Nuclear medicine is a field of medicine that uses radioactive substances to diagnose and treat injuries and diseases, and also to understand how the body works.
Nuclear medicine is a field of medicine that uses radioactive substances to diagnose and treat injuries and diseases, and also to understand how the body works. Radioisotopes give doctors the ability to look inside the body and observe soft tissues and organs in a manner similar to x-rays. Many radioactive materials used in nuclear medicine are gamma ray emitters - such as Iodine 131 and Technetium 99m, used for their penetrating abilities and low ionising ability. However, when ionisation of cells is required - for example, when treating some cancers, alpha emitters are often used. The basis of nuclear medicine was discovered 100 years ago. Famous personalities such as Alexander Graham Bell suggested placing radioactive sources near tumours to treat them, and as early as 1905, radiation was used to treat thyroid disease. The 20s and 30s were times of rapid development in nuclear medicine. Radioactive phosphorus was given to animals, and their metabolic processes studied. Phosphorus-32 was also used to treat a leukaemia patient. In 1938, technetium-99m was discovered. This radionuclide has become the basis for nuclear medicine. Because of its short 6 hour half life, low radiation dose and chemically reactive nature, it was thought to be ideal for human imaging, and is used today in about 90 percent of nuclear medicine procedures. In the 1940s and 50s, medical cyclotrons
Electromagnetic Spectrum.
Project on Electromagnetic Spectrum The electromagnetic spectrum is made up of electromagnetic waves such as light, radio waves and infrared. Although they travel at the same speed the frequency and wavelengths of each group is different. Although they travel at the same speed, the frequency and wavelengths of each group is different. The electromagnetic waves are usually split into seven basic types: Radio Waves - 1m-104m. Micro Waves - 10 m (3cm) Infra Red - 10 m (0.01m) Visible Light - 10 m Ultra Violet - 10 m X-Rays - 10 m Gamma Rays - 10 m Region in the Electromagnetic Spectrum:- Microwaves Uses in Domestic Situation:- Microwaves are uses in cooking of food; water molecules absorb the microwaves after they are passed easily into the food. Dangers in domestic situations:- Microwaves can also be absorbed by living tissue, therefore, making them dangerous. The heat can then damage or kill the cells, causing a "Cold Burn". Region of Electromagnetic Spectrum:- Infrared Uses in Domestic Situations:- Infrared is used for all remote controls of TVs and videos. It's ideal for sending harmless signals over short distances, without interfering with the other radio frequencies. They're also used in toasters to heat the bread. Dangers in domestic situations:- Over-exposure to infrared causes damage to cells, like Microwaves. It's this over-exposure that
are moblie phone safe
Contents : Page 1 : Title Page And Introduction Page 2 : What Are Possible Risk Of Using Mobile Phones? Page 3 : What Is In A Mobile? And Electro Spectrum Page 4 : Ionizing and non-Ionizing radiation Page 5 : Tumors And Further Information on Radiation, can mobile phones cause tumors Page 6 : Symptoms and treatments of tumors Page 7 : Are Children More At Risk? Advice About Using Your Mobile. And Conclusion Page 8 : Conclusion and Bibliography What Are The Possible Risks Of Using A Mobile Phone? What are the possible risks? There are fears that the electromagnetic radiation emitted from mobile phone handsets may harm health. In particular, there have been claims that it could affect the body's cells, brain or immune system and increase the risk of developing a range of diseases from cancer to Alzheimer's. While there is no evidence to back up these fears, laboratory tests on mice have shown that radiation from mobile phones can have an adverse effect on their overall health. It is still not clear whether those findings can be applied directly to humans. A study by scientists in Finland, published in 2002, suggested that the electromagnetic radiation did affect human brain tissue. But they played down their findings saying more research was needed to see if the effects were the same in living people. Another study by scientists in Sweden, also
ELEMENTS PROJECT:FLOURINE
ELEMENTS PROJECT:FLOURINE PROPERTIES: Element : Flourine Symbol : Capital F Atomic Number : 9 Atomic weight: 18.9984032(18.99) Registry ID: 7782-41-4 Group number: 17 Group name: Halogen Period number: 2 Block: p-block Melting Point: -219.62C Boiling Point: -188.14C Standard State: GAS Number of Protons/Electrons in Fluorine : 9 THE PICTURE IS THE ATOMIC STRUCTURE OF FLOURINE Number of Neutrons in Fluorine : 10 COLOR:Yellow but pale Definition of the Fluorine Element A pale-yellow, highly corrosive, poisonous, gaseous halogen element, the most electronegative and most reactive of all the elements, used in a wide variety of industrially important compounds. Origin / Meaning of the name Fluorine The name originates from the Latin word 'fluo' meaning flow. Classification of the Fluorine Element Fluorine is classified as an element in the 'Halogens' section which can be located in group 7 of the Periodic Table. The term "halogen" means "salt-former" and compounds containing halogens are called "salts". The halogens exist, at room temperature, in all three states of matter - Gases such as Fluorine & Chlorine, Solids such as Iodine and Astatine and Liquid as in Bromine. Facts about the Discovery and History of the Fluorine Element First described in 1529 by Georigius Agricola for its use as a flux. Fluorine was discovered by Joseph Henri Moissan in
What is Spectroscopy?
What is Spectroscopy? Spectroscopy is the study of energy levels in atoms or molecules, using absorbed or emitted electromagnetic radiation. There are many categories of spectroscopy eg. Atomic and infrared spectroscopy, which have numerous uses and are essential in the world of science. When investigating spectroscopy four parameters have to be considered; spectral range, spectral bandwidth, spectral sampling and signal-to-noise ratio, as they describe the capability of a spectrometer. In the world of spectroscopy there are many employment and educational opportunities as the interest in spectroscopy and related products is increasing. However Spectroscopy is not a recent development, as it has been utilized for many years since Isaac Newton made the first advances in 1666. Spectroscopy is the study of light as a function of wavelength that has been emitted, reflected or scattered from a solid, liquid, or gas. Fundamentals of Spectroscopy Spectroscopy is the distribution of electromagnetic energy as a function of wavelength. Spectrum is basically white light dispersed by a prism to produce a rainbow of colours; the rainbow is the spectrum of sunlight refracted through raindrops. All objects with temperatures above absolute zero emit electromagnetic radiation by virtue of their warmth alone; this radiation is emitted at increasingly shorter wavelengths as temperature is
AIM OF EXPERIMENT: TO DETERMINE THE RATE OF REACTION OF HALOGENOALKANES
AIM OF EXPERIMENT: TO DETERMINE THE RATE OF REACTION OF HALOGENOALKANES EQUIPMENTS REQUIRED * Eye protection * Marking pens or labels * A test tube rack and 6 test tubes * Beaker ( 250cm3) * Bunsen burner, tripod stand * Measuring cylinder (10cm3) * Thermometer ( 0oC-100oC) * Stop clock * Source of laser light. * 1-bromobutane* * 1-chlorobutane # * 1-iodobutane* * Silver nitrate solution (0.1mol dm-3) * Ethanol# * Dropping pipettes : 1 for each bottle * Source of hot water * Harmful. Eye protection must be worn # Highly inflammable. Keep tubes and bottles away from naked flame. INTRODUCTION A halogenoalkane is a compound which has a carbon (C) - halogen(X) bond in its carbon chain. The C?+? X?-bond is polarised due to the difference in electro negativity between the carbon atom and the halogen atom. This induces the slightly positive charge on the carbon atom and the slightly negative charge on the halogen atom. The slightly positive charge on the carbon atom makes it open to nucleophilic attack. This results in the displacement of the halide ion. This experiment will compare the rate of hydrolysis of 1-chlorobutane, 1-bromobutane and 1-iodobutane where H2O acts as a nucleophile. METHOD: ) Fill a two-thirds of a beaker with water and insert a thermometer into the beaker 2) Heat water in a beaker till it reaches about 50oC 3) Put 1 cm3 of 0.1mol
Radiation - uses and dangers
Treating Cancer Because Gamma rays have the ability to kill any living cell, they are used to kill cancer cells. This is called radiotherapy. It works because cancer cells cannot repair themselves when damaged by gamma rays, whereas healthy cells can. It's vital to get the dose correct, as if there is too much you will damage more healthy cells. However, too little and you won't kill the cancer. Some types of cancer are easier to treat with radiotherapy than others. It's not very difficult to aim the gamma rays at a breast tumour, although with lung cancer it is harder to avoid damaging many healthy cells. Also, lungs can be more easily damaged by gamma rays, therefore different treatments would be advised. Sterilising Gamma rays are used in hospitals to sterilise equipment. Normally equipment is sterilized using heat, but heat would damage some objects like syringes. Gamma rays are used to kill bacteria, mould and any possible living insects in the food. It also preserves the food so that it can remain on the shop's shelf for longer. However, it can have it's affects and can change the taste of the food. Dating Animals and plants have a known proportion of Carbon-14 (a radioisotope of Carbon) in their tissues. When they die they stop taking Carbon in, then the amount of Carbon-14 goes down at a known rate (Carbon-14 has a half-life of 5700 years). The age of
Ultraviolet radiation and skin cancer
ULTRAVIOLET RADIATION AND SKIN CANCER Skin cancer is the most common malignancy in humans and accounts for one third of newly diagnosed cancers. It is estimated that skin cancer will be diagnosed in around 1 in 5 Americans during their lifetime and more than 1 million cases are diagnosed each year [1]. Ultraviolet light from the Sun is the main cause of skin cancer and plays a major role in the 2-3 million non-melanoma skin cancers and 132,000 malignant melanomas that occur annually. The incidences of skin cancer are becoming more and more common, causing global concern. There could be many reasons for this. For example, people are living longer and so their lifetime sun exposure is increased. They also have more money to spend on outdoor activities and holidays in sunny climates. Many still feel that suntans are healthy and attractive and therefore deliberately expose themselves to the sun and consequently to UV radiation [2]. Due to the causal link between UV light and skin cancer, its prevention and protection against this type of radiation has been at the forefront of a lot of research done by companies such as the World Health Organisation. They have set up a scheme called INTERSUN, a 'global UV project'. This project promotes research activities that aim to fill in gaps in knowledge and quantifies the health risks of UV exposure [3]. Everyone is exposed to UV
Rutherford’s Alpha-Particle Scattering Experiment
Rutherford's Alpha-Particle Scattering Experiment Early Views of the Atom i. Around 400 BC a Greek scientist called Democritus said that matter was made up of small particles he named 'Atoma' (meaning indivisible). ii. In 1804 John Dalton stated that matter consisted of tiny solid balls he called 'Atoms'. Backdrop of Rutherford's Experiment At the turn of the century, there was little known about atoms except that they contained electrons. J. J. Thompson discovered the electron in 1897, and there was considerable speculation about where these negatively charged particles existed in nature. Matter is electrically neutral; some positive charge must balance the charge of the electron. These was what the scientist thought at that time. One popular theory of the time was called the 'plum-pudding model'. This model, invented by Thompson, envisioned matter made of atoms that were spheres of positive charge spiked with electrons throughout. Electrons were chunks of plum distributed through a positively charged sphere of pudding. The Experiment The 'plum-pudding model' was accepted until the famous experiment - Rutherford's alpha particle scattering experiment' was carried out. Actually, the two students of Rutherford -Geiger and Marsden were asked to carry it out. They fired a sheet of gold foil by the alpha particles. The alpha particles were emitted from a sample of
Solar Cell
Experiment to investigate how the output voltage from a solar panel varies as the light intensity varies. Solar cells transferred light energy into electrical energy. Apparatus :- Lamp Ruler Multi-meter Solar panel Red and black wires As part as my investigation, I am going to measure the output voltage form the solar panel. The range we need to use is 200mV, to see if the mill volts output varies with the distance. MV stands for mill-volts; a mill-volt is 1/1000 of a volt. At first you place the meter ruler and follow on by placing the lamp at the end of the ruler where is shows '0'. To connect both black and red leads from the solar cell to the multi-meter. You the place the solar cell on top of the ruler at 100mm and record the reading in mV. You carry on the experiment by doing the same every 100mm, e.g. 200mm, 300mm etc. this will continue until I reach 1000mm as the ruler is a meter long. I will do this 3 times as trial but will also record the reading. This is to be more accurate in my experiment and if the results aren't the same then I will work out the average to get my final record. The rules for my experiment is so keep the same lamp in the same place and to make sure that there is the same amount of darkness every time I take the reading. My prediction is that the further I will take the solar panel away from the lamp the less the reading of the
