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节理岩体隧道的稳定性分析及破坏机理

公路工程 2014年第5期39卷 295-299页

作者：彭双喜湖南路桥建设集团公司湖南长沙410004

以往只有位移,应力,尺寸和塑性区分布在分析节理岩体隧道的稳定性时考虑。这样,既不可以明确发现破坏面的位置和范围,也不能得到的安全系数量化标准。定量分析节理岩体隧道稳定性模型试验与数值分析在本文得出了研究。通过使用有限元强... 详细信息

以往只有位移,应力,尺寸和塑性区分布在分析节理岩体隧道的稳定性时考虑。这样,既不可以明确发现破坏面的位置和范围,也不能得到的安全系数量化标准。定量分析节理岩体隧道稳定性模型试验与数值分析在本文得出了研究。通过使用有限元强度折减法计算破坏状态和节理岩体隧道的安全系数。结果表明,联合倾角对破坏面的位置产生更大的影响。如果α=0°时,破坏面对称分布在两侧;如果α=30°和45°,滑动面旋转节随理倾角的变化,并相应地分布在节理的上下部分;如果α≥60°,破坏面转移到底部。特别地,如果α=90°时,可形成拱顶的中间破坏面。安全系数结果表明,安全系数降低了不同程度的节理岩体隧道同质隧道,但节理倾角对安全系数的影响不大相比。节理间距和强度的降低,安全系数降低。

关键词：隧道强度折减有限元法节理安全系数破坏面

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724 W,0.9 mJ,227 fs四通道相干合成超快光纤激光系统(特邀)

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光学学报 2024年第17期44卷 283-290页

作者：王志浩彭双喜徐浩李政言张庆斌陆培祥华中科技大学武汉光电国家研究中心与物理学院湖北武汉430074 华中科技大学光学与电子信息学院湖北武汉430074 湖北光谷实验室湖北武汉430074

报道了一种基于四通道光纤放大器相干光束合成的高功率飞秒激光系统。每个通道均采用大模场棒状光子晶体光纤,平均功率达到220 W。通过稳定的主动相位锁定技术,压缩后的激光系统在800 kHz的重复频率下实现了724 W的平均功率和0.9 mJ的... 详细信息

报道了一种基于四通道光纤放大器相干光束合成的高功率飞秒激光系统。每个通道均采用大模场棒状光子晶体光纤,平均功率达到220 W。通过稳定的主动相位锁定技术,压缩后的激光系统在800 kHz的重复频率下实现了724 W的平均功率和0.9 mJ的单脉冲能量。合成后的激光保持了良好的光束质量和功率稳定性,合束光斑的光束质量因子M^(2)<1.25,功率波动的均方根误差为0.59%。此外,通过优化各通道放大器的增益并测量分析压缩后脉冲的时域特性,实现了对放大前脉冲的精确色散预补偿。本系统在没有使用脉冲整形或者光谱调制的情况下,实现了脉冲宽度从445 fs到227 fs的优化。

关键词：超快光纤激光器相干光束合成啁啾脉冲放大色散补偿

静脉联合局部应用氨甲环酸对髋关节翻修术围手术期失血量的影响

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生物骨科材料与临床研究 2017年第4期14卷 29-32页

作者：燕双喜彭昊陈森武汉大学人民医院骨关节外科湖北武汉430060

目的探讨静脉联合局部应用氨甲环酸(TXA)减少髋关节翻修术围手术期中失血量的有效性和安全性。方法 2014年6月至2016年8月行髋关节翻修术的70例患者随机分为静脉联合局部应用氨甲环酸组与对照组,每组为35例。氨甲环酸组在手术前以10 mg/... 详细信息

目的探讨静脉联合局部应用氨甲环酸(TXA)减少髋关节翻修术围手术期中失血量的有效性和安全性。方法 2014年6月至2016年8月行髋关节翻修术的70例患者随机分为静脉联合局部应用氨甲环酸组与对照组,每组为35例。氨甲环酸组在手术前以10 mg/kg TXA+100 m L生理盐水静脉输注,并在手术中缝合切口时关节腔内注射1 g(1:10 m L)氨甲环酸,对照组采用同一时间注射相同剂量的生理盐水。记录患者术中出血量、输血量、术后引流量,在术后第2天复查患者血常规等指标,并将两组术后深静脉血栓形成的发生率和伤口并发症及住院天数相比较。结果应用静脉联合局部注射氨甲环酸组术中出血量、术后引流量及隐性失血量和输血量均低于对照组,差异有统计学意义(P0.05)。结论静脉联合局部应用氨甲环酸可明显减少全髋关节翻修术围手术期的失血量,并不会增加深静脉血栓形成的发生率。

关键词：氨甲环酸全髋关节置换静脉联合局部失血输血率

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Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-Gui peng peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

Multi boron-doping effects in hard carbon toward enhanced sodium ion storage

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Journal of Energy Chemistry 2025年第1期100卷 730-738页

作者： peng Zheng Wang Zhou Ying Mo Biao Zheng Miaomiao Han Qin Zhong Wenwen Yang peng Gao Lezhi Yang Jilei Liu College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy Hunan Province Key Laboratory for Advanced Carbon Materials and Applied Technology Hunan University Greater Bay Area Institute for Innovation Hunan University Changsha Research Institute of Mining & Metallurgy Co. LTD.

Hard carbon （HC） has been considered as promising anode material for sodium-ion batteries （SIBs）.The optimization of hard carbon’s microstructure and solid electrolyte interface （SEI） property are demonstrated effective in enhancing the Na+storage capability,however,a one-step regulation strategy to achieve simultaneous multi-scale structures optimization is highly ***,we have systematically investigated the effects of boron doping on hard carbon’s microstructure and interface chemistry.A variety of structure characterizations show that appropriate amount of boron doping can increase the size of closed pores via rearrangement of carbon layers with improved graphitization degree,which provides more Na+storage ***-situ Fourier transform infrared spectroscopy/electrochemical impedance spectroscopy （FTIR/EIS） and X-ray photoelectron spectroscopy （XPS） analysis demonstrate the presence of more BC3and less B–C–O structures that result in enhanced ion diffusion kinetics and the formation of inorganic rich and robust SEI,which leads to facilitated charge transfer and excellent rate *** a result,the hard carbon anode with optimized boron doping content exhibits enhanced rate and cycling *** general,this work unravels the critical role of boron doping in optimizing the pore structure,interface chemistry and diffusion kinetics of hard carbon,which enables rational design of sodium-ion battery anode with enhanced Na+storage performance.

关键词： X ray photoelectron spectroscopy

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni2P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin peng Yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 32-38页

作者： Younong Li Li Dan Jing peng Qidong Yang Fuqiang Yang Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Atmospheric Environment and Processes in the Boundary Layer over the Low-Latitude Plateau Region Department of Atmospheric ScienceYunnan UniversityKunmingChina

El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air *** the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further *** investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 *** results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the *** higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in *** flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through *** occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures.

关键词： Carbon variability ENSO modulation CMIP6 models

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong Li peng Ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

High-temperature-tolerant flexible supercapacitors: Gel polymer electrolytes and electrode materials

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Journal of Energy Chemistry 2025年第1期100卷 426-457页

作者： Chong peng Xinyi Huang Mingwei Zhao Shuling Liao Quanhong Yang Nianjun Yang Siyu Yu School of Chemistry & Chemical Engineering Southwest University Nanoyang Group Tianjin Key Laboratory of Advanced Carbon and Electrochemical Energy Storage School of Chemical Engineering and Technology and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin) Tianjin University Department of Chemistry & IMO-IMOMEC Hasselt University

The development of flexible supercapacitors(FSCs) capable of operating at high temperatures is crucial for expanding the application areas and operating conditions of supercapacitors. Gel polymer electrolytes and electrode materials stand as two key components that significantly impact the efficacy of hightemperature-tolerant FSCs(HT-FSCs). They should not only exhibit high electrochemical performance and excellent flexibility, but also withstand intense thermal stress. Considerable efforts have been devoted to enhancing their thermal stability while maintaining high electrochemical and mechanical performance. In this review, the fundamentals of HT-FSCs are outlined. A comprehensive overview of state-of-the-art progress and achievements in HT-FSCs, with a focus on thermally stable gel polymer electrolytes and electrode materials is provided. Finally, challenges and future perspectives regarding HT-FSCs are discussed, alongside strategies for elevating operational temperatures and *** review offers both theoretical foundations and practical guidelines for designing and manufacturing HT-FSCs, further promoting their widespread adoption across diverse fields.

关键词： Flexible supercapacitors High-temperature tolerance Gel polymer electrolytes Electrode materials