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541.
吴鑫 《中国安全生产科学技术》2013,(10):127-131
安全科技是经济社会安全发展的重要基石,是企业安全生产和人民生命财产安全的重要保障,是安全监管监察工作的重要支撑,是提高企业本质安全生产水平的根本途径。当前,我国安全科技工作即面临挑战,又面临重大机遇。加快安全科技转化为提升安全保障能力,要以科学发展、安全发展理念为指导,坚持企业为主体、市场为导向的原则,主要从实施安全科技“四个一批”、强化安全科技顶层设计、推广先进适用技术装备等方面进行努力探索。 相似文献
542.
Runoff and sediment losses from 27 upland catchments in Southeast Asia: Impact of rapid land use changes and conservation practices 总被引:5,自引:0,他引:5
C. Valentin F. Agus R. Alamban A. Boosaner J.P. Bricquet V. Chaplot T. de Guzman A. de Rouw J.L. Janeau D. Orange K. Phachomphonh Do Duy Phai P. Podwojewski O. Ribolzi N. Silvera K. Subagyono J.P. Thibaux Tran Duc Toan T. Vadari 《Agriculture, ecosystems & environment》2008,128(4):225-238
Rapid changes in upland farming systems in Southeast Asia generated predominantly by increased population pressure and ‘market forces’ have resulted in widespread land degradation that has been well documented at the plot scale. Yet, the links between agricultural activities in the uplands and downstream off-site effects remain largely unknown because of the difficulties in transferring results from plots to a larger scale. Many authors have thus pointed out the need for long-term catchment studies. The objective of this paper is to summarize the results obtained by the Management of Soil Erosion Consortium (MSEC) over the last 5 years from 27 catchments in five countries (Indonesia, Laos, Philippines, Thailand, and Vietnam). The purpose of the study was to assess the impacts of cultivation practices on annual runoff and erosion rates. Initial surveys in each catchment included topography, soils and land use. Monitoring included climatic, hydrologic and erosion (total sediment yield including bed load and suspended sediment load) data, land use and crop yields, and farmers’ income. In addition, new land management options were introduced through consultations with farmers and evaluated in terms of runoff and erosion. These included tree plantations, fruit trees, improved fallow with legumes, maize intercropped with legumes, planted fodder, native grass strips and agro-ecological practices (direct sowing and mulch-based conservation agriculture). Regressions analyses showed that runoff during the rainy season, and normalized runoff flow coefficient based on erosive rainfall during the rainy season (rainfall with intensity exceeding 25 mm h−1) increase with the percentage of the catchment covered by maize. Both variables decrease with increasing soil depth, standard deviation of catchment slope (that reflects terrain roughness), and the percentages of the catchment covered by fallow (regular and improved), tree plantations and planted fodder. The best predictors of sediment yield were the surface percentages of maize, Job's tears, cassava and footpaths. The main conclusions generated from this study were: (i) soil erosion is predominantly influenced by land use rather than environmental characteristics not only at the plot scale but also at the catchment scale; (ii) slash-and-burn shifting cultivation with sufficiently long rotations (1 year of cultivation, 8 years of fallow) is too often unjustly blamed for degradation; (iii) in its place, continuous cropping of maize and cassava promotes high rates of soil erosion at the catchment scale; (iv) conservation technologies are efficient in reducing runoff and total sediment yield at the catchment scale; (v) the adoption of improved soil management technologies by upland farmers is not a function of the degree of intensification of their farming system and/or of their incomes. The results suggest that if expansion of maize and cassava into already degraded upland systems were to occur due to increased demand for biofuels, there is a risk of higher runoff and sediment generation. A failure to adopt appropriate land use management strategies will result in further rapid resource degradation with negative impacts to downstream communities. 相似文献
543.
SMBR-IVCW系统处理高浓度综合污水 总被引:1,自引:0,他引:1
为了提高污水处理的质量和效率,将高效的生物处理技术--膜.生物反应器(SMBR)与生态净化技术--复合垂直流人工湿地(IVCW)进行有效复合而成的SMBR-IVCW复合系统应用于高浓度综合污水的高效处理与回用中.通过对不同水力负荷组合条件下SMBR-IVCW系统对污染物净化效果的比较,得到了该复合系统的较好水力组合条件.结果表明,SMBR-IVCW具有良好的净化功效及稳定性,SMBR单元在有机物的去除、硝化作用中起到主要贡献,而IVCW单元在反硝化脱氮、深度除磷等方面进一步补充,两者的有机结合能充分发挥各自的优势,并得到了较优的水力负荷组合条件:SMBR为1000L·d-1,IVCW为375mm·d~;在该条件下.SMBR-IVCW系统总停留时问为19.22h.处理后出水中CODcr、TP、NH 4-N浓度分别为11.0、0.086、0.44mg·L-1,均可达地表水环境质量Ⅲ类标准(GB 3838.2002).SMBR-IVCW系统在此类污水处理方面具有良好的潜力. 相似文献
544.
微生物处理有机污染物是一种费用低,效果好,无二次污染且操作简单的处理方法。综述了国内外几种微生物处理有机污染物技术的研究进展。 相似文献
545.
546.
DABWAN Ahmed H A IMAI Daizo KANECO Satoshi SENMATSU Isamu NAKAHAMA Katsuyuki KATSUMATA Hideyuki SUZUKI Tohru OHTA Kiyohisa 《环境科学学报(英文版)》2008,20(2)
A sintering technology for preparing porous materials from sea bottom sediments was developed for use in water purification. The purpose of the present study was to develop methods for converting the sea bottom sediments dredged from Ago Bay into value-added recycled products. The sintered products fabricated at 400℃ were found to be very effective adsorbents for the removal of heavy metals. 相似文献
547.
548.
厌氧发酵技术能较好地实现城市生活垃圾的资源化、无害化和减量化,是目前垃圾处理技术一个新的重要发展方向,而国内尚无运行的厌氧发酵处理厂。针对国外厌氧发酵技术的应用情况和发展趋势,侧重于从工程应用方面总结已建厌氧发酵处理厂的发酵技术,为我国厌氧发酵处理厂的建设和运行提供一定的技术支持。 相似文献
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