Theodore Thaddeus Borek

Ethylene-Vinyl Acetate Potential Problems for Photovoltaic Packaging

Photovoltaic (PV) devices are typically encapsulated using ethylene-vinyl acetate (EVA) to provide mechanical support, optical coupling, electrical isolation, and protection against environmental exposure. Under exposure to atmospheric water and/or ultraviolet radiation, EVA will decompose to produce acetic acid, lowering the pH and increasing the surface corrosion rates of embedded devices. Even though acetic acid is produced at a very slow rate, it may not take much to catalyze reactions that lead to rapid module deterioration. Another consideration is that the glass transition of EVA, as measured using dynamic mechanical analysis, begins at temperatures of about -15 degC. Temperatures lower than this can be reached for extended periods of time in some climates. Because of increased moduli below the glass transition temperature, a module may be more vulnerable to damage if a mechanical load is applied by snow or wind at low temperatures. Modules using EVA should not be rated for use at such low temperatures without additional low-temperature mechanical testing beyond the scope of UL1703

An Economic Analysis of Mobile Pyrolysis for Northern New Mexico Forests

In the interest of providing an economically sensible use for the copious small-diameter wood in Northern New Mexico, an economic study is performed focused on mobile pyrolysis. Mobile pyrolysis was selected for the study because transportation costs limit the viability of a dedicated pyrolysis plant, and the relative simplicity of pyrolysis compared to other technology solutions lends itself to mobile reactor design. A bench-scale pyrolysis system was used to study the wood pyrolysis process and to obtain performance data that was otherwise unavailable under conditions theorized to be optimal given the regional problem. Pyrolysis can convert wood to three main products: fixed gases, liquid pyrolysis oil and char. The fixed gases are useful as low-quality fuel, and may have sufficient chemical energy to power a mobile system, eliminating the need for an external power source. The majority of the energy content of the pyrolysis gas is associated with carbon monoxide, followed by light hydrocarbons. The liquids are well characterized in the historical literature, and have slightly lower heating values comparable to the feedstock. They consist of water and a mix of hundreds of hydrocarbons, and are acidic. They are also unstable, increasing in viscosity with time stored. Up to 60% of the biomass in bench-scale testing was converted to liquids. Lower ({approx}550 C) furnace temperatures are preferred because of the decreased propensity for deposits and the high liquid yields. A mobile pyrolysis system would be designed with low maintenance requirements, should be able to access wilderness areas, and should not require more than one or two people to operate the system. The techno-economic analysis assesses fixed and variable costs. It suggests that the economy of scale is an important factor, as higher throughput directly leads to improved system economic viability. Labor and capital equipment are the driving factors in the viability of the system. The break-even selling price for the baseline assumption is about

Real-time discriminatory sensors for water contamination events :LDRD 52595 final report.

11/GJ, however it may be possible to reduce this value by 20-30% depending on other factors evaluated in the non-baseline scenarios. Assuming a value for the char co-product improves the analysis. Significantly lower break-even costs are possible in an international setting, as labor is the dominant production cost.

Composition of the essential oils from Rocky Mountain juniper (Juniperus scopulorum), Big sagebrush (Artemisia tridentata), and White Sage (Salvia apiana).

The gas-phase {mu}ChemLab{trademark} developed by Sandia can detect volatile organics and semi-volatiles organics via gas phase sampling . The goal of this three year Laboratory Directed Research and Development (LDRD) project was to adapt the components and concepts used by the {mu}ChemLab{trademark} system towards the analysis of water-borne chemicals of current concern. In essence, interfacing the gas-phase {mu}ChemLab{trademark} with water to bring the significant prior investment of Sandia and the advantages of microfabrication and portable analysis to a whole new world of important analytes. These include both chemical weapons agents and their hydrolysis products and disinfection by-products such as Trihalomethanes (THMs) and haloacetic acids (HAAs). THMs and HAAs are currently regulated by EPA due to health issues, yet water utilities do not have rapid on-site methods of detection that would allow them to adjust their processes quickly; protecting consumers, meeting water quality standards, and obeying regulations more easily and with greater confidence. This report documents the results, unique hardware and devices, and methods designed during the project toward the goal stated above. It also presents and discusses the portable field system to measure THMs developed in the course of this project.

6-Chloro-2,4-bis-(dimethyl-amino)-1,3,5-trimethyl-borazine.

The essential oils of Juniperus scopulorum, Artemisia tridentata, and Salvia apiana obtained by steam extraction were analyzed by GC-MS and GC-FID. For J. scopulorum, twenty-five compounds were identified which accounts for 92.43% of the oil. The primary constituents were sabinene (49.91%), {alpha}-terpinene (9.95%), and 4-terpineol (6.79%). For A. tridentata, twenty compounds were identified which accounts for 84.32% of the oil. The primary constituents were camphor (28.63%), camphene (16.88%), and 1,8-cineole (13.23%). For S. apiana, fourteen compounds were identified which accounts for 96.76% of the oil. The primary component was 1,8-cineole (60.65%).

2,4-Bis(dimethyl­amino)-1,3,5-trimethyl-6-(nitro­oxy)borazine

The borazine ring of the title molecule, C7H21B3ClN5, shows a mild distortion from a planar to a flattened boat conformation. Steric effects due to the methyl and dimethylamine substituents appear to be the cause of this distortion.

Bench-Scale Pyrolysis of Wood Pellets

In the title compound, C7H21B3N6O3, the r.m.s. deviation of the borazine ring atoms is 0.019 Å. The dimethylamino groups are orientated at 41.80 (7) and 36.43 (7)° with respect to the borazine ring. The nitrooxy group is almost normal to the borazine ring [dihedral angle = 85.33 (14)°]. The methyl C atom trans to the NO3 group is displaced by −0.512 (3) Å from the ring plane, whereas the two ortho-methyl C atoms are displaced by 0.239 (3) and 0.178 (3) Å.

Final Report: Multicomponent Forensic Signature Development: Interactions with Common Textiles; Mustard Precursors and Simulants

Past work has demonstrated the feasibility of pyrolyzing biomass and condensing the resulting vapor to form a low quality combustible liquid. The product, often termed pyrolysis oil, bio-oil, or bio-crude, can be refined to a transportation grade fuel. Because the pyrolysis process is comparatively simple, we speculate that a mobile pyrolysis system might be able to process the biomass at the site of harvest, generating a dense liquid for transportation. This would be expected to result in improved transportation economics compared to transporting the raw biomass fuel. This technology is being considered for northern New Mexico forests that are presently managed by periodic thinning efforts with little utilization of the products. We have designed a bench-scale system and pyrolyzed biomass pellets, which function in these tests as surrogate material for the forest trimmings. The system features controllable furnace temperatures, augur feed, gas recirculation, and multi-stage condensation. We have analyzed gases, chars, and liquids resulting from various operating conditions and report product quantities and qualities through various standard chemical methods. Good liquid mass yields of over 50% of the original material are typically found, with varying product quality and quantity depending on the operating temperature. Our results suggest the current configuration gives better yields and functions more optimally at pyrolysis temperatures around 525°C. For a practical system, combustion of the non-condensable fuel gases may be able to replace the electrically heated furnace used in these tests.Copyright

Analysis of Modern and Ancient Artifacts for the Presence of Corn Beer; Dynamic Headspace Testing of Pottery Sherds from Mexico and New Mexico

2-Chloroethyl phenyl sulfide (CEPS), a surrogate compound of the chemical warfare agent sulfur mustard, was examined using thermal desorption coupled gas chromatography-mass spectrometry (TD/GC-MS) and multivariate analysis. This work describes a novel method of producing multiway data using a stepped thermal desorption. Various multivariate analysis schemes were employed to analyze the data. These methods may be able to discern different sources of CEPS. In addition, CEPS was applied to cotton, nylon, polyester, and silk swatches. These swatches were placed in controlled humidity chambers maintained at 23%, 56%, and 85% relative humidity. At regular intervals, samples were removed from each test swatch, and the samples analyzed using TD/GC-MS. The results were compared across fabric substrate and humidity.

Research into the variables affecting purge and trap collection for a portable field trihalomethane testing unit.

A large volume-headspace apparatus that permits the heating of pottery fragments for direct analysis by gas chromatography/mass spectrometry is described here. A series of fermented-corn beverages were produced in modern clay pots and the pots were sampled to develop organic-species profiles for comparison with fragments of ancient pottery. Brewing pots from the Tarahumara of northern Mexico, a tribe that regularly uses corn kernels to ferment a weak beer, were also examined for volatile residues and organic-species profiles were generated. Finally, organic species were generated from ancient potsherds from an archaeological site and compared with the modern spectra. The datasets yielded similar organic species, many of which were identified by computer matching of the resulting mass spectra with the NIST mass spectral library. Additional analyses are now underway to highlight patterns of organic species common to all the spectra. This presentation demonstrates the utility of GC/MS for detecting fermentation residues in the fabric of unglazed archaeological ceramics after centuries of burial. This, in turn, opens unexpected new doors for understanding the human past by means of GC/MS analyses.