In this paper, we demonstrate the high power diode-side-pumped Nd:YAG laser on the low gain three lines at 1112, 1116 and 1123 nm. By special coating design or inserting etalon in the cavity, the single wavelength oscillation can be achieved with high output power either in continuous-wave (CW) mode or in actively Q-switched (QS) mode. With special coating design, the maximum CW output power at 1123 nm can be up to 219.3 W. By tuning the tilt angle of an etalon in the cavity, the highest output powers at 1112, 1116 and 1123 nm were obtained to be 72, 43 and 63 W operated in QS mode, and 75, 47 and 71W in CW mode, respectively. This compact laser system, which is capable of selectively operation at one of the three lines at 1112, 1116 and 1123 nm, is of important practical value. The high power achievable with the present laser may enable some interesting applications, such as chemistry, differential absorption lidar, second harmonic generation (SHG) into visible and fourth harmonic generation (FHG) into ultraviolet lasers.
The original and deconvoluted spectra of Attenuated Total Reflection (ATR) FTIR have been determined for both benign and malignant tumor tissues samples and the spectral differences have been investigated between the two types of samples. In comparison with the benign samples, the characteristic changes of malignant ones mainly involve: The prominent bands 1652 and 1645cm<sup>-1</sup> due to the proteins in the α-helical and the unordered-random-coils substructures become stronger compared to those in the β-sheet and the turns substructures, suggesting that the former type of proteins increase in content in contrast to the later. The phospodiester band 1083 cm<sup>-1</sup> of the nucleic acids becomes strongest on cancer tissues spectra and its area ratio to the amide II band 1548cm<sup>-1</sup> rises greatly, indicating that the DNA content rises remarkably. The collagen proteins reduce in content while phosphorylated ones rise, and some hydrogen bonding is nearly broken in amino acid residue C-O (H) groups. The glycogen content decreases, and the CH<sub>2</sub> content is higher than CH<sub>3</sub> one. These results suggest that ATR-FTIR spectroscopy has the potential to become a powerful tool for biochemical studies and in vivo diagnosis of human breast cancers.