In the present study, two models of atom occupation in LaNi4Co were put forward and corresponding valence electron structures （VESs） of these two models were investigated according to empirical electron theory （EET...In the present study, two models of atom occupation in LaNi4Co were put forward and corresponding valence electron structures （VESs） of these two models were investigated according to empirical electron theory （EET） of solids and molecules. Results demonstrate that the VES-concerned hardness factor （FH） of LaNi4Co is lower than that of LaNi5, so LaNi4Co has lower hardness, higher plasticity and improved anti-pulverization ability. In the mean time, the difference of the equilibrium hydrogen pressure between LaNiaCo and LaNi5 was analyzed in the electronic level. The analysis shows that the strength of the weakest bond net in octahedron lattice interstices of LaNi4Co is much lower than that in LaNis; consequently, LaNi4Co＇s bond net easily deforms to accommodate hydrogen so that LaNi4Co has lower equilibrium hydrogen pressure in comparison with LaNis. The results can provide some theory guide on the design of hydrogen storage alloys.展开更多
We introduce a mock galaxy catalog built for the China Space Survey Telescope(CSST)extragalactic surveys using the primary runs of the Jiutian N-body simulation suites.The catalogs are built by coupling the galaxy evo...We introduce a mock galaxy catalog built for the China Space Survey Telescope(CSST)extragalactic surveys using the primary runs of the Jiutian N-body simulation suites.The catalogs are built by coupling the galaxy evolution and assembly(GAe A)semianalytical model of galaxy formation with merger trees extracted from the simulations using the hierarchical bound-tracing(hb T+)algorithm.The spectral energy distributions(SEDs)and broadband magnitudes are computed using the neural-network-based stellar population synthesizer STARDus Te R,which is trained on radiative transfer simulations to account for detailed galaxy geometry in modeling dust obscuration.Galaxy light-cones up to z=5 are subsequently generated with the BLic light-cone builder,which interpolates the properties of galaxies over time using an optimized interpolation scheme.The resulting catalogs exhibit good convergence in many statistical properties of the galaxy population produced from two different resolution simulations.The catalogs reproduce a number of observed galaxy properties across a range of galaxy mass and redshift,including the stellar mass functions,the luminosity function,gas mass fraction,galaxy size-mass relation,and galaxy clustering.We also present the photometric and redshift distributions of galaxies expected to be observed in the CSST surveys.展开更多
We provide an overview of the Jiutian simulations,a hybrid simulation suite for the China space survey telescope(CSST)extragalactic surveys.It consists of four complementary modules:the primary runs with high resoluti...We provide an overview of the Jiutian simulations,a hybrid simulation suite for the China space survey telescope(CSST)extragalactic surveys.It consists of four complementary modules:the primary runs with high resolutions with the fiducial concordance cosmology,the emulator runs exploring the parameter uncertainties around the fiducial cosmology,the reconstruction runs intended for recovering the observed Universe position by position,and the extension runs employing extended cosmologies beyond the standard model.For the primary runs,two independent pipelines are adopted to construct subhaloes and merger trees.On top of them,four sets of mock galaxy light-cone catalogs are produced from semi-analytical models and subhalo abundance matching,providing a variety of observational properties including galaxy spectral energy distribution(SED),emission lines,lensing distortions,and mock images.The 129 emulator runs are used to train the CSST emulator,achieving one percent accuracy in predicting the matter power spectrum over k 10 h Mpc^(-1)and z 2.The reconstruction runs employ a number of subgrid baryonic models to predict the evolution and galaxy population resembling certain regions in the real Universe with constrained initial conditions,enabling controlled investigation of galaxy formation on top of structure formation.The extension runs cover models with warm dark matter,f(R)gravity,interacting dark energy,and nonzero neutrino masses,revealing differences in the cosmic structure under alternative cosmological models.We introduce the specifications for each run,the data products derived from them,the corresponding pipeline developments,and present some main tests.Using the primary runs,we also show that the subhalo peak mass functions of different levels are approximately universal.These simulations form a comprehensive and open simulation library for CSST surveys and beyond.展开更多
The adaptive optics system on the 2.16 m telescope is modeled and simulated using an ends-to-ends Monte Carlo method in this paper.Under the optimized parameters,the Strehl ratio can be increased from about 0.02 to mo...The adaptive optics system on the 2.16 m telescope is modeled and simulated using an ends-to-ends Monte Carlo method in this paper.Under the optimized parameters,the Strehl ratio can be increased from about 0.02 to more than 0.2 in the J,H and K bands with a classical adaptive optics system.Based on the simulation results,the practical system design is also considered and discussed.展开更多
基金financially supported by National Natural Science Foundations of China(Nos.51301149 and 50371059)
文摘In the present study, two models of atom occupation in LaNi4Co were put forward and corresponding valence electron structures （VESs） of these two models were investigated according to empirical electron theory （EET） of solids and molecules. Results demonstrate that the VES-concerned hardness factor （FH） of LaNi4Co is lower than that of LaNi5, so LaNi4Co has lower hardness, higher plasticity and improved anti-pulverization ability. In the mean time, the difference of the equilibrium hydrogen pressure between LaNiaCo and LaNi5 was analyzed in the electronic level. The analysis shows that the strength of the weakest bond net in octahedron lattice interstices of LaNi4Co is much lower than that in LaNis; consequently, LaNi4Co＇s bond net easily deforms to accommodate hydrogen so that LaNi4Co has lower equilibrium hydrogen pressure in comparison with LaNis. The results can provide some theory guide on the design of hydrogen storage alloys.
基金supported by the National Natural Science Foundation of China(Grant Nos.12595312,and 12573022)National Key R&D Program of China(Grant Nos.2023YFA1607800,2023YFA1607801,2023YFA1605600,and 2023YFA1605601)+10 种基金science research grants from the China Manned Space Project(Grant Nos.CMS-CSST-2021-A03,and CMS-CSST-2021-A02)111 project(Grant No.B20019)supported in part by Office of Science and Technology,Shanghai Municipal Government(Grant Nos.24DX1400100,and ZJ2023-ZD-001)the Yangyang Development Fundhas made use of the SVO Filter Profile Service“Carlos Rodrigo”,funded by MCIN/AEI/10.13039/501100011033/through grant PID2023-146210NBI00support from the Key R&D Program of Zhejiang,China(Grant No.2024SSYS0012)supported by the China Manned Space Program(Grant No.CMS-CSST-2025-A06)the National Natural Science Foundation of China(Grant No.12373009)the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-062)the Fundamental Research Funds for the Central Universitiesthe Xiaomi Young Talents Program。
文摘We introduce a mock galaxy catalog built for the China Space Survey Telescope(CSST)extragalactic surveys using the primary runs of the Jiutian N-body simulation suites.The catalogs are built by coupling the galaxy evolution and assembly(GAe A)semianalytical model of galaxy formation with merger trees extracted from the simulations using the hierarchical bound-tracing(hb T+)algorithm.The spectral energy distributions(SEDs)and broadband magnitudes are computed using the neural-network-based stellar population synthesizer STARDus Te R,which is trained on radiative transfer simulations to account for detailed galaxy geometry in modeling dust obscuration.Galaxy light-cones up to z=5 are subsequently generated with the BLic light-cone builder,which interpolates the properties of galaxies over time using an optimized interpolation scheme.The resulting catalogs exhibit good convergence in many statistical properties of the galaxy population produced from two different resolution simulations.The catalogs reproduce a number of observed galaxy properties across a range of galaxy mass and redshift,including the stellar mass functions,the luminosity function,gas mass fraction,galaxy size-mass relation,and galaxy clustering.We also present the photometric and redshift distributions of galaxies expected to be observed in the CSST surveys.
基金supported by the China Manned Space Project(Grant No.CMS-CSST-2021-A03)the National Key R&D Program of China(Grant Nos.2023YFA1607800,and 2023YFA1607801)+2 种基金the Key R&D Program of Zhejiang,China(Grant No.2024SSYS0012)the National Natural Science Foundation of China(Grant No.12303005)the Shuimu Tsinghua Scholar Program(Grant No.2022SM173)。
文摘We provide an overview of the Jiutian simulations,a hybrid simulation suite for the China space survey telescope(CSST)extragalactic surveys.It consists of four complementary modules:the primary runs with high resolutions with the fiducial concordance cosmology,the emulator runs exploring the parameter uncertainties around the fiducial cosmology,the reconstruction runs intended for recovering the observed Universe position by position,and the extension runs employing extended cosmologies beyond the standard model.For the primary runs,two independent pipelines are adopted to construct subhaloes and merger trees.On top of them,four sets of mock galaxy light-cone catalogs are produced from semi-analytical models and subhalo abundance matching,providing a variety of observational properties including galaxy spectral energy distribution(SED),emission lines,lensing distortions,and mock images.The 129 emulator runs are used to train the CSST emulator,achieving one percent accuracy in predicting the matter power spectrum over k 10 h Mpc^(-1)and z 2.The reconstruction runs employ a number of subgrid baryonic models to predict the evolution and galaxy population resembling certain regions in the real Universe with constrained initial conditions,enabling controlled investigation of galaxy formation on top of structure formation.The extension runs cover models with warm dark matter,f(R)gravity,interacting dark energy,and nonzero neutrino masses,revealing differences in the cosmic structure under alternative cosmological models.We introduce the specifications for each run,the data products derived from them,the corresponding pipeline developments,and present some main tests.Using the primary runs,we also show that the subhalo peak mass functions of different levels are approximately universal.These simulations form a comprehensive and open simulation library for CSST surveys and beyond.
文摘The adaptive optics system on the 2.16 m telescope is modeled and simulated using an ends-to-ends Monte Carlo method in this paper.Under the optimized parameters,the Strehl ratio can be increased from about 0.02 to more than 0.2 in the J,H and K bands with a classical adaptive optics system.Based on the simulation results,the practical system design is also considered and discussed.
