Purpose: To use the L25 Taguchi orthogonal array for optimizing the three main solvothermal parameters that affect the synthesis of metal-organic frameworks-5 (MOF-5). Methods: The L25 Taguchi methodology was used to study various parameters that affect the degree of crystallinity (DOC) of MOF-5. The parameters comprised temperature of synthesis, duration of synthesis, and ratio of the solvent, N,N-dimethyl formamide (DMF) to reactants. For each parameter, the volume of DMF was varied while keeping the weight of reactants constant. The weights of 1,4-benzodicarboxylate (BDC) and Zn(NO3)2.6H2O used were 0.390 g and 2.166 g, respectively. For each parameter investigated, five different levels were used. The MOF-5 samples were synthesized using the solvothermal reaction method, and successful synthesis was confirmed with x-ray diffraction (XRD), microscopy, Fourier transform infrared spectroscopy (FTIR) and energy-dispersive x-ray spectroscopy (EDS). The DOC obtained via XRD served as a parameter of objective quality. Results: The optimum conditions that gave the highest DOC were synthesis temperature of 130 °C, duration of 60 h, and a vehicle volume of 50 mL, with optimum Brunauer-Emmett-Teller surface area (BET -SA) of 800 m2/g. All the three synthesis parameters significantly influenced the DOC of the synthesized MOF-5 (p < 0.05). Sub-optimal conditions resulted in distorted MOFs, products that deviated from MOF-5 specifications, or MOF-5 with low DOC. Conclusion: Based on DOC and BET-SA, the best conditions for synthesis of MOF-5 when using Taguchi OA, were temperature of 130 °C, duration of 60 h, and a DMF volume of 50 mL.
This research paper is about synoptic climate specifically with in the upper air layers
using upper air layers maps analysis which are maps of thickness for the level 1000 – 500
MB, that their high average ranges between 100 – 5600 M above surface. This research paper
focuses on studying special and temporal variations of the atmosphere thickness above Iraqaccording
to this study, it is concluded that atmosphere thickness above Iraq increases
towards south with an average of 100 M as compared with north of Iraq. Regarding the
temporal variations, it is concluded that atmosphere thickness during hot months. In July, for
example, the atmosphere thickness becomes thicker than in January with an average of
(250)M
The current environment is witnessing several developments as a result of the changes taking place in all areas of economic, social , political and legal that led to the transformation of the industrial economy , which depends based on quantitative production to a knowledge economy which relies based on information and knowledge , as the central pillar of this economy during the trading of these information and knowledge between all individuals in general and decision makers , in particular, through information and communication technology of computers and the Internet to achieve sustainable human development in the social dimension. &
... Show MoreRecent studies agree that the democratic system in a country can only be established in an atmosphere of political and religious freedom. However, the term democracy and the term freedom have become controversial because their concepts remain multiple and different. Karl Popper is one of the most prominent philosophers in modern Western political thought, and one of the defenders of democracy as opposite to dictatorship. It has defined its function by its ability to restrain the ruling elite and to enforce it to prevent their tendency to tyranny. This can be achieved only in the context of the close relationship between democracy and freedom, so, if there is democracy in the absence of absolute freedom, democracy is a gateway to expandin
... Show MoreIn the theory of cinema genre, horror films are at the forefront of the list. It is one of the oldest genres that saw the light with the early emergence of cinema, taking advantage of literary works, especially Gothic literature and it continues to this day, but the third millennium has seen a marked increase in the number of films and recipients alike. There were many types within the same genre and there are many authors and varied topics, all seeking to spread terror and panic and fear in the hearts of viewers who are passionate about the type of horror. Although the fear and horror have been, throughout the ages, a challenge to the psychological balance and stability, as well as being a rejection and an opposition to the aesthetic ta
... Show MoreConstruction projects have a special nature and affect them many factors making them exposed to multiple risks as a result of the length of the implementation period and the multiplicity of stages, starting from the decision stage through implementation until the final delivery, which leads to increased uncertainty and the likelihood of risk.
The process of analysis and risk management is one of the effective and productive methods that are used in managing the construction projects for the purpose of increasing the chances of ending the project successfully in terms of cost, time and quality and at the lowest possible problems.
The research aims first to the effective planning for analysis and risk managemen
... Show MoreTwo isolates of Staphylococcus xylosus (urease producer and non urease producer) were injected in mice at a dose of 2 × 108 colony-forming units (CFU) intraurethrally. Results showed that both isolates were able to colonize kidney and bladder of the injected mice, regardless of their urease production. Moreover, there were insignificant differences between the two groups. These results emphasized the pathogenicity of this bacteria in UTI.
This research is considered a simple attempt and effort which is it first and last target is to point at the procedures of the taxes account that aims to reduce the taxes from the persons and give free to the person who estimates the tax to practice what comes from the competent authorities to describe the person who estimates the tax and not an accountant who practice the accountant procedures which are imposed on him by the annual terms from higher administrations , So he can not evaluate state of the person who pay the tax , and he might be dissatisfied with his job , because his role can’t be activated from the general foundation taxes.
And so , this research includes four fields:-
... Show MoreThe paper is concerned with a linguistic analysis of the blurbs, used in advertising English and Arabic novels. A blurb is an advertising persuasive text, written on the back cover of a book. Blurbs of selected novels are chosen as representative examples. The selected blurbs belong to two languages, Arabic and English. The paper aims at studying the linguistic features that are characteristic of blurbs as advertising texts and making a sort of comparison between English blurbs and Arabic ones. A linguistic analysis on four levels is presented. Blurbs are tackled from the point of view of four linguistic disciplines that are phonology, syntax, semantics and discourse analysis. A reference is made to the linguistic featu
... Show MoreThis research deals with the aesthetics of describing nature and the joys of urban life in the environment of Fatimid Egypt, among a group of poets, who were deceived by its enchanting beauty and breathtaking scenery, through it they depicted the reality of the life they live, and the things that involved them, as well as showing their personal culture, and the joys of life that experience, articulating this with a descriptive and analytical study, focusing on how the poet portrayed the visual scene, in an important stage of Arabic literature in Egypt.
The research aims to identify the rates of hair loss during pregnancy and lactation and its relation to the rates get some elements motivator urged through the results of the continued failure to meet the need of daily assessments of these elements, which led to the continuation of Hair Loss