针对海上油田中油基泥浆滤液侵入导致的储层核磁共振(Nuclear Magnetic Resonance,NMR)测井横向弛豫时间(Transverse Relaxation Time,T_(2))谱“拖尾”现象,提出了一种基于储层物性约束的T_(2)谱分段校正方法,并研发了可挂接于CIFLog...针对海上油田中油基泥浆滤液侵入导致的储层核磁共振(Nuclear Magnetic Resonance,NMR)测井横向弛豫时间(Transverse Relaxation Time,T_(2))谱“拖尾”现象,提出了一种基于储层物性约束的T_(2)谱分段校正方法,并研发了可挂接于CIFLog测井综合解释平台的插件模块。该方法以渗透率为校正判别阈值,按孔隙度分段构建多级物性区间,结合流体类型特征建立校正系数数据库,并在算法中引入积分面积守恒约束,确保校正前后T_(2)谱总面积一致,从物理层面保持孔隙度的真实性。模块采用插件化设计,实现了数据自动匹配、系数管理、计算可视化及结果输出等功能。南海北部湾盆地两口油基泥浆井的应用结果表明,校正后T_(2)谱“拖尾”现象得到明显抑制,长弛豫时间端幅值较原始T_(2)谱平均降低6.86%~10.61%,谱形与储层物性特征更加一致,测井解释结果与常规曲线及岩心资料匹配良好,验证了所建方法的稳定性与工程适用性。研究成果为复杂钻井条件下的核磁测井定量解释提供了可靠的技术支撑。展开更多
We report a theoretical investigation into superconductivity within the MAXH_(6) quaternary hydride system using first-principles calculations,where M and A denote alkali and alkaline earth elements,respectively,and X...We report a theoretical investigation into superconductivity within the MAXH_(6) quaternary hydride system using first-principles calculations,where M and A denote alkali and alkaline earth elements,respectively,and X represents transition metal elements.Systematic analysis of electronic band structures,phonon dispersions,and electron-phonon coupling reveals that substitution of MA binary metal combinations and X metal atoms can create favorable conditions for superconductivity.Mapping of superconducting critical temperatures,combined with dynamical stability analysis through phonon calculations,identifies ten superconducting candidates at ambient pressure.Among these,LiNaAgH_(6) exhibits nearly-free-electron behavior reminiscent of monovalent electron superconductors.It demonstrates exceptional superconducting properties with electron–phonon coupling λ=2.707,which yields a superconducting transition temperature T_(c) of 206.4 K using the Allen–Dynes formula.Its structural analogs MgNaPdH_(6),LiMgPdH_(6),LiMgAgH_(6),LiMgAuH_(6) all exhibit superconducting transition temperatures above 110 K.These findings advance our fundamental understanding of superconductivity in quaternary hydrides and provide guidance for rational design of new high-temperature superconducting materials.展开更多
文摘针对海上油田中油基泥浆滤液侵入导致的储层核磁共振(Nuclear Magnetic Resonance,NMR)测井横向弛豫时间(Transverse Relaxation Time,T_(2))谱“拖尾”现象,提出了一种基于储层物性约束的T_(2)谱分段校正方法,并研发了可挂接于CIFLog测井综合解释平台的插件模块。该方法以渗透率为校正判别阈值,按孔隙度分段构建多级物性区间,结合流体类型特征建立校正系数数据库,并在算法中引入积分面积守恒约束,确保校正前后T_(2)谱总面积一致,从物理层面保持孔隙度的真实性。模块采用插件化设计,实现了数据自动匹配、系数管理、计算可视化及结果输出等功能。南海北部湾盆地两口油基泥浆井的应用结果表明,校正后T_(2)谱“拖尾”现象得到明显抑制,长弛豫时间端幅值较原始T_(2)谱平均降低6.86%~10.61%,谱形与储层物性特征更加一致,测井解释结果与常规曲线及岩心资料匹配良好,验证了所建方法的稳定性与工程适用性。研究成果为复杂钻井条件下的核磁测井定量解释提供了可靠的技术支撑。
基金supported by the National Key R&D Program of China (Grant No.2022YFA1403201)the National Natural Science Foundation of China (Grant Nos.12125404,T2495231,123B2049,and 12204138)+9 种基金the Advanced MaterialsNational Science and Technology Major Project (Grant No.2024ZD0607000)the Natural Science Foundation of Jiangsu Province (Grant Nos.BK20233001 and BK20253009)the Jiangsu Funding Program for Excellent Postdoctoral Talent (Grant No.2024ZB002)the China Postdoctoral Science Foundation (Grant No.2025M773331)the Fundamental and Interdisciplinary Disciplines Breakthrough Plan of the Ministry of Education of Chinathe AI&AI for Science program of Nanjing UniversityArtificial Intelligence and Quantum physics (AIQ) program of Nanjing Universitythe Fundamental Research Funds for the Central Universitiesthe Natural Science Foundation of Nanjing University of Posts and Telecommunications(Grant Nos.NY224165,NY220038,and NY219087)the Hua Li Talents Program of Nanjing University of Posts and Telecommunications。
文摘We report a theoretical investigation into superconductivity within the MAXH_(6) quaternary hydride system using first-principles calculations,where M and A denote alkali and alkaline earth elements,respectively,and X represents transition metal elements.Systematic analysis of electronic band structures,phonon dispersions,and electron-phonon coupling reveals that substitution of MA binary metal combinations and X metal atoms can create favorable conditions for superconductivity.Mapping of superconducting critical temperatures,combined with dynamical stability analysis through phonon calculations,identifies ten superconducting candidates at ambient pressure.Among these,LiNaAgH_(6) exhibits nearly-free-electron behavior reminiscent of monovalent electron superconductors.It demonstrates exceptional superconducting properties with electron–phonon coupling λ=2.707,which yields a superconducting transition temperature T_(c) of 206.4 K using the Allen–Dynes formula.Its structural analogs MgNaPdH_(6),LiMgPdH_(6),LiMgAgH_(6),LiMgAuH_(6) all exhibit superconducting transition temperatures above 110 K.These findings advance our fundamental understanding of superconductivity in quaternary hydrides and provide guidance for rational design of new high-temperature superconducting materials.
