矿大博士化工复试翻译真题

(1) The moisture content of Latrobe Valley brown coals,of 59-66%(wet basis ,wb),is a major factor affecting the thermal efficiency of power generation.Removal of the moisture from brown coal as a liquid prior to combustion has the potential to conserve significant amounts of energy compared with the current approach,where all water is removed by evaporation.A number of non-evaporative brown coal dewatering processes have been investigated. Currently,the Cooperative Research Centre (CRC) for Clean Power from Lignite is developing a process called Mechanical Thermal Expression (MTE),which has been chosen because of the lower processing temperature and lower energy demand compared to most other approaches.

(2)The process is presently being developed for retrofit to existing power plants, but could also be integrated into new plants based on advanced power generation technologies.The MTE process,originally proposed and developed in Germany,involves the application of heat (100-300℃) and pressure (6-24MPa) to the coal via electrical/steam heating and a mechanical press.It is envisaged that low grate excess heat from the power station will be utilised in this process.Typically,MTE treated Latrobe Valley coal has a moisture content of 25-35%(wb).Development f the MTE process in Australia started with laboratory scale studies,based on dewatering 100 g of raw coal.A pilot scale evaluation,at 1 tonne of raw coal/hour,has recently been

completed and the development of a larger 15 tonne of raw coal/hr demonstration plant is currently underway.As the scale of the MTE process increases,the volume of product water produced will increase proportionately.

(3) Among the greatest developments of chemical physics in the early twentieth century were the discoveries of ways to peer into molecules and deduce the arrangement in space of their constituent atoms.Most information of this type today comes from three sources: X-ray crystallography,electron diffraction,and microwave spectroscopy.The arrangement of atoms in the crystalline solid state can be determined by X-ray crystallography.This technique,discovered in 1915 and revolutionized in recent years by the availability of high-speed computers,uses the fact that X-ray are diffracted from the atoms of a crystal in precise patterns that can be translated into a molecular structure.In 1930 another technique,electron diffraction ,was developed from the observation that electrons are scattered by the atoms in molecules of gaseous substance.The diffraction patterns resulting from this scattering can also be used to deduce the arrangements of atoms in molecules.Following the development of radar in World War II came microwave spectroscopy,in which the absorption of microwave radiation by gaseous molecules provides structural information.

(4)In addition to excimer sensing,which propelled pyrene to the status