rubber made of certain kinds of hydrocarbons.
Of these butadiene is the most important.
These hydrocarbons are obtained from coal,
crude petroleum and alcohol. By the end
of the Second World War, the combined production
of synthetic rubber by Synthetic rubber
is more oil resistant than natural rubber.
In the international market, natural rubber
is facing severe competition from synthetic
Slam is a sports term pertaining to a group
of matches, Championships etc. in a particular
sports and the winning of all these matches.
The best known Grand Slams are those in
Tennis [the Australian Open, the French
Open, the British Open, the French Open,
Wimbledon, and the US Open], Golf [the US
Open, the British Open, the Masters, and
the PGA], and Rugby Union [victories against
all opposition in the competition between
England Wales, France, Ireland and Scotland].
1816, the French physician Rene Theoplhie
Laennec (1781-1826) introduced a perforated
wooden cylinder which concentrated the sounds
of air flowing in and out of the lungs,
and described the sound which it revealed.
The modern form of stethoscope, with flexible
tubes connecting the earpieces to a circular
piece placed against the chest, was developed
later in the nineteenth century.
is the world’s leading producer of
sheet mica and accounts for about 60 percent
of global mica trade. Important mica bearing
pegmatite occurs in Andhra Pradesh, Bihar,
Gujarat, Hariyana, Karnataka, Kerala, Maharashtra,
Orissa, Rajasthan, Tamil Nadu and West Bengal.
little of “The Land of the Rising
Sun” is a form of Japan’s indigenous
name of Nippon, which literally means “sun
origin”. The allusion is to the geographical
location of Japan with regard to China.
The Japanese flag shows the sun’s
red on a white background.
to the Guinness Book of Records 1999, Angkor
Wat (“City Temple”) in Cambodia
is the largest religious structure ever
built, covering an area of 402 acres. The
entire temple complex has a total area of
15 by 5 miles and consists of 72 major monuments,
the construction of which began in AD 900.
the case of lower animals, there is a whole
succession of teeth throughout their lives.
As their teeth are fully developed and used
up, they fall out and new ones take their
place. Only man has a single replacement
of his teeth. By the time a baby is about
two years old, it has total of 20 teeth,
called milk teeth. Beneath these milk teeth,
there is second series of teeth that begin
to appear after the ago of six. The milk
teeth are replaced by about the age of twelve
and then more teeth appear until the adult
finally has his no more chance of having
new teeth, he has to keep them healthy and
free from decay.
It is enamel of the teeth that becomes vulnerable
to decay. For instance, when there is an
invisible opening in the enamel, the bacteria
in our mouth try to sneak into the cavity
and they feed on the juicy dentine and the
lymph that is in the dentine canals. Soon
they erode the walls of the canals, and
a cavity is created beneath the enamel.
This may go unnoticed for some time, but
if the wall of the teeth becomes thin as
a result of the work of the bacteria, then
we notice it very quickly, just because
heat and cold can now penetrate more strongly
to the pulp cavity. The pulp occupies a
hollow space in the centre of the tooth
and contains nerves. These nerves are stimulated
by the heat or cold. When a tooth feels
sensitive to heat or cold, you can be pretty
sure it is a danger signal that decay is
When the bacteria penetrate through the
dentine canals into the pulp cavity, they
find a perfect feeding and breeding ground.
Now you are in for a toothache as the decay
of the tooth has already set in and the
network of vessels that supply food to the
teeth withers away. The tooth that is no
longer nourished becomes a dead shell.
Ikebana pertains to Japanese floral art
or flower arrangement. It is a highly elaborate
and unique form with highly developed conventions
and complex symbolism. People say that Ikebana
is associated with the ritual of offering
flowers to the Buddha.