Tungsten Alloy Shielding For Radiation Preservation

Radiation processing is a promising technology that has been widely applied in the processing of harvested agricultural products. Radiation preservation, which based on the radiation processing, is a method that uses ionizing radiation (mainly the γ-ray produced by radioactive isotope Co-60, Cs-137 and electron beams or X- rays generated by an electron accelerator) to irradiate fruits, vegetables and other agricultural products, making water molecules inside agricultural products interact with other substances, thereby killing microorganisms and pests, inhibiting germination and extending the shelf-life, achieving the aim of keeping fruits and vegetables in storage fresh. By 1986, 33 countries (including the former Soviet Union, the United States, Japan, etc.) approved or provisionally approved the commercialization application of 19 kinds of food products which are kept fresh by radiation. And nearly more than 20 commercial radiators have been used for radiation preservation and more than 70 kinds of food products have been allowed to extend their storage period or shelf life and kill pests or bacteria in them by radiation throughout the world.

Radiation preservation works by radiation to kill pathogenic microorganisms or harmful insects hidden in fruits and vegetables, or inhibiting their growth or causing infertility or fertility decline, thus delaying the maturation process of the fruits and vegetables to maintain freshness. Radiation preservation has the advantages of reducing losses of agricultural products, eliminating the root causes of rot and spoilage, energy saving and wide practicability. Because the γ-rays and X-rays used in radiation preservation technology have certain harm on human, and can damage the process of normal cell division leading to cancers, can cause bleeding gums, skin erythema, decreased immunity, hair loss and other diseases. Thus, related personnel should pay attention to the question about radiation protection when in dealing with fruits and vegetables and other agricultural products by radiation .Tungsten alloy shielding is the best choice.

Tungsten is a rare-nonferrous metal with high melting point, high density, high hardness and good creep resistance, thermal conductivity and electrical conductivity. While tungsten alloy is a tungsten-based alloy that adds other elements. The feature of high-density which tungsten alloy shielding has makes it has good radiation absorption and radiation shielding performance. Compared with conventional shielding materials (such as lead), tungsten alloy shielding shows the characteristics of more environmentally friendly. Lead and its compounds are toxic to human tissues, long-term use of it will lead to poisoning, but tungsten alloy shielding does not produce toxic radioactive substances, neither endanger human, nor pollute the environment. In addition, tungsten alloy shielding is easy to process, and tungsten is abundant.