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The current study assessed the effects of common herbicides produced by different companies on broadleaved and grass weed control and quantitative traits of irrigated wheat. A two-year experiment (2013-2014 and 2014-2015) was designed as an RCBD with three replications. Experimental treatments included two control treatments (weedy and weed-free) and 15 herbicides produced by three Iranian companies (Ghazal, Golsam-Gorgan, and Gyah) and three international companies (BASF, Nufarm, and Syngenta). The results showed that H13 (bromoxynil + MCPA from BASF tank-mixed with clodinafop propargyl from Golsam Gorgan) and H14 (bromoxynil + MCPA from BASF tank mixed with clodinafop propargyl from Ghazal) treatments in 2014 and H5 (tribenuron methyl from Gyah) and H9 (clodinafop propargyl tank-mixed with tribenuron methyl from Golsam Gorgan) in 2015 almost completely controlled broadleaved and grass weeds. In 2014, H4 (2,4-D + MCPA from Nufarm) and H13 treatments with the averages of 7505 and 7338 kg ha^-1 ranked first and second in grain yield, while H9 and H12 (bromoxynil + MCPA from BASF tank-mixed with clodinafop propargyl from Gyah) with the averages of 7966 and 7917 kg ha^-1 were known as superior treatments in 2015. Averaged by years, the grain yield was 3185 kg ha^-1 at weedy treatment (H17). Although there were no significant differences between herbicides, the grain yield (averaged by years and herbicides) was boosted by 88% compared with the weedy treatment. It was concluded that more rainfall and desirable air temperature positively affected the efficacy of the herbicides.
 

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Due to the increasing demand for using polyethylene pipes in gas distribution networks and regarding the technical specifications of transmission and suitable service condition as well as ease of implementation and installation, these materials are considered as ideal substitutes for metal pipes. Regarding the safety and economic aspects in PE (polyethylene) pipe networks before and during the operations, technical inspection is highly required. Examinations have a significant role in the safety and proper function of gas distribution PE pipes tests, because of the damage of the products and excessive costs and time are not usually affordable. Consequently, the mentioned tests are nowadays being replaced by non-destructive types and admissibility of various industries gas company in these methods is increasing. Electrofusion is a proper and fundamental technique for connecting PE pipes. In this research, the mechanism of electrofusion tapping saddle polyethylene welding has thoroughly been studied and simulated using ABAQUS software. Thermal equation of electrofusion is investigated and the results of simulation as compared with experimental results have been evaluated based on which the best qualified methods for connection have been determined and presented.

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 In recent years, the development of a knowledge-based economy and the presence of Iranian companies in global markets has become one of the main economic priorities of the country. The purpose of this study is to develop and develop a strategic model for the transnational presence of knowledge-based companies in foreign markets in a mixed exploratory study. After identifying the knowledge-based companies’ internationalization constructs in a qualitative study in this research, by interviewing 14 connoisseurs and analyzing the data that acquired from the interviews using the grounded theory method, in a quantitative study and collecting information through a questionnaire of 243 in 73 company, the partial least squares approach to structural equation modeling has been used to estimate and calculate the relationships in the achieved model. Analysis of research data shows that the combination of three categories of resource-oriented, network-oriented, and entrepreneur-oriented components can lead to the sustainable international presence of Iranian knowledge-based companies. And their strategy is to grow through a customer-oriented competition based on technology, and they can get improved performance in three components: reputation, survival, and technological growth.