Micro-Raman Spectroscopic Observation of Water Expulsion Induced Destruction of Hydrophobic Clusters in Crystalline Lysozyme

2009 ◽  
Vol 113 (29) ◽  
pp. 9633-9635 ◽  
Author(s):  
Jing-Jing Shou ◽  
Guang Zeng ◽  
Yun-Hong Zhang ◽  
G. Q. (Max) Lu
Keyword(s):  
Spectroscopic Observation ◽  
Raman Spectroscopic

In situ Raman Spectroscopic Observation of Polymer Chains in Semi-Crystalline Polyethylene Solids

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Yusuke Hiejima ◽  
Takumitsu Kida ◽  
Koh-hei Nitta
Keyword(s):  
Conformational Changes ◽  
Tensile Elongation ◽  
Spectroscopic Observation ◽  
Polymer Chains ◽  
Trans Conformation ◽  
Raman Spectroscopic ◽  
Higher Temperature ◽  
Microscopic Origin ◽  
Crystalline Polyethylene

AbstractIn situ Raman spectroscopy is applied for polyethylene solid under various environments to elucidate the morphological and conformational changes. The trans conformation retains up to higher temperature for high-density polyethylene, reflecting higher stability of the orthorhombic crystals composed of stacked trans chains. It is suggested that the conversion of the non-crystalline trans chains to the crystalline phase is the microscopic origin of thermal history in the crystallinity, whereas the transformation between the trans and gauche conformers is practically in thermal equilibrium. Microscopic and dynamic mechanism of deformation during uniaxial stretching is investigated for the molecular orientation and the microscopic load sharing on the crystalline and amorphous chains. Lower crystallinity results in smoother and higher orientation toward the stretching direction, as well as higher load on the amorphous chains, during tensile elongation.

Cigarette smoke-induced changes in the murine vocal folds: a Raman spectroscopic observation

The Analyst ◽  
2020 ◽  
Vol 145 (23) ◽  
pp. 7709-7717
Author(s):  
Elizabeth Erickson-DiRenzo ◽  
S. P. Singh ◽  
Joshua D. Martinez ◽  
Santiago E. Sanchez ◽  
Meena Easwaran ◽  
...  
Keyword(s):  
Cigarette Smoke ◽  
Molecular Level ◽  
Vocal Folds ◽  
Spectroscopic Observation ◽  
Spectroscopic Methods ◽  
Label Free ◽  
Raman Spectroscopic ◽  
Induced Changes

Raman spectroscopic methods are being projected as novel tools to study the early invisible molecular level changes in the vocal folds in a label-free manner.

Raman-Spectroscopic Observation of the Σ-diads of 12C16O18O and 12C16O17O

1977 ◽  
Vol 32 (9) ◽  
pp. 1070-1071 ◽  
Author(s):  
K. Srinivasan ◽  
H. Finsterhölzl ◽  
H. W. Klöckner ◽  
D. Illig ◽  
H. W. Schrötter
Keyword(s):  
Raman Spectrum ◽  
Spectroscopic Observation ◽  
Fermi Resonance ◽  
Raman Spectroscopic

AbstractThe Fermi resonance doublets of 12C16O18O and 12C16O17O were identified as weak Q-branches in the Raman spectrum of natural CO2.

Raman spectroscopic observation of dehydrogenation in ball-milled LiNH2–LiBH4–MgH2 nanoparticles

2010 ◽  
Vol 35 (12) ◽  
pp. 6323-6331 ◽  
Author(s):  
Jason R. Hattrick-Simpers ◽  
James E. Maslar ◽  
Michael U. Niemann ◽  
Chun Chiu ◽  
Sesha S. Srinivasan ◽  
...  
Keyword(s):  
Spectroscopic Observation ◽  
Raman Spectroscopic

Raman Spectroscopic Observation of Laser-Induced Oxidation of Transition-Metal Borides, Carbides, and Nitrides

1989 ◽  
Vol 43 (1) ◽  
pp. 134-138 ◽  
Author(s):  
G. M. Begun ◽  
C. E. Bamberger
Keyword(s):  
Raman Spectra ◽  
Laser Power ◽  
Spectroscopic Observation ◽  
Laser Power Density ◽  
Oxide Formation ◽  
Raman Spectroscopic ◽  
Laser Raman ◽  
Surface Oxides ◽  
Raman Microprobe ◽  
Metal Borides

Laser Raman microprobe examination in air of small-particle-sized (powders and whiskers) TiN, TiB2, TiC, WC, ZrN, and NbN revealed the formation of surface oxides, which were induced by laser heating. The rate of oxide formation varied with the particle size of the samples and the laser power density applied. The oxides produced were characterized by their Raman spectra. Thus, the Raman spectra obtained with a microprobe should always be carefully analyzed to ascertain whether oxidation or decomposition of so-called inert materials, especially in powder form, has occurred.

In situ Raman spectroscopic observation of the temperature-dependent partition of CH4 and CO2 during the growth of double hydrate from aqueous solution

2015 ◽  
Vol 93 (9) ◽  
pp. 970-975 ◽  
Author(s):  
Feifei Wang ◽  
Changling Liu ◽  
Wanjun Lu ◽  
Jiasheng Wang ◽  
Yuguang Ye
Keyword(s):  
Aqueous Solution ◽  
Spectroscopic Observation ◽  
Dissolved Gas ◽  
Temperature Dependent ◽  
Optical Cell ◽  
Raman Spectroscopic ◽  
Oceanic Sediments ◽  
Equilibrium Concentrations ◽  
Lower Temperature

Sequestration of CO2 in hydrate form within deep oceanic sediments, to simultaneously replace methane trapped in submarine hydrate, has been considered as an efficient method for CO2 reduction. Consequently, research efforts are underway to deeply understand the properties of CH4 and CO2 hydrates. In this work, CH4 + CO2 double hydrate crystals were grown from aqueous solution in a capillary high-pressure optical cell. The quantitative relationships between Raman intensity and dissolved gas (i.e., CH4 and CO2) concentration in water and in hydrate were established. The partition coefficients of CH4 and CO2 between the hydrate and aqueous phases were measured at 5 constant temperatures from 275.15 to 293.15 K. The equilibrium concentrations of dissolved CH4 and CO2 decrease with decreasing temperatures, indicating more dissolved CH4 and CO2 will be transferred from the aqueous to the hydrate phase at lower temperature. With decreasing temperature, the molality of CO2 in hydrate increases and the molality of CH4 in 51262 cavities decreases, while the sum of the molality of CH4 in 51262 cavities and molality of CO2 in hydrate keeps constant, indicating that CO2 molecules can replace more methane molecules under lower temperature only by occupying the 51262 cavities.

Sign in / Sign up

Export Citation Format

Share Document