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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 253 records · Page 14
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Support Induced Control of Surface Composition in Cu–Ni/TiO 2 Catalysts Enables High Yield Co-Conversion of HMF and Furfural to Methylated Furans

5-(hydroxymethyl)furfural (HMF) and furfural (FF) have been confirmed as valuable biomass-derived fuel precursors suitable for catalytic hydrodeoxygenation (HDO) to produce high octane fuel additives such dimethyl furan (DMF) and methyl furan (MF), respectively. In order to realize economically viable production of DMF and MF from biomass, catalytic processes with high yields, low catalyst costs, and process simplicity are needed. In this work, we demonstrate simultaneous co-processing of HMF and FF over Cu-Ni/TiO 2 catalysts, achieving 87.5% yield of DMF from HMF and 88.5% yield of MF from FF in a one pot reaction. The Cu-Ni/TiO 2 catalyst also exhibited improved stability and regeneration compared to Cu/TiO 2 and Cu/Al 2 O 3 catalysts for FF HDO, exhibiting a ~7% loss in FF conversion over 4 sequential recycles, compared to a ~50% loss in FF coversion for Cu/Al 2 O 3 and a ~30% loss in coversion for Cu/TiO 2 . Characterization of the Cu-Ni/TiO 2 catalyst by X-ray Photoelectron Spectroscopy, Scanning Transmission Electron Microscopy, and H 2 -Temperature Programmed Reduction and comparison to monometallic Cu and Ni on Al 2 O 3 and TiO 2 and bimetallic Cu-Ni/Al 2 O 3 catalysts suggest that the unique reactivity and stability of Cu-Ni/TiO 2 derives from support-induced metal segregation in which Cu is selectively enriched at the catalyst surface, while Ni is enriched at the TiO 2 interface. Our findings demonstrate that Cu-Ni/TiO 2 catalysts promise to be a catalyst system capable of integrating directly with a combined HMF and FF product stream from biomass processing to realize lower cost production of liquid fuels from biomass.

09 BIOMASS FUELS↗
DOE OSTI2012

Inverse Load Calculation of Wind Turbine Support Structures - A Numerical Verification Using the Comprehensive Simulation Code FAST: Preprint (Revised)

Physically measuring the dynamic responses of wind turbine support structures enables the calculation of the applied loads using an inverse procedure. In this process, inverse means deriving the inputs/forces from the outputs/responses. This paper presents results of a numerical verification of such an inverse load calculation. For this verification, the comprehensive simulation code FAST is used. FAST accounts for the coupled dynamics of wind inflow, aerodynamics, elasticity and turbine controls. Simulations are run using a 5-MW onshore wind turbine model with a tubular tower. Both the applied loads due to the instantaneous wind field and the resulting system responses are known from the simulations. Using the system responses as inputs to the inverse calculation, the applied loads arecalculated, which in this case are the rotor thrust forces. These forces are compared to the rotor thrust forces known from the FAST simulations. The results of these comparisons are presented to assess the accuracy of the inverse calculation. To study the influences of turbine controls, load cases in normal operation between cut-in and rated wind speed, near rated wind speed and between ratedand cut-out wind speed are chosen. The presented study shows that the inverse load calculation is capable of computing very good estimates of the rotor thrust. The accuracy of the inverse calculation does not depend on the control activity of the wind turbine.

17 WIND ENERGY↗
DOE OSTI2016

Open‐Pore Two‐Dimensional MFI Zeolite Nanosheets for the Fabrication of Hydrocarbon‐Isomer‐Selective Membranes on Porous Polymer Supports

Abstract Two‐dimensional zeolite nanosheets that do not contain any organic structure‐directing agents were prepared from a multilamellar MFI (ML‐MFI) zeolite. ML‐MFI was first exfoliated by melt compounding and then detemplated by treatment with a mixture of H 2 SO 4 and H 2 O 2 (piranha solution). The obtained OSDA‐free MFI nanosheets disperse well in water and can be used for coating applications. Deposits made on porous polybenzimidazole (PBI) supports by simple filtration of these suspensions exhibit an n ‐butane/isobutane selectivity of 5.4, with an n ‐butane permeance of 3.5×10 −7 mol m −2 s −1 Pa −1 (ca. 1000 GPU).

Zhang, Han↗
DOE OSTI2015

Application of Physiologically Based Pharmacokinetic (PBPK) Modeling to Support Dose Selection: Report of an FDA Public Workshop on PBPK: Physiologically Based Pharmacokinetic Modeling to Support Dose Selection

A workshop entitled “Application of Physiologically-based Pharmacokinetic (PBPK) Modeling to Support Dose Selection” was hosted on March 10, 2014 by the US Food and Drug Administration (FDA) at its White Oak Campus in Silver Spring, MD.1 The workshop endeavored to (i) assess the current state of knowledge in the application of PBPK in regulatory decision-making, and (ii) share and discuss best practices in the use of PBPK modeling to inform dose selection in specific patient populations. The conference benefited from strong and diverse participation from the FDA Center for Drug Evaluation and Research (CDER) leaders, European Medicine Agency (EMA) delegates, and pharmaceutical industry and academia representatives. The workshop commenced with plenary presentations by speakers from the FDA, industry, and academia. In the two panel sessions, detailed questions on the current status and future applications of PBPK in drug development and regulatory decisions were discussed. An important focus of the dialog was the need to better define what constitutes a credible physiological system and the evidentiary standards needed for using such a system in making regulatory decisions. This report provides a content summary of the workshop, based on plenary presentations and panel session transcripts posted on the FDA’s website.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2012

Matched-Pair Comparison of Radioembolization Plus Best Supportive Care Versus Best Supportive Care Alone for Chemotherapy Refractory Liver-Dominant Colorectal Metastases

Purpose: This study was designed to evaluate overall survival after radioembolization or best supportive care (BSC) in patients with chemotherapy-refractory liver-dominant metastatic colorectal cancer (mCRC). Methods: This was a matched-pair comparison of patients who received radioembolization plus BSC or BSC alone for extensive liver disease. Twenty-nine patients who received radioembolization were retrospectively matched with a contemporary cohort of >500 patients who received BSC from 3 centers in Germany. Using clinical databases, patients were initially matched for prior treatments and tumor burden and then 29 patients were consecutively identified with two or more of four matching criteria: synchronous/metachronous metastases, tumor burden, increased ALP, and/or CEA >200 U/ml. Survival was calculated from date of progression before radioembolization or BSC by using Kaplan-Meier analysis. Results: Of 29 patients in each study arm, 16 pairs (55.2%) matched for all four criteria, and 11 pairs (37.9%) matched three criteria. Patients in both groups had a similar performance status (Karnofsky index, median 80% [range, 60-100%]). Compared with BSC alone, radioembolization prolonged survival (median, 8.3 vs. 3.5 months; P < 0.001) with a hazard ratio of 0.3 (95% confidence interval, 0.16-0.55; P < 0.001) in a multivariate Cox proportional hazard model. Treatment-related adverse events following radioembolization included: grade 1-2 fatigue (n = 20, 69%), grade 1 abdominal pain/nausea (n = 14, 48.3%), and grade 2 gastrointestinal ulceration (n = 3, 10.3%). Three cases of grade 3 radiation-induced liver disease were symptomatically managed. Conclusions: Radioembolization offers a promising addition to BSC in treatment-refractory patients for whom there are limited options. Survival was prolonged and adverse events were generally mild-to-moderate in nature and manageable.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2015

Synthesis of carbon supported ordered tetragonal pseudo-ternary Pt 2 M'M'' (M = Fe, Co, Ni) nanoparticles and their activity for oxygen reduction reaction

Alloying Pt with 3d transition metals has attracted much attention due to their reduced Pt content and reports of enhanced electrocatalytic activity for proton exchange membrane fuel cell applications. However, synthesizing ordered nanocrystalline intermetallics in the sub-10 nm range can be challenging. Here, we report on the co-reduction synthesis of ordered ternary Pt-base transition metal intermetallics with particle sizes in the regime of 3–5 nm. Since differences in the activity of PtM (M = Fe, Co, Ni) for oxygen reduction reaction (ORR) have been reported, we explored their combinations: Pt 2 FeCo, Pt 2 FeNi, and Pt 2 CoNi. These ternary intermetallic nanoparticles crystallized in P4/mmm space group upon annealing in a protective KCl matrix. The electrocatalysts were prepared by dispersing these intermetallics onto a carbon support using ethylene glycol and various sonication techniques. A combination of analytical techniques including powder X-ray diffraction, thermogravimetric analysis, electron microscopy and electrochemical methods have been used in this study. The oxygen reduction reaction activity and stability of the catalysts were tested in 0.1 M HClO 4 and 0.1 M H 2 SO 4 using cyclic voltammetry and rotating disk electrode voltammetry. The correlations between the composition, structure, morphology and activity of the intermetallics have been established and are discussed.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗