WorldWideScience

Sample records for americium additions

  1. Chemistry of americium

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, W.W.

    1976-01-01

    Essential features of the descriptive chemistry of americium are reviewed. Chapter titles are: discovery, atomic and nuclear properties, collateral reading, production and uses, chemistry in aqueous solution, metal, alloys, and compounds, and, recovery, separation, purification. Author and subject indexes are included. (JCB)

  2. The Biokinetic Model of Americium

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    To improve in vivo measurements for detecting internal exposure from transuranium radio nuclides, such as neptunium, plutonium, americium, the bioknetic model was studied. According to ICRP report (1993, 1995, 1997) and other research, the

  3. Reduction Rates for Higher Americium Oxidation States in Nitric Acid

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, Travis Shane [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mincher, Bruce Jay [Idaho National Lab. (INL), Idaho Falls, ID (United States); Schmitt, Nicholas C [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-30

    The stability of hexavalent americium was measured using multiple americium concentrations and nitric acid concentrations after contact with the strong oxidant sodium bismuthate. Contrary to our hypotheses Am(VI) was not reduced faster at higher americium concentrations, and the reduction was only zero-order at short time scales. Attempts to model the reduction kinetics using zero order kinetic models showed Am(VI) reduction in nitric acid is more complex than the autoreduction processes reported by others in perchloric acid. The classical zero-order reduction of Am(VI) was found here only for short times on the order of a few hours. We did show that the rate of Am(V) production was less than the rate of Am(VI) reduction, indicating that some Am(VI) undergoes two electron-reduction to Am(IV). We also monitored the Am(VI) reduction in contact with the organic diluent dodecane. A direct comparison of these results with those in the absence of the organic diluent showed the reduction rates for Am(VI) were not statistically different for both systems. Additional americium oxidations conducted in the presence of Ce(IV)/Ce(III) ions showed that Am(VI) is reduced without the typical growth of Am(V) observed in the systems sans Ce ion. This was an interesting result which suggests a potential new reduction/oxidation pathway for Am in the presence of Ce; however, these results were very preliminary, and will require additional experiments to understand the mechanism by which this occurs. Overall, these studies have shown that hexavalent americium is fundamentally stable enough in nitric acid to run a separations process. However, the complicated nature of the reduction pathways based on the system components is far from being rigorously understood.

  4. Isotopic and elemental composition of plutonium/americium oxides influence pulmonary and extra-pulmonary distribution after inhalation in rats.

    Science.gov (United States)

    Van der Meeren, A; Grémy, O

    2010-09-01

    The biodistribution of plutonium and americium has been studied in a rat model after inhalation of two PuO(2) powders in lungs and extra-pulmonary organs from 3 d to 3 mo. The main difference between the two powders was the content of americium (approximately 46% and 4.5% of total alpha activity). The PuO(2) with a higher proportion of americium shows an accelerated transfer of activity from lungs to blood as compared to PuO(2) with the lower americium content, illustrated by increased urinary excretion and higher bone and liver actinide retention. The total alpha activity measured reflects mostly the americium biological behavior. The activity contained in epithelial lining fluid, recovered in the acellular phase of broncho-alveolar lavages, mainly contains americium, whereas plutonium remains trapped in macrophages. Epithelial lining fluid could represent a transitional pulmonary compartment prior to translocation of actinides to the blood and subsequent deposition in extra-pulmonary retention organs. In addition, differential behaviors of plutonium and americium are also observed between the PuO(2) powders with a higher dissolution rate for both plutonium and americium being obtained for the PuO(2) with the highest americium content. Our results indicate that the biological behavior of plutonium and americium after translocation into blood differ two-fold: (1) for the two actinides for the same PuO(2) aerosol, and (2) for the same actinide from the two different aerosols. These results highlight the importance of considering the specific behavior of each contaminant after accidental pulmonary intake when assessing extra-pulmonary deposits from the level of activity excreted in urine or for therapeutic strategy decisions.

  5. Aqueous Chloride Operations Overview: Plutonium and Americium Purification/Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Kimball, David Bryan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Skidmore, Bradley Evan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-06-22

    Acqueous Chloride mission is to recover plutonium and americium from pyrochemical residues (undesirable form for utilization and storage) and generate plutonium oxide and americium oxide. Plutonium oxide is recycled into Pu metal production flowsheet. It is suitable for storage. Americium oxide is a valuable product, sold through the DOE-OS isotope sales program.

  6. 5f-Electron Delocalization in Americium

    DEFF Research Database (Denmark)

    Skriver, Hans Lomholt; Andersen, O. K.; Johansson, B.

    1980-01-01

    The pressure-volume relation for americium has been obtained without adjustable parameters from self-consistent, spin-polarized band calculations. Around 100 kbar we find a first-order transition to a state with low volume and no spin. This is consistent with preliminary high-pressure measurements....

  7. The relative physiological and toxicological properties of americium and plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Carter, R.E.; Busch, E.; Johnson, O. [and others

    1951-11-15

    The relative physiological and toxicological properties of americium and plutonium have been studied following their intravenous administration to rats. The urinary and fecal excretion of americium was similar to that of plutonium administered as Pu(N0{sub 3}){sub 4}. The deposition of americium the tissues and organs of the rat was also similar to that observed for plutonium. The liver and the skeleton were the major sites of deposition. Zirconium citrate administered 15 minutes after injection of americium increased the urinary excretion of americium and decreased the amount found in the liver and the skeleton at 4 and 16 days. LD{sub 30}{sup 50} studies showed americium was slightly less toxic when given in the acute toxic range than was plutonium. The difference was, however, too slight to be important in establishing a larger tolerance does for americium. Survival studies, hematological observations, bone marrow observations, comparison of tumor incidence and the incidence of skeletal abnormalities indicated that americium and plutonium have essentially the same chronic toxicity when given on an equal {mu}c. basis. These studies support the conclusion that the tolerance values for americium should be essentially the same as those for Plutonium.

  8. Surface complexation modeling of americium sorption onto volcanic tuff.

    Science.gov (United States)

    Ding, M; Kelkar, S; Meijer, A

    2014-10-01

    Results of a surface complexation model (SCM) for americium sorption on volcanic rocks (devitrified and zeolitic tuff) are presented. The model was developed using PHREEQC and based on laboratory data for americium sorption on quartz. Available data for sorption of americium on quartz as a function of pH in dilute groundwater can be modeled with two surface reactions involving an americium sulfate and an americium carbonate complex. It was assumed in applying the model to volcanic rocks from Yucca Mountain, that the surface properties of volcanic rocks can be represented by a quartz surface. Using groundwaters compositionally representative of Yucca Mountain, americium sorption distribution coefficient (Kd, L/Kg) values were calculated as function of pH. These Kd values are close to the experimentally determined Kd values for americium sorption on volcanic rocks, decreasing with increasing pH in the pH range from 7 to 9. The surface complexation constants, derived in this study, allow prediction of sorption of americium in a natural complex system, taking into account the inherent uncertainty associated with geochemical conditions that occur along transport pathways.

  9. Self-irradiation and oxidation effects on americium sesquioxide and Raman spectroscopy studies of americium oxides

    Energy Technology Data Exchange (ETDEWEB)

    Horlait, Denis [CEA, DEN, DTEC/SDTC/LEMA, F-30207 Bagnols-sur-Cèze Cedex (France); Caraballo, Richard [CEA, DEN, DTCD/SECM/LMPA, F-30207 Bagnols-sur-Cèze Cedex (France); Lebreton, Florent [CEA, DEN, DTEC/SDTC/LEMA, F-30207 Bagnols-sur-Cèze Cedex (France); Jégou, Christophe [CEA, DEN, DTCD/SECM/LMPA, F-30207 Bagnols-sur-Cèze Cedex (France); Roussel, Pascal [Unité de Catalyse et Chimie du Solide, UMR 8012 CNRS, Ecole Nationale Supérieure de Chimie de Lille BP 90108, 59652 Villeneuve d’Ascq Cedex (France); Delahaye, Thibaud, E-mail: thibaud.delahaye@cea.fr [CEA, DEN, DTEC/SDTC/LEMA, F-30207 Bagnols-sur-Cèze Cedex (France)

    2014-09-15

    Americium oxides samples were characterized by X-ray diffraction (XRD) and Raman spectroscopy, with an emphasis on their structural behavior under oxidation and self-irradiation. Raman spectra of americium dioxide (AmO{sub 2}) and sesquioxide (Am{sub 2}O{sub 3}) were obtained for the first time. With the help of literature data on isostructural oxides, Raman signatures of Ia-3 C-type Am{sub 2}O{sub 3} and P-3m1 A-type Am{sub 2}O{sub 3} are identified. For AmO{sub 2,} a clear band is noted at 390 cm{sup −1}. Its nature is compared to that of the other actinide dioxides. Am{sub 2}O{sub 3} evolution under ambient conditions and against {sup 241}Am α self-irradiation was monitored by powder XRD. The sample, initially composed of A-type Am{sub 2}O{sub 3} as major phase as well as C2/m B-type and C-type structures as minor phases, progressively oxidizes to Fm-3m AmO{sub 2−δ} over a few months. On the basis of diffractogram refinements, evolutions of unit cell volumes caused by self-irradiation are also determined and discussed. - Graphical abstract: The evolution of americium oxide under ambient conditions was monitored using XRD (X-ray diffraction) and Raman spectroscopy. After a thermal treatment under reducing conditions, a polyphasic sample mainly composed of A- and C-type americium sesquioxides is evidenced by XRD and Raman spectroscopy. The sample then evolves through two processes: oxidation and self-irradiation. The first one provokes the progressive appearance of F-type americium dioxide while the initial phases disappear, whereas the main effect of the second is a structural swelling with time. - Highlights: • The first Raman spectroscopy measurements on americium oxides were performed. • Observed Am{sub 2}O{sub 3} Raman bands were identified thanks to data on analogue compounds. • AmO{sub 2} assumed T{sub 2g} band presents a shift compared to the actinide dioxide series. • Am{sub 2}O{sub 3} evolution under self-irradiation and oxidation was also

  10. Plutonium and Americium Geochemistry at Hanford: A Site Wide Review

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, Kirk J.; Felmy, Andrew R.

    2012-08-23

    This report was produced to provide a systematic review of the state-of-knowledge of plutonium and americium geochemistry at the Hanford Site. The report integrates existing knowledge of the subsurface migration behavior of plutonium and americium at the Hanford Site with available information in the scientific literature regarding the geochemistry of plutonium and americium in systems that are environmentally relevant to the Hanford Site. As a part of the report, key research needs are identified and prioritized, with the ultimate goal of developing a science-based capability to quantitatively assess risk at sites contaminated with plutonium and americium at the Hanford Site and the impact of remediation technologies and closure strategies.

  11. Americium/Curium Disposition Life Cycle Planning Study

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, W.N. [Westinghouse Savannah River Company, AIKEN, SC (United States); Krupa, J.; Stutts, P.; Nester, S.; Raimesch, R.

    1998-04-30

    At the request of the Department of Energy Savannah River Office (DOE- SR), Westinghouse Savannah River Company (WSRC) evaluated concepts to complete disposition of Americium and Curium (Am/Cm) bearing materials currently located at the Savannah River Site (SRS).

  12. Higher Americium Oxidation State Research Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Mincher, Bruce J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Law, Jack D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Goff, George S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Moyer, Bruce A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burns, Jon D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lumetta, Gregg J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sinkov, Sergey I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shehee, Thomas C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hobbs, David T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-12-18

    The partitioning of hexavalent Am from dissolved nuclear fuel requires the ability to efficiently oxidize Am(III) to Am(VI) and to maintain that oxidation state for a length of time sufficient to perform the separation. Several oxidants have been, or are being developed. Chemical oxidants include Ag-catalyzed ozone, Ag-catalyzed peroxydisulfate, Cu(III) periodate, and sodium bismuthate. Hexavalent americium has also now successfully been prepared by electrolysis, using functionalized electrodes. So-called auto-reduction rates of Am(VI) are sufficiently slow to allow for separations. However, for separations based on solvent extraction or ion exchange using organic resins, the high valence state must be maintained under the reducing conditions of the organic phase contact, and a holding oxidant is probably necessary. Until now, only Cu(III) periodate and sodium bismuthate oxidation have been successfully combined with solvent extraction separations. Bismuthate oxidation provided the higher DAm, since it acts as its own holding oxidant, and a successful hot test using centrifugal contactors was performed. For the other oxidants, Ag-catalyzed peroxydisulfate will not oxidize americium in nitric acid concentrations above 0.3 M, and it is not being further investigated. Peroxydisulfate in the absence of Ag catalysis is being used to prepare Am(V) in ion exchange work, discussed below. Preliminary work with Ag-catalyzed ozone has been unsuccessful for extractions of Am(VI) from 6.5 M HNO3, and only one attempt at extraction, also from 6.5 M HNO3, using the electrolytic oxidation has been attempted. However, this high acid concentration was based on the highest Am extraction efficiency using the bismuthate oxidant; which is only sparingly soluble, and thus the oxidation yield is based on bismuthate solubility. Lower acid concentrations may be sufficient with alternative oxidants and work with Ag-ozone, Cu(III) and electrolysis is on-going. Two non

  13. Aqueous Chloride Operations Overview: Plutonium and Americium Purification/Recovery

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, Kyle Shelton [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kimball, David Bryan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Skidmore, Bradley Evan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-28

    These are a set of slides intended for an information session as part of recruiting activities at Brigham Young University. It gives an overview of aqueous chloride operations, specifically on plutonium and americium purification/recovery. This presentation details the steps taken perform these processes, from plutonium size reduction, dissolution, solvent extraction, oxalate precipitation, to calcination. For americium recovery, it details the CLEAR (chloride extraction and actinide recovery) Line, oxalate precipitation and calcination.

  14. Pyrochemical investigations into recovering plutonium from americium extraction salt residues

    Energy Technology Data Exchange (ETDEWEB)

    Fife, K.W.; West, M.H.

    1987-05-01

    Progress into developing a pyrochemical technique for separating and recovering plutonium from spent americium extraction waste salts has concentrated on selective chemical reduction with lanthanum metal and calcium metal and on the solvent extraction of americium with calcium metal. Both techniques are effective for recovering plutonium from the waste salt, although neither appears suitable as a separation technique for recycling a plutonium stream back to mainline purification processes. 17 refs., 13 figs., 2 tabs.

  15. Electrodeposition of americium and physicochemical behaviour of the solution

    Energy Technology Data Exchange (ETDEWEB)

    Becerril-Vilchis, A. (Inst. Nacional de Investigaciones Nucleares, CMRI-LPR, Mexico City (Mexico)); Meas, Y. (CIDETEQ, Queretaro (Mexico)); Rojas-Hernandez, A. (Univ. Autonoma Metropolitana Iztapalapa, Area de Electroquimica, Mexico City (Mexico))

    1994-01-01

    A new method based on concepts of generalized species and equilibria, was applied to represent the thermodynamic distribution of americium species (including condensed phases) in an electrochemical system. Diagrams of the predominance-zone, Existence-predominance and Pourbaix-type for the americium/support electrolyte/water system were constructed. On the basis of these diagrams, the initial distribution of the species in the electrolyte and the deposition conditions were predicted when a current density was applied to a rotating disc electrode in steady-state. These results were related with the Hansen model for actinide electrodeposition. (orig.)

  16. Supercritical Fluid Extraction of Plutonium and Americium from Soil

    Energy Technology Data Exchange (ETDEWEB)

    Fox, R.V.; Mincher, B.J.

    2002-05-23

    Supercritical fluid extraction (SFE) of plutonium and americium from soil was successfully demonstrated using supercritical fluid carbon dioxide solvent augmented with organophosphorus and beta-diketone complexants. Spiked Idaho soils were chemically and radiologically characterized, then extracted with supercritical fluid carbon dioxide at 2,900 psi and 65 C containing varying concentrations of tributyl phosphate (TBP) and thenoyltrifluoroacetone (TTA). A single 45 minute SFE with 2.7 mol% TBP and 3.2 mol% TTA provided as much as 88% {+-} 6.0 extraction of americium and 69% {+-} 5.0 extraction of plutonium. Use of 5.3 mol% TBP with 6.8 mol% of the more acidic beta-diketone hexafluoroacetylacetone (HFA) provided 95% {+-} 3.0 extraction of americium and 83% {+-} 5.0 extraction of plutonium in a single 45 minute SFE at 3,750 psi and 95 C. Sequential chemical extraction techniques were used to chemically characterize soil partitioning of plutonium and americium in pre-SFE soil samples. Sequential chemical extraction techniques demonstrated that spiked plutonium resides primarily (76.6%) in the sesquioxide fraction with minor amounts being absorbed by the oxidizable fraction (10.6%) and residual fractions (12.8%). Post-SFE soils subjected to sequential chemical extraction characterization demonstrated that 97% of the oxidizable, 78% of the sesquioxide and 80% of the residual plutonium could be removed using SFE. These preliminary results show that SFE may be an effective solvent extraction technique for removal of actinide contaminants from soil.

  17. Thermodynamic systematics of oxides of americium, curium, and neighboring elements

    Energy Technology Data Exchange (ETDEWEB)

    Morss, L.R.

    1984-01-01

    Recently-obtained calorimetric data on the sesquioxides and dioxides of americium and curium are summarized. These data are combined with other properties of the actinide elements to elucidate the stability relationships among these oxides and to predict the behavior of neighboring actinide oxides. 45 references, 4 figures, 5 tables.

  18. Research program on development of advanced treatment technology for americium-containing aqueous waste in NUCEF

    Energy Technology Data Exchange (ETDEWEB)

    Mineo, Hideaki; Matsumura, Tatsuro; Tsubata, Yasuhiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-10-01

    A research program was prepared on the development of an advanced treatment process for the americium-containing concentrated aqueous waste in NUCEF, than allows americium recovery for the reuse and the reduction of TRU waste generation. A preliminary analysis was conducted on the separation requirements based on the components estimated for the waste. An R and D strategy was proposed from the view to reduce TRU waste generated in the processing that the highest priority is given on the control of TRU leakage such as americium into the effluent stream after americium recovery and the minimization of salt used in the separation over the decontamination of impurities from americium. The extraction chromatographic method was selected as a candidate technology for americium separation under the principle to use reagents that are functional in acidic conditions such as bidentate extractants of DHEDECMP, CMPO or diamides, considering the larger flexibilities in process modification and possible multi-component separation with compact equipment and the past achievements on the recovery of kg quantities of americium. Major R and D items extracted are screening and evaluation of extractants for americium and plutonium, optimization of separation conditions, selection of denitration method, equipment developments and development of solidification methods of discarded americium after reuse and of various kinds of separation residues. In order to cope these items, four steps of R and D program were proposed, i.e., fundamental experiment in beaker-scale on screening and evaluation of extractants, flowsheet study in bench-scale using simulated and small amount of americium aqueous waste solution to evaluate candidate process, americium recovery test in iron-shielded cell to be installed in NUCEF. It is objected to make recovery of 100g orders of americium used for research on fundamental TRU fuel properties. (J.P.N.)

  19. Supercritical Fluid Extraction of Plutonium and Americium from Soil

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Robert Vincent; Mincher, Bruce Jay

    2002-08-01

    Supercritical fluid extraction (SFE) of plutonium and americium from soil was successfully demonstrated using supercritical fluid carbon dioxide solvent augmented with organophosphorus and beta-diketone complexants. Spiked Idaho soils were chemically and radiologically characterized, then extracted with supercritical fluid carbon dioxide at 2,900 psi and 65°C containing varying concentrations of tributyl phosphate (TBP) and thenoyltrifluoroacetone (TTA). A single 45 minute SFE with 2.7 mol% TBP and 3.2 mol% TTA provided as much as 88% ± 6.0 extraction of americium and 69% ± 5.0 extraction of plutonium. Use of 5.3 mol% TBP with 6.8 mol% of the more acidic beta-diketone hexafluoroacetylacetone (HFA) provided 95% ± 3.0 extraction of americium and 83% ± 5.0 extraction of plutonium in a single 45 minute SFE at 3,750 psi and 95°C. Sequential chemical extraction techniques were used to chemically characterize soil partitioning of plutonium and americium in pre-SFE soil samples. Sequential chemical extraction techniques demonstrated that spiked plutonium resides primarily (76.6%) in the sesquioxide fraction with minor amounts being absorbed by the oxidizable fraction (10.6%) and residual fractions (12.8%). Post-SFE soils subjected to sequential chemical extraction characterization demonstrated that 97% of the oxidizable, 78% of the sesquioxide and 80% of the residual plutonium could be removed using SFE. These preliminary results show that SFE may be an effective solvent extraction technique for removal of actinide contaminants from soil.

  20. Isolation of americium (5) oxalate compounds from solutions

    Energy Technology Data Exchange (ETDEWEB)

    Zubarev, V.G.; Krot, N.N.

    1982-01-01

    Certain conditions of americium (5) isolation with solutions of ammonia and KOH are studied as well as the attitude of hydroxide obtained to heating. Like neptunium (5) hydroxide americium (5) hydroxide probably has the formula AmO/sub 2/OHxxH/sub 2/O, where x is approximately equal to 2.3. It is established that during heating in the air up to 120 deg C hydroxide transforms into AmO/sub 2/. It is shown that in solutions with a high concentration of oxalate-ion americium stability in oxidation state +5 depends greatly on the pH of solution. Complex salts KAmO/sub 2/C/sub 2/O/sub 4/xxH/sub 2/O and CsAmO/sub 2/C/sub 2/O/sub 4/xxH/sub 2/O are synthesized. The identification is made according to the method of preparation and results of analysis of C/sub 2/O/sub 4//sup 2 -/: AmO/sub 2//sup +/ ratio. It is found that the salts are non-isomorphous to similar salts of pentavalent neptunium. CsAmO/sub 2/C/sub 2/O/sub 4/xxH/sub 2/O is identified in cubic crystal system with the lattice constant a=1.25 nm.

  1. Separation of americium and curium from complex chemical and radiochemical mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Bochkarev, V.A.; Martynov, N.P.; Slivin, V.G.; Trikanov, A.E.; Fedyaeva, N.V.

    1988-11-01

    This work describes a method for separation and radiochemical purification of nanogram levels of americium and curium from complex chemical and radiochemical mixtures containing tens of milligrams of elements such as aluminum, iron, magnesium, calcium, barium, titanium, potassium, and others, microgram levels of uranium, neptunium, and plutonium, and fission products. Extraction coefficients of americium and curium from these elements are measured. The separation from the macrocomponents was carried out by extraction of americium and curium with butyric acid in the presence of sulfosalicylic acid. Uranium, neptunium, and plutonium were separated from hydrochloric acid solutions, while the rare earth elements were separated from lithium chloride solutions using a column of anion exchange resin AV-17. Alpha measurements were carried out on americium and curium deposited electrolytically on tantalum cathodes. The chemical yield of americium and curium was identical of greater than or equal to 94%, separation time approx. 8 h.

  2. Uncertainty analysis of doses from ingestion of plutonium and americium.

    Science.gov (United States)

    Puncher, M; Harrison, J D

    2012-02-01

    Uncertainty analyses have been performed on the biokinetic model for americium currently used by the International Commission on Radiological Protection (ICRP), and the model for plutonium recently derived by Leggett, considering acute intakes by ingestion by adult members of the public. The analyses calculated distributions of doses per unit intake. Those parameters having the greatest impact on prospective doses were identified by sensitivity analysis; the most important were the fraction absorbed from the alimentary tract, f(1), and rates of uptake from blood to bone surfaces. Probability distributions were selected based on the observed distribution of plutonium and americium in human subjects where possible; the distributions for f(1) reflected uncertainty on the average value of this parameter for non-specified plutonium and americium compounds ingested by adult members of the public. The calculated distributions of effective doses for ingested (239)Pu and (241)Am were well described by log-normal distributions, with doses varying by around a factor of 3 above and below the central values; the distributions contain the current ICRP Publication 67 dose coefficients for ingestion of (239)Pu and (241)Am by adult members of the public. Uncertainty on f(1) values had the greatest impact on doses, particularly effective dose. It is concluded that: (1) more precise data on f(1) values would have a greater effect in reducing uncertainties on doses from ingested (239)Pu and (241)Am, than reducing uncertainty on other model parameter values and (2) the results support the dose coefficients (Sv Bq(-1) intake) derived by ICRP for ingestion of (239)Pu and (241)Am by adult members of the public.

  3. Kilogram-scale purification of americium by ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Wheelwright, E. J.

    1979-01-01

    Sequential anion and cation exchange processes have been used for the final purification of /sup 241/Am recovered during the reprocessing of aged plutonium metallurgical scrap. Plutonium was removed by absorption of Dowex 1, X-3.5 (30 to 50 mesh) anion exchange resin from 6.5 to 7.5 M HNO/sub 3/ feed solution. Following a water dilution to 0.75 to 1.0 M HNO/sub 3/, americium was absorbed on Dowex 50W, X-8 (50 to 100 mesh) cation exchange resion. Final purification was accomplished by elution of the absorbed band down 3 to 4 successive beds of the same resin, preloaded with Zn/sup 2 +/, with an NH/sub 4/OH buffered chelating agent. The recovery of mixed /sup 241/Am-/sup 243/Am from power reactor reprocessing waste has been demonstrated. Solvent extraction was used to recover a HNO/sub 3/ solution of mixed lanthanides and actinides from waste generated by the reprocessng of 13.5 tons of Shippingport Power Reactor blanket fuel. Sequential cation exchange band-displacement processes were then used to separate americium and curium from the lanthanides and then to separate approx. 60 g of /sup 244/Cm from 1000 g of mixed /sup 241/Am-/sup 243/Am.

  4. Hexavalent Americium Recovery Using Copper(III) Periodate

    Energy Technology Data Exchange (ETDEWEB)

    McCann, Kevin; Brigham, Derek M.; Morrison, Samuel; Braley, Jenifer C.

    2016-11-21

    Separation of americium from the lanthanides is considered one of the most difficult separation steps in closing the nuclear fuel cycle. One approach to this separation could involve oxidizing americium to the hexavalent state to form a linear dioxo cation while the lanthanides remain as trivalent ions. This work considers aqueous soluble Cu3+ periodate as an oxidant under molar nitric acid conditions to separate hexavalent Am with diamyl amylphosphonate (DAAP) in n-dodecane. Initial studies assessed the kinetics of Cu3+ periodate auto-reduction in acidic media to aid in development of the solvent extraction system. Following characterization of the Cu3+ periodate oxidant, solvent extraction studies optimized the recovery of Am from varied nitric acid media and in the presence of other fission product, or fission product surrogate, species. Short aqueous/organic contact times encouraged successful recovery of Am (distribution values as high as 2) from nitric acid media in the absence of redox active fission products. In the presence of a post-PUREX simulant aqueous feed, precipitation of tetravalent species (Ce, Ru, Zr) occurred and the distribution values of 241Am were suppressed, suggesting some oxidizing capacity of the Cu3+ periodate is significantly consumed by other redox active metals in the simulant. The manuscript demonstrates Cu3+ periodate as a potentially viable oxidant for Am oxidation and recovery and notes the consumption of oxidizing capacity observed in the presence of the post-PUREX simulant feed will need to be addressed for any approach seeking to oxidize Am for separations relevant to the nuclear fuel cycle.

  5. Oxidative Alkaline leaching of Americium from simulated high-level nuclear waste sludges

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Wendy A.; Garnov, Alexander Yu.; Rao, Linfeng; Nash, Kenneth L.; Bond, Andrew H.

    2004-01-23

    Oxidative alkaline leaching has been proposed to pre-treat the high-level nuclear waste sludges to remove some of the problematic (e.g., Cr) and/or non-radioactive (e.g., Na, Al) constituents before vitrification. It is critical to understand the behavior of actinides, americium and plutonium in particular, in oxidative alkaline leaching. We have studied the leaching behavior of americium from four different sludge simulants (BiPO{sub 4}, BiPO{sub 4 modified}, Redox, PUREX) using potassium permanganate and potassium persulfate in alkaline solutions. Up to 60% of americium sorbed onto the simulants is leached from the sludges by alkaline persulfate and permanganate. The percentage of americium leached increases with [NaOH] (between 1.0 and 5.0 M). The initial rate of americium leaching by potassium persulfate increases in the order BiPO{sub 4} sludge < Redox sludge < PUREX sludge. The data are most consistent with oxidation of Am{sup 3+} in the sludge to either AmO{sub 2}{sup +} or AmO{sub 2}{sup 2+} in solution. Though neither of these species is expected to exhibit long-term stability in solution, the potential for mobilization of americium from sludge samples would have to be accommodated in the design of any oxidative leaching process for real sludge samples.

  6. Neutronic Study of Burnup, Radiotoxicity, Decay Heat and Basic Safety Parameters of Mono-Recycling of Americium in French Pressurised Water Reactors

    Directory of Open Access Journals (Sweden)

    Robert Bright Mawuko Sogbadji

    2017-03-01

    Full Text Available The reprocessing of actinides with long half-life has been non-existent except for plutonium (Pu. This work looks at reducing the actinides inventory nuclear fuel waste meant for permanent disposal. The uranium oxide fuel (UOX assembly, as in the open cycle system, was designed to reach a burnup of 46GWd/T and 68GWd/T using the MURE code. The MURE code is based on the coupling of a static Monte Carlo code and the calculation of the evolution of the fuel during irradiation and cooling periods. The MURE code has been used to address two different questions concerning the mono-recycling of americium (Am in present French pressurised water reactors (PWR. These are reduction of americium in the clear fuel cycle and the safe quantity of americium that can be introduced into mixed oxide (MOX as fuel. The spent UOX was reprocessed to fabricate MOX assemblies, by the extraction of plutonium and addition of depleted uranium to reach burnups of 46GWd/T and 68GWd/T, taking into account various cooling times of the spent UOX assembly in the repository. The effect of cooling time on burnup and radiotoxicity was then ascertained. After 30 years of cooling in the repository, the spent UOX fuel required a higher concentration of Pu to be reprocessed into MOX fuel due to the decay of Pu-241. Americium, with a mean half-life of 432 years, has a high radiotoxicity level, high mid-term residual heat and is a precursor for other long-lived isotopes. An innovative strategy would be to reprocess not only the plutonium from the UOX spent fuel but also the americium isotopes, which presently dominate the radiotoxicity of waste. The mono-recycling of Am is not a definitive solution because the once-through MOX cycle transmutation of Am in a PWR is not enough to destroy all americium. The main objective is to propose a ‘waiting strategy’ for both Am and Pu in the spent fuel so that they can be made available for further transmutation strategies. The MOX and

  7. The transmutation of americium: the Ecrix experiments in Phenix; Transmutation de l'americium: les experiences ecrix dans Phenix

    Energy Technology Data Exchange (ETDEWEB)

    Garnier, J.C.; Schmidt, N. [CEA Cadarache, Dept. d' Etudes des Combustibles (DEC/SESC), 13 - Saint-Paul-lez-Durance (France); Croixmarie, Y.; Ottaviani, J.P. [CEA Cadarache, Dept. d' Etudes des Combustibles (DEC/SPUA), 13 - Saint-Paul-lez-Durance (France); Varaine, F.; Saint Jean, C. de [CEA Cadarache, Dept. d' Etudes des Reacteurs (DER/SPRC), 13 - Saint-Paul-lez-Durance (France)

    1999-07-01

    The first americium transmutation experiment in a specific target in PHENIX will occur with the ECRIX-B and ECRIX-H experiments. Beside material testing, the objective is also to represent a concept of transmutation whose specificity is to enhance the kinetics of transmutation by using a moderated spectrum. The moderator materials will be {sup 11}B{sub 4}C and CaH{sub 2} for ECRIX-B and ECRIXH respectively, the irradiation conditions have been predicted for both the neutronics and thermal. The targets (MgO-AmO{sub X} pellets) are manufactured in the ATALANTE laboratory and the design is performed according to the PHENIX operating conditions. (authors)

  8. Effect of americium-241 on luminous bacteria. Role of peroxides

    Energy Technology Data Exchange (ETDEWEB)

    Alexandrova, M., E-mail: maka-alexandrova@rambler.r [Siberian Federal University, Svobodny 79, 660041 Krasnoyarsk (Russian Federation); Rozhko, T. [Siberian Federal University, Svobodny 79, 660041 Krasnoyarsk (Russian Federation); Vydryakova, G. [Institute of Biophysics SB RAS, Akademgorodok 50, 660036 Krasnoyarsk (Russian Federation); Kudryasheva, N. [Siberian Federal University, Svobodny 79, 660041 Krasnoyarsk (Russian Federation); Institute of Biophysics SB RAS, Akademgorodok 50, 660036 Krasnoyarsk (Russian Federation)

    2011-04-15

    The effect of americium-241 ({sup 241}Am), an alpha-emitting radionuclide of high specific activity, on luminous bacteria Photobacterium phosphoreum was studied. Traces of {sup 241}Am in nutrient media (0.16-6.67 kBq/L) suppressed the growth of bacteria, but enhanced luminescence intensity and quantum yield at room temperature. Lower temperature (4 {sup o}C) increased the time of bacterial luminescence and revealed a stage of bioluminescence inhibition after 150 h of bioluminescence registration start. The role of conditions of exposure the bacterial cells to the {sup 241}Am is discussed. The effect of {sup 241}Am on luminous bacteria was attributed to peroxide compounds generated in water solutions as secondary products of radioactive decay. Increase of peroxide concentration in {sup 241}Am solutions was demonstrated; and the similarity of {sup 241}Am and hydrogen peroxide effects on bacterial luminescence was revealed. The study provides a scientific basis for elaboration of bioluminescence-based assay to monitor radiotoxicity of alpha-emitting radionuclides in aquatic solutions. - Highlights: {yields} Am-241 in water solutions (A = 0.16-6.7 kBq/L) suppresses bacterial growth.{yields} Am-241 (A = 0.16-6.7 kBq/L) stimulate bacterial luminescence. {yields} Peroxides, secondary radiolysis products, cause increase of bacterial luminescence.

  9. Particulate distribution of plutonium and americium in surface waters from the Spanish Mediterranean coast

    Energy Technology Data Exchange (ETDEWEB)

    Molero, J.; Sanchez-Cabeza, J.A.; Merino, J.; Vidal-Quadras, A. [Universidad Autonoma de Barcelona (Spain); Vives Batlle, J.; Mitchell, P.I. [University Coll., Dublin (Ireland)

    1995-12-31

    Measurements of the particulate distribution of plutonium and americium in Spanish Mediterranean coastal waters have been carried out. Plutonium-239,340 and {sup 241}Am concentrations have been measured in suspended particulate matter by filtering (< 0.22 {mu}m) large volume (200-300 litres) sea water samples. Results indicate that particulate plutonium constitutes on average 11 {+-} 4% of the total concentration in sea water. In the case of americium this percentage rises to 45 {+-} 14%. From the {sup 241}Am/{sup 239,240}Pu activity ratios it is clear that suspended particulate matter is enriched in {sup 241}Am relative to {sup 239,240}Pu by a factor 8 {+-} 4. Plutonium and americium in surface Mediterranean coastal waters appear to be fractionated as they present a different transfer rate to the particles. Our measurements allowed us to estimate sediment-water distribution coefficients (K{sub d}), which are a key parameter to interpret differences between the behaviour of plutonium and americium in sea water. Distribution coefficients K{sub d} have been estimated to be (1.4 {+-} 0.5) x 10{sup 5} litres kg{sup -1} for plutonium and (0.9 {+-} 0.5) x 10{sup 6} litres kg{sup -1} for americium in surface Mediterranean coastal waters. (author).

  10. Development and Testing of an Americium/Lanthanide Separation Flowsheet Using Sodium Bismuthate

    Energy Technology Data Exchange (ETDEWEB)

    Jack Law; Bruce Mincher; Troy Garn; Mitchell Greenhalgh; Nicholas Schmitt; Veronica Rutledge

    2014-04-01

    The separation of Am from the lanthanides and curium is a key step in proposed advanced fuel cycle scenarios. The partitioning and transmutation of Am is desirable to minimize the long-term heat load of material interred in a future high-level waste repository. A separation process amenable to process scale-up remains elusive. Given only subtle chemistry differences within and between the ions of the trivalent actinide and lanthanide series this separation is challenging ; however, higher oxidation states of americium can be prepared using sodium bismuthate and separated via solvent extraction using diamylamylphosphonate (DAAP) extraction. Among the other trivalent metals only Ce is also oxidized and extracted. Due to the long-term instability of Am(VI) , the loaded organic phase is readily selectively stripped to partition the actinide to a new acidic aqueous phase. Batch extraction distribution ratio measurements were used to design a flowsheet to accomplish this separation. Additionally, crossflow filtration was investigated as a method to filter the bismuthate solids from the feed solution prior to extraction. Results of the filtration studies, flowsheet development work and flowsheet performance testing using a centrifugal contactor are detailed.

  11. National low-level waste management program radionuclide report series, Volume 14: Americium-241

    Energy Technology Data Exchange (ETDEWEB)

    Winberg, M.R.; Garcia, R.S.

    1995-09-01

    This report, Volume 14 of the National Low-Level Waste Management Program Radionuclide Report Series, discusses the radiological and chemical characteristics of americium-241 ({sup 241}Am). This report also includes discussions about waste types and forms in which {sup 241}Am can be found and {sup 241}Am behavior in the environment and in the human body.

  12. Understanding the Chemistry of Uncommon Americium Oxidation States for Application to Actinide/Lanthanide Separations

    Energy Technology Data Exchange (ETDEWEB)

    Leigh Martin; Bruce J. Mincher; Nicholas C. Schmitt

    2007-09-01

    A spectroscopic study of the stability of Am(V) and Am(VI) produced by oxidizing Am(III) with sodium bismuthate is presented, varying the initial americium concentration, temperature and length of the oxidation was seen to have profound effects on the resultant solutions.

  13. SKIN DOSIMETRY IN CONDITIONS OF ITS CONSTANT SURFACE CONTAMINATION WITH SOLUTIONS OF PLUTONIUM-239 AND AMERICIUM-241

    Directory of Open Access Journals (Sweden)

    E. B. Ershov

    2012-01-01

    Full Text Available The article considers, on the basis of experimental data, the issue of assessing dose burdens to the skin basal layer in conditions of its permanent contamination with solutions of plutonium-239 and americium-241 and subsequent decontamination.

  14. Influence of biofilms on migration of uranium, americium and europium in the environment; Einfluss von Biofilmen auf das Migrationsverhalten von Uran, Americium und Europium in der Umwelt

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Nils; Zirnstein, Isabel; Arnold, Thuro

    2015-07-01

    The report on the influence of biofilms on migration of uranium, americium and europium in the environment deals with the contamination problems of uranium mines such as SDAG WISMUT in Saxonia and Thuringia. In mine waters microorganisms form a complex microbiological biocoenosis in spite of low pH values and high heavy metal concentrations including high uranium concentrations. The analyses used microbiological methods like confocal laser scanning microscopy and molecular-biological techniques. The interactions of microorganism with fluorescent radioactive heavy metal ions were performed with TRLFS (time resolved laser-induced fluorescence spectroscopy).

  15. Standard test method for quantitative determination of americium 241 in plutonium by Gamma-Ray spectrometry

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1994-01-01

    1.1 This test method covers the quantitative determination of americium 241 by gamma-ray spectrometry in plutonium nitrate solution samples that do not contain significant amounts of radioactive fission products or other high specific activity gamma-ray emitters. 1.2 This test method can be used to determine the americium 241 in samples of plutonium metal, oxide and other solid forms, when the solid is appropriately sampled and dissolved. 1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  16. Calcium and zinc DTPA administration for internal contamination with plutonium-238 and americium-241.

    Science.gov (United States)

    Kazzi, Ziad N; Heyl, Alexander; Ruprecht, Johann

    2012-08-01

    The accidental or intentional release of plutonium or americium can cause acute and long term adverse health effects if they enter the human body by ingestion, inhalation, or injection. These effects can be prevented by rapid removal of these radionuclides by chelators such as calcium or zinc diethylenetriaminepentaacetate (calcium or zinc DTPA). These compounds have been shown to be efficacious in enhancing the elimination of members of the actinide family particularly plutonium and americium when administered intravenously or by nebulizer. The efficacy and adverse effects profile depend on several factors that include the route of internalization of the actinide, the type, and route time of administration of the chelator, and whether the calcium or zinc salt of DTPA is used. Current and future research efforts should be directed at overcoming limitations associated with the use of these complex drugs by using innovative methods that can enhance their structural and therapeutic properties.

  17. Final Radiological Assessment of External Exposure for CLEAR-Line Americium Recovery Operations

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Adam C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Belooussova, Olga N. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Hetrick, Lucas Duane [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-11-12

    Los Alamos National Laboratory is currently planning to implement an americium recovery program. The americium, ordinarily isotopically pure 241Am, would be extracted from existing Pu materials, converted to an oxide and shipped to support fabrication of americium oxide-beryllium neutron sources. These operations would occur in the currently proposed Chloride Extraction and Actinide Recovery (CLEAR) line of glove boxes. This glove box line would be collocated with the currently-operational Experimental Chloride Extraction Line (EXCEL). The focus of this document is to provide an in-depth assessment of the currently planned radiation protection measures and to determine whether or not further design work is required to satisfy design-goal and ALARA requirements. Further, this document presents a history of americium recovery operations in the Department of Energy and high-level descriptions of the CLEAR line operations to provide a basis of comparison. Under the working assumptions adopted by this study, it was found that the evaluated design appears to mitigate doses to a level that satisfies the ALARA-in-design requirements of 10 CFR 835 as implemented by the Los Alamos National Laboratory procedure P121. The analyses indicate that extremity doses would also meet design requirements. Dose-rate calculations were performed using the radiation transport code MCNP5 and doses were estimated using a time-motion study developed in consort with the subject matter expert. A copy of this report and all supporting documentation are located on the Radiological Engineering server at Y:\\Rad Engineering\\2013 PROJECTS\\TA-55 Clear Line.

  18. On the Convergence of the Electronic Structure Properties of the FCC Americium (001) Surface

    OpenAIRE

    Gao, Da; Ray, Asok K.

    2006-01-01

    Electronic and magnetic properties of the fcc Americium (001) surface have been investigated via full-potential all-electron density-functional electronic structure calculations at both scalar and fully relativistic levels. Effects of various theoretical approximations on the fcc Am (001) surface properties have been thoroughly examined. The ground state of fcc Am (001) surface is found to be anti-ferromagnetic with spin-orbit coupling included (AFM-SO). At the ground state, the magnetic mome...

  19. Intramolecular sensitization of americium luminescence in solution: shining light on short-lived forbidden 5f transitions.

    Science.gov (United States)

    Sturzbecher-Hoehne, M; Yang, P; D'Aléo, A; Abergel, R J

    2016-06-14

    The photophysical properties and solution thermodynamics of water soluble trivalent americium (Am(III)) complexes formed with multidentate chromophore-bearing ligands, 3,4,3-LI(1,2-HOPO), Enterobactin, and 5-LIO(Me-3,2-HOPO), were investigated. The three chelators were shown to act as antenna chromophores for Am(III), generating sensitized luminescence emission from the metal upon complexation, with very short lifetimes ranging from 33 to 42 ns and low luminescence quantum yields (10(-3) to 10(-2)%), characteristic of Near Infra-Red emitters in similar systems. The specific emission peak of Am(III) assigned to the (5)D1 → (7)F1 f-f transition was exploited to characterize the high proton-independent stability of the complex formed with the most efficient sensitizer 3,4,3-LI(1,2-HOPO), with a log β110 = 20.4 ± 0.2 value. In addition, the optical and solution thermodynamic features of these Am(III) complexes, combined with density functional theory calculations, were used to probe the influence of electronic structure on coordination properties across the f-element series and to gain insight into ligand field effects.

  20. MARIOS: Irradiation of UO{sub 2} containing 15% americium at well defined temperature

    Energy Technology Data Exchange (ETDEWEB)

    D' Agata, E., E-mail: elio.dagata@ec.europa.eu [European Commission, Joint Research Centre, Institute for Energy - P.O. Box 2, 1755 ZG Petten (Netherlands); Hania, P.R. [Nuclear Research and Consultancy Group, P.O. Box 25, 1755 ZG Petten (Netherlands); Bejaoui, S. [Commissariat a l' Energie Atomique, DEC CEA-Cadarache, 13108 St. Paul lez Durance Cedex (France); Sciolla, C.; Wyatt, T.; Hannink, M.H.C. [Nuclear Research and Consultancy Group, P.O. Box 25, 1755 ZG Petten (Netherlands); Herlet, N.; Jankowiak, A. [Commissariat a l' Energie Atomique DTEC CEA Marcoule, 30207 Bagnols sur Ceze Cedex (France); Klaassen, F.C. [Nuclear Research and Consultancy Group, P.O. Box 25, 1755 ZG Petten (Netherlands); Bonnerot, J.-M. [Commissariat a l' Energie Atomique, DEC CEA-Cadarache, 13108 St. Paul lez Durance Cedex (France)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer MARIOS is designed to check the behaviour of Minor Actinide Blanket Module concept. Black-Right-Pointing-Pointer Main requirement of the experiment is an accurate control of the temperature. Black-Right-Pointing-Pointer The swelling and the helium release will be the main output of the experiment. Black-Right-Pointing-Pointer A complementary experiment (DIAMINO), will be performed in the next future. - Abstract: Americium is a strong contributor to the long term radiotoxicity of high activity nuclear waste. Transmutation by irradiation in nuclear reactors of long-lived nuclides like {sup 241}Am is, therefore, an option for the reduction of radiotoxicity and residual power packages as well as the repository area. The MARIOS irradiation experiment is the latest of a series of experiments on americium transmutation (e.g. EFTTRA-T4, EFTTRA-T4bis, HELIOS). MARIOS experiment is carried out in the framework of the 4-year project FAIRFUELS of the EURATOM 7th Framework Programme (FP7). During the past years of experimental work in the field of transmutation and tests of innovative nuclear fuel containing americium, the release or trapping of helium as well as swelling has shown to be the key issue for the design of such kinds of target. Therefore, the main objective of the MARIOS experiment is to study the in-pile behaviour of UO{sub 2} containing minor actinides (MAs) in order to gain knowledge on the role of the microstructure and of the temperature on the gas release and on fuel swelling. The MARIOS experiment will be conducted in the HFR (high flux reactor) in Petten (The Netherlands) and will start in the beginning of 2011. It has been planned that the experiment will last 11 cycles, corresponding to 11 months. This paper covers the description of the objective of the experiment, as well as a general description of the design of the experiment.

  1. Speciation of americium in seawater and accumulation in the marine sponge Aplysina cavernicola.

    Science.gov (United States)

    Maloubier, Melody; Michel, Hervé; Solari, Pier Lorenzo; Moisy, Philippe; Tribalat, Marie-Aude; Oberhaensli, François R; Dechraoui Bottein, Marie Yasmine; Thomas, Olivier P; Monfort, Marguerite; Moulin, Christophe; Den Auwer, Christophe

    2015-12-21

    The fate of radionuclides in the environment is a cause of great concern for modern society, seen especially in 2011 after the Fukushima accident. Among the environmental compartments, seawater covers most of the earth's surface and may be directly or indirectly impacted. The interaction between radionuclides and the marine compartment is therefore essential for better understanding the transfer mechanisms from the hydrosphere to the biosphere. This information allows for the evaluation of the impact on humans via our interaction with the biotope that has been largely undocumented up to now. In this report, we attempt to make a link between the speciation of heavy elements in natural seawater and their uptake by a model marine organism. More specifically, because the interaction of actinides with marine invertebrates has been poorly studied, the accumulation in a representative member of the Mediterranean coralligenous habitat, the sponge Aplysina cavernicola, was investigated and its uptake curve exposed to a radiotracer (241)Am was estimated using a high-purity Ge gamma spectrometer. But in order to go beyond the phenomenological accumulation rate, the speciation of americium(III) in seawater must be assessed. The speciation of (241)Am (and natural europium as its chemically stable surrogate) in seawater was determined using a combination of different techniques: Time-Resolved Laser-Induced Fluorescence (TRLIF), Extended X-ray Absorption Fine Structure (EXAFS) at the LIII edge, Attenuated Total Reflectance Fourier Transform Infrared (ATR-FTIR) spectroscopy and Scanning Electron Microscopy (SEM) and the resulting data were compared with the speciation modeling. In seawater, the americium(III) complex (as well as the corresponding europium complex, although with conformational differences) was identified as a ternary sodium biscarbonato complex, whose formula can be tentatively written as NaAm(CO3)2·nH2O. It is therefore this chemical form of americium that is

  2. Plutonium and americium in arctic waters, the North Sea and Scottish and Irish coastal zones

    DEFF Research Database (Denmark)

    Hallstadius, L.; Aarkrog, Asker; Dahlgaard, Henning;

    1986-01-01

    collected from the Irish coast in 1983. Fallout is found to dominate as a source of 239+240Pu north of latitude 65°N, while for 238Pu a substantial fraction originates from European nuclear fuel reprocessing facilities. The 238Pu/239+240Pu isotope ratio provides clear evidence of the transport of effluent...... of the Irish Sea) to Spitsbergen. 241Am found in Arctic waters probably originates from the decay of fallout 241Pu and, like Pu, tentatively has a residence time of the order of several years. Americium from Sellafield has an estimated mean residence time of 4–6 months in Scottish waters....

  3. Penetration and decontamination of americium-241 ex vivo using fresh and frozen pig skin.

    Science.gov (United States)

    Tazrart, A; Bolzinger, M A; Moureau, A; Molina, T; Coudert, S; Angulo, J F; Briancon, S; Griffiths, N M

    2017-04-01

    Skin contamination is one of the most probable risks following major nuclear or radiological incidents. However, accidents involving skin contamination with radionuclides may occur in the nuclear industry, in research laboratories and in nuclear medicine departments. This work aims to measure the penetration of the radiological contaminant Americium ((241)Am) in fresh and frozen skin and to evaluate the distribution of the contamination in the skin. Decontamination tests were performed using water, Fuller's earth and diethylene triamine pentaacetic acid (DTPA), which is the recommended treatment in case of skin contamination with actinides such as plutonium or americium. To assess these parameters, we used the Franz cell diffusion system with full-thickness skin obtained from pigs' ears, representative of human skin. Solutions of (241)Am were deposited on the skin samples. The radioactivity content in each compartment and skin layers was measured after 24 h by liquid scintillation counting and alpha spectrophotometry. The Am cutaneous penetration to the receiver compartment is almost negligible in fresh and frozen skin. Multiple washings with water and DTPA recovered about 90% of the initial activity. The rest remains fixed mainly in the stratum corneum. Traces of activity were detected within the epidermis and dermis which is fixed and not accessible to the decontamination.

  4. Magnesium ionophore II as an extraction agent for trivalent europium and americium

    Energy Technology Data Exchange (ETDEWEB)

    Makrlik, Emanuel [Czech Univ. of Life Sciences, Prague (Czech Republic). Faculty of Environmental Sciences; Vanura, Petr [Univ. of Chemistry and Technology, Prague (Czech Republic). Dept. of Analytical Chemistry

    2016-11-01

    Solvent extraction of microamounts of trivalent europium and americium into nitrobenzene by using a mixture of hydrogen dicarbollylcobaltate (H{sup +}B{sup -}) and magnesium ionophore II (L) was studied. The equilibrium data were explained assuming that the species HL{sup +}, HL{sup +}{sub 2}, ML{sup 3+}{sub 2}, and ML{sup 3+}{sub 3} (M{sup 3+} = Eu{sup 3+}, Am{sup 3+}; L=magnesium, ionophore II) are extracted into the nitrobenzene phase. Extraction and stability constants of the cationic complex species in nitrobenzene saturated with water were determined and discussed. From the experimental results it is evident that this effective magnesium ionophore II receptor for the Eu{sup 3+} and Am{sup 3+} cations could be considered as a potential extraction agent for nuclear waste treatment.

  5. Imitators of plutonium and americium in a mixed uranium- plutonium nitride fuel

    Science.gov (United States)

    Nikitin, S. N.; Shornikov, D. P.; Tarasov, B. A.; Baranov, V. G.; Burlakova, M. A.

    2016-04-01

    Uranium nitride and mix uranium nitride (U-Pu)N is most popular nuclear fuel for Russian Fast Breeder Reactor. The works in hot cells associated with the radiation exposure of personnel and methodological difficulties. To know the main physical-chemical properties of uranium-plutonium nitride it necessary research to hot cells. In this paper, based on an assessment of physicochemical and thermodynamic properties of selected simulators Pu and Am. Analogues of Pu is are Ce and Y, and analogues Am - Dy. The technique of obtaining a model nitride fuel based on lanthanides nitrides and UN. Hydrogenation-dehydrogenation- nitration method of derived powders nitrides uranium, cerium, yttrium and dysprosium, held their mixing, pressing and sintering, the samples obtained model nitride fuel with plutonium and americium imitation. According to the results of structural studies have shown that all the samples are solid solution nitrides rare earth (REE) elements in UN.

  6. The Role of Colloids in the Transport of Plutonium and Americium: Implications for

    Energy Technology Data Exchange (ETDEWEB)

    Kersting, A B

    2003-09-17

    Colloids are small particulates (ranging in size from 1 to 0.001 micron) composed of inorganic and organic material and found in all natural water. Due to their small size, they have the ability to remain suspended in water and transported. Small amounts of plutonium (Pu) and americium (Am) can adsorb (attach) to colloids, and/or form colloidal-sized polymers and migrate in water. At Rocky Flats Environmental Technology Site (RFETS) sedimentation and resuspension of particulates and colloids in surface waters represent the dominant process for Pu and Am migration. The amount of Pu and Am that can be transported at RFETS has been quantified in the Pathway Analysis Report. The Pathway Analysis Report shows that the two dominant pathways for Pu and Am transport at RFETS are air and surface water. Shallow groundwater and biological pathways are minor.

  7. Standard practice for The separation of americium from plutonium by ion exchange

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2001-01-01

    1.1 This practice describes the use of an ion exchange technique to separate plutonium from solutions containing low concentrations of americium prior to measurement of the 241Am by gamma counting. 1.2 This practice covers the removal of plutonium, but not all the other radioactive isotopes that may interfere in the determination of 241Am. 1.3 This practice can be used when 241Am is to be determined in samples in which the plutonium is in the form of metal, oxide, or other solid provided that the solid is appropriately sampled and dissolved (See Test Methods C758, C759, and C1168). 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

  8. Separation of oxidized americium from lanthanides by use of pillared metal(IV) phosphate-phosphonate hybrid materials

    Energy Technology Data Exchange (ETDEWEB)

    Burns, J.D.; Clearfield, A. [Texas A and M Univ., College Station, TX (United States). Dept. of Chemistry; Borkowski, M.; Reed, D.T. [Los Alamos National Laboratory, Carlsbad, NM (United States). Earth and Environmental Sciences Div.

    2012-07-01

    Closing the nuclear fuel cycle in the US poses many challenges, one of which is found in the waste streams, which contain both trivalent lanthanides and actinides. The separation of americium from the raffinate will dramatically reduce the long-term radiotoxicity of the waste. The sorption of americium in both the tri- and pentavalent oxidation states was observed for four M(IV) phosphate-phosphonate ion exchange materials in nitric acid at pH 2. High selectivity was observed for reduced Am(III) with K{sub d} values ca. 6 x 10{sup 5} mL/g, while the K{sub d} values for Am(V) were much lower. A new method of synthesizing and stabilizing AmO{sub 2}{sup +} to yield a lifetime of at least 24 h in acidic media using a combination of sodium persulfate and calcium hypochlorite will be described.

  9. Theoretical investigation of pressure-induced structural transitions in americium using GGA+U and hybrid density functional theory methods

    DEFF Research Database (Denmark)

    Verma, Ashok K.; Modak, P.; Sharma, Surinder M.;

    2013-01-01

    First-principles calculations have been performed for americium (Am) metal using the generalized gradient approximation + orbital-dependent onsite Coulomb repulsion via Hubbard interaction (GGA+U) and hybrid density functional theory (HYB-DFT) methods to investigate various ground state properties...... spectrum at ambient pressure relate, for some parameter choices, well to peak positions in the calculated density of states function of Am-I....

  10. Vertical and horizontal fluxes of plutonium and americium in the western Mediterranean and the Strait of Gibraltar.

    Science.gov (United States)

    León Vintró, L; Mitchell, P I; Condren, O M; Downes, A B; Papucci, C; Delfanti, R

    1999-09-30

    New data on the vertical distributions of plutonium and americium in the waters of the western Mediterranean and the Strait of Gibraltar are examined in terms of the processes governing their delivery to, transport in and removal from the water column within the basin. Residence times for plutonium and americium in surface waters of approximately 15 and approximately 3 years, respectively, are deduced, and it is shown that by the mid 1990s only approximately 35% of the 239,240Pu and approximately 5% of the 241Am deposited as weapons fallout still resided in the water column. Present 239,240Pu inventories in the water column and the underlying sediments are estimated to be approximately 25 TBq and approximately 40 TBq, respectively, which reconcile well with the time-integrated fallout deposition in this zone, taken to be approximately 69 TBq. The data show that there are significant net outward fluxes of plutonium and americium from the basin through the Strait of Gibraltar at the present time. These appear to be compensated by net inward fluxes of similar magnitude through the Strait of Sicily. Thus, the time-integrated fallout deposition in the western basin can be accounted for satisfactorily in terms of present water column and sediment inventories. Enhanced scavenging on the continental shelves, as evidenced by the appreciably higher transuranic concentrations in shelf sediments, supports this contention.

  11. The behaviour under irradiation of molybdenum matrix for inert matrix fuel containing americium oxide (CerMet concept)

    Science.gov (United States)

    D'Agata, E.; Knol, S.; Fedorov, A. V.; Fernandez, A.; Somers, J.; Klaassen, F.

    2015-10-01

    Americium is a strong contributor to the long term radiotoxicity of high activity nuclear waste. Transmutation by irradiation in nuclear reactors or Accelerator Driven System (ADS, subcritical reactors dedicated to transmutation) of long-lived nuclides like 241Am is therefore an option for the reduction of radiotoxicity of waste packages to be stored in a repository. In order to safely burn americium in a fast reactor or ADS, it must be incorporated in a matrix that could be metallic (CerMet target) or ceramic (CerCer target). One of the most promising matrix to incorporate Am is molybdenum. In order to address the issues (swelling, stability under irradiation, gas retention and release) of using Mo as matrix to transmute Am, two irradiation experiments have been conducted recently at the High Flux Reactor (HFR) in Petten (The Netherland) namely HELIOS and BODEX. The BODEX experiment is a separate effect test, where the molybdenum behaviour is studied without the presence of fission products using 10B to "produce" helium, the HELIOS experiment included a more representative fuel target with the presence of Am and fission product. This paper covers the results of Post Irradiation Examination (PIE) of the two irradiation experiments mentioned above where molybdenum behaviour has been deeply investigated as possible matrix to transmute americium (CerMet fuel target). The behaviour of molybdenum looks satisfying at operating temperature but at high temperature (above 1000 °C) more investigation should be performed.

  12. HELIOS: the new design of the irradiation of U-free fuels for americium transmutation

    Energy Technology Data Exchange (ETDEWEB)

    D' Agata, E. [European Commission, Joint Research Centre, Institute for Energy, P.O. Box 2, 1755 ZG Petten (Netherlands); Klaassen, F.; Sciolla, C. [Nuclear Research and Consultancy Group, Dept. Life Cycle and Innovations, P.O. Box 25 1755 ZG Petten (Netherlands); Fernandez-Carretero, A. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Bonnerot, J.M. [Commissariat a l' Energie Atomique, DEC/SESC/LC2I CEA-Cadarache, 13108 St. Paul lez Durance Cedex (France)

    2009-06-15

    Americium is one of the radioactive elements that mostly contribute to the radiotoxicity of the nuclear spent fuel. Transmutation of long-lived nuclides like Americium is an option for the reduction of the mass, the radiotoxicity and the decay heat of nuclear waste. The HELIOS irradiation experiment is the last evolution in a series of experiments on americium transmutation. The previous experiments, EFTTRA-T4 and T4bis, have shown that the release or trapping of helium is the key issue for the design of such kind of target. In fact, the production of helium, which is characteristic of {sup 241}Am transmutation, is quite significant. The experiment is carried out in the framework of the 4-year project EUROTRANS of the EURATOM 6. Framework Programme (FP6). Therefore, the main objective of the HELIOS experiment is to study the in-pile behaviour of U-free fuels such as CerCer (Pu, Am, Zr)O{sub 2} and Am{sub 2}Zr{sub 2}O{sub 7}+MgO or CerMet (Pu, Am)O{sub 2}+Mo in order to gain knowledge on the role of the fuel microstructure and of the temperature on the gas release and on the fuel swelling. The experiment was planned to be conducted in the HFR (High Flux Reactor) in Petten (The Netherlands) starting the first quarter of 2007. Because of the innovative aspects of the fuel, the fabrication has had some delays as well as the final safety analyses of the original design showed some unexpected deviation. Besides, the HFR reactor has been unavailable since August 2008. Due to the reasons described above, the experiment has been postponed. HELIOS should start in the first quarter of 2009 and will last 300 full power days. The paper will cover the description of the new design of the irradiation experiment HELIOS. The experiment has been split in two parts (HELIOS1 and HELIOS2) which will be irradiated together. Moreover, due to the high temperature achieved in cladding and to the high amount of helium produced during transmutation the experiment previously designed for a

  13. Americium and plutonium in water, biota, and sediment from the central Oregon coast

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, R. D.

    1982-06-01

    Plutonium-239, 240 and americium-241 were measured in the mussel Mytilus californianus from the region of Coos Bay, OR. The flesh of this species has a plutonium concentration of about 90 fCi/kg, and an Am-241/Pu-239, 240 ratio that is high relative to mixed fallout, ranging between two and three. Transuranic concentrations in sediment, unfiltered water, and filterable particulates were also measured; none of these materials has an Am/Pu ratio as greatly elevated as the mussels, and there is no apparent difference in the Am/Pu ratio of terrestrial runoff and coastal water. Sediment core profiles do not allow accumulation rates or depositional histories to be identified, but it does not appear that material characterized by a high Am/Pu ratio has ever been introduced to this estuary. Other bivalves (Tresus capax and Macoma nasuta) and a polychaete (Abarenicola sp.) do not have an elevated Am/Pu ratio, although the absolute activity of plutonium in the infaunal bivalves is roughly four times that in the mussels.

  14. Americium-based oxides: Dense pellet fabrication from co-converted oxalates

    Energy Technology Data Exchange (ETDEWEB)

    Horlait, Denis; Lebreton, Florent [CEA, DEN, DTEC/SDTC/LEMA, 30207 Bagnols-sur-Cèze (France); Gauthé, Aurélie [CEA, DEN, DRCP/SERA/LCAR, 30207 Bagnols-sur-Cèze (France); Caisso, Marie [CEA, DEN, DTEC/SDTC/LEMA, 30207 Bagnols-sur-Cèze (France); Arab-Chapelet, Bénédicte; Picart, Sébastien [CEA, DEN, DRCP/SERA/LCAR, 30207 Bagnols-sur-Cèze (France); Delahaye, Thibaud, E-mail: thibaud.delahaye@cea.fr [CEA, DEN, DTEC/SDTC/LEMA, 30207 Bagnols-sur-Cèze (France)

    2014-01-15

    Mixed oxides are used as nuclear fuels and are notably envisaged for future fuel cycles including plutonium and minor actinide recycling. In this context, processes are being developed for the fabrication of uranium–americium mixed-oxide compounds for transmutation. The purpose of these processes is not only the compliance with fuel specifications in terms of density and homogeneity, but also the simplification of the process for its industrialization as well as lowering dust generation. In this paper, the use of a U{sub 0.85}Am{sub 0.15}O{sub 2±δ} powder synthesized by oxalate co-conversion as a precursor for dense fuel fabrications is assessed. This study notably focuses on sintering, which yielded pellets up to 96% of the theoretical density, taking advantage of the high reactivity and homogeneity of the powder. As-obtained pellets were further characterized to be compared to those obtained via processes based on the UMACS (Uranium Minor Actinide Conventional Sintering) process. This comparison highlights several advantages of co-converted powder as a precursor for simplified processes that generate little dust.

  15. Experimental studies on the biokinetics of plutonium and americium in the cephalopod Octopus vulgaris

    Energy Technology Data Exchange (ETDEWEB)

    Guary, J.C.; Fowler, S.W.

    1982-03-05

    Radiotracer experiments using the photon-emitters /sup 237/Pu and /sup 241/Am were performed to examine uptake, tissue distribution and retention of plutonium and americium in the cephalopod Octopus vulgaris Cuvier. A 2 wk exposure in contaminated sea water resulted in twice as much /sup 237/Pu being taken up by whole octopus as /sup 241/Am. Immediately following uptake approximately 41% and 73% of the /sup 237/Pu and /sup 241/Am respectively were located in the branchial hearts. Depuration rates for both radionuclides were identical; approximately 46% of both radionuclides initially incorporated were associated with a long-lived compartment which turned over very slowly (Tbsub(1/2) = 1.5 yr). Longer exposures to /sup 241/Am resulted in an increase in the size of the slowly exchanging /sup 241/Am pool in the octopus. After 2 mo depuration, the majority of the residual activity of both radionuclides was in the branchial hearts. On average 33% of the /sup 241/Am ingested with food was assimilated into tissues, primarily the hepatopancreas. Different whole-body /sup 241/Am excretion rates were observed at different times following assimilation and were related to transfer processes taking place within internal tissues, most notably between hepatopancreas and the branchial hearts. Relationships between circulatory and excretory functions of these 2 organs are discussed and a physiological mechanism is proposed to explain the observed patterns of /sup 241/Am excretion in O. vulgaris.

  16. In Vitro Dissolution Tests of Plutonium and Americium Containing Contamination Originating From ZPPR Fuel Plates

    Energy Technology Data Exchange (ETDEWEB)

    William F. Bauer; Brian K. Schuetz; Gary M. Huestis; Thomas B. Lints; Brian K. Harris; R. Duane Ball; Gracy Elias

    2012-09-01

    Assessing the extent of internal dose is of concern whenever workers are exposed to airborne radionuclides or other contaminants. Internal dose determinations depend upon a reasonable estimate of the expected biological half-life of the contaminants in the respiratory tract. One issue with refractory elements is determining the dissolution rate of the element. Actinides such as plutonium (Pu) and Americium (Am) tend to be very refractory and can have biological half-lives of tens of years. In the event of an exposure, the dissolution rates of the radionuclides of interest needs to be assessed in order to assign the proper internal dose estimates. During the November 2011 incident at the Idaho National Laboratory (INL) involving a ZPPR fuel plate, air filters in a constant air monitor (CAM) and a giraffe filter apparatus captured airborne particulate matter. These filters were used in dissolution rate experiments to determine the apparent dissolution half-life of Pu and Am in simulated biological fluids. This report describes these experiments and the results. The dissolution rates were found to follow a three term exponential decay equation. Differences were noted depending upon the nature of the biological fluid simulant. Overall, greater than 95% of the Pu and 93% of the Am were in a very slow dissolving component with dissolution half-lives of over 10 years.

  17. Plutonium and americium monazite materials: Solid state synthesis and X-ray diffraction study

    Energy Technology Data Exchange (ETDEWEB)

    Bregiroux, D. [DEN/DEC/SPUA, Commissariat a l' Energie Atomique, Cadarache, 13108 Saint Paul Lez Durance (France); Laboratoire Science des Procedes Ceramiques et de Traitements de Surface, UMR CNRS-Universite no. 6638, Batiment Chimie, 123 avenue Albert Thomas, 87060 Limoges (France); E-mail: damien.bregiroux@ccr.jussieu.fr; Belin, R. [DEN/DEC/SPUA, Commissariat a l' Energie Atomique, Cadarache, 13108 Saint Paul Lez Durance (France); Valenza, P. [DEN/DEC/SPUA, Commissariat a l' Energie Atomique, Cadarache, 13108 Saint Paul Lez Durance (France); Audubert, F. [DEN/DEC/SPUA, Commissariat a l' Energie Atomique, Cadarache, 13108 Saint Paul Lez Durance (France); Bernache-Assollant, D. [Ecole Nationale Superieure des Mines, 158 Cours Fauriel, 42023 Saint Etienne (France)

    2007-06-30

    High-temperature solid state syntheses of monazite powders containing plutonium (III), plutonium (IV) and americium (III) were performed. Resulting powders were characterized by X-ray diffraction. Pu{sup 3+}PO{sub 4} was readily obtained as a single phase by heating a Pu{sup 4+}O{sub 2}-NH{sub 4}H{sub 2}PO{sub 4} mixture under argon atmosphere. Traces of tetravalent plutonium phosphate Pu{sup 4+}P{sub 2}O{sub 7} were detected when synthesized under air atmosphere. The incorporation of (Pu{sup 4+},Ca{sup 2+}) in the monazite structure was investigated under air and argon atmosphere. We showed that Pu{sup 4+} is fully reduced in Pu{sup 3+} under argon atmosphere whereas, under air, the compound with the formula Pu{sub 0.4}{sup 3+}Pu{sub 0.3}{sup 4+}Ca{sub 0.3}{sup 2+}PO{sub 4} was obtained. Pure Am{sup 3+}PO{sub 4} was also synthesized under argon atmosphere. X-ray patterns revealed a complete amorphisation of the monazite structure at a relatively low cumulative alpha dose for {sup 241}AmPO{sub 4}.

  18. Mutual separation of americium(III) and europium(III) using glycolamic acid and thioglycolamic acid

    Energy Technology Data Exchange (ETDEWEB)

    Suneesh, A.S.; Venkatesan, K.A.; Syamala, K.V.; Antony, M.P.; Vasudeva Rao, P.R. [Indira Gandhi Centre for Atomic Research, Kalpakkam (India). Fuel Chemistry Div.

    2012-07-01

    The extractants, bis(2-ethylhexyl)diglycolamicacid (HDEHDGA) and bis(2-ethylhexy)thiodiglycolamic acid (HDEHSDGA) were synthesized and characterized by {sup 1}H and {sup 13}C NMR, mass and IR spectroscopy. The extraction behaviour of {sup (152+154})Eu(III) and {sup 241}Am(III) from nitric acid medium by a solution of HDEHDGA (or HDEHSDGA) in n-dodecane (n-DD) was studied for the mutual separation of actinides and lanthanides. The effect of various parameters such as the pH, concentrations of HDEHDGA, HDEHSDGA, sodium nitrate, N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) and diethylenetriaminepentaacetic acid (DTPA) on the separation factor (SF) of americium(III) over europium(III) and vice versa was studied, and the conditions needed for the preferential separation were optimised. The results show that HDEHDGA exhibits higher extraction for {sup (152+154)}Eu(III) and HDEHSDGA shows the superior selectivity for {sup 241}Am(III). (orig.)

  19. Solution speciation of plutonium and Americium at an Australian legacy radioactive waste disposal site.

    Science.gov (United States)

    Ikeda-Ohno, Atsushi; Harrison, Jennifer J; Thiruvoth, Sangeeth; Wilsher, Kerry; Wong, Henri K Y; Johansen, Mathew P; Waite, T David; Payne, Timothy E

    2014-09-01

    During the 1960s, radioactive waste containing small amounts of plutonium (Pu) and americium (Am) was disposed in shallow trenches at the Little Forest Burial Ground (LFBG), located near the southern suburbs of Sydney, Australia. Because of periodic saturation and overflowing of the former disposal trenches, Pu and Am have been transferred from the buried wastes into the surrounding surface soils. The presence of readily detected amounts of Pu and Am in the trench waters provides a unique opportunity to study their aqueous speciation under environmentally relevant conditions. This study aims to comprehensively investigate the chemical speciation of Pu and Am in the trench water by combining fluoride coprecipitation, solvent extraction, particle size fractionation, and thermochemical modeling. The predominant oxidation states of dissolved Pu and Am species were found to be Pu(IV) and Am(III), and large proportions of both actinides (Pu, 97.7%; Am, 86.8%) were associated with mobile colloids in the submicron size range. On the basis of this information, possible management options are assessed.

  20. Americium/Lanthanide Separations in Alkaline Solutions for Advanced Nuclear Fuel Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Goff, George S. [Los Alamos National Laboratory; Long, Kristy Marie [Los Alamos National Laboratory; Reilly, Sean D. [Los Alamos National Laboratory; Jarvinen, Gordon D. [Los Alamos National Laboratory; Runde, Wolfgang H. [Los Alamos National Laboratory

    2012-06-11

    Project goals: Can used nuclear fuel be partitioned by dissolution in alkaline aqueous solution to give a solution of uranium, neptunium, plutonium, americium and curium and a filterable solid containing nearly all of the lanthanide fission products and certain other fission products? What is the chemistry of Am/Cm/Ln in oxidative carbonate solutions? Can higher oxidation states of Am be stabilized and exploited? Conclusions: Am(VI) is kinetically stable in 0.5-2.0 M carbonate solutions for hours. Aliquat 336 in toluene has been successfully shown to extract U(VI) and Pu(VI) from carbonate solutions. (Stepanov et al 2011). Higher carbonate concentration gives lower D, SF{sub U/Eu} for = 4 in 1 M K{sub 2}CO{sub 3}. Experiments with Am(VI) were unsuccessful due to reduction by the organics. Multiple sources of reducing organics...more optimization. Reduction experiments of Am(VI) in dodecane/octanol/Aliquat 336 show that after 5 minutes of contact, only 30-40% of the Am(VI) has been reduced. Long enough to perform an extraction. Shorter contact times, lower T, and lower Aliquat 336 concentration still did not result in any significant extraction of Am. Anion exchange experiments using a strong base anion exchanger show uptake of U(VI) with minimal uptake of Nd(III). Experiments with Am(VI) indicate Am sorption with a Kd of 9 (10 minute contact) but sorption mechanism is not yet understood. SF{sub U/Nd} for = 7 and SF{sub U/Eu} for = 19 after 24 hours in 1 M K{sub 2}CO{sub 3}.

  1. Concentrations of plutonium and americium in plankton from the western Mediterranean Sea

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Cabeza, Joan-Albert; Merino, Juan; Masque, Pere [Insitut de Ciencia i Tecnologia Ambiental-Departament de Fisica, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain); Mitchell, Peter I.; Vintro, L. Leon [Department of Experimental Physics, University College Dublin, Dublin 4 (Ireland); Schell, William R. [Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Cross, Lluisa; Calbet, Albert [Institut de Ciencies del Mar, Pg. Maritim Barceloneta, 37-49 08003, Barcelona (Spain)

    2003-07-20

    Understanding the transfer of radionuclides through the food chain leading to man and in particular, the uptake of transuranic nuclides by plankton, is basic to assess the potential radiological risk of the consumption of marine products by man. The main sources of transuranic elements in the Mediterranean Sea in the past were global fallout and the Palomares accident, although at present smaller amounts are released from nuclear establishments in the northwestern region. Plankton from the western Mediterranean Sea was collected and analyzed for plutonium and americium in order to study their biological uptake. The microplankton fractions accounted for approximately 50% of the total plutonium contents in particulate form. At Garrucha (Palomares area), microplankton showed much higher {sup 239,240}Pu activity, indicating the contamination with plutonium from the bottom sediments. Concentration factors were within the range of the values recommended by the International Atomic Energy Agency. Continental shelf mesoplankton was observed to efficiently concentrate transuranics. In open seawaters, concentrations were much lower. We speculate that sediments might play a role in the transfer of transuranics to mesoplankton in coastal waters, although we cannot discard that the difference in species composition may also play a role. In Palomares, both {sup 239,240}Pu and {sup 241}Am showed activities five times higher than the mean values observed in continental shelf mesoplankton. As the plutonium isotopic ratios in the contaminated sample were similar to those found in material related to the accident, the contamination was attributed to bomb debris from the Palomares accident. Concentration factors in mesoplankton were also in relatively good agreement with the ranges recommended by IAEA. In the Palomares station the highest concentration factor was observed in the sample that showed predominance of the dynoflagellate Ceratium spp. Mean values of the enrichment factors

  2. In situ characterization of uranium and americium oxide solid solution formation for CRMP process: first combination of in situ XRD and XANES measurements.

    Science.gov (United States)

    Caisso, Marie; Picart, Sébastien; Belin, Renaud C; Lebreton, Florent; Martin, Philippe M; Dardenne, Kathy; Rothe, Jörg; Neuville, Daniel R; Delahaye, Thibaud; Ayral, André

    2015-04-14

    Transmutation of americium in heterogeneous mode through the use of U1-xAmxO2±δ ceramic pellets, also known as Americium Bearing Blankets (AmBB), has become a major research axis. Nevertheless, in order to consider future large-scale deployment, the processes involved in AmBB fabrication have to minimize fine particle dissemination, due to the presence of americium, which considerably increases the risk of contamination. New synthesis routes avoiding the use of pulverulent precursors are thus currently under development, such as the Calcined Resin Microsphere Pelletization (CRMP) process. It is based on the use of weak-acid resin (WAR) microspheres as precursors, loaded with actinide cations. After two specific calcinations under controlled atmospheres, resin microspheres are converted into oxide microspheres composed of a monophasic U1-xAmxO2±δ phase. Understanding the different mechanisms during thermal conversion, that lead to the release of organic matter and the formation of a solid solution, appear essential. By combining in situ techniques such as XRD and XAS, it has become possible to identify the key temperatures for oxide formation, and the corresponding oxidation states taken by uranium and americium during mineralization. This paper thus presents the first results on the mineralization of (U,Am) loaded resin microspheres into a solid solution, through in situ XAS analysis correlated with HT-XRD.

  3. LIBS Spectral Data for a Mixed Actinide Fuel Pellet Containing Uranium, Plutonium, Neptunium and Americium

    Energy Technology Data Exchange (ETDEWEB)

    Judge, Elizabeth J. [Los Alamos National Laboratory; Berg, John M. [Los Alamos National Laboratory; Le, Loan A. [Los Alamos National Laboratory; Lopez, Leon N. [Los Alamos National Laboratory; Barefield, James E. [Los Alamos National Laboratory

    2012-06-18

    Laser-induced breakdown spectroscopy (LIBS) was used to analyze a mixed actinide fuel pellet containing 75% UO{sub 2}/20% PuO{sub 2}/3% AmO{sub 2}/2% NpO{sub 2}. The preliminary data shown here is the first report of LIBS analysis of a mixed actinide fuel pellet, to the authors knowledge. The LIBS spectral data was acquired in a plutonium facility at Los Alamos National Laboratory where the sample was contained within a glove box. The initial installation of the glove box was not intended for complete ultraviolet (UV), visible (VIS) and near infrared (NIR) transmission, therefore the LIBS spectrum is truncated in the UV and NIR regions due to the optical transmission of the window port and filters that were installed. The optical collection of the emission from the LIBS plasma will be optimized in the future. However, the preliminary LIBS data acquired is worth reporting due to the uniqueness of the sample and spectral data. The analysis of several actinides in the presence of each other is an important feature of this analysis since traditional methods must chemically separate uranium, plutonium, neptunium, and americium prior to analysis. Due to the historic nature of the sample fuel pellet analyzed, the provided sample composition of 75% UO{sub 2}/20% PuO{sub 2}/3% AmO{sub 2}/2% NpO{sub 2} cannot be confirm without further analytical processing. Uranium, plutonium, and americium emission lines were abundant and easily assigned while neptunium was more difficult to identify. There may be several reasons for this observation, other than knowing the exact sample composition of the fuel pellet. First, the atomic emission wavelength resources for neptunium are limited and such techniques as hollow cathode discharge lamp have different dynamics than the plasma used in LIBS which results in different emission spectra. Secondly, due to the complex sample of four actinide elements, which all have very dense electronic energy levels, there may be reactions and

  4. THE FIRST ISOLATION OF AMERICIUM IN THE FORM OF PURE COMPOUNDS - THE SPECIFIC ALPHA-ACTIVITY AND HALF-LIFE OF Am241

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, B.B.; Asprey, L.B.

    1950-07-20

    The microgram scale isolation and preparation of pure compounds of americium is described. Data are presented to show that the alpha-half-life of the isotope Am{sup 241} is 490 {+-} 14 years. The absorption spectrum of Am(III) in 1M nitric acid in the range 3500-8000 mu is given. The wave lengths of 10 of the most prominent lines in the copper spark emission spectrum of americium are given to the nearest 0.01 {angstrom}. Evidence is presented to show that the potential for the Am(III)-Am(IV) couple in acid solution is more negative than -2v and that the potential for the Am(II)-Am(III) couple is more positive than +0.9v.

  5. Food additives

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002435.htm Food additives To use the sharing features on this page, please enable JavaScript. Food additives are substances that become part of a food ...

  6. Response of avalanche photo-diodes of the CMS Electromagnetic Calorimeter to neutrons from an Americium-Beryllium source.

    CERN Document Server

    Deiters, Konrad; Renker, Dieter

    2010-01-01

    The response of avalanche photo-diodes (APDs) used in the CMS Electromagnetic Calorimeter to low energy neutrons from an Americium-Beryllium source is reported. Signals due to recoil protons from neutron interactions with the hydrogen nuclei in the protective epoxy layer, mainly close to the silicon surface of the APD, have been identified. These signals increase in size with the applied bias voltage more slowly than the nominal gain of the APDs, and appear to have a substantially lower effective gain at the operating voltage. The signals originating from interactions in the epoxy are mostly equivalent to signals of a few GeV in CMS, but range up to a few tens of GeV equivalent. There are also signals not attributed to reactions in the epoxy extending up to the end of the range of these measurements, a few hundreds of GeV equivalent. Signals from the x-rays from the source can also be in the GeV equivalent scale in CMS. Simulations used to describe events due to particle interactions in the APDs need to take ...

  7. Nano-cerium vanadate: a novel inorganic ion exchanger for removal of americium and uranium from simulated aqueous nuclear waste.

    Science.gov (United States)

    Banerjee, Chayan; Dudwadkar, Nilesh; Tripathi, Subhash Chandra; Gandhi, Pritam Maniklal; Grover, Vinita; Kaushik, Chetan Prakash; Tyagi, Avesh Kumar

    2014-09-15

    Cerium vanadate nanopowders were synthesized by a facile low temperature co-precipitation method. The product was characterized by X-ray diffraction and transmission electron microscopy and found to consist of ∼25 nm spherical nanoparticles. The efficiency of these nanopowders for uptake of alpha-emitting radionuclides (233)U (4.82 MeV α) and (241)Am (5.49 MeV α, 60 keV γ) has been investigated. Thermodynamically and kinetically favorable uptake of these radionuclides resulted in their complete removal within 3h from aqueous acidic feed solutions. The uptake capacity was observed to increase with increase in pH as the zeta potential value decreased with the increase in pH but effect of ionic strength was insignificant. Little influence of the ions like Sr(2+), Ru(3+), Fe(3+), etc., in the uptake process indicated CeVO4 nanopowders to be amenable for practical applications. The isotherms indicated predominant uptake of the radioactive metal ions in the solid phase of the exchanger at lower feed concentrations and linear Kielland plots with positive slopes indicated favorable exchange of the metal ions with the nanopowder. Performance comparison with the other sorbents reported indicated excellent potential of nano-cerium vanadate for removing americium and uranium from large volumes of aqueous acidic solutions.

  8. Additivity dominance

    Directory of Open Access Journals (Sweden)

    Paul Rozin

    2009-10-01

    Full Text Available Judgments of naturalness of foods tend to be more influenced by the process history of a food, rather than its actual constituents. Two types of processing of a ``natural'' food are to add something or to remove something. We report in this study, based on a large random sample of individuals from six countries (France, Germany, Italy, Switzerland, UK and USA that additives are considered defining features of what makes a food not natural, whereas ``subtractives'' are almost never mentioned. In support of this, skim milk (with major subtraction of fat is rated as more natural than whole milk with a small amount of natural vitamin D added. It is also noted that ``additives'' is a common word, with a synonym reported by a native speaker in 17 of 18 languages, whereas ``subtractive'' is lexicalized in only 1 of the 18 languages. We consider reasons for additivity dominance, relating it to omission bias, feature positive bias, and notions of purity.

  9. Determination by gamma-ray spectrometry of the plutonium and americium content of the Pu/Am separation scraps. Application to molten salts; Determination par spectrometrie gamma de la teneur en plutonium et en americium de produits issus de separation Pu/Am. Application aux bains de sels

    Energy Technology Data Exchange (ETDEWEB)

    Godot, A. [CEA Valduc, Dept. de Traitement des Materiaux Nucleaires, 21 - Is-sur-Tille (France); Perot, B. [CEA Cadarache, Dept. de Technologie Nucleaire, Service de Modelisation des Transferts et Mesures Nucleaires, 13 - Saint-Paul-lez-Durance (France)

    2005-07-01

    Within the framework of plutonium recycling operations in CEA Valduc (France), americium is extracted from molten plutonium metal into a molten salt during an electrolysis process. The scraps (spent salt, cathode, and crucible) contain extracted americium and a part of plutonium. Nuclear material management requires a very accurate determination of the plutonium content. Gamma-ray spectroscopy is performed on Molten Salt Extraction (MSE) scraps located inside the glove box, in order to assess the plutonium and americium contents. The measurement accuracy is influenced by the device geometry, nuclear instrumentation, screens located between the sample and the detector, counting statistics and matrix attenuation, self-absorption within the spent salt being very important. The purpose of this study is to validate the 'infinite energy extrapolation' method employed to correct for self-attenuation, and to detect any potential bias. We present a numerical study performed with the MCNP computer code to identify the most influential parameters and some suggestions to improve the measurement accuracy. A final uncertainty of approximately 40% is achieved on the plutonium mass. (authors)

  10. Transfer across the human gut of environmental plutonium, americium, cobalt, caesium and technetium: studies with cockles (Cerastoderma edule) from the Irish Sea.

    Science.gov (United States)

    Hunt, G J

    1998-06-01

    Our previous studies have indicated lower values of the gut transfer factor ('f1 values') for plutonium and americium in winkles (Littorina littorea) than adopted by ICRP. The present study was undertaken primarily to investigate whether this observation extends to other species. Samples of cockles (Carastoderma edule) from Ravenglass, Cumbria were eaten by volunteers who provided 24 h samples of urine and faeces. Urine samples indicated f1 values for cockles which were higher than for winkles; for plutonium these ranged overall up to 7 x 10(-4) with an arithmetic mean in the range (2-3) x 10(-4), and for americium up to 2.6 x 10(-4) with an arithmetic mean of 1.2 x 10(-4). Limited data based on volunteers eating cockles from the Solway suggest that f1 values for americium may be greater at distance from Sellafield. The measured values compare with 5 x 10(-4) used by the ICRP for environmental forms of both elements, which would appear to provide adequate protection when calculating doses from Cumbrian cockles. Data for other nuclides were obtained by analysing faecal samples from the volunteers who ate the Ravenglass cockles. Cobalt-60 showed an f1 value in the region of 0.2, twice the value currently used by ICRP. For 137Cs, variabilities were indicated in the range 0.08 to 0.43, within the ICRP value of f1 = 1.0. Technetium-99 gave f1 values up to about 0.6, in reasonable conformity with the ICRP value of 0.5.

  11. Transfer across the human gut of environmental plutonium, americium, cobalt, caesium and technetium: studies with cockles (Cerastoderma edule) from the Irish Sea

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, G.J. [CEFAS Laboratory, Lowestoft, Suffolk NR33 0HT (United Kingdom)

    1998-06-01

    Our previous studies have indicated lower values of the gut transfer factor ('f{sub L} values') for plutonium and americium in winkles (Littorina littorea) than adopted by ICRP. The present study was undertaken primarily to investigate whether this observation extends to other species. Samples of cockles (Cerastoderma edule) from Ravenglass, Cumbria were eaten by volunteers who provided 24 samples of urine and faeces. Urine samples indicated f{sub L} values for cockles which were higher than for winkles; for plutonium these ranged overall up to 7x10{sup -4} with an arithmetic mean in the range (2-3)x10{sup -4}, and for americium up to 2.6x10{sup -4} with an arithmetic mean of 1.2x10{sup -4}. Limited data based on volunteers eating cockles from the Solway suggest that f{sub L} values for americium may be greater at distance from Sellafield. The measured values compare with 5x10{sup -4} used by the ICRP for environmental forms of both elements, which would appear to provide adequate protection when calculating doses from Cumbrian cockles. Data for other nuclides were obtained by analysing faecal samples from the volunteers who ate the Ravenglass cockles. Cobalt-60 showed an f{sub L} value in the region of 0.2, twice the value currently used by ICRP. For {sup 137}Cs, variabilities were indicated in the range 0.08 to 0.43, within the ICRP value of f{sub L}=1.0. Technetium-99 gave f{sub L} values up to about 0.6, in reasonable conformity with the ICRP value of 0.5. (author)

  12. Nano-cerium vanadate: A novel inorganic ion exchanger for removal of americium and uranium from simulated aqueous nuclear waste

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Chayan; Dudwadkar, Nilesh [Fuel Reprocessing Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Tripathi, Subhash Chandra, E-mail: sctri001@gmail.com [Fuel Reprocessing Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Gandhi, Pritam Maniklal [Fuel Reprocessing Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Grover, Vinita [Waste Management Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Kaushik, Chetan Prakash [Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Tyagi, Avesh Kumar, E-mail: aktyagi@barc.gov.in [Waste Management Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

    2014-09-15

    Highlights: • Template free, low temperature synthesis of CeVO{sub 4} nanopowders. • Thermodynamically and kinetically favourable uptake of Am(III) and U(VI) exhibited. • K{sub d} and ΔG° values for Am(III) and U(VI) uptake in pH 1–6 are reported. • Interdiffusion coefficients and zeta potential values in pH 1–6 are reported. • Possible application in low level aqueous nuclear waste remediation. - Abstract: Cerium vanadate nanopowders were synthesized by a facile low temperature co-precipitation method. The product was characterized by X-ray diffraction and transmission electron microscopy and found to consist of ∼25 nm spherical nanoparticles. The efficiency of these nanopowders for uptake of alpha-emitting radionuclides {sup 233}U (4.82 MeV α) and {sup 241}Am (5.49 MeV α, 60 keV γ) has been investigated. Thermodynamically and kinetically favorable uptake of these radionuclides resulted in their complete removal within 3 h from aqueous acidic feed solutions. The uptake capacity was observed to increase with increase in pH as the zeta potential value decreased with the increase in pH but effect of ionic strength was insignificant. Little influence of the ions like Sr{sup 2+}, Ru{sup 3+}, Fe{sup 3+}, etc., in the uptake process indicated CeVO{sub 4} nanopowders to be amenable for practical applications. The isotherms indicated predominant uptake of the radioactive metal ions in the solid phase of the exchanger at lower feed concentrations and linear Kielland plots with positive slopes indicated favorable exchange of the metal ions with the nanopowder. Performance comparison with the other sorbents reported indicated excellent potential of nano-cerium vanadate for removing americium and uranium from large volumes of aqueous acidic solutions.

  13. Plutonium, americium and radiocaesium in the marine environment close to the Vandellos I nuclear power plant before decommissioning

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez-Cabeza, J.A. E-mail: joanalbert.sanchez@uab.es; Molero, J

    2000-11-01

    The Vandellos nuclear power plant (NPP), releasing low-level radioactive liquid waste to the Mediterranean Sea, is the first to be decommissioned in Spain, after an incident which occurred in 1989. The presence, distribution and uptake of various artificial radionuclides (radiocaesium, plutonium and americium) in the environment close to the plant were studied in seawater, bottom sediments and biota, including Posidonia oceanica, fish, crustaceans and molluscs. Seawater, sediments and Posidonia oceanica showed enhanced levels in the close vicinity of the NPP, although the effect was restricted to its near environment. Maximum concentrations in seawater were 11.6{+-}0.5 Bq m{sup -3} and 16.9{+-}1.2 mBq m{sup -3} for {sup 137}Cs and {sup 239,240}Pu, respectively. When sediment concentrations were normalized to excess {sup 210}Pb, they showed both the short-distance transport of artificial radionuclides from the Vandellos plant and the long-distance transport of {sup 137}Cs from the Asco NPP. Posidonia oceanica showed the presence of various gamma-emitters attributed to the impact of the Chernobyl accident, on which the effect of the NPP was superimposed. Seawater, sediment and Posidonia oceanica collected near the plant also showed an enhancement of the plutonium isotopic ratio above the fallout value. The uptake of these radionuclides by marine organisms was detectable but limited. Pelagic fish showed relatively higher {sup 137}Cs concentrations and only in the case of demersal fish was the plutonium isotopic ratio increased. The reported levels constitute a set of baseline values against which the impact of the decommissioning operations of the Vandellos I NPP can be studied.

  14. Potlining Additives

    Energy Technology Data Exchange (ETDEWEB)

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  15. Additivity dominance

    OpenAIRE

    2009-01-01

    Judgments of naturalness of foods tend to be more influenced by the process history of a food, rather than its actual constituents. Two types of processing of a ``natural'' food are to add something or to remove something. We report in this study, based on a large random sample of individuals from six countries (France, Germany, Italy, Switzerland, UK and USA) that additives are considered defining features of what makes a food not natural, whereas ``subtractives'' are almost never mentioned....

  16. Vertical distribution of radiocaesium, plutonium and americium in the Catalan Sea (northwestern Mediterranean)

    Energy Technology Data Exchange (ETDEWEB)

    Molero, J.; Sanchez-Cabeza, J.A.; Merino, J.; Pujol, Ll.; Vidal-Quadras, A. [Universidad Autonoma de Barcelona (Spain). Facultad de Ciencias; Mitchell, P.I. [University Coll., Dublin (Ireland). Lab. of Radiation Physics

    1995-07-01

    Caesium-137, {sup 239,240}Pu and {sup 241}Am concentration profiles (0-1000 m) have been determined in unfiltered large volume water samples collected from the Catalan Sea (northwestern Mediterranean). Results showed that radiocaesium concentration decreases quickly through the water column while the transuranic concentration increases with depth, showing a faster migration to the bottom layers. Comparing our results with those reported by other authors (1975-1980), radiocaesium input from Chernobyl releases has been identified through the profile. In addition, transuranic concentrations have decreased considerably in the different layers of the profile. (Author).

  17. Americium-241 and plutonium-237 turnover in mussels ( Mytilus galloprovincialis) living in field enclosures

    Science.gov (United States)

    Guary, J. C.; Fowler, S. W.

    1981-02-01

    Loss of 241Am and 237Pu from contaminated mussels ( Mytilus galloprovincialis) living in situ in the Mediterranean Sea is described as the sum of three exponential functions. In the case of 241Am, two short-lived compartments representing a total of 80% of the incorporated radionuclide turned over rapidly with biological half-lives of 2 and 3 weeks. The remaining fraction of 241Am, associated with a long-lived compartment, was lost at an extremely slow rate ( Tb1/2=1·3 years). Plutonium-237 turnover in the two short-lived compartments (containing 70% of the Pu) was more rapid ( Tb1/2=1-2 days and 2 weeks) than that of 241Am; however, there was some indication that subsequent loss rates of the two radionuclides in long-lived compartments may be similar if determined over comparable periods of time. Loss rates of 241Am differed for the various tissues, with the most rapid rates occurring in gill, viscera and shell. Abrupt changes in loss observed in muscle and mantle suggested a translocation of 241Am to muscle and mantle during depuration. Whole shell contained by far the largest fraction (˜90%) of both 241Am and 237Pu taken up; in addition, these radionuclides are not irreversibly bound to mussel shell but readily leach into the water. These observations suggest that mollusc shell may influence the biogeochemistry of transuranic elements in littoral zones.

  18. Concordant plutonium-241-americium-241 dating of environmental samples: results from forest fire ash

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, Steven J [Los Alamos National Laboratory; Oldham, Warren J [Los Alamos National Laboratory; Murrell, Michael T [Los Alamos National Laboratory; Katzman, Danny [Los Alamos National Laboratory

    2010-12-07

    in NTS weapons testing at that time. The age results for this component are in agreement using both {sup 242}Pu and {sup 151}Sm normalizations, although the errors for the {sup 151}Sm correction are currently larger due to the greater uncertainty of their measurements. Additional efforts to develop a concordant {sup 241}Pu-{sup 241}Am dating method for environmental collections are underway with emphasis on soil cores.

  19. The structures of CyMe4-BTBP complexes of americium(iii) and europium(iii) in solvents used in solvent extraction, explaining their separation properties.

    Science.gov (United States)

    Ekberg, Christian; Löfström-Engdahl, Elin; Aneheim, Emma; Foreman, Mark R StJ; Geist, Andreas; Lundberg, Daniel; Denecke, Melissa; Persson, Ingmar

    2015-11-14

    Separation of trivalent actinoid (An(iii)) and lanthanoid (Ln(iii)) ions is extremely challenging due to their similar ionic radii and chemical properties. Poly-aromatic nitrogen compounds acting as tetradentate chelating ligands to the metal ions in the extraction, have the ability to sufficiently separate An(iii) from Ln(iii). One of these compounds, 6,6'-bis(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-benzol[1,2,4]triazin-3-yl)[2,2]bipyridine, CyMe4-BTBP, has proven to be resistant towards acidic environments and strong radiation from radioactive decomposition. EXAFS studies of the dicomplexes of CyMe4-BTBP with americium(iii) and europium(iii) in nitrobenzene, cyclohexanone, 1-hexanol, 1-octanol and malonamide (DMDOHEMA) in 1-octanol have been carried out to get a deeper understanding of the parameters responsible for the separation. The predominating complexes independent of solvent used are [Am(CyMe4-BTBP)2(NO3)](2+) and [Eu(CyMe4-BTBP)2](3+), respectively, which are present as outer-sphere ion-pairs with nitrate ions in the studied solvents with low relative permittivity. The presence of a nitrate ion in the first coordination sphere of the americium(iii) complex compensates the charge density of the complex considerably in comparison when only outer-sphere ion-pairs are formed as for the [Eu(CyMe4-BTBP)2](3+) complex. The stability and solubility of a complex in a solvent with low relative permittivity increase with decreasing charge density. The [Am(CyMe4-BTBP)2(NO3)](2+) complex will therefore be increasingly soluble and stabilized over the [Eu(CyMe4-BTBP)2](3+) complex in solvents with decreasing relative permittivity of the solvent. The separation of americium(iii) from europium(iii) with CyMe4-BTBP as extraction agent will increase with decreasing relative permittivity of the solvent, and thereby also with decreasing solubility of CyMe4-BTBP. The choice of solvent is therefore a balance of a high separation factor and sufficient solubility of the CyMe4-BTBP

  20. Determination of Atto- to Femtogram Levels of Americium and Curium Isotopes in Large-Volume Urine Samples by Compact Accelerator Mass Spectrometry.

    Science.gov (United States)

    Dai, Xiongxin; Christl, Marcus; Kramer-Tremblay, Sheila; Synal, Hans-Arno

    2016-03-01

    Ultralow level analysis of actinides in urine samples may be required for dose assessment in the event of internal exposures to these radionuclides at nuclear facilities and nuclear power plants. A new bioassay method for analysis of sub-femtogram levels of Am and Cm in large-volume urine samples was developed. Americium and curium were co-precipitated with hydrous titanium oxide from the urine matrix and purified by column chromatography separation. After target preparation using mixed titanium/iron oxides, the final sample was measured by compact accelerator mass spectrometry. Urine samples spiked with known quantities of Am and Cm isotopes in the range of attogram to femtogram levels were measured for method evaluation. The results are in good agreement with the expected values, demonstrating the feasibility of compact accelerator mass spectrometry (AMS) for the determination of minor actinides at the levels of attogram/liter in urine samples to meet stringent sensitivity requirements for internal dosimetry assessment.

  1. Artificial radionuclides in the Northern European Marine Environment. Distribution of radiocaesium, plutonium and americium in sea water and sediments in 1995

    Energy Technology Data Exchange (ETDEWEB)

    Groettheim, Siri

    2000-07-01

    This study considers the distribution of radiocaesium, plutonium and americium in the northern marine environment. The highest radiocaesium activity in sea water was observed in Skagerrak, 26 Bq/m{sub 3}, and in surface sediments in the Norwegian Sea, 60 Bq/kg. These enhanced levels were related to Chernobyl. The highest 239,240Pu activity in surface water was measured in the western North Sea, 66 mBq/m{sub 3}. In sea water, sub-surface maxima were observed at several locations with an 239,240Pu activity up to 160 mBq/m{sub 3}, and were related to Sellafield. With the exception to the North Sea, surface sediments reflected Pu from global fallout from weapons tests only. (author)

  2. Development of an automatic method for americium and plutonium separation and preconcentration using an multisyringe flow injection analysis-multipumping flow system.

    Science.gov (United States)

    Fajardo, Yamila; Ferrer, Laura; Gómez, Enrique; Garcias, Francesca; Casas, Monserrat; Cerdà, Víctor

    2008-01-01

    A new procedure for automatic separation and preconcentration of 241Am and 239+240Pu from interfering matrixes using transuranide (TRU)-resin is proposed. Combination of the multisyringe flow injection analysis and multipumping flow system techniques with the TRU-resin allows carrying out the sampling treatment and separation in a short time using large sample volumes. Americium is eluted from the column with 4 mol L(-1) hydrochloric acid, and then plutonium is separated via on-column Pu(IV) reduction to Pu(III) with titanium(III) chloride. The corresponding alpha activities are measured off-line, with a relative standard deviation of 3% and a lower limit of detection of 0.004 Bq mL(-1), by using a multiplanchet low-background proportional counter.

  3. Recovery of Americium-241 from lightning rod by the method of chemical treatment; Recuperacion del Americio-241 provenientes de los pararrayos por el metodo de tratamiento quimico

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, W.H., E-mail: wcruz@ipen.gob.pe [Instituto Peruano de Energia Nuclear (GRRA/IPEN), Lima (Peru). Division de Gestion de Residuos Radiactivos

    2013-07-01

    About 95% of the lightning rods installed in the Peruvian territory have set in their structures, pose small amounts of radioactive sources such as Americium-241 ({sup 241}Am), fewer and Radium 226 ({sup 226}Ra) these are alpha emitters and have a half life of 432 years and 1600 years respectively. In this paper describes the recovery of radioactive sources of {sup 241}Am radioactive lightning rods using the conventional chemical treatment method using agents and acids to break down the slides. The {sup 241}Am recovered was as excitation source and alpha particle generator for analysing samples by X Ray Fluorescence, for fixing the stainless steel {sup 241}Am technique was used electrodeposition. (author)

  4. Americium-241 Decorporation Model

    Science.gov (United States)

    2014-10-01

    sources when combined with beryllium. Radioactive sources are used for a number of industrial applications that range from oil well logging devices...is any exposure resulting in a 50-year whole-body committed effective dose greater than 200 mSv (Rojas- Palma 2009). Therefore, the model can also...Tracheobronchial geometry: Human, dog, rat, hamster (Report LF-53). Lovelace Foundation, Albuquerque, NM Rojas- Palma C, et al. 2009. TMT Handbook

  5. Actinide Oxidation State and O/M Ratio in Hypostoichiometric Uranium-Plutonium-Americium U0.750Pu0.246Am0.004O2-x Mixed Oxides.

    Science.gov (United States)

    Vauchy, Romain; Belin, Renaud C; Robisson, Anne-Charlotte; Lebreton, Florent; Aufore, Laurence; Scheinost, Andreas C; Martin, Philippe M

    2016-03-07

    Innovative americium-bearing uranium-plutonium mixed oxides U1-yPuyO2-x are envisioned as nuclear fuel for sodium-cooled fast neutron reactors (SFRs). The oxygen-to-metal (O/M) ratio, directly related to the oxidation state of cations, affects many of the fuel properties. Thus, a thorough knowledge of its variation with the sintering conditions is essential. The aim of this work is to follow the oxidation state of uranium, plutonium, and americium, and so the O/M ratio, in U0.750Pu0.246Am0.004O2-x samples sintered for 4 h at 2023 K in various Ar + 5% H2 + z vpm H2O (z = ∼ 15, ∼ 90, and ∼ 200) gas mixtures. The O/M ratios were determined by gravimetry, XAS, and XRD and evidenced a partial oxidation of the samples at room temperature. Finally, by comparing XANES and EXAFS results to that of a previous study, we demonstrate that the presence of uranium does not influence the interactions between americium and plutonium and that the differences in the O/M ratio between the investigated conditions is controlled by the reduction of plutonium. We also discuss the role of the homogeneity of cation distribution, as determined by EPMA, on the mechanisms involved in the reduction process.

  6. Preliminary study of neutron absorption by concrete with boron carbide addition

    Energy Technology Data Exchange (ETDEWEB)

    Abdullah, Yusof, E-mail: yusofabd@nuclearmalaysia.gov.my; Yusof, Mohd Reusmaazran; Zali, Nurazila Mat; Ahmad, Megat Harun Al Rashid Megat; Yazid, Hafizal [Malaysian Nuclear Agency, Bangi, 43000 Kajang, Selangor (Malaysia); Ariffin, Fatin Nabilah Tajul; Ahmad, Sahrim [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor (Malaysia); Hamid, Roszilah [Department of Civil and Structural Engineering, Faculty of Engineering and Built Environment, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor (Malaysia); Mohamed, Abdul Aziz [College of Engineering, Universiti Tenaga National, Jalan Ikram-Uniten, 43000 Kajang, Selangor (Malaysia)

    2014-02-12

    Concrete has become a conventional material in construction of nuclear reactor due to its properties like safety and low cost. Boron carbide was added as additives in the concrete construction as it has a good neutron absorption property. The sample preparation for concrete was produced with different weight percent of boron carbide powder content. The neutron absorption rate of these samples was determined by using a fast neutron source of Americium-241/Be (Am-Be 241) and detection with a portable backscattering neutron detector. Concrete with 20 wt % of boron carbide shows the lowest count of neutron transmitted and this indicates the most neutrons have been absorbed by the concrete. Higher boron carbide content may affect the concrete strength and other properties.

  7. Study of biosorbents application on the treatment of radioactive liquid wastes with americium-241; Estudo da aplicacao de biossorventes no tratamento de rejeitos radioativos liquidos contendo americio-241

    Energy Technology Data Exchange (ETDEWEB)

    Borba, Tania Regina de

    2010-07-01

    The use of nuclear energy for many different purposes has been intensified and highlighted by the benefits that it provides. Medical diagnosis and therapy, agriculture, industry and electricity generation are examples of its application. However, nuclear energy generates radioactive wastes that require suitable treatment ensuring life and environmental safety. Biosorption and bioaccumulation represent an emergent alternative for the treatment of radioactive liquid wastes, providing volume reduction and physical state change. This work aimed to study biosorbents for the treatment of radioactive liquid wastes contaminated with americium-241 in order to reduce the volume and change the physical state from liquid to solid. The biosorbents evaluated were Saccharomyces cerevisiae immobilized in calcium alginate beads, inactivated and free cells of Saccharomyces cerevisiae, calcium alginate beads, Bacillus subtilis, Cupriavidus metallidurans and Ochrobactrum anthropi. The results were quite satisfactory, achieving 100% in some cases. The technique presented in this work may be useful and viable for implementing at the Waste Management Laboratory of IPEN - CNEN/SP in short term, since it is an easy and low cost method. (author)

  8. Human bones obtained from routine joint replacement surgery as a tool for studies of plutonium, americium and {sup 90}Sr body-burden in general public

    Energy Technology Data Exchange (ETDEWEB)

    Mietelski, Jerzy W., E-mail: jerzy.mietelski@ifj.edu.pl [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland); Golec, Edward B. [Traumatology and Orthopaedic Clinic, 5th Military Clinical Hospital and Polyclinic, Independent Public Healthcare Facility, Wroclawska 1-3, 30-901 Cracow (Poland); Orthopaedic Rehabilitation Department, Chair of Clinical Rehabilitation, Faculty of Motor of the Bronislaw Czech' s Academy of Physical Education, Cracow (Poland); Department of Physical Therapy Basics, Faculty of Physical Therapy, Administration College, Bielsko-Biala (Poland); Tomankiewicz, Ewa [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland); Golec, Joanna [Orthopaedic Rehabilitation Department, Chair of Clinical Rehabilitation, Faculty of Motor of the Bronislaw Czech' s Academy of Physical Education, Cracow (Poland); Physical Therapy Department, Institute of Physical Therapy, Faculty of Heath Science, Jagiellonian University, Medical College, Cracow (Poland); Nowak, Sebastian [Traumatology and Orthopaedic Clinic, 5th Military Clinical Hospital and Polyclinic, Independent Public Healthcare Facility, Wroclawska 1-3, 30-901 Cracow (Poland); Orthopaedic Rehabilitation Department, Chair of Clinical Rehabilitation, Faculty of Motor of the Bronislaw Czech' s Academy of Physical Education, Cracow (Poland); Szczygiel, Elzbieta [Physical Therapy Department, Institute of Physical Therapy, Faculty of Heath Science, Jagiellonian University, Medical College, Cracow (Poland); Brudecki, Kamil [Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, Radzikowskiego 152, 31-342 Cracow (Poland)

    2011-06-15

    The paper presents a new sampling method for studying in-body radioactive contamination by bone-seeking radionuclides such as {sup 90}Sr, {sup 239+240}Pu, {sup 238}Pu, {sup 241}Am and selected gamma-emitters, in human bones. The presented results were obtained for samples retrieved from routine surgeries, namely knee or hip joints replacements with implants, performed on individuals from Southern Poland. This allowed to collect representative sets of general public samples. The applied analytical radiochemical procedure for bone matrix is described in details. Due to low concentrations of {sup 238}Pu the ratio of Pu isotopes which might be used for Pu source identification is obtained only as upper limits other then global fallout (for example Chernobyl) origin of Pu. Calculated concentrations of radioisotopes are comparable to the existing data from post-mortem studies on human bones retrieved from autopsy or exhumations. Human bones removed during knee or hip joint surgery provide a simple and ethical way for obtaining samples for plutonium, americium and {sup 90}Sr in-body contamination studies in general public. - Highlights: > Surgery for joint replacement as novel sampling method for studying in-body radioactive contamination. > Proposed way of sampling is not causing ethic doubts. > It is a convenient way of collecting human bone samples from global population. > The applied analytical radiochemical procedure for bone matrix is described in details. > The opposite patient age correlations trends were found for 90Sr (negative) and Pu, Am (positive).

  9. The construction of TRIGA-TRAP and direct high-precision Penning trap mass measurements on rare-earth elements and americium

    Energy Technology Data Exchange (ETDEWEB)

    Ketelaer, Jens

    2010-06-14

    The construction of TRIGA-TRAP and direct high-precision Penning trap mass measurements on rare-earth elements and americium: Nuclear masses are an important quantity to study nuclear structure since they reflect the sum of all nucleonic interactions. Many experimental possibilities exist to precisely measure masses, out of which the Penning trap is the tool to reach the highest precision. Moreover, absolute mass measurements can be performed using carbon, the atomic-mass standard, as a reference. The new double-Penning trap mass spectrometer TRIGA-TRAP has been installed and commissioned within this thesis work, which is the very first experimental setup of this kind located at a nuclear reactor. New technical developments have been carried out such as a reliable non-resonant laser ablation ion source for the production of carbon cluster ions and are still continued, like a non-destructive ion detection technique for single-ion measurements. Neutron-rich fission products will be available by the reactor that are important for nuclear astrophysics, especially the r-process. Prior to the on-line coupling to the reactor, TRIGA-TRAP already performed off-line mass measurements on stable and long-lived isotopes and will continue this program. The main focus within this thesis was on certain rare-earth nuclides in the well-established region of deformation around N {proportional_to} 90. Another field of interest are mass measurements on actinoids to test mass models and to provide direct links to the mass standard. Within this thesis, the mass of {sup 241}Am could be measured directly for the first time. (orig.)

  10. Analysis of cascade impactor and EPA method 29 data from the americium/curium pilot melter system

    Energy Technology Data Exchange (ETDEWEB)

    Zamecnik, J.R.

    1997-11-01

    The offgas system of the Am/Cm pilot melter at TNX was characterized by measuring the particulate evolution using a cascade impactor and EPA Method 29. This sampling work was performed by John Harden of the Clemson Environmental Technologies Laboratory, under SCUREF Task SC0056. Elemental analyses were performed by the SRTC Mobile Laboratory.Operation of the Am/Cm melter with B2000 frit has resulted in deposition of PbO and boron compounds in the offgas system that has contributed to pluggage of the High Efficiency Mist Eliminator (HEME). Sampling of the offgas system was performed to quantify the amount of particulate in the offgas system under several sets of conditions. Particulate concentration and particle size distribution were measured just downstream of the melter pressure control air addition port and at the HEME inlet. At both locations, the particulate was measured with and without steam to the film cooler while the melter was idled at about 1450 degrees Celsius. Additional determinations were made at the melter location during feeding and during idling at 1150 degrees Celsius rather than 1450 degrees Celsius (both with no steam to the film cooler). Deposition of particulates upstream of the melter sample point may have, and most likely did occur in each run, so the particulate concentrations measured do no necessarily reflect the total particulate emission at the melt surface. However, the data may be used in a relative sense to judge the system performance.

  11. [Food additives and healthiness].

    Science.gov (United States)

    Heinonen, Marina

    2014-01-01

    Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects.

  12. EURADOS action for determination of americium in skull measures in vivo and Monte Carlo simulation; Accion EURADOS para la determinacion de americio en craneo mediante medidas in-vivo y simulacion Monte Carlo

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Ponte, M. A.; Navarro Amaro, J. F.; Perez Lopez, B.; Navarro Bravo, T.; Nogueira, P.; Vrba, T.

    2013-07-01

    From the Group of WG7 internal dosimetry of the EURADOS Organization (European Radiation Dosimetry group, e.V.) which It coordinates CIEMAT, international action for the vivo measurement of americium has been conducted in three mannequins type skull with detectors of Germanium by gamma spectrometry and simulation by Monte Carlo methods. Such action has been raised as two separate exercises, with the participation of institutions in Europe, America and Asia. Other actions similar precede this vivo intercomparison of measurement and modeling Monte Carlo1. The preliminary results and associated findings are presented in this work. The laboratory of the body radioactivity (CRC) of service counter of dosimetry staff internal (DPI) of the CIEMAT, it has been one of the participants in vivo measures exercise. On the other hand part, the Group of numerical dosimetry of CIEMAT is participant of the Monte Carlo2 simulation exercise. (Author)

  13. Additives in yoghurt production

    Directory of Open Access Journals (Sweden)

    Milna Tudor

    2008-02-01

    Full Text Available In yoghurt production, mainly because of sensory characteristics, different types of additives are used. Each group, and also each substance from the same group has different characteristics and properties. For that reason, for improvement of yoghurt sensory characteristics apart from addition selection, the quantity of the additive is very important. The same substance added in optimal amount improves yoghurt sensory attributes, but too small or too big addition can reduce yoghurt sensory attributes. In this paper, characteristics and properties of mostly used additives in yoghurt production are described; skimmed milk powder, whey powder, concentrated whey powder, sugars and artificial sweeteners, fruits, stabilizers, casein powder, inulin and vitamins. Also the impact of each additive on sensory and physical properties of yoghurt, syneresis and viscosity, are described, depending on used amount added in yoghurt production.

  14. Wire + Arc Additive Manufacturing

    OpenAIRE

    Williams, Stewart W.; Martina, Filomeno; Addison, Adrian C.; Ding, Jialuo; Pardal, Goncalo; Colegrove, Paul A.

    2016-01-01

    Depositing large components (>10 kg) in titanium, aluminium, steel and other metals is possible using Wire + Arc Additive Manufacturing. This technology adopts arc welding tools and wire as feedstock for additive manufacturing purposes. High deposition rates, low material and equipment costs, and good structural integrity make Wire+Arc Additive Manufacturing a suitable candidate for replacing the current method of manufacturing from solid billets or large forgings, especially with regards to ...

  15. Americium behaviour in plastic vessels

    Energy Technology Data Exchange (ETDEWEB)

    Legarda, F.; Herranz, M. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R., E-mail: raquel.idoeta@ehu.e [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain); Abelairas, A. [Departamento de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria de Bilbao, Universidad del Pais Vasco (UPV/EHU), Alameda de Urquijo s/n, 48013 Bilbao (Spain)

    2010-07-15

    The adsorption of {sup 241}Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of {sup 241}Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of {sup 241}Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification.

  16. Polylactides in additive biomanufacturing.

    Science.gov (United States)

    Poh, Patrina S P; Chhaya, Mohit P; Wunner, Felix M; De-Juan-Pardo, Elena M; Schilling, Arndt F; Schantz, Jan-Thorsten; van Griensven, Martijn; Hutmacher, Dietmar W

    2016-12-15

    New advanced manufacturing technologies under the alias of additive biomanufacturing allow the design and fabrication of a range of products from pre-operative models, cutting guides and medical devices to scaffolds. The process of printing in 3 dimensions of cells, extracellular matrix (ECM) and biomaterials (bioinks, powders, etc.) to generate in vitro and/or in vivo tissue analogue structures has been termed bioprinting. To further advance in additive biomanufacturing, there are many aspects that we can learn from the wider additive manufacturing (AM) industry, which have progressed tremendously since its introduction into the manufacturing sector. First, this review gives an overview of additive manufacturing and both industry and academia efforts in addressing specific challenges in the AM technologies to drive toward AM-enabled industrial revolution. After which, considerations of poly(lactides) as a biomaterial in additive biomanufacturing are discussed. Challenges in wider additive biomanufacturing field are discussed in terms of (a) biomaterials; (b) computer-aided design, engineering and manufacturing; (c) AM and additive biomanufacturing printers hardware; and (d) system integration. Finally, the outlook for additive biomanufacturing was discussed.

  17. Additive Gaussian Processes

    CERN Document Server

    Duvenaud, David; Rasmussen, Carl Edward

    2011-01-01

    We introduce a Gaussian process model of functions which are additive. An additive function is one which decomposes into a sum of low-dimensional functions, each depending on only a subset of the input variables. Additive GPs generalize both Generalized Additive Models, and the standard GP models which use squared-exponential kernels. Hyperparameter learning in this model can be seen as Bayesian Hierarchical Kernel Learning (HKL). We introduce an expressive but tractable parameterization of the kernel function, which allows efficient evaluation of all input interaction terms, whose number is exponential in the input dimension. The additional structure discoverable by this model results in increased interpretability, as well as state-of-the-art predictive power in regression tasks.

  18. Additive and polynomial representations

    CERN Document Server

    Krantz, David H; Suppes, Patrick

    1971-01-01

    Additive and Polynomial Representations deals with major representation theorems in which the qualitative structure is reflected as some polynomial function of one or more numerical functions defined on the basic entities. Examples are additive expressions of a single measure (such as the probability of disjoint events being the sum of their probabilities), and additive expressions of two measures (such as the logarithm of momentum being the sum of log mass and log velocity terms). The book describes the three basic procedures of fundamental measurement as the mathematical pivot, as the utiliz

  19. Groups – Additive Notation

    Directory of Open Access Journals (Sweden)

    Coghetto Roland

    2015-06-01

    Full Text Available We translate the articles covering group theory already available in the Mizar Mathematical Library from multiplicative into additive notation. We adapt the works of Wojciech A. Trybulec [41, 42, 43] and Artur Korniłowicz [25].

  20. Food Additives and Hyperkinesis

    Science.gov (United States)

    Wender, Ester H.

    1977-01-01

    The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

  1. Additively Manufactured Propulsion System

    OpenAIRE

    Dushku, Matthew; Mueller, Paul

    2012-01-01

    New high-performance, carbon-fiber reinforced polymer material allows additive manufacturing to produce pressure vessels capable of high pressures (thousands of pounds per square inch). This advancement in turn allows integral hybrid propulsion which is revolutionary for both CubeSats and additively-manufactured spacecraft. Hybrid propulsion offers simplicity as compared to bipropellant liquid propulsion, significantly better safety compared to solid or monopropellant hydrazine propulsion, an...

  2. Additives for the Axe

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    On May 1,China will begin to ban the production and use of two food additives commonly used to "bleach" flour,benzoyl peroxide and calcium peroxide.The decision was made after 10 years of wrangling between the policy makers,manufacturers,scientists and consumers.The Ministry of Health said in a statement it was applying the ban in response to consumers’ concerns about chemical substances in food,and technical improvements that had made the two additives unnecessary in flour processing.Minister of Health Chen Zhu has also said

  3. Alternative additives; Alternative additiver

    Energy Technology Data Exchange (ETDEWEB)

    2007-08-15

    In this project a number of industrial and agricultural waste products have been characterised and evaluated in terms of alkali-getter performance. The intended use is for biomass-fired power stations aiming at reducing corrosion or slagging related problems. The following products have been obtained, characterised and evaluated: 1) Brewery draff 2) Danish de-gassed manure 3) Paper sludge 4) Moulding sand 5) Spent bleaching earth 6) Anorthosite 7) Sand 8) Clay-sludge. Most of the above alternative additive candidates are deemed unsuitable due to insufficient chemical effect and/or expensive requirements for pre-treatment (such as drying and transportation). 3 products were selected for full-scale testing: de-gassed manure, spent bleaching earth and clay slugde. The full scale tests were undertaken at the biomass-fired power stations in Koege, Slagelse and Ensted. Spent bleaching earth (SBE) and clay sludge were the only tested additive candidates that had a proven ability to react with KCl, to thereby reduce Cl-concentrations in deposits, and reduce the deposit flux to superheater tubes. Their performance was shown to nearly as good as commercial additives. De-gassed manure, however, did not evaluate positively due to inhibiting effects of Ca in the manure. Furthermore, de-gassed manure has a high concentration of heavy metals, which imposes a financial burden with regard to proper disposal of the ash by-products. Clay-sludge is a wet clay slurring, and drying and transportation of this product entails substantial costs. Spent bleaching does not require much pre-treatment and is therefore the most promising alternative additive. On the other hand, bleaching earth contains residual plant oil which means that a range of legislation relating to waste combustion comes into play. Not least a waste combustion fee of 330 DKK/tonne. For all alternative (and commercial) additives disposal costs of the increase ash by-products represents a significant cost. This is

  4. From additivity to synergism

    DEFF Research Database (Denmark)

    Ritz, Christian; Streibig, Jens Carl

    2014-01-01

    Interest in synergistic or antagonistic effects through mixture experiments has grown immensely over the past two decades, not the least within in pharmacology and toxicology. Several definitions of reference models exist; one commonly used reference model is concentration or dose addition, which...... assumes compounds, when administrated simultaneously, do not interfere with each other at the site of action. We focus on statistical modelling that allows evaluation of dose addition. We will describe several statistical approaches that are suitable for analysis mixture data where synergistic...... or antagonistic effects may be present. The statistical models are defined and explained and some of the approaches exemplified. Code in open-source software is provided....

  5. Fabrication of targets for transmutation of americium : synthesis of inertial matrix by sol-gel method. Procedure study on the infiltration of a radioactive solutions; Fabricacion de blancos para la transmutacion de americio: sintesis de matrices inertes por el metodo sol-gel. Estudio del procedimiento de infiltracion de disoluciones radiactivas

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Carretero, A. [Universidad Complutense de Madrid (Spain)

    2002-07-01

    made. In addition a new and unexpected phase formed by the reaction of americium with spinel during the high temperature synthesis process has been identified. This new phase could provide a unique menas to stabilise Am in one particular oxidation state. (Author)

  6. Biobased lubricant additives

    Science.gov (United States)

    Fully biobased lubricants are those formulated using all biobased ingredients, i.e. biobased base oils and biobased additives. Such formulations provide the maximum environmental, safety, and economic benefits expected from a biobased product. Currently, there are a number of biobased base oils that...

  7. Advances in Additive Manufacturing

    Science.gov (United States)

    2016-07-14

    burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching ...Society for Machinery Failure Prevention Technology conference in Dayton, OH, on 23–26 May 2016. These 6 briefs were presented in the Additive...manufacturing (AM) at the 2016 conference in Dayton, Ohio, on May 24th, 2016. The presentations included work being performed within the Department of Defense

  8. Selectivity of bis-triazinyl bipyridine ligands for americium(III) in Am/Eu separation by solvent extraction. Part 1. Quantum mechanical study on the structures of BTBP complexes and on the energy of the separation.

    Science.gov (United States)

    Narbutt, Jerzy; Oziminski, Wojciech P

    2012-12-21

    Theoretical studies were carried out on two pairs of americium and europium complexes formed by tetra-N-dentate lipophilic BTBP ligands, neutral [ML(NO(3))(3)] and cationic [ML(2)](3+) where M = Am(III) or Eu(III), and L = 6,6'-bis-(5,6-diethyl-1,2,4-triazin-3-yl)-2,2'-bipyridine (C2-BTBP). Molecular structures of the complexes have been optimized at the B3LYP/6-31G(d) level and total energies of the complexes in various media were estimated using single point calculations performed at the B3LYP/6-311G(d,p) and MP2/6-311G(d,p) levels of theory. In the calculations americium and europium ions were treated using pseudo-relativistic Stuttgart-Dresden effective core potentials and the accompanying basis sets. Selectivity in solvent extraction separation of two metal ions is a co-operative function of contributions from all extractable metal complexes, which depend on physico-chemical properties of each individual complex and on its relative amount in the system. Semi-quantitative analysis of BTBP selectivity in the Am/Eu separation process, based on the contributions from the two pairs of Am(III) and Eu(III) complexes, has been carried out. To calculate the energy of Am/Eu separation, a model of the extraction process was used, consisting of complex formation in water and transfer of the formed complex to the organic phase. Under the assumptions discussed in the paper, this simple two-step model results in reliable values of the calculated differences in the energy changes for each pair of the Am/Eu complexes in both steps of the process. The greater thermodynamic stability (in water) of the Am-BTBP complexes, as compared with the analogous Eu species, caused by greater covalency of the Am-N than Eu-N bonds, is most likely the main reason for BTBP selectivity in the separation of the two metal ions. The other potential reason, i.e. differences in lipophilic properties of the analogous complexes of Am and Eu, is less important with regard to this selectivity.

  9. Perspectives on Additive Manufacturing

    Science.gov (United States)

    Bourell, David L.

    2016-07-01

    Additive manufacturing (AM) has skyrocketed in visibility commercially and in the public sector. This article describes the development of this field from early layered manufacturing approaches of photosculpture, topography, and material deposition. Certain precursors to modern AM processes are also briefly described. The growth of the field over the last 30 years is presented. Included is the standard delineation of AM technologies into seven broad categories. The economics of AM part generation is considered, and the impacts of the economics on application sectors are described. On the basis of current trends, the future outlook will include a convergence of AM fabricators, mass-produced AM fabricators, enabling of topology optimization designs, and specialization in the AM legal arena. Long-term developments with huge impact are organ printing and volume-based printing.

  10. Sarks as additional fermions

    Science.gov (United States)

    Agrawal, Jyoti; Frampton, Paul H.; Jack Ng, Y.; Nishino, Hitoshi; Yasuda, Osamu

    1991-03-01

    An extension of the standard model is proposed. The gauge group is SU(2) X ⊗ SU(3) C ⊗ SU(2) S ⊗ U(1) Q, where all gauge symmetries are unbroken. The colour and electric charge are combined with SU(2) S which becomes strongly coupled at approximately 500 GeV and binds preons to form fermionic and vector bound states. The usual quarks and leptons are singlets under SU(2) X but additional fermions, called sarks. transform under it and the electroweak group. The present model explains why no more than three light quark-lepton families can exist. Neutral sark baryons, called narks, are candidates for the cosmological dark matter having the characteristics designed for WIMPS. Further phenomenological implications of sarks are analyzed i including electron-positron annihilation. Z 0 decay, flavor-changing neutral currents. baryon-number non-conservation, sarkonium and the neutron electric dipole moment.

  11. Use of radioanalytical methods for determination of uranium, neptunium, plutonium, americium and curium isotopes in radioactive wastes; Utilizacao de metodos radioanaliticos para a determinacao de isotopos de uranio, plutonio, americio e curio em rejeitos radioativos

    Energy Technology Data Exchange (ETDEWEB)

    Geraldo, Bianca

    2012-07-01

    Activated charcoal is a common type of radioactive waste that contains high concentrations of fission and activation products. The management of this waste includes its characterization aiming the determination and quantification of the specific radionuclides including those known as Difficult-to-Measure Radionuclides (RDM). The analysis of the RDM's generally involves complex radiochemical analysis for purification and separation of the radionuclides, which are expensive and time-consuming. The objective of this work was to define a methodology for sequential analysis of the isotopes of uranium, neptunium, plutonium, americium and curium present in a type of radioactive waste, evaluating chemical yield, analysis of time spent, amount of secondary waste generated and cost. Three methodologies were compared and validated that employ ion exchange (TI + EC), extraction chromatography (EC) and extraction with polymers (ECP). The waste chosen was the activated charcoal from the purification system of primary circuit water cooling the reactor IEA-R1. The charcoal samples were dissolved by acid digestion followed by purification and separation of isotopes with ion exchange resins, extraction and chromatographic extraction polymers. Isotopes were analyzed on an alpha spectrometer, equipped with surface barrier detectors. The chemical yields were satisfactory for the methods TI + EC and EC. ECP method was comparable with those methods only for uranium. Statistical analysis as well the analysis of time spent, amount of secondary waste generated and cost revealed that EC method is the most effective for identifying and quantifying U, Np, Pu, Am and Cm present in charcoal. (author)

  12. The Additive Hazard Mixing Models

    Institute of Scientific and Technical Information of China (English)

    Ping LI; Xiao-liang LING

    2012-01-01

    This paper is concerned with the aging and dependence properties in the additive hazard mixing models including some stochastic comparisons.Further,some useful bounds of reliability functions in additive hazard mixing models are obtained.

  13. ADDITIVES USED TO OBTAIN FOOD

    Directory of Open Access Journals (Sweden)

    Dorina Ardelean

    2012-01-01

    Full Text Available Use of food additives in food is determined by the growth of contemporary food needs of the world population. Additives used in food, both natural and artificial ones, contribute to: improving the organoleptic characteristics and to preserve the food longer, but we must not forget that all these additives should not be found naturally in food products. Some of these additives are not harmful and human pests in small quantities, but others may have harmful effects on health.

  14. Detergent Additive for Lubricating Oils,

    Science.gov (United States)

    The Russian patent pertains to a method of producing additives for lubricating oils . A method is known for producing an antiwear additive for... lubricating oils by processing phenols with phosphorus oxychloride, phosphoric acid esters are obtained. In order to give the additive detergent properties

  15. Additive interaction in survival analysis

    DEFF Research Database (Denmark)

    Rod, Naja Hulvej; Lange, Theis; Andersen, Ingelise

    2012-01-01

    is the relevant measure of interest. Multiplicative survival models, such as the Cox proportional hazards model, are often used to estimate the association between exposure and risk of disease in prospective studies. In Cox models, deviations from additivity have usually been assessed by surrogate measures...... of additive interaction derived from multiplicative models-an approach that is both counter-intuitive and sometimes invalid. This paper presents a straightforward and intuitive way of assessing deviation from additivity of effects in survival analysis by use of the additive hazards model. The model directly...... estimates the absolute size of the deviation from additivity and provides confidence intervals. In addition, the model can accommodate both continuous and categorical exposures and models both exposures and potential confounders on the same underlying scale. To illustrate the approach, we present...

  16. Determination of Neptunium, Americium and Curium in Spent Nuclear Fuel Samples by Alpha Spectrometry Using {sup 239}Np and {sup 243}Am as a Spike and a Tracer

    Energy Technology Data Exchange (ETDEWEB)

    Jeo, Kih-Soo; Song, Byung-Chul; Kim, Young-Bok; Han, Sun-Ho; Jeon, Young-Shin; Jung, Euo-Chang; Jee, Kwang-Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2007-07-01

    Determination of actinide elements and fission products in spent nuclear fuels is of importance for a burnup determination and source term evaluation. Especially, the amounts of uranium and plutonium isotopes are used for the evaluation of a burnup credit in spent nuclear fuels. Additionally, other actinides such as Np, Am and Cm in spent nuclear fuel samples is also required for the purposes mentioned above. In this study, {sup 237}Np, {sup 241}Am and {sup 244}Cm were determined by an alpha spectrometry for the source term data for high burnup spent nuclear fuels ranging from 37 to 62.9 GWD/MtU as a burnup. Generally, mass spectrometry has been known as the most powerful method for isotope determinations such as high concentrations of uranium and plutonium. However, in the case of minor actinides such as Np, Am and Cm, alpha spectrometry would be recommended instead. Determination of the transuranic elements in spent nuclear fuel samples is different from that for environmental samples because the amount of each nuclide in the spent fuel samples is higher and the relative ratios between each nuclide are also different from those for environmental samples. So, it is important to select an appropriate tracer and an optimum sample size depending on the nuclides and analytical method. In this study {sup 237}Np was determined by an isotope dilution alpha(gamma) spectrometry using {sup 239}Np as a spike, and {sup 241}Am and curium isotopes were determined by alpha spectrometry using {sup 243}Am as a tracer. The content of each nuclide was compared with that by the Origen-2 code.

  17. Color Addition and Subtraction Apps

    Science.gov (United States)

    Ruiz, Frances; Ruiz, Michael J.

    2015-01-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step…

  18. Calcium addition in straw gasification

    DEFF Research Database (Denmark)

    Risnes, H.; Fjellerup, Jan Søren; Henriksen, Ulrik Birk

    2003-01-01

    The present work focuses on the influence of calcium addition in gasification. The inorganic¿organic element interaction as well as the detailed inorganic¿inorganic elements interaction has been studied. The effect of calcium addition as calcium sugar/molasses solutions to straw significantly...

  19. Additive Effects on Asymmetric Catalysis.

    Science.gov (United States)

    Hong, Liang; Sun, Wangsheng; Yang, Dongxu; Li, Guofeng; Wang, Rui

    2016-03-23

    This review highlights a number of additives that can be used to make asymmetric reactions perfect. Without changing other reaction conditions, simply adding additives can lead to improved asymmetric catalysis, such as reduced reaction time, improved yield, or/and increased selectivity.

  20. Density measures and additive property

    OpenAIRE

    Kunisada, Ryoichi

    2015-01-01

    We deal with finitely additive measures defined on all subsets of natural numbers which extend the asymptotic density (density measures). We consider a class of density measures which are constructed from free ultrafilters on natural numbers and study a certain additivity property of such density measures.

  1. Additional disulfide bonds in insulin

    DEFF Research Database (Denmark)

    Vinther, Tine N; Pettersson, Ingrid; Huus, Kasper

    2015-01-01

    -chain is flexible and can adapt multiple conformations. We examined how well disulfide bond predictions algorithms could identify disulfide bonds in this region of insulin. In order to identify stable insulin analogues with additional disulfide bonds, which could be expressed, the Cβ cut-off distance had...... in comparison to analogues with additional disulfide bonds that were more difficult to predict. In contrast, addition of the fourth disulfide bond rendered all analogues resistant to fibrillation under stress conditions and all stable analogues bound to the insulin receptor with picomolar affinities. Thus...

  2. Topology Optimization for Additive Manufacturing

    DEFF Research Database (Denmark)

    Clausen, Anders

    This PhD thesis deals with the combination of topology optimization and additive man-ufacturing (AM, also known as 3D-printing). In addition to my own works, the thesis contains a broader review and assessment of the literature within the field. The thesis first presents a classification...... of the various AM technologies, a review of relevant manufacturing materials, the properties of these materials in the additively manufactured part, as well as manufacturing constraints with a potential for design optimization. Subsequently, specific topology optimization formulations relevant for the most im...... for scalable manufacturing. In relation to interface problems it is shown how a flexible void area may be included into a standard minimum compliance problem by employing an additional design variable field and a sensitivity filter. Furthermore, it is shown how the design of coated structures may be modeled...

  3. Prevalence of Food Additive Intolerance

    DEFF Research Database (Denmark)

    Madsen, Charlotte Bernhard

    1994-01-01

    1 The existing prevalence estimates of food additive intolerance(1-4) are being reviewed. 2 In the EEC report the estimated frequency of food additive intolerance is 0.03% to 0.15% based on data from patient groups. 3 The British population study results in a prevalence estimate of 0.......026%. The challenged population is 81 children and adults with a history of reproducible clinical symptoms after ingestion of food additives. 4 In the Danish population study a prevalence of 1-2% is found in children age 5-16. In this study a total of 606 children mainly with atopic disease have been challenged. 5...... The prevalence estimates vary with a factor 100. As the results vary so do the study populations. 6 If the different study populations are accounted for, a common conclusion can be drawn: Food additive intolerance is found in adults with atopic symptoms from the respiratory tract and skin. The prevalence...

  4. Radiation Therapy: Additional Treatment Options

    Science.gov (United States)

    ... Cancer Upper GI Cancers Search x FIND A RADIATION ONCOLOGIST CLOSE TREATMENT TYPES Home / Treatment Types / Additional ... novel targeted therapies can act as radiosensitizers. Systemic Radiation Therapy Certain cancers may be treated with radioactive ...

  5. Adverse reactions to drug additives.

    Science.gov (United States)

    Simon, R A

    1984-10-01

    There is a long list of additives used by the pharmaceutical industry. Most of the agents used have not been implicated in hypersensitivity reactions. Among those that have, only reactions to parabens and sulfites have been well established. Parabens have been shown to be responsible for rare immunoglobulin E-mediated reactions that occur after the use of local anesthetics. Sulfites, which are present in many drugs, including agents commonly used to treat asthma, have been shown to provoke severe asthmatic attacks in sensitive individuals. Recent studies indicate that additives do not play a significant role in "hyperactivity." The role of additives in urticaria is not well established and therefore the incidence of adverse reactions in this patient population is simply not known. In double-blind, placebo-controlled studies, reactions to tartrazine or additives other than sulfites, if they occur at all, are indeed quite rare for the asthmatic population, even for the aspirin-sensitive subpopulation.

  6. Addition on a Quantum Computer

    CERN Document Server

    Draper, Thomas G

    2000-01-01

    A new method for computing sums on a quantum computer is introduced. This technique uses the quantum Fourier transform and reduces the number of qubits necessary for addition by removing the need for temporary carry bits. This approach also allows the addition of a classical number to a quantum superposition without encoding the classical number in the quantum register. This method also allows for massive parallelization in its execution.

  7. Food additives and preschool children.

    Science.gov (United States)

    Martyn, Danika M; McNulty, Breige A; Nugent, Anne P; Gibney, Michael J

    2013-02-01

    Food additives have been used throughout history to perform specific functions in foods. A comprehensive framework of legislation is in place within Europe to control the use of additives in the food supply and ensure they pose no risk to human health. Further to this, exposure assessments are regularly carried out to monitor population intakes and verify that intakes are not above acceptable levels (acceptable daily intakes). Young children may have a higher dietary exposure to chemicals than adults due to a combination of rapid growth rates and distinct food intake patterns. For this reason, exposure assessments are particularly important in this age group. The paper will review the use of additives and exposure assessment methods and examine factors that affect dietary exposure by young children. One of the most widely investigated unfavourable health effects associated with food additive intake in preschool-aged children are suggested adverse behavioural effects. Research that has examined this relationship has reported a variety of responses, with many noting an increase in hyperactivity as reported by parents but not when assessed using objective examiners. This review has examined the experimental approaches used in such studies and suggests that efforts are needed to standardise objective methods of measuring behaviour in preschool children. Further to this, a more holistic approach to examining food additive intakes by preschool children is advisable, where overall exposure is considered rather than focusing solely on behavioural effects and possibly examining intakes of food additives other than food colours.

  8. Clinical effects of sulphite additives.

    Science.gov (United States)

    Vally, H; Misso, N L A; Madan, V

    2009-11-01

    Sulphites are widely used as preservative and antioxidant additives in the food and pharmaceutical industries. Topical, oral or parenteral exposure to sulphites has been reported to induce a range of adverse clinical effects in sensitive individuals, ranging from dermatitis, urticaria, flushing, hypotension, abdominal pain and diarrhoea to life-threatening anaphylactic and asthmatic reactions. Exposure to the sulphites arises mainly from the consumption of foods and drinks that contain these additives; however, exposure may also occur through the use of pharmaceutical products, as well as in occupational settings. While contact sensitivity to sulphite additives in topical medications is increasingly being recognized, skin reactions also occur after ingestion of or parenteral exposure to sulphites. Most studies report a 3-10% prevalence of sulphite sensitivity among asthmatic subjects following ingestion of these additives. However, the severity of these reactions varies, and steroid-dependent asthmatics, those with marked airway hyperresponsiveness, and children with chronic asthma, appear to be at greater risk. In addition to episodic and acute symptoms, sulphites may also contribute to chronic skin and respiratory symptoms. To date, the mechanisms underlying sulphite sensitivity remain unclear, although a number of potential mechanisms have been proposed. Physicians should be aware of the range of clinical manifestations of sulphite sensitivity, as well as the potential sources of exposure. Minor modifications to diet or behaviour lead to excellent clinical outcomes for sulphite-sensitive individuals.

  9. [INVITED] Lasers in additive manufacturing

    Science.gov (United States)

    Pinkerton, Andrew J.

    2016-04-01

    Additive manufacturing is a topic of considerable ongoing interest, with forecasts predicting it to have major impact on industry in the future. This paper focusses on the current status and potential future development of the technology, with particular reference to the role of lasers within it. It begins by making clear the types and roles of lasers in the different categories of additive manufacturing. This is followed by concise reviews of the economic benefits and disadvantages of the technology, current state of the market and use of additive manufacturing in different industries. Details of these fields are referenced rather than expanded in detail. The paper continues, focusing on current indicators to the future of additive manufacturing. Barriers to its development, trends and opportunities in major industrial sectors, and wider opportunities for its development are covered. Evidence indicates that additive manufacturing may not become the dominant manufacturing technology in all industries, but represents an excellent opportunity for lasers to increase their influence in manufacturing as a whole.

  10. Evaluation of certain food additives.

    Science.gov (United States)

    2015-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, and to prepare specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of and assessment of dietary exposure to food additives, including flavouring agents. A summary follows of the Committee's evaluations of technical, toxicological and dietary exposure data for eight food additives (Benzoe tonkinensis; carrageenan; citric and fatty acid esters of glycerol; gardenia yellow; lutein esters from Tagetes erecta; octenyl succinic acid-modified gum arabic; octenyl succinic acid-modified starch; paprika extract; and pectin) and eight groups of flavouring agents (aliphatic and alicyclic hydrocarbons; aliphatic and aromatic ethers; ionones and structurally related substances; miscellaneous nitrogen-containing substances; monocyclic and bicyclic secondary alcohols, ketones and related esters; phenol and phenol derivatives; phenyl-substituted aliphatic alcohols and related aldehydes and esters; and sulfur-containing heterocyclic compounds). Specifications for the following food additives were revised: citric acid; gellan gum; polyoxyethylene (20) sorbitan monostearate; potassium aluminium silicate; and Quillaia extract (Type 2). Annexed to the report are tables summarizing the Committee's recommendations for dietary exposures to and toxicological evaluations of all of the food additives and flavouring agents considered at this meeting.

  11. Ruzsa's Constant on Additive Functions

    Institute of Scientific and Technical Information of China (English)

    Jin Hui FANG; Yong Gao CHEN

    2013-01-01

    A function f:N → R is called additive if f(mn) =f(m)+f(n) for all m,n with (m,n) =1.Let μ(x) =maxn≤x(f(n)-f(n + 1)) and v(x) =maxn≤x(f(n + 1)-f(n)).In 1979,Ruzsa proved that there exists a constant c such that for any additive function f,μ(x) ≤ cv(x2) + cf,where cf is a constant depending only on f.Denote by Raf the least such constant c.We call Raf Ruzsa's constant on additive functions.In this paper,we prove that Raf ≤ 20.

  12. Additive Manufacturing of Hybrid Circuits

    Science.gov (United States)

    Sarobol, Pylin; Cook, Adam; Clem, Paul G.; Keicher, David; Hirschfeld, Deidre; Hall, Aaron C.; Bell, Nelson S.

    2016-07-01

    There is a rising interest in developing functional electronics using additively manufactured components. Considerations in materials selection and pathways to forming hybrid circuits and devices must demonstrate useful electronic function; must enable integration; and must complement the complex shape, low cost, high volume, and high functionality of structural but generally electronically passive additively manufactured components. This article reviews several emerging technologies being used in industry and research/development to provide integration advantages of fabricating multilayer hybrid circuits or devices. First, we review a maskless, noncontact, direct write (DW) technology that excels in the deposition of metallic colloid inks for electrical interconnects. Second, we review a complementary technology, aerosol deposition (AD), which excels in the deposition of metallic and ceramic powder as consolidated, thick conformal coatings and is additionally patternable through masking. Finally, we show examples of hybrid circuits/devices integrated beyond 2-D planes, using combinations of DW or AD processes and conventional, established processes.

  13. The selective addition of water

    NARCIS (Netherlands)

    Resch, V.; Hanefeld, U.

    2014-01-01

    Water is omnipresent and essential. Yet at the same time it is a rather unreactive molecule. The direct addition of water to C[double bond, length as m-dash]C double bonds is therefore a challenge not answered convincingly. In this perspective we critically evaluate the selectivity and the applicabi

  14. Business models for additive manufacturing

    DEFF Research Database (Denmark)

    Hadar, Ronen; Bilberg, Arne; Bogers, Marcel

    2015-01-01

    Digital fabrication — including additive manufacturing (AM), rapid prototyping and 3D printing — has the potential to revolutionize the way in which products are produced and delivered to the customer. Therefore, it challenges companies to reinvent their business model — describing the logic...

  15. Additively manufactured porous tantalum implants

    NARCIS (Netherlands)

    Wauthle, Ruben; Van Der Stok, Johan; Yavari, Saber Amin; Van Humbeeck, Jan; Kruth, Jean Pierre; Zadpoor, Amir Abbas; Weinans, Harrie; Mulier, Michiel; Schrooten, Jan

    2015-01-01

    The medical device industry's interest in open porous, metallic biomaterials has increased in response to additive manufacturing techniques enabling the production of complex shapes that cannot be produced with conventional techniques. Tantalum is an important metal for medical devices because of it

  16. Protocol for ADDITION-PRO

    DEFF Research Database (Denmark)

    Johansen, Nanna Borup; Hansen, Anne-Louise Smidt; Jensen, Troels M;

    2012-01-01

    disease and microvascular diabetic complications. We also require a better understanding of the mechanisms that underlie and drive early changes in cardiometabolic physiology. The ADDITION-PRO study was designed to address these issues among individuals at different levels of diabetes risk recruited from...

  17. Delocalization and new phase in Americium: theory

    Energy Technology Data Exchange (ETDEWEB)

    Soderlind, P

    1999-04-23

    Density-functional electronic structure calculations have been used to investigate the high pressure behavior of Am. At about 80 kbar (8 GPa) calculations reveal a monoclinic phase similar to the ground state structure of plutonium ({alpha}-Pu). The experimentally suggested {alpha}-U structure is found to be substantially higher in energy. The phase transition from fcc to the low symmetry structure is shown to originate from a drastic change in the nature of the electronic structure induced by the elevated pressure. A calculated volume collapse of about 25% is associated with the transition. For the low density phase, an orbital polarization correction to the local spin density (LSD) theory was applied. Gradient terms of the electron density were included in the calculation of the exchange/correlation energy and potential, according to the generalized gradient approximation (GGA). The results are consistent with a Mott transition; the 5f electrons are delocalized and bonding on the high density side of the transition and chemically inert and non-bonding (localized) on the other. Theory compares rather well with recent experimental data which implies that electron correlation effects are reasonably modeled in our orbital polarization scheme.

  18. The proliferation potential of neptunium and americium

    Energy Technology Data Exchange (ETDEWEB)

    An, J. S.; Shin, J. S.; Kim, J. S.; Kwack, E. H.; Kim, B. K

    2000-05-01

    It is recognized that some trans-uranic elements other than plutonium, in particular Np and Am, if will be available in sufficient quantities, could be used for nuclear explosive devices. The spent fuel has been accumulating in number of nuclear power plant and operation of large scale commercial reprocessing plants. However, these materials are not covered by the definition of special fissionable material in the Agency Statute. At the time when the Statute was adopted, the availability of meaningful quantities of separated Np and Am was remote and they were not included in the definition of special fissionable material. Then, IAEA Board decided a measure for control of Np and Am on September 1999. This report contains the control method and the characteristic of Np and Am for using domestic nuclear industries, and it can be useful for understanding how to report and account of Np and Am. (author)

  19. Evaluation of neutron data for americium-241

    Energy Technology Data Exchange (ETDEWEB)

    Maslov, V.M.; Sukhovitskij, E.Sh.; Porodzinskij, Yu.V.; Klepatskij, A.B.; Morogovskij, G.B. [Radiation Physics and Chemistry Problems Inst., Minsk-Sosny (Belarus)

    1997-03-01

    The evaluation of neutron data for {sup 241}Am is made in the energy region from 10{sup -5} eV up to 20 MeV. The results of the evaluation are compiled in the ENDF/B-VI format. This work is performed under the Project Agreement CIS-03-95 with the International Science and Technology Center (Moscow). The Financing Party for the Project is Japan. The evaluation was requested by Y. Kikuchi (JAERI). (author). 60 refs.

  20. The Frontiers of Additive Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Grote, Christopher John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-03-03

    Additive manufacturing, more commonly known as 3-D printing, has become a ubiquitous tool in science for its precise control over mechanical design. For additive manufacturing to work, a 3-D structure is split into thin 2D slices, and then different physical properties, such as photo-polymerization or melting, are used to grow the sequential layers. The level of control allows not only for devices to be made with a variety of materials: e.g. plastics, metals, and quantum dots, but to also have finely controlled structures leading to other novel properties. While 3-D printing is widely used by hobbyists for making models, it also has industrial applications in structural engineering, biological tissue scaffolding, customized electric circuitry, fuel cells, security, and more.

  1. Ice cream with additional value

    OpenAIRE

    Melicharová, Barbora

    2016-01-01

    The aim of this bachelor thesis is to summarise current knowledge about production and properties of ice cream with an additional value. Nowadays, incorporation of probiotics is considered as the most intensively studied possibility for functional ice cream manufacture. Their viability depends on the kind of a microorganism, for example bifidobacteria are mostly less stable than lactobacilli in ice cream matrix. Lactobacillus acidophilus AB518, AK414, Lactobacillus agilis AA1773, AC1888 and L...

  2. Tweaking Synchronisation by Link Addition

    CERN Document Server

    Schultz, Paul; Eroglu, Deniz; Stemler, Thomas; Ávila, G Marcelo Ramírez; Rodrigues, Francisco A; Kurths, Jürgen

    2016-01-01

    Natural and man-made networks often possess locally tree-like sub-structures. Taking such tree networks as our starting point, we show how the addition of links changes the synchronization properties of the network. We focus on two different methods of link addition. The first method adds single links that create cycles of a well-defined length. Following a topological approach we introduce cycles of varying length and analyze how this feature, as well as the position in the network, alters the synchronous behaviour. We show that in particular short cycles can lead to a maximum change of the Laplacian's eigenvalue spectrum, dictating the synchronization properties of such networks. The second method connects a certain proportion of the initially unconnected nodes. We simulate dynamical systems on these network topologies, with the nodes' local dynamics being either a discrete or continuous. Here our main result is that a certain amount of additional links, with the relative position in the network being cruci...

  3. Reversible Oxidative Addition at Carbon.

    Science.gov (United States)

    Eichhorn, Antonius F; Fuchs, Sonja; Flock, Marco; Marder, Todd B; Radius, Udo

    2017-04-07

    The reactivity of N-heterocyclic carbenes (NHCs) and cyclic alkyl amino carbenes (cAACs) with arylboronate esters is reported. The reaction with NHCs leads to the reversible formation of thermally stable Lewis acid/base adducts Ar-B(OR)2 ⋅NHC (Add1-Add6). Addition of cAAC(Me) to the catecholboronate esters 4-R-C6 H4 -Bcat (R=Me, OMe) also afforded the adducts 4-R-C6 H4 Bcat⋅cAAC(Me) (Add7, R=Me and Add8, R=OMe), which react further at room temperature to give the cAAC(Me) ring-expanded products RER1 and RER2. The boronate esters Ar-B(OR)2 of pinacol, neopentylglycol, and ethyleneglycol react with cAAC at RT via reversible B-C oxidative addition to the carbene carbon atom to afford cAAC(Me) (B{OR}2 )(Ar) (BCA1-BCA6). NMR studies of cAAC(Me) (Bneop)(4-Me-C6 H4 ) (BCA4) demonstrate the reversible nature of this oxidative addition process.

  4. ADDITIONAL STREET BERBASIS APP INVENTOR

    Directory of Open Access Journals (Sweden)

    Mohammad Adib Adhi Prabowo

    2013-05-01

    Full Text Available Abstrak Seiring dengan perkembangan sistem operasi android, telah banyak aplikasi yang memanfaatkan fasilitas GPS dan Google Map, seperti untuk mencari rute, mendapatkan peta, mencari lokasi tertentu pada sebuah tempat. Akan tetapi seringkali pengguna perangkat bergerak kesulitan ketika ingin mengetahui beberapa tempat dan lokasi tertentu karena belum ada fasilitas yang menyediakan informasi lokasi suatu tempat. Walaupun ada informasi lokasi pada peta biasanya informasi yang diberikan lokasi tempat berskala besar, misalnya lokasi tempat wisata atau stasiun kereta api. Pengembangan aplikasi untuk skala kecil ini akan memberikan informasi yang dipresentasikan pada google map. Selama ini belum ada yang memberikan sebuah informasi lokasi tempat penting yang berskala kecil. Misalnya informasi lokasi  tambal ban, lokasi warung makan, lokasi laundry, dan lokasi bengkel motor. Oleh karena itu kami mencoba untuk mengembangkan aplikasi additional street berbasis android via App Inventor dengan bantuan google maps. Aplikasi additional street ini dapat memberikan informasi letak objek pada peta serta memberikan informasi jalan menuju lokasi tersebut dan detail informasi lokasi tersebut serta lokasi dari pengguna aplikasi tersebut. Kata Kunci: additional street, android, google maps, app inventor, GPS

  5. Fire-Retardant Polymeric Additives

    Science.gov (United States)

    Williams, Martha K.; Smith, Trent M.

    2011-01-01

    Polyhydroxyamide (PHA) and polymethoxyamide (PMeOA) are fire-retardant (FR) thermoplastic polymers and have been found to be useful as an additive for imparting fire retardant properties to other compatible, thermoplastic polymers (including some elastomers). Examples of compatible flammable polymers include nylons, polyesters, and acrylics. Unlike most prior additives, PHA and PMeOA do not appreciably degrade the mechanical properties of the matrix polymer; indeed, in some cases, mechanical properties are enhanced. Also, unlike some prior additives, PHA and PMeOA do not decompose into large amounts of corrosive or toxic compounds during combustion and can be processed at elevated temperatures. PMeOA derivative formulations were synthesized and used as an FR additive in the fabrication of polyamide (PA) and polystyrene (PS) composites with notable reduction (>30 percent for PS) in peak heat release rates compared to the neat polymer as measured by a Cone Calorimeter (ASTM E1354). Synergistic effects were noted with nanosilica composites. These nanosilica composites had more than 50-percent reduction in peak heat release rates. In a typical application, a flammable thermoplastic, thermoplastic blend, or elastomer that one seeks to render flame-retardant is first dry-mixed with PHA or PMeOA or derivative thereof. The proportion of PHA or PMeOA or derivative in the mixture is typically chosen to lie between 1 and 20 weight percent. The dry blend can then be melt-extruded. The extruded polymer blend can further be extruded and/or molded into fibers, pipes, or any other of a variety of objects that may be required to be fire-retardant. The physical and chemical mechanisms which impart flame retardancy of the additive include inhibiting free-radical oxidation in the vapor phase, preventing vaporization of fuel (the polymer), and cooling through the formation of chemical bonds in either the vapor or the condensed phase. Under thermal stress, the cyclic hydroxyl/ methoxy

  6. Evaluation of certain food additives.

    Science.gov (United States)

    2009-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessment of intake of food additives (in particular, flavouring agents). A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives (asparaginase from Aspergillus niger expressed in A. niger, calcium lignosulfonate (40-65), ethyl lauroyl arginate, paprika extract, phospholipase C expressed in Pichia pastoris, phytosterols, phytostanols and their esters, polydimethylsiloxane, steviol glycosides and sulfites [assessment of dietary exposure]) and 10 groups of related flavouring agents (aliphatic branched-chain saturated and unsaturated alcohols, aldehydes, acids and related esters; aliphatic linear alpha,beta-unsaturated aldehydes, acids and related alcohols, acetals and esters; aliphatic secondary alcohols, ketones and related esters; alkoxy-substituted allylbenzenes present in foods and essential oils and used as flavouring agents; esters of aliphatic acyclic primary alcohols with aliphatic linear saturated carboxylic acids; furan-substituted aliphatic hydrocarbons, alcohols, aldehydes, ketones, carboxylic acids and related esters, sulfides, disulfides and ethers; miscellaneous nitrogen-containing substances; monocyclic and bicyclic secondary alcohols, ketones and related esters; hydroxy- and alkoxy-substituted benzyl derivatives; and substances structurally related to menthol). Specifications for the following food additives were revised: canthaxanthin; carob bean gum and carob bean gum (clarified); chlorophyllin copper complexes, sodium and potassium salts; Fast Green FCF; guar gum and guar gum (clarified

  7. Metal Additive Manufacturing: A Review

    Science.gov (United States)

    Frazier, William E.

    2014-06-01

    This paper reviews the state-of-the-art of an important, rapidly emerging, manufacturing technology that is alternatively called additive manufacturing (AM), direct digital manufacturing, free form fabrication, or 3D printing, etc. A broad contextual overview of metallic AM is provided. AM has the potential to revolutionize the global parts manufacturing and logistics landscape. It enables distributed manufacturing and the productions of parts-on-demand while offering the potential to reduce cost, energy consumption, and carbon footprint. This paper explores the material science, processes, and business consideration associated with achieving these performance gains. It is concluded that a paradigm shift is required in order to fully exploit AM potential.

  8. Individualized additional instruction for calculus

    Science.gov (United States)

    Takata, Ken

    2010-10-01

    College students enrolling in the calculus sequence have a wide variance in their preparation and abilities, yet they are usually taught from the same lecture. We describe another pedagogical model of Individualized Additional Instruction (IAI) that assesses each student frequently and prescribes further instruction and homework based on the student's performance. Our study compares two calculus classes, one taught with mandatory remedial IAI and the other without. The class with mandatory remedial IAI did significantly better on comprehensive multiple-choice exams, participated more frequently in classroom discussion and showed greater interest in theorem-proving and other advanced topics.

  9. The Mozart Effect: Additional Data.

    Science.gov (United States)

    Hughes, John R.

    2002-04-01

    After the review of the Mozart effect was published in this journal (Hughes JR. Epilepsy Behav 2001;2:369-417), additional data from the music of Haydn and Liszt have been analyzed that may account for the decrease in seizure activity originally reported during Mozart music. Even with these added data Mozart music continued to score significantly higher than the selections from the other six composers in one of the important characteristics of this music, namely, the repetition of the melody. However Haydn's values were second highest among Mozart, J. S. Bach, Wagner, Beethoven, Chopin, and Liszt.

  10. Neutron Characterization for Additive Manufacturing

    Science.gov (United States)

    Watkins, Thomas; Bilheux, Hassina; An, Ke; Payzant, Andrew; DeHoff, Ryan; Duty, Chad; Peter, William; Blue, Craig; Brice, Craig A.

    2013-01-01

    Oak Ridge National Laboratory (ORNL) is leveraging decades of experience in neutron characterization of advanced materials together with resources such as the Spallation Neutron Source (SNS) and the High Flux Isotope Reactor (HFIR) shown in Fig. 1 to solve challenging problems in additive manufacturing (AM). Additive manufacturing, or three-dimensional (3-D) printing, is a rapidly maturing technology wherein components are built by selectively adding feedstock material at locations specified by a computer model. The majority of these technologies use thermally driven phase change mechanisms to convert the feedstock into functioning material. As the molten material cools and solidifies, the component is subjected to significant thermal gradients, generating significant internal stresses throughout the part (Fig. 2). As layers are added, inherent residual stresses cause warping and distortions that lead to geometrical differences between the final part and the original computer generated design. This effect also limits geometries that can be fabricated using AM, such as thin-walled, high-aspect- ratio, and overhanging structures. Distortion may be minimized by intelligent toolpath planning or strategic placement of support structures, but these approaches are not well understood and often "Edisonian" in nature. Residual stresses can also impact component performance during operation. For example, in a thermally cycled environment such as a high-pressure turbine engine, residual stresses can cause components to distort unpredictably. Different thermal treatments on as-fabricated AM components have been used to minimize residual stress, but components still retain a nonhomogeneous stress state and/or demonstrate a relaxation-derived geometric distortion. Industry, federal laboratory, and university collaboration is needed to address these challenges and enable the U.S. to compete in the global market. Work is currently being conducted on AM technologies at the ORNL

  11. An Additive Manufacturing Test Artifact.

    Science.gov (United States)

    Moylan, Shawn; Slotwinski, John; Cooke, April; Jurrens, Kevin; Donmez, M Alkan

    2014-01-01

    A test artifact, intended for standardization, is proposed for the purpose of evaluating the performance of additive manufacturing (AM) systems. A thorough analysis of previously proposed AM test artifacts as well as experience with machining test artifacts have inspired the design of the proposed test artifact. This new artifact is designed to provide a characterization of the capabilities and limitations of an AM system, as well as to allow system improvement by linking specific errors measured in the test artifact to specific sources in the AM system. The proposed test artifact has been built in multiple materials using multiple AM technologies. The results of several of the builds are discussed, demonstrating how the measurement results can be used to characterize and improve a specific AM system.

  12. Dimensionless numbers in additive manufacturing

    Science.gov (United States)

    Mukherjee, T.; Manvatkar, V.; De, A.; DebRoy, T.

    2017-02-01

    The effects of many process variables and alloy properties on the structure and properties of additively manufactured parts are examined using four dimensionless numbers. The structure and properties of components made from 316 Stainless steel, Ti-6Al-4V, and Inconel 718 powders for various dimensionless heat inputs, Peclet numbers, Marangoni numbers, and Fourier numbers are studied. Temperature fields, cooling rates, solidification parameters, lack of fusion defects, and thermal strains are examined using a well-tested three-dimensional transient heat transfer and fluid flow model. The results show that lack of fusion defects in the fabricated parts can be minimized by strengthening interlayer bonding using high values of dimensionless heat input. The formation of harmful intermetallics such as laves phases in Inconel 718 can be suppressed using low heat input that results in a small molten pool, a steep temperature gradient, and a fast cooling rate. Improved interlayer bonding can be achieved at high Marangoni numbers, which results in vigorous circulation of liquid metal, larger pool dimensions, and greater depth of penetration. A high Fourier number ensures rapid cooling, low thermal distortion, and a high ratio of temperature gradient to the solidification growth rate with a greater tendency of plane front solidification.

  13. Dynamics of ultrasonic additive manufacturing.

    Science.gov (United States)

    Hehr, Adam; Dapino, Marcelo J

    2017-01-01

    Ultrasonic additive manufacturing (UAM) is a solid-state technology for joining similar and dissimilar metal foils near room temperature by scrubbing them together with ultrasonic vibrations under pressure. Structural dynamics of the welding assembly and work piece influence how energy is transferred during the process and ultimately, part quality. To understand the effect of structural dynamics during UAM, a linear time-invariant model is proposed to relate the inputs of shear force and electric current to resultant welder velocity and voltage. Measured frequency response and operating performance of the welder under no load is used to identify model parameters. Using this model and in-situ measurements, shear force and welder efficiency are estimated to be near 2000N and 80% when welding Al 6061-H18 weld foil, respectively. Shear force and welder efficiency have never been estimated before in UAM. The influence of processing conditions, i.e., welder amplitude, normal force, and weld speed, on shear force and welder efficiency are investigated. Welder velocity was found to strongly influence the shear force magnitude and efficiency while normal force and weld speed showed little to no influence. The proposed model is used to describe high frequency harmonic content in the velocity response of the welder during welding operations and coupling of the UAM build with the welder.

  14. Sustainability Characterization for Additive Manufacturing.

    Science.gov (United States)

    Mani, Mahesh; Lyons, Kevin W; Gupta, S K

    2014-01-01

    Additive manufacturing (AM) has the potential to create geometrically complex parts that require a high degree of customization, using less material and producing less waste. Recent studies have shown that AM can be an economically viable option for use by the industry, yet there are some inherent challenges associated with AM for wider acceptance. The lack of standards in AM impedes its use for parts production since industries primarily depend on established standards in processes and material selection to ensure the consistency and quality. Inability to compare AM performance against traditional manufacturing methods can be a barrier for implementing AM processes. AM process sustainability has become a driver due to growing environmental concerns for manufacturing. This has reinforced the importance to understand and characterize AM processes for sustainability. Process characterization for sustainability will help close the gaps for comparing AM performance to traditional manufacturing methods. Based on a literature review, this paper first examines the potential environmental impacts of AM. A methodology for sustainability characterization of AM is then proposed to serve as a resource for the community to benchmark AM processes for sustainability. Next, research perspectives are discussed along with relevant standardization efforts.

  15. Children's understanding of additive concepts.

    Science.gov (United States)

    Robinson, Katherine M; Dubé, Adam K; Beatch, Jacqueline-Ann

    2017-04-01

    Most research on children's arithmetic concepts is based on one concept at a time, limiting the conclusions that can be made about how children's conceptual knowledge of arithmetic develops. This study examined six arithmetic concepts (identity, negation, commutativity, equivalence, inversion, and addition and subtraction associativity) in Grades 3, 4, and 5. Identity (a-0=a) and negation (a-a=0) were well understood, followed by moderate understanding of commutativity (a+b=b+a) and inversion (a+b-b=a), with weak understanding of equivalence (a+b+c=a+[b+c]) and associativity (a+b-c=[b-c]+a). Understanding increased across grade only for commutativity and equivalence. Four clusters were found: The Weak Concept cluster understood only identity and negation; the Two-Term Concept cluster also understood commutativity; the Inversion Concept cluster understood identity, negation, and inversion; and the Strong Concept cluster had the strongest understanding of all of the concepts. Grade 3 students tended to be in the Weak and Inversion Concept clusters, Grade 4 students were equally likely to be in any of the clusters, and Grade 5 students were most likely to be in the Two-Term and Strong Concept clusters. The findings of this study highlight that conclusions about the development of arithmetic concepts are highly dependent on which concepts are being assessed and underscore the need for multiple concepts to be investigated at the same time.

  16. Septic tank additive impacts on microbial populations.

    Science.gov (United States)

    Pradhan, S; Hoover, M T; Clark, G H; Gumpertz, M; Wollum, A G; Cobb, C; Strock, J

    2008-01-01

    Environmental health specialists, other onsite wastewater professionals, scientists, and homeowners have questioned the effectiveness of septic tank additives. This paper describes an independent, third-party, field scale, research study of the effects of three liquid bacterial septic tank additives and a control (no additive) on septic tank microbial populations. Microbial populations were measured quarterly in a field study for 12 months in 48 full-size, functioning septic tanks. Bacterial populations in the 48 septic tanks were statistically analyzed with a mixed linear model. Additive effects were assessed for three septic tank maintenance levels (low, intermediate, and high). Dunnett's t-test for tank bacteria (alpha = .05) indicated that none of the treatments were significantly different, overall, from the control at the statistical level tested. In addition, the additives had no significant effects on septic tank bacterial populations at any of the septic tank maintenance levels. Additional controlled, field-based research iswarranted, however, to address additional additives and experimental conditions.

  17. Additive Manufacturing of Aerospace Propulsion Components

    Science.gov (United States)

    Misra, Ajay K.; Grady, Joseph E.; Carter, Robert

    2015-01-01

    The presentation will provide an overview of ongoing activities on additive manufacturing of aerospace propulsion components, which included rocket propulsion and gas turbine engines. Future opportunities on additive manufacturing of hybrid electric propulsion components will be discussed.

  18. ADHD Diet: Do Food Additives Cause Hyperactivity?

    Science.gov (United States)

    ... There's no solid evidence that food additives cause attention-deficit/hyperactivity disorder (ADHD). However, the topic of food additives and their possible effects is controversial. Some studies indicate that certain food ...

  19. [Safety of food additives in Japan].

    Science.gov (United States)

    Ito, Sumio

    2011-01-01

    Recently, many accidents relating to food happened in Japan. The consumer's distrust for food, food companies, and the administration is increasing. The consumer especially has an extreme refusal feeling for chemicals such as food additives and agricultural chemicals, and begins to request agricultural chemical-free vegetables and food additive-free food. Food companies also state no agricultural chemicals and no food additives to correspond with consumers' request and aim at differentiating. The food additive is that the Ministry of Health, Labour and Welfare specifies the one that person's health might not be ruined by providing for Food Sanitation Law Article 10 in our country. The standard for food additives and standard for use of food additives are provided according to regulations of Food Sanitation Law Article 11. Therefore, it is thought that the food additive used is safe now. Then, it reports on the procedure and the safety examination, etc. in our country for designation for food additive this time.

  20. Additive-driven assembly of block copolymers

    Science.gov (United States)

    Lin, Ying; Daga, Vikram; Anderson, Eric; Watkins, James

    2011-03-01

    One challenge to the formation of well ordered hybrid materials is the incorporation of nanoscale additives including metal, semiconductor and dielectric nanoparticles at high loadings while maintaining strong segregation. Here we describe the molecular and functional design of small molecule and nanoparticle additives that enhance phase segregation in their block copolymer host and enable high additive loadings. Our approach includes the use of hydrogen bond interactions between the functional groups on the additive or particle that serve as hydrogen bond donors and one segment of the block copolymer containing hydrogen bond acceptors. Further, the additives show strong selectively towards the targeted domains, leading to enhancements in contrast between properties of the phases. In addition to structural changes, we explore how large changes in the thermal and mechanical properties occur upon incorporation of the additives. Generalization of this additive-induced ordering strategy to various block copolymers will be discussed.

  1. Building a Competitive Edge with Additive Manufacturing

    Science.gov (United States)

    2013-02-14

    construct ceramic molds for complex metal parts using a 3D printing technique. They estimate the new 6 technique could eliminate all of the...processes. They include 3D printing and Additive Beam Techniques.15 Most Additive Manufacturing techniques are specific to certain classes of materials...9 Example Additive Manufacturing Techniques16 3D Printing Additive Beam Stereolithography (SLA) Direct Metal Laser Sintering (DMLS

  2. Navy Additive Manufacturing: Adding Parts, Subtracting Steps

    Science.gov (United States)

    2015-06-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA MBA PROFESSIONAL REPORT NAVY ADDITIVE MANUFACTURING : ADDING PARTS, SUBTRACTING...blank) 2. REPORT DATE June 2015 3. REPORT TYPE AND DATES COVERED MBA Professional Report 4. TITLE AND SUBTITLE NAVY ADDITIVE MANUFACTURING ...DISTRIBUTION CODE 13. ABSTRACT (maximum 200 words) This study examines additive manufacturing (AM) and describes its potential impact on the Navy’s Supply

  3. The identities of additive binary arithmetics

    CERN Document Server

    Klyachko, Anton A

    2011-01-01

    Operations of arbitrary arity expressible via addition modulo 2^n and bitwise addition modulo 2 admit a simple description. The identities connecting these two additions have finite basis. Moreover, the universal algebra with these two operations is rationally equivalent to a nilpotent ring and, therefore, generates a Specht variety.

  4. 14 CFR 29.927 - Additional tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Additional tests. 29.927 Section 29.927... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 29.927 Additional tests. (a) Any additional dynamic, endurance, and operational tests, and vibratory investigations necessary to...

  5. 14 CFR 27.927 - Additional tests.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Additional tests. 27.927 Section 27.927... STANDARDS: NORMAL CATEGORY ROTORCRAFT Powerplant Rotor Drive System § 27.927 Additional tests. (a) Any additional dynamic, endurance, and operational tests, and vibratory investigations necessary to...

  6. Lubricant additive concentrate containing isomerized jojoba oil

    Energy Technology Data Exchange (ETDEWEB)

    Arndt, G.

    1987-05-12

    This patent describes a crankcase motor oil additive concentrate intended to be added to a conventional crankcase motor oil to improve its ability to lubricate and protect the engine. The additive concentrate comprises the following components: A petroleum base stock of lubricating quality and viscosity. The base stock comprises from about 13.5 to 90 weight percent of the additive concentrate; a detergent-inhibitor package. The package is present at from about 7 to about 40 weight percent of the concentrate; a supplemental antiwear additive selected from the salts of dialkyl dithiophosporic acids. The additive is present at a level of from about 1 to about 10 weight percent of the concentrate; and a supplemental antiwear additive selected from the class of sulfurized olefins. The additive is present at a level of from about 1 to about 10 weight percent of the concentrate.

  7. Cincinnati Big Area Additive Manufacturing (BAAM)

    Energy Technology Data Exchange (ETDEWEB)

    Duty, Chad E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Love, Lonnie J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-03-04

    Oak Ridge National Laboratory (ORNL) worked with Cincinnati Incorporated (CI) to demonstrate Big Area Additive Manufacturing which increases the speed of the additive manufacturing (AM) process by over 1000X, increases the size of parts by over 10X and shows a cost reduction of over 100X. ORNL worked with CI to transition the Big Area Additive Manufacturing (BAAM) technology from a proof-of-principle (TRL 2-3) demonstration to a prototype product stage (TRL 7-8).

  8. 21 CFR 25.32 - Foods, food additives, and color additives.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Foods, food additives, and color additives. 25.32... ENVIRONMENTAL IMPACT CONSIDERATIONS Categorical Exclusions § 25.32 Foods, food additives, and color additives.... (b) Action on a request for exemption for investigational use of a food additive if the food......

  9. Merits and Demerits of Food Additives

    Institute of Scientific and Technical Information of China (English)

    Xuening; YANG; Yong; ZHAN

    2014-01-01

    Food additive is a double-edged sword. It has merits and demerits. Food additives have such merits as improving sensory properties of foods,preventing deterioration and extending the shelf life,increasing varieties of foods,enhancing convenience of foods,facilitating food processing,and satisfying other demands. However,excessive and illegal use of food additives will exert adverse influence on food security.Therefore,it is required to take proper measures to bring merits of food additives into full play,and get rid of their demerits.

  10. Allergic and immunologic reactions to food additives.

    Science.gov (United States)

    Gultekin, Fatih; Doguc, Duygu Kumbul

    2013-08-01

    For centuries, food additives have been used for flavouring, colouring and extension of the useful shelf life of food, as well as the promotion of food safety. During the last 20 years, the studies implicating the additives contained in foods and medicine as a causative factor of allergic reactions have been proliferated considerably. In this review, we aimed to overview all of the food additives which were approved to consume in EU and find out how common and serious allergic reactions come into existence following the consuming of food additives.

  11. DNA addition using linear self-assembly

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jian; QIAN LuLu; LIU Qiang; ZHANG ZhiZhou; HE Lin

    2007-01-01

    This paper presents a DNA algorithm which adds two nonnegative binary integers using self-assembly in constant steps. The approach has the benefit of greater experimental simplicity when compared with previous DNA addition algorithms. For the addition of two binary n-bit integers, O(n) is different from DNA strands and only O(1) biochemical experimental procedures are required.

  12. 75 FR 8927 - Procurement List; Proposed Addition

    Science.gov (United States)

    2010-02-26

    ... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Proposed Addition AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Proposed addition to the Procurement List. SUMMARY: The Committee is proposing to add to the Procurement List products to be provided by a...

  13. 78 FR 7412 - Procurement List; Proposed Additions

    Science.gov (United States)

    2013-02-01

    ... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Proposed Additions AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Proposed Additions to the Procurement List. SUMMARY: The Committee is proposing to add products to the Procurement List that will be furnished by...

  14. 78 FR 7413 - Procurement List; Additions

    Science.gov (United States)

    2013-02-01

    ... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Additions AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Additions to the Procurement List. SUMMARY: This action adds products and services to the Procurement List that will be furnished by nonprofit...

  15. 78 FR 5423 - Procurement List; Additions

    Science.gov (United States)

    2013-01-25

    ... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Additions AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Additions to the Procurement List. SUMMARY: This action adds products to the Procurement List that will be furnished by the nonprofit agency...

  16. 78 FR 9386 - Procurement List; Addition

    Science.gov (United States)

    2013-02-08

    ... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Addition AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Addition to the Procurement List. SUMMARY: This action adds a service to the Procurement List that will be provided by a nonprofit agency employing...

  17. 75 FR 8926 - Procurement List; Additions

    Science.gov (United States)

    2010-02-26

    ... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Additions AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Additions to the Procurement List. SUMMARY: This action adds to the Procurement List products and a service to be furnished by nonprofit...

  18. 78 FR 5423 - Procurement List; Proposed Additions

    Science.gov (United States)

    2013-01-25

    ... FROM PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Proposed Additions AGENCY: Committee... Procurement List. SUMMARY: The Committee is proposing to add products to the Procurement List that will be... have other severe disabilities. The following products are proposed for addition to the...

  19. 76 FR 7824 - Procurement List; Proposed Additions

    Science.gov (United States)

    2011-02-11

    ... PEOPLE WHO AREBLIND OR SEVERELY DISABLED Procurement List; Proposed Additions AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Proposed additions to the Procurement List. SUMMARY: The Committee is proposing to add products to the Procurement List that will be furnished by...

  20. Contexts for Column Addition and Subtraction

    Science.gov (United States)

    Lopez Fernandez, Jorge M.; Velazquez Estrella, Aileen

    2011-01-01

    In this article, the authors discuss their approach to column addition and subtraction algorithms. Adapting an original idea of Paul Cobb and Erna Yackel's from "A Contextual Investigation of Three-Digit Addition and Subtraction" related to packing and unpacking candy in a candy factory, the authors provided an analogous context by…

  1. 75 FR 60739 - Procurement List; Proposed Additions

    Science.gov (United States)

    2010-10-01

    .... NPA: CW Resources, Inc., New Britain, CT. Contracting Activity: Dept. of the Army, XRA W7NN USPFO... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Proposed Additions AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Proposed additions to the procurement...

  2. 48 CFR 1603.7002 - Additional guidelines.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Additional guidelines. 1603.7002 Section 1603.7002 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL... OF INTEREST Misleading, Deceptive, or Unfair Advertising 1603.7002 Additional guidelines....

  3. French and English Together: An "Additive" Experience

    Science.gov (United States)

    Wiltshire, Jessica; Harbon, Lesley

    2010-01-01

    This paper examines the nature of the "additive" experience of a bilingual French-English curriculum at Killarney Heights Public School in New South Wales. Predictably, the well-supported "additive" nature of the languages program model elicited positive reactions regarding educational success. The paper also explores issues…

  4. 78 FR 4133 - Procurement List; Addition

    Science.gov (United States)

    2013-01-18

    ... FROM PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Addition AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Addition to the Procurement List. SUMMARY: This action adds a service to the Procurement List that will be provided by a nonprofit...

  5. 78 FR 2378 - Procurement List, Addition

    Science.gov (United States)

    2013-01-11

    ... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List, Addition AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Addition to the Procurement List. SUMMARY: This action adds a product to the Procurement List that will be furnished by a nonprofit agency employing...

  6. 75 FR 4784 - Procurement List; Addition

    Science.gov (United States)

    2010-01-29

    ... PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Addition AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Addition to the Procurement List. SUMMARY: This action adds to the Procurement List a service to be furnished by a nonprofit agency employing persons who...

  7. 75 FR 6869 - Procurement List; Additions

    Science.gov (United States)

    2010-02-12

    ...; ] COMMITTEE FOR PURCHASE FROM PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Additions AGENCY: Committee for Purchase From People Who Are Blind or Severely Disabled. ACTION: Additions to the Procurement List. SUMMARY: This action adds to the Procurement List products and a service to be furnished...

  8. 12 CFR 619.9010 - Additional security.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Additional security. 619.9010 Section 619.9010 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM DEFINITIONS § 619.9010 Additional security. Supplementary collateral to the primary security taken in connection with the loan....

  9. Additions to the Avifauna of suriname

    NARCIS (Netherlands)

    Mees, G.F.

    1974-01-01

    It is self-evident that as the avifauna of a country becomes better known, the number of additions to its avifauna one can expect to make in a given period, must decrease. On the other hand, it may be said that for the same reason the value of each addition increases. During a stay in Suriname of ab

  10. Developing Multiplicative Thinking from Additive Reasoning

    Science.gov (United States)

    Tobias, Jennifer M.; Andreasen, Janet B.

    2013-01-01

    As students progress through elementary school, they encounter mathematics concepts that shift from additive to multiplicative situations (NCTM 2000). When they encounter fraction problems that require multiplicative thinking, they tend to incorrectly extend additive properties from whole numbers (Post et al. 1985). As a result, topics such as …

  11. Effect of glutathione addition in sparkling wine.

    Science.gov (United States)

    Webber, Vanessa; Dutra, Sandra Valduga; Spinelli, Fernanda Rodrigues; Marcon, Ângela Rossi; Carnieli, Gilberto João; Vanderlinde, Regina

    2014-09-15

    This study aims to evaluate the effect of the addition of glutathione (GSH) on secondary aromas and on the phenolic compounds of sparkling wine elaborated by traditional method. It was added 10 and 20 mg L(-1) of GSH to must and to base wine. The determination of aroma compounds was performed by gas chromatography. Phenolic compounds and glutathione content were analyzed by high performance liquid chromatography. Sparkling wines with addition of GSH to must showed lower levels of total phenolic compounds and hydroxycinnamic acids. Furthermore, the sparkling wine with addition of GSH to must showed higher levels of 2-phenylethanol, 3-methyl-1-butanol and diethyl succinate, and lower concentrations of ethyl decanoate, octanoic and decanoic acids. The GSH addition to the must show a greater influence on sparkling wine than to base wine, however GSH addition to base wine seems retain higher SO2 free levels. The concentration of GSH added showed no significant difference.

  12. Anaerobic sludge digestion with a biocatalytic additive

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, S.; Henry, M.P.; Fedde, P.A.

    1982-01-01

    The objective of this research was to evaluate the effects of a lactobacillus additive an anaerobic sludge digestion under normal, variable, and overload operating conditions. The additive was a whey fermentation product of an acid-tolerant strain of Lactobacillus acidophilus fortified with CaCO/sub 3/, (NH/sub 4/)/sub 2/HPO/sub 4/, ferrous lactate, and lactic acid. The lactobacillus additive is multifunctional in nature and provides growth factors, metabolic intermediates, and enzymes needed for substrate degradation and cellular synthesis. The experimental work consisted of several pairs of parallel mesophilic (35/sup 0/C) digestion runs (control and test) conducted in five experimental phases. Baseline runs without the additive showed that the two experimental digesters had the same methane content, gas production rate (GPR), and ethane yield. The effect of the additive was to increase methane yield and GPR by about 5% (which was statistically significant) during digester operation at a loading rate (LR) of 3.2 kg VS/m/sup 3/-day and a hydraulic retention time (HRT) of 14 days. Data collected from the various experimental phases showed that the biochemical additive increased methane yield, gas production rate, and VS reduction, and decreased volatile acids accumulation. In addition, it enhanced digester buffer capacity and improved the fertilizer value and dewatering characteristics of the digested residue.

  13. Graphite and Hybrid Nanomaterials as Lubricant Additives

    Directory of Open Access Journals (Sweden)

    Zhenyu J. Zhang

    2014-04-01

    Full Text Available Lubricant additives, based on inorganic nanoparticles coated with organic outer layer, can reduce wear and increase load-carrying capacity of base oil remarkably, indicating the great potential of hybrid nanoparticles as anti-wear and extreme-pressure additives with excellent levels of performance. The organic part in the hybrid materials improves their flexibility and stability, while the inorganic part is responsible for hardness. The relationship between the design parameters of the organic coatings, such as molecular architecture and the lubrication performance, however, remains to be fully elucidated. A survey of current understanding of hybrid nanoparticles as lubricant additives is presented in this review.

  14. Fine-grained concrete with organomineral additive

    Directory of Open Access Journals (Sweden)

    Solovyov Vitaly

    2016-01-01

    Full Text Available The article deals with the issues concerning the formation of the structure and properties of fine-grained concrete with organomineral additive produced through mechanochemical activation of thermal power plant fly ash together with superplasticizer. The additive is produced in a high-speed activator at the collision particles’ speed of about 80 m/s. The use of the additive in fine-grained concrete in the amounts of 0.5-1% increased the strength by 30-50% and reduced the size and volume of pores. The cement consumption in such concrete is close to the cement consumption in common concrete of equal resistance.

  15. Additive Manufacturing of Ion Thruster Optics Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Plasma Controls will manufacture and test a set of ion optics for electric propulsion ion thrusters using additive manufacturing technology, also known as 3D...

  16. Non-additive measure and integral

    CERN Document Server

    Denneberg, Dieter

    1994-01-01

    Non-Additive Measure and Integral is the first systematic approach to the subject. Much of the additive theory (convergence theorems, Lebesgue spaces, representation theorems) is generalized, at least for submodular measures which are characterized by having a subadditive integral. The theory is of interest for applications to economic decision theory (decisions under risk and uncertainty), to statistics (including belief functions, fuzzy measures) to cooperative game theory, artificial intelligence, insurance, etc. Non-Additive Measure and Integral collects the results of scattered and often isolated approaches to non-additive measures and their integrals which originate in pure mathematics, potential theory, statistics, game theory, economic decision theory and other fields of application. It unifies, simplifies and generalizes known results and supplements the theory with new results, thus providing a sound basis for applications and further research in this growing field of increasing interest. It also co...

  17. Additions to the fern flora of Sulawesi

    NARCIS (Netherlands)

    Hovenkamp, P.H.; Joncheere, de G.J.

    1988-01-01

    A number of additions to the fern flora of Celebes are given here, including also the description of 15 new taxa in the Polypodiaceae, Cyatheaceae, Dennstaedtiaceae, Thelypteridaceae, Aspleniaceae, and Davalliaceae.

  18. 77 FR 32592 - Procurement List; Additions

    Science.gov (United States)

    2012-06-01

    ... notices of proposed additions to the Procurement List. After consideration of the material presented to it... CONS LGC, Beale AFB, CA. Service Type/Location: Contractor-Operated Civil Engineer Supply Store...

  19. 77 FR 51521 - Procurement List; Additions

    Science.gov (United States)

    2012-08-24

    ... certification were: 1. The action will not result in any additional reporting, recordkeeping or other compliance...: Operation Support Service, Aberdeen Proving Ground, MD, National Ground Intelligence Center (NGIC), Rivanna... Patricia Briscoe, Deputy Director, Business Operations, (Pricing and Information Management). BILLING...

  20. 77 FR 44218 - Procurement List; Additions

    Science.gov (United States)

    2012-07-27

    ... . SUPPLEMENTARY INFORMATION: Additions On 5/11/2012 (77 FR 27737-27738) and 6/1/2012 (77 FR 32591-32592), the...: 3895-00-NIB-0002--Asphalt Lute, Aluminum Head, Industrial Grade, 67'' Fiberglass Handle,...

  1. Evaluation of certain food additives and contaminants.

    Science.gov (United States)

    2013-01-01

    This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives and a food contaminant with a view to concluding as to safety concerns and to preparing specifications for identity and purity. The first part of the report contains a general discussion of the principles governing the toxicological evaluation of and assessment of dietary exposure to food additives. A summary follows of the Committee's evaluations of technical, toxicological and dietary exposure data for seven food additives (advantame; glucoamylase from Trichoderma reesei expressed in Trichoderma reesei; glycerol ester of gum rosin; glycerol ester of tall oil rosin; glycerol ester of wood rosin; nisin; and octenyl succinic acid modified gum arabic) and an assessment of dietary exposure to cadmium from cocoa and cocoa products. Specifications for the following food additives were revised: annatto extracts (solvent-extracted bixin and solvent-extracted norbixin); Benzoe tonkinensis; food additives containing aluminium and/or silicon; mineral oil (medium viscosity); modified starches; paprika extract; phosphates (analytical methods for the determination of phosphorus and revision of specifications); 3-phytase from Aspergillus niger expressed in Aspergillus niger; potassium aluminium silicate; and potassium aluminium silicate-based pearlescent pigments. Annexed to the report are tables summarizing the Committee's recommendations for dietary exposures to and toxicological evaluations of the food additives and contaminant considered.

  2. Additive manufacturing in production: challenges and opportunities

    Science.gov (United States)

    Ahuja, Bhrigu; Karg, Michael; Schmidt, Michael

    2015-03-01

    Additive manufacturing, characterized by its inherent layer by layer fabrication methodology has been coined by many as the latest revolution in the manufacturing industry. Due to its diversification of Materials, processes, system technology and applications, Additive Manufacturing has been synonymized with terminology such as Rapid prototyping, 3D printing, free-form fabrication, Additive Layer Manufacturing, etc. A huge media and public interest in the technology has led to an innovative attempt of exploring the technology for applications beyond the scope of the traditional engineering industry. Nevertheless, it is believed that a critical factor for the long-term success of Additive Manufacturing would be its ability to fulfill the requirements defined by the traditional manufacturing industry. A parallel development in market trends and product requirements has also lead to a wider scope of opportunities for Additive Manufacturing. The presented paper discusses some of the key challenges which are critical to ensure that Additive Manufacturing is truly accepted as a mainstream production technology in the industry. These challenges would highlight on various aspects of production such as product requirements, process management, data management, intellectual property, work flow management, quality assurance, resource planning, etc. In Addition, changing market trends such as product life cycle, mass customization, sustainability, environmental impact and localized production will form the foundation for the follow up discussion on the current limitations and the corresponding research opportunities. A discussion on ongoing research to address these challenges would include topics like process monitoring, design complexity, process standardization, multi-material and hybrid fabrication, new material development, etc.

  3. Additional renal arteries: incidence and morphometry.

    Science.gov (United States)

    Satyapal, K S; Haffejee, A A; Singh, B; Ramsaroop, L; Robbs, J V; Kalideen, J M

    2001-01-01

    Advances in surgical and uro-radiological techniques dictate a reappraisal and definition of renal arterial variations. This retrospective study aimed at establishing the incidence of additional renal arteries. Two subsets were analysed viz.: a) Clinical series--130 renal angiograms performed on renal transplant donors, 32 cadaver kidneys used in renal transplantation b) Cadaveric series--74 en-bloc morphologically normal kidney pairs. The sex and race distribution was: males 140, females 96; African 84, Indian 91, White 43 and "Coloured" 18, respectively. Incidence of first and second additional arteries were respectively, 23.2% (R: 18.6%; L: 27.6%) and 4.5% (R: 4.7%; L: 4.4%). Additional arteries occurred more frequently on the left (L: 32.0%; R: 23.3%). The incidence bilaterally was 10.2% (first additional arteries, only). The sex and race incidence (first and second additional) was: males, 28.0%, 5.1%; females, 16.4%, 3.8% and African 31.1%, 5.4%; Indian 13.5%, 4.5%; White 30.9%, 4.4% and "Coloured" 18.5%, 0%; respectively. Significant differences in the incidence of first additional arteries were noted between sex and race. The morphometry of additional renal arteries were lengths (cm) of first and second additional renal arteries: 4.5 and 3.8 (right), 4.9 and 3.7 (left); diameters: 0.4 and 0.3 (right), 0.3 and 0.3 (left). Detailed morphometry of sex and race were also recorded. No statistically significant differences were noted. Our results of the incidence of additional renal arteries of 27.7% compared favourably to that reported in the literature (weighted mean 28.1%). The study is unique in recording detailed morphometry of these vessels. Careful techniques in the identification of this anatomical variation is important since it impacts on renal transplantation surgery, vascular operations for renal artery stenosis, reno-vascular hypertension, Takayasu's disease, renal trauma and uro-radiological procedures.

  4. [Intolerance to food additives: an update].

    Science.gov (United States)

    Cardinale, F; Mangini, F; Berardi, M; Sterpeta Loffredo, M; Chinellato, I; Dellino, A; Cristofori, F; Di Domenico, F; Mastrototaro, M F; Cappiello, A; Centoducati, T; Carella, F; Armenio, L

    2008-12-01

    Contrary to common believing, the prevalence of the intolerance to food additives in the general population is rather low. Nowadays many doubts persist with regard both to the pathogenetic mechanisms and to the clinical and diagnostic aspects in this field. Symptoms due to, or exacerbated from, food additives usually involve non-IgE-mediate mechanisms (pseudo-allergic reactions, PAR) and are usually less severe of those induced by food allergy. The most frequent clinical feature of the intolerance to food additives still remains the urticaria-angioedema syndrome, although these substances are really involved only in a minority of patients. Other possible clinical features include anaphylaxis, atopic eczema, behaviour disturbances, asthma and non-allergic rhinitis. The diagnostic approach consists in diary cards, reporting symptoms and food habits, elimination diet and double blinded placebo-controlled oral challenge with suspected additives. However, such procedure still remains poorly standardized and numerous uncertainties persist with regard to optimal conditions for performing and interpret the challenge results. The therapeutic approach consists in the exclusion of foods and products containing the additive involved, and, in patients not compliant to the diet, in treatment with symptomatic drugs.

  5. Testing for additivity with B-splines

    Institute of Scientific and Technical Information of China (English)

    Heng-jian CUI; Xu-ming HE; Li LIU

    2007-01-01

    Regression splines are often used for fitting nonparametric functions, and they work especially well for additivity models. In this paper, we consider two simple tests of additivity: an adaptation of Tukey's one degree of freedom test and a nonparametric version of Rao's score test. While the Tukey-type test can detect most forms of the local non-additivity at the parametric rate of O(n-1/2), the score test is consistent for all alternative at a nonparametric rate. The asymptotic distribution of these test statistics is derived under both the null and local alternative hypotheses. A simulation study is conducted to compare their finite-sample performances with some existing kernelbased tests. The score test is found to have a good overall performance.

  6. Mass Additivity and A Priori Entailment

    CERN Document Server

    McQueen, Kelvin J

    2015-01-01

    The principle of mass additivity states that the mass of a composite object is the sum of the masses of its elementary components. Mass additivity is true in Newtonian mechanics but false in special relativity. Physicists have explained why mass additivity is true in Newtonian mechanics by reducing it to Newton's microphysical laws. This reductive explanation does not fit well with deducibility theories of reductive explanation such as the modern Nagelian theory of reduction, and the a priori entailment theory of reduction that is prominent in the philosophy of mind. Nonetheless, I argue that a reconstruction of the explanation that incorporates distinctively philosophical concepts in fact fits both theories. I discuss the implications of this result for both theories and for the reductive explanation of consciousness.

  7. Non-additive measures theory and applications

    CERN Document Server

    Narukawa, Yasuo; Sugeno, Michio; 9th International Conference on Modeling Decisions for Artificial Intelligence (MDAI 2012)

    2014-01-01

    This book provides a comprehensive and timely report in the area of non-additive measures and integrals. It is based on a panel session on fuzzy measures, fuzzy integrals and aggregation operators held during the 9th International Conference on Modeling Decisions for Artificial Intelligence (MDAI 2012) in Girona, Spain, November 21-23, 2012. The book complements the MDAI 2012 proceedings book, published in Lecture Notes in Computer Science (LNCS) in 2012. The individual chapters, written by key researchers in the field, cover fundamental concepts and important definitions (e.g. the Sugeno integral, definition of entropy for non-additive measures) as well some important applications (e.g. to economics and game theory) of non-additive measures and integrals. The book addresses students, researchers and practitioners working at the forefront of their field.  

  8. Testing for additivity with B-splines

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Regression splines are often used for fitting nonparametric functions, and they work especially well for additivity models. In this paper, we consider two simple tests of additivity: an adaptation of Tukey’s one degree of freedom test and a nonparametric version of Rao’s score test. While the Tukey-type test can detect most forms of the local non-additivity at the parametric rate of O(n-1/2), the score test is consistent for all alternative at a nonparametric rate. The asymptotic distribution of these test statistics is derived under both the null and local alternative hypotheses. A simulation study is conducted to compare their finite-sample performances with some existing kernel-based tests. The score test is found to have a good overall performance.

  9. Evaluation of advanced polymers for additive manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Rios, Orlando [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Morrison, Crystal [PPG Industries, Pittsburgh, PA (United States)

    2015-09-01

    The goal of this Manufacturing Demonstration Facility (MDF) technical collaboration project between Oak Ridge National Laboratory (ORNL) and PPG Industries, Inc. was to evaluate the feasibility of using conventional coatings chemistry and technology to build up material layer-by-layer. The PPG-ORNL study successfully demonstrated that polymeric coatings formulations may overcome many limitations of common thermoplastics used in additive manufacturing (AM), allow lightweight nozzle design for material deposition and increase build rate. The materials effort focused on layer-by-layer deposition of coatings with each layer fusing together. The combination of materials and deposition results in an additively manufactured build that has sufficient mechanical properties to bear the load of additional layers, yet is capable of bonding across the z-layers to improve build direction strength. The formulation properties were tuned to enable a novel, high-throughput deposition method that is highly scalable, compatible with high loading of reinforcing fillers, and is inherently low-cost.

  10. Combustion enhancing additives for coal firing

    Energy Technology Data Exchange (ETDEWEB)

    Katherine Le Manquais; Colin Snape; Ian McRobbie; Jim Barker [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering (SChEME)

    2007-07-01

    For pulverised fuel (pf) combustion, the level of unburnt carbon in fly ash is now considerably more problematic worldwide than a decade ago, because of the introduction of low NOx burners and the increased level of high inertinite in internationally traded coals. Thus, there is a major opportunity to develop an effective additive to improve carbon burnout and obviate the need for post-treatment of fly ash, which endeavours to meet specifications for filler/building materials applications and thereby avoid landfill. A robust comparison of the reactivity of different coals and their corresponding chars is necessary, in order to estimate the effects of such an additive on pf combustion. Coal chars have been generated on a laboratory scale using thermal gravimetric analysis (TGA) and on a larger scale using a drop tube furnace (DTF), which is more representative of the rapid heating rates and mixing achieved on pf combustion. The TGA results indicate that chars have varying levels of reactivity, dependent on the parent coal properties. When physically mixed with a propriety metal additive, the degree of enhancement to the reactivity of these chars also appeared reliant on the parent coal characteristics. Additionally it was demonstrated that DTF chars, whilst showing similar reactivity trends, are less reactive than the equivalent coal chars produced by the TGA. However, when mixed with the metal additive the DTF chars show a significantly greater improvement in reactivity than their analogous TGA chars, indicating the additive may have the greatest impact on the most unreactive carbon in the coal. 42 refs., 6 figs., 1 tab.

  11. Theory of atomic additivity in molecular hyperpolizabilities

    Science.gov (United States)

    Baird, James K.

    1987-01-01

    Hyperpolarizability is a function of frequency. This is called dispersion. Because of the Kramers-Kronig relations, researchers expect that a material that is dispersing light is also absorbing it. Where there is both dispersion and absorption, the molecular polarizabilities are complex functions of the frequency. This led researchers to consider atomic additivity in both the real and imaginary parts of the ordinary and hyperpolarizabilities. This effort is desirable not only from a theoretical point of view, but also because of the existence of a large body of complex refractive index data, which may be used to test the additivity principle with the complex valued ordinary dipole polarizability.

  12. Effusion plate using additive manufacturing methods

    Science.gov (United States)

    Johnson, Thomas Edward; Keener, Christopher Paul; Ostebee, Heath Michael; Wegerif, Daniel Gerritt

    2016-04-12

    Additive manufacturing techniques may be utilized to construct effusion plates. Such additive manufacturing techniques may include defining a configuration for an effusion plate having one or more internal cooling channels. The manufacturing techniques may further include depositing a powder into a chamber, applying an energy source to the deposited powder, and consolidating the powder into a cross-sectional shape corresponding to the defined configuration. Such methods may be implemented to construct an effusion plate having one or more channels with a curved cross-sectional geometry.

  13. Local Time of Additive Levy Process

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    We studied the problem of existence of jointly continuous local time for an additive process.Here, “local time” is understood in the sence of occupation density, and by an additive Lévy process we mean a process X={X(t), t∈Rd+)} which has the decomposition X= X1 X2 … XN. We prove that if the product of it slower index and N is greater than d, then a jointly continuous local time can be obtained via Berman's method.

  14. Breaking Barriers in Polymer Additive Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Love, Lonnie J [ORNL; Duty, Chad E [ORNL; Post, Brian K [ORNL; Lind, Randall F [ORNL; Lloyd, Peter D [ORNL; Kunc, Vlastimil [ORNL; Peter, William H [ORNL; Blue, Craig A [ORNL

    2015-01-01

    Additive Manufacturing (AM) enables the creation of complex structures directly from a computer-aided design (CAD). There are limitations that prevent the technology from realizing its full potential. AM has been criticized for being slow and expensive with limited build size. Oak Ridge National Laboratory (ORNL) has developed a large scale AM system that improves upon each of these areas by more than an order of magnitude. The Big Area Additive Manufacturing (BAAM) system directly converts low cost pellets into a large, three-dimensional part at a rate exceeding 25 kg/h. By breaking these traditional barriers, it is possible for polymer AM to penetrate new manufacturing markets.

  15. Study of the electrochemical oxidation of Am with lacunary heteropolyanions and silver nitrate; Etude de l'oxydation electrochimique de l'americium en presence d'heteropolyanions lacunaires et de nitrate d'argent en milieu aqueux acide

    Energy Technology Data Exchange (ETDEWEB)

    Chartier, D

    1999-07-01

    Electrochemical oxidation of Am(III) with certain lacunary heteropolyanions (LHPA {alpha}{sub 2}-P{sub 2}W{sub 17}O{sub 61}{sup 10-} or {alpha}SiW{sub 11}O{sub 39}{sup 8-}) and silver nitrate is an efficient way to prepare Am(VI). This document presents bibliographic data and an experimental study of the process. Thus, it has been established that Am(IV) is an intermediate species in the reaction and occurs in 1:1 (Amt{sup IV}LHPA) or 1:2 (Am {sup IV}(LHAP){sub 2}) complexes with the relevant LHPA. These 1:1 complexes of Am(IV) have been identified and isolated in this work whereas 1:2 complexes were known from previous studies. The reactivity of these complexes in oxidation shows that 1:1 complexes of Am(IV) are oxidised much more quickly than 1:2 complexes. Apparent stability constants of Am(III) and Am(IV) complexes with the relevant LHPA have been measured for a 1 M nitric acid medium. Thermodynamic data of the reaction are then assessed: redox potentials of Am pairs are computed for a 1 M nitric acid medium containing various amount of LHPA ligands. Those results show that the role of LHPA is to stabilize the intermediate species Am(IV) by lowering the Am(IV)/Am(III) pair potential of about 1 Volt. Nevertheless, if this stabilisation is too strong (i.e. of tungsto-silicate), the oxidation of Am(IV) requires high anodic potential (more than 2 V/ENH). Then, the faradic yield of the oxidation of americium is poor because of water oxidation. This study has also shown that the main role of silver is to catalyze the electrochemical oxidation of Am{sup IV}(LHPA){sub X} complexes. Indeed, these oxidations without silver are extremely slow. An oxygen tracer experiment has been performed during the oxidation of Am(III) in Am(VI). It has been shown that the oxygen atoms of Am(VI) (AMO{sub 2}{sup 2+}) come from water molecules of the solvent and not from the complexing oxygen atoms of the ligands. (author)

  16. 77 FR 71400 - Procurement List, Additions

    Science.gov (United States)

    2012-11-30

    ..., Vinyl, Adjustable 31'' to 55'', Fluorescent Green NSN: 4240-00-NIB-0052--Reflective Safety Belt, Vinyl, Adjustable 31'' to 55'', Dark Green NPA: Envision, Inc., Wichita, KS. Contracting Activity: DEFENSE LOGISTICS... . SUPPLEMENTARY INFORMATION: Additions On 8/24/2012 (77 FR 51522-51523) and 10/5/2012 (77 FR 60969), the...

  17. ADDITIVE FUNCTIONALS AND PERTURBATION OF SEMIGROUP

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The perturbation of semigroup by a multiplicative functional with bounded variation is investigated in the frame of weak duality. The strong continuity and Schrodinger type equation of the perturbated semigroup are discussed. A few switching identities and formulae conerning dual additive functionals and Revuz measures are given.

  18. ADDITIVE FUNCTIONALS AND PERTURBATION OF SEMIGROUP

    Institute of Scientific and Technical Information of China (English)

    JINMENGWEI; YINGJIANGANG

    2001-01-01

    The perturbation of semigroup by a multiplicative functional with bounded variation is investigated in the frame of weak duality. The strong continuity and SchrSdinger type equation of the perturbated semigroup are discussed. A few switching identities and formulae conerning dual additive functionais and Revuz measures are given.

  19. Release of additives from packaging plastics

    NARCIS (Netherlands)

    Helmroth, I.E.

    2002-01-01

    Keywords : migration, diffusion, additives, polymer, low density polyethylene, polymer swelling, Fick, stochastic modellingThe diffusion of small molecules from polymers into food is studied. A better understanding of this process is important for the development of mathematical models to predict mi

  20. Predicting Color Output of Additive Manufactured Parts

    DEFF Research Database (Denmark)

    Eiríksson, Eyþór Rúnar; Pedersen, David Bue; Aanæs, Henrik

    2015-01-01

    In this paper we address the colorimetric performance of a multicolor additive manufacturing process. A method on how to measure and characterize color performance of said process is presented. Furthermore, a method on predicting the color output is demonstrated, allowing for previsualization...

  1. Fully additive chip packaging: science or fiction?

    NARCIS (Netherlands)

    Oosterhuis, G.; Zon, C.M.B. van der; Maalderink, H.H.

    2011-01-01

    The current trend in IC packaging towards an ever increasing degree of integration, combined with a high level of production flexibility calls for novel approaches in manufacturing. To address these challenges in a flexible manufacturing setting, TNO investigated to what extend mask-less additive ma

  2. Additive Manufacturing: From Rapid Prototyping to Flight

    Science.gov (United States)

    Prater, Tracie

    2015-01-01

    Additive manufacturing (AM) offers tremendous promise for the rocket propulsion community. Foundational work must be performed to ensure the safe performance of AM parts. Government, industry, and academia must collaborate in the characterization, design, modeling, and process control to accelerate the certification of AM parts for human-rated flight.

  3. Additive strengthening mechanisms in dispersion hardened polycrystals

    DEFF Research Database (Denmark)

    Hansen, Niels; Ralph, B.

    1986-01-01

    the addition of strength components from various elements of the microstructure and substructure might explain this behaviour are investigated. It is shown that a linear combination of a matrix friction stress, an Orowan bowing stress, a matrix mean stress from the particles and a combined dislocation...

  4. [Information about phosphorus additives and nutritional counseling].

    Science.gov (United States)

    Kido, Shinsuke; Nomura, Kengo; Sasaki, Shohei; Shiozaki, Yuji; Segawa, Hiroko; Tatsumi, Sawako

    2012-10-01

    Hyperphosphatemia is a common disorder in patients with chronic kidney disease (CKD) , and may result in hyperparathyroidism and renal osteodystrophy. Hyperphosphatemia also may contribute to deterioration vascular calcification and increase mortality. Hence, correction and prevention of hyperphosphatemia is a main component of the management of CKD. This goal is usually approached both by administering phosphorus binders and by restricting dietary phosphorus (P) intake. Dietary intake of phosphorus (P) is derived largely from foods with high protein content or food additives and is an important determinant of P balance in patient with CKD. Food additives (PO4) can dramatically increase the amount of P consumed in the daily diet, especially because P is more readily absorbed in its inorganic form. In addition, information about the P content and type in prepared foods is often unavailable or misleading. Therefore, during dietary counseling of patients with CKD, we recommended that they consider both the absolute dietary P content and the P-to-protein ratio of foods and meals including food additives.

  5. Finding phosphorus containing additives in manufactured foods

    Directory of Open Access Journals (Sweden)

    Lyn Lloyd

    2012-06-01

    This reflects manufactured foods in NZ and it is likely that these results could be generalized to countries with similar food patterns and supplies. Quantitative data in manufactured foods is unlikely to be available to guide patient choice so qualitative information of where to find P additives can be helpful.

  6. 7 CFR 955.91 - Additional parties.

    Science.gov (United States)

    2010-01-01

    ... Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Marketing Agreement § 955.91 Additional parties. After the effective date thereof, any handler may become a... delivered to the Secretary, and the benefits, privileges, and immunities conferred by this agreement...

  7. Children's Understanding of Addition and Subtraction Concepts

    Science.gov (United States)

    Robinson, Katherine M.; Dube, Adam K.

    2009-01-01

    After the onset of formal schooling, little is known about the development of children's understanding of the arithmetic concepts of inversion and associativity. On problems of the form a+b-b (e.g., 3+26-26), if children understand the inversion concept (i.e., that addition and subtraction are inverse operations), then no calculations are needed…

  8. 76 FR 55883 - Procurement List; Proposed Addition

    Science.gov (United States)

    2011-09-09

    ... From the Federal Register Online via the Government Publishing Office COMMITTEE FOR PURCHASE FROM PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List; Proposed Addition AGENCY: Committee for... Center (SPOC), 5015 S. IH-35, Austin, TX. NPA: Austin Task, Inc., Austin, TX. Contracting Activity:...

  9. 76 FR 70422 - Procurement List Additions

    Science.gov (United States)

    2011-11-14

    ... From the Federal Register Online via the Government Publishing Office COMMITTEE FOR PURCHASE FROM PEOPLE WHO ARE BLIND OR SEVERELY DISABLED Procurement List Additions AGENCY: Committee for Purchase From... Center (SPOC), 5015 S. IH-35, Austin, TX NPA: Austin Task, Inc., Austin, TX. Contracting Activity:...

  10. Leaching of Plastic Additives to Marine Organisms

    NARCIS (Netherlands)

    Koelmans, A.A.; Besseling, E.; Foekema, E.M.

    2014-01-01

    It is often assumed that ingestion of microplastics by aquatic species leads to increased exposure to plastic additives. However, experimental data or model based evidence is lacking. Here we assess the potential of leaching of nonylphenol (NP) and bisphenol A (BPA) in the intestinal tracts of Areni

  11. Additive Manufacturing of Biomaterials, Tissues, and Organs

    NARCIS (Netherlands)

    Zadpoor, Amir A; Malda, Jos

    2017-01-01

    The introduction of additive manufacturing (AM), often referred to as three-dimensional (3D) printing, has initiated what some believe to be a manufacturing revolution, and has expedited the development of the field of biofabrication. Moreover, recent advances in AM have facilitated further developm

  12. Efficient classification for additive kernel SVMs.

    Science.gov (United States)

    Maji, Subhransu; Berg, Alexander C; Malik, Jitendra

    2013-01-01

    We show that a class of nonlinear kernel SVMs admits approximate classifiers with runtime and memory complexity that is independent of the number of support vectors. This class of kernels, which we refer to as additive kernels, includes widely used kernels for histogram-based image comparison like intersection and chi-squared kernels. Additive kernel SVMs can offer significant improvements in accuracy over linear SVMs on a wide variety of tasks while having the same runtime, making them practical for large-scale recognition or real-time detection tasks. We present experiments on a variety of datasets, including the INRIA person, Daimler-Chrysler pedestrians, UIUC Cars, Caltech-101, MNIST, and USPS digits, to demonstrate the effectiveness of our method for efficient evaluation of SVMs with additive kernels. Since its introduction, our method has become integral to various state-of-the-art systems for PASCAL VOC object detection/image classification, ImageNet Challenge, TRECVID, etc. The techniques we propose can also be applied to settings where evaluation of weighted additive kernels is required, which include kernelized versions of PCA, LDA, regression, k-means, as well as speeding up the inner loop of SVM classifier training algorithms.

  13. 77 FR 60969 - Procurement List; Additions

    Science.gov (United States)

    2012-10-05

    ...-0655, or email CMTEFedReg@AbilityOne.gov . SUPPLEMENTARY INFORMATION: Additions On 8/3/2012 (77 FR...: 7510-00-NIB-1855--Correction Tape, Pen Style, Retractable. NPA: Industries for the Blind, Inc., West.../Location: Janitorial Service, U.S. Department of Agriculture Natural Resources, Conservation...

  14. Clinica use of platelet additive solutions.

    Science.gov (United States)

    van Rhenen, Dick J

    2007-12-01

    Randomised clinical trial (RCT) to study the clinical efficacy and safety of new platelet products using platelet additive solutions are scarce. In this paper a number of recent RCT's is discussed. It can be the start of a development where new transfusion products enter a RCT before the product is applied in clinical practice.

  15. Boolean analysis of addition and multiplication

    Energy Technology Data Exchange (ETDEWEB)

    Faltin, F. (Cornell Univ., Ithaca, NY); Metropolis, N.; Ross, B.; Rota, G.-C.

    1977-01-01

    The notions of binary string and binary symmetric function are introduced, and basic results presented. Boolean algorithms are given for binary addition and multiplication. An analysis of the redundancies involved is straightforward. The examination of carry propagation which arises in the Boolean analysis of functions may lead to a new interpretation of the notion of computational complexity.

  16. Highly stereoselective addition of stannylcuprates to alkynones

    DEFF Research Database (Denmark)

    Nielsen, Thomas Eiland; de Dios, M.A.C.; Tanner, David Ackland

    2002-01-01

    The addition of stannylcuprate reagents such as (Bu3Sn)(PhS)CuLi to alkynones has been found to proceed in high yield and with excellent stereoselectivity for the Z isomer of the product (>95%). The behavior of the stannylcuprates is thus very different from that of their "carbocuprate" counterpa...

  17. 77 FR 42700 - Procurement List; Additions

    Science.gov (United States)

    2012-07-20

    ... Contracting Command--Aberdeen Proving Ground, Natick Contracting Division, Natick MA. Comments were received...--Aberdeen Proving Ground, Natick Contracting Division, Natick MA. Services Service Type/Location: Laundry... . SUPPLEMENTARY INFORMATION: Additions On 5/18/2012 (77 FR 29596) and 5/25/2012 (77 FR 31335-31336), the...

  18. 76 FR 18189 - Procurement List; Additions

    Science.gov (United States)

    2011-04-01

    ... Center, Aberdeen Proving Ground, MD. Patricia Briscoe, Deputy Director, Business Operations Pricing and... INFORMATION: Additions On 1/28/2011 (76 FR 5142-5143), the Committee for Purchase From People Who Are Blind or... Contracting Center--Aberdeen, MD, (Off-site: 507 Kent Street, Utica NY). NPA: Central Association for...

  19. 31 CFR 306.125 - Additional requirements.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Additional requirements. 306.125 Section 306.125 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) FISCAL SERVICE, DEPARTMENT OF THE TREASURY BUREAU OF THE PUBLIC DEBT GENERAL REGULATIONS GOVERNING...

  20. 47 CFR 68.318 - Additional limitations.

    Science.gov (United States)

    2010-10-01

    ... TERMINAL EQUIPMENT TO THE TELEPHONE NETWORK Conditions for Terminal Equipment Approval § 68.318 Additional... receipt of CO ground start at the network demarcation point. (c) Line seizure by automatic telephone... proceeding to dial another number. (6) Network addressing signals shall be transmitted no earlier than:...

  1. AN AZERBAIDZHAN SSR. INSTITUTE OF ADDITIVE CHEMISTRY ADDITIVES TO LUBRICATING OILS. PROBLEMS OF SYNTHESIS, INVESTIGATION AND USE OF OIL ADDITIVES; FUELS AND POLYMER MATERIALS (SELECTED ARTICLES),

    Science.gov (United States)

    An Azerbaidzhan SSR. Institute of additive chemistry additives to lubricating oils . Problems of synthesis, investigation and use of oil additives; fuels and polymer materials (Selected articles)--Translation.

  2. Inhomogenous quantum codes (Ⅰ):additive case

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    In this paper,the quantum error-correcting codes are generalized to the inhomogenous quantumstate space Cq1  Cq2 ··· Cqn,where qi(1 i n) are arbitrary positive integers.By attaching an abelian group Ai of order qi to the space Cqi(1 i n),we present the stabilizer construction of such inhomogenous quantum codes,called additive quantum codes,in term of the character theory of the abelian group A = A1⊕A2⊕···⊕An.As usual case,such construction opens a way to get inhomogenous quantum codes from the classical mixed linear codes.We also present Singleton bound for inhomogenous additive quantum codes and show several quantum codes to meet such bound by using classical mixed algebraic-geometric codes.

  3. Identifying confounders using additive noise models

    CERN Document Server

    Janzing, Dominik; Mooij, Joris; Schoelkopf, Bernhard

    2012-01-01

    We propose a method for inferring the existence of a latent common cause ('confounder') of two observed random variables. The method assumes that the two effects of the confounder are (possibly nonlinear) functions of the confounder plus independent, additive noise. We discuss under which conditions the model is identifiable (up to an arbitrary reparameterization of the confounder) from the joint distribution of the effects. We state and prove a theoretical result that provides evidence for the conjecture that the model is generically identifiable under suitable technical conditions. In addition, we propose a practical method to estimate the confounder from a finite i.i.d. sample of the effects and illustrate that the method works well on both simulated and real-world data.

  4. Additive manufacturing of polymer-derived ceramics.

    Science.gov (United States)

    Eckel, Zak C; Zhou, Chaoyin; Martin, John H; Jacobsen, Alan J; Carter, William B; Schaedler, Tobias A

    2016-01-01

    The extremely high melting point of many ceramics adds challenges to additive manufacturing as compared with metals and polymers. Because ceramics cannot be cast or machined easily, three-dimensional (3D) printing enables a big leap in geometrical flexibility. We report preceramic monomers that are cured with ultraviolet light in a stereolithography 3D printer or through a patterned mask, forming 3D polymer structures that can have complex shape and cellular architecture. These polymer structures can be pyrolyzed to a ceramic with uniform shrinkage and virtually no porosity. Silicon oxycarbide microlattice and honeycomb cellular materials fabricated with this approach exhibit higher strength than ceramic foams of similar density. Additive manufacturing of such materials is of interest for propulsion components, thermal protection systems, porous burners, microelectromechanical systems, and electronic device packaging.

  5. Evolution of solidification texture during additive manufacturing.

    Science.gov (United States)

    Wei, H L; Mazumder, J; DebRoy, T

    2015-11-10

    Striking differences in the solidification textures of a nickel based alloy owing to changes in laser scanning pattern during additive manufacturing are examined based on theory and experimental data. Understanding and controlling texture are important because it affects mechanical and chemical properties. Solidification texture depends on the local heat flow directions and competitive grain growth in one of the six preferred growth directions in face centered cubic alloys. Therefore, the heat flow directions are examined for various laser beam scanning patterns based on numerical modeling of heat transfer and fluid flow in three dimensions. Here we show that numerical modeling can not only provide a deeper understanding of the solidification growth patterns during the additive manufacturing, it also serves as a basis for customizing solidification textures which are important for properties and performance of components.

  6. Addition of malodorants to lighter gas

    DEFF Research Database (Denmark)

    Neela, Vasu; von Solms, Nicolas

    2014-01-01

    to lighter gas components. The aim is to find substances that not only have the correct physiological effect (discourage abuse) but also the correct physical behavior upon addition to lighter gas (solubility, phase behavior). Specifically the way the malodorant partitions between the vapor and liquid phase......Relevant thermodynamic and phase behavior of mixtures created by adding malodorants to lighter gas to discourage its abuse have been studied. The influence of physical factors such as temperature, pressure and concentration of the selected substances with lighter gas is studied. This work...... represents one component in a larger study examining the feasibility of adding malodorants to lighter gas and focuses on the physical chemistry or chemical engineering aspects of the problem. An initial set of 27 compounds was selected based on deterrent effect (odor) in order to find suitable additives...

  7. Weldability of Additive Manufactured Stainless Steel

    Science.gov (United States)

    Matilainen, Ville-Pekka; Pekkarinen, Joonas; Salminen, Antti

    Part size in additive manufacturing is limited by the size of building area of AM equipment. Occasionally, larger constructions that AM machines are able to produce, are needed, and this creates demand for welding AM parts together. However there is very little information on welding of additive manufactured stainless steels. The aim of this study was to investigate the weldability aspects of AM material. In this study, comparison of the bead on plate welds between AM parts and sheet metal parts is done. Used material was 316L stainless steel, AM and sheet metal, and parts were welded with laser welding. Weld quality was evaluated visually from macroscopic images. Results show that there are certain differences in the welds in AM parts compared to the welds in sheet metal parts. Differences were found in penetration depths and in type of welding defects. Nevertheless, this study presents that laser welding is suitable process for welding AM parts.

  8. Additive manufacturing of polymer-derived ceramics

    Science.gov (United States)

    Eckel, Zak C.; Zhou, Chaoyin; Martin, John H.; Jacobsen, Alan J.; Carter, William B.; Schaedler, Tobias A.

    2016-01-01

    The extremely high melting point of many ceramics adds challenges to additive manufacturing as compared with metals and polymers. Because ceramics cannot be cast or machined easily, three-dimensional (3D) printing enables a big leap in geometrical flexibility. We report preceramic monomers that are cured with ultraviolet light in a stereolithography 3D printer or through a patterned mask, forming 3D polymer structures that can have complex shape and cellular architecture. These polymer structures can be pyrolyzed to a ceramic with uniform shrinkage and virtually no porosity. Silicon oxycarbide microlattice and honeycomb cellular materials fabricated with this approach exhibit higher strength than ceramic foams of similar density. Additive manufacturing of such materials is of interest for propulsion components, thermal protection systems, porous burners, microelectromechanical systems, and electronic device packaging.

  9. The addition of disilanes to cumulenes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yiyuan [Iowa State Univ., Ames, IA (United States)

    1997-10-08

    The syntheses of silicon-containing compounds and the studies of their rearrangements have been active research areas in the Barton research group. Previously, the addition of disilanes to acetylenes was studied in the group and an intramolecular 2S + 2A mechanism has been proposed. In this thesis, the work is focused on the addition of disilanes to cumulenes. The syntheses of the precursors are discussed and the possible mechanisms for their thermal, photochemical and catalytic rearrangements are proposed. Conjugated organic polymers have been studied in the group since 1985 because of their potential for exhibiting high electroconductivity, photoconductivity, strong non-linear optical response and intense fluorescence. In the second section of this dissertation, the synthesis and property studies of poly(phenylene vinylene) analogues are discussed.

  10. Electrolyte Additives for Phosphoric Acid Fuel Cells

    DEFF Research Database (Denmark)

    Gang, Xiao; Hjuler, H.A.; Olsen, C.A.

    1993-01-01

    Electrochemical characteristics of a series of modified phosphoric acid electrolytes containing fluorinated car on compounds and silicone fluids as additives are presented. When used in phosphoric acid fuel cells, the modified electrolytes improve the performance due to the enhanced oxygen......, as a fuel-cell performance with the modified electrolytes. Specific conductivity measurements of some of the modified phosphoric acid electrolytes are reported. At a given temperature, the conductivity of the C4F9SO3K-modified electrolyte decreases with an increasing amount of the additive; the conductivity...... of the remains at the same value as the conductivity of the pure phosphoric acid. At a given composition, the conductivity of any modified electrolyte increases with temperature. We conclude that the improved cell performance for modified electrolytes is not due to any increase in conductivity....

  11. Laboratory tests of sludge-control additives

    Energy Technology Data Exchange (ETDEWEB)

    Tatnall, R.E. [MIC Associates, Inc., Chadds Ford, PA (United States)

    1996-07-01

    Laboratory {open_quotes}jar{close_quotes} tests compared eleven different fuel oil and diesel fuel sludge-control additives. Factors studied included (1) ability to disperse and prevent buildup of sludge deposits on surfaces, (2) ability to protect steel from corrosion, (3) ability to inhibit growth and proliferation of bacteria, and (4) ability to disperse water. Results varied greatly, and it was found that many commercial products do not do what they claim. It is concluded that fuel retailers should not believe manufacturers` claims for their additive products, but rather should test such products themselves to be sure that the benefits of treatment are real. A simplified form of the procedure used here is proposed as one way for dealers to do such testing.

  12. Rare Earth Additions in Continuously Cast Steel

    Science.gov (United States)

    Wilson, William G.; Heaslip, L. J.; Sommerville, I. D.

    1985-09-01

    Rare earth (lanthanide metals) addiiions to continuously cast steel are particularly advantageous because of their ability to refine as-cast structures, reduce segregation and increase hot ductility at temperatures just below that of solidification. The complete shape control of sulfides in steels containing Rare Earth Metals (REM), whether continuously cast or ingot cast, is primarily responsible for improvements in ductility related mechanical properties, weldability, fatigue resistance and resistance to hydrogen damage. Complete sulfide shape control can be obtained with REM additions at sulfur levels as high as.020%. The greatest improvements, however, are obtained with REM additions to low sulfur steels. However, to achieve full operational advantages afforded by REM, nozzle blockage problems must be circumvented. Water model studies indicate a possible solution.

  13. Femtosecond fiber laser additive manufacturing of tungsten

    Science.gov (United States)

    Bai, Shuang; Liu, Jian; Yang, Pei; Zhai, Meiyu; Huang, Huan; Yang, Lih-Mei

    2016-04-01

    Additive manufacturing (AM) is promising to produce complex shaped components, including metals and alloys, to meet requirements from different industries such as aerospace, defense and biomedicines. Current laser AM uses CW lasers and very few publications have been reported for using pulsed lasers (esp. ultrafast lasers). In this paper, additive manufacturing of Tungsten materials is investigated by using femtosecond (fs) fiber lasers. Various processing conditions are studied, which leads to desired characteristics in terms of morphology, porosity, hardness, microstructural and mechanical properties of the processed components. Fully dense Tungsten part with refined grain and increased hardness was obtained and compared with parts made with different pulse widths and CW laser. The results are evidenced that the fs laser based AM provides more dimensions to modify mechanical properties with controlled heating, rapid melting and cooling rates compared with a CW or long pulsed laser. This can greatly benefit to the make of complicated structures and materials that could not be achieved before.

  14. [Trends in the utilization of food additives].

    Science.gov (United States)

    Szűcs, Viktória; Bánáti, Diána

    2013-11-17

    The frequent media reports on food additives weakened consumers' trust in food producers and food control authorities as well. Furthermore, consumers' uncertainty is also raised by the fact that they obtain their information from inadequate, mistrustful sources and, therefore, consumers might avoid the consumption of certain foodstuffs. While food producers may react by replacing artificial components by natural ones, they try to emphasize the favourable characteristics of their products. The authors describe the main trends and efforts related to food additives. On the basis of the overview it can be concluded that - besides taking into consideration consumers' needs - product development and research directions are promising. Food producers' efforts may help to restore consumer confidence and trust and they may help them to have informed choice.

  15. The teratology testing of food additives.

    Science.gov (United States)

    Barrow, Paul C; Spézia, François

    2013-01-01

    The developmental and reproductive toxicity testing (including teratogenicity) of new foods and food additives is performed worldwide according to the guidelines given in the FDA Redbook. These studies are not required for substances that are generally recognized as safe, according to the FDA inventory. The anticipated cumulated human exposure level above which developmental or reproduction studies are required depends on the structure-alert category. For food additives of concern, both developmental (prenatal) and reproduction (multigeneration) studies are required. The developmental studies are performed in two species, usually the rat and the rabbit. The reproduction study is generally performed in the rat. The two rat studies are preferably combined into a single experimental design, if possible. The test methods described in the FDA Redbook are similar to those specified by the OECD for the reproductive toxicity testing of chemicals.

  16. Microbial biosurfactants as additives for food industries.

    Science.gov (United States)

    Campos, Jenyffer Medeiros; Stamford, Tânia Lúcia Montenegro; Sarubbo, Leonie Asfora; de Luna, Juliana Moura; Rufino, Raquel Diniz; Banat, Ibrahim M

    2013-01-01

    Microbial biosurfactants with high ability to reduce surface and interfacial surface tension and conferring important properties such as emulsification, detergency, solubilization, lubrication and phase dispersion have a wide range of potential applications in many industries. Significant interest in these compounds has been demonstrated by environmental, bioremediation, oil, petroleum, food, beverage, cosmetic and pharmaceutical industries attracted by their low toxicity, biodegradability and sustainable production technologies. Despite having significant potentials associated with emulsion formation, stabilization, antiadhesive and antimicrobial activities, significantly less output and applications have been reported in food industry. This has been exacerbated by uneconomical or uncompetitive costing issues for their production when compared to plant or chemical counterparts. In this review, biosurfactants properties, present uses and potential future applications as food additives acting as thickening, emulsifying, dispersing or stabilising agents in addition to the use of sustainable economic processes utilising agro-industrial wastes as alternative substrates for their production are discussed.

  17. Sintering of magnesia: effect of additives

    Indian Academy of Sciences (India)

    Satyananda Behera; Ritwik Sarkar

    2015-10-01

    Effect of different additives, namely Cr2O3, Fe2O3 and TiO2, up to 2 wt% was studied on the sintering and microstructural developments of the chemically pure magnesia using the pressureless sintering technique between 1500 and 1600° C. Sintering was evaluated by per cent densification and microstructural developments were studied by electron microscopy and elemental distribution of the additives in the sintered products was also investigated for their distribution in the matrix. Cr2O3 and TiO2 were found to deteriorate the densification associated with grain growth. Fe2O3 was found to improve the densification and well-compacted grain distribution was observed in the microstructure.

  18. An Additive Definition of Molecular Complexity.

    Science.gov (United States)

    Böttcher, Thomas

    2016-03-28

    A framework for molecular complexity is established that is based on information theory and consistent with chemical knowledge. The resulting complexity index Cm is derived from abstracting the information content of a molecule by the degrees of freedom in the microenvironments on a per-atom basis, allowing the molecular complexity to be calculated in a simple and additive way. This index allows the complexity of any molecule to be universally assessed and is sensitive to stereochemistry, heteroatoms, and symmetry. The performance of this complexity index is evaluated and compared against the current state of the art. Its additive character gives consistent values also for very large molecules and supports direct comparisons of chemical reactions. Finally, this approach may provide a useful tool for medicinal chemistry in drug design and lead selection, as demonstrated by correlating molecular complexities of antibiotics with compound-specific parameters.

  19. Modifying network connectivity with a subgraph addition

    CERN Document Server

    Taylor, Dane

    2011-01-01

    The principal eigenvalue $\\lambda$ of a network's adjacency matrix often determines dynamics on the network (e.g., in synchronization and spreading processes) and some of its structural properties (e.g., robustness against failure or attack), and is therefore a good indicator for how "strongly" a network is connected. We study how $\\lambda$ is modified by the addition of a subgraph. This type of modification has broad applications, ranging from those involving a single modification (e.g., introduction of a drug into a biological process) to those involving repeated subnetwork additions (e.g., power-grid and transit development). We describe how to optimally connect the subgraph to the network to either maximize or minimize the shift in $\\lambda$, noting several applications.

  20. [Additive Manufacturing and Its Medical Applications].

    Science.gov (United States)

    Song, Zewen; Wang, Guohui; Gao, Qin; Zhu, Shaihong

    2015-04-01

    Additive manufacturing (AM) is a collection of technologies based on the layer-by-layer manufacturing. Characterized by its direct manufacturing and rapidity, it has been regarded by the Economist Journal as one of the key techniques which will trigger the third industry reformation. The present article, beginning with a brief introduction of the history of AM and the process of its major technologies, focuses on the advantages and disadvantages and medical applications of the technique.

  1. Additive Manufacturing for Affordable Rocket Engines

    Science.gov (United States)

    West, Brian; Robertson, Elizabeth; Osborne, Robin; Calvert, Marty

    2016-01-01

    Additive manufacturing (also known as 3D printing) technology has the potential to drastically reduce costs and lead times associated with the development of complex liquid rocket engine systems. NASA is using 3D printing to manufacture rocket engine components including augmented spark igniters, injectors, turbopumps, and valves. NASA is advancing the process to certify these components for flight. Success Story: MSFC has been developing rocket 3D-printing technology using the Selective Laser Melting (SLM) process. Over the last several years, NASA has built and tested several injectors and combustion chambers. Recently, MSFC has 3D printed an augmented spark igniter for potential use the RS-25 engines that will be used on the Space Launch System. The new design is expected to reduce the cost of the igniter by a factor of four. MSFC has also 3D printed and tested a liquid hydrogen turbopump for potential use on an Upper Stage Engine. Additive manufacturing of the turbopump resulted in a 45% part count reduction. To understanding how the 3D printed parts perform and to certify them for flight, MSFC built a breadboard liquid rocket engine using additive manufactured components including injectors, turbomachinery, and valves. The liquid rocket engine was tested seven times in 2016 using liquid oxygen and liquid hydrogen. In addition to exposing the hardware to harsh environments, engineers learned to design for the new manufacturing technique, taking advantage of its capabilities and gaining awareness of its limitations. Benefit: The 3D-printing technology promises reduced cost and schedule for rocket engines. Cost is a function of complexity, and the most complicated features provide the largest opportunities for cost reductions. This is especially true where brazes or welds can be eliminated. The drastic reduction in part count achievable with 3D printing creates a waterfall effect that reduces the number of processes and drawings, decreases the amount of touch

  2. Materials as additives for advanced lubrication

    Energy Technology Data Exchange (ETDEWEB)

    Pol, Vilas G.; Thackeray, Michael M.; Mistry, Kuldeep; Erdemir, Ali

    2016-09-13

    This invention relates to carbon-based materials as anti-friction and anti-wear additives for advanced lubrication purposes. The materials comprise carbon nanotubes suspended in a liquid hydrocarbon carrier. Optionally, the compositions further comprise a surfactant (e.g., to aid in dispersion of the carbon particles). Specifically, the novel lubricants have the ability to significantly lower friction and wear, which translates into improved fuel economies and longer durability of mechanical devices and engines.

  3. Additive manufacturing – a sustainable manufacturing route

    OpenAIRE

    Frăţilă Domniţa; Rotaru Horaţiu

    2017-01-01

    Additive Manufacturing (AM) technologies allow developing and manufacturing very complex shaped parts and functional products with a high level of customization, being a great alternative to Traditional Manufacturing (TM) methods like injection molding, die-casting or machining. Due to the importance of cleaner production in the field of manufacturing processes, sustainability of AM processes needs to be assessed in order to make easier its acceptance and implementation in the industry. Furth...

  4. Designing for Color in Additive Manufacturing

    DEFF Research Database (Denmark)

    Eiríksson, Eyþór Rúnar; Luongo, Andrea; Frisvad, Jeppe Revall

    2016-01-01

    In this paper we present a color design pipeline for 3D printed or additively manufactured parts. We demonstrate how to characterize and calibrate a commercial printer and how to obtain its forward and backward color transformation models. We present results from our assistive color design tool......, allowing for colorimetric accurate prints and visualization of the printed outcome, prior to print. Lastly, we demonstrate our pipeline by accurately reproducing a real physical object....

  5. Navy additive manufacturing: adding parts, subtracting steps

    OpenAIRE

    Cunningham, Victor; Schrader, Christopher A.; Young, James

    2015-01-01

    Approved for public release; distribution is unlimited This study examines additive manufacturing (AM) and describes its potential impact on the Navy’s Supply Chain Management processes. Included in the analysis is the implementation of 3D printing technology and how it could impact the Navy’s future procurement processes, specifically based on a conducted analysis of the automotive aerospace industry. Industry research and development has identified multiple dimensions of AM technology, i...

  6. Conferences on Combinatorial and Additive Number Theory

    CERN Document Server

    2014-01-01

    This proceedings volume is based on papers presented at the Workshops on Combinatorial and Additive Number Theory (CANT), which were held at the Graduate Center of the City University of New York in 2011 and 2012. The goal of the workshops is to survey recent progress in combinatorial number theory and related parts of mathematics. The workshop attracts researchers and students who discuss the state-of-the-art, open problems, and future challenges in number theory.

  7. Supplier Selection Using Weighted Utility Additive Method

    Science.gov (United States)

    Karande, Prasad; Chakraborty, Shankar

    2015-10-01

    Supplier selection is a multi-criteria decision-making (MCDM) problem which mainly involves evaluating a number of available suppliers according to a set of common criteria for choosing the best one to meet the organizational needs. For any manufacturing or service organization, selecting the right upstream suppliers is a key success factor that will significantly reduce purchasing cost, increase downstream customer satisfaction and improve competitive ability. The past researchers have attempted to solve the supplier selection problem employing different MCDM techniques which involve active participation of the decision makers in the decision-making process. This paper deals with the application of weighted utility additive (WUTA) method for solving supplier selection problems. The WUTA method, an extension of utility additive approach, is based on ordinal regression and consists of building a piece-wise linear additive decision model from a preference structure using linear programming (LP). It adopts preference disaggregation principle and addresses the decision-making activities through operational models which need implicit preferences in the form of a preorder of reference alternatives or a subset of these alternatives present in the process. The preferential preorder provided by the decision maker is used as a restriction of a LP problem, which has its own objective function, minimization of the sum of the errors associated with the ranking of each alternative. Based on a given reference ranking of alternatives, one or more additive utility functions are derived. Using these utility functions, the weighted utilities for individual criterion values are combined into an overall weighted utility for a given alternative. It is observed that WUTA method, having a sound mathematical background, can provide accurate ranking to the candidate suppliers and choose the best one to fulfill the organizational requirements. Two real time examples are illustrated to prove

  8. Additive Manufacturing: From Form to Function

    Science.gov (United States)

    2016-01-01

    AM into the role of logistics and sustainment creates three opportunities: • AM can be used to reverse engineer replacement parts for legacy...move additive manufacturing technology from form to function. In this way, AM can be increasingly used in military mission areas such as logistics ...agencies. The article begins by exploring the growth of AM within the military and then ventures into the role of AM in logistics and sustainment

  9. DEVELOPMENT OF A FUNCTIONAL FEED ADDITIVE

    Directory of Open Access Journals (Sweden)

    Lysenko Y. A.

    2016-01-01

    Full Text Available The new feed additives for animals based on milk whey, enriched with sprouting wheat, barley, maize grains and lactic-acid bacterium have been presented in this article. This study explores the possibility of combining the prebiotics ability of milk whey and sprouting grains with feed probiotic attributes of microbe to enhance gut health of animals and digestibility of the feed. Twelve variants of products were tested in the study using the microbial and physical-chemical approaches. All the assays showed high count of microorganism and high content of reducing sugar. The results of investigation indicate that selected feed additive show high quality. An additional point is that it contains useful organic acids (lactic, acetic and propionic acids and 2,1×109 colony-forming unit of probiotics microorganism that hold the concentration for 4 months. There are not yeast, must, coliform bacteria and Staphylococcus aureus in the developed functional feed product. It contributes to the normalization of the microflora of the gastrointestinal tract of animal, suppression of conditionally pathogenic and putrefactive microflora. The elaborated feed component will help to provide combined feed companies with accessible high-quality raw material

  10. The value of additional videorecordings on defecography

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Sung Ki; Choi, Sang Hee; Kim, Seung Hoon; Kim, Seung Kwon; Lim, Hyo Keun; Lee, Soon Jin; Kim, Bo Hyun [Sungkyunkwan Univ. College of Medicine, Seoul (Korea, Republic of)

    1998-12-01

    To determine the value of additional videorecording during defecography. Ninety-nine consecutive patients (20 males, 79 females;mean age:48 yrs) who between august 1996 and June 1997 had undergone defecography due to defecation difficulty were included in this study. In all patients, spot filming(at rest, during squeezing, during straining) and videorecording during defecography were simultaneously performed. Two radiologists retrospectively reviewed spot films and video images, analyzed discrepancies between the two methods, and reached a consensus. In 52% of patients (51/99), the results of the two examinations were discrepant. The most common finding was anterior rectocele (n=3D33), followed by spastic pelvic floor syndrome (n=3D16), rectal intussusception (n=3D5), posterior rectocele (n=3D3), mucosal prolapse (n=3D2), descending perineal syndrome (n=3D2), and rectal prolapse (n=3D1). All findings except spastic pelvic floor syndrome were additionally found on videorecording. Because videorecording during defecography showed additional findings in 52% of patients, it is a necessary procedure for the diagnosis and management of patients with defecation difficulty.=20.

  11. Laser Additive Manufacturing of Magnetic Materials

    Science.gov (United States)

    Mikler, C. V.; Chaudhary, V.; Borkar, T.; Soni, V.; Jaeger, D.; Chen, X.; Contieri, R.; Ramanujan, R. V.; Banerjee, R.

    2017-03-01

    While laser additive manufacturing is becoming increasingly important in the context of next-generation manufacturing technologies, most current research efforts focus on optimizing process parameters for the processing of mature alloys for structural applications (primarily stainless steels, titanium base, and nickel base alloys) from pre-alloyed powder feedstocks to achieve properties superior to conventionally processed counterparts. However, laser additive manufacturing or processing can also be applied to functional materials. This article focuses on the use of directed energy deposition-based additive manufacturing technologies, such as the laser engineered net shaping (LENS™) process, to deposit magnetic alloys. Three case studies are presented: Fe-30 at.%Ni, permalloys of the type Ni-Fe-V and Ni-Fe-Mo, and Fe-Si-B-Cu-Nb (derived from Finemet) alloys. All these alloys have been processed from a blend of elemental powders used as the feedstock, and their resultant microstructures, phase formation, and magnetic properties are discussed in this paper. Although these alloys were produced from a blend of elemental powders, they exhibited relatively uniform microstructures and comparable magnetic properties to those of their conventionally processed counterparts.

  12. Additive Manufacturing of Biomaterials, Tissues, and Organs.

    Science.gov (United States)

    Zadpoor, Amir A; Malda, Jos

    2017-01-01

    The introduction of additive manufacturing (AM), often referred to as three-dimensional (3D) printing, has initiated what some believe to be a manufacturing revolution, and has expedited the development of the field of biofabrication. Moreover, recent advances in AM have facilitated further development of patient-specific healthcare solutions. Customization of many healthcare products and services, such as implants, drug delivery devices, medical instruments, prosthetics, and in vitro models, would have been extremely challenging-if not impossible-without AM technologies. The current special issue of the Annals of Biomedical Engineering presents the latest trends in application of AM techniques to healthcare-related areas of research. As a prelude to this special issue, we review here the most important areas of biomedical research and clinical practice that have benefited from recent developments in additive manufacturing techniques. This editorial, therefore, aims to sketch the research landscape within which the other contributions of the special issue can be better understood and positioned. In what follows, we briefly review the application of additive manufacturing techniques in studies addressing biomaterials, (re)generation of tissues and organs, disease models, drug delivery systems, implants, medical instruments, prosthetics, orthotics, and AM objects used for medical visualization and communication.

  13. Additive Technology for EU Ecolabel Formulations

    Institute of Scientific and Technical Information of China (English)

    Eric Nehls; Tassilo Habereder; Edward Ng

    2009-01-01

    Currently, Bio -lubricants are still regarded as niche products. Within the global lubricant market, however, the ar-ea of environmentally acceptable fluids represents one of the fast growing markets with an estimated annual growth of more than 6% per year. This growth is supported by various market drivers such as legal regulations, public subsidies and the im-plementation of national or international labeling schemes.With the implementation of the European Ecolabel for lubricants in 2005, a common standard specifying ecological and performance requirements for Bio - lubricants was defined. Applying for the EU Ecolabel requires a comprehensive assess-ment, not only of the final formulation, but also of the additives used. Additives are required to meet specifications for oxi-dation and thermal stability, as well as to impart metal protection (of both steel and yellow metals), thus improving corro-sion protection and wear performance of the formulation. Therefore, it is challenging in terms of formulation technology to develop the right formulation that meets the technical specifications as well as the stringent requirements of the EU - Ecola-bel.The paper describes how, by using ester base fluids and additives currently available in the market, lubricants can be developed to meet the technical and eco - toxicological requirements of the EU - Ecolabel, approaching the performance lev-els of lubricants formulated with traditional base fluids.

  14. The Porosity of Additive Noise Sequences

    CERN Document Server

    Misra, Vinith

    2012-01-01

    Consider a binary additive noise channel with noiseless feedback. When the noise is a stationary and ergodic process $\\mathbf{Z}$, the capacity is $1-\\mathbb{H}(\\mathbf{Z})$ ($\\mathbb{H}(\\cdot)$ denoting the entropy rate). It is shown analogously that when the noise is a deterministic sequence $z^\\infty$, the capacity under finite-state encoding and decoding is $1-\\bar{\\rho}(z^\\infty)$, where $\\bar{\\rho}(\\cdot)$ is Lempel and Ziv's finite-state compressibility. This quantity is termed the \\emph{porosity} $\\underline{\\sigma}(\\cdot)$ of an individual noise sequence. A sequence of schemes are presented that universally achieve porosity for any noise sequence. These converse and achievability results may be interpreted both as a channel-coding counterpart to Ziv and Lempel's work in universal source coding, as well as an extension to the work by Lomnitz and Feder and Shayevitz and Feder on communication across modulo-additive channels. Additionally, a slightly more practical architecture is suggested that draws a...

  15. Bond additivity corrections for quantum chemistry methods

    Energy Technology Data Exchange (ETDEWEB)

    C. F. Melius; M. D. Allendorf

    1999-04-01

    In the 1980's, the authors developed a bond-additivity correction procedure for quantum chemical calculations called BAC-MP4, which has proven reliable in calculating the thermochemical properties of molecular species, including radicals as well as stable closed-shell species. New Bond Additivity Correction (BAC) methods have been developed for the G2 method, BAC-G2, as well as for a hybrid DFT/MP2 method, BAC-Hybrid. These BAC methods use a new form of BAC corrections, involving atomic, molecular, and bond-wise additive terms. These terms enable one to treat positive and negative ions as well as neutrals. The BAC-G2 method reduces errors in the G2 method due to nearest-neighbor bonds. The parameters within the BAC-G2 method only depend on atom types. Thus the BAC-G2 method can be used to determine the parameters needed by BAC methods involving lower levels of theory, such as BAC-Hybrid and BAC-MP4. The BAC-Hybrid method should scale well for large molecules. The BAC-Hybrid method uses the differences between the DFT and MP2 as an indicator of the method's accuracy, while the BAC-G2 method uses its internal methods (G1 and G2MP2) to provide an indicator of its accuracy. Indications of the average error as well as worst cases are provided for each of the BAC methods.

  16. Microbial analyses of cement and grouting additives

    Energy Technology Data Exchange (ETDEWEB)

    Hallbeck, L.; Jaegevall, S.; Paeaejaervi, A.; Rabe, L.; Edlund, J.; Eriksson, S. [Microbial Analytics Sweden AB, Moelnlycke (Sweden)

    2012-01-15

    During sampling in the ONKALO tunnel in 2006, heavy growth of a slimy material was observed in connection with grouting. It was suggested to be microbial growth on organic additives leaching from the grout. Two sampling campaigns resulted in the isolation of several aerobic bacterial strains. Some of these strains were used in biodegradation studies of three solid cement powders, eight liquid grout additives, and six plastic drainage materials. Degradation was also studied using ONKALO groundwaters as inoculums. The isolated strains were most closely related to hydrocarbon-degrading microorganisms. The biodegradation of seven of the products was tested using microorganisms isolated from the ONKALO slime in 2006; none of these strains could degrade the tested products. When ONKALO drillhole groundwaters were used as inoculums in the degradation studies, it was demonstrated that Structuro 111X, Mighty 150, and Super-Parmix supported growth of the groundwater microorganisms. Structuro 111X is a polycarboxylate condensate while Mighty 150 and Super-Parmix are condensates with formaldehyde and naphthalene. Some of the isolated microorganisms belonged to the genus Pseudomonas, many strains of which can degrade organic molecules. None of the plastic drainage materials supported growth during the degradation studies. Microorganisms were present in two of the liquid products when delivered, GroutAid and Super-Parmix. The potential of the organic compounds in grout additives to be degraded by microorganisms, increasing the risk of biofilm formation and complexing compound production, must be considered. Microbial growth will also increase the possibility of hydrogen sulphide formation. (orig.)

  17. 241镅跟骨骨密度测定在骨质疏松症中的初步应用 ——与腰椎骨密度测定的对比研究%Preliminary application of 241-Americium calcaneus bone mineral density measurement in osteoporosis ——comparison with double X-ray densitometry of the lumber spine

    Institute of Scientific and Technical Information of China (English)

    管梁; 朱承谟; 李培勇; 王辉; 濮鸣芳; 仇季高

    2001-01-01

    Bone mineral density (BMD) of calcaneus in 54 normals, 45 Osteoporosis, 25 suspected osteoporosis and 16 other non-osteoporosis patients, a total of 140 cases were measured by HUAKE (HK-1) 241-Americium BMD absorpmetry, among them 43 were compared with that of lumber spine (L2—L4) measured by Lunar Corporation's Expert-XL absorpmeter. BMD of normal group of calcaneus was (409.8±79.4)mg/cm2. The BMD were decreased slowly with the increased age. The BMD of osteoporosis, suspected osteoporosis and non-osteoporosis group were 230.3±62.3, 395.7±57.4 and 363.3±51.9mg/cm2 respectively. The BMD of osteoporosis group was much lower than that of normal group, and also lower than that of the other two groups, among 26 patients (57.78%) had bone fracture, all was in accordance with the clinical diagnosis of osteoporosis. The BMD of suspected ospteoporosis and non-osteoporosis had no significant difference with normal group. The coefficient variation (CV) of BMD in repeated measurement in calcaneus of 4 pariticipants was less than 1.2%. The correlative coefficient (r) between BMD of calcaneus and lumber spine (L2—L4) group was 0.6824. The correlative coefficient of normal young adult-matched percentage and T value in 2 groups were 0.6863 and 0.6755 respectively, whereas aged-matched percentage, Z value were 0.4614 and 0.5009 respectively. In conclusion 241-Americium calcaneus BMD absorpmetry has the advantage of low price, easy to operate, reliable and valuable in diagnosis osteoporosis. The correlations of calcaneus and lumber spine BMD, normal young adult-matched percentagy and T value were rather good.%为评价跟骨骨密度测定在骨质疏松症中的初步临床应用及与腰椎测定结果的相关性,用国产华科(HK-1型)241镅骨密度仪测定了140例跟骨骨密度(BMD)。其中正常人组54例,骨质疏松确诊组45例,骨质疏松可疑组25例和其他非骨质疏松组16例。其中43例与美国Luner 公司的Expert-XL图像骨密度仪腰

  18. Improvements in China's Food Additive Laws-Fermented Flour Paste Additive in Beijing Roast Duck

    Institute of Scientific and Technical Information of China (English)

    Wang Jianglian; Zhao Xin

    2008-01-01

    About half of the food safety incidents in 2005 and 2006 were related to food additives. Early in 2007,the main problem for administrative enforcement is the issue of food additives.This paper analyzes one such incident:the fermented flour paste incident in Beijing roast duck that occurred in early 2007.We put forward suggested ways to perfect the legal system regarding Chinese food additives by focusing on legal and management mechanisms.This includes optimizing higher-level laws for food additives,improving the standards system,cultivating the appropriate concepts,implementing preventive measures,and facilitating routine law enforcement.

  19. Mechanical properties of additively manufactured octagonal honeycombs.

    Science.gov (United States)

    Hedayati, R; Sadighi, M; Mohammadi-Aghdam, M; Zadpoor, A A

    2016-12-01

    Honeycomb structures have found numerous applications as structural and biomedical materials due to their favourable properties such as low weight, high stiffness, and porosity. Application of additive manufacturing and 3D printing techniques allows for manufacturing of honeycombs with arbitrary shape and wall thickness, opening the way for optimizing the mechanical and physical properties for specific applications. In this study, the mechanical properties of honeycomb structures with a new geometry, called octagonal honeycomb, were investigated using analytical, numerical, and experimental approaches. An additive manufacturing technique, namely fused deposition modelling, was used to fabricate the honeycomb from polylactic acid (PLA). The honeycombs structures were then mechanically tested under compression and the mechanical properties of the structures were determined. In addition, the Euler-Bernoulli and Timoshenko beam theories were used for deriving analytical relationships for elastic modulus, yield stress, Poisson's ratio, and buckling stress of this new design of honeycomb structures. Finite element models were also created to analyse the mechanical behaviour of the honeycombs computationally. The analytical solutions obtained using Timoshenko beam theory were close to computational results in terms of elastic modulus, Poisson's ratio and yield stress, especially for relative densities smaller than 25%. The analytical solutions based on the Timoshenko analytical solution and the computational results were in good agreement with experimental observations. Finally, the elastic properties of the proposed honeycomb structure were compared to those of other honeycomb structures such as square, triangular, hexagonal, mixed, diamond, and Kagome. The octagonal honeycomb showed yield stress and elastic modulus values very close to those of regular hexagonal honeycombs and lower than the other considered honeycombs.

  20. The addition of iodine to tetramethylammonium iodide

    Science.gov (United States)

    Foote, H.W.; Fleischer, M.

    1953-01-01

    The system tetramethylammonium iodide-iodine-toluene has been studied by the solubility method at 6 and at 25??. The compounds (CH3)4NI3, (CH3)4NI5 and (CH3)4NI11 were found to be stable phases at both temperatures. In addition, the compound (CH3)4NI10 was found at 6?? and the compound (CH3)4NI9 at 25??. The dissociation pressures of the compounds at these temperatures were calculated from the solubility data.

  1. Additive manufacturing – a sustainable manufacturing route

    Directory of Open Access Journals (Sweden)

    Frăţilă Domniţa

    2017-01-01

    Full Text Available Additive Manufacturing (AM technologies allow developing and manufacturing very complex shaped parts and functional products with a high level of customization, being a great alternative to Traditional Manufacturing (TM methods like injection molding, die-casting or machining. Due to the importance of cleaner production in the field of manufacturing processes, sustainability of AM processes needs to be assessed in order to make easier its acceptance and implementation in the industry. Furthermore, the manufacturers can improve their competitiveness and profitability by considering the ecological aspects during the manufacturing step of a product. This paper gives a survey on sustainability issues related to AM.

  2. Additive Manufacturing of Hierarchical Porous Structures

    Energy Technology Data Exchange (ETDEWEB)

    Grote, Christopher John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Materials Science and Technology Division. Polymers and Coatings

    2016-08-30

    Additive manufacturing has become a tool of choice for the development of customizable components. Developments in this technology have led to a powerful array of printers that t serve a variety of needs. However, resin development plays a crucial role in leading the technology forward. This paper addresses the development and application of printing hierarchical porous structures. Beginning with the development of a porous scaffold, which can be functionalized with a variety of materials, and concluding with customized resins for metal, ceramic, and carbon structures.

  3. Dust-Firing of Straw and Additives

    DEFF Research Database (Denmark)

    Wu, Hao; Glarborg, Peter; Frandsen, Flemming;

    2011-01-01

    In the present work, the ash chemistry and deposition behavior during straw dust-firing were studied by performing experiments in an entrained flow reactor. The effect of using spent bleaching earth (SBE) as an additive in straw combustion was also investigated by comparing with kaolinite. During...... dust-firing of straw, the large (>∼2.5 μm) fly ash particles generated were primarily molten or partially molten spherical particles rich in K, Si, and Ca, supplemented by Si-rich flake-shaped particles. The smaller fly ash particles (...

  4. Custom surgical implants using additive manufacturing

    OpenAIRE

    POUKENS, Jules; Laeven, Paul; BEERENS, Maikel; Koper, David; Lethaus, Bernd; Kessler, Peter; Vander Sloten, Jos; Lambrichts, Ivo

    2010-01-01

    CAD/CAM and Additive Manufacturing (AM) are getting more attention in the medical sector, especially in cranio-maxillofacial surgery where defects of the face (e.g., absence of a nose, ear, or eye) have a very big psycho-social impact. Radiological, optical, and laser scans of the patient are converted into a virtual three-dimensional patient with subsequent virtual design of the medical device. AM methods enable the production of custom implants made in a solid or resorbable material, or eve...

  5. Influence of Additives on Reinforced Concrete Durability

    Directory of Open Access Journals (Sweden)

    Neverkovica Darja

    2014-12-01

    Full Text Available The article presents the results of the research on carbonation and chloride induced corrosion mechanisms in reinforced concrete structures, based on three commercially available concrete admixtures: Xypex Admix C-1000, Penetron Admix and Elkem Microsilica. Carbonation takes place due to carbon dioxide diffusion, which in the required amount is present in the air. Chlorides penetrate concrete in case of the use of deicing salt or structure exploitation in marine atmosphere. Based on the implemented research, Elkem Microsilica is the recommended additive for the use in aggressive environmental conditions. Use of Xypex Admix C-1000 and Penetron Admix have only average resistance to the aggressive environmental impact.

  6. 10 conjectures in additive number theory

    CERN Document Server

    Cloitre, Benoit

    2011-01-01

    Following an idea of Rowland we give a conjectural way to generate increasing sequences of primes using algorithms involving the gcd. These algorithms seem not so useless for searching primes since it appears we found sometime primes much more greater than the number of required iterations. In an other hand we propose new formulations of famous conjectures from the additive theory of numbers (the weak twin prime conjecture, the Polignac conjecture, the Goldbach conjecture or the very general Schinzel's hypothesis H). For the moment these are experimental results obtained using pari-gp.

  7. MIXED HEDGING UNDER ADDITIVE MARKET PRICE INFORMATION

    Institute of Scientific and Technical Information of China (English)

    Haifeng YAN; Jianqi YANG; Limin LIU

    2008-01-01

    Assume that there is additional market information in the financial market, which is represented by n given T-contingent claims. The special claims with observed prices at time 0 can only be traded at time 0. Hence, investment opportunities increase. By means of the techniques developed by Gourierout et al. (1998), the mixed hedging problem is considered, especially, the price of contingent claim and the optimal hedging strategy are obtained. An explicit description of the mean-variance efficient solution is given after arguing mean-variance efficient frontier problem.

  8. Structural dynamic modification using additive damping

    Indian Academy of Sciences (India)

    B C Nakra

    2000-06-01

    In order to control dynamic response in structures and machines, modofications using additive viscoelastic damping materials are highlighted. The techniques described for analysis include analytical methods for structural elements, FEM and perturbation methods for reanalysis or structural dynamic modifications for complex structures. Optimisation techniques are used for damping effectiveness include multi-parameter optimisatoin techniques and a technique using dynamic sensitivity analysis and structural dynamic modification. These have been applied for optimum dynamic design of structures incorporating viscoelastic damping. Some current trends for vibraton control are also discussed.

  9. Mechanism and kinetics of addition polymerizations

    CERN Document Server

    Kucera, M

    1991-01-01

    This volume presents an up-to-date survey of knowledge concerning addition type polymerizations. It contains nine chapters, each of which covers a particular basic term. Whenever necessary, the phenomena are discussed from the viewpoint of both stationary and non-stationary state of radical, ionic (i.e. anionic and cationic) and coordination polymerization. Special attention has been paid to the propagation process. It provides not only a general overview but also information on important special cases (theoretical conditions of propagation, influence of external factors, controlled propagatio

  10. Characteristics of asphalt mixes with FT additive

    Science.gov (United States)

    Štefunková, S.

    2012-03-01

    This article is focused on low-temperature asphalt mixture technologies using FT additive and RAP. The modern production and use of asphalt mixture technologies with reduced temperatures has many advantages. These advantages mainly help to save energy and the environment. Lower temperatures enable a reduction in energy consumption, a more acceptable working environment for workers, a reduction in negative environmental effects, such as greenhouse gas emissions, and an improvement in the workability of mixtures and a prolongation of their duration. This technology is currently becoming popular in many countries.

  11. Energy additivity in branched and cyclic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Gao, H.; Bader, R.F.W. [McMaster Univ., Hamilton, ON (Canada). Dept. of Chemistry; Cortes-Guzman, F. [Univ. Nacional Autonoma de Mexico, (Mexico). Dept. de Fisicoquimica

    2009-11-15

    This paper reported on a study of the energetic relationships between hydrocarbon molecules and the heats of formation. The quantum theory of atoms in molecules (QTAIM) was used to investigate the degree to which branched hydrocarbons obey a group additivity scheme for energy and populations. The QTAIM defined the properties of the chemical groups. The experimental and theoretical transferability of the methyl and methylene groups of the linear hydrocarbons was also explored. The calculations were performed using a large basis set at the restricted Hartree-Fock and MP2(full) levels of theory. The study also investigated the deviations from additivity, noted for small ring hydrocarbons leading to the definition of strain energy. The QTAIM energies recovered the experimental values. The paper included details regarding the delocalization of the electron density over the surface of the cyclopropane ring, responsible for its homoaromatic properties. The calculations presented in this study satisfied the virial theorem for the atomic definition of energy. The paper discussed the problems associated with the use of the density functional theory (DFT) resulting from its failure to satisfy the virial theorem. 44 refs., 9 tabs., 2 figs.

  12. Value addition to bamboo shoots: a review.

    Science.gov (United States)

    Choudhury, Debangana; Sahu, Jatindra K; Sharma, G D

    2012-08-01

    Bamboo shoot forms a traditional delicacy in many countries. Being low in fat content and high in potassium, carbohydrate, dietary fibres, Vitamins and active materials, bamboo shoots are consumed in raw, canned, boiled, marinated, fermented, frozen, liquid and medicinal forms. Although the fresh bamboo shoots of species like Dendraocalamus giganteus are healthier and nutritionally rich, the young shoots, after fortification, can be consumed by processing into a wide range of food products with longer shelf-life and better organoleptic qualities. However, the consumption pattern of bamboo shoots in most of the countries is traditional, non-standardized, seasonal and region-specific with little value addition. Therefore, there exists a great opportunity, especially for the organized food processing sectors to take up the processing of bamboo shoot-based food products in an organized manner. The present article gives an insight into the global scenario of bamboo shoot-based food products and their consumption pattern, the quality attributes, and the opportunities for value addition along with future prospects in view of international food safety, security and nutrition.

  13. Additive and Photochemical Manufacturing of Copper

    Science.gov (United States)

    Yung, Winco K. C.; Sun, Bo; Meng, Zhengong; Huang, Junfeng; Jin, Yingdi; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

    2016-12-01

    In recent years, 3D printing technologies have been extensively developed, enabling rapid prototyping from a conceptual design to an actual product. However, additive manufacturing of metals in the existing technologies is still cost-intensive and time-consuming. Herein a novel platform for low-cost additive manufacturing is introduced by simultaneously combining the laser-induced forward transfer (LIFT) method with photochemical reaction. Using acrylonitrile butadiene styrene (ABS) polymer as the sacrificial layer, sufficient ejection momentum can be generated in the LIFT method. A low-cost continuous wave (CW) laser diode at 405 nm was utilized and proved to be able to transfer the photochemically synthesized copper onto the target substrate. The wavelength-dependent photochemical behaviour in the LIFT method was verified and characterized by both theoretical and experimental studies compared to 1064 nm fiber laser. The conductivity of the synthesized copper patterns could be enhanced using post electroless plating while retaining the designed pattern shapes. Prototypes of electronic circuits were accordingly built and demonstrated for powering up LEDs. Apart from pristine PDMS materials with low surface energies, the proposed method can simultaneously perform laser-induced forward transfer and photochemical synthesis of metals, starting from their metal oxide forms, onto various target substrates such as polyimide, glass and thermoplastics.

  14. Emerging technologies in arthroplasty: additive manufacturing.

    Science.gov (United States)

    Banerjee, Samik; Kulesha, Gene; Kester, Mark; Mont, Michael A

    2014-06-01

    Additive manufacturing is an industrial technology whereby three-dimensional visual computer models are fabricated into physical components by selectively curing, depositing, or consolidating various materials in consecutive layers. Although initially developed for production of simulated models, the technology has undergone vast improvements and is currently increasingly being used for the production of end-use components in various aerospace, automotive, and biomedical specialties. The ability of this technology to be used for the manufacture of solid-mesh-foam monolithic and coated components of complex geometries previously considered unmanufacturable has attracted the attention of implant manufacturers, bioengineers, and orthopedic surgeons. Currently, there is a paucity of reports describing this fabrication method in the orthopedic literature. Therefore, we aimed to briefly describe this technology, some of the applications in other orthopedic subspecialties, its present use in hip and knee arthroplasty, and concerns with the present form of the technology. As there are few reports of clinical trials presently available, the true benefits of this technology can only be realized when studies evaluating the clinical and radiographic outcomes of cementless implants manufactured with additive manufacturing report durable fixation, less stress shielding, and better implant survivorship. Nevertheless, the authors believe that this technology holds great promise and may potentially change the conventional methods of casting, machining, and tooling for implant manufacturing in the future.

  15. The Electrophilic Addition to Alkynes Revisited

    Science.gov (United States)

    Tidwell, Thomas T.

    1996-11-01

    A recent claim (Weiss, H. J. Chem. Ed. 1993, 70, 873 - 874) that vinyl cations are not the predominant intermediates in the electrophilic addition to alkynes in disputed on the following grounds: (1) these is a linear free energy correlation between the rates of acid-catalyzed hydration of alkenes and alkynes, and since carbocations are accepted as intermediates in the former reaction, they are implicated in the latter as well; (2) rearrangements are known to be energetically less favorable in vinyl cations compared to alkyl cations, and so the lesser observed tendency for rearrangement in the former case does not argue for the absence of vinyl cation intermediates; (3) there is evidence that alkenes and alkynes react with HBr and HCl in some cases with anti addition and a kinetic term in [HX]2, but this is not an argument for a difference in behavior between the two, or for a pi-complex mechanism; (4) thermochemical calculations show that vinyl cations are not prohbitively destabilized compared to analogous alkyl cations; (5) the observation of an HCl/acetylene pi-complex in the gas phase is not an argument that this represents a rate-limiting transition state in solution.

  16. Additive manufacturing of glass for optical applications

    Science.gov (United States)

    Luo, Junjie; Gilbert, Luke J.; Bristow, Douglas A.; Landers, Robert G.; Goldstein, Jonathan T.; Urbas, Augustine M.; Kinzel, Edward C.

    2016-04-01

    Glasses including fused quartz have significant scientific and engineering applications including optics, communications, electronics, and hermetic seals. This paper investigates a filament fed process for Additive Manufacturing (AM) of fused quartz. Additive manufacturing has several potential benefits including increased design freedom, faster prototyping, and lower processing costs for small production volumes. However, current research in AM of glasses is limited and has focused on non-optical applications. Fused quartz is studied here because of its desirability for high-quality optics due to its high transmissivity and thermal stability. Fused quartz also has a higher working temperature than soda lime glass which poses a challenge for AM. In this work, fused quartz filaments are fed into a CO2 laser generated melt pool, smoothly depositing material onto the work piece. Single tracks are printed to explore the effects that different process parameters have on the morphology of printed fused quartz. A spectrometer is used to measure the thermal radiation incandescently emitted from the melt pool. Thin-walls are printed to study the effects of layer-to-layer height. Finally, a 3D fused quartz cube is printed using the newly acquired layer height and polished on each surface. The transmittance and index homogeneity of the polished cube are both measured. These results show that the filament fed process has the potential to print fused quartz with optical transparency and of index of refraction uniformity approaching bulk processed glass.

  17. Gas hydrate inhibition of drilling fluid additives

    Energy Technology Data Exchange (ETDEWEB)

    Xiaolan, L.; Baojiang, S.; Shaoran, R. [China Univ. of Petroleum, Dongying (China). Inst. of Petroleum Engineering

    2008-07-01

    Gas hydrates that form during offshore well drilling can have adverse impacts on well operational safety. The hydrates typically form in the risers and the annulus between the casing and the drillstring, and can stop the circulation of drilling fluids. In this study, experiments were conducted to measure the effect of drilling fluid additives on hydrate inhibition. Polyalcohols, well-stability control agents, lubricating agents, and polymeric materials were investigated in a stirred tank reactor at temperatures ranging from -10 degree C to 60 degrees C. Pressure, temperature, and torque were used to detect onset points of hydrate formation and dissociation. The inhibitive effect of the additives on hydrate formation was quantified. Phase boundary shifts were measured in terms of temperature difference or sub-cooling gained when chemicals were added to pure water. Results showed that the multiple hydroxyl groups in polyalcohol chemicals significantly inhibited hydrate formation. Polymeric and polyacrylamide materials had only a small impact on hydrate formation, while sulfonated methyl tannins were found to increase hydrate formation. 6 refs., 1 tab., 4 figs.

  18. 76 FR 16285 - Food Additives Permitted for Direct Addition to Food for Human Consumption; Bacteriophage...

    Science.gov (United States)

    2011-03-23

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 172 (formerly Docket No. 2002F-0316) Food Additives Permitted for Direct Addition to Food for Human Consumption; Bacteriophage Preparation AGENCY: Food and Drug Administration, HHS. ACTION: Final rule; response to objections and denial of...

  19. 76 FR 41687 - Food Additives Permitted for Direct Addition to Food for Human Consumption; Hydroxypropyl Cellulose

    Science.gov (United States)

    2011-07-15

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 172 Food Additives Permitted for Direct Addition to Food for Human Consumption; Hydroxypropyl Cellulose AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the food...

  20. The retro Grignard addition reaction revisited: the reversible addition of benzyl reagents to ketones

    DEFF Research Database (Denmark)

    Christensen, Stig Holden; Holm, Torkil; Madsen, Robert

    2014-01-01

    The Grignard addition reaction is known to be a reversible process with allylic reagents, but so far the reversibility has not been demonstrated with other alkylmagnesium halides. By using crossover experiments it has been established that the benzyl addition reaction is also a reversible transfo...

  1. Additive functionals and excursions of Kuznetsov processes

    Directory of Open Access Journals (Sweden)

    Hacène Boutabia

    2005-01-01

    semigroup of transition. In this paper, we give the excursion laws of (Xtt∈ℝ+ conditioned on the strict past and future without duality hypothesis. We study excursions of a general regenerative system and of a regenerative system consisting of the closure of the set of times the regular points of B are visited. In both cases, those conditioned excursion laws depend only on two points Xg− and Xd, where ]g,d[ is an excursion interval of the regenerative set M. We use the (FDt-predictable exit system to bring together the isolated points of M and its perfect part and replace the classical optional exit system. This has been a subject in literature before (e.g., Kaspi (1988 under the classical duality hypothesis. We define an “additive functional” for (Ytt∈ℝ with B, we generalize the laws cited before to (Ytt∈ℝ, and we express laws of pairs of excursions.

  2. The stability of alloying additions in Zirconium

    Energy Technology Data Exchange (ETDEWEB)

    Lumley, S.C. [Department of Materials, Imperial College, London, SW7 2AZ (United Kingdom); Nuclear Department, Defence Academy, HMS Sultan, Gosport, Hampshire, PO12 3BY (United Kingdom); Murphy, S.T. [Department of Materials, Imperial College, London, SW7 2AZ (United Kingdom); Burr, P.A. [Department of Materials, Imperial College, London, SW7 2AZ (United Kingdom); Institute of Materials Engineering, Australian Nuclear Science and Technology Organisation, Menai, New South Wales 2234 (Australia); Grimes, R.W. [Department of Materials, Imperial College, London, SW7 2AZ (United Kingdom); Chard-Tuckey, P.R. [Nuclear Department, Defence Academy, HMS Sultan, Gosport, Hampshire, PO12 3BY (United Kingdom); Wenman, M.R., E-mail: m.wenman@imperial.ac.uk [Department of Materials, Imperial College, London, SW7 2AZ (United Kingdom)

    2013-06-15

    The interactions of Cr, Fe, Nb, Ni, Sn, V and Y with Zr are simulated using density functional theory. Thermodynamic stabilities of various different Zr based intermetallic compounds, including multiple Laves phase structures and solutions of alloying additions in both α and β-Zr were investigated. The thermodynamic driving forces in this system can be correlated with trends in atomic radii and the relative electronegativities of the different species. Formation energies of Fe, Ni and Sn based intermetallic compounds were found to be negative, and the Zr{sub 2}Fe and Zr{sub 2}Ni intermetallics were metastable. Most elements displayed negative energies of solution in β-Zr but positive energies in the α-phase, with the exception of Sn (which was negative for both) and Y (which was positive for both). Solutions formed from intermetallics showed a similar trend.

  3. Atom addition reactions in interstellar ice analogues

    CERN Document Server

    Linnartz, Harold; Fedoseev, Gleb

    2015-01-01

    This review paper summarizes the state-of-the-art in laboratory based interstellar ice chemistry. The focus is on atom addition reactions, illustrating how water, carbon dioxide and methanol can form in the solid state at astronomically relevant temperatures, and also the formation of more complex species such as hydroxylamine, an important prebiotic molecule, and glycolaldehyde, the smallest sugar, is discussed. These reactions are particularly relevant during the dark ages of star and planet formation, i.e., when the role of UV light is restricted. A quantitative characterization of such processes is only possible through dedicated laboratory studies, i.e., under full control of a large set of parameters such as temperature, atom-flux, and ice morphology. The resulting numbers, physical and chemical constants, e.g., barrier heights, reaction rates and branching ratios, provide information on the molecular processes at work and are needed as input for astrochemical models, in order to bridge the timescales t...

  4. Additive Feed Forward Control with Neural Networks

    DEFF Research Database (Denmark)

    Sørensen, O.

    1999-01-01

    This paper demonstrates a method to control a non-linear, multivariable, noisy process using trained neural networks. The basis for the method is a trained neural network controller acting as the inverse process model. A training method for obtaining such an inverse process model is applied....... A suitable 'shaped' (low-pass filtered) reference is used to overcome problems with excessive control action when using a controller acting as the inverse process model. The control concept is Additive Feed Forward Control, where the trained neural network controller, acting as the inverse process model......, is placed in a supplementary pure feed-forward path to an existing feedback controller. This concept benefits from the fact, that an existing, traditional designed, feedback controller can be retained without any modifications, and after training the connection of the neural network feed-forward controller...

  5. Printability of alloys for additive manufacturing.

    Science.gov (United States)

    Mukherjee, T; Zuback, J S; De, A; DebRoy, T

    2016-01-22

    Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is used to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. The findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts.

  6. Combined additive manufacturing approaches in tissue engineering.

    Science.gov (United States)

    Giannitelli, S M; Mozetic, P; Trombetta, M; Rainer, A

    2015-09-01

    Advances introduced by additive manufacturing (AM) have significantly improved the control over the microarchitecture of scaffolds for tissue engineering. This has led to the flourishing of research works addressing the optimization of AM scaffolds microarchitecture to optimally trade-off between conflicting requirements (e.g. mechanical stiffness and porosity level). A fascinating trend concerns the integration of AM with other scaffold fabrication methods (i.e. "combined" AM), leading to hybrid architectures with complementary structural features. Although this innovative approach is still at its beginning, significant results have been achieved in terms of improved biological response to the scaffold, especially targeting the regeneration of complex tissues. This review paper reports the state of the art in the field of combined AM, posing the accent on recent trends, challenges, and future perspectives.

  7. Additive manufacturing of biologically-inspired materials.

    Science.gov (United States)

    Studart, André R

    2016-01-21

    Additive manufacturing (AM) technologies offer an attractive pathway towards the fabrication of functional materials featuring complex heterogeneous architectures inspired by biological systems. In this paper, recent research on the use of AM approaches to program the local chemical composition, structure and properties of biologically-inspired materials is reviewed. A variety of structural motifs found in biological composites have been successfully emulated in synthetic systems using inkjet-based, direct-writing, stereolithography and slip casting technologies. The replication in synthetic systems of design principles underlying such structural motifs has enabled the fabrication of lightweight cellular materials, strong and tough composites, soft robots and autonomously shaping structures with unprecedented properties and functionalities. Pushing the current limits of AM technologies in future research should bring us closer to the manufacturing capabilities of living organisms, opening the way for the digital fabrication of advanced materials with superior performance, lower environmental impact and new functionalities.

  8. Organic Additive Implantation onto Cement Hydration Products

    Institute of Scientific and Technical Information of China (English)

    ZHU Jipeng; LI Zongjin; YANG Ruochong; ZHANG Yamei

    2014-01-01

    In polymer modified cementitious materials, it is hard to set up a chemical connection between the added polymer and the cement moiety. In this study FS (functional silane) was adopted to form this connection as a bridge component which has the functional group forming bonds with polymer. To testify the connection between FS and cement moiety, Q2/Q1 ratio (Qx:intensity ratio) investigation was carried out by the means of quantitative solid state 29Si MAS NMR. The results show that the Q2/Q1 ratio has increased with the addition of FS which indicates that the silicon chain length has increased, and the quantity of silicon atoms at site of Q2, chain site, has enhanced, showing that the silicon atom of FS has connected to the silicon chain of cement moiety by the bond“-Si-O-Si-”formation.

  9. Subgroup finding via Bayesian additive regression trees.

    Science.gov (United States)

    Sivaganesan, Siva; Müller, Peter; Huang, Bin

    2017-03-09

    We provide a Bayesian decision theoretic approach to finding subgroups that have elevated treatment effects. Our approach separates the modeling of the response variable from the task of subgroup finding and allows a flexible modeling of the response variable irrespective of potential subgroups of interest. We use Bayesian additive regression trees to model the response variable and use a utility function defined in terms of a candidate subgroup and the predicted response for that subgroup. Subgroups are identified by maximizing the expected utility where the expectation is taken with respect to the posterior predictive distribution of the response, and the maximization is carried out over an a priori specified set of candidate subgroups. Our approach allows subgroups based on both quantitative and categorical covariates. We illustrate the approach using simulated data set study and a real data set. Copyright © 2017 John Wiley & Sons, Ltd.

  10. Experimental Investigation of Using Fuel Additives - Alcohol

    Directory of Open Access Journals (Sweden)

    S.M. Fayyad

    2010-03-01

    Full Text Available This research presents an investigation of the effects of ethanol addition to low octane numbergasoline, on the fuel octane number and on the performance of the engine. In this study, the tested gasoline(octane number = 90 is blended with five different percentages of ethanol, namely 3, 6, 9, 12 and 15% onvolume basis. Then these fuel blends, as well as the base gasoline fuel, w ere burnt in the tested engine. It isfound that the octane number of gasoline increases continuously and linearly with increasing the ethanolpercentage in gasoline. Hence, ethanol is an effective compound for increasing the value of the octane numberof gasoline. Also, it is also noticed that the best performance of the engine was obtained when 15% of ethanolwas used in the gasoline blend.

  11. A DNA based model for addition computation

    Institute of Scientific and Technical Information of China (English)

    GAO Lin; YANG Xiao; LIU Wenbin; XU Jin

    2004-01-01

    Much effort has been made to solve computing problems by using DNA-an organic simulating method, which in some cases is preferable to the current electronic computer. However, No one at present has proposed an effective and applicable method to solve addition problem with molecular algorithm due to the difficulty in solving the carry problem which can be easily solved by hardware of an electronic computer. In this article, we solved this problem by employing two kinds of DNA strings, one is called result and operation string while the other is named carrier. The result and operation string contains some carry information by its own and denotes the ultimate result while the carrier is just for carrying use. The significance of this algorithm is the original code, the fairly easy steps to follow and the feasibility under current molecular biological technology.

  12. Network Tomography Based on Additive Metrics

    CERN Document Server

    Ni, Jian

    2008-01-01

    Inference of the network structure (e.g., routing topology) and dynamics (e.g., link performance) is an essential component in many network design and management tasks. In this paper we propose a new, general framework for analyzing and designing routing topology and link performance inference algorithms using ideas and tools from phylogenetic inference in evolutionary biology. The framework is applicable to a variety of measurement techniques. Based on the framework we introduce and develop several polynomial-time distance-based inference algorithms with provable performance. We provide sufficient conditions for the correctness of the algorithms. We show that the algorithms are consistent (return correct topology and link performance with an increasing sample size) and robust (can tolerate a certain level of measurement errors). In addition, we establish certain optimality properties of the algorithms (i.e., they achieve the optimal $l_\\infty$-radius) and demonstrate their effectiveness via model simulation.

  13. High-Efficient Circuits for Ternary Addition

    Directory of Open Access Journals (Sweden)

    Reza Faghih Mirzaee

    2014-01-01

    Full Text Available New ternary adders, which are fundamental components of ternary addition, are presented in this paper. They are on the basis of a logic style which mostly generates binary signals. Therefore, static power dissipation reaches its minimum extent. Extensive different analyses are carried out to examine how efficient the new designs are. For instance, the ternary ripple adder constructed by the proposed ternary half and full adders consumes 2.33 μW less power than the one implemented by the previous adder cells. It is almost twice faster as well. Due to their unique superior characteristics for ternary circuitry, carbon nanotube field-effect transistors are used to form the novel circuits, which are entirely suitable for practical applications.

  14. Use of waste rubber as concrete additive.

    Science.gov (United States)

    Chou, Liang Hsing; Lu, Chun-Ku; Chang, Jen-Ray; Lee, Maw Tien

    2007-02-01

    For resource reutilization, scrap tyres have long been investigated as an additive to concrete to form 'Rubcrete' for various applications and have shown promising results. However, the addition of rubber particles leads to the degradation of physical properties, particularly, the compressive strength of the concrete. In this study, a theoretical model was proposed to shed light on the mechanisms of decrease in compressive strength due to the addition of rubber particles as well as improvement in compressive strength through modification of particle surfaces. The literature suggests that the compressive strength can be improved by soaking the rubber particles in alkaline solution first to increase the inter-phase bonding between the rubber particles and cement. Instead, we discovered that the loss in compressive strength was due to local imperfections in the hydration of cement, induced by the addition of heterogeneous and hydrophobic rubber particles. Microscopic studies showed that the rubber particles disturbed the water transfer to create channels, which were prone to cracking and led to a loss in the compressive strength. Unexpectedly, no cracking was found along the surfaces of the rubber particles, indicating that the bonding strength between the rubber particles and cement phases was not the critical factor in determining the compressive strength. Therefore, a theoretical model was proposed to describe the water transfer in the Rubcrete specimens to explain the experimental data. In the model, the local water available for hydration (Q) is: Q = -A(slv)/6piv, where Q, A(slv), and v are mass flow rate (kg s(-1)), Hamaker constant (J), and dynamic viscosity (m2 s(-1)), respectively. By maximizing the quantity Q and, in turn, the Hamaker constant A(slv), the compressive strength could be improved. The Hamaker constant A(slv) for water film on rubber particle surfaces was smaller than that for the hydrated cement particles; the water transfer rate was lower in

  15. Additive subgroups of topological vector spaces

    CERN Document Server

    Banaszczyk, Wojciech

    1991-01-01

    The Pontryagin-van Kampen duality theorem and the Bochner theorem on positive-definite functions are known to be true for certain abelian topological groups that are not locally compact. The book sets out to present in a systematic way the existing material. It is based on the original notion of a nuclear group, which includes LCA groups and nuclear locally convex spaces together with their additive subgroups, quotient groups and products. For (metrizable, complete) nuclear groups one obtains analogues of the Pontryagin duality theorem, of the Bochner theorem and of the Lévy-Steinitz theorem on rearrangement of series (an answer to an old question of S. Ulam). The book is written in the language of functional analysis. The methods used are taken mainly from geometry of numbers, geometry of Banach spaces and topological algebra. The reader is expected only to know the basics of functional analysis and abstract harmonic analysis.

  16. Intolerance to food additives - does it exist?

    Science.gov (United States)

    Turner, Paul J; Kemp, Andrew S

    2012-02-01

    'Food intolerance' is often confused with a range of adverse symptoms which may be coincidental to ingestion of food. 'Food intolerance' is defined as a reaction in which symptoms must be objectively reproducible and not known to involve an immunological mechanism. A more precise term is non-allergic food hypersensitivity, which contrasts with food allergies which are due to an immunological mechanism. Some children will experience food reactions to food additives. Reported symptoms range from urticaria/angioedema to hyperactive behaviours. While parents/carers report that over one fifth of children experience of food reaction, only 1 in 20 of these are confirmed to have a non-allergic food hypersensitivity on testing.

  17. Nonparametric additive regression for repeatedly measured data

    KAUST Repository

    Carroll, R. J.

    2009-05-20

    We develop an easily computed smooth backfitting algorithm for additive model fitting in repeated measures problems. Our methodology easily copes with various settings, such as when some covariates are the same over repeated response measurements. We allow for a working covariance matrix for the regression errors, showing that our method is most efficient when the correct covariance matrix is used. The component functions achieve the known asymptotic variance lower bound for the scalar argument case. Smooth backfitting also leads directly to design-independent biases in the local linear case. Simulations show our estimator has smaller variance than the usual kernel estimator. This is also illustrated by an example from nutritional epidemiology. © 2009 Biometrika Trust.

  18. Object attributes combine additively in visual search.

    Science.gov (United States)

    Pramod, R T; Arun, S P

    2016-01-01

    We perceive objects as containing a variety of attributes: local features, relations between features, internal details, and global properties. But we know little about how they combine. Here, we report a remarkably simple additive rule that governs how these diverse object attributes combine in vision. The perceived dissimilarity between two objects was accurately explained as a sum of (a) spatially tuned local contour-matching processes modulated by part decomposition; (b) differences in internal details, such as texture; (c) differences in emergent attributes, such as symmetry; and (d) differences in global properties, such as orientation or overall configuration of parts. Our results elucidate an enduring question in object vision by showing that the whole object is not a sum of its parts but a sum of its many attributes.

  19. Additively Manufactured and Surface Biofunctionalized Porous Nitinol.

    Science.gov (United States)

    Gorgin Karaji, Z; Speirs, M; Dadbakhsh, S; Kruth, J-P; Weinans, H; Zadpoor, A A; Amin Yavari, S

    2017-01-18

    Enhanced bone tissue regeneration and improved osseointegration are among the most important goals in design of multifunctional orthopedic biomaterials. In this study, we used additive manufacturing (selective laser melting) to develop multifunctional porous nitinol that combines superelasticity with a rationally designed microarchitecture and biofunctionalized surface. The rational design based on triply periodic minimal surfaces aimed to properly adjust the pore size, increase the surface area (thereby amplifying the effects of surface biofunctionalization), and resemble the curvature characteristics of trabecular bone. The surface of additively manufactured (AM) porous nitinol was biofunctionalized using polydopamine-immobilized rhBMP2 for better control of the release kinetics. The actual morphological properties of porous nitinol measured by microcomputed tomography (e.g., open/close porosity, and surface area) closely matched the design values. The superelasticity originated from the austenite phase formed in the nitinol porous structure at room temperature. Polydopamine and rhBMP2 signature peaks were confirmed by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy tests. The release of rhBMP2 continued until 28 days. The early time and long-term release profiles were found to be adjustable independent of each other. In vitro cell culture showed improved cell attachment, cell proliferation, cell morphology (spreading, spindle-like shape), and cell coverage as well as elevated levels of ALP activity and increased calcium content for biofunctionalized surfaces as compared to as-manufactured specimens. The demonstrated functionalities of porous nitinol could be used as a basis for deployable orthopedic implants with rationally designed microarchitectures that maximize bone tissue regeneration performance by release of biomolecules with adjustable and well-controlled release profiles.

  20. Feasibility and Testing of Additive Manufactured Components

    Energy Technology Data Exchange (ETDEWEB)

    Dehoff, Ryan R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hummelt, Ed [Eaton Corporation, Milwaukee, WI (United States); Solovyeva, Lyudmila [Eaton Corporation, Milwaukee, WI (United States)

    2016-09-01

    This project focused on demonstrating the ability to fabricate two parts with different geometry: an arc flash interrupter and a hydraulic manifold. Eaton Corporation provided ORNL solid models, information related to tolerances and sensitive parameters of the parts and provided testing and evaluation. ORNL successfully manufactured both components, provided cost models of the manufacturing (materials, labor, time and post processing) and delivered test components for Eaton evaluation. The arc flash suppressor was fabricated using the Renishaw laser powder bed technology in CoCrMo while the manifold was produced from Ti-6Al-4V using the Arcam electron beam melting technology. These manufacturing techniques were selected based on the design and geometrical tolerances required. A full-scale manifold was produced on the Arcam A2 system (nearly 12 inches tall). A portion of the manifold was also produced in the Arcam Q10 system. Although a full scale manifold could not be produced in the system, a full scale manifold is expected to have similar material properties, geometric accuracy, and surface finish as could be fabricated on an Arcam Q20 system that is capable of producing four full scale manifolds in a production environment. In addition to the manifold, mechanical test specimens, geometric tolerance artifacts, and microstructure samples were produced alongside the manifold. The development and demonstration of these two key components helped Eaton understand the impact additive manufacturing can have on many of their existing products. By working within the MDF and leveraging ORNL’s manufacturing and characterization capabilities, the work will ensure the rapid insertion and commercialization of this technology.

  1. Mechanical Properties of Additively Manufactured Thick Honeycombs

    Directory of Open Access Journals (Sweden)

    Reza Hedayati

    2016-07-01

    Full Text Available Honeycombs resemble the structure of a number of natural and biological materials such as cancellous bone, wood, and cork. Thick honeycomb could be also used for energy absorption applications. Moreover, studying the mechanical behavior of honeycombs under in-plane loading could help understanding the mechanical behavior of more complex 3D tessellated structures such as porous biomaterials. In this paper, we study the mechanical behavior of thick honeycombs made using additive manufacturing techniques that allow for fabrication of honeycombs with arbitrary and precisely controlled thickness. Thick honeycombs with different wall thicknesses were produced from polylactic acid (PLA using fused deposition modelling, i.e., an additive manufacturing technique. The samples were mechanically tested in-plane under compression to determine their mechanical properties. We also obtained exact analytical solutions for the stiffness matrix of thick hexagonal honeycombs using both Euler-Bernoulli and Timoshenko beam theories. The stiffness matrix was then used to derive analytical relationships that describe the elastic modulus, yield stress, and Poisson’s ratio of thick honeycombs. Finite element models were also built for computational analysis of the mechanical behavior of thick honeycombs under compression. The mechanical properties obtained using our analytical relationships were compared with experimental observations and computational results as well as with analytical solutions available in the literature. It was found that the analytical solutions presented here are in good agreement with experimental and computational results even for very thick honeycombs, whereas the analytical solutions available in the literature show a large deviation from experimental observation, computational results, and our analytical solutions.

  2. Additive Construction using Basalt Regolith Fines

    Science.gov (United States)

    Mueller, Robert P.; Sibille, Laurent; Hintze, Paul E.; Lippitt, Thomas C.; Mantovani, James G.; Nugent, Matthew W.; Townsend, Ivan I.

    2014-01-01

    Planetary surfaces are often covered in regolith (crushed rock), whose geologic origin is largely basalt. The lunar surface is made of small-particulate regolith and areas of boulders located in the vicinity of craters. Regolith composition also varies with location, reflecting the local bedrock geology and the nature and efficiency of the micrometeorite-impact processes. In the lowland mare areas (suitable for habitation), the regolith is composed of small granules (20 - 100 microns average size) of mare basalt and volcanic glass. Impacting micrometeorites may cause local melting, and the formation of larger glassy particles, and this regolith may contain 10-80% glass. Studies of lunar regolith are traditionally conducted with lunar regolith simulant (reconstructed soil with compositions patterned after the lunar samples returned by Apollo). The NASA Kennedy Space Center (KSC) Granular Mechanics & Regolith Operations (GMRO) lab has identified a low fidelity but economical geo-technical simulant designated as Black Point-1 (BP-1). It was found at the site of the Arizona Desert Research and Technology Studies (RATS) analog field test site at the Black Point lava flow in adjacent basalt quarry spoil mounds. This paper summarizes activities at KSC regarding the utilization of BP-1 basalt regolith and comparative work with lunar basalt simulant JSC-1A as a building material for robotic additive construction of large structures. In an effort to reduce the import or in-situ fabrication of binder additives, we focused this work on in-situ processing of regolith for construction in a single-step process after its excavation. High-temperature melting of regolith involves techniques used in glassmaking and casting (with melts of lower density and higher viscosity than those of metals), producing basaltic glass with high durability and low abrasive wear. Most Lunar simulants melt at temperatures above 1100 C, although melt processing of terrestrial regolith at 1500 C is not

  3. Behaviors of Polymer Additives Under EHL and Influences of Interactions Between Additives on Friction Modification

    Science.gov (United States)

    Sakurai, T.

    1984-01-01

    Polymer additives have become requisite for the formulation of multigrade engine oils. The behavior of polymethacrylate (PMA)-thickened oils as lubricants in concentrated contacts under nominal rolling and pure sliding conditions was investigated by conventional optical interferometry. The PMA thickened oils behaved differently from the base oil in the formation of elastohydrodynamic (EHL) films. The higher the elastohydrodynamic molecular weight of the PMA contained in the lubricant, the thinner was the oil film under EHL conditions. The film thickness of shear-degraded PMA-thickened oils was also investigated. The behavior of graphite particles dispersed in both the base oil and the PMA-thickened oil was studied under pure sliding by taking photomicrographs. Many kinds of additives are contained in lubricating oil and the interactions between additives are considered. The interactions of zinc-organodithiophosphates (ZDP) with other additives is discussed.

  4. Food Additives Permitted for Direct Addition to Food for Human Consumption; Folic Acid. Final rule.

    Science.gov (United States)

    2016-04-15

    The Food and Drug Administration (FDA or we) is amending the food additive regulations to provide for the safe use of folic acid in corn masa flour. We are taking this action in response to a food additive petition filed jointly by Gruma Corporation, Spina Bifida Association, March of Dimes Foundation, American Academy of Pediatrics, Royal DSM N.V., and National Council of La Raza.

  5. Additionality of global benefits and financial additionality in the context of the AIJ negotiations

    Energy Technology Data Exchange (ETDEWEB)

    Puhl, I.

    1996-12-31

    The Conference of the Party at their first meeting (COP1) took a decision regarding criteria for joint implementation as indicated in Art. 4.2 (a) of the FCCC which established a pilot phase for activities implemented jointly (AIJ) under the pilot phase. Besides some more technical issues this decision specified that such measures should bring about real, measurable and long-term environmental benefits related to the mitigation of climate change that would not have occurred in the absence of such activities. It also established that the financing of AIJ shall be additional to the financial obligations of developed country parties. These two requirements are called the additionality criteria for AIJ. The first refers to the realness of GHG emission abatement (which means reduction compared to a baseline) whereas the second describes that funds earmarked for AIJ have no other objective (i.e. profit making, export promotion) but to reduce GHG emissions to avoid the free-riding of investors and subsequently developed country parties. The reporting framework as well as the reporting requirements under national programs do not specify further the two types of additionality and even though research focuses on issues like baseline determination there has been no attempt so far to identify approaches which contribute towards defining strict and practicable methods and guidelines to frame additionality criteria. The first FCCC assessment of pilot project reporting revealed that in the reporting of activities, emissions additionality often remained unclear, especially in cases where AIJ was only a portion of an existing or already planned project, and that there is a point about how to account for financial additionality. It subsequently proposed to develop a uniform approach to baseline determination and the assessment of emission (reduction) additionality and financial additionality.

  6. IN718 Additive Manufacturing Properties and Influences

    Science.gov (United States)

    Lambert, Dennis M.

    2015-01-01

    The results of tensile, fracture, and fatigue testing of IN718 coupons produced using the selective laser melting (SLM) additive manufacturing technique are presented. The data have been "sanitized" to remove the numerical values, although certain references to material standards are provided. This document provides some knowledge of the effect of variation of controlled build parameters used in the SLM process, a snapshot of the capabilities of SLM in industry at present, and shares some of the lessons learned along the way. For the build parameter characterization, the parameters were varied over a range that was centered about the machine manufacturer's recommended value, and in each case they were varied individually, although some co-variance of those parameters would be expected. Tensile, fracture, and high-cycle fatigue properties equivalent to wrought IN718 are achievable with SLM-produced IN718. Build and post-build processes need to be determined and then controlled to established limits to accomplish this. It is recommended that a multi-variable evaluation, e.g., design-of experiment (DOE), of the build parameters be performed to better evaluate the co-variance of the parameters.

  7. Additive Manufacturing of Ultem Polymers and Composites

    Science.gov (United States)

    Chuang, Kathy C.; Grady, Joseph E.; Draper, Robert D.; Shin, Euy-Sik E.; Patterson, Clark; Santelle, Thomas D.

    2015-01-01

    The objective of this project was to conduct additive manufacturing to produce aircraft engine components by Fused Deposition Modeling (FDM), using commercially available polyetherimdes Ultem 9085 and experimental Ultem 1000 filled with 10 chopped carbon fiber. A property comparison between FDM-printed and injection molded coupons for Ultem 9085, Ultem 1000 resin and the fiber-filled composite Ultem 1000 was carried out. Furthermore, an acoustic liner was printed from Ultem 9085 simulating conventional honeycomb structured liners and tested in a wind tunnel. Composite compressor inlet guide vanes were also printed using fiber-filled Ultem 1000 filaments and tested in a cascade rig. The fiber-filled Ultem 1000 filaments and composite vanes were characterized by scanning electron microscope (SEM) and acid digestion to determine the porosity of FDM-printed articles which ranged from 25-31. Coupons of Ultem 9085, experimental Ultem 1000 composites and XH6050 resin were tested at room temperature and 400F to evaluate their corresponding mechanical properties.

  8. Additive Manufacturing: Making Imagination the Major Limitation

    Science.gov (United States)

    Zhai, Yuwei; Lados, Diana A.; LaGoy, Jane L.

    2014-05-01

    Additive manufacturing (AM) refers to an advanced technology used for the fabrication of three-dimensional near-net-shaped functional components directly from computer models, using unit materials. The fundamentals and working principle of AM offer several advantages, including near-net-shape capabilities, superior design and geometrical flexibility, innovative multi-material fabrication, reduced tooling and fixturing, shorter cycle time for design and manufacturing, instant local production at a global scale, and material, energy, and cost efficiency. Well suiting the requests of modern manufacturing climate, AM is viewed as the new industrial revolution, making its way into a continuously increasing number of industries, such as aerospace, defense, automotive, medical, architecture, art, jewelry, and food. This overview was created to relate the historical evolution of the AM technology to its state-of-the-art developments and emerging applications. Generic thoughts on the microstructural characteristics, properties, and performance of AM-fabricated materials will also be discussed, primarily related to metallic materials. This write-up will introduce the general reader to specifics of the AM field vis-à-vis advantages and common techniques, materials and properties, current applications, and future opportunities.

  9. Towards Mobile Microrobot Swarms for Additive Micromanufacturing

    Directory of Open Access Journals (Sweden)

    David Cappelleri

    2014-09-01

    Full Text Available In this paper, a novel approach to achieving the independent control of multiple magnetic microrobots is presented. The approach utilizes a specialized substrate consisting of a fine grid of planar, MEMS-fabricated micro coils of the same size as the microrobots (≤ 500 μm. The coils can be used to generate real magnetic potentials and, therefore, attractive and repulsive forces in the workspace to control the trajectories of the microrobots. Initial work on modelling the coil and microrobot behavior is reported along with simulation results for navigating one and two microrobots along independent desired trajectories. Qualitative results from a scaled-up printed circuit board version of the specialized substrate operating on permanent magnets are presented and offer proof-of-concept results for the approach. These tests also provide insights for practical implementations of such a system, which are similarly reported. The ultimate goal of this work is to use swarms of independently controlled microrobots in advanced, additive manufacturing applications.

  10. Additional EIPC Study Analysis. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Hadley, Stanton W [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gotham, Douglas J. [Purdue Univ., West Lafayette, IN (United States); Luciani, Ralph L. [Navigant Consultant Inc., Suwanee, GA (United States)

    2014-12-01

    Between 2010 and 2012 the Eastern Interconnection Planning Collaborative (EIPC) conducted a major long-term resource and transmission study of the Eastern Interconnection (EI). With guidance from a Stakeholder Steering Committee (SSC) that included representatives from the Eastern Interconnection States Planning Council (EISPC) among others, the project was conducted in two phases. Phase 1 involved a long-term capacity expansion analysis that involved creation of eight major futures plus 72 sensitivities. Three scenarios were selected for more extensive transmission- focused evaluation in Phase 2. Five power flow analyses, nine production cost model runs (including six sensitivities), and three capital cost estimations were developed during this second phase. The results from Phase 1 and 2 provided a wealth of data that could be examined further to address energy-related questions. A list of 14 topics was developed for further analysis. This paper brings together the earlier interim reports of the first 13 topics plus one additional topic into a single final report.

  11. Influence of and additives on acetylene detonation

    Science.gov (United States)

    Drakon, A.; Emelianov, A.; Eremin, A.

    2014-03-01

    The influence of and admixtures (known as detonation suppressors for combustible mixtures) on the development of acetylene detonation was experimentally investigated in a shock tube. The time-resolved images of detonation wave development and propagation were registered using a high-speed streak camera. Shock wave velocity and pressure profiles were measured by five calibrated piezoelectric gauges and the formation of condensed particles was detected by laser light extinction. The induction time of detonation development was determined as the moment of a pressure rise at the end plate of the shock tube. It was shown that additive had no influence on the induction time. For , a significant promoting effect was observed. A simplified kinetic model was suggested and characteristic rates of diacetylene formation were estimated as the limiting stage of acetylene polymerisation. An analysis of the obtained data indicated that the promoting species is atomic chlorine formed by pyrolysis, which interacts with acetylene and produces radical, initiating a chain mechanism of acetylene decomposition. The results of kinetic modelling agree well with the experimental data.

  12. Computed tomography characterisation of additive manufacturing materials.

    Science.gov (United States)

    Bibb, Richard; Thompson, Darren; Winder, John

    2011-06-01

    Additive manufacturing, covering processes frequently referred to as rapid prototyping and rapid manufacturing, provides new opportunities in the manufacture of highly complex and custom-fitting medical devices and products. Whilst many medical applications of AM have been explored and physical properties of the resulting parts have been studied, the characterisation of AM materials in computed tomography has not been explored. The aim of this study was to determine the CT number of commonly used AM materials. There are many potential applications of the information resulting from this study in the design and manufacture of wearable medical devices, implants, prostheses and medical imaging test phantoms. A selection of 19 AM material samples were CT scanned and the resultant images analysed to ascertain the materials' CT number and appearance in the images. It was found that some AM materials have CT numbers very similar to human tissues, FDM, SLA and SLS produce samples that appear uniform on CT images and that 3D printed materials show a variation in internal structure.

  13. Additive Layer Manufacturing for Launcher's Applications

    Science.gov (United States)

    Vilanova, J.; Romera, P.; Lasagni, F.; Zorrilla, A.; Perinan, A.

    2014-06-01

    In the next years the European space industry has the challenge of maintaining its competitiveness in launch vehicles (LV) production, due to the growth of competition worldwide. It has to assure its position developing new applied technologies. In this field the effort is focussed on the production of short series of customized products, like payloads, flight components or launcher parts. ALM (Additive Layer Manufacturing) could be a powerful tool that offers new competitiveness factors for this industry, comprising a set of emerging technologies that are becoming a competitor to forming, casting and machining as well as being utilised directly as a complementary alternative.Originally used for prototypes and models, now ALM becomes a very useful technology capable to fabricate functional parts for the space industrial sector. Its demands on rapid technologies are different to "earth" industries, and they aren't so easily satisfied because space is a field with different requirements depending on its application: launchers, reusable vehicles, satellites, probes, low gravity researches, manned spacecraft, or even moon and planetary exploration.This paper reports on the ALM potential applications, under ESA requirements, exploring the challenges and possibilities for its use in the launchers market, trying to answer two basic questions: the first one, whether ALM is a mature technology to be ready for its use as flight hardware; and the second one, if it can be used to reduce the product cycle, and consequently, the development, production and operational costs.

  14. Biobased additive plasticizing Polylactic acid (PLA

    Directory of Open Access Journals (Sweden)

    Mounira Maiza

    2015-12-01

    Full Text Available Polylactic acid (PLA is an attractive candidate for replacing petrochemical polymers because it is from renewable resources. In this study, a specific PLA 2002D was melt-mixed with two plasticizers: triethyl citrate (TEC and acetyl tributyl citrate (ATBC. The plasticized PLA with various concentrations were analyzed by differential scanning calorimetry (DSC, dynamic mechanical analysis (DMA, melt flow index (MFI, thermogravimetric analysis (TGA, X-ray diffraction (XRD, UV-Visible spectroscopy and plasticizer migration test. Differential scanning calorimetry demonstrated that the addition of TEC and ATBC resulted in a decrease in glass transition temperature (Tg, and the reduction was the largest with the plasticizer having the lowest molecular weight (TEC. Plasticizing effect was also shown by decrease in the dynamic storage modulus and viscosity of plasticized mixtures compared to the treated PLA. The TGA results indicated that ATBC and TEC promoted a decrease in thermal stability of the PLA. The X-ray diffraction showed that the PLA have not polymorphic crystalline transition. Analysis by UV-Visible spectroscopy showed that the two plasticizers: ATBC and TEC have no effect on the color change of the films. The weight loss plasticizer with heating time and at 100°C is lesser than at 135 °C. Migration of TEC and ATBC results in cracks and changed color of material. We have concluded that the higher molecular weight of citrate in the studied exhibited a greater plasticizing effect to the PLA.

  15. Structure Property Studies for Additively Manufactured Parts

    Energy Technology Data Exchange (ETDEWEB)

    Milenski, Helen M [Univ. of Mexico, Los Alamos, NM (United States); Schmalzer, Andrew Michael [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Kelly, Daniel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-08-17

    Since the invention of modern Additive Manufacturing (AM) processes engineers and designers have worked hard to capitalize on the unique building capabilities that AM allows. By being able to customize the interior fill of parts it is now possible to design components with a controlled density and customized internal structure. The creation of new polymers and polymer composites allow for even greater control over the mechanical properties of AM parts. One of the key reasons to explore AM, is to bring about a new paradigm in part design, where materials can be strategically optimized in a way that conventional subtractive methods cannot achieve. The two processes investigated in my research were the Fused Deposition Modeling (FDM) process and the Direct Ink Write (DIW) process. The objectives of the research were to determine the impact of in-fill density and morphology on the mechanical properties of FDM parts, and to determine if DIW printed samples could be produced where the filament diameter was varied while the overall density remained constant.

  16. Americium separation from nuclear fuel dissolution using higher oxidation states.

    Energy Technology Data Exchange (ETDEWEB)

    Bruce J. Mincher

    2009-09-01

    Much of the complexity in current AFCI proposals is driven by the need to separate the minor actinides from the lanthanides. Partitioning and recycling Am, but not Cm, would allow for significant simplification because Am has redox chemistry that may be exploited while Cm does not. Here, we have explored methods based on higher oxidation states of Am (AmV and AmVI) to partition Am from the lanthanides. In a separate but related approach we have also initiated an investigation of the utility of TRUEX Am extraction from thiocyanate solution. The stripping of loaded TRUEX by Am oxidation or SCN- has not yet proved successful; however, the partitioning of inextractable AmV by TRUEX shows promise.

  17. Further Studies of Plutonium and Americium at Thule, Greenland

    DEFF Research Database (Denmark)

    Aarkrog, Asker; Dahlgaard, Henning; Nilsson, Karen Kristina;

    1984-01-01

    further away from the impact point and at some locations the vertical distribution indicated a downward displacement of Pu in the sediment column since 1974. Seawater and seaplants showed no evidence of the presence of Pu from sources other than fallout; but Pu in benthos varied nearly proportionally......, but in benthos 241Am/239,240Pu were two times higher than in sediments. Seaplants showed the same value of Am/Pu as seawater. There was no indication of any biomagnification of Pu or Am through the marine food chains at Thule....

  18. Property Data for Simulated Americium/Curium Glasses

    Energy Technology Data Exchange (ETDEWEB)

    Riley, B.J.; Smith, D.E.; Peeler, D.K.; Reamer, I.A.; Vienna, J.D.; Schweiger, M.J.

    1999-10-20

    The authors studied the properties of mixed lanthanide-alumino-borosilicate glasses. Fifty-five glasses were designed to augment a previous, Phase I, study by systematically varying the composition of Ln{sub 2}O{sub 3} and the concentrations of Ln{sub 2}O{sub 3}, SiO{sub 2}, B{sub 2}O{sub 3}, Al{sub 2}O{sub 3}, and SrO in glass. These glasses were designed and fabricated at the Savannah River Technology Center and tested at the Pacific Northwest National Laboratory. The properties measured include the high-temperature viscosity ({eta}) as a function of temperature (T) and the liquidus temperature (T{sub L}) of Phase II test glasses.

  19. Plutonium and americium contamination in Rocky Flats soil, 1973

    Energy Technology Data Exchange (ETDEWEB)

    Krey, P.; Hardy, E.; Volchok, H.; Toonkel, L.; Knuth, R.; Coppes, M.; Tamura, T.

    1976-03-01

    The plutonium mass isotopic analysis and the Am-241 analysis of soil samples from Rocky Flats identify the contamination as Pu which was processed in 1958. The Am-241 activity in the soil will reach its maximum in 2033 and represent 18 percent of the Pu-239-240 activity. Nuclide ratios indicate that current operations at Rocky Flats contribute little to the airborne Pu concentrations which are due to resuspension of the contaminated soil. Root uptake of Pu or Am by vegetation is slight or shows no discrimination among the isotopes and nuclides studied. The relationship between Pu deposition contour and the area enclosed by that contour has been verified for contour values extending over 7 orders of magnitude. This gives confidence to our calculations of the quantities of Pu released on and off the Rocky Flats plant site. (auth)

  20. Biosorption of americium-241 by immobilized Rhizopus arrihizus

    Energy Technology Data Exchange (ETDEWEB)

    Liao Jiali E-mail: liaojiali@163.com; Yang Yuanyou; Luo Shunzhong; Liu Ning; Jin Jiannan; Zhang Taiming; Zhao Pengji

    2004-01-01

    Rhizopus arrihizus (R. arrihizus), a fungus, which in previous experiments had shown encouraging ability to remove {sup 241}Am from solutions, was immobilized by calcium alginate and other reagents. The various factors affecting {sup 241}Am biosorption by the immobilized R. arrihizus were investigated. The results showed that not only can immobilized R. arrihizus adsorb {sup 241}Am as efficiently as free R. arrihizus, but that also can be used repeatedly or continuously. The biosorption equilibrium was achieved within 2 h, and more than 94% of {sup 241}Am was removed from {sup 241}Am solutions of 1.08 MBq/l by immobilized R. arrihizu in the pH range 1-7. Temperature did not affect the adsorption on immobilized R. arrihizus in the range 15-45 deg. C. After repeated adsorption for 8 times, the immobilized R. arrihizus still adsorbed more than 97% of {sup 241}Am. At this time, the total adsorption of {sup 241}Am was more than 88.6 KBq/g, and had not yet reached saturation. Ninety-five percent of the adsorbed {sup 241}Am was desorbed by saturated EDTA solution and 98% by 2 mol/l HNO{sub 3}.

  1. Additive manufacturing technologies of porous metal implants

    Directory of Open Access Journals (Sweden)

    Yang Quanzhan

    2014-06-01

    Full Text Available Biomedical metal materials with good corrosion resistance and mechanical properties are widely used in orthopedic surgery and dental implant materials, but they can easily cause stress shielding due to the significant difference in elastic modulus between the implant and human bones. The elastic modulus of porous metals is lower than that of dense metals. Therefore, it is possible to adjust the pore parameters to make the elastic modulus of porous metals match or be comparable with that of the bone tissue. At the same time, the open porous metals with pores connected to each other could provide the structural condition for bone ingrowth, which is helpful in strengthening the biological combination of bone tissue with the implants. Therefore, the preparation technologies of porous metal implants and related research have been drawing more and more attention due to the excellent features of porous metals. Selective laser melting (SLM and electron beam melting technology (EBM are important research fields of additive manufacturing. They have the advantages of directly forming arbitrarily complex shaped metal parts which are suitable for the preparation of porous metal implants with complex shape and fine structure. As new manufacturing technologies, the applications of SLM and EBM for porous metal implants have just begun. This paper aims to understand the technology status of SLM and EBM, the research progress of porous metal implants preparation by using SLM and EBM, and the biological compatibility of the materials, individual design and manufacturing requirements. The existing problems and future research directions for porous metal implants prepared by SLM and EBM methods are discussed in the last paragraph.

  2. Additive manufacturing technologies of porous metal implants

    Institute of Scientific and Technical Information of China (English)

    Zhou Linxi; Yang Quanzhan; Zhang Guirong; Zhao Fangxin; Shen Gang; Yu Bo

    2014-01-01

    Biomedical metal materials with good corrosion resistance and mechanical properties are widely used in orthopedic surgery and dental implant materials, but they can easily cause stress shielding due to the signiifcant difference in elastic modulus between the implant and human bones. The elastic modulus of porous metals is lower than that of dense metals. Therefore, it is possible to adjust the pore parameters to make the elastic modulus of porous metals match or be comparable with that of the bone tissue. At the same time, the open porous metals with pores connected to each other could provide the structural condition for bone ingrowth, which is helpful in strengthening the biological combination of bone tissue with the implants. Therefore, the preparation technologies of porous metal implants and related research have been drawing more and more attention due to the excellent features of porous metals. Selective laser melting (SLM) and electron beam melting technology (EBM) are important research fields of additive manufacturing. They have the advantages of directly forming arbitrarily complex shaped metal parts which are suitable for the preparation of porous metal implants with complex shape and ifne structure. As new manufacturing technologies, the applications of SLM and EBM for porous metal implants have just begun. This paper aims to understand the technology status of SLM and EBM, the research progress of porous metal implants preparation by using SLM and EBM, and the biological compatibility of the materials, individual design and manufacturing requirements. The existing problems and future research directions for porous metal implants prepared by SLM and EBM methods are discussed in the last paragraph.

  3. CREATION OF THE MODEL ADDITIONAL PROTOCOL

    Energy Technology Data Exchange (ETDEWEB)

    Houck, F.; Rosenthal, M.; Wulf, N.

    2010-05-25

    In 1991, the international nuclear nonproliferation community was dismayed to discover that the implementation of safeguards by the International Atomic Energy Agency (IAEA) under its NPT INFCIRC/153 safeguards agreement with Iraq had failed to detect Iraq's nuclear weapon program. It was now clear that ensuring that states were fulfilling their obligations under the NPT would require not just detecting diversion but also the ability to detect undeclared materials and activities. To achieve this, the IAEA initiated what would turn out to be a five-year effort to reappraise the NPT safeguards system. The effort engaged the IAEA and its Member States and led to agreement in 1997 on a new safeguards agreement, the Model Protocol Additional to the Agreement(s) between States and the International Atomic Energy Agency for the Application of Safeguards. The Model Protocol makes explicit that one IAEA goal is to provide assurance of the absence of undeclared nuclear material and activities. The Model Protocol requires an expanded declaration that identifies a State's nuclear potential, empowers the IAEA to raise questions about the correctness and completeness of the State's declaration, and, if needed, allows IAEA access to locations. The information required and the locations available for access are much broader than those provided for under INFCIRC/153. The negotiation was completed in quite a short time because it started with a relatively complete draft of an agreement prepared by the IAEA Secretariat. This paper describes how the Model Protocol was constructed and reviews key decisions that were made both during the five-year period and in the actual negotiation.

  4. Fatigue crack growth in additive manufactured products

    Directory of Open Access Journals (Sweden)

    A. Riemer

    2015-10-01

    Full Text Available Additive Manufacturing (AM is a new innovative technique that allows the direct fabrication of complex, individual, delicate and high-strength products, based on their 3D data. Selective Laser Melting (SLM is one of the AM processes that generates metallic components layer by layer using powder-bed technique. The irradiation and consequent melting of metallic powder is realised by the laser source. Employing SLM, especially complex and individual products, such as implants or aerospace parts, are well suited for economic production in small batches. The first important issue in this work was to analyse the fatigue crack growth (FCG in titanium alloy Ti-6-4 and stainless steel 316L processed by SLM. As a first step, stress intensity range decreasing tests were performed on SLM samples in their “as-built” condition. The next step was to adopt measures for optimisation of fatigue crack growth performance of SLM parts. For this purpose various heat treatments such as stress relief annealing and hot isostatic pressing (HIP were applied to the CT specimens. Finally, the strong impact of heat treatment on the residual lifetime was demonstrated by numerical fatigue crack growth simulations. For this purpose, the hip joint implant consisting of Ti-6-4 and processed by SLM was taken into account. It was found that residual stresses have a strong influence on the crack growth in Ti-6-4, while the influence of the micro-pores on the threshold values remains low. In contrast the results for 316L show that its fracturemechanical behaviour is not affected by residual stresses, whereas the microstructural features lead to modification in the da/dN-K-data. The second fundamental aim of this work was to demonstrate the possibilities of the SLM process. For that reason, the individually tailored bicycle crank was optimised regarding its weight and local stresses and finally manufactured using the SLM system. The iterative optimisation procedure was based on

  5. A Public Opinion Survey on Correctional Education: Does Additional Information on Efficacy Lead to Additional Support?

    Science.gov (United States)

    Waterland, Keri Lynn

    2009-01-01

    Though much research has been done on the efficacy of correctional education on reducing recidivism rates for prison inmates, there is little research on the effect that information about the efficacy of correctional education has on public opinion. This study examined whether providing additional information regarding the efficacy of correctional…

  6. Comparison of Various Dynamic Balancing Principles Regarding Additional Mass and Additional Inertia

    NARCIS (Netherlands)

    Wijk, van der Volkert; Demeulenaere, Bram; Herder, Just L.

    2009-01-01

    The major disadvantage of existing dynamic balancing principles is that a considerable amount of mass and inertia is added to the system. The objectives of this article are to summarize, to compare, and to evaluate existing complete balancing principles regarding the addition of mass and the additio

  7. 37 CFR 1.776 - Calculation of patent term extension for a food additive or color additive.

    Science.gov (United States)

    2010-07-01

    ... extension for a food additive or color additive. 1.776 Section 1.776 Patents, Trademarks, and Copyrights... Calculation of patent term extension for a food additive or color additive. (a) If a determination is made pursuant to § 1.750 that a patent for a food additive or color additive is eligible for extension, the...

  8. 21 CFR 570.18 - Tolerances for related food additives.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Tolerances for related food additives. 570.18... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES General Provisions § 570.18 Tolerances for related food additives. (a) Food additives that cause similar or related pharmacological...

  9. 21 CFR 570.38 - Determination of food additive status.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Determination of food additive status. 570.38... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS FOOD ADDITIVES Food Additive Safety § 570.38 Determination of food additive status. (a) The Commissioner may, in accordance with § 570.35 (b)(4) or...

  10. A generalized additive regression model for survival times

    DEFF Research Database (Denmark)

    Scheike, Thomas H.

    2001-01-01

    Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models......Additive Aalen model; counting process; disability model; illness-death model; generalized additive models; multiple time-scales; non-parametric estimation; survival data; varying-coefficient models...

  11. 21 CFR 170.18 - Tolerances for related food additives.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tolerances for related food additives. 170.18... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES General Provisions § 170.18 Tolerances for related food additives. (a) Food additives that cause similar or related pharmacological effects will...

  12. 21 CFR 170.10 - Food additives in standardized foods.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Food additives in standardized foods. 170.10... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES General Provisions § 170.10 Food additives... the Act, which proposes the inclusion of a food additive in such definition and standard of...

  13. 21 CFR 170.38 - Determination of food additive status.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Determination of food additive status. 170.38... (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES Food Additive Safety § 170.38 Determination of food additive status. (a) The Commissioner may, in accordance with § 170.35(b)(4) or...

  14. 78 FR 28163 - Zentox Corporation; Withdrawal of Food Additive Petition

    Science.gov (United States)

    2013-05-14

    ... Additive Petition AGENCY: Food and Drug Administration, HHS. ACTION: Notice of withdrawal. SUMMARY: The... filing, of a food additive petition (FAP 8A4775) proposing that the food additive regulations be amended... Orange Ave., suite 710, Orlando, FL 32801, had filed a food additive petition (FAP 8A4775). The...

  15. Prevalence of phosphorus containing food additives in grocery stores

    Directory of Open Access Journals (Sweden)

    Janeen B. Leon

    2012-06-01

    In conclusion, phosphorus additives are commonly present in groceries and contribute significantly to the phosphorus content of foods. Moreover, phosphorus additive foods are less costly than additive-free foods. As a result, phosphorus additives may be an important contributor to hyperphosphatemia among persons with chronic kidney disease

  16. 76 FR 47210 - Notices of Filing of Petitions for Food Additives and Color Additives; Relocation in the Federal...

    Science.gov (United States)

    2011-08-04

    ... HUMAN SERVICES Food and Drug Administration Notices of Filing of Petitions for Food Additives and Color Additives; Relocation in the Federal Register AGENCY: Food and Drug Administration, HHS. ACTION: Notice... petitions for food additives and color additives that are published in accordance with the Federal...

  17. 78 FR 73434 - Food Additives Permitted for Direct Addition to Food for Human Consumption; Acacia (Gum Arabic)

    Science.gov (United States)

    2013-12-06

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 172 Food Additives Permitted for Direct Addition to Food for Human Consumption; Acacia (Gum Arabic) AGENCY: Food and Drug Administration, HHS. ACTION...--FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION 0 1. The authority...

  18. THE CATIONIC ADDITIVES USED IN COATED INK-JET PAPER

    Institute of Scientific and Technical Information of China (English)

    Dongmei Yu; Chuanshan Zhao; Kefu Chen

    2004-01-01

    This study investigated the effects of several different cationic additives on the viscosity 、zeta potential and printing properties of the ink-jet coating. The cationic additives have greatly improved sheet's gloss and printabilities.

  19. Cash Sub-additive Risk Measures and Interest Rate Ambiguity

    OpenAIRE

    El Karoui, Nicole; Ravanelli, Claudia

    2007-01-01

    A new class of risk measures called cash sub-additive risk measures is introduced to assess the risk of future financial, non financial and insurance positions. The debated cash additive axiom is relaxed into the cash sub-additive axiom to preserve the original difference between the numeraire of the current reserve amounts and future positions. Consequently, cash sub-additive risk measures can model stochastic and/or ambiguous interest rates or defaultable contingent claims. Practical exampl...

  20. 21 CFR 71.4 - Samples; additional information.

    Science.gov (United States)

    2010-04-01

    ... samples of the color additive, articles used as components thereof, or of the food, drug, or cosmetic in... additive, or articles used as components thereof, or of the food, drug, or cosmetic in which the color... respect to the safety of the color additive or the physical or technical effect it produces. The date...

  1. 48 CFR 1246.101-70 - Additional definitions.

    Science.gov (United States)

    2010-10-01

    ... or ceiling price for fixed price incentive contracts (see (FAR) 48 CFR 46.707), or at no increase in... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Additional definitions... CONTRACT MANAGEMENT QUALITY ASSURANCE General 1246.101-70 Additional definitions. At no additional cost...

  2. Process chain modeling and selection in an additive manufacturing context

    DEFF Research Database (Denmark)

    Thompson, Mary Kathryn; Stolfi, Alessandro; Mischkot, Michael

    2016-01-01

    This paper introduces a new two-dimensional approach to modeling manufacturing process chains. This approach is used to consider the role of additive manufacturing technologies in process chains for a part with micro scale features and no internal geometry. It is shown that additive manufacturing...... evolving fields like additive manufacturing....

  3. Navy Additive Manufacturing: Policy Analysis for Future DLA Material Support

    Science.gov (United States)

    2014-12-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA MBA PROFESSIONAL REPORT NAVY ADDITIVE MANUFACTURING : POLICY ANALYSIS FOR FUTURE...REPORT TYPE AND DATES COVERED MBA Professional Report 4. TITLE AND SUBTITLE NAVY ADDITIVE MANUFACTURING : POLICY ANALYSIS FOR FUTURE DLA MATERIAL...of technology adoption theories and their application to Additive Manufacturing (AM) in the Navy and wider Department of Defense. It examines AM

  4. 32 CFR 643.51 - Additional items concerning leasing.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Additional items concerning leasing. 643.51... PROPERTY REAL ESTATE Leases § 643.51 Additional items concerning leasing. In addition to the general and... leasing of Army real estate....

  5. Additional Raman Scattering Mechanism due to Transverse Polar Modes

    Institute of Scientific and Technical Information of China (English)

    CHENG Ze

    2001-01-01

    Longitudinal polar modes generate a macroscopic electric field in piezoelectric crystals and cause an additional mechanism of Raman scattering. The classical theory holds that transverse polar modes cannot produce such an additional mechanism. Our quantum theory shows that there is an additional Raman scattering mechanism arising from the electro-optic effect of transverse polar modes.``

  6. Entropies of the automata networks with additive rule

    Institute of Scientific and Technical Information of China (English)

    Guo-qingGU; GeCHEN; 等

    1996-01-01

    The matrix presentation for automata networks with additive rule are described.A set of entropy theorems of additive automata network are proved and an analytic formula of its entropy is built.For example,we proved that the topological entropy is identically equal to metric entropy for an additive antomata network.

  7. 40 CFR 51.117 - Additional provisions for lead.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Additional provisions for lead. 51.117... Additional provisions for lead. In addition to other requirements in §§ 51.100 through 51.116 the following requirements apply to lead. To the extent they conflict, there requirements are controlling over those of...

  8. An evaluation of estimation methods for determining addition in presbyopes

    Directory of Open Access Journals (Sweden)

    Leonardo Catunda Bittencourt

    2013-08-01

    Full Text Available PURPOSE: The optical correction of presbyopia must be handled individually. Our aim was to compare the methods used in addition to the refractive near vision, with the final addition used in presbyopic patients. METHODS: Eighty healthy subjects with a mean age of 49.7 years (range 40 to 60 years were studied. Tentative near additions were determined using four different techniques: one-half amplitude accommodation with minus lenses (AAL; one-third accommodative demand with positive lens (ADL; balanced range of accommodation with minus and positive lenses (BRA and crossed cylinder test with initial myopisation (CCT. The power of the addition was then refined to arrive at the final addition. RESULTS: The mean tentative near additions were lower than the final addition for ADL and BRA addition methods. The mean differences between tentative and final additions were low for all the tests examined (less than 0.25 D. The intervals between the 95% limits of agreement differed substantially and were always higher than ±0.50 D. CONCLUSION: All the methods used displayed similar behavior and provided a tentative addition close to the final addition. The coefficient of agreements (COA detected suggests that every tentative addition should be adjusted according to the particular needs of the patient.

  9. 21 CFR 173.310 - Boiler water additives.

    Science.gov (United States)

    2010-04-01

    ... CONSUMPTION Specific Usage Additives § 173.310 Boiler water additives. Boiler water additives may be safely... Applied Nutrition's Library, Food and Drug Administration, 5100 Paint Branch Pkwy., College Park, MD 20740... Center for Food Safety and Applied Nutrition's Library, Food and Drug Administration, 5100 Paint...

  10. 77 FR 13232 - Abbott Laboratories; Filing of Food Additive Petition

    Science.gov (United States)

    2012-03-06

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 172 Abbott Laboratories; Filing of Food Additive... Administration (FDA) is announcing that Abbott Laboratories has filed a petition proposing that the food additive...))), notice is given that a food additive petition (FAP 2A4788) has been filed by Abbott Laboratories,...

  11. 77 FR 53801 - Nexira; Filing of Food Additive Petition; Amendment

    Science.gov (United States)

    2012-09-04

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 172 Nexira; Filing of Food Additive Petition... Administration (FDA) is amending the filing notice for a food additive petition filed by Nexira proposing that the food additive regulations be amended to provide for the expanded safe use of acacia gum...

  12. 77 FR 5201 - Ecolab, Inc.; Filing of Food Additive Petition

    Science.gov (United States)

    2012-02-02

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 173 Ecolab, Inc.; Filing of Food Additive... Administration (FDA) is announcing that Ecolab, Inc., has filed a petition proposing that the food additive...) (21 U.S.C. 348(b)(5))), notice is given that a food additive petition (FAP 2A4785) has been filed...

  13. 76 FR 78866 - Nexira; Filing of Food Additive Petition

    Science.gov (United States)

    2011-12-20

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 172 Nexira; Filing of Food Additive Petition... Administration (FDA) is announcing that Nexira has filed a petition proposing that the food additive regulations... given that a food additive petition (FAP 1A4784) has been filed by Nexira, c/o Keller and Heckman...

  14. Addition formulae for Abelian functions associated with specialized curves.

    Science.gov (United States)

    Eilbeck, J C; Matsutani, S; Onishi, Y

    2011-03-28

    We discuss a family of multi-term addition formulae for Weierstrass functions on specialized curves of low genus with many automorphisms, concentrating mostly on the case of genus 1 and 2. In the genus 1 case, we give addition formulae for the equianharmonic and lemniscate cases, and in genus 2 we find some new addition formulae for a number of curves.

  15. Learning Basic Addition Facts from Choosing between Alternative Answers

    Science.gov (United States)

    van Galen, Mirte S.; Reitsma, Pieter

    2010-01-01

    The acquisition of addition facts was investigated in a practice study. Participants were 103 Grade 1 children who practiced simple addition problems with three different methods: (a) writing down the answer, (b) choosing between two alternative answers, and (c) filling in the second missing addend. On a test with simple addition problems,…

  16. 27 CFR 24.233 - Addition of spirits to wine.

    Science.gov (United States)

    2010-04-01

    ... wine. 24.233 Section 24.233 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Spirits § 24.233 Addition of spirits to wine. (a) Prior to the addition of spirits. Wine will be placed in tanks approved for the addition of spirits....

  17. 21 CFR 207.31 - Additional drug listing information.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Additional drug listing information. 207.31... Procedures for Domestic Drug Establishments § 207.31 Additional drug listing information. (a) In addition to... following information by letter or by Federal Register notice: (1) For a particular prescription drug...

  18. 21 CFR 70.45 - Allocation of color additives.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Allocation of color additives. 70.45 Section 70.45 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL COLOR ADDITIVES Safety Evaluation § 70.45 Allocation of color additives. Whenever, in the consideration of...

  19. 21 CFR 81.1 - Provisional lists of color additives.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Provisional lists of color additives. 81.1 Section... GENERAL SPECIFICATIONS AND GENERAL RESTRICTIONS FOR PROVISIONAL COLOR ADDITIVES FOR USE IN FOODS, DRUGS, AND COSMETICS § 81.1 Provisional lists of color additives. The Commissioner of Food and Drugs...

  20. The behaviour of molybdenum dialkyldithiocarbamate friction modifier additives

    CERN Document Server

    Graham, J C H

    2001-01-01

    In recent years there has been growing concern to produce energy-efficient lubricated components and modem engine oil specifications require lubricants to demonstrate fuel efficiency in standardised engine tests. One important method of producing low friction and thus fuel-efficient lubricants is to use oil-soluble, molybdenum-containing, friction modifier additives. In optimal conditions these additives are able to produce very low friction coefficients, in the range 0.045 to 0.075 in boundary lubrication conditions. Very little is known about the chemical and physical mechanisms by which oil soluble molybdenum additives form low friction films in tribological contacts. Information about their activity could lead to optimal use of these additives in lubricants and, therefore, more efficient engine running. The work outlined in this thesis investigated the behaviour of oil-soluble molybdenum additives and showed that these additives were able to effectively reduce friction in the absence of other additives su...

  1. 77 FR 52228 - Food Additives Permitted for Direct Addition to Food for Human Consumption; Vitamin D2

    Science.gov (United States)

    2012-08-29

    ... to Food for Human Consumption; Vitamin D2 Bakers Yeast AGENCY: Food and Drug Administration, HHS...--Food Additives Permitted for Direct Addition to Food for Human Consumption (21 CFR part 172), to... PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION 0 1. The authority citation for 21 CFR part...

  2. 27 CFR 19.318 - Addition of caramel to rum or brandy and addition of oak chips to spirits.

    Science.gov (United States)

    2010-04-01

    ... or brandy and addition of oak chips to spirits. 19.318 Section 19.318 Alcohol, Tobacco Products and... PLANTS Production § 19.318 Addition of caramel to rum or brandy and addition of oak chips to spirits... prior to production gauge. Oak chips which have not been treated with any chemical may be added...

  3. INFLUENCE OF NATURAL ADDITIVES ON PROTEIN COMPLEX OF BREAD

    Directory of Open Access Journals (Sweden)

    Dana Urminská

    2010-11-01

    Full Text Available The study focuses on researching the influence of natural additives on certain technological characteristics of mixtures used for bread production, more particularly the influence of N substances in used raw material on selected qualitative parameters of bread. The blends for bread production to be analysed were prepared by mixing wheat flour with an addition of oat, buckwheat, lentil and chickpea wholegrain flour in different portions (10, 20, 30, 40 and 50 %. The experiment showed that the addition of natural additives worsened the protein complex of the blends used in bread production (worsening also qualitative parameters known as product volume. The loaves prepared with an addition of buckwheat, oat, lentil and chickpea were evaluated to be of a lesser quality from a technological viewpoint when compared with pure wheat loaves. The lower content of gluten forming proteins and the generally changed protein composition of blends due to additives caused a lower percentage of wet gluten content, its lower extensibility and swelling capacity. The sedimentation value (Zeleny index decreased proportionally with the increase of addition until the level was unsatisfactory for raw material intended for bakery purposes. The N content in experimental loaves was higher than in the reference loaves and it increased according to the selected additive and its portion in the blend (more with the addition of lentil and chickpea, less in case of buckwheat and oat which is considered as positive from a nutritional point of view. But from the technological point of view the additives did not show any positive influence and caused a lower loaf bread volume. The most significant decrease of the loaf bread volume was found with the addition of 50 % of buckwheat (- 45.6 %. Better results were obtained with a lower portion of the additive: loaf with an addition of 30 % of chickpea (volume decreased by 12.8 % > loaf with an addition of 30 % of lentil (volume

  4. Versatility of cooperative transcriptional activation: a thermodynamical modeling analysis for greater-than-additive and less-than-additive effects.

    Directory of Open Access Journals (Sweden)

    Till D Frank

    Full Text Available We derive a statistical model of transcriptional activation using equilibrium thermodynamics of chemical reactions. We examine to what extent this statistical model predicts synergy effects of cooperative activation of gene expression. We determine parameter domains in which greater-than-additive and less-than-additive effects are predicted for cooperative regulation by two activators. We show that the statistical approach can be used to identify different causes of synergistic greater-than-additive effects: nonlinearities of the thermostatistical transcriptional machinery and three-body interactions between RNA polymerase and two activators. In particular, our model-based analysis suggests that at low transcription factor concentrations cooperative activation cannot yield synergistic greater-than-additive effects, i.e., DNA transcription can only exhibit less-than-additive effects. Accordingly, transcriptional activity turns from synergistic greater-than-additive responses at relatively high transcription factor concentrations into less-than-additive responses at relatively low concentrations. In addition, two types of re-entrant phenomena are predicted. First, our analysis predicts that under particular circumstances transcriptional activity will feature a sequence of less-than-additive, greater-than-additive, and eventually less-than-additive effects when for fixed activator concentrations the regulatory impact of activators on the binding of RNA polymerase to the promoter increases from weak, to moderate, to strong. Second, for appropriate promoter conditions when activator concentrations are increased then the aforementioned re-entrant sequence of less-than-additive, greater-than-additive, and less-than-additive effects is predicted as well. Finally, our model-based analysis suggests that even for weak activators that individually induce only negligible increases in promoter activity, promoter activity can exhibit greater-than-additive

  5. RAPID TEST METHOD FOR EVALUATION OF ANTIFREEZE ADDITIVE EFFICIENCY

    Directory of Open Access Journals (Sweden)

    S. V. Gushchin

    2015-01-01

    Full Text Available Usage of chemical additives while executing concrete works at negative temperatures is considered as a convenient and economical method. Range of the used antifreeze additives is rather wide. A great number of new additives are advertised but their characteristics have not been practically studied. Evaluation of the antifreeze additive efficiency is unfortunately rather long process and it does not provide comprehensive data on concrete structure formation processes. Due to this development of rapid and comprehensive methodology for construction companies is urgently required.Freezing processes of antifreeze additive aqueous solutions and hardening of cement paste with them have been investigated in the paper. The paper proposes a methodology for determination of freezing point for aqueous solutions of chemical additives of various applications. Identity of  freezing point for a chemical additive aqueous solution and cement paste with an equal concentration of the additive in the paste pore fluid has been determined while taking  calcium nitrate and sodium formate additives as an example. The paper demonstrates the possibility to evaluate efficiency of antifreeze additive action on the basis of kinetics in temperature changes of the cement paste with additives by its consecutive freezing and defrosting.  A methodology for operational evaluation in the field of chemical additive application for concreting items at negative temperatures has been offered in the paper.  The methodology does not require  deficient and expensive test-equipment. It can be applied at ordinary construction companies and it is comprehensible for personnel of low-qualification.  The paper shows the possibility to develop an original methodology for designing concrete structure which is based on operating efficiency determinations  for single and integrated antifreeze additives.

  6. Enhancement of Corrosion Resistance of Zinc Coatings Using Green Additives

    Science.gov (United States)

    Punith Kumar, M. K.; Srivastava, Chandan

    2014-10-01

    In the present work, morphology, microstructure, and electrochemical behavior of Zn coatings containing non-toxic additives have been investigated. Zn coatings were electrodeposited over mild steel substrates using Zn sulphate baths containing four different organic additives: sodium gluconate, dextrose, dextrin, and saccharin. All these additives are "green" and can be derived from food contents. Morphological and structural characterization using electron microscopy, x-ray diffraction, and texture co-efficient analysis revealed an appreciable alteration in the morphology and texture of the deposit depending on the type of additive used in the Zn plating bath. All the Zn coatings, however, were nano-crystalline irrespective of the type of additive used. Polarization and electrochemical impedance spectroscopic analysis, used to investigate the effect of the change in microstructure and morphology on corrosion resistance behavior, illustrated an improved corrosion resistance for Zn deposits obtained from plating bath containing additives as compared to the pure Zn coatings.

  7. Adverse reactions to food additives in children with atopic symptoms

    DEFF Research Database (Denmark)

    Fuglsang, G; Madsen, G; Halken, S

    1994-01-01

    In a multicenter study conducted at four Danish hospital pediatric departments, the parents of 472 consecutive children were informed of this project to determine the incidence of intolerance of food additives among children referred to an allergy clinic with symptoms of asthma, atopic dermatitis......, rhinitis, or urticaria. After a 2-week period on an additive-free diet, the children were challenged with the eliminated additives. The food additives investigated were coloring agents, preservatives, citric acid, and flavoring agents. Carbonated "lemonade" containing the dissolved additives was used...... dermatitis, asthma, urticaria, gastrointestinal symptoms), and citric acid (atopic dermatitis, gastrointestinal symptoms). The incidence of intolerance of food additives was 2% (6/335), as based on the double-blind challenge, and 7% (23/335), as based on the open challenge with lemonade. Children with atopic...

  8. Adverse reactions to food additives in children with atopic symptoms

    DEFF Research Database (Denmark)

    Fuglsang, G.; Madsen, Charlotte Bernhard; Halken, S.

    1994-01-01

    In a multicenter study conducted at four Danish hospital pediatric departments, the parents of 472 consecutive children were informed of this project to determine the incidence of intolerance of food additives among children referred to an allergy clinic with symptoms of asthma, atopic dermatitis......, rhinitis, or urticaria. After a 2-week period on an additive-free diet, the children were challenged with the eliminated additives. The food additives investigated were coloring agents, preservatives, citric acid, and flavoring agents. Carbonated ''lemonade'' containing the dissolved additives was used...... dermatitis, asthma, urticaria, gastrointestinal symptoms), and citric acid (atopic dermatitis, gastrointestinal symptoms). The incidence of intolerance of food additives was 2% (6/335), as based on the double-blind challenge, and 7% (23/335), as based on the open challenge with lemonade. Children with atopic...

  9. Cost-Efficient Low-Volume Production Through Additive Manufacturing

    OpenAIRE

    Solberg, Steffen

    2016-01-01

    Additive manufacturing, commonly known as 3D Printing, is a production method of rising popularity. The method works by adding layers of material, in contrast to subtracting, which is the dominating method today. The objective of this thesis has been to evaluate the cost-efficiency of producing relatively complex parts through additive manufacturing, compared to subtractive methods with production volumes less than 20 units. Initial findings narrow the additive methods down ...

  10. Machining of Additively Manufactured Parts: Implications for Surface Integrity

    OpenAIRE

    Oyelola, O.; Crawforth, P.; M'Saoubi, R.; Clare, A.T.

    2016-01-01

    Additive manufacturing methods continue to move towards production ready technologies with the widely extolled virtues of rapid transition from design to part and enhanced design freedoms. However, due to fundamental limitations of laser based processes for metal additive manufacturing, there is a significant ongoing need for these parts to be subject to additional machining operations. This paper reports on a study to investigate the machining behavior and surface integrity of Ti-6Al-4 V com...

  11. Effectiveness of Low Temperature Additives for Biodiesel Blends

    Science.gov (United States)

    2012-06-30

    UNCLASSIFIED EFFECTIVENESS OF LOW TEMPERATURE ADDITIVES FOR BIODIESEL BLENDS INTERIM REPORT TFLRF No. 428 by Steven R...Do not return it to the originator. UNCLASSIFIED UNCLASSIFIED EFFECTIVENESS OF LOW TEMPERATURE ADDITIVES FOR BIODIESEL BLENDS...17-2010 – 06-30-2012 4. TITLE AND SUBTITLE Effectiveness of Low Temperature Additives for Biodiesel Blends 5a. CONTRACT NUMBER W56HZV-09-C-0100

  12. Stereochemistry of enzymatic water addition to C=C bonds.

    Science.gov (United States)

    Chen, Bi-Shuang; Otten, Linda G; Hanefeld, Ulf

    2015-01-01

    Water addition to carbon-carbon double bonds using hydratases is attracting great interest in biochemistry. Most of the known hydratases are involved in primary metabolism and to a lesser extent in secondary metabolism. New hydratases have recently been added to the toolbox, both from natural sources or artificial metalloenzymes. In order to comprehensively understand how the hydratases are able to catalyse the water addition to carbon-carbon double bonds, this review will highlight the mechanistic and stereochemical studies of the enzymatic water addition to carbon-carbon double bonds, focusing on the syn/anti-addition and stereochemistry of the reaction.

  13. 10 CFR 1.3 - Sources of additional information.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Sources of additional information. 1.3 Section 1.3 Energy NUCLEAR REGULATORY COMMISSION STATEMENT OF ORGANIZATION AND GENERAL INFORMATION Introduction § 1.3 Sources of additional information. (a) A statement of the NRC's organization, policies,...

  14. 26 CFR 1.1250-2 - Additional depreciation defined.

    Science.gov (United States)

    2010-04-01

    ... 26 Internal Revenue 11 2010-04-01 2010-04-01 true Additional depreciation defined. 1.1250-2... Additional depreciation defined. (a) In general—(1) Definition for purposes of section 1250(b)(1). Except as... depreciation means: (i) In the case of property which at the time of disposition has a holding period...

  15. Characterization of the Tribological Behavior of Graphene-Based Additives

    Energy Technology Data Exchange (ETDEWEB)

    Erck, Robert [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-09-01

    XG-supplied nanocrystalline additives were extensively tested for friction and wear behavior. A technique for investigating the stability of additives was developed, and a report covered filtration and centrifugation methods for settling and filterable content. Friction and wear trends in partially and fully formulated oils were reported. Particle size analysis was performed and reported.

  16. 78 FR 6272 - Rules Relating to Additional Medicare Tax; Correction

    Science.gov (United States)

    2013-01-30

    ..., December 5, 2012 (77 FR 72268). The proposed regulations are relating to Additional Hospital Insurance Tax... proposed rulemaking and notice of public hearing (REG-130074-11), that was the subject of FR Doc. 2012... Internal Revenue Service 26 CFR Part 1 RIN 1545-BK54 Rules Relating to Additional Medicare Tax;...

  17. The Algebraic versus the Topological Approach to Additive Representations

    NARCIS (Netherlands)

    Wakker, P.P.

    1988-01-01

    It is proved that, under a nontriviality assumption, an additive function on a Cartesian product of connected topological spaces is continuous, whenever the preference relation, represented by this function, is continuous. The result is used to generalize a theorem of Debreu (1960) on additive repre

  18. 24 CFR 242.63 - Additional indebtedness and leasing.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Additional indebtedness and leasing. 242.63 Section 242.63 Housing and Urban Development Regulations Relating to Housing and Urban... Requirements § 242.63 Additional indebtedness and leasing. The mortgagor shall not enter into any...

  19. METHOD OF OBTAINING AN ADDITIVE FOR LUBRICATING OILS,

    Science.gov (United States)

    The method of obtaining an additive to lubricating oils , consisting of treating boron trifluoride with alkylphenol and alkylamine, is known. In this...case, (aminotrifluoralkyl)phenoxyborate is obtained which may be used as an antiwear additive for lubricating oils . The proposed method differs from

  20. 14 CFR 399.33 - Additional fare flexibility.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Additional fare flexibility. 399.33 Section 399.33 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) POLICY STATEMENTS STATEMENTS OF GENERAL POLICY Policies Relating to Rates and Tariffs § 399.33 Additional fare flexibility. For...

  1. Automated addition of Chelex solution to tubes containing trace items

    DEFF Research Database (Denmark)

    Stangegaard, Michael; Hansen, Thomas Møller; Hansen, Anders Johannes;

    2011-01-01

    Extraction of DNA from trace items for forensic genetic DNA typing using a manual Chelex based extraction protocol requires addition of Chelex solution to sample tubes containing trace items. Automated of addition of Chelex solution may be hampered by high viscosity of the solution and fast...

  2. Transport for a System with Additive Temporal-Spatial Noise

    Institute of Scientific and Technical Information of China (English)

    LI Jing-Hui; HAN Yin-Xia; CHEN Shi-Gang

    2004-01-01

    In this paper, we study the transport of the system with the additive temporal-spatial noise, by two models, i.e., a spatial asymmetry model and a spatial symmetry model. The study shows that the correlation of the additive noise with the space and the spatial asymmetry are ingredients for the transport.

  3. 24 CFR 3285.907 - Manufacturer additions to installation instructions.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Manufacturer additions to... Optional Information for Manufacturer's Installation Instructions § 3285.907 Manufacturer additions to installation instructions. A manufacturer may include in its installation instructions items that are...

  4. Inhibition behavior of some new mixed additives upon copper electrowinning

    Institute of Scientific and Technical Information of China (English)

    YU Run-lan; LIU Qing-ming; QIU Guan-zhou; FANG Zheng; TAN Jian-xi; YANG Peng

    2008-01-01

    As thiourea and sulfur-containing mixed additives contaminate cathodic copper, inhibition behavior of some new mixed additives such as gelatin+hexadecylpyridinium bromide (HDPBr), gelatin+polyethylene glycol(PEG), gelatin+polyacryl amide (PAM), gelatin+PEG+cetyl-tri-methyl ammonium bromide (CTABr) and gelatin+PAM+CTABr was investigated by cyclic voltammetry as well as cathodic polarization in order to improve the quality of cathodic copper in bio-metallurgical process. The results indicate that the inhibition performances of these additives are dependent on complex and adsorption behaviors as well as the deposit potential. For a solution of acidic copper sulpate containing 40 g/L Cu2+ and 180 g/L H2SO4, the additive (gelatin+HDPBr) is the most efficient among the investigated additives because HDPBr with a large organic cation and π electron can adsorb on the cathodic surface to block the active sites and Br- ion can precipitate Cu,'2+. To form Cu2Br2. The additive (gelatin+PAM) also has a better inhibition performance, while the additives (gelatin+PEG), (gelatin+PEG+CTABr) and (gelatin+PAM+CTABr) are comparatively lower inhibition performance compared with the additive (gelatin+thiourea) which has been frequently used so far.

  5. Automated addition of Chelex solution to tubes containing trace items

    DEFF Research Database (Denmark)

    Stangegaard, Michael; Hansen, Thomas Møller; Hansen, Anders Johannes;

    2011-01-01

    Extraction of DNA from trace items for forensic genetic DNA typing using a manual Chelex based extraction protocol requires addition of Chelex solution to sample tubes containing trace items. Automated of addition of Chelex solution may be hampered by high viscosity of the solution and fast sedim...

  6. Anomaly Detection In Additively Manufactured Parts Using Laser Doppler Vibrometery

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, Carlos A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2015-09-29

    Additively manufactured parts are susceptible to non-uniform structure caused by the unique manufacturing process. This can lead to structural weakness or catastrophic failure. Using laser Doppler vibrometry and frequency response analysis, non-contact detection of anomalies in additively manufactured parts may be possible. Preliminary tests show promise for small scale detection, but more future work is necessary.

  7. 14 CFR 135.421 - Additional maintenance requirements.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Additional maintenance requirements. 135.421 Section 135.421 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Maintenance, Preventive Maintenance, and Alterations § 135.421 Additional maintenance requirements. (a)...

  8. Influence of additive from sugar beet on white bread quality

    Directory of Open Access Journals (Sweden)

    Filipović Nada K.

    2004-01-01

    Full Text Available The additive of acceptable sensory, physical and chemical and microbiological characteristics was made from cossettes. Great water binding capacity related to microcrystals of cellulose qualifies this additive as a desired one in bread making process. Bread was baked in the laboratory and patent flour was used. The additive with particles smaller than 95 (m was supplemented in the quantities of 2, 5 and 10%. The data related to the influence of the quantity of additive on white bread quality point that parallel to increasing the amount of the additive in the dough, yield of dough and bread were also increased. Negative effects are detected as volume depression and inferior bread crumb quality and altered crumb color. The decrease in bread quality is small if 2% of additive was applied, but significant with 5 and 10%. The bread freshness was highly graded 48 hours after baking due to the ability of the additive to retain water. On the whole, bread of superior quality supplemented by 5 and 10% of the additive from sugar beet fiber can be easily made by fortifying flour with gluten and by adding appropriate dough conditioner.

  9. 78 FR 14664 - Food and Color Additives; Technical Amendments

    Science.gov (United States)

    2013-03-07

    ... and Color Additives; Technical Amendments AGENCY: Food and Drug Administration, HHS. ACTION: Final... regulations regarding food and color additives to correct minor errors (such as misspelled chemical names) and... archaic or obsolete office names and replace them with the current Office name ``Office of Food...

  10. Chemistry of Food Additives: Direct and Indirect Effects.

    Science.gov (United States)

    Pauli, George H.

    1984-01-01

    The primary component(s), impurities, and degradation products of polysorbate 80, nitrate and nitrite salts, and diethylpyrocarbonate (DEPC) are discussed. Safety considerations related to these food additives are also noted. The chick-edema factor which results from an additive in poultry feed is also discussed. (JN)

  11. 47 CFR 32.4520 - Additional paid-in capital.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Additional paid-in capital. 32.4520 Section 32... Additional paid-in capital. (a) This account shall include the difference between the net proceeds (including discount, premium and stock issuance expense) received from the issuance of capital stock and the...

  12. 46 CFR 308.104 - Additional war risk insurance.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Additional war risk insurance. 308.104 Section 308.104 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE War Risk Hull and Disbursements Insurance § 308.104 Additional war risk insurance. Owners or charterers...

  13. 46 CFR 401.425 - Provision for additional pilot.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Provision for additional pilot. 401.425 Section 401.425... REGULATIONS Rates, Charges, and Conditions for Pilotage Services § 401.425 Provision for additional pilot. The... Authority, Ltd., Canada, may require the assignment of two pilots to a ship upon request of the ship or...

  14. 33 CFR 101.310 - Additional communication devices.

    Science.gov (United States)

    2010-07-01

    ... plan under part 104 of this subchapter. See 33 CFR part 164 for additional information on AIS device... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Additional communication devices... communication devices. (a) Alert Systems. Alert systems, such as the ship security alert system required...

  15. Ultrashort mode-locked lasers with additional Raman active elements

    Science.gov (United States)

    Trunov, V. I.; Kirpichnikov, A. V.; Pestryakov, Efim V.; Petrov, V. V.; Komarov, A. K.; Komarov, Konstantin P.

    2002-05-01

    Numerical simulation of ultrashort pulse generation in the laser with a composite active medium and additional Raman active element in a cavity has been done. It was created that for some laser parameters the optimization of a Raman gain and a frequency shift values was resulted in additional shortening of pulse duration.

  16. Attitude Towards Physics and Additional Mathematics Achievement Towards Physics Achievement

    Science.gov (United States)

    Veloo, Arsaythamby; Nor, Rahimah; Khalid, Rozalina

    2015-01-01

    The purpose of this research is to identify the difference in students' attitude towards Physics and Additional Mathematics achievement based on gender and relationship between attitudinal variables towards Physics and Additional Mathematics achievement with achievement in Physics. This research focused on six variables, which is attitude towards…

  17. 23 CFR 658.11 - Additions, deletions, exceptions, and restrictions.

    Science.gov (United States)

    2010-04-01

    ... Division Office. Proposals for addition of routes to the National Network shall be accompanied by an analysis of suitability based on the criteria in § 658.9. (2) Proposals for additions that meet the... will be published in the Federal Register for public comment as a notice of proposed rulemaking...

  18. 5 CFR 179.218 - Additional administrative collection action.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Additional administrative collection action. 179.218 Section 179.218 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS CLAIMS COLLECTION STANDARDS Salary Offset § 179.218 Additional administrative collection...

  19. 5 CFR 179.309 - Additional administrative procedures.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Additional administrative procedures. 179.309 Section 179.309 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS CLAIMS COLLECTION STANDARDS Administrative Offset § 179.309 Additional administrative procedures....

  20. A review of selected chemical additives in cosmetic products.

    Science.gov (United States)

    Juhász, Margit Lai Wun; Marmur, Ellen S

    2014-01-01

    The addition of chemical additives to consumer cosmetic products is a common practice to increase cosmetic effectiveness, maintain cosmetic efficacy, and produce a longer-lasting, more viable product. Recently, manufacturers have come under attack for the addition of chemicals including dioxane, formaldehyde, lead/lead acetate, parabens, and phthalate, as these additives may prove harmful to consumer health. Although reports show that these products may indeed adversely affect human health, these studies are conducted using levels of the aforementioned chemicals at much higher levels of exposure than those found in cosmetic products. When cosmeceuticals are used as per manufacturer's instructions, it is estimated that the levels of harmful additives found in these products are considerably lower than reported toxic concentrations.

  1. Influence of Additives on Cigarette Related Health Risks

    Directory of Open Access Journals (Sweden)

    Klus H

    2014-12-01

    Full Text Available Tobacco additives play an important role in the manufacturing and for the quality of tobacco products, particularly cigarettes and roll-your-own tobaccos. Attention is increasingly given to the potential effects of additives on consumer behavior and health. This review is intended to compile, collate and - to some degree - evaluate the wealth of pertinent scientific information available from the published literature and other special sources. At first, the reasons are set forth for the use of additives in cigarette manufacturing. In response to the growing controversy over the attractiveness and addictiveness of smoking, the clarification of terms and concepts is followed by a detailed discussion of two kinds of substances with particular relevance: Additives like ammonium compounds that are claimed to increase nicotine availability, and additives that are claimed to increase nicotine addictiveness.

  2. ADDITIVE-INDUCED ENHANCEMENT OF OPTICAL CLARITY OF POLYACRYLAMIDE HYDROGEL

    Institute of Scientific and Technical Information of China (English)

    Jeffery Franklin; Zhi Yuan Wang

    2003-01-01

    The aqueous polymerization of acrylamide and crosslinking with N,N-methylenebisacrylamide afforded hydrogels displaying high levels of light scattering (poor optical clarity). Enhancement of the optical clarity within a polyacrylamide (PAm) hydrogel was accomplished through the implementation of"refractive index matching", Water-soluble additives were utilised to better match the refractive index inhomogeneities throughout a given hydrogel. This resulted in lower light scattering within the system and hence improved clarity. Amino acids, sugars, polymers, and other water-soluble additives such as glycerol were investigated by this methodology. Most additives investigated displayed potential for effectively reducing the light scattering within a PAm hydrogel as a function of increased additive concentration. On increasing the refractive index of the water medium, the overall refractive index of a PAm hydrogel was also observed to increase. This provided a quantitative means of determining the effectiveness of a given additive for improving the optical clarity within a hydrogel.

  3. Effects of some polymeric additives on the cocrystallization of caffeine

    Science.gov (United States)

    Chung, Jihae; Kim, Il Won

    2011-11-01

    Effects of polymeric additives on the model cocrystallization were examined. The model cocrystal was made from caffeine and oxalic acid, and poly(ethylene glycol) (PEG), poly( L-lactide) (PLLA), poly(ɛ-caprolactone) (PCL), and poly(acrylic acid) (PAA) were the additives. The cocrystals were formed as millimeter-sized crystals without additives, and they became microcrystals with PLLA and PCL, and nanocrystals with PAA. XRD and IR revealed that the cocrystal structure was unchanged despite the strong effects of the additives on the crystal morphology, although some decrease in crystallinity was observed with PAA as confirmed by DSC. The DSC study also showed that the cocrystal melted and recrystallized to form α-caffeine upon heating. The present study verified that the polymeric additives can be utilized to modulate the size and morphology of the cocrystals without interfering the intermolecular interactions essential to the integrity of the cocrystal structures.

  4. Hybrid Additive Manufacturing Technologies - An Analysis Regarding Potentials and Applications

    Science.gov (United States)

    Merklein, Marion; Junker, Daniel; Schaub, Adam; Neubauer, Franziska

    Imposing the trend of mass customization of lightweight construction in industry, conventional manufacturing processes like forming technology and chipping production are pushed to their limits for economical manufacturing. More flexible processes are needed which were developed by the additive manufacturing technology. This toolless production principle offers a high geometrical freedom and an optimized utilization of the used material. Thus load adjusted lightweight components can be produced in small lot sizes in an economical way. To compensate disadvantages like inadequate accuracy and surface roughness hybrid machines combining additive and subtractive manufacturing are developed. Within this paper the principles of mainly used additive manufacturing processes of metals and their possibility to be integrated into a hybrid production machine are summarized. It is pointed out that in particular the integration of deposition processes into a CNC milling center supposes high potential for manufacturing larger parts with high accuracy. Furthermore the combination of additive and subtractive manufacturing allows the production of ready to use products within one single machine. Additionally actual research for the integration of additive manufacturing processes into the production chain will be analyzed. For the long manufacturing time of additive production processes the combination with conventional manufacturing processes like sheet or bulk metal forming seems an effective solution. Especially large volumes can be produced by conventional processes. In an additional production step active elements can be applied by additive manufacturing. This principle is also investigated for tool production to reduce chipping of the high strength material used for forming tools. The aim is the addition of active elements onto a geometrical simple basis by using Laser Metal Deposition. That process allows the utilization of several powder materials during one process what

  5. Characterization of Starch Edible Films with Different Essential Oils Addition

    Directory of Open Access Journals (Sweden)

    Šuput Danijela

    2016-12-01

    Full Text Available This study investigated properties of starch-based edible films with oregano and black cumin essential oil addition. Essential oils addition positively affected film swelling (decreased due to essential oil addition, mechanical properties (tensile strength decreased while elongation at break increased, and water vapor barrier properties (decreased along with essential oils addition. Control film did not have any biological activity, which proves the need for essential oils addition in order to obtain active packaging. Oregano oil was more effective in terms of biological activity. Endothermal peak, above 200°C, represents total thermal degradation of edible films. Diffraction pattern of control film showed significant destruction of A-type crystal structure. Addition of essential oils resulted in peak shape change: diffraction peaks became narrower. Principal Component Analysis has been used to assess the effect of essential oils addition on final starch-based edible films characteristics with the aim to reveal directions for the film characteristics improvement, since the next phase will be optimal film application for food packaging.

  6. Influence of flux additives on iron ore oxidized pellets

    Institute of Scientific and Technical Information of China (English)

    FAN Xiao-hui; GAN Min; JIANG Tao; YUAN Li-shun; CHEN Xu-ling

    2010-01-01

    Six additives,i.e.,limestone,lime,magnesite,magnesia,dolomite and light-burned-dolomite,were added for investigating their influences on the pellet quality.For green balls,adding lime and light-burned-dolomite makes the wet drop strength decrease firstly,and then increase with further increase of additive dosage.Ca(OH)2 affects the bentonite properties at the beginning,but the binding property of Ca(OH)2 will be main when the dosage is higher.The other four additives decrease the drop strength for their disadvantageous physical properties.For preheated pellets,no mater what kind of additive is added,the compressive strength will be decreased because of unmineralized additives.For roasted pellets,calcium additives can form binding phase of calcium-ferrite,and suitable liquid phase will improve recrystallization of hematite,but excessive liquid will destroy the structure of pellets,so the compressive strength of pellet increases firstly and then drops.When adding magnesium additives,the strength will be decreased because of the oxidation of magnetite retarded by MgO.

  7. Production of fresh probiotic cheese with addition of transglutaminase

    Directory of Open Access Journals (Sweden)

    Vinka Radošević

    2007-04-01

    Full Text Available The aim of this research was to examine the influence of probiotic culture Lactobacillus acidophilus and enzyme transglutaminase (TG on quality and sensory properties of autochthonous fresh cheese from Zagreb region. Fresh, unpasteurized, skimmed milk was inoculated with TG at different temperatures and activation time (8 h at 11 ºC and 4 h at 25 ºC. Inactivation of the enzyme was carried out during the process of pasteurization (65ºC/30 min. The milk for fresh cheese production was further inoculated with mesophilic culture of lactic acid bacteria MM101 and probiotic strain Lactobacillus acidophilus LAC-1. Besides the trial samples with addition of TG and probiotic bacteria, control samples without addition of TG and probiotic were produced, as well as the samples without addition of TG but with probiotic bacteria addition. Samples of fresh cheese produced with addition of TG, especially in which TG was active at 11 ºC, had greater weight then samples produced without the enzyme addition. Therefore, their yield was also greater then yield of cheese produced without the addition of the enzyme. Furthermore, the samples of fresh cheese produced with addition of TG have shown lesser syneresis than other samples during 10 days of storage at 10 ºC. The same samples also had the best sensory properties. Metabolic activity of mesophilic culture MM101 and probiotic culture L. acidophilus LAC-1 has resulted in better taste and odour of fresh cheese. The viable cell number of probiotic strain L. acidophilus LAC-1 in prepared samples was around 5 x 106 cells/g after 10 days of storage at 10 ºC, which is higher than the minimal dose required for 27 probiotic products. Addition of transgultaminase contributed to better consistency and general appearance of produced fresh cheese.

  8. Vacuum pyrolysis of waste tires with basic additives.

    Science.gov (United States)

    Zhang, Xinghua; Wang, Tiejun; Ma, Longlong; Chang, Jie

    2008-11-01

    Granules of waste tires were pyrolyzed under vacuum (3.5-10 kPa) conditions, and the effects of temperature and basic additives (Na2CO3, NaOH) on the properties of pyrolysis were thoroughly investigated. It was obvious that with or without basic additives, pyrolysis oil yield increased gradually to a maximum and subsequently decreased with a temperature increase from 450 degrees C to 600 degrees C, irrespective of the addition of basic additives to the reactor. The addition of NaOH facilitated pyrolysis dramatically, as a maximal pyrolysis oil yield of about 48 wt% was achieved at 550 degrees C without the addition of basic additives, while a maximal pyrolysis oil yield of about 50 wt% was achieved at 480 degrees C by adding 3 wt% (w/w, powder/waste tire granules) of NaOH powder. The composition analysis of pyrolytic naphtha (i.b.p. (initial boiling point) approximately 205 degrees C) distilled from pyrolysis oil showed that more dl-limonene was obtained with basic additives and the maximal content of dl-limonene in pyrolysis oil was 12.39 wt%, which is a valuable and widely-used fine chemical. However, no improvement in pyrolysis was observed with Na2CO3 addition. Pyrolysis gas was mainly composed of H2, CO, CH4, CO2, C2H4 and C2H6. Pyrolytic char had a surface area comparable to commercial carbon black, but its proportion of ash (above 11.5 wt%) was much higher.

  9. Promotional effects of new types of additives on fat crystallization.

    Science.gov (United States)

    Yoshikawa, Shinichi; Kida, Haruyasu; Sato, Kiyotaka

    2014-01-01

    We examined the promotional effects of additives on fat crystallization, such as inorganic (talc, carbon nanotube (CNT), and graphite) and organic (theobromine, ellagic acid dihydrate (EAD), and terephthalic acid) materials. The triacylglycerols (TAGs) of trilauroylglycerol (LLL), trimyristoylglycerol (MMM), and tripalmitoylglycerol (PPP) were employed as the fats. The additives (1 wt%) were added to the molten TAGs, and then the mixtures were cooled at a rate of 1°C/min followed by heating at a rate of 5°C/min. The crystallization and melting properties were observed using differential scanning calorimetry, X-ray diffraction, and polarized optical microscope (POM). Consequently, we found that the above six additives remarkably increased the initial temperatures of crystallization (Ti) on cooling without changing the melting temperatures. For example, in the case of LLL, the increases in Ti were 2.6°C (talc), 3.9°C (CNT), 8.1°C (graphite), 1.1°C (theobromine), 2.0°C (EAD), and 6.8°C (terephthalic acid). Very similar effects were observed for the crystallization of MMM and PPP with the six additives. Furthermore, the polymorphs of the first occurring crystals were changed from metastable to more stable forms by many of these additives. The POM observation revealed that the crystallization was initiated at the surfaces of additive particles. This study has shown for the first time that the heterogeneous nucleation of fat crystals can be greatly promoted by new types of additives. Such additives have great potential to promote fat crystallization by not only hydrophobic but also hydrophilic molecular interactions between the fats and additives.

  10. Efficiency enhancement of dye-sensitized solar cells with addition of additives (single/binary) to ionic liquid electrolyte

    Indian Academy of Sciences (India)

    H-S Lee; S-H Bae; C-H Han; S S Sekhon

    2012-11-01

    The effect of addition of single and binary additives on the performance of dye-sensitized TiO2 solar cells based on electrolytes containing an ionic liquid (IL), 1,2-dimethyl-3-propylimidazolium iodide (DMPII) has been studied. Among the seven additives used, the addition of 2-(dimethylamino)-pyridine (DMAP) to IL resulted in best cell efficiency, which showed further enhancement with the addition of 5-chloro-1-ethyl-2-methylimidazole (CEMI) as second additive. The efficiency of the dye-sensitized solar cell (DSC) based on an electrolyte containing binary additives (DMAP and CEMI in equal molar ratios) has been found to increase by 62.5% from 4.35 to 7.07%. The dependence of different photovoltaic performance parameters (\\oc, sc, , ) of DSC upon temperature has been studied over a 30–120°C range and only a small decrease in conversion efficiency has been observed. The electrolyte containing binary additives (DMAP and CEMI) shows best cell performance up to 120°C.

  11. Amine-intercalated α-zirconium phosphates as lubricant additives

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Huaping; Dai, Wei [Department of Mechanical Engineering, Texas A& M University, College Station, TX 77843 (United States); Kan, Yuwei; Clearfield, Abraham [Department of Chemistry, Texas A& M University, College Station, TX 77843 (United States); Liang, Hong, E-mail: hliang@tamu.edu [Department of Mechanical Engineering, Texas A& M University, College Station, TX 77843 (United States)

    2015-02-28

    In this study, three types of amines intercalated α-zirconium phosphate nanosheets with different interspaces were synthesized and examined as lubricant additives to a mineral oil. Results from tribological experiments illustrated that these additives improved lubricating performance. Results of rheological experiments showed that the viscosity of the mineral oil was effectively reduced with the addition of α-zirconium phosphate nanosheets. The two-dimensional structure, with larger interspaces, resulting from amine intercalation, exhibited improved effectiveness in reducing viscosity. This study demonstrates that the nanosheet structure of α-zirconium phosphates is effective in friction reduction. The manufacture of lubricants with tailored viscosity is possible by using different intercalators.

  12. Corn fiber hulls as a food additive or animal feed

    Science.gov (United States)

    Abbas, Charles; Beery, Kyle E.; Cecava, Michael J.; Doane, Perry H.

    2010-12-21

    The present invention provides a novel animal feed or food additive that may be made from thermochemically hydrolyzed, solvent-extracted corn fiber hulls. The animal feed or food additive may be made, for instance, by thermochemically treating corn fiber hulls to hydrolyze and solubilize the hemicellulose and starch present in the corn fiber hulls to oligosaccharides. The residue may be extracted with a solvent to separate the oil from the corn fiber, leaving a solid residue that may be prepared, for instance by aggolmerating, and sold as a food additive or an animal feed.

  13. Effect of additive on the formation of polyacrylonitrile membrane

    Institute of Scientific and Technical Information of China (English)

    YANG Sen; LIU Zhong-zhou

    2004-01-01

    The effect of additives CaCl2 and CaCl2/H2O on the properties of polyacrylonitrile(PAN) ultrafiltration(UF)membranes prepared by phase inversion process was studied. The dissolving capacity of the casting solution forCaCl2 was enhanced by the addition of H2O. The membranes are characterized in terms of the pure water flux andmolecular weight cut-off( MWCO). The addition of CaCl2 or CaCl2/H2O to the casting solution increases the resultingmembrane permeability.

  14. Utilization of Bamboo Charcoal as Additives in Cakes

    Directory of Open Access Journals (Sweden)

    Ronald O. Ocampo

    2015-12-01

    Full Text Available Charcoal has been used for healing various diseases, as antidote to poisoning and as purifying agent to filtered water. This study is conducted to utilize charcoal as additives in making cakes. Specifically, it is intended to determine the acceptable level of charcoal when used as additives in the production of brownies, dark brown chocolate, and chiffon cakes. It can be concluded that an addition of 1 tablespoon of bamboo charcoal gave the highest sensory evaluation to brownies and 3 tablespoon to dark brown chocolate .The control ( no charcoal added is still the best treatment for chiffon cake.

  15. Metal-air cell with performance enhancing additive

    Energy Technology Data Exchange (ETDEWEB)

    Friesen, Cody A; Buttry, Daniel

    2015-11-10

    Systems and methods drawn to an electrochemical cell comprising a low temperature ionic liquid comprising positive ions and negative ions and a performance enhancing additive added to the low temperature ionic liquid. The additive dissolves in the ionic liquid to form cations, which are coordinated with one or more negative ions forming ion complexes. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. The ion complexes improve oxygen reduction thermodynamics and/or kinetics relative to the ionic liquid without the additive.

  16. Comprehensive European dietary exposure model (CEDEM) for food additives.

    Science.gov (United States)

    Tennant, David R

    2016-05-01

    European methods for assessing dietary exposures to nutrients, additives and other substances in food are limited by the availability of detailed food consumption data for all member states. A proposed comprehensive European dietary exposure model (CEDEM) applies summary data published by the European Food Safety Authority (EFSA) in a deterministic model based on an algorithm from the EFSA intake method for food additives. The proposed approach can predict estimates of food additive exposure provided in previous EFSA scientific opinions that were based on the full European food consumption database.

  17. Some new addition formulae for Weierstrass elliptic functions.

    Science.gov (United States)

    Eilbeck, J Chris; England, Matthew; Onishi, Yoshihiro

    2014-11-08

    We present new addition formulae for the Weierstrass functions associated with a general elliptic curve. We prove the structure of the formulae in n-variables and give the explicit addition formulae for the 2- and 3-variable cases. These new results were inspired by new addition formulae found in the case of an equianharmonic curve, which we can now observe as a specialization of the results here. The new formulae, and the techniques used to find them, also follow the recent work for the generalization of Weierstrass functions to curves of higher genus.

  18. >"Disabilities" of Additional Education for Children with Disabilities in Moscow

    Directory of Open Access Journals (Sweden)

    Arzhanyh E.V.,

    2015-10-01

    Full Text Available One of the most significant aspects of social integration of children with special needs is the availability of additional education, which is often the only way to socialize these children. Based on our studies (focus group discussions and a questionnaire survey of 1078 parents of children with special needs we analyzed the limitations of additional education availability for these children according to various criteria (organizational, financial, informational, etc.. Evaluation of the number of children covered by the additional education program leads to the conclusion that the older children are, the harder they get the educational service. The most deprived group are children with intellectual disabilities

  19. Nash Stability in Additively Separable Hedonic Games and Community Structures

    DEFF Research Database (Denmark)

    Olsen, Martin

    2009-01-01

      We prove that the problem of deciding whether a Nash stable   partition exists in an Additively Separable Hedonic Game is   NP-complete. We also show that the problem of deciding whether a   non trivial Nash stable partition exists in an   Additively Separable Hedonic Game with   non......-negative and symmetric   preferences is NP-complete. We motivate our study of the   computational complexity by linking Nash stable partitions in   Additively Separable Hedonic Games to community structures in   networks. Our results formally justify that computing community   structures in general is hard....

  20. Applications of Metal Additive Manufacturing in Veterinary Orthopedic Surgery

    Science.gov (United States)

    Harrysson, Ola L. A.; Marcellin-Little, Denis J.; Horn, Timothy J.

    2015-03-01

    Veterinary medicine has undergone a rapid increase in specialization over the last three decades. Veterinarians now routinely perform joint replacement, neurosurgery, limb-sparing surgery, interventional radiology, radiation therapy, and other complex medical procedures. Many procedures involve advanced imaging and surgical planning. Evidence-based medicine has also become part of the modus operandi of veterinary clinicians. Modeling and additive manufacturing can provide individualized or customized therapeutic solutions to support the management of companion animals with complex medical problems. The use of metal additive manufacturing is increasing in veterinary orthopedic surgery. This review describes and discusses current and potential applications of metal additive manufacturing in veterinary orthopedic surgery.

  1. POTENTIAL HAZARDS DUE TO FOOD ADDITIVES IN ORAL HYGIENE PRODUCTS

    Directory of Open Access Journals (Sweden)

    Damla TUNCER-BUDANUR

    2016-04-01

    Full Text Available Food additives used to preserve flavor or to enhance the taste and appearance of foods are also available in oral hygiene products. The aim of this review is to provide information concerning food additives in oral hygiene products and their adverse effects. A great many of food additives in oral hygiene products are potential allergens and they may lead to allergic reactions such as urticaria, contact dermatitis, rhinitis, and angioedema. Dental practitioners, as well as health care providers, must be aware of the possibility of allergic reactions due to food additives in oral hygiene products. Proper dosage levels, delivery vehicles, frequency, potential benefits, and adverse effects of oral health products should be explained completely to the patients. There is a necessity to raise the awareness among dental professionals on this subject and to develop a data gathering system for possible adverse reactions.

  2. 20 CFR 437.6 - Additions and exceptions.

    Science.gov (United States)

    2010-04-01

    ... Employees' Benefits SOCIAL SECURITY ADMINISTRATION UNIFORM ADMINISTRATIVE REQUIREMENTS FOR GRANTS AND... classes of grants and grantees subject to this part, SSA may not impose additional administrative requirements except in codified regulations published in the Federal Register. (b) Exceptions for classes...

  3. Three additional lizard (Squamata: Sauria records for Mizoram, India

    Directory of Open Access Journals (Sweden)

    H.T. Lalremsanga

    2010-02-01

    Full Text Available We collected three additional species - Calotes maria, Calotes mystaceus and Ophisaurus gracilis which were not recorded previously from Mizoram. Ophisaurus gracilis (Family Anguidae represents a new family for the state.

  4. Overview of current additive manufacturing technologies and selected applications.

    Science.gov (United States)

    Horn, Timothy J; Harrysson, Ola L A

    2012-01-01

    Three-dimensional printing or rapid prototyping are processes by which components are fabricated directly from computer models by selectively curing, depositing or consolidating materials in successive layers. These technologies have traditionally been limited to the fabrication of models suitable for product visualization but, over the past decade, have quickly developed into a new paradigm called additive manufacturing. We are now beginning to see additive manufacturing used for the fabrication of a range of functional end use components. In this review, we briefly discuss the evolution of additive manufacturing from its roots in accelerating product development to its proliferation into a variety of fields. Here, we focus on some of the key technologies that are advancing additive manufacturing and present some state of the art applications.

  5. Additive Manufacturing: Multi Material Processing and Part Quality Control

    DEFF Research Database (Denmark)

    Pedersen, David Bue

    This Ph.D dissertation,ffAdditive Manufacturing: Multi Material Processing and Part Quality Controlff, deal with Additive Manufacturing technologies which is a common name for a series of processes that are recognized by being computer controlled, highly automated, and manufacture objects...... by a layered deposition of material. Two areas of particular interest is addressed. They are rooted in two very different areas, yet is intended to fuel the same goal. To help Additive Manufacturing technologies one step closer to becoming the autonomous, digital manufacturing method of tomorrow. Vision...... systems A paradox exist in the field of Additive Manufacturing. The technologies allow for close-to unrestrained and integral geometrical freedom. Almost any geometry can be manufactured fast, e"ciently and cheap. Something that has been missing fundamental capability since the entering of the industrial...

  6. Additive manufacturing for freeform mechatronics design: from concepts to applications

    NARCIS (Netherlands)

    Baars, G. van; Smeltink, J.; Werff, J. van der; Limpens, M.; Barink, M.; Berg, D. van den; Vreugd, J. de; Witvoet, G.; Galaktionov, O.S.

    2015-01-01

    This article presents developments of freeform mechatronics concepts, enabled by industrial Additive Manufacturing (AM), aiming at breakthroughs for precision engineering challenges such as lightweight, advanced thermal control, and integrated design. To assess potential impact in future application

  7. Role of additional radiotherapy in advanced stages of Hodgkin's disease.

    Science.gov (United States)

    Meerwaldt, J H; Coleman, C N; Fischer, R I; Lister, T A; Diehl, V

    1992-09-01

    Although radiotherapy is widely used as additional treatment following chemotherapy, its precise role has never been clearly proven. Relapses tend to occur in previously involved bulky sites. Non-randomized studies may suggest a positive effect of the addition of radiotherapy. This effect however, might also be caused by selection. Randomized studies have not resulted in a survival advantage for the patients treated with additional radiotherapy compared to no further treatment or additional chemotherapy. The SWOG study 7808 suggest a 20% benefit in remission duration for the nodular sclerosis histology subgroup. Definitive conclusions have to wait for more mature results of randomized studies including the ongoing EORTC study and the possibility to perform an overview of all studies.

  8. Use of Vitelline Protein B as a Microencapsulating Additive

    Science.gov (United States)

    Ficht, Allison R. (Inventor); Carson, Ken (Inventor); Sheffield, Cynthia (Inventor); Waite, John Herbert (Inventor)

    2017-01-01

    The present invention includes compositions and methods for the use of an encapsulation additive having between about 0.1 to about 30 percent isolated and purified vitelline protein B to provide for mixed and extended release formulations.

  9. Assessment of Gasoline Additive Containing Ditert-butoxypropanol

    Energy Technology Data Exchange (ETDEWEB)

    West, Brian H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Connatser, Raynella M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lewis, Samuel Arthur [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    The Fuels, Engines, and Emissions Research Center completed analysis and testing of the CPS Powershot gasoline additive under the auspices of the Department of Energy’s Technical Assistance for US Small Businesses in Vehicle Technologies. Gas chromatography-mass spectrometry (GC-MS) was used to quantify the makeup of the additive, finding a predominance of 2,3-Ditert-Butoxypropanol, also known as Glyceryl Di-Tert-Butyl Ether (GTBE). Blends of the additive at 2 and 4 volume percent were subjected to a number of standard ASTM tests, including Research Octane Number, Motor Octane Number, distillation, and vapor pressure. Results show a high boiling range and low vapor pressure for the additive, and a very modest octane boosting effect in gasoline with and without ethanol.

  10. The Influence of Additives on Crystallization of Polyvinyl Chloride

    Institute of Scientific and Technical Information of China (English)

    LIU Yaqun; ZHANG Chaocan

    2007-01-01

    Acetanilide, adipic acid and potassium hydrogen phthalate were chosen as nucleating agents of polyvinyl chloride(PVC), and their effects on PVC crystallization were studied by differential scanning calorimetry, wide angle X-ray diffraction and fourier transform infrared spectroscopy. The experimental results indicate that all of the three additives are compatible with PVC to some extent, but adipic acid's compatibility with PVC is less satisfactory. The three additives can improve PVC crystallinity, and acetanilide can decrease PVC glass transition temperature(Tg)and narrow PVC melting range, while adipic acid and potassium hydrogen phthalate rise Tg of PVC and widen its melting range. All additives do not affect PVC crystal system and all samples are in orthorhombic system. All additives can improve (200), (110), (210) and (201, 111) planes growing. Moreover, acetanilide and adipic acid can shrink PVC spacings and improve the crystal perfection of PVC, but potassium hydrogen phthalate swells spacings and reduces the perfection of PVC crystal.

  11. 76 FR 18188 - Procurement List; Proposed Additions and Deletions

    Science.gov (United States)

    2011-04-01

    ... following products and service are proposed for addition to Procurement List for production by the nonprofit agencies listed: Products Towel, Highly Absorbent, Synthetic ``Shammy'' NSN: 7920-01-215-6568--15x15....

  12. 75 FR 21244 - Procurement List; Proposed Additions and Deletions

    Science.gov (United States)

    2010-04-23

    ... proposed for addition to Procurement List for production by the nonprofit agencies listed: Products NSN: MR 987--Towel, Super Absorbent, Orange. NSN: MR 988--Towel, Super Absorbent, Kitchen Set, Assorted...

  13. Systematic tests for position-dependent additive shear bias

    CERN Document Server

    van Uitert, Edo

    2016-01-01

    We present new tests to identify stationary position-dependent additive shear biases in weak gravitational lensing data sets. These tests are important diagnostics for currently ongoing and planned cosmic shear surveys, as such biases induce coherent shear patterns that can mimic and potentially bias the cosmic shear signal. The central idea of these tests is to determine the average ellipticity of all galaxies with shape measurements in a grid in the pixel plane. The distribution of the absolute values of these averaged ellipticities can be compared to randomized catalogues; a difference points to systematics in the data. In addition, we introduce a method to quantify the spatial correlation of the additive bias, which suppresses the contribution from cosmic shear and therefore eases the identification of a position-dependent additive shear bias in the data. We apply these tests to the publicly available shear catalogues from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) and the Kilo Degree Su...

  14. Cohomology of exact categories and (non-)additive sheaves

    CERN Document Server

    Kaledin, Dmitry

    2011-01-01

    We use (non-)additive sheaves to introduce an (absolute) notion of Hochschild cohomology for exact categories as Ext's in a suitable bisheaf category. We compare our approach to various definitions present in the literature.

  15. In-Process Monitoring of Additive Manufacturing Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The key innovation in this project is the implementation of an Imaging Fourier Transform Spectrometer (IFTS) for in situ metal additive manufacturing process...

  16. Laser additive manufacturing of high-performance materials

    CERN Document Server

    Gu, Dongdong

    2015-01-01

    This book entitled “Laser Additive Manufacturing of High-Performance Materials” covers the specific aspects of laser additive manufacturing of high-performance new materials components based on an unconventional materials incremental manufacturing philosophy, in terms of materials design and preparation, process control and optimization, and theories of physical and chemical metallurgy. This book describes the capabilities and characteristics of the development of new metallic materials components by laser additive manufacturing process, including nanostructured materials, in situ composite materials, particle reinforced metal matrix composites, etc. The topics presented in this book, similar as laser additive manufacturing technology itself, show a significant interdisciplinary feature, integrating laser technology, materials science, metallurgical engineering, and mechanical engineering. This is a book for researchers, students, practicing engineers, and manufacturing industry professionals interested i...

  17. Ultrasonic Additive Manufacturing for Lightweight Metallic Structures Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this program is to demonstrate the use of UAM to additively build reinforcement structures to reinforce cut outs in larger aluminum structural...

  18. Improvements in floating point addition/subtraction operations

    Energy Technology Data Exchange (ETDEWEB)

    Farmwald, P.M.

    1984-02-24

    Apparatus is described for decreasing the latency time associated with floating point addition and subtraction in a computer, using a novel bifurcated, pre-normalization/post-normalization approach that distinguishes between differences of floating point exponents.

  19. Porosity of additive manufacturing parts for process monitoring

    Science.gov (United States)

    Slotwinski, J. A.; Garboczi, E. J.

    2014-02-01

    Some metal additive manufacturing processes can produce parts with internal porosity, either intentionally (with careful selection of the process parameters) or unintentionally (if the process is not well-controlled.) Material porosity is undesirable for aerospace parts - since porosity could lead to premature failure - and desirable for some biomedical implants, since surface-breaking pores allow for better integration with biological tissue. Changes in a part's porosity during an additive manufacturing build may also be an indication of an undesired change in the process. We are developing an ultrasonic sensor for detecting changes in porosity in metal parts during fabrication on a metal powder bed fusion system, for use as a process monitor. This paper will describe our work to develop an ultrasonic-based sensor for monitoring part porosity during an additive build, including background theory, the development and detailed characterization of reference additive porosity samples, and a potential design for in-situ implementation.

  20. Relative Stabilities of Organic Compounds Using Benson's Additivity Rules.

    Science.gov (United States)

    Vitale, Dale E.

    1986-01-01

    Shows how the structure-energy principle can be presented in organic chemistry (without having to resort to quantum mechanics) by use of Benson's Additive Rules. Examples of the application to several major classes of organic compounds are given.

  1. Advances in 3D printing & additive manufacturing technologies

    CERN Document Server

    Pandey, Pulak; Kumar, L

    2017-01-01

    This edited volume comprises select chapters on advanced technologies for 3D printing and additive manufacturing and how these technologies have changed the face of direct, digital technologies for rapid production of models, prototypes and patterns. Because of its wide applications, 3D printing and additive manufacturing technology has become a powerful new industrial revolution in the field of manufacturing. The evolution of 3D printing and additive manufacturing technologies has changed design, engineering and manufacturing processes across industries such as consumer products, aerospace, medical devices and automotives. The objective of this book is to help designers, R&D personnel, and practicing engineers understand the state-of-the-art developments in the field of 3D Printing and Additive Manufacturing. .

  2. Nitrosonium (NO+) catalyzed Michael addition of indoles to unsaturated enones

    Institute of Scientific and Technical Information of China (English)

    Guai Li Wu; Long Min Wu

    2008-01-01

    An efficient Michael addition of indoles to unsaturated enones, such as chalcones and β-nitrostyrenes, was achieved in thepresence of a catalytic amount of nitrosoninm tetrafluoroborate in ethyl ether.

  3. Efficient improvement of silage additives by using genetic algorithms.

    Science.gov (United States)

    Davies, Z S; Gilbert, R J; Merry, R J; Kell, D B; Theodorou, M K; Griffith, G W

    2000-04-01

    The enormous variety of substances which may be added to forage in order to manipulate and improve the ensilage process presents an empirical, combinatorial optimization problem of great complexity. To investigate the utility of genetic algorithms for designing effective silage additive combinations, a series of small-scale proof of principle silage experiments were performed with fresh ryegrass. Having established that significant biochemical changes occur over an ensilage period as short as 2 days, we performed a series of experiments in which we used 50 silage additive combinations (prepared by using eight bacterial and other additives, each of which was added at six different levels, including zero [i.e. , no additive]). The decrease in pH, the increase in lactate concentration, and the free amino acid concentration were measured after 2 days and used to calculate a "fitness" value that indicated the quality of the silage (compared to a control silage made without additives). This analysis also included a "cost" element to account for different total additive levels. In the initial experiment additive levels were selected randomly, but subsequently a genetic algorithm program was used to suggest new additive combinations based on the fitness values determined in the preceding experiments. The result was very efficient selection for silages in which large decreases in pH and high levels of lactate occurred along with low levels of free amino acids. During the series of five experiments, each of which comprised 50 treatments, there was a steady increase in the amount of lactate that accumulated; the best treatment combination was that used in the last experiment, which produced 4.6 times more lactate than the untreated silage. The additive combinations that were found to yield the highest fitness values in the final (fifth) experiment were assessed to determine a range of biochemical and microbiological quality parameters during full-term silage fermentation. We

  4. ABOUT FOOD ADDITIVES AS IMPORTANT PART OF FUNCTIONAL FOOD

    OpenAIRE

    Umida Khodjaeva; Tatiana Bojňanská; Vladimír Vietoris; Oksana Sytar

    2013-01-01

    The main characteristics and classification of food additives, which are common in the food production, have been described in the present review. The ways of food additives classification, source of nature, main antioxidants, food colouring, flavours, flavor enhancers, bulking agents, stabilizers, sweeteners which were collected from literature based on structural and biochemical characteristics with description of source and possible effects on human, organisms and environment have been pre...

  5. Additives for Water Mist Fire Suppression Systems: A Review

    Science.gov (United States)

    2012-11-01

    languages unless the text is bilingual .) The use of both fixed and portable water mist systems for fire suppression on naval vessels continues to... seconds . The FFFP additive gave the best burnback performance (longest burnback time) in sea water and the second best time in fresh water. The burnback...diesel fuel) fire decreased from 175 seconds to 8 seconds when the additive was used and an Avtur (aviation turbine fuel) fire that was not

  6. Further Results on Dynamic Additive Hazard Rate Model

    Directory of Open Access Journals (Sweden)

    Zhengcheng Zhang

    2014-01-01

    Full Text Available In the past, the proportional and additive hazard rate models have been investigated in the works. Nanda and Das (2011 introduced and studied the dynamic proportional (reversed hazard rate model. In this paper we study the dynamic additive hazard rate model, and investigate its aging properties for different aging classes. The closure of the model under some stochastic orders has also been investigated. Some examples are also given to illustrate different aging properties and stochastic comparisons of the model.

  7. Students' Understanding of the Addition of Angular Momentum

    CERN Document Server

    Singh, Chandralekha

    2016-01-01

    We describe the difficulties advanced undergraduate and graduate students have with concepts related to the addition of angular momentum. We also describe the development and implementation of a research-based learning tool, a Quantum Interactive Learning Tutorial (QuILT), to reduce these difficulties. The preliminary evaluation shows that the QuILT on the addition of angular momentum is helpful in improving students' understanding of these concepts.

  8. Ionic Liquids as Novel Lubricants and /or Lubricant Additives

    Energy Technology Data Exchange (ETDEWEB)

    Qu, J. [ORNL; Viola, M. B. [General Motors Company

    2013-10-31

    This ORNL-GM CRADA developed ionic liquids (ILs) as novel lubricants or oil additives for engine lubrication. A new group of oil-miscible ILs have been designed and synthesized with high thermal stability, non-corrosiveness, excellent wettability, and most importantly effective anti-scuffing/anti-wear and friction reduction characteristics. Mechanistic analysis attributes the superior lubricating performance of IL additives to their physical and chemical interactions with metallic surfaces. Working with a leading lubricant formulation company, the team has successfully developed a prototype low-viscosity engine oil using a phosphonium-phosphate IL as an anti-wear additive. Tribological bench tests of the IL-additized formulated oil showed 20-33% lower friction in mixed and elastohydrodynamic lubrication and 38-92% lower wear in boundary lubrication when compared with commercial Mobil 1 and Mobil Clean 5W-30 engine oils. High-temperature, high load (HTHL) full-size engine tests confirmed the excellent anti-wear performance for the IL-additized engine oil. Sequence VID engine dynamometer tests demonstrated an improved fuel economy by >2% for this IL-additized engine oil benchmarked against the Mobil 1 5W-30 oil. In addition, accelerated catalyst aging tests suggest that the IL additive may potentially have less adverse impact on three-way catalysts compared to the conventional ZDDP. Follow-on research is needed for further development and optimization of IL chemistry and oil formulation to fully meet ILSAC GF-5 specifications and further enhance the automotive engine efficiency and durability.

  9. Copper electrodeposition and additives: from underpotential deposition to bulk growth

    Energy Technology Data Exchange (ETDEWEB)

    Yanson, Yuriy; Frenken, Joost; Rost, Marcel [Leiden University, Leiden (Netherlands)

    2011-07-01

    Cu electrodeposition at different stages on Au(111) surface is accessed in-situ on atomic scale by means of our newly developed fast electrochemical STM. We show the effect of industrially used additives, such as bis-(3-sodiumsulfopropyl) disulfide (SPS) and polyethylene glycol (PEG), on the Cu deposit. The EC-STM results are complemented by electrochemical measurements and discussed in the light of current state of knowledge on electrodeposition and molecular processes involving the additives.

  10. A Simple Experimental Setup for Teaching Additive Colors with Arduino

    Science.gov (United States)

    Carvalho, Paulo Simeão; Hahn, Marcelo

    2016-01-01

    The result of additive colors is always fascinating to young students. When we teach this topic to 14- to 16-year-old students, they do not usually notice we use maximum light quantities of red (R), green (G), and blue (B) to obtain yellow, magenta, and cyan colors in order to build the well-known additive color diagram of Fig. 1. But how about…

  11. Multiple material additive manufacturing – Part 1:\\ud a review

    OpenAIRE

    Vaezi, Mohammad; Chianrabutra, Srisit; Mellor, Brian; Yang, Shoufeng

    2013-01-01

    Interest in multifunctional structures made automatically from multiple materials poses a challenge for today’s additive manufacturing (AM) technologies; however the ability to process multiple materials is a fundamental advantage to some AM technologies. The capability to fabricate multiple material parts can improve AM technologies by either optimizing the mechanical properties of the parts or providing additional functions to the final parts. The objective of this paper is to give an overv...

  12. SUNFLOWER HUSKS AS A SOURCE OF FUNCTIONAL FEED ADDITIVES

    OpenAIRE

    Khusid S. B.; Gneush A. N.; Nesterenko E. E.

    2015-01-01

    The article describes the results of the complex feed additive based on sunflower husk, enriched with beer wort with the addition of pumpkin pulp. We have studied the chemical composition of sunflower husk, which is the secondary resource of the processing plant raw material, selected methods of enrichment of this raw material with the help of fungi Trichoderma harzianum. Cellulolytic enzyme preparations on the basis of fungi of the genus Trichoderma for use in agriculture and animal feed pro...

  13. Sintering nanodisperse zirconium powders with various stabilizing additives

    Directory of Open Access Journals (Sweden)

    Antsiferov V.N.

    2011-01-01

    Full Text Available Effect of various stabilizing additives on sintering kinetics of nanodisperse powders was studied by thermomechanical analysis. Temperature ranges of the most intense shrinking, characteristic points of shrinking rate changes were established. Peaks characterizing the most intense shrinking of nanodisperse zirconium powder samples were shown to allow to arrange the stabilizing additives as follows: Y2O3→CeO2→TiO2.

  14. The Additional Interpolators Method for Variational Analysis in Lattice QCD

    CERN Document Server

    Schiel, Rainer W

    2015-01-01

    In this paper, I describe the Additional Interpolators Method, a new technique for variational analysis in lattice QCD. It is shown to be an excellent method which uses additional interpolators to remove backward in time running states that would otherwise contaminate the signal. The proof of principle, which also makes use of the Time-Shift Trick (Generalized Pencil-of-Functions method), will be delivered at an example on a $64^4$ lattice close to the physical pion mass.

  15. Sustainable Production Process of Biological Mineral Feed Additives

    OpenAIRE

    Agnieszka Zielinska; Katarzyna Chojnacka; Marjana Simonic

    2009-01-01

    Problem statement: This study discussed the problem of accumulation of Zn and Cu in the topsoil as a result of application of mineral feed additives that possess low bioavailability in animal diet. The review considered the production process of mineral feed additives in which a product supplies microelements in highly bioavailable form. Enrichment of natural biomass of edible microalgae with microelement metal ions, which supply microelements of feeding significance in livestock diet, is con...

  16. Correlation additivity relation is superadditive for separable states

    CERN Document Server

    Zhang, Zhanjun

    2012-01-01

    We deny with a concrete example the generality of the correlation subadditivity relation conjectured by Modi et al's [Phys. Rev. Lett. {\\bf 104}, 080501 (2010)] for any quantum state and point out that the correlation additivity relation is actually super-additive for separable states. This work indicates that any effort on explicitly proving the conjecture and finding the subadditivity source is unnecessary and fruitless.

  17. Alternative proofs for Kocik's Geometric Diagram for Relativistic Velocity Addition

    CERN Document Server

    Sasane, Amol

    2015-01-01

    A geometric construction for the Poincare formula for relativistic addition of velocities in one dimension was given by Jerzy Kocik in "Geometric Diagram for Relativistic Addition of Velocities", American Journal of Physics, volume 80, page 737, 2012. While the proof given there used Cartesian coordinate geometry, three alternative approaches are given in this article: a trigonometric one, one via Euclidean geometry, and one using projective geometry.

  18. Current Fluctuations in Nonequilibrium Diffusive Systems: An Additivity Principle

    Science.gov (United States)

    Bodineau, T.; Derrida, B.

    2004-05-01

    We formulate a simple additivity principle allowing one to calculate the whole distribution of current fluctuations through a large one dimensional system in contact with two reservoirs at unequal densities from the knowledge of its first two cumulants. This distribution (which in general is non-Gaussian) satisfies the Gallavotti-Cohen symmetry and generalizes the one predicted recently for the symmetric simple exclusion process. The additivity principle can be used to study more complex diffusive networks including loops.

  19. LEAN ORGANIZATION OF ADDITIVE MANUFACTURING OF AIRCRAFT PURPOSE PRODUCTS

    Directory of Open Access Journals (Sweden)

    Smelov V.G

    2014-10-01

    Full Text Available This study considers the question of creation of a modern small aircraft purpose parts manufacturing company which will use additive technologies according to the principles of "smart" production and the concept of «lean» management. In order to reduce time and cost of current production, conform to world technologies and competitive ability optimization of key business processes of the foundry was carried out with adoption of a model of additive manufacturing.

  20. LEAN ORGANIZATION OF ADDITIVE MANUFACTURING OF AIRCRAFT PURPOSE PRODUCTS

    OpenAIRE

    Smelov V.G; Kokareva V.V; Malykhin A.N

    2014-01-01

    This study considers the question of creation of a modern small aircraft purpose parts manufacturing company which will use additive technologies according to the principles of "smart" production and the concept of «lean» management. In order to reduce time and cost of current production, conform to world technologies and competitive ability optimization of key business processes of the foundry was carried out with adoption of a model of additive manufacturing.

  1. Contamination effects of drilling fluid additives on cement slurry

    Directory of Open Access Journals (Sweden)

    Youzhi Zheng

    2015-10-01

    Full Text Available During the cementation of deep wells, contamination at the contact surface between cement slurry and drilling fluid will present a technical challenge, which may threaten operation safety. To deal with the problem, lab tests and analysis were performed specifically on the compatibility of fluids during cementation in Sichuan and Chongqing gas fields. Impacts of commonly used additives for drilling fluids were determined on fluidity and thickening time of conventional cement slurry. Through the infrared spectrum analysis, SEM and XRD, infrared spectrum data of kalium polyacrylamide (KPAM and bio-viscosifier were obtained, together with infrared spectrum, SEM and XRD data of cement slurry with additives. Contamination mechanisms of the cement slurry by conventional additives for drilling fluid were reviewed. Test results show that both KPAM and bio-viscosifier are such high-molecular materials that the long chains in these materials may easily absorb cement particles in the slurry to form mixed network structures; as a result, cement particles were prone to agglomeration and eventually lost their pumpability. Finally, assessment of and testing methods for the contamination effects of drilling fluid additives on cement slurry were further improved to form standards and codes that may help solve the said problems. This study will provide technological supports for the preparation of drilling fluids with desirable properties prior to cementation, the selection of optimal drilling fluids additives, and the development of innovative drilling fluids additives.

  2. Evaluation of relative biological efficiency of additives in sugarcane ensiling

    Directory of Open Access Journals (Sweden)

    Laura Maria Oliveira Borgatti

    2012-04-01

    Full Text Available The objective of this study was to evaluate the effects of adding alkalis on the fermentative pattern, aerobic stability and nutritive value of the sugarcane silage. A completely randomized design with 6 additives in two concentrations (1 or 2%, plus a control group, totalizing 13 treatments [(6×2+1] with four replications, was used. The additives were sodium hydroxide (NaOH, limestone (CaCO3, urea (CO(NH22, sodium bicarbonate (NaHCO3, quicklime (CaO and hydrated lime (Ca(OH2. The material was ensiled in 52 laboratory silos using plastic buckets with 12 L of capacity. Silos were opened 60 days after ensiling, when organic acids concentration, aerobic stability and chemical composition were determined. The Relative Biological Efficiency (RBE was calculated by the slope ratio method, using the data obtained from ratio between desirable and undesirable silage products, according to the equation: D/U ratio = [lactic/(ethanol + acetic + butyric]. All additives affected dry matter, crude protein, acid detergent fiber, neutral detergent fiber contents and buffering capacity. Except for urea and quicklime, all additives increased the in vitro dry matter digestibility. In general, these additives altered the fermentative pattern of sugarcane silage, inhibiting alcoholic fermentation and improving lactic acid production. The additive that showed the best RBE in relation to sodium hydroxide (100% was limestone (89.4%. The RBE values of urea, sodium bicarbonate and hydrated lime were 49.2%, 47.7% and 34.3%, respectively.

  3. Dry building mixture with complex dispersed mineral additives

    Science.gov (United States)

    Il'ina, Liliia; Mukhina, Irina; Teplov, Alexandr

    2016-01-01

    The effectiveness of the complex dispersed mineral additive consisting of diopside and limestone was provided by the following factors. Diopside, due to the high hardness, reinforces formed hardened cement paste and prevents the spread of micro-cracks in it under the action of loads. Furthermore, diopside due to the greater elastic modulus than cement paste causes redistribution of stress between the additive particles and the cement. Limestone, since it has chemical affinity with the clinker minerals and products of their hydration hardening, effects on the hydration process and the formation of the contact area between the additive particles and the cement. The optimum quantity of complex dispersed mineral additive is 7%. At the same time the strength of the solution, made of dry building mixture "rough leveler for floor", increased by 22.1%, and the strength of the solution, made of dry mortar "masonry mixture" increased by 32.7%. With the mineral additive introduction the offset of the endoeffect temperatures to higher temperatures on derivatograms is fixed. If there is a mineral additive in the hardened cement paste, which may act as substrate for the tumors crystallization, the hardened cement paste structure strengthening while the complex thermal analysis is seen.

  4. Basophil activation test with food additives in chronic urticaria patients.

    Science.gov (United States)

    Kang, Min-Gyu; Song, Woo-Jung; Park, Han-Ki; Lim, Kyung-Hwan; Kim, Su-Jung; Lee, Suh-Young; Kim, Sae-Hoon; Cho, Sang-Heon; Min, Kyung-Up; Chang, Yoon-Seok

    2014-01-01

    The role of food additives in chronic urticaria (CU) is still under investigation. In this study, we aimed to explore the association between food additives and CU by using the basophil activation test (BAT). The BAT using 15 common food additives was performed for 15 patients with CU who had a history of recurrent urticarial aggravation following intake of various foods without a definite food-specific IgE. Of the 15 patients studied, two (13.3%) showed positive BAT results for one of the tested food additives. One patient responded to monosodium glutamate, showing 18.7% of CD203c-positive basophils. Another patient showed a positive BAT result to sodium benzoate. Both patients had clinical correlations with the agents, which were partly determined by elimination diets. The present study suggested that at least a small proportion of patients with CU had symptoms associated with food additives. The results may suggest the potential utility of the BAT to identity the role of food additives in CU.

  5. Additives for cement compositions based on modified peat

    Energy Technology Data Exchange (ETDEWEB)

    Kopanitsa, Natalya, E-mail: kopanitsa@mail.ru; Sarkisov, Yurij, E-mail: sarkisov@tsuab.ru; Gorshkova, Aleksandra, E-mail: kasatkina.alexandra@gmail.com; Demyanenko, Olga, E-mail: angel-n@sibmail.com [Tomsk State University of Architecture and Building, 2, Solyanaya sq., Tomsk, 634003 (Russian Federation)

    2016-01-15

    High quality competitive dry building mixes require modifying additives for various purposes to be included in their composition. There is insufficient amount of quality additives having stable properties for controlling the properties of cement compositions produced in Russia. Using of foreign modifying additives leads to significant increasing of the final cost of the product. The cost of imported modifiers in the composition of the dry building mixes can be up to 90% of the material cost, depending on the composition complexity. Thus, the problem of import substitution becomes relevant, especially in recent years, due to difficult economic situation. The article discusses the possibility of using local raw materials as a basis for obtaining dry building mixtures components. The properties of organo-mineral additives for cement compositions based on thermally modified peat raw materials are studied. Studies of the structure and composition of the additives are carried out by physicochemical research methods: electron microscopy and X-ray analysis. Results of experimental research showed that the peat additives contribute to improving of cement-sand mortar strength and hydrophysical properties.

  6. Additives for cement compositions based on modified peat

    Science.gov (United States)

    Kopanitsa, Natalya; Sarkisov, Yurij; Gorshkova, Aleksandra; Demyanenko, Olga

    2016-01-01

    High quality competitive dry building mixes require modifying additives for various purposes to be included in their composition. There is insufficient amount of quality additives having stable properties for controlling the properties of cement compositions produced in Russia. Using of foreign modifying additives leads to significant increasing of the final cost of the product. The cost of imported modifiers in the composition of the dry building mixes can be up to 90% of the material cost, depending on the composition complexity. Thus, the problem of import substitution becomes relevant, especially in recent years, due to difficult economic situation. The article discusses the possibility of using local raw materials as a basis for obtaining dry building mixtures components. The properties of organo-mineral additives for cement compositions based on thermally modified peat raw materials are studied. Studies of the structure and composition of the additives are carried out by physicochemical research methods: electron microscopy and X-ray analysis. Results of experimental research showed that the peat additives contribute to improving of cement-sand mortar strength and hydrophysical properties.

  7. Tribological performance of organic cadmium compound as lubricant additive

    Institute of Scientific and Technical Information of China (English)

    HU Jian-qiang; XIE Feng; ZHU Huan-qin; ZHEN Fa-zheng; YAO Jun-bing

    2004-01-01

    The oil-soluble cadmium dipropyldithiophosphate additive was synthesized. A four-ball tester was used to evaluate the tribological performance of the additive in a mineral oil under different loads and lubricant grease synthesized compared with some commercial additives. The results show that it exhibits excellent antiwear and load-carrying capacities and is better than other additives. The surface analytical tools such as scanning electron microscope (SEM) with energy dispersive X-ray (EDX), X-ray photoelectron spectrometer (XPS) were used to investigate the topography, the compositions, and chemical states of some typical elements on the rubbing surface of worn scar.Smooth and light topography of worn scar further confirms that the additive shows good antiwear capacities. The results of EDX and XPS analyses indicate that tribochemical mixed protective films consisting of atomic cadmium, sulphides, sulphates and phosphates are formed on the rubbing surface, which contribute to improving the tribological properties of lubricant and grease. Particularly, the soft cadmium film formed plays an important role in improving antiwear properties of oils. Finally, antiwear mechanism of the additive and formation scheme of atomic cadmium was proposed.

  8. APPLIED RESEARCH ON NEW MULTI-FUNCTION GASOLINE ADDITIVE

    Institute of Scientific and Technical Information of China (English)

    CAI Ruibin; MING Caibing; GAO Zhiwen

    2006-01-01

    In order to assess the performance of a new cleansing and combustion-improving gasoline additive (MAZ), and to explore the evaluation methods of additives, two engines with the same model number and performance indices, fueled with and without the MAZ gasoline additive respectively, are carried through 100 h strenuous tests on a bench. The results obtained in full load characteristic and load characteristics of different operational modes are compared. It indicates that the power, economy and emission of the engine fueled with the MAZ additive all have obvious improvement in comparison with the engine without adding the additive: the power increasing by 16.43%, specific fuel consumption (SFC) decreasing 5.39%, and the emission of CO, HC and NOx falling by 28.61%, 54.38%and 10.1% respectively. Wear and tear of the engine cylinder is weakened, and sediment of combustion chamber inner side is reduced. In addition, no negative effect on the catalytic conversion device is found.

  9. Fitting Additive Binomial Regression Models with the R Package blm

    Directory of Open Access Journals (Sweden)

    Stephanie Kovalchik

    2013-09-01

    Full Text Available The R package blm provides functions for fitting a family of additive regression models to binary data. The included models are the binomial linear model, in which all covariates have additive effects, and the linear-expit (lexpit model, which allows some covariates to have additive effects and other covariates to have logisitc effects. Additive binomial regression is a model of event probability, and the coefficients of linear terms estimate covariate-adjusted risk differences. Thus, in contrast to logistic regression, additive binomial regression puts focus on absolute risk and risk differences. In this paper, we give an overview of the methodology we have developed to fit the binomial linear and lexpit models to binary outcomes from cohort and population-based case-control studies. We illustrate the blm packages methods for additive model estimation, diagnostics, and inference with risk association analyses of a bladder cancer nested case-control study in the NIH-AARP Diet and Health Study.

  10. Additives in crude oil. A new attempt to prevent boilover; Additive im Rohoel. Ein neuer Ansatz zur Vermeidung eines Boilover

    Energy Technology Data Exchange (ETDEWEB)

    Gosewinkel, Martin; Dworschak, Rene [INBUREX Consulting GmbH, Hamm (Germany)

    2011-03-15

    Boilover of tanks is a rare cause of serious fires in crude oil storage. The greatest danger is the spill of burning material from the tank. In the research project presented here, a method to prevent boilover and/or reduce its effects was to be developed. One approach is the addition of additives that modify the hetero-azeotropic boiling characteristics of crude oil components in case of fire. Even minimum concentrations of the additive will delay the time until boilover and also reduce its intensity.

  11. Control of microbial corrosion using coatings and natural additives

    Energy Technology Data Exchange (ETDEWEB)

    Al-Darbi, M.M.; Muntasser, Z.M.; Tango, M.; Islam, M.R.

    2002-11-01

    One of the major concerns in the oil and gas industry is corrosion. Microbial-influenced corrosion (MIC) can be defined as the deterioration of metals by natural processes directly or indirectly related to the activity of microorganisms. MIC affects many industries, such as petrochemical, ships and marine structures, power generating, aircraft fuel systems, waste water facilities, cooling water systems, process industries, paper mills, and water supply and distribution systems. In this study, the influence of sulfate-reducing bacteria (SRB), grown in a lactate/ sulfate culture medium, on the corrosion of both uncoated and coated mild steel was evaluated in the presence and absence of natural additives. To achieve this, an oil based coating (alkyd) was used with and without the addition of natural additives to protect mild steel in a sulfate-reducing bacteria environment. Another objective of this study was to investigate the effects of SRB and/or their metabolites on the used coatings and the adverse effects of those coatings and additives on biofilm formation and bacteria growth rate. In this paper, 2 natural additives were identified for effective MIC protection. Natural products were selected based on the environmental appeal of the products. Two additives, derived from olive oil and Manhaden fish oil, were found to be effective in reducing MIC. In general, 2-3% of a natural additive was deemed adequate for effective MIC protection. Bacteria populations were counted at the beginning and at the end of the tests using the plate count method. After immersing the different coupons for 3 months in the SRB medium, it was noticed that the number of bacteria and their colonies were highly affected by both the environment and the used coating systems. A series of corrosion tests was performed to study the effectiveness of various natural additives. Visual observations, scanning electron microscopy (SEM) analyses, and computer image analyzer techniques were used to study

  12. Characterization of Metal Powders Used for Additive Manufacturing.

    Science.gov (United States)

    Slotwinski, J A; Garboczi, E J; Stutzman, P E; Ferraris, C F; Watson, S S; Peltz, M A

    2014-01-01

    Additive manufacturing (AM) techniques can produce complex, high-value metal parts, with potential applications as critical parts, such as those found in aerospace components. The production of AM parts with consistent and predictable properties requires input materials (e.g., metal powders) with known and repeatable characteristics, which in turn requires standardized measurement methods for powder properties. First, based on our previous work, we assess the applicability of current standardized methods for powder characterization for metal AM powders. Then we present the results of systematic studies carried out on two different powder materials used for additive manufacturing: stainless steel and cobalt-chrome. The characterization of these powders is important in NIST efforts to develop appropriate measurements and standards for additive materials and to document the property of powders used in a NIST-led additive manufacturing material round robin. An extensive array of characterization techniques was applied to these two powders, in both virgin and recycled states. The physical techniques included laser diffraction particle size analysis, X-ray computed tomography for size and shape analysis, and optical and scanning electron microscopy. Techniques sensitive to structure and chemistry, including X-ray diffraction, energy dispersive analytical X-ray analysis using the X-rays generated during scanning electron microscopy, and X-Ray photoelectron spectroscopy were also employed. The results of these analyses show how virgin powder changes after being exposed to and recycled from one or more Direct Metal Laser Sintering (DMLS) additive manufacturing build cycles. In addition, these findings can give insight into the actual additive manufacturing process.

  13. Antifreeze polymeric additives for fuels; Aditivos polimericos anticongelantes para combustiveis

    Energy Technology Data Exchange (ETDEWEB)

    Muniz, Aline S.; Carvalho, Agne Roani de; Sakae, George Hideki; Oliveira, Angelo R.S.; Cesar-Oliveira, Maria Aparecida F. [Universidade Federal do Parana - UFPR - Departamento de Quimica - LABPOL-Laboratorio de Polimeros Sinteticos, Centro Politecnico, Curitiba, PR (Brazil)], e-mails: mafco@ufpr.br, alinemuniz@ufpr.br

    2011-07-01

    Owing to the current interest in the reduction of environmental pollution, several researchers are seeking renewable sources of energy which can at least partially replace combustibles derived from petroleum. Diesel oil is the combustible that most seriously pollutes the environment and is thus the biodiesel that is being considered as a fuel which can be replaced by a renewable combustible; this can possibly be used in diesel engines without any modifications. However, certain problems have to be overcome with regard to the temperature at which the biodiesel should be stored and used, since there is a tendency for biodiesel to solidify at low temperatures. This suggests that there is a need for the use of anti-freeze additives. This work behind the main focus additives with only 25 ppm, were able to reduce the pour point of fuel, achieving significant results, for example, the additive M14A18 lowered the pour point (PP) of B20 to -20 degree C, showing that the use of increasing amounts of biodiesel to diesel can aggregate. The main focus of work behind the development of additives that with only 25 ppm, were able to reduce the pour point of fuel, producing significant results such as those obtained with the use of additive M14A18 which lowered the pour point of the B20 to -20 degree C, showing the possibility of using increasing amounts of biodiesel added to diesel. (author)

  14. Enhancing thermostability of β-mannanase by protective additives

    Institute of Scientific and Technical Information of China (English)

    Zhaohui LIU; Wei QI; Weina WU; Yue LIU; Zhimin HE

    2008-01-01

    The effects of some sugars (glucose, mannose, fructose, sucrose and chitosan) and polyols (glycol, gly-cerol and sorbitol) as protective additive on the thermo-stability of β-mannanase were studied. The optimal reaction temperatures of β-mannanase and the ther-modynamics and the deactivation kinetics with or without additives were also investigated. The experimental results show that sucrose, chitosan and sorbitol could apparently improve the thermal stability of β-mannanase when their concentration was kept at 2 g/L. The optimal combina-tion additive proportion was sucrose: chitosan : sorbi-tol = 1 : 2 : 2 (molar ratio) using the orthogonal experimental design. The sucrose, chitosan, glycerol, sor-bitol and the combination additive might increase the optimal reaction temperature from 50℃ to about 60℃ due to their good protection effect. The thermal deactiva-tion curves of βmannanase accorded with the kinetic rules of first order reaction, and the corresponding kinetic and thermodynamic parameters were calculated. Meanwhile, the protective mechanism of the additives against deactivation of enzyme was also discussed.

  15. Additive Manufacturing Design Considerations for Liquid Engine Components

    Science.gov (United States)

    Whitten, Dave; Hissam, Andy; Baker, Kevin; Rice, Darron

    2014-01-01

    The Marshall Space Flight Center's Propulsion Systems Department has gained significant experience in the last year designing, building, and testing liquid engine components using additive manufacturing. The department has developed valve, duct, turbo-machinery, and combustion device components using this technology. Many valuable lessons were learned during this process. These lessons will be the focus of this presentation. We will present criteria for selecting part candidates for additive manufacturing. Some part characteristics are 'tailor made' for this process. Selecting the right parts for the process is the first step to maximizing productivity gains. We will also present specific lessons we learned about feature geometry that can and cannot be produced using additive manufacturing machines. Most liquid engine components were made using a two-step process. The base part was made using additive manufacturing and then traditional machining processes were used to produce the final part. The presentation will describe design accommodations needed to make the base part and lessons we learned about which features could be built directly and which require the final machine process. Tolerance capabilities, surface finish, and material thickness allowances will also be covered. Additive Manufacturing can produce internal passages that cannot be made using traditional approaches. It can also eliminate a significant amount of manpower by reducing part count and leveraging model-based design and analysis techniques. Information will be shared about performance enhancements and design efficiencies we experienced for certain categories of engine parts.

  16. The Effect Acid Addition on Characteristic Effervescent Tablet of Tamarillo

    Directory of Open Access Journals (Sweden)

    Fidela Violalita

    2015-01-01

    Full Text Available The aim of study was to determine the percentage of acid and its influence on characteristic effervescent tablet of tamarillo. The percentages of  acid addition that consist with citric acid and tartaric acid (1:1 were 15%, 20%, 25%, 30% and 35%. Water content, pH solution, vitamin C content, soluble duration, friability of tablet and organoleptic test on colour, aroma and flavour of tamarillo effervescent tablet were determined after addition of acid. The results showed that the difference in percentage of acid addition significantly affected to the water content, pH solution, soluble duration and friability of tablets. Based on organoleptic test, the tablet consist of 25% addition of acid was the best percentage of acid addition. The quality parameters in this percentage were the water content 6.09%, pH solution 4.80,  vitamin C 498.0800 mg/tablet, soluble duration 3.96 minute, friability of tablet 0.11%, while the averages of organoleptic test for colour were 3.40 (ordinary, aroma 3.36 (ordinary, and flavour 3.76 (like.

  17. Metal Additive Manufacturing: A Review of Mechanical Properties

    Science.gov (United States)

    Lewandowski, John J.; Seifi, Mohsen

    2016-07-01

    This article reviews published data on the mechanical properties of additively manufactured metallic materials. The additive manufacturing techniques utilized to generate samples covered in this review include powder bed fusion (e.g., EBM, SLM, DMLS) and directed energy deposition (e.g., LENS, EBF3). Although only a limited number of metallic alloy systems are currently available for additive manufacturing (e.g., Ti-6Al-4V, TiAl, stainless steel, Inconel 625/718, and Al-Si-10Mg), the bulk of the published mechanical properties information has been generated on Ti-6Al-4V. However, summary tables for published mechanical properties and/or key figures are included for each of the alloys listed above, grouped by the additive technique used to generate the data. Published values for mechanical properties obtained from hardness, tension/compression, fracture toughness, fatigue crack growth, and high cycle fatigue are included for as-built, heat-treated, and/or HIP conditions, when available. The effects of test orientation/build direction on properties, when available, are also provided, along with discussion of the potential source(s) (e.g., texture, microstructure changes, defects) of anisotropy in properties. Recommendations for additional work are also provided.

  18. SUNFLOWER HUSKS AS A SOURCE OF FUNCTIONAL FEED ADDITIVES

    Directory of Open Access Journals (Sweden)

    Khusid S. B.

    2015-03-01

    Full Text Available The article describes the results of the complex feed additive based on sunflower husk, enriched with beer wort with the addition of pumpkin pulp. We have studied the chemical composition of sunflower husk, which is the secondary resource of the processing plant raw material, selected methods of enrichment of this raw material with the help of fungi Trichoderma harzianum. Cellulolytic enzyme preparations on the basis of fungi of the genus Trichoderma for use in agriculture and animal feed production is often obtained when the surface method of cultivation. These drugs are cheap and contain a significant number of related hydrolytic enzymes, 29 such as amylase, protease, pectinase and hemicellulase, which are also important and valuable to the consumer. As a vitamin component of the feed additive we have selected a pumpkin pulp, which is a valuable feed for livestock and poultry is a source of carotene, fat and nitrogenous substances. We have also developed elements of technology for complex feed additive. We have created a comprehensive feed additive which can be used in the composition of diets in the feeding of farm animals and poultry

  19. Influence of boric acid additive size on green lubricant performance.

    Science.gov (United States)

    Lovell, Michael R; Kabir, M A; Menezes, Pradeep L; Higgs, C Fred

    2010-10-28

    As the industrial community moves towards green manufacturing processes, there is an increased demand for multi-functional, environmentally friendly lubricants with enhanced tribological performance. In the present investigation, green (environmentally benign) lubricant combinations were prepared by homogeneously mixing nano- (20 nm), sub-micrometre- (600 nm average size) and micrometre-scale (4 μm average size) boric acid powder additives with canola oil in a vortex generator. As a basis for comparison, lubricants of base canola oil and canola oil mixed with MoS(2) powder (ranging from 0.5 to 10 μm) were also prepared. Friction and wear experiments were carried out on the prepared lubricants using a pin-on-disc apparatus under ambient conditions. Based on the experiments, the nanoscale (20 nm) particle boric acid additive lubricants significantly outperformed all of the other lubricants with respect to frictional and wear performance. In fact, the nanoscale boric acid powder-based lubricants exhibited a wear rate more than an order of magnitude lower than the MoS(2) and larger sized boric acid additive-based lubricants. It was also discovered that the oil mixed with a combination of sub-micrometre- and micrometre-scale boric acid powder additives exhibited better friction and wear performance than the canola oil mixed with sub-micrometre- or micrometre-scale boric acid additives alone.

  20. The Additional Professional Training in the Late Russian Empire

    Directory of Open Access Journals (Sweden)

    Timur A. Magsumov

    2015-06-01

    Full Text Available The article reveals the experience of intensive organization and functioning of the system of additional professional training in the late imperial period of the Russian history, generated by the need of unfolded modernization in the country. The article is written on the basis of mass sources, including the regional archives of record keeping documentation and working in the mainstream of the study of basic organizational forms of additional training - agricultural courses, shopping classes and courses of technical drawing, also the author produces a macro shot of trends and directions, successes and challenges in its development. The additional professional training as a specific element of the education system of 20th century focusing on the real sector of economy has implemented the free practice-training based on the principles of interdisciplinarity, variability and the high role of self-education.