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SIMULATIONS OF THE THREE-DIMENSIONAL TOTAL DISSOLVED GAS SATURATION DOWNSTREAM OF SPILLWAYS UNDER UNSTEADY CONDITIONS

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Journal of Hydrodynamics 2010年第4期22卷 598-604页

作者： FU xiao-li LI dan zhang xiao-feng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

Dams are often operated in a way to discharge over the spillways,which would cause a high dissolved concentration of air and be harmful to *** bubble transfer and the water surface transfer play an important role in affecting the concentration of the Total Dissolved Gas（TDG）.Based on recent numerical simulations of the total dissolved gas saturation,in this article,a two-phase TDG transport equation is adopted to develop an unsteady three-dimensional（3-D） two-phase flow Computational Fluid Dynamics（CFD） model,including a number of parameters such as water depth,pressure and air volume *** model is used to predict the hydrodynamics and the TDG distribution under unsteady discharge *** agreement between measured and numerical results is obtained for a case study.

关键词： gas supersaturation anisotropic two-phase flow

Optimization of axial symmetrical FGM under the transient-state temperate field

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International Journal of Minerals,Metallurgy and Materials 2012年第1期19卷 59-63页

作者： xiao-dan zhang Ya-li Hong Ai-hua Li School of Mathematics and Physics University of Science and Technology Beijing Beijing 100083 China Department of Mathematical Science Montclair State University New Jersey 07043 USA

A numerical procedure for analyzing the temperature distribution in a hollow axisymmetric cylinder, made of functionally gradient material （FGM）, was investigated. Based on the thermal elasticity theory and the arbitrary difference precise integration （ADPI） method, temperature distribution through the FGM cylinder in the ring section under a transient-state temperature field was developed and presented. A genetic algorithm （GA） was applied to the thermal stress optimal design of an FGM hollow cylinder, and as a result, the minimum thermal stress distribution in the FGM cylinder was obtained. A corresponding numerical procedure regarding to a ceramic-metal FGM cylinder was perforrned. and the comnutational results were discussed.

关键词： functionally gradient materials axial symmetry tempemtttre distribution genetic algorithms numerical methods

Parental dependence on the nest's spatial cues in offspring recognition decreases with nestling growth in the azure-winged magpie

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Current Zoology 2020年第6期66卷 643-648页

作者： Li-Fang Gao Wen zhang Hai-Yang zhang Zhen-Qin Zhu xiao-dan zhang Bo Du School of Life Sciences Lanzhou UniversityLanzhou730000China

In altricial birds,to address which cues are used by parents to recognize their offspring,and when they switch between cues during reproduction,it has not been well *** this study,we address this questi on in a Tibetan populatio n of the azure-winged magpie Cyanopica cyan us f by examining the dependence of parents on a nest's spatial position in offspring *** the egg and nestling phases,azure-winged magpie nests were translocated to new positions across various distances from their original site,and parental responses to the translocated nests were *** findings show that a nesfs spatial position is not connected with the survival of its young,but might be used as a cue in parental offspring *** nests are translocated to a new position within a certain distance,parents could recognize their nests and returned to resume their parenting *** dependence on the nest's spatial position in offspring recognition is higher during the egg phase than during the nestling phase,and it decreases with the growth of *** nestlings reach a certain age,the nest's spatial position was no longer used by pare nts as the single cue for offspring recog *** findings suggest that azure-winged magpies switch their cues in offspring recog nition during the differe nt stages of *** parent-offspring communication has been established,the offspring's phenotypic traits may become a more reliable cue than the nests spatial position in offspring recognition.

关键词： homing nest spatial position nest translocation experiment offspring recognition

Fitness consequences of divorce in the azure-winged magpie depends on the breeding experience of a new mate

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Current Zoology 2021年第1期67卷 17-25页

作者： Li-Fang GAO Hai-Yang zhang Wen zhang xiao-dan zhang Zhen-Qin ZHu Bo Du School of Life Sciences Lanzhou UniversityTianshui South Road 222#Lanzhou CityGansu Province730000China

Sexual conflict in producing and raising offspring is a critical issue in evolutionary ecology *** experience affects their breeding performance,as measured by such traits of provisioning of offspring and engagement in extra-pair copulations,and may cause an imbalance in sexual ***,divorce is hypothesized to occur within aged social pairs,irrespective of current reproductive *** concept was explored in the azure-winged magpie Cyanopica cyanus by investigating the divorce of a social pair and its relationship to their changes in breeding performance with prior *** engaging in extra-pair copulation may intensify sexual conflicts and may be the main reason for *** divorced,females repairing with an inexperienced male realized higher reproductive success than that repairing with an experienced male;males repairing with an experienced female realized higher reproductive success than that repairing with an inexperienced *** finding indicates that the fitness consequence of divorce depends on the breeding experience of new *** females can obtain more extra-pair copulations,whereas divorced males cannot,when they repair with inexperienced *** females provisioned a brood at lower rates than inexperienced females whereas divorced males had no such *** appears that divorced females can obtain an advantage in sexual conflicts with inexperienced mates in future ***,females are probably more active than males in divorcing their aged mates so as to select an inexperienced male as a new ***-winged magpies thus provide novel insights into the implicaticns of sexual conflict in birds.

关键词： breeding experience extra-pair copulation parental care provisioning rate sexual conflict

High Ductility and Toughness of a Micro-duplex Medium-Mn Steel in a Large Temperature Range from—196 ℃ to 200 ℃

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Journal of Iron and Steel Research International 2015年第12期22卷 1126-1130页

作者： Si-lian CHEN Jun HU xiao-dan zhang Han DONG Wen-quan CAO Central Iron and Steel Research Institute School of Materials Science and Engineering Huazhong University of Science and Technology danish-Chinese Centre for Nanometals Section for Materials Science and Advanced CharacterizationDepartment of Wind EnergyTechnical University of Denmark

A medium-Mn steel （0.2C5Mn） was processed by intercritical annealing at different temperatures （625 ℃ and 650 ℃ ）. An ultrafine-grained micro-duplex structure consisting of alternating austenite and ferrite laths was de- veloped by austenite reverse transformation （ART） during intercritical annealing after forging and hot rolling. Ultra- high ductility with a total elongation higher than 30% was achieved in the temperature range from -196 ℃ to 200 ℃, and high impact toughness no less than 200 J at -40 ℃ was obtained. Based on the analysis of microstructure and mechanical properties, it was found that the enhanced ductility was determined by the phase transformation effect of austenite （TRIP effect）, while the delayed ductile to brittle transition was controlled by austenite stability.

关键词： high strength high ductility intercritical annealing medium-Mn steel ultrafine grain size

Odorant receptor orthologues from moths display conserved responses to cis-jasmone

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Insect Science 2024年第4期31卷 1107-1120页

作者： xiao-Qing Hou Zhongqiang Jia dan-dan zhang Guirong Wang Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureSynthetic Biology Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong ProvinceChina State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina Department of Biology Lund UniversityLundSweden

In insects,the odorant receptor(OR)multigene family evolves by the birth-and-death evolutionary model,according to which the OR repertoire of each species has undergone specific gene gains and losses depending on their chemical environment,resulting in taxon-specific OR lineage radiations with different sizes in the phylogenetic *** the general divergence in the gene family across different insect orders,the ORs in moths seem to be genetically conserved across species,clustered into 23 major clades containing multiple orthologous groups with single-copy gene from each *** hypothesized that ORs in these orthologous groups are tuned to ecologically important compounds and functionally ***-Jasmone is one of the compounds that not only primes the plant defense of neighboring receiver plants,but also functions as a behavior regulator to various *** test our hypothesis,using Xenopus oocyte recordings,we functionally assayed the orthologues of BmorOR56,which has been characterized as a specific receptor for *** results showed highly conserved response specificity of the BmorOR56 orthologues,with all receptors within this group exclusively responding to *** is supported by the dN/dS analysis,showing that strong purifying selection is acting on this ***,molecular docking showed that the ligand binding pockets of BmorOR56 orthologues to cis-jasmone are *** together,our results suggest the high conservation of OR for ecologically important compounds across Heterocera.

关键词： cis-jasmone evolutionary conservation functional characterization molec-ular docking moths purifying selection

Total ionizing dose effect modeling method for CMOS digital-integrated circuit

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Nuclear Science and Techniques 2024年第2期35卷 32-46页

作者： Bo Liang Jin-Hui Liu xiao-Peng zhang Gang Liu Wen-dan Tan Xin-dan zhang School of Computer Science and Technology Xidian UniversityXi’an 710071China

Simulating the total ionizing dose(TID)of an electrical system using transistor-level models can be difficult and expensive,particularly for digital-integrated circuits(ICs).In this study,a method for modeling TID effects in complementary metaloxide semiconductor(CMOS)digital ICs based on the input/output buffer information specification(IBIS)was *** digital IC was first divided into three parts based on its internal structure:the input buffer,output buffer,and functional *** of these three parts was separately *** the IBIS model,the transistor V-I characteristic curves of the buffers were processed,and the physical parameters were extracted and modeled using *** the functional area,logic functions were modeled in VHDL according to the data sheet.A golden digital IC model was developed by combining the input buffer,output buffer,and functional area ***,the golden ratio was reconstructed based on TID experimental data,enabling the assessment of TID effects on the threshold voltage,carrier mobility,and time series of the digital *** experiments were conducted using a CMOS non-inverting multiplexer,NC7SZ157,and the results were compared with the simulation results,which showed that the relative errors were less than 2%at each dose *** confirms the practicality and accuracy of the proposed modeling *** TID effect model for digital ICs developed using this modeling technique includes both the logical function of the IC and changes in electrical properties and functional degradation impacted by TID,which has potential applications in the design of radiation-hardening tolerance in digital ICs.

关键词： CMOS digital-integrated circuit Total ionizing dose IBIS model Behavior-physical hybrid model Physical parameters

Fecal consumption by adults of altricial birds in relation to the temporal change in nestling gut microbiota

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Current Zoology 2020年第6期66卷 689-691页

作者： Li-Fang Gao Wen zhang Hai-Yang zhang Zhen-Qin Zhu xiao-dan zhang Jian-Chuan Li Li-Qing Fan Bo Du School of Life Sciences Lanzhou UniversityLanzhou 730000China Tibet Plateau Institute of Biology Lhasa 850000China Institute of Plateau Ecology Xizang Agriculture and Animal Husbandry CollegeLinzhi CityTibet 860000China

Nest sanitation behavior of altricial birds has been selected to reduce the exposure of young to pathogens,parasites,or predators,and thus to maintain the health and safety of nestlings(Guigueno and Sealy 2012).During the process of nest sanitation,caregivers either carry away the fecal sacs of nestlings or directly eat *** that adults endure higher risk of being infected by pathogens during fecal consumption(Potti et al.2007),it remains a puzzle about why adults consume the nestling feces when they can transport *** hypotheses have been proposed to explain the fecal consumption behavior of altricial birds,including the nutrition hypothesis(Gliick 1988),economic hypothesis(Hurd et al.1991),and predation hypothesis(Ibanez-Alamo et al.2013).

关键词： fecal consumption giant babax gut microbiota

A diagnosis model of parental care:How parents optimize their provisioning strategy in brood reduction?

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Current Zoology 2023年第4期69卷 385-392页

作者： Zhen-Qin Zhu Shu-Mei Zi Li-Fang Gao xiao-dan zhang Fang-Yuan Liu Qian Wang Bo Du School of Life Sciences Lanzhou UniversityLanzhou CityGansu Province 730000China College of Ecology Lanzhou UniversityLanzhou CityGansu Province 730000China

Altricial birds often display biased preferences in providing parental care for their dependent offspring,especially during food *** this process,such inflexible rules may result in provisioning *** demonstrate how parents optimize their provisioning strategies,we proposed a“diagnosis model”of parental care to posit that parents will undergo a diagnosis procedure to test whether selecting against some particular offspring based on phenotype is an optimal *** tested this model in an asynchronous hatching bird,the Azure-winged Magpie Cyanopica cyanus,based on 10 years of data about demography and parental provisioning *** their higher daily survival rates,core offspring(those hatched on the first day)merits an investment priority compared with their marginal brood mates(those hatched on later days).However,a marginal offspring also merited a priority if it displayed greater weight gain than the expected value at the early post-hatching *** could detect such a marginal offspring via a diagnosis strategy,in which they provisioned the brood at the diagnosis stage by delivering food to every nestling that begged,then biased food toward high-value nestlings at the subsequent decision stage by making a negative response to the begging of low-value *** this provisioning strategy,the growth performance of a nestling became a more reliable indicator of its investment value than its hatching order or competitive *** findings provide evidence for this“diagnosis model of parental care”wherein parents use a diagnosis method to optimize their provisioning strategy in brood reduction.

关键词： brood reduction parental care provisioning strategy weight gain