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人工淹没空化射流喷丸强化7075铝合金性能分析

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表面技术 2024年第7期53卷 190-199页

作者：吴思豪杨勇飞施卫东王高伟伍祥龙吴锐南通大学机械工程学院江苏南通226019

目的利用喷丸强化技术提高材料的性能,延长零件的使用寿命。方法在人工淹没空化射流喷丸中,利用由2个具有大速度差的同心共流射流产生的剪切层引起的空化,在承受疲劳载荷或腐蚀环境的金属部件的表面层中引入压缩残余应力,从而实现冲击... 详细信息

目的利用喷丸强化技术提高材料的性能,延长零件的使用寿命。方法在人工淹没空化射流喷丸中,利用由2个具有大速度差的同心共流射流产生的剪切层引起的空化,在承受疲劳载荷或腐蚀环境的金属部件的表面层中引入压缩残余应力,从而实现冲击性能显著提高的新型喷丸强化技术。为了进一步验证人工淹没空化射流的强化性能,采用人工淹没空化射流喷丸对7075铝合金(Al7075)进行表面强化处理,研究不同扫描速度的人工淹没空化射流喷丸对其微观组织和力学性能的影响。观测不同扫描速度人工淹没空化射流喷丸下Al7075的表面形貌和粗糙度。结果在扫描速度为3.0mm/min时,粗糙度值约为1.27μm;在扫描速度为2.0 mm/min时,粗糙度值约为4.08μm;在扫描速度为1.0 mm/min时,粗糙度值约为12.35μm。测量了人工淹没空化射流喷丸冲击前后Al7075的残余应力和显微硬度沿深度方向的分布,研究并讨论了Al7075在人工淹没空化射流喷丸过程中的微观结构演变。结论人工淹没空化射流喷丸会在Al7075表面发生塑性变形,增加了表面粗糙度,且产生加工硬化。揭示了Al7075在塑性变形过程中的晶粒细化机制,旨在为获得高性能的Al7075提供一种新的表面强化方法。

关键词：人工淹没空化射流喷丸 7075铝合金显微硬度残余应力微观结构演化表面强化

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深层超深层油气藏高应力下数字岩心构建方法

石油钻探技术 2024年第2期52卷 38-47页

作者：姚军王春起黄朝琴杨永飞孙海张磊中国石油大学(华东)石油工程学院山东青岛266580 中国石油大学(华东)油气渗流研究中心山东青岛266580

深层超深层油气藏由于埋藏深,其地应力达200 MPa,会显著改变储层岩石孔隙的微观结构。数字岩心是孔隙尺度数值模拟的重要载体,但是现有数字岩心重构方法是基于常温常压下岩心的扫描图像重构,不能反映高应力下的孔隙结构。为此,提出了一... 详细信息

深层超深层油气藏由于埋藏深,其地应力达200 MPa,会显著改变储层岩石孔隙的微观结构。数字岩心是孔隙尺度数值模拟的重要载体,但是现有数字岩心重构方法是基于常温常压下岩心的扫描图像重构,不能反映高应力下的孔隙结构。为此,提出了一种基于离散元法考虑高应力影响的数字岩心重构方法。首先,采用分水岭算法分割CT图像,利用球面谐波分析方法建立轮廓数据库,并在PFC^(3D)中建立Clump(团簇)模板库;然后,根据孔隙度和粒径分布使用模板库中的Clump建立离散元模型,并用两点相关和线性路径相关函数曲线评价模型的准确性;随后,标定颗粒间微观力学参数,并加载应力模拟得到不同应力下的数字岩心;最后,分析了不同应力下数字岩心的孔隙几何拓扑结构,计算孔隙度和渗透率。以Bentheim砂岩为例,构建了其不同应力下的数字岩心,研究结果表明,应力增大,导致孔隙和喉道半径缩小、喉道伸长、连通性变差、孔隙度和渗透率减小。研究结果为深层超深层油气藏孔隙尺度模拟提供了技术途径。

关键词：油气藏深层超深层数字岩心重构离散元法孔隙几何拓扑结构渗透率

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斜齿轮疲劳寿命及节点位移修形方法研究

机械传动 2024年第5期48卷 10-15页

作者：李俞峰李冬阳吴鲁纪葛世祥杨永飞常昊郑机所(郑州)传动科技有限公司河南郑州450001

针对齿轮传动系统疲劳寿命分析困难和修形局限性问题,通过Adams动力学仿真得到时域接触力曲线,并作为模拟分析载荷谱;结合有限元静态求解历程及齿轮材料的S-N曲线,在nCode中解析了斜齿轮副疲劳寿命;在应变分析引导的基础上,提出一种节... 详细信息

针对齿轮传动系统疲劳寿命分析困难和修形局限性问题,通过Adams动力学仿真得到时域接触力曲线,并作为模拟分析载荷谱;结合有限元静态求解历程及齿轮材料的S-N曲线,在nCode中解析了斜齿轮副疲劳寿命;在应变分析引导的基础上,提出一种节点位移修形方法,对等分截面节点变形量进行K-Means聚类整合;利用最优象征节点位移的类指基函数拟合方法得到齿廓修正曲线,与轮齿受载产生的变形量高度吻合;相比于传统的直线型修形,疲劳寿命提高16.98%。将齿轮啮合过程中的受力不均载情况通过节点变形反馈,对渐开线齿廓进行有效修正,平衡啮合界面受力分布,延长疲劳寿命。

关键词：动力学载荷谱疲劳寿命节点位移齿廓修正

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智慧绿色矿山建设技术探讨

江苏建材 2024年第1期 118-119页

作者：魏晓华杨永飞邢月龙中国建筑材料工业地质勘查中心江苏总队江苏南京211106

以老虎洞山为例,在绿色矿山建设基础上探索建设智慧矿山关键技术,通过精细化管理,有效利用矿产资源、矿石产量动态控制、安全生产监控和管理,实现矿山生产的可视化、合理化、精细化,监测监控系统的实时化、远程化,数据的高度集成化和智... 详细信息

以老虎洞山为例,在绿色矿山建设基础上探索建设智慧矿山关键技术,通过精细化管理,有效利用矿产资源、矿石产量动态控制、安全生产监控和管理,实现矿山生产的可视化、合理化、精细化,监测监控系统的实时化、远程化,数据的高度集成化和智能化。

关键词：绿色矿山智慧矿山人工智能

Plate tectonics in the Archean:Observations versus interpretations

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Science China Earth Sciences 2024年第1期67卷 1-30页

作者： yongfei ZHENG School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Crust-Mantle Materials and Environment Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

Plate tectonics theory,established in the 1960s,has been successful in explaining many geological phenomena,processes and events that occurred in the ***,the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian *** dealing with the relationship between plate tectonics and continental geology,continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and *** separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology,particularly in explaining the fundamental geological characteristics of Archean *** this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics,it led to the development of alternative tectonic models,often involving vertical movements under a regime of stagnant lid tectonics,including not only endogenous processes such as gravitational sagduction,mantle plumes and heat pipes but also exogenous processes such as bolide *** vertical processes were not unique to the Archean but persisted into the *** result from mantle poloidal convection at different depths,not specific to any particular *** the plate tectonics theory from the traditional kinematic model in the 20th century to a holistic kinematic-dynamic model in the 21st century and systematically examining the vertical transport of matter and energy at plate margins,it is evident that plate tectonics can explain the common geological characteristics of Archean cratons,such as lithological associations,structural patterns and metamorphic *** deciphering the structure and composition of convergent plate margins as well as their dynamics,the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Preca

关键词： Plate tectonics Archean geology Continental origin Crustal reworking Plate interior Plate margin

立体定向微创手术对脑胶质瘤患者神经功能的影响

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癌症进展 2024年第1期22卷 36-39页

作者：杨永飞王彪尹凯王天恩左玉超郑州大学第一附属医院神经外科郑州450000

目的探讨立体定向微创手术对脑胶质瘤患者神经功能的影响。方法将100例脑胶质瘤患者根据治疗方法的不同分为传统组和微创组,每组50例,传统组行传统开颅肿瘤切除术,微创组行立体定向微创手术。比较两组患者的手术指标、临床疗效、神经肽... 详细信息

目的探讨立体定向微创手术对脑胶质瘤患者神经功能的影响。方法将100例脑胶质瘤患者根据治疗方法的不同分为传统组和微创组,每组50例,传统组行传统开颅肿瘤切除术,微创组行立体定向微创手术。比较两组患者的手术指标、临床疗效、神经肽水平、美国国立卫生研究院卒中量表(NIHSS)评分、格拉斯哥昏迷量表(GCS)评分、日常生活能力(ADL)评分以及术后并发症发生情况。结果微创组患者手术时间、住院时间均短于传统组,差异均有统计学意义(P﹤0.05)。微创组患者的总有效率为80.00%,高于传统组患者的62.00%,差异有统计学意义(P﹤0.05)。术后1年,两组患者的精氨酸升压素、β-内啡肽水平均低于本组术前,但微创组患者的精氨酸升压素、β-内啡肽水平均高于传统组,差异均有统计学意义(P﹤0.05)。术后3个月,两组患者的NIHSS评分均低于本组术前,且微创组患者的NIHSS评分低于传统组,两组患者的GCS、ADL评分均高于本组术前,且微创组患者的GCS、ADL评分均高于传统组,差异均有统计学意义(P﹤0.05)。微创组患者的并发症总发生率为8.00%,低于传统组患者的24.00%,差异有统计学意义(P﹤0.05)。结论立体定向微创手术应用于脑胶质瘤患者的治疗中,可缩短手术时间与住院时间,提高临床疗效,减轻对患者神经系统的损伤,改善神经缺损状况,从而有助于提高患者的日常生活能力,降低并发症发生率。

关键词：立体定向微创手术脑胶质瘤神经功能

Computational fluid dynamic-discrete element method coupling analysis of particle transport in branched networks

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Particuology 2021年第2期19卷 140-150页

作者： Xiaoyu Wang Jun Yao Liang Gong yang Li yongfei yang Hongliang Zhao Research Center of Multiphase Flow in Porous Media China University of Petroleum(East China)Qingdao 266580China College of New Energy China University of Petroleum(East China)Qingdao 266580China Department of Oilfield Exploration&Development SinopecBeijing 100029China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

An understanding of the particle transport characteristics in a branched network helps to predict the particle distribution and prevent undesired plugging in various engineering *** analysis of particle flow characteristics is challenging in that experiments are expensive and particle flow is difficult to detect without disturbing the *** overcome this difficulty,man-made fractal tree-like branched networks were built,and a coupled computational fluid dynamic and discrete element method model was applied.A series of numerical simulations was carried out to analyze the influence of fractal structure parameters of networks on the particle flow *** joint influence of inertial,shunt capacity and superposition from upstream branches on particle flow was *** injection position at the inlet determined the particle velocity and its future flow *** particle density ratio,particle size and bifurcation angle had a greater influence on the shunting of K2 branches than that in the K1 level and N_(k22)/N_(k21) reached a maximum at 60°.Compared with a network with an even number of branches,there was a preferential branch when the branch number was *** preferential branch effect or asymmetry degree of the level(K2)branches had a more significant impact on particle shunting than that from the upstream branches(K1).

关键词： Particle-fluid flow CFD-DEM coupling Branched network

Ginkgo biloba extract alleviates fatty liver hemorrhagic syndrome in laying hens via reshaping gut microbiota

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Journal of Animal Science and Biotechnology 2024年第1期15卷 277-294页

作者： Xinyue yang Depeng Li Meihong Zhang Yuqing Feng Xiaolu Jin Dan Liu Yuming Guo yongfei Hu State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China

Background Ginkgo biloba extract(GBE)is evidenced to be effective in the prevention and alleviation of metabolic disorders,including obesity,diabetes and fatty liver ***,the role of GBE in alleviating fatty liver hemorrhagic syndrome(FLHS)in laying hens and the underlying mechanisms remain to be ***,we investigated the effects of GBE on relieving FLHS with an emphasis on the modulatory role of GBE in chicken gut *** The results showed that GBE treatment ameliorated biochemical blood indicators in high-fat diet(HFD)-induced FLHS laying hen model by decreasing the levels of TG,TC,ALT and *** lipid accumulation and pathological score of liver were also relieved after GBE ***,GBE treatment enhanced the antioxidant activity of liver and serum by increasing GSH,SOD,T-AOC,GSH-PX and reducing MDA,and downregulated the expression of genes related to lipid synthesis(FAS,LXRα,GPAT1,PPARγand Ch REBP1)and inflammatory cytokines(TNF-α,IL-6,TLR4 and NF-κB)in the *** profiling analysis revealed that GBE treatment reshaped the HFD-perturbed gut microbiota,particularly elevated the abundance of Megasphaera in the ***,targeted metabolomic analysis of SCFAs revealed that GBE treatment significantly promoted the production of total SCFAs,acetate and propionate,which were positively correlated with the GBE-enriched gut ***,we confirmed that the GBE-altered gut microbiota was sufficient to alleviate FLHS by fecal microbiota transplantation(FMT).Conclusions We provided evidence that GBE alleviated FLHS in HFD-induced laying hens through reshaping the composition of gut *** findings shed light on mechanism underlying the anti-FLHS efficacy of GBE and lay foundations for future use of GBE as additive to prevent and control FLHS in laying hen industry.

关键词： Antioxidation Fecal microbiota transplantation FLHS Ginkgo biloba extract Inflammation Megasphaera

Cancer cachexia:Focus on cachexia factors and inter-organ communication

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Chinese Medical Journal 2024年第1期137卷 44-62页

作者： yongfei Wang Zikai Dong Ziyi An Weilin Jin The First Clinical Medical College of Lanzhou University LanzhouGansu 730000China Institute of Cancer Neuroscience Medical Frontier Innovation Research CenterThe First Hospital of Lanzhou UniversityThe First Clinical Medical College of Lanzhou UniversityLanzhouGansu 730000China

Cancer cachexia is a multi-organ syndrome and closely related to changes in signal communication between organs,which is mediated by cancer cachexia *** cachexia factors,being the general name of inflammatory factors,circulating proteins,metabolites,and microRNA secreted by tumor or host cells,play a role in secretory or other organs and mediate complex signal communication between organs during cancer *** cachexia factors are also a potential target for the diagnosis and *** pathogenesis of cachexia is unclear and no clear effective treatment is ***,the treatment of cancer cachexia from the perspective of the tumor ecosystem rather than from the perspective of a single molecule and a single organ is urgently *** the point of signal communication between organs mediated by cancer cachexia factors,finding a deeper understanding of the pathogenesis,diagnosis,and treatment of cancer cachexia is of great significance to improve the level of diagnosis and *** review begins with cancer cachexia factors released during the interaction between tumor and host cells,and provides a comprehensive summary of the pathogenesis,diagnosis,and treatment for cancer cachexia,along with a particular sight on multi-organ signal communication mediated by cancer cachexia *** summary aims to deepen medical community’s understanding of cancer cachexia and may conduce to the discovery of new diagnostic and therapeutic targets for cancer cachexia.

关键词： Cancer cachexia Cancer cachexia factors Inter-organ communication Tumor ecosystem Tumor microenvironment