Chonbuk National University

About: Chonbuk National University is a education organization based out in Jeonju, South Korea. It is known for research contribution in the topics: Apoptosis & Graphene. The organization has 14820 authors who have published 28884 publications receiving 554131 citations.

Laccase immobilization on cellulose nanofiber: The catalytic efficiency and recyclic application for simulated dye effluent treatment

Abstract: In this study, laccase immobilized on cellulose nanofiber was utilized for reactive dyes and simulated dye effluent (SDE) decoloration. The thick coating on the fiber in the scanning electron microscopy (SEM) analysis and the N H stretching vibration between 1560 and 1640 cm−1 in the Fourier-transform infrared spectroscopy (FT-IR) spectra confirmed the laccase immobilization on nanofiber. The relative activity of the immobilized laccase was found to be 88%. The thermal and pH stability of the immobilized laccase was considerably improved. The best mediator for all of the reactive dyes that were tested and the SDE decoloration is 1-hydroxybenzotriazole (HBT). Response surface methodology (RSM) was used to improve the SDE decoloration. The half-life of the immobilized laccase was retained for up to 8 cycles and had greater than 85% SDE decoloration for up to 5 cycles. Therefore, laccase immobilized on cellulose nanofiber may be a good candidate for the textile effluent decoloration.

Sustainable Synthesis of Co@NC Core Shell Nanostructures from Metal Organic Frameworks via Mechanochemical Coordination Self-Assembly: An Efficient Electrocatalyst for Oxygen Reduction Reaction.

Abstract: Herein, a new type of cobalt encapsulated nitrogen-doped carbon (Co@NC) nanostructure employing Znx Co1-x (C3 H4 N2 ) metal-organic framework (MOF) as precursor is developed, by a simple, ecofriendly, solvent-free approach that utilizes a mechanochemical coordination self-assembly strategy. Possible evolution of Znx Co1-x (C3 H4 N2 ) MOF structures and their conversion to Co@NC nanostructures is established from an X-ray diffraction technique and transmission electron microscopy analysis, which reveal that MOF-derived Co@NC core-shell nanostructures are well ordered and highly crystalline in nature. Co@NC-MOF core-shell nanostructures show excellent catalytic activity for the oxygen reduction reaction (ORR), with onset potential of 0.97 V and half-wave potential of 0.88 V versus relative hydrogen electrode in alkaline electrolyte, and excellent durability with zero degradation after 5000 potential cycles; whereas under similar experimental conditions, the commonly utilized Pt/C electrocatalyst degrades. The Co@NC-MOF electrocatalyst also shows excellent tolerance to methanol, unlike the Pt/C electrocatalyst. X-ray photoelectron spectroscopy (XPS) analysis shows the presence of ORR active pyridinic-N and graphitic-N species, along with CoNx Cy and CoNx ORR active (M-N-C) sites. Enhanced electron transfer kinetics from nitrogen-doped carbon shell to core Co nanoparticles, the existence of M-N-C active sites, and protective NC shells are responsible for high ORR activity and durability of the Co@NC-MOF electrocatalyst.

Toward a Theory of Motivation and Personality with Application to Word-of-Mouth Communications

Abstract: Numerous scales have been developed to measure constructs relevant to consumer behavior, marketing, and management problems. Until recently, there has been no theory or model capable of providing an organizational structure for understanding the relationships among these numerous constructs. This paper presents the 3M Model of Motivation and Personality (Mowen 2000) as a viable theoretical approach for organizing constructs into an ordered nomological net. In addition, this effort illustrates how the 3M Model approach can be applied to personality research via an empirical study that investigates the trait antecedents of enduring dispositions to send and receive marketplace information across the U.S. and Korean cultures.

A novel method for making silica nanofibres by using electrospun fibres of polyvinylalcohol/silica composite as precursor

Abstract: For the first time, silica nanofibres with diameters of 200–400 nm were prepared by using electrospun fibres of polyvinylalcohol/silica composite as precursor. The products were characterized by the scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), and x-ray diffractometry (XRD) methods. The results showed that the crystalline phase and morphology of silica fibres were substantially influenced by the calcination temperature. The amorphous silica nanofibres could be obtained at 550oC.