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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 426-430页

作者： Q.Chen H.j.li a.j.li H.M.Han K.Z.li School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 ChinaSchool of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 ChinaSchool of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 ChinaSchool of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 ChinaSchool of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China

Felt base carbon/carbon composites fabricated by super-high pressure impregnation carbonization process (SPIC) were heat treated at high temperature 2773K. The oxidation properties of felt base carbon/carbon composites were investigated at different temperatures (773-1173K), and the microstructures of carbon/carbon composites were studied by SEM and X-ray diffraction. The experimental results showed that the inter-laminar distance of (002) plane (d002) deceased while the microcrystalline stack height (Lc) increased. The oxidation rate of felt base carbon/carbon composites was invari-able at certain temperatures. The oxidation mechanism of carbon/carbon composites changed remarkably at the oxidation temperature 973K. At the initial oxidation stage of carbon/carbon composites, carbon matrix was oxidized much more rapidly than carbon felt.

关键词： carbon/carbon composites high pressure impregnation carbonization high temperature heat treatment oxidation mi-crostructure

Editorial for the Special Issue on Emerging Technology and Advanced Application of Nondestructive Detection for Power Equipment

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Chinese journal of Electrical Engineering 2024年第1期10卷 1-2页

作者： li j. Mei H. li S. Tianjin University China Tsinghua Shenzhen International Graduate School China Lanzhou jiaotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new *** detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the object.

关键词： service Application operation

Precise genome-editing in human diseases:mechanisms,strategies and applications

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1065-1085页

作者： Yanjiang Zheng Yifei li Kaiyu Zhou Tiange li Nathan j.VanDusen Yimin Hua Key Laboratory of Birth Defects and Related Diseases of Women and Children of MOE Department of PediatricsWest China Second University HospitalSichuan UniversityChengduSichuan 610041China Department of Cardiovascular Surgery West China HospitalSichuan UniversityChengduSichuan 610041China Department of Pediatrics Herman B Wells Center for Pediatric ResearchIndiana University School of MedicineIndianapolisIN 46202USA

Precise genome-editing platforms are versatile tools for generating specific,site-directed DNA insertions,deletions,and *** continuous enhancement of these tools has led to a revolution in the life sciences,which promises to deliver novel therapies for genetic *** genome-editing can be traced back to the 1950s with the discovery of DNA’s doublehelix and,after 70 years of development,has evolved from crude in vitro applications to a wide range of sophisticated capabilities,including in vivo ***,precise genome-editing faces constraints such as modest efficiency,delivery challenges,and off-target *** this review,we explore precise genome-editing,with a focus on introduction of the landmark events in its history,various platforms,delivery systems,and ***,we discuss the landmark events in the history of precise ***,we describe the current state of precise genome-editing strategies and explain how these techniques offer unprecedented precision and versatility for modifying the human ***,we introduce the current delivery systems used to deploy precise genome-editing components through DNA,RNA,and ***,we summarize the current applications of precise genome-editing in labeling endogenous genes,screening genetic variants,molecular recording,generating disease models,and gene therapy,including ex vivo therapy and in vivo therapy,and discuss potential future advances.

关键词： precise generating editing

Reply to the note by li Piani et al.

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Defence Technology（防务技术） 2024年第1期31卷 603-606页

作者： T.li Piani j.Weerheijm L.j.Sluys TU Delft Stevinweg 12628 CNDelftthe Netherlands TNO PO Box 452280 AARijswijkthe Netherlands NLDA Faculty of Military Sciences1781 CADen Helderthe Netherlands

In 2017,a ballistic phenomenological model was proposed by the authors of Ref.[1] to numerically simulate the experimental depths of small caliber projectiles impacting walls made of *** opportunity for a new model in the field revealed from the observation that two older models recently used by the authors of Ref.[2] shared a linear relationship between the penetration depth P and the impacting velocity v_(O).

关键词： Penetration Adobe Modeling

Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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journal of Magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.j.li j.H.Chu M.M.li D.N.Zou L.B.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

Convexification of Hybrid AC-DC Optimal Power Flow with line-Commutated Converters

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CSEE journal of Power and Energy Systems 2024年第2期10卷 617-628页

作者： Hongyuan liang Zhigang li j.H.Zheng Q.H.Wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510641China

line-commutated converter (LCC)-based high-voltage DC (HVDC) systems have been integrated with bulk AC power grids for interregional transmission of renewable power. The nonlinear LCC model brings additional nonconvexity to optimal power flow (OPF) of hybrid AC-DC power grids. A convexification method for the LCC station model could address such nonconvexity but has rarely been discussed. We devise an equivalent reformulation for classical LCC station models that facilitates second-order cone convex relaxation for the OPF of LCC-based AC-DC power grids. We also propose sufficient conditions for exactness of convex relaxation with its proof. Equivalence of the proposed LCC station models and properties, exactness, and effectiveness of convex relaxation are verified using four numerical simulations. Simulation results demonstrate a globally optimal solution of the original OPF can be efficiently obtained from relaxed model.

关键词： AC-DC power system convex relaxation linecommutated converter optimal power flow second-order cone programming

A REDUCED ORDER SCHWARZ METHOD FOR NONliNEAR MULTISCALE ELliPTIC EQUATIONS BASED ON TWO-LAYER NEURAL NETWORKS

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journal of Computational Mathematics 2024年第2期42卷 570-596页

作者： Shi Chen Zhiyan Ding Qin li Stephen j.Wright Mathematics Department University of Wisconsin-MadisonMadisonWI 53706USA Department of Mathematics University of California-BerkeleyBerkeley CA 94720USA Mathematics Department and Discovery Institute University of Wisconsin-Madison MadisonWI 53706USA Computer Sciences Department University of WisconsinMadisonWI 53706USA

Neural networks are powerful tools for approximating high dimensional data that have been used in many contexts,including solution of partial differential equations(PDEs).We describe a solver for multiscale fully nonlinear elliptic equations that makes use of domain decomposition,an accelerated Schwarz framework,and two-layer neural networks to approximate the boundary-to-boundarymap for the subdomains,which is the key step in the Schwarz ***,the boundary-to-boundary map requires solution of boundary-value elliptic problems on each *** leveraging the compressibility of multiscale problems,our approach trains the neural network offline to serve as a surrogate for the usual implementation of the boundary-to-boundary *** method is applied to a multiscale semilinear elliptic equation and a multiscale p-Laplace *** both cases we demonstrate significant improvement in efficiency as well as good accuracy and generalization performance.

关键词： Nonlinear homogenization Multiscale elliptic problem Neural networks Do-main decomposition

Semitransparent organic solar cells with high light utilization efficiency and color rendering index

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Science China Chemistry 2024年第7期67卷 2248-2256页

作者： Ni Gao Haijun Bin Shangrong Wu RenéA.j.janssen Yongfang li Laboratory of Advanced Optoelectronic Materials Suzhou Key Laboratory of Novel Semiconductor Materials and DevicesCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China jiangsu Key Laboratory of Advanced Negative Carbon Technologies Soochow UniversitySuzhou 215123China Molecular Materials and Nanosystems&Institute for Complex Molecular Systems Eindhoven University of TechnologyEindhoven 5600 MBthe Netherlands

Semitransparent organic solar cells(ST-OSCs)have garnered considerable attention as promising renewable energy technology for integrating photovoltaics into ***,there is a trade-off between power conversion efficiency(PCE)and average visible transmittance(AVT),which hinders the achievement of a high light utilization efficiency(LUE).In this study,we propose a valuable method to address this challenge by replacing the transparent top electrode,Ag,with a 20 nm layer of *** ST-OSCs based on the 20 nm Au electrode demonstrate superior exciton extraction,more efficient charge collection,and higher color-rendering index(CRI)due to their smoother surface,higher conductivity,and enhanced visible light transmittance,resulting in a significantly higher PCE of 13.67%and an enhanced AVT of 30.17%,contributing to a high LUE of 4.15%.Additionally,optically transparent dielectric layers,applied on the front and back sides of the ST-OSCs to further boost performance,delivered an impressive LUE of 4.93%,with PCE and AVT values reaching 14.44%and 34.12%,***,the champion ST-OSCs also exhibited a favorable CRI value of *** achievements represent the bestperforming ST-OSCs to date with both high LUE and CRI and hold significant implications for the prospective commercialization of ST-OSCs.

关键词： semitransparent organic solar cells power conversion efficiency average visible transmittance light utilization efficiency color-rendering index

Effects of mid-passage gap with a variable surface angle on a turbine vane endwall’s aerothermal and film cooling performances

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Chinese journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu li Kaiyuan ZHANG Zhigang li jun li Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured *** coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this *** endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically *** indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the ***,cooling failure occurs,and the endwall’s thermal load is badly *** film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being *** addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged *** best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side *** the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling Heat transfer Surface angle Mid-passagegap Turbinevane endwall

Males armed with big weapons win fights at limited cost in ant-mimickingjumping spiders

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Current Zoology 2024年第1期70卷 98-108页

作者： Guocheng Yu Boon Hui Wong Christina j.Painting Hongze li Long Yu Zengtao Zhang Shichang Zhang Daiqin li State Key Laboratory of Biocatalysis and Enzyme Engineering and Centre for Behavioral Ecology and Evolution School of Life SciencesHubei UniversityWuhan430062China Departmentof Biological Sciences National University of Singapore14 Science Drive 4Singapore 117543Singapore Te Aka Matuatua School of Science University of WaikatoPrivate Bag 3105Hamilton 3240New Zealand

A core assumption of sexual selection theory is that sexually selected weapons,specialized morphological structures used directly in male con-tests,can improve an individual's reproductive success but only if the bearer can overcome associated costs,the negative effects on the bear-er's fitness ***,recent studies have shown that producing and wielding exaggerated weapons may not necessarily be ***,some traits can be selected for supporting,or compensating for,the expense of producing and wielding such exaggerated weapons.n the ant-mimicking jumping spider Myrmarachne gisti,exaggerated chelicerae are borne only by adult males and not females,showing sexual dimorphism and steep positive allometry with body ***,we determine the potential benefits of bearing exaggerated chelicerae during male contests and explore the potential for costs in terms of prey-capture efficiency and compensation between chelicera size and neighboring trait *** males with longer chelicerae won most of their male-male contests,we found no significant differences in prey-capture effi-ciency between males and females regardless of whether prey was winged or ***'elongated chelicerae thus do not impede their efficiency at capturing ***,we found that the sizes of all neighboring traits are positively correlated with chelicera size,suggesting that these traits may be under correlational *** together,our findings suggest that *** males armed with the exaggerated chelicerae that function as weapons win more fights at limited cost for performance in prey capture and compensate for neighboring structures.

关键词： allometry ant-mimic costs elongated chelicerae threat devices trait compensations