Mobile ad hoc network security is a new area for research that it has been faced many difficulties to implement. These difficulties are due to the absence of central authentication server, the dynamically movement of the nodes (mobility), limited capacity of the wireless medium and the various types of vulnerability attacks. All these factor combine to make mobile ad hoc a great challenge to the researcher. Mobile ad hoc has been used in different applications networks range from military operations and emergency disaster relief to community networking and interaction among meeting attendees or students during a lecture. In these and other ad hoc networking applications, security in the routing protocol is necessary to protect against malicious attacks as well as in data transmission. The goal of mobile ad hoc security is to safeguard the nodes’ operation and ensure the availability of communication in spite of adversary nodes. The node operations can be divided into two phases. The first phase is to discover the route (s) path. The second phase is to forward the data on the available discovered routes. Both stages need to protect from attacks; so many protocols have been proposed to secure the routing and data forwarding. This is a review study to mobile ad hoc protocols for securing routing as well as protocols for securing packets forwarding. Furthermore, it will present the characteristics and the limitations for each protocol and attributes.
In this work the strain energy of tetrahedrane and its nitrogen substituted molecules were calculated by isodesmic reaction method according to DFT quantum chemical fashion, the used basis set was 6-31G/B3-LYP, in addition all structures were optimized by RM1 semi-empirical method. From the obtained data we estimate an empirical equation connect between strain energy of the molecule with charge functions represented by dipole moment of the molecule plus accumulated charge density involved within the tetrahedron frame plus the number of nitrogen atoms. The results indicate the charge spreading factors by polarization and processes are the most important factors in decreasing the strain energy.
In this research, the preparation of bidentate Schiff base was carried out via the condensation reaction of both the salicylaldehyde with 1-phenyl-2,3-dimethyl-4-amino-5-oxo-pyrazole to form the ligand (L). The mentioned ligand was used to prepare complexes with transition metal ions Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The resulting complexes were separated and characterized by FTIR and UV-Vis spectroscopic technique. Elemental analysis for Carbon, Hydrogen and Nitrogen elements, electronic spectra of the ligand and complexes were obtained, and the magnetic susceptibility tests were also achieved to measure the dipole moments. The molar conductivities were also measured and determination of chlorine content in the complexes and
... Show More
Alkaloids are regarded as important nitrogen-containing chemical compounds that serve as a rich source for discovering and developing new drugs where most plant-origin alkaloids have antiproliferation effects on different kinds of cancers. Alkaloids’ continence of Calotropis procera leaves are detected by two biochemical alkaloid reagents. Also GC-MS analysis for leaf alkaloid extract was done that showed the existence of one type of alkaloid compound at retention time12.8min detected as colchicine (C22H25N06( by comparing it with colchicine standard reference (Sigma Aldrich) with M.wt 399g/mol and percentage area 7.1%. Furthermore, identification, separation, and purification
... Show MoreAbstract
Praise be to Allah, The Lord of the worlds, and peace be upon
Muhammad the master of former and latter people, and peace be upon His
relatives, companions and those who followed Him to Judgment day.
After recognizing the prescription which is called (Al- Fadhaly's Thesis in
parsing of "There is no god but God") as it is related with the word of the
investigation of this issue attracted me, as being related with the idea of the
only one God that is mentioned in the prophetic speech, which is said by
Anas- God satisfies him- Who said, Said the Messenger Muhammad peace
be upon him " Goes out of the Hell who said: there is no god but God, and in
his heart a hair weight of charity, and goes out of the He
In this work, metal oxides nanostructures, mainly, copper oxide (CuO), nickel oxide (NiO), titanium dioxide (TiO2), and multilayer structure were synthesized by dc reactive magnetron sputtering technique. The structural purity and nanoparticle size of the prepared nanostructures were determined. The individual metal oxide samples (CuO, NiO and TiO2) showed high structural purity and minimum particle sizes of 34, 44, 61 nm, respectively. As well, the multilayer structure showed high structural purity as no elements or compounds other than the three oxides were founds in the final sample while the minimum particle size was 18 nm. This reduction in nanoparticle size can be considered as an advantage for the dc reactive magnetron sputtering tec
... Show MoreIn this work, metal oxide nanostructures, mainly copper oxide (CuO), nickel oxide (NiO), titanium dioxide (TiO2), and multilayer structure, were synthesized by the DC reactive magnetron sputtering technique. The effect of deposition time on the spectroscopic characteristics, as well as on the nanoparticle size, was determined. A long deposition time allows more metal atoms sputtered from the target to bond to oxygen atoms and form CuO, NiO, or TiO2 molecules deposited as thin films on glass substrates. The structural characteristics of the final samples showed high structural purity as no other compounds than CuO, NiO, and TiO2 were found in the final samples. Also, the prepared multilayer structures did not show new compounds other than th
... Show MoreIn this work, multilayer nanostructures were prepared from two metal oxide thin films by dc reactive magnetron sputtering technique. These metal oxide were nickel oxide (NiO) and titanium dioxide (TiO2). The prepared nanostructures showed high structural purity as confirmed by the spectroscopic and structural characterization tests, mainly FTIR, XRD and EDX. This feature may be attributed to the fine control of operation parameters of dc reactive magnetron sputtering system as well as the preparation conditions using the same system. The nanostructures prepared in this work can be successfully used for the fabrication of nanodevices for photonics and optoelectronics requiring highly-pure nanomaterials.