Mutual Diffusion Driven NMR: a new approach for the analysis of mixtures by spatially resolved NMR spectroscopy

Spatially resolved flame temperatures are spectroscopically measured using the slope method, over small (≃0.7 μl), relatively homogenous volumes of flame gases. The spatial resolution is uniquely obtained by introducing Co as a thermometric species into isolated volumes via the use of a droplet injection technique. By this method the emission of light is restricted to a limited volume, whose position in the flame can be accurately determined and controlled. Vertical resolution is determined by the width of the entrance slit of the monochromator employed (100 μm in this study), and horizontal resolution is limited by the width of the emission cloud formed by the injected droplets (1 to 3 mm). The possibility of self-absorption effects are greatly reduced because of the short radiation path length involved. The performance of the method is illustrated by its application to the spatial temperature mapping of the secondary reaction zone of a cylindrical air-acetylene flame. The effects of N2 as a sheathing gas and flame stoichiometry on the radial and vertical temperature distribution of the flame are also investigated. It is determined that a large, virtually isothermal, central zone exists in the flame.

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Imaging of brain tissue pH and metabolites. A new approach for the validation of volume-selective NMR spectroscopy

NMR in Biomedicine ◽

10.1002/nbm.1940020512 ◽

1989 ◽

Vol 2 (5-6) ◽

pp. 240-245 ◽

Cited By ~ 17

Author(s):

M. Höhn-Berlage ◽

Y. Okada ◽

O. Kloiber ◽

K.-A. Hossmann

Keyword(s):

Nmr Spectroscopy ◽

Brain Tissue ◽

New Approach ◽

Tissue Ph

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Enhanced Hydrogenation Due to Ultrasound Treatment in Polycrystalline Silicon: New Approach to Thin Film Defect Engineering

MRS Proceedings ◽

10.1557/proc-378-405 ◽

1995 ◽

Vol 378 ◽

Author(s):

S. Ostapenko ◽

W. Henley ◽

S. Karimpanakkel ◽

L. Jastrzebski ◽

J. Lagowski

Keyword(s):

Thin Film ◽

Polycrystalline Silicon ◽

Thin Film Transistor ◽

Ultrasound Treatment ◽

Defect Engineering ◽

New Approach ◽

Glass Substrates ◽

Spatially Resolved ◽

Order Of Magnitude ◽

Film Defect

AbstractWe applied the ultrasound treatment (UST) to improve properties of poly-Si thin films on glass substrates for thin-film transistor applications. A strong decrease of the sheet resistivity in hydrogenated films subjected to UST was observed. UST improves the film homogeneity as monitored by spatially resolved surface photovoltage mapping. Studies of hydrogenated thin-film transistors demonstrated remarkable UST induced improvement in transistor characteristics, especially, a reduction of leakage current by as much as one order of magnitude. All these effects are explained in terms of UST enhanced hydrogenation of poly-Si film.

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Biphasic Liquid Crystal and the Simultaneous Measurement of Isotropic and Anisotropic Parameters by Spatially Resolved NMR Spectroscopy

Chemistry - A European Journal ◽

10.1002/chem.201702126 ◽

2017 ◽

Vol 23 (54) ◽

pp. 13351-13359 ◽

Cited By ~ 17

Author(s):

Malin Reller ◽

Svenja Wesp ◽

Martin R. M. Koos ◽

Michael Reggelin ◽

Burkhard Luy

Keyword(s):

Liquid Crystal ◽

Nmr Spectroscopy ◽

Simultaneous Measurement ◽

Spatially Resolved

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Spatially Resolved STD-NMR Applied to the Study of Solute Transport in Biphasic Systems: Application to Protein-Ligand Interactions

Natural Product Communications ◽

10.1177/1934578x19849789 ◽

2019 ◽

Vol 14 (5) ◽

pp. 1934578X1984978 ◽

Cited By ~ 1

Author(s):

Ridvan Nepravishta ◽

Serena Monaco ◽

Juan C. Muñoz-García ◽

Yaroslav Z. Khimyak ◽

Jesus Angulo

Keyword(s):

Nmr Spectroscopy ◽

Solute Exchange ◽

Spatially Resolved ◽

Protein Ligand Interactions ◽

Ligand Interactions ◽

Std Nmr ◽

Underlying Mechanisms ◽

Solute Dynamics ◽

Pharmacological Screening ◽

Biphasic Systems

Fluid biphasic systems are one of the most interesting dynamic systems in chemistry and biochemistry. In nuclear magnetic resonance (NMR) spectroscopy, the study of the solute dynamics across fluid biphasic systems requires the introduction of dedicated NMR methods, due to their intrinsic heterogeneity. Diffusion and spatially resolved NMR techniques represent a useful approach for dealing with the study of solutes in biphasic systems and have been applied lately with success. Nevertheless, other potential applications of NMR spectroscopy for biphasic systems remain to be explored. In this proof-of-concept communication, we specifically aimed to investigate whether solute exchange between two immiscible phases can be followed by NMR experiments involving transfer of magnetization. To that aim, we have used spatially resolved saturation transfer difference NMR (SR-STD NMR) experiments to analyze solute exchange by transfer of saturation from one phase to the other in a biphasic system and have explored which are the underlying mechanisms leading to the transfer of magnetization between phases and the limits of the approach. We hereby demonstrate that SR-STD NMR is feasible and that it might be implemented in pharmacological screening for binders of biological receptors or in the study of chemical and biochemical reactions occurring at interfaces.

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Super-Resolution Electrochemical Impedance Imaging with a 100 × 100 CMOS Sensor Array

10.1101/2021.08.19.456729 ◽

2021 ◽

Author(s):

Kangping Hu ◽

Christopher E. Arcadia ◽

Jacob K. Rosenstein

Keyword(s):

Sensor Array ◽

Electrochemical Impedance ◽

Super Resolution ◽

Integrated Sensor ◽

New Approach ◽

Impedance Imaging ◽

Spatially Resolved ◽

M 10 ◽

Cmos Sensor ◽

Mutual Capacitance

AbstractThis paper presents a 100 × 100 super-resolution integrated sensor array for microscale electrochemical impedance spectroscopy (EIS) imaging. The system is implemented in 180 nm CMOS with 10 μm × 10 μm pixels. Rather than treating each electrode independently, the sensor is designed to measure the mutual capacitance between programmable sets of pixels. Multiple spatially-resolved measurements can then be computationally combined to produce super-resolution impedance images. Experimental measurements of sub-cellular permittivity distributions within single algae cells demonstrate the potential of this new approach.

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