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21.
微生物强化采油技术研究现状及应用前景 总被引:1,自引:0,他引:1
介绍了微生物强化采油技术的基本概念、机理和发展现状,讨论了该技术的研究方法、优点及应用条件,并展望了微生物强化采油技术的应用前景。 相似文献
22.
将具有氧化性的有机废水池作为电池的阳极,具有还原性的重金属废水池作为电池的阴极,利用微生物燃料电池( MFC)同时处理有机废水和重金属废水.结果表明,利用铜离子溶液作阴极, MFC最大电压可达到0.277 V,最大功率密度为33.49 mW/m2,COD的去除率为31.6%,铜的去除率可达42%;利用银离子溶液作阴极,MFC最大电压可达到0.311 V,最大功率密度为42.21 mW/m2, COD的去除率为64.6%,银的去除率可达78%.即不管是从产电角度还是从废水处理角度考虑,都是以银离子废水作阴极优于铜离子. 相似文献
23.
王宁 《中国资源综合利用》2005,(4):25-26
利用制药厂的废水生产农用测土配方肥,方法可行,生产操作简单,做到废物循环利用,实现了经济、社会和环境三效益的统一. 相似文献
24.
简要介绍了国内外盆栽花卉培养介质,分为天然壤土堆肥和无壤土堆肥,其施肥方式也有区别;对盆栽花卉活力剂研究特点进行了综述,根据我国盆土实际情况,研制出了盆栽花卉活力剂。 相似文献
25.
Because of tensions on fossil energy and phosphorus markets, the rise in fertilizer prices observed during the last decades may continue in the future, putting into question production pathways relying heavily on crop intensification. To evaluate how, in this context, economic choices may alter crop yields, we first construct different fertilizer price scenarios to 2050 based on an econometric relation with oil and gas prices. Other possible scenarios, such as the continuation of historical trends, are also considered. The resulting changes in fertilizer price range between +0.8% and +3.6% per year over the 2005–2050 period. These scenarios are tested in a global land‐use model incorporating an endogenous representation of the land–fertilizer substitution. We find that the supply‐side response to rising fertilizer prices could lower crop yields in 2050 from ?6% to ?13%, with a corresponding increase in global cropland area ranging between 100 and 240 Mha if the demand for food and nonfood products has to be met. The sensitivity of these results is tested with regard to assumptions on food consumption, change in potential yield and nutrient use efficiency. 相似文献
26.
由磷肥企业副产氟硅酸制备氟化钠的研究 总被引:1,自引:0,他引:1
郭伟杰 《中国资源综合利用》2007,25(11):4-6
重点介绍了以磷肥企业副产氟硅酸为原料制备氟化钠的新工艺。首先用氨水氨化脱硅得到氟化铵溶液,再向氟化铵溶液加氯化钠合成氟化钠。对影响反应的温度、时间、物料配比等因素进行了探讨,得出具体工艺为:(1)氨化反应:H2SiF6浓度在12%~14%之间,氨水过量25%,反应温度为60~70℃,反应时间120min。(2)氟化钠合成:氯化钠过量15%~20%,反应温度85~90℃。产物氟化钠纯度大于98%,收率大于80%。 相似文献
27.
Seon-Woong Kim 《Applied economics letters》2018,25(4):229-233
High fertilizer price volatility makes production planning and inventory management difficult, so accurate fertilizer price forecasts would be beneficial. This article evaluates commercial forecasts for urea and diammonium phosphate (DAP) prices based on forecast accuracy and optimal forecast properties. Most forecasts pass the tests, but forecasts for the US New Orleans urea and the US Gulf DAP markets, in particular, do not and thus show potential to be improved. 相似文献
28.
29.
This paper provides a review and evaluation of different food‐risk prioritization and management frameworks that have been developed by governmental food‐safety authorities, regulatory agencies and non‐governmental institutions worldwide. It emphasizes the need for a new science‐ and risk‐based system approach to microbial risk prioritization. We find that most studies and projects argue for a systematic and multi‐disciplinary approach to risk prioritization but nevertheless lack it. Human and public health issues have constituted the core focus of food‐risk analysis in food‐borne risk prioritization studies, where the majority of studies use the concept of disease burden. Even though it is widely recognized that economic and market‐level impacts of microbial hazards and preventive interventions to reduce food‐borne risks are crucial to the performance of industries and markets, they are almost never accounted for in risk prioritization frameworks. 相似文献
30.
Julius J. Okello Carl-Johan Largerkvist Marther W. Ngigi Nancy Karanja 《国际农业可持续发展杂志》2013,11(2):183-199
Past studies of the use of soil fertility management strategies by farmers usually model input use decisions based on the neoclassical utility/profit maximization principle in which farmers use soil fertility management inputs primarily to increase revenues and profits. However, there is, to date, no study that explains exactly how this decision-making process occurs and the role which personal values play in driving the choice of soil fertility management inputs. This article systematically maps the relationship between choice of soil fertility management strategy (attributes), its outcomes (consequences) and the personal values that motivate the choice. It specifically uses the means-end chain approach to construct hierarchical value maps that relate the attributes to consequences, and ultimately to the personal values. The study finds that the use of soil fertility management strategies by peri-urban fresh vegetable growers is driven by five personal values, namely happiness, comfortable life, independence, good/healthy life and achievement of life goals. It also finds that while farmers seek to increase profit (hence incomes), profit maximization is not the end driver of the use of soil fertility management inputs. It concludes that a lot more goes into farmers’ decision-making process relating to the use of soil fertility management practices than can be explained by the neoclassical profit/utility maximization principle. The study discusses the policy implications of these findings. 相似文献