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71.
In this study, the adsorption of bisphenol A (BPA) and 17α-ethinyl estradiol (EE2) from landfill leachate onto single-walled carbon nanotubes (SWCNTs) was investigated. Different leachate solutions were prepared by altering the pH, ionic strength, and dissolved organic carbon (DOC) in the solutions to mimic the varying water conditions that occur in leachate during the various stages of waste decomposition. The youngest and oldest leachate solutions contained varying DOC and background chemistry and were represented by leachate Type A (pH = 5.0; DOC = 2500 mg/L; conductivity = 12,500 μS/cm; [Ca2+] = 1200 mg/L; [Mg2+] = 470 mg/L) and Type E (pH = 7.5; DOC = 250 mg/L; conductivity = 3250 μS/cm; [Ca2+] = 60 mg/L; [Mg2+] = 180 mg/L). These solutions were subsequently combined in different ratios to produce intermediate solutions, labeled B-D, to replicate time-dependent changes in leachate composition. Overall, a larger fraction of EE2 was removed as compared to BPA, consistent with its higher log KOW value. The total removal of BPA and EE2 decreased in older leachate solutions, with the adsorptive capacity of SWCNTs decreasing in the order of leachate Type A > Type B > Type C > Type D > Type E. An increase in the pH from 3.5 to 11 decreased the adsorption of BPA by 22% in young leachate and by 10% in old leachate. The changes in pH did not affect the adsorption of EE2 in the young leachate, but did reduce adsorption by 32% in the old leachate. Adjusting the ionic strength using Na+ did not significantly impact adsorption, while increasing the concentration of Ca2+ resulted in a 12% increase in the adsorption of BPA and a 19% increase in the adsorption of EE2. DOC was revealed to be the most influential parameter in this study. In the presence of hydrophilic DOC, represented by glucose in this study, adsorption of the endocrine disrupting compounds (EDCs) onto the SWCNTs was not affected. In the absence of SWCNTs, hydrophobic DOC (i.e., humic acid) adsorbed 15-20% of BPA and EE2. However, when the humic acid and SWCNTs were both present, the overall adsorptive capacity of the SWCNTs was reduced. Hydrophobic (π-π electron donor-acceptor) interactions between the EDCs and the constituents in the leachate, as well as interactions between the SWCNTs and the EDCs, are proposed as potential adsorption mechanisms for BPA and EE2 onto SWCNTs. 相似文献
72.
Vladimir Totolin Ichiro Minami Christoph Gabler Joseph Brenner Nicole Dörr 《Tribology Letters》2014,53(2):421-432
The assessment of ionic liquids (ILs) as lubricants in several tribological systems has shown their ability to provide remarkable reduced friction and protection against wear, whether they are used as additives or in the neat form. However, their corrosion and limited solubility in non-polar hydrocarbon oils represent the bottleneck-limiting factors for the use of ILs as lubricants. Therefore, in order to tackle these problems, mixtures of alkylborane–imidazole complexes with one halogen-free IL as additive were used in this study. The knowledge of the additive–surface interactions and hence the understanding of tribological properties are an important issue for lubricant formulations and were also investigated in this work. Thus, combination effects between two ionic liquid additives, a halogenated and a halogen-free one, were evaluated by a ball-on-disc-type tribometer under boundary lubrication conditions. Effective friction reduction and anti-wear properties have been demonstrated in tribological investigations when adding between 0.7 and 3.4 wt% of the halogen-free IL into base fluid composed of alkylborane–imidazole complexes. X-ray photoelectron spectroscopy analyses of the steel specimens were conducted to study the correlation between tribological properties and chemical surface composition of the boundary films formed on the rubbing surface. This work suggests potential applications for using halogen-free ILs as additives for synthetic ionic liquid lubricants. 相似文献
73.
74.
Bradizza Clara M.; Maisto Stephen A.; Vincent Paula C.; Stasiewicz Paul R.; Connors Gerard J.; Mercer Nicole D. 《Canadian Metallurgical Quarterly》2009,77(6):1147
Few investigators studying alcohol abuse among individuals with a severe mental illness (SMI) have examined predictors of posttreatment alcohol outcomes. In the present study, a multivariate approach based on a theoretical model was used to study the relationship between psychosocial factors and post-treatment-initiation alcohol use. Predictors of alcohol use outcomes were examined in 278 individuals diagnosed with a current schizophrenia-spectrum or bipolar disorder and an alcohol use disorder (AUD). At 6-months follow-up, 144 of 228 available participants (63%) had good clinical outcomes. The results of structural equation modeling indicated that type of pretreatment residential setting was directly related to treatment, with participants who lived in supervised settings (41%) reporting significantly more days of treatment (β = .34, p 相似文献
75.
Haris Doukas Alexandra G. Papadopoulou Christos Nychtis John Psarras Nicole van Beeck 《Renewable & Sustainable Energy Reviews》2009,13(3):682-688
The European Union (EU) from the beginning of 2007 has focused its emphasis on the development of a new policy that puts energy back at the heart of EU action. Indeed, it has very often been stated that the difficulty and complexity of achieving green energy targets in the EU will require strengthened measures to promote implementation of new energy technologies (NET), as well as measures to support the related energy Research and Technology Development (R&TD). Often forgotten is the fact, that most of all, a European-wide co-ordinated forum is needed to continuously develop and sophisticate the monitoring and methodology results, bringing together specialised statisticians, energy researchers and experts on energy socio-economics. Today a nebulous picture prevails on the existence of categorized data with regards to energy Research and Technology Development (R&TD) expenditure. In this context, aim of this paper is the presentation of energy R&TD data collection strategies, as well as the related findings for the Greek energy market. 相似文献
76.
Lochman John E.; Boxmeyer Caroline; Powell Nicole; Qu Lixin; Wells Karen; Windle Michael 《Canadian Metallurgical Quarterly》2009,77(3):397
This study examined an important but rarely investigated aspect of the dissemination process: the intensity of training provided to practitioners. Counselors in 57 schools were randomly assigned to 1 of 3 conditions: Coping Power–training plus feedback (CP-TF), Coping Power–basic training (CP-BT), or a comparison condition. CP-TF counselors produced reductions in children’s externalizing behavior problems and improvements in children’s social and academic skills in comparison to results for target children in both the comparison and the CP-BT conditions. Training intensity was critical for successful dissemination, although the implementation mechanism underlying this effect remains unclear, as condition effects were not significant for completion of session objectives but were significant for the quality of counselors’ engagement with children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Giao Nguyen Daniel Nicole Marek Matlengiewicz Denis Roizard Norbert Henzel 《Polymer International》2001,50(7):784-791
The glass transition temperature of a series of samples of the poly[(methyl methacrylate)‐co‐(ethyl acrylate)] copolymer, synthesized at low conversion, were calculated theoretically using the equations of Barton and Johnston. The values obtained are more precise when the probabilities of the compositional diads are derived from the 13C NMR data instead of the classical method utilizing reactivity ratios. This can be observed more clearly when the copolymer samples are synthesized at high conversion. Introduction of configuration (tacticity) at the diad level confirms the above observations and slightly improves the calculated values of Tg compared to the initial formulae which were only taking into account the compositional sequences of the copolymer. © 2001 Society of Chemical Industry 相似文献
78.
Nicole Wrage Frank Küchenmeister Johannes Isselstein 《Nutrient Cycling in Agroecosystems》2011,90(2):189-199
Stable isotope signatures of cattle tail switch hair or meadow vegetation have been found to be related to nitrogen (N) surpluses
of whole farms and of meadows, respectively. Permanent pastures are more patchy in terms of nutrient inputs and outputs and
N balances for the whole plot do not necessarily give correct impressions of losses. We here investigated correlations between
isotopic signatures and N balances calculated for different spatial and temporal scales in permanent pastures. N concentrations
and δ15N values of cattle tail switch hair, vegetation and soil samples were measured in an experiment with different grazing intensities
started in 2002. Results were compared to soil surface balances calculated for the whole plot or for plot areas affected by
either dung, urine, grazing without excreta input, or the pasture area without dung pats. There were no significant correlations
between plant or cattle hair isotopic signatures and any of the balances. N fixation probably influenced vegetation signatures,
making the isotopic values less dependent on soil and more on atmospheric N. The cattle preferred short mixed vegetation with
more legume biomass, which also influenced the 15N values of their hair. The 15N signatures of soil samples were the best indicators of partial N balances in these heterogeneous pastures, probably because
soil values are most directly influenced by N inputs and outputs. Still, soil signatures only explained between 15 and 35%
of the variation in balance results. Thus, none of the tested parameters can be used as a reliable indicator of N balance
results in this heterogeneous system with small differences in budgets among treatments and potentially small plot-scale N
losses. 相似文献
79.
80.