664 Search Results

In this work, a single-channel slope-plate Modular and Membrane-less Phase Separation and Extraction (MPSE) device was fabricated using 3D printing. The slope-plate was designed with an insertable glass slide to enable surface modification with coatings. Self-assembled monolayers (SAMs) and perfluoropolyether (Zdol) coatings were applied to tailor surface wettability and enhance phase separation. Using a model biphasic system of water and hexadecane, both coatings significantly improved the separation efficiency compared to the uncoated device by promoting selective wetting. Building on these results, lithium extraction from a simulated saline solution was investigated using 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][NTf₂]) as the ionic liquid (IL) extractant.more » The IL effectively extracted Li⁺ from the aqueous phase in bulk extraction, demonstrating its potential for lithium recovery. However, the low interfacial tension between the IL and aqueous phases posed challenges for phase separation. The application of SAM and Zdol coatings effectively mitigated this issue. Overall, integrating tailored surface chemistry with the slope-plate MPSE design shows great promise as an efficient and scalable platform for studying liquid–liquid separation and optimizing ionic liquid–based extraction processes for lithium recovery from saline sources.« less

Using a sample of ( 2712.4 ± 14.3 ) × 10 6     ψ ( 3686 ) events collected with the BESIII detector, we perform a search for the isospin-violating decays χ c J → Λ Σ ¯   0 + c . c . ( J = 0 , 1 , 2 ) and η c → Λ Σ ¯   0 + c . c . No significant signal for χ c J or η c is observed in the Λ Σ ¯   0 invariant mass distribution. The upper limits on the branching fractions at the 90% confidencemore » level are set to be B ( χ c 0 → Λ Σ ¯   0 + c . c . ) < 1.5 × 10 − 6 , B ( χ c 1 → Λ Σ ¯   0 + c . c . ) < 1.6 × 10 − 6 , B ( χ c 2 → Λ Σ ¯   0 + c . c . ) < 1.7 × 10 − 6 , and B ( η c → Λ Σ ¯   0 + c . c . ) < 6.2 × 10 − 5 for the first time.« less

We report the fabrication of aluminum metal matrix composites (Al-MMCs) with hierarchical architectures via friction extrusion (FE), a scalable, single-step, solid-phase processing technique. Precursor pucks containing 0–15 vol% Al₂O₃ particles were extruded into fully dense AA6061-based composite rods. The FE induced a tree-ring-like architecture of concentric particle-rich and particle-lean bands, yielding refined grains in particle-rich regions and coarser grains elsewhere. At the nanoscale, magnesium in AA6061 selectively reacted with Al₂O₃ particles to form virus-like nodes, improving particle–matrix bonding. This multi-scale design strategy, combining mesoscale architecture, microscale grain refinement, and nanoscale interface engineering overcome the conventional strength–ductility trade-off. Tensile testing showedmore » substantial increases in yield and ultimate tensile strengths while retaining high ductility ( > 20%). Enhanced strain hardening, driven by the accumulation of geometrically necessary dislocations at interfaces, contributed to the performance. The hierarchical microstructure produced by FE demonstrates a promising pathway for scalable fabrication of lightweight MMCs for structural applications requiring a combined high strength and ductility.« less

High-pressure die cast (HPDC) AZ91 magnesium alloy is widely used in automotive components such as transmission housings and brackets for its excellent strength-to-weight ratio. Zinc-based cold spray coatings can be applied selectively to vulnerable areas to enhance corrosion resistance, minimize galvanic coupling with dissimilar metals, and eliminate the need for full-surface oxide coatings, making the process more efficient and targeted. A comprehensive evaluation of 16 combinations of nitrogen carrier gas temperatures and pressures led to the identification of an optimal range of process parameters, yielding Zn coatings with porosity <0.5 % by area, wear rates reduced by a factor ofmore » two compared to uncoated AZ91, and adhesion strengths up to 35 MPa. The enhanced mechanical performance of the coating is attributed to the low porosity and the formation of a metallurgical bond at the coating-substrate interface. Corrosion studies using macroscale potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) revealed a significant decrease in corrosion rate and a shift to more noble corrosion potentials (ZCP) for coated substrates. Furthermore, the Zn cold-sprayed samples exhibited significantly lower corrosion-induced evolved hydrogen content compared to the base AZ91 substrate and AZ91 coated with industrial coatings, demonstrating that the Zn layer effectively protects the substrate from the corrosive environment. Overall, cold spray Zn coatings significantly improve the mechanical and corrosion performance of AZ91 Mg alloys, addressing key material challenges and enabling their broader use in automotive applications.« less

Magnesium (Mg) alloys are ideal candidates for automotive applications due to their high strength to weight ratio, castability, recyclability etc., however, they lack corrosion and oxidation resistance. Solid-state deposition techniques, such as cold spray, have been demonstrated to enhance their corrosion resistance as it relies on the severe plastic deformation of powder particles upon impact with the substrate to form a metallurgical bond with the substrate and within the coating. At cold sprayed interfaces, a heterogeneous microstructure is formed that includes some porosity, oxides and intermetallics which can significantly affect coating performance. Thus, establishing a direct correlation between the interfacemore » microstructure and its properties can aid in designing optimal cold spray parameters. In this study, we investigated the microstructure and mechanical properties of a zinc (Zn) coating deposited on a high pressure die cast (HPDC) AZ91 Mg substrate via high resolution scanning transmission electron microscopy, in situ micro-tensile testing, and finite element method (FEM) modeling. Micro-tensile pillars fabricated using the plasma focused ion beam (PFIB) successfully isolates the coating-substrate interface within the gauge length. The average bond strength of Zn-Mg interface was determined to be ∼140 MPa with failure occurring partially at the interface and mostly into the coatings. A detailed microstructural characterization revealed evidence of a strong metallurgical bonding at the Zn-Mg interface and formation of the C14 MgZn₂ laves phase interlayer resulting in a mixed mode of fracture during the micro-tensile experiments. FEM modeling reveals the stress distribution along the interfaces and suggests that a MgZn₂ layer thickness between 200–400 nm is optimum to increase the bond strength and minimize the triaxiality. Such a site-specific interfacial analysis with correlative computational modeling provides crucial insight into the overall performance of cold spray interfaces.« less

Based on 12.0 fb⁻¹ of 𝑒⁺⁢𝑒⁻ collision data samples collected by the BESIII detector at center-of-mass energies from 4.1271 to 4.3583 GeV, a partial wave analysis is performed for the process 𝑒⁺⁢𝑒⁻ → 𝜋⁺⁢𝜋⁻⁢𝐽/𝜓. The cross sections for the subprocesses 𝑒⁺⁢𝑒⁻ → 𝜋⁺⁢𝑍_𝑐⁢(3900)⁻ + c.c. → 𝜋⁺⁢𝜋⁻⁢𝐽/𝜓, 𝑓₀⁡(980)⁢(→ 𝜋⁺⁢𝜋⁻)⁢𝐽/𝜓, and (𝜋⁺⁢𝜋⁻)_S−wave⁢𝐽/𝜓 are measured for the first time. The mass and width of the 𝑍_𝑐⁢(3900)^± are determined to be 3884.6 ± 0.7 ± 3.3 MeV/𝑐² and 37.2 ± 1.3 ± 6.6 MeV, respectively. The first errors are statistical and the second systematic. The final state (𝜋⁺⁢𝜋⁻)_S−wave⁢𝐽/𝜓 dominates the process 𝑒⁺⁢𝑒⁻ →more » 𝜋⁺⁢𝜋⁻⁢𝐽/𝜓. By analyzing the cross sections of 𝜋^±⁢𝑍_𝑐⁢(3900)^∓ and 𝑓₀⁡(980)⁢𝐽/𝜓, 𝑌⁡(4220) has been observed. Its mass and width are determined to be 4225.7 ± 4.1 ± 3.4 MeV/𝑐² and 57.5 ± 9.4 ± 12.1 MeV, respectively.« less

The first direct measurement of the relative phase between the strong and electromagnetic amplitudes for a J/ψ decaying into a vector-pseudoscalar final state is performed using 26 energy points of e⁺e⁻ annihilation data between 3.00 GeV and 3.12 GeV. The data sets were collected by the BESIII detector with a total integrated luminosity of 452 pb⁻¹. By investigating the interference pattern in the cross section lineshape of e⁺e⁻ → ϕη, the relative phase between the strong and electromagnetic amplitudes of J/ψ decay is determined to be within [133°, 228°] at 68% confidence level.

Using (2712 ± 14) × 106ψ(3686) events collected with the BESIII detector, we perform the first amplitude analysis of the radiative decay ψ3686→γKS0KS0$$$$ \psi (3686)\to \gamma {K}_S^0{K}_S^0 $$$$ within the mass region MKS0KS0<2.8$$$$ {M}_{K_S^0{K}_S^0}<2.8 $$$$ GeV/c2. Employing a one-channel K-matrix approach for the description of the dynamics of the KS0KS0$$$$ {K}_S^0{K}_S^0 $$$$ system, the data sample is well described with four poles for the f0-wave and three poles for the f2-wave. The determined pole positions are consistent with those of well-established resonance states. The observed f0 and f2 states are found to be in agreement with those produced in radiativemore » J/ψ decays. The production behaviors of f0 and f2 poles in ψ3686→γKS0KS0$$$$ \psi (3686)\to \gamma {K}_S^0{K}_S^0 $$$$ are qualified with their residues and the converted branching fractions. By comparing with J/ψ→γKS0KS0$$$$ J/\psi \to \gamma {K}_S^0{K}_S^0 $$$$ decay, the ratios Bψ3686→γf0,2BJ/ψ→γf0,2$$$$ \frac{\mathcal{B}\left(\psi (3686)\to \gamma {f}_{0,2}\right)}{\mathcal{B}\left(J/\psi \to \gamma {f}_{0,2}\right)} $$$$ are determined, which provides crucial experimental inputs on the internal structure of the f0,2 states, especially their potential mixing with glueball components.« less

We present the first amplitude analysis and branching fraction measurement of the decay $D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}{\pi }^0{\pi }^0$ , using $e^{+}{e}^{-}$ collision data collected with the BESIII detector at center-of-mass energies between 4.128 and 4.226 GeV corresponding to an integrated luminosity of $7.33{\mathrm{fb}}^{-1}$ , and report the first observation of the pure $W$ -annihilation decay $more »$ D s + → ω ρ + with a branching fraction of $(0.99\pm 0.08_{\mathrm{stat}}{{}_{-0.07}^{+0.05}}_{\mathrm{syst}})\%$ . In comparison to the low significance of the $\mathcal{D}$ wave in the decay $D_s^{+}\to \varphi {\rho }^{+}$ , the dominance of the $\mathcal{D}$ wave over the $\mathcal{S}$ and $\mathcal{P}$ waves, with a fraction of $(51.85\pm 7.28_{\mathrm{stat}}{{}_{-7.90}^{+4.83}}_{\mathrm{syst}})\%$ observed in the decay $D_s^{+}\to \omega {\rho }^{+}$ , provides crucial information for the “polarization puzzle,” as well as for the understanding of charm meson decays. The branching fraction of $D_s^{+}\to {\pi }^{+}{\pi }^{+}{\pi }^{-}{\pi }^0{\pi }^0$ is measured to be $(4.41\pm 0.15_{\mathrm{stat}}\pm 0.13_{\mathrm{syst}})\%$ . Moreover, the branching fraction of $D_s^{+}\to \varphi {\rho }^{+}$ is measured to be $(3.98\pm 0.33_{\mathrm{stat}}{{}_{-0.19}^{+0.21}}_{\mathrm{syst}})\%$ , and the $R_{\varphi }=\mathcal{B}(\varphi \to {\pi }^{+}{\pi }^{-}{\pi }^0)/\mathcal{B}(\varphi \to K^{+}{K}^{-})$ is determined to be ( $0.222\pm 0.019_{\mathrm{stat}}{{}_{-0.016}^{+0.016}}_{\mathrm{syst}}$ ), which is consistent with the previous measurement based on charm meson decays, but deviates from the results from $e^{+}{e}^{-}$ annihilation and $K-N$ scattering experiments by more than $3\sigma$ . Published by the American Physical Society 2025« less