28 research outputs found

    Energy Efficiency Analysis: Biomass-to-Wheel Efficiency Related with Biofuels Production, Fuel Distribution, and Powertrain Systems

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    BACKGROUND: Energy efficiency analysis for different biomass-utilization scenarios would help make more informed decisions for developing future biomass-based transportation systems. Diverse biofuels produced from biomass include cellulosic ethanol, butanol, fatty acid ethyl esters, methane, hydrogen, methanol, dimethyether, Fischer-Tropsch diesel, and bioelectricity; the respective powertrain systems include internal combustion engine (ICE) vehicles, hybrid electric vehicles based on gasoline or diesel ICEs, hydrogen fuel cell vehicles, sugar fuel cell vehicles (SFCV), and battery electric vehicles (BEV). METHODOLOGY/PRINCIPAL FINDINGS: We conducted a simple, straightforward, and transparent biomass-to-wheel (BTW) analysis including three separate conversion elements--biomass-to-fuel conversion, fuel transport and distribution, and respective powertrain systems. BTW efficiency is a ratio of the kinetic energy of an automobile's wheels to the chemical energy of delivered biomass just before entering biorefineries. Up to 13 scenarios were analyzed and compared to a base line case--corn ethanol/ICE. This analysis suggests that BEV, whose electricity is generated from stationary fuel cells, and SFCV, based on a hydrogen fuel cell vehicle with an on-board sugar-to-hydrogen bioreformer, would have the highest BTW efficiencies, nearly four times that of ethanol-ICE. SIGNIFICANCE: In the long term, a small fraction of the annual US biomass (e.g., 7.1%, or 700 million tons of biomass) would be sufficient to meet 100% of light-duty passenger vehicle fuel needs (i.e., 150 billion gallons of gasoline/ethanol per year), through up to four-fold enhanced BTW efficiencies by using SFCV or BEV. SFCV would have several advantages over BEV: much higher energy storage densities, faster refilling rates, better safety, and less environmental burdens

    CUTANEOUS SEBACEOUS GLAND CARCINOMA IN THE POSTAURICULAR REGION

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    Carcinomas of the sebaceous glands of the skin are uncommon. These tumours metastasize frequently. A case of cutaneous sebaceous carcinoma localized in the postauricular region is presented with its exceptional large size and very poor prognosis

    <i>Fournier&#x2032;s gangrene</i>: Evaluation of 68 patients and analysis of prognostic variables

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    Context: Fournier&#x2032;s gangrene (FG) is a rapidly progressing acute gangrenous infection of the anorectal and urogenital area. Aims: The objectives of this study were to investigate patients with FG and to determine risk factors that affect mortality. Settings and Design: Retrospective clinical study. Materials and Methods: Clinical presentations and outcomes of surgical treatments were evaluated in 68 patients with FG. Statistical Analysis Used: Chi-square, Student&#x2032;s t -test, and logistic regression test. Results: Mean age of patients was 54 and female-to-male ratio was 9:59. Among the predisposing factors, diabetes mellitus (DM) was the most common ( n =24, 35.3&#x0025;), and sepsis on admission was detected in 31 (45.6&#x0025;) and 15 (22.1&#x0025;) patients, respectively. Seven (10.3&#x0025;) patients died. Using logistic regression test, Fournier&#x2032;s Gangrene Severity Index (FGSI)&#62; 9, DM and sepsis on admission were found as prognostic factors. Conclusions: FG has a high mortality rate, especially in patients with DM and sepsis. An FGSI value&#62; 9 indicates high mortality rate

    Fournier's gangrene: Evaluation of 68 patients and analysis of prognostic variables

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    Context: Fournier′s gangrene (FG) is a rapidly progressing acute gangrenous infection of the anorectal and urogenital area. Aims: The objectives of this study were to investigate patients with FG and to determine risk factors that affect mortality. Settings and Design: Retrospective clinical study. Materials and Methods: Clinical presentations and outcomes of surgical treatments were evaluated in 68 patients with FG. Statistical Analysis Used: Chi-square, Student′s t -test, and logistic regression test. Results: Mean age of patients was 54 and female-to-male ratio was 9:59. Among the predisposing factors, diabetes mellitus (DM) was the most common ( n =24, 35.3%), and sepsis on admission was detected in 31 (45.6%) and 15 (22.1%) patients, respectively. Seven (10.3%) patients died. Using logistic regression test, Fournier′s Gangrene Severity Index (FGSI)> 9, DM and sepsis on admission were found as prognostic factors. Conclusions: FG has a high mortality rate, especially in patients with DM and sepsis. An FGSI value> 9 indicates high mortality rate

    Advancing Towards a Hydrogen Energy Economy: Status, Opportunities and Barriers

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    Asia Pacific economic cooperation, automobiles, clean energy technology, economic development, energy security, environmental protection, fuel cells, hydrogen production, storage and transport, international energy agency, international partnership for the hydrogen economy,
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