石油、天然气资源的生物技术利用

本文重点论述了现代生物技术应用于石油化工领域的发展现状及发展趋势,指出利用生物技术深度开发石油、天然气资源将极大地推动石油化工工业的发展,石油、天然气资源的生物技术利用是新世纪生物技术重点开发方向。

Physico-chemical characterization of a farmland affected by wastewater in relation to heavy metals

This study investigated selected properties of soils affected by wastewater and its relationship with some heavy metals. A free survey technique involving target sampling was used in siting soil profile pits. Soil samples were collected based on horizon differentiation and analyzed using routine and special analytical techniques. Soil data were subjected to correlation analysis using SAS program. Results show that all heavy metals studied had values above critical limits in the polluted soils using known standards and that these biotoxic metals decreased with soil depths. Highly significant (P=0.01 and 0.05) relationships were established between investigated heavy metals and some soil properties, especially soil pH and organic matter. Further studies involving more edaphic properties, biotoxic metals and their bioaccessibility in crops growing on wastewater soils will surely enhance knowledge and management of these highly anthropogenically influenced soils of the study site.

Energy and Water Optimization in Biofuel Plants

In this paper we address the topic of energy and water optimization in the production of bioethanol from corn and switchgrass. We show that in order for these manufacturing processes to be attractive,there is a need to go beyond traditional heat integration and water recycling techniques. Thus,we propose a strategy based on mathe-matical programming techniques to model and optimize the structure of the processes,and perform heat integration including the use of multi-effect distillation columns and integrated water networks to show that the energy effi-ciency and water consumption in bioethanol plants can be significantly improved. Specifically,under some circum-stances energy can even be produced and the water consumption can be reduced below the values required for the production of gasoline.

Whole process reclamation and utilization of wastes produced in the biological fermentation industry

Wastes yielded in the vintage process and the biological fermentation of itaconic acid and sodium gluconate of a winery in Shandong, such as grain stillage, melon lees, cornstarch protein residues, itacanic acid mother liquid, itaconic acid mycelium and sodium gluconate mycelium, were studied. High-activity biological protein feed, foliar fertilizer and irrigation fertilizer were generated from these wastes by applying biological/microbial technologies. Meanwhile, a whole set of technological pathways was put forward. As a result, the optimal economical and social benefits can be obtained with low natural resource consumption and environmental costs by converting wastes into useful matters. In conclusion, through the utilization of limited resources in the whole process of reclamation and utilization of wastes, the harmony promotion can be achieved between the economic system and the natural ecosystem.

Exploring Sustainable Development in Kibera： A Case Study

Kibera is the largest urban slum in Nairobi with over 900,000 inhabitants. This urban slum is plagued by unsanitary conditions, such as high density, dust, mud, squalor, hazards, litter, and smell. As a result of these deplorable conditions, Umande Trust, a local non-governmental organization （NGO）, has developed a new educational initiative using biotechnology to turn human waste into gas for cooking. This initiative supports Freire＇s （2000） theory pedagogy of the oppressed, which will serve as the theoretical framework, in which the people who have been oppressed and/or have had to endure the horrible conditions in which they live play an active role in their development to regain their humanity. Jacobson （2004） raised a critical question that will be the focal point of this study regarding development： ＂Who is better suited to help Africa determine her future＂ （p. 75）. Using a qualitative case study design, the answer to this question will be answered in terms of Kibera specifically and its use of bio-technology as a sustainable development initiative. This study will also assess the use of communication in this approach.

Soil phosphorus bioavailability assessed by XANES and Hedley sequential fractionation technique in a glacier foreland chronosequence in Gongga Mountain, Southwestern China

The primary productivity of terrestrial ecosystems is influenced by soil phosphorus bioavailability, which depends largely on chemical fractions of phosphorus. The sequential fractionation technique developed by Hedley et al. or its subsequent modification is a well-known method to determine soil phosphorus forms. Hedley sequential fractionation technique separates the phosphorus into fractions based on their different chemical solubilities in extractants with certain chemical properties. Recently, synchrotron-based X-ray absorption near edge structure(XANES) spectroscopy has been employed to measure soil phosphorus species directly and non-invasively. The XANES method provides information concerning local structure and chemical information of target elements at a molecular level. Thus, it can distinguish phosphorus fractions bound by metal oxides or hydroxides(such as Fe, Al, and Ca). In this present work, the phosphorus speciation of topsoil along a glacial foreland chronosequence in Gongga Mountain is determined using these two methods. The changes in soil phosphorus bioavailability along the 120-year-old chronosequence are assessed based on comparisons of the results obtained by these two methods. The results indicate that Hedley sequential fractionation technique shows a greater ability to determine soil bioavailable phosphorus(Resin-P and NaCHO3-P), while XANES is effective in distinguishing phosphorus bound by metal compounds. In the chronosequence, Ca- and Al-bound phosphorus were derived mainly from primary minerals, whose phosphorus contents decreased within 120 years of moraine weathering and soil development. The content of soil bioavailable phosphorus increased rapidly after 30 years since deglaciation. The increasing phosphorus bioavailability promoted the colonizing and primary succession vegetation.