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Deep soil microbial carbon metabolic function is important but often neglected:a study on the songnen Plain reed wetland,Northeast China

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Fundamental Research 2023年第6期3卷 833-843页

作者： Zhen-Di Liu Yan-Yu song Xiu-Yan Ma Jia-Bao Yuan Yan-Jing Lou Chen Yang Hao-Ran Tang chang-chun song Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China Xi'an University of Architecture and Technology Xi'an 710055China School of Hydraulic Engineering Dalian University of TechnologyDalian 116024China

Soil microbial carbon metabolism is critical in wetland soil carbon cycling,and is also a research hotspot at ***,most studies focus on the surface soil layer in the wetlands and the microorganisms associated with this *** this study,0-75 cm soil profiles were collected from five widely separated reed wetlands in the songnen Plain,which has a large number of middle-high latitude inland saline-sodic *** Biolog-ECO method was used to determine the carbon metabolic activity and functional diversity of soil *** results showed that soil carbon metabolic activity decreased with increasing soil *** carbon metabolic activity of soil microorganisms in the 60-75 cm layer was approximately 57.41%-74.60%of that in the 0-15 cm *** soil microbial Shannon index and utilization rate of amines decreased with an increase in soil depth,while the Evenness index and utilization rate of polymers tended to increase with soil *** organic carbon(DOC)is the most important factor affecting microbial carbon source utilization preference,because microorganisms mainly obtain the carbon source from *** result of the correlation analysis showed that the soil microbial carbon metabolic activity,Shannon index,and Evenness index significantly correlated with soil total carbon(TC),microbial biomass carbon(MBC),DOC,total nitrogen(TN),ammonium nitrogen(NH_(4)^(+)-N),nitrate nitrogen(NO_(3)_(−)-N)contents,and electrical conductivity(EC).This study emphasized the important role of microbial carbon metabolic function in deep soil.

关键词： Soil profiles Soil microbial functional diversity Biolog-ECO Substrate utilization Wetland

RING-MORPHOSTRUCTURES OF THE AMUR-songHUA-HUANGHE LINEAMENT (EASTERN MARGIN OF ASIA)

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Chinese Geographical Science 2000年第4期10卷 61-68页

作者： A P Kulakov Shan-wen Qiu E A Miasnikov Xi-kui Wang S M Tashchi Hua-chang Zhao chang-chun song

： The“ ring-morphostructures” (RM) are the object of this study. They are one of the most significant element of lineament’s structure and unknown for the majority of investigations. RM are numerous to lineament’s zone: they have different size (from 10-20km to 500-800km in diameter), structure, age, geological history and have been divided into several classes on the most important signs. They have a spatial-genetic connection Amur-songhua-Huanghe lineament (ASHL) and had been developed simultaneously with it. The RM exerted an essential influence on the geologic-geomorphological structure, evolution and geodynamics of lineament. The main factor of evolution of lineament is a long geological process of extension of the earth’s crust which is a result of the expanding earth.

关键词： ring-morphostructure lineament structure East AsiP

Inverse-time Backup Protection Based on Unified Characteristic Equation for Distribution Networks with High Proportion of Distributed Generations

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 202-212页

作者： Nana chang Guobing song Zhongxue chang Yuping Zheng Xingang Yang the School of Electrical Engineering Xi’an Jiaotong UniversityXi’anChina State Key Laboratory of Smart Grid Protection and Control NARI Group CorporationNanjingChina Electric Power Research Institute of State Grid Shanghai Electric Power Company ShanghaiChina

The setting work of backup protection using steady-state current is tedious,and mismatches occasionally occur due to the increased proportion of distributed generations(DGs)connected to the power ***,there is a practical need to study a backup protection technology that does not require step-by-step setting and can be adaptively *** paper proposes an action sequence adaptive to fault positions that uses only positive sequence fault component(PSFC)*** the influence of DGs,the unified time dial setting can be obtained by selecting specific *** protection performance is improved by using the adjacent upstream and downstream protections to meet the coordination time interval in the case of metallic faults at the near-and far-ends of the ***,the expression and implementation scheme for inverse-time backup protection(ITBP)based on the unified characteristic equation is *** results show that this scheme can adapt to DG penetration scenarios and can realize the adaptive coordination of multi-level relays.

关键词： Inverse-time backup protection(ITBP) distributed generation(DG) positive sequence fault component(PSFC)voltage unified characteristic equation adaptive coordination

Photoluminescent nickel(Ⅱ)carbene complexes with ligand-to-ligand charge-transfer excited states

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Chinese Chemical Letters 2024年第1期35卷 357-360页

作者： chun-Liang Hou Jia-Xi song Xiaoyong chang Yong Chen Key Laboratory of Photochemical Conversion and Optoelectronic Materials&CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China

While nickel(II)complexes have been widely used as catalysts for carbon-carbon coupling reactions,the exploration of their photophysical and photochemical properties is still in the ***,a series of square-planar Ni(II)complexes[(diNHC)NiX2]bearing chelating benzimidazole-based bis(N-heterocyclic carbene)ligands and varying anionic coligands(1,X=Cl;2,X=Br;3,X=I)are synthesized and structurally *** solid state,both 1 and 2 exhibit orange-red photoluminescence under ambient *** photophysical and electrochemical measurements along with density functional theory(DFT)calculations reveal that the low-energy emissions can be attributed to singlet excited states with ligand-to-ligand charge-transfer(LLCT)*** work suggests that strong-field N-heterocyclic carbene ligands play a crucial role to achieve the luminescence of Ni(II)complexes.

关键词： Nickel(II)complexes N-Heterocyclic carbene Luminescence Ligand-to-ligand charge-transfer character Low-lying d-d excited states

A deep learning interatomic potential suitable for simulating radiation damage in bulk tungsten

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Tungsten 2024年第2期6卷 304-322页

作者： chang-Jie Ding Ya-Wei Lei Xiao-Yang Wang Xiao-Lin Li Xiang-Yan Li Yan-Ge Zhang Yi-chun Xu chang-song Liu Xue-Bang Wu Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Science Island University of Science and Technology of ChinaHefei 230026China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China

So far, it has been a challenge for existing interatomic potentials to accurately describe a wide range of physical properties and maintain reasonable efficiency. In this work, we develop an interatomic potential for simulating radiation damage in body-centered cubic tungsten by employing deep potential, a neural network-based deep learning model for representing the potential energy surface. The resulting potential predicts a variety of physical properties consistent with first-principles calculations, including phonon spectrum, thermal expansion, generalized stacking fault energies, energetics of free surfaces, point defects, vacancy clusters, and prismatic dislocation loops. Specifically, we investigated the elasticity-related properties of prismatic dislocation loops, i.e., their dipole tensors, relaxation volumes, and elastic interaction energies. This potential is found to predict the maximal elastic interaction energy between two 1/2 loops better than previous potentials, with a relative error of only 7.6%. The predicted threshold displacement energies are in reasonable agreement with experimental results, with an average of 128 eV. The efficiency of the present potential is also comparable to the tabulated gaussian approximation potentials and modified embedded atom method potentials, meanwhile, can be further accelerated by graphical processing units. Extensive benchmark tests indicate that this potential has a relatively good balance between accuracy, transferability, and efficiency.

关键词： Machine learning Deep learning Interatomic potential Radiation damage Tungsten

Mn-modified nitrogen-doped Pt-based electrocatalyst for efficient oxygen reduction in aluminum-air batteries

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Nano Research 2024年第8期17卷 7126-7135页

作者： Li Gao Yang song Xuebing Xu chang Li Chaoquan Hu State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Zhongke Nanjing Institute of Green Manufacturing Industry Nanjing 211135China

In this study,a Mn-modified Pt-based catalyst loaded on nitrogen-doped Ketjen black(Mn-Pt/NKB)is prepared using a simple ethylene glycol reduction *** size of Pt nanoparticles(NPs)is effectively controlled by doping with Mn and *** the smallest average particle size of 1.7 nm,Mn-Pt/NKB demonstrates half-wave potentials of 0.890 and 0.688 V in the alkaline and neutral electrolytes,respectively,which are superior to those of commercial platinum on activated carbon(Pt/C).When applied as an air cathode in aluminum-air battery,it exhibits ultra-high power densities of 190(alkaline)and 26.2 mW·cm^(−2)(neutral).Moreover,the voltage remains stable after 5 h of *** practical application performance of the Mn-Pt/NKB catalyst in an aluminum-air battery is better than that of commercial Pt/***,the oxygen reduction reaction(ORR)mechanism on surfaces with different particle sizes is analyzed using density functional *** cracking is the major pathway on the surface of the small particles with lower energy consumption of 0.5 eV,while water molecule cleavage is the major pathway on the surface of the large particles with higher energy consumption of 0.97 *** lower energy consumption of the oxygen cracking pathway further confirms the ORR mechanism for higher activity on small-sized *** study provides a direction for the rational design of Pt-based catalysts for ORR and sheds light on the commercial development of aluminum-air batteries.

关键词： oxygen reduction reaction precious metal catalysts aluminum-air battery density functional theory(DFT)calculations reaction pathway

Global Spherically Symmetric Solutions for a Coupled Compressible Navier–Stokes/Allen–Cahn System

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Acta Mathematica Sinica,English Series 2024年第8期40卷 2037-2064页

作者： chang Ming song Jian Lin ZHANG Yuan Yuan WANG Department of Applied Mathematics School of Mathematics and Information ScienceZhongyuan University of TechnologyZhengzhou 450007P.R.China

In this paper,we consider the global spherically symmetric solutions for the initial boundary value problem of a coupled compressible Navier–Stokes/Allen–Cahn system which describes the motion of two-phase viscous compressible *** prove the existence and uniqueness of global classical solution,weak solution and strong solution under the assumption of spherically symmetry condition for initial dataρ0 without vacuum state.

关键词： Diffuse interface model global solutions Navier-Stokes equations Allen-Cahn equation spherically symmetry

Mathematical Model,Numerical Simulation and Convergence Analysis of a Semiconductor Device Problem with Heat and Magnetic Influences

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 302-319页

作者： chang-feng LI Yi-rang YUAN Huai-ling song School of Economics Shandong UniversityJinan 250100China Institute of Mathematics Shandong UniversityJinan 250100China College of Mathematics and Econometrics Hunan UniversityChangsha 410082China

In this paper,the authors discuss a three-dimensional problem of the semiconductor device type involved its mathematical description,numerical simulation and theoretical *** important factors,heat and magnetic influences are *** mathematical model is formulated by four nonlinear partial differential equations(PDEs),determining four major physical *** influences of magnetic fields are supposed to be weak,and the strength is parallel to the *** elliptic equation is treated by a block-centered method,and the law of conservation is *** computational accuracy is improved one *** equations are convection-dominated,thus are approximated by upwind block-centered *** difference can eliminate numerical dispersion and nonphysical *** diffusion is approximated by the block-centered difference,while the convection term is treated by upwind ***,the unknowns and adjoint functions are computed at the same *** characters play important roles in numerical computations of conductor device *** the theories of priori analysis such as energy estimates,the principle of duality and mathematical inductions,an optimal estimates result is *** a composite numerical method is shown for solving this problem.

关键词： three-dimensional conductor device problem with heat and magnetic influences upwind blockcentered differences elemental conservation of mass numerical analysis

Assembly of highly efficient aqueous light-harvesting system from sequence-defined peptoids for cytosolic microRNA detection

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Nano Research 2024年第2期17卷 788-796页

作者： Yang song Xiaoli Cai Mingming Wang Dan Du Yuehe Lin chun-Long Chen Department of Mechanical and Materials Engineering Washington State UniversityPullmanWA 99164USA Division of Physical Sciences Pacific Northwest National LaboratoryRichlandWA 99352USA Department of Chemical Engineering University of WashingtonSeattleWA 98195USA

Precisely controlled spatial distributions of artificial light-harvesting systems in aqueous media are of significant importance for mimicking natural light-harvesting systems;however,they are often restrained by the solubility and the aggregation-caused quenching effect of the hydrophobic ***,we report one highly efficient artificial light-harvesting system based on peptoid nanotubes that mimic the hierarchical cylindrical structure of natural *** high crystallinity of these nanotubes enabled the organization of arrays of donor chromophores with precisely controlled spatial distributions,favoring an efficient Förster resonance energy transfer(FRET)process in aqueous *** FRET system exhibits an extremely high efficiency of 98.6%with a fluorescence quantum yield of 40%and an antenna effect of *** further demonstrated the use of this artificial light-harvesting system for quantifying miR-210 within cancer *** fluorescence intensity ratio of donor to acceptor is linearly related to the concentration of intercellular miR-210 in the range of 3.3–156 copies/*** high sensitivity in intracellular detection of miR-210 using this artificial light-harvesting system offers a great opportunity and pathways for biological imaging and detection,and for the further creation of microRNA(miRNA)toolbox for quantitative epigenetics and personalized medicine.

关键词： light-harvesting peptoid nanotube Förster resonance energy transfer intracellular RNA detection