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结合工程实例介绍了双冲击泡沫水浴除尘器的应用领域、结构特点、处理效果及其现实意义和发展前景。 相似文献
43.
三峡库区长江水位变化条件下滑坡稳定性二元指标体系研究 总被引:1,自引:0,他引:1
安全系数是边坡稳定性评价中的常用方法,在长期的工程实践中积累了丰富的经验,其最大的缺点是不能考虑边坡岩土体中实际存在的不确定性。可靠性理论可有效地考虑边坡系统内实际存在的不确定性和相关性,但是缺乏丰富的工程实践经验,因此,将工程实践经验丰富的安全系数与先进的可靠性理论相结合,建立安全系数与可靠性相耦合的二元评价体系具有重要的理论意义和应用价值。以巴东县东壤口镇宋家屋场滑坡为实例,计算了长江水位从135 m至175 m变化过程中的平均安全系数(最大可能安全系数)和相应的可靠性。将最大可能安全系数与边坡可靠性相乘,对最大可能安全系数进行折减,得到边坡可靠的安全系数。设折减后安全系数的临界值为1.05,由此计算出不同最大可能安全系数的临界变异系数和临界破坏概率。根据不同的最大可能安全系数及它的临界破坏概率,绘制出边坡稳定性分区图。用均值安全系数和可靠性二元指标对宋家屋场滑坡的稳定性进行了评价,结果是可靠的安全系数为1.068,略大于临界值,处于基本稳定状态。文中论述了边坡稳定性二元指标体系的建立方法。 相似文献
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混燃甲醇和乙醇改善柴油机碳烟排放 总被引:13,自引:0,他引:13
以柴油机为基础,以乙醇或甲醇作为预混合燃料,与喷入的柴油组成部分预混的复合燃烧,大幅度降低了发动机排气烟度,同时使氮氧化物排放得到一定改善,发动机的燃油消耗率优于原柴油机,而HC排放,尤其是在低负荷时有所增加,甲醇比乙醇具有降低烟度效果更好、氮氧化物降低更多和HC及CO排入增加较少的优越性。 相似文献
46.
Oxidation inhibition of sulfite in dual alkali FGD system 总被引:1,自引:0,他引:1
MO Jian-song WU Zhong-biao CHENG Chang-jie GUAN Bao-hong ZHAO Wei-rong 《环境科学学报(英文版)》2007,19(2):226-231
A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization (FGD) system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation. In the absence of catalyst, sodium thiosulfate at 12.67 mmol/L had an inhibition efficiency of approximately 98%. While in the presence of catalyst, sodium thiosulfate at 26.72 mmol/L had an inhibition efficiency less than 85.0%. The oxidation reaction order of sulfite in the sodium thiosulfate was determined to be -1.90 and 4).55 in the absence and presence of the catalyst, respectively. Apparent activation energy of oxidation inhibition was calculated to be 53.9 kJ/mol. Pilot tests showed that the consumption rate of thiosulfate agreed well with the laboratory-scale experimental results. 相似文献
47.
拟面积多波长数据线性双组合解析萘,1—萘酚和2—萘酚同步荧光光谱的研究 总被引:2,自引:0,他引:2
本文研究了Δλ(λem-λex)为130nm和PH12.0条件下,萘、1-萘粉和2-萘酚混合物的同步荧光光谱,获三者同步荧光峰信息,且萘被完全分辨,另外,提出用拟面积多波长线性双组合计算解析重叠的1-萘酚和2-萘酚同步荧光光谱,解析结果的精密度、组份间浓度比范围均较多波长线性回归、双峰增配平和一阶导数解析混合物同步荧光光谱结果为优。 相似文献
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Robert Leconte Rangesan Narayanan Trevor C. Hughes 《Journal of the American Water Resources Association》1988,24(2):247-253
ABSTRACT: A general methodology to study the economics of dual water systems (defined here as a separate distribution system for untreated low quality local surface Water for outdoor municipal water supply) is summarized and the application of the method to a rapidly growing city is presented. In the first step, a cost-benefit criterion for evaluating dual systems is developed. The criterion is then extended to a dynamic case where the population to be served increases with time and where the dual system is allowed to expand. The optimal investment time to introduce the dual water supply project is obtained by maximizing social welfare. The model is applied to the city of West Jordan, Utah, where a dual system is currently being proposed. Model results indicate that for the city as a whole dual supply is not economically feasible. However, when the model is applied to a part of the city, it is found feasible and the optimal time to initiate the project would be in the year 1989. 相似文献
49.
The rise of dual‐earner couples challenges traditional gender stereotypes of women as “caregivers” and men as “breadwinners” and significantly impacts the ways in which partners define their roles as family members. The way in which individuals construe their family identities has implications not only for the decisions they make at home but also decisions in the workplace. In this paper, we propose an updated understanding of the different ways in which men and women can construe their family identity—specifically, in terms of care and/or career. Based upon this nuanced understanding of family identity, we outline five dual‐earner couple types—traditional, non‐traditional, family first, outsourced, and egalitarian—that stem from distinct combinations of partners' family identities. We also outline an agenda for theory and research that challenges scholars to further explore our proposed construals of family identity, work–family decisions at the couple level of analysis, and the interplay between family identity and social context. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
50.
分别采用十八烷基三甲基氯化铵(OATC)和磷酸改性电极并负载铁涂覆在碳布表面,制得Fe/OC-OATC电极和Fe/PC电极用于构建生物电芬顿系统,提高电芬顿技术中H2O2的原位生产能力,达到高效降解印染废水的目的.通过极化曲线、功率密度曲线以及循环伏安曲线对2种复合电极的电化学性质进行分析,结果表明,Fe/OC-OATC的电流密度、最大功率密度以及氧还原能力等均优于Fe/PC,最大功率密度为4.89W/m3,相应的电流密度可达22.9A/m3.然后探究了2种复合电极构建的生物电芬顿系统对罗丹明B的降解效果,结果显示,Fe/OC-OATC体系﹥ Fe/PC体系,Fe/OC-OATC体系对罗丹明B的去除率最高达96.4%.最后根据动力学分析和反应机理的研究,分析了2种系统对罗丹明B的降解机理. 相似文献