Butamax (United States)

<div class="section abstract"><div class="htmlview paragraph">The compatibility of elastomeric materials used in fuel storage and dispensing applications was determined for test fuels representing neat gasoline and gasoline blends containing 10 and 17 vol.% ethanol, and 16 and 24 vol.% isobutanol. The actual test fuel chemistries were based on the aggressive formulations described in SAE J1681 for oxygenated gasoline. Elastomer specimens of fluorocarbon, fluorosilicone, acrylonitrile rubber (NBR), polyurethane, neoprene, styrene butadiene rubber (SBR) and silicone were exposed to the test fuels for 4 weeks at 60°C. After measuring the wetted volume and hardness, the specimens were dried for 20 hours at 60°C and then remeasured for volume and hardness. Dynamic mechanical analysis (DMA) was also performed to determine the glass transition temperature (T<sub>g</sub>).</div><div class="htmlview paragraph">Comparison to the original values showed that all elastomer materials experienced volume expansion and softening when wetted by the test fuels. The fluorocarbons underwent the least amount of swelling (<25 %) while the SBR and silicone samples exhibited the highest level of expansion (>100%). The level of swelling for each elastomer was higher for the test fuels containing the alcohol additions. In general, ethanol produced slightly higher swell than the oxygen equivalent level of isobutanol. When dried, the fluorocarbon specimens were slightly swollen (relative to the baseline values) due to fuel retention. The NBRs and neoprene exhibited shrinkage and embrittlement associated with the extraction of plasticizers. SBR also experienced shrinkage (after drying) but its hardness returned to the baseline value. The dried volumes (and hardness values) of the silicone, SBR and fluorosilicone rubbers closely matched their original values, but the polyurethane specimen showed degradation with exposure to the test fuels containing ethanol or isobutanol. The DMA results showed that the test fuels effectively decreased T<sub>g</sub> for the fluorocarbons, but increased T<sub>g</sub> for the NBR materials. The T<sub>g</sub> values other elastomers were not affected by the test fuels.</div></div>

<div class="section abstract"><div class="htmlview paragraph">Findings from an intermediate ambient temperature vehicle driveability study for isobutanol gasoline blends are reported. The pattern for the study was Coordinating Research Council Project CM-138-02, which investigated the effects of ethanol on cold-start/warm-up performance and Driveability Index. Objectives of the present study were: (a) to evaluate the efficacy of the current ASTM Driveability Index (DI) in predicting cold-start and warm-up driveability performance for isobutanol gasolines and (b) if required, identify modifications to the DI definition and specification limits for isobutanol blends. The test fuel matrix included fifteen fuels with nominal vapor pressures of 55 kPa (8 psi) at DI levels of 1150, 1200, 1250, and 1300 and isobutanol concentrations of 0, 16, and 24 volume percent. Twelve port- and direct-fuel-injected vehicles, which included US Tier 2 passenger cars and light-duty trucks from model years 2005 through 2008, were used to evaluate the test fuels. Cold-start and warm-up driveability tests were conducted at 4°C (40°F) following CRC E28 procedures as modified for all-weather chassis dynamometer implementation. As found in previous studies, cold-start and warm-up driveability performance deteriorated sharply for all fuels at DI levels above 1250. The present study also found the current DI relationship insufficient for predicting the driveability performance of isobutanol-blended fuels. A new driveability performance model was developed which successfully compensates for isobutanol and collapses to the traditional DI relationship when isobutanol is absent. Current ASTM specifications for maximum DI were found to be appropriate for the new relationship as well. Results from this study will provide useful guidelines for blending isobutanol fuels with good cold-start and warm-up driveability performance.</div></div>

<div>The compatibilities of fuel system elastomers and plastics were evaluated for test fuels containing 16 vol.% isobutanol (iBu16) and 10 vol.% ethanol (E10). Elastomers included two fluorocarbons, four acrylonitrile butadiene rubbers (NBRs), and one type of fluorosilicone, neoprene, and epichlorohydrin/ethylene oxide. Plastic materials included four nylon grades, three polyamides, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), ethylene tetrafluoroethylene (ETFE), polyphenylene sulfide (PPS), high-density polyethylene (HDPE), polybutylene terephthalate (PBT), polyoxymethylene (POM), flexible polyvinylchloride (PVC), polyetherimide (PEI), polyetheretherketone (PEEK), and a phenol formaldehyde reinforced with glass fiber (GFPF). For each polymer material, the volume, mass, and hardness were measured before and after drying. Dynamic mechanical analysis (DMA) measurements were also performed on the dried specimens.</div> <div>For the elastomer materials the measured properties were similar for both fuels. The fluorocarbons and fluorosilicone swelled the least (~20%), while more moderate (20-45%) expansion occurred for the two NBR hose grades and (ECO). HNBR, neoprene, and silicone exhibited high swelling and softening, which likely precludes their use in many fuel systems. For the plastic materials, the observed swell was low; Nylon 11 swelled around 15%, but otherwise, their measured swell was <10%. Many of the plastics also showed sensitivity to alcohol type, as the E10 test fuel often imparted appreciably higher swell than iBu16. In general, the plastic materials showed good compatibility with the iBu16 and E10 test fuels. The sole exception was the PVC material, which was structurally degraded from exposure to either fuel type. Compositional analysis showed high fuel retention in Nylon 12 and PVC. PVC also experienced a significant reduction in plasticizer compounds following exposure, which resulted in embrittlement and an increase in the glass-to-rubber transition temperature.</div>

Saccharomyces cerevisiae genetically engineered to enhance butanol production will be used in a manufacturing process similar to that of fuel ethanol production, including co-production of distillers products for animal feed. A poultry feeding trial was conducted with simulated isobutanol-derived dried distillers grains with solubles (bDDGS), comprising non-fermentable corn solids and heat-inactivated Butamax modified yeast (BMY), to determine potential health effects. Simulated dried distillers grains were produced in 2 variants: bDDGS containing 10% (B10) or 50% (B50) BMY. The BMY concentrations were selected based on a conservative estimate from ethanol-derived distillers grains (eDDGS) approximating 2.5 and 12-fold margins of exposure. The B10 and B50 DDGS were evaluated in a 42-day feeding trial using male Ross 708 broiler chickens fed diets containing eDDGS, B50 DDGS, or B10 DDGS without or with isobutanol, 2,3-butanediol, and isobutyric acid metabolites each at target concentrations of 2 (B10-2), 5 (B10-5), or 10 (B10-10) times the anticipated specification limit in the commercial product. Diets were fed (n = 50 broilers/treatment) in 3 phases: starter phase with 8% DDGS and grower and finisher phases each with 15% DDGS. No statistically significant differences or diet-related effects on mortality, clinical pathology, or organ weights, and no microscopic observations associated with consumption of diets containing B10, B50, or B10 supplemented with metabolites at any targeted exposure level were observed. A lower (P < 0.05) mean absolute bursa of Fabricius weight in the B10-10 group compared to the B10 group was considered to be within the range of biological variability. A non-significant trend toward lower weight, gains, and feed intake, and higher feed:gain ratio was observed in the B10-10 group, and was considered a non-adverse palatability effect of consuming high concentrations of metabolites. These results demonstrate that consumption of phase diets containing simulated DDGS from a novel isobutanol production process was well-tolerated.

&lt;div class="section abstract"&gt;&lt;div class="htmlview paragraph"&gt;In the past decade, a significant market has emerged for automotive fuels produced from renewable sources. Blends containing low concentrations of ethanol have been the readily-available choice for providing renewable content in gasoline fuels.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;The simple addition of ethanol to gasoline significantly increases the mixture's vapor pressure, which can promote higher vehicle evaporative emissions. Gasoline specifications and blending practices have been updated to help offset the increase to vapor pressure and evaporative emissions. However, recent studies have shown that even at reduced vapor pressure, ethanol can increase gasoline evaporative emissions by enhancing the permeation of hydrocarbons through the elastomeric materials found in vehicle fuel systems.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;Technology is currently in development that will allow for the production of isobutanol from renewable sources. In addition to high energy density, high octane, and good material compatibility, isobutanol has low vapor pressure impact when blended with gasoline and hence, low potential to drive evaporative emissions. However, until recently the impact of isobutanol to permeation emissions had not been determined.&lt;/div&gt;&lt;div class="htmlview paragraph"&gt;A test program was initiated in 2007 to explore the permeation effects of using isobutanol in gasoline in place of ethanol. The study compared seven isobutanol and ethanol blends at varying concentrations while matching fuel properties such as vapor pressure, aromatics, distillation and oxygen content. Testing was conducted using fuel systems removed from seven vehicles representing three technology groups across model years 1981 through 2006. The program duplicated the Coordinated Research Council (CRC) E-65-3 study protocols which quantified the permeation impacts of MTBE (Methyl Tertiary Butyl Ether) and ethanol. The fuel systems were removed from the vehicles and mounted on custom aluminum frames in positions closely approximating the vehicle layout. The fuel system rigs were then exposed to each fuel until the permeation emissions were stable over a three week average. Permeation emissions were measured in an emissions test SHED (Sealed Housing for Evaporative Determination) at 105°F (40.6°C). After stabilization has been determined, the rigs were placed in a variable temperature SHED (VT-SHED) and tested on the California two-day diurnal (65°F - 105°F, 18.3°C - 40.6°C) to determine the permeation impact of each fuel. The results confirm that isobutanol can be used in gasoline with reduced impact on fuel permeation emissions.&lt;/div&gt;&lt;/div&gt;

Computing connected components (CC) is a core operation on graph data. Since billion-scale graphs cannot be resident in memory of a single machine, there have been proposed a number of distributed graph processing methods. The representative ones for CC are Hash-To-Min and PowerGraph. Hash-To-Min focuses on minimizing the number of MapReduce rounds, but is still slower than in-memory methods, PowerGraph is a fast and general in-memory graph method, but requires a lot of machines for handling billion-scale graphs. We propose an ultra-fast parallel method DSP-CC, using only a single PC that exploits secondary storage like a PCI-E SSD for handling billion-scale graphs. It can compute connected components I/O efficiently using only a limited size of memory. Our experimental results show that DSP-CC significantly outperforms the representative methods including Hash-To-Min and PowerGraph.

In patients with dentofacial deformities, the most frequent aesthetic deficits are attributable to an underdevelopment of hard and soft tissues. The surgeon should consider not only traditional osteotomies, but also soft-tissue improving procedures, such as lipofilling or buccal fat removal to achieve better aesthetic results. The authors herein describe a simple, safe, and convenient technique for removal or transposition of the buccal fat pad (BFP) during minimally invasive orthognathic surgery (MIOS).