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Chinese Chemical Letters 2023年第12期34卷 177-182页

作者： Runzhi Sun xiuqing song Shijie Wang Xiaokun Zhang Hong Yan Yeming Wang Faculty of Environment and Life Beijing University of TechnologyBejing 100124China Large-scale Instruments and Equipments Sharing Platform Beijing University of TechnologyBeijing 100124China Beijing Tide Pharmaceutical Co. Ltd.Beijing 100176China

A photocycloaddition reaction of ethyl 1,4-diaryl-1,4-dihydropyridine-3-carboxylate for the construction of 3,9-diazatetraasteranes(Pr)and 3,9-diazatetracyclododecanes(P2)is reported for the first *** types of reaction product clearly differ with solvent,regardless of the irradiation *** difference in Pi and P2 lies in the second step of the intramolecular[2+2]*** order to further investigate this phenomenon and gain a deeper understanding of the photochemical behavior of 1,4-dihydropyridines,DFT and TDDFT theoretical calculations are *** results provide a good explanation for the formation of 3,9-diazatetraasteranes and 3,9-diazatetracyclododecanes.

关键词： 1,4-Dihydropyridine Photocycloaddition Theoretical investigation 3,9-Diazatetracyclododecanes

New di-spirocyclic labdane diterpenoids from the aerial parts of Leonurus japonicus

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Chinese Journal of Natural Medicines 2023年第7期21卷 551-560页

作者： CAO Xinxin WANG Xinxin ZHANG Yu XU Defeng song xiuqing YU Jinhai BAO Jie ZHANG Junsheng ZHANG Hua School of Biological Science and Technology University of JinanJinan 250022China

Phytochemical investigation on the ethanol extract of a well-known medicinal herb Leonurus japonicus,led to the separation of 18 labdane type diterpenoids(1-18).Through comprehensive spectroscopic analyses and quantum chemical calculations,these compounds were structurally characterized as six new interesting 5,5,5-di-spirocyclic ones(1-6),two new(7 and 8)and six known(13-18)interesting 6,5,5-di-spirocyclic ones,a new rare 14,15-dinor derivative(9),and three new ones incorporating a y-lactone unit(10-12).An in vitro neuroprotective assay in RSC96 cells revealed that compounds 7 and 12 exhibited neuroprotective activity in a concentration-dependent way,comparable to the reference drug N-acetylcysteine.

关键词： Leonurus japonicus Labdane Diterpenoid Neuroprotective activity

Organocatalytic Stereoselective Synthesis of 3-Alkyl-3-hydroxy-2-oxindoles Catalyzed by Novel Water-compatible Axially Unfixed Biaryl-based Bifunctional Organocatalysts

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Chinese Journal of Chemistry 2014年第5期32卷 417-428页

作者： Hongwu Zhao Wei Meng Zhao Yang Ting Tian Zhihui Sheng Hailong Li xiuqing song Yutong Zhang Sen Yang Bo Li College of Life Science and Bio-engineering Beijing University of TechnologyBeijing 100124China

In this work,six novel axially unfixed biaryl-based water-compatible bifunctional organocatalysts were de-signed and synthesized for the organocatalytic access to a variety of 3-alkyl-3-hydroxy-2-oxindole derivatives via aldol reactions in *** by 5a,the direct aldol reactions of isatins with enolisable ketones under-went readily in water,furnishing the structurally diverse 3-alkyl-3-hydroxy-2-oxindoles in various stereoselectivi-ties(up to>99%dr and>99%ee).Moreover,a plausible transition state of the conducted aldol reactions was hy-pothesized to shed light on the observed stereoselectivities of the obtained 3-alkyl-3-hydroxy-2-oxindoles.

关键词： organocatalysis 3-alkyl-3-hydroxy-2-oxindole water-compatibility bifunctionality

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沂沭断裂带及其邻区地壳P波层析成像研究

地学前缘 2023年第2期30卷 272-281页

作者：崔鑫宋秀青石耀霖殷海涛朱元清董腾超山东省地震局山东济南250014 中国地震局地球物理研究所北京100081 上海市地震局上海200062 上海佘山地球物理国家野外科学观测研究站上海201602 中国科学院大学北京100049

沂沭断裂带是华北克拉通东部的重要断裂带,历史上发生过8(1/2)级强震,区域速度模型研究可以提升地震震动图精度以及地震烈度速报的准确性,有助于防御未来的巨震,降低震害损失。本文搜集了沂沭断裂带及其邻近区域2008—2020年的数字地震... 详细信息

沂沭断裂带是华北克拉通东部的重要断裂带,历史上发生过8(1/2)级强震,区域速度模型研究可以提升地震震动图精度以及地震烈度速报的准确性,有助于防御未来的巨震,降低震害损失。本文搜集了沂沭断裂带及其邻近区域2008—2020年的数字地震波数据,经过数据降丛集化、走时数据正态分布筛选等处理得到了地震事件震中参数和走时震相数据。基于FMTOMO方法,反演得到了沂沭断裂带地壳三维速度结构。反演结果显示,在近地表地层,速度分布特征与地表地质构造单元存在密切联系,褶皱带和基岩出露区域常常呈现高速速度分布,含较厚土层的凹陷或海域区域则一般呈现低速速度分布;在中地壳地层,速度分布特征与地震活动性有密切的联系,地震震中往往密集分布于高速和低速的过渡区域。在莫霍面深度,沂沭带的速度分布呈现了分段性差异特征,且两侧的速度分布存在差异。这可能意味着断裂带深达地幔的现象。且在沂沭带中南段区域,存在高速速度分布特征,这可能与区域地幔物质上涌有关,也可能构成强震的孕震背景。郯城区域从地表至地幔顶部均显示高速速度异常,该区域会积累高应力,可能发生8级以上地震,推测其复发周期应该很长。

关键词：山东沂沭带 P波层析成像

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Study on the Precise Location of the Xinjiang Yutian M_S7.3 Earthquake

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Earthquake Research in China 2015年第1期29卷 57-67页

作者： Zhan Xiaoyan song xiuqing Chen Xiangjun Wang Jun Miao Fajun Liu Shuangqing Zhu Yuanqing Earthquake Administration of Jiangsu Province Earthquake Administration of Shanghai Municipality Earthquake Administration of Xinjiang Uygur Autonomous Region Earthquake Administration of Tianjin Municipality

The seismic waveform of the Yutian Ms7. 3 earthquake, Xinjiang on February 12, 2014 was recorded clearly and completely by the Digital Seismic Networks of Xinjiang, Qinghai, Tibet, and Xinjiang Hotan array, so the method of joint location by regional seismic network and seismic array can be used to accurately determine the earthquake source location. The following technologies were used in the process of location：（ 1 ） We selected seismic stations equally located around the epicenter of the Ms 7. 3 earthquake with an average interval of about 15 degrees in the initial location. （2） The recording waveforms of Yutian seismic station were rotated to the radial and tangential directions to precisely obtain the arrival time of S-waves to determine the epicentral distance. （ 3） The velocity model was used in the determination of location of the epicenter, based on the historical records of earthquakes in the area within a radius of 1.0 ° from the source as the center, and the velocity model is obtained after re-fitting and calibration. （4） Based on the waveform records of the Hotan seismic array, the method of waveform beaming was used to determine the azimuths and perform the correction of the epicenter location with these azimuths. （5） The deterministic method was used to measure the source depth. Finally, it is concluded that the Yutian Ms 7. 3 main shock hypocenter location is 36. 197°N, 82. 467°E, focal depth 12km and original time 17：19：48. 2 μm. February 12, 2014.

关键词： Hypocentral location Digital seismic network Seismic array

Study on the Recurrence Probability of Strong Earthquakes of Faults

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Earthquake Research in China 2014年第2期28卷 152-163页

作者： Zhu Yuanqing Xie Chaodi song xiuqing Qin Haowen Earthquake Administration of Shanghai Municipality Department of Geophysics Yunnan University

Based on the physical model of Brownian passage time,the probabilities of recurrence of strong earthquakes on the major active faults in China are calculated in different predictive time spans,based mainly on the analysis of the earthquake preparation process before a strong earthquake occurs. Furthermore,the seismic risks on active faults are studied. The results show that the earthquake probabilities on the Xianshuihe fault,the Altyn Tagh fault,the east Kunlun fault and Xiaojiang fault are significantly greater than other faults in the Chinese mainland,which indicates that the level of stress accumulation on these faults are higher than on other faults. Therefore,these faults may have a seismic risk for strong earthquake in future.

关键词： Seismic risk Brownian passage time model Conditional probability Fault Earthquake recurrence

Focal Depth Determination of the 2014 Yutian M_S7.3 Earthquake Sequence,Xinjiang

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Earthquake Research in China 2014年第4期28卷 448-461页

作者： song xiuqing Miao Fajun Liu Shuangqing Chen Xiangjun Wang Jun Zhu Yuanqing Earthquake Administration of Shanghai Municipality Earthquake Administration of Jiangsu Province Earthquake Administration of Tianjin Municipality Earthquake Administration of Xinjiang Uygur Autonomous Region

An M_S7.3 earthquake occurred on February 12,2014 in Yutian County,Xinjiang Uygur Autonomous Region,which was followed by a series of aftershocks. This paper calculates the depth of the M_S7.3 earthquake sequence by using the deterministic approach with the seismic phase data from the catalog database of the China Earthquake Networks Center,combined with original seismic wave records from the Digital Seismic Network Center of the Earthquake Administration of Xinjiang Uygur Autonomous Region.

关键词： Focal depth Crustal velocity model Seismic sequence PTD method

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特大断面硬岩隧道爆破参数的选用

路基工程 2008年第5期 76-77页

作者：宋秀清陕西铁路工程职业技术学院陕西渭南714000

以武广客运专线鹰嘴山隧道为例,论述了特大断面硬岩隧道爆破中影响爆破效果的主要因素;重点介绍了掏槽眼和光面爆破的参数选择。

关键词：中硬岩特大断面掏槽眼光面爆破参数

用PTD方法测定2017年精河M_S6.6地震序列的深度

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中国地震 2017年第4期33卷 694-702页

作者：宋秀青上海市地震局上海市兰溪路87号200062

2017年8月9日精河发生M_S6.6地震,随后发生一系列余震。本文采用PTD方法和新疆测震台网分析的震相数据,基于新疆"2015地壳速度模型",计算了该地震序列的震源深度,得到M_S6.6主震震源深度约为14km,M_S≥2.5余震深度为9~18km。所有震相数... 详细信息

2017年8月9日精河发生M_S6.6地震,随后发生一系列余震。本文采用PTD方法和新疆测震台网分析的震相数据,基于新疆"2015地壳速度模型",计算了该地震序列的震源深度,得到M_S6.6主震震源深度约为14km,M_S≥2.5余震深度为9~18km。所有震相数据来自中国地震台网中心编目数据库。

关键词： PTD方法震源深度地壳速度模型精河MS6.6地震

Study on the Crustal Velocity Model of Xinjiang and Its Subareas

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Earthquake Research in China 2014年第4期28卷 436-447页

作者： Chen Xiangjun Shangguan Wenming song xiuqing Wang Jun Liu Shuangqing Miao Fajun Zhu Yuanqing Earthquake Administration of Xinjiang Uygur Autonomous Region Earthquake Administration of Shanghai Municipality Earthquake Administration of Jiangsu Province Earthquake Administration of Tianjin Municipality

In this paper,we firstly analyze the "3,400 travel time table "used for a long time in Xinjiang Seismological Network to obtain the velocity structure models in accord with the table by fitting. Then we fit the velocity of all seismic phases recorded in Xinjiang region in January 2009 ~ December 2013. Simulation analysis is done on the reliability and stability of the velocities,and a concept is proposed for building subarea crustal velocity models according to partitioning of seismic cluster regions. The crustal velocity model suitable for the Yutian area is fitted with the data of all phases of seismic events within a radius of 1°around the 2014 Yutian M_S7.3 earthquake since January 2009,and the model is applied to the relocation of the Yutian M_S7.3 earthquake and determination of focal depths of the earthquake sequence.

关键词： 3,400 travel time table Subarea crustal velocity model Yutian Ms7.3earthquake