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Journal of Iron and Steel Research International 2017年第4期24卷 475-482页

作者： juan-juan liu Qing Wang Kang Sun Sebastien Gravier Jean-jacque Blandin Bao-an Sun Jian lu laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghai 200072China department of Mechanical and Biomedical Engineering City University of Hong Kong Science et Ingenierie des Matériaux et des Procédés(SIMAP) University of Grenoble/CNRSGrenoble-INPSaint-Martin d'Heres Cedex 38402France

The serrated plastic flow,microstructure and residual stress of a Zr_（55）Cu_（30）Ni_5Al_（10） bulk metallic glass（BMG）undergone surface mechanical attrition treatment（SMAT）have been investigated by a combination of compression tests with scanning electron microscopy（SEM）,high resolution transmission electron microscopy（HRTEM）and the incremental hole-drilling strain-gage *** is found that SMAT leads to various microstructural modifications and residual stress distribution in the surface layers of the Zrbased BMG due to the mechanically-induced nanocrystallization and generation of shear *** a result,the BMG alloy exhibits a remarkable work-hardening like behavior and significant increase of plastic strain from less than 1%to 15%,and its plastic deformation dynamics yields a power-law distribution of shear *** upon the analysis of the experimental results,it is indicated that this can be connected to the SMAT-induced microstructural modifications and the resulting residual compressive stress in the Zr-based BMG.

关键词： Bulk metallic glass Surface mechanical attrition treatment Serrated flow Microstructure Residual stress

Analysis and design of Scheduling Schemes for Wireless Networks with Unsaturated Traffic

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China Communications 2021年第2期18卷 65-85页

作者： Jianfei li juan Wen Min Sheng State Key laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China

Scheduling schemes assign limited resources to appropriate users,which are critical for wireless network *** current schemes have been designed based on saturated traffic,i.e.,assuming users in networks always have data to ***,the user buffer may sometimes be empty in actual ***,these algorithms will allocate resources to users having no data to transmit,which results in resource *** view of this,we propose new scheduling schemes for onehop and two-hop link scenario with unsaturated ***,this paper analyzes their key network performance indicators,including the average queue length,average throughput,average delay and outage *** two scheduling algorithms avoid scheduling the links whose buffers are empty and thus improve the network resource *** the one-hop link scenario,network provides differentiated services via adjusting the scheduling probabilities of the destination nodes(dNs)with different *** the dNs with same priority,the node with higher data arrival rate has larger scheduling *** the two-hop link scenario,we prioritize the scheduling of relay-to-destination(R-d)link and dynamically adjust the transmission probability of source-to-relay(S-R)link,according to the length of remaining *** experiment results show the effectiveness and advantage of the proposed algorithms.

关键词： markov chain unsaturated traffic performance analysis scheduling

Asymmetric cell division in plant development

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Journal of Integrative Plant Biology 2023年第2期65卷 343-370页

作者： Yi Zhang Tongda Xu juan dong Plant Synthetic Biology Center Haixia Institute of Science and Technologyand College of Life SciencesFujian Agriculture and Forestry UniversityFuzhou 350002 China The Waksman Institute of Microbiology Rutgersthe State University of New JerseyPiscatawayNJ 08854USA department of Plant Biology Rutgersthe State University of New JerseyNew BrunswickNJ 08891USA

Asymmetric cell division(ACd) is a fundamental process that generates new cell types during development in eukaryotic *** plant development,post-embryonic organogenesis driven by ACd is universal and more important than in animals,in which organ pattern is preset during ***,plant development provides a powerful system to study molecular mechanisms underlying *** the past decade,tremendous progress has been made in our understanding of the key components and mechanisms involved in this important process in ***,we present an overview of how ACd is determined and regulated in multiple biological processes in plant development and compare their conservation and specificity among different model cell *** also summarize the molecular roles and mechanisms of the phytohormones in the regulation of plant ***,we conclude with the overarching paradigms and principles that govern plant ACd and consider how new technologies can be exploited to fill the knowledge gaps and make new advances in the field.

关键词： asymmetric cell division peptide signaling phytohormonal signaling polarity proteins plant development transcription factors

Cauchy matrix structure of the Mel’nikov model of long-short wave interaction

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Communications in Theoretical Physics 2020年第12期72卷 83-93页

作者： Hong-juan Tian da-Jun Zhang department of Mathematics Shanghai UniversityShanghai 200444China

We propose a systematic method to construct the Mel’nikov model of long–short wave interactions,which is a special case of the Kadomtsev–Petviashvili(KP)equation with self-consistent sources(KPSCS).We show details how the Cauchy matrix approach applies to Mel’nikov’s model which is derived as a complex reduction of the *** a new result wefind that in the dispersion relation of a 1-soliton there is an arbitrary time-dependent function that has previously not reported in the literature about the Mel’nikov *** function brings time variant velocity for the long wave and also governs the short-wave *** variety of interactions of waves resulting from the time-freedom in the dispersion relation is illustrated.

关键词： Mel’nikov model of long–short wave interaction Cauchy matrix approach self-consistent sources KP equation

Suitable conditions for natural regeneration in variable retention harvesting of southern Patagonian Nothofagus pumilio forests

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Ecological Processes 2019年第1期8卷 240-251页

作者： Mónica d.R.Toro Manríquez juan M.Cellini María V.lencinas Pablo l.Peri Karen A.Peña Rojas Guillermo J.Martínez Pastur Centro Austral de Investigaciones Científicas(CAdIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)Houssay 200(9410)UshuaiaTierra del FuegoArgentina laboratorio de Investigaciones en Maderas(lIMAd) Universidad Nacional de la Plata(UNLP)Diagonal 113 n°469(1904)La PlataBuenos AiresArgentina Instituto Nacional de Tecnología Agropecuaria(INTA) Universidad Nacional de la Patagonia Austral(UNPA)Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET)cc 332(9400)Río GallegosSanta CruzArgentina departamento de Silvicultura y Conservación de la Naturaleza Facultad de Ciencias Forestales y de Conservación de la NaturalezaUniversidad de Chilecc 9206SantiagoChile.

Background:Variable retention(aggregated and dispersed retention)harvesting proposed for Nothofagus pumilio was designed for timber purposes and biodiversity *** by opening canopy generates different microenvironments and creates contrasting conditions for seedling establishment,growth,and eco-physiology performance due to synergies(positives or negatives)with biotic and abiotic *** study evaluated the regeneration in different microenvironment conditions within managed stands during 5 years after *** forest structure after harvesting and different microenvironments were characterized in managed stands,where 105 regeneration plots were measured(3 stands×7 microenvironments×5 replicas).We characterized the seedling bank,as well as growth and ecophysiology performance of the *** and multivariate analyses were conducted for the ***:Microenvironments offered different environmental conditions for natural regeneration(soil moisture and light availability).Seedling under debris and dicot plants showed better eco-physiological performance,establishment,and growth than plants growing under monocots or located in the dispersed retention without the protection of other understory *** most unfavorable microenvironment conditions were high canopy cover of remnant trees(inside the aggregates or close to trees in the dispersed retention)and heavily impacted areas(skidder extraction roads).Conclusions:Favorable microenvironments in the harvested areas will improve the natural recruitment,growth,and eco-physiology performance of the natural regeneration after *** is necessary to develop new silvicultural practices that decrease the unfavorable microenvironments(e.g.,road density or excessive woody accumulation),to assure the success of the proposed silvicultural method.

关键词： Aggregated retention dispersed retention Microenvironments Environmental variables Biometric values Biomass allocation Eco-physiology

decomposition characteristics of organic materials and their effects on labile and recalcitrant organic carbon fractions in a semi-arid soil under plastic mulch and drip irrigation

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Journal of Arid land 2018年第1期10卷 115-128页

作者： hu juan wu jinggui qu xiaojing college of resource and environmental science jilin agricultural universityChangchun 130118China

labile organic carbon （lC） and recalcitrant organic carbon （RC） are two major fractions of soil organic carbon （SOC） and play a critical role in organic carbon turnover and sequestration. The aims of this study were to evaluate the variations of lC and RC in a semi-arid soil （Inner Mongolia, China） under plastic mulch and drip irrigation after the application of organic materials （OMs）, and to explore the effects of OMs from various sources on lC and RC by probing the decomposition characteristics of OMs using in-situ nylon mesh bags burying method. The field experiment included seven treatments, i.e., chicken manure （CM）, sheep manure （SM）, mushroom residue （MR）, maize straw （MS）, fodder grass （FG）, tree leaves （Tl） and no OMs as a control （CK）. Soil lC and RC were separated by Huygens d＇s method （particle size-density）, and the average soil mass recovery rate and carbon recovery rate were above 95%, which indicated this method was suitable for carbon pools size analysis. The lC and RC contents significantly （P〈0.01） increased after the application of OMs. Moreover, lC and RC contents were 3.2%-8.6% and 5.0%-9.4% higher in 2016 than in 2015. The applications of CM and SM significantly increased （P〈0,01） lC content and lC/SOC ratio, whereas they were the lowest after the application of Tl. However, SOC and RC contents were significantly higher （P〈0.01） after the applications of Tl and MS. The correlation analysis indicated the decomposition rate of OMs was positively related with lC content and lC/SOC ratio. In addition, lignin, polyphenol, WOM （total water-soluble organic matter）, WHA （water-soluble humic acid）, HSl （humicdike substance） and HAl （humic acid-like） contents in initial OMs played important roles in SOC and RC. In-situ nylon mesh bags burying experiment indicated the decomposition rates of CM, SM and MS were significantly higher than those of MR, FG, and Tl. Furthermore, MS could result in more lignin derivatives, WHA, and HAl polymers in shorter time

关键词： organic materials labile organic carbon recalcitrant organic carbon decomposition characteristics plasticmulch drip irrigation Inner Mongolia

Physiological strategies of moult-migrating Black-necked Grebes(Podiceps nigricollis)in a polluted staging site according to blood chemistry

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Avian Research 2023年第3期14卷 453-459页

作者： juan A.Amat Nico Varo Marta I.Sanchez Andy J.Green damaso Hornero-Mendez juan Garrido-Fernandez Cristina Ramo departamento de Ecología y Evolucion Estacion Biologica de Donana(EBD-CSIC)41092SevillaSpain Independent researcher 41010SevillaSpain departamento de Biología de la Conservacion y Cambio Global Estacion Biologica de Donana(EBD-CSIC)41092SevillaSpain departamento de Fitoquímica de Alimentos Instituto de la Grasa(IG-CSIC)41013SevillaSpain

After breeding,Black-necked Grebes(Podiceps nigricollis)perform a moult-migration to autumn hypersaline staging sites,where they moult the flight feathers and forage on superabundant brine shrimp(Artemia spp.)before leaving for wintering *** the stay in moulting sites,the grebes experience changes in organs and muscle size(atrophy,hypertrophy),and almost double their body mass,which has been suggested to act as an insurance against a collapse in prey availability in late *** two years we collected blood samples from hundreds of individuals at one of the most important European moulting sites(the Odiel marshes,SW Spain),which is a highly polluted area due to mining drainage and chemical *** assessed the potential effect of moulting stage,day of the year and body condition on 16 blood biochemical *** of the changes in prey availability and body composition of grebes,we expected some physiological adjustments during *** levels of cholesterol suggested that birds in active moult increased foraging effort to face the costs of *** was increased amount of lactate dehydrogenase,corresponding to periods of breast muscle *** in active moult augmented protein ingestion,likely to account for the requirements of feather *** also show that the probability of fasting due to low prey availability increased late in the moulting season,as demonstrated by an increase in plasmaβ-hydroxy-butyrate.

关键词： Blood biochemistry Eared grebe Fasting Feather replacement Odiel marshes Waterbird

Gene Expression Patterns in different Wool densities of Rex Rabbit Using cdNA Microarray

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Agricultural Sciences in China 2011年第4期10卷 595-601页

作者： CHEN Sai-juan lIU Tao lIU Ya-juan dONG Bing GU Zi-lin College of Animal Science and Technology Agricultural University ofHebei Baoding 071001 P.R. China Ringpu （Baoding） Biological Pharmaceutical Co. Ltd. Baoding 071000 P.R. China Mountain Area Research Institute Agricultural University of Hebei Baoding 071001 P.R.China division of Scientific Research Agricultural University of Hebei Baoding 071001 P.R.China

This study was carried out to identify gene expression patterns in different wool densities of rex rabbit. The mid-dorsal skin samples from 8 rex rabbits were studied. They were divided into two groups according to different wool densities. Total RNA was isolated and labeled by reverse transcription reaction with Cy5-dCTP and Cy3-dCTP for cdNA probe. The cdNA probe was hybridized with cdNA microarrays containing 14 601 rabbit’s genes. The differently expressed genes were analysed with the Gene Ontology （GO） classification and the pathway analysis. Hierarchical clustering was performed to clarify genes in association with different wool densities. The 2 657 differentially expressed genes were identified. Among them, 1 103 genes were functionally known genes, 687 genes were up-regulated and 419 were down-regulated. GO analysis indicated that these altered genes were associated with metabolism, signal transduction, cell cycle, cell adhesion, cell proliferation, cell division, apoptosis, and other processes. KEGG analysis showed that 95 signal pathways associated with up-regulated genes and 87 signal pathways associated with down-regulated genes had changed significantly （P0.05）. Some important differentially expressed genes in different wool densities of rex rabbit were identified, such as MMP2, TGF-β1, TGF-β2, IGF-1, ITGB1, RPS6KB1, BMP2, ActRIIB, CdK2, and CCNA2. Hierarchical clustering analysis separated the differentially expressed genes into 5 main characteristic groups. data from cdNA microarray experiments clearly distinguished between group A and group B. Some important genes were identified, which might be useful in further study on wool density markers of rex rabbit.

关键词： rex rabbit wool density gene expression cdNA microarray GO and KEGG analysis

leaf Gas Exchange,Chlorophyll Fluorescence,and Fruit Yield in Hot Pepper (Capsicum anmuum l.) Grown Under different Shade and Soil Moisture during the Fruit Growth Stage

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Journal of Integrative Agriculture 2012年第6期11卷 927-937页

作者： ZHU juan-juan PENG Qiang lIANG Yin-li WU King HAO Wang-lin College of life Sciences Northwest A&F University Yangling 712100 P.R.China Extension Center of Agricultural Technology Fengxian Agricultural Bureau Fengxian 721700 P.R.China Institute of Soil and Water Conservation the Chinese Academy of Sciences/Ministry of Water Resources Yangling 712100 P..R.China

Relative leaf chlorophyll （Chl.） content, leaf gas exchange, Chl. fluorescence, plant biological biomass, and fruit yield were evaluated in growing hot pepper （Capsicum annuum l.） during the fruit-growing stages in hot summer under three shade levels （un-shade, 30% shade, and 70% shade） and four soil water contents （SWC） of 40-55%, 55-70%, 70-85%, and 85- 100% of field moisture capacity （FMC）. Hot pepper crops were more affected by light irradiance than by soil moisture and by their interaction during the whole observed periods. Hot pepper attained greatest relative leaf Chl. content （expressed as SPAd value） and photosynthetic activity when cultivated with 30% shade, resulting in the highest plant biological biomass and fruit yield. Although 70% shade improved leaf photosynthetic efficiency （expressed as Fv/Fm or Fv＇/Fm＇）, crops obtained the lowest photosynthetic rate, photochemical quenching coefficient （qP）, and non-photochemical quenching coefficient （NPQ）. This showed that light irradiance was insufficiency in S70% （70% shade） treatment. The leaf net photosynthetic rates （PN）, Fc/Fm, and fruit yield increased gradually as SWC levels increased from 40-55% to 70- 85% FMC, but decreased as SWC was higher than 70-85% FMC. The water consumption increased progressively with SWC levels, but water-use efficiency （WUE） was the highest when soil moisture was 55-70% FMC. Interaction of shade and soil moisture had significant effects on PN and FJFm, but not on other parameters. Under drought stress （40-55% and 55-70% FMC）, 30% shade could relieve the droughty damage of crops and improve photosynthetic capacity and WUE, but 70% shade could not, oppositely, aggravate the damage. The positive correlation （r2 =0.72） between leaf PN and fruit yield was existent. This indicated that improvement of leaf photosynthesis would increase potentially marketable yield in hot pepper crops during the full fruit-growing stages. For agricultural purposes, approximately S30% （30% shade） with

关键词： leaf chlorophyll content photosynthetic capacity interaction

Experimental Study on the Uniaxial Cyclic deformation of 25CdV4.11 Steel

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Journal of Materials Science & Technology 2005年第1期21卷 5-9页

作者： Guozheng KANG, Qianhua KAN and juan ZHANGdepartment of Applied Mechanics and Engineering, Southwest Jiaotong University, Chengdu 610031, ChinaProf., Ph.d., dept. of Appl. Mech. and Eng. Southwest Jiaotong Univ. Chengdu 610031 China

The strain cyclic characteristics and ratcheting behavior of 25CdV4.11 steel were studied by the experiments under uniaxial cyclic loading with relatively high cyclic number and at room temperature. The cyclic hardening/softening feature of the material was first observed under the uniaxial strain cycling with various strain amplitudes. Then, the ratcheting behavior of the material was researched in detail, and the effects of stress amplitude and mean stress on the ratcheting were discussed under uniaxial asymmetrical stress cycling. Comparing with the experimental results of SS316l stainless steel, it is concluded that the material exhibits remarkable cyclic softening feature, and then a special ratcheting behavior is caused. Some conclusions useful to establish corresponding constitutive model are obtained.

关键词： Ratcheting Cyclic softening Cyclic plasticity Uniaxial loading