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The development of low-cost, high-performance oxygen electrocatalysts is of great significance for energy conversion and storage. As a potential substitute for precious metal electrocatalysts, the construction of efficient and cost-effective oxygen electrocatalysts is conducive to promoting the widespread application of zinc–air batteries. Herein, CoxNiyMOF nanoparticles encapsulated within a carbon matrix were synthesized and employed as cathode catalysts in zinc–air batteries. Co0.5Ni0.5MOF exhibits superior oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) performance and durability. The zinc–air battery assembled with Co0.5Ni0.5MOF as the air cathode exhibits a maximum power density of 138.6 mW·cm−2. These improvements are mainly attributed to the optimized metal composition of the cobalt–nickel alloy, which increases the specific surface area of the material and optimizes its pore structure. Significantly, the optimization of the electronic structure and active sites within the material has led to amplified ORR/OER activity and better zinc–air battery performance. This study underscores the immense promise of Co0.5Ni0.5MOF catalysts as feasible substitutes for commercial Pt/C catalysts in zinc–air batteries. [ABSTRACT FROM AUTHOR]

• Four asymmetrical unfused ring acceptors were designed by end-capped modification. • The designed acceptors have more excellent properties than the reference acceptors. • Functional group substitution outdo halogen replacement in boosting molecular property. • The introduction of thiophene unit can significantly improve the V oc , f and LHE. Non-fused ring acceptors (NFRAs) have garnered significant attention due to their low cost, ease of synthesis, and high efficiency. Molecules with asymmetric structures can improve molecular stacking and effectively reduce non-radiative energy loss. So, the asymmetric A-D1-D2-A series NFRAs (DPCT-4F and DPCT-4Cl) were selected as the research objects, and four acceptors (DPCT-D1∼DPCT-D4) were designed using end-capped modification strategies. Theoretical simulations were conducted on the ground and excited state characteristics of DPCT series molecules, and the electron mobility of the dimers formed by these acceptors was calculated. It was found that the simulated energy levels, energy gaps, absorption spectra and open-circuit voltages of original molecules are consistent with the trends in the experiment, ensuring the accuracy of the calculation method. Moreover, the nearly equal bond lengths of the developed compounds and the original molecules at the corresponding positions indicate that end-capping modification strategies have little effect on the molecular bond lengths. However, the instability of C-C single bond results in an increased dihedral angle between dipyran and cyclopentadithiophene. Among these designed molecules, DPCT-D1 and DPCT-D2, modified with -CN/-NO 2 functional groups, outperform the reference molecules regarding energy gap, molecular descriptors, absorption spectrum, and exciton binding energy. This demonstrates the superiority of functional group substitution strategies with strong electron-withdrawing ability. Introducing thiophene units enables DPCT-D4 molecule to achieve a higher open-circuit voltage, dipole moment and light capture ability. Additionally, all the designed molecules exhibit higher electron mobility than DPCT-4F. DPCT-D1 shows even higher mobility than the better-performing reference molecule DPCT-4Cl due to its greater electronic coupling strength and lower reorganization energy. Overall, most tailored molecules, particularly DPCT-D1, exhibit superior performance in most critical parameters compared to the reference molecules, demonstrating the design strategy's effectiveness and offering worthwhile theoretical instruction for developing high-performance acceptors. [Display omitted] [ABSTRACT FROM AUTHOR]

Sensorless schemes are mainly used in fault-tolerant control of interior permanent magnet synchronous motor (IPMSM) drives. Traditional sensorless methods with injection of high-frequency (HF) carrier signals into the stationary reference frame have a stable performance. However, phase shifts caused by conventional high-pass filters (HPFs) decrease the estimation accuracy. Besides, the demodulation process is usually complicated, which increases the difficulty of application. To solve these problems, this study presents an HF-induced current direct demodulation method. Rotor position angle can be solved from the sampled currents at adjacent moments without demodulation signals. Therefore, the errors related to filters in the rotor position estimation are eliminated. Besides, the efficiency of the demodulation algorithm is improved. Furthermore, an online compensation method for cross-saturation effect is proposed. Experimental results verify that the proposed strategy can obtain an accurate rotor position with good steady-state and dynamic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Five non-fully-fused ring acceptors were designed by end-cap modification strategy. • The various characteristics of original and designed molecules were compared. • The designed acceptors have more excellent properties than the reference acceptor. • Functional group substitution outdo halogen replacement in boosting molecular property. End-capped modification is an efficacious strategy for developing high-performance acceptor materials. In this paper, the experimentally synthesized A-D-A'-D-A type non-fully-fused ring acceptor IDTBT-4F (R) was used as a reference molecule, and five small molecule acceptors for R1-R5 were investigated by changing R's terminal functional groups. By using DFT/B3PW91/6-31G (d,p) method, the ground-state structures of all molecules were studied. The absorption spectra of these acceptors were gained by the TD-DFT/MPW1PW91/6-31G (d,p) approach. Meanwhile, the charge density difference and transition density matrix were analyzed effectively. It can be observed that, compared to the R molecule, all developed molecules exhibited narrower energy gaps, larger absorption wavelengths, more red-shifted absorption spectra, lower excitation energies, higher dipole moment and greater electron-accepting capacity. The strategy of functional group substitution is superior to halogen substitution in improving the aforementioned parameters. Both terminal π-extension and end-group chlorination strategies can synergistically enhance molecular performance. In addition, we also calculated the electron mobility of the dimers constructed by all the molecules, among which R1 and R4 molecules designed with –COOCH 3 functional group substitution and R2 molecule with terminal chlorination achieved superior electron mobility compared to R molecule due to their significant electronic coupling. Overall, the study shows that the designed molecules can be highly effective candidates for applications of organic solar cells. [ABSTRACT FROM AUTHOR]

In order to improve the performance of interior permanent magnet synchronous machine (IPMSM) based on space voltage vector modulation schemes, this paper presents a highly accurate online method to find the proper maximum-torque-per-ampere (MTPA) angles. This algorithm fully considers the nonlinear characteristics of the d-axis inductance, q-axis inductance, and permanent magnetic flux together. Additionally, the influences of temperature are taken into account. In this paper, the proposed method injects a small virtual angle signal into the current angle mathematically to track the stator current reference angle that is close to real MTPA points. Moreover, following a theoretical analysis method, the error of the virtual signal injection method is analyzed. Then, based on the results of error analysis, this paper proposes a compensation strategy that can significantly reduce the current angle error between the tracking point and real MTPA point. At last, various experiments on an IPMSM test bench verify the proposed control technique and overall performance. [ABSTRACT FROM AUTHOR]

Three-phase interior permanent magnet synchronous motor (IPMSM) drive systems have gotten widely used recently in various applications due to their speed regulation characteristics and high power density. Compared with classical field-oriented control (FOC) and flux-weakening control, model predictive control (MPC) technique is more efficient and effective in achieving excellent performance without complicated controller tuning, but with explicit constraints. Yet, the optimum application of the MPC algorithm in a machine control system is still in the exploratory stage. In order to lower the current and torque ripples, this paper retains a modulator, but replaces all the proportional integrate control loops, which are contained in the conventional FOC systems with a single MPC controller. Moreover, we adopt a brand-new linearization approach to tackle the strong coupled nonlinear IPMSM mathematical model, obtaining an improved linear plant model, which is suitable for the motor with constant load torque. When it comes to flux-weakening control, the required d-axis current is calculated, after which it is used as the input of the proposed MPC controller, abandoning the previous natural field weakening method. Finally, for the purpose of lowering the dynamic speed and current overshoot, a further constraint in the change rate of manipulated variables is discussed. The improved control algorithm has been verified in both simulation and experiment. [ABSTRACT FROM AUTHOR]

Abstract: An unprecedented substrate‐dependent [5+1] annulation of 2‐isocyanochalcones with nitroalkanes was developed for the efficient synthesis of functionalized quinolines and 3‐nitrodihydroquinolines. This transformation delivers both the aromatic and dihydroquinolines by selectively elimination or retention of the nitro group. Moreover, 3‐nitroquinolines and tricyclic pyrrolo[2,3‐c]quinolines were conveniently constructed from the resulting 3‐nitrodihydroquinolines through a single operation, respectively. [ABSTRACT FROM AUTHOR]

Two {AsO 2 (OH)}-bridging lanthanide(Ln)-incorporated arsenotungstates (ATs) [H 2 N(CH 3 ) 2 ] 8 LnNa 5 {[W 3 Ln 2 (H 2 O) 8 AsO 8 (OH)][B-α-AsW 9 O 33 ] 2 } 2 ·65H 2 O [Ln = Er III ( 1 ), Yb III ( 2 )] were synthesized by reaction of Na 2 WO 4 ·2H 2 O, Ln(NO 3 ) 3 ·6H 2 O and NaAsO 2 in the presence of dimethylamine hydrochloride. The common structural features of 1 and 2 are that the As III ions not only act as heteroatoms of the AT fragments but also function as the bridging groups to link two identical {[W 3 Ln 2 (H 2 O) 8 AsO 8 (OH)][B-α-AsW 9 O 33 ] 2 } half-units. The results of TG analyses indicate that 1 and 2 undergo the similar three-step weight loss procedure between 25 and 800 °C. The first-step weight loss is attributable to the liberation of sixty-five lattice water molecules, the second-step weight loss corresponds to the release of sixteen coordination water molecules, ten protons as well as eight dimethylamine groups, and the third-step weight loss can be assigned to the sublimation of three As 2 O 3 molecules. In addition, the solid-state photoluminescence properties of 1 and 2 have been investigated and mainly demonstrate the characteristic emission behaviors of Er III ions and Yb III ions. [ABSTRACT FROM AUTHOR]

This article investigates the use of nickel electroplated carbon fiber (Ni‐CF) fabric to enhance the electromagnetic interference (EMI) shielding capability of carbon fiber reinforced thermoplastics (CFRTs), particularly for automotive and aerospace applications. The study examines the influence of nickel electroplating parameters of carbon fiber on the morphologies of carbon fiber fabrics. Ni‐CF reinforced polyamide 6 (Ni‐CF/PA 6) was prepared by the film‐stacking method. The flexural properties analysis demonstrates a 21.1% increase in flexural strength for Ni‐CF/PA 6 composites compared to as‐received carbon fiber reinforced PA 6 (CF/PA 6) composites. Additionally, the introduction of nickel layer significantly improves the EMI shielding efficiency of CF/PA 6 composites, with the average shielding efficiency increasing from 23.5 to 31.6 dB within the X‐band and Ku‐band frequency ranges. Scanning electron microscope (SEM) analysis confirms that the nickel layer enhances the interfacial bonding between the PA 6 matrix and the Ni‐CF, which is attributed to the micro cone‐shaped structures of the nickel layer. Overall, the electroplating method effectively modifies the carbon fiber surface, resulting in composite laminates with enhanced mechanical properties and superior EMI shielding efficiency. These findings provide valuable insights for the development of advanced carbon fiber reinforced composites with improved functionalities in various applications. Highlights: The electroplating method is used to process the nickel electroplated carbon fiber fabrics.The introduction of micro cone‐shaped structure nickel on the fiber surface by electroplating provides the mechanical interlocking between carbon fiber and matrix.The nickel electroplated carbon fiber can significantly increase electromagnetic interference shielding capability of carbon fiber reinforced thermoplastic composites. [ABSTRACT FROM AUTHOR]

Electrospinning has become a widely-used method for fabricating polymer nanofibers for various applications including filtration, drug delivery, and tissue engineering. Due to the high extensional forces during the electrospinning process, and the rapid crystallization and solidification during solvent evaporation, molecular orientation may develop within the resulting fibers. The properties of electrospun fibers are expected to be sensitive to level of orientation in the fibers. Various reports have shown an increased modulus with decreased fiber diameter, and molecular orientation has been used to explain this trend. However, there have been relatively few studies of the detailed relationship between fiber diameter and molecular orientation, especially at the single fiber level. Here we report a quantitative study of the orientation in individual electrospun poly(caprolactone) (PCL) and poly( l -lactic acid) (PLLA) fibers using low-dose electron microscopy and diffraction techniques. Our results confirmed that for electrospun fibers of PCL and PLLA processed under similar experimental conditions, the molecular orientation decreased as the fiber diameter increased. The extent of orientation remained high for quite large fiber diameters, with azimuthal orientation of 20° seen up to ∼500 nm for PCL and ∼2000 nm for PLLA. [ABSTRACT FROM AUTHOR]

A novel welding tool with a double pin structure was proposed to solve the problem of difficult weld formation with a large depth to width ratio (DWR). Experiments revealed that the novel welding tool could achieve non-defect joints for four common engineering aluminum alloys (2A12-T6/5052-H32/6013-T6/7075-T6), with a DWR of 0.59–0.67. Due to the difference in the direction of material flow between the upper pin and the pin effect, impact slow flow zone was formed in the joint center. The maximum ultimate tensile strength of the 7075-T6 aluminum alloy double pin friction stir welding (DPFSW) joint reached 450.38 MPa, which was 85.8% of the base material. Analysis of the tensile fracture location revealed that the stirring zone of the advancing side and weld nugget zone occurred local blockage, resulting in joint failure. • In this paper, a novel welding tool with a double-pin structure is proposed, and it is demonstrated through experiments that the novel welding tool can achieve defect-free joints with DWR of 0.59–0.67 for four common engineering aluminum alloys. • The DPFSW joint can be divided into seven zones, where the ISFZ is caused by the different flow directions of the upper and lower layers of the DPFSW material, and the interior of this zone consists of a mixture of fine and coarse grains. • DPFSW joints are greatly influenced by the welding speed. At a welding speed of 100 mm/min, the joint strength was the highest, reaching 450.38 MPa, or 85.8% of BM. [ABSTRACT FROM AUTHOR]

ABSTRACT Electrospun poly(vinylidene fluoride) (PVDF) nanofibers were collected on aluminum foil across a gap with widths that varied in size from 2 to 10 mm. Scanning electron microscopy (SEM) images on fiber bundles showed that in all cases, fibers in the gap were macroscopically aligned across the gap. However, single fiber selected area electron diffraction (SAED) patterns and polarized Fourier Transform Infrared (FTIR) spectra demonstrated that fibers deposited across the gap were also highly aligned at the molecular level with the polymer backbones oriented along the fiber axis and that the extent of molecular orientation increased with the gap width. A possible explanation for this observation is based on the repulsion of similarly charged nanofibers and the simultaneous attraction of these fibers to the oppositely charged gap edges. This provides a plausible model for understanding the deposition kinetics and subsequent molecular orientation as a function of gap size when electrospinning using this method of fiber collection. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 617-623 [ABSTRACT FROM AUTHOR]

Brushless permanent magnet (BLPM) motor drives based on Hall sensors have received extensive attention in the literature and are widely used in many applications. However, most of the available and published controllers assume that the Hall signals are always available, which is not true if any of the sensors are faulted. In this paper, several fault-tolerant control schemes for BLPM motor drives are proposed. The methodology is based on fault diagnosis and its classification, and subsequent signal reconstruction. Simulation and experimental results demonstrate the effectiveness and advantages of the proposed fault-tolerant schemes in restoring the motor operation when failures occur in up to two Hall sensors. The proposed fault-tolerant schemes can be easily and flexibly realized for conventional drive systems, either by adding the code in the existing driver or by adding a simple auxiliary circuit between the Hall sensors and the driver. [ABSTRACT FROM PUBLISHER]

In order to further improve the hydrogen production efficiency of microwave liquid-phase discharge, a three-electrode reactor was designed and a suspended electrode was added. The internal structure of the three-electrode reactor was optimized. The formation of bubbles during the discharge and the change characteristics of plasma morphology were studied after adding the suspended electrode. In addition to investigating the physical influence of the suspended electrode on the discharge plasma, the influences of the different electrode materials and specific surface area of the suspension electrode on the composition of the gas products, the hydrogen flow rate and the hydrogen energy yield were also investigated. The experimental results show that the suspended electrode can increase the formation time of plasma and bubble. In this study, the highest flow rate of total gas is 29.5 NL/min with the 80 PPI-Cu foamed metal suspended electrode which is an increase of 31.5% than no suspended electrode. • Suspended electrode with high specific surface area is used. • The effect of suspended electrode on bubble residence time is discussed. • The energy yield of hydrogen production increased by 34.6%. [ABSTRACT FROM AUTHOR]

Well-defined probes based on rare earth complexes were prepared by using europium oxide (Eu2O3), gadolinium oxide (Gd2O3), 2-thenoyl trifluoroacetone (TTA), and 1,10-phenanthroline monohydrochloride monohydricrate (phen) as raw materials. Fluorescence spectroscopy was used to determine that 1:1 is the optimal ratio of Eu3+ and Gd3+. So a Eu0.5Gd0.5(TTA)3phen/PMMA temperature sensitive paint was prepared composed of rare earth complexes Eu0.5Gd0.5(TTA)3phen as probe molecules and polymethyl methacrylate (PMMA) as the matrix. The as-prepared Eu0.5Gd0.5(TTA)3phen/PMMA exhibits a strong emission at 617 nm and has fine temperature quenching properties in the range of 20 °C–90 °C. Furthermore, the rate of change of luminescence and temperature sensitivity are enhanced due to doping of Gd3+, illustrating a synergistic effect between Gd3+ and Eu3+. [ABSTRACT FROM AUTHOR]

Abstract: In order to optimize the double-clad fiber laser system, the laser output power should be as large as possible and the systemic cost should be as cheap as possible under the condition of the optimum fiber length. In this work, the improved approximate analytical solutions of the optimum fiber length and the laser output power are obtained based on the model of linear cavity strongly pumped Yb-doped double-clad fiber laser. And the effects of the laser scattering loss, the pump power, Yb dopant concentration, and the reflection coefficients of the input and output mirrors at laser wavelength on the laser output power and the optimum fiber length are discussed and analyzed in detail. Thereby the optimal laser system can be determined. [Copyright &y& Elsevier]

Abstract: An improved shooting algorithm for high-power fiber laser is proposed based on the relation of the two-end boundary laser powers. By the improved shooting algorithm, the evolutions of the pump and laser powers along the fiber position for Yb-doped and Tm-doped high-power double-clad fiber lasers with the laser scattering loss are analyzed. The results prove that the improved shooting algorithm can be efficient even if the pump power is up to kilowatt level, and the initial value can all be fast convergent as long as the initial guessed laser power is smaller than the truth value. So, this improved shooting algorithm can be used in high-power double-clad fiber lasers efficiently. [Copyright &y& Elsevier]

Abstract: In order to improve the performance of the double-clad fiber laser, the optimum laser length needs to be estimated prior to the experiment. Previous expressions for the optimum length of fiber laser have been established under some assumptions, such as the output power without laser scattering loss and the pump power without reflection in the output-end. In this work, the issue of optimum laser length has been analyzed theoretically based on the strongly pumped fiber laser model. An extended expression for the optimum length of the linear cavity Yb3+-doped double-clad fiber laser is obtained. The respective effects of the laser scattering loss, the pump power, the Yb3+ dopant concentration, and the pump reflection on the optimum laser length are identified. [Copyright &y& Elsevier]

[Display omitted] • Hook feature was eliminated by enlarged pin, which ensured the interface stability. • The interface composed of laminated IMCs structure was beneficial to the mechanical properties. • Four different interface failure modes were firstly found and established during the shearing process. A novel welding tool, characterized by the enlarged pin design was developed to solve the hook feature or insufficient interface deformation for Al/steel friction stir lap welded joints. The welding tool enhanced the interface deformation effect and eliminated hook feature. The thickness of the intermetallic compound (IMC) layer at the interface decreased from 3.3 μm to 0.46 μm, when the welding speed increased from 30 mm/min to 300 mm/min. The laminated structure composed of IMCs and fine steel grains gradually disappeared, with the interface gradually changing from serrated to straight as welding speed increased. The nanohardness value of the microstructure reached 9.4 ± 0.3 GPa at a distance of 10 μm from the interface layer. Due to the larger metallurgical bonding area, the best line load 499.4 N/mm reached 52 % of the 3 mm 6082-T6 alloy, which was obtained at the rotational speed of 1200 r/min and the welding speed of 50 mm/min. Four different interface failure modes were found and established during the shearing process. The strain concentration phenomenon of the successive occurrence, development and transfer of interface failure presented obvious interval characteristics in time and space. [ABSTRACT FROM AUTHOR]

Abstract: The radially polarized partially coherent Laguerre–Gaussian (LG) beam is introduced and its paraxial propagation properties are studied. The effect of propagation parameters on the intensity distribution, the beam quality, the polarization property and the coherent property of the beam is illustrated analytically and numerically. It is shown that in free space the correlation length has a significant influence on the intensity profile and the degree of polarization. [Copyright &y& Elsevier]

[Display omitted] • MWCNT formed an interwoven layer on the t-ZnO via self-assembly and thus constructed a three-dimensionally (3D) conductive network in shape memory PLLA/TPU scaffold. • 3D porous bone scaffold was fabricated via SLS. • The construction of 3D conductive network enhanced the electro-actuated shape memory properties of scaffold. • The osteogenic inductivity of the scaffold improved with the synergistic effect of electrical stimulation (ES) and t-ZnO. The electro-actuated shape memory polymer scaffold has gained increasing attentions on the utilization of minimally invasive surgery for bone defect repair, which requires to construct an efficient conductive network to accomplish electrical-to-thermal conversion from conductive fillers to the entire matrix evenly. In this study, multiwall carbon nanotube (MWCNT) was convective self-assembled on the ZnO tetrapod (t-ZnO) template, where MWCNT was controlled to disperse uniformly and regulated to contact with each other effectively due to the immersion capillary force during the evaporation loss of the convective self-assembly process, leading to an interwoven layer on the t-ZnO surface. The prepared t-ZnO@MWCNT assembly was embedded in the poly(L-lactic acid)/thermoplastic polyurethane (PLLA/TPU) scaffold fabricated via selective laser sintering to construct a 3D conductive MWCNT network for improving the electro-actuated shape memory properties. It was observed that the interconnected MWCNT formed a 3D conductive network in the matrix without significant aggregation, which boosted the electrical-to-thermal properties of the scaffold, and the scaffold containing t-ZnO@MWCNT assembly possessed better electro-actuated shape memory properties with shape fixity of 98.0% and shape recovery of 98.8%. The scaffold exhibited improved electro-actuated shape memory properties and mechanical properties and the osteogenic inductivity was promoted with the combined effect of t-ZnO and electrical stimulation. [ABSTRACT FROM AUTHOR]

The medium-thick Al/Mg dissimilar friction stir welding (FSW) joint has serious groove and cavity defects due to uneven thermal distribution in the thickness direction. The submerged friction stir welding (SFSW) was employed to decrease the peak temperature of the joint and control the thermal gradient of the thickness direction, which were beneficial in suppressing the coarsening of the intermetallic compounds (IMCs) layer and improving the weld formation. According to the SEM results, the thickness value of the IMC layer in the nugget zone and shoulder affect zone decreased from 0.78 μm and 1.31 μm in FSW process to 0.59 μm and 1.21 μm in SFSW process at the same parameter, respectively. Compared with the FSW process, SFSW improves the thermal accumulation during the process, which inhibits the formation of the IMCs and facilitates the material flow to form a mechanical interlocking structure. This firm interface formation elevates the effective contact area of the whole joint interface and provides a strong connection between the dissimilar metals. Thus, the ultimate strength of the 6 mm thick Al/Mg dissimilar SFSW joints was enhanced to 171 MPa, equivalent to 71.3% of AZ31B Mg alloys strength. [ABSTRACT FROM AUTHOR]

Abstract: A series of vinylogous thiol esters 2 , 3 and 2,6-dioxo-1,2,5,6-tetrahydropyridines (cyclic vinylogous thiol esters) 4 were prepared in high to excellent yields from the tandem reaction of readily available α-alkenoylketene diethylthioacetals 1 and diethyl malonate. A plausible mechanism, which involves a base catalyzed retro-Michael ring opening of cyclohexanenes 2 to give vinylogous thiol ester 3, is disclosed. [ABSTRACT FROM AUTHOR]

Due to the unbalanced three-phase currents and the torque ripples and speed fluctuations to the drive caused by the current sampling errors of three-phase current sensors and corresponding signal processing circuits, the estimation on current sampling errors is of great importance to eliminate these adverse effects. The observer-based methods, however, present two defects: first, they could increase the computational burden to the drives, thus limiting their practical applications; second, their high dependence on the system speed or position feedback information might degrade the estimation accuracy. To solve these problems, this article proposed a fixed-point sampling method of lower branch flows and three phase-currents, which adopts the relations between the measured currents, rather than any complex algorithm, to estimate the current sampling errors. To coordinate with the proposed strategy, a fixed-point sampling scheme was accordingly rolled out. Compared with the observer-based methods, as a fixed-point one, much applicable to actual digital controllers, it could reduce the computational burden of the drive. Meanwhile, its effectiveness was verified by experimental results on a 1.5-kW IPMSM prototype, which showed accurate estimated current sampling errors and the effectively eliminated torque ripples and speed fluctuations. [ABSTRACT FROM AUTHOR]

The conventional phase current reconstruction strategies utilize a dc bus current sensor to reproduce the three-phase currents during phase current sensor faults. However, no current sensor is guaranteed to be healthy in an actual drive. It means that the only survived current sensor may not be accidentally located at the dc bus side, and it can also be at the phase side. In addition, previous studies focus on a particular inverter topology for current reconstruction, whose fault-tolerant capability is threatened when the inverter topology is changed due to malfunctions. This article proposes a survivable interior permanent magnet synchronous motor (IPMSM) drive that realizes the current reconstruction purpose whichever the only survived current sensor is. Besides, inverter topology reconfiguration can be realized by not changing the wirings of the current sensors. Most important of all, the proposed strategy does not affect the normal operations of the drive when no fault occurs. The effectiveness of the proposed strategy is verified by experimental results on a 5-kW IPMSM motor prototype, which shows that the reconstructed phase currents track the actual ones accurately under different failure conditions. [ABSTRACT FROM AUTHOR]

The precision of position estimation is highly dependent on the accuracy of multiple current sensors, whereas the conventional error calibration strategies for current sensor accuracy uncertainty (SAU) problem have limitations regarding the position sensorless controlled drives. In order to solve this thorny problem, this article proposes a mutual calibration strategy for the multiple current sensors in an interior permanent magnet synchronous motor (IPMSM) drive. The proposed current sensor error calibration strategy takes full advantage of the correlation among the multiple current sensors themselves without using any complicated observers. Moreover, the traditional seven-segment space vector pulsewidth modulation technology is applied without modification. The only change is reflected in several sets of the artificially added current sampling points. The effectiveness of the proposed strategy is verified by experimental results on a 5-kW IPMSM motor prototype, which shows that the calibrated current sensors exhibit improved accuracy, and the position estimation accuracy is also guaranteed. [ABSTRACT FROM AUTHOR]

• The diffusion of severe plastic deformation is 103 faster than thermal activation. • Amorphous structures exist at the interface layer. • Proposed a formula for predicting the thickness of the Fe-Al IMCs layer. The severe plastic deformation (SPD)-induced atom rapid diffusion joining method was employed to increase Al/Fe diffusion rate at short time and low temperature, and achieve reliable metallurgical bonding. The local stress and strain caused by SPD led to the refinement of crystal grains and the generation of high concentrations of dislocations, which provided channels for the rapid diffusion of Fe atoms to the Al interface region. The diffusion rate of the interface layer is 103 faster than the thermal activation diffusion state. The short-term and low-temperature characteristics of the SPD-induced rapid diffusion method can be extended to other solid-state welding methods. [ABSTRACT FROM AUTHOR]

A simple citric acid (CA)‐ammonium molybdate co‐impregnation method was applied to prepare the Mo‐based MCM‐49 catalyst to ameliorate the dispersion of metallic Mo for methane dehydro‐aromatization reaction (MDA). The newly prepared catalyst has higher crystallinity and maintains the original morphology of zeolite, which proves that the addition of citric acid will not destroy the basic structure of the catalyst. Based on H2‐TPR, UV‐vis, NH3‐TPD and XPS characterization results, it can be corroborated that the introduction of citric acid changes the coordination state of Mo element. Brønsted acid sites can stabilize the monomeric Mo oxide species by increasing MoOx migration into the MCM‐49 zeolite pores channel after calcination, which may affect the distribution of active sites MoCx and thus improve MDA catalytic activity. The experimental results show that the Mo‐based MCM‐49 catalyst with nCA : nMo ratios of 1.0 has higher methane conversion (14.5 %) and aromatics yield (9.8 %). The combination of XPS, TG and Raman tests of the spent catalyst confirms that the newly synthesized catalysts produce less carbon deposition, thus improving the catalytic durability during the MDA reaction. [ABSTRACT FROM AUTHOR]

Purpose: Rice Therapy (RT) was created to process clients' life stressors. Two trainings were delivered at two geographically different sites (E1 and E2) in China for testing the benefits of RT in social work. Methods: E1 participants (n = 42) were directed to recall happiness in their rice artwork creation, while this keyword was not given in E2 (n = 88). The organizing agency in each site collected evaluation data after training through an anonymous e-survey including two individualized rating scales on retrospective pre- and immediate post-RT mood self-assessment and three open-ended questions on the potentiality and limitations of applying RT in social work practice. These secondary data were analyzed with a bi-experimental comparison design. Results: Both groups showed post-RT mood improvement, with E1 (directive) participants generating greater improvement than E2 (nondirective) participants. A mixed between-within-subjects analysis of variance showed insignificant interactive effects between groups on the participants' mood scores, meaning that directive and nondirective approaches to artwork creation produced similar outcomes. Overall comments addressed three themes: 1) benefit of using rice; 2) RT effectiveness; 3) evaluation of RT as a practice platform. Discussion: RT benefits should be further tested with instruments measuring the various contributing factors of this positive approach to stress reduction. [ABSTRACT FROM AUTHOR]

The current reconstruction strategies using single current sensor in the motor drives are widely researched. However, the sampled currents do not represent the average values within the modulation period, especially for the asymmetric modulation or asymmetric sampling solutions. This is due to the following two reasons: 1) The detected current values obtained at different sampling points are utilized to calculate the three-phase currents; and 2) the detected instantaneous currents are applied to estimate the average current values. In this letter, the current change rates under different action vectors are estimated to compensate these errors in a three-phase four-switch interior permanent magnet synchronous motor (IPMSM) drive with single current sensor. The effectiveness of the proposed strategy is verified by experimental results on a 5-kW IPMSM motor prototype, which shows that the current reconstruction errors are reduced after compensation. [ABSTRACT FROM AUTHOR]

This paper proposes a new phase current reconstruction scheme without using null switching states for interior permanent magnet synchronous motor (IPMSM) sensorless control. The phase currents are independently reconstructed and no additional test voltage pulses are required. First, the principle of the basic phase current reconstruction for IPMSM drive system is analyzed in detail. Then, an independent phase current reconstruction scheme without using null switching states is proposed. The current reconstruction dead zone is divided into six sectors, and each sector is split into three parts with corresponding vector synthesis methods. Meanwhile, the null switching states, V000 and V111, are removed from the proposed scheme. In this case, the zero vector is synthesized by the other available vectors. Finally, the reconstructed three-phase currents are utilized for high frequency sine-wave voltage injection-based position estimation. The effectiveness of the proposed scheme is verified by experimental results on a 5 kW IPMSM motor prototype, which shows that the reconstructed phase currents track the actual currents accurately under different working conditions. [ABSTRACT FROM PUBLISHER]

• Single Mn atom anchored C 3 N monolayer for CO oxidation has been studied. • The Mn in the N vacancy of C 3 N is stable under 400K base on MD simulations. • The preferable adsorption of the O 2 avoids the CO poisoning on Mn@ C 3 N. • The easily O 2 dissociation on Mn@ C 3 N benefits the further CO oxidations. In this study, the use of a single Mn atom anchored to a nitrogen vacancy in a C 3 N monolayer (Mn@C 3 N) for CO oxidation is investigated using first-principles calculations. The stability of Mn@C 3 N is confirmed through the analysis of binding energy, the movement of the Mn atom within the N vacancy, and ab initio molecular dynamics simulations at 400K for a period of 6 ps. O 2 is found to have more favorable adsorption on Mn@C 3 N compared to CO, and the direct dissociation barrier for O 2 is only 0.69 eV. The Eley-Rideal (ER) and Langmuir-Hinshelwood (LH) mechanisms are also examined on the Mn@C 3 N, and it is found that the ER mechanism was preferred due to its lower rate limiting barrier (0.57 eV compared to 0.91 eV for the LH mechanism). In addition, the oxidation of CO by the leftover O atom on the Mn@C 3 N is found to be facile, with a small barrier of 0.05 eV via the ER mechanism. These findings provide insight into the potential of the Mn@C 3 N as a single-atom catalyst for CO oxidation at low temperatures. [Display omitted] Mn@C3N monolayer with N vacancy for CO oxidation [ABSTRACT FROM AUTHOR]

Plasmonic gold (Au) and Au-based nanocatalysts have received significant attention over the past few decades due to their unique visible light (VL) photocatalytic features for a wide variety of chemical reactions in the fields of environmental protection. However, improving their VL photocatalytic activity via a rational design is prevalently regarded as a grand challenge. Herein we boosted the VL photocatalysis of the TiO2-supported Au-Cu nanocatalyst by applying O2 plasma to treat this bimetallic plasmonic nanocatalyst. We found that O2 plasma treatment led to a strong interaction between the Au and Cu species compared with conventional calcination treatment. This interaction controlled the size of plasmonic metallic nanoparticles and also contributed to the construction of AuCu-TiO2 interfacial sites by forming AuCu alloy nanoparticles, which, thus, enabled the plasmonic Au-Cu nanocatalyst to reduce the Schottky barrier height and create numbers of highly active interfacial sites. The catalyst's characterizations and density functional theory (DFT) calculations demonstrated that boosted VL photocatalytic activity over O2 plasma treated Au-Cu/TiO2 nanocatalyst arose from the favorable transfer of hot electrons and a low barrier for the reaction between CO and O with the construction of large numbers of AuCu-TiO2 interfacial sites. This work provides an efficient approach for the rational design and development of highly active plasmonic Au and Au-based nanocatalysts and deepens our understanding of their role in VL photocatalytic reactions. [ABSTRACT FROM AUTHOR]

The rare earth ion (Y3+ and Er3+) doped Eu(TTA) 3 phen/PMMA temperature sensitive paint(TSP) was fabricated respectively via free radical polymerization. The as-prepared TSP exhibited a strong red-light emission with good temperature quenching properties in the range of 20–80 °C and the doping of Y3+ and Er3+ could enhance the change rate of the fluorescent intensity and the sensitivity of temperature measurement sensitivity via a synergistic effect. [Display omitted] • Rare earth ion (Y3+ or Er3+) doped Eu(TTA) 3 phen/PMMA were fabricated respectively via free radical polymerization by using the rare earth iron (Y3+ or Er3+) doped Eu(TTA) 3 phen as probe molecules and PMMA as matrix. • The as-prepared TSP of Eu 0.5 Y 0.5 (TTA) 3 phen/PMMA and Eu 0.5 Y 0.5 (TTA) 3 phen/PMMA exhibited a strong red-light emission and good temperature quenching properties in the range of 20–80 °C. • The rare earth ion Y3+ or Er3+ can enhance the change rate of the fluorescent intensity and the temperature measurement sensitivity via a synergistic effect. The temperature sensitive paint (TSP) technology is widely used in the temperature distribution measurement of large area solid field, especially for the in-depth research in the mechanical behavior of complex flow gas around the aircraft, because of its advantages of non-contact, full-field measurement, easy manufacture and use. In this work, we synthesized the rare earth ion(Y3+, Er3+) doped Eu(TTA) 3 phen/PMMA temperature sensitive paint respectively based on the probe molecules of the rare earth ion (Y3+, Er3+) doped Eu(TTA) 3 phen and polymethyl methacrylate(PMMA). The structure of probe molecules and the fluorescent properties of TSP were also studied. The result show that the optimal ratio of Eu3+:Y3+ (or Er3+) is 0.5:0.5, rare earth ions are coordinated with ligands and the doping of Y3+ and Er3+ do not affect the structure of Eu(TTA) 3 phen. Y3+ and Er3+ have gain effect on the fluorescent emission of Eu(TTA) 3 phen/PMMA and the strongest fluorescent intensity (616 nm) is decreased with the increasing of temperature, which show that the Y3+ and Er3+ doped Eu (TTA) 3 phen/PMMA have temperature quenching properties in the temperature range of 20–80 °C. What's more, the doping of Y3+ and Er3+ can improve the change rate of the fluorescent intensity and the temperature measurement sensitivity. [ABSTRACT FROM AUTHOR]

Natural gas is considered to be an important energy and hydrocarbon feedstock. To overcome the harmful combustion of natural gas and convert it to high-value-added products, the development of efficient and stable catalysts via methane dehydroaromatization (MDA) is needed. Here, we use nano α-MoO3 to modify the MCM-22 zeolite for MDA, achieving a 13.3% methane conversion and a 9.1% yield of aromatics. Compared with commercial MoO3, the α-MoO3 modified MCM-22 possesses more Mo species in the zeolite pores, showing a higher catalytic activity, more MoCx active sites during MDA, exhibiting a higher benzene selectivity, and fewer Brønsted acid sites, leading to a strong anti-carbon deposition ability. [ABSTRACT FROM AUTHOR]

Hydrothermal reaction of silver nitrate and a tetraphosphonic acid (H8L) affords a novel coordination polymer, with the general formula, [Ag10(H3L)2(H2O)2(4,4′-bipy)], denoted as compound 1. It is built from extended ⋯Ag–O–P–O⋯ chains and organic linkers to form a 3D network. In its structure, three of four phosphonyl groups of the organic ligand are protonated, endowing compound 1 with rich Brønsted acid sites. With Brønsted and Lewis acidic sites, the catalytic activity of 1 was investigated through cycloaddition reaction of CO2 and epoxides, and the results displayed an excellent performance. Besides, the heterogeneous nature of compound 1 was proved by five cycle experiments with no significant compromise on the activity, indicating the silver phosphonate as an excellent catalyst for CO2 chemical fixation. [ABSTRACT FROM AUTHOR]

A voltage balancer remains a good solution of power transfer for bipolar dc grids, which, however, would increase the costs due to its requirement for additional hardware support. In this article, an auxiliary power transfer strategy is proposed by using the inactive motor drives affiliated with the bipolar dc grid. During idle periods of the motor drive, one inverter bridge arm is connected with the bipolar dc grid at their neutral points, allowing bidirectional power transfer between the upper and lower dc-bus sources. The proposed strategy share part of the voltage balancer's power transfer burden without requiring additional hardware and affecting the normal operations of the motor drive. In addition, its effectiveness is verified by experimental results on an interior permanent magnet synchronous motor drive, showing that the power flows among the upper and lower dc-bus power supplies are controlled effectively. Also, the active control of the dc-bus voltages could be achieved by modulation of the phase currents. [ABSTRACT FROM AUTHOR]

Friction stir lap welding (FSLW) has advantages on obtaining dissimilar upper polymer and lower aluminum materials joint (polymer/Al joint), and how to heighten the bearing capacity of polymer/Al joint as much as possible is greatly meaningful for the manufacturing industries. In this study, choosing dissimilar polyamide 6 (PA 6) polymer and 6061-T6 aluminum alloy materials as research object, traditional FSLW, stationary shoulder assisted FSLW (SSFSLW) and ultrasonic-stationary shoulder assisted FSLW (U-SSFSLW) processes were compared to understand the mechanism of ultrasonic enhancement on the polymer/Al joint. Firstly, the surface morphologies were studied. Then the analyses of micro/macro-structures, mechanical properties and fracture features were carried out by optical microscopy, scanning electron microscopy, differential scanning calorimetry, X-ray diffraction and tensile tests. Results showed that the lap shear failure load of polymer/Al joint by U-SSFSLW reached 1502 N from 814 N by traditional FSLW, because the addition of ultrasonic avoided the bulged-nodule structures on top surface and the cavity defect in stir zone (SZ), broke the Al anchor in upper plate, enlarge the width of SZ in lower plate, and made the deeper micro-pits and larger dents at the interface between SZ bottom and lower plate. The U-SSFSLW process provides an effective way to fabricate the high-strength hybrid joint of dissimilar upper polymer and lower Al materials. [ABSTRACT FROM AUTHOR]

The conversion of low-grade heavy oil into value-added chemicals has garnered significant attention. Plasma is a potentially cleaner, environmentally friendly, and faster method of cracking heavy oil. In this work, ethanol-assisted cracking of hexadecane, a model compound of heavy oil, to produce valuable light fuels such as syngas, C 2 hydrocarbons, and gasoline was investigated under ambient conditions using liquid-phase pulsed-discharge plasma. The gas, liquid, and solid products formed by cracking were analyzed in detail. Single discharge energy and discharge time were the key influences on the cracking reaction. The increase in single discharge energy improved gas and light hydrocarbon yields and inhibited the production of heavy materials, with the maximum gas generation flow rate of 96.1 mL/min. Prolonging the discharge time did not significantly affect the light product selectivity (>97 %). The energy consumption of the reaction was also evaluated and showed a low level of energy consumption. At a single discharge energy of 2.28 mJ and a discharge of 15 min, it obtained 129.9 mg of light hydrocarbons, 13.6 % n-hexadecane conversion, 9.2 kWh/kg energy consumption for n-hexadecane conversion, and 4.0 kWh/m3 energy consumption for gas generation, and the mass balance of the product was determined. • Plasma effectively integrates electrical energy into chemical energy. • Rapid and effective one-step cracking of n-hexadecane. • Pulsed discharge enables low-energy production of syngas, C 2 and gasoline. • Emission spectroscopy results can explain changes in gas yield and concentration. [ABSTRACT FROM AUTHOR]

Flux-modulated permanent-magnet synchronous machine (FM-PMSM) is characterized as a high-torque direct-drive electrical machine, but may suffer from the low power factor. This paper aims to investigate the issue of the low power factor in theory and explore the possibilities for improvement. An analytical model for the FM-PMSM is developed to obtain the magnetic field distribution, and its accuracy is verified by the finite-element method. On the basis of the developed analytical model, a fast approach is developed to predict the power factor of the FM-PMSM. The analytical results indicate that the low flux density in the inner air gap excited by the PMs is responsible for the low power factor. Finally, the influences of several key design parameters on the power factor are studied, and the FM-PMSM is optimized afterward. The results show that the power factor of the FM-PMSM could be improved by 20% in comparison with the initial design. [ABSTRACT FROM AUTHOR]

It is desirable to prepare low-cost non-noble metal catalysts using a simple and efficient method. Herein, we display for the first time that nitrogen-doped hierarchical porous carbon-supported vanadium nitride (VN/NC/C-x) catalysts can be regulated by dicyandiamide (DCDA). The introduction of DCDA not only effectively controls the pore structure, but also plays an important role in adjusting oxygen vacancies and d-electrons. In addition, DCDA is not only a significant raw material for the N-doped carbon, but also a nitrogen source for the preparation of vanadium nitride. The VN/NC/C-3 catalyst was prepared after optimization of the preparation parameters, and the macro/micro structure demonstrates a superior ORR performance in alkaline media with a positive onset potential of 0.85 V and a half-wave potential of 0.75 V, the limiting current density is as high as 4.52 mA·cm−2, and the Tafel slope is only 75.54 mV·dec−1. The VN/NC/C-3-based Zn–air battery exhibits a highest peak power density (161.82 mW∙cm−2) and an excellent energy density (702.28 mAh·kgZn−1 and 861.51 Wh·kgZn−1). This work provides a valuable synthetic approach for the preparation of other transition metal nitride catalysts with a relative economic value and high performance. [ABSTRACT FROM AUTHOR]

The methane dehydro-aromatization reaction (MDA) is a promising methane valorization process due to the conversion of methane to value-added aromatics (benzene, toluene and naphthalene). However, one of the major disadvantages of utilizing zeolite in MDA is that the catalyst is rapidly inactivated due to coke formation, which eventually causes the activity and aromatic selectivity to decrease. Consequently, the process is not conducive to large-scale industrial applications. The reasonable control of Mo site distribution on the zeolite surface is the key factor for partially inhibiting the coking of the catalyst and improving stability. Here, MoO3 nanobelts can be used for alternative Mo precursors to prepare MDA catalysts. Catalysts modified with MoO3 nanobelts present higher activity (13.4%) and benzene yield (9.2%) than those catalysts loaded with commercial MoO3. [ABSTRACT FROM AUTHOR]

To achieve ultra-strong joint performance and high processing efficiency of joining dissimilar metals, a novel hybrid process, Expanding-Welding method (EW), was proposed. EW effectively combined metallurgical bonding and mechanical expanding effects in a single process. To demonstrate its effectiveness, EW was applied to join aluminum tube to steel tube-sheet hybrid structure. Molecular dynamics analysis showed that the Al/Fe diffusion coefficient was increased by 2 orders of magnitude under the compression and shear condition. Severe plastic deformation introduced by the welding tool induced rapid atom diffusion behavior, and the thickness of the diffusion layer reached 9.5 ± 0.4 µm. The maximum joint pull-out strength was 176.5 ± 13.7 MPa, reaching 73.5% of that of base Al alloys. The success of this hybrid deformation-welding process can increase energy efficiency in many industrial sectors, such as constructing reliable tube-to-tube-sheet structures with dissimilar metals for heat exchangers in the field of petroleum and chemical industries. [Display omitted] • As a hybrid deformation and welding process, Expanding-Welding method was effective to join dissimilar metals. • Aluminum tube to steel tube-sheet structure was joined, which had application potential for heat exchangers. • Severe plastic deformation induced atom rapid diffusion at Al/Fe interface with compression and shear. • The pull-out strength 176.5 ± 13.7 MPa reached 73.5% of base Al alloys, showing excellent mechanical joint performance. [ABSTRACT FROM AUTHOR]

Recently, the non-covalently activated supramolecular scaffold method has become a prominent research area in the field of intelligent materials. Here, the inorganic clay (LP) promoted the AIE properties of 4,4′,4″,4‴-(ethene-1,1,2,2-tetrayltetrakis(benzene-4,1-diyl))tetrakis(1-ethylpyridin-1-ium) (P-TPE), showing an astonishing 42-fold enhancement of the emission intensity of the yellow-green luminescence and a 34-fold increase of the quantum yield via organic-inorganic supramolecular strategy as well as the efficient light-harvesting properties (energy transfer efficiency up to 33 %) after doping with the dye receptor Rhodamine B. Furthermore, the full-color spectral regulation, including white light, was achieved by adjusting the ratio of the donor to the acceptor component and co-assembling with the carbon dots (CD). Interestingly, this TPE-based non-covalently activated full-color supramolecular light-harvesting system (LHS) could be achieved not only in aqueous media but also in the hydrogel and the solid state. More importantly, this panchromatic tunable supramolecular LHS exhibited the multi-mode and quadruple digital logic encryption property as well as the specific detection ability towards the perfluorobutyric acid and the perfluorobutanesulfonic acid, which are harmful to human health in drinking water. This result develops a simple, convenient and effective approach for the intelligent anti-counterfeiting and the pollutant sensing. • Here, we developed a novel LP-activated LHS assembly for the anti-counterfeiting and detecting the perfluorinated pollutants.[Not Available in CrossRef]. [ABSTRACT FROM AUTHOR]

In this paper, we described a straightforward one-step chemical method for the synthesis of semiconductor quantum dots(QDs)—block copolymer brushes functionalized graphene oxide(GO) fluorescence nanohybrids. The azobenzene-terminated block copolymer poly(N-isopropylacrylamid)-b-poly(styrene-co-5-(2-methacryoylethyloxymethyl)-8-quinolinol)(PNIPAM-b-P(St-co-MQ)) was modified on the surface of GO sheets via host–guest interactions between β-cyclodextrin-modified GO and azobenzene moieties, and simultaneously CdSe/ZnS QDs were integrated on the block copolymer brushes through the coordination between 8-hydroxyquinoline units in the polymer brushes and CdSe/ZnS QDs. The resulting fluorescence nanohybrid exhibited dual photoluminescence at 620 nm and 526 nm, respectively, upon excitation at 380 nm and LCST-type thermo-responsive behavior which originated from the change in the PNIPAM conformation in the block copolymer brushes of GO sheets. [ABSTRACT FROM AUTHOR]

Background: Particular matter 2.5 (PM2.5) is one of the most important air pollutant, and it is positively associated with the development of chronic obstructive pulmonary disease (COPD). However, the precise underlying mechanisms through which PM2.5 promotes the development of COPD remains largely unknown.Methods: Mouse alveolar destruction were determined by histological analysis of lung tissues and lung function test. Alveolar type II cells (AT2) to alveolar type I cells (AT1) transition in PM2.5-induced COPD mouse model was confirmed via immunofluorescence staining and qPCR analysis. The differentially expressed genes in PM2.5-induced COPD mouse model were identified by RNA-sequencing of alveolar epithelial organoids and generated by bioinformatics analysis.Results: In this study, we found that 6 months exposure of PM2.5 induced a significantly decreased pulmonary compliance and resulted in pulmonary emphysema in mice. We showed that PM2.5 exposure significantly reduced the AT2 to AT1 cell transition in vitro and in vivo. In addition, we found a reduced expression of the intermediate AT2-AT1 cell process marker claudin 4 (CLDN4) at day 4 of differentiation in mouse alveolar organoids treated with PM2.5, suggesting that PM2.5 exposure inhibited AT2 cells from entering the transdifferentiation process. RNA-sequencing of mouse alveolar organoids showed that several key signaling pathways that involved in the AT2 to AT1 cell transition were significantly altered including the Wnt signaling, MAPK signaling and signaling pathways regulating pluripotency of stem cells following PM2.5 exposure.Conclusions: In summary, these data demonstrate a critical role of AT2 to AT1 cell transition in PM2.5-induced COPD mouse model and reveal the signaling pathways that potentially regulate AT2 to AT1 cell transition during this process. Our findings therefore advance the current knowledge of PM2.5-induced COPD and may lead to a novel therapeutic strategy to treat this disease. [ABSTRACT FROM AUTHOR]

Abstract: We study the dynamics of dissipative spatial solitons by using antisymmetric-type spatially inhomogeneous loss that locally modulates an optical medium described by the complex Ginzburg–Landau model. We reveal soliton dynamics by launching input solitons at different positions of the spatial modulation loss profile, including its zero value and positive value. The soliton transverse drift exhibits tilt straightaway propagation except for the oscillation in initial stage. The tilt angle of the soliton drift can be controlled by the modulation parameters. We also investigate the dependences of the tilt angle of the soliton drift on the amplitude of the inhomogeneous loss and the linear loss coefficient. [Copyright &y& Elsevier]

The triarylamine–based donor–π bridge–acceptor dyes (namely, Ds-3, Ds-5 and Ds-6), with the higher conversion efficiency of sunlight to electricity, have been studied with quantum chemistry methods. The geometrical structure, frontier molecular orbital and electronic vertical excitation energies were calculated by using the density functional theory (DFT) and the time-dependent DFT with the Cam-B3LYP and PBE0 functional. From the calculated results, we perform a three-dimensional real-space analysis, which demonstrates that the lowest energy excited state of the triarylamine-based dye is a charge transfer (CT) excited state and electrons shift from triarylamine to cyanoacrylic acid group. The excited-state oxidation potentials and driving force energy are identified as the essential parameters to study the electron injection ability of the excited dyes. The evaluation of photochemical parameter and the visualised study of CT process provide the important information for revealing the relationship between structure and photochemical property of the triarylamine-based dyes. [ABSTRACT FROM AUTHOR]

Abstract: Calcium phosphate ceramics are considered as the most promising materials for bone tissue engineering due to their excellent biocompatibility and bioactivity. In the paper, porous calcium phosphate scaffolds were prepared via selective laser sintering with various weight ratios of TCP/HAP (0/100, 10/90, 30/70, 50/50, 70/30 and 100/0) powders. Furthermore the effect of phase composition on biological and mechanical properties of the scaffold was investigated. The results showed that both the fracture toughness and compressive strength increased with increasing content of TCP from 0 to 30wt.%, and then dropped with a further increasing content of TCP. The scaffold made of TCP/HAP with a ratio of 30/70 exhibited the optimum fracture toughness (1.33MPam1/2) and compressive strength (18.35MPa). After the scaffolds were soaked in SBF for 7days, the apatite agglomerates formed on the surface of the scaffolds and the dissolution rate of the scaffolds increased with the increasing content of the TCP. In vitro cell culture indicated that a balance between biological stability and biodegradation rate was helpful for cell adherence and proliferation. It was concluded that the scaffold sintered with TCP/HAP(30/70) performed with optimum mechanical and biological properties. [Copyright &y& Elsevier]