Formation of secondary non-Sulfide zinc ore in Cho Dien Pb - Zn deposits - Nguyen Thi LienIn the Cho Dien deposit, strong weathering process makes the upper part of ore bodies completely oxidized. Primary ore minerals are mainly sphalerite, pyrite, galena which are replaced by secondary ore minerals such as hemimorphite (calamine), smithsonite, goethite, anglesite and cerusite. Difference in geochemical behavior of lead (Pb) and z...
12 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 877 | Lượt tải: 0
The triterpenoid and steroid from the fruiting body of ganoderma applanatum (pers.) pat. in Viet Nam - Hoang Van TrungCompound 5 was obtained as white powder. The EI-MS of 5 showed a pseudomolecular ion peak at m/z 454 [M]+, combination with 1H- and 13C-NMR spectral data allowed to propose the molecular formula of C30H46O3. In its 1H-NMR spectrum, there were proton signals characteristic of three olefinic protons [ H 5.47 (1H, d, H-7); 6.91 (1H, t, H-24) and 5....
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Enhancement of li–ion battery capacity using nickel doped lifepo4 as cathode material - La Thi HangLiFePO4 and nickel doped samples were successfully synthesized using solvothermal technique. The nickel impact on LFP structure clearly exhibited by the decrease of volume and lattice cell parameter as well as suppression of some vibration bands (translation and internal modes). The capacity and voltage of doped samples enhanced significantly du...
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Tra bac activated carbon used as electrode material in aqueous supercapacitor - Van Man TranThe EDLC electrode made from Tra Bac coconut shell activated carbon exhibited a good capacitance, especially in KOH solution. The addition of acetylene black C65 enhanced capacitance due to improvement of electric conduction. The capacitance was 20 F/g at 1 A/g and 12.5 F/g at 10 A/g. The stable charge/discharge was verified that 88 % the initia...
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Application of tio2–p25 in the photodegradation of n–lauryl diethanolamine and cinnamic acid in presence of oxygenThe adsorption and photolysis of n–LDA and CA with TiO2–P25 catalyst were not substantial. The nature of reactant played a decisive role in determining the optimal reaction condition. Photodecomposition of CA occurred more hardly than n–LDA and higher catalyst concentration was needed. n–LDA with pKa = 8.7 should be photodecomposed favorably at ...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 904 | Lượt tải: 0
Effects of nd2o3 on the crystallization and properties of glass ceramic in li2o–k2o–al2o3–sio2– p2o5 systemThe effects of Nd2O3 content (0–1 wt%) on crystallization and the properties of GC derived from the system Li2O–K2O–Al2O3–SiO2–P2O5 were discussed. The results showed as follows: 1. The results of DTA showed the small variation of characteristic temperatures of glass powders, especially the melting temperature Tm. It means that the GC system can...
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Synthesis and electrochemical properties of mesoporous carbon supported well–dispersed cobalt oxides nanoparticles - Nguyen Van TuWell-dispersed cobalt oxide nanoparticles supported on mesoporous carbon CMK-3 have been synthesized successfully. The prepared composites can have as high as 15 wt% cobalt. The sample possesses a good dispersion of cobalt particles (~4 nm) and a surface area of up to 1160 m g? The electrochemical testing results suggest that the mesoporous structu...
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Effect of preparation conditions of biochar from rice straw by hydrothermal carbonization - Ngoc Bich NguyenRSM was successfully used to investigate the effects of preparation variables on the MB removal. HTC temperature was found to be the most significant effect on responses. In contrast, the RS/water ratio was insignificant on the response. The optimum BC was obtained by using HTC temperature, HTC time and RS/water ratio of 194.07 °C, 9.00 h and 5....
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Electrospray method: processing parameters influence on morphology and size of pcl particles - Linh Viet Nguyen VuThe flow rate is a main processing parameters effects morphology of electrosprayed particles. Increasing flow rate from 0.5 mL/h to 2 mL/h caused bigger electrosprayed particles size, but the aggregation happened when the flow rate increased to 4 mL/h. Furthermore, the desirable microspheres were formed using a suitable set of parameters: flow rate...
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Effects of several factors on anti–vibration ability of epdm rubber - Phan Quoc PhuThe results in this study indicated that, by the way of changing the morphology in the sample by using TEA to make the porous structure or altering the sulfur and carbon black contents to change the amount of cross-linking in the compound (the strong chemical bonds of the sulfur linkages between the chains of the rubber molecules and the strong int...
7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 939 | Lượt tải: 0
