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561.
氯离子对COD测定影响的探讨 总被引:1,自引:0,他引:1
研究含有高氯离子样品COD的测定,发现其中的白色沉淀为AgCl。实验结果证明,按照标准方法,当取样体积为20 mL时,按0.4 g HgSO4络合2 000 mg/L Cl-的比例投加掩蔽Cl-可以取得理想的效果。 相似文献
562.
为分析突发性灾难重大事件发生后公众对心理服务的认知和需求现状,采用随机抽样的方法在全国范围内抽取458名群众作为被试,使用“突发性灾难重大事件后公众心理服务认知和需求”调查问卷进行调查。结果显示:①不同性别人群、不同年龄阶段人群对“突发性灾难重大事件后心理服务”的认知存在显著差异(X^2=9.82,p<0.05;X^2=33.99,p<0.05)。②不同年龄阶段的人群对民众开展心理服务的必要性态度存在显著差异(X^2=15.84,p<0.05)。不同文化程度人群、不同性别人群对突发性灾难重大事件后心理服务活动的参与意愿存在显著差异(X^2=7.20,p<0.05;X^2=6.78,p<0.05)。③不同文化程度人群对心理服务知识和技能需求存在显著差异(X^2=28.65,p<0.05),在接受心理服务场所的选择上也存在显著差异(X^2=16.44,p<0.05)。不同年龄阶段人群对接受心理服务场所的选择上存在显著差异(X^2=21.52,p<0.05)。分析结果显示:在遭受突发性灾难重大事件时,公众对心理服务的了解程度一般,但参与意愿和需求强烈,因此,国家和社会应加快社会心理服务体系的建设,促进公众的心理健康。 相似文献
563.
Oxidation of sulfurized rust in oil tank is complicated, and it is influenced by numerous factors such as water content, air humidity, operating temperature etc. The paper focuses on the oxidation process of sulfurized rust in the wild. Firstly, samples collected from a petrochemical company were put into the sulfurization & oxidation experimental apparatus to gain wet and dry sulfurized rusts. Their chemical compositions and phase were analyzed by Energy Dispersive X-ray Spectrometer (EDS) -scanning electron microscope (SEM) technique. The results showed that both wet and dry sulfurized rusts had S, Fe2O3, Fe3S4 and FeS2, whereas FeS only existed in wet sulfurized rust. The two kinds of rusts gave a short length of side, diamond appearance and a large pore size in structure. Then oxidation of wet sulfurized rust was investigated, which included electrochemical reaction stage, electrochemical & chemical reaction coexisting stage and chemical reaction stage. The final oxidation product of wet sulfurized was determined to be Fe2O3. On the basis of this study, an indicator for monitoring and early-warning was proposed to prevent plants in vicinity of the accidental vessel or tank from fire and explosion. 相似文献
564.
In order to search the degradability of kraft lignin, the potential bacterial strains Bacillus subtilis (GU193980) and Klebsiella pneumoniae (GU193981) were isolated, screened and applied in axenic and co-culture conditions. Results revealed that mixed culture showed better decolorization efficiency (80%) and reduction of pollution parameters (COD 73% and BOD 62%) than axenic culture. This indicated syntrophic growth of these two bacteria rather than any antagonistic effect. The HPLC analysis of degraded samples of kraft lignin has shown the reduction in peak area compared to control, suggesting that decrease in color intensity might be largely attributed to the degradation of lignin by isolated bacteria. Further, the GC–MS analysis showed that most of the compounds detected in control were diminished after bacterial treatment. Further, the seed germination test using Phaseolus aureus has supported the detoxification of bacterial decolorized kraft lignin for environmental safety. All these observations have revealed that the developed bacterial co-culture was capable for the effective degradation and decolorization of lignin containing rayon grade pulp mill wastewater for environmental safety. 相似文献
565.
566.
某公司硫酸生产线针对生产过程中存在的原材料消耗高、产品转化率低等问题,通过开展清洁生产审核,分析生产过程能耗、物耗、废物产生量的现状,从原辅材料和能源、工艺、设备、过程控制、管理、员工、产品及废物八个方面提出14个清洁生产方案,通过方案的实施,提高了公司清洁生产水平,实现了预防污染、节能降耗减污增效的目的。 相似文献
567.
杨朝飞 《环境与可持续发展》2014,(1):7-8
2013年11月16日能源基金会(美国)主办的"重塑蓝天:空气质量管理国际研讨会"在北京召开,环境保护部原总工程师、中国环境科学学会副理事长杨朝飞受会议主办方委托做了总结讲话。本文根据杨总工的讲话录音整理以飨读者。 相似文献
568.
The paper explores the role of a participatory approach in the outcome of the Finnish sustainable development indicator (SDI) exercise in 1998-2002. The process is analysed through three main objectives: to achieve stronger democracy, better quality of the end product and a more effective process. The analysis is further structured by a set of criteria needed for successful participation and differentiation of types of participants. The criteria comprise three main aspects: fairness, competence and social learning. In addition to the normally mentioned stakeholders (e.g. citizens and interest groups) participants also include experts and civil servants. Using the set of criteria above the participatory approach of the Finnish SDI process is then evaluated, and in the light of this evaluation the paper also discusses the specifications needed as evaluation criteria for national level policy programme processes like developing the SDIs. The results are based on documentation of the indicator task force meetings, written comments and a study of the putative end-users conducted after the publication of the indicators. The results show that the intense and broad participation of experts and civil servants increased the competence of the outcome and led to greater efficiency in working methods. However, this led to technocratic participation, absence of democratic participation and absence of social learning. Thus the ultimate goal of SDIs to contribute to achieving sustainability was not reached. 相似文献
569.
INTRODUCTION: The urban road traffic accident (RTA) risks for the city of Zagreb, Croatia, from 1999 through 2000 were analyzed with the aim of reducing the increasing injury incidence. METHOD: Simple and bivariate analysis using chi(2), odds ratio, and confidence interval of 95% was used to determine risks in three outcome groups: killed, severely, and mildly injured. RESULTS: There were 528 RTA victims consisting of 260 severely, 213 mildly injured, and 55 killed at the scene of an accident and during transportation. More fatal accidents occurred during night hours (OR=3.78; 95% CI, 2.08-6.85), on urban road links (OR=2.33; 95% CI, 1.30-4.19), and at exceeding speed limit (OR=2.56; 95% CI, 1.43-4.61). More people were injured than killed on urban junctions (OR=5.27; 95% CI, 2.21-12.57). The highest combined risk of dying or being severely injured was found in males, driving at excessive speed, on urban links, and during bad visibility (OR=16.15; 95% CI, 3.901-66.881). CONCLUSION: These results will influence the urban traffic police enforcement measures, which will change inappropriate behavior of drivers and protect the least experienced road users. 相似文献
570.
人工湿地氮转化与氧关系研究 总被引:20,自引:6,他引:14
应用N转化迁移模型分析廊道式人工湿地氮转化与氧供应的关系,验证目前湿地全程硝化反硝化脱氮机制的有效性.对各个廊道进出水NH4+-N、NO3--N、TN、B5、DO进行了测定和分析.在水力负荷5cm/d条件下,各廊道湿地有机氮矿化率为0.01~0.28g·(m2·d)-1、氨氮硝化率0.50~1.54 g·(m2·d)-1,反硝化率0.41~1.13 g·(m2·d)-1(占总氮损失的3.4%~35.4%)、植物净吸收氮0.07~0.26 g·(m2·d)-1(占总氮损失的7%~33%).硝化反硝化与有机质降解同时进行,在进水端最明显,这与传统认识相悖.按照全程硝化化学计量学得到的硝化需氧量(NOD)高于实际的表面复氧和植物根系放氧.最后对在高浓度有机质存在条件下,能减少对氧需求的2种新型脱氮机制进行了讨论. 相似文献