scholarly journals A High-Precision Fast-Response Airborne CO2Analyzer for In Situ Sampling from the Surface to the Middle Stratosphere

2002 ◽  
Vol 19 (10) ◽  
pp. 1532-1543 ◽  
Author(s):  
B. C. Daube ◽  
K. A. Boering ◽  
A. E. Andrews ◽  
S. C. Wofsy
Keyword(s):  
High Precision ◽  
Fast Response ◽  
Middle Stratosphere

Ion track etching of polycarbonate membranes monitored by in situ small angle X-ray scattering

2021 ◽  
Author(s):  
Alexander Kiy ◽  
Christian Notthoff ◽  
Shankar Dutt ◽  
Mark Grigg ◽  
Andrea Hadley ◽  
...  
Keyword(s):  
High Precision ◽  
Small Angle ◽  
Selective Dissolution ◽  
X Ray ◽  
Ion Tracks ◽  
X Ray Scattering ◽  
Track Etching ◽  
Polycarbonate Membranes ◽  
Ray Scattering

In situ small angle X-ray scattering (SAXS) measurements of ion track etching of polycarbonate foils are used to directly monitor the selective dissolution of ion tracks with high precision, including...

New Miniaturized and Space Qualified Gas Sensors for Fast Response In Situ Measurements

2010 ◽  
Author(s):  
Stefanos Fasoulas ◽  
Tino Schmiel ◽  
Rainer Baumann ◽  
Martin Hoerenz ◽  
Frank Hammer ◽  
...  
Keyword(s):  
Gas Sensors ◽  
Fast Response ◽  
In Situ Measurements

scholarly journals In-situ observations of the isotopic composition of methane at the Cabauw tall tower site

2016 ◽  
Author(s):  
Thomas Röckmann ◽  
Simon Eyer ◽  
Carina van der Veen ◽  
Maria E. Popa ◽  
Béla Tuzson ◽  
...  
Keyword(s):  
Isotopic Composition ◽  
High Precision ◽  
Temporal Resolution ◽  
Isotope Ratio ◽  
Mesoscale Model ◽  
Ambient Air ◽  
Model Calculations ◽  
Dual Isotope ◽  
Methane Budget

Abstract. High precision analyses of the isotopic composition of methane in ambient air can potentially be used to discriminate between different source categories. Due to the complexity of isotope ratio measurements, such analyses have generally been performed in the laboratory on air samples collected in the field. This poses a limitation on the temporal resolution at which the isotopic composition can be monitored with reasonable logistical effort. Here we present the performance of a dual isotope ratio mass spectrometric system (IRMS) and a quantum cascade laser absorption spectroscopy (QCLAS) based technique for in-situ analysis of the isotopic composition of methane under field conditions. Both systems were deployed at the Cabauw experimental site for atmospheric research (CESAR) in the Netherlands and performed in-situ, high-frequency (approx. hourly) measurements for a period of more than 5 months. The IRMS and QCLAS instruments were in excellent agreement with a slight systematic offset of +(0.05 ± 0.03) ‰ for δ13C and –(3.6 ± 0.4) ‰ for δD. This was corrected for, yielding a combined dataset with more than 2500 measurements of both δ13C and δD. The high precision and temporal resolution dataset does not only reveal the overwhelming contribution of isotopically depleted agricultural CH4 emissions from ruminants at the Cabauw site, but also allows the identification of specific events with elevated contributions from more enriched sources such as natural gas and landfills. The final dataset was compared to model calculations using the global model TM5 and the mesoscale model FLEXPART-COSMO. The results of both models agree better with the measurements when the TNO-MACC emission inventory is used in the models than when the EDGAR inventory is used. This suggests that high-resolution isotope measurements have the potential to further constrain the methane budget, when they are performed at multiple sites that are representative for the entire European domain.

scholarly journals In Situ Vapor Polymerization of Poly(3,4-ethylenedioxythiophene) Coated SnO2-Fe2O3 Continuous Electrospun Nanotubes for Rapid Detection of Iodide Ions

Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2084 ◽  
Author(s):  
Xiuru Xu ◽  
Wei Wang ◽  
Bolun Sun ◽  
Xue Zhang ◽  
Rui Zhao ◽  
...  
Keyword(s):  
In Situ Polymerization ◽  
Fast Response ◽  
Core Shell ◽  
Current Response ◽  
Electrospinning Technique ◽  
Iodide Ions ◽  
Wide Range ◽  
Vapor Phase Polymerization ◽  
Fe2o3 Nanotubes

In this work poly(3,4-ethylenedioxythiophene) (PEDOT) coated SnO2-Fe2O3 continuous nanotubes with a uniform core–shell structure have been demonstrated for rapid sensitive detection of iodide ions. The SnO2-Fe2O3 nanotubes were firstly fabricated via an electrospinning technique and following calcination process. An in situ polymerization approach was then performed to coat a uniform PEDOT shell on the surface of as-prepared SnO2-Fe2O3 nanotubes by vapor phase polymerization, using Fe2O3 on the surface of nanotubes as an oxidant in an acidic condition. The resultant PEDOT@SnO2-Fe2O3 core-shell nanotubes exhibit a fast response time (~4 s) toward iodide ion detection and a linear current response ranging from 10 to 100 μM, with a detection limit of 1.5 μM and sensitivity of 70 μA/mM/cm2. The facile fabrication process and high sensing performance of this study can promote a wide range of potential applications in human health monitoring and biosensing systems.

Continuous measurement of gas partial pressures in intracerebral tissue

1978 ◽  
Vol 44 (4) ◽  
pp. 528-533 ◽  
Author(s):  
J. Seylaz ◽  
E. Pinard
Keyword(s):  
Continuous Measurement ◽  
Fast Response ◽  
Base Line ◽  
Partial Pressures ◽  
Mass Spectrograph ◽  
Present Technique ◽  
Gas Molecules ◽  
The Brain ◽  
Thin Polyethylene

A mass spectrograph technique has been developed for measurement of physiological gas partial pressures locally in the brain. The sampling cannula is implanted stereotaxically and remains in situ for several weeks. It is a thin cylinder in shape, and is covered with a thin polyethylene membrane across which gas molecules can be sampled continuously. The conductance of this membrane is well adapted to the limited rate of replacement of gas molecules afforded by the cerebral tissue, hence there is no depletion around the cannula; this depletion has until now been the major problem of this technology. The present technique provides a continuous measurement with fast response time, which is directly proportional to the partial pressures of the gases. The variations can be expressed as a percentage of the base-line value.

scholarly journals In situ wide-field visualization of palladium hydrogenation

2020 ◽  
Author(s):  
Chongjun Jin ◽  
Nicholas Fang ◽  
Xiaoyi She ◽  
Huifeng Du ◽  
Yang Shen ◽  
...  
Keyword(s):  
Real Time ◽  
Hydrogen Diffusion ◽  
Fast Response ◽  
Wide Field ◽  
Ion Diffusion ◽  
Optical Contrast ◽  
Self Organized ◽  
Transmission Electron ◽  
Kinetics Of

Abstract Visualizing hydrogenation processes in metals in real-time is important to various hydrogen-involved applications. However, observing hydrogen diffusion was limited by transmission electron microscopy, and the kinetics of hydrogenation in the interior of the metals was not reported. Here we proposed an optical microscopy-based visualization of palladium hydrogenation from diffusion surface to the interior by introducing a fast-response mechanical platform that transforms the hydrogen diffusion into self-organized ordered wrinkles with sharp optical contrast. This platform is an Au/Pd double layer on elastomer which results in directional hydrogenation from sidewall to the interior. The kinetics of hydrogenation in the interior of the palladium along the diffusion direction was monitored in real-time. This platform will enable in-situ visualization of atom/ion diffusion on metals that are crucial in energy storage and hydrogen detection.

scholarly journals Capacitive type Humidity Sensor based on PANI decorated Cu-Zns Porous Micropshere

2020 ◽  
Author(s):  
Jolly Bhadra ◽  
Hemalatha Parangusan ◽  
Zubair Ahmad ◽  
Shoaib Mallick ◽  
Farid Touati ◽  
...  
Keyword(s):  
Humidity Sensor ◽  
In Situ Polymerization ◽  
Fast Response ◽  
Polymerization Process ◽  
Average Response ◽  
Surface Absorption ◽  
Absorption Properties ◽  
Recovery Times ◽  
Response And Recovery

PANI coated Cu-ZnS porous microsphere structures have been synthesized by hydrothermal method and in-situ polymerization process. The synthesized composite is characterized by different techniques in order to study the structural, morphological and surface absorption properties. The experimental observation demonstrates that the PANI/1%Cu-ZnS composite has better sensitivity, fast response and good stability as compared to pure PANI and other PANI/CuZnS compositions. Finally, PANI/1% Cu-ZnS composite has been found to be optimized for the humidity sensors due to its well-distributed roughness, porosity and hydrophilicity. The average response and recovery times of the PANI/1% Cu-ZnS are found to be 42 s and 24 s, respectively, which outperform recent results.

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