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One of the main challenges with implantable biomedical devices is the replacement surgeries of depleted batteries for elderly patients. This not only poses medical risks but also results in financial burdens. Consequently, there is a growing need for self-powered in vivo electronics that can convert the biomechanical movements of organs into usable electric energy. Notably, a previously reported in vivo flexible energy harvester generated relatively low current output from a living porcine heart, restricting its ability to operate self-powered electronic devices. In this study, a high current output implantable flexible energy harvester was demonstrated by adopting a highly-piezoelectric single crystal Pb(In 1/2 Nb 1/2)O 3 –Pb(Mg 1/3 Nb 2/3)O 3 –PbTiO 3 (PIN–PMN–PT) film. The in vivo flexible energy harvester generated a short-circuit output current of 20 µA (corresponding to a current density of 3.08 µA/mm3) from the contraction and relaxation of a porcine heart. This recorded in vivo output current density was attributed to its outstanding piezoelectric charge coefficient of the single crystal PIN-PMN-PT, optimized Ni stressor assisted exfoliation as well as the implementation of a metal-insulator-metal (MIM) structure. Moreover, the flexible energy harvester was also demonstrated as a self-powered cardiac sensor to monitor irregular heartbeats by observing heart rate variations due to drug administration in a porcine heart. Additionally, output performance evaluation was conducted with the chest closed to further assess the feasibility of practical in vivo harvesting. Finally, the single crystal harvester exhibited biocompatibility, showing no signs of cytotoxicity based on cell viability assessments and histological characterizations. These results underscore the potential of the flexible PIN-PMN-PT energy harvesting device as a sustainable power source for self-powered in vivo biomedical electronics. [Display omitted] • A high current output implantable energy harvester demonstrated in vivo energy harvesting in a large animal model. • The harvester generated a short-circuit current of 20 µA (Current density of 3.08 µA/mm3) from cardiac motion. • The self-powered device exhibits its potential for use as an arrhythmia monitoring cardiac sensor. • The single crystal harvester successfully generate energy from periodic cardiac movement even after surgical suturing. [ABSTRACT FROM AUTHOR]

Abstract An environmentally-friendly lead-free methylammonium tin iodide (MASnI 3) perovskite is successfully synthesized using a facile approach of an antisolvent-assisted collision technique (ACT) under room ambient conditions, which results stability within 24 h under ambient room conditions. The phase transition of MASnI 3 from tetragonal to cubic is first observed at ~ 30 °C. Polycrystalline MASnI 3 films reveal a high dielectric constant of ~ 65 at 100 kHz, a low-leakage current density of 7 × 10−7 A cm−2 at 50 kV cm−1, well-developed P-E hysteresis loops, and a high piezoelectric coefficient (d 33) of 20.8 pm V−1. The MASnI 3 piezoelectric nanogenerator (PENG) shows an output voltage of ~ 3.8 V and an output current density of 0.35 μA cm−2. To enhance the piezoelectric output performance, the MASnI 3 films are composited with an environmentally friendly PVDF polymer that had a porous structure. The PVDF-MASnI 3 composite based-PENG reveals a maximum output voltage of ~ 12.0 V and current density of ~ 4.0 μA cm−2. A green light-emitting diode (LED) using the PVDF-MASnI 3 PENGs is instantly lighted without need of a storage device, and long-term stability of the composite PENGs is validated for 90 days. This simple and cost-effective solution process is feasible for the fabrication of large-scale, high-performance, and environmental-friendly PENGs based on lead-free organic-inorganic perovskites to extensively implicate in medical and biomechanical applications. Graphical abstract An eco‐friendly lead-free MASnI 3 perovskite was synthesized using a facile approach of an antisolvent-assisted collision technique (ACT) under air ambient. Dielectric constant and piezoelectric coefficient of MASnI 3 films were investigated. Flexible piezoelectric nanogenerators of MASnI 3 and PVDF-MASnI 3 were fabricated by spray coating. The fabricated PVDF-MASnI 3 PENG revealed high piezoelectric performance than that of MASnI 3 PENG. fx1 Highlights • Lead-free MASnI 3 synthesized via a facile approach of ACT method under air ambient. • The phase transition of MASnI 3 from tetragonal to cubic was observed at ~ 30 °C. • MASnI 3 has a dielectric constant of 65 and piezoelectric coefficient of 20.8 pm V−1. • PVDF-MASnI 3 PENG revealed output voltage of 12 V and current density of 4 μA cm−2. • PVDF-MASnI 3 PENG exhibited long-term stability without diminishment in the outputs. [ABSTRACT FROM AUTHOR]

Abstract As future generations of wearable electronics are expected to be directly worn, fiber-based electronics are expected to become increasingly more important in the coming years, as they can be weaved into textiles to provide higher comfort, durability, and integrated multi-functionalities. Herein, we demonstrate an intrinsically stretchable multi-functional hollow fiber capable of harvesting mechanical energy and detecting strain. For energy harvesting, we have utilized a stretchable ferroelectric layer composed of P(VDF-TrFE) in a matrix of elastomer, sandwiched between stretchable electrodes composed of multi-walled carbon nanotubes and PEDOT:PSS. We have demonstrated voltage and current generation under stretching and normal pressure, with output voltage and current as high as 1.2 V and 10 nA, respectively. Furthermore, the hollow architecture enabled the harvesting of pressure coming from internal liquid flow, adding another dimension of harvesting mechanical energy. The stretchable electrodes were used as strain sensors, which exhibited high gauge factor of 80–177 in the 0–50% strain range, along with low hysteresis and durability. These features render our multi-functional fiber highly suitable for wearable electronic applications in the near future. Graphical abstract fx1 Highlights • We developed an intrinsically stretchable multi-functional hollow fiber. • Strain can be detected with high sensitivity (gauge factor up to 177). • The fiber can harvest energy coming from various external mechanical stimuli. • Our fiber has potential in the field of wearable, and robotic applications. [ABSTRACT FROM AUTHOR]

Studies were conducted to evaluate the adequate time for exposure of donor nucleus to oocyte cytoplast before its activation and the effect of oocyte source on the development of SCNT embryos in camels. A higher number of embryos cleaved and developed to blastocyst stage (P < 0.05) when couplets were activated between 1 and 2 h-than that of those activated at 0.5 h or more than 2 h post-fusion. A reduced number of reconstructed embryos cleaved (55.2 ± 7.6%) and developed to the blastocyst stage (20.5 ± 5.5%) when in vitro matured oocytes collected from the slaughterhouse were used as donor cytoplasts, compared to in vitro (71.3 ± 1.3 and 36.7 ± 7.3%) or in vivo matured (91.7 ± 8.3 and 35.4 ± 6.0%) oocytes obtained from live animals (P < 0.05), respectively. However, no differences were observed between the different types of oocyte sources on the establishment of pregnancies and delivery of offspring's. In conclusion, couplets activated 1–2 h post-fusion had higher in vitro developmental potential and oocytes collected from live animals were better in supporting the cleavage and blastocyst production in vitro than oocytes collected from slaughterhouse ovaries, however, all sources of oocytes can be utilized as donor cytoplasts and have the potential to support development of full-term calves after transfer into synchronized recipients. [ABSTRACT FROM AUTHOR]

We report a high-performance flexible piezoelectric generator (PEG) that was based on organic-inorganic lead halide perovskite materials and is operated by controlling the dielectric constant via the partial substitution of Pb 2+ with Fe 2+ in MAPbI 3 . The partial replacement of Pb 2+ with Fe 2+ improved both the morphology and crystallinity of MAPb 1-x Fe x I 3 (0.01 ≤ x ≤ 0.50) films that undergo a tetragonal-cubic phase transition above an incorporated concentration of Fe 2+ (x > 0.07). In addition, the phase transition temperatures of MAPb 1-x Fe x I 3 (0.01 ≤ x ≤ 0.07) films linearly decreased as a function of incorporated concentration, which resulted in a transition temperature for MAPb 1-x Fe x I 3 (x = 0.07) of ~ 45.5 ± 1.5 °C. The dielectric properties as a function of incorporated concentration at room temperature suggested that MAPb 1-x Fe x I 3 (x = 0.07) exhibited a dielectric constant of ~107 and a dissipation factor of 0.02 at 100 kHz. The MAPb 1-x Fe x I 3 (x = 0.07) films exhibited a low leakage current density of ~ 10 −6 at a high applied electric field of 40 kV/cm, and the resultant remanent polarization from saturated ferroelectric P-E hysteresis loops was ~ 1.6 µC/cm 2 . The MAPb 1-x Fe x I 3 (x = 0.07) flexible PEG improved output performance by ~ 7.29 V and current density by ~ 0.88 µA/cm 2 after poling at 30 kV/cm. This was sufficient to instantly light a commercial light-emitting diode (LED) without a storage device. This approach provides a framework that enhances the output performance of organic-inorganic metal halide perovskite materials-based piezoelectric energy harvesters, which could help pave the road to viable, self-powered, wearable electronics. [ABSTRACT FROM AUTHOR]

Experiments were conducted to investigate the development of in vitro matured camel oocytes after their intra-cytoplasmic sperm injection (ICSI) with epididymal sperm collected from slaughtered male camels. Ovaries and testes were collected from a local slaughterhouse in normal saline solution (NSS) at 37 °C and on ice (0–1 °C), respectively. Cumulus-oocyte complexes (COCs) aspirated from the follicles were randomly distributed to 4-well culture plates (20–25 COCs/well) containing 500 μL of maturation medium and cultured at 38.5 °C in an atmosphere of 5% CO 2 in air for about 30 h. Spermatozoa were collected from the cauda epididymites in syringes containing 2–3 mL of tris-tes egg yolk extender. They were cooled down slowly and stored at refrigeration (4 °C) temperature. On the day of use, spermatozoa were prepared by the swim up technique before use in ICSI. The injected oocytes were either activated by ionomycin and roscovitine or put into the culture without any chemical activation. In Experiment 1, presumptive zygotes were fixed and stained with Hoechst 33342 for evaluation of fertilization after 18 h of culture, while, in Experiment 2, they were cultured in 500 μL of the culture medium at 38.5 °C in an atmosphere of 5% CO 2, 5% O 2 and 90% N 2 in air for 7 days to evaluate their development. The proportion of oocytes activated when ICSI was followed by chemical activation was significantly higher (P < 0.05) when compared with non-activated ones. In experiment 2, a higher number of oocytes cleaved (59 vs. 35%) and developed to blastocysts (20 vs. 7%) in the group with post-ICSI activation when compared with the group without chemical activation, respectively. In conclusion, to the best of our knowledge, this is the first report where embryos were produced by ICSI in camels. Chemical activation of oocytes by ionomycin and roscovitine, post -ICSI, enhanced their cleavage and development to blastocyst stage. [ABSTRACT FROM AUTHOR]

Recently two-dimensional layered halide perovskites (2D-layered HPs) with superior piezo-/ferroelectric properties and exceptional environmental stability have become potential alternatives to 3D-HPs. Herein, air-stable 2D-layered 1,3-propanediammonium lead iodide (DAPPbI 4) perovskite is introduced as a promising filler material in a poly(vinylidene fluoride) (PVDF) polymer for the development of a high-performance and mechanically robust DAPPbI 4 –PVDF composite triboelectric nanogenerator (TENG). The triboelectric output performance is noticeably enhanced for 15 wt% DAPPbI 4 owing to its improved electro-active β-phase PVDF (∼90%), high dielectric constant (∼47.4), and high piezoelectric coefficient (∼26.6 pm/V). The TENG achieved a high output voltage of ∼662 V, current density of ∼18.7 µA/cm2, unprecedented high power-density of ∼4.28 mW/cm2, and excellent pressure sensitivity of ∼13.31 V/kPa with outstanding mechanical durability and operational stability. The application of HP-based TENG as a sustainable power source for various portable electronics is demonstrated by charging a Li-ion battery (LIB) in a short time using the TENG output. [Display omitted] • A 2D-layered DAPPbI 4 perovskite as effective filler material in the PVDF matrix for efficient TENG. • Enhanced dielectric, piezoelectric properties of DAPPbI 4 –PVDF composite films. • DAPPbI 4 –PVDF TENG yielded a high recordable power density of ∼4.28 mW/cm2. • Charging of Li-ion battery by DAPPbI 4 –PVDF TENG for self-charging battery-powered electronics. [ABSTRACT FROM AUTHOR]

Optimizing synthesis parameters is crucial in fabricating an ideal cathode material; however, the design space is too vast to be fully explored using an Edisonian approach. Here, by clustering eleven domain-expert-derived-descriptors from literature, we use an inverse design surrogate model to build up the experimental parameters-property relationship. Without struggling with the trial-and-error method, the model enables design variables prediction that serves as an effective strategy for cathode retrosynthesis. More importantly, not only did we overcome the data scarcity problem, but the machine learning model has guided us to achieve cathode with high discharge capacity and Coulombic efficiency of 209.5 mAh/g and 86%, respectively. This work demonstrates an inverse design-to-device pipeline with unprecedented potential to accelerate the discovery of high-energy-density cathodes. [Display omitted] • Inverse-design surrogate model is employed for discharge capacity prediction of lithium-ion batteries cathode materials. • Statistical imputation technique is exploited to solve the missing values and inconsistency in training data. • The proposed method enables the realization of high discharge capacity of 209.5 mAh/g with 86% coulombic efficiency. • We identified eleven descriptors from literature and reverse-engineered the synthesis parameters with high accuracy. [ABSTRACT FROM AUTHOR]

Abstract: An autocatalytic electro-less plating of nickel is attempted to replace an electroless impregnation-reduction (IR) method in ionic polymer–metal composite (IPMC) actuators to reduce cost and processing time. Because nucleation time of Pd–Sn colloids is the determining factor of overall processing time, we used the nucleation time as our control parameter. To optimize nucleation time and investigate its effect on the performance of IPMC actuators, we analyzed the relationship between the nucleation time, interface morphology and electrical properties. The optimized nucleation time was 10h. The trends of the performance and electrical properties as a function of nucleation time were attributed to the fact that the Ni penetration depth was determined by the minimum diffusion length of either Pd–Sn colloids or reducing agent ions. The Ni-IPMC actuators can be fabricated less than 14h processing time without deteriorating performance of the actuators, which is comparable to Pt-IPMC prepared by IR method. [Copyright &y& Elsevier]

Piezoelectric materials are suitable for haptic technology as they can convert mechanical stimuli into electrical signals and vice-versa. However, owing to their disadvantageous mechanical properties such as brittleness (in ceramics) and a low piezoelectric coefficient (in polymers), their application in haptic technology remains challenging. In this paper, we introduce a truss-like 3D hollow nanostructure using zinc oxide (ZnO) that exhibits a drastically improved elastic strain limit while maintaining a piezoelectric coefficient similar to that of single-crystal ZnO. The ZnO hollow nanostructure was fabricated using proximity field nanopatterning (PnP) and atomic layer deposition (ALD) at four different processing temperatures. The piezoelectric characteristics were analyzed through dual AC resonance tracking piezoresponse force microscopy (PFM), and the piezoelectric coefficient was measured to be up to 9.2 pm/V. The nanopillar compression test result showed that the measured elastic strain limit of approximately 10% was at least 3 times greater than the previously reported value. The extended elastic limit of the 3D hollow structure was further supported by finite element simulations. The ZnO hollow nanostructure shows excellent potential for its application to enhanced haptic devices, which mimic the human sense of touch. A 3D ZnO hollow nanostructure exhibits an improved elastic strain limit while maintaining a piezoelectric coefficient similar to that of single-crystal ZnO. This nanostructure is fabricated using atomic layer deposition at four different temperatures. The piezoelectric coefficient of ≈ 9.2 pm/V and elastic strain limit of ≈ 10% are measured by piezoresponse force microscopy and nanopillar compression test, respectively. Image 1 • We developed a 3D ZnO hollow nanostructure through atomic layer deposition and 3D nanolithography. • The effective piezoelectric coefficient of 3D ZnO hollow nanostructure is close to that of a single-crystal bulk ZnO. • The 3D ZnO hollow nanostructure has a high elastic strain limit of 10% which is 3 times greater than the bulk ZnO value. • Our 3D hollow nanostructure can be used in enhanced haptic devices, which mimic the human sense of touch. [ABSTRACT FROM AUTHOR]

Dental erosion has become a prevalence disease and attracted increasing attention worldwide. In this research, we quantitatively evaluate the mechanical and morphological changes in the very early stages of softening and weakening of human enamel surfaces induced by soft drinks using atomic force microscopy (AFM). With an increase of the immersion time in soft drinks, we found a significant increase of surface roughness (R q) of the enamel surface. The prismatic structure of enamel was clearly observed after a 1-h immersion in Coca-Cola®, which shows its strong erosion effect. According to the elastic modulus mapping images obtained by AFM, a considerable decrease of elastic modulus (E) of enamel surface has been found as the enamel surface structures are etched away by soft drinks. A high surface roughness of enamel will result in a high chance of cavities due to easier bacterial adhesion on rougher surface, while a drastic deterioration of the mechanical properties of the enamel will weaken its protection property. Our findings show the serious influence of acidic drinks on enamel surface at the very beginning stage of etching process, which is quite meaningful for people to prevent dental erosion and keep dental health. [ABSTRACT FROM AUTHOR]

Fabric-based wearable electronics are becoming more important in the fourth industrial revolution (4IR) era due to their connectivity, wearability, comfort, and durability. Conventional fabric-based wearable electronics have been demonstrated by several researchers, but still need complex methods or additional supports to be fabricated and sewed in clothing. Herein, a cost-effective, high throughput, and strongly integrated fabric-based wearable piezoelectric energy harvester (fabric-WPEH) is demonstrated. The fabric-WPEH has a heterostructure of a ferroelectric polymer, poly(vinylidene fluoride-co-trifluoroethylene) [P(VDF-TrFE)] and two conductive fabrics via simple fabrication of tape casting and hot pressing. Our fabrication process would enable the direct application of the unit device to general garments using hot pressing as graphic patches can be attached to the garments by heat press. Simulation and experimental analysis demonstrate fully bendable, compact and concave interfaces and a high piezoelectric d 33 coefficient (−32.0 pC N−1) of the P(VDF-TrFE) layer. The fabric-WPEH generates piezoelectric output signals from human motions (pressing, bending) and from quantitative force test machine pressing. Furthermore, a record high interfacial adhesion strength (22 N cm−1) between the P(VDF-TrFE) layer and fabric layers has been measured by surface and interfacial cutting analysis system (SAICAS) for the first time in the field of fabric-based wearable piezoelectric electronics. Image 1 • We developed a highly flexible fabric-based wearable piezoelectric energy harvester. • Our fabrication process using hot pressing and tape casting is very simple and easy to control. • The energy harvester has a record high interfacial adhesion strength between the piezoelectric layer and the fabrics layers. • Our energy harvester has potential in the fields of embedded wearable applications. [ABSTRACT FROM AUTHOR]

There are controversial reports on the restoration of eroded telomere length in offspring produced by somatic cell nuclear transfer (SCNT) in different animal species. To the best of our knowledge, no earlier studies report the telomere length in naturally produced or cloned animals in any of the camelid species. Therefore, the present study was conducted to estimate the telomere length in dromedary camels produced by SCNT, the donor cells, and their age-matched naturally produced counterparts by Terminal Restriction Fragment (TRF) length analysis and real-time Q PCR T/S ratio methods. Genomic DNA was extracted from venous blood collected from 6 cloned animals and their age-matched counterparts. Using the southern blot technique, digested DNA was blotted onto a positively charged nylon membrane, and its hybridization was carried out using telomere (TTAGGG)n specific, DIG-labeled hybridization probe (Roche Diagnostics, Germany) at 42 °C for 4 h. Stringent washes were carried out at the same temperature, followed by a chemiluminescence reaction. The signals were captured using the Azure Biosystems C600 gel documentation system. A TeloTool program from MATLAB software with a built-in probe intensity correction algorithm was used for TRF analysis. The experiment was replicated three times, and the data, presented as mean ± SEM, were analyzed using a two-sample t -test (MINITAB statistical software, Minitab ltd, CV3 2 TE, UK). No difference was found in the mean telomere length of cloned camels when compared to their naturally produced age-matched counterparts. However, the telomere length was more (P < 0.05) than that of the somatic cells used for producing the SCNT embryos. A moderate positive Pearson correlation coefficient (r = 0.6446) was observed between the telomere lengths estimated by TRF and Q PCR T/S ratio method. In conclusion, this is the first study wherein we are reporting telomere length in naturally produced and cloned dromedary camels produced by somatic cell nuclear transfer. We found that telomere lengths in cloned camels were similar to their age-matched naturally produced counterparts, suggesting that the camel cytoplast reprograms the somatic cell nucleus and restores the telomere length to its totipotency stage. • To the best of our knowledge, this is the first study reporting telomere length in any of the camelid species. • Telomere length in cloned camels were similar to those of their age-matched naturally produced counterparts. • The results suggest that the cytoplast of dromedary camel oocytes reprogram and restore the telomere length in embryos constructed by SCNT and maintain its stability during pre- and postnatal developmental stages. [ABSTRACT FROM AUTHOR]

The Korea Pathfinder Lunar Orbiter (KPLO), officially named as Danuri, is the Republic of Korea's first spacecraft to orbit the Moon. The goal of KPLO is to secure core deep space technology for future space exploration in Korea and contribute to lunar science by gathering data from the lunar orbit for one year. This paper presents the results of KPLO's Lunar Orbit Acquisition (LOA) phase in detail, with a particular focus on the operational results of Flight Dynamics (FD). During the LOA phase, the KPLO FD team experienced many expected and unexpected issues. These issues were mitigated by making real-time updates to the LOA phase Design Reference Mission (DRM). The paper also presents the results of the Orbit Determination (OD) and performance of each Lunar Orbit Insertion (LOI) maneuver conducted during the actual flight operation. The importance of considering operational constraints when designing the DRM is emphasized by presenting lessons learned based on actual flight experiences. Unlike the original KPLO LOA phase DRM, KPLO successfully achieved the final mission orbit using only three LOI burns, instead of the planned five LOI burns and an Orbit Trim Maneuver (OTM). Despite the extensive revisions made to the DRM, all mission requirements were still fulfilled during the final lunar orbit insertion, taking into account the significant operational constraints. • Real flight operation results of the Korea Pathfinder Lunar Orbiter's lunar orbit acquisition phase are presented. • Orbit determination and lunar orbit insertion maneuver performance are analyzed based on actual flight data. • Unexpected issues during the actual flight operation were mitigated through real-time updates on the design reference mission. • Considering real-world operational constraints while designing the design reference mission is very critical. [ABSTRACT FROM AUTHOR]

[Display omitted] van der Waals heterostructures (vdWHs), consisting of more than one type of atomically thin 2D crystal layers are emerging platforms for interesting electrical, optical, and catalytic applications. High yield production of vdWHs with atomic scale precision is crucial prerequisite for practical utilization. Here we present a generalized approach of random solution phase, high yield heteroassembly of semiconducting vdWHs by exploiting inherent surface charge states of 2D materials as well as chemical affinity of specific ligand end-functionalities. Facile removal of noncovalent functionalized ligands via simple pH reversal enables clean interfaces within vdWHs, yielding outstanding optoelectrical and electrochemical properties driven by fluent interfacial charge transfer among the layered 2D structures. The generality of this procedure is demonstrated by the formation of a series of different vdWHs such as WSe 2 -MoS 2 , graphene–MoS 2 - and phospherene–WSe 2 heterostructures. Atomically thin WSe 2 –MoS 2 phototransistor displayed an exceptionally fast response time with high sensitivity. Graphene–MoS 2 overcomes the inherent charge transfer issue of MoS 2 for electrochemical catalyst. Phospherene–WSe 2 successfully addresses poor ambient stability of phospherene together with enhanced surface activity towards chemical sensing. [ABSTRACT FROM AUTHOR]

Abstract: The permanent rivers and streams of the United States – i.e. the “blue lines” from the United States Geological Survey (USGS) maps – are available in a Geographic Information System dataset called NHDPlus in which network connectivity for approximately three million reaches is known. The USGS also measures stream flow at about twenty thousand gauges whose locations are known exactly on NHDPlus rivers. The Routing Application for Parallel computatIon of Discharge (RAPID) is a river network model that can be run on NHDPlus if given inflow to rivers from runoff. The second phase of the North American Land Data Assimilation System (NLDAS2) provides runoff estimates from four land surface models over the continent. One could therefore combine RAPID with NLDAS2 runoff to compute stream flow in all NHDPlus “blue lines” and compare computations with USGS observations over the United States. The work presented here investigates such a combination but focuses on the Texas Gulf Coast Hydrologic Region as a test case for regional-scale river flow modeling using off-the-shelf runoff products, thousands of mapped rivers and hundreds of stream flow gauges. Despite initial difficulties in the determination of water inflow from gridded NLDAS2 runoff datasets to NHDPlus rivers, the “blue line” approach is shown to be advantageous partly because hundreds of gauges are easily located on river networks and used throughout basins. Such use of a large number of gauges allows for new investigations related to the analysis of flow computations and to the optimization of model parameters thereby bridging the gap between continental-scale environmental modeling and local-scale planning and decision making. The quality of NLDAS2 runoff relative to locally-calibrated data is assessed through comparison between computed and observed river flow. With the exception of large outliers at a few gauges, the best NLDAS2 runoff products perform similarly to the regional dataset. Such outliers prevent the successful optimization of river model parameters but a careful selection of what stations to use for optimization is shown to overcome this difficulty. While river model parameters determined separately for each runoff dataset allow obtaining best results, a single set of parameters is sufficient to assess the relative quality of runoff datasets. The detailed NHDPlus description of river reaches also allows investigating the impact of increased spatial variability in model parameters which – following optimization of model computations – suggests that those parameters of reaches located on the main stems of large rivers tend to have the largest influence on the quality of flow simulations. [Copyright &y& Elsevier]

Despite the significant advancements of dielectric materials, the energy density values of dielectric capacitors are extremely low compared to those of other energy storage systems, e.g., batteries and fuel cells. The deposition of solid solution of ferroelectric and paraelectric multicomponent thin films are the most widely used approach to enhance the energy density of dielectric capacitors; however, it is extremely difficult to determine the optimized composition ratio of two or three components. In this study, we develop ultrahigh energy density single-component Sn-doped BaTiO 3 (BTS) epitaxial thin film capacitors. An ultrahigh energy density of 92.5 J/cm3 and energy efficiencies above 78% were successfully achieved in (111)-oriented BTS epitaxial thin film capacitors. These excellent results were attributed to the formation of multi-nanodomains accompanied by delayed polarization saturation, low remnant polarization, high breakdown strength, and high cycling stability. Engineering multi-nanodomains through chemical doping and epitaxial orientation is a facile approach to develop energy-efficient ultrahigh energy density capacitors. This approach can be extended for the design of other single-component-based energy-efficient dielectric capacitors with ultrahigh energy density. [Display omitted] [ABSTRACT FROM AUTHOR]

The ability to quickly analyze large imaging datasets is vital to the widespread adoption of modern materials characterization tools, and thus the development of new materials. Image segmentation can be the most subjective and time-consuming step in the data analysis workflow. A promising approach to segmentation of large materials datasets is the use of convolutional neural networks (CNNs). However, a major challenge is to obtain the images and segmentations needed for CNN training, since this requires segmentations performed by humans. We show that it is possible to segment experimental materials science data using a SegNet-based CNN that was trained only using simple phase field simulations. A test image from an in-situ solidification experiment of an Al-Zn alloy was used to parameterize the phase field simulations. The most important microstructural features required for the best CNN to "understand" the contents of the image are ranked as: (1) having training images with diffuse particle-background interfaces, (2) modifying the images by adding noise, (3) removing particles at the image edges, and (4) adding sub-images to the particles to account for the feint bands present on some dendrites. The CNN trained on phase field images segmented the experimental test image with 99.3% accuracy, comparable to CNNs trained on experimental data. This approach of using computationally generated images to train CNNs capable of segmenting experiments will accelerate the rate of materials design and discovery. [Display omitted] [ABSTRACT FROM AUTHOR]

Y 2 O 3 coating on Al 2 O 3 substrate was prepared by atmospheric plasma spray (APS). Computational fluid dynamics (CFD) was carried out to predict the state of in-flight Y 2 O 3 particles at different powder feeding rates. Microstructure and mechanical properties were found to be affected by the spray distance and powder feeding rate. In this study, the hardness was calculated using a field emission-scanning electron microscope (FE-SEM) because the indentation in the coating is too small to measure using a hardness test machine. The formation of pores causes a decrease in the mechanical property, and the pore length of over 10 μm substantially decreases the hardness. Meanwhile, the solidification behavior is affected by the maximum temperature of the in-flight particles. Based on computational fluid dynamics (CFD) analysis, the maximum temperature of the in-flight particles was found to decrease with increase of the powder feeding rate at the same spray distance. At the powder feeding rate of 60 g/min, a lower adhesion strength was confirmed than that at feeding rate of 30 g/min because splats were insufficiently spread due to the lower maximum temperature of the in-flight particles. The roughness and height of the coating surface were evaluated by confocal microscopy and atomic force microscopy(AFM) analyses. The roughness is the resultant of accumulated splats and the accumulation mechanism of splats is affected by the state of the in-flight particles. Furthermore, there were nano-scale differences of height on the splat surface, on which the nucleation looks like 'rugged bark' during solidification of splats when the in-flight particles impact the substrate. [ABSTRACT FROM AUTHOR]

Abstract Lithium metal is considered one of the most promising anode materials for realizing high volumetric and gravimetric energy density, owing to the high specific capacity (∼3860 mAh g−1) and the low electrochemical potential of lithium (−3.04 V vs. the standard hydrogen electrode). However, undesirable dendritic lithium growth and corresponding instability of the solid electrolyte interphase prevent safe and long-term use of lithium metal anodes. This paper presents a simple electrolyte approach to enhance the performance of lithium metal batteries by tuning the dielectric constant of the liquid electrolyte. Electrolyte formulations are designed by changing the concentration of ethylene carbonate to have various dielectric constants. This study confirms that high ethylene carbonate content in a liquid electrolyte enhances the cycling performance of lithium metal batteries because the electric field intensity applied to the electrolyte is reduced in relation to the polarization of the electrolyte and thus allows smooth lithium plating and formation of a stable solid electrolyte interphase. We believe that this approach provides an important concept for electrolyte system design suitable to lithium metal batteries. Highlights • Electric field intensity for lithium plating is derived from interface analysis. • Electrolytes with different dielectric constants are designed systematically. • Confirmed enhanced cycling performance of lithium occurs with high EC content. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Graphene and graphene-based systems have recently been recognized as promising platforms for energy harvesting, microelectronic components and energy storage owing to their excellent electrical and thermal conductivity, outstanding mechanical properties, good chemical stability, area adaptability, among other significant properties. Integration of energy harvesting systems relying on the graphene/graphene-based materials in contact with fluids has been emphasized in recent years, as well as their potential impact on electric energy generation for a wide range of applications (e.g. innovative medical devices, advanced electronic systems and highly-efficient transduction systems for renewable energy). This review summarizes, for the first time, major breakthroughs carried out in the scope of energy harvesting exploiting graphene-based material systems (comprising graphene films, graphene grids, graphene membranes, 3D graphene composites and tribological structures) in contact with ionic and non-ionic fluids. Several transduction mechanisms for energy harvesting have been thoroughly analyzed. Energy outputs, materials and structures, substrates, types of fluid, manufacture methodologies, and experimental test methodologies are systematically highlighted in this review. Finally, future research directions and innovative applications of these harvesters are proposed. [ABSTRACT FROM AUTHOR]

We report a non-contact type polyvinylidene fluoride (PVDF)-based liquid volume sensor. When a liquid container vibrates due to an applied impact, our sensor that is attached to the wall of the container detects the resonance frequency of vibration, which shifts as a result of change in liquid volume. The sensitivity of our sensor was enhanced by stacking multiple sensors in series. A PVDF bimorph actuator was also fabricated to demonstrate an integrated actuator-sensor system. We believe that the results presented in this work will pave the way for novel applications in volume sensing. [ABSTRACT FROM AUTHOR]

The projections of species distribution models (SDMs) have provided critical knowledge for conservation planning under climate change in the Republic of Korea. However, uncertainty about the SDM projections has been criticized as a major challenge to reliable projections. The present research investigated uncertainty among competing models (Model uncertainty) and uncertainty of future climate conditions (climate uncertainty) driving from different GCMs and CO 2 emission scenarios in predicting the future distributions of plants. For this purpose, using nine single-model algorithms and the pre-evaluation weighted ensemble method, we modeled the geographical distributions of Silver Magnolia ( Machilus thunbergii Siebold & Zucc.), a warm-adapted evergreen broadleaved tree; furthermore, we predicted its future distributions under 20 climate change scenarios (5 global circulation models (GCMs) × 4 CO 2 emission scenarios (RCPs)). The results showed a great variation in the accuracies of nine single-model projections: the mean AUC values of nine single-models ranged from 0.764 (SER) to 0.970 (RF), and the mean TSS ranged from 0.529 (SRE) to 0.852 (RF). RF (mean AUC = 0.970, mean TSS = 0.852) and the ensemble forecast (AUC = 0.968, TSS = 0.804) showed the highest predictive power, while SRE showed the lowest. The future distributions of Silver Magnolia projected with the ensemble SDM clearly varied according to GCMs and RCPs. The twenty climate scenarios produced twenty different projections of the magnolia prospective distribution. GCMs commonly projected the maximum range expansion under RCP 8.5 in 2050 and 2070, but CO 2 emission scenarios explaining the minimum expansions differed according to GCMs. In conclusion, our results show that GCMs, CO 2 emission scenarios and SDM algorithms produce considerable variations in the SDM projections. Therefore, this research suggests that understanding of model and climate uncertainties is critical for an effective conservation planning in forest management under climate change on the Korean Peninsula. [ABSTRACT FROM AUTHOR]

[Display omitted] • Tensile stress relaxation by the modulation of interfacial residual stress. • Residual stress modulation by controlling material properties and process temperature. • Coefficient of thermal expansion and elastic modulus control in the copolymer system. • Remaining barrier property after bending cycle with the tensile strain of 1.09 % • Developed thin film encapsulation system was successfully applied to OLED. Thin film encapsulation (TFE) is an essential component for reliable operation of organic electronic devices. However, the brittleness of inorganic layer in TFE must be resolved to secure the long-term stability of flexible/bendable devices. In this study, the robustness of the TFE in mechanical deformation is improved by harnessing such an interfacial residual stress. During fabrication of TFE by the alternating deposition of the organic layer via initiated chemical vapor deposition (iCVD) and inorganic Al 2 O 3 via atomic layer deposition (ALD), the lower process temperature of iCVD (30 ℃) than that of ALD (90 ℃) generates a residual stress at the organic/inorganic interface, which was optimized by controlling the organic layer thickness, coefficient of thermal expansion (CTE), and elastic modulus. In order to optimize the residual stress, a new type of copolymer layer was suggested in TFE, synthesized from cyclohexyl acrylate (CHA) and 1,3,5-trimethyl-1,3,5-trivinylcyclosiloxane (V3D3) monomers. The water vapor transmission rate (WVTR) of the fabricated TFE was 3.1 × 10-5 g/m2·day, which was fully retained by optimized residual stress after 1000 times of bending cycles with the bending radius of 2.3 R, corresponding to the tensile strain exceeding 1.09%. [ABSTRACT FROM AUTHOR]

Termination and hydration of the forsteritic (Fo90Fa10) olivine (0 1 0) surface have been investigated with high-resolution specular X-ray reflectivity and Atomic Force Microscopy. The surface was prepared by polishing a naturally grown {0 1 0} face, from which we found the polished surface in acidic (pH 3.5) alumina suspension exhibits regular steps while the basic (pH 9.5) silica polished surface is irregularly roughened, indicating there are two distinguishable mechanochemical processes for the surface dissolution. The quantitative interpretation of the regular steps from the alumina-polished surface suggests that the observed step heights correspond to multiples of crystallographic unit cell. Only this atomically terraced surface is investigated with the high-resolution X-ray reflectivity (HRXR) to determine the surface termination and hydration. The basic silica paste polished surface turned out too rough to measure with X-ray reflectivity. HRXR reveals that the alumina polished olivine (0 1 0) surface in pure water is terminated at a plane including half-occupied metal ion sites (M1), an oxygen vacancy site, and a silicate tetrahedral unit with one of its apices pointing outward with respect to the surface. An ideal termination with the oxygen vacancy would fulfill the stoichiometry of the formula unit; however, in the observation, the vacancy site is filled by an adsorbed water species and about a quarter of the remaining metal ions are further depleted. The terminating plane generates two distinct atomic layers in the laterally averaged electron density profile, on which two highly ordered adsorbed water layers are formed. The first layer formation is likely through the direct interaction with the M1 plane and the second layer is likely through the hydrogen bonding interaction with the first water layer. With this multilayered adsorbed water structure, the surface metal ion is partially hydrated by the vacancy-filling water species and adsorbed water molecules. The bulk water links to these distinct adsorbed water layers, with weak density oscillations that almost completely damp out after the first bulk water layer. The total thickness of the layered water structure including the two distinct adsorbed layers and the first layer of bulk water is slightly less than 1 nm, which corresponds to roughly three molecular layers of water. These results describe the steric constraints of the surface metal ion hydration and the iron redox environment during water–olivine interactions in this particular crystallographic orientation. [ABSTRACT FROM AUTHOR]

• The high-rate electrochemical performance of NCM333, NCM622, and NCM811 is compared. • The effects of VC and PS as electrolyte additives are evaluated. • Cathode SEI on the NCM materials are analyzed by XPS. The high-rate half-cell performance of LiNi 0.3 Co 0.3 Mn 0.3 O 2 (NCM333), LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622), and LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode materials is investigated with the base electrolyte of LiPF 6 /ethylene carbonate (EC):ethylmethyl carbonate (EMC) and the additives of vinylene carbonate (VC) and 1,3-propane sultone (PS). The effects of these additives on the cathode surfaces are particularly examined in terms of the reduction products of the electrolyte components and the formation of solid electrolyte interphase (SEI) on cathode surfaces. The cathode SEI appears less after formation for all NCM materials, but it accumulates with repeated charging/discharging at a high rate. Of these, the addition of VC + PS to the base electrolyte sufficiently provides stable cathode SEI with suppressed thickness under cycling at a high rate by inhibiting the further decomposition of reduction products. The synergy of VC + PS may be originated by the combination of vinyl and sulfone functional groups to provide passivation film with cross-linked protective networks on Ni-rich NCM cathode materials. Thus, superior cycle performance is achieved, especially for NCM811. [ABSTRACT FROM AUTHOR]