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何谓高聚物的玻璃化转变温度简述其影响因素。

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何谓准晶如何描绘准晶态结构

从内部微观结构角度简述纳米材料的特点。

简述利息的实质。

Obtaining Drinking Water from Air Humidity Not a plant to be seen, the desert ground is too 51 . But the air contains water, and research scientists have found a 52 of obtaining drinking water from air humidity. The system is based 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 desert1 in Israel2, for example, annual average relative air humidity is 64 percent -- in every cubic meter of air there are 11,5 milliliters of water. German research scientists have found a way of converting this air humidity autonomously into drinkable water. "The process we have developed is based exclusively on renewable energy sources such as thermal 53 collectors and photovoltaic cells, which makes this method completely energy-autonomous. It will therefore function in regions 54 there is no electrical infrastructure," says Siegfried Egner, head of the research team. The principle of the 55 is as follows3: hygroscopic brine ~ saline solution which absorbs moisture -- runs down a tower-shaped unit and absorbs water from the air. It is then sucked into a tank a few meters 56 the ground in which a vacuum prevails4. Energy from solar collectors heats up the brine, which is diluted by the water it has 57 . Because of the vacuum, the boiling point of the liquid is 58 than it would be under normal atmospheric pressure. This effect is known from the mountains: as the atmospheric pressure 59 is lower than in the valley, water boils at temperatures 60 below 100oC. 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 continuously produces the vacuum and so a vacuum pump is not needed. The reconcentrated5 brine runs down the tower surface 61 to absorb moisture from the air. "The concept is suitable for various water 62 . Single-person units and plants 63 water to entire hotels are conceivable," says Egner. Prototypes have been built for both system components— air moisture absorption and vacuum evaporation —and the research scientists have already 64 their interplay on a laboratory scale. In a further step the researchers intend to develop a demonstration 65 .