Capital Normal University

About: Capital Normal University is a education organization based out in Beijing, China. It is known for research contribution in the topics: Terahertz radiation & Quantum entanglement. The organization has 11441 authors who have published 11988 publications receiving 159071 citations. The organization is also known as: Shǒudū Shīfàn Dàxué.

Colorimetric Sensor Array for Discrimination of Heavy Metal Ions in Aqueous Solution Based on Three Kinds of Thiols as Receptors

Abstract: In the present work, we report a novel colorimetric sensor array for rapid identification of heavy metal ions. The sensing mechanism is based on the competition between thiols and urease for binding with the metal ions. Due to the different metal ion-binding abilities between the thiols and urea, different percentages of urease are free of metal ions and become catalytically active in the presence of varied metal ions. The metal ion-free urease catalyzes the decomposition of urea releasing ammonia and changing the pH of the analyte solution. Bromothymol blue, the pH indicator, changes its color in response to the metal-caused pH change. Three different thiols (l-glutathione reduced, l-cysteine, and 2-mercaptoethanol) were used in our sensor array, leading to a unique colormetric repsonse pattern for each metal. Linear discriminant analysis (LDA) was employed to analyze the patterns and generate a clustering map for identifying 11 species of metal ions (Ni2+, Mn2+, Zn2+, Ag+, Cd2+, Fe3+, Hg2+, Cu2+, Sn4+, ...

Using an online collaborative project between American and Chinese students to develop ESL teaching skills, cross-cultural awareness and language skills

Abstract: The purpose of this study was to explore the potential of computer-mediated communication (CMC) tools to facilitate second language acquisition and develop English as a second language (ESL) teaching skills and cultural awareness. The paper describes a collaborative online project between students from China and the USA. who communicated using the discussion board and e-mail tools on blackboard for tutoring and learning different aspects of English grammar and for developing culture awareness. Twenty-three American students from an ESL teaching program were paired up with 26 Chinese first-year English majors and tutored them on grammar structures that they selected after analyzing the Chinese students’ introductory essays on American life and culture for grammar mistakes. The tutorials addressed specific grammar points and were presented through texts that described different aspects of American culture. The Chinese students used the discussion board and e-mail as well as Skype to communicate with their A...