X-rays (Roentgen Rays)

Discovery of X-rays:

• In 1895, German physicist Wilhelm Conrad Röntgen discovered X-rays while researching the fluorescence of materials under the influence of cathode rays.

• X-rays are produced when a beam of high-energy cathode rays (electrons) strikes a solid material.

The Nature of X-rays:

• X-rays are electromagnetic radiation with very short wavelengths, ranging from 10^-8m to 10^-11m (that is, from 10nm to 0.1nm).

• X-rays have wave properties and are similar to ultraviolet rays, but the wavelengths of X-rays are much shorter than those of ultraviolet rays.

Sources of X-rays:

• X-ray tube (Coolidge tube): This is the most commonly used device for generating X-rays. The tube consists of a cathode (negative electrode) made of a heated metal filament that emits electrons, and an anode (positive electrode) made of a high atomic number metal plate.

• When electrons are accelerated by a strong electric field between the electrodes, they collide with the anode and produce X-rays.

Properties of X-rays:

• Strong penetrating power: X-rays can penetrate materials like skin, muscle, and bone, but they are absorbed by materials with high densities, such as lead and heavy metals.

• Note: The penetrating power of X-rays depends on their wavelength and the type of material being penetrated.

• Blackening photographic film: X-rays can darken photographic film, which is why they are used in radiography to create images of the inside of the body.

• Note: The darkening effect of X-rays on film is used in radiography, but it is also a harmful effect on the body when exposed to X-rays for extended periods.

• Causing fluorescence in some substances: X-rays can cause some substances, like zinc sulfide and platinum, to glow.

• Note: The fluorescent properties of some substances are used in the construction of X-ray viewing screens.

• Ionizing air: X-rays can strip electrons from atoms, creating ions in the air.

• Note: This ionizing property is one of the factors that can harm the body when exposed to X-rays.

• Biological effects: X-rays can be harmful to the body, causing cell damage, cancer, and genetic mutations. However, at low doses, X-rays are used in medicine to treat superficial cancers.

• Note: The use of X-rays in medicine must strictly adhere to safety regulations and dosage guidelines.

Applications of X-rays:

• Radiography: Used in medicine to diagnose diseases, examine the condition of bones, teeth, and internal organs.

• Treatment of superficial cancer: X-rays are used to kill cancer cells in early stages.

• Inspection of castings, detecting air bubbles, and cracks in metals: X-rays are used to inspect the quality of industrial products.

• Airport luggage screening: X-rays are used in baggage scanners to examine passenger luggage.

Precautions When Using X-rays:

• X-rays can be harmful to the body. The use of X-rays must strictly follow safety regulations and dosage guidelines.

• People working with X-rays should wear appropriate protective gear such as lead aprons and lead glasses.

• Pregnant women should avoid exposure to X-rays.

• Exposure to X-rays should be minimized as much as possible.

Additional information:

• X-rays have also found applications in research, including crystallography, where they are used to determine the atomic structure of materials.

• X-ray technology has advanced significantly, leading to the development of digital radiography and computed tomography (CT) scans, which provide more detailed and precise images.

• The safety of X-ray use is continuously monitored and evaluated by health authorities and regulatory bodies.