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Evolution mechanism and quantitative characterization of initial micro-cracks in marble under triaxial compression

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第7期25卷 586-595页

作者： Zhiliang wang Songyu LI Jianguo wang Ao LI Weixiang wang Chenchen FENG Jingjing FU School of Civil Engineering Hefei University of TechnologyHefei230009China School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou221116China

The initial micro-cracks affect the evolution characteristics of macroscopic deformation and failure of rock but are often ignored in theoretical calculation,numerical simulation,and mechanical *** this study,we propose a quantitative analysis model to investigate the effects of initial micro-cracks on the evolution of marble deformation and *** relationship between the micro-crack propagation and the marble failure characteristics was comprehensively studied by combining theoretical analysis with a micro-computed tomography(micro-CT)scanning *** found that with the increase of confining pressure,the matrix elastic modulus of the marble first increased and then tended to be stable,while the micro-cracks increased *** sensitivity ranges of the marble sample matrix elastic modulus and micro-cracks to confining pressure were 0–30 MPa and 30–50 MPa,*** porosity and Poisson’s ratio decreased *** increasing proportion of internal micro-cracks led to an increase in the sample *** samples presented mainly shear failure under triaxial compression,and the failure angle decreased linearly with the increase of confining *** convergence direction of cracks decreased *** quantitative analysis model could accurately portray the relationship between the overall macroscopic deformation and the deviatoric stress of the samples at the compaction and the linear elastic stages,thus deepening the understanding of the stress–strain behavior of rocks.

关键词： Marble Initial micro-cracks Triaxial compression Constitutive relationship Crack evolution

Structural characteristics and tectonic division of the Zambezi Delta basin in the offshore East Africa:evidences from gravity and seismic data

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Acta Oceanologica Sinica 2024年第4期43卷 105-118页

作者： Guozhang Fan Wen Li Liangbo Ding Wanyin wang Hongping wang Dingding wang Lin Li Hao wang Chaofeng wang Qingluan wang Ying Zhang Hangzhou Research Institute of Petroleum Geology PetroChinaHangzhou 310023China College of Geological Engineering and Geomatics Chang’an universityXi’an 710054China Key Laboratory of Marine Geology and Environment Chinese Academy of SciencesQingdao 266071China National Engineering Research Center of Offshore Oil and Gas Exploration Beijing 100028China Department of Earth Environment and Resources SciencesUniversity of Naples FedericoⅡNaples 80138Italy

The Zambezi Delta basin is a passive marginal basin located on the East African coast that has good oil and gas exploration *** to the special geological evolutionary background of the Beira High in the Zambezi Delta basin,it has a low gravity anomaly,and the existing seismic survey lines do not cover the whole basin;therefore,it is difficult to interpret the structural characteristics of the whole basin based solely on gravity or seismic *** on satellite altimetry gravity anomaly data,this study infers the distribution characteristics of faults in the Zambezi Delta basin by using the normalized vertical derivative of the total horizontal derivative(NVDR-THDR)***,constrained by seismic data,the gravity anomaly at the Moho interface is extracted by using the fast forward method of the double-interface model of the gravity anomaly,and this anomaly is then removed from the Bouguer gravity anomaly to obtain the sedimentary layer gravity *** thickness of the sedimentary strata is obtained by inversing the sedimentary basement depth of the whole ***,uplifts and depressions are divided based on a sedimentary layer thickness of 3 *** research demonstrates that the Zambezi Delta basin mainly features nearly SN-trending and NE-trending faults and that these faults exhibit east-west *** nearly SN-trending strike-slip faults controlled the sedimentary development of the basin,and the NE-trending tensile faults may have acted as migration channels for oil,gas and ***“overcompensation”effect of the Moho interface gravity anomaly on the gravity anomaly of the sedimentary layer is caused by the depression of the Moho interface beneath the Beira High,which results in a low gravity anomaly value for the Beira *** pattern of uplifts and depressions trends NE and has the structural characteristics of east-west blocks.

关键词： Zambezi Delta basin satellite altimetry gravity anomaly Beira High fault division uplift and depression pattern

Cushioning Performance of a Novel Polyurethane Foam Material Applied in Fragile Packaging

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Acta Mechanica Solida Sinica 2024年第3期37卷 487-497页

作者： Huifeng Xi Chunqiu Guo Jinbiao Yang Xiaogang wang Bowei wang Shiqing Huang Zhiwei wang School of Mechanics and Construction Engineering Jinan UniversityGuangzhou510632China College of Packing Engineering Jinan UniversityZhuhai519070China MOE Key Lab of Disaster Forecast and Control in Engineering Jinan UniversityGuangzhou510632China Foshan Soft Valley Technology Co. Ltd.Foshan528000China

For fragile products,packaging requires cushioning protection to prevent irreversible damage from accidental falls,transportation impacts,and other *** new polyurethane foam(PUF)material demonstrates superior cushioning and vibration isolation performance in practical applications,effectively minimizing damage from *** and vibration experiments were conducted on packages comprising novel PUF,expandable polyethylene,ethylene-vinyl acetate copolymer foam,and *** verify that the new PUF material outperforms in cushioning and vibration isolation,as observed from the acceleration ***,a random vibration analysis of a packaging unit involving different thicknesses of PUF materials and bracelets reveals the enhanced vibration isolation effect within a specific thickness *** vibration results of the bracelet’s outer packaging align closely with finite element simulation results,validating the effectiveness of designing and optimizing the outer *** finite element simulation,deeper understanding and prediction of the bracelet’s vibration response under various conditions is achieved,facilitating optimized packaging design for better protection and vibration damping.

关键词： Flexible polyurethane foam Packaging of fragile goods Nonlinear dynamics Vibration frequency Finite element simulation

Prenatal prednisone exposure disturbs fetal kidney development and its characteristics

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Journal of Environmental Sciences 2024年第11期145卷 75-87页

作者： Zhiping Xia Songdi wang Wen wang Yutang Liu Tianshu Yang Hui wang Ying Ao Department of Pharmacology Wuhan University School of Basic Medical SciencesWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease Wuhan 430071China

Prednisone is a synthetic glucocorticoid that is commonly used in both human and veterinary ***,it is also recognized as an emerging environmental *** be exposed to prednisone actively or passively throughmultiple pathways and cause developmental toxicity to the ***,the impact of prenatal prednisone exposure(PPE)on fetal kidney development remains *** this study,pregnant mice were administered prednisone intragastrically during full-term pregnancy with different doses(0.25,0.5,or 1 mg/(kg·day)),or at the dose of 1 mg/(kg·day)in different gestational days(GD)(GD0-9,GD10-18,or GD0-18).The pregnant mice were euthanized on *** staining revealed fetal kidney dysplasia,with an enlarged glomerular Bowman’s capsule space and a reduced capillary network in the PPE *** expression of the podocyte and the mesangial cell marker genes was significantly reduced in the PPE ***,overall gene expression in renal tubules and collecting ducts were markedly *** of the above effects were more pronounced in high-dose,full-term pregnancy,and female *** on the mechanism of the female fetal kidney have revealed that PPE reduced the expression of Six2,increased the expression of Hnf1β,Hnf4α,and Wnt9b,and inhibited the expression of glial cell line-derived neurotrophic factor(GDNF)and Notch signaling *** conclusion,this study demonstrated that there is a sex difference in the developmental toxicity of PPE to the fetal kidney,and the time effect is manifested as full-term pregnancy>early pregnancy>mid-late pregnancy.

关键词： Prenatal prednisone exposure Kidney developmental toxicity Glomerulus Toxicity characteristics

Research on Fiber Optic Surface Plasmon R ***:A Review

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Photonic Sensors 2024年第2期14卷 1-30页

作者： Qi wang Dianyun ZHANG Yizhuo QIAN Xiangyu YIN Lei wang Shushuai ZHANG Yuyang wang State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China College of Information Science and Engineering Northeastern UniversiyShenyang 110819China Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Qinhuangdao 066004China State Key Laboratory of Chemo/Biosensing and Chemometrics Hunan UniversityChangsha 410082China

Due to the benefits of the high sensitivity,real-time response,no labeling requirement,and good selectivity,fiber optic sensors based on surface plasmon resonance(SPR)have gained popularity in biochemical sensing in recent *** current research on such sensors is hot in enhancing sensitivity,improving detection accuracy,and achieving the detection of biochemical *** goal of this work is to present a thorough overview of recent developments in the optical fiber SPR biosensor ***,it explores the basic principles and sensing structures of optical fiber SPR biosensors,focusing on four ***,this paper introduces three fiber optic surface plasmon biosensors:SPR,localized surface plasmon resonance(LSPR),and long-range surface plasmon resonance(LRSPR).Each concept is explained from the perspective of the basic principles of fiber optic SPR ***,a classification of fiber optic SPR biosensors in health monitoring,food safety,environmental monitoring,marine detection,and other applications is introduced and ***,this paper summarizes the current research directions of SPR ***,it provides a prospective outlook on how fiber optic SPR sensors will develop in the future.

关键词： Surface plasmon resonance biosensors optical fiber sensors sensitivity

Tribological properties of PTFE-based fabric composites at cryogenic temperature

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Friction 2024年第2期12卷 245-257页

作者： Mingkun XU Zidan wang Lihe GUO Liming TAO Tianbao MA Tingmei wang Qihua wang Key Laboratory of Science and Technology on Wear and Protection of Materials Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Fabric composites are widely employed in self-lubricating bearing liners as solid lubrication *** the tribological behaviors of fabric composites have been extensively studied,the cryogenic tribological properties and mechanisms have been scarcely reported and are largely unclear to instruct material design for aerospace and other high-tech ***,the tribological properties of polytetrafluoroethylene(PTFE)-based hybrid-fabric composites were investigated at cryogenic and ambient temperatures in the form of pin-on-disk friction under heavy *** results suggest that the friction coefficients of the hybrid-fabric composites obviously increase with a decrease in wear when the temperature drops from 25 to−150°***,thermoplastic polyetherimide(PEI),as an adhesive for fabric composites,has better cryogenic lubrication performance than thermosetting phenol formaldehyde(PF)resin,which can be attributed to the flexible chemical structure of *** excellent lubrication performance of hybrid-fabric composites is attributed to the transfer film formed by PTFE fibers on the surface of fabrics.

关键词： cryogenic temperatures fabric composites friction and wear transfer film

Self-supervised recalibration network for person re-identification

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Defence Technology（防务技术） 2024年第1期31卷 163-178页

作者： Shaoqi Hou Zhiming wang Zhihua Dong Ye Li Zhiguo wang Guangqiang Yin Xinzhong wang Shenzhen Institute of Information Technology Shenzhen518172China University of Electronic Science and Technology of China Chengdu611731China Kash Institute of Electronics and Information Industry Kashi844099China

The attention mechanism can extract salient features in images,which has been proved to be effective in improving the performance of person re-identification(Re-ID).However,most of the existing attention modules have the following two shortcomings:On the one hand,they mostly use global average pooling to generate context descriptors,without highlighting the guiding role of salient information on descriptor generation,resulting in insufficient ability of the final generated attention mask representation;On the other hand,the design of most attention modules is complicated,which greatly increases the computational cost of the *** solve these problems,this paper proposes an attention module called self-supervised recalibration(SR)block,which introduces both global and local information through adaptive weighted fusion to generate a more refined attention *** particular,a special"Squeeze-Excitation"(SE)unit is designed in the SR block to further process the generated intermediate masks,both for nonlinearizations of the features and for constraint of the resulting computation by controlling the number of ***,we combine the most commonly used Res Net-50 to construct the instantiation model of the SR block,and verify its effectiveness on multiple Re-ID datasets,especially the mean Average Precision(m AP)on the Occluded-Duke dataset exceeds the state-of-the-art(SOTA)algorithm by 4.49%.

关键词： Person re-identification Attention mechanism Global information Local information Adaptive weighted fusion

A Study on the Impact of Chemical Structure on the Evolution of Aggregate Structure in Fiber-shaped High Density Polyethylene Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1557-1565,I0013页

作者： Bing wang Yuan-Chu Gao Hai wang Hui Niu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China

Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shaped HDPE vitrimers through a reaction extrusion and post-drawing *** chemical structure characterization,morphology observation,thermal and mechanical properties investigation,as well as aggregate structure analysis,this work revealed the influence of dynamic bonds on the formation of aggregate structures during fiber-shaped vitrimers processing.A small amount of dynamic bonds in HDPE restricts the motion of PE chain during melt-extruding and post-drawing,resulting in a lower orientation of the PE ***,lamellar growth and fibril formation during post-drawing at high temperature are enhanced to some extent due to the competition between dynamic bond and chain *** uneven morphology of fibershaped HDPE vitrimers can be attributed to the stronger elastic effect brought by dynamic bonding,which plays a more dominant role in determining the mechanical properties of fiber-shaped vitrimers compared to aggregate *** Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shap

关键词： High density polyethylene vitrimer Fiber-shaped Aggregate structures Transesterification reaction

LncRNA PVT1靶向调控Sg1基因在肾细胞癌侵袭和凋亡的机制研究

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国际泌尿系统杂志 2021年第3期41卷 435-440页

作者：陈乙铭王月山宋华解放军联勤保障部队第960医院泌尿外科

目的探究LncRNA PVT1靶向调控Sg1基因在肾细胞癌侵袭和凋亡的机制,以期为临床上肾癌的治疗提供新的靶点。方法选择2015年12月至2018年12月本院收治的58例肾细胞癌患者为研究对象,术中收集患者的肿瘤组织和癌旁组织。利用GEO数据库中肾... 详细信息

目的探究LncRNA PVT1靶向调控Sg1基因在肾细胞癌侵袭和凋亡的机制,以期为临床上肾癌的治疗提供新的靶点。方法选择2015年12月至2018年12月本院收治的58例肾细胞癌患者为研究对象,术中收集患者的肿瘤组织和癌旁组织。利用GEO数据库中肾癌组织中LncRNAs数据,通过高通量数据分析肾癌组织中LncRNAs的差异性表达,利用实时荧光定量PCR(RT-qPCR)检测肾癌组织中LncRNA PVT1的相对表达量。通过siRNA干扰技术以及基因过表达技术构建LncRNA PVT1的沉默载体和过表达载体,通过慢病毒转染人肾癌细胞系ACHN细胞,根据是否转染慢病毒以及慢病毒载体的类型,将ACHN细胞分成空白对照组、siRNA沉默组和siRNA过表达组。利用RT-qPCR和Western blot法检测Bcl-2、Bad、Bax和Caspase-3的表达水平。利用Transwell试剂盒检测细胞的侵袭,利用AV-PI试剂盒检测细胞的凋亡。以裸鼠为研究对象,进行种植瘤研究。结果肿瘤组织中LncRNA PVT1的表达量明显升高(P<0.05)。RT-qPCR结果显示,siRNA沉默组的LncRNA PVT1、Sg1和促凋亡基因Bad、Bax和Caspase-3的mRNA表达量要明显低于空白对照组和过表达组(P<0.05);siRNA沉默组的抑凋亡基因Bcl-2的mRNA表达量要明显高于空白对照组和过表达组(P<0.05)。Western blot结果显示,siRNA沉默组的LncRNA PVT1、Sg1和促凋亡基因Bad、Bax和Caspase-3的蛋白表达量要明显低于空白对照组和过表达组(P<0.05);siRNA沉默组的抑凋亡基因Bcl-2的蛋白表达量要明显高于空白对照组和过表达组(P<0.05)。Transwell结果显示,siRNA沉默组细胞的侵袭能力要明显高于空白对照组和过表达组(P<0.05);过表达组细胞的侵袭能力要明显低于空白对照组(P<0.05);AV-PI试剂盒检测结果显示,siRNA沉默组细胞的凋亡率要明显低于空白对照组和过表达组(P<0.05);过表达组细胞的凋亡率要明显高于空白对照组(P<0.05)。siRNA沉默组裸鼠移植瘤的直径明显大于空白对照组和过表达组(P<0.05);过表达组裸鼠移植瘤的直径要小于空白对照组和siRNA沉默组(P<0.05)。结论 LncRNA PVT1通过靶向调控Sg1基因调控肾细胞癌的侵袭和凋亡。

关键词：肾肿瘤 RNA Sg1 细胞凋亡