finals rad

• Archimedes explained the reaction of solids when they are placed in liquids
• Democritus described materials as being composed of ultimate particles
• Thales discovered some of the effects of electricity
• 3 specific aspects of physical science that helped pave the way for the discovery of x-rays


  • Electricity
  • Vacuums
  • Image-recording material

  
• Evangelista Torricelli produced the 1st recognized vacuum - Barometer (1643)
• Otto van Guericke invented an air pump that was capable of removing air from a vessel or tube (1646)
• Robert Boyle is known for his law of gases. Discovered that the volume of a gas decreases with increasing pressure and vice versa—the famous Boyle's law (1659)
• Hermann Sprengel developed a type of air pump that emptied the air from a container simply by the nature of mercury (1865)
• Their techniques considerably improved the amount of evacuation, thus making better vacuum tubes available for further experimentation by other scientists
• From the 17th century forward, the main interest of scientists was the experimentation with electricity
• William Gilbert (England) was one of the 1st to study electricity and magnetism. Also noted for inventing primitive electroscope
• Robert Boyle discovered that electric force could be transmitted through a vacuum and observed attraction and repulsion
• Isaac Newton built and improved the static generator
• Charles du Fay, working with glass, silk, and paper, distinguished 2 different kinds of electricity
• Abbe Jean-Antoine Nollet made a significant improvement in the electroscope (forerunner of x-ray tube)
• Benjamin Franklin was a pioneer in electricity and conducted many electrical experiments
• William Watson demonstrated a current of electricity by transmitting electricity from a Leyden jar through wires and vacuum tube
• William Morgan noticed the difference in color of partially evacuated tubes. When a tube cracked and air leaked in, the amount of air in the tube determined the coloration
• Michael Faraday induced an electric current by moving a magnet in and out of the coil. Electromagnetic induction led to production of better generators and transformers and high voltages (1831)
• Johann Wilhelm Hittorf experimented with cathode rays -streams of electrons emitted from the cathode
• William Crookes furthered the study of cathode rays -Crookes Tube
• Philipp Lenard furthered the study of cathode rays. Cathode rays could penetrate thin metal and would project a few cm into the air

  
• William Goodspeed produced a radiograph (1890). Was not credited with the discovery of x-rays

  
• Johann Heinrich Schulze produced the 1st photographic copy of written material (1727) and discovered that silver nitrate was sensitive to light -darkened upon exposure to light in order to produce a negative image
• Richard Leach Maddox produced a film with a gelatin silver bromide emulsion (1871)
• George Eastman produced and patented roll-paper film (1884) - Eastman Kodak Company
• 1. rays


  Discovered by Wilhelm Conrad Roentgen on November 8, 1895
• Roentgen discovered x-rays while operating a Crookes tube at high voltage in a darkened room, and noticed a piece of barium platinocyanide paper on a bench several feet from the tube glowed (fluorescence)
• Roentgen submitted a report: "On a New Kind of Rays" on December 28, 1895
• Roentgen convinced his wife, Anna Bertha Roentgen (Ludwig), to place her hand on a cassette loaded with photographic plate upon which he directed the x-rays for approx. 15 mins, producing the 1st radiograph of a human - Bertha's hand, with 2 rings on her finger
• The public did not understand the principle behind x-ray production, and entrepreneurs tried to capitalize on the discovery with items such as x-ray glasses, bone portraits, and x-ray units for the home to provide entertainment for guests
• Thomas Alva Edison took notice and questioned the effects of x-rays. He complained that his eyes were sore after working with a fluorescent tube
• Serious efforts were made to protect those who worked with the rays and those who would be exposed to them. Today, a career in radiology is as safe as any career
• Michael Idvorsky Pupin produced the 1st known radiograph in the United States in 1896, and demonstrated the use of a radiographic intensifying screen (film-screen combination)

  
• Thomas Alva Edison developed the fluoroscopy - using x-ray to image the body in movement and motion, and promoted the use of calcium tungstate coating in fluoroscopy, with the hope that the vast improvement would increase sales of the Fluoroscope
• Edison also became interested in trying to develop a tube in which energy could be transformed into light rather than x-rays
• William Rollins, a Boston Dentist, used x-ray to image teeth and was a pioneer in Radiation Protection. He used a lead sheet with a hole in the center to restrict the x-ray beam (diaphragm), and a leather or aluminum filter to improve the quality of radiographs. This was the 1st application of collimator and filtration to reduce hazard in x-rays

  
• The discovery of radioactivity occurred at the same time as Roentgen's work, with certain elements emitting rays or subatomic particles spontaneously from matter
• Pierre Curie, Marie Curie, and Henri Becquerel were the three most prominent persons credited with this work and jointly awarded the Nobel Prize in Physics in 1903
• Clarence Madison Dally, an assistant of Edison, suffered severe radiation damage - burn and amputation of both arms, and died in 1904, counted as the 1st x-ray fatality in the United States