细化搜索
结果 3031-3040 的 4,308
A bibliometric analysis of research on haze during 2000–2016 全文
2017
Li, Chenxi | Wu, Kening | Wu, Jingyao
As one of the bibliometric analysis tools, CiteSpace software was applied to quantitatively and visually evaluate global scientific documents of research on haze from 2000 to 2016. Five thousand six hundred six documents from the Science Citation Index Expanded (SCI-Expanded) and Social Science Citation Index (SSCI) of the Web of Science database were statistically analyzed and examined. The distributions on authorship, countries/territories, institutes, and keywords were generated. The amount of publications has increased nearly for the past 17 years. The most productive author was Li J. with 46 articles. The publications on haze research were primarily originated from the USA, China, Germany, and France. By synthetically analyzing the keywords, the dominant hot spots of haze research could be concluded as “aerosol,” “atmosphere,” “particle,” “PM₂.₅,”and “air quality.”
显示更多 [+] 显示较少 [-]Forest Stewardship Council (FSC) pesticide policy and integrated pest management in certified tropical plantations 全文
2017
Lemes, Pedro Guilherme | Zanuncio, José Cola | Serrão, José Eduardo | Lawson, Simon A.
The Forest Stewardship Council (FSC) was the first non-governmental organization composed of multi-stakeholders to ensure the social, environmental, and economic sustainability of forest resources. FSC prohibits certain chemicals and active ingredients in certified forest plantations. A company seeking certification must discontinue use of products so listed and many face problems to comply with these constraints. The aim of this study was to assess the impacts of certification on pest management from the perspective of Brazilian private forestry sector. Ninety-three percent of Brazilian FSC-certified forest companies rated leaf-cutting ants as “very important” pests. Chemical control was the most important management technique used and considered very important by 82 % of respondents. The main chemical used to control leaf-cutting ants, sulfluramid, is in the derogation process and was classified as very important by 96.5 % of the certified companies. Certified companies were generally satisfied in relation to FSC certification and the integrated management of forest pests, but 27.6 % agreed that the prohibitions of pesticides for leaf-cutting ant and termite control could be considered as a non-tariff barrier on high-productivity Brazilian forest plantations. FSC forest certification has encouraged the implementation of more sustainable techniques and decisions in pest management in forest plantations in Brazil. The prohibition on pesticides like sulfluramid and the use of alternatives without the same efficiency will result in pest mismanagement, production losses, and higher costs. This work has shown that the application of global rules for sustainable forest management needs to adapt to each local reality.
显示更多 [+] 显示较少 [-]Biochars mitigate greenhouse gas emissions and bioaccumulation of potentially toxic elements and arsenic speciation in Phaseolus vulgaris L 全文
2017
Ibrahim, Muhammad | Li, Gang | K̲h̲ān, Sardār | Chi, Qiaoqiao | Xu, Yaoyang
Anthropogenic and natural activities can lead to increased greenhouse gas emissions and discharge of potentially toxic elements (PTEs) into soil environment. Biochar amendment to soils is a cost-effective technology and sustainable approach used to mitigate greenhouse gas emissions, improve phytoremediation, and minimize the health risks associated with consumption of PTE-contaminated vegetables. Greenhouse pot experiments were conducted to investigate the effects of peanut shell biochar (PNB) and sewage sludge biochar (SSB) on greenhouse gas (GHG) emissions, plant growth, PTE bioaccumulation, and arsenic (As) speciation in bean plants. Results indicated that amendments of PNB and SSB increased plant biomass production by increasing soil fertility and reducing bioavailability of PTEs. Addition of biochars also increased soil pH, total nitrogen (TN), total carbon (TC), dissolved organic carbon (DOC), and ammonium-nitrogen (NH₄-N) but decreased available concentrations of PTEs such as cadmium (Cd), lead (Pb), and As. The concentration of nitrate-nitrogen (NO₃⁻-N) was also decreased in biochar-amended soils. In addition, PNB and SSB amendments significantly (P < 0.01) reduced the bioaccumulation of chromium (Cr), As, Cd, Pb, and nickel (Ni) in stalks, leaves, and fruits of Phaseolus vulgaris L. Similarly, PNB and SSB amendments significantly (P ≤ 0.05) reduced inorganic As species like arsenite (As (III)) and arsenate (As (V)). Greenhouse gases such as carbon dioxide (CO₂) and methane (CH₄) emissions were significantly (P < 0.01) reduced but nitrous oxide (N₂O) emissions first increased and then decreased amended with both biochars. Current findings demonstrate that SSB and PNB are two beneficial soil amendments simultaneous mitigating greenhouse gas emissions and PTE bioaccumulation as well as arsenic speciation in P. vulgaris L.
显示更多 [+] 显示较少 [-]Kinetics, isotherm, and thermodynamic studies of methylene blue adsorption from water by Mytella falcata waste 全文
2017
Silva, TársilaS. | Meili, Lucas | Carvalho, SandraHelena V. | Soletti, JoãoInácio | Dotto, GuilhermeLuiz | Fonseca, EduardoJorge S.
This work evaluates the application of Mytella falcata shells, discarded in large quantities in the state of Alagoas, Brazil, as adsorbent for methylene blue dye (MB). It was investigated how the amount of adsorbent (M), the average particle diameter (G), and the agitation speed (A) affected the adsorption. Kinetic and equilibrium studies were conducted, and the pseudo-second-order equation adequately represented the kinetic data and isotherms following Liu’s model (q ₘₐₓ = 8.81 mg g⁻¹ at 60 °C). The adsorption was spontaneous, favorable, and endothermic. Mytella falcata shell is a suitable adsorbent for MB and could potentially contribute to its removal from the environment.
显示更多 [+] 显示较少 [-]Biosurfactants during in situ bioremediation: factors that influence the production and challenges in evalution 全文
2017
Decesaro, Andressa | Machado, ThaísStrieder | Cappellaro, ÂngelaCarolina | Reinehr, ChristianOliveira | Thomé, Antônio | Colla, LucianeMaria
Research on the influence of biosurfactants on the efficiency of in situ bioremediation of contaminated soil is continuously growing. Despite the constant progress in understanding the mechanisms involved in the effects of biosurfactants, there are still many factors that are not sufficiently elucidated. There is a lack of research on autochthonous or exogenous microbial metabolism when biostimulation or bioaugmentation is carried out to produce biosurfactants at contaminated sites. In addition, studies on the application of techniques that measure the biosurfactants produced in situ are needed. This is important because, although the positive influence of biosurfactants is often reported, there are also studies where no effect or negative effects have been observed. This review aimed to examine some studies on factors that can improve the production of biosurfactants in soils during in situ bioremediation. Moreover, this work reviews the methodologies that can be used for measuring the production of these biocomposts. We reviewed studies on the potential of biosurfactants to improve the bioremediation of hydrocarbons, as well as the limitations of methods for the production of these biomolecules by microorganisms in soil.
显示更多 [+] 显示较少 [-]Historical record of nutrients inputs into the Xin’an Reservoir and its potential environmental implication 全文
2017
Jia, Xiaobin | Luo, Wenyun | Wu, Xueqian | Wei, Haobin | Wang, Baoli | Phyoe, Waiwai | Wang, Fushun
The Xin’an Reservoir is an important water supply source and water conservation area for the Qiantang River. However, after the occurrence of the two algae blooms in 1998 and 1999, the safety of water quality has been put into question. In order to study the historical deposition of nutrients, sediment cores were collected in different regions from the Xin’an Reservoir. The stable isotopes δ¹³C and δ¹⁵N, nutrients, total organic carbon (TOC), and inorganic carbon (IC) in the sediment cores were determined. Radiometric methods (²¹⁰Pb and ¹³⁷Cs) were used to obtain sediment chronologies. Spatially, it was found that the average total nitrogen (TN) content in the upper 5 cm of sediments increased from 0.21% in the riverine zone, to 0.33%, and then to 0.57% in the lacustrine zone. The average TP content in the upper 5 cm increased from 0.67 g kg⁻¹ in the riverine zone, to 1.03 g kg⁻¹ in the estuary region, and then to 1.65 g kg⁻¹ in the lacustrine zone. In addition, TOC levels showed a distinct increase from 1.42% in the bottom to 5.97% in the surface of the lacustrine zone. These results demonstrated that although primary productivity and the input of nutrients constantly increased in recent years, algae blooms rarely occurred in the Xin’an Reservoir, due to “depth effect” and an aquatic environment protection-oriented fishery policy. However, high TOC flux and high bio-available phosphorus and nitrogen in surface sediment demonstrated that the reservoir is still confronted with the potential risk of algae blooms.
显示更多 [+] 显示较少 [-]Generation and management of waste electric vehicle batteries in China 全文
2017
Xu, ChengJian | Zhang, Wenxuan | He, Wenzhi | Li, Guangming | Huang, Juwen | Zhu, Haochen
With the increasing adoption of EVs (electric vehicles), a large number of waste EV LIBs (electric vehicle lithium-ion batteries) were generated in China. Statistics showed generation of waste EV LIBs in 2016 reached approximately 10,000 tons, and the amount of them would be growing rapidly in the future. In view of the deleterious effects of waste EV LIBs on the environment and the valuable energy storage capacity or materials that can be reused in them, China has started emphasizing the management, reuse, and recycling of them. This paper presented the generation trend of waste EV LIBs and focused on interrelated management development and experience in China. Based on the situation of waste EV LIBs management in China, existing problems were analyzed and summarized. Some recommendations were made for decision-making organs to use as valuable references to improve the management of waste EV LIBs and promote the sustainable development of EVs.
显示更多 [+] 显示较少 [-]Release of phosphorus from sewage sludge during ozonation and removal by magnesium ammonium phosphate 全文
2017
The release rule of phosphorus from sewage sludge during ozonation and removal by the magnesium ammonium phosphate (MAP) method were investigated. The results showed that the concentrations of total phosphorus in aqueous phase (TP₍A₎) and orthophosphate (PO₄ ³⁻-P) in ozonized sludge supernatant rose obviously with increasing ozone dose when ozone dose was below 61.2 mg O₃/gSS then almost kept constant. The TP₍A₎ and PO₄ ³⁻-P contents in the ozonized sludge supernatant were 70.9 and 63.3 mg/L when ozone dose was 61.2 mg O₃/gSS, respectively. Total phosphorus in the sludge solid (TP₍S₎) was mostly distributed in inorganic phosphorus (IP) (more than 81.5% of TP₍S₎), and non-apatite inorganic phosphorus (NAIP) was the major component of IP in the sludge (more than 78.7% of IP) during ozonation. The release contribution (RC) of IP to TP₍A₎ accounted for over 73.9%. The optimized conditions for the removal of phosphorus from ozonized sludge supernatant were set at an initial Mg²⁺/PO₄ ³⁻-P molar ratio of 1.8, pH 9.5, and reaction time of 5 min, under which the removal efficiencies of TP₍A₎ and PO₄ ³⁻-P were 43.1 and 52.2%, respectively.
显示更多 [+] 显示较少 [-]Modeling of policies for reduction of GHG emissions in energy sector using ANN: case study—Croatia (EU) 全文
2017
This study describes the development of tool for testing different policies for reduction of greenhouse gas (GHG) emissions in energy sector using artificial neural networks (ANNs). The case study of Croatia was elaborated. Two different energy consumption scenarios were used as a base for calculations and predictions of GHG emissions: the business as usual (BAU) scenario and sustainable scenario. Both of them are based on predicted energy consumption using different growth rates; the growth rates within the second scenario resulted from the implementation of corresponding energy efficiency measures in final energy consumption and increasing share of renewable energy sources. Both ANN architecture and training methodology were optimized to produce network that was able to successfully describe the existing data and to achieve reliable prediction of emissions in a forward time sense. The BAU scenario was found to produce continuously increasing emissions of all GHGs. The sustainable scenario was found to decrease the GHG emission levels of all gases with respect to BAU. The observed decrease was attributed to the group of measures termed the reduction of final energy consumption through energy efficiency measures.
显示更多 [+] 显示较少 [-]Oxidative and cellular stress as bioindicators for metal contamination in freshwater mollusk Lamellidens marginalis 全文
2017
The concentrations of 14 metals, namely, chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), selenium (Se), arsenic (As), strontium (Sr), cadmium (Cd), tin (Sn), antimony (Sb), mercury, (Hg), and lead (Pb), have been studied in freshwater mollusk Lamellidens marginalis collected from Dhimbe reservoir. In addition, also studied the cellular and antioxidative status to assess metal contamination as pollution biomarkers. The levels of all the 14 metals were elevated in different sampling sites of Dhimbe reservoir. The level of metals in the L. marginalis was followed as Mn > Zn > Ni > Sr > Cr > Cu > Hg > Se > Sn > Pb > As > Co > Cd > Sb. The oxidative biomarkers viz. catalase (CAT), superoxide dismutase (SOD), and glutathione-S-transferase (GST); glycolytic enzymes viz. lactate dehydrogenase (LDH) and malate dehydrogenase (MDH); and protein metabolic enzymes viz. aspartate amino transferase (AST), alanine amino transferase (ALT), and lipid peroxidation (LPO) were significantly (p < 0.01) higher, while neurotransmitter enzymes such as acetylcholine esterase (AChE) were significantly inhibited in muscle of L. marginalis (p < 0.01) collected from different sampling sites. Therefore, based on our results, we could recommend that the Dhimbe reservoir is moderately metal contaminated and investigation based on biochemical parameters such as antioxidative enzymes, cellular biomarkers, and AChE are strong indicators for metal contamination; hence, these parameters are successfully applied as reliable biomarkers for monitoring contaminated freshwater ecosystems.
显示更多 [+] 显示较少 [-]