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Cellular automata simulation of grain growth of powder metallurgy Ni-based superalloy

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Journal of Iron and Steel Research International 2023年第4期30卷 838-848页

作者： Yi-ling Jiang Sha-sha liu rong-gui Lu Xu Cheng Jia Li Yang Chen Gao-feng Tian School of Materials Science and Engineering Beihang UniversityBeijing 100191China National Engineering Laboratory of Additive Manufacturing for Large Metallic Components Beijing 100191China Beijing Institute of Aeronautical Materials Beijing 100095China

Primary γ'phase instead of carbides and borides plays an important role in suppressing grain growth during solution at 1433 K of Ni-based FGH98 *** illustrate that as-fabricated FGH98 superalloy has equiaxed grain structure,and after heat treatment,grains remain equiaxed but grow *** order to clarify the effects of the size and volume fraction of the primaryγ'phase on the grain growth during heat treatment,a 2D cellular automata(CA)model was established based on the thermal activation and the lowest energy *** CA results are compared with the experimental results and show a good fit with an error less than 10%.Grain growth kinetics are depicted,and simulations in real time for various sizes and volume fractions of primaryγ'particles work out well with the Zener *** coefficient n value which reflects the pinning ability in Zener relation is theoretically calculated,and its minimum value is 0.23 when the radius of primaryγ'phase is 2.8μm.

关键词： Grain growth Cellular automata Ni-based FGH98 superalloy Primary γ'phase Microstructure

Ligand-binding properties of three odorant-binding proteins of the diamondback moth Plutella xylostella

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Journal of Integrative Agriculture 2016年第3期15卷 580-590页

作者： ZHU Jiao Paolo Pelosi liu Yang LIN Ke-jian YUAN Hai-bin WANG gui-rong College of Agriculture Jilin Agricutural University State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences

Strategies for insect population control are currently targeting chemical communication at the molecular level. The diamondback moth Plutella xylostella represents one of the most serious pests in agriculture, however detailed information on the proteins mediating olfaction in this species is still poor. This species is endowed with a repertoire of a large number of olfactory receptors and odorant binding proteins（OBPs）. As a contribution to map the specificities of these chemical sensors in the moth and eventually unrave l the complexity of chemodetection, we have measured the affinities of three selected OBPs to a series of potential odorants. Three proteins are highly divergent in their amino acid sequences and show markedly different expression profiles. In fact, PxylOBP3 is exclusively expressed in the antennae of both sexes, PxylOBP9 is male specific and present only in antennae and reproductive organs, while PxylOBP19, an unusual OBP with nine cysteines, is ubiquitously present in all the organs examined. Such expression pattern suggests that the last two proteins may be involved in non-chemosensory functions. Despite such differences, the three OBPs exhibit similar binding spectra, together with high selectivity. Among the 26 natural compounds tested, only two proved to be good ligands, retinol and coniferyl aldehyde. This second compound is particularly interesting being part of the chemical pathway leading to regeneration of lignin, one of the defense strategies of the plant against insect attack, and might find applications as a repellent for P. xylostella and other pests.

关键词： odorant-binding protein Plutella xylostella ligand-binding tryptophan quenchin molecular docking

Three dimensional phase-field simulation for non-isothermal binary alloy solidification: Comparison with LKT theory

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China Foundry 2023年第6期20卷 545-552页

作者： Jun Wu Ting-yi liu gui-chao Hu rong Ma Xiao-peng Zhang Yu-fei Li Chao Luo Institute of Materials China Academy of Engineering PhysicsJiangyou 621907SichuanChina

Using the advanced algorithm combining parallel computing,adaptive mesh re-griding and multigrid methods,quantitative 3D phase-field simulations of non-isothermal solidification of binary alloy were carried *** 3D phase-field simulation results were compared with the analytical LKT(Lipton,Kurz and Trivedi)*** comparison,the simulation and analytical results for 2D cases were also *** 3D phase-field simulation results support the transport portion of the LKT ***,the tip radius and tip velocity predicted by the simulations are not in good agreement with the LKT theory over the whole range of *** stability parameter calculated from phase-field simulations varies significantly with the Peclet number,indicating that the stability criterion,which assumes that the stability parameter is constant,is invalid.

关键词： 3D phase-field non-isothermal solidification free dendritic growth

Numerical Investigation of Three-dimensional Aeroacoustic Characteristics of Owl-inspired Trailing-edge Fringes

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Journal of Bionic Engineering 2023年第3期20卷 1103-1120页

作者： Jiaxin rong Hao liu Shanghai Jiao Tong University and Chiba University International Cooperative Research Center(SJTU-CU ICRC) Shanghai200240China Graduate School of Engineering Chiba University1-33Yayoi-choInage-kuChiba263-8522Japan

Owls are widely known for their silent flight,which is attributed to their unique wing morphologies comprising leading-edge(LE)serrations,trailing-edge(TE)fringes,and a velvety *** aeroacoustic characteristics of owl-inspired TE fringes have been widely investigated through two-dimensional(2D)modeling,but remain yet poorly studied in association with their three-dimensional(3D)***,we present a numerical study of the 3D aeroacoustic characteristics of owl-inspired TE fringes in which we combined large-eddy simulations(LES)with the Ffowcs Williams‒Hawkings *** constructed a clean wing model and three wing models with TE fringes that were distributed differently *** aerodynamic forces and 3D acoustic characteristics reveal that,like the 2D results of our previous studies,the 3D TE fringes enable remarkable sound reduction spatially while having aerodynamic performance comparable to the clean *** of the near-field 3D flow structures,vortex dynamics,and flow fluctuations show that TE fringes can robustly alter the 3D flow by breaking 3D TE vortices into small eddies and mitigating 3D flow ***,it is verified that TE fringes alter spanwise flows,thus dominating the 3D aeroacoustic characteristics in terms of passive flow control and flow stabilizations,whereas the fringes are inefficient in suppressing the acoustic sources induced by wingtip ***,the TE fringes distributed at midspan have better acoustic performance than those in the vicinity of the wingtip,indicating the importance of a spanwise distribution in enhancing aeroacoustic performance.

关键词： Owl Three-dimensional trailing-edge fringes Aeroacoustics Large-eddy simulation Ffowcs Williams‒Hawkings equation

New Upper Bounds on Linear Coloring of Planar Graphs

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Acta Mathematica Sinica,English Series 2012年第6期28卷 1187-1196页

作者： Bin liu gui Zhen liu Department of Mathematics Ocean University of China School of Mathematics Shandong University

A proper vertex coloring of a graph G is linear if the graph induced by the vertices of any two color classes is the union of vertex-disjoint paths. The linear chromatic number lc（G） of the graph G is the smallest number of colors in a linear coloring of G. In this paper, it is proved that every planar graph G with girth g and maximum degree A has （1） lc（G） ≤ △ ＋ 21 if △ ≥ 9; （2） lc（G） ≤[△/2]＋ 7 if g≥5; （3） lc（G） ≤ [△/2]＋2ifg≥7and△ ≥7.

关键词： Linear coloring planar graph girth

Complementary fruiting phenologies facilitate sharing of one pollinator fig wasp by two fig trees

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Journal of Plant Ecology 2015年第2期8卷 197-206页

作者： gui-Xiang liu Da-rong Yang Yan-Qiong Peng Stephen G.Compton Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences88 Xuefu RoadKunming 650223China University of Chinese Academy of Science 19 Yuquan roadBeijing 100049China School of Biology University of LeedsWoodhouse LaneLeeds LS29JTUK Department of Zoology and Entomology Rhodes UniversityLower University RoadGrahamstown 6140South Africa

Aims most pollinator fig wasps are host plant specific,with each spe-cies only breeding in the figs of one fig tree species,but increasing numbers of species are known to be pollinated by more than one fig wasp,and in rare instances host switching can result in Ficus species sharing *** this study,we examined factors facilitating observed host switching at Xishuangbanna in southwestern(sW)China,where Ficus squamosa is at the northern edge of its range and lacks the fig wasps that pollinate it elsewhere,and its figs are colonized by a Ceratosolen pollinator that routinely breeds in figs of *** We recorded the habitat preferences of *** and ***-yla at Xishuangbanna,and compared characteristics such as fig size,location and colour at receptive ***,the vegetative and reproductive phenologies in the populations of *** and *** were recorded weekly at Xishuangbanna Tropical botanical garden for 1 *** Findings Ficus squamosa is a shrub found near fast-flowing rivers,*** is a small tree of disturbed forest *** preferring different habitats,they can be found growing close *** species have figs located at or near ground level,but they differ in size when *** production in *** was concentrated in the colder *** produced more figs in summer but had some through-out the *** absence of its normal pollinators,in combination with similarly located figs and partially complementary fruiting patterns appear to have facilitated colonization of *** by the routine pollinator of *** figs probably also share similar attractant *** host switching suggests one mechanism whereby fig trees can acquire new pollinators and emphasizes the likely significance of edges of ranges in the genesis of novel fig tree-fig wasp relationships.

关键词： agaonidae edge of range Ficus host specificity host switching

A Uniqueness Theorem of a System of Nonlinear Equations and Its Applications

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 111-120页

作者： rong liu College of Computer and Information Science Fujian Agriculture and Forestry University College of Mathematics and Computer Science Hunan Normal University

A uniqueness theorem of a solution of a system of nonlinear equations is given. Using this result uniqueness theorems for power orthogonal polynomials, for a Gaussian quadrature formula of an extended Chebyshev system... 详细信息

关键词： uniqueness theorems power orthogonal polynomials Gaussian quadrature formula extendedChebyshev system Gaussian Birkhoff quadrature formula

Functional characterization of pheromone receptor candidates in codling moth Cydia pomonella(Lepidoptera:Tortricidae)

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Insect Science 2021年第2期28卷 445-456页

作者： Ke Tian Wei liu Li-Kai Feng Tian-Yu Huang gui-rong Wang Ke-Jian Lin State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijingChina Institute of Plant Protection Xinjiang Academy of Agricultural and Reclamation ScienceShiheziXinjiang Uygur Autonomous RegionChina Lingnan Guangdong Laboratory of Modern Agriculture Genome Analysis Laboratory of the Ministry of AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhenGuangdong ProvinceChina

Sex pheromones serve a critical role in Lepidopterans finding *** moths perceive and react to sex pheromones emitted by conspecific females through a delicate pheromone communication *** receptors(PRs)are the key sensory elements at the beginning of that *** codling moth(Cydia ponwonella)is an important pome fruit pest globally and a serious invasive species in *** techniques have been used successfully in monitoring and controlling this *** conducted ribonucleic acid sequencing analysis of the codling moth antennal transcriptome and identified 66 odorant receptors(ORs)in a population from Xinjiang province,China,of which 14 were PRs,including two novel PRs(CpomOR2e and CpomOR73).Four PRs that contain full-length open reading frames(CpomORl,OR2a,OR5,OR7)and four PRs with ligands that have not been reported previously(CpomORl,OR2a,OR5,OR7)were selected to deorphanize in the heterologous Xenopus oocyte expression ***,we found that CpomOR2a and CpomOR5 responded to(£,£)-8,10-dodecadien-l-yl acetate(codlemone acetate).Furthermore,CpomOR5(EC50=1.379 x 10-8 mol/L)was much more sensitive to codlemone acetate than CpomOR2a(EC50=1.663×10^(-6) mol/L).Since codlemone acetate is an important component of *** sex pheromone,our results improve the current understanding of pheromone communication in codling moths and will be helpful for the development of pest management strategies.

关键词： antennal transcriptome codlemone acetate Cydia pomonella',pheromone receptor

The effects of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents:a meta-analysis

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Neural Regeneration Research 2025年第5期20卷 1513-1520页

作者： Xueyun Shao Longfei He Yangyang liu Physical Education School Shenzhen UniversityShenzhenGuangdong ProvinceChina Shenzhen Institute of Neuroscience ShenzhenGuangdong ProvinceChina

Brain-derived neurotrophic factor is a crucial neurotrophic factor that plays a significant role in brain health. Although the vast majority of meta-analyses have confirmed that exercise interventions can increase brain-derived neurotrophic factor levels in children and adolescents, the effects of specific types of exercise on brain-derived neurotrophic factor levels are still controversial. To address this issue, we used meta-analytic methods to quantitatively evaluate, analyze, and integrate relevant studies. Our goals were to formulate general conclusions regarding the use of exercise interventions, explore the physiological mechanisms by which exercise improves brain health and cognitive ability in children and adolescents, and provide a reliable foundation for follow-up research. We used the Pub Med, Web of Science, Science Direct, Springer, Wiley Online Library, Weipu, Wanfang, and China National Knowledge Infrastructure databases to search for randomized controlled trials examining the influences of exercise interventions on brain-derived neurotrophic factor levels in children and adolescents. The extracted data were analyzed using Review Manager 5.3. According to the inclusion criteria, we assessed randomized controlled trials in which the samples were mainly children and adolescents, and the outcome indicators were measured before and after the intervention. We excluded animal experiments, studies that lacked a control group, and those that did not report quantitative results. The mean difference(MD;before versus after intervention) was used to evaluate the effect of exercise on brain-derived neurotrophic factor levels in children and adolescents. Overall, 531 participants(60 children and 471 adolescents, 10.9–16.1 years) were included from 13 randomized controlled trials. Heterogeneity was evaluated using the Q statistic and I^(2) test provided by Review Manager software. The meta-analysis showed that there was no heterogeneity among the studies(P = 0.67,

关键词： adolescents brain-derived neurotrophic factor children exercise meta-analysis randomized controlled trials