检索结果-南通市图书馆

Quantum geometric tensor and the topological characterization of the extended Su-Schrieffer-Heeger model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese Physics B 2024年第3期33卷 260-265页

作者：曾相龙赖文喜魏祎雯马余全 School of Science Beijing Information Science and Technology UniversityBeijing 100192China

We investigate the quantum metric.and topological Euler number in a cyclically modulated Su-Schrieffer-Heeger(SSH)model with long-range hopping *** computing the quantum geometry tensor,we derive exact expressions for the quantum metric.and Berry curvature of the energy band electrons,and we obtain the phase diagram of the model marked by the first chern ***,we also obtain the topological Euler number of the energy band based on the Gauss-Bonnet theorem on the topological characterization of the closed Bloch states manifold in the first Brillouin ***,some regions where the Berry curvature is identically zero in the first Brillouin zone result in the degeneracy of the quantum metric,which leads to ill-defined non-integer topological Euler ***,the non-integer"Euler number"provides valuable insights and an upper bound for the absolute values of the chern numbers.

关键词： quantum geometric tensor topological Euler number chern number Berry curvature quantum metric Su-Schrieffer-Heeger(SSH)model

维普期刊数据库

Trial characteristics and treatment effect estimates in randomized controlled trials of chinese herbal medicine: A meta-epidemiological study

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Medicine 2024年第3期22卷 223-234页

作者： Betty H.Wang Ya-li Lin Yin-yan Gao Jin-lu Song Lang Qin Ling-qi Li wen-qi Liu claire c.W.Zhong Mary Y.Jiang chen Mao Xiao-bo Yang Vincent c.H.chung Irene X.Y.Wu Jockey club School of Public Health and Primary care the Chinese University of Hong KongHong Kong 999077China Xiangya School of Public Health Central South UniversityChangsha 410006Hunan ProvinceChina School of chinese Medicine the Chinese University of Hong KongHong Kong 999077China School of Public Health Southern Medical UniversityGuangzhou 510080Guangdong ProvinceChina State Key Laboratory of Dampness Syndrome of chinese Medicine the Second Affiliated Hospital of Guangzhou University of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina chinese Medicine Syndrome Research Team the Second Affiliated HospitalGuangzhou University of Chinese MedicineGuangzhou 510120Guangdong ProvinceChina Guangdong Provincial Key Laboratory of clinical Research on Traditional chinese Medicine Syndrome Guangzhou 510120Guangdong ProvinceChina Hunan Provincial Key Laboratory of clinical Epidemiology Central South UniversityChangsha 410006Hunan ProvinceChina

Background:Previously published meta-epidemiological studies focused on Western medicine have identified some trial characteristics that impact the treatment effect of randomized controlled trials(RcTs).Nevertheless,it remains unclear if similar associations exist in RcTs on chinese herbal medicine(cHM).Further,chinese medicine-related characteristics have not been explored ***:To investigate trial characteristics related to treatment effect estimates on cHM *** strategy:This meta-epidemiological study searched 5 databases for systematic reviews on cHM treatment published between January 2011 and July *** criteria:An eligible systematic review should only include RcTs of cHM and conduct at least one *** extraction and analysis:Two reviewers independently conducted data extraction on general characteristics of systematic reviews,meta-analyses and included *** also assessed the risk of bias of RcTs using the cochrane risk of bias tool.A two-step approach was used for data *** ratio of odds ratios(ROR) and difference in standardized mean differences (dSMD) with 95%confidence interval (cI) were applied to present the difference in effect estimates for binary and continuous outcomes,***:Ninety-one systematic reviews,comprising 1338 RcTs were *** binary outcomes,RcTs incorporated with syndrome differentiation (ROR:1.23;95%cI:[1.07,1.39]),adopting chinese medicine formula (ROR:1.19;95%cI:[1.03,1.34]),with low risk of bias on incomplete outcome data (ROR:1.29;95%cI:[1.06,1.52]) and selective outcome reporting (ROR:1.12;95%cI:[1.01,1.24]),as well as a trial size≥100 (ROR:1.23;95%cI:[1.04,1.42]) preferred to show larger effect *** for continuous outcomes,RcTs with chinese medicine diagnostic criteria (dSMD:0.23;95%cI:[0.06,0.41]),judged as high/unclear risk of bias on allocation concealment (dSMD:-0.70;95%cI:[-0.99,-0.42]),with low risk of bias on incomplete outcome data (dSMD:0.30

关键词： chinese herbal medicine Randomized controlled trial Risk of bias Meta-epidemiological study Effect estimates

维普期刊数据库

Single-source-precursor synthesis and air-plasma ablation behavior of(Ti,Zr,Hf)c/Sic ceramic nanocomposites at 2200℃

在线全文

学校读者我要写书评

暂无评论

Journal of Advanced ceramics 2024年第7期13卷 1043-1059页

作者： Li Lu Qingbo wen Jinrun Hu Tianxing Jiang Xiangchao Ren Yalei Wang Yi Zeng Xiang Xiong State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Dense monolithic(Ti,Zr,Hf)c/Sic ceramic nanocomposites with four different molar ratios of metallic elements in the(Ti,Zr,Hf)c phase(i.e.,Ti:Zr:Hf=1:1:1,2:3:5,2:3:3,and 1:2:1)were prepared upon pyrolysis of novel(Ti,Zr,Hf)-containing single-source precursors(SSPs),followed by spark plasma sintering(SPS).A thorough characterization was conducted to elucidate the synthesis of the SSPs,polymer-to-ceramic transformation,chemical/phase compositions,and microstructure of the SiTiZrHfc-based *** results revealed the feasibility of synthesizing nanocomposites with high(Ti,Zr,Hf)c contents using the SSP *** nanocomposites were characterized by a unique microstructure with in situ generated(Ti,Zr,Hf)c@c core-shell nanoparticles homogeneously mixed withβ-*** ablation behavior of the nanocomposites was evaluated on an air-plasma device for 60 ***,the nanocomposites exhibited excellent ablation resistance,and the lowest linear ablation rate reached−0.58μm/s at 2200°***,the ablation resistance can be dramatically improved by precisely tailoring the atomic ratios of metal elements within the(Ti,Zr,Hf)c phase via the molecular design of the *** formation of a multiple-oxide layer with both a high-meltingpoint phase((Ti,Zr,Hf)O_(2))and low-melting-point phases((Zr,Hf)TiO_(4))and glassy SiO_(2),as well as their structure,played a critical role in the enhanced ablation *** uniform distribution of the high-melting-point(Ti,Zr,Hf)O_(2)nano/microparticles throughout the glassy SiO_(2)matrix significantly enhanced the viscosity and stability of the oxide layer by the pinning effect,offering superior protection against the ingress of oxygen atoms and excellent resistance to mec.anical erosion.

关键词： ultrahigh-temperature ceramics(UHTcs) multicomponent carbide nanocomposites ablation behavior multiple oxides

Rhodium-catalyzed Regioselective c-O and c-c Bonds Formation of 3-Oxopent-4-enenitriles with Alkynes for the Synthesis of Polysubstituted 2H-Pyrans

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese Journal of chemistry 2024年第17期42卷 1986-1992页

作者： Kelu Yan Xiao Liu Jiangwei wen Qiuyun Li Junjie Wang Yang Zheng Xiu Wang Key Laboratory of Life-Organic.analysis of Shandong Province School of Chemistry and Chemical EngineeringQufu Normal UniversityQufuShandong273165China Faculty of chemistry and chemical Engineering Yancheng Institute of TechnologyYanchengJiangsu 224051China

The rhodium-catalyzed c-H bond activation and cyclization of 3-oxopent-4-enenitriles with alkynes proceed *** 2H-pyrans with multiple substituents are achieved in good yields through regioselective formation of c-O and c-c *** involving hydroxy-alkynoates resulted in products with a furo[3,4-b]pyran skeleton via further intramolecular ester exc.ange *** from the traditional"1-oxatrienes pathway",this method for the synthesis of useful 2H-pyrans possesses certain highlights in terms of readily available substrates,stable and easily derivatized products,gentle and convenient operation process,and step and atomeconomy.

关键词： Rhodium/c-H activation 3-Oxopent-4-enenitriles Alkynes 2H-Pyrans Transition metals Regioselectivity cyclization comprehensive Summary

M^(6)A modification in cardiovascular disease:With a focus on programmed cell death

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Genes & Diseases 2024年第5期11卷 272-284页

作者： wen Li Yao Liu Ruiyan Xu Yuan Zong Lu He Jun Hu Guohua Li Institute of cardiovascular Disease Key Laboratory for Arteriosclerology of Hunan ProvinceHunan International Scientific and Technological Cooperation Base of Arteriosclerotic DiseaseDepartment of PathophysiologyMOE Key Lab of Rare Pediatric DiseasesHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of cardiovascular Medicine The Second Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of Obstetrics and Gynecology The First Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China Department of cardiovascular Surgery The Second Affiliated HospitalHengyang Medical SchoolUniversity of South ChinaHengyangHunan 421001China

N^(6)-methyladenosine(m^(6)A)methylation is one of the most predominant internal RNA modifications in eukaryotes and has become a hot spot in the field of epigenetics in recent *** diseases(cVDs)are a leading cause of death *** evidence demonstrates that RNA modifications,such as the m^(6)A modification,are associated with the development and progression of many diseases,including *** increasing body of studies has indicated that programmed cell death(PcD)plays a vital role in ***,the molecular mec.anisms underlying m^(6)A modification and PcD in cVDs remain poorly ***,elaborating on the highly complex connections between the m^(6)A mec.anisms and different PcD signaling pathways and clarifying the exact molecular mec.anism of m^(6)A modification mediating PcD have significant meaning in developing new strategies for the prevention and therapy of *** is great potential for clinical application.

关键词： Apoptosis Autophagy cardiovascular diseases Ferroptosis N^(6)-methyladenosine Programmed cell death Pyroptosis

Transition-metal free trifluoromethylimination of alkenes enabled by direct activation of N-unprotected ketimines

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

chinese chemical Letters 2024年第9期35卷 155-159页

作者： Boqiang Wang Yongzhuo Xu Jiajia Wang Muyang Yang Guo-Jun Deng wen Shao Key Laboratory for Green Organic Synthesis and Application of Hunan Province Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of EducationCollege of ChemistryXiangtan UniversityXiangtan 411105China Department School of chemistry and chemical Engineering Henan Normal UniversityXinxiang 453007China

A highly site-selective intermolecular trifluoromethylimination of activated and unactivated olefins was reported under transition-metal-and photosensitizer-free *** newly developed strategy provides straightforward and efficient access to diverse value-added vicinal trifluoromethyl amines without resorting to the pre-functionalized *** experiments demonstrate that the approach proceeded through cF_(3)and iminyl two-radicals process,which were generated directly from commercially available benzophenone imine in a novel electron-donor mode via a SET process activated by the bifunctional hypervalent iodine *** synthetic potential of the protocols was further showcased via the condensation/amination sequential cascade,and transformations to accessβ-cF_(3)primary amines.

关键词： Transition-metal free Alkenes difunctionalization Amination Trifluoromethylation Single-electron transfer

维普期刊数据库

High performance 2T0c DRAM cells based on atomic-layer-deposited InAlZnO FETs

在线全文

学校读者我要写书评

暂无评论

Science china(Information Sciences) 2024年第9期67卷 344-345页

作者： wen XIONG Binbin LUO Wei MENG Bao ZHU Xiaohan WU Shi-Jin DING School of Microelectronics Fudan University

Recently, the oxide semiconductor-based 2T0c dynamic random-access memory(DRAM) has shown great potential in monolithic three-dimensional(M3D)-integrated memory,owing to some unique advantages of oxide semiconductors,such as high electron mobility, wide band gap, and compatibility with back-end-of-line(BEOL) processes [1, 2].

关键词：

correlation and Pathway Analysis of the carbon,Nitrogen,and Phosphorus in Soil-Microorganism-Plant with Main Quality components of Tea(camellia sinensis)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Phyton-International Journal of Experimental Botany 2024年第3期93卷 487-502页

作者： chun Mao Ji He Xuefeng wen Yangzhou Xiang Jihong Feng Yingge Shu college of Agriculture Guizhou UniversityGuiyangChina School of Geography and Resources Guizhou Education UniversityGuiyangChina

The contents of carbon(c),nitrogen(N),and phosphorus(P)in soil-microorganisms-plant signiﬁcantly affect tea quality by altering the main quality components of tea,such as tea polyphenols,amino acids,and ***,few studies have quantiﬁed the effects of these factors on the main quality components of *** study aimed to explore the interactions of c,N,and P in soil-microorganisms-plants and the effects of these factors on the main quality components of tea by using the path analysis *** results indicated that(1)The contents of c,N,and P in soil,microorganisms,and tea plants were highly correlated and collinear,and showed signiﬁcant correlations with the main quality components of tea.(2)Optimal regression equations were established to esti-mate tea polyphenol,amino acid,catechin,caffeine,and water extract content based on c,N,and P contents in soil,microorganisms,and tea plants(R^(2)=0.923,0.726,0.954,0.848,and 0.883,respectively).(3)Pathway analysis showed that microbial biomass phosphorus(MBP),root phosphorus,branch nitrogen,and microbial biomass carbon(MBc)were the largest direct impact factors on tea polyphenol,catechin,water extracts,amino acid,and caffeine content,*** carbon,root phosphorus,and leaf nitrogen were the largest indirect impact factors on tea polyphenol,catechin,and water extract content,*** carbon indirectly affected tea polyphenol content mainly by altering MBP *** phosphorus indirectly affected catechin content mainly by altering soil organic carbon *** nitrogen indirectly affected water extract content mainly by altering branch nitrogen *** research results provide the scientiﬁc basis for reasonable fertilization in tea gardens and tea quality improvement.

关键词： Soil-microorganisms-plant system carbon nitrogen phosphorus tea quality path analysis

Local resistance characteristics of elbows for supercritical pressure RP-3 flowing in serpentine micro-tubes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Propulsion and Power Research 2024年第2期13卷 245-256页

作者： Yanchen Fu Yinlong Liu Juan Wang Yu Wang Guoqiang Xu Jie wen Research Institute of Aero-engine Beihang UniversityBeijing 100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Beihang UniversityBeijing 100191China Zhongfa Aviation Institute of Beihang University Hangzhou 310023China AEcc Sichuan Gas Turbine Research Institute Chengdu 610500China AEcc Hunan Aviation Powerplant Research Institute Zhuzhou 412002China School of Energy and Power Engineering Beihang UniversityBeijing 100191China

Based on the demands of compact heat exc.angers and micro cooling c.annels applied for aviation thermal protection on aero-engines,the elbow localﬂow resistance charac-teristics for supercritical pressure aviation fuel RP-3ﬂowing in adiabatic horizontal serpentine tubes with the inner diameter of 1.8 mm and the massﬂux of 1179 kg/(m^(2)·s)were experimen-tally *** long-short-tube method was used to obtain the elbow pressure drop from the total serpentine tube pressure drop,and the effects of system pressures(P/Pc=1.72-2.58)and geometry parameters including bend numbers(n=5-11),bend diameters(D/d=16.7-27.8),and bend distances(L/d=20-60)on elbow pressure drops and local resistance co-efﬁcients are analyzed on the basis of the thermal physical property *** results show that both the increase in the elbow pressure drop and the decrease in the local resistance coef-ﬁcient with temperatures speed up at the near pseudo-critical temperature region of T>*** the growth of the elbow local pressure drop could be inhibited by the increase of system pressures,while the local resistance coefﬁcient is slightly affected by *** inﬂuence of bend diameters on the local resistance coefﬁcient is mild when D/d is larger than 22.2 in the premise of fully developedﬂow in straight ***,a piecewise empir-ical correlation considering the bend diameter and physical property ratio is developed to pre-dict the elbow pressure drop of the serpentine tube and optimize the layout of the cooling tube system on aero-engines.

关键词： Supercritical pressure Aviation fuel Local resistance coefﬁcient Elbow Serpentine tube Empirical correlation