In this work we prepared some schiff bases by condensation urea and benzaldehyde or its derevative ( bromo benzaldehyde or hydroxy benzaldehyde ) as ( 1 : 1 ) mole ( urea : benzaldehyde or its substitution ) to prepare compounds ( A1 , B1 , C1 , D1 , E1 , F1 , G1 ) and ( 1 : 2 ) mole ( urea : benzaldehyde or its substitution ) to prepare compounds ( A2 , B2 , C2 , D2 , E1 , F2 , G2 ) . The prepared compounds identified spectroscopic by infrared spectroscopy FT-IR and Thin layer chromotography T.L.C . The force constant calculated from the wave number for the carbonyl stretching from FT-IR chart and by using the following equation K = 4?2C2?'2? The change in double bond order for carbonyl deteremined in according with some past research by compare the force constant for the prepared compounds with the force constant in past research and calculated bond order statistically by extract the curve equation and calculated the bond order by application curve equation .
In the current study, haemoglobin analytes dissolved in a special buffer (KH2PO4(1M), K2HPO4(1M)) with pH of 7.4 were used to record absorption spectra measurements with a range of concentrations from (10-8 to 10-9) M and an absorption peak of 440nm using Broadband Cavity Enhanced Absorption Spectroscopy (BBCEAS) which is considered a simple, low cost, and robust setup. The principle work of this technique depends on the multiple reflections between the light source, which is represented by the Light Emitting Diode 3 W, and the detector, which is represented by the Avantes spectrophotomer. The optical cavity includes two high reflectivity ≥99% dielectric mirrors (dia
... Show MoreThe effects of Internet use on university’s students:The effects of Internet use on university’s students:“A Study on a Sample of Jordanian University’s students "This survey aims to identify the most important effects of Internet use on Jordanian public and private universities’ students by monitoring and analyzing a set of indicators that show the quality of the effects on specific fields such as cultural, social, psychological, moral and political effects .To achieve these goals, the study attempts to answer the following questions:1. What are the effects of Internet’s use on students?2. What is the relationship between the effects and demographic variables such as gender, age, family size an
... Show MoreThis prospective study involved one hundred patients with colostomies admitted at the Central Pediatric Teaching Hospital for colostomy closure over the period of two years (Jan.2000-
Jan2002).
Patients were divided in to two groups according to the technique of colostomy closure. In the first group, the closure was done by single layer of interrupted non-absorbable suture material; in the second group closure was done by double layer suturing technique. All patients were prepared by the same conventional method including fluid diet for three days
followed by two days washing enemas before operation with antimicrobial prophylaxis agents. Of these one hundred patients;(48) presented as cases of Hirschspr
The Phenomena of Double Taxation becomes a problem that all countries suffer from it specially developing countries where the double taxation becomes an obstacle before investments. Thus the world countries attempt to find a solution
or this problem through national and international agreements
The quality of Global Navigation Satellite Systems (GNSS) networks are considerably influenced by the configuration of the observed baselines. Where, this study aims to find an optimal configuration for GNSS baselines in terms of the number and distribution of baselines to improve the quality criteria of the GNSS networks. First order design problem (FOD) was applied in this research to optimize GNSS network baselines configuration, and based on sequential adjustment method to solve its objective functions.
FOD for optimum precision (FOD-p) was the proposed model which based on the design criteria of A-optimality and E-optimality. These design criteria were selected as objective functions of precision, whic
... Show MoreAbstract
In this work, the plasma parameters (electron temperature (Te), electron density( ne), plasma frequency (fp) and Debye length (λD)) have been studied by using the spectrometer that collect the spectrum of Laser produce CdTe(X):S(1-X) plasma at X=0.5 with different energies. The results of electron temperature for CdTe range 0.758-0.768 eV also the electron density 3.648 1018 – 4.560 1018 cm-3 have been measured under vacuum reaching 2.5 10-2 mbar .Optical properties of CdTe:S were determined through the optical transmission method using ultraviolet visible spectrophotometer within the r
... Show MoreThis work is concerned with the design and performance evaluation of a shell and double concentric tubes heat exchanger using Solid Works and ANSY (Computational Fluid Dynamics).
Computational fluid dynamics technique which is a computer-based analysis is used to simulate the heat exchanger involving fluid flow, heat transfer. CFD resolve the entire heat exchanger in discrete elements to find: (1) the temperature gradients, (2) pressure distribution, and (3) velocity vectors. The RNG k-ε model of turbulence is used to determining the accurate results from CFD.
The heat exchanger design for this work consisted of a shell and eight double concentric tubes. The number of inlets are three and that of o
... Show MoreBackground: Recent implant surgical approach aims to cause less trauma, invasiveness and pain as much as possible and to reduce patient and surgeon discomfort, time of surgery and time needed for functional implant loading. Flapless surgical techniques considered recently as one of the most popular techniques that may achieve these aims especially enhancing osseointegration and subsequently implant stability within less time than the traditional flapped surgical technique. So this study aimed to make a comparison between flapped and flapless surgical techniques in resulted implant stability according to resonance frequency analysis RFA and in duration of surgical operation. Materials and methods: A total of 26 patients with 41 implants (o
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