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This work develops a polarisation-tunable reflector that is based on a guided-mode resonant (GMR) filter with an integrated liquid-crystal (LC) polarisation rotator. The GMR filter serves as a linear polariser that strongly reflects linearly polarised light with high polarisation extinction ratio of 20:1 and sharp reflection band of ~20 nm in width. The LC polarisation rotator comprising an LC cell and quarter-wave plate can electrically control the polarisation orientation of the reflected light from the GMR. The required applied voltage for arbitrary polarisation rotation between 0° and 180° is less than 4.1 V. This dynamically tunable polarised reflector is also compact, integrable into optical circuits, and easily fabricated, showing high potential for practical and widespread applications. [ABSTRACT FROM AUTHOR]

The high overpotential caused by the slow kinetics of oxygen reduction (ORR) and oxygen evolution (OER) has greatly limited the practical application of lithium‐oxygen (Li−O2) batteries. The adoption of force‐field‐assisted system based on a newly developed piezocatalysis is promising in reducing the overpotential. Herein, a force‐assisted Li−O2 battery is first established by employing MoS2/Pd nanocomposite cathode, in which the piezoelectric polarization as well as built‐in electric field are formed in MoS2 piezoelectric catalyst under ultrasound activation, leading to the continuously separated electrons and holes to enhance the ORR and OER kinetics. Moreover, the introduction of Pd can promote the electrons transfer and further inhibit the complexation of electron–hole pairs, contributing to enhanced catalytic activity in the decomposition/generation of discharge products, resulting in reduced discharge/charge overpotentials. Thus, the force‐assisted MoS2/Pd‐based Li−O2 battery is capable of adjusting the output and input energies by the assisted ultrasonic wave. An ultra‐low charging platform of 2.86 V and a high discharging platform of 2.77 V are achieved. The proposed unique force‐assisted strategy can also be applied to lithium carbon dioxide battery system through the effective reduction and separation of CO2 and CO32−, providing significant insights in achieving efficient energy conversion for metal−air batteries. [ABSTRACT FROM AUTHOR]

Force-assisted lithium-carbon dioxide battery relies on piezoelectric catalysis principle to generated electrons and holes promote carbon dioxide reduction and evolution to improve battery performance, providing a new strategy for developing lithium-carbon dioxide battery in energy storage. [Display omitted] The use of light-assisted cathode is regarded as an effective approach to reduce the overpotential of lithium carbon dioxide (Li − CO 2) batteries. However, the inefficient electron-hole separation and the complex discharge–charge reactions hamper the efficiency of CO 2 photocatalytic reaction in battery. Herein, a highly reversible force-assisted Li − CO 2 battery has been established for the first time by employing a Bi 0.5 Na 0.5 TiO 3 nanorods piezoelectric cathode. The high-energy electron and holes generated by the piezoelectric cathode with ultrasonic force can effectively enhance the carbon dioxide reduction reaction (CDRR) and carbon dioxide evolution reaction (CDER) kinetics, thereby reducing the overpotentials during the discharge–charge processes. Moreover, the morphology of the discharge product (Li 2 CO 3) can be modified via the dense surface electrons of the piezoelectric cathode, resulting in the promoted decomposition kinetics of Li 2 CO 3 in charging progress. Thus, the force-assisted Li − CO 2 battery with the unique piezoelectric cathode can adjust the output and input energy by ultrasonic wave, and provides an ultra-low charging platform of 3.52 V, and exhibits excellent cycle stability (a charging platform of 3.42 V after 100 h cycles). The investigation of the force-assisted process described herein provides significant insights to solve overpotential in the Li − CO 2 batteries system. [ABSTRACT FROM AUTHOR]

Low-temperature sintering of 0.5Pb(Zn1/3Nb2/3)O3–0.5Pb(Zr0.47Ti0.53)O3 ceramics (0.5PZN–0.5PZT) was investigated using Li2CO3 as sintering aids. The addition of Li2CO3 significantly improved the sinterability of 0.5PZN–0.5PZT ceramics, resulting in a reduction of sintering temperature from 1100 to 950 °C. Moreover, the effect of Li2CO3 addition on the dielectric and piezoelectric responses in 0.5PZN–0.5PZT systems was systematically studied in this work. The analysis of x-ray diffraction patterns and scanning electron microscopy indicated that the solubility limit of Li ions in perovskite structures was near 0.5 wt % in Li2CO3 form. Below the solubility limit, Li+ ions entered the six-fold coordinated B sites of oxygenic octahedral center and enhanced the compositional fluctuation in nanoscale, resulting in the increase of the degree of diffuseness γ. While at high doping level above the solubility limit, γ decreased subsequently, which was attributed to the formation of pyrochlore phase. Raman analysis on the B-site cation order correlates well with the dielectric measurement results. The large improvements in the piezoelectric properties such as the coupling factor and piezoelectric constant were also observed for doped specimens. Optimized parameters, such as d33=278 pC/N, kp=0.50, and [variant_greek_epsilon]max=8800, were achieved by doping 0.5 wt % Li2CO3 in low-temperature sintered 0.5PZN–0.5PZT systems, which shows great promise as practical materials for multilayered piezoelectric device applications. The observed improvement in the electric properties can be attributed to the grain size effect. After doping, the clamping effect caused by oxygen vacancies and grain boundary phases on domain wall motion was largely reduced due to the increase of grain size; therefore, a significant reduced coercive field and an increased remanent polarization were observed in doped 0.5PZN–0.5PZT systems. [ABSTRACT FROM AUTHOR]

Relaxor ferroelectrics of 0.5Pb(Zn1/3Nb2/3)O3–0.5Pb(Zr0.47Ti0.53)O3 (0.5PZN–0.5PZT) near the morphotropic phase boundary (MPB) were prepared using the conventional oxide mixing method. The influence of sintering temperature on the phase transition and dielectrical response in the relaxor-ferroelectric-system 0.5PZN–0.5PZT has been investigated. X-ray diffraction analysis indicated that the phase of the material changed from an initially rhombohedral structure to a MPB structure and then a tetragonal structure when the sintering temperature is increased from 900 to 1250 °C. The corresponding grain size is enlarged from 1.1 μm for predominantly rhombohedral to 2.5 μm for more than 60% tetragonal, which obeys the common grain-growth law. The dielectric studies revealed that the indicator of the degree of diffuseness γ decreased with the increase of the sintering temperature from 900 to 1150 °C, indicating that the dielectric relaxor behavior was weakened, while at high sintering temperature above 1250 °C, γ increased subsequently, which was attributed to the Pb vacancy due to the formation of a pyrochlore phase. Raman analysis on the B-site cation order correlates well with the dielectric measurement results. [ABSTRACT FROM AUTHOR]

• A bistable electrical switching between two planar states can be realized by pitch jumps. • A polymer network was fabricated to provide a balance between two planar states in the neighborhood of a pitch jump. • The field-induced distortion in the polymer network generates the mechanical force causing the pitch jump transition. • Both planar states with different pitches can shift the wavelength of Bragg reflection. Chiral nematic liquid crystals (CLCs) are highly promising tunable photonic materials that own various states and exhibit different optical properties in each state. The natural bistability between planar and focal conic states is widely exploited in power-saving applications. This work proposes another bistable electrical switching mode that involves two planar states that are realized by pitch jumps in polymer-stabilized chiral nematic liquid crystals (PSCLCs) with negative anisotropy. Under an appropriate polymerization condition, a polymer network can be formed throughout the CLC cell; it not only eliminates the original pitch jump behavior that is associated with thermal hysteresis in CLCs but also provides a balance between two planar states in the neighborhood of a pitch jump. The helical pitch of the PSCLC can be reversibly switched from the long pitch to the short pitch by applying pulse direct current (DC) voltages. The switching mechanism involves field-induced distortion in the polymer network, which generates the mechanical force that causes the pitch jump transition. Both planar states with different pitches can shift the wavelength of Bragg reflection, which depends strongly on the thickness of the PSCLC cells. A tunable laser that is based on a dye-doped PSCLC cell is fabricated and its wavelength-tuning ability is demonstrated. [ABSTRACT FROM AUTHOR]

This study aims to make a deep exploration into e-readiness from the viewpoints of technology, management, organization, and environment in order to understand how these dimensions affect the acceptance intention and degree of implementation of a corporate website. A mail survey was conducted. A total of 753 questionnaires were distributed and collected from SMEs’ senior executives, generating 163 usable replies with a total response rate of 21.65%. The structural equation modeling (SEM) technique and partial least squares (PLS) software were used to conduct a path analysis for related variables in the research model. Results of the data analysis show that (1) the variables that have a significant positive effect on the intention to accept a corporate website in SMEs are an awareness of corporate website, enterprise resources, technological resources, government e-readiness, market force e-readiness, and supporting industries e-readiness and (2) the variables that have a significant effect on the degree of corporate website implementation in SMEs are an awareness of corporate website, senior executive commitment, corporate website governance, human resources, technological resources, government e-readiness, and market force e-readiness. Through the empirical results, this study provides contributions for SME managers and researchers. [ABSTRACT FROM AUTHOR]

Zinc-ion batteries are considered as one of the most promising electrochemical energy storage devices in the field of electrochemical energy storage due to their low cost and high safety. However, the development of zinc ion batteries using metal zinc anodes is limited by the existence of hydrogen evolution, dendrite growth, serious side reactions, low coulomb efficiency and poor cycling performance. In this work, an ultrathin ZnF 2 /Zn 3 Sb 2 hybrid interfacial layer is constructed by spraying commercial Zn metal with SbF 3 as the precursor. Due to the high Zn ionic conductivity of ZnF 2 and Zn 3 Sb 2 , this interfacial layer can effectively enhance the uniform deposition of Zn ions and improve the stability of the solid electrolyte/anode interface. A low current density of 1 mA cm−2 and a high current density of 1 mA cm−2 can be obtained by assembling symmetric batteries with Zn@SbF 3 as the anode for more than 500 h. In addition, the CuSCoS//Zn@SbF 3 full battery maintains a CE rate of up to 99.2% after 1000 cycles at a current density of 2 A g−1. These results indicate that the modified Zn anode holds a large potential for Zinc-ion batteries applications. • We used SbF 3 as a precursor to form an ultra-thin ZnF 2 /Zn 3 Sb 2 hybrid interface layer for the first time. • The interface layer can effectively improve the uniform deposition of Zn. • We synthesized CuSCoS cathodes for the first time and assembled zinc-ion full cells with SbF 3 @Zn. [ABSTRACT FROM AUTHOR]

Abstract: The current research presents a theoretically sound model of the effects of the characteristics of information systems (IS) on the perception of end-users regarding computer self-efficacy and outcome expectations. The relationships among factors of small- and medium-sized enterprises in Taiwan are examined based on the IS success model and social cognitive theory. A mail survey was conducted, generating 284 usable responses with a total response rate of 51.64%. Structural equation modeling was employed to assess the relationships among related constructs. Data analysis shows that (1) no direct links exist between computer self-efficacy and either information quality or service quality, although certain effects are observable on system quality; (2) the relationships between outcome expectations and both system quality and service quality are significant; however, the relationship with information quality is insignificant; and (3) outcome expectations mediate the effects of computer self-efficacy on end-user satisfaction. The implications of the results are provided, and directions for future research are discussed in the study. [Copyright &y& Elsevier]

Abstract: The activated carbon (AC) electrode was prepared and carbonized at 850°C for electrosorption desalination. As a result, the electrical double-layer capacitance of AC electrode was improved by 2.16 times by carbonization. In order to improve the desalination performance of AC electrode, it was modified by loading titania with sol-gel method. The electrodes were analyzed using scanning electron microscope (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD) and electrochemical workstation. The results revealed that there was a certain amount of titania on the surface of modified AC electrode, which was accumulated on the surface of electrode forming some flocculent substance and its crystalline phase was rutile. After modification, the forming rate of electrical double-layer and electrosorption capacity of AC electrode were obviously improved and its desalination ratio was increased by 62.7%, whereas physical adsorption was decreased. In addition, compared with AC electrode, activated carbon fiber (ACF) electrode, and carbon nanotube (CNT) electrode, the AC loaded titania (AC-TiO2) electrode exhibited relatively higher desalination and desorption ratios as well as a reasonable cost. Therefore, the AC-TiO2 electrode would be suitable for the application of electrosorption desalination in the practical industry. [Copyright &y& Elsevier]

Abstract: The secondary flow is frequently used to enhance the convective heat transfer. In this paper, the cross-averaged absolute vorticity flux in the main flow direction is used to specify the intensity of the secondary flow produced by vortex generators that are mounted on a three-row flat tube bank fin surfaces. The relationship between the intensity of the secondary flow and the strength of convective heat transfer is studied using a numerical method. The results reveal that cross-averaged absolute vorticity flux in the main flow direction can reflect the intensity of the secondary flow; a significant relationship between this cross-averaged absolute vorticity flux and span-averaged Nusselt number exists for the case studied. This cross-averaged absolute vorticity flux can account only for the secondary flow effects on convective heat transfer but cannot quantify the effects of developing boundary layer on convective heat transfer. [Copyright &y& Elsevier]

Dimming and scattering control are two of the major features of smart windows, which provide adjustable sunlight intensity and protect the privacy of people in a building. A hybrid photo- and electrical-controllable smart window that exploits salt and photochromic dichroic dye-doped cholesteric liquid crystal was developed. The photochromic dichroic dye causes a change in transmittance from high to low upon exposure to sunlight. When the light source is removed, the smart window returns from colored to colorless. The salt-doped cholesteric liquid crystal can be bi-stably switched from transparent into the scattering state by a low-frequency voltage pulse and switched back to its transparent state by a high-frequency voltage pulse. In its operating mode, an LC smart window can be passively dimmed by sunlight and the haze can be actively controlled by applying an electrical field to it; it therefore exhibits four optical states—transparent, scattering, dark clear, and dark opaque. Each state is stable in the absence of an applied voltage. This smart window can automatically dim when the sunlight gets stronger, and according to user needs, actively adjust the haze to achieve privacy protection. [ABSTRACT FROM AUTHOR]

Peptidoglycan recognition proteins (PGRPs) play an important role in innate immunity by recognizing components of pathogenic bacteria (such as peptidoglycan, PGN) and are evolutionarily conserved pattern recognition receptors (PRRs) in both invertebrates and vertebrates. In the present study, two long-type PGRPs (designed as Eco-PGRP-L1 and Eco-PGRP-L2) were identified in orange-spotted grouper (Epinephelus coioides), which is a major economic species cultured in Asia. The predicted protein sequences of both Eco-PGRP-L1 and Eco-PGRP-L2 contain a typical PGRP domain. Eco-PGRP-L1 and Eco-PGRP-L2 exhibited organ/tissue-specific expression patterns. An abundant expression of Eco-PGRP-L1 was observed in pyloric caecum, stomach and gill, whereas a highest expression level of Eco-PGRP-L2 was found in head kidney, spleen, skin and heart. In addition, Eco-PGRP-L1 is distributed in the cytoplasm and nucleus, while Eco-PGRP-L2 is mainly localized in cytoplasm. Both Eco-PGRP-L1 and Eco-PGRP-L2 were induced following the stimulation of PGN and have PGN binding activity. In addition, functional analysis revealed that Eco-PGRP-L1 and Eco-PGRP-L2 possess antibacterial activity against Edwardsiella tarda. These results may contribute to understand the innate immune system of orange-spotted grouper. • Two long-type PGRP, named as Eco-PGRP-L1 and Eco-PGRP-L2, were identified from orange-spotted grouper. • Eco-PGRP-L1 and Eco-PGRP-L2 are inducible following PGN stimulation and can bind with PGN. • Eco-PGRP-L1 and Eco-PGRP-L2 activate NF-κB signaling and exhibit antibacterial activity. [ABSTRACT FROM AUTHOR]

Abstract: Two new compounds [Cu(enMe)2][Cu(enMe)2(H2O)][SiMoV 6MoVI 6Sb2O40] (1) and [Ni(en)2]2[SiMoV 6MoVI 6Sb2O40] (2) (enMe=1,2-diaminopropane, en=1,2-ethylenediamine) have been hydrothermally synthesized and characterized by IR, UV–Vis spectroscopy, X-ray photoelectron spectroscopy (XPS), powder XRD analyses, elemental analyses and single crystal X-ray diffraction. The two compounds represent the first examples of hybrids based on bi-antimony capped Keggin polyanions {SiMo12Sb2O40} and different transition metal coordination complexes. [Copyright &y& Elsevier]

A superhydrophobic surface that has controllable adhesion and is characterized by the lotus and petal effects is a powerful tool for the manipulation of liquid droplets. Such a surface has considerable potential in many domains, such as biomedicine, enhanced Raman scattering, and smart surfaces. There have been many attempts to fabricate superhydrophobic films; however, most of the fabricated films had uniform adhesion over their area. A patterned superhydrophobic surface with spatially controllable adhesion allows for increased functions in the context of droplet manipulation. In this study, we proposed a method based on liquid-crystal/polymer phase separation and local photopolymerization to realize a superhydrophobic surface with spatially varying adhesion. Materials and topographic structures were analyzed to understand their adhesion mechanisms. Two patterned surfaces with varying adhesion were fabricated from a superhydrophobic material to function as droplet guides and droplet collectors. Due to their easy fabrication and high functionality, superhydrophobic surfaces have high potential for being used in the fabrication of smart liquid-droplet-controlling surfaces for practical applications. [ABSTRACT FROM AUTHOR]

Abstract: Secondary flow is the flow on the cross section normal to the main flow. It can greatly enhance the convective heat transfer. Mounting or punching vortex generators (VGs) on heat transfer surface can produce secondary flow. The heat transfer of circle tube bank fin heat exchanger with VGs or without VGs on the fin surface having ten different configurations (different fin spacing, height and attack angle of VGs) was numerically studied. It is found that if a non-dimensional parameter based on the absolute vorticity flux is introduced to specify the intensity of secondary flow, the volume average non-dimensional intensity of secondary flow has one-to-one correlation with Nusselt number for all the cases studied, but there is no such correlation with the friction factor. Considering the pressure drop produced by the shape of VGs, the ratio of cross section area reduction after introducing VGs is introduced to modify the friction factor. At the same fin spacing, both Reynolds number and the volume average non-dimensional intensity of secondary flow have one-to-one correlation with the modified friction factor. These results reveal that secondary flow intensity determines the heat transfer characteristics of the fin surfaces of circle tube bank fin heat exchanger only. [Copyright &y& Elsevier]