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.

Construction of imprint sites in mesopores of SBA-15 via thiol-ene click reaction

Abstract: This paper reports a new strategy for preparation of 2D molecularly imprinted materials (MIM) through the exploitation of thiol-ene click chemistry. 2D MIM for cholesterol was prepared using cholesterol as the template, acrolyl-modified β-cyclodextrin (acrolyl-β-CD) as the functional monomer, and thiol-modified SBA-15 (thiol-SBA-15) as the supporter. In this method, acrolyl-β-CD molecules were assembled around the templates by formation of template–monomer inclusion compounds. Then the acrolyl-β-CD molecules were anchored to the walls of the mesopores of SBA-15 via the thiol-ene click chemistry. After removal of the template molecules, the resulting recognition sites were formed in the mesopores of SBA-15. TEM, XRD, and N2 adsorption–desorption analysis results demonstrated that the synthesized MIM had a highly ordered mesoporous structure. Results from FT-IR revealed that acrolyl-β-CDs have been successfully conjugated to SBA-15. The density of β-CDs attached on the MIM is determined by EA and TGA. The equilibrium binding amounts of MIM and non-imprinted materials (NIM) for cholesterol are 53.50 and 25.24 μmol/g, respectively. The 2D MIM exhibited binding affinity and specificity for a group of analytes which have similar size and shape to those of template. The application of the prepared materials as stationary phases in thin layer chromatography was investigated preliminarily. The imprinted materials had higher retention ability for the template than the NIM. The retention factors (R f) of cholesterol on MIM and NIM are 0.62 and 0.81, respectively. The solid phase extraction of cholesterol using MIM as the adsorbent was further investigated. The recoveries of the molecularly imprinted solid phase extraction column for cholesterol were 77.1–94.7 % with relative standard deviations (RSD) of 2.25–6.78 %.

Regional coupled human-natural systems vulnerability and its evaluation indexes

Abstract: Unclear concept and scale positioning as well as imperfect evaluation system are the main obstacles of vulnerability evaluation.Starting from the concept,factor and scale of the coupled human-natural systems vulnerability,this article made it clear that the evaluation objective is in regional scale and the analysis framework is composed by climate change and system structural elements.Based on expounding the features of the coupled human-natural systems vulnerability,the authors established firstly an evaluation system of the coupled human-natural systems vulnerability,including the three series factor indexes of sensitivity,exposure and the adaptability,and three evaluation levels of background vulnerability,potential vulnerability and realistic vulnerability according to system relations of the three series factor indexes.Secondly,taking the hilly areas in southern China as an example,the authors established an evaluation index system of coupled human-environment interaction systems vulnerability in the erosion-prone region,which includes regional natural disasters such as debris flow,landslide,drought and flood,and which relies on the principles including the scientific principle,dominant factors principle,pertinence principle,applied principle and operability principle.Finally,the authors concluded that:(1) the regional coupled human-environment interaction systems vulnerability concerns with natural disasters under global climate change disturbance;(2) the sensitivity and damageability are the essential attribute of the vulnerability,while the sensitivity,exposure and adaptability are system factors of the vulnerability;(3) the natural disaster frequency can be seen as the location exposure indexes to reflect the space concentricity of disaster occurences,while the real disaster degree,as a reference value,can be provided to verify the results of the vulnerability evaluation indexes screening,index weights determinating,model validation and threshold value analysis.The research has some references for improving the theory and method of the research on regional coupled human-environment interaction systems vulnerability in different regions under the consistent framework.

Fluorogenic molecularly imprinted polymers with double recognition abilities synthesized via click chemistry

Abstract: This paper reports a new strategy for the preparation of molecularly imprinted polymer (MIP) based composite materials with double recognition abilities through the exploitation of click chemistry. Combining the inherent molecular recognition ability of MIPs and the affinity binding ability of boronic acid ligands for saccharides, a boronic acid-attached MIP with double recognition abilities was prepared. An alkyne modified 2,4-dichlorophenoxyacetic acid (2,4-D) imprinted polymer was first synthesized using a two-stage precipitation polymerization. An azide-contained boronic acid was then linked to the clickable 2,4-D imprinted polymers through copper-catalyzed azide–alkyne cycloaddition (CuAAC). The boronic acid-attached MIPs displayed recognition ability for 2,4-D and affinity binding ability for saccharides at physiological pH. The intensity of fluorescence emission of the boronic acid-attached MIPs was found to increase when increasing amounts of a cis-diol compound (i.e., fructose) were added.

Power Analysis Attack on a Lightweight Block Cipher GIFT

Abstract: GIFT is a new lightweight block cipher with smaller area and higher efficiency, which is very suitable for the Internet of Things (IoT) devices with constrained resources. The power analysis attack is an efficient method to extract the key from the cryptographic equipment. However, it is not easy to reveal the key by means of power analysis attack, when the cipher is implemented by hardware. In this article, we present the method of power analysis attack against GIFT. Firstly, we implemented GIFT on FPGA using the SAKURA-G board. Then, we explored the impact of point of interest (POI) on power analysis attack. We proposed the method of power analysis attack against the diffusion layer of GIFT. The experimental results show that the result of power analysis attack is affected by POI, and the key can be recovered when POI is registered. We can reveal the key using correlation power analysis, when targeting the diffusion layer of GIFT.