Quantitative Characterization of Aqueous Suspensions using Variable-Angle ATR-FTIR Spectroscopy:  Determination of Optical Constants and Absorption Coefficient Spectra

Langmuir ◽  
1997 ◽  
Vol 13 (18) ◽  
pp. 4829-4836 ◽  
Author(s):  
Lane D. Tickanen ◽  
M. Isabel Tejedor-Tejedor ◽  
Marc A. Anderson
Keyword(s):  
Absorption Coefficient ◽  
Ftir Spectroscopy ◽  
Optical Constants ◽  
Quantitative Characterization ◽  
Aqueous Suspensions ◽  
Variable Angle

Quantitative Characterization of True Leak Rate of Micro to Nanoliter Packages Using a Helium Mass Spectrometer

2007 ◽  
Author(s):  
A. Goswami ◽  
B. Han ◽  
Suk-Jin Ham ◽  
Byung-Gil Jeong
Keyword(s):  
Qualitative Analysis ◽  
Mass Spectrometer ◽  
Linear Regression Analysis ◽  
Quantitative Measure ◽  
Leak Rate ◽  
Accelerated Tests ◽  
Quantitative Characterization ◽  
Rf Filter

The helium mass spectrometer has been used extensively for qualitative analysis of fine leaks. However, qualitative analysis for the small volumes (typically < 10−3 cc) of MEMS packages can produce erroneous results. In addition, the qualitative use of the helium fine leak test does not allow comparison of two different packages. Nor can the results be correlated with data from accelerated tests such as 85°C/85%RH test. These limitations warrant the development of a method to assess hermeticity quantitatively. This paper proposes a procedure to quantitatively measure the true leak rate of micro to nanoliter packages using the helium mass spectrometer. The proposed method is based on the fact that the profile of the measured leak rate signal depends only on the true leak rate and the volume of the package. Prior knowledge of the volume of the package enables determination of the true leak rate by performing a weighted non-linear regression analysis of the data. The method was implemented to measure the true leak rate of a MEMS RF filter package. The package was tested under three different test conditions yielding three different signal profiles. The method yielded a consistent value for the true leak rate, which verified the robustness of the method. The proposed method provides a true leak rate as a quantitative measure of hermeticity. The accurate true leak rates will help evaluate new bonding materials/processes and package designs fast and effectively.

State of Aircraft Turboshaft Engines by Means of Tribotechnical Diagnostic

2018 ◽  
Vol 35 (1) ◽  
pp. 11-16 ◽  
Author(s):  
Janka Mihalčová
Keyword(s):  
Chemical Elements ◽  
Friction Pair ◽  
Optical Emission ◽  
Emission Spectrometry ◽  
Rotating Disc ◽  
Quantitative Characterization ◽  
Qualitative And Quantitative ◽  
Friction Regime

AbstractThe contribution describes concrete example of application of tribotechnical methods for the determination of the bearing wear state in aircraft turboshaft engines. Tribotechnical methods, which will be mentioned, deal with qualitative and quantitative characterization of particles occurred in oil. Here belong method optical emission spectrometry method with rotating disc electrode for determination of chemical elements concentration in oil. Method of optical particles counting for detection of particles distribution according to their scale, determination of their number and ferrographic analysis. Exploitation of these methods make it possible to determine quickly and correctly the friction regime and wearing of friction pair that is washed by oil in observed engines.

Synthesis of Polypropylene-Graft-Polycaprolactone by Melt-Grafting

2006 ◽  
Vol 11-12 ◽  
pp. 465-468
Author(s):  
Yuan Sui ◽  
Jian Ping Deng ◽  
Wan Tai Yang
Keyword(s):  
Fourier Transform ◽  
Thermogravimetric Analysis ◽  
Ftir Spectroscopy ◽  
1H Nmr ◽  
Graft Copolymerization ◽  
Quantitative Characterization ◽  
X Ray ◽  
Qualitative And Quantitative ◽  
Melt Grafting

Polypropylene (PP) was modified by melt graft copolymerization with ε-caprolactone (ε-CL) in the absence of initiator. Fourier transform infrared (FTIR) spectroscopy was used for qualitative and quantitative characterization of the reaction product. The graft copolymer was also characterized by 1H NMR, x-ray and thermogravimetric analysis (TG).

Quantitative characterization of silica nanoparticles by asymmetric flow field flow fractionation coupled with online multiangle light scattering and ICP-MS/MS detection

2015 ◽  
Vol 30 (6) ◽  
pp. 1266-1273 ◽  
Author(s):  
Federica Aureli ◽  
Marilena D'Amato ◽  
Andrea Raggi ◽  
Francesco Cubadda
Keyword(s):  
Light Scattering ◽  
Flow Field ◽  
Silica Nanoparticles ◽  
Mass Concentration ◽  
Field Flow Fractionation ◽  
Asymmetric Flow ◽  
Quantitative Characterization ◽  
Icp Ms

A reliable and sensitive analytical method for the simultaneous determination of size and mass concentration of silica nanoparticles sized 20–200 nm.

scholarly journals Characterization of In(Ga,Al)As/GaAs metamorphic heterostructures for mid-IR emitters by FTIR photoreflectance spectroscopy

2021 ◽  
Vol 2086 (1) ◽  
pp. 012140
Author(s):  
D D Firsov ◽  
M Yu Chernov ◽  
V A Solov’ev ◽  
O S Komkov
Keyword(s):  
Electric Field ◽  
Ftir Spectroscopy ◽  
Critical Point ◽  
Free Carrier ◽  
Interband Transitions ◽  
Spectroscopy Technique ◽  
Fabry Perot ◽  
Contactless Control

Abstract Infrared photoreflectance (PR) spectra of In(Ga,Al)As/GaAs metamorphic heterostructures have been obtained using a novel photomodulation FTIR spectroscopy technique. An analysis of the PR spectra features allowed us to estimate the critical point energies corresponding to the direct interband transitions in various regions of the In(Ga,Al)As heterostructures, and distinguish the PR signals originating from Fabry-Perot interference. Observation of Franz-Keldysh oscillations originating from the InAlAs virtual substrate and an InGaAs waveguide layer has enabled determination of the built-in electric field intensities within the heterostructures. The obtained results open up possibilities for contactless control of free carrier concentration in In(Ga,Al)As/GaAs metamorphic heterostructures developed for growth of emitters of mid-IR spectral range.

scholarly journals Quantitative and Qualitative Characterization of Gentiana rigescens Franch (Gentianaceae) on Different Parts and Cultivations Years by HPLC and FTIR Spectroscopy

2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Lu-Ming Qi ◽  
Ji Zhang ◽  
Yan-Li Zhao ◽  
Zhi-Tian Zuo ◽  
Hang Jin ◽  
...  
Keyword(s):  
Medicinal Plant ◽  
Ftir Spectroscopy ◽  
Metabolic Profile ◽  
Iridoid Glycosides ◽  
Ftir Spectra ◽  
Comprehensive Investigation ◽  
Gentiana Rigescens ◽  
Different Parts

Gentiana rigescens Franch (Gentianaceae) is a famous medicinal plant for treatments of rheumatism, convulsion, and jaundice. Comprehensive investigation of different parts and cultivation years of this plant has not yet been conducted. This study presents the quantitative and qualitative characterization of iridoid glycosides from G. rigescens performed by HPLC and FTIR spectroscopy techniques. The accumulations of loganic acid, swertiamarin, gentiopicroside, and sweroside were determined. Results indicated that their content and distribution in different parts and cultivation years exhibit great variations. Gentiopicroside was identified as the most abundant compound among iridoid glycosides and its highest level was observed in the root of 2-year-old plant. With respect to qualitative variation of metabolic profile, the 1800–800 cm−1 band of FTIR spectra successfully discriminated different parts and cultivation years with the aid of PLS-DA. In addition, combined with PLSR, the feasibility of FTIR spectroscopy for determination of gentiopicroside was investigated by selecting characteristic wavelengths (1800–800 cm−1), which presented a good performance with a residual predictive deviation (RPD) of 3.646. Our results suggested that HPLC and FTIR techniques can complement each other and could be simultaneously applied for comparing and analyzing different parts and cultivation years of G. rigescens.

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