Around the sun leaving a bright trail behind. For more than

as well as	hem ... hem de ...kadar iyi:	move out
1. evden taşınmak.2. dışarı çıkmak.
automate	otomatikleştirmek, makineleştirmek.	nutrient	besleyici, besinli; gıdalı
chance	talih, şans; kader	ordinary	sıradan, alelade olağan
Consist of	-den meydana gelmek, -den oluşmak	resistant	direnen, karşı koyan.dirençli.
cucumber	hıyar, salatalık	sense	duygu, duyu algılamak
delivery	teslim; dağıtım. doğurma; doğum.	thought	düşünce, fikir, tasavvur
determine	karar vermek, azmetmek; niyet lenmek	through	Vasıtasiyle, yolu ile. boyunca: içinden
device	cihaz, aygıt, alet	transparent	şeffaf, berrak, saydam cam gibi
dissolve	eritmek; erimek. çözmek	turn off	kapamak. kesmek.
expand	genişletmek büyütmek genleştirmek
farming	çiftçilik
feed	Beslemek, gıda vermek yem, yemek	as well  so devrik cümle ,too	de, da
generation		Nor devrik olumsuzda Neither devrik Etheir cümle olumlu	de da
humidity	Rutubet, nem.
hydroponics	ilaçlı su içinde bitki yet iştirme metodu.

72 THE BASIS OF REFRIGERATION

If we are to find a way of making objects cold, we must find a good refrigerant; that is, a liquid that will evaporate readily. Yet, rapid evaporation cannot be the only reason for selection. There are certain other considerations. The liquid must not be too costly, it must not be poisonous, it must not be explosive. What liquid, then, is best of all?

When a liquid evaporates, its molecules escape from a crowded condition Into a space where they are freer to move. If we start with a substance that is normally in the gaseous form and compress it by means of a pump, the molecules exert great pressure in flying to escape from their confinement. If we allow a very small hole through which they might leave, they rush out rapidly. In doing so, they absorb heat energy from their surroundings, just as the molecules of an evaporating liquid do. If you want evidence that this heat absorption really takes place, hold your hand in the escaping air from an automobile tyre. The rapid exit of air molecules into less crowded conditions results in a cooling effect just as great as the cooling that follows the spreading of liquid alcohol over your hand.

Thus, the problem of finding a suitable refrigerant becomes ~'t of selecting the most suitable gas to be compressed. Many have been tried. Ammonia, carbon dioxide, ethyl chloride, and even steam have been and are used.

In an electric refrigerator, seen in many homes, the refrigerant is usually what we call Freon-12 gas. An electric motor drives a pump that compresses the refrigerant into an air-cooled tank. Then, rapid expansion or evaporation takes place in a coil of pipes surrounding the ice-cube trays. Not only does the coil freeze the water in the trays, but it cools the air in the surroundings. The cold air falls, and a convection current is set up, which bathes all the food in the stream of cold air The electric switch which controls the motor is adjusted so that automatically starts the motor when the circulating air gets too warm. It also stops the motor when the air cools to the desired temperature The switch is set to operate at about 40⁰F, and it depends for its~ automatic action upon a strip of metal known as a compound bar. The expansion of such a bar, due to heating, may be used to operate switches and valves.

In a gas refrigerator, there is a reservoir containing ammonia water. When the lower gas flame is burning, the ammonia water rises through the tube to the 'generator. The upper gas flame drives off the ammonia gas, which passes into the ‘condenser'. The cold air around the condenser rapidly brings down the temperature of the gas. Then the cooled gas, now condensed into a liquid, passes into the 'evaporator', which contains hydrogen. In the evaporator, the ammonia expands rapidly, especially since its expansion in hydrogen is greater than it would be in air. This rapid expansion greatly lowers its temperature. It is the cooling of the gas in the evaporator which lowers the temperature of the whole refrigerator and freezes the water in the ice-cube trays.

allow	bırakmak, izin vermek, müsaade etmek	hold	tutmak; bırakmamak, zapt etmek
ammonia water	amonyak suyu	poisonous	zehirli; kötü; igrenç, berbat
compress	sıkmak, basmak, tazyik etmek	readily	Isteyerek kolayca, güçlük çekmeden
condition	hal, durum, vaziyet ; sağlık; şart	refrigerant	serinlik verici, soğutkan
confinement	hapis, mahpusluk; logusalik	refrigeration	soğutma, dondurma.
consideration	saygı, düşünce	reservoir	su haznesi, su deposu,
convection	konveksiyon, ısı yayımı, iletim.	rush	acele etmek; kosmak, segirtmek; acele ettirmek
exert	(çaba, gayret, güç, vb.) sarf etmek, kullanmak	selection	ayırma, ayrılma seçme seçilme
expansion	büyüme, genişleme	set up	kurmak
explosive	patlayıcı	surrounding	çevredeki, civardaki
flame	alevlenmek; parlamak alev; ates	switch	anahtar, anahtarlamak,
gaseous	gazlı, gaz gibi	take place	meydana gelmek, vuku bulmak; geçmek
		tray	tepsi, sini; tabla.
		upper	Üstü, üstteki.
		Yet	Henüz yinede

convection current konveksiyon akimi

73 ANTI-RADIATION PILLS FOR FAMILIES

By Jenny Hope …Newly 1,000 people living near Britain's oldest nuclear power station art to be given anti-nuclear pills. It is the first time the tablets - potassium iodate - have been issued for emergency use to the public. The move has been ordered by Gloucestershire County Council as