An efficient modification and a novel technique combining the homotopy concept with Adomian decomposition method (ADM) to obtain an accurate analytical solution for Riccati matrix delay differential equation (RMDDE) is introduced in this paper . Both methods are very efficient and effective. The whole integral part of ADM is used instead of the integral part of homotopy technique. The major feature in current technique gives us a large convergence region of iterative approximate solutions .The results acquired by this technique give better approximations for a larger region as well as previously. Finally, the results conducted via suggesting an efficient and easy technique, and may be addressed to other non-linear problems.
The subject of demand on oil derivative has occupied an important position at present time in the daily life context. The fuel of benzene and gas oil and kerosene is one of basic elements of that concern, and on local , regional and international levels. The oil derivatives have played a leading role in determining the course and nature of development since early 1970 to the present time whether in the productive Arab countries or the importing. The researcher set out from the hypothesis that the increase of the local consumer demand on some of the oil derivatives is because of the internal and external factors accompanied by the inability of the productive capability and local production to confront this increase, and the resort
... Show MoreAn energy and exergy thermodynamic analysis using EES program was done for a domestic refrigerator working with R-134a using vapor compression refrigeration cycle. The analysis deals with the system component, i.e. compressor, condenser, evaporator and the expansion device. The analysis depends on the entropy generation minimization approach to improve the refrigerator performance by exploring the optimum design points. These design points were derived from three different theories governing the entropy generation minimization using exergy analyzing method. These theories were first applied to find the optimum balance between the hot inner condenser area and the cold inner evaporator area of the refrigerator and between
... Show MoreUnderstanding how abiotic influences affect organisms and their interactions within ecological communities has long been of interest to ecologists. The significance of this comprehension has increased given rapid human-induced climate change. Wind speed variation is one of the less researched effects of climate change, as wind speeds worldwide are generally falling. Although wind is a fairly universal component of the environment, relatively little work has been conducted to integrate our knowledge of how wind affects interactions between different species. In this study, the influence of wind on bottom-up trophic interactions in the plant–ungulate–wolf food chain has been investigated through mathematical modeling. Positivity and bound
... Show MoreThis paper examines the use of one of the most common linguistic devices which is hyperbole. It shows how hyperbolic devices are used as an aspect of exaggeration or overstatement for an extra effect in which the speaker can use hyperbole to add something extra to a situation in order to exaggerate his idea or speech. It is, like other figures of speech, used to express a negative or positive attitude of a specific unit of language. Thus, this paper is set against a background of using hyperbole concerning two main fields (advertisements and propaganda). So, the use of hyperbole will be implied by analyzing them concerning their meaning) literal and non-literal). Methodology of this
... Show MoreFilms of PMMA and copper sulphate doped PMMA have been prepared by casting method. Absorbance and transmittance spectra were recorded in the wavelength range (300-900) nm in order to calculate, single oscillator energy, dispersion energy, average oscillator strength, the refractive index at infinite wavelength, M-1 and M -3 moments of the optical spectra, it was found that all these parameters were effected by doping.
In this work, the plasma parameters (electron temperature and
electron density) were determined by optical emission spectroscopy
(OES) produced by the RF magnetron Zn plasma produced by
oxygen and argon at different working pressure. The spectrum was
recorded by spectrometer supplied with CCD camera, computer and
NIST standard of neutral and ionic lines of Zn, argon and oxygen.
The effects of pressure on plasma parameters were studied and a
comparison between the two gasses was made.
Coumarin derivatives have shown different biological activities, such as antifungal, antibacterial antiinflammatory, and antioxidant activities, besides antibiotic resistance modulating effects, and anti-HIV, hepatoprotective, and antitumor effect. So, new coumarin derivatives (hydrazones and an amide) were synthesized through multisteps reactions. All the synthesized target compounds were characterized by FT-IR spectroscopy, 1HNMR analysis. The compounds then evaluated for their anti-bacterial activity by means of well-diffusion method against two gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae) and two gram-negative bacteria (E.coli and Pseudomonas aeruginosa). The highest activity was demonstr
... Show MorePhysical adsorption by nitrogen gas was studied on seven commercial platinum reforming catalysts (RG-402, RG-412, RG-432, RG-451, RG 422,RG-482, PS-10), four prepared platinum catalysts (0.1%Pt/alumina, 0.2 %Pt/alumina, 0.45 %Pt/alumina and 0.55% Pt/alumina), and -alumina support. Physical adsorption was carried out by using Accelerated Surface Area and Porosimetry (ASAP 2400 device) at 77 K . The results indicate that the surface area in genaral decreases with increasing platinum percentage, high platinum loaded (0.45% and 0.55%) it was found that the percent increasing in surface area was lower than those obtained for low platinum loaded catalysts , and at very higher platinum loading 0.6 %Pt , some reduction in surface area was
... Show MoreFilms of pure Poly (methyl methacrylate) PMMA and Iron chromate doped PMMA have been prepared using casting method. Transmission and absorptance spectra have been recorded in the wavelength range (300-900) nm, in order to calculate, single oscillator energy, dispersion energy proposed by Wemple - DiDomenico model, average oscillator strength, average oscillator wavelength. The refractive index data at infinite wavelength which was found to obey single oscillator model which was found to increase from 2.27-2.56 as the doping percentage increase. The decreasing in the optical energy gap which was found according to Tauc model were (3.74-3.63) eV , is in good agreement with that obtained by wimple-DiDomenico model. The inverse behavior comp
... Show MoreSelexipag is an orally selective long-acting prostacyclin receptor agonist, which indicated for the treatment of pulmonary arterial hypertension. It is practically insoluble in water ( class II, according to BCS). This work aims to prepare and optimized Selexipag nanosuspensions to achieve an enhancement in the in vitro dissolution rate. The solvent antisolvent precipitation method was used for the production of nanosuspension, and the effect of formulation parameters (stabilizer type, drug: stabilizer ratio, and use of co-stabilizer) and process parameter (stirring speed) on the particle size and polydispersity index were studied. SLPNS prepared with Soluplus® as amain stabilizer (F15) showed the smallest particle size 47nm wi
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