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991.
王震  孙德智  高明 《环境工程》2010,28(5):102-106
随着我国废塑料资源化利用技术的不断发展,其资源化过程中的环境问题也日益显现。以生命周期评价为研究方法,对废聚苯乙烯共焦化过程的环境影响进行评价。研究结果表明:废聚苯乙烯共焦化过程对酸化、烟尘和粉尘、全球变暖3类环境问题的影响较大,分别占了总影响的34.0%、27.5%和23.3%。从共焦化过程的3个阶段来看,入炉炼焦阶段的环境影响最大,其次是混合颗粒制备阶段和PS颗粒制备阶段,对炼焦阶段环境污染的控制是废塑料共焦化技术发展的关键。  相似文献   
992.
酸性橙Ⅱ废水催化铁内电解法脱色研究   总被引:5,自引:0,他引:5  
对催化铁内电解法处理酸性橙Ⅱ废水进行了研究,考察了进水pH、搅拌速率、进水酸性橙Ⅱ浓度、铁铜比、支持电解质浓度、进水温度等因素对脱色效果的影响。在最优反应条件下,酸性橙Ⅱ的去除率大于98%,COD的去除率大于76%。催化铁内电解法对酸性橙Ⅱ的去除非常有效,且有较宽的pH适应范围。  相似文献   
993.
研究了有机质和CaCO3。对发育于花岗岩和第四纪红色粘土母质上的红壤的交换性铝的影响。结果表明,在用H2O2去除土壤中的有机质后,交换性铝的含量随有机质的降低而降低,但降低的速度不均匀,由慢到快似有一个“突跃”。而在向土壤中添加有机质的研究结果则表明,交换性铝的含量随有机质的增加而增加;在增加的过程中由快到慢,达到极点后,有机质含量再增加,交换性铝反而下降。在相同的土壤环境中,由于作物品种不同,施用等量的CaCO3(或石灰粉)对土壤交换性铝的含量及作物产量的影响不同,而且差异显著。  相似文献   
994.
水中痕量氰化物的反相流动注射-分光光度测定   总被引:5,自引:0,他引:5  
采用巴比土酸--吡啶(BA-P)反相流动注射分光光度法测定了水中痕量易释放氰化物和包括易释放氰化物和络合氰化物在内的无机总氰化物。将BA-P溶液注入到PH6.2NaH2PO4-NaOH缓谁氰胺-T溶液和预蒸馏水样的混合流中,在λmax580nm处对反应形成的晓紫色聚亚早基染料进行分光光度检测生为0.02~0.90mg/L,CN^-。检测限为0.003mg/L,测定频率为30次/h,本法灵敏度高,选  相似文献   
995.
根据美国道化学公司的火灾爆炸危险度评价原理,采用单元危险快速排序法,对锦州石化公司的催化裂化装置的火灾爆炸危险性进行综合评价。  相似文献   
996.
在社会主义市场经济条件下如何做好企业的环境保护工作是目前企业环保部门需要探讨的重要问题,通过阐述市场经济对企业环境保护产生的积极影响,分析了当前企业环保的基本状况和存在的问题,并提出了目前企业环保改革的思路。  相似文献   
997.
Mass media worldwide has contributed to increasing awareness of the illegal wildlife trade and its significant impact on wildlife conservation. We used mass media coverage as a proxy for macro-level public opinion to analyze the media framing of elephant ivory in 6394 Chinese newspaper articles published from 2000 to 2021 and thus determine the effects of wildlife policies on public opinion. We focused on 2 events: the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) approval of China as a trading partner in the purchase and import of ivory stockpiles from Africa in July 2008 and the Chinese government's announcement of a domestic ivory ban in December 2016. Using latent Dirichlet allocation topic modeling, we identified 8 topics about elephant ivory and grouped them into 3 frames: ivory arts and culture, ivory crimes, and elephant conservation. Over the last 2 decades, topics related to ivory crimes remained the most prevalent in news articles. Topics about ivory arts and culture showed a significant shift in media salience before and after the 2 events (from 0.44 to 0.19 and from 0.08 to 0.15, respectively, p < 0.05), whereas the other 2 frames did not change significantly. Contrary to popular belief, our results indicated that Chinese macro-level public opinion on ivory had become more negative following the CITES approval of ivory importation and less negative after the ivory ban announcement, at least for certain periods. The relationship between mass media, public opinion, and wildlife trade policies is complex and requires further examination of the sociopolitical dynamics that influence media narratives. Our results showed the value of topic modeling in monitoring and assessing media representations of wildlife issues in the era of big data. Conservationists should remain vigilant of mass media coverage and collaborate with media practitioners to produce comprehensive narratives on wildlife issues if resources permit.  相似文献   
998.
Wang  Zhenyao  Li  Xuan  Siddiqui  Muhammad Ahmar  Liu  Huan  Zhou  Ting  Zheng  Lei  Huang  Siyu  Gao  Li  Lin  Carol Sze Ki  Wang  Qilin 《Environmental Chemistry Letters》2023,21(5):3023-3040
Environmental Chemistry Letters - Anaerobic digestion is a promising technology for energy recovery from secondary sludge, yet the presence of humic substances in wastewater limits anaerobic...  相似文献   
999.
● Emotional responses to visibility-reducing haze was assessed in a controlled lab. ● Valence and arousal have non-linear responses to pollution-caused low visibility. ● Repetitive exposure aggravates negative emotions in severely polluted conditions. ● Emotional bias to pollution relates with gender, decisiveness, attitude to clean air. A growing number of studies have shown that impaired visibility caused by particulate matter pollution influences emotional wellbeing. However, evidence is still scant on how this effect varies across individuals and over repetitive visual exposure in a controlled environment. Herein, we designed a lab-based experiment (41 subjects, 6 blocks) where participants were presented with real-scene images of 12 different PM2.5 concentrations in each block. Emotional valence (negative to positive) and arousal (calm to excited) were self-rated by participants per image, and the response time for each rating was recorded. We find that as pollution level increases from 10 to 260 µg/m3, valence scores decrease, whereas arousal scores decline first and then bounce back, following a U-shaped trend. When air quality deteriorates, individual variability decreases in hedonic valence but increases in arousal. Over blocks, repetitive visual exposure increases valence at a moderate pollution level but aggravates negative emotions in severely polluted conditions (> 150 µg/m3). Finally, we find females, people who are slow in making responses, and those who are highly aroused by clean air tend to express more negative responses (so-called negativity bias) to ambient pollution than their respective counterparts. These results provide deeper insights into individual-level emotional responses to dirty air in a controlled environment. Although the findings in our pilot study should only be directly applied to the conditions assessed herein, we introduce a framework that can be replicated in different regions to assess the impact of air pollution on local emotional wellbeing.  相似文献   
1000.
● Present a general concept called “salinity exchange”. ● Salts transferred from seawater to treated wastewater until completely switch. ● Process demonstrated using a laboratory-scale electrodialysis system. ● High-quality desalinated water obtained at ~1 mL/min consuming < 1 kWh/m 3 energy. Two-thirds of the world’s population has limited access to potable water. As we continue to use up our freshwater resources, new and improved techniques for potable water production are warranted. Here, we present a general concept called “salinity exchange” that transfers salts from seawater or brackish water to treated wastewater until their salinity values approximately switch, thus producing wastewater with an increased salinity for discharge and desalinated seawater as the potable water source. We have demonstrated this process using electrodialysis. Salinity exchange has been successfully achieved between influents of different salinities under various operating conditions. Laboratory-scale salinity exchange electrodialysis (SEE) systems can produce high-quality desalinated water at ~1 mL/min with an energy consumption less than 1 kWh/m3. SEE has also been operated using real water, and the challenges of its implementation at a larger scale are evaluated.  相似文献   
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