Salimi P.,Islamic Azad University at Astara |
Karapinar E.,Atilim University
Mathematical Problems in Engineering | Year: 2013
We prove the existence and uniqueness of a fixed point of certain type mapping, extension of Suzuki-Edelstein mapping, in a partially ordered complete metric space. Our results extend, improve, and generalize the existence results on the topic in the literature. We state some examples to illustrate our results. © 2013 Peyman Salimi and Erdal Karapinar.
Taghizadeh R.,Islamic Azad University at Astara |
Sharifi R.S.,University of Mohaghegh
Journal of Food, Agriculture and Environment | Year: 2010
In order to study the effects of post-anthesis heat stress on yield and yield attributes in wheat (T. aestivum) genotypes, a factorial experiment based on randomized complete block design with three replications was conducted in 2008 at the Research Farm of Islamic Azad University, Ardabil Branch. Treatments were post-anthesis heat stress with change of planting dates in three levels (2 October,17 October and 1 November) plus wheat genotypes in four levels (Sardari, Finkan, Saisonez and Azar). Results indicated that different levels of post-anthesis heat stress had significant effects on yield and yield components in wheat genotypes. Wheat genotypes had different response to these characteristics. The grain yield varied between 226 g m-2 in Sardari genotype and 115 g m-2 in Saisonez genotype. Combined effect of genotypexdifferent levels of post-anthesis heat stress was significant on grain yield. Maximum grain yield (229 g m-2) was obtained in the plots where Sardari genotype was planted in the first sowing date and minimum of it (115.5 g m-2) was obtained in the plots where Saisonez genotype was planted in the third sowing date due to confronting with increasing in post-anthesis heat stress. In conclusion, it can be suggested that in order to increase grain yield, Sardari genotype should be planted in the first sowing date due to the least period of confronting with post-anthesis heat stress in conditions of Ardabil Plain.
Nozari O.,Islamic Azad University at Astara |
Madanipour M.,Islamic Azad University at Astara |
Farsi M.,Islamic Azad University at Sari |
Tabei A.,Islamic Azad University at Astara
Cellulose Chemistry and Technology | Year: 2013
The purpose of this study is to evaluate the effect of nanoclay and alkali treatment of wood flour on the engineering properties of the wood plastic composite made from low-density polyethylene (LDPE) and beech flour. Thus, to conduct the study, the wood flour was chemically treated with 2% alkaline and then was mixed with LDPE at 40% weight ratio. To improve the properties of the composites, nanoclay particles (Cloisite 15 A) with the weight percentage of 0, 3 and 6% were selected for the study. In all samples, maleic anhydride grafted polyethylene (MAPE) was used in a weight proportion of 3%. The materials were mixed in an internal mixer (HAAKE) and then the samples were made using an injecting molding instrument. The physical properties, such as water absorption, and mechanical properties, such as tensile and impact strength, were measured. The physical testing results showed that by increasing the nanoclay content and alkaline treatment application, the water absorption rate was reduced. The tensile strength improved by increasing the nanoclay content, as well as using the chemical treatments. Also, the impact strength witnessed a 3% increase by increasing the nanoclay content and then reduced. The overall results suggest that the chemical treatments will increase the impact strength.
Eghbal M.Z.K.,Islamic Azad University at Astara
Earth Sciences Research Journal | Year: 2014
The aim of this research was to study of sediment pollution conditions in the river bed of Khajeh Kory, which passes from the southern border of the Caspian Sea in Astara City. To determine the pollution of river bed sediment along the route, from the river source in the heights to estuary in the Caspian sea, sampling was conducted at 10 stations. Afterward, each sample was divided into two groups based on size (>63 μm and <63 μm). The concentration of heavy metals Cu, Cd, Co, Zn, Pb, Ni, Fe, and Mn in each group was measured using ICP-OES. In the next stage, the enrichment of samples was determined by normalization with aluminum. The data were then interpolated using the Kriging method and various models (including spherical, circular, exponential, Gaussian) were fitted to the data, and the best method was selected using the Cross Validation method. Using the obtained enrichment outcomes, an information layer was produced for each element in the GIS environment utilizing the Kriging method. The layers were aggregated and the compiled layer was classified into 4 layers again. Using this method, the length of the river from its source to the sea estuary was characterized based on the contamination of heavy metals, and contaminated and unpolluted areas in river sediments could be observed. The source of this pollution, either natural or manmade, was revealed through this method. © 2014, Universidad Nacional de Colombia. All Rights Reserved.
Babaei I.,Islamic Azad University at Astara |
Madanipour M.,Islamic Azad University at Astara |
Farsi M.,Islamic Azad University at Sari |
Farajpoor A.,Islamic Azad University at Astara
Composites Part B: Engineering | Year: 2014
In this study, the effects of Azodicarbonamide (AZD) and nanoclay (NC) content on the physico-mechanical and foaming properties of HDPE/wheat straw flour (WSF) composites were investigated. To meet this objective, AZD as the exothermic chemical foaming agent (CFA) with 3 levels of 0, 2 and 4 phr (per hundred parts of resin) and three NC levels of 0, 2, and 5 phr were used. The amount of WSF was fixed at 40 phr for all formulations. First, the WSF, HPDE, NC and AZD were compounded under the foaming agent decomposing temperature in an internal mixer (HAAKE) and microcellular closed cell foamed samples were prepared using an injection molding machine in a batch foaming process. The cellular structure results showed that by increasing the AZD content from 2 to 4 phr, the average cell size and cell density increased whereas the foam density showed a decrease to 21.7% and by adding NC up to 5 phr, the cell size decreased and the cell density increased. When the contents of the AZD increased from 0 to 4 phr, the water absorption and thickness swelling of samples increased to 19.3% and 26.5% respectively. The mechanical properties of HPDE/WSF composite were reduced by adding the CFA and it was improved by adding 2 phr of NC. It should also be noted that the addition of AZD and NC had a negative effect on the foamed composites impact resistance. These results were further supported by SEM micrographs. © 2013 Elsevier Ltd. All rights reserved.
Pirdel L.,Islamic Azad University at Ardabil |
Pirdel M.,Islamic Azad University at Astara
Reproduction | Year: 2014
This article presents an overview of the involvement of iron overload-induced nitric oxide (NO) overproduction in apoptosis of peritoneal macrophages of women with endometriosis. We have postulated that the peritoneal iron overload originated from retrograde menstruation or bleeding lesions in the ectopic endometrium, which may contribute to the development of endometriosis by a wide range of mechanisms, including oxidative damage and chronic inflammation. Excessive NO production may also be associated with impaired clearance of endometrial cells by macrophages, which promotes cell growth in the peritoneal cavity. Therefore, further research of the mechanisms and consequences of macrophage apoptosis in endometriosis helps discover novel therapeutic strategies that are designed to prevent progression of endometriosis. © 2014 Society for Reproduction and Fertility.
Liany Y.,Islamic Azad University at Astara |
Tabei A.,Islamic Azad University at Astara |
Farsi M.,Islamic Azad University at Sari |
Madanipour M.,Islamic Azad University at Astara
Fibers and Polymers | Year: 2013
Since natural fiber/polymer composites are increasingly used, the development of safe and environmental friendly flame retarding bio-based composites is of great importance. But this issue must maintain the mechanical performance of these composites. To study these objectives, four levels of magnesium hydroxide Mg(OH)2 of (0, 10, 20, 30 phc) and two levels of nanoclay (0, 3 phc) were considered and incorporated into HDPE/wheat straw composites. Maleic anhydride grafted polyethylene (PE-g-MA) was also used as a compatibilizer at constant content. The samples were prepared by melt compounding and injection molding processes, respectively. The some properties of samples including burning rate and mechanical properties (tensile and impact strengths) were tested based on the ASTM standard. The results showed that the burning rate of samples decreased with increasing the nanoclay and Mg(OH)2 content. The tensile and impact strengths showed a marginal reduction by adding Mg(OH)2 from 10 phc to 30 phc and the tensile modulus and impact strength revealed an increase by increasing the amount of nanoclay up to 3 phc. Generally, these results confirmed that the fire retarding and mechanical properties of HDPE/wheat straw composites could be significantly improved with an appropriate combination of the nanoclay and Mg(OH)2 in the composites. © 2013 The Korean Fiber Society and Springer Science+Business Media Dordrecht.
Atashi A.,Islamic Azad University at Astara |
Abdolpour R.,Islamic Azad University at Astara
Life Science Journal | Year: 2012
Small and risk able companies are remarkably skilled at identifying entrepreneurship opportunities. Upon arrival, these new companies encounter high environmental uncertainty. This turbulence can quickly lead to disintegration of these companies because of being barely effective in development and maintenance of competitive advantages needed for benefiting from these opportunities by the course of time. Besides establishment of company, the entrepreneurs can be hopeful to their long-term survival only if their resources are strategically utilized. Objective of strategic entrepreneurship attitude is to organize the resources so as to help identification and utilization of entrepreneurial opportunities contributing to development of competitive advantage. Among others, human resource is highly significant due to its scarcity, non-substitutability and non- limitability.In the current paper, significance of strategic entrepreneurship as an opportunity and strategic human resources management as the most important competitive advantage was comprehensively studied in wealth production for fledging companies.
Hosseinjani N.,Islamic Azad University at Astara
Advances in Environmental Biology | Year: 2014
Cold formed structural system is a light steel frame (Lightweight Steel Framing) System that is briefly called LSF. This method is a good alternative to traditional methods. Wall voids are stuffed with insulating material such as glass wool and rock wool. In this study, constructs cold formed inside walls are filled with lightweight concrete and seismic behavior. It is analyzed that use of concrete in structures, cold formed filler walls increase peripheral resistance, decreased structure and increased general shift towards structural plasticity is hollow structures with walls. © 2014 AENSI Publisher All rights reserved.
Ghazba F.,University of Tehran |
Zare Khosh Eghbal M.,Islamic Azad University at Astara
Journal of Environmental Studies | Year: 2011
Introduction Anzali wetland is a vast lowland catchment area with autotrophic fresh water, located in the south-west of the Caspian Sea. One of the major functions of this wetland is the sediment entrapment and associated pollutions including pollution by heavy metals of the aquatic ecosystems. Heavy metals have a tendency to accumulate in the bottom sediments, and their determination in sediments could provide valuable information concerning their source, distribution and the degree and rate of pollution in the area. This wetland with an area about 193km2 is located in northern Iran, in Gilan province. Its average length along east-west direction is about 30km while its average width along north-south is about 3km. On the basis of its physical, chemical, morphological and ecological characteristics, the wetland is divided into four main parts. The Pasikhan River is the principal river which enters the central part or Hendekhale. The western part of the wetland called Abkenar is the deepest part with Chafroud River entering it. The protected part of the wetland is called Siakishom that receives a large volume of water from rivers. The wetland is connected to the waters of the ar-e-Anzali (fig 1) by a 3.5 km shipping canal. Different types of igneous, sedimentary and metamorphic rocks ranging in the age of Paleozoic to Recent are cropping out in the region. They contain different minerals and these rocks are covering the entire basin and the wetland. The presence of the metallic minerals and their oxidation processes appears to have caused the natural enrichment of heavy metals such as Cd and As in the local river sediments and soils. FIFURE PRESENTED The urban development and urbanization is very intense from west to east of the wetland while there is considerable agricultural and stockbreeding activities from east to west of the wetland. Materials and methods The sediment samples used in this research were collected in the spring of 1387. Seven sampling stations (see fig. 1) were selected in different parts of the wetland. Sediment cores were collected in these stations, using 5 centimeters diameter PVC pipes which were inserted in the bottom sediments (fig. 2). FIGURE PRESENTED In order to determine the sedimentary characteristics of the sediments in the cores, granulometry and XRD analysis was performed. The concentrations of the major elements including Al, Ca, Fe, Mg, Na, Ca, Mn, P, Ti and trace elements including Li, Ba, S, Sr, As, Cd, Cr, Co, Cu, Mo, Ni, Pb, V, Zn, Bi at different depths were determined using inductively coupled plasma mass spectrometry (ICP-MS) in the laboratory of AlsChemex Company. The detection limits are presented in table-1. TABLE PRESENTED Discussion of Results Following the concentrations determination of different elements, Pearson correlation coefficients were performed in order to assess the statistical relationships and furthermore, to determine the source of heavy metals incorporated into the sediments. The software SPSS 16 was also used in all of the analyses. High correlations between Cr, Ni, Zn and Co with Fe, Al, in the Abkenar region indicates their natural source. While in Siahkishom area, elements such as Fe, Be, K, Zn, Bi, Ba, Zn and V, show high correlations with Al, are related to the terrestrial source. In addition, the positively high correlation between P and Ca and Na could indicate the fact that these elements are supplied to the sediments by heavy use of detergents. In this part of the wetland, Bi, V, Zn and Pb display high correlations with Al and Fe and as a result, it is concluded that they are sourced from the rocks covering the entire basin while other trace elements have anthropogenic source. In the Hendekhale area, the high correlations of Al with Fe, Ti, Mg, Cu, and Ni could suggest geogenic sources. Cadmium showing high correlation with Barium may well indicate their deposition in the wetland by the counter clockwise water circulation from the Caspian Sea coming from the oil wells and petroleum drilling operations in Azarbijan area. However such an assessment warrants further investigations. The other reason for high Cd concentration is the wearing down of the tires via roads into the Hendekhale area. The local road maps show that there are several roads in the area. The input of Cd and Zn from the transportation network and roads could be substantial. In the Shijan region, the high correlation of Al with Fe, K and Mg is a strong indicator of their natural geogenic sources. The concentrations of Bi, Cd, Cr and Zn in the surface sediments of the wetland except for Abkenar area, show high concentrations, while other elements including Co, Cu, Ni, Mo and V show values close to the natural backgrounds. The pollution source(s) is mainly located on the eastern parts of the wetland when the data are compared to the information obtained from the west. Conclusions Based on the geochemical results obtained here, it is clear that the concentrations of most of the heavy metals in the sediments of Anzali wetland is higher than the values reported from the sediments in Caspian Sea and their global average. Therefore, monitoring the concentrations of the heavy metals and other pollutant is of vital importance and must be done on a regular basis. One of the most effective methods in reducing the accumulation of heavy metals in the sediments of the wetland appears to be the self-refining ability in preventing further pollution of the aquatic system of the wetland's fragile environment. However, the ability of the wetland to refine itself could be very limited because of high rate of incoming pollutants. In addition, this aquatic ecosystem with one of its functions as a sediment trap operates as a protection against absorbing the pollutants from land sources (i.e., industrial, agricultural and domestic sources) and prevents them from entering the Caspian Sea. Considering all sources of heavy metals pollutions with their ever increasing rate of production and input to the wetland, it is vital to protect such an important and fragile environment.