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异常高压气藏采气速度与稳产期定量关系——以阿姆河右岸B-P气田为例

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石油学报 2015年第5期36卷 600-605页

作者：史海东王晖郭春秋张宇成友友中国地质大学能源学院北京100083 中国石油勘探开发研究院北京100083 西南石油大学石油与天然气工程学院四川成都610500

针对阿姆河右岸B区中部异常高压气藏生产动态预测难度大的问题,从气藏实际出发,以物质平衡方程和气井产能公式为基础,结合气藏工程分析及数值模拟方法,建立了异常高压气藏稳产期预测模型。通过分析气藏开发过程,研究了地层流体特征参数... 详细信息

针对阿姆河右岸B区中部异常高压气藏生产动态预测难度大的问题,从气藏实际出发,以物质平衡方程和气井产能公式为基础,结合气藏工程分析及数值模拟方法,建立了异常高压气藏稳产期预测模型。通过分析气藏开发过程,研究了地层流体特征参数随气藏压力下降的变化规律,确定了气藏压力特征值,将异常高压气藏的开发过程划分为高压期与常压期两个阶段,并采用分段函数对预测模型进行求解,得出了不同阶段采气速度与稳产期末采出程度的定量关系。实现了不同采气速度情况下气藏稳产期的快速预测。将该方法应用于B-P气藏并与数模结果相互验证,稳产期预测的绝对误差小于2%,满足工程计算精度要求。同时,采用该定量关系也可对异常高压气藏递减期产量进行预测。

关键词：异常高压气藏采气速度稳产期定量关系预测物质平衡方程

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碳酸盐岩气藏应力敏感特征及微观机理

石油勘探与开发 2023年第1期50卷 152-159页

作者：成友友郭春秋陈鹏羽史海东谭成仟程木伟邢玉忠罗翔西安石油大学地球科学与工程学院西安710065 陕西省油气成藏地质学重点实验室西安710065 中国石油勘探开发研究院北京100083 中国石油(土库曼斯坦)阿姆河天然气公司阿什哈巴德744000土库曼斯坦

在模拟原始地层温度、应力条件下开展储集层应力敏感测试,评价碳酸盐岩岩心的应力敏感特征;在毛管压力曲线标定下,引入变分形维数建立了弛豫时间与孔径的转换公式,基于核磁共振定量分析了不同尺度孔喉条件下因应力敏感造成的孔隙体积损... 详细信息

在模拟原始地层温度、应力条件下开展储集层应力敏感测试,评价碳酸盐岩岩心的应力敏感特征;在毛管压力曲线标定下,引入变分形维数建立了弛豫时间与孔径的转换公式,基于核磁共振定量分析了不同尺度孔喉条件下因应力敏感造成的孔隙体积损失,厘清了碳酸盐岩气藏应力敏感的微观机理。研究发现,裂缝会显著改变碳酸盐岩储集层的应力敏感特征,随着初始渗透率的增加,孔隙型储集层的应力敏感系数先减小后增大,裂缝-孔隙型储集层则单调增大;应力敏感造成的孔隙体积损失主要来源于中孔尺度(0.02~0.50μm)孔隙,贡献率超过50%,单条高角度裂缝对应力敏感、不可逆伤害的贡献率分别为9.6%和15.7%;碳酸盐岩气藏应力敏感的微观机理主要为裂缝闭合、孔隙弹性收缩和骨架塑性变形。

关键词：碳酸盐岩气藏应力敏感核磁共振分形维数孔隙结构微观机理

Bilinear magnetoelectric resistance induced by spin Hall effect

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Science China Materials 2025年第2期68卷 687-688页

作者： Ruiyue Chu cheng Song School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

Magnetoresistance(MR)is a fundamental transport phenomenon crucial for reading magnetic *** also plays a key role in understanding how time-reversal symmetry breaking affects electrical *** discoveries of anisotropic MR[1],giant MR[2],tunneling MR[3],and spin Hall magnetoresistance[4]have driven the development of diverse spintronic devices used in data storage,computing,and sensing ***,these MR effects do not scale linearly with the electric field(and thus,electric current).Recently,nonlinear MR,which scales specifically with the electric current(Ic),has been *** magnetic/non-magnetic bilayers,unidirectional spin Hall magnetoresistance(USMR)[5]shows a linear dependence on Ic,with voltage scaling quadratically with the applied electric field,due to interfacial spin-dependent and electron-magnon scattering mechanisms.

关键词： breaking symmetry linearly

Control of Corner Separation for a Linear Compressor Cascade via Bionic Slanting Riblets at the Endwall

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Journal of Thermal Science 2025年第1期34卷 129-144页

作者： ZHANG Peng LI Yonghong cheng Rixin Key Laboratory of Civil Aircraft Airworthiness Technology Civil Aviation University of ChinaTianjin 300300China College of Aeronautical Engineering Civil Aviation University of ChinaTianjin 300300China

A new passive control approach,utilizing bionic slanting riblets,is employed to mitigate the flow close to the blade endwall in a linear cascade,and its effectiveness and mechanism in controlling corner separation are investigated through numerical *** slanting riblets are positioned at the endwall upstream of the cascade channel,and the influence of riblet height,yaw angle and relative position on the control of corner separation is *** findings indicate that the application of slanting riblets can efficiently counteract corner separation across the stable operational ***,the introduction of riblets with a height of merely 0.1 times the boundary layer thickness results in a significant reduction in total pressure loss by up to 14.53%,while simultaneously enhancing the static pressure coefficient by 21.74%.Flow analysis reveals that minute vortices produced within the riblet channels tend to coalesce,forming a potent large-scale vortex near the boundary layer's base *** phenomenon results in reduced additional losses compared to conventional vortex ***,the induced vortex promotes enhanced mixing between the mainstream flow and boundary layer,inhibiting the lateral displacement of low-energy fluids within the endwall boundary ***,this delays the onset of separation vortex formation and eliminates vortex rings in the corner region,ultimately enhancing the aerodynamic efficiency of the cascade.

关键词： corner separation compressor cascade slanting riblets additional losses vortex generator

Theoretical calculation on degradation mechanism of novel copolyesters under CALB enzyme

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Journal of Environmental Sciences 2025年第3期149卷 242-253页

作者： Yuanyang Ren Zhiwen cheng Luwei cheng Yawei Liu Mingyue Li Tao Yuan Zhemin Shen School of Environmental Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Environmental Protection Key Laboratory of Environmental Health Impact Assessment of Emerging Contaminants Shanghai 200240China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

Poly(butylene succinate-co-furandicarboxylate)(PBSF)and poly(butylene adipateco-furandicarboxylate)(PBAF)are novel furandicarboxylic acid-based biodegradable copolyesters with great potential to replace fossil-derived terephthalic acid-based copolyesters such as poly(butylene succinate-co-terephthalate)(PBST)and poly(butylene adipate-co-terephthalate)(PBAT).In this study,quantum chemistry techniques after molecular dynamics simulations are employed to investigate the degradationmechanism of PBSF and PBAF catalyzed by Candida antarctica lipase B(CALB).Computational analysis indicates that the catalytic reaction follows a four-step mechanism resembling the ping-pong bibi mechanism,with the initial two steps being acylation reactions and the subsequent two being hydrolysis ***,the first step of the hydrolysis is identified as the rate-determining ***,by introducing single-point mutations to expand the substrate entrance tunnel,the catalytic distance of the first acylation step ***,energy barrier of the rate-determining step is decreased in the PBSF system by site-directed mutations on key residues increasing hydrophobicity of the enzyme’s active *** study unprecedently show the substrate binding pocket and hydrophobicity of the enzyme’s active site have the potential to be engineered to enhance the degradation of copolyesters catalyzed by CALB.

关键词： Poly(butylene succinate-co-furandicarboxylate) Poly(butylene adipate-co-furandicarboxylate) Candida antarctica lipase B Degradation mechanism Site-directed mutations

The shadow and gamma-ray bursts of a Schwarzschild black hole in asymptotic safety

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Communications in Theoretical Physics 2025年第2期77卷 121-131页

作者： Yuxuan Shi Hongbo cheng Department of Physics East China University of Science and Technology The Shanghai Key Laboratory of Astrophysics

The effects and rules of the dimensionless parameter ξ on neutrino annihilation v+■→e-+e+dominated gamma-ray bursts are analysed and investigated within the context of black holes in asymptotic *** also computationally model photon orbits around black holes,as photons and neutrinos have the same geodesic equations near black *** show that the black hole shadow radius decreases with increasing ξ.Calculations are made to determine the temperature of the accretion disk surrounding the black hole and the ratio ■Newtof energy deposition per unit time and compared to that of the Newtonian *** accretion disk temperature peaks at a higher temperature due to quantum gravity corrections,which increases the probability of neutrino emission from the black *** is interesting to note that larger quantum gravity effects cause the ratio value to significantly *** the neutrinoantineutrino annihilation process,the energy deposition rate is sufficient even while the energy conversion is inhibited because of quantum ***-ray bursts might originate from the corrected annihilation ***,we examine the derivative d■/dr about the star radius *** findings demonstrate that the ratio is lowered by the black hole's quantum *** neutrino pair annihilation grows weaker the more prominent the influence of quantum gravity.

关键词： quantum gravity black hole gamma-ray burst

Mode-switching cooperative defense strategy for the orbit pursuit-evasion-defense game

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Defence Technology(防务技术) 2025年第2期44卷 272-286页

作者： Yongshang Wei Tianxi Liu cheng Wei School of Aerospace Harbin Institute of TechnologyHarbin150000China

This paper presents a mode-switching collaborative defense strategy for spacecraft pursuit-evasiondefense *** these scenarios,the pursuer tries to avoid the defender while capturing the evader,while the evader and defender form an alliance to prevent the pursuer from achieving its ***,the behavioral modes of the pursuer,including attack and avoidance modes,were established using differential game *** modes are then recognized by an interactive multiple model-matching algorithm(IMM),that uses several smooth variable structure filters to match the modes of the pursuer and update their probabilities in real *** on the linear-quadratic optimization theory,combined with the results of strategy identification,a two-way cooperative optimal strategy for the defender and evader is proposed,where the evader aids the defender to intercept the pursuer by performing luring *** results show that the interactive multi-model algorithm based on several smooth variable structure filters perform well in the strategy identification of the pursuer,and the cooperative defense strategy based on strategy identification has good interception performance when facing pursuers,who are able to flexibly adjust their game objectives.

关键词： Cooperative policy Differential games Orbit pursuit-evasion-defense game Mod recognition

On Halmos'third problem on Banach spaces

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Science China Mathematics 2025年第2期68卷 399-420页

作者： Lixin cheng Junsheng Fang Chunlan Jiang School of Mathematical Sciences Xiamen UniversityXiamen 361005China School of Mathematical Sciences Hebei Normal UniversityShijiazhuang 050016China

In 1970,Halmos posed ten open problems in Hilbert *** third problem asks:If an intransitive operator T has an inverse,is its inverse also intransitive?This question is closely related to the invariant subspace *** Enflo's celebrated counterexample on l_(1)provided a negative answer to the invariant subspace problem,the Banach space version of Halmos'third problem has attracted increasing *** this paper,we provide an affirmative answer to this problem under certain spectral *** an application,we show that for an invertible operator T with Dunford's property(C),if T-1is intransitive and there exists a connected componentΩof intσ(T-1)^(^)off the origin and satisfiesΩ∩ρF(T-1)≠φ,then T is also ***,we show that a necessary and sufficient condition for the existence of a bounded linear operator without nontrivial invariant subspaces on the infinite-dimensional space L1(Ω,Σ,μ)(resp.C(K),the space of bounded continuous functions on a complete metric space K)is that(Ω,Σ,μ)isσ-finite(resp.K is compact).

关键词： invariant subspace bounded linear operator Banach space

Three-dimensional fracture of UO_(2)ceramic pellets by phase field modeling

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 165-176页

作者： Wei Xiong Xuan Ye Hongzhang cheng Xiaoming Liu Institute of Nuclear and New Energy Technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Fracture is the primary failure type for the UO_(2)ceramic pellets,which are operated under irradiation and thermal processes,and physically confined by the *** this work,by combining closely coupled physical processes of heat conduction,heat transfer,and mechanical deformation with the cohesive phase field framework,we proposed a high-precision modeling of quasistatic cracking of three-dimensional(3D)UO_(2)ceramic fuel pellets under high temperature and *** simulation results agree well with the experimental results,indicating that the proposed method has the potential to capture 3D crack modes in the interested time ***,we studied the relation of the 3D fracture patterns of fuel pellets with the peak power *** was found that the power level plays a critical role in determining the competition between radial and circumferential cracks,as well as transverse penetrating cracks.

关键词： phase field method nuclear fuel pellet coupled thermo-mechanical model thermal fracture