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Mesoporous Carbon Nanofibers Loaded with Ordered PtFe Alloy Nanoparticles for Electrocatalytic Nitrate Reduction to Ammonia
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作者 XIE Meng LUO Wei QIU Pengpeng 《Journal of Donghua University(English Edition)》 CAS 2024年第4期365-376,共12页
Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we... Highly dispersed bimetallic alloy nanoparticle electrocatalysts have been demonstrated to exhibit exceptional performance in driving the nitrate reduction reaction(NO_(3)RR)to generate ammonia(NH_(3)).In this study,we prepared mesoporous carbon nanofibers(mCNFs)functionalized with ordered PtFe alloys(O-PtFe-mCNFs)by a composite micelle interface-induced co-assembly method using poly(ethylene oxide)-block-polystyrene(PEO-b-PS)as a template.When employed as electrocatalysts,O-PtFe-mCNFs exhibited superior electrocatalytic performance for the NO_(3RR)compared to the mCNFs functionalized with disordered PtFe alloys(D-PtFe-mCNFs).Notably,the NH_(3)production performance was particularly outstanding,with a maximum NH_(3)yield of up to 959.6μmol/(h·cm~2).Furthermore,the Faraday efficiency(FE)was even 88.0%at-0.4 V vs.reversible hydrogen electrode(RHE).This finding provides compelling evidence of the potential of ordered PtFe alloy catalysts for the electrocatalytic NO_(3)RR. 展开更多
关键词 ordered PtFe alloy mesoporous carbon nanofiber(mCNF) nitrate reduction reaction(NO3RR) ammonia(NH3)production reaction
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Wigner function of optical cumulant operator and its dissipation in thermo-entangled state representation
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作者 张科 李兰兰 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期205-210,共6页
To conveniently calculate the Wigner function of the optical cumulant operator and its dissipation evolution in a thermal environment, in this paper, the thermo-entangled state representation is introduced to derive t... To conveniently calculate the Wigner function of the optical cumulant operator and its dissipation evolution in a thermal environment, in this paper, the thermo-entangled state representation is introduced to derive the general evolution formula of the Wigner function, and its relation to Weyl correspondence is also discussed. The method of integration within the ordered product of operators is essential to our discussion. 展开更多
关键词 Wigner function optical cumulant operator dissipation evolution thermo-entangled state representation integration within ordered product of operators
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New light fields based on integration theory within the Weyl ordering product of operators
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作者 张科 李兰兰 +1 位作者 郭大伟 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期160-164,共5页
The development of quantum optics theory based on the method of integration within an ordered product of operators(IWOP)has greatly stimulated the study of quantum states in the light field,especially non-Gaussian sta... The development of quantum optics theory based on the method of integration within an ordered product of operators(IWOP)has greatly stimulated the study of quantum states in the light field,especially non-Gaussian states with various non-classical properties.In this paper,the two-mode squeezing operator is derived with integral theory within the Weyl ordering product of operators using a combinatorial field in which one mode is a chaotic field and the other mode is a vacuum field.The density operator of the new light field,its entanglement property and photon number distribution are analyzed.We also note that tracing a three-mode pure state can yield this new light field.These methods represent a theoretical approach to investigating new density operators of light fields. 展开更多
关键词 integration within an ordered product of operators two-mode squeezing operator Weyl ordering entanglement property
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THEORY AND APPLICATION OF FRACTIONAL STEP CHARACTERISTIC FINITE DIFFERENCE METHOD IN NUMERICAL SIMULATION OF SECOND ORDER ENHANCED OIL PRODUCTION 被引量:1
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作者 袁益让 程爱杰 +1 位作者 羊丹平 李长峰 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1547-1565,共19页
A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced (chemical) oil production in porous media.... A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced (chemical) oil production in porous media. Some techniques, such as the calculus of variations, energy analysis method, commutativity of the products of difference operators, decomposition of high-order difference operators and the theory of a priori estimates are introduced and an optimal order error estimates in l^2 norm is derived. This method has been applied successfully to the numerical simulation of enhanced oil production in actual oilfields, and the simulation results ate quite interesting and satisfactory. 展开更多
关键词 enhanced (chemical) oil production three-dimensional porous coupled system second-order implicit characteristic fractional step differences optimal order l^2 estimate application in actual oilfields
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The Allocation of Production orders to offshore Plants in the Clothing Industry: Part 2-Prototype System Supporting Order Allocation Decisions
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作者 梁润新 梁春森 +1 位作者 张文俊 蒙嘉亮 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期81-85,共5页
This part demonstrates a prototype system which has been constructed to enable the allocation of orders of different product types to different manufacturing locations . ’ What - if’ experiments using this system sh... This part demonstrates a prototype system which has been constructed to enable the allocation of orders of different product types to different manufacturing locations . ’ What - if’ experiments using this system show that different allocation rules would provide different outcomes in terms of the number of unallocated orders. A high number of unallocated orders will have a direct Impact on workload. Further research effort is necessary to channel into the exercbe of production order allocation with particular reference to allocation rules. 展开更多
关键词 production order aLLOCaTION production planning ofFSHORE sourcing.
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The Allocation of Production Orders to Offshore Plants in the Clothing Industry:Part1-Model Conceptualisation
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作者 梁润新 梁春森 +1 位作者 张文俊 蒙嘉亮 《Journal of China Textile University(English Edition)》 EI CAS 1998年第2期77-81,共5页
As a rough cut planning exercise,production order allo-cation for offshore manu facturing sites in the clothingindustry has received little attention as does other typesof planning like production planning.This paper ... As a rough cut planning exercise,production order allo-cation for offshore manu facturing sites in the clothingindustry has received little attention as does other typesof planning like production planning.This paper outlinesan investigation into the exercise of production order al-location in the clothing industry.We have identified thatpractitioners involving in this exercise are not unanimousin the selection of offshore sites.Part 1 presents thebackground,objectives,process and conceptual model ofproduction order allocation. 展开更多
关键词 production order aLLOCaTION production plan-ning ofFSHORE sourcing.
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Application of first order rate kinetics to explain changes in bloom toxicity——the importance of understanding cell toxin quotas 被引量:2
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作者 Philip T.ORR Anusuya WILLIS Michele A.BURFORD 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第4期1063-1074,共12页
Cyanobacteria are oxygenic photosynthetic Gram-negative bacteria that can form potentially toxic blooms in eutrophic and slow flowing aquatic ecosystems. Bloom toxicity varies spatially and temporally, but understandi... Cyanobacteria are oxygenic photosynthetic Gram-negative bacteria that can form potentially toxic blooms in eutrophic and slow flowing aquatic ecosystems. Bloom toxicity varies spatially and temporally, but understanding the mechanisms that drive these changes remains largely a mystery. Changes in bloom toxicity may result from changes in intracellular toxin pool sizes of cyanotoxins with differing molecular toxicities, and/or from changes in the cell concentrations of toxic and non-toxic cyanobacterial species or strains within bloom populations. We show here how first-order rate kinetics at the cellular level can be used to explain how environmental conditions drive changes in bloom toxicity at the ecological level. First order rate constants can be calculated for changes in cell concentration( μ_c : specific cell division rate) or the volumetric biomass concentration( μ_g : specific growth rate) between short time intervals throughout the cell cycle. Similar first order rate constants can be calculated for changes in nett volumetric cyanotoxin concentration( μ_(tox) : specific cyanotoxin production rate) over similar time intervals. How μ_c(or μ_g) covaries with μ tox over the cell cycle shows conclusively when cyanotoxins are being produced and metabolised, and how the toxicity of cells change in response to environment stressors. When μ_(tox)/μ_c >1, cyanotoxin cell quotas increase and individual cells become more toxic because the nett cyanotoxin production rate is higher than the cell division rate. When μ_(tox)/μ_c =1, cell cyanotoxin quotas remains fixed because the nett cyanotoxin production rate matches the cell division rate. When μ_(tox)/μ_c <1, the cyanotoxin cell quota decreases because either the nett cyanotoxin production rate is lower than the cell division rate, or metabolic breakdown and/or secretion of cyanotoxins is occurring. These fundamental equations describe cyanotoxin metabolism dynamics at the cellular level and provide the necessary physiological background to understand how environmental stressors drive changes in bloom toxicity. 展开更多
关键词 cyanotoxin production dynamics first order rate kinetics CYaNOBaCTERIa
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Unifying the theory of integration within normal-,Weyl- and antinormal-ordering of operators and the s-ordered operator expansion formula of density operators 被引量:2
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作者 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期41-47,共7页
By introducing the s-parameterized generalized Wigner operator into phase-space quantum mechanics we invent the technique of integration within s-ordered product of operators (which considers normally ordered, antino... By introducing the s-parameterized generalized Wigner operator into phase-space quantum mechanics we invent the technique of integration within s-ordered product of operators (which considers normally ordered, antinormally ordered and Weyl ordered product of operators as its special cases). The s-ordered operator expansion (denoted by s…s ) formula of density operators is derived, which isρ=2/1-s∫d^2β/π〈-β|ρ|β〉sexp{2/s-1(s|β|^2-β*α+βa-αα)}s The s-parameterized quantization scheme is thus completely established. 展开更多
关键词 s-parameterized generalized Wigner operator technique of integration within s-ordered product of operators s-ordered operator expansion formula s-parameterized quantization scheme
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Ordered product expansions of operators (AB)^±m with arbitrary positive integer
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作者 Shi-Min Xu Yu-Shan Li +2 位作者 Xing-Lei Xu Lei Wang Ji-Suo Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期154-160,共7页
We arrange quantum mechanical operators ■ in their normally ordered product forms by using Touchard polynomials.Moreover,we derive the anti-normally ordered forms of ■ by using special functions as well as Stirling-... We arrange quantum mechanical operators ■ in their normally ordered product forms by using Touchard polynomials.Moreover,we derive the anti-normally ordered forms of ■ by using special functions as well as Stirling-like numbers together with the general mutual transformation rule between normal and anti-normal orderings of operators.Further,the Q-and P-ordered forms of(QP)±m are also obtained by using an analogy method. 展开更多
关键词 Fock space new polynomial ordered product analogy method
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Tree Automata for Extracting Consensus from Partial Replicas of a Structured Document
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作者 Maurice Tchoupé Tchendji Milliam M. Zekeng Ndadji 《Journal of Software Engineering and Applications》 2017年第5期432-456,共25页
In an asynchronous cooperative editing workflow of a structured document, each of the co-authors receives in the different phases of the editing process, a copy of the document to insert its contribution. For confiden... In an asynchronous cooperative editing workflow of a structured document, each of the co-authors receives in the different phases of the editing process, a copy of the document to insert its contribution. For confidentiality reasons, this copy may be only a partial replica containing only parts of the (global) document which are of demonstrated interest for the considered co-author. Note that some parts may be a demonstrated interest over a co-author;they will therefore be accessible concurrently. When it’s synchronization time (e.g. at the end of an asynchronous editing phase of the process), we want to merge all contributions of all authors in a single document. Due to the asynchronism of edition and to the potential existence of the document parts offering concurrent access, conflicts may arise and make partial replicas unmergeable in their entirety: they are inconsistent, meaning that they contain conflictual parts. The purpose of this paper is to propose a merging approach said by consensus of such partial replicas using tree automata. Specifically, from the partial replicas updates, we build a tree automaton that accepts exactly the consensus documents. These documents are the maximum prefixes containing no conflict of partial replicas merged. 展开更多
关键词 Structured documents WORKFLOW of Cooperative Edition MERGING PaRTIaL Replicas CONFLICT CONSENSUS Tree aUTOMaTa aUTOMaTa Product Lazy Evaluation
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Theory and application of numerical simulation method of capillary force enhanced oil production
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作者 Yirang YUAN Aijie CHENG +2 位作者 Danping YANG Changfeng LI Yunxin LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第3期379-400,共22页
A kind of second-order implicit upwind fractional step finite difference methods are presented for the numerical simulation of coupled systems for enhanced (chemical) oil production with capillary force in the porou... A kind of second-order implicit upwind fractional step finite difference methods are presented for the numerical simulation of coupled systems for enhanced (chemical) oil production with capillary force in the porous media. Some techniques, e.g., the calculus of variations, the energy analysis method, the commutativity of the products of difference operators, the decomposition of high-order difference operators, and the theory of a priori estimate, are introduced. An optimal order error estimate in the l2 norm is derived. The method is successfully used in the numerical simulation of the enhanced oil production in actual oilfields. The simulation results are satisfactory and interesting. 展开更多
关键词 enhanced (chemical) oil production system on consideration ference optimal order l2 capillary force second-order three-dimensional porous coupled implicit upwind fractional step difestimate application in actual oilfield
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REVERSE ORDER LAW FOR GROUP INVERSE OF PRODUCT OF MATRICES ON SKEW FIELDS
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作者 Liu Yu (Dept.of Math.,Hulan Teacher College,Hulan 150500,PRC)Cao Chongguang(Dept.of Math.,Heilongjiang University,Harbin 150080,PRC) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期38-39,共2页
Let K<sup>n×n</sup> be the set of all n×n matrices and K<sub>r</sub><sup>n×n</sup> the set {A∈K<sup>n×n</sup>|rankA=r} on askew field K. Zhuang [1] ... Let K<sup>n×n</sup> be the set of all n×n matrices and K<sub>r</sub><sup>n×n</sup> the set {A∈K<sup>n×n</sup>|rankA=r} on askew field K. Zhuang [1] denotes by A<sup>#</sup> the group inverse of A∈K<sup>n×n</sup> which is the solu-tion of the euqations:AXA=A, XAX=X, AX=AX. 展开更多
关键词 MaTH RI RD REVERSE order LaW FOR GROUP INVERSE of PRODUCT of MaTRICES ON SKEW FIELDS OI aB
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Representation of residual stress symbol in the technical product documentation
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作者 Li Peilu Xu Chunguang +2 位作者 Song Wenyuan Li Shuangyi Ma Pengzhi 《China Standardization》 2021年第3期58-64,共7页
A representation of residual stress graphic symbols in technical product documents is studied.The residual stress state of the product can be annotated in the technical product documents such as design drawings,proces... A representation of residual stress graphic symbols in technical product documents is studied.The residual stress state of the product can be annotated in the technical product documents such as design drawings,process documents,test reports,papers and monographs.The composition of residual stress and the design of basic symbols,measurement method symbols,relief method symbols and state symbols of residual stress,and the representation of annotation for residual stress in documents are introduced.Residual stress symbol can be used in the design,manufacturing,inspection and service for the residual stress state requirements of the products in the mechanical manufacturing industry,as well as in light industry,daily necessities and other related industries. 展开更多
关键词 technical product documentation residual stress SYMBOL aNNOTaTION stress measurement stress relief
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A General Method of Researching the N-Ordered Fixed Point on a Metric Space with a Graph
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作者 Xiaonan Liang Shiyun Wang 《Journal of Applied Mathematics and Physics》 2020年第12期2846-2860,共15页
In this paper, we propose a new perspective to discuss the N-order fixed point theory of set-valued and single-valued mappings. There are two aspects in our work: we first define a product metric space with a graph fo... In this paper, we propose a new perspective to discuss the N-order fixed point theory of set-valued and single-valued mappings. There are two aspects in our work: we first define a product metric space with a graph for the single-valued mapping whose conversion makes the results and proofs concise and straightforward, and then we propose an <em>SG</em>-contraction definition for set-valued mapping which is more general than some recent contraction’s definition. The results obtained in this paper extend and unify some recent results of other authors. Our method to discuss the N-order fixed point unifies <em>N</em>-order fixed point theory of set-valued and single-valued mappings. 展开更多
关键词 N-order Fixed Point Product Metric Space Endowed with a Graph Set-Valued Mapping SG-Contraction
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Wigner function and density operator of the photon-subtracted squeezed thermal state 被引量:1
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作者 胡利云 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期4657-4661,共5页
By using the technique of integration within an ordered product of operators, the normal ordered density operator of the photon-subtracted squeezed thermal state (PSSTS) is derived. Then the corresponding Wigner fun... By using the technique of integration within an ordered product of operators, the normal ordered density operator of the photon-subtracted squeezed thermal state (PSSTS) is derived. Then the corresponding Wigner function is presented by using the coherent state representation of the Wigner operator. The nonclassical properties of the PSSTS are discussed based on the negativity of the Wigner function. 展开更多
关键词 Wigner function photon-subtraction squeezed thermal state integration with in an ordered product technique
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New decomposition of the Fresnel operator corresponding to the optical transformation in ABCD-systems 被引量:1
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作者 杜建明 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期166-170,共5页
By virtue of the coherent state representation of the newly introduced Fresnel operator and its group product property we obtain new decomposition of the Fresnel operator as the product of the quadratic phase operator... By virtue of the coherent state representation of the newly introduced Fresnel operator and its group product property we obtain new decomposition of the Fresnel operator as the product of the quadratic phase operator, the squeezing operator, and the fractional Fourier transformation operator, which in turn sheds light on the matrix optics design of ABCD-systems The new decomposition for the two-mode Fresnel operator is also obtained by the use of entangled state representation. 展开更多
关键词 Fresnel operator integration within an ordered product technique optical transformation
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The squeezing entangled state of two particles with unequal mass 被引量:1
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作者 杨阳 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期143-145,共3页
For two unequal-mass particles,we construct the entangled state representation and then derive the corresponding squeezing operator.This squeezing operator has a natural realization in the entangled state representati... For two unequal-mass particles,we construct the entangled state representation and then derive the corresponding squeezing operator.This squeezing operator has a natural realization in the entangled state representation,which exhibits the intrinsic relation between squeezing and quantum entanglement.This squeezing operator involves both two-mode squeezing and the direct product of two single-mode squeezings.The maximum squeezing occurs when the two particles possess equal mass.When the two particles' mass difference becomes large,the component of the two single-mode squeezings becomes dominant. 展开更多
关键词 squeezing operator integration within an ordered product(IWOP) technique entangled state representation
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New generating function formulae of even- and odd-Hermite polynomials obtained and applied in the context of quantum optics 被引量:1
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作者 范洪义 展德会 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第6期18-22,共5页
By combining the operator Hermite polynomial method and the technique of integration within an ordered product of operators, for the first time we derive the generating function of even- and odd-Hermite polynomials wh... By combining the operator Hermite polynomial method and the technique of integration within an ordered product of operators, for the first time we derive the generating function of even- and odd-Hermite polynomials which will be useful in constructing new optical field states. We then show that the squeezed state and photon-added squeezed state can be expressed by even- and odd-Hermite polynomials. 展开更多
关键词 generating function even- and odd-Hermite polynomials Hermite polynomial method techniqueof integral within an ordered product of operators
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Some new generating function formulae of the two-variable Hermite polynomials and their application in quantum optics 被引量:1
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作者 展德会 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期30-33,共4页
We derive some new generating function formulae of the two-variable Hermite polynomials, such as ∞∑n=0tm/m!Hn,2m(x),∞∑n=0sntm/n!m!H2n,2m(x,y),and ∞∑n=0sntm/n!m!H2n+l,2m+k(x,y).We employ the operator Herm... We derive some new generating function formulae of the two-variable Hermite polynomials, such as ∞∑n=0tm/m!Hn,2m(x),∞∑n=0sntm/n!m!H2n,2m(x,y),and ∞∑n=0sntm/n!m!H2n+l,2m+k(x,y).We employ the operator Hermite polynomial method and the technique of integration within an ordered product of operators to solve these problems, which will be useful in constructing new optical field states. 展开更多
关键词 generating function two-variable Hermite polynomials Hermite polynomial method technique of integral within an ordered product of operators
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A new kind of special function and its application 被引量:1
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作者 范洪义 万志龙 +1 位作者 吴泽 张鹏飞 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期41-44,共4页
By virtue of the operator Hermite polynomial method and the technique of integration within the ordered product of operators we derive a new kind of special function, which is closely related to one- and two-variable ... By virtue of the operator Hermite polynomial method and the technique of integration within the ordered product of operators we derive a new kind of special function, which is closely related to one- and two-variable Hermite polynomials.Its application in deriving the normalization for some quantum optical states is presented. 展开更多
关键词 new special function new operator identities and integration formulas Hermite-polynomial exci-tation state integration within ordered product of operators (IWOP) method
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