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Correction to: State of the art of automatic disassembly of WEEE and perspective towards intelligent recycling in the era of Industry 4.0

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The International Journal of Advanced Manufacturing technology 2023年第7期128卷 2845-2845页

作者： Lu, Yingqi Pei, Weidi Peng, Kaiyuan School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai People’s Republic of China School of Mechanical Engineering Hefei University of Technology Hefei People’s Republic of China Key Laboratory of Green Design and Manufacturing of Mechanical Industry Hefei University of Technology Hefei China

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Synthesis of 2-Quinolinones via a Hypervalent Iodine(Ⅲ)-Mediated Intramolecular Decarboxylative Heck-Type Reaction at Room Temperature

Synthesis of 2-Quinolinones via a Hypervalent Iodine(Ⅲ)-Med...

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中国化学会第二届全国有机自由基化学会议

作者：樊化强张永强王卫 State Key Laboratory of Bioengineering Reactor Shanghai Key Laboratory of New Drug Design and School of Pharmacy East China University of Science and Technology

喹啉酮是一类重要的含氮杂环,表现出广泛的生物活性。邻烯基苯胺及其衍生物的内酰胺化是合成此类结构最为有效的方式之一。然而传统方法通常以剧毒的光气制品,一氧化碳或二氧化碳为羰基源,需要在高温条件下使用昂贵而具有毒性的过渡金... 详细信息

喹啉酮是一类重要的含氮杂环,表现出广泛的生物活性。邻烯基苯胺及其衍生物的内酰胺化是合成此类结构最为有效的方式之一。然而传统方法通常以剧毒的光气制品,一氧化碳或二氧化碳为羰基源,需要在高温条件下使用昂贵而具有毒性的过渡金属或强碱介导反应的进行,存在反应条件苛刻,官能团兼容性差的缺点,不利于进一步工业放大合成。鉴于此,以邻烯基苯草氨酸为原料,我们发展了一类三价碘介导的分子内脱羧Heck反应,通过内酰胺化的方式,在无金属条件下,实现了多样性喹啉-2(1H)-酮结构的高效构建。该反应体系绿色温和,以易于制备的草胺酸为羰基源,表现出优异的化学选择性和官能团兼容性。通过进一步研究,我们初步阐明了环张力诱导碘氧键断裂的自由基脱羧机制,为设计新的三价碘介导自由基脱羧偶联反应指明了方向。

关键词：官能团 Mediated Intramolecular Decarboxylative Heck-Type Reaction at Room Temperature Synthesis of 2-Quinolinones via a Hypervalent Iodine

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Preparation and properties of new nano hybrid crude oil pour point depressant

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Colloids and Surfaces A: Physicochemical and Engineering Aspects 2025年 723卷

作者： Manping Yang Jiapei Li Jingkai Shi Daxin Zhou Chao Yang Bingfan Li Tifeng Jiao School of Vehicle and Energy Yanshan University Qinhuangdao 066004 China CNPC Offshore Engineering (QINGDAO) Co Ltd 266555 China Daqing Oilfield Design Inst Co Ltd Daqing 163000 China Technology Inspection Center of Shengli Oilfield SINOPEC Dongying 257000 China State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China

In order to solve the problem of crude oil production and long-distance transportation caused by wax deposition, a series of new nano-hybrid pour point depressants were prepared by intercalation of ethylene-vinyl acetate copolymer grafted with maleic anhydride into nano-bentonite. EVA was chemically grafted by solution blending, and nano-bentonite was improved to make it amphiphilic. The experimental results show that when the mass ratio of BT to EVAM is 1:4, the pour point depression effect is the best. The composite system can significantly inhibit the growth and agglomeration of wax crystals, and the effect of reducing the pour point of crude oil is more than 183 % of that of the original commercial pour point depressant. The synergistic mechanism of nanosheet barrier and polar group adsorption was explored by various characterization methods. It was confirmed that the NPPD at an appropriate dose was more effective than EVAM in modifying the wax crystal morphology, preventing its aggregation and improving the low temperature fluidity of crude oil. In addition, the composite pour point depressant is liquid at 25℃, which reduces storage and transportation costs and safety risks. This study provides a new idea for the development of efficient and environmentally friendly crude oil rheology improvers.

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Nonvolatile ferroelectric control of topological states in two-dimensional heterostructures

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Physical Review B 2020年第23期102卷 235403-235403页

作者： Hua Bai Xinwei Wang Weikang Wu Pimo He Zhu'an Xu Shengyuan A. Yang Yunhao Lu Zhejiang Province Key Laboratory of Quantum Technology and Device Department of Physics Zhejiang University Hangzhou 310027 China State Key Laboratory of Silicon Materials and School of Materials Science and Engineering Zhejiang University 38 Zheda Road Hangzhou 310027 P. R. China Research Laboratory for Quantum Materials Singapore University of Technology and Design Singapore 487372 Singapore

Quantum spin Hall (QSH) insulator materials feature topologically protected edge states that can drastically reduce dissipation and are useful for the next-generation electronics. However, the nonvolatile control of topological edge state is still a challenge. In this paper, based on first-principles calculations, the switchable topological states are found in the van der Waals (vdW) heterostructures consisting of two-dimensional (2D) Bi(111) bilayer (BL) and α−In2Se3 by reversing the electric polarization of the ferroelectric α−In2Se3. The topological switching results from the different charge transfer associated with the two opposite polarization states of α−In2Se3. This new topological switching mechanism has the unique advantages of being fully electrical as well as nonvolatile. Our finding provides an unprecedented approach to realize ferroelectric control of topological states in 2D materials, which will have great potential for applications in topological nanoscale electronics.

关键词： Edge states Electronic structure Ferroelectricity First-principles calculations Topological materials Topological phase transition

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Structural Damage Semantic Segmentation Using Dual-Network Fusion

Structural Damage Semantic Segmentation Using Dual-Network F...

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作者： Lingrui Mei Jiaqi Yin Donghao Zhou Kai Kang Qiang Zhang State Key Laboratory of Vehicle NVH and Safety Technology China Automotive Engineering Research Institute Chongqing University Chongqing Communications Planning Survey and Design Institute The Hong Kong University of Science and Technology

Road cracks seriously affect road life and driving safety, and road crack segmentation has been a key task in many research fields and *** of existing road crack datasets are relatively homogeneous, most datasets only have local crack images taken from a single perspective, and the images lack complex interference pattern other than the cracks and the road ***, real-world images of roads are much more complex, and roads may have other dark patterns that interfere with crack segmentation. Perspective and lighting conditions may also be different between every image in the dataset,which makes many road crack segmentation methods extremely low accuracy and severely affects the generalization ability of the semantic segmentation model, while many applications require higher precision rather than recall. In this paper, two methods are proposed to improve the accuracy: augmenting complex patterns in road images and the fusion of classification networks. The methods greatly improve the performance of road crack segmentation.

关键词： image Structural Damage Semantic Segmentation Using Dual-Network Fusion

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Theoretical and computational exploration of electronic structure, optical properties, open circuit voltage, and toxicity of perovskites solar Cell:(Cs₂SiX₆, X = Cl, Br, and I)

Hybrid Advances

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Hybrid Advances 2023年 4卷

作者： Ali, Md. Hazrat Khatun, Halima Khan, M.S.S. Roy, Shuva Roy, Shubha Hossain, Ridoy Robiul Mia, M. Rahman Khan, Ashiqur Arfin Hussain, Syed Bayejid Hossen, M. Khan, Md. Barkat Ullah Kaiyum, Abdul Karim, Md Tauhidul Chakma, Unesco Kumer, Ajoy Department Electrical and Electronic Engineering European University of Bangladesh Gabtoli Dhaka 1216 Bangladesh Department of Physics Jahangirnagar University Savar Dhaka Bangladesh Department Civil Engineering European University of Bangladesh Gabtoli Dhaka 1216 Bangladesh Laboratory of Computational Research for Drug Design and Material Science Department of Chemistry College of Arts and Sciences IUBAT-International University of Business Agriculture and Technology 4 Embankment Drive Road Sector 10 Uttara Model Town Dhaka 1230 Bangladesh School of Electronic Science and Engineering Southeast University Nanjing China

Perovskites are presently being considered as a feasible choice for hole-transport materials in photovoltaic devices. One material that stands out among the options is Cs2SiX6, where X indicates Cl, Br, and I. This ma... 详细信息

Perovskites are presently being considered as a feasible choice for hole-transport materials in photovoltaic devices. One material that stands out among the options is Cs₂SiX₆, where X indicates Cl, Br, and I. This material is of special interest due to its potential as a lead-free alternative, offering a variety of halide options. Moreover, several experimental inquiries have exhibited favorable outcomes;nevertheless, their theoretical or computational framework is limited and insufficient. As a result, the present investigation has opted for the crystal Cs₂SiX₆ and synthesized Cs₂SiX₆, Cs₂SiCl₆, Cs₂SiBr₆ and Cs₂SiI₆ to examine their electronic structures and optical properties using the DFT functional. The electronic structure of Cs₂SnBr₆, was calculated using GGA with PBE functional, yielding a band gap of 2.434 eV. It should be noted that the experimental value of Cs₂SnBr₆ was 2.450 eV. Furthermore, the band gaps of Cs₂SiCl₆, Cs₂SiBr₆, and Cs₂SiI₆ were calculated by GGA with PBE to be 1.540 eV, 1.291 eV, and 0.261 eV, respectively. In this study, various pseudopotential techniques are employed to investigate the electrical structures. Five different densities functional theory (DFT) functionals are utilized to determine the most accurate functional. Additionally, the study focuses on the LDA, a unique junction photovoltaic material. In addition, the six optical properties, specifically absorption, reflection, refractive index, conductivity, dielectric function, and loss function, are calculated to provide additional understanding of material qualities in the presence of visual evidence. The utilization of the Density of States (DOS) and the Partial Density of States (PDOS) was employed in order to calculate the electronic st

关键词： Band gap Density of states Dielectric function Perovskite Photovoltaic devices

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Theoretical design of all-carbon networks with intrinsic magnetism

arXiv

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arXiv 2021年

作者： Gao, Yan Feng, Xiaolong Gong, Ben-Chao Zhong, Chengyong Yang, Shengyuan A. Liu, Kai Lu, Zhong-Yi Department of Physics Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices Renmin University of China Beijing100872 China Research Laboratory for Quantum Materials Singapore University of Technology and Design Singapore487372 Singapore Institute for Advanced Study Chengdu University Chengdu610106 China Center for Quantum Transport and Thermal Energy Science School of Physics and Technology Nanjing Normal University Nanjing210023 China

To induce intrinsic magnetism in the nominally nonmagnetic carbon materials containing only s and p electrons is an intriguing yet challenging task. Here, based on first-principles electronic structure calculations, we propose a universal approach inspired by Ovchinnikov's rule to guide us the design of a series of imaginative magnetic all-carbon structures. The idea is to combine the differently stacked graphene layers via the acetylenic linkages (-C≡C-) to obtain a class of two-dimensional (2D) and three-dimensional (3D) carbon networks. With first-principles electronic structure calculations, we confirm the effectiveness of this approach via concrete examples of double-layer ALBG-C14, triple-layer ALTG-C22, and bulk IALG-C30. We show that these materials are antiferromagnetic (AFM) semiconductors with intralayer Néel and interlayer AFM couplings. According to the above idea, our work not only provides a promising design scheme for magnetic all-carbon materials, but also can apply to other π-bonding network systems. Copyright © 2021, The Authors. All rights reserved.

关键词： Magnetism

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Pervasive Machine Learning for Smart Radio Environments Enabled by Reconfigurable Intelligent Surfaces

arXiv

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arXiv 2022年

作者： Alexandropoulos, George C. Stylianopoulos, Kyriakos Huang, Chongwen Yuen, Chau Bennis, Mehdi Debbah, Mérouane The Department of Informatics and Telecommunications National and Kapodistrian University of Athens Panepistimiopolis Ilissia Athens15784 Greece The Technology Innovation Institute 9639 Masdar City Abu Dhabi United Arab Emirates The College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China The International Joint Innovation Center Zhejiang University Haining314400 China The Zhejiang Provincial Key Laboratory of IPCAN Hangzhou310027 China Pillar Singapore University of Technology and Design 487372 Singapore Centre for Wireless Communications University of Oulu Oulu90014 Finland The Technology Innovation Institute The Mohamed Bin Zayed University of Artificial Intelligence Masdar City Abu Dhabi9639 United Arab Emirates

The emerging technology of Reconfigurable Intelligent Surfaces (RISs) is provisioned as an enabler of smart wireless environments, offering a highly scalable, low-cost, hardware-efficient, and almost energy-neutral solution for dynamic control of the propagation of electromagnetic signals over the wireless medium, ultimately providing increased environmental intelligence for diverse operation objectives. One of the major challenges with the envisioned dense deployment of RISs in such reconfigurable radio environments is the efficient configuration of multiple metasurfaces with limited, or even the absence of, computing hardware. In this paper, we consider multi-user and multi-RIS-empowered wireless systems, and present a thorough survey of the online machine learning approaches for the orchestration of their various tunable components. Focusing on the sum-rate maximization as a representative design objective, we present a comprehensive problem formulation based on Deep Reinforcement Learning (DRL). We detail the correspondences among the parameters of the wireless system and the DRL terminology, and devise generic algorithmic steps for the artificial neural network training and deployment, while discussing their implementation details. Further practical considerations for multi-RIS-empowered wireless communications in the sixth Generation (6G) era are presented along with some key open research challenges. Differently from the DRL-based status quo, we leverage the independence between the configuration of the system design parameters and the future states of the wireless environment, and present efficient multi-armed bandits approaches, whose resulting sum-rate performances are numerically shown to outperform random configurations, while being sufficiently close to the conventional Deep Q-Network (DQN) algorithm, but with lower implementation complexity. © 2022, CC BY-NC-ND.

关键词： Backpropagation

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Experimental extraction of neutron resonance parameters at 0.1–300 eV for Yb168

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Physical Review C 2025年第5期111卷 054607-054607页

作者： Ya-Ju Chen (陈雅菊) Xin-Xiang Li (李鑫祥) Wei Jiang (蒋伟) Jie Ren (任杰) Wen Xie (谢文) Hong-Wei Wang (王宏伟) Gong-Tao Fan (范功涛) Long-Xiang Liu (刘龙祥) Yue Zhang (张岳) Zi-Ang Lin (林子昂) Ting Jiang (江婷) Zhi-Cai Li (李志才) Kai-Jun Luo (罗凯军) Xiao-Ming Shi (施小明) Xian-Kai Li (黎先锴) Zong-Wei Cao (曹宗威) Gao-Le Yang (杨高乐) Zhen-Dong An (安振东) Bing Jiang (姜炳) Wen Luo (罗文) School of Nuclear Science and Technology University of South China Hengyang 421001 China Key Laboratory of Advanced Nuclear Energy Design and Safety Ministry of Education Hengyang 421001 China Institute of High Energy Physics Chinese Academy of Sciences Beijing100049China China Spallation Neutron Source Dongguan 523803 China China Institute of Atomic Energy Beijing 102413 China Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201210 China School of Physics and Astronomy Sun Yat-sen University Zhuhai 519082 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

The (n,γ) cross section of the nuclide Yb168, which is one of 35 p-nuclei, plays an important role in nuclear astrophysics network calculations. The Yb168 resonance parameters, Γγ and Γn, show significant discrepancies between these evaluated nuclear data libraries, while existing experimental data remain insufficient to resolve them. In this study, the (n,γ) yield of Ybnat is measured at the Back-n facility of the Chinese Spallation Neutron Source using the time-of-flight method. The Γγ and Γn parameters of Yb168 are extracted by the multilevel R-matrix Bayesian code sammywithin the energy range of 0.1–300 eV. Both the Γγ and Γn parameters at three resonance peaks of 0.58, 22.53, and 27.17 eV are obtained successfully. Among them, the Γγ value at 27.17 eV is experimentally extracted to be 65.88 ± 5.80 meV for the first time. These resonance results are further compared with the available evaluated and experimental data. It is found that the extracted Γγ values are in good agreement with the nuclear data libraries ENDF/B-VIII.0, JENDL-4.0, BROND-3.1, and JEFF-3.3. Meanwhile, the extracted Γn value at 0.58 eV is consistent with TENDL-2019, whereas the Γn values at two other resonance peaks are different from the existing data. These findings enrich the experimental data of the Yb168 neutron capture resonance and emphasize the importance of selecting appropriate nuclear data libraries.

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High-sensitivity transition-edge-sensed bolometers: improved speed and characterization with AC and DC bias

arXiv

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arXiv 2023年

作者： Foote, Logan Audley, Michael D. Bradford, Charles de Lange, Gert Echternach, Pierre Fixsen, Dale J. Hui, Howard Kenyon, Matthew Nguyen, Hien O'Brient, Roger Sharp, Elmer H. Staguhn, Johannes G. van der Kuur, Jan Zmuidzinas, Jonas Department of Physics California Institute of Technology PasadenaCA91125 United States Jet Propulsion Laboratory California Institute of Technology PasadenaCA91125 United States SRON Netherlands Institute for Space Research Leiden2333CA Netherlands Observational Cosmology Lab Code 665 NASA Goddard Space Flight Center GreenbeltMD20771 United States CRESST University of Maryland College ParkMD20742 United States Alora Science & Design LLC 7007 Leesville Blvd SpringfieldVA22151 United States The William H. Miller III Department of Physics & Astronomy Johns Hopkins University 3400 North Charles Street BaltimoreMD21218 United States

We report on efforts to improve the speed of low-G far-infrared transition-edged-sensed bolometers. We use a fabrication process that does not require any dry etch steps to reduce heat capacity on the suspended device and measure a reduction in the detector time constant. However, we also measure an increase in the temperature-normalized thermal conductance (G), and a corresponding increase in the noise-equivalent power (NEP). We employ a new near-IR photon-noise technique using a near-IR laser to calibrate the frequency-domain multiplexed AC system and compare the results to a well-understood DC circuit. We measure an NEP white noise level of 0.8 aW/rtHz with a 1/f knee below 0.1 Hz and a time constant of 3.2 ms. Copyright © 2023, The Authors. All rights reserved.

关键词： Specific heat

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