In order to improve the bioavailability, Radix salvia miltiorrhiza raw powder mixed with distilled water （5.5wt%） was ultrafinely ground to nanosize particles using HSCS pulverizer, and the dissolving-out quantity o...
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In order to improve the bioavailability, Radix salvia miltiorrhiza raw powder mixed with distilled water （5.5wt%） was ultrafinely ground to nanosize particles using HSCS pulverizer, and the dissolving-out quantity of tanshinone IIA in the filtrate that obtained from nanoparticles suspension and raw powder marinated in water for different time was determined by HPLC. The experimental results show that raw powder can be ultrafinely ground to 133.5 nm at 1500 r/min for 50 min and the molecular structure of active ingredients doesnot change, and the dissolving-out quantity of tanshinone IIA obtained from the filtrate is increased greatly from 12.77 μg/g to 54.55 μg/g.
Abstract A systematic research was performed about diffusion kinetics of adsorbing F − dissolved in water for carbonate hydroxyapatite (CHAP) from the natural hydroxyapatite which was modified by adulterating with CO ...
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Abstract A systematic research was performed about diffusion kinetics of adsorbing F − dissolved in water for carbonate hydroxyapatite (CHAP) from the natural hydroxyapatite which was modified by adulterating with CO 2 3 . The result shows that the speed of F − adsorption is controlled by membrane diffusion when F − concentration is relatively low, which is expressed by the kinetic equation of diffusion Q =0.0005( C 1 - C )( t - t 1 )+0.3967, or by vacancy diffusion when F − concentration is relatively high, which is expressed by the kinetic equation of diffusion In[ C (o, t )]=8.4718-0.5048ln t . Based on the feature of CHAP for adsorbing F − dissolved in water and its special channel of the structure of CO 2 3 - modified hydroxyapatite, models of vacancy diffusion and membrane diffusion were established.
The synergetic effects of codoped Zr4+ and F- ions within anatase hollow microspheres produced by a fluoridemediated self-transformation strategy are investigated and discussed. The concomitant participation of Fpromo...
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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）...
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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.
High temperature dielectric properties were studied in La and Nb co-doped Sr2Ta2O7system. The resistivity activation energy increases by La-doping leading to increase of resistivity. The resistivity of Sr1.98La0.02Ta2...
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High temperature dielectric properties were studied in La and Nb co-doped Sr2Ta2O7system. The resistivity activation energy increases by La-doping leading to increase of resistivity. The resistivity of Sr1.98La0.02Ta2O7is 3.65 × 107at 700°C, significantly higher when compared to the resistivity of Sr2Ta2O7(4.37 × 106)at same temperature. The Nb-doping has little influence on the structure of Sr2Ta2O7except displacements of the O ions perpendicular to the line joining the Ta and O ions. The Curie temperature was improved greatly by Nb-doping, which increase from -173°C (Sr2Ta2O7) to -11°C (Sr1.98La0.02Ta1.9Nb0.1O7).
Transparent Fe-doped In2O3 thin film was prepared by sol-gel method on (general) glass substrate. The structure, morphologies, transmission and magnetic properties of the sample have been characterized by X-ray diffra...
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Transparent Fe-doped In2O3 thin film was prepared by sol-gel method on (general) glass substrate. The structure, morphologies, transmission and magnetic properties of the sample have been characterized by X-ray diffraction, field emission scanning electron microscopy, UV-Vis spectroscopy and vibrating sample magnetometer. XRD result indicated that the sample was single cubic In2O3 phase. FE-SEM clearly showed that the film was homogenous and composed of refining grain with an average size of 14 nm. UV-Vis spectrum indicated that the transmittance of the film was higher than 80% in the visible light, and the Fe-doped In2O3 film arose the optical absorption spectrum red shift. VSM demonstrated the sample was (room temperature ferromagnetic.
The 5-axis milling processes were conducted with several uncoated WC-Co tools, which are with taper ball end mills with four flutes. There is a severe problem of high rate of tool failure, which has led to the high co...
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The 5-axis milling processes were conducted with several uncoated WC-Co tools, which are with taper ball end mills with four flutes. There is a severe problem of high rate of tool failure, which has led to the high cost and low productivity of the milling process. In order to find out the real reason, some former work, which included the tool geometry analysis, tool path and tool posture analysis, as well as the cutting force calculating, had been done. It has been found that most of the tool failures are resulted from cutting edge chipping or the workpiece material of titanium alloys attached to the tool, Meanwhile, a suddenly applied load or an abrupt unloading of the tool at the end of a cut is another important factor. Moreover, the tool materials had been analyzed, which included the element composition analysis with XRD, the microstructure analysis with SEM. XRD results indicate the cobalt at the tip of tool is less than at the shank of tool. SEM results indicate there are micro-cracks concentrated in the cutting edge area. The tool material failure mechanism will be set up based on the tool material analysis in this study.
In order to reduce the oxidizing, volatilizing and carbonizing caused by Mg element in the traditional methods for synthesizing Mg2X (X=Si, Ge, Sn) compounds, solid state reaction at low temperature was introduced, DT...
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In order to reduce the oxidizing, volatilizing and carbonizing caused by Mg element in the traditional methods for synthesizing Mg2X (X=Si, Ge, Sn) compounds, solid state reaction at low temperature was introduced, DTA, XRD, SEM, and EDS were used to characterize the powders. At the same time, the influences of parameters during the synthesisprocessing were discussed. The results suggest that the oxidation of Mg can be restrained by changing heating programs, the separation of Sn can be controlled by adjusting pre-pressure, the volatility of Mg can be made up by controlling excessive content of Mg. When the excessive content of Mg is about 0.0025 mol, the pre-pressure is about 20 MPa, the samples is kept under 823 K for 8 h, high purity Mg2Sn powders can be obtained under this experimental conditions.
In this paper the inflaming retarding effects of epoxy resins blended with basic magnesium carbonate [Mg(OH)2·4MgCO3·5H2O] were synthesized. When the add-on of basic magnesium carbonate reached 56.5%, the LO...
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In this paper the inflaming retarding effects of epoxy resins blended with basic magnesium carbonate [Mg(OH)2·4MgCO3·5H2O] were synthesized. When the add-on of basic magnesium carbonate reached 56.5%, the LOI of the epoxy resins increased to 29.7%. The flame retardant mechanisms of basic magnesium carbonate for epoxy resins was investigated by XRD, TG-DSC and SEM. Results showed that through the ways of diluting, cooling, isolating and their synergies, basic magnesium carbonate achieves the flame retarding target.
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