Raman Spectroscopic Studies of the Vulcanization of Rubbers. II. Raman Spectroscopic Studies as a Function of Cure Time

1971 ◽  
Vol 44 (4) ◽  
pp. 904-913 ◽  
Author(s):  
J. R. Shelton ◽  
J. L. Koenig ◽  
M. M. Coleman
Keyword(s):  
Raman Spectroscopy ◽  
Raman Line ◽  
Spectroscopic Studies ◽  
Conjugated Dienes ◽  
The Other ◽  
Asymptotic Dependence ◽  
Raman Spectroscopic ◽  
Cure Time ◽  
Conjugated Triene ◽  
Vulcanization Process

Abstract It has been demonstrated that Raman spectroscopy can be used to follow changes that occur in the network of vulcanizates as a function of cure time. In the system studied we have found that dialkenyl sulfides, cyclic sulfides and conjugated triene structures parallel the cure. In other words, the Raman lines due to these structures display an asymptotic trend as a function of cure time with the plateau occurring in the region of the optimum cure time. On the other hand those Raman lines assigned to the trans isomer and conjugated dienes do not exhibit the same asymptotic dependence as a function of cure time but show an increase in intensity as the cure time is prolonged up to at least 2 hours at 150° C. This would appear to indicate that these Raman lines are not solely associated with the vulcanization process but that thermal and allied processes may contribute. The Raman line occurring at 440 cm−1 does not show any definitive trend and is unlikely to be associated directly with the network. It is most probably due to unextracted extra-network ZnO present.

A Furnace for Molten Salt Raman Spectroscopy to 800°C

1971 ◽  
Vol 25 (1) ◽  
pp. 82-84 ◽  
Author(s):  
Arvin S. Quist
Keyword(s):  
Raman Spectroscopy ◽  
Laser Beam ◽  
Molten Salts ◽  
Spectroscopic Studies ◽  
Sample Container ◽  
Raman Spectroscopic ◽  
Laser Raman ◽  
Different Types ◽  
Sample Chamber ◽  
Metal Block

A vacuum tight furnace has been constructed and used for laser-Raman spectroscopic studies of molten salts to 800°C. The sample container is positioned within the furnace by a removable metal block, several designs of which have been used with different types of sample containers. The sample under investigation is easily and rapidly aligned in the laser beam by means of micrometer screws located on the positioning table which supports the furnace. The compactness of the entire unit allows it to be readily moved into and out of the sample chamber of the spectrometer.

scholarly journals Cryogenic Raman Spectroscopic Studies on Common Ore-forming Fluid Systems

Minerals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 363
Author(s):  
Dan Yang ◽  
Xin Xiong ◽  
Weishi Chen
Keyword(s):  
Raman Spectroscopy ◽  
Quantitative Analysis ◽  
Correlation Coefficient ◽  
Fluid Inclusions ◽  
Intensity Ratio ◽  
Spectroscopic Studies ◽  
Ore Deposits ◽  
Raman Spectroscopic ◽  
Freezing Method ◽  
Fluid Systems

The composition and properties of ore-forming fluids are key to understanding the mechanisms of mineralization in ore deposits. These characteristics can be understood by studying fluid inclusions. Hydrates in fluid inclusions containing NaCl–H2O and MgCl2–H2O were studied using cryogenic Raman spectroscopy. The intensity ratio of peaks at 3401, 3464, 3514, and 3090 cm−1 shows a positive correlation with the concentration of hydrates in the inclusions, as does the ratio of the total integrated area of the MgCl2 hydrate peak (3514 cm−1) to the 3090 cm−1 peak with the concentration of MgCl2 (correlation coefficient >0.90). These correlations are important in the quantitative analysis of MgCl2 in synthetic and natural NaCl–MgCl2–CaCl2–H2O-bearing fluid inclusions. Semi-quantitative analysis of NaCl–MgCl2–H2O solutions indicates that peaks at 3437 and 3537 cm−1 reflect the presence of NaCl in the solution. Further, a peak at 3514 cm−1 is indicative of the presence of MgCl2. The relative intensities of these peaks may be related to the relative abundances of NaCl and MgCl2. A quantitative attempt was made on NaCl–MgCl2–CaCl2–H2O system, but it was found that quantifying NaCl, MgCl2 and CaCl2 separately in NaCl–MgCl2–CaCl2–H2O system by the secondary freezing method is difficult.

Raman Spectroscopic Studies of the Vulcanization of Rubbers. III. Studies of Vulcanization Systems Based on 2-Mercaptobenzothiazole

1972 ◽  
Vol 45 (1) ◽  
pp. 173-181 ◽  
Author(s):  
M. M. Coleman ◽  
J. R. Shelton ◽  
J. L. Koenig
Keyword(s):  
Raman Spectra ◽  
Raman Line ◽  
Lauric Acid ◽  
Spectroscopic Studies ◽  
Type I ◽  
Raman Spectroscopic ◽  
Major Significance ◽  
Sulfur Vulcanization ◽  
Cyclic Sulfide

Abstract The shoulder observed at approximately 440 cm−1 in Raman spectra of CB vulcanizates prepared from MBT based vulcanizing systems has been shown to consist of two components. There are Raman lines contributing at 440 cm−1 and 424 cm−1. The former is due to ZnO present as an extra-network material while the latter appears to be associated with polysulfidic structures. The Raman line at 505 cm−1 seen in extracted vulcanizates prepared from CB-MBT-Sulfur-ZnO-Lauric acid recipes does not appear to be solely due to disulfidic structures. The major contribution appears to be associated with an unsaturated cyclic sulfide and is most probably due to a structure of the type (I). If the assignment to cyclic sulfidic structures such as (I) is confirmed, it will have major significance with regard to the mechanism of accelerated sulfur vulcanization.

Raman Spectroscopic Studies of Amsacrine

1992 ◽  
Vol 46 (10) ◽  
pp. 1540-1544 ◽  
Author(s):  
Catherine A. Butler ◽  
Ralph P. Cooney ◽  
William A. Denny
Keyword(s):  
Crystal Structure ◽  
Raman Spectroscopy ◽  
Crystal Structure Data ◽  
Visible Spectrum ◽  
Spectroscopic Studies ◽  
Resonance Raman Spectrum ◽  
Raman Spectroscopic ◽  
Ft Raman Spectroscopy ◽  
Uv Visible ◽  
Ft Raman

Amsacrine (4′-(9-acridinylamino)methanesulfon- m-anisidide) in both solid and aqueous forms was characterized with the use of resonance and nonresonance Raman spectroscopy (including FT-Raman spectroscopy). Evidence that the acridine nucleus is the dominant chromophoric unit contributing to the resonance Raman spectrum is based upon the apparent similarities of the spectra of aqueous amsacrine (in the unpro-tonated form) and acridine (in ethanol). The probable non-coplanarity of the acridine and phenyl units in the amsacrine molecule (based on previously reported crystal structure data) is consistent with the suggestion that the acridine nucleus may constitute an independent chromophoric unit. Further evidence is derived from analysis of the UV-visible spectrum, which indicates that excitation at 457.9 nm falls within an electronic transition of the acridine nucleus of amsacrine. The excitation profiles of aqueous amsacrine are presented, and four types of profiles have been identified.

scholarly journals Operando Raman spectroscopic studies of lithium zirconates during CO2 capture at high temperature

RSC Advances ◽  
2016 ◽  
Vol 6 (10) ◽  
pp. 8222-8231 ◽  
Author(s):  
Diana Peltzer ◽  
John Múnera ◽  
Laura Cornaglia
Keyword(s):  
Raman Spectroscopy ◽  
High Temperature ◽  
Co2 Capture ◽  
Phase Evolution ◽  
Spectroscopic Studies ◽  
Capture Process ◽  
Raman Spectroscopic

Operando Raman spectroscopy allowed following up the phase evolution for K-doped lithium zirconates during the CO2 capture process.

scholarly journals Raman spectroscopic studies and DFT calculations on NaCH3CO2 and NaCD3CO2 solutions in water and heavy water

RSC Advances ◽  
2015 ◽  
Vol 5 (28) ◽  
pp. 21897-21908 ◽  
Author(s):  
Wolfram W. Rudolph ◽  
Gert Irmer
Keyword(s):  
Raman Spectroscopy ◽  
Dft Calculations ◽  
Heavy Water ◽  
Sodium Acetate ◽  
Water Clusters ◽  
Spectroscopic Studies ◽  
Wide Concentration Range ◽  
Raman Spectroscopic

Sodium acetate and acetate-d3 solutions in water and heavy water were studied using Raman spectroscopy over a wide concentration range from 40–4200 cm−1 and DFT calculations were performed on acetate–water clusters.

scholarly journals Voigt Transform and Umbral Image

2020 ◽  
Vol 25 (3) ◽  
pp. 49
Author(s):  
Silvia Licciardi ◽  
Rosa Maria Pidatella ◽  
Marcello Artioli ◽  
Giuseppe Dattoli
Keyword(s):  
Spectroscopic Studies ◽  
Higher Order ◽  
Point Of View ◽  
The Other ◽  
Pivotal Role ◽  
Umbral Calculus ◽  
Laguerre Functions ◽  
Hermite And Laguerre Functions ◽  
Higher Order Functions ◽  
Voigt Function

In this paper, we show that the use of methods of an operational nature, such as umbral calculus, allows achieving a double target: on one side, the study of the Voigt function, which plays a pivotal role in spectroscopic studies and in other applications, according to a new point of view, and on the other, the introduction of a Voigt transform and its possible use. Furthermore, by the same method, we point out that the Hermite and Laguerre functions, extension of the corresponding polynomials to negative and/or real indices, can be expressed through a definition in a straightforward and unified fashion. It is illustrated how the techniques that we are going to suggest provide an easy derivation of the relevant properties along with generalizations to higher order functions.

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