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Rare Metals 2024年第10期43卷 5202-5215页

作者： Zhong-Hua Li Liang Liu Xin You Jian-Hong Yi Rui Bao Ming-Yi Zhu Song Lu Jun-Jun Pai faculty of Materials science and Engineering Kunming University of Science and Technology Key Laboratory of advanced Materials of Yunnan Province Kunming University of Science and Technology

Strengthening interface bonding between boron nitride nanosheets(BNNS) and copper matrix is an essential prerequisite for exploiting a new generation of copper matrix composites(CMCs) with high strength and wear resistance. Herein, BNNS/Cu composites were fabricated by the powder metallurgy route, matrix-alloying(adding 1.0 wt% Ti) strategy was adopted to improve the interfacial wettability and strengthen interface adhesion. A typical "sandwich"-like multiply interface structure involving TiN transition layers, BNNS and Cu matrix had been well constructed through the rational heat treatment(900℃for 120 min). Additionally, nano-sized TiB whisker was in situ formed in the vicinity of the interface, it had linked the BNNS-Cu-TiN multiply interface, which played a role of "threading the needle" and significantly strengthened the multi-interfaces bonding. This specific interface structure was finely characterized, and the formation mechanism of solid-state interfacial reaction feature was proposed. The results demonstrated that the ultimate tensile strength(UTS) of BNNS/Cu-(Ti)-900℃ increased from 248 to 530 MPa(increased by 114%), and the coefficient of friction(COF) decreased from 0.51 to 0.28 than pure Cu. This work highlights the importance of interface configuration design, which contributes to the development of CMCs with prominent comprehensive properties.

关键词： Boron nitride nanosheets Copper matrix composites Interface structure Mechanical and frictional properties

Attaining synergetic equilibrium of electrical conductivity and tensile strength in GQDs@GN/Cu composites through multi-scale intragranular and intergranular reinforcements

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Rare Metals 2024年第1期43卷 366-379页

作者： Shuang-Yin Zhang Liang Liu Rui Bao Jian-Hong Yi Sheng-Da Guo faculty of Materials science and Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of advanced Materials of Yunnan Province Kunming University of Science and TechnologyKunming 650093China faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

The configuration and quality of reinforcements, as well as the robustness of interfacial bonding,holding a critical significance in determining the concurrence between electrical conductivity and mechanical strength in metal matrix composites. In this study, citric acid was employed as the precursor for synthesizing multiscale carbon nanomaterials(graphene quantum dots and graphene, abbreviated as GQDs and GN). The GQDs@GN/Cu composites were fabricated through a segmented ball milling process in conjunction with subsequent spark plasma sintering(SPS). The intragranular GQDs and intergranular GQDs@GN had synergistically reinforced Cu composites through Orowan strengthening, load transfer strengthening and refinement strengthening. Furthermore,the robust interface bonding between GQDs@GN and Cu effectively mitigated interfacial impedance stemming from electron-boundary scattering. The yield strength and ultimate tensile strength of the GQDs@GN/Cu composites were recorded as 270 and 314 MPa, respectively, representing an improvement of 92 and 28% over pure Cu, while maintaining electrical conductivity at a level comparable to that of pure Cu. This study advances the understanding of the possibility of realizing a synergistic compatibility between electrical conductivity and mechanical strength in Cu composites.

关键词： Cu matrix composites Interface bonding Mechanical property Graphene quantum dots(GQDs) Electrical conductivity

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Low-temperature graphitization of lignin via Co-assisted electrolysis in molten salt

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Green Energy & Environment 2024年第9期9卷 1449-1458页

作者： Shijie Li Wei-Li Song Xue Han Qingqing Cui Yan-li Zhu Shuqiang Jiao Institute of advanced Structure technology Beijing Institute of Technology State Key Laboratory of advanced Metallurgy University of Science and Technology Beijing State Key Laboratory of Explosion science and technology Beijing Institute of Technology

The ever-growing energy demand and environmental issues have stimulated the development of sustainable energy ***,an efficient and environmentally friendly electrochemical transformation technology was proposed to prepare highly graphitized carbon materials from an abundant natural resource-lignin （LG）.The preparation process mainly includes pyrolytic carbonization of raw LG material and electrochemical conversion of amorphous carbon ***,with the assistance of Co catalyst,the graphitization degree of the products was significantly improved,in which the mechanism was the removal of heteroatoms in LG and the rearrangement of carbon atoms into graphite ***,tunable microstructures （nanoflakes） under catalytic effects could also be observed by controlling the electrolytic *** with the products CN1 （without catalyst） and CN5 （with 10%catalyst）,the specific surface area are 158.957 and202.246 m2g-1,*** used as the electrode material for lithium-ion batteries,CN5 delivered a competitive specific capacity of～350 m Ah g-1（0.5 C） compared with commercial *** strategy proposed in this work provides an effective way to extract value-added graphite materials from lignin and can be extended to the graphitization conversion of any other amorphous carbon precursor materials.

关键词： Lignin Graphitic carbon Electrochemical conversion Lithium-ion batteries

Deep Guided Attention Network for Joint Denoising and Demosaicing in Real Image

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Chinese Journal of Electronics 2024年第1期33卷 303-312页

作者： Tao ZHANG Ying FU Jun ZHANG School of Computer science and technology Beijing Institute of Technology advanced Reasearch Institute of Multidisciplinary science Beijing Institute of Technology

Denoising(DN) and demosaicing(DM) are the first crucial stages in the image signal processing pipeline. Recently, researches pay more attention to solve DN and DM in a joint manner, which is an extremely undetermined inverse problem. Existing deep learning methods learn the desired prior on synthetic dataset, which limits the generalization of learned network to the real world data. Moreover, existing methods mainly focus on the raw data property of high green information sampling rate for DM, but occasionally exploit the high intensity and signalto-noise(SNR) of green channel. In this work, a deep guided attention network(DGAN) is presented for real image joint DN and DM(JDD), which considers both high SNR and high sampling rate of green information for DN and DM, respectively. To ease the training and fully exploit the data property of green channel, we first train DN and DM sub-networks sequentially and then learn them jointly, which can alleviate the error accumulation. Besides, in order to support the real image JDD, we collect paired raw clean RGB and noisy mosaic images to conduct a realistic dataset. The experimental results on real JDD dataset show the presented approach performs better than the state-of-the-art methods, in terms of both quantitative metrics and qualitative visualization.

关键词： Training Visualization Inverse problems Green products Noise reduction Pipelines Signal processing

Enhanced ferroelectric and improved leakage of BFO-based thin films through increasing entropy strategy

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2263-2273页

作者： Dongfei Lu Guoqiang Xi Hangren Li Jie Tu Xiuqiao Liu Xudong Liu Jianjun Tian Linxing Zhang Institute for advanced Materials technology University of Science and Technology BeijingBeijing 100083China

BiFeO_(3)(BFO)has received considerable attention as a lead-free ferroelectric film due to its large theoretical remnant ***,BFO suffers from a large leakage current,resulting in poor ferroelectric ***,the sol-gel method was used to deposit a series of BFO-based thin films on fluorine-doped tin oxide substrates,and the effects of the substitution of the elements Co,Cu,Mn(B-site)and Sm,Eu,La(A-site)on the crystal structure,ferroelectricity,and leakage current of the BFO-based thin films were *** confirmed that lattice distortion by X-ray diffraction can be attributed to the substitution of individual elements in the BFO-based *** and Eu substitutions contribute to the lattice distortion in a pseudo-cubic structure,while La is biased toward *** force microscopy confirmed that reversible switching of ferroelectric domains by nearly 180°can be realized through the prepared *** ferroelectric hysteresis loops showed that the order for the polarization contribution is as follows:Cu>Co>Mn(B-site),Sm>La>Eu(A-site).The current density voltage curves indicated that the order for leakage contribution is as follows:Mn

关键词： increasing entropy synergistic ferroelectric film remnant polarization leakage current

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An Encoding-Decoding Framework Based on CNN for circ RNA-RBP Binding Sites Prediction

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Chinese Journal of Electronics 2024年第1期33卷 256-263页

作者： Yajing GUO Xiujuan LEI Yi PAN School of Computer science Shaanxi Normal University faculty of Computer science and Control Engineering Shenzhen Institute of Advanced TechnologyChinese Academy of Sciences Department of Computer science Georgia State University

Predicting RNA binding protein(RBP) binding sites on circular RNAs(circ RNAs) is a fundamental step to understand their interaction mechanism. Numerous computational methods are developed to solve this problem, but they cannot fully learn the features. Therefore, we propose circ-CNNED, a convolutional neural network(CNN)-based encoding and decoding framework. We first adopt two encoding methods to obtain two original matrices. We preprocess them using CNN before fusion. To capture the feature dependencies, we utilize temporal convolutional network(TCN) and CNN to construct encoding and decoding blocks, respectively. Then we introduce global expectation pooling to learn latent information and enhance the robustness of circ-CNNED. We perform circ-CNNED across 37 datasets to evaluate its effect. The comparison and ablation experiments demonstrate that our method is superior. In addition, motif enrichment analysis on four datasets helps us to explore the reason for performance improvement of circ-CNNED.

关键词： Proteins RNA Neural networks Encoding Robustness Decoding Convolutional neural networks

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Electrodeposition of rare refractory metals in low-temperature ionic liquids

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Rare Metals 2024年第10期43卷 4921-4933页

作者： Lin-Lin Wang Han-Dong Jiao Rui Yuan Le-Yang Li Man-Peng Lin Rui-Yang Sun Jiu-San Xiao Shu-Qiang Jiao Institute of advanced Structure technology Beijing Institute of Technology State Key Laboratory of advanced Metallurgy University of Science and Technology Beijing

Rare refractory metals(RRMs) play a significant role in fundamental industries, including electronics,chemical industry, machinery, etc., and future advanced fields, such as aerospace and superconductivity. However,the traditional production processes of RRMs based on high-temperature thermal reduction cannot meet the requirements of low-energy consumption. This dilemma could be addressed efficiently by using a low-temperature electrodeposition strategy in ionic liquids(ILs). This review summarizes a panoramic view of the latest developments on the electrodeposition of RRMs in ILs after a brief review on the current industrial production methods of RRMs. Based on this, the electrochemical mechanism occurring at the cathode during the electrodeposition process of RRMs in different electrolytes and under different conditions is thoroughly discussed, because it is crucial for the successful production of pure RRMs. In addition, this review not only analyses the main challenges that hinder the industrial application of the electrodeposition of RRMs in ILs, but also proposes corresponding solutions. We hope this review can provide a valuable guidance for the fundamental research and industrial development of lowtemperature electrodeposition of RRMs.

关键词： Chemical industry

Pressure-induced hydrogen-dominant high-temperature superconductors

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National science Review 2024年第7期11卷 14-16页

作者： Ho-kwang Mao Shanghai advanced Research in Physical sciences Center for High Pressure science and technology advanced Research

Recent studies of hydrogen-dominant（superhydride） materials have led to putative discoveries of near-room temperature superconductivity at high pressures. The idea started more than half-a-century ago as a by-product of the quest for metallic hydrogen for which a natural consequence of its very high Debye temperature and phonon frequency due to the very low mass of the hydrogen atoms would lead to a high superconducting critical temperature （Tc） in weak coupling Bardeen-Cooper-Schrieffer（BCS） expression.

关键词： HYDRIDE LANTHANUM

Atomic-resolution Interfacial Microstructure and Thermo-electro-magnetic Energy Conversion Performance of Gd/Bi0.5Sb1.5Te3 Composites

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Energy & Environmental Materials 2024年第4期7卷 355-363页

作者： Chengshan Liu Wenjie Xu Ping Wei Shaoqiu Ke Wenjun Cui Longzhou Li Dong Liang Xianfeng Ye Tiantian Chen Xiaolei Nie Wanting Zhu Wenyu Zhao Qingjie Zhang State Key Laboratory of advanced technology for Materials Synthesis and Processing Wuhan University of Technology Foshan Xianhu Laboratory of the advanced Energy science and technology Guangdong Laboratory

Thermo-electro-magnetic materials with simultaneously large magnetocaloric(MC) and thermoelectric (TE) effects are the core part for designing TE/MC all-solid-state cooling *** MC phase with TE material is an effective ***,the elemental diffusion and chemical reaction occurring at the two-phase interfaces could significantly impair the cooling performance.

关键词： interfacial reaction magnetocaloric performance thermoelectric performance thermo-electro-magnetic materials

Green hydrothermal synthesis of multifunctional carbon dots from cassava pulps for metal sensing,antioxidant,and mercury detoxification in plants

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Carbon Resources Conversion 2024年第2期7卷 1-12页

作者： Teera Watcharamongkol Pacharaphon Khaopueak Chuleekorn Seesuea Kanokorn Wechakorn faculty of science and technology Kanchanaburi Rajabhat UniversityKanchanaburi 71190Thailand Department of Chemistry Faculty of Science and TechnologyRajamangala University of Technology ThanyaburiPathum Thani 12110Thailand advanced Photochemical and Electrochemical Materials Research Unit Faculty of Science and TechnologyRajamangala University of Technology ThanyaburiPathum Thani 12110Thailand

Carbon dots(CDs)have been attracted to nanocarbon materials for metal ion sensing,biological activity,and plant phytotoxicity due to their excellent photophysical properties,such as low cytotoxicity,high quantum yield,tunable fluorescence emission,and *** pulp,which consists mainly of starch,has been identified as a low-cost biomass waste from the cassava starch ***,this research developed CDs and nitrogen-doped CDs(NCDs)from cassava pulp using a one-step hydrothermal process in deionized water at 200℃.The effects of the synthesis conditions,including reaction time(6-24 h)and the nitrogen doping derivatives,were also *** and ethylenediamine doped-NCDs exhibited tunable fluorescence emission,strong quantum yield,high photostability,and tolerance to ***,the potential applications of CDs-12 h were demonstrated such as fluorescent sensors for metal ion sensing,antioxidant activity,and mercury detoxification in *** quenching of the CDs-12 h via both static and dynamic quenching mechanisms was observed in the presence of several metal ions such as Hg^(2+),Cu^(2+),and Fe^(3+)with the detection limit in micromolar levels and further applied to real water samples with good recovery and acceptable relative standard *** paper test strip coated with CDs-12 h could also detect these metal ions under UV *** and NCDs-EDA also showed potential DPPH radical scavenging activity and alleviated mercury toxicity in the Chinese cabbage seedlings with the incubation of CDs-12 h and NCDs-EDA-12 h(30 mg/L).

关键词： Carbon dot Nitrogen-doped carbon dot Cassava pulp Fluorescent sensor Antioxidant activity Mercury toxicity alleviation