17 research outputs found
Environmental flow requirements for integrated water resources allocation in the Yellow River Basin, China
The China forest products trade: overview of Asia-Pacific supplying countries, impacts and implications
Over 70 % of China's timber product imports are supplied by countries in the Asia Pacific region, and China is the dominant forest product market for many of these countries. Unsustainable harvesting practices, illegal logging, and negative impacts on community livelihoods plague many of these supplying countries. The countries may be divided into those still harvesting and exporting timber from natural forests on a large scale and those which have gone past their highest levels of natural forest timber harvesting and are now more aggressively pursuing plantation development and processing. Apart from Russia, China's top Asia Pacific timber suppliers could at best maintain current supply, with natural forest resources being depleted in less than 20 years. Resource limits also constrain expansion and/or long-term continuation of processed product export to China. Greater attention and action on the part of governments, market leaders, and international organizations is needed to address negative impacts, shifting supply to a sustainable, legal, and equitable basis and to determine from where China's long-term supply will come
Fluorescence and FTIR study of the pressure-induced denaturation of bovine pancreas trypsin
pH and salt effects on the aggregation behaviour of star polymer with G1 polyamidoamine core and terminal amphiphilic blocks
Historical biogeography of Eusattus muricatus (Coleoptera: Tenebrionidae) within the Great Basin, western North America
Enhanced production of elastase by Bacillus licheniformis ZJUEL31410: optimization of cultivation conditions using response surface methodology
Sequential methodology based on the application of three types of experimental designs was used to optimize the fermentation conditions for elastase production from mutant strain ZJUEL31410 of Bacillus licheniformis in shaking flask cultures. The optimal cultivation conditions stimulating the maximal elastase production consist of 220 r/min shaking speed, 25 h fermentation time, 5% (v/v) inoculums volume, 25 ml medium volume in 250 ml Erlenmeyer flask and 18 h seed age. Under the optimized conditions, the predicted maximal elastase activity was 495 U/ml. The application of response surface methodology resulted in a significant enhancement in elastase production. The effects of other factors such as elastin and the growth factor (corn steep flour) on elastase production and cell growth were also investigated in the current study. The elastin had no significant effect on enzyme-improved production. It is still not clear whether the elastin plays a role as a nitrogen source or not. Corn steep flour was verified to be the best and required factor for elastase production and cell growth by Bacillus licheniformis ZJUEL31410