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New Physics Effects on Rare Decays B_u^+→π^+■^+■^-, ρ^+■^+■-in a Top Quark Two-Higgs-Doublet Model
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作者 SONG Hai-Zhen LU Lin-Xia LU Gong-Ru 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期696-702,共7页
Using the form factors from light-cone sum rules, we study the branching ratios and forward-backward asymmetries (FBAs) of the exclusive decays Bu^+→π^+e^+e^- and Bu^+ →ρ^+e^+e^- (e= e,μ) in the standar... Using the form factors from light-cone sum rules, we study the branching ratios and forward-backward asymmetries (FBAs) of the exclusive decays Bu^+→π^+e^+e^- and Bu^+ →ρ^+e^+e^- (e= e,μ) in the standard model (SM) and the top quark two-Higgs-doublet model (T2HDM). From the numerical results, we find that the new physics contributions cannot provide very large enhancement to the branching ratios and the theoretical predictions are in good agreement with the SM ones. The T2HDM effects on FBAs of these decays are small. Precision measurements of the dilepton invariant mass distributions, especially in the lower dilepton mass region, and the FBAs in the decays Bu^+ → π^+ (ρ^+ )e^+ e^- will greatly help in discriminating among the SM and the new physics models. 展开更多
关键词 new physics effects rare decay two-Higgs-doublet model branching ratio forward-backward asymmetry
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Ba(d)^o-Ba(d)^o Mixing and New Physics Effects in a Top Quark Two-Higgs Doublet Model
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作者 LU Lin-Xia XIAO Zhen-Jun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1099-1105,共7页
We calculate the new physics contributions to the neutral Bd^o and Ba^o meson mass splitting △Md and △Ma induced by the box diagrams involving the charged-Higgs bosons in the top quark two-Higgs doublet model (T2HD... We calculate the new physics contributions to the neutral Bd^o and Ba^o meson mass splitting △Md and △Ma induced by the box diagrams involving the charged-Higgs bosons in the top quark two-Higgs doublet model (T2HDM). Using the precision data, we obtain the bounds on the parameter space of the T2HDM: (a) For fixed MH = 400 GeV and 5= [0°, 60°], the upper bound on tan β is tan β≤ 30 after the inclusion of major theoretical uncertainties; (b) For the case of tan β≤ 20, a light charged Higgs boson with a mass around 300 GeV is allowed; and (c) The bounds on tan β and MH are strongly correlated: a smaller (larger) tan β means a lighter (heavier) charged Higgs boson. 展开更多
关键词 B meson mixing new physics effects two-Higgs-doublet model
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Grapevine-like high entropy oxide composites boost high-performance lithium sulfur batteries as bifunctional interlayers
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作者 Huarong Fan Yubing Si +3 位作者 Yiming Zhang Fulong Zhu Xin Wang Yongzhu Fu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第3期565-572,共8页
Lithium-sulfur batteries(LSBs)with high energy densities have been demonstrated the potential for energy-intensive demand applications.However,their commercial applicability is hampered by hysteretic electrode reactio... Lithium-sulfur batteries(LSBs)with high energy densities have been demonstrated the potential for energy-intensive demand applications.However,their commercial applicability is hampered by hysteretic electrode reaction kinetics and the shuttle effect of lithium polysulfides(LiPSs).In this work,an interlayer consisting of high-entropy metal oxide(Cu_(0.7)Fe_(0.6)Mn_(0.4)Ni_(0.6)Sn_(0.5))O_(4) grown on carbon nanofibers(HEO/CNFs)is designed for LSBs.The CNFs with highly porous networks provide transport pathways for Li^(+) and e^(-),as well as a physical sieve effect to limit LiPSs crossover.In particular,the grapevine-like HEO nanoparticles generate metal-sulfur bonds with LiPSs,efficiently anchoring active materials.The unique structure and function of the interlayer enable the LSBs with superior electrochemical performance,i.e.,the high specific capacity of 1381 mAh g^(-1) at 0.1 C and 561 mAh g^(-1) at 6 C.This work presents a facile strategy for exploiting high-performance LSBs. 展开更多
关键词 Electrospun carbon nanofibers Grapevine-like morphology Hierarchical physical sieve effect High-entropy induced chemisorption Lithium-sulfur battery
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Building Blocks of Nature
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作者 Hans Joachim Dudek 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1226-1303,共78页
By means of a representation of the elementary objects by the Lagrange density and by the commutators of the communication relations, correlations can be formed using the Fourier transform, which under the conditions ... By means of a representation of the elementary objects by the Lagrange density and by the commutators of the communication relations, correlations can be formed using the Fourier transform, which under the conditions of the Hamilton principle, describes correlation structures of the elementary objects with oscillator properties. The correlation structures obtained in this way are characterized by physical information, the essential component of which is the action. The correlation structures describe the physical properties and their interactions under the sole condition of the Hamilton’s principle. The structure, the properties and the interactions of elementary objects can be led back in this way to a fundamental four dimensional structure, which is therefore in their different modifications the building block of nature. With the presented method, an alternative interpretation of elementary physical effects to quantum mechanics is obtained. This report provides an overview of the fundamentals and statements of physical information theory and its consequences for understanding the nature of elementary objects. 展开更多
关键词 Hamilton Principle as Global Law in physics Physical Information Generated by Action Correlation Space Mass and Charge Formation Interpretation of Physical effects
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Effects of different sources of carbohydrates on intake, digestibility, chewing, and performance of Holstein dairy cows 被引量:5
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作者 Simin Poorkasegaran Asadollah Teimouri Yansari 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第2期188-198,共11页
To investigate the effects of different sources of carbohydrates on intake, digestibility, chewing, and performance, nine lactating Holstein dairy cows (day in milk= 100±21 d; body weight=645.7 ± 26.5 kg) ... To investigate the effects of different sources of carbohydrates on intake, digestibility, chewing, and performance, nine lactating Holstein dairy cows (day in milk= 100±21 d; body weight=645.7 ± 26.5 kg) were allotted to a 3 × 3 Latin square design at three 23-d periods. The three treatments included 34.91% (B), 18.87% (BC), and 18.86% (BB) barley that in treatment B was partially replaced with only corn or corn plus beet pulp in treatments BC and BB, respectively. The concentration of starch and neutral detergent soluble carbohydrate varied (22.2, 20.2, and 14.5; 13.6, 15.9, and 20.1% of DM in treatments B, BC, and BB, respectively). Cows in treatment BB showed a higher DMI and improved digestibility of DM, NDF, and EE compared with treatments B or BC Ruminal pH was higher in cows fed on BB (6.83) compared with those that received B or BC treatments (6.62 and 6.73, respectively). A lower proportion of propionate accompanied the higher pH in the BB group; however, a greater proportion of acetate and acetate: propionate ratio was observed compared with cows fed either on the B or BC diet. Moreover, cows fed on the BB diet showed the lowest ruminal passage rate and longest ruminal and total retention time. Eating time did not differ among treatments, rumination time was greater among cows fed on the BB diet compared with the others, whereas total chewing activity was greater than those fed on BC, but similar to those fed on B. The treatments showed no effect on milk yield. Partially replacing barley with corn or beet pulp resulted in an increase in milk fat and a lower protein concentration. Changing dietary NFC with that of a different degradability thus altered intake, chewing activity, ruminal environment, retention time or passage rate, and lactation performance. The results of this study showed that beet pulp with a higher NDF and a detergent-soluble carbohydrate or pectin established a more consistent ruminal mat than barley and corn, thus resulting in higher mean retention time and chewing activity, whereas no changes in 3.5% ECM and milk fat were observed. 展开更多
关键词 Chewing activity Dairy cow Detergent-soluble carbohydrate Fiber Neutral detergent fiber Physically effective fiber Ruminal characteristics
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EFFECT OF TOTAL IRRADIATION DOSE ON MOSFETs/SOI
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作者 高剑侠 严荣良 +3 位作者 任迪远 林成鲁 李金华 竺士扬 《Nuclear Science and Techniques》 SCIE CAS CSCD 1994年第4期236-240,共5页
The MOSFETs are built on SIMOX material, the chide positive charge, interface state, threshold voltage and leakage current of MOSFETs/SOI after 60Co-rirradiation are measured with I-V technique. The results indicate t... The MOSFETs are built on SIMOX material, the chide positive charge, interface state, threshold voltage and leakage current of MOSFETs/SOI after 60Co-rirradiation are measured with I-V technique. The results indicate that the accumulation rate of chide charge density is more than that of interface state density in dose range of 0-3×104Gy (Si), and the 'on' radiation bias is worst case for NMOSFET and PMOSFET. 展开更多
关键词 Oxide charge Interface state Threshold voltage Leakage current MOSFET Physical radiation effect
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Study on effect of different physical treatments on fragility of RBC
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《中国输血杂志》 CAS CSCD 2001年第S1期341-,共1页
关键词 Study on effect of different physical treatments on fragility of RBC
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Classification of Complex Reservoirs in Superimposed Basins of Western China 被引量:11
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作者 PANG Xiongqi ZHOU Xinyuan +3 位作者 LIN Changsong HUO Zhipeng LUO Xiaorong PANG Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第5期1011-1034,共24页
Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed b... Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed basins. The distinct differences between these basins and monotype basins are their discontinuous stratigraphic sedimentation, stratigraphic structure and stratigraphic stress-strain action over geological history. Based on the correlation of chronological age on structural sections, superimposed basins can be divided into five types in this study: (1) continuous sedimentation type superimposed basins, (2) middle and late stratigraphic superimposed basins, (3) early and late stratigraphic superimposed basins, (4) early and middle stratigraphic superimposed basins, and (5) long-term exposed superimposed basins. Multiple source-reservoir-caprock assemblages have developed in such basins. In addition, multi-stage hydrocarbon generation and expulsion, multiple sources, polycyclic hydrocarbon accumulation and multiple-type hydrocarbon reservoirs adjustment, reformation and destruction have occurred in these basins. The complex reservoirs that have been discovered widely in the superimposed basins to date have remarkably different geologic features from primary reservoirs, and the root causes of this are folding, denudation and the fracture effect caused by multiphase tectonic events in the superimposed basins as well as associated seepage, diffusion, spilling, oxidation, degradation and cracking. Based on their genesis characteristics, complex reservoirs are divided into five categories: (1) primary reservoirs, (2) trap adjustment type reservoirs, (3) component variant reservoirs, (4) phase conversion type reservoirs and (5) scale-reformed reservoirs. 展开更多
关键词 complex reservoirs tectonic event physically destructive effect chemically destructiveeffect western China's superimposed basins
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Mesoscale Numerical Simulation Study of Warm Fog Dissipation by Salt Particles Seeding 被引量:2
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作者 Hui HE Xueliang GUO +2 位作者 Xiang'e LIU Qian GAO Xingcan JIA 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第5期579-592,共14页
Based on the dynamic framework of WRF and Morrison 2-moment explicit cloud scheme, a salt-seeding scheme was developed and used to simulate the dissipation of a warm fog event during 6–7 November 2009 in the Beijing ... Based on the dynamic framework of WRF and Morrison 2-moment explicit cloud scheme, a salt-seeding scheme was developed and used to simulate the dissipation of a warm fog event during 6–7 November 2009 in the Beijing and Tianjin area. The seeding effect and its physical mechanism were studied. The results indicate that when seeding fog with salt particles sized 80 μm and at a quantity of 6 gm^(-2) at the fog top, the seeding effect near the ground surface layer is negative in the beginning period, and then a positive seeding effect begins to appear at 18 min, with the best effect appearing at 21 min after seeding operation. The positive effect can last about 35 min. The microphysical mechanism of the warm fog dissipation is because of the evaporation due to the water vapor condensation on the salt particles and coalescence with salt particles.The process of fog water coalescence with salt particles contributed mostly to this warm fog dissipation. Furthermore, two series of sensitivity experiments were performed to study the seeding effect under different seeding amounts and salt particles sizes. The results show that seeding fog with salt particles sized of 80 μm can have the best seeding effect, and the seeding effect is negative when the salt particle size is less than 10 μm. For salt particles sized 80 μm, the best seeding effect, with corresponding visibility of 380 m, can be achieved when the seeding amount is 30 g m^(-2). 展开更多
关键词 warm fog fog dissipation salt-seeding scheme physical mechanism seeding effect
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Noise Shielding Using Acoustic Metamaterials
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作者 刘斌 黄吉平 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第3期560-564,共5页
We exploit theoretically a class of rectangular cylindrical devices for noise shielding by using acoustic metamateriais. The function of noise shielding is justified by both the far-field and near-field full-wave simu... We exploit theoretically a class of rectangular cylindrical devices for noise shielding by using acoustic metamateriais. The function of noise shielding is justified by both the far-field and near-field full-wave simulations based on the finite element method. The enlargement of equivalent acoustic scattering cross sections is revealed to be the physical mechanism for this function. This work makes it possible to design a window with both noise shielding and air flow. 展开更多
关键词 general linear acoustics ULTRASONICS quantum acoustics physical effects of sound structural acoustics and vibration
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Definition and expression of non-symmetric physical properties in space for uniaxial crystals
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作者 Xiaojie Guo Lijuan Chen +2 位作者 Zeliang Gao Xin Yin Xutang Tao 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第9期412-420,共9页
The anisotropic physical property is the most noteworthy feature of crystals.In this paper,the subscript change method is used to analyze the sign changes of different tensors describing physical properties in uniaxia... The anisotropic physical property is the most noteworthy feature of crystals.In this paper,the subscript change method is used to analyze the sign changes of different tensors describing physical properties in uniaxial crystals.The distribution of some physical properties in special point groups exhibits non-symmetry in eight quadrants,which should attract the attention of crystal research.The difference between the crystallographic and physical coordinate systems and the lack of crystal symmetry operations are considered to be the origins of the non-symmetry.To avoid ambiguities and difficulties in characterizing and applying crystal physical properties,eight quadrants in space should be clarified.Hence,we proposed the use of piezoelectric properties to define the positive direction of the optical coordinate axis prior to the research and applications of optical properties. 展开更多
关键词 uniaxial crystals effective physical constant space distributions the positive direction of optical coordinate axis
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Influence of Structure Parameters on Performance of the Thermoelectric Module
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作者 杜群贵 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第3期464-468,共5页
A numerical model of thermoelectric module (TEM) is created by academic analysis,and the impacts of the resistance ratio and thermoelement size on the output power and thermoelectric efficiency of the TEM are analyz... A numerical model of thermoelectric module (TEM) is created by academic analysis,and the impacts of the resistance ratio and thermoelement size on the output power and thermoelectric efficiency of the TEM are analyzed by the MATLAB numerical calculation.The numerical model is validated by the ANSYS thermal,electrical,and structural coupling simulation.The effects of the variable physical property parameters and contact effect on the output power and thermoelectric efficiency are evaluated,and the concept of aspect ratio optimal domain is proposed,which provides a new design approach for the TEM. 展开更多
关键词 thermoelectric module (TEM) thermoelement contact effect variable physical property parameters output power thermoelectric efficiency
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Physical effect on transition from blocking to conducting state of barrier-type thyristor
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作者 李海蓉 李思渊 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2010年第12期33-37,共5页
The transition of the barrier-type thyristor (BTH) from blocking to conducting-state occurs between two entirely contrary physical states with great disparity in nature. The physical effects and mechanisms of the tr... The transition of the barrier-type thyristor (BTH) from blocking to conducting-state occurs between two entirely contrary physical states with great disparity in nature. The physical effects and mechanisms of the transition are studied in depth. The features of the transition snapback point are analyzed in detail. The transition snapback point has duality and is just the position where the barrier is flattened. It has a significant influence on the capture crosssection of the hole and high-level hole lifetime, resulting in the device entering into deep base conductance modulation. The physical nature of the negative differential resistance segment I-V characteristics is studied. It is testified by using experimental data that the deep conductance modulation is the basic feature and the linchpin of the transition process. The conditions and physical mechanisms of conductance modulation are investigated. The related physical subjects, including the flattening of the channel barrier, the buildup of the double injection, the formation of the plasma, the realization of the high-level injection, the elimination of the gate junction depletion region, the deep conductance modulation, and the increase in the hole's lifetime are all discussed in this paper. 展开更多
关键词 barrier-type thyristor negative differential resistance physical effect conductance modulation
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Failure behavior analysis of phased-mission systems considering functional and physical isolation effects
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作者 Ying CHEN Ze WANG Rui KANG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第10期195-207,共13页
Phased-Mission Systems(PMS)are widely applied in aerospace,telecommunication and intelligent systems for multiple,consecutive and non-overlapping phases of missions.The phasedependent stresses and system structure cau... Phased-Mission Systems(PMS)are widely applied in aerospace,telecommunication and intelligent systems for multiple,consecutive and non-overlapping phases of missions.The phasedependent stresses and system structure cause some difficulties to the reliability analysis of PMSs.In this paper,we analyze the physical isolation effects on the degradation speeds and across-phase damage accumulations of failure mechanisms.And,some corresponding reliability and unreliability formulas are derived.Besides,a hierarchical Binary Decision Diagram(BDD)-based modeling method is proposed for incorporating functional and physical isolation effects into BDD models,and the analytical method with phase algebras is introduced for studying the failure behavior of PMS with functional dependence.In the case study,we evaluate the collision avoidance system of a fixed-wing unmanned aerial vehicle as an example to demonstrate the proposed modeling and analysis method.Results show that the physical isolation effects have significant influences on the degradations of components,which deserves detailed analysis for a more practical and realistic PMS’s failure behavior. 展开更多
关键词 Failure mechanism Phase-dependent damage accumulation Phase-dependent degradation Physical isolation effect Reliability evaluation
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Leading order relativistic hyperon-nucleon interactions in chiral effective field theory
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作者 李凯文 任修磊 +1 位作者 耿立升 龙炳蔚 《Chinese Physics C》 SCIE CAS CSCD 2018年第1期111-121,共11页
We apply a recently proposed covariant power counting in nucleon-nucleon interactions to study strangeness S =-1 ΛN-Σ N interactions in chiral effective field theory. At leading order, Lorentz invariance introduces ... We apply a recently proposed covariant power counting in nucleon-nucleon interactions to study strangeness S =-1 ΛN-Σ N interactions in chiral effective field theory. At leading order, Lorentz invariance introduces 12 low energy constants, in contrast to the heavy baryon approach, where only five appear. The Kadyshevsky equation is adopted to resum the potential in order to account for the non-perturbative nature of hyperon-nucleon interactions.A fit to the 36 hyperon-nucleon scattering data points yields χ2 16, which is comparable with the sophisticated phenomenological models and the next-to-leading order heavy baryon approach. However, one cannot achieve a simultaneous description of the nucleon-nucleon phase shifts and strangeness S =-1 hyperon-nucleon scattering data at leading order. 展开更多
关键词 hyperon-nucleon interactions covariant chiral effective field theory hypernuclear physics
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