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One-dimensional (1D) topological insulators are superior for low-dissipation applications owing to the 1D character of surface states where scatterings other than prohibited backscattering are further restricted. Among the proposed candidates for 1D topological materials, TaNiTe5 has attracted intensive attention for its quasi-one-dimensional (quasi-1D) crystalline structure. In this study, we identify the chain-like construction and anisotropic electronic states on TaNiTe5 surface with scanning tunneling microscopy. The electron scatterings are largely suppressed even with chromium impurities deposited on the surface and magnetic field applied normal to the surface, which endows TaNiTe5 great potential for low-dissipation spintronic applications.

A straightforward solvothermal technique was used to create tin monosulfide (SnS) nanosheets that were reduced graphene oxide (RGO) bonded. On the folded RGO surface, it was discovered that the 2D SnS nanosheets had several layers that were evenly distributed. When exposed to visible light, a flexible photodetector made of PET substrate exhibits a 1.4 mA W−1 optical response, 3.5 × 107 Jones detection rate, and quick rise and fall times. (τ rise = τ decay = 0.08 s). When exposed to visible light, the methylene blue’s (MB) photocatalytic breakdown was used to test the photocatalytic performance of the synthesized SnS-RGO hybrid nanosheets. The fact that almost all of the MB dissolved in under one hour suggested that SnS-RGO nanosheets make promising high-performance photocatalysts.

The double-peaked distribution of particle deposition at divertor targets has been observed in various tokamaks, and is considered a potential approach for mitigating divertor particles and heat load in future fusion reactors. Recently, the systematical analysis of the double-peaked distribution behavior during EAST experiments shows that the appearance of the double-peaked profile is related to the line-average density and heating power. In order to understand general trends and related mechanisms, the influences of the upstream density (n e,sep) and power in the scrape-off layer (P SOL) on the double-peaked density profile are investigated by SOLPS-ITER simulations with full drifts and currents. It is found that the n e peak near the strike point is mainly contributed by the strong ionization source close to the target, and the n e peak in the far-SOL region is caused by the synergetic effects of poloidal and radial E × B drifts along the SOL. The double-peaked distribution is affected by the P SOL and impurity seeding by increasing or decreasing the whole profile of the electron temperature at the target (T et). When the peak value of T et (T et,peak) is fixed, the density peak in the far-SOL is increased for higher n e,sep by reducing the T et in the far-SOL region on the lower-field side under unfavorable B T and by the upstream-extended ionization source due to the geometry effect on the high-field side under favorable B T. Statistical analysis of the simulated results shows that the scaling expression of the peak ratio is ∼ T e t , p e a k − ( 1.4 ∼ 2.1 ) n e , s e p 1.6 ∼ 1.8 . In addition to the upper boundary found in the analysis of EAST experiments, a lower boundary of the region where the double-peaked feature appears on the P SOL-n e,sep plane is identified by simulations and preliminarily confirmed according to the measurements in several EAST discharges.

In this work, we investigate the epitaxial growth of InAs quantum dots (QDs) on Ge substrates. By varying the growth parameters of growth temperature, deposition thickness and the growth rate of InAs, high density (1.2 × 1011 cm−2) self-assembled InAs QDs were successfully epitaxially grown on Ge substrates by solid-source molecular beam epitaxy and capped by Ge layers. Pyramid- and polyhedral-shaped InAs QDs embedded in Ge matrices were revealed, which are distinct from the lens- or truncated pyramid-shaped dots in InAs/GaAs or InAs/Si systems. Moreover, with a 200 nm Ge capping layer, one-third of the embedded QDs are found with elliptical and hexagonal nanovoids with sizes of 7–9 nm, which, to the best of our knowledge, is observed for the first time for InAs QDs embedded in a Ge matrix. These results provide a new possibility of integrating InAs QD devices on group-IV platforms for Si photonics.

The performance of seismic exploration instruments directly affects the quality of acquired seismic data as well as the efficiency of seismic survey operation. Consequently, they play a pivotal role in oil/gas and mineral resource exploration. Compared with traditional cabled seismic acquisition systems, nodal seismic acquisition systems have the advantages of light weight, small size, low capital and operational cost, reduced health safety and environment risk and strong adaptability to complex terrain environment. Therefore, they have been widely used in seismic exploration and have shown a trend of accelerated development. The major manufacturers have carried out research and development of nodal instruments, and various types of nodal seismographs have appeared. Based on the investigation of influential nodal seismographs, we summarize the research status of nodal seismographs. Based on different wireless monitoring capabilities and data harvesting modes, we classify the nodal seismographs into a shoot-blind system, semi-blind system, real-time system and enhanced real-time system. We discuss structural principles and key technologies of the four types of nodal seismographs, analyze their characteristics and predict their future development directions. Focusing on node data quality monitoring, we discuss the application of communication technologies, such as Bluetooth, Wi-Fi, ZigBee, Long Term Evolution, and satellites in nodal seismographs in detail. Furthermore, we analyze and evaluate three main networking architectures including planar multi-hop networks, hierarchical cluster networks and hybrid networks, and sum up the research progress of wireless routing algorithms and large-scale seismic data real-time harvesting methods. Finally, the latest applications of nodal seismographs in energy and mineral resource exploration, geological environment monitoring, urban subsurface space survey and novel seismic technologies are covered. As research on the application of micro-electro-mechanical systems technology, cloud computing, 5G, Internet of Things, edge computing, machine learning and robotics in nodal systems deepens, the performance of nodal seismographs will be greatly promoted.

Detachment in helium (He) discharges has been achieved in the EAST superconducting tokamak equipped with an ITER-like tungsten divertor. This paper presents the experimental observations of divertor detachment achieved by increasing the plasma density in He discharges. During density ramp-up, the particle flux shows a clear rollover, while the electron temperature around the outer strike point is decreasing simultaneously. The divertor detachment also exhibits a significant difference from that observed in comparable deuterium (D) discharges. The density threshold of detachment in the He plasma is higher than that in the D plasma for the same heating power, and increases with the heating power. Moreover, detachment assisted with neon (Ne) seeding was also performed in L- and H-mode plasmas, pointing to the direction for reducing the density threshold of detachment in He operation. However, excessive Ne seeding causes confinement degradation during the divertor detachment phase. The precise feedback control of impurity seeding will be performed in EAST to improve the compatibility of core plasma performance with divertor detachment for future high heating power operations.

In this paper, the influence of a lightly doped p-GaN (p−-GaN) cap layer on p-GaN/AlGaN/GaN high electron mobility transistors (HEMTs) (LDP-HEMTs) was investigated. No difference in output or off-state breakdown characteristics was observed, but there was a negative shift in threshold voltage (V TH). The gate leakage (V GS = 7 V) dropped by three orders of magnitude, and the gate forward breakdown voltage and continuous operating voltage increased by 6.5 V and 2.5 V, respectively. It is worth noting that the gate characteristics are significantly optimized, which is ascribed to the employment of the p−-GaN cap layer. The simulations illustrate that the electric field is dispersed, and the electric peak is alleviated by the p−-GaN cap layer, thus suppressing the impact ionization and carrier injection in the high electric field. Furthermore, there is a negligible effect on the temperature reliability of V TH based on the temperature-dependent characteristics in LDP-HEMTs. However, the temperature stability of the gate current (V GS = 7 V) will worsen in LDP-HEMTs due to the difference in the conduction mechanism, compared with conventional p-GaN HEMTs.

The present work compares non-planar rotors designed using the blade element momentum (BEM) method and a vortex cylinder model. In a previous work, it is shown that blade element theory coupled with the superposition of the vortex cylinder model (BEVC) is able to model the loads of non-planar rotors. The result predicted by the BEVC model is in significantly improved agreement with higher-fidelity models than the loads as predicted using the BEM method. In this work, the BEM method and the BEVC method are integrated into a gradient-based optimization framework for aerodynamic planform optimization, in which the analytical gradients are obtained using the algorithmic differentiation (AD) method. In the present study, the rotor is assumed to be stiff for all cases such that the pure aerodynamic effects are highlighted. Loads of the optimized non-planar rotors with different geometries under different constraints designed from both methods are calculated using the BEM method, the BEVC method and also the higher-fidelity lifting-line (LL) method. Within the constraints of the present work it was found that the advantage of the BEVC method is not significant when comparing the integrated aerodynamic loads: the non-planar rotor designed using the BEM method gives similar total thrust and power as the rotor designed using the BEVC method when the designs are evaluated with the higher-fidelity LL method. However, the results confirmed that the distributed aerodynamic loads of the non-planar rotors predicted by the BEVC method are in improved agreement with the LL method compared to the BEM method.

Doubly peaked density distribution is expected not only to affect the plasma-wetted area at divertor plates, but also to correlate with the upstream density profile and hence characteristics of magnetohydrodynamic activities in tokamak plasmas (Wang et al 2020 Phys. Rev. Lett. 124 195002). Clarifying its origin is important to understand the compatibility between power/particle exhausts in divertor and high-performance core plasmas required by present-day and future tokamak devices. In this paper, we analyze the double-peak density profile appearing in the modeling during the physics design phase of the new lower tungsten divertor for EAST by using a comprehensive 2D SOLPS-ITER code package, including full drifts and currents, with a concentration on an unfavorable magnetic field (ion B × ∇B drift is directed away from the primary X-point). The results indicate that E × B drift induced by the plasma potential gradient near the target, which is closely related to the divertor state, plays essential roles in the formation of a double-peak profile at the target: (1) large enough radial E p × B drift produces a broadened high-density region; (2) strong poloidal E r × B drift drives a significant particle sink and creates a valley on the high-density profile. Thus, the simulation results can explain why this kind of doubly peaked density profile is usually observed at the high-recycling divertor regime. In addition, features of the double-peak ion saturation current distribution measured in preliminary experiments testing the new lower tungsten divertor are qualitatively consistent with the simulations.

Introducing metal thin films on two-dimensional (2D) material may present a system to possess exotic properties due to reduced dimensionality and interfacial effects. We deposit Pb islands on single-crystalline graphene on a Ge(110) substrate and studied the nano- and atomic-scale structures and low-energy electronic excitations with scanning tunneling microscopy/spectroscopy (STM/STS). Robust quantum well states (QWSs) are observed in Pb(111) islands and their oscillation with film thickness reveals the isolation of free electrons in Pb from the graphene substrate. The spectroscopic characteristics of QWSs are consistent with the band structure of a free-standing Pb(111) film. The weak interface coupling is further evidenced by the absence of superconductivity in graphene in close proximity to the superconducting Pb islands. Accordingly, the Pb(111) islands on graphene/Ge(110) are free-standing in nature, showing very weak electronic coupling to the substrate.

Based on the Extended SPC rules and real-time data fusion, the operating fault diagnosis model and application research of water injection wells were carried out. The historical operating parameters of water injection wells were studied, a multi-parameter rule fault chart was established, and the weight factors of fault diagnosis parameters were obtained based on expert Pcores. A operating fault diagnosis model of water injection wells based on SPC rules and real-time data fusion was constructed. The example analysis shows that the model has good adaptability in Bohai oilfield, can diagnose the fault of water injection wells in real time, quantitatively and accurately, and improves the intelligent level of real-time fault diagnosis of water injection wells.

The shortage of water resources has severely restricted the rapid development of modern cities in China, and the recycling of reclaimed water is one of the important methods to effectively solve the bottleneck problem of urban water shortages. Based on the Analytic Hierarchy Process (AHP), this study determines the evaluation indexes and their weights from social and technical levels respectively and constructs an evaluation index system of reclaimed water development and utilization potential, which contains 3 levels, 5 criteria and 19 alternatives, focusing on the production, utilization and benefit of reclaimed water and other characteristic indexes. From the weighting results of the index system, among the main influencing factors of reclaimed water development and utilization, the water quantity factor has the greatest influence, the influence of water usage and water quality assurance ranks second, and the economic factor has the least influence. This evaluation system provides a useful reference for the reasonable development and utilization of regional reclaimed water in the future.

Financial inclusion is a key policy for achieving the UN Sustainable Development Goals worldwide. However, emerging evidence has challenged the universal effectiveness of this policy. Combining a cross-sectional socio-economic and ecological survey with regional macro-economic and climatic data, we undertook an integrated causal analysis of the impact of financial inclusion policy on the Inner Mongolian herder social-ecological system. Exposure to economic globalization and climate change threatened herder livelihoods via increased feed costs and reduced livestock sales prices. Financial inclusion loans were beneficial for herders with large grassland plot size who used their traditional ecological knowledge to adapt via seasonal herd mobility. However, most herders were sedentary, constrained by small plot size, and used financial inclusion loans to reserve livestock and maintain high stocking densities. This strategy exposed them to inflated feed costs, increased their debt, and led to widespread grassland degradation. The results illustrate the limitations of financial inclusion policy in achieving sustainable development when people are trapped in poverty, subject to novel social-ecological contexts, and their ability to adapt is compromised. Transformative adaptations based on community cooperation, traditional knowledge and institutions, complementary public policies, and technological innovation are crucial to support financial inclusion policy and enhance sustainable development.

PbZr0.2Ti0.8O3 (PZT) gate insulator with the thickness of 30 nm is grown by pulsed laser deposition (PLD) in AlGaN/GaN metal–insulator–semiconductor high electron mobility transistors (MIS-HEMTs). The ferroelectric effect of PZT AlGaN/GaN MIS-HEMT is demonstrated. The polarization charge in PZT varies with different gate voltages. The equivalent polarization charge model (EPCM) is proposed for calculating the polarization charge and the concentration of two-dimensional electron gas (2DEG). The threshold voltage (V th) and output current density (I DS) can also be obtained by the EPCM. The theoretical values are in good agreement with the experimental results and the model can provide a guide for the design of the PZT MIS-HEMT. The polarization charges of PZT can be modulated by different gate-voltage stresses and the V th has a regulation range of 4.0 V. The polarization charge changes after the stress of gate voltage for several seconds. When the gate voltage is stable or changes at high frequency, the output characteristics and the current collapse of the device remain stable.

Blurred boundaries and heterogeneous intensities make accurate prostate MR image segmentation problematic. To improve prostate MR image segmentation we suggest an approach that includes: (a) an image patch division method to partition the prostate into homogeneous segments for feature extraction; (b) an image feature formulation and classification method, using the relevance vector machine, to provide probabilistic prior knowledge for graph energy construction; (c) a graph energy formulation scheme with Bayesian priors and Dirichlet graph energy and (d) a non-iterative graph energy minimization scheme, based on matrix differentiation, to perform the probabilistic pixel membership optimization. The segmentation output was obtained by assigning pixels with foreground and background labels based on derived membership probabilities. We evaluated our approach on the PROMISE-12 dataset with 50 prostate MR image volumes. Our approach achieved a mean dice similarity coefficient (DSC) of 0.90 ± 0.02, which surpassed the five best prior-based methods in the PROMISE-12 segmentation challenge. ARC

In this paper, through the analysis of the characteristics of camellia oleifera fruit (COF), a sheller with low damage rate of tea seeds, easy to manufacture and integrating shelling and screening functions is designed based on environment based design (EBD) method. The main structure of the COF sheller is designed and calculated. This design can provide a reference for the research of related machinery in camellia oleifera industry.

Based on the superlubricity theory, a new type of cutting fluid with excellent anti-friction and anti-wear effects is developed. Using the existing superlubricity agent, several new environmentally friendly water-based cutting fluids have been formulated; Further, the high-speed cutting tests of a new type of cutting fluid were carried out for titanium alloy. Finally, a large number of comparative analyses were performed based on the test results. Studies have shown that the friction coefficient obtained using the cutting fluid with solid lubricant is generally large, however, the lower friction coefficient can be obtained when using the cutting fluid with glycerol-acid and hexadecyl dimethyl ammonium bromide, also the better cooling and lubricating effects were obtained.

Weak layer is an important factor leading to slope instability, which cannot be ignored in slope stability analysis. In order to explore the influence of weak layers on the slope slip mode and stability of the slope, this paper selects typical open-pit mine slopes containing weak layers as the engineering background, and comprehensively uses geological survey, laboratory tests, theoretical analysis and other methods to verify the characteristics of slope geological structure and physical mechanical properties of soil, at the same time, uses simplified Bishop method to analyze the change law of slope stability under the change of weak layer dip angle, and finally clarifies the influence of weak layer on slope slip mode and stability. The results show that: the initial dip angle of the weak layer is 6°, the corresponding stability factor is 1.553 and the initial landslide mode is the combined failure of shear arc and weak layer. As the dip angle of the weak layer increases, the slope stability coefficient decreases. When the dip angle of the weak layer increases to 56°, the slope slip mode is transformed into the translational failure formed by the weak layer, and the stability factor is reduced to 1.055 at this time.

Rainfall is an important factor leading to slope landslide. Aiming at the problem of slope stability under rainfall, this paper uses the unsaturated seepage theory to dynamically describe the rainfall infiltration effect, and analyzes the distribution characteristics of pore water pressure of slope soil and the change law of slope water level under the action of rainfall, at the same time, deeply analyzes the law of slope stability changes based on strength reduction algorithm. The results show that: with the passage of rainfall time and the increase of rainfall intensity, the slope infiltration depth gradually increased. At the same time, rainfall increased the groundwater level in the slope, and leaded to increased pore water pressure in the slope soil, and the transient saturation zone gradually formed and expanded, and finally leaded to a significant reduction in slope stability coefficient.

Passive load alleviation on wind turbine blades can be achieved through geometric bend-twist coupling, for example by sweeping the blade backwards. In order to obtain the correct load distribution of a curved blade with in-plane sweep and/or out-of-plane dihedral, the influence of the blade shape on the aerodynamics must be modelled correctly. This includes the influence of the curved bound vortex, and it is especially important when designing a wind turbine blade with aeroelastic tailoring. In this paper, the background for modelling the curved bound vortex influence will be described in detail and a modified method is proposed. The proposed method of bound vorticity modelling is compared for curved and straight translating wings as well as wind turbine blades with results from a panel code and a Navier-Stokes solver. From this comparison, the advantages of the current modification with respect to the other lifting-line implementations are shown. The method proposed in the present work is general and applicable to any lifting-line like model.

One of the critical challenges for long pulse operation of ITER and future fusion reactors is the excessively high heat and particle fluxes on the divertor targets. The divertor detachment offers an effective way for the control of steady state heat flux and erosion at the divertor target. Dedicated experiments have been systematically performed for both H-mode and L-mode plasmas on EAST with ITER-like W divertor in the last two years to further advance detachment physics understanding. The detachment is identified by the rollover of divertor peak particle flux near the strike point during the density ramping up, which correlates with the reduction of electron temperature down to 5 eV, the increase of Dδ/Dα ratio and radiated power. It has been demonstrated that the more closed divertor has a lower density threshold at the onset of detachment on EAST. Furthermore, the detachment density threshold will be reduced when the strike point moves towards the divertor corner. The onset of detachment exhibits a strong asymmetry between inner and outer targets, with the inner target accessing detachment at lower density due to the lower electron temperature, as expected. The effects of the heating power and plasma current on the detachment onset were also investigated. The experimental results show that the density at detachment onset is lower in L-mode relative to H-mode, and increases with the heating power. The detachment density threshold normalized to the Greenwald density limit is lower at a high plasma current.

With the rapid promotion of big data on the Internet, the construction of “big data” in all walks of life has begun to take root. With the continuous rise of smart scenic spots and smart tourism, it is possible to obtain massive tourism big data. The purpose of this paper is to analyze the construction and application strategy of tourism big data based on the promotion of tourism cultural resources in Qiqihar. First of all, it analyzes the advantages and applicability of spark big data platform, and expounds the system module functions from three main aspects: background management module, information service module and big data analysis module. After studying the algorithm of scoring function, it selects the most commonly used centralized data storage engine on MySQL 5.6.17 for research and test. The experimental results show that the InnoDB storage engine takes 10 to 100 times more time than other engines, and the archive storage engine has the advantages of compressing storage and saving space, which is very suitable for storing visitors’ access information. The platform collects the cultural resources of Qiqihar, a new tourism city, through fine classification and index of resources, graphic and multimedia.

The theory of superlubricity brings a new idea and direction to solve the problem of wear and tear of high-speed cutting tools. According to the superlubricity theory, a new type of cutting fluid based on hexadecyl dimethyl-ammonium bromide was developed by combining superlubricity agent and cutting fluid. Furthermore, taking the cutting of titanium alloy as the object, high speed cutting tests of the new type of cutting fluid were carried out. Finally, a large number of comparative analyses were carried out based on the experimental results. The research shows that the new type of cutting fluid has better cooling and lubrication effect, and can play a good role in reducing friction of cutting tool and improving surface quality of workpiece. The optimum concentration range of hexadecyl dimethyl-ammonium bromide is 2%-4%.

Water allocation refers to the gradual allocation of the total available water resources or the amount of water that can be allocated to the administrative area, and determines the share of water consumption or the share of water used for living and production in the administrative area. The total amount of available water resources includes the amount of surface water resources and the amount of groundwater resources that can be exploited, minus the overlap between the two. Aiming at the water allocation problem of the Juzhang River, this paper discusses the basic principles of water allocation and the technical route of water allocation plan formulation. A water allocation plan for the Juzhang River Basin was drawn up through steps such as supply and demand forecasting and supply and demand balance analysis. The research can provide a certain reference for the development of water allocation schemes in small and medium-sized river basins.

According to the operational safety characteristics of marine nuclear power plant and the nuclear safety rating needs of nuclear ships in case of abnormal events during sea navigation, the rating evaluation standards are established referring to the international nuclear event rating table, which consider three aspects of “radioactive safety impact”, “defense in depth capability impact” and “power output impact” in abnormal events. The potential common cause characteristics of the event are additionally considered. Then the rating procedure for nuclear safety events of marine nuclear power plant is proposed. The study is of great significance for accurately evaluating the severity of abnormal events and effectively guaranteeing nuclear safety of marine nuclear power plant.

With the progress of aerospace technology, unmanned aerial vehicles (UAV) are gradually showing incomparable advantages over manned aircraft. However, the safety interval of formation flying has always puzzled us. In order to solve this problem, this paper mainly studies the collision risks of three UAVs in flight considering the two factors of wind and positioning error. It provides a reference for the research on the of flight safety interval UAV formation.

In order to realize the rapid and accurate real estate traceability of rice in Heilongjiang Province, this paper combines computer vision technology and near-infrared spectral data mining technology to the five major production areas of Heilongjiang Province, the five major production areas, Chahayang production area and Jiansanjiang production. A total of 150 grains of rice were analyzed and studied. In this study, based on the fusion of generalized Cartesian product feature, the feature of rice shape based on rice image and the characteristics of rice near-infrared spectral data were merged, and the classification of rice origin was carried out by using support vector machine algorithm. Finally, the accuracy of the model is 90.7%. The experimental results show that the method can be used as a preliminary application to reach the classification of rice.

The diffusion-oriented disaster system in spatial-temporal networks can be used to excavate the chain relationship between disaster nodes for using the similar space vectors. A methodological approach to analyze the vulnerability of interdependent infrastructures has been introduced. In this paper, the main purpose is to develop the diffusion process and path model of disaster system. Based on spatial-temporal factors, a model for identification of risk of a region is built. It describes the relationship between distance and time in the diffusion process of disaster system. Furthermore, to demonstrate the path of disaster spreading using the improved algorithm of the ant colony. The results show that the diffusion of disaster system is a typical spatial-temporal unified diffusion process, the space distance can hinder the spread of the disaster, and the number of the affected nodes in the region is a negatively exponential relationship with the distance factor. The application of ant colony optimal algorithm to the research of disaster diffusion path has high accuracy and practicability.

In order to simulate engineering machinery (such as mining machinery, feed pellet machine, building machinery and so on), which existence of different degrees of high temperature and humid corrosion three-body abrasive wear behavior in the laboratory environment. In view of the current three-body abrasive wear testing machine cannot simultaneously take into account the composite conditions characteristics of the three-body abrasive wear behaviour, high temperature and humidity, and make the optimization design, based on the MLD-10 dynamic abrasive wear tester. It includes corrosion and wear groove, fluid medium, temperature measuring and controlling device, stirring device, etc. A three-body abrasive wear testing Machine that can control temperature and humidity. Subsequently, the simulated working condition test of the ring die of feed pellet machine were carried out. The test results show that the wear appearance of the test sample is basically consistent with that of the real ring die of feed pellet machine. It indicates that the developed testing machine can simulate the high temperature and humid three-body abrasive wear behavior, and has good reliability and applicability.

The ability to tailor the bandgap of III–V compound semiconductors spatially, across the wafer is highly desirable for monolithically integrating photonic components with multi-functions. Using rapid thermal annealing with SiO2 and TiO2 capping layers as a selective area intermixing technique, we have demonstrated selective area bandgap tuning of III–V quantum dot (QD) material on a silicon (Si) substrate. Electrically pumped InAs/GaAs QD lasers directly grown on Si with dual-wavelength lasing emissions of 1275 and 1313 nm have been fabricated by this technique. This result indicates that the selective area intermixing technique can potentially be used in optical integrated circuits for Si photonics.

Nano-noble metal materials loaded metal oxide greatly reduce application costs, improve catalytic performance and sensing efficiency compared with oxide substrates. A simple and efficient load method plays an important role in promoting its commercialization. Nano-tungsten oxide is a kind of excellent gas sensing materials and it had been widely used. Noble metal loading can form abundant active centers on the surface of tungsten oxide and become an effective way to improve its gas detecting performance. The complexity and high cost of the loading methods hinder the its application and commercialization on supported catalysts. In this paper, Au/WO2.6 composites with high loading rate were prepared on layered tungsten oxide nano-flakes by a simple and low-cost method. The gas sensitivity of WO2.6 to ethanol and formaldehyde without Au and with Au were tested. The results show that the loading rate is the highest after reaction for 24 hours. The gas sensitivity of Au loaded WO2.6 is significantly improved. The sensitive mechanism on Au/WO2.6 composite were discussed in our work.