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  • Author: Lijun Wang x
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Abstract

According to the analysis from the number of tourists who went to Lanzhou during 2009–2019, the ARIMA model of the number of tourists to Lanzhou was established. The results show that the AR(3) model is used to predict the number of tourists who traveled to Lanzhou during 2009–2019. The average relative error between the predicted value and the actual value is 1.03%, which can be used to predict and analyze the number of tourists in Lanzhou in the future.

Abstract

In this paper, the inviscid limit behavior of solution of the fractional complex Ginzburg–Landau (FCGL) equation

tu+(a+iν)Λ2αu+(b+iμ)u2σu=0,(x,t)Tn×(0,)
is considered. It is shown that the solution of the FCGL equation converges to the solution of nonlinear fractional complex Schrödinger equation, while the initial data u0 is taken in L2, Hα, and L2σ+2 as a,b tends to zero, and the convergence rate is also obtained.

Abstract

In this work, the rolling process was employed to fabricate polylactic acid/multi-walled carbon nanotube (PLA/MWCNT) composites at room temperature. The effects of the rolling conditions on the mechanical and electrical properties of the fabricated composites were investigated. The evolution processes of the internal molecular structures, i.e. changes in molecular orientation and crystallinity, were examined by X-ray diffraction, differential scanning calorimetry, and density method. The results suggested that the molecular orientation improved; however, the crystallinity decreased when the rolling ratio increased. The analysis of the mechanical properties revealed that the rolled composites displayed anisotropy during the rolling process. In the rolling direction, after adding 1 wt.% MWCNTs, the tensile strength increased from 58.6 to 94.3 MPa with the rolling ratio, whereas the fracture strain sharply increased to 131.5% at the rolling ratio of 60%. In addition to the mechanical properties, electrical resistivity was also investigated; notably, this property was not significantly affected by the rolling process. Furthermore, the MWCNT dispersion and morphology were investigated by scanning electron microscopy. These findings offer a simple and effective method to fabricate conductive composites with excellent mechanical properties.

Abstract

Standard partial molar volumes V 2,Φ 0, viscosity B-coefficients and molar conductivities λm for the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate [C4mim][PF6] in aqueous ethanol solutions (x ethanol = 0.5∼0.9) have been determined from density, viscosity and conductivity measurements at 298.15 K. It is shown that values of V 2,Φ 0 decrease, while those of viscosity B-coefficients increase with increasing mole fraction of ethanol in the solvents. The molar conductivities of the ionic liquid are found to be decreased with increase of both the ionic liquid concentration and the ethanol content in the systems. Experimental results have been discussed in terms of the ionic liquid–solvent interactions and the ion associations of the ionic liquid in aqueous ethanol solutions.

Abstract

With the country to the advancement of “the Belt and Road Initiatives” strategy of Xinjiang is positioned as a national strategic energy base, the development of renewable energy is an important part in the development of energy industry in Xinjiang and occupy the important status of wind power, to the Xinjiang economy and play an important role in promoting the development of clean energy. This paper introduces the development status quo of wind power industry in Xinjiang, analyzed under the background of “the Belt and Road Initiatives”, the development of wind power industry is facing opportunities and challenges in Xinjiang, and in view of the current challenges, and the solution is given.

Abstract

The aim of the present study was to investigate the alterations of the physiological properties associated with the ultrastructure changes of rice seed after drying at different temperatures. The drying process was accomplished at 30, 45, 60, 75 and 90°C and at 29.3%, 13.0%, 6.4%, 3.2%, and 1.8% relative humidity, respectively. As a result, the germination percentage of the rice seeds was reduced as the increasing of the drying temperature and the highest value of vigor index was recorded at 45°C due to the dormancy breakage. There were no changes in the color of the raw rice seed dried at different temperatures; however, the yellowness of the brown rice and the electrical conductivity increased with the increasing drying temperature. The starch granules of the rice endosperm dried at 45°C were wrinkled and wilted and this damage occurred with high intensity after drying at temperatures above 60°C. The structure of the starch granules eventually became rupture when the drying temperature reached to 90°C. The cells of the rice embryo presented a contraction of their volumes drying at temperatures above 45°C due to the degradation of the middle lamella. The form of the oil drops was also altered after drying. At temperature above 75°C, the drops broke up and coalesced. It was concluded that the physiological quality of rice seed was closely associated with the alterations of cell structure during drying process.

Abstract

Electrical conductivity of molten slags is one of the most important physicochemical properties and it also has a close relationship to the structure of slag. This article focused on the basic slag system CaO-MgO-Al2O3-SiO2 and made estimations for electrical conductivity. Ion-oxygen parameter was selected to describe the relationship between electrical conductivity with compositions. Moreover, the interaction between composition and temperature was embodied in the final model formula. It was shown that increasing CaO and MgO contents enhanced the ability for electric conduction. Moreover, with a higher temperature, the change of electrical conductivity with ion-oxygen parameter was more remarkable. This model gives reasonable prediction of the electrical conductivity for the slags studied with the mean deviation of 14.3%. Thus, this model would provide a feasible tool for industry to predict and optimize the electrical conductivity of slag system.