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It is of great significance to study the mixing combustion characteristics of solid rocket ramjet for better organizing the secondary combustion of the air flowing into the inlet and the combustion-rich gas, enhancing the mixing degree of the supplementary combustion chamber, and improving the combustion efficiency. In this paper, the L-W model is used as the boron particles ignition combustion model. Combined with the UDF function of fluent, the boron particle ignition combustion program is self-programmed, the finite rate/eddy dissipation model is used as the gas combustion model, and the Realizable k-e turbulence model is used as the turbulence model. The numerical simulation was carried out under the cold flow state and the hot flow state, and the flow field distribution and parameters were obtained, and the mixing characteristics were analyzed. The error of simulation results and test results shows that that the numerical simulation results are in good agreement with the experimental results. By comparing the combustion efficiency and mixing degree, it is found that generally, When the mixing effect is not good, the combustion efficiency must be bad; When the mixing effect is good and the mixing degree is high, the combustion efficiency may be high.

To address the current problem of insufficient risk level analysis of gasifier systems, an evaluation method combining the cloud model and dynamic Bayesian network is proposed, taking the gasifier system as the evaluation target, using the cloud model to discretize continuous data, and setting each risk factor in the evaluation system as a node in the dynamic Bayesian network to build a dynamic Bayesian network. The entropy weight method is used to calculate the weight of each risk indicator, the maximum likelihood estimation method is used to process the affiliation degree obtained from the cloud model, and the probability obtained by the affiliation-probability conversion method is input into the dynamic Bayesian network as evidence. Finally, the risk prediction assessment for the gasifier system is completed by using the features of forwarding and backward inference of the dynamic Bayesian network, combined with the comprehensive analysis of importance. The study shows that human maintenance efficiency, equipment integrity, gasifier pressure, and oxygen-coal ratio are the weak points that need to be focused on in the operation of the system.

Aiming at the problem that the existing calculation methods have a big difference in the calculation results and the actual calculation results, in order to improve the accuracy of the calculation results, the time series production simulation theory is introduced, and the calculation method of the consumption capacity of photovoltaic distribution networks is studied. According to the actual operation of the distribution network, this paper adjusts the power supply pattern of the photovoltaic distribution network; then, this paper checks the frequency regulation capacity of the photovoltaic distribution network; finally, the time series production simulation is introduced to simulate the production of the photovoltaic distribution network with the absorption capacity. The comparative experiment shows that the new calculation method is more accurate than the existing calculation method based on uncertainty optimal power flow, and it can provide a data basis for the planning and construction of photovoltaic distribution networks.

Based on the importance of the safe operation of the mine hoist mechanism, an adaptive control method based on Fuzzy Sliding Mode Control (FSMC) was applied to synchronize the large-amplitude response of geometrically nonlinear elastic wire rope in mine hoist systems. To efficiently and precisely synchronize the lateral vibration of a wire rope under the adaptive synchronizing method, the control equation of the elastic wire rope was given considering the large von Karman geometrical deformation, and it was converted to a six-dimensional nonlinear dynamical system using third-order Galerkin discretization. Based on this dynamic system, the existing FSMC is improved, so that the improved control strategy will be available for the active dynamic control of multidimensional nonlinear dynamical systems. The research shows that the control strategy can effectively synchronize the large-amplitude response of wire rope, thus providing the basis for dynamic design, fault diagnosis, and safe operation of the mine hoist system.

In order to meet the needs of the development of high-performance micro-engine, the micro-turbine is faced with the technical challenge of high-load and transonic flow. At present, the flow characteristics and loss mechanism of high-load micro-impeller are not clear. In this paper, the flow characteristics of high-load micro-turbine rotor are studied. The results show that the loss in rotor trailing edge is the main factor that affect the operation of the micro transonic turbine, and the key to reduce the loss is to reduce the wake diffusion range and the Mach number in front of the extended shock wave. By adjusting the local curvature of the front in front of the incident point of the back-extension wave in the throat of the suction surface, the convergent-divergent ratio is in the range of 1.04 ~ 1.08. Meanwhile, the Mach number of wave front can be reduced by 3.4% and the reflection of trailing edge inward extension can be effectively suppressed, and the total rotor pressure loss coefficient can be reduced by 14.1% at most. The thickness has an important effect on the wave strength and wake loss in the trailing edge. When the relative thickness of the trailing edge decreases by 50%, the maximum Mach number on the suction surface decreases by 7.8%, the turbine stage efficiency increases by 1.92%, and the relative thickness of trailing edge is 0.124~0.185, the studied micro-transonic turbine performs better.

Interfacial charge recombination is a main issue causing the efficiency loss of the perovskite solar cells (PSCs). Here, ferroelectric Ba0.75Sr0.25TiO3 (BST) is introduced as a polarization tunable layer to promote the interfacial charge transfer of the PSCs. The coexistence of ferroelectric polarization and charge carriers in BST is confirmed by density functional theory (DFT) calculations. Experimental characterization demonstrates the polarization reversal and the existence of domain in BST film. The BST film conductivity is tested as 2.98 × 10−4 S/cm, which is comparable to the TiO2 being used as the electron transporting layer (ETL) in PSCs. The calculations results prove that BST can be introduced into the PSCs and the interfacial charge transfer can be tuned by ferroelectric polarization. Thus, we fabricated the BST-based PSCs with a champion power conversion efficiency (PCE) of 19.05% after poling.

Pore pressure prediction is of fundamental importance in petroleum exploration and production operations. Because there is no direct method to measure pore pressure in shale, the indirect method (the equivalent depth method) for estimating pore pressure from sonic velocity data is widely used. It has been found in the application of the equivalent depth method in several Chinese sedimentary basins that the calculated pressures from sonic logging data are very consistent with the DST or RFT pressures measurements in some basins and are very divergent in others. The consistence of calculated and measured excess pressures in the basin with different excess pressure generation mechanisms such as in the cases in Tarim basin, Bohai Bay basin and Jiuquan basin showed that the pressure calculated by the equivalent depth method accounts for all excess pressure generation mechanisms such as disequilibrium compaction, tectonic compression, aquathermal pressuring, hydrocarbon generation and clay diagenesis. The divergence of calculated and measured excess pressures was found in the organic-rich source rocks in Triassic in Ordos basin and in Cretaceous in Songliao basin. Compared with common shales, organic-rich shales are composed of more solid organic matter, which can influence the sonic velocity values. Our study shows that the sonic velocity decreases dramatically when the TOC is higher than 2%. So the pore pressures calculated by the equivalent depth method from sonic velocity data may much higher than the actual pressures in organic-rich shale. The use of the equivalent depth method may mislead in predicting pore pressure of organic-rich shale without considering the influence of total organic carbon content.

Considering the difficulty of large computation and the characteristic of helicon plasma, a modified collisional-radiative model was proposed for the diagnosis of low-temperature helicon argon plasma. A simplified 47-level is proposed due to the lack of experimental support of transition data at high levels as well as heavy computation to obtain macroscopic parameters of helicon argon plasma, e.g., electron number density ne and electron temperature Te. A creative twice-matching method is proposed in the model because the current double-line intensity ratio method shows significant sensitivity in diagnosing low-temperature electrons. Calculations based on this model shows the spectrum intensity depends on the electron temperature as well as density for low-temperature plasma, especially when it’s below 6eV. The twice matching process based on the priori knowledge chooses 15 spectrums cognizable within the wavelength from 680nm to 860nm, adopting the absolute values of the lines to match with the results calculated by the collisional-radiative model. This method greatly reduces the average error to 13.7%. The result indicates that the precision of the electron temperature and density has been improved a lot and the relative errors are 25% and 40%, respectively. Within the accuracy range above, the research shows when RF power is 500-800W and the pressure is 0.5-1.3Pa, the electron number density rises with the increasing RF power and decreases with the increasing magnetic field strength (450-900G) and gas pressure. Moreover, comparing to the number density of electrons, the electron temperature changes less and rises with the decreasing pressure.

As a tight sandstone gas reservoir of Su-6 well block in Sulige gas field, part of the gas wells have a poorer production performance with a faster decline rate of formation pressure and production, which is inconsistent with static reservoir parameters of gas well. In order to improve the productivity of gas well, on the base of static and dynamic classification of 232 gas wells, the reasons of inconformity between production performance and static reservoir parameters are analyzed from the four aspects of sand body connectivity, reservoir heterogeneity, gas saturation and fluid accumulation in wellbore. The results show that the main reasons causing the inconformity are the strong heterogeneity and poor sand body connectivity, and the secondary reasons are fluid accumulation in wellbore and low gas saturation. The results of this paper is of great significance to improve the productivity of gas wells and guide the development of ultra-low permeability gas reservoir.

Due to the complexity, multi-source and heterogeneity of mine safety scene perception information, the mine safety monitoring system has some problems, such as slow perception, communication lag, lack of effective information extraction and intelligent decision-making, a mine safety situation perception self configuration system based on the Internet of things is proposed in this paper, the architecture and perception model of mine safety situation perception system are established, and the embedded neuron is designed mine safety monitoring system based on perceptual node and distributed neural network. The unscented Kalman filter is used to adjust the BP neural network to reconcile and process the multi-sensor parameter information. The simulation results show that the system has good fault tolerance and high precision of intelligent decision-making, which plays an important role in improving mine intelligent level and safety production.

A macroscopic silver nanowire (AgNW) network is grown by solid state ionics method. The ion flow during growth of the AgNW network is controlled by maintaining a current in the order of 10-7 A. Scanning electron microscopy (SEM) analysis reveals that the growth direction of AgNWs in the network is irregular and spread evenly in all directions and the nanowires are 40-160 nm in diameter. The microcosmic mechanism of silver nanostructures grown by the solid state ionics method is established by real time and in situ SEM analysis of the growth process of the AgNW networks. To study the photoelectric properties of the network, a self-supported AgNW network sample (∼1 mm wide and 8 mm long) is irradiated with lasers of different wavelengths of 375, 405, 532, 633, 808, and 1064 nm and 10.6 μm, and changes in the current between the two ends of the sample are recorded. The network displays negative photoconductance effect, and the maximum light responsivity is 43 mA W-1. The network displays light responsivity in the ultraviolet light-to-mid-infrared light region, with response times of tens of milliseconds. These findings indicate that the AgNW network has broad application prospect in ultra-wide spectrum photoelectric detection.

With the advent of the era of 5G big data, it is not only necessary to mine valid data in mass information, but also to classify it. Mining and classifying information can be used as an important basis for decision making. Making correct and efficient decisions on agricultural planting can not only improve agricultural production efficiency, but also lay the foundation for the realization of smart agriculture. This paper will compare the improved algorithm, which is called MIND, with the algorithms in other literaturesby experiments. Through calculations in agricultural big data such as temperature, humidity, wind, and weather, it is demonstrated that the improved algorithm is more suitable for agricultural planting decisions.

The spectral attenuation of a 400-nm probe laser propagating through a femtosecond plasma in air is studied. Defocusing effect of the low-density plasma is an obvious effect by examining the far-field patterns of the 400-nm pulse. Besides, the energy of 400-nm pulse drops after interaction with the plasma, which is found to be another effect leading to the attenuation. To reveal the physical origin behind the energy loss, we measure fluorescence emissions of the interaction area. The fluorescence is hardly detected with the weak 400-nm laser pulse, and the line spectra from the plasma filament induced by the 800-nm pump pulse are clearly shown. However, when the 400-nm pulse propagates through the plasma filament, the fluorescence at 391 nm from the first negative band system of N 2 + is enhanced, while that from the second positive band of neutral N2 at 337 nm remains constant. Efficient near-resonant absorption of the 400-nm pulse by the first negative band system occurs inside the plasma, which results in the enhanced fluorescence. Furthermore, the spectral attenuation of the 400-nm probe laser is measured as a function of the pump–probe time delay as well as the pump-pulse energy.

In the rolling of four-roll mills, there are often damages in bearing such as the burning and adhesion failure. Domestic and foreign scholars have done a lot of calculations and experiments on this, and believe that when the support system of the roll neck (roll neck, bearing and bearing seat) suffers the roll bending force, the four-row cylindrical roller bearing suffering the radial bending force may be eccentric due to the hyperstatic structure of the mechanism in which the bearing block cannot be synchronously bent with the roller neck, thereby causing bearing damage. In this paper, the integrated model of the roll neck support system of the roll is established by SolidWorks, which is introduced into ANSYS-Workbench for contact surface setting, loading and constraint, and finally the roll neck bending deflection and bearing roller contact stress are analyzed and verified, which confirmed the validity of integrated deformation and mechanical analysis of roll neck support system by finite element method.

This study aims at examining the performance of the ClO2 on treating ballast water of Dalian new port area foreign trade oil pool in the cases of different experimental parameters, and Cylindrospermopsis raciborskii (CR), Gymnodinium catenatum (GC) and Gymnodinium cf. mikimotoi (GCM) are used for this experiment. The results shows that under certain test condition, the removal rates are in proportion to the dosage of ClO2 and reaction time, and inversely proportion to pH value, humic acid and ammonia nitrogen content. Accordingly, on operating at the optimal dosage of ClO2 and parameters of experiment, this process is proven to be an effective technology to remove these three algae and organic compounds in ballast water. In ballast water, the removal ability of ClO2 for these three algae is less sensitive to pH value, humic acid and ammonia nitrogen content than to ClO2 dosage and reaction time. Removing GC, GCM and CR with ClO2 are attributed to the second order reaction. Investigating the performance of such process, could serve to develop management strategies that enable mitigating the impacts of harmful substance in ballast water and help improving and ensuring quality of ballast water.

Fast and sensitive detection of terahertz radiation is notoriously difficult, especially the detection at the ambient condition. Here, we fabricated bolometric terahertz photodetectors based on suspended carbon nanotube (CNT) fibers. Because the CNT fibers exhibit a very small heat dissipation area, the heat transport from the CNT fibers to the air is negligible. It ensures the devices can work well at the ambient condition. Additionally, the CNT fibers demonstrate a high responsivity up to 0.54 A W−1 and a short response time of 200 μs. This implies a performance that is competitive among the terahertz photodetectors based on CNT.

With the change of micro environmental variables such as internet technology, AI technology, the upgrade of education consumption, there has been a profound change in education, and then the value network created by undergraduates, teachers, employers and other stakeholders will be also changed. The crisis faced by education is the multiple trust crises among stakeholders, and the contradiction between the personal needs of undergraduates (personal desire for development, personal maturity cycle, personal growth rate, etc.) and the One-size-fits-all teaching is the main aspect of the multiple trust crises. Therefore, establishing the concept of adaptive learning and shifting the focus of reform from One-size-fits-all teaching to personalized education is the way for educational reform in the future. The reform should firmly establish the principles of cognitive science obeying, interest activating, diversity cultivating, and balance keeping. Evidence-based education, mastery learning, etc. are the core elements of design of adaptive learning environment. The theoretical base of this research is Piaget’s cognitive developmental psychology and adaptive learning theory. It applies educational theories and educational techniques, such as evidence-based education, OBE, mastery learning, etc., to the construction of the adaptive learning environment. It provides an overview of the main modules and algorithms of the environment, with the aim of using the top-level design to enable the hidden functions of education by the soft environment.

Temperature and excitation dependent photoluminescence (PL) of InGaN epilayer grown on c-plane GaN/sapphire template by molecular beam epitaxy (MBE) has been systematically investigated. The emission spectra of the sample consisted of strong multiple peaks associated with one stimulated emission (SE) located at 430 nm and two spontaneous emissions (SPE) centered at about 450 nm and 480 nm, indicating the co-existence of shallow and deep localized states. The peak energy of SE exhibiting weak s-shaped variation with increasing temperature revealed the localization effect of excitons. Moreover, an abnormal increase of the SPE intensity with increasing temperature was also observed, which indicated that the carrier transfer between the shallow and deeper localized states exists. Temperature dependent time-resolved PL (TRPL) demonstrated the carrier transfer processes among the localized states. In addition, a slow thermalization of hot carriers was observed in InGaN film by using TRPL and transient differential reflectivity, which is attributed to the phonon bottleneck effect induced by indium aggregation.

Nanoscale morphology of vanadium dioxide (VO2) thin films can be controlled to realize smooth ultrathin crystalline films (

Herein, we propose a new strategy to fabricate gold (Au) micro/nanostructure arrays by photocatalytic solid-state electrochemical reaction between superionic conductor RbAg4I5 and Au films. The Au and RbAg4I5 films were successively deposited on a clean quartz substrate by vacuum thermal deposition method. A copper microgrid possessing periodic holes 100 μm in diameter was put above the RbAg4I5 film as a mask plate, whereupon irradiation from a 405 nm wavelength laser was used to diffuse gold ions (Au+ ions) into vacant silver sites of RbAg4I5 and transfer Au+ through ion passageways in the RbAg4I5 film. When the laser was turned off, the Au+ ions were easily reduced due to low activity compared to the silver (Ag+) ions. After multiple on/off cycles of the 405 nm laser, the irradiated area of uniform Au film exhibited a periodic structural unit array whose period was the same as that of the mask plate hole array. Atomic force microscope and scanning electron microscope images revealed that a self-assembled needle-like nanostructure array grew perpendicular to the substrate surface inside each circle's structural unit. The height of the grown nanostructure array increased with laser power density. Raman enhancement of the gold nanostructure array as substrate was detected using Rhodamine 6G (R6G) ethanol solutions as probe molecules. The enhancement effect increased with the height of the grown nanostructure array, and could increase by two orders of magnitude greater than that of unirradiated Au film. This strategy offers a new method for the micro/nanostructure processing of gold and provides microscale-array-mediated surface-enhancement Raman-scattering (SERS) substrates comprising Au nanostructures for application in high-sensitivity spectrum analysis.

Veiling glare index (VGI) is an important criterion to evaluate the image quality that can be obtained with an optical system. The VGI can be measured after the design of the optical system. If the measured VGI of an optical system does not meet the requirements, the stray-light suppression must be adjusted to improve its effectiveness. To facilitate this process, we propose a method to calculate the VGI of an optical system during the design stage. In the method, a programme called TracePro is used to model and analyse the optical system using tracing rays, and MATLAB is used to fit the simulation results to obtain the VGI. This method enables analysis and calculation of the VGI before fabrication of the system and provides an accurate technique to evaluate the effectiveness of the stray-light suppression in an optical system.

As an important industrial material, hot-rolled steel has high strength and toughness, and it is easy to process and shape. So it has a wide range of applications in the fields of construction, bridge, shipbuilding and automobile. The surface roughness of hot-rolled steel is a key parameter that need to control and it has a great impact on the performance of the steel. In order to improve the efficiency of hot-rolled steel roughness detection, this paper introduces a method of online roughness detection system based on laser two-dimensional displacement sensor.

Colossal magnetoresistance and giant magnetoresistive memory effect have been demonstrated in the electron-doped manganite superlattices composed of alternatively of G-type antiferromagnetic insulator (G-AFI) layers of CaMnO3 and C-type antiferromagnetic insulator (C-AFI) layers of Ca0.92Ce0.08MnO3. The transport properties of the superlattices strongly depend on the periodicity and the unit cells of each layer. The charge transfer through the interface of the constituent insulators induces appearance of the canted G-type antiferromagnetic metal (cG-AFM) phase in the superlattices. Enhanced colossal magnetoresistance and memory effect emerge in the superlattices composed of the thinner G-AFI layers, which can be attributed to the artificially generated two-dimension-like phase competition between cG-AFM and C-AFI in the charge transfer region. The effective charge transfer through interface provides us an opportunity to control phase separation and thus tailoring electronic properties of electron-doped manganites.

Multiferroic Bi2FeMnO6 epitaxial thin films were deposited on conductive SrRuO3/SrTiO3 (0 0 1) substrate by pulse laser deposition. The Au/Bi2FeMnO6/SrRuO3 capacitor structure was used to investigate the electrical property. Bi2FeMnO6 thin film has a good ferroelectric retention and the downward polarization state. For Bi2FeMnO6 film, different leakage mechanisms play a predominant role under different electric field regions. Ohmic conduction works under 80 kV cm−1. From 80 to 1350 kV cm−1, the leakage mechanism depends on the electric field polarity and Poole–Frenkel emission is the dominant mechanism at negative bias. Schottky emission dominates the leakage current above 1350 kV cm−1. The extracted zero-field ionization energy for Poole–Frenkel emission is ~0.4 eV. A schematic energy band alignment of Au/Bi2FeMnO6/SrRuO3 capacitor was constructed to describe the contribution of Schottky emission.

We report the synthesis of single crystals of α -ZrSb 2 / α -HfSb 2 and their magneto-transport properties. Both of α -ZrSb 2 and α -HfSb 2 exhibit metallic behavior. The T 3 behavior of zero-field resistivity for both compounds below 30 K indicates interband electron-phonon scattering. The magnetoresistance (MR) is found to obey Kohler's rule for ZrSb 2 while the MR of HfSb 2 deviates from this rule. A possible explanation for the results of Kohler's plot is considered, which is confirmed with the results of the Hall effect. The positive linear Hall resistivity of ZrSb 2 suggests hole-type carriers and a mobility of , while the existence of two types of carriers in HfSb 2 is confirmed from the nonlinear Hall resistivity.

Epitaxial SmNiO3−δ thin films were fabricated under various oxygen partial pressures () on (0 0 1)-oriented LaAlO3 substrates by using the pulsed laser deposition method. Continuous control of the metal–insulator transition temperature (T MI) from 350 K to 85 K was achieved by varying from 26 Pa to 0.5 Pa. The reduction of T MI can be attributed to the straightening-out of the out-of-plane Ni–O–Ni bond angle due to the elongation of unit cell volume with decreasing . When > 3 Pa, resistivity anomalies around 200 K are observed in the insulating phase of strained SmNiO3−δ films, suggesting the onset of antiferromagnetic ordering of the Ni sublattices. An electronic phase diagram of the oxygen-deficient SmNiO3−δ films has been established in this work based on the results of the transport measurements.

Highly aligned silver nanowire arrays are synthesized under direct current electric field (DCEF) treatment by a solid state ionics method without any template at normal temperature and pressure. The degree of alignment of the synthesized nanowires increases with increase of the DCEF strength. The mechanism of the effect of the DCEF on the nanowire alignment is discussed briefly. Moreover, the alignment of the individual nanowires in a bundle is further proved by observing the polarization dependence in the experiment of the polarized reflection measurements.

The structural and optical properties of Cu2SnX3 (CTX, X = S, Se) and Cu2ZnSnX4 (CZTX, X = S, Se) thin films have been investigated experimentally. CTX and CZTX thin films were grown on a Mo-coated soda lime glass substrate by annealing the metallic stack precursors prepared by radio-frequency magnetron sputtering. The similar structure of CTX and CZTX causes overlap of the diffraction peaks in the x-ray diffraction (XRD) pattern. Additionally, selenization annealing is an easier procedure than sulfurization annealing. The results of Raman scattering spectroscopy and Fourier transform infrared spectroscopy provide evidence regarding structure and phase identification to complement the information obtained from XRD. Optical characterization demonstrates that CTX has a narrower band gap than CZTX, attributed to band gap evolution from ternary to quaternary compounds with cation occupation. A photoelectric detector and thin film solar cell (TFSC) were prepared with the eco-friendly compounds Cu2SnS3 (CTS) and Cu2ZnSnS4 (CZTS). Device performance for both photoelectric detector and TFSC is improved by integrating CZTS thin film rather than CTS thin film. The simpler structure of a photoelectric detector provides an easy way to detect the quality of the thin film before it is applied to fabricate the whole TFSC structure.

We report on the photoresponse of a graphene-metal contact device under terahertz (THz) illumination. The device has an extremely simple structure consisting of a large-area monolayer graphene stripe contacted with two gold electrodes. A significant position-dependent photovoltage is observed across the device by THz excitation, exhibiting a linear relationship with the incident beam power. Experimental results show that the graphene channel length and the substrate thermal conductivity have obvious influence on the photovoltage amplitude and response time, which is consistent with the photothermoelectric mechanism. This compact and powerless device is expected to have a promising application in THz detection. Our work provides theoretical and experimental evidence for the development of high-performance graphene-based THz photodetectors.

We synthesized single crystals of β-MoTe2 by the chemical vapor transport (CVT) method. Resistivity and magnetoresistivity (MR) have been measured. The MR displays H 2 behavior at low field and linear field dependence at high field, which is different from the quadratic behavior in the sample obtained from the NaCl-flux method. It is suggested that the observed linear MR may originate from disorder. The quality and low-temperature property of β-MoTe2 clearly depend on the growth method. Moreover, the angular-dependent MR reveals the two-fold symmetry of Fermi surface.

Phase is one of the most important parameters of electromagnetic waves. It is the phase distribution that determines the propagation, reflection, refraction, focusing, divergence, and coupling features of light, and further affects the intensity distribution. In recent years, the designs of surface plasmon polariton (SPP) devices have mostly been based on the phase modulation and manipulation. Here we demonstrate a phase sensitive multi-parameter heterodyne scanning near-field optical microscope (SNOM) with an aperture probe in the visible range, with which the near field optical phase and amplitude distributions can be simultaneously obtained. A novel architecture combining a spatial optical path and a fiber optical path is employed for stability and flexibility. Two kinds of typical nano-photonic devices are tested with the system. With the phase-sensitive SNOM, the phase and amplitude distributions of any nano-optical field and localized field generated with any SPP nano-structures and irregular phase modulation surfaces can be investigated. The phase distribution and the interference pattern will help us to gain a better understanding of how light interacts with SPP structures and how SPP waves generate, localize, convert, and propagate on an SPP surface. This will be a significant guidance on SPP nano-structure design and optimization.

In this study, we develop a two-step spin coating route without a template and use it to fabricate Cu2ZnSnS4 nanorods. Cu2ZnSnS4 nanorods with a diameter of about 30 nm were nearly perpendicular to the molybdenum-coated soda lime glass substrate. The results of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy confirm that the as-synthesized products are single-crystal/phase Cu2ZnSnS4 nanorods. The effects of various factors on the formation of Cu2ZnSnS4 nanorods are also investigated. Hall effect measurement reveals that the Cu2ZnSnS4 nanorod film has p-type conductivity.

There is extensive work developing laws that predict yielding in amorphous polymers, ranging from the pioneer experimental work of Sternstein et al (1968 Appl. Polym. Symp. 7 175–99) to the novel molecular dynamics simulations of Jaramillo et al (2012 Phys. Rev. B 85 024114). While atomistic models render damage criteria in terms of local values of the stress and strain fields, experiments provide yield conditions in terms of the average values of these fields. Unfortunately, it is not possible to compare these results due to the differences in time and length scales. Here, we use a micromechanical phase-field damage model with parameters calculated from atomistic simulations to connect atomistic and macroscopic scale experiments. The phase-field damage model is used to study failure in composite materials. We find that the yield criterion should be described in terms of local stress and strains fields and cannot be extended directly from applied stress field values to determine yield conditions.

The layered Li2MnO3 is investigated by using the first-principles calculations within the GGA and GGA+U scheme, respectively. Within the GGA+U approach, the calculated intercalation voltage (ranges from 4.5 V to 4.9 V) is found to be in good agreement with experiments. From the analysis of electronic structure, the pure phase Li2MnO3 is insulating, which is indicative of poor electronic-conduction properties. However, further studies of lithium ion diffusion in bulk Li2MnO3 show that unlike the two-dimensional diffusion pathways in rock salt structure layered cathode materials, lithium can diffuse in a three-dimensional pathway in Li2MnO3, with moderate lithium migration energy barrier ranges from 0.57 to 0.63 eV.

The memristor has broad application prospects in many fields, while in many cases, those fields require accurate impedance control. The nonlinear model is of great importance for realizing memristance control accurately, but the implementing complexity caused by iteration has limited the actual application of this model. Considering the approximate linear characteristics at the middle region of the memristance-charge (M—q) curve of the nonlinear model, this paper proposes a memristance controlling approach, which is achieved by linearizing the middle region of the M—q curve of the nonlinear memristor, and establishes the linear relationship between memristances M and input excitations so that it can realize impedance control precisely by only adjusting input signals briefly. First, it analyzes the feasibility for linearizing the middle part of the M—q curve of the memristor with a nonlinear model from the qualitative perspective. Then, the linearization equations of the middle region of the M—q curve is constructed by using the shift method, and under a sinusoidal excitation case, the analytical relation between the memristance M and the charge time t is derived through the Taylor series expansions. At last, the performance of the proposed approach is demonstrated, including the linearizing capability for the middle part of the M—q curve of the nonlinear model memristor, the controlling ability for memristance M, and the influence of input excitation on linearization errors.

Photo-induced intramolecular electron transfer (PIET) and intramolecular vibrational relaxation (IVR) dynamics of the excited state of rhodamine 6G (Rh6G+) in DMSO are investigated by multiplex transient grating. Two major components are resolved in the dynamics of Rh6G+. The first component, with a lifetime τPIET = 140 fs–260 fs, is attributed to PIET from the phenyl ring to the xanthene plane. The IVR process occurring in the range τIVR = 3.3 ps–5.2 ps is much slower than the first component. The PIET and IVR processes occurring in the excited state of Rh6G+ are quantitatively determined, and a better understanding of the relationship between these processes is obtained.

In this paper, the crossing point property of the i–v hysteresis curve in a memristor–capacitor (MC) circuit is analyzed. First, the ideal passive memristor on the crossing point property of i–v hysteresis curve is studied. Based on the analysis, the analytical derivation with respect to the crossing point location of MC circuit is given. Then the example of MC with linear memristance-versus-charge state map is demonstrated to discuss the drift property of cross-point location, caused by the frequency and capacitance value.