How to make pencils? Background One of the oldest and most widely used writing utensils‚ the pencil originated in pre-historic times when chalky rocks and charred sticks were used to draw on surfaces as varied as animal hides and cave walls. The Greeks and Romans used flat pieces of lead to draw faint lines on papyrus‚ but it was not until the late 1400s that the earliest direct ancestor of today’s pencil was developed. About one hundred years later graphite‚ a common mineral occurring
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Abstract This work describes the extraction of caffeine from tea leaves to determine its % caffeine. The extraction process selectively dissolves one or more compounds in a mixture into an appropriate solvent. In this experiment‚ it was visible in the process wherein the components of the tea leaves were dissolved in two solvents‚ water and dichloromethane (DCM)‚ with DCM used for multiple extractions. The organic layer was evaporated and the determined % caffeine was 0.12%. Furthermore‚ the purified
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The First Experience for a Wisdom Tooth Extraction Just a year ago‚ I got my wisdom tooth pulled for the first time. My wisdom tooth had started to ache on last New Year ‘s day. Normally‚ I celebrate New Year’s day with special food‚ but I was no time for that because of an excruciating pain. Unfortunately‚ my husband and I didn’t know a good doctor in this city‚ and we couldn’t contact friend who knows well regional information because it was a big holiday! At the long time‚ I found a dentist
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Emmanuel Ilodi‚ Ogemdi Okafor‚ etc) for going me a conducive atmosphere to carry out this research I say‚ may God bless and keep you all. Amen. ABSTRACT The extraction of pectin from orange peels has been studied at different sample to solvent ratios‚ different PHs and with different extraction techniques using water. The amount of pectin extracted reduces as the PH increased. This research work is been carried out in order to determine the process condition that will result
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Fluids The amount of fluids in the body is extremely large. There are many different forms of fluid throughout the body‚ such as blood‚ urine‚ hormones‚ cerebral spinal fluid‚ water‚ albumin‚ and bile. The fluids that make up the body are required for homeostasis. There are many different functions of body fluids such as transporting nutrients‚ waste and gases‚ transforming food into energy and generate electrical activity to power body functions. Physiologic Fluid Compartments The major fluid
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Extraction of Caffeine from Thea sinensis Abstract Extraction of Caffeine from Thea sinensis main objective is to isolate‚ purify characterized caffeine from tea leaves. Sublimation technique was used to get the % yield which is 0.07%. The melting point of the standard caffeine with the sublimate is 229°C. Introduction The active ingredient that makes tea and coffee valuable to humans is caffeine. Caffeine is an alkaloid; a class of naturally occurring compounds containing nitrogen and
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Extraction of Caffeine from Tea Leaves Introduction Caffeine is soluble in boiling water and as a result it is easily extracted from tea bags by steeping in hot water. This process leaves behind the water insoluble portions of the tea bag. However‚ water extracts more than just caffeine‚ so a final separation is done with an organic solvent that will dissolve primarily caffeine. The organic solvent used in this experiment is Dichloromethane (CH₂Cl₂). Dichloromethane is less polar than water
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Subject:Experiment # 2: Extraction and Evaporation. Separating the Components of “Panacetin” Introduction: The problem proposed in the experiment is an unknown ingredient found in generic Panacetin tablets that must be discovered. Panacetin tablets are known to contain aspirin‚ acetaminophen‚ and sucrose; therefore‚ the tablets tested‚ containing aspirin and sucrose‚ are thought to contain an unknown of something similar to that of acetaminophen such as acetanilide or phenacetin. Another problem
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Patient Case Study: Fluid & Electrolyte Imbalance This patient case study report will outline the contributing factors related to a fluid and electrolyte imbalance‚ whilst assessing the medical and nursing management for the patient. Furthermore‚ an evaluation of the implemented nursing and medical treatment will also be discussed in this report. Introduction: Patient History: Mr. Richards presented to accident and emergency on the 7th October 2004‚ primarily due to the progressive
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average person as embalming fluid is the newest drug craze that is hitting the streets in the United States. Embalming fluid’s main purpose is to slow the decomposition of the dead. Mainly found in morgues and funeral homes. The fluid involves the injection of chemicals into the body through the blood vessels for preservation of the body. The following compounds are found in embalming fluid‚ formaldehyde‚ methanol‚ and ethanol or ethyl alcohol. In embalming fluid products‚ the percentage
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