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Changes in microstructure and properties of weld heat-affected zone of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第8期31卷 2041-2052页

作者： Shu-jun Jia Qi-lin Ma Yu Hou Ba Li He-song Zhang Qing-you liu Central Iron and Steel Research Institute Co. Ltd.Beijing 100081China Collaborative Innovation Center for Steel Commonality University of Science and Technology BeijingBeijing 100083China Construction Project Management Branch of China National Petroleum Pipeline Network Group Co. Ltd.Langfang 065000HebeiChina

The evolution of the microstructure and toughness of APL5L X80 pipeline steel after thermal welding simulation was investigated by X-ray diffraction,electron backscatter diffraction,and transmission electron *** results indicated that primary heat-affected zones can be divided into weld,coarse-grained,fine-grained,intercritical,and sub-critical *** microstructure of the weld zone is mainly composed of bainitic ferrite and a small amount of granular bainite;however,the original austenite grains are distributed in the columnar *** structure of the coarse-grained zone is similar to that of the weld zone,but the original austenite grains are *** contrast,the microstructure in the fine-grained zone is dominated by fine granular bainite,and the effective grain size is only 8.15μm,thus providing the highest toughness in the entire heat-affected *** intercritical and subcritical zones were brittle valley regions,and the microstructure was dominated by granular ***,the martensite-austenite(M/A)constituents are present in island chains along the grain boundaries,and the coarse size of the M/A constituents seriously reduces the *** results of the crack propagation analyzes revealed that high-angle grain boundaries can significantly slow down crack growth and change the crack direction,thereby increasing the material *** impact toughness of the low-temperature tempering zone was equivalent to that of the columnar grain zone,and the impact toughness was between those of the critical and fine-grained zones.

关键词： Welding thermal simulation Impact toughness Crack propagation Martensite-austenite constituent High-strength low-alloy steel weld Heat-affected zone

Impact of volcanism on the formation and hydrocarbon generation of organic-rich shale in the Jiyang Depression, Bohai Bay Basin, China

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Petroleum Science 2024年第3期21卷 1539-1551页

作者： Jia-Hong Gao Xin-Ping Liang Zhi-Jun Jin Quan-you liu Chang-Rong Li Xiao-Wei Huang Ju-Ye Shi Peng Li State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development Institute of EnergyPeking University Petroleum Exploration and Production Research Institute SINOPECBeijing100871 China School of Energy Resources China University of Geosciences Beijing100083 China

Globally,most organic-rich shales are deposited with volcanic ash *** ash,a source for many sedimentary basins,can affect the sedimentary water environment,alter the primary productivity,and preserve the organic matter(OM)through physical,chemical,and biological *** an increasing number of breakthroughs in shale oil exploration in the Bohai Bay Basin in recent years,less attention has been paid to the crucial role of volcanic impact especially its influence on the OM enrichment and hydrocarbon ***,we studied the petrology,mineralogy,and geochemical characteristics of the organic-rich shale in the upper submember of the fourth member(Es_(4)^(1))and the lower submember of the third member(Es_(3)^(3))of the Shahejie Formation,aiming to better understand the volcanic impact on organic-rich shale *** results show that total organic carbon is higher in the upper shale intervals rich in volcanic ash with enriched light rare earth elements and moderate Eu *** indicates that volcanism promoted OM formation before or after the *** positive correlation between Eu/Eu*and Post-Archean Australian Shale indicates hydrothermal activity before the volcanic *** plane graph of the hydrocarbon-generating intensity(S1+S2)suggests that the heat released by volcanism promoted hydrocarbon ***,the nutrients carried by volcanic ash promoted biological blooms during Es_(4)^(1 )and Es_(3)^(3) deposition,yielding a high primary *** blooms consume large amounts of oxygen and form anoxic environments conducive to the burial and preservation of ***,this study helps to further understand the organic-inorganic interactions caused by typical geological events and provides a guide for the next step of shale oil exploration and development in other lacustrine basins in China.

关键词： Volcanic ash Hydrocarbon generation Organic-rich shale Shahejie Formation Jiyang Depression

Degradation of warm permafrost and talik formation on the Qinghai-Tibet Plateau in 2006-2021

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Advances in Climate Change Research 2024年第2期15卷 275-284页

作者： Qi-Hang MEI Ji CHEN you-Qian liu Shou-Hong ZHANG Jing-Yi ZHAO Tian-Chun DONG Jun-Cheng WANG Yao-Jun ZHAO Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment Key Laboratory of Cryospheric Science and Frozen Soil EngineeringNorthwest Institute of Eco-Environmental and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co.Ltd Xining 810007China University of Chinese Academy of Sciences Beijing 100049China

Permafrost is degrading globally,particularly those with low thermal stability on the Qinghai-Tibet Plateau,owing to climate ***,the inadequacy of direct research on permafrost degradation based on in-situ monitoring limits the prediction of permafrost degradation and engineering *** study explored the processes and modes of permafrost degradation into talik by analyzing ground temperature data from five points in the hinterland of the Qinghai-Tibet Plateau from 2006 to *** results showed that the degradation of the warm permafrost layer with a geothermal gradient of zero occurred simultaneously in the top and bottom *** rate of permafrost degradation from the top down and bottom up increase during the degradation process,but the increase of the former is more drastic after the formation of thawed ***,the construction of the Qinghai-Tibet Railway changed the degradation modes of the permafrost in adjacent natural sites through horizontal heat transfer,particularly after through talik formation under the *** findings suggest that taking countermeasures before or immediately after forming thawed interlayer is more *** evaluating the thermal impact of projects in warm permafrost regions,special attention should be given to the horizontal heat transfer process that may result from the formation of a through talik.

关键词： Warm permafrost Degradation Talik Qinghai-Tibet Plateau Climate change

Enhancing the crystallinity and stability of perovskite solar cells with 4-tert-butylpyridine induction for efficiency exceeding 24%

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Journal of Energy Chemistry 2024年第6期93卷 1-7,I0001页

作者： you liu Lishuang Zheng Kuanxiang Zhang Kun Xu Weicheng Xie Jue Zhang Yulu Tian Tianyuan liu Hanzhong Xu Ruoming Ma Wei Huang Jiahui Chen Jusheng Bao Chen Chen Yongsheng Zhou Xuchun Wang Junming Chen Jungan Wang College of Chemistry and Materials Engineering Anhui Science and Technology UniversityBengbu 233000AnhuiChina Anhui Province Quartz Sand Purification and Photovoltaic Glass Engineering Research Center Chuzhou 233100AnhuiChina Triumph Photovoltaic Materials Co.Ltd BengbuAnhuiChina National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210009JiangsuChina JinkoSolar Holding Co.Ltd HainingZhejiangChina

Perovskite solar cells(PSCs)have emerged as a promising photovoltaic technology because of their high light absorption coefficient,long carrier diffusion distance,and tunable ***,PSCs face challenges such as hysteresis effects and stability *** this study,we introduced a novel approach to improve film crystallization by leveraging 4-tert-butylpyridine(TBP)molecules,thereby enhancing the performance and stability of *** findings demonstrate the effective removal of PbI_(2)from the perovskite surface through strong coordination with TBP ***,by carefully adjusting the concentration of the TBP solution,we achieved enhanced film crystallinity without disrupting the perovskite *** TBP-treated perovskite films exhibit a low defect density,improved crystallinity,and improved carrier *** a result,the PSCs manufactured with TBP treatment achieve power conversion efficiency(PCE)exceeding 24%.Moreover,we obtained the PCE of 21.39%for the 12.25 cm^(2)module.

关键词： 4-tert-butylpyridine Film crystallization Perovskite solar cells Power conversion efficiency Stability improvement

地铁列车关键气密部件对车内压力舒适性的影响

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交通运输工程学报 2024年第3期24卷 227-237页

作者：李杨刘友梅中车株洲电力机车有限公司湖南株洲412001

为全面分析地铁列车运营时车外压力对车内乘客耳压舒适性的影响,采用实车线路试验方法,实测了地铁列车匀速通过隧道时,关键气密部件(空调压力波保护阀、车门气动辅助锁与贯通道排污孔筛)在不同密封条件下的车内、外压力,分析了车外压力... 详细信息

为全面分析地铁列车运营时车外压力对车内乘客耳压舒适性的影响,采用实车线路试验方法,实测了地铁列车匀速通过隧道时,关键气密部件(空调压力波保护阀、车门气动辅助锁与贯通道排污孔筛)在不同密封条件下的车内、外压力,分析了车外压力波动特性、沿列车长度方向的压力分布规律以及车内关键气密部件对车内压力变化幅值的影响。研究结果表明:头车和中间车的车外压力受车头进入隧道产生的压缩波影响较大,列车车身表面压力峰值从头车向尾车逐渐降低;在空调开启时,相较于启用压力波保护阀,未启用时车内3 s内压力变化幅值增加了48%~61%,1 s内增加了75%~90%,说明空调压力波保护阀对车内压力舒适性影响显著;在空调关闭时,与启用车门气动辅助锁相比,未启用时3 s内车内压力变化幅值增加了39%~46%,1 s内增加了69%~78%,表明车门气动辅助锁对车内压力舒适性的影响仅次于空调压力波保护阀;在空调关闭的情况下,与启用贯通道排污孔筛相比,未启用时3 s内车内压力变化幅值增加了3%~11%,1 s内增加了1%~13%,说明贯通道排污孔筛对车内压力的影响较小。

关键词：车辆工程地铁列车实车试验压力波气密性舒适性

A_(2)权调和Bergman空间上正符号Toeplitz算子

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数学学报（中文版） 2024年第3期67卷 468-481页

作者：刘柚岐夏锦王晓峰广州大学数学与信息科学学院广州510006 重庆工商大学数学与统计学院重庆400067

本文讨论了n维实空间中有界光滑域的A_(2)权调和Bergman空间上正符号Toeplitz算子.通过平均函数和Berezin变换,得到了Toeplitz算子具有有界性和紧性的等价条件.同时,也刻画了Schatten类Toeplitz算子.

关键词： A_(2)权调和Bergman空间 Toeplitz算子有界性紧性 Schatten类

基于数据驱动的氮杂多环含能化合物的开发研究进展

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含能材料 2024年第6期32卷 660-671页

作者：刘友海黄实张文全杨福胜中国工程物理研究院化工材料研究所四川绵阳621999 西安交通大学化学工程与技术学院陕西西安710049

含能材料的开发面临诸多挑战,传统“试错法”的研发模式会导致研发周期长,效率低。随着数据科学与人工智能技术的发展,基于数据驱动的研发模式为含能材料的发展开辟了新的路径。多环含能化合物是当前含能材料学科的研究热点,其中氮杂多... 详细信息

含能材料的开发面临诸多挑战,传统“试错法”的研发模式会导致研发周期长,效率低。随着数据科学与人工智能技术的发展,基于数据驱动的研发模式为含能材料的发展开辟了新的路径。多环含能化合物是当前含能材料学科的研究热点,其中氮杂多环骨架由于存在π电子的离域共振和较多的可修饰位点,分子结构的稳定性得到提高,同时能量基团的存在保证了分子的能量水平,使得能量与稳定性之间的固有矛盾得到很好的平衡。研究简要介绍了数据驱动开发新型含能材料的工作流程,概述了数据驱动方法用于氮杂多环含能化合物开发的最新研究进展,最后对数据驱动的方法用于新型含能材料的开发提出展望。未来的发展方向应考虑通过数据增强、治理等手段补充数据量,以提高模型预测的准确性及泛化能力;可通过建立化学反应条件和合成路径筛选的机器学习模型预测分子的可合成性,从而加速新型氮杂多环含能化合物的开发。

关键词：含能材料数据驱动氮杂多环含能化合物机器学习

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船载膜进样质谱检测湖水中溶解气

分析化学 2024年第7期52卷 937-944页

作者：王晗刘昌杰宋海蕴刘友江陈池来中国科学院合肥物质科学研究院

随着大气中CO2的平均含量逐年攀升和全球气候持续变暖，水生态系统中蓝藻水华的爆发频率、强度和持续时间也逐年增大，对全球生态系统健康造成了严重威胁，引起了全世界的关注。本研究基于研制的膜进样质谱仪ims-UMS，采用船载的方式开... 详细信息

随着大气中CO2的平均含量逐年攀升和全球气候持续变暖，水生态系统中蓝藻水华的爆发频率、强度和持续时间也逐年增大，对全球生态系统健康造成了严重威胁，引起了全世界的关注。本研究基于研制的膜进样质谱仪ims-UMS，采用船载的方式开展了湖水中小分子溶解气的在线检测研究。水质对比研究结果表明，ims-UMS可根据溶解气检测结果实现不同水质的有效区分。在线走航检测结果表明，在无蓝藻覆盖的区域，溶解O2及溶解CO2含量分别为0.24 mmol/L和1.31μmol/L；在蓝藻覆盖区域，二者含量分别为0.21 mmol/L及0.92μmol/L；在蓝藻大量聚集的打捞区域，溶解CO2含量快速上升，而溶解O2含量快速下降。此定量分析结果表明，蓝藻的大规模爆发会加剧CO2排放，此时湖泊将作为CO2源向大气中释放CO2，从而对全球气候变化造成不良影响；同时，蓝藻的大规模爆发会导致溶解O2的含量快速下降，从而导致鱼类和底栖无脊椎动物因缺氧而死亡。研究还发现，O2/CO2比例可以作为蓝藻监测的重要指标，该比例越小，表明蓝藻含量越高；同时，O2/CO2比例与浊度、酸碱度具有强相关性，蓝藻的大规模爆发会增大水的浊度，不利于水生生物生存。本研究为开展水质监测、生态评估尤其为水华蓝藻前期预防、中期治理以及后期治理效果评估等研究提供了重要的技术手段。

关键词：膜进样质谱溶解气在线检测蓝藻

可修复钢制屈曲约束支撑力学性能试验与数值模拟研究

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工程力学 2024年第6期41卷 145-153页

作者：熊琛吴迪晟管民生刘尤森杜宏彪深圳大学广东省滨海土木工程耐久性重点实验室广东深圳518060 深圳大学土木与交通工程学院广东深圳518060

提出了一种可修复钢制屈曲约束支撑(RBRB),该支撑可通过核心板的局部替换实现支撑修复。RBRB各部件采用螺栓连接,无须拆除屈曲约束盖板即可实现核心板修复替换,修复过程简单。设计了两种不同核心板宽度的RBRB试件,并开展低周往复加载试... 详细信息

提出了一种可修复钢制屈曲约束支撑(RBRB),该支撑可通过核心板的局部替换实现支撑修复。RBRB各部件采用螺栓连接,无须拆除屈曲约束盖板即可实现核心板修复替换,修复过程简单。设计了两种不同核心板宽度的RBRB试件,并开展低周往复加载试验,讨论了其滞回性能、失效模式以及累计塑性变形能力。试验结果表明RBRB滞回曲线较为饱满,具有稳定的滞回性能与良好的累计塑性变形能力。RBRB试件在核心板修复后滞回性能与修复替换前保持一致,表明其可修复性较好。对试件开展了数值模拟研究,并与试验结果进行对比,结果显示数值模拟的破坏形式及滞回曲线与试验结果吻合良好。

关键词：屈曲约束支撑可修复拟静力试验滞回性能有限元分析