In response to the growing demand for energy efficiency,safety,and lightweight designs in new energy vehicles,this study addresses the challenge of balancing strength and toughness in ultra-high strength steel(UHSS)co...
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In response to the growing demand for energy efficiency,safety,and lightweight designs in new energy vehicles,this study addresses the challenge of balancing strength and toughness in ultra-high strength steel(UHSS)components produced by hot *** innovative hot stamping process based on a martensite-bainite(M-B)complex-phase microstructure was proposed to enhance the strength and toughness of *** microstructural evolution of the M-B complexphase during the hot stamping process was investigated using commercial B1800HS *** a microstructure consisting of 87.4.%martensite,8.7%lower bainite,and 3.9%film-like retained austenite by volume fraction,the steel achieved a tensile strength of 1944 MPa,total elongation of 9.66%,and impact energy of 25.8 *** with conventional hot stamping,the strength of the material showed only a slight improvement,whereas elongation and impact energy were enhanced by approximately 53%and 32%,respectively.A quantitative relationship among process parameters,resulting microstructure,and mechanical properties was *** between strength and toughness was observed when the low bainite volume fraction ranged from 5.06%to 8.73%.The toughening mechanisms are attributed to the refinement of martensite lath bundles(width of 202 nm)facilitated by bainite formation,the increase in high-angle grain boundaries,and the presence of nanoscale retained austenite(width of 80 nm)between the ***,the refinement of grains and the formation of nanoscale(Nb,Ti)C precipitates(diameter of 17 nm)further contributed to the overall *** developed M-B complexphase process,which involves medium-temperature slow cooling followed by rapid low-temperature quenching,provides an optimal combination of strength and toughness for a wide range of applications.
We synthesized BiVO_(4)mesocrystals with ordered assembly structure,and studied the structural order and the relationship between the photodegradation of Rhodamine *** nanoparticles(NPs)were successfully loaded onto M...
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We synthesized BiVO_(4)mesocrystals with ordered assembly structure,and studied the structural order and the relationship between the photodegradation of Rhodamine *** nanoparticles(NPs)were successfully loaded onto Meso-BiVO_(4)by light-assisted induction,and Cd nanoparticles were further selected to be deposited on Au nanoparticles to form Z-scheme photocatalyst Meso-BiVO_(4)-Au-CdS *** try and propose to analyze its ordered assembly structure by XRD for the first *** results show that Meso-BiVO_(4)is a mesocrystal with highly exposed(001)plane and directional assembly *** charge separation efficiency of all samples was studied by PL *** results show that the Z-scheme Meso-BiVO_(4)-Au-CdS can promote the charge separation and obtain the best carrier separation ***,it has the best photocatalytic activity in the experiment of photocatalytic degradation of rhodamine *** main active species in the degradation process were confirmed by free radical trapping experiment,and the degradation mechanism was put forward.
Under the vision of 'carbon peaking and carbon neutrality',the global energy system is facing a deep *** a clean energy with the potential to achieve zero carbon emissions,hydrogen energy will undoubtedly play...
Under the vision of 'carbon peaking and carbon neutrality',the global energy system is facing a deep *** a clean energy with the potential to achieve zero carbon emissions,hydrogen energy will undoubtedly play an important ***-energy-driven photo catalytic reactions can decompose water to produce hydrogen and reduce carbon dioxide to produce solar fuels.
A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial ***-...
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A novel strategy was developed to prepare the methacrylic gelatin-dopamine(GelMA-DA)/Ag nanoparticles(NPs)/graphene oxide(GO) composite hydrogels with good biocompatibility,mechanical properties,and antibacterial ***-inspired DA was utilized to modify the GelMA molecules,which imparts good adhesive performance to the ***,interfacial enhancer,not only improves mechanical properties of the hydrogels,but also provides anchor sites for loading Ag NPs through numerous oxygencontaining functional groups on the *** experimental results show that the GelMA/Ag NPs/GO hydrogels have good biocompatibility,and exhibit a swelling rate of 202±16%,the lap shear strength of 147±17 kPa,and compressive modulus of 136±53 kPa,in the case of the Ag NPs/GO content of 2 mg/*** activity of the hydrogels against both gram-negative and gram-positive bacteria is dependent on the Ag NPs/GO content derived from the release of Ag^(+).Furthermore,the GelMA/Ag NPs/GO hydrogels possess good adhesive ability,which is resistant to highly twisted state when stuck on the surface of *** results demonstrate promising potential of the GelMA-DA/Ag NPs/GO hydrogels as wound dressings for biomedical applications in clinical and emergent treatment.
Lithium-rich layered cathode material(LLM)can meet the requirement of power lithium-ion energy storage devices due to the great energy ***,the de/intercalation of Li+will cause the irreversible loss of lattice oxygen ...
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Lithium-rich layered cathode material(LLM)can meet the requirement of power lithium-ion energy storage devices due to the great energy ***,the de/intercalation of Li+will cause the irreversible loss of lattice oxygen and trigger transition metal(TM)ions migrate to Li+vacancies,resulting in capacity *** we brought Ti4+in substitution of TM ions in Li_(1.2)Mn_(0.54)Ni_(0.13)Co_(0.13)O_(2),which could stabilize structure and expand the layer spacing of ***,optimized Ti-substitution can regulate the anions and cations of LLM,enhance the interaction with lattice oxygen,increase Ni^(3+) and Co^(3+),and improve Mn^(4+) coordination,improving reversibility of oxygen redox activation,maintaining the stable framework and facilitating the Li^(+) ***,we found 5%Ti-substitution sample delivered a high discharge capacity of 244.2 mAh/g at 50 mA/g,an improved cycling stability to 87.3%after 100 cycles and enhanced rate *** Ti-substitution gives a new pathway to achieve high reversible cycle retention for LLMs.
Half Heusler materials exhibit excellent thermoelectric and mechanical properties,rendering them potential candidates for advanced thermoelectric ***,the developments on interrelated devices are impeded by their inher...
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Half Heusler materials exhibit excellent thermoelectric and mechanical properties,rendering them potential candidates for advanced thermoelectric ***,the developments on interrelated devices are impeded by their inherent brittleness and limited ***,it exists the potential ductility on half Heusler materials with face-centered cubic sub-lattices through the expectation of the occurrence of shear-induced‘catching bonds’which can result in excellent ductility on other face-centered cubic materials.
The wetting behavior of molten Cu on the B_(4)C-xTiB_(2)ceramic composites was investigated in this *** results show that the contact angle of molten Cu alloy on B_(4)C-TiB_(2)ceramic composites is linear with the com...
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The wetting behavior of molten Cu on the B_(4)C-xTiB_(2)ceramic composites was investigated in this *** results show that the contact angle of molten Cu alloy on B_(4)C-TiB_(2)ceramic composites is linear with the composition rate of TiB_(2)or B_(4)C while the temperature is in the range of 1300 to 1350℃,consistent with the expectation of the commonly used theoretical ***,a nonlinear relationship between the contact angle and the composition rate unexpectedly occurred at temperatures ranging from 1400 to 1500℃.The big difference of the contact angles between the molten metal and the components in the composites was found to be the key *** result identifies that the commonly used theoretical method only works at a limited difference of the contact angle of the liquid on the different phases in the composites,and fails at a big difference.
Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and t...
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Using a titration setup to accurately control the reaction conditions and in situ monitor the reaction,we showed that fluoride exhibited negligible effects on the ion association process of calcium and phosphate and the formation of ACP nanospheres in a buffer solution with constant ionic ***,the stability of ACP increased with increasing fluoride concentration,which was ascribed to the inhibitory effect of fluoride on the aggregation of ACP nanospheres and the nucleation of nanocrystals on the surface of ACP ***,fluoride could inhibit the lateral growth of HAP nanosheets and promote the formation of rod-like *** results further improve our understanding of the crystallization pathway of HAP crystals and the regulatory effects of fluoride.
To achieve high microwave permeability in wide-band for the micron-thick magnetic films,[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer structure was proposed by co-sputtering Fe and FeNi to form the magnetic layers and Cr to f...
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To achieve high microwave permeability in wide-band for the micron-thick magnetic films,[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer structure was proposed by co-sputtering Fe and FeNi to form the magnetic layers and Cr to form the *** multilayer structure contributes to the high permeability by reducing the coercivity and diminishing out-of-plane *** maximum imaginary permeability of[Fe-Fe_(20)Ni_(80)/Cr]_(n) multilayer film reaches a large value of 800 at 0.52 GHz even though its overall thickness exceeds 1μ***,the magnetic resonance frequency of the multilayer film can be modulated from 0.52 to 1.35 GHz by adjusting the sputtering power of Fe from 0 to 86 W,and its bandwidth for μ’’>200(Δf) is as large as 2.0 *** desirable broad Δf of magnetic permeability,which can be well fitted by the Landau-Lifshitz-Gilbert equations,is due to dual magnetic resonances originated from double magnetic phases of Fe and FeNi that are of different saturation *** micron-thick multilayer films with high permeability in extended waveband are promising candidate for electromagnetic noise suppression application.
Self-reconstruction of catalysts during oxygen evolution reaction(OER)is crucial for the development of energy conversion ***,the relationship between the specific atomic structure of pre-catalysts and their electroca...
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Self-reconstruction of catalysts during oxygen evolution reaction(OER)is crucial for the development of energy conversion ***,the relationship between the specific atomic structure of pre-catalysts and their electrocatalytic behavior after reconstruction via dual-ion leaching has not been extensively *** this work,we design a highly effective non-noble metal OER catalyst with heterointerface through continuous self-reconstruction of Co_(2)(OH)_(3)Cl@NiMoO_(4)as pre-catalyst by a straightforward dual-ion(***_(4)^(2-)and Cl^(-))***-situ Raman and in-situ Fourier transform infrared(FT-IR)spectroscopy have precisely identified the progressive phase transformation of the pre-catalyst during self-reconstruction,which results in a stable heterojunction of CoOOH and NiOOH(CoOOH@NiOOH).Further calculations based on density functional theory(DFT)of CoOOH@NiOOH evident that more electrons will be aggregated in the Fermi level of ***,Gibbs free energy(ΔG)for different OER steps of CoOOH@NiOOH exhibit lower energy costs of all intermediates,implying the well catalytic ***,the catalyst derived from dual-ion leaching displays outstanding OER performance,characterized by an overpotential of 275 mV at a current density of 10 mA·cm^(-2)and exceptional stability over 12 h *** work successfully paves a way of finding high-performance OER catalysts based on non-noble metal through dual-ion leaching during self-reconstruction.
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