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经导管主动脉瓣置换术后急性脑梗死早期识别并成功取栓一例

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中国循环杂志 2024年第8期39卷 813-815页

作者：苑飞李强刘新民王力锋姚晶罗太阳姜正明宋光远首都医科大学附属北京安贞医院瓣膜性心脏病介入治疗中心北京100029

经导管主动脉瓣置换术(TAVR)是指南推荐重度症状性主动脉瓣狭窄的重要手段之一。急性脑梗死是TAVR术后的严重并发症,显著影响患者预后和生活质量。溶栓和机械取栓是指南推荐的治疗急性脑梗死的标准方案,但其在TAVR患者的有效性和安全性... 详细信息

经导管主动脉瓣置换术(TAVR)是指南推荐重度症状性主动脉瓣狭窄的重要手段之一。急性脑梗死是TAVR术后的严重并发症,显著影响患者预后和生活质量。溶栓和机械取栓是指南推荐的治疗急性脑梗死的标准方案,但其在TAVR患者的有效性和安全性证据有限。本文报道一例TAVR术后脑梗死患者,接受了急诊脑血管造影并成功经导管取栓。

关键词：经导管主动脉瓣置换术脑梗死脑血管造影经皮颅内动脉取栓术

Numerical simulation on the multiphase flow and reoxidation of the molten steel in a two-strand tundish during ladle change

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1540-1553页

作者： Jingcheng wang Zhentong Liu Wei Chen Hongliang Chen lifeng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China School of Materials Science and Engineering Tianjin UniversityTianjin 300350China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

A 3D mathematical model was proposed to investigate the molten steel–slag–air multiphase flow in a two-strand slab continuous casting(CC)tundish during ladle *** study focused on the exposure of the molten steel and the subsequent reoxidation *** exposure of the molten steel was calculated using the coupled realizable k–εmodel and volume of fluid(VOF)*** diffusion of dissolved oxygen was determined by solving the user-defined scalar(UDS)***,the user-defined function(UDF)was used to describe the source term in the UDS equation and determine the oxidation rate and oxidation *** effect of the refilling speed on the molten steel exposure and dissolved oxygen content was also *** the refilling speed during ladle change reduced the refilling time and the exposure duration of the molten ***,the elevated refilling speed enlarged the slag eyes and increased the average dissolved oxygen content within the tundish,thereby exacerbating the reoxidation *** addition,the time required for the molten steel with a high dissolved oxygen content to exit the tundish varied with the refilling *** the inlet speed was 3.0 m·s^(-1)during ladle change,the molten steel with a high dissolved oxygen content exited the outlet in a short period,reaching a maximum dissolved oxygen content of 0.000525wt%.Conversely,when the inlet speed was 1.8 m·s^(-1),the maximum dissolved oxygen content was 0.000382wt%.The refilling speed during the ladle change process must be appropriately decreased to minimize reoxidation effects and enhance the steel product quality.

关键词： tundish ladle change reoxidation multiphase flow numerical simulation

Fluorine-induced dual defects in NiP_(2) anode with robust sodium storage performance

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Nano Research 2022年第3期15卷 2147-2156页

作者： Liang Wu lifeng wang Xiaolong Cheng Mingze Ma Ying Wu Xiaojun Wu Hengpan Yang Yan Yu Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Hefei National Laboratory for Physical Sciences at the Microscale Department of Materials Science and EngineeringCAS Key Laboratory of Materials for Energy ConversionUniversity of Science and Technology of ChinaHefei 230026China

Metal phosphides have shown great application potential as anode for sodium-ion batteries(NIBs)owing to high theoretical capacity,suitable operation voltage and abundant ***,the application of NiP_(2) anode is severely impeded by low practical capacity and fast capacity decay due to the huge volume variation and low reactivity of internal phosphorus(P)component towards Na^(+).Herein,electronic structure modulation of NiP_(2) via heteroatoms doping and introducing vacancies defects to enhance Na+adsorption sites and diffusion kinetics is successfully *** as-synthesized three-dimensional(3D)bicontinuous carbon matrix decorated with well-dispersed fluorine(F)-doped NiP_(2) nanoparticles(F-NiP_(2)@carbon nanosheets)delivers a high reversible capacity(585 mAh·g^(−1) at 0.1 A·g^(−1))and excellent long cycling stability(244 mAh·g^(−1) over 1,000 cycles at 2 A·g^(−1))when tested as anode in *** functional theory(DFT)calculations reveal that F doping in NiP_(2) induces the formation of P vacancies with increased Na+adsorption energy and accelerates the alloying of internal P *** F-NiP_(2)@carbon nanosheets//Na_(3)V_(2)(PO_(4))_(3) full cell is evaluated showing stable long cycling *** heteroatoms doping-induced dual defects strategy opens up a new way of metal phosphides for sodium storage.

关键词： NiP_(2) electronic structure modulation F doping P vacancies dual defects sodium-ion batteries

广西-东盟跨境农产品供应链管理模式及绩效评价研究

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全国流通经济 2024年第17期 16-20页

作者：王力锋姚源果范永军刘抗英百色学院广西百色533000 百色市交通运输综合行政执法支队广西百色533000

随着“一带一路”倡议的提出,我国的跨境贸易得到了进一步发展,其中,农产品贸易为顺应“双循环”发展趋势,可以将国内与国外“两种资源、两个市场”进行充分利用,但农产品跨境贸易的供应链涉及环节多、覆盖范围广,呈现出较为复杂的特质... 详细信息

随着“一带一路”倡议的提出,我国的跨境贸易得到了进一步发展,其中,农产品贸易为顺应“双循环”发展趋势,可以将国内与国外“两种资源、两个市场”进行充分利用,但农产品跨境贸易的供应链涉及环节多、覆盖范围广,呈现出较为复杂的特质,为实现农产品跨境贸易的可持续发展,开展广西-东盟跨境农产品供应链管理模式及绩效评价的实证研究。本文先分析广西-东盟跨境农产品供应链管理模式,按照农产品跨境物流以及需求的重要性,设计广西-东盟跨境农产品供应链绩效评价模型,后通过评价指标的选择规则,在目标层、准则层的基础上设定评价指标,分别通过主成分分析法评价各个指标的得分,以此获取广西-东盟跨境农产品供应链绩效的评价等级,完成绩效的评价实证分析。实证分析结果如下:广西-东盟跨境贸易的物流体系逐渐完善,跨境贸易的交货及时性和准确性不断提高,跨境农产品的质量逐渐增强,跨境贸易的信息交流愈发透明化,以此提高了消费者的满意程度、增加了企业的收益、减少了农产品贸易的通关时间和成品、加强了广西与东盟各国之间的贸易合作紧密度。

关键词：贸易合作跨境农产品供应链管理模式实证分析贸易绩效

Carrier-envelope phase passively stabilized near-infrared laser pulses from a dual-frequency pumped noncollinear optical parametric amplifier

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Chinese Science Bulletin 2014年第10期59卷 1045-1048页

作者： Shuyan Guo Weijun Ling Hao Teng Wei Zhang lifeng wang Zhiyi Wei Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Department of Physics Tianshui Normal University

By inversing the signal and idler in a two-stage noncollinear optical parametric amplifier which is,respectively,pumped by the second harmonic and fundamental wave of femtosecond Ti:sapphire laser at repetition rate of1 kHz,the carrier-envelope phase(CEP)passively stabilized pulses with a tunable wavelength from 1.1 to 1.6 lm are obtained with maximum energy of 95 lJ at 1.3 lm under the pump energy of 500 *** CEP jitter of pulses is 108 mrad measured by an f-2f *** work demonstrates a new way to efficiently generate tunable near-infrared femtosecond laser pulses with self-stabilized CEP.

关键词： Noncollinear optical parametricamplifier Femtosecond laser Carrier-envelopephase CEP jitter

Multi-functional SiC/Al Composites for Aerospace Applications

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Chinese Journal of Aeronautics 2008年第6期21卷 578-584页

作者： Cui Yan wang lifeng Ren Jianyue National Key Laboratory of Advanced Composites Beo'ing Institute of Aeronautical Materials Beijing 100095 China Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China

Multi-functional Al-matrix composites with high volume fraction （55%-57%） of SiC particles are produced with the new pressureless infiltration fabrication technology. X-ray detection and microscopic observation display the composites which are macroscopically homogeneous without porosity. The investigation further reveals that the SiC/Al composites possess low density （2.94 g/cm^3）, high elastic modulus （220 GPa）, prominent thermal management function as a result of low coefficient of thermal expansion （8 × 10^4 K^-1） and high thermal conductivity （235 W/（m.K）） as well as unique preventability of resonance vibration. By adopting a series of developed techniques, the multi-functional SiC/Al composites have managed to be made into near-net-shape parts. Many kinds of precision components of space-based optomechanical structures and airborne optoelectronic platform have been turned out. Of them, several typical products are being under test in practices.

关键词： composites multi-function infiltration SiC aluminum aerospace applications

Electromagnetic anomaly before earthquakes measured by electromagnetic experiments

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Earthquake Science 2009年第4期22卷 395-402页

作者： Guoze Zhao Yan Zhan lifeng wang Jijun wang Ji Tang Qibin Xiao Xiaobin Chen Institute of Geology China Earthquake Administration Beijing 100029 China

Three experiments are carried out for earthquake monitoring using electromagnetic （EM） methods in recent years. Some earthquakes occurred in chance of the measurement time period for each experiment and the anomalies were recorded before the shocks. The observation at a site 20 km away from the epicenter of Zhangbei Ms6.2 earthquake in 1998 shows that the apparent resistivity decreases in the strike direction before and/or during the earthquake and the resistivity increases in the decline direction. This anomalous variation in apparent resistivity accounts for about 20%. The apparent resistivities at a site in the epicentral area decrease in the strike and decline directions before and/or during the earthquake and increase after shocks. The experiments using artificial electromagnetic signals with super low frequency carried out in 1999 show that the resolution and stability of electric and magnetic spectra are improved. The spectra of electric and magnetic fields and apparent resistivity at the Baodi station began to anomalously change two days before the Qian＇an earthquake with 120 km distant to the station. The anomalous variation of electric and magnetic spectra is about twice as great as normal variation and the apparent resistivity changes by about 20%. The measurements in active seismic area of Yunnan province in the year 2005 indicate that the electric and magnetic spectra anomalously change by one order before the Taoyuan earthquake about 100 km away from the observatories. But the measurements at the sites in Beijing area 2 000 km away from the epicenter do not show any anomaly.

关键词： electromagnetic anomaly apparent resistivity artificial SLF method EM experiment magnctotellurics

Integration of homogeneous and heterogeneous nucleation growth via 3D alloy framework for stable Na/K metal anode

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eScience 2021年第1期1卷 75-82页

作者： Shufen Ye lifeng wang Fanfan Liu Pengcheng Shi Yan Yu Hefei National Laboratory for Physical Sciences at the Microscale Department of Materials Science and EngineeringNational Synchrotron Radiation LaboratoryCAS Key Laboratory of Materials for Energy ConversionUniversity of Science and Technology of China.HefeiAnhui 230026China School of Materials and Energy Guangdong University of TechnologyGuangzhouGuangdong510006China

Sodium/Potassium(Na/K)metal anodes have been considered as the promising anodes for next-generation Na/K secondary batteries owing to their ultrahigh specific capacity,low redox potential and low ***,their practical application is still hampered due to unstable solid electrolyte interphase,infinite volume change,and dendrite ***,we design a 3D-Na_(3)Bi/3D-K_(3)Bi alloy host which enables the homogeneous and heterogeneous nucleation growth of Na/K *** unique structure with periodic alternating of electron and ion conductivity improves the mass transfer kinetics and prevents the volume expansion during ***,the sodiophilicity of Na_(3)Bi/potassiophilicity of K_(3)Bi framework can avoid dendritic *** lifespans over 700 h with 1 mAh cm^(−2)for 3D-Na_(3)Bi@Na electrode and about 450 h with 1 mAh cm^(−2)for 3D-K_(3)Bi@K electrode are achieved,respectively.3D-Na_(3)Bi@Na||Na_(3)V_(2)(PO_(4))3 full battery shows sustainable cycle performance over 400 *** design provides a simple but effective approach for achieving safety of sodium/potassium metal anodes.

关键词： Na/K metal anode 3D host structure Homogeneous nucleation Heterogeneous nucleation Na_(3)Bi/K_(3)Bi

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《重订医门普度温疫论》之补法特色探颐

中国中医基础医学杂志 2024年第3期30卷 375-378页

作者：刘正中王利锋徐方易苏颖长春中医药大学长春130117

《重订医门普度温疫论》为明代吴有性原撰,清代孔以立、龚绍林评注,清代李砚庄重订于清道光十二年。该著较为全面地阐述了温疫之病因、病机、症状及治法,其中,吴有性、孔以立及龚绍林对于各种温疫伴随虚证的辨证论治之论述颇具特点,文... 详细信息

《重订医门普度温疫论》为明代吴有性原撰,清代孔以立、龚绍林评注,清代李砚庄重订于清道光十二年。该著较为全面地阐述了温疫之病因、病机、症状及治法,其中,吴有性、孔以立及龚绍林对于各种温疫伴随虚证的辨证论治之论述颇具特点,文中强调了逐邪固然重要,补虚亦不可忽视的温疫治疗原则。本文从论温疫扶正总纲、论温疫正伤成因与治法、述温疫妄补之危害三个方面对《重订医门普度温疫论》之补法特色予以阐述,对于现今临床祛邪兼用补以治疗温疫类疾病具有指导意义。

关键词：吴有性《重订医门普度温疫论》补法