[Aplicacoes] Estrutura Cristalina de Solidos
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[Aplicacoes] Estrutura Cristalina de Solidos

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Aula com Exemplos de Aplicações. ...

Aula com Exemplos de Aplicações.
Disciplina EMC5732 - Estrutura Cristalina de Solidos (/ Caracterização de Materiais 2), 2011/03, Prof. Ana Maria Maliska
Curso - Engenharia de Materiais
Departamento de Engenharia Mecânica
Universidade Federal de Santa Catarina

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[Aplicacoes] Estrutura Cristalina de Solidos [Aplicacoes] Estrutura Cristalina de Solidos Presentation Transcript

  • Estrutural
Cristalina
de
Sólidos:
 Aplicações Prof.
Ana
Maliska Daphiny
Po?maier,
posdoc 21‐set‐2011.
  • Nucleação
e
cristalização
da
SiO2 S A X S and D LS study of silica nanoparticle formation 5385 F ig. 5. ( A ) T ime evolution of the normalized scattering intensity, a r , in solutions with 640 and 1600 ppm Si O 2 at two di ere P(R) of scattered silica nanoparticles as a function of R and time (t = 10–55 min with time steps of 5 min) evaluated with G N O (1600 ppm Si O 2, IS = 0.05).( A ) F E G –SE M and (B) T E M photomicrograph of silica nanoparticles grown for 30 min in a solution with 1600 ppm Si O 2 and IS of) C ryo-T E M photomicrograph of silica nanoparticles quenched after 1.5 h from a solution with 1600 ppm Si O 2 and IS of 0.05.ison of particle diameters obtained from S A X S, D LS and T E M .pm) IS T ime (h) Particle diameter (nm) S A X Sa D LS TEM 0.02 1 5.8 4.6 ± 1.0 3.1 ± 0.4 2 6.7 4.7 ± 1.1 3.3 ± 0.4 0.11 1 7.0 — — 2 7.7 — 4.5 ± 0.7 0.22 1 7.2 5.8 ± 1.9 5.2 ± 0.9 2 8.0 8.0 ± 5.0 3.6 ± 0.5 0.05 1 6.9 8.7 ± 2.2 — 1.5 7.2b 10.1 ± 3.1 6.1 ± 1.1c b 2 7.5 9.6 ± 1.8 — 0.11 1 7.6 9.9 ± 3.5 5.4 ± 0.5 2 7.9 A ggregation — 0.22 0.5 G rowth of silica nanoparticles in solutions with varying [Si O ] and 5.1 as0.6 F ig. 6. 7.5 8.0 ± 1.0 IS ± determined by D LS. T he arrow indicates the 2 D.J.
Tobler,
S.Shaw
,
L.G.
Benning
“QuanTficaTon
of
iniTal
steps
of
nucleaTon
and
growth
of
silica
nanoparTcles:
An
in‐situ
SAXS
and
 1 7.9 A ggregation 6.7 ± 0.9 aggregation for solutions with 1600 ppm Si O 2 and IS of 0.22 (% errors are average values). DLS
study”
Geochimica
et
Cosmochimica
Acta
73
(2009)
5377–5393A ggregation 2 7.9 —r of S A X S <3%.
  • g the next bestmonds, is not the only element that is to hardness. Boron and nitrogen also high pressure and temperature, but theThey areat the hardest natural form of carbon beauty. first the ESRF as the densest material A
procura
da
melhor
coisa
depois
dos
 trong, short chemical bonds. In 1956 experiments failed. The scientists soonand are highly valued by industry for known noticed (Dubrovinskaia et al. 2005). sts combined boron and nitrogen to that there was a small portion of the structure Results showed that the A DNRs’ density isafter diamonds cubic boron nitride (cBN), which has this property. Industrial uses include cutting, that was already surprisingly super-hard at greater than that of diamond by 0.2–0.4%used as an alternative for synthetic drilling, grindingand is 11% less compressible. The combination ambient conditions. The team then decided and polishing. However,ess of diamond. Diamantes nds. However, it only has half of the am from the Institute for Superhard to isolate the small particle, compress it andfew draw backs: diamonds strongly characterise it. there are a of the hardness of the A DNRs and its chemical stability could make it a potential material resist heating and as soon as they are in The results proved that, in accordance for machining hard materials, grinding ISTO CKPH OTO.CO M ials in Ukraine, together with scientists with previous theoretical predictions, contact with a metal, they allywell as for use asis and polishing, as with it. This anvils in he University of Paris, the University of why researchers scientificpursuitlike diamond anvil cells and crystalline carbon nitrides exhibit exceptional are in devices of substitutesuth (G ermany) and the ESRF, managed multi-anvil presses. compressibility behaviour. In for diamonds with a better conductivity and addition,mbine carbon, boron and nitrogen in despite the usual considerations, the team A nother new material that is attracting aterial in 2001. The result, cubic BC 2 N, demonstrated that there is no need more for severe to temperature andthe super-hard resistance the interest of industry is corrosion. mpound that is half way bet ween and expensive pressure and temperature To create new aggregated boron nitride nanocomposite materials, scientists focus nd and boron nitride in composition. on the periodic table. C), synthesised by the same team and conditions to elaborate low-compressibility, (ABNN Carbon, the source Ap am applied a pressure of 18 GPa covalent materials (Goglio et al. 2009). tested at the Swiss Norwegian Beamline at mperatures above 2200 K, w hich of diamonds, is not ESRF (Dubrovinskaia et that is ABNN C The dow nside of this story, and most of the the the only element al. 2007). red the appearance of a ne w phase. stories linked to creating new materials, hardness. Boron and nitrogen bulk material hig linked to is that is the first non-carbon-based alsough the ne w compound is not as hard their production is still at a very small scale. short chemical hardness approaching that exp form strong, with a value of bonds. In 1956mond, it is harder than its predecessor, In most cases, w hen scientists try to increase of single crystal and polycrystalline diamond scientists combined boron and nitrogen to thaDespite the fact that it was synthesised the production, the material decomposes, and A DNRs. ABNN C also has unusually highyears ago, its usepaper on diamond ishighly in and w hich means that the phases are verycubic boron nitride (cBN), which resistance, as tha Apart from the in jewellery, BC 2 N is still valued widely used in industry. create fragile. fracture toughness and wear hasmelight (Solozhenko et al. 2001). Proof However, the creation of new hard materials an well as high thermal stability (above 1600 K in been used as alternative for synthetic am are the 150 and temperature, butit has had(Dubrovinskaia et densest form of carbon and researchers high pressure citations that the first at the ESRFis progressing swiftly – as the air), making it an exceptional the diamonds. However, it only has half of superabrasive. to i experiments failed. The scientists soon noticed al. 2005).w hichthere wasinsmall portion of the structure that were a 2008. Results showed that the A DNRs’ density is it is only a question of generally comment that M Capellas that was already surprisingly super-hard at hardness of in time until new materials can be synthesised greater than that of diamond by 0.2–0.4% diamond. cha ambient conditions. The team then decidedap,to isolate the small particle, compress it and super-hard material and is 11% less compressible. The combination large quantities. of the hardness of the A DNRs and its chemical A team from the Institute for Superhard References Tnancial cost of characterise it. developing these new stability could make it a potential material The results proved that, in accordance for machining hard materials, grinding M aterials in Ukraine, together with scientists Lett.wit N Dubrovinskaia et al. 2005 Appl. Phys. alswith a mass-production rate will and polishing, as well as forinterest in at previous theoretical predictions, Industrial use as anvils 87 083106.mine whether they will be used in crystalline carbon nitrides exhibit exceptional anvil University of Bayreuth University of Paris, the University of Lett. scientific devices like diamond the cells and A team from from the N Dubrovinskaia et al. 2007 Appl. Phys. cry ry. despite the usual considerations, the team for an A notherhas material that is attracting to raiseBayreuth (G ermany) and the ESRF, managed com compressibility behaviour. In addition, multi-anvil presses. A potentially cheap solution new already managed the interest 90 101912. demonstratedis the result of research the interestof industry is the super-hardard material that there is no need for severe and expensive pressure and temperature to combine carbon, boron and nitrogen in of industry in their patented Aggregated aggregated boron nitride nanocomposite G Goglio et al. 2009 Diamond & Related desby the University oflow-compressibility, the conditions to elaborate Bordeaux and (ABNN C), synthesised by the same team andDNRs), a new material in 2001. The 627–631.cubic BC N, Diamond Nanorods (A one material Materials 18 result, dem synthesised in 2005 based on bulk samples sity of Clermont-Ferrand (France). tested at the Swiss Norwegian Beamline at covalent materials (Goglio et al. 2009). 2 V L Solozhenko et al. 2001 Appl. Phys. Lett. The dow nside of this story, and most of the the ESRF (Dubrovinskaia et al. 2007). ABNN C of nanocrystalline diamond and identified team studied creating new materials, is that is the first non-carbon-based bulk material stories linked to a carbon nitride under is a compound that is half way bet ween 78 1385–1387. and their production is still at a very small scale. with a value of hardness approaching that diamond and boron nitride in composition. con
  • tor, and vice versa splacements leading to the newetallisation takes place due toygen, are insulating at room temperature, but if you put themf the band gap that occurs with to conducto O2,
Na
e
Li,
Isolante‐Condutor? oxygen of the that don’t have electrical resistance. The other way erials lattice, which evolves intocture withtakes place with of ic event, the dissociation elements such as lithium or sodium. ing to c oxygen can transform even Many elements, such as tities. understand why and how these events happen. under pressure you get materia e 250 GPa, theoreticians predict L LUNDEG A ARD ons to an atomic metal. “This is enge for ID27, providing that the , o round, which is a more exotic eood quality single crystals at these Composite diffraction image: data from the one of the phases of sodium with 90 atoms in unit cell. utexplains Mohamed Mezouar, the Scientists are slowly managing t arge of the beamline. phases are reached in a very small region of “Sodium pressure–temperature domain, in the vicinity s of the sodium’s melting curve minimum.meffect from oxygen under Slight changes in pressure or temperature set y s place when metals, such as and lithium Oxygen is the third most abundant which are very off new transitions, some of element thium, become compressed. in the universe by mass,had never been observed in any complex and after hydrogen and long to the group of lighterwsified as “simple metals”, are actually other element before. One of these structures helium. More than 20% than 500 atoms in the air cell. contains more of the volume of unit they have simple crystal and uctures. However, under o insulating when consists of oxygen. Despite its predominance,on The team carried out their experiments its behaviourID27 using single-crystal diffraction. They under pressure is still not clear to adopt different physical states.o separate teams (Ma et al. under pressure” identified the lattice parameters and the researchers. Above of pressure of 96phases. The a number atoms of all seven GPa (about a quarter of the pressure inside light on theoretical results for sodium shed the Earth’s t tsuoka et al. 2009) discoveredand lithium are actually e under ordinary conditions sodium adoptsoxygen has shown a metallic phase,other core), a models that predict bizarre states for but se Composite diffraction image: data from the one of the phases of sodium with 90 atoms in unit cell. en under pressure and that straightforward crystal structure, but under materials, such as hydrogen. Na
‐
7
fases!
‐
pressao/temperaturasmall region of highscientists have only recently determined the emes transparent, using Raman phases are reached in a very therefore high pressure, and density M Capellas “Sodiumy and the Advanced Photon pressure–temperature domain, in the vicinity of the metal, things change. For starters, of the sodium’s melting curve minimum. changes in its crystalline structure. cago (US) (Ma et al. 2009). the melting temperature of sodium is lower from the Commissariat à l’Energie Slight changes in pressure or temperature set A team References and lithium onering experimental work off new transitions, some of which are very complex andpressure (118 GPa) any E Gregoryanz et al. 2008 Science 320 1054. at high had never been observed in than atAtomique (France), the University of O ttawa ambient are actuallyodium under high pressure other element before. One of these structures contains more thanToday, a team from the University conditions. 500 atoms in the unit cell. Y Ma et al. 2009 Nature 458 182–185. (Canada) and the ESRF, clarified a standing insulating when ID27 Edinburgh (Gregoryanz et t the ESRF on the beamline ofThe team carried out their experiments on al. 2008) and T Matsuoka et al. 2009 Nature 458 186–189. years ago. It was known that using single-crystal diffraction. They debate on the Weck et al. 2009the 102 255503. identified the lattice parameters seven different crystalline the ESRF found that and the G transition of PRL element from . under pressure” number of atoms of all seven phases. The
  • Focus on: extreme conditionsrthCondições
Extremas
–
centro
da
terra to its surface from the centre Take a trip The Earth is still an enigma. The Earth’s layersN ASA G O DDARD SPA CE FLIG HT CENTER (N ASA- GSF C) But the ESRF is helping to Layer Distance from surface (km) Pressure (GPa) Crust 0–35 <1 demystify our Temperature (ºC) planet, its 200–600 Upper mantle 35–660 composition and inner activity. 1–25 600–1600 Lower mantle 660–2890 25–136 1600–4000 Outer core 2890–5150 136–330 believe that4400–6100 by Geologists Earth was struck a planet the size of Mars about 4.5 billion Inner core 5150–6360 330–360 The impact 6100K (±500K) years ago. led to the formation of our satellite, the M oon and melted most of the planet’s rocks, creating its core, as the metallic iron bet ween the rocks sank subsequently infer what the conditions must and anisotropy of magnesium- and iron- towards the centre. Therefore, iron is of major Fe
(35%)
+
Ni
+
S,
Si,
C,
O be deep in the Earth. At the ESRF, a team from the Institut de containing silicate perovskites on ID24 and interest in the scientific community. Despite ID27. It also investigated post-perovskite it being physically impossible to access the Minéralogie et de Physique des Milieux of the Earth’s core, high-pressure experiments at same material, which occurs when synchrotron sources can provide major clues Condensés at the University of Paris studied pressure increases in the and other materials lower mantle. The the sound velocity in solid iron alloyed with Fe‐FeS
=
Fe3S
(1000
K) about the role that iron idea was to the core. play in determine whether the phase light elements using high-resolution inelastic transitions in perovskite are at the origin The Earth’s core is divided into t wo zones: the outer core, which is liquid, and the inner X-ray scattering on ID28 (Badro et al. 2007). It of seismic discontinuities in the zone. The core, which is solid. The main component of ruled out sulphur as a possible light element in the core and proposed that the inner core Fel
‐
2.8%Si
+
5.3%O2 post-perovskite transition could alsothe the core is iron, which is crystallised in provide information about the know this because the inner core. Scientists temperature variations is made of iron, silicon (2.3% w t) and traces of the speed of sound the time of ESRFnews going D’’ layer. At through the core (the velocity at which seismic waves travel across it) and the of oxygen. If extrapolated to the liquid state, to press, a very promising paperthose seen in density of the core are similar to addressing the team suggests that the outer core could these questionspressures the temperatures. On iron at high was in and submission process silicate‐perovskites
‐>
post‐perovskites contain 2.8% w t silicon and 5.3% w t oxygen. Silicon and oxygen can be partly dissolved in (A ndraultof that, iron is sufficiently abundant in the top et al. 2009). It is crucial to make upperovskites with iron, universe to study for approximately 35% of the mass of the planet present in the core. iron, so the total amount of light elements in even if itHowever, iron is not alone in the core. The is technically more complicated, the inner core would be 2.5% w t, and 8% w t because iron is a transition element that can core should contain ~10 % w t of nickel and, in the outer core. change its importantly, seismology shows that more electronic structure under pressure both parts of the core are too light to be pure, M ore recently, the team studied silicon and, as a consequence, the way that could dense iron–nickel alloy. The outer core the bearing iron–nickel alloys and compared them Earth’s interior% w t of lighter elements, while have 6–10 behaves. Researchers from with pure iron. The results, which have been the UniversitycoreBayreuth carried outThe the inner of would contain 2–3% w t. nuclear submitted for publication, show a model for resonance experimentspotentially mix with iron candidates that could on ID18 and ID27, are sulphur, silicon, carbon and oxygen. the contribution of silicon and nickel to the as well as at the Advanced Photon Source, Earth’s inner core. on lower-mantle perovskites. The goal was The case of sulphur to measure the spin-state transitionsthe iron It is quite likely that sulphur is present in of deepest sector of the Earth because meteorites On the boundaries between the core and in the perovskite. Surprisingly, they found a contain this element abundantly. A team from the mantle: the weird D’’ layer stable the University of Paris and the University of the intermediate spin state throughout The core still has many surprises in store, lower mantle (McCammoniset al. 2008). Clermont-Ferrand (France) studying how
  • histication. The researchers ut have never clearly their work will Research light on Scientific and shed ied histone-binding of d their role. Now, an nal team of scientists potential problems in sperm Organization, the University of California (US), the University Proteína
ligada
à
evolução
do
esperma,
 ,that there maythat it binds most finding be a reason for the presence ngly on goldhistone with t wo to a grain developmentOntario and the of Western and are now looking University of Saskatchewan at the (both Canada), this protein plays in role that Martin-Luther- acteriaolecular crystallography unveils (US), SCK. bacteria
para
formar
ouro of thatparticular kind (in this a the metal- “A number of years ago ered human Nebraska-Lincoln University male infertility. Universität (Germany), of nked groups) and, image of1aµm metalliduranssperm the APS (US) and , acetyl to the evolution of CEN (Belgium), acterium durans occurred on gold A TEM contrary C. the ESRF (France). xpectations, usesultrathinone containingReference the first direct evidence m t wo sites in Australia. just section a This is place on ID23-1 and ID23-2. ISTO CKPH OTO.CO M einSouth Wales and dogold nanoparticle (in the middle).orinièrefewto a arerare and precious domain to re 3500 km apart, in y. New so. J“smallcould only obtaincycling of actively involved We M in Brdtbacteria al. 2009 Nature 461 that a crystals of thebound et 664–668. at the he key experiments took which pushes the Petosa, metals, such as gold. These results doubly tagged ligand,” explains Queensland, so when gold toxicity, Carlo researcher the same organism on bacterium to induce oxidative open the door to the production Institut de Biologie Structurale in Grenoble and member of the m both sites we thought s stress and metal resistance team. “ W hat’s more, the crystals “The discovery of a of biosensors: ere onto something. clusters as well as an as yet initially appeared to be unusable operon means that gold-specific because they were highly wonder why these uncharacterised gold-specific we can now start to develop gold- ESRF gets good ofHowever,to Bacterium helps to fo m disordered internally. s live in this particular gene cluster in order to defend specific biosensors, which will help exposing the edges a crystal ent. The results of this marks from studyX-rays explorers to find new gold a grazing beam of its cellular integrity. This leads to thinnest tips gave a mineral revealed that the Society The American Physical It i Australian scientists have found nt to their involvement active biochemically mediated well-ordered deposits. To achieve this we need REITH ET AL, PN AS 5–9 O CTOBER 2009 diffraction that the bacterium Cupriavidus has recently completed the study pattern. te July 2010 for reconstruction improvements facilitate the ve detoxification of gold reduction of gold complexes to Internationalfurther characterise the gold- nano-particulate, metallic data “Access to Major to Using the microfocused beam at metallidurans catalyses the X-ray and Neutron Scattering collect biomineralisation of gold ID23-2, we could enough s leading(the only cell in our body that swims) racing to get to the egg. gold,from a single crystaloperon on a genomic as specific to solve th Sperm to formation to the same port. The renewed ominerals”, explains alignment of the sample and the Facilities”, which explores by transforming toxic gold which may contribute to thetheaccess to light as proteomic level. If funding how scientists’ structure.” well compounds to their metallic form of su that act code to direct of the research nuggets. sources has been believe that active cellular mechanism. The researchers h, leader as achromatin structure. grow th of gold extra levelneutron their work willfor this research is granted I believe the discovery of an and of using 24 will comprise t wo stations, changes in eng at the University to the Different proteins bind of A FM-tip with respect to the X-ray sophistication. The researchers not only in the US but light onResearchers reported the evolving shed studied histone-binding of internationally. The final in sperm produce a on gold For this study scientists potential problems we presence of bacteria functioning also that can sc Ad hich will be commissioned beam. It enables the accurate Brdt, finding that it binds report most development and are now looking tags, the combination of which combined synchrotron has been posted onbiosensor within have never clearly surfaces but 3–5 years,” Australia). the code. Until now, deciphers strongly to a histone withthe APS website at role w.aps. protein plays in their role. Now, an t wo at the w w that this Sc elucidated Or eriments showed these scientists thought that tags of a particular kind (in this org/programs/international/ concludes Reith. techniques at the ESRF and human male infertility. international team of scientists 2011. Current planning is positioning of a pre-chosen Ca tallidurans rapidly or more the Advanced Photon Source proteins bind using one case, acetyl groups) and, resources/facilities.cfm. It contrary has found that there may be a of e modular “domains”, with each to expectations, uses justpositions theReference leader in one ESRF as the Un tes toxic gold complexes (APS), and molecular microbialorinière etReference 461 reason on goldpresence biological for the reopen the first branch of domain docking to just one tag. nanostructure in the focal beam protein domain to do so. synchrotron J M ution prepared in reports techniques to understand the However, this new study The key experiments took decade. facilities for the next Nature bacteria al. 2009 of these 664–668. F Reith et al. 2009 PN AS. grain surfaces. “A number of years ago (b Un e renewed beamline in the user groupsspot that can currently be as small his process promotes biomineralisation in bacteria. 32 facilities and across the globe For the study, resistant bacterium doi:10.1073/pnas.0904583106. we discovered that the metal- 1 µm of CE
  • of Kiel (Germany) and the stable, to room temperature. found a rapid synthesis of an Because the researchers discovered thathis well studied material.2 O 8 had been thought to be Síntese
de
Materiais
“NTE”
 this NTE material can be synthesised in this way, it means that lengthy precursor routes ght: viewed from the three fold axis. ZrO6 octahedra is shown in green, careful thermal transformations mayall temperatures and, unlike requiring MoO4 tetrahedra inon: time-resolved studies Focus yellow. it had not been possible to no longer be necessary.follow the synthesisrectly from the constituent ow. John Evans, leader of the team, from Durham University, comments thatmaterial as it happenshers noticed in their lab that “the use of extremely rapid quantitativeable to form the supposedly powder diffraction at the ESRF was crucialbic phase by firing the to unravelling this chemistry and similar at NTE materials expand anisotropically, thetechniques could X-rays of the significant insight in desM osthigh temperatures high flux and high-energy provide few secondscubic crystal structure the beamline, areas of materials synthesis”. othera unique real-time insight into the followed by rapid them with and the FRELO N camera provided (differently in all dimensions). However, for materials with a M Capellase team used the ID11 beamlineall synthesis of the new material. This camera was symmetry forces them to contract equally insitu minimise – isotropicsuch as micro-cracking short timescales over which the different dimensions to experiments contraction. This helps particularly important due to the extremely problems to monitor the Two as cycling. Reference e metal oxides views of ZrMo O from different angles. Right: viewed from the three fold axis. ZrO octahedra is shown in green, MoO tetrahedra in yellow. during repeated thermalthey reacted phases appeared. The most famous cubic NTE material The reaction took place extremely quickly 2 8 6 4 atures, using the(ZrW 2 O 8), which is zirconium tungstate technique at elevated temperatures with ZrM o 2 O 8 J. Am. Chem. Soc. J E Readman et al. 2009 Scientists follow the synthesisraction. They benefited from contracts over a temperature range of 0.3–1050 K. However, at about 450 K, it doi:10.1021/ja907648z. formation occurring within seconds at ~1360–1400 K. Reaction occurs via the of an NTE material as it happens suffers a transition from an ordered structure to a disordered one, and above 0.2 GPa of melting of M o O 3 , the formation of trigonal ZrM o 2 O 8 and then the formation of cubic pressure it becomes significantly denser and A team of European loses NTE properties. These transitions could ZrM o 2 O 8 . The reaction is complete within a few NTEinmaterialsand the material can be flux and high-energy X-rays of the M ost seconds expand anisotropically, (differently all dimensions). However, for the high beamline, and the FRELO N camera provided 9 limit the industrial uses for this material. has, scientists and the ESRF quenchedafromcrystal structure the conditions, a unique real-time insight into the materials with cubic the reaction them with Researchers from Durham University (UK), where it –appears contract thermodynamically new material.the extremelywas symmetry forces them to to be equally in all synthesis of the This camera for the first time, enabled dimensions isotropic contraction. This helps particularly important due to
  • Células
Combusoveis
Poliméricas A Mercedes Benz Citaro London bus running on fuel cells. This kind of bus was first used in 2004 in the English capital. Several cities around the world already use fuel cells in their buses. Take a look inside a fuel cell solid polymer distributor The fuel cell uses hydrogen and oxygen to electrolyte plate create electricity. The reaction occurs in H2 a structure consisting of two electrodes cathode (the anode and the cathode) separated by anode the electrolyte membrane, which lets the ions through. The electrodes activate the H+ hydrogen oxidation as well as the oxygen O2 (air) reduction. – current In the case of a proton-exchange collector study, one can conclude that this membrane, the hydrogen at the anode is C O M M U N IC ATI O N H 2O MEA dissociated into protons and electrons. At thehe correlation between evenelectricity + minimal cathode, the oxygen, electrons and protons the hydration degree, as can heatseen in be recombine to form water. red circles in Figure 3.study consisted of a vertical scan of the through an external circuit, and in this way executed collecting the diffraction thickness. The researchers took a sequence provide the electric power. To effectively of diffraction patterns that showed the waterprimary X-ray beam with a transversal be changes induced by changes of the working transport protons, the membrane needs to 100 mm (horizontal). humidified. However, an excess of water may conditions. In this way, the variations in theeady conditions (after about the consequent degree of water could be correlated with the produce cathode flooding and 2 h, at the of decreaseA), the cell performances. accom- 100 m of stratigraphy was cell voltage. Several groups are studying membranes The team also carried out spacially position at which the primary beam resolved experiments to determine the water like Nafion at the ESRF to monitor in situ rface changes that itcatalyst at the anode the with the Pt goes through during the distribution along the membrane thickness. vely vertically shifted, in steps of the aging oxidation and reduction processes, 7 mm, This helped the scientists to elucidate in atof its nanostructure, or its hydration degree the cathode side was reached, with detail the complex water dynamics occurring as a function of the operative electrochemical in the active component of a running fuelon at each step. Since the membrane parameters. The scientists use beamlines such cell. Valerio Rossi Albertini, a member of the chas ID02, ID13, ID15 andthe water content sampling allowed BM26. team, explains that: “the water dynamics k of Recently, a team from the Istituto di 21 different ‘‘slices’’. The main in the membrane of a fuel cell is one of the patterns of theMateria in Rome, University Struttura della collected sequence are main aspects in the use of such devices for ˚ 1 (see the insert of Fig. of Camerino (Italy), and the ESRF measuredues 0.5 and 5 A locomotion. The variable working conditions, the water in a running fuel-cell membrane for instance because of the request ofmembrane layer by layer from the H 2 in real-life conditions. For this experiment, rapid increase of power supply during thelectrode, the trend can be qualitatively they used the high-energy beamline ID15B acceleration of a vehicle, may produce heand determined the overall presence of water initial patterns of the sequence, dysfunctions and electrochemical instabilities C.
C.
de
Araujo,
K.
D.
Kreuer,
M.
Schuster,
G.
Portale,
H.
Mendil‐Jakani,
G.
Gebel
and
J.
Maier
”Poly(p‐phenylene
sulfone)s
with
high
ion
exchange
 and the hydration degree the H layer of the Figureto water overproduction. Conversely, an distribution in the PEM in the membrane close to in each 2 anode, due 4. Space-resolved study of the water steady conditions: water the supplyingthe membrane as a function of the insufficient hydration of content of gases capacity:
ionomers
with
unique
microstructural
and
transport
features”
Phys.
Chem.
Chem.
Phys.,
2009,
11,
3305‐3312. membrane with the highest precision ever.increase of the main-peak height (at To observe the overall amount of water vertical scan,releaseanode to cathode,current or the heat from due to the proton and reverse. The diffraction patterns aindecrease of the team carried out the the membrane, the intensity in corresponding to may two scanning sequences (from the H 2 to the O 2 in the membrane the result in its drying. V.
Rossi
AlberTni,
B.
Paci,
F.Nobili,

R.
Marassi,
M.
Di
Michiel

“Time/Space‐Resolved
Studies
of
the
Nafion
Membrane
HydraTon
Profile
in
a
 er the experiment by irradiatingthe trend is the first five patterns, a Nafion 117 electrode and developedare ID15 can help the insert. The method reverse) at reported in in Running
Fuel
Cell”
Advanced
Materials
Volume
21,
Issue
5,
pages
578–583,
February
2,
2009. itymembrane, main 140 µm thick, with an X-ray understanding and describing such complex of the about peak progressively ope. The scanning sequence was to its beam with a cross-section equivalent then tion) dynamics.”(horizontal), which allowed the hydration degree water 100 mm
  • structure before and after the “breathing” is produced by industry within a complex process, using X-ray powder diffraction. mixture of CO 2 , CH 4 , CO, H 2S, CH 4 ..., one has Armazenando
gases
e
energia,

 Today the team is working on the use of to capture CO 2 with a high selectivity versus M OFs for their separation properties (gases, the other components. M OFs, with their liquids) as well as to develop biomedical tunable pore size, large sorption capacities,energy applications using non-toxic biodegradable good selectivity and easy regeneration, offer a for a greener future iron M OFs. nice alternative to zeolites or amines. projetando
as
baterias
de
Li
do
futuro ng gases: a key for a greener futureore Industrial applications on hydrogen storage are already under way. Researchers from the company BASF showed recently that, compared with pressurising an empty Experiments at the ESRF allowed the team to study the breathing of the solid upon adsorption. By combining diffraction with Raman spectroscopy and computer has lop container with hydrogen, if the M OFs are simulations, they evaluated the “breathing”gen added they increasingly take up higher pattern of the MILs. They found that theheul tool amounts of hydrogen with less pressure. coadsorption of CO 2 and CH 4 leads to a eld. to design and build different structures that similar breathing pattern of MIL-53 (Cr) as ISTO CKPH OTO.CO M INSTITUT L AVOISIER ydrogen could take up molecules of a different size. Sequestration of toxic gases with pure CO 2 .nergy They have developed a variety of MILs (for gen is le, it f any CO 2 and CH 4 are t wo types of gases that For the future, scientists find potential in the t does Material Institut Lavoisier), including the are currently damaging our planet, so their flexibility of some MILs: “ One could imagineing the lithium-ion ges, its the metal terephthalate MIL-101 back in 2005, elimination would be another step towards a benefiting from the flexibility by applying ture he a structure with very large internal pores cleaner environment. CH 4 is not adsorbed by a mechanical pressure to make the MIL-53 gas ot of (a diameter of 3.4 nm) and surface area M OFs as well as CO 2 , but, on the other hand, solid close its pores and desorb gas mixtures,unityes of the future store y by (5900 m 2 g –1). This MIL is still studied today and both of these gases are adsorbed at room for an easier regeneration without the need it into tested for the purification of hydrogen using temperature, unlike hydrogen. for thermal or vacuum treatments,” explains s to uent uture mixtures of greenhouse gases (CO 2 and CH 4). A team led by the University of Aix- Christian Serre of the Institut Lavoisier. M ore recently, together with ayears later, the team joined forces with Two group at the A nother promising way of storing hydrogen, r the gas hydrogen-release temperatures as well. more Metal-organic frameworks Left: hydrogen, a simple element that has given hopeCapellas M arseille in collaboration with the team M to scientists in the quest for a more tions. be University of A arhus (Denmark), they prepared as well as capturing gases such as CO , is the the University ofOFs aremetal-organicto publish its results and characterised novel anion-substituted 2 Rennes frameworks (M OF). so-called environmentallyLavoisier,world. Above: The MIL-53 is a very flexible metal-organic framework. from the Institut friendly together with ISTO CKPH OTO.CO M IFP, the University of Caen, of the structure (large pore form); on the right, the structure On the left, the dried form the University ydrogen modifications of these materials. M extended crystalline net works ds or fied, and on new (BH ) by a frameworks:open pores hybrid made of metal/oxide groups heldMIL-88 A , B, C The joint team also prepared novel materials by cation substitution, e.g. LiZn by organic linkers, with large, together References (narrow pore form)the ESRF (all in France), after adsorption of various guests,Arnbjerg et al. 2009 Chem. Mater. 21 L M such as carbon dioxide or water. 2 4 5 ms are reaction of LiBH and ZnCl . The idea was to that make them ideal for storing gases. Their introduce a less electropositive metal (Zn) in the pore size and shape canthese new structures and D. The peculiarity of of M ontpellier and 4 2 be easily tuned certain structure of the borohydride. “ We discovered a by changing either the organic ligands or on new compounds,that they could sustain a reversible huge is which store large amounts of have other applications, such as sensors in much unexpected structural chemistry of these the metallic clusters. They can potentially recently studied MIL-53 (Cr) for the 5772–5782. without breaking bonds and retaining the It is necessary to separate the t wo gases rogen increasealreadyvolume. It these materialsprocesses. The 85% of in in catalysis and ranged from separation of mixtures of CO 2 and CH 4 at T Devic et al. 2010 J. Am. Chem. Soc. 132 etrol, hydrogen and release it at low temperatures of nanotechnology, and they are already used orage some 80–100 °C,” explains Yaroslav Filinchuk, ion-exchange ee of BM1. He continues: “ We have advantages of in comparison crystallinity of the materials. The reverse as part of the capture, transportation andhydrides, show interesting structural, chemical and to an unprecedented 230% . Such e their size up density and the hydrogen storage is governed proven that the novel modified borohydrides with the hydrides are that they have a low ambient temperatures. MIL-53 (Cr) changes 1127–1136. process was achieved by heating the solvated sequestration of CO 2 . For this it is required materials, as a large the hydrogen in they can release expansion in crystallineto study reaction. Scientists come to the ESRF materials had its pore size and shape in response to Y Filinchuk et al. 2008 Angew. Chem. Int. Ed.mides physical properties.” Scientists aim for unstable by a physisorption process and not a redox alanates mild conditions, whereas if they are too stable, crystalline structures of different M OFs using form, which ended in the material closing to obtain a pure CO 2 (>95%) prior to its not been observedID31 and BM1,diffraction on beamlines ESRF to they require a lot of heat to release it. of reality, for example in Japan and Germany, ferent Hydrogen-fuelled buses are already a such as before. This reversible mostly X-ray powder although they have adsorption of molecules such asporosity. pores with almost no accessible CO 2 and 47 529–532. in former gas or oil reservoirs storage, either ter, fuel generalisapplicationtime away, despitenew regular user group ESRF, isdomain,to the function “breathing”the also nused microdiffraction theID13.and action is the in this at team from similar HThe scientists came to the ESRF to study the 2 O, going from a narrow-pore to a large- or other geological areas of interest.57 732–738. Y Filinchuk et al. 2009 Acta Mater. As CO 1. A stable but of hydrogen as a A activeH ), in cars still some of 2 is Hamon et al. 2009 J. Am. Chem. Soc. L produced by industry within a complex 131ngofto fact that the of lungs in humans: Lavoisier in Versailles (France). size when they they have managed grow in pore form.before and after the “breathing” However, apolar molecules like 4 2 ts automobile industry is starting to the Institut igh ryday associate itself with academic research. As if it was a M eccano, structure inhaling and go back to their original size CH 4 don’tusing X-rayhave any diffraction. process, normally powder effect. The 17490–17499. mixture of CO 2 , CH 4 , CO, H 2S, CH 4 ..., one has d as M arch 2010 ESRFnewsdue to when exhaling. The lungs only expand, breathingthe team is working onFthe the of Today behaviour of the M O in use P L Llewellyn et al. 2006 Angew. Chem. Int. Ed. to capture CO 2 with a high selectivity versusolyte however, by approximately 40% . 17/2/10 14:18:08 presence of gasseparationis not yet clear to M OFs for their mixtures properties (gases, 45 7751–7754. the other components. M OFs, with theirn Various solvents (normally water, but also scientists, especially develop biomedical a liquids) as well as to w hen they contain tunable poreksize, large sorption capacities, Ed. D Ravnsb æ et al. 2009 Angew. Chem. Int. alcohols) entering the materials open their component that provokes breathing and applications using non-toxic biodegradable 48 6659–6663. good selectivity and easy regeneration, offer a ted cavities. This makes the structures grow, Lithium batteries are widely used in mobile communication devices, such as PDAsone that doesn’t, like CO 2 and CH 4 . anotherOFs. iron M or smartphones. nice alternative to zeolites or315 1828–1831. C Serre et al. 2007 Science amines.hen Industrial applications on hydrogen Experiments at the ESRF allowed the
  • IMPM C) glassthe ESRF, has studied had a predominant role types of and opacifiers, antimonate compounds haventhesised nanocrystals 1a) 1c)ptian opaque a predominant rolehistory. They are found from the nds have had glasses from thethroughout 1a)out history. They areMuseum. glass technology in M esopotamiaeum and the Britishorigins of the found from Sb Si D VIGEARS C2RM F e 18th dynasty, glass objects ID21 ESRF until modern times. However, both their f glass technology in M esopotamia Egipcios
tornaram
os
vidros
opacos 10 µmF hastimes. However, bothglassin ancient Egypt, contrary to belief, e or shown that craftsmendern translucent coloured their and provenance remain obscure. Sb Si D VIGEARS C2RM F technologyding synthesised calcium-antimonate crystals to a translucent dicated to the upper classes, who gy and provenance remain obscure. questions, the researchers To answer these Ca s perfume questions, the researchers its non-transparent look. re nanocrystals and wer these or cosmeticgive thean original strategy focused on the developed glass containers. Ca devitrification crysted te,an originalturquoisefocused on of the crystals and the vitreous blue and strategy glasses investigation the ed by calcium-antimonate vitreous and the crystals Feature devitrification crystal D BA G AULT C2RM F D BA G AULT C2RM F tion of the crystals matrices. For the first time they reproduced a vitreous matrix. Among the vitreous matrixmade opaque glasses en. the first time they reproduced For opacified glass by the addition of crystals indes of glass opacifiers, of crystals in glass by the addition antimonate 1b) 2) the laboratory under controlled conditions. 1b) 1c) 2) calcium antimonate atory had a predominant role have under controlled conditions. y crystal They also compared these synthetic glasses 1a) Figure 1 (top and bottom left and centre): opaque, coloured glass fhesised nanocrystals omohistory. They are found from the compared these synthetic glasses Figure 1 (top and bottom left and centre): opaque, coloured glass from the 18th Egyptianass technology in Mto ancient Egyptian glasses using appropriate (inventory number AF2622). b) Shards (inventory numbers AF12707 dynasty. a) Small amphorae (inventory number AF2622). b) Shards n ID21 ESRF esopotamiant Egyptian glasses using appropriate dynasty. a) Small amphorae 10 µm micro and nanoanalyticalAF13175). c) Blue and turquoise necklace (inventory number E2341). These (inventory number E2 techniques and AF13175). c) Blue and turquoise necklace objects come Sb Si D VIGEARS C2RM Fn times. However, both their d nanoanalytical techniques and died nevermaterial: Egypt, contrary to belief, and provenance type of in ancient shown that craftsmened before on thisremain obscure. used before onfrom type of material: this the Egyptian Antiquities Department of the Louvre Museum. Figure 2 (bottom right): micro from the Egyptian Antiquities Department of the Louvre Museum. sion electron microscopy at the electron microscopy at the transmission rynthesised calcium-antimonate crystals to a translucent these questions, the researchers X-ray fluorescence (µ-XRF) analysis of a polished fragment of Egyptian glass (sample c). µ-XRF Egyp X-ray fluorescence (µ-XRF) analysis of a polished fragment of Caand micro X-ray absorption near-edge X-ray absorption near-edge (red), calcium (green) antimony (red), calcium (green) 72 × 36 µm2, (blu IMPM C and micro elemental maps of antimony elemental maps of and silicon and silicon nocrystals andandspectroscopy atnon-transparent look. × 0.5 µm the pixel size is is 1.1 × 0.3 µm2.(blue). The map size is sn original strategy focused on the give the glass its who the ID21. The synchrotron-basedID21. The synchrotron-based 2 and the probe size 0.5 × 0.5 µm and the probe size is 1.1 × 0.3 µm .n of at crystals copy the vitreous the pixel size is 0.5 devitrification2 crystal 2ners. r the first time to bemeasurements proved to be well suited ments proved they reproduced well suited vitreous matrix D BA G AULT C2RM F D BA G AULT C2RM F ective measure of of the selective measure ofopacifiers are nanocrystals. to antimonyass by the addition thecrystals in stals these the antimony these opacifiers are nanocrystals. calcium antimonate calcium-antimon calcium-antimonate glass opacifiers were 1b) 2)nry under the vitreous matrix. state in the vitreous matrix. nate state in controlledoxidation conditions. This outcome made the researchersoutcome made synthetic compounds. These also synthetic co This also the researchers crystal findings y, combined with thentimony, combinedwant (top microstructure and want to opaque, coloured glass from the 18th Egyptian A mpared these synthetic glasses 1a) microstructure Figure 1 to investigate further andcentre): investigate further and try to 1c) with the and bottom left try to provide further evidence for the sophisticated provide further e hegyptian glasses using appropriate observations dynasty. a) Small crystalline phases conditions (inventory number conditions of and remarkable know-how of this ions and the crystalline phases and thereproduce the amphoraeµm the preparation AF2622). b) Shards (inventory numbers AF12707 and re of reproduce the chemistry the preparation chemistry ID21 ESRF ia 10ation, is one oftechniques and AF13175).parameters crystals. The of the key c) Blue and necklace (inventory numberWe believe that this work is the We b anoanalytical the key parameters is one of calcium-antimonate turquoise calcium-antimonate crystals. The These objects come civilisation. E2341). Sb Si D VIGEARS C2RM F re. researchers as identification, of civilisation.before on this typean indicator of the fromCathe an indicator of the ween 700 andof the Louvre Museum. for a complete reassessmentpoint fo hehers compounds were fired bet of material: researchers as Egyptian Antiquities Department used by the starting point Figure 2 (bottom right): micro compounds were fired bet ween 700 and startingntion process employed. the electron microscopy at the X-ray fluorescence (µ-XRF) analysis of a°Cthe 1–18 hours, depending on the glass not only of ancie opacification process employed. 1100 °C for 1–18 hours, depending on devitrification crystal 1100 forpolished fragment of of ancientglass (sample c). µ-XRF not only Egyptian Egyptian studies ow, scientists thought that ancient elemental maps of antimony (red), calcium (green) and silicon generally ofmap size is 72 × 36 µm2, us micro X-ray absorption near-edge case. Subsequently, they studied the nature, but more (blue). The high-temperature d Until now, scientists thought that ancient matrix case. Subsequently, they studied the nature, vitreous but more genera y at ID21. The n was made from in situ thecrystallographicantimonateµm2 and the probe size is 1.1 technologies used throughout antiquity,” says opaque glass synchrotron-based pixel size is 0.5 × 0.5 situ structure and oxidation of 2 × 0.3 µmand oxidation of . 1b) Egyptian opaque glass was made from in 2) calcium crystallographic structureLahlil, the technologies use nts proved1new study suited centre):this new study hasthe crystals obtained, and the the crystals obtained, main the ation. This to be well has refuted antimony on Sophia correspondent of the s. crystal on. dynasty. to what was thought,This results were very nanocrystals. antimony on calcium-antimonate and opacifiersSophia Lahlil, the crystallisation.opaque, coloured glass from the 18th Egyptian refuted this s Figure (top and bottom left and ive measurea)of the assumption.number AF2622). b) what(inventory numbersto the analysis on the very close to the analysis on the ate Contrary Small amphorae (inventory antimony these opacifiers are close AF12707 results were Shards research. glass were Contrary to was thought, M Capellas research.ate in from the Egyptian Antiquities Department of the Louvre Museum. samples. the researchers Egyptian rchers demonstrated that Egyptian (inventory number E2341). These objects come and AF13175). c) Blue and turquoise necklace the vitreous matrix. This outcome made right): micro also synthetic compounds. These findingskers were fluorescence (µ-XRF)researchers demonstratedFigure 2Egyptian µ-XRF andto the that Egyptian (bottom Egyptian samples. M Capellas ombined able to synthesise exof a polishedwant “ Until now, (sample c). blue 2try green X-ray with the microstructure analysis situ fragment ofinvestigate further and to Egyptian glass provide further evidence for the sophisticated glassmakers were able to synthesisethe situ ex is 72 “ Until now, Egyptian blue and green Reference s1a) the pixel size is 0.5 × 0.5 µm2 and the probe size is 1.1 × 0.3 µm2.(blue). The map sizeonly×high-temperature edge elemental maps of antimony (red), calcium1c) and the crystalline phases reproduce were pigments antimonate compounds, which do (green) and silicon the conditions of36 µm ,preparation the chemistry and remarkable know-how of this sed calcium-antimonate compounds, whichto have been synthesised the only high-temperature PhysicsReference in nature, and added them into the compounds know n do pigments were S Lahlil et al. 2010 Applied A: Materials n, is one of the key parameters of calcium-antimonate crystals. The civilisation. We believe that this work is the ID21 ESRFopacify it. The results also show nature, and ancient them opacifiers were show that these opacifiers not exist in that indicator of calcium-antimonate glass into the Si in added Egypt. Our results researchers as anare nanocrystals. the Sb compounds were fired bet ween 700 and 10 µm compounds known to have Processing 98 1. reassessment et al. 201 Science & been synthesised starting point for a complete S Lahlil GEARS C2RM F This outcome made the researchers also synthetic compounds. These findings ure want employed. The °C for 1–18 show sophisticated in on the Egypt. Our results show Egyptian glass studies & Proces glass to opacify it. 1100resultsevidencehours,that n process to investigate further and try to provide further also for the depending ancient not only of ancient that Science
  • er laser pulse irradiates the surface of the Focus on: industry and academia Aumentando
a
Resistencia
a
Fadiga
 0 0asing the fatigue erial, producing plasma that generates ck waves. These induce compressive stress (MPa) stress (MPa) –200 –200 sses on and beneath the surface. This hod has the advantage that it improves de
um
Rolls‐Royce
e
de
um
Boeingtance of fan blades –400 –400 depth of compressive residual stress fields x x to several millimetres) in the material while –600 y –600 y ntaining a smooth surface finish. z z round 10 years ago Rolls-Royce was one –800 –800d the companies to use LSP commercially,he first © ROLLS-ROYCE PLC 2010 ying it to aero-engine fan blades. “It is 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 hestercritical that fan blades resist theolutely depth (mm) depth (mm)mprove and fretting fatigue over ct of fatigue Figure shows the in-plane (x and y) and out of plane (z) stresses with depth from the surface in the ceny thousands of flying hours,” explains root of the fan blade a) as-laser peened and b) after in-service conditions. Fretting has reduced Withers, professor of materials science the near surface compression somewhat but a significant compressive stress is maintained.n thehe University of Manchester and leader . The ESRFhe collaboration with Rolls-Royce and the with a very high spatial resolution on other applications: so far, the team has tested F. “The University of Manchester supports beamlines like ID11, ID15 and ID31 where titanium alloys (normally used in fan bladesportantin qualifying the LSP production s-Royce they carry out diffraction experiments using and biomaterials too), but also stainless steel h.cess,” he says. the poly-crystal structure as an atomic strain for applications in power plants. “In the ab X-rays require metal removal and gauge. “ID31 is especially convenient to case of aero engines, they are increasingly of fatigue surement correction to determine stress e introduction investigate the material close to the surface,” operating at higher temperatures and there isfiles and are therefore destructive. The s. The most says Withers, “but then on ID11 and ID15 you a continuous drive to make aircraft lighter. Wehly “shot ” at re penetrating, non-invasive, hard X-ray have higher energies and we can study larger need to find ways to make the materials and ich generates ms100– ESRF come into the picture ut of the components.” Neutrons are a complementary The unique titanium wide chord fan blades, seen here on a Trent 900. develop manufacturing processes that are up n the researchers try to understand the ver, Rolls- tool in this research: they allow full-size to the task and the ESRF helps us ensure that (a) ctural changes taking place in the fan ethod called (b) engine assemblies due to their even higher the science keeps up with technology,” says SP, a high- 200 200 es during the service throughout their penetrating power, although they provide less Withers. e surface of the at Rolls-Royce has techniques that can . generates 0 spatial resolution. In addition to the ESRF, the 0 M Capellasulate a very wide range of extreme service mpressive team also uses the Institut Laue-Langevin in stress (MPa) stress (MPa) –200 –200 rface. This ditions. “Synchrotron radiation is the only Grenoble as well as the ISIS neutron source, References t it improves ns stress fields ual of characterising the way that these –400 and most recently Diamond (UK). –400 A King et al.2006 Mat. Sci. & Eng. 435–6 x x ective stresses evolve over the life of the e material while –600 y The benefits of this research go from –600 y 12–18. finish. ponent without destroying the part,” underpinning the safety of the blades z z and A King et al. 2005 Materials Science Forum oyce was one –800 hers explains. SP commercially, their resistance to fretting fatigue and foreign –800 (ICRS7) 490–491 340–345. blades. “It is scientists probe the samples 5.0 6.0 7.0 damage to extending4.0 5.0 6.0 7.0 t the ESRF, 0.0 1.0 2.0 3.0 4.0 object 0.0 1.0 2.0 3.0 the method to M Turski et al. 2010 Appl. Phys. A 99 549–556. es resist the depth (mm) depth (mm) atigue over Figure shows the in-plane (x and y) and out of plane (z) stresses with depth from the surface in the s,” explains ESRFnews the fan blade a) as-laser peened and b) after in-service conditions. Fretting has reduced mb er 2010 root of
  • up Unificando
Semicondutores
para
 communication speed up communication iconductors play an extremely important role in communications technology. collected moving from the MQW laser (SAG region) to the EAM (FIELD region) that allowed to obtain the fundamental structural parameters of the system. In a technology-led world, optical-fibre communications allow, for example, people to be connected through the internet iconductor alloys lying on substrates. acelerar
a
comunicacaoorld, optical-fibre communications allow, for example, people to beoelectronic devices consist of different or cable-television signals.are normally connected (EA M) devices, w hich Multi-quantum well (MQW)grow th plane) of both well and barrier externally to the M Q W laser. EA Ms are also electroabsorption-modulated lasers (EMLs) are semiconductors heterostructures used with by fitting the observed patterne internet or cable-television signals. Multi-quantum well (MQW) ng the grow th of the M Q W laser-active M Q W heterostructures with an energy gap this aim. An Italian team has managedthatcharacterise it for at high frequencythe ESRF on a model based on the dynamic theory to can be modulated the first time at the parts of the heterostructure. The result is achievedon, different layers of semiconductors usingdulated lasers (EMLs) are semiconductors heterostructures used withsequentially deposited on the substrate, applying an external potential (Stark effect). of X-ray diffraction. Finally, the combination ISTO CKPH OTO/ VL A DIMIR YUDINrnating well and barrier regions. In well In such a way the EA M can switch from of synchrotron µ-XRD with laboratory µ-PL SAG m has managed to characterise it for the first time at the ESRF onons, electrons and holes recombine tovide the laser light, while barrier regions opaque to transparent for the light emitted by the M Q W laser. interface allowed the team to obtain the space-resolved field chemical composition from the mportant for the electrons and holes Scientists are trying to integrate both 10 7 space-resolved lattice parameter. ISTO CKPH OTO/ VL A DIMIR YUDINfinement in the wells. The parameters that M Q W laser and EA M, occupying a small area This unprecedented characterisation gave intensity (c.p.s.)able to modulate the laser wavelength 2 (typically 30 × 700 µm , so that6 in a single 10 SAG the team the opportunity to determine theded to match the minimum adsorption of 2 inch InP substrate about 2 × 10 4 devices may interface structure of the grown heterostructure with a 60optical fibres are the chemical composition be potentially processed). The optimisation 105 40 field (3 Å) along the grow th monolayer resolution ) µm 20 the width of both well and barrier regions. of these EML devices has, until now, been axis and with a micrometre resolution in the d( –4000 –2000 0 2000 0or low-speed communications, the carried out by empirical approaches because 4000grow th plane (i.e. to find out what has been ! (arcsec)uence of “ 0 ” and “1” containing of the impossibility to carry out a micron- 10 7 empirically grown). This study, requiring a Selection of some of the 35 full XRD patterns nformation is produced by directly resolved XRD study with laboratory sources. MQW laser (SAG of hard X-rays combined with a high flux intensity (c.p.s.) collected moving from thedulating the M Q W laser emission by A team from the University of Turin (Italy), micrometre resolution can be achieved in region) to the EAM (FIELD region) that allowed to obtain the fundamental structuralriable current. Such devices important role in communications technology. Semiconductors play an extremely can be Avago Technologies and the ESRF has, for the very few beamlines worldwide, such as ID22. 106 parameters of the system. characterised using laboratory X-ray first time, managed to directly measure the “These results show us the way to improve the O ptoelectronic devices consist of different (EA M) devices, w hich are normally connected the grow th plane) of both well and barrier action (XRD) and photoluminescenceexternally to the M Q W laser. these semiconductors heterostructure. The result is th process, which was previously based semiconductor alloys lying on substrates. (PL) structure of EA Ms are also parts of the thanks to grow 60 niques. Forgrow th of the M Q W laser-active During the high-speed communications, heterostructures with an energy gapbeam of ID22. MQW the micrometre X-ray achieved by fitting the observed pattern on a trial/error approach,” explains Carlo only 40 that can be modulated at high frequency using a 5 10 EML ce instabilities depositedsemiconductors region, different layers of The scientists investigatedX-raymodel basedFinally, the combination leader of the team and professor at thediffraction. on the dynamic theory ) prevent thissubstrate, simple Lamberti, µm are sequentially on the applying an external potential (Stark effect). of 20 tionalternating well andW lasers are fed and the M Q barrier regions. In well In such a way the EA M by µ-XRD and µ-X-ray fluorescence laboratory µ-PL devices can switch from the University of Turin. d( of synchrotron µ-XRD with 0 constantthe laser light, holesgenerates a regions, electrons and provide current that recombine to while barrier regions at 35 different spatial points–4000 team to obtain the space-resolved 4000 opaque to transparent for the light emitted by the M Q W laser. allowed the –2000 0 withcomposition from the M2000 chemical a spatial Capellasstant emission, w hich is not holes are important for the electrons and carrying Scientistsresolution of 2 µm, moving from the M Q W! (arcsec) are trying to integrate both space-resolved lattice parameter. information. in thecreate the information,Q W laser laser to2occupyingMsmall area With such data, characterisation gave confinement To wells. The parameters that M and EA M, the EA a region. This unprecedented References are able to modulate the laser wavelength (typically 30 × 700 µm , so that in a single the team the opportunity to determine the s containing M Q W lasersadsorption ofbe 2 inch InP substrate about 2 × to4 obtain theSelection of some of the 35 fullal. 2010 J. Anal. At. Spectrom. 25 needed to match the minimum need to it is possible 10 devices may fundamental heterostructure with aet XRD patterns structure of the grown L Minodulated externally. This modulation the optical fibres are the chemical composition is be potentially processed). The optimisation (width along the structural parameters 831–836. monolayer resolution (3 Å) along the grow th collectedamoving from the MQW laser (SAG and the width of both well and barrier regions. of these EML devices has, until now, been axis and with micrometre resolution in the with electroabsorption-modulator out by empiricaldirection because region) to(i.e. to find out whatL Mino et al. 2010 Adv. Mater. 22 2050–2054. eved For low-speed communications, the carried grow th approaches and lattice parameter on grow th plane the EAM (FIELD region) that has been sequence of “ 0 ” and “1” containing of the impossibility to carry out a micron- empirically grown). This study, requiring a the information is produced by directly resolved XRD study with laboratory sources. allowed hard obtain the fundamental structural high flux of to X-rays combined with amb ermodulating the M Q W laser emission by 2010 ESRFnews A team from the University of Turin (Italy), micrometre resolution can be achieved in
  • ces energy in this process. The ESRF has given scientists new insights into PGK.metabolic pathway that Revelando
como
o
humano
 ose into t wo molecules of Bowler, scientist at the ESRF who studies PGK. PGK harvests the energy produced in the moment that ATP is formed. They looked at the chemistry of the phosphate “energy concomitant production ofmpound, called adenosineP). The process requires armazena
energia glycolysis by transferring a phosphate “energy unit ” from one half of a glucose molecule and adds it to adenosine diphosphate (A DP unit ” as it moves from one molecule to the other. Combining the techniques of fluorine nuclear magnetic resonance with X-ray probably one of the most – ATP with one missing phosphate) to form Focus on: nature and energy crystallography has revealed in unprecedent because it evolved before ATP. Bowler teamed up with the University of detail the chemistry of the reaction (M J Cliff M BO WLER of oxygen in the Earth’s Sheffield (UK), the Institute of Enzymology et al. 2010).cose is an important fuel (Hungary) and the University of Manchester They also recently studied the large domaiand in mammals is the only (UK) to unveil the structure of PGK. movements needed by PGK to bind and relea used by the brain under PGK is formed from t wo lobes that bind molecules using the new ID14-3 beamline at s. It is also the only fuel that the molecules separately. The protein then the ESRF. By combining small angle scattering n use. swings bet ween fully open and a half-open and macromolecular crystallography, a fullonsists of 10 separate conformation that binds the molecules. picture of both the domain movements inmprise three main stages. The protein closes completely around the physiological solutions and atomic details of ps glucose in a form that molecules. One of the major problems is the molecules needed to generate energy d can be broken apart. The that phosphate groups are highly negatively has been dev eloped. The results are currently e cleavage of the six carbon charged and therefore repel each other being submitted for publication. bon units. In the third stage, when they get too close. PGK neutralises the “It is important to know how proteins d by the production of negative charges of both A DP and phosphate catalyse this reaction because it is sohat is the universal “energy allowing them to get close enough to react. It fundamental and universal, and nobody real that can be used The firstto do work (shown as a cartoon coloured as rainbow) knows what sort of transition states take pla energy-generating step in glycolysis. PGKphosphate off the threeacarbon lies open ready to receive the breakdown product then pulls the Armazenamento
Glucose
(1)
+
Clivagem
C
(2)
+
producao
ATP
(3) of glucose 1,3BPG and ADP (left). Once bound, the enzyme swings together (a 40º rotation) closing around the molecules and forcing them together (right). When together, the and creates ATP. W hen it opens again ATP – the universal energy currencyexplains Bowler. ntraction. Phosphoglycerate unit phosphate “energy unit” is transferred to ADP to make when it happens,” in all forms of life. yses the seventh step of the there is a new three carbon unit that goes M Capellas 10
reacoes Unravelling the way human guably the most important into the next step of the pathway and ATP is rst reaction that produces, released to be used by the body. Reference es, energy. “It is quite a long The team just published the structure of the M J Cliff et al. 2010 J. Am. Chem. Soc. 132 process,” explains Matthew protein in its fully closed conformation just at 6507–6516.
  • ergy the end of A pril when the greyness of At sts disclose some the winter was fading away and longer and Plants go through different steps in photosynthesis that are fuelled by water and light. sunnier days gradually began, a greener Os
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fotosintese landscape spread through France. At the same Because our structural results provide new questions about its function and organisation moment, a timely paper from a team of the insight into how the charge separation (A A munts et al. 2010).s of photosynthesis University of Gothenburg (Sweden) and the ESRF shed new light on how photosynthetic reactions of photosynthesis are stabilised by protein structural changes, some key ideas Complementary techniques bacteria are responsible for the transformation could help guide the design of future synthetic Different X-ray techniques from X-ray of light into chemical energy, a mechanism systems for artificial photosynthesis.” crystallography can also be used to study ISTO CKPH OTO.CO M that is also shared by plants. photosynthesis. The focus of the study was a photosynthetic Photosystems I and II Five years ago, Michael Haumann and reaction centre where the primary energy In plants, Photosystems I and II govern the Holger Dau, from the Freie Universität conversion reactions of photosynthesis first steps in the photosynthesis process (but, Berlin, used X-ray fluorescence on ID26 to take place, and is therefore central to the curiously, they were the last to be discovered). investigate the kinetics of the photosynthesis conversion of light to chemical energy during The way that photosynthesis works in plants process in Photosystem II. They confirmed photosynthesis. Although this membrane is that Photosystem II harnesses light energy the existence of a fifth step in the catalysis protein complex was isolated from a to split t wo water molecules (H 2 O) into O 2 , process of water into oxygen (Haumann et photosynthetic bacteria called Blastochloris protons and electrons. It drives one of the al. 2005). This step is particularly importantof viridis, it is closely related to Photosystems I most oxidising reactions known to occur in because it is directly involved in the formationof and II, which perform the same task in plants. nature and is responsible for the production of molecular oxygen. In 2008, they used X-ray Scientists wanted to study the structural of atmospheric oxygen. Photosystem I also absorption near-edge spectroscopy to study changes that happened within the protein captures sunlight and takes the electrons the photosynthesis cycle with an additional only milliseconds after inducing them with released by Photosystem II through an intermediate and proposed a new reaction light. In order to follow the structural changes antenna system, consisting of a pigment mechanism on a molecular basis for the caused by light-induced electron movements, Bacteria
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 in it is used in the transmembrane electron Plants go through different steps in photosynthesis that are fuelled by water and light. product of the water oxidation chemistry r crystallography at ID9B. Their results showed transfer reaction. Photosystem II (M Haumann et al. 2008). he same the membrane protein is able to stabilise that Because our structural results provide new questions about its function and organisation University (Israel)
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O2 M f the insight into how the charge separation (A A munts et al. 2010). d the the light-induced electron movements using reactions of photosynthesis are stabilised by used the structural biology beamlines at the heticsubtle structural changes within the protein protein structural changes, some key ideas ESRF and Swiss Light Source to uncover the Complementary techniques References rmation could help guide the design of future synthetic fraction X-ray techniques from X-ray involving atomic movements of only a Different most complete plant Photosystem I structure A Amunts et al. 2010 J Biol Chem. 285(5)nism systems for artificial photosynthesis.” crystallography can also be used to study of a nanometre (A B Wöhri et al. 2010). photosynthesis. obtained so far, revealing the locations of and 3478–86. ynthetic Richard Neutze, leader of the team, Photosystems I and II Five years ago, Michael Haumann and 17 protein subunits and interactions among M Haumann et al. 2005 Science 310 rgy In plants, Photosystems I and II govern the Holger Dau, from the Freie Universität s explainssteps in “this is the first time (but, the first that the photosynthesis process that Berlin, used X-ray fluorescence on ID26 tobound photochemical 193 non-covalently 1019–1021. he method of time-resolvedto be discovered). curiously, they were the last Laue diffraction has cofactors. The new structure allowed the investigate the kinetics of the photosynthesis M Haumann et al. 2008 PN AS 105 17384. during The way that photosynthesis works in plants been successfully used to observe structural process in Photosystem II. Theystudy the contacts among scientists to confirmed A B Wöhri et al. 2010 Science 328(5978) ane is that Photosystem II harnesses light energy the existence of a fifth step in the catalysis changes within a membrane protein complex. of water into oxygen (Haumann et to split t wo water molecules (H 2 O) into O 2 , process protein subunits, w hich can elucidate 630–633. hloris protons and electrons. It drives one of the al. 2005). This step is particularly important ms I most oxidising reactions known to occur in because it is directly involved in the formation
  • Shedding light on the past A selection of the ESRF’s fossil and cultural hits TODAYMicro X-ray beams reveal subtle chemical processes that cause 1887yellow pigment to turn brown (2011 Anal. Chem. 83 1214) 1884 1545Pigment analysis of lost portrait beneath Van Gogh’s Patch of Grass 1450(2008 Anal. Chem. 80 6436)Accumulation of sulphur compounds oxidising to sulphuric acid inwood from the Mary Rose (2005 Proc. Natl. Acad. Sci. 102 14165) 800X-ray fluorescence reveals traces of mercury in the hair of Agnes 750Sorel, famous mistress of King Charles VII of France (2005) 500Micro-diffraction shows degradation of Chinese silk fibres is due toloss of protein chains (2006 Biomacromolecules 7 777)Infrared spectroscopy reveals use of oil in paintings found in 0Bamiyan caves in Afghanistan (2008 J. Anal. At. Spectrom. 23 820) 150 BCDiffraction reveals secrets of longevity of Maya blue pigment(2006 Journals of Materials Science 44 5524)Sulphur and chlorine analysis from Pompeii frescos explains why redpigment turns to black (2006 Anal. Chem. 78 7484)Studies of fibres and pigments in Dead Sea Scrolls helps datesacred texts (2010) 1500 BCXANES studies of Egyptian glass reveal secrets of opacification(2009 Appl. Phys. A 98 1)Egyptian make-up reveals wet chemistry has been practised for thousands 2000 BC 15of years (2001 Nucl. Instrum. Methods Phys. Res., Sect. B 181 744)
  • MILLION YEARS AGO 0.1 m Microtomography shows Neanderthal teeth grew faster than human 1.9 m ones (2010 Proc. Natl. Acad. Sci. 107 20923) 7m 3D imaging of rare hominid fossil Australopithecus sediba reveals new human ancestor (2011) 12 m Complete imaging of our earliest pre-human ancestor – the Toumaï skull – the first synchrotron image of whole fossil hominid skull (2006) 65 m First published picture of a fossil using synchrotron microtomography: lower molar of a close relative to orangutan (2003 Nature 422 61) Microtomography resolves jaws of last ammonites, bringing clues about their extinction (2011 Science 331 7) Laminography of snake with legs offers clues as to whether snakes evolved 95 m from land or sea creatures (2011 J. Vert. Paleontol. 31 1) 100 m 3D structure of 356 animal inclusions revealed in 2 kg of opaque amber (2008 Microsc. Microanal. 14 251) Holotomography reveals oldest evidence of reproduction using sperm in microscopic bivalve crustaceans (2009 Science 324 1535) 300 m Oldest and only fossil brain revealed in an ancient shark-like creature by holotomography (2009 Proc. Natl. Acad. Sci. 106 5224) 400 m Internal structures of fossil algae revealed with 3D phase-contrast microtomography (2005 Am. J. Bot. 92 1152) 590 m Sub-micron images of microfossils at early developmental stages show complex embryonic development (2006 Science 312 1644) 16
  • Van
Gogh,
1888