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941.
ABSTRACT

This paper examines the provincial government of British Columbia's recent proposal of building a Liquefied Natural Gas (LNG) industry, in which natural gas extracted through hydraulic fracturing will be liquefied and then exported to Asian markets. Drawing upon the growing literature on energopower, petro-state, and petro-culture, selected texts and images from “LNG in BC”—the project's official branding website—were analyzed through a multimodal critical discourse analysis. The results reveal two primary strategies of legitimation: the first emphasizes the economic benefits of LNG development in terms of employment and taxation revenues; the second defines LNG as a means of strengthening B.C.’s environmental leadership. The second narrative depends heavily upon the symbolic values of natural gas, contrasting its “clean” appearance (as a colorless and odorless gas) with the material density and “toxic sensuality” of other “dirty” fossil fuels (such as coal, oil, and bitumen). The website also presents a linear and simplified “storyline” of the generation of LNG which emphasizes the simple, “clean” process of liquefaction to distract attention from the ecological and health risks of hydraulic fracturing.  相似文献   
942.
热解温度对污泥生物炭的表面特性及重金属安全性的影响   总被引:4,自引:0,他引:4  
以一套中试干燥热解一体化处理设备,采用热解工艺,在300~600℃范围内对污水处理厂产生的剩余污泥进行了批处理,得到了系列污泥生物炭产品,并对其表面电荷、FT-IR图谱等进行了测试,对污泥及生物炭的重金属总量和DTPA可提取态进行了比较分析。研究表明,热解温度会影响生物炭表面电荷分布,而且在400℃时表面电荷分布最均匀。经热解反应后,污泥中的重金属总量虽然得到了一定程度的富集,但Pb,Zn,Cu,Fe和Mn 5种重金属的DTPA-可提取态的含量大幅度降低,因此,污泥生物炭中的重金属被惰性化,降低了环境风险。  相似文献   
943.
采用悬浮结晶法处理喹乙醇生产废液,考察了成冰率(冰晶融化后的体积占原水总体积的百分比)对废液COD、氨氮、TN和电导率去除效果的影响。在一级冷冻成冰率45%的条件下,经过三级冷冻处理后,三级出水的COD、氨氮、TN和电导率的去除率分别为99.4%、98.7%、98.5%和98.2%,一级浓缩液的COD、氨氮和TN的浓缩比分别为1.6、1.5和1.5;在一级冷冻成冰率80%的条件下,每一级出水的各项指标的去除率均有所下降,三级出水的COD、氨氮、TN和电导率的去除率分别为98.6%、98.3%、97.1%和95.9%,但一级浓缩液的浓缩比明显提高,COD、氨氮和TN的浓缩比分别为2.7、2.2和2.4。成冰率为80%时一级浓缩液的热值为7 449 J/g,在焚烧过程中可以依靠自身热量维持燃烧,不需要添加辅助燃料,减少焚烧处理的成本。  相似文献   
944.
This study examines what happens when contentious lay citizens harness the technical-ecological repertoire of experts as means of challenging nature conservation policy. The causes, manifestations, and implications of this phenomenon are elucidated through a critical discourse analysis. The case study is based on the wolf reintroduction project in Europe, with particular focus on Sweden, using illegal hunting discussions as a point of entry within the hunting community. It reveals the deployment of three topoi, which are defined as stock arguments situated within a discourse. Analysis shows how while some topoi often incur short-term gains in the debate because of their scientific guise, they are fundamentally relegated as folk science (or “barstool biology”) by government experts and, in some cases, contribute to the further marginalization of other knowledges. Acquiescence to this discourse is shown to greatly impede the debate. Finally, the study shows how lack of trust in the public dialog, which hunters openly recognize to be colonized by ecological expertise, results in increasingly noncommunicative forms of resistance toward policy.  相似文献   
945.
利用WPS宽范围粒径谱仪对朱日和春季0.01~10μm的沙尘气溶胶观测资料,以及20m梯度塔气象要素资料,对沙尘天气日和非沙尘天气日的气溶胶浓度、谱分布以及输送特性进行了个例研究.结果表明:沙尘气溶胶浓度有明显的日变化特征,不同粒径段粒子的变化特征有所不同;沙尘气溶胶浓度在沙尘天气和非沙尘天气存在较大差别,粒径越大,这种差别越明显;气象要素对沙尘气溶胶浓度的分布有较大的影响,风速、气温、相对湿度与不同粒径段粒子的相关性不同;沙尘暴过程对不同粒径段粒子的输送特性不同,不同粒径段对应的输送距离和输送量有较大差别.  相似文献   
946.
An estimation of the indoor background radiation dose distribution was carried out in dwellings of eleven villages located within and around the uranium mineralization area of Kylleng-Pyndensohiong, Mawthabah in West Khasi Hills District of Meghalaya, India. The ambient indoor gamma radiation level was monitored using Thermo Luminescence Dosimeters (TLDs) while the indoor radon and thoron concentration was measured using twin-cup dosimeters employing Solid State Nuclear Track Detectors (SSNTDs). Results obtained from the study reveals that the local inhabitants of villages located close to the mining site receive higher doses than those inhabitants of villages located at a much farther distance from the mining site. The average total annual effective dose was found to be varying from 1.2 mSv y−1 in the village of Langpa to 3.4 mSv y−1 in the village of Nongbah Jynrin. The data obtained will serve as a reference in documenting changes to environmental radioactivity if mining is to be carried out in the future.  相似文献   
947.
A/O膜生物反应器处理高浓度氨氮废水试验研究   总被引:4,自引:0,他引:4  
对A/O膜生物反应器处理高浓度氨氮废水进行了研究,着重考察硝化液回流比和C/N对系统脱氮效能的影响.研究表明,当硝化液回流比为2、C/N为6时.系统对COD、氨氮、TN的平均去除率分别达96.17%、97.76%、76.29%;A/O膜生物反应器稳定运行期间,氨氮容积负荷去除量与进水氨氮容积负荷呈现良好的线性关系;当A/O膜生物反应器内MLSS稳定在9~13 g/L时,上清液COD较低,膜压差增长缓慢.  相似文献   
948.
COD浓度和进水流量比对一体化工艺脱氮除碳的影响   总被引:1,自引:1,他引:0  
保持进水总流量不变,以一定流量比同时从缺氧区和厌氧区进水,探讨了不同进水流量比(R=Q/Q)和进水COD浓度对中心岛式一体化OCO工艺脱氮除碳的影响。研究结果表明,进水COD浓度和进水流量比Rs对COD的去除效果影响不大,出水COD浓度一直稳定在50 mg/L以下,去除率在92%以上;进水COD浓度和进水流量比Rs共同决定着系统TN的去除效果,进水COD浓度为100 mg/L、200 mg/L时,TN去除率随着进水流量比Rs的减小呈增加的趋势;当进水COD浓度为 300 mg/L时,TN去除率随着进水流量比Rs的减小呈先升高后降低的趋势,在进水流量比Rs为3∶1时TN去除率最高,达到87%。  相似文献   
949.
The results of an investigation characterizing the nutrients and suspended solids contained in stormwater from Kranji Catchment in Singapore are reported in this paper. Stormwater samples were collected from 4 locations and analyzed for the following eleven analytes: TOC, DOC, TN, TDN, NH4+, NO2 + NO3 (NOx), TP, TDP, OP, SiO2 and TSS. Stormwater was sampled from catchments with various proportions of rural and urban land use, including forested areas, grassed areas, agricultural and residential and commercial areas. The event mean concentrations (EMCs) of nutrients and TSS from sampling stations which have agricultural land use activities upstream were found to be higher. Comparison of site EMCs (SMCs) with published data showed that the SMCs of the nutrients and TSS are generally higher than SMCs reported for forested areas but lower than published SMCs for urban areas. Positive correlations (p < 5%) were found between loading and peak flow at locations most impacted by ubanisation or agricultural activities. Correlation between loading and rainfall variables was less distinct. EMC was found to correlate less with rainfall and flow variables compared to pollutant loading. Unlike loading, no consistent pattern exists linking EMC to any particular storm or flow variable in any of the catchments. Lastly, positive correlations were obtained between the particulate forms of nitrogen and phosphorus and TSS.  相似文献   
950.
采用AIC1000型空气负离子浓度测试仪,对西湖综合保护工程实施范围内的不同绿地进行了空气负离子浓度测定,结果表明,不同绿地空气负离子浓度排序依次为:乔灌草型〉疏林草地型〉滨水绿地型〉硬质铺地型,且滨水绿地型样地与硬质铺地型差异较小。与此同时,西湖风景区的空气负离子浓度显著高于城市中心区。  相似文献   
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