Biodiesel can be prepared from various types of vegetable oils or animal fats with the aid of a catalyst.
Calcium oxide (CaO) is one of the prospective heterogeneous catalysts for biodiesel synthesis. Modification
of CaO by impregnation on silica (SiO2) can improve the performance of CaO as catalyst. Egg shells and rice
husks as biomass waste can be used as raw materials for the preparation of the silica modified CaO catalyst.
The present study was directed to synthesize and characterize CaO impregnated SiO2 catalyst from biomass
waste and apply it as catalyst in biodiesel synthesis. The catalyst was synthesized by wet impregnation
method and characterized by x-ray diffraction, x-ray fluorescence, nitrogen adsorption-desorption, and
basicity density. The activity of the catalyst in biodiesel synthesis was assayed at different molar ratios of
palm oil to methanol ranging from 1:6, 1:9, 1:12 and 1:15. The biodiesel composition was determined by gas
chromatography-mass spectroscopy and the properties of the biodiesel were also characterized. The results
showed that the CaO impregnated SiO2 catalyst was successfully synthesized based on confirmation by XRD
and XRF. The catalyst has a surface area, average pore diameter, total pore volume, and basicity density of
19.38 m2
/g, 3.22 nm, 0.0122 cm3
/g, and 3.4 mmol/g, respectively. The catalyst activity assay indicates that
the molar ratio of palm oil to methanol of 1:12 is the optimum condition for biodiesel synthesis. At this
molar ratio, 81.4% biodiesel yield was achieved, and it met the quality standards according to ASTM D
6751.
In this study, gold nanoparticle samples were prepared by the chemical reduction method (seed-growth) with 4 ratios (10, 12, 15 and 18) ml of seed, and the growth was stationary at 40 ml. The optical and structural properties of these samples were studied. The 18 ml seed sample showed the highest absorbance. The X- ray diffraction (XRD) patterns of these samples showed clear peaks at (38.25o, 44.5o, 64.4o, and 77.95o). The UV-visible showed that the absorbance of all the samples was in the same range as the standard AuNPs. The field emission-scanning electron microscope (FE-SEM) showed the shape of AuNPs as nanorods and the particle size between 30-50 nm. Rhodamine-610 (RhB) was prepared at 10<
... Show MoreArabic calligraphy is one of the greatest achievements of Islamic art. The visual form of Arabic calligraphy is the primary means of presenting ideas and messages for expressive communication in Arabic typefaces. Emerging computer technology with calligraphy is essential for effective visual designs; however, traditional typefaces are insufficient in number and quality to fulfill the requirements of the current Saudi industry. Thus, this research investigates the processes followed by graphic designers to create modern Arabic type designs inspired by Arabic calligraphy, and presents the characteristics of Arabic calligraphy. The research implemented a mixed experimental and descriptive method, exploring 10 typefaces designed by professio
... Show MoreThe current study monitors the mechanisms of formation of the actor's performance expressive system (voice and motion) and the levels of their construction consistent with the aesthetic premise of the theatrical performance through incorporating what is natural, materialistic (physiological) and artistic and philosophical virtual (aesthetic ), through which the creative actor seeks not to repeat the image and substance of a thing according to its natural life image, in favor of new aesthetic reproduction governed by a group of significant relationships formed according to (artistic and philosophical) characteristics and features that distinguish the artistic accomplishment from its reality(its natural and functional reference). According
... Show MoreThis paper studies the combination of fluid viscous dampers in the outrigger system to add supplementary damping into the structure, which purpose to remove the dependability of the structure to lower variable intrinsic damping. This optimizes the accuracy of the dynamic response and by providing higher level of damping, basically minimizes the wanted stiffness of the structure while at the same time optimizing the achievement.
The modal considered is a 36 storey square high rise reinforced concrete building. By constructing a discrete lumped mass model and using frequency-based response function, two systems of dampers, parallel and series systems are studied. The maximu
... Show MoreThis study is one of the descriptive studies, where the researcher used the survey method, which seeks to provide an accurate and appropriate description of the main and sub-categories of the content of the research for television documentaries on the Iraqi satellite channel, relying on the research questions and objectives to analyze the content of the documentaries according to the approach referred to above. The objectives of the research were summarized to identify the function of the documentary programs in Al-Iraqiya channel to detect the crimes of the former regime, to know the frameworks highlighted by the documentary programs in Al-Iraqiya channel to reveal the crimes of the former regime, to identify the extent of the circ
... Show MoreThe launch of the EU’s Eastern Partnership in 2009 intended to signal a new, elevated level of EU engagement with its Eastern neighborhood. Yet there remain several long-simmering and potentially destabilizing conflicts in the region, with which EU engagement thus far has been sporadic at best. The Union’s use of its Common Security and Defense Policy (CSDP) in the region and to help solve these disputes has been particularly ad hoc and inconsistent, wracked by inter-institutional incoherence and undermined by Member States’ inability to agree on a broad strategic vision for engagement with the area.
The three CSDP missions deployed to the region thus far have all suffered from this incoherence to various extents. In particu
... Show MoreAbstract:
Interest in the topic of prediction has increased in recent years and appeared modern methods such as Artificial Neural Networks models, if these methods are able to learn and adapt self with any model, and does not require assumptions on the nature of the time series. On the other hand, the methods currently used to predict the classic method such as Box-Jenkins may be difficult to diagnose chain and modeling because they assume strict conditions.
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The reasons for the totality are varied and multiple, some of which are attributed to the methods of the Arabic language as the participant
Verbal and omnipotent differences in the oud of conscience, which are comprehensive reasons for language in all
And some of these reasons are due to the sciences of the Qur'an, such as cessation and initiation
The explanation of the explanation for the multiplicity of words and differences in them, which necessarily led to a dispute jurisprudence
Linked to the origin of disagreement in the interpretation of the totality and its orientation and understanding and to summarize this subject and diverge
Parts and vocabulary did not receive the necessary care and did not absorb the lesson an