In the present study, multi-walled carbon nanotubes (MWCNTs) with outside diameters of< 8 nm and 20−30 nm were covalently functionalized with β-Alanine using a novel synthesis procedure. The functionalization process was proved successful using Raman spectroscopy, FTIR, and TEM. Utilizing the two-step method with ultrasonication, the MWCNTs treated with β-Alanine (Ala-MWCNTs) with weight concentrations of 0.025%, 0.05%, 0.075%, and 0.1% were dispersed in distilled water to prepare water-based nanofluids. The aqueous colloidal dispersions of pristine MWCNTs were unstable. While for Ala-MWCNTs and after> 50 days from preparation, higher colloidal stability was obtained up to relative concentration of 0.955 and 0.939 for the 0.075-wt% samples of Ala-MWCNTs < 8 nm and Ala-MWCNTs 20−30 nm, respectively. The measured values of thermal conductivity were in very good agreement with the model of Nan, Birringer, Clarke and Gleiter and increased as temperature, specific surface area (SSA), and weight concentration increased, up to 14.74% for Ala- MWCNTs < 8 nm and 12.29% for Ala-MWCNTs 20−30 nm. The viscosity increased as weight concentration increased, up 25.69% for 0.1-wt% Ala-MWCNTs 20−30 nm, and decreased with the increase in temperature. Since the matching between the measured values of viscosity and the classical models of Batchelor, Brinkman, and Einstein was bad, a correlation was developed and revealed good agreement. The density and specific heat decreased as temperature increased. As weight concentration increased, the density slightly increased up to 0.065% for Ala-MWCNT < 8 nm while the specific heat decreased down to 0.95% for Ala-MWCNTs 20−30 nm, in comparison with water. The equations of (Pak and Cho) and (Xuan and Roetzel) were in good agreement with the measured values of density and specific heat, respectively. The aqueous colloidal dispersions of Ala-MWCNTs that were prepared in this work displayed robust candidature as successful substitutes for the conventional heat transfer fluids in different engineering applications for enhanced thermal performance.
Background :The incidence of bile ducts injuries( BDI )has risen from) 0.1 to 0.2%( to) 0.4 to 0.6% ( between the era of open cholecystectomy( O C) and the age of laoaroscopic cholycystectomy( LC.) The aim of the study is to review the management and surgical outcome of the bile duct injuries in gastroenterology and hepatology teaching hospital .Methods: This study is Prospective, done in G.I.T hospital ,From January 2008 –to –February 2011, patients included in this study had prevouse history of cholecystectomy which followed by sign and symptoms of bile duct injures .Most patients have been reffered from other hospitals,supprting therapy were given to them and investigations performed to evaluate the the type of injureis ,minor inj
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The current research aims to identify the role of family upbringing methods in shaping adolescent gender identity disorder, to identify the causes, components, and disorders of the gender identity of adolescents, and to develop practical visions and suggestions to reduce and stop gender identity disorder completely. Due to the sensitivity of the topic, a questionnaire of five open-ended questions was posted on Facebook to collect the needed data, where (20) respondents answered these questions. The researcher took these (20) respondents as the study sample. The results revealed that excessive emancipation within the family, failure to employ family protection laws, and failure to monitor and follow up on
... Show MoreWith the advancement of technology ,the study of cross-cultural communication via on line has become an important and researchable topic in linguistic theory and its applications.The aims of this study are two- fold (a) exploring the influence of cultural diversity on on-line interaction between American native speakers (NSs) and Iraqi non-native speakers (NNSs) of English which, together with other factors might potentially lead to what Thomas(1983) calls "pragmatic failure" (PF), a main cause of communication breakdowns and (b) specifying which type of PF occurs more frequently between the two groups along with the reasons behind such failures. To achie
... Show MoreThe traditional city suffers from the decline of the urban image due to urban development and homogeneity with the urban context of the city, and because of the lack of determinants governing the urban image, it is that the center of the city of traditional Kadhimiya suffers from a break in the urban image, Therefore, the research included how to build a distinctive urban image of the center of the traditional city of Kadhimiya and achieve the visual pleasure and comfort of the recipient and the urban image here means is an image not picture which are related to several aspects, including physical, social and psychological as well as the collective memory of individuals and their rela
The study's objective is to produce Nano Graphene Oxide (GO) before using it for batch adsorption to remove heavy metals (Cadmium Cd+2, Nickel Ni+2, and Vanadium V+5) ions from industrial wastewater. The temperature effect (20-50) °C and initial concentration effect (100-800) mg L-1 on the adsorption process were studied. A simulation aqueous solution of the ions was used to identify the adsorption isotherms, and after the experimental data was collected, the sorption process was studied kinetically and thermodynamically. The Langmuir, Freundlich, and Temkin isotherm models were used to fit the data. The results showed that Cd, Ni, and V ions on the GO adsorbing surface matched the Langmuir model with correlation coefficients (R2)
... Show MorePostmodern arguments, formed a critic case of what modernity brought in several levels. Postmodern practice was considered as a proactive case having amorphous concepts and features to what entiled as an intellectual trends postmodern philosophically and intellectually. But, what postmodernism architecture broughts in it essence, was not isolation from the intellectual context and entrepreneurship case, and it was not disconnecting from the intellectual and philosophical era of that period. Lliteratures and philosophical argument precede what (Robert Venturi) and (Charles A Jencks) had brought, albeit it was closer to critics and correction the path of modernity from crystallizing a direction that exceeds modrinity to wh
... Show MoreThis work concerns the synthesis of two types of composites based on antimony oxide named (Sb2O3):(WO3, In2O3). Thin films were fabricated using pulsed laser deposition. The compositional analysis was explored using Fourier transform infrared spectrum (FTIR), which confirms the existence of antimony, tungsten, and indium oxides in the prepared samples. The hall effect measurement showed that antimony oxide nanostructure thin films are p-type and gradually converted to n-type by the addition of tungsten oxide, while they are converted almost instantly to n-type by the addition of indium oxide. Different heterojunction solar cells were prepared from (Sb2O3:WO
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