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The unitary subgroups of group algebras for a class of finite 2-groups with the derived subgroup of order 2

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Science China Mathematics 2024年第9期67卷 1989-2018页

作者： yulei Wang Heguo liu Department of Mathematics Henan University of TechnologyZhengzhou 450001China Department of Mathematics Hainan UniversityHaikou 570228China

Let p be a prime and F be a finite field of characteristic *** that FG is the group algebra of the finite p-group G over the field *** V(FG)denote the group of normalized units in FG and let V_(*)(FG)denote the unitary subgroup of V(FG).If p is odd,then the order of V_(*)(FG)is|F|^((|G-1)/2).However,the case p=2 still is *** this paper,the order of V*(FG)is computed when G is a nonabelian 2-group given by a central extension of the form 1→z_(2^(n))×z_(2^(m))→G→z_(2)×…×z_(2)→1 and G'≌z_(2),n,m≥***,a conjecture is confirmed,i.e.,the order of V_(*)(FG)can be divisible by|F|^(1/2(|G|+|Ω1(G)|)-1),where Ω_(1)(G)={g∈G|g^(2)=1}.

关键词： normalized unit unitary subgroup inner abelian p-group central extension

Schisanhenol ameliorates non-alcoholic fatty liver disease via inhibiting miR-802 activation of AMPK-mediated modulation of hepatic lipid metabolism

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Acta Pharmaceutica Sinica B 2024年第9期14卷 3949-3963页

作者： Li B. Xiao Q. zhao H. zhang J. yang C. zou y. zhang B. liu J. Sun H. liu H. State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Medicinal Plant Development Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100193 China Institute of Basic Medical Sciences Chinese Academy of Medical Sciences Department of Pathophysiology Peking Union Medical College Beijing 100005 China

Non-alcoholic fatty liver disease (NAFLD), characterized by hepatic steatosis, is a common metabolic liver disease worldwide. Currently, satisfactory drugs for NAFLD treatment remain lacking. Obesity and diabetes are the leading causes of NAFLD, and compounds with anti-obesity and anti-diabetic activities are considered suitable candidates for treating NAFLD. In this study, biochemical and histological assays revealed that a natural lignan schisanhenol (SAL) effectively decreased lipid accumulation and improved hepatic steatosis in free fatty acid (FFA)-treated HepG2 cells and high-fat diet (HFD)-induced NAFLD mice. Further, molecular analyses, microRNA (miRNA)-seq, and bioinformatics analyses revealed that SAL may improve NAFLD by targeting the miR-802/adenosine monophosphate-activated protein kinase (AMPK) pathway. Liver-specific overexpression of miR-802 in NAFLD mice significantly impaired SAL-mediated liver protection and decreased the protein levels of phosphorylated (p)-AMPK and PRKAB1. Dual-luciferase assay analysis further confirmed that miR-802 inhibits hepatic AMPK expression by binding to the 3' untranslated region of mouse Prkab1 or human PRKAA1. Additionally, genetic silencing of PRKAA1 blocked SAL-induced AMPK pathway activation in FFA-treated HepG2 cells. The results demonstrate that SAL is an effective drug candidate for treating NAFLD through regulating miR-802/AMPK-mediated lipid metabolism. © 2024 The Authors

关键词： AMPK Hepatic steatosis Lipid metabolism miR-802 Non-alcoholic fatty liver disease PPARα Schisanhenol SREBP-1c

The preparation and performance analysis of zirconium-modified aluminum phosphate-based high-temperature(RT-1500℃)resistant adhesive for joining alumina in extreme environment

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Journal of Advanced Ceramics 2024年第7期13卷 911-932页

作者： Jingxuan liu yange Wan Bo Xiao Jiancun Li zhanming Hu Ruoyu zhang Xiaoxia Hu Jiachen liu Guoshuai Cai Hongli liu Mingchao Wang College of Science Civil Aviation University of ChinaTianjin 300300China Department of Safety Engineering Civil Aviation University of ChinaTianjin 300300China Binzhou Beicheng Construction Engineering Materials Testing Co. Ltd.Binzhou 256602China Department of Aviation Engineering Civil Aviation University of ChinaTianjin 300300China School of Materials and Engineering Key Lab of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China

High-temperature-resistant adhesives are critical materials in the aerospace *** zirconium-modified aluminum phosphate-based adhesives developed in this work had the advantage of adjustable thermal expansibility,achieving a high matching of coefficient of thermal expansion(CTE)with *** introduction of zirconium can significantly improve the thermal stability of the adhesive matrix,and the zr/Al ratio substantially affects the various reaction processes inside the adhesive,especially the types of zirconium-containing *** of the zirconium-containing compounds in the A7z3 adhesive were zrO2 only when the mass ratio of zirconium hydroxide to aluminum hydroxide was 3:7,which was the key reason why it had the highest *** room-temperature bonding strength of A7z3 after heat treatment at 1500℃reached 67.2 *** pretreatment at 1500℃,the high-temperature bonding strength of A7z3 was greater than 50 MPa in the range of(room temperature)RT-1000℃.After 40 thermal cycles between RT and 1500℃,the bonding strength still reached 10 *** bonding occurred at temperatures below 1000℃,while chemical bonding dominated above 1000℃based on the generation of Al5BO9 and mullite at the interfaces.

关键词： high-temperature-resistant adhesive thermal expansion property zirconium-modified aluminum phosphate bonding performance thermal cycling bonding mechanism

Defects in the grain interiors of 3 mol%yttria-stabilized tetragonal zirconia polycrystal ceramics with 0.25 wt%alumina

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Journal of Advanced Ceramics 2024年第4期13卷 469-477页

作者： yan Xiong Lian Luo yao Cheng zhi liu Qi liu Weimin Wang Wei Ji School of Materials&Chemical Engineering Hubei Province Key Laboratory of Green Materials for Light IndustryHubei University of TechnologyWuhan 430068China Fujian Institute of Research on the Structure of Mater Chinese Academy of SciencesFuzhou 350002China Jiangxi Provincial Engineering Research Center for Multifunction zirconia Materials Jiangxi Size Materials Co.Ltd.Jiujiang 332500China State Key Laboratory of Advance Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The presence of high-density defects is rarely observed in bulk 3 mol%yttria-stabilized tetragonal zirconia polycrystal(3y-TzP)ceramics obtained through conventional pressureless *** the present work,fine-grained dense 147 nm 3y-TzP ceramics were prepared by pressureless sintering of commercial 0.25 wt%alumina-doped zirconia powders at 1300℃.A novel discovery was reported in which large amounts of defects were present in the grain interiors of the *** phenomenon was further examined using three types of powder samples,and the reasons for defect formation were investigated by microstructural characterization using high-resolution transmission electron microscopy(HRTEM)analysis and Rietveld *** results confirmed the essential dependence of the defect formation on the alumina *** authors attributed the defect formation to the significant difference in ionic radii of the solvent and solute during the dissolution of alumina into the zirconia *** sintering kinetics were proposed to be enhanced by the presence of substantial defects,which consequently favored the low-temperature sintering of the alumina-doped zirconia ceramics.

关键词： 3 mol%yttria-stabilized tetragonal zirconia polycrystal(3y-TzP)ceramics alumina addition microstructure defect

High toughness and CMAS resistance of REAlO_(3)/RE_(2)zr_(2)O_(7)(RE=La,Nd,Sm,Eu,Gd,and Dy)composites with eutectic composition for thermal barrier coatings

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Journal of Advanced Ceramics 2024年第6期13卷 800-809页

作者： zijian zhang Jian Sun Guanghua liu yi Han Wei liu yi Li Wei Wang Xiangyang liu Peng zhang Wei Pan Chunlei Wan State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China China United Gas Turbine Technology Co. Ltd.Beijing 100015China College of Mathematics and Physics Beijing University of Chemical TechnologyBeijing 100029China College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China

Although rare earth zirconates(RE_(2)zr_(2)O_(7))have garnered attention as viable candidates for thermal barrier coatings(TBCs),they suffer from low fracture toughness and accelerated calcium–magnesium–alumina–silicate(CMAS)melt corrosion at high service temperatures,which impedes their practical *** this work,we developed a series of REAlO_(3)/RE_(2)zr_(2)O_(7)(RE=La,Nd,Sm,Eu,Gd,and Dy)composites with a eutectic composition that not only significantly enhanced the fracture toughness by more than 40%relative to that of RE_(2)zr_(2)O_(7)but also exhibited improved resistance to CMAS *** increase in toughness arises from multiple mechanisms,such as ferroelastic toughening,fine-grain strengthening,and residual stress toughening,all of which trigger more crack defects and energy ***,the CMAS penetration depth of the REAlO_(3)/RE_(2)zr_(2)O_(7)composites is approximately 36%lower than that of RE_(2)zr_(2)O_(7).Al–O constituents in composites can capture CaO,SiO_(2),and MgO in CMAS melts and increase their viscosity,resulting in enhanced CMAS corrosion *** thermophysical properties of the REAlO_(3)/RE_(2)zr_(2)O_(7)composites were also investigated,and their coefficient of thermal expansion and thermal conductivity are comparable to those of 7–8 wt%y_(2)O_(3)partially stabilized zrO2(ySz),indicating their potential as TBC materials.

关键词： fracture toughness thermal property calcium-magnesium-alumina-silicate(CMAS)corrosion REAlO_(3)/RE_(2)zr_(2)O_(7) eutectic composition

Activation of dislocations in Mg with solute y

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Journal of Magnesium and Alloys 2024年第3期12卷 1045-1053页

作者： Alireza Maldar Leyun Wang Boyu liu Wenjun liu zhaohui Jin Bijin zhou Xiaoqin zeng National Engineering Research Center of Light Alloy Net Forming Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049China Advanced Photon Source Argonne National LaboratoryIL 60439USA Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016China School of Mechanical Engineering Suzhou University of Science and TechnologySuzhou 215009China

Mg-y cast alloy shows excellent ductility(elongation to failure>15%)compared with pure Mg and commercial Mg cast *** monitoring the microstructure evolution during an in situ tensile test of a Mg-2.5 wt%y alloy,we identify the activation of prismaticslip,which is rare in *** X-ray micro-beam Laue diffraction(μ-Laue)and transmission electron microscopy revealed the morphology of prismaticslip bands and individual*** functional theory and molecular dynamics calculations indicate that solute y can significantly reduce the stacking fault energy(SFE)alongdirection on prismatic plane in Mg lattice and thus facilitate the nucleation ofdislocations during *** presence of freedislocations in the Mg lattice can also lead to nucleation of{10–12}twins even under unfavorable geometric conditions.

关键词： alloy microstructure ductility

Relative Broken Family Sensitivity

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2297-2306页

作者： zhuo Wei liu Tao yU Department of Mathematics Shantou UniversityShantou 515063P.R.China

Letπ:(X,T)→(y,S)be a factor map between two topological dynamical systems,and F_(a) Furstenberg family of *** introduce the notion of relative broken *** Fs(***,Finf)be the families consisting of all syndetic subsets(*** upper Banach density subsets,infinite subsets).We show that for a factor mapπ:(X,T)→(y,S)between transitive systems,πis relatively broken F-sensitive for F=Fs or Fpubd if and only if there exists a relative sensitive pair which is an F-recurrent point of(R_(π),T^((2)));is relatively broken Finf-sensitive if and only if there exists a relative sensitive pair which is not *** a factor mapπ:(X,T)→(y,S)between minimal systems,we get the structure of relative broken F-sensitivity by the factor map to its maximal equicontinuous factor.

关键词： Relative sensitivity recurrent points Furstenberg family relative sensitive pairs maximal equicontinuous factor

From non-carbon host toward carbon-free lithium-sulfur batteries

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Nano Research 2024年第3期17卷 1337-1365页

作者： yanqi Feng Hui liu Qiongqiong Lu School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi’an 710021China Institute of Materials Henan Key Laboratory of Advanced Conductor MaterialsHenan Academy of SciencesZhengzhou 450046China Leibniz Institute for Solid State and Materials Research(IFW)Dresden e.V. Helmholtzstraβe 2001069 DresdenGermany School of Materials&Environment Engineering Chengdu Technological UniversityChengdu 611730China

Lithium-sulfur(Li-S)batteries with advantages of high energy densities(2600 Wh·kg^(-1)/2800 Wh·L^(-1))and sulfur abundance are regarded as promising candidates for next-generation high-energy ***,the conventional carbon host used in sulfur cathodes suffers from poor chemical adsorption towards Li-polysulfides(LPS)in liquid electrolyte and sluggish redox kinetics,leading to low capacity and rate ***,carbon host used in Li metal anode with the intrinsic property of poor lithiophilicity and high Li-nucleation barrier gives rise to uncontrollable dendrite growth and further battery ***,non-carbon hosts with chemical adsorption toward LPS and catalytic activity for accelerating LPS redox conversion as well as lithiophilic property for guiding uniform Li deposition are proposed and demonstrated a high efficiency in both sulfur cathodes and Li metal *** this review,the principle and challenges of Li-S batteries are first presented,then recent work using non-carbon hosts in Li-S batteries is summarized comprehensively,and the mechanism of non-carbon host in improving sulfur utilization and stabilizing Li metal anode is discussed in ***,remaining challenges and outlook on the implementation of non-carbon host for practical carbon-free Li-S batteries are also provided.

关键词： sulfur cathode Li metal anode polysulfides adsorption catalytic effect Li dendrite carbon-free lithium-sulfur batteries

Recent progress in side chain engineering of y-series non-fullerene molecule and polymer acceptors

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Science China Chemistry 2024年第3期67卷 788-805页

作者： Li Tian Chunchen liu Fei Huang School of Materials Science and Engineering Henan University of TechnologyZhengzhou 450001China Institute of Polymer Optoelectronic Materials and Devices State Key Laboratory of Luminescent Materials and DevicesSouth China University of TechnologyGuangzhou 510640China

Organic solar cells(OSCs) have drawn considerable attention in the last decade due to the great potential of light weight,flexibility, and low-cost solution processing. Particularly, y-series non-fullerene acceptors(NFAs) including small molecular acceptors(SMAs) and polymerized small molecular acceptors(PSMAs) have become research hot spots due to their excellent power conversion efficiency. Side chain engineering is crucial to adjust the solubility and crystallinity of NFAs, which will significantly affect the morphology of active layers and the efficiency of OSCs. However, the understanding of side chain engineering on NFAs is still limited and lacks a systematic review. This review aims to provide a brief summary of the recent developments in side chain engineering of NFAs, with a special focus on the design and application of y-series SMAs and PSMAs for high-efficiency non-fullerene organic solar cells(NF-OSCs). In addition, the review also points out challenges and provides useful guidance regarding side chain regulation for y-series NFAs.

关键词： organic solar cell y-series non-fullerene acceptors side chain engineering