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Al2O3-40 wt.% TiO2 coatings had the appearance of γ-Al2O3 and Al2TiO5 phases. In the plasma spray process, one part of α-Al2O3 phase changed to γ-Al2O3 phase. The α-Al2O3 phase interacted with rutile-TiO2 phase to form Al2TiO5 compound. The sealed coatings with aluminum phosphate also appeared aluminum phosphate compounds of AlPO4 and Al(PO3)3. ...
8 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 919 | Lượt tải: 0
A novel magnetic adsorbent derived from coffee husk was successfully synthesized by the HTC method in the presence of iron (III) salt and low temperature conditions (180 oC). The resulting MAM enhanced the adsorption capacity for different dyes, due to its porous structure, high surface area and large amounts of active adsorption sites resulting...
8 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 763 | Lượt tải: 0
Tỏi đen là một sản phẩm từ tỏi tươi, được sản xuất bằng cách ủ nhiệt trong môi trường có đủ độ ẩm trong thời gian dài. Tỏi đen có chứa các hợp chất phenolic, flavonoid và có hoạt tính kháng oxy hóa cao hơn nhiều so với tỏi tươi. Mục đích của nghiên cứu này là xác định ảnh hưởng của nhiệt độ ủ và thời gian ủ nhiệt đến sự chuyển hóa từ tỏi tươi th...
6 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 810 | Lượt tải: 0
Figure 5 shows that the absorption band with intensity at about 450 - 460 cm-1, corresponding to absorption band of the face-centered cubic structure of CeO2, and the broad absorption band with weak intensity at about 500 - 650 cm-1 assigned to the defects (or in the presence of oxygen vacancies) in the cubic structure of CeO2 [9, 10]. The chara...
7 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 768 | Lượt tải: 0
The recevied results show that the proposed method is more accurate than the classical fuzzy method. Moreover, the application of HA in control will be easier to understand and simpler than the use of fuzzy logic. It brings several benefits for controlling engineering systems. This paper used 5 linguistic values for the fuzzification of inputs a...
15 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 874 | Lượt tải: 0
Our chemical study of the acidic methanol extract of the D. metel whole plants led to the isolation and identification of five compounds, namely: kaempferol 3-O-β-D-glucosyl(1→2)-β- D-galactoside 7-O-β-D-glucoside (1), kaempferol 3-O-β-D-glucopyranosyl(1→2)-β-Dglucopyranoside-7-O-α-L-rhamnopyranoside (2), pinoresinol O-β-D-glucopyranoside (3), (...
8 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 760 | Lượt tải: 0
In the work, a PID design method with desired settling time is proposed for plants with transfer functions of the following types: first-order system, second-order system and integral first-order system. The method provides better performances than both the magnitude optimum method and the symmetric optimum method in the sense of overshoot and s...
11 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 830 | Lượt tải: 0
We reported on a symmetrically operated electrostatic actuator for improving the performance of scanning probe lithography. An analytical approach to evaluate the natural frequencies and capacitance of the probe was presented and verified by finite element method. The operation characteristics wee analyzed by using finite element method, which w...
10 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 768 | Lượt tải: 0
Compound 2 was also obtained as a white powder. The 13C-NMR and HSQC spectra confirmed 30 carbon signals including seven methyls, eight methylenes, eleven methines, and four quaternary carbons. The signals at δC 11.56 (C-18), 20.50 (C-19), 20.53 (C-21), 20.45 (C- 26), 21.60 (C-27), 14.31 (C-28), and 13.82 (C-29) indicated the presence of seven m...
5 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 710 | Lượt tải: 0
The result has identified optimal conditions for bioconversion of sugar cane bagasse into reducing sugars by mixed enzymes (Cell/Xyl, AltFAE, XpoAE ) at 400C, pH =5, 48 h incubation with the ratio of enzyme (Cell/Xyl, AltFAE, XpoAE) and substrate (sugar cane bagasse meal) are 3.1. The applying the experimental planning method led to find the mat...
10 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 895 | Lượt tải: 0