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One-Pot Stereoselective Synthesis of Different Fused Multicyclic Iminosugars Based on the Iminium-lon Intermediate

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Chinese Journal of Chemistry 2024年第2期42卷 142-150页

作者： song Xie Jilai Wu Likai Zhou Chao Wei Xiaoliu Li hua Chen Key Laboratoryof Chemical Biology of Hebei Province College of Chemistry and Material ScienceHebei UniversityBaodingHebei 071002China College of Chemistry and Chemical Engineering Xingtai UniversityXingtaiHebei 054001China

Different novel fused multicyclic iminosugars were synthesized from D-ribose tosylate,aniline and vinyl ethyl ether by one-pot three-component stereoselective[4+2]reaction at different temperatures.The iminium-ion is the key intermediate for the reaction.As a result,several complex fused iminosugars 3a were obtained by aza-Diels-Alder mechanism at 60℃,while a series of aza-C-glycosides 5a were prepared by Mannich reaction at room temperature accompanied by another tetrahydroquinoline-fused iminosugars 4a(tricyclic derivatives)through aza-Diels-Alder cycloaddition.This strategy will help to construct structurally diverse and bioactive iminosugar analogues.

关键词： Fused multicyclic iminosugar Aza-Diels-Alder cycloaddition Mannich reaction Tetrahydroquinoline Multicomponent reactions Enantioselectivity Cyclization

Buried interface management via bifunctional NH_(4)BF_(4)towards efficient CsPbI_(2)Br solar cells with a V_(oc)over 1.4 V

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Journal of Energy Chemistry 2024年第2期89卷 364-370,I0009页

作者： Fazheng Qiu Ming-hua Li Jinpeng Wu Jin-song Hu School of Materials Science and Engineering NingboTech UniversityNingbo 315100ZhejiangChina Beijing National Laboratory for Molecular Sciences(BNLMS) Institute of ChemistryChinese Academy of SciencesBeijing 100190China College of Chemical Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

CsPbI_(2)Br perovskite solar cells(PSCs)have drawn tremendous attention due to their suitable bandgap,excellent photothermal stability,and great potential as an ideal candidate for top cells in tandem solar cells.However,the abundant defects at the buried interface and perovskite layer induce severe charge recombination,resulting in the open-circuit voltage(V_(oc))output and stability much lower than anticipated.Herein,a novel buried interface management strategy is developed to regulate interfacial carrier dynamics and CsPbI_(2)Br defects by introducing ammonium tetrafluoroborate(NH_(4)BF_(4)),thereby resulting in both high CsPbI_(2)Br crystallization and minimized interfacial energy losses.Specifically,NH_(4)^(+)ions could preferentially heal hydroxyl groups on the SnO_(2)surface and balance energy level alignment between SnO_(2)and CsPbI_(2)Br,enhancing charge transport efficiency,while BF_(4)^(-)anions as a quasi-halogen regulate crystal growth of CsPbI_(2)Br,thus reducing perovskite defects.Additionally,it is proved that eliminating hydroxyl groups at the buried interface enhances the iodide migration activation energy of CsPbI_(2)Br for strengthening the phase stability.As a result,the optimized CsPbI_(2)Br PSCs realize a remarkable efficiency of 17.09%and an ultrahigh V_(oc)output of 1.43 V,which is one of the highest values for CsPbI_(2)Br PSCs.

关键词： Inorganic perovskite Buried interface Defect Stability Open-circuit voltage loss

On the Quantum Cohomology of Blow-ups of Four-dimensional Quadrics

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Acta Mathematica Sinica,English Series 2024年第1期40卷 313-328页

作者： Jian Xun HU hua Zhong KE Chang Zheng LI Lei song School of Mathematics Sun Yat-sen UniversityGuangzhou 510275P.R.China

We propose a conjecture relevant to Galkin’s lower bound conjecture,and verify it for the blow-ups of a four-dimensional quadric at a point or along a projective plane.We also show that Conjecture O holds in these tw... 详细信息

关键词： Quantum cohomology blow-up quadric hypersurface

Bioinspired Tactile Sensation Based on Synergistic Microcrack-Bristle Structure Design toward High Mechanical Sensitivity and Direction-Resolving Capability

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Research 2024年第1期2023卷 611-624页

作者： Yiqun Zhang Qi Liu Wenjuan Ren Yangyang song hua Luo Yangyang Han Liang He Xiaodong Wu Zhuqing Wang School of Mechanical Engineering Sichuan UniversityChengdu 610065China Med+X Center for Manufacturing West China HospitalSichuan UniversityChengdu 610041China State Key Laboratory of Polymer Materials Engineering Polymer Research Institute of Sichuan UniversityChengdu 610065China

Natural tactile sensation is complex,which involves not only contact force intensity detection but also the perception of the force direction,the surface texture,and other mechanical parameters.Nevertheless,the vast majority of the developed tactile sensors can only detect the normal force,but usually cannot resolve shear force or even distinguish the directions of the force.Here,we present a new paradigm of bioinspired tactile sensors for resolving both the intensity and the directions of mechanical stimulations via synergistic microcrack-bristle structure design and cross-shaped configuration engineering.The microcrack sensing structure gives high mechanical sensitivity to the tactile sensors,and the synergistic bristle structure further amplifies the sensitivity of the sensors.The cross-shaped configuration engineering of the synergistic microcrack-bristle structure further endows the tactile sensors with good capability to detect and distinguish the directions of the applied mechanical forces.The as-fabricated tactile sensors exhibit a high sensitivity(25.76 N^(−1)),low detection limit(5.4 mN),desirable stability(over 2,500 cycles),and good capability to resolve both mechanical intensity and directional features.As promising application scenarios,surface texture recognition and biomimetic path explorations are successfully demonstrated with these tactile sensors.This newly proposed tactile sensation strategy and technology have great potential applications in ingenious tactile sensation and construction of various robotic and bionic prostheses with high operational dexterity.

关键词： crack sensation directions

Loss of heterozygosity for chromosomes 16q in Wilms tumors predicts outcomes:A meta-analysis

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 2159-2167页

作者： Yuan-hua song Wen-Ling Li Zhen Yang Yan Gao Zhi-Ping Feng Department of Oncology Kunming Children's HospitalKunming 650103Yunnan ProvinceChina Department of Nuclear Medicine The Third Affiliated Hospital of Kunming Medical University(Yunnan Cancer Hospital)Kunming 650118Yunnan ProvinceChina

BACKGROUND The research findings suggest that the prognosis of children with Wilms tumor(WT)is affected by various factors.Some scholars have indicated that loss of heterozygosity(LOH)on chromosome 16q is associated with a poor prognosis in patients with WT.AIM To further elucidate this relationship,we conducted a meta-analysis.METHODS This meta-analysis was registered in INPLASY(INPLASY2023100060).We systematically searched databases including Embase,PubMed,Web of Science,Cochrane,and Google Scholar up to May 31,2020,for randomized trials reporting any intrapartum fetal surveillance approach.The meta-analysis was performed within a frequentist framework,and the quality and network inconsistency of trials were assessed.Odds ratios and 95%CIs were calculated to report the relationship between event-free survival and 16q LOH in patients with WT.RESULTS Eleven cohort studies were included in this meta-analysis to estimate the relationship between event-free survival and 16q LOH in patients with WT(I^(2)=25%,P<0.001).As expected,16q LOH can serve as an effective predictor of eventfree survival in patients with WT(risk ratio=1.95,95%CI:1.52–2.49,P<0.001).CONCLUSION In pediatric patients with WT,there exists a partial correlation between 16q LOH and an unfavorable treatment prognosis.Clinical detection of 16q chromosome LOH warrants increased attention to the patient’s prognosis.

关键词： Loss of heterozygosity Wilms tumor Survival time Chromosomes 16q

Comprehensive analysis of the potential pathogenesis of COVID-19 infection and liver cancer

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 436-457页

作者： Yao Rong Ming-Zheng Tang song-hua Liu Xiao-Feng Li Hui Cai First Clinical Medical College Gansu University of Chinese MedicineLanzhou 730000Gansu ProvinceChina General Surgery Clinical Medical Center Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina Key Laboratory of Molecular Diagnostics and Precision Medicine for Surgical Oncology in Gansu Province Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina NHC Key Laboratory of Diagnosis and Therapy of Gastrointestinal Tumor Gansu Provincial HospitalLanzhou 730000Gansu ProvinceChina

BACKGROUND A growing number of clinical examples suggest that coronavirus disease 2019(COVID-19)appears to have an impact on the treatment of patients with liver cancer compared to the normal population,and the prevalence of COVID-19 is significantly higher in patients with liver cancer.However,this mechanism of action has not been clarified.Gene sets for COVID-19(GSE180226)and liver cancer(GSE87630)were obtained from the Gene Expression Omnibus database.After identifying the common differentially expressed genes(DEGs)of COVID-19 and liver cancer,functional enrichment analysis,protein-protein interaction network construction and scree-ning and analysis of hub genes were performed.Subsequently,the validation of the differential expression of hub genes in the disease was performed and the regulatory network of transcription factors and hub genes was constructed.RESULTS Of 518 common DEGs were obtained by screening for functional analysis.Fifteen hub genes including aurora kinase B,cyclin B2,cell division cycle 20,cell division cycle associated 8,nucleolar and spindle associated protein 1,etc.,were further identified from DEGs using the“cytoHubba”plugin.Functional enrichment analysis of hub genes showed that these hub genes are associated with P53 signalling pathway regulation,cell cycle and other functions,and they may serve as potential molecular markers for COVID-19 and liver cancer.Finally,we selected 10 of the hub genes for in vitro expression validation in liver cancer cells.CONCLUSION Our study reveals a common pathogenesis of liver cancer and COVID-19.These common pathways and key genes may provide new ideas for further mechanistic studies.

关键词： COVID-19 Liver cancer Differentially expressed genes Hub genes Pathogenesis

Effect of cerium on microstructure,texture and properties of ultrahigh-purity copper

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Journal of Rare Earths 2024年第1期42卷 220-227,I0008页

作者： Yunxiao hua Haitao Liu Kexing song Jiangwei Wang Yin'gang Guo Jing Tian Huiwen Guo Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology School of Materials Science and EngineeringHenan University of Science and TechnologyLuoyang471023China Henan Academy of Sciences Zhengzhou450000China Center of Electron Microscopy and State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Henan Zhongyuan Gold Smelter Co. Ltd.Sanmenxia472100China Chinalco Luoyang Copper Processing Co. Ltd.Luoyang471039China

The effects of Ce addition(310 ppm and 1500 ppm)on the microstructure,texture and properties of ultrahigh-purity copper(99.99999%)were systematically studied using scanning electron microscopy(SEM),transmission electron microscopy(TEM)and electron backscattered diffraction(EBSD)analyses,combined with the microhardness and conductivity tests.Regarding the microstructure of the as-cast and as-extruded samples,the addition of Ce refines the grain size of the ultrahigh-purity copper and the refinement effect of 310Ce alloy is greater than that of 1500Ce alloy.This is due to the stronger compone nt supercooling and the accele rated recrystallization caused by lower Ce co ntent.In addition,Ce can react with Cu to form the Cu-Ce eutectic phases,which are deformable during the hot deformation.Furthermore,the added Ce can weaken the texture,showing a variation of brass recrystallization(BR),rotated cube,copper and S texture components,which depends on the recrystallization,the particle stimulated nucleation(PSN)as well as the stacking fault energy(SFE).Most remarkably,the introduction of Ce enhances the hardness of the ultrahigh-purity copper without obviously reducing its conductivity.The major{111}orientations and the stress distributions are responsible for such a superior conductivity of the Ce-containing alloys.

关键词： Ce addition Grain refinement Texture Conductivity Ultrahigh-purity copper Rare earths

C_(Ar)-Br bond cleavage via cooperative EnT/NHC catalysis: mild access to indolines

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Science China Chemistry 2024年第3期67卷 922-927页

作者： Yi-Xiong Dong Cao-Bo Li Ming-Lei Jin Zhong-hua Gao song Ye Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The cooperative visible-light mediated and NHC-catalyzed dearomative arylation-acylation of N-(2-bromobenzoyl)indoles with aldehydes was developed, affording the corresponding highly functionalized polycyclic indolines in moderate to good yields with exclusive diastereoselectivities. Mechanism investigations support the activation of CAr-Br bond via visible-light mediated energy transfer(EnT) and the following single-electron-transfer(SET) with Breslow intermediate under NHC catalysis to give key aryl radical and ketyl radical. This protocol demonstrates the cleavage of CAr-Br bond under mild cooperative EnT/NHC catalysis.

关键词： energy transfer N-heterocyclic carbenes photocatalysis aryl radicals indolines

Recent progress of Pt-based oxygen reduction reaction catalysts for proton exchange membrane fuel cells

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Rare Metals 2024年第6期43卷 2444-2468页

作者： Feng Zhan Kun-song Hu Jin-hua Mai Li-Sheng Zhang Zhen-Guo Zhang huan He Xin-hua Liu School of Resources Environment and MaterialsGuangxi University School of Transportation Science and Engineering Beihang University IDTECH (Suzhou) Co.Ltd Dyson School of Design Engineering Imperial College London

With the increasing consumption of fossil fuels,proton exchange membrane fuel cells(PEMFCs) have attracted considerable attention as green and sustainable energy conversion devices.The slow kinetics of the cathodic oxygen reduction reaction(ORR) has a major impact on the performance of PEMFCs,and although platinum(Pt) can accelerate the reaction rate of the ORR,the scarcity and high cost of Pt resources still limit the development of PEMFCs.Therefore,the development of low-cost high-performance ORR catalysts is essential for the commercial application and development of PEMFCs.This paper reviews the research progress of researchers on Pt-based ORR catalysts in recent years,including Pt/C catalysts,Pt-based alloy catalysts,Pt-based intermetallic compounds,and Pt-based single-atom catalysts(SACs),with a focus on Pt-based alloy catalysts with different nanostructures.We described in detail the difficulties and solutions in the research process of various ORR catalysts and explained the principle of their activity enhancement with density functional theory(DFT).In addition,an outlook on the development of Pt-based catalysts is given,and reducing the amount of Pt used and improving the performance of catalysts are the directions to work on in the coming period.

关键词： Pt-based catalysts PEMFCs Pt-based intermetallic compounds Single-atom catalysts