Journal of Science and Technology
URI vĩnh viễn cho bộ sưu tập này
Duyệt qua
Đang duyệt Journal of Science and Technology theo Tác giả
Đang hiển thị 1 - 4 trong tổng số 4
Kết quả mỗi trang
Tùy chọn sắp xếp
- Tài liệuEnhanced adsorption of methylene blue onto graphene oxide-doped XFe2O4 (X 5Co, Mn, Ni) nanocomposites: kinetic, isothermal, thermodynamicand recyclability studies(Trường Đại học Nguyễn Tất Thành (Tạp chí Khoa học công nghệ NTT), 2017-10-30) Bach, Long Giang; Tran, Van Thuan; Nguyen, Duy Trinh; Pham, Van Thinh; Do, Sy TrungAbstract The nanocomposites XFe2O4/GO with various metal sites (X = Co, Mn, and Ni) were successfully synthesized via the polymerized complex method. The XFe2O4/GO family was characterized using X-Ray diffraction analysis, scanning electron microscopy (SEM), and a vibrating sample magnetometer. We also investigated the effect of three fundamental parameters (initial concentration, dosage, and pH) on the removal of methylene blue using the response surface methodology. A high F value, very low P value (\ 0.00001), a non-significant lack of fit, and the determination coefficient (R2 [ 0.95) demonstrated a strong corre- lation between experimental and predicted values of the responses. The predicted optimal conditions for maximum removal efficiency were easily determined to adhere to the following trend for actual test experiments: MnFe2O4/GO (60.1%) \ CoFe2O4/GO (80.3%) \ NiFe2O4/GO (87.7%).
- Tài liệuPreparation and Characterization of Advanced PtRu/Ti0.7Mo0.7O2 Catalysts for Direct Methanol Fuel Cells(Trường Đại học Nguyễn Tất Thành (Tạp chí Khoa học công nghệ NTT), 2018-01-02) Ho, Thi Van Thanh; Bach, Long Giang; Dai, VietInvestigating the novel Ti0.7Mo0.3O2 material can just as easily be used as a conductive support for PtRu for DMFCs to prevent not only the carbon corrosion but also improved activity of catalyst due to some functional advantages of novel Ti0.7Mo0.3O2 support. The Ti0.7Mo0.3O2 nanoparticle have good crystallinity with well-defined fringes corresponding to the 3.45 Å spacing value of the {101} plane of anatase TiO2, which were good according to the XRD pattern. The BET surface area measurements showed that the Ti0.7Mo0.3O2 possessed 125 m2 g-1 Fig. 3 shows the TEM measurement of Ti0.7Mo0.3O2 nanoparticle and Pt/Ti0.7Mo0.3O2, it can be observed that spherical PtRu alloy particles with an average particle size of 2-4 nm were uniformly anchored on the surface of Ti0.7Mo0.3O2 support. More importantly, we found that there has a strong metal support interaction (SMSI) between the PtRu noble metal and the Ti0.7Mo0.3O2 support material - resulting in facile electron donation from the Ti0.7Mo0.3O2 support to PtRu metal with an ultimate drastic decrease in the d-band vacancy of Pt.
- Tài liệuRemoval of Cu2+ from Aqueous Water by Adsorption onto the Efficient and Recyclable Durian Shell-Derived Activated Carbon(Trường Đại học Nguyễn Tất Thành, 2018-02-01) Bach, Long Giang; Dai Viet; Nguyen, Duy Trinh; Van, Thị Thanh Ho; Tran, Van ThuanVestigated the use of durian shell-derived activated carbon (DSAC) for the removal of Cu2+. To determine the optimal condition for Cu2+ removal, the response surface methodology (RSM) was used to establish a second-order polynomial model with variables such as Cu2+ concentration (Ci), adsorbent dosage (dDSAC) and pH. With R2 = 0.9847 and P-value < 0.0001, the model was proved to be statistically significant. The RSM based confirmation test revealed that the removal of Cu2+ was maximum (99.6%) at optimal conditions: Ci = 61.6 mg/L, dDSAC = 5.0 g/L and pH = 5.2. Based on calculated R2, data fitness for adsorption isotherms were positioned as follows: Langmuir > Tempkin > Freundlich. In other words, monolayer adsorption was the most favorable behavior with maximum capacity of 76.92 mg/g from Langmuir model. Interestingly, DSAC was reused at least five times without a considerable decrease of Cu2+ removal efficiency. Therefore, durian shell can be used as a highly effective, reusable and promising raw material to fabricate the activated carbon.
- Tài liệuSynthesis the New Nanostructure Ti0.7Ir0.3O2 via Low Temperature Hydrothermal Process(Trường Đại học Nguyễn Tất Thành, 2018-02-01) Huynh, Thien Tai; Nguyen, Van At; Pham, Quoc Hau; Bach, Long GiangIn this paper, the novel nanostructure Ti0.7Ir0.3O2 was prepared for the first time via low temperature hydrothermal process. The synthesis process for the new nanostructure Ti0.7Ir0.3O2 was studied in detail in this work. The impact of hydrothermal temperature as well as the reaction time on the dominant phase formation is extensively investigated in this work. We found that the Ti0.7Ir0.3O2 nanoparticles exist in both rutile and anatase phase. We found that the Ti0.7Ir0.3O2 nanoparticles with an irregular spherical shape with particle size of approximately 20-30nm with high crystallinity. In addition, we also found that the optimal condition to synthesize the Ti0.7Ir0.3O2 NPs is obtained at 210oC and 10 hours. The result not only introduces a promising catalyst support Ti0.7Ir0.3O2 for much needed fuel cells, but it also open a new material type of Ir doped TiO2.