The cross section for the process e^{+}e^{-}→π^{+}π^{-}J/ψ is measured precisely at center-of-mass energies from 3.77 to 4.60 GeV using 9 fb^{-1} of data collected with the BESIII detector operating ...at the BEPCII storage ring. Two resonant structures are observed in a fit to the cross section. The first resonance has a mass of (4222.0±3.1±1.4) MeV/c^{2} and a width of (44.1±4.3±2.0) MeV, while the second one has a mass of (4320.0±10.4±7.0) MeV/c^{2} and a width of (101.4_{-19.7}^{+25.3}±10.2) MeV, where the first errors are statistical and second ones are systematic. The first resonance agrees with the Y(4260) resonance reported by previous experiments. The precision of its resonant parameters is improved significantly. The second resonance is observed in e^{+}e^{-}→π^{+}π^{-}J/ψ for the first time. The statistical significance of this resonance is estimated to be larger than 7.6σ. The mass and width of the second resonance agree with the Y(4360) resonance reported by the BABAR and Belle experiments within errors. Finally, the Y(4008) resonance previously observed by the Belle experiment is not confirmed in the description of the BESIII data.
We report results on the searches of weakly interacting massive particles (WIMPs) with sub-GeV masses (mχ) via WIMP-nucleus spin-independent scattering with Migdal effect incorporated. Analysis on ...time-integrated (TI) and annual modulation (AM) effects on CDEX-1B data are performed, with 737.1 kg day exposure and 160 eVee threshold for TI analysis, and 1107.5 kg day exposure and 250 eVee threshold for AM analysis. The sensitive windows in mχ are expanded by an order of magnitude to lower DM masses with Migdal effect incorporated. New limits on σχNSI at 90% confidence level are derived as 2×10−32∼7×10−35 cm2 for TI analysis at mχ∼50–180 MeV/c2, and 3×10−32∼9×10−38 cm2 for AM analysis at mχ∼75 MeV/c2–3.0 GeV/c2.
We report the first results of a light weakly interacting massive particles (WIMPs) search from the CDEX-10 experiment with a 10 kg germanium detector array immersed in liquid nitrogen at the China ...Jinping Underground Laboratory with a physics data size of 102.8 kg day. At an analysis threshold of 160 eVee, improved limits of 8×10^{-42} and 3×10^{-36} cm^{2} at a 90% confidence level on spin-independent and spin-dependent WIMP-nucleon cross sections, respectively, at a WIMP mass (m_{χ}) of 5 GeV/c^{2} are achieved. The lower reach of m_{χ} is extended to 2 GeV/c^{2}.
A study using 144 one-day-old Arbor Acres broilers was conducted to assess the effects of dried ginger root (Zingiber officinale) that was processed to particle sizes of 300, 149, 74, 37, and 8.4 μm ...on growth performance, antioxidant status, and serum metabolites of broiler chickens. The birds were housed in 24 wire cages in an environmentally controlled room. Dietary treatments were no supplementation (control) and supplementation with ginger root processed to 5 particle sizes at the level of 5 g/kg of diet. Average daily gain, ADFI, and feed conversion rate of chicks of each cage were measured weekly. Blood samples from 8 broilers per treatment were obtained at d 21 and 42 of the experiment to determine antioxidant enzymatic activities and metabolites in the serum, and the birds were subsequently killed to determine carcass yield and abdominal fat content. All broilers had similar ADFI or feed conversion rate over the entire experimental period. However, broilers supplemented with ginger powder tended to have higher ADG and had greater (P = 0.014) carcass yield compared with that of the control. Supplementation of ginger increased (P < 0.001) activities of total superoxide dismutase and glutathione peroxidase but reduced (P < 0.01) concentrations of malondialdehyde and cholesterol in serum of broilers at 21 and 42 d of age. Concentration of total protein in serum of ginger-supplemented broilers tended (P = 0.092) to be higher at 21 d and was higher (P = 0.002) at 42 d of age compared with that of control broilers. Reducing particle size of ginger powder linearly reduced (P < 0.05) cholesterol (d 21) and linearly increased (P < 0.05) glutathione peroxidase (d 21), total superoxide dismutase (d 42), and total protein (d 21 and 42). Supplementation of ginger at the level of 5 g/kg improved antioxidant status of broilers and the efficacy was enhanced as the particle size was reduced from 300 to 37 μm.
The microstructures, texture and mechanical behaviors of as-extruded Mg-xLi sheets (x = 1, 2, 3; wt%) were investigated by the optical microscope, X-ray diffraction (XRD), electron back scattered ...diffraction (EBSD) and uniaxial tension test. The results showed that the as-extruded Mg-3Li sheet possessed a bimodal microstructure with two different grain sizes of 9.6µm and 3.7µm, respectively. Even the coarse grains of Mg-3Li were finer than the grains of Mg-(1,2)Li sheets. Meanwhile, the as-extruded Mg-3Li sheet showed higher strength and ductility compared to other two sheets. Especially, as the Li content increased from 2wt% to 3wt%, the ultimate tensile strength (UTS), the elongation to failure and the strain hardening exponent (n-value) along the transverse direction (TD) were enhanced by ~ 16%, 70% and 17%, respectively. The macro-texture and the orientation distribution characteristic implied that large amounts of prismatic and pyramidal slips were activated in the Mg-3 Li alloy during the extrusion process, while only basal slip was observed in the Mg-(1,2) Li alloys. The non-basal slips led to more potential nucleation sites and a better coordination for the deformation, resulting in the bimodal fine microstructure and better comprehensive mechanical properties of the as-extruded Mg-3Li sheet.
A 12‐week feeding trial was conducted to determine dietary choline requirement for juvenile Megalobrama amblycephala. The basal diet was formulated to contain 310 g kg−1 diet from vitamin‐free casein ...and gelatine. Choline chloride was supplemented to the basal diet to formulate six purified diets containing 0, 250, 500, 1000, 2000 and 4000 mg kg−1, respectively. Each diet was randomly fed to quadrupled groups of Megalobrama amblycephala with initial average weight 1.84 ± 0.04 g in a flow‐through system. Results showed weight gain was increased significantly with increasing dietary choline levels (P < 0.01). Lipid content of liver decreased significantly as dietary choline concentration increased (P < 0.01), whereas lipid content of dressed carcass showed opposite trend (P < 0.01), and lipid content of whole‐body was unaffected by dietary choline supplementation. Broken‐ line regression of weight gain, liver and muscle choline concentration showed choline requirements of Megalobrama amblycephala of 1198, 1525 and 1365 mg kg−1, respectively. In addition, dietary choline supplementation significantly improved lipid content of dressed carcass but not the content of whole body of blunt snout bream.
Here, in an analysis of a 2.92 fb–1 data sample taken at 3.773 GeV with the BESIII detector operated at the BEPCII collider, we measure the absolute decay branching fractions to be B(D0 → K–e+νe) = ...(3.505 ± 0.014 ± 0.033)% and B(D0 → π–e+νe) = (0.295 ± 0.004 ± 0.003)%. From a study of the differential decay rates we obtain the products of hadronic form factor and the magnitude of the CKM matrix element $f$ $^{K}_{+}$(0)|Vcs| = 0.7172 ± 0.0025 ± 0.0035 and $f$ $^{π}_{+}$(0)|Vcd| = 0.1435 ± 0.0018 ± 0.0009.
We present results on light weakly interacting massive particle (WIMP) searches with annual modulation (AM) analysis on data from a 1-kg mass p-type point-contact germanium detector of the CDEX-1B ...experiment at the China Jinping Underground Laboratory. Datasets with a total live time of 3.2 yr within a 4.2-yr span are analyzed with analysis threshold of 250 eVee. Limits on WIMP-nucleus (χ-N) spin-independent cross sections as function of WIMP mass (m_{χ}) at 90% confidence level (C.L.) are derived using the dark matter halo model. Within the context of the standard halo model, the 90% C.L. allowed regions implied by the DAMA/LIBRA and CoGeNT AM-based analysis are excluded at >99.99% and 98% C.L., respectively. These results correspond to the best sensitivity at m_{χ}<6 GeV/c^{2} among WIMP AM measurements to date.
We study the e^{+}e^{-}→γωJ/ψ process using 11.6 fb^{-1} e^{+}e^{-} annihilation data taken at center-of-mass energies from sqrts=4.008 GeV to 4.600 GeV with the BESIII detector at the BEPCII ...storage ring. The X(3872) resonance is observed for the first time in the ωJ/ψ system with a significance of more than 5σ. The relative decay ratio of X(3872)→ωJ/ψ and π^{+}π^{-}J/ψ is measured to be R=1.6_{-0.3}^{+0.4}±0.2, where the first uncertainty is statistical and the second systematic (the same hereafter). The sqrts-dependent cross section of e^{+}e^{-}→γX(3872) is also measured and investigated, and it can be described by a single Breit-Wigner resonance, referred to as the Y(4200), with a mass of 4200.6_{-13.3}^{+7.9}±3.0 MeV/c^{2} and a width of 115_{-26}^{+38}±12 MeV. In addition, to describe the ωJ/ψ mass distribution above 3.9 GeV/c^{2}, we need at least one additional Breit-Wigner resonance, labeled as X(3915), in the fit. The mass and width of the X(3915) are determined. The resonant parameters of the X(3915) agree with those of the Y(3940) in B→KωJ/ψ and of the X(3915) in γγ→ωJ/ψ observed by the Belle and BABAR experiments within errors.
Fe-based metallic glasses are known to have excellent soft magnetic properties, but restricted to the disastrous annealing embrittlement. A novel class of Fe84-xB14+x Zr2 (x = 0, 3, 6) metallic ...glasses with extraordinary annealing bending ductility and excellent soft magnetic properties were developed. The metallic glasses exhibit a high BS of 1.54–1.64 T and a low HC of 4.1–5.8 A/m. It is noteworthy that the Fe84B14Zr2 metallic glass exhibits the highest ductile to brittle transition temperature among all Fe-based metallic glasses reported to date and the ductile to brittle transition temperature decreases with the decrease of Fe content. Moreover, the well-distributed shear bands can still be formed during bending for Fe84B14Zr2 metallic glass after 680 K annealing. Pronounced β-relaxation peak has been observed for Fe84B14Zr2 metallic glass in its relaxation spectra. We demonstrate that the bending deformation ability is closely correlated to the β-relaxation. The underlying mechanism for the extraordinary bending deformation ability of Fe84B14Zr2 metallic glass after annealing can be attributed to the heterogeneous structure with plenty of loosely packed zones as revealed by the pronounced β-relaxation and high resolution transmission electron microscopy.
•Fe84B14Zr2 MG with good soft magnetic properties exhibits extraordinarily high DBT temperature.•Fe84B14Zr2 MG shows pronounced β-relaxation, relating to plenty of loosely packed zones.•The β-relaxation is regarded as an indication for the bending ability of metallic glasses after annealing.
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