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机车电传动 1988年第2期 14-20页

作者：胡基士连级三陈登王挺泽西南交通大学

本文介绍了一种交—直—交变频调速系统,由电流源逆变器构成的主电路简单可靠,控制系统采用CMOS数字电路构成主要逻辑电路,参数可方便地调整。实验表明,本系统能容易地实现恒力矩起动和恒功率运行。

关键词：异步电机感应电机交流电机滑差率转差率电流源逆变器变频调速系统恒转矩运行整流桥恒功率运行

Fully Coupled Simulation of Interactions Among Waves, Permeable Breakwaters and Seabeds Based on N−S Equations

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China Ocean Engineering 2021年第1期35卷 26-35页

作者： LI Yan-ting wang deng-ting SUN Tian-ting HUANG Zhe LIU Qing-jun School of Civil Engineering Tianjin UniversityTianjin 300350China Nanjing Hydraulic Research Institute Nanjing 210029China

Interstitial flows in breakwater cores and seabeds are a key consideration in coastal and marine engineering designs and have a direct impact on their structural *** this paper,a unified fully coupled model for wave−permeable breakwater−porous seabed interactions is built based on an improved N−S equation.A numerical wave flume is constructed,and numerical studies are carried out by applying the finite difference *** combination with a physical model test,the accuracy of the numerical simulation results is verified by comparing the calculated and measured values of wave height at measurement points and the seepage pressure within the breakwater and *** this basis,the characteristics of the surrounding wave field and the internal flow field of the pore structure,as well as the evolution process of the fluctuating pore water pressure inside the breakwater and seabed,are further *** spatial distribution of the maximum fluctuating pore water pressure in the breakwater is compared between two cases by considering whether the seabed is permeable,and then the effect of seabed permeability on the dynamic pore water pressure in the breakwater is *** study attempts to provide a reference for breakwater design and the protection of nearby seabeds.

关键词： wave−breakwater−seabed interaction permeable breakwater porous seabed pore water pressure finite difference method

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang Shao-Jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Bioinspired Ultrasensitive Flexible Strain Sensors for Real-Time Wireless Detection of Liquid Leakage

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NANO-MICRO LETTERS 2025年第1期17卷 1-18页

作者： Zhou, Weilong Du, Yu Chen, Yingying Zhang, Congyuan Ning, Xiaowei Xie, Heng Wu, ting Hu, Jinlian Qu, Jinping Huazhong Univ Sci & Technol Sch Chem & Chem Engn Key Lab Mat Chem Energy Convers & Storage Minist EducHubei Key Lab Mat Chem & Serv Failure Wuhan 430074 Peoples R China Huazhong Univ Sci & Technol Hubei Engn Res Ctr Biomat & Med Protect Mat Sch Chem & Chem Engn Wuhan 430074 Peoples R China Wuhan Inst Technol Sch Mat Sci & Engn Wuhan 430205 Peoples R China City Univ Hong Kong Dept Biomed Engn Hong Kong 999077 Peoples R China

Micro-extrusion compression molding and surface modification were proposed for the mass fabrication of a superhydrophobic thermoplastic polyurethane sensor (TCGS).Inspired by scorpions, TCGS features Archimedean spiral crack arrays and micropores, achieving 218.13 sensitivity at 2% strain, a 4300% increase, and over 5000 usage cycles of *** robust superhydrophobicity of TCGS improves sensitivity and stability for detecting small-scale liquid leakage, allowing precise monitoring across various sizes and compositions while providing early warnings in various scenarios. Liquid leakage of pipeline networks not only results in considerable resource wastage but also leads to environmental pollution and ecological imbalance. In response to this global issue, a bioinspired superhydrophobic thermoplastic polyurethane/carbon nanotubes/graphene nanosheets flexible strain sensor (TCGS) has been developed using a combination of micro-extrusion compression molding and surface modification for real-time wireless detection of liquid leakage. The TCGS utilizes the synergistic effects of Archimedean spiral crack arrays and micropores, which are inspired by the remarkable sensory capabilities of scorpions. This design achieves a sensitivity of 218.13 at a strain of 2%, which is an increase of 4300%. Additionally, it demonstrates exceptional durability by withstanding over 5000 usage cycles. The robust superhydrophobicity of the TCGS significantly enhances sensitivity and stability in detecting small-scale liquid leakage, enabling precise monitoring of liquid leakage across a wide range of sizes, velocities, and compositions while issuing prompt alerts. This provides critical early warnings for both industrial pipelines and potential liquid leakage scenarios in everyday life. The development and utilization of bioinspired ultrasensitive flexible strain sensors offer an innovative and effective solution for the early wireless detection of liquid leakage.

关键词： Thermoplastic polyurethane Bioinspired Cracks Liquid leakage Flexible strain sensor

双介入法治疗肝硬化并上消化道出血及脾亢的临床意义

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实用放射学杂志 2003年第9期19卷 825-827页

作者：高万勤李云东陈登庭汪雁明邓淼侯民聚河南科技大学第一附属医院放射科河南科技大学第一附属医院放射科河南洛阳471003

目的　探讨经皮经肝行胃冠状静脉、胃短静脉栓塞和部分脾动脉栓塞术 (简称双介入法 ) ,治疗肝硬化合并上消化道出血、脾功能亢进的临床意义。方法　对具有完整临床诊断资料的 18例肝硬化合并急性或反复上消化道出血及脾功能亢进的病人 ... 详细信息

目的　探讨经皮经肝行胃冠状静脉、胃短静脉栓塞和部分脾动脉栓塞术 (简称双介入法 ) ,治疗肝硬化合并上消化道出血、脾功能亢进的临床意义。方法　对具有完整临床诊断资料的 18例肝硬化合并急性或反复上消化道出血及脾功能亢进的病人 ,采取双介入法用无水酒精、弹簧钢圈、明胶海绵进行胃冠状静脉、胃短静脉及部分脾动脉栓塞 ,其中栓塞胃冠状静脉 18支、胃短静脉 11支 ,脾实质栓塞 5 0 %～ 70 %左右。结果　 18例双介入法手术均顺利完成 ,除栓塞后均有不同程度的发热和脾区疼痛持续 1周～ 1月左右外 ,无特殊并发症发生。术后随访最长 6年 ,最短 4个月 ,18例病人均无再发消化道出血 ,脾功能亢进症状全部改善。结论　双介入法治疗肝硬化合并上消化道出血、脾功能亢进 ,手术操作简便易行 ,临床效果满意 ,值得推广

关键词：肝硬化上消化道出血脾亢介入放射学

Rational modulation of fluorophosphate cathode by anionic groups to reduce the polarization behavior for fast-charging sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 509-521页

作者： Xinyuan wang Fan Zhang Xingyu Zhou Qian wang Changyu Liu Yangyang Liu Hui wang Xiaojie Liu Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry & Materials Science Northwest University

Na3V2（PO4）2O2F （VP） is recognized as a promising cathode material for sodium-ion batteries due to its stable structural framework and high specific *** functional theory （DFT） and finite element simulations show that incorporating SO42-into VP decreases its band gap,lowers the migration energy barrier,and ensures a uniform Na+concentration gradient and stress distribution during charge and discharge ***,the average Na+diffusion coefficient of Na3V2（PO4）1.95（SO4）0.05O2F（VPS-1） is roughly double that of VP,leading to enhanced rate capability (80 C,75.5 mAh g-1) and cycling stability (111.0 mAh g-1capacity after 1000 cycles at 10 C current density) for ***-1 exhibits outstanding fast-charging capabilities,achieving an 80%state of charge in just 8.1 *** assembled VPS-1//SbSn/NPC full cell demonstrated stable cycling over 200 cycles at a high 5 C current,maintaining an average coulombic efficiency of 95.35%.

关键词： Anionic group modulation Polarization behavior Fast-charging Sodium-ion battery Fluorophosphate Cathode

Study on the Set-up and Set-down Induced by Breaking Waves Over A Reef

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China Ocean Engineering 2020年第6期34卷 853-862页

作者： LIU Qing-jun wang deng-ting WEI Zhang-ping XU Hua SUN Tian-ting Nanjing Hydraulic Research Institute Nanjing 210029China College of Harbour Coastal and Offshore Engineering Hohai UniversityNanjing 210098China Key Laboratory of Port Waterway&Sedimentation Engineering of MOTNanjing 210029China Department of Physics and Physical Oceanography University of North Carolina WilmingtonWilmingtonNC 28403USA

This paper proposes an equation to calculate breaking wave induced wave set-up and set-down along reef flat. The mathematical equation was derived based on the theory of radiation stress and the conservation of wave energy. The equation is primarily determined by several physical variables including the breaking wave index, the stable wave index, the attenuation coefficient of wave energy flux, and the flow velocity in the re-stabilization zone. A series of laboratory experiments were carried out to calibrate the theoretical equations. Specifically, the breaking wave index,the stable wave index, and the velocity over the reef flat were measured in the laboratory. The attenuation coefficient of wave energy flux in our theoretical equation was determined by calibration by comparing with the laboratory measured wave height. Furthermore, it has been put forward that the velocity based on cnoidal wave theory could be used to determine the velocity over the reef flat if there is no velocity measurement available. Overall, the proposed equation can provide satisfactory prediction of wave set-up and set-down along the reef flat.

关键词： wave set-up and set-down streamwise variation breaking waves reef flat reef terrain

Atomically precise nickel-sulfur clusters for efficient electrochemical 2,5-hydroxymethylfurfural oxidation

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Nano Research 2025年第1期18卷 140-148页

作者： Fen wang Lu-Yu Liu Sha-Sha Cui ting-ting Li Xiao-Meng Yang Zhijuan Liu Yanyong wang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Nickel sulfide exhibits excellent catalytic activity in the electrochemical 2,5-hydroxymethylfurfural oxidation reaction(HMFOR).However,due to the polydispersity of nanoparticles,it is difficult to establish a clear structure-activity relationship at the atomic *** this work,we have successfully synthesized atomically precise Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)clusters(PET:2-phenylethanethiol)for ***^(2+)and S_(2)-with atomic ratio of 1:2 was mainly existed in Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)to form Ni-S *** electrochemical test results have suggested both Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)displayed outstanding electrocatalytic ability for *** Ni_(6)(PET)_(12)exhibited better electrocatalytic ability than Ni_(4)(PET)_(8)with higher current density,lower overpotential and faster reaction *** superior electrochemical ability of Ni_(6)(PET)_(12)may be due to the enhanced adsorption towards HMF molecule with strong interaction towards hydroxyl group and furan ***,it found that the Ni^(2+)species in Ni_(6)(PET)_(12)could rapidly oxidized into Ni^(3+)species,which could spontaneously capture electron and proton from HMF for *** theoretical calculation demonstrated that the Ni_(6)(PET)_(12)process lower free energy barrier than Ni_(4)(PET)_(8)to display excellent electrocatalytic *** work is of great significance for designing efficient electrocatalysts for HMFOR.

关键词： atomically precise nickel nanoclusters 2 5-hydroxymethylfurfural electro-oxidation Ni3+species

Non-coding RNAs in acute ischemic stroke:from brain to periphery

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Neural Regeneration Research 2025年第1期20卷 116-129页

作者： Shuo Li Zhaohan Xu Shiyao Zhang Huiling Sun Xiaodan Qin Lin Zhu Teng Jiang Junshan Zhou Fuling Yan Qiwen deng Department of Neurology Nanjing First HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina Department of Neurology Zhongda HospitalSchool of MedicineSoutheast UniversityNanjingJiangsu ProvinceChina General Clinical Research Center Nanjing First HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina

Acute ischemic stroke is a clinical emergency and a condition with high morbidity,mortality,and *** predictive,diagnostic,and prognostic biomarkers and effective therapeutic targets for acute ischemic stroke remain *** innovations in high-throughput gene sequencing analysis,many aberrantly expressed non-coding RNAs(ncRNAs)in the brain and peripheral blood after acute ischemic stroke have been found in clinical samples and experimental *** expressed ncRNAs in the post-stroke brain were demonstrated to play vital roles in pathological processes,leading to neuroprotection or deterioration,thus ncRNAs can serve as therapeutic targets in acute ischemic ***,distinctly expressed ncRNAs in the peripheral blood can be used as biomarkers for acute ischemic stroke prediction,diagnosis,and *** particular,ncRNAs in peripheral immune cells were recently shown to be involved in the peripheral and brain immune response after acute ischemic *** this review,we consolidate the latest progress of research into the roles of ncRNAs(microRNAs,long ncRNAs,and circular RNAs)in the pathological processes of acute ischemic stroke–induced brain damage,as well as the potential of these ncRNAs to act as biomarkers for acute ischemic stroke prediction,diagnosis,and *** from this review will provide novel ideas for the clinical application of ncRNAs in acute ischemic stroke.

关键词： acute ischemic stroke apoptosis blood–brain barrier damage circular RNAs excitatory toxicity long non-coding RNAs microRNAs neuroinflammation non-coding RNAs oxidative stress

Experimental Study on Mean Overtopping of Sloping Seawall Under Oblique Irregular Waves

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China Ocean Engineering 2017年第3期31卷 350-356页

作者： wang deng-ting JU Lie-hong ZHU Jia-ling wang Zhen SUN Tian-ting CHEN Wei-qiu Nanjing Hydraulic Research Institute Nanjing 210029 China College of Harbour Coastal and Offshore Engineering Hohai University Nanjing 210098 China

In this paper, domestic and abroad research progresses and related calculation formulae of the mean overtopping discharge are summarized. Through integral physical model experiments, the relation between the wave direction and the overtopping discharge on the top of the sloping dike is focused on and put into analysis and discussion; and a modified formula for mean overtopping discharges under oblique irregular waves is proposed. The study shows that the mean overtopping discharge generally goes down as the relative wave obliquity fl increases for a fixed measurement point and the mean overtopping discharge generally increases as the wave steepness H/L decreases （the cycle increases） for a fixed relative wave obliquity.

关键词： mean overtopping discharge oblique wave sloping dike