Evolution of Skin Pigmentation due to UV Levels and Genes Introduction Identification of a person has long been related to the color of their skin‚ as skin color is the defining measure of races. There are multiple variations in skin color throughout the globe‚ with the differences in outward appearance ranging from dark to light. But what exactly has caused this to occur? What is the underlying event that has led to so much variation in the pigmentation of a person? What selection pressures
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Lesson 2 History Of Refrigeration – Development Of Refrigerants And Compressors 1 Version 1 ME‚ IIT Kharagpur The objectives of the present lesson are to introduce the student to the history of refrigeration in terms of: 1. Refrigerant development (Section 2.2): i. ii. iii. Early refrigerants (Section 2.2.1) Synthetic fluorocarbon based refrigerants (Section 2.2.2) Non-ozone depleting refrigerants (Section 2.2.3) 2. Compressor development (Section 2.3): i. ii. iii. iv. v. vi. Low-speed
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BEDBUGS: PUBLIC HEALTH IMPORTANCE 237 CHAPTER 4 Bedbugs‚ fleas‚ lice‚ ticks and mites Ectoparasites that live on the body‚ in clothing and in beds There are many different species of bloodsucking fleas‚ lice‚ ticks and mites. Lice live on humans or in their clothing‚ while fleas are frequently found taking bloodmeals on people and domestic animals. Bedbugs‚ which can be found in beds or furniture‚ feed on humans to obtain blood-meals. Some mites live in people’s skin‚ e.g. the mites that
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carbonate with methanol to give dimethyl carbonate and ethylene glycol is described in a Texaco patent; a general description of the chemistry has also been published. Selectivity to ethylene glycol are excellent with little Diethylene glycol or higher glycols produced. A wide range of catalysts may be employed including ion exchange resins‚ zirconium and titanium compounds‚ tin compounds‚ phosphines‚ acids and bases. The process produces a large quantity of dimethyl carbonate which would require
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Laboratory Experiment pubs.acs.org/jchemeduc NMR Kinetics of the SN2 Reaction between BuBr and I−: An Introductory Organic Chemistry Laboratory Exercise T. Andrew Mobley* Department of Chemistry‚ Grinnell College‚ Grinnell‚ Iowa 50112‚ United States S Supporting Information * ABSTRACT: A simple organic chemistry experiment is described that investigates the kinetics of the reaction between 1-bromobutane (BuBr) and iodide (I−) as followed by observing the disappearance of BuBr and the appearance
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Vol. 1 ACETIC ACID 115 ACETIC ACID 1. Introduction Acetic acid [64-19-7]‚ CH3COOH‚ is a corrosive organic acid having a sharp odor‚ burning taste‚ and pernicious blistering properties. It is found in ocean water‚ oilfield brines‚ rain‚ and at trace concentrations in many plant and animal liquids. It is central to all biological energy pathways. Fermentation of fruit and vegetable juices yields 2–12% acetic acid solutions‚ usually called vinegar (qv). Any sugar-containing sap or juice can
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THE BIOSPHERE The environment (biosphere) extends to about 20 km from the bottom of the ocean to the highest point in the atmosphere at which life can survive without manmade protective devices. Biosphere contains about 1.8 million known species. The essential requisites of life for all life forms (light‚ heat‚ water‚ food‚ and habitats) are supplied by the biosphere. Biosphere is very complex and large‚ so it is divided into smaller units (ecosystems). Each ecosystem consists of two parts: biotic
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DRIED MALUNGGAY (Moringa oleifera) LEAVES IN ETHANOL PRODUCTION A Research Proposal Presented to Carmona National High School Special Science Curriculum In Partial Fulfillment of the Requirements for Research I Proponents: Catangay‚ Jhantal A. Gicana‚ Emchie Elaine R. Marasigan‚ Jan Ian B. Natividad‚ Abigail Jacinthe B. Viaje‚ Kyrinne Kate M. Zara‚ Hazel Jane Muriel C. March 2012 CHAPTER 1 THE PROBLEM AND ITS BACKGROUND We all know that ethanol or ethyl alcohol has a very
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BACHELOR OF SCIENCE (HONS) BIOTECHNOLOGY YEAR 1 SEMESTER 1‚ 2 & 3 UDBB 1164 FUNDAMENTAL ORGANIC CHEMISTRY 0 EXPERIMENT 1 PROPERTIES OF HYDROCARBONS Introduction Hydrocarbons are compounds which contain only carbon and hydrogen‚ can be classified into several types‚ depending on their structure. Aliphatic hydrocarbons are divided into three classes: alkanes (e.g. methane‚ ethane and propane) have only single bonds‚ and are said to be saturated; alkenes (e.g. ethene and propene)
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INTRODUCTION In the diet of every nation‚ milk is considered as nature’s perfect food. The consumption of milk and its food products have been increased as a sign of prosperity. The growing underdeveloped countries in the last few decades have adopted milk and its food products in their diets. Milk can be defined as the fresh and clear lacteal secretion practically free from colostrums and obtained by the complete milking of one or more milky animals like cow‚ buffalo‚ goat etc. In human
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