考研英语阅读理解精读100篇UNIT20
<p> <span word="TEXT">TEXT</span> <span word="ONE">ONE</span></p><p> <span word="Most">Most</span> <span word="cells">cells</span> <span word="are">are</span> <span word="transparent">transparent</span> <span word="in">in</span> <span word="other">other</span> <span word="words">words</span>, <span word="they">they</span> <span word="are">are</span> <span word="not">not</span> <span word="very">very</span> <span word="good">good</span> <span word="at">at</span> <span word="reflecting">reflecting</span> <span word="or">or</span> <span word="absorbing">absorbing</span> <span word="light">light</span>. <span word="To">To</span> <span word="look">look</span> <span word="at">at</span> <span word="them">them</span> <span word="under">under</span> <span word="a">a</span> <span word="microscope">microscope</span> <span word="thus">thus</span> <span word="requires">requires</span> <span word="trickery">trickery</span>. <span word="Many">Many</span> <span word="of">of</span> <span word="these">these</span> <span word="tricks">tricks</span> <span word="kill">kill</span> <span word="the">the</span> <span word="cells">cells</span>, <span word="and">and</span> <span word="even">even</span> <span word="those">those</span> <span word="that">that</span> <span word="keep">keep</span> <span word="them">them</span> <span word="alive">alive</span> <span word="look">look</span> <span word="only">only</span> <span word="at">at</span> <span word="slices">slices</span> <span word="through">through</span> <span word="each">each</span> <span word="cell">cell</span>, <span word="rather">rather</span> <span word="than">than</span> <span word="seeing">seeing</span> <span word="the">the</span> <span word="whole">whole</span> <span word="thing">thing</span> <span word="in">in</span> <span word="three">three</span> <span word="dimensions">dimensions</span>.</p><p> <span word="Michael">Michael</span> <span word="Feld">Feld</span>, <span word="of">of</span> <span word="the">the</span> <span word="Massachusetts">Massachusetts</span> <span word="Institute">Institute</span> <span word="of">of</span> <span word="Technology">Technology</span>, <span word="and">and</span> <span word="his">his</span> <span word="colleagues">colleagues</span>, <span word="think">think</span> <span word="they">they</span> <span word="can">can</span> <span word="change">change</span> <span word="that">that</span>. <span word="They">They</span> <span word="have">have</span> <span word="invented">invented</span> <span word="a">a</span> <span word="way">way</span> <span word="to">to</span> <span word="look">look</span> <span word="at">at</span> <span word="cells">cells</span> <span word="that">that</span> <span word="are">are</span> <span word="still">still</span> <span word="alive">alive</span>. <span word="Moreover">Moreover</span>, <span word="they">they</span> <span word="can">can</span> <span word="do">do</span> <span word="so">so</span> <span word="in">in</span> <span word="three">three</span> <span word="dimensions">dimensions</span>. <span word="Their">Their</span> <span word="method">method</span> <span word="is">is</span> <span word="called">called</span> <span word="tomographic">tomographic</span> <span word="phase">phase</span> <span word="microscopy">microscopy</span>, <span word="and">and</span> <span word="it">it</span> <span word="is">is</span> <span word="reported">reported</span> <span word="in">in</span> <span word="this">this</span> <span word="weeks">weeks</span> <span word="Nature">Nature</span> <span word="Methods">Methods</span>. <span word="Instead">Instead</span> <span word="of">of</span> <span word="relying">relying</span> <span word="on">on</span> <span word="absorbed">absorbed</span> <span word="or">or</span> <span word="reflected">reflected</span> <span word="light">light</span>, <span word="Dr">Dr</span> <span word="Felds">Felds</span> <span word="technique">technique</span> <span word="celebrates">celebrates</span> <span word="transparency">transparency</span> <span word="by">by</span> <span word="looking">looking</span> <span word="at">at</span> <span word="light">light</span> <span word="that">that</span> <span word="gets">gets</span> <span word="through">through</span> <span word="unaltered">unaltered</span>. <span word="It">It</span> <span word="does">does</span> <span word="so">so</span> <span word="by">by</span> <span word="measuring">measuring</span> <span word="a">a</span> <span word="property">property</span> <span word="called">called</span> <span word="the">the</span> <span word="refractive">refractive</span> <span word="index">index</span>.</p><p> <span word="This">This</span> <span word="index">index</span> <span word="measures">measures</span> <span word="the">the</span> <span word="speed">speed</span> <span word="of">of</span> <span word="light">light</span> <span word="in">in</span> <span word="a">a</span> <span word="material">material</span>. <span word="The">The</span> <span word="different">different</span> <span word="components">components</span> <span word="of">of</span> <span word="a">a</span> <span word="cell">cell</span>, <span word="though">though</span> <span word="transparent">transparent</span>, <span word="have">have</span> <span word="different">different</span> <span word="refractive">refractive</span> <span word="indices">indices</span>. <span word="Dr">Dr</span> <span word="Feld">Feld</span> <span word="and">and</span> <span word="his">his</span> <span word="team">team</span> <span word="therefore">therefore</span> <span word="set">set</span> <span word="out">out</span> <span word="to">to</span> <span word="map">map</span> <span word="what">what</span> <span word="these">these</span> <span word="differences">differences</span> <span word="are">are</span>, <span word="with">with</span> <span word="a">a</span> <span word="view">view</span> <span word="to">to</span> <span word="using">using</span> <span word="them">them</span> <span word="to">to</span> <span word="distinguish">distinguish</span> <span word="between">between</span> <span word="cellular">cellular</span> <span word="components">components</span>.</p><p> <span word="To">To</span> <span word="measure">measure</span> <span word="the">the</span> <span word="refractive">refractive</span> <span word="indices">indices</span> <span word="of">of</span> <span word="different">different</span> <span word="parts">parts</span> <span word="of">of</span> <span word="a">a</span> <span word="cell">cell</span> <span word="they">they</span> <span word="use">use</span> <span word="a">a</span> <span word="technique">technique</span> <span word="called">called</span> <span word="interferometry">interferometry</span>, <span word="which">which</span> <span word="involves">involves</span> <span word="splitting">splitting</span> <span word="a">a</span> <span word="beam">beam</span> <span word="of">of</span> <span word="light">light</span> <span word="in">in</span> <span word="two">two</span>. <span word="One">One</span> <span word="half">half</span>, <span word="known">known</span> <span word="as">as</span> <span word="the">the</span> <span word="object">object</span> <span word="beam">beam</span>, <span word="passes">passes</span> <span word="through">through</span> <span word="the">the</span> <span word="cell">cell</span>; <span word="the">the</span> <span word="other">other</span> <span word="is">is</span> <span word="directed">directed</span> <span word="along">along</span> <span word="a">a</span> <span word="different">different</span> <span word="path">path</span> <span word="and">and</span> <span word="acts">acts</span> <span word="as">as</span> <span word="a">a</span> <span word="reference">reference</span>. <span word="The">The</span> <span word="length">length</span> <span word="of">of</span> <span word="the">the</span> <span word="reference">reference</span> <span word="path">path</span> <span word="is">is</span> <span word="such">such</span> <span word="that">that</span> <span word="if">if</span> <span word="no">no</span> <span word="sample">sample</span> <span word="is">is</span> <span word="present">present</span>, <span word="the">the</span> <span word="two">two</span> <span word="daughter">daughter</span> <span word="beams">beams</span> <span word="will">will</span> <span word="be">be</span> <span word="as">as</span> <span word="perfectly">perfectly</span> <span word="in">in</span> <span word="phase">phase</span> <span word="when">when</span> <span word="they">they</span> <span word="meet">meet</span> <span word="as">as</span> <span word="they">they</span> <span word="were">were</span> <span word="when">when</span> <span word="they">they</span> <span word="were">were</span> <span word="separated">separated</span>. <span word="The">The</span> <span word="crests">crests</span> <span word="and">and</span> <span word="the">the</span> <span word="troughs">troughs</span> <span word="of">of</span> <span word="their">their</span> <span word="waves">waves</span> <span word="will">will</span> <span word="reinforce">reinforce</span> <span word="each">each</span> <span word="other">other</span>, <span word="and">and</span> <span word="the">the</span> <span word="result">result</span> <span word="will">will</span> <span word="be">be</span> <span word="brightness">brightness</span>. <span word="The">The</span> <span word="more">more</span> <span word="that">that</span> <span word="the">the</span> <span word="light">light</span> <span word="passing">passing</span> <span word="through">through</span> <span word="the">the</span> <span word="sample">sample</span> <span word="is">is</span> <span word="slowed">slowed</span> <span word="down">down</span>, <span word="however">however</span>, <span word="the">the</span> <span word="more">more</span> <span word="the">the</span> <span word="two">two</span> <span word="beams">beams</span> <span word="will">will</span> <span word="be">be</span> <span word="out">out</span> <span word="of">of</span> <span word="phase">phase</span>. <span word="Crest">Crest</span> <span word="will">will</span> <span word="fall">fall</span> <span word="on">on</span> <span word="trough">trough</span>, <span word="and">and</span> <span word="the">the</span> <span word="result">result</span> <span word="will">will</span> <span word="be">be</span> <span word="darkness">darkness</span>. <span word="It">It</span> <span word="is">is</span> <span word="this">this</span> <span word="phase">phase</span> <span word="shift">shift</span> <span word="that">that</span> <span word="gives">gives</span> <span word="Dr">Dr</span> <span word="Felds">Felds</span> <span word="new">new</span> <span word="form">form</span> <span word="of">of</span> <span word="microscopy">microscopy</span> <span word="its">its</span> <span word="name">name</span>.</p>
页:
[1]