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81.
水中氨氮含量是反应水质状况的重要指标。文章对测定水中氨氮气相分子吸收光谱法(标准号HJ/T195-2005)进行了改进试验研究。第一,对氧化剂的配比进行了改进,使氨氮的测定范围扩展至100μg。第二,对标准HJ/T195-2005中直接使用亚硝酸钠标准溶液做标准曲线的处理方式也做了探讨。通过一系列对比实验认为,应用硫酸铵标准溶液做工作曲线更加准确合理。最后应用改进后的气相分子吸收光谱法和纳氏比色法或滴定法对多种实际废水样品进行同时测定。结果表明,改进后的气相分子吸收光谱法测定氨氮的范围更宽,灵敏度更高和准确度更好。  相似文献   
82.
83.
胡国强 《化工环保》1996,16(6):369-372
以由地洛试剂为氧化剂,用分光光度法测定染料废水中对氨基酚的含量,进行了波长,贝特洛试剂用量及显色时间等分析条件的选择。精密度和准确度实验结果表明,该准确,快速,可用于染料废水中对氨基酚的测定。  相似文献   
84.
85.
O/W型乳化液的处理   总被引:2,自引:0,他引:2  
采用药剂破乳-电解破乳工艺处理O/W型乳化液,药剂破乳选用聚合硫酸铁为破乳剂,破乳时最佳PH为8,聚合硫酸铁的最佳投量为1500mg/L,电解破乳选用铁作阳极,铝作阴极,电流密度0.86A/dm^2,极距25mm,电解时间3h。在上述条件下,破乳效果良好,出水清澈透明,COD总去除率可达到96-97%。  相似文献   
86.
Corn distillers’ dry grain, corncob powder, hardwood powder, and sugar beet pulp were separately anionized by oxidation with sodium hypochlorite in aqueous solution. Solid reaction products instantly precipitated upon admixing each of the above-oxidized materials with soy protein isolate. Infrared spectra and differential scanning calorimetry supported the hypothesis that soy protein isolate complexed with all of the above-oxidized polysaccharides. Reaction products with either oxidized corn distillers’ dry grain or oxidized sugar beet pulp provided hard, brittle pellets with tensile strengths as high as 9.5 MPa, suggesting that these materials could be viable as biodegradable plastics.  相似文献   
87.
New data on the vapour pressures and aqueous solubility of 1,8-dichlorooctane and 1,8-dibromooctane are reported as a function of temperature between 20&nbsp;°C and 80&nbsp;°C and 1&nbsp;°C and 40&nbsp;°C, respectively. For the vapour pressures, a static method was used during the measurements which have an estimated uncertainty between 3% and 5%. The aqueous solubilities were determined using a dynamic saturation column method and the values are accurate to within ±10%. 1,8-Dichlorooctane is more volatile than 1,8-dibromooctane in the temperature range covered (p<sub>satsub> varies from 3 to 250&nbsp;Pa and from 0.53 to 62&nbsp;Pa, respectively) and is also approximately three times more soluble in water (mole fraction solubilities at 25&nbsp;°C of 5.95&nbsp;×&nbsp;10<sup>−7sup> and 1.92&nbsp;×&nbsp;10<sup>−7sup>, respectively). A combination of the two sets of data allowed the calculation of the Henry’s law constants and the air water partition coefficients. A simple group contribution concept was used to rationalize the data obtained.  相似文献   
88.
Well-written procedures are an integral part of any industrial organization for safe operation, managing risks, and continuous improvement. Regulatory bodies around the world require industries to have current, accurate, and appropriate procedures for most processes. Although the importance of procedures is recognized by all industries in general, significant incidents still occur due to procedural breakdowns. Some of the procedural breakdowns come from obvious problems such as the procedure not being available or the procedure being wrong. However, some incidents have occurred when correct procedures were available and the operator used those procedures. In these instances, the reason workers do not follow procedures correctly may be attributable the procedure being presented or designed in a manner that does not sufficiently communicate the information in a manner that is easily and quickly understood. This indicates that procedure writers may need more guidance on how to write and design procedures so they accomplish this. To effectively manage risk, procedures need to be technically correct (and regulatory compliant) and usable. As part of this, the current work is focused on developing a systematic approach to a procedure writer's guide that includes a regulatory compliant component. The work presented here consists of an effort to identify procedure-writing practices necessary to ensure regulatory compliance by summarizing a large sample of regulations and standards from several industries. The regulations and standards were organized to reflect common ideas and the implications in terms of human factors needs for procedure design were identified. This information will be used as part of the development of a writer's guide that accounts for human factors (HF) that includes explanations of HF implications and empirical support for each of the guidelines. The novelty of the method and information presented here is in the idea of leveraging the cumulative information available regarding procedures in regulations and standards. Incorporating this information into a procedure's writers guide in this manner may not only facilitate procedure being regulatory compliant for facilities in different geographies of the world, but could also support their being written with considerations for human performance.  相似文献   
89.
首先分析了我国《安全生产法》的发展沿革,且认真学习了目前发布的《安全生产法》征求意见稿,归纳了征求意见稿还应实现四个重点突破:必须体现以人为本的执政理念;职业危害防治应列为《安全生产法》的重要条款之一;安全生产执法监察应与公共安全及行政管理分离;应对工伤保险预防机制作出明确要求。此外,建议通过《安全生产法》的进一步修订实现我国安全生产的制度化建设:建议逐步建立安全生产分级监察管理体制;推进风险管理制度,对企业实行风险分级与分级监管;逐步提出建立安全生产监察员专业化制度;建立与国际接轨的生产安全事故统计报告系统;强化城市建设土地使用规划的风险管理和安全许可;生产安全事故应急管理应强化应急准备工作;建立独立生产安全事故调查机构和公开公正调查程序;应在《安全生产法》中明确"安全生产委员会"的组织形式和功能;生产安全事故责任追究应与激励政策相结合。  相似文献   
90.
Nowadays, more people tend to spend their recreational time in large national parks, and trace metal(loid)s in soils have attracted long-term attention due to their possible harm to human health. To investigate the pollution levels, potential sources and health risks of trace metal(loid)s in road soils, a total of eight trace metal(loid)s (including As, Cd, Cr, Cu, Ni, Pb, Zn and Hg) from 47 soil samples along roads were studied in the Huangshan National Park in Southeast China. The results showed that the concentrations of As, Cd, Pb, Zn and Hg appeared different degrees of pollution compared with their corresponding background values. According to the pollution indices, Hg and Cd were recognized as significant pollutants presenting moderate to high ecological risk. Combining principal component analysis and positive matrix factorization model, the results showed that traffic, industrial, agricultural and natural sources were the potential origins of trace metal(loid)s in this area, with contribution rates of 39.93%, 25.92%, 10.53% and 23.62%, respectively. Non-carcinogenic risks were all negligible, while the carcinogenic risk of As was higher than the limit (1 <span class="math">s="true">×span> 10<sup>−6sup>). Moreover, children were more susceptible to trace metal(loid)s by ingestion which appeared to be a more important exposure pathway than dermal contact and inhalation. The contribution rates of different sources to non-carcinogenic risks and carcinogenic risks were similar among children and adults, while traffic and industrial sources have a significant impact on health risks. This study will give more insights to control the environmental risks of trace metal(loid)s in national parks.  相似文献   
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