In this research, the effect of multi-walled carbon nanotubes (MWCNTs) on the alumina/chromia (Al2O3/Cr2O3) nanocomposites has been investigated. Al2O3/Cr2O3-MWCNTs nanocomposites with variable contents of Cr2O3 and MWCNTs were fabricated using coprecipitation process and followed by spark plasma sintering. XRD analysis revealed a good crystallinity of sintered nanocomposites samples and there was only one phase presence of Al2O3-Cr2O3 solid solution. Density, Vickers microhardness, fracture toughness and fracture strength have been measured in the sintered samples. The results show that the relative density, microhardness and fracture strength of nanocomposites are significantly improved at low contents of Cr2O3 and MWCNTs. The increase of MWCNT’s content in the nanocomposites has adversely affected due to increasing the tangle and interaction of MWCNTs with each other, which leads to agglomeration in the nanocomposites. Increasing of Cr2O3 content in nanocomposites increases formation of Al2O3-Cr2O3 solid solution that actually requires the high sintering temperature to achieve good densification. The fracture toughness of Al2O3/Cr2O3-MWCNTs nanocomposites was enhanced by increasing the carbon nanotube content.
Abstract
Hexapod robot is a flexible mechanical robot with six legs. It has the ability to walk over terrain. The hexapod robot look likes the insect so it has the same gaits. These gaits are tripod, wave and ripple gaits. Hexapod robot needs to stay statically stable at all the times during each gait in order not to fall with three or more legs continuously contacts with the ground. The safety static stability walking is called (the stability margin). In this paper, the forward and inverse kinematics are derived for each hexapod’s leg in order to simulate the hexapod robot model walking using MATLAB R2010a for all gaits and the geometry in order to derive the equations of the sub-constraint workspaces for each
... Show MoreGlobalization as phenomena has affected all aspects of life and reflected its impacts to the Arab world politically, economically, and culturally and became a vital field that related directly to our life. This field of searching needs as many studies and Academics as for employing the means that needed to face a national challenge which targeting the Arabic man Character in its ethics and values. This very important thing needs a very important reaction to face that challenge to protect the cultural ARABIC & ISLAMIC characteristics and to take care of education in all its levels and forms as it is an invincible fort. For that, this field has become as the priority of the studying and researches if the
... Show MoreResearch Summary:
Seeking happiness and searching for it have been among the priorities of mankind from the beginning of his creation and will remain so until the end of this world, and even in the next life, he seeks happiness, but the difference is that a person can work in this world to obtain it, but in the next life he is expected to get what he done in this world. And among these reasons are practical actions that a person undertakes while he intends to draw close to God Almighty, so they lead him to attain his desired perfection, and to attain his goals and objectives, which is the minimum happiness in this life, and ultimate happiness after the soul separates the body, and on the day of the judgment, Amon
... Show MoreThis study came to discuss the subject of industries dependent on petrochemical industries in Iraq (plastic as a model) during the period 2005–2020, and the study concluded that the plastic industries contribute to areas of advancement and progress and opportunities to deal efficiently with the challenges posed by the new variables, the most important of which is the information revolution. communications and trade liberalization, and this is what contributes to the competitiveness of these industries. And because the petrochemical industry in Iraq has an active role in establishing plastic industrial clusters and clusters of micro, small, and medium industries by providing the necessary feedstock for these industries in various fields
... Show MoreInvestigating the strength and the relationship between the Self-organized learning strategies and self-competence among talented students was the aim of this study. To do this, the researcher employed the correlation descriptive approach, whereby a sample of (120) male and female student were selected from various Iraqi cities for the academic year 2015-2016. the researcher setup two scales based on the previous studies: one to measure the Self-organized learning strategies which consist of (47) item and the other to measure the self-competence that composed of (50) item. Both of these scales were applied on the targeted sample to collect the required data
The study deals with China's soft power and diplomacy in the Middle East, and it focuses specifically on the tools and foundations of China's soft diplomacy and how it achieves its goals in the region in addition to its challenges in the region. In this regard, the study also focuses on the Chinese Belt and Road Initiative and its soft foundations and how they serve China’s diplomacy and soft power in the region. The study ends with a set of conclusions, perhaps the most prominent of which is that diplomacy and soft power have become a fundamental pillar of China's foreign policy to achieve its foreign goals and to establish an international system compatible with China's principles. As for the Middle East, China has established a poli
... Show MoreThis research highlights one of the most important issues that have been controversial between Islamic schools, which is the duality of Intellect and Revelation and the nature of their relationship, in two core points:
The first point: Could there be a real conflict between Intellect and revelation? While the school of hadith view that this assumption is a rational assumption that does not real as long as the revelation is correct and the Intellect is clear, and that what is claimed are due to other Intellect s, we find that the Ash’ari school adopts the saying that the real conflict may occur, but rather confirms its occurrence.
The second point: For whom is the priority, for the Intellect or th
... Show MoreBackground:Oriental sore occurs mostly in the
mediteranian region , North Africa ,and the Middle East .
Rodents are the main reservoir for the parasite . The wet
type caused by L. major is rural and the dry type caused by
L. tropica is urban and humans are presumably the only
reservoir. Sand fly vectors are involved in all forms.
Objectives: This study aimed to show the most
important bacterial infections concomitant with cutaneous
leishmaniasis .
Methods; The study was performed on 75 patients (ages
1-50 years ) from both sexes were attending Skin Diseases
Department of Ramadi General Hospital during the period
extended from January to June 2000. These patients were
clinically diagnosed as patients
The aim of this research was to indicate the opinion of the Iraqi consumer awareness of the risks associated with consuming canned food, the questionnaire was included 20 questions for label information, consumer culture, shopping, marketing, awareness and knowledge as a tool to survey the opinions of 300 consumers in Baghdad, the data was analyzed by using percentage, weighted mean, and weight percent, the results obtained showed that the Iraqi consumer need more information, training and guidance programs in food safety handling issue for canned food, especially in analysis of label information and growing of consumer culture for shopping, right marketing, awareness and knowledge.
Background: Bowel preparation prior to
colonic surgery usually includes antibiotic
therapy together with mechanical bowel
preparation which may cause discomfort to the
patients, prolonged hospitalization and water
& electrolyte imbalance.
Objective: to assess whether elective colon
and rectal surgery may be safely performed
without preoperative mechanical bowel
preparation.
Method: the study includes all patients who
had elective large bowel resection at Medical
City – Baghdad Teaching Hospital between
Feb, 2007 to Jan, 2010. Emergency operations
were not included. The patients were randomly
assigned to the 2 study groups (with or without
mechanical bowel preparation.
Results: A to