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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science china({1.,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2, sun weiguo1, HOU Shilin3 & feng hao4 1. institute of physics, College of Chemical Engineering, sichuan university, chengdu 61.065, china 2. institute of Theoretical physics, Xihua Normal university, Nanchong 637002, china 3. Department of physics, china Oceanography university, Qingdao 266003, china 4. College of physics, sichuan university, chengdu 61.065, china institute of {1. College of Chemical Engineering Sichuan University Chengdu China institute of Theoretical {1. Xihua Normal University Nanchong China Department of physics China Oceanography University Qingdao China College of physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Engineering Shewanella-re duce d graphene oxide aerogel biohybrid to efficiently synthesize Au nanoparticles

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Journal of Materials Science & Technology 2024年第1期168卷 50-61页

作者： Baocai Zhang Shulin Shao Huan Yu Qijing {1. Sicheng Shi Qingyuan Wu Zijie Wu Yiyu feng Yifei Wang Xi sun Deguang Wu feng Li hao Song Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin 300072China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China School of Materials Science and Engineering Tianjin UniversityTianjin 300350China College of Biological Engineering Tianjin Agricultural UniversityTianjin 300384China Department of Brewing Engineering Moutai InstituteLuban AveRenhuai 564507China

Biosynthesizing Au nanoparticles(AuNPs)from gold-bearing scraps provides a sustainable method to meet the urgent demand for ***,it remains challenging to efficiently biosynthesize AuNPs of which the diameter is less than 1. nm from a trace amount of Au^(3+)concentration at the level of tens ***,we constructed an exoelectrogenic cell(eCell)-conductive reduced-graphene-oxide aero-gel(rGA)biohybrid by assembling Shewanella sp.S1.SS1.as living biocatalyst and rGA as conductive ad-sorbent,in which Au^(3+)at trace concentrations would be enriched by the adsorption of rGA and reduced to AuNPs through the extracellular electron transfer(EET)of *** regulate the size of the synthe-sized AuNPs to 1. nm,the strain SS1.was engineered to enhance its EET,resulting in strain RS2(pYYD-P tac-ribADEHC&pHG1.-P_(bad)-omcC in SS1..Strain RS2 was further assembled with rGA to construct the RS2-rGA biohybrid,which could synthesize AuNPs with the size of 7.62±2.82 nm from 60 ppm Au^(3+)*** eCell-rGA biohybrid integrated Au^(3+)adsorption and reduction,which enabled AuNPs biosyn-thesis from a trace amount of Au^(3+).Thus,the required Au^(3+)ions concentration was reduced by one or two orders of magnitude compared with conventional methods of AuNPs *** work devel-oped an AuNPs size regulation technology via engineering eCell’s EET with synthetic biology methods,providing a feasible approach to synthesize AuNPs with controllable size from trace level of gold ions.

关键词： Au nanoparticles Exoelectrogenic cell(e-Cell) Shewanella Synthesis biology Extracellular electron transfer Reduced graphene oxide aerogel

Decomposition of pre-existing Au–P clusters induced in situ a-Fe grains uniformization in Fe–P-based nanocrystalline alloys

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Rare Metals 2024年第10期43卷 5242-5255页

作者： Min-hao Han Cheng {1. Guo-Guo Xi Yang Meng Qiang Luo Xue-Qian Yu Wen-feng Zhang hao liu Hong-Jie Xu Tao Zhang Key Laboratory of Aerospace Materials and Performance(Ministry of Education) School of Materials Science and EngineeringBeihang University Laboratory of Functional Fiber Materials Institute of Bast Fiber CropsChinese Academy of Agricultural Science School of Materials Science and Engineering Jiangsu Key Laboratory for Advanced Metallic MaterialsSoutheast University institute for Advanced Materials North China Electric Power University Center for Advanced Analysis and Computational Science Zhengzhou University

In Fe-based amorphous-/nanocrystalline ribbons,the uniformization and refinement of a-Fe grains are key aspects for optimizing their soft magnetic and mechanical ***,the Fe–P–C–B nanocrystalline alloy system was selected for *** produced as-spun ribbons with pre-existing nanocrystals through melt-quenching and then obtained a well-distributed a-Fe nanocrystalline structure through annealing below the first crystallization onset temperature （633 K）resulting in excellent magnetic properties (saturation magnetization of 1.65 T and coercivity of 1.6 A·m-1.ultra-wide annealing temperature window （from 61. to 733 K）,and extremely high annealing stability （up to 480 min at 633 K）.Furthermore,we propose a new in situ two-step mechanism for the uniformization of a-Fe nanocrystals,which is separately induced by the decomposition of the Au–P clusters and the pre-existing a-Fe nanocrystals during *** work underscores the crucial significance of micro-alloying via metastable clusters primarily influenced by metal-phosphide interactions in the process of refining a-Fe ***,i introduces a new principle for optimizing the comprehensive properties of Fe-based amorphous/nanocrystalline alloys.

关键词： Fe-based nanocrystalline alloys In-situ nano-crystallization Micro-alloying Soft magnetic property

Subnanometric bimetallic Pt-Pd clusters in zeolites for efficient hydrogen production and selective tandem hydrogenation of nitroarenes

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Science china Chemistry 2024年第9期67卷 2911-2917页

作者： Jiafu Li Tao Cai Yanran feng Xia {1. Ning Wang Qiming sun institute of Sustainable Energy and Resources College of Chemistry and Chemical EngineeringKey Laboratory of Shandong Provincial Universities for Functional Molecules and MaterialsQingdao UniversityQingdao 266071China Innovation Center for Chemical Sciences College of ChemistryChemical Engineering and Materials ScienceJiangsu Key Laboratory of Advanced Negative Carbon TechnologiesSoochow UniversitySuzhou 215123China

The solvolysis of ammonia borane(AB)and the hydrogenation of nitroarenes represent significant reactions for hydrogen generation and value-added chemical *** strategic engineering of the catalysts is imperative for surmounting obstacles associated with their stability and catalytic *** this work,subnanometric bimetallic Pt–Pd clusters were encapsulated within silicalite-1.S-1.zeolites through a ligand-protected in-situ hydrothermal synthesis *** synergetic effect of bimetallic composition and zeolite confinement markedly enhances the catalytic performance of representative Pt_(0.5)Pd_(0.5)@S-1.H catalyst,affording exceptional turnover frequency(TOF)values of 1.043 and 573 mol_(H_(2))mol_(metal)^(-1.min^(-1.for AB hydrolysis and methanolysis at ambient conditions,respectively,surpassing most of the state-of-the-art Pt-based *** and isotopic experiments reveal that the bimetallic catalytic system remarkably boosts the O-H cleavage of water,thereby facilitating the H_(2) production from AB ***,a conspicuous synergistic effect is demonstrated in the shape-selective tandem hydrogenation of nitroarenes,with the bimetallic catalyst facilitating both AB hydrolysis and nitroarene hydrogenation,giving a high TOF value of 1.260 h^(-1.under atmospheric *** study not only demonstrates the effectiveness of bimetallic nanocatalysts encapsulated in zeolites for hydrogen production from chemical hydrogen storage materials,but also paves the way for the design of catalysts with multifunctional active sites capable of synergistically promoting tandem catalytic processes.

关键词： subnanometer bimetallic cluster zeolite synergistic effect ammonia borane solvolysis selective tandem hydrogenation

Mathematical stencil and its application in finite difference approximation to the Poisson equation

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Science china Mathematics 2005年第10期48卷 1421-1429页

作者： feng Hui~1.ZHANG Baolin~(1.2) & {1. Yang~1.1. Department of Mathematics,Wuhan university,Wuhan 430072,china 2. Laboratory of Computational physics,institute of Applied physics and Computational Mathematics,Beijing 1.0088. china Department of Mathematics Wuhan University Wuhan China Laboratory of Computational physics Institute of Applied Physics and Computational Mathematics Beijing China

The concept of mathematical stencil and the strategy of stencil elimination for solving the finite difference equation is presented, and then a new type of the iteration algorithm is established for the Poisson equation. The new algorithm has not only the obvious property of parallelism, but also faster convergence rate than that of the classical Jacobi iteration. Numerical experiments show that the time for the new algorithm is less than that of Jacobi and Gauss-Seidel methods to obtain the same precision, and the computational velocity increases obviously when the new iterative method, instead of Jacobi method, is applied to polish operation in multi-grid method, furthermore, the polynomial acceleration method is still applicable to the new iterative method.

关键词： mathematical stencil, stencil elimination, Poisson equation, finite difference, iterative algorithm,parallelism.

Boosting zinc anode durability through synergistic inner Helmholtz plane and interfacial electric field regulation

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Science Bulletin 2024年第13期69卷 2025-2029页

作者： hao Tan Chao Meng Tong sun Xing-Long Wu Hong liu Jian-Jun Wang State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China MOE Key Laboratory for UV Light-Emitting Materials and Technology Department of PhysicsNortheast Normal UniversityChangchun 130024China Jinan institute of Quantum Technology Jinan BranchHefei National LaboratoryJinan 250101China Shenzhen Research institute Shandong UniversityShenzhen 518057China

As the need for energy storage devices escalates,aqueous zincion batteries(ZIBs)have risen as a promising alternative to the widely used Li-ion batteries,offering intrinsic safety,environmental compatibility,and cost advantages,positioning them as attractive energy storage systems for the future[1.2].However,challenges such as dendrite growth on Zn anodes,stemming from uneven electric fields on the surface and active water side reactions,compromise cycling stability and lifespan,posing significant hurdles for the practical application of ZIBs[3,4].To mitigate these issues,strategies like electrolyte optimization,artificial solid electrolyte interphase(SEI)layers,and current collector modifications have been proposed[5,6].Nevertheless,most long-cycle experiments are conducted at low current densities and deposition capacities,with high current density and capacity operations typically lasting less than 1.00 h[7].

关键词： electrolyte durability offering

A study of two-dimensional magnetic polaron

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Science china({1.,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： liu Tao1. ZHANG Huaihong1. {1. Mang1.2 & WANG Kelin1.3 1. School of Science, Southwest university of Science and Technology, Mianyang 621.1., china 2. Wuhan institute of physics and Mathematics, Chinese Academy of Sciences, Wuhan 430070, china 3. Department of Modern physics, university of Science and Technology of china, Hefei 230026, china School of Science Southwest University of Science and Technology Mianyang China Wuhan institute of {1. and Mathematics Chinese Academy of Sciences Wuhan China Department of Modern physics University of Science and Technology of China Hefei China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

A Wnt1.a-Notch signaling axis controls Hertwig’s epithelial root sheath cell behaviors during root furcation patterning

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International Journal of Oral Science 2024年第3期16卷 425-435页

作者： Kai sun Miao Yu Jiayu Wang Hu Z{1. {1.chen liu Hailan feng Yang liu Dong Han Department of Prosthodontics Peking University School and Hospital of Stomatology&National Center for Stomatology&National Clinical Research Center for Oral Diseases&National Engineering Research Center of Oral Biomaterials and Digital Medical DevicesBeijingChina Chinese institute for Brain Research BeijingChina

Human with bi-allelic WNT1.A mutations and epithelial Wnt1.a knockout mice present enlarged pulp chamber and apical displacement of the root furcation of multi-rooted teeth,known as taurodontism;thus,indicating the critical role of Wnt1.a in tooth root ***,the endogenous mechanism by which epithelial Wnt1.a regulates Hertwig’s epithelial root sheath(HERS)cellular behaviors and contributes to root furcation patterning remains *** this study,we found that HERS in the presumptive root furcating region failed to elongate at an appropriate horizontal level in K1.-Cre;Wnt1.a^(fl/fl)mice from post-natal day 0.5(PN0.5)to *** assays and immunofluorescent staining of cyclin D1.revealed significantly decreased proliferation activity of inner enamel epithelial(IEE)cells of HERS in K1.-Cre;Wnt1.a^(fl/fl)mice at PN2.5 and *** staining of E-Cadherin and acetyl-α-Tubulin demonstrated that the IEE cells of HERS tended to divide perpendicularly to the horizontal plane,which impaired the horizontal extension of HERS in the presumptive root furcating region of K1.-Cre;Wnt1.a^(fl/fl)***-seq and immunofluorescence showed that the expressions of Jag1.and Notch2 were downregulated in IEE cells of HERS in K1.-Cre;Wnt1.a^(fl/fl)***,after activation of Notch signaling in K1.-Cre;Wnt1.a^(fl/fl)molars by Notch2 adenovirus and kidney capsule grafts,the root furcation defect was partially *** together,our study demonstrates that an epithelial Wnt1.a-Notch signaling axis is crucial for modulating HERS cell proper proliferation and horizontal-oriented division during tooth root furcation morphogenesis.

关键词： Wnt1.a Notch impaired

Controllable synthesis of one-dimensional silicon nanostructures based on the dual effects of electro-deoxidation and the Kirkendall effect

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Nano Research 2024年第9期17卷 7814-7823页

作者： Jianxin Tu Shuo Yu Kui hao Le {1. Ruicheng Bai Fangzhou Zhang Aijun Li Hong liu institute of Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Department of Applied physics The Hong Kong Polytechnic UniversityKowloon 999077Hong KongChina Shaoxing {1. of technology Shanghai UniversityShanghai 200444China

In this study,we successfully synthesized silicon nanotubes(Si-NTs)and silicon nanowires(Si-NWs)in a controllable manner using a catalyst-and template-free method through the direct electrolysis of SiO_(2)in a molten CaCl_(2)-CaO system,while also proposing a novel formation mechanism for ***-NWs are formed through electro-deoxidation when the cell voltage is within the range of CaO decomposition voltage and SiO_(2)decomposition *** subsequently adjusting the voltage to a value between the decomposition potentials of CaCl_(2)and CaO,in-situ electro-deoxidation of CaO takes place on the surface of the synthesized Si-NWs,leading to the formation of a Ca *** formation of Ca-Si diffusion couple leads to the creation of vacancies within the Si-NWs,as the outward diffusion rate of Si exceeds the inward diffusion rate of *** differential diffusion rates between Si and Ca in a diffusion couple exhibit an analogy to the Kirkendall *** vacancies gradually accumulate and merge,forming large voids,which ultimately result in the formation of hollow *** a subsequent dealloying process,the removal of the embedded calcium leads to the formation of *** the application of a carbon coating,the Si-NTs@C composite showcases a high initial discharge capacity of 321. mAh·g^(-1.at 1.5 A·g^(-1.and exhibits exceptional long-term cycling stability,maintaining a capacity of 977 mAh·g^(-1.after 2000 cycles at 3.0 A·g^(-1..

关键词： silicon nanotubes silicon nanowires lithium-ion battery Kirkendall effect