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Acta Metallurgica Sinica(English Letters) 2016年第2期29卷 120-128页

作者： Sheng Li yu-Zeng Chen yu-ke cao Feng Liu State key Laboratory of Solidification Processing Northwestern Polytechnical University

It is well known that, in kinetics, the interaction between dislocations and interstitial solute normally exerts strong solute drag effect on dislocations, leading to strong solution hardening of the metals. However, due to the low mobility of interstitial solute in many metals, thermodynamic aspect of the interaction between dislocations and interstitial solute is often unobservable and omitted. It will be shown in this article by reviewing the H-induced behaviors in metal-H systems, especially the recent progress in Pd-H system that, when the interstitial solute atoms are highly mobile and able to collect in the vicinity of mobile dislocations easily, the scenario will be remarkably different. The interaction between dislocations and these highly mobile interstitial solute atoms, in thermodynamics, will reduce the line energy of dislo- cations and will facilitate the generation of dislocations, leading to an increase in dislocation density and an enhanced strain hardening of metals upon plastic deformation.

关键词： Plastic deformation Dislocation Interstitial solute Strengthening mechanism Thermodynamics

Experimental Observing Damage Evolution in Cement Pastes Exposed to External Sulfate Attack by in situ X-ray Computed Tomography

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 164-170页

作者： WU Min cao Kailei XIAO Weirong yu Zetai cao Jierong DING Qingjun LI Jinhui China Railway Construction Corporation Harbour and Channel Engineering Bureau Group Co. LTDZhuhai 519000China Con-struction Headquarters of Zhoushan Liuheng Bridge Phase II Project Zhoushan 316000China China Railway Construction Bridge En-gineering Bureau Group Co. LTDTianjin 300000China State key Laboratory of Silicate Material for Architecture(Wuhan University of Technology) Wuhan 430070China College of Materials Science and Engineering Wuhan Textile UniversityWuhan 430200China

The paper presents experimental investigation results of crack pattern change in cement pastes caused by external sulfate attack(ESA).To visualize the formation and development of cracks in cement pastes under ESA,an X-ray computed tomography(X-ray CT)was used,i e,the tomography system of Zeiss Xradia 510 *** results indicate that X-CT can monitor the development process and distribution characteristics of the internal cracks of cement pastes under ESA with attack *** addition,the C3A content in the cement significantly affects the damage mode of cement paste specimens during sulfate *** damage of ordinary Portland cement(OPC)pastes subjected to sulfate attack with high C3A content are severe,while the damage of sulfate resistant Portland cement(SRPC)pastes is much smaller than that of OPC ***,a quadratic function describes the correlation between the crack volume fraction and development depth for two cement pastes immermed in sulfate solution.

关键词： concrete external sulfate attack damage evolution situ X-ray computed tomography

Hypoxia reoxygenation induces premature senescence in neonatal SD rat cardiomyocytes

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Acta Pharmacologica Sinica 2007年第1期28卷 44-51页

作者： Feng-xiang ZHANG~2 Ming-long CHEN~2 Qi-jun SHAN Jian-gang ZOU Chun CHEN Bing YANG Dong-jie XU yu JIN ke-jiang cao~3 Department of Cardiology,First Affiliated Hospital of Nanjing Medical University,Nanjing 210029,China Department of Cardiology First Affiliated Hospital of Nanjing Medical University Nanjing China

Aim:To investigate whether hypoxia reoxygenation induces premature senes-cence in neonatal Sprague-Dawley(SD)rat ***:Cardio-myocytes were isolated from neonatal SD rat heart and identified by *** control cultures were incubated at 37℃ in a humidified atmo-sphere of 5% CO2and 95% *** hypoxic cultures were incubated in a modularincubator chamber filled with 1% O2,5% CO2,and balance N2for 6 *** reoxygen-ated cultures were subjected to 1% O2and 5% CO2 for 6 h,then 21% oxygen for 4,8,12,24,and 48 h,*** proliferation was determined using bromo-deoxyuridine *** ultrastructure of cardiomyocytes was observed byusing an electron microscope.β-Galactosidase activity was determined by usinga senescence β-galactosidase Staining Kit.p16INK4aand telomerase reverse tran-scriptase(TERT)mRNA levels were measured by real time quantitative *** expression was determined by *** activi-ties were assayed by using the Telo TAGGG Telomerase PCR ELISA(plus)***:The initial cultures consisted of pure cardiomyocytes identified by *** proportion of BrdU positive cells was reduced significantly in thehypoxia reoxygenation-treated group(P<0.01).Under the condition of hypoxiareoxygenation,mitochondrial dehydration appeared;p16INK4aand TERT mRNAlevels,β-galactosidase activity,TERT protein expression and telomerase activi-ties were all significantly increased(P<0.01 or P<0.05).Conclusion:These dataindicate that premature senescence could be induced in neonatal SD rat cardiomyo-cytes exposed to hypoxia *** TERT significantly increased,it could not block senescence.

关键词： cardiomyocytes hypoxia reoxygenation p16INK4a telomerase reverse transcriptase β-galactosidase

Mitrification－Denitrification Lossof Added Nitrogenin Flooded Rice Rhizosphere

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Pedosphere 1994年第2期4卷 145-152页

作者： LI XIN-HUI ZHU ZHAO-LIANG CAI GUI-XIN ZHOU ke-yu and cao YA-CHENG(Institute of Soil Science, Academia Sinica, P.O .Box 821 . Nanjing (China))

Nitrification-denitrification losses of ￣15N-labelled nitrate and ammonium applied to the rhizosphere andnonrhizosphere of flooded rice were evaluated in 2 greenhouse rhizobox experiments. The loss of added Nvia denitrification was estimated directly by measuring the total fluxes of (N_2O+N_2)￣15N. It was found that 67% and51%-56% of ￣15N-nitrate added to rice rhizosphere were lost as (N_2O+N_)-￣15N in the 2 experiments, respectively,which were comparable to that added to nonrhizosphere soil (70%and47%, respectively), implying that tbedenitrifying activity in rice rhizosphere was as high as that in nonrhizosphere soil. However, only trace amounts(0-0.3% of added N) were recovered as (N_2O+N_2)-￣15N when ￣15N-ammonium was applied to either rhizosphere ornonrhizosphere, which seems to indicate that the nitrifying activity in the either rhizosphere or nonrhizosphere soilswas quite low. The apparent denitrification calculated from ￣15N balance studies was 10%-47% higher than the totalflux of (N_2O+N_2)-￣15N. Reasons for the large differences can not be explained satisfactorily. Though the denitrifyingactivity in rhizospbere was high and comparable to that in nonrhizosphere soil, presumably due to the low nitrifyingactivity and/ or the strong competition of N uptake against denitrification, the nitrification-denitrification takingplace in rhizosphere could not be an important mechanism of loss of ammonium N in flooded rice-soil system.

关键词： denitrification ￣15N balance nitrification rhizobox rhizosphere

MXene Hybridized Polymer with Enhanced Electromagnetic Energy Harvest for Sensitized Microwave Actuation and Self‑Powered Motion Sensing

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Nano-Micro Letters 2025年第3期17卷 265-279页

作者： yu‑Ze Wang yu‑Chang Wang Ting‑Ting Liu Quan‑Liang Zhao Chen‑Sha Li Mao‑Sheng cao School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081People’s Republic of China School of Materials Science and Engineering Peking UniversityBeijing 100871People’s Republic of China School of Mechanical and Material Engineering North China University of TechnologyBeijing 100144People’s Republic of China key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of ChinaHeilongjiang UniversityHarbin 150080People’s Republic of China

Polymeric microwave actuators combining tissue-like softness with programmablemicrowave-responsive deformation hold great promise for mobile intelligentdevices and bionic soft robots. However, their application is challenged by restricted electromagneticsensitivity and intricate sensing coupling. In this study, a sensitized polymericmicrowave actuator is fabricated by hybridizing a liquid crystal polymer with Ti3C2Tx(MXene). Compared to the initial counterpart, the hybrid polymer exhibits unique spacechargepolarization and interfacial polarization, resulting in significant improvements of230% in the dielectric loss factor and 830% in the apparent efficiency of electromagneticenergy harvest. The sensitized microwave actuation demonstrates as the shortenedresponse time of nearly 10 s, which is merely 13% of that for the initial shape memory polymer. Moreover, the ultra-low content of MXene (upto 0.15 wt%) benefits for maintaining the actuation potential of the hybrid polymer. An innovative self-powered sensing prototype that combinesdriving and piezoelectric polymers is developed, which generates real-time electric potential feedback (open-circuit potential of ~ 3 mV) duringactuation. The polarization-dominant energy conversion mechanism observed in the MXene-polymer hybrid structure furnishes a new approachfor developing efficient electromagnetic dissipative structures and shows potential for advancing polymeric electromagnetic intelligent devices.

关键词： Microwave absorption Electromagnetic response Energy harvest Self-sensing Soft actuator

Federated local causal structure learning

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Science China(Information Sciences) 2025年

作者： Kui yu Chen RONG Hao WANG Fuyuan cao Jiye LIANG School of Computer and Information Hefei University of Technology School of Computer and Information Technology Shanxi University

Local causal structure learning (LCS) efficiently identifies a set of direct neighbors of a specified variable from observational data. Additionally, it distinguishes direct causes and direct effects of this variable without learning the entire causal structure. While many LCS algorithms have been proposed, they do not consider the data privacy-preserving problem,which has attracted extensive attention from academia and industry. To address this issue, we propose a federated local causal structure learning (FedLCS) algorithm to learn local causal structures in privacy-preserving data in a federated ***, FedLCS introduces a layer-wise federated local skeleton learning algorithm to construct the local skeleton. Based on this skeleton, it introduces a federated local skeleton orientation algorithm and an extension-and-backtracking orientation algorithm to orient the edges. Finally, FedLCS uses a federated local extension-and-backtracking orientation algorithm to orient the remaining edges. Extensive experiments on benchmark, synthetic, and real datasets demonstrate that FedLCS can learn the local causal structure of a given variable in a federated setting.

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可燃蒸汽爆炸极限装置及工业应用的研究

现代化工 2017年第1期37卷 160-163,165页

作者：秦宝刚袁向前宋宏宇曹可华东理工大学化学工程联合国家重点实验室上海200237

为了研究甲醇蒸气在氧气中的爆炸特性,研发一套爆炸实验装置。装置采用注射器直接注入可燃液体的配气方式,加热套加热的方式,根据定容爆炸机理,采用爆破片爆破作为判据。结果表明,甲醇爆炸极限实验值和文献数据对比绝对偏差为0.5%(体积... 详细信息

为了研究甲醇蒸气在氧气中的爆炸特性,研发一套爆炸实验装置。装置采用注射器直接注入可燃液体的配气方式,加热套加热的方式,根据定容爆炸机理,采用爆破片爆破作为判据。结果表明,甲醇爆炸极限实验值和文献数据对比绝对偏差为0.5%(体积分数),表明装置的可靠性。最大含氧量与爆炸极限是相互对应的。随着温度、压力升高,最大含氧量变低。利用NRTL方程,得到质量分数85%甲醇水溶液的温度和饱和蒸气压的曲线。结合爆炸极限实验压力与温度曲线,得到安全操作区,为工业应用提供安全操作范围和理论依据。

关键词：甲醇氧气最大含氧量爆炸极限工业应用

Aperiodically semi-intermittent-based fixed-time stabilization and synchronization of delayed discontinuous inertial neural networks

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Science China(Information Sciences) 2025年第1期68卷 238-254页

作者： Guodong ZHANG Jinde cao School of Mathematics and Statistics South-Central Minzu University School of Mathematics Southeast University

This article concentrates on the fixed-time stabilization(FS) and fixed-time synchronization(FTS) of discontinuous inertial neural networks(DINNs) with distributed delays. Using mathematical induction to a new differential equality, a novel fixed-time stability lemma is constructed. Then, by designing an aperiodically semi-intermittent switching control and combining it with the theory of nonsmooth analysis, some novel criteria on the FS and FTS of DINNs are obtained. Unlike the methods used in most existing studies, the FS and FTS results are structured using the newly proposed fixed-time stability lemma and the nonreduced-order approach, resulting in broader practical applications and strengthening the scientific quality of the derived results. Lastly, numerical simulations and applications proffer the effectiveness of the established FS and FTS criteria.

关键词： inertial neural networks fixed-time synchronization semi-intermittent switching control nonreduced-order approach fixed-time stabilization

Systematic Acupuncture Explains Acupuncture at Baihui(GV20) and Fengchi(GB20) Targeting the Inflammatory Response to Regulate Migraine

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Journal of Traditional Chinese Medicine 2025年

作者： MIN yu ZHENG Meifeng SUN Ju PENG Zetong cao Zhixian HUANG Xiaohua Medical College of Acu-Moxi and Rehabilitation， Guangzhou University of Chinese Medicine Department of Rehabilitation Medicine， the Affiliated Panyu Central Hospital of Guangzhou Medical University

Objective: To take Baihui (GV20) and Fengchi (GB20) targeting inflammatory response to regulate migraine as an example to describe a new method for studying the mechanism of stimulating ***: The target information of Baihui (GV20) and Fengchi (GB20) was retrieved， and after intersection with migraine， Kyoto Encyclopedia of Genes and Genomes (keGG)， Reactome， and UniProt keywords were used for functional enrichment. After selecting the main pathway， rats were selected and nitroglycerin was used for modeling， and the behavioral scores， inflammatory factors， heme oxygenase 1 (HMOX1)， protein kinase B (AKT1)， signal transducer and activator of transcription 3 (STAT3)， phosphorylated extracellular signal-regulated kinase 1/2 (P-ERK1/ERK2) and other states of the rats in the acupuncture， twisting， and electroacupuncture groups were ***: A total of 135 Baihui (GV20) targets and 27 Fengchi (GB20) targets were collected. A total of 73 target information were obtained after the intersection of these targets in migraine. These 73 targets have three main pathways: hypoxia-inducible factor 1 (HIF-1) signaling pathway， signaling by interleukins and inflammatory response. The main targets in the pathway were verified and found that interleukin-1 beta (IL-1β)， interleukin-6 (IL-6)， tumor necrosis factor-alpha (TNF-α) and HMOX1， AKT1， STAT3， P-ERK1/ERK2 can be regulated by Baihui (GV20) and Fengchi (GB20).Conclusion: Baihui (GV20) and Fengchi (GB20) can regulate migraine by regulating inflammatory factors and HMOX1， AKT1， STAT3， P-ERK1/ERK2 and other changes in HIF-1 signaling pathway， Signaling by Interleukins and Inflammatory response pathways. Based on systems biology and network pharmacology， and with the model of "acupoint-target-disease"， explore the research methods of systematic acupuncture and moxibustion. We believe this is a usable research direction for exploring the mechanism of acupuncture stimulation.

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Anisotropic transport properties and topological Hall effect in the annealed kagome antiferromagnet FeGe

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Jiajun Ma Chenfei Shi Yantao cao yuwei Zhang Yazhou Li Jiaxing Liao Jialu Wang Wenhe Jiao Hanjie Guo Chenchao Xu Shixun cao Jianhui Dai Jin-ke Bao yuke Li School of Physics Hangzhou Key Laboratory of Quantum Matters Hangzhou Normal University Department of Physics Materials Genome Institute and International Center for Quantum and Molecular StructuresShanghai University Songshan Lake Materials Laboratory School of Physical Science and Technology Lanzhou University key Laboratory of Quantum Precision Measurement of Zhejiang Province Department of Applied PhysicsZhejiang University of Technology

Electron correlation often gives birth to various orders in quantum materials. Recently, a strongly correlated kagome antiferromagnet FeGe is discovered to undergo a charge density wave transition inside the A-type antiferromagnetic state, providing an opportunity to explore the interplay between charge order and magnetism. Here, we reported the observation of anisotropic resistivity and Hall effect, along with a topological Hall effect, in the annealed FeGe crystals. As the current flows along the abplane, the temperature dependence of ρabexhibits a distinct resistivity loop related to a first-order transition at Tcdw. The applied magnetic fields do not alter Tcdwbut can induce a spin-flop transition at Hsf. Consequently, a field-induced large topological Hall effect is observed in the canting antiferromagnetic（CAFM） state below Tcant, which is possibly attributed to the non-trivial spin texture during the spin-flop process. Whereas, as current is parallel to c-axis, both the field-induced transitions in ρcand χcdisappear. Instead, the Hall resistivity in the annealed FeGe significantly exhibits a deviation from the linear *** findings provide valuable insight into revealing the interplay among magnetism, charge order and topology in the kagome magnets.

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