第6部分：完形填空(第51～65题，每题1分，共15分)
下面的短文有15处空白，请根据短文内容为每处空白确定1个最佳选项。
Obtaining Drinking Water from Air Humidity
Not a plant to be seen，the desert ground is too dry．But the air contains water，and research scientists have found a_________(51)of obtaining drinking water from air humidity．The system isbased completely on renewable energy and is therefore autonomous．
Cracks permeate the dried-out desert ground and the landscape bears testimony to the lack of water．But even here，where there are no lakes，rivers or groundwater，considerable quantities of water are stored in the air．In the Negev desert in Israel，for example，annual average relative air hu-midity is 64 percent-in every cubic meter of air there aye 11．5 milliliters of water．
German research scientists have found a way of converting this air humidity autonomously intodrinkable water．"The process we have developed is based exclusively on renewable energy sources_______(52)thermal solar collectors and photovoltaic ceils，_________(53)makes this methodcompletely energy-autonomous．It will_______(54)function in regions where there is no electricalinfrastructure．"says Siegfried Egner，head of the research team．The principle of the_______ (55)is as follows：hygroscopic brine-saline solution which absorbs moistureruns down a tower-shapedunit and absorbs water from the air．It is then sucked_________(56)a tank a few meters off the ground in which a vacuum prevails．Energy from solar collectors_________(57)up the brine，whichis diluted by the water it has________(58).
Because of the vacuum，the boiling point of the liquid is lower thaa it would be under_____ (59)atmospheric pressure．This effect is known from the mountains：as the atmospheric pressure there is lower than in the valley，water boils at temperatures distinctly below 100~C．The evaporated， non-saline water is condensed and runs down through a completely filled tube in a controlled manner．The gravity of this water column_________(60)produces the vacuum and so a vacuum pump is not needed.The reconcentrated brine________(61)down the tower surface again to absorb moisture from the air．
"The concept is suitable for various water_________(62)．Single-person units and plants supplying water to entire hotels are conceivable，"says Egner．Prototypes have been built for______
(63)system components-air moisture absorption and vacuum evaporation-and the research scientistshave Mready________(64)their interplay on a laboratory scale．In a further________(65)the researchers intend to develop a demonstration facility．
51．A．road B．channel C．way D．path
52．A．in spite of B．because of C．as a result of D．such as
53．A．who B．where C．when D．which
54．A．meanwhile B．therefore C．however D．still
55．A．prospect B．process C．progress D．product
56．A．from B．at C．above D．into
57．A．keeps B．brings C．breaks D．heats
58．A．attracted B．affected C．allowed D．absorbed
59．A．normal B．different C．easy D．available
60．A．continuously B．suddenly C．typically D．seriously
61．A．takes B．puts C．flies D．runs
62．A．users B．designers C．owner D．workers
63．A．both B．every C．same D．either
64．A．repaired B．cancelled C．tested D．copied
65．A．instrument B．step C．case D．ground
同时按下Crtl键和A键查看答案
51．c 52．D 53．D 54．D 55．B 56．D 57．D 58．D 59．A 60．A 61．D 62．A 63．A 64．c 65．B
