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Journal of Advanced Ceramics 2024年第8期13卷 1143-1152页

作者： Jingwen Xi Linlin Liu Hongwei Qiao Jiacheng Luo xin Su xin Zhao Yugen xu Hao Chen Zhi Tan Jianguo Zhu Nuclear Power Institution of China Chengdu 610213China College of Materials Science and Engineering Sichuan UniversityChengdu 610064China

Enhancing the piezoelectricity of CaBi_(4)Ti_(4)O_(15)(CBT)ceramics is crucial for improving their application potential in high-temperature piezoelectric ***,we propose a strategy involving the introduction of larger Na/Bi ions at the A-site,effectively inhibiting the tilt of oxygen octahedra and flattening the potential energy *** flattening enhances the variation in polarization under external ***,substituting Nb/Mn at the B-site increases the deviation between positive and negative ionic centers,leading to stronger spontaneous polarization,while the induced defect dipoles restrict oxygen vacancy migration and increase the direct current resistivity(ρ_(dc)).The flattened potential energy profile and increased spontaneous polarization significantly enhance the overall performance of cBT ceramics,with the piezoelectric constant(d_(33))reaching 25 pC/N when the Curie temperature(Tc)=752℃.Piezoresponse force microscopy(PFM)and transmission electron microscopy(TEM)revealed submicron-long rectangular domains and nanoscale domains in the modified composition,indicating a high density of domain *** study presents an effective approach for enhancing the piezoelectric properties of bismuth layered-structured ferroelectrics(BLSFs),thereby improving the application potential of BLSFsathightemperatures.

关键词： piezoelectricity bismuth layered-structured ferroelectrics(BLSFs) potential energy profile spontaneous polarization high temperatures

Learning to Branch in Combinatorial Optimization With Graph Pointer Networks

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IEEE/CAA Journal of Automatica Sinica 2024年第1期11卷 157-169页

作者： Rui Wang Zhiming Zhou Kaiwen Li Tao Zhang Ling Wang xin xu Xiangke Liao IEEE the Xiangjiang Laboratory and the College of Systems Engineering National University of Defense TechnologyChangsha 410073China the Institute of Automation Chinese Academy of SciencesBeijing 100190China the College of Systems Engineering National University of Defense TechnologyChangsha 410073 the Hunan Key Laboratory of Multi-Energy System Intelligent Interconnection Technology Changsha 410073China the Department of Automation Tsinghua UniversityBeijing 100084China the College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China the College of Computer Science and Technology National University of Defense TechnologyChangsha 410073China

Traditional expert-designed branching rules in branch-and-bound(B&B) are static, often failing to adapt to diverse and evolving problem instances. Crafting these rules is labor-intensive, and may not scale well with complex *** the frequent need to solve varied combinatorial optimization problems, leveraging statistical learning to auto-tune B&B algorithms for specific problem classes becomes attractive. This paper proposes a graph pointer network model to learn the branch rules. Graph features, global features and historical features are designated to represent the solver state. The graph neural network processes graph features, while the pointer mechanism assimilates the global and historical features to finally determine the variable on which to branch. The model is trained to imitate the expert strong branching rule by a tailored top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. It also outperforms state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances.

关键词： Branch-and-bound(B&B) combinatorial optimization deep learning graph neural network imitation learning

Growth hormone improves insulin resistance in visceral adipose tissue after duodenal-jejunal bypass by regulating adiponectin secretion

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World Journal of Diabetes 2024年第6期15卷 1340-1352页

作者： Zi-Tian Liu guang-Wei Yang Xiang Zhao Shuo-Hui Dong Yang Jiao Zheng Ge Ao Yu Xi-Qiang Zhang xin-Zhen xu Zhi-Qiang Cheng Xiang Zhang Ke-xin Wang Department of General Surgery Qilu Hospital of Shandong UniversityJinan 250012Shandong ProvinceChina Department of General Surgery Shandong University of Qilu Hospital(Qingdao)Qingdao 266000Shandong ProvinceChina

BACKGROUND The mechanism of improvement of type 2 diabetes after duodenal-jejunal bypass(DJB)surgery is not *** To study the morphological and functional changes in adipose tissue after DJB and explore the potential mechanisms contributing to postoperative insulin sensitivity improvement of adipose tissue in a diabetic male rat *** DJB and sham surgery was performed in a-high-fat-diet/streptozotocin-induced diabetic rat *** adipose tissue was weighed and observed under *** inguinal fat to represent subcutaneous adipose tissue(SAT)and mesangial fat to represent visceral adipose ***-sequencing was utilized to evaluate gene expression alterations *** hematoxylin and eosin staining,reverse transcription-quantitative polymerase chain reaction,western blot,and enzyme-linked immunosorbent assay were used to study the *** resistance was evaluated by *** After DJB,whole body blood glucose metabolism and insulin sensitivity in adipose tissue *** cell volume in both visceral adipose tissue(VAT)and SAT *** to SAT,VAT showed more significantly functional alterations after DJB and KEGG analysis indicated growth hormone(GH)pathway and downstream adiponectin secretion were involved in metabolic *** circulating GH and adiponectin levels and GH receptor and adiponectin levels in VAT *** experiment showed that GH stimulated adiponectin secretion and improve insulin *** GH improves insulin resistance in VAT in male diabetic rats after receiving DJB,possibly by increasing adiponectin secretion.

关键词： Growth hormone Insulin resistance Bariatric surgery Adipose tissue Adiponectin

An Integral Method for Solving Dynamic Equations with Fluid–Solid Coupling

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Acta Mechanica Solida Sinica 2024年第1期37卷 99-108页

作者： xin Zhang Jie Liu Pu xue Shuowen Yan Yahao xu M.S.Zahran School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Department of Civil Engineering Military Technical CollegeCairo 11435Egypt

In this work,a new methodology is presented to mainly solve the fluid–solid interaction(FSI)*** methodology combines the advantages of the Newmark precise integral method(NPIM)and the dual neural network(DNN)*** NPIM is employed to modify the exponential matrix and loading vector based on the DNN integral *** involves incorporating the basic assumption of the Newmark-βmethod into the dynamic equation and eliminating the acceleration term from the dynamic equilibrium *** a result,the equation is reduced to a first-order linear equation ***,the PIM is applied to integrate the system step by step within the *** DNN method is adopted to solve the inhomogeneous term through fitting the integrand and the original function with a pair of neural networks,and the integral term is solved using the Newton–Leibniz *** examples demonstrate that the proposed methodology significantly improves computing efficiency and provides sufficient precision compared to the DNN *** is particularly evident when analyzing large-scale structures under blast loading conditions.

关键词： Newmark precise integral method(NPIM) Dual neural networks(DNN) Fluid-solid interaction(FSI) Dynamic time-history analysis Blast loading

Photoinduced copper-catalyzed alkoxyl radical-triggered ring-expansion/aminocarbonylation cascade

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Chinese Chemical Letters 2024年第6期35卷 331-336页

作者： Jing-Qi Tao Shuai Liu Tian-Yu Zhang Hong xin xu Yang xin-Hua Duan Li-Na Guo Department of Chemistry School of ChemistryXi’an Key Laboratory of Sustainable Energy Material Chemistry and Engineering Research Center of Energy Storage Materials and DevicesMinistry of EducationXi’an Jiaotong UniversityXi’an 710049China School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China

A photoinduced copper-catalyzed alkoxyl triggered C-C bond cleavage/aminocarbonylation cascade is *** adjusting the structure of alkoxyl radical precursors,functionalized lactones and ketoamides were synthesized with good yields and excellent functional group tolerance under redox-neutral ***,this protocol enables the integration of lactone fragments with many amine drugs and drug fragments.

关键词： Copper catalysis Ring-expansion Aminocarbonylatioin Macrolactones Keto-amides

Water modeling on fluid flow and mixing phenomena in a BOF steelmaking converter

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Journal of Iron and Steel Research International 2024年第3期31卷 595-607页

作者： xin-yu Cai Hao-jian Duan Ding-han Li Anjun xu Li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

A 1∶8 physical water model was constructed to investigate the fluid flow and mixing phenomena in the basic oxygen furnace(BOF)*** particle image velocimetry was employed to measure the velocity distribution of the bath and the high-speed camera was applied to capture the cavity shape in the combined blowing BOF *** mixing time for varied operating conditions was measured by the stimulus-response *** cavity depth increased with the decrease in the lance height and the increase in the top gas flow rate while the bottom blowing gas had little influence on the cavity *** minimum cavity depth was obtained under the condition of a 69.8 m^(3)/h top gas flow rate,a 287.5 mm lance height and a 0.93 m^(3)/h bottom blowing gas flow rate,which was 161.2 *** mixing time decreased as the lance height decreased and the top blowing gas flow rate *** mixing time was first decreased and then increased with the increase in the bottom gas flow *** the condition of 69.8 m^(3)/h gas flow rate of top blowing,the 287.5 mm lance height and the 0.93 m^(3)/h gas flow rate of bottom blowing,the mixing time in the converter was 48.65 *** empirical formula between the stirring power and the mixing time in the converter was calculated.

关键词： Water model Fluid flow Particle image velocimetry Mixing time BOF converter

Paradigm for Determining the Optimal Ultradeep and Superthick Saline Aquifer for High-TDS Mine Water Geological Storage

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Acta Geologica Sinica(English Edition) 2024年第3期98卷 771-785页

作者： LI xin CHEN Ge xu Zhimin LIU Qi CHEN Tianci SUN Yajun School of Resources and Geosciences China University of Mining and TechnologyXuzhouJiangsu 221116China National Professional Central Laboratory of Basic Research on Mine Water Disaster Prevention and Control Technology XuzhouJiangsu 221116China

Saline aquifers are the most popular waste and CO_(2)injection and storage reservoirs *** project proposes that several optimal injection positions should be investigated as hydraulic pressure-focused positions,in order to relieve the high demands of pump *** comprehensive indices(F_(i))representing the injectivity of different burial depths were obtained by using information entropy,based on the mercury injection experimental data of 13 rock *** results demonstrated that the burial depths of No.4,No.1 and No.2 in the Liujiagou Formation were the most suitable positions for hydraulic focused injection,which means the upper 30 m thickness could be regarded as the hydraulic focused range in the saline aquifer with an average thickness of 400 *** addition,some laboratory experiments and in situ tests were carried out for the purpose of certifying and analyzing results,including SEM,XRD,brittleness index and *** results suggested that the rock samples at the No.4,No.1 and No.2 burial depth ranges have loose microstructure,weak cementation,as well as dual pores and *** lithology is mainly quartz and feldspar,but the clay mineral content is high(10%-25%),which is positive for *** lithology is suitable for hydraulic fracturing to form extended cracks and micro-fissures during high-TDS(total dissolved solids)mine water injection,because of the high brittleness ***,a theoretical and technical framework for high-TDS mine water injection was established,based on operating pilot *** theoretical defects and drawbacks learned from the field practices were summarized and solutions *** research in this study could provide guidance and a paradigm for the inexpensive treatment of high-TDS mine water by injection and storage.

关键词： ultradeep Liujiagou Formation high-TDS mine water optimal hydraulic injection positions information entropy reservoir spatial characteristics

Side ionic-gated perovskite/graphene heterojunction synaptic transistor with bipolar photoresponse for neuromorphic computing

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Photonics Research 2024年第6期12卷 1167-1174页

作者： XIAOYING HE MINGHAO xu SHILIN LIU KUN WANG BOWEN CAO LAN RAO XIANGJUN xin School of Electronic Engineering and Beijing Key Laboratory of Space-Ground Interconnection and Convergence Beijing University of Posts and TelecommunicationsBeijing 100876China Key Laboratory of Semiconductor Materials Science Beijing Key Laboratory of Low Dimensional Semiconductor Materials and DevicesInstitute of SemiconductorsChinese Academy of SciencesBeijing 100083China

By combining the good charge transport property of graphene and the excellent photo-carrier generation char-acteristic of perovskite nanocrystal,we propose and demonstrate an ionic-gated synaptic transistor based on CsPbBr_(3)∕graphene heterojunction for bipolar *** the potential barrier of the CsPbBr_(3)∕graphene heterojunction by the ionic-gate of the electrical double-layer effect can promote the sepa-ration of photogenerated carriers and effectively retard their *** the ionic-gate-tunable Fermi level of graphene and the pinning effect of perovskite nanocrystal,the bipolar photocurrent responses correspond-ing to the excitatory and inhibitory short-term and long-term plasticity are realized by adjusting the negative gate bias.A series of synaptic functions including logic operation,Morse coding,the optical memory and electrical erasure effect,and light-assisted re-learning have also been demonstrated in an optoelectronic collaborative ***,the excellent optical synaptic behaviors also contribute to the handwritten font recognition accuracy of-95%in artificial neural network *** results pave the way for the fabrication of bipolar photoelectric synaptic transistors and bolster new directions in the development of future integrated human ret-inotopic vision neuromorphic systems.

关键词： perovskite ionic Morse

Searching for plant NLR immune receptors conferring resistance to potyviruses

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The Crop Journal 2024年第1期12卷 28-44页

作者： xin Hong Shufen Li Xiaofei Cheng Haijian Zhi Jinlong Yin Kai xu Jiangsu Key Laboratory for Microbes and Functional Genomics Jiangsu Engineering and Technology Research Center for MicrobiologyCollege of Life SciencesNanjing Normal UniversityNanjing 210023JiangsuChina College of Plant Protection Northeast Agricultural UniversityHarbin 150030HeilongjiangChina National Center for Soybean Improvement National Key Laboratory for Crop Genetics and Germplasm EnhancementKey Laboratory of Biology and Genetic Improvement of Soybean-Ministry of AgricultureNanjing Agricultural UniversityNanjing 210095JiangsuChina

To fight against invasion by pathogens,plants have evolved an elaborate innate immune system,of which the nucleotide-binding domain leucine-rich repeat-containing receptor(NLR)acts as the sensor and immune ***,comprising one of the largest genera of plant viruses,cause severe crop yield losses *** crop resistance to potyviruses can be used in breeding and plant transgenesis to control disease *** review summarizes achievements in mapping and cloning NLR genes conferring dominant resistance against potyvirus in the families Fabaceae,Solanaceae,Brassicaceae,and *** compares mechanisms of potyviral protein recognition and downstream signaling employed by NLRs and discusses strategies for exploiting NLRs to better control diseases caused by potyviruses.

关键词： NLR Potyvirus resistance Genetic diversity Mapping Engineer

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： xu Pan Wei Jiang Chuan Yue Shi-Jun Lei Yu-xin Cui Qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation