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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 340-346页

作者： Hai-tao Li Bo-ping Zhang Qian Zhang Peng-peng Shang gao-lei zhao School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering Henan University of Science and Technology Luoyang 471003 China

MgO-modified Li0.06（Na0.5K0.5）0.94NbO3O3 （L6NKN） lead-free piezoelectric ceramics were synthesized by normal sintering at a rela- tively low temperature of 1000℃. The crystalline phase, microstructure, and electrical properties of the ceramics were investigated with a special emphasis on the influence of MgO content. The addition of MgO effectively improves the sintembility of the L6NKN ceramics. X-my diffr cfion analysis indicates that the morphotropic phase boundary （MPB） separating orthorhombic and tetragonal phases for the ceramics lies in the range of Mg doping content （x） from 0.3at% to 0.7at%. High electrical properties of the piezoelectric constant （d33=238 pC/N）, planar electromechanical coupling coefficient （kp=41.5%）, relative dielectric constant （εr=905）, and remanent polarization （Pr=38.3 μC/cm2） are obtained from the specimen with x=0.5at%, which suggests that the Li0.06（Na0.5K0.5）0.94Nb（1-2x/5）MgxO3 （x=0.5at%） ceramic is a promising lead-free piezoelectric material.

关键词： lead-flee piezoelectric ceramics sinterability sintering morphotropic phase boundary

Ripening and rot:How ripening processes influence disease susceptibility in fleshy fruits

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Journal of Integrative Plant Biology 2024年第9期66卷 1831-1863页

作者： Shan Li Yu zhao Pan Wu Donald Grierson lei gao State Key Laboratory of Plant Diversity and Specialty Crops Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China Plant and Crop Sciences Division School of BiosciencesUniversity of NottinghamSutton Bonington CampusLoughboroughLE125RDUK Hubei Hongshan Laboratory Wuhan 430070China

Fleshy fruits become more susceptible to pathogen infection when they ripen;for example,changes in cell wall properties related to softening make it easier for pathogens to infect *** need for high-quality fruit has driven extensive research on improving pathogen resistance in important fruit crops such as tomato(Solanum lycopersicum).In this review,we summarize current progress in understanding how changes in fruit properties during ripening affect infection by *** changes affect physical barriers that limit pathogen entry,such as the fruit epidermis and its cuticle,along with other defenses that limit pathogen growth,such as preformed and induced defense *** plant immune system also protects ripening fruit by recognizing pathogens and initiating defense responses involving reactive oxygen species production,mitogen-activated protein kinase signaling cascades,and jasmonic acid,salicylic acid,ethylene,and abscisic acid *** phytohormones regulate an intricate web of transcription factors(TFs)that activate resistance mechanisms,including the expression of pathogenesis-related *** tomato,ripening regulators,such as RIPENING INHIBITOR and NON_RIPENING,not only regulate ripening but also influence fruit defenses against ***,members of the ETHYLENE RESPONSE FACTOR(ERF)family play pivotal and distinct roles in ripening and defense,with different members being regulated by different *** also discuss the interaction of ripening-related and defense-related TFs with the Mediator transcription *** the ripening processes in climacteric and non-climacteric fruits share many similarities,these processes have broad applications across fruiting *** research on the individual contributions of ERFs and other TFs will inform efforts to diminish disease susceptibility in ripe fruit,satisfy the growing demand for high-quality fruit and decrease food waste and related economic losses.

关键词： fleshy fruit pathogen phytohormones ripening transcription factors

Seismic safety assessment with non-Gaussian random processes for train-bridge coupled systems

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 241-260页

作者： zhao Han gao lei Wei Biao Tan Jincheng Guo Peidong Jiang Lizhong Xiang Ping Key Laboratory of Geomechanics and Embankment Engineering of Ministry of Education Hohai UniversityNanjing 210024China School of Civil Engineering Central South UniversityChangsha 410075China

Extensive high-speed railway(HSR)network resembled the intricate vascular system of the human body,crisscrossing *** events,known for their unpredictability,pose a significant threat to both trains and bridges,given the HSR’s extended operational ***,ensuring the running safety of train-bridge coupled(TBC)system,primarily composed of simply supported beam bridges,is *** methods like the Monte Carlo method fall short in analyzing this intricate system ***,efficient algorithm like the new point estimate method combined with moment expansion approximation(NPEM-MEA)is applied to study random responses of numerical simulation TBC *** of the NPEM-MEA’s feasibility is conducted using the Monte Carlo *** analysis confirms the accuracy and efficiency of the method,with a recommended truncation order of four to six for the ***,the influences of seismic magnitude and epicentral distance are discussed based on the random dynamic responses in the TBC *** methodology not only facilitates seismic safety assessments for TBC systems but also contributes to standard-setting for these systems under earthquake conditions.

关键词： train-bridge coupled(TBC)system random vibration new point estimate method(NPEM) seismic safety assessment moment expansion approximation(MEA) non-Gaussian distributions

Beam oscillating parameters on pore inhibition,recrystallization and grain boundary characteristics of laser-arc hybrid welded AZ31 magnesium alloy

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Journal of Magnesium and Alloys 2024年第6期12卷 2489-2502页

作者： Kangda Hao Yongkang gao Lianyong Xu Yongdian Han lei zhao Wenjin Ren Hongyang Jing School of Materials Science and Engineering Tianjin UniversityTianjin300350PR China Tianjin Key Laboratory of Advanced Joining Technology Tianjin300350PR China

Oscillating laser-arc hybrid welding of AZ31B magnesium alloy was carried out,the effects of beam oscillation parameters on pore inhibition,microstructure,grain boundary characteristics and tensile properties were *** results showed that the pore formation can be inhibited with oscillating frequency higher than 75 Hz and radius smaller than 0.5 *** columnar grains neighboring the fusion line can be broken by the beam oscillation behavior,while the grain growth was promoted with the increase of frequency or *** should be noted that the coincidence site lattice(CSL)boundaries were mainlyΣ13b andΣ29 boundaries,which were contributed by{10■2}tensile twins and{11■2}compression twins,*** total fraction of CSL boundaries reached maximum at radius of 0.25 mm and frequency of 75 Hz,which was also confirmed as the optimized *** this case,the elongation rate increased up to 13.2%,12.8%higher than that of the weld without beam ***,the pore formation and inhibition mechanisms were illustrated according to the state of melt flow and keyhole formation,the abnormal growth was discussed basing on secondary recrystallization,and the relationship among the pore formation,grain size,boundary characteristics and weld toughness were finally established.

关键词： Magnesium alloy Laser-arc hybrid welding Beam oscillation Recrystallization Mechanical properties

Microstructure homogeneity and mechanical properties of laser-arc hybrid welded AZ31B magnesium alloy

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Journal of Magnesium and Alloys 2024年第5期12卷 1986-1995页

作者： Yongkang gao Kangda Hao Lianyong Xu Yongdian Han lei zhao Wenjing Ren Hongyang Jing School of Materials Science and Engineering Tianjin UniversityTianjin 300350PR China Tianjin Key Laboratory of Advanced Joining Technology Tianjin 300350PR China

Laser-arc hybrid welding of AZ31B magnesium alloy was carried out,the effects of welding parameters on weld formation,microstructure homogeneity and mechanical properties were *** results showed that laser-arc hybrid welding was beneficial to improve the weld formation of magnesium alloy by inhibiting the defect of undercut and *** weld microstructure was mainly columnar grains neighboring the fusion line and equiaxed grains at the weld *** was interesting that the grain size at the upper arc zone was smaller than that at the lower laser zone,with the difference mainly affected by laser power rather than welding current and welding *** welding parameters were optimized as laser power of 3.5 kW,welding current of 100 A and welding speed of 1.5 m/*** this case,the weld was free of undercut and pores,and the tensile strength and elongation rate reached 252 MPa and 11.2%,***,the microstructure homogeneity was illustrated according to the heat distribution,and the evolution law of tensile properties was discussed basing on the weld formation and microstructure characteristics.

关键词： Magnesium alloy Laser-arc hybrid welding Microstructure homogeneity Mechanical properties

Spatial compartmentalization and temporal stability of associated microbiota in Pacific oyster Crassostrea gigas

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Journal of Oceanology and Limnology 2024年第4期42卷 1348-1358页

作者： Qiang FU Zichao YU Junyan zhao lei gao Ning KONG Lingling WANG Linsheng SONG Liaoning Key Laboratory of Marine Animal Immunology and Disease Control Dalian Ocean UniversityDalian 116023China Functional Laboratory of Marine Fisheries Science and Food Production Processes Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519000China Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control Dalian Ocean UniversityDalian 116023China

The Pacific oyster Crassostrea gigas,one of the most exploited molluscs in the world,has suffered from massive mortality in recent decades,and the occurrence mechanisms have not been well *** this study,to reveal the relationship of associated microbiota to the fitness of oysters,temporal dynamics of microbiota in the gill,hemolymph,and hepatopancreas of *** during April 2018-January 2019 were investigated by 16 S rRNA gene *** microbiota in *** exhibited tissue heterogeneity,of which Spirochaetaceae was dominant in the gill and hemolymph while Mycoplasmataceae enriched in the ***-occurrence network demonstrated that the gill microbiota exhibited higher inter-taxon connectivity while the hemolymph microbiota had more *** richness(Chao 1 index)and diversity(Shannon index)of microbial community in each tissue showed no significant seasonal variations,except for the hepatopancreas having a higher richness in the ***,beta diversity analysis indicated a relatively stable microbiota in each tissue during the sampling period,showing relative abundance of the dominant taxa exhibiting temporal *** indicate that the microbial community in *** showed a tissue-specific stability with temporal dynamics in the composition,which might be essential for the tissue functioning and environmental adaption in *** work provides a baseline microbiota in *** and is helpful for the understanding of host-microbiota interaction in oysters.

关键词： Pacific oyster associated microbiota spatial compartmentalization temporal stability

Towards catalytic reactions of Cu single-atom catalysts:Recent progress and future perspective

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Chinese Chemical Letters 2024年第2期35卷 197-207页

作者： Yitao zhao lei Tao Jiangsu Province Engineering Research Center of Special Functional Textile Materials Changzhou Vocational Institute of Textile and GarmentChangzhou 213164China Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterSchool of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China

One of the urgent and challenging topics in diversified sustainable energy conversion is the development of high-performance,low-cost,and well durable *** single-atom catalysts(SACs)have become promising catalysts for diversified sustainable energy conversion due to their capability to maximize the utilization efficiency,acquire modulated electronic structure and optimized binding strength with *** this review,we have provided an interview of the recent progress achieved in the field of electrocatalysis,photocatalysis,and heterogeneous reaction based on Cu *** by this review,we have summarized some advanced synthetic strategies for the construction of Cu ***,the performance-improving strategies are discussed in terms of the coordination environments of the reaction center,reaction mechanism and selectivity,based on free energy diagram and electron structure ***,the remaining issues,challenges,and opportunities of Cu SACs are also provided,affording a perspective for future *** review not only offers us a deep understanding on the catalytic mechanism of Cu SACs for energy conversion,but also encourages more endeavors in prompting their practical application.

关键词： Cu SACs Energy conversion Catalysis Coordination environment

Reinforced SnO_(2) tensile-strength and“buffer-spring”interfaces for efficient inorganic perovskite solar cells

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Carbon Energy 2024年第6期6卷 282-291页

作者： Yuanyuan zhao lei gao Qiurui Wang Qiang Zhang Xiya Yang Jingwei Zhu Hao Huang Jialong Duan Qunwei Tang College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdaoChina Institute of New Energy Technology College of Information Science and TechnologyJinan UniversityGuangzhouChina College of Materials Science and Engineering Sichuan UniversityChengduChina Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials School of ResourcesEnvironment and MaterialsGuangxi UniversityNanningChina Institute of Carbon Neutrality College of Chemical and Biological EngineeringShandong University of Science and TechnologyQingdaoChina

Suppressing nonradiative recombination and releasing residual strain areprerequisites to improving the efficiency and stability of perovskite solar cells(PSCs).Here,long-chain polyacrylic acid(PAA)is used to reinforce SnO_(2)film and passivate SnO_(2)defects,forming a structure similar to“reinforcedconcrete”with high tensile strength and fewer ***,PAA is also introduced to the SnO_(2)/perovskite interface as a“buffer spring”torelease residual strain,which also acts as a“dual-side passivation interlayer”to passivate the oxygen vacancies of SnO_(2)and Pb dangling bonds in *** a result,the best inorganic CsPbBr_(3)PSC achieves a championpower conversion efficiency of 10.83%with an ultrahigh open-circuit voltageof 1.674 *** unencapsulated PSC shows excellent stability under 80%relative humidity and 80℃over 120 days.

关键词： charge recombination defect passivation inorganic perovskite solar cells interfacial modification strain relaxation

Evolution of inclusions in vacuum induction melting of superalloys containing 70%return material

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Journal of Iron and Steel Research International 2024年第3期31卷 719-728页

作者： Jin-guo gao Shu-lei Yang Shu-feng Yang Jing-she Li Wei Liu Meng-jing zhao An-ren Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Metallurgical and Building Materials Business Department China International Engineering Consulting CorporationBeijing 100048China

The variation law of inclusions type and size in the vacuum induction melting process and ingot of Ni-based superalloy containing 70%return material was studied by industrial test sampling,and the mechanism of inclusions formation was analyzed with thermodynamic *** results show that there are mainly two types of composite inclusions in the vacuum induction melting of Ni-based superalloys,which are nitride-and oxide-based composite inclusions,like Al_(2)O_(3)-SiO_(2)-Cr_(2)O_(3),TiN-(Mo,Nb)C,*** type and proportion of inclusions from the center to the edge of the vacuum induction ingot did not change *** number density of inclusions from the center to the edge of the ingot varied less,and the size of inclusions became smaller from the center to the *** addition,thermodynamic calculations show that oxides(M_(2)O_(3))are present in the liquid phase and mainly contain Al,Ti,Cr,Fe and O *** nitride consists mainly of Ti and N and contains small amounts of Cr,C,Nb,and Mo *** is consistent with the results of industrial *** the temperature decreases,the precipitation phases such as M_(2)O_(3),MN,γ,MC,δ,γ'andμphases are gradually precipitated,where oxides and nitrides are present in the liquid *** contents of O and N elements are the main influencing factors for the inclusions content and precipitation temperature;when the nitrogen content is reduced to below 0.0015%,it can make MN precipitate below the liquid-phase line.

关键词： Ni-based superalloy Vacuum induction melting Return material Inclusion Thermodynamic

Deep kernel extreme learning machine classifier based on the improved sparrow search algorithm

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The Journal of China Universities of Posts and Telecommunications 2024年第3期31卷 15-29页

作者： zhao Guangyuan lei Yu School of Automation Xi'an University of Posts and TelecommunicationsXi'an 710000China

In the classification problem,deep kernel extreme learning machine(DKELM)has the characteristics of efficient processing and superior performance,but its parameters optimization is *** improve the classification accuracy of DKELM,a DKELM algorithm optimized by the improved sparrow search algorithm(ISSA),named as ISSA-DKELM,is proposed in this *** at the parameter selection problem of DKELM,the DKELM classifier is constructed by using the optimal parameters obtained by ISSA *** order to make up for the shortcomings of the basic sparrow search algorithm(SSA),the chaotic transformation is first applied to initialize the sparrow ***,the position of the discoverer sparrow population is dynamically adjusted.A learning operator in the teaching-learning-based algorithm is fused to improve the position update operation of the ***,the Gaussian mutation strategy is added in the later iteration of the algorithm to make the sparrow jump out of local *** experimental results show that the proposed DKELM classifier is feasible and effective,and compared with other classification algorithms,the proposed DKELM algorithm aciheves better test accuracy.

关键词： deep kernel extreme learning machine(DKELM) improved sparrow search algorithm(ISSA) classifier parameters optimization