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Application of passive remote sensing to investigate transmissivities of trees canopies using ground-Based upward-looking microwave radiometersBased on the field measurement campaign in 2015 and 2016, performed by using groundbased upward-looking microwave radiometers in L band and X band microwave transmissivities of khaya senegalensis canopies the brightness temperatures and the transmissivity of the canopy have been calculated and discussed. These results provide empirical evidence ...
13 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 879 | Lượt tải: 0
Uptake capacity of metals (Al, Cu, Pb, Sn, Zn) by Vetiveria zizanioides in contaminated water from Dong Xam metal production trade village, Thai Binh, VietnamThe present study showed that vetiver could highly accumulate metals Al, Cu, Pb, Sn and Zn in the upper part of the shoot. Thus, the vetiver may serve as an important means for waste water treatment. The roots and upper parts of shoots accumulated Al concentration from 17-30 times and 1.2 times higher than “reference plant”, respectively. T...
11 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 974 | Lượt tải: 0
Synthesis of (5r*,6r*)-6-(3-(tertbutyldimethylsilyloxy)prop-1-ynyl)-5- hydroxypiperidin-2-one - Dau Xuan DucWe have examined two pathways to synthesize a cis disubstituted piperidinone. The first one was not efficient due to the failure in conversion of 3 to 14. Following the second route we have synthesized the racemic (5R*,6R*)-6-(3-(tert-Butyldimethylsilyloxy)prop-1-ynyl)-5- hydroxypiperidin-2-one in 10.3 % overall yield over 7 steps.
7 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 866 | Lượt tải: 0
Ammonium transport experiments in soil columns: estimating transport parameters - Nguyễn Thị Minh TrangBased on the conservative tracer experiments (Cl-), the longitudinal dispersivity λ and the hydrodynamic dispersion coefficient D of Con Son soil were estimated to 0.2 cm and 8.40 cm2 h- 1, respectively. The small values found, indicates that the used soil is a relatively homogeneous porous media. The ammonium BTCs for six aqueous concentrations...
12 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 959 | Lượt tải: 0
Different fructose feeding strategies for poly(3-Hydroxybutyrate) production byyangia sp. nd199The study showed that the strain Yangia sp. ND199 belongs to second PHA producer group that canaccumulate PHB together with cell growth. CDW of 7.8 g/l and PHB content of 49 wt% were achieved in batch fermentation. High CDW of 78.5 g/l and PHB content of 67.5 wt% were obtained by using two-stage fed-batch fermentation in which the first stage wa...
7 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 901 | Lượt tải: 0
Development of spectrophotometric method for determination of ceftazidime with the bratton– marshall reagent in pharmaceutical preparationThe proposed method was applied successfully for determination of the studied drugs in their pharmaceutical dosage forms (injections). The relative standard deviation values are below 2 % indicating the precision of the method. The validations of the proposed methods were further confirmed by recovery studies. The % recovery vary from 98.95 ± 0....
9 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 863 | Lượt tải: 0
Secondary metabolites from micromonospora sp. (g044) - Cao Duc TuanCompound 5 was obtained as a white solid. The ESI mass spectrum of 5 showed a base peak at m/z 245.1 [M+H]+. In the 1H-NMR, compound 5 displayed signals of two olefin protons at δH 5.72 (1H, d, J= 8.0 Hz, H-5), 8.02 (1H, d, J= 8.0 Hz, H-6) and a set of the protons of arabionoside sugar moiety at δH 3.75 (1H, dd, J=3.0, 12.5 Hz, Ha-5), 3.86 (1H,...
7 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 847 | Lượt tải: 0
Effect of modified atmosphere packaging (map) and postharvest treatments on quality of litchi fruits during storageThe results showed that treatment of litchi by hot water at 47 oC for 7 min., then dipped in a oxalic acid solution (pH = 3 for 6 min.), finally packed in MAP bags with the thickness of 30 µm (incorporated 3-5 % silica additives) and stored at 4 ± 1oC, 90 % humidity can extend the storage time to 35 days (5 weeks) at the decay incidence < 10 %, ...
8 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 829 | Lượt tải: 0
High order sliding mode control with anti-Sway based compensation on artificial neural network by pso algorithm for overhead craneFrom Figure 4, Figure 5, Figure 6 and Figure 7, it can be seen that ability of resisting disturbance of high order sliding mode controller is very good. But, the quality of swing angle is not good . Although the trolley reaches desired position, but the oscillation of the load is still large. To fix this problem, RBFNs is used for generating op...
10 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 761 | Lượt tải: 0
An initial study on chemical constituents of bischofia javanica - Nguyen Thi MaiCompounds 3, 4, and 5 were identified as hexyl-O-β-D-glucopyranoside [16], friedelan-3- one [17], and gallic acid [18] based on their spectral evidence, which were in agreement with those of the reported data in the literature, respectively. Among isolated compounds, the compounds 1, 2 and 3 were firstly isolated from B. javanica leaves. Meanwhi...
7 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 841 | Lượt tải: 0
