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1.
Environmental Science and Pollution Research - A mechanical harvesting technology based on coupling flocculation with a rotary drum filter (RDF, 35-μm) was applied to remove cyanobacterial...  相似文献   
2.
Environment, Development and Sustainability - Due to rapid socioeconomic development, seeking the coordination of resources exploitation and the ecological environment has become an objective...  相似文献   
3.
针对2018年3月9—15日京津冀地区的一次空气重污染过程,进行了基于地基颗粒物激光雷达组网的星载-地基联合观测分析。颗粒物激光雷达观测到污染前期为局地污染累积过程,中期有明显的污染物区域传输过程,北京受太行山沿线城市污染输送影响较大。风廓线激光雷达观测结果表明:此次污染过程近地面主要为偏南风且风力较弱,冷空气到来时风向转为较强东北风,导致污染消散。微波辐射计观测到保定在污染过程中出现持续6 d的逆温层,同时在污染过程中近地面相对湿度较高,逆温层被打破后污染开始消散。在污染过程的各个阶段中,污染团的空间分布与变化特征均被很好地反映出来,可见地天联合观测对污染物的累积与输送研究有较大的意义,能对京津冀及周边地区的大气污染联防联控提供有力支持。  相似文献   
4.
The structural, thermal, mechanical, and biodegradable properties of composite materials made from polylactide (PLA) and agricultural residues (arrowroot (Maranta arundinacea) fibre, AF) were evaluated. Melt blended glycidyl methacrylate-grafted polylactide (PLA-g-GMA) and coupling agent-treated arrowroot fibre (TAF) formed the PLA-g-GMA/TAF composite, which had better properties than the PLA/AF composite. The water resistance of the PLA-g-GMA/TAF composite was greater than that of the PLA/AF composite; the release of PLA in water from the PLA/AF and PLA-g-GMA/TAF composites indicated good biological activity. The PLA-g-GMA/TAF material had better mechanical properties than PLA/AF. This behaviour was attributed to better compatibility between the grafted polymer and TAF. The results indicated that the Tg of PLA was increased by the addition of fibre, which may have improved the heat resistance of PLA. Furthermore, the mass losses following burial in soil compost indicated that both materials were biodegradable, especially at high levels of AF or TAF substitution.  相似文献   
5.
The CO2 absorption capacities of potassium glycinate, potassium sarcosinate (choline, proline), mono-ethanolamine (MEA), and tri-ethanolamine were evaluated to find the optimal absorbent for separating CO2 from gaseous products by a CO2 purification process. The absorption loading, desorption efficiency, cost, and environmental tolerance were assessed to select the optimal absorbent. MEA was found to be the optimum absorbent for separating the CO2 and H2 mixture in gaseous product. The maximum absorption loading rate was 0.77 mol CO2 per mol MEA at temperature of 20°C and absorbent concentration of 2.5 mol/L, whereas desorption efficiency was 90% by heating for 3 h at 130°C. MEA was found to be an optimal absorbent for the purification process of CO2 during gaseous production.  相似文献   
6.
7.
Objectives: The accuracy of self-reported driving exposure has questioned the validity of using self-reported mileage to inform research questions. Studies examining the accuracy of self-reported driving exposure compared to objective measures find low validity, with drivers overestimating and underestimating driving distance. The aims of the current study were to (1) examine the discrepancy between self-reported annual mileage and driving exposure the following year and (2) investigate whether these differences depended on age and annual mileage.

Methods: Two estimates of drivers’ self-reported annual mileage collected during vehicle installation (obtained via prestudy questionnaires) and approximated annual mileage driven (based upon Global Positioning System data) were acquired from 3,323 participants who participated in the Strategic Highway Research Program 2 (SHRP2) Naturalistic Driving Study.

Results: A Wilcoxon signed rank test showed that there was a significant difference between self-reported and annual driving exposure during participation in SHRP 2, with the majority of self-reported responses overestimating annual mileage the following year, irrespective of whether an ordinal or ratio variable was examined. Over 15% of participants provided self-reported responses with over 100% deviation, which were exclusive to participants underestimating annual mileage. Further, deviations in reporting differed between participants who had low, medium, and high exposure, as well as between participants in different age groups.

Conclusions: These findings indicate that although self-reported annual mileage is heavily relied on for research, such estimates of driving distance may be an overestimate of current or future mileage and can influence the validity of prior research that has utilized estimates of driving exposure.  相似文献   

8.
Environmental Science and Pollution Research - China is the most populous country in the world, and the pollution caused by the excessive population should not be underestimated. In recent years,...  相似文献   
9.
Cassava starch waste hydrolysates (CSWHs) with different degrees of polymerisation, i.e., CSWHs-1, CSWHs-2 and CSWHs-3, were prepared through the hydrolysis of cassava starch waste with thermostable a-amylase from Thermococcus sp. HJ21. The prepared CSWHs were then used as a carbon source for curdlan production with Alcaligenes faecalis ATCC 31749. The amount of curdlan produced and the glucosyltransferase activity during curdlan synthesis increased more obviously when CSWHs-2 was used as the carbon source than when glucose was used. Using both carbon sources, the maximum curdlan production was observed at day 5, and the maximum glucosyltransferase activity was observed at day 4. Glucosyltransferase activity decreased thereafter, and biomass continued to increase until the end of the experiment (day 6). Results indicated that the enhanced curdlan production with CSWHs as the carbon source was highly correlated with glucosyltransferase activity.  相似文献   
10.
Environmental Science and Pollution Research - A Correction to this paper has been published: https://doi.org/10.1007/s11356-021-15526-6  相似文献   
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