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One-pot synthesis of a giant twisted double-layer chiral macrocycle via [4+8] imine condensation and its X-ray structure

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Chinese chemical Letters 2024年第10期35卷 267-269页

作者： yu Pang min Wang Ning-{2. Yang min Xue Yong Yang School of Science Department of Physics Key Laboratory of Optical Field Manipulation of Zhejiang Province Zhejiang Sci-Tech University School of Chemistry and chemical engineering Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province Zhejiang Sci-Tech University

Trifluoroacetic acid （TFA） catalyzed condensation reaction between tetraaminooxacalix[4]arene and N-alkylcarbazole-3,6-dicarbaldehyde in CH2.l2.fforded a single product in 87%–89%***-defined yet undissolvable1H NMR spectra suggested formation of robust and discrete structures in solution.X-ray single crystal analysis further revealed a giant twisted double-layer chiral macrocycle in the solid state,which was formed from[4+8]condensation of the two reactants via 16 imine *** calculations discovered that only the[4+8]twisted product is thermodynamically favorable,which accounts for its highly selective and efficient formation out of a library of many other combinations.

关键词： Chiral macrocycle Dynamic covalent chemistry One-pot synthesis Oxacalixarene X-ray single crystal

Catalytic asymmetric dearomative azo-Diels–Alder reaction of 2.vinlyindoles

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Chinese chemical Letters 2024年第4期35卷 357-362页

作者： yu-Hang Miao zheng-Xu Zhang Xu-Yi {2.ng yuan-Zhao {2. Shi-Kun Jia Xiao Xiao min-Can Wang Li-Ping Xu Guang-Jian Mei Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450052China School of Chemistry and chemical engineering Shandong University of TechnologyZibo 255000China Institute of Pharmaceutical Science and technology Zhejiang University of TechnologyHangzhou 310014China

due to the high electrophilic nature of azo-dienophiles, azo-Diels–Alder proceeds rapidly even without the need of a catalyst and is therefore regarded as the “click reaction”. This spontaneity causes strong background reaction and poses a daunting challenge to chemists for developing the catalytic asymmetric version. Reported herein is the first catalytic asymmetric dearomative azo-Diels–Alder reaction between2.vinylindoles and triazoledione. This protocol makes use of the high energy barrier of dearomatization to avert the strong background reaction of azo-Diels–Alder reaction, allowing the implementation of the projected reaction at ambient temperature. Density functional theory calculations have been performed to gain insights into the reaction mechanism and the origins of the enantioselectivity. By using this method,a variety of tetracyclic indole derivatives have been readily prepared in good to excellent yields and with excellent diastereo-and enantio–selectivities(33 examples, up to 97% yield and >99% ee, >2.:1 dr).

关键词： Catalytic asymmetric dearomatization Azo-Diels–Alder reaction 2.Vinylindoles Chiral phosphoric acid Tetracyclic indole derivatives

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Trends and hotspots in gastrointestinal neoplasms risk assessment: A bibliometric analysis from 1984 to 2.2.

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2842-2861页

作者： Qiang-Qiang Fu Le Ma Xiao-min Niu hua-Xin Zhao Xu-hua Ge hua Jin De-hua yu Sen Yang department of General Practice Yangpu HospitalSchool of MedicineTongji UniversityShanghai 200090China Shanghai General Practice and Community Health Development Research Center Shanghai 200090China department of Shanghai Lung Cancer Center Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030China department of Oncology Shanghai Tenth People’s HospitalTongji University School of MedicineShanghai 200090China

BACKGROUND Gastrointestinal neoplasm(GN)significantly impact the global cancer burden and mortality,necessitating early detection and *** the evolution and current state of research in this field is *** To conducts a comprehensive bibliometric analysis of publications from 1984 to 2.2. to elucidate the trends and hotspots in the GN risk assessment research,focusing on key contributors,institutions,and thematic *** This study conducted a bibliometric analysis of data from the Web of Science Core Collection database using the"bibliometrix"R package,VOSviewer,and *** analysis focused on the distribution of publications,contributions by institutions and countries,and trends in *** methods included data synthesis,network analysis,and visualization of international collaboration *** This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and *** highlights the United States'critical role in advancing this field,with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer *** last five years,substantial advancements have been made,representing nearly 45%of the exa{2.ed *** rates have dramatically increased,from 2. articles in 2.02.to 112.in 2.2.,reflecting intensified research *** study underscores a growing trend toward interdisciplinary and international collaboration,with the Journal of Clinical Oncology standing out as a key publication *** shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN *** This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research *** calls for enhanced global collaboration and integration of artificial intelligence to improve cancer p

关键词： Gastrointestinal neoplasms Bibliometric analysis Risk assessment Network analysis Research trends

Predicting hepatocellular carcinoma: A new non-invasive model based on shear wave elastography

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World Journal of Gastroenterology 2024年第25期30卷 3166-3178页

作者： Dong Jiang Yi Qian Yi-Jun Gu Ru Wang hua yu Hui Dong Dong-yu Chen Yan Chen Hao-zheng Jiang Bi-Bo Tan min Peng Yi-Ran Li department of Ultrasound Eastern Hepatobiliary Surgery HospitalThe Third Affiliated Hospital of Naval Medical UniversityShanghai 200433China department of Pathology Shanghai Eastern Hepatobiliary Surgery HospitalThird Affiliated Hospital of Naval Medical UniversityShanghai 200433China department of College of Art and Science Case Western Reserve UniversityClevelandOH 44106United States Ultrasound Diagnosis PLA Naval Medical CenterShanghai 200437China

BACKGROUND Integrating conventional ultrasound features with 2. shear wave elastography(2.-SWE)can potentially enhance preoperative hepatocellular carcinoma(HCC)*** To develop a 2.-SWE-based predictive model for preoperative identification of *** A retrospective analysis of 884 patients who underwent liver resection and pathology evaluation from February 2.2. to August 2.2. was conducted at the Oriental Hepatobiliary Surgery *** patients were divided into the modeling group(n=72.)and the control group(n=164).The study included conventional ultrasound,2.-SWE,and preoperative laboratory *** logistic regression was used to identify independent predictive factors for RESULTS In the modeling group analysis,maximal elasticity(Emax)of tumors and their peripheries,platelet count,cirrhosis,and blood flow were independent risk indicators for *** factors yielded an area under the curve of 0.77(95%confidence interval:0.73-0.81)with 84%sensitivity and 61%*** model demonstrated good calibration in both the construction and validation cohorts,as shown by the calibration graph and Hosmer-Lemeshow test(P=0.683 and P=0.658,respectively).Additionally,the mean elasticity(Emean)of the tumor periphery was identified as a risk factor for microvascular invasion(MVI)in malignant liver tumors(P=0.003).Patients receiving antiviral treatment differed significantly in platelet count(P=0.002.,Emax of tumors(P=0.033),Emean of tumors(P=0.042.,Emax at tumor periphery(P1),and Emean at tumor periphery(P=0.003).CONCLUSION 2.-SWE’s hardness value serves as a valuable marker for enhancing the preoperative diagnosis of malignant liver lesions,correlating significantly with MVI and antiviral treatment efficacy.

关键词： Shear wave elastography Predicting model Microvascular invasion Antiviral treatment Hepatocellular carcinoma

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting

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Frontiers in Energy 2024年第3期18卷 378-389页

作者： Zhao-ting SHANG Tang-ming LI Bing-qian HU min LIU Wang-ting LU Fan {2. {2.n zheng Key Laboratory of Optoelectronic chemical Materials and Devices of ministry of E{2.cation College of Optoelectronic Materials and TechnologyJianghan UniversityWuhan 430056China Institute of New Energy Materials and engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China department of chemical{2. University of WaterlooWaterlooOntario N2L 3G1Canada

The use of two-dimensional(2.)layered metal-organic frameworks(MOFs)as self-sacrificial templates has been proven to be a successful method to create high-efficiency Selenium(Se)-containing electrocatalysts for overall water ***,two strategies are then utilized to introduce Se element into the Co–Fe MOF,one being the etching of as-prepared MOF by SeO_(2. solution,and the other,the replacing of SCN−with SeCN−as the construction *** electrochemical activity of the pristine 2. MOF and their calcinated derivatives for catalyzing the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is evaluated and further *** is found that the effect of introducing Se on improving electrochemical catalytic activity is significant for the HER ***,the calcinated derivative in the replacing method exhibits an overpotential of 2.5 mV for HER and 2.0 mV for OER at a current density of 10 mA/*** comparing the two methods of introducing Se element into MOF,similar electrocatalytic activity can be achieved on the their calcinated *** high electrochemical performance of 2. CoFe-MOF derivatives may be resulted from the unique 2. hierarchical porous structure and strong synergistic effect between different components in the material.

关键词： 2. MOF selenium(Se)-containing materials hydrogen evolution reaction(HER) oxygen evolution reaction(OER)

Dapagliflozin in heart failure and type 2.diabetes:Efficacy,cardiac and renal effects,safety

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World Journal of Diabetes 2024年第7期15卷 1518-1530页

作者： Pei-Ling yu You yu S{2.ng Li Bai-Chen Mu ming-{2. Nan min Pang The Second department of Cardiology The Second Affiliated Hospital of Liaoning Hospital of Traditional Chinese MedicineShenyang 110034Liaoning ProvinceChina department of Outpatient The Second Affiliated Hospital of Liaoning University of Traditional Chinese MedicineShenyang 110034Liaoning ProvinceChina

BACKGROUND Heart failure(HF),especially HF with reduced ejection fraction(HFrEF),presents complex challenges,particularly in the aging population where it often coexists with type 2.diabetes mellitus(T2.M).AIM To analyze the effect of dapagliflozin treatment on cardiac,renal function,and safety in patients with HFrEF combined with *** Patients with T2.M complicated with HFrEF who underwent treatment in our hospital from February 2.1. to March 2.2. were retrospectively analyzed as the subjects of this *** propensity score matching method was used,and a total of 102.eligible samples were *** clinical efficacy of the two groups was evaluated at the end of the treatment,comparing the results of blood glucose,insulin,cardiac function,markers of myocardial injury,renal function indexes,and 6-{2. walk test(6MWT)before and after the *** compared the occurrence of adverse effects on the treatment process of the two groups of *** incidence of adverse outcomes in patients within six months of treatment was *** The overall clinical efficacy rate of patients in the study group was significantly higher than that of patients in the control group(P=0.013).After treatment,the pancreatic beta-cell function index,left ventricular ejection fraction,and glomerular filtration rate of patients in the study group were significantly higher than control group(P2.h postprandial glucose,glycosylated hemoglobin,insulin resistance index,left ventricular end-systolic diameter,left ventricular end-diastolic diameter,cardiac troponin I,creatine kinase-MB,N-ter{2.al pro b-type natriuretic peptide,serum creatinine,and blood urea nitrogen were significantly lower than those of the control *** treatment,patients in the study group had a significantly higher 6MWT than those in the control group(P<0.001).Hypoglycemic reaction(P=0.647),urinary tract infection(P=0.558),gastrointestinal adverse effect(P=0.

关键词： Heart failure Type 2.diabetes mellitus Heart failure with preserved ejection fraction Myocardial infarction markers Cardiac function

Resistance of Si_2._2. ceramics to oxidation and erosion of molten silica

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中国有色金属学会会刊：英文版 2000年第3期10卷 418-420页

作者： WANG Si qing(王思青) 1, YAN yu hua(阎玉华) {2. department of Materials engineering and Applied Chemistry, National {2. of Defense technology, Changsha 410073, P.R.china 2. Biomaterials engineering Center, wuhan university of technology, W 国防科技大学湖南长沙武汉工业大学湖北武汉

Si 2. 2. ceramics was fabricated from powder by hot pressing in N 2.atmosphere. The resistance of the ceramic sample to oxidation and erosion of molten silica was investigated. The bulk density and open porosity of the ceramic sample were measured according to the Archimedes principle in water. Then fracture surface of the sintered body was observed by SEM. The results and analysis indicate that the resistance of Si 2. 2. ceramics to oxidation and erosion of molten silica increases when its density increases and/or its open porosity decreases. Moreover, they also reveal that the oxidation process is an unsteady dispersing process with oxygen as the constant source, and the resistance to erosion of molten silica related to the quantity of grain boundary in unit surface area. The lowest mass gain is 2.4 g/m 2.after oxidizing at 1 000 ℃ for 100 h in air, while the lowest mass loss is 2.9 g/m 2.after 40 h erosion in molten silica.

关键词： silicon oxynitride ceramics chemical stability

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Donor-acceptor covalent organic frameworks-confined ultrafine bimetallic Pt-based nanoclusters for enhanced photocatalytic H_(2.generation

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Nano Research 2024年第7期17卷 5835-5844页

作者： yu Liu Yawen Shi hua Wang Shengbo Zhang Collaborative Innovation Center of chemical Science and engineering(Tianjin) Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China School of Environmental Science and engineering Tianjin Key Laboratory of Biomass/Wastes UtilizationTianjin UniversityTianjin 300350China

Photocatalytic hydrogen generation from hydrogen storage media is an effective and promising approach for the green hydrogen industry as well as for achieving carbon neutrality ***,the lower photocatalytic efficiency due to the limited light trapping capacity,low electron transfer rate,and severe aggregation of nanoparticles caused by high surface energy seriously restricts their practical ***,we constructed a series of donor–acceptor(D–A)type covalent organic frameworks to confine ultrafine bimetallic Pt-based nanoclusters for photocatalytic hydrogen generation from ammonia borane(AB)*** visible light irradiation at 2.℃,PtCo_(2.@covalent organic framework(COF)showed the highest photocatalytic activity with a turnover frequency(TOF)of 486 {2.−*** and density functional theory(DFT)calculations reveal that the high catalytic activity is mainly attributed to the strong electronic interactions between D–A type COF and ultrafine PtCo_(2.***,the D–A type COF can significantly enhance the light-trapping ability by fine-tuning the electron-acceptor type in the framework,and accelerate the photogenerated electron transfer from D–A type COF to PtCo_(2.nanocluster,which promotes the adsorption and activation of H_(2.O and AB molecules and accelerates hydrogen ***,PtCo_(2.@COF also exhibited ultra-high durability due to the significantly enhanced resistance to nanocluster aggregation caused by the nanopore confinement effect of D–A type *** believe that this work will provide a theoretical guide for the rational design of efficient D–A COFbased catalysts for photocatalysis.

关键词： light trapping electron transfer donor-acceptor covalent organic frameworks(D-A COFs) bimetallic nanoclusters photocatalysis

Synergetic PVA degradation and H2.evolution in photocatalytic fuel cells using Ag@Fe_(2.O_(3) cathode

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Frontiers of chemical Science and engineering 2024年第1期18卷 85-93页

作者： Likun Sun Kesi Xiong Baoning Zhang Jinghong Fang Yingchao He min Wang Zhixing Gan Fanglin du Qiong Sun Liyan {2. Lifeng Dong College of Materials Science and engineering Qingdao University of Science and TechnologyQingdao 266042China Center for Future Optoelectronic Functional Materials School of Computer and Electronic InformationNanjing Normal UniversityNanjing 210023China department of Physics Hamline UniversitySt.Paul 55104USA

In a dual-chamber photocatalytic fuel cell device,polyvinyl alcohol degradation and H2.evolution were concurrently *** setup involved commercial P2. as the photoanode and Ag@Fe_(2.O_(3) nanoparticles as the ***,the feasibility of a Fentonlike reaction in the cathode,utilizing Fe^(2.)ions and pumped O_(2.,was *** cathode materials,polyvinyl alcohol types,and pH values’effects were assessed on device *** tests highlighted photoinduced holes(h+)and OH·radicals as pivotal contributions to polyvinyl alcohol ***-term stability of the device was established through cycling experiments.

关键词： photocatalytic fuel cell PVA Ag@Fe_(2.O_(3) cathode materials Fenton-like reaction