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Transparent cap adjusted the stent placed for stenosis after endoscopic injection of esophageal varices:A case report

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World Journal of Clinical Cases 2024年第15期12卷 2614-2620页

作者： Fu-long Zhang Jing xu Yuan-Dong Zhu Qian-Neng Wu Yan Shi Lei Fang Dan Zhou Hai Wang Chao-JunHuang Chun-Hua Zhou Qun Zhu Department of Gastroenterology Hangzhou Xixi hospitalHangzhou 310023Zhejiang ProvinceChina Department of Hepatopathy Hangzhou Xixi hospitalHangzhou 310023Zhejiang ProvinceChina

BACKGROUND The stent embedded in the esophageal mucosa is one of the complications after stenting for esophageal *** present a case of stent adjustment with the aid of a transparent cap after endoscopic injection of an esophageal varices *** SUMMARY A 61-year-old male patient came to the hospital with discomfort of the chest after the stent implanted for the stenosis because of endoscopic injection of esophageal *** gastroscopy was performed,and the stent embedded into the esophageal *** first,we pulled the recycling line for shrinking the stent,however,the mucosa could not be removed from the *** a forceps was performed to remove the mucosa in the stent,nevertheless,the bleeding form the mucosa was *** then,we used a transparent cap to scrape the mucosa along the stent,and the mucosa were removed successfully without *** A transparent cap helps gastroscopy to remove the mucosa embedded in the stent after endoscopic injection of the esophageal varices stent.

关键词： Stent Transparent cap Stenosis Endoscopic injection Esophageal varices Case report

黏性牛顿流体液滴撞击干燥或预湿网面的实验研究

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力学学报 2024年第1期56卷 101-111页

作者：宗绍强徐龙郝继光北京理工大学宇航学院北京100081 西安交通大学航天航空学院西安710049

液滴撞击网面现象广泛存在于自然界和一系列应用中,液滴撞网后会穿透破碎产生二次液滴或不破碎全部附着在网面上,两种情况下都会残留液体在网面而形成预湿,影响后续撞击结果,但前人研究集中于低黏性液滴撞击干燥网面,黏性牛顿流体液滴... 详细信息

液滴撞击网面现象广泛存在于自然界和一系列应用中,液滴撞网后会穿透破碎产生二次液滴或不破碎全部附着在网面上,两种情况下都会残留液体在网面而形成预湿,影响后续撞击结果,但前人研究集中于低黏性液滴撞击干燥网面,黏性牛顿流体液滴撞击干燥或预湿网面的演化与机理仍有待探索.文章采用高速阴影成像技术,研究了黏性液滴(甘油水溶液)撞击干燥和预湿网面形成液指和破碎的演化规律,考虑了网面结构尺寸、液滴黏性及撞击前网面上预湿液膜厚度对撞击结果的影响.实验结果表明,液滴撞击干燥网面后形成液指的最大长度随网孔宽度降低、液滴黏性增加而减小;液滴黏性增加、网孔宽度减小均会抑制液滴对干燥网面的完全穿透;预湿液膜高度的增加抑制液滴对网面的完全穿透,并使不完全穿透时形成液指的最大长度减小.建立了考虑液滴黏性、网孔宽度和网面预湿的液滴撞击网面后不完全穿透时形成液指的最大长度预测模型,以及出现完全穿透时的临界参数理论预测模型,模型预测结果均与实验结果吻合良好.

关键词：黏性液滴预湿网面液指二次液滴

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回波主动抑制的次级水声发射单元设计与优化

兵工学报 2024年第5期45卷 1472-1481页

作者：王文杰杨龙赵旭北京理工大学宇航学院北京100081

水下航行器的传统涂覆层主要依赖于材料更新及结构优化,难以应对低频主动声波探测。基于超磁致伸缩材料设计一款轻质、薄型、耐高压的低频宽带水声发射单元,着重分析核心部件的设计优化过程,并由PSV-400激光测振仪验证有限元仿真结果。... 详细信息

水下航行器的传统涂覆层主要依赖于材料更新及结构优化,难以应对低频主动声波探测。基于超磁致伸缩材料设计一款轻质、薄型、耐高压的低频宽带水声发射单元,着重分析核心部件的设计优化过程,并由PSV-400激光测振仪验证有限元仿真结果。对辐射面板固定方式的模态进行分析,确定主动发射单元的最优边界约束条件。与原始构型的发射单元性能进行对比发现:在水声发射保持良好指向性的前提下,基于有限元分析2000 Hz以下的最高共振频率降低超过10%;基于声振耦合分析主动发射单元在低频范围内辐射声源级最大为147.48 dB,提高4.65%;发射单元声源级高于100 dB的频率带宽超过1500 Hz,且声功率级更高。该发射单元可为后期阵列式应用于大尺度声学覆盖层提供技术支持,具有一定的学术研究价值与广阔的工程应用前景。

关键词：回波主动抑制主动发射单元超磁致伸缩材料最优边界低频宽带

A modern survey method for determining live loads based on multi-source and open-access data on the Internet

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Frontiers of Structural and Civil Engineering 2024年第8期18卷 1135-1147页

作者： Chi xu Jun CHEN Jie LI School of Civil Engineering Tongji UniversityShanghai 200092China The State Key Laboratory on Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

Sufficient survey data are required to describe the stochastic behaviors of live ***,due to manual and on-site operation required by traditional survey methods,traditional surveys face challenges like occupant resistance,high costs,and long implementation *** study proposes a new survey method to access live load data online and *** samples are acquired from multi-source,open-access and dynamically updated data on the *** change intervals,geometrical dimensions and object quantities are obtained from transaction information,building attributes and virtual reality models on real estate websites,*** object weights are collected from commodity information on e-commerce *** integration of the aforementioned data allows for the extraction of necessary statistics to describe a live load *** proposed method is applied to a live load survey in China,covering 20040 m^(2),with around 90000 samples acquired for object weights and load *** survey results reveal that about 70%−80%of the amplitude statistics are attributable to 1/6 of the total object types.

关键词： live load online survey method data acquisition data integration

Precise construction of RuPt dual single-atomic sites to optimize oxygen electrocatalytic behaviors for high-performance Zn-air batteries

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Journal of Energy Chemistry 2024年第10期97卷 520-528页

作者： Xiaolin Hu Zhenkun Wu Chaohe xu School of Science Chongqing Key Laboratory of New Energy Storage Materials and Devices Chongqing University of Technology School of Chemistry and Engineering Chongqing University College of Materials Science and Engineering Chongqing University

The development of redox bifunctional electrocatalysts with high performance,low cost,and long lifetimes is essential for achieving clean energy *** study proposed an atom capture strategy for anchoring dual single atoms（DSAs） in a zinc-zeolitic imidazolate framework（Zn-ZIF）,followed by calcination under an N2atmosphere to synthesize ruthenium-platinum DSAs supported on a nitrogendoped carbon substrate（RuPt DSAs-NC）.Theoretical calculations showed that the degree of Ru 5dxz-*O 2pxorbital hybridization was high when*O was adsorbed at the Ru site,indicating enhanced covalent hybridization of metal sites and oxygen ligands,which benefited the adsorption of intermediate *** presence of the RuPtN6active center optimized the absorption-desorption behavior of intermediates,improving the electrocatalytic performance of the oxygen reduction reaction（ORR） and the oxygen evolution reaction（DER）,RuPt DSAs-NC exhibited a 0.87 V high half-wave potential and a 268 mV low overpotential at 10 mA cm-2in an alkaline ***,rechargeable zinc-air batteries（ZABs）achieved a peak power density of 171 MW *** RuPt DSAs-NC demonstrated long-term cycling for up to 500 h with superior round-trip *** study provided an effective structural design strategy to construct DSAs active sites for enhanced electrocata lytic performance.

关键词： Atom capture Dual single atoms catalysts Oxygen evolution reaction Oxygen reduction reaction Rechargeable Zn-air batteries

Prospects for green steelmaking technology with low carbon emissions in China

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Carbon Energy 2024年第2期6卷 1-24页

作者： Zhang Fucheng Hong Lukuo xu Ying College of Metallurgy and Energy North China University of Science and TechnologyTangshanHebeiChina Hebei Iron and Steel Laboratory TangshanHebeiChina

The steel industry is a major source of CO_(2) emissions,and thus,the mitigation of carbon emissions is the most pressing challenge in this *** this paper,international environmental governance in the steel industry is reviewed,and the current state of development of low-carbon technologies is ***,low-carbon pathways for the steel industry at the current time are proposed,emphasizing prevention and treatment ***,the prospects of low-carbon technologies are explored from the perspective of transitioning the energy structure to a“carbon-electricity-hydrogen”***,steel enterprises should adopt hydrogen-rich metallurgical technologies that are compatible with current needs and process flows in the short term,based on the carbon substitution with hydrogen(prevention)and the CCU(CO_(2) capture and utilization)concepts(treatment).Additionally,the capture and utilization of CO_(2) for steelmaking,which can assist in achieving short-term emission reduction targets but is not a long-term solution,is *** conclusion,in the long term,the carbon metallurgical process should be gradually supplanted by a hydrogen-electric synergistic approach,thus transforming the energy structure of existing steelmaking processes and attaining near-zero carbon emission steelmaking technology.

关键词： carbon capture and utilization carbon emission hydrogen metallurgy low-carbon technology steel industry

Sea level rise along China coast from 1950 to 2020

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Science China Earth Sciences 2024年第3期67卷 802-810页

作者： Dapeng MU Tianhe xu Haoming YAN Institute of Space Sciences Shandong UniversityWeihai 264209China Innovation Academy for Precision Measurement Science and Technology Chinese Academy of SciencesWuhan 430071China Institute of Marine and Antarctic Science University of TasmaniaHobartTasmania 7004Australia

Global mean sea level rise has been reconstructed using tide gauges. However, long-term sea level rise along the China coast is unclear. To address this issue, a data assimilation approach is developed to reconstruct sea level rise along the China coast from 1950 to 2020 using a global distribution of tide gauges(TGs). This approach combines climate models and sea level fingerprints. The climate models provide stereodynamic sea level changes. The sea level fingerprints include increases in ocean mass due to global ice melting and changes in water storage on land. The reconstructed global mean sea level rise agrees well with previous studies. We quantify sea level rise at 20 TGs along the China coast. The results suggest that sea level rise along the China coast(1.95±0.33 mm yr^(-1)) is greater than the global mean(1.71±0.17 mm yr^(-1)). We also find that China's coastal sea level rise is more than three times faster after 1980, increasing from 0.84±0.28 mm yr^(-1)for 1950–1980 to3.12±0.21 mm yr^(-1)for 1980–2020. This finding implies a significant sea level acceleration along the China coast. Our results advance the understanding of long-term sea level changes along the China coast.

关键词： Sea level rise China coast Tide gauges Data assimilation

Application of carbon-supported single-atom catalysts for electrochemical reactions

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新型炭材料(中英文) 2024年

作者： WANG Yi-cheng MA Xiao-bo Ayeza WANG Chen-xu LI Yang YANG Cheng-long WANG Zhe-fan WANG Chao HU Chao ZHANG Ya-ting Xi'an Thermal Power Research Institute Co. Ltd. College of Chemistry and Chemical Engineering Xi'an University of Science and Technology Tsinghua Shenzhen International Graduate School Tsinghua University School of Chemical Engineering and Technology Xi'an Jiaotong University

The recent advances in carbon-supported single-atom catalysts (SACs) for electrochemical reactions are comprehensively reviewed. The development and advantages of carbon-supported SACs are briefly introduced, followed by a detailed summary of the synthesis strategies employed for various carbon-supported SACs, including vapor phase transport, high temperature pyrolysis,and wet chemical methods. Subsequently, the advanced characterization techniques for carbon-supported SACs are reviewed. The applications of carbon-supported SACs in diverse fields, such as oxygen reduction reaction, carbon dioxide reduction reaction, nitrogen reduction reaction, hydrogen evolution reaction, and oxygen evolution reaction are summarized. Special emphasis is given to the modification strategies enabling carbon-supported SACs to exhibit excellent electrocatalytic performance. Finally, the prospects and challenges associated with utilizing carbon-supported SACs for electrochemical reactions are discussed.

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Tandem asymmetric dearomatized functionalization reaction of phenols with Evans-ynamides enabled by divergent electrophiles

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Science China Chemistry 2024年

作者： Ying-Qi Zhang Gan-Lu Qian Yun Liu Jia-Hui Li Xin Hong Zhou xu Bo Zhou long-Wu Ye State Key Laboratory of Physical Chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian Province and College of Chemistry and Chemical Engineering Xiamen University Center of Chemistry for Frontier Technologies Department of Chemistry State Key Laboratory of Clean Energy Utilization Zhejiang University Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of Pharmacy Xuzhou Medical University State Key Laboratory of Elemento-Organic Chemistry Nankai University State Key Laboratory of Organometallic Chemistry Chinese Academy of Sciences

Herein, we disclose a highly regio-/chemoselective tandem asymmetric dearomatized halofunctionalization reaction of phenoltethered ynamides with diverse electrophilic halogenation sources in a catalyst-free manner for the practical and rapid assembly of a series of halogenated spirocyclic enones. Besides, the related dearomatized selenation and protonation are also achieved,affording the corresponding selenated and protonated spirocycles in high efficiency. Moreover, the enantioselectivities of these products can be perfectly induced by Evans auxiliaries (99%ees). Significantly, this protocol not only represents the first tandem asymmetric halofunctionalization reaction of phenol derivatives, but also constitutes the first asymmetric halogenation/selenation of ynamides. Theoretical calculations indicate a remote induction model of Evans chiral auxiliary-attached keteniminium.

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