In this paper, the packing problem for complete (  4)-arcs in  is partially solved. The minimum and the maximum sizes of complete (  4)-arcs in  are obtained. The idea that has been used to do this classification is based on using the algorithm introduced in Section 3 in this paper. Also, this paper establishes the connection between the projective geometry in terms of a complete ( , 4)-arc in  and the algebraic characteristics of a plane quartic curve over the field  represented by the number of its rational points and inflexion points. In addition, some sizes of complete (  6)-arcs in the projective plane of order thirteen are established, namely for  = 53, 54, 55, 56.

لا يستطيع كل كائن حي أو كيان اجتماعي أداء دوره الذي يفترض أن يقوم به ما لم يمتلك الوسائل الكافية والضرورية لأداء ذلك الدور قال سبحانه وتعالى ((قال ربنا الذي أعطى كل شيء خلقه ثم هدى – طه 50)).

والنشاط الاقتصادي كجزء من الكيان الكلي للمجتمع لا يختلف عن هذه القاعدة، إذ عندما يراد من النظام الاقتصادي أداء دور فاعل فلا غنى له عن الوسائل التي تمكنه من أداء دوره المنشود. للنظام الاقتصادي مجمو

Biosorption of lead, chromium, and cadmium ions from aqueous solution by dead anaerobic biomass (DAB) was studied in single, binary, and ternary systems with initial concentration of 50 mg/l. The metal-DAB affinity was the same for all systems. The main biosorption mechanisms were complexation and physical adsorption of metallic cations onto natural active functional groups on the cell wall matrix of the DAB. It was found that biosorption of the metallic cations onto DAB cell wall component was a surface process. The main functional groups involved in the metallic cation biosorption were apparently carboxyl, amino, hydroxyle, sulfhydryl, and sulfonate. These groups were part of the DAB cell wall structural polymers. Hydroxyle groups (–O

synthesis and characterization of New schiff base Ligand Derived from 4-amino anti pyrine and it's complexes with some Metal lons and theirAntibacterial studies

Background: There is a clear debate about the role of bad oral habits (thumb-sucking and biting nails) and on oral health and the state of the dental caries, but there is no doubt that continuing these bad habits until advanced ages will lead to deep and difficult problems to solve. Objective: The purpose of study was to evaluate the effect of bad habits, include finger sucking and nail biting on dental caries among children aged from 6 to 10 years old. Subjects and methods: In Al-Hilla city, Iraq, a comparative study was conducted in which (200) primary school students aged between 6 to10 years old were involved. A questionnaire filled out by their parents was used to gather information related to the bad oral habit, and then all the stude