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Đang hiển thị 1 - 5 trong tổng số 33
- Tài liệuThe Relationship between Macroeconomic Factors and the Level of Non-Performing Loans (NPLs) of Commercial Banks in Vietnam(International Journal of Scientific & Engineering Research, 2017-03) Nguyen, Huu Quang; Nguyen, Xuan NhiThis article is to estimate the effects of macroeconomic factors on the the level of non-performing loans (NPLs) of Commercial Banks in Vietnam by using econometric model on the commercial banks for the 2004-2015 periods. It is obvious that banks have to take risk all the time and there are three major risks, including credit risk, market risk and operational risk (Perez, 2014). Credit risk is one of the most important kinds of risk in commercial banking sector. The Basel Committee on Banking Supervision defines credit risk as the potential that a commercial bank borrower, or counter party, will fail to meet its payment obligations regarding the terms agreed with the commercial bank (Perez, 2014). This study also finds that NPLs are not the problem of the commercial bank but the government must consider it carefully. It is clear that commercial banks must have a right thought about NPLs as well as analyze the reasons to give the reasonable solutions to solve the issue. In addition, this study also points out that if the commercial banks in Vietnam try to hide the bad debt, the real status of the commercial bank will be reflected unexpectedly, leading to the results will affect to the capital supply of national economics
- Tài liệuThe Comparison of Surface Modification Methods of the Heavy Metals Adsorption of Activated Carbon from Rice Husk(Trường Đại học Nguyễn Tất Thành, 2018-02-01) Thai, Hoa Mai; Van, Thi Thanh Ho; Nguyen, Bao PhamPresent Surface modification of activated carbon (AC) could be done through different methods in order to modify their specific physical and chemical properties to facilitate metals removal from wastewater. Three methods were used to modify the rice husk AC (RHAC) including the use of (1) HNO3, (2) dithizone and (3) the combination of HNO3 with dithizone. These modification agents were increased its affinity towards the desired pollutant. The modification methods demonstrated the effective process for the metal ions adsorption capability and the removal of them from water. For Ni2+ and Cd2+ adsorption, RHAC was modified by HNO3 giving the best adsorption capacity in comparison with using dithizone or the combination of HNO3 with dithizone. That adsorption was reached 17.23 mg/g for Ni2+ and 29.61 mg/g for Cd2+. Additionally, the surface area, which was characterized by BET (Brunauer–Emmett–Teller) of RHAC, was 710.8 m2/g and DA micropore volume was 0.447 (cm3/g). Especially, the only modified RHACs had the peak of N-H functional group by using Fourier transform infrared spectrum (FTIR). Besides, the only RHAC modification by HNO3 had peak of C=O. That significantly contributed to increase the metal ions adsorption capacity of rhac
- 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.
- 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 liệuHigh Photocatalytic Activity of Oliver-Like BiVO4 for Rhodamine B Degradation under Visible Light Irradiation(Trường Đại học Nguyễn Tất Thành, 2018-02-01) Nguyen, Huu Vinh; Tran, Van Thuan; Do, Sy Trung; Nguyen, Duy TrinhReport the facial synthesis of BiVO4 crystals with different morphologies by the solvothermal and hydrothermal process. The phase structure and morphology as-synthesized samples were characterized by XRD, FE-SEM, and UV-vis DRS spectroscopy. We also investigated the photocatalytic activity of BiVO4 for the decomposition of rhodamine B (RhB) under visible light irradiation. The results showed that oliver-like BiVO4 was obtained when using the mixed solvent of ethylene glycol and water while starflower-like BiVO4 was obtained using the mixed solvent of ethylene glycol monomethyl ether and water. The hydrothermal evolution process the BiVO4 product with a rod-like morphology. Oliver-like BiVO4 with pure monoclinic scheelite phase and high specific surface area exhibits efficient photodegradation of RhB (k = 7.82x10-3 min-1).