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Acute toxicity of the ethanol extract and ethyl acetate fraction of eupatorium fortunei to daphnia magna - Pham Thanh NgaThe present work indicated that the ethanol extract and its ethyl acetate fraction of Eupatorium fortunei Turcz had the different acute toxicity to D. magna after 24 and 48 hours of exposure. The ethanol extract was less toxic to D. magna with LC50-24h and LC50-48h of 247 and 183 mg.L-1, respectively. In terms of ethyl acetate fraction, the valu...
7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 805 | Lượt tải: 0
Energy consumption and air emission inventory for transportation sectors of Viet Nam - Pham Thi HueAs calculated in Vietnam 2016, total energy consumption and CO2 emission of N3, N27÷N35, N36 are 15.90 Mtoe and 44.20 Mt, respectively. The results show the biggest contribution of transport activities in term of energy consumption and air emissions of Vietnamese economy. The study also evidences that among transportation service sectors, the r...
6 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 828 | Lượt tải: 0
A comparison of the cytotoxic activity of extracts from fruiting bodies and mycelial biomass of cordyceps neovolkiana (dl004) fungus - Nguyen Chi DungOur research showed that the mycelial biomass extracts of Cordyceps neovolkiana fungus have tronger cytotoxic activity against MCF-7 and Jurkat T cells than the fruit bodies in three extracts: EtOH, PE and EA. This result was helpful and useful to the development of C.neovolkiana cultivation process for efficient production of functional foods o...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 895 | Lượt tải: 0
Effects of substituents on ch bond dissociation enthalpies of ent-Kaurane diterpenoids: a dft study - Ngo Dang Truong HaiIn this study, the BDE thermochemical parameter characterizing for HAT antioxidant mechanism of seven ent-kaurane diterpenoids extracted from Croton tonkinensis Gagnep. has been calculated using density functional theory (DFT) method. The obtained results reveal that BDEs calculated at M05-2X/6-31+G(d) vary from 83.8 to 90.9 kcal/mol. These stud...
7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 802 | Lượt tải: 0
Mechanical properties and flame resistance of composite based on high density polyethylene/ethylene vinyl acetate blend and novel organically modified waste gypsum - Tran Huu TrungGypsum filler was successfully modified by EBS using melt-mixing method at 155 oC for 30 minutes. Stretching vibration of H-O-H shifted from 1,623 cm-1 to 1,629 cm-1 could be assigned to the hydrogen bonds between –OH groups of gypsum and amide groups of EBS. By adding 5 wt.% APP and 3 wt% ZB into HDPE/EVA/Gyp composite, the material reached V2 ...
9 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 894 | Lượt tải: 0
Synthesis of solid acid-Base catalysts based on zn-sn and al-sn used for carbonylation of glycerol with urea into glycerol carbonate - Ba Khiem NguyenAll in all, the solid acid-base catalysts for carbonylation reaction from glycerol to glycerol carbonate was employed in this study. The structure of the products was studied using XRD, SEM. The products of glycerol conversion product was also tested by gas chromatography. As the results, the Zn-Sn catalyst for conversion, selectivity and effici...
9 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 864 | Lượt tải: 0
Electrochemical behavior of mild steel in hcl 1m medium with the presence of rose myrtle leaves extraction -The main findings of this research were: The natural compounds in R. tomentosa (Rose myrtle) extract acts as a capable inhibitor for preventing corrosion on steel substrate in HCl 1M solution with the optimal inhibition efficiency reaches 85.6 % at 0.9 g/L from potentiodynamic polarization result. Followed the obtained results on LPR and EIS me...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 943 | Lượt tải: 0
Flavonoids from the leaves of aralia hiepiana - Nguyen Thi Dieu ThuanCompound 5 was isolated as a yellow amorphous powder. The 1H NMR spectra displayed pattern of flavone glycoside, with characteristic signals of two doublet signals in ring A at δH 6.45 (1H, d, J = 2.0 Hz, H-6) and 6.84 (1H, d, J = 2.0 Hz, H-8), signals of 1,4-disubstituted ring B of a flavonoid at δH 7.96 (2H, d, J = 8.5 Hz, H-2', H-6'), 6.96 (2...
7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 821 | Lượt tải: 0
Insulin-Mimetic biflavones from a vietnamese medicinal plant selaginella tamariscina - Nguyen Dinh TuanUsing combined chromatographic and spectroscopic methods, four biflavones including amentoflavone (1), robustaflavone (2), cupressuflavone (3), and 3,8′′-biapogenin (4) were isolated and structurally identified from the methanol extract of Selaginella tamariscina. All of the isolates (1‒4) were investigated for their stimulatory effects on 2-NBD...
8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 910 | Lượt tải: 0
Extraction of polysaccharides from lingzhi by ultrasonic-Assisted enzymatic method - Tran Quoc HoaIn this study, all the statistical indicators supported that response surface model was a successful tool to describe the ultrasonic process in extracting polysaccharides from Lingzhi. The optimal parameters of the polysaccharide extraction by ultrasonic-assisted enzymatic method were: extraction time of 144min, extraction temperature of 55 °C, ...
11 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 1033 | Lượt tải: 0
