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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 112-122页

作者： Leilei Jin Hongkai Dong Fei Ye Yufeng Wei jianfeng liu Changkui Wang State Key Laboratory of Hydraulic and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China

Primary toppling usually occurs in layered rock slopes with large anti-dip *** this paper,the block toppling evolution was explored using a large-scale centrifuge *** block column in the layered model slope was made of cement *** artificial cracks perpendicular to the block column were *** gages,displacement gages,and high-speed camera measurements were employed to monitor the deformation and failure processes of the model *** centrifuge test results show that the block toppling evolution can be divided into seven stages,*** compression,formation of major tensile crack,reverse bending of the block column,closure of major tensile crack,strong bending of the block column,formation of failure zone,and complete *** toppling is characterized by sudden large deformation and occurs in *** wedge-shaped cracks in the model incline towards the *** observations show that block toppling is mainly caused by bending failure rather than by shear *** tensile strength also plays a key factor in the evolution of block *** simulation results from discrete element method(DEM)is in line with the testing *** stress exists at the backside of rock column during toppling *** concentration results in the fragmented rock column and its degree is the most significant at the slope toe.

关键词： Block toppling Centrifuge Anti-dip slope Failure mechanism Discrete element method

A thermal stress loading technique for large-sized hot dry rock mechanical tests

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Deep Underground Science and Engineering 2024年第3期3卷 326-337页

作者： Huiling Ci Bing Bai Hongwu Lei Yan Zou jianfeng liu State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhanChina University of Chinese Academy of Sciences BeijingChina State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengduChina

Testing of large-sized specimens is becoming increasingly important in deep underground rock mechanics and *** traditional mechanical loading,stresses on large-sized specimens are achieved by large host frames and hydraulic pumps,which could lead to great ***-cost testing machines clearly always have great *** this study,a new approach is proposed using thermal expansion stress to load rock specimens,which may be particularly suitable for tests of deep hot dry rock with high *** is a different technical route from traditional mechanical loading through hydraulic *** the rock mechanics test system of hot dry rock that already has an investment in heating systems,this technology may reduce the cost of the loading subsystem by fully utilizing the temperature *** paper presents the basic principle and a typical design of this technical *** feasibility analysis is then conducted based on numerical *** some technical details still need to be resolved,the feasibility of this loading approach has been preliminarily confirmed.

关键词： deep rock engineering high-temperature and high-stress conditions hot dry rock large-sized model test thermal stress loading

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A creep model for ultra-deep salt rock considering thermal-mechanical damage under triaxial stress conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 588-596页

作者： Chao Liang jianfeng liu Jianxiong Yang Huining Xu Zhaowei Chen Lina Ran College of Water Resource and Hydropower Sichuan UniversityChengdu610065China CNPC Key Laboratory of Oil and Gas Underground Storage Engineering Langfang065007China CNPC Engineering Technology R&D Company Limited Beijing102206China

To investigate the specific creep behavior of ultra-deep buried salt during oil and gas exploitation,a set of triaxial creep experiments was conducted at elevated temperatures with constant axial pressure and unloading confining pressure *** results show that the salt sample deforms more significantly with the increase of applied temperature and deviatoric *** accelerated creep phase is not occurring until the applied temperature reaches 130℃,and higher temperature is beneficial to the occurrence of accelerated *** describe the specific creep behavior,a novel three-dimensional(3D)creep constitutive model is developed that incorporates the thermal and mechanical variables into mechanical ***,the standard particle swarm optimization(SPSO)method is adopted to fit the experimental data,and the sensibility of key model parameters is analyzed to further illustrate the model *** a result,the model can accurately predict the creep behavior of salt under the coupled thermo-mechanical effect in deep-buried *** on the research results,the creep mechanical behavior of wellbore shrinkage is predicted in deep drilling projects crossing salt layer,which has practical implications for deep rock mechanics problems.

关键词： Creep experiments Creep model Thermal and mechanical damage Fractional derivative

Engineering biomimetic nanosystem targeting multiple tumor radioresistance hallmarks for enhanced radiotherapy

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Science China(Life Sciences) 2024年第7期67卷 1398-1412页

作者： Shuxiang Wang Hongmei Cao Cui-Cui Zhao Qian Wang Dianyu Wang Jinjian liu Lijun Yang jianfeng liu State Key Laboratory of Advanced Medical Materials and Devices Tianjin Key Laboratory of Radiation Medicine and Molecular Nuclear MedicineKey Laboratory of Radiopharmacokinetics for Innovative DrugsTianjin Institutes of Health ScienceInstitute of Radiation MedicineChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300192China Tianjin Medical University Cancer Institute and Hospital National Clinical Research Center for CancerTianjin’s Clinical Research Center for CancerKey Laboratory of Cancer Prevention and Therapy(Tianjin)Key Laboratory of Breast Cancer Prevention and TherapyTianjin Medical UniversityMinistry of EducationTianjin 300060China

Tumor cells establish a robust self-defense system characterized by hypoxia,antioxidant overexpression,DNA damage repair,and so forth to resist *** one of these features is insufficient to overcome radioresistance due to the feedback mechanisms initiated by tumor cells under ***,we herein developed an engineering biomimetic nanosystem(M@HHPt)masked with tumor cell membranes and loaded with a hybridized protein-based nanoparticle carrying oxygens(O_(2))and cisplatin prodrugs(Pt(Ⅳ))to target multiple tumor radioresistance hallmarks for enhanced *** administration,M@HHPt actively targeted and smoothly accumulated in tumor cells by virtue of its innate homing abilities to realize efficient co-delivery of O_(2)and Pt(Ⅳ).O_(2)introduction induced hypoxia alleviation cooperated with Pt(Ⅳ)reduction caused glutathione consumption greatly amplified radiotherapy-ignited cellular oxidative ***,the released cisplatin effectively hindered DNA damage repair by crosslinking with radiotherapy-produced DNA ***,M@HHPt-sensitized radiotherapy significantly suppressed the proliferation of lung cancer H1975 cells with an extremely high sensitizer enhancement ratio of 1.91 and the progression of H1975 tumor models with an excellent tumor inhibition rate of 94.7%.Overall,this work provided a feasible strategy for tumor radiosensitization by overcoming multiple radioresistance mechanisms.

关键词： biomimetic nanosystem hypoxia alleviation glutathione consumption oxidative stress amplification DNA damage fixation radiosensitization

SiRAP2-12,a Positive Regulatory Factor,Effectively Improves the Waterlogging Tolerance of Foxtail Millet(Setaria italica)

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Phyton-International Journal of Experimental Botany 2024年第3期93卷 445-465页

作者： Xueyan Xia Xiaohong Fu Yu Zhao Jihan Cui Nuoya Xiao Jingxin Wang Yiwei Lu Meihong Huang Cheng Chu Jia Zhang Mengxin Yang Shunguo Li jianfeng liu Institute of Millet Crops Hebei Academy of Agriculture and Forestry Sciences/Key Laboratory of Genetic Improvement and Utilization for Featured Coarse Cereals(Co-Construction byMinistry and Province)Ministry of Agriculture and Rural Affairs/The Key Research Laboratory of Minor Cereal Crops of Hebei ProvinceShijiazhuang050035China School of Life Sciences Institute of Life Science and Green DevelopmentHebei UniversityBaoding071002China

Foxtail millet(Setaria italica)growth was inhibited because of waterlogging stress,which has caused yield *** family plays an important role to plant adversity *** our study,we obtained 19,819 differential expressed genes(DEGs)between the two treatments based on the RNA-seq sequencing of foxtail millet of water-logging ***,a total of 28 ERF family members were obtained,which have a complete open read-ing *** studied the evolution and function of SiERF family and how they affected the waterlogging *** was found that SiERF1A/B/C(GenBank ID:OR775217,OR775219,OR775218)and SiRAP2-12(GenBank ID:OR775216)have similar functions to the known waterlogging tolerance genes of other *** them,the SiRAP2-12 expression was obviously signiﬁcantly up-regulated in foxtail millet after 5d water-logging *** SiRAP2-12 was silenced,the activity of defense enzymes in millet decreased signiﬁ*** details,superoxide dismutase(SOD),catalase(CAT)and peroxidase(POD),the osmotic regulator proline(Pro),and the activity of the anaerobic respiratory enzyme alcohol dehydrogenase(ADH)content were decreased by 78.61%,29.52%,79.95%,19.41%and 54.77%,*** contrast,the relative electrical conductivity contents(REC),malondialdehyde(MDA),and hydrogen peroxide(H_(2)O_(2))of the foxtail millet subjected to virus-induced gene silencing clearly increased by 1.03-fold,36.09%,and 15.21%,*** content of sodium(Na^(+))in the SiRAP2-12-silenced foxtail millet also increased,but that of potassium(K^(+))***,we found that ethylene content was signiﬁcantly ***,the SiAOC1 expression,an essential gene for ethylene synthesis,was inhibited in SiRAP2-12-silenced foxtail millet after waterlogging *** together,we hypothesized that SiRAP2-12 might be a positive regulator of millet tolerance to waterlogging stress.

关键词： Foxtail millet waterlogging SiRAP2-12 VIGS ethylene

单轴压缩条件下单裂隙花岗岩力学特性及破坏特征

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西南交通大学学报 2024年第2期59卷 369-376,446页

作者：王春萍王璐刘建锋刘健核工业北京地质研究院北京100029 国家原子能机构高放废物地质处置创新中心北京100029 四川大学水利水电学院四川成都610065 西华大学建筑与土木工程学院四川成都610039

为研究含贯通单裂隙花岗岩的力学特性及破坏特征,以我国高放废物地质处置甘肃北山预选区完整花岗岩及含倾角30°、45°和60°贯通裂隙的花岗岩为研究对象,开展单轴压缩试验研究.结果表明:裂隙倾角越大,试样的单轴抗压强度、损伤应力以... 详细信息

为研究含贯通单裂隙花岗岩的力学特性及破坏特征,以我国高放废物地质处置甘肃北山预选区完整花岗岩及含倾角30°、45°和60°贯通裂隙的花岗岩为研究对象,开展单轴压缩试验研究.结果表明:裂隙倾角越大,试样的单轴抗压强度、损伤应力以及弹性模量越低;与完整岩石相比,倾角30°、45°和60°裂隙花岗岩的抗压强度分别下降7.97%、29.17%和71.68%,损伤应力分别下降9.35%、24.26%和69.79%,弹性模量分别下降5.89%、23.32%和60.49%.裂隙倾角不同,试样的应力-应变曲线呈现出显著的差别;裂隙倾角越大,损伤应力至峰值应力之间的屈服阶段越明显,发生沿裂隙面滑移破坏特征越显著;裂隙倾角影响花岗岩的破坏模式,试样的破坏形式主要表现为穿裂隙面破坏(倾角30°)、穿裂隙面破坏和沿裂隙面滑移并存的复合破坏(倾角45°)以及沿裂隙面滑移破坏(倾角60°);倾角60°的裂隙花岗岩的抗压强度与试验前后裂隙面的分形维数差符合幂函数增长关系.

关键词：岩石力学单裂隙花岗岩裂隙倾角单轴压缩试验破坏特征

基于漏磁场和ICOA-ResNet的变压器绕组早期故障诊断

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电力系统保护与控制 2024年第9期52卷 99-110页

作者：刘建锋李志远周亚茹上海电力大学电气工程学院上海200090

针对变压器绕组变形、轻微匝间短路故障诊断准确率低的问题,提出一种变压器绕组早期故障诊断方法。首先,利用ANSYS仿真软件建立与实验变压器相关参数一致的有限元模型,分析变压器在绕组发生各种故障的漏磁场分布规律,并根据这些规律选... 详细信息

针对变压器绕组变形、轻微匝间短路故障诊断准确率低的问题,提出一种变压器绕组早期故障诊断方法。首先,利用ANSYS仿真软件建立与实验变压器相关参数一致的有限元模型,分析变压器在绕组发生各种故障的漏磁场分布规律,并根据这些规律选取合适的故障特征以及光纤漏磁场传感器安装位置。然后,通过改进长鼻浣熊优化算法(improved coati optimization algorithm,ICOA)寻找残差神经网络(ResNet)的最优超参数,以此参数构建ICOA-ResNet模型,将所得故障特征量输入模型进行故障诊断。最后,通过仿真数据和动模实验验证所提出的变压器绕组早期故障诊断模型的可行性。所提模型与支持向量机等4种模型相比,在绕组早期故障诊断上有更高的准确率,表明所提方法对变压器绕组变形、匝间短路故障诊断的有效性。

关键词：变压器早期故障诊断绕组变形漏磁场长鼻浣熊优化算法残差神经网络超参数优化

地面机动平台可重构轮履复合推进机构研究现状与展望

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北京理工大学学报 2024年第6期44卷 553-564页

作者：刘城王嘉轩刘建峰魏巍闫清东北京理工大学机械与车辆学院北京100081 北京理工大学长三角研究院(嘉兴) 浙江嘉兴314001 北京理工大学重庆创新中心重庆401147 北京理工大学济南前沿技术研究院山东济南250300

可重构轮履复合推进机构兼具轮式推进机构的快速性和履带推进机构的通过性,是提高地面机动平台在极端地形上综合性能的关键技术,在各类机器人和特种车辆上都得到了一定应用.文中在系统调研国内外相关文献的基础上,按轮履构型重构互换原... 详细信息

可重构轮履复合推进机构兼具轮式推进机构的快速性和履带推进机构的通过性,是提高地面机动平台在极端地形上综合性能的关键技术,在各类机器人和特种车辆上都得到了一定应用.文中在系统调研国内外相关文献的基础上,按轮履构型重构互换原理对推进机构进行分类,着重对比分析了不同构型的结构特点和应用场景,指出了可重构轮履复合推进机构的主要技术难点和发展前景.

关键词：地面机动平台可重构轮履复合通过性

中国与太平洋岛国职业教育合作的现实动力、基础与路径选择

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教育与职业 2024年第20期1068卷 31-38页

作者：刘建峰刘雨晨聊城大学太平洋岛国研究中心山东聊城252000 聊城大学历史文化与旅游学院山东聊城252000

随着“21世纪海上丝绸之路”建设的推进,中国与太平洋岛国在政治、经济、文化等领域的合作不断深入,催生了中国与太平洋岛国职业教育合作的新机遇。全面战略伙伴关系为双方的职教合作擘画了蓝图,深层次教育合作基础为双方的职教合作搭... 详细信息

随着“21世纪海上丝绸之路”建设的推进,中国与太平洋岛国在政治、经济、文化等领域的合作不断深入,催生了中国与太平洋岛国职业教育合作的新机遇。全面战略伙伴关系为双方的职教合作擘画了蓝图,深层次教育合作基础为双方的职教合作搭筑了基石,中资企业“出海”为双方职教国际性产教融合赋能“,职教出海”经验助力双方的职教合作行稳致远。深化中国与太平洋岛国在职业教育领域的合作,不仅是南太平洋地区大国博弈的政治诉求,更是推动岛国产业转型以及经济增长的重要引擎,对于提升岛民就业率、减少贫困具有重要意义。新形势下中国与太平洋岛国的职业教育合作可以尝试以下路径:以政策机制为关键点,引导共创;以示范项目为着力点,激发动能;以政侨企校为突破点,凝心聚力。

关键词：职教出海太平洋岛国职教合作

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再论房价分化之谜--收入不确定性的视角

经济科学 2024年第4期 68-92页

作者：赵扶扬赵娅瑄刘建丰中央财经大学经济学院浙江越秀外国语学院国际商学院

近十年来,我国房价呈现明显的区域分化特征,然而人口流动、土地供给等传统供需因素并不能很好地解释房价分化的现象。本文认为,收入不确定性是解释房价区域间分化的一个重要视角。本文构建了一个包含异质性投资者的动态一般均衡模型,着... 详细信息

近十年来,我国房价呈现明显的区域分化特征,然而人口流动、土地供给等传统供需因素并不能很好地解释房价分化的现象。本文认为,收入不确定性是解释房价区域间分化的一个重要视角。本文构建了一个包含异质性投资者的动态一般均衡模型,着重刻画了收入不确定性对不同地区房价的影响。研究发现:不确定性加速了人口流入地区房价的上升,但也挤出了更多的消费与实体经济。机制分析显示:由于金融不完备性的存在,人们持有的住房资产往往具有“流动性溢价”,住房需求对于预期收益的变化比对当前价格的变化更为敏感。在不确定性上升的情况下,人们会预防性地增持住房资产,提高住房资产的预期收益;同时,人口从低线城市向高线城市的集聚也势必会通过传统供需机制增加人们对于优质房产的投资需求。由此,预防性储蓄机制放大了传统供需机制,两者的联合作用大于两者独立作用的联合,扩大了高线城市与低线城市的房价(增速)差距。最后,本文进行了政策分析,分别考察了在“缓解供需矛盾”和“稳定市场预期”两个核心维度上,保障性住房供给、拓宽投资渠道及“房住不炒”预期指引等政策的实行对经济的影响。研究发现,这些政策均能在一定程度上缓解上述联合效应所带来的房价分化现象,同时也能抑制内需下降及经济脱实向虚的趋势。

关键词：收入不确定性房价分化保障性住房脱实向虚