Le terme de « dureté » de l’eau correspond à sa concentration en calcium et magnésium. Plus elle en contient, plus l’eau est considérée comme "dure". Elle est mesurée par le titre hydrotimétrique (TH) dont le taux s’exprime en degrés français « °f » (1 degré français = 4 mg de calcium ou 2,4 mg de magnésium par litre d’eau). L'eau peut être plus ou moins "dure" selon les régions, cela dépend des sols que l’eau a traversés avant d’être prélevée dans la nature pour être rendue potable. Par exemple, dans les régions à sols très calcaires, l’eau sera « dure », au contraire des régions granitiques qui ont généralement des eaux « douces ». La réglementation française, pas plus que l’Union Européenne, n’ont fixé de norme sur la dureté de l'eau car elle n'est pas dangereuse pour la santé.
This project deals with the sizing of unit operations in process engineering. Process engineering is the understanding and application of the fundamental principles and laws of nature that allow us to transform raw material and energy into products that are useful to society, at an industrial level. By taking advantage of the driving forces of nature such as pressure, temperature and concentration gradients, as well as the law of conservation of mass, process engineers can develop methods to synthesize and purify large quantities of desired chemical products. In this project we will focus in the design, operation, control, optimization and intensification of chemical processes by designing pipelines in each case study. For Numerical Resolution, will use the chemical process simulator Aspen HYSYS, used to mathematically model chemical processes. We have a multitude of problems to deal with during this project. 1. Study of an incompressible fluid flow in a pipeline 2. Technology of Heat Exchangers 3. Refrigeration cycle
In this paper, an efficient enantioselective synthesis of a norbornene derivative is described. Oppolzer's chiral sultam-directed asymmetric Diels-alder [4+2] cycloaddition was conducted as a crucial tool to control the diastereoselectivity of the cycloadduct leading to the desired enantioselective target molecule after the chiral auxilary removal. The synthesis process was demonstrated as a proof of study on a lab scale and the full experiment is addressed to advanced undergraduate students who are trained in organic synthesis and NMR spectroscopy.
In this paper, an efficient enantioselective synthesis of a norbornene derivative is described. Oppolzer's chiral sultam-directed asymmetric Diels-alder [4+2] cycloaddition was conducted as a crucial tool to control the diastereoselectivity of the cycloadduct leading to the desired enantioselective target molecule after the chiral auxilary removal. The synthesis process was demonstrated as a proof of study on a lab scale and the full experiment is addressed to advanced undergraduate students who are trained in organic synthesis and NMR spectroscopy.
One of the most important grants of God Almighty to mankind is iron and other metals such as Copper. The reality thatthere is mention of copper (Cu) in the Holy Quran can be considered as a sign of it’s big importance for the human life.The fact that copper was mentioned several times either under it’s pure form or alloyed with iron might be a sign thismetal is so useful for us and without it the human civilization would not progress.Verses "Ayat” of the Holy Quran arerich in meanings and words that need to be deeply managed and checked for understanding.The interpreters have begunto explain these meanings and words for thousands of years. However, as is well known, the Qur’an has lot of secretsthat make it renewed and parallel to every age. In view of the modern scientific discoveries, many of the words of theHoly Quran have potential aspects of interpretation which are useful in understanding the purpose of these words.Therefore, most scholars have many scientific ideas and terms that explain the interpretation of the verses of the Quranand some of the Qur’anic terms from a scientific perspective that illustrates the scientific miracles in the Holy Quran.In this study we have addressed the Qur’anic word "Qitr" which was interpreted by the exponents as the dissolvedcopper in the field of Chemistry.
Le génie chimique, ou génie des procédés physico-chimiques, désigne l'application de la chimie physique à l'échelle industrielle. Elle a pour but la transformation de la matière dans un cadre industriel et consiste en la conception, le dimensionnement et le fonctionnement d'un procédé comportant une ou plusieurs transformations chimiques et/ou physiques. Les méthodes utilisées dans un laboratoire ne sont souvent pas adaptées à la production industrielle d'un point de vue économique et technique. Le génie chimique permet ainsi le passage d'une synthèse de laboratoire à un procédé industriel de même que son fonctionnement dans le respect des contraintes économiques, techniques, environnementales et de sécurité.\cite{trambouze1975developpement}Dans ce résumé de cours, vous allez trouvez l'essentiel du génie chimique pour un débutant (à l'attention des étudiants de la Deuxiéme année chimie industrielle - INSAT) ainsi que les astuces de cours pour assurer et une bonne compréhension et une bonne maîtrise de cette discipline.
In Mathematics, a differential equation is an equation that relates one or more functions and their derivatives. In applications, the functions generally represent physical quantities, the derivatives represent their rates of change, and the differential equation defines a relationship between the two. Such relations are common; therefore, differential equations play a prominent role in many disciplines including engineering, physics, economics, and biology.Mainly the study of differential equations consists of the study of their solutions, and of the properties of their solutions.Only the simplest differential equations are solvable by explicit formulas; however, many properties of solutions of a given differential equation may be determined without computing them exactly.In our report, we are interested by the resolution of two differential equations, the famous Lorenz dynamic system which was developped to understand the chaotic character of meteorology, and the Predator prey model.In the folowwing report, we are going to resolve these equations in order to understand their meanings using Matlab, but first of all, we should introduce each problem, then develop and explain both mathematical and numerical issues, our main goal is to resolve these systems with an adequate Matlab formulation, using the ode45 function and finally we should discuss the results.
Un pigment est une molécule et non une couleur. Le pigment est un élément chimique qui permetde créer une couleur, et donc une peinture ou une teinture, en le mélangeant avec un liant. Lespigments peuvent être d’origine minérale, animale ou végétale ou synthétique. Selon le type depigment employé, on obtiendra une couleur plus ou moins vive, parmi ces pigments, on cite l’indigo.L’indigo est historiquement la matière colorante bleu-violacé extraite des feuilles et des tiges del’indigotier. À partir de la fin du XIXe siècle, les chimistes montrèrent que la couleur bleu-indigoextraite de diverses plantes tinctoriales correspondait à un même pigment nommé indigotine ouindigo. Dans cet article sous forme de rapport de laboratoire, on va détailler le protocol de synthtèsede l’indigo.
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