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Study on Dynamic Mechanical Behavior of Al-Mg-Si Alloy

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Journal of Wuhan University of Technology(Materials Science) 2024年第2期39卷 454-462页

作者：陶小旺 liu Jibo liu Xianbin CHEN Jianbin WANG yonggang 汪小锋 Key Laboratory of Impact and Safety Engineering Ministry of EducationNingbo UniversityNingbo 315211China Ningbo Zhanci New Material Co. Ltd.Ningbo 315338China

The dynamic mechanical behavior of Al-Mg-Si alloy was investigated under different strain rates by mechanical property and microstructure characterization,constitutive behavior analysis and numerical simulation in the present *** the strain rate increases,the yield strength,ultimate tensile strength and elongation increase first,then remain almost constant,and finally *** alloy always exhibits a typical ductile fracture mode,not depending on the strain ***,as the strain rate increases,the number of dimples gradually *** deformation can refine grains,however,the grain structure is slightly affected by the strain *** optimized Johnson-Cook constitutive equation was used to describe the mechanical behavior and obtained by fitting the true stress-strain *** parameter C was described by a function related to the strain *** fitting true stress-strain curves by the JC model agree very well with the experimental true stress-strain *** true stress-strain curves calculated by the finite element numerical simulation agree well with the experimental true stress-strain curves.

关键词： Al-Mg-Si alloy strain rate mechanical property microstructure Johnson-Cook model finite element simulation

噻虫嗪棉花种子包衣的残留动态及与棉蚜防效的相关性分析

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甘肃农业大学学报 2024年第1期59卷 178-184,193页

作者：冀钦陇张海英李惠霞陈元辉李广阔刘永刚甘肃农业大学植物保护学院甘肃省生物防治工程实验室甘肃兰州730070 甘肃省农业科学院植物保护研究所甘肃省无公害农药工程实验室甘肃兰州730070 新疆农业科学院植物保护研究所农业部西北荒漠绿洲作物有害生物综合治理重点实验室新疆乌鲁木齐830091

【目的】新烟碱类杀虫剂具有的内吸活性和向顶传导特性,可用做种子处理来防治蚜虫、粉虱等刺吸式口器害虫,探讨噻虫嗪处理种子后农药的残留动态与防效的相关性,为其合理应用提供理论依据。【方法】以棉花为试材,用30%噻虫嗪悬浮种衣剂... 详细信息

【目的】新烟碱类杀虫剂具有的内吸活性和向顶传导特性,可用做种子处理来防治蚜虫、粉虱等刺吸式口器害虫,探讨噻虫嗪处理种子后农药的残留动态与防效的相关性,为其合理应用提供理论依据。【方法】以棉花为试材,用30%噻虫嗪悬浮种衣剂不同剂量进行种子包衣处理,调查防治效果的同时采集棉花植株样品,采用液质联用的方法分析棉花植株中噻虫嗪及其代谢产物噻虫胺在棉花植株中的残留及消解动态。【结果】噻虫嗪棉花种子包衣后,播后16 d首次采样,不同剂量噻虫嗪在棉花植株中的残留量为0.753~2.768 mg/kg,其代谢产物噻虫胺含量范围为0.278~0.894 mg/kg。随着时间的推移,两者残留量呈指数下降,播后66 d对棉花样品进行检测时,2种药物在棉花中的含量均小于检出限0.001 mg/kg,噻虫嗪及代谢产物噻虫胺在棉花中的消解动态均符合一级动力学方程。【结论】不同剂量噻虫嗪种子包衣可显著降低苗期蚜虫虫口密度,表现出明显的剂量效应,并且植株中的农药残留水平与棉蚜防治效果之间有较强的相关性,其作用机理可能与棉蚜刺探叶片后产生拒食效应有关。

关键词：噻虫嗪棉花种子包衣残留动态剂量效应

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灯盏细辛中1个新咖啡酰酯类化合物的分离鉴定及抗肿瘤活性研究

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中草药 2024年第14期55卷 4650-4655页

作者：陈恒王春国饶沁玲黄智兴王钰淼公佳玉李沐轩刘永刚邓欣祺北京中医药大学中药学院北京102488 北京中医药大学北京中医药研究院北京100029 北京中医药大学人文学院北京102488 中国中医科学院中药研究所北京100700

目的研究灯盏细辛Erigeron breviscapus的化学成分及其体外抗胶质母细胞瘤和结肠癌活性。方法采用大孔树脂柱色谱、中压制备色谱、高压制备色谱等多种方法进行分离和纯化,利用1D-NMR、2D-NMR、HR-ESI-MS、UV、IR等波谱技术对分离得到的... 详细信息

目的研究灯盏细辛Erigeron breviscapus的化学成分及其体外抗胶质母细胞瘤和结肠癌活性。方法采用大孔树脂柱色谱、中压制备色谱、高压制备色谱等多种方法进行分离和纯化,利用1D-NMR、2D-NMR、HR-ESI-MS、UV、IR等波谱技术对分离得到的化合物进行结构鉴定,采用CCK-8法对新化合物的活性进行筛选。结果从灯盏细辛80%甲醇提取物中分离得到4个化合物,分别鉴定为反式-4-咖啡酰氧基-3-羟基-6-咖啡酰氧甲基-7,8-二氧杂环[3.2.1]辛烷-1-羧酸(1)、异绿原酸A(2)、绿原酸(3)和新绿原酸(4);其中化合物1对人胶质瘤U87细胞和人结肠癌HT29细胞的半数抑制浓度(half inhibitory concentration,IC_(50))分别为(13.31±0.77)、(14.83±0.92)μmol/L。结论化合物1为新化合物,命名为新飞蓬酯乙;化合物1对肿瘤细胞的增殖具有一定的抑制作用。

关键词：灯盏细辛菊科抗肿瘤活性新飞蓬酯乙绿原酸

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新生儿耳廓畸形筛查及耳模无创矫正疗效评估

中华耳科学杂志 2024年第1期22卷 77-82页

作者：邹起瑞任艳丽郭浩李惠芹彭檀周尚清张媛艳刘永刚淮北市人民医院耳鼻喉科淮北235099 淮北市人民医院产科

目的通过新生儿查体时行外耳廓检查,统计分析新生儿耳廓畸形的发生率、矫正率、并发症发生率,评估耳模无创矫正治疗效果。方法选取2020年1月1日—2021年7月1日淮北市人民医院出生的新生儿3797例(7594耳),其中耳廓畸形患儿616例(851耳),... 详细信息

目的通过新生儿查体时行外耳廓检查,统计分析新生儿耳廓畸形的发生率、矫正率、并发症发生率,评估耳模无创矫正治疗效果。方法选取2020年1月1日—2021年7月1日淮北市人民医院出生的新生儿3797例(7594耳),其中耳廓畸形患儿616例(851耳),将进行治疗的119例(173耳)患儿根据出生时间分为1组(≤7 d)125耳、2组(8~42 d)31耳,3组(>42 d)17耳。对于轻微不需治疗及拒绝治疗的患儿监护人,分别于出生后7、14 d进行电话随访,收集相关数据进行汇总分析。比较3组治疗总有效率、并发症发生率、治疗时间。结果新生儿耳廓畸形发生率为11.21%(851/7594),19.32%(119/616)的新生儿耳廓畸形接受了无创矫正治疗,矫正率为20.33%(173/851),12例(10.08%)患儿在矫正过程中出现湿疹,3耳中途放弃治疗,2耳效果不佳,治疗总有效率为97.11%(168/173)。1组治疗有效率显著高于2组和3组,差异有统计学意义(P<0.01);2组与3组治疗有效率比较,差异无统计学意义(P=0.225)。1组治疗时间短于2组和3组,差异有统计学意义(P<0.01);2组治疗时间短于3组,差异有统计学意义(P<0.01)。1组并发症发生率低于2组和3组,差异有统计学意义(P<0.01);2组并发症发生率低于3组,但差异无统计学意义(P=0.530)。结论新生儿耳廓畸形发生率较高,耳模型无创矫正效果好,在新生儿查体时即可对耳廓畸形做出筛查,在最早期发现患耳、避免漏诊,越早治疗效果越好。

关键词：新生儿耳廓畸形耳模型无创矫正

Rbm8a regulates neurogenesis and reduces Alzheimer's disease-associated pathology in the dentate gyrus of 5×FAD mice

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Neural Regeneration Research 2024年第4期19卷 863-871页

作者： Chenlu Zhu Xiao Ren Chen liu Yawei liu yonggang Wang Department of Neurology Lanzhou University Second Hospital Department of Neurology The First Affiliated Hospital of Nanchang University Department of Neurology Xiaogan City Central Hospital Health Service Department of the Guard Bureau of the General Office of the Central Committee of the Communist Party of China Headache Center Department of NeurologyBeijing Tiantan HospitalCapital Medical University

Alzheimer’s disease is a prevalent and debilitating neurodegenerative condition that profoundly affects a patient’s daily functioning with progressive cognitive decline,which can be partly attributed to impaired hippocampal *** in the hippocampal dentate gyrus is likely to persist throughout life but declines with aging,especially in Alzheimer’s *** evidence indicated that RNA-binding protein 8A(Rbm8a)promotes the proliferation of neural progenitor cells,with lower expression levels observed in Alzheimer’s disease patients compared with healthy *** study investigated the hypothesis that Rbm8a overexpression may enhance neurogenesis by promoting the proliferation of neural progenitor cells to improve memory impairment in Alzheimer’s ***,Rbm8a overexpression was induced in the dentate gyrus of 5×FAD mice to validate this *** Rbm8a levels in the dentate gyrus triggered neurogenesis and abated pathological phenotypes(such as plaque formation,gliosis reaction,and dystrophic neurites),leading to ameliorated memory performance in 5×FAD *** sequencing data further substantiated these findings,showing the enrichment of differentially expressed genes involved in biological processes including neurogenesis,cell proliferation,and amyloid protein *** conclusion,overexpressing Rbm8a in the dentate gyrus of 5×FAD mouse brains improved cognitive function by ameliorating amyloid-beta-associated pathological phenotypes and enhancing neurogenesis.

关键词： Adora2a Alzheimer’s disease astrocyte cAMP signaling pathway dentate gyrus dystrophic neurites microglia neurogenesis plaque Rbm8a

Homoleptic alkynyl-protected Ag_(32 )nanocluster with atomic precision: Probing the ligand effect toward CO_(2) electroreduction and 4-nitrophenol reduction

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Nano Research 2022年第10期15卷 8908-8913页

作者： Leyi Chen Fang Sun Quanli Shen Lubing Qin yonggang liu Liang Qiao Qing Tang Likai Wang Zhenghua Tang New Energy Research Institute School of Environment and EnergySouth China University of TechnologyGuangzhou Higher Education Mega CentreGuangzhou 510006China School of Chemistry and Chemical Engineering Chongqing Key Laboratory of Theoretical and Computational ChemistryChongqing UniversityChongqing 401331China China Petrochemical Research Institute PetroChina Company LimitedBeijing 102206China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049China Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications Jinan UniversityGuangzhou 510632China

We report a superatomic homoleptic alkynyl-protected Ag_(32)L_(24)(L=3,5-bis(trifluoromethylbenzene)acetylide,Ag_(32) for short)nanocluster with atomic precision,which possesses eight free ***_(32) is formed by an Ag17 core with C3 symmetry and the remaining 15 Ag atoms bond to each other and coordinate with the 24 surface *** applied as electrocatalyst for CO_(2) reduction reaction(CO_(2)RR),Ag_(32) exhibited the highest Faradaic efficiency(FE)of CO up to 96.44%at−0.8 V with hydrogen evolution being significantly suppressed in a wide potential range,meanwhile it has a reaction rate constant of 0.242 min−1 at room temperature and an activation energy of 45.21 kJ·mol−1 in catalyzing the reduction of 4-nitrophenol,both markedly superior than the thiolate and phosphine ligand co-protected Ag_(32) *** strong ligand effect was further understood by density functional theory(DFT)calculations,as it revealed that,one single ligand stripping off from the intact cluster can create the undercoordinated Ag atom as the catalytically active site for both clusters,but alkynyl-protected Ag_(32) nanocluster possesses a smaller energy barrier for forming the key*COOH intermediate in CO_(2)RR,and favors the adsorption of *** study not only discovers a new member of homoleptic alkynyl-protected Ag nanocluster,but also highlights the great potentials of employing alkynyl-protected Ag nanoclusters as bifunctional catalysts toward various reactions.

关键词： Ag_(32)nanocluster,alkynyl ligand,ligand effect,CO_(2)electroreduction,4-nitrophenol reduction

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增程式混合动力汽车高速运行经济性研究

客车技术与研究 2024年第3期46卷 6-10页

作者：潘文军周晓刚丁磊刘永刚东风柳州汽车有限公司广西柳州545005 重庆大学高端装备机械传动全国重点实验室重庆400044

为了评估增程式混合动力汽车在高速工况下的燃油经济性,本文建立某MPV的整车动力学模型和关键零部件模型,并提出相应的能量管理策略。试验结果表明,基于所提能量直驱策略的增程式混合动力汽车的高速燃油经济性显著提升,解决了增程式混... 详细信息

为了评估增程式混合动力汽车在高速工况下的燃油经济性,本文建立某MPV的整车动力学模型和关键零部件模型,并提出相应的能量管理策略。试验结果表明,基于所提能量直驱策略的增程式混合动力汽车的高速燃油经济性显著提升,解决了增程式混合动力高速燃油经济性劣于燃油车的行业难题。

关键词：增程式混合动力汽车高速运行经济性

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大理苍山模式标本植物富集的原因探析

西部林业科学 2024年第3期53卷 55-61页

作者：刘永刚贠新华柴勇李甜江冯倩李园园武力焦志伟云南省林业和草原科学院云南昆明650201 苍山洱海国家级自然保护区管理局云南大理671000

大理苍山是中国模式标本植物最为集中地区之一。为厘清苍山模式标本植物富集的原因,基于现有文献和物种信息数字化平台(如CVH、iplant、sp2000),对现有模式标本产自苍山或苍山附近的种子植物名录进行整理,获得目前被广泛接受的模式标本... 详细信息

大理苍山是中国模式标本植物最为集中地区之一。为厘清苍山模式标本植物富集的原因,基于现有文献和物种信息数字化平台(如CVH、iplant、sp2000),对现有模式标本产自苍山或苍山附近的种子植物名录进行整理,获得目前被广泛接受的模式标本植物名录,并分析其特有性;对苍山植物标本采集的时空动态进行分析,探究苍山模式标本植物众多的历史原因。结果显示:(1)目前共记录苍山产模式标本种子植物297种,其中苍山特有种22种。(2)苍山植物标本采集的历史可追溯至1883年。1900-2020年的121年间,有118个年度都在大理发生了植物标本采集事件(频率达97.5%);1905-2017年的113年间,有80个年度都在苍山发生了植物标本采集事件(频率70.8%)。在大理采集量出现峰值的16个年度中,8个年度也有在苍山采集的记录,同步率50%。结果表明:(1)苍山的地理位置独特,位于多个植物区系的交汇地带,自然条件孕育了丰富的生物多样性和特有种群。同时,其紧邻大理古城的地理优势,使其成为滇西、滇西北地区植物探索的重要节点。自1883年以来,国内外植物学家频繁造访苍山,促进了新物种的发现与描述,进而增加了苍山产模式标本植物的种类多样性。(2)植物模式标本产地种群携带有物种形态学、生态学和遗传学等有用的研究信息,对其保护宜以就地保护为好。建议加强对苍山产模式标本植物原产地种群的就地保护措施,以保护这一珍贵的生物多样性资源。

关键词：标本采集模式标本种子植物大理苍山产地种群

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Electromechanical Transient Modeling Analysis of Large-Scale New Energy Grid Connection

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Energy Engineering 2024年第4期121卷 1109-1125页

作者： Shichao Cao yonggang Dong Xiaoying liu Department of Electrical Engineering Hebei Vocational University of Technology and EngineeringXingtai054000China

The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous *** also has the same inertia,damping,frequency,voltage regulation,and other external performance as the *** is the key technology to realize new energy grid connections’stable and reliable *** project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor.A new energy storage method is *** mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power,state of charge,operation efficiency,dead zone,and inverter *** rapid conversion of energy storage devices absorbs the excess instantaneous kinetic energy caused by *** branch transient of the critical cut set in the system can be confined to a limited ***,the virtual synchronizer’s kinetic and potential energy can be efficiently converted into an instantaneous *** simulation of power system analysis software package(PSASP)verifies the correctness of the theory and algorithm in this *** paper provides a theoretical basis for improving the transient stability of new energy-connected power grids.

关键词： New energy grid connection transient electromechanical modeling synchronous virtual machine PSASP software energy storage