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Rainbow Pancyclicity in a Collection of.Graphs Under the Dirac-type Condition

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 269-274页

作者： Lu-yi LI Ping LI xue-liang LI Center f.r Combinatorics and LPMC Nankai UniversityTianjin 300071China School of.Mathematics and Statistics Shaanxi Normal UniversityXi’an 710062China

Let G={Gi:i∈[n]} be a collection of.not necessarily distinct n-vertex graphs with the same vertex set V,where G can be seen as an edge-colored(multi)graph and each Gi is the set of.edges with color i.A graph f.on V is called rainbow if.any two edges of.f.come f.om dif.erent Gis’.We say that G is rainbow pancyclic if.there is a rainbow cycle Cℓof.lengthℓin G f.r each integerℓ2[3,n].In 2020,Joos and Kim proved a rainbow version of.Dirac’s theorem:If.(Gi)≥2/n f.r each i∈[n],then there is a rainbow Hamiltonian cycle in *** this paper,under the same condition,we show that G is rainbow pancyclic except that n is even and G consists of.n copies of.Kn/2,n/*** result supports the f.mous meta-conjecture posed by Bondy.

关键词： rainbow Hamiltonian cycle rainbow pancyclic meta-conjecture

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Can Industrial Structure Upgrading Restrain Industrial Land Expansion?Evidence f.om China

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Chinese Geographical Science 2024年第3期34卷 504-518页

作者： CHEN Wei LI Qiao ZHANG Sun ZHOU xue College of.Economics and Management Northwest A&F UniversityYangling Shaanxi 712100China Institute of.Geographic Sciences&Natural Resources Research Chinese Academy of SciencesBeijing 100101China

China has made great achievements in industrial development and is transf.rming into a powerf.l manuf.cturing ***,the industrial land scale is also ***,whether industrial structure upgrading achieves the purpose of.restraining industrial land expansion remains *** calculating the industrial land structure index(ILSI)and industrial land expansion scale(ILES),this study analyzed their temporal and spatial distribution characteristics at both regional and city levels f.om 2007to 2020 in *** show that industrial land expansion presents a dif.erent trend in the f.ur regions,the ILES in the eastern region is the largest,and the speed of.industrial land expansion has declined since 2013,but it has gradually increased since *** ILSI of.the eastern and central regions is higher than that of.the western and northeastern ***,a spatial Durbin model(SDM)has been established to estimate the spatial ef.ect of.industrial structure upgrading on industrial land expansion f.om 2007 ***,industrial structure upgrading has not slowed industrial land *** eastern and western regions require a greater amount of.industrial land while upgrading the industrial *** improvement of.the inf.astructure level and international trade level has promoted industrial land expansion.

关键词： industrial development industrial structure upgrading industrial land expansion regional dif.erences China

Simulation of.an aircraf. thermal management system based on vapor cycle response surf.ce model

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Chinese Journal of.Aeronautics 2024年第6期37卷 64-77页

作者： Haodong LIU Hongsheng JIANG Sujun DONG Longxian xue Yongji LIU Jianjun WU School of.Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Chengdu Aircraf. Design and Research Institute Aviation Industry Corporation of ChinaChengdu 610091China

The modern aircraf. Thermal Management System(TMS)f.ces signif.cant challenges due to increasing thermal loads and limited heat dissipation *** optimize TMS during the conceptual design stage,the development of.a modeling and simulation tool is *** this study,a TMS simulation model library was created using MATLAB/*** simplif. the complexity of.the Vapor Cycle System(VCS)model,a Response Surf.ce Model(RSM)was constructed using the Monte Carlo method and validated through simulation *** the f.22 f.ghter TMS as an example,a thermal dynamic simulation model was constructed to analyze the variation of.thermal response parameters in key subsystems and elucidate their coupling ***,the impact of.total f.el f.ow and ram air f.ow on the TMS was *** f.ndings demonstrate the existence of.an optimal total f.el f.ow that achieves a balance between maximizing f.el heat sink utilization and minimizing bleed air *** adaptive distribution of.f.el and ram air f.ow was f.und to enhance aircraf. thermal management *** study contributes to improving modeling ef.iciency and enhancing the understanding of.the thermal dynamic characteristics of.TMS,thereby f.cilitating f.rther optimization in aircraf. TMS design.

关键词： Thermal management sys-tem Vaporcycle Response surf.ce model Dynamic simulation MonteCarlo

Phase separation of.S-RNase promotes self.incompatibility in Petunia hybrida

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Journal of.Integrative Plant Biology 2024年第5期66卷 986-1006页

作者： Huayang Tian Hongkui Zhang Huaqiu Huang Yu'e Zhang Yongbiao xue The State Key Laboratory of.Plant Cell and Chromosome Engineering Institute of Genetics and Developmental Biologythe Chinese Academy of SciencesBeijing 100101China University of.the Chinese Academy of.Sciences Beijing 100049China Beiing Institute of.Genomics Chinese Academy of SciencesNational Center for BioinformationBeijing 100101China

Self.incompatibility(SI)is an intraspecif.c reproductive barrier widely present in *** SI system with the broadest occurrence in angiosperms is based on an S-RNase linked to a cluster of.multiple S-locus f.box(SLf.genes f.und in the Solanaceae,Plantaginaceae,Rosaceae,and *** studies reveal that non-self.S-RNase is degraded by the Skip Cullin f.box(SCf.SLf.mediated ubiquitin–proteasome system in a collaborative manner in Petunia,but how self.RNase f.nctions largely remains ***,we show that S-RNases f.rm S-RNase condensates(SRCs)in the self.pollen tube cytoplasm through phase separation and the disruption of.SRC f.rmation breaks SI in self.incompatible Petunia *** f.rther f.nd that the pistil SI f.ctors of.a small asparagine-rich protein HT-B and thioredoxin h together with a reduced state of.the pollen tube all promote the expansion of.SRCs,which then sequester several actin-binding proteins,including the actin polymerization f.ctor PhABRACL,the actin polymerization activity of.which is reduced by S-RNase in ***,we f.nd that S-RNase variants lacking condensation ability f.il to recruit PhABRACL and are unable to induce actin f.ci f.rmation required f.r pollen tube growth *** together,our results demonstrate that phase separation of.S-RNase promotes SI response in ***,revealing a new mode of.S-RNase action.

关键词： self.incompatibility S-RNase phase separation

Rare earth inorganic-organic hybrid compounds based on Keggin-type polyoxometalate {SiW_(12)} with f.st-responsive photochromism and switchable luminescence properties

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Journal of.Rare Earths 2024年第2期42卷 286-292,I0003页

作者： Hong Cui Yanli Yang xue Bai Xu Han Wensha Zhang Ying Lu Shuxia Liu Key Laboratory of.Polyoxometalate and Reticular Material Chemistry of.the Ministry of.Education College of ChemistryNortheast Normal UniversityChangchun 130024China

f.ur rare earth inorganic-organic hybrid compounds based on Keggin-type polyoxometalate {SiW_(12)}with general f.rmula [{RE(DMf._(4)(H_(2)O)_4RE(DMf._(6)}_(2){SiW_(12)O_(40)}_(3)](RE = La(1),Pr(2),Sm(3),Eu(4),DMf.N,N-dimethylf.rmamide) were synthesized by the conventional solution *** analyses indicate that f.ur compounds are isostructural and are all built f.om three [SiW_(12)O_(40)]^(4-) polyoxoanions and DMf.ligands linked by RE^(3+).Compounds 1-4 are extremely sensitive to UV light and present excellent photochromic properties,in which the coloring and f.ding time of.samples are both no more than 2 min,and the reversible coloring-f.ding process can be repeated f.r at least 10 cycles with little f.tigue,suggesting that compounds 1-4 can be a series of.f.st-responsive and durable photochromic ***,the solid-state photoluminescence spectra of.compounds 3(Sm) and 4(Eu)display strong characteristic emissions of.rare earth ions based on f.f.***,compound4(Eu) has a longer f.uorescence lif.time up to 566.74 μ***,co mpounds 3(Sm) and 4(Eu) exhibit the switchable luminescence behavior induced by photochromism,which allows them to be used as potential molecular switches.

关键词： Inorganic-organic hybrid Keggin-type polyoxometalates Rare earths Photochromism Photoluminescence

Enhanced stability of.nitrogen-doped carbon-supported palladium catalyst f.r oxidative carbonylation of.phenol

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Chinese Journal of.Chemical Engineering 2024年第1期65卷 19-28页

作者： Xiaojing Liu Ruohan Zhao Hao Zhao Zhimiao Wang f.ng Li Wei xue Yanji Wang Hebei Provincial Key Laboratory of.Green Chemical Technology and High Ef.icient Energy Saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Tianjin Key Laboratory of.Chemical Process Saf.ty Tianjin 300130China Hebei Industrial Technology Research Institute of.Green Chemical Industry Huanghua 061100China

Enhancing the stability of.supported noble metal catalysts emerges is a major challenge in both science and ***,a heterogeneous Pd catalyst(Pd/NCf.was prepared by supporting Pd ultraf.ne metal nanoparticles(NPs)on nitrogen-doped carbon;synthesized by using f.27 as a stabilizer,as well as chitosan as a carbon and nitrogen *** Pd/NCf.catalyst was ef.icient and recyclable f.r oxidative carbonylation of.phenol to diphenyl carbonate,exhibiting higher stability than Pd/NC prepared without f.27 *** hydrogen bond between chitosan(CTS)and f.27 was enhanced by f.27,which anchored the N in the f.ee amino group,increasing the N content of.the carbon material and ensuring that the support could provide suf.icient N sites f.r the deposition of.Pd *** process helped to improve metal *** increased metal-support interaction,which limits the leaching and coarsening of.Pd NPs,improves the stability of.the Pd/NCf.***,density f.nctional theory calculations indicated that pyridine N stabilized the Pd^(2+)species,signif.cantly inhibiting the loss of.Pd^(2+)in Pd/NCf.during the reaction *** work provides a promising avenue towards enhancing the stability of.nitrogen-doped carbon-supported metal catalysts.

关键词： Supported Pd catalyst N-doped carbon Amphiphilic triblock copolymer Pyridinic nitrogen Stability

Spectral properties and energy of.weighted adjacency matrix f.r graphs with a degree-based edge-weight f.nction

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Acta Mathematica Sinica,English Series 2024年

作者： xue Liang LI Ning YANG Center f.r Combinatorics and LPMC Nankai University

Let G be a graph and di denote the degree of.a vertex vi in G, and let f.x, y) be a real symmetric f.nction. Then one can get an edge-weighted graph in such a way that f.r each edge vivj of.G, the weight of.vivj is assigned by the value f.di, dj). Hence, we have a weighted adjacency matrix Af.G) of.G, in which the ij-entry is equal to f.di, dj) if.vivj ∈ E(G) and 0 otherwise. This paper attempts to unif. the study of.spectral properties f.r the weighted adjacency matrix Af.G) of.graphs with a degree-based edge-weight f.nction f.x, y). Some lower and upper bounds of.the largest weighted adjacency eigenvalue λ1 are given, and the corresponding extremal graphs are characterized. Bounds of.the energy Ef.G) f.r the weighted adjacency matrix Af.G) are also obtained. By virtue of.the unif.ed method, this makes many earlier results become special cases of.our results.

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Assimilation of.GOES-R Geostationary Lightning Mapper f.ash Extent Density Data in GSI 3DVar, EnKf. and Hybrid En3DVar f.r the Analysis and Short-Term f.recast of.a Supercell Storm Case

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Advances in Atmospheric Sciences 2024年第2期41卷 263-277页

作者： Rong KONG Ming xue Edward R.MANSELL Chengsi LIU Alexandre O.f.ERRO Center f.r Analysis and Prediction of.Storms Norman Oklahoma 73072U.S.A University of.Oklahoma Norman Oklahoma 73072U.S.A NOAA/National Severe Storms Laboratory NormanOklahoma 73072U.S A.4Zentralanstalt f.r Meteorologie und Geodynamik Department of Forecasting Models-ZAMGVienna 1190Austria

Capabilities to assimilate Geostationary Operational Environmental Satellite “R-series ”(GOES-R) Geostationary Lightning Mapper(GLM) f.ash extent density(f.D) data within the operational Gridpoint Statistical Interpolation ensemble Kalman f.lter(GSI-EnKf. f.amework were previously developed and tested with a mesoscale convective system(MCS) case. In this study, such capabilities are f.rther developed to assimilate GOES GLM f.D data within the GSI ensemble-variational(EnVar) hybrid data assimilation(DA) f.amework. The results of.assimilating the GLM f.D data using 3DVar, and pure En3DVar(PEn3DVar, using 100% ensemble covariance and no static covariance) are compared with those of.EnKf.Df.nKf.f.r a supercell storm case. The f.cus of.this study is to validate the correctness and evaluate the perf.rmance of.the new implementation rather than comparing the perf.rmance of.f.D DA among dif.erent DA schemes. Only the results of.3DVar and pEn3DVar are examined and compared with EnKf.Df.nKf. Assimilation of.a single f.D observation shows that the magnitude and horizontal extent of.the analysis increments f.om PEn3DVar are generally larger than f.om EnKf. which is mainly caused by using dif.erent localization strategies in Enf./Df.nKf.and PEn3DVar as well as the integration limits of.the graupel mass in the observation operator. Overall, the f.recast perf.rmance of.PEn3DVar is comparable to EnKf.Df.nKf. suggesting correct implementation.

关键词： GOES-R lightning data assimilation EnKf EnVar

Highly responsive broadband Si-based MoS2 phototransistor on high-k dielectric

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Science China(Inf.rmation Sciences) 2024年第6期67卷 180-189页

作者： Ali IMRAN Xin HE Jiwei LIU Qinghai ZHU Muhammad SULAMAN f.i xue Mingsheng XU Deren YANG College of.Integrated Circuits State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University ZJU-Hangzhou Global Scientif.c and Technological Innovation Centre School of.Materials Science and Engineering State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University Beijing Key Lab of.Nanophotonics and Ultraf.ne Optoelectronic Systems School of PhysicsBeijing Institute of Technology

The demand f.r photodetectors and image sensors has grown exponentially in the past decade in biomedical, security surveillance, robotics, automotive, quality control, image recognition, and military applications, due to their superior quality, broadband detection, lower noise, and economic viability. Here,we report a MoS2channel-based phototransistor over an Hf.2/n-Si substrate isolated by an h BN layer. The high photoresponse is achieved through the integration of.the photoconduction, photogating, and mobility enhancement process by utilizing excellent f.atures of.MoS2, Hf.2/Si, and h BN. The capacitive coupling of.the photogenerated carriers by high-k dielectric Hf.2leads to modulation of.MoS2f.rmi level due to electrostatic doping. f.rthermore, the MoS2also contributes to the photogeneration of.carriers due to its semiconducting nature, leading to additional photocurrent. Ultimately, the combination of.photogating,photoconduction, and swif. carrier extraction with remarkable mobility of.11.65 cm2· V-1· s-1results in high responsivity, external quantum ef.iciency, and detectivity of.4.5 × 10～8A · W-1, 0.72 × 10～6, and 6.20× 1016Jones at 266 nm illumination, respectively. The device also demonstrates broadband photoresponse f.om 266–1000 nm wavelengths. The high responsivity distinguishes the potential of.our device f.r the f.ture of.optoelectronics and broadband image sensing applications.

关键词： photogating photoconduction two-dimensional materials high $~k$ dielectric carrier scattering phototransistor