Temperature Measurement of Single Levitated Microparticles Using Stokes/Anti-Stokes Raman Intensity Ratios

1994 ◽  
Vol 48 (12) ◽  
pp. 1498-1505 ◽  
Author(s):  
Scot D. Rassat ◽  
E. James Davis
Keyword(s):  
Temperature Measurement ◽  
Calcium Nitrate ◽  
Composition Analysis ◽  
Calcium Nitrate Tetrahydrate ◽  
Electrodynamic Balance ◽  
Beam Expander ◽  
Nitrate Tetrahydrate ◽  
Intensity Ratios ◽  
Anti Stokes ◽  
Heating Beam

A method has been developed to determine the temperature of single microparticles levitated in an electrodynamic balance. Particle temperatures were ascertained from the measured intensities of the Stokes and anti-Stokes Raman spectra. Temperatures near ambient were obtained for titanium dioxide and calcium nitrate microparticles with the use of a Raman-based calibration of the optical system to correct for wavelength-dependent effects. Higher temperatures were also measured with the use of a carbon dioxide infrared laser to electromagnetically heat the particle. In an effort to minimize particle instabilities caused by the heating beam, the Gaussian intensity profile of the beam was modified with an axicon beam expander to produce a doughnut-like intensity distribution. The temperature measurement technique and quantitative Raman composition analysis were applied to study dehydration of a calcium nitrate tetrahydrate particle.

scholarly journals Synthesis of plate-like β-tricalcium phosphate nanoparticles and their efficiency in remineralization of incipient enamel caries

2019 ◽  
Vol 8 (4) ◽  
pp. 261-276
Author(s):  
Roghayyeh Marefat Seyedlar ◽  
Mohammadbagher Rezvani ◽  
Samira Barari ◽  
Mohammad Imani ◽  
Azizollah Nodehi ◽  
...  
Keyword(s):  
Tricalcium Phosphate ◽  
Calcium Nitrate ◽  
Negative Control ◽  
Second Phase ◽  
Calcium Nitrate Tetrahydrate ◽  
Enamel Caries ◽  
Nitrate Tetrahydrate ◽  
Addition Rate ◽  
Post Hoc ◽  
Caries Lesions

AbstractThe purpose of this study was to synthesize nano-sized β-tricalcium phosphate (nano-TCP) particles and determine its concentration-dependent properties on incipient enamel caries lesions. Nano-TCP was synthesized as a wet chemical through a method using low concentration of precursors and low addition rate of calcium nitrate tetrahydrate as a second phase. Morphology and phase composition of the particles were analyzed by SEM, XRD, and EDXA techniques. Incipient enamel lesions were created in human premolars with an acidic buffer. The teeth were then incubated in aqueous dispersions of nano-TCP as remineralization solutions. Sodium fluoride solution and deionized water were used as positive and negative control groups, respectively. The quality and thickness of the remineralized layer on enamel were investigated using SEM. The data were statistically analyzed by analysis of variance (ANOVA) and post hoc Tukey’s test. The synthesized nano-TCP mostly consisted of porous platelet-like crystals of 50–100 nm thickness and pore diameters of 100–300 nm. SEM observation showed that a homogenous layer was formed on the surface of the enamels remineralized in nano-TCP solutions. The thickness of the mineralized layer was dependent on the incubation time and nano-TCP concentration.

Low temperature synthesis of wollastonite using sol–gel combustion method: In vitro bioactivity evaluation

2019 ◽  
Vol 33 (10) ◽  
pp. 1950081 ◽  
Author(s):  
Madeeha Riaz ◽  
Rehana Zia ◽  
Snudia Aslam ◽  
Alliya Qamar ◽  
Tousif Hussain ◽  
...  
Keyword(s):  
Low Temperature ◽  
Sol Gel ◽  
Calcium Nitrate ◽  
Combustion Method ◽  
Calcium Nitrate Tetrahydrate ◽  
In Vitro Bioactivity ◽  
Nitrate Tetrahydrate ◽  
Gel Combustion ◽  
Gel Combustion Method

In this paper, low temperature, economical sol–gel combustion method was adopted to synthesize wollastonite ceramic. Calcium nitrate tetrahydrate and tetraethyl orthosilicate were taken as source for Ca and Si, while citric acid and nitric acid were used as chelating/combustion agents. The yielded powder calcined at 600[Formula: see text]C for 4 h was characterized by FTIR, XRD and SEM techniques. Results showed that the citrate combustion method was the most efficient method to prepare wollastonite at low temperature. Moreover, in vitro bioactivity test performed in simulated body fluid (SBF) showed good bioactivity of synthesized wollastonite ceramics.

Densities and viscosities of urea-calcium nitrate tetrahydrate melts

1984 ◽  
Vol 29 (1) ◽  
pp. 14-16
Author(s):  
Surender K. Jain ◽  
Niraj P. Kulshrestha ◽  
Vijay V. Singh
Keyword(s):  
Calcium Nitrate ◽  
Calcium Nitrate Tetrahydrate ◽  
Nitrate Tetrahydrate
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