Islamic Azad University North Tehran Branch

About: Islamic Azad University North Tehran Branch is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Adsorption & Catalysis. The organization has 868 authors who have published 968 publications receiving 9987 citations.

Investigating peak stresses in fitting and repair patches of buried polyethylene gas pipes

Abstract: Nowadays, polyethylene composes a large number of natural gas distribution pipelines installed under the ground. The focus of the present contribution is two fold. One of the objectives is to investigate the applicability of polyethylene fittings in joining polyethylene gas pipes which are electrofused onto the pipe ends and buried under the ground, by estimating stress distribution using finite element method. The second objective is to study the effectiveness of polyethylene repair patches which are used to mend the defected pipelines by performing a finite element analysis to calculate peak stress values. Buried polyethylene pipelines in the natural gas industry, can be imposed by sever loadings including the soil-structure interaction, traffic load, soil’s column weight, internal pressure, and thermal loads resulting from daily and/or seasonal temperature changes. Additionally, due to the application of pipe joints, and repair patches local stresses superimposed on the aforementioned loading effects. The pipe is assumed to be made of PE80 resin and its jointing socket, and the repair patch is PE100 material. The computational analysis of stresses and the computer simulations are performed using ANSYS commercial software. According to the results, the peak stress values take place in the middle of the fitting and at its internal surface. The maximum stress values in fitting and pipe are below the allowable stresses which shows the proper use of introduced fitting is applicable even in hot climate areas of Ahvaz, Iran. Although the buried pipe is imposed to the maximum values of stresses, the PE100 socket is more sensitive to a temperature drop. Furthermore, all four studied patch arrangements show significant reinforcing effects on the defected section of the buried PE gas pipe to transfer applied loads. Meanwhile, the defected buried medium density polyethylene gas pipe and its saddle fused patch can resist the imposed mechanical and thermal loads of 22°C temperature increase. Moreover, increasing the saddle fusion patch length to 12 inches reduces the maximum stress values in the pipe, significantly.

Comparison of Physicochemical Characteristics of Margarine and Butter in Iranian Market During Storage

Abstract: Margarine contains a higher level of unsaturated and trans-fatty acids (TFA) than butter. The aim of this study was to investigate the physicochemical properties of these products in Iranian market during storage. Physicochemical analyses included fatty acid composition, peroxide and Anisidine values, slip melting point (SMP), color, chlorophyll content, solid fat content (SFC) and texture analysis. Margarine, compared to the butter, contained a higher degree of unsaturation, TFA, SMP, peroxide and Anisidine than butter. Predominant TFA in butter and margarine were vaccenic (about 2.83-3.41%) and elaidic acids (about 7.55-9.26%), respectively. Peroxide and Anisidine values of margarine increased significantly during storage. a* value and SMP of all samples increased significantly during storage. The SMP of margarine-2 was more than that of other samples. Chlorophyll content of butter was significantly more than margarine. Also, the content of chlorophyll of all samples was constant during storage. L* and b* values of all samples decreased significantly during storage. SFC of butter was significantly (p<0.05) more than margarine at 5 to 10°C, but at temperatures ranging 20 to 35.5°C, SFC of margarine-2 was more than butter and margarine-1. At 5°C, a yield value of butter was significantly more than margarine-2, but at 20 and 30°C, a yield value of margarine-2 was more than butter and margarine-1. As a result, the comparison between butter and margarine showed that butter is superior in terms of qualitative factors. However, if the hydrogenation process in the manufacturing of margarine is removed and replaced by other safe methods it can lead to products with high nutritional value.

Investigating causal linkages and strategic mapping in the balanced scorecard: A case study approach in the banking industry sector

Abstract: One of the main challenges of strategic management is implementing the strategies. Designing the strategy map in Balanced Scorecard framework to determine the causality between strategic objectives is one of the most important issues in implementing the strategies. In designing the strategy map with intuition and judgment, the link between strategic objectives is not clear and it is not obvious which strategic objectives are related and influenced each other. Hence, it is essential to offer a quantitative and accurate method to design the strategy map and clarify these relationships. In this paper, after reviewing the methods for determining the causal relationships among BSC perspectives in the literature, a framework on the basis of historical data analysis and multi-response surface regression analysis is offered to determine causal relationships among strategic objectives with respect to data of key performance measures of past years in order to obtain the coefficients and equations that can be used in the prediction of the responses. Using statistically significant models, the correlations between the factors and several responses were acquired. The presented quantitative approach is useful for determining the causal relationships resulting in an accurate strategy map and is a supporting approach for improving decision makers’ opinions and enabling them to reach a more accurate picture of the relationships. This research also presents a case study to demonstrate the applicability of the proposed approach. The application and implication of the proposed method in a real case show that the contributions of the research are not only theoretical but practical as well. The strategy map constructed in this study can also serve as a reference point for similar businesses.

Bis(2,4,6-trimethyl-pyridinium) hexa-chloridoplatinate(IV).

Abstract: The asymmetric unit of the title compound, (C8H12N)2[PtCl6], contains one independent protonated 2,4,6-trimethyl­pyridinium cation and one half of a centrosymmetric [PtCl6]2− anion. The Pt ion has an almost ideal octa­hedral coordination. In the crystal structure, intra­molecular N—H⋯Cl and inter­molecular C—H⋯Cl hydrogen bonds result in the formation of a supra­molecular structure.