In this study a new composite material have been prepared and characterized through polymerization of ethylene glycol located between the Bentonite layers with phthalic anhydride. The results showed that the polymer binds with the structure of clay through hydrogen bonding also the polymerization process led to shatter of the three-dimension crystal structure of the clay and isolating layers in the form of nano-scale two-dimensional sheets, the polymer growth around the clay isolated layers work to increase the size particles at microscopic scale.                              &

New thermally stable aromatic poly(amide-imide)s ( PAI1- PAI4 ) were synthesized from direct polycondensation reaction of Terephthalic acid and Phthalic acid with two new different diamine monomers derivatives of 1,2,4,5-tetracarboxilic benzene dianhydride as a second diacides in a medium consisting of triphenyl phosphite (TPP) in N-methyl-2pyrrolidone (NMP) / pyridine solution containing dissolved calcium chloride CaCl2. The polymerization reaction produced a series of novel poly(amide-imide) in high yield. The new monomers were characterized by FTIR, 1H-NMR spectroscopy. The resulting polymers were typically characterized by means of FT-IR, 1H-NMR spectroscopy, and solubility tests. Thermal properties of the poly(amide-imide)s were als

New complexes of Cu (ll), Ni (ll), Co (ll), and Zn (ll) wi th 2-amino-5-p-Fiouro Phenyl 1, 3, 4-Thiadiazole have been synthesized. The products were isolated, studied and characterized by physical measurements, ie,(Ff-IR), UV-Vis and the melting points were determined. The new Schiff base (L) has been used to prepare some complexes. The prepared complexes were identified and their structural geometry were suggested

In this paper, we construct a new mathematical system as Multiplicative Cyclic Group (MCG), called a New Digital Algebraic Generator (NDAG) Unit, which would generate digital sequences with good statistical properties. This new Unit can be considered as a new basic unit of stream ciphers.

A (NDAG) system can be constructed from collection of (NDAG) units using a Boolean function as a combining function of the system. This system could be used in cryptography as like as Linear Feedback Shift Register (LFSR) unit. This unit is basic component of  a stream cipher system.

The aim of this paper is to present a method for solving high order ordinary differential equations with two point's boundary condition, we propose semi-analytic technique using two-point oscillatory interpolation to construct polynomial solution. The original problem is concerned using two-point oscillatory interpolation with the fit equal numbers of derivatives at the end points of an interval [0 , 1] . Also, many examples are presented to demonstrate the applicability, accuracy and efficiency of the method by comparing with conventional methods.

Oscillation criterion is investigated for all solutions of the first-order linear neutral differential equations with positive and negative coefficients. Some sufficient conditions are established so that every solution of eq.(1.1) oscillate. Generalizing of some results in [4] and [5] are given. Examples are given to illustrated our main results.

  The aim of this paper is to present a method for solving high order ordinary differential equations with two point's boundary condition, we propose semi-analytic technique using two-point oscillatory interpolation to construct polynomial solution. The original problem is concerned using two-point oscillatory interpolation with the fit equal numbers of derivatives at the end points of an interval [0 , 1] .  Also, many examples are presented to demonstrate the applicability, accuracy and efficiency of the method by comparing with conventional methods.

EDIRKTO, an Implicit Type Runge-Kutta  Method of Diagonally Embedded pairs, is a novel approach presented in the paper that may be used to solve 4th-order ordinary differential equations of the form . There are two pairs of EDIRKTO, with three stages each: EDIRKTO4(3) and EDIRKTO5(4). The derivation techniques of the method indicate that the higher-order pair is more accurate, while the lower-order pair provides superior error estimates. Next, using these pairs as a basis, we developed variable step codes and applied them to a series of -order ODE problems. The numerical outcomes demonstrated how much more effective their approach is in reducing the quantity of function evaluations needed to resolve fourth-order ODE issues.

     The oscillation property of the second order half linear dynamic equation was studied, some sufficient conditions were obtained to ensure the oscillation of all solutions of the equation. The results are supported by illustrative examples.

A reliable and environmental analytical method was developed for the direct determination of tetracycline using flow injection analysis (FIA) and batch procedures with spectrophotometric detection. The developed method is based on the reaction between a chromogenic reagent (vanadium (III) solution) and tetracycline at room temperature and in a neutral medium, resulting in the formation of an intense brown product that shows maximum absorption at 395 nm. The analytical conditions were improved by the application of experimental design. The proposed method was successfully used to analyze samples of commercial medications and verified throughout the concentration ranges of 25–250 and 3–25 µg/mL for both FIA and batch procedures, respecti