时间:2018-12-01 作者:英语课 分类:VOA2003(下)-发展与科学


英语课


By Gary Garriott


Broadcast: November 3, 2003


This is Steve Ember with the VOA Special English Development Report.
People have been recycling metals for hundreds of years. Today, re-using metal waste or 1)scrap 1 provides work for many people, especially in developing countries. Three kinds of metals are recycled. They are 2)ferrous metals, non-ferrous metals and precious metals.
Ferrous metals contain iron. They are low in cost and recycled in huge amounts. Metallic 2 iron called pig iron is produced when iron is heated in a hot industrial stove. This kind of stove is called a blast 3)furnace. Pig iron also contains another element, carbon. Pig iron is useful because it can be formed into solid, heavy objects or objects with unusual shapes.
Another kind of iron is steel, which is iron without the carbon. Making steel is simply removing the carbon by burning it away. This makes the steel stronger and easier to cut than iron. Both pig iron and steel waste or scrap are useful because they can be melted to make new products.
In countries where there is a shortage of steel scrap, old 4)tin cans are sometimes used and melted. Tin cans are mostly steel. If the scrap is heated before the temperature gets to the melting point, the blast furnace can be more simply designed and less costly 3. These simpler furnaces are called 5)foundries. Products are made in foundries all over the world, but especially in Asia.
Non-ferrous metals include copper 4 and 6)aluminum 5. Copper is the perfect material for recycling. It is valuable, easy to identify and easy to clean. People who operate foundries around the world buy copper wire and cable to recycle.
Aluminum is another very popular non-ferrous scrap metal. It is cheap to produce and very easy to work with. In developing countries, small foundries produce aluminum bars, sheets and wire.
Precious metals like silver also are recycled. Silver can be found in pictures made with an old black-and-white camera. And it can be found in X-rays after they have been developed. X-ray film is very valuable for recycling silver, because both sides of the film are usually developed.
You can learn more about recycling metals from Volunteers in Technical Assistance, or VITA. VITA is on the Internet at vita.org.
This VOA Special English Development Report was written by Gary Garriott. This is Steve Ember.


注释:
1) scrap [skrAp] n.残余物,废料
2) ferrous [5ferEs] adj.铁的,含铁的
3) furnace [5fE:nis] n.炉子,熔炉
4) tin [tin] n.锡
5) foundry [5faundri] n.铸造
6) aluminum [E5lju:minEm] n.铝



1 scrap
n.碎片;废料;v.废弃,报废
  • A man comes round regularly collecting scrap.有个男人定时来收废品。
  • Sell that car for scrap.把那辆汽车当残品卖了吧。
2 metallic
adj.金属的;金属制的;含金属的;产金属的;像金属的
  • A sharp metallic note coming from the outside frightened me.外面传来尖锐铿锵的声音吓了我一跳。
  • He picked up a metallic ring last night.昨夜他捡了一个金属戒指。
3 costly
adj.昂贵的,价值高的,豪华的
  • It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
  • This dictionary is very useful,only it is a bit costly.这本词典很有用,左不过贵了些。
4 copper
n.铜;铜币;铜器;adj.铜(制)的;(紫)铜色的
  • The students are asked to prove the purity of copper.要求学生们检验铜的纯度。
  • Copper is a good medium for the conduction of heat and electricity.铜是热和电的良导体。
5 aluminum
n.(aluminium)铝
  • The aluminum sheets cannot be too much thicker than 0.04 inches.铝板厚度不能超过0.04英寸。
  • During the launch phase,it would ride in a protective aluminum shell.在发射阶段,它盛在一只保护的铝壳里。
学英语单词
?-bebeerine
Aethusa cynapium
aminobenzamide
amiprophos-methyl
an ad balloon
anthraces
asymmetric input/output
asymptotically equivalent
balance cock rest
bipartile
boning knife
Bou Ali
c.a.a.
campo mourao
CCO2
Chen Shigong
Cisternino
click into place
communication oriental real-time executive
commutator room
compression method
cottars
database package
differential coherent
dipterous insect
dispersal error
escapement-wheel
expulsion tube
feerite modulator
fibroendothelioma
finucane
fissiler
forktails
freqency cutoff
full-antomatic buret
generalisers
Guest, Edgar A
heat labile antibody
heavy aromatics
heavy-loaded plain bearing
iced out
indoor insulator
integrating element
intermittent ballistic test
japhets
Knoxia
lateral gradient
launch site for manned space flight
leave open
lithacrosiphon cristatus
long-and short-term objectives
mandatory redemption
maximum working hours
motor luggage van
multigeneration
naval attache
neutral grip
nuclear pumping laser
O2-uptake
offer of partial acceptance
oh-h-h-h
oil carrier
oilpresser
orthoiodohippurate
Otto Hahn
patou
personates
porphyromonas
prediction error covariance
pseudocercospora angulomaculae
PSOs
Pterophoridae
racontage
radwaste hopper
reheat stage
roll back policy
rose-tinged
run-time supervisor
Sahul Banks
sap rate
secondary affective insanity
shovels
signal amplitude
silver certificate
snowperson
Some-sex marriage
spaghettification
starter condenser
station auxiliary generator
subtendinous synovial bursa
televisuals
telok
theoretical and empirical analysis
travel package
triggering
turrethead
Turuntayevo
vocabs
water-collapsible loess-soil
wild indigoes
win-win-win situation
yoshiki