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.
The: currency Auction is one of the monetary policy tools created after 2003, in order to keep pace with the changes that the monetary and financial policies will witness from financial openness and expectations of high levels of liquidity after international economic restrictions. It is necessary to re-evaluate the work of the currency Auction from time to time and observation its efficiency in adjustment the exchange rate And its reflection on the general level of prices as one of the objectives of its inception, and during the analytical aspect, it was confirmed that the currency Auction for selling the currency had a major role in adjustment the exchange rate and controlling inflation levels, due to the market’s dependence
... Show MoreAbstract
The aim of the research is to identify the effect of using the self-questioning strategy on the achievement of fourth-grade students in science and the development of their reflective thinking in physics in the city of Baghdad. The research sample was divided into two groups: an experimental group of (20) students and a control group of (20) students. The researchers developed two tools: a test of (40) multiple-choice questions. The second tool is a test to measure the reflective thinking skills of fourth-grade students. It consists of (25) multiple-choice questions distributed on skills as follow: reflection and observation, detection of inaccuracies, reaching conclusions, giving clear explanations, an
... Show MoreThe current research aims to identify: 1. The level of mathematical construct among the Department of Mathematics students in the colleges of education and basic education. 2. The level of effective mathematical operations in both sides of the brain at the Department of Mathematics students in the colleges of education and basic education. 3. The strength and direction of the correlation between the mathematical construct and effective mathematical operations on both sides of the brain at the Department of Mathematics students in the colleges of Education and Basic Education. To investigate the research objectives, the researcher formulated zero-main hypothesis for each aim and from the same hypothesis, three sub-zero hypotheses are deri
... Show MoreThe current study aimed to determine the relation between the lead levels in the blood traffic men and the nature of their traffic work in Baghdad governorate. Blood samples were collected from 10 traffic men and the age about from 20-39 year from Directorate of Traffic Al Rusafa/ Baghdad and 10 samples another control from traffic men too with age 30-49 year and they livedrelatively in the clear cities or contained of Very few traffic areas. The levels of lead in blood estimated by used Atomic Absorption Spectrometry.
The result stated that there is no rising of the levels of lead in blood of traffic men Lead concentration was with more a range from 14 ppm in Traffic police are not healthy They are within the permissible limits, Ap
The phenomenon of negative behavior has studied as a social and psychological phenomenon that effect on the performance and life of workers inside and outside the organization. The adoption of this phenomenon is studied in terms of the role of the internal environment of the organization in addressing this behavior, being the variables belong to the field of organizational behavior to see the results of those variables on the Iraqi organizations, since the specificities of it differ from the rest of the Arab and foreign environments. Therefore, this study focused on testing the relationship of the internal environment of the organization and its role in addressing the negative behavior of the workers.
thi
... Show MoreBackground and Aim: Canine parvovirus 2 (CPV-2) is a highly contagious virus that infects wild and domestic canines. Despite the use of a routine vaccination protocol, it is endemic in Iraq. The genetic drift of CPV-2 is a major issue worldwide because it abrogates virus control. In Iraq, there is a knowledge gap regarding the genetic sequences of asymptomatic and symptomatic CPV-2 cases. Therefore, this study aimed to perform a genetic analysis of viral capsid protein 1 (VP1) and viral capsid protein 2 (VP2), two major capsid-encoding genes, to demonstrate the possible role of certain mutations in triggering infection. Materials and Methods: Symptomatic and asymptomatic cases (n = 100/each) were tested by a polymerase chain reacti
... Show MoreThe objective of this study is to determine the extent to which the determinants of organizational support contributed to enhancing the mental status of banking services in a number of banks in Dohuk governorate in order to diagnose the correlation between the perceived organizational support and the mental status of services. Availability in the environment of banks and to enhance the mental position from the point of view of customers as the main hypotheses focused on the nature of the relationship between the dimensions of research among them has been tested these hypotheses using statistical and descriptive methods have been The study concluded that the contribution of organizational support, which is
... Show MoreThe second half of the last century witnessed a great scientific revolution that was able to bring about wide changes in various fields, including the field of physical education, which plays a fundamental role in the process of change for the better, and which knocked all the doors of modern science in various aspects and from this perspective we see that students have different capabilities And interests and motives, which require providing a differentiated education, and this depends on the necessity of knowing each student and on the school’s ability to know appropriate strategies for teaching each student so there is no single way to teach so the research problem comes in experimenting with an educational method that works on
... Show More
This research aims to study the impact of strategic information systems on the development of intellectual capital in the Public Shareholding Electricity Distribution Company in the Hashemite Kingdom of Jordan. To achieve the objectives of the study, a questionnaire was developed for the purpose of data collection, as the number of valid questionnaires for analysis was about (135), and SPSS and AMOS 0.26 software was used to analyze the collected data. The study found out that the respondents' perceptions of the level of importance of strategic information systems and the level of importance of intellectual capital were high, and that the relational capital has ranked as first, followed by structural capital, and h
... Show MoreIn this paper a prey-predator-scavenger food web model is proposed and studied. It is assumed that the model considered the effect of harvesting and all the species are infected by some toxicants released by some other species. The stability analysis of all possible equilibrium points is discussed. The persistence conditions of the system are established. The occurrence of local bifurcation around the equilibrium points is investigated. Numerical simulation is used and the obtained solution curves are drawn to illustrate the results of the model. Finally, the nonexistence of periodic dynamics is discussed analytically as well as numerically.