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  • A comparison of the cytotoxic activity of extracts from fruiting bodies and mycelial biomass of cordyceps neovolkiana (dl004) fungus - Nguyen Chi DungA comparison of the cytotoxic activity of extracts from fruiting bodies and mycelial biomass of cordyceps neovolkiana (dl004) fungus - Nguyen Chi Dung

    Our 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...

    pdf8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 859 | Lượt tải: 0

  • Effects of substituents on ch bond dissociation enthalpies of ent-Kaurane diterpenoids: a dft study - Ngo Dang Truong HaiEffects of substituents on ch bond dissociation enthalpies of ent-Kaurane diterpenoids: a dft study - Ngo Dang Truong Hai

    In 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...

    pdf7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 745 | 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 TrungMechanical properties and flame resistance of composite based on high density polyethylene/ethylene vinyl acetate blend and novel organically modified waste gypsum - Tran Huu Trung

    Gypsum 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 ...

    pdf9 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 841 | 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 NguyenSynthesis of solid acid-Base catalysts based on zn-sn and al-sn used for carbonylation of glycerol with urea into glycerol carbonate - Ba Khiem Nguyen

    All 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...

    pdf9 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 811 | Lượt tải: 0

  • Electrochemical behavior of mild steel in hcl 1m medium with the presence of rose myrtle leaves extraction -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...

    pdf8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 905 | Lượt tải: 0

  • Flavonoids from the leaves of aralia hiepiana - Nguyen Thi Dieu ThuanFlavonoids from the leaves of aralia hiepiana - Nguyen Thi Dieu Thuan

    Compound 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...

    pdf7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 781 | Lượt tải: 0

  • Insulin-Mimetic biflavones from a vietnamese medicinal plant selaginella tamariscina - Nguyen Dinh TuanInsulin-Mimetic biflavones from a vietnamese medicinal plant selaginella tamariscina - Nguyen Dinh Tuan

    Using 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...

    pdf8 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 865 | Lượt tải: 0

  • Extraction of polysaccharides from lingzhi by ultrasonic-Assisted enzymatic method - Tran Quoc HoaExtraction of polysaccharides from lingzhi by ultrasonic-Assisted enzymatic method - Tran Quoc Hoa

    In 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, ...

    pdf11 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 972 | Lượt tải: 0

  • Methoxyflavones from orthosiphon stamineus and their ptp1b inhibitory activities - Hoang Duc ThuanMethoxyflavones from orthosiphon stamineus and their ptp1b inhibitory activities - Hoang Duc Thuan

    Using combined chromatographic and spectroscopic methods, four flavones including 5- hydroxy-3,7,3',4'-tetramethoxyflavone (1), 3,5,7,3′,4′-pentamethoxyflavone (2), 3,5,3′- trihydroxy-7,4′-dimethoxyflavone (3), and 3,3′-dihydroxy-5,7,4′-trimethoxyflavone (4) were isolated and structurally identified from the methanol extract of the aerial parts ...

    pdf7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 707 | Lượt tải: 0

  • High protection performance of coating systems based on zinc rich primer and fluoropolymer coating - Vu Ke OanhHigh protection performance of coating systems based on zinc rich primer and fluoropolymer coating - Vu Ke Oanh

    Coatings systems with primer coatings based on inorganic zinc coatings and topcoat based on fluoropolymer, high-build fluoropolymer and polyurethane were tested by exposure at Ha Noi, Ha Long and Nha Trang stations. Gloss retention and electrochemical measurement were used for evaluating the protection performance of exposed coated steel panels....

    pdf7 trang | Chia sẻ: honghp95 | Ngày: 02/12/2020 | Lượt xem: 871 | Lượt tải: 0

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