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Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： S.W.Wi y.S.Lee Department of Physics and Integrative Institute of Basic Sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum.y.eld originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence Sensitizer Rare earths

Efficient hydrogenolysis of fructose to 1,2-propanediol over bifunctional Ru-WO_(x)-mgO_(y) catalysts under mild reaction conditions via enhancing the chemoselective cleavage of C-C bonds

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Journal of Energy Chemistry 2024年第5期92卷 311-321页

作者： Shuang Luo Tie Shu min mao Haijie yu yuxin Zheng Daqian Ding Lingmei liu Kexin yao Jianjian Wang School of Chemistry and Chemical Engineering State Key Laboratory of Coal Mine Disaster Dynamics and ControlInstitute of Advanced Interdisciplinary StudiesMulti-scale Porous Materials CenterChongqing UniversityChongqing 401331China Key Laboratory for Efficient Conversion and Circular Economy of Coal Chemical Engineering CollegeInner Mongolia University of TechnologyHohhot 010051Inner MongoliaChina

Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low efficiency and harsh reaction ***,we have successfully synthesized a novel bifunctional Ru-WO_(x)-mgO_(y) catalyst through a facile'one-pot'solvothermal ***,this catalyst exhibits exceptional catalytic performances in the conversion of fructose to 1,2-PDO under mild reaction *** yield of 1,2-PDO is up to 56.2%at 140°C for 4 h under an ultra-low hydrogen pressure of only 0.2 mPa,surpassing the reported results in recent literature(below 51%).Comprehensive characterizations and density functional theory(DFT)calculations reveal that the presence of oxygen vacancies in the Ru-WO_(x)-mgO_(y) catalyst,serving as active acidic sites,facilitates the chemoselective cleavage of C-C bonds in fructose,which leads to the generation of active intermediates and ultimately resulted in the high yield of 1,2-PDO.

关键词： Biomass Fructose 1,2-Propanediol Retroaldol condensation Heterogenous catalysis

On the Probability of Generating a Primitive matrix

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Journal of Systems Science & Complexity 2024年第4期37卷 1755-1771页

作者： CHEN Jingwei FENG yong liu yang WU Wenyuan Chongqing Key Laboratory of Automated Reasoning and Cognition Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Chongqing College University of Chinese Academy of SciencesChongqing 400714China Key Laboratory of Advanced manufacturing Technology of ministry of Education Guizhou UniversityyGuiyang 550025China Information Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China

Given a k×n integer primitive matrix A(i.e.,a matrix can be extended to an n×n unimodular matrix over the integers)with the maximal absolute value of entries‖A‖bounded by an integer λ from above,the authors study the probability that the m×n matrix extended from A by appending other m-k row vectors of dimension n with entries chosen random.y.and independently from the uniform distribution over{0,1,…,λ-1}is still *** authors present a complete and rigorous proof of a lower bound on the probability,which is at least a constant for fixed m in the range[k+1,n-4].As an application,the authors prove that there exists a fast Las Vegas algorithm that completes a k×n primitive matrix A to an n×n unimodular matrix within expected O(n^(ω)log‖A‖)bit operations,where O is big-O but without log factors,ω is the exponent on the arithmetic operations of matrix multiplication.

关键词： Integer matrix matrix completion probabilistic algorithm unimodular matrix

Review on synergistic damage effect of irradiation and corrosion on reactor structural alloys

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Nuclear Science and Techniques 2024年第3期35卷 109-141页

作者： Hui liu Guan-Hong Lei He-Fei Huang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research *** paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt *** competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this *** approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.

关键词： Irradiation and corrosion Synergistic effect Austenitic stainless steels Nickel-based alloys Reactors

High-efficiency crystalline white organic lightemitting diodes

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Light(Science & Applications) 2024年第4期13卷 747-759页

作者： yijun liu Feng Zhu yue Wang Donghang yan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China. School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China. State Key Laboratory of Supramolecular Structure and materials Jilin UniversityChangchun 130012China

Crystalline white organic light-emitting diodes(C-WOLEDs)are promising candidates for lighting and display *** is urgently necessary,however,to develop energy-saving and high-efficiency C-WOLEDs that have stable and powerful emission to meet commercial ***,we report a crystalline host matrix(CHm)with embedded nanoaggregates(NA)structure for developing high-performance C-WOLEDs by employing a thermally activated delayed fluorescence(TADF)material and orange phosphorescent dopants(Phos.-D).The CHm-TADFNA-D WOLED exhibit a remarkable EQE of 12.8%,which is the highest performance WOLEDs based on crystalline *** device has a quick formation of excitons and a well-designed energy transfer process,and possesses a fast ramping of luminance and current *** to recently reported high-performance WOLEDs based on amorphous material route,the C-WOLED achieves a low series-resistance Joule-heat loss ratio and an enhanced photon output,demonstrating its significant potential in developing the next-generation WOLEDs.

关键词： diodes dopant crystalline

Interaction of yttrium barrier and calcium-rich phase on production and properties of WC precursor powders and alloys

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Journal of Rare Earths 2024年第1期42卷 228-236,I0008页

作者： Wen He Dunqiang Tan Zhiqiang yi Zhiqiang liu School of materials Science and Engineering Nanchang UniversityNanchang330031China Instrumental Analysis Center of Nanchang Hangkong University Nanchang330063China

In order to reduce or eliminate the adverse effects of calcium impurity,the interaction of Ca and rare earth y co-doping on the preparation of WC-Co cemented carbides was investigated.X-ray diffraction,scanning electron microscopy and transmission electron microscopy were employed to analyze the phase compositions,particle sizes and morphologies of them,*** results show that the second type of"yttrium barrier effect"is observed and the adverse influence of Ca-rich phase on tungsten powder can be eliminated by *** flexural strength and fracture toughness of yG6-0.01%Ca+0.09%y alloy are 2199.5 mPa and 11.49 mPa·m^(1/2),showing improvement of 6.5% and 2.7% compared to yG6 alloy,*** evolutions of Ca-rich phase and y-rich phase at the every alloy preparation stage of WO_(3),W,WC and cemented carbides are ***,the strengthening mechanism of WC-Co cemented carbide with co-addition of Ca and y is proposed.

关键词： yttrium barrier effect Ca-rich phase WC-Co cemented Carbide microstructures mechanisms Rare earths

A new insight into LPSO phase transformation and mechanical properties uniformity of large-scale mg-Gd-y-Zn-Zr alloy prepared by multi-pass friction stir processing

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Journal of magnesium and Alloys 2024年第5期12卷 2041-2056页

作者： Xiaohu Guan Wen Wang Ting Zhang Pai Peng Qiang liu Peng Han Ke Qiao Jun Cai Liqiang Wang Kuaishe Wang School of metallurgical Engineering National and Local Joint Engineering Research Center for Functional Materials ProcessingXi’an University of Architecture and TechnologyNo.13 Yanta RoadXi’anShaanxi 710055China Xi’an Rare metal materials Institute Co.Ltd Xi’an 710016China State Key Laboratory of metal matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghai 200240China

A large-scale fine-grained mg-Gd-y-Zn-Zr alloy plate with high strength and ductility was successfully prepared by multi-pass friction stir processing(mFSP)technology in this *** structure of grains and long period stacking ordered(LPSO)phase were characterized,and the mechanical properties uniformity was ***,a quantitative relationship between the microstructure and tensile yield strength was *** results showed that the grains in the processed zone(PZ)and interfacial zone(IZ)were refined from 50μm to 3μm and 4μm,respectively,and numerous original LPSO phases were *** IZ,some block-shaped 18R LPSO phases were transformed into needle-like 14H LPSO phases due to stacking faults and the short-range diffusion of solute *** severe shear deformation in the form of kinetic energy caused profuse stacking fault to be generated and move rapidly,greatly increasing the transformation rate of LPSO *** mFSP,the ultimate tensile strength,yield strength and elongation to failure of the large-scale plate were 367 mPa,305 mPa and 18.0% *** refinement and LPSO phase strengthening were the major strengthening mechanisms for the mFSP *** particularly,the strength of IZ was comparable to that of PZ because the strength contribution of the 14H LPSO phase offsets the lack of grain refinement strengthening in *** result opposes the widely accepted notion that IZ is a weak region in mFSP-prepared large-scale fine-grained plate.

关键词： Friction stir processing multi-pass mg-Gd-y-Zn-Zr alloy LPSO phase transformation mechanical properties

Innovative mn3-xO4-y@NCA design:Leveraging mn/O vacancies and amorphous architecture for enhanced sodium-ion storage

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Journal of Energy Chemistry 2024年第10期97卷 747-756页

作者： Kaijun Xie Xin liu Kai Xia Lipeng Diao Ping Lu mengmeng Wang Long Fang yihui Zou Dongjiang yang Xiaodong Zhang College of Chemistry and Chemical Engineering College of Environmental Science and Engineering State Key Laboratory of Bio-fibers and Eco-textiles Shandong Collaborative Innovation Center of Marine Biobased Fibers and Ecological Textiles Institute of Marine Biobased Materials Qingdao University Institute of micro/Nano materials and Devices Ningbo University of Technology

manganese-based oxide electrode materials suffer from severe Jahn-Teller（J-T） distortion,leading to severe cycle instability in sodium ion ***,it is difficult to adjust the electron at d orbitals exactly to a low spin state to eliminate orbital degeneracy and suppress J-T distortion *** article constructed concentration-controllable mn/O coupled vacancy and amorphous network in mn3O4and coated it with nitrogen-doped carbon aerogel(mn3-xO4-y@NCA).The existence of mn/O vacancies has been confirmed by scanning transmission electron microscopy（STEm） and positron annihilation lifetime spectroscopy（PALS）.Atomic absorption spectroscopy（AAS） and X-ray photoelectron spectroscopy（XPS） determine the most optimal ratio of mn/O vacancies for sodium ion storage is 1:*** functional theory（DFT） calculations prove that mn/O coupled vacancies with the ratio of 1:2could exactly induce a low spin states and a d4electron configuration of mn,suppressing the J-T distortion *** abundant amorphous regions can shorten the transport distance of sodium ions,increase the electrochemically active sites and improve the pseudocapacitance *** the synergetic effect of mn/O coupled vacancies and amorphous regions,mn3-xO4-y@NCA exhibits an energy density of 37.5 W h kg-1and an ultra-high power density of 563 W kg-1in an asymmetric *** sodium-ion batteries,it demonstrates high reversible capacity and exceptional cycling *** research presents a new method to improve the Na+storage performance in manganese-based oxide,which is expected to be generalized to other structural distortion.

关键词： Amorphous network Concentration-controllable mn/O coupled vacancies manganese-based metal oxide Sodium ion battery Sodium ion supercapacitor

Guided-yNet: Saliency Feature-Guided Interactive Feature Enhancement Lung Tumor Segmentation Network

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Computers, materials and Continua 2024年第3期80卷 4813-4832页

作者： Zhou T. Pan y. Lu H. Dang P. Guo y. Wang y. School of Computer Science and Engineering North Minzu University Yinchuan 750021 China Key Laboratory of Image and Graphics Intelligent Processing of State Ethnic Affairs Commission North Minzu University Yinchuan 750021 China School of medical Information & Engineering Ningxia Medical University Yinchuan 750004 China

multimodal lung tumor medical images can provide anatomical and functional information for the same lesion. Such as Positron Emission Computed Tomography (PET), Computed Tomography (CT), and PET-CT. How to utilize the lesion anatomical and functional information effectively and improve the network segmentation performance are key questions. To solve the problem, the Saliency Feature-Guided Interactive Feature Enhancement Lung Tumor Segmentation Network (Guide-yNet) is proposed in this paper. Firstly, a double-encoder single-decoder U-Net is used as the backbone in this model, a single-coder single-decoder U-Net is used to generate the saliency guided feature using PET image and transmit it into the skip connection of the backbone, and the high sensitivity of PET images to tumors is used to guide the network to accurately locate lesions. Secondly, a Cross Scale Feature Enhancement module (CSFEm) is designed to extract multi-scale fusion features after downsampling. Thirdly, a Cross-Layer Interactive Feature Enhancement module (CIFEm) is designed in the encoder to enhance the spatial position information and semantic information. Finally, a Cross-Dimension Cross-Layer Feature Enhancement module (CCFEm) is proposed in the decoder, which effectively extracts multimodal image features through global attention and multi-dimension local attention. The proposed method is verified on the lung multimodal medical image datasets, and the results show that the mean Intersection over Union (mIoU), Accuracy (Acc), Dice Similarity Coefficient (Dice), Volumetric overlap error (Voe), Relative volume difference (Rvd) of the proposed method on lung lesion segmentation are 87.27%, 93.08%, 97.77%, 95.92%, 89.28%, and 88.68%, respectively. It is of great significance for computer-aided diagnosis. Copyright © 2024 The Authors. Published by Tech Science Press.

关键词： cross-dimension feature enhancement cross-modal feature enhancement medical image segmentation saliency feature guidance U-Net