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Applied Mathematics and Mechanics(English Edition) 2020年第2期41卷 193-206页

作者： X.wANG w.t.ANG H.FAN School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

the current work models a weak(soft) interface between two elastic materials as containing a periodic array of micro-crazes. the boundary conditions on the interfacial micro-crazes are formulated in terms of a system of hypersingular integro-differential equations with unknown functions given by the displacement jumps across opposite faces of the micro-crazes. Once the displacement jumps are obtained by approximately solving the integro-differential equations, the effective stiffness of the micro-crazed interface can be readily computed. the effective stiffness is an important quantity needed for expressing the interfacial conditions in the spring-like macro-model of soft interfaces. Specific case studies are conducted to gain physical insights into how the effective stiffness of the interface may be influenced by the details of the interfacial micro-crazes.

关键词： micromechanical modeling micro-crazed interface effective stiffness coefficient hypersingular integro-differential equation

A Global weizsacker mass model with relativistic mean field shell correction

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Chinese Physics C 2022年第10期46卷 163-169页

作者： w.Zhang Z.Y.Li w.Gao t.t.Sun School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China Guangxi Key Laboratory of Nuclear Physics and Nuclear technology Guangxi Normal UniversityGuilin 541004China

A relativistic weizsacker mass model is proposed based on the single-particle levels and ground state deformations obtained in axial deformed relativistic mean field *** density functional of relativistic mean field theory is chosen as DD-LZ1,which can partially remove spurious shell *** with the fourth weizsacker-Skyrme mass model,the proposed model provides shell correction energies that exhibit wide spreading,and the root-mean-square mass deviation is 1.353 *** improvement is in progress.

关键词： mass model relativistic mean field macroscopic-microscopic model

NOISE CONtROL IN tHE wEStERN wORLD OVER tHE PASt 2000 YEARS

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Chinese Journal of Acoustics 1988年第2期7卷 176-182页

作者： t.F.w.Embleton Division of Physics National Research Council Canada

the histroical courcse concerning some noise events and its control over the past 2000 years in North America and parts of western Europe is described.

关键词： NOISE CONtROL IN tHE wEStERN wORLD OVER tHE PASt 2000 YEARS

Response of endemic afroalpine rodents to the removal of livestock grazing pressure

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Current Zoology 2011年第6期57卷 741-750页

作者： Flavie VIAL David w. MACDONALD Daniel t. HAYDON Boyd Orr Centre for Population and Ecosystem Health Institute of Biodiversity Animal Health and Comparative Medicine College of Medical Veterinary and Life Sciences University of Glasgow Glasgow G12 8QQ UK. wildlife Conservation Research Unit Zoology Department University of Oxford The Recanati-Kaplan Centre Tubney House Tubney OX13 5QL UK.

the Bale Mountains of Ethiopia represent the world＇s largest continuous extent of afroalpine habitat. with a peak combined density of over 8000 individuals/km2, the endemic giant mole rat tachyoryctes macrocephalus, Blick＇s grass rat Arvi- canthis blicki and the brush-furred mouse Lophuromys melanonyx are the dominant wild herbivores within this ecosystem and may be affected by the presence of high densities of domestic livestock. the purpose of this study was to establish whether these endemic rodent populations could respond to the removal of grazing pressure inside three 0.25 hectare livestock exclosures （paired with grazed control plots） and to determine whether such response was mediated through concomitant changes in the vegetation structure. we hypothesised that livestock grazing negatively affects endemic rodent populations through competition or increased predation risk and we predicted an increase in rodent biomass following the removal of grazing pressure. we found no evidence of rodent populations responding to the removal of livestock after fourteen months. the short-term nature of the ex- perimental design, environmental fluctuations and the ecosystem＇s inherent stochasticity may explain the apparent lack of a sig- nificant response. However, while this study is inconclusive, it emphasises the need for more long-term experimental investiga- tions to assess the effects of domestic grazers on vegetation and on dependent communities. the effects of rapidly increasing livestock numbers in the Bale Mountains will require continued close monitoring of vegetation and endemic animal communities as the afroalpine is altered by external biotic and abiotic forces .

关键词： Afroalpine Bale Mountains Exclosures Livestock grazing Murid rodents

Assessing impacts of energy storage on resilience of distribution systems against hurricanes

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 731-740页

作者： Hieu t.NGUYEN John w.MUHS Masood PARVANIA Department of Electrical and Computer Engineering University of UtahSalt Lake CityUT 84112USA

this paper develops a comprehensive framework to analyze the impact of energy storage on improving the resilience of distribution systems against *** paper first develops a spatio-temporal model of progressing hurricane when making landfall that can be used to anticipate outage scenarios caused by the gust-wind *** optimization model is then developed for optimizing the operation of distribution systems during hurricane that captures both pre-outage and post-outage network operation *** simulations are performed on the modified IEEE 33-bus distribution system with real hurricane data in Houston to demonstrate the effectiveness of the proposed model.

关键词： Resilience Hurricane Energy storage Distribution system

A critical review on natural compounds interacting with the plant plasma membrane H^(+)-AtPase and their potential as biologicals in agriculture

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Journal of Integrative Plant Biology 2022年第2期64卷 268-286页

作者： Nanna w.Havshφi Anja t.Fuglsang Department of Plant and Environmental Sciences Section for Transport BiologyUniversity of CopenhagenFrederiksbergCopenhagenDK-1871 Denmark

the plant plasma membrane(PM)H^(+)-AtPase is an essential enzyme controlling plant growth and *** is an important factor in response to abiotic and biotic stresses and is subject to tight *** are in demand for new sustainable natural growth regulators and as a key enzyme for regulation of transport into the plant cell the PM H^(+)-AtPase is a potential target for *** this review,we have evaluated the known non-protein natural compounds with regulatory effects on the PM H^(+)-AtPase,focusing on their mechanism of action and their potential as biologicals/growth regulators in plant production of future sustainable agriculture.

关键词： biologicals cyclic-lipodepsipeptides H^(+)-AtPase H+pump natural compounds phosphatidylinositol plasma membrane pore forming compound tenuazonic acid

Application of kernel ridge regression in predicting neutron-capture reaction cross-sections

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Communications in theoretical Physics 2022年第9期74卷 98-104页

作者： t X Huang X H wu P w Zhao State Key Laboratory of Nuclear Physics and technology School of PhysicsPeking UniversityBeijing 100871China

this article provides the first application of the machine-learning approach in the study of the cross-sections for neutron-capture reactions with the kernel ridge regression(KRR)*** is found that the KRR approach can reduce the root-mean-square(rms)deviation of the relative errors between the experimental data of the Maxwellian-averaged(n,γ)cross-sections and the corresponding theoretical predictions from 69.8%to 35.4%.By including the data with different temperatures in the training set,the rms deviation can be further significantly reduced to 2.0%.Moreover,the extrapolation performance of the KRR approach along different temperatures is found to be effective and reliable.

关键词： kernel ridge regression machine learning neutron-capture reaction

Phase Formation and Magnetic Properties of Nanocomposite Nd-Fe-B Adjusted by Small Amount of Dy and Co

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Journal of Rare Earths 2004年第Z2期22卷 89-94页

作者： t S Jang t w Lim H S Aum D H Lee M B Kim Division of Materials and Chemical Engineering Sun Moon UniversityKorea Division of Materials and Chemical EngineeringSun Moon UniversityKorea Division of Mechanical EngineeringSun Moon University 100 Kalsan LiTangjung MyonAsan CityChoongnam 336-708Korea Division of Materials and Chemical EngineeringSun Moon UniversityKorea Division of Materials and Chemical EngineeringSun Moon UniversityKorea

In order to improve and stabilize the magnetic properties of nanocomposite Nd2Fe14B/α-Fe magnetic alloys by a compositional adjustment, small amount of Dy and/or Co was added to Nd9Fe84B7 alloys. DtA analysis on the amorphous of the alloys took place as the soft magnetic phases were crystallized, and then the hard magnetic Nd2Fe14B was precipitated from them. while α-Fe and a metastable 1:7 (tbCu7-type) phase were formed simultaneously in Dy and Co-free alloys, they were crystallized separately at different temperatures after Dy or Co was added. this phase separation occurred more clearly in the Dy-treated alloys and the other soft magnetic phase Fe3B was also stabilized by Dy and/or Co. the 1: 7 phase that was stabilized by Dy and/or Co was not eliminated at 700 ℃, decreasing magnetic properties of the alloys. It was eventually disappeared above 725 ℃, but Fe3B was not eliminated even at 750 ℃ when Dy was added more than 0.5 at% or Co was added more than 2.0 at%. Amount of Nd2Fe14B in the alloys tended to increase as Dy addition increased,whereas Co addition did not lead to any appreciable change in the ratio of α-Fe and Nd2Fe14B. Moreover, Dy addition apparently increased coercivity of an alloy while Co addition had a beneficial effect on remanence. the grains in the Dytreated alloys were usually finer than those in the Co-treated alloys. the grain size of both α-Fe and Nd2Fe14B in the alloys exhibiting mr ≥ 0.72 was in the range of 20 ～ 40 nm or even larger 50 nm, which is larger than the theoretical optimum size ( ～ 10 nm). typical magnetic properties obtained from a Nd7.5Dy1.5Fe82.5Co1.5B7 alloy annealed for 12 min at 725 ℃were iHc=4.85 kOe, Br= 11.32 kG, (BH)max = 15.73 MGOe, and mr=0.73.

关键词： nanocomposite Nd-Fe-B magnetic properties remanence coercivity

Bacterial inclusion bodies function as vehicles for dendritic cell-mediated t cell responses

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Cellular & Molecular Immunology 2020年第4期17卷 415-417页

作者： Sjoerd t.t.Schetters wouter S.P.Jong Laura J.w.Kruijssen H.B.van den Berg van Saparoea Steef Engels wendy w.J.Unger Diane Houben Joke M.M.den Haan Joen Luirink Yvette van Kooyk Department of Molecular Cell Biology and Immunology Amsterdam UMCLocation VUmcAmsterdamThe Netherlands Abera Bioscience AB SolnaSweden Laboratory of Pediatrics Division of Pediatric Infectious Diseases and ImmunologyErasmus MC-Sophia Children’s HospitalRotterdamThe Netherlands Department of Molecular Cell Biology Section Molecular MicrobiologyFaculty of ScienceVU UniversityAmsterdamThe Netherlands

Immunogenic antigens for vaccination are often created through the production of recombinant proteins using Escherichia coli.1 As a side product,aggregates called inclusion bodies(IBs)are formed,containing largely misfolded forms of the overexpressed recombinant protein.2 the effect of IBs on the immune system and whether they can be used as effective vaccine products remain *** non-native conformation of proteins upon accumulation in IBs abrogates their use as vaccines aimed at generating high-affinity antibodies.3 However,IBs exhibit unique properties,including mechanical and thermal stability due to their intrinsic particulate nature,biocompatibility,high antigenic content,low toxicity and relative resistance to *** characteristics make IBs attractive as an antigenic vaccine formulation for t cell responses to linear *** IBs can trigger adaptive cellular responses initiated via uptake by dendritic cells for presentation to t cells is unknown.

关键词： vaccine attractive initiated

Frequency Veering of Rotating Metal Porous twisted Plate with Cantilever Boundary Using Shell theory

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Acta Mechanica Solida Sinica 2022年第2期35卷 282-302页

作者： Y.Y.Liu Y.X.Hao w.Zhang L.t.Liu S.w.Yang Y.t.Cao College of Mechanical Engineering Beijing Information Science and Technology UniversityBeijing 100192China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124China

the frequency veering of a metal porous rotating cantilever twisted plate with twist angle and stagger angle is *** porous materials may have the characteristics of gradient or uniform distribution along the thickness *** on the classical shell theory,considering the influence of centrifugal force produced by high-speed rotation,the free vibration equations of a rotating cantilever twisted plate are *** the polynomial function and Rayleigh-Ritz method,the natural frequencies and mode shapes of the metal porous cantilever twisted plate in both static and rotating states are *** accuracy of the present theory and calculation results is confirmed by a comparison between them and the results available from the literature and those obtained from *** influences of the thickness ratio,porosity,twist angle,stagger angle and rotational velocity on the frequency veering and mode shape shift of the rotating cantilever twisted plate with porous material under three different distributions are *** should be mentioned that the frequency veering accompanied by mode shape shift occurs in both static and dynamic states.

关键词： Frequency veering Rotating twisted plate Cantilever boundary Metal porous