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染料厂、农药厂、制药厂等工业都会产生含有高浓度苯胺的废水,处理苯胺废水的方法较多,本文通过实验的方式着重研究了膜萃取法处理高浓度苯胺废水,并通过分析实验结果得出了相应结论。  相似文献   
364.
The high-temperature and high-pressure methanol one-step oxidation has been the primary process for the mass production of dimethoxymethane. However, the risk of explosion for this process is still not properly defined. This paper presents new results from the experimental study on the explosion characteristics, including the explosion pressure and the explosion limits for methanol/air mixtures with a variable oxygen level, under an initial pressure between 0.3 MPa and 0.75 MPa and at the initial temperature of 423 K. The upper explosive limits were found to increase along with the initial pressure. If the limits for normal air are known, the oxygen effect on flammability is predictable from the thermal balance method. With a correlation for the pressure effect and a method for the oxygen effect, we can have the flammable range predictable.  相似文献   
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ABSTRACT

Drought is defined, experienced, and communicated about in multiple ways. This case study examines individual definitions of drought (timing, impacts, and severity) and attitudes about climate change. Household surveys (n?=?120) were conducted in Cimarron County, Oklahoma and Union County, New Mexico using a stratified random sampling method to select farmers, ranchers, and town residents. Information about drought is primarily communicated between neighbors, friends, and family, as well as media and local governing agencies. Residents perceive the recent drought to be the worst drought on record, regardless of previous drought experiences. Residents reported widespread drought-related impacts on agriculture, environment, and society. Most residents see drought as cyclical and driven by natural causes, rather than human causes. We recommend adaptive drought communication engage more fully with identity, place, and history. Climate information should be presented in a relevant manner to diverse agricultural stakeholders with differing attitudes about climate change, management, and climate information.  相似文献   
367.
南江林 《火灾科学》2013,22(2):107-112
根据2002年至2010年我国群死群伤火灾的统计数据,分析了群死群伤火灾的总体形势、时空分布以及发生场所和起火原因的影响,得到了群死群伤火灾的发展趋势及其发生的规律和特点。结果表明,群死群伤火灾总体呈波动下降趋势,受经济因素影响明显;在发生时段上,年初和年末高于年中,晚上高于白天;在发生场所上,居住建筑发生的起数和死亡人数最多;在火灾原因上,电气火灾和用火不慎远远高于其他原因。  相似文献   
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This paper aims to investigate factors affecting public attitude towards the siting of locally unwanted land uses (LULUs) and to explore the possible strategies to resolve such conflicts. Three questionnaire surveys were undertaken in communities with different siting experiences and socio-economic profiles. Over 750 individuals were successfully interviewed in each study district. The three communities were found to share similar risk beliefs but show variations in the level of awareness of and response to LULUs. In communities with a disproportionate share of LULUs, many residents did not trust the government in handling LULU issues and thought that the siting process was unfair. The results of the binary logistic regression analysis show that people are likely to oppose the siting of a LULU in their community if they have a negative siting experience, do not perceive the need, accord a high risk to the facility and have a low level of trust in government. The resolution strategies preferred by the public are greater public participation and effective mitigation of risks and impacts, rather than provision of compensation and incentives. All these call for policy-makers to be sensitive to local concerns, engage the public in the process, communicate risks effectively and foster trust building.  相似文献   
369.
● Education and subsidy were effective interventions during short-term heat exposure. ● A new index was defined to evaluate the intervention performance. ● Blood pressure and sleep duration were more heat-sensitive for the elderly. Due to climate change, the heatwave has become a more serious public health threat with aging as an aggravating factor in recent years. There is a pressing need to detect the most effective prevention and response measures. However, the specific health effects of interventions have not been characterized on an individual scale. In this study, an intervention experiment was designed to explore the health effects of heat exposure at the individual level and assess the effects of different interventions based on a comprehensive health sensitivity index (CHSI) in Xinyi, China. Forty-one subjects were recruited randomly, and divided into one control group and three intervention groups. Interventions included education (Educate by lecturing, offering relative materials, and communication), subsidy support (offer subsidy to offset the cost of running air conditioning), and cooling-spray (install a piece of cooling-spray equipment in the yard). Results showed that systolic blood pressure (SBP) and deep sleep duration (DSD) were significantly affected by short-term heat exposure, and the effects could be alleviated by three types of interventions. The estimated CHSI indicated that the effective days of the education group were longer than other groups, while the lower CHSI of the subsidy group showed lower sensitivity than the control group. These findings provide feasible implementation strategies to optimize Heat-health action plans and evaluate the intervention performance.  相似文献   
370.
• Fungi enable the constant UASB operation even at OLR of 25.0 kg/(m3×d). • The COD removal of 85.9% and methane production of 5.6 m3/(m3×d) are achieved. • Fungi inhibit VFAs accumulation and favor EPS generation and sludge granulation. • Fungi enrich methanogenic archaea and promote methanogenic pathways. Anaerobic digestion is widely applied in organic wastewater treatment coupled with bioenergy production, and how to stabilize its work at the high organic loading rate (OLR) remains a challenge. Herein, we proposed a new strategy to address this issue via involving the synergetic role of the Aspergillus sydowii 8L-9-F02 immobilized beads (AEBs). A long-term (210-day) continuous-mode operation indicated that the upflow anaerobic sludge bed (UASB) reactor (R1, with AEBs added) could achieve the OLR as high as 25.0 kg/(m3×d), whereas the control reactor (R0, with AEBs free) could only tolerate the maximum OLR of 13.3 kg/(m3×d). Remarkably, much higher COD removal (85.9% vs 23.9%) and methane production (5.4 m3/(m3×d) vs 2.2 m3/(m3×d)) were achieved in R1 than R0 at the OLR of 25.0 kg/(m3×d). Such favorable effect results from the facts that fungi inhibit VFAs accumulation, favor the pH stabilization, promote the generation of more extracellular polymeric substance, and enhance the sludge granulation and settleability. Moreover, fungi may enhance the secretion of acetyl-coenzyme A, a key compound in converting organic matters to CO2. In addition, fungi are favorable to enrich methanogenic archaea even at high OLR, improving the activity of acetate kinase and coenzyme F420 for more efficient methanogenic pathway. This work may shed new light on how to achieve higher OLR and methane production in anaerobic digestion of wastewater.  相似文献   
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