[Raman, FTIR spectra and normal mode analysis of acetanilide].

The Raman and FTIR spectra of acetanilide (ACN) were measured experimentally in the regions of 3 500-50 and 3 500-600 cm(-1) respectively. The equilibrium geometry and vibration frequencies of ACN were calculated based on density functional theory (DFT) method (B3LYP/6-311G(d, p)). The results showed that the theoretical calculation of molecular structure parameters are in good agreement with previous report and better than the ones calculated based on 6-31G(d), and the calculated frequencies agree well with the experimental ones. Potential energy distribution of each frequency was worked out by normal mode analysis, and based on this, a detailed and accurate vibration frequency assignment of ACN was obtained.

[Study on the vibrational spectra of 3,5-dimethoxybenzyl alcohol].

3,5-dimethoxybenzyl alcohol (L1 OH) is a kind of important pharmaceutical intermediate and it is also the starting material of a family of dendrimer LnOH (integer n means the layers of "branch"). A number of articles reported the structure and properties of the L1 OH. However, its molecular vibrational spectra have not been reported up to date. Study of vibrational spectra on L1 OH at the molecular level can provide new information, which is significant for the in-depth study of related molecules of drug and the dendrimer. Recent studies indicated a morphology effect on the light-harvesting functions of dendritic macromolecules. In the present report, the Raman and FTIR spectra of 3,5-dimethoxybenzyl alcohol were measured experimentally. And the density functional theory (DFT) method (B3LYP/6-311G(d,p)) were used to calculate the equilibrium geometry and vibration frequencies of L1 OH. The results showed that the calculated frequencies agree well with the experimental ones. Potential energy distribution of each frequency was worked out by normal mode analysis. Thereafter the authors got a detail assignment of the vibrational frequencies for L1 OH for the first time. Also, the results showed that the DFT is really a useful method in the study of molecular vibrational spectra.

[Application of near infrared sensor to the technology of automobile transformation].

Using reflective near infrared sensor and voice record-reproducing assembly, the present article studies the voice anticollision-prompting device for backing an automobile. If there is a man or an object within a certain distance behind the backing automobile, part of the infrared signal will be reflected by the man or the object, and received by the photosensitive tube installed with a transmitting tube, and transformed to a similar frequency electric signal. The electric signal will be amplified, demodulated, and shaped by the circuit of module. After comparing and processing, the control signal will be output, which controls the work of voice record-reproducing assembly, and reminds the driver that there is a man or an object behind the backing automobile. With both the near infrared sensor and voice record-reproducing assembly being integrated, the distance-warning device has the advantages of low costs, simple wiring, strong anti-detonation ability, precise measuring, and working stability. It is suitable for being installed and used on the automobile.