In order to improve efficiency and reduce costs, four machine learning models were established for the design of metastable β titanium alloys, including the Adaboost model, the LightGBM model, the Voting model, and t...
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In order to improve efficiency and reduce costs, four machine learning models were established for the design of metastable β titanium alloys, including the Adaboost model, the LightGBM model, the Voting model, and the Stacking model. The accuracy of these models was evaluated, and all models exhibited excellent accuracy for tensile strength, yield strength, and elongation. The values of R-squared coefficients（R2） all greater than *** them, the LightGBM model showed the highest accuracy, with relatively smallest values of mean absolute error（MAE） and root mean square error（RMSE） and relatively largest value of R2. To further verify the accuracy of the model, a metastable β titanium alloy Ti-5.5Cr-5Al-4Mo-3Nb-2Zr was designed by the LightGBM model. The predicted values of the alloy's tensile strength, yield strength, and elongation under three heat treatment processes were in high agreement with the experimental values. The alloy exhibited optimal strength-plasticity matching after undergoing a solution treatment at 850°C for 0.5 h, followed by aging at 650°C for 8 h, with a tensile strength of 1317 MPa, an elongation of 11.17 %, and a strength-plasticity product of 14.711 GPa·%.
In this work,Ag/Ag_(2)Se composite films with excellent thermoelectric(TE)properties and flexibility are prepared based on a simple one-pot *** adjusting the nominal ratios of Ag/Se,an optimal Ag/Ag_(2)Se composite fi...
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In this work,Ag/Ag_(2)Se composite films with excellent thermoelectric(TE)properties and flexibility are prepared based on a simple one-pot *** adjusting the nominal ratios of Ag/Se,an optimal Ag/Ag_(2)Se composite film shows a large power factor of~2275 μW m^(-1) K^(-2) at 300 *** an outstand-ing TE performance of the composite film is due to the unique microstructure and the synergistic effect between the Ag and Ag_(2)***,the composite film also shows outstanding flexibility(~91.8%of the initial electrical conductivity is maintained,and the S is unchanged after 1500 bending cycles with a bending radius of 4 mm).Furthermore,a 4-leg flexible TE generator assembled with the optimal film produces a voltage of 14.06 mV and 4.96 μW at a temperature difference of 30.4 *** work provides a new inspiration for the preparation of flexible Ag_(2)Se-based films with excellent TE performance near room temperature.
Copper,one of the most frequently utilized non-ferrous metals,finds extensive applications in the elec-trical industry,mechanical engineering,construction industry,and arm ***-term exposure to corrosive environments i...
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Copper,one of the most frequently utilized non-ferrous metals,finds extensive applications in the elec-trical industry,mechanical engineering,construction industry,and arm ***-term exposure to corrosive environments including moisture,sulfur,chlorine,and microbes induces corrosion,a signifi-cant factor contributing to material ***,numerous scientific endeavors have been directed towards the prevention of copper ***,coating copper with innovative materials like graphene,boron nitride,and various conductive polymers has proven effective in thwarting ***,the introduction of new organic compounds,including azole derivatives,amino acids,and N-heterocyclic carbenes,has bolstered the eco-friendliness and efficiency of corrosion inhibitors and molecular passivation ***,these approaches have been extensively investigated for their efficacy in antioxidation of copper *** study provides a comprehensive review of the latest advancements in protective technologies,such as anti-corrosion coatings,corrosion inhibitors,and molecular passivation layers,aimed at countering copper corrosion under aggressive conditions.
As the main limiting step of overall water splitting,oxygen evolution reaction(OER)is urgent to be enhanced by developing efficient catalysts to promote the process of electrolytic *** on theoretical analysis,the Ni-m...
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As the main limiting step of overall water splitting,oxygen evolution reaction(OER)is urgent to be enhanced by developing efficient catalysts to promote the process of electrolytic *** on theoretical analysis,the Ni-metal-organic framework(Ni-MOF)and NiFe-layered double hydroxide(NiFe-LDH)(NiFe-LDH/MOF)heterostructure can optimize the energy barrier of the OER process and decrease the adsorption energy of oxygen-containing intermediates,effectively accelerating the OER ***,layered NiFe-LDH/MOF heterostructures are in situ constructed through a facile two-step reaction process,with substantial oxygen defects and lattice defects that further improve the catalytic *** a result,only 208 and 275 mV OER overpotentials are needed for NiFe-LDH/MOF to drive the current densities of 20 and 100 mA·cm^(-2)in 1 M KOH solutions,and even maintain catalytic stability of 100 h at 20 mA·cm^(-2).When applied to seawater oxidation,only 235 and 307 mV OER overpotentials are required to achieve the current densities of 20 and 100 mA·cm^(-2),respectively,with almost no attenuation for 100 h stability test at 20 mA·cm^(-2),all better than commercial RuO_(2).This work provides the theoretical and experimental basis and a new idea for efficiently driving fresh water and seawater cracking by heterostructure and defect coupling design toward catalysts.
作者：
Weifei HuYuanyuan LiJinping LiuSchool of Chemistry
Chemical Engineering and Life Science and State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070China School of Integrated Circuits
Huazhong University of Science and TechnologyWuhan 430074China
A commentary on pressure-induced pre-lithiation towards Si anodes in allsolid-state Li-ion batteries(ASSLIBs)using sulfide electrolytes(SEs)is ***,feasible pre-lithiation technologies for Si anodes in SE-based ASSLIBs...
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A commentary on pressure-induced pre-lithiation towards Si anodes in allsolid-state Li-ion batteries(ASSLIBs)using sulfide electrolytes(SEs)is ***,feasible pre-lithiation technologies for Si anodes in SE-based ASSLIBs especially the significant pressure-induced pre-lithiation strategies are briefly ***,a recent achievement by Meng et *** this field is elaborated in ***,the significance of Meng’s work is discussed.
Chronic diabetic wounds are the most common complication for diabetic *** to high oxidative stress levels affecting the entire healing process,treating diabetic wounds remains a ***,we present a strategy for continuou...
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Chronic diabetic wounds are the most common complication for diabetic *** to high oxidative stress levels affecting the entire healing process,treating diabetic wounds remains a ***,we present a strategy for continuously regulating oxidative stress microenvironment by the catalyst-like magnesium-gallate metal-organic framework(Mg-GA MOF)and developing sprayable hydrogel dressing with sodium alginate/chitosan quaternary ammonium salts to treat diabetic *** quaternary ammonium salts with antibacterial properties can prevent bacterial *** continuous release of gallic acid(GA)effectively eliminates reactive oxygen species(ROS),reduces oxidative stress,and accelerates the polarization of M1-type macrophages to M2-type,shortening the transition between inflammation and proliferative phase and maintaining redox ***,magnesium ions adjuvant therapy promotes vascular regeneration and neuronal formation by activating the expression of vascular-associated *** hydrogel dressings with antibacterial,antioxidant,and inflammatory regulation rapidly repair diabetic wounds by promoting neurovascular network reconstruction and accelerating re-epithelialization and collagen *** study confirms the feasibility of catalyst-like MOF-contained sprayable hydrogel to regulate the microenvironment continuously and provides guidance for developing the next generation of non-drug diabetes dressings.
Nano-structured silicon(Si)has demonstrated high capacity for lithium storage;however,it suffers from unsatisfactory cycling stability caused by large volume change and poor interface ***,it is very important to const...
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Nano-structured silicon(Si)has demonstrated high capacity for lithium storage;however,it suffers from unsatisfactory cycling stability caused by large volume change and poor interface ***,it is very important to construct functional coatings on nano-structured Si to buffer the volume change and improve the interface ***,we successfully construct V_(2)O_(3) and carbon(C)dual-layer coatings on Si nanoparticles with ultrathin and uniform thickness using a facile spray drying and chemical vapour deposition *** as-prepared Si@V_(2)O_(3)@C manifests a high specific capacity of 2230 mAh g^(-1) after 100 cycles under the current density of 200 mA g^(-1),showing its promising application prospect in lithium *** situ electrochemical impedance spectroscopy(EIS)results at different lithiation states and different cycles show a more stable interface resistance of Si@V_(2)O_(3)@C than pristine *** V_(2)O_(3) and C dual coating layers not only ensure the Si nanoparticles with high structural stability by buffering volume expansion and preventing electrolyte penetration,but also guarantee a superior electron transport rate because of the metallic V_(2)O_(3) as well as the highly conductive carbon layers.
A series of spinel-type Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)(MgAlON:xMn^(2+))phosphors were synthesized by the solid-state reaction *** transparent ceramic phosphors were fabricated by pressureless sintering ...
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A series of spinel-type Mg_(0.25-x)Al_(2.57)O_(3.79)N_(0.21):xMn^(2+)(MgAlON:xMn^(2+))phosphors were synthesized by the solid-state reaction *** transparent ceramic phosphors were fabricated by pressureless sintering followed by hot-isostatic pressing(HIP).The crystal structure,luminescence and mechanical properties of the samples were systematically *** transparent ceramic phosphors with tetrahedrally coordinated Mn^(2+)show strong green emission centered around 515 nm under blue light *** the Mn^(2+)concentration increases,the crystal lattice expands slightly,resulting in a variation of crystal field and a slight red-shift of green emission *** weak absorption peaks in the transmittance spectra originate from the spin-forbidden ^(4)T_(1)(^(4)G)→^(6)A_(1) transition of Mn^(2+).The decay time was found to decrease from 5.66 to 5.16 ms with the Mn^(2+)*** present study contributes to the systematic understanding of crystal structure and properties of MgAlON:xMn^(2+)green-emitting transparent ceramic phosphor which has a potential application in high-power light-emitting diodes.
Achieving the strength-ductility synergy in Mg alloys is a gigantic challenge,especially in rare-earth-free Mg *** this study,a new Mg-Sn-Zn-Zr alloy with high ultimate tensile strength(~284-326 MPa)without sacrificin...
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Achieving the strength-ductility synergy in Mg alloys is a gigantic challenge,especially in rare-earth-free Mg *** this study,a new Mg-Sn-Zn-Zr alloy with high ultimate tensile strength(~284-326 MPa)without sacrificing elongation-to-failure(~22.1-27.6%)was developed by utilizing casting,pre-treatment and hot *** random rather than basal texture is observed both in as-cast and pre-treatment ***,the strong texture is effectively weakened via hot extrusion whilst remaining *** importantly,after hot extrusion,the grain sizes of as-cast and pre-treatment samples were significantly refined down to about 10μ*** of as-extruded microstructures of the alloy reveals that the grain refinement is highly associated with the particle stimulated nucleation(PSN)and continuous/discontinuous dynamic recrystallization(C/DDRX)***,the results suggest that the combination of pre-treatment and hot extrusion not only promotes multiplication of geometrically-necessary dislocations(GNDs)but enhances dynamic precipitation,which boosts the formation of fine and homogenous *** on the results of X-ray diffraction(XRD),transmission electron microscope(TEM)and selected area electron diffraction(SAED),the precipitates are Mg_(2)Sn ***,the main orientation relationship identified by high resolution TEM(HRTEM)between Mg_(2)Sn phases andα-Mg matrix could be described as(111)Mg_(2)Snor(220)Mg_(2)Sn∥(0001)Mgwith a coherent *** refined grains size,ultra-fine precipitates and high density of GNDs would substantially contribute to the enhancement of the strength and the corresponding contributions are calculated to be~183-185 MPa,~30.9-38 MPa and~14.2-31.7 MPa,***,texture weakening or randomizing,grain refinement and coherent interfaces are mainly responsible for the high *** current study can provide beneficial insights into the development of high-performance rare-earth-
Exploring wide voltage window materials is not only an available measure to enhance the energy density of hybrid supercapacitor(HSCs),but also avoids the dynamic mismatch caused by different energy storage mechanisms ...
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Exploring wide voltage window materials is not only an available measure to enhance the energy density of hybrid supercapacitor(HSCs),but also avoids the dynamic mismatch caused by different energy storage mechanisms of two electrodes in assembled symmetrical ***,there are few reports about the wide potential window materials except Bi_(2)O_(3)and VO_(2).Therefore,the MnF_(2)synthesized by solvothermal reaction was served as the electrode for *** MnF_(2)exhibited electrochemical activity in alkaline solution in three-electrode system,especially with a wide potential window from-0.8 to+0.5 V in 2 mol·L^(-1)***,the assembled MnF_(2)//MnF_(2)symmetrical HSC had a potential window of 1.5 V,and it exhibited outstanding long-cycle ***,when MnF_(2)was taken as the negative and positive respectively,the potential windows of asymmetric devices CoMoO_(4)//MnF_(2)and MnF_(2)//Activated Carbon(AC)could reach 1.3 and 1.45 V,respectively,showing excellent cycle *** work shows that MnF_(2)material has great research value in HSC,and provides a new research direction for developing high-performance devices.
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