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1.
Environmental Science and Pollution Research - The effects of diazinon (DZN), an organophosphate pesticide, on lipid profiles have been extensively reported. However, controversy on this issue...  相似文献   
2.
To date, several methods have been proposed to explain the complex process of air pollution prediction. One of these methods uses neural networks. Artificial neural networks (ANN) are a branch of artificial intelligence, and because of their nonlinear mathematical structures and ability to provide acceptable forecasts, they have gained popularity among researchers. The goal of our study as documented in this article was to compare the abilities of two different ANNs, the multilayer perceptron (MLP) and radial basis function (RBF) neural networks, to predict carbon monoxide (CO) concentrations in the air of Pardis City, Iran. For the study, we used data collected hourly on temperature, wind speed, and humidity as inputs to train the networks. The MLP neural network had two hidden layers that contained 13 neurons in the first layer and 25 neurons in the second layer and reached a mean bias error (MBE) of 0.06. The coefficient of determination (R2), index of agreement (IA), and the Nash–Scutcliffe efficiency (E) between the observed and predicted data using the MLP neural network were 0.96, 0.9057, and 0.957, respectively. The RBF neural network with a hidden layer containing 130 neurons reached an MBE of 0.04. The R2, IA, and E between the observed and predicted data using the RBF neural network were 0.981, 0.954, and 0.979, respectively. The results provided by the RBF neural network had greater acceptable accuracy than was the case with the MLP neural network. Finally, the results of a sensitivity analysis using the MLP neural network indicated that temperature is the primary factor in the prediction of CO concentrations and that wind speed and humidity are factors of second and third importance when forecasting CO levels.  相似文献   
3.
In recent years, interest has grown in the potential to utilize more natural materials in the food industry. Shrimp waste is an important natural resource with functional properties and no known side effects. The major components of shrimp waste are protein, chitin, minerals and carotenoids. In the present study, the extraction of carotenoids was performed with two methods, the use of proteolytic enzymes and extraction by alkaline and enzyme treatment, and the total amount of carotenoids present in the waste was determined. Furthermore, the effectiveness of the method was evaluated through the inhibition of lipid peroxidation. Inhibition of lipid peroxidation was effectively done with carotenoid extracted by trypsin and alkaline treatment.  相似文献   
4.
Natural zeolites     
Zeolites, a suite of porous, fine-grained minerals commonly found in certain near-surface, sedimentary rocks, have special physical and chemical properties that could make them valuable to farmers in developing countries. Zeolites have been used to improve soil fertility; develop slow-release fertilizers; improve animal waste disposal; and improve animal health. To date most research on zeolite deposits and their various applications has been undertaken by the industrialized nations. Some zeolite deposits, however, also exist in developing countries and the likelihood of the existence of additional deposits in those countries is high. However, thorough assessment of the mineralogy, geology, and various agricultural uses is still needed. Strengthening developing countries' geological surveys in non-metallic mineral exploration and assessment will improve the likelihood that the use of zeolites will reach their full potential in developing country agriculture.  相似文献   
5.
Environmental Science and Pollution Research - The gill tissue is the main site of metabolic enzymes or compensation, with the kidney tissue playing a supporting role. At the gill tissue, carbonic...  相似文献   
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7.
The aims of the present study were to investigate the metal contents of sediments of several creeks that discharged into coastal waters using the Risk index. This study was carried out in eight creeks in Mahshahr coastal waters in the Northwest of Persian Gulf from October 2005 to November 2006. Superficial sediments were collected seasonally by Peterson grab, and the concentrations of heavy metals were measured by using a voltammetric polarographic method. The range and the mean concentrations obtained in ppm were 15.03–35.16 (27.01) for Cu, 65.57–171.41 (102.67) for Ni, 4.63–20.06 (13.22) for Co, 0.093–0.78 (0.22) for Hg, 65.07–379 (113.70) for Zn, 0.27–1.00 (0.56) for Cd and 7.09–29.72 (14.66) for Pb. To evaluate the levels of sediment contamination, the background values of the different heavy metals were calculated, and the contamination factor for each metal and the degree of contamination for each creek were determined as well. The results show that some elements such as Hg, Zn, and Ni are at risk level, and all of the studied creeks are classified as undergoing a moderate degree of pollution except for Ghannam that showed a considerable degree of contamination. According to the Risk index values, based on sedimentological toxic factors (St) of each metal and the BIO Production Index (BPI) in the studied area, the creeks were classified as considerable and with a very high level of ecological risk.  相似文献   
8.
Green spaces considered natural remnants in urban environments play a key role in promoting environmental quality and forming a sustainable city. Nowadays, development of urban spaces has taken a hasty growth. In the meanwhile, the natural green spaces are severely damaged. The current study aims at investigating the trend of changes in green space of Tabriz City, the second large industrial city in Iran, on the basis of landscape ecology principles. In order to prepare the land-cover maps, Landsat TM and IRS LISS-III of the years 1989 and 2006 were applied. Alongside, landscape percentage metrics, the largest patch index, number of patches, patch density, edge density, total edge, class area and landscape shape index were also used to analyse the changes. Metric analysis of the landscape within the studied years revealed that a large part of the region has enjoyed a rapid growth (equivalent to 64.5 %) in constructions. As the obtained results showed, the smallest landscape percentage (3.9 %) in the study area is belonged to the municipal green space, while the largest landscape percentage (66 %) is allocated to the barren land. This shows that the constructions have not balanced with creation of new green spaces, and the lack of green space per capita continues to be felt.  相似文献   
9.
Measures taken to cope with the possible effects of climate change on water resources management are key for the successful adaptation to such change. This work assesses the environmental water demand of the Karkheh river in the reach comprising Karkheh dam to the Hoor-al-Azim wetland, Iran, under climate change during the period 2010–2059. The assessment of the environmental demand applies (1) representative concentration pathways (RCPs) and (2) downscaling methods. The first phase of this work projects temperature and rainfall in the period 2010–2059 under three RCPs and with two downscaling methods. Thus, six climatic scenarios are generated. The results showed that temperature and rainfall average would increase in the range of 1.7–5.2 and 1.9–9.2%, respectively. Subsequently, flows corresponding to the six different climatic scenarios are simulated with the unit hydrographs and component flows from rainfall, evaporation, and stream flow data (IHACRES) rainfall-runoff model and are input to the Karkheh reservoir. The simulation results indicated increases of 0.9–7.7% in the average flow under the six simulation scenarios during the period of analysis. The second phase of this paper’s methodology determines the monthly minimum environmental water demands of the Karkheh river associated with the six simulation scenarios using a hydrological method. The determined environmental demands are compared with historical ones. The results show that the temporal variation of monthly environmental demand would change under climate change conditions. Furthermore, some climatic scenarios project environmental water demand larger than and some of them project less than the baseline one.  相似文献   
10.
Certain plants have demonstrated the capability to take up and accumulate metals, thus offering the potential to remediate metal-contaminated water and sediment. Several aquatic species have further been identified which can take up metal and metal oxide engineered nanoparticles (ENPs). It is important to evaluate if aquatic plants exhibiting potential for metal phytoremediation can be applied to remediation of metallic ENPs. Understanding the interactions between ENPs and aquatic plants, and evaluating possible influences on metal uptake and phytoremediation processes is therefore essential. This review article will address the feasibility of green plants for treatment of ENP-affected aquatic ecosystems. Discussion will include common types of ENPs in current use; transformations of ENPs in aquatic systems; the importance of microorganisms in supporting plant growth; ENP entry into the plant; the influence of microorganisms in promoting plant uptake; and recent findings in phytoremediation of ENP-affected water, including applications to constructed wetlands.  相似文献   
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