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.
Zeolite Y nanoparticles were synthesized by sol - gel method. Dffirent samples using two silica sources were prepared.
Sodium metasilicate (Na2SiO3) (48% silica) and silicic acid silica (H2SiO3) (75% silica) were employed as silica
source and aluminum nitrate (Al(NO3)3.9H2O) was the aluminum source with tetrapropylammonium hydroxide
(TPAOH) as templating agent.
The synihesized-samples were characterized by X-ray diffraction, showed the requirement of diffirent aging time for
complete crystallization to be achieved. Transmission Electronic Microscope (TEM) images, showed the particles were
in the same range of 30 - 75 nm. FT-IR spectroscory, showed the synthesized samples having the zeolite Y crystal
properties. The i
Staphylococcal enterotoxin B (SEB) is a potent superantigen produced by
A biostimulant is any microorganism or substance used to enhance the efficiency of nutrition, tolerance to abiotic stress and/or quality traits of crops, depending on its contents from nutrients. Plant biostimulants like honey bee (HB) and silymarin (Sm) are a strategic trend for managing stressed crops by promoting nutritional and hormonal balance, regulating osmotic protectors, antioxidants, and genetic potential, reflecting plant growth and productivity. We applied diluted honey bee (HB) and silymarin-enriched honey bee (HB- Sm) as foliar nourishment to investigate their improving influences on growth, yield, nutritional and hormonal balance, various osmoprotectant levels, different components of antioxidant system, and genetic p
... Show MoreThe study aims to determine the organizational monitoring mechanism in target organization as well as knowing the suffocation of work. The study depends on a questionnaire as a tool of collecting data on distributed random sample involved (45) person from different levels in manufacturing isphelt Dohuk. The study depends on some hypothesis, the most significant one is that there is not impact of organizational monitoring of suffocation especially on the target organization.
This research aims at clarifying the concept of social auditing, which is one of the most important reasons for its emergence is social responsibility accounting and its role in measuring the social performance of enterprises. The study also aimed to know how social auditing has an impact and its role in improving the social performance of business organizations, and the research refers to testing the hypotheses of an impact of social auditing on social performance through a commitment to social responsibility. The research sample consisted of 200 individuals from 20 Algerian business organizations and represented individuals who were researched in managers and em
... Show MoreIraq has seen many changes at the social, economic and political levels. This led to cause many shifts in the structure of its society and imposed great challenges reflected in the behavior and awareness of that society in general and youth in particular.
Those changes made the Iraqi society undergoing the transformation of value and culture aspects formed a political awareness that caused cultural and political diversity within the family and society. A greater openness to the outside world caused by the communication revolution, as the world has witnessed during the past two decades, has helped in making that change. Iraq had its share of media and political openness, which were included after the US occupation in 2003. As a re
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This research aims to study human error effects in the banking risks in the private banks through the measurement and testing of human error effect in every kind of banking risks types and stand on the most closely associated with the risks in order to focus on them and make appropriate processors have with respect to and increase the availability of skills and expertise required to carry out banking operations of error-free manner.
Find dealt with human error in terms of meaning and understandable, classifications and types, causes and consequences and its approaches and theories. Also addressed placed banking risks in terms of meaning and concept, species and entr
... Show MoreThe study aimed to explore the school principals’ servant leadership practices for primary teachers’ perspectives in the Sultanate of Oman, furthermore to investigate the differences in those practices attributable to variables (gender, qualification, educational stage, years of experience, governorate). The study relied on the descriptive approach, by employing the survey research design using the questionnaire as a main tool for data collection, which included five dimensions of servant leadership (altruism, humility, enhancing teacher development, emotional healing, commitment to community development), Data collected from (1094) teachers in basic education schools, and they were chosen randomly. The results of the study indicated
... Show MoreThe degree of the woman’s satisfaction on clothing depends, to a large extent, on the body measurements. If clothing is very wide, it shows her enormous and if it is too tight it may draw attention to the defects of the body. It may also lead to the compatibility or incompatibility of clothing with fashion. Whatever the quality of the garment in terms of sewing and design, the costume which is not suitable for body size may affect the physical style negatively and may give the wearer an improper look. Clothing was carried out without measurements and did not use models (templates). The method of preparation affected the overall appearance because it often did not fit the shape of the body completely. Therefore, people thought in many w
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