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Mobile monitoring of air and noise pollution in Philadelphia neighborhoods during summer 2017
2019
Shakya, Kabindra M. | Kremer, Peleg | Henderson, Kate | McMahon, Meghan | Peltier, Richard E. | Bromberg, Samantha | Stewart, Justin
Mobile monitoring is an useful approach for measuring intra-urban variation of air pollution in urban environments. In this study, we used a mobile monitoring approach to study the spatial-temporal variability of air and noise pollution in urban neighborhoods of Philadelphia. During summer 2017, we used portable instruments to measure PM2.5, black carbon (BC), and noise levels along 5 km paths in four residential neighborhoods (Tioga, Mill Creek, Chestnut Hill, and Northern Liberties) and one commercial district (Center City) in Philadelphia, Pennsylvania, USA. A total of 62 sets of measurements were made at three different times of day (during morning rush hour, mid-afternoon, and during afternoon rush hour) from June 5 to July 7, 2017. Spatially, there was a significant difference in PM2.5 concentrations among the four residential neighborhoods. Overall, the Chestnut Hill neighborhood had the highest PM2.5 concentrations (13.25 ± 6.89 μg/m3), followed by Tioga (9.58 ± 4.83 μg/m3), Northern Liberties (7.02 ± 4.17 μg/m3), and Mill Creek (3.9 ± 4.5 μg/m3). There was temporal variability of pollutants depending on the neighborhood; Northern Liberties demonstrated the highest temporal variability in these data. The highest PM2.5 (18.86 ± 3.17 μg/m3) was measured in the Chestnut Hill neighborhood during morning rush hour. Mean PM2.5, BC, and noise levels based on mobile measurements at Philadelphia during summer 2017 were 8.41 ± 4.31 μg/m3, 0.99 ± 0.44 μg C/m3, and 62.01 ± 3.20 dBA, respectively. Environmental noise showed the highest temporal variation of the monitored components for 3 time periods. Generally, an increase in tree cover led to a decrease in PM2.5.
Mostrar más [+] Menos [-]Potential for Reducing On-Farm Greenhouse Gas and Ammonia Emissions from Dairy Cows with Prolonged Dietary Tannin Additions
2016
Duval, Benjamin D. | Aguerre, Matias | Wattiaux, Michel | Vadas, Peter A. | Powell, J Mark
Dairy cows are responsible for significant emissions of enteric methane (CH₄) and produce nitrous oxide (N₂O) and ammonia (NH₃) gas from manure. As an abatement strategy, we explored the effects of long-term condensed tannin (Quebracho and chestnut extracts) addition to dairy cow diets. Previous studies have demonstrated that tannins in cow diets reduce methane and ammonia efflux, but none have done so over a >1-month time period. A modified stanchion barn equipped with gas analysis instrumentation measured CH₄, N₂O, and NH₃ fluxes into and from the barn, at the onset of the experiment, and 45 and 90 days after feeding groups of lactating dairy cows a control diet or two levels of tannin extract at 0.45 and 1.8 % of dietary dry matter. Few statistical differences among treatments were observed, likely a consequence of high variability and low sample size necessary for conducting a study of this duration. However, on a per-cow basis, low and high tannin diets lowered CH₄ emissions by 56 g cow⁻¹ day⁻¹ and by 48 g cow day⁻¹, respectively. Diet tannin additions lowered CH₄ (33 %), NH₃ (23 %), and N₂O (70 %) per unit milk corrected emissions in the high tannin treatment compared to the control at the end of the experiment, without significant loss in milk production. These results suggest that relatively low concentrations of diet tannin additions can reduce ruminant CH₄ and gaseous N emissions from manure. The tannin effect observed after 90 days is a starting point for considering tannin additions as a potential long-term strategy for improving the environmental footprint of milk production.
Mostrar más [+] Menos [-]Aerobic Biological Treatment of Chestnut Processing Wastewater
2012
Pirra, António | Lucas, Marco S. | Peres, José A.
Chestnut agro-industrial companies consume a high volume of water for washing and processing fruit, generating a large volume of wastewater. This work studied the biodegradation of chestnut processing wastewater through aerobic assays, varying substrate, and biomass concentrations. In general, this wastewater presents a good biodegradability, especially in experiments with relatively low chemical oxygen demand (COD) (0.4 and 0.6 g O₂ L⁻¹) allowing a COD removal of 85–90 %. The best results were obtained in the reactor initially loaded with 2 g L⁻¹ of biomass and 0.4 or 0.6 g O₂ L⁻¹ of COD. These experiments also showed high COD removal rates: 4.25 and 3.88 g COD g⁻¹ volatile suspended solids (VSS) h⁻¹, respectively. The sedimentation rate, evaluated for different initial values of biomass (1, 2, and 3 g L⁻¹), always presented higher values in the experiments with 2 and 3 g L⁻¹ of biomass, regardless of the initial COD value used. After comparing different kinetic models (Monod, Contois, and Haldane), it was observed that the Haldane inhibition model satisfactorily describes the COD biodegradation. AQUASIM software allowed calculating the kinetic constant ranges: K ₛ, 1.59–6.99 g COD L⁻¹; ν ₘₐₓ, 25–40 g COD g⁻¹ VSS day⁻¹; and K ᵢ values, 0.07–0.11. These kinetic constants corresponds to maximum rates (ν*) between 1.48 and 4.25 g COD g⁻¹ VSS day⁻¹ for substrate concentrations (S*) from 0.38 to 0.88 g COD L⁻¹.
Mostrar más [+] Menos [-]Utilization of water chestnut for reclamation of water environment and control of cyanobacterial blooms
2014
Akao, Satoshi | Hosoi, Yoshihiko | Fujiwara, Taku
Overgrowth of water chestnut (Trapa spp.) is a regional problem throughout Asia and North America because of waterway blockage and water fouling upon decomposition. In the present study, we investigated the potential of water chestnut to control cyanobacterial blooms, via a high content of phenolic compounds. In addition, we assessed the impact of biomass harvesting and crude extract application on nutrient balance. We showed that the floating parts of water chestnut contained high concentrations of total phenolics (89.2 mg g⁻¹dry weight) and exhibited strong antioxidant activity (1.31 mmol g⁻¹dry weight). Methanol-extracted phenolics inhibited growth of Microcystis aeruginosa; the half maximal effective concentration (EC₅₀) of the extracted phenolics was 5.8 mg L⁻¹, which was obtained from only 103 mg L⁻¹of dry biomass (the floating and submerged parts). However, the crude extracts also added important quantities of nitrogen, phosphorus, and potassium (1.49, 1.05, and 16.3 mg g⁻¹, respectively; extracted dry biomass weight basis); therefore, in practice, nutrient removal before and/or after the extraction is essential. On the other hand, biomass harvesting enables recovery of nitrogen, phosphorus, and potassium from the water environment (23.1, 2.9, and 18.7 mg g⁻¹, respectively; dry biomass weight basis). Our findings indicate that water chestnut contains high concentrations of phenolics and exhibits strong antioxidant activity. Utilization of these resources, including nutrients, will contribute to reclamation of the water environment, and also to disposal of wet biomass.
Mostrar más [+] Menos [-]Cascade utilization of water chestnut: recovery of phenolics, phosphorus, and sugars
2013
Akao, Satoshi | Maeda, Koutaro | Hosoi, Yoshihiko | Nagare, Hideaki | Maeda, Morihiro | Fujiwara, Taku
Overgrowth of aquatic plants, such as water chestnut, has been reported as a regional problem in various areas. We proposed cascade utilization of water chestnut through the recovery of phenolics, phosphorus, and sugars. Phenolics were extracted using 50 g (wet weight) of biomass with 300 mL of acetone, methanol, or hot water, and the yields of total phenolics were 80.2, 56.2, and 49.7 mg g(-1) dry weight of native biomass, respectively. The rate of eluted phosphorus in the phenolic extraction step was 8.6, 14.8, and 45.3 % of that in the native biomass, respectively, indicating that the use of polar organic solvents suppressed phosphorus elution at the phenolic extraction step. Extraction of phosphorus following the phenolic extraction was combined with alkaline pretreatment (1 % NaOH solution) of biomass for saccharification; 64.1 and 51.0 % of phosphorus in the native biomass were extracted using acetone and methanol for the phenolic extraction, respectively. Saccharification following the alkaline pretreatment showed that the glucose recovery rates were significantly increased (p < 0.05) with the phenolic extraction step compared to alkaline pretreatment alone. This finding indicates that extraction of phenolics not only provides another useful material but also facilitates enzymatic saccharification.
Mostrar más [+] Menos [-]A new approach for the modelling of chestnut wood photo-degradation monitored by different spectroscopic techniques
2017
Bonifazi, G. | Calienno, L. | Capobianco, G. | Monaco, A Lo | Pelosi, C. | Picchio, R. | Serranti, S.
The aim of this work is to study the colour and chemical modifications of the surfaces in chestnut wood samples as a consequence of irradiating in a controlled environment. The changes were investigated by a new analytical approach by combining traditional techniques such as reflectance spectrophotometry in the visible range and Fourier transform infrared spectroscopy with new hyperspectral imaging, in order to obtain forecast models to describe the phenomenon. The statistical elaboration of the experimental data allowed to validate the measurements and to obtain models enabling to relate the investigated parameters; the elaboration of the hyperspectral images by chemometric methods allowed for studying the changes in the reflectance spectra. A result of great importance is the possibility to correlate the oxidation of wood chemical components with the colour change in a totally non-invasive modality. This result is particularly relevant in the field of cultural heritage and in general in the control processes of wooden materials.
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