Here the vowels of American English are plotted according to the point of primary obstruction by the tongue in the articulation of the sound. \Low\ refers not only to the position of the tongue but the jaw as well

Scotland Yard This is the headquarters of the London Metropolitan Police. The term is often used, popularly, to refer to one branch, the Criminal Investigation Department (CID). Named after a short street in London, the site of a palace used in the 12th century as a residence of visiting Scottish kings

1. frustrate [ frQs5treit ] 1)阻止(某人)做某 事；破坏(to prevent from achieving an objective) 2) 使沮丧(to cause feelings of discouragement ) The weather frustrated our plans. 天气破坏了我们的计划。 two hour's frustrating delay

1. retract [ ri5trAkt ]缩回,收回(to take back or withdraw) A cat can retract its claws. 猫能缩回爪子。 to retract an offer 收回提议

perceive [ pE5si:v ]察觉;感知(to become aware of through the senses) [助记法] per(全部)+ceive (拿住)－全部拿住－ 发觉 implore [ im5plC: ]恳求, 哀求(to ask for or beg earnestly for) [助记法]im(进入)+plore(悲哀)－进入悲哀－哀 求

“One should beware of mathematicians and all who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and confine man in the bonds of Hell” St Augustine, Bishop of Hippo, circa 400 A.D “To move things is all that Mankind can do…For such the

Crystallization is one of the oldest methods known for recovering pure solids from a solution. The Chinese, for example, were using crystallization to recover common salt from water some 5000 years ago. The perfection and beauty of the crystal which fascinated the early tribes now leads to a product of high purity and attractive appearance

Often in multiple-effect evaporators the concentration of the liquid being evaporated changes drastically from effect to effect, especially in the latter effects. In such cases, this phenomenon can be used to advantage by staging one or more of the latter effects. Staging is the operation of an effect by maintaining

must also consider heating andor cooling requirements as well as to deliver the desired head pressure to overcome hydraulic pressure drop. Operating costs must also consider equipment maintenance, cost of cleaning chemicals and labor costs

The theoretical concepts underlying filtration can be applied towards practical solutions in the field. Comprehension of the basic principles is necessary to select the proper equipment for an application. Theory alone, however, can never be the basis for selection of a filter. Filtration belongs to the physical sciences, and thus conclusions must be based on experimental assay. It is, however, helpful in understanding why a slurry is more suitable for one design of filtration equipment than another