Word came from California of a new weapon in the war on household pests．Two scientists work for a firm in California developed 1．__________ 1 t( g' H/ B# a! @5 |' l! w( ]3 |. ] a new method to eliminate insects with using dangerous chemicals．The new 2．__________ 1 `0 {+ Z0 Z! T* P weapon—hot air．The basic idea is that insect pests can adjust to temperature much above 3．__________" t; ?4 N2 u3 m& Y/ D
normal． In laboratory experiments，cockroaches and termites can’t survive much more than a quarter of hour at 100 degrees 4．__________ 6 A2 {+ U' K: x Fahrenheit or about fifty degrees centigrade． The new method involves covering a house with a huge tent，and fill it with air heated to 5．__________ * W m& |) ]2 \* L around 65 degrees centigrade．Hot air is forced in with fans and the tent keeps the heat inside the house．Although termites try to escape by 6．__________+ A# S v* e, f6 ^. Q T
hiding in wood beams，the heat treatment must be continued by four to six hours．But when it's 7．__________ : U8 ]# c* z! w! N all over and the insects are dead， there are no toxic residues to danger humans or pets，and no 8．__________/ }) k% d+ E% a
funny smells．Scientists claim that there's no danger of fire too． 9．__________ , y' m( a5 ?+ N2 M/ n t: A9 Q/ B+ S
发表于 2012-8-14 09:52:33
