The increasing demand for energy has encouraged the development of renewable resources and environmentally benign fuel such as biodiesel. In this study, ethyl fatty esters (EFEs), a major component of biodiesel fuel, were synthesized from soybean oil using sodium ethoxide as a catalyst. By-products were glycerol and difatty acyl urea (DFAU), which has biological characteristics, as antibiotics and antifungal medications. Both EFEs and DFAU have been characterized using Fourier transform infrared (FTIR) spectroscopy, and 1H nuclear magnetic resonance (NMR) technique. The optimum conditions were studied as a function of reaction time, reactant molar ratios, catalyst percentage and the effect of organic solvents. The conversion ratio of soybean oil into pure EFEs was 76% after 10 h of reaction. The highest conversion yield of EFEs is obtained when the urea/soybean oil ratio was from 6.2 mmol to 1 mmol, while the highest production of DFAU is obtained when the ethoxide (as a catalyst)/soybean oil ratio is from 6.4 mmol to 1 mmol in hexane as the reaction medium.
A modified Leslie-Gower predator-prey model with a Beddington-DeAngelis functional response is proposed and studied. The purpose is to examine the effects of fear and quadratic fixed effort harvesting on the system's dynamic behavior. The model's qualitative properties, such as local equilibria stability, permanence, and global stability, are examined. The analysis of local bifurcation has been studied. It is discovered that the system experiences a saddle-node bifurcation at the survival equilibrium point whereas a transcritical bifurcation occurs at the boundary equilibrium point. Additionally established are the prerequisites for Hopf bifurcation existence. Finally, using MATLAB, a numerical investigation is conducted to verify t
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Problem of the research:
The studies and researches have noticed the aggravation of violence practice in all educational means using different and innovated styles against children in the school and house in order to upbringing by the parents or the school .
It is a training method for the person to participate in the society and prepare him to be an effective member.
The current research confines the children in age (6-12) years old representing the primary stage who face different kind of violence during the familiar or school education.
The current research aims to:
1 – The kinds of violence which happens to the children in the primary
... Show MoreA microbial desalination cell (MDC) is a new approach to bioelectrochemical systems. It provides a more sustainable way to electrical power production, saltwater desalination, and wastewater treatment at the same time. This study examined three operation modes of the MDC: chemical cathode, air cathode, and biocathode MDC, to give clear sight of this system's performance. The experimental work results for these three modes were recorded as power densities generation, saltwater desalination rates, and COD removal percentages. For the chemical cathode MDC, the power density was 96.8 mW/m2, the desalination rate was 84.08 ppm/hr, and the COD removal percentage was 95.94%. The air cathode MDC results were different
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Although the subject of biofuels industry is linked directly to the energy sector, but has links and numerous indirect effects, in particular effects on the environment and agriculture, this study (opportunities and challenges of biofuels industry and impact on the development of the agricultural sector in developing countries) a modest step to identify the industry in detail and identify the types of products and raw materials entering, then define or limit the positive and negative impacts of this industry in General and for specific products In particular, detailed, and then flip all those effects on the agricultural sector in developing countries can benef
... Show MoreBackground : Gastroesophageal reflux disease (GERD) is one of chronic gastrointestinal diseases in which patient may be asymptomatic or was complained from heartburn and regurgitation or pulmonary symptoms. Aim of the study : Examine the serum level of sHLA-G in GERD patients and can be used as a biomarker for early detection of GERD disease. Materials and methods : The design of the study was a case- control prospective enrolled forty patients consulted Gastroenterology Unit- Al-Kindy Teaching Hospital, were diagnosed as GERD by their physician, and compared to second forty control healthy group form January-2023 to May-2024. Serum used for quantitative assessment of soluble HLA-G (sHLA-G) using a sandwich enzyme-linked immunosorbent a
... Show MoreThe study aims to identify the uses and the impact of social networking applications and websites on stock markets and their role in defining the details of dealing with stock movement and trading. The study also aims to highlight the role of these networks by increasing confidence in stock markets and companies as well as encouraging and inciting young people to invest in these markets, the study belongs to the descriptive analytical approach, the study population consisted of all current and potential investors in the stock and financial markets in the United Arab Emirates. The study used a questionnaire that was distributed to a number of followers of social networking pages and websites that deal with trading
... Show MoreThe concept of the separation worry is considered one of the common disorders in children. The causes and effects of this worry influence the child mental and cognitive ability and the child ability to communicate with others, has friendship and the ability of adaptive with the environment, peers and teachers and it also influences the child's academic and social performance.
The importance of this study is represented in handling the working memory, one of important subject in cognitive psychology. Many universal studies show that the working memory is very important in several daily functions such as continuous attention, followinstructions, implement instructions of many steps, the moment of information remembering and keep focusin
This narrative review focused on research investigating the impact of loneliness on the prevalence of dementia and its relationship with other risk factors. A comprehensive and rigorous search was conducted using a variety of scientific databases with specific keywords to identify all prior studies that examined the correlation between dementia and loneliness. The inquiry was confined to articles published in English from January 2017 to March 2024. The narrative review identified a consensus regarding the role of loneliness in enhancing the risk of all‐cause dementia, with a particular emphasis on the subjective perception of loneliness. This phenomenon may be caused by the sensations of exclusion, discrimination, and alienation that are
... Show MoreThe Transformation of environments surrounding human which called (place), formed an intermediate compresser in forming awareness pictures, human knowledge, culture and thought features, and changing the systems and contexts of human societies, which led to a change the rhythm of life as a whole. So according to that the place will be encodes according to these data for psychological connotations, lead to human sense of harmony with the place in different manner format, here the search problem lies when trying to detect how Iraqi artist deliberating with the place concept, wondering how to investing place in the contemporary Iraqi drawing within its reference dimension, and showing mechanisms from comparative study for the works of two a
... Show MoreThe value of culture in its interaction is composed and formulated according to compatible and incompatible roles which view the identity that adopts that formation although it is in most cases perceived and declared. The attraction and difference characteristic might be implied within subjective and procedural meaning through which it seeks to make the identity mobile subject to identity- shaping cultural causes implying the conflicts that take the shape and culture of real time. As for the end of the twentieth century and afterward where the concepts of hegemony, globalization, cultural invasion, colonial and imperial culture, all these causes made the cultural identity concept appear on the surface of the critical studies as a
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