Artículos de revistas: "-µ analyse in situ"

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Sato, Motohiko, Eiichi Tani, Tsuyoshi Matsumoto, Hirokazu Fujikawa y Shinobu Imajoh-Ohmi. "Generation of the catalytic fragment of protein kinase C alpha in spastic canine basilar artery". Journal of Neurosurgery 87, n.º 5 (noviembre de 1997): 752–56. http://dx.doi.org/10.3171/jns.1997.87.5.0752.

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✓ In previous studies of topical application of calphostin C, a specific inhibitor of the regulatory domain of protein kinase C (PKC), and calpeptin, a selective inhibitor of calpain, to spastic canine basilar artery (BA) researchers have suggested that the catalytic fragment of PKC (known as PKM) is probably formed by a limited proteolysis of continuously activated µ-calpain, but there has been no direct evidence for PKM formation in vasospasm. The present immunoblot study with anti-PKCα antibody shows a significant decrease in cytosolic 80-kD PKCα and a concomitantly significant increase in membrane PKCα in the spastic canine BA. In addition, an immunoblot study in which cleavage site—directed antibodies were used demonstrated a significant increase in immunoreactive 45-kD PKM. The changes in membrane PKCα and PKM were enhanced with the lapse of time after subarachnoid hemorrhage. The cleavage site—directed antibodies distinguish the proteolyzed from the unproteolyzed forms of PKC for in situ analyses of enzyme regulation mediated by proteolysis. The data indicate that PKCα in spastic canine BA is translocated to the cell membrane, where PKCα is rapidly cleaved into PKM as a result of proteolysis of the isozyme by µ-calpain but not by µ-calpain. The authors hypothesize that µ-calpain is continuously activated in spastic canine BA and produces PKM by limited proteolysis of PKCα.

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Camin, Bettina y Lennart Hansen. "In Situ 3D-µ-Tomography on Particle-Reinforced Light Metal Matrix Composite Materials under Creep Conditions". Metals 10, n.º 8 (1 de agosto de 2020): 1034. http://dx.doi.org/10.3390/met10081034.

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In transportation light metal matrix composites (L-MMCs) are used increasingly due to their improved creep resistance even at higher application temperatures. Therefore, the creep behavior and failure mechanisms of creep loaded particle reinforced L-MMCs have been investigated intensively. Until now, creep damage analyses are usually performed ex situ by means of interrupted creep experiments. However, ex situ methods do not provide sufficient information about the evolution of creep damage. Hence, in situ synchrotron X-ray 3D-µ-tomography investigations were carried out enabling time and space resolved studies of the damage mechanisms in particle-reinforced titanium- and aluminum-based metal matrix composites (MMCs) during creep. The 3D-data were visualized and existing models were applied, specifying the phenomenology of the damage in the early and late creep stages. During the early stages of creep, the damage is determined by surface diffusion in the matrix or reinforcement fracture, both evolving proportionally to the macroscopic creep curve. In the late creep stages the damage mechanisms are quite different: In the Al-MMC, the identified mechanisms persist proportional to creep strain. In contrast, in the titanium-MMC, a changeover to the mechanism of dislocation creep evolving super-proportionally to creep strain occurs.

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Intan, T. K., D. Munir, N. N. Soeroso, M. Ichwan, H. Khair y I. Suryati. "The relevancy-analysis of air quality index to Acute Respiratory Infection (ARI) in A landfill site of Medan". IOP Conference Series: Earth and Environmental Science 1241, n.º 1 (1 de septiembre de 2023): 012117. http://dx.doi.org/10.1088/1755-1315/1241/1/012117.

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Abstract The existence of open dumping in Medan City’s final waste processing since 1993 has certainly had a negative impact in the form of a decrease in air quality which has a further impact on public health problems. This study aims to analyse and maps the distribution of PM10 and PM2.5 concentrations in the Terjun Landfill and to examine the relationship between the air quality index and the prevalence of acute respiratory infection (ARI) in the nearby landfill site. The sampling method for this research uses the manual active and is mapped using the GIS application. The results of ambient air concentrations were converted into an air quality index which subsequently was tested in a statistical correlative method to investigate the prevalence of ARI. The results demonstrated the PM2.5 concentrations ranged from 38.94 – 163.1 µ/m3, the PM10 was between 46.84 – 184.2 µ/m3; indicating an excessive level of national ambient threshold. The distribution of the highest PM2.5 and PM10 is in the active zone of the landfill. The prevalence of ARI in the nearby landfill site showed a strong relationship; 0.86 for PM2.5 and 0.62 for PM10. These findings illustrate a poor-quality air would increase the number of inhabitants with ARI.

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Gil, Milene, Mafalda Costa, Mila Cvetkovic, Carlo Bottaini, Ana Margarida Cardoso, Ana Manhita, Cristina Barrocas Dias y António Candeias. "Unveiling the mural painting art of Almada Negreiros at the Maritime Stations of Alcântara (Lisbon): diagnosis research of paint layers as a guide for its future conservation". Ge-conservacion 20 (25 de octubre de 2021): 105–17. http://dx.doi.org/10.37558/gec.v20i1.1027.

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This paper reports the diagnostic research of deteriorated paint layers from three mural panels made by Almada Negreiros found in the Alcântara Maritime Station in Lisbon. The aim was to understand the main decay phenomena to aid future conservation works. The methodology comprised in-situ analyses by technical photography in Vis, Vis-RaK and UVF, p-OM and h-EDXRF; micro sampling; OM, SEM-EDS, μ-XRD, μ-Raman, µ-FT-IR and Py-GC/MS. Preliminary results show that all the paint layers analyzed are affected by salts (alkali sulphates) that over time have caused flacking, lack of cohesion, erosion, and lacunae. The light greenish/greenish bluish paint layers in all three panels are the most affected. No organic binders were identified, only the presence of vinyl polymer in glossy paint surfaces.

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Hendl, Julius, Sina Daubner, Axel Marquardt, Lukas Stepien, Elena Lopez, Frank Brückner y Christoph Leyens. "In Situ CT Tensile Testing of an Additively Manufactured and Heat-Treated Metastable ß-Titanium Alloy (Ti-5Al-5Mo-5V-3Cr)". Applied Sciences 11, n.º 21 (22 de octubre de 2021): 9875. http://dx.doi.org/10.3390/app11219875.

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Additive manufacturing has been considered a suitable process for developing high-performance parts of medical or aerospace industries. The electron beam powder bed fusion process, EB-PBF, is a powder bed fusion process carried out in a vacuum, in which the parts are melted using a highly focused electron beam. The material class of metastable β-titanium alloys, and especially Ti-5Al-5Mo-5V-3Cr, show great potential for use as small and highly complex load-bearing parts. Specimens were additively manufactured with optimised process parameters and different heat treatments used in order to create tailored mechanical properties. These heat-treated specimens were analysed with regard to their microstructure (SEM) and their mechanical strength (tensile testing). Furthermore, in situ tensile tests, using a Deben CT5000 and a YXLON ff35 industrial µ-CT, were performed and failure-critical defects were detected, analysed and monitored. Experimental results indicate that, if EB-PBF-manufactured Ti-5553 is heat-treated differently, a variety of mechanical properties are possible. Regarding their fracture mechanisms, failure-critical defects can be detected at different stages of the tensile test and defect growth behaviour can be analysed.

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Shih, J. K. C., J. R. Omer, R. Delpak, R. B. Robinson y C. D. Jones. "Full-scale pile tests in sand and development of a computer program for predicting load capacity". Canadian Journal of Civil Engineering 34, n.º 10 (1 de octubre de 2007): 1222–36. http://dx.doi.org/10.1139/l07-047.

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An interactive computer program GLAMPILE has been developed for predicting the static load capacity of single piles formed in any soil profile. A variety of well-known prediction methods have been incorporated into the program, including (i) soil mechanics based formulae; (ii) direct and indirect cone penetration test (CPT) based methods with and without accounting for scale effects of the cone on pile base capacity; and (iii) a new CPT-based method that considers the effects of critical depth and shaft resistance distribution, although the method has only been calibrated for relatively short piles. GLAMPILE can cope with different pile types installed with or without a permanent casing. The program has been applied to predict the axial capacities of 11 piles that were recently installed in sand and statically loaded to failure. Results from the soil mechanics procedures indicate increases, on the in situ value, of the earth pressure coefficient by up to 37%, which lies within the range 0%–100% recommended in the literature. The best CPT-based prediction method applied yields a mean (µ) and coefficient of variation (COV) of predicted to measured pile head capacity (Puh(p)/Puh(m)) of 0.83 and 0.12, respectively. Scale effects are shown to be nominal for the cases analysed. An improved method is recommended, which yields µ = 1.00 and COV = 0.10, implying higher accuracy and reliability compared with the other methods.Key words: piles, cone penetration test, static and dynamic load test, modular program.

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Pinto, Simone de Souza y Mirabel Cerqueira Rezende. "Electromagnetic, Morphological, and Electrical Characterization of POMA/Carbon Nanotubes-Based Composites". Journal of Nanomaterials 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/1989785.

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This study involves the preparation of conducting composites based on poly(o-methoxyaniline) (POMA) and carbon nanotubes (CNT) and the evaluation of them as radar absorbing materials (RAM), in the frequency range of 8.2–12.4 GHz (X-band). The composites were obtained by synthesis in situ of POMA in the presence of CNT (0.1 and 0.5 wt% in relation to the o-methoxyaniline monomer). The resulting samples—POMA/CNT-0.1 wt% and POMA/CNT-0.5 wt%—were incorporated in an epoxy resin matrix in the proportion of 1 and 10 wt%. FT-IR analyses show that the POMA was successfully synthesized on the CNT surface. SEM analyses show that the synthesized POMA recovered all CNT surface. Electrical conductivity measurements show that the CNT contributed to increase the conductivity of POMA/CNT composites (1.5–6.7 S·cm−1) in relation to the neat POMA (5.4 × 10−1 S·cm−1). The electromagnetic characterization involved the measurements of complex parameters of electrical permittivity (ε) and magnetic permeability (µ), using a waveguide in the X-band. From these experimental data reflection loss (RL) simulations were performed for specimens with different thicknesses. The complex parameters show that the CNT in the composites increased ε and µ. These results are attributed to the CNT network formation into the composites. Simulated RL curves of neat POMA and POMA/CNT in epoxy resin show the preponderant influence of POMA on all RL curves. This behavior is attributed to the efficient CNT recovering by POMA. RL results show that the composite based on 10 wt% of POMA/CNT-0.5 wt% in epoxy resin (9 mm thickness) presents the best RL results (≈87% of attenuation at 12.4 GHz).

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Zwettler, Niklas, Madeleine A. Ehweiner, Jörg A. Schachner, Antoine Dupé, Ferdinand Belaj y Nadia C. Mösch-Zanetti. "Dioxygen Activation with Molybdenum Complexes Bearing Amide-Functionalized Iminophenolate Ligands". Molecules 24, n.º 9 (10 de mayo de 2019): 1814. http://dx.doi.org/10.3390/molecules24091814.

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Two novel iminophenolate ligands with amidopropyl side chains (HL2 and HL3) on the imine functionality have been synthesized in order to prepare dioxidomolybdenum(VI) complexes of the general structure [MoO2L2] featuring pendant internal hydrogen bond donors. For reasons of comparison, a previously published complex featuring n-butyl side chains (L1) was included in the investigation. Three complexes (1–3) obtained using these ligands (HL1–HL3) were able to activate dioxygen in an in situ approach: The intermediate molybdenum(IV) species [MoO(PMe3)L2] is first generated by treatment with an excess of PMe3. Subsequent reaction with dioxygen leads to oxido peroxido complexes of the structure [MoO(O2)L2]. For the complex employing the ligand with the n-butyl side chain, the isolation of the oxidomolybdenum(IV) phosphino complex [MoO(PMe3)(L1)2] (4) was successful, whereas the respective Mo(IV) species employing the ligands with the amidopropyl side chains were found to be not stable enough to be isolated. The three oxido peroxido complexes of the structure [MoO(O2)L2] (9–11) were systematically compared to assess the influence of internal hydrogen bonds on the geometry as well as the catalytic activity in aerobic oxidation. All complexes were characterized by spectroscopic means. Furthermore, molecular structures were determined by single-crystal X-ray diffraction analyses of HL3, 1–3, 9–11 together with three polynuclear products {[MoO(L2)2]2(µ-O)} (7), {[MoO(L2)]4(µ-O)6} (8) and [C9H13N2O]4[Mo8O26]·6OPMe3 (12) which were obtained during the synthesis of reduced complexes of the type [MoO(PMe3)L2] (4–6).

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Carvalho, Denise A. M., Vânia C. Pinto, Paulo J. Sousa, Vitor H. Magalhães, Emilio Fernández, Pedro A. Gomes, Graça Minas y Luís M. Gonçalves. "Methodology for Phytoplankton Taxonomic Group Identification towards the Development of a Lab-on-a-Chip". Applied Sciences 12, n.º 11 (26 de mayo de 2022): 5376. http://dx.doi.org/10.3390/app12115376.

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This paper presents the absorbance and fluorescence optical properties of various phytoplankton species, looking to achieve an accurate method to detect and identify a number of phytoplankton taxonomic groups. The methodology to select the excitation and detection wavelengths that results in superior identification of phytoplankton is reported. The macroscopic analyses and the implemented methodology are the base for designing a lab-on-a-chip device for a phytoplankton group identification, based on cell analysis with multi-wavelength lighting excitation, aiming for a cheap and portable platform. With such methodology in a lab-on-a-chip device, the analysis of the phytoplankton cells’ optical properties, e.g., fluorescence, diffraction, absorption and reflection, will be possible. This device will offer, in the future, a platform for continuous, autonomous and in situ underwater measurements, in opposition to the conventional methodology. A proof-of-concept device with LED light excitation at 450 nm and a detection photodiode at 680 nm was fabricated. This device was able to quantify the concentration of the phytoplankton chlorophyll a. A lock-in amplifier electronic circuit was developed and integrated in a portable and low-cost sensor, featuring continuous, autonomous and in situ underwater measurements. This device has a detection limit of 0.01 µ/L of chlorophyll a, in a range up to 300 µg/L, with a linear voltage output with chlorophyll concentration.

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Kille, P., A. J. Morgan, K. Powell, J. F. W. Mosselmans, D. Hart, P. Gunning, A. Hayes, D. Scarborough, I. McDonald y J. M. Charnock. "‘Venus trapped, Mars transits': Cu and Fe redox chemistry, cellular topography and in situ ligand binding in terrestrial isopod hepatopancreas". Open Biology 6, n.º 3 (marzo de 2016): 150270. http://dx.doi.org/10.1098/rsob.150270.

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Woodlice efficiently sequester copper (Cu) in ‘cuprosomes' within hepatopancreatic ‘S' cells. Binuclear ‘B’ cells in the hepatopancreas form iron (Fe) deposits; these cells apparently undergo an apocrine secretory diurnal cycle linked to nocturnal feeding. Synchrotron-based µ-focus X-ray spectroscopy undertaken on thin sections was used to characterize the ligands binding Cu and Fe in S and B cells of Oniscus asellus (Isopoda). Main findings were: (i) morphometry confirmed a diurnal B-cell apocrine cycle; (ii) X-ray fluorescence (XRF) mapping indicated that Cu was co-distributed with sulfur (mainly in S cells), and Fe was co-distributed with phosphate (mainly in B cells); (iii) XRF mapping revealed an intimate morphological relationship between the basal regions of adjacent S and B cells; (iv) molecular modelling and Fourier transform analyses indicated that Cu in the reduced Cu + state is mainly coordinated to thiol-rich ligands (Cu–S bond length 2.3 Å) in both cell types, while Fe in the oxidized Fe 3+ state is predominantly oxygen coordinated (estimated Fe–O bond length of approx. 2 Å), with an outer shell of Fe scatterers at approximately 3.05 Å; and (v) no significant differences occur in Cu or Fe speciation at key nodes in the apocrine cycle. Findings imply that S and B cells form integrated unit-pairs; a functional role for secretions from these cellular units in the digestion of recalcitrant dietary components is hypothesized.

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Singh, Amitoj, Ashwantha Kumar Enjapoori, Yann Gibert y Karen M. Dwyer. "The protective effects of human milk-derived peptides on the pancreatic islet biology". Biology Open 9, n.º 8 (21 de julio de 2020): bio049304. http://dx.doi.org/10.1242/bio.049304.

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ABSTRACTSeveral epidemiological studies support the protective role of breastfeeding in reducing the risk for type 1 diabetes. Human breast milk is the perfect nutrition for infants and contains many complex proteins, lipids and carbohydrates. In this study, we examined the physiological effects of human milk-derived opioid peptides, β-casomorphins (BCM), and compared them with bovine-milk-derived opioid peptides on pancreatic hormone regulation and β-cell regeneration. Exposure of wild-type zebrafish embryos to 50 µg/ml of human BCM-5 and -7 from 3 days post fertilisation until 6 days post fertilisation resulted in an increased insulin domain of expression while exposure to bovine BCM-5 and -7 significantly reduced the insulin domain of expression as analysed by whole-mount in situ hybridisation. These changes may be accounted for by reduced insulin expression or β-cell number and were mitigated by the µ-opioid receptor antagonist, naloxone. The effect of BCM on β-cell regeneration was assessed following ablation of β-cells in Tg (ins: CFP-NTR) zebrafish from 3 days post fertilisation to 4 days post fertilisation, followed by exposure of bovine and human BCM-5 and -7 (50 µg/ml) from 4 days post fertilisation until 7 days post fertilisation. The regenerative capacity of β-cells was not impeded following exposure to human BCM-5 and -7, whereas the capacity of β-cells to regenerate following bovine BCM-5 and -7 exposure was reduced. Our data suggest that human BCM-5 and -7 may promote β-cell development and enable the regeneration of β-cells, while the bovine-milk-derived peptides, BCM-5 and -7, play an opposite role. These data may provide some biological explanation for the protective effect of breastfeeding on the development of type 1 diabetes.

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Weber, Martin, Gábor Balázs, Alexander V. Virovets, Eugenia Peresypkina y Manfred Scheer. "Insertion of Phosphenium Ions into a Bicyclo[1.1.0]Tetraphosphabutane Iron Complex". Molecules 26, n.º 13 (26 de junio de 2021): 3920. http://dx.doi.org/10.3390/molecules26133920.

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By reacting [{Cp‴Fe(CO)2}2(µ,η1:1-P4)] (1) with in situ generated phosphenium ions [Ph2P][A] ([A]− = [OTf]− = [O3SCF3]−, [PF6]−), a mixture of two main products of the composition [{Cp‴Fe(CO)2}2(µ,η1:1-P5(C6H5)2)][PF6] (2a and 3a) could be identified by extensive 31P NMR spectroscopic studies at 193 K. Compound 3a was also characterized by X-ray diffraction analysis, showing the rarely observed bicyclo[2.1.0]pentaphosphapentane unit. At room temperature, the novel compound [{Cp‴Fe}(µ,η4:1-P5Ph2){Cp‴(CO)2Fe}][PF6] (4) is formed by decarbonylation. Reacting 1 with in situ generated diphenyl arsenium ions gives short-lived intermediates at 193 K which disproportionate at room temperature into tetraphenyldiarsine and [{Cp‴Fe(CO)2}4(µ4,η1:1:1:1-P8)][OTf]2 (5) containing a tetracyclo[3.3.0.02,7.03,6]octaphosphaoctane ligand.

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Zafar, Mohd Farhan y M. Arif Siddiqui. "Mechanical Characterization of the Natural Fiber Reinforced Polystyrene Composite". Materials Science Forum 969 (agosto de 2019): 152–56. http://dx.doi.org/10.4028/www.scientific.net/msf.969.152.

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In the present work, polystyrene composites using wheat husk, rice husk and mustard husk as fillers are synthesized using in-situ polymerisation technique. Three different filler loading (5%, 10% and 15 %) and three different filler sizes (250-355 µ, 355-500 µ, 500-710 µ) were utilized for the studying the effect of these compositions on different mechanical properties of the synthesized composites. The results have shown that the filler size 250-355 µ and 5 % loading give the maximum values for tensile strength, flexural strength and hardness for all the three types of fillers. While in case of water absorptivity lower the size/loading, lesser would be the water absorbed. The SEM analysis is done to study the fractured surface of the specimen.

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Eichler, Jan, Ina Kleitz, Maddalena Bayer-Giraldi, Daniela Jansen, Sepp Kipfstuhl, Wataru Shigeyama, Christian Weikusat y Ilka Weikusat. "Location and distribution of micro-inclusions in the EDML and NEEM ice cores using optical microscopy and in situ Raman spectroscopy". Cryosphere 11, n.º 3 (5 de mayo de 2017): 1075–90. http://dx.doi.org/10.5194/tc-11-1075-2017.

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Abstract. Impurities control a variety of physical properties of polar ice. Their impact can be observed at all scales – from the microstructure (e.g., grain size and orientation) to the ice sheet flow behavior (e.g., borehole tilting and closure). Most impurities in ice form micrometer-sized inclusions. It has been suggested that these µ inclusions control the grain size of polycrystalline ice by pinning of grain boundaries (Zener pinning), which should be reflected in their distribution with respect to the grain boundary network. We used an optical microscope to generate high-resolution large-scale maps (3 µm pix−1, 8 × 2 cm2) of the distribution of micro-inclusions in four polar ice samples: two from Antarctica (EDML, MIS 5.5) and two from Greenland (NEEM, Holocene). The in situ positions of more than 5000 µ inclusions have been determined. A Raman microscope was used to confirm the extrinsic nature of a sample proportion of the mapped inclusions. A superposition of the 2-D grain boundary network and µ-inclusion distributions shows no significant correlations between grain boundaries and µ inclusions. In particular, no signs of grain boundaries harvesting µ inclusions could be found and no evidence of µ inclusions inhibiting grain boundary migration by slow-mode pinning could be detected. Consequences for our understanding of the impurity effect on ice microstructure and rheology are discussed.

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Mele, Andrea, Federica Arrigoni, Catherine Elleouet, François Y. Pétillon, Philippe Schollhammer y Giuseppe Zampella. "Insights into Triazolylidene Ligands Behaviour at a Di-Iron Site Related to [FeFe]-Hydrogenases". Molecules 27, n.º 15 (22 de julio de 2022): 4700. http://dx.doi.org/10.3390/molecules27154700.

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The behaviour of triazolylidene ligands coordinated at a {Fe2(CO)5(µ-dithiolate)} core related to the active site of [FeFe]-hydrogenases have been considered to determine whether such carbenes may act as redox electron-reservoirs, with innocent or non-innocent properties. A novel complex featuring a mesoionic carbene (MIC) [Fe2(CO)5(Pmpt)(µ-pdt)] (1; Pmpt = 1-phenyl-3-methyl-4-phenyl-1,2,3-triazol-5-ylidene; pdt = propanedithiolate) was synthesized and characterized by IR, 1H, 13C{1H} NMR spectroscopies, elemental analyses, X-ray diffraction ,and cyclic voltammetry. Comparison with the spectroscopic characteristics of its analogue [Fe2(CO)5(Pmbt)(µ-pdt)] (2; Pmbt = 1-phenyl-3-methyl-4-butyl-1,2,3-triazol-5-ylidene) showed the effect of the replacement of a n-butyl by a phenyl group in the 1,2,3-triazole heterocycle. A DFT study was performed to rationalize the electronic behaviour of 1, 2 upon the transfer of two electrons and showed that such carbenes do not behave as redox ligands. With highly perfluorinated carbenes, electronic communication between the di-iron site and the triazole cycle is still limited, suggesting low redox properties of MIC ligands used in this study. Finally, although the catalytic performances of 2 towards proton reduction are weak, the protonation process after a two-electron reduction of 2 was examined by DFT and revealed that the protonation process is favoured by S-protonation but the stabilized diprotonated intermediate featuring a {Fe-H⋯H-S} interaction does not facilitate the release of H2 and may explain low efficiency towards HER (Hydrogen Evolution Reaction).

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Mele, Andrea, Federica Arrigoni, Luca De Gioia, Catherine Elleouet, François Y. Pétillon, Philippe Schollhammer y Giuseppe Zampella. "Use of the Asymmetrical Chelating N-Donor 2-Imino-Pyridine as a Redox [Fe4S4] Cubane Surrogate at a Di-Iron Site Related to [FeFe]-Hydrogenases". Inorganics 11, n.º 12 (29 de noviembre de 2023): 463. http://dx.doi.org/10.3390/inorganics11120463.

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Two complexes, related to the active site of [FeFe]-hydrogenases, [Fe2(CO)4(κ2-pma)(µ-bdt)] (1) and [Fe2(CO)4(κ2-pma)(µ-pdt)] (2) (bdt = benzene-1,2-dithiolate, pdt = propane-1,2-dithiolate) featuring the diaza chelate ligand trans-N-(2-pyridylmethylene)aniline (pma) were prepared, in order to study the influence of such a redox ligand, potentially non-innocent, on their redox behaviours. Both complexes were synthesized by photolysis in moderate yields, and they were characterized by IR, 1H and 13C{1H} NMR spectroscopies, elemental analyses and X-ray diffraction. Their electrochemical study by cyclic voltammetry, in the presence and in the absence of protons, revealed different behaviours depending on the aliphatic or aromatic nature of the dithiolate bridge. Density functional theory (DFT) calculations showed the role of the pma ligand as an electron reservoir, allowing the rationalization of the proton reduction process of complex 1.

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Ajibade, Patrick y Stephen M. Mutula. "Information Technology Integration to Promote SMEs Productivities and Sustainability". African Journal of Business and Economic Research 16, n.º 4 (15 de diciembre de 2021): 225–42. http://dx.doi.org/10.31920/1750-4562/2021/v16n4a11.

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Abstract As the Small and Medium-size Enterprises (SMEs) are essential to any nations’ economy, so is the alignment of Information Technologies in improving business agility, sustainability and productivity. The aim of this article is to critically assess the level of business and IT infrastructure alignment with the SMEs. Data were collected from 230 SMEs in Nigeria and South Africa, and statistical software was used to analyse and present results. The findings indicated a lack of partnerships between IT and business units/department (r = -.265), and this negatively affected the SMEs ability to maximise the potential of their employees due to lack or inability of the IT and business department to collaborate (r = -.167) in order to increase operational agility. Furthermore, the SMEs ability to integrate their IT infrastructure with the scope of their IT architecture is very low, but barely above average (µ = 2.98). However, the SMEs compliance with the IT standards were robust (µ = 4.07), with the level of IT alignment with their business processes (µ = 3.08) reaching level three. Furthermore, these firms have developed an established strategy to handle IT disruption to business operations (µ = 3.42), due to a flexible scope of IT infrastructure (µ = 3.47) with their business and IT environment. Nevertheless, the study concluded that the SMEs must achieve between level 4 and 5 of business-IT alignment, to be able to withstand rapid disruption from more sophisticated technologies and volatile business environment.

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Алтунин, Р. Р., Е. Т. Моисеенко y С. М. Жарков. "Влияние структурных свойств на электросопротивление тонких пленок Al/Ag в процессе твердофазной реакции". Физика твердого тела 62, n.º 4 (2020): 621. http://dx.doi.org/10.21883/ftt.2020.04.49130.652.

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Based on the study of a solid-state reaction process in Al/Ag thin films (the atomic ratio being Al:Ag=1:3) carried out by in situ electron diffraction method and electrical resistivity measurements, the reaction initiation temperature has been determined and a model of structural phase transitions occurring during the solid-state reaction has been proposed. The solid-state reaction begins at 70°C with the formation of an Al-Ag solid solution at the interface of aluminum and silver nanolayers. It has been found that in the reaction process intermetallic compounds γ-Ag2Al => µ-Ag3Al are successively formed. It has been established that for the formation of the µ-Ag3Al phase in thin films (up to 100 nm) the following is necessary: first, significant excess of silver over aluminum in the atomic composition, second, the formation of the µ-Ag3Al phase begins only after all the FCC aluminum has reacted. The work was supported by the Russian Science Foundation (grant #18-13-00080).

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Pelluau, Tristan, Saad Sene, Beltzane Garcia-Cirera, Belen Albela, Laurent Bonneviot, Joulia Larionova y Yannick Guari. "Multifunctionalized Mesostructured Silica Nanoparticles Containing Mn2 Complex for Improved Catalase-Mimicking Activity in Water". Nanomaterials 12, n.º 7 (29 de marzo de 2022): 1136. http://dx.doi.org/10.3390/nano12071136.

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We report the synthesis of a hybrid nanocatalyst obtained through the immobilization of bio-inspired [{Mn(bpy)(H2O)}(µ-2-MeC6H4COO)2(µ-O){Mn(bpy)(NO3)}]NO3 compound into functionalized, monodispersed, mesoporous silica nanoparticles. The in situ dual functionalization sol–gel strategy adopted here leads to the synthesis of raspberry-shaped silica nanoparticles of ca. 72 nm with a large open porosity with preferential localization of 1,4-pyridine within the pores and sulfobetaine zwitterion on the nanoparticles’ periphery. These nano-objects exhibit improved catalase-mimicking activity in water thanks to the encapsulation/immobilization of the catalytic active complex and high colloidal stability in water, as demonstrated through the dismutation reaction of hydrogen peroxide.

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Hilmer, Mathias, Sebastian Gruber y Petra Foerst. "Development of a Freeze-Drying Stage for In-Situ µ-CT Measurements". Processes 8, n.º 7 (18 de julio de 2020): 869. http://dx.doi.org/10.3390/pr8070869.

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This paper shows the development of a freeze-drying stage for in-situ μ-CT measurements. The stage can operate in a temperature range of −40 °C up to 70 °C, and a pressure range from atmospheric pressure to 7 Pa at the sample holder. To get the best visualization of the probe, it is fundamental that the materials around the sample holder are not absorbing most of the radiation. For this reason, we built an axial symmetrical stage built out of polyetheretherketon (PEEK). A test of the stage by different freeze-drying experiments with maltodextrin and sucrose particles and solutions demonstrated its suitability to visualize the freeze-drying processes in-situ. It was possible to track the drying front during the process by radiographic and tomographic measurements, as well as to visually resolve the ice crystals and porous structure in tomographic measurements. Using different samples and process parameters, we showed that the freeze-drying stage is not only suitable for in-situ µ-CT measurements, but also allows us to use the stage for other imaging methods such as neutron imaging, and for any sample where a controlled environment is needed.

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Schröder, Guido, Detlef Wendig, Benjamin Jabke, Marko Schulze, Andreas Wree, Günther Kundt, Johannes Manhart et al. "Vergleich der Spongiosamorphologie aus humaner Halswirbelsäule (HWS), Brustwirbelsäule (BWS) und Lendenwirbelsäule (LWS) einer 102-jährigen Körperspenderin". Osteologie 28, n.º 04 (noviembre de 2019): 283–88. http://dx.doi.org/10.1055/a-0997-8059.

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ZusammenfassungOsteoporose-typische Frakturen treten nicht in der Halswirbelsäule auf. Knochenhistologische und QCT-Untersuchungen zeigen eine höhere trabekuläre Dichte in der HWS im Vergleich zu den anderen Wirbelsäulenabschnitten. Mikro-CT-Untersuchungen (µ-CT) aller Wirbelkörper zu dieser Problematik sind uns nicht bekannt. Das Ziel der vorliegenden Untersuchung war der Vergleich von Spongiosa aus allen 24 Wirbelkörpern vom HWK 1 bis zum LWK 5 einer 102-jährigen Körperspenderin hinsichtlich Knochenmineralgehalt (KMG), Trabekeldicke (Tb.Th.) und deren Separation (Tb.Sp.). Mittels Jamshidi-Nadel® wurden die Proben gewonnen. Anschließend erfolgte eine µ-CT Analyse. Der höchste KMG fand sich in der HWS (81,8 ± 37,4 mg/cm3). Der Unterschied zu den anderen Abschnitten der Wirbelsäule – BWS (30,9 ± 27,0 mg/cm3, p = 0,005) und LWS (30,9 ± 19,4 mg/cm3, p = 0,048) war statistisch signifikant. Der Vergleich der Werte zwischen BWS und LWS ergab keinen signifikanten Unterschied (p > 0,05). Bezüglich der Tb. Th. und der Tb. Sp. in HWS, BWS und LWS ließen sich keine signifikanten Unterschiede feststellen (p > 0,05). Auch im Einzelfall einer 102-jährigen ist der mittels µ-CT gemessene KMG der HWS signifikant höher als in den anderen Wirbelsäulenabschnitten.

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Belissont, Rémi, Manuel Munoz, Marie-Christine Boiron, Béatrice Luais y Olivier Mathon. "Germanium Crystal Chemistry in Cu-Bearing Sulfides from Micro-XRF Mapping and Micro-XANES Spectroscopy". Minerals 9, n.º 4 (12 de abril de 2019): 227. http://dx.doi.org/10.3390/min9040227.

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Germanium is considered a critical element, with a demand that has sharply increased due to booming high-technology industries. To understand Ge incorporation mechanisms in natural systems, we investigate Ge speciation in Cu-bearing sulfide minerals using synchrotron X-ray fluorescence (XRF) chemical mapping and Ge K-edge µ-X-ray absorption near-edge structures (µ-XANES) spectroscopy. The samples investigated include (i) a homogeneous chalcopyrite from the Kipushi polymetallic deposit (Central African copperbelt, D.R. Congo) and (ii) a zoned Ge-rich chalcopyrite from the Barrigão Cu deposit (Iberian pyrite belt, Portugal). First, our spectroscopic analysis supports the occurrence of tetrahedrally-coordinated Ge4+ in chalcopyrite, independently from origins or zoning patterns observed for these minerals. Then, based on statistical analyses of XRF chemical maps, we demonstrate that tetravalent germanium most likely incorporates chalcopyrite through the Fe crystallographic site via coupled substitutions with the following form: (2x + 3y)Fe3+ ⟷ (x + 2y)(Ge,Sn)4+ + x(Zn,Pb)2+ + y(Cu,Ag)+, although the presence of lattice vacancies cannot be completely excluded.

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23

Karaki, Fumika, Taro Takamori, Koumei Kawakami, Sae Sakurai, Kyoko Hidaka, Kei Ishii, Tomoya Oki et al. "Discovery of 7-Azanorbornane-Based Dual Agonists for the Delta and Kappa Opioid Receptors through an In Situ Screening Protocol". Molecules 28, n.º 19 (3 de octubre de 2023): 6925. http://dx.doi.org/10.3390/molecules28196925.

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In medicinal chemistry, the copper-catalyzed click reaction is used to prepare ligand candidates. This reaction is so clean that the bioactivities of the products can be determined without purification. Despite the advantages of this in situ screening protocol, the applicability of this method for transmembrane proteins has not been validated due to the incompatibility with copper catalysts. To address this point, we performed ligand screening for the µ, δ, and κ opioid receptors using this protocol. As we had previously reported the 7-azanorbornane skeleton as a privileged scaffold for the G protein-coupled receptors, we performed the click reactions between various 7-substituted 2-ethynyl-7-azanorbornanes and azides. Screening assays were performed without purification using the CellKeyTM system, and the putative hit compounds were re-synthesized and re-evaluated. Although the “hit” compounds for the µ and the δ receptors were totally inactive after purifications, three of the four “hits” for the κ receptor were true agonists for this receptor and also showed activities for the δ receptor. Although false positive/negative results exist as in other screening projects for soluble proteins, this in situ method is effective in identifying novel ligands for transmembrane proteins.

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24

Beck, L., P. C. Gutiérrez, S. Miro y F. Miserque. "Ion beam modification of zinc white pigment characterized by ex situ and in situ µ-Raman and XPS". Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 409 (octubre de 2017): 96–101. http://dx.doi.org/10.1016/j.nimb.2017.04.071.

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25

Alkandari, Mohammed, Stefan Abela, Alessandra Booth y Dirk Bister. "In vitro evaluation of surface characteristics comparing WaterLase (Biolase^®) with tungsten carbide burs for composite removal: a pilot study". Australasian Orthodontic Journal 38, n.º 1 (1 de enero de 2022): 194–201. http://dx.doi.org/10.2478/aoj-2022-0022.

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Abstract Introduction The present ex-vivo study was designed to evaluate the surface roughness and analyse potential adhesive remnants on the enamel surface after composite removal using either an Er:YSGG WaterLase (WL) (Biolase®, Irvine, CA, USA) or a tungsten carbide (TC) bur (Alston, England, UK). Methods An in vitro study was designed using 21 extracted lower premolars. Pre-coated stainless steel brackets (3M Unitek, Monrovia, CA, USA) were bonded on all of the teeth except one, which served as a control. The teeth were allocated into two groups: Group 1 (n = 5), removal of composite with a TC bur. Group 2 (n = 15), removal of composite using the WL. Scanning electron microscope (SEM) imaging and Energy Dispersive X-ray Spectroscopy (EDS) were used to determine the surface roughness and atomic composition of the surfaces. Results Group 1 had a median damage depth of 17.6 µm with a range between 11.5 µ m and 28.7 µ m. Group 2 had a median damage depth of 166.3 µ m, with a range between 86.6 to 263.1 µ m. The depth differences between the two groups were statistically significant (p < 0.001, Mann–Whitney test). The atomic composition of the WL group was similar to sound enamel. The TC group showed a quantitative increase in carbon and silicone by 38.2% and 11.5%, respectively, a decrease in oxygen by 44.1% and an absence of phosphorous and calcium. Conclusion WL is efficient at removing composite from the enamel surface but could result in increased enamel surface roughness in comparison with conventional TC burs.

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Yao, Mian, Xia Ouyang, Jushuai Wu, A. Zhang, Hwa-Yaw Tam y P. Wai. "Optical Fiber-Tip Sensors Based on In-Situ µ-Printed Polymer Suspended-Microbeams". Sensors 18, n.º 6 (5 de junio de 2018): 1825. http://dx.doi.org/10.3390/s18061825.

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Kannengießer, Thomas, Arne Kromm, Jens Gibmeier y Michael Rethmeier. "In-situ-Analyse der Phasenumwandlungskinetik während des Schweißens". Materials Testing 52, n.º 4 (abril de 2010): 204–10. http://dx.doi.org/10.3139/120.110122.

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Weiler, C. "In-situ-Analyse von Pathomechanismen der humanen Bandscheibendegeneration". Der Pathologe 34, S2 (noviembre de 2013): 251–59. http://dx.doi.org/10.1007/s00292-013-1813-y.

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29

Pelosi, Claudia, Filomena Di Stasio, Luca Lanteri, Martina Zuena, Marta Sardara y Armida Sodo. "The “Restoration of the Restoration”: Investigation of a Complex Surface and Interface Pattern in the Roman Wall Paintings of Volsinii Novi (Bolsena, Central Italy)". Coatings 14, n.º 4 (29 de marzo de 2024): 408. http://dx.doi.org/10.3390/coatings14040408.

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(1) Background: The present paper reports the results of the analyses performed on the wall paintings of Room E of the Domus delle Pitture (Room of the Paintings) in the Roman archaeological site of Volsinii Novi (Bolsena, Viterbo, Central Italy) aimed at supporting the recently concluded restoration. (2) Methods: ultraviolet fluorescence photography was conducted to evaluate the conservation state. Painting materials were investigated via portable X-ray fluorescence spectrometer (p-XRF), µ-Raman spectroscopy, cross-section analysis under polarizing microscope, scanning electron microscopy coupled with energy dispersive spectroscopy (SEM-EDS), and Fourier transform infrared (FTIR) spectroscopy. (3) Results: This analysis revealed the presence of traditional pigments used in Roman wall paintings, such as ochres, earths, and Egyptian blue. Additionally, it identified pigments from previous restoration containing titanium and chromium, along with other materials present in the surface and interface of the wall painting containing arsenic, copper, lead, and vanadium, where a bluish alteration was observed. In these samples, µ-Raman spectroscopy detected calcium oxalates but also copper arsenates, likely conichalcite and/or duftite. (4) Conclusions: This result is highly relevant from an analytical point of view and in relation to the restoration decisions. Addressing the irregular bluish stains on the wall paintings poses challenges in understanding, requiring a decision on whether to remove or retain them.

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Kusuma, Yayan Wahyu C., Siti R. Ariati, Rosniati A. Risna, Chika Mitsuyuki, Yoshihisa Suyama y Yuji Isagi. "Seedling Selection Using Molecular Approach for Ex Situ Conservation of Critically Endangered Tree Species (Vatica bantamensis (Hassk.) Benth. & Hook. ex Miq.) in Java, Indonesia". Tropical Conservation Science 12 (enero de 2019): 194008291984950. http://dx.doi.org/10.1177/1940082919849506.

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Ex situ conservation is an important complementary strategy for in situ to conserve endangered plant species. However, the limited areas designated for ex situ conservation such as in botanic gardens have become a great challenge for conservation practitioners and scientists attempting to optimally conserve the genetic diversity of targeted plant species. Our study aimed to assess genetic diversity and structure of wild seedlings of Vatica bantamensis, an endemic and critically endangered dipterocarp from Java (Indonesia). We also estimated genetic differentiation between the wild seedlings and existing ex situ collection and evaluated the genetic diversity preserved in the ex situ collection. Our analysis, using 730 single-nucleotide polymorphisms loci, showed that wild seedlings exhibited higher genetic diversity than the ex situ collection (nucleotide diversity, µ = 0.26 and 0.16, respectively). Significant genetic differentiation was also detected ( FST = 0.32) between wild seedlings and ex situ collection. Furthermore, we found high kinship within the ex situ collection suggesting low genetic diversity since the founding collection. We also detected three distinct genetic clusters from all samples combined (analysis of molecular variance, ϕ = 0.48, p < .001), with two clusters present in the wild seedlings that were not represented in the ex situ collection. We recommend that supplementary collections from the two newly identified genetic clusters in the wild seedlings should be incorporated to increase genetic diversity in the ex situ collection. Furthermore, our study demonstrated that understanding the population genetics of targeted endangered species provides better results for ex situ conservation strategies.

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Luthfiyah, Fety 'Izza. "KEPATUHAN TENAGA KERJA DALAM MENGGUNAKAN APD". Medical Technology and Public Health Journal 3, n.º 1 (19 de marzo de 2019): 37–43. http://dx.doi.org/10.33086/mtphj.v3i1.664.

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Workers when at working area must use (Personal Protective Equipment) PPE, even though the company has implemented technical controls and administrative controls. But, use of PPE at work is still not good. The purpose of this study was to analyse the compliance of workers in using PPE in production department of PT X. this study was an descriptive observational study with a cross sectional study design. The total study population was 30 people with total sampling. Data were by means as of questionnaire. The result of the study were the average age and length of work of workers in production department of PT X were µ = 29,47 ± 4,99 years old and µ = 7,9 ± 3,96 years. Workers in production department of PT X 60% use PPE and 40% not use PPE. The factor that influence compliance with PPE use was comfort of PPE and factors that don’t affect compliance with PPE use were availability of PPE, PPE training, and supervision of PPE. It is recommended for the company need to approach individually to the workers and need to implement a reward policy. Keywords: compliance, PPE, worker, factors

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32

França De Sá, Susana, Carolina Viana y Joana Lia Ferreira. "Tracing Poly(Vinyl Acetate) Emulsions by Infrared and Raman Spectroscopies: Identification of Spectral Markers". Polymers 13, n.º 21 (20 de octubre de 2021): 3609. http://dx.doi.org/10.3390/polym13213609.

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Vinyl emulsions started to be used by artists in paintings at least since the early 1960s, being now present in several artworks worldwide. However, different vinyl formulations can result in distinct behaviours over time, and if some artworks are currently showing a good condition, others already show damages due to the use of compositions more susceptible to degradation. For this reason, it is fundamental to identify the main components in the vinyl acetate-based (VAc-based) emulsion. This work focuses on the molecular study of VAc-based emulsions by infrared and Raman spectroscopies. It aims at deepening the knowledge on the variability of the composite formulation and on the identification of characteristic bands and spectral profiles (identified as spectral markers) for both polymer and additives. To this end, a broad set of vinyl emulsions was gathered, including reference materials, historical commercial brands in use by Portuguese artists, and commercial brands collected from industrial companies. The entire set includes vinyl homopolymers produced for the purpose of the study and known formulations of vinyl homopolymers and copolymers, with and without plasticisers, according to technical data sheets and previous studies. Furthermore, unknown formulations have been included to validate the usefulness of the identified spectral markers. This set has been studied in the form of solid films deposited in glass slides by infrared spectroscopy in attenuated total reflection mode (ATR-FTIR) and micro-Raman spectroscopy (µ-Raman), both conducted in situ. As conclusions, the combined use of ATR-FTIR and µ-Raman proved to be very useful as different spectral markers were detected by each technique, confirming their complementarity. Besides the clear identification of vinyl acetate-based emulsions by both techniques, it was also possible to suggest spectral markers for the copolymerisation of vinyl acetate with vinyl versatate by µ-Raman, the stabilisation of the emulsion with poly(vinyl alcohol) by ATR-FTIR, and the addition of phthalates or benzoates plasticisers by both ATR-FTIR and µ-Raman.

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Al Omar, A., A. Chenaoui, Rachid Dkiouak, Jose María Cabrera y Jose Manuel Prado. "Microstructural Evolution of Two Medium Carbon Microalloyed Steels during Hot Forging Process". Materials Science Forum 500-501 (noviembre de 2005): 155–62. http://dx.doi.org/10.4028/www.scientific.net/msf.500-501.155.

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The main aim of the present investigation was to study the flow behaviour of two medium carbon microalloyed steels under hot forming conditions, and to analyse its microstructural evolution. The dependence of recrystallized grain size (Drec) on the Zener-Hollomon parameter Z shows a bimodal behaviour with transition from single to cyclic dynamic recrystallization. Also we observed that the variation of Drec normalized by Burgers vector (b) with sss normalized by shear modulus ( µ) shows the same bimodal behaviour cited above. The Derby’s universal equation cited in literature for recrystallized grain sizes was not followed; it seems that the presence of fine precipitated particles has a clear effect on this disagreement.

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34

Rubin, A., D. Favier, P. Danieau, J. P. Chambard y C. Gauthier. "Analyse in situ de contact viscoélastique sur polymère vitreux". Matériaux & Techniques 103, n.º 6 (2015): 607. http://dx.doi.org/10.1051/mattech/2015051.

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35

Chygorin, Eduard Nikolaevich, Vladimir Nikolayevich Kokozay, Iryna Vasylivna Omelchenko y Julia Anatoliyivna Rusanova. "Direct synthesis and crystal structure of a novel tetranuclear Co2IIIFe2III Schiff base complex". European Journal of Chemistry 11, n.º 3 (30 de septiembre de 2020): 250–54. http://dx.doi.org/10.5155/eurjchem.11.3.250-254.2014.

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The title compound, tetra(µ-2-3-(2-oxybenzylideneamino)-1-hydroxypropan-2-olato)-4-nitrophenolatedi-cobalt(III)-di-iron(III) dimethylsulfoxidehexasolvate, crystallizes in the monoclinic space group P21/c and represent the first example of heterometallic CoIII-FeIII complex with 3-((5-nitro-2-hydroxybenzylidene)amino)propane-1,2-diol/2-(((2,3-dihydroxy propyl)iminio)methyl)-4-nitrophenolate) - a hydroxyl rich Schiff base ligand which was obtained in situ. Crystal data for C52H74Cl2Co2Fe2N8O26S6 (M = 1720.01 g/mol): monoclinic, space group P21/c (no. 14), a = 16.353(3) Å, b = 15.234(2) Å, c = 15.201(3) Å, β = 113.99(2)°, V = 3460.0(12) Å3, Z = 2, T = 173(2) K, μ(MoKα) = 1.225 mm-1, Dcalc = 1.651 g/cm3, 14130 reflections measured (5.7° ≤ 2Θ ≤ 57.266°), 7748 unique (Rint = 0.1051, Rsigma = 0.2148) which were used in all calculations. The final R1 was 0.0914 (I > 2σ(I)) and wR2 was 0.2279 (all data). The metal ions have distorted octahedral coordination geometry and are joined in a tetranuclear {Co2Fe2(µ-O)6} core by O-bridging atoms from the ligand. There are numerous intermolecular interactions occurring between the components of the crystal: π-hole interaction between NO2···NO2 groups of the ligands, short S···S, O···O and C··· C interactions and weak and strong hydrogen bonds.

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36

Coquet, Y., J. Touma y P. Boivin. "Comparison of soil linear shrinkage curve from extracted cores and in situ". Soil Research 36, n.º 5 (1998): 765. http://dx.doi.org/10.1071/s97098.

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In situ measurement of the linear shrinkage curve (LSC) of soil has been restricted so far to highly swelling clay soils because of the limited precision of thickness measurements of the soil layer. This limitation was eliminated by using electronic displacement transducers that allowed a precision of ±10 µ m on the thickness measurements of 20-cm soil layers. The method was further improved by using block kriging to estimate non-destructively and locally the water content of the soil layer at the same spot where the shrinkage was monitored by the shrinkfiswell gauge. The LSC of 2 weakly swelling soils measured by this method had a shape similar to that of highly swelling soils, although their shrinkage range was 2 orders of magnitude smaller.In situ LSCs of the soil layers were compared with the LSCs of extracted soil cores measured in the laboratory. In situ and laboratory shrinkage curves were significantly different. This discrepancy is thought to be principally due to the rewetting of the soil cores in the laboratory before the shrinkage curve measurement without any mechanical stress applied to their external surfaces.

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37

Trudel, Éric. "La conception néosaussurienne du signe et de la sémiosis et l’analyse des images". Semiotica 2020, n.º 234 (25 de octubre de 2020): 163–75. http://dx.doi.org/10.1515/sem-2018-0127.

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RésuméCet article se propose d’envisager le signe iconique à l’aune du modèle néosaussurien du signe et de la sémiosis qui se dégage des Écrits de linguistique générale. Après avoir exposé ce modèle à partir des propositions que François Rastier tire des textes autographes de Saussure, cette contribution transpose le cadre à la description du signe iconique, en réinterrogeant certains éléments de la conceptualisation que donne le Groupe µ de ce type d’énoncé visuel. Une brève analyse de la toile Le retour à la nature de Magritte permet d’illustrer et de valider la transposition théorique du modèle néosaussurien du signe et de la sémiosis. Cette démarche ouvre la possibilité de procéder à l’interprétation des images selon la théorie morphosémiotique développée par la sémantique de Rastier.

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38

FALIPOU, E., C. BOUTIN, C. FAVRE y R. LACASSE. "Analyse comparée de trois dispositifs d’assainissement à base de fragments de coco". 5, n.º 5 (21 de mayo de 2021): 63–101. http://dx.doi.org/10.36904/tsm/202105063.

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Cet article est centré sur l’analyse de filtres garnis de fragments de coco utilisés en France en assainissement non collectif. La qualité des rejets des trois dispositifs développés (V0, V1 et V2) mesurée en conditions de plateforme d’essais et in situ est comparée. Des études précédentes utilisant une méthodologie d’analyse similaire ont qualifié d’« acceptable » la qualité des rejets in situ de V0 et V2 mais pas celle de V1. L’objectif est d’évaluer l’impact des évolutions techniques (matériau filtrant, surface réduite et distribution) sur les différences observées et de déterminer comment les performances sur plateforme peuvent prédire ces résultats de terrain. Tant pour les résultats recueillis sur plateforme qu’ in situ, les outils statistiques déployés concluent que les meilleures qualités de rejet sont obtenues avec le dispositif V0 et les moins bonnes avec le dispositif V1, le dispositif V2 étant intermédiaire. La comparaison entre la qualité des eaux usées brutes utilisées sur plateforme et celle observée in situ montre des différences de concentrations, mais des charges organiques appliquées plutôt homogènes. Ainsi, il est possible de déterminer les rendements requis sur plateforme, assurant l’atteinte des exigences de rejets in situ. L’article fournit des valeurs de rendement applicables aux dispositifs de configuration équivalente. La distribution améliorée à l’aide de l’auget bidirectionnel explique en partie les meilleures performances de V0 et V2 comparativement à V1. Les diminutions des surfaces de filtration n’ont pas d’impact sur les abattements de composés carbonés. Enfin, bien que sur plateforme les charges surfaciques journalières en azote Kjeldahl (NK) soient plus grandes qu’en conditions in situ, ce type d’essais ne permet pas d’apprécier le vieillissement des dispositifs par l’analyse des différentes concentrations azotées du rejet. La poursuite du suivi in situ apparaît donc pertinente.

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Curetti, Nadia y Alessandro Pavese. "Fe-bearing vanadium dioxide–paramontroseite: structural details and high-temperature transformation". European Journal of Mineralogy 35, n.º 3 (1 de junio de 2023): 373–82. http://dx.doi.org/10.5194/ejm-35-373-2023.

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Abstract. A natural sample of Fe-bearing paramontroseite (V0.84Fe0.19Al0.03O2; a = 4.8960(14), b = 9.395(3), c = 2.9163(5) Å, V = 134.14(6) Å3; space group Pbnm) from Prachovice mine (Czech Republic) was investigated to shed light on cation partitioning and behavior upon heating. XRD experiments showed that V and Fe are not vicariant of one another, as V occupies the octahedral site at (0.09, 0.14, 0.25), whereas Fe enters a tetrahedral site at (0.41, 0.06, 0.25), the latter expected to be empty in the ideal structure. Thermal expansion is anisotropic, leading to the following β coefficients: -2.0×10-5, 3.0×10-5, 0.8×10-5 and 1.8×10-5 ∘C−1 for a, b, c and V, respectively. At T higher than 350 ∘C, V undergoes oxidation, from [4+] to [5+], and paramontroseite decomposes into Fe-tetrapolyvanadate (Fe2V4O13) and V-pentoxide (V2O5). µ-Raman spectroscopy analyses confirmed that paramontroseite is sensitive to heating: the crystal surface invested by the laser beam degrades very quickly, leading to the phases revealed by diffraction measurements. There is no evidence for the formation at high T of a rutile-type phase, as we observed for iso-structural ramsdellite MnO2.

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40

Cutuli, B., R. Fay, C. Cohen-Solal-Le Nir, B. De Lafontan, H. Mignotte, V. Servent, S. Giard et al. "Carcinome canalaire in situ du sein. Analyse de 882 cas". Imagerie de la Femme 15, n.º 1-2 (marzo de 2005): 7–14. http://dx.doi.org/10.1016/s1776-9817(05)80634-0.

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Trouilh, Maria, Dominique Hourdet, Alba Marcellan y Philippe Colomban. "Analyse Raman in situ de la déformation d’un hydrogel nanocomposite". Revue des composites et des matériaux avancés 24, n.º 1 (30 de abril de 2014): 67–79. http://dx.doi.org/10.3166/rcma.24.67-79.

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42

Oberle, Peter, Tim Kerlin, Mark Musall, Thomas Grafmüller y Franz Nestmann. "HIPPO - In-situ-Messgerät zur Analyse der Mobilisierbarkeit von Feinsedimenten". WASSERWIRTSCHAFT 110, n.º 7-8 (agosto de 2020): 20–26. http://dx.doi.org/10.1007/s35147-020-0413-z.

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43

Martínez, Gustavo Aristides Santana, Oscar Rodriguez-Alabanda, Umberto Prisco, Marius Tintelecan y Leonardo Kyo Kabayama. "The influences of the variable speed and internal die geometry on the performance of two commercial soluble oils in the drawing process of pure copper fine wire". International Journal of Advanced Manufacturing Technology 118, n.º 11-12 (18 de octubre de 2021): 3749–60. http://dx.doi.org/10.1007/s00170-021-08172-2.

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AbstractThe cold wiredrawing process constitutes a classical-tribological system in which a stationary tribe-element (die) is in contact with a tribe-element in relative motion (wire) and both interacting with the interfacial tribe-element (lubricant). This condition is reflected in the effect of friction as a function of the drawing speed and temperature, and directly affects the wearing of the surface into the die and the final quality on the drawn wire. The aim of this work has been to determine the best conditions to process ETP-copper using two different types of oil/water emulsion lubricants. For this purpose, six different die geometries have been proposed and a set of tests have been carried out at different speeds (between 1 and 21 m/s) to determine those combinations that give a lower value in the required drawing force (Fd). The experiments allowed to know the friction coefficient (µ), the temperature profile inside the drawing die and in the lubricant and also the mean roughness (Ra) in the drawn product. The results have shown that drawing speeds above 10 m/s significantly decrease the drawing force and, as a consequence, the friction effect on the interface. The best results have been achieved in the combinations of the lower die angle (2β = 14°) with drawing speeds between 17 and 18 m/s with both types of lubricants used, obtaining the lower values of the friction coefficient between µ = 0.10–0.15 with the lubricant type D (Agip S234-60 oil at 7% concentration). It has been found that those tests carried out with dies with a smaller approach angle have generally made it possible to obtain better qualities in the final product. Additionally, FEM simulations have been done to analyse those cases with the lower values of µ, throwing values of Fd that are consistent with those measured in the experimental setting and allowing to better understand the behavior of the material as it passes through the die.

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Aeni, Suci Rizki Nurul, Ni'matul Murtafi'ah y Handarini Handarini. "Chromium(VI) Heavy Metal Biosorption in Citarum River Water Sample Using Saccharomyces cerevisiae and Rhizopus oryzae Biomass". Biogenesis: Jurnal Ilmiah Biologi 8, n.º 2 (30 de diciembre de 2020): 119. http://dx.doi.org/10.24252/bio.v8i2.12274.

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The Citarum River was regarded as the World’s dirtiest river in 2018, characterized by a Basin situated adjacent to several textile and electroplating industries. Hexavalent chromium metal (Cr6+) is a toxic, carcinogenic heavy metal found in the wastes of these industries. Furthermore, biosorption with biological adsorbents, including Saccharomyces cerevisiae and Rhizopus oryzae, is an alternative method for treating water polluted with heavy metals. This study therefore aims to adsorb Cr6 + heavy metals from Citarum River water using S. cerevisiae and R. oryzae biomass in two locations: Nanjung and Pangauban, with various biomass concentrations and stirring speeds. For this study, 0.25, 0.5, and 0.75 g of R. oryzae suspension, as well as 250, 500, and 750 µ of S. cerevisiae were used as adsorbent, while rotated at speeds of 250 rpm, 750 rpm and 1500 rpm. Subsequently, the Cr6 + metal content was measured using a UV-Vis spectrophotometer at a wavelength of 525 nm, and calculated based on a standard curve. The results showed S. cerevisiae and R. oryzae are able to reduce the levels of Cr6+ in Citarum river water. The most reduction was obtained with the highest concentration of the adsorbents, 750 µ for S. cerevisiae and 0.75 g for R. oryzae, at the speed of 1500 rpm. S. cerevisiae and R. oryzae have great potential as biosorbents for the in situ remediation of Citarum River contaminated with heavy metals.

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Sahoo, Niroj Kumar, Sai Bhakti Mishra, Claudio Iovino, Sumit Randhir Singh, Marion R. Munk, Lieselotte Berger, Enrico Peiretti y Jay Chhablani. "Optical coherence tomography angiography findings in cystoid macular degeneration associated with central serous chorioretinopathy". British Journal of Ophthalmology 103, n.º 11 (2 de enero de 2019): 1615–18. http://dx.doi.org/10.1136/bjophthalmol-2018-313048.

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AimTo describe the optical coherence tomography (OCT) characteristics and to identify and analyse the incidence of choroidal neovascular (CNV) network seen on optical coherence tomography angiography (OCTA) in eyes with cystoid macular degeneration (CMD) associated with central serous chorioretinopathy (CSCR).MethodsThis was a retrospective, observational study of 29 eyes of 25 patients who were previously diagnosed as CSCR with CMD. Baseline patient characteristics, best-corrected visual acuity (BCVA), evidence of CNV network and its pattern on OCTA, distribution of CMD changes and OCT parameters, such as height of the neurosensory retinal detachment (NSD), presence of double layer sign, central macular thickness, were analysed. The eyes were classified into two groups depending on the presence or absence of CNV network on OCTA. BCVA, OCT parameters and CMD distribution were compared in the two groups at baseline using independent t-test.ResultA total of 13 (44.8 %) eyes had a CNV network, while only 9 out of the 13 eyes had pattern-I CNV. Among the eyes with CNV network (13 eyes), mean height of NSD was of 65.2±22.7 µ, whereas, among the eyes without CNV (16 eyes), it was 134.6±77.4 µ. The difference was statistically significant (p=0.013). There was no statistically significant difference between eye having a CNV and eyes without CNV in terms of other parameters.ConclusionA CNV network is seen in a large subset of patients with CMD in CSCR. A shallower subretinal fluid may point towards the presence of an underlying CNV network.

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46

Bouchard, Louise y Pierre Doray. "L’évaluation sociale des technologies : articulation pragmatique du technique et du social". Cahiers de recherche sociologique, n.º 35 (27 de abril de 2011): 125–47. http://dx.doi.org/10.7202/1002239ar.

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Le présent article vise à préciser les principales balises de l’évaluation sociale des technologies et d’en dégager certains enjeux. Notre analyse procède en deux temps. Le premier expose, à grands traits, l’institutionnalisation du projet d’évaluation des technologies (Technology Assessment ou TA). Le second décrit la spécificité de l'évaluation sociale des technologies. Nous présentons par la suite les différents moments de l’analyse évaluative (analyse constitutive, analyse in situ et analyse prospective) ainsi que le processus de prise en charge sociale des technologies.

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47

Faizah, Ria, Lilis Sadiyah y Aisyah Aisyah. "Struktur Komunitas dan Preferensi Habitat Ikan Karang pada Terumbu Buatan di Teluk Awang dan Teluk Bumbang, Pulau Lombok". Oseanologi dan Limnologi di Indonesia 5, n.º 1 (9 de julio de 2020): 61. http://dx.doi.org/10.14203/oldi.2020.v5i1.202.

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<strong>Community Structure and Habitat of Coral Fish on Artificial Reef in Awang and Bumbang Bay, Lombok Island</strong>. Artificial reefs which were placed in Teluk Awang and Teluk Bumbang intended to restore habitat fish resources. This paper aims to evaluate the development of artificial reefs in both locations. The activities was conducted in June and December 2015. Data collection included fish and benthic communities, biological parameters (phytoplankton, zooplankton, meroplanton), physical parameters (temperature, salinity, conductivity, pH, turbidity, dissolved oxygen), and chemical parameters waters (nitrates and phosphates). Observation of fish community using SCUBA diving equipment, underwater sheets, stationery and GPS, then visual observations using a modified stationary visual census technique. Visual recorded also used for benthic communities. Water sampling taken on the surface and bottom at depths of 9 m and 11 m using water quality checker. Biological parameters were taken using 60 µ, 300 µ and plankton net sizes 700 µ. Nutrients were observed in the laboratory by taking water samples in situ. Laboratory tests were carried out for nutrients as well as plankton and meroplankton. Benthic communities were categorized into four life forms, namely live coral covered, dead coral, biota (algae and other biota) as well as the abiotic component. Habitat preferences identified through analysis of factors related to fish abundance by principal component analysis method. The results showed that on those artificial reefs in Awang and Bumbang Bay found as many as 8 - 16 species of coral fish belongs to 15 families, dominated by Apogonidae (Archamia fucata), Pomacentridae (Neopomacentrus cyanomos) and Phempherididae (Phempheris oulensis), ranges of the abundance 268 to1088 individual. The ecological index showed low to moderate type of diversity, the dominance index does not indicate the dominance of certain species and the evenness index indicated that the fish dispersal characteristic is quite flat. Fish habitat preference in Awang Bay supported by the presence of algae and other biota, nutrients, and salinity. While in Teluk Bumbang supported by the abundance of fito-zooplankton, dissolved oxygen, and turbidity

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Mangeney, A., C. Lacombe, M. Maksimovic, A. A. Samsonov, N. Cornilleau-Wehrlin, C. C. Harvey, J. M. Bosqued y P. Trávníček. "Cluster observations in the magnetosheath – Part 1: Anisotropies of the wave vector distribution of the turbulence at electron scales". Annales Geophysicae 24, n.º 12 (21 de diciembre de 2006): 3507–21. http://dx.doi.org/10.5194/angeo-24-3507-2006.

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Abstract. We analyse the power spectral density δB2 and δE2 of the magnetic and electric fluctuations measured by Cluster 1 (Rumba) in the magnetosheath during 23 h, on four different days. The frequency range of the STAFF Spectral Analyser (f=8 Hz to 4 kHz) extends from about the lower hybrid frequency, i.e. the electromagnetic (e.m.) range, up to about 10 times the proton plasma frequency, i.e. the electrostatic (e.s.) range. In the e.m. range, we do not consider the whistler waves, which are not always observed, but rather the underlying, more permanent fluctuations. In this e.m. range, δB2 (at 10 Hz) increases strongly while the local angle ΘBV between the magnetic field B and the flow velocity V increases from 0° to 90°. This behaviour, also observed in the solar wind at lower frequencies, is due to the Doppler effect. It can be modelled if we assume that, for the scales ranging from kc/ωpe≃0.3 to 30 (c/ωpe is the electron inertial length), the intensity of the e.m. fluctuations for a wave number k (i) varies like k−ν with ν>≃3, (ii) peaks for wave vectors k perpendicular to B like |sinθkB|µ with µ>≃100. The shape of the observed variations of δB2 with f and with ΘBV implies that the permanent fluctuations, at these scales, statistically do not obey the dispersion relation for fast/whistler waves or for kinetic Alfvén waves: the fluctuations have a vanishing frequency in the plasma frame, i.e. their phase velocity is negligible with respect to V (Taylor hypothesis). The electrostatic waves around 1 kHz behave differently: δE2 is minimum for ΘBV>≃90°. This can be modelled, still with the Doppler effect, if we assume that, for the scales ranging from k λDe>≃0.1 to 1 (λDe is the Debye length), the intensity of the e.s. fluctuations (i) varies like k−ν with ν>≃4, (ii) peaks for k parallel to B like |cosθkB|µ with µ>≃100. These e.s. fluctuations may have a vanishing frequency in the plasma frame, or may be ion acoustic waves. Our observations imply that the e.m. frequencies observed in the magnetosheath result from the Doppler shift of a spatial turbulence frozen in the plasma, and that the intensity of the turbulent k spectrum is strongly anisotropic, for both e.m. and e.s. fluctuations. We conclude that the turbulence has strongly anisotropic k distributions, on scales ranging from kc/ωpe≃0.3 (50 km) to kλDe≃1 (30 m), i.e. at electron scales, smaller than the Cluster separation.

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Virojanadara, Chariya, S. Watcharinyanon, A. A. Zakharov, R. Yakimova y Leif I. Johansson. "Studies of Li Intercalation into Epitaxial Graphene on SiC(0001)". Materials Science Forum 717-720 (mayo de 2012): 653–56. http://dx.doi.org/10.4028/www.scientific.net/msf.717-720.653.

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Detailed studies of Li deposition on monolayer graphene grown on the Si-face SiC surface were performed using LEEM, µ- LEED, PES and ARPES. Li found to intercalate directly after the deposition at room temperature. However, excess Li was also observed on the surface and found to form a compound with carbon atoms. This compound is suggested to give rise to a new (√3x√3) R30° surface reconstruction. After annealing the (√3x√3) R30° reconstruction was vanished and only a (1x1) graphene diffraction pattern was visible. At the same time a sever change was observed on the graphene morphology, especially from the ex-situ grown graphene, i.e. extended area of cracks/wrinkles were observed. These wrinkles/cracks did not disappear even after heating at temperature of 500-1000°C when no Li signal was detected.

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50

Queiroz, Salete L., Alzir A. Batista, Marcio P. de Araujo, Roberto C. Bianchini, Glaucius Oliva, Javier Ellena y Brian R. James. "Dichloro(diphosphine)(2-pyridyl-ketone)ruthenium(II) complexes". Canadian Journal of Chemistry 81, n.º 11 (1 de noviembre de 2003): 1263–69. http://dx.doi.org/10.1139/v03-109.

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Described are the synthesis and characterization of Ru(II) complexes of the type RuCl2L2(N-O), where L2 is either 1,4-bis(diphenylphosphino)butane (dppb) or (PPh3)2, and N-O represents chelated 2-benzoylpyridine (2-bzpy) or 2-acetylpyridine (2-acpy); the Ru presursors used were [RuCl2(dppb)]2(µ-dppb) or RuCl2(PPh3)3. The crystal structure of cis-RuCl2(dppb)(2-bzpy) is presented, and three other RuCl2L2(N-O) complexes with cis-chlorines are isolated and characterized spectroscopically; of the trans-dichloro species, RuCl2(PPh3)2(N-O) complexes are isolated, while the corresponding dppb species are characterized in situ. In all cases, thermodynamically stable cis-complexes are formed from initially formed trans-species.Key words: ruthenium, phosphines, 2-benzoylpyridine, 2-acetylpyridine, X-ray structures.

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