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Industrial growth, clean energy generation, and pollution: evidence from top ten industrial countries Texto completo
2021
Kahia, Montassar | Ben Jebli, Mehdi
Unlike the previous study, this paper employs panel cointegration and Granger causation approaches to discuss the associations among carbon dioxide (CO₂) emissions, GDP growth, clean energy generation, and industrial growth for the top ten industrial countries spanning the period 1980-2014. The primary empirical outcomes show a two-way long-run association between environmental indicator, GDP growth, and clean energy generation, while one short-run causation from clean energy generation to CO₂ emissions and from industrial growth to clean energy generation. The computed coefficients elasticity’s under FMOLS, DOLS, and CCR estimates revealed that the clean energy generation statistically contributes to declining emissions of CO₂ in Australia, Austria, and Chile while statistically increase emissions of CO₂ in Denmark and the Netherlands. Industrial growth statistically contributes to reducing emissions of CO₂ in Denmark and Norway but increases emissions in Chile, France, and Sweden. For the global panel, industrial growth leads to mitigate the rate of emissions while clean energy generation raises CO₂ emissions in the long period. Investing in clean energy is needed to stimulate the growth of the industrial sector and then reduce the rate of emissions.
Mostrar más [+] Menos [-]Bioaugmentation mitigates ammonia and hydrogen sulfide emissions during the mixture compost of dewatered sewage sludge and reed straw Texto completo
2021
Cheng, Qingli | Zhang, Longlong | Wang, Dawei | Niu, Bochao
This study investigated the effectiveness of bio-augmenting aerobic cell culture to mitigate ammonia and hydrogen sulfide emission in sewage sludge composting amended with reed straw (with the weight ratio of 1:0.3–0.4). During the 20-day aerated lab-scale composting, adding 200-mL culture (56.80 NTU) reduced ammonia and hydrogen sulfide emissions by 38.00% and 54.32%, and conserved total nitrogen and sulfate by 39.42% and 70.75%, respectively. Organic matters degradation was quick started 1 day ahead. Comparing to the control, nitrate content increased 38.75% at the end of the compost. Bioaugmentation evened the distributions of bacterial communities in the thermophilic phase. The shift was mainly due to 22.97% of relative abundance of Proteobacteria depressed and 157.16% of Bacteroidetes increased, which were beneficial for nitrogen conservation and glycan breakdown, respectively. In summary, the results demonstrated that bioaugmentation addition could be an effective strategy for enhanced sludge composting.
Mostrar más [+] Menos [-]Low-cost sensor system for monitoring the oil mist concentration in a workshop Texto completo
2021
Zhang, Hongsheng | Zhang, Siyi | Pan, Wuxuan | Long, Zhengwei
Metalworking fluids used in industrial workshops may present a major threat to the health of workers who have been exposed to a high oil mist concentration over a long period of time. Therefore, monitoring the temporal and spatial distribution of particulate matter concentration has great practical significance for the control of oil mist. Traditional particle monitors are generally cumbersome, expensive, and difficult to maintain, which to some extent restricts their extensive use in workshops. Recent years have witnessed tremendous developments in the area of low-cost sensors, which are of great help in obtaining high-density pollution data. In this paper, we evaluate the performance of an inexpensive laser sensor (A4-CG) during long-term oil mist monitoring in a machine shop for the first time. With the use of Lora technology, we developed an online oil mist monitoring network to access real-time concentration, temperature, and humidity information from distributed monitors. According to the results, the sensor data correlated well with measurements by the reference instrument (R² = 0.96), which means that the distributed sensor network can accurately detect the concentration level of oil mist in the workshop. In fact, most of the sensors demonstrated stable operation for up to half a year according to cluster analysis, while several sensors exhibited serious data drift. Furthermore, the results indicate that the peak oil mist concentration in most areas during production exceeded the value of 0.5 mg m⁻³ recommended by NIOSH, and it was found that appropriately lowering the relative humidity can make sampling more accurate, while lowering the temperature can reduce the oil mist concentration in the workshop. Thus, measures to control oil mist such as generation and distribution of pollution sources should be on the agenda.
Mostrar más [+] Menos [-]Wastewater analysis reveals urban, suburban, and rural spatial patterns of illicit drug use in Dalian, China Texto completo
2021
Cong, Zi-Xiang | Shao, Xue-Ting | Liu, Si-Yu | Pei, Wei | Wang, De-Gao
Illicit drug use in rural and suburban areas of China has not been studied extensively, as most studies have focused on illicit drug use in urban areas. To compare the differences between urban, suburban, and rural drug use, we collected influent samples from 19 urban, 9 suburban, and 18 rural wastewater treatment plants in Dalian, respectively. A method using solid-phase extraction combined with derivatization for gas chromatography -mass spectrometry analysis was applied to detect biomarker concentrations. The concentrations of methamphetamine and morphine ranged from 3.12 to 605 ng/L and < 2.35 to 198 ng/L, respectively. Norketamine was found in only four samples (5.56 to 14.5 ng/L), while 3,4-methylenedioxymethamphetamine and benzoylecgonine were not detected in any samples. Methamphetamine use in rural areas (16.3 mg/day/1000 inhabitant (inh), prevalence: 0.06%) was significantly lower than those in urban (77.1 mg/day/1000 inh, prevalence: 0.23%) and suburban (234 mg/day/1000 inh, prevalence: 0.70%) areas. Heroin use in suburban areas (57.6 mg/day/1000 inh, prevalence: 0.10%) was significantly higher than that in urban (13.9 mg/day/1000 inh, prevalence: 0.02%) and rural (8.68 mg/day/1000 inh, prevalence: 0.02%) areas. The results indicate relatively low levels of illicit drug use in rural areas of Dalian, related to low incomes and outflow of the working-age population. Illicit drug use was most prevalent in suburban areas of Dalian, which may be influenced by large floating populations and few anti-drug efforts in suburban areas.
Mostrar más [+] Menos [-]The regulatory role of root in cadmium accumulation in a high cadmium-accumulating rice line (Oryza sativa L.) Texto completo
2021
Yu, Haiying | Wang, Keji | Huang, Huagang | Zhang, Xizhou | Li, Tingxuan
There are some key processes that regulate cadmium (Cd) accumulation in rice. Understanding the characteristics and mechanisms of Cd accumulation in high Cd-accumulating rice lines benefits for excavating relevant genes. Cd accumulation and distribution in roots of Lu527-8, a high Cd-accumulating rice line, were investigated by a hydroponic experiment, with a control of a normal rice line (Lu527-4). Lu527-8 showed significantly higher Cd concentrations in roots than Lu527-4. More than 81% of Cd in roots of two rice lines is distributed in soluble fraction and cell wall. In soluble fraction, there were more organic acids, amino acids, and phytochelatins in Lu527-8, benefiting Cd accumulation. Pectin and hemicellulose 1 (HC1), especially pectin, were main polysaccharides in cell wall. Lu527-8 showed more pectin and HC1 along with higher pectin methylesterase (PME) activity compared with Lu527-4, promoting Cd accumulation. Besides, Lu527-8 showed higher Cd translocation from root to shoot due to more amounts of ethanol-extractable Cd in roots than Lu527-4. In conclusion, specific characteristics of Cd chemical forms and subcellular distribution in roots of high Cd-accumulating rice line are important for Cd accumulation and translocation.
Mostrar más [+] Menos [-]Impact of cadmium on forage kale (Brassica oleracea var. viridis cv “Prover”) after 3-,10- and 56-day exposure to a Cd-spiked field soil Texto completo
2021
Bernard, Fabien | Dumez, Sylvain | Lemière, Sébastien | Platel, Anne | Nesslany, Fabrice | Deram, Annabelle | Vandenbulcke, Franck | Cuny, Damien
Cadmium (Cd) is a highly toxic element for living organisms and is widespread in metal-contaminated soils. As organisms which can grow up on these polluted areas, plants have some protection mechanisms against Cd issues. Among the plant kingdom, the Brassicaceae family includes species which are known to be able to tolerate and accumulate Cd in their tissues. In this study, Brassica oleracea var. viridis cv “Prover” was exposed to a range of artificially Cd-contaminated soils (from 2.5 up to 20 mg kg⁻¹) during 3, 10, and 56 days and the effects on life traits, photosynthesis activity, antioxidant enzymatic activities were studied. Metal accumulation was quantified, as well as DNA damage, by means of the comet assay and immunodetection of 8-OHdG levels. Globally, B. oleracea was relatively tolerant to those Cd exposures. However, comet assay and detection of 8-OHdG revealed some DNA damage but which are not significant. According to metal accumulation analysis, B. oleracea var. viridis cv Prover could be a good candidate for alternative growing in contaminated areas.
Mostrar más [+] Menos [-]The scientometric analysis of the research on microalgae-based wastewater treatment Texto completo
2021
Li, Zhuo | Zhu, Liandong
This study explores the characteristics of the literature on microalgae-based wastewater treatment during the past 20 years, based on the Web of Science Core Collection database and its scientometric techniques. The results reveal that the literature on microalgae-based wastewater treatment has grown rapidly with 2621 publications and 54,388 citations in total. Most of the document types are journal articles, constituting 80.7% of the total records. China and the USA are the two most active countries, regarding the publications and cooperation in this filed from the viewpoint of the number of publishing papers, total number of citations, and the number of multinational author papers. The Chinese Academy of Sciences is the largest institutional contributor, publishing 2.3% of the papers, followed by the Indian Institute of Technology (2.2%) and Council of Scientific & Industrial Research (2.1%). The most publishing author is Ruan (35 papers) with the highest number of citation (2460 times). “Bioresource Technology” is the most publishing journal with 365 published papers, while 36.2% of the total sample is published in the subject area of “Environmental Sciences Ecology.” The most cited paper in the past 20 years is a review of the status of phosphorus removal in wastewater by de-Bashan in 2004. Bibliometric analysis has systematically combed the development system of microalgae-based wastewater treatment in the past 20 years and has a great potential to gain valuable insights for the future development, which provides a supplement to the common content analysis.
Mostrar más [+] Menos [-]Preservative potential of biosynthesized silver nanoparticles: prevention of xylem occlusion and microbial proliferation at postharvest stage of preservation Texto completo
2021
Das, Dipayan | Ghosh, Debasmita | Mandal, Palash
The purpose of the current study was to determine the appropriate genotype and concentration of biosynthesized silver nanoparticles effectual in preserving mulberry leaves at the postharvest stage. The preservative effect of silver nanoparticles was determined by their potentiality to prevent xylem blockage, chlorophyll content retention and inhibition of microbial proliferation within a preservative solution. For synthesizing silver nanoparticles, a blend of 10⁻³ M silver nitrate and S1 genotype of the mulberry leaf was found to be most effective. Silver nanoparticles at 6 ppm were observed to be the least effective concentration for preserving mulberry leaves for at least 7 days at the postharvest stage, as evident from physical texture and retention of chlorophyll content. Biosynthesized silver nanoparticles showed negative microbial count during the course of preservation as evident from no colony-forming unit (CFU) until the last day of preservation, while conventional preservative silver nitrate showed traces of CFU on a nutrient agar plate. Besides, these leaves preserved in nanosilver solution showed an almost negligible number of xylem blockage in the petiole, almost equivalent to the blockage nature of fresh leaves caused by the deposition of macromolecules like protein, lignin and suberin. Nanosilver- and silver nitrate–preserved leaves also displayed insignificant accumulation of reactive oxygen species (ROS) and greater retention of membrane integrity than leaves preserved in normal distilled water. Nanosilver solution showed greater durability of preserving mulberry leaves than conventional floral preservative silver nitrate, useful for feeding silkworm larvae during the rainy season.
Mostrar más [+] Menos [-]Detecting urban landscape factors controlling seasonal land surface temperature: from the perspective of urban function zones Texto completo
2021
Li, Tong | Xu, Ying | Yao, Lei
Understanding the impact on the thermal effect by urbanization is of great significance for urban thermal regulation and is essential for determining the relationship between the urban heat island (UHI) effect and the complexities of urban function and landscape structure. For this purpose, we conducted case research in the metropolitan region of Beijing, China, and nearly 5000 urban blocks assigned different urban function zones (UFZs) were identified as the basic spatial analysis units. The seasonal land surface temperature (LST) retrieved from remote sensing data was used to represent the UHI characteristics of the study area, and the surface biophysical parameters, building forms, and filtered landscape pattern metrics were selected as the urban landscape factors. Then, the effects of urban function and landscape structure on the UHI effect were examined based on the optimal results of the ordinary least squares and geographically weighted regression models. The results indicated that (1) Significant spatiotemporal heterogeneity of the LST was found in the study area, and there was an obvious temperature gradient with “working–living–resting” UFZs. (2) All types of urban landscape factors showed a significant contribution to the seasonal LST, in the order of surface biophysical factors > building forms > landscape factors; however, their contributions varied in different seasons. (3) The major contributing factors showed a certain difference due to the variation of urban function and landscape complexity. This study expands the understanding on the complex relationship among urban landscape, function, and thermal environment, which could benefit urban landscape planning for UHI alleviation.
Mostrar más [+] Menos [-]Evaluation of sustainable groundwater utilization using index methods (WQI and IWQI), multivariate analysis, and GIS: the case of Akşehir District (Konya/Turkey) Texto completo
2021
Şener, Şehnaz | Varol, Simge | Şener, Erhan
Akşehir district is one of the regions where significant agricultural production and industrial activities are carried out. Groundwater is the most important water resource in this region used for different purposes, especially for drinking and irrigation water. In order to ensure sustainable water management in the study area, it is necessary to reveal the drinking and irrigation water quality of groundwater and to take precautions and determine the management plans. In the present study, groundwater quality was evaluated using water quality index methods (WQI and IWQI) and statistical analyses to determine the sustainable and most appropriate usage of groundwater. In addition, spatial distribution maps were prepared using GIS for drinking and irrigation WQI assessments of the groundwater. A total of 31 groundwater samples were collected from wells in October 2018 and physicochemical analysis results were evaluated. According to the results obtained with the WQI method, all groundwater samples in the study area are definitely not suitable for use as drinking water. According to the results obtained by the IWQI method, samples S23, S24, S25, S27, S28, S29, and S31 especially are not suitable for use as irrigation water. Statistical evaluations support the results obtained from WQI and IWQI methods. Also, factor analysis indicates that anthropogenic pollution, especially agricultural applications, is effective on the chemical and quality characteristics of groundwater samples in addition to the geological properties. As seen in the spatial distribution maps for WQI and IWQI results, while the quality of groundwaters around Doğruözü and Erdoğdu is not suitable for drinking water, the groundwater quality in the north-east of the study area is also unusable for irrigation water. Consequently, the use of groundwater in the region as drinking water can be dangerous for human health and alternative drinking water resources should be investigated. In addition, in order to ensure the sustainable use of groundwater, it is necessary to control agricultural activities in the region, to monitor the use of pesticides and fertilizers, and to encourage organic farming practices in the region.
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