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The progress in flexible and neuromorphic electronics technologies has facilitated the development of artificial perception systems. By closely emulating biological functions, these systems are at the forefront of revolutionizing intelligent robotics and refining the dynamics of human–machine interactions. Among these, tactile sensory neuromorphic technologies stand out for their ability to replicate the intricate architecture and processing mechanisms of the brain. This replication not only facilitates remarkable computational efficiency but also equips devices with efficient real-time data-processing capability, which is a cornerstone in artificial intelligence evolution and human–machine interface enhancement. Herein, we highlight recent advancements in neuromorphic systems designed to mimic the functionalities of the human tactile sensory system, a critical component of somatosensory functions. After discussing the tactile sensors which biomimic the mechanoreceptors, insights are provided to integrate artificial synapses and neural networks for advanced information recognition emphasizing the efficiency and sophistication of integrated system. It showcases the evolution of tactile recognition biomimicry, extending beyond replicating the physical properties of human skin to biomimicking tactile sensations and efferent/afferent nerve functions. These developments demonstrate significant potential for creating sensitive, adaptive, plastic, and memory-capable devices for human-centric applications. Moreover, this review addresses the impact of skin-related diseases on tactile perception and the research toward developing artificial skin to mimic sensory and motor functions, aiming to restore tactile reception for perceptual challenged individuals. It concludes with an overview of state-of-the-art biomimetic artificial tactile systems based on the manufacturing–structure–property–performance relationships, from devices mimicking mechanoreceptor functions to integrated systems, underscoring the promising future of artificial tactile sensing and neuromorphic device innovation. [ABSTRACT FROM AUTHOR]

We validated a Korean version of the Broad Autism Phenotype Questionnaire (BAPQ) by investigating its factor structure with a nonclinical sample. Participants were 495 undergraduate students in Korea. The results show that the Korean version of the BAPQ (K-BAPQ) had adequate internal consistency (Cronbach's α =.75–.89). Correlations between scores on the BAPQ and on the Autism-Spectrum Quotient were statistically significant and moderate-to-high in size. Confirmatory factor analysis did not show a satisfactory fit with the factor structure of the original BAPQ. Exploratory factor analysis demonstrated that a three-factor structure could be suitable in our sample, but the internal structure of the BAPQ still needs further examination. We recommend use of the total score of the K-BAPQ, as opposed to those of the subscales alone, and suggest that further research is needed to confirm the factor structure. [ABSTRACT FROM AUTHOR]

The effect of polar and non-polar solvent combinations on a high moisture barrier coating film composed of an epoxy–acrylate hybrid resin was determined with the aim of promoting its application in flexible device applications. More specifically, the epoxy–acrylate hybrid resin was formulated using various solvent combinations and was manufactured via ultraviolet (UV) and thermal curing. An outstanding barrier performance and excellent thermal and mechanical properties were observed when the resin was prepared using solvents with a small gap between their solubility parameters and at high vapor pressures. This was attributed to an increase in the polymerization degree of the epoxy resin in the absence of residual solvent. In addition, the water vapor transmission rate (WVTR) of a polyethylene terephthalate (PET)/polymer/SiNx multi-layered film was also influenced by the solvent employed for the coating solution, wherein a combination of acetone/toluene was optimal. This solvent system possessed a small solubility gap (i.e., 0.057), resulting in a WVTR of 1.17 × 10−2 g/m2·d after the deposition of a 50 nm layer of SiNx. Notably, this WVTR is >2-fold lower than that obtained for the ethanol/toluene combination with a large solubility constant difference > 5.0. These findings highlight the importance of the polymer coating solution composition in the preparation of multi-layer architectures to obtain effective inorganic barrier coatings. [Display omitted] • The solvent effect was observed in a high moisture barrier coating film Epoxy–acrylate hybrid resin films were coated on PET and cured • An excellent barrier performance + good thermal/mechanical properties were observed • The optimal solvent system gave an excellent WVTR of 1.17 × 10−2 g/m2∙d [ABSTRACT FROM AUTHOR]

An efficient strategy for the visible‐light‐promoted intramolecular C─O bond formation has been accomplished, which allows the synthesis of cyclic ether derivatives in the absence of a photocatalyst. This reaction is likely to occur through the generation of alkoxy radical from in situ generated O─I bond, followed by 1,5‐hydrogen atom transfer (1,5‐HAT) and subsequent intramolecular cyclization to form a C─O bond. This synthetic approach offers an efficient tool by providing access to valuable cyclic ether scaffolds under mild reaction conditions. [ABSTRACT FROM AUTHOR]

This paper presents a remote testbed for metallic fuel fabrication using surrogates or depleted uranium. The testbed named "remote fuel fabrication mock-up (RFFM)" was created at the Korea Atomic Energy Research Institute and specifically designed to incorporate remote operation and maintenance. The subsystems of the RFFM are described, and test results regarding remotely conducted metallic fuel slug fabrication at the RFFM are also presented. After fabricating fuel slugs using copper ingots, their specifications and properties were analyzed and evaluated using chemical analysis, radiographic tests, and diameter and weight measurements. Analysis results showed that the fabricated metallic fuel slugs have an acceptance rate of more than 90% and a casting ratio (ratio of weight of injected metal to charged metal) of more than 0.7. Moreover, operations involving remote handling of in-cell equipment were also satisfactory. [ABSTRACT FROM AUTHOR]

This paper presents a remote testbed for metallic fuel fabrication using surrogates or depleted uranium. The testbed named "remote fuel fabrication mock-up (RFFM)" was created at the Korea Atomic Energy Research Institute and specifically designed to incorporate remote operation and maintenance. The subsystems of the RFFM are described, and test results regarding remotely conducted metallic fuel slug fabrication at the RFFM are also presented. After fabricating fuel slugs using copper ingots, their specifications and properties were analyzed and evaluated using chemical analysis, radiographic tests, and diameter and weight measurements. Analysis results showed that the fabricated metallic fuel slugs have an acceptance rate of more than 90% and a casting ratio (ratio of weight of injected metal to charged metal) of more than 0.7. Moreover, operations involving remote handling of in-cell equipment were also satisfactory. [ABSTRACT FROM AUTHOR]

Abstract A super-engineering-plastic polyphenylene sulfide (PPS)-based composite was fabricated for circuit board application. A small amount of liquid crystal polymer (LCP) was blended with PPS in order to enhance the copper plating performance. In addition, 8 wt% of laser activated particles (LAPs) were added to the polymer blend. LCP/LAP exhibited a better interfacial affinity than that of PPS/LAP. A weakly layered structure was observed for the PPS–LCP blend due to flowability difference of two polymers; LCP was flow to surface during injection molding. These layered structure and interfacial affinity difference led the LAP leaning, a small number of LAPs were observed at the PPS dominant region, while a larger amount was observed at the LCP dominant region. Moreover, the mechanical property, circuit building speed and adhesion of copper circuit also improved after the LCP blend. Therefore, laser direct structuring and electroless plating applicable PPS composite was fabricated vis LCP blend. [ABSTRACT FROM AUTHOR]

A composite of laser-activate particles and the super engineering plastic of polyphenylene sulfide was fabricated via melt-mixing. The laser-activate particle surfaces were modified using hydroperoxide and three different silane coupling agents. The laser-activate particles dramatically deteriorate the mechanical properties of polyphenylene sulfide because of its low compatibility with the polymer. However, surface modification, especially via amino silane treatment, effectively prevented the degradation of thermal and mechanical properties upon adding laser-activate particle, while modification with phenyl silane had the reverse effect. In order to confirm the different effects, solubility parameters obtained by theoretical calculation via the group contribution method were compared. Thermally and mechanically enhanced laser-activate particle/polyphenylene sulfide composites were fabricated for laser direct structuring and electroless plating applications. [ABSTRACT FROM AUTHOR]

Thermal conductive composites were fabricated using a boron nitride (BN) filler and polyethylene naphthalate (PEN) matrix. To enhance the interfacial affinity, two types of silane curing agents, 3‐aminopropyl triethoxysilane (APTES) and phenyl triethoxysilane (PTEOS), were introduced onto the BN particle surfaces. The modified BN particles were embedded in a PEN matrix via a melt mixing process using twin extrusion to form APTES@BN and PTEOS@BN composites. The highest thermal conductivity was exhibited at 50 wt% BN (1.41 W/mK), which increased to 1.54 W/mK and 1.63 W/mK when the BN particles were surface treated. These values were 9% and 16% higher than the thermal conductivities of the pure BN and the PEN matrix, respectively. The surface‐treated composite also showed improved storage moduli and tensile strength because of the improved interfacial adhesion and the interaction between the BN filler and the PEN matrix. POLYM. COMPOS., 39:E1692–E1700, 2018. © 2017 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Herein, we describe the fabrication of thermally conductive composites based on an epoxy matrix with a hybrid filler of hexagonal boron nitride (h-BN) and multi-walled carbon nanotubes (MWCNTs) via the wetting method. The h-BN particles were exfoliated to boron nitride nanosheets (BNNSs) by heating in a tubular furnace with steam and sonication. The h-BN particles in the composite were densely packed and oriented almost perpendicular to the bottom. On the other hand, the BNNSs were more loosely packed and randomly oriented, and exhibited higher through-plane thermal conductivity despite the low filler content. After the incorporation of MWCNTs, the filler thermal conductivities of both the composites significantly increased. In particular, 9 wt% of MWCNTs was sufficient to increase the thermal conductivity of the BNNS composite from 3.12 to 4.25 W m −1 K −1 because of the intercalation of the nanotubes between the BNNSs, which provided a three-dimensional heat flow path. Moreover, the MWCNTs interrupted the dense particle packing and the filler concentration was reduced from 56.7 to 43.8 wt%. In the case of h-BN composite, this effect was relatively weak because the nanotubes were agglomerated between the micron-sized BN particles. [ABSTRACT FROM AUTHOR]

IV–VI-group Sn–chalcogenide-based nanomaterials have attracted interest in various research fields because they offer unique characteristics distinct from their bulk counterparts. The introduction of pores can manipulate the electrical and thermal transport characteristics of the material, which is considered a promising strategy to improve the thermoelectric properties. Herein, we report on the successful fabrication and optimization of porous SnSeS-based nanosheets and their thermoelectric enhancement. Two-dimensional SnSe 0.8 S 0.2 (SnSeS) nanocrystals are chemically exfoliated from a layered bulk structure through a Li-intercalation and exfoliation process. Many pores are successfully introduced to the SnSeS nanosheets by solution-phase chemical transformation, and the porosity of the materials is optimized by manipulating the reaction time, resulting in the effective reduction of the thermal conductivity and enhancement of the thermoelectric performance. The incorporation of nanoscale and porous structure can accelerate research advances regarding nanoscale porous materials and high-performance thermoelectrics. [ABSTRACT FROM AUTHOR]

A thermally conductive composite was fabricated using a BN filler and an epoxy matrix. Because of electrostatic repulsion force, the BN/epoxy composite had poor interfacial affinity, which led to a decrease in the thermal conductivity. To enhance the interfacial affinity, pre-ceramic polysilazane (PSZ) was introduced onto the BN surface and it was sintered in various conditions. PSZ was converted to different structure depended on pyrolysis conditions. After the pyrolysis, the PSZ was converted into a SiOC ceramic in nitrogen atmosphere, and to SiO 2 and ash in air atmosphere. The thermal conductivity of the BN-PSZ/epoxy composite decreased as the pyrolysis temperature was increased because of the decomposition of polar functional groups. Pyrolysis at 300 °C in nitrogen atmosphere yielded the highest performance, resulting in an increase in the thermal conductivity to 3.521 W m −1 K −1 at 70 wt% of filler, which was a 1.35-fold increase compared with the raw BN/epoxy composite. [ABSTRACT FROM AUTHOR]

Irradiation of 9-ester-substituted anthracenes with visible light results in the formation of endoperoxides in the absence of a photocatalyst, which further undergo base-assisted fragmentation to afford anthraquinones. The excited state species of anthracene generated by energy transfer, interacts with 3O2 to afford 1O2 by energy transfer and undergoes cycloaddition with 1O2. By employing palladium(II)-catalyzed and visible light-mediated transformations, we have developed an efficient synthetic protocol for accessing diverse anthraquinones from readily available diaryl carboxylic acids. The optimal result was obtained with palladium(II) acetate, Ac-Ile-OH, benzoquinone and potassium carbonate in tert-amyl alcohol under O2 at 90 °C with irradiation from a 30 W fluorescent light bulb. [ABSTRACT FROM AUTHOR]

In this work, the waste metal sludge was used to thermal thermally conductive filler after sintering and pulverization. The thermal conductivity of a composite containing metal sludge is only 0.93 W m −1 K −1 for 60 wt% of filler, which is lower than that of conventional thermally conductive composites containing ceramic fillers at the same filler weight fraction. However, the differences between the thermal conductivity values of the filler materials are reduced when compared at the same volume fraction, due to the high density of the metal filler. Moreover, the thermal conductivity values were similar after surface modification of the filler particles using a silane coupling agent. Hence, the surface modification of metal oxide particles from sludge wastes is a promising method for producing a filler material with reasonable thermal conductivity values compared to conventional ceramic fillers. In addition, this method contributes to reducing an environmental pollution and the production costs of various electronic devices. [ABSTRACT FROM AUTHOR]

In this study, thermally conductive composite was fabricated using hexagonal and spherically aggregated boron nitride filler based on epoxy and polyphenylene sulfide (PPS) matrixes. The spherically aggregated BN (A-BN) particles were shown the outstanding thermal conductivity compared hexagonal BN (H-BN) in the epoxy matrix. However, A-BN is very weak to external forces and broken during PPS based melt processing, causing it to lose the advantage of its particulate shape. Therefore, we adopted a particle coating method for the A-BN to enhance its durability, using pre-ceramic polysilazane (PSZ) in solution. With the PSZ coating of A-BN, the spherical particle shape was retained after melt mixing. Moreover, the interfacial affinity between BN and PPS was enhanced by secondary interactions between the polar functional groups comprising PSZ, thereby increasing the through-plane thermal conductivity from 1.82 to 3.9 W m −1 K −1 at 70 wt% of A-BN filler, because the spherical filler particles formed a three-dimensional heat flow path. [ABSTRACT FROM AUTHOR]

BN/PPS core-shell structured pellet and its composite film were primarily fabricated via a particle coating method using an adhesive layer. A thermally conductive composite was fabricated using BN-coated PPS by hot pressing. The core-shell structure did not collapse after hot pressing and formed a well-connected particle chain. Moreover, the BN/PPS composite prepared using the proposed method has a higher thermal conductivity compared to the conventional composite fabrication method, melt mixing and powder mixing, at the same filler concentration because the connected particle chain acts as a continuous heat flow channel. Moreover, the thickness of the particle layer can be controlled by controlling the viscosity of the adhesive epoxy layer using acetone as the solvent. We fabricated BN/PPS pellets with various BN layer thickness. A 1:0.3 wt ratio of epoxy and acetone has the highest thermal conductivity enhancement ratio compared to the melt mixed composite. We fabricated a composite using the hybrid method; the polymer core was prepared via melt mixing and the BN particles were coated on this core. The BN particle in the core and the outer layer has a synergetic effect, forming a 3-dimensional heat flow path, leading to outstanding thermal conductivity with a only small amount of filler. [ABSTRACT FROM AUTHOR]

Polyphenylene sulfide (PPS) is a promising material as an important engineering thermoplastic polymer for various industrial applications. Here we report a highly thermally conductive PPS composite containing boron nitride (BN) and multiwalled carbon nanotubes (MWCNTs) as a thermally conductive filler. The composite was prepared by the particle coating method into polymer pellets in order to obtain high thermal conductivity with low filler concentration, and thus overcome the drawbacks of melt mixing. A comparison between conventional melt mixing and the proposed method showed that the continuous connection of particles at the surface of each pellet led to great enhancement of thermal conductivity. Moreover, the electrically insulating BN layer effectively interrupted electron conduction, which is the major problem with using MWCNTs as a thermally conductive filler, despite their superior thermal conductivity. Our results show that the particle coating method may be used as a promising composite fabrication method for engineering plastics-based thermally conductive materials. [ABSTRACT FROM AUTHOR]

A straightforward synthetic strategy for generating useful anthracene derivatives was developed involving palladium(II)-catalyzed tandem transformation with carboxylic acids as traceless directing groups. Carboxyl-directed C-H alkenylation, carboxyl-directed secondary C-H activation and rollover, intramolecular C−C bond formation, and decarboxylative aromatization are proposed as the key steps in the tandem reaction pathway. This novel synthetic route utilizes a broad range of substrates and provides a convenient synthetic tool that allows access to acenes. [ABSTRACT FROM AUTHOR]

A straightforward synthetic strategy for generating useful anthracene derivatives was developed involving palladium(II)-catalyzed tandem transformation with carboxylic acids as traceless directing groups. Carboxyl-directed C-H alkenylation, carboxyl-directed secondary C-H activation and rollover, intramolecular C−C bond formation, and decarboxylative aromatization are proposed as the key steps in the tandem reaction pathway. This novel synthetic route utilizes a broad range of substrates and provides a convenient synthetic tool that allows access to acenes. [ABSTRACT FROM AUTHOR]

We report magnetic alignment of aluminum nitride (AlN) platelets and the outstanding material properties of its polymer composite. The magnetic property of AlN was produced by decorating the surface with strong paramagnetic iron oxide (Fe 3 O 4 ) nanospheres; the amount of iron oxide deposited is easily controlled by modulating the precursors. With the aid of iron oxide nanospheres, randomly dispersed two dimensional AlN in an epoxy matrix are successfully re-arranged in the vertical direction of the film plane by applying an external magnetic field during epoxy heat curing. Vertically aligned AlN effectively generate thermal transport channels and enhance thermal conductivity from 0.915 W/mK to 1.754 W/mK with 20 vol% filler loading which is a 1.92-fold increase at the low filler concentration compared with randomly oriented composites. The filler alignment will be a promising candidate for thermal interface material fabrication which not only significantly improves the performance, but also prevents the mechanical property degradation caused by extremely high filler loading. [ABSTRACT FROM AUTHOR]

A composite with high thermal conductivity was fabricated using anisotropic boron nitride (BN) and particle alignment techniques. Iron oxide nanoparticles introduced onto the BN surface acted as magnets that gave rise to effective particle alignment. Because of the weak interfacial affinity between filler and matrix, particles chipped during the process and the post-alignment composite had poor morphology. In order to enhance attraction at the interface, the particle surface was modified using a silane coupling agent and poly(tetramethylene glycol). The long carbon chain in the outer polymer layer became entangled with that of the epoxy matrix, resulting in enhancement of interfacial affinity and thermal conductivity. The thermal conductivity of the synthesized composite increased from 0.832 to 1.448 on 20 vol% of filler loading after particle orientation, and increased to 1.577 W/mK after polyol coating. These particle alignment and surface modifications suggest promising applications in the development of thermal interface materials. [ABSTRACT FROM AUTHOR]

In this study, anisotropic boron nitride (BN) was vertically aligned along the direction of heat transport using an external electric field. A titanium oxide (TiO 2 ) nanoparticle, which has a superior dielectric property, was deposited onto the BN surface to act as an electrically responsive material that allowed for particle alignment. Because of the relatively low dielectric property of BN, it was not observed morphological change under the electric field. After the surface modification using titanium oxide, the polarization of highly dielectric titanium oxide in the electric field led to the formation of vertical particle arrangements. The through-plane thermal conductivity of the synthesized vertically aligned composite increased from 0.78 W m −1 K −1 to 1.54 W m −1 K −1 , while through-plane thermal conductivity was decreased 1.17 W m −1 K −1 to 0.84 W m −1 K −1 , with 20 vol% filler loading. This is a 1.9-fold increase and 0.72-fold reduction compared with the conductivity of a randomly oriented composite. Moreover, this vertically aligned filler composite exhibits better mechanical properties based on the same thermal conductivity. [ABSTRACT FROM AUTHOR]

Thermally conductive BN/SiC binary filler and epoxy composite materials were fabricated via magnetic alignment. The magnetic iron oxide particles on the surface of the filler allowed particle re-orientation under the external magnetic field. Owing to its anisotropy, the vertically aligned BN composite had a high thermal conductivity and generated a vertical heat flow path. When the SiC nanoparticles were added to the binary filler, they hindered BN-particle aggregation and led to the formation of a three-dimensional heat conduction path, thereby resulting in increased thermal conductivity. The maximum thermal conductivity (5.77 W/mK) was obtained with an addition of SiC filler, and was 3.08-fold and 1.1-fold higher than that of randomly mixed BN and vertically aligned BN composites, respectively. The additional SiC–Fe 3 O 4 particles resulted in significant aggregation of the filler, which in turn led to a decrease in the thermal conductivity. The measured storage modulus of the BN–Fe 3 O 4 /SiC binary filler composite was also higher than those of the BN–Fe 3 O 4 and BN–Fe 3 O 4 /SiC–Fe 3 O 4 composites, owing to the aggregation of particles. [ABSTRACT FROM AUTHOR]

Anisotropic boron nitride (BN) was vertically aligned along the direction of heat transport using a magnetic field. Iron oxide nanoparticles deposited onto the BN surface act as a magnetically responsive material allowing particle alignment. The amount of iron oxide deposited, and therefore the magnetic response, is easily controlled by modulating the precursors. The polarization of paramagnetic iron oxide in the magnetic field leads to the formation of vertical particle arrangements. The thermal conductivity of the synthesized vertically aligned composite increased from 1.765 W m −1 K −1 to 3.445 W m −1 K −1 with 30 vol% filler loading that is a 1.96-fold increase compared with a randomly oriented composite. The filler content affected both particle dispersion and arrangements, with homogeneously dispersed fillers aggregating due to induced dipole interactions into column-like structures with favorable thermal transport properties. [ABSTRACT FROM AUTHOR]

According to the New Look theory, size perception is affected by emotional factors. Although previous studies have attempted to explain the effects of both emotion and motivation on size perception, they have failed to identify the underlying mechanisms. This study aimed to investigate the underlying mechanisms of size perception by applying attention toward facial expressions using the Ebbinghaus illusion as a measurement tool. The participants, female university students, were asked to judge the size of a target stimulus relative to the size of facial expressions (i.e., happy, angry, and neutral) surrounding the target. The results revealed that the participants perceived angry and neutral faces to be larger than happy faces. This finding indicates that individuals pay closer attention to neutral and angry faces than happy ones. These results suggest that the mechanisms underlying size perception involve cognitive processes that focus attention toward relevant stimuli and block out irrelevant stimuli. [ABSTRACT FROM AUTHOR]

The aim of the present study was to use an eye-tracking device to investigate attention bias and its mechanism toward high-calorie virtual food in individuals with bulimic tendencies (BT). A total of 76 participants were divided into two groups: a BT group ( n = 38) and a control group ( n = 38). The eye movements of all participants were continuously measured while the participants were confronted with pairs of high-calorie, low-calorie, and nonfood virtual stimuli (pictures). It was found that the BT group detected high-calorie food more quickly than they did the low-calorie food and nonfood stimuli, but they also avoided the high-calorie food. These results indicate that individuals with BT automatically allocate their attention toward high-calorie food and, subsequently, try to avoid it. Based on these results, we suggest that this approach-avoidance pattern for high-calorie virtual food could be a factor in the development and maintenance of bulimia symptoms by encouraging individuals with BT to be in conflict with the urge to overeat. [ABSTRACT FROM AUTHOR]

We fabricated vertically aligned silicon carbide (SiC)/epoxy composites along the direction of heat transport using a magnetic field. SiC was made magnetically responsive by introduction of strong paramagnetic iron oxide (Fe 3 O 4 ) nanospheres, and the amount of iron oxide deposited is easily controlled by modulating the precursors. Fe 3 O 4 -coated SiC filler was vertically aligned by an external magnetic field and generated particle columns. These columns act as a superior thermal conducting path. The thermal conductivity of the synthesized vertically aligned composite increased from 0.945 W m −1 K −1 to 1.681 W m −1 K −1 with 20 vol% filler loading that is a 1.78-fold increase compared with the randomly dispersed filler composite. Moreover, the electrical conductivity of SiC, which is a major drawback, was also controlled by the electrically insulating iron oxide coating. These results suggest promising applications of magnetically aligned SiC-based polymer composites in thermal interface materials. [ABSTRACT FROM AUTHOR]

Copper nanowire particles were synthesized by reducing Cu(NO 3 ) 2 with hydrazine, and copper nanowire/epoxy composites were prepared for use as thermal interface materials. The surfaces of the copper nanowire particles were coated with TiO 2 to enhance the mechanical and thermal properties in the polymer matrix. The TiO 2 -coated copper nanowire/epoxy composites exhibited thermal conductivities ranging from 0.2 to 1.1248 W/m K, values that are higher than those of raw copper nanowire/epoxy composites at the same weight fraction. The effects of the TiO 2 -coated copper nanowire were investigated through various thermal conductivity prediction models. In addition, the TiO 2 -coated copper nanowire composites showed decreased electrical conductivity as compared with raw copper nanowire composites. Thus, the TiO 2 -coated copper nanowire composites prepared in the present work could prove to be desirable as thermal interface materials in the electronics industry. [ABSTRACT FROM AUTHOR]

The ceramic/polymer composites based on epoxy-terminated dimethylsiloxane (ETDS) and boron nitride (BN) were prepared for use as thermal interface materials (TIMs). 250 µm-sized BN was used as a filler to achieve high-thermal-conductivity composites. To improve the interfacial adhesion between the BN particles and the ETDS matrix, the surface of BN particles were modified with silica via the sol–gel method with tetraethyl orthosilicate (TEOS). The interfacial adhesion properties of the composites were determined by the surface free energy of the particles using a contact angle test. The surface-modified BN/ETDS composites exhibited thermal conductivities ranging from 0.2 W/m K to 3.1 W/m K, exceeding those of raw BN/ETDS composites at the same weight fractions. Agari׳s model was used to analyze the measured thermal conductivity as a function of the SiO 2 -BN concentration. Moreover, the storage modulus of the BN/ETDS composites was found to increase with surface modification of the BN particles. [ABSTRACT FROM AUTHOR]

The surface-treated boron nitride (BN) particles are prepared with polysilazane (PSZ) by using a dip-coating method to fabricate a thermally conductive interface material. PSZ-BN particles are generated by crosslinking of PSZ on BN and heat treatment of the formed PSZ-BN at 700 °C to convert PSZ-BN to SiCNO-BN. The SiCNO-BN particles are fabricated with Nylon 6,6 by using an extruder and injection molding method. The interfacial adhesion between the BN particles and the Nylon 6,6 matrix is enhanced by surface treatment of the BN particles. The surface-treated BN/Nylon 6,6 composites exhibit thermal conductivity ranging from 0.3270 to 0.4230 W/m K (through-plane) and 1.6510 to 4.960 W/m K (in-plane), which is higher than that in the case of loading with pristine BN/Nylon 6,6 composites at the same weight fraction. The tensile strength and tensile modulus increase from 59.13 and 1.67 GPa with the use of pristine BN to 69.15 and 2.10 GPa with incorporation of SiCNO-BN into the Nylon 6,6 composite. [ABSTRACT FROM AUTHOR]

Heat dissipation is an important factor in maintaining solar cell module efficiency and in preventing thermal degradation of polymers within the cells. Aluminum nitride (AlN) and boron nitride (BN), surface-modified via a silane coupling agent, were used as a thermal conducting filler in conjunction with a poly(vinylidene fluoride) (PVDF) matrix with high thermal conductivity for the backsheet of the solar cell. The composites with 70 wt% and a 2:8 AlN/BN ratio showed a maximum thermal conductivity of 5.85 W m −1 K −1 ), which is 31 times larger than a pure PVDF matrix. The storage modulus was almost comparable to that of polyethylene terephthalate (PET), which is normally used to provide hardness for the PVDF. The water swelling ratio was reduced by addition of the filler, and the thermal and mechanical properties after swelling and drying were not degraded. The fabricated ceramic filler contained PVDF composite, satisfying the thermal and mechanical properties and long-term stability for a mono-layer structure for the backsheet of a solar cell. [ABSTRACT FROM AUTHOR]

This study aimed to examine the effects of arousal and expectation on eyewitness memory. We exposed 97 participants to an immersive eyewitness experience by creating four virtual reality stimulus environments. The participants were randomly assigned to one of four conditions: arousing and expected, arousing and unexpected, nonarousing and expected, and nonarousing and unexpected. The results revealed that memory performance for an arousing encounter was significantly lower than that for a nonarousing encounter, and that memory performance for an unexpected environment was significantly lower compared with an expected one. In addition, memory performance was lowest in the condition that was both arousing and unexpected. No interaction between arousal and expectation was found. [ABSTRACT FROM AUTHOR]

This study aims to investigate packaging materials based on polymer matrices for microelectronics. A binary filler system consisting of whiskers and aggregated particles of boron nitride (BN) was employed to improve the thermal conductivity of the epoxy resin. To prevent filler breakage during commercial mechanical mixing, a wetting method was used during sample fabrication. The polar functionalities introduced on the BN particles by sodium hydroxide treatment allowed the permeation of the epoxy resin because of a secondary interaction, which allowed the fabrication of a composite without voids. The maximized filler packing density and filler dispersion of the two kinds of fillers caused changes in the thermal conductivity. According to our results, the composite containing a 70:30 volume percent of the filler fraction of aggregated and whisker-type BN particles showed the maximum thermal conductivity. This is ascribed to the maximized formation of conductive networks combined with minimization of the heat resistance along the heat flow path. The filler composition and shape also resulted in composites with a higher storage modulus. [ABSTRACT FROM AUTHOR]

Abstract: UV-curable polyurethane acrylate (PUA) is currently used as an encapsulant for undersea sonar devices, and new, desirable polymeric materials should have lower swelling ratios when in contact with seawater and paraffin oil, along with better mechanical strength, when compared to PUA after impregnation. We blended PUA with boron nitride (BN) to fabricate these desirable composites for sonar encapsulants. PUA-coated BN was prepared and was found to have better interfacial adhesion between the PUA matrix and the BN filler. The surface-modified filler showed enhanced dispersibility and affinity due to the surface treatment with functional groups that affected the surface free energy and the structural similarity of the doped crystallized diisocyanate molecule in the matrix. Studies of these composites showed that the swelling ratios decreased with increasing BN–PUA content. The tensile strength of the BN–PUA/PUA composite in either seawater or paraffin was higher than that of the BN/PUA composite as the immersion time increased. We conclude that these composites are promising materials for use as sonar encapsulants and can significantly improve both mechanical strength and long term stability. [Copyright &y& Elsevier]

Abstract: Boron nitride (BN) particles fabricated with different surface treatments were used to prepare thermally conductive polymer composites by epoxy wetting. The polar functionality present on the BN particles allowed the permeation of the epoxy resin because of a secondary interaction, which allowed the fabrication of a composite containing high filler concentration. The different cohesive energy densities of the synthesized material due to a functional-group-induced surface treatment effect on surface free energy and wettability determined the thermal and mechanical properties of the polymer. The results indicate that surface-curing agents interrupt the interaction between the filler and matrix, and do not always enhance thermal conductivity. Moreover, the composites showed maximum thermal conductivity at 30wt% epoxy loading when the fixed-pore volume fraction reached in the filtrated BN film. The measured storage modulus was also enhanced by surface treatment because of the sufficient interface produced and interaction between the large amount of the filler and epoxy. [Copyright &y& Elsevier]

Abstract: The thermal conductivities of composites with an epoxy-terminated dimethylsiloxane (ETDS) matrix and boron nitride (BN) powder fillers were investigated. Two surface curing agents, 3-glycidoxypropyltrimethoxysilane (KBM-403) and 3-chloropropyltrimethoxysilane (KBM-703), were doped onto the surfaces of hydroxyl-functionalized boron nitride using a simple sol–gel process to act as fillers in the thermally conducting composites. These synthesized materials were embedded in epoxy resin via a solvent casting method. The surface modification had an appreciable effect on the thermal conductivity resulting in increased thermal conductivity up to 70wt%. The thermal conductivities of the composites containing 70wt% BN particles treated with the KBM-403 and KBM-703 curing agents were 4.11 and 3.88W/mK, respectively, compared to 2.92W/mK for the composite without surface treatment. [Copyright &y& Elsevier]

Despite first being described from Virginia, the widely distributed brackish water hydrozoan Blackfordia virginica is often hypothesized to have been introduced from the Black Sea to the United States. However, the alternative view that B. virginica was introduced to the Black Sea also persists in the literature. This study investigates the population structure of B. virginica in the United States to assess the directionality and/or the number of introduction events. During 2009 and 2010, estuaries were sampled from Delaware to Louisiana for brackish water hydromedusae. Nineteen samples of Blackfordia virginica were collected from four localities, including a channel running between St. Catherines Island and Lake Pontchartrain, Louisiana, a region for which it had not been reported prior to this study. We PCR amplified and sequenced two mitochondrial markers (COI & 16S), and one nuclear marker (ITS1). We compared data from individuals collected on the east coast of the United States with individuals collected in California. This revealed low diversity (two haplotypes with a maximal p-difference of 0.03% for COI and just a single haplotype for 16S) and no unique haplotypes at any locality. Low genetic variability, shared haplotypes in disparate localities, and a lack of unique haplotypes in any population are consistent with a founder effect, suggesting a single introduction and subsequent spread throughout the United States. [ABSTRACT FROM AUTHOR]

Abstract: A modeling and simulation methodology was proposed in order to implement the dynamic material flow of the pyroprocess. Since the static mass balance provides the limited information on the material flow, it is hard to predict dynamic behavior according to event. Therefore, a discrete event system (DES)-based model named, PyroFlow, was developed at the Korea Atomic Energy Research Institute (KAERI). PyroFlow is able to calculate dynamic mass balance and also show various dynamic operational results in real time. By using PyroFlow, it is easy to rapidly predict unforeseeable results, such as throughput in unit process, accumulated product in buffer and operation status. As preliminary simulations, bottleneck analyses in the pyroprocess were carried out and consequently it was presented that operation strategy had influence on the productivity of the pyroprocess. [ABSTRACT FROM AUTHOR]

Drivers of disease cycles are poorly understood in marine ecosystems in spite of increasing outbreaks. We monitored a newly emerged fungal epizootic (aspergillosis) affecting sea fan corals (Gorgonia ventalina L.) in the Florida Keys to evaluate causes of its rise and fall over 6 years. Since August 1997, aspergillosis has nearly eradicated large sea fans at some sites. However, sea fan densities have remained relatively constant due to episodic recruitment replacing large fans with small. Recruitment itself was affected by infection and occurred only when prevalence of disease was low. This impact on recruitment occurred because the largest, potentially most fecund colonies had the highest prevalence of disease, and the pathogen significantly suppressed reproduction of infected fans. Moreover, high mortality among adults resulted in a demographic shift to smaller colonies. The most dramatic impact of aspergillosis was the Keys-wide loss of >50% of sea fan tissue from complete and partial mortality. Aspergillosis prevalence has declined steadily over the last 6 years, and we consider the following hypotheses for decline of the epizootic: change in environment, change in pathogen input, and increase in host resistance. We conclude that increasing host resistance is the most likely driver of the decline. However, a change in any of a number of factors, for example, recruitment of naïve hosts, rate of pathogen input, or environmental conditions (water quality and temperature), is likely to promote reemergence of the epizootic. [ABSTRACT FROM AUTHOR]

Box & Hunter (1957) recommended a set of orthogonally blocked central composite designs (CCD) when the region of interest is spherical. In order to achieve rotatability along with orthogonal blocking, the block size for those designs becomes unequal and it may not be attractive or practical to use such unequally blocked designs in many practical situations. In this paper, a construction method of orthogonally blocked CCD under the assumption of equal block size is proposed and an index of block orthogonality is introduced. [ABSTRACT FROM AUTHOR]

As the marine industry develops, the importance of seawater treatment process is increasing. To treat seawater, oxidation processes have primarily been used, such as ballast water treatment systems, aquaculture farm operations, aquarium management, and seawater desalination. However, dissolved organic matter in seawater, whose characteristics vary spatially and seasonally, affects the efficiency of oxidation processes. Therefore, in this study, seawater samples were acquired from various locations in the Republic of Korea to understand the spatio-temporal patterns of marine dissolved organic matter. It was reported that the characterization of marine dissolved organic matter using liquid chromatography—organic carbon detector and excitation-emission matrix—parallel factor modeling. Furthermore, the effects of marine dissolved organic matter were evaluated on ozonation, an oxidation process. The results demonstrate that marine dissolved organic matter varies in its aquagenic, pedogenic, and intermediate characteristics based on region and season. These variations affect ozonation by influencing the consumption of oxidants (e.g., bromine). As a result, it was concluded that characterizing marine dissolved organic matter can help improve the effectiveness of oxidation processes, particularly ozonation. [Display omitted] • Marine DOMs in the Republic of Korea were separated into three components by PARAFAC. • DOM grouping with aromaticity and molecularity in humic substance diagram. • Evaluation of DOM source through systematic comparison using OpenFluor. • Components affecting the consumption of oxidant in seawater ozonation. [ABSTRACT FROM AUTHOR]

The remote injection casting process was developed using a high-capacity casting system in a mockup facility to secure the key technology for the fabrication of transmutation metallic fuels in hot cells. Seventy-eight fuel slugs fabricated simultaneously through remote injection casting were confirmed to satisfy the fabrication specification. The reaction characteristics of the coating candidates for the reusable crucible were investigated by using sessile drop tests with U-10wt%Zr-5wt%RE at 1450 °C for 1 h and LaYO 3 showed the smallest interaction width. The improvement in the adhesion of Y 2 O 3 coatings on the inner walls of the quartz mold was effective in reducing the reaction between the melt and the mold. The mechanical and chemical cleaning processes were investigated to remove the surface contamination layer of the melt residue for recycling. Both cleaning methods were effective with the mechanical treatment favored owing to the operations in hot cells. The remote injection casting process equipped with fuel loss control components developed in this work will fabricate transmutation fuels in hot cells. • A remote injection casting process was developed for transmutation metallic fuels. • Coating candidates for reusable crucibles were investigated by sessile drop tests. • Improvement in the coating adhesion reduced the interaction between melt and molds. • The surface layer of the melt residue was effectively cleaned for recycling. [ABSTRACT FROM AUTHOR]

Discriminating attention-related symptoms is a key factor for the appropriate diagnosis of attention deficit hyperactivity disorder (ADHD) and sluggish cognitive tempo (SCT). The Barkley Adult Attention Deficit Hyperactivity Disorder Rating Scale-IV (BAARS-IV) is the most widely used tool to measure such symptoms. This study investigated the psychometric properties of the BAARS-IV with a sample of 771 participants in the Korean population. We identified a five-factor model for measuring ADHD and SCT, and determined the scale was appropriate for use in the Korean population. Sustained attention (SA) was a unique factor of the Korean version of the BAARS-IV. Internal consistency was good and the positive association between the BAARS-IV and an alternative measure of depression/anxiety supported the scale's concurrent validity. To conclude, a cautious approach is needed when applying the BAARS-IV in different cultural contexts. [ABSTRACT FROM AUTHOR]

A peculiar NMR line shape was reported (J. Low Temp. Phys. 114 (1999) 173; Phys. Rev. B 57 (1998) 12595; Phys. Rev. B 55 (1997) R664) for a study of orientational ordering in submonolayer films of H2 molecules adsorbed on hexagonal boron nitride. This low-temperature (below 200 mK) NMR line shape was seen for relatively high ortho-H2 (o-H2) concentration (0.48 and was interpreted as a signature of the hindered rotor state. Preliminary results of recent computer simulations for the NMR line shapes of H2 molecules, however, indicate that the peculiar NMR line shape may be the result of a combination of three different NMR line structures, and suggest possible well-defined clusters in two dimensions with three different order parameters dominating the orientational ordering. In addition to the hindered rotor line shape, the order-parameter dependence of the quadrupolar glass NMR line shape will be discussed. [Copyright &y& Elsevier]

This study investigated the perception bias on affective emoticons in individuals with emotion dysregulation and a maladaptive regulation strategy. A total of 289 students from the university completed 1) the Cognitive Emotional Regulation Questionnaire, including both adaptive and maladaptive cognitive emotional strategies, 2) the Difficulties in Emotion Regulation Scale, 3) an emoticon rating in terms of perception intensity, based on 6 basic emotions. Twenty-six emoticons from KakaoTalk, a popular messenger application in South Korea, were used after arousal whereupon valence ratings were obtained. The results revealed that individuals with emotion dysregulation significantly displayed stronger perception to ambiguous affect emoticons in anger and fear emotions, as compared to the control. These findings suggest that individuals with emotion dysregulation may be more influenced by negative affect stimuli which then leads to daily negative affect bias. [ABSTRACT FROM AUTHOR]

A simple and convenient design enables real-time three-dimensional position tracking of nitrogen-vacancy (NV) centers in diamond. The system consists entirely of commercially available components (a single-photon counter, a high-speed digital-to-analog converter, a phase-sensitive detector-based feedback device, and a piezo stage), eliminating the need for custom programming or rigorous optimization processes. With a large input range of counters and trackers combined with high sensitivity of single-photon counting, high-speed position tracking (upper bound recovery time of 0.9 s upon 250 nm of step-like positional shift) not only of bright ensembles, but also of low-photon-collection-efficiency single to few NV centers (down to 103 s−1) is possible. The tracking requires position modulation of only 10 nm, which allows simultaneous position tracking and pulsed measurements in the long term. Therefore, this tracking system enables measuring a single-spin magnetic resonance and Rabi oscillations at a very high resolution even without photon collection optimization. The system is widely applicable to various fields related to NV center quantum manipulation research such as NV optical trapping, NV tracking in fluid dynamics, and biological sensing using NV centers inside a biological cell. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated how an individual's time perspective of the present and the future affects the delay of gratification, using the construal level theory. In addition, the mechanisms that influence the time perspective on the delay of gratification were examined through the mediating roles of the psychological distance and the perceived possibility of getting a future reward. Participants and Methods: One hundred twenty university students completed the Korean version of the Swedish Zimbardo Time Perspective Inventory (S-ZTPI) and performed a Temporal Discounting task to aid in the evaluation of their ability to delay gratification. Their psychological distance to the future and perceived possibility of getting a future reward were measured using the visual analogue scale. Results: The results showed that once the Present-Hedonistic and Future-Negative from among the six-time perspectives increased, and the ability to delayed gratification decreased. On the other hand, once the Future-Positive time perspective increased, the ability to delayed gratification increased. Only the psychological distance for 9 months was associated with time perspective and the mediation effect was not significant. Present-Hedonistic time perspective negatively predicted the perceived possibility of getting a future reward and the delay of gratification. The perceived possibility of getting a future reward fully mediated the relation between the Future-Negative time perspective and the delay of gratification. Conclusion: These findings suggest that problems involved with the delay of gratification (such as smoking, addiction, and binge eating behavior) are more likely to occur in people who have high Present-Hedonistic and Future-Negative time perspectives, because these time perspectives lead to a lower perceived possibility of getting a future. [ABSTRACT FROM AUTHOR]

We investigated the differences in the emotional experiences of people who smoke and have damaged interoceptive awareness. Interoception is the sensation of the physiological condition of the body, and it has 2 biases: neglect and amplification of bodily feedback. We recruited 72 participants and divided them into 4 groups according to smoking status and interoceptive bias based on their scores on the Multidimensional Assessment of Interoceptive Awareness. All groups assessed their physiological and subjective arousal before and after watching video clips (positive–low arousal, positive–high arousal, negative–low arousal, negative–high arousal, neutral). The results indicated that people with amplification (vs. neglect) bias who smoked showed stronger subjective arousal to neutral stimuli. In contrast, people with amplification (vs. neglect) bias who did not smoke showed stronger subjective arousal to positive stimuli. These findings suggest that people who smoke and have an amplification bias could be more likely to misinterpret neutral emotional stimuli, leading to an increased craving for smoking. [ABSTRACT FROM AUTHOR]