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.
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.
With industrial grade Al(OH)3 as raw materials, the self dispersion nanosized AlOOH crystal powder were prepared by the sol-hydrothermal method. The results of XRD and TEM show that the nanosized AlOOH could automat...
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With industrial grade Al(OH)3 as raw materials, the self dispersion nanosized AlOOH crystal powder were prepared by the sol-hydrothermal method. The results of XRD and TEM show that the nanosized AlOOH could automatically disperse to a single-dispersing state in water without surface modification, dispersant, additive and accessional conditions (ultrasonic wave dispersing, ball-mill dispersing). The application results of the product indicate that the nanosized AlOOH can be composed into a toughened nanocomposites without surface modification. Accordingly, the self dispersion characteristic and mechanism of hydrothermal crystallization and charging composite dispersion of nanosized AIOOH are found, and a new technique of preparing polymer/inorganic nanocomposites is proposed, which is called blending compositing new techniques of sol even dispersing at auasi-homogeneous phase.
(1-x)(K0.44Na0.52Li0.04)(Nb 0.84Ta0.10Sb0.06)O3-xSrTiO 3 (KNNT-ST) lead free piezoelectric ceramics have been synthesized by a solid state reaction method. The effect of SrTiO3 content on the piezoelectric properties,...
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(1-x)(K0.44Na0.52Li0.04)(Nb 0.84Ta0.10Sb0.06)O3-xSrTiO 3 (KNNT-ST) lead free piezoelectric ceramics have been synthesized by a solid state reaction method. The effect of SrTiO3 content on the piezoelectric properties, sintering behavior and microstructure of (1-x) KNNT-x ST ceramics was investigated. The experimental results showed that the addition of SrTiO3 can restrain the volatilization of Na ions and K ions and improve relative density of the samples. A morphotropic phase boundary between orthorhombic and tetragonal phases is found in the composition range of 0.03
Effect of adding up to 5wt% CaF2 on the densification and microstructural development of hot pressed aluminum nitride (AlN) was investigated. SEM investigation showed that the grain size of the sintered sample decreas...
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Effect of adding up to 5wt% CaF2 on the densification and microstructural development of hot pressed aluminum nitride (AlN) was investigated. SEM investigation showed that the grain size of the sintered sample decreases with the increasing content of CaF2. Secondary-phase evolution paths converge from CA6 to CA phase above 1650°C TEM micrographs showed that formed secondary phases could evaporate from sintered bodies at higher temperatures in the carbon-containing nitrogen atmosphere and the residuals were mainly distributed at triple grain junctions, keeping direct connections of AlN grains. Translucnet AlN ceramics were prepared using CaF 2 additive sintered at 1850°C for 5 h.
Based on the nitridation reaction of aluminum with boron nitride (BN), aluminum nitride (AlN) matrix composites were fabricated by reaction synthesis technique. The effect of the amount of Al on the microstructure and...
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Based on the nitridation reaction of aluminum with boron nitride (BN), aluminum nitride (AlN) matrix composites were fabricated by reaction synthesis technique. The effect of the amount of Al on the microstructure and properties was investigated. The bending strength, thermal conductivity and dielectric constant increase with the content of aluminum. A heat-treatment schedule was performed to investigate the effect of the microstructure on the properties. The results showed that the heat-treatment leads to the grain growth and thermal conductivity increase with the grain growth.
In this work, Fe and Si powders were used to fabricate 6.5% Si silicon steel. The mixing powder was rolled into strip and then treated at 900°C in Ar. Sn was added into the mixing powder to investigate the effect...
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In this work, Fe and Si powders were used to fabricate 6.5% Si silicon steel. The mixing powder was rolled into strip and then treated at 900°C in Ar. Sn was added into the mixing powder to investigate the effect of Sn on the sintering. The density, composition, and structure were examined. The results show that Fe almost does not react with Si at 900°C But with the addition of Sn, Fe reacts with Si to produce Fe3Si at 900°C Increasing the amount of Sn accelerates this reaction. When the amount of Sn addition is excessive, there will leave many pores in the alloy because the reaction rate is too fast to shrink. The proper amount of Sn addition can decrease the sintering temperature and shorten the sintering time.
Polycrystalline alumina was prepared at high temperature and high pressure from combustion reaction plus mechanical pressure. The defect structure in the sintered alumina was investigated by transmission electron micr...
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Polycrystalline alumina was prepared at high temperature and high pressure from combustion reaction plus mechanical pressure. The defect structure in the sintered alumina was investigated by transmission electron microscopy and a regular hexagonal dislocation network was found. Diffraction contrast technique revealed that the regular hexagonal network on the (0001) plane was composed of three dislocations with Burgers vectors: 1/3[12¯10], 1/3[2¯110] and 1/3[112¯0]. The formation process of dislocation network was discussed.
To reuse roller waste as a raw material of high performance green ceramic balls,three kinds of white alumina ceramic balls whose wear resistance were 2-3 times of the best high alumina ceramic ball with90% Al2O3 were ...
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To reuse roller waste as a raw material of high performance green ceramic balls,three kinds of white alumina ceramic balls whose wear resistance were 2-3 times of the best high alumina ceramic ball with90% Al2O3 were prepared,and the Al2O3 content of the prepared balls was 75%.It is found that the effect of calcia and magnesia on the wear resistance of ceramic balls is contrast to the accepted one: the wear rate of the ceramic balls prepared in CaO-Al2O3-SiO2 system is the lowest and the wear rate of the ceramic balls prepared in MgO-Al2O3-SiO2 is the *** main crystal phase of the ceramic ball is mullite and *** ceramic ball granular is uniform and fine with 4-5 um average *** pore diameter is about 2 *** wear way of the ceramic balls is mainly transcrystalline fracture.
This paper discusses the present status of, and future perspectives on nano Traditional Chinese medicine (TCM) by describing the concept, its methodologies, preservation, drug effect and pharmacological study. The exp...
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