没人注意到这条新闻吗？

尼古拉斯-方 {:3_90:}

MD又有东西对付咱了...

好东西，中国制造开始昂视

听起来像是个故意造得乱糟糟的蜂巢，好吧，在被压扁前它能承受几个大气压？

我估计拿这个当核潜艇材料........那钱能造艘小航妈了吧.........不过作成特种部队用的小黑鱼大概可以吧........

MD有的我们坚决山寨之

全世界的精英都去了米国。TNND，怎么可能不牛逼、

果然是超材料…………

那鸟人像是亚裔，具体说像中国人。国家的悲哀。

二维声学隐形外罩怎么给三维物体声学隐身呢？

想不明白。。。

游遍世界 发表于 2011-1-7 20:56
中国容不下精英。看看历史上的知识分子悲惨下场。

madwolf 发表于 2011-1-7 21:41

同一你的前半句话

JY=知识分子？？？

高论

切
我大NJU连声半导体理论模型和首个实体都弄出来了
这姓方的家伙还在整这个破玩意，prl怎么让发这种没创意的烂成果

Nature Materials | Letter
An acoustic rectifier
B. Liang,X. S. Guo,J. Tu,D. Zhang& J. C. Cheng
Affiliations Contributions Corresponding authors Journal name:
Nature Materials
Volume:
9,
Pages:
989–992
Year published:
(2010)
DOI:
doi:10.1038/nmat2881
Received 17 June 2010 Accepted 15 September 2010 Published online 24 October 2010
Read the full articleInstant access to this article:
US$18
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The detection of acoustic signals is of relevance for a range of practical applications, for example in medical diagnostics. However, whereas rectification of electric current and other energy forms such as thermal flux has been demonstrated1, 2, 3, 4, 5, 6, acoustic rectification has not yet been achieved. Here, on the basis of the earlier theoretical proposal of an ‘acoustic diode’7, we present the first experimental demonstration of a rectified energy flux of acoustic waves. A one-dimensional acoustic rectifier is fabricated by coupling a superlattice with a layer of ultrasound contrast agent microbubble suspension. A significant rectifying effect is observed within two frequency bands at locations that agree well with theoretical predictions. Following optimization of the concentration of the microbubble suspension, rectifying ratios can be as high as ∼104. This realization of an acoustic rectifier should have substantial practical significance, for example in the focusing of ultrasound in medical applications.

View full text

Subject terms:Composites Mechanical properties
Figures at a glance
leftFigure 1: Schematic of the experimental system and the cross-section configuration of the AD structure.  
The AD device was formed by coupling a superlattice with a NLM. The left and right parts of the sample refer to the superlattice and the NLM, respectively. The superlattice is fabricated by alternately laminating six water layers (denoted as I) and six glass layers (denoted as II) in a periodic manner. The grey regions represent the aluminium tubes containing the superlattice and the NLM. Two broadband transducers are used for measuring the acoustic transmission, one as a transmitter and the other as a receiver. The measurements are conducted within a water tank.
Figure 2: Measured frequency dependence of acoustic transmission for the superlattice.  
The green regions denote two theoretically predicted ERBs (ERB 1 or 2), in which the frequencies of the incident waves fall in the stop bands of the superlattice and their corresponding doubled frequencies sit in the pass bands (gold regions).
Figure 3: Comparison of the measured frequency dependence of acoustic transmissions along two opposite directions for the AD models formed with three different NLM samples.  
a–c, Results for NLM samples produced using SonoVue microbubble suspensions with volume concentrations of ∼0.025% (a), 0.05% (b) or 0.1% (c). The solid and the dashed lines refer to transmissions along the positive and the negative directions, respectively.
Figure 4: Comparison of the rectifying ratios for the AD models formed with three different NLM samples.  
Results for NLM samples produced using SonoVue microbubble suspensions with volume concentrations of ∼0.025% (blue line), 0.05% (red line) or 0.1% (black line), respectively, corresponding to the three cases in Fig. 3.
Figure 5: Comparison of the pressure dependence of the transmitted acoustic energy flux for the AD models formed with three different NLM samples.  
Results for NLM samples produced using SonoVue microbubble suspensions with volume concentrations of ∼0.025% (blue line), 0.05% (red line) or 0.1% (black line), respectively, corresponding to the three cases in Figs 3 and 4.

These authors contributed equally to this work
B. Liang, X. S. Guo & J. Tu
Affiliations
Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics, Department of Physics, Nanjing University, Nanjing 210093, China
B. Liang, X. S. Guo, J. Tu, D. Zhang & J. C. Cheng
State Key Laboratory of Acoustics, Chinese Academy of Sciences, Beijing 100190, China
B. Liang & J. C. Cheng
Contributions
B.L., X.S.G. and J.T. carried out the experiments and interpreted the data. J.C.C. and D.Z. conceived and supervised the study. All of the authors wrote the paper.

Competing financial interests
The authors declare no competing financial interests.

Corresponding authors
Correspondence to:
D. Zhang or J. C. Cheng

没法发链接，山寨一个
三个w.nature.com/nmat/journal/v9/n12/full/nmat2881.html

切
我大NJU连声半导体理论模型和首个实体都弄出来了
这姓方的家伙还在整这个破玩意，prl怎么让发这种没创意的烂成果

Nature Materials | Letter
An acoustic rectifier
B. Liang,X. S. Guo,J. Tu,D. Zhang& J. C. Cheng
Affiliations Contributions Corresponding authors Journal name:
Nature Materials
Volume:
9,
Pages:
989–992
Year published:
(2010)
DOI:
doi:10.1038/nmat2881
Received 17 June 2010 Accepted 15 September 2010 Published online 24 October 2010
Read the full articleInstant access to this article:
US$18
Buy now Subscribe to Nature Materials for full access: Subscribe
Login for existing subscribers
Additional access options:
Use a document delivery service Login via Athens Purchase a site license Institutional access
British Library Document Supply Centre
Infotrieve
Thompson ISI Document Delivery
You can also request this document from your local library through inter-library loan services.
Article toolsFull text

Print

Email

Download PDF

Download citation

Order reprints

Rights and permissions


Share/bookmark
Connotea
Cite U Like
Facebook
Twitter
Delicious
Digg
The detection of acoustic signals is of relevance for a range of practical applications, for example in medical diagnostics. However, whereas rectification of electric current and other energy forms such as thermal flux has been demonstrated1, 2, 3, 4, 5, 6, acoustic rectification has not yet been achieved. Here, on the basis of the earlier theoretical proposal of an ‘acoustic diode’7, we present the first experimental demonstration of a rectified energy flux of acoustic waves. A one-dimensional acoustic rectifier is fabricated by coupling a superlattice with a layer of ultrasound contrast agent microbubble suspension. A significant rectifying effect is observed within two frequency bands at locations that agree well with theoretical predictions. Following optimization of the concentration of the microbubble suspension, rectifying ratios can be as high as ∼104. This realization of an acoustic rectifier should have substantial practical significance, for example in the focusing of ultrasound in medical applications.

View full text

Subject terms:Composites Mechanical properties
Figures at a glance
leftFigure 1: Schematic of the experimental system and the cross-section configuration of the AD structure.  
The AD device was formed by coupling a superlattice with a NLM. The left and right parts of the sample refer to the superlattice and the NLM, respectively. The superlattice is fabricated by alternately laminating six water layers (denoted as I) and six glass layers (denoted as II) in a periodic manner. The grey regions represent the aluminium tubes containing the superlattice and the NLM. Two broadband transducers are used for measuring the acoustic transmission, one as a transmitter and the other as a receiver. The measurements are conducted within a water tank.
Figure 2: Measured frequency dependence of acoustic transmission for the superlattice.  
The green regions denote two theoretically predicted ERBs (ERB 1 or 2), in which the frequencies of the incident waves fall in the stop bands of the superlattice and their corresponding doubled frequencies sit in the pass bands (gold regions).
Figure 3: Comparison of the measured frequency dependence of acoustic transmissions along two opposite directions for the AD models formed with three different NLM samples.  
a–c, Results for NLM samples produced using SonoVue microbubble suspensions with volume concentrations of ∼0.025% (a), 0.05% (b) or 0.1% (c). The solid and the dashed lines refer to transmissions along the positive and the negative directions, respectively.
Figure 4: Comparison of the rectifying ratios for the AD models formed with three different NLM samples.  
Results for NLM samples produced using SonoVue microbubble suspensions with volume concentrations of ∼0.025% (blue line), 0.05% (red line) or 0.1% (black line), respectively, corresponding to the three cases in Fig. 3.
Figure 5: Comparison of the pressure dependence of the transmitted acoustic energy flux for the AD models formed with three different NLM samples.  
Results for NLM samples produced using SonoVue microbubble suspensions with volume concentrations of ∼0.025% (blue line), 0.05% (red line) or 0.1% (black line), respectively, corresponding to the three cases in Figs 3 and 4.

These authors contributed equally to this work
B. Liang, X. S. Guo & J. Tu
Affiliations
Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics, Department of Physics, Nanjing University, Nanjing 210093, China
B. Liang, X. S. Guo, J. Tu, D. Zhang & J. C. Cheng
State Key Laboratory of Acoustics, Chinese Academy of Sciences, Beijing 100190, China
B. Liang & J. C. Cheng
Contributions
B.L., X.S.G. and J.T. carried out the experiments and interpreted the data. J.C.C. and D.Z. conceived and supervised the study. All of the authors wrote the paper.

Competing financial interests
The authors declare no competing financial interests.

Corresponding authors
Correspondence to:
D. Zhang or J. C. Cheng

没法发链接，山寨一个
三个w.nature.com/nmat/journal/v9/n12/full/nmat2881.html

40千赫到80千赫，这个也只能在空气中用用了。
在水中的话，这个指标可以说是没有太大的现实意义的。

这个人以前是南京大学的，他们做的这个方向国内也有人做，不比他们差，另外，出不出国是个人选择，这人也就是个假洋鬼子，至于楼上有人扯什么知识分子压不压迫的话，纯属没脑子

这个人以前是南京大学的，他们做的这个方向国内也有人做，不比他们差，另外，出不出国是个人选择，这人也就是个假洋鬼子，至于楼上有人扯什么知识分子压不压迫的话，纯属没脑子

回复 15# woshijianmei


    nju南京大学？咱们的技术比他好？

注意到了，出不出国纯属个人选择不错，关键看在哪里更适合个人发展。
不过出去了最好别去搞那些可能会危害自己国家利益的东西，主要是太丧德。

我们的技术既然不差为什么不宣传宣传呢

没看懂

没看懂

MD有的我们坚决山寨之

woshijianmei 发表于 2011-1-7 22:57

居然看到程老师组的校友，汗，顶一个……

楼歪了！
因为是军坛，所以大家都会往它的军事用途上思考，这很正常。但是不要对不了解的人妄下评论。
总不能说因为支撑了原子弹的理论就说E=MC^2是邪恶的。何况爱因斯坦还是德裔呢。

比如，尽管超声波和其他声学成像技术在医学领域非常普遍，但人体内的许多东西会产生干扰，从而破坏了图像的效果。一种由超材料制成的绷带或防护物可能会隐藏一些无关区域，从而扫描仪可以集中对感兴趣区域进行检查。

国外条件的确比国内好，这和是不是受压迫没关系，我们公司就有许多高级技术人员经常受到国外研究机构的邀请，恩，是不是包括我自己呢，恐怕没有，俺只是烧锅炉的，哇卡卡...所以呢，出不出国，完全是个人原因，人总是向往好的生活嘛，很正常。

声学隐形外罩的一大优点就是可以覆盖很宽范围的波长，作用范围从40千赫到80千赫的超声波。当然，改进后的作用范围理论上可覆盖数十兆赫的波长。
也有局限呢

人均GDP上搞到了和MD一个水平了，生活水平还是会有差距。自然条件摆在那里呢。。。

有朝一日TG真的制霸了，估计只会更加疯狂得向外输出人口。只不过到时候在外的华人不再是香蕉了，反而成为了TG的重要砝码～

又是个华人，悲催

可以缺钱但不能缺德。
自古以来中国的知识分子，应有的风骨

松江雪 发表于 2011-1-8 09:10

实在想不透
40KHZ超声波在水中能干嘛, 洗眼镜??

madwolf 发表于 2011-1-7 21:41


    是中国人民容不下这些2B精英。

中美军事资助研究项目获得突破

《科学》一月十六日刊

项目资助单位：美国空军科学研究处，中国国家科学基金会。
研究单位：美国杜克大学，美国北卡大学，中国南京东南大学。

项目：电磁覆盖层
功能：电磁覆盖层材料能够导引电磁波绕过物体而在另一端汇合，如同通过空气。

军事价值：通讯

电磁覆盖层的通俗解释：杜克大学的高级研究人员史密斯解释说，电磁覆盖层现象就如同人们所见过的“海市蜃楼”现象。在高速公路开车经常可以看到前面似乎有一层水在路上漂浮，但这正是对天空的真实折射。当这种“海市蜃楼”现象发生时，“海市蜃楼”就是公路的覆盖层。我们的工作是人工制造这样一个覆盖层。

突破：目前研究人员已经可以人工“操控”微波，几个月后“电磁覆盖层”材料将问世。

史密斯表示，当材料问世后，没有任何东西可以干扰电波的传送。目前的“电磁覆盖层”材料是九个月的艰辛努力的结果。

当被问到波长的时候，史密斯回答：“无限”。

图：电磁覆盖层在平面鼓起一块。通常当微波遇到鼓起的物体后不规则向各个方向折射。但电磁覆盖层可以使微波通过。
  下载 (17.73 KB)

2009-1-22 21:12

左上图为微波射线撞击平面的时候反射的状态，但当撞击到平面突出部位的时候射线分散开来（上中图），使用“电磁覆盖层”后微波顺利通过突出的部分，如同平面反射（右上图）。下面三图显示另外的波长。

  下载 (22.72 KB)

2009-1-22 21:12


《科学》杂志的文章已经在国外网站上开了锅了。许多人对中美进行如此高技术的合作不理解。哈哈。

赶紧山寨啊

笑脸男人 发表于 2011-1-8 19:09


    XE轴心呀。。。

身为南大学生，感到汗颜额，还是好好学习，为国效力吧

南大学生表示这个不用山寨，程老师做的比他好太多了

我又不是党员，党卫军死活跟我有啥关系