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鱼油n-3 PUFA富集、稳态化技术及生物活性研究进展
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作者 刘书源 郭明珠 +2 位作者 马爱进 桑亚新 孙纪录 《中国食品学报》 EI CAS CSCD 北大核心 2024年第2期467-478,共12页
鱼油富含人体所需的多不饱和脂肪酸,在科研与应用领域具有广泛价值。本文重点围绕其n-3 PUFA富集工艺、稳态化技术及生物活性进行综述,阐述不同方法的优、缺点,分析工业化生产的可行性,展望未来鱼油加工领域的发展趋势,旨在为鱼油类资... 鱼油富含人体所需的多不饱和脂肪酸,在科研与应用领域具有广泛价值。本文重点围绕其n-3 PUFA富集工艺、稳态化技术及生物活性进行综述,阐述不同方法的优、缺点,分析工业化生产的可行性,展望未来鱼油加工领域的发展趋势,旨在为鱼油类资源的合理、健康、可持续发展提供理论依据。 展开更多
关键词 鱼油 富集工艺 稳态化 n-3 PUFA
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Mon(n=2-13)和MonC(n=1-12)团簇的几何结构和电子结构
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作者 杨文辉 相悦 +1 位作者 陈轩 段海明 《原子与分子物理学报》 北大核心 2024年第6期52-59,共8页
结合遗传算法和CALYPSO软件,采用密度泛函理论,对Mon(n=2-13)及MonC(n=1-12)团簇基态的几何结构与电子结构展开详细研究.通过计算其基态结构的平均键长、平均结合能、二阶差分能、分裂能和前线轨道能级,对基态结构的稳定性随总原子数变... 结合遗传算法和CALYPSO软件,采用密度泛函理论,对Mon(n=2-13)及MonC(n=1-12)团簇基态的几何结构与电子结构展开详细研究.通过计算其基态结构的平均键长、平均结合能、二阶差分能、分裂能和前线轨道能级,对基态结构的稳定性随总原子数变化的关系展开了研究.计算结果表明,Mon团簇基态结构的稳定性可通过掺杂单个C原子而提高.综合团簇的二阶差分能、分裂能可知,n=6,9时Mon团簇的稳定性较高,n=4,7,10时MonC团簇的稳定性较高. 展开更多
关键词 密度泛函理论 Mon团簇 MonC团簇 基态结构 电子性质
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N量子比特系统的纠缠判据
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作者 谭维翰 赵超樱 郭奇志 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第1期9-18,共10页
在前文(2019 Int. J.Mod.Phys.B 33 1950197;2020 Int.J.Mod.Phys.B 34 2050022)中,我们提出了一种判断2量子比特系统纠缠的方法,2量子比特系统可分的充分必要条件是相关系数为正且主密度矩阵可分,否则系统纠缠.在本文中,通过数值计算... 在前文(2019 Int. J.Mod.Phys.B 33 1950197;2020 Int.J.Mod.Phys.B 34 2050022)中,我们提出了一种判断2量子比特系统纠缠的方法,2量子比特系统可分的充分必要条件是相关系数为正且主密度矩阵可分,否则系统纠缠.在本文中,通过数值计算与讨论,先将2量子比特系统纠缠判据的方法推广到3量子比特系统中去;接着,继续将3量子比特系统推广到N量子比特系统中去.这是一个复杂而有趣的问题. 展开更多
关键词 玻恩几率密度 n量子比特系统 纠缠态
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融合Graph state LSTM与注意力机制的跨句多元关系抽取
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作者 衡红军 姚若男 《计算机应用与软件》 北大核心 2023年第8期214-220,290,共8页
已有的跨句多元关系抽取工作将输入文本表示为集成句内和句间依赖关系的复杂文档图,但图中包含的噪声信息会影响关系抽取的效果。针对这种情况,该文利用Graph state LSTM获得上下文信息,再分别利用词级注意力机制或位置感知的注意力机制... 已有的跨句多元关系抽取工作将输入文本表示为集成句内和句间依赖关系的复杂文档图,但图中包含的噪声信息会影响关系抽取的效果。针对这种情况,该文利用Graph state LSTM获得上下文信息,再分别利用词级注意力机制或位置感知的注意力机制,自动聚焦在对关系抽取起到决定性作用的关键词上,降低噪声信息的影响。并且比较了两种注意力机制对使用Graph state LSTM进行关系抽取的影响。通过在一个重要的精确医学数据集上进行实验,验证了该文所提出模型的有效性。 展开更多
关键词 跨句多元关系抽取 注意力机制 Graph state LSTM
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Probabilistic Teleportation of n-Particle State via n Pairs of Entangled Particles 被引量:8
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作者 CAOMin ZHUShi-Qun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1期69-72,共4页
The teleportation of an arbitrary n-particle state is proposed when n pairs of entangled particles are utilized as quantum channels. It can be successfully realized with a certain probability which is determined by th... The teleportation of an arbitrary n-particle state is proposed when n pairs of entangled particles are utilized as quantum channels. It can be successfully realized with a certain probability which is determined by the smallest coefficients of n entangled pairs. Using a Latin square of order 2n, explicit expressions of two unitary operations corresponding to different Bell-basis measurements performed by Alice can be obtained at the end of Bob. 展开更多
关键词 probabilistic teleportation n-particle state latin square n pairs ofentangled particles
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Atomic N00N state generation in distant cavities by virtual excitations 被引量:1
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作者 杨榕灿 李刚 +1 位作者 李杰 张天才 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期12-18,共7页
A general scheme of generating NOON states of virtually-excited 2N atoms is proposed. The two cavities are fibre-connected with N atoms in each cavity. Although we focus on the case of N = 2, the system can be extende... A general scheme of generating NOON states of virtually-excited 2N atoms is proposed. The two cavities are fibre-connected with N atoms in each cavity. Although we focus on the case of N = 2, the system can be extended to a few atoms with N 〉2. It is found that all 2N atoms can be entangled in the form of NOON states if the atoms in the first cavity are initially in the excited states and atoms in the second cavity are all in the ground states. The feasibility of the scheme is carefully discussed, it shows that the NOON state with a few atoms can be generated with good fidelity and the scheme is feasible in experiment. 展开更多
关键词 n00n states optical cavity optical fibre virtual excitations
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Teleportation of an Arbitrary Multipartite GHZ-Class State by One EPR Pair 被引量:3
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作者 王雅红 于长水 宋鹤山 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第12期3142-3144,共3页
We present a scheme for perfectly teleporting an arbitrary and unknown N-particle GHZ-class state from a sender to a receiver. We just need one quantum channel composed of two or three particles in the maximally entan... We present a scheme for perfectly teleporting an arbitrary and unknown N-particle GHZ-class state from a sender to a receiver. We just need one quantum channel composed of two or three particles in the maximally entangled state. The sender performs one Bell-state measurement on two of her particles and N - 1 Hadamard operations and N - 1 yon Neumann measurements on the rest N - 1 particles. The receiver adopts one corresponding unitary transformation on his particles shared with the sender. After that, the receiver can obtain the original N-particle GHZ-class state by introducing N - 1 ancillary particles and carrying out N - 1 controlled-NOT operations. We also generalize the scheme to the case of controlled teleportation. 展开更多
关键词 n-PARTICLE state PROBABILISTIC TELEPORTATIOn 2-PARTICLE state EnTAnGLEDstate QUAnTUM state CHAnnELS
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A new representation and probabilistic teleportation of an arbitrary and unknown N-particle state 被引量:6
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作者 董莉 修晓明 高亚军 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2835-2839,共5页
A new representation of an arbitrary and unknown N-particle state is presented at first. As an application, a scheme for teleporting an arbitrary and unknown N-particle state is proposed when N pairs of two-particle n... A new representation of an arbitrary and unknown N-particle state is presented at first. As an application, a scheme for teleporting an arbitrary and unknown N-particle state is proposed when N pairs of two-particle non- maximally entangled states are utilized as quantum channels. After Alice (sender) makes Bell-state measurement on her particles, Bob (recipient) introduces an auxiliary particle and carries out appropriate unitary transformation on his particle and the auxiliary particle depending on classical information from Alice. Then, von Neumann measurement that confirms whether the teleportation succeeds or not is performed by Bob on the auxiliary particle. In order to complete the teleportation, another N-1 times operations need to be performed which are similar to the above ones. It can be successfully realized with a certain probability which is determined by the product of the smaller coefficients of non-maximally entangled pairs. All possible unitary transformations are given in detail. 展开更多
关键词 arbitrary and unknown n-particle state probabilistic teleportation entanglement
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An Efficient Solid-State Synthesis of N-Aryl-2-phenyldiazenecarboxamides 被引量:2
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作者 Jian Ping LI Qian Fu LUO +2 位作者 Yi Yang SHEN Yu Lu WANG Hong WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第2期107-108,共2页
A new and ancient solid-state reaction using K3Fe(CN)(6)/KOII to oxidize diaryl semicarbazides for preparing azo compounds has been reported. Nine N-aryl-2-phenyl-diazenecarboxamides have been synthesized in excellent... A new and ancient solid-state reaction using K3Fe(CN)(6)/KOII to oxidize diaryl semicarbazides for preparing azo compounds has been reported. Nine N-aryl-2-phenyl-diazenecarboxamides have been synthesized in excellent yields with simple instrument. 展开更多
关键词 Solid-state synthesis diaryl semicarbazide n-Aryl-2-phenyldiazenecarboxamide
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STATE TRANSFORMATION PROCESSES FOR FREE-FLOATING THREE-LINK PLANAR ROBOTS 被引量:1
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作者 XuMingtao XuYangsheng JamesK.Mills 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第2期166-169,共4页
The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF trans... The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF transformation processes as an alternative to them-DOF transformation process. Two static state transformation processes are studied in detail.First, a single-DOF transformation process is established using a newly defined concept, referred toas transformation planning, and the definite integral of conservation of angular momentum. Second,the governing equation of the single-DOF transformation process is established using the dynamicequations of motion of the robot. This allows the joint torques to be computed to effect the statetransformation. Finally, an extension of the single-DOF transformation process is proposed to extendthe application of this proposed transformation methodology to create a transformation net whichallows the reconfiguration of a robot from one state to many other possible states. 展开更多
关键词 Planar robot Static state Single-DOF transformation process n-elementtransformation net
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Exact bound state solutions of the Klein-Gordon particle in Hulthn potential
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作者 张民仓 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3214-3216,共3页
In this paper, the Klein-Gordon equation with the spherical symmetric Hulthén potential is turned into a hypergeometric equation and is solved in the framework of function analysis exactly. The corresponding boun... In this paper, the Klein-Gordon equation with the spherical symmetric Hulthén potential is turned into a hypergeometric equation and is solved in the framework of function analysis exactly. The corresponding bound state solutions are expressed in terms of the hypergeometric function, and the energy spectrum of the bound states is obtained as a solution to a given equation by boundary constraints. 展开更多
关键词 Hulthén potential Klein-Gordon equation bound state hypergeometric function
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VALENCE STATE OF C AtOMS AND σ_t-η_n SEPARABILITY OF MOLECULAR ORBITALS IN THE (BUCKMINSTER)FULLERENE C_(50)
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作者 Ji Min YAN Xue Qi YI 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第11期883-886,共4页
The valence state of C atoms and the structure of molecular orbitals of the (Buckminster)Fullerene C_(60)have been demonstrated. It has been shown that when a motion-coordinate system is adopted, in which the coordina... The valence state of C atoms and the structure of molecular orbitals of the (Buckminster)Fullerene C_(60)have been demonstrated. It has been shown that when a motion-coordinate system is adopted, in which the coordinate origin is at every C atom, the z axis is in the direction of the normal and the (x,y) axes are in the direction of tangents of C_(60)'s spherical surface, 240 valence atomic orbitals of C_(60) can be divided into two groups. All (P_x, P_y)atomic orbitals named as Pt ones and all the other P_z atomic orbitals named as p. ones, That is to say that if we name the molecular orbital linearly combined of P_t atomic orbitals as σ_t and the molecular orbital linearly combined of P_n atomic orbitals as π_n, the 240 valence molecular orbitals are of the property of σ_t-π_n separability. It has also been shown that the frontier and nearby frontier molecular orbitals are π_n ones, and therefore the essential physical and chemical properties of C_(60) are determined by its π_n molecular orbitals. 展开更多
关键词 BUCKMInSTER)FULLEREnE C VALEnCE state OF C AtOMS AnD n SEPARABILITY OF MOLECULAR ORBITALS In THE
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Solid-liquid state pressure bonding of Si_3N_4 ceramics with aluminum based alloys and its mechanism
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作者 邹贵生 吴爱萍 任家烈 《中国有色金属学会会刊:英文版》 CSCD 2001年第2期177-182,共5页
Solid liquid state pressure bonding of Si 3N 4 ceramics with aluminum based alloys, which contain a small amount of intermetallic compounds Al 3Ti or Al 3Zr, was investigated. With this new method, the heat resistant ... Solid liquid state pressure bonding of Si 3N 4 ceramics with aluminum based alloys, which contain a small amount of intermetallic compounds Al 3Ti or Al 3Zr, was investigated. With this new method, the heat resistant properties of the bonding zone metal are improved, and the joints’ strengths at high temperature is increased. The joints’ shear strength at room temperature and at 600 ℃ reach 126~133 MPa and 32~34 MPa, respectively, with suitable bonding pressure. The reaction between aluminum and Si 3N 4 ceramics, which produces Al Si N O type compounds is the dominant interfacial reaction, while the reactions between the second active element Ti or Zr in the aluminum based alloys and Si 3N 4 ceramics also occur to some extend. [ 展开更多
关键词 solid liquid state pressure bonding Si 3n 4 ceramics intermetallic compounds high temperature properties
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MRSDCI STUDIES OF LOW-LYING ELECTRONIC STATES OF THE N_2F^+ MOLECULE
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作者 Zheng Li CAI He Ming XIAO Department of Chemistry,East China Institute of Technology,Nanjing 210014 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期651-652,共2页
Ab initio electronic structure calculations are reported for low-lying electronic states,X ~1Σ^+and A ~1Π of the N_2F^+ molecule.Geometric parameters for the ground state X ~1Σ^+ are predicted by means of mul- tire... Ab initio electronic structure calculations are reported for low-lying electronic states,X ~1Σ^+and A ~1Π of the N_2F^+ molecule.Geometric parameters for the ground state X ~1Σ^+ are predicted by means of mul- tireference single and double excitation configuration interaction(MRSDCI)calculations with a double zeta plus polarization(DZ+P)basis set.Vertical excitation energy for these two electronic states is determined using MRSDCI/DZ+P calculations at the ground state equilibrium geometry.The oscillator strength for the X^1Σ+→ A ~1Π transition and the radiative lifetime for the A^1Π state are calculated based on the MRSDCI wavefunc- tions. 展开更多
关键词 MRSDCI STUDIES OF LOW-LYInG ELECTROnIC stateS OF THE n2F MOLECULE
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Rheological behavior of Al_2O_ 3n/Al_μ composite in pseudo-semi-solid state
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作者 程远胜 杜之明 罗守靖 《中国有色金属学会会刊:英文版》 CSCD 2005年第S2期142-146,共5页
A new technology for ceramics matrix composites-ceramics matrix composite thixoforming in pseudo-semi-solid state based on semi-solid metal process and powder metallurgy technology were proposed. The rheological behav... A new technology for ceramics matrix composites-ceramics matrix composite thixoforming in pseudo-semi-solid state based on semi-solid metal process and powder metallurgy technology were proposed. The rheological behavior of Al2O 3n/Alμ composite was studied by isothermal compression in pseudo-semi-solid state. The variation rules of the true stress-true strain, rheological behavior and the influencing factors were also analyzed. The results show that the flow stress decreases evidently with the increasing pseudo-semi-solid temperature, and that the trend of the true stress-true strain curve of the composite in pseudo-semi-solid state can be divided into four stages: increase, decline, re-increase and re-decline. 展开更多
关键词 Al2O 3n/Alμ COMPOSITE pseudo-semi-solid state ISOTHERMAL compression RHEOLOGICAL behavior
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Generation of entangled coherent states through cavity-assisted interaction
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作者 陈晓东 顾永建 +2 位作者 梁鸿辉 倪彬彬 林秀敏 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期77-80,共4页
We propose schemes to generate an n-coherent-pulse GHZ state and a cluster state via the interaction between n coherent pulses and a two-sided cavity. In these schemes, a strong coupling condition is not needed, which... We propose schemes to generate an n-coherent-pulse GHZ state and a cluster state via the interaction between n coherent pulses and a two-sided cavity. In these schemes, a strong coupling condition is not needed, which makes the protocols possibly able to be implemented based on the current experiment technology. 展开更多
关键词 n-coherent-pulse GHZ state n-coherent-pulse cluster state two-sided cavities
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A Single Photon Produces General W State of N 0ubits and Its Application
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作者 MEI Di LI Chong SONG He-Shan Department of Physics,Dalian University of Technology,Dalian 116023,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期75-78,共4页
Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only relate... Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only related to their coefficients and we successfully apply the general N-qubit W state to quantum state transferand quantum state prepare like that in two-qubit system. 展开更多
关键词 n-qubit W state COnCURREnCE quantum state transfer
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Scheme for probabilistic remotely preparing a multi-particle entangled GHZ state
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作者 马鹏程 詹佑邦 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期445-450,共6页
This paper presents a scheme for probabilistic remote preparation of a three-particle entangled Greenberger-Horne-Zeilinger (GHZ) state via three-particle orthonormal basis projective measurement, and then directly ... This paper presents a scheme for probabilistic remote preparation of a three-particle entangled Greenberger-Horne-Zeilinger (GHZ) state via three-particle orthonormal basis projective measurement, and then directly generalize the scheme to multi-particle case. It is shown that by using N pairs of bipartite non-maximally entangled states as the quantum channel and N-particle orthonormal basis projective measurement, the multi-particle remote preparation can be successfully realized with a certain probability. 展开更多
关键词 n-particle entangled GHZ state probabilistic remote state preparation n-particle projective measurement unitary transformation
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Generation of GHZ state and cluster state with atomic ensembles via the dipole-blockade mechanism
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作者 倪彬彬 顾永建 +3 位作者 陈晓东 梁鸿辉 林秀 林秀敏 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期168-172,共5页
This paper proposes scalable schemes to generate the Greenberger-Horne-Zeilinger (GHZ) state and the cluster state with atomic ensembles via the dipole blockade mechanism on an atom chip, where the qubit is not carr... This paper proposes scalable schemes to generate the Greenberger-Horne-Zeilinger (GHZ) state and the cluster state with atomic ensembles via the dipole blockade mechanism on an atom chip, where the qubit is not carried by a single atom but an atomic ensemble. In the protocols, multiqubit entangled states are determinately prepared. Needlessness for single-photon source further decreases the complexity of the experiment. Based on the present laboratory technique, the schemes may be realized. The achieved results reveal a prospect for large-scale quantum communication and quantum computation. 展开更多
关键词 Jipole-blockade mechanism n-qubit GHZ state n-qubit cluster
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Approximate Bound State Solutions for Certain Molecular Potentials
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作者 Mahmoud Farout Mohammed Yasin Sameer M. Ikhdair 《Journal of Applied Mathematics and Physics》 2021年第4期736-750,共15页
We present solutions of the Schrodinger equation with superposition of Manning-Rosen plus inversely Mobius square plus quadratic Yukawa potentials using parametric Nikiforov Uvarov method along with an approximation t... We present solutions of the Schrodinger equation with superposition of Manning-Rosen plus inversely Mobius square plus quadratic Yukawa potentials using parametric Nikiforov Uvarov method along with an approximation to the centrifugal term. The bound state energy eigenvalues for any angular momentum quantum number <em>l</em> and the corresponding un-normalized wave functions are calculated. The mixed potential which in some particular cases gives the solutions for different potentials: the Manning-Rosen, the Mobius square, the inversely quadratic Yukawa and the Hulthén potentials along with their bound state energies are obtained. 展开更多
关键词 Schrödinger Equation Mobius Potential Manning-Rosen Potential Quadratic Yukawa Potential Hulthén Potential Bound state Energies Wave Functions
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