Structure type and disorder have become important questions in catalyst design, with the most active catalysts often noted to be “disordered” or “amorphous” in nature. To quantify the effects of disorder and structure type systematically, a test set of manganese(III,IV) oxides was developed and their reactivity as oxidants and catalysts tested against three substrates: methylene blue, hydrogen peroxide, and water. We find that disorder destabilizes the materialsthermodynamically, making them stronger chemical oxidantsbut not necessarily better catalysts. For the disproportionation of H2O2 and the oxidative decomposition of methylene blue, MnOx-mediated direct oxidation competes with catalytically mediated oxidation, making the most

Most companies use social media data for business. Sentiment analysis automatically gathers analyses and summarizes this type of data. Managing unstructured social media data is difficult. Noisy data is a challenge to sentiment analysis. Since over 50% of the sentiment analysis process is data pre-processing, processing big social media data is challenging too. If pre-processing is carried out correctly, data accuracy may improve. Also, sentiment analysis workflow is highly dependent. Because no pre-processing technique works well in all situations or with all data sources, choosing the most important ones is crucial. Prioritization is an excellent technique for choosing the most important ones. As one of many Multi-Criteria Decision Mak

مشكلة البحث   The Problem of the Research

          يعّد التحصيل الدراسي للطلبة عموما من أهم أركان النشاط العقلي في المجال التربوي، فلا تكاد تخلو منه أيه مدرسة، أبتداءً من المدارس الابتدائية وقد تسبقها رياض الأطفال، إلى المدرسة الإعدادية والجامعية ، وقد تمتد إلى مراحل متقدمة في العمر، فكان الطالب وما يزال هو محور العملية ال

Background: Antibiotic resistance is a problem leading to difficulty in treating microbial infections thatmay occur due to many causes. For the important pharmacist role as a reference for the information and theability to access to medications, they are vital members in lowering the development of antibiotic resistance,and also they support the proper use and control of antibioticsmisuse. Our goal is comparing the knowledge,attitude, practice of undergraduate and postgraduate pharmacy students and their perceptions about thecausing factors of antibiotic resistance in Iraq.Method: A cross sectional study was conducted involving the final year bachelor and postgraduate (masterand Philosophical doctor) students from different private

Segmented regression consists of several sections separated by different points of membership, showing the heterogeneity arising from the process of separating the segments within the research sample. This research is concerned with estimating the location of the change point between segments and estimating model parameters, and proposing a robust estimation method and compare it with some other methods that used in the segmented regression. One of the traditional methods (Muggeo method) has been used to find the maximum likelihood estimator in an iterative approach for the model and the change point as well. Moreover, a robust estimation method (IRW method) has used which depends on the use of the robust M-estimator technique in

The study aims to identify the degree of appreciation for the level of digital citizenship of a sample of Palestinian university students in the governorates of Gaza, and its relationship to the level of health awareness about the emerging coronavirus (covid-19). To achieve the objectives of the study, the researcher followed a descriptive approach by applying two questionnaires; the first, which consists of 30 items, was used  to measure the level of digital citizenship.  The second, which consists of 19 items, was used to measure the level of health awareness. Both questionnaires  were applied on a sample of 367 students who were electronically selected using the manner simple randomness. Results have shown that the degr

Transition metal complexes of Co(II) and Ni(II) with azo dye 3,5-dimethyl-2-(4-nitrophenylazo)-phenol derived from 4-nitoaniline and3,5-dimethylphenol were synthesized. Characterization of these compounds has been done on the basis of elemental analysis,electronic data, FT-IR,UV-Vis and 1 HNMR, as well as magnetic susceptibility and conductivity measurements. The nature of thecomplexes formed were studies following the mole ratio and continuous variation methods, Beer ' s law obeyed over a concentrationrange (1x10 -4 - 3x10 -4 M). High molar absorbtivity of the complex solutions were observed. From the analytical data, thestoichiomerty of the complexes has been found to be 1:2 (Metal:ligand). On the basis of physicochemical data tetrahedral