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Modulatory role of vermicompost and vermiwash on growth, yield and nutritional profiling of Linum usitatissimum L. (Linseed): a field study 全文
2019
Makkar, Cinny | Jasawindara Siṅgha, | Parkash, Chander
Vermicompost, recommended inorganic fertiliser, vermiwash and their combinations were used in the present study to know their impact on the germination, growth, yield, oil content and nutritional status in seeds of two varieties of Linum usitatissimum L. LC-54 and LC-2063. Eight treatments, in 48 plots with three replicates, were studied and compared with control. Application of vermicompost enhanced growth and yield in both varieties of Linum. Vermicompost modulated the ratio of ω-3 and ω-6 fatty acids in seeds of Linseed. Growing degree days (GDD) indicated the significantly shortened of crop life cycle with vermiwash. Vermiwash particularly increased the yield indices. Fatty acid profile through GC-FID showed the increase in polyunsaturated fatty acids (ƩPUFA), monounsaturated fatty acids (ƩMUFA) and saturated fatty acids (ƩSFA) with Integrated Nutrient Management (INM). Different effects on nutritional status of LC-54 and LC-2063 seeds can be attributed to their unique genotypes. INM proved to be nutritionally balanced strategy with enhanced yield leading to better soil health. INM can be hypothesised as a transitional step to the organic agriculture after the green revolution, when compared with recommended inorganic fertiliser treatment and control. In terms of oil yield, highest oil content 34.85% and 33.67% was obtained with Integrated Nutrient Management in both the varieties, whereas treatments with vermicompost and vermiwash produced modulated and most suited ratio of omega-3 and omega-6 in Linseed seeds.
显示更多 [+] 显示较少 [-]Application of emulsion and Pickering emulsion liquid membrane technique for wastewater treatment: an overview 全文
2019
Hussein, Maad A. | Mohammed, Ahmed A. | Atiya, Mohammed A.
According a wide range of relevant literature, the emulsion liquid membrane technique (ELM) is considered an efficient method to separate and recover organic and inorganic contaminants that could otherwise be released into the environment. One important limitation of ELM process concerns the stabilization and de-stabilization of emulsion globules. To address this, over the last few years, a new ELM trend known as the Pickering emulsion liquid membrane (PELM) has been developed. PELM involves nanoparticle concepts to achieve a more stable emulsion for wastewater treatment. In this article, ELM and PELM techniques, preparation methods, characteristics, stabilization methods (i.e., mechanical and ultrasound emulsification), and de-stabilization (i.e., swelling, leakage and coalescence) of the emulsion are reviewed and described. In addition, various parameters that could impact ELM stability, extraction, and recovery, such as emulsification speed and time, surfactant, carrier, internal agent, diluent, stirring speed, internal to membrane ratio, type of organic membrane, and treatment ratio, are also presented and discussed.
显示更多 [+] 显示较少 [-]Life cycle assessment of autoclaved aerated fly ash and concrete block production: a case study in China 全文
2019
Shi, Yifei | Li, Yue | Tang, Yuzhou | Yuan, Xueliang | Wang, Qingsong | Hong, Jinglan | Zuo, Jian
With the rapid development of construction industry, consumption of concrete block has increased rapidly in China. As a kind of green building material and resource comprehensive utilization product, autoclaved aerated fly ash and concrete block have better performance in terms of heat preservation, sound insulation, and fire resistance. However, some typical issues are associated with autoclaved aerated fly ash and concrete block production process such as energy and material consumption as well as pollutant emissions. To examine the environmental and economic impacts of its production process is imperative. Choosing 1 m³ of autoclaved aerated fly ash and concrete block product as functional unit and “cradle to gate” as system boundary, a life cycle inventory is developed. The key processes and key materials with significant environmental impact are identified. Results show that the top four environmental impact categories are marine ecotoxicity, freshwater ecotoxicity, freshwater eutrophication, and human toxicity. Key processes are fly ash slurry production, lime grinding, and steam curing processes. These processes account for 46.58%, 26.00%, and 19.62% of the total environmental load respectively. The key materials are cement, lime, and natural gas, which account for 44.91%, 22.79%, and 20.61% respectively of overall environmental impact. Sensitivity analysis shows that the fly ash slurry production should be optimized preferentially, followed by lime grinding and steam curing processes. These findings are helpful to facilitate the sustainable production of autoclaved aerated fly ash and concrete block.
显示更多 [+] 显示较少 [-]Photocatalytic removal of trichloroethylene from water with LaFeO3 全文
2019
Xu, Yanzhen | Chang, Shu-Hao | Chung, Wei-Chieh | Chang, Moo-Been
Tricholorethylene (TCE) has been recognized as second common organic pollutant found in groundwater in Taiwan. Several advanced oxidation processes (AOPs) have been applied for TCE removal and photocatalytic is one of promising AOP techniques. In this study, LaFeO₃ is successfully synthesized via sol-gel method and investigated for its photocatalytic oxidation rate toward TCE in water. Experimental results indicate that 95% removal efficiency of TCE can be achieved in aqueous solution with LaFeO₃ (2 g/L) as photocatalyst within 1 h of Xenon lamp illumination. Additionally, the influences of initial TCE concentration, light intensity, photocatalyst loading, and pH value on the TCE removal efficiency are evaluated as well. The highest energy efficiency obtained in this study is 10.8 mg TCE/kWh and the value is higher than those reported in previous studies. Besides, removal mechanisms have been identified and the results indicate that the overall removal efficiency reaches 82%, with adsorption and photolysis accounting for 20% and 39%, respectively.
显示更多 [+] 显示较少 [-]Low blood lead levels and attention-deficit hyperactivity disorder in children: a systematic review and meta-analysis 全文
2019
He, Jianjun | Ning, Huacheng | Huang, Ruixue
Attention-deficit hyperactivity disorder (ADHD) of children is one of the most common neurodevelopmental diseases; the etiology remains unclear. We reviewed and meta-analyzed case-control studies to assess the effects of blood lead levels in children on ADHD symptoms. Relevant studies were identified by searching electronic databases. A meta-analysis was performed using the fixed model of Review Manager 5.3 software. Seven relevant studies were identified. The case groups exhibited significant increases in ADHD symptoms [mean difference (MD), 0.59; 95% confidence interval (CI), 0.50–0.68; p < 0.0001]. Subgroup assessment showed that even children with blood lead levels <3 μg/dL exhibited significant increases in ADHD symptoms (MD, 0.47; 95% CI, 0.39–0.56; p < 0.0001). Subgroup assessment also showed that children aged 5–12 years exhibited more significant increases in ADHD symptoms (MD, 1.35; 95% CI, 0.28–2.41; p < 0.0001) than children aged >12 years. Our findings suggest that low blood lead levels may be associated with ADHD symptoms in children. However, caution is needed when interpreting the results because among-study heterogeneity was in play. Primary interventions should focus on children with low blood lead levels.
显示更多 [+] 显示较少 [-]Regional environmental regulation efficiency: spatiotemporal characteristics and influencing factors 全文
2019
Du, Yu | Peng, Benhong | Wei, Guo | Elahi, Ehsan | Yu, Tongrui
Research regarding the regional environmental regulation efficiency (ERE) and influencing factors can provide theoretical guidance for regions to improve their ERE effectively. By employing a two-step approach, the data envelopment analysis (DEA) CCR-BCC model is built with the inclusion of scale changes, and a Tobit model is developed to explore the influencing factors for the regional ERE, followed by an application to analyze the spatiotemporal variations of ERE in Jiangsu province from 2005 to 2015. It is found that in time dimension, the ERE lies generally in a weak effective interval of [0.5, 1) and displays a shock upward trend. In the spatial dimension, the ERE presents an obvious “bilateral effect”, namely, the efficiency is high for both the southern and northern of Jiangsu province but lower for the middle area. Besides, GDP per capital, industrial structure, trade openness, and population growth are among the main influencing factors of ERE. The findings revealed that temporary short-term policies have noticeable impact on the regional ERE, and “matching effect” between the ERE and regional economic development does not present.
显示更多 [+] 显示较少 [-]Neonicotinoid insecticide design: molecular docking, multiple chemometric approaches, and toxicity relationship with Cowpea aphids 全文
2019
Bora, Alina | Suzukiski, | Funar-Timofei, Simona
Neonicotinoids are the fastest-growing class of insecticides successfully applied in plant protection, human and animal health care. The significant resistance increases led to the urgent need for alternative new neonicotinoids, with improved insecticidal activity. We performed molecular docking to describe a common binding mode of neonicotinoids into the nicotinic acetylcholine receptor, and to select the appropriate conformations to derive models. These were further used in a QSAR study employing both linear and nonlinear approaches to model the inhibitory activity against the Cowpea aphids. Linear modeling was performed by multiple linear regression and partial least squares and nonlinear modeling by artificial neural networks and support vector machine methods. The OECD principles were considered for QSAR models validation. Robust models with predictive power were found for neonicotinoid diverse structures. Based on our QSAR and docking outcomes, five new insecticides were predicted, according to the model applicability domain, the ligand efficiencies, and the binding mode. Therefore, the developed models can be confidently used for the prediction of the insecticidal activity of new chemicals, saving a substantial amount of time and money and, also, contributing to the chemical risk assessment.
显示更多 [+] 显示较少 [-]Monitoring the morphological integrity of neotropical anurans 全文
2019
Borges, Rinneu Elias | de Souza Santos, Lia Raquel | Assis, Rhayane Alves | Benvindo-Souza, Marcelino | Franco-Belussi, Lilian | de Oliveira, Classius
Amphibians are considered to be excellent bioindicators to their morphophysiological characteristics and life cycle. In this context, the present study investigated the morphological integrity of anuran larvae collected in preserved environments in the Emas National Park, in the municipality of Mineiros (Goiás state, Brazil), and in environments representative of the agricultural matrix of the Rio Verde region, also in Goiás, where there is a long history of the use of agricultural pesticides. Samples of water from temporary ponds, permanent dams, and veredas were analyzed for the presence of pesticides and, especially atrazine (5350 μg/L), found at significantly higher concentrations in the agricultural matrix. We observed a high percentage (approximately 10%) of morphological malformations including alterations of the fins in Boana albopunctatus and Scinax fuscovarius; alteration in oral structures in B. albopunctatus, Dematonotus muelleri, Physalaemus centralis, Physalaemus cuvieri, and Leptodactylus fuscus mainly in the tadpoles collected in the agricultural environment in comparison with those from the protected area (3.5%; P < 0.0001, χ² 31.75). However, changes in the eyes, mouth, intestines, and nostrils, as well as amelia were observed only in the agricultural environment. The vast majority of the observed malformations were associated with the tail and oral disc, which suggests that these anatomical parameters may be used as sensitive morphological biomarkers. Given these findings, we reinforce that areas of agricultural land may have a deleterious effect on the morphological integrity of the tadpoles and consequently, on their development, and that these features may be used as indicators of environmental quality and health.
显示更多 [+] 显示较少 [-]An analysis of the dust deposition on solar photovoltaic modules 全文
2019
Styszko, Katarzyna | Jaszczur, Marek | Teneta, Janusz | Hassan, Qusay | Burzyńska, Paulina | Marcinek, Ewelina | Łopian, Natalia | Samek, Lucyna
Solid particles impair the performance of the photovoltaic (PV) modules. This results in power losses which lower the efficiency of the system as well as the increases of temperature which additionally decreases the performance and lifetime. The deposited dust chemical composition, concentration and formation of a dust layer on the PV surface differ significantly in reference to time and location. In this study, an evaluation of dust deposition on the PV front cover glass during the non-heating season in one of the most polluted European cities, Kraków, was performed. The time-dependent particle deposition and its correlation to the air pollution with particulate matter were analysed. Dust deposited on several identical PV modules during variable exposure periods (from 1 day up to 1 week) and the samples of total suspended particles (TSP) on quartz fibre filters using a low volume sampler were collected during the non-heating season in the period of 5 weeks. The concentration of TSP in the study period ranged between 12.5 and 60.05 μg m⁻³ while the concentration of PM10 observed in the Voivodeship Inspectorate of Environmental Protection traffic station, located 1.2 km from the TSP sampler, ranged from 14 to 47 μg m⁻³. It was revealed that dust deposition density on a PV surface ranged from 7.5 to 42.1 mg m⁻² for exposure periods of 1 day while the measured weekly dust deposition densities ranged from 25.8 to 277.0 mg m⁻². The precipitation volume and its intensity as well as humidity significantly influence the deposited dust. The rate of dust accumulation reaches approximately 40 mg m⁻²day⁻¹ in the no-precipitation period and it was at least two times higher than fluxes calculated on the basis of PM10 and TSP concentrations which suggest that additional forces such as electrostatic forces significantly influence dust deposition.
显示更多 [+] 显示较少 [-]Dynamics of oxytetracycline and resistance genes in soil under long-term intensive compost fertilization in Northern China 全文
2019
Wu, Ming | Han, Hui | Zheng, Xiangnan | Bai, Mohan | Xu, Ting | Ding, Guo-chun | Li, Ji
In the present study, we explored the dynamics of antibiotics (ciprofloxacin, norfloxacin, enrofloxacin, and oxytetracycline), tetracycline resistance genes (TRGs), and bacterial communities over 2013–2015 in soils fertilized conventionally or with two levels (82.5 and 165 t/ha) of compost for 12 years. In the soil receiving 165 t/ha of compost, only oxytetracycline was 46% higher than that in the conventionally fertilized soil. Transient enrichment of both tetM (20% to 9-fold) and tetK (25% to 67-fold) was observed in multiple instances immediately after the application of compost. The majority of genera which positively correlated with tetM or tetK were affiliated to Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes. The structural equation model analysis indicated that fertilization regimes directly affected the bacterial composition and antibiotics and had an indirect effect on the abundance of tetK and tetM via these antibiotics. In summary, this study shed light into the complex interactions between fertilization, antibiotics, and antibiotic resistance pollution in greenhouse soil.
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