Utilizing a data sample corresponding to an integrated luminosity of 2.93 fb-1 recorded by the BESIII detector at a center-of-mass energy of 3.773 GeV, we present an analysis of the decays ...D0→π-π0e+ve and D+→π-π+e+ve . Using a partial wave analysis, the π+π- S-wave contribution to D+→π-π+e+ve is observed for the first time besides the dominant P-wave contribution; the statistical significance is greater than 10σ with its measured fraction (25.7 ± 1.6 ± 1.1)%. We measure the branching fractions $\mathcal{B(D^0→p^-e^+v_e)}$ = (1.445 ± 0.058 ± 0.039) × 10-3, $\mathcal{B(D^+→p^0e^+v_e)}$ = (1.860 ± 0.070 ± 0.061) × 10-3 and $\mathcal{B(D^+→f_0(500)e^+v_e)}$, f0(500)→ π+π -) = (6.30 ± 0.43 ± 0.32) × 10-4. An upper limit of $\mathcal{B(D^+→f_0(980)e^+v_e)}$, f0(980)→π+π -) < 2.8 × 10-5 is set at the 90% confidence level. We also obtain the hadronic form factor ratios of D→ρe+ve at q2 = 0 assuming the single-pole dominance parameterization: rv = {V(0)/A1(0)} = 1.695 ± 0.083 ± 0.051, r2 = {A2(0)\A1(0)} = 0.845 ± 0.056 ± 0.039.
Large-strain ausforming and low-temperature bainite transformation were carried out in a medium C - Si rich alloy steel on a thermomechanical simulator. Then, temperature–time–transformation curves ...of the bainite transformation after ausforming at different temperatures were obtained by dilatometry. The effects of ausforming on transformation kinetics, microstructure, and hardness of samples were studied. Results show that the entire process of bainite transformation can be accelerated by ausforming. With decreasing ausforming temperature, the transformation rates greatly increased at the initial transformation stage but slightly decreased at the final stage. Compared with non-ausformed sample, not only was the maximum growth rate in the ausformed samples larger, but the maximum growth rate also appeared earlier. In addition, the maximum rate of the ausformed bainite transformation was increased and the time of reaching the maximum rate was shortened with decreasing the ausforming temperature. The effect of ausforming on bainite transformation kinetics depended not only on the ausforming temperature and strain but also on the isothermal transformation temperature. The reduction in transformation time was increased under decreased isothermal transformation temperature. Ausforming refined the bainite plates and increased the fraction of retained austenite formed in the subsequent low-temperature isothermal transformation. Consequently, nanostructured bainite with enhanced hardness was prepared in the medium C - Si rich alloy steel.
AbstractObjectivesTo estimate the effects of nationwide replacement of discretionary salt (used at table or during cooking) with potassium enriched salt substitute on morbidity and death from ...cardiovascular disease in China.DesignModelling study.SettingChina.PopulationAdult population in China, and specifically individuals with chronic kidney disease (about 17 million people).InterventionsComparative risk assessment models were used to estimate the effects of a nationwide intervention to replace discretionary dietary salt with potassium enriched salt substitutes (20-30% potassium chloride). The models incorporated existing data and corresponding uncertainties from randomised trials, the China National Survey of Chronic Kidney Disease, the Global Burden of Disease Study, and the Chronic Kidney Disease Prognosis Consortium.Main outcome measuresAverted deaths from cardiovascular disease, non-fatal events, and disability adjusted life years from a reduction in blood pressure were estimated after implementation of potassium enriched salt substitution. In individuals with chronic kidney disease, additional deaths from cardiovascular disease related to hyperkalaemia from increased intake of potassium were calculated. The net effects on deaths from cardiovascular disease were estimated as the difference and ratio of averted and additional deaths from cardiovascular disease.ResultsNationwide implementation of potassium enriched salt substitution could prevent about 461 000 (95% uncertainty interval 196 339 to 704 438) deaths annually from cardiovascular disease, corresponding to 11.0% (4.7% to 16.8%) of annual deaths from cardiovascular disease in China; 743 000 (305 803 to 1 273 098) non-fatal cardiovascular events annually; and 7.9 (3.3 to 12.9) million disability adjusted life years related to cardiovascular disease annually. The intervention could potentially produce an estimated 11 000 (6422 to 16 562) additional deaths related to hyperkalaemia in individuals with chronic kidney disease. The net effect would be about 450 000 (183 699 to 697 084) fewer deaths annually from cardiovascular disease in the overall population and 21 000 (1928 to 42 926) fewer deaths in individuals with chronic kidney disease. In deterministic sensitivity analyses, with changes to key model inputs and assumptions, net benefits were consistent in the total population and in individuals with chronic kidney disease, with averted deaths outweighing additional deaths.ConclusionsNationwide potassium enriched salt substitution in China was estimated to result in a substantial net benefit, preventing around one in nine deaths from cardiovascular disease overall. Taking account of the risks of hyperkalaemia, a substantial net benefit was also estimated for individuals with chronic kidney disease.
Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from ...astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.
We present Atacama Large Millimeter Array (ALMA) Cycle-0 observations of the CO (6-5) line emission (rest-frame frequency = 691.473 GHz) and of the 435 mum dust continuum emission in the nuclear ...region of NGC 34, a local luminous infrared galaxy at a distance of 84Mpc (1" = 407 pc) which contains a Seyfert 2 active galactic nucleus (AGN) and a nuclear starburst. The CO emission is well resolved by the ALMA beam (0".26 x (0".23), with an integrated flux of f sub((CO(6-5)) = 1004 (+ or -151) Jy km s super(-1). Both the morphology and kinematics of the CO (6-5) emission are rather regular, consistent with a compact rotating disk with a size of 200 pc. A significant emission feature is detected on the redshifted wing of the line profile at the frequency of the H super(13)CN (8-7) line, with an integrated flux of 17.7 + or - 2.1 (random) + or - 2.7(systematic) Jy km s super(-1). However, it cannot be ruled out that the feature is due to an outflow of warm dense gas with a mean velocity of 400 km s super(-1). The continuum is resolved into an elongated configuration, and the observed flux corresponds to a dust mass of M sub(dust) = 10 super(6.97+ or -0.13) M sub(middot in circle). An unresolved central core (radius Asymptotically = to 50 pc) contributes 28% of the continuum flux and 19% of the CO (6-5) flux, consistent with insignificant contributions of the AGN to both emissions. Both the CO (6-5) and continuum spatial distributions suggest a very high gas column density (gap super(4) M sub(middot in circle) pc super(-2)) in the nuclear region at radius lap100 pc.
The effect of nanoconfinement on the equilibrium free radical polymerization of methyl methacrylate (MMA) is investigated using differential scanning calorimetry. The ceiling temperature is shifted ...to lower temperatures in 13 nm diameter pores, with pore surface chemistry showing no significant effect. The results indicate that the change in the entropy of propagation decreases in nanopores due to confinement effects (i.e. ΔSp,conf is a more negative value than ΔSp,bulk). The change in the entropy of propagation is independent of temperature for the bulk equilibrium polymerization, whereas the change in the entropy of propagation in nanopores becomes less negative and more bulk-like with increasing polymerization temperature presumably due to the lower molecular weight chains produced at high temperature. The data suggest that our system is one of weak confinement with chain entropy scaling with molecular weight to the 1.1 power (i.e. ∼ N1.1).
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•The thermodynamics of nanoconfined free radical polymerization is studied using DSC.•The change in entropy for chain propagation becomes more negative in nanopores.•The equilibrium conversion and ceiling temperature decrease due to nanoconfinement.•Surface chemistry does not appear to have an effect at high reaction temperatures.•Chain entropy in the 13-nm pores scales with N1.1 indicating weak confinement.
The effects of tungsten carbide addition on the microstructure, mechanical properties and corrosion resistance of Ti(C,N)-based cermets prepared by the sinter-HIP method are investigated through ...scanning electron microscope, X-ray diffraction, electron back scattered diffraction, mechanical test and electrochemical method. The results show that the appropriate WC addition has an important influence on promoting the formation of core-rim microstructure of cermet, increasing the wettability of ceramic phase and binder phase, and improving the mechanical properties. Ti(C,N)-based cermet with 5 wt% WC addition has the highest hardness of 92.4 HRA and excellent wear resistance. However, excessive WC addition causes the appearance of slight white core phase containing plenty of W and Ti element in microstructure, which increases the fracture toughness, and reduces the hardness and wear resistance of cermet. Additionally, the electrochemical result shows that the addition of 5 wt% WC in cermet has the optimal corrosion resistance in 1 mol/L hydrochloric acid solution.
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