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Regenerable methods for phosphate (P) recycling have received intense attention due to their potential environmental and economic benefits. In this study, to improve the electrosorptive removal of P in membrane capacitive deionization, an activated carbon (AC) electrode was coated with a heterogeneous anion-exchange resin layer, and named the AE-AC composite electrode. It was shown that the AE-AC electrode exhibited a good capacitive behavior for electrical double-layer charging. The batch-mode experiments indicted that when the solution pH changed from 5 to 8, the predominant P species shifted from monovalent H2PO4− to divalent HPO42− that was preferentially electroadsorbed for competitive electrosorption with Cl−. Importantly, the AE-AC composite electrode significantly increased the selectivity coefficient of P over Cl− to 0.56 that was 2.24-fold greater than that of the uncoated AC electrode, at 1.2 V in single-pass mode operation. This improvement can be ascribed to the preferential transport of P through the thin coating layer containing quaternary amine functional groups. The permselectivity of the coating also significantly increased the electrosorption capacity of P from 0.031 to 0.101 mmol/g with a high charge efficiency (97%) by the reduction in the co-ion repulsion effect. When the reverse voltage (−1.2 V) was applied, electroadsorbed P was reversibly desorbed from the AE-AC electrode in repeated operation. This work suggests that coating an anion-exchange resin layer on the surface of a carbon electrode shows great potential to improve the selective removal of P through electrosorption.

Carbon monoxide (CO) plays an important role in signaling in cells, making its use as a therapeutic tool highly intriguing. Reduced burst emissions are important to avoid the cytotoxicity and tissue damage caused by CO. Here, we developed a stable diiron carbonyl [FeFe] hydrogenase agent that enables prolonged CO release activity (half-life of over 9 h) in cells. The integrated analysis allowed the identification of the key intermediate sites and CO accumulations with subcellular resolution. We observed that the [FeFe]

The interactive influences between carbon crystallinity and electrochemical activation (EA) on the capacitive behavior for a series of soft carbons (SCs) modified with KOH have been systematically examined for the high-voltage (≥ 4.0 V) super-capacitors in the conventional liquid electrolyte of 1 M tetraethylammonium tetra-fluoroborate/propylene carbonate (TEABF4/PC). The energy storage behavior of SCs without and with the KOH modification as well as before and after the EA treatment in various potential regions are investigated by galvanostatic charge/discharge (GCD) and cyclic voltammetry (CV) tests. Characterizations including scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy, nitrogen adsorption/desorption isotherms are employed to probe possible changes in carbon structure after the KOH and EA treatments. The results show that the specific capacitance of SCs can be significantly promoted by the KOH modification through crystallinity reducing and the EA via the irreversible insertion of either BF4 − or TEA+. The EA process is found to be more effective for KOH-modified SCs with relatively low crystallinity. After the optimization of both positive and negative electrodes, a 4 V full cell with the specific energy of 71.2 and 54.9 Wh kg−1 at the specific power of 0.9 and 6.1 kW kg−1 can be obtained. This 4 V supercapacitor also delivers the superior energy density of 37.7 Wh l−1 at 0.5 kW l−1 and 29.1 Wh l−1 at 3.2 kW l−1. For the stability, the 4 V supercapacitor exhibits about 85% capacitance retention after 10000 GCD cycles. The results have demonstrated the application potential of KOH-modified SCs as promising electrode materials for the high-voltage supercapacitors.

A simple and environmentally friendly route is developed to produce flower-like MnO2/graphene hydrogel (MnO2/GH) composites with mesoporous structure. The results show that flower-like MnO2 is firm...

An efficient approach for in-band radar cross section (RCS) reduction of microstrip patch array antenna without employing extra-low RCS artificial materials is proposed and analysed. The element of...

2D extended organic cocrystals were constructed using 1,4-diiodotetrafluorobenzene and aromatic aldehydes via IOaldehyde halogen bonds on an Au(111) surface. The competition and synergy of halogen bonds and hydrogen bonds in 2D co-crystallization were revealed by scanning tunneling microscopy.

We evaluate the quantum transport through one mesoscopic circuit with its embedded quantum dot coupled to the Majorana bound states (MBSs) at the ends of one topological-superconductor nanowire . The calculation results show that when the MBSs co-couple to the dot, antiresonance effect has an opportunity to take place, and the antiresonance point is related to the inter-MBS coupling. Moreover, once the dot-MBS coupling strengths are equal to each other, the Fano effect takes place, manifested as the Fano lineshape in the transmission-function spectrum. The results in this work can provide new information for the understanding of the MBS-contributed quantum transport through quantum-dot systems.

High-efficiency recycling technology for endangered elements effectively mitigates the risk of resource shortages and promises the sustainability of supply chains, which is significant to the industry. In this study, an activated carbon (AC)-based capacitive deionization (CDI) for the selective electrosorption and recovery of indium ions (In3+) from acidic aqueous solution is proposed. The effects of applied voltage, pH, and initial concentration of indium were investigated to optimize the operation parameters for In3+ electrosorption. The results of cyclic voltammetry and the galvanostatic charge/discharge measurements indicate that the AC electrode shows good capability for the electrosorption of In3+ based on electrical double-layer capacitance. As demonstrated, In3+ can be successfully removed by CDI without deposition when the pH

We construct one mesoscopic circuit in which one quantum dot couples to one DIII-class topological superconductor and one s-wave superconductor, in addition to its connection with the metallic lead. And then, the Andreev reflection current in the metallic lead is evaluated. It is found that the two kinds of superconductors drive the Andreev reflection in the constructive manner. Next as finite superconducting phase difference is taken into account, the Andreev reflection oscillates in period π 2 , and it can be suppressed in the low-energy region if the superconducting phase difference is ( n + 1 2 ) π 2 (n ∈ Integer). Such a result is almost independent of the increase of the intradot Coulomb interaction. Therefore, this structure can assist to realize the manipulation of the Andreev reflection. Also, the result in this work provides useful information for understanding the property of the DIII-class topological superconductor.

The Kondo effect in the T-shaped double-quantum-dot structure is theoretically investigated, by considering different adjustments of the quantum dot levels. It is shown that when the quantum dot levels are shifted to the electron–hole symmetry point, the two-stage Kondo effect can be induced at the limit of weak interdot coupling. However, with the increase of interdot coupling, the interdot antiferromagnetic correlation modifies the Kondo effect efficiently, leading to the destruction of the conductance plateau. If the dot levels are detuned, the low-temperature entropy transition will exhibit new results and complicated transport behaviors occur. The reason also arises from the competition between the Kondo effect and the interdot antiferromagnetic correlation. We believe that these results are helpful for the further understanding of the Kondo physics in the T-shaped double-dot structure.

The formation of chiral nanostructures via molecular assembly and reaction on solid surfaces is a ubiquitous surface process due to the symmetry-breaking at 2D surface. Studying chirality during the adsorption, assembly, and reaction of molecules on 2D solid surfaces at molecular level not only sheds deep insights into the enantioselective heterogeneous catalysis, chiral recognition, origin and evolution of chirality, and many important physical chemistry processes but also provides an important strategy to create chiral nanostructures. Here, we give a survey of recent advances in chiral expression and control in molecular assemblies and reactions on surfaces. We firstly give a brief introduction to the general concepts of chiral molecular nanostructures on surfaces. And then we focus on the induction and control of chirality expressed in molecular assemblies. The recent developments in the control strategies such as chiral co-adsorber, chiral auxiliary, chiral solvent, chiral templated surfaces, as well as the underlying mechanism to achieve the chiral induction and amplification, are reviewed. After that, we review the studies of chirality expressed in on-surface synthesis which has been proved to be a promising strategy to fabricate covalently bonded low-dimensional nanostructures and materials. In this respect, we introduce the chiral expression in the intramolecular and intermolecular coupling reactions on surfaces. In addition, we survey the methods to steer the stereoselectivity of on-surface reactions including the design of precursor structure, steric hindrance effect, substrate, kinetic parameters et al. Finally, the future outlook in this field is discussed.

A series of twisted D–π–A type emitters based on the acridine donor unit and CN-substituted pyridine, pyrimidine, and benzene acceptor units are studied. They not only allow one to systematically probe the influence of different acceptor strengths, but also permit one to intriguingly probe the influence of tunable conformations (twist angles) within the acceptor moieties through controlling the orientation of asymmetric heteroaromatic ring relative to the donor component. Intramolecular charge-transfer transitions are observed in all these compounds and emission wavelengths are widely tunable from deep blue to yellow not only by the general acceptor strength due to the characters of heteroarene and CN-substitution pattern but also by the subtle control of in-acceptor conformation (twist angles). Small triplet-to-singlet energy gaps (ΔEST) and significant thermally activated delayed fluorescence (TADF) characteristics are obtained in a series of D–π–A compounds with sufficient acceptor strengths and tunable in-acceptor conformation, yielding a series of efficient blue-green to yellow TADF emitters with promisingly high photoluminescence quantum yields of 90%–100%. Highly efficient blue-green to yellow TADF organic light-emitting diodes (OLEDs) having external quantum efficiencies of up to 23.1%–31.3% are achieved using these efficient TADF emitters, which are among the most efficient TADF OLEDs ever reported.

Light-emitting diodes (LEDs) are efficient light sources extensively applied in people’s daily life nowadays, with profound effect on their psychological and physiological state subtly and deeply. The correlated color temperature (CCT) the eyes perceive is a key parameter, but the CCT tuning technology of LEDs remains in the development stage. In this study, an electrochromic (EC) material is employed in the tuning device, exhibiting a wide CCT tuning range from 3200 K to 6900 K, varying almost along the black-body locus. The driving voltage is lower than 2.4 V, with luminosity loss less than 16 %. Using the EC materials, the performance of CCT tuning technology is able to be further enhanced.

The pathophysiological changes in cells are mainly focusing on the ionic regulations like hyperpolarization, depolarization etc. The real-time monitoring of these changes in ionic behavior is one of the challenging areas in the biosensor field. A field-effect transistor (FET) based sensor system shows an exceptional advantage in noninvasive real-time monitoring of cellular changes. In this study, we monitored cell proliferation in real-time by using the FET biosensor. Cells were cultured on the FET sensing surface and the potential difference was monitored using the Electric-double-layer field-effect transistor (EDL-FET) biosensor system. Cell proliferation in the sensor surface was electrically measured as drain current change. The impedance measurement changes revealed the capacitive equivalent model of the FETs system. The most important factor in a cell-based system is to overcome the limited life span of cells in sensor platforms. This sensor platform was capable of monitoring cell growth and proliferation, compared with other conventional and current cell sensor platforms. Rapid electrical response corresponding to the cell growth and other functional changes associated with the cell can be used in many fields, including medicine, environmental monitoring and drug screening.

By considering quantum impurities in the superconductors, we mimic their influences on the phase transition in a Josephson junction. It is found that the impurities in the superconductors can take nontrivial effects to the Josephson phase transition, and they are able to promote or hinder the 0 → π phase-transition phenomenon. Namely, for the 0 ( π ) junction with one impurity, it has an opportunity to become a π (0) junction, following the adjustment of the impurity-superconductor coupling. However, when each superconductor has an embedded impurity, their effect on the phase transition tends to become weak. We believe that this work can be helpful in understanding the contribution of impurities to the Josephson phase transition.

We investigate the Josephson effect in a superconductor/triple-quantum-dot/superconductor junction in which the central dot is coupled to the superconductors. It is found that the supercurrent exhibits rich 0–π phase translations due to the interplay between interdot spin and electron correlations. Moreover, when the side dots are half-occupied, the nonlocal spin correlation between them, i.e., ferromagnetic or antiferromagnetic, coincides well with the supercurrent phase. We thus consider such a system to be a promising candidate for controlling the nonlocal magnetic configuration based on the Josephson effect.

We report that the supramolecular liquid-crystal (LC) physical gel can be formed through the fibrous self-assembly of the polyfluorene-based π-conjugated polymer, poly(9,9-dioctylfluorene-alt-benzothiadiazole) (F8BT), in twisted nematic LC system for the first time. With the utility of alignment layers, the F8BT molecules can be aligned and formed the LC physical gels with the formation of self-assembled supramolecular structures in the twisted nematic LCs. In contrast to conventional LC physical gels, the presence of anisotropic π-conjugated structure makes the twisted nematic LC system exhibit excellent electro-optical properties of driving voltage reduction and contrast ratio enhancement owing to the conjugated polymer having a high π-electron delocalization degree which can efficiently drive LC molecules in much lower operating voltages. The self-assembled supramolecular network has revealed the potential for applying in various LC display devices with the ability of improving their electro-optical performance.

The effect of main gas flow rate and gas type of carrier gas on the electrical and optical properties of Ga-doped ZnO films deposited by atmospheric pressure plasma jet was investigated. Adding Ar and H 2 in the carrier gas reduces the sheet resistance of the films from 230 to 90 Ω/□ and increases the deposition rate by 38% due to the incorporation of hydrogen as a shallow donor and the lower breakdown potential of Ar, respectively. The effect of the main gas flow rate is less significant compared with the gas type of the carrier gas, but a proper flow rate is required to produce the film with lower resistivity. The lowest resistivity of 1.25 × 10 − 3 Ω cm was achieved with a carrier gas mixture percentage of 75% and a main gas flow rate of 30 slm at a substrate temperature of 180 °C in open air. All the samples presented in this study exhibit average transmittance above 80% in the visible region and low haze below 5.5%.

In stereoscopic displays, crosstalk is typically observed when the views for both eyes are not clearly separated. Crosstalk affects the quality of 3D images and can cause visual fatigue in observers. According to the results of perception experimentation, different visual depth (disparity) and motion blur can also affect the perception of 3D image quality. Therefore, considering the effects of crosstalk, disparity, and motion blur, we propose an evaluation index to quantify 3D image performance for stereoscopic displays. This index assesses the optical quality of a 3D display as well as the effects of image content. According to human vision experimentation, the 3D image index $(\Delta {\rm X}_{\rm 3D})$ is validated to have a high positive correlation (0.8) with human perception. After combining the human visual mechanism and $\Delta {\rm X}_{{{\rm 3D}}}$ , the proposed index can represent the visual quality of static and dynamic images on stereoscopic displays.

A thermally activated delayed fluorescent (TADF) emitter (DMAC-TRZ) was reported either as the emitting dopant in a host or as the non-doped (neat) emitting layer to achieve high EL EQEs of up to 26.5% and 20% in OLEDs, respectively.

The tribological characteristics of Zirconia–Alumina composites with or without a three-layered structure in dry friction environment were studied by wear testing, XRD analysis and worn surfaces morphologies. The results indicate that both the friction coefficient and the wear rate of the former are lower than those of the composites without three-layered structure in the same tested conditions. Load as well as rotational velocity affects noticeably the tribological properties of the composites possibly due to the change of the wear mechanisms. For the layered composites, micro fracture dominates wear mechanism at the lower loads but adhesive wear derived from plastic deformation becomes dominating at the higher loads. For the non-layered composites, spalling fatigue resulted from grain breakage and pull-out appears as the dominating mechanism. The special layered structure and composition design brought a residual compressive stress in the layered composites and correspondingly restricted the tetragonal-monoclinic (t–m) phase transform of ZrO 2 after sintering. Therefore, there are lots of plastically deformed strips in the worn surface of the layered composites.

Monodispersed gold nanoparticles (AuNPs) were simultaneously decorated with lactosylated and non-modified shorter poly(ethylene glycol)s (PEGs) to enhance their target recognition. The decoration with sufficiently shorter PEGs dramatically enhanced the multivalent binding ability of lactosylated AuNPs to the lectin-fixed surface, possibly due to the enhanced mobility of the ligands via the spacer effect generated by the shorter PEG chains.

To increase line-of-sight (LOS) tracking and pointing accuracy of an Optic-Electro (O-E) landing guidance system, this work explores how to isolate the LOS tracking and pointing of a O-E theodolite from the carrier motion disturbance. A carrier-based O-E theodolite model was established with various disturbance factors introduced. Three kinds of controllers, Lead-lag, LQG/LTR(Linear Quadratic Gaussian/Loop Transfer Recovery) and H were designed to improve the stability and performance of the system. The Kalman filter and H weighting matrix were investigated in detail. Then, the controllers were emulated in Matlab and verified on a swing bench. The compared experiments for the three kinds of controllers on time domain, frequency response and stability were performed. Obtained results show that both LQG/LTR and H controllers can satisfy the design specifications, and their decoupling effects are as deep as 50 dB, which can ensure precise tracking and pointing performance of LOSs in O-E landing guidance systems.

We investigate the influences of the boundary conditions on the ground state properties of a dimerized S=1 Ising chain with single-ion anisotropy, which are solved exactly by means of a mapping to the spin-1/2 Ising chain with the alternating transverse fields and the Jordan–Wigner transformation. We obtain the exact results of the minimal energy gap Δ 0 for exciting a fermion quasi-particle, the minimal energy gap Δ h for exciting a hole and the ground state phase diagram under various boundary conditions. The results show that the boundary conditions do not change the quantum phase transition points of the system, but the minimal energy gaps in the cases of periodic and open boundary conditions are quantitatively different. When the dimerized transverse single-ion anisotropies parameter D 1 > D 2 , the ground state is lied in the non-hole systems with arbitrary lattice sites. But if D 1 D 2 , holes will appear in the ground state of system with odd lattice sites.

Planar compact monopole antenna design with triple-band operation for the IEEE 802.16 m worldwide interoperability for microwave access (WiMAX) system is proposed. By adding C- and L-shaped monopole strips to the antenna, excitation of multiresonant modes can approximate the 2.6, 3.5, and 5.5 GHz bands required for WiMAX (IEEE 802.16 m) operations. The obtained impedance bandwidths across the operating bands approach 168/325/1208 MHz for the 2.6/3.5/5.5 GHz bands, respectively. The proposed uniplanar antenna reduces the antenna size by at least 15%, since overall antenna volume is only 22 × 28 × 0.8 mm3 (0.19 λo × 0.243 λo × 0.007 λo, at 2.6 GHz). The measured peak gains and radiation efficiencies approximate 3.0/4.2/4.5 dBi and 77/76/83% in the 2.6/3.5/5.5 GHz band, respectively, and exhibit a nearly omni-directional pattern in the XY-plane.

This paper proposes research schemes for a tricopter based on its developing trend.It focuses on its mechanical structures and physical moments and solves the problem that moments in the system offset each other.Then,it analyzes aircraft attitudes on launching,pitching,rolling and yawing by aerodynamic analysis and establishes a mathematical model for the tricopter.Finally,the PID and Linear Quadratic Gaussian(LQG) control methods are used to design a controller for the tricopter.The results show that the PID method does not achieve the desired states for its long equilibrium time and overmuch oscillations.However,after improving the controller by the LQG method,the simulation experiments on step functions and pulse response functions from different channels show that the response speed of the control has increased,and the balance of control can be implemented by about 2 s.the research can provide theoretical function for controlling aircraft attitudes.

Novel side dams for twin roller continuous casting were fabricated. The side dams were divided into three zones and were prepared with different materials to meet working demands. Al2O3–ZrO2 laminated ceramic was used as a key part to overcome immense friction and wear and frequent thermal impact during the whole casting process. A series of experiments for laminated composite were carried out, and the results indicated that the laminated composite presents rather excellent comprehensive properties including considerable fracture strength and fracture toughness, high critical thermal shock temperature difference and good tribological properties. These superior comprehensive properties are mainly attributed to the special laminated structure with expected residual stress in different layers. Furthermore, the side dams were successfully applied in the twin roller continuous casting in the laboratory. The side dams exhibit good working ability under extremely tough conditions and the steel strips produced by continuous casting present good qualities.

The alternating-bond mixed spin-1/2 and spin-1 Ising chain with both longitudinal and transverse singleion anisotropies are solved exactly by means of a mapping of the spin-1/2 transverse Ising chain and the Jordan-Wigner transformation. The ground state quantities are strongly dependent on the model Hamiltonian parameters J(1), J(2), D(x) and D(z). We obtain the quasi-particles' spectra A(k), the dimerization gap Delta(d), the minimal energy Delta(0) for exciting a fermion quasi-particle, the minimal energy Delta(h) for exciting a hole and the ground state energy E(g). The phase diagram of the ground state is also given. The results show that the alternating bond just quantitatively changes the ground state properties; no matter the nearest-neighbor exchange interactions J(1) and J(2) are equal or not, when D(z) >= 0 for any finite value of D(x) there is no quantum critical point and the ground state is always in a spin ordered phase. (C) 2011 Elsevier B.V. All rights reserved.

By modeling and calculating the piezoelectric ceramic patches of cantilever generators,the effects of different positions of the piezoelectoic patches on the generation ability of the generators were analyzed and the optimum positions of the piezoelectric ceramic patches under the first and second vibration modes were obtained with Euler-Bernoulli model and by testing the open circuit voltages,short-circuit currents of generators and the performance of LED lighting.Experiments indicate that the generators show the optimum performance under the first vibration mode when the piezoelectric ceramic patches locate at the root of the cantilever.Its opening voltage and short current are 4 times and LED power is 10 times of experimental data of other three generators.Moreover,the generation ability is investigated under the second vibration mode.When the ceramic patch respectively locates at the middle and the root of cantilever,the generation ability of the former is superior to that of the latter,and the opening voltage and short current of the former are 1.2 and 1.9 times those of latters respectively through six generator experiments.In addition,LED power of the former is 1.4 times those of the others.It points out that the piezoelectric ceramic patches should be located at the root of beam under the first vibration mode and at the middle of beam under the second mode to improve the generation efficiency.

The mixed spin-1/2 and spin-1 Ising chain with both longitudinal and transverse single-ion anisotropies is solved exactly by means of a mapping to the spin-1/2 Ising chains with alternating transverse fields and the JordanWigner transformation. Within this scheme, the thermodynamic quantities of this model are rigorously determined by a recursion formula derived for the partition function based on the reduced spin-1/2 transverse Ising model. The corresponding thermodynamic properties are calculated and discussed. (C) 2010 Elsevier B.V. All rights reserved.

The dimerized spin-1 Ising chain with both longitude and transverse single-ion anisotropies D(z) and D(x) is solved exactly by means of a mapping to the spin-1/2 Ising chain with the alternating transverse fields and the Jordan-Wigner transformation. The analytical expressions of the quasi-particles' spectra Lambda(k), the minimal energy gap Delta(0) for exciting a fermion quasi-particle , the minimal energy gap Delta(h) for exciting a hole, and the ground-state energy E(g) are obtained. The phase diagram of the ground state is also given. The results show that the system exhibits a series of quantum phase transitions depending on the dimerization strength of the crystal fields, while the quantum critical points are determined exactly. (C) 2009 Elsevier B.V. All rights reserved.

We investigate the Josephson effect in one triple-terminal junction with embedded parallel-coupled double quantum dots. It is found that the inter-superconductor supercurrent has opportunities to oscillate in $4\pi$ period, with the adjustment of the phase differences among the superconductors. What is notable is that such a result is robust and independent of fermion parities, intradot Coulomb strength, and the dot-superconductor coupling manner. By introducing the concept of spinful many-particle Majorana modes, we present the analytical definition of the Majorana operator via superposing electron and hole operators. It can be believed that this work provide a simple but feasible proposal for the realization of Majorana modes in a nonmagnetic system., Comment: 4 pages, 3 figures