Time filter

Source Type

Zhao Y.,Lingnan Normal University
Journal of Computational and Theoretical Nanoscience | Year: 2017

Physical education teaching in colleges and universities is a complicated project for systematic optimization with multiple factors. As a vital approach to enhance the quality of physical education teaching in colleges and universities, it is of great importance to have a scientific, accurate and objective evaluation of physical education teaching. The thesis, on the one hand, analyzes the existent problems during the evaluation course of physical education teaching in colleges and universities; and on the other hand, discusses the related improved measures on the aforementioned basis. In order to update the evaluation index system of physical education teaching in colleges and universities, the thesis, based on the multiple intelligence theory, constructs an evaluation index system of physical education from all-round aspects, i.e., teaching step, teaching and learning step as well as managing step. Furthermore, according to the weight of various evaluation indexes on the foundation of AHP method, plus with the involvement of fuzzy evaluation information, the thesis puts forward with a comprehensive fuzzy evaluation model of physical education teaching in colleges and universities. This model serves as an attempt to effectively evaluate physical education teaching, the validity of which is proved in the case analysis part. Copyright © 2017 American Scientific Publishers.

Deng S.,Lingnan Normal University | Sun S.-M.,Virginia Polytechnic Institute and State University
Nonlinearity | Year: 2017

The paper considers the stationary Swift-Hohenberg equation cw-(∂x 2+k0 2)2w-w3=0, where c > 0 is a constant, , and is a small parameter. In this case, the linear operator has a pair of real eigenvalues and a pair of purely imaginary eigenvalues. It can be proved that the equation has homoclinic (or single hump) solutions approaching to periodic solutions as (called single-hump generalized homoclinic solutions). This paper provides the first rigorous proof of existence of homoclinic solutions with two humps which tend to periodic solutions at infinity (or two-hump generalized homoclinic solutions) by pasting two appropriate single-hump generalized homoclinic solutions together. The dynamical system approach is used to reformulate the problem into a classical dynamical system problem and then the solution is decomposed into a decaying part and an oscillatory part at positive infinity. By adjusting some free constants and modifying the single-hump generalized homoclinic solution near negative infinity, it is shown that the solution is reversible with respect to a point near negative infinity. Therefore, the translational invariant and reversibility properties of the system yield a two-hump generalized homoclinic solution. The method may be applied to prove the existence of 2k-hump solutions for any positive integer k. © 2017 IOP Publishing Ltd & London Mathematical Society.

Mo J.-X.,Lingnan Normal University | Li G.-Q.,Lingnan Normal University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

In this paper, we investigate the coexistence curves and molecule number densities of f(R) anti-de Sitter (AdS) black holes and Gauss-Bonnet AdS black holes. Specifically, we work with the reduced parameter space and derive the analytic expressions of the universal coexistence curves that are independent of theory parameters. Moreover, we obtain the explicit expressions of the physical quantity describing the difference of the number densities of black hole molecules between the small and large black holes. It is found that both the coexistence curve and the difference of the molecule number densities of f(R) AdS black holes coincide with those of Reissner-Nordström-AdS black holes. It may be attributed to the same equation of state they share in the reduced parameter space. The difference of the molecule number densities between the small and large Gauss-Bonnet AdS black holes exhibit different behavior. This may be attributed to the fact that the charge of the Reissner-Nordström-AdS black hole is nontrivial. Our research will not only deepen the understanding of both the physics along the coexistence curve and the underlying microscopic freedom of AdS black holes but also highlight the importance of the law of the corresponding states. © 2015 American Physical Society.

Miao W.,Lingnan Normal University | Qin L.,CAS Beijing National Laboratory for Molecular | Yang D.,CAS Beijing National Laboratory for Molecular | Jin X.,CAS Beijing National Laboratory for Molecular | Liu M.,CAS Beijing National Laboratory for Molecular
Chemistry - A European Journal | Year: 2015

A new class of L-glutamic gelators, LG12(CH2)nCOOH, containing different lengths of methylene spacer were synthesized. It was found that the gelation ability of these compounds themselves was very weak. However, when another compound, p-xylylenediamine (XEA), was introduced, the gelation ability was improved greatly. In particular, LG12(CH2)10COOH showed super-gelation ability in the presence of XEA, which could immobilize almost all of the solvents except methanol. Moreover, the formed supramolecular gels even could be molded. Interestingly, some supramolecular gels of LG12(CH2)nCOOH and XEA could respond to multiple stimuli, such as heating, shaking, sonication, and acid/base. The studies of CD spectra suggested that the supramolecular chirality induced by self-assembled chiral gelator molecules in gels could be tuned by the length of methylene spacer. In addition, the supramolecular chirality could be regulated as on/off by heating-cooling or external NH3/HCl. This would facilitate the development of dual chiroptical switches by temperature and acid/base. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA.

Miao W.,Lingnan Normal University | Yang D.,CAS Beijing National Laboratory for Molecular | Liu M.,CAS Beijing National Laboratory for Molecular
Chemistry - A European Journal | Year: 2015

Abstract A new class of homologous gelators, LG12-(CH2)n-BSA, composed of bipyridinyl groups, L-glutamic moieties having double dodecyl chains, and linked alkyl spacers with different lengths were synthesized. It was found that these gelators could immobilize medium-polarity solvents readily and the behaviors of these gels showed a dependence on the spacer length. Of all the gels, the LG12-(CH2)11-BSA gels exhibited self-healing property and multiple-stimulus responsibility, such as heating, shaking, and sonication. The investigation of CD spectra indicated that the supramolecular chirality, which was attributed to the chiral transfer from the chiral center to the assemblies, was also closely related to the length of methylene spacers. The longer the alkyl spacers, the weaker the transmitted supramolecular chirality. Only LG12-(CH2)1-BSA gelators, which had the shortest spacers, formed right-handed nanoscale chiral twists owing to crowded hydrogen bonding interactions. Moreover, the high-polarity solvent DMF was found to be able to regulate the chiral twist as well as its pitch length readily. A new twist on healing: Self-healing supramolecular gels that are responsive to multiple stimuli were developed. The formation of nanoscale twists could be controlled by the length of the methylene spacers of the gelator molecules. The pitch of these twists could be regulated by DMF. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Wang Y.,Lingnan Normal University
Journal of Physical Organic Chemistry | Year: 2016

The reaction of N,N-dimethylaniline with tetrachloromethane in ionic liquid was found to give 4,4′-methylene-bis (N,N-dimethylaniline) in considerable yield. The ionic liquid was prepared from N,N-dimethylaniline which is also the one of raw materials for the preparation of 4,4′-methylene-bis (N,N-dimethylaniline), and acts as both solvent and catalyst in the reaction. Mild reaction conditions, enhanced rates, improved yields, and reagents' reactivity which is different from that in conventional organic solvents are the remarkable features observed in ionic liquids. In addition, the results of calculations are in good accordance with the experimental outcomes. © 2016 John Wiley & Sons, Ltd.

Mo J.-X.,Lingnan Normal University
Modern Physics Letters A | Year: 2015

The thermodynamic geometry of black holes with conformal anomaly has been investigated in this paper. We study two classical kinds of thermodynamic geometry. Namely, Weinhold geometry and Ruppeiner geometry. It is shown that the condition when Weinhold scalar curvature diverges is the same as the phase transition condition characterized by the divergence of specific heat. It is also shown that Ruppeiner scalar curvature not only reveals the phase structure but also contains the information of Hawking temperature. In a word, both Weinhold metric and Ruppeiner metric can correctly reproduce the phase structure of black holes even when conformal anomaly is taken into consideration. © 2015 World Scientific Publishing Company.

Yang X.-Y.,Lingnan Normal University
Transactions of Nonferrous Metals Society of China (English Edition) | Year: 2015

The molecular dynamics (MD) simulation and the modified analytical embedded-atom method (MAEAM) were used to study the influence of a He atom on the movement of the edge dislocation in Ni. First, the calculated Burgers vector distribution shows that the equilibrium dissociation distance (Ded) and the stacking fault energy (Esf) between two partial edge dislocations are about 25.95 Å and 108 mJ/m2, respectively. Then, the obtained formation energies (Ef) of a He atom at some different sites demonstrate that the He atom is attracted and repelled in the tension and compression regions, respectively. And the He-dislocation interaction reveals that an interstitial He atom plays a more significant role in the dislocation movement than a substitutional He atom. Finally, it is found that the movement of an interstitial He atom is apparent as the first partial dislocation bypasses and the edge dislocation offers fast-diffusion path for the migration of a He atom. © 2015 The Nonferrous Metals Society of China.

The objective of this study was to extract the oil from Camellia oleifera seeds by aqueous enzymatic oil extraction (AEOE). A novel process for extraction of oil using industrial enzymes from microwave puffing-pretreated Camellia oleifera seed powder was described. The results indicated that the free oil extraction efficiency obtained with microwave-assisted extraction was very high, which the recovery yield was up to 55% (dry weight of Camellia oleifera seed). Besides, microwave pretreatment of Camellia oleifera seed increased the tocopherols (by 22.2% -39.4%), squalene(by 6.3% -29.2%) and phytosterols (by 6.7% -14.8%) of the oils extracted by AEOE. Moreover, a very low acid value and peroxide value of oil superior to those of oils obtained by previous works was obtained. From the obtained results, this novel process may prove to be an environment-friendly alternative to solvent extraction. Copyright © 2016, Japanese Society for Food Science and Technology.

Zhen C.,Lingnan Normal University
Journal of Computational and Theoretical Nanoscience | Year: 2016

Wisdom port is the future development trend of port. In order to effectively construct wisdom port, the relationship between the port logistics and the information industry of the city need to be studied. In this paper, a System Dynamics model of wisdom port-city coupling is established based on the system characteristics, boundary and the causal relationship of its elements. Then take Shenzhen as the empirical research object, select the appropriate control variables to analyze the interaction of various elements in the process of simulating. The results show that the development of the information technology industry is closely linked with the port city. Only investing into the port facilities is not an obvious way to improve the port handling capacity. But the port and logistics industry would shift to high value-added trend by information technology in-depth excavating of port business potential. Copyright © 2016 American Scientific Publishers. All rights reserved.

Loading Lingnan Normal University collaborators
Loading Lingnan Normal University collaborators