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Identification of the activity source of CO2 electroreduction by strategic catalytic site distribution in stable supramolecular structure system

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National Science Review 2021年第3期8卷 78-87页

作者： Sheng-Nan Sun Ning Li Jiang Liu Wen-Xin Ji Long-Zhang Dong Yi-Rong Wang Ya-Qian Lan Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials Jiangsu Key Laboratory of New Power BatteriesSchool of Chemistry and Materials Science Nanjing Normal University School of Chemistry and Chemical Engineering Yangzhou University State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering Ningxia University

Identification of the real catalytic site in CO;2;reduction reaction（CO;2;RR） is critical for the rational design of catalysts and the understanding of reactive *** this study,the catalytic activity of pyridine-containing materials was for the first time structurally demonstrated in CO;2;RR by crystalline supramolecular coordination compounds model *** system consists of three stable supramolecular coordination compounds（Ni-TPYP,Ni-TPYP-1 and Ni-TPP） with different numbers（4,2 and 0） of active pyridine groups（*** pyridine nitrogen atoms）.The electrocatalytic test results show that with the decrease of the number of active pyridine groups,the CO;2;RR performance is gradually reduced,mainly showing the reduction of highest FE;CO;（99.8%,83.7% and 25.6%,respectively）.The crystallographic,experimental and theoretical evidences prove that the CO;2;RR activity is more likely derived from uncoordinated pyridine nitrogen than the electrocatalytic inert metal nickel in porphyrin *** work serves as an important case study for the identification of electrocatalytic activity of pyridine-containing materials in CO;2;RR by simple supramolecular model system.

关键词： strategic catalytic site distribution supramolecular structure system active source CO2 electroreduction

3D near-surface P-wave velocity structure imaging with Distributed Acoustic Sensing and electric hammer source

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Earthquake Research Advances 2024年第3期4卷 27-33页

作者： Heting Hong Fu Yin Yuhang Lei Yulan Li Baoshan Wang Deep Space Exploration Laboratory University of Science and Technology of ChinaHefei230026China School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China Mengcheng National Geophysical Observatory University of Science and Technology of ChinaHefei230026China

Distributed Acoustic Sensing(DAS) is an emerging technique for ultra-dense seismic observation, which provides a new method for high-resolution sub-surface seismic imaging. Recently a large number of linear DAS arrays have been used for two-dimensional S-wave near-surface imaging in urban areas. In order to explore the feasibility of three-dimensional(3D) structure imaging using a DAS array, we carried out an active source experiment at the Beijing National Earth Observatory. We deployed a 1 km optical cable in a rectangular shape, and the optical cable was recast into 250 sensors with a channel spacing of 4 m. The DAS array clearly recorded the P, S and surface waves generated by a hammer source. The first-arrival P wave travel times were first picked with a ShortTerm Average/Long-Term Average(STA/LTA) method and further manually checked. The P-wave signals recorded by the DAS are consistent with those recorded by the horizontal components of short-period seismometers. At shorter source-receiver distances, the picked P-wave arrivals from the DAS recording are consistent with vertical component recordings of seismometers, but they clearly lag behind the latter at greater *** is likely due to a combination of the signal-to-noise ratio and the polarization of the incoming wave. Then,we used the Tomo DD software to invert the 3D P-wave velocity structure for the uppermost 50 m with a resolution of 10 m. The inverted P-wave velocity structures agree well with the S-wave velocity structure previously obtained through ambient noise tomography. Our study indicates the feasibility of 3D near-surface imaging with the active source and DAS array. However, the inverted absolute velocity values at large depths may be biased due to potential time shifts between the DAS recording and seismometer at large source-receiver distances.

关键词： Distributed Acoustic Sensing(DAS) Near-surface structure First-arrival travel time tomography Body wave active source

Drift Control Technology Using Wire-Suspension for the Airgun source Platform in Qilian Mountain

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Earthquake Research in China 2016年第3期30卷 464-469页

作者： Zhang Yuansheng Zou Rui Yan Wenhua Lanzhou Institute of Seismology CEA

There are several key issues in dynamic monitoring of subsurface structures,such as signal-to-noise ratio( SNR),repeatability of seismic sources and accurate measurement of velocity. Using a large volume airgun source,we constructed a high-performance active system which mainly consists of airgun excitation and signal reception. In order to reduce the platform drift from the shot position,we put forward the platform drift control technique. Experimental results show that the technique can effectively solve the problem of platform drift from the set position under fluid impact after airgun excitation. The results of this study can be a reference for repeated airgun source detection at certain excitation sites.

关键词： active source large volume airgun Platform drift Repeatability

The source and Observation System of Binchuan Earthquake Signal Transmitting Seismic Station and Its Preliminary Observation Results

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Earthquake Research in China 2016年第3期30卷 316-325页

作者： Wang Bin Li Xiaobin Liu Zifeng Yang Jun Yang Runhai Wang Baoshan Yang Wei Earthquake Administration of Yunnan Province Kunming 650224 China Institute of Geophysics CEA Beijing 100051 China

This paper summarizes the basic situation of the Binchuan Transmitting Seismic Station and the geophysical observations of the area where it is located,with a focus on the constitution of the observation system of the transmitting seismic station,the excitation characteristics and propagation distance of signals excited by the airgun source in the reservoir and well. The paper also summarizes and discusses on the results of the observations and problems encountered since the Transmitting Seismic Station was ***,this paper proposes the main research to be carried out on the basis of the project aims.

关键词： Transmitting Seismic Station active source Observation system