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The relevance of the use of lubricating oil containing carbon nanotubes during the deposition process has been shown. The technique of experimental studies during deposition of cylindrical blanks has been described. Tests were carried out during deformation of the samples printed on a 3D printer. As a result of this experimental study, it has been shown that the introduction of carbon nanotubes into engine oil reduces the friction coefficient. [ABSTRACT FROM AUTHOR]

Bi2Sr2Co2Oy thin films were grown on 10° vicinal-cut Al2O3 (0001) single crystalline substrates by pulsed laser-deposition techniques with in situ annealing, post-annealing and non-annealing process, respectively. The pure phase Bi2Sr2Co2Oy thin film was obtained with a non-annealing process. The result of X-ray diffraction showed that Bi2Sr2Co2Oy thin film was obviously c-axis preferred orientation. The laser-induced thermoelectric voltage signals were detected in Bi2Sr2Co2Oy thin films, which originated from the anisotropy of the Seebeck coefficient. The maximum peak value of laser-induced thermoelectric voltage was strong and could reach as large as 0.44 V and the response time was 1.07 μs when the deposition time was 6 min. Furthermore, the peak voltage enhanced linearly with the single-pulse laser energy. These characteristics demonstrate that Bi2Sr2Co2Oy thin film is also an excellent choice for laser energy/power detectors. [ABSTRACT FROM AUTHOR]

The excellent microstructure and mechanical properties of Al-Cu alloy deposited using the Direct Energy Deposition (DED) process has been shown in previous studies, which is the most likely aluminum alloy material to meet the load-bearing requirements of hypersonic aircraft. However, its high-temperature performance and the law of microstructure transformation during the high-temperature process still need to be determined. In this paper, DED Al-Cu alloy samples were prepared using the Cold Metal Transfer (CMT) process, CMT Pulse process, and CMT Pulse Advanced process. The effect of different deposition processes on the microstructure and mechanical properties of the deposits was investigated at 200 °C for 30 min. The results show that the Al-Cu alloy's main strengthening phase θ′ is excessively transformed into the equilibrium θ phase after the high-temperature process, which is the main reason for the degradation in the DED Al-Cu alloy's properties at high temperatures. Different deposition processes have almost no effect on the high-temperature performance of the DED Al-Cu alloy, and the deposition process can be selected according to the product's structure. [ABSTRACT FROM AUTHOR]

Thin film coatings are extensively used to enhance the physical and chemical properties of various materials by depositing a thin layer of coatings of different materials onto various substrates. Several deposition processes are available which are widely adopted by many manufacturing industries to meet such demands. To exploit the fullest potential of those deposition processes, it is often advised to operate them with the optimal combination of process parameters. In this research, a modified PROMETHEE (preference ranking organisation method for enrichment evaluation) method as an effective multi-objective optimisation tool is applied for identifying the optimal parametric combinations of two thin film deposition processes: silicon carbonitride thin film coating using a thermal chemical vapour deposition process and zirconium-containing diamond-like-carbon thin film coating using an unbalanced magnetron sputtering process. The derived optimal parametric combinations are validated based on developed regression equations, which exhibit that the proposed approach can attain better response values as compared to other popular optimisation techniques. The analysis of variance results and the developed surface plots further illustrate the influence of various deposition parameters on coating quality. [ABSTRACT FROM AUTHOR]

The stratigraphic-diffusive type of gas hydrate system is formed by microbial methane produced in a shallow slope space when flowing laterally into hydrate stable zones and is worth studying for both energy supply and academic understanding. A deposition production model matching the vertical and lateral seabed morphological characteristics was constructed to show the accumulation process, layer timing sequence, and reservoir quality of the stratigraphic-diffusive hydrate system in the Dongsha slope sediments since the Pleistocene. Six representative key system factors at three selected moments (1.5 Ma, 700 ka B.P., and at present) have been exhibited during debris is continuously accumulating. The coexistence of the hydrate decomposition in the lower part and the formation in the upper part, and the uneven distribution of hydrates within the slope sediment surface are explained clearly. By comparing four geological cases with diverse environments, it is shown that the diffusive hydrate system is likely to develop into moderate geological conditions. The most powerful carbon fixation ability in this system was quantified within the time range of 100−50 ka B.P. Finally, it was verified that residual methane would converge near the seafloor interface and then eventually overflow out of the seabed into the seawater. [ABSTRACT FROM AUTHOR]

Copyright of Lubrication Engineering (0254-0150) is the property of Editorial Office of LUBRICATION ENGINEERING and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Engineering Geology / Gongcheng Dizhi Xuebao is the property of Journal of Engineering Geology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Sedimentologica Sinica is the property of Acta Sedimentologica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of this research is to deepen the knowledge of the role of friction on the dynamics of granular media; in particular the friction angle is taken into consideration as the physical parameter that drives stability, motion and deposition of a set of grains of any nature and size. The idea behind this work is a question: is the friction angle really that fundamental and obvious physical parameter which rules stability and motion of granular media as it seems from most works which deal with particle dynamics? The experimental study tries to answer this question with a series of laboratory tests, in which different natural and artificial granular materials have been investigated in dry condition by means of a tilting flume. The characteristic friction angles, both in deposition (repose) and stability limit (critical) conditions, were measured and checked against size, shape, density and roughness of the considered granular material. The flume tests have been preferred to "classical" geotechnical apparatuses (e.g. shear box) since the flume experimental conditions appear closer to the natural ones of many situations of slope stability interest (e.g. a scree slope). The results reveal that characteristic friction angles depend on size and shape of grains while mixtures of granules of different size show some sorting mechanism with less clear behaviour. [ABSTRACT FROM AUTHOR]

Changes in chemical states of amorphous carbon film during ethylene (C2H4) plasma in the floating potential were investigated with multiple‐internal‐reflection infrared absorption spectroscopy (MIR‐IRAS) and deposition rates. IRAS spectra showed that the peaks due to the sp3‐CHX were observed, but no peaks due to sp2‐CHX were observed. The deposition rate due to ethylene plasma was nearly twice that due to methane plasma, in the same way that the number of carbons in an ethylene molecule is twice as that in a methane molecule. It is suggested that the film growth due to ethylene plasma is the same manner of that due to methane plasma; the plasma‐generated hydrocarbon species such as C2H3 and C2H5, which are generated in ethylene plasma, are adsorbed on dangling bonds that are generated by hydrogen abstraction from the deposited film surface. As a result, the deposited film is composed of sp3‐hydrocarbon components. [ABSTRACT FROM AUTHOR]

Dependence of the thin films porosity on substrate temperature and deposition energy is studied using the classical atomistic simulation. It is revealed that pore dimensions increase with the decrease of the energy of deposited atoms. In the case of low-energy deposition up to several percents of cluster volume are available for atoms and small molecules having van der Waals radii less than 0.2 nm. Dimensions of pores can achieve several nanometers. The growth of substrate temperature from 300 to 500 K results in the decrease of porosity. Structural properties of deposited films vary insignificantly with the variation of energy distribution of deposited atoms if the average energy is fixed. [ABSTRACT FROM AUTHOR]

The attractive key-enabling nanotechnology manufacturing technique of atomic layer deposition (ALD) is well-known to deposit ultra-thin, uniform, conformal and pinhole-free nano-films on complex topography. Over the years it has been used to deposit ultra-thin films in a multitude of industry applications such as microelectronics, solar cells, superconductors, fuel cells, and water purification membranes, among other applications. This study investigates the ALD process effects in the fabrication of Al2O3 thin film over the substrate. The mass fraction coverage over the substrate and deposition rate contours in a Gemstar 6 ALD reactor are examined. The analysis technique illustrates the parameter behavior over a Cartesian coordinate sector in a three-dimensional illustration. The governing laws of the conservation of mass, momentum, energy, species, and kinetic chemical reactions are analyzed numerically by ANSYS Fluent and ChemkinPro. The deposition rate profiles correlated with previous experimental findings in the literature, producing an average growth rate of 1.3 Å/cycles. [ABSTRACT FROM AUTHOR]

Low‐dielectric constant (low‐k) material is critical for advanced FinFET technology parasitic capacitance reduction to enable low‐power and high‐performance applications. Silicon Oxycarbonnitride (SiOCN) is one of the most promising low‐k materials for FinFET gate sidewall spacer. The k value of SiOCN can be controlled in the range of 4.1–5.2 by modifying the chemical contents during the deposition process. However, the integration of SiOCN with k value lower than 5.2 for advanced FinFET technology faces substantial challenges associated with the material damage from subsequent manufacturing processes. Here, the authors demonstrate a hybrid low‐k spacer scheme on a fully integrated 7 nm FinFET technology platform, in which SiOCN with k value of 4.5 was successfully integrated along the sidewalls of the gate electrode as spacer while retaining the structural integrity and dielectric properties. Device characterisation on the hybrid low‐k spacer scheme (k = 4.5) demonstrated 12/11% reduction in P/NFET overlap capacitance (COV) and 3% reduction in ring oscillator effective capacitance (CEFF) in comparison to the baseline reference using SiOCN with k value of 5.2 as spacer. Furthermore, reliability characterisation confirmed the dielectric breakdown voltage (VBD) and leakage current (ILKG) of the hybrid low‐k spacer (k = 4.5) were comparable to the baseline reference (k = 5.2), meeting the technology requirements. [ABSTRACT FROM AUTHOR]

An analysis method for atomistic cluster porosity is presented. Porosity and pore radii are calculated from the coordinates of atoms and van der Waals radii. The pore volume is calculated as the maximum volume of a sphere inscribed in a pore. The method is applied to a silicon dioxide thin film prepared by simulation of ion-beam sputtering. The porosity and distribution of pores by radius are calculated. The concentration of pores that are able to contain small molecules is estimated. [ABSTRACT FROM AUTHOR]

The microstructure of coatings deposited under radiation heating in vacuum at different parameters of pulsed glow discharge is studied. It is shown that depending on the length of the pulses of the glow discharge the deposited coatings may have alternating different-thickness chromium carbide layers. [ABSTRACT FROM AUTHOR]

In this paper, four types of deposition control processes such as temperature, pressure, input/output(I/O), and gas were replaced by the Internet of Things(IoT) to analyze the data load and sequence procedure before and after the application of it. Through this analysis, we designed the load balancing in the sensing area of the deposition process by creating the sequence diagram of the deposition process. In order to do this, we were modeling of the sensor I/O according to the arrival process and derived the result of measuring the load of CPU and memory. As a result, it was confirmed that the reliability on the deposition processes were improved through performing some functions of the equipment controllers by the IoT. As confirmed through this paper, by applying the IoT to the deposition process, it is expected that the stability of the equipment will be improved by minimizing the load on the equipment controller even when the equipment is expanded. [ABSTRACT FROM AUTHOR]

This work is devoted to checking of the validity of the results of high-performance modeling of SiO2 film growth. Modeling of the high-energy deposition process shows that the refractive indices of deposited SiO2 films exceed the refractive index of a fused silica substrate. This is entirely supported by the analysis of spectrophotometric data obtained for practical thin films deposited using the respective deposition technique. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Xi'an Polytechnic University is the property of Editorial Department of Journal of Xi'an Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Xi'an Polytechnic University is the property of Editorial Department of Journal of Xi'an Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Supercomputer modeling of the process of high-energy deposition (ion-beam sputtering) of thin films of silicon dioxide using the molecular dynamics (MD) approach was carried out. The deposition method based on the facilities of the LAMMPS MD program was compared with another method that is known from the literature. An analysis of the structure of the deposited film (density, radial distribution function, concentration of defects) was carried out. [ABSTRACT FROM AUTHOR]

Microstructures of combined coatings deposited under radiation heating in vacuum with pulsed ignition of glow discharge are presented. The effect of the heat treatment on the structure and properties of the coatings is studied. [ABSTRACT FROM AUTHOR]

In this work we compare two force fields that are intended for the molecular dynamics simulation of the process of the deposition of silicon dioxide thin films. Analysis of the structural characteristics (the density and radial distribution function) of a glassy silicon dioxide cluster that was used as a substrate and a deposited film is carried out. It is shown that the DESIL force field in which the Van der Waals interaction is described by the Lennard-Jones potential turns out to be more suitable for modeling the process of deposition. [ABSTRACT FROM AUTHOR]

CdTe films have been prepared by close-spaced sublimation under different conditions. When CdTe is deposited at a low temperature, grains with a single predominant growth plane (111) adhere to the substrate and gather into scattered particles. With increasing deposition temperature, the number of CdTe grains on the substrate increases very quickly, the grains begin to form a quasi-continuous film, and (220), (311), (400), and (331) growth planes of CdTe begin to appear. When the deposition temperature and time are increased further, the CdTe grains begin to accumulate, the pin-holes formed initially begin to disappear, and grain boundaries with traces of layer growth can be observed. Different transmittance of samples of different thickness is clearly apparent but changes of the band gap, E, of the CdTe films is negligible. XPS results suggest CdTeO is generated on the CdTe film surface as the deposition time is increased. [ABSTRACT FROM AUTHOR]

Purpose – The permeate flux in microfiltration (MF) declines sharply with time due to membrane fouling, which seriously restricts its use in industrial applications. The purpose of this paper is to investigate particles deposition in MF processes, and propose a three-dimensional numerical model that focuses on particle-fluid flow and considers both permeable boundary conditions and cake deposition. Design/methodology/approach – The two-ways coupling model was solved using Euler-Lagrange methods in which the suspended particle was traced by a hard sphere model and the fluid was simulated using large eddy model. Findings – The numerical results predicted based on this model demonstrated the permeate flux increased as trans-membrane pressure and inlet velocity increased but decreased with an increase in feed concentration. Research limitations/implications – Good agreement was observed between the values obtained with the model and experimental values from the literature. The error is less than 20 per cent both permeate flux and cake thickness. In addition, a precise visualisation of cake morphology with filtration time was provided. Originality/value – These analyses allowed for an estimation of the three-dimensional motion of suspended particles in turbulent flow. It saves manpower and financial resources for experiment, which possess important theoretical and industrial significance. [ABSTRACT FROM AUTHOR]

In this paper we present a computationally effective approach to classical molecular dynamic simulation of thin film growth with orientation on cluster supercomputing facilities. The goal of the developed approach is to investigate structural heterogeneities of thin films deposited on substrates at a nanoscale level. These heterogeneities depend on the experimental conditions of a deposition process being used. They have essential influence on practical properties of thin films and their modeling is important for achieving further progress in thin film optical technology.The presented research is focused on silicon dioxide thin films growth. A special force field, oriented on the atomistic description of the silicon dioxide deposition on fused silica substrate, has been developed and applied to the molecular dynamic simulation with the GROMACS package. The validity of the developed simulation approach is verified using atomic clusters consisting of up to 106 atoms and having characteristic dimensions of up to 30 nm. Its computational efficiency is tested using up to 2048 cores. The dependence of achievable efficiency on model parameters is discussed. [ABSTRACT FROM PUBLISHER]

The processes and process parameters affecting the structure and properties of coatings are reviewed. Microstructures obtained at various deposition parameters are presented. [ABSTRACT FROM AUTHOR]

PECVD of a nanoscale SiO2 capping layer using low pressure SiCl4/O2/Ar plasmas is numerically investigated. The purpose of this capping layer is to restore photoresist profiles with improved line edge roughness. A 2D plasma and Monte Carlo feature profile model are applied for this purpose. The deposited films are calculated for various operating conditions to obtain a layer with desired shape. An increase in pressure results in more isotropic deposition with a higher deposition rate, while a higher power creates a more anisotropic process. Dilution of the gas mixture with Ar does not result in an identical capping layer shape with a thickness linearly correlated to the dilution. Finally, a substrate bias seems to allow proper control of the vertical deposition rate versus sidewall deposition as desired. [ABSTRACT FROM AUTHOR]

The most crucial step in manufacturing organic electronic devices is the deposition of the active organic layers. This deposition is mostly achieved by thermal evaporation of special organic materials out of an evaporation cell in a high‐vacuum environment. The major goal is to produce a thin layer with a well‐defined deposition rate. In this study, a mathematical model of the deposition process is presented and a procedure for identifying the unknown model parameters is given. The model covers the transient evaporation of organic materials as well as the thermal behaviour of the evaporation source. A control law based on the concepts of differential flatness turned out to be superior to conventional control strategies. The controller is tested on a real world high‐vacuum system using two different evaporation materials. Finally, it is demonstrated, that the proposed approach yields improved layer morphologies that are the basis of outstanding device characteristics. [ABSTRACT FROM AUTHOR]

Layer-by-Layer (LBL) self-assembled films of rose bengal (RB) have been fabricated onto quartz substrate by the alternative adsorption of polycation poly (amine hydrochloride) (PAH) and RB. UV-Vis absorption studies reveal the formation of RB dimmer in PAH-RB LbL films. Scanning Electron Micrograph (SEM) picture confirms the aggregation of RB molecules in LbL films. Almost 15 min is required to complete the interaction between RB and PAH molecules in the 1 bilayer LbL film. The dye (RB) was found to come off the film during the subsequent poly cation (PAH) deposition. As an alternative approach RB was anchored to the polycation PAH via physiadsorption and controlling the concentration of the combination of RB and PAH was used as polycation and poly (acrylic acid) (PAA) as polyanion for film deposition. The absorption spectra after each deposition showed that there was no material loss during layer depositions via second method. [ABSTRACT FROM AUTHOR]

In this paper, the relationship between the uniformity measure ( U) and the Taguchi signal-to-noise ratio (SNR) for parameter design (or robust design) is investigated with a focus on the deposition process. For the static parameter design, it can be easily shown that U is directly related to the Taguchi SNR, and, as such, U can be interpreted as a measure directly related to the expected loss after the mean thickness is adjusted to the target. For the dynamic parameter design in which the target of a characteristic (e.g., the target thickness for a deposition process) changes, the Taguchi SNR is conditional on the signal parameter values (e.g., the deposition times) used in the parameter design experiment. Therefore, a new performance measure is developed considering a general distribution of the target thickness, and it is shown that U is also equivalent to this new performance measure. In summary, U can be used as a valid performance measure for the dynamic as well as static parameter design of a deposition process. Based on these findings, static and dynamic parameter design procedures for a deposition process are developed considering not only U but also the deposition rate, and the proposed dynamic procedure is illustrated with an example case study. [ABSTRACT FROM AUTHOR]

The effect of vacuum-plasma coatings of titanium nitride (TiN) on the fatigue strength of titanium VT1-0 is investigated in terms of the coating deposition and thickness parameters. The analysis of the obtained results is performed with the goal of improving the required fatigue strength of the base material-coating composition. It is shown that in all the investigated cases, TiN coatings enhance the fatigue strength. The optimum range of coating thicknesses is established, in which the change in the deposition conditions influences slightly the fatigue limit. A satisfactory agreement is noted between the experimental and calculated values of fatigue limits obtained using the calculation model earlier proposed by the authors. The principal possibility of essential increasing the fatigue strength has been discussed and confirmed in the case of formation of ultra-thin coatings under well-defined conditions of their deposition. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) thin films were prepared by pulsed laser deposition (PLD) technique using XeCl excimer laser with a wavelength of 308 nm at room temperature on quartz and single crystal silicon (100) substrates. The oxygen gas pressure was set at 6 torr during the deposition. The deposited films were post-heat treated (HT) in air at different annealing temperatures (ATs) for 30 min. The X-ray diffraction (XRD), optical and electrical properties were measured to study the properties of the films as a function of AT. XRD analysis showed that the strength of (002) peak increases and full width at the half maximum (FWHM) value decreases as the AT increases from 200 to 600°C. The films HT at higher AT of ∼600°C showed dominant c axis oriented hexagonal wurtize crystal structure. The films HT at 600°C exhibit high average transmittance of ∼85% in the visible region and very sharp absorption edge at 376 nm with energy band gap of ∼3·46 eV. Electrical measurement indicates that the resistivity of films decreases with the AT up to 600°C, after which there is an increase at higher AT. The complex of hydrogen defect and oxygen vacancy in the ZnO films may be the reason for low conductivity in undoped ZnO films. [ABSTRACT FROM AUTHOR]

Carbon-based sensors have been developed to measure the atmospheric neutral atomic oxygen (AO) flux experienced by spacecraft in low Earth orbit. Thin- and thick-film carbon sensor elements were deposited onto an alumina substrate between thick-film gold tracks and silver palladium solder pads. AO flux is deduced by measuring resistance changes as the carbon film erodes and applying a simple theory. A wide range of responses were observed that are dependent on the deposition process and post deposition annealing. The deposition methods used were dc magnetron sputtering, e-beam evaporation, and screen-printing. The sensors tested compare favorably with similar silver-based sensors that have been flown previously on small satellite missions with significant mass/power constraints. [ABSTRACT FROM PUBLISHER]

A deposition process for coating concrete surface was presented in this study. This can be accomplished by feeding a weak direct current between the steel in a concrete and an electrode located in the external solution. The test was conducted using reinforced concrete prism specimens of 10 × 10 × 40 cm. Cracked specimens were immersed in an electrolyte magnesium acetate solution, and were applied with a constant current for 14 days. The results indicate that deposit materials are capable of coating the concrete surface and that this technique is effective for the improvement of the impermeability of concrete materials. [ABSTRACT FROM AUTHOR]

An apparatus for simultaneous deposition of large size double-sided YBCO thin films by sputtering from single inverted cyclindrical target was constructed. Double-sided YBCO thin films on LaAlO3 (100) substrate up to 30 mm in diameter were prepared to test the performance of the apparatus. The microwave surface resistance, Rs (77 K, 10 GHz, 0 T), of the YBCO thin films on both sides of the wafer ranged from 500 to 800 μΩ. Values of Rs (75 K, 145 GHz, 0 T) below 60 mΩ were reached over the area of 20 mm × 15 mm on the wafer. The majority of the wafer area given in percent has Rs (75 K, 145 GHz, 0 T) values in the range of 21.5– 45.5 mΩ. Lateral homogeneity of Rs values in the whole wafer was good enough to well meet the microwave application. [ABSTRACT FROM AUTHOR]

In this paper, the design and fabrication of silicon-based optical waveguides are revisited. The goal is to develop a novel design and deposition process to minimize leakage losses. Interface roughness and Si3N4 stoichiometry are examined. The optical loss is measured and contributions from scattering and absorption are determined [ABSTRACT FROM PUBLISHER]

A comparative study of Y1Ba2Cu3O7− x (YBCOrpar; thin film growth by inverted cylindrical magnetron sputtering and non-magnetron inverted cylindrical sputtering was done. At the total pressure of 40 Pa epitaxial YBCO thin films with good superconducting transition properties and smooth surface were prepared by the magnetron source. Inductive measurements gave $$T_{C_0 }$$ = 89.5 K and Δ TC = 0.5 K. The full width at half maximum (FWHM) value of the rocking curve was 0.18°. The average surface smoothness of the film was 250 Å. With the non-magnetron source at the same total pressure, the superconducting transition properties of the YBCO thin films were not good because of intense bombardment by energetic ions. However, by raising the total pressure to 60 Pa, epitaxial YBCO thin films with good superconducting transition properties and smooth surface could be prepared by non-magnetron inverted cylindrical sputtering— $$T_{C_0 }$$ = 90.5 K, Δ TC = 0.5 K. The FWHM value of the rocking curve was 0.23° and the average surface smoothness of the film was 900 Å. [ABSTRACT FROM AUTHOR]

A simple and versatile chemical solution deposition process is reported to manipulate the wettability properties of copper sheets. The whole process has the advantage of being time-saving low cost and environment-friendly. An adherent silver coating was achieved under optimal conditions. Scanning electron microscopy and X-ray diffraction were used to examine the silver film structure. A confocal microscope was used to record the 3D topography and assess the film roughness of the surface. A dual morphology was revealed, consisting of broad regions with feather-like structured morphologies and some areas with spherical morphologies. Such silver-coated copper samples exhibited a sufficiently stable coating with superhydrophobicity, having a maximum water contact angle of 152°, along with an oleophilic nature. The corrosion behavior of the produced hydrophobic copper under optimal conditions was evaluated by means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) using a 3.5% NaCl solution. The corrosion protection mechanism was elucidated by the proposed equivalent circuits, indicating that the superhydrophobic silver coating acted as an effective barrier, separating the Cu substrate from the corrosive solution. The superhydrophobic coating demonstrated enhanced anti-corrosion properties against NaCl aqueous solution in relation to the copper substrate as indicated from both EIS and potentiodynamic polarization experiments. [ABSTRACT FROM AUTHOR]

With the recent significant advances in micro- and nanoscale fabrication techniques, deposition of diamond-like carbon films on stainless steel substrates has been experimentally achieved. However, the underlying mechanism for the formation of film microstructures has remained elusive. In this study, the growth processes of diamond-like carbon films on AISI 316L substrate are studied via the molecular dynamics method. Effects of substrate bias voltage on the structure properties and sp3 hybridization ratio are investigated. A diamond-like carbon film with a compact structure and smooth surface is obtained at 120 V bias voltage. Looser structures with high surface roughness are observed in films deposited under bias voltages of 0 V or 300 V. In addition, sp3 fraction increases with increasing substrate bias voltage from 0 V to 120 V, while an opposite trend is obtained when the bias voltage is further increased from 120 V to 300 V. The highest magnitude of sp3 fraction was about 48.5% at 120 V bias voltage. The dependence of sp3 fraction in carbon films on the substrate bias voltage achieves a high consistency within the experiment results. The mechanism for the dependence of diamond-like carbon structures on the substrate bias voltage is discussed as well. [ABSTRACT FROM AUTHOR]

Usage of pyrolytic carbon (PyC) to produce mechanical heart valves (MHVs) has led to heart valve replacement being a very successful procedure. Thus, the mechanical properties of employed materials for MHV production are fundamental to obtain the required characteristics of biocompatibility and wear resistance. In this study, two deposition methods of PyC were compared through a multiscale approach, performing three-point bending tests and nanoindentation tests. Adopted deposition processes produced materials that were slightly different. Significant differences were found at the characteristic scale lengths of the deposited layers. Setting changes of the deposition process permitted obtaining PyC characterized by a more uniform microstructure, conferring to the bulk material superior mechanical properties. [ABSTRACT FROM AUTHOR]

The goal of this research was to find the best conditions to prepare titanium dioxide nanotubes (TNTs) modified with gold nanoparticles (AuNPs). This paper, for the first time, reports on the influence of the parameters of cyclic voltammetry process (CV) -based AuNP deposition, i.e., the number of cycles and the concentration of gold salt solution, on corrosion resistance and the capacitance of TNTs. Another innovation was to fabricate AuNPs with well-formed spherical geometry and uniform distribution on TNTs. The AuNPs/TNTs were characterized using scanning electron microscopy, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, and open-circuit potential measurement. From the obtained results, the correlation between the deposition process parameters, the AuNP diameters, and the electrical conductivity of the TNTs was found in a range from 14.3 ± 1.8 to 182.3 ± 51.7 nm. The size and amount of the AuNPs could be controlled by the number of deposition cycles and the concentration of the gold salt solution. The modification of TNTs using AuNPs facilitated electron transfer, increased the corrosion resistance, and caused better adsorption properties for bovine serum albumin. [ABSTRACT FROM AUTHOR]

A model intercomparison of the atmospheric dispersion of cesium‐137 (137Cs) emitted after the Fukushima Daiichi Nuclear Power Plant accident in Japan was conducted to understand the behavior of atmospheric 137Cs in greater detail. The same meteorological data with a fine spatiotemporal resolution and an emission inventory were applied to all models to exclude the differences among the models originating from differences in meteorological and emission data. The meteorological data were used for initial, boundary, and nudging data or offline meteorological field. Furthermore, a horizontal grid with the same resolution as that of the meteorological data was adopted for all models. This setup enabled us to focus on model variability originating from the processes included in each model, for example, physical processes. The multimodel ensemble captured 40% of the atmospheric 137Cs events observed by measurements, and the figure of merit in space for the total deposition of 137Cs exceeded 80. The lower score of the atmospheric 137Cs than that of the deposition originated from the difference in timing between observed and simulated atmospheric 137Cs. Our analyses indicated that meteorological data were most critical for reproducing the atmospheric 137Cs events. The results further revealed that differences in 137Cs concentrations among the models originated from deposition and diffusion processes when the meteorological field was simulated reasonably well. The models with small deposition fluxes produced higher scores for atmospheric 137Cs, and those with strong diffusion succeeded in capturing the high 137Cs concentrations observed; however, they also tended to overestimate the concentrations. Key Points: A model intercomparison of the atmospheric dispersion of 137Cs using identical input data was conductedDeposition and diffusion were key processes responsible for the differences among the models when the meteorological field was reproducedA score‐weighted ensemble‐mean distribution of the atmospheric 137Cs concentration was created [ABSTRACT FROM AUTHOR]

To improve the corrosion resistance and wear resistance of electroless nickel-phosphorus (Ni-P) coating on magnesium (Mg) alloy. Ni-P-Al2O3 coatings were produced on Mg alloy from a composite plating bath. The optimum Al2O3 concentration was determined by the properties of plating bath and coatings. Morphology growth evolution of Ni-P-Al2O3 composite coatings at different times was observed by using a scanning electronic microscope (SEM). The results show that nano-Al2O3 particles may slow down the replacement reaction of Mg and Ni2+ in the early stage of the deposition process, but it has almost no effect on the rate of Ni-P auto-catalytic reduction process. The anti-corrosion and micro-hardness tests of coatings reveal that the Ni-P-Al2O3 composite coatings exhibit better performance compared with Ni-P coating owing to more appropriate crystal plane spacing and grain size of Ni-P-Al2O3 coatings. Thermal shock test indicates that the Al2O3 particles have no effect on the adhesion of coatings. In addition, the service life of composite plating bath is 4.2 metal turnover, suggesting it has potential application in the field of magnesium alloy. [ABSTRACT FROM AUTHOR]