The prediction of new fluorooxoborates as ultraviolet(UV)/deep ultraviolet(DUV)opto-electronic functional materials from a largely unexplored chemical space is a challenging *** has been suggested that the anionic fra...
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The prediction of new fluorooxoborates as ultraviolet(UV)/deep ultraviolet(DUV)opto-electronic functional materials from a largely unexplored chemical space is a challenging *** has been suggested that the anionic frameworks formed by B–O and B–O–F units significantly determine the physical properties of ***,the rational design of anionic frameworks could facilitate the materials discovery ***,we propose that a candidate anionic framework can be efficiently derived from an existing one by slightly altering its oxygen *** this idea,we hypothesized the existence of a 1D[B_(3)O_(5)F]_(∞)chain from the wellknown 2D[B_(6)O_(9)F_(2_)]_(∞)***,seven CaB_(3)O_(5)F structures with the expected anionic framework were successfully ***-principles calculations show that all these structures have potential in the UV/DUV birefringent or nonlinear optical(NLO)material field,indicating that the 1D[B_(3)O_(5)F]_(∞)chain is indeed a promising anionic framework for achieving UV/DUV birefringent and NLO performance.
Substantial NO_(x) emission mitigation is crucial for the synergistic reduction of particulate matter and ozone(O_(3))pollution in *** traditional air quality model does not consider heterogeneous HONO chemistry,leadi...
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Substantial NO_(x) emission mitigation is crucial for the synergistic reduction of particulate matter and ozone(O_(3))pollution in *** traditional air quality model does not consider heterogeneous HONO chemistry,leading to uncertainties in estimating the benefits of NO_(x) *** studies have shown that the parameterization of heterogeneous HONO formation increases both the simulated value of sulfate–nitrate–ammonium(SNA)and that of O_(3),thus adding the heterogeneous reactions of HONO into air quality models inevitably leads to changes in the estimated benefits of NO_(x) *** we investigated the changes in SNA and O_(3)concentrations from NO_(x) emission reduction before and after adding heterogeneous HONO reactions in the Community Multi-Scale Air Quality(CMAQ)*** heterogeneous HONO reactions in the simulation improved the benefits of NO_(x) reduction in terms of SNA control in *** 80%NO_(x) reduction,the reduction in SNA increased from 36.9%without considering heterogeneous HONO reactions to 42.8%with heterogeneous HONO *** reduction in the maximum daily 8h average(MDA8)O_(3)in summer caused by NO_(x) reduction increased slightly from 4.7%to 5.2%after adding heterogeneous HONO *** results in this study highlight the enhanced effectiveness of NO_(x) controls for the reduction of SNA and O_(3)after considering heterogeneous HONO formation in a complex chemical ambient,demonstrating the importance of NO_(x) controls in reducing PM2.5 and O_(3)pollution in China.
SnSe exhibits excellent thermoelectric performance in both n-and p-type single crystals,but its n-type polycrystals are restricted because of the lower electrical ***,we dually introduced rare earth element Ce and PbT...
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SnSe exhibits excellent thermoelectric performance in both n-and p-type single crystals,but its n-type polycrystals are restricted because of the lower electrical ***,we dually introduced rare earth element Ce and PbTe to optimize the thermoelectric properties of n-type SnSe *** is demonstrated that Ce is an effective cationic dopant to convert SnSe from p-to n-type conductor,and an enhanced peak zT value of∼0.9 at 823 K was obtained in Sn 0.97 Ce 0.03 Se due to the improved power ***,PbTe alloying not only reduced the band gap to increase the carrier concentration,but also enhanced the density-of-states effective mass,and hence further increased the power factor in the whole measured temperature ***,the lattice thermal conductivity was significantly reduced owing to the enhanced phonon scattering by the mass and strain *** a result,the peak zT value was increased to∼1.3 for Sn 0.9 Pb 0.07 Ce 0.03 Se 0.93 Te 0.07 together with a high average zT value of∼0.52 in the temperature range of 300 to 823 K.
The magnetic and electronic transport properties manipulated by spin-orbit torque have been devoted much attention as they show a great promise for future spintronic ***,the spin dependent transport properties of the ...
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The magnetic and electronic transport properties manipulated by spin-orbit torque have been devoted much attention as they show a great promise for future spintronic ***,the spin dependent transport properties of the facing-target sputtered Pt/Mn_(4)N bilayers on MgO(001)substrates have been investigated *** Hall resistivity of Pt/Mn_(4)N bilayers is strongly dependent on temperature,applied current intensity,Mn_(4)N and Pt layer *** temperature-dependent sign reversal of anomalous Hall resistivity appears in Pt/Mn_(4)N bilayers,which is dominated by the competition between the magnetic proximity and spin Hall ***,the magnitude of anomalous Hall resistivity can be manipulated by applied current *** critical and saturation currents are related to Mn_(4)N and Pt layer ***,a Dzyaloshinskii-Moriya interaction coefficient(D)of 5.63 mJ·m^(-2)is calculated in Pt/Mn_(4)N/MgO *** details of the anomalous Hall effects in Pt/Mn_(4)N bilayers are helpful to understand the interfacial effects between heavy metals and ferrimagnets.
To enhance the convergence capability of grey wolf optimizer (GWO), this research investigates an evolved GWO using weighted-leader strategy (WLS), namely WLSGWO. The key issue of WLS is realizing the adaptive adjustm...
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Modulation of the surface electron distribution is a challenging problem that determines the adsorption ability of catalytic ***,we address this challenge by bridging the inner and outer layers of the core–shell stru...
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Modulation of the surface electron distribution is a challenging problem that determines the adsorption ability of catalytic ***,we address this challenge by bridging the inner and outer layers of the core–shell structure through the bridge Br *** shell wrapped copper bromide nanorods(CuBr@C)are constructed for the first time by chemical vapour deposition with hexabromobenzene(HBB).HBB pyrolysis provides both bridge Br atom and C *** C shell protects the stability of the internal halide structure,while the bridge Br atom triggers the rearrangement of the surface electrons and exhibits excellent electrocatalytic ***,the hydrogen evolution reaction(HER)activity of CuBr@C is significantly better than that of commercial N-doped carbon nanotubes,surpassing commercial Pt/C at over 200 mA·cm^(−2).Density functional theory(DFT)calculations reveal that bridge Br atoms inspire aggregation of delocalized electrons on C-shell surfaces,leading to optimization of hydrogen adsorption energy.
For the issues of high temperature performance affected by the alloying elements content in Ti-V-Cr and Ti-V-Cr alloys, the thermodynamic calculation method based on JMatPro program was applied in this study. The rese...
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As part of the 4th industrial revolution,programmable mechanical metamaterials exhibit great application potential in flexible robotics,vibration control,and impact ***,maintaining a programmed state without sustainin...
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As part of the 4th industrial revolution,programmable mechanical metamaterials exhibit great application potential in flexible robotics,vibration control,and impact ***,maintaining a programmed state without sustaining the external stimulus is often challenging and leads to additional energy *** by Rubik’s cube,we design and study an in-situ programmable and distribution-reconfigurable mechanical metamaterial(IPDR-MM).A matrix model is developed to model IPDR-MMs and describe their morphological *** on this model,the reinforcement learning method is employed to find the pathways for morphological *** find that IPDR-MMs have controllable stiffness across several orders of magnitude and a wide range of adjustable anisotropies through morphology ***,because of the independence of the directions of morphology transformation and bearing,IPDR-MMs exhibit good stability in bearing and can readily achieve high *** Rubik’s cube-inspired design concept is also instructive for other deformable structures and metamaterials,and the current version of the proposal should be sufficiently illustrative to attract and broaden interdisciplinary interests.
In this study, carbon nanotubes(CNTs)/AlSi10Mg composite parts with CNTs contents ranging from 0.0 to 2.0wt.% were successfully fabricated via laser powder bed fusion(LPBF) with laser scan speeds ranging from 900 to 1...
In this study, carbon nanotubes(CNTs)/AlSi10Mg composite parts with CNTs contents ranging from 0.0 to 2.0wt.% were successfully fabricated via laser powder bed fusion(LPBF) with laser scan speeds ranging from 900 to 1,900 mm·s-1. Uniform dispersion of CNTs in the powders can be achieved when their content is below 2.0wt.%. In the LPBF samples, the morphology of the CNTs is found to be directly related to their ***, the length of CNTs in samples prepared by LPBF increases as the CNT content increases. The length of CNTs is approximately 200-300 nm in the 1.0wt.% CNTs/AlSi10Mg composites and approximately 500-1,000 nm in the 2.0wt.% CNTs/AlSi10Mg composites. The hardness of the composites reaches its highest value of 143.3 HV when the CNTs content is 1.0wt.% and the laser scan speed is 1,300 mm·s-1. It is found that the self-lubricating properties of the CNTs improve the tribological properties of the composites. The coefficient of friction(CoF) and wear rate of the samples decrease with increasing CNT content. At a CNTs content of 2.0wt.%,the CoF and wear rate of the composite decrease by approximately 14% and 30%, respectively, compared to the unreinforced matrix. The presence of CNTs leads to a more complete and refined network microstructure within the samples. Both the CNTs and the aluminum carbide contribute to the Orowan mechanism and the Hall-Petch effect within the matrix.
With the development of the economy and the increasing demand for environmental protection,the efficient and selective recovery of Gd(Ⅲ)from actual wastewater is of critical *** this work,lanthanum-based metal-organi...
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With the development of the economy and the increasing demand for environmental protection,the efficient and selective recovery of Gd(Ⅲ)from actual wastewater is of critical *** this work,lanthanum-based metal-organic framework(LaBDC)materials were prepared by a hydrothermal method,and then polyethyleneimine(PEI)and LaBDC were combined by an impregnation method to form a novel LaBDC@xPEI *** prepared materials were characterized using Fourier transfo rm infrared spectroscopy(FTIR),X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive X-ray spectroscopy(EDX),B runauer-Emmett-Teller(BET),thermogravimetric analysis(TGA)and X-ray photoelectron spectroscopy(XPS).Experiments show that LaBDC@50%PEI has the highest adsorption capacity(181.77 mg/g)among lanthanum-based MOFs with different PEI loadings at pH=5.5,which is about 5.1 times that of bare *** adsorption isotherm analysis shows that LaBDC@50%PEI follows the Langmuir *** addition,the adsorption kinetics of LaBDC@50%PEI follows a pseudo-second-order kinetic model,indicating that the adsorption process is chemical *** is worth noting that LaBDC@50%PEI maintains good adsorption performance and stability after three recycling tests,and exhibits excellent selectivity in cation interference ***,the LaBDC@50%PEI composites possess good stability and hold great promises in rapid recovery of Gd(Ⅲ)from practical aqueous environments.
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