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ZnO-based photocatalytic materials have received widespread attention due to their usefulness than other photocatalytic materials in organic dye wastewater treatment. However, its photocatalytic efficiency and surface stability limit further applicability. This paper uses a one-step carbonization method to prepare multifunctional ZnO/carbon hybrid nanofiber mats. The carbonization creates a π-conjugated carbonaceous structure of the mats, which prolongs the electron recovery time of ZnO nanoparticles to yield improved photocatalytic efficiency. Further, the carbonization reduces the fiber diameter of the carbon hybrid nanofiber mats, which quadruples the specific surface area to yield enhanced adsorption and photocatalytic performance. At the same time, the prepared nanofiber mats can increase the evaporation rate of water under solar irradiation to a level of 1.46 kg·m−2·h−1 with an efficiency of 91.9%. Thus, the nanofiber mats allow the facile incorporation of photocatalysts to clean contaminated water through adsorption, photodegradation, and interfacial heat-assisted distillation mechanisms.

The Kyushu-Palau Ridge (KPR), a remnant arc on the Philippine Sea Plate (PSP), is subducting beneath the Kyushu, southwest Japan. Influenced by the subducting KPR, the Kyushu subduction zone corresponding to the KPR is significantly different from Shikoku subduction zone in terms of gravity anomalies, seismicity, the stress state, and the subducting slab morphology. Significant negative free-air and Bouguer gravity anomalies are observed in a prolonged area of KPR, southeast of the Miyazaki Plain, indicating that this is where KPR overlaps the overriding plate. The gravity anomaly in this area is much lower than that in other areas where the inferred KPR extends, suggesting that the subduction of the buoyant KPR may cause the lower mantle density to decrease. More earthquakes have occurred in Hyuga-nada region where the KPR subducts than in Shikoku forearc and other areas in the Kyushu forearc, indicating that the subduction of the KPR enhances the local coupling between the subducting and overriding plates. The centroid moment tensor (CMT) mechanism of earthquakes shows that stress is concentrated in the accumulated crust beneath the Kyushu forearc corresponding to the KPR, and the shallow thrusting events in the obducting plate are caused by the KPR subduction. The buoyant KPR, with a large volume of low-density sediments, was responsible for the differences of the subduction depth and dip angle of the subducting Philippine Sea (PS) slab between northern Kyushu and Shikoku. The seismic gaps and the sudden change of the dipping angle of the subducting PS slab indicate that slab tear may have occurred along the west side of the KPR beneath southwest Kyushu. A two-tear model was proposed, and the subduction of the buoyant KPR was believed to play an important role in the slab tear.

Nanofiber membranes have attracted considerable interest in water filtration owing to their unique structure and excellent performance, but large pore size and wide pore size distribution combined with weak inter-fiber strength are major limitations for practical applications. This work describes a facile and efficient method for nanofiber membrane fabrication with stable mechanical properties, high separation and excellent antifouling performance. The nanofiber membranes are prepared from a mixture of a low melting point polymer (thermoplastic polyurethane, TPU, Tm = 52 °C) and a structural skeleton-forming polymer (polyacrylonitrile, PAN, Tm = 317 °C) that undergoes electrospinning and hot-pressing. Hot-pressing treatment at 50–80 °C and 2 MPa melts the TPU phase to create inter-fiber connections, thereby reducing the nanofiber membrane pore size and improving its dimensional stability and mechanical properties. The connectivity of the nanofiber membrane can be controlled by adjusting the ratio of TPU and PAN in the nanofiber and the hot-pressing temperature. The tensile strength and Young's modulus of the hot-pressed membrane are 24.5 MPa and 630.6 MPa, which are 4.8 times and 6.0 times higher than the nascent membrane, respectively. The membrane pressed at 80 °C shows excellent filtration performance, with a high pure water flux of 8490 L m−2 h−1 and active sludge and 100 nm SiO2 suspension retention efficiency of 99.99%. In addition, the hot-pressed membranes exhibited excellent antifouling performance and mechanical properties, meet the reusability and long-term service demand. Therefore, hot-pressed composite nanofiber membranes made of low melting point thermoplastic polymer and a skeleton polymer provide a facile and economical approach for the development of high-performance separation media.

Aerosol nanoparticle deposition onto a surface under a temperature gradient is commonly applied in the chemical and medical industries. In this study, a numerical investigation with a two-phase model is used to investigate the deposition characteristics of nanosized particles in a 90° square bend. The effects of variations in the gas phase physical parameters, such as density, viscosity, and thermal diffusivity with changing temperatures are studied. The main forces acting on the particles are the drag forces, Brownian forces, and thermophoretic forces. A discrete phase model (DPM) based on the FLUENT software is used to investigate particle transfer. The results show that in a temperature gradient flow, particles move towards the colder wall, and some of them strike and deposit onto its surface. The particle deposition efficiency increases with the temperature gradient rising. The Brownian force plays a more important role in particle deposition when smaller particles are used. Because of inertia and gravity, particle deposition on the four surfaces of a 90° square bend tube is inhomogeneous. The deposition efficiency on the floor surface increases with increasing particle diameter. On the contrary, larger particles decrease the deposition efficiency on the ceiling surface.

Zeolites have been widely used in the adsorption and removal of volatile organic compounds (VOCs). In this study, we investigated the adsorption properties of 9 commercial zeolites and MCM-41 mesoporous silica for p-xylene. And then zeolites with hierarchical structures were prepared by alkali (0.1–0.8 mol•L−1 mixed alkali solution) modification and their adsorption and desorption properties were investigated for various VOCs. The structure of these materials was thoroughly characterized, and the relationship between the adsorption capacity and physical parameters was investigated. It was found that the pore diameter and Si/Al ratio were the most important parameters for p-xylene adsorption under humid conditions, which should be optimized simultaneously to achieve satisfactory adsorption capacity. And the best adsorption capacity could reach approximately 100 mg•g−1 in humid conditions. Meanwhile, enhancing the diffusion of the VOC molecules in microporous zeolites with micron crystals through the manufacture of hierarchical structure was also important. The adsorption capacity of the modified zeolites increased by more than 25%, and the desorption temperature decreased. It showed that the alkali modification not only improved the utilization efficiency of the adsorption sites, but also facilitated desorption, which is crucial for adsorbing materials.

In this paper, a new proposed transformer winding fault detection method is adopted to test the common faults of the transformer, short circuit, and deformation. Taking the 10 kV three-phase double-winding transformer as the research object, the normal and faulty transformers are detected by the sweep impedance method. And the sweep impedance curve changes before and after the fault. The test results show that the difference of the sweep impedance curve of the transformer winding short circuit and the concave deformation fault is obvious. The fault can be judged by the sweep impedance spectrum. The feasibility and effectiveness of the sweep impedance method for transformer winding deformation detection are verified.

Flying Ad-Hoc Network (FANET) is a special type of Mobile Ad-Hoc Network (MANET) consisted of a swarm of Unmanned Aerial Vehicles(UAVs). Mission planning for effective cooperative UAV searching must take into account the connectivity of UAVs for information sharing among UAVs in the FANET. Traditional mission planning usually uses predefined routes or use simple mobility models to generate the trajectories of UAVs, which do not take network connectivity as an important factor for high-quality cooperative searching. On the other hand, many innovative FANET mobility models have been investigated only for FANET simulation. In this paper, we propose a framework applying a recent group mobility model to mission planning with consideration on the network connectivity. For this purpose, we extend the Spatiotemporally Correlated Group Mobility Model (STGM) with adaptivity on its parameters that decide the spatial or temporal correlations among UAVs. Next, we introduce an area information coverage metric to evaluate the quality of mission planning enhanced by this adaptive mobility model. Finally, an algorithm is designed to optimize the metric. The experimental results show that our framework gains impressive improvements on effective information collection by the UAV swarm.

Flying Ad-Hoc Network (FANET) is a special type of Mobile Ad-Hoc Network (MANET) which consists of multiple networked Unmanned Aerial Vehicles (UAVs). Compared to traditional target search using a single UAV, multiple cooperative UAVs within a FANET have the potential to accomplish this work more efficiently, and multi-UAV cooperative target search has attracted increasing research attention in recent years. In this paper, we conduct a comprehensive investigation on efficient multi-UAV cooperative search on moving targets. More specifically, we propose an adaptive Track-Explore adjustment strategy to dynamically assign the search task of each UAV at each time-step. Meanwhile, to improve the search performance, we introduce a novel on-line path planning method to guide the flying decision of each UAV. The proposed search framework is compared with random walk method and an ideal (not achievable) state in different scenarios, and the simulation results show that our FATES framework works efficiently on multiple moving targets search tasks with great adaptability and robustness.

The rolling bearing is widely used as the mechanical rotating parts, whose state directly determines the performance of the whole machine. Since there exist the problems of low accuracy in traditional single sensor detection and lack of stable diagnostic system, acceleration and acoustic emission can be combined to conduct the study on the fault diagnosis of rolling bearing. The wavelet technology should be used to reduce the noise of the signal obtained by two kind of sensors. Hilbert technique is used to demodulate the signal after noise reduction, and the frequency domain envelope will be got. The eigenvector is obtained by calculating the frequency energy of the fault signal. Then Multi-sensor information fusion system is established by BP neural network in which the suitable samples is selected to train until the error meets the requirement, and the diagnosis of rolling bearing fault is realized.

With the rapid development of VLSI technique and the continuous improvement of application requirement, problems such as power consumption and clock skew of integrated circuit have become more and more serious. Because of having several advantages such as low power, high performance and elimination of global clock, asynchronous circuit and its design methodology have been paid more attention in recent years. An asynchronous design and implementation flow based on Balsa and synchronous tools has been firstly proposed in this paper, and GTECH-based optimization scheme and Black-box-based optimization scheme are embedded to reduce area and power. And then design methodology mixed with asynchronous circuit and synchronous circuit is proposed to meet the low power requirement of RFID baseband processor. Finally, our proposed RFID is carried out with an 180nm CMOS technology. Experimental results show that the power of our proposed RFID is less than one third of those of its synchronous counterparts, and our proposed RFID baseband processor can be easily integrated into an UHF RFID chip.

There is a need for new antimalarials, ideally with novel mechanisms of action. Benzoxaboroles have been shown to be active against bacteria, fungi, and trypanosomes. Therefore, we investigated the antimalarial activity and mechanism of action of 3-aminomethyl benzoxaboroles against Plasmodium falciparum Two 3-aminomethyl compounds, AN6426 and AN8432, demonstrated good potency against cultured multidrug-resistant (W2 strain) P. falciparum (50% inhibitory concentration [IC50] of 310 nM and 490 nM, respectively) and efficacy against murine Plasmodium berghei infection when administered orally once daily for 4 days (90% effective dose [ED90], 7.4 and 16.2 mg/kg of body weight, respectively). To characterize mechanisms of action, we selected parasites with decreased drug sensitivity by culturing with stepwise increases in concentration of AN6426. Resistant clones were characterized by whole-genome sequencing. Three generations of resistant parasites had polymorphisms in the predicted editing domain of the gene encoding a P. falciparum leucyl-tRNA synthetase (LeuRS; PF3D7_0622800) and in another gene (PF3D7_1218100), which encodes a protein of unknown function. Solution of the structure of the P. falciparum LeuRS editing domain suggested key roles for mutated residues in LeuRS editing. Short incubations with AN6426 and AN8432, unlike artemisinin, caused dose-dependent inhibition of [(14)C]leucine incorporation by cultured wild-type, but not resistant, parasites. The growth of resistant, but not wild-type, parasites was impaired in the presence of the unnatural amino acid norvaline, consistent with a loss of LeuRS editing activity in resistant parasites. In summary, the benzoxaboroles AN6426 and AN8432 offer effective antimalarial activity and act, at least in part, against a novel target, the editing domain of P. falciparum LeuRS.

Effects of the single addition of nitrogen (N) and boron (B) and the combined addition of N and B on continuous cooling transformation (CCT) diagrams and properties of the three Mo–V–Ti micro-alloyed steels were investigated by means of a combined method of dilatometry and metallography. Microstructures observed in continuous cooled specimens were composed of pearlite (P), quasi-polygonal ferrite (QPF), granular bainite (GB), acicular ferrite (AF), lath-like bainite (LB) and martensite (M) depending on the cooling rates and transformation temperatures. Single addition of 12 ppm B effectively reduced the formation of QPF and broadened the cooling rate region for LB and M. Added N makes the action of B invalid and the QPF region was prominently broadened, and even though the cooling rate is higher than 50°C s−1, it cannot obtain full bainite.

A new idea of using a stiffer metallic compound Mg 2 Si to enhance the damping capacities of pure magnesium and its alloys is successfully attempted. The present paper focuses on the relation between damping capacities and the addition amount of Si. The results show that damping capacities increase with increasing amount of Si. Particular emphasis is placed on the increasing dislocation density around matrix–particulate interface and the refinement of grain size promoted by big growth restriction factor of Si.

The structural, electronic and elastic properties of B2 structure Hafnium compounds were investigated by means of first-principles calculations based on the density functional theory within generalized gradient approximation (GGA) and local density approximation (LDA) methods. Both GGA and LDA methods can make acceptable optimized lattice parameters in comparison with experimental parameters. Therefore, both GGA and LDA methods are used to predict the electronic and elastic properties of B2 HfX (X = Os, Ir and Pt) compounds. Initially, the calculated formation enthalpies have confirmed the order of thermodynamic stability as HfPt > HfIr > HfOs. Secondly, the electronic structures are analyzed to explain the bonding characters and stabilities in these compounds. Furthermore, the calculated elastic properties and elastic anisotropic behaviors are ordered and analyzed in these compounds. The calculated bulk moduli are in the reduced order of HfOs > HfIr > HfPt, which has exhibited the linear relationship with electron densities. Finally, the anisotropy of acoustic velocities, Debye temperatures and thermal conductivities are obtained and discussed.

Four diastereomeric NADH model compounds were synthesized by the reaction of a pinyl substituted Hantzsch ester with dimethylaluminum amide. The reduction of methyl benzoylformate with these models gave both enantiomers of methyl mandelate.

Several microphone arrays, such as planar four-element array, symmetric three-dimensional square array, planar five-element cross array are common single arrays, which to be used in passive acoustic location with a relatively high frequency. In different articles, an array may be placed in a different way, for example, turned the array at an angle along the z-axis (e.g.90ia). The relationship between the basic array and rotating array is one research on this paper. Some articles proposed to increase the number of sensors in the single array can improve detection accuracy, its essence is to increase the delay information that can reduce the location error of the array. Inspired by this, the other research is the impact of utilization of the delay information on the location accuracy of single array, which has a certain number of sensors.