Al12Si3.75Ge0.25O26 ceramic powder was prepared by sol-gel method using Al（NO3）3,Si（OC2H5）4 and Cl3GeCH2-CH2COOH as *** structural formation of Al12Si3.75Ge0.25O26 ceramic powder was analyzed by *** reduction by f...
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Al12Si3.75Ge0.25O26 ceramic powder was prepared by sol-gel method using Al（NO3）3,Si（OC2H5）4 and Cl3GeCH2-CH2COOH as *** structural formation of Al12Si3.75Ge0.25O26 ceramic powder was analyzed by *** reduction by flowing H2/Ar mixture gas,strong room temperature photoluminescence （PL） can be observed at 565 nm,613 nm,682 nm,731 nm and 777 nm,*** PL intensity scarcely depends on the reduction temperature and duration,while the sample reduced at 500 ℃ for A^3 hours has the highest PL *** and after reduction at 500 ℃,the volume of unit cell of mullite solid solution decreases to 0.4699 *** on the analysis of XPS and Raman spectra,it can be approved that the PL phenomenon at room temperature is caused by the embedded Ge nanoparticles with the average size of about 1.95 nm.
High-purity Ti2AlN ceramic was prepared at 1300 ℃ by hot pressing(HP)of Ti/Al/TiN powders in stoichiometric *** sintered product was characterized using X-ray diffraction(XRD)and MDI Jade 5.0 software(materials Data ...
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High-purity Ti2AlN ceramic was prepared at 1300 ℃ by hot pressing(HP)of Ti/Al/TiN powders in stoichiometric *** sintered product was characterized using X-ray diffraction(XRD)and MDI Jade 5.0 software(materials Data Inc,Liverpool,CA).Scanning electron microscopy(SEM)and electron probe micro-analysis(EPMA)coupled with energy-dispersive spectroscopy(EDS)were utilized to investigate the morphology *** results show that Ti2AlN phase is well-developed with a close and lamellar *** grains are plate-like with the size of 3-5 μm,thickness of 8-10 μm and elongated *** density of Ti2AlN is measured to be 4.22 g/cm3,which reaches 97.9% of its theory *** distribution of Ti2AlN grains is homogeneous.
To obtain homogenous layered oxide Li（Co1/3Ni1/3Mn1/3）O2 as a lithium insertion positive electrode material, the sol-gel process using citric acid as a chelating agent was applied. The material Li（Co1/3Ni1/3Mn1/3）...
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To obtain homogenous layered oxide Li（Co1/3Ni1/3Mn1/3）O2 as a lithium insertion positive electrode material, the sol-gel process using citric acid as a chelating agent was applied. The material Li（Co1/3Ni1/3Mn1/3）O2 was synthesized at different calcination temperatures. XRD experiment indicated that the layered Li（Co1/3Ni1/3Mn1/3）O2 material could be synthesized at a lower temperature of 800℃, and the oxidation state of Co, Ni, and Mn in the cathode confirmed by XPS were ＋3, ＋2, and ＋4, respectively. SEM observations showed that the synthesized material could form homogenous particle morphology with the particle size of about 200 nm. In spite of different calcination temperatures, the charge-discharge curves of all the samples for the initial cycle were similar, and the cathode synthesized at 900℃ showed a small irreversible capacity loss of 11.24% and a high discharge capacity of 212.2 mAh·g^-1 in the voltage range of 2.9-4.6 V.
The structure and properties of Mg-doped SrBi4Ti4O15（SBT） were dicussed. Mg substitution into SBT had two possibilities states with the dopant amount variety. Mg cation substituted mostly into Sr^2＋ and the amount ...
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The structure and properties of Mg-doped SrBi4Ti4O15（SBT） were dicussed. Mg substitution into SBT had two possibilities states with the dopant amount variety. Mg cation substituted mostly into Sr^2＋ and the amount proportion was 68.11%.Mg ion will substitute into Ti ion site in perovskite layer when the doping amount increases. Polarization increases sharply when x=0.1 and then decreases becauses of the domain pinning. The Curie temperature of Mg-doped SBT is about 300 ℃ and there is a broad diffuse phase transition near Tc with a flat peak near the Ta of SBT.
Amino-terminated polyethers and amino-terminated polyurethane were used as curing agent to cure the epoxy resin together and get a series of cured products. The damping properties of the composites were studied by DMA...
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Amino-terminated polyethers and amino-terminated polyurethane were used as curing agent to cure the epoxy resin together and get a series of cured products. The damping properties of the composites were studied by DMA test at different measurement frequencies. Damping mechanical tests show that the flexible epoxy resin has higher loss factor than common epoxy. The highest loss factor reaches 1.57. Also the height and position of loss factor peak of the flexible epoxy resin varies by changing the content of amino-terminated polyethers. Results shows that the flexible epoxy resin can be used as damping polymer materials at room temperature or in common frequency range.
Ti3SiC2/TiB2 composite was successfully obtained by hot pressing Ti/TiC/Si/B4C power *** fraction of TiB2 in Ti3SiC2/TiB2 composite can not exceed 10%.Incorporation of excessive TiB2 will affect the reactions *** and ...
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Ti3SiC2/TiB2 composite was successfully obtained by hot pressing Ti/TiC/Si/B4C power *** fraction of TiB2 in Ti3SiC2/TiB2 composite can not exceed 10%.Incorporation of excessive TiB2 will affect the reactions *** and Ti5Si3 were two important intermediate phases during the whole *** microstructure characteristics of the Ti3SiC2/TiB2 composites were analyzed using scanning electron microscopy （SEM） and transmission electron microscopy （TEM）.The experimental results show that the grains of Ti3SiC2/TiB2 composite are structured in a layered form,and the formation of TiB2 particles as reinforcements with elongated or equiaxed shape distributes in Ti3SiC2 matrix.
It is very difficult to prepare full-densified aluminum nitride-boron nitride(AIN/BN)composite ceramics with homogeneous microstructure and high thermal *** plasma sintering(SPS)was used to fully densify the AIN/BN co...
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It is very difficult to prepare full-densified aluminum nitride-boron nitride(AIN/BN)composite ceramics with homogeneous microstructure and high thermal *** plasma sintering(SPS)was used to fully densify the AIN/BN composites in this ***,mechanical properties and thermal conductivity of the SPS sintered AIN/BN composites with 5-30 vol% BN were *** results show that the microstructure of composites is fine and homogenous,and the AIN/BN composites exhibit high mechanical *** promote the growth of AIN grains and modify the distribution of grain boundary in AIN/BN composites,a heat treating methodology was introduced through gas pressure sintering(GPS).This processing was significantly beneficial to enhancing the thermal conductivity of the *** thermal conductivity of AIN/BN composites with 5-30 vol% BN reached 60 W/m K after the samples were treated by GPS.
The etch damage in integrated ferroelectric capacitors side wall fabricated by the typical integrated process （TIP- FeCAP） and the innovated integrated process （IIP-FeCAP） are investigated by piezoresponse force m...
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The etch damage in integrated ferroelectric capacitors side wall fabricated by the typical integrated process （TIP- FeCAP） and the innovated integrated process （IIP-FeCAP） are investigated by piezoresponse force microscopy （PFM）. The IIP-FeCAP side wall exhibits fine and dear nanoscale domain images and the same piezoresponse signal as the thin film, and the domains can also be easily switched by an external voltage. In the TIP-FeCAP side wall, owing to the effect of etch damage, the very weak piezoresponse signal and some discrete domains can be observed, and the discrete domains cannot be switched by the applied 9 V and -9 V dc voltage. The PFM results reflect the etch damage in the integrated ferroelectric capacitors and also suggest that the PFM can be used as an efficacious tools to evaluate the etch damage at nanoscale and spatial variations.
Hydroxyapatite whiskers are used as reinforcement for biomaterials because of their needlelike morphology and strong strength of single crystal. HAP nanoparitcles are used in drug delivery system, protein separation a...
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Hydroxyapatite whiskers are used as reinforcement for biomaterials because of their needlelike morphology and strong strength of single crystal. HAP nanoparitcles are used in drug delivery system, protein separation and anticancer drug besides their implant applications. Many new properties arise from nanoeffects while nanoeffects come from specialty of nanostructure. The Ca（NO3）2·4H2O and （NH4）2HPO4 were used as starting reagents for preparation of HAP whiskers and nanoparticles. The whiskers are 100-200 μm long while nanoparticles are 30-80 nm in size. XRD is applied to characterize the lattice parameter difference of whisker and nanoparticle. Compared with those of HAP whiskers, the a-axis and b-axis of HAP nanocrystals are shortened while the c-axis is elongated. That makes nanoparticles capable of their non-needle-like morphology, higher reaction activity and special bioeffects.
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