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When null energy condition meets ADM mass

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Communications in Theoretical Physics 2022年第9期74卷 145-149页

作者： run-Qiu Yang li li Rong-Gen Cai Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityYaguan Road 135Jinnan DistrictTianjin 300350China CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China

We give a conjecture on the lower bound of the ADM mass M by using the null energy *** conjecture includes a Penrose-like inequality 3M≥_(k)A/(4π)+√A/4πand the Penrose inequality 2M≥√A/4πwith A the event horizon area andκthe surface *** the conjecture in the static spherically symmetric case and the Penrose inequality for a dynamical spacetime with spherical symmetry are proved by imposing the null energy *** then generalize the conjecture to a general dynamical *** results raise a new challenge for the famous unsettled question in general relativity:in what general case can the null energy condition replace other energy conditions to ensure the Penrose inequality?

关键词： Penrose inequality black holes ADM mass energy conditions

The linkage between two ENSO types/modes and the interdecadal changes of ENSO around the year 2000

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Atmospheric and Oceanic Science Letters 2017年第2期10卷 168-174页

作者： WANG run REN Hong-li Chinese Academy of Meteorological Sciences Beijing China Laboratory for Climate Studies & CMA-NJU Joint Laboratory for Climate Prediction Studies National Climate Center China Meteorological Administration Beijing China

This study focuses on the interdecadal changes in ENSO properties emerging around the year 2000. Compared to 1980-1999, after 2000, the ENSO amplitude weakened, the occurrence of the central Pacific （CP） Et Nino increased, and the eastern Pacific （EP） El Nino became suppressed. Meanwhile, the dominant period of ENSO shortened from quasi-quadrennial （QQ） to quasi-biennial （QB）. The authors show that these changes in ENSO properties are evidently consistent with the change in the stability of the ENSO mode through connecting the two ENSO types with the two coupled ENSO modes, i.e. the QQ and QB modes. It is suggested that the relative activity or stability of the two ENSO modes changed after the year 2000. The intensity of both the QQ and QB mode weakened. The QQ mode, which is linked to EP ENSO and was significantly strong during 1980-1999, became much weaker after 2000 in terms of the EP type almost disappearing. Compared with the weakness of the QQ mode, the QB mode, as manifested by the CP type, remained active and became dominant in the tropical Pacific after 2000. Analysis shows that the changes in mean states in the tropical Pacific were likely responsible for the interdecadal ENSO changes around the year 2000.

关键词： Interdecadal change eastern Pacific ENSO central Pacific ENSO quasi-quadrennial mode quasi-biennial mode

Resistive switching effects in oxide sandwiched structures

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Frontiers of Materials Science 2012年第3期6卷 183-206页

作者： Xiao-Jian ZHU Jie SHANG run-Wei li Key Laboratory of Magnetic Materials and Devices Ningbo Institute of Materials Technology and Engineering(NIMTE)Chinese Academy of Sciences(CAS)Ningbo 315201China Zhejiang Province Key Laboratory of Magnetic Materials and Appiication Technology Ningbo Institute of Materials Technology and Engineering(NIMTE)Chinese Academy of Sciences(CAS)Ningbo 315201China

Resistive switching （RS） behaviors have attracted great interest due to their promising potential for the data storage. Among various materials, oxide-based devices appear to be more advantageous considering their handy fabrication and compatibility with CMOS technology, though the underlying mechanism is still controversial due to the diversity of RS behaviors. In this review, we focus on the oxide-based RS memories, in which the working mechanism can be understood basically according to a so-called filament model. The filaments formation/rupture processes, approaches developed to detect and characterize filaments, several effective attempts to improve the performances of RS and the quantum conductance behaviors in oxide-based resistive random access memory （RRAM） devices are addressed, respectively.

关键词： resistive random access memory (RRAM) resistive switching (RS) oxidefilm filaments quantum conductance

Development of Flake Powder Metallurgy in Fabricating Metal Matrix Composites:A Review

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 806-815页

作者： Genlian Fan run Xu Zhanqiu Tan Di Zhang Zhiqiang li State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University

Powder metallurgy （PM） is one of the most applied processes in the fabrication of metal matrix composites （MMCs）. Recently, a novel PM strategy called flake PM was developed to fabricate MMCs with nano-laminated or hierarchical architectures. The name ＂flake PM＂ was derived from the use of flake metal powders, which could benefit the uniform dispersion of reinforcements in the metal matrices and thus result in balanced strength and ductility. Flake PM has been proved to be successful in the dispersion of nano aluminum oxides, carbon nanotubes, graphene nano-sheets, and microsized B4C particles in aluminum or copper matrix. This paper reviews the technique and mechanism developments of flake PM in previous studies, and foresees the future develop of this new fabricating method.

关键词： Metal matrix composites Flake powder metallurgy Micro- and nano-composites Architectures Strength and ductility

Overexpression of Csk-binding protein decreases growth,invasion,and migration of esophageal carcinoma cells by controlling Src activation

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World Journal of Gastroenterology 2015年第6期21卷 1814-1820页

作者： Dong Zhou Peng Dong Yu-Min li Fa-Cai Guo An-Ping Zhang run-ze Song Ya-Min Zhang Zhi-Yong li Dong Yuan Chuan Yang Gansu Provincial Key Laboratory of Digestive System Tumors Lanzhou University Second Hospital Department of Cardiology Aviation General Hospital Department of Vascular Surgery Lanzhou University Second Hospital

AIM:To investigate the mechanisms by which Cskbinding protein(CBP)inhibits tumor progression in esophageal ***:A CBP overexpressing esophageal carcinoma cell line(TE-1)was *** growth,invasion,and migration of CBP-TE-1 cells,as well as the expression of Src were then determined and compared with those in normal TE-1 ***:The expression of Src was decreased by the overexpression of CBP in TE-1 *** growth,invasion,and migration of TE-1 cells were decreased by the overexpression of ***:This study indicates that CBP may decrease the metastasis of esophageal carcinoma by inhibiting the activation of *** may be a potential tumor suppressor and targeting the CBP gene may be an alternative strategy for the development of therapies for esophageal carcinoma.

关键词： Csk-binding protein Esophageal carcinoma Cell grow

Upper Bound Solution of the Resisting Moment Bearing Capacity of A Composite Bucket Shallow Foundation of An Offshore Wind Turbine in Sand

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China Ocean Engineering 2022年第6期36卷 859-870页

作者： liU run li Tian-liang CHEN Guang-si liAN Ji-jian State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

Bearing the large moment that is generated by the wind load that acts on the upper structure of offshore wind turbines is an important feature of their foundations that is different from other offshore structures.A composite bucket shallow foundation(CBSF)has been proposed by Tianjin University to address the soft geological conditions in the offshore regions of China for wind *** CBSF is a new type of foundation and is effective against large *** soil deformation test of a CBSF and the numerical simulation study under the same working conditions are carried out to determine the failure mechanism of a CBSF under moment *** resisting soil compression rateηm is defined as a new empirical parameter that indicates the ability of the soil inside the bucket to resist moment *** upper limit of the resisting moment bearing capacity of the bucket foundation is derived through the upper bound theorem of classical plasticity theory based on the failure *** calculation method is validated by tests of bucket models with different height-diameter ratios in sand under moment loading.

关键词： bucket foundation failure mechanism resisting moment bearing capacity upper bound theorem resisting soil compression rate

Stress, Roughness and Reflectivity Properties of Sputter-Deposited B4C Coatings for X-Ray Mirrors

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Chinese Physics Letters 2019年第12期36卷 17-21页

作者： Jia-li Wu run-ze Qi Qiu-Shi Huang Yu-Fei Feng Zhan-Shan Wang Zi-Hua Xin Department of Physics Shanghai UniversityShanghai 200444 MOE Key Laboratory of Advanced Micro-Structured Materials Shanghai 200092 Institute of Precision Optical Engineering School of Physics Science and EngineeringTongji UniversityShanghai 200092

Boron carbide(B4C)coatings have high reflectivity and are widely used as mirrors for free-electron lasers in the x-ray ***,B4C coatings fabricated by direct-current magnetron sputtering show a strong compressive stress of about-3 *** changing the argon gas pressure and nitrogen-argon gas mixing ratio,we are able to reduce the intrinsic stress to less than-1 GPa for a 50-nm-thick B4C *** is found that the stress in a coating deposited at 10 m Torr is-0.69 GPa,the rms roughness of the coating surface is 0.53 nm,and the coating reflectivity is 88%,which is lower than those of coatings produced at lower working *** the working gas contains 8%nitrogen and 92%argon,the B4 C coating shows not only-1.19 GPa stress but also a low rms roughness of 0.16 nm,and the measured reflectivity is 93%at the wavelength of 0.154 nm.

关键词： coating stress carbide

On the Red Edge of the δ Scuti Instability Strip

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Chinese Journal of Astronomy and Astrophysics 2002年第5期2卷 441-448页

作者： Yan Xu Zhi-Ping li li-Cai Deng Da-run Xiong National Astronomical Observatories Chinese Academy of SciencesBeijing 100012 Department of Physics Tianjin Normal UniversityTianjin 300073 Purple Mountain Observatory Chinese Academy of SciencesNanjing 210008

The δ Scuti star catalogue is used to derive the observational locations of such stars on the HR diagram. The theoretical and observational instability strips are compared to check the theoretical red edge obtained by considering nonlocal time-dependent convection theory. The observational instability strip almost overlaps with the theoretical one, but the observed blue and red envelopes are hotter than the theoretical edges. The distribution of δ Scuti stars in the pulsation strip is not uniform.

关键词： stars: variables: δ Sct - stars: oscillations ?stars: HR diagram

A new neuroprotective bakkenolide from the rhizome of Petasites tricholobus

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Chinese Chemical Letters 2008年第7期19卷 841-844页

作者： Na Zhang Mei li Guo Ge Zhang run Ping li Department of Pharmacognosy School of Pharmacy Second Military Medical University Shanghai 200433 China Department of Diving Medicine Faculty of Naval Medicine Second Military Medical University Shanghai 200433 China

A new bakkenolide-type compound, bakkenolide-Va（1）, was isolated from the rhizome of Petasites tricholobus. The structure was characterized on the basis of various NMR （1H, 13C, 1H-1H COSY, HMQC, HMBC and NOESY） and mass spectrometry data. The neuroprotective activity of bakkenolide-Va was investigated in primarily cultured neurons treated by hypoxia-ghicose deprivation and various types of oxidative insults.

关键词： Petasites tricholobus Compositae Bakkenofide-Va Neuroprotection