SiC/Cu composites exhibit low density, low coefficient of thermal expansion and excellent mechanical properties. In this study, Zn of 2 wt. % was added as the sintering activator, and the high volume faction (60%) SiC...
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A novel kind of porous SiO2@TiO2 microspheres have been synthesized by a convenient hydrothermal method with SiO2 spheres as the core strcuture, which exhibits an enhanced degradation rate towards gaseous benzene than...
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Antimony-doped tin oxide (ATO) nanoparticles with controlled doping level were prepared by a nonaqueous solution route, using alcohol as the solvent, citric acid as an agent, tin (IV) tetrachloride as tin source and a...
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Loosely packed MoS2 nanosheets with thin carbon coating were synthesized via a facile, one-pot hydrothermal growth method. In the resulted optimal-designed nanoarchitecture, the ultrathin nanosheets, with a wall-thick...
Loosely packed MoS2 nanosheets with thin carbon coating were synthesized via a facile, one-pot hydrothermal growth method. In the resulted optimal-designed nanoarchitecture, the ultrathin nanosheets, with a wall-thickness of approximately 5-10 nm, provide large electrode-electrolyte interface, so as to facilitate faster lithium-ions intercalation and diffusion. The flexible and conductive carbon overcoats accommodate and alleviate the volume variation of the composites and thus maintain the structural and electrical integrity. In favor of the synergy and interplay of the carbon effect and intrinsic structural advantages, MoS2@C (1:2) composites with the precursor MoO3: D-glucose molar ratio of 1:2 exhibit high reversible specific capacity of 1419 mA h g-1 at 0.1 A g-1, retain 80 % of the capacity after 50 cycles, and excellent rate capability as high as 672 mA h g-1 at 10 A g-1 with almost 100 % Coulombic efficiency. The good electrochemical performance suggests that these MoS2@C composites with unique flower-like morphology give rise to high specific surface area and increased layer distance leading to the reduced diffusion path of lithium-ions and rapid electrons transport. The rational and optimal design of the MoS2@C composites with an excellent electrochemical performance in the report creates a new avenue to develop a high-performance anode material.
Multi walled carbon nanotubes decorated with ferriferrous oxide nanoparticle (MWCNTs-Fe3O4) complex was used as an effective reinforcement in the polymer composites. The MWCNTs-Fe3O4 with various grafting contents of ...
Multi walled carbon nanotubes decorated with ferriferrous oxide nanoparticle (MWCNTs-Fe3O4) complex was used as an effective reinforcement in the polymer composites. The MWCNTs-Fe3O4 with various grafting contents of Fe3O4 nanoparticles were successfully prepared by combining in situ atom transfer radical polymerization (ATRP) and coprecipitation process, which was characterized with Fourier transform infrared spectroscopy (FT-IR) and transmission electron microscope (TEM). The MWCNTs-Fe3O4 complex showed the strong magnetic response behavior, which could be easily aligned in an external magnetic field. The alignment state of MWCNTs-Fe3O4 complex could be modulated by adjusting the intensity of external magnetic field, grafting content of Fe3O4 nanoparticles and viscosity of the solvent. Moreover, with the addition of MWCNTs-Fe3O4, tensile strength and modulus of epoxy composites were enhanced by 12.3 and 10.9%, respectively, which was due to the reinforcing effect of the aligned MWCNTs-Fe3O4 within magnetic field.
The microstructures and mechanical properties of 550 MPa grade lightweight high strength thin-walled H-beam steel were experimentally studied. The experimental results show that the microstructure of the air-cooled H-...
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The microstructures and mechanical properties of 550 MPa grade lightweight high strength thin-walled H-beam steel were experimentally studied. The experimental results show that the microstructure of the air-cooled H-beam steel sample is consisted of ferrite, pearlite and a small amount of granular bainites as well as fine and dispersive V（C,N） precipitates. The microstructure of the water-cooled steel sample is consisted of ferrite and bainite as well as a small amount of fine pearlites. The microstructure of the water-cooled sample is finer than that of the air-cooled sample with the average intercept size of the surface grains reaching to 3.5 gna. The finish rolling temperature of the thin-walled high strength H-beam steel is in the range of 750 ~C-850 ~C. The lower the finish rolling temperature and the faster the cooling rate, the finer the ferrite grains, the volume fraction of bainite is increased through water cooling process. Grain refinement strengthening and precipitation strengthening are used as major strengthening means to develop 550 MPa grade lightweight high strength thin- walled H-beam steel. Vanadium partially soluted in the matrix and contributes to the solution strengthening. The 550 MPa grade high-strength thin-walled H-beam steel could be developed by direct air cooling after hot rolling to fully meet the requirements of the target properties.
Fibrinogen adsorption onto surface-attached poly(methacrylic acid) monolayers and poly(methacrylic acid)/polyethyleneimine bilayers has been investigated. The adsorbed amount of fibrinogen was found to be dependant on...
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Nb/Ta multilayer films deposited on Ti6A14V substrate with Nb and Ta monolayer thicknesses of 30 nm, 120 nm, and 240 nm were irradiated by a high current pulse electron beam （HCPEB） to prepare Nb-Ta alloyed layers. ...
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Nb/Ta multilayer films deposited on Ti6A14V substrate with Nb and Ta monolayer thicknesses of 30 nm, 120 nm, and 240 nm were irradiated by a high current pulse electron beam （HCPEB） to prepare Nb-Ta alloyed layers. The mi- crostructure and the composition of the outmost surface of melted alloyed layers were investigated using a transmission electron microscope （TEM） equipped with an X-ray energy dispersive spectrometer （EDS） attachment. The Ta content of the alloyed surface layer prepared from the monolayer of thickness 30 nm, 120 nm, and 240 nm was- 27.7 at.%, 6.37 at.%, and 0 at.%, respectively. It was found that the Ta content in the alloyed layer plays a dominant role in the microstructure of the films. The hardness and the wear rate of the alloyed layers decrease with the increasing content of Ta in the surface laver.
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