In this work, porous Silicon structures are formed with photochemical etching process of n-type Silicon(111) wafers of resistivity (0.02.cm) in hydrofluoric acid (HF) of concentration (39%wt) under light source of tungeston halogen lamp of (100 Watt) power. Samples were anodized in a solution of 39%HF and ethanol at 1:1 for 15 minutes. The samples were realized on n-type Si substrates Porous Silicon layers of 100m thickness and 30% of porousity. Frequency dependence of conductivity for Al/PSi/Si/Al sandwich form was studied. A frequency range of 102-106Hz was used allowing an accurate determination of the impedance components. Their electronic transport parameters were determined using complex impedance measurements. These measurements provide a powerful tool for interpretation of basic properties such as the dielectric constant, polarizibility and frequency dependence in the crystallites and trapping mechanisms. The electrical conductivity is mainly controlled by hoping transport on localized states in the chaotic porous structure
Chloroacetamide derivatives (2a-g) have been prepared through reaction of chloroacetyl chloride(1) (which prepared by the reaction of chloroacetic acid with thionyl chloride) with primary aromatic amines and sulfa compounds to afford compounds (2a-g) which then reacted with p-hydroxy benzaldehyde via Williamson reaction to obtaine the new compounds 2-(4-formyl phenoxy)-N-aryl acetamide (3a-g). Finally , compounds (3a-g) will be use as a good synthon to prepare the Schiff bases represented by compounds 2-(4-aryliminophenoxy)-N-arylacetamide (4a-g). through , reaction with some primary aromatic amine. All the prepared compounds were investigated by the available physical and spectroscopic methods.
In this paper, we consider inequalities in which the function is an element of n-th partially order space. Local and Global uniqueness theorem of solutions of the n-the order Partial differential equation Obtained which are applications of Gronwall's inequalities.
Mobile ad hoc network is nothing but the temporary network which is having the collection of mobile nodes. Routing and broadcasting are major operations of MANET network. The major operation in ad hoc mobile network is the broadcasting which sometime results to storm problem of the broadcast if the forwarding mechanism is not properly designated. Thus the challenges in the MANET are to reduce the broadcasting redundancy and under high transmission error rate provides high delivery ratio. Hence in our proposed research, we are introducing and investigating the new mechanism of broadcasting called Dual Covered Broadcast. This method takes the broadcast redundancy advantage order to improve packet delivery ratio especially under environments w
... Show MoreThis study aims to examine the main features of the new trends in agenda studies using the secondary analytic approach in analyzing the newest studies in agenda-setting issues from 2007 till 2017, in addition to the quantitative approach.
The researcher has analyzed 110 studies -75 foreign and 35 Arabic - to determine, describe and evaluate the key research trends which came in Arabic and foreign agenda-setting studies. The results confirmed that studies of the agenda theory are increasing steadily worldwide with diversity in the theoretical trends and used research tools. In addition, primary studies focus on content analysis and the survey approach (method). Also, most Arabic agenda-setting studies used the traditional methods and k
The cyanobacterial neurotoxin
Thin films of highly pure (99.999%) Tellurium was prepared by high vacuum technique (5*10-5torr), on glass substrates .Thin films have thickness 0.6m was evaporated by thermal evaporation technique. The film deposited was annealed for one hour in vacuum of (5*10-4torr) at 373 and 423 K. Structural and electrical properties of the films are studies. The x-ray diffraction of the film represents a poly-crystalline nature in room temperature and annealed film but all films having different grain sizes. The d.c. electrical properties have been studied at low and at relatively high temperatures and show that the conductivity decreases with increasing temperature at all range of temperature. Two types of conduction mechanisms were found to d
... Show MoreA laboratory investigation of six different tests were conducted on silty clay soil spiked with lead in concentrations of 1500 mg/kg. A constant DC voltage gradient of 1 V/cm was applied for all these tests with duration of 7 days remediation process for each test. Different purging solutions and addition configurations, i.e. injection wells, were investigated experimentally to enhance the removal of lead from Iraqi soil during electro-kinetic remediation process. The experimental results showed that the overall removal efficiency of lead for tests conducted with distilled water, 0.1 M acetic acid, 0.2 M EDTA and 1 M ammonium citrate as the purging solutions were equal to 18 %, 37 %, 42 %, and 29 %, respectively. H
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