Tổng hợp tài liệu, ebook Khoa Học Tự Nhiên tham khảo.
Sự có mặt của Huperzine A có trong lá cây Thạch tùng răng cưa ở Đà Lạt đã được định tính sơ bộ bằng phương pháp sắc kí lớp mỏng (TLC) với hệ dung môi phù hợp là chloroform- isopropanol- ethyl acetate- ammonia (4- 1,5- 4- 0,1). Đã thiết lập được điều kiện sắc ký lỏng hiệu năng cao HPLC phân tích định tính và định lượng Huperzine A ở bước sóng ...
6 trang | Chia sẻ: yendt2356 | Ngày: 30/11/2020 | Lượt xem: 557 | Lượt tải: 0
SUMMARY Study area consists of 2 protected areas in Ha Giang Province with poor surveys on biodiversity values: Du Gia Nature Reserve (11,795 ha) with domination of lowland, montane tropical evergreen forest and small area of limestone evergreen forest. Khau Ca species habitat Tonkin snub-nosed monkey conservation area (2,024 ha) is predominated...
10 trang | Chia sẻ: thucuc2301 | Ngày: 30/11/2020 | Lượt xem: 542 | Lượt tải: 0
Nano Silver has been proven to be effectively applied in the field of biotechnology. In the area of plant biotechnology, nanoparticles have positive and negative effect on the growth of plants. The impact of nanoparticles on plant depends on the composition, content, size, chemical and physical propreties of nanoparticles as well as the plant sp...
11 trang | Chia sẻ: yendt2356 | Ngày: 30/11/2020 | Lượt xem: 510 | Lượt tải: 0
SUMMARY A study of Lepidopteran diversity was carried out from 5 to 25 September 2012, at 6 transects of different habitats at Krong Trai Nature Reserve, Son Hoa District of Phu Yen Province. The transects that are representative for almost all habitats of the Reserve: secondary forest near the natural forest, poor evergreen secondary forest, se...
9 trang | Chia sẻ: thucuc2301 | Ngày: 30/11/2020 | Lượt xem: 635 | Lượt tải: 0
SUMMARY Based on 924 collected fish specimens of ten field surveys from 9 locations in the Red River valley within the territory of the Thai Binh and Nam Dinh provinces during December 2010 to August 2012, the total of 193 species of fish species belonging to 131 genera, 53 families and 13 orders have been recorded. There are 130 species, 61 gen...
19 trang | Chia sẻ: thucuc2301 | Ngày: 30/11/2020 | Lượt xem: 560 | Lượt tải: 0
SUMMARY Among total 22 specimens of spiny lobster collected from two fieldtrips in the Cu Lao Cham marine protected area (MPA), Quang Nam province on May and November 2012, we have identified six species belong to genus Panulirus: Panulirus longipes, P. stimpsoni, P. versicolor, P. ornatus, P. penicillatus and P. homarus. At present, the speci...
7 trang | Chia sẻ: thucuc2301 | Ngày: 30/11/2020 | Lượt xem: 715 | Lượt tải: 0
Paphiopedilum villosum var. annamense Rolfe. is the attractive pot plant characterize by its larger and beautiful flower. Wild population of that orchid are now considered to be rare in nature as a result of habitat destruction and commercial preference. Thus, it is very important that actions should be taken to conserve this orchid before it be...
9 trang | Chia sẻ: yendt2356 | Ngày: 30/11/2020 | Lượt xem: 503 | Lượt tải: 0
SUMMARY The rat lungworm, Angiostrongylus cantonensis, is a nematode that parasites the lungs of rats - the natural definitive hosts of the nematodes. This nematode can cause Angiostrongyliasis for human when people eat uncooked/undercooked snails infected with infective larvae (L3). In Vietnam, although some suspected Angiostrongyliasis cases h...
7 trang | Chia sẻ: thucuc2301 | Ngày: 30/11/2020 | Lượt xem: 555 | Lượt tải: 0
Chitosan with initial molecular weight (Mw) about 193 kDa and the deacetylation degree of about 80% was irradiated by gamma rays from a Co-60 source in powder state for degradation. The results on Mw estimation by gel permeation chromatography method indicated that oligochitosan products with Mw from 3.7 to 28.9 kDa were successfully prepared by...
6 trang | Chia sẻ: yendt2356 | Ngày: 30/11/2020 | Lượt xem: 534 | Lượt tải: 0
SUMMARY In this paper, the construction method outlined criteria identify key sensitive areas (hot spots) of interest of marine ecosystems in the planning of Biodiversity Conservation in Vietnam. Set up criteria for determining the influence of the nature and impact of humans on the ecosystem of the national park of marine ecosystems was studied...
14 trang | Chia sẻ: thucuc2301 | Ngày: 30/11/2020 | Lượt xem: 523 | Lượt tải: 0