• Khảo sát thành phần hóa học của tinh dầu và gỗ Ngọc AmKhảo sát thành phần hóa học của tinh dầu và gỗ Ngọc Am

    (Bản scan) KẾT QUẢ VÀ THẢO LUẬN 1. Hàm lượng và các chỉ sô’ vật lý của tinh dầu Hàm lượng tinh dầu theo mẫu gỗ khô là 3,15 - 3,37%. Tinh dầu thu được có màu vàng nhạt, có mùi thơm. Tinh dầu tan tốt trong axeton, n-hexan, benzen, tan ít trong etanol. Các chỉ sô' vật lý (ở 25°C) như sau: Khối lượng riêng D = 0,973g/ml; Chiết xuất r| = 1,540; Góc...

    pdf4 trang | Chia sẻ: hachi492 | Ngày: 24/02/2022 | Lượt xem: 45 | Lượt tải: 0

  • Relations between drought-resistance and chlorophyll content of 25 local upland rice cultivals (oryza sativa L)Relations between drought-resistance and chlorophyll content of 25 local upland rice cultivals (oryza sativa L)

    Relationship between water retention capacity and chlorophyll content To study the relationship between water retention capacity and chlorophyll content of leaf tissues, we have tabulated the correlation between the average amount of water loss after one hour (%) and total chlorophyll content (chlorophyll a , chlorophyll b, chlorophyll (a+b)) a...

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  • The diversity of butterflies (lepidoptera, rhopalocera) in Phu Quoc national park, Kien Giang provinceThe diversity of butterflies (lepidoptera, rhopalocera) in Phu Quoc national park, Kien Giang province

    As with other Vietnamese natural forests or closed forests presents few butterflies but these butterflies do not fly in disturbed or non-forested areas such as Zeux-idia amethytus, Allotinus substrigosus, Discolanipa ethion and Syntarucus plinius. Regenerating forest presents the highest species number. This forest supports more microhabitat type...

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  • Biological properties and biomass culture of the microalgae chaetoceros muelleri from Giao Thuy mangrove for use in aquacultureBiological properties and biomass culture of the microalgae chaetoceros muelleri from Giao Thuy mangrove for use in aquaculture

    Fatty acid composition. Microalgae is a potential resource of fatty acids, particularly polyunsaturated fatty acids, PUFAs, which are of major importance determining the nutritional value of microalgae [5, 11, 13]. Fatty acid composition of C. muelleri was characterized and shown in Table 2. The distribution of fatty acids in C. muelleri is si...

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  • The nutritional value of diatoms from giao thuy mangrove water of the red river delta biosphere reserveThe nutritional value of diatoms from giao thuy mangrove water of the red river delta biosphere reserve

    The three diatom strains have a great variety of fatty acids ranging from saturated fatty acids (10:0 - 22:0) to polyunsaturated (18:2 - 22:6) fatty acids (Table 2). Among them, the saturated fatty acids palmitic (16:0) and the monounsaturated palmitoleic (16:1n-7) were dominant. They accounted for 60 - 80% of the total fatty acid. Myristic acid...

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  • Explant selection for spilanthes acmella (L) murr callus induction and optimization of the callus liquid cultureExplant selection for spilanthes acmella (L) murr callus induction and optimization of the callus liquid culture

    Optimization of Callus liquid culture Experimental results at each point based on the experimental design are shown in Table 2. Each data point shown in this Table is the average of 10 flasks. The Box-Wilson experimental design are a general series of experiments that have been developed to efficiently serve as a basis for deriving the mathemat...

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  • ECG dipole source localization in 3D human modelECG dipole source localization in 3D human model

    We used 50 dipoles with different orientations, magnitudes and positions as above. These dipoles are enough to estimate the effectiveness of our approach. The source localization was carried out three times to confirm the reliability of the obtained solution. The results in Table 3 show that the errors of dipole locations are acceptable. The av...

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  • Isolation and structural determination of some chemical constituents from hedyotis diffusa willd (rubiaceae) growing in Tuyen Quang provinceIsolation and structural determination of some chemical constituents from hedyotis diffusa willd (rubiaceae) growing in Tuyen Quang province

    Results and discussion ∗ Compound 1: The EI-MS data of (1) afforded m/z [M]+ 414, corresponding to molecular formula of C29H50O. The strong, wide IR absorption at 3450 cm−1 (assigned for O-H band absorption), at 1646 cm−1 (assigned for olefinic C=C band absorption) together with 1H-NMR signals at 3.49 ppm (1H, m, H-3), 5.35 ppm (1H, brd m, H-...

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  • Simulation study of tracer self - Diffusion mechanism in cobalt amorphous solidsSimulation study of tracer self - Diffusion mechanism in cobalt amorphous solids

    Conclusion The microstructure for the cobalt model containing 2 × 105 atoms is in good agreement with experimental data. The simulation result reveals that a large number of vacancy-simplexes which varies with relaxation degree in amorphous cobalt models. The relaxation has been accompanied with increased fraction of 4-simplex and decreased fra...

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  • Study of elastic moduli of Fe-C alloys pressure dependenceStudy of elastic moduli of Fe-C alloys pressure dependence

    Results and discussion The SMM caculations of the nearest neighbour distance and Young moduli of Fe-C interstitial alloys are shown in Figures 2 ÷ 7. The concentration dependence of the nearest neighbour distance r1(0, T) and Young moduli E of Fe-C interstitial alloys at zero pressure and temperature T is presented in Figures 2 and 3. As show ...

    pdf8 trang | Chia sẻ: hachi492 | Ngày: 24/02/2022 | Lượt xem: 63 | Lượt tải: 0