INFLUENCE OF DOPING COMPONENT ON THE SOL-GEL PROCESS

Si-29 and Li-7 NMR have been used to study the sol-gel process. It has been found that the doping components (such as TlNO3, LiNO2, and Cd(NO3)(2)) could promote the hydrolysis and condensation reactions and their ratio, thus they could influence the gelation time. The lithium species has been demonstrated to remain as free hydration. ions during the whole sot-gel process and not to participate in forming the inorganic network.

Influence of Pressure on the Annealing Process of β-Ca_2SiO_4(C_2S) in Portland Cement

Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar, stucco, and non-speciality grout. Dicalcium silicate （Ca2SiO4） is the primary constituent of a number of different types of cement. The β-Ca2SiO4 phase is metastable at room temperature and will transform into β-Ca2SiO4 at 663K. In this work, Portland cement is annealed at a temperature of 950K under pressures in the range of 0-5.5 CPa. The high pressure experiments are carried out in an apparatus with six anvil tops. The effect of high pressure on the obtaining nano-size β-Ca2SiO4 （C2S） process is investigated by x-ray diffraction and transmission electron microscopy. Experimental results show that the grain size of the C2S decreases with the increase of pressure. The volume fraction of the C2S phase increases with the pressure as the pressure is below 3 CPa, and then decreases （P 〉 3 GPa）. The nano-effect is very important to the stabilization of β-Ca2SiO4. The mechanism for the effects of the high pressure on the annealing process of the Portland cement is also discussed.

Influence of substrate process tolerances on transmission characteristics of frequency-selective surface

Frequency-selective surface （FSS） is a two-dimensional periodic structure consisting of a dielectric substrate and the metal units （or apertures） arranged periodically on it. When manufacturing the substrate, its thickness and dielectric constant suffer process tolerances. This may induce the center frequency of the FSS to shift, and consequently influence its characteristics. In this paper, a bandpass FSS structure is designed. The units are the Jerusalem crosses arranged squarely. The mode-matching technique is used for simulation. The influence of the tolerances of the substrate＇s thickness and dielectric constant on the center frequency is analyzed. Results show that the tolerances of thickness and dielectric constant have different influences on the center frequency of the FSS. It is necessary to ensure the process tolerance of the dielectric constant in the design and manufacturing of the substrate in order to stabilize the center frequency.

Simultaneous Determination of Eleven Bioactive Constituents in Honey-Processed Licorice by High-Performance Liquid Chromatography-Diode Array Detector and Its Application from the Perspective of Processing Influence under Orthogonal Design

Objective:The aim of this study was to develop a reliable approach to simultaneously quantify 11 markers and explore the quality variation in honey-processed licorice.Materials and Methods:A high-performance liquid chromatography-diode array detector method was developed for the simultaneous determination of 11 markers(nine flavonoids and two triterpenoid saponins)in honey-processed licorice.The changes to the 11 markers in honey-processed licorice were investigated using an orthogonal design with three input factors.Results:The established method was precise,accurate,and sensitive enough for the simultaneous quantitative evaluation of 11 markers in honey-processed licorice.Intuitive analysis and variance analysis revealed that(1)the soaking time of crude licorice,stir-frying temperature,and stir-frying time remarkably influenced the content of liquiritin apioside,signifying the decomposition of liquiritin apioside to liquiritin or transformation of liquiritin apioside to isoliquiritin apioside,(2)stir-frying temperature significantly influenced licorice-saponin G2,(3)stir-frying temperature was the most important factor of the three input factors,(4)in terms of composition,honey fried licorice had significant effects on two components,namely liquiritin apioside and licorice-saponin G2.Conclusions:Honey processing influenced the content of the 11 licorice analytes differently.This paper highlights the first report on how the quality of honey-processed licorice varies under different processing conditions and suggests the optimal levels of the investigated three factors as A2B2C3 according to the degrees of influence of these factors on the 11 components.Specifically,the soaking time of crude licorice with honey solution,stir-frying temperature,and stir-frying time were 40 min,100°C,and 20 min,respectively.

INFLUENCES OF NONSTATIONARY PROCESS ON INTERNAL PARAMETERS AND WIND PROFILES IN THE PLANETARY BOUNDARY LAYER

In this paper,under the assumption of neutral and barotropic atmosphere,by means of the analytic solution of motion equation of PBL,the influences of nonstationary process on the internal parameters u_*/A(A is the wind speed at the top of PBL)and ■(the angle between winds near the surface and at the top of PBL)of PBL are investigated in which the wind direction at the top of PBL is a periodic function of time but the wind speed at the top of PBL does not change.The u_*/A increases and ■ decreases when the wind direction at the top of PBL rotates anticlockwise and vice versa.Hence the parameterization of PBL in the large-scale models derived under the stationary condition should be corrected by accounting for the nonstationary process.The similar results are obtained in the numerical solution of the motion equation of PBL.The influences of this nonstationary process on the profiles of the wind in PBL are also analyzed.