An infrared spectroscopic study of the reactions of silicic acid with heavy metal ions

This paper deals with the results of an infrared spectroscopic study of the reactions of low polymeric silicic acid with heavy metal ions. The individuality of the compounds obtained is established. It is also found that the shift in the IR absorption band of the Sio ₄ ^4– tetahedra depends on the number and kinds of cations taking part in the reaction. Conclusions are drawn concerning the reaction mechanism. The thermal transitions of the compounds synthesized have been studied.     

An infrared spectroscopic study of the structural phase transitions of n-C10H21NH3Cl

Infrared spectroscopy was used to study the phases of n-decylammonium chloride in the temperature range 20 to 65°C. The infrared spectra of virgin crystals at room temperature are indicative of a well-ordered phase, while the spectra of the high temperature phase demonstrate extensive motional and conformational disorder. The phase obtained by cooling from 65 to 25°C also presents motional and conformational disorder. However, it is metastable and annealing for 13 days at room temperature (25°C) results in a phase similar but not identical to the virgin crystals.     

In situ infrared spectroscopic study of cubicboron nitride thin film delamination

This paper investigates the procedure of cubic boron nitride （cBN） thin film delamination by Fourier-transform infrared （IR） spectroscopy. It finds that the apparent IR absorption peak area near 1380cm^-1 and 1073 cm^-1 attributed to the B-N stretching vibration of sp2-bonded BN and the transverse optical phonon of cBN, respectively, increased up to 195% and 175% of the original peak area after film delamination induced compressive stress relaxation. The increase of IR absorption of sp2-bonded BN is found to be non-linear and hysteretic to film delamination, which suggests that the relaxation of the turbostratic BN （tBN） layer from the compressed condition is also hysteretic to film delamination. Moreover, cross-sectional transmission electron microscopic observations revealed that cBN film delamination is possible from near the aBN（amorphous BN）/tBN interface at least for films prepared by plasma-enhanced chemical vapour deposition.     

Phase transformation of natural titanite: An infrared,Raman spectroscopic,optical birefringence and X-ray diffraction study

The thermal behaviour of natural titanite has been studied using infrared and Raman spectroscopy, linear birefringence and synchrotron X-ray diffraction. Natural single crystals from Rauris, Austria (Fe 1.8%. Al 3.8%) were investigated and two additional samples from the Smithonian Institute Washington (Fe 2.8%, Al 0.5% and Fe 8.8%, Al 13.9%) served for IR and birefringence measurements. The coupled substitution of Fe and Al for Ti and OH and F for O leads to the formation of long ranging defect fields which are assumed to account for an increased density of antiphase boundaries. Infrared absorption spectra show increased bandwidths with increasing defect concentration. The phase transition near 500 K is clearly seen in the IR spectra of samples with low defect concentrations but not for those with high defect densities. X-ray diffraction shows strong anisotropic diffuse scattering in the Rauris sample leading to the average symmetry A2/a at room-temperature. A second anomaly at ca. 850 K was found by X-ray diffraction techniques using synchrotron radiation and by a break in the temperature evolution of the IR spectra.     

Growth kinetics of self-assembled monolayers of thiophene and terthiophene on Au(111): An infrared spectroscopic study

The growth kinetics of self-assembled monolayers (SAMs) of thiophene compounds on Au(111) surfaces was revealed by Fourier-transform infrared reflection absorption spectroscopy (FT-IR-RAS). Thiophene and terthiophene form well-ordered SAMs on Au(111) surfaces by immersing gold substrates into their ethanol solutions for ca. 15 h. Gibbs free energies for the adsorption processes of thiophene and terthiophene were found to be identical. However, the growth and molecular orientation of SAMs are different between two thiophene compounds. Terthiophene in SAMs orients parallel to the surface. The SAM growth of terthiophene obeys a time-dependent Langmuir scheme. On the other hand, the thiophene SAM undergoes a two-step growth process with unique molecular orientations. In the primary phase, thiophene assumes a parallel orientation on the Au(111) surface. In the second phase, thiophene is oriented close to the normal of the surface. The different growth process between thiophene and terthiophene is attributable to the topology of sulfur positions in the molecules. Received 23 May 2001 and Received in final form 11 February 2002     

EVOH树脂薄膜制备及其保温性能的红外光谱研究

采用平挤上吹成膜工艺制备了EVOH,PE,EVA薄膜,并利用红外光谱仪、透光率/雾度测定仪等分别研究了以EVOH,PE,EVA树脂为基材生产的薄膜的透光率、雾度、红外阻隔率和温室增温、保温性能的关系.结果表明在光学性能上,EVOH树脂薄膜比常用的PE和EVA农膜的雾度分别下降10%和5%左右;从红外透射率来看,EVOH...     

Contribution of near infrared laser techniques to the spectroscopic study of black liquids

We present here what we believe to be an original investigation of oil products optical properties (refractive index, fluorescence emission, isotropic and anisotropic Rayleigh scattering) using c.w and Q-switched laser waves in the near infrared (1064 nm). The results obtained show that IR laser techniques can elegantly solve the problem of optical measurements in black liquids and solids.