Search Results - "Li, Jiuyuan"

Assessment of the seismic hazard in North China by combining micro-seismicity records and geodetic observations by Gao, Yuan, Qu, Wei, Zhang, Qin, Li, Jiuyuan, Li, Da, Wang, Yuhao, Hao, Ming

“…North China has suffered numerous devastating historical and recent earthquakes, causing huge loss of life and property. Therefore, it is vital to identify the…”
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Spatiotemporal Variations and Sustainability Characteristics of Groundwater Storage in North China from 2002 to 2022 Revealed by GRACE/GRACE Follow-On and Multiple Hydrologic Data by Qu, Wei, Zhang, Pufang, Chen, Peinan, Li, Jiuyuan, Gao, Yuan

“…North China (NC) is experiencing significant groundwater depletion. We used GRACE and GRACE-FO RL06 Level-2 data with Mascon data from April 2002 to July 2022…”
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Chiral Primary−Tertiary Diamine Catalysts Derived From Natural Amino Acids for syn-Aldol Reactions of Hydroxy Ketones by Li, Jiuyuan, Luo, Sanzhong, Cheng, Jin-Pei

“…A series of primary-tertiary diamine catalysts were designed and synthesized from primary natural amino acids. Application of these new chiral catalysts in…”
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Fine divided method of active tectonic blocks based on adaptive density peak clustering and improved Euler model, revealed by GNSS velocities in Southwest Japan by Qu, Wei, Wang, Jiapeng, Yang, Yinghui, Gao, Yuan, Li, Jiuyuan, Wang, Yuhao, Zhang, Qin, Hao, Ming

“…The rational division of active tectonic blocks is an important premise for distinguishing active faults, discovering hidden faults, and an in-depth…”
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Chiral Primary Amine Catalyzed Enantioselective Protonation via an Enamine Intermediate by Fu, Niankai, Zhang, Long, Li, Jiuyuan, Luo, Sanzhong, Cheng, Jin-Pei

“…Enamine protonation: A chiral diamine catalyzes an asymmetric Friedel–Crafts reaction through catalytic enantioselective protonation of an enamine. This…”
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Stepwise estimation of height change time series and two-dimensional surface deformation over mountain excavation and City construction region with TS-InSAR technique by Li, Guangrong, Zhao, Chaoying, Li, Bin, Li, Jiuyuan, Liu, Xiaojie, Lou, Jianqi, Yan, Ming, Wang, Baohang

“…•A new time-series InSAR method is proposed to stepwise estimation of height change time series and two-dimensional surface deformation.•Severe vertical…”
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Asymmetric [3+2] annulations of 1,4-di-thiane-2,5-diol and oxindole ketimines by Feng, Bo-Xu, Yang, Jin-Dong, Li, Jiuyuan, Li, Xin

“…[Display omitted] •An asymmetric [3+2] annulation of 1,4-di-thiane-2,5-diol and N-Boc ketimines was realized.•A number of chiral spiro-aminooxindole…”
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Physical Organic Study of Structure-Activity-Enantioselectivity Relationships in Asymmetric Bifunctional Thiourea Catalysis: Hints for the Design of New Organocatalysts by Li, Xin, Deng, Hui, Zhang, Bo, Li, Jiuyuan, Zhang, Long, Luo, Sanzhong, Cheng, Jin-Pei

“…Acidity effect: Correlations of pKa with catalytic activity and stereoselectivity were determined and linear free energy relationships (LFERs) were observed…”
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Highly Enantioselective Direct syn- and anti-Aldol Reactions of Dihydroxyacetones Catalyzed by Chiral Primary Amine Catalysts by Luo, Sanzhong, Xu, Hui, Zhang, Long, Li, Jiuyuan, Cheng, Jin-Pei

“…We present herein simple primary−tertiary diamine−Brønsted acid conjugates that catalyze both syn- and anti-aldol reactions of dihydroxyacetones (DHAs) with…”
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Asymmetric Supramolecular Primary Amine Catalysis in Aqueous Buffer: Connections of Selective Recognition and Asymmetric Catalysis by Hu, Shenshen, Li, Jiuyuan, Xiang, Junfeng, Pan, Jie, Luo, Sanzhong, Cheng, Jin-Pei

“…A new approach of asymmetric supramolecular catalysis has been developed by combining the supramolecular recognition of β-cyclodextrin (β-CD) and the superior…”
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Noncovalently Supported Heterogeneous Chiral Amine Catalysts for Asymmetric Direct Aldol and Michael Addition Reactions by Luo, Sanzhong, Li, Jiuyuan, Zhang, Long, Xu, Hui, Cheng, Jin-Pei

“…A new strategy for the immobilization of asymmetric organocatalysts by combining polystyrene (PS)/sulfonic acids and chiral amines in situ through acid–base…”
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Chiral Primary Amine Catalyzed Asymmetric Direct Cross-Aldol Reaction of Acetaldehyde by Hu, Shenshen, Zhang, Long, Li, Jiuyuan, Luo, Sanzhong, Cheng, Jin-Pei

“…The first primary aminocatalytic direct cross‐aldol reaction of acetaldehyde is presented. Among the various vicinal diamines screened, the L‐tert‐leucine…”
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Chiral Primary−Tertiary Diamine−Brønsted Acid Salt Catalyzed Syn-Selective Cross-Aldol Reaction of Aldehydes by Li, Jiuyuan, Fu, Niankai, Li, Xin, Luo, Sanzhong, Cheng, Jin-Pei

“…Highly syn-selective cross-aldol reaction of aldehydes has remained a challenging subject in the field of aminocatalysis. To achieve this end, chiral primary…”
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Chiral Amine−Polyoxometalate Hybrids as Highly Efficient and Recoverable Asymmetric Enamine Catalysts by Luo, Sanzhong, Li, Jiuyuan, Xu, Hui, Zhang, Long, Cheng, Jin-Pei

“…Chiral amine and polyoxometalate (POM) acids were combined to give highly efficient, stereoselective, and recoverable enamine-based catalysts. Less than 1 mol…”
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Asymmetric Retro- and Transfer-Aldol Reactions Catalyzed by a Simple Chiral Primary Amine by Luo, Sanzhong, Zhou, Pengxin, Li, Jiuyuan, Cheng, Jin-Pei

“…One stone four birds: A single chiral primary amine was found to catalyze unprecedented asymmetric retro‐aldol and transfer‐aldol reactions, leading to four…”
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Facile evolution of asymmetric organocatalysts in water assisted by surfactant Brønsted acids by Luo, Sanzhong, Xu, Hui, Li, Jiuyuan, Zhang, Long, Mi, Xueling, Zheng, Xiaoxi, Cheng, Jin-Pei

“…Simple mixing of chiral amines and surfactant Brønsted acids such as p-dodecyl benzenesulfonic acid (DBSA) leads to highly effective and selective…”
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Chiral Amine-Polyoxometalate Hybrids as Recoverable Asymmetric Enamine Catalysts under Neat and Aqueous Conditions by Li, Jiuyuan, Hu, Shenshen, Luo, Sanzhong, Cheng, Jin-Pei

“…Solid acid–chiral amine hybrids have been synthesized and explored as recyclable and reusable enamine‐type asymmetric catalysts. Simple chiral…”
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Chiral Primary Amine Catalyzed Asymmetric Epoxidation of α-Substituted Acroleins by Li, Jiuyuan, Fu, Niankai, Zhang, Long, Zhou, Pengxin, Luo, Sanzhong, Cheng, Jin-Pei

“…1,1‐Disubstituted terminal alkenes remain challenging substrates in asymmetric epoxidation reactions. In this study, chiral primary amines are shown to…”
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Asymmetric Direct Aldol Reactions of Acetoacetals Catalyzed by a Simple Chiral Primary Amine by Luo, Sanzhong, Qiao, Yupu, Zhang, Long, Li, Jiuyuan, Li, Xin, Cheng, Jin-Pei

“…An asymmetric direct aldol reaction of acetoacetals is described. Under the catalysis of a simple chiral primary amine, the direct aldol reactions of…”
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Chiral Primary Amine–Polyoxometalate Acid Hybrids as Asymmetric Recoverable Iminium‐Based Catalysts by Li, Jiuyuan, Li, Xin, Zhou, Pengxin, Zhang, Long, Luo, Sanzhong, Cheng, Jin‐Pei

“…A new strategy for the immobilization of iminium organocatalysts through the acid–base assembly of multidentate chiral primary amines and solid polyacids is…”
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