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Showing 1 to 14 of 14 for “"Micro gas chromatography"”.
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Semi-Packed Micro Gas Chromatography Columns
Separation of complex gaseous mixtures using gas chromatography (GC) is an important step in analytical systems for environmental monitoring, medical diagnosis, and forensic science. Due to its high resolving power, analysis speed, and small sample size, GC, has become the premier technique for …
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Density Modulated Semi-Packed Micro Gas Chromatography Columns
With the continued evolution of MEMS-based gas chromatography, the drive to develop new standalone systems with lower power consumptions and higher portability has increased. However, with improvements come tradeoffs, and trying to reduce the pressure drop requirements of previously reported …
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Design, Fabrication, and Evaluation of Micro Gas Chromatography Columns
… of these developments allows creating microcolumns with performance comparable to commercial fused silicon columns.
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Portable Micro-Gas Chromatography with Multidimensional Compound Identification Analysis
Gas Chromatography (GC) is an analytical technique in the chemistry field widely used to separate compounds present in a sample mixture. Conventional GC systems are an extremely versatile and powerful tool to perform complex separations. However, these systems come with the cost of being bulky and …
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MEMS-Based Micro Gas Chromatography: Design, Fabrication and Characterization
… characterization of high performance MEMS-based micro gas chromatography columns having wide range of applications in the pharmaceutical industry, environmental monitoring, petroleum distillation, clinical chemistry, and food processing. The first part of this work describes different approaches …
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Zebra GC: A Fully Integrated Micro Gas Chromatography System
A ready-to-deploy implementation of microfabricated gas chromatography (microGC) system characterized for detecting hazardous air pollutants (HAPs) at parts-per-billion (ppb) concentrations in complex mixtures has been described. A microfabricated preconcentrator (microPC), a MEMS separation column …
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Modular GC: A Fully Integrated Micro Gas Chromatography System
Gas Chromatography (GC) is one of the most important and widely used tools in analytical chemistry. However, they are bulky, have a longer measurement cycle, and consume a high amount of power. Micro-Gas Chromatography (µGC) is portable and energy-efficient, which allows onsite, real-time …
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Chemical Micro Preconcentrators Development for Micro Gas Chromatography Systems
Microelectromechanical systems (MEMS) technology allows the realization of mechanical parts, sensors, actuators and electronics on silicon substrate. An attractive utilization of MEMS is to develop micro instruments for chemical analysis. An example is gas chromatography (GC) which is widely used …
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Electrostatic Micro Gas Pumping for Micro Gas Chromatography Systems---Fabrication and Experiments
… diaphragm actuates. As an actuation compresses gas, the outlet valve should open with the inlet valve closed so that the gas flows out. As the diaphragm releases, the outlet valve closes and the inlet valve open, and the gas flows into the chamber. The volume of the pump chamber is 2∼6mul, …
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Methodology for Zero-Cost Auto-tuning of Embedded PID Controllers for Actuators: A Study on Proportional Valves in Micro Gas Chromatography Systems
… in the control of proportional valves within Micro Gas Chromatography (uGC) systems. uGC systems are miniaturized versions of conventional GC systems, and require precise temperature, flow and pressure control for the micro-fabricated preconcentrators and micro columns. PID controllers are …
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PID Auto-Tuning and Control System for Heaters in μGC Systems
Micro gas chromatography (μGC) system is a miniaturized and portable version of the conventional GC system, suitable for various applications such as healthcare and environmental analysis. The process of gas chromatography requires precise temperature control for the micro-fabricated …
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MicroGC: Of Detectors and their Integration
Gaseous phase is a critical state of matter around us. It mediates between the solid crust on earth and inter-stellar vacuum. Apart from the atmosphere surrounding us where compounds are present, natively, in a gaseous phase, they are also trapped within soil and dissolved in oceanic water. …
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Microfluidic Columns with Nanotechnology-Enabled Stationary Phases for Gas Chromatography
Advances in micro-electro-mechanical-systems (MEMS) along with nanotechnology based methods have enabled the miniaturization of analytical chemistry instrumentation. The broader aim is to provide a portable, low-cost, and low-power platform for the real-time detection and identification of organic …
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A Fast-Response Odor Chromatographic Sniffer (FOX)
This thesis in microscale gas chromatography (μGC) creates a paradigm shift in rapidly analyzing chemicals in the environment or analytes. We are looking for unexpected chemical changes that have been added purposefully or unintentionally. The work examines various aspects of μGC technology, …