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The low-temperature nonequilibrium characteristics of dielectric barrier discharge (DBD) make it an important candidate for the decomposition and conversion of CO2. In this study, quartz, alumina and zirconia are selected as the dielectrics to investigate the effect of dielectric materials of planar DBD reactor on the discharge and conversion characteristics of CO2. It is shown that under the same input power conditions, zirconia has the highest CO2 conversion rate when used as a dielectric, followed by alumina, and quartz has the lowest. Combined with the analysis of the measured electrical characteristics, it is shown that zirconia has the highest transferred charge, thus further increasing the discharge efficiency. Experimental results of the single dielectric barrier layer-metal mesh electrode reactor show that the CO2 discharge can operate in the lower power range and the CO2 conversion rate is higher than that of the double dielectric barrier layer reactor. Spectroscopic measurements show that the emission intensity of the discharge in the reactor with high relative permittivity materials is higher than that in the case of low relative permittivity materials, and the emission intensity of the single dielectric layer reactor is also higher than that in the case of the double dielectric layer reactor.

The preparation of surface-enhanced fluorescence (SEF) substrates is often influenced by experimental strategies and factors such as the morphology and size of the nanostructures. In this study, using the natural reed leaves (RLs) without any special pretreatment as the substrate, metal silver is modified by magnetron sputtering technology to prepare a stable and efficient SEF system. The abundant “hedgehog-like” protrusions on the RL substrate surface can generate high-density “hot spots”, thus enhancement factor (EF) is enhanced up to 3345 times. The stability and reproducibility are verified in many measurements. The contribution of the intervention of silver nanostructure to the radiation attenuation process of fluorescent molecules is analyzed with the aid of Jablonski diagrams. Three-dimensional (3D) finite difference time domain (FDTD) simulates the spatial electric field and “hot spots” distribution of the substrate. The “hedgehog-like” protrusion structure generates multiple “hot spots”, which produce an excellent local surface plasmon resonance (LSPR) effect and provide higher fluorescence signal. Finally, RL/Ag-35 substrate is used to detect crystal violet (CV), and the detection limit is as low as 10−13 M. This “hedgehog-like” SEF substrate provides a new strategy for the trace detection of CV, which has a good practical application value.

The article illustrates basic operations and control features of ABS system. To Control the ABS Slip Ratio with Simulink, and create a single wheel ABS model according to the ABS principle. It produces Simulation curves, which verifies that the Auto ABS has good braking performance and direction of the manipulation.

In this paper, the dynamic performance of turbocharged diesel engine is studied comprehensively and systematically by using a high altitude diesel engine simulation test-bed to simulate different altitudes. The influence of altitude change on the dynamic performance of turbocharged diesel engine is analyzed, which provides an important basis for further improving and enhancing the performance of turbocharged diesel engine at high altitude.

A new composite electrochemistry-dual circuit polarization model (E-DCP) is proposed by combining the advantages of various electrochemical empirical models in this paper. Then, the multi-innovation least squares (MILS) algorithm is used to perform online full parameter identification for the E-DCP model in order to improve data usage efficiency and parameter identification accuracy. In addition, on the basis of the E-DCP model, the MILS and the extended Kalman filter (EKF) are combined to enhance the state estimation accuracy of the battery management system (BMS). Finally, the model and the algorithm are both verified through urban dynamometer driving schedule (UDDS) and the complex charge-discharge loop test. The results indicate that the accuracy of E-DCP is relatively high under different working conditions, and the errors of state of charge (SOC) estimation after the combination of MILS and EKF are all within 2.2%. This lays a concrete foundation for practical use of the BMS in the future.

Zero-energy renovation is carried out on the envelope structures and renewable energy systems of the reference buildings, and control function was constructed with the energy-saving quantities in the total life cycle of the renovated and pre-renovation buildings, which was optimized and solved using the NSGAII (Non-dominated Sorting Genetic Algorithm II) to obtain the optimal renovation scheme. The entropy weight evaluation is employed to evaluate the optimal scheme. The reference buildings are subjected to energy-saving renovation according to the optimal method, and the relationship between energy supply and energy consumption is analyzed for each reference building in each month. This study offers a method for the optimization and evaluation of zero-energy consumption in residential buildings, which provides guidance for the zero-energy residential building renovation.

Most engineered rough surfaces approximately follow non-Gaussian distributions, which plays an important role in Vehicle gears lubrication performance in contract area. A three-dimensional elastohydrodynamic lubrication (EHL) model for involute Vehicle gears is developed by making the contact between surfaces during meshing tooth surfaces equivalent to an infinite line-contact model. By using the proposed model and non-Gaussian random roughness surfaces of given parametersgenerated by numerical simulation method based on FFT, the meshing process of spur and helical Vehicle gears is analyzed. The film thickness, contact area ratio and contact load ratio of contacting points of vehicle gears with different surface roughness characteristics are obtained as well.

The vehicle compressor impeller of the turbocharger of the vehicle is often damaged by the vibration. Model analysis for the compressor impeller is a kind of common means to avoid resonance between the impeller and natural frequency. Based on the software of ANSYS, the mid and low order nature frequency of vehicle compressor impellerwas simulated and calculated by the method of submodel, and Campbell chart was drawn according to the results. The resonance speed of the nature frequency of compressor impeller was found, thus reference for optimal design of the compressor impeller was provided.

In recent years, the 3D fluorescence excitation emission spectrum has been widely applied into the analysis of the properties of soluble organic matter in water bodies, but there is very little research on the fluorescence properties of protein residues in water quality detection by Fluorescence Excitation Emission Matrix (FEEM), and synchronous fluorescence excitation emission spectra (SFS). The characteristics of luminescent of amino acids, including tryptophan, tyrosine and phenylalanine, where tryptophan and tyrosine fluorescence are relatively strongest, and the effects of tyrosine on the fluorescence properties of tryptophan are seldom discussed in different mixing ratios for both amino acids. The fluorescent peak positions and intensities of the three amino acids are related to the angle size of conjugate plane, N hybrids and hydroxyls on benzene rings. When the ratio of tyrosine to tryptophan content is less than 150:100, tryptophan will quench the fluorescent peak of the tyrosine. Constant tryptophan content, tyrosine at excitation wavelength of 228 nm, its concentration changes with the corresponding fluorescence intensity has a good linear relationship; however, at 276-278 nm of tyrosine, the varied concentrations and fluorescence intensities are opposite.

Based on first-principles density functional theory, we investigated the relationship between the vibrational normal modes and the spectrum of the newest laboratory-prepared ice phase, an empty clathrate hydrate structure from gas hydrate named ice XVII. A 48-molecule supercell was designed to mimic the hydrogen-disordered structure. Despite its much lower density than ice Ih, its phonon density of states shows features very similar to those of that phase. In our previous studies of ice Ic and ice XIV, we found two basic hydrogen bond vibrational modes in these hydrogen-ordered ice phases, which contribute two sharp hydrogen bond peaks in the translation region. In this study, we found that this rule also holds in the hydrogen-disordered phase ice XVII. A water molecule vibrating along its angle bisector possesses strong energy, because this vibrational mode involves oscillation against four bonded neighbors. In contrast, a water molecule vibrating perpendicular to its angle bisector has low energy because this mode involves only two of the molecule’s hydrogen bonds. This is an evidence in hydrogen-disordered ice and strengthens our proposal that the existence of two basic hydrogen bond vibrational modes is a general rule among ice family.

The Veselov's discrete Neumann system is derived through nonlinearization of a discrete spectral problem. Based on the commutative relation between the Lax matrix and the Darboux matrix with finite genus potentials, a special solution is calculated with the help of the Baker—Akhiezer—Kriechever function.

The electrical property of thin-layer black phosphorus (BP) was explored using a simple dry transfer method, which greatly reduced the fabrication time to carry out electrical measurement starting from an initial state with little degradation. As a result, the as-prepared BP field-effect transistor (FET) exhibited a high on/off ratio exceeding 104 and a high hole mobility of 380 cm2/(V·s). The time-dependent electrical property of BP indicated a declining and recovering process, caused by the degradation and doping effect. Finally, it was demonstrated that the degradation and large hysteresis of BP FET could be modified by covering a thin Al2O3 layer.

Linear alkyl benzene (LAB) will be used as the solvent of a liquid scintillator mixture for the JUNO antineutrino experiment in the near future. Its light absorption property should therefore be understood prior to its effective use in the experiment. Attenuation length measurements at a light wavelength of 430 nm have been performed on samples of LAB prepared for the purpose of the JUNO experiment. Inorganic impurities in LAB have also been studied for their possibilities of light absorption in our wavelength of interest. In view of a tentative plan by the JUNO collaboration to utilize neutron capture with hydrogen in the detector, we have also presented in this work, a study on the carbon-hydrogen ratio and the relationship thereof with the attenuation length of the samples.

A highly sensitive sensor with piezoresistive nanocomposite material assembled in a flexible composite film is designed and tested for hydrodynamic sensing. Within the device, two nanocomposite films with micrometer scale modified small bumps on the surface are arranged together face-to-face by the interlocking mechanism. These structures are verified to have full-scale piezoresistive high sensitivities which are very appropriate for underwater sensing. Obvious output signals can be observed from the device subjected to the hydroacoustic dipole (vibrating sphere) with exciting frequency from 10Hz to 40Hz. A spectral peak can be seen in the Fourier analysis of the output signal at the corresponding frequency.

Fluctuations of cathode cavity pressure and arc voltage are observed experimentally in a dc plasma torch with a long inter-electrode channel. The results show that they have the same frequency of around 4 kHz under typical experimental conditions. The observed phase difference between the pressure and the voltage, which is influenced by the path length between the pressure sensor and the cathode cavity, varies with different input powers. Combined with numerical simulation, the position of the pressure perturbation origin is estimated, and the results show that it is located at 0.01-0.05m upstream of the inter-electrode channel outlet.

The entropic stochastic resonance (ESR) in a confined system subjected to dichotomous noise and white noise and driven by a periodic sinusoidal force along the x axis of the structure and a time-dependent force in the declining direction, is investigated. Under the adiabatic approximation condition and based on the two-state theory, the expression of the output signal-to-noise ratio (SNR) is obtained. The results show that the SNR is a non-monotonic function of the strengths of dichotomous noise, white noise, and correlated strength of correlated noise. In addition, the SNR varies non-monotonically with the increase of the shape parameters of the confined structure, and also with the increase of the constant force along the y axis of the structure. The influence of the correlation rate of the dichotomous noise, and that of the frequency of the periodic force on the SNR are discussed.

A method is developed to construct discrete Lax pairs using Darboux transformations. More kinds of Lax pairs are found for some newly appeared discrete integrable equations, including the H1, the special H3 and the Q1 models in the Adler—Bobenko—Suris list and the closely related discrete and semi-discrete pKdV, pMKdV, SG and Liouville equations.

Acoustic holography has attained a high lateral resolution but a poor axial resolution. In this study, to achieve the high axial resolution, time slice is applied to an imaging system using acoustic holography. The time slice can select the reflected signals from objects at different distances. In this method, the sampling interval of detected signal decides the axial resolution, and the aperture of the transducer decides the lateral resolution. The result of a simulation shows good axial and lateral resolutions. The method uses only one specified frequency which matches with narrow-band transducers.