Hengyang Normal University

About: Hengyang Normal University is a education organization based out in Hengyang, China. It is known for research contribution in the topics: Graphene & Adsorption. The organization has 1087 authors who have published 1280 publications receiving 13850 citations. The organization is also known as: Hengyang Teachers' College & Héngyáng Shīfàn Xuéyuàn.

A Split-Complex Valued Gradient-Based Descent Neuro-Fuzzy Algorithm for TS System and Its Convergence

Abstract: In order to broaden the study of the most popular and general Takagi–Sugeno (TS) system, we propose a complex-valued neuro-fuzzy inference system which realises the zero-order TS system in the complex-valued network architecture and develop it. In the complex domain, boundedness and analyticity cannot be achieved together. The splitting strategy is given by computing the gradients of the real-valued error function with respect to the real and the imaginary parts of the weight parameters independently. Specifically, this system has four layers: in the Gaussian layer, the L-dimensional complex-valued input features are mapped to a Q-dimensional real-valued space, and in the output layer, complex-valued weights are employed to project it back to the complex domain. Hence, split-complex valued gradients of the real-valued error function are obtained, forming the split-complex valued neuro-fuzzy (split-CVNF) learning algorithm based on gradient descent. Another contribution of this paper is that the deterministic convergence of the split-CVNF algorithm is analysed. It is proved that the error function is monotone during the training iteration process, and the sum of gradient norms tends to zero. By adding a moderate condition, the weight sequence itself is also proved to be convergent.

3D-Construction of Vasculature of Anaxagorea and its Implications in the Integrated Axial-Foliar Origin of the Angiosperm Carpel

Abstract: How flowers have evolved is among the foremost topics in evolutionary science. However, previous studies can only explain in general how angiosperm flowers originated as a whole. The origin of flowers involves the evolution of key characters of floral organs. Therefore, investigating the origin of the particular component parts of the flower can bring us more clues to the origin of angiosperms. Carpel is the basic unit of the gynoecium in angiosperms, and it is also one of the most important morphological features of angiosperms different from gymnosperms. Therefore, the origin of carpels is of great significance to the phylogenetic origin of angiosperms. Conflicting theories with regard to flower origins have provided varied explanations. According to the traditional explanations, angiosperm carpels emerged from structures similar to macrosporophylls of pteridosperms or Bennettitales, which bear ovules on the surface of foliar organs. Conversely, other views based on the stachyosporous origin theory suggest that the carpel originates from foliar appendages enclosing the ovule-bearing axis in gymnosperms. Since it has been confirmed by morphological and molecular evidences that the carpel wall is certainly derived from foliar homologs, if the axial homologs in the carpel are determined, the carpel would more likely be derived from an ovule-bearing axis fused with the leaf-like structure than from the megasporophyll. The aim of this study is to trace the axial homologous in the carpel by analyzing the continuous changes of vascular diagrams in the receptacle, carpel and ovule in Anaxagorea. Anaxagorea is the most basal genus of primitive angiosperms Annonaceae. Each carpel in Anaxagorea has a notable long carpel stipe, which is one of the key characteristics of the genus. In this paper, floral organogenesis of A. luzonensis and A. javanica were described. The topological structure of vasculature in the receptacle and the carpel in different development stages were studied. And the 3D model of vascular diagrams of mature carpel of A. javanica was established. The results show that: (1) at flower stage, discrete vascular bundles (far more than three) entering carpel stipe of Anaxagorea, which were arranged as a ring, similar to the arrangement of vascular bundles in stems. All of these carpel bundles are originated from the central stele in the receptacle. (2) Below each of the placenta, the ring-arranged bundles at the base of carpel were reorganized into two groups of lateral bundle complexes, and in each group of lateral bundle complex, bundles are also arranged as a ring. (3) In each group of the lateral bundle complex, some non-adjacent bundles get close to each other through the topological secondary ring, and finally merged with each other into the ovule bundle. (4) Neither the dorsal bundle nor the ventral bundle is involved in formatting of the ovule bundles, and there is no connection between the ovule bundles and bundles in the ovary wall. These results support the stachyosporous origin theory that the carpel originates from the integration of the ovular axis and the foliar appendage, and provide a valuable trait for the molecular mechanism of carpel origin.

Syntheses, crystal structures and luminescent properties of Ag(I) complexes with benzilic carboxylate and 2,6-pyridinedicarboxylate

Abstract: Two complexes [Ag(bpy)(H2O)]·(Hbac) (1) and [Ag2(bpy)2(H2O)2](pdc)·(H2O)5 (2) (H2bac = benzilic acid, bpy = 4,4′-bypyridine, H2pdc = 2,6-pyridinedicarboxylic acid) have been synthesized and characterized by IR, element analysis, X-ray-single crystal diffraction and TGA. Crystal data for 1: Monoclinic, space group C2/c, a = 18.8192(5) A, b = 12.7131(5) A, c = 17.8373(8) A, β = 95.745(4)°, V = 4246.1(3) A3 and Z = 8; 2: Triclinic, space group, P-1, a = 8.132(5) A, b = 10.485(6) A, c = 18.026(10) A, α = 96.194(10)°, β = 91.047(11)°, γ = 105.866(10)°, V = 1468.0(15) A3 and Z = 2. In complex 1, Ag(I) is coordinated by two discrete 4,4′-bpy ligands and one water molecule and Hbac− behaves as a counterpart anion. In the crystal, a 3D network was formed by hydrogen bonds and π–π face-to-face interactions. In complex 2, Ag(I) is also coordinated by two discrete 4,4′-bpy ligands and one water molecule and pdc2− behaves as a counterpart anion, too. In the crystal, a similar 3D network was formed by hydrogen ...

Trace determination of zirconium by adsorptive anodic stripping voltammetry of its complex with alizarin violet using a glassy carbon electrode modified with acetylene black-dihexadecyl hydrogen phosphate composite film

Abstract: We report on a novel electrochemical method for the sensitive determination of trace zirconium (Zr) at a glassy carbon electrode modified with a film of acetylene black containing dihexadecyl hydrogen phosphate and in the presence of alizarin violet (AV). The method is based on the preconcentration of the Zr(IV)-AV complex at a potential of −200 mV (vs. SCE). The adsorbed complex is then oxidized, producing a response with a peak potential of 526 mV. Compared to the poor electrochemical signal at the unmodified GCE, the electrochemical response of Zr(IV)-AV complex is greatly improved, as confirmed by the significant increase in peak current. The effects of experimental conditions on the oxidation current were studied and a calibration plot established. The oxidation current is linearly related to the Zr(IV) concentration in the 8.0 pM to 10 nM concentration range (cAV = 0.2 μM) and 10 nM ~0.6 μM (cAV = 2.0 μM), and the detection limit (S/N = 3) is as low as 4.0 pM for a 3-min accumulation time. The method was successfully employed to the determination of zirconium in standard ore samples.