CompositeMaterials复合材料中国材料研究学会.docx

1、CompositeMaterials复合材料中国材料研究学会Vol.80,2015*E-Material*Metal Alloy*Organic & Polymer*Composite Materials*Practical Application*Tech News & New TechMCanxixun Information and News ServiceMCanxixun Information and News ServiceContentsTech News & New Tech（技术前沿） 3Researchers manipulate gold-coated nanopart

2、icles with lasers 3研究人员利用激光束操作镀金纳米颗粒 4Study helps understand why a materials behavior changes as it gets smaller 4有助于理解材料在变小时特性发生改变的原因的研究 6Squeezing out new science from materials interfaces 7材料界面新科学 8New “knobs” can dial in control of materials 10新“旋钮”控制材料性能 11Metal Alloy（金属合金） 11Watching alloys ch

3、ange from liquid to solid could lead to better metals 11合金由液态变为固态或产生更好的金属 13Composite Materials（复合材料） 15ThermHex Waben develop One-Step Production Process for Sandwich Materials 15ThermHex Waben开发出“一步式”夹层材料生产工艺 15Artificial skin changes colour to order 16人造材料改变颜色 17US moves to develop composite mark

4、et 17美国将开发复合材料市场 18Practical Application（实际应用） 18New material captures carbon at half the energy cost 18新材料吸收二氧化碳，节能一半 20Researchers identify materials to improve biofuel, petroleum processing 22研究人员发现可提高生物燃料与石化工艺的材料 24New material to produce clean energy 25可生产清洁能源的新材料 26Process identified for impro

5、ving durability of glass 27提高玻璃耐用性的新方法 28Organic & Polymer（有机高分子材料） 29Fibers made by transforming materials 29转变材料制造纤维 30Optical fibers light the way for brain-like computing 31光学纤维为类脑计算奠基 32E-Material（电子材料） 33The future of electronics could lie in material from the past 33过去的材料决定电子设备的未来 33Simulatio

6、ns provide new insight into emerging nanoelectronic device 34模拟为纳米电子设备提供新思路 35Technology could cut costs of night vision, thermal imaging 36新技术可以降低夜视与热成像的成本 37New technology may double radio frequency data capacity 38新技术或使无线电频率数据容量加倍 39Tech News & New Tech（技术前沿）Researchers manipulate gold-coated nan

7、oparticles with lasersTiny glass nanospheres coated on one side with a very fine gold film: Ludwig Maximillian Univ. of Munich (LMU) scientists have shown that particles modified in this way can be moved about with high precision using laser beams, creating an optically controlled micro-elevator.The

8、y owe their name to the two-faced Roman god Janus. Symbol of the turning year, Janus looks back and looks forward at the same time, just like so-called Janus particles, which display two different faces to the world. A research team led by the LMU physicists Prof. Jochen Feldmann and Dr. Alexander U

9、rban, both affiliated with the Nanosystems Initiative Munich (NIM) Cluster of Excellence, has now synthesized a class of Janus particles which, thanks to the distinct properties of their two hemispheres, can be manipulated with unprecedented precision with laser beams.If a laser beam is focused by t

10、he lens of a microscope, it can be used as an optical tweezers to trap a nanoparticle at the focal point of the beam. The effect makes use of the forces exerted by the scattering of the light waves that impinge on the particle. The ability not just to trap particles, but also to control their displa

11、cement by means of laser light would be extremely useful for a wide range of applications, such as the analysis of liquid samples with the aid of microfluidics chips, says Urban. But up to now, optical tweezers for this purpose was hampered by the fact that the position and direction of displacement

12、 of particles could not be controlled with sufficient precision.Asymmetric gilding allows manipulationUrbans team has now overcome this limitation, by using quite a simple trick: The scientists introduced an asymmetry into the system by coating glass nanospheres with a wafer-thin layer of gold on on

13、e face. This layer is only 5 nm thick, about 20 times thinner than gold leaf, says Urban. The gold-coated hemisphere of such a so-called Janus particle heats up when irradiated by the laser beam, while the glass side is unaffected because it is not metallic and does not conduct heat. If such a Janus

14、 particle is placed in water, heating of the gold surface generates a temperature gradient, which causes the particle to move upwards toward the light source.Control of the direction of movementHow far it moves and in which direction can be precisely controlled by modifying the balance of forces exe

15、rted by the laser on the particle: Scattering forces control the orientation of the particle in space and confine it within the beam, while the intensity of the laser can be used to alter the level of heating and hence to regulate the distance traversed by the particle in the third dimension. Thus,

16、by varying the laser power, the researchers can raise or lower the level of the particle within the laser beam, as if it were a passenger in an elevator: Increasing the intensity of the beam causes the particle to rise; reducing the power results in downward motion.This new technique allows one to c

17、ontrol particle motions with unprecedented precision and can be used in many different and interesting settings, says Urban. Indeed, the scientists have already taken a further step by successfully using laser beams to capture a gold nanosphere together with the new Janus particle and then showing t

18、hat they could change the distance between the two particles at will. This demonstrates that our laser-powered elevator provides a versatile tool for use in basic research as well as in many practical applications. It could, for example, serve as the basis of a device for the measurement of extremel

19、y weak forces, in which a molecule is suspended between particles and one could use the laser to measure the force required to pull the particles apart, says Urban.Source: Ludwig Maximillian Univ. of Munich研究人员利用激光束操作镀金纳米颗粒微小的玻璃纳米微球在一侧包覆了非常细的金薄膜。慕尼黑-路德维希-马克西米利安大学（LMU）的科学家研究发现，通过这种方法修改的颗粒可以用采用高精度的激光束

20、进行移动，制造出一个光控制的微电梯。他们以罗马两面神Janus来命名。作为一年更替的象征，Janus能够同时向前后两面看，就像所谓的Janus颗粒一样能向世界展示两个不同的面孔。由隶属于慕尼黑纳米系统研究基地的LMU物理学家Jochen Feldmann教授和Alexander Urban博士领导的一个研究小组现已合成了一类Janus颗粒。由于它们两个不同半球体的不同特性，可以通过激光束以前所未有的精度对这些颗粒进行操作。如果通过显微镜镜片对激光束进行聚焦，它就可以用作光学镊子在光束的焦点处捕获纳米颗粒。这种效果利用的是光波散射在颗粒上所施加的力。Urban说：“它能做的不仅仅是捕获颗粒，而且

21、还能通过激光装置控制其移动，其应用范围将会非常广泛，比如借助微流体芯片来分析液体样本。但是到现在为止，光学镊子在这方面的应用还面临着一定的阻碍，因为目前还不能以足够的精度来控制颗粒移动的位置和方向。”不对称镀金使操作成为可能Urban的团队通过很简单的技巧克服了这种局限性。这些科学家将不对称引入到该系统中，通过极薄的金薄膜在颗粒的一个面上对玻璃纳米微球进行了镀膜操作。Urban说：“这种膜只有5纳米厚，比金箔薄20倍左右。” 这种所谓的Janus颗粒的镀金半球在激光束照射时会变热，而玻璃的那一面不会受到影响，因为它不是金属的且不会导热。如果这种Janus颗粒放入水中，加热金属表面会形成温度梯度

22、，这会导致颗粒朝向光源向上移动。控制移动方向通过改变激光施加在颗粒上的力的平衡可以精确地控制它朝哪个方向移动以及能移动多远。散射的力度控制颗粒在空间中的方位并将其限制在激光束范围之内，而激光的强度可用于改变热的程度并进而调节颗粒在三维空间移动的距离。因此，通过改变激光功率，研究人员可以提高或降低激光束内的颗粒水平，就好像它是电梯的乘客一样。增加激光束的强度会引起颗粒上升，而降低功率则会导致其向下移动。Urban说：“这种新的技术允许人们以前所未有的精度来控制颗粒运动，并且可应用于很多不同的有趣装置中。”事实上，科学家们已经取得了很大的进展，成功利用激光束捕获了与Janus颗粒在一起的金纳米球，

23、并且展示出他们有能力随意改变颗粒之间的距离。Urban说：“这表明我们的激光动力电梯为基础研究和很多实际应用提供了一种通用工具。例如，它可以用作一个装置的基础以通过极弱的作用力来进行测量，其中分子颗粒是悬浮的，我们可以使用激光来测量出把这些颗粒分开所需的力的大小。”来源：慕尼黑-路德维希-马克西米利安大学Study helps understand why a materials behavior changes as it gets smallerTo fully understand how nanomaterials behave, one must also understand th

24、e atomic-scale deformation mechanisms that determine their structure and, therefore, their strength and function.Researchers at the Univ. of Pittsburgh, Drexel Univ. and the Georgia Institute of Technology have engineered a new way to observe and study these mechanisms and, in doing so, have reveale

25、d an interesting phenomenon in a well-known material, tungsten. The group is the first to observe atomic-level deformation twinning in body-centered cubic (BCC) tungsten nanocrystals.The team used high-resolution transmission electron microscope (TEM) and sophisticated computer modeling to make the

26、observation. This work, published in Nature Materials, represents a milestone in the in-situ study of mechanical behaviors of nanomaterials.Deformation twinning is a type of deformation that, in conjunction with dislocation slip, allows materials to permanently deform without breaking. In the proces

27、s of twinning, the crystal reorients, which creates a region in the crystal that is a mirror image of the original crystal. Twinning has been observed in large-scale BCC metals and alloys during deformation. However, whether twinning occurs in BCC nanomaterials or not remained unknown.“To gain a dee

28、p understanding of deformation in BCC nanomaterials, we combined atomic-scale imaging and simulations to show that twinning activities dominated for most loading conditions, due to the lack of other shear deformation mechanisms in nanoscale BCC lattices.” said Scott Mao, a professor in the Swanson S

29、chool of Engineering at the Univ. of Pittsburgh.The team chose tungsten as a typical BCC crystal. The most familiar application of tungsten is their use as filaments for light bulbs.The observation of atomic-scale twinning was made inside a TEM. This kind of study has not been possible in the past,

30、due to difficulties of making BCC samples less than 100 nm in size, as required by TEM imaging. Jiangwei Wang, a graduate student at Univ. of Pittsburgh, and Mao, the lead author of the paper, developed a clever way of making the BCC tungsten nanowires. Under a TEM, Wang welded together two small pi

31、eces of individual nanoscale tungsten crystals to create a wire about 20 nm in diameter. This wire was durable enough to stretch and compress while Wang observed the twinning phenomenon in real time using a high-resolution TEM.To better understand the phenomenon observed by Mao and Wangs team at the

32、 Univ. of Pittsburgh, Christopher Weinberger, an assistant professor in Drexels College of Engineering, developed computer models that show the mechanical behavior of the tungsten nanostructureat the atomic level. His modeling allowed the team to see the physical factors at play during twinning. This information will help researchers theorize why it occurs in nanoscale tungsten and plot a course for examining this behavior in other BCC materials.“Were trying to see if our atomistic-based model