The development of methods for the 3D printing of multifunctional devices could impact areas ranging from wearable electronics and energy harvesting devices to smart prosthetics and human–machine ...interfaces. Recently, the development of stretchable electronic devices has accelerated, concomitant with advances in functional materials and fabrication processes. In particular, novel strategies have been developed to enable the intimate biointegration of wearable electronic devices with human skin in ways that bypass the mechanical and thermal restrictions of traditional microfabrication technologies. Here, a multimaterial, multiscale, and multifunctional 3D printing approach is employed to fabricate 3D tactile sensors under ambient conditions conformally onto freeform surfaces. The customized sensor is demonstrated with the capabilities of detecting and differentiating human movements, including pulse monitoring and finger motions. The custom 3D printing of functional materials and devices opens new routes for the biointegration of various sensors in wearable electronics systems, and toward advanced bionic skin applications.
A multifunctional three‐dimensional (3D) printing approach is employed to fabricate 3D tactile sensors under ambient conditions conformally onto freeform surfaces. The sensors can detect and differente human motions, including pulse monitoring and finger movements. This custom 3D printing of functional materials and devices opens new routes toward the biointegration of various sensors in wearable electronic systems.
•The optimum coffee-making process with reduced furan and 5-HMF was prepared.•The range of furan and 5-HMF in samples were 5–362 ppb and 51–1143 ppm.•Furan levels were higher in Arabica than Robusta ...coffees.•Furan increased with increasing roasting temperature/time and in cold-brew.•5-HMF concentration was highest in Robusta coffee and espresso extracts.
Furan and 5-hydroxymethylfurfural (5-HMF) were quantified in 108 coffee models prepared considering the species/origin of the coffee beans, roasting temperature/time, mesh size used to sieve the ground coffee beans, type of extraction water and extraction method. The effect of drinking conditions, such as adding sugar or cream, on furan and 5-HMF levels, was also studied. The range of furan and 5-HMF in coffee samples were 5–362 ppb and 51–1143 ppm, respectively. Furan levels were increased by 198–560% with increasing roasting temperature/time and by 106–399% in cold-brew extracts compared with espresso extracts. Among the mesh sizes used, 500 μm with espresso extraction, and 710 μm with cold-brew extraction led to maximal furan levels. 5-HMF concentration was highest in Robusta coffee and espresso extracts, and decreased by 17–76% with increasing roasting temperature/time. In a drinking condition study, furan level was remained unchanged, even when sugar or cream were added.
Glacial cycles redistribute water between oceans and continents, causing pressure changes in the upper mantle, with consequences for the melting of Earth's interior. Using Plio-Pleistocene sea-level ...variations as a forcing function, theoretical models of mid-ocean ridge dynamics that include melt transport predict temporal variations in crustal thickness of hundreds of meters. New bathymetry from the Australian-Antarctic ridge shows statistically significant spectral energy near the Milankovitch periods of 23, 41, and 100 thousand years, which is consistent with model predictions. These results suggest that abyssal hills, one of the most common bathymétrie features on Earth, record the magmatic response to changes in sea level. The models and data support a link between glacial cycles at the surface and mantle melting at depth, recorded in the bathymétrie fabric of the sea floor.
3D Printed Polymer Photodetectors Park, Sung Hyun; Su, Ruitao; Jeong, Jaewoo ...
Advanced materials (Weinheim),
08/2018, Letnik:
30, Številka:
40
Journal Article
Recenzirano
Odprti dostop
Extrusion‐based 3D printing, an emerging technology, has been previously used in the comprehensive fabrication of light‐emitting diodes using various functional inks, without cleanrooms or ...conventional microfabrication techniques. Here, polymer‐based photodetectors exhibiting high performance are fully 3D printed and thoroughly characterized. A semiconducting polymer ink is printed and optimized for the active layer of the photodetector, achieving an external quantum efficiency of 25.3%, which is comparable to that of microfabricated counterparts and yet created solely via a one‐pot custom built 3D‐printing tool housed under ambient conditions. The devices are integrated into image sensing arrays with high sensitivity and wide field of view, by 3D printing interconnected photodetectors directly on flexible substrates and hemispherical surfaces. This approach is further extended to create integrated multifunctional devices consisting of optically coupled photodetectors and light‐emitting diodes, demonstrating for the first time the multifunctional integration of multiple semiconducting device types which are fully 3D printed on a single platform. The 3D‐printed optoelectronic devices are made without conventional microfabrication facilities, allowing for flexibility in the design and manufacturing of next‐generation wearable and 3D‐structured optoelectronics, and validating the potential of 3D printing to achieve high‐performance integrated active electronic materials and devices.
Fully 3D‐printed polymer photodetectors are demonstrated on flexible substrates and hemispherical surfaces to integrate multidimensional image sensing arrays with high sensitivity and wide field of view. 3D printing multifunctional optoelectronic devices on a single platform is possible from a one‐pot, custom‐built extrusion‐based 3D manufacturing system. This work opens the possibility of the “off‐grid” printing of next‐generation wearable optoelectronic devices.
Biocatalytic cyclization is highly desirable for efficient synthesis of biologically derived chemical substances, such as the commodity chemicals ε-caprolactam and δ-valerolactam. To identify ...biocatalysts in lactam biosynthesis, we develop a caprolactam-detecting genetic enzyme screening system (CL-GESS). The Alcaligenes faecalis regulatory protein NitR is adopted for the highly specific detection of lactam compounds against lactam biosynthetic intermediates. We further systematically optimize the genetic components of the CL-GESS to enhance sensitivity, achieving 10-fold improvement. Using this highly sensitive GESS, we screen marine metagenomes and find an enzyme that cyclizes ω-amino fatty acids to lactam. Moreover, we determine the X-ray crystal structure and catalytic residues based on mutational analysis of the cyclase. The cyclase is also used as a helper enzyme to sense intracellular ω-amino fatty acids. We expect this simple and accurate biosensor to have wide-ranging applications in rapid screening of new lactam-synthesizing enzymes and metabolic engineering for lactam bio-production.
The Australian‐Antarctic Ridge (AAR) is an intermediate‐spreading rate system located between the Southeast Indian Ridge and Macquarie Triple Junction of the Australian‐Antarctic‐Pacific plates. KR1 ...is the easternmost and longest AAR segment and exhibits unique axial morphology and various volcanic structures. We identified three asymmetric seamount chains positioned parallel to the seafloor spreading direction, which were indicative of prevalent off‐axis volcanism in the vicinity of segment KR1. Two‐dimensional magnetic modeling was used to predict the magnetization polarity of the seamounts, as well as to constrain their formation time and duration. The magnetic modeling revealed that the majority of the examined seamounts were formed over a period of less than ∼600 kyrs. The seamount formation primarily occurred during two distinct volcanic pulses from 0.16–1.14 to 1.58–2.69 Ma. A temporal gap of 200–650 kyrs between the formation time of the seamounts and seafloor was estimated for certain seamounts that were formed much later than their underlying seafloor and at a distance of 10–20 km from the KR1 axis. Typically, such off‐axis seamount activity is related to axial mantle convection caused by excessive magma supply near the ridge crest. Considering the scale of off‐axis volcanism and thickening lithosphere ∼20 km away from the axis with intermediate‐spreading rates, small‐scale upwelling made feasible by the fertile mantle heterogeneity is proposed as the mechanism for the seamount formations at off‐axis distances, and the geochemically enriched compositions of the seamounts support this alternative explanation.
Plain Language Summary
The easternmost spreading center of the Australian‐Antarctic Ridge is a plate boundary between the Australian and Antarctic plates, with a large number of underwater volcanoes. The formation time and duration of the underwater volcanic activities were estimated using high‐resolution shipboard magnetic data. Some underwater volcanoes appear to have been formed at a considerable distance from the spreading center, which implies the presence of an excessive magma supply. Our analysis on the temporal gap between the underwater volcanoes and their underlying seafloor formations indicated that these volcanoes originated from a non‐uniform source of upper mantle.
Key Points
Off‐axis seamounts in segment KR1 of the little‐explored Australian‐Antarctic Ridge mostly formed within 3 Myrs based on magnetic data
Simple 2‐D magnetic modeling was effective for constraining the off‐axis seamount formation period
Several seamounts formed later than the underlying seafloor were indicative of an extra melting supply in the KR1 region
Memory metamaterials are artificial media that sustain transformed electromagnetic properties without persistent external stimuli. Previous memory metamaterials were realized with phase-change ...materials, such as vanadium dioxide or chalcogenide glasses, which exhibit memory behaviour with respect to electrically/optically induced thermal stimuli. However, they require a thermally isolated environment for longer retention or strong optical pump for phase-change. Here we demonstrate electrically programmable nonvolatile memory metadevices realised by the hybridization of graphene, a ferroelectric and meta-atoms/meta-molecules, and extend the concept further to establish reconfigurable logic-gate metadevices. For a memory metadevice having a single electrical input, amplitude, phase and even the polarization multi-states were clearly distinguishable with a retention time of over 10 years at room temperature. Furthermore, logic-gate functionalities were demonstrated with reconfigurable logic-gate metadevices having two electrical inputs, with each connected to separate ferroelectric layers that act as the multi-level controller for the doping level of the sandwiched graphene layer.
We fabricate high-performance, flexible, transparent electrochromic (EC) films and thin film heaters (TFHs) on an ITO/Cu/ITO (ICI) multilayer electrode prepared by continuous roll-to-roll (RTR) ...sputtering of ITO and Cu targets. The RTR-sputtered ICI multilayer on a 700 mm wide PET substrate at room temperature exhibits a sheet resistance of 11.8 Ω/square and optical transmittance of 73.9%, which are acceptable for the fabrication of flexible and transparent EC films and TFHs. The effect of the Cu interlayer thickness on the electrical and optical properties of the ICI multilayer was investigated in detail. The bending and cycling fatigue tests demonstrate that the RTR-sputtered ICI multilayer was more flexible than a single ITO film because of high strain failure of the Cu interlayer. The flexible and transparent EC films and TFHs fabricated on the ICI electrode show better performances than reference EC films and TFHs with a single ITO electrode. Therefore, the RTR-sputtered ICI multilayer is the best substitute for the conventional ITO film electrode in order to realize flexible, transparent, cost-effective and large-area EC devices and TFHs that can be used as flexible and smart windows.
The Fourth Industrial Revolution is coming, and it is changing almost all aspects of human life, including the culture of quality and quality management (QM) in industry. This paper first examines ...the essence of the Fourth Industrial Revolution and its impact on our lives. Next, new concepts of quality as well as QM are discussed as follows. First, we analyse the multiway flow of QM in the stages of plan - design - production - marketing - sales, and data-oriented multiway interactions for creating new value and quality are discussed. Second, four distinctive approaches are introduced for implementing the multiway flow in real-world applications. The four approaches, which utilise Big Data, Artificial Intelligence (AI), Internet of Things (IoT), and more, are composite dimension, team creativity, total inspection, and new valuation. Finally, we argue for the necessity of combining quality experts with data scientists to prepare well for the coming Fourth Industrial Revolution.
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