Chitosan is one of the natural biopolymer. Despite its importance, the characterization and extraction processes of this essential biopolymer are yet enigmatic. In this study, we developed an analytical procedure for the extraction of chitin and chitosan from the aquatic beetles’ shells (Hydraenidae family). The commercial chitosan and isolated chitosan, obtained during our experiment were analyzed by XRD, EDX, SEM, FT-IR, TGA, and UV-vis DRS techniques. Our results indicate 38% chitin and 23.5% chitosan segregated from the aquatic beetles’ shells. The ratio of protein residues to the wet weight (RWW) of the segregated chitosan was about 24%. FT-IR analysis attested that the isolated chitosan from the aquatic beetles’ shells was identical to the commercial chitosan. The EDX analysis does not reveal any impurities or the used precursor's characterized peaks, confirming high purity percentage of the segregated chitosan. Furthermore, according to the SEM images the segregated chitosan has smooth surface with amorphous property. Ultimately, the antibacterial activities of isolated chitosan were investigated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria to assess their potential antibacterial applications. The results showed that the isolated chitosan from the aquatic beetles represented an outstanding performance in against the studied bacteria. پرونده مقاله

AbstractThe use of chemical fertilizers in agricultural sector leads to increase of nitrate concentrations in surface and groundwater. The present study determined the vast impacts of agriculture in Ardabil Plain in the northwest of Iran. The study surveyed and measured the amount of nitrate concentration in groundwater sources of 46 wells in the region. Arc GIS software was used to zoning of the area by ordinary kriging function. To match the changes of nitrate concentrations with the land use patterns, images of Landsat Satellite ETM+ in June of 2012 was applied. To determine the relationship of agricultural land use with nitrate distribution in the area SPSS 16 software was used. According to the regression results, the use of agricultural land use and the amount of chemical fertilizer in the region are highly related with nitrate distribution with 95% accuracy. The results showed that the source of nitrate input to the region is the use of artificial nitrate fertilizer in agricultural activities. پرونده مقاله

Coastal areas are of the most important natural ecosystems around the world, continuously influenced by various human activities, in particular tourism development leading to instability in some coastal areas. The coastal areas of Gilan province in Iran as an important tourist destination have been attracting always special attention of many tourists, investors and operators of tourism. Given the need for the environmental protection regarding the coastal tourism development, the present descriptive-analytical study aimed to identify coastal tourism potentials in the Gilan province by analyzing satellite images and field surveys and provide relevant promotional strategies through SWOT analysis. The results revealed that a majority of coastal areas had developmental constraints, and only one-third of these coasts, including Amirkalaye and Talesh, had the tourism development potential. Moreover, total score of internal factors calculated less than 2.5 (i.e., 2.11) highlighted a relative weakness for the coasts of Gilan province in terms of tourism capabilities. The results of the SWOT analysis also showed that the coastal tourism in this region was in a defensive state environmentally. In conclusion, the factors affecting coastal tourism development based on our developed SWOT matrix were found to be domestic and foreign investments, administrative coordination, detection of coastal capacity, tourism development and environmental tourism planning. پرونده مقاله

In this study systematic random sampling was conducted. To estimate the sample size, 100 households were selected based on the population of the city using Cochran's formula. Total generated municipal solid waste was consecutively collected, weighed and separated during a week. Then, after providing the required training through face-to-face manner and brochures regarding the economic, social, cultural and environmental importance of source separation to each of the households, once again the generated wastes were collected, weighed and separated. The difference in the composition and amount of waste generated before and after the training was compared by independent t-test. The effect of the demographic characteristics of the head of the household on reducing the amount of generated waste was determined by correlation test. The results highlighted the training as an effective intervention on the weight of produced waste from each household before and after the training (P=0.000). Education increases people's awareness about waste, recycling, harms of waste, definition of separation, benefits of separation, source separation and level of household education. The reduction in the amount of produced waste had no significant correlation with the age (P=0.89), occupation (P=0.16), income (P=0.95) and education level (P=0.36) of the heads of each household. The findings of this research showed that education, regardless of demographic characteristics, is an effective method to change specific behavior and create motivation to reduce the amount of waste at source, underlining the importance of training to improve waste recycling management. پرونده مقاله