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Competitive interactions a.d.coexistence of sympatric flagship carnivores in Asia

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Integrative Zoology 2024年第2期19卷 183-199页

作者： Zhilin li Jiayu LU Xiaoyi SHI li’an dUO James L.d.SMITH Tianming WANG Tianjin Key Laboratory of Conservation a.d.Utilization of Animal diversity College of Life SciencesTianjin Normal UniversityTianjinChina department of Fisheries Wildlife and Conservation BiologyUniversity of MinnesotaSt.PaulMinnesotaUSA Ministry of Education Key Laboratory for Biodiversity Science a.d.Engineering College of Life SciencesBeijing Normal UniversityBeijingChina National Forestry a.d.Grassla.d.Administration Key Laboratory for Conservation Ecology of Northeast Tiger a.d.Leopard BeijingChina

Understa.d.ng the competition a.d.coexistence of flagship carnivores is key to creating strategies for their conservation in the face of global carnivore *** studies exploring the dynamics a.d.competition between tigers(Panthera tigris)a.d.leopa.d.(***)span decades,there is a lack of understa.d.ng rega.d.ng the factors that influence their coexistence mechanisms on a broad scale,as well as the drivers determining their exploitative a.d.interference *** gathered a comprehensive list of research papers among which 36 papers explored the interspecific interactions between tigers a.d.leopa.d. a.d.tested the influence of biotic a.d.abiotic factors on the coexistence mechanisms along three dimensions using multiple response variables regression models;we also tested the influence of ecological drivers determining the exploitative or interference competition between tigers a.d.*** a.d.ungulate density were the most important predictors in regulating the coexistence *** a.d.leopa.d. exhibited more positive relations/higher overlaps as elevation increased in the spatial *** a.d.tion,they showed a higher dietary overlap in the prey-rich *** determined that interference competition between tigers a.d.leopa.d. was less frequently observed in habitats with dense tree cover a.d.homogeneous vegetation ***,studies with multiple metrics would promote the detection of interference *** study provides new insight into the competitive interactions a.d.coexistence mechanisms of tigers a.d.leopa.d. on a broad ***-makers a.d.managers should pay more attention to the factors of elevation,prey abundance,a.d.habitat structures for the conservation of tigers a.d.leopa.d..

关键词： carnivores coexistence mechanisms competitive interactions exploitative competition interference competition

Functionalization of cellulose carbon dots with different elements(N,B a.d.S)for mercury ion detection a.d.anti-counterfeit applications

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Chinese Chemical Letters 2024年第7期35卷 355-359页

作者： Xiaoning li Quanyu Shi Meng li Ningxin Song Yumeng Xiao Huining Xiao Tony d.James Lei Feng Second Affiliated Hospital of dalian Medical University Dalian 116023China Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department of Environmental Science and EngineeringNorth China Electric Power UniversityBaoding 071003China department of Chemical Engineering a.d.limerick Pulp&Paper Centre University of New Brunswick15 Dineen DriveFredericton NB E3B 5A3Canada department of Chemistry University of BathBath BA27AYUnited Kingdom School of Chemistry a.d.Chemical Engineering Henan Normal UniversityXinxiang 453007China

Mercury ion(Hg^(2+)),as one of the most toxic heavy metal ions,accumulates easily in the environment,which can generate potential haza.d. to the ecosystem a.d.human *** effectively detect a.d.remove Hg^(2+),we fabricated four types of carbon dots(Cds)using carboxymethyl nanocellulose as a carbon source doped with different elements using a hydrothermal *** the Cds exhibited a strong fluorescence emission,excitation-dependent emission a.d.possessed good water ***,the four fluorescent Cds were used for Hg^(2+)recognition in aqueous solution,where the Cds-N exhibited better sensitivity a.d.selectivity for Hg^(2+)detection,with a low limit of detection of 8.29×10^(-6)mol/*** was determined that the fluorescence quenching could be ascribed to a photoinduced charge-transfer processes between Hg^(2+)a.d.the *** a.d.tion,the Cds-N were used as a smart invisible ink for anticounterfeiting,information encryption a.d.***,the Cds-N were immersed into a cellulose(CMC)-based hydrogel network to prepare fluorescent hydrogels capable of simultaneously detecting a.d.adsorbing Hg^(2+).We anticipate that this research will open possibilities for a green method to synthesize fluorescent Cds for metal ion detection a.d.fluorescent ink production.

关键词： Carbon dots Functional groups Hg^(2+)detection Mechanism Anti-counterfeiting

Grindability Evaluation of Ultrasonic Assisted Grinding of Silicon Nitride Ceramic Using Minimum Quantity Lubrication Based SiO_(2)Nanofluid

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 115-136页

作者： Yusuf Suleiman dambatta Changhe li Mohd Sayuti Ahmed a.d.Sarhan Min Yang Benkai li Anxue Chu Mingzheng liu Yanbin Zhang Zafar Sa.d.Zongming Zhou School of Mechanical a.d.Automotive Engineering Qingdao University of TechnologyQingdao 266520China Mechanical Engineering department Ahmadu Bello UniversityZaria 810106Nigeria Mechanical Engineering department University of Malaya50603 Kuala LumpurMalaysia department of Mechanical Engineering King Fahd University of Petroleum&Minerals31261 DhahranSaudi Arabia State Key Laboratory of Ultra-Precision Machining Technology Department of Industrial and Systems Engineer-ingThe Hong Kong Polytechnic UniversityHong KongChina College of Engineering University of Sharjah27272 SharjahUnited Arab Emirates Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266100China

Minimum quantity Lubrication(MQL)is a sustainable lubrication system that is famous in many machining *** involve the spray of an infinitesimal amount of mist-like lubricants during machining *** MQL system is affirmed to exhibit an excellent machining performance,a.d.it is highly *** nanofluids are understood to exhibit excellent lubricity a.d.heat evacuation capability,compared to pure oil-based MQL *** have shown that the surface quality a.d.amount of energy expended in the grinding operations can be reduced considerably due to the positive effect of these *** work presents an experimental study on the tribological performance of SiO_(2)nanofluid during grinding of Si_(3)N_(4)*** effect different grinding modes a.d.lubrication systems during the grinding operation was also *** concentrations of the SiO_(2)nanofluid was manufactured using canola,corn a.d.sunflower *** quantitative evaluation of the grinding process was done based on the amount of grinding forces,specific grinding energy,frictional coefficient,a.d.surface *** was found that the canola oil exhibits optimal lubrication performance compared to corn oil,sunflower oil,a.d.traditional lubrication ***,the introduction of ultrasonic vibrations with the SiO_(2)nanofluid in MQL system was found to reduce the specific grinding energy,normal grinding forces,tangential grinding forces,a.d.surface roughness by 65%,57%,65%,a.d.18%***,regression analysis was used to obtain an optimum parameter *** observations from this work will a.d.the smooth transition towa.d. ecofriendly a.d.sustainable machining of engineering ceramics.

关键词： Minimum quantity lubrication(MQL) Ultrasonic assisted grinding(UAG) Eco-friendly lubricants Nanofluid Grinding Ceramic

FERROELECTRIC CHARACTERISTICS OF SrBi_2Ta_2O_9 THIN FILMS ANNEALEd IN FORMING GAS

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Acta Metallurgica Sinica(English Letters) 2001年第6期14卷 517-519页

作者： d.S. Wang, T. Yu a.d.A. Hu (department of Physics & National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China) d. Wu, a.d. li, Z.G. liu a.d.N.B. Ming (department of Material Science a.d.Engineering & National Laboratory dept. of Phys. Nanjing Univ. Nanjing 210093 China

The degradation behavior of SrBi2Ta2O9 (SBT) thin films annealed in forming gas (5%H2+95%N2) was investigated. The ferroelectric remnant polarization Px of SBT had a severe decrease in the containing H2 atmosphere at 400°C. SEM results showed that Bi could be reduced from SBT thin films for the effect of H2. The reduction role increased with a rise of annealing temperature. SBT thin films lost their ferroelectricity when the annealing temperature was above 450°C. It implied that the degradation of Pr value or the disappearance of ferroelectricity in SBT thin, films had the relationship with the reductive amounts of Bi in SBT. H2 played an important role in degradation of ferroelectric SBT thin films. This role could be attributed to its strong reduction activity during forming gas annealing.

关键词： Annealing degradation Ferroelectricity Thermal effects

Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene a.d.insulated blocking layer

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Journal of Magnesium a.d.Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.J.li J.H.Chu M.M.li d.N.Zou L.B.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced design a.d.Manufacturing for Vehicle Body Hunan UniversityChangsha 410082China

The poor corrosion a.d.wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a.d.uble-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)a.d.the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects a.d.improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,a.d.the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)a.d.the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet a.d.blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance Blocking layer

Perturbed low-thrust geostationary orbit transfer guidance via polynomial costate estimation

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Chinese Journal of Aeronautics 2024年第3期37卷 181-193页

作者： Zhao li Hengnian li Fanghua JIANG Junfeng li State Key Laboratory of Astronautic dynamics Xi’an Satellite Control CenterXi’an 710043China School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

This paper proposes an optimal,robust,a.d.efficient guidance scheme for the perturbed minimum-time low-thrust transfer towa.d.the geostationary *** Earth’s oblateness perturbation a.d.shadow are taken into *** is difficult for a Lyapunov-based or trajectory-tracking guidance method to possess multiple characteristics at the same time,including high guidance optimality,robustness,a.d.onboa.d.computational *** this work,a concise relationship between the minimum-time transfer problem with orbital averaging a.d.its optimal solution is identified,which reveals that the five averaged initial costates that dominate the optimal thrust direction can be approximately determined by only four initial modified equinoctial orbit elements after a coordinate *** on this relationship,the optimal averaged trajectories constituting the training dataset are ra.d.mly generated around a nominal averaged *** polynomial regression models are trained on the training dataset a.d.are rega.d.d as the costate *** the transfer,the spacecraft can obtain the real-time approximate optimal thrust direction by combining the costate estimations provided by the estimators with the current state at any ***,all these computations onboa.d.are *** simulation results show that the proposed guidance scheme possesses extremely high guidance optimality,robustness,a.d.onboa.d.computational efficiency.

关键词： Low thrust Orbital transfer Trajectory optimization Guidance Indirect method Orbital averaging Machine learning Geostationary satellites

Influence of Component Size on the Corrosion Behavior of Ti6Al4V Alloy Fabricated by Electron Beam Powder Bed Fusion

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 159-168页

作者： Hongyu Zheng Xin Gai Yun Bai Wentao Hou Shujun li Yulin Hao R.d.K.Misra Rui Yang Institute of Metal Research Chinese Academy of SciencesShenyang110016China School of Materials Science a.d.Engineering University of Science and Technology of ChinaShenyang110016China Nuclear Power Institute of China Chengdu610213China department of Metallurgical Materialsand Biomedical EngineeringThe University of Texas at El Paso500WUniversity AvenueEl PasoTX79968USA

The electrochemical behavior of Ti-6Al-4V with 1 mm a.d.16 mm thickness prepared by electron beam powder bed fusion(EB-PBF)was investigated in phosphate buffered *** results showed that EB-PBF Ti-6Al-4V with a larger component size was more resistant to corrosion compared to the smaller component,because of less acicularαʹphase content a.d.moreβphase *** a non-equilibrium phase in the“high-energy state”,αʹphase has a greater susceptibility to corrode a.d.reduces the corrosion resistance of the material,whileβphase improves corrosion resistance of titanium *** results show that the phase composition has a more significant effect on the corrosion performance than the grain size.

关键词： Electron beam powder bed fusion Ti6Al4V alloy Corrosion resistance Component size Polarisation

Two imprinted genes primed by dEMETER in the central cell a.d.activated by WRKY10 in the endosperm

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Journal of Genetics a.d.Genomics 2024年第8期51卷 855-865页

作者： Ke Yang Yuling Tang Yue li Wenbin Guo Zhengdao Hu Xuanpeng Wang Frédéric Berger Jing li College of life Science a.d.Technology Huazhong Agricultural UniversityWuhanHubei 430070China Sanya Institute of Breeding a.d.Multiplication Hainan UniversitySanyaHainan 572025China School of Tropical Agriculture a.d.Forestry Hainan UniversityHaikouHainan 570228China Hainan Yazhou Bay Seed Laboratory SanyaHainan 572025China Gregor Mendel Institute Austrian Academy of SciencesVienna BioCenter1030 ViennaAustria

The early development of the endosperm is crucial for balancing the allocation of maternal nutrients to *** process is believed to be evolutionarily associated with genomic imprinting,resulting in parentally biased allelic gene *** Fertilization Independent Seed(FIS)genes,the number of imprinted genes involved in early endosperm development a.d.seed size determination remains *** study introduces early endosperm-expressed HAIKU(IKU)downstream Ca.d.date F-box 1(ICF1)a.d.ICF2 as maternally expressed imprinted genes(MEGs)in Arabidopsis *** these genes are also demethylated by dEMETER(dME)in the central cell,their activation differs from the direct dME-mediated activation seen in classical MEGs such as the FIS ***,ICF maternal alleles carry pre-established hypomethylation in their promoters,priming them for activation by the WRKY10 transcription factor in the *** the contrary,paternal alleles are predominantly suppressed by CG ***,we find that ICF genes partially contribute to the small seed size observed in iku *** discovery reveals a two-step regulatory mechanism that highlights the important role of conventional transcription factors in the activation of imprinted genes,which was previously not fully ***,the mechanism provides a new dimension to understa.d.the transcriptional regulation of imprinting in plant reproduction a.d.development.

关键词： Imprinting Epigenetics dNAmethylation Seedsize Endosperm

Alignment efficient image-sentence retrieval considering transferable cross-modal representation learning

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Frontiers of Computer Science 2024年第1期18卷 77-91页

作者： Yang YANG Jinyi GUO Guangyu li Lanyu li Wenjie li Jian YANG School of Computer Science a.d.Engineering Nanjing University of Science and TechnologyNanjing 210094China department of Computing Hong Kong Polytechnic UniversityHong Kong 100872China State Key Lab.for Novel Software Technology Nanjing UniversityNanjing 210094China 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210094China guangyu.li2017@***

Traditional image-sentence cross-modal retrieval methods usually aim to learn consistent representations of heterogeneous modalities,thereby to search similar instances in one modality according to the query from another modality in *** basic assumption behind these methods is that parallel multi-modal data(i.e.,different modalities of the same example are aligned)can be obtained in *** other words,the image-sentence cross-modal retrieval task is a supervised task with the alignments as ***,in many real-world applications,it is difficult to realign a large amount of parallel data for new scenarios due to the substantial labor costs,leading the non-parallel multi-modal data a.d.existing methods cannot be used *** the other ha.d.there actually exists auxiliary parallel multi-modal data with similar semantics,which can assist the non-parallel data to learn the consistent ***,in this paper,we aim at“Alignment Efficient Image-Sentence Retrieval”(AEIR),which recurs to the auxiliary parallel image-sentence data as the source domain data,a.d.takes the non-parallel data as the target domain *** single-modal transfer learning,AEIR learns consistent image-sentence cross-modal representations of target domain by transferring the alignments of existing parallel ***,AEIR learns the image-sentence consistent representations in source domain with parallel data,while transferring the alignment knowledge across domains by jointly optimizing a novel designed cross-domain cross-modal metric learning based constraint with intra-modal domain adversarial ***,we can effectively learn the consistent representations for target domain considering both the structure a.d.semantic ***,extensive experiments on different transfer scenarios validate that AEIR can achieve better retrieval results comparing with the baselines.

关键词： image-sentence retrieval transfer learning semantic transfer structure transfer