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围岩参数不确定性对地下水封洞库稳定性的影响

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山东大学学报（工学版） 2024年第2期54卷 126-135页

作者：彭振华王者超洪成华李康林李傲中海油石化工程有限公司山东青岛266000 辽宁省深部工程与智能技术重点实验室沈阳110819

为了分析库区围岩条件测量不确定性问题对围岩稳定性分析产生的影响,依托国内某地下水封洞库工程,采用ANSYS/FLAC3D建立洞库的三维数值计算模型,开展洞库稳定性数值模拟。将围岩的位移分布、应力分布和塑性区分布作为稳定性的评价指标,... 详细信息

为了分析库区围岩条件测量不确定性问题对围岩稳定性分析产生的影响,依托国内某地下水封洞库工程,采用ANSYS/FLAC3D建立洞库的三维数值计算模型,开展洞库稳定性数值模拟。将围岩的位移分布、应力分布和塑性区分布作为稳定性的评价指标,分析围岩物理力学参数(包括弹性模量、泊松比、密度、内摩擦角、黏聚力和抗拉强度)、地应力方向对洞库围岩稳定性的影响。通过改变围岩物理力学参数的大小和应力场方向,开展考虑围岩物理力学参数和主应力方向不确定性的地下水封洞库围岩稳定性研究。数值模拟结果表明,当围岩的物理力学参数下降10%时,围岩的位移显著增加,地应力方向改变10%时,围岩位移变化均会增加,说明围岩物理力学参数的变化对稳定性的影响更大,验证主洞室的走向应与地应力方向平行。

关键词：地下水封洞库稳定性围岩物理力学参数地应力方向不确定性

基于应变控制的循环荷载下花岗岩损伤变形研究

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工程勘察 2024年第9期52卷 29-35页

作者：李俊彦彭振华中海油石化工程有限公司济南250014

传统循环荷载试验根据岩石单轴抗压强度来控制循环荷载上限,由于岩样强度具有一定的离散性,导致循环荷载上限难以准确、合理地确定。本文以花岗岩为研究对象,提出一种基于轴向应变控制的循环加卸载试验方案,探究循环荷载作用下岩石的峰... 详细信息

传统循环荷载试验根据岩石单轴抗压强度来控制循环荷载上限,由于岩样强度具有一定的离散性,导致循环荷载上限难以准确、合理地确定。本文以花岗岩为研究对象,提出一种基于轴向应变控制的循环加卸载试验方案,探究循环荷载作用下岩石的峰值应变、峰值强度、弹性模量、泊松比的演化特征。结果表明:对于单轴压缩试验,不同岩样的峰值强度差值较大,而峰值应变相对稳定。从变异系数来看,峰值应变和弹性模量的变异系数较小,相对比较稳定,峰值强度次之,泊松比最不稳定。分析峰值前的应力应变曲线变化趋势,对应力应变曲线分段进行线性拟合,通过斜率变化来判断岩样的屈服状态,进而得到循环荷载试样的轴向应变控制值和循环上限应力,基于此提出了基于应变控制的循环荷载加载方法。对循环加卸载后的岩样进行单轴压缩试验,岩样的应力应变曲线并没有明显差异,只是峰值强度有所降低。对于不同循环次数的岩样,随着循环次数的增加,岩样的峰值强度呈非线性下降趋势,且下降速度逐渐变快。岩样的平均弹性模量呈线性下降趋势,平均泊松比呈非线性上升趋势,且上升趋势逐渐变快。

关键词：花岗岩循环荷载应变控制损伤

Rapid assessment and explanation of tree species abundance along the elevation gradient in Gaoligong Mountains,Yunnan,China

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Chinese Science Bulletin 2007年第A02期52卷 225-231页

作者： SUN zhenhua peng ShengJing OU XiaoKun Institute of Ecology and Geobotany Yunnan University Kunming 650091 China

这篇文章在西方云南在 Gaoligong 山沿着举起坡度与气候的变量介绍树种类丰富和它的协会的分析，中国。从在 Gaoligong 山区的科学报纸和书的数据被收集并且外推阐明由检验气候的变量的沿着坡度的在举起范围和树种类的举起中点之间的举... 详细信息

这篇文章在西方云南在 Gaoligong 山沿着举起坡度与气候的变量介绍树种类丰富和它的协会的分析，中国。从在 Gaoligong 山区的科学报纸和书的数据被收集并且外推阐明由检验气候的变量的沿着坡度的在举起范围和树种类的举起中点之间的举起模式和关系的机械学的理解。树种类丰富与一座山峰显示出一个单峰的模式在中间举起(大约 2000 m ) 并且有一个狭窄的举起范围的种类发生在更高或更低的举起，当一个更宽的举起范围在坡度的中间被发现时。树种类丰富是最高在温度和水可获得性是中等的的地方。在影响种类的气候的变量之间的关系看起来由于在不同坡度改变的这些效果的直接、间接的因素，和效果。

关键词：树种云南省高黎贡山生态系统

Hybrid Krill Herd Algorithm with Vortex Search for Global Numerical Optimization

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Wuhan University Journal of Natural Sciences 2020年第2期25卷 109-117页

作者： YANG Jian WAN Zhongping peng zhenhua School of Mathematics and Statistics Wuhan UniversityWuhan 430072HubeiChina

In order to solve the problem that the krill herd(KH)algorithm is premature due to the decrease of population diversity,a new hybrid vortex search KH(VSKH)algorithm has been developed to deal with the global optimization *** improvement is that a new hybrid vortex search(HVS)operator is added into the updating process of the krill for the purpose of dealing with optimization problems more *** 20 benchmark functions for comparison experiments,the results show that the VSKH algorithm has higher accuracy.

关键词： krill herd algorithm global optimization problem hybrid vortex search operator(HVS)

A Novel Improved Bird Swarm Algorithm for Solving Bound Constrained Optimization Problems

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Wuhan University Journal of Natural Sciences 2019年第4期24卷 349-359页

作者： WANG Yuhe WAN Zhongping peng zhenhua School of Mathematics and Statistics Wuhan University

Bird swarm algorithm(BSA), a novel bio-inspired algorithm, has good performance in solving numerical optimization problems. In this paper, a new improved bird swarm algorithm is conducted to solve unconstrained optimization problems. To enhance the performance of BSA, handling boundary constraints are applied to fix the candidate solutions that are out of boundary or on the boundary in iterations, which can boost the diversity of the swarm to avoid the premature problem. On the other hand, we accelerate the foraging behavior by adjusting the cognitive and social components the sin cosine coefficients. Simulation results and comparison based on sixty benchmark functions demonstrate that the improved BSA has superior performance over the BSA in terms of almost all functions.

关键词： improved bird swarm algorithm handling boundary constraints foraging behavior heuristic algorithm

Key issues in water sealing performance of underground oil storage caverns: Advances and perspectives

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第10期15卷 2787-2802页

作者： Yutao Li Bin Zhang Lei Wang Yiguo Xue Hanxun Wang Lei Shi zhenhua peng Junyan Li School of Engineering and Technology China University of Geosciences(Beijing)Beijing100083China Department of Civil and Architectural Engineering and Construction Management University of CincinnatiCincinnatiOH45221USA CNOOC Petrochemical Engineering Co. Ltd.Qingdao266061China

Water sealing performance is important for underground water-sealed oil storage(UWSOS).The key issues concerning water sealing performance mainly include the permeability of fractured rock mass(FRM),water-sealed safety(WSS),water curtain performance,and prediction and control of water *** paper reviews the progress of above four key issues on water sealing ***,the permeability of an FRM is the basis of water sealing performance,and several commonly used permeability test methods and spatial variation characteristics of permeability are ***,the current water sealing criteria are compared,and the evaluation methods of WSS are ***,the design parameters and efficiency evaluation of water curtain systems(WCSs)are *** water inflow of oil storage caverns(OSCs)can reflect the water sealing effect,and the prediction methods and control measures of water inflow are also ***,the advantages and disadvantages of the current research are discussed,and the potential research directions are pointed out,such as optimization of water sealing criteria and FRM model,quantitative evaluation of WCS efficiency,accurate prediction of water inflow,and improvement of grouting technology.

关键词： Underground water-sealed oil storage (UWSOS) Water-sealed safety(WSS) Water curtain system(WCS) Water inflow Fractured rock mass permeability

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高气液比油井井筒压降实验及理论模型研究

断块油气田 2024年第5期31卷 893-899页

作者：刘永辉吴宁罗程程周陈程李楠彭振华代星方正魁西南石油大学油气藏地质及开发工程全国重点实验室四川成都610500 中国石油塔里木油田分公司新疆库尔勒841000 中国石油勘探开发研究院北京100083 中国石化西北油田分公司新疆乌鲁木齐830011 中国石油新疆油田分公司石西油田作业区新疆克拉玛依834000

深层、超深层油藏中普遍存在着高气液比油井,具有井筒压降大、流动规律复杂的特点。准确预测井筒压降、气体析出位置以及含气率等井筒流动参数对于油井停喷时机预测以及人工举升工艺设计至关重要。为此,文中开展了油-气-水三相流动规律... 详细信息

深层、超深层油藏中普遍存在着高气液比油井,具有井筒压降大、流动规律复杂的特点。准确预测井筒压降、气体析出位置以及含气率等井筒流动参数对于油井停喷时机预测以及人工举升工艺设计至关重要。为此,文中开展了油-气-水三相流动规律模拟实验,分析了气流速、液流速、含水率和井斜角等参数对持液率的影响规律。基于实验结果分析低压实验与高压气井流动相似性,考虑压力变化对气相密度的影响,修正了气液相无因次准数,建立了新持液率计算模型,模型与实验结果相对百分误差和绝对百分误差仅为0.88%和12.50%。进而建立了高气液比油井井筒压降预测模型,采用47口油井现场实际生产测压数据验证新压降模型,结果表明新模型相对性能系数在所有评价模型中最低,仅为0.22,表明模型预测精度高,能够满足工程需求。

关键词：高气液比流动规律井筒压降持液率流动相似性

Recent applications of macrocycles in supramolecular catalysis

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Chinese Chemical Letters 2024年第4期35卷 132-141页

作者： Conghui Wang Lei Xu zhenhua Jia Teck-peng Loh College of Advanced Interdisciplinary Science and Technology Henan University of TechnologyZhengzhou 450001China Division of Chemistry and Biological Chemistry School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore Institute of Advanced Synthesis School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816China

Numerous supramolecular macrocycles have been utilized for developing catalysts by exploiting their specific molecular recognition and ability to form inclusion complexes through noncovalent interactions. The cyclic structure and modified functional groups of these macrocycles can influence substrate and transition state stability, as well as reaction selectivity. The inner cavities of these macrocycles are particularly beneficial, as they enable substrates to adopt preorganized arrangements and serve as versatile platforms for highly efficient supramolecular catalytic systems. This minireview provides an overview of recent advancements in supramolecular catalysis using various macrocycles, such as crown ethers, cyclodextrins,calixarenes, pillararenes, cucurbiturils, and other novel macrocycles.

关键词： Supramolecular catalysis Macrocycle Host-guest interactions Confinement Selectivity

Strategies for constructing seven-membered rings:Applications in natural product synthesis

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Chinese Chemical Letters 2024年第6期35卷 53-70页

作者： peng Chen Lijuan Liang Yufei Zhu Zhimin Xing zhenhua Jia Teck-peng Loh College of Advanced Interdisciplinary Science and Technology Henan University of TechnologyZhengzhou 450001China Division of Chemistry and Biological Chemistry School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore Institute of Advanced Synthesis School of Chemistry and Molecular Engineering Nanjing Tech UniversityNanjing 211816China State Key Laboratory of Applied Organic Chemistry Department of ChemistryLanzhou UniversityLanzhou 730000China

The seven-membered ring motifs are found in bioactive pharmaceuticals and a wide range of natural products,including alkaloids and terpenoids,which hold significant importance in synthetic chemistry and has garnered considerable attention from both academia and *** the challenges faced in the past decade,the total synthesis of natural products incorporating the non-aromatic cycloheptane skeletons remains a compelling ***,numerous elegant strategies for constructing the sevenmembered ring system have been successfully *** review focuses on the recent advancements in this field from 2017 to April 2023,highlighting key transformations utilized to construct the non-aromatic cycloheptane core structures and serves as a valuable guide for synthetic chemists engaged in the total synthesis of natural products containing seven-membered ring motifs.

关键词： Seven-membered rings Total synthesis Natural products Synthetic strategy Cycloheptane