Electronic Cigarettes: Truth or Toxic?

With the increasing research on the hazards of cigareDes, people are looking for a safer alterna\u3eve to smoking. Electronic CigareDes were introduced in the early 2000’s to serve this purpose, and they are gaining increasing popularity. Many e-cigareDe companies claim that the use of e-cigareDes is completely harmless because of combus\u3eon of the organic liquids would cause the inhala\u3eon of only water vapor and carbon dioxide along with the flavors and nico\u3ene. Companies also adver\u3ese their products to help smokers quit smoking. Recently, “vaping” has grown increasingly popular especially with minors since several states s\u3ell allow the sale of e-cigareDes to minors. Studies have shown that more teenagers are vaping, and that it may lead to the use of real cigareDes. In more recent news there have been reports of respiratory problems arising from e-cigareDe use, as well as the cigareDes exploding during use causing harm to the user. There are two main concerns that individuals may have concerning e-cigareDes. Most users are concerned about the compounds absorbed by the body, while non users are concerned with the compounds present in the vapors exhaled by users. To address the concerns of e-cigareDe users, the vapors were analyzed using simultaneous thermal analysis infrared spectroscopy (STA-IR) and the results indicate that the vapors released aUer hea\u3eng are not simply carbon dioxide and water, so the liquids do not undergo combus\u3eon and may not be as harmless as claimed by ecigareDe companies. Further inves\u3ega\u3eon using gas chromatography mass spectrometry (GC-MS) is being performed to determine the compounds formed as a result of hea\u3eng the e-liquids. To address the concerns of non users, a device similar to a hookah was created to capture the vapors on clothing material (to simulate second hand smoke) before extrac\u3eng the compounds captured on the material and analyzing the chemical content in the GC-MS

Biomass estimations of invasives Yaupon, Chinese Privet and Chinese Tallow in east Texas Hardwood and Pine Ecosystems

Forest understory fuels can have profound effects on fire behavior and crown fire initiation. Accurate fire behavior prediction in understory fuels is an essential component for estimating fire intensity and severity during wildfire and prescribed fire events. This study focused on estimating temporal and seasonal changes in fuel loading parameters associated with the expansion of invasive yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), and Chinese tallow (Triadica sebifera) in East Texas pine and hardwood ecosystems. Fuel loading data of invasive species infested sites indicated significant increases in understory biomass when compared to 1988 estimates, suggesting a clear need to revise regional fuel models. Multiple and simple regression biomass prediction equations were developed for all three-invasive species to facilitate fuel load estimates. These improved prediction equations will enhance fire management efforts as well as invasive species mitigation efforts in east Texas

Initial investigation of seasonal flammability of three invasive East Texas forest understory fuels using thermogravimetric analysis

East Texas forest understory fuels have become increasingly infested with invasive species which have contributed to greater hazardous fuel loads when combined with decades of fire exclusion and passive management. This study focused on estimating seasonal changes in flammability parameters of invasive yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), and Chinese tallow (Triadica sebifera) using thermogravimetric analysis. Foliage and stem samples were collected in the dormant (February) and growing (August) seasons. Differential thermogravimetric (DTG) and proximate analyses were used to estimate species specific flammability parameters related to relative spontaneous ignition temperature (RSIT), gas-phase maximum mass loss rate (GP-MMLR), and combustion duration (GP-CD). Seasonality played a significant role among species RSIT (p\u3c0.0001) and GP-CD (p\u3c0.03). Proximate analysis VM% was relatively consistent with flammability indices, while the combination of VM% and ash% helped explain some inconsistencies. Yaupon exhibited the greatest foliage ignitability (\u3eRSIT) and combustibility (\u3eGP-MMLR) followed by Chinese privet and tallow. Consequently, yaupon poses a significant year round wildfire and fire management risk. Chinese privets’ greater dormant season ignitability may improve prescribed fire control efforts in mid-winter, but may also pose a significant wildfire risk during drought and windy conditions. Chinese tallow stems’ greater growing season flammability may enhance integrated control measures using prescribed fire in late summer and early fall. In summary, these data further local knowledge related to seasonal and relative plant flammability and may be useful as additional inputs into custom fuel models, as well as assigning flammability hazard ratings for ornamental vegetation within the wildland-urban interface

Initial investigation of seasonal flammability of three invasive East Texas forest understory fuels using thermogravimetric analysis

East Texas forest understory fuels have become increasingly infested with invasive species which have contributed to greater hazardous fuel loads when combined with decades of fire exclusion and passive management. This study focused on estimating seasonal changes in flammability parameters of invasive yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), and Chinese tallow (Triadica sebifera) using thermogravimetric analysis. Foliage and stem samples were collected in the dormant (February) and growing (August) seasons. Differential thermogravimetric (DTG) and proximate analyses were used to estimate species specific flammability parameters related to relative spontaneous ignition temperature (RSIT), gas-phase maximum mass loss rate (GP-MMLR), and combustion duration (GP-CD). Seasonality played a significant role among species RSIT (p\u3c0.0001) and GP-CD (p\u3c0.03). Proximate analysis VM% was relatively consistent with flammability indices, while the combination of VM% and ash% helped explain some inconsistencies. Yaupon exhibited the greatest foliage ignitability (\u3eRSIT) and combustibility (\u3eGP-MMLR) followed by Chinese privet and tallow. Consequently, yaupon poses a significant year round wildfire and fire management risk. Chinese privets’ greater dormant season ignitability may improve prescribed fire control efforts in mid-winter, but may also pose a significant wildfire risk during drought and windy conditions. Chinese tallow stems’ greater growing season flammability may enhance integrated control measures using prescribed fire in late summer and early fall. In summary, these data further local knowledge related to seasonal and relative plant flammability and may be useful as additional inputs into custom fuel models, as well as assigning flammability hazard ratings for ornamental vegetation within the wildland-urban interface

Dendritic Surfactants Show Evidence for Frustrated Intercalation: A New Organoclay Morphology

Mixing a smectite clay with some dendritic surfactants shows that despite the large size of some of these molecules, a property that frustrates complete intercalation into the gallery of the clay, organoclay materials are obtained. X-ray powder diffraction (XPD) reveals no significant increases in lattice spacing as these surfactants are added. Infrared (IR) spectroscopy and thermal gravimetric analysis (TGA) show that interlayer water is preserved. Consistent with an undisturbed interlayer, the amount of organic material in organoclays derived from frustrated surfactants does not exceed 15% of the cationic exchange capacity (CEC) of the composite. Smaller dendritic surfactants do not display frustrated intercalation and instead readily enter into the gallery of the smectic clay yielding traditional organoclay materials. A range of organic compositions (5-50% w/w) that exceed the CEC of the materials are observed. The organic content is corroborated by UV spectroscopy and TGA. XPD reveals increasing lattice spacings with increasing organic content. IR spectroscopy and TGA support an increasingly hydrophobic interlayer. A linear isomer of a frustrated surfactant can intercalate into the gallery (5-33% w/w) yielding morphologies that depend on the amount of surfactant added. These results support the hypothesis that shape, and not only size, is important for producing frustrated intercalation