A successful synthesis of SBA-15 with semi-spherical morphology and suitable texture properties was achieved using hydrothermal technique. Sodium silicate, derived from silica sand from Iraq, was used as a silica precursor, and Pluronic p123 triblock copolymer was used as a template with a strong acid media (pH < 1). The effect of adding (1–3) g of either polyvinyl alcohol (PVA), Polyvinyl pyrrolidone (PVP -k30), or Sodium dodecyl sulfate (SDS) dispersant agents on the texture properties of the synthesized SBA-15 was studied. The SBA-15 sample underwent various characterization techniques, including X-ray diffraction (XRD), Fourier transform infrared (FTIR), atomic force microscopy (AFM), nitrogen adsorption-desorption using Brunauer Emmett Teller (BET), and field emission scanning electron microscopy (FESEM). XRD analysis showed a single peak in the 2θ= 20–25°, indicating the presence of pure SBA-15. The FTIR spectroscopy results demonstrated presence of key functional groups like silanone, siloxane, and silanol. Using these dispersant agents had a discernible effect on the dispersion of particles to an average particle size distribution in a nanoscale range producing a high surface area of the prepared SBA-15 material, which ranged between 349 to 871 cm2/g, while not influencing the pore volume, and pore size, which are ranged between 0.17 to 0.43 cm3/g, and between 2 to 2.5 nm, respectively. Also, all prepared samples had a nano-scale range. The optimum texture properties were obtained using 2 g of PVP-k30 dispersion agent. Finally, it was observed that the spherical shape of SBA-15 particles was distorted by introducing more than 1 g of dispersion agents.
The problem of rebellion is considered one of the features of rapid changes that a society undergoes in all spheres and directions of life, especially in the realm of social relations, customs, traditions, values, and principles. Rebellion may manifest itself in rebellion against oneself, against values or traditions, or against social or governmental authority. One may find that submission plays a vital role in all of these interactions. This study deals with the problem of rebellion in the works of two renowned authors: The French Gustave Flaubert and the Israeli Amos Oz, through two main characters who share similar qualities and traits. Emma Bovary and Henna Konin demonstrate this through their rebellion against themselves, their relati
... Show MoreThe researcher tried to show the importance of obligation with the rules of professional conduct set by the Association of Accountants and Auditors of Iraqis when expressing an opinion the financial statements submitted tax administration and enhance the confidence of these lists, and adopted in the tax settling accounts process and its impact on tax revenues, and touched a researcher at the theoretical side of the search to the problem of research and of my Is there a trace of non- not to obligation by the rules of professional conduct in Iraq affect the tax revenue with the rules of professional conduct in tax revenue for companies research sample, the research aims to study the rules of professional conduct set by the Associatio
... Show MoreHedging is a linguistic avoidance of full commitment or precision. It is the use of a vague language. The main objectives of this study are to
... Show MoreLas diferencias entre el pretérito perfecto simple y el imperfecto son uno de los temas más complejos de la lengua española, no sólo para el estudiante, sino para el profesor, puesto que sistematizar los casos y hacerlos fácilmente comprensibles al alumno es tarea difícil. Los profesores de lengua, cuyas investigaciones han dado lugar a una serie de teorías y de corrientes metodológicas y didácticas que permiten enfocar la enseñanza de una lengua extranjera de manera muy distinta a como se hacía tradicionalmente. Vamos a repasar muy brevemente cuáles son estas teorías.
En primer lugar es necesario señalar en qué consiste el aprendizaje de una segunda lengua:
"El aprendizaje de una segunda lengua (L2) es el
... Show MoreThe aim of the present study is to examine the effectiveness of a proposed unite in voluntary work in enhancing critical thinking skills and the attitudes towards responsible citizenship among eighth grade female students in the Sultanate of Oman. In order to collect the study data, the researchers employed a quasi-experimental research design with twenty female students from Al-Sideeqah bint Al-Sideeq for basic education school. The research data were collected via a critical thinking test that consisted of twenty-five items and a scale of twenty items under three different dimensions, which aimed to measure students' attitudes towards responsible citizenship. The researchers implemented these two instruments as pre- and post the experi
... Show MoreThe research aims to show the relationship between the use of automated accounting systems technology and its impact on enhancing the efficiency and effectiveness of the internal control system in a sample of Bahraini universities in light of the rapid changes in the electronic business environment. Automated accounting and its impact on enhancing the efficiency and effectiveness of the internal control system, and it is concluded through the analytical study of the research sample that there is a percenta
... Show MoreThe last ten years observed a shift enormous scientific in the method and way that it deals professional with the cost accounting and reflected the result those shift enormous scientific of increase the competitive environmental that accompanied the emergence of a modern manufacturing environmental on surface the long roductive life and emergence advanced information technology that give a central focus of his important on client with growing global markets growth on a large scale.
The research aim to define the concept of cost awareness, the concept and methods of strategic cost management and the role of cost awareness for managers of industrial units in strategic of cost managem
... Show MoreThe present art icle discusses the prob lems of understanding and translating the lingu istic and cult ural aspect of a foreign lite rary text. The article considers the trans lation process through the pr ism of cult ural orientation. In the process of transl ation, the nati onal cultural iden tity should be expressed to the max imum extent, through all me ans of expre ssion that include imagery and inton ation. In addi tion to the author's sty le, special atte ntion should al so be pa id to tro pes, phraseological uni ts, colloquial wo rds and dial&n
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