High Performance Ultraviolet Photodetector Fabricated with ZnO Nanoparticles-graphene Hybrid Structures

Ultraviolet （UV） photodetector constructed by ZnO material has attracted intense research and commercial interest. However, its photoresistivity and photoresonse are still unsatisfied. Herein, we report a novel method to assemble ZnO nanoparticles （NPs） onto the reduced graphite oxide （RGO） sheet by simple hydrothermal process without any surfactant. It is found that the high-quality crystallized ZnO NPs with the average diameter of 5 nm are well dispersed on the RGO surface, and the density of ZnO NPs can be readily controlled by the concentration of the precursor. The photodetector fabricated with this ZnO NPs- RGO hybrid structure demonstrates an excellent photoresponse for the UV irradiation. The results make this hybrid especially suitable as a novel material for the design and fabrication of high performance UV photodector.

The Design of Water-reusing Network with a Hybrid Structure Through Mathematical Programming

A new design method for a water-reusing network, with a hybrid structure, to reduce the complexity of the network and to minimize freshwater consumption, is proposed. The unique feature of the methodology proposed .in this article is to control the complexity of the water network by regulation of the control number in a water-reusing system. It combines the advantages of a conventional water-reusing network and a water-reusing net work with internal water mains. To illustrate the proposed method, a single contaminant system and a multiple contaminant system serve as examples of the problems.

Shake table testing of a multi-tower connected hybrid structure

Many single-tower reinforced concrete core wall-steel frame （RCC-SF） buildings have been built in China, but there are no buildings of different-height multi-tower hybrid system. A multi-tower RCC-SF tall building was thus studied because of its structural complexity and irregularity. First, a 1/15 scaled model structure was designed and tested on the shake table under minor, moderate, and major earthquake levels. Then, the dynamic responses of the model structure were interpreted to those of the prototype structure according to the similitude theory. Experimental results demonstrate that, despite the complexity of the structure, the lateral deformation bends as the ＂bending type＂ and the RC core walls contribute more than the steel frames to resist seismic loads. The maximum inter-story drift of the complex building under minor earthquakes is slightly beyond the elastic limitation specified in the Chinese code, and meets code requirements under major earthquakes. From the test results some suggestions are provided that could contribute favorable effect on the seismic behavior and the displacement of the building.

Room temperature NO_2 gas sensing of Au-loaded tungsten oxide nanowires/porous silicon hybrid structure

In this work, we report an enhanced nitrogen dioxide（NO_2） gas sensor based on tungsten oxide（WO_3）nanowires/porous silicon（PS） decorated with gold（Au） nanoparticles. Au-loaded WO_3 nanowires with diameters of 10 nm–25 nm and lengths of 300 nm–500 nm are fabricated by the sputtering method on a porous silicon substrate. The high-resolution transmission electron microscopy（HRTEM） micrographs show that Au nanoparticles are uniformly distributed on the surfaces of WO_3 nanowires. The effect of the Au nanoparticles on the NO_2-sensing performance of WO_3 nanowires/porous silicon is investigated over a low concentration range of 0.2 ppm–5 ppm of NO_2 at room temperature（25℃）. It is found that the 10-？ Au-loaded WO_3 nanowires/porous silicon-based sensor possesses the highest gas response characteristic. The underlying mechanism of the enhanced sensing properties of the Au-loaded WO_3 nanowires/porous silicon is also discussed.

Sound Absorption Enhancement by Thin Multi-Slit Hybrid Structures

We report an extraordinary sound absorption enhancement in low and intermediate frequencies achieved by a thin multi-slit hybrid structure formed by incorporating micrometer scale micro-slits into a sub-millimeter scale meso-slit matrix. Theoretical and numerical results reveal that this exotic phenomenon is attributed to the noticeable velocity and temperature gradients induced at the junctures of the micro- and meso-slits, which cause significant loss of sound energy as a result of viscous and thermal effects. It is demonstrated that the proposed thin multi-slit hybrid structure with micro-scale configuration is capable of controling low frequency noise with large wavelength, which is attractive for applications where the size and weight of a sound absorber are restricted.

Synthesis and room-temperature NO_2 gas sensing properties of a WO_3 nanowires/porous silicon hybrid structure

We report on the fabrication and performance of a room-temperature NO2 gas sensor based on a WO3 nanowires/porous silicon hybrid structure. The W18O49 nanowires are synthesized directly from a sputtered tungsten film on a porous silicon （PS） layer under heating in an argon atmosphere. After a carefully controlled annealing treatment, WO3 nanowires are obtained on the PS layer without losing the morphology. The morphology, phase structure, and crystallinity of the nanowires are investigated by using field emission scanning electron microscopy （FESEM）, X-ray diffractometer （XRD）, and high-resolution transmission electron microscopy （HRTEM）. Comparative gas sensing results indicate that the sensor based on the WO3 nanowires exhibits a much higher sensitivity than that based on the PS and pure WO3 nanowires in detecting NO2 gas at room temperature. The mechanism of the WO3 nanowires/PS hybrid structure in the NO2 sensing is explained in detail.

Static and Dynamic Analyses of Long-Span Spatial Steel-Cable-Membrane Hybrid Structures

With the increment of the complexity of structural systems and the span of spatial structures, the interactions between parts of the structures, especially between some flexible substructures, become too complex to be analyzed clearly. In this paper, taking an actual gymnasium of a long-span spatial steel-cable-membrane hybrid structure as the calculation model, the static and dynamic analyses of the hybrid structures are performed by employing the global analysis of the whole hybrid structure and the substructural analysis of the truss arch substructure, the cable-membrane substructure, etc. In addition, the comparison of stresses and displacements of structural members in the global and substructural analyses is made. The numerical results show that serious errors exist in the substructural analysis of the hybrid structure, and the global analysis is necessary for the hybrid structure under the excitation of static loads and seismic loads.

Giant magnetoresistance in Fe/SiO_2/p-Si hybrid structure under non-equilibrium conditions

The giant magnetoresistive（MR） effect was investigated in a simple Fe/Si O2/p-Si-hybrid-structure-based device from two back-to-back Schottky diodes. The effect was revealed only under the non-equilibrium conditions caused by optical radiation. It is demonstrated that the magnetoresistance ratio attains 100 or more. The main peculiarity of the MR behavior is its strong dependence on the magnitude and the sign of the bias current across the device and, most surprisingly, upon polarity of the magnetic field. It is important that the magnetoresistive effect is implemented exclusively in the subsystem of minority charge carriers transferred to the non-equilibrium states. The development of magneto-sensitive devices of this type can give grounds for a novel direction of semiconductor spintronics.

Flexible piezoelectric nanogenerators based on a fiber/ZnO nanowires/paper hybrid structure for energy harvesting

We present a novel, low-cost approach to fabricate flexible piezoelectric nano- generators （NGs） consisting of ZnO nanowires （NWs） on carbon fibers and foldable Au-coated ZnO NWs on paper. By using such designed structure of the NGs, the radial ZnO NWs on a cylindrical fiber can be utilized fully and the electrical output of the NG is improved. The electrical output behavior of the NGs can be optionally controlled by increasing the fiber number, adjusting the strain rate and connection modes. For the single-fiber based NGs, the output voltage is 17 mV and the current density is about 0.09 μA·cm^-2, and the electrical output is enhanced greatly compared to that of previous similar micro-fiber based NGs. Compared with the single-fiber based NGs, the output current of the multi-fiber based NGs made of 200 carbon fibers increased 100-fold. An output voltage of 18 mV and current of 35 nA are generated from the multi-fiber based NGs. The electrical energy generated by the NGs is enough to power a practical device. The developed novel NGs can be used for smart textile structures, wearable and self-powered nanodevices.

Multi-scale design and optimization for solid-lattice hybrid structures and their application to aerospace vehicle components

By integrating topology optimization and lattice-based optimization,a novel multi-scale design method is proposed to create solid-lattice hybrid structures and thus to improve the mechanical performance as well as reduce the structural weight.To achieve this purpose,a two-step procedure is developed to design and optimize the innovative structures.Initially,the classical topology optimization is utilized to find the optimal material layout and primary load carrying paths.Afterwards,the solid-lattice hybrid structures are reconstructed using the finite element mesh based modeling method.And lattice-based optimization is performed to obtain the optimal crosssection area of the lattice structures.Finally,two typical aerospace structures are optimized to demonstrate the effectiveness of the proposed optimization framework.The numerical results are quite encouraging since the solid-lattice hybrid structures obtained by the presented approach show remarkably improved performance when compared with traditional designs.

Quantum transport in topological insulator hybrid structures-A combination of topological insulator and superconductor

In this paper,a brief review of the history of topological insulators is given.After that,electronic transport experiments in topological insulator-superconductor hybrid structures,including experimental methods,physical properties and seemingly contradictory observations are discussed.Additionally,some new topological insulator hybrid structures are proposed.

Phosphorus-doped NiS_(2)electrocatalyst with a hybrid structure for hydrogen evolution

In this article,P-NiS_(2)/Ni_(x)P electrocatalysts were synthesized by dealloying the Ni-Al precursor followed by phosphosulfide treatment.We found that the hybrid structure of P-NiS_(2)/Ni_(x)P provides rich active sites for the surface hydrogen evolution reaction (HER),and the doping of P enhances the electronic conductivity of electrodes.In particular,the obtained electrode shows a low overpotential of 196 mV at 10 mA cm^(-2)and a small Tafel slope of only 110 mV dec^(-1)in the HER.Meanwhile,longterm constant current electrolysis test experiments indicate that P-NiS_(2)/Ni_(x)P has good service stability.This research will help to open a new window on the design and fabrication of HER electrocatalysts.

Numerical Investigation on Pool Boiling Mechanism of Hybrid Structures with Metal Foam and Square Column by LBM

In the present study, pool boiling heat transfer performance and bubble behaviors of hybrid structures with metal foam and square column are investigated by lattice Boltzmann method. By using the vapor-liquid phase change model of Gong-Cheng and Peng-Robinson equation of state, the effects of structural parameters, including metal foam thickness, porosity, column height and ratio of column width(W) to gap spacing(D) are investigated in details. The results show that hybrid structure performs better than pure columnar structure in pool boiling heat transfer. The hybrid structure accelerates bubble growth by fluid disturbance while metal skeletons prevent the bubble escaping. The optimum ratio of column width to gap spacing decreases with the increase of heat flux and HTC(heat transfer coefficient) can achieve an increase up to 25% when W/D change from 5/3 to 1/3. The increase of column height enhances heat transfer by expanding surface area and providing space for bubble motion. The metal foam thickness and porosity have a little influence on pool boiling heat transfer performance, but they have an important effect on bubble motion in the regime.

Experiment on Seismic Performance of Frame-Masonry Horizontal Hybrid Structure Based on Shaking Table Test

Frame-masonry horizontal hybrid structure is a new type of self-built residence in the rural areas of Fujian Province in recent years. A shaking table test for 1/2 scale model is carried out on the basis of one representative rural structure, and the dynamic characteristics and seismic responses of this experimental model are measured. As a supplement, the finite element model of the prototype structure is built by ANSYS software,and simulation and test results are contrasted and analyzed. The results show that according to this structure,the beam-column joint of the frame part has stress concentration and the destruction pattern of the masonry part is similar to brick-masonry structure. There are obvious differences in lateral stiffness of each floor and direction,and the mass center does not coincide with the stiffness center, which can lead to excessive torsion and story drift of this structure under earthquakes of a certain intensity. Because of poor construction quality, unfavorable structural measures and irrational structural system in present rural areas, there is a potential safety threat with this type of structures in highly seismic region. Some suggestions for strengthening and retrofitting frame-masonry horizontal hybrid structures are pointed out.

Magic hybrid structure as multifunctional electrocatalyst surpassing benchmark Pt/C enables practical hydrazine fuel cell integrated with energy-saving H_(2)production

A hybrid catalyst structure can provide abundant active sites and tailored electronic properties,but the major challenge lies in achieving delicate control over its composition and architecture to improve the catalytic activity toward different electrochemical reactions simultaneously.Herein,we present the rational design of a magic hybrid structure with low Pt loading(5.90 wt%),composed of CoPt_(3)and CoPt nanoparticles supported on N-doped carbon(CoPt_(3)/CoPt⊂PLNC).Importantly,it shows superior multifunctional catalytic activity in alkaline conditions,requiring a low overpotential of 341 and 20 mV to achieve 10 mA cm^(−2)for the hydrazine oxidation reaction(HzOR)/hydrogen evolution reaction(HER),respectively,and it delivers a half-wave potential of 0.847 V for the oxygen reduction reaction(ORR).Theoretical calculations reveal that the metal-carbon hybrid modulates kinetic behavior and induces electron redistribution,achieving the energetic requirements for multiple electrocatalysis.We demonstrate sustainable H_(2)production utilizing solely the CoPt_(3)/CoPt⊂PLNC catalyst,without external electric power input,suggesting its inspiring practical utility.

A Into-Plane Rotating Micromirror Actuated by a Hybrid Electrostatic Driving Structure

A novel into-plane rotating rnicromirror actuated by a hybrid electrostatic driving structure is presented. The hybrid driving structure is made up of a planar plate drive and a vertical comb drive. The device is fabricated in SOI substrate by using a bulk-and-surface mixed silicon micromachining process. As demonstrated by experiment, the novel driving structure can actuate the mirror to achieve large-range continuous rotation as well as spontaneous 90°rotation induced by the pull-in effect. The continuous rotating range of the micromirror is increased to about 46° at an increased yielding voltage. The measured yielding voltages of the mirrors with torsional springs of 1 and 0.5μm in thickness are 390 - 410V and 140 - 160V, respectively. The optical insertion loss has also been measured to be --1.98dB when the mirror serves as an optical switch.

Efficient removal of U(VI) from wastewater by a sponge-like 3D porous architecture with hybrid electrospun nanofibers

Removal of uranium(VI)from nuclear wastewater is urgent due to the global nuclear energy exploitation.This study synthesized novel sponge-like 3D porous materials for enhanced uranium adsorption by combining electrospinning and fibrous freeze-shaping techniques.The materials possessed an organic-inorganic hybrid architecture based on the electrospun fibers of polyacrylonitrile(PAN)and SiO_(2).As a sup-porting material,the surface of fibrous SiO_(2) could be further functionalized by cyano groups via(3-cyanopropyl)triethoxysilane.All the cyano groups were turned into amidoxime(AO)groups to obtain a amidoxime-functionalized sponge(PAO/SiO_(2)-AO)through the subsequent ami-doximation process.The proposed sponge exhibited enhanced uranium adsorption performance with a high removal capacity of 367.12 mg/g,a large adsorption coefficient of 4.0×10^(4)mL/g,and a high removal efficiency of 97.59%.The UO_(2)^(2+)adsorption kinetics perfectly conformed to the pseudo-second-order reaction.The sorbent also exhibited an excellent selectivity for UO_(2)^(2+) with other interfering metal ions.2023 Hohai University.Production and hosting by Elsevier B.V.

Estimation Method of State-of-Charge For Lithium-ion Battery Used in Hybrid Electric Vehicles Based on Variable Structure Extended Kalman Filter

Since the main power source of hybrid electric vehicle（HEV） is supplied by the power battery,the predicted performance of power battery,especially the state-of-charge（SOC） estimation has attracted great attention in the area of HEV.However,the value of SOC estimation could not be greatly precise so that the running performance of HEV is greatly affected.A variable structure extended kalman filter（VSEKF）-based estimation method,which could be used to analyze the SOC of lithium-ion battery in the fixed driving condition,is presented.First,the general lower-order battery equivalent circuit model（GLM）,which includes column accumulation model,open circuit voltage model and the SOC output model,is established,and the off-line and online model parameters are calculated with hybrid pulse power characteristics（HPPC） test data.Next,a VSEKF estimation method of SOC,which integrates the ampere-hour（Ah） integration method and the extended Kalman filter（EKF） method,is executed with different adaptive weighting coefficients,which are determined according to the different values of open-circuit voltage obtained in the corresponding charging or discharging processes.According to the experimental analysis,the faster convergence speed and more accurate simulating results could be obtained using the VSEKF method in the running performance of HEV.The error rate of SOC estimation with the VSEKF method is focused in the range of 5% to 10% comparing with the range of 20% to 30% using the EKF method and the Ah integration method.In Summary,the accuracy of the SOC estimation in the lithium-ion battery cell and the pack of lithium-ion battery system,which is obtained utilizing the VSEKF method has been significantly improved comparing with the Ah integration method and the EKF method.The VSEKF method utilizing in the SOC estimation in the lithium-ion pack of HEV can be widely used in practical driving conditions.

Au Microdisk-Size Dependence of Quantum Dot Emission from the Hybrid Metal-Distributed Bragg Reflector Structures Employed for Single Photon Sources

We investigate metallic microdisk-size dependence of quantum dot （QD） spontaneous emission rate and micro- antenna directional emission effect for the hybrid metM-distributed Bragg reflector structures based on a particular single QD emission. It is found that the measured photolumineseence （PL） intensity is very sensitive to the size of metMlic disk, showing an enhancement factor of 11 when the optimal disk diameter is 2μm and the numerical aperture of microscope objective NA=0.5. It is found that for large metal disks, the Purcell effect is dominant for enhanced PL intensity, whereas for small size disks the main contribution comes from plasmon scattering at the disk edge within the light cone collected by the microscope objective.

Symbiosis between fungi and the hybrid Cymbidium and its mycorrhizal microstructures

Tissue culture seedlings of the hybrid Cymbidium were inoculated with six different fungal strains, isolated from the roots of different wild terrestrial orchids. About three months later, the average increment of fresh weight of seedlings inoculated with strains CF1, CF3 and CF12 were respectively 130.26%, 345.65% and 153.34% while that of the control was only 88.40%. The differences between the three treatments and the control were statistically significant （α = 0.05）, highlighting the treatment with strain CF3 （α = 0.01）. In addition, the three strains were obtained by re-isolating. Pelotons, regarded as typical structures of orchid mycorrhiza, were also found in the inoculating roots under a microscope. It seems that the strains of CF1, CF3, and CF12 are associated with the hybrid Cymbidium and supplied the orchid with nutrition. It can be confirmed that the three strains are beneficial for the seedlings of this hybrid.