INTRODUCTION Analysis of Caffeine in Beverages by HPLC Essay

INTRODUCTION Analysis of Caffeine in Beverages by HPLC - Essay Example It is also addictive and the prevalence of caffeine in many drinks available today is a growing, serious health concern because it is a stimulant (Bidlingmeyer 385). The amount of caffeine present in soft drinks like Pepsi and Mountain Dew can be determined by the use high-performance liquid chromatography (HPLC). This is a process by which a mixture can be separated into its separate components or ingredients by the use of laboratory technique called as chromatography. In this process, the mixture to be separated is dissolved in a liquid, then it is passed or flushed through a stationary material (called as bed) and separated due to different rates of absorption of different materials. It is used to separate complex compounds with high precision using the right adsorbent materials and carrier fluid. A can (12 oz.) of Pepsi has about 38 mg (milligrams) in it while a Pepsi Max has about 69 mg. A can of Mountain Dew (both regular and diet) has approximately 54 mg of caffeine (Center for Science in the Public Interest para 2). Instant coffee has 65 mg, espresso has about 80 mg while Turkish coffee has one of the highest at about 160 mg. HPLC is sim ply an improved version of column chromatography that used gravity to force separation but in HPLC, the process is made faster by using high pressure at up to 400 atmospheric

Don't change it Essay Example | Topics and Well Written Essays - 1000 words - 2

Don't change it - Essay Example While other philosophers like Rousseau opposed this crucial view of humans by viewing them as cooperative, selfishness and fear are the main reasons why humans harm each other (Rousseau, paragraph 12). Shifting from the evil human image that Hobbes explained, to the well-disposed human image of Rousseau, makes an obvious antagonism between both philosophers. Indeed, both Hobbes and Rousseau wrote about the same points, which are human nature, social contract, and the form of government, but each of them had different explanations to these ideas. In the idea of human nature, Hobbes started by explaining his idea through arguing that all men are created equal in their aptitude and wish (Hobbes 57). Indeed, Hobbes indicates that no man is above other men, but what make men different are sciences and the amount of knowledge that each person carries (Hobbes 59). Even though each man has a different amount of knowledge, a man in his nature always sees himself better than others and do not like to admit that other men are better than him (Hobbes 59). Rousseau illustrated that men are equal but they are different from each other based on two facts, which are their physical features such as their age, way of looking and the soul, which is mainly about human behavior and morals (Rousseau, paragraph 1). In addition, Rousseau views all men as free and this is evident when he argues that though man was born without any restrictions, everywhere he goes he is in chains. (Rousseau 81). The Chains Rousseau means in his writing are the restr ictions and the power the government puts on men’s freedom (Rousseau 81). Rousseau also believes that power is not created by nature but it is created by God’s wish. In other words, God is the one who choose specific people to give them power similar to the relationship between a parent and his or her child (Rousseau, paragraph 4, 10). Moving to the idea of conflict and competition, according to