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Developing catalysts with outstanding performance for oxygen evolution reaction (OER) is crucial to advance energy conversion technologies. In these regards, catalysts based on 3d transition metals have recently attracted much attention, yet further development is required. Here, we present a new type of heterostructure catalyst in which CoO nanowire arrays are hybridized with tungsten nanoparticles (W-CoO), and are self-supported on conductive carbon cloth (CC). Electronic coupling effects at the W-CoO heterointerface promote electron transfer and OER kinetics to expedite the formation of oxyhydroxide species, which are the active sites for OER processes. A variety of in situ and ex situ characterization methods are employed to reveal deep insights into surface transformations and investigate the relationship between the conversion to oxyhydroxide moieties and OER performance. This report presents new understanding of the rational design and synthesis of catalysts that exhibit outstanding performance as electrochemical water splitting electrode for OER.

Objective: Endoscopic surgical procedures rigorously underscore the significance of rapid hemostasis for unavoidable intraoperative bleeding, requiring advancement of the immediate hemostatic interventions for favorable clinical outcomes. Here, we report the efficacy of a new optical treatment with dual-wavelengths to develop an endoscopic hemostasis method. Methods: we combine visible (20-W 532 nm at 1.1 kW/cm2) and near-infrared (40-W 980 nm at 2.2 kW/cm2) wavelengths for facilitating noncontact thermal hemostasis on venous and arterial bleeders in in vivo leporine models. Results: Simultaneous irradiation of 60-W dual-wavelengths allows for an increased irradiance of 3.3 kW/cm2, involving both rapid light absorption by hemoglobin and deep thermal penetration. The collective thermal effects from the combined wavelengths contribute to a significant reduction in coagulation time and a high success rate of complete hemostasis for both venous and arterial bleeders. The enhanced hemostatic potential of the dual-wavelengths treatment accompanies minimal hemorrhage, reduces inflammatory responses, and facilitates re-epithelialization. Conclusion: The proposed dual-wavelengths method can achieve rapid and complete hemostasis for endoscopic procedures. Significance: We present the high-irradiance photothermal treatment using the dual-wavelengths as a novel method to regulate venous and arterial bleeding and potentially as a rapid noncontact hemostasis option to mitigate the risk associated with significant blood loss.

The design of active and stable electrocatalysts for oxygen evolution reaction is a key enabling step toward efficient utilization of renewable energy. Along with efforts to develop high-performance electrocatalysts for oxygen evolution reaction, pyrochlore oxides have emerged as highly active and stable materials that function as catalysts as well as conductive supports for hybrid catalysts. The compositional flexibility of pyrochlore oxide provides many opportunities to improve electrocatalytic performance by manipulating material structures and properties. In this Outlook, we first discuss the recent advances in developing metallic pyrochlore oxides as oxygen evolution catalysts, along with elucidation of their reaction mechanisms, and then introduce an emerging area of using pyrochlore oxides as conductive supports to design hybrid catalysts to further improve the OER activity. Finally, the remaining challenges and emerging opportunities for pyrochlore oxides as electrocatalysts and conductive supports are discussed., This Outlook summarizes recent advances in pyrochlore oxides as oxygen evolution catalysts and introduces a new approach using pyrochlore oxides as a conductive support to design hybrid catalysts.

Simulation involving interaction with deformable objects often causes stability problems because a slowly updated force generates additional energy to the human user. This paper proposes a stable and transparent haptic rendering for simulation involving interaction between a rigid tool and deformable objects. This method computes visual and haptic feedback in the simulation and haptic feedback loops, respectively. A local stiffness matrix consisting of points around contact points is constructed based on collision detection between a virtual tool and a deformable object in the simulation loop. The haptic feedback is then computed at a higher update rate in the haptic feedback loop using the local stiffness matrix. Equivalent springs computed by using the equivalent stiffness energy are added to the boundary of the local stiffness matrix to minimize errors in the rendered force. The proposed method is compared with the virtual coupling widely used in simulation involving interaction with deformable objects. The proposed method reduces the x -, y -, and z -axis maximum force errors by up to 52%, 80%, and 70%, respectively, compared to the virtual coupling in the simulation involving interaction with the Stanford bunny object consisting of 2087 points and 9997 tetrahedrons.

With the lightening of the mobile devices, thinning of electrolytic copper foil, which is mainly used as an anode collection of lithium secondary batteries, is needed. As the copper foil becomes ultrathin, mechanical properties such as deterioration of elongation rate and tear phenomenon are occurring, which is closely related to microstructure. However, there is a problem that it is not easy to prepare and observe specimens in the analysis of the microstructure of ultrathin copper foil. In this study, electron backscatter diffraction (EBSD) specimens were fabricated using only mechanical polishing to analyze the microstructure of 8 μm thick electrolytic copper foil in plane view. In addition, EBSD maps and transmission electron microscopy (TEM) images were compared and analyzed to find the optimal cleanup technique for properly correcting errors in EBSD maps.

Heat pipe technology with latent heat has been a rising topic for various engineering applications such as electric cars and high-power computer chips. It has been studied for thermal resistance and model development as they are the key to infer effective thermal conductivity. In this article, computational fluid dynamics is investigated to look at the two-phase flow and heat transfer of a two-phase thermosyphon of which inside cannot be visualized experimentally. The Volume-of-Fluid model has been utilized as well as the Lee model. Thermal resistance tendencies are also examined for different amounts of water, heat pipe diameter, and heater power. As a result, the thermal resistance decreases when the water amount, heat pipe diameter, and heater power increase, indicating that temperature is quickly cooled down by latent heat. The thermal resistance for different conditions is modeled with a simple scaling analysis, and a good agreement is made between the model and the numerical results. Effective thermal conductivity is also calculated based on the thermal resistance results. An increase in thermal conductivity is observed as the diameter decreases, indicating the importance of an optimum thermosyphon design.

Microbial lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of crystalline polysaccharides including chitin and cellulose. The discovery of a large assortment of LPMO-like proteins widely distributed in insect genomes suggests that they could be involved in assisting chitin degradation in the exoskeleton, tracheae and peritrophic matrix during development. However, the physiological functions of insect LPMO-like proteins are still undetermined. To investigate the functions of insect LPMO subgroup I-like proteins, which contain an AA15 LPMO catalytic domain and a conserved C-terminal cysteine-rich motif, two evolutionarily distant species, Tribolium castaneum and Locusta migratoria, were chosen for study. RNAi for the T. castaneum protein, TcLPMO1, caused molting arrest at all developmental stages, whereas RNAi of the L. migratoria protein, LmLPMO1, prevented only adult eclosion. In both species, LPMO1-deficient animals were unable to shed their exuviae and died. TEM analysis revealed failure of turnover of chitinous cuticle, which is critical for completion of molting. Purified recombinant LPMO1-like protein from Ostrinia furnacalis (rOfLPMO1) exhibited oxidative cleavage activity and substrate preference for chitin. These results reveal for the first time the physiological importance of catalytically active LPMO1-like proteins from distant insect species and provide new insight into the enzymatic mechanism of chitin turnover during molting.

Microbial lytic polysaccharide monooxygenases (LPMOs) catalyze the oxidative cleavage of crystalline polysaccharides including chitin and cellulose. The discovery of a large assortment of LPMO-like proteins widely distributed in insect genomes suggests that they could be involved in assisting chitin degradation in the exoskeleton, tracheae and peritrophic matrix during development. However, the physiological functions of insect LPMO-like proteins are still undetermined. To investigate the functions of insect LPMO15 subgroup I-like proteins (LPMO15-1s), two evolutionarily distant species, Tribolium castaneum and Locusta migratoria, were chosen. Depletion by RNAi of T. castaneum TcLPMO15-1 caused molting arrest at all developmental stages, whereas depletion of the L. migratoria LmLPMO15-1, prevented only adult eclosion. In both species, LPMO15-1-deficient animals were unable to shed their exuviae and died. TEM analysis revealed failure of turnover of the chitinous cuticle, which is critical for completion of molting. Purified recombinant LPMO15-1-like protein from Ostrinia furnacalis (rOfLPMO15-1) exhibited oxidative cleavage activity and substrate preference for chitin. These results reveal the physiological importance of catalytically active LPMO15-1-like proteins from distant insect species and provide new insight into the enzymatic mechanism of cuticular chitin turnover during molting.

van der Waals heterostructures composed of two-dimensional materials vertically stacked have been extensively studied to develop various multifunctional devices. Here, we report WSe

The sodium-air (Na–air) batteries are considered as a new promising energy storage devices due to their 1683 W h kg−1 of high theoretical specific energy density. However, these outstanding theoretical energy density performances cannot be achieved because undesirable sluggish oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) reaction kinetics on the air cathode side causes the high overpotential gap and low round-trip efficiencies during charge-discharge process. Therefore, the development of highly active bifunctional oxygen electrocatalysts is the key strategy to obtain the low overpotential gap with high energy density performance of Na-air batteries. In this work, a novel single crystalline thallium ruthenium oxide (Tl2Ru2O7) with pyrochlore structure was firstly revealed as an effective bifunctional electrocatalyst. Moreover, in order to enhance the surface chemical reactivity of Tl2Ru2O7, the surface of Tl2Ru2O7 is functionalized by using the dihydrogen phosphate ion (P-Tl2Ru2O7) for achieving the effective and rapid charge transfer behavior. The superior bifunctional catalytic activity of P-Tl2Ru2O7 can be explained by the degree of covalency of Ru-O bonds in Tl2Ru2O7 and enhanced covalent character by functionalized dihydrogen phosphate ion, which can afford favorable oxidation nature to Tl and Ru ions.

The sodium-air (Na-air) batteries are spotlighted as state-of-the-art electrical energy storage system, because of their high sodium-ion conductivity and specific energy density performance. However, the undesirable sluggish oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) kinetics limit the practical production of rechargeable Na-air batteries. Therefore, it is essential to develop highly effective bifunctional electrocatalysts for OER and ORR. Although the pyrochlore oxides (A2B2O7) exhibits great potential for highly-active bifunctional electrocatalyst, the lack of studies regarding to A-site cations have hindered the development of new pyrochlore catalysts with comprehensive understanding of catalytic activity. In this work, we report the use of a novel nanocrystalline bismuth ruthenate pyrochlore oxide (Bi2Ru2O7) as an effective oxygen electrocatalyst by using the favorable oxidation nature of Bi and Ru ions in Bi2Ru2O7. Further, the oxidized cations can donate the electrons to the surface and inner layers, providing the low-resistance pathway during OER and ORR. Finally, the bifunctional electrocatalytic activities of Bi2Ru2O7 are successfully translated to a practical device, an aqueous Na-air battery, for the first time.

We developed a guinea fowl jumping robot with a one-axis momentum wheel mechanism with a passive hallux model. The Guinea fowl jumping robot was able to perform stable vertical jumping due to the linkage structure designed as a passive hallux model. Furthermore, we used the one-axis momentum wheel mechanism in the jumping robot for making the compact balance control mechanism that can control the body angle of the robot. Through the experiment, the conventional jumping robot uses the inertial tail to adjust the body angle in the air for stable landing and jumping. However, in the case of an inertial tail, it has a large volume and has a disadvantage in that stability is highly reduced when it collides with obstacles due to the shape of the inertial tail. Moreover, we performed a theoretical analysis, simulation, and experiment to verify the performance of the momentum wheel mechanism, and we confirmed that the passive hallux structure contributed to the jumping stability. Besides, we proved that the momentum wheel could adequately land on the ground by adjusting the body angle after vertical jumping. In addition, we demonstrated that the stability of the momentum wheel is higher than the inertial tail through collision simulation.

Ir and its oxide are the only available oxygen evolution reaction (OER) electrocatalysts with reasonably high activity and stability for commercial proton-exchange membrane electrolyzers. However, the establishment of structure–performance relationships for the design of better Ir-based electrocatalysts is hindered by their uncontrolled surface reconstruction during OER in acidic media. Herein, we monitor the structural evolution of two model Ir nanocrystals (one with a flat surface enclosed by (100) facets and the other with a concave surface containing numerous high-index planes) under acidic OER conditions. Operando X-ray absorption spectroscopy measurements reveal that the promotion of surface IrOx formation during the OER by the concave Ir surface with high-index planes results in a gradual OER activity increase, while a decrease in activity and limited oxide formation are observed for the flat Ir surface. After the activation process, the Ir concave surface exhibits ~ 10 times higher activity than the flat surface. Density functional theory computations reveal that Ir high-index surfaces are thermodynamically preferred for the adsorption of oxygen atoms and the formation of surface oxides under OER conditions. Thus, our work establishes a structure–performance relationship for Ir nanocrystals under operating conditions, providing new principles for the design of nanoscale OER electrocatalysts.

Resonant elastic X-ray scattering has been widely employed for exploring complex electronic ordering phenomena, like charge, spin, and orbital order, in particular in strongly correlated electronic systems. In addition, recent developments of pump-probe X-ray scattering allow us to expand the investigation of the temporal dynamics of such orders. Here, we introduce a new time-resolved Resonant Soft X-ray Scattering (tr-RSXS) endstation developed at the Pohang Accelerator Laboratory X-ray Free Electron Laser (PAL-XFEL). This endstation has an optical laser (wavelength of 800 nm plus harmonics) as the pump source. Based on the commissioning results, the tr-RSXS at PAL-XFEL can deliver a soft X-ray probe (400-1300 eV) with a time resolution about ~100 fs without jitter correction. As an example, the temporal dynamics of a charge density wave on a high-temperature cuprate superconductor is demonstrated., 7 figures, 2 tables

Chalcogenide-based materials have attracted widespread interest in high-performance thermoelectric research fields. A strategy for the application of two types of chalcogenide for improved thermoelectric performance is described herein. Tin selenide (SnSe) is used as a base material, and Te nanoneedles are crystallized in the SnSe, resulting in the generation of a composite structure of SnSe with Te nanoneedles. The thermoelectric properties with various reaction times are investigated to reveal the optimum conditions for enhanced thermoelectric performance. A reaction time of 4 h at 450 K generated a composite Te nanoneedles/SnSe sample with the maximum ZT value, 3.2 times larger than that of the pristine SnSe. This result is attributed to both the reduced thermal conductivity from the effective phonon scattering of heterointerfaces and the improved electrical conductivity value due to the introduction of Te nanoparticles. This strategy suggests an approach to generating high-performance practical thermoelectric materials.

Laser lights have been used by dermatologists for tattoo removal through photothermal interactions. However, most clinical studies used a visual scoring method to evaluate the tattoo removal process less objectively, leading to unnecessary treatments. This study aimed to develop a simple and quantitative imaging method to monitor the degree of tattoo removal in in vivo skin models. Sprague Dawley rat models were tattooed with four different concentrations of black inks. Laser treatment was performed weekly on the tattoos using a wavelength of 755 nm over six weeks. Images of non-treated and treated samples were captured using the same method after each treatment. The intensities of the tattoos were measured to estimate the contrast for quantitative comparison. The results demonstrated that the proposed monitoring method quantified the variations in tattoo contrast after the laser treatment. Histological analysis validated the significant removal of tattoo inks, no thermal injury to adjacent tissue, and uniform remodeling of epidermal and dermal layers after multiple treatments. This study demonstrated the potential of the quantitative monitoring technique in assessing the degree of clearance level objectively during laser treatments in clinics.

The third-generation synchrotron radiation accelerator has been providing beams to users since 1995 and have been made to upgrade the performances of the accelerators and the experimental devices. For that reason, the PLS-II was started in 2009 as a three-year project. An important feature is the extension of the ID (insertion device) beamline and the efficient placement of the storage ring magnet structure. The overall structure of the beamline as well as the length and structure of the front end had to be changed to expand the ID beamline. Also, the safety of many vacuum parts that would be exposed to the large heat due to the increase in the beam energy was firstly considered in the design, and an analysis was performed in parallel. This paper describes the overall structure of the front end, including the design and analysis of the vacuum components in the Pohang Light Source(PLS)-II beamline.

Graphitic carbon nitride/mesoporous carbon sphere composites were successfully synthesized using a simple, three-step treatment, and the effects of the mesoporous carbon sphere (MPCS) content on the electrochemical properties of the composites were studied. The MPCSs were homogeneously captured and dispersed on the prepared graphitic carbon nitride (GCN), forming a GCN/MPCS nanocomposite structure. These composite materials exhibited better electrochemical properties than previously reported electric double-layer capacitor (EDLC) materials, such as carbon nanotubes, graphene, activated carbon, and carbon spheres. The addition of a small amount of mesoporous carbon spheres, typically 1:2 by weight (GCN/MPCS), to form GCN/MPCS(2) resulted in an excellent specific charge capacity of 352.44 F g−1 at a scan rate of 5 mV s−1. These results indicate the potential of the composite for the development of highly capacitive energy storage devices with practical applications.

The unique designed and their tunable intrinsic active sites for OER have a key role in alternating the noble metal (IrO2). Herein, we fabricated Co-Ni-N-S-O nanocage through a simple self-catalytic process. The outstanding OER performance is based on the rich defect sites and oxygen vacancies in the amorphous phase with abundant surface area attributed to the hollow nanocage structure, and the ‘ensemble effect’ caused by N and S doping. The high intrinsic active surface area of Co-Ni-N-S-O was confirmed by double-layer capacitance (Cdl: 5.39 mF/cm2), and the ‘ensemble effect’ was determined through XPS and XAS analysis. The metal centers were located to a higher oxidation state, resulting the advantageous for the formation of OER intermediates (*OOH), as proved by operando XAS analysis. The Co-Ni-N-S-O catalyst provides a valuable strategy to design electrocatalysts of high efficiency and expand the applications of catalysts based on amorphous metal oxides.

Augmented reality medical training simulators can provide a realistic and immersive experience by overlapping the virtual scene on to the real world. Latency in augmented reality (AR) medical training simulators is an important issue as it can lead to motion sickness for users. This paper proposes a framework that can achieve real-time rendering of the 3D scene aligned to the real world using a head-mounted display (HMD). Model deformation in the 3D scene is categorised into local deformation derived from user interaction and global deformation determined by the simulation scenario. Target shapes are predefined by a simulation scenario, and control points are placed to embed the predefined shapes. Free-form deformation (FFD) is applied to multiple shapes to efficiently transfer the simulated model to the HMD. Global deformation is computed by blending a mapping matrix of each FFD with an assigned weighting value. The local and global deformation are then transferred through the control points updated from a deformed surface mesh and its corresponding weighting value. The proposed framework is verified in terms of latency caused by data transmission and the accuracy of a transmitted surface mesh in a vaginal examination (VE) training simulation. The average latency is reduced to 7 ms, less than the latency causing motion sickness in virtual reality simulations. The maximum relative error is less than 3%. Our framework allows seamless rendering of a virtual scene to the real world with substantially reduced latency and without the need for an external tracking system.

The 3d transition metal-based catalysts have emerged as prospective electrocatalysts for the oxygen evolution reaction (OER) owing to the wide availability of transition metals in the Earth’s crust, as well as the low cost and long lifetime of the catalysts. However, their moderate activity for the OER is a challenge for commercial applications. In this study, a heterostructure (W@Ni(OH)2/CC) composed of Ni(OH)2 nanosheets and tungsten nanoparticles was successfully synthesized on a conductive carbon cloth to overcome the problem of deficient catalytic activity. The constructed heterointerface and the two-dimensional (2D) nanosheet morphology of the catalyst can accelerate the charge transfer, OER kinetics, and the ion/gas transport. In addition, interfacial electronic structure optimization was investigated to facilitate the formation of oxyhydroxide intermediates on the catalyst surface, which enhances the overall OER performance. This paper provides a thorough explanation on the role of modified electronic configuration in the heterostructures and proposes a new path to synthesize these heterostructures.

The photon beam position monitor (PBPM) plays a critically important role in the accurate monitoring of the beam position. W (Wire)-PBPMs are installed at the front end and photon transfer line (PTL) of the diagnostic beamline and detect the change of position and angle of the beam orbit applied to the beamline. It provides beam stability and position data in real time, which can be used in feedback system with BPM in storage-ring. Also it provides beam profile, which makes it possible to figure out the specifications of beam. With two W-PBPMs, the angle information of beam could be acquired and the results coupled with beam profile are used with orbit correction. The W-PBPM has been designed and installed in the diagnostic beamline at Pohang Light Source. Herein the details of the design, analysis and performance for the W-PBPM will be reported.

Micro- and mesoporous silicon carbide (SiC)/ferroferric oxide (Fe 3 O 4 ) composites (SiC/Fe 3 O 4 ) were prepared (to develop novel supercapacitor electrode materials) via chemical deposition of Fe 3 O 4 on SiC surfaces by chemical reduction of an Fe precursor. Based on the synergistic contributions between the electric double layer capacitive contribution of SiC and the pseudocapacitive contribution of Fe 3 O 4 , the SiC/Fe 3 O 4 electrode exhibits outstanding charge storage capacity, exhibiting a specific capacitance of 423.2 F g −1 at 5 mV s −1 with high capacitance retention ratio over a wide range of scan rates (81.8% at 500 mV s −1 ). In conjunction with a capacitive SiC positive electrode in a quasi-solid-state PVA-KOH- p -nitroaniline (PVA-KOH-PNA) gel electrolyte, it resulted in a unique redox-active flexible solid-state asymmetric supercapacitor device. Due to the vigorous redox reactions of Fe 3 O 4 nanoparticles and the p -nitroaniline redox active electrolyte, the device delivers outstanding capacitive performance (specific capacitance of 97.6 F g −1 at 5 mV s −1 ) with maximum energy density of 48.94 Wh kg −1 at power density of 463.64 W kg −1 , surpassing many recently reported flexible supercapacitors. Therefore, these novel electrode materials with unique redox-active solid-state electrolytes may find promising applications in flexible energy storage devices.

Ni(OH)2 nanoparticles were decorated on mesoporous carbon spheres (MPCS) using a simple hard template method. The MPCS were derived from sodium carboxymethyl cellulose. As-prepared MPCS/Ni(OH)2 nanocomposites were used as electrode materials for supercapacitors. These composites exhibited better electrochemical properties than a pristine mesoporous carbon sphere owing to the synergistic effect. However, the increase in Ni(OH)2 is not proportional to the electrochemical performance improvement. The addition of an optimal amount of Ni(OH)2, typically 1:20 by weight (MPCS:NiCl2·6H2O), showed an excellent specific capacitance of 1338.296 F g−1 at a scan rate of 5 mV s−1. These encouraging results indicate excellent potential for the development of highly capacitive energy storage devices for practical applications.

MgCo 2 O 4 nanoneedles were deposited onto micro and mesoporous silicon carbide flakes (SiCF) to synthesize hybrid electrode materials with high capacitive performance for use as supercapacitors. These SiCF/MgCo 2 O 4 electrodes were fabricated at different MgCo 2 O 4 feeding ratios to determine the optimal MgCo 2 O 4 amount for both total surface area coverage and a suitable redox reaction rate by maximizing the synergy between the electric double layer capacitive effects of SiCF and the Faradic reaction of MgCo 2 O 4 nanoneedles. The SiCF/MgCo 2 O 4 electrode formed at a MgCo 2 O 4 /SiCF feeding ratio of 1.8:1 (SiCF/MgCo 2 O 4 (1.8)) had a specific surface area of 1069 m 2 g −1 . This surface featured the highest specific stored charge capacity of 310.02 C g -1 at a scan rate of 5 mV s -1 with 83.2% rate performance when the scan rate was increased from 5 to 500 mV s -1 in a 1 M KOH electrolyte. The outstanding electrochemical performance of the SiCF/MgCo 2 O 4 (1.8) electrode can be attributed to the ideal electrode material design, considering both the electric double-layer capacitive contribution of SiCF and the battery-type electrochemical behavior of the MgCo 2 O 4 nanoneedles on the SiCF surface. For high capacity electrode materials, this hybrid material strategy introduces possibilities for combinations of porous silicon carbide with other battery-type binary metal oxide materials.

This paper proposes a new control architecture for stable and transparent haptic rendering of interactive simulation involving a rigid tool and deformable objects. The traditional direct and proxy-based haptic rendering schemes are analyzed for the absolute stability, and transmit impedance employing the well-known bilateral control architecture frequently used in the field of teleoperation systems. An equivalent impedance is conveyed in the proposed control scheme to the haptic device instead of the contact force between the virtual tool and the object. The trade-off problem between the absolute stability and the transmitted impedance is resolved by computing the haptic feedback using the equivalent impedance. The proposed rendering scheme shows higher transparency than the conventional haptic rendering methods while maintaining the absolute stability.

Graphene/Co3O4 nanowire composite films were successfully synthesized using a simple, three-step treatment, and the effect of the Co3O4 nanowire content on the electrochemical properties of the composite films was studied. The one-dimensional Co3O4 nanowires were homogeneously embedded and dispersed between prepared graphene papers, forming a layered graphene/Co3O4 nanowire hybrid structure. These composite films exhibited better electrochemical properties than previously reported ones, such as graphene/CNT, where carbon spheres existed in the graphene composites, which were fabricated using the same method but without the Co3O4 nanowires. The addition of a small amount of Co3O4—typically 8 : 1 by weight (reduced graphene oxide (RGO) : Co3O4)—to form thick RGO/Co3O4 sandwiches in the form of papers resulted in an excellent specific charge capacity of 278.936 C g−1 at a scan rate of 5 mV s−1. These results indicate the potential of the composite for the development of highly capacitive energy storage devices for practical applications.

The aim of the current study was to establish animal scar models in a simple and rapid manner by comparing three methods. Wounds were created on the buttocks of Sprague Dawley rats. For Group 1, the initial wound was created by surgical incision. For Groups 2 and 3, a 1470-nm laser was employed to generate dermal burns as the initial wound. The wounds in Groups 1 and 3 were then sutured for three days. After the wound healing, Group 2 generated the largest collagen proportion with abundant collagen type I and significant increases in α-SMA and TGF-β1. The proposed method can be an efficient way to develop rat scar models in a simple manner for evaluating scar treatment.

Supercapacitors have been attracting significant research interest because of their wide range of applications in electric vehicles, digital devices, pulsing techniques due to their high power density, short charging time, and long cycling life. For ideal charge/discharge mechanism, the micro/mesoporous silicon carbide flakes (SiCFs) with a high surface area of about 1376 m2 g−1 were obtained by one-step carbonization of waste Si wafer without any chemical or physical activation. The micropores are derived from the partial evaporation of Si atoms during the carbonization process and mesopores are formed by the integration of neighboring micropores. Two-electrode supercapacitor cells constructed with this silicon carbide yielded high values of gravimetric capacitance and energy density with aqueous and organic electrolytes. SiCF electrode carbonized at 1250 °C shows a high-charge storage capacity, with a specific capacitance of 49.2 F g−1 in 1 M KCl aqueous electrolyte at a scan rate of 5 mV s−1 (specific capacitance for the single electrode : 196.8 F g−1). In addition, a specific capacitance of 38.7 F g−1 is measured in 1 M 1-butyl-3-methyl-imidazolium tetrafluoroborate in acetonitrile (BMIM BF4/AN) organic electrolyte at a scan rate of 5 mV s−1 (specific capacitance for the single electrode: 154.8 F g−1), with an energy density of 65.84 W h kg−1; and ∼98.65% specific capacitance being retained over 20,000 cycles.

Hierarchical micro/mesoporous silicon carbide flakes (SiCF) with a high surface area of about 1376 m 2 g −1 are obtained by one-step carbonization of waste Si wafer without any chemical or physical activation. The micropores are derived from the partial evaporation of Si atoms during the carbonization process and mesopores are formed by the integration of neighboring micropores. During carbonization process, the proportion of micro and mesopores in SiCF can be controlled by carbonization time by controlling the amount of partial evaporation of Si atoms. The SiCF electrode carbonized for 8 h at 1250 °C exhibits high charge storage capacity with a specific capacitance of 203.7 F g −1 at a scan rate of 5 mV s −1 with 87.3% rate performance from 5 to 500 mV s −1 in 1 M KCl aqueous electrolyte. The outstanding electrochemical performance can be the synergistic effect of both enhanced electric double layer properties caused by micropores and reduced resistant pathways for ions diffusion in the pores as well as a large accessible surface area for ion transport/charge storage caused by mesopores. These encouraging results demonstrate that the SiCF carbonized for 8 h at 1250 °C can be promising candidate for high performance electrode materials for supercapacitors.

Three-dimensional silicon carbide-based frameworks with hierarchical micro- and mesoporous structures (2MSiC) are prepared by employing the template method and carbonization reaction using aerosol-spray drying. The mesopores are generated by the self-assembly of a structure-directing agent, whereas the micropores originate from the partial evaporation of Si atoms during the carbonization process. During the carbonization process, the proportion of micro- and mesopores in 2MSiC can be controlled by the carbonization temperature by controlling the amount of partial evaporation of Si atoms. The 2MSiC electrode prepared using a Brij56 structure-directing agent as the mesopore template and carbonized at 1250 °C exhibits a high charge storage capacity with a specific capacitance of 259.9 F g −1 at a scan rate of 5 mV s −1 with 88.1% rate performance from 5 to 500 mV s −1 in 1 M KCl aqueous electrolyte. This outstanding electrochemical performance can be attributed to the synergistic effect of both the enhanced electric double layer properties caused by micropores and reduced resistant pathways for ion diffusion in the pores as well as a large accessible surface area for ion transport/charge storage caused by mesopores. These encouraging results demonstrate that the 2MSiC electrode prepared with Brij56 and carbonized at 1250 °C is a promising candidate for high-performance electrode materials for supercapacitors.