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Planck’s Oscillators at Low Temperatures and Haken’s Perturbation Approach to the Quantum Oscillators Reconsidered
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作者 Stanisław Olszewski 《Journal of Modern Physics》 2021年第12期1721-1728,共8页
In the first step the extremal values of the vibrational specific heat and entropy represented by the Planck oscillators at the low temperatures could be calculated. The positions of the extrema are defined by the dim... In the first step the extremal values of the vibrational specific heat and entropy represented by the Planck oscillators at the low temperatures could be calculated. The positions of the extrema are defined by the dimensionless ratios between the quanta of the vibrational energy and products of the actual temperature multiplied by the Boltzmann constant. It became evident that position of a local maximum obtained for the Planck’s average energy of a vibration mode and position of a local maximum of entropy are the same. In the next step the Haken’s time-dependent perturbation approach to the pair of quantum non-degenerate Schr<span style="white-space:nowrap;">?</span>dinger eigenstates of energy is re-examined. An averaging process done on the time variable leads to a very simple formula for the coefficients entering the perturbation terms. 展开更多
关键词 Planck’s Quantum Oscillators at Low Temperatures Calculation of the Extremal Specific Heat of the Oscillator Energy and Extremal Entropy Simplified Haken’s Time-Dependent approach to the perturbation Energy of a Non-Degenerate Quantum State
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Uptake and Storage of Anthropogenic CO_2 in the Pacific Ocean Estimated Using Two Modeling Approaches 被引量:9
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作者 李阳春 徐永福 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第4期795-809,共15页
A basin-wide ocean general circulation model (OGCM) of the Pacific Ocean is employed to estimate the uptake and storage of anthropogenic CO2 using two different simulation approaches. The simulation (named BIO) ma... A basin-wide ocean general circulation model (OGCM) of the Pacific Ocean is employed to estimate the uptake and storage of anthropogenic CO2 using two different simulation approaches. The simulation (named BIO) makes use of a carbon model with biological processes and full thermodynamic equations to calculate surface water partial pressure of CO2, whereas the other simulation (named PTB) makes use of a perturbation approach to calculate surface water partial pressure of anthropogenic CO2. The results from the two simulations agree well with the estimates based on observation data in most important aspects of the vertical distribution as well as the total inventory of anthropogenic carbon. The storage of anthropogenic carbon from BIO is closer to the observation-based estimate than that from PTB. The Revelle factor in 1994 obtained in BIO is generally larger than that obtained in PTB in the whole Pacific, except for the subtropical South Pacific. This, to large extent, leads to the difference in the surface anthropogenic CO2 concentration between the two runs. The relative difference in the annual uptake between the two runs is almost constant during the integration processes after 1850. This is probably not caused by dissolved inorganic carbon (DIC), but rather by a factor independent of time. In both runs, the rate of change in anthropogenic CO2 fluxes with time is consistent with the rate of change in the growth rate of atmospheric partial pressure of CO2. 展开更多
关键词 anthropogenic CO2 biological process perturbation approach Revelle factor FLUX
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Seismic response evaluation of the impact of corrosion on buried pipelines based on the Markov process
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作者 Liu Wei Li Jie 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2008年第3期295-303,共9页
Water distribution and gas supply systems are among the infrastructure systems that have many buried steel pipelines. Corrosion gradually appears inside and outside of the pipe walls over the service life of these pip... Water distribution and gas supply systems are among the infrastructure systems that have many buried steel pipelines. Corrosion gradually appears inside and outside of the pipe walls over the service life of these pipelines, the corrosion is primarily caused by the surrounding soil and the materials that flow through the pipelines. However, due to the uncertainty of the characteristics of the soil and materials, the size of the corrosion region is a stochastic variable. In this paper, using a homogeneous Markov process, a model is presented to simulate the occurrence of corrosion. Then, in combinations with a linear corrosion development model, the probability density function of the pipeline area corrosion percentage is derived. Based on the corrosion model, the pipeline seismic displacements and stresses are predicted. Furthermore, using the random perturbation approach, the mean and variance of the pipeline seismic response are given. To illustrate the validity of the proposed approach, a 200-meter long pipeline is numerically investigated and its random seismic response is obtained. 展开更多
关键词 PIPELINE CORROSION homogeneous Markov process elastic foundation beam random perturbation approach
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Role of Electromagnetic Dipole Operator in the Electroweak Penguin Dominated Vector Meson Decays of B Meson
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作者 吕才典 沈月龙 王伟 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第10期2684-2687,共4页
The pure annihilation type decays Dd^0→Фγand Bs→ργ receive only colour suppressed penguin contributions with a very small branching ratio in the standard model. When we include the previously neglected electroma... The pure annihilation type decays Dd^0→Фγand Bs→ργ receive only colour suppressed penguin contributions with a very small branching ratio in the standard model. When we include the previously neglected electromagnetic dipole operator, the branching ratios can be enhanced to R(^-Bd^0→Фγ)≈ 1×10^-11 and R(^-Bs→ργ)~(6 - 16) ×10^-10, which are one order magnitude larger than previous study using the QCD factorization approach. The new effect can also give a large contribution, of order 10^-9, to transverse polarization of B→Фρ and B →ωФ, which is comparable to the longitudinal part. These effects can be detected in the LHCb experiment and the super-B factories. 展开更多
关键词 PERTURBATIVE QCD approach HEAVY-QUARK LIMIT CP VIOLATION FORM-FACTORS FACTORIZATION POLARIZATION RARE
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General formula for phonon-assisted n-photon absorption in solids
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作者 邓洪祥 蒋晓东 +5 位作者 向霞 孙凯 袁晓东 郑万国 高飞 祖小涛 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第10期573-583,共11页
A general formula for phonon-assisted n-photon absorption in solids is obtained by (n + 1)-th order perturbation technique. The complicated calculation process for transition element of n-photon absorption is simpl... A general formula for phonon-assisted n-photon absorption in solids is obtained by (n + 1)-th order perturbation technique. The complicated calculation process for transition element of n-photon absorption is simply demonstrated by a diagram approach that is proposed in this work. We find that the transition element for the n-photon absorption has a simple form, i.e., it is just the first term of the n-th order fist kind Bessel function. 展开更多
关键词 general formula phonon-assisted photons absorption n order perturbation technique diagram approach intense laser
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B→K_0~*(1430)η^(') decays in the pQCD approach
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作者 刘新 张志清 肖振军 《Chinese Physics C》 SCIE CAS CSCD 2010年第2期157-164,共8页
Based on the assumption of two-quark structure of the scalar meson K0^*(1430), we calculate the CP-averaged branching ratios for B→K0^*(1430)η(') decays in the framework of the perturbative QCD (pQCD) app... Based on the assumption of two-quark structure of the scalar meson K0^*(1430), we calculate the CP-averaged branching ratios for B→K0^*(1430)η(') decays in the framework of the perturbative QCD (pQCD) approach here. We perform the evaluations in two scenarios for the scalar meson spectrum. We find that: (a) the pQCD predictions for Br(B→K0^*(1430)η(')) which are about 10^-5 10^-6, basically agree with the data within large theoretical uncertainty; (b) the agreement between the pQCD predictions and the data in Scenario Ⅰ is better than that in Scenario Ⅱ, which can be tested by the forthcoming LHC experiments; (c) the annihilation contributions play an important role for these considered decays. 展开更多
关键词 B meson perturbative QCD approach scalar meson branching ratio
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B→(J/ψ,η_c)K decays in the perturbative QCD approach
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作者 刘新 张志清 肖振军 《Chinese Physics C》 SCIE CAS CSCD 2010年第7期937-943,共7页
In this paper,we calculated the B →(J/ψ,ηc) K decays in the perturbative QCD(pQCD) factorization approach with the inclusion of the partial next-to-leading order(NLO) contributions. With the inclusion of the ... In this paper,we calculated the B →(J/ψ,ηc) K decays in the perturbative QCD(pQCD) factorization approach with the inclusion of the partial next-to-leading order(NLO) contributions. With the inclusion of the significant enhancement from the NLO vertex corrections,the NLO pQCD predictions for the branching ratios agree with the data within 2σ errors:Br(B0 → J/ψK0) = 5.2-+32..58×10-4,Br(B+ → J/ψK+) = 5.6-+32..79×10-4,Br(B0 →ηcK0) = 5.5-+22..30 × 10-4,Br(B+ →ηcK+) = 5.9-+22..51 × 10-4. 展开更多
关键词 B meson next-to-leading order corrections branching ratio perturbative QCD approach
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Reinvestigating B→PV decays by including contributions from Φ_(B2) with the perturbative QCD approach
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作者 杨悦玲 赵旭乐 +2 位作者 郎岚 黄金书 孙俊峰 《Chinese Physics C》 SCIE CAS CSCD 2022年第8期34-62,共29页
Considering the B mesonic wave function φ_(B2),B→PV decays are re studied in the leading order for three scenarios using the perturbative QCD approach within the standard model,where P=π and K,and V denotes the gro... Considering the B mesonic wave function φ_(B2),B→PV decays are re studied in the leading order for three scenarios using the perturbative QCD approach within the standard model,where P=π and K,and V denotes the ground SU(3) vector mesons.It is found that contributions from φ_(B2) can enhance most branching ratios and are helpful for improving the overall consistency of branching ratios between the updated calculations and available data,although there are still several discrepancies between the experimental and theoretical results. 展开更多
关键词 B→PV decays B mesonic wave function perturbative QCD approach branching ratio
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Resonance contributions fromχ_(c0)in charmless three-body hadronic B meson decays
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作者 张亚兰 王超 +1 位作者 林毅 肖振军 《Chinese Physics C》 SCIE CAS CSCD 2023年第4期148-154,共7页
Within the framework of perturbative QCD factorization,we investigate the nonfactorizable contributions to the factorization-forbidden quasi-two-body decays B_((s))→h_((χ)_(c0))→hπ^(+)π^(-)(K^(+)K^(-))with h=π,K... Within the framework of perturbative QCD factorization,we investigate the nonfactorizable contributions to the factorization-forbidden quasi-two-body decays B_((s))→h_((χ)_(c0))→hπ^(+)π^(-)(K^(+)K^(-))with h=π,K.We compare our predicted branching ratios for the B_(()(s))→K_(χc0)→Kπ^(+)π-(K^(+)K^(-))decay with available experiment data as well as predictions by other theoretical studies.The branching ratios of these decays are consistent with data and other theoretical predictions.However,in the Cabibbo-suppressed decays B_((s))→h_((χ)_(c0))→hπ^(+)π^(-)(K^(+)K^(-))with h=K^(0),π,the values of the branching ratios are of the order of 10^(-7)and 10^(-8).The ratio R_((χ)_(c0))between the decays B^(+)→π^(+)χ_(c0)→π^(+)π^(+)π^(-)and B^(+)→K^(+)χc0→K^(+)π^(+)π^(-)and the distribution of branching ratios for different decay modes in invariant mass are considered in this study. 展开更多
关键词 three-body B meson decays resonance contributions perturbative QCD factorization approach
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CONTACT ANALYSIS FOR FIBER-REINFORCED, DELAMINATED LAMINATES WITH KINEMATIC NONLINEARITY 被引量:7
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作者 Jianghong Xue Li Zi Hong Yuan Renhuai Liu 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2013年第4期388-402,共15页
A macro-micro analytical approach for the anti-penetrating contact problem at the interfaces of the delamination in symmetrically cross-plied,fiber-reinforced rectangular laminates is presented in this paper.The lamin... A macro-micro analytical approach for the anti-penetrating contact problem at the interfaces of the delamination in symmetrically cross-plied,fiber-reinforced rectangular laminates is presented in this paper.The laminate is simply supported and subjected to a uniform transverse load with a through-width delamination buried at the center position.A contact factor is defined to characterize the contact effect and determined using the micro-mechanics of composite material.By analyzing the kinematics of nonlinear deformation at the interfaces of the delamination,the contact force is derived.Asymptotic solutions from perturbation analysis are presented.It is found that the deformation of the laminate involves a global deflection and a local buckling.The antipenetrating contact effects are characterized by the local buckling and are intrinsic properties of the laminates,relying only on the geometries of the delamination and the material properties.Parametric analyses show that the location and size of the contact areas and the distribution of the contact force are hardly affected by the aspect ratio. 展开更多
关键词 rectangular laminate DELAMINATION contact effect perturbation approach nonlinear analysis
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Study of pure annihilation decays B_(d,s)→D^0~0
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作者 李营 华娟 《Chinese Physics C》 SCIE CAS CSCD 北大核心 2008年第10期781-787,共7页
Within the heavy quark limit and the hierarchy approximation λQCD 〈〈 mD〈〈 mB, we analyze the B → D^0D^-0 and Bs → D^0D^-0 decays, which occur purely via annihilation type diagrams. As a rough estimate, we calcu... Within the heavy quark limit and the hierarchy approximation λQCD 〈〈 mD〈〈 mB, we analyze the B → D^0D^-0 and Bs → D^0D^-0 decays, which occur purely via annihilation type diagrams. As a rough estimate, we calculate their branching ratios and CP asymmetries in the perturbative QCD (PQCD) approach. The branching ratio of B → D^0D^-0 is about 3.8 × 10^-5 that is just below the latest experimental upper limit. The branching ratio of Bs → D^0D^-0 is about 6.8 ×10^-4, which could be measured in LHC-b. From the calculation, it is found that this branching ratio is not sensitive to the weak phase angle γ. In these two decay modes, there exist CP asymmetries because of the interference between weak and strong interaction. However, these asymmetries are too small to be measured easily. 展开更多
关键词 perturbative QCD approach B meson CP violation
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Pure annihilation decays of B^(s)_(0)→a^(+)_(0)a^(−)_(0)and B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0)in the PQCD approac
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作者 陈禹同 蒋泽文 刘新 《Communications in Theoretical Physics》 SCIE CAS CSCD 2021年第4期82-91,共10页
We study the CP-averaged branching fractions and the CP-violating asymmetries in the pure annihilation decays of B^(s)_(0)→a^(+)_(0)a^(−)_(0)and B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0),where a_(0)[K^(∗)_(0)]denotes the scala... We study the CP-averaged branching fractions and the CP-violating asymmetries in the pure annihilation decays of B^(s)_(0)→a^(+)_(0)a^(−)_(0)and B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0),where a_(0)[K^(∗)_(0)]denotes the scalar a_(0)(980)and a_(0)(1450)[K^(∗)_(0)(800)(orκ)and K^(∗)_(0)(1430)],with the perturbative QCD factorization approach under the assumption of two-quark structure for the a_(0)and K^(∗)_(0)states.The numerical results show that the branching ratios of the B^(0)_(d)→K^(∗+)_(0)K^(∗−)_(0)decays are in the order of 10^(−6),while the decay rates of the B^(s)_(0)→a^(+)_(0)a^(−)_(0)modes are in the order of 10−5.In light of the measured modes with the same quark components in the pseudoscalar sector,namely,B^(0)_(d)→K^(+)k_(-)and B^(0)_(s)→π^(+)π_(−),the predictions for the considered decay modes in this work are expected to be measured at the Large Hadron Collider beauty and/or Belle-Ⅱexperiments in the(near)future.Meanwhile,it is of great interest to find that the twist-3 distribution amplitudesφ^(S)andφ^(T)with inclusion of the Gegenbauer polynomials for the scalar a_(0)(1450)and K^(∗)_(0)(1430)states in scenario 2 contribute slightly to the branching ratios while significantly to the CP violations in the B^(0)_(d)→K^(∗)_(0)(1430)+K^(∗)_(0)(1430)−and B^(0)_(s)→a_(0)(1450)+a_(0)(1450)−decays,which indicates that,compared to the asymptoticφ^(S)andφ^(T),these Gegenbauer polynomials could change the strong phases evidently in these pure annihilation decay channels.These predictions await for the future confirmation experimentally,which could further provide useful information to help explore the inner structure of the scalars and shed light on the annihilation decay mechanism. 展开更多
关键词 B meson decays perturbative QCD factorization approach light scalar mesons branching ratios CP-violating asymmetries
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Resonancesρ(1450)^(+)andρ(1700)^(+)in B→DKK decays
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作者 马爱军 王文飞 《Chinese Physics C》 SCIE CAS CSCD 2022年第5期38-43,共6页
The contributions for the kaon pair from the intermediate statesρ(1450)^(+) andρ(1700)^(+) in the decays B+→D¯^(0)K+K¯^(0),B^(0)→D−K+K¯^(0),and B^(0)_(s)→D−_(s)K+K¯^(0)are analyzed within the ... The contributions for the kaon pair from the intermediate statesρ(1450)^(+) andρ(1700)^(+) in the decays B+→D¯^(0)K+K¯^(0),B^(0)→D−K+K¯^(0),and B^(0)_(s)→D−_(s)K+K¯^(0)are analyzed within the perturbative QCD factorization approach.The decay amplitudes for all concerned decays in this work are dominated by the factorizable Feynman diagrams with the emission of the kaon pair,and the chargedρmesons should be of great importance in the KK channel of the related three-body B decays.Moreover,these quasi-two-body decays are CKM-favored,and the relevant branching ratios are predicted to be in the order of 10^(−5),which have the potential to be measured by experiments.It is also shown that the contributions of the subprocessesρ(1450,1700)^(+)→KK for the three-body B meson decays are considerable according to the total three-body branching fractions presented by Belle.Therefore,the decays B+→D¯^(0)K+K¯^(0),B^(0)→D−K+K¯^(0),and B^(0)_(s)→D−_(s)K^(+)K¯^(0)can be employed to study the properties ofρ(1450)andρ(1700)in the LHCb and Belle-II experiments. 展开更多
关键词 three-body B meson decays resonance contributions perturbative QCD factorization approach
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B→Kη^(,) decays in the SM with fourth generation fermions
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作者 程山 樊莹莹 肖振军 《Chinese Physics C》 SCIE CAS CSCD 2014年第7期9-13,共5页
By employing the perturbative QCD (pQCD) factorization approach, we calculate the new physics contributions to the four B→Kη(') decays in the Standard Model (SM) with a fourth generation of fermions (SM4), ... By employing the perturbative QCD (pQCD) factorization approach, we calculate the new physics contributions to the four B→Kη(') decays in the Standard Model (SM) with a fourth generation of fermions (SM4), induced by the loop diagrams involving t' quark. Within the considered parameter space of the SM4 we find that: (a) the next-to-leading order (NLO) pQCD predictions for the branching ratios and CP-violating asymmetries in both the SM and SM4 generally agree with the data within one standard deviation; (b) for Br(B→Kη), the inclusion of the fourth generation contributions can improve the agreement between the theoretical predictions and the data effectively; (c) however, for Br(B→Kη') the decrease due to t' loops is disfavored by the data; and, (d) the new physics corrections to the CP-violating asymmetries of the considered decays are only about 10%. 展开更多
关键词 perturbative QCD factorization approach B meson decays standard model with fourth generation CP violatoin
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