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A temperature field analysis method is developed for the cabin of high-speed missile. The high fidelity three-dimensional model of the thermal protection system is build based on the finite element method, including structure and equipments inside the cabin. The model can express the heat conduction path, radiation relationship and the heat capacity of the equipment. The aero-heating and heat transfer are solved simultaneously. The convection coefficient relevant to experiment is used to simulate the heat transfer of the gas in the cabin. It can be used to large-scale engineering calculation for the thermal protection system of high-speed aircraft. The numerical example of a head cabin for high-speed missile shows that the obvious regional characteristics of the surface temperature outside the cabin is presented, which reflects the coupling effect of aero-heating and cabin structure. The temperature of the equipment in the cabin rises due to radiation and convection heat transfer. Heat capacity of the equipment and natural convection in the gap have obvious influence on the rate and amount of temperature rising. The developed APDL command stream can integrate commercial software of CAD and CAE. It is suitable for large and complex engineering structure because of the advantages such as high computational efficiency and strong portability.

Haze degrades obscures and content information of sea surface images, which can negatively impact the navigation safety of the intelligent ship in real-time systems. Therefore, it is imperative to develop algorithms that effectively remove haze and make the intelligent ship have higher environmental adaptability. In this paper, we propose a novel Multi-scale Concatenated Attention Network (MCA-Net) to address this problem. Specifically, we use the concatenation operation to connect multi-scale residual blocks (MRB), while introducing the channel attention mechanism for guiding the hazy region feature extracting. Extensive experiments on both synthetic datasets and real sea surface images, which demonstrate our proposed method outperforms are better than other recent dehazing approaches.

Layered materials embrace rich intercalation reactions to accommodate high concentrations of foreign species within their structures, and find many applications spanning from energy storage, ion exchange to secondary batteries. Light alkali metals are generally most easily intercalated due to their light mass, high charge/volume ratio and in many cases strong reducing properties. An evolving area of materials chemistry, however, is to capture metals selectively, which is of technological and environmental significance but rather unexplored. Here we show that the layered telluride T[2]PTe[2] (T=Ti, Zr) displays exclusive insertion of transition metals (for example, Cd, Zn) as opposed to alkali cations, with tetrahedral coordination preference to tellurium. Interestingly, the intercalation reactions proceed in solid state and at surprisingly low temperatures (for example, 80 °C for cadmium in Ti[2]PTe[2]). The current method of controlling selectivity provides opportunities in the search for new materials for various applications that used to be possible only in a liquid., 重金属を固体中で選択的に吸収する材料の発見 : 電子機器からの新たな金属回収法などの開発に期待. 京都大学プレスリリース. 2016-12-20.

Cu3 V2 O8 nanoparticles with particle sizes of 40-50 nm have been prepared by the co-precipitation method. The Cu3 V2 O8 electrode delivers a discharge capacity of 462 mA h g(-1) for the first 10 cycles and then the specific capacity, surprisingly, increases to 773 mA h g(-1) after 50 cycles, possibly as a result of extra lithium interfacial storage through the reversible formation/decomposition of a solid electrolyte interface (SEI) film. In addition, the electrode shows good rate capability with discharge capacities of 218 mA h g(-1) under current densities of 1000 mA g(-1) . Moreover, the lithium storage mechanism for Cu3 V2 O8 nanoparticles is explained on the basis of ex situ X-ray diffraction data and high-resolution transmission electron microscopy analyses at different charge/discharge depths. It was evidenced that Cu3 V2 O8 decomposes into copper metal and Li3 VO4 on being initially discharged to 0.01 V, and the Li3 VO4 is then likely to act as the host for lithium ions in subsequent cycles by means of the intercalation mechanism. Such an "in situ" compositing phenomenon during the electrochemical processes is novel and provides a very useful insight into the design of new anode materials for application in lithium-ion batteries.

Herein, we explored a novel ratiometric fluorescent probe TP-FA, which could detect FA not only in aqueous solution, but also in air by loading on the fabric and cotton. The test cotton displayed the much faster response to FA than the test fabric and test solution. When the test cotton was exposed to FA vapor, the Aza-Cope reaction of TP-FA with FA changed the emission color from blue to green within 45 min by the combined aggregation-induced emission (AIE) and intramolecular charge transfer (ICT) effects. Moreover, the test cotton exhibited the high selectivity to gaseous FA, and it could point out the concentration of FA vapor according to the emission color.

The controlled deposition of single Pt atoms on a substrate affords a well-dispersed and robust CO oxidation catalyst, for which spectroscopic characterization can unravel detailed reaction pathways.

The fluorite-like [Bi2O2](2+) layer is a fundamental building unit in a great variety of layered compounds. Here in this contribution, we presented a comprehensive study on an unusual Aurivillius phase Bi3.6V2O10 with respect to its defect chemistry and polymorphism control as well as implications for fast oxide ion transport at lower temperatures. The bismuth oxide layer in Bi4V2O11 is found to tolerate a large number of Bi vacancies without breaking the high temperature prototype I4/mmm structure (γ-phase). On cooling, an orthorhombic distortion occurs to the γ-phase, giving rise to a different type of phase (B-phase) in the intermediate temperature region. Cooling to room temperature causes a further transition to an oxygen-vacancy ordered A-phase, which is accompanied by the charge ordering of V(4+) and V(5+) cations, providing magnetic (d(1)) and nonmagnetic (d(0)) chains along the a axis. This is a novel charge ordering transition in terms of the concomitant change of oxygen coordination. Interestingly, upon quenching, both the γ- and B-phase can be kinetically trapped, enabling the structural probing of the two phases at ambient temperature. Driven by the thermodynamic forces, the oxide anion in the γ-phase undergoes an interlayer diffusion process to reshuffle the compositions of both Bi-O and V-O layers.

Electrides are unique in the sense that they contain localized anionic electrons in the interstitial regions. Yet they exist with a diversity of chemical compositions, especially under extreme conditions, implying generalized underlying principles for their existence. What is rarely observed is the combination of electride state and superconductivity within the same material, but such behavior would open up a new category of superconductors. Here, we report a hexagonal Nb5Ir3 phase of Mn5Si3-type structure that falls into this category and extends the electride concept into intermetallics. The confined electrons in the one-dimensional cavities are reflected by the characteristic channel bands in the electronic structure. Filling these free spaces with foreign oxygen atoms serves to engineer the band topology and increase the superconducting transition temperature to 10.5 K in Nb5Ir3O. Specific heat analysis indicates the appearance of low-lying phonons and two-gap s-wave superconductivity. Strong electron–phonon coupling is revealed to be the pairing glue with an anomalously large ratio between the superconducting gap Δ 0 and T c, 2Δ 0/k B T c = 6.12. The general rule governing the formation of electrides concerns the structural stability against the cation filling/extraction in the channel site. Coexistence of electride behavior and superconductivity is observed in a hexagonal phase of a Nb5Ir3 intermetallic with tunable electronic properties by introducing foreign atoms. A team led by Yaoqing Zhang and Hideo Hosono from Japan Science and Technology Agency and Tokyo Institute of Technology report a new hexagonal phase in the phase diagram of Nb–Ir binary intermetallics with interesting interplay of superconductivity and electride state. The electride state is formed by electrons detaching from the atoms but localizing in a one-dimensional channel space. This electride becomes a superconductor below a transition temperature of about 9.4 K, which could be enhanced to 10.5 K upon filling interstitial cavities with foreign oxygens. The results suggest a general rule governing the formation of electrides and form the basis for novel stable functional electrides.

We report robust superconducting state and gap symmetry of Nb5Ir3O via electrical transport and specific heat measurements. The analysis of specific heat manifests that Nb5Ir3O is a strongly coupled superconductor with Δ C / γ n T c ∼ 1.91 and double s-wave superconducting gaps of 2 Δ L ( 0 ) / k B T c ∼ 6.56 and 2 Δ S ( 0 ) / k B T c ∼ 2.36 accounting for 90% and 10%, respectively. The ( C p − γ n T ) / T 3 vs. T plot shows a broad peak at ∼23 K, indicating phonon softening and the appearance of low-lying phonon mode associated with the interstitial oxygen. This behavior explains the monotonic increase of T c in Nb 5 Ir 3 O ( 1 − δ ) by strengthening the electron–phonon coupling and enlarging the density of states at Fermi level. The Hall coefficient is temperature independent below 200 K, and changes its sign from positive to negative above 250 K, suggesting that carrier is across the hole- to electron-dominant regions and the multi-band electronic structures. On warming, the resistivity shows a gradual crossover from T 2 - to T 3 -dependence at a critical temperature T * , and a broad peak at a temperature T p. The reduced T c under pressure is linearly correlated with lattice parameters c/a ratio and T p, suggesting the important phonon contributions in Nb5Ir3O as a phonon-medicated superconductor. Possible physical mechanisms are proposed.

In contrast to the rich oxygen nonstoichiometry in vanadium oxides, we report here an interesting Bi4V2O(11-δ) oxide system whose vanadate layer allows only a narrow oxygen deficiency range. Beyond δ = 0.4, reduction of Bi4V2O(11-δ) does not proceed in the V-O layer, but instead suddenly switches to the Bi-O layer by precipitation of metallic bismuth. A new structure is realized for 0.4 ≤ δ ≤ 1, and its ordered V(4+) cation forms a rigid V(4+)/V(5+) = 2/3 pair giving rise to one-dimensional magnetism that can be understood in terms of an S = 1/2 antiferromagnetic Heisenberg chain model. In situ X-ray diffraction measurement yielded the first phase diagram for the system of current study and revealed the unusual phase relation as a function of oxygen nonstoichiometry. It is suggested that at higher temperatures than 570 °C all compositions would be unified into an oxygen disordered tetragonal phase, whose implication for oxide ion mobility could have significant impact on our understanding of ionic conduction.

Synthetic hydrocarbon fuels from CO2/H2O are proposed as alternatives to hydrogen as an energy carrier to enable a carbon neutral energy cycle, given their inherent advantages of high H/C ratio and convenience of storage and transportation. Here we demonstrate the successful electrochemical reduction of CO2 into CO and CH4 in a proton conducting solid oxide electrolyser based on BaCe0.5Zr0.3Y0.16Zn0.04O3 − δ (BCZYZ) electrolyte and a composite iron/iron oxide cathode. The production of CH4 and CO reaches 0.07 and 3.25 ml min−1 cm−2, respectively, with 1.5 A cm−2 at 614 °C. The overall CO2 conversion rate in the electrochemical reduction process is 65%.

Sodium-ion batteries (SIBs) have attracted much interest as a low-cost and environmentally benign energy storage system, but more attention is justifiably required to address the major technical issues relating to the anode materials to deliver high reversible capacity, superior rate capability, and stable cyclability. A SnSe/reduced graphene oxide (RGO) nanocomposite has been prepared by a facile ball-milling method, and its structural, morphological, and electrochemical properties have been characterized and compared with those of the bare SnSe material. Although the redox behavior of SnSe remains nearly unchanged upon the incorporation of RGO, its electrochemical performance is significantly enhanced, as reflected by a high specific capacity of 590 mA h g(-1) at 0.050 A g(-1) , a rate capability of 260 mA h g(-1) at 10 A g(-1) , and long-term stability over 120 cycles. This improvement may be attributed to the high electronic conductivity of RGO, which also serves as a matrix to buffer changes in volume and maintain the mechanical integrity of the electrode during (de)sodiation processes. In view of its excellent Na(+) storage performance, this SnSe/RGO nanocomposite has potential as an anode material for SIBs.

According to the characteristic of responding-antisubmarine, this paper analyzes submarine maneuvering model and anti-submarine patrol route model combining anti-submarine patrol aircraft and using the method of magnetic finder searching under the condition of responding-antisubmarine, establishes the effectiveness model of anti-submarine patrol aircraft by using magnetic finder to check submarine so as to lay a foundation for magnetic finder optimization. I. INTRODUCTION Responding-antisubmarine refers to combat operations that anti-submarine patrols at the specified position on standby and when get the submarine activity information, flies to the sea area finding sub and searches submarine. Its characteristic is that we know the position of the submarine at a certain moment before search. Antisubmarine patrol aircraft flight speed is fast, so when implement responding-antisubmarine, we can greatly reduce the delay time (1). At the same time, magnetic finder is not affected by acoustic environmental impact, continuous search, high positioning accuracy, etc.; therefore anti-submarine patrol aircraft can immediately put search assignments after reaching the responding waters with a few minutes magnetic compensation flight by using magnetic finder. This narrows the scope of submarine exercise, thus improves the probability of submarine finding. So responding-antisubmarine is the main search campaign pattern of anti-submarine patrol aircraft using magnetic finder (2). II. SUBMARINE MANEUVER MODEL A. Submarine's initial position For other forces such as surface ships, sonobuoy, there is a great deal of uncertainty for the first time contact's submarine location data. It is generally believed the submarine's initial position is of two-dimensional Gaussian distribution, and distribution center is the initial position of the point (3). Set the initial position of distribution center in the origin of coordinates, and the expected value is 0. The initial position point ( ) 0 0 , y x meets independent identical distribution in X, Y directions. If the mean square error is 0 σ σ σ = = y x , the joint probability density function of the initial position point

Polycrystalline Bi4V2O11-δ samples are prepared by solid state reaction of a stoichiometric mixture of Bi2O3, V2O3, and V2O5 (sealed quartz tube, 600 °C, 3 d).

In this paper, the structure and principle of a synergetic expert system for fault diagnosis (SESFD) are introduced in view of the limit of present expert system in application. SESFD is composed of four subordinate expert systems (SES) and a meta expert system (MES). MES controls and coordinates the work of SESs. Object-oriented programming has been used in system design. SESFD surmounts the brittleness of the single expert system and has a wide application prospective. >

Considering the specific characteristics of diagnostic problems, based on set-covering and certainty factors, a multi-faults diagnosis model is presented and a solving algorithm of the model is given in this paper. It makes up for the shortcoming of "single-fault hypothesis" which most diagnostic methods have used. The model is an effective attempt for multi-faults problem solving. >

Synthetic fuels produced from CO2/H2O are an attractive alternative energy carrier. Here we demonstrate a novel strategy to electrochemically convert CO2/H2O into hydrocarbon in a single step in an oxygen-ion conducting solid oxide electrolyser. Methane was directly synthesized in an efficient electrolyser with configuration of (anode) (La0.8Sr0.2)0.95MnO3−δ/YSZ/La0.2Sr0.8TiO3+δ (cathode) by combining coelectrolysis of CO2/H2O and in situ Fischer–Tropsch-type synthesis. We demonstrate a high Faradaic yield of CO/H2 and lower methane yield, which shows that the limit on conversion efficiency comes from the heterogeneous catalysis process. Electrochemical results also show that the electrochemical reduction of La0.2Sr0.8TiO3+δ cathode is the main process at low electrical voltages while the coelectrolysis is the main process at high voltages.