The numbers of psi(3686) events accumulated by the BESIII detector for the data taken during 2009 and 2012 are determined to be (107.0 +/- 0.8)x10(6) and (341.1 +/- 2.1)x10(6), respectively, by ...counting inclusive hadronic events, where the uncertainties are systematic and the statistical uncertainties are negligible. The number of events for the sample taken in 2009 is consistent with that of the previous measurement. The total number of psi(3686) events for the two data taking periods is (448.1 +/- 2.9) x 10(6).
Born cross sections for the processes e+e−→ωη and e+e−→ωπ0 have been determined for center-of-mass energies between 2.00 and 3.08 GeV with the BESIII detector at the BEPCII collider. The results ...obtained in this work are consistent with previous measurements but with improved precision. Two resonant structures are observed. In the e+e−→ωη cross sections, a resonance with a mass of (2176±24±3)MeV/c2 and a width of (89±50±5)MeV is observed with a significance of 6.2σ. Its properties are consistent with the ϕ(2170). In the e+e−→ωπ0 cross sections, a resonance denoted Y(2040) is observed with a significance of more than 10σ. Its mass and width are determined to be (2034±13±9)MeV/c2 and (234±30±25)MeV, respectively, where the first uncertainties are statistical and the second ones are systematic.
By analyzing 7.33 fb −1 of e + e − annihilation data collected at center-of-mass energies between 4.128 and 4.226 GeV with the BESIII detector, we report the observation of the semileptonic decay D ...+ s → η′μ + ν μ , with a statistical significance larger than 10σ, and the measurements of the D + s → ημ + ν μ and D + s → η′μ + ν μ decay dynamics for the first time. The branching fractions of D + s → ημ + ν μ and D+s→η′μ + νμ are determined to be (2.235±0.051 stat ±0.052 syst )% and (0.801±0.055 stat ±0.028 syst )%, respectively, with precision improved by factors of 6.0 and 6.6 compared to the previous best measurements. Combined with the results for the decays D + s → ηe + ν e and D + s → η′e + ν e , the ratios of the decay widths are examined both inclusively and in several ℓ+ν ℓ four-momentum transfer ranges. No evidence for lepton flavor universality violation is found within the current statistics. The products of the hadronic form factors f η(') +,0 (0) and the c → s Cabibbo-Kobayashi-Maskawa matrix element |V cs | are determined. The results based on the two-parameter series expansion are f η +,0 (0)|V cs |=0.452±0.010 stat ±0.007 syst and f η′ +,0 (0)|V cs |=0.504±0.037 stat ±0.012 syst , which help to constrain present models on f η(') +,0 (0). The forward-backward asymmetries are determined to be ⟨A η FB ⟩=−0.059±0.031 stat ±0.005 syst and ⟨A η′ FB ⟩=−0.064±0.079 stat ±0.006 syst for the first time, which are consistent with the theoretical calculation.
The hydrodynamic problem of a cone entering the water surface through the free-fall motion has been analysed based on velocity potential theory. The fluid is assumed incompressible and the gravity ...effect has been ignored. The three dimensional (3D) problem is solved in the cylindrical coordinate system. Axisymmetric flow field is assumed, which has reduced the problem virtually to a two dimensional (2D) one, although the governing equation is no longer Laplacian. The boundary element method is used at each time step. The auxiliary function method has been adopted to decouple the motion of the cone from the fluid flow. Calculated results are compared with those published previously, both from simulation and based on experiments, and good agreement is found. Further simulations are made to investigate the effects of deadrise angle.
A bstract Based on e + e − collision data collected at center-of-mass energies from 2.000 to 3.080 GeV by the BESIII detector at the BEPCII collider, a partial wave analysis is performed for the ...process e + e − → $$ {K}_S^0{K}_L^0 $$ K S 0 K L 0 π 0 . The results allow the Born cross sections of the process e + e − → $$ {K}_S^0{K}_L^0 $$ K S 0 K L 0 π 0 , as well as its subprocesses e + e − → K ∗ (892) 0 $$ \overline{K} $$ K ¯ 0 and $$ {K}_2^{\ast } $$ K 2 ∗ (1430) 0 $$ \overline{K} $$ K ¯ 0 to be measured. The Born cross sections for e + e − → $$ {K}_S^0{K}_L^0 $$ K S 0 K L 0 π 0 are consistent with previous measurements by BaBar, but with substantially improved precision. The Born cross section lineshape of the process e + e − K ∗ (892) 0 $$ \overline{K} $$ K ¯ 0 is consistent with a vector meson state around 2.2 GeV with a significance of 3.2 σ . A Breit-Wigner fit determines its mass as M Y = (2164 . 7 ± 9 . 1 ± 3 . 1) MeV /c 2 and its width as Γ Y = (32 . 4 ± 21 . 0 ± 1 . 8) MeV.
Wheat-Dasypyrum villosum translocated chromosomes T6V#2S•6AL and T6V#4S•6DL are known to confer excellent resistance to wheat powdery mildew (PM). However, it is difficult to distinguish the two ...sources of PM resistance genes through multi-pathotype testing because to date no virulence for them has been found. To reveal the relationship between the PM resistance genes from the two translocations, the sequence of the Stpk-V gene, a key member of powdery mildew resistance locus Pm21, was used as a reference to isolate homologous genes from a D. villosum accession No.1026 and its derivatives 6V#4(6D) disomic substitution (DS) line RW15 and T6V#4S•6DL translocation line Pm97033. Two genes Stpk-V2 and Stpk-V3 were cloned from No.1026. Sequence alignment showed that Stpk-V2 and Stpk-V3 shared 98.2 % and 96.2 % of their DNA and 99.3 % and 100 % of their amino acids in identity with Stpk-V. Compared with Stpk-V, a 22-bp direct sequence repeat and a miniature inverted-repeat transposable element (MITE) were found in the intron 4 of Stpk-V2 and Stpk-V3, respectively. However, Stpk-V2 was not present in DS line RW15 and translocation line Pm97033 based on the PCR result, indicating that Stpk-V2 did not contribute to the PM resistance of RW15 and Pm97033. In the promoter region, a 78-bp insertion was found not only in Stpk-V2 and Stpk-V3, but also in its orthologous gene Stpk-A of wheat. In addition, there was a 17 bp/8 bp deletion/insertion in the putative promoter of Stpk-V3 in comparison with that of Stpk-V/Stpk-V2. Real-time quantitative RT-PCR analysis indicated that the expression levels of Stpk-V and Stpk-V3 genes in the translocation lines were induced by the pathogen, but Stpk-V had a higher expression level than Stpk-V3 at 12 h after inoculation with Bgt. The diversity of Stpk-V gene will help to explore new resistance genes to PM in D. villosum for wheat breeding.
The logarithmic mean enthalpy difference, (LMED) method has been extensively used in evaluating the thermal performance of an air cooling coil under wet condition. The LMED method has been developed ...based on the assumption of unit Lewis Factor, i.e., Le
2/3
=
1. However, a number of previous studies have suggested that the Lewis Factor can actually deviate from being 1. Consequently, errors can be resulted in when calculating the total heat transfer rate of a wet cooling coil using the LMED method. Therefore, a modified LMED (m-LMED) method has been developed for calculating the total heat transfer rate under both unit and non-unit Lewis Factors and is reported in this paper. This m-LMED method has been validated by comparing its prediction of the total heat transfer rate to that from numerically solving the fundamental governing equations of heat and mass transfer of a wet cooling coil. The m-LMED method can therefore replace the LMED method for calculating the total heat transfer rate of a wet cooling coil under both unit and non-unit Lewis Factors.
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