Sol−Gel Derived Urea Cross-Linked Organically Modified Silicates. 1. Room Temperature Mid-Infrared Spectra

1999 ◽  
Vol 11 (3) ◽  
pp. 569-580 ◽  
Author(s):  
V. de Zea Bermudez ◽  
L. D. Carlos ◽  
L. Alcácer
Keyword(s):  
Infrared Spectra ◽  
Room Temperature ◽  
Sol Gel ◽  
Mid Infrared ◽  
Organically Modified Silicates ◽  
Organically Modified

Influence of Coumarin Dyes on the Laser Performance of Pyrromethene and Perylene Dyes Co-Doped into ORMOSILs

2007 ◽  
Vol 336-338 ◽  
pp. 574-576
Author(s):  
Hua Rong ◽  
Chun Fang Ye ◽  
Yu Yang ◽  
Guo Dong Qian ◽  
Zhi Yu Wang ◽  
...  
Keyword(s):  
Sol Gel ◽  
Laser Wavelength ◽  
Laser Dyes ◽  
Co Doping ◽  
Organically Modified Silicates ◽  
Sol Gel Process ◽  
Organically Modified ◽  
Transfer Mechanisms ◽  
Co Doped ◽  
Coumarin Dyes

Laser dyes perylene red (p-red) or pyrromethene 567 (p567) were co-doped with coumarin 440 (C440) or coumarin 500 (C500) into MTES- and VTES-derived organically modified silicates (ORMOSILs) by sol-gel process. The effects of coumarin dye concentration on the laser performances of p-red and p567 were investigated. The results from laser efficiency measurements illustrated that at optimized coumarin concentration, the slope efficiency of co-doped p-red increased by a factor of 2 while that of co-doped p567 increased marginally. It was also found that by co-doping coumarin, the laser wavelength of p-red blue shifted and the laser thresholds for p567 and p-red could be reduced. The energy transfer mechanisms involved were also discussed.

Infrared spectra of the natural zeolite heulandite

1985 ◽  
Vol 50 (10) ◽  
pp. 2134-2138 ◽  
Author(s):  
František Pechar
Keyword(s):  
Absorption Spectra ◽  
Raman Spectra ◽  
Infrared Spectra ◽  
Natural Zeolite ◽  
Room Temperature ◽  
Far Infrared ◽  
Reflection Spectra ◽  
Mid Infrared

The mid-infrared (4 000-200 cm-1) absorption spectra, far infrared (400-40 cm-1) absorption spectra, infrared (1 400-200 cm-1) reflection spectra, and Raman spectra (3 600-50 cm-1) were measured at room temperature for polycrystalline heulandite, a natural zeolite from Poonah, India.

Sol−Gel Derived Urea Cross-Linked Organically Modified Silicates. 2. Blue-Light Emission

1999 ◽  
Vol 11 (3) ◽  
pp. 581-588 ◽  
Author(s):  
L. D. Carlos ◽  
V. de Zea Bermudez ◽  
R. A. Sá Ferreira ◽  
L. Marques ◽  
M. Assunção
Keyword(s):  
Blue Light ◽  
Light Emission ◽  
Sol Gel ◽  
Blue Light Emission ◽  
Organically Modified Silicates ◽  
Organically Modified

Transmission infrared study of acid-catalyzed sol-gel silica coatings during room ambient drying

1992 ◽  
Vol 7 (8) ◽  
pp. 2230-2239 ◽  
Author(s):  
T.M. Parrill
Keyword(s):  
Thin Films ◽  
Fourier Transform ◽  
Infrared Spectra ◽  
Spin Coating ◽  
Room Temperature ◽  
Sol Gel ◽  
Infrared Study ◽  
Silica Coatings ◽  
Acidic Conditions ◽  
Acid Catalyzed

Sol-gel solutions prepared from tetraethylorthosilicate (TEOS) hydrolyzed in acidic conditions were used to make thin films on Si wafers via spin coating. Solutions with H2O/TEOS ratios of 2, 5, and 10 were prepared and aged at room temperature in sealed containers for times ranging from <2.5 h to 1 month. Transmission Fourier transform infrared spectra acquired around 1 min after spinning showed peaks characteristic of both SiO2 and SiOH. Additional features at ≍580, 1093, and 1130 cm−1 were observed and possible origins are discussed. Peaks at ≍580 and 1130 cm−1, which increased in intensity with solution age time, are attributed to cyclic Si–O, e.g., 4-member rings. When films were exposed to room air, ring concentration decreased significantly within 30 min. Rings were stable for hours, however, when films were kept in N2. The feature at 1093 cm−1, most sensitive to H2O/TEOS, is attributed to residual Si–O–C.

scholarly journals Organically Modified Silicates by the Sol-Gel Process

1984 ◽  
Vol 32 ◽  
Author(s):  
H. Schmidt
Keyword(s):  
Sol Gel ◽  
New Materials ◽  
Organic Components ◽  
Organically Modified Silicates ◽  
Sol Gel Process ◽  
Inorganic As ◽  
Organically Modified ◽  
General Aspects

ABSTRACTThe introduction of organic groups into inorganic networks by the sol-gel process opens the possibility for the preparation of new materials, and typical properties resulting from inorganic as well as from organic components may be combined. Some general aspects and different examples of material developments are reviewed.

Molecular Design of Organically-Modified ‘Smart’ Sol-Gel Materials

2002 ◽  
Vol 726 ◽  
Author(s):  
Mukti S. Rao ◽  
Bakul C. Dave
Keyword(s):  
Smart Materials ◽  
Structural Changes ◽  
Molecular Design ◽  
Molecular Level ◽  
Sol Gel ◽  
Stimuli Responsive ◽  
Design Synthesis ◽  
Organically Modified Silicates ◽  
Organically Modified ◽  
Responsive Behavior

AbstractThe design, synthesis and stimuli-responsive behavior of organically-modified silicates (ORMOSILS) is reported. The ORMOSILS behave as ‘smart’ materials by undergoing structural changes at the molecular level to respond to changes in environmental variables. Typical responses in the form of swelling/shrinkage with respect to changes in temperature, pH, and salt concentrations are presented. Finally, the nature of predominant mechanism responsible for the sol-gel's behavior towards combined stimuli of high temperature and low pH is discussed.

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