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Results for “CARBONYLS”

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 469 records · Page 26
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

XPS and STEM Study of the Interface Formation between Ultra-Thin Ru and Ir OER Catalyst Layers and Perylene Red Support Whiskers

The interface formation between perylene red (PR) and ruthenium or iridium OER catalysts has been studied systematically by XPS and STEM. The OER catalyst over-layers with thicknesses ranging from ~0.1 to ~50 nm were vapor deposited onto PR ex-situ. As seen by STEM, Ru and Ir form into nanoparticles, which agglomerate with increased loading. XPS data show a strong interaction between Ru and PR. Ir also interacts with PR although not to the extent seen for Ru. At low coverages, the entire Ru deposit is in the reacted state while a small portion of the deposited Ir remains metallic. Ru and Ir bonding occur at the PR carbonyl sites as evidenced by the attenuation of carbonyl photoemission and the emergence of new peak assigned to C-O single bond. The curve fitting analysis and the derived stoichiometry indicates the formation of metallo-organic bonds. The co-existence of oxide bonds is also apparent.

Atanasoska, Liliana↗
DOE OSTI2016

Cage-like bifunctional chelators, copper-64 radiopharmaceuticals and PET imaging using the same

Disclosed is a class of versatile Sarcophagine based bifunctional chelators (BFCs) containing a hexa-aza cage for labeling with metals having either imaging, therapeutic or contrast applications radiolabeling and one or more linkers (A) and (B). The compounds have the general formula ##STR00001## where A is a functional group selected from group consisting of an amine, a carboxylic acid, an ester, a carbonyl, a thiol, an azide and an alkene, and B is a functional group selected from the group consisting of hydrogen, an amine, a carboxylic acid, and ester, a carbonyl, a thiol, an azide and an alkene. Also disclosed are conjugate of the BFC and a targeting moiety, which may be a peptide or antibody. Also disclosed are metal complexes of the BFC/targeting moiety conjugates that are useful as radiopharmaceuticals, imaging agents or contrast agents.

62 RADIOLOGY AND NUCLEAR MEDICINE↗
DOE OSTI2017

High efficiency iron electrode and additives for use in rechargeable iron-based batteries

An iron electrode and a method of manufacturing an iron electrode for use in an iron-based rechargeable battery are disclosed. In one embodiment, the iron electrode includes carbonyl iron powder and one of a metal sulfide additive or metal oxide additive selected from the group of metals consisting of bismuth, lead, mercury, indium, gallium, and tin for suppressing hydrogen evolution at the iron electrode during charging of the iron-based rechargeable battery. An iron-air rechargeable battery including an iron electrode comprising carbonyl iron is also disclosed, as is an iron-air battery wherein at least one of the iron electrode and the electrolyte includes an organosulfur additive.

25 ENERGY STORAGE↗
DOE OSTI2019

Conversion of acetone and/or alcohol(s) to alcohol(s) and/or aliphatic hydrocarbons

A process for the production of saturated or unsaturated aliphatic alcohols and/or hydrocarbons includes condensing acetone and/or alcohol(s) to form one or more carbonyl compounds, and hydrogenating and/or hydrodeoxygenating at least one of the one or more carbonyl compounds to form the saturated or unsaturated alcohol(s) and/or hydrocarbons. In some embodiments, the condensation of acetone and/or alcohol(s) may be carried out in the presence of a solid acid catalyst and a transition metal catalyst. The saturated or unsaturated aliphatic alcohols and/or hydrocarbons may include one or more saturated linear C9 alcohols, C9 alkanes and/or one or more mono-unsaturated C9 alkenes.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

High efficiency iron electrode and additives for use in rechargeable iron-based batteries

An iron electrode and a method of manufacturing an iron electrode for use in an iron-based rechargeable battery are disclosed. In one embodiment, the iron electrode includes carbonyl iron powder and one of a metal sulfide additive or metal oxide additive selected from the group of metals consisting of bismuth, lead, mercury, indium, gallium, and tin for suppressing hydrogen evolution at the iron electrode during charging of the iron-based rechargeable battery. An iron-air rechargeable battery including an iron electrode comprising carbonyl iron is also disclosed, as is an iron-air battery wherein at least one of the iron electrode and the electrolyte includes an organosulfur additive.

25 ENERGY STORAGE↗
DOE OSTI2021

Continuous method for preparing carbonate esters

In one embodiment, a continuous process for preparing organic carbonate solvent of Formula (I) as described herein comprises contacting a first reactant (an alcohol) with a reactive carbonyl source (carbonyldiimidazole (CDI) or an alkylchloroformate) in the presence of a catalyst in reaction stream flowing through a continuous flow reactor at temperature 20° C. to about 160° C. and at a flow rate providing a residence time in the range of about 0.1 minute to about 24 hours; collecting a reactor effluent exiting from the continuous flow reactor; recovering a crude product from the reactor effluent; and distilling the crude product to obtain the organic carbonate compound of Formula (I). In another embodiment, the first reactant is an epoxide and the carbonyl source is carbon dioxide.

Dzwiniel, Trevor L.↗
DOE OSTI2022

Standard Analytical Methods for Pyrolysis Bio-Oils

There has been significant recent interest in the production of renewable fuels and chemicals from biomass and waste feedstocks. Pyrolysis pathways produce a liquid bio-oil product, which must be processed further, or upgraded, to yield fuel or chemical products. Bio-oils are very complex and often unstable samples, and research and development on upgrading processes needs reliable analytical information. In particular, chemical characterization techniques are needed to quantify both functional groups and individual compounds present in bio-oils. Reliable analytics are also needed to enable the bioenergy industry, as industrial facilities often have different analytical needs and capabilities than research facilities. In this presentation, we will discuss the development of a suite of standard analytical methods for pyrolysis bio-oils. Analytical methods to be discussed include: Determination of Carbon, Hydrogen, Nitrogen, and Oxygen in bio-oils; Accelerated Aging of Fast Pyrolysis Bio-oil using Carbonyl Titration; Determination of Water Content in Bio-oils by Volumetric Karl Fischer Titration; Determination of Carbon Functional Groups; Elemental Analysis of Bio-oils by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES) - Na, K, Mg, Ca, S, P, and Fe; Determination of Phenolic Groups in Bio-oils using Revised Folin-Ciocalteu Methods: Single Cuvette and Plate Reader; Corrosivity of Bio-oils: Screening Test using Metal Leaching; Determination of Biogenic Content by 14C Measurement using Liquid Scintillation Counter. These new analytical methods are publicly available as Laboratory Analytical Procedures (https://www.nrel.gov/bioenergy/bio-oil-analysis.html), along with previously developed standard methods: GC-MS, Acid Titration, Carbonyl Titration, and 31P NMR. Additionally, the development of diffusion ordered NMR for characterization of bio-oil molecular weight will be discussed. Collectively, this suite of analytical methods represents the most comprehensive set of standard methods available for pyrolysis bio-oils. These standard methods are commonly used by the bioenergy community, and provide reliable information that enables research, scaleup, and industrial processing of biomass to produce renewable fuels and chemicals.

analytical↗
DOE OSTI2023

Continuous method for preparing carbonate esters

In one embodiment, a continuous process for preparing organic carbonate solvent of Formula (I) as described herein comprises contacting a first reactant (an alcohol) with a reactive carbonyl source (carbonyldiimidazole (CDI) or an alkylchloroformate) in the presence of a catalyst in reaction stream flowing through a continuous flow reactor at temperature 20° C. to about 160° C. and at a flow rate providing a residence time in the range of about 0.1 minute to about 24 hours; collecting a reactor effluent exiting from the continuous flow reactor; recovering a crude product from the reactor effluent; and distilling the crude product to obtain the organic carbonate compound of Formula (I). In another embodiment, the first reactant is an epoxide and the carbonyl source is carbon dioxide.

Dzwiniel, Trevor L.↗
DOE OSTI2016

Single-Site Osmium Catalysts on MgO: Reactivity and Catalysis of CO Oxidation

MgO-supported osmium dioxo species, described as Os(=O) 2 {-Osupport} 1 or 2 (the brackets denote O atoms of the MgO surface), formed from Os 3 (CO) 12 via supported Os(CO) 2 , and characterized by spectroscopy, microscopy, and theory, react with ethylene at 298 K to form osmium glycol species or with CO to give osmium mono- and di-carbonyls. Os(=O) 2 {-Osupport} 1 or 2 is the precursor of a CO oxidation catalyst characterized by a turnover frequency of 4.0×10 -3 (molecules of CO)/(Os atom×s) at 473 K; the active species are inferred to be osmium monocarbonyls. The structures and frequencies calculated at the level of density functional theory with the B3LYP functional bolster the experimental results and facilitate structural assignments. The lowest-energy structures have various osmium oxidation and spin states. The results demonstrate not only new chemistry of the supported single-site catalysts but also their complexity and the value of complementary techniques used in concert to unravel the chemistry.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Structure-activity relationship for vanilloid compounds from extract of Zingiber officinale var rubrum rhizomes: effect on extracellular melanogenesis inhibitory activity

The components in the methanol extract of Zingiber officinale var rubrum (red ginger) were isolated by a series of column chromatography and identified by Nuclear Magnetic Resonance (NMR) and Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOFMS). Thirteen components, including eleven vanilloid compounds, were isolated from the extract. All the isolated components reduced extracellular melanin contents. Structure-activity relationship studies suggested that elongation of the carbon chain of shogaol and gingerol increased the extracellular melanogenesis inhibitory activity, and that the carbonyl and hydroxyl groups on the carbon chain in gingerol played an important role in this effect. In order to reveal the importance of the vanillyl group for the melanogenesis inhibitory activity, 6-gingerol (1) and 6-shogaol (5), which were the main compounds in the extract, were glucosylated and their effects were evaluated. The glucosylated 6-shogaol resulted in improved melanogenesis inhibitory activity, while the glucosylated 6-gingerol had no such effect. These results indicated different mechanisms for the melanogenesis inhibitory activity of the two vanilloid compounds.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2017

Enzyme-Assisted Extraction and Pb{sup 2+} Biosorption of Polysaccharide from Cordyceps militaris

The enzyme assisted extraction conditions of polysaccharide from Cordyceps militaris mycelia were firstly investigated by kinetics analysis and the optimal operating was found to be: extraction temperature 40 °C; solid-solvent ratio 1:20; extraction pH 4.0; cellulase concentration 2.0%. The polysaccharide extraction yield was 5.99% under these optimized conditions. Furthermore, a fundamental investigation of the biosorption of Pb{sup 2+} from aqueous solution by the C. militaris polysaccharide was performed under batch conditions. The suitable pH (5.0), polysaccharide concentration (0.20 g L{sup −1}), initial Pb{sup 2+} concentration (300 mg L{sup −1}) and contact time (40 min) were outlined to enhance Pb{sup 2+} biosorption from aqueous medium. The Langmuir isotherm model and pseudo first order kinetic model fitted well to the data of Pb{sup 2+} biosorption, suggesting the biosorption of Pb{sup 2+} onto C. militaris polysaccharide was monolayer biosorption and physical adsorption might be the rate-limiting step that controlled the adsorption process. FTIR analysis showed that the main functional groups of C. militaris polysaccharide involved in adsorption process were carbonyl, carboxyl, and hydroxyl groups.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Biodegradation in Soil of PLA/PBAT Blends Compatibilized with Chain Extender

This paper presents a study of biodegradation, in soil, of samples of poly(butylene adipate-co-terephthalate)(PBAT), poly(lactic acid) (PLA) and blends of these materials prepared in torque rheometer with the addition of a chain extender. Film samples of these materials were buried in soil under controlled laboratory conditions. The degraded samples were regularly taken from soil and analyzed by visual inspection, size exclusion chromatography, differential scanning calorimetry and infrared spectroscopy. Respirometry biodegradation tests were conducted to assess samples mineralization degree. Blends showed higher degree of crystallinity compared to pure polymers. Crystallinity degree enhanced during the biodegradation process in all samples, being able to causing the samples to degrade slowly. The study showed the great complexity of the biodegradation process of PLA and PBAT blends when compatibilized with a chain extender. The biodegradation rate showed different results depending on the characteristic applied to evaluate it: visual, molecular weight or mineralization. The chain extender had strong influence in PBAT and blends degradation, slowing the process as observed by the variation of molecular weight and carbonyl index. Blends showed an intermediate behavior compared to the original polymers.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2018

Degradability Characterization of EPDM/IIR Blends by γ-irradiation

In this paper the modifications induced in butyl rubbers (pristine, chlorinated and brominated sorts) by γ-irradiation are investigated by swelling, chemiluminescence and FT-IR. The susceptibility of butyl rubbers for the generation of radicals orders their stabilities in the following sequence: IIR > IIR—Cl > IIR—Br. The incorporation of butyl rubbers into ethylene-propylene terpolymer matrix brings about increased densities of radicals initiating modifications in the oxidation state in respect with recombination, which are intensified as the processing dose increases. Based on the variation of carbonyl and hydroxyl indices the favorable route for the recycling EPDM based formulations would be suggested in this study. The chemiluminescence spectra proving the formation of peroxyl radicals at about 100 °C prove their availability as reclaiming solutions. IIR—Br is the recommendable butyl rubber for the recovery procedure by association with EPDM. The suitability of IIRs for recycling purposes is analyzed by the variation in their crosslink densities, free volumes and swelling degrees. The crosslinking behavior of stabilized EPDM/IIR blends that runs to the improvement of durability is depicted by Charlesby–Pinner representation, which involves the different simultaneous contribution of scission and crosslinking processes.

36 MATERIALS SCIENCE↗
DOE OSTI2018

Glutaraldehyde as Ambient Temperature Crosslinking Agent of Latex Films from Natural Rubber Grafted with Poly(diacetone acrylamide)

The concept of using glutaraldehyde (GTA) to crosslink natural rubber (NR) particles bearing diacetone acrylamide (DAAM) functional groups during film formation was investigated in the present work. The primary advantage of this curing system is that it is feasible under ambient conditions, which can lower operating costs of the curing process. Graft copolymers of NR and poly(diacetone acrylamide) prepared with 5 wt% of DAAM (NR–g–PDAAM5) were synthesized by seeded emulsion polymerization at 50 °C. Then, the tensile properties were measured for cast films formed from NR–g–PDAAM5 latex in the absence and presence of GTA. The results revealed increased tensile strength of the NR–g–PDAAM5 film, when GTA was added into the latex prior to film casting. The crosslinking of NR–g–PDAAM5 latex film by reaction with GTA, after film casting, was also investigated using attenuated total reflection Fourier transform infrared (ATR–FTIR) and dynamic mechanical thermal analysis (DMTA). ATR–FTIR analysis demonstrated that crosslinking reactions formed conjugated C=C double bonds between the active carbonyl groups of DAAM and GTA. The complementary use of DMTA also corroborated that crosslinking reactions took place involving the grafted PDAAM chains on the NR particles. This was evidenced by a clear shift towards higher temperatures of the tan δ peak, corresponding to the T{sub g} of NR–g–PDAAM phase, when GTA was incorporated into the NR–g–PDAAM5 latex before film formation. Additionally, a noticeable increase in thermal stability of the NR–g–PDAAM5 film was also observed with added GTA. Hence, it can be concluded that GTA is an efficient room-temperature crosslinker for NR particles functionalized with DAAM. This curing system can also be considered an alternative, simple, and inexpensive method for curing NR latex compounds, as only one component (GTA) is required in the curing process.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Disintegration and Biodegradation in Soil of PBAT Mulch Films: Influence of the Stabilization Systems Based on Carbon Black/Hindered Amine Light Stabilizer and Carbon Black/Vitamin E

This work characterized the disintegration and biodegradation of aged samples of PBAT films with and without photostabilization additives. The objective is to correlate these processes with properties affected after aging, i.e. molecular weight and gel content. Three different formulations were studied: pure polymer; PBAT with carbon black and hindered amine light stabilizer (HALS) and PBAT with carbon black and phenolic stabilizer vitamin E. The samples were monitored for 12 months. As expected, the lower level of photostabilization lead to the higher disintegration and biodegradation rates. Nevertheless, mineralization test showed that during time the differences among biodegradation rates become subtler. The crystallinity degree presented changes only at an advanced stage of degradation process, showing a reduction. The evaluation of the carbonyl index, molecular weight, surface morphology and visual analysis allowed to observe that the aged samples with lower gel content and lower molecular weight showed a faster degradation rate. The changes in material structure due to the increase of aromatic units concentration is the main hypothesis to explain the material behavior during degradation in soil.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2019

Investigation of Photodegradation Preventing of Polyvinyl Alcohol/Nanoclay Composites

The effects of UV irradiation on chemical, thermal, mechanical, and morphological properties of polyvinyl alcohol (PVOH)/2 wt.% of nanoclay(NC) filler were investigated. PVOH composite films were prepared from PVOH blend with fixed content (2%) of NC via the solution casting method. Pure PVOH and PVOH composites were exposed to 340 nm fluorescent UV lamps and assessed for 50 h, 100 h, and 200 h UV exposue. The experimental results such as Fourier transform infrared (FTIR) confirmed that 2% wt. NC filler is efficient and can resist chemical degradation that is caused by ultraviolet irradiation (UV). The carbonyl and hydroxyl indices were increased with increasing the UV exposure irradiation times of both PVOH and PVOH composite. However, the PVOH nanocomposites exhibited more resistant to increasing the indices after exposure to UV irradiation with a longer exposure time. The thermal results (TGA) indicated that PVOH nanocomposite is exhibited more resistance to thermal degradation after UV irradiation exposure compared to that of pure PVOH sample. From DMA results, the storage of modulus was reduced after exposure to UV irradiation of PVOH and PVOH nanocomposites. The results of T{sub g} of PVOH nanocomposites increased after the incorporation of 2% wt. NC into PVOH after exposure to UV irradiation. PVOH nanocomposite exhibited more resistance to reduce the tensile strength after exposure to 200 h UV irradiation. XRD tests showed that PVOH/2 wt.% NC nanocomposites have more resistant to increase intensity after exposure to 200 h UV irradiation compared to that of PVOH sample. The morphology micrographs showed that no obvious cracks on the PVOH nanocomposite after UV irradiation exposure by comparing to that of pure PVOH.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Effects of Surface Modifications of Kraft Wood Pulp Cellulose Fibres on Improving the Mechanical Properties of Cellulose Fibre/Latex Composites

In this work, three composites with different contents (5, 10, and 15% w/w) of kraft pulp fibre were produced as reinforcing elements for natural latex matrix and the mechanical properties were evaluated. In order to improve the interfacial adhesion between the matrix and the reinforcing element, chemical modifications were carried out on the surface of the fibres using octanoyl and benzoyl chlorides as modifying agents. The extension of chemical modification of the fibres was visualized by the presence of absorption bands in the spectroscopy analyzes of the modified fibre in relation to the crude fibre (ester carbonyl 1700–1740 cm{sup −1}); in addition, the hydroxyl band was preserved, which indicates a modification of surface character. The modified fibres became more hydrophobic due to the decrease in surface energy and the change in the dispersive and polar components. An increase in the storage modulus was observed for the composites with surface-modified fibres, which agrees with the improved dispersion between the surface-modified fibres and the matrix verified by means of scanning electron microscopy images. The incorporation of fibres did not cause changes in the thermal properties of the composites.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Properties and Biodegradation of Thermoplastic Starch Obtained from Grafted Starches with Poly(lactic acid)

Properties and biodegradation of thermoplastic starch obtained using granular starches grafted with poly(lactic acid) (St-g-PLA) were studied. The grafting of PLA on the starch granule was verified by the emergence of the carbonyl group in the FTIR spectra and the higher diameter of the grafted starch granule. Thermoplastic starch from ungrafted granular starch (TPS) and grafted granular starch (TPGS) were obtained by mixing ungrafted or grafted starch with water, glycerol or sorbitol in a mixer. TPS and TPGS behave as plastic materials, and their mechanical properties depend on the type of plasticizer used. Materials with glycerol as the plasticizer exhibited less rigidity than the materials obtained using sorbitol. The presence of starch-g-PLA results in an increase in the elongation of the thermoplastic material. TPS and TPGS were hydrolysed by amylolytic enzymes in short-time periods compared to granular PLA-grafted starches.

36 MATERIALS SCIENCE↗