A non-destructive test to assess the axial heterogeneity of in situ modified monoliths for HPLC

2015 ◽  
Vol 7 (17) ◽  
pp. 7177-7185 ◽  
Author(s):  
Danielle N. Bassanese ◽  
Arianne Soliven ◽  
Xavier A. Conlan ◽  
R. Andrew Shalliker ◽  
Neil W. Barnett ◽  
...  
Keyword(s):  
Density Gradient ◽  
Surface Coverage ◽  
Theoretical Studies ◽  
Band Broadening ◽  
Destructive Test ◽  
Coverage Density ◽  
Non Destructive ◽  
Peak Parking ◽  
Qualitative Changes

A multi-location peak parking protocol was developed for a non-destructive assessment of the axial heterogeneity of in situ modified monoliths. This was tested on a column with a surface coverage density gradient along the length of the monolithic rod. Qualitative changes in band broadening were observed and were consistent with theoretical studies.

scholarly journals Diagnosing in Situ Concrete by Some Non-Destructive Test Methods

1994 ◽  
Vol 5 (1) ◽  
pp. 15-22
Author(s):  
Shoji Amasaki ◽  
Kazuhiro Kuzume ◽  
Toyoaki Miyagawa
Keyword(s):  
Test Methods ◽  
Destructive Test ◽  
Non Destructive

In Situ Determination of the Elastic Modulus of Concrete by Means of Ultrasonic Pulse Method

2018 ◽  
Vol 272 ◽  
pp. 70-75
Author(s):  
Petr Cikrle ◽  
Dalibor Kocáb ◽  
Barbara Kucharczyková ◽  
Ondřej Anton
Keyword(s):  
Elastic Modulus ◽  
Pulse Method ◽  
Ultrasonic Pulse ◽  
In Situ Measurements ◽  
Test Method ◽  
Destructive Test ◽  
Non Destructive ◽  
Thick Layers

The paper deals with the in-situ determination of the modulus of elasticity on the bridge elements using ultrasonic pulse method. This non-destructive test method was chosen for the measurement because of its undisputed advantages that allow the measurement of relatively thick layers of material. For the purpose of the elastic modulus verification the direct measurement was used, in which a pair of transducers (transmitter and receiver) were placed directly opposite to each other. The results of performed in-situ measurements as well as the results of verification tests performed in the laboratory are presented in the paper. The article also discusses the issue of evaluation and interpretation of the results obtained by in-situ measurements using non-destructive test method.

The Nature of Chemisorbed CO2 in Zeolite A

2019 ◽  
Author(s):  
Przemyslaw Rzepka ◽  
Zoltán Bacsik ◽  
Andrew J. Pell ◽  
Niklas Hedin ◽  
Aleksander Jaworski
Keyword(s):  
Solid State ◽  
Ir Spectroscopy ◽  
Quantum Chemical Calculations ◽  
Quantum Chemical ◽  
Surface Coverage ◽  
Gas Mixtures ◽  
Mas Nmr ◽  
Significant Fraction ◽  
Zeolite A

Formation of CO<sub>3</sub><sup>2-</sup> and HCO<sub>3</sub><sup>-</sup> species without participation of the framework oxygen atoms upon chemisorption of CO<sub>2</sub> in zeolite |Na<sub>12</sub>|-A is revealed. The transfer of O and H atoms is very likely to have proceeded via the involvement of residual H<sub>2</sub>O or acid groups. A combined study by solid-state <sup>13</sup>C MAS NMR, quantum chemical calculations, and <i>in situ</i> IR spectroscopy showed that the chemisorption mainly occurred by the formation of HCO<sub>3</sub><sup>-</sup>. However, at a low surface coverage of physisorbed and acidic CO<sub>2</sub>, a significant fraction of the HCO<sub>3</sub><sup>-</sup> was deprotonated and transformed into CO<sub>3</sub><sup>2-</sup>. We expect that similar chemisorption of CO<sub>2</sub> would occur for low-silica zeolites and other basic silicates of interest for the capture of CO<sub>2</sub> from gas mixtures.

scholarly journals Laser-excited elastic guided waves reveal the complex mechanics of nanoporous silicon

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Marc Thelen ◽  
Nicolas Bochud ◽  
Manuel Brinker ◽  
Claire Prada ◽  
Patrick Huber
Keyword(s):  
Guided Waves ◽  
Laser Ultrasonics ◽  
Bulk Silicon ◽  
Nanoporous Silicon ◽  
Stiffness Reduction ◽  
Mechanical Characterisation ◽  
Isotropic Elasticity ◽  
On Chip ◽  
Non Destructive

AbstractNanoporosity in silicon leads to completely new functionalities of this mainstream semiconductor. A difficult to assess mechanics has however significantly limited its application in fields ranging from nanofluidics and biosensorics to drug delivery, energy storage and photonics. Here, we present a study on laser-excited elastic guided waves detected contactless and non-destructively in dry and liquid-infused single-crystalline porous silicon. These experiments reveal that the self-organised formation of 100 billions of parallel nanopores per square centimetre cross section results in a nearly isotropic elasticity perpendicular to the pore axes and an 80% effective stiffness reduction, altogether leading to significant deviations from the cubic anisotropy observed in bulk silicon. Our thorough assessment of the wafer-scale mechanics of nanoporous silicon provides the base for predictive applications in robust on-chip devices and evidences that recent breakthroughs in laser ultrasonics open up entirely new frontiers for in-situ, non-destructive mechanical characterisation of dry and liquid-functionalised porous materials.

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