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Ultrafast micro/nano-manufacturing of metastable materials for energy

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National science Review 2024年第4期11卷 283-298页

作者： Xiaoya Cui Yanchang Liu Yanan Chen School of Materials science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) and Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University ministry of education key laboratory of Protein sciences School of Life SciencesTsinghua University

The structural engineering of metastable nanomaterials with abundant defects has attracted much attention in energy-related fields. The high-temperature shock(HTS) technique, as a rapidly developing and advanced synthesis strategy, offers significant potential for the rational design and fabrication of high-quality nanocatalysts in an ultrafast, scalable, controllable and eco-friendly way. In this review, we provide an overview of various metastable micro-and nanomaterials synthesized via HTS, including single metallic and bimetallic nanostructures, high entropy alloys, metal compounds(e.g. metal oxides) and carbon nanomaterials. Note that HTS provides a new research dimension for nanostructures, i.e. kinetic modulation. Furthermore, we summarize the application of HTS—as supporting films for transmission electron microscopy grids—in the structural engineering of 2D materials, which is vital for the direct imaging of metastable materials. Finally, we discuss the potential future applications of high-throughput and liquid-phase HTS strategies for non-equilibrium micro/nano-manufacturing beyond energy-related *** is believed that this emerging research field will bring new opportunities to the development of nanoscience and nanotechnology in both fundamental and practical aspects.

关键词： high-temperature shock technique defect engineering metastable phase kinetic modulation non-equilibrium micro/nano-manufacturing

Grain boundary-induced drastic sensing performance enhancement of Fe_(2)O_(3) gas sensors for acetone

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Rare Metals 2024年第9期43卷 4412-4424页

作者： Tian-Jun Hu Yi-Fan Li Yu-Zhu Tian Ying Wang Ya-Ru Chen Jun-Ming Zhang Er-Gui Luo Jian-Feng Jia key laboratory of Magnetic Molecules&Magnetic information Materials ministry of education School of Chemical and Material ScienceShanxi Normal UniversityTaiyuan 030032China

Exploring the structure-activity relationship between the performance of gas sensors and the structure of semiconductor metal oxide(SMO)nanomaterials is crucial for understanding and designing gas-sensing materials and overcoming the application limitations of SMO-based gas *** of a single SMO microstructure provides a promising solution to address this scientific problem due to its controllable *** this study,we control the grain boundary(GB)density of Fe_(2)O_(3)nanomaterials using a simple solvothermal *** have similar chemical compositions and crystal phases,providing an ideal platform for studying the influence of the GB density on the gas-sensing ***-sensing tests showed that the Fe_(2)O_(3)-1 sensor with medium GB density and the Fe_(2)O_(3)-2 sensor with high GB density had higher sensitivity and selectivity than the Fe_(2)O_(3)-0 sensors with low GB density before reaching the optimal operating ***,when the GB density increased,the response to acetone decreased slightly,whereas the optimal operating temperature *** work highlights the unique performance of the GB density in enhancing the gas sensitivity of a single SMO.

关键词： Semiconductor metal oxide(SMO) Grain boundary(GB)density Oxygen adsorption Charge transfer Gas sensors

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Optimized parameters of downhole all-metal PDM based on genetic algorithm

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Petroleum science 2024年第4期21卷 2663-2676页

作者： Jia-Xing Lu Ling-Rong Kong Yu Wang Chao Feng Yu-Lin Gao China University of geosciences (Beijing) key laboratory on Deep geo-Drilling Technology of ministry of Natural Resources

Currently, deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power motors. The all-metal positive displacement motor, known for its robust performance, is a critical choice for such drilling. The dimensions of the PDM are crucial for its performance output. To enhance this, optimization of the motor's profile using a genetic algorithm has been undertaken. The design process begins with the computation of the initial stator and rotor curves based on the equations for a screw cycloid. These curves are then refined using the least squares method for a precise fit. Following this, the PDM's mathematical model is optimized, and motor friction is assessed. The genetic algorithm process involves encoding variations and managing crossovers to optimize objective functions, including the isometric radius coefficient, eccentricity distance parameter,overflow area, and maximum slip speed. This optimization yields the ideal profile parameters that enhance the motor's output. Comparative analyses of the initial and optimized output characteristics were conducted, focusing on the effects of the isometric radius coefficient and overflow area on the motor's performance. Results indicate that the optimized motor's overflow area increased by 6.9%, while its rotational speed reduced by 6.58%. The torque, as tested by Infocus, saw substantial improvements of38.8%. This optimization provides a theoretical foundation for improving the output characteristics of allmetal PDMs and supports the ongoing development and research of PDM technology.

关键词： Positive displacement motor Genetic algorithm Profile optimization Matlab programming Overflow area

Cross-linkedα-amylase aggregates on Fe3O4 magnetic nanoparticles modified with polydopamine/polyethyleneimine for efficient hydrolysis of starch

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Particuology 2024年第7期90卷 98-105页

作者： Jiandong Cui Xiuming Tang Qingqing Ma Yuyan Chang Qunli Zhang Shiru Jia State key laboratory of Food Nutrition and Safety Laboratory of Industrial Fermentation MicrobiologyMinistry of EducationTianjin University of Science and TechnologyTianjin 300457China key laboratory of Biomass Chemical Engineering of ministry of education Zhejiang UniversityHangzhou 310027China

In this workα-amylase was immobilized on magnetic Fe3O4 nanoparticles with polyethylenimine(PEI)/polydopamine(PDA)coating or 3-aminopropyl triethoxysilane(APTES)for the first time via adsorption–precipitation–*** with the freeα-amylase,the resultant magnetic cross-linkedα-amylase aggregates(PEI/PDA-M-CLEAs and N-M-CLEAs)exhibited excellent thermal and storage stability as well as pH *** storage at 25°C for 60 days,freeα-amylase only retained 60%of its initial activity,while PEI/PDA-M-CLEAs and N-M-CLEAs retained 80%and 78%of their initial activities,***,N-M-CLEAs and PEI/PDA-M-CLEAs showed good *** 6 repeated uses,PEI/PDA-M-CLEAs and N-M-CLEAs still maintained 65%and 62%of their initial activities,***,PEI/PDA-M-CLEAs and N-M-CLEAs exhibited higher starch hydrolysis efficiency than freeα-*** maximum dextrose equivalent(DE)values of starch hydrolysis by PEI/PDA-M-CLEAs and N-M-CLEAs reached 29.24%and 28.79%within 90 min,***,the maximum DE values of starch hydrolysis by the freeα-amylase was only 27.89%even in 150 *** magnetic cross-linkedα-amylase aggregates could be introduced as effective biocatalyst for industrial applications in production of maltose syrups.

关键词： α-amylase Magnetic nanoparticles Functional modification Magnetic cross-linked enzyme aggregates Hydrolysis of starch

Gate regulated near-infrared photodetector utilizing interlayer excitons for MoS2/CrPS4 heterojunction

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science China(information sciences) 2024年第3期67卷 315-316页

作者： Guoliang XU Chao HE Donghong SHI Danmin LIU Wenjie DENG Jingzhen LI Xingtao AN Yongzhe ZHANG Hebei Provincial key laboratory of Photoelectric Control on Surface and Interface College of ScienceHebei University of Science and Technology key laboratory of Advanced Functional Materials Ministry of EducationFaculty of Materials and ManufacturingBeijing University of Technology key laboratory of Optoelectronics Technology Ministry of EducationFaculty of Information TechnologyBeijing University of Technology

Excitons play an important role as interconnect in the optical and optoelectronic response and have attracted much attention for understanding the physical matters behind excitons [1, 2]. Excitons in atomically thin transition metal dichalcogenides semiconductors(TMDs) often trap an electron(X-) or a hole(X+) to form so-called trions,

关键词： Excitons

Multi-Objective Optimization Based on Life Cycle Assessment for Hybrid Solar and Biomass Combined Cooling,Heating and Power System

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Journal of Thermal science 2024年第3期33卷 931-950页

作者： LIU Jiejie LI Yao MENG Xianyang WU Jiangtao key laboratory of Thermo-Fluid science and Engineering Ministry of EducationXi’an Jiaotong UniversityXi’an710049China

The complementary of biomass and solar energy in combined cooling,heating and power(CCHP)system provides an efficient solution to address the energy crisis and environmental *** work aims to propose a multi-objective optimization model based on the life cycle assessment(LCA)method for the optimal design of hybrid solar and biomass *** life-cycle process of the poly-generation system is divided into six phases to analyze energy consumption and greenhouse gas *** comprehensive performances of the hybrid system are optimized by incorporating the evaluation criteria,including environmental impact in the whole life cycle,renewable energy contribution and economic *** non-dominated sorting genetic algorithmⅡ(NSGA-Ⅱ)with the technique for order preference by similarity to ideal solution(TOPSIS)method is employed to search the Pareto frontier result and thereby achieve optimal *** developed optimization methodology is used for a case study in an industrial *** results indicate that the best performance from the optimized hybrid system is reached with the environmental impact load reduction rate(EILRR)of 46.03%,renewable energy contribution proportion(RECP)of 92.73%and annual total cost saving rate(ATCSR)of35.75%,*** comparing pollutant-eq emissions of different stages,the operation phase emits the largest pollutant followed by the phase of raw material ***,this study reveals that the proposed multi-objective optimization model integrated with LCA method delivers an alternative path for the design and optimization of more sustainable CCHP system.

关键词： combined cooling heating and power system solar-biomass multi-objective optimization life cycle assessment optimal design

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Effect of nanofillers with different energy levels on the electrical properties of epoxy‐based nanocomposites

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High Voltage 2024年第4期9卷 948-956页

作者： Ning Guo Cailing Chen Guangwei Zhang Rongsheng Sun Yulong Wang Junguo Gao key laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and TechnologyHarbinChina

The authors investigate the effects of nanofillers with varying band‐gap energies on the space charge properties,breakdown field strength,and bulk resistivity of epoxy(EP)‐based ***,the molecular orbital distribution of both the epoxy resin and nanofillers were examined through density functional *** results indicate that the space charge accumulation within silicon dioxide/EP and germanium oxide/EP is reduced,leading to a more uniformly distributed electric field intensity within the specimen when compared to *** a result,both materials exhibit improved AC breakdown field strength and volume ***,the amount of charge accumulated within tin dioxide/EP is higher,resulting in lower breakdown field strength than *** lowest unoccupied molecular orbital and the highest occupied molecular orbital energy level differences between epoxy and nanofillers introduce electron traps and hole traps at the interface,forming interfacial traps that affect the space charge distribution within the specimen,as well as the trap energy levels within the *** the experimental results,shallow traps promote space charge accumulation and reduce the breakdown field strength,while deep traps have the opposite effect.

关键词： energy resistivity occupied

Visualizing extended defects at the atomic level in a Bi2Sr2CaCu2O8+δ superconducting wire

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Chinese Physics B 2024年第9期33卷 47-51页

作者：胡柯钧王帅李泊玉刘影葛炳辉宋东升 information Materials and Intelligent Sensing laboratory of Anhui Province Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Institutes of Physical Science and Information Technology Anhui University

The microstructure significantly influences the superconducting ***,the defect structures and atomic arrangements in high-temperature Bi2Sr2CaCu2O8+δ（Bi-2212） superconducting wire are directly characterized via stateof-the-art scanning transmission electron *** oxygen atoms are observed in both the charge reservoir layers and grain boundaries in the doped *** phases with varied numbers of CuO2layers are found,and twist interfaces with different angles are *** study provides insights into the structures of Bi-2212 wire and lays the groundwork for guiding the design of microstructures and optimizing the production methods to enhance superconducting performance.

关键词： defect microstructure scanning transmission electron microscopy superconductor

Polyolefin vitrimers bearing acetoacetate functionality

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science China Chemistry 2024年第11期67卷 3861-3867页

作者： Zihao Wang Yue Liu Wenmin Pang Ao Chen Min Chen Chinese Academy of sciences (CAS) key laboratory of Soft Matter Chemistry Department of Polymer Science and Engineering University of Science and Technology of China Institutes of Physical science and information Technology Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education Anhui University

Polyolefin vitrimers are polymer networks bearing reversible covalent crosslinking points, enabling them to be reprocessed and recycled. In this contribution, a series of polyolefin vitrimers were designed based on the acetoacetate-functionalized polyolefin copolymers, which were produced through the direct copolymerization of ethylene with polar comonomers using a phosphinesulfonate palladium catalyst. The pendant acetoacetate group could mediate several characteristic reactions, such as the Michael addition reaction, ketone-amine condensation and metal coordination reaction. As such, structurally adjustable polyolefin vitrimers can be accessed by introducing various dynamic crosslinking bonds, including disulfide exchange, transamination of vinylogous urethane and labile metal coordination bond. The utilization of different crosslinking reactions and the mole ratio of crosslinkers significantly impact the material properties of the resultant polymers. Specifically, the generated polyolefin vitrimers demonstrated excellent reprocessability and closed-loop recycling properties. The study in this work provides an efficient strategy to access various polyolefin vitrimers.

关键词： polyolefin vitrimers acetoacetate group polar monomer olefin copolymerization