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Received 17 December 2019; accepted 17 June 2020 This work investigated the elastic responses of a composite laminate shell subjected to a transverse low-velocity impact. The governing equation based on the equations of motion of both the impactor and target was developed to detetrmine the impact force. The displacement of the shell subjected to unit impulse loading was solved using the finite element method. A non-linear differential equation in terms of the indentation depth was derived by incorporating the Hertzian contact law and theory of convolution. Runge-Kutta method was employed to solve the non-linear integro-differential equation, leading to the determination of the impact force at the point of contact between the impactor and the composite shell. The elastic responses including the displacement and stress of the composite laminate shell were evaluated using the finite element method by exerting the impact force on the apex of the composite shell. Present approach was verified with the analytical, experimental and numerical results reported in the existing literatures. The influences of stacking sequence of the composite laminate shell on the impact responses were examined through a series of parametric studies. In addition, impact responses of the spherical shells with different materials such as steel, aluminum and glass were studied.

Titanium (Ti) surface, with an essentially bioinert character, is not easy to actively initiate interactions with surrounding biological tissue. In this study, we developed a novel surface modification to enhance the osteogenic response to Ti surface in orthopedic and dental implant applications. The proposed surface modification combined alkaline treatment and type I collagen immobilization through using a natural cross-linker genipin. A variety of experiments were used to characterize the resulting surfaces in terms of morphology, chemistry, roughness, hydrophilicity, and bioactivity. We also assessed the responses of human bone marrow mesenchymal stem cells (hMSCs) to Ti surfaces in terms of adhesion, migration, proliferation, mineralization, and differentiation. Results showed that the modified Ti surfaces revealed a hydrophilic (water and diiodomethane contact angles

Gyroid structures exhibiting interconnected porosity and mean curvature of zero have the closest resemblance to native bone. Interconnected Ti6Al4V pores of different sizes such as 250, 300, 350 and 400 µm were designed and fabricated using selective laser melting (SLM). The fabricated samples were analysed for microstructure using Scaning electron microscopy and phases using X-ray Diffraction. The prevailing trend of decrease in compressive strength with increase in pore size was observed during compression tests; among all the pore sizes, 250 µm pore size showed an excellent compressive strength of 205 MPa. The biocompatibility of such porous structures for bone tissue engineering was evaluated using Human mesenchymal stem cells (hMSCs) through Alamar Blue® assay and visualization of cytoplasm and nucleus using fluorescence microscopy. Gyroid scaffold with pore size 350 and 400 µm displayed the highest biocompatibility; however, 250 µm pore size demonstrated an optimum combination of overall mechanical and biological properties viable for practical applications.

The objective in this study was to enhance osteogenic responses (in vitro and in vivo) to roughened titanium (Ti) dental implants through the formation of superhydrophilic TiO2 nanonetwork surface structure. Sandblasting and acid etching (SLA) was used to roughen the Ti surface. An electrochemical anodization process was then used to form a superhydrophilic TiO2 nanonetwork on the SLA Ti surfaces. The pore size of the nanonetwork structure ranged from a few nanometers to more than 100 nm, which is on the same scale as many biological species. Human bone marrow mesenchymal stem cells were used as an in vitro test model. The TiO2 nanonetwork structure was shown to have a significantly positive effect on hydrophilicity, protein adsorption, cell adhesion, cell migration, cell mineralization, and the gene and protein expression of osteogenic markers. The osseointegration of an anodized SLA screw-type Ti dental implant was investigated in vivo via implantation in the femur of New Zealand white rabbits for durations of 4 or 12 wk. The presence of a superhydrophilic surface TiO2 nanonetwork was shown to significantly enhance the bone-to-implant contact of the roughened SLA screw-type Ti dental implants. Overall, the proposed superhydrophilic TiO2 nanonetwork structure on the roughened SLA Ti surface proved highly effective in enhancing osteogenic responses in vitro and in vivo.

New method for producing a fine powder from commercial soluble coffee using a spray freeze-drying (SFD) technique was investigated. The analysis of aromatic compounds was carried out by headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry. Scanning electron microscopy and laser particle size analysis were used to characterize the physical structure and size distribution of the SFD-derived particles, respectively. Moreover, the moisture content and color of the SFD powder were evaluated. Eleven key volatile compounds were identified in the commercial soluble coffee pre- and post-SFD. Recoveries of aromatic volatiles ranging from 46.8–100.6% were observed in the overall flavor profile from the SFD-obtained powder. The particles of the aromatic powder were spherical in nature with highly porous surfaces and a mean diameter of 18.7 μm. The moisture content of the SFD coffee powder was 4.96%. The total color difference and chroma were 10.74±0.82 and 31.94±0.11, respectively. This study showed that the SFD technique can be potentially employed for the production of soluble coffee with improved product characteristics.

Barium titanate nickelate (BTN) nanorod (NR)-based resistive random access memory (RRAM) has been demonstrated by using the hydrothermal method. The prepared BTN NR materials have the advantages of ease of fabrication, low temperature application, ability to grow various materials, and relative cost effectiveness. In addition, the BTN NR-based RRAM displayed a highly repeatable and forming-free bipolar resistive switching behavior with an ON/OFF ratio of over 105. The resistive switching behavior may be related to the oxygen vacancies on the surface of the BTN NRs, giving rise to the formation of straight and extensible conducting filaments along each vertically aligned BTN NR. Compared to its counterpart of BTN thin film, superior reproducibility was also observed, demonstrating that the nanostructured material provides an effective way to improve the memory properties.

The liquid phase chemical enhanced oxidation (LPCEO) technique was applied to achieve planarized isolation of a high-indium-content In0.52Al0.48As/In0.8Ga0.2As metamorphic high-electron-mobility transistor (MHEMT). Through a simple, low-temperature process not requiring costly machinery, electrical isolation of components was accomplished. In addition, multiple advantages were gained, including the production of planarized surfaces, low pollution, and reduction in the subsequent disposal of wet etching solution and costs for dry etching or ion implantation. Because of the decrease in lateral defect density caused by wet or dry etching and the further decrease in gate leakage current owing to the isolated oxide film, the performance of devices, with improved DC characteristics, less flicker noise, and enhanced high-frequency performance, can be increased.

Cellulose nanofibers (CNFs) have received considerable attention as reinforcing fillers due to their excellent and versatile properties, including physical, morphological, and chemical features. Despite many advantages of CNFs, the hydrophilic nature of CNFs significantly limits their use as fillers. In this study, CNFs were modified by esterification with two kinds of carboxylic acids: valeric acid (VA) and hexanoic acid (HA). The degree of substitutions (DS) of VA-CNF and HA-CNF was 2.78 ± 0.04 and 2.61 ± 0.02, respectively. The dispersibility in an isopropanol solvent showed the controlled hydrophilicity of the modified CNFs. Moreover, the water contact angles of VA-CNF and HA-CNF were 79.2 ± 3.1° and 85.0 ± 1.7°, respectively, while the neat CNF was just 18.9 ± 1.6°. The thermogravimetric analysis (TGA) revealed that the modified CNFs have much better thermal stability than the neat CNFs. Also, the CNF films showed uniform-sized nano-porous structures after the modifications of CNFs. Combined with well-improved hydrophobicity, these multi-faceted results suggest that our esterification technique of CNFs can be applied in a wide range of eco-friendly materials applications.

Objective This study hypothesized that the suture anchor of tibial fixation method of PMMR repair technique is the main factor which reduce the gap formation or over displacement of tear site in initial healing, and then investigated the fixation stability of 4 different tibial fixations through cyclic and ultimate failure load testing of meniscal root sutures. Methods Twenty-four porcine tibiae with intact medial meniscus roots were randomly assigned into 4 groups: transosseous suture, washer, suture anchor, or screw with washer. Each sample underwent cyclic loading followed by a load-to-failure test. Displacement, maximum load to failure, stiffness, and elongation at failure load were recorded. Results The maximum average load and displacement at failure for each of the repair groups were as follows: transosseous suture, 232.8 N and 12.16 mm; washer, 189.9 N and 21.5 mm; suture anchor, 140.6 N and 13.8 mm; and screw with washer, 167.9 N and 18.9 mm. The maximum stiffness values for each of the repair groups were as follows: transosseous suture, 19.5 ± 0.7 N/mm; washer, 21.5 ± 1.4 N/mm; suture anchor, 13.8 ± 0.7 N/mm; and screw with washer, 18.9 ± 3.9 N/mm. The mean elongation across the repairs for each of the repair groups after 1000 loading cycles was: transosseous suture, 3.74 ± 0.28 mm; washer, 3.04 ± 0.13 mm; suture anchor, 2.25 ± 0.33 mm; and screw with washer, 2.43 ± 0.19 mm. The mean elongation was significantly less with the suture anchor than with the other techniques (p Conclusion Under physiological loading, our results indicate that a slower rehabilitation program with limited flexion and only partial weight bearing is advised when using a suture anchor because of the lower maximum load and stiffness. The translational potential of this article Tibial fixation using a washer or a screw with a washer is an effective and cost-saving technique when an option is required with high stiffness and low displacement at failure.

In this paper, the multiferroic BeFiO3 monolayer and NiTiO3–BiFeO3 bilayer thin films were fabricated by spin-coating method on the SrRuO3/n+-Si substrate. The structural and ferroelectric properties of multiferroic BeFiO3 monolayer and NiTiO3–BiFeO3 bilayer thin films were investigated. Both multiferroic films showed the typical XRD patterns of the perovskite structure without presence of the second phase. The electrical properties, such as leakage current and remnant polarization, of the NiTiO3–BiFeO3 bilayer film were superior to those of BeFiO3 monolayer film, which those values were 1.94 × 10−4 A/cm2 at electric field of 0.75 MV/cm and 14.05 μC/cm2, respectively. This outcome is due to the NiTiO3–BiFeO3 bilayer film with a high Schottky barrier height as well as a top NiTiO3 layer on the BiFeO3 film inducing the strain-induced polarization rotation and forming the strong domain-wall pinning.

Summary Designing materials that combine surface superhydrophobicity, high surface areas, large and uniform pore sizes, and excellent stability is a very challenging area for synthetic chemists. Here, we demonstrate a bioinspired encapsulation-rearrangement strategy to construct superhydrophobic mesoporous metal-organic framework (MOF) systems by selectively modifying the external surface of an internal lattice-rearranged mesoporous MOF. The surface of a defective MOF with limited porosity named AlTz-53 is initially modified by hydrophobic alkyl chains through click reactions. Subsequently, the internal framework undergoes lattice rearrangement upon solvent desorption, leading to a significantly improved internal porosity and material crystallinity. Functionalizing the surface of AlTz-68 with octadecene (AlTz-68-C18) induces superhydrophobicity with a water contact angle of 173.6°. AlTz-68-C18 also exhibits one of the largest Brunauer-Emmett-Teller (BET) surface areas among all reported superhydrophobic framework materials. Furthermore, we illustrate that both superhydrophobic AlTz-68-C18 and the corresponding modified sponge exhibit excellent performance toward oil/water separation.

Filling pump operation is an important cause of particle formation in therapeutic protein formulations. The goals of the present study were to investigate the impacts of peristaltic filling pump tubing type, pump operating parameters (acceleration and velocity), and formulation on both nanoparticle and microparticle formation in water, placebo, and a 120 mg/mL mAb drug formulation. Microparticles were quantified using flow imaging microscopy and light obscuration, and nanoparticles were counted with nanoparticle tracking analysis. Pumping of all solutions through Pharmed® tubing resulted in much higher particle levels than processing with Accusil™ or Masterflex® tubing. Pump acceleration did not measurably affect particle levels in pumped solutions, but in some cases, a relatively high pumping velocity of 400 rpm enhanced nanoparticle formation. The presence of surfactants reduced pumping-induced particle formation in the mAb solution, and the effects of 4 different surfactants tested were similar. Biophysical properties (secondary and tertiary structure, and thermal stability) of the protein in solution were not altered by pumping. Overall, this study demonstrates that investigations of pumping parameters and formulations using both nanoparticle and microparticle measurement methods are important for understanding pumping-induced particle formation and developing effective control strategies.

Owing to its simple crystal structure, tetragonal FeSe has been considered as a perfect candidate for investigating the interplays among the superconductivity, magnetism and structural phase transition. Previous works had revealed that superconductivity could only be seen in samples with Se deficiency for the otherwise ferromagnetic tetragonal FeSe. In this study, we investigated the effect of vapor transport annealing on the crystalline quality of FeSe films deposited on flexible muscovite (mica) substrates by pulsed laser deposition. The annealing processes were conducted by sealing FeSe powder in tandem with the as-deposited FeSe films in a quartz tube. The FeSe powder was placed at a distance of about 18.5 cm from the FeSe films and the entire sealed quartz tube (about 1.2 cm in diameter) assembly was put into a Lindberg three-zone furnace and maintained a temperature gradient between the two ends of the quartz tube. The results showed that FeSe films successfully grown on flexible mica substrates and the annealing did improve the morphology and crystallinity of the films, however, the films appeared to have more inhomogeneous phases. We suspect that this might be due to uncompleted FeSe phase nucleation in non-optimum condition. The interface between the muscovite substrate and the FeSe films also could be the caused of the formation of other impurity phases, such as FeSe2and Fe3Se4. Consequently, the obtained films exhibited only paramagnetic behaviors, and there was no sign of zero-resistance down to 2 K.

pH Meter is a device used to express the level of acidity or basicity possessed by a substance or solution. Normal pH has a value of 7 while the pH value> 7 indicates that the substance has alkaline properties while the pH value

The main goal of this study was to use state-of-the-art instruments for nanoparticle (nanoparticle tracking analysis and resonant mass measurement) and microparticle counting (flow imaging) to assess the effects of peristaltic filling pump operation on particle formation in formulations of intravenous immunoglobulin. Microparticle levels were also measured with light obscuration. Postpumping agitation was studied as an accelerated degradation method, 3 different commercial peristaltic tubing types were tested, and the effects of formulation pH and inclusion of polysorbate 80 were determined. Overall, the results documented that nanoparticle measurements, as well as microparticle determinations with flow imaging, were essential to gain rigorous insights into impacts of processing and formulation parameters on pumping- and agitation-induced particle formation. In addition, light obscuration was a relatively insensitive method and failed to detect large increases in protein particles caused by pumping and postpumping agitation. Formulation studies showed that the presence of polysorbate 80 or increasing protein colloidal stability with appropriate choice of buffer generally reduced particle formation. The results highlight the need for filling pump assessments in formulation development studies. Combining such assessments with appropriate analytical methods should help assure that particle levels are controlled during filling pump operation and that the highest quality products are manufactured.

Regarding dihydrogen as a clean and renewable energy source, ammonia borane (NH3BH3, AB) was considered as a chemical H2-storage and H2-delivery material due to its high storage capacity of dihydrogen (19.6 wt %) and stability at room temperature. To advance the development of efficient and recyclable catalysts for hydrolytic dehydrogenation of AB with parallel insight into the reaction mechanism, herein, ZIF-67-derived fcc-Co@porous carbon nano/microparticles (cZIF-67_nm/cZIF-67_μm) were explored to promote catalytic dehydrogenation of AB and generation of H2(g). According to kinetic and computational studies, zero-order dependence on the concentration of AB, first-order dependence on the concentration of cZIF-67_nm (or cZIF-67_μm), and a kinetic isotope effect value of 2.45 (or 2.64) for H2O/D2O identify the Co-catalyzed cleavage of the H-OH bond, instead of the H-BH2NH3 bond, as the rate-determining step in the hydrolytic dehydrogenation of AB. Despite the absent evolution of H2(g) in the reaction of cZIF-67 and AB in the organic solvents (i.e., THF or CH3OH) or in the reaction of cZIF-67 and water, Co-mediated activation of AB and formation of a Co-H intermediate were evidenced by theoretical calculation, infrared spectroscopy in combination with an isotope-labeling experiment, and reactivity study toward CO2-to-formate/H2O-to-H2 conversion. Moreover, the computational study discovers a synergistic interaction between AB and the water cluster (H2O)9 on fcc-Co, which shifts the splitting of water into an exergonic process and lowers the thermodynamic barrier for the generation and desorption of H2(g) from the Co-H intermediates. With the kinetic and mechanistic study of ZIF-67-derived Co@porous carbon for catalytic hydrolysis of AB, the spatiotemporal control on the generation of H2(g) for the treatment of inflammatory diseases will be further investigated in the near future.

Light scattering patterns are commonly used in industry to assess fiber quality. In this work, scattering patterns of Bragg fibers are studied. Optical fibers are coated with alternating layers of Silicon Nitride and Silica using Plasma Enhanced Chemical Vapor Deposition. A laser beam incident perpendicular to the fiber axis scatters off creating patterns distinct from that of uncoated fibers which exhibit continuous front lobe. Effect of variation in layer properties, polarization, wavelength and fiber symmetry is observed in the patterns. Anomalous suppression and enhancement in angular scattering pattern is explained through a scattering angle diagram. Features in the pattern are mapped to reflectance of the Bragg stack and it is found that a stopband creates the anomalous features in the scattering.

Epoxy resin with excellent mechanical properties, chemical stability, and corrosion resistance has been widely used in automotive and aerospace industries. A thin film of epoxy deposited on a substrate has great application in adhesive bonding and protective coating. However, the intrinsic brittleness of epoxy with a relatively low fracture toughness limits its applications. In this work, graphene nanoplatelets (GNP) were added to the epoxy resin to enhance its toughness, hardness, and elastic modulus. A series of nanocomposites with different loadings of GNP were fabricated. Ultrasonic sonication in combination with surfactant Triton X-100 were employed to disperse GNP in the epoxy matrix. A nanocomposite film with a thickness of 0.3 mm was deposited on an Al substrate using a spinning coating technology. The hardness and elastic modulus of the nanocomposite film on the Al substrate were experimentally measured by a nanoindentation test. Analytical expression of the mode II interfacial fracture toughness for the nanocomposite film on an Al substrate with an interfacial edge crack was derived utilizing the linear elastic fracture mechanics and Euler’s beam theory. End-notched flexure (ENF) tests were conducted to evaluate the mode II fracture toughness. It was found that the hardness, elastic modulus, and mode II fracture toughness of the nanocomposite film reinforced with 1 wt % of GNP were improved by 71.8%, 63.2%, and 44.4%, respectively, compared with the pure epoxy. The presence of much stiff GNP in the soft epoxy matrix prompts toughening mechanisms such as crack deflection and crack pinning, resulting in the improvements of the fracture toughness, hardness, and elastic modulus. Microscopic observation for the nanocomposite was examined by scanning electron microscopy (SEM) to investigate the dispersion of GNPs in the epoxy matrix. The performance of a nanocomposite film deposited on a substrate was rarely studied, in particular, for the interfacial fracture toughness of the film/substrate composite structure. Utilizing the theoretical model in conjunction with the ENF experimental test presented in this study, an accurate determination of the mode II interfacial fracture toughness of film/substrate composite structure is made possible.

Nanocomposites were prepared by adding graphene nanoplatelets (GNP) into epoxy with a variety of loadings. The thickness of GNPs used in this study was in a range of 1 nm to 10 nm. Nanocomposite film was deposited on the aluminum (Al) substrate via a spinning coating process. Tensile tests were carried out to determine the elastic modulus, ultimate strength and fracture strain of the nanocomposites. Theoretical prediction of the fracture toughness of the film/substrate composite structure with an interfacial crack under mode I loading was derived utilizing linear elastic fracture mechanics theory. Four-point bending tests were performed to evaluate the mode I fracture toughness. It was observed that the performance of the nanocomposite, such as elastic modulus, ultimate strength, and fracture toughness, were significantly enhanced by the incorporation of GNPs and increased with the increase in GNP concentration. The elastic modulus and mode I fracture toughness of the epoxy reinforced with 1 wt.% of GNPs were increased by 42.2% and 32.6%, respectively, in comparison with pure epoxy. Dispersion of GNPs in the epoxy matrix was examined by scanning electron microscope (SEM). It can be seen that GNPs were uniformly dispersed in the epoxy matrix, resulting in the considerable improvements of the ultimate strength and fracture toughness of the nanocomposite.

In this research, an attachable transparent ultrasonic transducer is developed with 86.3% -3dB fractional bandwidth, 6.7MHz center frequency, and 20×20×36mm3 volumetric imaging window which shows the excellent photoacoustic (PA) imaging performance. This transparent transducer is fabricated by depositing 150nm thick Indium tin oxide (ITO) via sputter system on both side of a 110um commercial Polyvinylidene fluoride (PVDF) film in room temperature. Bionic imaging phantoms are made by 3D printer to evaluate the capability of perform PA imaging with skin-like surface, imaging depth, and quality of 3D imaging. A 532nm Nd:YAG laser with 5ns pulse width is penetrated through the ultrasound transducer and excited PA signals when encountered imaging targets. In summary, the competence of achieving in vivo P A blood vessel imaging for wearable healthcare monitoring system using this sensor has been demonstrated.

Summary Despite rapid progress of hybrid organic-inorganic halide perovskite solar cells, using transmission electron microscopy to study their atomic structures has not been possible because of their extreme sensitivity to electron beam irradiation and environmental exposure. Here, we develop cryoelectron microscopy (cryo-EM) protocols to preserve an extremely sensitive perovskite, methylammonium lead iodide (MAPbI3) under various operating conditions for atomic-resolution imaging. We discover the precipitation of lead iodide nanoparticles on MAPbI3 nanowire’s surface after short UV illumination and surface roughening after only 10 s exposure to air, while these effects remain undetected in conventional X-ray diffraction. We establish a definition for critical electron dose and find this value for MAPbI3 at cryogenic condition to be 12 e−/A2 at 1.49 A spatial resolution. Our results highlight the importance of cryo-EM since traditional techniques cannot capture important nanoscale changes in morphology and structure that have important implications for perovskite solar cell stability and performance.

Thermal Shield (TS) in ITER tokamak reduces heat loads from vacuum vessel and cryostat to superconducting magnet structure. Unlike to other components in ITER tokamak, most of TS have slender structure with panel thickness of 20 mm. Due to its structural uniqueness, TS cannot be secured on packing box directly since forces caused by lashing ropes may induce undesirable deformation and structural damage during transportation environment. Therefore, transportation jigs are required to support and fasten TS. In this study, structural design and safety assessment of TS transportation jigs are presented. ‘

The main components of the ITER tokamak are assembled from the nine sub-assemblies of the 40° sectors. During the sub-assembly, the Toroidal Field coils (TFCs) are installed outside of the Vacuum Vessel Thermal Shield (VVTS) by rotation. The clearance between TFCs and VVTS is very narrow, in relation to the cooling tube end points, which are connected to the thermal shield manifolds. The dimensional analysis shows that in-situ bending of the VVTS cooling tube is required instead of pre-bending. This paper describes the development of the in-situ bending tool and its validations. The specialized tool is designed and the in-situ bending procedure is verified by structural analysis and mock-up test.

This paper describes the manufacturing study of ITER Lower Cryostat Thermal Shield (LCTS) cylinder components, which are to be delivered to ITER site. All LCTS cylinder 20 ° sectors will be assembled at the ITER site by the flange joints, which are welded to the shells. Reliability of cooling pipe welding was checked by two inspection methods: endoscopy and vacuum leak test. Pre-assembly of three 20 ° sectors is one of the important step to ensure dimensional tolerance and its process is described in details. Dimensions of the pre-assembled 60 ° sector was measured by a laser tracker. The qualification of silver coating facility was carried out using a simple well-defined plate mock-up. After the facility qualification, silver coating of LCTS cylinder 20 ° sectors had been conducted. Technical efforts to improve the coated surface quality are presented in this paper.

Machine tools may be affected by room temperature, the heat generated by the process, and many other factors. These cause the temperature of the spindle, motor, lead screw, and other parts to rise, and this causes thermal deformation. The main purpose of this study was an exploration of the relationship between the temperature of the spindle and thermal deformation. Measurements were made of the increases in temperature of a CNC lathe spindle, and the related axial displacements involved, at spindle speeds of 1000, 2000, and 3000 rpm. Multiple regression analysis and a general regression neural network were used to establish the relationship between thermal deformation and temperature change individually. The results showed the coefficient of determination of the multiple regression analysis to be 0.9275, while the general regression determined by the neural network was 1. The fitting result of the regression neural network was better than that of multiple regression analysis, and the maximum error was less than 0.1 μm. In addition, this study also used COMSOL simulation analysis software to analyze features of the thermal behavior generated by the spindle structure. A trial and error method was used to adjust the boundary conditions. Results showed that the maximum error in temperature rise determination of simulation and experiment was less than 1 °C.

The recent development of ultrathin anion exchange membranes and optimization of their operating conditions have significantly enhanced the performance of alkaline-membrane fuel cells (AMFCs); however, the effects of the membrane/electrode interface structure on the AMFC performance have not been seriously investigated thus far. Herein, we report on a high-performance AMFC system with a membrane/electrode interface of novel design. Commercially available membranes are modified in the form of well-aligned line arrays of both the anode and cathode sides by means of a solvent-assisted molding technique and sandwich-like assembly of the membrane and polydimethylsiloxane molds. Upon incorporating the patterned membranes into a single-cell system, we observe a significantly enhanced performance of up to ∼35% compared with that of the reference membrane. The enlarged interface area and reduced membrane thickness from the line-patterned membrane/electrode interface result in improved water management, reduced ohmic resistance, and effective utilization of the catalyst. We believe that our findings can significantly contribute further advancements in AMFCs.

In this study, we investigated the average power handling capability (APHC) of silicon-oxy-nitride (SiON) thin-film-coated coplanar waveguide (CPW) interconnections for monolithic microwave integrated circuits (MMICs). SiON thin films were prepared through very-high-frequency plasma-enhanced chemical vapor deposition at 40.68 MHz. Films prepared under various annealing conditions were studied. The microwave characteristics of CPW interconnections were analyzed for fitting to the International Technology Roadmap for Semiconductors. SiON thin films were annealed under a vacuum condition for 60 s at 700 °C, 900 °C and 1100 °C. The use of coated and annealed SiON thin films on the low-resistivity Si substrate effectively improved the substrate resistivity, reduced microwave attenuation at 1100 °C, and enhanced the APHC of CPW interconnections. These results indicate that the proposed method is suitable for application to MMICs.

The concrete mix design affects the quality and performance of the concrete. This study is based on the numerical derivation of the approximate average lubricity of the pellets (LTAavg), the establishment of a simple calculation table, and a case study comparing the ratio of traditional concrete (TC) and four-phase concrete (QBC) in terms of the slump, compressive strength, and durability. The results showed that the lubricant quantity (thickness) of the concrete could reach 15–20 cm of the slump when the proper dose of carboxylic acid superplasticizers was added, regardless of the parcels; the W/CM (quality) reached a value between 0.24 and 0.40 for any kind of concrete, while a lower water-cement ratio or a greater thickness resulted in a higher compressive strength; the strength of traditional concrete with a larger lubricant amount (48.3 μm) was still higher with a value of W/CM = 0.32, but QBC concrete with a high LQTavg value (39.0 μm) had a higher strength at 7 days, while the LQTavg value was lower (

A temperature calibration device is a tool used to measure the accuracy of a temperature-related device such as a sterilisator. This temperature calibration device is needed when the temperature in the sterilisator is not linear. In this calibration tool the sensor used is a type-k thermocouple that is inserted into the media to be measured then the temperature results will be read. This tool is designed using pre-experimental methods with the type of after only design research. In this tool is equipped with storage on the micro sd card and also conversion mode to convert temperature results from Celsius to Rheamur, Farenheit and Kelvin. Temperature results will be displayed on a 4x20 LCD and processed using Arduino UNO. This module can be used in medical equipment calibration laboratories. After testing the thesis module with a comparison device from BPFK, the biggest error is obtained at 1% at 50 ° Celsius, 100 ° Celsius and 150 ° Celsius. The smallest percentage of error is 0% at 50 ° Celsius and 150 ° Celsius. It can be concluded that the tool "Temperature Calibrator (5 Channels) Using Thermocouple Equipped with Data Storage.

In this study, a facile method was developed to fabricate MoS2 nanosheet-enhanced Pebax-MoS2 mixed matrix membranes (MMMs) for CO2 capture. A super mixer was introduced to ensure the homogeneity of the as-prepared solutions, and a far more efficient method of Pebax-MoS2 MMM preparation was accordingly achieved. The membrane structures were observed by SEM, and membrane crystallinity was examined by XRD and DSC. FTIR and Raman spectroscopy were utilized to verify that the Pebax-MoS2 membranes were well prepared. The gas permeability results showed that the Pebax membrane doped with 4.76 wt % MoS2 nanosheets had the best performance, with a CO2 permeability of 67.05 Barrer and CO2/N2 selectivity of 90.61. The molecular simulation technique used for the Pebax-MoS2 MMMs was first adopted by our group to investigate CO2 solubility and CO2/N2 solubility selectivity. The simulation results demonstrated the strong affinity of CO2 for the added MoS2, consequently contributing to high CO2/N2 selectivity, and were highly correlated with the experimental results. Pebax-1657-based MMMs incorporating MoS2 nanosheets can be therefore be considered a promising alternative for CO2 capture applications.

Tissue Processor Tissue Processor consists of consists of several stages of dehydration, clearing, and paraffin infiltration.Phase dehydration to remove water content in tissues by immersion into alcohol. Clearing stage is the process of pulling out the alcohol content in the network by using a liquid xylol. Paraffin infiltration stages is the stage of filling cavities with liquid paraffin tissue. The purpose of this research is to modify the equipment that had broken before became an useful equipment that use basic controlled PLC. This modification tool-making using the "one-group posttest design" by treatment of the instrument without first measuring the initial state, the results of treatment directly measured without comparison to a control group. Making the modification tool using PLC as the main controller throughout the series. The tool mechanical motion using DC motors and AC motors as well as the use of two sensors limit switch as the controller limits the motor movement. Based on the results obtained temperature measurement error with the largest value of 4.44% in paraffin heater tube 1 and the biggest error of 4.0% in paraffin heater tube 2. While the measurement time of each - each tube obtained the smallest error on the tube-to-one by 0 , 03%, and the biggest error of measurement contained in the tube to the fourth, fifth, sixth, eighth and tenth of 0.16%.

Graphene with high electric and thermal conductivities has been widely used as reinforced filler. In this study, graphene loadings in the range between 0.3 and 1.0 wt.% were added to the epoxy to fabricate the nanocomposites. The mechanical and thermal properties of nanocomposites were characterized using tensile test and differential scanning calorimeter (DSC), respectively. Experimental results show that the elastic modulus, yield strength, ultimate strength and glass transition temperature of the graphene reinforced epoxy are increasing with the increase of the graphene, while the fracture strain and toughness are decreasing with the increase of the graphene. Scanning electron microscope (SEM) was employed to investigate the dispersion and separation of graphene in the epoxy based matrix. The SEM images depict that graphene is well dispersed resulting in a significant improvement of the mechanical and thermal properties of the nanocomposites. The mechanical properties and thermal stability of epoxy nanocomposites with graphenes and multi-walled carbon nanotubes additives were then compared. Experimental results show that nanocomposite with graphene additives outperform the multi-walled carbon nanotube additives.

In this letter, a room-temperature synthesized amorphous indium-zinc oxide (InZn x O y ) sensing membrane on flexible polyimide is employed as an extended-gate field-effect transistor (EGFET) pH sensor for the first time. The InZn x O y -based EGFET sensor exhibited a high pH sensitivity of 56.29 mV/pH with an excellent linearity of 0.999. Furthermore, it also demonstrated good stability in terms of a low hysteresis voltage of 4.6 mV and a small drift rate of 2.08 mV/h, presumably suggesting the formation of uniform, dense, small grains, and stoichiometric InZn x O y thin film, which facilitates high conductivity and provides a large number of surface binding sites. The InZn x O y -based EGFET pH sensor showed an excellent mechanical bendability after more than 500 bending cycles.

Titanium (Ti) is a biocompatible alloy widely used in dental implants, thanks to the protective Ti oxide film that forms spontaneously on the surface. Unfortunately, the film is bioinert and prone to the release of metal ions. In a previous study, we applied oxygen plasma immersion ion implantation (O-PIII) treatment to Ti surface to enhance the corrosion resistance and cell response of Ti. In this study, we examined the surface characteristics of the treated alloy, including roughness, hydrophilicity, and chemical composition. We investigated the blood response to the O-PIII-treated Ti surfaces, including the blood-clotting ability and platelet adhesion. We also investigated resistance of the treated alloy to the adhesion of oral bacteria, Streptococcus mutans, in terms of bacterial attachment and morphology. Our results demonstrate that O-PIII treatment did not have a significant effect on surface roughness or hydrophilicity. This treatment resulted in the formation of a Ti oxide film containing mainly TiO2, Ti2O3, and TiO. The presence of surface Ti oxides (particularly TiO2) positively influenced blood-clotting ability and platelet adhesion as well as resistance to bacterial adhesion. These effects were particularly evident when O-PIII treatment was applied at a higher voltage. Our results demonstrate that the proposed O-PIII treatment promotes blood-clotting and resistance to bacterial adhesion in dental implant applications.

Ti-6Al-4V is a biocompatible alloy widely used for dental prostheses. Unfortunately, the oxide film that forms spontaneously on the surface is bioinert and sometimes prone to the release of metal ions. In this study, we applied nitrogen plasma immersion ion implantation (N-PIII) treatment to Ti-6Al-4V in order to improve corrosion resistance and biological responses, including cell growth and antibacterial adhesion, for dental applications. We then analyzed the surface characteristics, such as topography, chemical composition, hardness, and hydrophilicity. Resistance to corrosion was examined using potentiodynamic polarization curves obtained in artificial saliva, simulated body fluid, and simulated blood plasma solutions. Human bone marrow mesenchymal stem cells were used to test cell responses, including adhesion, proliferation, and mineralization. The oral bacteria, Streptococcus salivarius, was used to evaluate antibacterial adhesion, including bacterial attachment and morphology. Our results demonstrate that N-PIII treatment did not significantly affect surface roughness at the macroscopic (micrometer) scale or hydrophilicity. During N-PIII treatment, a thin film of TiN (

In this work, we developed YbTaxOy sensing membranes displaying super-Nernstian pH-sensitivity for use in electrolyte–insulator–semiconductor (EIS) pH sensors. We examined the effect of tantalum content on the structural properties and sensing characteristics of the YbTaxOy sensing membranes deposited through reactive co-sputtering onto Si substrates. X-ray diffraction, atomic force microscopy, secondary ion mass spectrometry, and X-ray photoelectron spectroscopy revealed the structural, morphological, depth, and chemical features, respectively, of these YbTaxOy films prepared under various Ta plasma power conditions (from 80 to 160 W). Among the tested systems, the YbTaxOy EIS device prepared at the 120 W condition exhibited the super-Nernstian sensitivity (70.24 mV/pH), the lowest hysteresis voltage (1.5 mV), and the lowest drift rate (0.26 mV/h). Presumably, this condition optimized the stoichiometry of YbTaO4 in the film and its surface roughness while reducing the crystal defect and suppressing silicate formation at the YbTaxOy–Si interface. The super-Nernstian pH-sensitivity may be attributed to the incorporation of Ta ions in the Yb2O3 forming a YbTaO4 stoichiometric film, enhancing a change in oxidation state of Yb from trivalent ion to bivalent ion and thus transferring one electron to two protons in the redox reaction.

We present a unique way of combining alkali treatment and natural cross-linker, procyanidin, to create submicron-porous structure (pore size 100–300 nm) and immobilize type I collagen on the surface of electron beam melted β-type Ti-24Nb-4Zr-8Sn (Ti2448) alloy scaffold with interconnected porosity. Scanning electron microscopy and transmission electron microscopy showed a hybrid layer, an outer submicron-porous layer and an inner dense layer, was formed on the interconnected Ti2448 alloy scaffold surface. X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and Sirius red staining analysis confirmed the collagen was successfully immobilized on the scaffold. The dense inner oxide layer mainly provided Ti2448 alloy scaffold with enhanced corrosion resistance. The Ti2448 alloy scaffolds, with and without surface treatments, were potentially non-cytotoxic; particularly, the type I collagen-immobilized Ti2448 alloy scaffold via procyanidin cross-linking showed better adhesion of human bone marrow mesenchymal stem cells. The proposed simple and unique surface treatment simultaneously enhances the corrosion resistance and cell adhesion of interconnected porous Ti2448 alloy scaffold without causing cytotoxicity and shows great potential for biomedical implant applications.

Organic light-emitting diodes (OLEDs) hold great promise as low-cost and large-area electro-optical devices. However, it is important to increase their efficiency for display and lighting applications because of the limited light extraction and absorption in conventional device architectures. In this study, we fabricated a biomimetic transparent brightness enhancement layer (BEL) using cicada wings and applied it to OLEDs. The BEL not only reduced the reflection at the interface between air and glass to 1.4% but also enhanced the transmittance to 91.6%. In addition, the light outcoupling of the OLEDs was increased by approximately 22.2% by employing the biomimetic BEL. The light-emission efficiency of the current OLEDs was improved using the bioinspired structure based on cicada wings.

Initial bacterial adhesion on dental implant abutment is related to its surface chemical composition and physical characteristics. Selection of appropriate abutment materials resistant to bacterial adhesion is important for dental implant maintenance. The aim of present study was to evaluate the effect of different properties of abutment materials on initial bacterial adhesion in vitro. Polished zirconia (PZ group), polished titanium (PT group) and ground titanium (GT group) samples were prepared to simulate clinical dental implant abutments. Chemical compositions, morphology, roughness, hydrophilicity and surface free energy of materials were analyzed. Oral commensal bacterium Streptococcus mitis was used to evaluate initial bacterial adhesion via turbidity test and colony-forming unit counting. The results showed that GT group presented the highest roughness, hydrophilicity and surface free energy. After 6-h incubation, GT group showed the significantly highest adhered bacteria counts; while non-significant difference existed between PT and PZ groups. Within the clinically applicable range used in present study, the surface physical characteristics, instead of surface chemical composition, of dental abutment material have the pronounced influence on initial 6-h bacterial adhesion.

Our objective in this study was to evaluate biological responses to a unique multiform nano-network of TiO2 on a titanium (Ti) surface for dental implant applications. A novel multiform TiO2 nano-network was formed on the anodized Ti surface using a simple, rapid electrochemical anodization process. The size of the pores in the nano-network ranged from a few nanometers to a few hundred nanometers. Human bone marrow mesenchymal stem cells (hBMSCs) were used as a model in this study. The multiform nanostructure, which is on the scale of various biological species, was shown to enhance protein adsorption, cell motility, cell proliferation, cell differentiation, and surface bioactivity, as well as stimulate outside-in signals via integrins and the formation of focal adhesion complex. It was also shown to promote hBMSCs toward the osteogenic differentiation pathway and convert the Ti surface from bioinert to bioactive. This is a clear indication that the proposed multilayer TiO2 nano-network has excellent biocompatibility and surface bioactivity. The bioactive TiO2 nano-network structure introduced in this study has considerable potential for applications in implant dentistry.

The corrosion behavior of an Fe70C10P10B5Mo5 amorphous ribbon was investigated in various CO2/CO mixed gases within the oxygen partial pressure range 7.2 × 10−24 to 7.2 × 10−22 Pa at 500 °C. In general, the amorphous alloy exhibited exclusive oxidation throughout the study, and its oxidation kinetics followed the parabolic rate law. The parabolic rate constants steadily increased with increasing oxygen pressure, indicating a typical scaling behavior for p-type semiconductivity. The scale formed on the glassy alloy consisted mostly of Fe3O4 and a minor amount of B2O3, and the formation of B2O3 is responsible for the lower scaling rate of the glassy alloy as compared with that of pure Fe.

The initial corrosion behavior of pure zinc during 168 h of immersion in Hanks’ solution, simulated body fluid (SBF), Dulbecco’s modified Eagles’ medium (DMEM), and DMEM with 10% fetal bovine serum (FBS) was investigated. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization were performed on samples after immersion. The morphology and chemical composition of corrosion products were determined by environment scanning electron microscope, x-ray diffraction, x-ray photoelectron spectroscopy, and Fourier transform infrared spectrometer. The results demonstrated that pure Zn degraded at a rate of 0.01 mm yr−1 to 0.02 mm yr−1 in DMEM and DMEM + FBS and exhibited the highest corrosion rate in SBF. It was shown that the composition of solution was crucial for the evaluation of degradation behavior in vitro. Insoluble salts formation and organic components in DMEM retarded the degradation of Zn. The presence of proteins increased the polarization resistance while it also exacerbated localized corrosion.

Paper-basedpentacene organic thin-film transistors (OTFTs) with spin-coated gelatin (G) stacked gate dielectric layers, the Au/pentacene/G/G matrix-embedded iron (FeG)/Al/paper structure, were fabricated. The proposed composite-stacked bio-dielectric layer can be implemented using solutions with the degradable biomaterials. These materials enable a large-area printing of use-and-throw devices. Control devices (Au/pentacene/G/Al and Au/pentacene/FeG/Al structure) were also fabricated for comparison. High-performance paper-based OTFT constructed from the stacked gate dielectric layer exhibited a carrier mobility of 8 cm2/Vs, an ON/OFF current ratio of approximately 103, a subthreshold swing of 0.6 V/decade, and a threshold voltage of −1.4 V. These results are compatible to those OTFTs fabricated on other substrates. Therefore, the emerging biomaterial-based transistors on paper substrates may help in developing low-cost, environment-friendly devices.

“Green’’ electronics represents an emerging area of research aimed at identifying natural materials that are applicable for environmentally safe and biodegradable devices. Iron (Fe) ions are used in gelatin matrixes (gelatin composites) prepared on commercially available flexible paper substrates through the solution method, thus, the “green” electronics were achieved. Although atomic force microscopy images show that fiber-based paper substrates result in rough Al/paper structure surfaces, the uniform interface between top Al electrodes and gelatin composites can be clearly observed in transmission electron microscopy images. This might be due to the gelatin composite acts as not only the resistive layer, but also the smoothing layer. Moreover, Fe ions play an important role in assisting redox reaction or filament formation. An Al/gelatin/Al/paper device has no resistive switching behavior. Meanwhile, devices with Fe ions on a paper substrate show reproducible resistive switching for 18 cycles, an ON/OFF ratio of over 105, and an excellent current distribution (coefficient of variation

The development of efficient and low energy-consumption catalysts for CO2 conversion is desired, yet remains a great challenge. Herein, a class of novel hollow porous carbons (HPC), featuring well dispersed dopants of nitrogen and single Zn atoms, have been fabricated, based on the templated growth of a hollow metal-organic framework precursor, followed by pyrolysis. The optimized HPC-800 achieves efficient catalytic CO2 cycloaddition with epoxides, under light irradiation, at ambient temperature, by taking advantage of an ultrahigh loading of (11.3 wt %) single-atom Zn and uniform N active sites, high-efficiency photothermal conversion as well as the hierarchical pores in the carbon shell. As far as we know, this is the first report on the integration of the photothermal effect of carbon-based materials with single metal atoms for catalytic CO2 fixation.

The role of the ITER Tokamak thermal shield system is to minimize heat loads transferred from the hot tokamak components to the cooled superconducting components. The system consists of two single wall structures fabricated from 304L-(N) stainless steel. Both structures are actively cooled with pipes permanently welded to the structure and filled with pressurized helium gas at 80K. One structure is the Vacuum Vessel Thermal Shield (VVTS), which protects magnet components from Vacuum Vessel (VV) radiation. The second structure is the Cryostat Thermal Shield (CTS), which protects magnet components from in-Cryostat components’ radiations such as the Cryostat (at 293K), the VV Ports (at 393K), and the water cooling system (at 350K). In 2012, thermal analyses were performed in order to verify the thermal integrity of the ITER CTS 2010 baseline design. The heat loads to the CTS were estimated according to load specification as a homogeneous distribution based on cryostat temperature at 293K. Following this study, in order to determine a more realistic heat load distribution on the CTS panels, we performed a detailed 3D analysis of the Cryostat-CTS interspace. This paper describes the methodology used, based on view factors combined with Kirchhoff's law, to define the heat flux deposition on the CTS from its surrounding components via radiation. The previous thermo-hydraulic analysis models have been adapted using this method to define the temperature distribution and total power transmitted to the magnets. Despite an increase of 30% of the CTS total power deposition on the superconducting components in comparison to the previous analysis, we found the total heat power deposition onto the superconducting components at 4K to be within the limit of the design requirement (P≤1900W).

In this study, we present the new transparent coplanar waveguide (CPW) bandpass filter using aluminum (Al) thin film micromesh structure. The filter is prepared by the semiconductor process of dc sputtering and standard lift-off technology. In order to achieve the high-performance transparent bandpass filter, the new aluminum thin film micromesh structure with low resistivity to 10-8Ω-cm, uniform Al thin film thickness to 3μm, high optical transparent to 78% and simple manufacturing process has been proposed. The transparent bandpass filter is designed at 2.4 GHz with 3-dB fractional bandwidth (FBW) of 5%, the minimum insertion loss (-20 log |S21|) of 1.8 dB and the return losses (-20 log |S11|) of 25 dB. The simulated and measured results of the transparent bandpass filter are in good agreement. The proposed transparent bandpass filter is showing a simple coplanar waveguide configuration, low thin film resistivity, high thin film transmittance, high filter performance, and small circuit size.

A strategy for fabricating zirconium oxide doped nanoporous carbons derived from metal-organic gels (MOGs) is reported. For the first time, the achievement of metastable ZrO2-NPCs is demonstrated. The direct pyrolysis of MOGs provided new perspective in developing metal oxide-doped NPCs and circumvented the shortcomings of existing methods in synthesizing metastable ZrO2 doped NPCs.