deviation of RESs can increase the expected income of ***,this paper proposes a power curve optimization strategy for RESs considering self-owned *** case study demonstrates that the dynamic setting method of assessment indicators can increase the revenue of RESs while ensuring that the penalty fees paid by RESs to the grid are sufficient to cover the RR ***,the power curve optimization strategy can help RESs further increase income and fully utilize BESSs to reduce power deviation.

关键词： Renewable energy battery energy storage system(BESS) power curve assessment reserve service parameter setting

Zeros of Complete Symmetric Polynomials over Finite Fields

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Journal of Systems Science & Complexity 2024年第4期37卷 1772-1788页

作者： cao Wei School of Mathematics and Statistics Minnan Normal UniversityZhangzhou 363000China

Wan and Zhang(2021) obtained a nontrivial lower bound for the number of zeros of complete symmetric polynomials over finite fields,and proposed a problem whether their bound can be *** this paper,the author improves Wan-Zhang's bound from three *** proposed results are based on the estimates related to the number of certain permutations and the value sets of non-permutation polynomials associated to the complete symmetric *** the author believes that there are still possibilities to improve the bounds and hence Wan-Zhang's bound.

关键词： Complete symmetric polynomial finite field permutation polynomial value set

Bioinspired Closed-loop CPG-based Control of a Robotic Manta for Autonomous Swimming

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Journal of Bionic Engineering 2024年第1期21卷 177-191页

作者： Yiwei Hao Yonghui cao Yingzhuo cao Xiong Mo Qiaogao Huang Lei Gong Guang Pan Yong cao School of Marine Science and Technology Northwestern Polytechnical UniversityXi'an 710072China Unmanned Vehicle Innovation Center Ningbo Institute of NPUNingbo 315103China Key Laboratory of Unmanned Underwater Vehicle Technology of Ministry of Industry and Information Technology Xi'an 710072China

Fish in nature exhibit a variety of swimming modes such as forward swimming,backward swimming,turning,pitching,etc.,enabling them to swim in complex scenes such as coral *** is still difficult for a robotic fish to swim autonomously in a confined area as a real ***,we develop an untethered robotic manta as an experimental platform,which consists of two flexible pectoral fins and a tail fin,with three infrared sensors installed on the front,left,and right sides of the head to sense the surrounding *** generate multiple swimming modes of the robotic manta and online switching of different modes,we design a closed-loop Central Pattern Generator(CPG)controller based on distance information and use a combination of phase difference and amplitude of the CPG model to achieve stable and rapid adjustment of yaw *** verify the autonomous swimming ability of the robotic manta in complex scenes,we design an experimental scenario with a concave *** experimental results show that the robotic manta can achieve forward swimming,backward swimming,in situ turning within the concave obstacle,and finally exit from the area safely while relying on the perception of external obstacles,which can provide insight into the autonomous exploration of complex scenes by the biomimetic robotic ***,the swimming ability of the robotic manta is verified by field tests.

关键词： Biomimetic robotic manta Central Pattern Generator Closed-loop control Backward swimming

Pt nanodendrites with a PtIr alloy surface structure exhibit excellent stability toward acidic hydrogen evolution reaction

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Nano Research 2024年第6期17卷 4844-4849页

作者： Chang Liu Zongnan Wei Minna cao Rong cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

The development of effective and stable electrocatalysts for the hydrogen evolution reaction(HER)in acidic electrolytes is a significant *** this work,homogeneous Pt nanodendrites(Pt NDs)with a PtIr shell were successfully synthesized by a two-step wet chemical *** open three-dimensional(3D)dendritic structure exhibited exceptional electrocatalytic characteristics,exposing as many active sites as ***,by alloying Ir with Pt on the surface,catalytic activity was greatly enhanced while ensuring extremely high *** surface-enriched platinum nanodendritic catalysts(Pt@PtIr NDs)outperformed the control samples and the commercial *** acidic HER test,Pt@PtIr NDs had a lower overpotential(22 mV)than Pt NDs(26 mV)and commercial Pt/C(31 mV)at 10 mA/cm^(2),and the activity of Pt@PtIr NDs remained consistent even after undergoing a continuous durability test for at least 168 h,which was much superior to the performance of commercial Pt/C(10 h)under identical test *** study revealed that the application of 3D Pt dendritic metal alloys may offer a chance for the development of enhanced electrocatalysts in acidic HER.

关键词： Pt nanodendrites iridium high stability hydrogen evolution reaction alloy

Making the Complicated Simple:A Minimizing Carrier Strategy on Innovative Nanopesticides

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Nano-Micro Letters 2024年第10期16卷 31-46页

作者： Wenjie Shangguan Qiliang Huang Huiping Chen Yingying Zheng Pengyue Zhao Chong cao Manli Yu Yongsong cao Lidong cao State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193People's Republic of China College of Plant Protection China Agricultural UniversityBeijing 100193People's Republic of China State Key Laboratory of Element-Organic Chemistry Department of Chemical BiologyCollege of ChemistryNankai UniversityTianjin 300071People's Republic of China

The flourishing progress in nanotechnology offers boundless opportunities for agriculture,particularly in the realm of nanopesticides research and ***,concerns have been raised regarding the human and environmental safety issues stemming from the unrestrained use of non-therapeutic nanomaterials in *** is also important to consider whether the current development strategy of nanopesticides based on nanocarriers can strike a balance between investment and return,and if the complex material composition genuinely improves the efficiency,safety,and circularity of ***,we introduced the concept of nanopesticides with minimizing carriers(NMC)prepared through prodrug design and molecular self-assembly emerging as practical tools to address the current limitations,and compared it with nanopesticides employing non-therapeutic nanomaterials as carriers(NNC).We further summarized the current development strategy of NMC and examined potential challenges in its preparation,performance,and ***,we asserted that the development of NMC systems can serve as the innovative driving force catalyzing a green and efficient revolution in nanopesticides,offering a way out of the current predicament.

关键词： Nanopesticides Green agrochemicals Self-assembly Nanomaterial safety Sustainable development strategies

Recent Advances in Microbial Production of Terpenoids from Biomass-derived Feedstocks

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Chemical Research in Chinese Universities 2024年第1期40卷 20-28页

作者： cao Yujin XIAN Mo CAS Key Laboratory of Biobased Materials Qingdao Institute of BioEnergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101P.R.China Shandong Energy Institute Qingdao 266101P.R.China Qingdao New Energy Shandong Laboratory Qingdao 266101P.R.China

Terpenoids are a diverse class of natural products widely used as pharmaceuticals,perfumes,flavors,and ***,terpenoids are obtained from natural sources,such as plants,but their production is limited by the insufficiency of resources and low yields of *** production of terpenoids has emerged as a promising alternative due to that it is sustainable and easy to scale *** review aims to summarize recent advances in microbial production of terpenoids from inexpensive biomass-derived *** pathways and key enzymes involved in terpenoid biosynthesis are *** that can utilize low-cost lignocellulosic feedstocks for terpenoid production are *** challenges and prospects faced by microbial terpenoid production are *** believe that continuous progress in the fields of biomass transformation and synthetic biology will ultimately achieve industrial production of microbial terpenoids.

关键词： Terpenoid Microbial production Biomass-derived feedstock Metabolic pathway

Preparation and characterization of pH-responsive metal-polyphenol structure coated nanoparticles

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Food Science and Human Wellness 2024年第3期13卷 1303-1310页

作者： Qile Xia Yan Liang Ailing cao Yan cao Luyun Cai Key Laboratory of Post-Harvest Handling of Fruits Food Science InstituteZhejiang Academy of Agricultural SciencesHangzhou 310021China Ningbo Research Institute College of Biosystems Engineering and Food ScienceZhejiang UniversityNingbo 315100China School of Biological and Chemical Engineering Zhejiang Engineering Research Center for Intelligent Marine Ranch EquipmentNingboTech UniversityNingbo 315100China College of Food Science and Engineering Bohai UniversityJinzhou 121013China Hangzhou Customs District Hangzhou 310007China

In this paper,tannic acid(TA)and Fe~(3+)were added to form a layer of metal-polyphenol network structure on the surface of the nanoparticles which were fabricated by zein and carbon quantum dots(CQDs)encapsulating phlorotannins(PTN).pH-Responsive nanoparticles were prepared successfully(zein-PTN-CQDs-Fe-~Ⅲ).Further,the formation of composite nanoparticles was confirmed by a series of characterization *** zeta-potential and Fourier transform infrared spectroscopy data proved that electrostatic interaction and hydrogen bonding are dominant forces to form *** encapsulation efficiency(EE)revealed that metal-polyphenol network structure could improve the EE of *** analysis and differential scanning calorimetry experiment indicated the thermal stability of zein-PTN-CQDs-Fe~Ⅲnanoparticles increased because of metal-polyphenol network *** pH-responsive nanoparticles greatly increased the release rate of active substances and achieved targeted release.

关键词： Metal Phlorotannins Nanoparticles pH-Responsive Characterization

Sequential Inverse Optimal Control of Discrete-Time Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 608-621页

作者： Sheng cao Zhiwei Luo Changqin Quan the Graduate School of System Informatics Kobe University Kobe 657-8501Japan

This paper presents a novel sequential inverse optimal control(SIOC)method for discrete-time systems,which calculates the unknown weight vectors of the cost function in real time using the input and output of an optimally controlled discrete-time *** proposed method overcomes the limitations of previous approaches by eliminating the need for the invertible Jacobian *** calculates the possible-solution spaces and their intersections sequentially until the dimension of the intersection space decreases to *** remaining one-dimensional vector of the possible-solution space’s intersection represents the SIOC *** paper presents clear conditions for convergence and addresses the issue of noisy data by clarifying the conditions for the singular values of the matrices that relate to the possible-solution *** effectiveness of the proposed method is demonstrated through simulation results.

关键词： Inverse optimal control promised calculation step sequential calculation