Anthraquinones from hedyotis pinifolia - Le Hoang DuyThe ethyl acetate extract was subjected to a series of chromatographic procedures, leading to the isolation of 12 mg of fine orange needles. Initial inspection of the 1H and 13C-NMR spectra of this product indicated the doubling signals for most protons and carbons. These facts suggested that perhaps the product was a dimeric anthraquinone o...
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Fabrication of silver-Nanoparticles-embedded polymer masterbatchs with excellent antibacterial performanceThe silver-nanoparticles-embedded PEbased polymer masterbatchs with excellent antibacterial performance were successfully synthesized. A fine dispersion of silver nanoparticles in PE polymer matrix was obtained with use of appropriate dispersion supporting reagents of Disperplast 1010 (BYK), Chimassorb 81 (Ciba), Irganox 1010 (Ciba). At a si...
8 trang | Chia sẻ: honghp95 | Ngày: 01/12/2020 | Lượt xem: 711 | Lượt tải: 0
Heck reactions of aryl halides with styrene using 1-Butyl-3-methylimidazolium bromide ionic liquid as a green solvent under microwave irradiationIn summary, three ionic liquids including 1- butyl-3-methylimidazolium bromide, 1-hexyl-3- methylimidazolium bromide, and 1-octyl-3- methylimidazolium bromide, respectively, were synthesized under microwave irradiation condition, and characterized by 1H and 13C NMR, and MS. The three ionic liquids were used as green solvents the Heck cross-c...
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Norisoprenoid, phenolic and steroidal constituents from mallotus luchenensis - Nguyen Huu Toan PhanThe 1H-NMR spectrum of 3 showed two singlet signals at δH 6.68 and 6.70 which were assigned to two aromatic protons. A broad singlet at δH 7.07 was assigned to a proton of a gallyol residue. The presence of an anomeric proton signal was upfield shifted to δH 6.38 (d, J = 2.0 Hz). The 13C-NMR and DEPT spectra of 3 showed the signals of three ...
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Characteristics and reducibility of nanosized La1-XCexCoO3 perovskites synthesized by reactive grinding - Nguyen Tien ThaoTwo ground La1-xCexCoO3 perovskites have been successfully synthesized and characterized. The solid solutions have rather high surface area and consist of elementary nanometric particles. The existence of small spaces between nanoparticles of perovskite makes these ground materials more porous. Under hydrogen atmosphere, the reduction of cob...
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Prediction of vapor-Liquid equilibria of binary mixtures using quantum calculations and activity coefficient modelsThe VLE data P-x-y of two binary systems methanol(1) - benzene(2) and toluene(1) - chlorobenzene(2) at T = 333.15 K and T = 343.15 K obtained over the pressure ranges from 0.4 to 0.7 bar and from 0.1 to 0.3 bar, respectively. For the three binary systems in this work the VLE data resulting from COSMO-SAC calculation were compared with exper...
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The blue shifts of the c-H and n-h bonds in the complexes of chx3 (x = f, cl, br) and hno: a theoretical study - Nguyễn Tiến TrungEach complex pairing HNO and CHX3 (X: F, Cl, Br) contains five separate minima on the potential energy surface. The binding energies obtained at the MP2/6-311++G(d,p) level are from 7 to 11 kJ.mol-1 with the BSSE correction and from 4 to 8 kJ.mol-1 with both the ZPE and BSSE corrections. The most stable are the complexes pairing CHBr3 with H...
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Monte carlo simulation of vapor - Liquid equilibria of hydrogen using ab initio intermolecular potentialsThe vapour-liquid phase equilibria and thermodynamic properties of the pure fluid hydrogen were calculated successfully with our developed computer simulation programs GEMC-NVT and GEMC-NPT using ab initio intermolecular pair potentials. The simulation results turn out to be in very good agreement with experimental data and with those from ...
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Synthesis of acyclovir as an antiherpes-Virus drug - Trần Quang HưngThis report describes a one-pot process for the preparation of acyclovir from guanine. Reacting N2,N9-diprotected guanine with 1- acetyl-2-acetylmethoxy-ethyleneglycol in present of phosphoric acid as catalyst provide ACV with high yield and good regioselectivity. Therefore, the purification was simple, inexpensive and conforming to pilot sc...
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Microwave-Assisted direct synthesis of some 5-alkyl- 2-amino-1,3,4-thiadiazoles - Nguyễn Đình ThanhThe separation of products out of the reaction mixture depended on carbon chain of aliphatic acid: in case of acetic acid and propionic acid, the reaction mixture was poured into ice-water and the obtained solution was neutralized by ammonia solution to pH 8; in remained cases, firsts, the reaction mixture was distilled by steam to remove u...
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