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配注工艺对聚合物变分子量及变浓度的适应性 被引量:2
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作者 郑伟乔 《油气田地面工程》 北大核心 2012年第5期20-21,共2页
喇嘛甸油田北北块一区聚合物交替注入试验地面配套工艺由3号配制站提供聚合物母液,通过2号注入站注入聚合物。北北块一区2号注入站交替注入试验地面配注工艺通过调整改造能够满足试验要求。经过一个周期的交替注入节约药剂费用384万元,... 喇嘛甸油田北北块一区聚合物交替注入试验地面配套工艺由3号配制站提供聚合物母液,通过2号注入站注入聚合物。北北块一区2号注入站交替注入试验地面配注工艺通过调整改造能够满足试验要求。经过一个周期的交替注入节约药剂费用384万元,可见到明显的经济效果。为满足聚合物变分子量、变浓度注入试验要求,针对系统存在的问题,配制系统以新建配制站、能力转移和能力接替为措施,注入系统以新建注入站、预留能力、优选注入工艺为措施,以适应油田后续开发的需求。 展开更多
关键词 聚合物 变分子量 浓度 交替沣人
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Compressively Strained InGaAs/InGaAsP Quantum Well Distributed Feedback Laser at 1.74μm 被引量:1
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作者 潘教青 王圩 +4 位作者 朱洪亮 赵谦 王宝军 周帆 王鲁峰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第9期1688-1691,共4页
The compressively strained InGaAs/InGaAsP quantum well distributed feedback laser with ridge-wave- guide is fabricated at 1.74μm. It is grown by low-pressure metal organic chemical vapor deposition(MOCVD). A strain... The compressively strained InGaAs/InGaAsP quantum well distributed feedback laser with ridge-wave- guide is fabricated at 1.74μm. It is grown by low-pressure metal organic chemical vapor deposition(MOCVD). A strain buffer layer is used to avoid indium segregation. The threshold current of the device uncoated with length of 300μm is 11.5mA. The maximum output power is 14mW at 100mA. A side mode suppression ratio of 35.5dB is obtained. 展开更多
关键词 DFB laser compressive strain quantum well
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Radiative Decays of (0^+,1^+) Strange-Bottom Mesons 被引量:2
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作者 WANG Zhi-Gang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第7期91-98,共8页
In this article, we assume that the (0^+,1^+) strange-bottom mesons are the conventional bs mesons, and calculate the electromagnetic coupling constants d, g1, g2, and g3 using the light-cone QGD sum rules. Then w... In this article, we assume that the (0^+,1^+) strange-bottom mesons are the conventional bs mesons, and calculate the electromagnetic coupling constants d, g1, g2, and g3 using the light-cone QGD sum rules. Then we study the radiative decays Bs0→Bs^*γ, Bs1→Bsγ, Bs1→Bs^*γ, and Bs1→Bs0γ, and observe that the widths are rather narrow. We can search for the (0^+, 1^+) strange-bottom mesons in the invariant Bsπ^0 and Bs^*π^0 mass distributions in the strong decays or in the invariant Bs^*γ, and Bsγ mass distributions in the radiative decays. 展开更多
关键词 strange-bottom mesons light-cone QCD sum rules
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Expression and significance of homeodomain protein Cdx2 in gastric carcinoma and precancerous lesions 被引量:16
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作者 Rong Qin Na-Na Wang +1 位作者 Jing Chu Xian Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第25期3296-3302,共7页
AIM: To investigate the expression and significance of caudal-related homeobox transcription factor (Cdx2) in gastric carcinoma (GC) and precancerous lesions. METHODS: The expression of Cdx2 in GC, precancer- ou... AIM: To investigate the expression and significance of caudal-related homeobox transcription factor (Cdx2) in gastric carcinoma (GC) and precancerous lesions. METHODS: The expression of Cdx2 in GC, precancer- ous lesions and normal gastric mucosa were detected using immunohistochemical method. Hematoxylin and eosin staining, alcian blue/periodic acid-schiff and high iron diamine/alcian blue staining were used to classify intestinal metaplasia (IM) and GC. RESULTS: Cdx2 was not detected in normal gas- tric mucosa. Cdx2 expression was detected in 87.1% (101/116) of IM, 50% (36/72) of dysplasia and 48.2% (41/85) of GC. The Cdx2-expressing cells in IM were more prevalent than in dysplasia and carcinoma (P 〈 0.05). There was no relationship between Cdx2 ex- pression and the classification of IM or the degree of dysplasia. Expression of Cdx2 was significantly higher in intestinal-type carcinoma than in diffuse and mixed- type carcinoma (P 〈 0.05). Positive expression of Cdx2was mainly found in moderately to well differentiated GC. There was a negative association between nuclear Cdx2 expression and lymph node metastasis and tumor, nodes, metastasis stage of GC (P 〈 0.05). The patients with Cdx2-positive expression showed a higher survival rate than those with Cdx2-negative expression (P = 0.038). Multivariate analysis revealed that the expres- sion of Cdx2 and lymph node metastasis were indepen- dent prognostic indicators of GC (P 〈 0.05). 展开更多
关键词 Caudal-related homeobox transcription fac-tor Stomach neoplasm Intestinal metaplasia Dyspla-sia IMMUNOHISTOCHEMISTRY
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On Feasibility of Variable Separation Method Based on Hamiltonian System for a Class of Plate Bending Equations 被引量:5
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作者 额布日力吐 阿拉坦仓 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第3期569-574,共6页
The eigenfunction system of infinite-dimensional Hamiltonian operators appearing in the bending problem of rectangular plate with two opposites simply supported is studied. At first, the completeness of the extended e... The eigenfunction system of infinite-dimensional Hamiltonian operators appearing in the bending problem of rectangular plate with two opposites simply supported is studied. At first, the completeness of the extended eigenfunction system in the sense of Cauchy's principal value is proved. Then the incompleteness of the extended eigenfunction system in general sense is proved. So the completeness of the symplectic orthogonal system of the infinite-dimensional Hamiltonian operator of this kind of plate bending equation is proved. At last the general solution of the infinite dimensional Hamiltonian system is equivalent to the solution function system series expansion, so it gives to theoretical basis of the methods of separation of variables based on Hamiltonian system for this kind of equations. 展开更多
关键词 plate bending equation infinite-dimensioanl Hamiltonian operator eigenfunction system COMPLETENESS general solution
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Exact Solution to (1+1)-Dimensional Higher-Order Schrodinger Equation via an Extended Mapping Approach
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作者 ZHU Hai-Ping ZHENG Chun-Long FANG Jian-Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1期127-130,共4页
Starting from a special variable transformation and with the help of an extended mapping approach, the high-order Schrodinger equation (n = 3, 4) is solved. A new family of variable separation solutions with arbitra... Starting from a special variable transformation and with the help of an extended mapping approach, the high-order Schrodinger equation (n = 3, 4) is solved. A new family of variable separation solutions with arbitrary functions is derived. 展开更多
关键词 extended mapping approach Schrodinger equation exact solution
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Quantum Mechanical Hilbert Transformation for Normally Ordering Coulomb Potential-Type Operators 被引量:1
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作者 FAN Hong-Yi FU Liang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2X期213-216,共4页
We show that the technique of integration within an ordered product of operators can be extended to Hilbert transform. In so doing we derive normally ordered expansion of Coulomb potential-type operators directly by u... We show that the technique of integration within an ordered product of operators can be extended to Hilbert transform. In so doing we derive normally ordered expansion of Coulomb potential-type operators directly by using the mathematical Hilbert transform formula. 展开更多
关键词 quantum Hilbert transform normally ordering Coulomb potential
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Error Thresholds in Single-Peak Gaussian Distributed Fitness Landscapes 被引量:1
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作者 FENG Xiao-Li GU Jian-Zhong +1 位作者 LI Yu-Xiao ZHUO Yi-Zhong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第4X期763-768,共6页
Based on the Eigen and Crow-Kimura models with a single-peak fitness landscape, we propose the fitness values of all sequence types to be Gausslan distributed random variables to incorporate the effects of the fluctua... Based on the Eigen and Crow-Kimura models with a single-peak fitness landscape, we propose the fitness values of all sequence types to be Gausslan distributed random variables to incorporate the effects of the fluctuations of the fitness landscapes (noise of environments) and investigate the concentration distribution and error threshold of quasispecies by performing an ensemble average within this theoretical framework. We find that a small fluctuation of the fitness landscape causes only a slight change in the concentration distribution and error threshold, which implies that the error threshold is stable against small perturbations. However, for a sizable fluctuation, quite different from the previous deterministic models, our statistical results show that the transition from quasi-species to error catastrophe is not so sharp, indicating that the error threshold is located within a certain range and has a shift toward a larger value. Our results are qualitatively in agreement with the experimental data and provide a new implication for antiviral strategies. 展开更多
关键词 QUASI-SPECIES error threshold Gaussian distributed fitness landscape
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Solutions and Conditional Lie-Backlund Symmetries of Quasi-linear Diffusion-Reaction Equations 被引量:1
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作者 ZUO Su-Li QU Chang-Zheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第1期6-12,共7页
New classes of exact solutions of the quasi-linear diffusion-reaction equations are obtained by seeking for the high-order conditional Lie-Baeklund symmetries of the considered equations. The method used here extends ... New classes of exact solutions of the quasi-linear diffusion-reaction equations are obtained by seeking for the high-order conditional Lie-Baeklund symmetries of the considered equations. The method used here extends the approaches of derivative-dependent functional separation of variables and the invariant subspace. Behavior to some solutions such as blow-up and quenching is also described. 展开更多
关键词 conditional Lie-Backlund symmetry exact solution quasi-linear diffusion-reaction equation
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Splitting and Restoration of Kondo Peak in a Deformed Molecule Quantum Dot Coupled to Ferromagnetic Electrodes
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作者 王瑞强 蒋开明 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第2期370-376,共7页
We adopt the nonequilibrium Green's function method to theoretically study the Kondo effect in a deformed molecule, which is treated as an electron-phonon interaction (EPI) system. The self-energy for phonon part i... We adopt the nonequilibrium Green's function method to theoretically study the Kondo effect in a deformed molecule, which is treated as an electron-phonon interaction (EPI) system. The self-energy for phonon part is calculated in the standard many-body diagrammatic expansion up to the second order in EPI strength. We find that the multiple phonon-assisted Kondo satellites arise besides the usual Kondo resonance. In the antiparallel magnetic configuration the splitting of main Kondo peak and phonon-assisted satellites only happen for asymmetrical dot-lead couplings, but it is free from the symmetry for the parallel magnetic configuration. The EPI strength and vibrational frequency can enhance the spin splitting of both main Kondo and satellites. It is shown that the suppressed zero-bias Kondo resonance can be restored by applying an external magnetic field, whose magnitude is dependent on the phononic effect remarkably. Although the asymmetry in tunnel coupling has no contribution to the restoration of spin splitting of Kondo peak, it can shrink the external field needed to switch tunneling magnetoresistance ratio between large negative dip and large positive peak. 展开更多
关键词 Kondo splitting molecular electronics magnetoresistance effect electron-phonon interaction
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A Quantum Dynamical Mode for the Control of Decoherence 被引量:1
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作者 HuangWan-Xia WangQin-Mou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第1期59-64,共6页
We present a quantum measurement model where the meter is taken to be a squeezed reservoir. life realize decoherence in macroscopic limits using Bogoliubov transformation, and this kind of system-meter coupling has a ... We present a quantum measurement model where the meter is taken to be a squeezed reservoir. life realize decoherence in macroscopic limits using Bogoliubov transformation, and this kind of system-meter coupling has a dramatic influence on decoherence. 展开更多
关键词 coherent states displace operators squeezing operators canonical transformation DECOHERENCE
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Study on Application of Hypervirial Therem in the Variational Method
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作者 DINGYi-Bing LIXue-Qian 《Communications in Theoretical Physics》 SCIE CAS CSCD 2002年第3期283-286,共4页
We discuss a methodology problem which is crucially important for solving the Sch?dinger equation in terms of the variational method. We present a complete analysis on the application of the hypervirial theorem for ju... We discuss a methodology problem which is crucially important for solving the Sch?dinger equation in terms of the variational method. We present a complete analysis on the application of the hypervirial theorem for judging the quality of the trial wavefunction without invoking the precise solutions. 展开更多
关键词 hypervirial theorem variational method linear potential Schrodinger equation
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Interaction Between Line Soliton and Algebraic Soliton for Asymmetric Nizhnik-Novikov-Veselov Equation 被引量:1
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作者 RUAN Hang-Yu LI Zhi-Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第6期1547-1552,共6页
Starting from the variable separation approach, the algebraic soliton solution and the solution describing the interaction between line soliton and algebraic soliton are obtained by selecting appropriate seed solution... Starting from the variable separation approach, the algebraic soliton solution and the solution describing the interaction between line soliton and algebraic soliton are obtained by selecting appropriate seed solution for (2+1)-dimensional ANNV equation. The behaviors of interactions are discussed in detail both analytically and graphically. It is shown that there are two kinds of singular interactions between line soliton and algebraic soliton: 1) the resonant interaction where the algebraic soliton propagates together with the line soliton and persists infinitely; 2) the extremely repulsive interaction where the algebraic soliton affects the motion of the line soliton infinitely apart. 展开更多
关键词 variable separation approach the interaction between line soliton and algebraic soliton (2+1)-dimensional ANNV equation
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Separation of Variable Treatment for Solving Time—Dependent Potentials
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作者 QIANShang-Wu GUZhi-Yu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第2期149-150,共2页
We use the separation of variable treatment to treat some time-dependent systems, and point out that the condition of separability is the same as the condition of existence of invariant, and the separation of variable... We use the separation of variable treatment to treat some time-dependent systems, and point out that the condition of separability is the same as the condition of existence of invariant, and the separation of variable treatment is interrelated with the quantum-invariant method and the propagator method. We directly use the separation of variable treatment to obtain the wavefunctions of the time-dependent Coulomb potential and the time-dependent Hulthén potential. 展开更多
关键词 time-dependent system separation of variable treatment time-dependent Coulomb potential time-dependent Hulthen potential WAVEFUNCTION
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Realization of the N(odd)-Dimensional Quantum Euclidean Space by Differential Operators
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作者 LIYun JINGSi-Cong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期175-178,共4页
The quantum Euclidean space is a kind of noncommutative space that is obtained from ordinary Euclidean space by deformation with parameter q. When N is odd, the structure of this space is similar to . Motivated by r... The quantum Euclidean space is a kind of noncommutative space that is obtained from ordinary Euclidean space by deformation with parameter q. When N is odd, the structure of this space is similar to . Motivated by realization of by differential operators in , we give such realization for and cases and generalize our results to (N odd) in this paper, that is, we show that the algebra of can be realized by differential operators acting on C<SUP>&#x221e;</SUP> functions on undeformed space . 展开更多
关键词 noncommutative quantum space differential operator
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Structure and Anti-influenza A(H1N1) Virus Activity of Three Polysaccharides from Eucheuma denticulatum 被引量:5
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作者 YU Guangli LI Miaomiao +6 位作者 WANG Wei LIU Xin ZHAO Xiaoliang LV Youjing LI Guangsheng JIAO Guangling ZHAO Xia 《Journal of Ocean University of China》 SCIE CAS 2012年第4期527-532,共6页
Three polysaccharides (EW, EH and EA) were prepared from a red alga Eucheuma denticulatum by sequential extraction with cold water, hot water and sodium hydroxide water solution. Their monosaccharide compositions, r... Three polysaccharides (EW, EH and EA) were prepared from a red alga Eucheuma denticulatum by sequential extraction with cold water, hot water and sodium hydroxide water solution. Their monosaccharide compositions, relative molecular mass and structural characterization were determined by gas chromatography, high performance liquid chromatography, fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy methods. EW was hybrid l/k/v-carrageenan (701/17k/13v-car- rabiose), EH was mainly t-carrageenan, and EA was mainly α-1,4-Glucan (88%) but mixed with small amount of t-carrageenan (12%). The relative molecular mass ofEW, EH and EA was 480, 580 and 510kDa, respectively. The anti-influenza A (H1N1) virus activity of these three polysaccharides was evaluated using the Madin-Darby canine kidney cells model. EW showed good anti-H1N1 virus activity, its ICso was 276.5 μg mL-1, and the inhibition rate to H1N1 virus was 52% when its concentration was 250 μgmL-1. The ICs0 of t-carrageenan EH was 366.4 μgmL1, whereas EA showed lower anti-H1N1 virus activity (IC50〉430μgmL-1). Available data obtained give positive evidence that the hybrid carrageenan EW from Eueheuma denticulatum can be used as potential anti-H1N1 virus inhibitor in future. 展开更多
关键词 Eucheuma denticulatum hybrid carrageenan STRUCTURE H1N1 virus
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Eigenfunctions of Five-Qubit XX Chain and Ground State Concurrence
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作者 LING Yin-Sheng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1295-1298,共4页
Use Jordan-Wigner transformation the eigenstates and eigenenergies of live qubits XX chain including external magnetic field are obtained. The concurrences Co,1 and Co,2 of ground state are obtained. For the ferromagn... Use Jordan-Wigner transformation the eigenstates and eigenenergies of live qubits XX chain including external magnetic field are obtained. The concurrences Co,1 and Co,2 of ground state are obtained. For the ferromagnetic, when [(√5 - 1)/2]|J| 〈 B ≤ |J|, the values of C0,1 and C0,2 are the same. The C0,2 is easily broken by temperature. 展开更多
关键词 XX chain ENTANGLEMENT Jordan-Wigner transformation CONCURRENCE
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Detailed Analysis of Quantum Phase Transitions Within the u(2) Algebra
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作者 L.Fortunato L.Sartori 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第10期589-593,共5页
We analyze in detail the quantum phase transitions that arise in models based on the u(2) algebraic description for bosonic systems with two types of scalar bosons. First we discuss the quantum phase transition that... We analyze in detail the quantum phase transitions that arise in models based on the u(2) algebraic description for bosonic systems with two types of scalar bosons. First we discuss the quantum phase transition that occurs in hamiltonians that admix the two dynamical symmetry chains u(2) u(1) and u(2) so(2) by diagonalizing the problem exactly in the u(1) basis. Then we apply the coherent state formalism to determine the energy functioned. Finally we show that a quantum phase transition of a different nature, but displaying similar characteristics, may arise also within a single chain just by including higher order terms in the hamiltonian. 展开更多
关键词 algebraic models Lie algebra quantum phase transitions Lipkin model
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Synthesis of modified polyacrylamide with high content of hydroxamate groups and settling performance of red mud 被引量:2
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作者 刘锦伟 胡慧萍 +3 位作者 王梦 陈湘攀 陈启元 丁治英 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第6期2073-2080,共8页
Hydroxamated polyacrylamide(HPAM) was synthesized from polyacrylamide(PAM) with high relative molecular mass under the optimum reaction conditions(p H 12 and a molar ratio of hydroxylamine to amide groups of 1.5 ... Hydroxamated polyacrylamide(HPAM) was synthesized from polyacrylamide(PAM) with high relative molecular mass under the optimum reaction conditions(p H 12 and a molar ratio of hydroxylamine to amide groups of 1.5 at 50 ℃for 12 h). The hydroxamate groups of HPAM were verified by Fourier transform infrared spectrum(FT-IR). 46%(molar fration) hydroxamate groups and 23%(molar fraction) carbonyl groups on HPAM were determined by conductometric titration combined with Kjeldahl's microanalysis method. The settling performance achieved at different flocculant dosages was investigated with high goethite-containing red mud slurry of simulated Bayer process synthesized in laboratory. It turns out that the settling performance of high goethite-containing red mud was better with HPAM. The average settling rate of red mud in the first 5 min and the turbidity of supernatant after settling for 30 min are 2.36 m/h and 507 NTU, respectively, at a flocculant dosage of 120 g/t, which is similar to that achieved with Hx-600. 展开更多
关键词 hydroxamated polyacrylamide symhesis red mud settling performance
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B→K0^*(1430)K Decays in Perturbative QCD Approach
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作者 刘新 肖振军 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第3期540-544,共5页
In this article, we calculate the branching ratios of B→K0^* (1430)K decays by employing the pertur-bative QCD (pQCD) approach at leading order. We perform the evaluations in the two scenarios for the scalar mes... In this article, we calculate the branching ratios of B→K0^* (1430)K decays by employing the pertur-bative QCD (pQCD) approach at leading order. We perform the evaluations in the two scenarios for the scalar meson spectrum. We find that (i) The leading order pQCD predictions for the branching ratio Br(B^+→K^+K0^*(1430)^0)are in good agreement with the experimental upper limit in both scenarios, while the pQCD predictions for other considered B→K0^*(1430)K decay modes are also presented and will be tested by the LHC experiments; (ii) The annihilation contributions play an important role in these considered decays, for B^0→K0^*(1430)^±K^± decays,for example,which are found to be (1-4)×10^-6. 展开更多
关键词 B meson decays branching ratios the perturbative QCD approach
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