[材料科学]麦肯息讯报告材料第21期

1、mcanxixun * informationvol.21,2012*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）3novel technique to synthesize nanocryst

2、als that harvest solar energy3合成能够收集太阳能的纳米晶体的新技术3ornl technology moves scientists closer to extracting uranium from seawater4ornl技术使科学家向从海水中提取铀迈进了一步5flexible snake armor could inspire abrasion-resistant materials6灵活的蛇皮肤能够激发出耐磨损材料6designing tiny molecules that glow in water to shed light on biologica

3、l processes7在水中能够发光的微分子的设计阐明了生物程序8patterning defect-free nanocrystal films with nanometer resolution9以毫微米分辨率仿造无缺陷纳米晶体薄膜10new form of carbon can put a dent in a diamond11新形式的碳能够对钻石进行切割12metal alloy（金属合金）12engineers achieve longstanding goal of stable nanocrystalline metals12工程师实现了长期存在的稳定纳米结晶质金属的目标14n

4、ew solar panels made with more common metals could be cheaper and more sustainable15利用更常见的金属制造出的新型太阳能电池板更廉价且持续性更强15gold nanoparticles could treat prostate cancer with fewer side effects than chemotherapy16金纳米颗粒能够在比化学疗法产生更少副作用的条件下治疗前列腺癌17gold nanorods hitch ride on immune cells that target breast tum

5、ors17金纳米棒能够链接把乳腺肿瘤作为目标的免疫细胞18composite materials（复合材料）181-molecule-thick material has big advantages18一个分子厚的材料具有许多优势20super-strong, high-tech material found to be toxic to aquatic animals21超强韧高科技材料被发现对水生动物有毒22cern physicists break record for hottest manmade material22cern物理学家打破了最热人造材料的记录23novel nano

6、-structures to realize hydrogen's energy potential24新型纳米结构能够实现氢的能量潜力25practical application（实际应用）26nanoparticles reboot blood flow in brain26纳米颗粒能够重启大脑中的血流27cleaning up oil spills with graphene sponges28使用石墨烯海绵对石油泄漏进行清理29x-ray imaging technique could unlock small crystal properties30x射线成像技术能够揭示出

7、较小的晶体特性30team investigates potential of bamboo for home construction31小组调查了竹子在房屋建筑中的潜能32portable inflatable tank could reduce eco impact of fracking33便携式可膨胀水箱能够降低水力压裂造成的环境影响34new space-age insulating material for homes, clothing and other everyday uses34具有家庭、服装和其他日常应用的新型太空绝缘材料35organic & polymer

8、（有机高分子材料）36biocompatible cellulose nanostructures could speed wound recovery36生物兼容性纤维素纳米结构能够加速伤口的愈合37biomimetic fibrous scaffolds for tissue engineering37为组织的建造开发出的仿生物纤维支架38behaviors of the tiniest water droplets revealed39极微小的水滴的习性40mineral can reduce pollution from diesel engines by almost half41能

9、够将柴油机产生的污染物降低一半的矿物42e-material（电子材料）43a new route to dissipationless electronics43获得能量不散逸电子设备的一种新方法43self-charging battery both generates and stores energy44既能产生能量又能存储能量的自动充电电池45nanotritium battery is good for twenty years46能够持续工作20年的纳米氚蓄电池46quantum dots for superior solar cells47能够制造出更高效太阳能电池的量子点48

10、printing electronics: high-speed transistors with electrochemical gating49印制电子设备：具有电化学栅极的高速晶体管50ornl researchers probe invisible vacancies in fuel cell materials50ornl研究者探测了燃料电池材料中的隐形空位51scientists produce h2 for fuel cells using an inexpensive catalyst under real-world conditions52科学家使用一种廉价的催化剂在现实条

11、件中为燃料电池生产出了氢气52superconductor 'flaws' could be key to its abilities53超导体中的缺陷对它的性能来说非常重要54tech news & new tech（技术前沿）novel technique to synthesize nanocrystals that harvest solar energyone reason that solar energy has not been widely adopted is because light absorbing materials are not dur

12、able. materials that harvest solar radiation for energy often overheat or degrade over time; this reduces their viability to compete with other renewable energy sources like wind or hydroelectric generators. a new video protocol addresses these issues by presenting a synthesis of two inorganic nanoc

13、rystals, each of which is more durable than their organic counterparts. the article, published in journal of visualized experiments (jove), focuses on the liquid phase synthesis of two nanocrystals that produce hydrogen gas or an electric charge when exposed to light. "the main advantage of thi

14、s technique is that it allows for direct, all inorganic coupling of the light absorber and the catalyst," says the leading author dr. mikhail zamkov of bowling green state university.zamkov's nanocrystals are unique for two reasons: they separate charge in different ways due to their archit

15、ectures, and they are inorganic and durable. the first nanocrystal is rod-shaped, which allows the charge separation needed to produce hydrogen gas, a reaction known as photocatalysis. the second nanocrystal is composed of stacked layers and generates electricity, thus being photovoltaic. because th

16、e nanocrystals are inorganic, they are easier to recharge and less sensitive to heat than their organic counterparts. zamkov's inorganic photocatalytic material allows a rechargeable reaction when exposed to cheap organic solvents, whereas in traditional photocatalytic reactions the catalyst is

17、often irreversibly degraded. the photovoltaic nanocrystals can also withstand higher heat than the traditional photovoltaic cells that do not dissipate heat well."we have established a new method for making photocatalytic and photovoltaic materials. this is important primarily as a new strategy

18、 for making photovoltaic films that are 100% inorganic, thus producing a more stable solar panel. it is a design that you could reach marketability," dr. zamkov says. "it is important to have these steps documented in a video format, as the synthesis of the photocatalytic nanocrystals and

19、the photovoltaic cells are long procedures with detailed steps. it makes our technique more visible and accessible."合成能够收集太阳能的纳米晶体的新技术太阳能还没有被广泛使用的一个原因是因为光线吸收材料的持久性不够强，收集太阳能辐射获得能量的材料通常在经过一段时间之后会变得过热或降解，这也降低了它们在跟例如风能和水电能等的其他可再生能源资源竞争时的生存能力，一个新的录制草案通过两种无机纳米晶体（每一种都要比它们的无机配体持续性更强）的合成解决了这些问题，这篇文章被发表在

20、了journal of visualized experiments (jove)杂志上，它的重点是当暴露到光线中时能够产生氢气或电荷的两种纳米晶体的液相合成，“这项技术的主要优势是它能够使光线吸收器和催化剂进行直接的无机结合，”来自bowling green state university的首席作者mikhail zamkov教授说道。zamkov的纳米晶体很独特的原因有两个：它们由于自身的构筑能够以不同的方式分离电荷；它们是无机的且具有持久性。首个纳米晶体是杆状的，这能够使电荷分离后生产出氢气，这种反应被称作光催化反应；第二种纳米晶体是由堆积层组成的，并且能够发电，因此是光电伏打的。因为

21、纳米晶体是无机的，所以它们更容易进行再充电，并且没有它们的有机配体对热量敏感。zamkov的无机光催化材料在暴露到廉价的有机溶液中时会产生一种再充电的反应，而在传统的光催化反应中催化剂通常会不可避免的产生降解，同时，光生伏打纳米晶体还能够比不能很好散热的传统光生伏打电池承受更高的热量。 “我们建立了制造光催化和光生伏打材料的一种新方法，这作为制造100%无机的光生伏打薄膜的一种新方法来说是非常重要的，从而还能够生产出一种更稳定的太阳能电池板，这是一种能够适应市场销售性需求的设计，”zamkov教授说道，“能够将这些步骤以视频的格式记录下来是很重要的，因为光催化纳米晶体和光生伏打电池的制造过程是

22、具有详细步骤的冗长程序，这也使我们的技术变得更具有可行性。”ornl technology moves scientists closer to extracting uranium from seawaterfueling nuclear reactors with uranium harvested from the ocean could become more feasible because of a material developed by a team led by the department of energy's oak ridge national labora

23、tory. the combination of ornl's high-capacity reusable adsorbents and a florida company's high-surface-area polyethylene fibers creates a material that can rapidly, selectively and economically extract valuable and precious dissolved metals from water. the material, hicap, vastly outperforms

24、 today's best adsorbents, which perform surface retention of solid or gas molecules, atoms or ions. hicap also effectively removes toxic metals from water, according to results verified by researchers at pacific northwest national laboratory."we have shown that our adsorbents can extract fi

25、ve to seven times more uranium at uptake rates seven times faster than the world's best adsorbents," said chris janke, one of the inventors and a member of ornl's materials science and technology division.results were presented august 21 at the fall meeting of the american chemical soci

26、ety in philadelphia.hicap effectively narrows the fiscal gap between what exists today and what is needed to economically extract some of the ocean's estimated 4.5 billion tons of uranium. although dissolved uranium exists in concentrations of just 3.2 parts per billion, the sheer volume means t

27、here would be enough to fuel the world's nuclear reactors for centuries.the goal of extracting uranium from the oceans began with research and development projects in the 1960s, with japan conducting the majority of the work. other countries pursuing this dream include russia, china, germany, gr

28、eat britain, india, south korea, turkey and the united states. many adsorbent materials have been developed and evaluated, but none has emerged as being economically viable.what sets the ornl material apart is that the adsorbents are made from small diameter, round or non-round fibers with high surf

29、ace areas and excellent mechanical properties. by tailoring the diameter and shape of the fibers, researchers can significantly increase surface area and adsorption capacity. this and ornl's patent pending technology to manufacture the adsorbent fibers results in a material able to selectively r

30、ecover metals more quickly and with increased adsorption capacity, thereby dramatically increasing efficiency."our hicap adsorbents are made by subjecting high-surface area polyethylene fibers to ionizing radiation, then reacting these pre-irradiated fibers with chemical compounds that have a h

31、igh affinity for selected metals," janke said.after the processing, scientists can place hicap adsorbents in water containing the targeted material, which is quickly and preferentially trapped. scientists then remove the adsorbents from the water and the metals are readily extracted using a sim

32、ple acid elution method. the adsorbent can then be regenerated and reused after being conditioned with potassium hydroxide.in a direct comparison to the current state-of-the-art adsorbent, hicap provides significantly higher uranium adsorption capacity, faster uptake and higher selectivity, accordin

33、g to test results. specifically, hicap's adsorption capacity is seven times higher (146 vs. 22 grams of uranium per kilogram of adsorbent) in spiked solutions containing 6 parts per million of uranium at 20 degrees celsius. in seawater, hicap's adsorption capacity of 3.94 grams of uranium pe

34、r kilogram of adsorbent was more than five times higher than the world's best at 0.74 grams of uranium per kilogram of adsorbent. the numbers for selectivity showed hicap to be seven times higher."these results clearly demonstrate that higher surface area fibers translate to higher capacity

35、," janke said.ornl researchers conducted field tests of the material at the marine sciences laboratory of pacific northwest national laboratory in sequim, wash., and at the rosenstiel school of marine & atmospheric science and broad key island in collaboration with the university of miami.o

36、ther members of the team include yatsandra oyola, sheng dai, richard mayes, tomonori saito, xiao-guang sun, costas tsouris of ornl, and jim brang and jeff haggard of hills inc. of west melbourne, fla.ornl技术使科学家向从海水中提取铀迈进了一步使用从海洋中收集的铀供给燃料的核反应堆能够变得更具可行性，由于美国能源部橡树岭国家实验室领导的小组所开发出的一种材料。ornl的高容量可重复使用性吸附剂和

37、一家佛罗里达公司的大表面区域聚乙烯纤维的结合制造出了一种能够从水中快速、有选择性和经济节约性的提取出稀有且有价值的溶解性金属的材料，这种材料hicap性能要远远超过目前最好的吸附剂，并且它能够使固体或气体分子、原子和离子产生表面滞留，hicap还能够有效的从水中清除有毒金属，根据西北太平洋国家实验室的研究者所证实的结果。 “我们展示了这种吸附剂能够以比世界上最好的吸附剂快7倍的速率吸收5到7倍多的铀，”chris janke说道，他是发明者之一，同时也是ornl材料科学和技术部门的一名成员。这项研究结果被在美国化学学会于8月21日在费城举行的秋季会议上进行了发布。hicap有效的缩小了目前存在

38、和商业上提取一些海洋中预计45亿吨的铀所需的财政缺口，尽管溶解性的铀只存在于十亿分之3.2的浓度中，然而，正是这个量就足以为世界上的核能反应堆提供几个世纪的燃料。从海洋中提取铀的目标开始于20世纪60年代所进行的研究和发展项目，日本在这些项目中起到了主导作用，其他也在追逐这一目标的国家包括俄罗斯、中国、德国、大不列颠、印度、韩国、土耳其和美国，许多吸附材料被进行了开发和评估，但是他们没有发现任何具有商业可行性的材料。使ornl材料变得突出的是由小直径圆形或非圆形纤维制成的吸附剂，这些纤维具有较大的表面区域和优秀的机械特性，通过对这些纤维的直径和形状进行修改，研究者能够极大的提高表面区域和吸收容

39、量，这和ornl申请专利的制造吸附纤维的技术结合在一起产生了一种材料，这种材料能够更快的有选择性的还原金属，并且具有提升性的吸附容量，因而也极大的提高了效率。 “我们的hicap吸附剂是通过将大表面区域聚乙烯纤维进行电离辐射，然而将这些预辐射的纤维跟与特定金属具有密切联系的化学复合物进行反应而制成的，”janke说道。在这个程序完成以后，科学家会把hicap吸附剂放在含有指定材料（会被快速和优先捕获）的水中，然后，科学家将这些吸附剂从水中清除掉，金属就很容易使用一种简单的酸洗方法被提取出来，最后，这些吸附剂在使用氢氧化钾进行处理之后能够被再生产和再使用。在和目前最先进的吸附剂进行对比的过程中，

40、我们发现hicap能够提供更高的铀吸收容量，并且速度更快和选择性更强，根据测试的结果，特别明显的是，在20摄氏度的条件下，hicap在铀含量达到百万分之六的峰值溶液中吸附容量要提高7倍。在海水中，hicap的每千克吸附剂3.94克铀的吸附容量是世界上最好的每千克吸附剂0.74克铀的吸附容量的超过5倍，选择性的数据显示出hicap的效率值要高7倍。 “这些结果清晰的显示出了更大表面区域的纤维能够表现出更高的容量，”janke说道。ornl研究者和迈阿密大学的同事合作在华盛顿sequim的西北太平洋国家实验室海洋科学实验室和rosenstiel school of marine & atm

41、ospheric science and broad key island对这种材料进行场地测试。这个小组的其他成员包括yatsandra oyola, sheng dai, richard mayes, tomonori saito, xiao-guang sun, costas tsouris of ornl, jim brang和来自fla 西墨尔本希尔斯公司的jeff haggard。flexible snake armor could inspire abrasion-resistant materialssnakes are highly specialized legless a

42、nimals, which evolved around 150 million years ago. although without extremities, their body is exposed to constant friction forces. the phd-student marie-christin klein and professor stanislav gorb of kiel university found out how snake skin is adapted to legless locomotion. the skin is stiff and h

43、ard on the outside and becomes soft and flexible towards the inside, independent of habitat. biology could inspire systems in engineering with minimized abrasion.klein and gorb are publishing their current results in the august 15 of the journal of the royal society interface.sakes inhabit all large

44、 ecosystems apart from the polar regions. they are able to climb trees and burrow underground. the skin, exposed to a good deal of friction, has to last until molding takes place, which is every two to three months. "the skin of snakes therefore has to be optimized against abrasion wear,"

45、assumed marie-christin klein at the beginning of her research.with stanislav gorb she examined the skin of four snake species: sand boa (gongylophis colubrinus), the king snake (lampropeltis getula californiae), the rainbow boa (epicrates cenchria cenchria) and the green tree python (morelia viridis

46、), which inhabit different environments, from the desert to tropical trees. "with the help of these four species we found out that the skin architecture differs depending on habitat. however, all show a gradient in material properties. this means that the skin of all species has a stiff and har

47、d outside and becomes more flexible and soft towards the inside, even though the skin differs in thickness and structure depending on species," explains klein her findings, which confirm her assumption that the skin of snakes is optimized against abrasion wear. the four snake species achieve th

48、is mechanical effect by developing for instance different cell types. one species has a relatively thick skin with round cells, while the other has a relatively thin skin with elongated cells. "this speaks for a functional adaptation to legless locomotion, which has developed for snakes in both

49、 moist and dry habitats," says klein."this research area is extremely new," klein reports. "the general composition of snake skin is known, however, but no one has by now examined the impact of this on the mechanical material properties. a material that has a transition from a st

50、iff outside to a flexible inside can distribute an impacting force over a larger area, therefore decreasing the force on one single point. materials like this are like a flexible amour." possible application areas can be found in the medical engineering sector, in which friction could for insta

51、nce be optimized for artificial implants. furthermore, the propulsion and conveyer technique market could profit from the abrasion minimization findings, since lubrication would have to be implicated less often. the friction system of snake skin is an important model in the bionics research at kiel

52、university (group: zoological institute, professor stanislav n. gorb) for the development of new and the optimization of already existing materials.灵活的蛇皮肤能够激发出耐磨损材料蛇是一种很特别的无腿动物，它是从大约1亿5000万年前进化而来的，尽管没有四肢，他们的身体承受着恒定的摩擦力。博士研究生marie-christin klein和来自基尔大学的stanislav gorb教授发现了蛇的皮肤是如何适应无腿运动的，这种皮肤外部很坚硬，而内部很

53、柔软、很灵活，并且能够不依赖于栖息地，这种生物学机理能够激发出具有最小摩擦的系统的设计。klein和gorb将他们最新的研究结果发布在了royal society interface杂志8月的第15期上。蛇能够栖息在除了极地地区以外的所有大型生态系统中，它们能够爬树，也能够藏身于地下，它们的皮肤承受着大量的摩擦必须支撑到新一轮的塑模成型（每两到三个月发生一次）。“因此，蛇的皮肤必须尽可能达到最佳化来抵抗磨损，”marie-christin klein在她的研究开始时指出。她跟stanislav gorb一起检测了四类蛇的皮肤：沙蟒、蛇王、彩虹蟒和绿树蟒，它们都栖息在不同的环境中，从沙漠到热带雨

54、林，“通过对这四类蛇的观察，我们发现它们皮肤构造的不同主要取决于栖息地，然而，它们在材料特性方面展示出了一种梯度，也就是说这四类蛇的皮肤都有一个坚硬的外表面，而内部很柔软、很灵活，即使基于物种的不同它们皮肤的厚度和结构也有所不同，”klein对于她的发现解释道，这也确认了她关于蛇皮肤会不断优化来抵抗磨损的猜想，这四类蛇通过开发不同的细胞类型而实现了这种机械效应，一种蛇拥有具有圆细胞的相对厚的皮肤，而另外一种拥有具有拉伸细胞的相对薄的皮肤，“这也谈到了对于无腿运动的一个功能适应性，这也是蛇在比较潮湿和比较干燥的栖息地所形成的，”klein说道。 “这个研究领域非常新，”klein补充道，“蛇皮肤

55、的常见构成模式是众所周知的，然而，到目前为止还没有人检查过这种构成对机械材料特性所能产生的影响，一种能够从坚硬外层转化到柔软内层的材料会在许多领域产生重要影响，从而降低单个支撑点所承受的力，这样的材料类似一种柔软的台布。”可能性的应用领域会出现在医疗工程部分，在这个领域里摩擦能够为人造移植物得到优化，进一步来讲，推动机和传送机技术市场也能够从摩擦最小化中获益，由于不需要再频繁的进行摩擦，蛇皮肤的摩擦系统在基尔大学（小组：zoological学院，stanislav n. gorb教授）的仿生学研究中对于现存材料的发展和优化来讲是一种重要的模型。designing tiny molecules

56、that glow in water to shed light on biological processesuniversity of miami scientists have developed a way to switch fluorescent molecules on and off within aqueous environments, by strategically trapping the molecules inside water-soluble particles and controlling them with ultraviolet light. the

57、new system can be used to develop better fluorescent probes for biomedical research.previous studies have used water-soluble particles to bring organic molecules into water. what is novel about this system is the use of a photoswitching mechanism in combination with these particles.the findings publ

58、ished online by chemistry-a european journal, describe the creation of a fluorescent photoswitchable system that is more efficient than current technologies, says francisco raymo, professor of chemistry at the um college of arts and sciences and principal investigator of this study."finding a w

59、ay to switch fluorescence inside cells is one of the main challenges in the development of fluorescent probes for bioimaging applications," raymo says. "our fluorescent switches can be operated in water efficiently, offering the opportunity to image biological samples with resolution at the nanometer level."fluorescent molecules are not water soluble; therefore raymo and his team created their system by embedding fluorescent molecules in synthetic water-so