Extraordinary High Temperature Research Articles

AmiP from hyperthermophilic Thermus parvatiensis prophage is a thermoactive and ultrathermostable peptidoglycan lytic amidase.

Bacteriophages encode a wide variety of cell wall disrupting enzymes that aid the viral escape in the final stages of infection. These lytic enzymes have accumulated notable interest due to their potential as novel antibacterials for infection treatment caused by multiple-drug resistant bacteria. Here, the detailed functional and structural characterization of Thermus parvatiensis prophage peptidoglycan lytic amidase AmiP, a globular Amidase_3 type lytic enzyme adapted to high temperatures is presented. The sequence and structure comparison with homologous lytic amidases reveals the key adaptation traits that ensure the activity and stability of AmiP at high temperatures. The crystal structure determined at a resolution of 1.8Å displays a compact α/β-fold with multiple secondary structure elements omitted or shortened compared with protein structures of similar proteins. The functional characterization of AmiP demonstrates high efficiency of catalytic activity and broad substrate specificity toward thermophilic and mesophilic bacteria strains containing Orn-type or DAP-type peptidoglycan. The here presented AmiP constitutes the most thermoactive and ultrathermostable Amidase_3 type lytic enzyme biochemically characterized with a temperature optimum at 85°C. The extraordinary high melting temperature Tm 102.6°C confirms fold stability up to approximately 100°C. Furthermore, AmiP is shown to be more active over the alkaline pH range with pH optimum at pH8.5 and tolerates NaCl up to 300 mM with the activity optimum at 25 mM NaCl. This set of beneficial characteristics suggests that AmiP can be further exploited in biotechnology.

Direct sound printing

Photo- and thermo-activated reactions are dominant in Additive Manufacturing (AM) processes for polymerization or melting/deposition of polymers. However, ultrasound activated sonochemical reactions present a unique way to generate hotspots in cavitation bubbles with extraordinary high temperature and pressure along with high heating and cooling rates which are out of reach for the current AM technologies. Here, we demonstrate 3D printing of structures using acoustic cavitation produced directly by focused ultrasound which creates sonochemical reactions in highly localized cavitation regions. Complex geometries with zero to varying porosities and 280 μm feature size are printed by our method, Direct Sound Printing (DSP), in a heat curing thermoset, Poly(dimethylsiloxane) that cannot be printed directly so far by any method. Sonochemiluminescnce, high speed imaging and process characterization experiments of DSP and potential applications such as remote distance printing are presented. Our method establishes an alternative route in AM using ultrasound as the energy source.

Impact of Si on the high-temperature oxidation of AlCr(Si)N coatings

• AlCr(Si)N coatings with an Al/Cr ratio of 70/30 and 0, 2.5 and 5 at.% Si were deposited • The oxidation behaviour up to 1460 °C was studied • Coatings were analysed by advanced cross-sectional X-ray nanodiffraction • The onset of oxidation was increased by the addition of Si from 1100 °C to 1260 °C • Complex elemental and micro-structural variations after oxidation were characterized The resistance of wear protective coatings against oxidation is crucial for their use at high temperatures. Here, three nanocomposite AlCr(Si)N coatings with a fixed Al/Cr atomic ratio of 70/30 and a varying Si-content of 0 at.%, 2.5 at.% and 5 at.% were analyzed by differential scanning calorimetry, thermogravimetric analysis and X-ray in order to understand the oxidation behavior depending on their Si-content. Additionally, a partially oxidized AlCrSiN coating with 5 at.% Si on a sapphire substrate was studied across the coating thickness by depth-resolved cross-sectional X-ray nanodiffraction and scanning trans-mission electron microscopy to investigate the elemental composition, morphology, phases and residual stress evolution of the oxide scale and the non-oxidized coating underneath. The results reveal enhanced oxidation properties of the AlCr(Si)N coatings with increasing Si-content, as demonstrated by a retarded onset of oxidation to higher temperatures from 1100 °C for AlCrN to 1260 °C for the Si-containing coatings and a simultaneous deceleration of the oxidation process. After annealing of the AlCrSiN sample with 5 at.% Si at an extraordinary high temperature of 1400 °C for 60 min in ambient air, three zones developed throughout the coating strongly differing in their composition and structure: (i) a dense oxide layer comprising an Al-rich and a Cr-rich zone formed at the very top, followed by (ii) a fine-grained transition zone with incomplete oxidation and (iii) a non-oxidized zone with a porous structure. The varying elemental composition of these zones is furthermore accompanied by micro-structural variations and a complex residual stress development revealed by cross-sectional X-ray nanodiffraction. The results provide a deeper understanding of the oxidation behavior of AlCr(Si)N coatings depending on their Si-content and the associated elemental, microstructural and residual stress evolution during high-temperature oxidation.

Synthesis of Cr50Fe6Co7Mo14C15B6Y2 bulk metallic glass with integrated merits by high-content solvent element substitution and the structural origin

Novel Cr50Fe6Co7Mo14C15B6Y2 bulk metallic glass (BMG) with a critical diameter of about 1.5 mm was developed using high-content solvent element Cr substitution for Fe from the precursor Fe41Cr15Co7Mo14C15B6Y2 BMG. The alloy possesses integrated advantages of superior glass transition temperature of 981 K, extraordinary high onset temperature of crystallization of 1018 K, dramatical high compressive fracture strength of 4.49 GPa and Vickers microhardness of 14.01 GPa, and prominent corrosion resistance of no detectable weight loss in 1 M HCl solution. The structural origin for the decreased glass-forming ability of the present alloy in comparison with its precursor Fe41Cr15Co7Mo14C15B6Y2 BMG results from the lower fraction of icosahedral-type structures (with bond pair indexes of 1551, 1541, and 1431) along with the higher fraction of crystal-like structures (with bond pair indexes of 1421, 1422, 1441 and 1661), and the covalent-like Cr–C and Cr–B bonds are responsible for the superior glass transition temperature, the onset temperature of crystallization, fracture strength and hardness, based on the ab-initio molecular dynamics simulation for the local structures. The present BMG can be a preferable alloy for industrial applications under the harsh environment of high temperature, wear and corrosion.

Rock temperature prior to failure: Analysis of 209 rockfall events in the Mont Blanc massif (Western European Alps)

AbstractPeriglacial rock walls are affected by an increase in rockfall activity attributed to permafrost degradation. While recent laboratory tests have asserted the role of permafrost in bedrock stability, linking experimental findings to field applications is hindered by the difficulty in assessing bedrock temperature at observed rockfall locations and time. In this study, we simulated bedrock temperature for 209 rockfalls inventoried in the Mont Blanc massif between 2007 and 2015 and 209,000 random events artificially created at observed rockfall locations. Real and random events are then compared in a statistical analysis to determine their significance. Permafrost conditions (or very close to 0°C) were consistently found for all events with failure depth > 6 m, and for some events affecting depths from 4 to 6 m. Shallower events were probably not related to permafrost processes. Surface temperatures were significantly high up to at least 2 months prior to failure, with the highest peaks in significance 1.5–2 months and 1–5 days before rockfalls. Similarly, temperatures at scar depths were significantly high, but steadily decreasing, 1 day to 3 weeks before failure. The study confirms that warm permafrost areas (> −2°C) are particularly prone to rockfalls, and that failures are a direct response to extraordinary high bedrock temperature in both frozen and unfrozen conditions. The results are promising for the development of a rockfall susceptibility index, but uncertainty analysis encourages the use of a greater rockfall sample and a different sample of random events.

Nanoscale investigation and control of photothermal action of gold nanostructure-coated surfaces

The combination of biological variation and nanomaterial heterogeneity makes elucidating the mechanisms of interactions between cells and nanoparticles extremely complicated. Accurate nanoparticle quantification can be extremely challenging, and cellular response can change based on the location of the nanoparticle and the cell type under investigation. These complications are only amplified by the addition of external stimuli. These limitations have yielded a wide range of studies that show effects, but often provide little mechanistic insight. Gold (Au) nanomaterials were stably immobilized onto glass coverslips treated with mercaptosilane to control both the average number of nanoparticles that interact with cells and their spatial orientation relative to the cell membrane. Surfaces were characterized optically and by electron microscopy to confirm their surface density and uniformity. The thermal response of Au nanocage-coated surfaces to near infrared laser irradiation was measured in cell culture medium and modeled computationally. The modeling showed a vastly higher thermal dose than would be predicted by bulk temperature measurements. Adherent or non-adherent cell lines were cultured directly on the nanocage-coated surface or in the medium, respectively, in culture wells and laser irradiation was applied. Survival of cells growing in suspension correlated with the bulk temperature increase in the culture medium, as measured by viability assay. Conversely, adherent cells exhibited a much greater susceptibility than expected from the bulk temperature measurement, which is ostensibly related to the close interaction with the nanoparticles on their growth substrate and induction of substantially greater thermal dose upon laser exposure. This platform is designed to be a new tool to determine how many particles need to be in contact with a cell to induce desired physical or biological effects. Here we demonstrate the delivery of precise thermal doses following laser irradiation. The anticipated biological effects based on bulk measurements vastly underestimated the effects that were observed, which is ascribed to the proximity of the nanoparticle to the cell and the extraordinary high surface temperature of the particle. This platform could be expanded to a variety of nanoparticles, external stimuli, and cell types to enable more deliberate and optimized application of nanomedicine.

An Experimental and Modeling Investigation of Tensile Creep Resistance in a Stable Nanocrystalline Alloy

Nanocrystalline materials possess excellent room temperature properties, such as high strength, wear resistance, and toughness as compared to their coarse-grained counterparts. However, due to excess free energy, nanocrystalline microstructures are unstable at higher temperatures. Significant grain growth is observed already at moderately low temperatures, limiting their broader applicability. Here, we present a design approach that leads to a significant improvement in the high temperature tensile creep resistance (up to 0.64 of the melting temperature Tm) of a nanocrystalline Cu-Ta alloy. The design approach involves alloying of pure elements for engineering nanometer sized solute clusters within the solvent grains as well as along the grain boundaries. Using a chemically optimized nanocrystalline Cu-3at.%Ta alloy as a model material system, we demonstrate that the addition of Ta nanoclusters inhibits the migration of the planar defects at higher temperatures and reduces the dislocation motion, leading to extraordinary high temperature properties. For instance, the NC Cu-3Ta alloy tested under tensile creep conditions up to the temperature of 873 K (0.64Tm) displays highly unusual behavior, including the absence of any appreciable steady-state creep deformation which is normally observed in almost all materials. This approach can be readily scaled-up for bulk manufacturing of creep resistant nanocrystalline parts. Moreover, this design strategy can be transferred to other multicomponent systems such as Ni-based alloys for making nanocrystalline materials with tailored properties.

West Nile Virus Epidemic in Germany Triggered by Epizootic Emergence, 2019.

One year after the first autochthonous transmission of West Nile virus (WNV) to birds and horses in Germany, an epizootic emergence of WNV was again observed in 2019. The number of infected birds and horses was considerably higher compared to 2018 (12 birds, two horses), resulting in the observation of the first WNV epidemy in Germany: 76 cases in birds, 36 in horses and five confirmed mosquito-borne, autochthonous human cases. We demonstrated that Germany experienced several WNV introduction events and that strains of a distinct group (Eastern German WNV clade), which was introduced to Germany as a single introduction event, dominated mosquito, birds, horse and human-related virus variants in 2018 and 2019. Virus strains in this clade are characterized by a specific-Lys2114Arg mutation, which might lead to an increase in viral fitness. Extraordinary high temperatures in 2018/2019 allowed a low extrinsic incubation period (EIP), which drove the epizootic emergence and, in the end, most likely triggered the 2019 epidemic. Spatiotemporal EIP values correlated with the geographical WNV incidence. This study highlights the risk of a further spread in Germany in the next years with additional human WNV infections. Thus, surveillance of birds is essential to provide an early epidemic warning and thus, initiate targeted control measures.

Custom-Made Reinforcement Structures Made of Inorganic Fibers Challenges, Chances and Technical Approaches

Ceramic fibers are just as glass and basalt member of the group of inorganic fibers. Like most types of inorganic fibers ceramic fibers have a high tear resistance but a limited flexibility. [1] Ceramic fibers are characterized by their extraordinary high temperature and chemical resistance. These properties make them interesting for different high technical applications, as they occur in aerospace, chemical-and energy technology. In this field, they are applied especially as a reinforcement component in composite materials. Not only the partially high material price, but although the typical brittleness of ceramic fibers bring huge problems during the textile production chain, which limits the availability of complex textile preforms in the market. Often, a radical revision of the machine and processing concept is necessary to enable an economical production process. The Application Center for Textile Fiber Ceramics TFK at Fraunhofer-Center for High Temperature Materials and Design HTL develops and modifies textile production processes to make them suitable for the special requirements of ceramic fibers. One and multilayer woven fabrics, braids and tape structures for the winding process have already been successfully implemented. A further development complex is the intensive investigation of three-dimensional textile reinforcement structures. Regarding the high material costs, these research activities are very important. If the textile reinforcement is placed only where needed, the amount of used fiber material can be reduced significantly.

West Nile virus epizootic in Germany, 2018

The summer of 2018 in Germany was the second hottest and driest on record. These generally extremely favorable climatic conditions most likely triggered the further expansion and the efficient propagation of the zoonotic arthropod-borne West Nile virus in many Southern/Southeastern and even Central European countries. WNV infections were detected for the first time in resident wild and aviary birds, such as common blackbirds, northern goshawks and great grey owls in Eastern and Southeastern Germany. The causative WNV strain belonged to the central European subclade II. Phylogeographic analysis indicated a single introduction event of WNV into Germany, most likely in 2016 from Czech Republic, and also a unique non-synonymous mutation in the NS3 gene. Extraordinary high temperatures in 2018 presumably led to decreased averaged extrinsic incubation period values for WNV in mosquitoes, leading to rapid virus amplification and greater transmission risk for vertebrates in Germany. Blood transfusion services and clinicians in Germany should be aware of these possible WNV infection risks in humans especially during late summer.

Vitality loss of European beech (Fagus sylvatica L.) and infestation by the European beech splendour beetle (Agrilus viridis L., Buprestidae, Coleoptera)

Despite its dominance in Central Europe, beech cultivation is not without risks, because drought periods and direct solar radiation of the stem are suspected of causing branch dieback, sunburn and predisposition to attack by the European beech splendour beetle Agrilus viridis. Outbreaks of this beetle occurred in Germany in the early 1950s and in Hungary between 2003 and 2006 following severe precipitation deficiencies and extraordinary high temperatures. Leaf loss and an unusual accumulation of dead branches at the top of the crown of beech trees prompted us to initiate in 2010 a three-year study to investigate whether and to what extent A. viridis infestations are involved in this damage pattern. In eight differently damaged beech stands in Bavaria (south-eastern Germany) we measured the prevalence of A. viridis with flight interception traps in relation to the vitality status of beech, checked the oviposition behaviour of females on trap trees, and investigated the infestation frequency of beech trees depending on stand structure. The prevalence of A. viridis was significantly enhanced in sample plots with more heavily damaged beech trees. At lying trap trees, females preferred parts of the bark for oviposition which had been exposed to south or west when the trees had been standing. Particularly, trees in open stands, distant to neighbours in the south and west as well as damaged by sunburn are predisposed to attack by A. viridis. It was proved that survival of A. viridis occurred in branches at the top of live beech trees from where outbreak situations may be initiated due to climatic conditions like drought and/or extreme temperatures. Prevention of A. viridis infestation consists of avoiding sudden exposure to intense solar radiation of the beech trunk by silvicultural measures.

Ultrasonic polymerization of CuO@PNIPAM and its temperature tuning glucose sensing behavior

The extraordinary high pressure and temperature produced during cavitation is crucial for ultrasonic sonochemistry. However, the cavitation effect is usually confined to a small zone nearby the ultrasonic horn, outside of which ultrasound produces much less effects on chemical reaction. In present work, in order to expand the range of effective zone and intensify the cavitation effect, N2 aeration was introduced to an ultrasonic polymerization process of CuO@PNIPAM in aqueous solution. By increasing the number of bubble nucleus gathered on the CuO surface and lowering the surface tension of the aqueous solution, the cavitation effect is intensified on the CuO surface within the whole reaction vessel, which benefits the covalently bonding between PNIPAM and CuO to a large degree and results in the formation of CuO@PNIPAM hybrid composite with excellent interfacial bonding. It is promising that the hybrid composite can be applied as temperature responsive glucose sensing platform with ON and OFF states due to the wettability change of PNIPAM versus temperature.

The extreme European summer of 2015 in a long‐term perspective

ABSTRACTIn 2015, large parts of Europe were characterized by extraordinary high summer temperatures, accompanied by very dry conditions, particularly in central‐eastern Europe. Several major heat episodes occurred from the end of June until mid‐September. We provide an ad‐hoc evaluation of the observed climatological extremes in a secular context, by using a set of long station time series in daily resolution. Our data set comprises 42 temperature and 43 precipitation records, predominantly starting already in the 19th century. To investigate local record values, the individual full record length is analysed for each station, while regionally averaged analyses are presented for the core study period of 1901–2015. The study area covers Europe's central latitudes (44° to 52°N), extending from England in the west up to the central Ukraine in the east.During summer 2015, various indices representing extremely high maximum and minimum temperatures (strongly) exceeded previous record high values, mainly in an area extending from eastern Germany to western Ukraine. Additionally, severely to extremely dry conditions with unusually frequent dry days were prevailing particularly in the (central‐) eastern part of the study area. Drought indices combining temperature and precipitation revealed drought conditions comparable or even worse than those of former extreme summers like 2003.

Experimental evidence of new tetragonal polymorphs of silicon formed through ultrafast laser-induced confined microexplosion.

Ordinary materials can transform into novel phases at extraordinary high pressure and temperature. The recently developed method of ultrashort laser-induced confined microexplosions initiates a non-equilibrium disordered plasma state. Ultra-high quenching rates overcome kinetic barriers to the formation of new metastable phases, which are preserved in the surrounding pristine crystal for subsequent exploitation. Here we demonstrate that confined microexplosions in silicon produce several metastable end phases. Comparison with an ab initio random structure search reveals six energetically competitive potential phases, four tetragonal and two monoclinic structures. We show the presence of bt8 and st12, which have been predicted theoretically previously, but have not been observed in nature or in laboratory experiments. In addition, the presence of the as yet unidentified silicon phase, Si-VIII and two of our other predicted tetragonal phases are highly likely within laser-affected zones. These findings may pave the way for new materials with novel and exotic properties.

Ce:YAG transparent ceramics for applications of high power LEDs: Thickness effects and high temperature performance

Abstract Ce doped Y 3 Al 5 O 12 (Ce:YAG) transparent ceramics could be combined with blue chips of high power output, for applications of high power white light emitting diodes (LEDs). In this paper, we found that through the thickness variation of Ce:YAG transparent ceramics, emission spectrum and the color coordinates of the assembled LEDs could be adjusted from cold white to warm white light region. Ce:YAG transparent ceramics showed extraordinary high temperature quenching properties, they even kept almost 90% of initial luminescence intensity (room temperature) at temperature of 200 °C, which are superior to both the commercial yellow phosphors and white LEDs. By a far infrared temperature detecting system, the surface temperature of the assembled LEDs was recorded and compared to commercial ones, Ce:YAG transparent ceramics with higher thickness showed lower surface temperature, and Ce:YAG transparent ceramics also showed lower surface temperature than commercial white LEDs. Ce:YAG transparent ceramics combined to blue chips seems a good candidate for next generation high power light sources.

Facile Synthesis of Aliovalent Vanadium Doped High Voltage LiNi0.5Mn1.5O4 Cathode With Extraordinary High Temperature Performance

not Available.

Distribution of structural domains in MnAs layers grown on GaAs substrates

Electron backscatter diffraction is utilized to determine the distribution of coexisting structural domains in MnAs layers prepared on GaAs substrates. In a layer grown on a GaAs(111)B substrate using solid phase epitaxy, the structural domains roughly correspond to the morphological features of the surface. The domains are, in contrast, considerably larger in size than the surface roughness when the substrate is GaAs(113)A. We examine the role of the freedom in in-plane crystalline alignment for causing such a difference using a numerical model. In a layer grown at an extraordinary high temperature (600 °C) on a GaAs(111)B substrate, (0001) and (11¯0l) orientations are interwoven. While the (0001) component is present mainly as thin flat films, a mixture of all the components forms thick elongated islands in the surrounding of the films. Consequences of such an inhomogeneity on the magnetic and electrical properties of the layer are discussed.

농작물 재배와 관련된 이상기온 출현 일수의 기후학적 지역 특성

월별 <TEX>$2{\sigma}$</TEX>값 분포를 보면, 4~7월까지 4개월 동안, 전국에서 <TEX>$2{\sigma}$</TEX>값이 가장 크게 나타난 곳은 강릉이었으며, 또한, 동해안 지역이 다른 지역에 비해 상대적으로 제일 큰 값이 나타나, 기후학적으로 기온 변동폭이 큰 지역임을 뚜렷이 잘 보여주었다. 그리고 전 지역 평균한 <TEX>$2{\sigma}$</TEX>값의 월별 크기를 비교해보면, 4월의 <TEX>$2{\sigma}$</TEX>값이 5.6도로 제일 컸다. 월별 이상저온 및 이상고온 출현일수 분포에서는, 4월의 경우, 30일 이상의 이상고온 출현 일수를 기록한 지역은 대부분의 서해안 지역과 동해안 지역인 속초와 영덕, 그리고 제주이다. 특히 강화에서는 이상고온 출현 일수가 무려 45일이나 되었으며, 조사 월인 4~10월 중에서 이상고온 출현 일수가 제일 많은 월로, 그리고, 이상저온 출현 일수가 제일 적게 나타난 월이었다. 따라서 4월의 경우, 동해안 지역과 서해안 지역은 이상저온에 따른 냉해보다는 이상고온에 따른 피해 대책에 더욱 유의할 필요가 있겠다. 한편, 8월은 기후학적으로 제일 더운 계절이지만, 이상저온 출현 일수가 30일 이상이 되는 지역이 분석기간 중에서 제일 광범위하며, 또한 이상저온 출현 일수가 제일 많은 달이다, 특히, 강원도 내륙, 충청도 내륙, 그리고 남부 지방에서 최다인 반면에, 이상고온 출현 일수가 제일 적게 나타난 월이었다. 따라서 8월은 모든 월 중에서 이상고온보다는 이상저온과 관련하여 농작물 재배에 있어 제일 세심한 관리가 요구되는 월로 분석되었다. Using 61 observation data of the recent 30 years from 1979 to 2008, we have identified the areas which had climatologically frequent occurrence of extraordinary low and high temperature leading to meteorological disasters. The station of the highest temperature deviation was Gangneungduring the period of April through July. Furthermore, the eastern coast region including Gangneung recorded the largest amplitude of temperature deviation in Korea, showing the climatological evidence that the temporal variation was the largest. During the period of April to October, most of the days with extraordinary high temperature were found in April. The regionswith more than 30days of extraordinary high temperature werethe eastern and western coast regions. Thus, special attention to prevent the meteorological disaster related to extraordinary high temperature is required in the coast regions particularly during April. Meanwhile, further attention to prevent the disaster related to extraordinary low temperature is required in Gangwon inland, Chungcheong inland, and the southern province especially in August.

Off-stoichiometry in Co2FeSi thin films sputtered from stoichiometric targets revealed by nuclear magnetic resonance

Co2FeSi is predicted to be a half-metallic ferromagnet with an extraordinary high magnetic moment and Curie temperature. However, a low tunnel magneto-resistance ratio, a lower spin polarization and a lower magnetic moment were experimentally observed in thin film samples. Consequently, thin Co2FeSi films of different groups were studied using spin-echo nuclear magnetic resonance (NMR). NMR probes the local hyperfine fields of the active atoms, which strongly depend on the local environment. NMR is thus able to reveal the next neighbouring shells of the 59Co nuclei in the Co2FeSi thin films. As expected, our NMR study shows the main resonance line corresponding to 59Co nuclei in the L21 environment but also additional resonance lines at the high frequency site of the main line with a spacing between adjacent resonance lines of 32 MHz. The additional resonance lines correspond to 59Co with more Fe next neighbours than expected for the L21 type ordering, which is interpreted as the formation of an off-stoichiometric film yielded by sputtering from a stoichiometric target. The analysis of the NMR data and a comparison with off-stoichiometric bulk samples reveals the composition of the thin films to be about Co2Fe(Si0.92Fe0.08). This off-stoichiometry might explain the observed deviations from the expected behaviour.

Nanodomain growth in amorphous Si–C–N

AbstractPolymer‐derived amorphous Si–C–N ceramics are phase separated into amorphous nanodomains after thermolysis. These nanodomains are expected to have a crucial importance for the extraordinary high temperature stability of these materials. We investigated nanodomain growth during isothermal annealing at 1400 °C using small angle X‐ray scattering. The as‐thermolyzed sample shows a domain radius of about 5 Å as determined from Guinier plots. During annealing, fast nanodomain growth up to 9 Å is observed for times up to 30 h while for longer annealing times up to 165 h the growth considerably slows down, resulting in a domain size of 11 Å. The experimental data can be fitted by a model based on diffusion controlled domain growth and simultaneous slow‐down of diffusion due to structural relaxation. (© 2009 WILEY‐VCH Verlag GmbH &amp; Co. KGaA, Weinheim)