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1.
A dense monitoring network is vital for the reliable assessment of PM10 in different parts of an urban area. In this study, a new idea is employed for the re-construction of the 20 shut-down PM10 monitoring stations of Berlin. It endeavours to find the non-linear relationship between the hourly PM10 concentration of both the still operating and the shut-down PM10 monitoring stations by using a fuzzy modelling technique, called modified active learning method (MALM). In addition, the simulations were performed by using not only raw PM10 databases but also log-transformed PM10 databases for skewness reduction. According to the results of hourly PM10 simulation (root mean square error about 13.0 μg/m3, correlation coefficient 0.88), the shut-down stations have been appropriately simulated and the idea of dense monitoring network development by the re-construction of the shut-down stations was realised. The results of simulations using raw and log-transformed databases showed that data transformation has no significant effect on the performance of MALM in the simulation of shut-down PM10 stations. By the combination of the 11 still operating stations and the 20 re-constructed stations, a dense monitoring network was generated for Berlin and was utilised for the calculation of the reliable monthly and mean annual PM10 concentration for five different PM10 zones in Berlin (the suburban-background, urban-background, urban-traffic, rural-background and suburban-traffic areas). The results showed that the mean annual concentration of PM10 at the five zones increased by about 13.0% in 2014 (26.3 μg/m3) in comparison with 2013 (23.3 μg/m3). Furthermore, the mean annual concentration of PM10 in the traffic lanes of the suburban (2013 25.0 μg/m3, 2014 26.9 μg/m3) and urban (2013 27.7 μg/m3, 2014 31.3 μg/m3) areas is about 14 and 20% higher than the PM10 concentration of suburban-background (2013 21.3 μg/m3, 2014 24.5 μg/m3) and urban-background (2013 23.0 μg/m3, 2014 26.1 μg/m3) areas, respectively.  相似文献   
2.
Environmental Science and Pollution Research - Drug resistance of cancer cells is a major issue in cancer treatment. Plant-mediated nanoparticle synthesis has been applied in recent years to...  相似文献   
3.
In this work we developed and optimized two molecular-based approaches to monitor rapidly, sensitively and specifically bacterial pathogens from three different genera, Escherichia coli, Pseudomonas aeruginosa, and Salmonella spp., directly in waters. To achieve this aim, firstly a multiplex-PCR assay (M-PCR) was optimized using a primer pair specific for each pathogen. Secondly, as a molecular confirmatory test after isolation of the pathogens by classical microbiological methods, PCR-RFLP of their amplified 16S rDNA genes was performed. It was observed from the results that the developed M-PCR assay has significant impact on the ability to detect sensitively, rapidly and specifically the three pathogens directly in water within a short time (5 h from sampling to obtain final results), therefore it represents a considerable advancement over other known more time-consuming and less-sensitive methods for identification and characterization of these kinds of pathogens.  相似文献   
4.
The aim of this study was to determine the influence of different levels of dissolved oxygen (DO) on embryonic development (ED) and hatching success of Greenland halibut (Reinhardtius hippoglossoides) eggs. Fertilized eggs from six females were exposed to five DO levels: severely hypoxic (10 and 20?%sat [percent saturation]), moderately hypoxic (35 and 50?%sat), and normoxic (100?%sat). Greenland halibut eggs were highly tolerant to hypoxia, with hatching occurring at levels as low as 20?%sat. In severely hypoxic conditions (10?%sat), ED was impaired and no hatching occurred. Lipid composition, during ED, changed as a function of female origin and DO levels. Phospholipids were the dominant lipid class in eggs. Although triacylglycerols were a minor lipid class in terms of abundance, they were only used under severe hypoxia. The results suggest that severe hypoxia (between 10 and 20?%sat) has detrimental effect on the early development of Greenland halibut and may result in reduced recruitment and lower population abundance if the decreasing trend in the DO levels observed in the bottom waters of the Gulf of St. Lawrence continues in the future. Other species that share similar life histories may also be at risk.  相似文献   
5.
The maintenance of natural and virgin ecosystems against an unnecessary influx of humans requires a modern and efficient model such as the carrying capacity model to optimize the management and development of ecotourism in these areas. The model is one of the key tools for conservation and sustainability of these areas. The present research attempts to formulate a framework for the ecotourism carrying capacity model for sustainable development of Karkheh protected area in Iran. The information was collected using a citation method as well as, interviews with experts, and visitors, and director of the region with 24 key indicators being regulated by field surveys and library studies. In this study, the network analysis process model, the Pressure-State-Response conceptual model, and Arc GIS10.5 software were used to determine the potential for the establishment of ecotourism performance in the scale of 1: 50,000. In this research, 70 questionnaires were completed by experts in the field of environment and ecotourism to determine the relative importance of effective pressures. According to the results, the highest values belonged to physical carrying capacity (13,425,681 persons per day), ecological carrying capacity (2,482,226 persons per day), and social and culture (985,706 people per day), respectively. Based on the regional carrying capacity, the physical, ecological, and social carrying capacity index was calculated as 3356, 621, and 246 (greater than one), respectively. According to the results, the region has a high carrying capacity, which can accept visitors.  相似文献   
6.
Environmental Science and Pollution Research - This research aimed to investigate the effect of nanorice husk ash (NRHA) prepared using different thermal treatment methods on ultra-high-performance...  相似文献   
7.
Actinomycetes in rice straw decomposition   总被引:1,自引:0,他引:1  
Actinomycetes are well known as lignocellulose decomposers. Forty-two cellulolytic actinomycete isolates have been recovered from soil. Those were identified to the genus level as: Streptomyces (26 isolates), Nocardiopsis (5 isolates), Micromonospora (4 isolates), Nocardioides (4 isolates) in addition to three isolates tentatively identified as Nocardia, Kibdelosporangium and Saccharomonospora. These actinomycetes were examined for their cellulolytic activity using filter paper strips and rice straw pieces. Four isolates of the four genera Kibdelosporangium, Micromonospora, Streptomyces and Nocardioides were able to efficiently degrade rice straw pieces in minimal medium causing significant weight loss between 50 and 61%. Application of this knowledge may improve the management of waste rice straw.  相似文献   
8.
The lakes’ fisheries play an important role in Egyptian economy. In 1980s, they provided more than 50 % of harvested fish in Egypt but now their contribution to the Egypt fish production decreased to only 12.5 % in 2012. Lake Timsah, one of the Suez Canal lakes, faced many challenges that lead to serious changes in its water and fish quality, fish production, as well as the catch composition. The present work investigated the impact of pollution, food availability, and excessive fishing mortality on the haffara production in lake Timsah. The distribution of four heavy metals (Pb, Zn, Ni, and Fe) was detected seasonally in water and in muscles, gills, and livers of Rhabdosargus haffara, during 2012 through 2013. Fe and Zn were presented by high values in liver, while Pb and Ni in gills. Generally, the lowest concentrations of all metals were found in muscles. The recorded crustacean organisms (the main food of haffara) decreased from 12 species and 32,079 organisms?m2 in 2012 to only 7 species and 7290 organisms?m2 in 2013 while the amphipods completely disappeared. This serious change was due to the severe pollution in the lake. A logistic surplus production model was fitted to the catch per unit effort indices, to estimate the maximum sustainable yield and the optimum level of fishing effort. The results revealed that haffara stock at lake Timsah is overfished, and the estimated precautionary target reference points advised the reduction of fishing effort by about 30–50 %.  相似文献   
9.
10.
Environmental Science and Pollution Research - In this study, the effects of adding a condensing cavity in a passive single-basin solar still are investigated experimentally under the climate...  相似文献   
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