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Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 538-550页

作者： bing q.li Michela Casanova Herbert H.Einstein Department of Civil and Environmental Engineering Massachusetts Institute of TechnologyCambridgeUSA Department of Civil and Environmental Engineering Western UniversityLondonCanada School of Architecture Civil and Environmental EngineeringÉcole Polytechnique Fédérale de LausanneLausanneSwitzerland

Hydraulic fracturing is frequently used to increase the permeability of rock formations in energy extraction scenarios such as unconventional oil and gas extraction and enhanced geothermal systems(EGSs).The present study addresses uncertainties in the hydraulic fracturing process pertaining to EGSs in crystalline rock such as ***,there is debate in the literature on the mechanisms(*** and/or shear)by which these fractures initiate,propagate,and *** present experiments on Barre granite with pre-cut flaws where the material is loaded to high far-field stresses close to shear failure,and then the fluid pressure in the flaws is increased to move the Mohr’s circle to the left and observe the initiation and propagation of fractures using high-speed imaging and acoustic emissions(AEs).We find that the hydraulic fractures initiate as tensile microcracks at the flaw tips,and then propagate as a combination of tensile and shear *** focal mechanisms also show elevated levels of tensional microfracturing near the flaw tips during pressurization and final *** then consider a numerical model of the experimental setup,where we find that fractures are indeed likely to initiate at flaw tips in tension even at relatively high far-field stresses of 40 MPa where shear failure is generally expected.

关键词： Acoustic emission(AE) Hydraulic fracturing Enhanced geothermal system(EGS) Microseismicity

Transfer learning framework for multi-scale crack type classification with sparse microseismic networks

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International Journal of Mining Science and Technology 2024年第2期34卷 167-178页

作者： Arnold Yuxuan Xie bing qli Department of Civil and Environmental Engineering Western UniversityLondon N6A 3K7Canada

Rock fracture mechanisms can be inferred from moment tensors(MT)inverted from microseismic ***,MT can only be inverted for events whose waveforms are acquired across a network of *** is limiting for underground mines where the microseismic stations often lack azimuthal ***,there is a need for a method to invert fracture mechanisms using waveforms acquired by a sparse microseismic ***,we present a novel,multi-scale framework to classify whether a rock crack contracts or dilates based on a single *** framework consists of a deep learning model that is initially trained on 2400000+manually labelled field-scale seismic and microseismic waveforms acquired across 692 *** learning is then applied to fine-tune the model on 300000+MT-labelled labscale acoustic emission waveforms from 39 individual experiments instrumented with different sensor layouts,loading,and rock types in *** optimal model achieves over 86%F-score on unseen waveforms at both the lab-and *** model outperforms existing empirical methods in classification of rock fracture mechanisms monitored by a sparse microseismic *** facilitates rapid assessment of,and early warning against,various rock engineering hazard such as induced earthquakes and rock bursts.

关键词： Multi-scale Fracture processes Microseismic Acoustic emission Source mechanism Deep learning

Repetitive traumatic brain injury–induced complement C1–related inflammation impairs long-term hippocampal neurogenesis

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Neural Regeneration Research 2025年第3期20卷 821-835页

作者： Jing Wang bing Zhang Lanfang li Xiaomei Tang Jinyu Zeng Yige Song Chao Xu Kai Zhao Guoqiang liu Youming Lu Xinyan li Kai Shu Department of Neurosurgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Neurosurgery Shanxi Bethune HospitalShanxi Academy of Medical SciencesTongji Shanxi HospitalThird Hospital of Shanxi Medical UniversityTaiyuanShanxi ProvinceChina Department of Pathophysiology School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Institute for Brain Research Wuhan Center of Brain ScienceHuazhong University of Science and TechnologyWuhanHubei ProvinceChina Department of Graduate Student Chongqing Medical UniversityChongqingChina Department of Basic Medicine School of Medical ScienceHubei University for NationalitiesEnshiHubei ProvinceChina Department of Anatomy School of Basic Medicine and Tongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Repetitive traumatic brain injury impacts adult neurogenesis in the hippocampal dentate gyrus,leading to long-term cognitive ***,the mechanism underlying this neurogenesis impairment remains *** this study,we established a male mouse model of repetitive traumatic brain injury and performed long-term evaluation of neurogenesis of the hippocampal dentate gyrus after repetitive traumatic brain *** results showed that repetitive traumatic brain injury inhibited neural stem cell proliferation and development,delayed neuronal maturation,and reduced the complexity of neuronal dendrites and *** with repetitive traumatic brain injuryalso showed deficits in spatial memory ***,following repetitive traumatic brain injury,neuroinflammation was enhanced in the neurogenesis microenvironment where C1q levels were increased,C1q binding protein levels were decreased,and canonical Wnt/β-catenin signaling was *** inhibitor of C1 reversed the long-term impairment of neurogenesis induced by repetitive traumatic brain injury and improved neurological *** findings suggest that repetitive traumatic brain injury–induced C1-related inflammation impairs long-term neurogenesis in the dentate gyrus and contributes to spatial memory retrieval dysfunction.

关键词： complement C1 dendrite dentate gyrus hippocampus neural stem cell neurogenesis neuroinflammation neurological function neuron traumatic brain injury

Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural Regeneration Research 2025年第6期20卷 1764-1775页

作者： Zhenzhong Zheng Jialin Chen Jinghong Xu Bin Jiang Lei li Yawei li Yuliang Dai bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood RNA profiles spinal cord injury

DYNAMIC MODEL AND SIMULATION OF EAF STEELMAKING PROCESS

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Acta Metallurgica Sinica(English Letters) 2003年第3期16卷 197-203页

作者： q.li X.Hong Shanghai Enhanced Laboratory of Ferrometallurgy Shanghai University Shanghai 200072 ChinaShanghai Enhanced Laboratory of Ferrometallurgy Shanghai University Shanghai 200072 China

Based on mass and energy balances and theories of thermodynamics and kinetics, a dynamic model in conjunction with relative operation parameters was derived. With this model, the EAF process in later stage of scarp melting was dynamically described, including time dependent variations of bath temperature, slag quantity, compositions of steel, slag and off-gas, etc. Steelmaking process in a domestic 100 ton UHP AC EAF was chosen as a computational example, and the simulated variations of temperature of hot metal and element contents was shown consistent with the actual process measurements within average error scopes of |△T| <15K, |[△A%C]| ≤ 0.036, |[△%Si]|≤0.00027, |[△%Mn]|≤0.002, |[△%P]|≤0.00089 and |[△%S]|≤0.001 respectively at the test points. The model will be extended to predict the whole production process including scrap melting procedure and evaluate its energy and material consumption, the production efficiency, etc., which will provide assistance for the improvement of EAF operation and control.

关键词： EAF dynamic model simulation

Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 528-547页

作者： Jiaolong liu Siyu Zhang Dan qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen li Peijun Zhang Yuqi Zhou Kai Tao Mengyang li bing Wei Hongjing Wu Mengyang li bing Wei Hongjing Wu School of Physics Xidian UniversityXi’an 710071People’s Republic of China School of Advanced Materials and Nanotechnology State Key Discipline Laboratory of Wide Band Gap Semiconductor TechnologyXidian UniversityXi’an 710071People’s Republic of China School of Microelectronics Xidian UniversityXi’an 710071People’s Republic of China School of Telecommunication Engineering Xidian UniversityXi’an 710071People’s Republic of China MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary School of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China The Ministry of Education Key Laboratory of Micro and Nano Systems forAerospace School of Mechanical EngineeringNorthwestern PolytechnicalUniversityXi’an 710072People’s Republic of China

Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic *** methods,however,constrain their delicate ***,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon *** unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial ***“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first ***,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric *** defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response.

关键词： Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption

Mediating role of health literacy in the relationship between social isolation and psychological distress among pre-frail older adults

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World Journal of Psychiatry 2025年第1期15卷 137-144页

作者： Juan Fang li-Hui li Ming-qian He Yue Ji Dong-Yan Lu li-bing Zhang Jin-Lan Yao School of Medicine Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Frailty has become a significant public health *** recent increase in the number of frail older adults has led to increased attention being paid to psycho-logical care services in *** social isolation of pre-frail older adults can impact their psychological *** To explore the mediating effect of health literacy between social isolation and psychological distress among communitydwelling older adults with *** This descriptive cross-sectional study was conducted with 254 pre-frail older individuals aged 60 years and *** isolation,health literacy,and psycholo-gical distress were comprehensively measured using the Lubben Social Network Scale-6,12-item Short-Form Health literacy questionnaire,and the Kessler Psy-chological Distress *** were evaluated using the SPSS 27.0 package program and the PROCESS macro *** statistical analyses,correlation analyses,and bootstrap mediation tests were used to assess associations between the *** The results showed that social isolation had an effect on health literacy among pre-frail older adults(β=0.240,Pliteracy was identified effect on psychological distress among pre-frail older persons(β=-0.307,Pliteracy partially mediated the relationship between social isolation and psychological distress among community-dwelling older adults with pre-frailty,with a mediation effect of-0.074,accounting for 17.83%of the total effect.

关键词： Frail Ageing Psychological distress Health literacy Social isolation

Hardness-thermal stability synergy in nanograined Ni and Ni alloys:Superposition of nanotwin and low-energy columnar boundary

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Journal of Materials Science & Technology 2023年第6期137卷 123-131页

作者： F.H.Duan Y.lin q.li J.H.Luan J.Lu J.Pan Y.li Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Laboratory of Nanomaterials&Nanomechanics Department of Mechanical EngineeringCity University of Hong KongHong KongChina State Key Laboratory of Material Processing and Die&Mould Technology and School of Materials Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Department of Materials Science and Engineering City University of Hong KongHong KongChina Centre for Advanced Structural Materials Greater Bay Joint DivisionShenyang National Laboratory for Materials ScienceCity University of Hong Kong Shenzhen Research InstituteShenzhen 518057China City U-Shenzhen Futian Research Institute Shenzhen 518045China

Refining grains into nanoscale can significantly strengthen and harden metallic materials;however,nanograined metals generally exhibit low thermal stability,hindering their practical *** this work,we exploit the superposition of the contribution of nanotwins,low-angle grain boundaries,and microalloying to tailor superior combinations of high hardness and good thermal stability in Ni and Ni *** the nanotwinned Ni having a twin thickness of∼2.9 nm and grain size of 28 nm,it exhibits a hardness over 8.0 GPa and an onset coarsening temperature of 623 K,both of which are well above those of nanograined ***/Mo microalloying can further improve the onset coarsening temperature to 773 K without comprising *** analyses reveal that high hardness is achieved via strengthen-ing offered by extremely fine ***,the superior thermal stability is mainly ascribed to the low driving force for grain growth induced by the low-angle columnar boundary architecture and to the additional pinning effect on the migration of twin/columnar boundaries provided by minor Re/Mo *** present work not only reveals a family of nanotwinned metals possessing the combination of ultra-high hardness and high thermal stability but also provides a strategy for tailoring properties of metallic materials by pairing low-angle grain boundaries and twin boundaries.

关键词： Nanotwin Thermal stability Hardness Low-angle grain boundary Microalloying

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因地制宜发展新质生产力的学理阐释

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 39-47页

作者：李传兵任平阳贵州大学长征文化研究院贵州贵阳550025 贵州大学中共党史党建研究院贵州贵阳550025 贵州大学马克思主义学院贵州贵阳550025 贵州大学哲学学院贵州贵阳550025

因地制宜发展新质生产力是我国经济发展领域的重要课题,科学合理发展新质生产力是推动经济持续增长和提升全民福祉的关键所在。文本在系统把握因地制宜中的“时”“业”“域”特点,深入挖掘因地制宜发展新质生产力理论内涵的基础上,从... 详细信息

因地制宜发展新质生产力是我国经济发展领域的重要课题,科学合理发展新质生产力是推动经济持续增长和提升全民福祉的关键所在。文本在系统把握因地制宜中的“时”“业”“域”特点,深入挖掘因地制宜发展新质生产力理论内涵的基础上,从马克思主义哲学角度与中国特色社会主义建设的具体实践角度探讨其生成依据,围绕制度、发展、主体、创新四个向度阐述因地制宜发展新质生产力的价值旨归。通过对立足地方实际、直面地方问题、汇聚地方力量和激发地方活力四个方面的实践探赜,重点揭示如何将因地制宜发展新质生产力理论转化为可落地的务实行动,推动新质生产力进一步发展。

关键词：新质生产力因地制宜高质量发展实事求是学理阐释

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熔盐罐罐底角焊缝疲劳可靠性评估方法及应用

西安交通大学学报 2025年第1期59卷 215-224页

作者：俞兵胡海军谢国山李涌泉李秀峰西安交通大学化学工程与技术学院西安710049 中国特种设备检测研究院北京100029 国家市场监督管理总局技术创新中心(炼油与化工装备风险防控) 北京100029

为了准确评估熔盐罐罐底角焊缝服役过程中的疲劳可靠性,将应力影响因素和疲劳模型参数随机化,提出了一种基于应力-强度干涉理论的角焊缝疲劳可靠性评估方法。通过雨流计数法获得典型的熔盐液位变化幅值并统计其出现频率;建立了真实尺寸... 详细信息

为了准确评估熔盐罐罐底角焊缝服役过程中的疲劳可靠性,将应力影响因素和疲劳模型参数随机化,提出了一种基于应力-强度干涉理论的角焊缝疲劳可靠性评估方法。通过雨流计数法获得典型的熔盐液位变化幅值并统计其出现频率;建立了真实尺寸的角焊缝数值模型并获得其应力分布;基于角焊缝尺寸、载荷等应力影响因素的正态分布模型,应用拉丁超立方抽样方法对其抽样统计,从而获得角焊缝焊趾处等效结构应力的分布模型;对ASME BPVC.Ⅷ.2—2023标准中疲劳寿命模型的主应力-寿命曲线参数进行随机化,基于应力-强度干涉理论,建立了角焊缝疲劳可靠性评估模型;对某光热装置低温熔盐罐罐底角焊缝的疲劳可靠性进行实例分析。结果表明:一个季度内熔盐罐液位变化主要有6种典型工况,最大液位波动为1.55~12.39 m;角焊缝最大应力位于其内侧焊趾处,为301.5 MPa;多载荷下角焊缝的疲劳寿命均值为46 a,服役3 a后角焊缝的疲劳失效概率为0.040 6,服役30 a后的失效概率为0.335 9。

关键词：熔盐罐角焊缝应力-强度干涉模型疲劳可靠性

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