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Sample records for polyolefin hazy film

  1. Porous Polyolefin Films via Polymer Blends

    NASA Astrophysics Data System (ADS)

    Macosko, Chris

    Porous polymer films have broad application including battery separators, membrane supports and filters. Polyolefins are attractive for these applications because of their solvent resistance, low electrical and thermal conductivity, easy fabrication and cost. We will describe fabrication of porous films using cocontinuous blends of a polyolefin with another polymer which can be readily removed with a solvent. Methods to image and control the cocontinuous morphology will be presented.Bell, J. R., K. Chang, C. R. Lopez-Barron, C. W. Macosko, and D. C. Morse, ''Annealing of cocontinuous polymer blends: effect of block copolymer molecular weight and architecture,'' Macromolecules 43, 5024-5032 (2010).Lopez-Barron, C. R., and C. W. Macosko, ''Direct measurement of interface anisotropy of bicontinuous structures via 3D image analysis,'' Langmuir 26, 14284-14293 (2010).Trifkovic, M., A. T. Hedegaard, K. Huston, M. Sheikhzadeh, and C. W. Macosko, ''Porous films via PE/PEO cocontinuous blends,'' Macromolecules 45, 6036-6044 (2012).Hedegaard, A.T., L.L. Gu and C. W. Macosko, ``Effect of Extensional Viscosity on Cocontinuity of Immiscible Polymer Blends'' J. Rheol. 59, 1397-1417 (2015).

  2. Nanocomposite fibers and film containing polyolefin and surface-modified carbon nanotubes

    SciTech Connect

    Chu,Benjamin; Hsiao, Benjamin S.

    2010-01-26

    Methods for modifying carbon nanotubes with organic compounds are disclosed. The modified carbon nanotubes have enhanced compatibility with polyolefins. Nanocomposites of the organo-modified carbon nanotubes and polyolefins can be used to produce both fibers and films having enhanced mechanical and electrical properties, especially the elongation-to-break ratio and the toughness of the fibers and/or films.

  3. 21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Resinous and polymeric coatings for polyolefin films. 175.320 Section 175.320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS OF COATINGS Substances for Use...

  4. 21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Resinous and polymeric coatings for polyolefin films. 175.320 Section 175.320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS OF COATINGS Substances for Use as Components of Coatings § 175.320...

  5. 21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Resinous and polymeric coatings for polyolefin films. 175.320 Section 175.320 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADHESIVES AND COMPONENTS OF COATINGS Substances for Use...

  6. Polyolefin-based aerogels

    NASA Technical Reports Server (NTRS)

    Lee, Je Kyun (Inventor); Gould, Gerogle L. (Inventor)

    2010-01-01

    The present invention relates to cross-linked polyolefin aerogels in simple and fiber-reinforced composite form. Of particular interest are polybutadiene aerogels. Especially aerogels derived from polybutadienes functionalized with anhydrides, amines, hydroxyls, thiols, epoxies, isocyanates or combinations thereof.

  7. Hazy Archean Earth as an Analog for Hazy Earthlike Exoplanets

    NASA Astrophysics Data System (ADS)

    Arney, Giada; Meadows, Victoria; Domagal-Goldman, Shawn; Claire, Mark; Schwieterman, Edward

    2015-01-01

    Hazy exoplanets may be common (Bean et al. 2010, Sing et al. 2011, Kreidberg et al 2014), and in our solar system, Venus and Titan have photochemically-produced hazes. There is evidence that Earth itself had a hydrocarbon haze in the Archean (Zerkle et al. 2012, Domagal-Goldman et al. 2008) with important climatic effects (Pavlov et al. 2001, Trainer et al. 2006, Haqq-Misra et al. 2008, Wolf and Toon 2012). We use a 1D coupled photochemical-climate model and a line-by-line radiative transfer model to investigate the climactic and spectral impacts of a fractal hydrocarbon haze on Archean Earth. The haze absorbs significantly at shorter wavelengths and can strongly suppress the Rayleigh scattering tail, a broadband effect that would be remotely detectable at low spectral resolution at wavelengths less than 0.5 μm. Hazes may have a more significant impact on transit transmission spectra. Using the transit transmission radiative transfer model developed by Misra et al. (2014) to generate hazy Archean spectra, we find that even a thin hydrocarbon haze masks the lower atmosphere from the visible into the near infrared where the haze optical depth exceeds unity. The transit transmission spectra we generate for hazy Archean Earth are steeply sloped like the Titan solar occultation spectrum observed by Robinson et al. (2014). Thick hazes can also cool the planet significantly: for example, the thick fractal haze generated around Archean Earth with 0.3% CH4, 1% CO2 and 1 ppm C2H6 cools the planet from roughly 290 K without the haze to below freezing with the haze. Finally, we investigate the impact of host star spectral type on haze formation, comparing the hazes generated around a solar-type star to those generated at an Earth analog planet around the M dwarf AD Leo. Our results indicate hazes around M dwarfs for the same initial atmospheric composition may be thinner due to decreased UV photolysis of methane and other hydrocarbons needed for haze formation. Earthlike

  8. Polyolefin catalyst manufacturing

    SciTech Connect

    Inkrott, K.E.; Scinta, J.; Smith, P.D. )

    1989-10-16

    Statistical process control (SPC) procedures are absolutely essential for making new-generation polyolefin catalysts with the consistent high quality required by modern polyolefin processes. Stringent quality assurance is critical to the production of today's high-performance catalysts. Research and development efforts during the last 20 years have led to major technological improvements in the polyolefin industry. New generation catalysts, which once were laboratory curiosities, must now be produced commercially on a regular and consistent basis to meet the increasing requirements of the plastics manufacturing industry. To illustrate the more stringent requirements for producing the new generation polyolefin catalysts, the authors compare the relatively simple, first-generation polypropylene catalyst production requirements with some of the basic requirements of manufacturing a more complex new-generation catalyst, such as Catalyst Resources Inc.'s LYNX 900. The principles which hold true for the new-generation catalysts such as LYNX 900 are shown to apply equally to the scale-up of other advanced technology polyolefin catalysts.

  9. Polyolefins as additives in plastics

    SciTech Connect

    Deanin, R.D.

    1993-12-31

    Polyolefins are not only major commodity plastics - they are also very useful as additives, both in other polyolefins and also in other types of plastics. This review covers ethylene, propylene, butylene and isobutylene polymers, in blends with each other, and as additives to natural rubber, styrene/butadiene rubber, polystyrene, polyvinyl chloride, polymethyl methacrylate, polyphenylene oxide, polycarbonate, thermoplastic polyesters, polyurethanes, polyamides, and mixed automotive plastics recycling.

  10. Polyolefin composites containing a phase change material

    DOEpatents

    Salyer, Ival O.

    1991-01-01

    A composite useful in thermal energy storage, said composite being formed of a polyolefin matrix having a phase change material such as a crystalline alkyl hydrocarbon incorporated therein, said polyolefin being thermally form stable; the composite is useful in forming pellets, sheets or fibers having thermal energy storage characteristics; methods for forming the composite are also disclosed.

  11. A Hazy Day in Mexico City

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Mexico City has one of the world's most serious air pollution problems. The city is located atop a high plain at an altitude of 2200 meters, and is surrounded on three sides by mountains and snow-capped volcanoes. Since incident solar radiation does not vary significantly with season at tropical latitudes, photochemical smog is produced much of the year. In winter, air quality can worsen significantly when thermal inversions keep polluted air masses close to the surface.

    Atmospheric particulates (aerosols) are readily visible at oblique view angles, and differences in aerosol amount on two days are indicated by these images of central Mexico from the Multi-angle Imaging SpectroRadiometer (MISR). The images at left and center are natural color views acquired by MISR's 70-degree forward-viewing camera on April 9 and December 5, 2001, respectively. Mexico City can be identified in the center panel by the large area of haze accumulation above image center. Two small brighter patches within the hazy area indicate low fog. In the left-hand panel, the city basin appears significantly clearer, but some haze remains apparent across the Sierra Madre mountains in the lower portion of the images. On the right is an elevation field corresponding to the December 5 view. Automated MISR stereoscopic retrievals reveal the clouds at lower right to be at very high altitudes, in contrast to the low-lying haze and fog near Mexico City. When the stereo retrieval determines that a location is not covered by clouds, digital terrain elevation data are displayed instead. High clouds appear as the orange and red areas, and mountainous areas appear light blue and green. The position of the clouds within the 70-degree image are slightly southward of their location in the elevation map as a consequence of geometric parallax.

    Major sources of air pollutants within the basin enclosing the Mexico City urban area include exhaust from 3.5 million vehicles, thousands of industries, and

  12. Pale Orange Dots: Hazy Archean Earth as an Analog for Hazy Earthlike Exoplanets

    NASA Astrophysics Data System (ADS)

    Arney, Giada; Domagal-Goldman, Shawn; Meadows, Victoria S.; Claire, Mark; Schwieterman, Edward

    2014-11-01

    Of the four terrestrial worlds with significant atmospheres in our solar system - Venus, Earth, Mars, and Titan - two of these worlds are presently enshrouded by hazes, and observations suggest that hazy exoplanets are also common (Bean et al. 2010, Sing et al. 2011, Kreidberg et al 2014, Knutson et al. 2014). The early (Archean) Earth may have had a photochemical hydrocarbon haze similar to Titan's (Zerkle et al. 2012), with important climactic effects (Pavlov et al. 2001, Trainer et al. 2006, Haqq-Misra et al. 2008, Domagal-Goldman et al. 2008, Wolf and Toon 2012). Here, we considered Archean Earth as an analog for hazy Earthlike exoplanets and used a modified version of the 1-D photochemical code developed originally by Kasting et al. (1979) to generate model Archean atmospheres with fractal hydrocarbon haze particles. A 1-D line-by-line fully multiple scattering radiative transfer model (Meadows and Crisp 1996) was then used to generate synthetic spectra of early Earth with haze. We have used the resulting synthetic spectra to examine the effect of haze on the detectability of putative biosignatures and the Rayleigh scattering slope, which has been suggested as a means for constraining atmospheric pressure (Benneke and Seager 2012). We also examined haze's impact on the spectral energy distribution reaching the planetary surface. Because the atmospheric pressure and haze particle composition of the Archean Earth are poorly constrained, and because exoplanets will occupy a range of parameter space, we tested the influence of atmospheric pressure and particle density on haze formation, and explored how various particle size distributions affect the spectrum. We find that haze strongly affects the spectral region of the Rayleigh slope, a change detectable at low spectral resolution that impacts the ability to constrain pressure with Rayleigh scattering. The spectral energy distribution at the surface is modulated by haze thickness and the assumed particle size

  13. Polyolefins to thrive by 1995

    SciTech Connect

    Morris, G.D.L.

    1993-03-03

    Five factors will shorten the [current] period of distress for global polyolefins producers, says George T. Scott, v.p. and general manager of olefins and derivatives for Chevron Chemical (Houston): lower feedstock costs, the weaker dollar, higher operating rates, higher converter capacity, and technical improvements at the high end of the market. The next two years will be tough, says Scott, but I am hopeful of a full recovery to reinvestment economics by 1995. Scott made his remarks in the keynote address last week at a technical conference in Houston sponsored by the Society of Plastics Engineers (Brookfield, IL). Of the five factors, lower feedstock costs are the most immediate, with ethylene, and especially propylene, mired in neart-term record lows. However, other market watchers point out that the upstream situation must now include cracker feedslates because more merchant polyolefin producers are integrated back to the monomer. With as little as one-quarter of polymer capacity supplied from the merchant olefin market, by some estimates, a dollars/1,000-cubic-feet number is now more important than a cents/pound number. Technical advances at the top of the market are another intriguing factor. In recent years, says Scott, improvements in catalysts and processes have improved operating efficiencies and costs for high-volume trains. The cutting edge work today, however, is for speciality grades and custom-designed molecules for specific applications. Such advances have the double benefit of bringing high margin materials into the market while not adding many new pounds to an oversupplied business.

  14. Ultrahigh mobility in polyolefin-supported graphene

    NASA Astrophysics Data System (ADS)

    Hsieh, Ya-Ping; Kuo, Chin-Lun; Hofmann, Mario

    2016-01-01

    A high carrier mobility is an important parameter for graphene-based electronics. While the recent reports have shown impressive results for individual micro-scale devices, scalable production of high mobility graphene has been challenging. We here show that centimeter-scale graphene devices with room temperature carrier mobilities in excess of 10 000 cm2 V-1 s-1 can be achieved on polyolefinic substrates. Measurements on Parafilm-supported graphene devices show, on average, a fivefold-enhancement in mobility over traditional devices. We find that a decreased charged-impurity scattering is the origin of this behavior. Spectroscopic characterization reveals oxygen-containing polymer residue as the main source of such charged impurities. A comparison of different polyolefins highlights the positive impact of oxygen-free polymers as support materials for high mobility graphene devices. Finally, moldable and wearable graphene devices for biosensors were shown to be enabled by polyolefinic substrates.A high carrier mobility is an important parameter for graphene-based electronics. While the recent reports have shown impressive results for individual micro-scale devices, scalable production of high mobility graphene has been challenging. We here show that centimeter-scale graphene devices with room temperature carrier mobilities in excess of 10 000 cm2 V-1 s-1 can be achieved on polyolefinic substrates. Measurements on Parafilm-supported graphene devices show, on average, a fivefold-enhancement in mobility over traditional devices. We find that a decreased charged-impurity scattering is the origin of this behavior. Spectroscopic characterization reveals oxygen-containing polymer residue as the main source of such charged impurities. A comparison of different polyolefins highlights the positive impact of oxygen-free polymers as support materials for high mobility graphene devices. Finally, moldable and wearable graphene devices for biosensors were shown to be enabled by

  15. A Retina Inspired Model for Enhancing Visibility of Hazy Images

    PubMed Central

    Zhang, Xian-Shi; Gao, Shao-Bing; Li, Chao-Yi; Li, Yong-Jie

    2015-01-01

    The mammalian retina seems far smarter than scientists have believed so far. Inspired by the visual processing mechanisms in the retina, from the layer of photoreceptors to the layer of retinal ganglion cells (RGCs), we propose a computational model for haze removal from a single input image, which is an important issue in the field of image enhancement. In particular, the bipolar cells serve to roughly remove the low-frequency of haze, and the amacrine cells modulate the output of cone bipolar cells to compensate the loss of details by increasing the image contrast. Then the RGCs with disinhibitory receptive field surround refine the local haze removal as well as the image detail enhancement. Results on a variety of real-world and synthetic hazy images show that the proposed model yields results comparative to or even better than the state-of-the-art methods, having the advantage of simultaneous dehazing and enhancing of single hazy image with simple and straightforward implementation. PMID:26733857

  16. Theory and MD Simulation of Polyolefin Blends

    NASA Astrophysics Data System (ADS)

    Curro, John G.; Grest, Gary S.; Jaramillo, Eugenio; Wu, David T.; Li, Huimin

    2004-03-01

    Molecular dynamics (MD) simulations and PRISM theory calculations were carried out on various polyolefin homopolymer and copolymer blends. These polyolefins were modeled at the united atom level at 453K using the TRaPPE potential between pairs of sites. The chi parameters from the simulations were estimated from the structure factors using the random phase approximation (RPA) in analogy with neutron scattering (SANS) experiments. The heats of mixing were computed from both simulation and PRISM theory. The MD simulations predicted temperature dependent chi parameters in good agreement with SANS measurements previously reported on hhPP/PIB, hhPP/PP, and hhPP/PE. PRISM theory calculations on the PE(x)PEE(1-x)/PP blend suggest a miscibility window for a range of copolymer compositions x in agreement with SANS experiments.

  17. Low-temperature relaxations in amorphous polyolefins

    NASA Technical Reports Server (NTRS)

    Hiltner, A.; Baer, E.; Martin, J. R.; Gillham, J. K.

    1974-01-01

    The dynamic mechanical relaxation behavior of two series of amorphous polyolefins, was investigated from 4.2 K to the glass transition. Most of the polymers show a damping maximum or plateau in the 40 to 50 K region. Various mechanisms which have been suggested for cryogenic relaxations in amorphous polymers are considered as they might relate to the polyolefins. Two secondary relaxation processes above 80 K are distinguished. A relaxation at about 160 K (beta) in the second and third member of each series is associated with restricted blackbone motion. This process requires a certain degree of chain flexibility since it is not observed in the first member of each series. A lower temperature process (gamma) is observed in each member of the second series and is attributed to motion of the ethyl side group.

  18. Titan Reveals Transit Spectra of a Definitively Hazy World

    NASA Astrophysics Data System (ADS)

    Robinson, Tyler D.; Maltagliati, Luca; Marley, Mark S.; Fortney, Jonathan J.

    2014-11-01

    Hazes dramatically influence exoplanet observations by obscuring deeper atmospheric layers. This effect is especially pronounced in transit spectroscopy, which probes large pathlengths through an exoplanet atmosphere as it crosses the disk of its host star. While hazes are proposed to explain observed featureless transit spectra, it is difficult to make inferences from the observations because of the need to disentangle effects of noise, gas absorption, and haze extinction. Here, we turn to Titan, an extremely well studied world with a hazy atmosphere, to better understand how high altitude hazes can impact exoplanet transit observations. We use solar occultation observations from the Visual and Infrared Mapping Spectrometer (VIMS) aboard NASA's Cassini spacecraft to generate transit spectra. Our approach exploits symmetry between occultations and transits, producing transit radius spectra that inherently include the effects of haze multiple scattering, refraction, and gas absorption. The data, which span 0.88-5 microns at a resolution of 12-18 nm, show strong methane absorption features, and weaker features due to other gases, including acetylene and carbon monoxide. Unlike the usual assumption made when modeling and interpreting transit observations of potentially hazy worlds, the slope set by haze in our spectra is neither flat nor has a pure Rayleigh slope, and creates a variation in transit height whose magnitude is comparable to those from the strongest gaseous absorption features. We use a simple model of haze extinction to explore how Titan's haze affects its transit spectrum, and demonstrate how high altitude hazes can severely limit the atmospheric depths probed by transit spectra, bounding our observations to pressures smaller than 0.1-10 mbar, depending on wavelength. Overall, these new data challenge our understanding of how hazes influence exoplanet transit observations, and provide a means of testing proposed approaches for exoplanet characterization

  19. Transit Spectra of a Hazy World Revealed by Titan

    NASA Astrophysics Data System (ADS)

    Robinson, Tyler D.; Maltagliati, Luca; Marley, Mark S.

    2015-01-01

    Hazes dramatically influence exoplanet observations by obscuring deeper atmospheric layers. This effect is especially pronounced in transit spectroscopy, which probes large pathlengths through an exoplanet atmosphere as it crosses the disk of its host star. While hazes are proposed to explain observed featureless transit spectra, it is difficult to make inferences from the observations because of the need to disentangle effects of noise, gas absorption, and haze extinction. Here, we turn to Titan, an extremely well studied world with a hazy atmosphere, to better understand how high altitude hazes can impact exoplanet transit observations. We use solar occultation observations from the Visual and Infrared Mapping Spectrometer (VIMS) aboard NASA's Cassini spacecraft to generate transit spectra. Our approach exploits symmetry between occultations and transits, producing transit radius spectra that inherently include the effects of haze multiple scattering, refraction, and gas absorption. The data, which span 0.88-5 microns at a resolution of 12-18 nm, show strong methane absorption features, and weaker features due to other gases, including acetylene and carbon monoxide. Unlike the usual assumption made when modeling and interpreting transit observations of potentially hazy worlds, the slope set by haze in our spectra is not flat, and creates a variation in transit height whose magnitude is comparable to those from the strongest gaseous absorption features. We use a simple model of haze extinction to explore how Titan's haze affects its transit spectrum, and demonstrate how high altitude hazes can severely limit the atmospheric depths probed by transit spectra, bounding our observations to pressures smaller than 0.1-10 mbar, depending on wavelength. Overall, these new data challenge our understanding of how hazes influence exoplanet transit observations, and provide a means of testing proposed approaches for exoplanet characterization. Additionally, our findings will

  20. 40 CFR 721.7375 - Potassium salt of polyolefin acid.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Potassium salt of polyolefin acid. 721... Substances § 721.7375 Potassium salt of polyolefin acid. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a potassium salt of...

  1. 40 CFR 721.7375 - Potassium salt of polyolefin acid.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Potassium salt of polyolefin acid. 721... Substances § 721.7375 Potassium salt of polyolefin acid. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a potassium salt of...

  2. 40 CFR 721.7375 - Potassium salt of polyolefin acid.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Potassium salt of polyolefin acid. 721... Substances § 721.7375 Potassium salt of polyolefin acid. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a potassium salt of...

  3. 40 CFR 721.7375 - Potassium salt of polyolefin acid.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Potassium salt of polyolefin acid. 721... Substances § 721.7375 Potassium salt of polyolefin acid. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a potassium salt of...

  4. 40 CFR 721.7375 - Potassium salt of polyolefin acid.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Potassium salt of polyolefin acid. 721... Substances § 721.7375 Potassium salt of polyolefin acid. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as a potassium salt of...

  5. Upgrading mixed polyolefin waste with magnetic density separation.

    PubMed

    Bakker, E J; Rem, P C; Fraunholcz, N

    2009-05-01

    Polyolefin fractions are often end fractions resulting from the recycling of end-of-life consumer products. Polypropylene (PP) and polyethylene (PE) are present in such fractions as a mixture. For instance, the ratio of PP and PE in car scrap is 70:30 on average. However, the grade of the PP and PE should typically be better than 97% to be reused again as a high quality product. Density separation of the different polyolefins can be a solution. A promising separation technique is the inverse magnetic density separator (IMDS). This paper discusses the potential of shredder residue, one of the possible polyolefin's waste stream sources for the IMDS, in detail. Experiments with the separation of polyolefins with an IMDS prototype show both high grade and high recovery. The paper concludes with the economic opportunities of the IMDS in the recycling of polyolefins. PMID:19128952

  6. Aerosol retrieval in hazy atmosphere by using polarization and radiance

    NASA Astrophysics Data System (ADS)

    Mukai, S.; Sano, I.; Nakata, M.

    2014-12-01

    Aerosol retrieval is achieved by radiative transfer simulation in the Earth atmosphere model. This work intends to propose an algorithm for multiple light scattering simulations in the hazy polarized radiation field. We have already solved the scalar radiative transfer problem in the case of haze episodes with dense concentrations of atmospheric aerosols by the method of successive order of scattering, which is named scalar-MSOS. The term "scalar" indicates radiance alone in the treatment of radiative transfer problem against "vector" involving polarized radiation field. The satellite polarimetric sensor POLDER-1, 2, 3 has shown that the spectro-photopolarimetry of terrestrial atmosphere is very useful for observation of the Earth, especially for aerosols. JAXA has been developing the new Earth observing system, GCOM satellite. GCOM-C will board the polarimetric sensor SGLI in 2017. It is highly likely that large-scale aerosol episodes will continue to occur, because the air pollution becomes to be severe due to both the increasing emissions of the anthropogenic aerosols and the complicated behavior of natural aerosols. Then many potential applications for the kind of radiation simulation by MSOS considering the polarization information denoted by Stokes parameters (I, Q, U, V), named vector-MSOS, are desired. It is shown here that dense aerosol episodes can be well simulated by a semi-infinite radiation model composed of the proposed aerosol models. In addition our vector-MSOS is examined in practice by combination use of PARASOL/POLDER, GOSAT/CAI and Aqua/MODIS data.

  7. Single-sited catalysis leads next polyolefin generation

    SciTech Connect

    Montagna, A.A.; Floyd, J.C. )

    1994-03-01

    New catalyst families are broadening product opportunities for polyolefins. An updated catalyst system, metallocene, has entered the technology race. This catalyst offers single-site activity, which narrows molecular weight and gives molecular weight distribution control for ethylene and propylene-based polymers. A comparative history details how metallocene-based polymers stack up to conventional Ziegler-Natta catalyst-produced resins. In the 1990s, catalytic and reaction-engineering developments will change polyolefin production. The pros and cons for each catalyst-based system must be examined by potential licensors before setting their product course. The paper discusses the history of polyolefin technologies, characteristics of polyolefins, new species of catalysts, comparison of old and new catalysts, low-density polymers, new comonomers, other polymer options, end user concerns, costs, and future developments.

  8. Discriminating between Cloudy, Hazy, and Clear Sky Exoplanets Using Refraction

    NASA Astrophysics Data System (ADS)

    Misra, Amit K.; Meadows, Victoria S.

    2014-11-01

    We propose a method to distinguish between cloudy, hazy, and clear sky (free of clouds and hazes) exoplanet atmospheres that could be applicable to upcoming large aperture space- and ground-based telescopes such as the James Webb Space Telescope (JWST) and the European Extremely Large Telescope (E-ELT). These facilities will be powerful tools for characterizing transiting exoplanets, but only after a considerable amount of telescope time is devoted to a single planet. A technique that could provide a relatively rapid means of identifying haze-free targets (which may be more valuable targets for characterization) could potentially increase the science return for these telescopes. Our proposed method utilizes broadband observations of refracted light in the out-of-transit spectrum. Light refracted through an exoplanet atmosphere can lead to an increase of flux prior to ingress and subsequent to egress. Because this light is transmitted at pressures greater than those for typical cloud and haze layers, the detection of refracted light could indicate a cloud- or haze-free atmosphere. A detection of refracted light could be accomplished in <10 hr for Jovian exoplanets with JWST and <5 hr for super-Earths/mini-Neptunes with E-ELT. We find that this technique is most effective for planets with equilibrium temperatures between 200 and 500 K, which may include potentially habitable planets. A detection of refracted light for a potentially habitable planet would strongly suggest the planet was free of a global cloud or haze layer, and therefore a promising candidate for follow-up observations.

  9. DISCRIMINATING BETWEEN CLOUDY, HAZY, AND CLEAR SKY EXOPLANETS USING REFRACTION

    SciTech Connect

    Misra, Amit K.; Meadows, Victoria S.

    2014-11-01

    We propose a method to distinguish between cloudy, hazy, and clear sky (free of clouds and hazes) exoplanet atmospheres that could be applicable to upcoming large aperture space- and ground-based telescopes such as the James Webb Space Telescope (JWST) and the European Extremely Large Telescope (E-ELT). These facilities will be powerful tools for characterizing transiting exoplanets, but only after a considerable amount of telescope time is devoted to a single planet. A technique that could provide a relatively rapid means of identifying haze-free targets (which may be more valuable targets for characterization) could potentially increase the science return for these telescopes. Our proposed method utilizes broadband observations of refracted light in the out-of-transit spectrum. Light refracted through an exoplanet atmosphere can lead to an increase of flux prior to ingress and subsequent to egress. Because this light is transmitted at pressures greater than those for typical cloud and haze layers, the detection of refracted light could indicate a cloud- or haze-free atmosphere. A detection of refracted light could be accomplished in <10 hr for Jovian exoplanets with JWST and <5 hr for super-Earths/mini-Neptunes with E-ELT. We find that this technique is most effective for planets with equilibrium temperatures between 200 and 500 K, which may include potentially habitable planets. A detection of refracted light for a potentially habitable planet would strongly suggest the planet was free of a global cloud or haze layer, and therefore a promising candidate for follow-up observations.

  10. Modeling neutron scattering in disperse, nonuniformly labeled commercial polyolefins

    NASA Astrophysics Data System (ADS)

    Habersberger, Brian; Hart, Kyle; Gillespie, David; Huang, Tianzi

    In spite of their chemically simple monomer elements, understanding of many structural, thermodynamic, and other aspects of polyolefins has remained elusive. Scattering studies on polyolefins are challenged by their nearly identical density in the melt, requiring the use of deuterium-labeling to provide contrast for small-angle neutron scattering (SANS). Until recently, labeling of commercial polyolefins has been prohibitively costly, leading SANS investigations on polyolefins to focus on non-disperse model systems. Commercial polyolefins often have broad molecular weight and composition distributions, and such dispersity plays an important role in their rheology, crystallization, and mechanical properties. Recent reports have described facile hydrogen-deuterium exchange reactions that preserve the chain architecture of polyolefins. However, such exchange is not uniformly distributed across the chain population. Here, we report a generalized application of the Random Phase Approximation prediction for SANS from homogeneous polymer blends to account for such dispersity. A Monte-Carlo method is used to calculate the deuterium distribution that corresponds to SANS measurements. These methods provide powerful tools for probing the structure of disperse polymer architectures.

  11. Concentration and size distribution of total airborne microbes in hazy and foggy weather.

    PubMed

    Dong, Lijie; Qi, Jianhua; Shao, Congcong; Zhong, Xi; Gao, Dongmei; Cao, Wanwan; Gao, Jiawei; Bai, Ran; Long, Gaoyuan; Chu, Congcong

    2016-01-15

    Atmospheric bioaerosol particles were collected using a bioaerosol sampler from Oct. 2013 to Aug. 2014 in the coastal region of Qingdao. The total microbes were measured using an epifluorescence microscope after staining with DAPI (4',6-diamidino-2-phenylindole). The concentration of total airborne microbes showed seasonal variation, with the highest value in winter and the lowest in summer. The mean concentration of total microbes was 6.55 × 10(5)Cells/m(3) on non-hazy days. The total microbe concentration increased to 7.09 × 10(5) and 9.00 × 10(5)Cells/m(3) on hazy and foggy days, respectively. The particle sizes of the total microbes presented a bimodal distribution on sunny days, with one peak at 1.1-2.1 μm and another at 4.7-7.0 μm. The size distribution of total microbes showed an increase in the fine fraction on hazy days and an increase in the coarse fraction on foggy days. However, the size distribution became unimodal during a heating period. Spearman correlation analysis showed that temperature and O3 had a significant negative correlation with the airborne microbe concentration, while PM2.5, SO2, NO2, CO and the air quality index (AQI) had significant positive correlations with the airborne microbe concentration during hazy days. The increased number of airborne microbes will affect the air quality on hazy days. PMID:26473703

  12. Thermoplastic polyurethane (TPU)/polyolefin (PO) blends

    NASA Astrophysics Data System (ADS)

    Lu, Qiwei

    Thermoplastic polyurethane (TPU) is a very important material with high versatility and superior physical properties. Melt blending TPU with metallocene polyolefin (PO) can lower TPU cost and improve polyolefin properties like abrasion resistance, adhesion, and paintability. Since TPU and non-polar PO blends are completely immiscible, efficient compatibilizers become the key issue and remain challenging. My main thesis work is to develop and study compatibilized TPU/PO blends. Although reactive compatibilization is considered the most efficient method, fast interfacial reactions between highly reactive functional groups are necessary to generate compatibilizers within usually short processing time. It is known that the urethane linkage (carbamate -NHCOO-) in TPU can reversibly dissociate to generate highly reactive isocyanates at melt temperatures. To find out the best reactive compatibilization, three approaches were employed on different molecular scales: (1) model urethane compound (dibutyl & dioctyl 4,4'-methylenebis(phenyl carbamate)) and small functional molecule (primary amine, secondary amine, hydroxyl, acid, anhydride, and epoxide) reactions at 200°C monitored by nuclear magnetic resonance and Fourier-transform infrared to examine the basic chemistry; (2) short, model TPU's with different chemical structures blended with functional polymers including poly(ethylene glycol) and polybutadiene to explore the effect of interface in immiscible mixtures; (3) melt blending of a commercial TPU with polypropylene (PP), further involving more complicated morphology, using different types of functional PP's (note: amine functional PP's were prepared by melt amination) as compatibilizers followed by rheological, morphological, thermal, and mechanical characterizations. Besides the core thesis project on TPU blends, other related work that has been accomplished includes: (1) adhesion between TPU and PP; (2) rheological properties of TPU; (3) block copolymer formation

  13. Phosphorylcholine substituted polyolefins: New syntheses, solution assemblies, and polymer vesicles

    NASA Astrophysics Data System (ADS)

    Kratz, Katrina A.

    This thesis describes the synthesis and applications of a new series of amphiphilic homopolymers and copolymers consisting of hydrophobic polyolefin backbone and hydrophilic phosphorylcholine (PC) pendant groups. These polymers are synthesized by ring opening metathesis polymerization (ROMP) of a novel PC- cyclooctene monomer, and copolymerization of various functionalized cyclooctene comonomers. Incorporation of different comonomers into the PC-polyolefin backbone affords copolymers with different functionalities, including crosslinkers, fluorophores, and other reactive groups, that tune the range of applications of these polymers, and their hydrophobic/hydrophilic balance. The amphiphilic nature of PC-polyolefins was exploited in oil-water interfacial assembly, providing robust polymer capsules to encapsulate and deliver nanoparticles to damaged regions of a substrate in a project termed `repair-and-go.' In repair-and-go, a flexible microcapsule filled with a solution of nanoparticles probes an imperfection-riddled substrate as it rolls over the surface. The thin capsule wall allows the nanoparticles to escape the capsules and enter into the cracks, driven in part by favorable interactions between the nanoparticle ligands and the cracked surface (i.e., hydrophobic-hydrophobic interactions). The capsules then continue their transport along the surface, filling more cracks and depositing particles into them. The amphiphilic nature of PC-polyolefins was also exploited in aqueous assembly, forming novel polymer vesicles in water. PC-polyolefin vesicles ranged in size from 50 nm to 30 µm. The mechanical properties of PC-polyolefin vesicles were measured by micropipette aspiration techniques, and found to be more robust than conventional liposomes or polymersomes prepared from block copolymers. PC-polyolefin vesicles have potential use in drug delivery; it was found that the cancer drug doxorubicin could be encapsulated efficiently in PC-polyolefin vesicles. In

  14. Synthesis of polyolefin graft copolymers by borane approach

    SciTech Connect

    Jiang, G.J.; Rhubright, D.; Bernard, R.L.; Chung, T.C.

    1993-12-31

    This paper summarizes the new developments in the graft reaction of polyolefin by borane approach. It is becoming clear that the borane groups in polyolefins are valuable intermediates which not only can be quantitatively converted to a wide range of functional groups but also can be used as initiator or co-initiator for cationic or free radical polymerizations. Some interesting graft polymers, such as PP-g-PMMA, PP-g-PVA, PP-g-polycapolactone, EP-g-PMMA, and Butyl-g-PMMA, have been synthesized with controllable compositions and molecular microstructures. Most of them would be otherwise very difficult to prepare by the other existing methods. Several methods have been developed to incorporate borane groups to polyolefins, including both direct and post polymerizations. One unique feature of borane group is its excellent stability to transition metal catalysts, such as Ziegler-Natta, and good solubility in hydrocarbon solvents. These offer the possibility to prepare borane containing polyolefins with a broad range of copolymer composition and microstructure. In terms of application, graft copolymers are useful interfacial reagents in polyolefin blends and composites.

  15. Recycling-oriented characterization of polyolefin packaging waste.

    PubMed

    Hu, Bin; Serranti, Silvia; Fraunholcz, Norbert; Di Maio, Francesco; Bonifazi, Giuseppe

    2013-03-01

    Packaging waste is one of the main sources of secondary polyolefins. It is essential to characterize polyolefins derived from this waste stream in such way, that not only mechanical sorting methods can effectively separate, but also that on-line sensor systems can quantitatively assess their distribution. The characterization methodology is hierarchical, relating all properties of waste particles in any phase of the processing ultimately to the input End-Of-Life products. The present paper documents a pre-concentrate obtained by hand picking of mixed Romanian household waste. Investigations have been addressed to identify the composition of this polyolefin waste stream, to study the polyolefin density distribution, to distinguish the polymer manufacturing methods (i.e. injection molding and blow molding) by flake physical properties and finally to perform all the required characterization and identification by hyperspectral imaging. On the basis of these analyses, polyolefins from packaging wastes can be recycled by density separation and their rheological properties and wall thickness indicate the molding procedures. Hyperspectral imaging based procedures have been also applied to set up quality control actions for recycled products. PMID:23273624

  16. Nonmethane Hydrocarbons in Ambient Air of Hazy and Normal Days in Foshan, South China

    PubMed Central

    Guo, Songjun; Yang, Fumo; Tan, Jihua; Duan, Jingchun

    2012-01-01

    Abstract A first study of nonmethane hydrocarbons (NMHCs) on hazy and normal days was performed in Foshan for providing deep insight into the local deteriorating air quality. Ethane, propane, i-pentane, ethene, propene, ethyne, benzene, and toluene were eight most abundant compounds, accounting for 71%–85% of total NMHCs. Most hydrocarbons showed much higher levels on hazy days than normal days together with hydrocarbon/ethyne ratios and diurnal variations, indicating hazy days are more dominated by vehicular emission. Correlation coefficients (R2) of ethane, propane, ethane, propene, benzene, and total NMHCs with ethyne were 0.62–0.83, indicating these compounds are mainly related to vehicular emission. R2 analysis indicated that solvent usage is responsible for toluene and other aromatic hydrocarbons (e.g., ethylbezene). Benzene/toluene (B/T) ratio was 0.44±0.23 during whole sampling periods, again indicating vehicular emission is the dominant source. Lower B/T ratio (0.30±0.14) on hazy days than that (0.58±0.21) on normal days suggested that solvent usage emitted toluene. PMID:22493559

  17. [Light scattering extinction properties of atmospheric particle and pollution characteristics in hazy weather in Hangzhou].

    PubMed

    Xu, Chang; Ye, Hui; Shen, Jian-Dong; Sun, Hong-Liang; Hong, Sheng-Mao; Jiao, Li; Huang, Kan

    2014-12-01

    In order to evaluate the influence of particle scattering on visibility, light scattering coefficient, particle concentrations and meteorological factor were simultaneously monitored from July 2011 to June 2012 in Hangzhou. Daily scattering coefficients ranged from 108.4 to 1 098.1 Mm(-1), with an annual average concentration of 428.6 Mm(-1) ± 200.2 Mm(-1). Seasonal variation of scattering coefficients was significant, with the highest concentrations observed in autumn and winter and the lowest in summer. It was found there were two peaks for the average diurnal variations of the scattering coefficient, which could be observed at 08:00 and 21:00. The scattering efficiencies of PM2.5 and PM10 were 7.6 m2 x g(-1) and 4.4 m2 x g(-1), respectively. The particle scattering was about 90.2 percent of the total light extinction. The scattering coefficients were 684.4 Mm(-1) ± 218.1 Mm(-1) and 1 095.4 Mm(-1) ± 397.7 Mm(-1) in hazy and heavy hazy days, respectively, which were 2.6 and 4.2 times as high as in non-hazy weather, indicating that particle scattering is the main factor for visibility degradation and the occurrence of hazy weather in Hangzhou. PMID:25826909

  18. TRENDS OF SEASONAL HAZINESS AND SULFUR EMISSIONS OVER THE EASTERN U.S.

    EPA Science Inventory

    Reduction in visual range in the eastern U.S. is caused largely by sulfate particles. Therefore, it is expected that the spatial distribution and temporal trend of man-made haziness will, to some extent, correspond to the spatial-temporal pattern of sulfur emissions. The purpose ...

  19. Precision Polyolefin Nanoalloy Polypropylene/Poly(ε-caprolactone).

    PubMed

    Liu, Yuan; Wang, Ning; Dong, Jin-Yong

    2015-11-01

    This communication reports the first example of precision polyolefin nanoalloys where an exotic immiscible polymer is nanometrically dispersed with stability in a polyolefin matrix in a highly controlled mode. Following the preparation of polypropylene/multiwalled carbon nanotubes nanocomposites (PP/MWCNTs) by in situ Ziegler-Natta polymerization, the hydroxyl groups on the surfaces of individual MWCNTs are used to initiate ring-opening polymerization of ε-caprolactone, resulting in PP/poly(ε-caprolactone) (PCL) alloy with PCL grafted on MWCNTs. Upon phase formation, the PP/MWCNTs-g-PCL alloys exhibit a unique PCL dispersion morphology, which is stable and solely governed by PCL molecular weight. PMID:26345280

  20. Method for preparing polyolefin composites containing a phase change material

    DOEpatents

    Salyer, Ival O.

    1990-01-01

    A composite useful in thermal energy storage, said composite being formed of a polyolefin matrix having a phase change material such as a crystalline alkyl hydrocarbon incorporated therein. The composite is useful in forming pellets, sheets or fibers having thermal energy storage characteristics; methods for forming the composite are also disclosed.

  1. Characterization of Hexsyn, a polyolefin rubber.

    PubMed

    McMillin, C R

    1987-07-01

    Hexsyn is the Goodyear Tire and Rubber Company tradename for a polyolefin rubber synthesized from 1-hexene with 3-5% methylhexadiene as the source of residual double bonds for vulcanization. Under license from Goodyear, this same polymer has been manufactured by Lord Corporation for the hinge portion of finger joint prostheses using the tradename Bion. This rubber is currently licensed to the University of Akron and to the Cleveland Clinic Foundation for use in biomedical applications, and is being used primarily for biocompatible and highly fatigue resistant rubber components in ventricular assist and artificial heart systems. Results are presented from the physical, mechanical, and biological characterization of Hexsyn. Procedures are described for the synthesis, compounding, and post-molding extraction for Hexsyn. The physical testing of Hexsyn reported includes determinations of its density at 23 and 37 degrees C, initial hardness and hardness after aging in oxygen, blood, pseudoextracellular fluid and polyethylene glycol 600, typical molecular weights determined by gel permeation chromatography/low angle laser light scattering and intrinsic viscosity, thermal analyses by differential scanning calorimetry of Hexsyn gum, and vulcanized Hexsyn after exposure to blood and blood/fatigue conditions. Also reported are results of differential thermal analyses, thermomechanical analyses of virgin and annealed samples, and thermogravimetric analyses conducted in helium and in air. Dynamic mechanical analyses of Hexsyn include Clash-Berg and Rheovibron tests. Swelling was conducted to determine lot-to-lot and sheet-to-sheet variation for quality control and also a number of solvents were used so that the polymer-solvent interaction parameters could be determined. The permeability of Hexsyn to water, water vapor, and a variety of gases is reported. The permeability by contact angle measurements, refractive index, residual solvent analyses, migration of blood components

  2. Woven glass fabric reinforced laminates based on polyolefin wastes: Thermal, mechanical and dynamic-mechanical properties

    NASA Astrophysics Data System (ADS)

    Russo, Pietro; Acierno, Domenico; Simeoli, Giorgio; Lopresto, Valentina

    2014-05-01

    Potentialities of polyolefin wastes in place of virgin polypropylene to produce composite laminates have been investigated. Plaques reinforced with a woven glass fabric were prepared by film-stacking technique and systematically analyzed in terms of thermal, mechanical and dynamic-mechanical properties. In case of PP matrices, the use of a typical compatibilizer to improve the adhesion at the interface has been considered. Thermal properties emphasized the chemical nature of plastic wastes. About mechanical properties, static tests showed an increase of flexural parameters for compatibilized systems due to the coupling effect between grafted maleic anhydride and silane groups on the surface of the glass fabric. These effects, maximized for composites based on car bumper wastes, is perfectly reflected in terms of storage modulus and damping ability of products as determined by single-cantilever bending dynamic tests.

  3. Acid-functionalized polyolefin materials and their use in acid-promoted chemical reactions

    DOEpatents

    Oyola, Yatsandra; Tian, Chengcheng; Bauer, John Christopher; Dai, Sheng

    2016-06-07

    An acid-functionalized polyolefin material that can be used as an acid catalyst in a wide range of acid-promoted chemical reactions, wherein the acid-functionalized polyolefin material includes a polyolefin backbone on which acid groups are appended. Also described is a method for the preparation of the acid catalyst in which a precursor polyolefin is subjected to ionizing radiation (e.g., electron beam irradiation) of sufficient power and the irradiated precursor polyolefin reacted with at least one vinyl monomer having an acid group thereon. Further described is a method for conducting an acid-promoted chemical reaction, wherein an acid-reactive organic precursor is contacted in liquid form with a solid heterogeneous acid catalyst comprising a polyolefin backbone of at least 1 micron in one dimension and having carboxylic acid groups and either sulfonic acid or phosphoric acid groups appended thereto.

  4. Catalyst system for the polymerization of alkenes to polyolefins

    DOEpatents

    Miller, Stephen A.; Bercaw, John E.

    2004-02-17

    The invention provides metallocene catalyst systems for the controlled polymerization of alkenes to a wide variety of polyolefins and olefin coplymers. Catalyst systems are provided that specifically produce isotactic, syndiotactic and steroblock polyolefins. The type of polymer produced can be controlled by varying the catalyst system, specifically by varying the ligand substituents. Such catalyst systems are particularly useful for the polymerization of polypropylene to give elastomeric polypropylenes. The invention also provides novel elastomeric polypropylene polymers characterized by dyad (m) tacticities of about 55% to about 65%, pentad (mmmm) tacticities of about 25% to about 35%, molecular weights (M.sub.W) in the range of about 50,000 to about 2,000,000, and have mmrm+rrmr peak is less than about 5%.

  5. Catalyst system for the polymerization of alkenes to polyolefins

    DOEpatents

    Miller, Stephen A.; Bercaw, John E.

    2002-01-01

    The invention provides metallocene catalyst systems for the controlled polymerization of alkenes to a wide variety of polyolefins and olefin coplymers. Catalyst systems are provided that specifically produce isotactic, syndiotactic and steroblock polyolefins. The type of polymer produced can be controlled by varying the catalyst system, specifically by varying the ligand substituents. Such catalyst systems are particularly useful for the polymerization of polypropylene to give elastomeric polypropylenes. The invention also provides novel elastomeric polypropylene polymers characterized by dyad (m) tacticities of about 55% to about 65%, pentad (mmmm) tacticities of about 25% to about 35%, molecular weights (M.sub.w)in the range of about 50,000 to about 2,000,000, and have mmrm+rrmr peak is less than about 5%.

  6. Rheological properties of polyolefin composites highly filled with calcium carbonate

    NASA Astrophysics Data System (ADS)

    Nobile, Maria Rossella; Fierro, Annalisa; Jakubowska, Paulina; Sterzynski, Tomasz

    2016-05-01

    In this paper the rheological properties of highly filled polyolefin composites (HFPCs) have been investigated. Calcium carbonate (CaCO3), with stearic acid modified surface, was used as filler. Ternary compounds have been obtained by the inclusion of a CaCO3/polypropylene master batch into the high density polyethylene matrix. The highly filled polyolefin composites with CaCO3 content in the range between 40 and 64 wt% have been prepared in the molten state using a single-screw extruder, the temperature of the extrusion die was set at 230°C. The melt rheological properties of the HFPCs have been extensively investigated both in oscillatory and steady shear flow.

  7. Ultrasound imaging techniques in density separation of polyolefin waste.

    PubMed

    Sanaee, Seyed Ali; Bakker, M C M

    2012-12-01

    Ultrasound imaging techniques are investigated using a multi-element sensor array for purposes of monitoring and measurement ofpolyolefin waste particles inside the black ferrous liquid ofa magnetic density separator (MDS). A medical ultrasound imaging system with real-time capability was adapted first to assess the potential of imaging technology inside the MDS. An image processing routine was developed to determine the depth distribution of the detected particles as they are carried by the flow in the MDS channel. This real-time information is vital for optimizing the splitter position, which directly influences quality and recovery of the MDS polyolefin products. Despite successes in the laboratory, the medical technology proved unsatisfactory for continuous high-quality image forming in the industrial set-up as it requires regular operator intervention. Therefore, research has been initiated into alternative imaging methods, which are also being investigated in other fields such as non-destructive testing and geophysics. The influence of different ultrasound datasets and related image-forming techniques were investigated, for which dedicated algorithms were implemented in Matlab. The main advantages and disadvantages of the different techniques are addressed. It is concluded that the alternative imaging methods may be more robust and deliver higher image quality compared to the commercial medical imager. In particular, sizing of polyolefin particles may improve significantly if the method takes into account the correct ultrasound velocities of both the ferrous liquid and the immersed polyolefin particles. PMID:23437658

  8. Possible influence of atmospheric circulations on winter hazy pollution in Beijing-Tianjin-Hebei region, northern China

    NASA Astrophysics Data System (ADS)

    Zhang, Z.; Zhang, X.; Gong, D.; Kim, S.-J.; Mao, R.; Zhao, X.

    2015-08-01

    Using the daily records derived from the synoptic weather stations and the NCEP/NCAR and ERA-Interim reanalysis data, the variability of the winter hazy pollutions (indicated by the mean visibility and number of hazy days) in Beijing-Tianjin-Hebei (BTH) region during the period 1981 to 2015 and its relationship to the atmospheric circulations in middle-high latitude were analyzed in this study. The winter hazy pollution in BTH had distinct inter-annual and inter-decadal variabilities without a significant long-term trend. According to the spatial distribution of correlation coefficients, six atmospheric circulation indices (I1 to I6) were defined from the key areas in sea level pressure (SLP), zonal and meridional winds at 850 hPa (U850, V850), geopotential height field at 500 hPa (H500), zonal wind at 200 hPa (U200), and air temperature at 200 hPa (T200), respectively. All of the six indices have significant and stable correlations with the winter visibility and number of hazy days in BTH. Both the visibility and number of hazy days can be estimated well by using the six indices and fitting and the cross-validation with leave-N-out method, respectively. The high level of the prediction statistics and the reasonable mechanism suggested that the winter hazy pollutions in BTH can be forecasted or estimated credibly based on the optimized atmospheric circulation indices. However, we also noted that the statistic estimation models would be largely influenced by the artificial control of a pollutant discharge. Thus it is helpful for government decision-making departments to take actions in advance in dealing with probably severe hazy pollutions in BTH indicated by the atmospheric circulation conditions.

  9. Method of solution preparation of polyolefin class polymers for electrospinning processing included

    NASA Technical Reports Server (NTRS)

    Rabolt, John F. (Inventor); Lee, Keun-Hyung (Inventor); Givens, Steven R. (Inventor)

    2011-01-01

    A process to make a polyolefin fiber which has the following steps: mixing at least one polyolefin into a solution at room temperature or a slightly elevated temperature to form a polymer solution and electrospinning at room temperature said polymer solution to form a fiber.

  10. Stability of Diluted Adenosine Solutions in Polyolefin Infusion Bags

    PubMed Central

    Almagambetova, Elise; Hutchinson, David; Blais, Danielle M.; Zhao, Fang

    2013-01-01

    Background: Intravenous or intracoronary adenosine is used in the cardiac catherization lab to achieve maximal coronary blood flow and determine fractional flow reserve. Objective: To determine the stability of adenosine 10 and 50 µg/mL in either 0.9% sodium chloride injection or 5% dextrose injection in polyolefin infusion bags stored at 2 temperatures, refrigeration (2°C-8°C) or controlled room temperature (20°C-25°C). Methods: Adenosine 10 µg/mL and 50 µg/mL solutions were prepared in 50 mL polyolefin infusion bags containing 0.9% sodium chloride injection or 5% dextrose injection and stored at controlled room temperature or under refrigeration. Each combination of concentration, diluent, and storage was prepared in triplicate. Samples were assayed using stability-indicating, reversed-phase high-performance liquid chromatography immediately at time 0 and at 24 hours, 48 hours, 7 days, and 14 days. Stability was defined as retaining 90% to 110% of the initial adenosine concentration. The samples were also visually inspected against a light background for clarity, color, and the presence of particulate matter. Results: After 14 days, all samples retained 99% to 101% of the initial adenosine concentration. No considerable change in pH or visual appearance was noted. The stability data indicated no significant loss of drug due to chemical degradation or physical interactions during storage. Conclusion: Adenosine solutions of 10 and 50 µg/mL were stable for at least 14 days in 50 mL polyolefin infusion bags of 0.9% sodium chloride injection or 5% dextrose injection stored at controlled room temperature and refrigerated conditions. PMID:24421510

  11. Pyrolysis of polyolefins for increasing the yield of monomers' recovery

    SciTech Connect

    Donaj, Pawel J.; Kaminsky, W.; Buzeto, F.; Yang, W.

    2012-05-15

    Highlights: Black-Right-Pointing-Pointer Thermal and catalytic pyrolysis of mixed polyolefins in fluidized bed has been studied. Black-Right-Pointing-Pointer We tested applicability of a commercial Ziegler-Natta catalyst (Z-N: TiCl{sub 4}/MgCl{sub 2}). Black-Right-Pointing-Pointer The catalyst has a strong influence on product distribution, increasing gas fraction. Black-Right-Pointing-Pointer At 650 Degree-Sign C the monomer generation increased by 55% when the catalyst was used. Black-Right-Pointing-Pointer We showed the concept of treatment of mixed polyolefins without a need of separation. - Abstract: Pyrolysis of plastic waste is an alternative way of plastic recovery and could be a potential solution for the increasing stream of solid waste. The objective of this work was to increase the yield the gaseous olefins (monomers) as feedstock for polymerization process and to test the applicability of a commercial Ziegler-Natta (Z-N): TiCl{sub 4}/MgCl{sub 2} for cracking a mixture of polyolefins consisted of 46% wt. of low density polyethylene (LDPE), 30% wt. of high density polyethylene (HDPE) and 24% wt. of polypropylene (PP). Two sets of experiments have been carried out at 500 and 650 Degree-Sign C via catalytic pyrolysis (1% of Z-N catalyst) and at 650 and 730 Degree-Sign C via only-thermal pyrolysis. These experiments have been conducted in a lab-scale, fluidized quartz-bed reactor of a capacity of 1-3 kg/h at Hamburg University. The results revealed a strong influence of temperature and presence of catalyst on the product distribution. The ratios of gas/liquid/solid mass fractions via thermal pyrolysis were: 36.9/48.4/15.7% wt. and 42.4/44.7/13.9% wt. at 650 and 730 Degree-Sign C while via catalytic pyrolysis were: 6.5/89.0/4.5% wt. and 54.3/41.9/3.8% wt. at 500 and 650 Degree-Sign C, respectively. At 650 Degree-Sign C the monomer generation increased by 55% up to 23.6% wt. of total pyrolysis products distribution while the catalyst was added. Obtained

  12. Thermoplastic Adhesives based on polyolefin and olefinic copolymers

    NASA Astrophysics Data System (ADS)

    Paul, Rituparna

    2014-03-01

    H.B. Fuller has been a leading global industrial adhesive manufacturer for over 125 years. It is a company with a rich history of consistently delivering adhesive innovations for enhancing product performance in the market place. H.B. Fuller technologies/products find application in several markets including packaging, personal hygiene and nonwovens, durable assembly and electronics. In this presentation, H. B. Fuller's technology innovation journey will be shared with emphasis on groundbreaking technologies/products based on polyolefin and olefin copolymers.

  13. Titan solar occultation observations reveal transit spectra of a hazy world

    NASA Astrophysics Data System (ADS)

    Robinson, Tyler D.; Maltagliati, Luca; Marley, Mark S.; Fortney, Jonathan J.

    2014-06-01

    High altitude clouds and hazes are integral to understanding exoplanet observations, and are proposed to explain observed featureless transit spectra. However, it is difficult to make inferences from these data because of the need to disentangle effects of gas absorption from haze extinction. Here, we turn to the quintessential hazy world -- Titan -- to clarify how high altitude hazes influence transit spectra. We use solar occultation observations of Titan's atmosphere from the Visual and Infrared Mapping Spectrometer (VIMS) aboard NASA's Cassini spacecraft to generate transit spectra. Data span 0.88-5 microns at a resolution of 12-18 nm, with uncertainties typically smaller than 1%. Our approach exploits symmetry between occultations and transits, producing transit radius spectra that inherently include the effects of haze multiple scattering, refraction, and gas absorption. We use a simple model of haze extinction to explore how Titan's haze affects its transit spectru m. Our spectra show strong methane absorption features, and weaker features due to other gases. Most importantly, the data demonstrate that high altitude hazes can severely limit the atmospheric depths probed by transit spectra, bounding observations to pressures smaller than 0.1-10 mbar, depending on wavelength. Unlike the usual assumption made when modeling and interpreting transit observations of potentially hazy worlds, the slope set by haze in our spectra is not flat, and creates a variation in transit height whose magnitude is comparable to those from the strongest gaseous absorption features. These findings have important consequences for interpreting future exoplanet observations, including those from NASA's James Webb Space Telescope.

  14. The Pale Orange Dot: Spectral Effects of a Hazy Early Earth

    NASA Astrophysics Data System (ADS)

    Arney, G. N.; Meadows, V. S.; Domagal-Goldman, S. D.; Claire, M.; Schwieterman, E.

    2014-12-01

    Increasing evidence suggests Archean Earth had a photochemical hydrocarbon haze similar to Titan's (Zerkle et al. 2012), with important climate implications (Pavlov et al. 2001, Trainer et al. 2006, Haqq-Misra et al. 2008, Domagal-Goldman et al. 2008, Wolf and Toon 2012). Observations also suggest hazy exoplanets are common (Sing et al. 2011, Kreidberg et al 2014), so hazy planet spectra will be relevant to future exoplanet spectral characterization missions. Here, we consider the implications of hydrocarbon aerosols on the spectrum of Archean Earth, examining the effect of a haze layer on the detectability of spectral features from putative biosignatures and the Rayleigh scattering slope. We also examine haze's impact on the spectral energy distribution at the planetary surface, which may be important to the co-evolution of life with its environment. Because the atmospheric pressure and haze particle composition of the Archean Earth are poorly constrained, we test the impact of atmospheric pressure and particle density on haze formation. Our study uses a modified version of the 1-D photochemical code developed originally by Kasting et al. (1979) to generate a fractal haze in the model Archean atmosphere. The 1-D line-by-line fully multiple scattering Spectral Mapping Atmospheric Radiative Transfer Model (SMART) (Meadows and Crisp 1996) is then used to generate synthetic spectra of early Earth with haze. We find (Fig 1) that haze scattering significantly depletes the radiation at short wavelengths, strongly affecting the spectral region of the Rayleigh slope, a broadband change in spectral shape detectable at low spectral resolution. At the surface, the spectral energy distribution is shifted towards longer wavelengths, which may be important to photosynthetic life. Thus, the haze may have significant effects on biology, which in turn produces the methane that leads to haze formation, creating feedback loops between biology and the planet.

  15. Titan solar occultation observations reveal transit spectra of a hazy world.

    PubMed

    Robinson, Tyler D; Maltagliati, Luca; Marley, Mark S; Fortney, Jonathan J

    2014-06-24

    High-altitude clouds and hazes are integral to understanding exoplanet observations, and are proposed to explain observed featureless transit spectra. However, it is difficult to make inferences from these data because of the need to disentangle effects of gas absorption from haze extinction. Here, we turn to the quintessential hazy world, Titan, to clarify how high-altitude hazes influence transit spectra. We use solar occultation observations of Titan's atmosphere from the Visual and Infrared Mapping Spectrometer aboard National Aeronautics and Space Administration's (NASA) Cassini spacecraft to generate transit spectra. Data span 0.88-5 μm at a resolution of 12-18 nm, with uncertainties typically smaller than 1%. Our approach exploits symmetry between occultations and transits, producing transit radius spectra that inherently include the effects of haze multiple scattering, refraction, and gas absorption. We use a simple model of haze extinction to explore how Titan's haze affects its transit spectrum. Our spectra show strong methane-absorption features, and weaker features due to other gases. Most importantly, the data demonstrate that high-altitude hazes can severely limit the atmospheric depths probed by transit spectra, bounding observations to pressures smaller than 0.1-10 mbar, depending on wavelength. Unlike the usual assumption made when modeling and interpreting transit observations of potentially hazy worlds, the slope set by haze in our spectra is not flat, and creates a variation in transit height whose magnitude is comparable to those from the strongest gaseous-absorption features. These findings have important consequences for interpreting future exoplanet observations, including those from NASA's James Webb Space Telescope. PMID:24876272

  16. Titan solar occultation observations reveal transit spectra of a hazy world

    PubMed Central

    Robinson, Tyler D.; Maltagliati, Luca; Marley, Mark S.; Fortney, Jonathan J.

    2014-01-01

    High-altitude clouds and hazes are integral to understanding exoplanet observations, and are proposed to explain observed featureless transit spectra. However, it is difficult to make inferences from these data because of the need to disentangle effects of gas absorption from haze extinction. Here, we turn to the quintessential hazy world, Titan, to clarify how high-altitude hazes influence transit spectra. We use solar occultation observations of Titan’s atmosphere from the Visual and Infrared Mapping Spectrometer aboard National Aeronautics and Space Administration’s (NASA) Cassini spacecraft to generate transit spectra. Data span 0.88–5 μm at a resolution of 12–18 nm, with uncertainties typically smaller than 1%. Our approach exploits symmetry between occultations and transits, producing transit radius spectra that inherently include the effects of haze multiple scattering, refraction, and gas absorption. We use a simple model of haze extinction to explore how Titan’s haze affects its transit spectrum. Our spectra show strong methane-absorption features, and weaker features due to other gases. Most importantly, the data demonstrate that high-altitude hazes can severely limit the atmospheric depths probed by transit spectra, bounding observations to pressures smaller than 0.1–10 mbar, depending on wavelength. Unlike the usual assumption made when modeling and interpreting transit observations of potentially hazy worlds, the slope set by haze in our spectra is not flat, and creates a variation in transit height whose magnitude is comparable to those from the strongest gaseous-absorption features. These findings have important consequences for interpreting future exoplanet observations, including those from NASA’s James Webb Space Telescope. PMID:24876272

  17. End-Group-Functionalized Poly(α-olefinates) as Non-Polar Building Blocks: Self-Assembly of Sugar-Polyolefin Hybrid Conjugates.

    PubMed

    Thomas, Tessy S; Hwang, Wonseok; Sita, Lawrence R

    2016-04-01

    Living coordinative chain-transfer polymerization of α-olefins, followed by chemical functionalization of a Zn(polymeryl)2 intermediate, provides entry to end-group functionalized poly(α-olefinates) (x-PAOs) that can serve as a new class of non-polar building block with tailorable occupied volumes. Application of these x-PAOs for the synthesis and self-assembly of sugar-polyolefin hybrid conjugates demonstrate the ability to manipulate the morphology of the ultra-thin film nanostructure through variation in occupied volume of the x-PAO domain. PMID:26961338

  18. Method for the preparation of carbon fiber from polyolefin fiber precursor, and carbon fibers made thereby

    SciTech Connect

    Naskar, Amit Kumar; Hunt, Marcus Andrew; Saito, Tomonori

    2015-08-04

    Methods for the preparation of carbon fiber from polyolefin fiber precursor, wherein the polyolefin fiber precursor is partially sulfonated and then carbonized to produce carbon fiber. Methods for producing hollow carbon fibers, wherein the hollow core is circular- or complex-shaped, are also described. Methods for producing carbon fibers possessing a circular- or complex-shaped outer surface, which may be solid or hollow, are also described.

  19. Thermoplastic Elastomers via polyolefin/Layered Silicate Nanocomposites

    NASA Astrophysics Data System (ADS)

    Kalluru, Sri; Cochran, Eric

    2013-03-01

    Here we report the synthesis of fully exfoliated polyolefin nanocomposites via Surface-Initiated Ring Opening Metathesis Polymerization (SI-ROMP). Montmorillonite (MMT) clay platelets were rendered hydrophobic through ion exchange with alkyl-ammonium surfactants terminated with norbornene. We were then able to form block copolymer brushes of (substituted) norbornenes and cyclopentene via SI-ROMP. Subsequent hydrogenation yielded highly crystalline polyethylene and rubbery saturated polynorbornenes, thus giving a thermoplastic elastomer. Nanocomposites were prepared with different nanofiller percentages and were characterized for morphological (XRD, TEM), thermal (TGA, DSC), and mechanical (DMA, Rheology) properties. Complete exfoliation of nanocomposites was confirmed by XRD and TEM. A fraction of the polymer brushes were subsequently removed from their substrate by reverse ion exchange and characterized in parallel with their corresponding nanocomposite analogs. In this way we were able to directly assess the role of the filler particle in the thermal properties, melt rheology, morphology, and tensile properties.

  20. Pyrolysis of polyolefins for increasing the yield of monomers' recovery.

    PubMed

    Donaj, Pawel J; Kaminsky, W; Buzeto, F; Yang, W

    2012-05-01

    Pyrolysis of plastic waste is an alternative way of plastic recovery and could be a potential solution for the increasing stream of solid waste. The objective of this work was to increase the yield the gaseous olefins (monomers) as feedstock for polymerization process and to test the applicability of a commercial Ziegler-Natta (Z-N): TiCl(4)/MgCl(2) for cracking a mixture of polyolefins consisted of 46%wt. of low density polyethylene (LDPE), 30%wt. of high density polyethylene (HDPE) and 24%wt. of polypropylene (PP). Two sets of experiments have been carried out at 500 and 650°C via catalytic pyrolysis (1% of Z-N catalyst) and at 650 and 730°C via only-thermal pyrolysis. These experiments have been conducted in a lab-scale, fluidized quartz-bed reactor of a capacity of 1-3kg/h at Hamburg University. The results revealed a strong influence of temperature and presence of catalyst on the product distribution. The ratios of gas/liquid/solid mass fractions via thermal pyrolysis were: 36.9/48.4/15.7%wt. and 42.4/44.7/13.9%wt. at 650 and 730°C while via catalytic pyrolysis were: 6.5/89.0/4.5%wt. and 54.3/41.9/3.8%wt. at 500 and 650°C, respectively. At 650°C the monomer generation increased by 55% up to 23.6%wt. of total pyrolysis products distribution while the catalyst was added. Obtained yields of olefins were compared with the naphtha steam cracking process and other potentially attractive processes for feedstock generation. The concept of closed cycle material flow for polyolefins has been discussed, showing the potential benefits of feedstock recycling in a plastic waste management. PMID:22093704

  1. VOC characteristics, emissions and contributions to SOA formation during hazy episodes

    NASA Astrophysics Data System (ADS)

    Sun, Jie; Wu, Fangkun; Hu, Bo; Tang, Guiqian; Zhang, Junke; Wang, Yuesi

    2016-09-01

    Volatile organic compounds (VOC) are important precursors of secondary organic aerosols (SOA). The pollution processes in Beijing were investigated from 18th October to 6th November 2013 to study the characteristics, SOA formation potential and contributing factors of VOC during hazy episodes. The mean concentrations of VOC were 67.4 ± 33.3 μg m-3 on clear days and have 5-7-fold increase in polluted periods. VOC concentrations rapidly increased at a visibility range of 4-5 km with the rate of 25%/km in alkanes, alkenes and halocarbons and the rate of 45%/km in aromatics. Analysis of the mixing layer height (MLH); wind speed and ratios of benzene/toluene (B/T), ethylbenzene/m,p-xylene (E/X), and isopentane/n-pentane (i/n) under different visibility conditions revealed that the MLH and wind speed were the 2 major factors affecting the variability of VOC during clear days and that local emissions and photochemical reactions were main causes of VOC variation on polluted days. Combined with the fractional aerosol coefficient (FAC) method, the SOA formation potentials of alkanes, alkenes and aromatics were 0.3 ± 0.2 μg m-3, 1.1 ± 1.0 μg m-3 and 6.5 ± 6.4 μg m-3, respectively. As the visibility deteriorated, the SOA formation potential increased from 2.1 μg m-3 to 13.2 μg m-3, and the fraction of SOA-forming aromatics rapidly increased from 56.3% to 90.1%. Initial sources were resolved by a positive matrix factorization (PMF) model. Vehicle-related emissions were an important source of VOC at all visibility ranges, accounting for 23%-32%. As visibility declined, emissions from solvents and the chemical industry increased from 13.2% and 6.3% to 34.2% and 23.0%, respectively. Solvents had the greatest SOA formation ability, accounting for 52.5% on average on hazy days, followed by vehicle-related emissions (20.7%).

  2. Control of PM2.5 in Guangzhou during the 16th Asian Games period: implication for hazy weather prevention.

    PubMed

    Tao, Jun; Zhang, Leiming; Zhang, Zhisheng; Huang, Ruijin; Wu, Yunfei; Zhang, Renjian; Cao, Junji; Zhang, Yuanhang

    2015-03-01

    To evaluate the effectiveness of the integrated control measures for reducing PM2.5 (aerosol particles with an aerodynamic diameter of less than 2.5 μm) and hazy weather, day- and night-time PM2.5 samples were collected at an urban site in Guangzhou during the 16th Asian Games period in November 2010. PM2.5 samples were subject to chemical analysis for major water-soluble ions, organic carbon (OC), element carbon (EC), and biomass burning tracers-anhydrosugar levoglucosan (LG). In addition, aerosol scattering coefficient (bsp) at dry condition and aerosol absorption coefficient (bap) and visibility at ambient condition were measured. The seven major control measures were effective for reducing PM2.5 mass concentration and improving visibility during the Asian Games period. All monitored air pollutants except PM2.5 satisfied the National Ambient Air Quality Standards (NAAQS). However, daily PM2.5 concentrations still exceeded the NAAQS on 47% of the days and hazy weather also occurred on 80% of the days during this period. One factor causing the high frequency of hazy weather occurrence was the increased relative humidity during the Asian Games period. To avoid hazy weather occurrence, new PM2.5 standard was recommended based on visibility calculations using three available aerosol hygroscopic curves previously obtained for this city. The recommended PM2.5 standard was 63 μgm(-3) under dry condition and lower than 42 μg m(-3) under humid condition (RH ≥ 70%). These recommended value s were much stricter than the NAAQS value of 75 μg m(-3). To reach the new standard, more rigorous control measures for coal industries should be established in the Pearl River Delta (PRD) region. PMID:25437953

  3. Investigation of relationships between linears, total and hazy areas, and petroleum production in the Williston Basin: An ERTS approach

    NASA Technical Reports Server (NTRS)

    Erickson, J. M.; Street, J. S. (Principal Investigator); Munsell, C. J.; Obrien, D. E.

    1975-01-01

    The author has identified the following significant results. ERTS-1 imagery in a variety of formats was used to locate linear, tonal, and hazy features and to relate them to areas of hydrocarbon production in the Williston Basin of North Dakota, eastern Montana, and northern South Dakota. Derivative maps of rectilinear, curvilinear, tonal, and hazy features were made using standard laboratory techniques. Mapping of rectilinears on both bands 5 and 7 over the entire region indicated the presence of a northeast-southwest and a northwest-southeast regional trend which is indicative of the bedrock fracture pattern in the basin. Curved lines generally bound areas of unique tone, maps of tonal patterns repeat many of the boundaries seen on curvilinear maps. Tones were best analyzed on spring and fall imagery in the Williston Basin. It is postulated that hazy areas are caused by atmospheric phenomena. The ability to use ERTS imagery as an exploration tool was examined where petroleum and gas are presently produced (Bottineau Field, Nesson and Antelope anticlines, Redwing Creek, and Cedar Creek anticline). It is determined that some tonal and linear features coincide with location of present production in Redwing and Cedar Creeks. In the remaining cases, targets could not be sufficiently well defined to justify this method.

  4. Thermal properties of polyolefin composites with copper silicate

    NASA Astrophysics Data System (ADS)

    Klozinski, Arkadiusz; Jakubowska, Paulina; Ambrozewicz, Damian; Jesionowski, Teofil

    2015-05-01

    The aim of this work was to specify thermal properties of polyolefin composites with copper silicate. Low density polyethylene (LDPE) and polypropylene (PP) composites with 2, 4 and 8 wt % of the filler (CuO.SiO2) were analyzed. Characteristic temperatures of the polymer compositions, i.e. the melting (Tm) and crystallization temperatures (Tc), obtained by means of Differential Scanning Calorimetry (DSC), were determined. The impact of the applied additives on composites thermal stability was established using thermogravimetry measurements (TGA). Afterwards, the flammability test was performed. The measurement was complemented with the establishment of the maximum combustion temperature using infrared recording techniques and image analysis (infrared camera). One of the most important parameter of thermoplastics is the softening point which was also determined. The measurement was carried out using a Vicat apparatus. Thermal characteristic was also supplemented with an assessment of the thermal diffusivity (the parameter determining the cooling time in an injection mold). The tests were conducted using the modified Angstrom method and an infrared camera.

  5. Predictive modeling of metal-catalyzed polyolefin processes

    NASA Astrophysics Data System (ADS)

    Khare, Neeraj Prasad

    2003-10-01

    This dissertation describes the essential modeling components and techniques for building comprehensive polymer process models for metal-catalyzed polyolefin processes. The significance of this work is that it presents a comprehensive approach to polymer process modeling applied to large-scale commercial processes. Most researchers focus only on polymerization mechanisms and reaction kinetics, and neglect physical properties and phase equilibrium. Both physical properties and phase equilibrium play key roles in the accuracy and robustness of a model. This work presents the fundamental principles and practical guidelines used to develop and validate both steady-state and dynamic simulation models for two large-scale commercial processes involving the Ziegler-Natta polymerization to produce high-density polyethylene (HDPE) and polypropylene (PP). It also provides a model for the solution polymerization of ethylene using a metallocene catalyst. Existing modeling efforts do not include physical properties or phase equilibrium in their calculations. These omissions undermine the accuracy and predictive power of the models. The forward chapters of the dissertation discuss the fundamental concepts we consider in polymer process modeling. These include physical and thermodynamic properties, phase equilibrium, and polymerization kinetics. The later chapters provide the modeling applications described above.

  6. Size-fractionated water-soluble ions, situ pH and water content in aerosol on hazy days and the influences on visibility impairment in Jinan, China

    NASA Astrophysics Data System (ADS)

    Cheng, Shu-hui; Yang, Ling-xiao; Zhou, Xue-hua; Xue, Li-kun; Gao, Xiao-mei; Zhou, Yang; Wang, Wen-xing

    2011-09-01

    To study the size-fractionated characteristics of aerosol chemical compounds including major water-soluble inorganic and organic ions, situ pH and water content as well as their influences on visibility, field sample collections using a Micro Orifice Uniform Deposit Impactor (MOUDI) combined with simulations by Aerosol Inorganic Model (AIM) were conducted on hazy and clear days in Jinan, China from April, 2006 to January, 2007. Average concentrations of TSP, PM 10 and PM 1.8 on hazy days were found to be 1.49-5.13, 1.54-5.48 and 1.30-5.48 times those on clear days during the sampling periods, indicating that particulate pollution was very serious on hazy days. Size distributions of mass, SO 42-, NO 3-, formate and acetate were all bimodal with fine mode predominant on hazy days, demonstrating that fine particles and secondary pollutants were more easily formed on hazy days. The average total aerosol concentration of H + ([H +] total), of which free H + concentration ([H +] ins) inside aerosol accounted for 30%, was 2.36-4.21 times that in other cities in China and US. The [H +] ins on hazy days was 2.43-13.11 times that on clear days and the estimated situ pH was mainly influenced by RH and mole ratios of [NH 4+]/[SO 42-]. Size distributions of situ pH were unimodal peaked at 0.56 μm on clear days in spring and autumn as well as on hazy days in autumn, while a trend of increasing was shown on hazy days in spring and summer. The normalized water content (NWC) was higher on hazy days in autumn and winter because of the easier uptake of water by aerosol. It was found that when NWC < 2, if [NH 4+]/[SO 42-] < 2.0, aerosol chemical components were more sensitive to water content, while if [NH 4+]/[SO 42-] > 2.0, relative humidity (RH) was more important. Size distributions of water content showed a trend of sharp increasing on hazy days in spring and autumn. Correlation and regression analysis indicated that visibility was significantly influenced by the concentrations

  7. Aerosol physical properties and Radiative forcing at the outflow region from the Indo-Gangetic plains during typical clear and hazy periods of wintertime

    NASA Astrophysics Data System (ADS)

    Niranjan, K.; Sreekanth, V.; Madhavan, B. L.; Krishna Moorthy, K.

    2007-10-01

    Results of a campaign mode measurements of column integrated aerosol optical depths, near surface mass concentrations and LIDAR profiles during winter 2004 at Kharagpur located at the vent of the out flow region from the Indo-Gangetic plains are presented with a view to characterize the atmospheric aerosol radiative forcing during hazy and clear sky conditions. The multispectral optical depths, surface mass concentrations and black carbon are high, while a decrease in Angstrom exponent value was observed during the hazy sky days. During hazy conditions, the LIDAR profiles show a decrease in the mixed layer height leading to confinement and subsidence of aerosols. Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART) model along with Optical Properties of Aerosols and Clouds (OPAC) are used to perform composite aerosol forcing estimation, incorporating LIDAR derived mixed layer heights. A considerable decrease in estimated single scattering albedo has been observed during hazy sky days. The atmospheric absorption during hazy sky days increased by 75% compared to clear days. Negative forcing was observed both at the top of the atmosphere and at the surface. The forcing estimates of the present study are compared with the similar studies over other locations in the Indo-Gangetic plains during the campaign period.

  8. The Pale Orange Dot: Spectral Effects of a Hazy Early Earth

    NASA Astrophysics Data System (ADS)

    Arney, G.; Domagal-Goldman, S.; Meadows, V.

    2014-03-01

    Several studies have suggested that the Archean Earth atmosphere had a photochemically generated hydrocarbon haze similar to that of Titan, with important climactic implications for our early planet (Pavlov et al. 2001, Trainer al al. 2006, Haqq-Misra et al. 2008, Domagal-Goldman et al. 2008, Wolf and Toon 2012, Zerkle et al. 2012). Haze forms when the ratio of CH4 to CO2 in the atmosphere reaches ~0.1 (Haqq-Misra et al. 2008), and the resultant hydrocarbon haze can contain fractal particles. Compared to spherical particles, fractal particles produce less antigreenhouse cooling and can act as a UV shield (Wolf and Toon 2012), potentially enhancing the habitability of our young planet. If hazy exoplanets are common, the effects of hazes on planetary spectra will be relevant to future exoplanet spectral characterization missions. Previous studies of the detectability of biosignatures on early Earth (e.g. Kaltenegger et al. 2007) have not incorporated the effect of hazes. We consider the implications of spherical and fractal organic aerosol hazes on the spectrum of Archean Earth, examining in particular the impact of a haze layer in discerning spectral features from H2O, CH4, and other gases that have been suggested as putative biosignatures on anoxic planets such as C2H6 (Domagal-Goldman et al. 2011). We use a modified version of the 1-D photochemical code developed originally by Kasting et al. (1979) to generate a self-consistent haze in the model Archean atmosphere. The 1-D line-by-line fully multiple scattering Spectral Mapping Atmospheric Radiative Transfer Model (SMART) (Meadows and Crisp 1996) is then used to generate synthetic spectra of early Earth with haze. In the thermal IR, haze decreases the effective emitting temperature, so the planet appears colder than its surface temperature would dictate. Haze scattering significantly depletes the radiation at short wavelengths, but at longer visible wavelengths the haze increases the reflectivity making the planet

  9. Preparation and characterization of polyolefin/nanosilica composites

    NASA Astrophysics Data System (ADS)

    Bailly, Mathieu

    Polypropylene (PP) and ethylene-co-octene copolymer (EOC) blends were prepared at various component ratios and reinforced with silica nanoparticles (SiO2). Strategies to improve filler dispersion involved the grafting of a silane coupling agent on the PP matrix, the addition of a maleated PP (PP-g-MA) as a compatibilizer and the use of hydrophobic silica nanoparticles. These approaches resulted in a fine dispersion of the nanoparticles within the PP phase and induced a reduction of the size of the EOC domains, due to a barrier effect. Tensile and flexural properties were significantly increased, whereas ductility and impact properties were not affected. These enhancements are attributed to the favourable microstructure of the blends, featuring a segregated microstructure, and to the improved interfacial adhesion between the functionalized polymer matrix and the surface of the nanoparticles. The microstructure and rheology of model melt compounded EOC-based nanocomposites were investigated. Functionalization of the polyolefin matrix was accomplished through silane grafting, or addition of a maleated EOC (EOC-g-MA) compatibilizer. Various grades of unmodified SiO2 having different specific surface areas (SSA), as well as a surface-modified grade were added to the EOC matrix at various loadings. The formation of covalent and hydrogen bonds between the silanol groups and the functionalized polymer generated strong polymer/filler (P/F) interactions, resulting in improved filler dispersion. Bound polymer characterization revealed that in the compatibilized materials, the amount of polymer physically attached to the nanoparticles was higher than in the non-compatibilized samples. In the absence of a compatibilizer, larger SiO2 aggregates formed upon increasing SSA because of increased probability of hydrogen bonding between the particles. The increased propensity for aggregation was revealed by time sweeps as well as by the increased strain sensitivity in stress sweeps

  10. A study of the physical, chemical, and optical properties of ambient aerosol particles in Southeast Asia during hazy and nonhazy days

    NASA Astrophysics Data System (ADS)

    See, S. W.; Balasubramanian, R.; Wang, W.

    2006-05-01

    Many Southeast Asian countries have been constantly plagued by recurring smoke haze episodes as a result of traditional slash-and-burn practices in agricultural areas to clear crop lands or uncontrolled forest fires. However, our current knowledge on the physiochemical and optical properties of ambient aerosols associated with regional haze phenomenon is still fairly limited. Therefore a comprehensive field study was carried out in Singapore from March 2001 to March 2002 under varying weather conditions to gain a better understanding of the characteristics. The physical (size distribution of mass and number concentrations), chemical (mass concentrations of chemical components: 14 ions, 24 metals, elemental carbon (EC) and organic carbon (OC)), and optical (light absorption (bap) and scattering (bsp) by particles) characteristics of ambient aerosol particles were investigated. The results are reported separately for clear and hazy days by categorizing the days as clear or hazy on the basis of visibility data. It was observed that the average concentrations of PM2.5 and most chemical components increased approximately by a factor of 2 on hazy days. Backward air trajectories together with the hot spot distributions in the region indicated that the degradation in Singapore's air quality on hazy days was attributable to large-scale forest fires in Sumatra. This visibility degradation was quantitatively measured on the basis of the light absorption and scattering by particles. As expected, scattering rather than absorption controlled atmospheric visibility, and PM2.5 particles present on hazy days were more efficient at scattering light than those found on clear days.

  11. Determination of antioxidants in polyolefins using total dissolution methodology followed by RPLC.

    PubMed

    Green, Shayne; Bai, Snow; Cheatham, Mike; Cong, Rongjuan; Yau, Wallace

    2010-11-01

    Antioxidants are added to polyolefins to improve the stability of the resin from oxidation and degradation during processing of the finished article and to increase product lifetime. Without antioxidants, polyolefins would quickly degrade during and after the extrusion or thermoforming process, which would cause inferior appearance and physical properties. The proper level must be added to protect the polymer and to minimize cost. Antioxidants are usually extracted from the resin and the extract is analyzed by RPLC, GC, or Fourier transform infrared spectroscopy. Unfortunately, many of these procedures require significant manual labor, time, and solvent, rendering them impractical for high-throughput work processes. In addition, they may not provide complete extraction of the additives depending upon the type of resin. A validated analytical method was needed for the determination of three common antioxidants, Irganox(®) 1010, Irganox(®) 1076, and Irgafos(®) 168 in polyolefin resins. This paper shows the determination of these antioxidants using dissolution followed by precipitation with o-xylene and methanol. Direct analysis of the solution is achieved in 8 min using RPLC. PMID:20886522

  12. High strain deformation behavior of semicrystalline polyolefins and blends

    NASA Astrophysics Data System (ADS)

    Chang, Andy Cheng

    The stress-strain response of fringed micellar ethylene-octene (EO) and ethylene-styrene (ES) copolymers were compared from the glass transition (Tg) to the crystal melting region. Above the onset of Tg, the copolymers were elastomeric. In the glass transition range, an initial elastomeric response was followed by high strain yielding and strain hardening characteristic of plastic deformation. This behavior was defined as elastomeric-plastic. The concept of a network of flexible chains, interconnected by multifunctional fringed micellar crystals providing for elastomeric behavior, was extended to elastomeric-plastic behavior by considering a fraction of rigid, glassy chains. Based on this structural interpretation, the slip-link theory was applied to the initial elastomeric response in elastomeric-plastic deformation. Lateral attachment and detachment of crystallizable sequences at the crystal edges provided the sliding topological constraint (slip-links), and entanglements that tightened into rigid knots upon stretching functioned as permanent junctions (cross-links). Increasing the fraction of glassy chains hindered the mobility of slip-links and reduced mobility of the amorphous phase resulting in higher strain-hardening. Shifting with respect to thermal transitions accounted for differences between ES and EO copolymers. Blown film with up to 30 wt% of a high melt strength polypropylene (hmsPP) blended with either a conventional Ziegler-Natta linear low density polyethylene (znPE) or a blend of a Ziegler-Natta and a metallocene linear low density polyethylene (zn/mPE) was examined using atomic force microscopy (AFM) and wide angle x-ray scattering (WAXS). Confined to thin elongated domains in blends with polyethylene, hmsPP crystallized as planar shish-kebabs on which polyethylene epitaxially crystallized in the characteristic herringbone texture. Analysis of the blown film surfaces by AFM under increasing tapping hardness revealed surface segregation of

  13. Phosphorescent oxygen sensors based on nanostructured polyolefin substrates.

    PubMed

    Gillanders, Ross N; Arzhakova, Olga V; Hempel, Andreas; Dolgova, Alla; Kerry, Joe P; Yarysheva, Larisa M; Bakeev, Nikolai F; Volynskii, Alexander L; Papkovsky, Dmitri B

    2010-01-15

    New phosphorescent oxygen-sensitive materials based on nanostructured high density polyethylene and polypropylene films are described. The polymer substrates undergo treatment by a solvent crazing process to create a well-developed network of controlled, nanometer-size pores. Indicator dye molecules are then embedded by physical entrapment in such nanostructures which subsequently can be healed. Such sensors demonstrate improved working characteristics and allow simple, cost-efficient production and disposable use. They are well suited for large-scale applications such as nondestructive control of residual oxygen and "smart" packaging. PMID:20038091

  14. Dismantlable Thermosetting Adhesives Composed of a Cross-Linkable Poly(olefin sulfone) with a Photobase Generator.

    PubMed

    Sasaki, Takeo; Hashimoto, Shouta; Nogami, Nana; Sugiyama, Yuichi; Mori, Madoka; Naka, Yumiko; Le, Khoa V

    2016-03-01

    A novel photodetachable adhesive was prepared using a photodepolymerizable cross-linked poly(olefin sulfone). A mixture of a cross-linkable poly(olefin sulfone), a cross-linking reagent, and a photobase generator functioned as a thermosetting adhesive and exhibited high adhesive strength on quartz plates comparable to that obtained for commercially available epoxy adhesives. The cured resin was stable in the absence of UV light irradiation but completely lost its adhesive strength upon exposure of glued quartz plates to UV light in conjunction with heating to 100 °C. PMID:26872271

  15. Fabrication of nanofillers into a granular "nanosupport" for Ziegler-Natta catalysts: towards scalable in situ preparation of polyolefin nanocomposites.

    PubMed

    Qin, Yawei; Wang, Ning; Zhou, Yong; Huang, Yingjuan; Niu, Hui; Dong, Jin-Yong

    2011-07-15

    This communication reports a strategy for scale-up of an in situ polymerization technique for polyolefin-based nanocomposites preparation, taking layered silicate (clay) and multi-walled carbon nanotubes (MWCNTs) as examples of nanofillers. The strategy is realized by transforming the nanofillers into granular "nanosupports" for Ziegler-Natta catalysts. With a catalyst to polymer replication effect on particle morphology, the in situ prepared nanocomposites are of controlled granular particle morphology. With the polymer particle morphology controlled, the in situ polymerization technique becomes suitable for industrial olefin polymerization processes for mass production of polyolefin nanocomposites. PMID:21618321

  16. The measurement of low-frequency linear viscoelastic properties of polyolefins using creeping squeeze flow

    NASA Astrophysics Data System (ADS)

    Cua, Edwin Matthew Chua

    The characterization of the low-frequency linear viscoelastic properties of polymers is a classical problem in rheometry, especially for broad molecular weight (MW), fractional melt-flow index (MFI) polyolefins with small time-temperature shift factors. By interconversion of high-temperature, low-shear steady-viscosity data in the terminal flow regime into low-frequency data using the Cox-Merz rule, the experimental window is expanded towards lower frequencies. A squeeze-flow apparatus using Newton interferometry as a drift-free transducer to measure the gap between a spherical lens and a flat glass plate with high spatial resolution was constructed. Trials with a Newtonian silicone oil and a viscoelastic polydimethylsiloxane (PDMS) gum were undertaken to examine the various experimental factors that might contribute to errors in the calculation of the viscosity. After taking into account those factors during the runs with PDMS gum, the squeeze-flow-derived viscosities at the terminal flow regime (at shear rates accessible to a commercial rheometer) were in good agreement with low frequency dynamic data. To achieve much lower shear rates for the runs with polyolefins, an increase in the working gap range was made by switching from Newton interferometry to Fizeau interferometry. A hermetically sealed high vacuum chamber was built to allow high-temperature runs with polyolefins with minimal degradation. Interconversion of the measured viscosities of a broad MW, 1.04 MFI high-density polyethylene (HDPE) with the squeeze flow apparatus resulted in complex viscosity data at ˜10-5 rad/s, expanding the experimental window by 2 decades. The squeeze-flow derived complex viscosity data was used to decide which of the two popular viscosity models was more accurate in predicting the zero-shear rate viscosity based on its fit to dynamic data limited to higher frequencies.

  17. Stability of Glutamate-Aspartate Cardioplegia Additive Solution in Polyolefin IV Bags

    PubMed Central

    Rush, Steven D.; Kim, Stephanie E.; Hughes, Susan E.; Gilbert, Justine M.; Ciancaglini, Peter P.

    2015-01-01

    Objective: Glutamate-aspartate cardioplegia additive solution (GACAS) is used to enhance myocardial preservation and left ventricular function during some cardiac surgeries. This study was designed to evaluate the stability of compounded GACAS stored in sterile polyolefin intravenous (IV) bags. The goal is to extend the default USP beyond-use date (BUD) and reduce unnecessary inventory waste. Methods: GACAS was compounded and packaged in sterile polyolefin 250 mL IV bags. The concentration was 232 mM for each amino acid. The samples were stored under refrigeration (2°C-8°C) and analyzed at 0, 1, and 2 months. At each time point, the samples were evaluated by pH measurement and visual inspection for color, clarity, and particulates. The samples were also analyzed by high-performance liquid chromatography (HPLC) for potency and degradation products. Due to the lack of ultraviolet (UV) chromophores of glutamate and aspartate, the samples were derivatized by ortho-phthalaldehyde prior to HPLC analysis. Results: The time zero samples of GACAS passed the physical, chemical, and microbiological tests. Over 2 months of storage, there was no significant change in pH or visual appearance for any of the stability samples. The HPLC results also indicated that the samples retained 101% to 103% of the label claim strengths for both amino acids. Conclusion: The physical and chemical stability of extemporaneously prepared GACAS has been confirmed for up to 2 months in polyolefin IV bags stored under refrigeration. With proper sterile compounding practice and microbiology testing, the BUD of this product can be extended to 2 months. PMID:26405344

  18. Evaluation of oxidative behavior of polyolefin geosynthetics utilizing accelerated aging tests based on temperature and pressure

    NASA Astrophysics Data System (ADS)

    Li, Mengjia

    Polyolefin geosynthetics are susceptible to oxidation, which eventually leads to the reduction in their engineering properties. In the application of polyolefin geosynthetics, a major issue is an estimate of the materials durability (i.e. service lifetime) under various aging conditions. Antioxidant packages are added to the polyolefin products to extend the induction time, during which antioxidants are gradually depleted and polymer oxidation reactions are prevented. In this PhD study, an improved laboratory accelerating aging method under elevated and high pressure environments was applied to evaluate the combined effect of temperature and pressure on the depletion of the antioxidants and the oxidation of polymers. Four types of commercial polyolefn geosynthetic materials selected for aging tests included HDPE geogrid, polypropylene woven and nonwoven geotextiles. A total of 33 different temperature/pressure aging conditions were used, with the incubation duration up to 24 months. The applied oven temperature ranged from 35°C to 105°C and the partial oxygen pressure ranged from 0.005 MPa to 6.3 MPa. Using the Oxidative Induction Time (OIT) test, the antioxidant depletion, which is correlated to the decrease of the OIT value, was found to follow apparent first-order decay. The OIT data also showed that, the antioxidant depletion rate increased with temperature according to the Arrhenius equation, while under constant temperatures, the rate increased exponentially with the partial pressure of oxygen. A modified Arrhenius model was developed to fit the antioxidant depletion rate as a function of temperature and pressure and to predict the antioxidant lifetime under various field conditions. This study has developed new temperature/pressure incubation aging test method with lifetime prediction models. Using this new technique, the antioxidant lifetime prediction results are close to regular temperature aging data while the aging duration can be reduced considerably

  19. Thermotropic rod-like mesogens as stabilizers for polyolefins and polyvinyl chloride

    NASA Astrophysics Data System (ADS)

    Burmistrov, V. A.; Kuvshinova, S. A.; Koifman, O. I.

    2016-02-01

    The main approaches to stabilization of polymers and requirements to anti-ageing agents are discussed. Considerable attention is paid to the progress in the studies of the stabilizing activity of various substances in polyolefin- and polyvinyl chloride-based compositions. Particular demand for environmentally benign organic heat stabilizers and antioxidants is noted. The so-called mesogenic structures serving as effective light and heat stabilizers for polymer composites are presented. The effects of mesogens on the supramolecular structure of polyethylene, deformation and relaxation properties and thermal parameters as well as melt flow index, tribological properties and other properties of polymer materials are discussed. The bibliography includes 112 references.

  20. Processability improvement of polyolefins through radiation-induced branching

    NASA Astrophysics Data System (ADS)

    Cheng, Song; Phillips, Ed; Parks, Lewis

    2010-03-01

    Radiation-induced long-chain branching for the purpose of improving melt strength and hence the processability of polypropylene (PP) and polyethylene (PE) is reviewed. Long-chain branching without significant gel content can be created by low dose irradiation of PP or PE under different atmospheres, with or without multifunctional branching promoters. The creation of long-chain branching generally leads to improvement of melt strength, which in turn may be translated into processability improvement for specific applications in which melt strength plays an important role. In this paper, the changes of the melt flow rate and the melt strength of the irradiated polymer and the relationship between long-chain branching and melt strength are reviewed. The effects of the atmosphere and the branching promoter on long-chain branching vs. degradation are discussed. The benefits of improved melt strength on the processability, e.g., sag resistance and strain hardening, are illustrated. The implications on practical polymer processing applications such as foams and films are also discussed.

  1. Structure-Property Relationships in Polyolefin Block Copolymers

    NASA Astrophysics Data System (ADS)

    Mansour, Ameara Salah

    Poly(cyclohexylethylene) (PCHE for a homopolymer or C in a block copolymer) is created by hydrogenating polystyrene, and this polymer exhibits interesting properties, such as a high glass transition temperature (147 °C), high flexural modulus (2.8 GPa), low stress optical coefficient (-0.2 * 10-9 Pa-1), and low cost. However, the inherently brittle nature of PCHE prevents it from being used in applications that simultaneously require high modulus, ductility, thermal stability, and optical clarity. Previous research has shown that incorporating PCHE into a block copolymer with rubbery poly(ethylene-alt-propylene) (P) or poly(ethylethylene) (EE) or semicrystalline polyethylene (E) results in a tough material. In some cases, applications also require specific mechanical or optical properties. In order to tune these properties, this research examined tuning crystallinity using two methods: (1) by controlling the microstructure of the soft block by synthesizing a random copolymer of E and EE, and (2) by blending high C content pentablock copolymers with semicrystalline and rubbery minority components. In the first study, diblock copolymers of C(EcoEE) also were used to understand how the microstructure of the random copolymer affects the thermodynamics of the system. In the second study, CECEC and CPCPC, designed to form the same morphology (hexagonally packed cylinders with glassy C matrices), and have similar order-to-disorder transition temperatures and domain spacings, were blended together. Isothermal crystallization experiments were used to determine how the confining E and P in one domain affects the crystallization process. The effect of architecture, the state of the minority component, and the percent crystallinity on the mechanical properties of high glass content materials was also examined. These results were compared to the mechanical properties of homopolymer PCHE, polystyrene, and polycarbonate. The processing conditions needed to create smooth films of

  2. Characterization of functionalized polyolefins by high-temperature two-dimensional liquid chromatography.

    PubMed

    Ginzburg, Anton; Macko, Tibor; Malz, Frank; Schroers, Michael; Troetsch-Schaller, Irene; Strittmatter, Jan; Brüll, Robert

    2013-04-12

    High-temperature two-dimensional liquid chromatography (HT 2D-LC) was developed for the separation and characterization of functional polyolefins. Therefore, the key experimental parameters, namely the injection volume, the mobile phase composition, the flow rate in SEC and the time and phase of sampling into the second dimension, were systematically varied and their influence on the resolution of separation were studied. The HPLC separation of ethylene-vinylacetate waxes was realized using silica gel as stationary phase and a solvent gradient decalin→cyclohexanone, while SEC separations were realized in the chromatographic system polystyrene divinyl benzene column/1,2,4-trichlorobenzene. By choosing suitable experimental parameters, the run time needed for one complete 2D-LC analysis of a polymer sample was shortened from about 200 min to 100 min. However, the developed method failed to adsorb polypropylene and ethylene/1-butene copolymers grafted with 13 or 3 mol.% of methyl methacrylate respectively. Using porous graphite as a stationary phase and a solvent gradient 1-decanol→1,2,4-trichlorobenzene as mobile phase 2D-LC separations of both grafted polyolefins were realized. PMID:23474199

  3. 21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... of the total coating solids. Polyamide resins (CAS Reg. No. 68139-70-8), as the basic resin, derived... polyamide resin Ethylenediamine (CAS Reg. No. 107-15-3) Piperazine (CAS Reg. No. 110-85-0) in an amount not to exceed 6.4 percent by weight of the polyamide resin Polyamide resins, derived from...

  4. 21 CFR 175.320 - Resinous and polymeric coatings for polyolefin films.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... of the total coating solids. Polyamide resins (CAS Reg. No. 68139-70-8), as the basic resin, derived... polyamide resin Ethylenediamine (CAS Reg. No. 107-15-3) Piperazine (CAS Reg. No. 110-85-0) in an amount not to exceed 6.4 percent by weight of the polyamide resin Polyamide resins, derived from...

  5. Composites from maleated polyolefin-grafted wood particles produced via reactive extrusion

    NASA Astrophysics Data System (ADS)

    Carlborn, Karana

    This study examined the concept of using a reactive extrusion process to develop a new, formaldehyde-free binding system for wood composite products. The surfaces of wood particles were modified by grafting maleated polyethylene (MAPE) and maleated polypropylene (MAPP) compounds through a continuous reactive extrusion process. MAPE content was varied to study the effect of material composition on grafting efficiency, while extruder barrel temperatures and rotational screw speeds were varied to evaluate the effects of processing conditions on the modification of wood particles. Polymer molecular weight effects were followed using MAPP with different molecular weights. Efficiency of the modification was assessed using FTIR. 13C NMR and XPS surface analysis techniques, along with a titrimetric analysis to verify the esterification reaction between the wood particles and maleated polyolefins. Composite panels were made from wood particles modified with MAPE and MAPP binding agents under two different manufacturing methods. Specific contrasts of (i) base resin type, PE vs. PP, (ii) molecular weight/maleic anhydride content in MAPP binding agents, and (iii) the manufacturing methods (reactive extrusion vs. hot press) were investigated to determine the effects of these factors on the physico-mechanical properties of the composites. Finally, a response surface method using a Box-Behnken design was constructed to statistically model and optimize the material compositions-processing conditions-mechanical property relationships of formaldehyde-free wood composite panels. FTIR, 13C NMR, XPS and titration data confirmed the grafting of maleated polyolefins onto wood particles through an esterification reaction, while the level of grafting of MAPE onto wood particles was determined to be a function of the MAPE concentration. However, there was no significant difference in grafting efficiency at different extrusion processing conditions; rather all of the conditions resulted in

  6. Dielectric permittivity enhancement in hydroxyl functionalized polyolefins via cooperative interactions with water

    NASA Astrophysics Data System (ADS)

    Wang, C. C.; Pilania, G.; Ramprasad, R.; Agarwal, Manish; Misra, Mayank; Kumar, Sanat; Yuan, Xuepei; Mike Chung, T. C.

    2013-04-01

    Recent experiments have shown that polypropylene (PP) with a small fraction of hydroxyl (-OH) side groups displays a two-fold increase in the dielectric permittivity. It has been suggested that both the -OH groups and trapped water molecules may contribute to the dielectric constant increase. In this first principles computational study, using short polyolefin chains as models of PP, we shed light on the role played by -OH functional groups and the trapped moisture. Our results reveal that the trapped water molecules will inevitably accompany -OH incorporation (due to hydrogen bonding) and that both the -OH groups and water molecules will contribute cooperatively to the increase of the PP dielectric constant. These findings also provide insights into the effects of moisture on other molecularly functionalized materials systems.

  7. 13C and 1H NMR (Nuclear Magnetic Resonance) studies of solid polyolefines

    NASA Technical Reports Server (NTRS)

    Cudby, M. E. A.; Harris, R. K.; Metcalfe, K.; Packer, K. J.; Smith, P. W. R.

    1983-01-01

    The basis of H-1 and C-13 high-resolution NMR investigations of solid polymers is outlined. The C-13 NMR spectra of solid syndiotactic and isotactic polypropene are discussed and their interpretation in terms of conformation and chain-packing effects are reviewed. The effects of decreasing temperature on the C-13 high-resolution spectrum of an annealed sample of isotactic polypropene is described and interpreted in terms of the crystal structure. The question of the proportion of the sample giving rise to C-13 signals is addressed and some results reported. The main cause for observing only part of the total sample is shown to be the H-1 rotating frame spin-lattice relaxation behavior. The H-1 spin-lattice relaxation and spectral characteristics of a number of polyolefin samples are summarized and the role of spin-diffusion discussed.

  8. Effect of Composition and Chain Length on χ Parameter of Polyolefin Blends: A Molecular Dynamics Study

    NASA Astrophysics Data System (ADS)

    Khare, Rajesh; Ravichandran, Ashwin; Chen, Chau-Chyun

    Polymer blends exhibit complex phase behavior which is governed by several factors including temperature, composition and molecular weight of components. The thermodynamics of polymer blends is commonly described using the χ parameter. While variety of experimental studies exist on identifying the factors affecting the χ parameter, a detailed molecular scale understanding of these is a topic of current research. We have studied the effect of blend composition and chain length on χ parameter values for two model polyolefin blends. The blends studied are: polyisobutylene (PIB)/polybutadiene (PBD) and polyethylene (PE)/atactic polypropylene (aPP). Molecular dynamics simulations in combination with the integral equation theory formalism proposed by Schweizer and Curro [Journal of Chemical Physics, 91, 5059 (1989)] are used to determine the χ parameter for these systems and thereby study the effect of blend composition and chain length. The resulting χ parameter values are explained in terms of the molecular structure of these polymeric systems.

  9. Polyolefin nanocomposites

    DOEpatents

    Chaiko, David J.

    2007-01-02

    The present invention relates to methods for the preparation of clay/polymer nanocomposites. The methods include combining an organophilic clay and a polymer to form a nanocomposite, wherein the organophilic clay and the polymer each have a peak recrystallization temperature, and wherein the organophilic clay peak recrystallization temperature sufficiently matches the polymer peak recrystallization temperature such that the nanocomposite formed has less permeability to a gas than the polymer. Such nanocomposites exhibit 2, 5, 10, or even 100 fold or greater reductions in permeability to, e.g., oxygen, carbon dioxide, or both compared to the polymer. The invention also provides a method of preparing a nanocomposite that includes combining an amorphous organophilic clay and an amorphous polymer, each having a glass transition temperature, wherein the organophilic clay glass transition temperature sufficiently matches the polymer glass transition temperature such that the nanocomposite formed has less permeability to a gas than the polymer.

  10. Semicrystalline thermoplastic elastomeric polyolefins: Advances through catalyst development and macromolecular design

    PubMed Central

    Hotta, Atsushi; Cochran, Eric; Ruokolainen, Janne; Khanna, Vikram; Fredrickson, Glenn H.; Kramer, Edward J.; Shin, Yong-Woo; Shimizu, Fumihiko; Cherian, Anna E.; Hustad, Phillip D.; Rose, Jeffrey M.; Coates, Geoffrey W.

    2006-01-01

    We report the design, synthesis, morphology, phase behavior, and mechanical properties of semicrystalline, polyolefin-based block copolymers. By using living, stereoselective insertion polymerization catalysts, syndiotactic polypropylene-block-poly(ethylene-co-propylene)-block-syndiotactic polypropylene and isotactic polypropylene-block-regioirregular polypropylene-block-isotactic polypropylene triblock copolymers were synthesized. The volume fraction and composition of the blocks, as well as the overall size of the macromolecules, were controlled by sequential synthesis of each block of the polymers. These triblock copolymers, with semicrystalline end-blocks and mid-segments with low glass-transition temperatures, show significant potential as thermoplastic elastomers. They have low Young's moduli, large strains at break, and better than 90% elastic recovery at strains of 100% or less. An isotactic polypropylene-block-regioirregular polypropylene-block-isotactic polypropylene-block-regioirregular polypropylene-block-isotactic polypropylene pentablock copolymer was synthesized that also shows exceptional elastomeric properties. Notably, microphase separation is not necessary in the semicrystalline isotactic polypropylenes to achieve good mechanical performance, unlike commercial styrenic thermoplastic elastomers. PMID:17032769

  11. Programmed-life plastics from polyolefins: a new look at sustainability.

    PubMed

    Scott, G; Wiles, D M

    2001-01-01

    The term "sustainable" is often assumed to be synonymous with "renewable". However, polymers made from renewable natural resources are not necessarily eco-efficient. Cellulose-based polymers utilize more nonrenewable fossil fuels and are more polluting during manufacture than petro-based polymers. Sustainable polymers also have to be industrially acceptable, and although ultimate biodegradability in the natural environment is important, polymer-based products are required to biodegrade in a controlled way. Service life may be a year or more before the commencement of environmental degradation occurs. Many natural polymers such as rubber, lignin, and humus, like the synthetic polyolefins, biodegrade by an oxidative mechanism (oxo-biodegradation), and consequently much of nature's biological waste cannot satisfy the rapid mineralization criteria currently advocated by standards committees for synthetic polymers. Although biometric tests are more convenient to use than full composting tests, they are meaningless when applied to hydrocarbon polymers, whether natural or synthetic, since oxo-biodegradation is a slower process than hydro-biodegradation at ambient temperatures. Biodegradation standards currently proposed are unrealistic and will need to be modified on the basis of recent scientific evidence. PMID:11710012

  12. Incompatibilities of lornoxicam with 4 antiemetic medications in polyolefin bags during simulated intravenous administration.

    PubMed

    Fang, Bao-Xia; Li, Peng; Shi, Xiao-Ya; Chen, Fu-Chao; Wang, Lin-Hai

    2016-06-01

    The administration of drugs by patient-controlled analgesia (PCA) is routinely practiced for the management of postoperative pain. It is common for 2 or more drugs to be combined in PCA solutions. The combination of analgesics and antiemetic agents is frequently required. Unfortunately, the compatibility and stability of lornoxicam and antiemetic agents, such as droperidol, ondansetrone, granisetron, and tropisetron, has not been determined. The aim of this study was to evaluate the compatibility and stability of solutions containing lornoxicam with the 4 antiemetic agents in combination for PCA administration.In our study, test samples were prepared in triplicate by adding 40 mg lornoxicam and 5 mg droperidol, 8 mg ondansetron, 6 mg granisetron, or 5 mg tropisetron to 100-mL polyolefin bags of sodium chloride 0.9% and stored at 25 °C. The analgesic mixture samples were visually inspected for precipitation, cloudiness, and discoloration at each sampling interval. Drug concentrations were determined using high-performance liquid chromatographic (HPLC) analysis.No loss of lornoxicam occurred with any of the 4 antiemetic agents tested for up to 48 hours. However, the contents of droperidol, ondansetron, granisetron, and tropisetron were significant loss >48 hours. After storage of 4.0 to 48.0 hours, the presence of a slight precipitate was observed in all the injection combinations.The results indicate that combinations of lornoxicam with droperidol, ondansetrone, granisetron, or tropisetron in infusion solution during simulated intravenous PCA administration were incompatibility when stored protected from light at 25 °C. PMID:27336868

  13. Nitrate leaching and nitrogen recovery following application of polyolefin-coated urea to potato.

    PubMed

    Zvomuya, Francis; Rosen, Carl J; Russelle, Michael P; Gupta, Satish C

    2003-01-01

    High N fertilizer and irrigation amounts applied to potato (Solanum tuberosum L.) on coarse-textured soils often result in nitrate (NO3) leaching and low recovery of applied fertilizer N. This 3-yr study compared the effects of two rates (140 and 280 kg N ha(-1)) of a single polyolefin-coated urea (PCU) application versus split applications of urea on 'Russet Burbank' potato yield and on NO3 leaching and N recovery efficiency (RE) on a loamy sand. Standard irrigation was applied in all years and excessive irrigation was used in another experiment in the third year. At the recommended rate of 280 kg N ha(-1), NO3 leaching during the growing season was 34 to 49% lower with PCU than three applications of urea. Under standard irrigation in the third year, leaching from five applications of urea (280 kg N ha(-1)) was 38% higher than PCU. Under leaching conditions in the first year (> or = 25 mm drainage water in at least one 24-h period) and excessive irrigation in the third year, PCU at 280 kg N ha(-1) improved total and marketable tuber yields by 12 to 19% compared with three applications of urea. Fertilizer N RE estimated by the difference and 15N isotope methods at the 280 kg N ha(-1) rate was, on average, higher with PCU (mean 50%) than urea (mean 43%). Fertilizer N RE values estimated by the isotope method (mean 51%) were greater than those estimated by the difference method (mean 47%). Results from this study indicate that PCU can reduce leaching and improve N recovery and tuber yield during seasons with high leaching. PMID:12708671

  14. Application of NIR hyperspectral imaging for post-consumer polyolefins recycling

    NASA Astrophysics Data System (ADS)

    Serranti, Silvia; Gargiulo, Aldo; Bonifazi, Giuseppe

    2012-06-01

    An efficient large-scale recycling approach of particulate solid wastes is always accomplished according to the quality of the materials fed to the recycling plant and/or to any possible continuous and reliable control of the different streams inside the processing plants. Processing technologies addressed to recover plastics need to be extremely powerful, since they must be relatively simple to be cost-effective, but also accurate enough to create high-purity products and able to valorize a substantial fraction of the plastic waste materials into useful products of consistent quality in order to be economical. On the other hand, the potential market for such technologies is large and the boost of environmental regulations, and the oil price increase, has made many industries interested both in "general purpose" waste sorting technologies, as well as in developing more specialized sensing devices and/or inspection logics for a better quality assessment of plastic products. In this perspective recycling strategies have to be developed taking into account some specific aspects as i) mixtures complexity: the valuable material has to be extracted from the residue, ii) overall production: the profitability of plastic can be achieved only with mass production and iii) costs: low-cost sorting processes are required. In this paper new analytical strategies, based on hyperspectral imaging in the near infrared field (1000-1700 nm), have been investigated and set up in order to define sorting and/or quality control logics that could be profitably applied, at industrial plant level, for polyolefins recycling.

  15. Incompatibilities of lornoxicam with 4 antiemetic medications in polyolefin bags during simulated intravenous administration

    PubMed Central

    Fang, Bao-xia; Li, Peng; Shi, Xiao-ya; Chen, Fu-chao; Wang, Lin-hai

    2016-01-01

    Abstract The administration of drugs by patient-controlled analgesia (PCA) is routinely practiced for the management of postoperative pain. It is common for 2 or more drugs to be combined in PCA solutions. The combination of analgesics and antiemetic agents is frequently required. Unfortunately, the compatibility and stability of lornoxicam and antiemetic agents, such as droperidol, ondansetrone, granisetron, and tropisetron, has not been determined. The aim of this study was to evaluate the compatibility and stability of solutions containing lornoxicam with the 4 antiemetic agents in combination for PCA administration. In our study, test samples were prepared in triplicate by adding 40 mg lornoxicam and 5 mg droperidol, 8 mg ondansetron, 6 mg granisetron, or 5 mg tropisetron to 100-mL polyolefin bags of sodium chloride 0.9% and stored at 25 °C. The analgesic mixture samples were visually inspected for precipitation, cloudiness, and discoloration at each sampling interval. Drug concentrations were determined using high-performance liquid chromatographic (HPLC) analysis. No loss of lornoxicam occurred with any of the 4 antiemetic agents tested for up to 48 hours. However, the contents of droperidol, ondansetron, granisetron, and tropisetron were significant loss >48 hours. After storage of 4.0 to 48.0 hours, the presence of a slight precipitate was observed in all the injection combinations. The results indicate that combinations of lornoxicam with droperidol, ondansetrone, granisetron, or tropisetron in infusion solution during simulated intravenous PCA administration were incompatibility when stored protected from light at 25 °C. PMID:27336868

  16. Heterogeneous polymer modification: Polyolefin maleation in supercritical carbon dioxide and amorphous fluoropolymer surface modification

    NASA Astrophysics Data System (ADS)

    Hayes, Heather J.

    1999-11-01

    Three distinct heterogeneous polymer modification reactions are explored in this work. The first is a bulk reaction commonly conducted on polyolefins---the free radical addition of maleic anhydride. This reaction was run using supercritical carbon dioxide (SC CO2) as the solvent. The second was the chemical surface modification of an amorphous fluorocopolymer of tetrafluoroethylene and a perfluorodioxole monomer (Teflon AF). Several reactions were explored to reduce the surface of the fluorocopolymer for the enhancement of wettability. The last modification was also on Teflon AF and involved the physical modification of the surface through the transport polymerization of xylylene in order to synthesize a novel bilayer membrane. The bulk maleation of poly-4-methyl-1-pentene (PMP) was the focus of the first project. SC CO2 was utilized as both solvent and swelling agent to promote this heterogeneous reaction and led to successful grafting of anhydride groups on both PMP and linear low density polyethylene. Varying the reaction conditions and reagent concentrations allowed optimization of the reaction. The grafted anhydride units were found to exist as single maleic and succinic grafts, and the PMP became crosslinked upon maleation. The surface of a fluoropolymer can be difficult to alter. An examination of three reactions was made to determine the reactivity of Teflon AF: sodium naphthalenide treatment (Na-Nap), aluminum metal modification through deposition and dissolution, and mercury/ammonia photosensitization. The fluorocopolymer with the lower perfluorodioxole percentage was found to be more reactive towards modification with the Na-Nap treatment. The other modification reactions appeared to be nearly equally reactive toward both fluorocopolymers. The functionality of the Na-Nap-treated surface was examined in detail with the use of several derivatization reactions. In the final project, an asymmetric gas separation membrane was synthesized using Teflon AF as

  17. Nonlinear rheology and strain recovery of short chain branched polyolefin elastomers and thermoplastic olefin blends

    NASA Astrophysics Data System (ADS)

    Patham, Bhaskar

    Polyolefin elastomers are random copolymers having a polyethylene backbone with the higher olefinic comonomer incorporated as short-chain branches. These random copolymers are widely used as polymer modifiers for thermoplastic materials such as polypropylenes, resulting in thermoplastic olefin (TPO) blends. This thesis addresses the nonlinear rheological behavior of the elastomers and then of the TPO blends. The effects of varying short chain branch density (SCB) on the melt rheology of three ethylene-octene random copolymers have been investigated. In particular, the strain-hardening behavior in extensional flow and strain recovery following nonlinear shear creep has been evaluated. The zero-shear viscosity followed trends in the backbone molecular weight closely. While the three copolymers were indistinguishable in linear viscoelastic creep and recovery, recovery following nonlinear shear creep decreased progressively with increasing SCB density. This reveals that the extent of rapid chain equilibration that occurs over Rouse time scales at higher strains was progressively lower with increasing SCB density. Strain hardening in uniaxial extensional flow was observed for all three copolymers. At strain rates below the primitive chain equilibration rates, strain hardening increases progressively with increasing SCB density. At higher rates, upon onset of primitive chain stretch, the strain hardening behavior for the three melts merges. Two thermoplastic olefin (TPO) blends were characterized in the context of injection molding; the surface morphology of injection molded tensile bars with these materials showed surface defects or flow marks to different extents. The flow marks were traced to different degrees of strain recovery in the dispersed phases of the two blends. This recovery occurred over injection molding timescales of the order of a few seconds. Strain recovery after shear creep was higher in the blend that displayed more severe flow marks in injection

  18. The use of thermovision technique to estimate the properties of highly filled polyolefins composites with calcium carbonate

    SciTech Connect

    Jakubowska, Paulina; Klozinski, Arkadiusz

    2015-05-22

    The aim of this work was to determine the possibility of thermovision technique usage for estimating thermal properties of ternary highly filled composites (PE-MD/iPP/CaCO{sub 3}) and polymer blends (PE-MD/iPP) during mechanical measurements. The ternary, polyolefin based composites that contained the following amounts of calcium carbonate: 48, 56, and 64 wt % were studied. All materials were applying under tensile cyclic loads (x1, x5, x10, x20, x50, x100, x500, x1000). Simultaneously, a fully radiometric recording, using a TESTO infrared camera, was created. After the fatigue process, all samples were subjected to static tensile test and the maximum temperature at break was also recorded. The temperature values were analyzed in a function of cyclic loads and the filler content. The changes in the Young’s modulus values were also investigated.

  19. [Pollution Characteristics and Light Extinction Effects of Water-soluble Ions in PM2.5 During Winter Hazy Days at North Suburban Nanjing].

    PubMed

    Zhou, Yao-yao; Ma, Yan; Zheng, Jun; Cui, Fen-ping; Wang, Li

    2015-06-01

    To investigate the characteristics of water-soluble ions in PM2.5 and their contribution to light extinction in haze days, on-line monitoring of PM2.5. was conducted at North Suburban Nanjing from 25 January through 3 February, 2013. Water-soluble components were collected with a particle-into-liquid sampler (PILS), and analyzed by ion chromatography (IC) for the contents of SO4(2-), NO3-, NH4+, Cl-, Na+, K+, Mg2+ and Ca2+ Simultaneously particle size distributions were measured using scanning mobility particle sizer (SMPS) and Aerodynamic Particle Sizer (APS). The absorption and scattering coefficients were measured by three-wavelength photoacoustic soot spectrometer (PASS-3). Trace gases (SO2, NO2 etc.) were also monitored. The results showed that the average concentrations of total water-soluble ions were 70.3 and 22.9 microg x m(-3) in haze and normal days, respectively. Secondary hygroscopic components including SO4(2-), NO3- and NH4+ were the major ionic pollutants. Hazy days favored the conversion of SO2 and NOx, to SO4(2-) and NO3-, respectively, and in particular the oxidation of NOx. Using multiple linear regression statistical method, the empirical relationship between the dry aerosol extinction coefficient and the chemical composition was established. NH4NO3 was found to be the largest contributor to aerosol extinction in winter in Nanjing, followed by (NH4)2SO4, OC and EC. In two heavy pollution events, the increase of ion concentrations was influenced by the increase of primary emissions and secondary transformation. PMID:26387291

  20. Stability of tramadol with three 5-HT3 receptor antagonists in polyolefin bags for patient-controlled delivery systems

    PubMed Central

    Chen, Fu-chao; Zhu, Jun; Li, Bin; Yuan, Fang-jun; Wang, Lin-hai

    2016-01-01

    Background Mixing 5-hydroxytryptamine-3 (5-HT3) receptor antagonists with patient-controlled analgesia (PCA) solutions of tramadol has been shown to decrease the incidence of nausea and vomiting associated with the use of tramadol PCA for postoperative pain. However, such mixtures are not commercially available, and the stability of the drug combinations has not been duly studied. The study aimed to evaluate the stability of tramadol with three 5-HT3 receptor antagonists in 0.9% sodium chloride injection for PCA administration. Materials and methods Test samples were prepared by adding 1,000 mg tramadol hydrochloride, 8 mg ondansetron hydrochloride, and 6 mg granisetron hydrochloride or 5 mg tropisetron hydrochloride to 100 mL of 0.9% sodium chloride injection in polyolefin bags. The samples were prepared in triplicates, stored at either 25°C or 4°C for 14 days, and assessed using the following compatibility parameters: precipitation, cloudiness, discoloration, and pH. Chemical stability was also determined using a validated high-pressure liquid chromatography method. Results All of the mixtures were clear and colorless throughout the initial observation period. No change in the concentration of tramadol hydrochloride occurred with any of the 5-HT3 receptor antagonists during the 14 days. Similarly, little or no loss of the 5-HT3 receptor antagonists occurred over the 14-day period. Conclusion Our results suggest that mixtures of tramadol hydrochloride, ondansetron hydrochloride, granisetron hydrochloride, or tropisetron hydrochloride in 0.9% sodium chloride injection were physically and chemically stable for 14 days when stored in polyolefin bags at both 4°C and 25°C. PMID:27350741

  1. Analysis of saturated and aromatic hydrocarbons migrating from a polyolefin-based hot-melt adhesive into food.

    PubMed

    Lommatzsch, Martin; Biedermann, Maurus; Grob, Koni; Simat, Thomas J

    2016-03-01

    Hot-melt adhesives are widely utilised to glue cardboard boxes used as food packaging material. They have to comply with the requirements of Article 3 of the European Framework Regulation for food contact materials (1935/2004). The hot melt raw materials analysed mainly consisted of paraffinic waxes, hydrocarbon resins and polyolefins. The hydrocarbon resins, functioning as tackifiers, were the predominant source of hydrocarbons of sufficient volatility to migrate into dry foods: the 18 hydrocarbon resins analysed contained 8.2-118 g kg(-1) saturated and up to 59 g kg(-1) aromatic hydrocarbons eluted from GC between n-C16 and n-C24, substantially more than the paraffinic waxes and the polyolefins. These tackfier resins, especially the oligomers ≤ C24, have been characterised structurally by GC×GC-MS and (1)H-NMR spectroscopy. Migration into food was estimated using a simulating system with polenta as food simulant, which was verified by the analysis of a commercial risotto rice sample packed in a virgin fibre folding box sealed with a hot melt. About 0.5-1.5% of the potentially migrating substances (between n-C16 and n-C24) of a hot melt were found to be transferred into food under storage conditions, which can result in a food contamination in the order of 1 mg kg(-1) food (depending on the amount of potentially migrating substances from the hot melt, the hot melt surface, amount of food, contact time etc.). Migrates from hot melts are easily mistaken for mineral oil hydrocarbons from recycled cardboard. PMID:26744923

  2. Synthesis of chain-end functionalized polyolefins and fluoropolymers and applications in nanocomposites

    NASA Astrophysics Data System (ADS)

    Wang, Zhiming

    temperature of 75°C, the high concentration of hydrogen suppresses catalytic activity. The chain ends consist of predominately terminal p-MS and a small amount of unsaturated end groups. A higher p-MS concentration or introduction of hydrogen eliminates the undesirable unsaturated chain ends. Furthermore, we also study a new chemical route to prepared side chain functionalized polyolefin, especially the desirable MA (maleic anhydride) -modified PE and PP polymers with well-controlled molecular structures. The chemistry involves a post-polymerization process using borane/O2 stable radical initiators to create polymeric radicals that are simultaneously stabilized by in situ formed *O-BR2 stable radicals. The dormant polymeric radicals do not undergo undesirable side reactions (crosslinking and degradation, etc.), but can react with maleic anhydride. Some MAH-modified PP polymers with high molecular weight and controlled MAH content have been obtained. They have been proven to be the effective compatibilizers to improve the interfacial adhesion in the PP/Nylon 11 blends. (Abstract shortened by UMI.)

  3. Acute Degradation of Surface-Bound Unsaturated Polyolefins in Common Solvents under Ambient Conditions

    PubMed Central

    Lerum, Maria Felisa Z.; Chen, Wei

    2009-01-01

    We describe the detachment of covalently grafted polybutadiene and polynorbornenechains – which were prepared by surface-initiated ring-opening metathesis polymerization (SiROMP) – from Si/SiO2 substrates upon brief exposure to common solvents in air. Degradation and disappearance of grafted polybutadiene films after successive rinses with dichloromethane was monitored by ellipsometry. Changes in surface topography were analyzed by atomic force microscopy. The rapid auto-oxidation of allylic carbon-hydrogen bonds renders these thin films extremely susceptible to degradation under ambient conditions. Polymers in the tethered state suffer more acute degradation (on the time scale of seconds) compared to those dissolved in solution (not detectable after days). To prevent degradation, unsaturated polymersprepared by SiROMP and the subsequent conversion (of unsaturated groups) need to be carriedout under inert atmosphere. For example, smooth polybutadiene thin films of ~ 100 Å thick were covalently attached to silicon substrates via SiROMP of cyclooctadiene in the vapor phase. Solvent rinsing to remove unreacted monomers and free oligomers/polymers was carried out prior to the conversion of double bonds to epoxide groups. When these steps were carried out under nitrogen, negligible film loss was observed and surface topography of the thin film was preserved. Once the unsaturation was removed from polybutadiene, the epoxidized and hydroxylated polybutadiene films were stable toward solvent exposure in air. PMID:19788207

  4. Adhesive for solar control film

    SciTech Connect

    Penn, H.J.

    1984-01-31

    A water-activatable adhesive useful for adhering a solar film, polyester (polyethylene terephthalate) film, to glass or to metal substrates. The adhesive comprises the reacted product of (A) gamma-isocyanatopropyltriethoxy silane, containing a free isocyanate (NCO) group, and (B) a thermoplastic polyester formed by reacting (i) a dibasic acid selected from the group consisting of terephthalic acid, isophthalic acid and hexahydrophthalic acid, and mixtures thereof, with (ii) a polymethylene glycol of the formula HO(CH/sub 2/) /SUB x/ OH where x is an integer from 2 to 10, neopentyl glycol and glycerin, and mixtures thereof, and (iii) an aliphatic dibasic acid selected from the group consisting of those having the formula HOOC(CH/sub 2/) /SUB n/ COOH where n is an integer from 1 to 8, and mixtures of such acids, whereby substantially no free NCO remains in the adhesive. Solar film is used for absorbing and/or reflecting solar radiation. Solar film can be a single sheet of polyester dyed sufficiently to absorb the glare of bright sunlight, or it can be a single sheet of polyester, on one side of which a reflective metal (most often aluminum) is deposited in an amount which can be totally reflective or in an amount which still allows visible light transmission and over which a protective coating is deposited, or it can be a laminated structure of the reflective film adhered to a clear or dyed polyester film by which means the reflective metal is sandwiched between two layers of polyester film, or it can be a laminated structure of a reflective film to a polyolefin film.

  5. Use of Taylor Rod-on-Anvil Impact Experiments to Investigate High Strain Rate Behaviour in Polyolefins

    NASA Astrophysics Data System (ADS)

    Bucknall, David; Luce, Amanda; Kannan, Abhiram; Breidenich, Jennifer; Thadhani, Naresh

    2015-06-01

    The high strain rate deformation and mechano-lumination of various polyethylenes and polypropylene is studied using Taylor rod-on-anvil impact testing. Polypropylene and low density (LDPE), high density (HDPE), and ultra high molecular weight (UHMWPE) polyethylene samples were impacted against a hardened steel anvil at velocities ranging from 50-500 m/s. High-speed imaging, time-resolved spectroscopy, and thermal imaging are employed to track the macroscopic shape change and observe mechano-lumination and heating during impact. Additionally, electron spin resonance (ESR) and gel permeation chromatography (GPC) measurements were performed on recovered impacted samples to explain the observed deformation behavior in the various polyolefins. Time-resolved spectroscopy, coupled with ESR and GPC measurements indicate that chain scission occurs during the first few microseconds of the impact event. The observed macroscopic deformation that occurs after the observed mechano-illumination event is therefore influenced by the loss of mechanical strength associated with a drop in the molecular weight of the polymer.

  6. Polylactic acid/zinc oxide biocomposite films for food packaging application.

    PubMed

    Marra, Antonella; Silvestre, Clara; Duraccio, Donatella; Cimmino, Sossio

    2016-07-01

    Although PLA is much more expensive than polyolefins, such as PP and PE, there is a great interest to propose PLA based material as alternative films for food packaging being PLA derivable from natural source, compostable and biodegradable. For this purpose the research has the task to investigate and propose PLA materials with enhanced properties to be effectively and efficiently alternative to polyolefin films for food packaging application. In this contribution, biocomposite films of PLA with 1, 3 and 5wt% of ZnO have been investigated to determine mechanical, barrier and antimicrobial (against Escherichia coli) properties. It is found that the biocomposite films are characterized by a good dispersion of the ZnO particles in PLA matrix, although no previous treatment was performed on ZnO particles, such as silanization, to decrease its incompatibility with the polymer. The biocomposite films have shown good mechanical properties, decrease of permeability to CO2 and O2, and only a slight increase to water vapour. Particularly important is that, for the biocomposite with 5wt% of ZnO, the % Reduction for E. Coli test reached the value of 99.99 already after 24h. PMID:27012896

  7. Surface characteristics of PLA and PLGA films

    NASA Astrophysics Data System (ADS)

    Paragkumar N, Thanki; Edith, Dellacherie; Six, Jean-Luc

    2006-12-01

    Surface segregation and restructuring in polylactides (poly( D, L-lactide) and poly( L-lactide)) and poly( D,L-lactide-co-glycolide) (PLGA) films of various thicknesses were investigated using both attenuated total reflection FTIR (ATR-FTIR) and contact angle relaxation measurements. In case of poly( D,L-lactide) (DLPLA), it was observed that the surface segregation and the surface restructuring of methyl side groups are influenced by the polymer film thickness. This result has been confirmed by X-ray photoelectron spectroscopy (XPS). In the same way, PLGA thick films were also characterized by an extensive surface segregation of methyl side groups. Finally, surface restructuring was investigated by dynamic contact angle measurements and it was observed when film surface comes into contact with water. In parallel, we also found that poly( L-lactide) (PLLA) thin and clear films with thickness ˜15 μm undergo conformational changes on the surface upon solvent treatment with certain solvents. The solvent treated surface of PLLA becomes hazy and milky white and its hydrophobicity increases compared to untreated surface. FTIR spectroscopic analysis indicated that polymer chains at the surface undergo certain conformational changes upon solvent treatment. These changes are identified as the restricted motions of C-O-C segments and more intense and specific vibrations of methyl side groups. During solvent treatment, the change in water contact angle and FTIR spectrum of PLLA is well correlated.

  8. Unimpeded permeation of water through biocidal graphene oxide sheets anchored on to 3D porous polyolefinic membranes

    NASA Astrophysics Data System (ADS)

    Mural, Prasanna Kumar S.; Jain, Shubham; Kumar, Sachin; Madras, Giridhar; Bose, Suryasarathi

    2016-04-01

    3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and hot-pressed samples revealed a clear picture as to how the morphology develops and coarsens over a function of time during post-processing operations like compression molding. The coarsening of PE/PEO blends was traced using X-ray micro-computed tomography and scanning electron microscopy (SEM) of annealed blends at different times. It is now understood from X-ray micro-computed tomography that by the addition of a compatibilizer (here lightly maleated PE), a stable morphology can be visualized in 3D. In order to anchor biocidal graphene oxide sheets onto these 3D porous membranes, the PE membranes were chemically modified with acid/ethylene diamine treatment to anchor the GO sheets which were further confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and surface Raman mapping. The transport properties through the membrane clearly reveal unimpeded permeation of water which suggests that anchoring GO on to the membranes does not clog the pores. Antibacterial studies through the direct contact of bacteria with GO anchored PE membranes resulted in 99% of bacterial inactivation. The possible bacterial inactivation through physical disruption of the bacterial cell wall and/or reactive oxygen species (ROS) is discussed herein. Thus this study opens new avenues in designing polyolefin based antibacterial 3D porous membranes for water purification.3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and

  9. Unimpeded permeation of water through biocidal graphene oxide sheets anchored on to 3D porous polyolefinic membranes.

    PubMed

    Mural, Prasanna Kumar S; Jain, Shubham; Kumar, Sachin; Madras, Giridhar; Bose, Suryasarathi

    2016-04-14

    3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and hot-pressed samples revealed a clear picture as to how the morphology develops and coarsens over a function of time during post-processing operations like compression molding. The coarsening of PE/PEO blends was traced using X-ray micro-computed tomography and scanning electron microscopy (SEM) of annealed blends at different times. It is now understood from X-ray micro-computed tomography that by the addition of a compatibilizer (here lightly maleated PE), a stable morphology can be visualized in 3D. In order to anchor biocidal graphene oxide sheets onto these 3D porous membranes, the PE membranes were chemically modified with acid/ethylene diamine treatment to anchor the GO sheets which were further confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and surface Raman mapping. The transport properties through the membrane clearly reveal unimpeded permeation of water which suggests that anchoring GO on to the membranes does not clog the pores. Antibacterial studies through the direct contact of bacteria with GO anchored PE membranes resulted in 99% of bacterial inactivation. The possible bacterial inactivation through physical disruption of the bacterial cell wall and/or reactive oxygen species (ROS) is discussed herein. Thus this study opens new avenues in designing polyolefin based antibacterial 3D porous membranes for water purification. PMID:27020773

  10. Stability-indicating HPLC method for the determination of the stability of oxytocin parenteral solutions prepared in polyolefin bags.

    PubMed

    Kaushal, G; Sayre, B E; Prettyman, T

    2012-02-01

    Oxytocin is very commonly used in clinical settings and is a nonapeptide hormone that stimulates the contraction of uterine smooth muscles. In this study the stability of extemporaneously compounded oxytocin solutions was investigated in polyolefin bags. The sterile preparations of oxytocin were compounded to the strength of 0.02 U/mL in accordance with United States Pharmacopeia (USP) <797> standards. In order to carry out the stability testing of these parenteral products, the solutions were stored under three different temperature conditions of -20°C (frozen), 2-6°C (refrigerated), and 22-25°C (room temperature). Three solutions from each temperature were withdrawn and were assessed for stability on days 0, 7, 15, 21, and 30 as per the USP guidelines. The assay of oxytocin was examined by an HPLC method at each time point. No precipitation, cloudiness or color change was observed during this study at all temperatures. The assay content by HPLC revealed that oxytocin retains greater than at least 90% of the initial concentrations for 21 days. There was no significant change in pH and absorbance values for 21 days under all the conditions of storage. Oxytocin parenteral solutions in the final concentration of 0.02 U/mL and diluted in normal saline are stable for at least 30 days under frozen and refrigerated conditions for 30 days. At the room temperature, the oxytocin solutions were stable for at least 21 days. The stability analysis results show that the shelf-life of 21 days observed in this study was far better than their recommended expiration dates. PMID:22460429

  11. Nanosized carbon black combined with Ni2O3 as "universal" catalysts for synergistically catalyzing carbonization of polyolefin wastes to synthesize carbon nanotubes and application for supercapacitors.

    PubMed

    Wen, Xin; Chen, Xuecheng; Tian, Nana; Gong, Jiang; Liu, Jie; Rümmeli, Mark H; Chu, Paul K; Mijiwska, Ewa; Tang, Tao

    2014-04-01

    The catalytic carbonization of polyolefin materials to synthesize carbon nanotubes (CNTs) is a promising strategy for the processing and recycling of plastic wastes, but this approach is generally limited due to the selectivity of catalysts and the difficulties in separating the polyolefin mixture. In this study, the influence of nanosized carbon black (CB) and Ni2O3 as a novel combined catalyst system on catalyzing carbonization of polypropylene (PP), polyethylene (PE), polystyrene (PS) and their blends was investigated. We showed that this combination was efficient to promote the carbonization of these polymers to produce CNTs with high yields and of good quality. Catalytic pyrolysis and model carbonization experiments indicated that the carbonization mechanism was attributed to the synergistic effect of the combined catalysts rendered by CB and Ni2O3: CB catalyzed the degradation of PP, PE, and PS to selectively produce more aromatic compounds, which were subsequently dehydrogenated and reassembled into CNTs via the catalytic action of CB together with Ni particles. Moreover, the performance of the synthesized CNTs as the electrode of supercapacitor was investigated. The supercapacitor displayed a high specific capacitance as compared to supercapacitors using commercial CNTs and CB. This difference was attributed to the relatively larger specific surface areas of our synthetic CNTs and their more oxygen-containing groups. PMID:24611910

  12. Analysis of low levels of oxygen, carbon monoxide, and carbon dioxide in polyolefin feed streams using a pulsed discharge detector and two PLOT columns.

    PubMed

    Wurm, David B; Sun, Kefu; Winniford, William L

    2003-01-01

    A gas chromatography (GC) method is developed for rapid analysis of polyolefin feed streams for the catalyst poisons CO, CO(2), and O(2). The method uses an HP MoleSieve column in parallel with a CP-PoraPLOT Q column and a pulsed discharge detector (PDD). Detection limits for each of the potential poisons are between 50 and 250 ppb. For a 10-ppm standard, the precision of the method was +/- 4.2% for oxygen, +/- 7.8% for carbon dioxide, and +/- 2.0% for carbon monoxide. In addition to the polyolefin feed stream, nitrogen and hydrogen feed streams are also analyzed. In each case, sampling is observed to be a critical issue, with air contamination of the sample cylinder often the limiting step in determining the true level of oxygen. It is also noted that large amounts of argon are present in the standards when nitrogen is used as a balance gas. Because the trace oxygen peak partly coelutes with the larger argon peak, it is suggested that helium be used as the balance gas for all standards. This general experimental arrangement should be effective when applied to feed streams for other polymers as well. PMID:14629793

  13. Mechanical behavior and essential work of fracture of starch-based blown films

    NASA Astrophysics Data System (ADS)

    Nottez, M.; Chaki, S.; Soulestin, J.; Lacrampe, M. F.; Krawczak, P.

    2015-05-01

    A fracture mechanics approach (Essential Work of Fracture, EWF) was applied to assess the toughness of novel partly starch-grafted polyolefin blown films, compared to that of a neat polyethylene reference. Tests were performed on double-end notched samples. The digital image correlation method was used to monitor the deformation field around the notch. Regular tensile and tear tests were also carried out. The specific essential work of fracture is a characteristic which is much more sensitive to materials structural modifications than the tensile or tear properties.

  14. Development of high temperature comprehensive two-dimensional liquid chromatography hyphenated with infrared and light scattering detectors for characterization of chemical composition and molecular weight heterogeneities in polyolefin copolymers.

    PubMed

    Lee, D; Miller, M D; Meunier, D M; Lyons, J W; Bonner, J M; Pell, R J; Shan, C Li Pi; Huang, T

    2011-10-01

    The application of high temperature comprehensive two-dimensional (2D) liquid chromatography for quantitative characterization of chemical composition and molecular weight (MW) heterogeneities in polyolefins is demonstrated in this study by separating a physical blend of isotactic-polypropylene, ethylene-random-propylene copolymer, and high density polyethylene. The first dimension separation is based on adsorption liquid chromatography that fractionates the blend from low to high ethylene content. The second dimension is size-exclusion chromatography connected with light scattering (LS) and infrared (IR) detectors. The IR detector shows desired sensitivity and linearity for monitoring analyte concentrations in the eluent after 2D separations. In addition, the compositions of the analytes are also determined from the ratio of two IR absorbances at the specified wavelength regions, an absorbance for measuring the level of methyl groups in polyolefins and another absorbance for measuring concentration. The LS detector is used to determine absolute molecular weight of the analytes from the ratio of the light scattering signal to the IR concentration signal. The ability to obtain concentration, chemical composition, and MW of polyolefins after 2D separation provides new opportunities to discover structure-property relationships for polyolefins with complex structures/architectures. PMID:21880320

  15. Long-term stability of morphine hydrochloride in 0.9% NaCl infusion polyolefin bags after freeze-thaw treatment and in polypropylene syringes at 5 degrees C + 3 degrees C.

    PubMed

    Hecq, J-D; Godet, M; Gillet, P; Jamart, J; Galanti, L

    2014-01-01

    The aim of this study was to investigate the long-term stability of morphine hydrochloride in 0.9% NaCI infusion polyolefin bags and polypropylene syringes after storage at 5 degrees C + 3 degrees C and to evaluate the influence of initial freezing and microwave thawing on this stability. Ten polyolefin bags and five polypropylene syringes containing 100 mL of 1 mg/mL of morphine hydrochloride solution in 0.9% NaCI were prepared under aseptic conditions. Five polyolefin bags were frozen at -20 degrees C for 90 days before storage. Immediately after the preparation and after thawing, 2 mL of each bag were withdrawn for the initial concentration measurements. All polyolefin bags and polypropylene syringes were then refrigerated at 5 degrees C + 3 degrees C for 58 days during which the morphine concentrations were measured periodically by high-performance liquid chromatography using a reversed-phase column, naloxone as internal standard, a mobile phase consisting of 5% acetonitrile and 95% of KH2PO4 buffer (pH 3.50), and detection with diode array detector at 254 nm. Visual and microscopic observations and spectrophotometric and pH measurements were also performed. Solutions were considered stable if the concentration remained superior to 90% of the initial concentration. The degradation products peaks were not quantitatively significant and were resolved from the native drug. Polyolefin bag and polypropylene syringe solutions were stable when stored at 5 degrees C + 3 degrees C during these 58 days. No color change or precipitation in the solutions was observed. The physical stability was confirmed by visual, microscopic, and spectrophotometric inspection. There was no significant change in pH during storage. Freezing and microwave thawing didn't influence the infusion stability. Morphine hydrochloride infusions may be prepared in advance by centralized intravenous additive service, frozen in polyolefin bags, and microwave thawed before storage under refrigeration

  16. Super hydrogen and helium barrier with polyelectolyte nanobrick wall thin film.

    PubMed

    Tzeng, Ping; Lugo, Elva L; Mai, Garret D; Wilhite, Benjamin A; Grunlan, Jaime C

    2015-01-01

    In an effort to impart light gas (i.e., H2 and He) barrier to polymer substrates, thin films of polyethylenimine (PEI), poly(acrylic acid) (PAA), and montmorrilonite (MMT) clay are deposited via layer-by-layer (LbL) assembly. A five "quadlayer" (122 nm) coating deposited on 51 μm polystyrene is shown to lower both hydrogen and helium permeability three orders of magnitude against bare polystyrene, demonstrating better performance than thick-laminated ethylene vinyl-alcohol (EVOH) copolymer film and even metallized polyolefin/polyester film. These excellent barrier properties are attributed to a "nanobrick wall" structure. This highly flexible coating represents the first demonstration of an LbL deposited film with low hydrogen and helium permeability and is an ideal candidate for several packaging and protection applications. PMID:25429915

  17. Plasma-polymerized carbon disulfide thin-film rechargeable batteries

    SciTech Connect

    Sadhir, R.K.; Schoch, K.F. Jr.

    1996-06-01

    This paper discusses the results on deposition conditions, rates of polymerization, and properties of carbon disulfide films prepared by two techniques, viz., plasma polymerization and argon-plasma-assisted polymerization of carbon disulfide. A higher rate of polymerization and sulfur content was obtained for carbon disulfide films prepared by the plasma-polymerization technique. A Li/LiClO{sub 4} propylene carbonate/PPCS cell was assembled using lithium foil, 2 M LiClO{sub 4}/PC electrolyte with polyolefin separator, and PPCS deposited on Pt foil. The electrode area was 1.3 cm{sup 2}. The cell cycled reversibly between 1 and 3 V and retained its capacity (5 mA h/g) well over 12 cycles. 14 refs., 11 figs., 5 tabs.

  18. Polyolefin-Based Aerogels

    NASA Technical Reports Server (NTRS)

    Lee, Je Kyun; Gould, George

    2012-01-01

    An organic polybutadiene (PB) rubberbased aerogel insulation material was developed that will provide superior thermal insulation and inherent radiation protection, exhibiting the flexibility, resiliency, toughness, and durability typical of the parent polymer, yet with the low density and superior insulation properties associated with the aerogels. The rubbery behaviors of the PB rubber-based aerogels are able to overcome the weak and brittle nature of conventional inorganic and organic aerogel insulation materials. Additionally, with higher content of hydrogen in their structure, the PB rubber aerogels will also provide inherently better radiation protection than those of inorganic and carbon aerogels. Since PB rubber aerogels also exhibit good hydrophobicity due to their hydrocarbon molecular structure, they will provide better performance reliability and durability as well as simpler, more economic, and environmentally friendly production over the conventional silica or other inorganic-based aerogels, which require chemical treatment to make them hydrophobic. Inorganic aerogels such as silica aerogels demonstrate many unusual and useful properties. There are several strategies to overcoming the drawbacks associated with the weakness and brittleness of silica aerogels. Development of the flexible fiber-reinforced silica aerogel composite blanket has proven one promising approach, providing a conveniently fielded form factor that is relatively robust toward handling in industrial environments compared to silica aerogel monoliths. However, the flexible silica aerogel composites still have a brittle, dusty character that may be undesirable, or even intolerable, in certain applications. Although the cross-linked organic aerogels such as resorcinol-formaldehyde (RF), polyisocyanurate, and cellulose aerogels show very high impact strength, they are also very brittle with little elongation (i.e., less rubbery). Also, silica and carbon aerogels are less efficient radiation shielding materials due to their lower content of hydrogen element. The present invention relates to maleinized polybutadiene (or polybutadiene adducted with maleic anhydride)- based aerogel monoliths and composites, and the methods for preparation. Hereafter, they are collectively referred to as polybutadiene aerogels. Specifically, the polybutadiene aerogels of the present invention are prepared by mixing a maleinized polybutadiene resin, a hardener containing a maleic anhydride reactive group, and a catalyst in a suitable solvent, and maintaining the mixture in a quiescent state for a sufficient period of time to form a polymeric gel. After aging at elevated temperatures for a period of time to provide uniformly stronger wet gels, the micro porous maleinized polybutadiene- based aerogel is then obtained by removing interstitial solvent by supercritical drying. The mesoporous maleinized polybutadiene-based aerogels contain an open-pore structure, which provides inherently hydrophobic, flexible, nearly unbreakable, less dusty aerogels with excellent thermal and physical properties. The materials can be used as thermal and acoustic insulation, radiation shielding, and vibration-damping materials. The organic PB-based rubber aerogels are very flexible, no-dust, and hydrophobic organics that demonstrated the following ranges of typical properties: densities of 0.08 to 0.255 grams per cubic centimeters, shrinkage factor (raerogel/rtarget) = 1.2 to 2.84, and thermal conductivity values of 20.0 to 35.0 mW/m-K.

  19. Reactions of atomic oxygen /O(3P)/ with polymer films

    NASA Technical Reports Server (NTRS)

    Golub, Morton A.

    1992-01-01

    The reactions of polymer films with oxygen atoms are reviewed focusing on laboratory tests on polybutadienes with different amount of 1,4 or 1,2 double bonds and their polyalkenamer homologues, polyimide (Kapton), and a series of polyolefines with increasing fluorine content. It is found that etch rates increase with decrease in -CH=CH- unsaturation, starting with 1,4 -polybutadiene and reaching the maximum rate with polyethylene or ethylene-propylene rubber. IN polybutadienes with both 1,4 and 1,2 double bonds, the rate of O(3P)-induced etching is lower the higher the 1,2 content. The reactions are confined to the polymer surface.

  20. Long-term Stability of Esomeprazole in 5% Dextrose Infusion Polyolefin Bags at 5 degrees C +/- 3 degrees C after Microwave Freeze-thaw Treatment.

    PubMed

    Hecq, Jean-daniel; Rolin, Catherine; Godet, Marie; Gillet, Patricia; Jamart, Jacques; Galanti, Laurence M

    2015-01-01

    To improve quality assurance, security, time management, and cost saving of drug delivery, preparation in advance of intravenous solutions has been developed for several infusion solutions. The objective of this study was to investigate the stability of esomeprazole 0.4 mg/mL and 0.8 mg/mL in 5% dextrose polyolefin bags after freezing, long-term storage, and microwave thawing. The stability of five polyolefin bags containing approximately 0.4 mg/mL of esomeprazole and five other bags containing approximately 0.8 mg/mL in 5% dextrose prepared under aseptic conditions was studied after freezing for 1 month at -20 degrees C, thawing in a microwave oven with a validated cycle, and stored at 5 degrees C +/- 3 degrees C. Esomeprazole concentration was measured by high-pressure liquid chromatography using a reversed-phase column C8, a mobile phase consisting of 35% of acetonitrile and 65% of Na2HPO4 buffer at pH 7.59 with HPO4 (2 M) and NaOH (0.5 M), and detection with a diode array detector at 280 nm. Visual, microscopic, and spectrophotometric observation and pH measurements were also performed. No precipitation occurred in the preparations but little change of color was observed. No microaggregate was observed with optical microscopy or revealed by a change of absorbance at 350, 410, and 550 nm. Based on a shelf life of 90% residual potency, esomeprazole solutions (0.4 and 0.8 mg/mL) were stable for at least 20 or 29 days, respectively, after a freezing and microwave thawing period, where 95% one-side lower confidence limit of the concentration-time profile remained superior to 90% of the initial concentration. During this period, the pH values of drug solutions have been observed to decrease without affecting chromatographic parameters. Within these limits, esomeprazole (0.4 and 0.8 mg/mL) in 5% dextrose infusions may be prepared and frozen in advance by a centralized intravenous admixture service, thawed, and stored at least 20 days at 5 degrees C +/- 3 degrees C

  1. In Digital Age, Sunshine Laws Turn Hazy

    ERIC Educational Resources Information Center

    Fleming, Nora

    2013-01-01

    School board members are struggling to interpret laws that govern where and how they do business now that as many conversations take place digitally as they do face to face. As online and digital interactions increase, so too does public concern that officials have more opportunities to violate state open-meetings and open-records laws meant to…

  2. Hazy and Dusty Skies over Western Africa

    NASA Technical Reports Server (NTRS)

    2004-01-01

    A pall of smoke and dust largely obscured the nations of Cote d'Ivoire, Ghana, Burkina Faso and southern Mali on January 12, 2004. The poor air quality in the region was a combined result of the hundreds of agricultural fires that were burning throughout western Africa during December and early January, and was likely to have been influenced by a Saharan dust storm that occurred several days earlier. These image data products from the Multi-angle Imaging SpectroRadiometer (MISR) illustrate the abundance of atmospheric particulate matter across the region.

    The left-hand panels are natural-color views from MISR's downward-pointing (nadir) and most obliquely forward-pointing cameras. At the nadir view, the shoreline of the Cote d'Ivoire and many other surface features are apparent, and the haze across the region is noticeable. The distinctive area of dark green vegetation (apparent below and left of image center) is situated in the Cote d'Ivoire, near the border with Ghana, to the east of the Komoe River and southwest of the Comoe National Park. At the oblique view the aerosol appears so thick that the coastline is completely obscured, but this region of dark vegetation and hilly terrain can still be discerned.

    The right-hand panel is generated through automated processing of data from multiple MISR cameras, and utilizes the change in scene brightness and contrast at different view angles to retrieve aerosol amounts, expressed as optical depth. The aerosol map indicates an optically thick atmosphere by the orange or yellow pixels, and clearer skies are indicated by blue pixels. Places where clouds or other factors precluded an aerosol retrieval are shown in dark gray. Aerosol properties are retrieved at a coarse spatial resolution of 17.6 kilometers.

    The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously and every 9 days views the entire globe between 82 degrees north and 82 degrees south latitude. These data products were generated from a portion of the imagery acquired during Terra orbit 21641. The panels cover an area of about 380 kilometers x 1425 kilometers, and utilize data from blocks 80 to 90 within World Reference System-2 path 195.

  3. Microphase-Separated PE/PEO Thin Films Prepared by Plasma-Assisted Vapor Phase Deposition.

    PubMed

    Choukourov, Andrei; Gordeev, Ivan; Ponti, Jessica; Uboldi, Chiara; Melnichuk, Iurii; Vaidulych, Mykhailo; Kousal, Jaroslav; Nikitin, Daniil; Hanyková, Lenka; Krakovský, Ivan; Slavínská, Danka; Biederman, Hynek

    2016-03-01

    Immiscible polymer blends tend to undergo phase separation with the formation of nanoscale architecture which can be used in a variety of applications. Different wet-chemistry techniques already exist to fix the resultant polymeric structure in predictable manner. In this work, an all-dry and plasma-based strategy is proposed to fabricate thin films of microphase-separated polyolefin/polyether blends. This is achieved by directing (-CH2-)100 and (-CH2-CH2-O-)25 oligomer fluxes produced by vacuum thermal decomposition of poly(ethylene) and poly(ethylene oxide) onto silicon substrates through the zone of the glow discharge. The strategy enables mixing of thermodynamically incompatible macromolecules at the molecular level, whereas electron-impact-initiated radicals serve as cross-linkers to arrest the subsequent phase separation at the nanoscale. The mechanism of the phase separation as well as the morphology of the films is found to depend on the ratio between the oligomeric fluxes. For polyolefin-rich mixtures, polyether molecules self-organize by nucleation and growth into spherical domains with average height of 22 nm and average diameter of 170 nm. For equinumerous fluxes and for mixtures with the prevalence of polyethers, spinodal decomposition is detected that results in the formation of bicontinuous structures with the characteristic domain size and spacing ranging between 5 × 10(1) -7 × 10(1) nm and 3 × 10(2)-4 × 10(2) nm, respectively. The method is shown to produce films with tunable wettability and biologically nonfouling properties. PMID:26953817

  4. Film Reviews.

    ERIC Educational Resources Information Center

    Lance, Larry M.; Atwater, Lynn

    1987-01-01

    Reviews four Human Sexuality films and videos. These are: "Personal Decisions" (Planned Parenthood Federation of America, 1985); "The Touch Film" (Sterling Production, 1986); "Rethinking Rape" (Film Distribution Center, 1985); "Not A Love Story" (National Film Board of Canada, 1981). (AEM)

  5. Radiation-induced grafting of acrylic acid onto polypropylene film and its biodegradability

    NASA Astrophysics Data System (ADS)

    Mandal, Dev K.; Bhunia, Haripada; Bajpai, Pramod K.; Chaudhari, C. V.; Dubey, K. A.; Varshney, L.

    2016-06-01

    Polypropylene based commodity polyolefins are widely used in packaging, manufacturing, electrical, pharmaceutical and other applications. The aim of the present work is to study the effect of grafting of acrylic acid on the biodegradability of acrylic acid grafted polypropylene. The effect of different conditions showed that grafting percentage increased with increase in monomer concentration, radiation dose and inhibitor concentration but decreased with increase in radiation dose rate. The maximum grafting of 159.4% could be achieved at optimum conditions. The structure of grafted polypropylene films at different degree of grafting was characterized by EDS, FTIR, TGA, DSC, SEM and XRD. EDS studies showed that the increase in acrylic acid grafting percentage increased the hydrophilicity of the grafted films. FTIR studies indicated the presence of acrylic acid on the surface of polypropylene film. TGA studies revealed that thermal stability decreased with increase in grafting percentage. DSC studies showed that melting temperature and crystallinity of the grafted polypropylene films lower than polypropylene film. SEM studies indicated that increase in acrylic acid grafting percentage increased the wrinkles in the grafted films. The maximum biodegradability could be achieved to 6.85% for 90.5% grafting. This suggested that microorganisms present in the compost could biodegrade acrylic acid grafted polypropylene.

  6. Properties and Performance Attributes of Novel Co-extruded Polyolefin Battery Separator Materials. Part 2; Electrical Properties

    NASA Technical Reports Server (NTRS)

    Baldwin, Richard S.

    2013-01-01

    As NASA prepares for its next era of manned spaceflight missions, advanced energy storage technologies are being developed and evaluated to address and enhance future mission needs and technical requirements. Cell-level components for advanced lithium-ion batteries possessing higher energy, more reliable performance and enhanced, inherent safety characteristics have been under development within the NASA infrastructure. A key component for safe and reliable cell performance is the cell separator, which separates the two energetic electrodes and functions to inhibit the occurrence of an internal short circuit but preserves an ionic current. Recently, a new generation of co-extruded separator films has been developed by ExxonMobil Chemical and introduced into their battery separator product portfolio. Several grades of this new separator material were evaluated with respect to dynamic mechanical properties and safety-related performance attributes, and the results of these evaluations were previously reported in "Part 1: Mechanical Properties" of this publication. This current paper presents safety-related performance results for these novel materials obtained by employing a complementary experimental methodology, which involved the analysis of separator impedance characteristics as a function of temperature. The experimental results from this study are discussed with respect to potential cell safety enhancement for future aerospace as well as for terrestrial energy storage needs, and they are compared with pertinent mechanical properties of these materials, as well as with current state-of-the practice separator materials.

  7. Properties and Performance Attributes of Novel Co-Extruded Polyolefin Battery Separator Materials. Part 1; Mechanical Properties

    NASA Technical Reports Server (NTRS)

    Baldwin, Richard S.; Guzik, Monica; Skierski, Michael

    2011-01-01

    As NASA prepares for its next era of manned spaceflight missions, advanced energy storage technologies are being developed and evaluated to address future mission needs and technical requirements and to provide new mission-enabling technologies. Cell-level components for advanced lithium-ion batteries possessing higher energy, more reliable performance and enhanced, inherent safety characteristics are actively under development within the NASA infrastructure. A key component for safe and reliable cell performance is the cell separator, which separates the two energetic electrodes and functions to prevent the occurrence of an internal short-circuit while enabling ionic transport. Recently, a new generation of co-extruded separator films has been developed by ExxonMobil Chemical and introduced into their battery separator product portfolio. Several grades of this new separator material have been evaluated with respect to dynamic mechanical properties and safety-related performance attributes. This paper presents the results of these evaluations in comparison to a current state-ofthe-practice separator material. The results are discussed with respect to potential opportunities to enhance the inherent safety characteristics and reliability of future, advanced lithium-ion cell chemistries.

  8. Evaluation of heat shrinkable films for shelf life, and quality of individually wrapped Royal Delicious apples under ambient conditions.

    PubMed

    Sharma, R R; Pal, R K; Singh, D; Samuel, D V K; Sethi, S; Kumar, A

    2013-06-01

    Effect of heat shrinkable films on shelf life and quality of apples under ambient conditions was studied. Fully mature Royal Delicious apples (starch index 2.5 on 4.0 point scale) were either shrink-wrapped in 3 heat shrinkable films like Cryovac (9 μ), polyolefin (13 μ) and LDPE (25 μ) or were not wrapped at all (control) and then stored at ambient conditions (22-28°C and 52-68% RH). Observations on physiological loss in weight (PLW), decay loss, firmness, juice recovery, total soluble solids (TSS), acidity, ascorbic acid content and overall sensory quality were recorded immediately before packing, and after packing at weekly intervals. Best results were obtained with Cryovac (9 μ) films, which exhibited least PLW (2.3%) and decay loss (2.8%) and higher juice recovery (65.2%) and TSS (16.4%) over other films or control. Apples wrapped in Cryovac films also had higher overall sensory acceptability (8.3 out of 9) over other films or control. These studies indicated that apples could be very well packed in Cryovac heat shrinkable films for about 35 days with least PLW or decay loss, and without any adverse effect on fruit quality. PMID:24425958

  9. Adaptive wettability-enhanced surfaces ordered on molded etched substrates using shrink film

    NASA Astrophysics Data System (ADS)

    Jayadev, Shreshta; Pegan, Jonathan; Dyer, David; McLane, Jolie; Lim, Jessica; Khine, Michelle

    2013-01-01

    Superhydrophobic surfaces in nature exhibit desirable properties including self-cleaning, bacterial resistance, and flight efficiency. However, creating such intricate multi-scale features with conventional fabrication approaches is difficult, expensive, and not scalable. By patterning photoresist on pre-stressed shrink-wrap film, which contracts by 95% in surface area when heated, such features over large areas can be obtained easily. Photoresist serves as a dry etch mask to create complex and high-aspect ratio microstructures in the film. Using a double-shrink process, we introduce adaptive wettability-enhanced surfaces ordered on molded etched (AWESOME) substrates. We first create a mask out of the children’s toy ‘Shrinky-Dinks’ by printing dots using a laserjet printer. Heating this thermoplastic sheet causes the printed dots to shrink to a fraction of their original size. We then lithographically transfer the inverse pattern onto photoresist-coated shrink-wrap polyolefin film. The film is then plasma etched. After shrinking, the film serves as a high-aspect ratio mold for polydimethylsiloxane, creating a superhydrophobic surface with water contact angles >150° and sliding angles <10°. We pattern a microarray of ‘sticky’ spots with a dramatically different sliding angle compared to that of the superhydrophobic region, enabling microtiter-plate type assays without the need for a well plate.

  10. Quality changes of 'Sanguinello' oranges wrapped with different plastic films under simulated marketing conditions.

    PubMed

    D'Aquino, S; Malinconico, M; Avella, M; Di Lorenzo, M L; Mura; Palma, A

    2013-01-01

    Chemical and eating quality of citrus fruit changes slowly after harvest, and quality alteration is mainly due to shrinkage, loss of firmness, excessive weight loss and decay rather than a reduction of nutritional value and taste features. Film wrapping may be a suitable means to reduce transpiration and preserve market quality provided film permeability to gases does not lead to: 1) a reduction of in-package O2 partial pressure at a point that would induce anaerobic respiration; 2) an increase of CO2 concentration to toxic levels. This experiment was carried out to study quality changes of 'Sanguinello' oranges treated or not treated with 500 mg/L imazalil (IMZ) and wrapped with continuous, macro- or micro-perforated polyolefinic films. Wrapped and no-wrapped fruit were stored at 20 degrees C and 60% RH for 20 or 30 days. In-package gas composition of the macro-perforated film showed no significant difference compared to air composition, while in-package partial pressure of CO2 and O2 ranged between 4 (continuous film) and 9.8 kPa (micro-perforated films), and 14.8 (continuous film) and 5 kPa (micro-perforated films), respectively. After 30 days of storage weight loss in fruit wrapped with the macro-perforated film was (4.3%) slightly lowerthan un-packed fruit (5%), while in all other packages weight loss never exceeded 0.7%.Quality changes were quite stable over storage in all treatments, although slight but significantly lower levels of total soluble solids and ascorbic acid were detected in micro-perforated films with the lowest degree of perforation. However, the sensory analysis denoted a remarkable decrease of firmness in un-wrapped or wrapped fruit with macro-perforated film, while a moderate build-up of off-flavour, which reduced the eating quality, developed in micro-perforated films. Decay ranged between 6 and 12% in not treated fruit, with the lowest incidence detected in un-wrapped fruit, whereas differences among the different films were not

  11. Tunable nano bead arrays on film for controlling propogation of light

    NASA Astrophysics Data System (ADS)

    Sharac, Nicholas; Sharma, Himanshu; Khine, Michelle; Ragan, Regina

    2013-09-01

    Periodic arrays of sub-wavelength structures have garnered significant interest for surface enhanced Raman spectroscopy (SERS) and metal enhanced fluorescence (MEF), and for anti-reflective coating properties. For SERS and MEF, coupling metal nanoparticles with nanometer scale spacing can induce strong local electromagnetic field enhancements at the plasmon resonance, significantly increasing the Raman signal or fluorescence of a molecule. Inspired by moth eyes, metal nanoparticle arrays can reduce the reflection of incident light, shown useful for improving the efficiency of solar cells. Here, we present fabrication of robust, tunable, inexpensive and quickly reproducible gold coated, nanopillar arrays for applications in enhancing Raman/fluorescence signals or antireflective surfaces for efficient solar cells. To create homogenous metallic nanostructures with controllable sizes and interparticle spacings, we have integrated conventional nanosphere lithography techniques with thermally responsive polyolefin (PO) films. Spin coating 500 nm PS beads onto PO substrates, followed by oxygen plasma etching, is used to vary the size and periodicity of the resulting PS nanopillar bead array. A 50 nm thick gold film can then be added using chemical vapor deposition (CVD). Nanostructures were characterized with scanning electron microscopy and atomic force microscopy. When heated from room temperature up to 115oC, structures on PO films undergo a reduction in feature size and interparticle spacing by up to 35 % in length and 50% in surface area.

  12. Film Reviews

    ERIC Educational Resources Information Center

    Dowling, John, Ed.

    1976-01-01

    Reviews five instructional films on: P-N junctions; crystal diodes; nuclear fusion research; Schlieren photography; and the energy crisis; including discussions of solar, nuclear, and fossil fuel energy. Also lists numerous other available films. (MLH)

  13. Film Boxes.

    ERIC Educational Resources Information Center

    Osterer, Irv

    2002-01-01

    Presents an art lesson in which students created three-dimensional designs for 35mm film packages to improve graphic arts learning. Describes how the students examined and created film boxes using QuarkXPress software. (CMK)

  14. Nanocomposite films

    DOEpatents

    Mitlin, David; , Ophus, Colin; Evoy, Stephane; Radmilovic, Velimir; Mohammadi, Reza; Westra, Ken; Nelson-Fitzpatrick, Nathaniel; Lee, Zonghoon

    2010-07-20

    A thin-film composition of nanocrystal molybdenum in an amorphous metallic matrix may be formed by co-sputtering Mo with aluminum or nickel. NEMS cantilevers may be formed from the film. The films exhibit high nanoindentation hardness and a reduction in roughness and intrinsic stress, while maintaining resistivity in the metallic range.

  15. On Film

    ERIC Educational Resources Information Center

    Watts, Marty

    2006-01-01

    In this article, the author discusses the role of window films in enhancing indoor air quality in schools. Historically, window film has been used to reduce temperatures in buildings prone to overheating. Too much solar energy entering through windows makes occupants uncomfortable and air conditioning more costly. Film has been a simple solution…

  16. Humanistic Films.

    ERIC Educational Resources Information Center

    Gaffney, Maureen, Ed.

    1981-01-01

    Designed for media specialists and educators, this issue includes seven articles focusing on humanistic films for children. Following a brief editorial encouraging the ideals of humanism, the first article presents an analysis of seven films with positive sex-role models. Included is a model for evaluating children's films. The second article…

  17. Radiation-hardened polymeric films

    DOEpatents

    Arnold, Jr., Charles; Hughes, Robert C.; Kepler, R. Glen; Kurtz, Steven R.

    1986-01-01

    The radiation-induced conductivity of polymeric dielectrics with low electronic mobility is reduced by doping with electron donor or electron acceptor compounds at a level of 10.sup.15 to 10.sup.21 molecules of dopant/cm.sup.3. Polyesters, polyolefins, perfluoropolyolefins, vinyl polymers, vinylidene polymers, polycarbonates, polysulfones and polyimides can benefit from such a treatment. Usable dopants include 2,4,7-trinitro-9-fluorenone, tetracyanethylene, 7,7,8,8-tetracyanoquinodimethane, m-dinitrobenzene, 2-isopropylcarbazole, and triphenylamine.

  18. Radiation-hardened polymeric films

    DOEpatents

    Arnold, C. Jr.; Hughes, R.C.; Kepler, R.G.; Kurtz, S.R.

    1984-07-16

    The radiation-induced conductivity of polymeric dielectrics with low electronic mobility is reduced by doping with electron donor or electron acceptor compounds at a level of 10/sup 15/ to 10/sup 21/ molecules of dopant/cm/sup 3/. Polyesters, polyolefins, perfluoropolyolefins, vinyl polymers, vinylidene polymers, polycarbonates, polysulfones and polyimides can benefit from such a treatment. Usable dopants include 2,4,7-trinitro-9-fluorenone, tetracyanethylene, 7,7,8,8-tetracyanoquinodimethane, m-dinitrobenzene, 2-isopropylcarbazole, and triphenylamine.

  19. Film ispalators

    SciTech Connect

    Startsev, Aleksandr V; Stoilov, Yurii Yu

    2002-05-31

    New physical objects, ispalators based on free soap films, exhibit persistent flows of the soap solution in open and closed volumes in air with additions of gases of the C{sub 8}F{sub 18} type (p = 20 Torr) at temperature drops on the films of the order of tenths and hundredths of kelvin. The flows move continuously at a velocity of 5 - 20 cm s{sup -1}. It is found that the parts of an inclined ispalator film show anomalous behaviour upon heating: their weight increases and they move downward over the film, whereas the unheated parts of the film move upward. Continuous radial vortex flows accompanied by the formation and washing of the regions of a thin black film are observed on circular films in closed volumes upon their uniform external cooling by evaporating water for 5 - 10 hours. The rapid flows make film ispalators the efficient heat carriers, which operate at small temperature drops (tenths and hundredths of kelvin) and surpass copper in the amount of thermal energy being transferred. The outlook for the further study and applications of film ispalators for detecting thermal fields and laser radiation is discussed. (laser applications and other topics in quantum electronics)

  20. Thin Film?

    NASA Astrophysics Data System (ADS)

    Kariper, İ. Afşin

    2014-09-01

    This study focuses on the critical surface tension of lead sulfite (PbSO3) crystalline thin film produced with chemical bath deposition on substrates (commercial glass).The PbSO3 thin films were deposited at room temperature at different deposition times. The structural properties of the films were defined and examined according to X-ray diffraction (XRD) and the XRD results such as dislocation density, average grain size, and no. of crystallites per unit area. Atomic force microscopy was used to measure the film thickness and the surface properties. The critical surface tension of the PbSO3 thin films was measured with an optical tensiometer instrument and calculated using the Zisman method. The results indicated that the critical surface tension of films changed in accordance with the average grain size and film thickness. The film thickness increased with deposition time and was inversely correlated with surface tension. The average grain size increased according to deposition time and was inversely correlated with surface tension.

  1. About Films.

    ERIC Educational Resources Information Center

    Christman, Robert; Krockover, Gerald H.

    1984-01-01

    Lists and briefly describes 46 college-level films. Films are arranged in the following categories: volcanism and earthquakes; plate tectonics; energy, water, and environmental concerns; petroleum and coal; astronomy; space exploration, space shuttle; paleontology; geomorphology; and mineralogy, petrology, and economic geology. (BC)

  2. Thin Films

    NASA Astrophysics Data System (ADS)

    Khorshidi, Zahra; Bahari, Ali; Gholipur, Reza

    2014-11-01

    Effect of annealing temperature on the characteristics of sol-gel-driven Ta ax La(1- a) x O y thin film spin-coated on Si substrate as a high- k gate dielectric was studied. Ta ax La(1- a) x O y thin films with different amounts of a were prepared (as-prepared samples). X-ray diffraction measurements of the as-prepared samples indicated that Ta0.3 x La0.7 x Oy film had an amorphous structure. Therefore, Ta0.3 x La0.7 x O y film was chosen to continue the present studies. The morphology of Ta0.3 x La0.7 x O y films was studied using scanning electron microscopy and atomic force microscopy techniques. The obtained results showed that the size of grain boundaries on Ta0.3 x La0.7 x O y film surfaces was increased with increasing annealing temperature. Electrical and optical characterizations of the as-prepared and annealed films were investigated as a function of annealing temperature using capacitance-voltage ( C- V) and current density-voltage ( J- V) measurements and the Tauc method. The obtained results demonstrated that Ta0.3 x La0.7 x O y films had high dielectric constant (≈27), wide band gap (≈4.5 eV), and low leakage current density (≈10-6 A/cm2 at 1 V).

  3. Film Language.

    ERIC Educational Resources Information Center

    Hudlin, Edward W.

    1979-01-01

    The author briefly surveys some of the claims made about the presumed nature of film as language and some of the problems that arise. He considers the views of two influential schools of film criticism: the Russian formalists (Pudovkin and Eisenstein) and the British semiologist (Peter Wollen). (Author/SJL)

  4. Migration of selected hydrocarbon contaminants into dry semolina and egg pasta packed in direct contact with virgin paperboard and polypropylene film.

    PubMed

    Barp, Laura; Suman, Michele; Lambertini, Francesca; Moret, Sabrina

    2015-01-01

    Migration of mineral oil saturated hydrocarbons (MOSH), polyolefin oligomeric saturated hydrocarbons (POSH), and polyalphaolefins (PAO from hot melts) into dry semolina and egg pasta packed in direct contact with virgin paperboard or polypropylene (PP) flexible film was studied. Migration was monitored during shelf life (up to 24 months), through storage in a real supermarket (packs kept on shelves), conditions preventing exchange with the surrounding environment (packs wrapped in aluminium foil), and storage in a warehouse (packs inside of the transport box of corrugated board). Semolina pasta packed in virgin paperboard (without hot melts) had a MOSH content lower than 1.0 mg kg(-1). An increasing contamination with PAO belonging to the adhesives used to close the boxes was detected in egg pasta, wrapped in aluminium (1.5 and 5 mg kg(-1) after 3 and 24 months, respectively). An environmental contribution to total hydrocarbon contamination was observed in egg pasta kept on shelves that, after 3 and 24 months, showed levels of PAO/MOSH < C25 around 3 and 10 mg kg(-1), respectively. The migration of POSH from PP film into egg pasta wrapped in aluminium was around 0.6 mg kg(-1) after 3 months of contact and reached 1.7 mg kg(-1) after 24 months of contact. After 9 months of contact, semolina pasta packed in PP film and stored in the transport box showed that some MOSH migrated into the pasta from the board of the transport box (through the plastic film). PMID:26209063

  5. Film Makers On Film Making.

    ERIC Educational Resources Information Center

    Geduld, Harry M., Ed.

    This collection includes essays by and interviews with more than 30 film-makers, both classic and contemporary, on the subjects of their major interests and procedures in making films. The directors are: Louis Lumiere, Cecil Hepworth, Edwin S. Porter, Mack Sennett, David W. Griffith, Robert Flaherty, Charles Chaplin, Eric von Stroheim, Dziga…

  6. Degradation of ZnO-Based Window Layers for Thin-Film CIGS by Accelerated Stress Exposures

    SciTech Connect

    Pern, F. J.; Noufi, R.; To, B.; DeHart, C.; Li, X.; Glick, S. H.

    2008-01-01

    The reliability of ZnO-based window layer for CuInGaSe{sub 2} (CIGS) solar cells was investigated. Samples of RF magnetron-sputtered, single-layer intrinsic and Al-doped ZnO and their combined bilayer on glass substrates were exposed in a weatherometer (WOM) and damp heat (DH) conditions with or without acetic acid vapor. Some preliminary samples of single-layer Al-doped Zn{sub 1-x}Mg{sub x}O (ZMO) alloy, a potential replacement for Al:ZnO with a wider bandgap, were also evaluated in the DH. The Al-doped ZnO and ZMO films showed irreversible loss in the conducting properties, free carrier mobility, and characteristic absorption band feature after <500-h DH exposure, with the originally clear transparent films turned into white hazy insulating films and the degradation rate follows the trend of (DH + acetic acid) > DH > WOM. The degradation rate was also reduced by higher film thickness, higher deposition substrate temperature, and dry-out intervals. The results of X-ray diffraction analysis indicate that the ZnO-based films underwent structural degeneration by losing their highly (002) preferential orientation with possible transformation from hexagonal into cubic and formation of Zn(OH){sub 2}. Periodic optical micro-imaging observations suggested a temporal process that involves initial hydrolysis of the oxides at sporadic weak spots, swelling and popping of the hydrolyzed spots due to volume increase, segregation of hydrolyzed regions causing discontinuity of electrical path, hydrolysis of the oxide-glass interface, and finally, formation of insulating oxides/hydroxides with visible delamination over larger areas.

  7. Film Reviews

    ERIC Educational Resources Information Center

    Ladd, George T.

    1974-01-01

    Briefly describes films about the following topics: water cycles, the energy crisis, the eruption of Mt. Aetna, the hot springs of Yellowstone National Park, and methods of using pine cones to determine the ages of ancient civilizations. (MLH)

  8. Piezoelectric Film.

    ERIC Educational Resources Information Center

    Garrison, Steve

    1992-01-01

    Presents activities that utilize piezoelectric film to familiarize students with fundamental principles of electricity. Describes classroom projects involving chemical sensors, microbalances, microphones, switches, infrared sensors, and power generation. (MDH)

  9. Polymer films

    DOEpatents

    Granick, Steve; Sukhishvili, Svetlana A.

    2004-05-25

    A film contains a first polymer having a plurality of hydrogen bond donating moieties, and a second polymer having a plurality of hydrogen bond accepting moieties. The second polymer is hydrogen bonded to the first polymer.

  10. Polymer films

    DOEpatents

    Granick, Steve; Sukhishvili, Svetlana A.

    2008-12-30

    A film contains a first polymer having a plurality of hydrogen bond donating moieties, and a second polymer having a plurality of hydrogen bond accepting moieties. The second polymer is hydrogen bonded to the first polymer.

  11. Atmospheric production of glycolaldehyde under hazy prebiotic conditions.

    PubMed

    Harman, Chester E; Kasting, James F; Wolf, Eric T

    2013-04-01

    The early Earth's atmosphere, with extremely low levels of molecular oxygen and an appreciable abiotic flux of methane, could have been a source of organic compounds necessary for prebiotic chemistry. Here, we investigate the formation of a key RNA precursor, glycolaldehyde (2-hydroxyacetaldehyde, or GA) using a 1-dimensional photochemical model. Maximum atmospheric production of GA occurs when the CH4:CO2 ratio is close to 0.02. The total atmospheric production rate of GA remains small, only 1 × 10(7) mol yr(-1). Somewhat greater amounts of GA production, up to 2 × 10(8) mol yr(-1), could have been provided by the formose reaction or by direct delivery from space. Even with these additional production mechanisms, open ocean GA concentrations would have remained at or below ~1 μM, much smaller than the 1-2 M concentrations required for prebiotic synthesis routes like those proposed by Powner et al. (Nature 459:239-242, 2009). Additional production or concentration mechanisms for GA, or alternative formation mechanisms for RNA, are needed, if this was indeed how life originated on the early Earth. PMID:23695543

  12. A revised, hazy methane greenhouse for the Archean Earth.

    PubMed

    Haqq-Misra, Jacob D; Domagal-Goldman, Shawn D; Kasting, Patrick J; Kasting, James F

    2008-12-01

    Geological and biological evidence suggests that Earth was warm during most of its early history, despite the fainter young Sun. Upper bounds on the atmospheric CO2 concentration in the Late Archean/Paleoproterozoic (2.8-2.2 Ga) from paleosol data suggest that additional greenhouse gases must have been present. Methanogenic bacteria, which were arguably extant at that time, may have contributed to a high concentration of atmospheric CH4, and previous calculations had indicated that a CH4-CO2-H2O greenhouse could have produced warm Late Archean surface temperatures while still satisfying the paleosol constraints on pCO2. Here, we revisit this conclusion. Correction of an error in the CH4 absorption coefficients, combined with the predicted early onset of climatically cooling organic haze, suggest that the amount of greenhouse warming by CH4 was more limited and that pCO2 must therefore have been 0.03 bar, at or above the upper bound of the value obtained from paleosols. Enough warming from CH4 remained in the Archean, however, to explain why Earth's climate cooled and became glacial when atmospheric O2 levels rose in the Paleoproterozoic. Our new model also shows that greenhouse warming by higher hydrocarbon gases, especially ethane (C2H6), may have helped to keep the Late Archean Earth warm. PMID:19093801

  13. Thin Films

    NASA Astrophysics Data System (ADS)

    Naffouti, Wafa; Nasr, Tarek Ben; Mehdi, Ahmed; Kamoun-Turki, Najoua

    2014-11-01

    Titanium dioxide (TiO2) thin films were synthesized on glass substrates by spray pyrolysis. The effect of solution flow rate on the physical properties of the films was investigated by use of x-ray diffraction (XRD), scanning electron microscopy, atomic force microscopy (AFM), and spectrophotometry techniques. XRD analysis revealed the tetragonal anatase phase of TiO2 with highly preferred (101) orientation. AFM images showed that grain size on top of TiO2 thin films depended on solution flow rate. An indirect band gap energy of 3.46 eV was determined by means of transmission and reflection measurements. The envelope method, based on the optical transmission spectrum, was used to determine film thickness and optical constants, for example real and imaginary parts of the dielectric constant, refractive index, and extinction coefficient. Ultraviolet and visible photoluminescence emission peaks were observed at room temperature. These peaks were attributed to the intrinsic emission and to the surface defect states, respectively.

  14. Film Credits

    ERIC Educational Resources Information Center

    Borja, Rhea R.

    2006-01-01

    With the advent of easy-to-use digital technology, schools are responding to the interests of their media-savvy students by offering more courses in filmmaking. In this article, the author features different films produced by students. Among other things, she discusses the students' growing interest in filmmaking.

  15. Black Films and Film-Makers.

    ERIC Educational Resources Information Center

    Patterson, Lindsay, Ed.

    The development of black films and the attitudes of the film industry toward black films and black actors are some of the topics examined in this anthology of essays. Section 1, "Nigger to Supernigger," contains such articles as "The Death of Rastus: Negroes in American Films" by Thomas R. Cripps and "Folk Values in a New Medium" by Alain Locke…

  16. Nanoscale chemical and mechanical characterization of thin films:sum frequency generation (SFG) vibrational spectroscopy at buriedinterfaces

    SciTech Connect

    Kweskin, S.J.

    2006-05-19

    Sum frequency generation (SFG) surface vibrational spectroscopy was used to characterize interfaces pertinent to current surface engineering applications, such as thin film polymers and novel catalysts. An array of advanced surface science techniques like scanning probe microscopy (SPM), x-ray photoelectron spectroscopy (XPS), gas chromatography (GC) and electron microscopy were used to obtain experimental measurements complementary to SFG data elucidating polymer and catalyst surface composition, surface structure, and surface mechanical behavior. Experiments reported in this dissertation concentrate on three fundamental questions: (1) How does the interfacial molecular structure differ from that of the bulk in real world applications? (2) How do differences in chemical environment affect interface composition or conformation? (3) How do these changes correlate to properties such as mechanical or catalytic performance? The density, surface energy and bonding at a solid interface dramatically alter the polymer configuration, physics and mechanical properties such as surface glass transition, adhesion and hardness. The enhanced sensitivity of SFG at the buried interface is applied to three systems: a series of acrylates under compression, the compositions and segregation behavior of binary polymer polyolefin blends, and the changes in surface structure of a hydrogel as a function of hydration. In addition, a catalytically active thin film of polymer coated nanoparticles is investigated to evaluate the efficacy of SFG to provide in situ information for catalytic reactions involving small mass adsorption and/or product development. Through the use of SFG, in situ total internal reflection (TIR) was used to increase the sensitivity of SFG and provide the necessary specificity to investigate interfaces of thin polymer films and nanostructures previously considered unfeasible. The dynamic nature of thin film surfaces is examined and it is found that the non

  17. Film and History.

    ERIC Educational Resources Information Center

    Schaber, Robin L.

    2002-01-01

    Provides an annotated bibliography of Web sites that focus on using film to teach history. Includes Web sites in five areas: (1) film and education; (2) history of cinema; (3) film and history resources; (4) film and women; and (5) film organizations. (CMK)

  18. Film: An Introduction.

    ERIC Educational Resources Information Center

    Fell, John L.

    "Understanding Film," the opening section of this book, discusses perceptions of and responses to film and the way in which experiences with and knowledge of other media affect film viewing. The second section, "Film Elements," analyzes the basic elements of film: the use of space and time, the impact of editing, sound and color, and the effects…

  19. Ferroelectric ultrathin perovskite films

    DOEpatents

    Rappe, Andrew M; Kolpak, Alexie Michelle

    2013-12-10

    Disclosed herein are perovskite ferroelectric thin-film. Also disclosed are methods of controlling the properties of ferroelectric thin films. These films can be used in a variety materials and devices, such as catalysts and storage media, respectively.

  20. 21 CFR 178.3610 - α-Methylstyrene-vinyltoluene resins, hydrogenated.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... safely used as components of polyolefin film intended for use in contact with food, subject to the... polyolefin film is produced from olefin polymers complying with § 177.1520 of this chapter, and the average thickness of the film in the form in which it contacts food does not exceed 0.002 inch....

  1. Hydrocarbon compositions containing polyolefin graft polymers

    SciTech Connect

    Kapuscinski, M.M.; Liu, C.S.; Hart, W.P.; Grina, L.D.

    1987-02-03

    A graft polymer is described comprising an oil-soluble, substantially linear, carbon-carbon backbone polymer having graft polymerized thereon units derived from, as a functional monomer, the reaction product of (i) an unsaturated aldehyde or ketone and (ii) a primary or secondary amine which contains at least one nitrogen atom in a heterocyclic ring. The graft polymer is also described wherein the backbone polymer is a copolymer of ethylene-propylene or a terpolymer of ethylene-propylene-diene monomer.

  2. Crystallization in Ordered Polydisperse Polyolefin Diblock

    SciTech Connect

    Li, Sheng; Register, Richard A.; Landes, Brian G.; Hustad, Phillp D.; Weinhold, Jeffrey D.

    2010-08-27

    The morphologies of polydisperse ethylene-octene diblock copolymers, synthesized via a novel coordinative chain transfer polymerization process, are examined using two-dimensional synchrotron small-angle and wide-angle X-ray scattering on flow-aligned specimens. The diblock copolymers comprise one amorphous block with high 1-octene content and one semicrystalline block with relatively low 1-octene content, and each block ideally exhibits the most-probable distribution. Near-symmetric diblocks with a sufficiently large octene differential between the amorphous and semicrystalline blocks show well-ordered lamellar domain structures with long periods exceeding 100 nm. Orientation of these domain structures persists through multiple melting/recrystallization cycles, reflecting a robust structure which self-assembles in the melt. The domain spacings are nearly 3-fold larger than those in near-monodisperse polyethylene block copolymers of similar molecular weights. Although the well-ordered lamellar domain structure established in the melt is preserved in the solid state, the crystallites are isotropic in orientation. These materials display crystallization kinetics consistent with a spreading growth habit, indicating that the lamellae do not confine or template the growing crystals. The exceptionally large domain spacings and isotropic crystal growth are attributed to interblock mixing resulting from the large polydispersity; short hard blocks dissolved in the soft-block-rich domains swell the domain spacing in the melt and allow hard block crystallization to proceed across the lamellar domain interfaces.

  3. Crystallization in Ordered Polydisperse Polyolefin Diblock Copolymers

    SciTech Connect

    Li, Sheng; Register, Richard A.; Landes, Brian G.; Hustad, Phillip D.; Weinhold, Jeffrey D.

    2010-12-07

    The morphologies of polydisperse ethylene-octene diblock copolymers, synthesized via a novel coordinative chain transfer polymerization process, are examined using two-dimensional synchrotron small-angle and wide-angle X-ray scattering on flow-aligned specimens. The diblock copolymers comprise one amorphous block with high 1-octene content and one semicrystalline block with relatively low 1-octene content, and each block ideally exhibits the most-probable distribution. Near-symmetric diblocks with a sufficiently large octene differential between the amorphous and semicrystalline blocks show well-ordered lamellar domain structures with long periods exceeding 100 nm. Orientation of these domain structures persists through multiple melting/recrystallization cycles, reflecting a robust structure which self-assembles in the melt. The domain spacings are nearly 3-fold larger than those in near-monodisperse polyethylene block copolymers of similar molecular weights. Although the well-ordered lamellar domain structure established in the melt is preserved in the solid state, the crystallites are isotropic in orientation. These materials display crystallization kinetics consistent with a spreading growth habit, indicating that the lamellae do not confine or template the growing crystals. The exceptionally large domain spacings and isotropic crystal growth are attributed to interblock mixing resulting from the large polydispersity; short hard blocks dissolved in the soft-block-rich domains swell the domain spacing in the melt and allow hard block crystallization to proceed across the lamellar domain interfaces.

  4. Surface photodegradation of a polyolefin copolymer

    NASA Astrophysics Data System (ADS)

    Brandon, J. Ph.; Cabala, R.; Chambaudet, A.; Jaffiol, F.

    1988-05-01

    Methods and data concerning the morphological and microstructural characterizations of the surface of a polypropylene copolymer (PP-PE) are presented: samples of this polymer were moulded under different temperature conditions; some were subjected to UV irradiation in conditioning chambers such as the Xenotest apparatus. Scanning electron microscopy (SEM) gives pictures of a surface morphologies before and after irradiation and shows the emergence of microcracks resulting from polymer photodegradation. Methods such as mercury microporosimetry provide quantitative analyses of these cracks. Selective surface etching of samples reveals crystalline areas in the microstructure of the polymer. Infrared (attenuated total reflection) spectroscopy and X-ray diffraction permit determining the crystallinity ratios of the samples before and after degradation.

  5. Contemporary Films' Mini Course on Film Study.

    ERIC Educational Resources Information Center

    Schillaci, Peter

    This minicourse on film study can be a unit in English, in arts, or in the humanities. It can help to launch a film study course or complement an introduction to theater. Whatever form it takes, it helps to build a bridge to the student's media environment. Part one, the language of images, utilizes four films which demonstrate the basic elements…

  6. [Films: China and Japan].

    ERIC Educational Resources Information Center

    Gumport, Roberta H.

    The history of filmmaking in China and Japan and film usage in teaching are considered in this document. Pointing out how films describe historical context and culture, the document also describes various techniques of film making. Films in China were heavily influenced by western models and have tended to be tools of the power structure, as…

  7. Carbon thin film thermometry

    NASA Technical Reports Server (NTRS)

    Collier, R. S.; Sparks, L. L.; Strobridge, T. R.

    1973-01-01

    The work concerning carbon thin film thermometry is reported. Optimum film deposition parameters were sought on an empirical basis for maximum stability of the films. One hundred films were fabricated for use at the Marshall Space Flight Center; 10 of these films were given a precise quasi-continuous calibration of temperature vs. resistance with 22 intervals between 5 and 80 K using primary platinum and germanium thermometers. Sensitivity curves were established and the remaining 90 films were given a three point calibration and fitted to the established sensitivity curves. Hydrogen gas-liquid discrimination set points are given for each film.

  8. Hydrogen film cooling investigation

    NASA Technical Reports Server (NTRS)

    Rousar, D. C.; Ewen, R. L.

    1973-01-01

    Effects of flow turning, flow acceleration, and supersonic flow on film cooling were determined experimentally and correlated in terms of an entrainment film cooling model. Experiments were conducted using thin walled metal test sections, hot nitrogen mainstream gas, and ambient hydrogen or nitrogen as film coolants. The entrainment film cooling model relates film cooling effectiveness to the amount of mainstream gases entrained with the film coolant in a mixing layer. The experimental apparatus and the analytical model used are described in detail and correlations for the entrainment fraction and film coolant-to-wall heat transfer coefficient are presented.

  9. Educational Films and the Historian

    ERIC Educational Resources Information Center

    Youngs, J. William T., Jr.

    1975-01-01

    Suggestions on how historians might use educational films more efficiently in the classroom are given. The range and diversity of educational films, educational film bibliography and criticism, and the classroom uses of films are discussed. (JR)

  10. Thin film metrology.

    PubMed

    Nitsch, Gerald; Flinn, Gregory

    2007-10-01

    Thin film metrology is suitable for characterising and performing quality control of a variety of coatings and films used in medical applications. The capabilities of today's systems are described. PMID:18078184

  11. Film as Film; Understanding and Judging Movies.

    ERIC Educational Resources Information Center

    Perkins, V. F.

    The criteria for judging movies which are presented here are based on the belief that film criticism becomes rational, if not "objective", when it displays and inspects the nature of its evidence and the bases of its arguments. The author dissents from the view of early film theorists that montage is the essence of cinema, and that cinema is to be…

  12. Exploring the Film.

    ERIC Educational Resources Information Center

    Kuhns, William; Stanley, Robert

    The purpose of film study is defined here in the words of D. W. Griffiths: "My goal is above all to make you see." This book is intended to be used as a text in a film study course. It traces the development of films from a scientific curiosity through silent films to modern wide screen productions. A comic strip is used to demonstrate the effect…

  13. 99 Films on Drugs.

    ERIC Educational Resources Information Center

    Weber, David O., Ed.

    This catalog describes and evaluates 16-millimeter films about various aspects of drug use. Among the subjects covered by the 99 films are the composition and effects of different drugs, reasons why people use drugs, life in the drug culture, the problem of law enforcement, and various means of dealing with drug users. Each film is synopsized. Two…

  14. The Sponsored Film.

    ERIC Educational Resources Information Center

    Klein, Walter J.

    For public relations professionals and would-be sponsors of films, this book provides guidelines for understanding the film medium and its potential as a persuasive force in industry, government, organizations, and religious orders. For filmmakers, it brings together practical information needed to survive in the sponsored-film industry and to…

  15. Focus on Shakespearean Films.

    ERIC Educational Resources Information Center

    Eckert, Charles W., Ed.

    This is an anthology of reviews and critical pieces of the significant and available Shakespearean films made between 1935 and 1966. Included are three general essays on Shakespearean film by Ian Johnson, Henri Lemaitre, and Geoffrey Reeves. The specific films and their reviewers are: A Midsummer's Night Dream (1935) Allardyce Nicoll and Richard…

  16. Marine Science Film Catalogue.

    ERIC Educational Resources Information Center

    Chapman, Frank L.

    Forty-eight motion picture films and filmstrips in the field of marine science are catalogued in this booklet. Following the alphabetical index, one page is devoted to each film indicating its type, producer, recommended grade level, running time, and presence of color and/or sound. A summary of film content, possible uses, and outstanding…

  17. Thick Film Interference.

    ERIC Educational Resources Information Center

    Trefil, James

    1983-01-01

    Discusses why interference effects cannot be seen with a thick film, starting with a review of the origin of interference patterns in thin films. Considers properties of materials in films, properties of the light source, and the nature of light. (JN)

  18. TEACHING COMPOSITION WITH FILM.

    ERIC Educational Resources Information Center

    COURSEN, HERBERT R., JR.

    A COMPOSITION PROGRAM DESIGNED TO GIVE UPWARD BOUND STUDENTS A FEELING OF SUCCESS WAS BASED ON FILMS WHICH THE STUDENTS VIEWED, DISCUSSED, AND WROTE ABOUT. THE FILMS FELL ROUGHLY INTO THE CATEGORIES OF SOCIAL PROBLEMS, POLITICS AND PROPAGANDA, AND ART AND MUSIC. FOLLOWING CLASS DISCUSSIONS, STUDENTS WERE REQUIRED MERELY TO "WRITE ABOUT THE FILM."…

  19. Films for Special Education.

    ERIC Educational Resources Information Center

    Tringo, John L.

    Listed are approximately 500 films in the various areas of special education. The listing has been compiled from film company catalogs, social agency listings, and National Audiovisual Center listings. Information stated is that which was in the source materials (usually name, length, source, and brief description). Films are listed under the…

  20. Particle film technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Particle Film Technology involves establishing a mineral particle film on the surface of a plant or plant product that: (1) is chemically inert, (2) has a mean particle diameter < 2 um, (3) is formulated to spread and create a uniform film, (4) does not physically disrupt gas exchange from the le...

  1. Health Careers Film Guide.

    ERIC Educational Resources Information Center

    National Institutes of Health (DHEW), Bethesda, MD. Bureau of Health Manpower Education.

    This document, which represents a survey of the entire health career film field, was designed to provide information for people interested in a health career. The guide indicates that a major criteria for film selection was recency; however, some older films that give a fairly accurate image of a profession were included, with some emphasis given…

  2. Getting into Film.

    ERIC Educational Resources Information Center

    London, Mel

    This book describes the various aspects of the film industry and the many jobs related to filmmaking, stressing that no "formula" exists for finding a successful career in the film industry. Chapters provide information on production, writing for film, cinematography, editing, music, sound, animation and graphics, acting and modeling, the "unsung…

  3. Pyrolyzed thin film carbon

    NASA Technical Reports Server (NTRS)

    Tai, Yu-Chong (Inventor); Liger, Matthieu (Inventor); Harder, Theodore (Inventor); Konishi, Satoshi (Inventor); Miserendino, Scott (Inventor)

    2010-01-01

    A method of making carbon thin films comprises depositing a catalyst on a substrate, depositing a hydrocarbon in contact with the catalyst and pyrolyzing the hydrocarbon. A method of controlling a carbon thin film density comprises etching a cavity into a substrate, depositing a hydrocarbon into the cavity, and pyrolyzing the hydrocarbon while in the cavity to form a carbon thin film. Controlling a carbon thin film density is achieved by changing the volume of the cavity. Methods of making carbon containing patterned structures are also provided. Carbon thin films and carbon containing patterned structures can be used in NEMS, MEMS, liquid chromatography, and sensor devices.

  4. UV actinometer film

    NASA Technical Reports Server (NTRS)

    Coulbert, C. D.; Gupta, A.; Pitts, J.

    1980-01-01

    Cumulative UV radiation can be measured by low-cost polymer film that is unaffacted by visible light. Useful for virtually any surface, film can help paint and plastics manufacturers determine how well their products stand up against UV radiation. Actinometer film uses photochemically sensitive compound that changes its chemical composition in response to solar radiation. Extent of chemical conversion depends on length exposure and can be measured by examining film sample with spectrophotometer. Film can be exposed from several seconds up to month.

  5. Chronicles of foam films.

    PubMed

    Gochev, G; Platikanov, D; Miller, R

    2016-07-01

    The history of the scientific research on foam films, traditionally known as soap films, dates back to as early as the late 17th century when Boyle and Hooke paid special attention to the colours of soap bubbles. Their inspiration was transferred to Newton, who began systematic study of the science of foam films. Over the next centuries, a number of scientists dealt with the open questions of the drainage, stability and thickness of foam films. The significant contributions of Plateau and Gibbs in the middle/late 19th century are particularly recognized. After the "colours" method of Newton, Reinold and Rücker as well as Johhonnot developed optical methods for measuring the thickness of the thinner "non-colour" films (first order black) that are still in use today. At the beginning of the 20th century, various aspects of the foam film science were elucidated by the works of Dewar and Perrin and later by Mysels. Undoubtedly, the introduction of the disjoining pressure by Derjaguin and the manifestation of the DLVO theory in describing the film stability are considered as milestones in the theoretical development of foam films. The study of foam films gained momentum with the introduction of the microscopic foam film methodology by Scheludko and Exerowa, which is widely used today. This historical perspective serves as a guide through the chronological development of knowledge on foam films achieved over several centuries. PMID:26361708

  6. Depositing Diamondlike Carbon Films

    NASA Technical Reports Server (NTRS)

    Mirtich, M. J.; Sovey, J. S.; Banks, B. A.

    1986-01-01

    New process demonstrated to make thin films (usually thousands of angstroms to few microns thick) that have properties of diamonds. Various plasma and ion-beam techniques employed to generate films. Films made by radio-frequency plasma decomposition of hydrocarbon gas or other alkanes, by low-energy carbon-ion-beam deposition, or by ion plating and dual ion technique using carbon target. Advantages of new process over others are films produced, though amorphous, are clear, extremely hard, chemically inert, of high resistivity, and have index of refraction of 3.2 properties similar to those of single-crystal diamonds. Films have possible uses in microelectronic applications, high-energy-laser and plastic windows, corrosion protection for metals, and other applications where desired properties of film shaped during the film-formation process.

  7. Ceramic Composite Thin Films

    NASA Technical Reports Server (NTRS)

    Ruoff, Rodney S. (Inventor); Stankovich, Sasha (Inventor); Dikin, Dmitriy A. (Inventor); Nguyen, SonBinh T. (Inventor)

    2013-01-01

    A ceramic composite thin film or layer includes individual graphene oxide and/or electrically conductive graphene sheets dispersed in a ceramic (e.g. silica) matrix. The thin film or layer can be electrically conductive film or layer depending the amount of graphene sheets present. The composite films or layers are transparent, chemically inert and compatible with both glass and hydrophilic SiOx/silicon substrates. The composite film or layer can be produced by making a suspension of graphene oxide sheet fragments, introducing a silica-precursor or silica to the suspension to form a sol, depositing the sol on a substrate as thin film or layer, at least partially reducing the graphene oxide sheets to conductive graphene sheets, and thermally consolidating the thin film or layer to form a silica matrix in which the graphene oxide and/or graphene sheets are dispersed.

  8. Solution-based Syntheses of Iron Pyrite Thin Films for Photovoltaic and Protein Foot-printing Applications

    NASA Astrophysics Data System (ADS)

    El Makkaoui, Mohammed

    -printing application in collaboration with the Brenowitz lab at the Albert Einstein College of Medicine and the Khine lab at the University of California, Irvine. A thin film of pyrite nano-crystals is spray deposited (Video in supplementary ) onto a shape memory polymer that is then thermally treated with a heat gun, causing the sheet to retract and stiffen as the nanocrystalline layer crumples and integrates into the polyolefin, forming a mechanically robust and highly reactive laminate of pyrite nano-crystals. Micro-wells are thermoformed into the laminate under negative pressure. ˙OH dose-oxidation response relationship were established via varying the H2O 2 concentration and reaction time. The flexibility, cost effectiveness and scalability of this platform enables integration into macro-structural analysis systems. Pyrite shrink laminates and hydrazine ink films were characterized by Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Raman Spectroscopy. Drop deposition oxidation experiments and MALDI-TOF "Matrix Assisted Laser Desorption/Ionization-Time of Flight" Mass Spectroscopy of protein aliquots reacted on PSWL were conducted in the Brenowitz lab at the department of biochemistry at the Albert Einstein College of Medicine in New York.

  9. Documentary Elements in Early Films.

    ERIC Educational Resources Information Center

    Sanderson, Richard A.

    Focusing on documentary elements, this study examines the film content and film techniques of 681 motion pictures produced in the United States prior to 1904. Analysis of films by type, subject matter, and trends in subject matter shows that one-third of the early films are documentary in type and three-fourths of the films use subject matter of a…

  10. Film Music. Factfile No. 8.

    ERIC Educational Resources Information Center

    Elsas, Diana, Ed.; And Others

    Organizations listed here with descriptive information include film music clubs and music guilds and associations. These are followed by a representative list of schools offering film music and/or film sound courses. Sources are listed for soundtrack recordings, sound effects/production music, films on film music, and oral history programs. The…

  11. Books on Film and Filmmaking.

    ERIC Educational Resources Information Center

    Ruth, Deborah D.

    This annotated bibliography of books on film and filmmaking contains references on materials related to animation production, general reference materials, student film production, film study, experimental film, critics and directors, sources of funds for filmmaking, local resources, periodicals for filmmaking classes, sources of free films, and…

  12. Coating of plasma polymerized film

    NASA Technical Reports Server (NTRS)

    Morita, S.; Ishibashi, S.

    1980-01-01

    Plasma polymerized thin film coating and the use of other coatings is suggested for passivation film, thin film used for conducting light, and solid body lubrication film of dielectrics of ultra insulators for electrical conduction, electron accessories, etc. The special features of flow discharge development and the polymerized film growth mechanism are discussed.

  13. Evaporated VOx Thin Films

    NASA Astrophysics Data System (ADS)

    Stapinski, Tomasz; Leja, E.

    1989-03-01

    VOx thin films on glass were obtained by thermal evaporation of V205, powder. The structural investigations were carried out with the use of X-ray diffractometer. The electrical properties of the film were examined by means of temperature measurements of resistivity for the samples heat-treated in various conditions. Optical transmission and reflection spectra of VOX films of various composition showed the influence of the heat treatment.

  14. Renaissance of the Film.

    ERIC Educational Resources Information Center

    Bellone, Julius, Ed.

    The post-World War II period was one of the liveliest in the history of the cinema. This is a collection of 33 critical articles on some of the best films of the perd. Most of the essays explicate the themes and symbols of the films. The essays deal with these films: "The Apu Trilogy,""L'Avventura,""Balthazar,""Blow-Up,""Bonnie and Clyde," Citizen…

  15. Clinical careers film.

    PubMed

    2015-09-01

    Those interested in developing clinical academic careers might be interested in a short animated film by Health Education England (HEE) and the National Institute for Health Research. The three-minute film, a frame from which is shown below, describes the sort of opportunities that are on offer to all professionals as part of the HEE's clinical academic careers framework. You can view the film on YouTube at tinyurl.com/pelb95c. PMID:26309005

  16. Protective overcoating of films

    NASA Technical Reports Server (NTRS)

    Maas, K. A.

    1972-01-01

    Kodak Film Type SO-212 was emulsion overcoated with gelatin and lacquer to evaluate the feasibility of application of the coatings, any image degradation, and the relative protection offered against abrasion. Evaluated were: Eastman motion picture film lacquer Type 485, water solutions of Eastman purified Calfskin gelatin, and experimental Eastman gelatin stripping film of 4 and 6 microns. Conclusions reached were: (1) All coatings can be applied with relative ease with the only limitation being that of equipment. (2) None of the coatings degrade the processed image. (3) All of the coatings provide protection to the emulsion. These conclusions apply to any film which may be considered for overcoating.

  17. Nanocarbonic transparent conductive films.

    PubMed

    Roth, Siegmar; Park, Hye Jin

    2010-07-01

    This tutorial review discusses the contradictory material properties of electrical conductivity and optical transparency for the examples of graphene films and carbon nanotube networks. It is argued that for homogeneous films both properties are linked by basic laws of physics and that for perfect monoatomic layers conductivity and transparency can be calculated from the fine structure constant. To beat these limitations, inhomogeneous films are required, such as graphene with an array of holes or nanotube networks. An overview is given on literature values of transparency and conductivity, both for graphene films and for nanotube networks. PMID:20502813

  18. Historical film processing

    NASA Astrophysics Data System (ADS)

    Wu, Yi; Suter, David

    1995-08-01

    This paper describes work using historical film material, including what is believed to be the world's first feature length film. The digital processing of historical film material permits many new facilities: digital restoration, electronic storage, automated indexing, and electronic delivery to name a few. Although the work aims ultimately to support all of the previously mentioned facilities, this paper concentrated upon automatic scene change detection, brightness correction, and frame registration. These processes are fundamental to a more complete and complex processing system, but, by themselves, could be immediately used in computer-assisted film cataloging.

  19. The Possibility of Film Criticism.

    ERIC Educational Resources Information Center

    Poague, Leland; Cadbury, William

    1989-01-01

    Examines the role of critical language in film criticism. Compares and contrasts Monroe Beardsley's philosophy on film aesthetics with the New Criticism. Outlines some of the contributions Beardsley has made to the study of film criticism. (KM)

  20. Microfilm--Which Film Type, Which Application?

    ERIC Educational Resources Information Center

    Dodson, Suzanne Cates

    1985-01-01

    Report on characteristics of different kinds of microfilm available indicates proper film for specific needs. Silver halide and nonsilver films, diazo film, vesicular film, reaction of films to light, effect of heat and humidity on films, film susceptibility to scratching, and potential longevity of film types are covered. (35 references) (EJS)

  1. Film-Makers' Cooperative Catalogue Number Six.

    ERIC Educational Resources Information Center

    Film-Makers' Cooperative, New York, NY.

    The Film-Makers' Cooperative services as a film depository and rental agency for any film-makers who may choose to make their work available to the general public. Approximately 1,600 films are listed in film-maker sequence. Excerpts of film reviews are provided for each entry. An index by film title and policies and procedures for film rental are…

  2. Water depth penetration film test

    NASA Technical Reports Server (NTRS)

    Lockwood, H. E.; Perry, L.; Sauer, G. E.; Lamar, N. T.

    1974-01-01

    As part of the National Aeronautics and Space Administration Earth Resources Program, a comparative and controlled evaluation of nine film-filter combinations was completed to establish the relative effectiveness in recording water subsurface detail if exposed from an aerial platform over a typical water body. The films tested, with one exception, were those which prior was suggested had potential. These included an experimental 2-layer positive color film, a 2-layer (minus blue layer) film, a normal 3-layer color film, a panchromatic black-and-white film, and a black-and-white infrared film. Selective filtration was used with all films.

  3. Thin-film forces in pseudoemulsion films

    SciTech Connect

    Bergeron, V.; Radke, C.J. |

    1991-06-01

    Use of foam for enhanced oil recovery (EOR) has shown recent success in steam-flooding field applications. Foam can also provide an effective barrier against gas coning in thin oil zones. Both of these applications stem from the unique mobility-control properties a stable foam possesses when it exists in porous media. Unfortunately, oil has a major destabilizing effect on foam. Therefore, it is important for EOR applications to understand how oil destroys foam. Studies all indicate that stabilization of the pseudoemulsion film is critical to maintain foam stability in the presence of oil. Hence, to aid in design of surfactant formulations for foam insensitivity to oil the authors pursue direct measurement of the thin-film or disjoining forces that stabilize pseudoemulsion films. Experimental procedures and preliminary results are described.

  4. Film Making in Schools.

    ERIC Educational Resources Information Center

    Lowndes, Douglas

    A program which used practical film study to extend powers of observation and comment and to help young people (ages 12 through 16) develop an understanding of contemporary society is described in this manual. The role of film in school curricula and its integration with other studies is discussed in an opening section. The next section contains a…

  5. Film and the Humanities.

    ERIC Educational Resources Information Center

    O'Connor, John E., Ed.

    This report on a conference, which brought together representatives of various humanistic disciplines to explore the cross-disciplinary appeal of film study as well as the use of film in stimulating scholarship and teaching, includes a narrative summary of the day's conversations and issues raised, as well as of reprints of articles that suggest…

  6. Filming for Television.

    ERIC Educational Resources Information Center

    Englander, A. Arthur; Petzold, Paul

    Film makers, professional or amateur, will find in this volume an extensive discussion of the adaptation of film technique to television work, of the art of the camera operator, and of the productive relationships between people, organization, and hardware. Chapters include "The Beginnings," an overview of the interrelationship between roles in…

  7. Stabilized chromium oxide film

    DOEpatents

    Garwin, Edward L.; Nyaiesh, Ali R.

    1988-01-01

    Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150.ANG. are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

  8. On Teaching Ethnographic Film

    ERIC Educational Resources Information Center

    Clarfield, Geoffrey

    2013-01-01

    The author of this article, a developmental anthropologist, illustrates how the instructor can use ethnographic films to enhance the study of anthropology and override notions about the scope and efficacy of Western intervention in the Third World, provided the instructor places such films in their proper historical and cultural context. He…

  9. Film Canister Science

    ERIC Educational Resources Information Center

    Ferstl, Andrew; Schneider, Jamie L.

    2007-01-01

    Opaque film canisters are readily available, cheap, and useful for scientific inquiry in the classroom. They can also be surprisingly versatile and useful as a tool for stimulating scientific inquiry. In this article, the authors describe inquiry activities using film canisters for preservice teachers, including a "black box" activity and several…

  10. Protolytic carbon film technology

    SciTech Connect

    Renschler, C.L.; White, C.A.

    1996-04-01

    This paper presents a technique for the deposition of polyacrylonitrile (PAN) on virtually any surface allowing carbon film formation with only the caveat that the substrate must withstand carbonization temperatures of at least 600 degrees centigrade. The influence of processing conditions upon the structure and properties of the carbonized film is discussed. Electrical conductivity, microstructure, and morphology control are also described.

  11. Thick film hydrogen sensor

    DOEpatents

    Hoffheins, Barbara S.; Lauf, Robert J.

    1995-01-01

    A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors.

  12. Thick film hydrogen sensor

    DOEpatents

    Hoffheins, B.S.; Lauf, R.J.

    1995-09-19

    A thick film hydrogen sensor element includes an essentially inert, electrically-insulating substrate having deposited thereon a thick film metallization forming at least two resistors. The metallization is a sintered composition of Pd and a sinterable binder such as glass frit. An essentially inert, electrically insulating, hydrogen impermeable passivation layer covers at least one of the resistors. 8 figs.

  13. Authors on Film.

    ERIC Educational Resources Information Center

    Geduld, Harry M., Ed.

    Different authors' attitudes toward film are revealed through five different sections of this book: (1) articles, essays, and reviews pertaining to the silent cinema and the transition to sound; (2) general statements on the film medium or filmmakers and their messages; (3) essays dealing with the problems, involvements, and reflections of the…

  14. Construction of Meaning: Film.

    ERIC Educational Resources Information Center

    Pryluck, Calvin

    1995-01-01

    Notes that film has no clear set of rules, unlike all languages, which are deductive systems interpreted according to clear sets of rules. Suggests that film is an inductive system whose interpretation is based on a general understanding of events depicted as modified by production variables such as lighting, camera angles, and the context of…

  15. Stabilized chromium oxide film

    DOEpatents

    Nyaiesh, A.R.; Garwin, E.L.

    1986-08-04

    Stabilized air-oxidized chromium films deposited on high-power klystron ceramic windows and sleeves having a thickness between 20 and 150A are useful in lowering secondary electron emission yield and in avoiding multipactoring and window failure due to overheating. The ceramic substrate for the film is chosen from alumina, sapphire or beryllium oxide.

  16. Film Study Hang Ups.

    ERIC Educational Resources Information Center

    Grenier, Charles F.

    1969-01-01

    The interest and delight which students find in film should be preserved from a teacher's excessive zeal to analyze and explain. As the beauty of poetry is frequently diminished through exhaustive analyses of similes, rhyme schemes, and other technical devices, the value of film to high school students can be weakened through too great an emphasis…

  17. GPN Film Catalog 1972.

    ERIC Educational Resources Information Center

    Nebraska Univ., Lincoln. Great Plains National Instructional Television Library.

    The films described in this catalog were produced by schools or school-related organizations and were designed to meet the "relevant needs expressed by a broad spectrum of media personnel, students, and educators across the country." The catalog describes seventeen series and eight single films. For each of the series a description is presented…

  18. Elements of Film.

    ERIC Educational Resources Information Center

    Bobker, Lee R.

    A film is the successful combination of two distinct groups of elements: (1) the technical elements by which the film is made (camera, lighting, sound and editing) and (2) the esthetic elements that transform the craft into an art. This book attempts to combine the study of these elements by providing technical information about the process of…

  19. Creative Film-Making.

    ERIC Educational Resources Information Center

    Smallman, Kirk

    The fundamentals of motion picture photography are introduced with a physiological explanation for the illusion of motion in a film. Film stock formats and emulsions, camera features, and lights are listed and described. Various techniques of exposure control are illustrated in terms of their effects. Photographing action with a stationary or a…

  20. Dental Training Films.

    ERIC Educational Resources Information Center

    Veterans Administration Medical Center, Washington, DC.

    This dental training films catalog is organized into two sections. Section I is a category listing of the films by number and title, indexed according to generalized headings; categories are as follow: anatomy, articulator systems, complete dentures, dental assisting, dental laboratory technology, dental materials, dental office emergencies,…

  1. FAA Film Catalog.

    ERIC Educational Resources Information Center

    Federal Aviation Administration (DOT), Washington, DC.

    Some 75 films from the U.S. Department of Transportation's Federal Aviation Administration are listed in this catalog. Topics dealt with include aerodynamics, airports, aviation history and careers, flying clubs, navigation and weather. Most of the films are 16mm sound and color productions. Filmstrips requiring a 35mm projector and phonograph or…

  2. Critical Approaches to Film.

    ERIC Educational Resources Information Center

    Bywater, Timothy Robert

    This study deals primarily with recent academically oriented critical material, but it also embraces the range of film criticism that has been written for the mass audience in newspapers and periodicals. The study considers eight types of critical approaches to analyzing film: the journalistic approach, which contains both a reportorial-review and…

  3. Determining Film Art.

    ERIC Educational Resources Information Center

    Bullis, Roger

    1974-01-01

    The criteria by which films can and should be analyzed as art are discussed in this paper. A triangular model of theme-form-content is presented with form given greater significance than is usually the case in film criticism. The form-content-theme synthesis is the process in which theme is made clear by means of form and content within an…

  4. Films and Feelings.

    ERIC Educational Resources Information Center

    Gaffney, Maureen, Ed.

    1981-01-01

    Children's emotional responses to films are the focus of the four articles in this issue designed for media specialists and educators. Following an editorial discussing the responsibilities of media as put forth by Bruno Bettleheim, the first article presents a methodology and rationale for using story films to encourage children's exploration of…

  5. Discovery in Film.

    ERIC Educational Resources Information Center

    Heyer, Robert; Meyer, Anthony

    Seventy-eight "classic" short, non-feature films, cataloged according to six themes--communication, freedom, love, peace, happiness, and the underground--are discussed in this guide. The standard critique for each film has a fourfold purpose: (1) to indicate content and style; (2) to pose questions which provoke discussion; (3) to suggest resource…

  6. Abstract Film and Beyond.

    ERIC Educational Resources Information Center

    Le Grice, Malcolm

    A theoretical and historical account of the main preoccupations of makers of abstract films is presented in this book. The book's scope includes discussion of nonrepresentational forms as well as examination of experiments in the manipulation of time in films. The ten chapters discuss the following topics: art and cinematography, the first…

  7. Selective inorganic thin films

    SciTech Connect

    Phillips, M.L.F.; Weisenbach, L.A.; Anderson, M.T.

    1995-05-01

    This project is developing inorganic thin films as membranes for gas separation applications, and as discriminating coatings for liquid-phase chemical sensors. Our goal is to synthesize these coatings with tailored porosity and surface chemistry on porous substrates and on acoustic and optical sensors. Molecular sieve films offer the possibility of performing separations involving hydrogen, air, and natural gas constituents at elevated temperatures with very high separation factors. We are focusing on improving permeability and molecular sieve properties of crystalline zeolitic membranes made by hydrothermally reacting layered multicomponent sol-gel films deposited on mesoporous substrates. We also used acoustic plate mode (APM) oscillator and surface plasmon resonance (SPR) sensor elements as substrates for sol-gel films, and have both used these modified sensors to determine physical properties of the films and have determined the sensitivity and selectivity of these sensors to aqueous chemical species.

  8. Bursting of soap films

    NASA Astrophysics Data System (ADS)

    Chowdhury, Debashish; Stauffer, Dietrich

    1992-07-01

    Soap films consist of thin films of water in between two monolayers of amphiphilic molecules. Newton black films (NBFs) are the thinnest possible soap films. We have developed a microscopic model of NBFs; this model is a variant of the Widom model for microemulsions. By carrying out Monte Carlo simulations of this model, we have investigated the dependence of the lifetime of the NBFs on (a) the initial concentration of the amphiphilic molecules, (b) the temperature and (c) the bending rigidity of the constituent amphiphilic monolayers. We compare our results with the corresponding experimental observations and suggest further specific experiments. We establish that the “edge energy” of the model bilayer tends to stabilize the NBF; a similar mechanism leads to the well known phenomenon of “self-healing” of small enough holes in pierced vesicles. We also review the laws of growth of holes in soap films during rupture. Finally, we speculate on some other possible applications of our ideas.

  9. The National Film Registry: Acquiring Our Film Heritage.

    ERIC Educational Resources Information Center

    Ziegler, Roy A.

    The National Film Registry, which is primarily a designated list of films to be preserved by the Library of Congress, is also a valuable tool for selecting "films that are culturally, historically, and aesthetically significant." Following a brief discussion of the history and selection process of the National Film Registry, Southeast Missouri…

  10. Chiral atomically thin films

    NASA Astrophysics Data System (ADS)

    Kim, Cheol-Joo; Sánchez-Castillo, A.; Ziegler, Zack; Ogawa, Yui; Noguez, Cecilia; Park, Jiwoong

    2016-06-01

    Chiral materials possess left- and right-handed counterparts linked by mirror symmetry. These materials are useful for advanced applications in polarization optics, stereochemistry and spintronics. In particular, the realization of spatially uniform chiral films with atomic-scale control of their handedness could provide a powerful means for developing nanodevices with novel chiral properties. However, previous approaches based on natural or grown films, or arrays of fabricated building blocks, could not offer a direct means to program intrinsic chiral properties of the film on the atomic scale. Here, we report a chiral stacking approach, where two-dimensional materials are positioned layer-by-layer with precise control of the interlayer rotation (θ) and polarity, resulting in tunable chiral properties of the final stack. Using this method, we produce left- and right-handed bilayer graphene, that is, a two-atom-thick chiral film. The film displays one of the highest intrinsic ellipticity values (6.5 deg μm–1) ever reported, and a remarkably strong circular dichroism (CD) with the peak energy and sign tuned by θ and polarity. We show that these chiral properties originate from the large in-plane magnetic moment associated with the interlayer optical transition. Furthermore, we show that we can program the chiral properties of atomically thin films layer-by-layer by producing three-layer graphene films with structurally controlled CD spectra.

  11. Chiral atomically thin films.

    PubMed

    Kim, Cheol-Joo; Sánchez-Castillo, A; Ziegler, Zack; Ogawa, Yui; Noguez, Cecilia; Park, Jiwoong

    2016-06-01

    Chiral materials possess left- and right-handed counterparts linked by mirror symmetry. These materials are useful for advanced applications in polarization optics, stereochemistry and spintronics. In particular, the realization of spatially uniform chiral films with atomic-scale control of their handedness could provide a powerful means for developing nanodevices with novel chiral properties. However, previous approaches based on natural or grown films, or arrays of fabricated building blocks, could not offer a direct means to program intrinsic chiral properties of the film on the atomic scale. Here, we report a chiral stacking approach, where two-dimensional materials are positioned layer-by-layer with precise control of the interlayer rotation (θ) and polarity, resulting in tunable chiral properties of the final stack. Using this method, we produce left- and right-handed bilayer graphene, that is, a two-atom-thick chiral film. The film displays one of the highest intrinsic ellipticity values (6.5 deg μm(-1)) ever reported, and a remarkably strong circular dichroism (CD) with the peak energy and sign tuned by θ and polarity. We show that these chiral properties originate from the large in-plane magnetic moment associated with the interlayer optical transition. Furthermore, we show that we can program the chiral properties of atomically thin films layer-by-layer by producing three-layer graphene films with structurally controlled CD spectra. PMID:26900756

  12. Film Scriptwriting: A Practical Manual.

    ERIC Educational Resources Information Center

    Swain, Dwight V.

    Dealing with both documentary and feature films, this book is a guide to using particular tools and procedures in developing ideas and concepts for writing film scripts. Part one deals with the factual, or documentary, film and discusses the proposal outline, film treatment, sequence outline, shooting script, and narration writing. Part two…

  13. Using Films in Literature Courses.

    ERIC Educational Resources Information Center

    Littell, Katherine M.

    1976-01-01

    Films are becoming recognized as an important medium of foreign language instruction. Although there is a lack of instructional films in German, an abundance of excellent feature films is available through the German Embassy and various consulates. Well-edited scenarios are needed, however, in order to make using these films an effective teaching…

  14. The Art of the Film.

    ERIC Educational Resources Information Center

    Lindgren, Ernest

    The author prefaces his consideration of films as an art form with a discussion of the mechanics of filmmaking. He describes the division of talent on a movie set, details the history of the tools of filmmakers, and explains the production and reproduction of a film. The influence of film techniques on plot development in a fiction film is…

  15. Discovery in Film, Book Two.

    ERIC Educational Resources Information Center

    Gordon, Malcolm W.

    Approximately 80 16 millimeter (16mm) short films are reviewed in this introduction and guide which attempts to be comprehensive in touching the major areas and styles of 16mm films now being produced. An attempt is made to describe as carefully as possible the style and content of each film and suggest ways in which the films might be used. Films…

  16. Diagnosing Disputes in Film Criticism.

    ERIC Educational Resources Information Center

    Schultz, Robert A.

    1979-01-01

    By classifying and analyzing actual disputes in film criticism, the author considers the following questions: Are there connections between film theory and film criticism? If so, which are healthy and which are diseased? If not, what alternative healthy function might film theory have? (Author/SJL)

  17. Biomimetic thin film synthesis

    SciTech Connect

    Graff, G.L.; Campbell, A.A.; Gordon, N.R.

    1995-05-01

    The purpose of this program is to develop a new process for forming thin film coatings and to demonstrate that the biomimetic thin film technology developed at PNL is useful for industrial applications. In the biomimetic process, mineral deposition from aqueous solution is controlled by organic functional groups attached to the underlying substrate surface. The coatings process is simple, benign, inexpensive, energy efficient, and particularly suited for temperature sensitive substrate materials (such as polymers). In addition, biomimetic thin films can be deposited uniformly on complex shaped and porous substrates providing a unique capability over more traditional line-of-sight methods.

  18. Negative birefringent polyimide films

    NASA Technical Reports Server (NTRS)

    Harris, Frank W. (Inventor); Cheng, Stephen Z. D. (Inventor)

    1994-01-01

    A negative birefringent film, useful in liquid crystal displays, and a method for controlling the negative birefringence of a polyimide film is disclosed which allows the matching of an application to a targeted amount of birefringence by controlling the degree of in-plane orientation of the polyimide by the selection of functional groups within both the diamine and dianhydride segments of the polyimide which affect the polyimide backbone chain rigidity, linearity, and symmetry. The higher the rigidity, linearity and symmetry of the polyimide backbone, the larger the value of the negative birefringence of the polyimide film.

  19. Thin film hydrogen sensor

    DOEpatents

    Cheng, Y.T.; Poli, A.A.; Meltser, M.A.

    1999-03-23

    A thin film hydrogen sensor includes a substantially flat ceramic substrate with first and second planar sides and a first substrate end opposite a second substrate end; a thin film temperature responsive resistor on the first planar side of the substrate proximate to the first substrate end; a thin film hydrogen responsive metal resistor on the first planar side of the substrate proximate to the fist substrate end and proximate to the temperature responsive resistor; and a heater on the second planar side of the substrate proximate to the first end. 5 figs.

  20. Ultrahard carbon nanocomposite films

    SciTech Connect

    SIEGAL,MICHAEL P.; TALLANT,DAVID R.; PROVENCIO,PAULA P.; OVERMYER,DONALD L.; SIMPSON,REGINA L.; MARTINEZ-MIRANDA,L.J.

    2000-01-27

    Modest thermal annealing to 600 C of diamondlike amorphous-carbon (a-C) films grown at room temperature results in the formation of carbon nanocomposites with hardness similar to diamond. These nanocomposite films consist of nanometer-sized regions of high density a-C embedded in an a-C matrix with a reduced density of 5--10%. The authors report on the evolution of density and bonding topologies as a function of annealing temperature. Despite a decrease in density, film hardness actually increases {approximately} 15% due to the development of the nanocomposite structure.

  1. Thin film hydrogen sensor

    DOEpatents

    Cheng, Yang-Tse; Poli, Andrea A.; Meltser, Mark Alexander

    1999-01-01

    A thin film hydrogen sensor, includes: a substantially flat ceramic substrate with first and second planar sides and a first substrate end opposite a second substrate end; a thin film temperature responsive resistor on the first planar side of the substrate proximate to the first substrate end; a thin film hydrogen responsive metal resistor on the first planar side of the substrate proximate to the fist substrate end and proximate to the temperature responsive resistor; and a heater on the second planar side of the substrate proximate to the first end.

  2. Nanostructured thermoplastic polyimide films

    SciTech Connect

    Aglan, Heshmat

    2015-05-19

    Structured films containing multi-walled carbon nanotubes ("MWCNTs") have enhanced mechanical performance in terms of strength, fracture resistance, and creep recovery of polyimide ("PI") films. Preferably, the loadings of MWCNTs can be in the range of 0.1 wt % to 0.5 wt %. The strength of the new PI films dried at 60.degree. C. increased by 55% and 72% for 0.1 wt % MWCNT and 0.5 wt % MWCNT loadings, respectively, while the fracture resistance increased by 23% for the 0.1 wt % MWCNTs and then decreases at a loading of 0.5 wt % MWCNTs. The films can be advantageously be created by managing a corresponding shift in the annealing temperature at which the maximum strength occurs as the MWCNT loadings increase.

  3. Amorphous diamond films

    DOEpatents

    Falabella, S.

    1998-06-09

    Amorphous diamond films having a significant reduction in intrinsic stress are prepared by biasing a substrate to be coated and depositing carbon ions thereon under controlled temperature conditions. 1 fig.

  4. Magnetron sputtered boron films

    DOEpatents

    Makowiecki, Daniel M.; Jankowski, Alan F.

    1998-01-01

    A method is described for the production of thin boron and titanium/boron films by magnetron sputter deposition. The amorphous boron films contain no morphological growth features, unlike those found when thin films are prepared by various physical vapor deposition processes. Magnetron sputter deposition method requires the use of a high density crystalline boron sputter target which is prepared by hot isostatic pressing. Thin boron films prepared by this method are useful for producing hardened surfaces, surfacing machine tools, etc. and for ultra-thin band pass filters as well as the low Z element in low Z/high Z optical components, such as mirrors which enhance reflectivity from grazing to normal incidence.

  5. Magnetron sputtered boron films

    DOEpatents

    Makowiecki, D.M.; Jankowski, A.F.

    1998-06-16

    A method is described for the production of thin boron and titanium/boron films by magnetron sputter deposition. The amorphous boron films contain no morphological growth features, unlike those found when thin films are prepared by various physical vapor deposition processes. Magnetron sputter deposition method requires the use of a high density crystalline boron sputter target which is prepared by hot isostatic pressing. Thin boron films prepared by this method are useful for producing hardened surfaces, surfacing machine tools, etc. and for ultra-thin band pass filters as well as the low Z element in low Z/high Z optical components, such as mirrors which enhance reflectivity from grazing to normal incidence. 8 figs.

  6. Sprites on Film

    NASA Video Gallery

    Filmed at 10,000 frames per second by Japan's NHK television, movies like this of electromagnetic bursts called "sprites" will help scientists better understand how weather high in the atmosphere r...

  7. TAMPERPROOF FILM BADGE

    DOEpatents

    Kocher, L.F.

    1958-10-01

    A persornel dosimeter film badge made of plastic, with provision for a picture of the wearer and an internal slide containing photographic film that is sensitive to various radiations, is described. Four windows made of differing material selectively attenuate alpha, beta, gamma rays, and neutrons so as to distinguish the particular type of radiation the wearer was subjected to. In addition, a lead shield has the identification number of the wearer perforated thereon so as to identify the film after processing. An internal magnetically actuated latch securely locks the slide within the body, and may be withdrawn only upon the external application of two strong magnetic forces in order to insure that the wearer or other curious persons will not accidentally expose the film to visual light.

  8. Quantitative film radiography

    SciTech Connect

    Devine, G.; Dobie, D.; Fugina, J.; Hernandez, J.; Logan, C.; Mohr, P.; Moss, R.; Schumacher, B.; Updike, E.; Weirup, D.

    1991-02-26

    We have developed a system of quantitative radiography in order to produce quantitative images displaying homogeneity of parts. The materials that we characterize are synthetic composites and may contain important subtle density variations not discernible by examining a raw film x-radiograph. In order to quantitatively interpret film radiographs, it is necessary to digitize, interpret, and display the images. Our integrated system of quantitative radiography displays accurate, high-resolution pseudo-color images in units of density. We characterize approximately 10,000 parts per year in hundreds of different configurations and compositions with this system. This report discusses: the method; film processor monitoring and control; verifying film and processor performance; and correction of scatter effects.

  9. Polymer film composite transducer

    DOEpatents

    Owen, Thomas E.

    2005-09-20

    A composite piezoelectric transducer, whose piezoeletric element is a "ribbon wound" film of piezolectric material. As the film is excited, it expands and contracts, which results in expansion and contraction of the diameter of the entire ribbon winding. This is accompanied by expansion and contraction of the thickness of the ribbon winding, such that the sound radiating plate may be placed on the side of the winding.

  10. Multifunctional thin film surface

    SciTech Connect

    Brozik, Susan M.; Harper, Jason C.; Polsky, Ronen; Wheeler, David R.; Arango, Dulce C.; Dirk, Shawn M.

    2015-10-13

    A thin film with multiple binding functionality can be prepared on an electrode surface via consecutive electroreduction of two or more aryl-onium salts with different functional groups. This versatile and simple method for forming multifunctional surfaces provides an effective means for immobilization of diverse molecules at close proximities. The multifunctional thin film has applications in bioelectronics, molecular electronics, clinical diagnostics, and chemical and biological sensing.