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The damage to model concrete gravity dams subjected to water explosions

Defence Technology（防务技术） 2023年第9期27卷 119-137页

作者： Shang Ma Ye-qing chen Zhen-qing Wang Shu-tao Li Qing Zhu long-ming chen College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin150001China Institute of Defense Engineering AMSPLABeijing100036China

Over the past century,the safety of dams has gradually attracted attention from all *** on the dynamic response and damage evolution of dams under extreme loads is the basis of dam safety *** recent decades,scholars have studied the responses of dams under earthquake loads,but there is still much room for improvement in experimental and theoretical research on small probability loads such as *** this paper,a 50-m-high concrete gravity dam is used as a prototype dam,and a water explosion model test of a 2.5-m-high concrete gravity dam is *** water pressure and the acceleration response of the dam body in the test are *** pressure characteristics and dynamic response of the dam body are *** the dam damage test as an example,a numerical model of concrete gravity dam damage is established,and the damage evolution of the dam body is *** combining experiments and numerical simulations,the damage characteristics of the dam body under the action of different charge water explosions are *** integrity of the dam body is well maintained under the action of a small-quantity water explosion,and the dynamic response of the dam body is mainly caused by the shock *** the shock wave and the bubble pulsation cause the dam body to accelerate,and the peak acceleration of the dam body under the action of the bubble pulsation is only one percent of the peak acceleration of the dam body under the action of the shock *** subjected to explosions in large quantities of water,the dam body is seriously *** the action of a shock wave,the dam body produces a secondary acceleration response,which is generated by an internal interaction after the dam body is *** damage evolution process of the dam body under the action of a large-scale water explosion is analysed,and it is found that the shock wave pressure of the water explosion causes local damage to the dam body facing the ***

关键词： Underwater explosion Concrete gravity dam Model test Damage evolution

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N-acetylcysteine blocked hypoxia-reoxygenation induced apoptosis through ROS-p38 MAPK signaling pathway in neonatal rat cardiomyocytes

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Journal of Geriatric Cardiology 2009年第3期6卷 168-172页

作者： Feng-Xiang Zhang ming-long chen Bing Yang Ke-Jiang Cao Cardiovascular Medical Center of Jiangsu the First Affiliated Hospital of Nanjing Medical University Nanjing China

Objective Previous investigations have shown that N-acetylcysteine （NAC） could regulate diverse cell type＇s apoptosis. The purpose of this study was to evaluate the mechanism of NAC reversed apoptosis of cardiomyocytes induced by hypoxia-reoxygenation （H/R）. Methods Cardiomyocytes were treated with hypoxia 6 h and reoxygenation 72 h in the absence and presence of NAC （100/2mol/ L）. The ROS was assayed by using Image-iTTM LIVE green reactive oxygen species detection kit. The viability of cell was assayed with trypan blue. Early stages ofapoptosis were assessed by flow cytometry using Annexin V, and late stages of apoptosis were assessed using TUNEL system. Bcl2 and bax mRNA levels were determined by real-time quantitative PCR. Bcl2, bax, p38 and pp38 protein levels were determined by western blot. Results We found that H/R could markedly increase ROS generation and induce the apoptosis of cardiomyocytes （P〈0.01）. NAC （10012 mol/L） significantly reduced the generation of ROS and apoptosis （P all 〈0.01）. NAC also significantly reduced the protein ratio of pp38 and p38 and increased the RNA and protein ratio of bcl2 and bax （P all 〈0.01）. Conclusion The results showed that NAC significantly reduced apoptosis through inhibiting the phosphorylation of p38 signal pathway, which has potential value for clinical cardiac diseases （J Geriatr Cardio12009; 6：168-172）.

关键词： NAC apoptosis hypoxia-reoxygenation ROS p38

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Reverse dedifferentiation of atrial cardiomyocytes after restoration of sinus rhythm from atrial fibrillation in goats

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Journal of Geriatric Cardiology 2009年第4期6卷 230-236页

作者： Feng-Xiang Zhang ming-long chen Bing Yang Wei-Zhu Ju Hong-Wu chen Dong-Jie Xu Chun chen Ke-Jiang Cao Cardiovascular Medical Center of Jiangsu Province First Affiliated Hospital of Nanjing Medical University Nanjing 210029 China.

Objective Chronic atrial fibrillation （AF） results in dedifferentiation of atrial cardiomyocytes that plays an important role in the perpetuation of AF. In this study, we aimed to investigate the changes oftitin and a-smooth muscle actin （α-SMA） after long time of AF reversal. Methods Twenty-four goats were randomized into four groups：（1） sinus rhythm （SR）, （2） 3 months AF （3-too AF）, （3） 3 months SR after 3 months AF （3-mo post AF）, （4） 6 months SR after 3-mo AF （6-mo post AF）, with 6 in each group. By pacing on the anterior bottom of left atria appendage （LAA）, we established a goat model of chronic AF. Atria effective refractory period （AERP） was measured with electrophysiological methods. Ultra-structure was studied with echocardiography, light and electron microscopy. Titin and α-SMA protein expressions were determined by Western blot. Results The animals underwent high rate pacing on LAA for a mean of 42.23± 21.70 days before presenting AF. Electrophysiological analysis revealed that AERP completely resumed in 3-mo post AF goats. Echocardiography displayed that the size of left atrium resumed almost in 6-too post AF goats （P〈 0.01）. Pathological and electron microscopic examination revealed the disorder of myofibrils, augmentation of intercellular space, myolysis, accumulation of glycogen, and numerous bigger mitochondria among atrial cardiomyocytes in 3-mo AF goats. They recovered mostly in 6-mo post AF goats. Western blot showed that the band density oftitin significantly reduced in 3-mo AF goats compared to SR ones [1826 ± 319 vs 5012±854, P 〈 0.01]. In 3- and 6-mo post AF goats, titin increased gradually and it reversed completely in 6-mo post AF goats （3841 ± 601 and 4523 ±833 respectively, P 〈 0.01）. Conversely, the band density ofa-SMAwas significantly higher in 3-mo AF goats （5324 ± 948） than in SR ones （1619 ±271, P 〈 0.01）. In 3- and 6-mo post-AF goats, α-SMA decreased gradually, and it recovered mostly in 6- mo post AF goats （4437 ± 792 and 2205 ±

关键词： cardiology atrial fibrillation reverse remodeling dedifferentiation electrophysiological study

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MoS_(2)Lubricate‑Toughened MXene/ANF Composites for Multifunctional Electromagnetic Interference Shielding

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Nano-Micro Letters 2025年第2期17卷 358-371页

作者： Jiaen Wang Wei ming longfu chen Tianliang Song Moxi Yele Hao Zhang long Yang Gegen Sarula Benliang Liang Luting Yan Guangsheng Wang School of Physical Science and Engineering Beijing Jiaotong UniversityBeijing 100044People’s Republic of China Key Laboratory of Bio‑Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191People’s Republic of China

The design and fabrication of high toughness electromagnetic interference(EMI)shielding composite films with diminished reflection are an imperative task to solve electromagnetic pollution *** MXene/ANF(aramid nanofibers)–MoS_(2)composite films with nacre-like layered structure here are fabricated after the introduction of MoS_(2)into binary MXene/ANF composite *** introduction of MoS_(2)fulfills an impressive“kill three birds with one stone”improvement effect:lubrication toughening mechanical performance,reduction in secondary reflection pollution of electromagnetic wave,and improvement in the performance of photothermal *** the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 50:50),the strain to failure and tensile strength increase from 22.1±1.7%and 105.7±6.4 MPa and to 25.8±0.7%and 167.3±9.1 MPa,*** toughness elevates from 13.0±4.1 to 26.3±0.8 MJ m^(−3)(~102.3%)*** the reflection shielding effectiveness(SE_(R))of MXene/ANF(mass ratio of 50:50)decreases~10.8%.EMI shielding effectiveness(EMI SE)elevates to 41.0 dB(8.2–12.4 GHz);After the introduction of MoS_(2)into binary MXene/ANF(mass ratio of 60:40),the strain to failure increases from 18.3±1.9%to 28.1±0.7%(~53.5%),the SE_(R)decreases~22.2%,and the corresponding EMI SE is 43.9 *** MoS_(2)also leads to a more efficient photothermal conversion performance(~45 to~55℃).Additionally,MXene/ANF–MoS_(2)composite films exhibit excellent electric heating performance,quick temperature elevation(15 s),excellent cycle stability(2,2.5,and 3 V),and long-term stability(2520 s).Combining with excellent mechanical performance with high MXene content,electric heating performance,and photothermal conversion performance,EMI shielding ternary MXene/ANF–MoS_(2)composite films could be applied in many industrial *** work broadens how to achieve a balance between mechanical properties and versatility of composites in the case of high-function fillers.

关键词： MXene-MoS_(2) Lubrication toughening EMI shielding Photothermal conversion Electric heating performance

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常见矿物药近红外漫反射光谱特征归纳与分析

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中国中药杂志 2016年第19期41卷 3528-3536页

作者：陈龙袁明洋陈科力湖北中医药大学教育部中药资源和中药复方重点实验室湖北武汉430065 武汉市中医医院武汉市中医药研究所湖北武汉430014

结合前期研究工作,对51种不同阴离子类型的常见矿物药的近红外漫反射光谱（near infrared diffuse reflectance spectrometry,NIR）特征谱段进行归纳和解析,并参考矿物学和地质学文献,确定矿物类中药NIR特征谱段的归属,为其NIR快速鉴别... 详细信息

结合前期研究工作,对51种不同阴离子类型的常见矿物药的近红外漫反射光谱（near infrared diffuse reflectance spectrometry,NIR）特征谱段进行归纳和解析,并参考矿物学和地质学文献,确定矿物类中药NIR特征谱段的归属,为其NIR快速鉴别提供理论依据。结果表明,矿物药的NIR特征主要在8 000~4 000 cm^-1,归属于矿物药中所含的水、羟基（-OH）及碳酸根[CO2-3]等基团。水峰具有一定的规律性：一般结构水与-OH基团在7 000 cm^-1附近有组合峰,尖锐而强,结晶水在7 000,5 100 cm^-1附近有2个强峰,吸附水只在5 100 cm^-1附近有宽峰。不同类型矿物药中水的存在形式不同,含量不同,水峰特征不同,据此可用于矿物药的鉴别。硫酸盐类矿物药多含结晶水,硅酸盐类多含结构水,而碳酸盐类中以吸附水为主,因此,以阴离子类型对矿物药进行分类在NIR分析中具有合理性。此外,由于某些矿物药所含的阳离子类型、杂质种类以及结晶性和晶型存在差异,在4 600~4 000 cm^-1谱段存在专属性的NIR特征,主要可归属于Al-OH,Mg-OH,Fe-OH,Si-OH,[CO2-3]等基团的特征吸收。煅制过的矿物药常伴随水分和主要成分的改变,其NIR特征亦发生变化,可用于其炮制过程的监测。该文对NIR技术在矿物药分析中的适用性和局限性进行讨论：绝大部分矿物药具有明显的NIR特征谱段,可用NIR作为系统分析的主要方法,少数矿物药的NIR特征峰不明显,如紫石英、朱砂、雄黄等,可尝试应用拉曼光谱进行补充。这将为矿物药质量控制提供参考。

关键词：近红外漫反射光谱矿物药特征谱段快速鉴别

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4Cr16Mo模具钢立铣加工过程中的切削力系数

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上海交通大学学报 2009年第1期43卷 25-29页

作者：刘敏景璐璐安庆龙陈明上海交通大学机械与动力工程学院上海200240

在动态铣削力模型基础上,通过正交铣削实验分析了立铣4Cr16Mo模具钢时各加工参数对切向切削力系数Kt和径向切削力系数Kr的影响规律,以及切削参数的优化选择;采用二次多项式模型和偏最小二乘法对其进行回归分析.结果表明:对于Kt,径向切... 详细信息

在动态铣削力模型基础上,通过正交铣削实验分析了立铣4Cr16Mo模具钢时各加工参数对切向切削力系数Kt和径向切削力系数Kr的影响规律,以及切削参数的优化选择;采用二次多项式模型和偏最小二乘法对其进行回归分析.结果表明:对于Kt,径向切深对其影响最大,切削速度次之,每齿进给量的影响最小;而对于Kr,每齿进给量对其影响最大,径向切深次之,切削速度的影响很小.基于此,提出了减小切削力的简单有效办法,同时采用实验方法加以验证.

关键词：模具钢切削力系数偏最小二乘法正交实验

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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 DepartmentofCardiology FirstAffiliatedHospitalofNanjingMedicalUniversityNanjing210029China

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

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回火工艺对W6Mo5Cr4V2钢冷冲模组织和使用寿命的影响

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金属热处理 2003年第2期28卷 59-62页

作者：龙晋明陈庆华昆明理工大学材料与冶金工程学院昆明650093

在低温淬火条件下 ,比较了常规高温回火 (三次 )、中温回火 (一次 ) +高温回火 (二次 )以及低温回火 (二次 )等 3种不同回火工艺对W 6Mo5Cr4V2高速钢冷冲模的组织和性能的影响。结果表明 ,低温回火为最佳工艺 ,此时钢的硬度虽然偏低 (约... 详细信息

在低温淬火条件下 ,比较了常规高温回火 (三次 )、中温回火 (一次 ) +高温回火 (二次 )以及低温回火 (二次 )等 3种不同回火工艺对W 6Mo5Cr4V2高速钢冷冲模的组织和性能的影响。结果表明 ,低温回火为最佳工艺 ,此时钢的硬度虽然偏低 (约 6 1HRC) ,但冷冲模在对弹簧钢板冲孔时的使用寿命却最长。X射线衍射分析发现 ,低温回火后的W 6Mo5Cr4V2高速钢中含有较多残留奥氏体 (约 15 8% ) ,它们在一定程度上可提高钢的韧性 ,阻碍冲击载荷下裂纹的形核与扩展。这是低温回火的W

关键词：组织使用寿命高速钢冷冲模热处理回火残留奥氏体

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Unleashing the Potential of Electroactive Hybrid Biomaterials and Self‑Powered Systems for Bone Therapeutics

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Nano-Micro Letters 2025年第2期17卷 463-497页

作者： Shichang Liu Farid Manshaii Jinmiao chen Xinfei Wang Shaolei Wang Junyi Yin ming Yang Xuxu chen Xinhua Yin Yunlei Zhou Honghui Hospital Xi’an Jiaotong UniversityXi’an 710018People’s Republic of China Department of Bioengineering Henry Samueli School of Engineering and Applied ScienceUniversity of California Los AngelesLos Angeles 90095USA Hangzhou Institute of Technology Xidian UniversityHangzhou 311231People’s Republic of China

The incidence of large bone defects caused by traumatic injury is increasing worldwide,and the tissue regeneration process requires a long recovery time due to limited self-healing *** bioelectrical phenomena have been well recognized as critical biophysical factors in bone remodeling and *** by bioelectricity,electrical stimulation has been widely considered an external intervention to induce the osteogenic lineage of cells and enhance the synthesis of the extracellular matrix,thereby accelerating bone *** ongoing advances in biomaterials and energy-harvesting techniques,electroactive biomaterials and self-powered systems have been considered biomimetic approaches to ensure functional recovery by recapitulating the natural electrophysiological microenvironment of healthy bone *** this review,we first introduce the role of bioelectricity and the endogenous electric field in bone tissue and summarize different techniques to electrically stimulate cells and ***,we highlight the latest progress in exploring electroactive hybrid biomaterials as well as self-powered systems such as triboelectric and piezoelectric-based nanogenerators and photovoltaic cell-based devices and their implementation in bone tissue ***,we emphasize the significance of simulating the target tissue’s electrophysiological microenvironment and propose the opportunities and challenges faced by electroactive hybrid biomaterials and self-powered bioelectronics for bone repair strategies.

关键词： Electroactive biomaterials Self-powered bioelectronics Bone regeneration Bone tissue

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Glutamatergic CYLD deletion leads to aberrant excitatory activity in the basolateral amygdala:association with enhanced cued fear expression

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Neural Regeneration Research 2025年第11期20卷 3259-3272页

作者： Huidong Li Faqin Li Zhaoyi chen Erwen Wu Xiaoxi Dai Danni Li Haojie An Shiyi Zeng Chunyan Wang Li Yang cheng long School of Life Sciences South China Normal UniversityGuangzhouGuangdong ProvinceChina School of Life Sciences Guangzhou UniversityGuangzhouGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Major Obstetric Diseases The Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina South China Normal University-Panyu Central Hospital Joint Laboratory of Translational Medical Research Panyu Central HospitalGuangzhouGuangdong ProvinceChina

Neuronal activity,synaptic transmission,and molecular changes in the basolateral amygdala play critical roles in fear ***(CYLD)is a deubiquitinase that negatively regulates the nuclear factor kappa-B *** is well studied in non-neuronal cells,yet underinvestigated in the brain,where it is highly *** studies have shown involvement of CYLD in the remodeling of glutamatergic synapses,neuroinflammation,fear memory,and anxiety-and autism-like ***,the precise role of CYLD in glutamatergic neurons is largely ***,we first proposed involvement of CYLD in cued fear *** next constructed transgenic model mice with specific deletion of Cyld from glutamatergic *** results show that glutamatergic CYLD deficiency exaggerated the expression of cued fear in only male ***,loss of CYLD in glutamatergic neurons resulted in enhanced neuronal activation,impaired excitatory synaptic transmission,and altered levels of glutamate receptors accompanied by over-activation of microglia in the basolateral amygdala of male ***,our study suggests a critical role of glutamatergic CYLD in maintaining normal neuronal,synaptic,and microglial *** may contribute,at least in part,to cued fear expression.

关键词： basolateral amygdala cued fear expression cylindromatosis deubiquitinase glutamate receptor 1 glutamatergic neuron microglial activation N-methyl-D-aspartate receptor 1 neuronal activation synaptic transmission

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