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901.
Yuta Endo Atsushi Ohsawa Mizuki Yamaguma 《International journal of occupational safety and ergonomics》2019,25(1):35-39
We investigated the charge generated on bedclothes (cotton and polyester) during bedding exchange with different humidities and the ignitability of an alcohol-based hand sanitizer (72.3 mass% ethanol) due to static spark with different temperatures to identify the hazards of electrostatic shocks and ignitions occurring previously in medical facilities. The results indicated that charging of the polyester bedclothes may induce a human body potential of over about 10?kV, resulting in shocks even at a relative humidity of 50%, and a human body potential of higher than about 8?kV can cause a risk for the ignition of the hand sanitizer. The grounding of human bodies via footwear and flooring, therefore, is essential to avoid such hazards (or to reduce such risks). 相似文献
902.
Spatial and temporal trends of nitrate,chloride, and bromide concentration in an alluvial aquifer,North‐Central Texas,USA 下载免费PDF全文
《环境质量管理》2018,27(4):79-86
The Seymour aquifer consists of unconfined outcrops of sand and gravel in a semiarid, agricultural region of north‐central Texas in the United States of America. Most water samples collected from the aquifer in 2015 had nitrate concentrations above the drinking water standard of 44.3 milligrams per liter (mg/L). Generally, areas with high nitrate concentration in 2010 remained high in 2015, although the median dropped by 3.9 mg/L. The largest decreases in nitrate concentration—up to 97 mg/L (60%)—were observed in wells with depths less than the median of 13.1 meters (m). However, other wells, including depths above and below the median, showed increases in nitrate concentration of up to 40 mg/L (42%). In 2015, chloride concentrations in six wells exceeded the secondary contaminant level of 250 mg/L, and one well had a chloride concentration of 1,810 mg/L. Past and ongoing agricultural practices, including cultivation of native grassland, application of fertilizer, and irrigation with nitrate‐contaminated groundwater, help sustain overall high nitrate concentrations within the aquifer. Local conditions governing nitrogen inputs and dilution result in significant improvement or worsening of the nitrate problem over relatively short timeframes. The pumping of groundwater from the aquifer may facilitate mixing with groundwater of increased salinity that has been affected by the dissolution of evaporites in underlying Permian bedrock. 相似文献
903.
Antonio Roman-Alcalá 《Local Environment》2018,23(6):619-634
Food sovereignty movements (FSMs) globally have sought to rearrange relations between land, power, state actions and societal forces outside the state, towards a new ideal of democratised, egalitarian and ecological food systems. The question of how best to reach this ideal has vexed movements and scholars alike, with many anti-capitalist theorists proposing that because of the historical dedication of states to maintaining unequal and unsustainable capitalist relations, change must be pursued outside and against the state rather than through it (i.e. through “autonomism”). Yet, analysis of FSMs globally shows that autonomism is relative, partial and best seen as an aspirational ideal rather than a fixed dogma. This paper deepens this insight by analysing a case within the United States where a local direct action group promoted food sovereignty by illegally occupying public land. The case shows how even apparently autonomist movements can through influence on state and societal actors contribute to state-based “policy currents” that flow in the direction of food sovereignty. This mutual codetermination by actors in and out of state institutions of the possibility and shape of “policy currents” renders state–society relations as important, even to those interested in (relative) autonomism. This paper thus leaves behind dichotomous interpretations of (and recommendations for) FSMs vis-à-vis autonomism, in order to unpack the influence (in thought) and impact (in action) of autonomist tendencies in food sovereignty construction. 相似文献
904.
Haley Stanko 《Local Environment》2018,23(4):468-484
In 2008, the city of Philadelphia made increasing healthy food access a priority for sustainable development. Recognising that almost 25% of the population are considered food insecure, government agencies, non-governmental organisations and community leaders sought to increase food access through increasing food production and access to land in the city. Urban agriculture has gradually been incorporated in sustainability narratives in the past decade, both providing a platform for advocates to inform on policymaking, and potentially stripping away the political and activist origins of gaining access to food, land and green spaces in the city. In this paper, we argue that the depoliticising of urban agriculture advocacy through its incorporation in sustainability planning may serve to increase existing inequities in the city. Focusing on the policy-making scale, we examine measures enacted under the Philadelphia Greenworks Sustainability Plan to facilitate urban agriculture in the city. Our preliminary findings suggest that the processes by which urban agriculture gains acceptance demonstrate a disconnect in urban agriculture advocacy and policymaking and further work is needed to understand the impacts of the formalising of urban agriculture in Philadelphia. 相似文献
905.
906.
创新是大型游乐设施占领市场的核心竞争力,但创新也容易引发各类问题及不确定性,特别是涉及游乐设备可维护性方面,更容易在创新过程中忽视。本文以国外设备供应商生产的“自由落体”游乐设备的故障入手,从研究直流电机故障机理、维修方案以及设计维保建议等几个方面,提出提升直流电机可维护性的举措,主张行业的设计人员不但要聚焦大型游乐设施的趣味性,也要更多关注如何提高大型游乐设施的可靠性、可维护性。 相似文献
907.
应急物资储备库是应急救援的重要载体,储备库选址是否科学合理决定着整个应急公共服务体系的成效,而传统遗传算法在研究储备库选址与物资调配相结合的问题上存在局限性。针对这一问题,从需求点及应急设施服务质量视角构建基于覆盖满意度和经济性的应急设施选址与物资调配优化模型,并根据模型设计自适应遗传算法(AGA),结合储备库实际情况采取具有方向性的初始群体生成法提高搜索速度,设计自适应交叉与变异算子使AGA能够在进化速度与解的质量之间进行权衡,并获得全局最优解。结果表明,该算法能跳出局部最优从而获得最优的选址-分配方案,可为应急管理部门和决策机构的应急设施选址规划及应急物资分配提供理论依据和决策参考。 相似文献
908.
Michael G. Dosskey Zeyuan Qiu Yang Kang 《Journal of the American Water Resources Association》2013,49(6):1270-1283
Targeted placement of vegetative buffers may increase their effectiveness for improving water quality in agricultural watersheds. The use of digital elevation models (DEMs) enables precise mapping of runoff pathways for identifying where greater runoff loads can be intercepted and treated with buffers. Five different DEM‐based targeting indexes were compared and contrasted for the degree to which they identify similar locations in watersheds: Flow Accumulation [S.K. Jenson and J.O. Domingue (1988). Photogrammetric Engineering and Remote Sensing 54:1593], Wetness Index [I.D. Moore, R.B. Grayson, and A.R. Ladson (1991). Hydrological Processes 5:3], Topographic Index [M.T. Walter, T.S. Steenhuis, V.K. Mehta, D. Thongs, M. Zion, and E. Schneiderman (2002). Hydrological Processes 16:2041], and the Water Inflow and Sediment Retention Indexes [M.G. Dosskey, Z. Qiu, M.J. Helmers, and D.E. Eisenhauer (2011b). Journal of Soil and Water Conservation 66:362]. The indexes were applied in two different watersheds, one in New Jersey and one in Missouri. Results showed that they all tend to target similar locations in both watersheds which traces to the importance of larger contributing area to the rankings by each index. Disagreement among indexes traces to other variables which enable more accurate targeting under particular hydrologic circumstances. Effective use of these indexes poses special challenges, including selecting an index that better describes the hydrologic circumstances in a watershed and is simple enough to use, ensuring the accuracy of the DEM, and determining a maximum index value for the appropriateness of vegetative buffers. When properly applied, each index can provide a standardized basis and effective spatial resolution for targeting buffer placement in watersheds. 相似文献
909.
R. K. Sinha 《国际发展与全球生态学杂志》2013,20(4):278-284
SUMMARY In India, since ancient times, several members of the flora and fauna have been identified with particular personalities of the Hindu pantheon and are worshipped. Many wild animals, such as tigers, lions and elephants, and birds such as the peacock, owl and swan have been revered as the vehicles of Gods and Goddesses and worshipped. Several trees, such as mango, coconut, khejri, emblica, tamarind, ashoka, madhuca and wood apple, and herbs such as basil are considered highly sacred and worshipped. This belief and these practices continue in one form or another even today in certain sections of Indian society, particularly the rural folk and the aboriginal tribes living in the forest. Nature worship is a form of tribal belief and the faith of these laymen has helped to conserve many natural ecosystems in India. They have preserved many pristine forests—called ‘sacred groves’ in their original forms. Sacred groves are rich in biodiversity. They are the last refuge of the rare flora and fauna which have otherwise disappeared from the modern world. Sacred groves have become part of the ‘biosphere reserves’ of India. 相似文献
910.
Zhang Baolei 《中国人口.资源与环境(英文版)》2008,6(3):83-89
The Three Gorges Project attracts worldwide attention because of the Three Gorges migrants, and the agriculture of the Three Gorges Reservoir Area is a foundation for the development of the Three Gorges migrants. The Three Gorges Reservoir Area is situated at the mountainous area with bad agricultural development conditions and relatively low levels of development. As a result, the large-scale migration fias special influence on its agricultural development, which has attracted much attention. The paper analyzes influence that the migrants have forced on its agricultural development based on the scientific data, and makes some explorations on the models that are suitable for the development of mountainous agriculture in the Three Gorges Reservoir Area. 相似文献