废旧硅橡胶酸性热解残渣热解馏出物组分分析

在不同温度下对废旧硅橡胶酸性热解残渣进行热解,通过气相色谱-质谱联用技术对馏出油的组分进行分离与鉴定.实验结果表明:当热解温度为180℃时,馏出油组分相对较单一,主要是低沸点硅油类物质,可再次回收利用,实现清洁生产;当热解温度为340℃时,馏出油组分多且复杂,主要为高沸点硅油类物质,还有硅油类物质氧化和高温热解后的产物...     

The influence of neighborhood traffic density on the respiratory health of elementary schoolchildren

Background

Several studies have found that living near major roadways is associated with an increase in respiratory illness but few studies have measured the volume and type of traffic.

Objective

We investigated the relation between traffic volume and respiratory health of 2328 children 9 to 11 years old in the city of Windsor, Canada.

Methods

We identified the roadways within a 200 meter radius of the child's neighborhood using the latitude and longitude of the residential postal code. Traffic exposure was defined as the sum of the annual volume of vehicles on all of these roadways. Volume was calculated using sensors to detect passing vehicles (simple traffic counts), and by counts and direction of traffic at intersections (turning movement counts). Ventilatory lung function was measured by spirometry and airway inflammation by exhaled nitric oxide (eNO).

Results

The odds ratio between an interquartile increase in truck turning movement counts and chest congestion was 1.20 (1.06-1.35). The percentage of predicted FVC declined 0.68%, (95% CI 1.32, 0.03) for an interquartile increase in simple traffic counts (33,787 vehicles daily). Among those with self-reported asthma, effect sizes were larger. Percentage predicted FEV₁ declined 1.84% (95% CI 0.07, 3.61) associated with an interquartile range increase in turning movement counts. No statistically significant change was detected between traffic measures and exhaled nitric oxide.

Conclusions

Our findings provide further support for the hypothesis that neighborhood exposure to traffic-related air pollution increases respiratory symptoms and reduces ventilatory function in children, especially those with self-reported asthma.     

Short-term impact of olive mill wastewater (OMWW) applications on the physico-chemical and microbiological soil properties of an olive grove in Argentina

The purpose of this work was to investigate the effects of spreading olive oil mill wastewater (OMWW) on soil biochemical parameters and olive production in an organically managed olive orchard. The experiment was carried out with three different doses of OMWW (80, 160 and 500 m³ ha^?1) and a control (untreated soil). Three samplings were done at 10, 30 and 90 days after the administration of the byproduct. OMWW application differentially modified the biochemical properties of the soil analyzed. Organic matter, organic carbon, total nitrogen and extractable phosphorus soil contents increased proportionally with each increasing dose. The values of these parameters decreased gradually with time. Total microbial activity was altered and the OMWW 500 m³ ha^?1 treatment proved to be the most active when compared with the other applied doses. OMWW agricultural application also modified the structure of soil microbial communities, particularly affecting Gram positive and negative bacteria, while fungal biomass did not show consistent changes. Although there was a salinity increase in the treated soil, especially at the highest dose, the productive parameters analyzed (fruit and oil tree^?1) were not affected. In light of the obtained results, we consider that low dose of OMWW could be considered an alternative farming practice for semiarid regions.     

Uncertainty estimation in the analysis of pesticide residues in olive oil using data from proficiency tests

In this work we report the results for estimating the measurement uncertainty (MU) following up the application of two different approaches, relatively the top-down procedure, by using proficiency test data. We have focused the estimation on the olive oil matrix. We used the analytical data obtained from five selected editions of the Proficiency Tests (PTs, from 2007 to 2011) on pesticide residues in olive oil to estimate the MU. These PTs have been organized by Istituto Superiore di Sanità annually in cooperation with International Olive Council (IOC) since 1997. The number of participants in each trial ranged from 10 to 43. We used a total of 34 pesticide results. The expanded uncertainty U _(c) was calculated using a covering factor k = 2 for a confidence interval of 95%. In the approach 1, the within–laboratory reproducibility standard deviation is combined with estimates of the method and laboratory bias using PTs data. In the approach 2, the way of estimating the MU is based only on the bias that the laboratory has obtained participating in a sufficient number of the IOC proficiency tests. Comparing the relative expanded uncertainty based on these different approaches we notice values quite constant and close, from 42% to 48%. Moreover, these calculated expanded uncertainties are less than the default value of 50% (corresponding to a 95% confidence level), adopted from European guidance document SANCO based on the fit-for-purpose relative standard deviation (FFP-RSD).     

Bioconversion of wastes from olive oil industries by vermicomposting process using the epigeic earthworm Eisenia andrei

The present work evaluates the possible bioconversion of wet olive cake by low-cost biostabilization (vermicomposting process). Wet olive cake fresh (WOC), precomposted (WOCP), or mixed with biosolids (WOCB), were vermicomposted for 6 months to obtain organic amendments for agricultural and remediation purposes. The results showed initial differences depending on previous treatment. WOCP was initially more stable, presented a low C:N ratio, and showed more dehydrogenase and urease activity. By contrast, there was no dehydrogenase activity initially in WOC and WOCB, due to the presence of some different types of polyphenols. Finally, the end product showed relatively higher amounts of total nitrogen and humic acid and met the standard of quality for composts and vermicomposts for use both in conventional and organic agriculture and soil-restoration programs.     

响应面法优化克浅十油田废水的混凝沉淀工艺

以克浅十污水处理站原水为研究对象,采用混凝沉淀工艺,探讨优选出的复配混凝剂投加量、助凝剂投加量及静置时间对原水中浊度和总铁去除效果的影响.应用Box-Behnken中心组合实验和响应面分析法,建立混凝剂对处理原水的二次多项式数学模型,确定了混凝沉淀去除原水浊度和总铁的优化工艺参数分别为:复配混凝剂投加量为152.15 mg/L、143.84 mg/L,助凝剂投加量为4.14 mg/L、4.32 mg/L,静置时间为11.77 min、11.22 min.在此工艺条件下回归方程得到的浊度和总铁的去除率预测值与实验值接近,且拟合性良好,误差介于3％～5％之间.通过均值内插法,对比浊度和总铁的多元二次回归方程,推导得出的2组最佳工艺条件均能满足浊度和总铁的去除要求.     

印刷用铝基材碱洗废液的循环利用

对印刷用铝基材碱洗废液进行了循环利用研究。首先将高COD含量的碱洗废液进行除油脱色处理,通过石灰和硬脂酸的协同效应,使COD含量从26300mg／L降至480mg／L,色度降至60°;然后利用含铝碱性废液通过碳化法制备出结晶度66％的拟薄水铝石产品;最后对分离后的碱性废水按配方要求配制,对铝基材进行除油实验,经5次循环表明,除油效果和对铝基材的腐蚀率均100％达标。     

Anti-oxidative property of crude rice oil extracted from cadmium-contaminated rice

Local residents who habitually consume cadmium-contaminated rice (Oryza sativa L.) can be exposed to cadmium toxicity in Mae Sot District, Tak Province, Thailand. This study aimed to investigate an alternative for utilizing cadmium-contaminated rice without compromising their health with hazard risks. First, cadmium (Cd) concentration in rice grain and crude rice oil was determined (0.203 ± 0.030 and 0.007 ± 0.002 mgCd/kg dry weight, respectively). Then crude rice oil extracted from cadmium-contaminated rice grain was studied for its anti-oxidative property using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging approach. Next, quantitative analysis of γ-oryzanol in crude rice oil was conducted. Results indicated that the level of cadmium concentration in the rice grain could cause adverse effects on human health. However, the amount of cadmium in the crude rice oil was safe for consumption. In crude rice oil anti-oxidative property, crude rice oil extracted from cadmium-contaminated rice was significantly higher than the control (P < 0.05). The concentration of γ-oryzanol in crude rice oil extracted from cadmium-contaminated rice was significantly higher than that in the control crude rice oil (P < 0.05). This study demonstrates an alternative way to use the rice grown in cadmium-contaminated areas for crude rice oil production for its anti-oxidative properties.     

罐底含油污泥萃取溶剂的选择与优化

针对某炼化企业在石油储运过程中产生的罐底油泥,进行了油泥样分析和不同萃取剂萃取回收油分实验.经分析该罐底油泥含水率约16.1％,总有机物含量约34.8％,其中可萃取石油类物质约占总有机物成分的67.0％.考察不同溶剂的萃取效果,结果表明,石脑油90 ～ 110℃沸程段的馏分油的萃取效果和工艺可操作性优越于其他常用溶剂,其萃取效果排序为石脑油90～ 110℃沸程段的馏分油＞120#溶剂油＞正庚烷＞石油醚(90 ～ 120℃)＞石油醚(60 ～ 90℃);用石脑油90 ～ 110℃沸程段的馏分油在优化萃取工艺条件下,经两次萃取可分离出大于96％的可萃取油分,罐底油泥中有机物的萃出率可达64％以上,比120#溶剂油萃取效果高出约3％～5％,实现了罐底油泥更深程度的萃取和资源化利用.     

基于GA-BP算法的含油污泥处理 工艺参数优化

在含油污泥进行资源化处理过程中,针对处理目标受多个因素影响的实际,为了解决工艺之间的耦合问题,采用正交实验的方法来解决,并把主要参数作为优化对象,把含油污泥的脱水率作为评价目标,通过采用GA-BP算法对含油污泥耦合工艺正交实验参数进行了线性与非线性分析.在采用遗传算法优化神经网络的权值和阈值的基础上,用优化后的权值和阈值对测试样本和训练样本进行了预测.预测结果表明,预测误差都有明显减小,分别由0.34211减少到0.031549和0.15476减少到0.040682,可见耦合参数趋向于非线性优化.