Artículos de revistas: "Nanofils"

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Patolsky, F. "Des nanofils pour détecter les virus". Revue Française des Laboratoires 2005, n.º 369 (enero de 2005): 15. http://dx.doi.org/10.1016/s0338-9898(05)80063-0.

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2

Pichon, L., J. P. Landesman y H. Lhermite. "La microscopie confocale : un support de formation en micro- et nano-électronique au CCMO, pôle CFM de Rennes". J3eA 21 (2022): 1007. http://dx.doi.org/10.1051/j3ea/20221007.

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L’article présente de l’apport de la microscopie confocale dans les formations en micro- et nano-technologies proposées par le CCMO (Centre Commun de Microélectronique de l’Ouest), pôle CFNM de Rennes. Un focus particulier est porté sur l’observation et la caractérisation à l’échelle micro et nanométrique d’objets (composants, nanofils,…) ou de systèmes microélectroniques (architecture physique de microprocesseurs).

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3

Croquette, Michael, Francesco Fogliano, Chao Zhang, Cattleya Dousset, Lucas Judéaux, Benjamin Besga, Antoine Reigue, Benjamin Pigeau y Olivier Arcizet. "Explorer la nano-optomécanique avec des nanofils suspendus". Photoniques, n.º 129 (2024): 42–46. https://doi.org/10.1051/photon/202412742.

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L’utilisation de nanorésonateurs mécaniques ultrasensibles de taille sub-longueur d’onde permet de cartographier la structure du champ électromagnétique à petite échelle grâce à la mesure des forces et des gradients de force qu’il génère. En mesurant optiquement les vibrations transverses de nanofils suspendus en carbure de silicium, il est possible d’établir le champ de force produit par un faisceau laser focalisé ou par un seul photon peuplant une microcavité, mais aussi par les champs électrostatiques à la surface de nanostructures métalliques.

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4

Harmel, J., R. Tan, Ch Capello, Ch Rouabhi, F. Gessinn, J. Schauber, J.-B. Lincelles y M. Respaud. "Les principes de la chimie verte pour une électronique plus durable : une nouvelle approche de la synthèse chimique de nanoparticules d’oxyde de tungstène WO₃ intégrées dans un capteur de gaz". J3eA 23 (2024): 1010. http://dx.doi.org/10.1051/j3ea/20241010.

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Cet article présente une nouvelle approche pour la synthèse de nanofils d’oxyde métallique pour la réalisation de Capteur de gaz à base de nanoparticules. Le nouveau procédé de synthèse chimique est plus fiable et plus facilement réalisable par les étudiants. De plus, le procédé est en accord avec des grands principes de la chimie verte réduisant au minimum le recours et la production des produits dangereux et potentiellement toxiques pour l’homme et l’environnement.

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5

Landesman, J. P., L. Pichon y F. Gouttefangeas. "Manipulation de nanofils de silicium à partir de nano robots". J3eA 16 (2017): 1010. http://dx.doi.org/10.1051/j3ea/20171010.

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6

Zhang, Kaixuan, Wei Fang, Cunjing Lv y Xi-Qiao Feng. "Evaporation of liquid nanofilms: A minireview". Physics of Fluids 34, n.º 2 (febrero de 2022): 021302. http://dx.doi.org/10.1063/5.0082191.

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Evaporation of virus-loaded droplets and liquid nanofilms plays a significant role in the pandemic of COVID-19. The evaporation mechanism of liquid nanofilms has attracted much attention in recent decades. In this minireview, we first introduce the relationship between the evaporation process of liquid nanofilms and the pandemic of COVID-19. Then, we briefly provide the frontiers of liquid droplet/nanofilm evaporation on solid surfaces. In addition, we discuss the potential application of machine learning in liquid nanofilm evaporation studies, which is expected to be helpful to build up a more accurate molecular model and to investigate the evaporation mechanism of liquid nanofilms on solid surfaces.

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7

Alrajhi, Adnan H., Naser M. Ahmed, Mohd Mahadi Halim, Abeer S. Altowyan, Mohamad Nurul Azmi y Munirah A. Almessiere. "Distinct Optical and Structural (Nanoyarn and Nanomat-like Structure) Characteristics of Zinc Oxide Nanofilm Derived by Using Salvia officinalis Leaves Extract Made without and with PEO Polymer". Materials 16, n.º 13 (21 de junio de 2023): 4510. http://dx.doi.org/10.3390/ma16134510.

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This paper reports the optical properties of zinc oxide nanofilm fabricated by using organic natural products from Salvia officinalis leaves (SOL) extract and discusses the effect of the nanocrystal (NC) structure (nanoyarn and nanomat-like structure) on nanofilm optical properties. The surface-active layer of the nanofilm of ZnO nanoparticles (ZnO NPs) was passivated with natural organic SOL leaves hydrothermally, then accumulated on zinc oxide nanorods (ZnO NRs). The nanofilms were fabricated (with and without PEO) on glass substrate (at 85 °C for 16 h) via chemical solution deposition (CSD). The samples were characterized by UV-vis, PL, FESEM, XRD, and TEM measurements. TEM micrographs confirmed the nucleation of ZnO NPs around 4 nm and the size distribution at 1.2 nm of ZnO QDs as an influence of the quantum confinement effect (QCE). The nanofilms fabricated with SOL surfactant (which works as a capping agent for ZnO NPs) represent distinct optoelectronic properties when compared to bulk ZnO. FESEM images of the nanofilms revealed nanoyarn and nanomat-like structures resembling morphologies. The XRD patterns of the samples exhibited the existence of ZnO nanocrystallites (ZnO NCs) with (100), (002), and (101) growth planes. The nanofilms fabricated represented a distinct optical property through absorption and broad emission, as the optical energy band gap reduced as the nanofilms annealed (at 120 ℃). Based on the obtained results, it was established that phytochemicals extracted from organic natural SOL leaves have a distinct influence on zoic oxide nanofilm fabrication, which may be useful for visible light spectrum trapping. The nanofilms can be used in photovoltaic solar cell applications.

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Chen, Zhen, Huiqi Xie, Linfeng Hu, Min Chen y Limin Wu. "Fabrication of novel lamellar alternating nitrogen-doped microporous carbon nanofilm/MoS2 composites with high electrochemical properties". Journal of Materials Chemistry A 5, n.º 43 (2017): 22726–34. http://dx.doi.org/10.1039/c7ta07136a.

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Nitrogen-doped microporous carbon nanofilm/MoS₂ composites (NMC-nanofilm@MoS₂) were synthesized by immersing MOP nanofilms in (NH₄)₂MoS₄ methanol solution and a subsequent annealing process.

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9

Huo, Jiabin, Wei Li y Teng Wang. "Effect of Cr Doping Concentration on the Structural, Optical, and Electrical Properties of Lead Sulfide (PbS) Nanofilms". Coatings 9, n.º 6 (10 de junio de 2019): 376. http://dx.doi.org/10.3390/coatings9060376.

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In this paper, pristine and Cr-doped lead sulfide (PbS) nanofilms were prepared by chemical and deposition methods. From X-ray diffraction (XRD) analysis, all nanofilm samples possessed good crystallinity with a preferential orientation of the (200) crystal plane. As the Cr doping concentration increased, the nanofilm grain size decreased from 71.5 to 18.9 nm. The SEM results revealed that the variation in Cr concentration led to different grain shapes, and the grain size became smaller with the increasing doping concentrations. Optical studies showed that the optical band gap of PbS films increased from 1.21 to 1.60 eV after Cr doping due to the quantum confinement effect; the 2% Cr-doped PbS nanofilm, with an Eg of 1.49 eV, matched the ideal band-gap value. The electrical characterization showed that, for a 2% Cr doping concentration, the Hall mobility and volume carrier concentration of the nanofilm reached the maximum values of 59.6 cm2∙V−1 s−1 and 20.7 × 1016 cm−3 respectively. The 2 at.% Cr-doped PbS nanofilms exhibited the best optical and electrical properties, suitable for solar cell applications.

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10

Zhang, Juan, Donghui Li y Bo Zhang. "Study on Cavitation and Tribological of TiO2 Nano-Film on Bearing Pads Surface". Journal of Nanoscience and Nanotechnology 21, n.º 12 (1 de diciembre de 2021): 5906–11. http://dx.doi.org/10.1166/jnn.2021.19506.

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Bearings play a vital role in the operation of a two-axis system. Long-term bearing use inevitably produce bubbles and frictional damage. Therefore, the protection of bearings is critical for the stable operation of a two-axis system. In this study, a TiO2 nanofilm is used to physically protect a bearing. The discretization method is used to analyse the cavitation process. Cavitation primarily occurs on the front surface of the pad during bearing operation. A finite element analysis of a bearing pad coated and not coated with TiO2 nanofilms shows that TiO2 nanofilms can effectively absorb the cavitation force exerted on pads, thereby reducing inflicted damage. Moreover, the TiO2 nanofilm reduces the friction coefficient of the pad surface, promoting good bearing capacity of the bearing during rotation. The TiO2 nanofilm serves as a protective layer that improves the anti-wear and bearing performance of a two-axis system.

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11

Wang, Guodong, Pengju Wu, Lanlan Guo, Wei Wang, Wenqiang Liu, Yuanyuan Wang, Tingyu Chen, Haohan Wang, Yonghao Xu y Yingli Yang. "Preparation of Au@ZnO Nanofilms by Combining Magnetron Sputtering and Post-Annealing for Selective Detection of Isopropanol". Chemosensors 10, n.º 6 (3 de junio de 2022): 211. http://dx.doi.org/10.3390/chemosensors10060211.

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We demonstrate the highly sensitive and fast response/recovery gas sensors for detecting isopropanol (IPA), in which the Au-nanoparticles-modified ZnO (Au@ZnO) nanofilms act as the active layers. The data confirm that both the response and the response/recovery speed for the detection of IPA are significantly improved by adding Au nanoparticles on the surface of ZnO nanofilms. The gas sensor with an Optimum Au@ZnO nanofilm exhibits the highest responses of 160 and 7 to the 100 and 1 ppm IPA at 300 °C, which indicates high sensitivity and a very low detecting limit. The sensor also exhibits a very short response/recovery time of 4/15 s on the optimized Au@ZnO nanofilm, which is much shorter than that of the sensor with a pure ZnO nanofilm. The mechanisms of the performance improvement in the sensors are discussed in detail. Both the electronic sensitization and the chemical sensitization of the ZnO nanofilms are improved by the modified Au nanoparticles, which not only regulate the thickness of the depletion layer but also increase the amount of adsorbed oxygen species on the surfaces. This work proposes a strategy to develop a highly sensitive gas sensor for real-time monitoring of IPA.

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12

Liu, Lili, Zhenya Meng, Gang Xu, Chenglin He, Xiaozhi Wu y Rui Wang. "Surface Effects on the Properties of Screw Dislocation in Nanofilms". Advances in Materials Science and Engineering 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/6413495.

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The image dislocation method is used to construct the governing equation of dislocations in nanofilms. The classical Peierls-Nabarro equation can be recovered when the thickness of nanofilm is taken to be infinite. In order to determine the core width and Peierls stress of dislocations, the unstable stacking fault energies of Al and Cu nanofilms are calculated via the first-principle methods. It is found that surface effect can increase the Peierls stresses of screw dislocations in Al and Cu nanofilms.

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13

KUMAR, ARUN y ANANDH SUBRAMANIAM. "CRITICAL THICKNESS FOR Nb NANOFILM ON SAPPHIRE SUBSTRATE: AN EXAMPLE TOWARD UNDERSTANDING EVOLUTION OF COHERENT NANOSTRUCTURES". International Journal of Nanoscience 10, n.º 01n02 (febrero de 2011): 351–54. http://dx.doi.org/10.1142/s0219581x11008071.

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On growth beyond critical thickness, interfacial misfit dislocations partially relax the misfit strains in epitaxially grown nanofilms. In this study the stress state and growth of nanofilms are simulated using Finite Element Method (FEM) by imposing stress-free strains, corresponding to the lattice mismatch between Nb nanofilm and Sapphire substrate. On growth of the Nb nanofilm, a triangular network of edge misfit dislocations nucleates at the (0001) Al 2 O 3∥(111) Nb interface. Using a combined simulation of a coherently strained nanofilm and an edge dislocation, the critical thickness for the nucleation of an edge dislocation is determined using an equilibrium energy criterion. Theoretical analyses in literature use only the component of the Burgers vector parallel to the interface, which is an erroneous description of the stress state and energetics of the system. In this investigation the full interfacial edge dislocation is simulated using standard commercially available software and comparisons are made with results available in literature to bring out the utility of the methodology.

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14

Figueiredo, Viviane Maria Gonçalves de, Alecsandro de Moura Silva, Marcos Massi, Argemiro Soares da Silva Sobrinho, José Renato Cavalcanti de Queiroz, João Paulo Barros Machado, Renata Falchete do Prado y Lafayette Nogueira Junior. "Effect of the nanofilm-coated zirconia ceramic on resin cement bond strength". Journal of Dental Research, Dental Clinics, Dental Prospects 16, n.º 3 (15 de noviembre de 2022): 170–78. http://dx.doi.org/10.34172/joddd.2022.029.

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Background. New surface treatments have been proposed to expand the clinical indications of zirconia prostheses. This study aimed to evaluate the effect of silica and fluorine nanofilms on zirconia ceramic on the resin cement bond strength. Methods. Zirconia blocks and discs underwent different surface treatments: untreated zirconia (CON), sandblasted, silica-coated alumina particles (30 µm) (SC), silica nanofilm (SN), and fluorine nanofilm (FN). Nanofilm deposition was performed through plasma enhanced chemical vapor deposition (PECVD). Zirconia surfaces were characterized on disks by morphology (atomic force microscopy, AFM), chemical analysis (x-ray photoelectron spectroscopy, XPS), and contact angle analysis. A silane coupling agent was applied on each treated surface, and a cylinder of resin cement was built up. Half of the specimens in each group were submitted to 6000 thermal cycles (TC). Bond strength was analyzed using the shear test, and the fractographic analysis was performed with stereomicroscopy and SEM/EDS. Statistical analysis was performed through one-way ANOVA and Tukey test in the non-aged and aged specimens. Results. Nanofilms modified the zirconia surface, which became more hydrophilic and chemically reactive. Chemical bonding between Si-O was found in SN, and FN promoted a fluorination process on the ceramic surface, converting zirconia into zirconium oxyfluoride. Specimens of the SN (TC) group failed on pre-testing. FN (TC) bond strength (3.8 MPa) was lower than SC (TC) and CON (TC) after shearing. Adhesive failure predominated in the experimental groups. Silica nanofilm failure occurred after aging. Conclusion. Silica and fluorine nanofilms deposited by PECVD did not promote effective bonding between zirconia and resin cement.

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Udachan, S., S. B. Kolavekar, N. H. Ayachit, L. A. Udachan, S. Siddanna, S. S. Kolkundi y K. Naveen Kumar. "Influence of deposition pressure on electrical properties of silver nanofilms". Low Temperature Physics 51, n.º 1 (1 de enero de 2025): 72–74. https://doi.org/10.1063/10.0034648.

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Silver nanofilms can achieve unique optical, electrical properties and can have better performance relative to other metal films in optical applications. Silver layers are ideal for reflecting and conducting electrodes for nanofilm solar cells. The conductivity of silver nanofilm depends strongly on its electronic structure. Electrical resistivity data as a function of nanofilm thickness were analyzed within the framework of Fuchs–Sondheimer and Mayadas–Shatzkes theories. In the present study, we have evaluated conduction electron mean free path and specularity parameter at different deposition pressures.

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Lu, Xue Bin, Lin Hai Cui y Ming Yuan Ren. "Optimized Technical Characteristics of Polysilicon Nanofilm". Advanced Materials Research 981 (julio de 2014): 875–78. http://dx.doi.org/10.4028/www.scientific.net/amr.981.875.

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In order to take good advantage of polysilicon nanofilm, optimized technical characteristics of the polysilicon nanofilm are very necessary to investigated. In this paper, the polysilicon nanofilms were prepared under different technical parameters, including thickness and doping concentration, which are very important for preparation of the nanofilm. The experimental results of piezoresistive and temperature characteristics show that the optimized technical characteristics are followed, the thickness is about 90nm, and the doping concentration is about 4.1×?1019cm-3 or between 2.0×?1020cm-3 and 4.1×?1020cm-3 from different point of view. The investigations of optimized technical characteristics are very useful for application of the polysilicon nanofilm to piezoresistive sensor.

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17

Durov, O. V. y T. V. Stetsyuk. "Morphology of titanium, zirconium and hafnium nanofilms deposited onto zirconia ceramic at annealing in vacuum". Physics and Chemistry of Solid State 25, n.º 2 (13 de mayo de 2024): 255–62. http://dx.doi.org/10.15330/pcss.25.2.255-262.

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The morphology of titanium, zirconium, and hafnium nanofilms deposited onto zirconia after annealing in vacuum at 1400, 1500, and 1600°C was studied. Nanofilms show a tendency to fragmentation; for titanium it begins at 1400°C, for zirconium and hafnium at 1500°C. At further heating, titanium nanofilm coagulates, while zirconium and hafnium nanofilms interact with the oxygen of the substrate. Tendencies for the formation of swellings on films prior to fragmentation and a certain role of grain boundaries in the cases of titanium and hafnium were noted.

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Kuzmenko, A. P., I. S. Kashkin, A. I. Kolpakov, A. I. Zhakin y Vi M. Yemelyanov. "Structural and morphological features of magnetron nanofilms of TaN with different thicknesses". Proceedings of the Southwest State University. Series: Engineering and Technology 14, n.º 3 (24 de septiembre de 2024): 147–64. http://dx.doi.org/10.21869/2223-1528-2024-14-3-147-164.

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Purpose of research. Study of morphological and phase changes in the structure of tantalum nitride nanofilms formed by magnetron reactive sputtering on a silicon substrate.Methods. Magnetron sputtering on a silicon substrate was performed using the MVU TM-Magna T setup with the sputtering time parameter changing from 300 to 900 sec, and also with constant power parameters of 500 W and working gas pressure of Ar 0,5 Pa. The morphological and phase changes in the structure of tantalum nitride nanofilms were studied using atomic force microscopy and X-ray phase analysis. The fractal dimension was determined using the cube counting method. X-ray diffractometric analysis in the in situ measurement mode with discrete heating (in 100 °C increments) in air up to 1000 °C using the PAAR HTK-16 high-temperature attachment.Results. Using atomic force microscopy methods, it was found that the granulometric distribution of nanoclusters in the studied TaN nanofilms was Gaussian and an increase in the lateral size of particles was observed with an increase in the deposition time. The nanofilm with a deposition time of 300 s had minimal roughness. The statistical fractal dimension was calculated, the value of which corresponded to their three-dimensionality. According to the X-ray phase analysis data, the sizes of the coherence region, texturing, microdeformations and interplanar deformation distortions were determined, and a mixed Stranski-Krastanov mechanism of nanofilm formation was established.Conclusion. The surface roughness of nitride nanofilms formed at a constant power (500 W) depends significantly on the magnetron sputtering time and N2 concentration. In all studied nanofilm structures, the dominant growth mechanism was the mixed Stranski–Krastanov mechanism.

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Salaün, A.-C., R. Rogel, E. Jacques y L. Pichon. "Fabrication et caractérisation électrique d'un capteur de gaz à base de nanofils de silicium suspendus". J3eA 13 (2014): 0007. http://dx.doi.org/10.1051/j3ea/2014007.

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20

Wang, Bingchen y Lei Li. "Direct observation of the double-layering quantized growth of mica-confined ionic liquids". Nanoscale 13, n.º 42 (2021): 17961–71. http://dx.doi.org/10.1039/d1nr05437f.

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Double-layering quantized growth of IL nanofilms are directly observed under AFM. Based on the equilibrium nanofilm topographies, a double-layering model describing the molecular structure of IL cations and anions on the mica surface is proposed.

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21

Suvorov, Stepan V. y Olesya Yu Severyukhina. "Change in the size of C 60 fullerites during their deposition onto a solid substrate". Himičeskaâ fizika i mezoskopiâ 26, n.º 1 (2024): 60–68. http://dx.doi.org/10.62669/17270227.2024.1.6.

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Nano-sized films are of great interest for such important industries as mechanical engineering and instrument making. Nanofilms themselves can be constructed from various elements and compounds; however, one of the most promising components used to create nanofilms is C60 fullerene and its compounds. C60 fullerites are molecular crystals in the nodes of which C60 fullerenes are located. It was fullerite C60 that was taken as the basic element of the nanofilm, the deposition of which was simulated in this work. An iron Fe(100) crystal was modeled as the substrate on which the nanofilm was deposited. The temperatures, at which the deposition and formation of the "substrate-nanofilm" system were studied, were 300 K, 700 K, 1150 K. Since the research was carried out at the level of nano-sized objects, the modeling was carried out using the molecular dynamics methods in the LAMMPS software package. The main result of the study is that the influence of temperature and the process of the interaction of C60 fullerites with each other and with the substrate on the size of the C60 fullerites themselves after their deposition on the substrate has been established.

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Wu, Xueke, Weiqi Huang, Zhongmei Huang, Chaojie Qin y Yanlin Tang. "The energy band structure of Si and Ge nanolayers". Modern Physics Letters B 30, n.º 34 (8 de diciembre de 2016): 1650402. http://dx.doi.org/10.1142/s0217984916504029.

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First-principles calculation based on density functional theory (DFT) with the generalized gradient approximation (GGA) were carried out to investigate the energy band gap structure of Si and Ge nanofilms. Calculation results show that the band gaps of Si(111) and Ge(110) nanofilms are indirect structures and independent of film thickness, the band gaps of Si(110) and Ge(100) nanofilms could be transfered into the direct structure for nanofilm thickness of less than a certain value, and the band gaps of Si(100) and Ge(111) nanofilms are the direct structures in the present model thickness range (about 7 nm). Moreover, the changes of the band gaps on the Si and Ge nanofilms follow the quantum confinement effects. It will be a good way to obtain direct band gap emission in Si and Ge materials, and to develop Si and Ge laser on Si chip.

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Kuzmin M.V. y Mittsev M.A. "Effect of Friedel Oscillations on the Work Function of Ytterbium Nanofilms". Physics of the Solid State 65, n.º 6 (2023): 1036. http://dx.doi.org/10.21883/pss.2023.06.56121.48.

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The effect of standing waves of charge density (Friedel oscillations) generated by an interface of the metallic ytterbium nanofilm single-crystal silicon substrate type on the work function of ytterbium nanolayers has been studied. It is shown that in the range of nanofilm thicknesses from 0 to 8 monatomic layers, the work function has an oscillating character. This feature of the dependence of the work function on the nanofilm thickness is a consequence of the fact that the standing waves change nonmonotonically the power (momentum) of the electric double layer, which exists on the metal surface and affects the work function of the metal. This ultimately determines the oscillating nature of the dependence of the work function on the thickness of the nanofilms. Keywords: surface, nanofilm, work function, Friedel oscillations, electric double layer, ytterbium.

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SHAIK, JAMEEL, JAVEED SHAIKH MOHAMMED, MICHAEL J. MCSHANE y DAVID K. MILLS. "BEHAVIOR OF ARTICULAR CHONDROCYTES ON NANOENGINEERED SURFACES". Nano LIFE 03, n.º 03 (septiembre de 2013): 1342001. http://dx.doi.org/10.1142/s1793984413420014.

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In tissue engineering, surface modification has becomes one of the leading methods to enhance initial cell attachment and subsequent cellular growth, differentiation and tissue formation. This work studied growth and behavior of primary bovine articular chondrocytes on self-assembled multilayer nanofilms composed of: polyelectrolytes [poly(styrene sulfonate) (PSS), poly-L-lysine (PLL), poly-D-lysine (PDL), chondroitin sulfate (CS), poly(ethyleneimine) (PEI), poly(dimethyldiallylammonium chloride) (PDDA), poly(ethylene glycol) amine (PEG - NH 2)] and proteins [bovine serum albumin (BSA), collagen, fibronectin, laminin]. These biomaterials were used to build mono-, bi-, and tri-layer nanofilm architectures. Potential cytotoxic effects were assessed using Live/Dead assay and cell proliferation was quantified using MTT assay. Bright field and fluorescence microscopy were used to analyze chondrocyte morphology. ImageJ software was used to analyze the number, mean area, circularity and Feret's diameter of viable cells. Cumulative results demonstrated that chondrocyte growth; proliferation and functionality were dependent on initial cell density, nanofilm thickness and material composition of nanofilms.

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Yoshida, Kentaro, Tetsuya Ono, Takenori Dairaku, Yoshitomo Kashiwagi y Katsuhiko Sato. "Preparation of Hydrogen Peroxide Sensitive Nanofilms by a Layer-by-Layer Technique". Nanomaterials 8, n.º 11 (15 de noviembre de 2018): 941. http://dx.doi.org/10.3390/nano8110941.

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H2O2-sensitive nanofilms composed of DNA and hemin-appended poly(ethyleneimine) (H-PEI) were prepared by a layer-by-layer deposition of DNA and H-PEI through an electrostatic interaction. The (H-PEI/DNA)5 film was decomposed by addition of 10 mM H2O2. H2O2-induced decomposition was also confirmed in the hemin-containing (PEI/DNA)5 in which hemin molecules were adsorbed by a noncovalent bond to the nanofilm. On the other hand, the (PEI/DNA)5 film containing no hemin and the (H-PEI/PSS)5 film using PSS instead of DNA did not decompose even with 100 mM H2O2. The mechanism of nanofilm decomposition was thought that more reactive oxygen species (ROS) was formed by reaction of hemin and H2O2 and then the ROS caused DNA cleavage. As a result (H-PEI/DNA)5 and hemin-containing (PEI/DNA)5 films were decomposed. The decomposition rate of these nanofilms were depended on concentration of H2O2, modification ratio of hemin, pH, and ionic strength.

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Fan, Senping, Tianyu Yan, Lihong Huang, Liwen Sang, Yang Mei, Leiying Ying, Baoping Zhang y Hao Long. "Effect of stress on thermal properties of AlGaN nanofilms". Semiconductor Science and Technology 37, n.º 12 (3 de noviembre de 2022): 125006. http://dx.doi.org/10.1088/1361-6641/ac9e18.

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Abstract Aluminum gallium nitride (AlGaN) nanofilms have been widely applied as active layers in ultra-violet opto-electronic devices and power electronics. Stress plays essential role in AlGaN based devices, especially in high electron mobility transistor. Therefore, it is necessary to investigate the thermal properties of AlGaN nanofilms with various stresses. In this work, biaxial stressed [0001] oriented AlGaN nanofilms were studied. The phonon dispersion, density of states, velocity and heat capacity were simulated based on the elastic theory. Thermal conductivities of AlGaN nanofilms, which was found 1 ∼ 2 orders of magnitude lower than the bulk materials, were then calculated by Boltzmann transport equation. Due to the modification of phonon dispersion and increasing of group velocity by tensile stress, the thermal conductivities of AlGaN nanofilms increase from compressive stress (−15 GPa) to tensile stress (+15 GPa). Moreover, a phonon energy gap appears in AlN nanofilm of −15 GPa, which disrupts the linear relation between thermal conductivity and stresses. Our work confirmed that the stress could be promising to tune the thermal conductivity of AlGaN nanofilms.

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Кузьмин, М. В. y М. А. Митцев. "Влияние осцилляций Фриделя на работу выхода нанопленок иттербия". Физика твердого тела 65, n.º 6 (2023): 1082. http://dx.doi.org/10.21883/ftt.2023.06.55670.48.

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The effect of standing waves of charge density (Friedel oscillations) generated by an interface of the ‘metallic ytterbium nanofilm  single-crystal silicon substrate’ type on the work function of ytterbium nanolayers has been studied. It is shown that in the range of nanofilm thicknesses from 0 to 8 monatomic layers, the work function has an oscillating character. This feature of the dependence of the work function on the nanofilm thickness is a consequence of the fact that the standing waves change nonmonotonically the power (momentum) of the electric double layer, which exists on the metal surface and affects the work function of the metal. This ultimately determines the oscillating nature of the dependence of the work function on the thickness of the nanofilms.

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28

Luniov, S. V., P. F. Nazarchuk y O. V. Burban. "Electrical properties of strained germanium nanofilm". Physics and Chemistry of Solid State 22, n.º 2 (28 de mayo de 2021): 313–20. http://dx.doi.org/10.15330/pcss.22.2.313-320.

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Dependences of the concentration of intrinsic current carriers, electron and hole mobilities and specific conductivity for strained germanium nanofilms grown on the Si, Ge(0,64)Si(0,36) and Ge(0,9)Si(0,1) substrates with crystallographic orientation (001), on their thickness at different temperatures were calculated on the basis of the statistics of non-degenerate two-dimensional electron and hole gas in semiconductors. The electrical properties of such nanofilms are determined by the peculiarities of their band structure. It is established that the effects of dimensional quantization, the probability of which increases with decreasing temperature, become significant for germanium nanofilms with the thickness of d<7 nm. The presence of such effects explains the significant increase in the specific conductivity and the decrease in the intrinsic concentration of current carriers for these nanofilms. The electron and hole mobility in the investigated germanium nanofilms is lower in relation to such unstrained nanofilms. Only for the strained germanium nanofilm with the thickness of d> 50 nm grown on the Ge(0,9)Si(0,1) substrate, an increase in the hole mobility at room temperature of more than 1.5 times was obtained. The obtained results of the electrical properties of strained germanium nanofilms can be used in producing on their basis new elements of nanoelectronic.

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29

Reszka, Kazimierz, Jan Rakoczy y Jerzy Morgiel. "Application of SEM/TEM to Tests on Pt Distribution in Al₂O₃ Films Obtained by Oxidising FeCrAl Steel Foil Coated with Pt-Al Nanofilms". Advances in Science and Technology 66 (octubre de 2010): 23–28. http://dx.doi.org/10.4028/www.scientific.net/ast.66.23.

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Good dispersion of active catalytic elements, their uniform distribution on the carrier’s surface and availability for neutralised combustion gases are key factors that determine the usability of catalyst cartridges for automotive catalytic reactors. By examining the morphology of oxide films, with SEM/STEM method, obtained by oxidation of foil coated with Pt/Al two-layered system (like laminate), where an Al nanofilm is situated between steel foil and a Pt nanofilm, one can observe forked and plate whiskers growing directly of substrate. Oxide films obtained from Pt+Al composite nanofilms were formed differently (where components are intermixed). These films are marked by chaotic, mutually penetrating fine equiaxed solids and whiskers. In case of composite nanofilms the grain system obtained in the course of deposition contributed to good Pt grain refining, and due to that mostly particles from 3 to 9 nm in conventional diameter were formed. Direct contact between Pt particles and Al particles caused the partial occlusion of Pt particles with oxide in the process of Al oxidation to be effected.

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30

Wang, Ling, Ai Hong Deng, Kang Wang, Yong Wang, Xiao Bo Lu, Yuan Wang y Ran Li. "The Evolution Behavior of Defects in the Nanofilms of W/Cu and W Probed by Doppler Broadening Positron Annihilation Spectroscopy". Defect and Diffusion Forum 373 (marzo de 2017): 104–7. http://dx.doi.org/10.4028/www.scientific.net/ddf.373.104.

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W/Cu multilayer nanofilms and pure W nanofilms were prepared in pure Ar and He/Ar mixing atmosphere by radio frequency magnetron sputtering method. The defect evolution of the samples was characterized by Doppler broadening positron annihilation spectroscopy (DB-PAS).The results show that plenty of defects can be produced by introducing helium (He) into W/Cu multilayer nanofilms. With the natural storage time increasing, the helium located in the near surface of W/Cu multilayer nanofilm would be released gradually and induce the coalescence of the helium related defects due to the diffusion of the helium and defects. In addition, the pure W nanofilms were irradiated by 30 keV helium ions and 40 keV hydrogen (H) ions in sequence at room temperature. From the DB-PAS analysis, it can be shown that a large number of vacancy-type defects are produced due to the He and/or H irradiation. H ions would be trapped by He related defects and produced He-H-V complexes.

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31

Lubenchenko, A. V., A. A. Batrakov, D. A. Ivanov, O. I. Lubenchenko, I. A. Lashkov, A. B. Pavolotsky, B. Schleicher, N. Albert y K. Nielsch. "Air-oxidation of Nb Nano-Films". Физика и техника полупроводников 52, n.º 5 (2018): 529. http://dx.doi.org/10.21883/ftp.2018.05.45873.62.

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AbstractX-ray photoelectron spectroscopy (XPS) depth chemical and phase profiling of air-oxidized niobium nanofilms has been performed. It is found that oxide layer thicknesses depend on the initial thickness of the niobium nanofilm. The increase in thickness of the initial Nb nano-layer is due to increase in thickness of an oxidized layer.

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32

Pang, Ilsun, Sungsoo Kim y Jaegab Lee. "Significantly Improved Adhesion of Poly(3,4-ethylenedioxythiophene) Nanofilms to Amino-Silane Monolayer Pre-Patterned SiO2 Surfaces". Journal of Nanoscience and Nanotechnology 7, n.º 11 (1 de noviembre de 2007): 3792–94. http://dx.doi.org/10.1166/jnn.2007.028.

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This study reports a novel patterning method for highly pure poly(3,4-ethylenedioxythiophene) (PEDOT) nanofilms having a particularly strong adhesion to a SiO2 surface. An oxidized silicon wafer substrate was micro-contact printed with n-octadecyltrichlorosilane (OTS) monolayer, and subsequently its negative pattern was self-assembled with three different amino-functionalized alkylsilanes, (3-aminopropyl)trimethoxysilane (APS), N-(2-aminoethyl)-3-aminopropyltrimethoxy silane (EDAS), and (3-trimethoxysilylpropyl) diethylenetriamine (DETS). Then, PEDOT nanofilms were selectively grown on the aminosilane pre-patterned areas via the vapor phase polymerization method. To evaluate the adhesion and patterning, the PEDOT nanofilms and SAMs were investigated with a Scotch® tape test, contact angle analyzer, optical and atomic force microscopes. The evaluation revealed that the newly developed bottom-up process can successfully offer a strongly adhered and selectively patterned PEDOT nanofilm on an oxidized Si wafer surface.

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33

Pang, Ilsun, Sungsoo Kim y Jaegab Lee. "Significantly Improved Adhesion of Poly(3,4-ethylenedioxythiophene) Nanofilms to Amino-Silane Monolayer Pre-Patterned SiO2 Surfaces". Journal of Nanoscience and Nanotechnology 7, n.º 11 (1 de noviembre de 2007): 3792–94. http://dx.doi.org/10.1166/jnn.2007.18074.

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This study reports a novel patterning method for highly pure poly(3,4-ethylenedioxythiophene) (PEDOT) nanofilms having a particularly strong adhesion to a SiO2 surface. An oxidized silicon wafer substrate was micro-contact printed with n-octadecyltrichlorosilane (OTS) monolayer, and subsequently its negative pattern was self-assembled with three different amino-functionalized alkylsilanes, (3-aminopropyl)trimethoxysilane (APS), N-(2-aminoethyl)-3-aminopropyltrimethoxy silane (EDAS), and (3-trimethoxysilylpropyl) diethylenetriamine (DETS). Then, PEDOT nanofilms were selectively grown on the aminosilane pre-patterned areas via the vapor phase polymerization method. To evaluate the adhesion and patterning, the PEDOT nanofilms and SAMs were investigated with a Scotch® tape test, contact angle analyzer, optical and atomic force microscopes. The evaluation revealed that the newly developed bottom-up process can successfully offer a strongly adhered and selectively patterned PEDOT nanofilm on an oxidized Si wafer surface.

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34

Min-Dianey, Kossi Aniya Amedome, Top Khac Le, Jeong Ryeol Choi y Phuong V. Pham. "Advanced Optical Detection through the Use of a Deformably Transferred Nanofilm". Nanomaterials 11, n.º 3 (23 de marzo de 2021): 816. http://dx.doi.org/10.3390/nano11030816.

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Graphene has been extensively investigated in advanced photodetection devices for its broadband absorption, high carrier mobility, and mechanical flexibility. Due to graphene’s low optical absorptivity (2.3%), graphene-based photodetection research so far has focused on hybrid systems to increase photoabsorption. However, such hybrid systems require a complicated integration process and lead to reduced carrier mobility due to heterogeneous interfaces. Crumpled or deformed graphene has previously been reported in electronics and optoelectronics. However, a depth study on the influence of the morphology of nanofilms (e.g., graphite or graphene) related to light absorption in photodetection devices has not been demonstrated yet. Here, we present an interesting study in terms of the effect of the deformable surface and the smooth surface of a nanofilm transferred onto Si through two transfer strategies using isopropanol injection and nitrogen blowing (to form a deformable nanofilm surface) and deionized water injection and van der Waals interaction (to form a smooth nanofilm surface). As a result, optical detection in the case of the deformable nanofilm surface was enhanced significantly (~100%) compared with that of the smooth nanofilm surface in the visible laser wavelength (532 nm). In addition, evidence from the computational simulation also firmly affirms an advancement in the optical detection of deformed nanofilm-surface-based photodetection devices compatible with the experimental results.

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35

Liu, Wen-Jen, Yung-Huang Chang, Yuan-Tsung Chen, Yi-Chen Chiang, Ding-Yang Tsai, Te-Ho Wu y Po-Wei Chi. "Effect of Annealing on the Characteristics of CoFeBY Thin Films". Coatings 11, n.º 2 (20 de febrero de 2021): 250. http://dx.doi.org/10.3390/coatings11020250.

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In this study, the addition of Y to CoFeB alloy can refine the grain size to study the magnetic, adhesion and optical properties of as-deposited and annealed CoFeB alloy. XRD analysis shows that CoFeB(110) has a BCC CoFeB (110) nanocrystalline structure with a thickness of 10–50 nm under four heat-treatment conditions, and a CoFeB(110) peak at 44° (2θ). The measurements of saturation magnetization (MS) and low frequency alternate-current magnetic susceptibility (χac) revealed a thickness effect owed to exchange coupling. The maximum MS of the 300 °C annealed CoFeBY film with a thickness of 50 nm was 925 emu/cm3 (9.25 × 105 A/m). The maximum χac value of the 300 °C annealed CoFeBY nanofilms with a thickness of 50 nm was 0.165 at 50 Hz. After annealing at 300 °C, CoFeBY nanofilms exhibited the highest surface energy of 31.07 mJ/mm2, where the thickness of the nanofilms was 40 nm. Compared with the as-deposited CoFeBY nanofilms, due to the smaller average grain size after annealing, the transmittance of the annealed nanofilms increased. Importantly, when a CoFeB seed or buffer layer was replaced by a CoFeBY nanofilm, the thermal stability of the CoFeBY nanofilms was improved, promoting themselves on the practical MTJ applications.

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36

Wu, Kunlin, Ding Zhang, Minghua Liu, Qi Lin y Bing-Chiuan Shiu. "A Study on the Improvement of Using Raw Lacquer and Electrospinning on Properties of PVP Nanofilms". Nanomaterials 10, n.º 9 (31 de agosto de 2020): 1723. http://dx.doi.org/10.3390/nano10091723.

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Raw lacquer (RL), ethanol being used as the solvent, was added to polyvinyl pyrrolidone (PVP) and then electrospun into RL/PVP nanofilms. Manufacturing parameters such as RL/PVP ratio, voltage, flow velocity, needle type, and the distance between syringe and the collection board were systematically investigated. A scanning electronic microscope (SEM) was used to observe the surface morphology of nanofilms; the block drop method was used to measure the water contact angle; the mechanical properties of RL/PVP nanofilms of different proportions were tested by universal material testing machine; and Fourier-transform infrared spectroscopy (FT-IR) was used to characterize the structure. Based on the water resistance and acid resistance measurements, the proposed nanofilms demonstrated to be water and acid resistant were successfully produced. The results show that PVP that melts in water becomes incompatible with water after adding raw lacquer, and the acid resistance is greatly improved. Furthermore, the smaller the fiber diameter, the better the mechanical properties of the nanofilms are under low ratio of RL/PVP. With a high proportion of RL/PVP, the inner structure of the nanofilm is denser, and the water resistance and acid resistance are better. The dense structure can protect the inner material of the nanofilms.

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37

Yan, Guangyuan, Tong Wu, Shuming Xing, Fei Chen, Biwei Zhao y Wenjing Gao. "Ultrathin Ce-doped La₂O₃ nanofilm electrocatalysts for efficient oxygen evolution reactions". Nanotechnology 33, n.º 24 (25 de marzo de 2022): 245405. http://dx.doi.org/10.1088/1361-6528/ac5b55.

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Abstract It is still highly desired to develop efficient, resource-abundant and inexpensive electrocatalysts to improve the sluggish kinetics of oxygen evolution reaction (OER) in electrochemical water splitting systems. In this work, the large-area ultrathin (2.52 nm thick) Ce-doped La2O3 nanofilms were developed via a facile and reliable ionic layer epitaxy method with different Ce content. The ultrathin Ce-doped La2O3 nanofilm with optimum composition of La1.22Ce0.78O3 exhibited an excellent OER performance with a very low overpotential of 221 mV at 10 mA cm−2 and a small Tafel slope of 33.7 mV dec−1. A remarkable high mass activity of 6263.2 A g−1 was also obtained from ultrathin La1.22Ce0.78O3 nanofilm at the overpotential of 221 mV. Such a high mass activity was three orders of magnitude higher than state-of-the-art commercial IrO2 powders (3.8 A g−1) and more than 30 times higher than La2O3 nanofilm (196.7 A g−1) without Ce doping at the same overpotential. This high mass activity was even significantly higher than other recently reported typical OER catalysts. The substantial OER performance gain by the Ce doping was attributed to the improved conductivity and electrochemical active surface areas of nanofilms as a result of favorable tuning on the charge transfer and electronic structures. This work provides a promising approach to develop high-performance two-dimensional (2D) electrocatalysts by effective heteroatom doping strategy.

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38

Song, Chunli, Zhanbin Jin, Fengyan Li, Miaomiao Zhen, Lu Xi y Lin Xu. "Enhanced photocatalytic performance of bismuth vanadate assisted by polyoxometalates and phthalocyanine". New Journal of Chemistry 42, n.º 24 (2018): 19678–84. http://dx.doi.org/10.1039/c8nj04378g.

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H₃PW₁₂O₄₀ (PW₁₂) and binuclear phthalocyanine (bi-CoPc) modified nanofilms PW₁₂–BiVO₄–bi-CoPc were prepared. Under illumination of visible light, PW₁₂–BVO–bi-CoPc nanofilm exhibits a 3-fold enhancement in photocatalytic degradation of NO₂.

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39

Shim, Jee-Soo, Dong-Hyun Go y Hyeon-Gyu Beom. "Effects of Geometric and Crystallographic Factors on the Reliability of Al/Si Vertically Cracked Nanofilm/Substrate Systems". Materials 14, n.º 13 (25 de junio de 2021): 3570. http://dx.doi.org/10.3390/ma14133570.

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In this study, tensile tests on aluminum/silicon vertically cracked nanofilm/substrate systems were performed using atomistic simulations. Various crystallographic orientations and thicknesses of the aluminum nanofilms were considered to analyze the effects of these factors on the reliability of the nanofilm/substrate systems. The results show that systems with some specific crystallographic orientations have lower reliability compared to the other orientations because of the penetration of the vertical crack into the silicon substrate. This penetration phenomenon occurring in a specific model is related to a high coincidence of atomic matching between the interfaces in the model. This high coincidence leads to a tendency of the interface to maintain a coherent form in which the outermost silicon atoms of the substrate that are bonded to the aluminum nanofilm tend to stick with the aluminum atoms under tensile loads. This phenomenon was verified by interface energy calculations in the simulation models.

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40

Yu, Zhiqiang, Jinhao Jia, Xinru Qu, Qingcheng Wang, Wenbo Kang, Baosheng Liu, Qingquan Xiao, Tinghong Gao y Quan Xie. "Tunable Resistive Switching Behaviors and Mechanism of the W/ZnO/ITO Memory Cell". Molecules 28, n.º 14 (10 de julio de 2023): 5313. http://dx.doi.org/10.3390/molecules28145313.

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A facile sol–gel spin coating method has been proposed for the synthesis of spin-coated ZnO nanofilms on ITO substrates. The as-prepared ZnO-nanofilm-based W/ZnO/ITO memory cell showed forming-free and tunable nonvolatile multilevel resistive switching behaviors with a high resistance ratio of about two orders of magnitude, which can be maintained for over 103 s and without evident deterioration. The tunable nonvolatile multilevel resistive switching phenomena were achieved by modulating the different set voltages of the W/ZnO/ITO memory cell. In addition, the tunable nonvolatile resistive switching behaviors of the ZnO-nanofilm-based W/ZnO/ITO memory cell can be interpreted by the partial formation and rupture of conductive nanofilaments modified by the oxygen vacancies. This work demonstrates that the ZnO-nanofilm-based W/ZnO/ITO memory cell may be a potential candidate for future high-density, nonvolatile, memory applications.

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41

Li, Yan, Chuan Xin Zhai y Chun Hua Xu. "Microstructure Characterization of Rapid Solidification Al Alloy Foil". Materials Science Forum 694 (julio de 2011): 847–50. http://dx.doi.org/10.4028/www.scientific.net/msf.694.847.

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The AlMn and AlMnSi foils were fabricated by rapid solidification technology. The phase transformation temperatures, microstructures and distribution of elements were characterized by Differential Scanning Calorimetry (DSC), Transmission Electron Microscope (TEM), X-ray Diffraction (XRD) and Energy Disperse Spectroscopy (EDS) respectively. The result shows that the phases of AlMn7 nanofoil conclude Al, Al6Mn and quasicrystal phase, the crystal size is about 120nm; the phases of AlMn5Si5 nanofoil conclude Al, Al4.01MnSi0.74 and Al9Mn3Si, the crystal size is about 60nm. The phase transformation temperatures of AlMn7 and AlMn5Si5 nanofoils are 543K and over 873K, respectively. The microstructure morphology of AlMn7 nanofoil are rod, block and petal-like, but the microstructure morphology of AlMn5Si5 nanofoil is homogeneous globular.

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42

Barati, Mohammad Reza. "Porosity-dependent vibration and dynamic stability of compositionally gradient nanofilms using nonlocal strain gradient theory". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 232, n.º 17 (5 de septiembre de 2017): 3144–55. http://dx.doi.org/10.1177/0954406217729421.

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Porosity-dependent free vibration and dynamic stability of functionally graded nanofilms are studied according to the nonlocal strain gradient theory. Two-scale coefficients are considered to incorporate both nonlocality and strain gradient impacts. The nanofilm is subjected to in-plane hygro-thermal and harmonic mechanical loads. Uniform dispersion of porosities is considered according to a power-law model for functionally graded materials. Galerkin's approach is employed to obtain the vibration frequencies as well as stability regions. One can see that stability regions and vibration frequencies of a functionally graded nanofilm are significantly affected by static load parameter, dynamic load parameter, porosities, moisture change, temperature change, and elastic substrate nonlocal strain gradient coefficients.

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43

GUO, JIAN-GANG y YA-PU ZHAO. "THE SURFACE- AND SIZE-DEPENDENT ELASTIC MODULI OF NANOSTRUCTURES". Surface Review and Letters 14, n.º 04 (agosto de 2007): 667–70. http://dx.doi.org/10.1142/s0218625x07010044.

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A theoretical model is presented to investigate the size-dependent elastic moduli of nanostructures with the effects of the surface relaxation surface energy taken into consideration. At nanoscale, due to the large ratios of the surface-to-volume, the surface effects, which include surface relaxation surface energy, etc., can play important roles. Thus, the elastic moduli of nanostructures become surface- and size-dependent. In the research, the three-dimensional continuum model of the nanofilm with the surface effects is investigated. The analytical expressions of five nonzero elastic moduli of the nanofilm are derived, and then the dependence of the elastic moduli is discussed on the surface effects and the characteristic dimensions of nanofilms.

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44

Huang, Lihong, Senping Fan, Liwen Sang, Yang Mei, Leiying Ying, Baoping Zhang y Hao Long. "Thermal conductivity and phonon scattering of AlGaN nanofilms by elastic theory and Boltzmann transport equation". Semiconductor Science and Technology 37, n.º 5 (18 de marzo de 2022): 055003. http://dx.doi.org/10.1088/1361-6641/ac5293.

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Abstract Aluminum gallium nitride (AlGaN) plays an essential role in deep ultra-violet light emitting diodes and high electron mobility transistors etc. For example, 2 nm – 5 nm AlGaN nanofilms consist of the quantum wells in ultra-violet light emitting diodes, which have been attracting extensive attention since the rise of COVID 2019. Since most photons and heat are generated in these AlGaN nanofilms, the thermal properties of AlGaN nanofilms are strongly influenced by the heat dissipation of devices. In this paper, utilizing elastic theory and the Boltzmann transport equation, the phonon dispersion relations, density of states, specific heat capacities and thermal conductivities of 2 nm Al δ Ga1−δ N nanofilms with various δ are theoretically calculated at different temperatures. The thermal conductivity of nanofilm is significantly smaller than that of its bulk counterpart. In contrast with bulk AlGaN, due to the dominance of boundary scattering and alloy disorder scattering, the thermal conductivity of Al δ Ga1−δ N exhibits a similar dependence on Al concentration to bulk Al δ Ga1−δ N. Meanwhile, since the screening of Umklapp scattering, the saturation temperature of thermal conductivity is delayed from 50 to 100 K in bulks to about 300 K in nanofilms. The shrinkage of nanofilms’ thermal conductivity is also slower than for bulks. We believe that our work will be helpful in controlling the self-heating effect of devices based on AlGaN nanofilms.

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45

YIN Yue, DOU Lin, SHEN Tian-Ci, LIU Jia-Tong y GU Fu-Xing. "Laser trapping and manipulation of micro/nano-objects on polymer substrates". Acta Physica Sinica 74, n.º 8 (2025): 0. https://doi.org/10.7498/aps.74.20241654.

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Polymer substrates overcome the limitations of rigid planar substrates in spatial deformation scenarios and can be combined with photolithography to fabricate complex, three-dimensional irregular polymer structures. Photothermal-shock tweezer is a laser trapping technique based on the photothermal shock effect. Photothermal-shock tweezer leverages pulsed laser induced transient photothermal shock to generate micro-newton-scale thermomechanical strain gradients force, enabling the capture and manipulation of micro/nano-objects at solid interfaces. Integrating this technique with polymer substrates can address the demands of new application scenarios.In this work, we use commonly employed polymethyl methacrylate (PMMA) and negative photoresist (SU-8) as polymer substrates, on which SiO2 nanofilms are fabricated using the sol-gel method. This approach effectively mitigates thermal damage caused by photothermal shock effects, enabling laser trapping and manipulation of micro/nano-objects. SiO2 nanofilms, characterized by low thermal conductivity, effectively inhibit heat transfer. The nanofilm fabrication technique utilized in this study enables the synthesis of large-area SiO2 nanofilms with large-area coverage, low surface roughness (Rq ~ 320 pm) and uniform thickness, making it broadly applicable to flexible polymer substrates and irregular structures. Direct contact between the polymer layer and micro/nano-objects during photothermal shock tweezers manipulation can induce irreversible substrate degradation due to transient photothermal shock effects. Experimental results demonstrate that depositing an SiO2 nanofilm thicker than 110 nm on the polymer substrate significantly enhances thermal insulation and protection, effectively mitigating laser-induced damage under typical optical manipulation conditions. Additionally, by analyzing the temperature field distribution of the gold nanosheet, PMMA substrate, and SiO2 nanofilm during a single photothermal shock trapping of a gold nanosheet, we found that the SiO2 nanofilm can reduce the PMMA surface temperature by at least 111 ºC and delay the time for PMMA to reach its peak temperature by 13.2 ns compared to the peak temperature time of the gold nanosheet. The experimental results expand the environmental media for laser trapping of objects, offering new possibilities for applications in micro/nano-manipulation, micro/nanorobotics, and micro/nano-optoelectronic devices.

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46

Wang, Yan, Sunghoon Lee, Haoyang Wang, Zhi Jiang, Yasutoshi Jimbo, Chunya Wang, Binghao Wang et al. "Robust, self-adhesive, reinforced polymeric nanofilms enabling gas-permeable dry electrodes for long-term application". Proceedings of the National Academy of Sciences 118, n.º 38 (13 de septiembre de 2021): e2111904118. http://dx.doi.org/10.1073/pnas.2111904118.

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Robust polymeric nanofilms can be used to construct gas-permeable soft electronics that can directly adhere to soft biological tissue for continuous, long-term biosignal monitoring. However, it is challenging to fabricate gas-permeable dry electrodes that can self-adhere to the human skin and retain their functionality for long-term (>1 d) health monitoring. We have succeeded in developing an extraordinarily robust, self-adhesive, gas-permeable nanofilm with a thickness of only 95 nm. It exhibits an extremely high skin adhesion energy per unit area of 159 μJ/cm2. The nanofilm can self-adhere to the human skin by van der Waals forces alone, for 1 wk, without any adhesive materials or tapes. The nanofilm is ultradurable, and it can support liquids that are 79,000 times heavier than its own weight with a tensile stress of 7.82 MPa. The advantageous features of its thinness, self-adhesiveness, and robustness enable a gas-permeable dry electrode comprising of a nanofilm and an Au layer, resulting in a continuous monitoring of electrocardiogram signals with a high signal-to-noise ratio (34 dB) for 1 wk.

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47

Salatin, Sara, Mitra Alami-Milani y Mitra Jelvehgari. "Expert design and optimization of a novel buccoadhesive blend film impregnated with metformin nanoparticles". Therapeutic Delivery 11, n.º 9 (septiembre de 2020): 573–90. http://dx.doi.org/10.4155/tde-2020-0066.

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Aim: The purpose of this study was to design a metformin nanoparticles (NPs)-loaded buccoadhesive film for enhanced drug bioavailability. Materials & methods: The NPs were prepared and incorporated into a hydroxypropyl methylcellulose-chitosan blend film. Three levels of a three-factor, Box–Behnken design were used to evaluate the critical formulation variables. The drug permeation was also examined using sheep buccal mucosa. Results & conclusion: The results verified the formation of spherical NPs with an average size of 177.8 ± 6.42 nm and entrapment efficiency of 78.03 ± 0.23%. The optimum conditions for nanofilms were predicted to be: hydroxypropyl methylcellulose (700 mg), glycerol (50 mg) and chitosan (0.15 %w/v). The nanofilm showed a high drug permeation within 6 h. The metformin nanofilm offers an excellent opportunity for buccal drug delivery.

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48

Fedotov, Aleksey Yu, Olesya Yu Severyukhina, Anastasia Yu Salomatina y Anatolie S. Sidorenko. "Simulation of the formation and the study of the nanofilm properties of Co-Fe-Nb nanofilms". Himičeskaâ fizika i mezoskopiâ 26, n.º 2 (2024): 179–93. http://dx.doi.org/10.62669/17270227.2024.2.16.

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The article presents the study of the formation and the analysis of the structure and properties of nanomaterials, which are cobalt-iron-niobium thin-film systems. A mathematical model is presented that allows to describe the combined behavior of atomic spins and coordinates. The generalized version of the model can use any type of the force interaction potential and take into account various contributions to the magnetic Hamiltonian depending on the specific problem being solved. When conducting computational experiments, the force potential of the modified embedded atom method (MEAM) was considered; to take into account magnetic interactions, a simplified magnetic Hamiltonian that includes the exchange interaction and the Zeeman interaction was used. The implementation of the mathematical model is presented in the LAMMPS software package, which was used to carry out numerical calculations. During the computational experiments, two separate problems were considered. In the first problem, the processes of deposition, interaction and ordering of a multilayer atomistic cobalt-iron-niobium system were analyzed. It has been shown that when niobium atoms are deposited onto a substrate, a relief nanofilm with irregularities up to a nanometer in height is formed. The contact between iron and niobium nanofilms is more blurred compared to the similar area of the contact between cobalt and iron nanofilms. In the second problem, the self-organization and reorientation of atomic spins in an iron nanofilm with a crystalline structure were analyzed. Calculations were carried out with and without an existing external magnetic field. The appearance of skyrmions (vortex flows) during the spin interaction of iron atoms was recorded. The simulation has shown that under the influence of an external magnetic field, an induced magnetic moment appears in the iron nanofilm, opposite to the induction vector of the external field.

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Митцев, М. А. y М. В. Кузьмин. "Электростатическая природа размерных зависимостей адсорбционных свойств нанопленок иттербия, выращиваемых на поверхности кремния: система CO-Yb-Si(111)". Физика твердого тела 60, n.º 7 (2018): 1416. http://dx.doi.org/10.21883/ftt.2018.07.46133.024.

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AbstractThe adsorption of CO molecules onto ytterbium nanofilms with their thickness varying from 1 to 16 monolayers is studied. The dependences of the number of adsorbed CO molecules (adsorption isotherms) and the work function of ytterbium films on the dose of carbon monoxide are examined. It is demonstrated that both the number of adsorbed molecules and the work function depend (under equal conditions) on the nanofilm thickness; in other words, a size effect is revealed. It is found that this size effect is induced by the electrostatic interaction between the conduction electrons of ytterbium and the electrons localized on the nanofilm surface, which establish bonding between the surface and CO molecules. This interaction depends on the film thickness and limits the number of CO molecules that may be adsorbed onto the surface of a film with a given thickness.

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Vakhrushev, A. V., A. Yu Fedotov, Yu B. Savva y A. S. Sidorenko. "Modeling the processes of atom structure formation of a superconducting spin valve". PNRPU Mechanics Bulletin, n.º 2 (15 de diciembre de 2020): 16–27. http://dx.doi.org/10.15593/perm.mech/2020.2.02.

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The paper considers the modeling of a multilayer nanocomposite, the combination of elements of which gives rise to a spin valve effect. The relevance and importance of effects in the field of spintronics and related materials and devices are described. We study the composition and atomic structure of individual layers of a multilayer nanocomposite, as well as the composition and morphology of the interface of nanocomposite layers. We analyzed a sample with a periodic superconductor-ferromagnet structure consisting of more than 20 alternating layers of niobium and cobalt. The deposition process took place in a deep vacuum. The simulation was carried out by the molecular dynamics method using the potential of the modified immersed atom method. The formation of layers was carried out in a stationary mode. The temperature was adjusted using the Nose-Hoover thermostat. The deposition of each nanofilm ended with a relaxation stage for the necessary stabilization and restructuring of the formed nanocomposite. Three deposition temperature regimes were considered: 300 K, 500 K, and 800 K. For these modes, we analysed the atomic structure of nanofilms and transition regions (interface) formed between the layers. A study of the atomic structure of nanofilms showed that niobium is formed by crystalline regions of different orientations. A cobalt nanofilm is characterized by a structure close to amorphous. The structural features of the interface between the superconductor-ferromagnet layers largely depend on a relief of the surface onto which the deposition is made. The smallest variation in atomic composition is observed in the first niobium-cobalt contact zone, since the formation of the first nanofilm occurs on an even plane of the substrate. An analysis of the influence of the temperature regime during the formation of the nanosystem shows the dependence of the processes of formation of multilayer nanofilm formation, the interface of nanolayers, as well as the composition and morphology of heterostructures on the temperature at which a nanocomposite is manufactured. An increased temperature leads to the formation of a more rarefied structure of nanolayers and an increase in the zones of the interface of nanolayers due to the diffusion of atoms of the sprayed materials.

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