Porous silicon (P-Si) has been produced in this work by photoelectrochemical (PEC) etching process. The irradiation has been achieved using diode laser of (2 W) power and 810 nm wavelength. The influence of various irradiation times on the properties of P-Si material such as P-Si layer thickness, surface aspect, pore diameter and the thickness of walls between pores as well as porosity and etching rate was investigated by depending on the scanning electron micrograph (SEM) technique and gravimetric measurements.

Freedom of opinion and expression occupy the first place among the concerns of countries and international organizations. And it is also the basis of contemporary freedom because it is the foundation for achieving freedom in other fields such as politics, economics, education, etc.. The constitutions of the state have ensured that almost the entire freedom to express an opinion in all its forms either orally or writing or images of expressions, but these freedoms are identified within the law. Most countries announced their commitment to the international conventions and texts issued by international and regional organization like the Universal Declaration of Human Rights in 1948, and the International Covenant on Civil and Political Rig

In the present study, the growth and total lipid contents of two oleaginous fungal isolates Aspergillus terreus, Aspergillus fumigatus were compared in different nitrogen and organic carbon sources.  Artificially the fungi were cultured on media consisting of various mono- or di- or polysaccharides and  peptone or yeast extract as elementary sources for carbon and nitrogen, respectively. Media containing sucrose /yeast extract or glucose/ yeast extract were the most effective for lipid production from fungal, during  two weeks  incubation period, the highest biomass of dry weight was (19.6 , 18.8) g / L , (25.8 , 30.5) g /L  and  lipid yield (1, 0.97 )g/L, (0.65, 0.65) g/ L for two isolates Aspergillus terreus

Light is an important factor that influences the growth and photosynthetic efficiency of microalgae; however, little is known about how light intensity together with the wavelength affect the photosynthetic capacity and growth of marine microalgae. In the present study, the growth of the marine green microalga Dunaliella parva was studied and optimized under different light intensities (25 ~ 70 μmol m^-2 s^-1) and qualities (blue, green, and red) in comparison with white light at 40 μmol m^-2 s^-1 as a control. The growth was monitored by counting the cell number, pigment content, Chl a, Chl b, and carotenoids concentrations. The optimal growth and highest photosyntheti

The study aims to identify the theoretical literature for all the variables of the study (ICT, GDP) as well as to identify the practical side of the impact of ICT on the per capita GDP in Iraq for the period (2004-2021). The study was based on the hypothesis that ICT impacts per capita GDP in Iraq. The problem of the study was to answer the question: does ICT contribute to per capita GDP? The study concluded that an increase in the rate of internet users per 100 people by one unit would increase. Increasing the landline telephone rate per 100 people by one unit will increase GDP per capita. In addition, increasing the mobile phone rate per 100 people by one unit will increase GDP per capita. The study recommended adopting rational poli

The study aims detection teaching modalities adopted relationship in Jerash University exactly the classroom, and to achieve the goal of the study was to develop a questionnaire consisting of (39) items, and was achieving validity and reliability have, then sent to a sample of professors made up the university from (122) university professor of the total (172) professor, and they study population.

     Study found a relationship between the teaching methods of the four their strategies with classroom management, and as a result the overall average level, while Hspt critical thinking at the highest correlation with classroom discipline management relationship strategy, while the relatio

Objective: This experiment was conducted to study the effects of ionized water on certain egg quality traits and the levels of proteins and enzymes in the blood of the Japanese quail Coturnix japonica . Materials and Methods: One hundred 42-day-old quail were randomly distributed among five treatment groups with four replicates for each group. The following treatments were used: T1 (control): The birds were provided normal water, T2: The birds were provided alkaline water (pH = 8), T3: The birds were provided alkaline water (pH = 9), T4: The birds were provided acidic water (pH = 6) and T5: The birds were provided acidic water (pH = 5). A Complete Randomized Design (CRD) was used to investigate the effects of the studied treatments on diffe

The influence of fear on the dynamics of harvested prey-predator model with intra-specific competition is suggested and studied, where the fear effect from the predation causes decreases of growth rate of prey.  We suppose that the predator attacks the prey under the Holling type IV functional response. he existence of the solution is investigated and the bounded-ness of the solution is studied too. In addition, the dynamical behavior of the system is established locally and globally. Furthermore, the persistence conditions are investigated. Finally, numerical analysis of the system is carried out.

Frictional heat is generated when the clutch starts to engag. As a result of this operation the surface temperature is increased rapidly due to the difference in speed between the driving and driven parts. The influence of the thickness of frictional facing on the distribution of the contact pressure of the multi-disc clutches has been investigated using a numerical approach (the finite element method). The analysis of contact problem has been carried out for a multiple disc dry clutch (piston, clutch discs, separators and pressure plate). The results present the distribution of the contact pressure on all tShe surfaces of friction discs that existed in the friction clutch system. Axisymmetric finite element models have been developed to ac