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521.
ABSTRACT

Natural history films use technological mediations to frame aspects of nature so as to communicate information, in part through engendering particular viewer affects. As an entertainment industry embedded in capitalist social relations and concerned with competition for finance and ratings, natural history film-making is also a search for “the money shot” – associated with extremes including rarity, sensational behavior, and otherwise un(fore)seen views. I highlight this sensationalizing impetus through ethnographic fieldwork conducted at the biannual UK Wildscreen film festival in 2010. Here, wildlife films were frequently presented as action dramas with a rhythm of anticipation, climax and satisfaction. I argue that, through stimulating significantly disconnective affects, such framing may work against composition of a caring ecocultural ethics that entwines human with more-than-human natures and futures; and that this tendency parallels the similarly disconnecting effects documented for pornographic film. In contrast, I engage with the differently constructive frames guiding the low budget, open access, activist film Green, which, perhaps paradoxically given the thrust of much of the natural history film industry, won the prestigious WWF Gold Panda Award at Wildscreen 2010. I follow framing theorist George Lakoff to emphasize that since cognition is both embodied and embedded in diverse inter-relationships, affective registers generating mimetic connection are as significant in communicating information regarding “the environment” as the text and words by which nature might be framed. I conclude that attention to affective registers and embodied (dis)connections in natural history film may enhance a turning of capitalist spectacle against itself, so as to work more effectively in service to the composition of abundant socionatural futures.  相似文献   
522.
Raised beds are used to produce some high-value annual fruit and vegetable crops such as strawberry in California (CA) and tomato in Florida (FL), USA. Pre-plant soil fumigation is an important tool to control soil-borne pests in the raised beds. However, fumigant emissions have detrimental environmental consequences. Field trials were conducted to evaluate emissions of 1,3-dichloropropene (1,3-D) and chloropicrin (CP) in two different production systems with raised beds covered by different tarps. In the CA trial, InLine (60.8% 1,3-D and 33.3% CP) was drip-applied at 340 kg ha−1 to 5 cm deep in the beds (30 cm high and 107 cm wide) tarped with polyethylene (PE) or virtually impermeable film (VIF). In the FL trial, carbonated Telone C35 (63.4% 1,3-D and 34.7% CP) was shank-applied at 151 kg ha−1 to 20 cm deep in the beds (22 cm high and 76 cm wide) tarped with totally impermeable film (TIF). Emissions from tarped beds relative to furrows were contrary between the two trials. For the CA trial, the emission was 47% of applied 1,3-D and 27% of applied CP from PE tarped beds and 31% of applied 1,3-D and 15% of applied CP from VIF tarped beds, while that from uncovered furrows was <0.4% for both chemicals in both fields. In the FL trial, only 0.1% 1,3-D was emitted from the TIF tarped beds, but 27% was measured from the uncovered furrows. Factors contributing to the differences in emissions were chiefly raised-bed configuration, tarp permeability, fumigant application method, soil properties, soil water content, and fumigant carbonation. The results indicate that strategies for emission reduction must consider the differences in agronomic production systems. Modifying raised bed configuration and fumigant application technique in coarse textured soils with TIF tarping can maximize fumigation efficiency and emission reduction.  相似文献   
523.
A field experiment was conducted to compare two plastic mulches and two application rates on surface emissions and subsurface distribution of methyl bromide (MBr) in field beds in Florida. Within 30 minutes after injection of MBr to 30 cm depth, MBr had diffused upward to soil surface in all beds covered with polyethylene film (PE) or virtually impermeable film (VIF) and applied at a high rate (392 kg/ha) and a low rate (196 kg/ha). Due to the highly permeable nature of PE, within 30 minutes after injection, MBr volatilized from the bed surfaces of the two PE-covered beds into the atmosphere. The amount of volatilization was greater for the high rate-treatment bed. On the other hand, volatilization of MBr from the bed surfaces of the two VIF-covered beds were negligible. Volatilization losses occurred from the edges of all the beds covered with PE or VIF and were greater from the high rate-treatment beds. Initial vertical diffusion of MBr in the subsurface of the beds covered with PE or VIF was mainly upward, as large concentrations of MBr were detected from near bed surfaces to 20 cm depth in these beds 30 minutes after injection and little or no MBr was found at 40 cm depth. The two VIF-covered beds exhibited greater MBr concentrations and longer resident times in the root zone (0.5–40 cm depth) than corresponding PE-covered beds. Concentrations of MBr in the root zone of the high rate-treatment beds were 3.6–6.1 times larger than the low rate-treatment beds during the first days after application. In conclusion, VIF promoted retention of MBr in the root zone and, if volatilization loss from bed edges can be blocked, volatilization loss from VIF-covered beds should be negligible.  相似文献   
524.
利用一种新型有机复合填料作为生物滤床中微生物的附着载体,接种经过驯化筛选的专性甲苯降解菌,填装于生物过滤塔中净化低浓度甲苯气体。研究了新型有机复合填料在长期运行时的情况,考察了进气流量、入口浓度、床层温度和填料湿度对生物滤床的影响,最终经过优化得出,此种填料的生物滤床能够为微生物提供良好的附着生长环境,并能保持滤床的高效稳定运行,当进气流量为0.4 m3/h,入口浓度为400 mg/m3,床层温度为30℃,填料湿度为50%时,生化去除量达到30.6 g/(m3.h),并且在此条件下滤床具有良好的耐冲击性能。  相似文献   
525.
微生物的异化Fe(Ⅲ)还原是一种能够利用Fe(III)作为末端电子受体在无氧条件下氧化有机物的产能过程。结合这一特性,考察了在兼性厌氧/严格厌氧条件下Fe^0钝化膜作为Fe(111)源时的生物还原能力以及对N、P等营养元素的去除效果。结果表明,严格厌氧条件下微生物异化Fe(Ⅲ)还原能力较好,富集培养至7d,累计Fe(II)浓度达到最大,最大产生速率为98.69mg/(L·d),同时TP去除率高达97.1%以上。而体系对NH4-N、TN的去除相对滞后,培养至13d,去除率开始增大,最终分别达到86.6%和76.1%。这为装填有海绵铁+聚氨酯泡沫载体的SBBR中填料的原位再生问题提供了解决思路。  相似文献   
526.
张岩  魏少红  陈松涛 《化工环保》2013,33(3):276-280
通过电化学的方法将结晶紫聚合在玻碳电极表面制备聚结晶紫(PCV)膜修饰电极,并研究了对苯二酚和邻苯二酚在PCV膜修饰电极上的电化学行为。PCV膜修饰电极对对苯二酚和邻苯二酚的氧化有良好的电催化作用。在最佳的实验条件下,氧化峰电流在对苯二酚和邻苯二酚的浓度为4.0×10-6~2.8×10-4mol/L之间呈良好线性关系,对苯二酚和邻苯二酚的线性相关系数分别为0.9991和0.9823,检出限分别为6.2×10-7mol/L和9.0×10-7mol/L。PCV膜修饰电极具有良好的灵敏度、重现性和稳定性,可以应用于实际水样中两种物质的同时测定。  相似文献   
527.
刘庆辉 《环境技术》2012,37(1):41-45
本文介绍了环境试验方法、内容和应用范围,详细阐述了环境试验中环境应力引起的失效模式及其对塑料产品质量的影响。  相似文献   
528.
为解决高含盐废水降膜蒸发过程中液膜破裂产生的干区和结垢问题,采用高灵敏度的红外热成像仪实验研究了高含盐废水受热降膜破裂后的流动状态.结果表明,破裂降膜径向存在热Marangoni效应和溶质Marangoni效应.热Marangoni效应引起了液膜由侧而边缘向中心主流区的收缩,形成稳定的干区;而溶质Marangoni效应...  相似文献   
529.
废旧聚乙烯复合材料的制备与性能研究   总被引:1,自引:0,他引:1  
介绍了废旧聚乙烯复合材料的制备与性能。以废旧聚乙烯为原材料,通过与超细白炭黑进行纳米复合,制备高性能纳米复合材料;利用木粉、竹粉、稻糠等植物纤维与其进行木塑复合,制备环保型木塑复合材料;重点研究了多单体接枝共聚物在复合材料中的界面改性作用。  相似文献   
530.
肖思煜 《环境技术》2006,24(4):39-41
概述了紫外光固化涂料在汽车塑料部件、修补漆、面漆上的应用,并展望了紫外光固化涂料在汽车涂装上的发展趋势.  相似文献   
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