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Electrochem ically Enabled Intram olecular Am inooxygenation of Alkynes v ia Am idyl Radical Cyclization

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Chinese Journal of Chemistry 2020年第4期38卷 394-398页

作者： zhong-wei hou Hai-Chao Xu State Key Laboratory of Physical Chemistry of Solid Surfaces iChEMKey Laboratory of Chemical Biology of Fujian Provinceand College of Chemistry and Chemical EngineeringXiamen UniversityXiamenFujian 361005Chino

Summary of main observation and conclusion An electrochemical synthesis of oxazol-2-ones and imidazol-2-ones has been developed via 5-exo-dig cyclization of propargylic carbamates-and ureas-derived amidyl radicals.The electrosynthesis relies on the dual function of 2,2,66-tetramethylpiperidin-1-y oxyl(TEMPO)as a redox mediator for amidyl radical formation and an oxygen atom donor.The reactions are conducted under mild conditions using a simple setup and provide convenient access to functionalized oxazol-2-ones and imidazol-2-ones from readily available materials.

关键词： materials. donor readily

Electro.chemical Synthesis of （Aza）indolines via Dehydrogenative [3＋2] Annulatnon： Application to Total Synthesis of （±）-Hinckdentme At

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Chinese Journal of Chemistry 2018年第10期36卷 909-915页

作者： zhong-wei hou Hong Yan Jin-Shuai Song Hai-Chao Xu State Key Laboratory of Physical Chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian Province iChEM and College of Chemistry and Chemical Engineering Xiamen University Xiamen Fujian 361005 China Fujian Institute of Research on Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China

An electrochemical synthesis of functionalized （aza）indolines through dehydrogenative [3＋2] annulation of arylamines with tethered alkenes has been developed. Previous reported syntheses through similar inter- and intramolecular annulation reactions required noble-metal catalysts and are mostly limited to terminal alkenes or 1,3-dienes. The electrosynthesis employs the easily available and inexpensive ferrocene as the molecular catalyst and is compatible with di-, tri- and even tetrasubstituted alkenes to construct indolines as well as the more challenging azaindolines. Employing the newly developed electrosynthesis as a key step, the total synthesis of marine alkaloid （＋）-hinckdentine A has been achieved in 12 steps （longest linear sequence） from commercially available materials.

关键词： electrochemistry indoline radical annulation hinckdentine A

Strong light–matter interactions based on excitons and the abnormal all-dielectric anapole mode with both large field enhancement and low loss

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Photonics Research 2024年第4期12卷 854-864页

作者： YAN-HUI DENG YU-wei LU hou-JIAO ZHANG zhong-HONG SHI ZHANG-KAI Zhou XUE-HUA WANG State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou 510275China Quantum Science Center of Guangdong–Hong Kong–Macao Greater Bay Area(Guangdong) Shenzhen 518045China

The room temperature strong coupling between the photonic modes of micro/nanocavities and quantum emitters(QEs) can bring about promising advantages for fundamental and applied physics.Improving the electric fields(EFs) by using plasmonic modes and reducing their losses by applying dielectric nanocavities are widely employed approaches to achieve room temperature strong coupling.However,ideal photonic modes with both large EFs and low loss have been lacking.Herein,we propose the abnormal anapole mode (AAM),showing both a strong EF enhancement of~70-fold (comparable to plasmonic modes) and a low loss of 34 meV,which is much smaller than previous records of isolated all-dielectric nanocavities.Besides realizing strong coupling,we further show that by replacing the normal anapole mode with the AAM,the lasing threshold of the AAM-coupled QEs can be reduced by one order of magnitude,implying a vital step toward on-chip integration of nanophotonic devices.

关键词： dielectric mode coupling

Theoretical study on the stability of nanobubbles and its verification in molecular dynamics simulation

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Particuology 2024年第4期87卷 99-105页

作者： Sheng Mi Chaofeng hou wei Ge School of Chemical Engineering and Technology Tianjin UniversityTianjin300072China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing.100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China

The stability of vapor nanobubbles in bulk liquid was investigated theoretically and the critical bubble size was derived from macroscale thermodynamic equations,below which the system destabilizes with sharp drop in pressure.This critical size was quantitatively verified in molecular dynamic simulation using the Lennard-Jones model of argon,where stronger attraction between the molecules at lower density is found to contribute most to the drop of system pressure and,as the Laplace pressure on the curved bubble interface fails to balance the pressure difference across the interface,the bubbles become unstable.The theoretical model could be extended to other systems where reliable equations of state and interfacial tension are available.

关键词： Nanobubble Stability Phase diagram Critical size

A novel profile modification HPF-Co gel satisfied with fractured low permeability reservoirs in high temperature and high salinity

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Petroleum Science 2024年第1期21卷 683-693页

作者： Ya-Kai Li Ji-Rui hou wei-Peng Wu Ming Qu Tuo Liang wei-Xin zhong Yu-Chen Wen Hai-Tong Sun Yi-Nuo Pan China University of Petroleum Beijing Beijing102249China PetroChina Tarim Oilfield Company Korla 841000XinjiangChina Key Laboratory of Improving Oil and Gas Recovery of Ministry of Education Northeast Petroleum University Daqing 163318HeilongjiangChina Xi'an Shiyou University Xi'an 710065ShaanxiChina Northwest Oilfield Company SINOPECUrumqi 830011XinjiangChina

Conformance control and water plugging are a widely used EOR method in mature oilfields.However,majority of conformance control and water plugging agents are unavoidable dehydrated situation in high-temperature and high-salinity low permeability reservoirs.Consequently,a novel conformance control system HPF-Co gel,based on high-temperature stabilizer(CoCl_(2)·H_(2)O,CCH)is developed.The HPF-Co bulk gel has better performances with high temperature(120℃)and high salinity(1×10^(5)mg/L).According to Sydansk coding system,the gel strength of HPF-Co with CCH is increased to code G.The dehydration rate of HPF-Co gel is 32.0%after aging for 150 d at 120℃,showing excellent thermal stability.The rheological properties of HPF gel and HPF-Co gel are also studied.The results show that the storage modulus(G′)of HPF-Co gel is always greater than that of HPF gel.The effect of CCH on the microstructure of the gel is studied.The results show that the HPF-Co gel with CCH has a denser gel network,and the diameter of the three-dimensional network skeleton is 1.5-3.5μm.After 90 d of aging,HPF-Co gel still has a good three-dimensional structure.Infrared spectroscopy results show that CCH forms coordination bonds with N and O atoms in the gel amide group,which can suppress the vibration of cross-linked sites and improve the stability at high temperature.Fractured core plugging test determines the optimized polymer gel injection strategy and injection velocity with HPF-Co bulk gel system,plugging rate exceeding 98%.Moreover,the results of subsequent waterflooding recovery can be improved by 17%.

关键词： Low permeability reservoir High-temperature resistant gel Complexation reaction Polymer gel injection strategy Plugging rate Enhanced oil recovery

First Digit Distributions of Gamma-Ray Bursts

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Research in Astronomy and Astrophysics 2024年第5期24卷 70-75页

作者： hou-Yu Lai Jun-Jie wei Purple Mountain Observatory Chinese Academy of SciencesNanjing 210023China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

The occurrence of the first significant digits from real world sources is usually not equally distributed,but is consistent with a logarithmic distribution instead,known as Benford’s law.In this work,we perform a comprehensive investigation on the first digit distributions of the duration,fluence,and energy flux of gamma-ray bursts (GRBs) for the first time.For a complete GRB sample detected by the Fermi satellite,we find that the first digits of the duration and fluence adhere to Benford’s law.However,the energy flux shows a significant departure from this law,which may be due to the fact that a considerable part of the energy flux measurements is restricted by lack of spectral information.Based on the conventional duration classification scheme,we also check if the durations and fluences of long and short GRBs (with duration T_(90)>2 s and T_(90)≤2 s,respectively) obey Benford’s law.We find that the fluences of both long and short GRBs still agree with the Benford distribution,but their durations do not follow Benford’s law.Our results hint that the long–short GRB classification scheme does not directly represent the intrinsic physical classification scheme.

关键词： (stars:)gamma-ray burst general-methods statistical-astronomical databases miscellaneous

Evolution of chemistry and selection technology for DNA-encoded library

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Acta Pharmaceutica Sinica B 2024年第2期14卷 492-516页

作者： Peixiang Ma Shuning Zhang Qianping Huang Yuang Gu Zhi Zhou wei hou wei Yi Hongtao Xu Shanghai Key Laboratory of Orthopedic Implants Department of OrthopedicsShanghai Ninth People’s HospitalShanghai Jiao Tong UniversitySchool of MedicineShanghai 200025China Shanghai Institute for Advanced Immunochemical Studies ShanghaiTech UniversityShanghai 201210China Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target&Clinical Pharmacology The NMPA and State Key Laboratory of Respiratory DiseaseGuangzhou Medical UniversityGuangzhou 511436China College of Pharmaceutical Science and Institute of Drug Development&Chemical Biology Zhejiang University of TechnologyHangzhou 310014China

DNA-encoded chemical library(DEL)links the power of amplifiable genetics and the nonself-replicating chemical phenotypes,generating a diverse chemical world.In analogy with the biological world,the DEL world can evolve by using a chemical central dogma,wherein DNA replicates using the PCR reactions to amplify the genetic codes,DNA sequencing transcripts the genetic information,and DNA-compatible synthesis translates into chemical phenotypes.Importantly,DNA-compatible synthesis is the key to expanding the DEL chemical space.Besides,the evolution-driven selection system pushes the chemicals to evolve under the selective pressure,i.e.,desired selection strategies.In this perspective,we summarized recent advances in expanding DEL synthetic toolbox and panning strategies,which will shed light on the drug discovery harnessing in vitro evolution of chemicals via DEL.

关键词： DNA-encoded library Drug discovery High-throughput selection DNA-compatible synthesis In vitro evolution Chemical central dogma

Improved forecasting via physics-guided machine learning as exemplified using“21·7”extreme rainfall event in Henan

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Science China Earth Sciences 2024年第5期67卷 1652-1674页

作者： Qi zhong Zhicha ZHANG Xiuping YAO Shaoyu hou Shenming FU Yong CAO Linguo JING China Meteorological Administration Training Center Beijing 100081China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Zhejiang Meteorological Observatory Hangzhou 310017China Hebei Provincial Weather Modification Center Shijiazhuang 050020China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China National Meteorological Center Beijing 100081China School of Computer Science Chengdu University of Information TechnologyChengdu 610225China

As a natural disaster,extreme precipitation is among the most destructive and influential,but predicting its occurrence and evolution accurately is very challenging because of its rarity and uniqueness.Taking the example of the“21·7”extreme precipitation event(17–21 July 2021)in Henan Province,this study explores the potential of using physics-guided machine learning to improve the accuracy of forecasting the intensity and location of extreme precipitation.Three physics-guided ways of embedding physical features,fusing physical model forecasts and revised loss function are used,i.e.,(1)analyzing the anomalous circulation and thermodynamical factors,(2)analyzing the multi-model forecast bias and the associated underlying reasons for it,and(3)using professional forecasting knowledge to design the loss function,and the corresponding results are used as input for machine learning to improve the forecasting accuracy.The results indicate that by learning the relationship between anomalous physical features and heavy precipitation,the forecasting of precipitation intensity is improved significantly,but the location is rarely adjusted and more false alarms appear.Possible reasons for this are as follows.The anomalous features used here mainly contain information about large-scale systems and factors which are consistent with the model precipitation deviation;moreover,the samples of extreme precipitation are sparse and so the algorithm used here is simple.However,by combining“good and different”multi models with machine learning,the advantages of each model are extracted and then the location of the precipitation center in the forecast is improved significantly.Therefore,by combining the appropriate anomalous features with multi-model fusion,an integrated improvement of the forecast of the rainfall intensity and location is achieved.Overall,this study is a novel exploration to improve the refined forecasting of heavy precipitation with extreme intensity and high variability,and provides a reference for the deep fusion of

关键词： Extreme precipitation event Refined assessment Anomalous physical features Multi-model fusion Machine learning

Small intestine angioleiomyoma as a rare cause of perforation:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2116-2121页

作者： Teng-Yuan hou wei-Juo Tzeng Pei-Hang Lee Department of General Surgery Kaohsiung Chang Gung Memorial HospitalKaohsiung 833Taiwan Department of Anatomical Pathology Kaohsiung Chang Gung Memorial HospitalKaohsiung 833Taiwan

BACKGROUND Angioleiomyoma is a rare and benign stromal tumor typically found in subcutaneous tissue.It rarely occurs in the gastrointestinal tract.Among the reported cases,the most common complication was gastrointestinal bleeding.Perforation has only been reported as a complication in the last few decades.CASE SUMMARY This case report detailed the discovery of intestinal angioleiomyoma in a 47-yearold male presenting with abdominal pain that had persisted for 3 d.After suspecting hollow organ perforation,surgical intervention involving intestinal resection and anastomosis was performed.CONCLUSION The report underscores the significance of early surgical intervention in effectively treating angioleiomyoma while emphasizing the pivotal role of timely and appropriate measures for favorable outcomes.

关键词： Angioleiomyoma Intestinal perforation Abdomen Acute Diarrhea Case report