Publications by authors named "Cheng-Ta Chang"

Isotopic compositions of B and Sr in rocks and sediments can be used as tracers for plant provincial sources. This study aims to test whether tea leaf origin can be discriminated using (10)B/(11)B and Sr isotopic composition data, along with concentrations of major/trace elements, in tea specimens collected from major plantation gardens in Taiwan. The tea leaves were digested by microwave and analyzed by multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS).

View Article and Find Full Text PDF

TiCl4-Mg can mediate addition of CHBr3 to a variety of aldehydes and ketones to form dibromomethyl carbinols and also be used to effect CBr3 transfer to carbonyl groups to form tribromomethyl carbinols. The successful application of TiCl4-Mg-promoted coupling of CHBr3 with various carbonyl compounds, especially in the case of highly enolizable ketones such as 2-indanone and β-tetralone, highlights the extraordinary reactivity and selectivity and the weakly basic nature of this system.

View Article and Find Full Text PDF

Background: Pulmonary tuberculosis (TB) is prevalent in Taiwan, but it is suspected that its occurrence has been underestimated by the National TB Surveillance Program. A pre-employment health examination is mandated by law in Taiwan, providing a mechanism to assess the occurrence of TB more accurately.

Methods: A pre-employment TB screening program of an industrial park was used to evaluate the performance of the National TB Surveillance Program in Taiwan.

View Article and Find Full Text PDF