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Auto Machine Learning Assisted Preparation of Carboxylic Acid by TEMPO-Catalyzed Primary Alcohol Oxidation

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Chinese Journal of Chemistry 2023年第2期41卷 143-150页

作者： Jia Qiu Yougen Xu Shimin Su Yadong Gao Peiyuan Yu Zhixiong Ruan Kuangbiao Liao Guangdong Laboratory Animals Monitoring Institute Guangdong Provincial Key Laboratory of Laboratory AnimalsGuangzhouGuangdong 510663China Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target&Clinical Pharmacology the NMPA and State Key Laboratory of Respiratory DiseaseSchool of Pharmaceutical Sciences and the Fifth Affiliated HospitalGuangzhou Medical UniversityGuangzhouGuangdong 511436China Bioland Laboratory GuangzhouGuangdong 510005China Department of Chemistry Southern University of Science and TechnologyShenzhenGuangdong 518055China Guangzhou Laboratory GuangzhouGuangdong 510320China

Though alcohol oxidations were considered as well-established reactions,selecting productive conditions or predicting reaction yields for unseen alcohols remained as major challenges.Herein,an auto machine learning(ML)model for TEMPO-catalyzed oxida-tion of primary alcohols to the corresponding carboxylic acids is disclosed.A dataset of 3444 data,consisting of 282 primary alco-hols and 45 conditions,were generated using high-throughput experimentation(HTE).With the HTE data and 105 descriptors,a multi-label prediction was performed with AutoGluon(an open-source auto machine learning framework)and KNIME(an open-source data analytics platform).For the independent test of 240 reactions(a full matrix of 20 unseen alcohols and 12 condi-tions),AutoGluon with multi-label prediction for yield prediction(AGMP)gave excellent performance.For external test of 1308 re-actions(consisting of 84 alcohols and 45 conditions),AGMP still afforded good results with R2 as 0.767 and MAE as 4.9%.The model also revealed that the newly generated descriptor(Y/N,classification of the reaction reactivity)was the most relevant descriptor for yield prediction,offering a new perspective to integrate HTE and ML in organic synthesis.

关键词： TEMPO Oxidation Primary alcohols Carboxylic acids AutoGluon

Strain-promoted S-arylation and alkenylation of sulfinamides using arynes and cyclic alkynes

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Science China Chemistry 2024年第3期67卷 928-935页

作者： Xi Zou Boming Shen Gao-lin Li Qian Liang Yanhua Ouyang Binghe Yang Peiyuan Yu Bing Gao State Key Laboratory of Chemo/Bio-Sensing and Chemometrics College of Chemistry and Chemical EngineeringInstitute of Chemical Biology and NanomedicineHunan UniversityChangsha 410082China Department of Chemistry and Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China

The conversion of commercially available chiral sulfinamides into pharmaceutically useful chiral sulfoximines via direct SIVfunctionalization is synthetically attractive but challenging due to the competitive reaction of N-functionalization. Herein, we disclose a novel strain-release strategy to access stereospecific and chemoselective SIV-arylation and alkenylation of sulfinamides using arynes and strained cyclic alkynes. This method tolerates an unprecedented chemical diversity of functional groups attached to the nitrogen center(N-R). The origin of the high SIV-selectivity is elucidated by density functional theory calculations, suggesting a stepwise mechanism for the aryne substrates and a concerted mechanism for the cyclic alkynes.

关键词： arylation alkenylation sulfoximines sulfinamides arynes

Gradient-based optimization method for producing a contoured beam with single-fed reflector antenna

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Journal of Systems Engineering and Electronics 2019年第1期30卷 22-29页

作者： LIAN peiyuan WANG Congsi XIANG Binbin SHI yu XUE Song School of Mechano-Electronic Engineering Xidian University Xinjiang Astronomical Observation Chinese Academy of Sciences Department of Mechanical Engineering Thornton Science Park University of Chester

A gradient-based optimization method for producing a contoured beam by using a single-fed reflector antenna is presented. First, a quick and accurate pattern approximation formula based on physical optics(PO) is adopted to calculate the gradients of the directivity with respect to reflector's nodal displacements. Because the approximation formula is a linear function of nodal displacements, the gradient can be easily derived. Then, the method of the steepest descent is adopted, and an optimization iteration procedure is proposed. The iteration procedure includes two loops: an inner loop and an outer loop. In the inner loop, the gradient and pattern are calculated by matrix operation, which is very fast by using the pre-calculated data in the outer loop. In the outer loop, the ideal terms used in the inner loop to calculate the gradient and pattern are updated, and the real pattern is calculated by the PO method. Due to the high approximation accuracy, when the outer loop is performed once, the inner loop can be performed many times, which will save much time because the integration is replaced by matrix operation. In the end, a contoured beam covering the continental United States(CONUS) is designed, and simulation results show the effectiveness of the proposed algorithm.

关键词： reflector antennas single feed contoured beam gradient-based optimization method.

Chiral N-triflylphosphoramide-catalyzed asymmetric hydroamination of unactivated alkenes: a hetero-ene reaction mechanism

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Organic Chemistry Frontiers 2022年第6期9卷 1649-1661页

作者： Na Wang Li-Wen Fan Jin Zhang Qiang-Shuai Gu Jin-Shun Lin Guo-Qiang Chen Xin-yuan Liu Peiyuan Yu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518071China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Chemistry and Shenzhen Grubbs Institute Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China Academy for Advanced Interdisciplinary Studies and Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

A highly enantioselective intramolecular hydroamination reaction catalyzed by chiralN-triflylphosphoramide (NTPA) that features an exceptionally broad substrate scope of isolated unactivated alkenes was recently reported by some of us. Herein we report a detailed density functional theory(DFT) study that unveil an uncommon hetero-ene reaction mechanism for this transformation. The reaction changes from a stepwise mechanism involving discrete tertiary carbocation formation to a concertedmechanism to avoid the generation of energetically unfavorable secondary carbocation species for distinctly substituted alkene substrates. The reactivity of this reaction is primarily affected by the substituentson the internal carbon of the alkene, with the carbocation-stabilizing ones promoting the reaction. Inaddition, the reaction is also influenced by the substituents on the terminal alkene carbons: those diminishing the innate alkene polarization of the starting alkenes retard the reaction by disfavoring the formation of related transition states featuring highly polarized alkene residues. The steric effect of all thesealkene substituents was found to be largely unimportant due to the unique arrangement of the heteroene reaction complex that keeps the reacting alkene away from the sterically congested core region ofthe catalyst pocket. The lower acidity of chiral phosphoric acids than that of chiral NTPAs renders the protonated precomplex along the hetero-ene reaction pathway greatly thermodynamically disfavored. Thisindirectly results in a greater relative distortion in the corresponding transition state, which in turn causesreaction retardation. Our results demonstrate the use of intramolecular pericyclic reactions as an alternative strategy for alkene activation by chiral Brønsted acid catalysis and provide insights into the furtherdevelopment of asymmetric hydrofunctionalization of unactivated alkenes.

关键词： mechanism substituent asymmetric

Detecting geo-relation phrases from web texts for triplet extraction of geographic knowledge:a context-enhanced method

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Big Earth Data 2019年第3期3卷 297-314页

作者： peiyuan Qiu Li yu Jialiang Gao Feng Lu State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina National Science Library Chinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina The Academy of Digital China Fuzhou UniversityFuzhouChina Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application NanjingChina

As an effective organization form of geographic information,a geographic knowledge graph(GeoKG)facilitates numerous geography-related analyses and services.The completeness of triplets regarding geographic knowledge determines the quality of GeoKG,thus drawing considerable attention in the related domains.Mass unstructured geographic knowledge scattered in web texts has been regarded as a potential source for enriching the triplets in GeoKGs.The crux of triplet extraction from web texts lies in the detection of key phrases indicating the correct geo-relations between geo-entities.However,the current methods for key-phrase detection are ineffective because the sparseness of the terms in the web texts describing geo-relations results in an insufficient training corpus.In this study,an unsupervised context-enhanced method is proposed to detect geo-relation key phrases from web texts for extracting triplets.External semantic knowledge is introduced to relieve the influence of the sparseness of the georelation description terms in web texts.Specifically,the contexts of geo-entities are fused with category semantic knowledge and word semantic knowledge.Subsequently,an enhanced corpus is generated using frequency-based statistics.Finally,the geo-relation key phrases are detected from the enhanced contexts using the statistical lexical features from the enhanced corpus.Experiments are conducted with real web texts.In comparison with the well-known frequency-based methods,the proposed method improves the precision of detecting the key phrases of the geo-relation description by approximately 20%.Moreover,compared with the well-defined geo-relation properties in DBpedia,the proposed method provides quintuple key-phrases for indicating the geo-relations between geo-entities,which facilitate the generation of new triplets from web texts.

关键词： Geographic knowledge graph triplet extraction geo-entity relation keyphrase detection context enhancement

A holistic approach to aligning geospatial data with multidimensional similarity measuring

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International Journal of Digital Earth 2018年第8期11卷 845-862页

作者： Li yu peiyuan Qiu Xiliang Liu Feng Lu Bo Wan State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China National Science Library Chinese Academy of SciencesBeijingPeople’s Republic of China Fujian Collaborative Innovation Center for Big Data Applications in Governments FuzhouPeople’s Republic of China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application NanjingPeople’s Republic of China Faculty of Information Engineering China University of GeosciencesWuhanPeople’s Republic of China

Semantically aligning the heterogeneous geospatial datasets(GDs)produced by different organizations demands efficient similarity matching methods.However,the strategies employed to align the schema(concept and property)and instances are usually not reusable,and the effects of unbalanced information tend to be neglected in GD alignment.To solve this problem,a holistic approach is presented in this paper to integrally align the geospatial entities(concepts,properties and instances)simultaneously.Spatial,lexical,structural and extensional similarity metrics are designed and automatically aggregated by means of approval voting.The presented approach is validated with real geographical semantic webs,Geonames and OpenStreetMap.Compared with the well-known extensional-based aligning system,the presented approach not only considers more information involved in GD alignment,but also avoids the artificial parameter setting in metric aggregation.It reduces the dependency on specific information,and makes the alignment more robust under the unbalanced distribution of various information.

关键词： Geospatial data data alignment similarity matching semantic web

Efficient removal of tetracycline hydrochloride through novel Fe/BiOBr/Bi_(2)WO_(6) photocatalyst prepared by dual-strategy under visible-light irradiation

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Journal of Environmental Sciences 2024年第4期138卷 46-61页

作者： Guanlong yu Kai Yang Yi Yang Yifu Li Qifang Sun peiyuan Li Wenming Wang Fengming Song Tao Ling Xuejun Peng Zhi yu Shiquan Sun School of Hydraulic and Environmental Engineering Changsha University of Science&TechnologyChangsha 410114China Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province Changsha 410114China Hunan Pilot Yanghu Reclaimed Water Co. Ltd.Changsha 410208China China Railway Wuju Group the First Engineering Co. Ltd.Changsha 410117China

It is important to investigate whether combining two modification strategies has a synergistic effect on the activity of photocatalysts.In this manuscript,Fe-doped BiOBr/Bi_(2)WO_(6) heterojunctions were synthesized by a one-pot solvothermal method,and excellent photocatalytic performance was obtained for the degradation of tetracycline hydrochloride(TCH)in water without the addition of surfactant.Combining experiments and characterization,the synergistic effect between Fe ion doping and the BiOBr/Bi_(2)WO_(6) heterojunction was elucidated.The Fe/BiOBr/Bi_(2)WO_(6) composite photocatalyst had a beneficial void structure,enhanced visible light response,and could inhibit the recombination of photogenerated support well,which improved the photocatalytic activity.The presented experiments demonstrate that Fe/BiOBr/Bi_(2)WO_(6) removes 97% of TCH from aqueous solution,while pure BiOBr and Bi_(2)WO_(6) only remove 56% and 65% of TCH,respectively.Finally,the separation and transfer mechanisms of photoexcited carriers were determined in conjunction with the experimental results.This study provides a new direction for the design of efficient photocatalysts through the use of a dual co-modification strategy.

关键词： BiOBr/Bi_(2)WO_(6) Fe-doping Dual strategy Tetracycline hydrochloride Photodegradation

Recent progress of surface coating on cathode materials for high-performance lithium-ion batteries

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Journal of Energy Chemistry 2020年第4期29卷 220-235页

作者： peiyuan Guan Lu Zhou Zhenlu yu yuandong Sun yunjian Liu Feixiang Wu Yifeng Jiang Dewei Chu School of Materials Science and Engineering University of New South WalesSydney 2052Australia School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina College of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina

Lithium-ion batteries (LIB) have received substantial attention in the last 10 years,as they offer great promise as power sources that can lead to the electric vehicle (EV) revolution in the next 5 years.Since the cathode serves as a key component in LIB,its properties significantly affect the performance of the whole system.Recently,the cathode surface modification based on coating technique has been widely employed to enhance the electrochemical performances by improving the material conductivity,stabilising the physical structure of materials,as well as preventing the reactions between the electrode and electrolyte.In this work,we reviewed the present of a number of promising cathode materials for Li-ion batteries.After that,we summarized the very recent research progress focusing on the surface coating strategies,mainly including the coating materials,the coating technologies,as well as the corresponding working mechanisms for cathodes.At last,the challenges faced and future guidelines for optimizing cathode materials are discussed.In this study,we propose that the structure of cathode is a crucial factor during the selection of coating materials and technologies.

关键词： Lithium-ion battery Cathode Surface Coating Electrochemical performance

Characteristics and genesis of the Feixianguan Formation oolitic shoal reservoir, Puguang gas field, Sichuan Basin, China

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Frontiers of Earth Science 2015年第1期9卷 26-39页

作者： peiyuan CHEN Xiucheng TAN Huiting YANG Ming TANG Yiwei JIANG Xiuju JIN Yang yu State Key Laboratory of Oil and Gas Geology and Exploration Southwest Petroleum University Chengdu 610500 China School of Geoscience and Technology Southwest Petroleum University Chengdu 610500 China Research Institute of Petroleum Exploration and Development SINOPEC Zhongyuan Oilfield Company Puyang 457001 China

在在西南中国的东北四川盆的著名 Puguang gasfield 的更低的三叠纪的 Feixianguan 形成生产一座代表性的鲕状的水库，吗最大的采购水兵的 gasfield 到目前为止在中国是哪个(比 350 大的证明煤气的储备地在 2003 发现了?????????????... 详细信息

在在西南中国的东北四川盆的著名 Puguang gasfield 的更低的三叠纪的 Feixianguan 形成生产一座代表性的鲕状的水库，吗最大的采购水兵的 gasfield 到目前为止在中国是哪个(比 350 大的证明煤气的储备地在 2003 发现了??????????????楥楸湡畧湡????畐畧湡？？

关键词：飞仙关组鲕滩普光气田中国西南四川盆地水库电子显微镜观察天然气储量起源