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91.
云南干热河谷地区种子植物资源与开发利用初探 总被引:2,自引:0,他引:2
周元 《中国野生植物资源》2001,20(6):16-18
云南干热河谷植被均为耐旱的旱生植被,主要有以下三种类型:1)半稀树草原(Semi-savanna)型植被;2)肉质多刺灌丛;3)在金沙江上游滇西北的亚热带性的干热河谷地区分布着类似马基(Maquis-like)型的多刺小叶矮生灌丛。按其产物和用途可分为6类:药用植物、纤维植物、树脂和树胶植物、芳香油植物以及淀粉植物等。资源破坏性开发和环境的变化,使现存资源的保护和开发利用成为目前的主要问题。 相似文献
92.
Isolation of bacterial consortia for degradation of p-nitrophenol from agricultural soil 总被引:1,自引:0,他引:1
bacterial consortium has been isolated containing Pseudomonas spp. strains S1 and S2, which was able to degrade p‐nitrophenol (PNP). The strains were isolated from agricultural soil contaminated with organophosphorus pesticides. Pseudomonas spp. strain S2 could convert p‐nitrophenol to 4‐nitrocatechol (4NC) after pre‐exposure to phenol, when PNP was used as the only carbon source in the medium. Pseudomonas spp. strain S2, when mixed with strain S1 in the ratio 1:5 respectively, decolorised PNP completely. 相似文献
93.
Kim K.Y. Cho Y.S. Sohn B.K. Park R.D. Shim J.H. Jung S.J. Kim Y.W. Seong K.Y. 《Plant and Soil》2002,238(2):267-272
Growth response of hot pepper (Capsicum annuum L.) inoculated with the arbuscular mycorrhizal (AM) fungus, Glomus intraradices Schenck and Smith was evaluated in a greenhouse study. Three treatments in a soil-based medium amended with rock phosphate were: (1) control (CON), (2) inoculation of G. intraradices as a freshly prepared soil mixture of spores, hyphae and colonized roots of Sorghum vulgare (FM), and (3) inoculation of the fungus as cold-stored mixed inoculum (CM). Colonization at 14 weeks after inoculation with CM was 42.5%, but was significantly lower with FM (14.5%). Inoculation with G. intraradices as FM and CM increased growth of pepper, and total phosphorus and nitrogen uptake in shoots and roots compared with the CON treatment. Inoculation with CM resulted in significant increases in plant dry weight and chlorophyll concentration compared to the FM and CON treatments. Acid phosphatase activity in the rhizosphere was generally increased by AM fungal treatments. Highest acid phosphatase activity occurred at 14 weeks after inoculation with CM. Alkaline phosphatase activity in the CM treatment was significantly higher compared to that in CON and FM treatments throughout the growth period. Thus, cold storage of mixed inoculum enhanced colonization and growth-promoting activity of G. intraradices compared to freshly prepared inoculum. 相似文献
94.
Abdelghani El Asli Eckhard Boles Cornelis P. Hollenberg Mohamed Errami 《Biotechnology letters》2002,24(13):1101-1105
A xylose-fermenting bacterium of the family Enterobacteriaceae was isolated from olive mill wastewater. It converted xylose to ethanol with a yield of 0.19 g ethanol g–1 xylose. Although phenolic compounds normally inhibit pentose-utilizing microorganisms, this isolate was tolerant to phenol. Both the yield and the productivity of xylose fermentation decreased by 30% when phenol was added at a final concentration of 0.8 g phenol l–1. Xylose (23 g l–1) was totally fermented to ethanol (4.3 g l–1) within 48 h in the absence of phenol; however, in the presence of 0.8 g phenol l–1, only 3.3 g ethanol l–1 was obtained from the same starting concentration of xylose after 70 h. 相似文献
95.
Seungdo Kim Taeyeon Hwang Michael Overcash 《The International Journal of Life Cycle Assessment》2001,6(1):35-43
The environmental performance of a color computer monitor is investigated by implementing a Life Cycle Assessment. The goal
of this study is to collect LCI data of foreground systems, to identify hot spots, and to introduce life cycle thinking at
the product design stage. Secondary data are used in the background system, and site-specific data are collected in the foreground
system.
Results show that the use phase is the most contributing phase. The operating mode and the energy saving mode during the overall
use phase contribute to the total by 59% and by 9.9%, respectively. In the production phase, the cathode ray tube assembly
process and the printed circuit board assembly process are the most contributing processes. The sensitivity analysis on the
use pattern scenario shows that the contribution ratio of the use phase ranges from 32% to 84%. Even in the home use case,
which is the best case scenario, the use phase is one of the most contributing processes to the environmental performance
of the color computer monitor. There is no significant difference in the choice of the impact assessment methodologies for
identifying the improvement opportunities.
For the external use of Life Cycle Assessment in a short-run product for the market, it is recommended that Life Cycle Assessment
should be carried out in parallel with the product design stage. It is also necessary to have a pre-existing, in-house database
for a product group in order to accelerate life cycle procedures. 相似文献
96.
When tobacco leaf extracts are treated with phenol, ca 20% of the ribonuclease (RNase) activity survives and can be measured when the phenol is removed. After purification, the resistant RNase is inactivated by phenol; this suggests that tobacco leaves contain material that protects the RNase. Phenol-resistant RNase may be one of the TMV-RNA inactivating systems present in phenol extracts of tobacco leaves. 相似文献
97.
Beverly K. Pierson 《Photosynthesis research》1994,41(1):7-15
A personal historic account is presented of the discovery of the anoxygenic filamentous bacteria of hot springs:Heliothrix oregonensis andChloroflexus aurantiacus. The later discoveries of marine and hypersaline forms are also described. 相似文献
98.
《Free radical research》2013,47(1):102-111
AbstractAstaxanthin when esterified with ferulic acid is better singlet oxygen quencher with k2 = (1.58 ± 0.1) 1010 L mol? 1s? 1 in ethanol at 25°C compared with astaxanthin with k2 = (1.12 ± 0.01) 109 L mol? 1s? 1. The ferulate moiety in the astaxanthin diester is a better radical scavenger than free ferulic acid as seen from the rate constant of scavenging of 1-hydroxyethyl radicals in ethanol at 25°C with a second-order rate constant of (1.68 ± 0.1) 108 L mol? 1s? 1 compared with (1.60 ± 0.03) 107 L mol? 1s? 1 for the astaxanthin:ferulic acid mixture, 1:2 equivalents. The mutual enhancement of antioxidant activity for the newly synthetized astaxanthin diferulate becoming a bifunctional antioxidant is rationalized according to a two-dimensional classification plot for electron donation and electron acceptance capability. 相似文献
99.
H E Knoell 《Biochemical and biophysical research communications》1979,91(3):919-925
A soluble enzyme complex (~ 2×106 daltons) was isolated from the cytoplasmic membrane of . It contains a high amount of 2-octaprenyl phenol, whereas ubiquinone-8, phospholipids and typical enzymes of the cytoplasmic membrane are largely excluded. Upon addition of a cytoplasmic enzyme and substrates, the pool of 2-octaprenyl phenol was quantitatively processed to ubiquinone-8. It is assumed that this complex represents the ubiquinone-8 synthesis apparatus supplied with the substrate 2-octaprenyl phenol. 相似文献
100.
Jan A. Gossen Wiljo J. F. de Leeuw Aart Verwest Paul H. M. Lohman Jan Vijg 《Mutation research》1991,250(1-2):423-429
To study spontaneous and induced mutagenesis in vivo we recently constructed a series of transgenic mice harboring different numbers of bacteriophage lambda shuttle vectors, provided with a LacZ mutational target gene, integrated in their genome. The transgenic mice enabled analysis of spontaneous and induced mutation frequencies in postmitotic tissues like liver and brain. The obtained data indicated spontaneous mutation frequencies in the order of −5 - 10−6. Here we report a 25–100 times higher spontaneous mutation frequency in liver and brain DNA of mice from strain 35.5, with the lambda-gt10LacZ concatemer integrated on the X-chromosome. These results indicate the presence of a mutational ‘hot spot’ in the mammalian somatic genome in vivo. 相似文献