A5102815121- Engineering and Material Science Research
- Engineering Applied Research
- Advanced Chemical Sensor Technologies
- Analytical Chemistry and Chromatography
- Mass Spectrometry Techniques and Applications
- Spectroscopy and Chemometric Analyses
- Analytical Chemistry and Sensors
- Target Tracking and Data Fusion in Sensor Networks
- Pesticide Residue Analysis and Safety
- Water Quality Monitoring and Analysis
- Fault Detection and Control Systems
- Insect Pheromone Research and Control
- Analytical chemistry methods development
- Distributed Sensor Networks and Detection Algorithms
- Gas Sensing Nanomaterials and Sensors
- Ion-surface interactions and analysis
- Advanced MRI Techniques and Applications
- Water Quality Monitoring Technologies
- Chemical Thermodynamics and Molecular Structure
- Atmospheric and Environmental Gas Dynamics
- Microfluidic and Capillary Electrophoresis Applications
- Toxic Organic Pollutants Impact
- Fire Detection and Safety Systems
- Spectroscopy Techniques in Biomedical and Chemical Research
- Energetic Materials and Combustion
The University of Texas Medical Branch at Galveston
2024
United States Naval Research Laboratory
2010-2021
Stantec (Canada)
2017
K Lab (United States)
2007-2015
Dow Chemical (United States)
2001-2014
Naval Research Laboratory Chemistry Division
2006
Georgetown University
2005
Georgetown University Medical Center
2005
University of Washington
2001-2004
Louisiana State University Health Sciences Center New Orleans
2004
Solid state gas sensors are a core enabling technology to range of measurement applications including industrial, safety, and environmental monitoring. The associated with solid-state has evolved in recent years advances materials, improvements processing miniaturization. In this review, we examine the state-of-the-art solid goal understanding approaches, various sensor design methods provide targeted functionality, future prospects field. structure, detection mechanism, sensing properties...
The use of liquid fuels necessitates methods to assess the quality and suitability these for their intended use. Traditionally, this is performed through a series chemical physical tests. However, in some operational situations, streamlined reliably evaluate fuel would offer distinct advantages. Naval Research Laboratory has been engaged research program explore develop rapid automated surveillance technologies. Chemometric modeling methodologies have investigated as means derive...
Chemical detection in complex environments presents numerous challenges for successful implementation. Arrays of sensors are often implemented chemical sensing tasks, but systematic understanding how individual sensor response characteristics contribute overall system performance remains elusive, with generalized strategies design and optimization these arrays rarely reported even less commonly adopted by practitioners. This review focuses on the literature nonspecific array as well related...
Quantitative analysis of naphtha samples is demonstrated using comprehensive two-dimensional gas chromatography (GC x GC) and chemometrics. This work aimed at providing a GC system for the quantitative qualitative complex process streams monitoring control. The high-speed accomplished through short columns, high carrier velocities, partial chromatographic peak resolution followed by multivariate analysis. Six min separations are analyzed with trilinear least squares (tri-PLS) to predict...
Comprehensive, two-dimensional gas chromatography (GC x GC) is used in conjunction with trilinear partial least squares (Tri-PLS) to quantify the percent weight of naphthalenes (two-ring aromatic compounds) jet fuel samples. The increased peak capacity and selectivity GC makes technique attractive for rapid, possibly less tedious analysis fuel. complex mixtures by further enhanced through use chemometric techniques, including those designed on 2-D data such as Tri-PLS. Unfortunately,...
Post-plasma ambient desorption/ionization (ADI) sources are fundamentally dependent on surrounding water vapor to produce protonated analyte ions. There two reports of humidity effects ADI spectra. However, it is unclear whether will affect all and analytes, by what mechanism affects Flowing atmospheric pressure afterglow (FAPA) ionization direct analysis in real time (DART) mass spectra various surface-deposited gas-phase analytes were acquired at temperature across a range observed values....
Unstable explosive hexamethylene triperoxide diamine (HMTD) is dangerous in quantity and benefits from the minimal sampling handling associated with atmospheric pressure chemical ionization for mass spectral analysis. Seasonal variation observed HMTD spectra suggested a humidity dependence. Therefore, direct analysis real time (DART) were acquired at range of values. An enclosure was designed to fit around ion source spectrometer inlet pressure. The supplied controlled amounts humidified air...
In this work, a set of 45 fuel samples from around the world was acquired, with complete compositional and specification test results. These were analyzed by near-infrared (NIR) spectrophotometry, Raman spectroscopy, gas chromatography mass selective detection (GC−MS). The measured NIR, Raman, GC−MS data evaluated for their ability to predict various properties via partial least squares modeling (PLS) as part an effort directed toward developing robust, sensor-based quality assessment...
Compound Specific Isotope Analysis (CSIA) has been shown to be a useful tool for assessing biodegradation, volatilization, and hydrocarbon degradation. One major advantage of this technique is that it does not rely on determining absolute or relative abundances individual components mixture which may change considerably during weathering processes. However, attempts use isotopic values linking sources spilled otherwise unknown hydrocarbons have hampered by the lack robust rigorous...
Recent advances in the field of chemometrics have provided us with an opportunity to determine if it is possible extend numerical multivariate pattern recognition techniques beyond simple fuel characterization, identification important compositional features that are related quality. This can include unique combinations normally benign constituents exert impact on stability. Fuels ideal candidates for chemometric analysis, because we often concerned minute within a complex matrix. Two...
A set of low-sulfur diesel fuels from the Western Pacific region were found to be unstable during storage although they passed all standard specification tests. This sample was have high nitrogen content. Initially, liquid–liquid extractions with a mild aqueous acid performed separate basic and nonbasic groups in an attempt determine if these organonitrogen classes responsible for poor stability. The findings this study indicate that there may correlation between acid-extractable compounds...
Partial least-squares (PLS) was used to formulate property models for a set of 43 jet fuel samples using near-infrared (NIR), Raman, and gas chromatography (GC) data. A total 28 different properties were evaluated each technique. Given that the data small several distributions nonideal, significance testing model formulation evaluation. statistical F test applied selection latent variables, determining level compared random chance evaluating increase in prediction error when expected sources...
The opportunistic fungal pathogen Candida albicans has the ability to exploit diverse host environments and can either reside commensally or cause disease. In order adapt its new environment it must respond physical conditions, nutrient sources, immune response. This requires co-regulation of multiple signalling networks. 14-3-3 family proteins is highly conserved in all eukaryotic species. These regulate pathways involved cell survival, cycle, differentiation, effect their functions via...