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Journal of Electronic Science and Technology of China 2007年第4期5卷 303-307页

作者： Wen-feng qin Jun zhu Jie Xiong Jin-Long Tang Xiao feng State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of China （UESTC） Chcngdu 610054 China

Epitaxial Ba0.6Sr0.4TiO3 （BST） thin films were deposited on LaAlO3 （LAO） substrates with the conductive metallic oxide La0.5 Sr0.5CoO3 （LSCO） film as a bottom electrode by pulsed laser deposition （PLD）. X-ray diffraction 0-20 andФ scan showed that the epitaxial relationship of BST/LSCO /LAO was [001] BST// [001] LSCO//[001] LAO. The atomic force microscope （AFM） revealed a smooth and crack-free surface of BST films on LSCO-coated LAO substrate with the average grain size of 120 nm and the RMS of 1.564 nm for BST films. Pt/BST/LSCO capacitor was fabricated to perform Capacitance-Voltage measurement indicating good insulating characteristics. For epitaxial BST film, the dielectric constant and dielectric loss were determined as 471 and 0.03, respectively. The tunabilty was 79.59% and the leakage current was 2.63×10^-7 A/cm^2 under an applied filed of 200 kV/cm. Furthermore, it was found that epitaxial BST （60/40） fdms demonstrate well-behaved ferroelectric properties with the remnate polarization of 6.085μC/cm^2 and the coercive field of 72 kV/cm. The different electric properties from bulk BST （60/40） materials with intrinsic paraelectric characteristic are attributed to the interface effects.

关键词： BST electrode LSCO thin film.

Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers

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China Ocean Engineering 2024年第2期38卷 285-296页

作者： DU Zun-feng zhu Hai-ming YU Jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real *** problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration ***,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known *** study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal *** the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

Ex vivo liver resection and auto-transplantation as an alternative for the treatment of liver malignancies: Progress and challenges

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 117-122页

作者： Xin Yang Lu Lu Wen-Wei zhu Yi-feng Tao Cong-Huan Shen Jin-Hong Chen Zheng-Xin Wang Lun-Xiu qin Hepatobiliary Surgery and Liver Transplantation Centers Department of General SurgeryHuashan Hospital&Cancer Metastasis InstituteFudan UniversityShanghai 200040China

Hepatectomy is still the major curative treatment for patients with liver ***,it is still a big challenge to remove the tumors in the central posterior area,especially if their location involves the retrohepatic inferior vena cava and hepatic *** vivo liver resection and auto-transplantation(ELRA),a hybrid technique of the traditional liver resection and transplantation,has brought new hope to these patients and therefore becomes a valid alternative to liver *** to its technical difficulty,ELRA is still concentrated in a few hepatobiliary centers that have experienced surgeons in both liver resection and liver *** efficacy and safety of this technique has already been demonstrated in the treatment of benign liver diseases,especially in the advanced alveolar ***,the application of ELRA for liver malignances has gained more ***,standardization of clinical practice norms and international consensus are still *** prognostic impact in these oncologic patients also needs further *** this review,we summarized the principles and recent progresses on ELRA.

关键词： Ex vivo liver resection Liver auto-transplantation Oncology Liver malignancies

Effect of trigger system on experimental dispersion characteristics of active surface wave testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 311-318页

作者： Lin Shibin Jeramy C.Ashlock zhu Liming qin Zexiang Li Bo zhu Xingji Zhai Changhai State Key Laboratory of Precision Blasting Jianghan UniversityWuhan 430056China Hubei Key Laboratory of Blasting Engineering Jianghan UniversityWuhan 430056China Department of Civil Construction&Environmental EngineeringIowa State UniversityAmesIA 50010USA Wuhan Airport Road Development Co. Ltd.Wuhan 430065China School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen 518055China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disaster of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin 150090China

A trigger system is typically employed in active seismic testing to trigger and synchronize multichannel surface wave data *** effect of the trigger system on the dispersion image of surface waves is empirically known to be negligible,however,theoretical explanation regarding the effect of the trigger system is *** study systematically examines the theory for surface wave dispersion analysis and proves that the effect of the trigger system on a dispersion image is negligible via a solid theoretical ***,based on the new theoretical explanation,an alternative method that uses only the relative phase difference between sensors to extract dispersion characteristics with better conceptual clarity is *** active surface wave testing cases are considered to validate the theory and *** results indicate that(1)an accurate trigger system is not necessary for surface wave data acquisition,and(2)it is unnecessary to assume that the impact point is the generation point of the surface waves for the experimental dispersion analysis.

关键词： site investigation surface waves data acquisition dispersion

Hot Deformation Behavior and Microstructures Evolution of GNP-Reinforced Fine-Grained Mg Composites

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 407-424页

作者： Hengrui Hu Jiayu qin Yunpeng zhu Jinhui Wang Xiaoqiang Li Peipeng Jin qinghai Provincial Key Laboratory of New Light Alloys Qinghai UniversityXining 810016China qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and Forming Qinghai UniversityXining 810016China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China School of Material Science and Engineering Lanzhou University of TechnologyLanzhou 730050China

Graphene nanoplates(GNPs)-reinforced magnesium matrix composites have been attracted great ***,knowledge is lack for the hot deformation behavior of GNP-reinforced magnesium(GNPs/Mg)*** this study,the fine-grained GNPs/Mg composite was fabricated by powder metallurgy process followed by *** hot deformation behavior,microstructure evolution and dynamic recrystallization(DRX)mechanism of fine-grained GNPs/Mg composite were investigated by hot compression test and electron back-scatter diffraction(EBSD).The hot compression tests of the composite were conducted at temperatures between 423 and 573 K with the strain rates from 0.001 to 1 s^(-1).The strain compensated power law equation was established to describe the hot deformation behavior of the *** stress exponent and activation energy of the composite are 7.76 and 83.23 kJ/mol,respectively,suggesting that the deformation mechanism is grain boundary slip controlled dislocation climb *** abnormally high stress exponent and activation energy are unattainable in the composite due to the fine grain size of the composites and the absence of Zener pinning and Orowan effects of GNPs *** grain size increases with the decrease in Zener-Hollomn(Z)parameter,which can be well fitted by power-law *** the increase in grain size and decrease in Z parameter,the geometrically necessary dislocation density decreases,which shows the approximately power-law relationship.A random and weak texture was formed after hot *** discontinuous dynamic recrystallization and continuous dynamic recrystallization mechanism dominated the DRX behavior at 473 K/0.001 s^(-1) and 573 K/0.001 s^(-1),respectively.

关键词： GNPs Mg composite Hot deformation behavior Constitutive equations Microstructure evolution Dynamic recrystallization

Enhancing the mechanical properties of casting eutectic high -entropy alloys via W addition

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1364-1372页

作者： Xu Yang Dezhi Chen Li feng Gang qin Shiping Wu Ruirun Chen National Key Laboratory for Precision Hot Processing of Metals School of Material Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

The effect of W element on the microstructure evolution and mechanical properties of Al_(1.25)CoCrFeNi3 eutectic high-entropy alloy and Al_(1.25)CoCrFeNi_(3-x)W_(x)(x=0,0.05,0.1,0.3,and 0.5;atomic ratio)high-entropy alloys(HEAs)were *** show that the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs are composed of face-centered cubic and body-centered cubic(BCC)*** W content increases,the microstructure changes from eutectic to *** addition of W lowers the nucleation barrier of the BCC phase,decreases the valence electron concentration of the HEAs,and replaces Al in the BCC phase,thus facilitating the nucleation of the BCC *** results show that the addition of W greatly improves the mechanical properties,and solid-solution,heterogeneous-interface,and second-phase strengthening are the main strengthening *** yield strength,tensile strength,and elongation of the Al_(1.25)CoCrFeNi2.95W0.05 HEA are 601.44 MPa,1132.26 MPa,and 15.94%,respectively,realizing a balance between strength and *** fracture mode of the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs is ductile–brittle mixed fracture,and the crack propagates and initiates in the BCC *** eutectic lamellar structure impedes crack propagation and maintains plasticity.

关键词： high-entropy alloy microstructure mechanical property fracture behavior

Fracture mechanism of inclusions in thick plate center under tensile loading

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Journal of Iron and Steel Research International 2024年第5期31卷 1196-1209页

作者： Lei Hu Li-qin Zhang feng Hu Guo-hong Zhang Kuan Zheng Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan430081HubeiChina Department of Applied Physics Wuhan University of Science and TechnologyWuhan430081HubeiChina Analysis and Testing Center Wuhan University of Science and TechnologyWuhan430081HubeiChina

Segregation of solute atoms in the center of thick plates of the tempered steel can cause an inhomogeneous structural transformation and generate micron-sized inclusions,which leads to lamellar tearing of thick plate and decreases the plasticity and *** formation and fragmentation mechanisms of micron-sized inclusions,like MnS and(Nb,Ti)C,in the center of thick plates were investigated by using thermodynamic calculations,finite element simulations,and electron backscatter diffraction characterization *** results show that micron-sized inclusions nucleate and grow in the liquid phase,and under tensile loading,they exhibit three fragmentation *** local stress during the fragmentation of inclusions is lower than the critical fracture stress of adjacent grains,and phase boundaries can effectively impede crack propagation into the *** existence of a low proportion of high-angle grain boundaries(58.1%)and high Kernel average misorientation value(0.534°)in the segregation band promotes inclusions fragmentation and crack *** difference in crack initiation and propagation direction caused by the morphology of inclusions and physical properties,as well as different matrix arrest abilities,is the main reasons for the diversity of inclusion fragmentation.

关键词： Thick plate Inclusion Finite element simulation Critical fracture stress Fracture mechanism

Improved observation of colonized roots reveals the regulation of arbuscule development and senescence by drought stress in the arbuscular mycorrhizae of citrus

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Horticultural Plant Journal 2024年第2期10卷 425-436页

作者： Xilong Yin Wei Zhang Zengwei feng Guangda feng Honghui zhu qing Yao College of Horticulture South China Agricultural UniversityKey Laboratory of Biology and Genetic Improvement of Horticultural Crops(South China)Ministry of Agriculture and Rural AffairsGuangdong Province Key Laboratory of Microbial Signals and Disease ControlGuangzhouGuangdong 510642China Key Laboratory of Agricultural Microbiomics and Precision Application Ministry of Agriculture and Rural AffairsGuangdong Provincial Key Laboratory of Microbial Culture Collection and ApplicationKey Laboratory of Agricultural MicrobiomicsState Key Laboratory of Applied Microbiology Southern ChinaGuangdong Microbial Culture Collection Center(GDMCC)Institute of MicrobiologyGuangdong Academy of SciencesGuangzhouGuangdong 510070China

Citrus is the typical mycorrhizal fruit tree species establishing symbiosis with arbuscular mycorrhizal (AM) fungi. However, arbuscule development and senescence in colonized citrus roots, especially in response to drought stress, remain unclear, which is mainly due to the difficulty in clearing and staining lignified roots with the conventional method. Here, we improved the observation of colonized roots of citrus plants with the sectioning method, which enabled the clear observation of AM fungal structures. Furthermore, we investigated the effects of one week of drought stress on arbuscule development and senescence with the sectioning method. Microscopy observations indicated that drought stress significantly decreased mycorrhizal colonization (F%and M%) although it did not affect plant growth performance. Fluorescence probes (WGA 488 and/or Nile red) revealed that drought stress inhibited arbuscule development by increasing the percentage of arbuscules at the early stage and decreasing the percentages of arbuscules at the midterm and mature stages. Meanwhile, drought stress accelerated arbuscule senescence, which was characterized by the increased accumulation of neutral lipids. Overall, the sectioning method developed in this study enables the in-depth investigation of arbuscule status, and drought stress can inhibit arbuscule development but accelerate arbuscule senescence in the colonized roots of citrus plants. This study paves the way to elaborately dissecting the arbuscule dynamics in the roots of fruit tree species in response to diverse abiotic stresses.

关键词： Arbuscular mycorrhizae Citrus Drought stress Arbuscule development Arbuscule senescence Fruit tree species

Machine learning assisted adsorption performance evaluation of biochar on heavy metal

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 29-42页

作者： Qiannan Duan Pengwei Yan Yichen feng Qianru Wan Xiaoli zhu Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity College of Urban and Environmental SciencesNorthwest UniversityXi’an710127China Department of Environment Science Shaanxi Normal UniversityXi’an710062China

Heavy metals(HMs)represent pervasive and highly toxic environmental pollutants,known for their long latency periods and high toxicity levels,which pose significant challenges for their removal and ***,the removal of heavy metals from the environment is crucial to ensure the water *** materials,known for their intricate pore structures and abundant oxygen-containing functional groups,are frequently harnessed for their effectiveness in mitigating heavy metal ***,conventional tests for optimizing biochar synthesis and assessing their heavy metal adsorption capabilities can be both costly and *** address this challenge,this paper proposes a data-driven machine learning(ML)approach to identify the optimal biochar preparation and adsorption reaction conditions,with the ultimate goal of maximizing their adsorption *** utilizing a data set comprising 476 instances of heavy metal absorption by biochar,seven classical integrated models and one stacking model were trained to rapidly predict the efficiency of heavy metal adsorption by *** predictions were based on diverse physicochemical properties of biochar and the specific adsorption reaction *** results demonstrate that the stacking model,which integrates multiple algorithms,allows for training with fewer samples to achieve higher prediction accuracy and improved generalization ability.

关键词： Machine learning Biochar Heavy metal Adsorption efficiency

Dual peroxisome proliferator-activated receptorα/δagonists:Hope for the treatment of alcohol-associated liver disease?

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World Journal of Gastroenterology 2024年第37期30卷 4163-4167页

作者： Xin-Yang Zhang qin-Jun-Jie Chen feng zhu Min Li Dan Shang Department of Vascular Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina Department of Hepatobiliary Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina Department of Vascular Surgery Hubei Provincial Hospital of Traditional Chinese MedicineWuhan 430061Hubei ProvinceChina

In this letter,we review the article“Effects of elafibranor on liver fibrosis and gut barrier function in a mouse model of alcohol-associated liver disease”.We focus specifically on the detrimental effects of alcohol-associated liver disease(ALD)on human *** its insidious onset and increasing incidence,increasing awareness of ALD can contribute to reducing the prevalence of liver *** comprises a spectrum of several different disorders,including liver steatosis,steatohepatitis,fibrosis,cirrhosis,and hepatocellular *** pathogenesis of ALD is exceedingly *** studies have shown that peroxisome proliferator-activated receptors(PPARs)regulate lipid metabolism,glucose homeostasis and inflammatory responses within the ***,their dysfunction is a major contributor to the progression of *** is an oral,dual PPARαandδ*** effectiveness of elafibranor in the treatment of ALD remains *** this letter,we emphasize the harm of ALD and the burden it places on ***,we summarize the clinical management of all stages of ALD and present new insights into its pathogenesis and potential therapeutic ***,we discuss the mechanisms of action of PPARαandδagonists,the significance of their antifibrotic effects on ALD and future research directions.

关键词： Alcohol-associated liver disease Fibrosis Antifibrotic effect Elafibranor Peroxisome proliferator-activated receptor