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Flavones were extracted from Physalis alkekengi L. coating by ultrasonic method. Effects of material ratio, concentration of alcohol, ultrasonic time, temperature and power on the yield of flavones were studied. Optimal extracting conditions were determined through single factor and orthogonal experiments. The results showed that when ultrasonic power was 450 W, ratio of material to liquid was 1:50, the optimal extracting conditions were as follows: concentration of alcohol 50%, ultrasonic time 20 min, ultrasonic temperature 80°C, under above conditions, extraction yield of flavones was 1.93%. which approximated the predicted value of 2.05%.

The model R5912-20MOD photomultiplier tube(PMT) is made for cryogenic application by Hamamatsu. In this paper, we report on the measurement of relative quantum efficiency (QE) of this model PMT at liquid argon(LAr) temperature. Furthermore, a specially designed setup and relevant test method are introduced. The relative QE is measured in visible wavelengths with the PMT emerged in high purity nitrogen atmosphere. The results show that the change of QE at LAr temperature is within about 5% compared with room temperature around 420 nm. However, the QE increases about 10% in the shorter wavelength range and decreases significantly after 550 nm., 10 pages, 6 figures

In this paper, potato peel were used as raw material. Taking water-insoluble dietary fiber as index, the effects of acid-alkali extraction time, concentration of acid extraction and alkali extraction on water-insoluble dietary fiber in potato peel were investigated by acid-base chemical method. The optimum process conditions for extracting dietary fiber were determined by neutral detergent method. The results showed that the yield of water insoluble dietary fiber could reach 12.6% when the acid-alkali extraction time was 35 minutes, the acid extraction concentration was 1.5%, the alkali extraction concentration was 1.6%.

Three-dimensional nanocrystalline models of LiAlO2 with the log-normal grain size distribution are constructed with constrained Voronoi tessellation. First, the relaxation procedure of nanostructured LiAlO2 is carried out using molecular dynamics. The results suggest a reduction in the atomic densities after the relaxation process. Next, the tensile deformation and fracture behavior of nanostructured LiAlO2 are studied by using the optimized model. By researching the tensile deformation and fracture behavior of nanostructured LiAlO2 , we find some interesting results: on the one hand, the greater the average grain size of the sample is, the stronger its tensile strength. On the other hand, after the strain reaches approximately 3% of the deformation of the sample, the stress of the sample does not change with the increase of the strain, displaying a plastic flow of the plastic material.

Short-time dynamic behaviour of two-dimensional fully frustrated XY model near the Ising-like phase-transition temperature is studied with resistively shunted junction dynamics. The transition temperature Tc and the dynamic and static critical exponents z, 2β/ν and ν are estimated under both a periodic boundary condition (PBC) and a fluctuating twist boundary condition (FTBC) using the short-time dynamic scaling analysis. The results show that Tc, 2β/ν and ν are almost independent of the boundary conditions, whereas z depends on the boundary condition. The value of z = 2.18(5) of the PBC is roughly equal to that of the FFXY model with Monte Carlo dynamics under the PBC, while z = 2.05(4) of the FTBC is in agreement with that of the Coulomb gas model.

The templated-rGO fabric, featuring high conductivity (

An ab initio calculations on the ground and low-lying excited states (X2Σ+, 22Σ+, 32Σ+, 14Π, 24Π, 14Σ+, 24Σ+, and 34Σ+) of KBe molecule have been performed using multireference configuration interaction (MRCI) plus Davidson corrections (MRCI+Q) approach with all electron basis set aug-cc-pCV5Z-DK for Be and def2-AQZVPP-JKFI for K. The 32Σ+, 14Π, 24Π, 14Σ+, 24Σ+, and 34Σ+ states are investigated for the first time. Inner shell electron correlations are computed on the potential energy curves (PECs) calculations. The spectroscopic and molecular parameters are also predicted. In addition, The transition properties including transition dipole moment, Franck–Condon factors qυ'υ'' , Einstein coefficients Aυ'υ'' , and the radiative lifetimes τυ' for the , , and transitions are predicted at the same time.

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.

We perform a first-principles study of the mechanical and vibrational properties of ZnS with a wurtzite structure. The calculated elastic constants by using a pseudopotential plane-wave method agree well with the experimental data and with the previous theoretical works. Based on the elastic constants and their related parameters, the crystal mechanical stability is discussed. Calculations of the zone-center optical-mode frequencies including longitudinal-optical/transverse-optical splitting, by using the density functional perturbation theory, are reported. All optical modes are identified, especially B1 modes, and agree with Raman measurements.

In this paper, in order to solve the interface-trap issue and enhance the transconductance induced by high-k dielectric in metal—insulator—semiconductor (MIS) high electron mobility transistors (HEMTs), we demonstrate better performances of recessed-gate Al2O3 MIS-HEMTs which are fabricated by Fluorine-based Si3N4 etching and chlorine-based AlGaN etching with three etching times (15 s, 17 s and 19 s). The gate leakage current of MIS-HEMT is about three orders of magnitude lower than that of AlGaN/GaN HEMT. Through the recessed-gate etching, the transconductance increases effectively. When the recessed-gate depth is 1.02 nm, the best interface performance with τit = (0.20−1.59) μs and Dit = (0.55−1.08) × 1012 cm−2 eV−1 can be obtained. After chlorine-based etching, the interface trap density reduces considerably without generating any new type of trap. The accumulated chlorine ions and the N vacancies in the AlGaN surface caused by the plasma etching can degrade the breakdown and the high frequency performances of devices. By comparing the characteristics of recessed-gate MIS-HEMTs with different etching times, it is found that a low power chlorine-based plasma etching for a short time (15 s in this paper) can enhance the performances of MIS-HEMTs effectively.

Homogeneous monolith of A1PO4 gel doped with rhodamine 6G (Rh6G) at different dye loadings is prepared by a one-step process with sol-gel method using the precursors A1(lact)3 and H3PO4. The optical properties of A1PO4 gel doped with Rh6G are characterized by UV-Visible absorption spectra and fluorescence spectra. Rh6G molecular J-dimers and H-dimers even multimers are analyzed by excitation spectra based on exciton theory. The A1PO4 gel doped with Rh6G dye with molar ratio of Rh6G/A1(lact)3 of 1 × 10−4 has excellent optical properties without obvious aggregates.

This paper performs the two-dimensional, soft-sphere molecular dynamics simulations to study the granular segregation in a binary granular mixture with the same size but different density in the container with the sawtooth base under horizontal vibration. The segregation phase diagram is presented in the acceleration-frequency space. When the acceleration is high enough to result in relative motions of the particles, the system can be in various states (mixed state, vertical and horizontal segregation state), which depend on both acceleration and frequency. Due to the sawtooth base there is stratified flow effect besides density effect. The density effect raises the light particles. The stratified flow drives the particles in the upper levels to the right and the particles in the lower particles to the left, resulting in the appearance of the left segregation state. The left segregation state can be changed to the right segregation by changing the shape of the sawtooth. As the vibration frequency increases, the stratified flow effect becomes weaker and weaker, so at high vibration frequencies the vertical segregation state appears instead of the left segregation state.