Download or read book Development and Deployment of an Underwater Mass Spectrometer for Quantitative Measurements of Dissolved Gases written by Ryan J. Bell and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: Manual collection and processing of seawater samples for dissolved gas analyses are technically challenging, time consuming and costly. Accordingly, in situ analysis techniques present attractive alternatives to conventional gas measurement procedures. To meet the demands of sustained, high-resolution chemical observations of the oceans, the University of South Florida and SRI International developed underwater mass spectrometer systems for quantitative measurements of dissolved gases and volatile organic compounds. This work describes the influence of variable in situ conditions on the performance of a membrane introduction mass spectrometer used for measurements in both the water column and sediment porewater. Laboratory experiments to simulate the effects of field conditions on the membrane were performed by varying sample flow rate, salinity, hydrostatic pressure, and chemistry. Data indicate that membrane permeability has a strong dependence on hydrostatic pressure, and a weak dependence on salinity. Under slow flow conditions bicarbonates in solution contributed to carbon dioxide instrument response as a result of carbon system equilibration processes in the boundary layer at the membrane interface. In addition, method development was undertaken to enable underwater sediment porewater analyses and quantitative (calibrated) measurements of total dissolved inorganic carbon (DIC). This work establishes the capability of membrane introduction mass spectrometry to measure two compatible variables (DIC and dissolved CO2) for comprehensive CO2-system characterizations. In addition to laboratory studies three types of field observation were obtained in this work. High-resolution vertical profiles of dissolved gases in the Gulf of Mexico were obtained through system calibration and characterization of the influence of hydrostatic pressure on the behavior of polydimethylsiloxane membranes. In the South Atlantic Bight, sediment porewater profiles of dissolved gases were repeatedly obtained over a 54 hr period. Data trends were in agreement with high remineralization rates facilitated by porewater advection. Finally, time-series underwater DIC measurements that were undertaken proved to be in good accord with results obtained using conventional techniques. These measurements constitute the first quantitative observations of dissolved gas ocean profiles, sediment porewater profiles, and DIC measurements by underwater mass spectrometry.

Download or read book Development and Deployment of In Situ Mass Spectrometers written by and published by . This book was released on 2009 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objectives for this project were diverse, including underwater mass spectrometer (MS) deployments focusing on quantitative measurements of dissolved gases, and improvements on existing 200-amu systems and peripherals. Plume mapping capabilities were to be extended by integrating the underwater MS with a remotely operated vehicle (ROV), and by exploring methods to mathematically improve the spatial and temporal resolution of membrane introduction MS measurements. Instrumental developments (e.g., a novel, modular, deep-water syringe sampling pump system) were to further extend the analytical capabilities of the systems. In-line acidification methods were to be explored to more thoroughly study aqueous carbon systems in the field. Alternative membrane materials, such as carbon nanotubes, were also to be evaluated. Major accomplishments in each of these areas of research and development are discussed below.

Download or read book Applications to Marine Disaster Prevention written by Naomi Kato and published by Springer. This book was released on 2016-08-24 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book focuses on the recent results of the research project funded by a Grant-in-Aid for Scientific Research (S) of the Japan Society for the Promotion of Science (No. 23226017) from FY 2011 to FY 2015 on an autonomous spilled oil and gas tracking buoy system and its applications to marine disaster prevention systems from a scientific point of view. This book spotlights research on marine disaster prevention systems related to incidents involving oil tankers and offshore platforms, approaching these problems from new scientific and technological perspectives. The most essential aspect of this book is the development of a deep-sea underwater robot for real-time monitoring of blowout behavior of oil and gas from the seabed and of a new type of autonomous surface vehicle for real-time tracking and monitoring of oil spill spread and drift on the sea surface using an oil sensor. The mission of these robots is to provide the simulation models for gas and oil blowouts or spilled oil drifting on the sea surface with measured data for more precision of predictions of oil and gas behavior.

Download or read book Challenges and Innovations in Ocean In Situ Sensors written by Eric Delory and published by Elsevier. This book was released on 2018-09-21 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt: Challenges and Innovations in Ocean In-Situ Sensors: Measuring Inner Ocean Processes and Health in the Digital Age highlights collaborations of industry and academia in identifying the key challenges and solutions related to ocean observations. A new generation of sensors is presented that addresses the need for higher reliability (e.g. against biofouling), better integration on platforms in terms of size and communication, and data flow across domains (in-situ, space, etc.). Several developments are showcased using a broad diversity of measuring techniques and technologies. Chapters address different sensors and approaches for measurements, including applications, quality monitoring and initiatives that will guide the need for monitoring. Integrates information across key marine and maritime sectors and supports regional policy requirements on monitoring programs Offers tactics for enabling early detection and more effective monitoring of the marine environment and implementation of appropriate management actions Presents new technologies driving the next generation of sensors, allowing readers to understand new capabilities for monitoring and opportunities for another generation of sensors Includes a global vision for ocean monitoring that fosters a new perspective on the direction of ocean measurements

Download or read book Measurement of Dissolved Gas Concentrations in Natural Waters Utilizing an In situ Membrane Inlet Linear Quadrupole Mass Spectrometer written by Peter Wenner and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The resulting multi-analyte spectrometer data were recorded in real time with the Global Positioning System (GPS) observations of an associated surface vehicle and transmitted to a remote laptop computer via a wireless Ethernet link. These data were merged to create high-resolution maps of chemical distributions. Of particular interest were the co-varying oxygen and carbon dioxide mass spectrometer signals, diagnostic of photosynthesis-respiration processes, that were collected over a 10,800 square-meter area of the lake. The UMS was also deployed on a shipborne hydrowire in Saanich Inlet, a 200-meter deep fjord in the western Canadian province of British Columbia. The concentrations of a broad suite of dissolved gases were monitored on both downcast and upcast over a total depth range of 200 meters. Spectrometer data were acquired at a rate of 4.2 seconds/sample for the duration of the deployment.

Download or read book Identification and Quantitative Measurements of Chemical Species by Mass Spectrometry written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06 with total page 86 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of a miniature gas chromatograph/mass spectrometer system for the measurement of chemical species of interest to combustion is described. The completed system is a fully-contained, automated instrument consisting of a sampling inlet, a small-scale gas chromatograph, a miniature, quadrupole mass spectrometer, vacuum pumps, and software. A pair of computer-driven valves controls the gas sampling and introduction to the chromatographic column. The column has a stainless steel exterior and a silica interior, and contains an adsorbent of that is used to separate organic species. The detection system is based on a quadrupole mass spectrometer consisting of a micropole array, electrometer, and a computer interface. The vacuum system has two miniature pumps to maintain the low pressure needed for the mass spectrometer. A laptop computer uses custom software to control the entire system and collect the data. In a laboratory demonstration, the system separated calibration mixtures containing 1000 ppm of alkanes and alkenes.Zondlo, Mark A. and Bomse, David S.Glenn Research CenterMASS SPECTROMETERS; GAS CHROMATOGRAPHY; QUADRUPOLES; ALKENES; SILICON DIOXIDE; ELECTROMETERS; DETECTION; ALKANES; VACUUM PUMPS; MINIATURIZATION; LABORATORY EQUIPMENT

Download or read book Development Calibration and Deployment of an Airborne Chemical Ionization Mass Spectrometer for Trace Gas Measurements written by Talat Khattatov and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Adapting Membrane Inlet Mass Spectrometry for Accurate Measurements of Aquatic Noble Gases written by Sophia Meier and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: As inert species, the noble gases represent a useful tool for quantifying physical processes in aquatic environments. Thanks to their widely differing physical properties (solubility, diffusivity, etc.), each noble gas responds in a recognizable way to distinct types of physical forcing. Even though data on each gas is thus unique and valuable, data on the less abundant gases (neon, krypton, and xenon in particular) are not often used for analysis or even collected in the first place due to the difficulty in analyzing those gases at the required precision. We aimed to develop a method to measure neon, argon, krypton, and xenon in discrete water samples with Membrane-Inlet Mass Spectrometry (MIMS). MIMS technology uses a gaspermeable membrane to extract gas from samples inline with the mass spectrometer, eliminating the need for the tedious degassing steps prior to analysis employed by most other mass spectrometric methods. In theory, this allows for both (i) small sample sizes (on the order of milliliters instead of liters) unlike Equilibrator-Inlet Mass Spectrometry and (ii) fast throughput (multiple samples per hour) compared to traditional methods of aquatic noble gas measurements. Although many have used MIMS to measure argon, the most abundant noble gas, few have attempted to apply this technique to other noble gases. With the addition of getters to remove common atmospheric gases, we were able to develop a method to measure the relative amounts of neon, argon, krypton, and xenon in airequilibrated water using a membrane and a quadrupole mass spectrometer. We quantified the accuracy of the method as the percent difference between the measured and expected values for both the individual gases and the following ratios: Ne/Xe, Ar/Kr, Ne/Ar, Ar/Xe, and Kr/Xe. We explored many different variations of the experimental procedure to improve the accuracy of the method. Individual gas accuracy was maximized when sampling from a beaker mixed with a stir rod, at a flow rate of 0.6 mL/min and an evacuation time of 10 minutes without the dry ice and ethanol slurry. We hope that further modifying our parameters and procedure will improve the accuracy and precision of our data.

Download or read book In situ Calibration of Underwater Membrane Inlet Mass Spectrometer for Simple Dissolved Gases written by Samuel Gartzman and published by . This book was released on 2018 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Study of Dissolved Gases in Sea Water by Mass Spectrometry written by Edward Warren Pough and published by . This book was released on 1970 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Missionssange udgivne af Peter Jacobsen written by and published by . This book was released on 1898 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: Influencia da cultura em vasos sobre o desenvolvimento das plantas. Influencia da capacidade dos recipientes que se empregam na cultura das plantas. Inconvenientes dos reenvasamentos repetidos. Influencia da porosidade dos vasos empregados em horticultura. Disposicao dos vasos. Escolha das terras para as cultura em vasos. Rega das plants cultivadas em vasos. Oportunidade dos adubos nas culturas em vasos. Aplicacao dos adubos as culturas em vasos.

Download or read book Membrane Inlet Mass Spectrometry for Measuring Dissolved Gases written by G. Hudson and published by . This book was released on 2005 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Membrane Inlet Mass Spectrometer (MIMS) is used to measure dissolved gas concentrations in environmental water samples. Gases are exsolved out of water by passing the sample through a silicone gas permeable membrane that is under vacuum. A quadrupole mass spectrometer attached to the vacuum system is capable of measuring a variety of gases over a wide range of concentration. The MIMS is a versatile and field portable instrument.

Download or read book Development and Deployment of an Airborne Gas Chromatography Mass Spectrometer to Measure Tropospheric Volatile Organic Compounds written by Jamie K. Minaeian and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of a Field Portable Mass Spectrometer for Quantitative Analysis of Volatile Organic Compounds in Air written by Nicholas Davey and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The typical strategy for atmospheric analysis of volatile organic compounds(VOCs), is to collect discrete samples which are then transported to a laboratory foranalysis. This method has limited spatial and temporal resolution, and can be bothcostly and time consuming. To overcome these limitations, a mobile monitoringplatform was developed for real-time quantitative chemical analysis. This workdescribes the development of membrane introduction mass spectrometer andidenti es the necessary requirements to make a reliable and e ective instrument forin-situ chemical analysis. These include, the integration of a membrane interfacewith a miniaturized mass spectrometer, development of a data managementstrategy, reducing the e ects of isobaric interferences and employing an internalstandard for quantitative measurements. Furthermore, the negative e ects ofenvironmental variables, such as the Earth's magnetic eld, were examined ande ectively eliminated. In addition, this work demonstrates quantitative mapping ofatmospheric VOCs in real-time, which allows rapid identi cation of chemical plumesand therefore, areas of potential concern. Both lab and eld-based comparisons ofivmembrane introduction mass spectrometer data and traditional whole air samplingcanister data were undertaken. The primary eld site was near Ft. McMurray, ABwhere baseline data was collected around a steam assisted gravity drainage (SAGD)facility and surrounding public roads. Monitoring for fugitive emissions at thisfacility and surrounding bitumen mining and processing operations is demonstrated.Field data were also obtained, near an industrial site in Ft.Saskatchewan, AB, thatdemonstrate the e cacy of an adaptive sampling strategy. Finally, chemicalionization was investigated as a soft ionization strategy to improve chemicalselectivity for the analysis of complex hydrocarbon mixtures. The development of anin-line liquid chemical ionization reagent delivery system is presented and proposedas an e ective strategy for eliminating interferences arising from biogenic terpenesand alkyl aromatics. In all, this thesis presents the design and implementation of amobile membrane introduction mass spectrometer for atmospheric chemicalanalysis. Results that improve performance and demonstrate the novelty of thedata-type are provided, along with avenues for future development.

Download or read book Adapting a Field Deployable Noble Gas Mass Spectrometer for Continuous Measurements of Helium written by Katherine Chan and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Isotopes of the five stable noble gases (He, Ne, Ar, Kr, and Xe) are useful in analyzing physical processes in the environment such as air-sea gas exchange and sea ice formation and melting. Traditional measurements of noble gases are costly and time-consuming because of the need to transport water samples to analyze in a laboratory-based mass spectrometer. Field deployable mass spectrometers were developed as a low-cost method to increase the temporal resolution of the measurements. Our system utilizes a quadrupole mass spectrometer in tandem with a gas equilibrator cartridge to continuously measure equilibrated gases from water with ambient air as a calibration standard. The reproducibility of the system is better than 0.7% for all gas ratios in a lab environment. However, our current configuration is not optimized for measuring helium because of the high permeability of helium through many of the materials used. Nonetheless, measuring helium will yield insight into quantifying bubble processes, which significantly affects rates of air-sea gas exchange. Our mass spectrometer configuration was thus extended to measure helium by switching from fused silica capillaries to stainless steel capillaries and switching from Tygon tubing to Viton tubing. The equilibration and precision of the new system was compared to that of the old configuration. Leak tests were performed on the old and new configuration to assess whether the leakiness of the system has improved. Results showed effective measurements of He with precisions better than 0.80% for both He/Ar and He/Kr at water temperatures of 22°C and above. Further optimization is needed to improve the equilibration of He and Ne at water temperatures of 10°C.

Download or read book An Aerosol Mass Spectrometer written by James D. Allan and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of a Membrane Inlet Mass Spectrometer MIMS for Environmental Monitoring and Other Applications written by Farnoush Salarzaei and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: