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911.
Condo GT Handler T Shimony J Abe K Armenteros R Austern M Bacon TC Ballam J Bingham HH Brau JE Braune K Brick D Bugg WM Butler JM Cameron W Cohn HO Colley DC Dado S Diamond R Dingus P Erickson R Falicov A Field RC Fortney LR Franek B Fujiwara N Glanzman T Godfrey IM Goldberg JJ Goshaw AT Hall G Hancock ER Hargis HJ Hart EL Harwin MJ Hasegawa K Hulsizer RI Jobes M Kafka T Kalmus GE Kelsey DP Kent J Kitagaki T Levy A Lucas PW Mann WA McCrory ES Merenyi R Milburn R Milstene C Moffeit KC Napier A 《Physical review D: Particles and fields》1991,43(9):2787-2791
912.
913.
K. E. Shestermanov A. N. Vasiliev J. Butler A. A. Derevshchikov P. Kasper V. V. Kiselev V. I. Kravtsov Y. Kubota R. Kutschke Yu. A. Matulenko N. G. Minaev V. V. Mochalov D. A. Morozov L. V. Nogach M. Rovere A. V. Ryazantsev P. A. Semenov S. Stone A. V. Uzunian J. Yarba 《Physics of Atomic Nuclei》2007,70(6):1058-1073
A precise measurement of the angle α in the CKM triangle is very important for a complete test of the Standard Model. A theoretically clean method to extract
α is provided by B
0 → ρπ decays. Monte Carlo simulations to obtain the BTeV reconstruction efficiency and to estimate the signal-to-background ratio
for these decays were performed. Finally the time-dependent Dalitz plot analysis, using the isospin amplitude formalism for
tree and penguin contributions, was carried out. It was shown that, in one year of data taking, BTeV could achieve an accuracy
on α better than 5°.
The text was submitted by the authors in English 相似文献
914.
Sa Tu Junfeng Hu Tane Butler Hanchen Wang Youguang Zhang Weisheng Zhao Simon Granville Haiming Yu 《Physics letters. A》2019,383(7):670-673
We report the anomalous Nernst effect in trilayers containing a thin film of the half-metallic ferromagnetic Heusler alloy Co2Fe0.4Mn0.6Si with perpendicular magnetic anisotropy. The structure is MgO/CFMS/Pd and we have studied the variation of anomalous Hall and Nernst effects as a function of CFMS and Pd thickness. The anomalous Nernst coefficient reaches 0.5 μV/K at room temperature and we have observed a strong dependence of the anomalous Nernst coefficient on the thickness of both layers. Our results indicate that inducing perpendicular magnetic anisotropy in a strongly spin-polarising Heusler alloy such as CFMS is very promising for new thermoelectric devices based on exploiting the anomalous Nernst effect. 相似文献
915.
Brookman Brian Butler Owen Ciaralli Laura Horsky Monika Laurent Caroline Noblett Tracey Örnemark Ulf Patriarca Marina Sibbesen Lorens P. Tiikkainen Ulla van Putten Kees Robouch Piotr 《Accreditation and quality assurance》2019,24(1):93-101
Accreditation and Quality Assurance - A summary of the working group discussions on proficiency testing (PT) and external quality assessment (EQA) held at the Eurachem Workshop, Portorož,... 相似文献
916.
Andrew T. Rhead Richard Butler Giles W. Hunt 《International Journal of Solids and Structures》2008,45(16):4349-4361
An analytical model for prediction of compressive fatigue threshold strains in composite plates with barely visible impact damage (BVID) is presented. The model represents the complex damage morphology as a single circular delamination at a critical level and calculates the strain at which thin-film buckling of the circular delaminated region occurs. The threshold strain is defined as the strain at which the strain energy release rate for the fracture of post-buckled delaminated plies along the delamination is equal to the critical Mode I value (G1C) for the resin. The model predicts the critical through-thickness level for delamination, the stability of delamination growth and also the sensitivity to experimental error in geometric measurements of the damage area. Results obtained using the model show an agreement of fatigue strain to within 4% of experimental values for four sets of data reported in the literature. 相似文献
917.
Alterobactin A is a siderophore produced by the oceanic bacterium Alteromonas luteoviolacea. The thermodynamic stability constant of the ferric alterobactin A (Alt-A) complex was estimated from electrochemical measurements on the basis of a previously reported linear relationship between the reduction potentials and the pH-independent stability constants for known iron(III) complexes. The reduction potential of the ferric alterobactin A complex determined by square wave voltammetry is -0.972 V vs SCE and reversible, corresponding to a thermodynamic stability constant of 10(51+/-2). Potentiometric titration of Fe(III)-Alt-A shows the release of six protons on complexation of Fe(III) to Alt-A. The 1H NMR resonances of the Ga(III)-Alt-A complex show that the C-4, C-5, and C-6 catecholate protons and the C(alpha) and C(beta) protons of both beta-hydroxyaspartate moieties are shifted downfield relative to the free ligand, which along with the potentiometric titration data is consistent with a complex in which Fe(III) is coordinated by both catecholate oxygen atoms and both oxygen atoms of each beta-hydroxyaspartate. The UV-vis spectrum of Fe(III)-Alt-A is invariant over the pH range 4-9, indicating the coordination does not change over a wide pH range. In addition, in the absence of a coordinated metal ion, the serine ester of Alt-A hydrolyzes forming Alt-B. 相似文献
918.
Brownian dynamics simulations of the behavior of suspensions of fibers demonstrate that the scaling of the rotational diffusivity with respect to the number density (nL3) is a sensitive function of the thickness and the parameter L2D(R0)/D(T0), where D(R0) is the rotational diffusivity at infinite dilution, D(T0) is the average center-of-mass diffusivity at infinite dilution, and L is the fiber length. Existing theories for the long-time rotational diffusivities of rigid fibers in the semidilute and concentrated regimes fail to accurately account for the relationship with the dilute values of the rotational and translational diffusivities of the various physical models used to simulate the fibers. The concentration regime studied in this work ranges from a number density of nL3 approximately 0-150, which is below the transition from an isotropic to nematic state. The effect of the fiber thickness was studied by performing simulations of rods with aspect ratios (fiber length over diameter) of 25, 50, and 500, as well as performing projections for infinitely thin fibers. The excluded volume of the rods was enforced through the use of short-range potentials. For a rod with an aspect ratio of 50 with a parameter of L2D(R0)/D(T0)=9, which corresponds to a slender-body model of the individual fibers, the rotational diffusivity (D(R)) scales as D(R)/D(R0) approximately (nL3)(-1.9) in the concentration regime of 70 < or = nL3 < or = 150. Similarly with a parameter of L2D(R0)/D(T0)=4, corresponding to a rigid-dumbbell model, the rotational diffusivity scales as D(R)/D(R0) approximately (nL3)(-1.1) over the same range of concentrations. For rods with aspect ratios of 25, it is observed that a difference in the scaling is seen for L2D(R0)/D(T0) approximately < 8, with higher values of this ratio exhibiting essentially the same scaling. Additional values of the ratio L2D(R0)/D(T0) were investigated to determine the overall behavior of the suspension dynamics with respect to this parameter. These findings resolve discrepancies between simulation results for rotational diffusivities reported by previous investigators and provide new insights for the development of an accurate theory for the diffusivity of rigid rods suspended in solution. 相似文献
919.
Luminescence from a square planar [Pd(SCN)(4)](2-) complex shows very large increases in intensity and lifetime from ambient pressures up to 27 kbar. The band maximum shows a blue-shift of approximately 29 cm(-1)/kbar. These spectroscopic observations can be rationalized qualitatively by considering multiple effects, and they underline the strong interrelation between molecular structure, energies, and geometries of excited electronic states, and optical properties. 相似文献
920.
The problem of efficiency vs fairness is considered in relation to the splitting of costs for shared facilities between users. This is considered as a result of a problem of sharing the cost of the provision of central computing facilities between different faculties in a large university, but the basic problem is widespread. A linear programming model is considered in order to minimise cost. The dual of this model is shown to correspond to an efficient allocation of costs. An alternative optimal dual solution is shown to give a ‘fair’ solution according to criteria resulting from cooperative game theory. 相似文献