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Radical cascade cyclization for the green and simple synthesis of silylated indolo[2,1-a]isoquinoline derivatives via visible light-mediated Si–H bonds activation

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Chinese Chemical Letters 2024年第1期35卷 243-249页

作者： Zhenkai Lei Fei Xue Bin Wang Shijie Wang Yu Xia yonghong zhang Weiwei Jin Chenjiang Liu State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources Key Laboratory of Oil and Gas Fine ChemicalsMinistry of Education&Xinjiang Uygur Autonomous RegionUrumqi Key Laboratory of Green Catalysis and Synthesis TechnologyCollege of ChemistryXinjiang UniversityUrumqi 830017China College of Future Technology Institute of Materia Medic1Xinjiang UniversityUrumqi 830017China Xinjiang Uygur Autonomous Region Product Quality Supervision and Inspection Institute Urumqi 830011China

Photocatalytic and photoinduced silyl radicals cascade cyclization procedures for the green and simple preparation of fused tetracyclic skeleton silylated indolo[2,1-a]isoquinoline-6(5H)-ones from 2-aryl-N-acryloyl indoles with hydrosilanes are developed.The photocatalytic reaction is carried out with 9,10-dicyanoanthracene(DCA)as an organophotocatalyst and 3-acetoxyquinuclidine as hydrogen atom transfer(HAT)catalyst at room temperature under metal-and oxidant-free conditions.The keys to the success of photoredox-catalytic conversion include(1)the reductive quenching of DCA^(*)[E_(1/2)(*P/P^(-))=+1.97 V vs.SCE in MeCN]by 3-acetoxyquinuclidine(E_(p)=+1.22 V vs.SCE in MeCN),and(2)the thermodynamic feasibility of hydrogen atom abstraction from hydridic Si-H bond by electrophilic N^(+·).Particularly,the simple photoinduced cascade cyclization using(TMS)3SiH with 2-aryl-N-acryloyl indoles was exploited via an electron-donor-acceptor(EDA)complex under visible light irradiation.

关键词： Indolo[2,1-a]isoquinolines Silyl radicals Green photocatalytic Simple photoinduced Silylated Hydrogen atom transfer EDA complex

Electrical discharge and arc milling with automatic tracking of optimal flushing direction:A novel high-efficiency compound machining method

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Chinese Journal of Aeronautics 2024年第3期37卷 351-364页

作者： Xinlei WU yonghong LIU Pengxin zhang Liang QI Dege LI Chi MA Renjie JI College of Mechanical and Electronic Engineering China University of Petroleum(East China)Qingdao 266580China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China

The arc milling method has the advantages of high machining efficiency and low cost and is independent of the strength and hardness of machined materials.However,frequent electrode back-offs and the risk of workpiece burning may occur if erosion products are not removed promptly.In this study,it was found that the flushing method of the working medium had a significant impact on the machining performance of arc milling.Based on this,a novel highefficiency compound machining method of electrical discharge and arc milling with automatic tracking of the optimal flushing direction was proposed.An automatic tracking optimizer for external working medium injection was designed to determine the optimal external flushing direction according to the feed direction.The influence of flushing methods,working mediums,and machining parameters on the machining efficiency,tool electrode wear rate,machining error,and surface integrity of titanium alloys were investigated.The results indicated that better machining performance and environmental friendliness were achieved using the compound flushing method of outer compressed air and inner deionized water.Additionally,the automatic tracking flushing method in the opposite direction of the feed direction showed superior results compared to other directions.The material removal rate with the opposite direction injection could be increased up to 1.62 times that of the same direction,and the relative electrode wear rate could be reduced by 14.76%.This novel method has broad application prospects for machining parts with difficult-to-cut materials in aerospace and military industries.

关键词： Arc milling Dielectric Difficult-to-cut materials Electric discharge machining Erosion Material removal rate

Eco-physiological characteristics of Tetracentron sinense Oliv.saplings in response to different light intensities

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Journal of Forestry Research 2024年第3期35卷 29-44页

作者： Rong Wang Xueheng Lu Hongyan Han Xuemei zhang yonghong Ma Qinsong Liu Xiaohong Gan Key Laboratoryof Southwest Wildlife Resources Conservation Ministry of EducationChina West Normal UniversityNanchong 637009People's Republic of China Institute of Plant Adaptation and Utilization in Southwest Mountain China West Normal UniversityNanchong 637009People's Republic of China Office of the People's Government of Yuexi County Yuexi County 616650Liangshan Yi Autonomous PrefecturePeople's Republic of China

The regeneration of Tetracentron sinense Oliv.is poor in the understory and in open areas due to the charac-teristics of natural regeneration of the species on forest edges and in gaps.It is unclear whether different light intensities in various habitats affect eco-physiological characteristics of saplings and their natural regeneration.In this study,the light intensity in T.sinense habitats was simulated by artificial shading(L1:100%NS(natural sunlight)in the open;L2:50%NS in a forest gap or edge;L3:10%NS in understory)to investigate differences in morphology,leaf structure,physiology,and photosynthesis of 2-year-old sap-lings,and to analyze the mechanism of light intensity on sapling establishment.Significant differences were observed in morphology(including leaf area,and specific leaf area)under different light intensities.Compared to L1 and L3,chloroplast structure in L2 was intact.With increasing time,superoxide dismutase(SOD)and catalase(CAT)activities in L2 became gradually higher than under the other light intensities,while malondialdehyde(MDA)content was opposite.Shading decreased osmoregulation substance contents of leaves but increased chlorophyll.The results suggest that light intensities significantly affect the eco-physiological characteristics of T.sinense saplings and they would respond most favorably at intermediate levels of light by optimizing eco-physiological characteristics.Therefore,50%natural sunlight should be created to promote saplings establishment and population recovery of T.sinense during in situ conservation,including sowing mature seeds in forest edges or gaps and providing appropriate shade protection for seedlings and saplings in the open.

关键词： Chloroplast ultrastructure Eco-physiological characteristics Light intensities Sapling establishment Tetracentron sinense Oliv

Fire-retardant, anti-dripping, biodegradable and biobased polyurethane elastomers enabled by hydrogen-bonding with cellulose nanocrystals

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Nano Research 2024年第3期17卷 2186-2194页

作者： Yijiao Xue Tianchen zhang Hong Peng Zhewen Ma Meng zhang Mark Lynch Toan Dinh Zhezhe Zhou yonghong Zhou Pingan Song Institute of Chemical Industry of Forest Products Chinese Academy of Forestry(CAF)Nanjing 210042China School of Chemical Engineering The University of QueenslandBrisbaneQld 4072Australia Department of Polymer Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China School of Agriculture and Environmental Science University of Southern QueenslandToowoombaQld 4300Australia Centre for Future Materials University of Southern QueenslandToowoombaQld 4300Australia

Thermoplastic polyurethane(PU)elastomers have attracted significant attention because of their many important industrial applications.However,the creation of fire-retardant and anti-dripping PU elastomers has remained a grant challenge due to the lack of crosslinking and weak interchain interactions.Herein,we report a mechanically robust,biodegradable,fire-retardant,and anti-dripping biobased PU elastomer with excellent biodegradability using an abietic acid-based compound as hard segments and polycaprolactone diol(PCL)as soft segments,followed by physically crosslinking with cellulose nanocrystals(CNC)through dynamic hydrogen-bonding.The resultant elastomer shows the balanced mechanical and fire-retardant properties,e.g.,a tensile strength and break strain of 9.1 MPa and 560%,a self-extinguishing ability(V-0 rating in UL-94 testing),and an anti-dripping behavior.Moreover,the as-developed PU can be completely degraded in 1.0 wt.%lipase solution at 37℃ in 60 days,arising from the catalytic and wicking effect of CNC on PU chains.This work provides an innovative and versatile strategy for constructing robust,fire-retardant,anti-dripping,and biodegradable PU elastomers,which hold great promise for practical applications in electronic and automobile sectors.

关键词： polyurethane elastomers cellulose nanocrystals fire retardancy anti-dripping biodegradation

Comparative Experimental Study on Heat Transfer Characteristics of Building Exterior Surface at High and Low Altitudes

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Journal of Thermal Science 2024年第3期33卷 1119-1131页

作者： JIA yonghong GUO Shurui LI Jin GUO Lei CHENG Zhu zhang Yin YANG Hanyu LONG Enshen Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610065China MOE Key Laboratory of Deep Earth Science and Engineering College of Architecture and EnvironmentSichuan UniversityChengdu610065China

The external surface heat transfer coefficient of building envelope is one of the important parameters necessary for building energy saving design,but the basic data in high-altitude area are scarce.Therefore,the authors propose a modified measurement method based on the heat balance of a model building,and use the same model building to measure its external surface heat transfer coefficient under outdoor conditions in Chengdu city,China at an altitude of 520 m and Daocheng city at an altitude of 3750 m respectively.The results show that the total heat transfer coefficient(h_(t))of building surface in high-altitude area is reduced by 34.48%.The influence of outdoor wind speed on the convective heat transfer coefficient(h_(c))in high-altitude area is not as significant as that in low-altitude area.The fitting relation between convection heat transfer coefficient and outdoor wind speed is also obtained.Under the same heating power,the average temperature rise of indoor and outdoor air at highaltitude is 41.9%higher than that at low altitude,and the average temperature rise of inner wall is 25.8%higher than that at low altitude.It shows that high-altitude area can create a more comfortable indoor thermal environment than low-altitude area under the same energy consumption condition.It is not appropriate to use the heat transfer characteristics of the exterior surface of buildings in low-altitude area for building energy saving design and related heating equipment selection and system terminal matching design in high-altitude area.

关键词： altitude heat transfer characteristics convective heat transfer coefficient(h_(c)) radiative heat transfer coefficient(h_(r)) external building envelope

Artificial selection of the Green Revolution gene Semidwarf 1 is implicated in upland rice breeding

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Journal of Integrative Agriculture 2024年第3期23卷 769-780页

作者： Shuliang Jiao Qinyan Li Fan zhang yonghong Tao Yingzhen Yu Fan Yao Qingmao Li Fengyi Hu Liyu Huang Key Laboratory of Biology and Germplasm Innovation of Perennial Rice Ministry of Agriculture and Rural Affairs/School of AgricultureYunnan UniversityKunming 650091China State Key Laboratory of Crop Gene Resources and Breeding Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China Wenshan Academy of Agricultural Sciences Wenshan 663000China

Semidwarf breeding has boosted crop production and is a well-known outcome from the first Green Revolution. The Green Revolution gene Semidwarf 1(SD1), which modulates gibberellic acid(GA) biosynthesis, plays a principal role in determining rice plant height. Mutations in SD1 reduce rice plant height and promote lodging resistance and fertilizer tolerance to increase grain production. The plant height mediated by SD1 also favors grain yield under certain conditions. However, it is not yet known whether the function of SD1 in upland rice promotes adaptation and grain production. In this study, the plant height and grain yield of irrigated and upland rice were comparatively analyzed under paddy and dryland conditions. In response to dryland environments, rice requires a reduction in plant height to cope with water deficits. Upland rice accessions had greater plant heights than their irrigated counterparts under both paddy and dryland conditions, and appropriately reducing plant height could improve adaptability to dryland environments and maintain high grain yield formation. Moreover, upland rice cultivars with thicker stem diameters had stronger lodging resistance, which addresses the lodging problem. Knockout of SD1 in the upland rice cultivar IRAT104 reduced the plant height and grain yield, demonstrating that the adjustment of plant height mediated by SD1 could increase grain production in dryland fields. In addition, an SD1 genetic diversity analysis verified that haplotype variation causes phenotypic variation in plant height. During the breeding history of rice, SD1 allelic mutations were selected from landraces to improve the grain yield of irrigated rice cultivars, and this selection was accompanied by a reduction in plant height. Thus, five known mutant alleles were analyzed to verify that functional SD1 is required for upland rice production. All these results suggest that SD1 might have undergone artificial positive selection in upland rice, which provides further insights concerning greater plant heigh

关键词： Green Revolution Semidwarf 1 high-yield breeding upland rice plant height

Unique double-layer solid electrolyte interphase formed with fluorinated ether-based electrolytes for high-voltage lithium metal batteries

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Journal of Energy Chemistry 2024年第1期88卷 532-542,I0012页

作者： Ruo Wang Jiawei Li Bing Han Qingrong Wang Ruohong Ke Tong zhang Xiaohu Ao Guangzhao zhang Zhongbo Liu Yunxian Qian Fangfang Pan Iseult Lynch Jun Wang yonghong Deng Department of Materials Science&Engineering School of Innovation and EntrepreneurshipSouthern University of Science and TechnologyShenzhen 518055GuangdongChina School of Geography Earth and Environmental SciencesUniversity of BirminghamEdgbastonBirmingham B152TTUK Key Laboratory of Marine Environmental Corrosion and Bio-Fouling Institute of OceanologyChinese Academy of SciencesQingdao 266071ShandongChina Shenzhen CAPCHEM Technology Co. Ltd.Shenzhen 518118GuangdongChina CALB Group Co. Ltd.Changzhou 213200JiangsuChina

Li metal batteries using high-voltage layered oxides cathodes are of particular interest due to their high energy density.However,they suffer from short lifespan and extreme safety concerns,which are attributed to the degradation of layered oxides and the decomposition of electrolyte at high voltage,as well as the high reactivity of metallic Li.The key is the development of stable electrolytes against both highvoltage cathodes and Li with the formation of robust interphase films on the surfaces.Herein,we report a highly fluorinated ether,1,1,1-trifluoro-2-[(2,2,2-trifluoroethoxy)methoxy]ethane(TTME),as a cosolvent,which not only functions as a diluent forming a localized high concentration electrolyte(LHCE),but also participates in the construction of the inner solvation structure.The TTME-based electrolyte is stable itself at high voltage and induces the formation of a unique double-layer solid electrolyte interphase(SEI)film,which is embodied as one layer rich in crystalline structural components for enhanced mechanical strength and another amorphous layer with a higher concentration of organic components for enhanced flexibility.The Li||Cu cells display a noticeably high Coulombic efficiency of 99.28%after 300 cycles and Li symmetric cells maintain stable cycling more than 3200 h at 0.5 mA/cm^(2) and 1.0m Ah/cm^(2).In addition,lithium metal cells using LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) and Li CoO_(2) cathodes(both loadings~3.0 m Ah/cm^(2))realize capacity retentions of>85%over 240 cycles with a charge cut-off voltage of 4.4 V and 90%for 170 cycles with a charge cut-off voltage of 4.5 V,respectively.This study offers a bifunctional ether-based electrolyte solvent beneficial for high-voltage Li metal batteries.

关键词： Lithium metal batteries High-voltage layered oxides Fluorinated ether-based electrolytes Solid electrolyte interphase Cathode electrolyte interphase

CEMA-LSTM:Enhancing Contextual Feature Correlation for Radar Extrapolation Using Fine-Grained Echo Datasets

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Computer Modeling in Engineering & Sciences 2023年第4期135卷 45-64页

作者： Zhiyun Yang Qi Liu HaoWu Xiaodong Liu yonghong zhang School of Computer and Software Engineering Research Center of Digital ForensicsMinistry of EducationNanjing University of Information Science and TechnologyNanjing210044China School of Computing Edinburgh Napier UniversityEdinburghEH105DTUK School of Automation Nanjing University of Information Science TechnologyNanjing210044China

Accurate precipitation nowcasting can provide great convenience to the public so they can conduct corresponding arrangements in advance to deal with the possible impact of upcoming heavy rain.Recent relevant research activities have shown their concerns on various deep learning models for radar echo extrapolation,where radar echo maps were used to predict their consequent moment,so as to recognize potential severe convective weather events.However,these approaches suffer from an inaccurate prediction of echo dynamics and unreliable depiction of echo aggregation or dissipation,due to the size limitation of convolution filter,lack of global feature,and less attention to features from previous states.To address the problems,this paper proposes a CEMA-LSTM recurrent unit,which is embedded with a Contextual Feature Correlation Enhancement Block(CEB)and a Multi-Attention Mechanism Block(MAB).The CEB enhances contextual feature correlation and supports its model to memorize significant features for near-future prediction;the MAB uses a position and channel attention mechanism to capture global features of radar echoes.Two practical radar echo datasets were used involving the FREM and CIKM 2017 datasets.Both quantification and visualization of comparative experimental results have demonstrated outperformance of the proposed CEMA-LSTMover recentmodels,e.g.,PhyDNet,MIM and PredRNN++,etc.In particular,compared with the second-rankedmodel,its average POD,FAR and CSI have been improved by 3.87%,1.65%and 1.79%,respectively on the FREM,and by 1.42%,5.60%and 3.16%,respectively on the CIKM 2017.

关键词： Radar echo extrapolation attention mechanism long short-term memory deep learning

Autophagy,not apoptosis,plays a role in lumen formation of eccrine gland organoids

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Chinese Medical Journal 2022年第3期135卷 324-332页

作者： Lijie Du Lei zhang Junhong Zhao Zixiu Chen Xiang Liu Manxiu Cao Lei You yonghong zhang Xiaobing Fu Haihong Li Department of Wound Repair and Dermatologic Surgery Taihe HospitalHubei University of MedicineShiyanHubei 442000China Hubei Clinical Medical Research Center of Cord Blood Hematopoietic Stem Cells Taihe HospitalHubei University of MedicineShiyanHubei 442000China Mental Health Center Taihe HospitalHubei University of MedicineShiyanHubei 442000China School of Basic Medicine Academy of Bio-Medicine ResearchHubei University of MedicineShiyanHubei Wound Healing and Cell Biology Laboratory The First Affiliated HospitalChinese PLA General HospitalBeijing 100048China

Background:Sweat secreted by eccrine sweat glands is transported to the skin surface through the lumen.The eccrine sweat gland develops from the initial solid bud to the final gland structure with a lumen,but how the lumen is formed and the mechanism of lumen formation have not yet been fully elucidated.This study aimed to investigate the mechanism of lumen formation of eccrine gland organoids(EGOs).Methods:Human eccrine sweat glands were isolated from the skin for tissue culture,and the primary cultured cells were collected and cultured in Matrigel for 14 daysin vitro.EGOs at different development days were collected for hematoxylin and eosin(H&E)staining to observe morphological changes and for immunofluorescence staining of proliferation marker Ki67,cellular motility marker filamentous actin(F-actin),and autophagy marker LC3B.Western blotting was used to detect the expression of Ki67,F-actin,and LC3B.Moreover,apoptosis was detected using a terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)apoptosis assay kit,and the expression of poly(ADP-ribose)polymerase and Caspase-3 was detected by Western blot.In addition,3-methyladenine(3MA)was used as an autophagy inhibitor to detect whether the formation of sweat glands can be effectively inhibited.Results:The results showed that a single gland cell proliferated rapidly and formed EGOs on day 4.The earliest lumen formation was observed on day 6.From day 8 to day 14,the rate of lumen formation in EGOs increased significantly.The immunofluorescence and Western blot analyses showed that the expression of Ki67 gradually decreased with the increase in days,while the F-actin expression level did not change.Notably,the expression of autophagy marker LC3B was detected in the interior cells of EGOs as the apoptosis signal of EGOs was negative.Compared with the control group,the autophagy inhibitor 3MA can effectively limit the formation rate of the lumen and reduce the inner diameter of EGOs.Conclusion:Using our model of eccrine gland 3D-reconstruction in Matri

关键词： Eccrine sweat glands Autophagy Apoptosis Lumen formation Organoids