Техническое чтение для энергетиков. Бухарова Г.П. - 5 стр.

UptoLike

ВУЗ: 

УлГТУ | Ульяновск

Составители: 

Рубрика: 

7
THE NATURE OF THE ATOM
All the prime movers, natural and man-made, which, humanity has harnessed to
ease its burden of labour and raise its standard of living are, in fact, attempts at
utilizing the energy of the sun: it sustains organic life on earth with its light and heat,
it makes the water circulate between the heavens and the sea, it creates the wind, and
it has filled for us a vast storehouse of coal and oil, the mineral deposits from old
ages of vegetation. What our inventors did when they built power-producing engines
was to change one form of energy–such as the heat of burning coal – into another, the
mechanical energy of rotating wheels or the light of an electric lamp. They could not
create energy from nothing; they could only release it by some chemical process.
This means that although the molecules, or combinations of atoms, may break up and
form new combinations, the atoms themselves remain intact and unchanged.
There is one source of energy, however, which owes nothing to the heat and
light of the sun; nor can it be harnessed by a chemical process. It is the energy of the
atomic nucleus.
The term 'atom', coined by the Greek philosopher Democritus about 2,500
years ago, is rather misleading. It means 'the indivisible', and it is a relic from the
times when people believed that all matter consisted of very small particles which
were Unchangeable and indivisible, and that each element had its own special kind
of particles. Only the medieval alchemists hoped that they could, by some magic,
change the particles of one element into those of another – lead, for instance, into
gold.
Today we know that atoms are neither unchangeable nor indivisable. The story
of research into the nature of the atom has been told many times. It may be sufficient
to recall that Marie and Pierre Curie, by their discovery of radium, in 1898, made the
whole theory of the indivisible atom crumble, because here was an element which
disintegrated and sent out rays, consisting of particles much smaller than the atom.
Another discovery, made three years earlier, seemed to point in the same
direction: that of the X-rays by Professor Wilhelm Konrad Rontgen at the University
of Bavaria. Using a cathode-ray tube, he found that the radiation emanating from it
was able to penetrate thin matter like wood and human flesh, but was stopped by
thicker objects such as pieces of metal and bones. It was only later that the nature of
these mysterious rays was discovered: particles of negative electricity, called
electrons, turn into electro-magnetic waves, of the same kind as light but of shorter
wave-length and therefore invisible, when they strike a material object such as a
metal shield in the cathode-ray tube.
These and other phenomena and discoveries around the turn of the century
were deeply disturbing for the physicists, and they saw that the whole traditional
concept of the structure of matter had to be completely revised More than that: the
borderline between matter and energy seemed to disappear. When, as early as 1905,
Albert Einstein published his Special Theory of Relativity, in which he declared that

Страницы