Abstract: Monitoring the concentrations of heavy metals in natural and waste water at and below the level of their maximum permissible concentrations is an urgent environmental problem. Hence, new procedures for the preconcentration of heavy metals with their subsequent determination by different methods are required. Along with other sorbents, significant attention is attracted to polymer chelating sorbents, which provide individual or group extraction of trace elements, eliminate matrix effects, and provide high concentration factors. The effect of the various parameters such as electrochemically and chemically synthesis methods, physical oxidation state of the polymer, polymer thickness, solution pH and metal ion concentration on the adsorption, kinetics and efficiency were investigated. The results showed a vary broad concentration range of the heavy metals from (0.05 to 10 mg/L) can be adsorbed on different kinds of polymers at different pH values and different efficiently. The adsorption capacity of the polymer to different concentrations of heavy metals was evaluated as the milligram of metal ions by one gram of various forms of the polymer. The DC conductivity measurements were also employed on the solid polymer before and after adsorption of metal ions. The experimental adsorption date was fitted to different mathematical isotherms to estimate the binding constant of heavy metals with the polymer in both single and mixed ion solutions. The method provides the extraction of analytes from natural water of complex composition containing high concentrations of alkali, alkaline-earth and other elements and is characterized by rapidly, selectivity, low detection limits, and a high reproducibility of the results. The relative standard deviation is 2-4%. The technique was test with real waste water samples.  

Usually fin represent as one of the important structures in all type of airplane and the fin structure was greatly improved, especially for modern supersonic speed constructions. The main aim of delta fin construction is to minimize the weight of structure as much as possible and keeping the stiffness of material structural in margin of safety under design load [1]. The primary difference between classical method and finite element are the view structure and the ensuring solution procedure. Classical method considers the structure as a continuum whose behavior is governed by partial or ordinary differential equations [2]. By using finite element method consider the structure to be an assembly of small finite-sized particles. The behavior of the particles and the overall structure is obtained by formulating a system of algebraic equation that can be readily solved by developed methodology, which will be presented in form of software.

Research was conducted at Curtin University (Western Australia) to assess the seedling tolerance of three species Eucalyptus, gomphocephala DC (Myrtaceae) (common name ‘Tuart’), Eucalyptus marginata Sm. (common name ‘Jarrah’) and Corymbia calophylla (Lindl.) K.D. Hill & J. A. S. Johnson (common name ‘Marri’) to soil-induced stressor, namely water loggings (flooding). Flooding treatment was achieved by filling the tubs with water, approximately 1 cm above the soil surface and control treatment had the same method except with drainage holes. Study assessment was attained by statistical change in seedling growth, leaf allocation and leaf physiology after 70 days of seed germination. Tolerance was assessed by measuring changes in seedling growth, leaf allocation and leaf physiology after 70-80 days. C. calophylla was the most tolerant to prolonged waterlogging (80% survival, no difference in transpiration rates); E. marginata was the least tolerant (10% survival, 95% decrease in transpiration rate). E. marginata was the least tolerant to the three soil stresses. E. marginata prefers habitats that are not excessively wet on well-drained soils. C. calophylla was the most tolerant, occurring and tolerating wet, well-drained soils and thus demonstrated better physiological responses of three prominent studied eucalypts to soil-induced stresses provides us with invaluable knowledge for rehabilitating and restoring urban bush land.tolerance to prolong waterlogging. Knowing the seedling growth and

This work is focused on nucleation stages during isothermal austenite transformation in two types of Vanadium micro-alloyed steels. Isothermal treatment was carried out in the temperature range 350 to 600οC. Metallographic evaluation using optical and scanning electron microscopy (SEM) enabled determination of the nucleation curves of isothermally decomposed austenite. Three curves are found to be relevant to this initiation stage of transformation: first curve is related to grain boundary nucleated ferrite (GBF), second curve is related to intra-granularly nucleated ferrite (IGF) and the third to pearlite (P) curve. GBF and IGF curves are divided into two regions, which represents the high temperature and the low temperature segments as consequence of either displacive nature of transformation or diffusion transformation. Addition of Ti to V – micro-alloyed steel in this work seems to be balanced by a slightly higher C and Mn content, leading to limited effect on nucleation stage of austenite decomposition.

In this contribution, vertically aligned carbon nanotubes were synthesized by chemical vapor deposition (CVD). The effects of intrinsic disorders constructed by mobile surface contaminants on the structural perfection of carbon nanotubes (CNTs) were investigated. The results indicated a complete picture on the effect of the involved parameters on the lattice defects of modulated CNTs based on the cooling step. Raman scattering showed that the different cooling methods of the CVD preforms altered the bound complex defects of the structure of the CNTs. Moreover, an array of CNTs was removed from the silicon substrate by applying the neutralized cooling method on the CVD, while the vertical and parallel orientations were retained. The FESEM images, coupled with Raman spectroscopy results, confirm the morphological improvements of the growth CNTs based on the neutralized cooling method.