A new ternary composite of W-SiCP/Cu(40vol%) was designed and prepared by low temperature hot-press sintering. The micro-structural characterizations were evaluated by X-ray diffraction (XRD) and scanning electron mic...
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A kind of degradable magnesium phosphate bone cement(MPBC)was fabricated by using the mixed powders of magnesium oxide(MgO),potassium dihydrogen phosphate(KH_(2)PO_(4))and calcium dihydrogen phosphate(Ca(H_(2)PO_(4))2...
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A kind of degradable magnesium phosphate bone cement(MPBC)was fabricated by using the mixed powders of magnesium oxide(MgO),potassium dihydrogen phosphate(KH_(2)PO_(4))and calcium dihydrogen phosphate(Ca(H_(2)PO_(4))2.H_(2)O).As MgKPO_(4),the main product of MgO and KH_(2)PO_(4)was alkaline,the Ca(H_(2)PO_(4))2.H_(2)Owas added to neutralize the alkali of the *** the effects of Ca(H_(2)PO_(4))2.H_(2)Oon the performance of MPBC were *** results showed that the adding of Ca(H_(2)PO_(4))2.H_(2)Oextended the setting time,which was about 6 min to 18 *** compressive strength increased first and then decreased,and maximum value reached 31.2MPa after setting for 24 h without any additional *** MPBC was degradable in Tris–HCl solution,and the extracts of the cytotoxicity assay showed that the MPBC had good biocompatibility,indicating that the MPBC had good biodegradable and biocompatible properties.
Spark plasma sintering（SPS） was used to weld the ceramics,eg,Cr3C2 and metal,Ni in this *** is found that the SPS can weld the Cr3C2 and Ni plates at lower temperatures and shorter holding time comparing with that o...
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Spark plasma sintering（SPS） was used to weld the ceramics,eg,Cr3C2 and metal,Ni in this *** is found that the SPS can weld the Cr3C2 and Ni plates at lower temperatures and shorter holding time comparing with that of hot-pressing（HP）.The binding strength was 113 MPa when the temperature was 1000 ℃ by SPS,compared with 10 MPa by HP at the same *** remarkably enhances the atom diffusion in *** analysis at different welding temperatures and holding times of SPS or HP shows that the local temperature gradient,different from the past effects of by-passing current,is the dominative mechanism of the SPS welding.
Adsorption of poly（L-lysine） on surface-attached poly（methacrylic acid） monolayers formed through in situ free radical polymerization was investigated. A strong ＂template effect＂ was observed for the adsorption ...
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Adsorption of poly（L-lysine） on surface-attached poly（methacrylic acid） monolayers formed through in situ free radical polymerization was investigated. A strong ＂template effect＂ was observed for the adsorption of poly（L-lysine） on poly（methacrylic acid） layers, which were perpendicularly grown from the surface of substrates. The adsorbed amount of poly（amino acid） increases linearly with the increase in initial layer thickness of poly（methacrylic acid） monolayers. In addition, the adsorbed poly（amino acid） is relatively stable in medium concentration of salt solution but can be completely released from the brush in high salt concentration.
LiCoO 2 is used as a cathode material for lithium-ion batteries, however, cationic/anodic-redox-induced unstable phase transitions, oxygen escape, and side reactions with electrolytes always occur when charging LiCoO ...
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LiCoO 2 is used as a cathode material for lithium-ion batteries, however, cationic/anodic-redox-induced unstable phase transitions, oxygen escape, and side reactions with electrolytes always occur when charging LiCoO 2 to voltages higher than 4.35 V, resulting in severe capacity fade. Reported here is Mg-pillared LiCoO 2 . Dopant Mg ions, serving as pillars in the Li-slab of LiCoO 2 , prevent slab sliding in a delithiated state, thereby suppressing unfavorable phase transitions. Moreover, the resulting Li-Mg mixing structure at the surface of Mg-pillared LiCoO 2 is beneficial for eliminating the cathode-electrolyte interphase overgrowth and phase transformation in the close-to-surface region. Mg-pillared LiCoO 2 exhibits a high capacity of 204 mAh g −1 at 0.2 C and an enhanced capacity retention of 84 % at 1.0 C over 100 cycles within the voltage window of 3.0–4.6 V. In contrast, pristine LiCoO 2 has a capacity retention of 14 % within the same voltage window.
Tin oxide（SnO2） and fluorine doped tin oxide（FTO） films were prepared on glass substrates by sol-gel spin-coating using SnCl4 and NH4F *** doping concentration was fixed at 4 at%and 20 at%by controlling precursor ...
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Tin oxide（SnO2） and fluorine doped tin oxide（FTO） films were prepared on glass substrates by sol-gel spin-coating using SnCl4 and NH4F *** doping concentration was fixed at 4 at%and 20 at%by controlling precursor sol *** exhibited the tetragonal rutile-type crystal structure regardless of fluorine *** and highly transparent FTO films,with more than 85%of optical transmittance,were obtained by annealing at 600℃.Florine doping of films was verified by analyzing the valence band region obtained by *** was found that the fluorine doping affects the shape of valence band of SnO2 *** addition,it was observed that the band gap of SnO2 is reduced as well as the Fermi level is upward shifted by the effect of fluorine doping.
A heightened understanding of nucleation and growth mechanisms is paramount if effective solution processing of organic-inorganic perovskite thin-films for optoelectronic applications is to be achieved. Many fabri- ca...
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A heightened understanding of nucleation and growth mechanisms is paramount if effective solution processing of organic-inorganic perovskite thin-films for optoelectronic applications is to be achieved. Many fabri- cation techniques have been utilized previously to develop high-performance perovskite layers but there remains an absence of a unifying model that describes accurately the formation of these materials from solution. The present study provides a thorough analysis of nucleation and growth kinetics underpinning the development of hybrid organic-in- organic perovskite thin-films. Through precise control of the perovskite growth conditions the spacing of heteroge- neous nucleation sites was varied successfully from several hundred nanometers to several hundred microns. The crystalline regions surrounding these nuclei were found to comprise clusters of highly-oriented crystal domains exceed- ing 100 pm in diameter. However, no beneficial correlation was found between the size of these well-oriented grain-clus- ters and the optoelectronic performance. The formation of the perovskite microstructure features characteristics of both classical and non-classical growth mechanisms. The insights into perovskite thin-film growth developed by the present study provide clear implications for the development of future hybrid perovskite microstructures.
Hierarchical urchin-like gamma-Al2O3 hollow microspheres were prepared by a hydrothermal method followed by a calcination process using Al(NO3)(3)center dot 9H(2)O as aluminum source, NH3 center dot H2O as precipitati...
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Hierarchical urchin-like gamma-Al2O3 hollow microspheres were prepared by a hydrothermal method followed by a calcination process using Al(NO3)(3)center dot 9H(2)O as aluminum source, NH3 center dot H2O as precipitating agent, and P123 as structure-directing agent (SDA). The obtained samples were investigated using X-ray diffraction (XRD), filed emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and N-2 adsorption/desorption. The influences of P123 concentration, acidic condition, and hydrothermal time on the morphology of product were discussed. P123 has a great influence on ruling the oriented attachment of nanowires and stabilizing the superstructure in the self-assembly process. The 3D urchin-like hollow microspheres have a surface area of 210.2 m(2)/g and the average pore size is 11.42 nm, which have widely potential application such as catalyst, adsorption, and separation.
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