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Micro defects formation and dynamic response analysis of steel plate of quasi-cracking area subjected to explosive load

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Defence Technology（防务技术） 2024年第1期31卷 580-593页

作者： Zheng-qing zhou Ze-chen Du Xiao Wang hui-ling Jiang Qiang zhou Yu-long Zhang Yu-zhe Liu Pei-ze Zhang Research Institute of Macro-Safety Science University of Science and TechnologyBeijing100083China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing100083China School of Mechanical Engineering Nantong UniversityNantong226019China China North Industry Advanced Technology Generalization Institute Beijing100089China China Academy of Ordnance Science China

As the protective component,steel plate had attracted extensive attention because of frequently threats of explosive loads.In this paper,the evolution of microstructure and the mechanism of damage in the quasi-cracking area of steel plate subjected to explosive load were discussed and the relationships between micro defects and dynamic mechanical response were revealed.After the explosion experiment,five observation points were selected equidistant from the quasi-cracking area of the section of the steel plate along the thickness direction,and the characteristics of micro defects at the observation points were analyzed by optical microscope(OM),scanning electron microscope(SEM) and electron backscattered diffraction(EBSD).The observation result shows that many slip bands(SBs) appeared,and the grain orientation changed obviously in the steel plate,the two were the main damage types of micro defects.In addition,cracks,peeling pits,grooves and other lager micro defects were appeared in the lower area of the plate.The stress parameters of the observation points were obtained through an effective numerical model.The mechanism of damage generation and crack propagation in the quasicracking area were clarified by comparing the specific impulse of each observation point with the corresponding micro defects.The result shows that the generation and expansion of micro defects are related to the stress area(i.***.the upper compression area,the neutral plane area,and the lower tension area).The micro defects gather and expand at the grain boundary,and will become macroscopic damage under the continuous action of tensile stress.Besides,the micro defects at the midpoint of the section of the steel plate in the direction away from the explosion center(i.***.the horizontal direction) were also studied.It was found that the specific impulse at these positions were much smaller than that in the thickness direction,the micro defects were only SBs and a few micro cracks,and the those decreased with the increase of the distance from the e

关键词： Explosive load Quasi-cracking area Micro defects Steel plate Dynamic response Numerical simulation

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Clinical review and literature analysis of hepatic epithelioid angiomyolipoma in alcoholic cirrhosis: A case report

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World Journal of Clinical Cases 2024年第14期12卷 2382-2388页

作者： Jing-Qiang Guo Jia-hui zhou Kun Zhang Xin-Liang Lv Chao-Yong Tu Department of Hepatobiliary and Pancreatic Surgery Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina Department of Pathology Lishui Municipal Central HospitalLishui 323000Zhejiang ProvinceChina Department of General Surgery The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND Hepatic epithelioid angiomyolipoma(HEA)has a low incidence and both clinical manifestations and imaging lack specificity.Thus,it is easy to misdiagnose HEA as other tumors of the liver,especially in the presence of liver diseases such as hepatitis cirrhosis.This article reviewed the diagnosis and treatment of a patient with HEA and alcoholic cirrhosis,and analyzed the literature,in order to improve the understanding of this disease.CASE SUMMARY A 67-year-old male patient with a history of alcoholic cirrhosis was admitted due to the discovery of a space-occupying lesion in the liver.Based on the patient’s history,laboratory examinations,and imaging examinations,a malignant liver tumor was considered and laparoscopic partial hepatectomy was performed.Postoperative pathology showed HEA.During outpatient follow-up,the patient showed no sign of recurrence.CONCLUSION HEA is difficult to make a definite diagnosis before surgery.HEA has the poten-tial for malignant degeneration.If conditions permit,surgical treatment is recom-mended.

关键词： Hepatic epithelioid angiomyolipoma Alcoholic cirrhosis Magnetic resonance imaging Computed tomography Immunohistochemistry Misdiagnose analysis Case report

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Comparison of nonlinear modeling methods for the composite rubber clamp

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 763-778页

作者： Yiming CAO hui MA Xumin GUO Bingfeng ZHAO hui LI Xin WANG Bing WANG School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Key Laboratory of Vibration and Control of Aero-Propulsion Systems of Ministry of Education of China Northeastern UniversityShenyang 110819China AVIC Shenyang Engine Design Institute Shenyang 110013China Dalian Mengyu Machinery Co. Ltd.Dalian 116317Liaoning ProvinceChina

The cubic stiffness force model(CSFM)and Bouc-Wen model(BWM)are introduced and compared innovatively.The unknown coefficients of the nonlinear models are identified by the genetic algorithm combined with experiments.By fitting the identified nonlinear coefficients under different excitation amplitudes,the nonlinear vibration responses of the system are predicted.The results show that the accuracy of the BWM is higher than that of the CSFM,especially in the non-resonant region.However,the optimization time of the BWM is longer than that of the CSFM.

关键词： pipeline system nonlinear clamp model composite rubber clamp amplitude-dependent characteristic vibration response experiment

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Critical Role of Ethylene-Propylene Block Copolymer in Impact Polypropylene Copolymer

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Chinese Journal of Polymer Science 2024年第3期42卷 344-351,I0007页

作者： Yu-hui Tang Na Zhang Wei Bao Wei Jiang Yuan Lin Zhao-hui Su 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

Ethylene-propylene block copolymer(EbP) is a vital component in impact polypropylene copolymer(IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work,four IPCs were investigated by atomic force microscopy-infrared(AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose EbP comprises long P and long E segments, the EbP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the E-P segmented copolymer(EsP). In contrast, in the IPC with EbP composed of long P and short E segments, the EbP fraction formed an outer shell for the rubber particles with the cores comprising the EsP alone, and this IPC, containing a lower E comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of EbP governs the phase morphology in IPC, which in turn impacts the properties of the composite material.

关键词： Impact polypropylene copolymers AFM-IR Ethylene-propylene block copolymers Core-shell rubber particles

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Multi-Level Parallel Network for Brain Tumor Segmentation

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 741-757页

作者： Juhong Tie hui Peng School of Software Engineering Chengdu University of Information TechnologyChengdu610225China

Accurate automatic segmentation of gliomas in various sub-regions,including peritumoral edema,necrotic core,and enhancing and non-enhancing tumor core from 3D multimodal MRI images,is challenging because of its highly heterogeneous appearance and shape.Deep convolution neural networks(CNNs)have recently improved glioma segmentation performance.However,extensive down-sampling such as pooling or stridden convolution in CNNs significantly decreases the initial image resolution,resulting in the loss of accurate spatial and object parts information,especially information on the small sub-region tumors,affecting segmentation performance.Hence,this paper proposes a novel multi-level parallel network comprising three different level parallel subnetworks to fully use low-level,mid-level,and high-level information and improve the performance of brain tumor segmentation.We also introduce the Combo loss function to address input class imbalance and false positives and negatives imbalance in deep learning.The proposed method is trained and validated on the BraTS 2020 training and validation dataset.On the validation dataset,ourmethod achieved a mean Dice score of 0.907,0.830,and 0.787 for the whole tumor,tumor core,and enhancing tumor core,respectively.Compared with state-of-the-art methods,the multi-level parallel network has achieved competitive results on the validation dataset.

关键词： Convolution neural network brain tumor segmentation parallel network

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Rogue waves for the(2+1)-dimensional Myrzakulov–Lakshmanan-IV equation on a periodic background

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Communications in Theoretical Physics 2024年第4期76卷 32-42页

作者： Xiao-hui Wang Zhaqilao College of Mathematics Science Inner Mongolia Normal UniversityHohhot 010022China Laboratory of Infinite-dimensional Hamiltonian System and Its algorithm Application Hohhot 010022China Center for Applied Mathematical Science Inner MongoliaHohhot 010022China

In this paper,the rogue wave solutions of the(2+1)-dimensional Myrzakulov–Lakshmanan(ML)-IV equation,which is described by five component nonlinear evolution equations,are studied on a periodic background.By using the Jacobian elliptic function expansion method,the Darboux transformation(DT)method and the nonlinearization of the Lax pair,two kinds of rogue wave solutions which are expressed by Jacobian elliptic functions dn and cn,are obtained.The relationship between these five kinds of potential is summarized systematically.Firstly,the periodic rogue wave solution of one potential is obtained,and then the periodic rogue wave solutions of the other four potentials are obtained directly.The solutions we find present the dynamic phenomena of higher-order nonlinear wave equations.

关键词： rogue waves on a periodic background (2+1)-dimensional Myrzakulov-Lakshmanan-IV equation Darboux transformation Jacobian elliptic function

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Height and body mass index trajectories from 1975 to 2015 and prevalence of stunting,underweight and obesity in 2016 among children in Chinese cities:findings from five rounds of a national survey

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World Journal of Pediatrics 2024年第4期20卷 404-412页

作者： Xin‑Nan Zong hui Li Ya‑Qin Zhang Department of Growth and Development Capital Institute of PediatricsBeijing 100020China

Background A more comprehensive assessment of growth and nutrition in children is required in China due to rapid socioeconomic processes.We aimed to investigate height and body mass index(BMI)trajectories from 1975 to 2015 and the prevalence of stunting and obesity in 2016 among children in Chinese cities.Methods A total of 904,263 children from birth to 6.9 years were collected from a series of nationally representative surveys in China.Height and BMI trajectories and prevalence of stunting,underweight,overweight and obesity were assessed.Results The average height level of Chinese urban children under 7 years presented a positive secular trend from 1975 to 2015;however,a slowing tendency occurred in 2005‒2015.An apparent increase was observed at the 5th,50th and 95th percentiles of BMI in urban children aged 3 years and older,with a more prominent increase at the 95th percentile.The total prevalence of stunting and underweight under 7 years was 1.4%and 2.0%,respectively.The total prevalence of overweight and obesity under 7 years was 12.6%and 4.3%,respectively,with 12.7%and 4.9%for boys,12.6%and 3.6%for girls,12.1%and 4.0%in urban areas and 13.1%and 4.5%in suburban rural areas.Conclusions The average height level of Chinese urban children has reached World Health Organization child growth standards since 2005 and presented a slowing tendency in secular trend in 2005‒2015.More attention and efforts and public health interventions should be urgently made to combat overweight and obesity among preschool children.

关键词： Body mass index Children Height Obesity Stunting

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B-cell lymphoma-2 phosphorylation at Ser70 site-related autophagy mediates puerarin-inhibited the apoptosis of MC3T3-E1 cells during osteoblastogenesis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 27-34页

作者： LI Xi LIN Xiangquan CHEN Dongdong LIU hui the Third Clinical Medical College Fujian Medical University Department of Orthopedics Fuzhou Second HospitalFuzhou 350007China

OBJECTIVE:To explore the relationship between autophagy and apoptosis regulated by puerarin during osteoblastogenesis.METHODS:In this study,the effects of puerarin on the autophagic activity and apoptosis level of osteoblast precursors(MC3T3-E1 cells)was observed.Subsequently,the roles of puerarin on B-cell lymphoma-2(Bcl-2)phosphorylation at different sites in osteoblast precursors were observed.The effect of puerarin on the interaction between Bcl-2 and autophagy regulatory molecule or pro-apoptotic molecule was also investigated using Co-immunoprecipitation assays.In addition,the effect of puerarin on mitochondrial membrane potential of osteoblast precursors was also identified by mitochondrial membrane potential fluorescence probe assays.RESULTS:Our results showed that puerarin can promote the autophagic activity and apoptosis level of MC3T3-E1cells.In addition,puerarin promoted Bcl-2phosphorylation at Ser70 site,and the dissociation of Bcl-2-Beclin1 complex.Moreover,puerarin could enhance the binding of Bcl-2-Bcl-2-Associated X(Bax)complex in MC3T3-E1 cells.Furthermore,puerarin increased the mitochondrial membrane potential of MC3T3-E1 cells.CONCLUSIONS:Therefore,puerarin promotes Beclin1into autophagy flux through Bcl-2 phosphorylation at Ser70,thereby enhancing autophagy of osteoblast precursors,which mediates its anti-apoptotic role during osteoblastogenesis.Furthermore,the dissociation of Bcl-2-Beclin1 complex is conducive to the binding of Bcl-2-Bax complex,which resists the apoptosis of osteoblast precursors via the increased mitochondrial membrane potential.

关键词： puerarin osteoblasts autophagy apoptosis lymphoma B-cell

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Adaptive composite anti-disturbance control for heavy haul trains

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Transportation Safety and Environment 2024年第1期6卷 75-82页

作者： Longsheng Chen hui Yang School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang 33013JiangxiChina School of Aircraft Engineering Nanchang Hangkong UniversityNanchang 330063JiangxiChina

In this paper,an adaptive composite anti-disturbance control of heavy haul trains(HHTs)is proposed.First,the mechanical principle and characteristics of couplers are analysed and the longitudinal multi-particles nonlinear dynamic model of HHTs is established,which can satisfy that the forces of vehicles in different positions are different.Subsequently,a radial basis function network(RBFNN)is employed to approximate the uncertainties of HHTs,and a nonlinear disturbance observer(NDO)is constructed to estimate the approximation error and external disturbances.To indicate and improve the approximation accuracy,a serial-parallel identification model of HHTs is constructed to generate a prediction error,and an adaptive composite anti-disturbance control scheme is developed,where the prediction error and tracking error are employed to update RBFNN weights and an auxiliary variable of NDO.Finally,the feasibility and effectiveness of the proposed control scheme are demonstrated through the Lyapunov theory and simulation experiments.

关键词： heavy haul train(HHT) radial basis function neural network nonlinear disturbance observer(NDO) serial-parallel identification model composite anti-disturbance control

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Regulation of solvation structure and the cooperation environment of potassium bonds for wider-temperature adaptive potassium storage

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Rare Metals 2024年第4期43卷 1610-1621页

作者： Bing-Bing Liu Yi-hui Liu You-Bin Zhang Zhen-Guo Qi Guo-hui Qin State Key Laboratory Base for Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and Technology Shandong Synergetic Innovation Center of Ecological and Chemical Engineering

Antimony selenide（Sb2Se3） is one of the perspective candidates for potassium-ion batteries due to its advanced virtues stem including featured high capacity,fertile reserves and the relative narrow band gap.Despite the unique advantages,it is still plagued by the unstable interface compatibility and poor wider-temperature adaptability.The optimization of microstructure and the construction of inorganic-organic hybrids with a low desolvation barrier and rapid kinetics behaviors are efficient to address these issues.The Sb2Se3nanorods enclosed by the S-doped carbon layer（SC）,further crosslinked by the poly（N-isopropylacrylamide）(PM) film（PM@Sb2Se3@SC）,were artificially fabricated,and it displays the enrichment ion aggregated model as well as contacted ion pair state,the well-tailored cooperation environment of potassium bonds,assuring a homogeneous potassium deposition and an excellent widertemperature adaptability.The complicated experimental studies and theoretical calculations authenticate the synergistic effects of geometric conformation and compositional design for the tremendously enhanced potassium storage.Moreover,the full device over PM@Sb2Se3@SC anode and the potassium Prussian blue cathode manifests impressively durable cycling life and wider-temperature adaptability,verifying the glorious contribution from the finely manipulation in solvation structure and potassium bonds to enhancing the potassium storage behaviors.

关键词： Anode Sb 2 Se 3 rods Interface compatibility Inorganic–organic electrode Potassium ion battery

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