304 research outputs found
The System Dynamics Model in Electronic Products Closed-Loop Supply Chain Distribution Network with Three-Way Recovery and the Old-for-New Policy
With the technological developments and rapid changes in demand pattern, diverse varieties of electronic products are entering into the market with reduced lifecycle which leads to the environmental problems. The awareness of electronic products take-back and recovery has been increasing in electronic products supply chains. In this paper, we build a system dynamics model for electronic products closed-loop supply chain distribution network with the old-for-new policy and three electronic products recovery ways, namely, electronic products remanufacturing, electronic component reuse and remanufacturing, and electronic raw material recovery. In the simulation study, we investigate the significance of various factors including the old-for-new policy, collection and remanufacturing, their interactions and the type of their impact on bullwhip, and profitability through sensitivity analysis. Our results instruct that the old-for-new policy and three electronic products recovery ways can reduce the bullwhip effect in the retailers and the distributors and increases the profitability in the closed-loop supply chain distribution network
A single chemosensor for multiple analytes: fluorogenic and ratiometric absorbance detection of Zn²⁺, Mg²⁺ and F⁻, and its cell imaging
A simple coumarin based sensor 1 has been synthesized from the condensation reaction of 7-hydroxycoumarin and ethylenediamine via the intermediate 7-hydroxy-8-aldehyde-coumarin. As a multiple analysis sensor, 1 can monitor Zn²⁺ with the fluorescence enhanced at 457 nm, and ratiometric detection at 290 nm, 350 nm and 420 nm in DMF/H₂O (1/4, v/v) medium. Sensor 1 can also monitor Mg²⁺ with the fluorescence enhanced at 430 nm, and ratiometric detection at 290 nm, 370 nm and 430 nm in DMF medium through the interaction of chelation enhance fluorescence (CHEF) with metal ions. Furthermore, 1 also can monitor F⁻ with the fluorescence enhanced at 460 nm, and ratiometric detection at 290 nm and 390 nm in DMF medium simultaneously via hydrogen bonding and deprotonation with F− anion. Spectral titration, isothermal titration calorimetry and mass spectrometry revealed that the sensor formed a 1:1 complex with Mg²⁺, Zn²⁺ or F⁻, with stability constants of 4.5 × 10⁶, 3.4 × 10⁶, 8.0 × 10⁴ M⁻1 respectively. The complexation of the ions by 1 was an exothermic reaction driven by entropy processes. Furthermore, the sensor exhibits good membrane-permeability and was capable of monitoring at the intracellular Zn²⁺ level in living cells
CP asymmetry from resonance effect of B meson decay process with and K final states
We introduce the new resonance of , which produces some new strong phase associated with vector meson
resonance and thus can cause relatively large CP asymmetry at the range of
interferences. There are the resonances of , and due to the mixing
of vector mesons , , . We calculate the CP asymmetry from
the decay modes of . Meanwhile, the localised CP
asymmetries are presented and some detailed analysis can be found. The CP
asymmetry from the decay mode of is also presented in our framework which is well consisted
with LHC experiment. The introduced CP asymmetry can provide a favorable
theoretical support for the experimental exploration in the future
A reversible and visible colorimetric/fluorescent chemosensor for Al³⁺+ and F⁻ ions with a Large Stoke's shift
A quinoline-vinyl-dihydroxylphenyl linkage comprising a donor-π-bridge-acceptor structural motif, in which the quinoline serves as an electron-withdrawing core, has been synthesized and used as a fluorescent sensor (2) for the recognition of Al³⁺+ and F⁻ by colorimetry/fluorescence. The sensor 2 exhibited little fluorescence due to excited-state intramolecular proton transfer from the hydroxyl oxygens to the nitrogen of the quinoline moiety. By contrast, on coordination of Al³⁺+ or F⁻, sensor 2 afforded strong fluorescence. A reversible “off–on” optical switching mode has been constructed by sequential inputs from Al³⁺+ and F⁻ ions to the sensor 2 via different excitation and emission wavelengths. ¹H NMR and IR spectroscopic analysis revealed that the Al³⁺+ is coordinated to the quinoline nitrogen and phenolic oxygen atoms, whereas the F⁻ center is only coordinated by two phenolic oxygen atoms
Plaquette Singlet Transition, Magnetic Barocaloric Effect, and Spin Supersolidity in the Shastry-Sutherland Model
Inspired by recent experimental measurements [Guo \textit{et al.}, Phys. Rev.
Lett.~\textbf{124}, 206602 (2020); Jim\'enez \textit{et al.}, Nature
\textbf{592}, 370 (2021)] on frustrated quantum magnet SrCu(BO)
under combined pressure and magnetic fields, we study the related spin-
Shastry-Sutherland (SS) model using state-of-the-art tensor network methods. By
calculating thermodynamics, correlations and susceptibilities, we find, in zero
magnetic field, not only a line of first-order plaquette-singlet (PS) to
dimer-singlet phase transition ending with a critical point, but also
signatures of the ordered PS transition with its critical endpoint terminating
on this first-order line. Moreover, we uncover prominent magnetic barocaloric
responses, a novel type of quantum correlation induced cooling effect, in the
strongly fluctuating supercritical regime. Under finite fields, we identify a
quantum phase transition from the PS phase to the spin supersolid phase that
breaks simultaneously lattice translational and spin rotational symmetries. The
present findings on the SS model are accessible in current experiments and
would shed new light on exotic critical and supercritical phenomena in
archetypal frustrated quantum magnets.Comment: Close to the published version. 7 pages, 4 figures (SM 9 pages, 12
figures
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