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Microstructure and mechanical properties development of X80 weld metal by addition of different amounts of alloying elements such as Nickel and Manganese to the covering of electrodes were investigated. For this reason samples were welded with electrodes that Ni value changed between 0.8%- 3.5% in tow critical amounts of Mn: 0.7 and 1.6. Tensile test and microhardness results indicated the suitable ranges of Ni and Mn for acceptable mechanical properties. In addition, optical microscopy and scanning electron microscopy were applied to link the microstructure with mechanical properties. The hardness of weld metals were found to increase linearly with Mn and Ni, which was attributed mainly to... 

Microstructure developments of X80 weld metal by the addition of different amounts of alloying elements such as nickel and manganese to the covering of electrodes were investigated. For this reason, samples were welded with electrodes that Ni value has changed between 0.8 and 3.5% in two critical amounts of Mn 0.7 and 1.6. Optical microscopy and scanning electron microscopy were applied for peer investigation of microstructure. Different phase percentages were obtained by Clemex software and compared in all samples. Results indicated that Ni and Mn change weld microstructure in the as-deposited zone and reheated part and corresponding to each alloying element concentration, amount of... 

Benzoins are rapidly oxidised to benzils in high yields by iodic acid supported on alumina under solvent-free conditions and microwave irradiation  

Semantic web search engines are evolving and many prototype systems and some implementation have been developed. However, there are some different views on what a semantic search engine should do. In this paper, a categorization scheme for semantic web search engines are introduced and elaborated. For each category, its components are described according to a proposed general architecture and various approaches employed in these components are discussed. We also propose some factors to evaluate systems in each category. © 2006 IEEE  

One of the important elements of the new generation of the Web is the emergence of blogs. Currently a considerable number of users are creating content using blogs. Although Persian blogs have a short history, they have improved significantly during this short period. Because of fundamental differences between Persian and other languages, limited work has been done to analyze Persian blogs. In this work, a system named BlogDisc for automatic discovery and accumulation of Persian blogs is developed. This system uses content as well as link structure of the blogs. As an important part of this research, we propose an algorithm to recognize blogs that are not hosted on special blog hosts. © 2007... 

A simple and environmentally benign procedure for the synthesis of 14-alkyl- or aryl-14H-dibenzo[a,j]xanthenes is described through a one-pot condensation of 2-naphthol with aryl or alkyl aldehydes in the presence of sodium hydrogen sulfate as a catalyst under solvent-free conditions. © 2008 Springer-Verlag  

A mixture of cobalt(II) and manganese(II) salts of 4-aminobenzoic acid supported on silica gel catalyses the oxidation of thiols to disulfides in the presence of oxygen or air  

Currently there is no standard test collection for evaluation of Farsi information retrieval systems. In this paper we introduce Mahak, the first complete test collection generally available for evaluating Farsi information retrieval systems. In addition, we have used different methods for constructing Mahak qrels and we have compared performance of these methods  

Question Answering systems are one of the hot topics in context of information retrieval. In this paper, we develop an open-domain Question Answering system for spatial queries. We use Google for gathering raw data from the Web and then in a few iterations density of potential answers will be increased, finally based on a couple of evaluators the best answers are selected to be returned to user. Our proposed algorithm uses fuzzy methods to be more precise. Some experiments have been designed in order to evaluate the performance of our algorithm and results are totally promising. We will describe that how this algorithm can be applied to other type of questions as well  

Several metrics have been proposed for recognition of relationships between elements of two Ontologies. Many of these methods select a number of such metrics and combine them to extract existing mappings. In this article, we present a method for selection of more effective metrics - based on data mining techniques. Furthermore, by having a set of metrics, we suggest a data-mining-like means for combining them into a better ontology alignment  

The efficient oxidative coupling of thiols to disulfides with N-chlorosuccinimide (NCS) at room temperature is described. Simple workup, economical method, high yields of products are some advantages of this method. © 2006 Taylor & Francis  

Montmorillonite K10-supported manganese(II) chloride was found to be an efficient and convenient catalyst for the oxidative cleavage of oximes, phenylhydrazones and semicarbazones to the corresponding carbonyl compounds with molecular oxygen. © 2006 Bentham Science Publishers Ltd