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Polarization of plane wave propagating inside elastic hexagonal system solids

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Science China(Physics,Mechanics & Astronomy) 2014年第2期57卷 251-262页

作者： FA Lin ZHAO MeiShan LIU YongChang WANG Lei WANG YanQiang sun jigang School of Electronics and Information Engineering Xi'an University of Posts and Telecommunications James Franck Institute and Department of Chemistry University of Chicago5735 South Ellis AvenueChicagoIL 60637USA

Based on the reported physical parameters for hexagonal system solids,we have calculated the effects of anisotropy on polarization of plane P-wave *** we report the results of calculations and the newly observed physical *** is found that,for a given propagation,if the polarization is parallel to the wave vector,so also to the Poynting *** such a case,the phase velocity is identical to the energy velocity;the quasi P-wave degenerates to a pure P-wave along the *** is also noted that if the polarization is parallel to the Poynting vector but not to the wave vector,the propagating wave cannot be a pure ***,the polarization in a quasi P-wave may deviate from the wave vector for more than 45°,but the deviation from the Poynting vector is always less than 45°.The energy velocity of a quasi SV-wave can be larger than that of the quasi P-wave in some propagation directions,even though the phase velocity of a quasi SV-wave may never be larger than either the phase velocity or energy velocity of the quasi ***,in case of parameters ε=0 and δ*≠0,the polarization of a quasi P-wave has an observed symmetry at a 45°phase *** anisotropy of a hexagonal system solid determines if a pure P-wave can be created and what the propagation direction is for a plane wave propagating inside such a hexagonal system solid.

关键词： anisotropy polarization pure P-wave VTI medium hexagonal crystal

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预制缺陷球轴承剥落研究

润滑与密封 2024年第4期49卷 182-188页

作者：杨景来佟文伟刘宇佳孙继刚刘东旭田如钢中国航发沈阳发动机研究所辽宁沈阳110015 中国航空发动机集团航空发动机动力传输重点实验室辽宁沈阳110015

为研究航空发动机球轴承的剥落规律,在4套球轴承外圈滚道表面预制不同数量和分布形式的压坑,模拟轴承实际剥落过程形成的麻坑或剥落坑,利用轴承试验器开展预制缺陷球轴承剥落试验。综合利用润滑油光谱分析、自动磨粒分析及铁谱分析方法... 详细信息

为研究航空发动机球轴承的剥落规律,在4套球轴承外圈滚道表面预制不同数量和分布形式的压坑,模拟轴承实际剥落过程形成的麻坑或剥落坑,利用轴承试验器开展预制缺陷球轴承剥落试验。综合利用润滑油光谱分析、自动磨粒分析及铁谱分析方法对轴承试验润滑油中磨粒进行分析。结果表明:轴承剥落时产生的磨粒以疲劳磨粒为主,严重滑动磨粒和切削磨粒为辅,同时存在磨粒氧化现象;轴承剥落产生的球形磨粒主要在5μm以下,少量分布在6~10μm,个别在10μm以上;轴承剥落过程中,磨粒总量和大尺寸磨粒数量出现明显增长。航空发动机球轴承的剥落机制为:预制凹坑边缘首先产生疲劳裂纹,然后因预制凹坑后方的一段区域内难以形成动压润滑,在交变接触应力作用下,外圈滚道表面或次表面出现疲劳裂纹,形成剥落区;滚道剥落区沿周向不断朝两侧扩展,并逐渐将预制凹坑区域覆盖,形成长条形的大面积剥落带,直至轴承最终失效。

关键词：航空发动机球轴承剥落试验磨粒故障监测

Enhanced bifunctional oxygen electrochemical catalytic performance using La-doped CoFe_(2)O_(4)spinel supported by 3D-G for Zn-air batteries

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Journal of Energy Chemistry 2024年第7期94卷 778-788页

作者： Yinggang sun Tingwei Zhang Peng sun jigang Wang Wenjie Duan Yanqiong Zhuang Likai Wang Zhongfang Li School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255049ShandongChina

The preparation of bifunctional catalysts for oxygen reduction(ORR)and oxygen evolution(OER)is crucial for Zn-air ***,we report a La doped CoFe_(2)O_(4) spinel catalyst supported on threedimensional graphene(3D-G),where La can facilitate electron transfer from Co to Fe,leading to increased electron cloud density in Fe and improved catalytic *** redshift of the G peak in the Raman spectra indicates the interaction between theπbond of 3D-G and d orbitals in La_(0.2)CoFe_(1.8)O_(4).La_(0.2)CoFe_(1.8)/3D-G exhibits superior ORR performance(E_(1/2)=0.86 V ***)and OER performance(E_(j=10)=1.55 V ***)to CoFe_(2)O_(4)/3D-G(E_(1/2)=0.831 V ***,E_(j=10)=1.603 V ***).Furthermore,it demonstrates excellent bifunctional oxygen catalytic performance while maintaining high power density and stability in liquid zinc-air batteries(ZABs)and flexible ZABs(F-ZABs).This work presents a viable strategy for utilizing rare earth element doped spinels to enhance oxygen catalyst and ZABs performance.

关键词： Zn-air batteries Electrocatalysts La_(0.2)CoFe_(1.8)/3D-G Electron pump Bifunctional oxygen catalytic performance

Distributed Malware Detection based on Binary File Features in Cloud Computing Environment

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Distributed Malware Detection based on Binary File Features ...

松辽盆地北部断裂演化序列与反转构造带形成机制

第26届中国控制与决策会议

作者： Xiaoguang Han jigang sun Wu Qu Xuanxia Yao School of Computer & Communication Engineering University of Science & Technology Beijing

A number of techniques have been devised by researchers to counter malware attacks, and machine learning techniques play an important role in automated malware detection. Several machine learning approaches have been applied to malware detection, based on different features derived from dynamic analysis of the malware. While these methods demonstrate promise, they pose at least two major challenges. First, these approaches are subjected to a growing array of countermeasures that increase the cost of capturing these malware binary executable file features. Further, feature extraction requires a time investment per binary file that does not scale well to the daily volume of malware instances being reported by those who diligently collect malware. In order to address the first challenge, this article proposed a binary-to-image projection algorithm based on a new type of feature extraction for the malware, was introduced in [2]. To address the second challenge, the technique’s scalability is demonstrated through an implementation for the distributed（Key, Value） abstraction in cloud computing environment. Both theoretical and empirical evidence demonstrate its effectiveness over other state-of-the-art malware detection techniques on malware corpus, and the proposed method could be a useful and efficient complement to dynamic analysis.

关键词： Data Mining Malware Detection Malware Images Distributed Entropy LSH

来源： cnki会议评论

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cnki会议

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石油勘探与开发 2013年第3期40卷 275-283页

作者：孙永河陈艺博孙继刚付晓飞胡明东北石油大学地球科学学院大庆油田有限责任公司第四采油厂地质大队

立足松辽盆地北部区域地震解释,从分析断裂几何学特征着手,以断裂形成演化过程为主线,系统剖析了盆地演化不同阶段断裂的变形机制,揭示了反转构造带的形成机制及其对油气运聚成藏的指示作用。研究表明,松辽盆地北部断裂演化经历了断陷... 详细信息

立足松辽盆地北部区域地震解释,从分析断裂几何学特征着手,以断裂形成演化过程为主线,系统剖析了盆地演化不同阶段断裂的变形机制,揭示了反转构造带的形成机制及其对油气运聚成藏的指示作用。研究表明,松辽盆地北部断裂演化经历了断陷期的持续伸展变形、拗陷期的持续张扭变形和反转期的连续挤压构造反转变形。盆地晚期构造反转变形是在基底深大断裂、断陷期北西—南东向引张应力场形成的半地堑以及拗陷期近东西向拉张应力场形成的多方位断裂密集带基础上开始演化的。反转期左旋压扭变形场与断陷半地堑、基底深大断裂共同控制了次级背斜带和反转构造带的形成,大庆长垣地区受北北东向断陷半地堑和北北东向基底深大断裂双重影响,反转程度最大,将反转期初始北东向的次级背斜带最终连成北北东向的反转构造带,同时将拗陷期形成的以近南北向为主体的断裂密集带旋转改造成以北西—北北西向为主体的断裂密集带展布格局。

关键词：断裂演化断陷构造格局断裂密集带反转构造带形成机制松辽盆地北部

Bioorthogonal microglia-inspired mesenchymal stem cell bioengineering system creates livable niches for enhancing ischemic stroke recovery via the hormesis

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1412-1427页

作者： Jianpei Xu Yinzhe sun Yang You Yuwen Zhang Dan Huang Songlei Zhou Yipu Liu Shiqiang Tong Fenfen Ma Qingxiang Song Chengxiang Dai Suke Li jigang Lei Zhihua Wang Xiaoling Gao Jun Chen Shanghai Pudong Hospital&Department of Pharmaceutics School of PharmacyFudan UniversityShanghai 201203China Key Laboratory of Smart Drug Delivery Ministry of EducationSchool of PharmacyFudan UniversityShanghai 201203China Department of Pharmacology and Chemical Biology State Key Laboratory of Oncogenes and Related GenesShanghai Universities Collaborative Innovation Center for Translational MedicineShanghai Jiao Tong University School of MedicineShanghai 200025China Department of Emergency Shanghai Pudong HospitalFudan University Pudong Medical CenterShanghai 201399China Institute of Science and Technology for Brain-Inspired Intelligence&Department of Neurology Fudan UniversityShanghai 201203China Department of Rehabilitation Medicine Huashan HospitalFudan UniversityShanghai 201203China Daxing Research Institute University of Science and Technology BeijingBiomedical Industry BaseZhongguancun Science and Technology ParkBeijing 102600China Cellular Biomedicine Group Inc. Shanghai 201210China

Mesenchymal stem cells(MSCs)experience substantial viability issues in the stroke infarct region,limiting their therapeutic efficacy and clinical *** levels of deadly reactive oxygen radicals(ROS)and proinflammatory cytokines(PC)in the infarct milieu kill transplanted MSCs,whereas low levels of beneficial ROS and PC stimulate and improve engrafted MSCs’*** on the intrinsic hormesis effects in cellular biology,we built a microglia-inspired MSC bioengineering system to transform detrimental high-level ROS and PC into vitality enhancers for strengthening MSC *** system is achieved by bioorthogonally arming metabolic glycoengineered MSCs with microglial membrane-coated nanoparticles and an antioxidative extracellular protective *** this system,extracellular ROSscavenging and PC-absorbing layers effectively buffer the deleterious effects and establish a microlivable niche at the level of a single MSC for ***,the infarct’s inanimate milieu is transformed at the tissue level into a new living niche to facilitate *** engineered MSCs achieved viability five times higher than natural MSCs at seven days after transplantation and exhibited a superior therapeutic effect for stroke recovery up to 28 *** vitality-augmented system demonstrates the potential to accelerate the clinical translation of MSC treatment and boost stroke recovery.

关键词： Ischemic stroke Mesenchymal stem cell Cell engineering Hormesis effect Bioorthogonal chemistry Microglia Reactive oxygen spices Proinflammatory cytokines

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新型无钴易磨削超硬高速钢的研究

钢铁研究学报 1989年第S1期1卷 135-139页

作者：孙继刚王世章

本文研究了新型无钴易磨削超硬高速钢G105钢的性能,并对钴对高谴钢的一些性能的影响作了探讨。以代替含钴超硬高速钢为目标,新钢种的设计采用了提高钨当量及合理的钨钼配比以达到最大的二次硬化和热稳定性。经过1220℃淬火和580℃三次回... 详细信息

本文研究了新型无钴易磨削超硬高速钢G105钢的性能,并对钴对高谴钢的一些性能的影响作了探讨。以代替含钴超硬高速钢为目标,新钢种的设计采用了提高钨当量及合理的钨钼配比以达到最大的二次硬化和热稳定性。经过1220℃淬火和580℃三次回火,G105钢的回火硬度达到HRC68.6,600℃,4 ×1 h红硬性达到HRC67.1,与M42钢相比,G105钢的高温硬度和抗弯强度与M42相当,冲击韧性较好,切削性能亦不亚于M42钢。实验结果表明:钴加入高速钢中明显提高回火硬度,并使回火硬化峰温度下降,但钴并不提高高碳钼系高速钢600℃以上的红硬性和高温硬度。

关键词：超硬高速钢高温硬度钼系高速钢二次硬化淬火温度残余奥氏体淬火过程切削性能加热系数油淬

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北京理工大学体育馆双曲金属屋面体系

工业建筑 2007年第10期37卷 21-24,49页

作者：洪宙飞孙继刚黄唯五洲工程设计研究院北京100053 中冶京唐建设有限公司石家庄050000 霍高文建筑系统有限公司北京100000

北京理工大学体育文化综合馆工程的屋面采用新型的双曲金属屋面系统,该屋面系统在防腐性、耐久性、抗风性能、防水、防渗性能、排水性能、防火性能、温度变形处理、防雷措施、保温性能、吸声与隔音性能和减振措施等方面较以前的金属屋... 详细信息

北京理工大学体育文化综合馆工程的屋面采用新型的双曲金属屋面系统,该屋面系统在防腐性、耐久性、抗风性能、防水、防渗性能、排水性能、防火性能、温度变形处理、防雷措施、保温性能、吸声与隔音性能和减振措施等方面较以前的金属屋面有很大的提高,从而确保了本工程金属屋面体系的质量。

关键词：北京理工大学体育馆金属屋面直立锁边固定方式

可持续发展理念下投资者-国家争端解决机制的革新

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法治社会 2021年第1期 88-97页

作者：孙继刚中南财经政法大学法学院

可持续发展已经成为国际社会共同遵循的价值目标。投资者-国家争端解决机制在发展过程中,逐渐暴露出在可持续发展理念三大核心原则——公平性、协调性和持续性上的不足。投资者-国家争端解决机制与可持续发展理念的冲突,是其属性和外部... 详细信息

可持续发展已经成为国际社会共同遵循的价值目标。投资者-国家争端解决机制在发展过程中,逐渐暴露出在可持续发展理念三大核心原则——公平性、协调性和持续性上的不足。投资者-国家争端解决机制与可持续发展理念的冲突,是其属性和外部环境共同作用的结果。为了推动投资者-国家争端解决机制走向更加具有可持续性的道路,未来应当着力探索突破“仲裁”性质的束缚,主动利用国际投资协定完善相关内部制度,并鼓励国际社会在该机制改革上共同参与和统一协调,进而推动投资者-国家争端解决机制朝向更加符合可持续发展理念的道路前行。

关键词：可持续发展投资者-国家争端解决机制公平性协调性持续性