Fenghuang, China
Fenghuang, China

Longyan University is one of the full-time public undergraduate universities of Fujian Province authorized by the Ministry of Education of the People's Republic of China, which is located in Longyan City.The University occupies an area of 1058 mu, including Dongxiao campus and Fenghuang campus, with a total floor space of 230,000 square metres . Its library stores over 1,000,000 books and periodicals in Chinese and other languages, serving as the largest centre of information in west Fujian. Wikipedia.

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Yuan Q.-L.,Longyan University | Zhou X.-T.,Sun Yat Sen University | Ji H.-B.,Sun Yat Sen University
Catalysis Communications | Year: 2010

Highly efficient oxidative coupling of amines to imines by tert-butyl hydroperoxide (t-BuOOH) in the presence of metalloporphyrins has been reported. Manganese porphyrin showed excellent activity and selectivity for the oxidative coupling of amines to imines under ambient conditions. Moreover, a plausible mechanism involving high valence oxo intermediate has been proposed. © 2010 Elsevier B.V. All rights reserved.

Zhou X.-T.,Sun Yat Sen University | Yuan Q.-L.,Longyan University | Ji H.-B.,Sun Yat Sen University
Tetrahedron Letters | Year: 2010

Highly efficient oxidation of oximes to carbonyl compounds by molecular oxygen with benzaldehyde as an oxygen acceptor in the presence of metalloporphyrins has been reported. The simple structural manganese porphyrin showed an excellent activity for the oxidative deoximation reactions of various oximes. Moreover, different factors influencing oximes oxidation, that is, catalyst, solvent, and temperature, have been investigated. A possible mechanism for the deoximation reaction has been proposed. © 2009 Elsevier Ltd. All rights reserved.

Liu J.,East China Normal University | Liu J.,Longyan University | Ma S.,East China Normal University | Ma S.,CAS Shanghai Institute of Organic Chemistry
Organic Letters | Year: 2013

An aerobic oxidation of allylic alcohols using Fe(NO3) 3·9H2O/TEMPO/NaCl as catalysts under atmospheric pressure of oxygen at room temperature was developed. This eco-friendly and mild protocol provides a convenient pathway to the synthesis of stereodefined α,β-unsaturated enals or enones with the retention of the C-C double-bond configuration. © 2013 American Chemical Society.

Chen F.,Chongqing Three Gorges University | Wu S.,Longyan University
Scientific World Journal | Year: 2014

We establish some estimates of the right-hand side of Hermite-Hadamard type inequalities for functions whose derivatives absolute values are harmonically s-convex. Several Hermite-Hadamard type inequalities for products of two harmonically s-convex functions are also considered. © 2014 Feixiang Chen and Shanhe Wu.

Zeng W.,South China University of Technology | Zeng W.,Longyan University | Wang C.,South China University of Technology
Neural Networks | Year: 2012

Recognition of temporal/dynamical patterns is among the most difficult pattern recognition tasks. Human gait recognition is a typical difficulty in the area of dynamical pattern recognition. It classifies and identifies individuals by their time-varying gait signature data. Recently, a new dynamical pattern recognition method based on deterministic learning theory was presented, in which a time-varying dynamical pattern can be effectively represented in a time-invariant manner and can be rapidly recognized. In this paper, we present a new model-based approach for human gait recognition via the aforementioned method, specifically for recognizing people by gait. The approach consists of two phases: a training (learning) phase and a test (recognition) phase. In the training phase, side silhouette lower limb joint angles and angular velocities are selected as gait features. A five-link biped model for human gait locomotion is employed to demonstrate that functions containing joint angle and angular velocity state vectors characterize the gait system dynamics. Due to the quasi-periodic and symmetrical characteristics of human gait, the gait system dynamics can be simplified to be described by functions of joint angles and angular velocities of one side of the human body, thus the feature dimension is effectively reduced. Locally-accurate identification of the gait system dynamics is achieved by using radial basis function (RBF) neural networks (NNs) through deterministic learning. The obtained knowledge of the approximated gait system dynamics is stored in constant RBF networks. A gait signature is then derived from the extracted gait system dynamics along the phase portrait of joint angles versus angular velocities. A bank of estimators is constructed using constant RBF networks to represent the training gait patterns. In the test phase, by comparing the set of estimators with the test gait pattern, a set of recognition errors are generated, and the average L1 norms of the errors are taken as the similarity measure between the dynamics of the training gait patterns and the dynamics of the test gait pattern. Therefore, the test gait pattern similar to one of the training gait patterns can be rapidly recognized according to the smallest error principle. Finally, experiments are carried out on the NLPR and UCSD gait databases to demonstrate the effectiveness of the proposed approach. © 2012 Elsevier Ltd.

Here, the thermal stability of Ag(Al) films in air has been explored by the evolutions of surface morphology and optic-electric properties with annealing temperatures. The results show that the thermal stability of Ag films in air has been improved significantly by adding Al forming Ag(Al) films deposited on glass substrates by co-evaporation. In this experiment, optic-electric properties of Ag(Al) films are stable annealed between 400 and 600 °C for 1 h in air. Until the annealing temperature up to 700 °C, the slight agglomeration appeared in surface only results in the dramatic drop of surface reflectance. It is further found the evident concentration gradient of as-deposited film promotes mostly the distribution of Al gradually uniform and relays Ag agglomeration, meanwhile some Ag gently agglomerates in surface. After achieving a balance, the slight Ag agglomeration is formed in surface. © 2014 Elsevier B.V. All rights reserved.

Qiu L.-X.,Longyan University | Chen T.,Longyan University
World Journal of Gastroenterology | Year: 2015

Fatty liver disease (FLD) is a growing public health problem worldwide. There is an urgent requirement for alternative and natural medicine to treat this disease. As phytochemicals, isoflavones have attracted considerable attention for the prevention of FLD. Numerous studies have revealed that isoflavones protect against FLD through various pathways which modulate fatty acid β-oxidation, lipid synthesis, and oxidative stress. Recently, the aldose reductase (AR)/polyol pathway has been reported to be involved in the development of FLD by modulating hepatic fructose production, peroxisome proliferator-activated receptor (PPAR)α activity, cytochrome P450 (CYP)2E1 expression, and gut bacterial endotoxin-induced cytokine release. It has been reported that some isoflavones are potent AR inhibitors. Here, we review the anti-FLD actions of isoflavones and the proposed mechanism whereby isoflavones protect against FLD, with regard to the AR/polyol pathway. We propose that isoflavones block the AR/polyol pathway and in turn reduce fructose production and subsequent fat accumulation in the liver in diabetic or high-glucose-diet mice. In addition, in rodents with alcoholic liver disease or nonalcoholic fatty liver disease/nonalcoholic steatohepatitis, inhibition of AR by isoflavones may improve PPARα-mediated fatty acid oxidation, reduce hepatic steatosis, and attenuate CYP2E1-mediated oxidative stress or AR/gut bacterial endotoxin-mediated cytokine overproduction, to alleviate progression of FLD. © The Author(s) 2015.

A series of Ag films with different thicknesses were deposited on BK-7 glass, PET and PC substrates under identical conditions by thermal evaporation. The effect of the wettability on the morphology and optical properties of Ag/glass and Ag/polymer films was studied by atomic force microscopy and spectrophotometry. The experimental results show that the wettability of Ag grains with polymer is stronger than with glass, which results in the aggregation of bigger grains in initial layer. During deposition the interaction of interlayer plays an important role for the formation of the surface morphology. The strong wettability activates the nonlinear optical properties of Ag grains grown on polymer substrates, which result in the strong absorbance in short wavelength. The effect of the bare substrate on the transmittance of Ag films is more obvious than the reflectance. With the increasing of the thickness, the effect of the wettability on the morphology and optical properties of Ag films decline. In this experiment when the thickness is above 50 nm, the effect almost vanished. © 2013 Elsevier B.V. All rights reserved.

Zeng C.,Longyan University
AIP Conference Proceedings | Year: 2014

In this article, firstly, I will introduce the digital image compression and JPEG standards based on the DCT. In additional, the DCT simulation experiment through adopt MATLAB software. Next then, I will introduce the different methods of two-dimensional DCT (2-D DCT), including common 2-D DCT, fast 2-D DCT and matrix DCT. And two main techniques of fast 2-D DCT were emphasized, one method adopt common 1-D DCT algorithm and the other use 1-D FFT algorithm. Meanwhile, explain the block DCT method which adopt the above three DCT method. Furthermore, measure the characteristic of DCT and compare the above different DCT method. © 2014 AIP Publishing LLC.

Zhang L.,Longyan University
AIP Conference Proceedings | Year: 2014

The packet sets model was proposed by Prof. Shi in 2008. A packet sets is a set pair composed of internal and outer packet sets, and it has dynamic characteristic. Using packet sets theory, this paper gives the feature prediction of computer virus based on outer packet sets. The concept of virus screening-filtering is given, furthermore, the virus screening-filtering order theorem, composite virus screening-filtering theorem and virus screening-filtering rule are presented. A prediction method of computer virus feature is given based on the results. The outer packet sets is a new tool in the research of the prediction of dynamic virus feature. © 2014 AIP Publishing LLC.

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