The fragmentation pathway of the ions, [M-15 (CH3)] + and [M-15-90 (TMSOH)] +, of 0-trimethylsilyl (TMS) derivatives of long chain base detected by gas chromatography combined with electron-impact mass spectrometry were studied by molecular orbital calculation (AM1). The calculation results showed that the [M-15] + cyclic ion was produced by the loss of one methyl radical from the TMS group of C-1 and then the [M-15-90] +ion was produced by the loss of the TMSOH from the [M-15] +ion. Elucidation of the structure of the m/z 132 ion ([H2NCHCH2OTMS] +) was also carried out using molecular orbital calculation (AM1).
MOLDA for Windows, an interactive personal-computer molecular modeling and molecular graphics program, which can be used as an interface to the ab initio molecular orbital program GAUSSIAN 94, the molecular dynamics simulation program AMBER 4.0 and the molecular mechanics program MM2, is described. The molecular model constructed by using MOLDA can be transferred to the Virtual Reality Modeling Language (VRML) format file and viewed by using a VRML viewer on the World Wide Web (WWW).
CyberMol, an interactive molecular graphics program system on the World Wide Web (WWW) using the Common Gateway Interface (CGI) is presented. The molecular coordinates which are inputted from the WWW browser can be transferred to the Virtual Reality Modeling Language (VRML) format file and viewed as a molecular model by using a VRML viewer on the WWW. The vibrational modes calculated by the ab initio molecular orbital program GAUSSIAN 94 can be visualized. The organic molecular structure database and the search engine for displaying molecular models by using the VRML viewer are also provided.
An experimental system was designed to support students for self-paced and self-directed curriculumn learning. It is a client-server system based on WWW combined with newsand mail systems. It is able to deal with multimedia teaching materials like text data and image data. An open corner for questions and answers and a private communication route are provided through a browser nterface in order to provide an interaction between students and teachers. An auto-examination system to test the student's accomplishment is also included. The use situation by the student can always be monitored by the teacher. For the student, the educational system has the advantage that any part of the course can be learned at anytime without restriction by a time-table. The system is suitable for a preliminary or a supplementary course for student who are short of basic academic ability.