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智科眼: 双语看懂新世界
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Scientists(科学家) from() Lawrence(劳伦斯) Livermore(利弗莫尔) National(国家) Laboratory(实验室) (LLNL)((LLNL)) used(利用) giant(巨型) lasers(激光) to(to) flash()-()freeze(冷冻) water() into() its() exotic() superionic(超离子) phase() and() record(记录) X-(X-)ray(射线衍射) diffraction patterns(衍射图) to(to) identify(识别) its() atomic structure(原子结构) for(for) the very() first(首次) time(时间)()all(所有) in(in) just(just) a(a) few() billionths(十亿分之一) of(of) a(a) second().(.) The findings(研究结果) are(are) reported(报道) today(今天) in(in) Nature(自然).(.)
In(In) 1988,(1988,) scientists(科学家们) first(首次) predicted(预测) that(that) water() would() transition(转变) to(to) an(an) exotic() state(状态) of(of) matter(物质) characterized(特征) by(by) the coexistence(共存) of(of) a(a) solid(固体) lattice(格子) of(of) oxygen(氧气) and() liquid(液体)-()like() hydrogen()()superionic(超离子) ice()()when(when) subjected(经受) to(to) the extreme pressures(特高压力) and() temperatures(温度) that(that) exist(存在) in(in) the interior(内部) of(of) water()-()rich(丰富) giant planets(巨行星) like(喜欢) Uranus(天王星) and() Neptune(海王星).(.) These(These) predictions(预测) remained() in(in) place(发生) until() 2018,(2018,) when(when) a(a) team(团队) led(领导) by() scientists(科学家) from(from) LLNL(LLNL) presented(提出了) the first(第一个) experimental evidence(实验证据) for(for) this(这种) strange(奇怪) state(状态) of(of) water().(.)
Now(现在),(,) the LLNL(LLNL) scientists(科学家) describe(描述了) new(新的) results(结果).(.) Using(利用) laser(激光)-()driven(驱动) shockwaves(冲击波) and() in-(in-)situ(原位) X-(X-)ray(射线衍射) diffraction(衍射),(,) they(他们) observe(观察) the nucleation(成核) of(of) a(a) crystalline lattice(晶格) of(of) oxygen() in(in) a(a) few() billionths(十亿分之一) of(of) a(a) second(),(,) revealing(揭示了) for the first time(首次) the microscopic structure(显微结构) of(of) superionic(超离子) ice().(.)
The data(数据) also() provides(提供了) further(进一步) insight(了解) into(into) the interior structure(内部组织) of(of) ice() giant planets(巨行星).(.)
"We("We) wanted to(想要) determine(确定) the atomic structure(原子结构) of(of) superionic(超离子) water(),"(,") said() LLNL(LLNL) physicist(物理学家) Federica(Federica) Coppari(Coppari),(,) co-(共同)lead() author(作者) of(of) the paper(论文).(.) "(")But() given(给定) the extreme conditions(极端条件) at(at) which(which) this(这种) elusive(难以捉摸) state(状态) of(of) matter(物质) is(is) predicted(预测) to(to) be(be) stable(稳定),(,) compressing(压缩) water() to(to) such(这样) pressures(压力) and() temperatures(温度) and(and) simultaneously(同时) taking(考虑) snapshots(快照) of(of) the atomic structure(原子结构) was(was) an(an) extremely(极其) difficult(困难) task(任务),(,) which(which) required(需要) an(an) innovative(创新) experimental design(实验设计).(.) "(")
The researchers(研究人员) performed(进行) a(a) series(一系列) of(of) experiments(实验) at() the Omega(ω) Laser(激光) Facility(设施) at(at) the University(大学) of(of) Rochester()'s('s) Laboratory() for(for) Laser(激光) Energetics(能量学) (LLE).((LLE).) They(他们) used(使用) six() giant(巨大) laser beams(激光束) to(to) generate(产生) a(a) sequence() of(of) shockwaves(冲击波) of(of) progressively() increasing(增加) intensity(强度) to(to) compress(压缩) a(a) thin layer(薄层) of(of) initially(最初) liquid(液态) water() to(to) extreme pressures(特高压力) (100-400((100-400) gigapascals(千兆帕) (GPa),((GPa),) or() 1-4(1-4) million(百万) times() Earth(地球)'s('s) atmospheric pressure(气压))()) and() temperatures(温度) (3,000-5,000((3,000-5,000) degrees Fahrenheit(华氏度数)).().)
"We("We) designed(设计) the experiments(实验) to(to) compress(压缩) the water() so(so) that(that) it() would(would) freeze(冻结) into(into) solid(固体) ice(),(,) but() it(it) was(was) not() certain(确定) that(that) the ice crystals(冰晶) would() actually() form(形成) and() grow(生长) in(in) the few() billionths(十亿分之一) of(of) a(a) second() that(that) we(我们) can() hold(保持) the pressure(压力)-()temperature conditions(温度情况),"(,") said() LLNL(LLNL) physicist(物理学家) and(and) co-(联合)lead(主要) author(作者) Marius(Marius) Millot(Millot).(.)
To(To) document(记录) the crystallization(结晶) and() identify(确定) the atomic structure(原子结构),(,) the team(团队) blasted() a(a) tiny() iron() foil() with(with) 16(16) additional(额外) laser(激光) pulses(脉冲) to(to) create(创建) a(a) hot plasma(热等离子体),(,) which(which) generated(产生) a(a) flash(闪光) of(of) X-(X-)rays(射线) precisely(精确) timed(定时) to(to) illuminate() the compressed(压缩) water sample(水样) once(一旦) brought(产生) into() the predicted(预测) stability(稳定性) domain() of(of) superionic(超离子) ice().(.)
"(")The X-(X-)ray(射线衍射) diffraction patterns(衍射图) we(我们) measured(测量) are(are) an(an) unambiguous() signature(标志) for(for) dense(致密) ice crystals(冰晶) forming(形成) during(during) the ultrafast(超快) shockwave(冲击波) compression(压缩) demonstrating(证明) that(that) nucleation(成核) of(of) solid(固体) ice() from(来自) liquid(液态) water() is(is) fast() enough(足以) to(to) be(be) observed(观察) in(in) the nanosecond(纳秒) timescale(时间尺度) of(of) the experiment(实验),"(,") Coppari(Coppari) said().(.)
"In("In) the previous() work(工作) we(我们) could(could) only(只能) measure(测量) macroscopic properties(宏观性质) such as(例如) internal energy(内能) and() temperature(温度),"(,") Millot(Millot) added(补充道).(.) "(")Therefore(因此),(,) we(我们) designed(设计了) a(a) new(新的) and(and) different(不同) experiment(实验) to(to) document(记录) the atomic structure(原子结构).(.) Finding(寻找) direct(直接) evidence(证据) for(for) the existence(存在) of(of) crystalline lattice(晶格) of(of) oxygen(氧气) brings(带来了) the last(最后) missing(缺失) piece() to(to) the puzzle(难题) regarding(关于) the existence(存在) of(of) superionic() water ice(冰糕).(.) This() gives() additional strength(附加强度) to(to) the evidence(证据) for(for) the existence(存在) of(of) superionic(超离子) ice() we(我们) collected(收集) last year(去年).(.) "(")
Analyzing(分析) how(how) the X-(X-)ray(射线衍射) diffraction patterns(衍射图) varied(变化) for(for) the different(不同) experiments(实验) probing(探测) increased(增加) pressure(压力) and() temperature conditions(温度情况),(,) the team(团队) identified(确定) a(a) phase transition(相变) to(to) a(a) previously(先前) unknown(未知) face-centered(面心)-()cubic(立方) (f.c.c.)((f.c.c.)) atomic structure(原子结构) for(for) dense(密集) water ice(冰糕).(.)
"(")Water() is(is) known(已知) to(to) have(具有) many(许多) different(不同) crystalline structures(晶体结构) known as(被称为) ice() Ih,(Ih,) II,(II,) III,(III,) up(up) to(to) XVII,"(XVII,") Coppari(Coppari) said().(.) "So,("So,) we(我们) propose(提出了) to(to) call(称为) the new(新的) f.c.c.(f.c.c.) solid(实体) form(形式) 'ice('ice) XVIII.'(XVIII.') Computer simulations(计算机模拟) have(已经) proposed(建议) a number of(许多) different(不同) possible(可能) crystalline structures(晶体结构) for(for) superionic(超离子) ice().(.) Our(我们) study(研究) provides(提供了) a(a) critical(关键) test(测试) to(to) numerical methods(数值方法).(.) "(")
The team(团队)'s('s) data(数据) has(has) profound(深远) implications(影响) for(for) the interior structure(内部组织) of(of) ice() giant planets(巨行星).(.) Since(由于) superionic(超离子) ice() is(is) ultimately(最终) a(a) solid(固体),(,) the idea(概念) of(of) these(these) planets(行星) having(具有) a(a) uniform(均匀) rapidly(快速) convecting(对流) fluid layer(流体层) no longer(已不) holds(成立).(.)
"(")Because(因为) water ice(冰糕) at(at) Uranus(天王星) and() Neptune(海王星)'s('s) interior(内部) conditions(条件) has(has) a(a) crystalline lattice(晶格),(,) we(我们) argue() that(that) superionic(超离子) ice() should() not() flow(流动) like(一样) a(a) liquid(液体) such as(例如) the fluid(流体) iron() outer() core() of(of) the Earth(地球).(.) Rather(相反),(,) it's(it's) probably(可能) better(更好地) to(to) picture(描绘) that(that) superionic() ice() would() flow(流动) similarly() to(to) the Earth(地球)'s('s) mantle(地幔),(,) which(which) is(is) made() of(of) solid rock(坚石),(,) yet() flows(流动) and() supports(支持) large-scale(大型) convective(对流) motions(运动) on(on) the very() long() geological(地质) timescales(时间尺度),"(,") Millot(Millot) said().(.) "(")This() can(可以) dramatically(极大地) affect(影响) our(我们) understanding(理解) of(of) the internal structure(内部组织) and() the evolution(演化) of(of) the icy(冰冷) giant planets(巨行星),(,) as well as(以及) all(all) their(他们) numerous(众多) extrasolar(太阳系外) cousins().(.) "(")

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