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Synthesis, characterization, and application of 1-butyl-3-methylimidazolium thiocyanate for extractive desulfurization of liquid fuel Full text
2016
1-Butyl-3-methylimidazolium thiocyanate [BMIM]SCN has been presented on extractive desulfurization of liquid fuel. The FTIR, ¹H-NMR, and C-NMR have been discussed for the molecular confirmation of synthesized [BMIM]SCN. Further, thermal, conductivity, moisture content, viscosity, and solubility analyses of [BMIM]SCN were carried out. The effects of time, temperature, sulfur compounds, ultrasonication, and recycling of [BMIM]SCN on removal of dibenzothiophene from liquid fuel were also investigated. In extractive desulfurization, removal of dibenzothiophene in n-dodecane was 86.5 % for mass ratio of 1:1 in 30 min at 30 °C under the mild process conditions. [BMIM]SCN could be reused five times without a significant decrease in activity. Also, in the desulfurization of real fuels, multistage extraction was examined. The data and results provided in the present paper explore the significant insights of imidazolium-based ionic liquids as novel extractant for extractive desulfurization of liquid fuels.
Show more [+] Less [-]Earthworms, pesticides and sustainable agriculture: a review Full text
2016
The aim of this review is to generate awareness and understand the importance of earthworms in sustainable agriculture and effect of pesticides on their action. The natural resources are finite and highly prone to degradation by the misuse of land and mismanagement of soil. The world is in utter need of a healthy ecosystem that provides with fertile soil, clean water, food and other natural resources. Anthropogenic activities have led to an increased contamination of land. The intensification of industrial and agricultural practices chiefly the utilization of pesticides has in almost every way made our natural resources concave. Earthworms help in a number of tasks that support many ecosystem services that favor agrosystem sustainability but are degraded by exhaustive practices such as the use of pesticides. The present review assesses the response of earthworm toward the pesticides and also evaluates the relationship between earthworm activity and plant growth. We strictly need to refresh and rethink on the policies and norms devised by us on sustainable ecology. In an equivalent way, the natural resources should be utilized and further, essential ways for betterment of present and future livelihood should be sought.
Show more [+] Less [-]No tillage combined with crop rotation improves soil microbial community composition and metabolic activity Full text
2016
Sun, Bingjie | Jia, Shuxia | Zhang, Shixiu | McLaughlin, Neil B. | Liang, Aizhen | Chen, Xuewen | Liu, Siyi | Zhang, Xiaoping
Soil microbial community can vary with different agricultural managements, which in turn can affect soil quality. The objective of this work was to evaluate the effects of long-term tillage practice (no tillage (NT) and conventional tillage (CT)) and crop rotation (maize-soybean (MS) rotation and monoculture maize (MM)) on soil microbial community composition and metabolic capacity in different soil layers. Long-term NT increased the soil organic carbon (SOC) and total nitrogen (TN) mainly at the 0–5 cm depth which was accompanied with a greater microbial abundance. The greater fungi-to-bacteria (F/B) ratio was found in NTMS at the 0–5 cm depth. Both tillage and crop rotation had a significant effect on the metabolic activity, with the greatest average well color development (AWCD) value in NTMS soil at all three soil depths. Redundancy analysis (RDA) showed that the shift in microbial community composition was accompanied with the changes in capacity of utilizing different carbon substrates. Therefore, no tillage combined with crop rotation could improve soil biological quality and make agricultural systems more sustainable.
Show more [+] Less [-]Air quality improvement during 2010 Asian games on blood coagulability in COPD patients Full text
2016
Zhang, Zili | Wang, Jian | Guo, Meihua | Xiong, Mingmei | Zhou, Qipeng | Li, Defu | Shu, Jiaze | Lu, Wenju | Sun, Dejun
Exposure to elevated levels of ambient air pollutants can lead to adverse cardiovascular effects. Perturbation of the coagulation balance is one of the potential mechanisms. However, evidence regarding the impact of improvement in air pollution on blood coagulability in COPD patients has never been reported. Coagulation processes are known to be of relevance for cardiovascular pathology; therefore, this study aimed to investigate the association of short-term air pollution exposure with blood marker (D-dimer) of coagulation. A 3-year (through the Asian game) cohort study based on the GIRD COPD Biobank Project was conducted in 36 COPD patients to estimate whether changes in measurements of D-dimer were associated with changes in pollutant concentration, comparing for 51 intervention days (November 1–December 21) in 2010 with the same calendar date of baseline years (2009 and 2011). Daily mean concentrations of air pollutants and meteorological variables were measured during the time. Daily PM₁₀ decreased from 65.86 μg/m³ during the baseline period to 62.63 μg/m³ during the Asian Games period; daily NO₂ decreased from 51.33 to 42.63 μg/m³. SO₂ and other weather variables did not differ substantially. We did not observe statistically significant improvements in D-dimer levels by 9.86 % from a pre-Asian game mean of 917 ng/ml to a during-Asian game mean of 1007 ng/ml, platelet number by 11.66 %, PH by −0.15 %, PCO₂ by −6.54 %, and PO₂ by −1.16 %. In the post-Asian game period, when pollutant concentrations increased, most outcomes approximated pre-Asian game levels, and similar effects were also demonstrated in D-dimer, platelet number, and arterial blood gas. For D-dimer and platelet number, we observed statistically significant increases associated with increases in NO₂ at lag 1–3 and SO₂ at lag 2–4. For PH, PCO₂, and PO₂, any significant effect was not demonstrated. This study gives no support to the hypothesis that reduction in air pollution levels during the 2010 Asian game is associated with activation of blood coagulation with COPD patients. However, one step forward has been made on the gap between improved air pollution and blood coagulability. Meanwhile, our study also provides evidence for the presence of a hypercoagulative state in systemic circulation in COPD patients. Additional studies employing other susceptible populations and endpoints are pending.
Show more [+] Less [-]Impact of methionine on a partial-nitritation biofilter Full text
2016
Gonzalez-Martinez, Alejandro | Rodriguez-Sanchez, Alejandro | Garcia-Ruiz, Maria Jesus | Osorio, Francisco | Gonzalez-López, Jesús
It has been demonstrated that an anaerobic digestion process cannot attain an efficient removal of several amino acids, with methionine being one of the most persistent of these. Thus, the effect that methionine amino acid has over the partial-nitritation process with fixed-biofilm configuration in terms of performance and bacterial community dynamics has been investigated. With respect to the performance with no addition, 100 mg/L methionine loading decreased ammonium oxidation efficiency in 60 % and 100 % at concentrations of 300 and 500 mg/L methionine, respectively. Bacterial biomass sharply increased by 30, 65, and 230 % with the addition of 100, 300, and 500 mg/L methionine, respectively. Bacterial community analysis showed that methionine addition supported the proliferation of a diversity of heterotrophic genera, such as Lysobacter and Micavibrio, and reduced the relative abundance of ammonium oxidizing genus Nitrosomonas. This research shows that the addition of methionine affects the performance of the partial-nitritation process. In this sense, amino acids can pose a threat for the of partial-nitritation process treating anaerobic digester supernatant at full-scale implementation.
Show more [+] Less [-]Red cabbage yield, heavy metal content, water use and soil chemical characteristics under wastewater irrigation Full text
2016
Tunc, Talip | Sahin, Ustun
The objective of this 2-year field study was to evaluate the effects of drip irrigation with urban wastewaters reclaimed using primary (filtration) and secondary (filtration and aeration) processes on red cabbage growth and fresh yield, heavy metal content, water use and efficiency and soil chemical properties. Filtered wastewater (WW1), filtered and aerated wastewater (WW2), freshwater and filtered wastewater mix (1:1 by volume) (WW3) and freshwater (FW) were investigated as irrigation water treatments. Crop evapotranspiration decreased significantly, while water use efficiency increased under wastewater treatments compared to FW. WW1 treatment had the lowest value (474.2 mm), while FW treatments had the highest value (556.7 mm). The highest water use efficiency was found in the WW1 treatment as 8.41 kg m⁻³, and there was a twofold increase with regard to the FW. Wastewater irrigation increased soil fertility and therefore red cabbage yield. WW2 treatment produced the highest total fresh yield (40.02 Mg ha⁻¹). However, wastewater irrigation increased the heavy metal content in crops and soil. Cd content in red cabbage heads was above the safe limit, and WW1 treatment had the highest value (0.168 mg kg⁻¹). WW3 treatment among wastewater treatments is less risky in terms of soil and crop heavy metal pollution and faecal coliform contamination. Therefore, WW3 wastewater irrigation for red cabbage could be recommended for higher yield and water efficiency with regard to freshwater irrigation.
Show more [+] Less [-]Trace metals in target tissues and stomach contents of the top predator sailfish Istiophorus platypterus from the Eastern Pacific: concentrations and contrasting behavior of biomagnification Full text
2016
Moreno-Sierra, Dalia | Bergés-Tiznado, Magdalena E. | Márquez-Farías, Fernando | Torres-Rojas, Yassir E. | Ruelas-Inzunza, Jorge R. | Páez Osuna, Federico
Cadmium, lead, copper, and zinc were analyzed in the dorsal muscle, liver, gonad, and stomach contents of 67 sailfish, Istiophorus platypterus, from the Eastern Pacific. Muscle exhibited the following pattern (μg/g wet weight): Zn (15.05 ± 1.24) > Cu (0.461 ± 0.026) > Cd (0.434 ± 0.099) > Pb (0.025 ± 0.001); liver Zn (119.1 ± 7.6) > Cd (95.1 ± 11.0) > Cu (39.7 ± 2.6) > Pb (0.047 ± 0.004); and gonad Zn (96.8 ± 7.8) > Cd (2.16 ± 0.38) > Cu (2.08 ± 0.14) > Pb (0.033 ± 0.003). Significant (p < 0.05) correlations were observed between elements, length, and weight. I. platypterus feed mainly on fishes and cephalopods with variable concentrations (μg/g wet weight) of Cd (0.081–11.41), Pb (0.002–0.057), Cu (0.204–4.35), and Zn (3.23–86.6). Of the four analyzed elements, only Pb was biomagnified (BMF = 1.85). According to the regulatory limits, muscle exhibited Cd concentrations higher than the Official Mexican Standard, WHO, FDA (28 % of samples), and the European Union (40 %) regulations.
Show more [+] Less [-]Total, chemical, and biological oxygen consumption of the sediments in the Ziya River watershed, China Full text
2016
Rong, Nan | Shan, Baoqing
Sediment oxygen demand (SOD) is a critical dissolved oxygen (DO) sink in many rivers. Understanding the relative contributions of the biological and chemical components of SOD would improve our knowledge of the potential environmental harm SOD could cause and allow appropriate management systems to be developed. A various inhibitors addition technique was conducted to measure the total, chemical, and biological SOD of sediment samples from 13 sites in the Ziya River watershed, a severely polluted and anoxic river system in the north of China. The results showed that the major component of SOD was chemical SOD due to iron predominate. The ferrous SOD accounted for 21.6–78.9 % of the total SOD and 33.26–96.79 % of the chemical SOD. Biological SOD represented 41.13 % of the overall SOD averagely. Sulfide SOD accounted for 1.78–45.71 % of the total SOD and it was the secondary predominate of the chemical SOD. Manganous SOD accounted for 1.2–16.6 % of the total SOD and it was insignificant at many sites. Only four kinds of benthos were collected in the Ziya River watershed, resulting from the low DO concentration in the sediment surface due to SOD. This study would be helpful for understanding and preventing the potential sediment oxygen depletion during river restoration.
Show more [+] Less [-]Deep learning architecture for air quality predictions Full text
2016
Li, Xiang | Peng, Ling | Hu, Yuan | Shao, Jing | Chi, Tianhe
With the rapid development of urbanization and industrialization, many developing countries are suffering from heavy air pollution. Governments and citizens have expressed increasing concern regarding air pollution because it affects human health and sustainable development worldwide. Current air quality prediction methods mainly use shallow models; however, these methods produce unsatisfactory results, which inspired us to investigate methods of predicting air quality based on deep architecture models. In this paper, a novel spatiotemporal deep learning (STDL)-based air quality prediction method that inherently considers spatial and temporal correlations is proposed. A stacked autoencoder (SAE) model is used to extract inherent air quality features, and it is trained in a greedy layer-wise manner. Compared with traditional time series prediction models, our model can predict the air quality of all stations simultaneously and shows the temporal stability in all seasons. Moreover, a comparison with the spatiotemporal artificial neural network (STANN), auto regression moving average (ARMA), and support vector regression (SVR) models demonstrates that the proposed method of performing air quality predictions has a superior performance.
Show more [+] Less [-]Arsenic and subclinical vascular damage in a sample of Italian young adults: a cross-sectional analysis Full text
2016
Stea, Francesco | Faita, Francesco | Borghini, Andrea | Faita, Francesca | Bianchi, Fabrizio | Bustaffa, Elisa | Minichilli, Fabrizio | Andreassi, Maria Grazia | Sicari, Rosa
Exposure to arsenic (As) increases cardiovascular risk. The purpose of this study was to evaluate the relationship between As and intima-media thickness (IMT) in the common carotid artery and common genetic variants in genes implicated in As metabolism (ASIIIMT Met287Thr, GSTT1+/−, and GSTM1+/−) and DNA repair (hOGG1 Ser326Cys and XRCC1 Arg399Ser). Two hundred and fourteen healthy volunteers, age 20–46, were recruited in four zones polluted by As. Urine samples were tested for total As, inorganic As (iAs), monomethylarsinic (MMA), and dimethylarsinic acid (DMA). Primary and secondary methylation index (PMI, SMI) were computed as MMA/iAs and DMA/MMA. Common carotid artery scans were obtained by high-resolution ultrasound. There was no correlation between IMT and total As, iAs, iAs + MMA + DMA, PMI, or SMI. However, the increase of IMT with age was higher than that observed in the healthy population, both in males (6.25 vs. 5.20 μm/year) and, to a lesser extent, in females (5.05 vs. 4.97 μm/year). After correction for age and gender, subjects with a high urinary As level (≥3.86 μg/L) and carriers of the GSTT1-positive (+) genotype also had higher IMT than those with a low urinary level and the GSTT1-null (−) genotype (0.56 [0.48–0.64] vs. 0.53 [0.44–0.62] mm, p = 0.010). The analysis hints at faster vascular aging as compared to the healthy population. Our findings also suggested that GSTT1 and hOGG1 gene polymorphisms might play an important role in the individual risk of As-induced carotid atherosclerosis.
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