Polymeric binders that can undergo slurry fabrication and minimize the disruption of interfacial Li+ contact are imperative for sheet‐type electrodes and solid electrolyte films in practical ...all‐solid‐state Li batteries (ASLBs). Although dry polymer electrolytes (DPEs) are a plausible alternative, their use is complicated by the severe reactivity of sulfide solid electrolytes and the need to dissolve Li salts. In this study, a new scalable fabrication protocol for a Li+‐conductive DPE‐type binder, nitrile‐butadiene rubber (NBR)‐LiTFSI, is reported. The less‐polar dibromomethane and more‐polar hexyl butyrate in cosolvents work synergistically to dissolve NBR and LiTFSI, while preserving Li6PS5Cl0.5Br0.5. It is found that the dispersion of NBR can be controlled by the fraction of the antisolvent (hexyl butyrate), which in turn affects the corresponding performance of the ASLBs. Sheet‐type LiNi0.70Co0.15Mn0.15O2 electrodes tailored using NBR‐LiTFSI outperform those prepared using the conventional insulating binder (NBR) in terms of capacity (163 vs 147 mA h g−1) and initial Coulombic efficiency (78.9 vs 70.4%), which is attributed to the facilitated interfacial Li+ transport, as confirmed by 6Li nuclear magnetic resonance and electrochemical measurements. Moreover, NBR‐LiTFSI is functional at 70 °C and in a graphite anode. Finally, the promising performance of pouch‐type LiNi0.70Co0.15Mn0.15O2/graphite ASLBs is also demonstrated.
A new scalable slurry fabrication protocol using a cosolvent targeting dry polymer electrolyte (DPE)‐based binders for all‐solid‐state batteries is developed. Binder dispersion is controlled by adjusting the ratios in the cosolvent, affecting the electrochemical performance. LiNii0.70Co0.15Mn0.15O2 and graphite electrodes tailored from slurries using cosolvents of dibromomethane and hexyl butyrate, targeting the accommodation of DPE and Li6PS5Cl0.5Br0.5, exhibit significantly improved performance.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Lead‐free piezoelectric ceramics, 0.96{Bi0.5 (Na0.84K0.16)0.5}1−xLix(Ti1−yNby)O3–0.04SrTiO3 (BNKLiTN–ST) with x, y = 0–0.030, were synthesized by solid‐state reaction method. X‐ray diffraction ...patterns indicated that Li and Nb successfully diffused into the BNKT–ST lattice and formed a pure perovskite structure with x, y ≤ 0.025. Increasing the Li and Nb contents (x, y = 0.020) induced a phase transformation from the coexistent rhombohedral–tetragonal phases for pure BNKT–ST ceramics to a pseudocubic phase, resulting in degradation of the remnant polarization and coercive field. However, the field‐induced strain was markedly enhanced at x, y = 0.020, giving rise to a giant dynamic piezoelectric constant (d33* = Smax/Emax = 800 pm/V). Furthermore, the temperature dependence of the field‐induced strain response showed temperature‐insensitivity up to 120°C. To explore its potential for device applications, a 10‐layered stack‐type multilayer actuator was fabricated from the optimal composition (x, y = 0.020). This actuator showed a large Smax/Emax of 600 pm/V at a relatively low driving field of 4.5 kV/mm suggesting highly promising results in lead‐free BNT‐based ceramics.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
The tunable photoluminescence of carbon‐based nanomaterials has received much attention for a wide range of applications. Herein, a unique, broad‐solvatochromic hybrid carbon nanosheet (CNS) ...synthesized through the hydrothermal carbonization of molecular precursors exploiting graphene oxide as a template is reported, resulting in the formation of clusters of carbon nanorings on the surface of graphene‐oxide nanosheets. Under UV and visible‐light excitation, the hybrid CNS exhibits tunable emission spanning the wide range of colors in a series of solvents with different polarities. This interesting spectroscopic behavior is found to originate from hydrogen‐bonding interactions between CNS and solvents, which eventually induce the morphological transition of CNS from 2D sheets to 3D crumpled morphologies, affecting the lifetimes of emissive states. This novel soft carbon nanostructure may open up a new possibility in tailoring the photophysical properties of carbon nanomaterials.
Solvatochromic hybrid carbon nanosheets (CNSs) exhibit highly tunable emission spanning the wide range of colors in a series of solvents with different polarities. The solvatochromic behavior of CNS originates from morphological transition from 2D nanosheet to 3D crumpled structure of CNS, due to the different degrees of the exposure of surface functional groups to the solvent and the solute–solvent hydrogen‐bonding interactions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Mechanochemical syntheses of rotaxanes have attracted considerable attention of late because of the superior reaction rates and higher yields associated with their production compared with analogous ...reactions carried out in solution. Previous investigators, however, have focused on the demonstration of the mechanochemical syntheses of rotaxanes per se, rather than on studying the solid-phase host–guest molecular interplay related to their rapid formation and high yields. In this investigation, we attribute the lower yields of rotaxanes prepared in solution to the limited concentration and a desolvation energy penalty that must be compensated for by host–guest interactions during complexation that precedes the templation leading to rotaxane formation. It follows that, if the desolvation energy can be removed and higher concentrations can be attained, even weak host–guest interactions can drive the complexation of host and guest molecules efficiently. In order to test this hypothesis, we chose two host–guest pairs of permethylated pillar5arene/1,6-diaminohexane and permethylated pillar5arene/2,2′-(ethylenedioxy)bis(ethylamine) for the simple reason that they exhibit extremely low binding constants (2.7 ± 0.4 M–1 when 1,6-diaminohexane is the guest and <0.1 M–1 when 2,2′-(ethylenedioxy)bis(ethylamine) is the guest in CDCl3; i.e., ostensibly no pseudorotaxane formation is observed). We argue that the amount of pseudorotaxanes formed in the solid state is responsive to mechanical treatments or otherwise and changes in temperature during stoppering reactions. Compared to the amount of pseudorotaxanes that can be obtained in solution, large quantities of pseudorotaxanes are formed in the solid state because of concentration and desolvation effects. This mechanochemical enhancement of pseudorotaxane formation is referred to as a self-correction in the current investigation. Rotaxanes based on permethylated pillar5arene/1,6-diaminohexane and permethylated pillar5arene/2,2′-(ethylenedioxy)bis(ethylamine) have been synthesized in much higher yields compared to those obtained in solution, aided and abetted by self-correction effects during mechanical treatments and heating at a mild temperature of 50 °C.
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IJS, KILJ, NUK, PNG, UL, UM
Inkjet-printed electronics using metal particles typically lack electrical conductivity and interfacial adhesion with an underlying substrate. To address the inherent issues of printed materials, ...this Research Article introduces advanced materials and processing methodologies. Enhanced adhesion of the inkjet-printed copper (Cu) on a flexible polyimide film is achieved by using a new surface modification technique, a nanostructured self-assembled monolayer (SAM) of (3-mercaptopropyl)trimethoxysilane. A standardized adhesion test reveals the superior adhesion strength (1192.27 N/m) of printed Cu on the polymer film, while maintaining extreme mechanical flexibility proven by 100 000 bending cycles. In addition to the increased adhesion, the nanostructured SAM treatment on printed Cu prevents formation of native oxide layers. The combination of the newly synthesized Cu ink and associated sintering technique with an intense pulsed ultraviolet and visible light absorption enables ultrahigh conductivity of printed Cu (2.3 × 10–6 Ω·cm), which is the highest electrical conductivity reported to date. The comprehensive materials engineering technologies offer highly reliable printing of Cu patterns for immediate use in wearable flexible hybrid electronics. In vivo demonstration of printed, skin-conformal Cu electrodes indicates a very low skin-electrode impedance (<50 kΩ) without a conductive gel and successfully measures three types of biopotentials, including electrocardiograms, electromyograms, and electrooculograms.
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IJS, KILJ, NUK, PNG, UL, UM
Hard piezoelectric properties are investigated in lead‐free BiFeO3–BaTiO3 (BF–BT) ceramics. Rhombohedral (R) phase ceramics of (1 – x)BF–xBT (x = 0.20–0.30) were prepared using a conventional ...solid‐state reaction and water‐quenching process. The R structure is observed in x = 0.20–0.275, and the R and tetragonal phases coexist at x = 0.30. The piezoelectric charge sensor coefficient (d33) and electromechanical planar coupling factor (kp) increase with increasing BT content, whereas the mechanical quality factor (Qm) decreases. The x = 0.20 ceramic shows the best hard piezoelectric properties: the highest Qm = 403 and the highest TC = 607°C. In contrast, x = 0.30 ceramic shows soft piezoelectric properties: d33 = 301 pC/N and kp = 0.33 with TC = 510°C. These results show that the BF–BT system in R‐phase‐rich region has good hard piezoelectric properties for transducer applications.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In the architectural design process, the conceptual design stage is to devise a creative alternative in response to the intent of the architects. In this paper, we propose an alternative ...evolutionary-based architectural design method by using the Implicit Redundant Representation Genetic Algorithm (IRRGA) that is highly suited to explore unstructured problem formulation such as conceptual design. Also, a new string representation for apartment building designs is proposed such that the size and the number of apartment units with stairs are not fixed and can be changed during the design evolution. The design objectives are selectively applied in terms of symmetry, structure, circulation, and façade. Each objective is used respectively as a fitness function to demonstrate the performance of IRRGA. Finally, a multi-objective fitness function is applied and the resulting apartment building designs show their own level of creativity.
•We propose an evolution-based method for generating conceptual apartment designs.•Implicit Redundant Representation Genetic Algorithm (IRRGA) uses a redundant segment of the string.•A new string representation allows greater flexibility from a simple base unit.•The design objectives include symmetry, structure, circulation, and façade.•The current work applies IRRGA to generate creative apartment building designs.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•We present a CNN-based filtering method to detect acoustic emission crack signals.•Laboratory-trained models effectively capture crack signals in upscaled conditions.•The presented technique can be ...used for real-time SHM of piled raft foundations.
Acoustic emission (AE) monitoring has gained significant interest as a promising method for monitoring of changes in structural integrity and durability. Long-term AE monitoring needs to detect and distinguish crack signals from ambient noise (or dummy) signals; however, it is still a daunting task which currently limits field implementation of the AE method. Herein, we explore the feasibility of using convolutional neural network (CNN) models to detect AE crack signals from ambient signals. The trained models are validated both with noise-embedded synthesized signals and with upscaled physical model experiments simulating earthquake loading to a scaled model foundation by using a large-scale shaking table. The 2D CNN model trained the laboratory-synthesized signal sets effectively captured the crack and crack-free signals in all cases including the upscaled physical model experiments. This study presents a simple but robust CNN model for pre-filtering of crack signals and a novel training method for enhanced accuracy, which can be applied for real-time structural health monitoring of concrete-based structures.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this article, structure, dielectric, ferroelectric and piezoelectric properties of Bi rich Bi1.05(Zn0.5Ti0.5)O3-modified BiFeO3-BaTiO3 (BF-BT-xBZT) ceramics were investigated experimentally. ...Crystal structure, phase purity and microstructure were examined through X-ray diffractometry and scanning electron microscopy, respectively. The crystallographic results show the formation of single-phase solid solutions for all compositions except x = 10 mol%. The BF-BT modification through BZT instigates variation in grain size, enhancement in Curie temperature (TC) and field induced polarization and strain response. Large field induced strain of ∼0.24% at low driving field along with a small hysteresis of ∼38% was observed for 2 mol% BZT modified BF-BT ceramics. These investigated results signpost the potentiality of BF-BT-xBZT ceramics in high temperature piezoelectric device applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Soils affected by animal wastes have simultaneously high N and P contents. Despite the reports of high nitrous oxide (N
2
O) emissions in such environments, the role that P plays in N
2
O dynamics ...has not yet been systematically investigated. Here, we report the enhancement effect of orthophosphate (PO
4
3−
-P) abundance on N
2
O yields from abiotic NH
2
OH decomposition, which may have substantial implications to N
2
O emissions from nitrification in such P-rich soils. The axenic cultures of
Nitrosomonas europaea
, an ammonia-oxidizing bacterium previously reported to leak NH
2
OH, exhibited significantly higher N
2
O yields when incubated at higher PO
4
3−
-P concentrations. As NH
4
+
-to-NO
2
−
turnover and growth rates were unaffected even at the highest PO
4
3−
-P concentration examined, the abiotic interaction between extracellularly released NH
2
OH and PO
4
3−
-P was the most plausible mechanism of enhanced N
2
O emission in these nitrifier cultures. This proposed mechanism was supported by the results of abiotic NH
2
OH incubation whereby higher PO
4
3−
-P concentration resulted in higher N
2
O yield. Orthophosphate enhancement of NH
2
OH-to-N
2
O turnover was then simulated with addition of 5 μmol NH
2
OH to an ornithogenic soil with high PO
4
3−
-P content (23.9 ± 6.7 g/kg wet soil) and active nitrification activity after sterilization. The N
2
O yield, 69.0 ± 4.6%, was significantly higher than the N
2
O yields for other examined soils with lower PO
4
3−
-P contents (0–1.94 g/kg wet soil), and the PO
4
3−
-P contents of the examined soils exhibited strong correlation with the N
2
O yields. These findings suggest that N
2
O production from nitrification via abiotic turnover of released NH
2
OH may be a consequential mechanism of N
2
O emissions in PO
4
3−
-P-rich soils.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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